7.1.0.11

fix tests on ghc 8.10.7 (#1939 )
* fix tests on ghc 8.10.7 * fix test * fix schema dump test --------- Co-authored-by: Evgeny @ SimpleX Chat <[email protected]>
2026-10-12 11:39:56 +00:00 · 2026-10-11 22:33:06 +01:00 · 2026-10-11 20:36:51 +01:00 · 2026-10-11 11:52:24 +01:00 · 2026-10-11 07:37:33 +01:00 · 2026-10-10 23:15:19 +01:00
114 changed files with 4864 additions and 2937 deletions
@@ -66,8 +66,19 @@ jobs:
  build:
    name: "ubuntu-${{ matrix.os }}-${{ matrix.arch }}, GHC: ${{ matrix.ghc }}"
    needs: maybe-release
+    permissions:
+      contents: write
+      packages: write
    env:
      apps: "smp-server xftp-server ntf-server xftp"
+      opt: ${{ github.event_name == 'pull_request' && 'O0' || 'O2' }}
+      ghc_options: ${{ github.event_name == 'pull_request' && '--ghc-options=-O0' || '' }}
+      release: ${{ startsWith(github.ref, 'refs/tags/v') }}
+      postgres_dist: ${{ startsWith(github.ref, 'refs/tags/v') && 'dist-newstyle' || 'dist-postgres' }}
+      branch: ${{ github.base_ref || github.ref_name }}
+      cache_o0: ${{ github.event_name == 'push' && (github.ref == 'refs/heads/master' || github.ref == 'refs/heads/stable') }}
+      image_cache: ghcr.io/simplex-chat/simplexmq-build-cache:${{ matrix.os }}-${{ matrix.arch }}-ghc${{ matrix.ghc }}
+      source_hashes: dist-newstyle/sources.sha256
    runs-on: ${{ matrix.runner }}
    services:
      postgres:
@@ -146,6 +157,18 @@ jobs:
          sudo apt update
          sudo apt -y install postgresql-client-15

+      - name: Log in to GitHub Container Registry
+        if: matrix.should_run == true && env.release != 'true'
+        shell: bash
+        env:
+          GHCR_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        run: echo "$GHCR_TOKEN" | docker login ghcr.io -u "${{ github.actor }}" --password-stdin
+
+      - name: Compute image cache week
+        id: week
+        if: matrix.should_run == true && env.release != 'true'
+        run: echo "week=$(date -u +%G-W%V)" >> "$GITHUB_OUTPUT"
+
      - name: Build and cache Docker image
        if: matrix.should_run == true
        uses: simplex-chat/docker-build-push-action@v6
@@ -157,20 +180,14 @@ jobs:
          build-args: |
            TAG=${{ matrix.os }}
            GHC=${{ matrix.ghc }}
-
-      - name: Cache dependencies
-        if: matrix.should_run == true
-        uses: actions/cache@v4
-        with:
-          path: |
-            ~/.cabal/store
-            dist-newstyle
-          key: ubuntu-${{ matrix.os }}-${{ matrix.arch }}-ghc${{ matrix.ghc }}-${{ hashFiles('cabal.project', 'simplexmq.cabal') }}
+          cache-from: ${{ env.release != 'true' && format('type=registry,ref={0}-{1}', env.image_cache, steps.week.outputs.week) || '' }}
+          cache-to: ${{ github.event_name == 'push' && github.ref == 'refs/heads/master' && format('type=registry,ref={0}-{1},mode=max,ignore-error=true', env.image_cache, steps.week.outputs.week) || '' }}

      - name: Start container
        if: matrix.should_run == true
        shell: bash
        run: |
+          mkdir -p ~/.cabal
          docker run -t -d \
            --device /dev/fuse \
            --cap-add SYS_ADMIN \
@@ -181,21 +198,66 @@ jobs:
            -v ${{ github.workspace }}:/project \
            build/${{ matrix.os }}:latest

+      - name: Compute cache key prefixes
+        id: keys
+        if: matrix.should_run == true && env.release != 'true'
+        run: |
+          toolchain=$(docker exec builder dpkg-query -W -f '${db:Status-Status} ${binary:Package} ${Version}\n' 'binutils*' 'cpp*' 'gcc*' '*-dev' | grep '^installed ' | sha256sum | cut -c1-16)
+          target=${{ matrix.os }}-${{ matrix.arch }}-ghc${{ matrix.ghc }}-$toolchain
+          echo "deps=deps-$target" >> "$GITHUB_OUTPUT"
+          echo "dist=dist-$target" >> "$GITHUB_OUTPUT"
+
+      - name: Restore dependencies from cache
+        id: restore-deps
+        if: matrix.should_run == true && env.release != 'true'
+        uses: actions/cache/restore@v4
+        with:
+          path: ~/.cabal/store
+          key: ${{ steps.keys.outputs.deps }}-${{ env.branch }}-${{ github.sha }}
+          restore-keys: |
+            ${{ steps.keys.outputs.deps }}-${{ env.branch }}-
+            ${{ steps.keys.outputs.deps }}-
+
+      - name: Warn if dependencies not in cache
+        if: matrix.should_run == true && env.release != 'true' && steps.restore-deps.outputs.cache-matched-key == ''
+        run: echo "::warning title=Cache miss::${{ steps.keys.outputs.deps }}-${{ env.branch }}"
+
+      - name: Restore build directories from cache
+        id: restore-build
+        if: matrix.should_run == true && env.release != 'true'
+        uses: actions/cache/restore@v4
+        with:
+          path: |
+            dist-newstyle
+            dist-postgres
+          key: ${{ steps.keys.outputs.dist }}-${{ env.opt }}-${{ env.branch }}-${{ github.sha }}
+          restore-keys: |
+            ${{ steps.keys.outputs.dist }}-${{ env.opt }}-${{ env.branch }}-
+            ${{ steps.keys.outputs.dist }}-${{ env.opt }}-
+
+      - name: Warn if build directories not in cache
+        if: matrix.should_run == true && env.release != 'true' && steps.restore-build.outputs.cache-matched-key == ''
+        run: echo "::warning title=Cache miss::${{ steps.keys.outputs.dist }}-${{ env.opt }}-${{ env.branch }}"
+
+      - name: Set old timestamps on unchanged sources (GHC 8.10.7)
+        if: matrix.ghc == '8.10.7' && steps.restore-build.outputs.cache-matched-key != '' && hashFiles(env.source_hashes) != ''
+        run: scripts/ci/source-timestamps.sh restore ${{ env.source_hashes }}
+
      - name: Build smp-server, xftp-server (postgresql) and tests
        if: matrix.should_run == true
        shell: docker exec -t builder sh -eu {0}
        run: |
-          chmod -fR 777 ~/.cabal ./dist-newstyle || :; git config --global --add safe.directory '*'
-          cabal clean
+          chmod -fR 777 ~/.cabal ./dist-newstyle ./dist-postgres || :; git config --global --add safe.directory '*'
+          scripts/ci/prune-old-builds.sh dist-newstyle dist-postgres
          cabal update
-          cabal build --jobs=$(nproc) --enable-tests -fserver_postgres
+          cabal build --builddir=${{ env.postgres_dist }} --jobs=$(nproc) --enable-tests -fserver_postgres ${{ env.ghc_options }}
          mkdir -p /out
-          for i in smp-server xftp-server simplexmq-test; do
-            bin=$(find /project/dist-newstyle -name "$i" -type f -executable)
+          for i in smp-server xftp-server ntf-server simplexmq-test; do
+            bin=$(find /project/${{ env.postgres_dist }} -name "$i" -type f -executable)
            chmod +x "$bin"
-            mv "$bin" /out/
+            cp "$bin" /out/
          done
-          strip /out/smp-server /out/xftp-server
+          strip /out/smp-server /out/xftp-server /out/ntf-server

      - name: Copy simplexmq-test from container
        if: matrix.should_run == true
@@ -228,16 +290,17 @@ jobs:
          cat hashes.output >> "$GITHUB_OUTPUT"

      - name: Build everything else (standard)
+        id: build-standard
        if: matrix.should_run == true
        shell: docker exec -t builder sh -eu {0}
        run: |
-          cabal build --jobs=$(nproc)
+          cabal build --jobs=$(nproc) ${{ env.ghc_options }}
          mkdir -p /out
-          for i in ${{ env.apps }}; do
+          for i in smp-server xftp-server xftp; do
            bin=$(find /project/dist-newstyle -name "$i" -type f -executable)
            strip "$bin"
            chmod +x "$bin"
-            mv "$bin" /out/
+            cp "$bin" /out/
          done

      - name: Copy binaries from container and prepare them
@@ -282,6 +345,33 @@ jobs:
        env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

+      - name: Record source hashes (GHC 8.10.7)
+        if: matrix.should_run == true && matrix.ghc == '8.10.7'
+        shell: docker exec -t builder sh -eu {0}
+        run: scripts/ci/source-timestamps.sh record ${{ env.source_hashes }}
+
+      - name: Compute dependency cache key
+        id: hash-deps
+        if: matrix.should_run == true && env.release != 'true'
+        shell: bash
+        run: echo "hash=$(ls ~/.cabal/store/ghc-*/ | sha256sum | cut -c1-16)" >> "$GITHUB_OUTPUT"
+
+      - name: Save dependencies to cache
+        if: matrix.should_run == true && env.release != 'true' && steps.restore-deps.outputs.cache-matched-key != format('{0}-{1}-{2}', steps.keys.outputs.deps, env.branch, steps.hash-deps.outputs.hash)
+        uses: actions/cache/save@v4
+        with:
+          path: ~/.cabal/store
+          key: ${{ steps.keys.outputs.deps }}-${{ env.branch }}-${{ steps.hash-deps.outputs.hash }}
+
+      - name: Save build directories to cache
+        if: matrix.should_run == true && env.release != 'true' && steps.restore-build.outputs.cache-hit != 'true'
+        uses: actions/cache/save@v4
+        with:
+          path: |
+            dist-newstyle
+            dist-postgres
+          key: ${{ steps.keys.outputs.dist }}-${{ env.opt }}-${{ env.branch }}-${{ github.sha }}
+
      - name: Test
        if: matrix.should_run == true && matrix.arch == 'x86-64'
        timeout-minutes: 120
@@ -306,6 +396,52 @@ jobs:
            exit 1
          fi

+      - name: Remove -O2 build directories
+        id: remove-o2
+        if: env.cache_o0 == 'true' && !cancelled() && steps.build-standard.outcome == 'success'
+        shell: docker exec -t builder sh -eu {0}
+        run: rm -rf dist-newstyle dist-postgres
+
+      - name: Restore -O0 build directories from cache
+        id: restore-build-o0
+        if: ${{ !cancelled() && steps.remove-o2.outcome == 'success' }}
+        uses: actions/cache/restore@v4
+        with:
+          path: |
+            dist-newstyle
+            dist-postgres
+          key: ${{ steps.keys.outputs.dist }}-O0-${{ env.branch }}-${{ github.sha }}
+          restore-keys: |
+            ${{ steps.keys.outputs.dist }}-O0-${{ env.branch }}-
+            ${{ steps.keys.outputs.dist }}-O0-
+
+      - name: Set old timestamps on unchanged sources for -O0 build (GHC 8.10.7)
+        if: ${{ !cancelled() && matrix.ghc == '8.10.7' && steps.restore-build-o0.outputs.cache-matched-key != '' && hashFiles(env.source_hashes) != '' }}
+        run: scripts/ci/source-timestamps.sh restore ${{ env.source_hashes }}
+
+      - name: Build at -O0 for pull request caches
+        id: build-o0
+        if: ${{ !cancelled() && steps.remove-o2.outcome == 'success' }}
+        shell: docker exec -t builder sh -eu {0}
+        run: |
+          scripts/ci/prune-old-builds.sh dist-newstyle dist-postgres
+          cabal build --builddir=dist-postgres --jobs=$(nproc) --enable-tests -fserver_postgres --ghc-options=-O0
+          cabal build --jobs=$(nproc) --ghc-options=-O0
+
+      - name: Record source hashes for -O0 build (GHC 8.10.7)
+        if: ${{ !cancelled() && matrix.ghc == '8.10.7' && steps.build-o0.outcome == 'success' }}
+        shell: docker exec -t builder sh -eu {0}
+        run: scripts/ci/source-timestamps.sh record ${{ env.source_hashes }}
+
+      - name: Save -O0 build directories to cache
+        if: ${{ !cancelled() && steps.build-o0.outcome == 'success' && steps.restore-build-o0.outputs.cache-hit != 'true' }}
+        uses: actions/cache/save@v4
+        with:
+          path: |
+            dist-newstyle
+            dist-postgres
+          key: ${{ steps.keys.outputs.dist }}-O0-${{ env.branch }}-${{ github.sha }}
+
 # =============================
 #      Resolver test job
 # =============================
@@ -320,15 +456,14 @@ jobs:
      - name: Clone project
        uses: actions/checkout@v3

-      - name: Set up Python
-        # Matches the runtime stage of scripts/resolver/service/Dockerfile.
-        uses: actions/setup-python@v5
-        with:
-          python-version: "3.13"
+      - name: Set up uv
+        # uv takes Python from .python-version, the version of the Dockerfile's runtime stage.
+        uses: astral-sh/setup-uv@c18668ad3cf93ea998bef934396af7bb5c839dc7 # v10.2.0

-      - name: Install resolver dependencies
-        # Must match scripts/resolver/service/pyproject.toml.
-        run: python -m pip install "eth-hash[pycryptodome]>=0.7"
+      - name: Lint
+        working-directory: scripts/resolver/service
+        run: uv run --frozen ruff check .

      - name: Test
-        run: python -m unittest discover -s scripts/resolver/service -v
+        working-directory: scripts/resolver/service
+        run: uv run --frozen pytest -v
@@ -1,4 +1,8 @@
 *.lock
+# the resolver's Docker image and CI install exactly these
+!/scripts/resolver/service/uv.lock
+# local overrides of scripts/resolver/.env.example
+/scripts/resolver/.env
 *.db
 *.db.bak
 *.session.sql
@@ -31,7 +31,7 @@ source-repository-package
 source-repository-package
    type: git
    location: https://github.com/simplex-chat/direct-sqlcipher.git
-    tag: f814ee68b16a9447fbb467ccc8f29bdd3546bfd9
+    tag: 2330df3dc8c4b660674d3c02d76bb86f66c2abee

 source-repository-package
    type: git
@@ -719,23 +719,32 @@ Small_random (small * out, void *random_ctx, sntrup761_random_func * random)

 /* ----- Streamlined NTRU Prime Core */

+/* x^p-x-1 has a degree-19 factor mod 3, so a random g is not invertible in R3
+   with probability about 3^-19; KeyGen_attempts failures in a row mean a broken RNG */
+#define KeyGen_attempts 10
+
 /* h,(f,ginv) = KeyGen() */
-static void
+/* returns 0 if KeyGen succeeded; else -1 */
+static int
 KeyGen (Fq * h, small * f, small * ginv, void *random_ctx,
        sntrup761_random_func * random)
 {
  small g[p];
  Fq finv[p];
+  int i;

-  for (;;)
+  for (i = 0; i < KeyGen_attempts; ++i)
    {
      Small_random (g, random_ctx, random);
      if (R3_recip (ginv, g) == 0)
        break;
    }
+  if (i == KeyGen_attempts)
+    return -1;
  Short_random (f, random_ctx, random);
  Rq_recip3 (finv, f);          /* always works */
  Rq_mult_small (h, finv, g);
+  return 0;
 }

 /* c = Encrypt(r,h) */
@@ -884,18 +893,21 @@ typedef small Inputs[p];        /* passed by reference */
 #define PublicKeys_bytes Rq_bytes

 /* pk,sk = ZKeyGen() */
-static void
+/* returns 0 if KeyGen succeeded; else -1 */
+static int
 ZKeyGen (unsigned char *pk, unsigned char *sk, void *random_ctx,
         sntrup761_random_func * random)
 {
  Fq h[p];
  small f[p], v[p];

-  KeyGen (h, f, v, random_ctx, random);
+  if (KeyGen (h, f, v, random_ctx, random) != 0)
+    return -1;
  Rq_encode (pk, h);
  Small_encode (sk, f);
  sk += Small_bytes;
  Small_encode (sk, v);
+  return 0;
 }

 /* C = ZEncrypt(r,pk) */
@@ -960,19 +972,21 @@ HashSession (unsigned char *k, int b, const unsigned char *y,
 /* ----- Streamlined NTRU Prime */

 /* pk,sk = KEM_KeyGen() */
-void
+int
 sntrup761_keypair (unsigned char *pk, unsigned char *sk, void *random_ctx,
                   sntrup761_random_func * random)
 {
  int i;

-  ZKeyGen (pk, sk, random_ctx, random);
+  if (ZKeyGen (pk, sk, random_ctx, random) != 0)
+    return -1;
  sk += SecretKeys_bytes;
  for (i = 0; i < PublicKeys_bytes; ++i)
    *sk++ = pk[i];
  random (random_ctx, Inputs_bytes, sk);
  sk += Inputs_bytes;
  Hash_prefix (sk, 4, pk, PublicKeys_bytes);
+  return 0;
 }

 /* c,r_enc = Hide(r,pk,cache); cache is Hash4(pk) */
@@ -19,7 +19,8 @@

 typedef void sntrup761_random_func (void *ctx, size_t length, uint8_t *dst);

-void
+/* returns 0 on success, -1 if the RNG never produced an invertible polynomial */
+int
 sntrup761_keypair (uint8_t *pk, uint8_t *sk,
                   void *random_ctx, sntrup761_random_func *random);

@@ -7,6 +7,7 @@ This file provides guidance on coding style and approaches and on building the c
 When designing code and planning implementations:
 - Apply adversarial thinking, and consider what may happen if one of the communicating parties is malicious.
 - Formulate an explicit threat model for each change - who can do which undesirable things and under which circumstances.
+- Use the default cryptographic primitive for each purpose from the [primitive registry](../protocol/crypto-registry.md); any exception requires review, and the registry must be updated with every new primitive use or domain-separation string.

 ## Code Quality Standards

@@ -1,309 +0,0 @@
-# Implementation plan: client address statistics
-
-Scope:
-
- SMP server
- XFTP server
- NTF server
-
-## Rules
-
- Counters per address are kept in memory only.
- Counters are neither saved nor restored.
- Prometheus receives aggregates across addresses only.
- Addresses are not logged.
- Addresses are shown only by a control port command.
-
-## Address key
-
-```
-data AddrKey
-  = AKIPv4 Word32
-  | AKIPv6 Word64
-```
-
-Key of a socket address:
-
- IPv4 address: `AKIPv4`.
- IPv6 address in `::ffff:0:0/96`: `AKIPv4` of its last 32 bits.
- Other IPv6 address: `AKIPv6` of its first 64 bits.
- Other address types: not counted.
-
-Text of a key:
-
- `AKIPv4`: `a.b.c.d`.
- `AKIPv6`: `xxxx:xxxx:xxxx:xxxx::/64`.
-
-## Counters
-
-Each server has a fixed set of counters:
-
-```
-class (Ord c, Enum c, Bounded c) => AddrCounter c where
-  counterName :: c -> Text
-  counterBounds :: c -> [Int]
-  connectionsCounter :: c
-```
-
-`counterName` is the Prometheus label value and the control port argument.
-
-Counters of every server:
-
- `connections`: connections passed to the protocol handler, after TLS setup.
- One counter per command tag, named by the tag: an attempt is counted, failed ones included.
- `errors`: parse failures and authorization failures.
-
-Command tag types:
-
- SMP: `CommandTag` in `Simplex.Messaging.Protocol`.
- XFTP: `FileCommandTag` in `Simplex.FileTransfer.Protocol`.
- NTF: `NtfCommandTag` in `Simplex.Messaging.Notifications.Protocol`.
-
-A function from a command to its counter is added for each server.
-
-SMP proxy counters, by result of `PRXY`:
-
- `PRXY_own`: own server.
- `PRXY_connected`: other server with an existing connection.
- `PRXY_new`: other server with a new connection.
- `PRXY_onion`: server with onion hosts only.
- `PRXY_failed`: error.
-
-SMP proxy counters, by result of `PFWD`:
-
- `PFWD_own`: own server.
- `PFWD_other`: other server.
- `PFWD_onion`: server with onion hosts only.
- `PFWD_failed`: error other than a protocol error, or no session.
-
-Class precedence: `failed`, then `own`, then `onion`.
-
-XFTP counters:
-
- `upload_kb`: kilobytes of chunks stored by successful `FPUT`.
- `download_kb`: kilobytes of chunks sent for `FGET`.
- `recipients`: recipient keys added by successful `FNEW` and `FADD`.
-
-## Periods
-
- A period is a fixed interval of `period` seconds. The first period starts at server start.
- Counts of the current period are accumulated as events occur.
- Counts of the previous period are the counts of the last closed period.
- Histograms use the counts of closed periods.
- The control port command shows the previous and the current counts, sorted by their sum.
-
-## Module `Simplex.Messaging.Server.AddressStats`
-
-```
-data AddrStats c = AddrStats
-  { connectionsCount :: TVar Int,
-    current :: Map c (IORef Int),
-    previous :: Map c (IORef Int)
-  }
-
-type AddrStatsMap c = TMap AddrKey (AddrStats c)
-
-data AddrHistogram = AddrHistogram
-  { bucketCounts :: [Int],
-    countSum :: Int,
-    addressCount :: Int,
-    periodMax :: Int
-  }
-
-newtype AddressStatsConfig = AddressStatsConfig
-  { period :: Int64
-  }
-```
-
- `current` and `previous` contain one cell per counter, created when the address is inserted.
- `bucketCounts` are cumulative counts per bound, from server start.
-
-Bounds:
-
- `countBounds`: 1 to 9, then R10 values times powers of 10, rounded half up to integers, up to 1,000,000: 60 bounds.
- `kilobyteBounds`: the same, up to 100,000,000: 80 bounds.
- R10 values: 1, 1.25, 1.6, 2, 2.5, 3.15, 4, 5, 6.3, 8.
-
-Functions:
-
- `addrKey :: SockAddr -> Maybe AddrKey`
- `addrKeyText :: AddrKey -> Text`
- `counterByName :: AddrCounter c => Text -> Maybe c`
- `withAddrStats :: AddrCounter c => Maybe (AddrStatsMap c) -> Socket -> (Maybe (AddrStats c) -> IO a) -> IO a`:
-  1. The peer address is read with `getPeerName`. On an exception, the connection is not counted.
-  2. In one transaction, the entry is looked up or inserted, and `connectionsCount` is incremented.
-  3. `connectionsCounter` is incremented.
-  4. The action is run. `connectionsCount` is decremented in `finally`.
- `incAddrCounter :: AddrCounter c => AddrStats c -> c -> IO ()`
- `addAddrCounter :: AddrCounter c => AddrStats c -> c -> Int -> IO ()`
- `rolloverAddrStats :: AddrCounter c => AddrStatsMap c -> IORef (Map c AddrHistogram) -> IO ()`, in one pass over the entries, per counter:
-  1. The `current` cell is set to 0. Its value is the closing count.
-  2. A non-zero closing count is added to the histogram: to each bucket with a bound at or above it, to `countSum`, and to `addressCount`.
-  3. `periodMax` is the largest closing count.
-  4. The `previous` cell is set to the closing count.
-  
-  After the pass, an entry is deleted when `connectionsCount` is 0 and every closing count is 0. `connectionsCount` is read in the deleting transaction.
- `addressStatsThread :: AddrCounter c => AddressStatsConfig -> AddrStatsMap c -> IORef (Map c AddrHistogram) -> IO ()`: `rolloverAddrStats` every `period` seconds.
- `topAddresses :: AddrCounter c => AddrStatsMap c -> c -> Int -> IO [(AddrKey, Int, Int)]`: the key, previous count and current count of the counter, for up to the given number of entries, sorted by the sum of both counts, largest first. Entries with both counts 0 are excluded.
- `addrHistogramMetrics :: AddrCounter c => Text -> Map c AddrHistogram -> Text`: Prometheus text for a metric name prefix.
-
-## Prometheus
-
-Written with the other metrics of each server, when both `addressStats` and `prometheus_interval` are set:
-
-```
-# TYPE <prefix>_client_address_period_count histogram
-<prefix>_client_address_period_count_bucket{counter="<name>",le="<bound>"} <addresses>
-<prefix>_client_address_period_count_bucket{counter="<name>",le="+Inf"} <addresses>
-<prefix>_client_address_period_count_sum{counter="<name>"} <sum>
-<prefix>_client_address_period_count_count{counter="<name>"} <addresses>
-# TYPE <prefix>_client_address_period_max gauge
-<prefix>_client_address_period_max{counter="<name>"} <max>
-```
-
-Prefixes:
-
- `simplex_smp`
- `simplex_xftp`
- `simplex_ntf`
-
-In scrape jobs, `convert_classic_histograms_to_nhcb: true` is set.
-
-## Configuration
-
-The same INI section in `smp-server.ini`, `file-server.ini` and `ntf-server.ini`:
-
-```
-[ADDRESS_STATS]
-enable = off
-period = 300
-```
-
- `enable = off` or an absent section: statistics are off.
- `period`: seconds.
-
-`iniAddressStats :: Ini -> Maybe AddressStatsConfig` is added to `Simplex.Messaging.Server.CLI`.
-
-Added to `ServerConfig`, `XFTPServerConfig` and `NtfServerConfig`:
-
-```
-addressStats :: Maybe AddressStatsConfig
-```
-
-The section is written by the `init` command of each server with `enable = off`.
-
-With `addressStats` set:
-
- an `AddrStatsMap` and a histogram reference are added to the server env
- `addressStatsThread` is added to the server threads
-
-## Control port
-
-Command of the SMP, XFTP and NTF control ports:
-
-```
-addresses <counter> [<n>]
-```
-
- User role.
- `<counter>`: a counter name.
- `<n>`: number of addresses, 10 when absent.
-
-Output of `topAddresses`:
-
-```
-address,previous,current
-<key>,<count>,<count>
-```
-
-Errors:
-
- Unknown counter name: `error: unknown counter`.
- Statistics off: `error: address statistics are off`.
-
-Changes:
-
- `CPAddresses Text (Maybe Int)` is added to `ControlProtocol` in `Simplex.Messaging.Server.Control`, `Simplex.FileTransfer.Server.Control` and `Simplex.Messaging.Notifications.Server.Control`.
- `addresses` is added to the `help` output of each control port.
-
-## SMP server
-
-In `Simplex.Messaging.Server`:
-
- `runServer`: in the branch without HTTP, `runTransportServerState_` is called with `TLSServerCredential {credential = smpCreds, sniCredential = Nothing}`. In both branches, the socket is passed to `runClient`.
- `runClient` is run in `withAddrStats`. The `AddrStats` is passed to `runClientTransport`.
- `clientAddrStats :: Maybe (AddrStats SMPAddrCounter)` is added to `Client`, as a parameter of `newClient`.
- `receive`:
-  - The counter of each parsed transmission is incremented.
-  - `errors` is incremented for each parse error and each failed verification.
- `processProxiedCmd`: the proxy counter is incremented when the result of `PRXY` or `PFWD` is known.
-
-## NTF server
-
-In `Simplex.Messaging.Notifications.Server`:
-
- `runServer`: `runTransportServerState_` is called with a new `SocketState` and `TLSServerCredential {credential = srvCreds, sniCredential = Nothing}`. The socket is passed to `runClient`.
- `runClient` is run in `withAddrStats`. The `AddrStats` is passed to `runNtfClientTransport`.
- `ntfClientAddrStats :: Maybe (AddrStats NtfAddrCounter)` is added to `NtfServerClient`, as a parameter of `newNtfServerClient`.
- `receive`: counting as in the SMP server.
-
-## XFTP server
-
-In `Simplex.Messaging.Transport.HTTP2.Server`:
-
- A parameter `Socket -> SessionId -> IO () -> IO ()` is added to `runHTTP2Server`. The handler of each connection is run inside it, after TLS setup.
- In `getHTTP2Server`, the wrapper only runs the handler.
-
-In `Simplex.FileTransfer.Server`:
-
- `TMap SessionId (AddrStats XFTPAddrCounter)` is created in `runServer`.
- In the connection wrapper, the handler is run in `withAddrStats`. The `AddrStats` is inserted in the map before the handler, and deleted in `finally`.
- `addrStats :: Maybe (AddrStats XFTPAddrCounter)` is added to `XFTPTransportRequest`. It is looked up by session ID for each request.
- `processRequest`:
-  - The counter of each decoded command is incremented.
-  - `errors` is incremented for each decoding error and each failed verification.
- `upload_kb` is increased by the chunk size, rounded up to kilobytes, after a successful `FPUT`.
- `download_kb` is increased by the chunk size, rounded up to kilobytes, when an `FGET` response with the file is sent.
- `recipients` is increased by the number of recipient keys after a successful `FNEW` or `FADD`.
-
-## Tests
-
-`CoreTests.AddressStatsTests`:
-
- `addrKey`:
-  - IPv4 address
-  - IPv4-mapped IPv6 address
-  - two IPv6 addresses in one /64: one key
-  - two IPv6 addresses in different /64: two keys
- bounds:
-  - `countBounds` values
-  - `kilobyteBounds` values
- `counterByName` of each counter name
- `rolloverAddrStats`:
-  - histogram buckets, sum, address count, and max
-  - zero counts not added to histograms
-  - previous counts set to closing counts
-  - entry with an open connection kept
-  - entry with closing counts kept
-  - entry without connections and closing counts deleted
- `topAddresses`:
-  - order by the sum of previous and current counts
-  - number of entries limited
-  - entries with both counts 0 excluded
- `addrHistogramMetrics` output
- command to counter function of each server
-
-Server tests, with `addressStats` set and `period` 1:
-
- SMP basic queue tests
- SMP proxy tests
- XFTP basic file tests
- NTF basic token tests
-
-Control port test, SMP server with `addressStats` and a control port set:
-
- after messages are sent, `addresses SEND` lists the test client address
- `addresses` without authentication returns `AUTH`
- `addresses` with an unknown counter returns `error: unknown counter`
-
-`CLITests`: `enable = off` is checked in `[ADDRESS_STATS]` of each generated INI.
@@ -0,0 +1,62 @@
+# Fast rotation: draining the old receive queue
+
+Recipient only. The sender is unchanged.
+
+## Decisions
+
+- New `RcvSwitchStatus` value:
+
+  | constructor      | encoding        |
+  |------------------|-----------------|
+  | `RSReceivedQEND` | `received_qend` |
+
+  - Stored in `rcv_queues.switch_status`.
+  - `canAbortRcvSwitch` returns `False` for it.
+- `qEndMsg`, by the queue that delivered `QEND`:
+  - the queue named in `QEND`: the named queue is marked deleted, `ICDeleteRcvQueue` is enqueued.
+  - the new queue: the named queue is set to `RSReceivedQEND` and stays subscribed.
+  - `NSCCreate` and `SWITCH QDRcv SPCompleted`: sent when the named queue had no `RSReceivedQEND`.
+- Deletion of an `RSReceivedQEND` queue:
+  - trigger: `OK` response to an `ACK` on that queue, without a `GET` lock on it.
+  - action: the queue is marked deleted, `ICDeleteRcvQueue` is enqueued.
+- Bound, a `cleanupManager` step, for each connection with an `RSReceivedQEND` queue:
+  - condition: another receive queue of the connection has an active subscription.
+  - `delete_errors + 1 < deleteErrorCount`: `delete_errors` is incremented.
+  - otherwise: the queue is deleted as above; the first `DEL` error of `ICDeleteRcvQueue` removes it locally.
+- `ackSMPMessage` result, `type QueueDrained = Bool`:
+  - `OK`: `True`.
+  - `MSG`: `False`; the message is written to `msgQ`.
+- Apps: `received_qend` is added to `RcvSwitchStatus`.
+- Migration `20261008_rcv_switch_status`, SQLite and Postgres:
+  - up: index `idx_rcv_queues_switch_status` on `rcv_queues(switch_status)`.
+  - down: `received_qend` is set to `NULL`, the index is dropped.
+
+## Mechanics
+
+- `Agent/Protocol.hs`: `RSReceivedQEND`.
+- `Agent/Store.hs`: `canAbortRcvSwitch`.
+- `Client.hs`: `QueueDrained`; `ackSMPMessage` returns it.
+- `Agent/Client.hs`: `sendAck` returns `QueueDrained`.
+- `Agent/Store/AgentStore.hs`: `getEndedRcvQueueConnIds`:
+
+  ```sql
+  SELECT conn_id FROM rcv_queues WHERE switch_status = ? AND deleted = 0
+  ```
+
+- `Agent.hs`:
+  - `deleteRcvQueueAsync`: `setRcvQueueDeleted`, then `ICDeleteRcvQueue`.
+  - `qEndMsg`.
+  - `ackQueueMessage`.
+  - `cleanupManager`: `expireEndedRcvQueues`.
+- Apps:
+  - `apps/ios/SimpleXChat/APITypes.swift`
+  - `apps/multiplatform/common/src/commonMain/kotlin/chat/simplex/common/model/SimpleXAPI.kt`
+
+## Tests
+
+- `QEND` on the new queue while a message waits on the old queue:
+  - the message is delivered;
+  - the old queue is deleted after the `ACK` that returns `OK`.
+- The same with a recipient restart before the `ACK`.
+- Old server stopped: the old queue is deleted by the bound.
+- Downgrade: `received_qend` is cleared, other switch statuses are kept.
@@ -0,0 +1,52 @@
+# Delayed AUTH error responses
+
+## Decisions
+
+- Responses that include `ERR AUTH` are sent at the next multiple of the delay after the start time.
+- Delayed response sets:
+
+  | Source | Responses sent together | Start time |
+  |---|---|---|
+  | `receive`, failed verification | verification and parsing errors of one received block | block receipt |
+  | `client`, command processing | responses and messages of one batch | batch read from `rcvQ` |
+  | `RFWD`, forwarded command | the `RRES` of that command | start of forwarded command processing |
+
+- A thread created by `forkClient` writes the responses to the send queue.
+- Delay 0: the responses are written to the send queue directly.
+- `authDelayExceeded`: incremented when processing took longer than the delay.
+  - Prometheus counter `simplex_smp_auth_delay_exceeded`.
+  - Not saved in the stats backup.
+  - Not in the daily stats log.
+- Configuration:
+
+  | Item | Value |
+  |---|---|
+  | INI section | `TRANSPORT` |
+  | INI key | `auth_error_delay_ms` |
+  | default | 50 |
+  | `ServerConfig` field | `authErrorDelay`, microseconds |
+  | test servers | 20 ms |
+
+- AUTH timing test: elapsed time of 5 requests, test servers' delay.
+- Out of scope: NTF and XFTP servers.
+
+## Mechanics
+
+- `Server.hs`:
+  - `isAuthError`: response is `ERR AUTH`.
+  - `sendResponses`: responses with `ERR AUTH` to `sendAfterDelay`, others to the send queue.
+  - `sendAfterDelay`: writes responses to the send queue at the next multiple of the delay.
+  - `receive`: block receipt time from the `rcvActiveAt` reading.
+  - `client`: batch time.
+  - `processForwardedCommand`: start time.
+- `Server/Env/STM.hs`: `authErrorDelay` field, `defaultAuthErrorDelayMs`.
+- `Server/Stats.hs`: `authDelayExceeded` in `ServerStats` and `ServerStatsData`.
+- `Server/Prometheus.hs`: `simplex_smp_auth_delay_exceeded`.
+- `Server/Main.hs`: INI value.
+- `Server/Main/Init.hs`: INI template line.
+- `simplexmq.cabal`: `timeit` removed from the test suite.
+- `tests/SMPClient.hs`: `authErrorDelay = 20000`.
+- `tests/ServerTests.hs`:
+  - delayed AUTH for wrong key, absent queue, absent link and suspended queue; immediate `SOK`.
+  - AUTH timing test measures elapsed time.
+- `tests/SMPProxyTests.hs`: delayed AUTH to forwarded `SEND` and `LGET`.
@@ -85,7 +85,7 @@ SMP agent protocol has 2 main parts:

 ![Duplex connection procedure](./diagrams/duplex-messaging/duplex-creating.svg)

-The procedure of establishing a duplex connection is explained on the example of Alice and Bob creating a bi-directional connection consisting of two unidirectional (simplex) queues, using SMP agents (A and B) to facilitate it, and two different SMP routers (which could be the same router). It is shown on the diagram above and has these steps:
+The procedure of establishing a duplex connection is explained on the example of Alice (the initiating party) and Bob (the joining party) creating a bi-directional connection consisting of two unidirectional (simplex) queues, using SMP agents (A and B) to facilitate it, and two different SMP routers (which could be the same router). It is shown on the diagram above and has these steps:

 1. Alice requests the new connection from the SMP agent A using agent `createConnection` api function.
 2. Agent A creates an SMP queue on the router (using [SMP protocol](./simplex-messaging.md) `NEW` command) and responds to Alice with the invitation that contains queue information and the encryption keys Bob's agent B should use. The invitation format is described in [Connection link](connection-link-1-time-invitation-and-contact-address).
@@ -208,7 +208,7 @@ This syntax of decrypted SMP client message body is defined by `decryptedAgentMe
 Decrypted SMP message client body can be one of 4 types:
 - `agentConnInfo` - used by the initiating party when confirming reply queue - sent in `agentConfirmation` envelope.
 - `agentConnInfoReply` - used by accepting party, includes reply queue(s) in the initial confirmation - sent in `agentConfirmation` envelope.
- `agentRatchetInfo` - used to pass additional information when renegotiating double ratchet encryption - sent in `agentRatchetKey` envelope.
+- `agentRatchetInfo` - used to pass additional information when renegotiating double ratchet encryption - sent in `agentRatchetKey` envelope. A key sent in reply to another key includes the hash of that key; agents do not reply to such keys.
 - `agentMessage` - all other agent messages.

 `agentMessage` contains these parts:
@@ -233,7 +233,8 @@ connInfo = *OCTET
 agentConnInfoReply = %s"D" smpQueues connInfo
 smpQueues = length 1*newQueueInfo ; NonEmpty list of reply queues
 agentRatchetInfo = %s"R" ratchetInfo
-ratchetInfo = *OCTET
+ratchetInfo = [answeredKeyHash *OCTET] ; bytes after answeredKeyHash are ignored
+answeredKeyHash = %s"0" / (%s"1" shortString) ; "0" in a key that starts renegotiation, otherwise SHA-256 of the two raw public keys of the answered key

 agentMessage = %s"M" agentMsgHeader aMessage
 agentMsgHeader = agentMsgId prevMsgHash
@@ -0,0 +1,189 @@
+Revision 1, 2026-10-01
+
+# SimpleX Network: cryptographic primitive registry
+
+The cryptographic primitives, constructions and domain-separation strings used by this repository, and which of them new code may use. For the threat model see [Security](./security.md).
+
+Module aliases follow the codebase: `C` = [Simplex.Messaging.Crypto](../src/Simplex/Messaging/Crypto.hs), `LC` = [Crypto.Lazy](../src/Simplex/Messaging/Crypto/Lazy.hs), `CR` = [Crypto.Ratchet](../src/Simplex/Messaging/Crypto/Ratchet.hs), `SL` = [Crypto.ShortLink](../src/Simplex/Messaging/Crypto/ShortLink.hs), `KEM` = [Crypto.SNTRUP761](../src/Simplex/Messaging/Crypto/SNTRUP761.hs) and [its bindings](../src/Simplex/Messaging/Crypto/SNTRUP761/Bindings.hs), `BBS` = [Crypto.BBS](../src/Simplex/Messaging/Crypto/BBS.hs). Lengths are in bytes.
+
+## Table of contents
+
+- [Policy](#policy)
+- [Defaults for new code](#defaults-for-new-code)
+- [Primitives](#primitives)
+- [SimpleX box constructions](#simplex-box-constructions)
+- [Domain separation and KDF inputs](#domain-separation-and-kdf-inputs)
+- [Nonces and IVs](#nonces-and-ivs)
+- [Implementation sources](#implementation-sources)
+- [xftp-web (TypeScript)](#xftp-web-typescript)
+- [Tests](#tests)
+
+## Policy
+
+- New code uses the default primitive for its purpose from [Defaults for new code](#defaults-for-new-code).
+- Using any other primitive, or a primitive marked *restricted* outside its listed purpose, requires a written justification in the pull request and review by a maintainer responsible for cryptography.
+- *Legacy-only* primitives stay only for the existing wire formats and stored data listed below. Do not add call sites.
+- Every new HKDF info string or hash prefix must be unique, start with `SimpleX`, and be added to [Domain separation and KDF inputs](#domain-separation-and-kdf-inputs).
+- Changing a primitive, key length, KDF input, info string or nonce construction changes the wire format. It requires a protocol version and an update of this registry and of the affected `protocol/` specification.
+
+Status values used below:
+
+| Status | Meaning |
+|---|---|
+| Default | Approved and preferred for new code for this purpose |
+| Approved | Approved for new code for this purpose when the default does not fit |
+| Restricted | Approved only for the listed purpose (external interoperability or a single protocol) |
+| Legacy-only | Kept for existing wire formats or stored data; no new call sites |
+
+## Defaults for new code
+
+| Purpose | Default | Functions |
+|---|---|---|
+| Signature | Ed25519 | `C.sign'`, `C.verify'` with `C.SEd25519` |
+| Key agreement | X25519 | `C.generateKeyPair`, `C.dh'` |
+| Post-quantum KEM | sntrup761 | `KEM.sntrup761Keypair`, `sntrup761Enc`, `sntrup761Dec` |
+| Hybrid DH + KEM secret | HKDF-SHA512 over `dh \|\| kemSecret` with a new info string, as in `CR.rootKdf` | `C.hkdf` |
+| Authenticated encryption | XSalsa20-Poly1305 [SimpleX secretbox](#simplex-box-constructions) | `C.sbEncrypt`/`C.sbDecrypt`, `LC.sbEncryptTailTag` for streams |
+| Authenticated encryption with a DH secret | XSalsa20-Poly1305 [SimpleX crypto_box](#simplex-box-constructions) | `C.cbEncrypt`/`C.cbDecrypt` |
+| Forward-secret symmetric session | HKDF-SHA512 key chain | `C.sbcInit`, `C.sbcHkdf` |
+| KDF | HKDF-SHA512 | `C.hkdf` |
+| Hash commitment, derived identifier | SHA3-256 | `C.sha3_256` |
+| Certificate fingerprint | SHA-256 X.509 fingerprint | `C.signedFingerprint`, `C.certificateFingerprint` |
+| Randomness | ChaChaDRG seeded from system entropy | `C.newRandom`, `C.randomBytes` and the `random*` helpers |
+
+## Primitives
+
+| Primitive | Status | Purpose and protocol | Implementation | Lengths |
+|---|---|---|---|---|
+| Ed25519 | Default | SMP/NTF/XFTP queue and file keys (agent default `rcvAuthAlg`, `sndAuthAlg` in [Agent/Env/SQLite.hs](../src/Simplex/Messaging/Agent/Env/SQLite.hs)), short-link signatures and owner auth (`SL.encodeSign`, `SL.newOwnerAuth`), XRCP identity and session keys ([RemoteControl/Invitation.hs](../src/Simplex/RemoteControl/Invitation.hs)), agent service request signatures, client/service TLS certificates ([Transport/Credentials.hs](../src/Simplex/Messaging/Transport/Credentials.hs)) | crypton `Crypto.PubKey.Ed25519` via `C.sign'`/`C.verify'` | pub 32, priv 32, sig 64; X.509 SPKI 44 |
+| Ed448 | Approved | Server CA and online certificates (default `signAlgorithm = ED448` in [Server/CLI.hs](../src/Simplex/Messaging/Server/CLI.hs)); accepted for SMP command signatures and TLS | crypton `Crypto.PubKey.Ed448`; server key generation by the `openssl genpkey` CLI | pub 57, priv 57, sig 114; SPKI 69 |
+| X25519 | Default | Per-queue e2e and server-to-recipient `crypto_box` keys, SMP session DH, command authenticator (SMP v7+), proxy (PRXY/PFWD), notification tokens, XFTP chunk transport, XRCP hello and announcements | crypton `Crypto.PubKey.Curve25519` via `C.dh'` | pub 32, priv 32, secret 32; SPKI 44 |
+| X448 | Restricted | E2E double ratchet only: X3DH and DH ratchet (`CR.RatchetX448`, E2E v3) | crypton `Crypto.PubKey.Curve448` | pub 56, priv 56, secret 56 |
+| sntrup761 | Default | PQ KEM in double ratchet (E2E v3, agent v5+) and XRCP v1 hello | Vendored C [cbits/sntrup761.c](../cbits/sntrup761.c) via FFI; randomness from ChaChaDRG through `haskell_rng_func` ([Bindings/RNG.hs](../src/Simplex/Messaging/Crypto/SNTRUP761/Bindings/RNG.hs)) | pk 1158, sk 1763, ct 1039, shared 32 |
+| XSalsa20-Poly1305, SimpleX crypto_box | Default | SMP message bodies (server to recipient), per-queue e2e envelope, confirmations, proxy forwarding, notifications, XRCP hello, XFTP chunk transport | crypton `Crypto.Cipher.XSalsa`, `Crypto.MAC.Poly1305`; `C.cryptoBox`, `LC.cbInit` | key 32 (DH secret), nonce 24, tag 16 |
+| XSalsa20-Poly1305, SimpleX secretbox | Default | SMP transport block encryption (SMP v11+), short-link data (SMP v15+), XFTP file encryption, local file encryption ([Crypto/File.hs](../src/Simplex/Messaging/Crypto/File.hs)), XRCP session | same; `C.sbEncrypt`, `LC.sbEncryptTailTag`, `LC.sbInit` | key 32, nonce 24, tag 16 |
+| crypto_box authenticator | Approved | Deniable sender command authorization with X25519 queue keys (SMP v7+); agent currently creates Ed25519 keys | `C.cbAuthenticate`, `C.cbVerify`: `crypto_box(sha512(msg))` | 80 = 64 + 16 |
+| AES-256-GCM, 16-byte IV | Legacy-only | Double ratchet header and body (E2E v3, [pqdr.md](./pqdr.md)) | crypton `Crypto.Cipher.AES`, `Crypto.Cipher.Types`; `C.encryptAEAD`, `C.decryptAEAD`, `C.initAEAD`; J0 = GHASH(IV) as NIST SP 800-38D defines for non-96-bit IVs | key 32, IV 16, tag 16; padded header 88 (PQ off) or 2310 (PQ on), `CR.paddedHeaderLen` |
+| AES-256-GCM, 12-byte IV | Restricted | WebRTC frame encryption in simplex-chat (`Simplex.Chat.Mobile.WebRTC`), for WebCrypto interoperability | `C.encryptAESNoPad`, `C.decryptAESNoPad`, `C.initAEADGCM`, `C.GCMIV` | key 32, IV 12, tag 16 |
+| HKDF-SHA512 | Default | All KDFs listed in [Domain separation](#domain-separation-and-kdf-inputs) | crypton `Crypto.KDF.HKDF` with `SHA512`; `C.hkdf` (extract + expand) | output per use, at most 255 * 64 |
+| SHA-256 | Default for X.509 fingerprints, otherwise Restricted | X.509 fingerprints (`C.KeyHash`, server identity, XRCP CA, service certificate hash, SMP v16+), XFTP chunk digests, agent message hashes, `requestCode`, ratchet key dedup hash, security code `codeAD = sha256(rcAD)` | crypton; `C.sha256Hash`, `LC.sha256Hash`, `getFingerprint ... HashSHA256` | 32 |
+| SHA-512 | Restricted | XFTP file digests and file description hash, input of the crypto_box authenticator | crypton; `C.sha512Hash`, `LC.sha512Hash` | 64 |
+| SHA-512 (inside sntrup761) | Restricted | sntrup761 internal hash | [cbits/sha512.c](../cbits/sha512.c) calls OpenSSL `SHA512()` from the system `libcrypto` (`extra-libraries: crypto`) | 64 |
+| SHA3-256 | Default | Short-link key `sha3_256(fixedData)` (SMP v15+), XRCP hybrid secret, service request binding (agent v8) | crypton; `C.sha3_256`, `KEM.kemHybridSecret` | 32 |
+| SHA3-384 | Restricted | Client-supplied sender ID: first 24 bytes of `sha3_384(corrId)`, computed by the agent (`prepareConnectionLink'`, `newRcvConnSrv`) and the server (`createQueue`) | crypton; `C.sha3_384` | 48, truncated to 24 |
+| Keccak-256 | Restricted | Label hash for SMP name queries (`NameQuery NQHash`), must match the on-chain registry | crypton `Keccak_256`; `labelHash` in [SimplexName.hs](../src/Simplex/Messaging/SimplexName.hs) | 32 |
+| MD5 | Legacy-only, non-security | XOR-aggregated queue ID hash `IdsHash` for service subscription reconciliation (SUBS, NSUBS, SOKS, ENDS) | crypton (`C.md5Hash`, `Protocol.queueIdHash`); SQLite UDF `simplex_xor_md5_combine` ([Agent/Store/SQLite.hs](../src/Simplex/Messaging/Agent/Store/SQLite.hs)); PostgreSQL pgcrypto `digest(..., 'md5')` in server and NTF schemas | 16 |
+| ChaChaDRG | Default | Keys, nonces, correlation IDs, random IDs, sntrup761 randomness | crypton `Crypto.Random`; `C.newRandom` seeds with `drgNew` from system entropy | n/a |
+| BBS+ over BLS12-381, SHA-256 suite | Restricted | Badge entitlement credentials and proofs ([Crypto/Entitlement.hs](../src/Simplex/Messaging/Crypto/Entitlement.hs)), XFTP storage-time extension | Vendored submodules libbbs and blst (C and assembly) via FFI; randomness from libbbs `getentropy`, `SecRandomCopyBytes` with the `commoncrypto` flag, `BCryptGenRandom` on Windows ([cbits/getentropy_win.c](../cbits/getentropy_win.c)) | sk 32, pk 96, sig 80, proof 272 + 32 per undisclosed message |
+| ECDSA with SHA-256 (ES256) | Restricted | APNS provider JWT ([Push/APNS.hs](../src/Simplex/Messaging/Notifications/Server/Push/APNS.hs)) | crypton `Crypto.PubKey.ECC.ECDSA.sign`; key read by cryptostore `Crypto.Store.PKCS8`; curve taken from the key file | signature DER `SEQUENCE {r, s}`, base64url |
+| TLS 1.3 / 1.2 | Restricted | SMP, XFTP, NTF, XRCP transport: `TLS_CHACHA20_POLY1305_SHA256` (1.3), `ECDHE_ECDSA_CHACHA20POLY1305_SHA256` (1.2), groups X448 and X25519, Ed448 and Ed25519 signatures (`defaultSupportedParams`) | `tls` 1.9 | n/a |
+| TLS for browsers | Restricted | XFTP server with HTTPS credentials (`defaultSupportedParamsHTTPS`: `ciphersuite_strong`, FFDHE, P-521, ECDSA and RSA signatures); SMP server HTTPS requires RSA-4096 (`checkHTTPSCredentials`) | `tls`, `warp-tls` | n/a |
+| X.509 | Restricted | Certificate chains, fingerprints, signed session keys (`C.signX509`, `C.verifyX509`) | `crypton-x509`, `crypton-x509-validation`, `cryptostore` | n/a |
+| SQLCipher | Restricted | Agent SQLite database at rest (`PRAGMA key`); cipher parameters are SQLCipher defaults, not set in this repository | `direct-sqlcipher` (git dependency, [cabal.project](../cabal.project)) | n/a |
+
+## SimpleX box constructions
+
+`C.cryptoBox` and `LC.sbInit_` compute, for a 32-byte key `k` and 24-byte nonce `n`:
+
+```
+k1 = HSalsa20(k, 0^16)
+subkey = HSalsa20(k1, n[0..16])
+stream = Salsa20(subkey, n[16..24])
+polyKey = stream[0..32]
+ct = msg XOR stream[32..]
+tag = Poly1305(polyKey, ct)
+```
+
+| Construction | Key `k` | Equivalent libsodium call | Layout |
+|---|---|---|---|
+| SimpleX crypto_box (`C.cbEncrypt`, `LC.cbInit`) | X25519 shared secret | `crypto_box_easy` (`crypto_box_beforenm` is `HSalsa20(dh, 0^16)`) | strict: `tag \|\| ct`; lazy tail-tag: `ct \|\| tag` |
+| SimpleX secretbox (`C.sbEncrypt`, `LC.sbInit`, `KEM.kcb*`) | 32-byte symmetric key | `crypto_secretbox_easy` with key `crypto_core_hsalsa20(0^16, k)`, not with `k` | same |
+
+Padding before encryption: `C.pad` prefixes a 2-byte big-endian length and fills with `#` (message at most 65533 bytes); `LC.pad` prefixes an 8-byte length. `*NoPad` variants skip padding.
+
+## Domain separation and KDF inputs
+
+HKDF is `C.hkdf salt ikm info len` (HKDF-SHA512).
+
+| Info string | Salt | IKM | Output (split) | Function | Use |
+|---|---|---|---|---|---|
+| `"SimpleXX3DH"` | 64 zero bytes | `dh1 \|\| dh2 \|\| dh3 [\|\| kemShared]` | 96: `hk`, `nhk`, root key (32 each) | `CR.pqX3dh` | Ratchet initialization, added in E2E v2; KEM secret from E2E v3 (current minimum) |
+| `"SimpleXVerifyCode"` | 64 zero bytes | same as `SimpleXX3DH` | 32: `rcVCPQ` | `CR.pqX3dh` | Verification code covering all handshake keys, new ratchets |
+| `"SimpleXRootRatchet"` | root key | `dh [\|\| kemShared]` | 96: root key, chain key, next header key | `CR.rootKdf` | DH/PQ ratchet step |
+| `"SimpleXChainRatchet"` | empty | chain key | 96: chain key, message key (32 each), message IV (16), header IV (16) | `CR.chainKdf` | Per-message keys |
+| `"SimpleXSbChainInit"` | SMP session ID | X25519 session secret | 64: two 32-byte chain keys | `C.sbcInit` from `Transport.blockEncryption` | SMP transport block encryption, SMP v11+ |
+| `"SimpleXSbChainInit"` | empty | XRCP hybrid secret (below) | 64: two 32-byte chain keys | `C.sbcInit` in [RemoteControl/Client.hs](../src/Simplex/RemoteControl/Client.hs) | XRCP v1 session |
+| `"SimpleXSbChain"` | empty | chain key | 88: chain key (32), secretbox key (32), nonce (24) | `C.sbcHkdf` | Each SMP block and XRCP message |
+| `"SimpleXContactLink"` | empty | link key (32) | 56: link ID (24), secretbox key (32) | `SL.contactShortLinkKdf` | Contact short links, SMP v15+ |
+| `"SimpleXInvLink"` | empty | link key (32) | 32: secretbox key | `SL.invShortLinkKdf` | Invitation short links, SMP v15+ |
+
+Other derivations:
+
+| Value | Construction | Function | Use |
+|---|---|---|---|
+| Service request binding | `sha3_256("SimpleXService" \|\| rcAD)` | `serviceReqBinding` in [Agent.hs](../src/Simplex/Messaging/Agent.hs) | Agent RPC, agent v8 |
+| BBS header | `"SimpleX badges v1"` | `entitlementBBSHeader` | Badge credentials |
+| XRCP hybrid secret | `sha3_256(x25519Dh \|\| kemShared)` | `KEM.kemHybridSecret` | XRCP v1 |
+| Short-link key | `sha3_256(smpEncode FixedLinkData)` | `SL.encodeSignFixedData`, checked in `SL.decryptLinkData` | SMP v15+ |
+| Sender ID | `take 24 (sha3_384 corrId)` | `prepareConnectionLink'`, `newRcvConnSrv` in Agent.hs; `createQueue` in [Server.hs](../src/Simplex/Messaging/Server.hs) | Client-supplied sender ID with link data, SMP v15+; the server rejects a mismatch to prevent an ID oracle |
+| Ratchet associated data | `pubKeyBytes sk1 \|\| pubKeyBytes rk1` (raw X448, 112) | `CR.pqX3dh` | AD of every ratchet AEAD |
+| Security code | `sha256(rcAD)` | `ratchetVerifyCodes` in [AgentStore.hs](../src/Simplex/Messaging/Agent/Store/AgentStore.hs) | Connection verification |
+| Contact request code | `sha256(smpEncode (k1, k2, kem, sndId))` | `requestCode` in Agent.hs | Contact request binding |
+| Command authenticator | `crypto_box(sha512(authorized))` | `C.cbAuthenticate` | SMP v7+ |
+| Queue IDs hash | `xor` of `md5(queueId)` | `Protocol.queueIdsHash` | Service subscriptions |
+
+`"SimpleXSbChainInit"` and `"SimpleXSbChain"` are shared by SMP block encryption and XRCP. Their outputs are separated only by the IKM (and the salt for `sbcInit`).
+
+## Nonces and IVs
+
+| Use | Construction |
+|---|---|
+| SMP command authenticator, proxied command | `C.cbNonce corrId`, where `corrId` is a random 24-byte nonce (`C.randomCbNonce`) |
+| SMP proxied responses | `C.reverseNonce` of the request nonce |
+| Server-to-recipient message body | `C.cbNonce msgId`; `msgIdBytes = 24` in [Server/Main.hs](../src/Simplex/Messaging/Server/Main.hs) |
+| Per-queue e2e envelope, short-link data, notifications, XRCP hello, XFTP chunk download | Random 24-byte nonce, sent with the ciphertext |
+| XFTP file, local encrypted file | Random key and nonce per file (`C.randomSbKey`, `C.randomCbNonce`) |
+| SMP block, XRCP session messages | Key and nonce from `C.sbcHkdf`, one per block |
+| Ratchet header, body | 16-byte IVs from `CR.chainKdf`; header IV is sent, body IV is not |
+| WebRTC frames | 12-byte `C.GCMIV` supplied by the caller in simplex-chat |
+
+## Implementation sources
+
+| Source | Version or pin | Provides |
+|---|---|---|
+| crypton | 0.34 | Ed25519, Ed448, X25519, X448, XSalsa20, Poly1305, AES-GCM, HKDF, SHA-2, SHA-3, Keccak, MD5, ChaChaDRG, ECDSA |
+| tls, crypton-x509, crypton-x509-validation, cryptostore | 1.9.0, 1.7.6, 1.6.12, 0.3.0.1 | TLS, X.509, PKCS#8 |
+| [cbits/sntrup761.c](../cbits/sntrup761.c) | Copy of draft-josefsson-ntruprime-streamlined-00 ([cbits/README.md](../cbits/README.md)) | sntrup761 |
+| [cbits/sha512.c](../cbits/sha512.c) and system OpenSSL `libcrypto` | system | SHA-512 for sntrup761 |
+| `cbits/libbbs` submodule ([simplex-chat/libbbs](https://github.com/simplex-chat/libbbs)) | `59a0f4bf` | BBS+ (`bbs_sha256_ciphersuite`), SHA-256, SHAKE256 |
+| `cbits/blst` submodule ([supranational/blst](https://github.com/supranational/blst)) | `db3defd0` | BLS12-381 (C and `build/assembly.S`, `-D__BLST_PORTABLE__`) |
+| direct-sqlcipher | git `f814ee68` | SQLCipher |
+| `openssl` CLI | system | Server CA and certificate key generation (`createServerX509_`) |
+
+## xftp-web (TypeScript)
+
+[xftp-web](../xftp-web/) reimplements a subset for the browser XFTP client. It has no AES-GCM, HKDF, SHA-3, MD5, X448 or sntrup761 code.
+
+| Primitive | Implementation | Haskell counterpart |
+|---|---|---|
+| Ed25519 sign, verify, keys | libsodium-wrappers-sumo (`crypto_sign_*`), [src/crypto/keys.ts](../xftp-web/src/crypto/keys.ts) | `C.sign'`, `C.verify'` |
+| Ed448 verify | `@noble/curves/ed448`, keys.ts `verifyEd448` | `C.verify'` |
+| X25519 | libsodium `crypto_scalarmult`, `crypto_box_keypair` | `C.dh'` |
+| SimpleX crypto_box, secretbox, tail-tag streaming | Salsa20 block function written in TypeScript, libsodium `crypto_core_hsalsa20` and `crypto_onetimeauth_*`, [src/crypto/secretbox.ts](../xftp-web/src/crypto/secretbox.ts) | `C.cryptoBox`, `LC.sbInit_` |
+| crypto_box authenticator | [src/protocol/client.ts](../xftp-web/src/protocol/client.ts) `cbAuthenticate`, `cbVerify` | `C.cbAuthenticate`, `C.cbVerify` |
+| SHA-256, SHA-512 | libsodium `crypto_hash_sha256`, `crypto_hash_sha512*`, [src/crypto/digest.ts](../xftp-web/src/crypto/digest.ts) | `C.sha256Hash`, `C.sha512Hash` |
+| Random | WebCrypto `crypto.getRandomValues`; libsodium for key generation | `C.randomBytes` |
+
+## Tests
+
+None of the tests below compares against published reference vectors (NIST, RFC 8032, RFC 7748, RFC 5869, NaCl, the sntrup761 draft or the BBS draft). Interoperability is tested between this repository's own implementations.
+
+| Area | Test module (hspec group) | Kind |
+|---|---|---|
+| Ed25519, Ed448, X25519 crypto_box, secretbox, lazy and tail-tag secretbox, AES-GCM 12-byte IV, X.509 key encoding, X.509 chains, sntrup761, BBS+, entitlements, padding | [tests/CoreTests/CryptoTests.hs](../tests/CoreTests/CryptoTests.hs) | Round-trip; fixed lengths for BBS+; fixed bytes for padding |
+| Double ratchet (X25519 and X448), PQ KEM agreement, AES-GCM 16-byte IV | [tests/AgentTests/DoubleRatchetTests.hs](../tests/AgentTests/DoubleRatchetTests.hs) | Round-trip; decoding of a stored v2 ratchet JSON |
+| Short links (HKDF info strings, SHA3-256 link key) | [tests/AgentTests/ShortLinkTests.hs](../tests/AgentTests/ShortLinkTests.hs) | Round-trip, tamper rejection |
+| File encryption | [tests/CoreTests/CryptoFileTests.hs](../tests/CoreTests/CryptoFileTests.hs) | Round-trip |
+| XRCP session (SHA3-256 hybrid, sb chain) | [tests/RemoteControl.hs](../tests/RemoteControl.hs) | End-to-end |
+| SMP authenticators, block encryption, `IdsHash` (MD5) | [tests/ServerTests.hs](../tests/ServerTests.hs) | End-to-end; with the PostgreSQL queue store this checks Haskell MD5 against pgcrypto |
+| Haskell and xftp-web: SHA-256/512, Ed25519, Ed448 identity proof, X25519, DER keys, crypto_box, secretbox, tail-tag, authenticator, file encryption | [tests/XFTPWebTests.hs](../tests/XFTPWebTests.hs) (`XFTP Web Client`) | Byte-identical cross-language output |
@@ -17,11 +17,11 @@ note over CC, HC: TLS handshake
 par
    note over CC: validate client X509 credentials
    CC->>CI: session code from tlsUnique
-    CI-->>CC: user confirmation
+    CI-->>CC: user confirmation (optional if known)
 and
    note over HC: validate server X509 credentials
    HC->>HI: session code from tlsUnique
-    HI-->>HC: user confirmation
+    HI-->>HC: user confirmation (optional if known)
 end

 note over CI, HI: 3. Session verification and protocol negotiation
@@ -62,14 +62,16 @@ It is possible to reduce size overhead by using only one KEM agreement and makin

 ## Double ratchet with encrypted headers augmented with double PQ KEM

-Algorithm below assumes that in addition to shared secret from the initial key agreement, there will be an encapsulation key available from the party that published its keys (Bob).
+Algorithm below assumes that in addition to shared secret from the initial key agreement, there will be an encapsulation key available from the initiating party, that sent its keys in the connection invitation to the joining party (see [agent protocol](./agent-protocol.md)). Following the double ratchet specification, the pseudo-code below names the joining party Alice and the initiating party Bob.
+
+Unlike X3DH prekey bundles, these keys are not reusable keys published for any party to use. The initiating party generates two X448 key pairs and, optionally, a sntrup761 KEM key pair for each connection, sends the public keys in the invitation, and deletes the stored private keys once the ratchet is initialized; only the second X448 private key and the agreed KEM key pair remain in the ratchet state as its initial ratchet keys. The joining party generates its keys when joining and keeps only its KEM key pair, in the ratchet state. The exception is a contact address that publishes ratchet keys in its link data: all requesters use these keys until the address owner rotates them, and the owner keeps the private keys of a few recent generations.

 ### Initialization

 The double ratchet initialization is defined in pseudo-code. This pseudo-code is identical to Signal algorithm specification except for that parts that add post-quantum key agreement.

 ```
-// Alice obtained Bob's keys and initializes ratchet first
+// Alice (joining party) received Bob's keys in the invitation and initializes ratchet first
 def RatchetInitAlicePQ2HE(state, SK, bob_dh_public_key, shared_hka, shared_nhkb, bob_pq_kem_encapsulation_key):
    state.DHRs = GENERATE_DH()
    state.DHRr = bob_dh_public_key
@@ -89,7 +91,7 @@ def RatchetInitAlicePQ2HE(state, SK, bob_dh_public_key, shared_hka, shared_nhkb,
    state.HKr = None
    state.NHKr = shared_nhkb

-// Bob initializes ratchet second, having received Alice's connection request
+// Bob (initiating party) initializes ratchet second, having received Alice's first message
 def RatchetInitBobPQ2HE(state, SK, bob_dh_key_pair, shared_hka, shared_nhkb, bob_pq_kem_key_pair):
    state.DHRs = bob_dh_key_pair
    state.DHRr = None
@@ -210,6 +212,8 @@ The outer envelope contains the encrypted header (used as associated data for bo

 The message body is encrypted with AES-256-GCM using the message key derived from the sending chain key (`KDF_CK`). The associated data for body encryption is the concatenation of the ratchet associated data and the encoded encrypted header.

+`KDF_CK(CK)` is HKDF-SHA512 with empty salt, `CK` as input key material and info `"SimpleXChainRatchet"`, producing 96 bytes split into the next chain key (32 bytes), the message key (32 bytes), the message body IV (16 bytes, not transmitted) and `headerIV` (16 bytes). Both IVs are used as 16-byte AES-256-GCM IVs, not the 12-byte IVs recommended by NIST SP 800-38D, so the initial counter block is J0 = GHASH(IV || 0^64 || [128]_64) as defined there for non-96-bit IVs. WebCrypto and other conforming implementations compute it when given the full 16-byte IV; truncating the IV to 12 bytes produces different ciphertext.
+
 ```abnf
 encRatchetMessage = versionedLength encMessageHeader msgAuthTag encMsgBody
 ; encMessageHeader is used as associated data for body decryption: AD = rcAD || encMessageHeader
@@ -274,7 +278,7 @@ As SimpleX Messaging Protocol pads messages to a fixed size, using 16kb transpor

 Sharing the initial keys in case of SimpleX Chat it is equivalent to sharing the invitation link. As encapsulation key is large, it may be inconvenient to share it in the link in some contexts, e.g. when QR codes are used.

-It is possible to postpone sharing the encapsulation key until the first message from Alice (confirmation message in SMP protocol), the party sending connection request. The upside here is that the invitation link size would not increase. The downside is that the user profile shared in this confirmation will not be encrypted with PQ-resistant algorithm.
+It is possible to postpone sharing the encapsulation key until the first message from the joining party (confirmation message in SMP protocol). The upside here is that the invitation link size would not increase. The downside is that the user profile shared in this confirmation will not be encrypted with PQ-resistant algorithm.

 Another consideration is pairwise ratchets in groups. Key generation in sntrup761 is quite slow - on slow devices it can be as slow as 10-20 keys per second, so using this primitive in groups larger than 10-20 members would result in slow performance.

@@ -1,12 +1,11 @@
-Version 4, 2026-09-11
+Version 3, 2025-01-24

 # Overview of push notifications for SimpleX Messaging Routers

-This document describes Notification Router protocol version 4. Version history:
+This document describes Notification Router protocol version 3. Version history:
 - v1: initial version
 - v2: authenticated commands, command batching
 - v3: detailed invalid token reason
- v4: entitlement proof in client handshake

 ## Table of contents

@@ -95,7 +94,7 @@ This diagram shows the process of subscription to notifications, notification de

 To manage notification subscriptions to SMP routers, SimpleX Notification Router provides an RPC protocol with a similar design to SimpleX Messaging Protocol router.

-This protocol sends requests and responses in a fixed size blocks of 512 bytes over TLS, uses the same [syntax of protocol transmissions](./simplex-messaging.md#smp-transmission-and-transport-block-structure) as SMP protocol, and has the same transport [handshake syntax](./simplex-messaging.md#transport-handshake) (except the router certificate is not included in the handshake). The client handshake carries the protocol version, the router key hash and, from v4, the optional `entitlementProof` with the same syntax and session binding as in SMP.
+This protocol sends requests and responses in a fixed size blocks of 512 bytes over TLS, uses the same [syntax of protocol transmissions](./simplex-messaging.md#smp-transmission-and-transport-block-structure) as SMP protocol, and has the same transport [handshake syntax](./simplex-messaging.md#transport-handshake) (except the router certificate is not included in the handshake).

 The client and router use ALPN extension with `ntf/1` protocol name to agree handshake version.

@@ -15,7 +15,7 @@ This document describes the cryptographic primitives and threat model for the Si
  - [SimpleX Messaging Protocol router that proxies the messages to another SMP router](#simplex-messaging-protocol-router-that-proxies-the-messages-to-another-smp-router)
  - [An attacker who obtained Alice's (decrypted) chat database](#an-attacker-who-obtained-alices-decrypted-chat-database)
  - [A user's contact](#a-users-contact)
-  - [An attacker who observes Alice showing an introduction message to Bob](#an-attacker-who-observes-alice-showing-an-introduction-message-to-bob)
+  - [An attacker who observes the initiating party showing an introduction message to the joining party](#an-attacker-who-observes-the-initiating-party-showing-an-introduction-message-to-the-joining-party)
  - [An attacker with Internet access](#an-attacker-with-internet-access)


@@ -37,6 +37,8 @@ This document describes the cryptographic primitives and threat model for the Si
  - AES-GCM AEAD cipher,
  - SHA512-based HKDF for key derivation.

+All primitives in use, their lengths, domain-separation strings and the policy for new code are listed in the [cryptographic primitive registry](./crypto-registry.md).
+

 ## Threat Model

@@ -168,7 +170,7 @@ This document describes the cryptographic primitives and threat model for the Si

 *cannot:*

- impersonate a sender and send messages to the user whose database was stolen. Doing so requires also compromising the router (to place the message in the queue, that is possible until the Double-Ratchet advances forward) or the user's device at a subsequent time (to place the message in the database).
+- impersonate a sender and send messages to the user whose database was stolen, unless the database contains a new rotation queue that is not secured yet. Doing so requires also compromising the router (to place the message in the queue, that is possible until the Double-Ratchet advances forward) or the user's device at a subsequent time (to place the message in the database).

 - undetectably communicate at the same time as Alice with her contacts. Doing so would result in the contact getting different messages with repeated IDs.

@@ -190,15 +192,15 @@ This document describes the cryptographic primitives and threat model for the Si

 - cannot collaborate with another of the user's contacts to confirm they are communicating with the same user.

-### An attacker who observes Alice showing an introduction message to Bob
+### An attacker who observes the initiating party showing an introduction message to the joining party

 *can:*

- Impersonate Bob to Alice.
+- Impersonate the joining party to the initiating party.

 *cannot:*

- Impersonate Alice to Bob.
+- Impersonate the initiating party to the joining party.

 ### An attacker with Internet access

@@ -109,7 +109,7 @@ This document describes SMP protocol version 23. Versions 1-5 are discontinued.
 - v20: public namespaces resolver (RSLV command, RNAME response) — direct or forwarded via PFWD
 - v21: server public information in handshake
 - v22: `RNAME` says whether a name can be registered, not only what it resolves to
- v23: entitlement proof in client handshake
+- v23: version in nonces of forwarded commands, random nonces for forwarded responses

 ## Introduction

@@ -1121,13 +1121,15 @@ When the client receives PKEY response it MUST validate that:
 - the fingerprint of the received certificate matches fingerprint in the router address - it mitigates MITM attack by proxy.
 - the router session key is correctly signed with the received certificate.

+`smpVersionRange` in `PKEY` is not signed.
+
 The proxy router may respond with error response in case the destination router is not available or in case it has an earlier version that does not support proxied commands.

 #### Send command via proxy

 Sender can send `SKEY` and `SEND` commands via proxy after obtaining the session ID with `PRXY` command (see [Request proxied session](#request-proxied-session)).

-Transmission sent to proxy router should use session ID as entity ID and use a random correlation ID of 24 bytes as a nonce for crypto_box encryption of transmission to the destination router. The random ephemeral X25519 key to encrypt transmission should be unique per command, and it should be combined with the key sent by the router in the handshake header to proxy and to the client in `PKEY` command.
+Transmission sent to proxy router should use session ID as entity ID and use a random correlation ID of 24 bytes as a nonce for crypto_box encryption of transmission to the destination router. When `smpVersion` in `PFWD` is 23 or higher, the first 2 bytes of this nonce are XOR-ed with `smpVersion`. The random ephemeral X25519 key to encrypt transmission should be unique per command, and it should be combined with the key sent by the router in the handshake header to proxy and to the client in `PKEY` command.

 Encrypted transmission should use the received session ID from the connection between proxy router and destination router in the authorized body.

@@ -1139,10 +1141,11 @@ commandKey = length x509encoded

 The proxy router will forward the encrypted transmission in `RFWD` command (see below).

-Having received the `RRES` response from the destination router, proxy router will forward `PRES` response to the client. `PRES` response should use the same correlation ID as `PFWD` command. The destination router will use this correlation ID increased by 1 as a nonce for encryption of the response.
+Having received the `RRES` response from the destination router, proxy router will forward `PRES` response to the client. `PRES` response should use the same correlation ID as `PFWD` command. The destination router will use this correlation ID increased by 1 as a nonce for encryption of the response. When `smpVersion` in `PFWD` is 23 or higher, the destination router uses a random nonce instead, and sends it before the encrypted response.

 ```abnf
-proxyResponse = %s"PRES" SP <encrypted padded(forwardedResponse, 16226)>
+proxyResponse = %s"PRES" SP [responseNonce] <encrypted padded(forwardedResponse, 16226)>
+responseNonce = %s"0" / (%s"1" 24*24 OCTET) ; from v23
 forwardedResponse = *OCTET ; client-encrypted SMP response, decrypted by client using per-command DH secret
 ```

@@ -1169,7 +1172,7 @@ The shared secret for encrypting transmission bodies between proxy router and de


 ```abnf
-relayResponse = %s"RRES" SP <encrypted(responseTransmission)>
+relayResponse = %s"RRES" SP [responseNonce] <encrypted(responseTransmission)>
 responseTransmission = fwdCorrId forwardedResponse
  ; fwdCorrId and forwardedResponse defined above in RFWD section
 ```
@@ -1714,7 +1717,7 @@ cert = originalLength x509encoded
 signedRouterKey = originalLength x509encoded ; X25519 key signed by router certificate

 paddedClientHello = <padded(clientHello, 16384)>
-clientHello = smpVersion keyHash [clientKey] proxyRouter optClientService optEntitlementProof ignoredPart
+clientHello = smpVersion keyHash [clientKey] proxyRouter optClientService ignoredPart
 ; chosen SMP protocol version - it must be the maximum supported version
 ; within the range offered by the router
 keyHash = shortString ; router identity - CA certificate fingerprint
@@ -1726,21 +1729,7 @@ serviceRole = %s"M" / %s"N" / %s"P" ; Messaging / Notifier / Proxy
 serviceCertKey = certChain signedServiceKey
 signedServiceKey = originalLength x509encoded ; Ed25519 key signed by service certificate

-optEntitlementProof = %s"0" / (%s"1" entitlementProof)
-; proof of the user entitlement, encoded from v23, bound to sessionIdentifier
-entitlementProof = issuerKeyIndex bbsProof entitlement
-issuerKeyIndex = 2*2OCTET ; Word16 index of the issuer public key
-bbsProof = largeString
-entitlement = entExpires entName entExtra
-entExpires = shortString ; expiration as an ISO8601 UTC timestamp
-entName = shortString ; e.g. "supporter", "legend"
-entExtra = largeString ; opaque to the router
-
 smpVersion = 2*2OCTET ; Word16 version number
-shortString = length *OCTET
-largeString = length2 *OCTET
-length = 1*1OCTET
-length2 = 2*2OCTET ; Word16, network byte order
 originalLength = 2*2OCTET
 count = 1*1OCTET
 ignoredPart = *OCTET
@@ -1762,8 +1751,6 @@ serviceId = shortString
 handshakeError = transportError
 ```

-`entitlementProof` (v23+) presents the entitlement of the user - its name, expiration and an opaque extra string - as the disclosed content of a BBS proof over the presentation header `sessionIdentifier`, so a proof presented on another session does not verify. The holder secret and the issuer signature remain with the client. Clients send it only to their own routers, identified by the key hash pinned in TLS.
-
 `ignoredPart` in handshake allows to add additional parameters in handshake without changing protocol version - the client and routers must ignore any extra bytes within the original block length.

 For TLS transport client should assert that `sessionIdentifier` is equal to `tls-unique` channel binding defined in [RFC 5929][14] (TLS Finished message struct); we pass it in `routerHello` block to allow communication over some other transport protocol (possibly, with another channel binding).
@@ -71,7 +71,7 @@ The session invitation contains this data:

 Host application decrypts (except the first session) and validates the invitation:
 - Session signature is valid.
- Timestamp is within some window from the current time.
+- Timestamp of a multicast announcement is not earlier than 3660 seconds before and not later than 3600 seconds after the current time of the host. The host ignores announcements outside of this interval and continues listening.
 - Long-term key signature is valid.
 - Long-term CA and signature key are the same as in the first session.
 - Some version in the offered range is supported.
@@ -121,9 +121,15 @@ During TLS handshake, parties validate certificate chains against previously kno

 ### Session verification and protocol negotiation

-Once TLS session is established, both the host and controller devices present a "session security code" to the user who must match them (e.g., visually or via QR code scan) and confirm on the host device. The session security code must be a digest of tlsunique channel binding. As it is computed as a digest of the TLS handshake for both the controller and the host, it will validate that the same TLS certificates are used on both sides, and that the same TLS session is established, mitigating the possibility of MITM attack in the connection.
+Once TLS session is established, both the host and controller devices present a "session security code" to the user. The session security code must be a digest of tlsunique channel binding. As it is computed as a digest of the TLS handshake for both the controller and the host, it will validate that the same TLS certificates are used on both sides, and that the same TLS session is established, mitigating the possibility of MITM attack in the connection.

-Once the session is confirmed by the user, the host sends HELLO block to the controller.
+To verify the session, the user matches the codes (e.g., visually or via QR code scan) and confirms the session on the host device.
+
+The user MUST verify the first session with a new controller. The host stores the long-term identity of the controller (CA fingerprint and Ed25519 public key) only after this session is verified. A controller with the stored long-term identity is a known controller.
+
+The user MAY verify the subsequent sessions with a known controller. In a session that the host confirms without user action, the controller is authenticated only by its long-term identity stored in the first session (see [Threat model](#threat-model)). SimpleX Chat mobile apps require user verification of sessions with known controllers only when the user enables the "Verify connections" option.
+
+Once the session is confirmed, the host sends HELLO block to the controller.

 XRCP blocks inside TLS are padded to 16384 bytes.

@@ -305,7 +311,7 @@ to receive: (rcvKey', sk, nonce) = HKDF(rcvKey, "SimpleXSbChain", 88)
 - prevent host and controller devices from establishing the session

 *cannot:*
- same as passive adversary, provided that user visually verified session code out-of-band.
+- same as passive adversary, provided that user visually verified session code out-of-band in the first session with the controller.

 #### An active adversary with the access to the network:

@@ -324,6 +330,15 @@ to receive: (rcvKey', sk, nonce) = HKDF(rcvKey, "SimpleXSbChain", 88)
 *cannot:*
 - connect to the host or make host connect to itself.

+#### An active adversary with the access to the network who also obtained the long-term private keys of a known controller (e.g., from the controller device):
+
+*can:*
+- make host connect to itself instead of the controller.
+- access any data of the controlled host application, within the capabilities of the provided API, if the host confirms the session without user action.
+
+*cannot:*
+- access host application data, provided that user visually verified session code out-of-band.
+
 #### Compromised controller device:

 *can:*
@@ -1,422 +0,0 @@
-# Proof of work for resource creation
-
-## Summary
-
-A client presents a proof of work when it asks a server to create a resource: an SMP queue, an XFTP file chunk, a notification token. The required effort is the price of the resource: its cost in units multiplied by the price per unit.
-
-The server sets one price per unit for each tier: sessions without an entitlement, and sessions of each entitlement name. The prices are independent, so a flood in one tier raises the price of that tier alone.
-
-The proof is bound to the transport session, so it is valid on one connection to one server, and single use within it.
-
-## Interaction
-
-The exchange adds no round trip. The server handshake states the prices and the server time, the session id is the challenge input that both sides already hold, and the client attaches a proof to the command that creates the resource.
-
-Nothing is sent back for the price alone: it rides the messages that already exist.
-
-## Freshness
-
-A proof states the minute it was made for, and expires after a few minutes.
-
-Without an expiry a client mints proofs for as long as a session lasts and spends the stock in one burst. The stock is minted at the idle price, so a rising price reaches the burst after it lands, and an hour of one machine arrives in seconds. The expiry bounds the stock to the work of one window.
-
-```
-powEpoch = 4*4 OCTET    ; Word32, minutes of server time
-```
-
-The server sends its current epoch in the handshake, and the client counts minutes from it with a monotonic clock, so the clock of the device takes no part. A proof verifies while `serverEpoch - powEpoch` is within the advertised window, and one epoch ahead of the server is admitted for rounding.
-
-The window is the burst a client may prepare: a stock of `window * mint rate`. At 5 minutes and a price of 16, one desktop core holds about 2800 queue proofs.
-
-A price increase cuts the stock a second way. A proof states the effort it was made for, so every proof below the new price is rejected, and the stock of an attacker survives an increase only at the effort it paid for in advance. The two bounds compose: the stock is worth the smaller of one window of minting and the time until the next increase.
-
-## What Tor does
-
-Tor proposal 327 and the [hspow specification](https://spec.torproject.org/hspow-spec/) define a client puzzle for onion service introduction.
-
- Function: Equi-X (Equihash(60,3) over HashX) with a Blake2b target check. Solution 16 bytes, solver memory 1.8 MiB, verification 50-120 microseconds.
- Effort: a 32-bit number `E`. The solution passes when `R * E <= UINT32_MAX`, where `R` is the first 32 bits of `blake2b_32(challenge || S)`. `E` is the expected number of candidate solutions tested, so cost is linear in `E`.
- Challenge: `P || ID || C || N || htonl(E)` - personalisation, service identity, a 32-byte seed from the service descriptor, a 16-byte nonce, effort.
- Freshness: the service publishes a seed in its descriptor and rotates it every 105-120 minutes, keeps the previous seed, and holds a replay cache of used `(seed, nonce)` pairs.
- Selection: verified requests enter a priority queue ordered by effort. Overfull queues discard the lower-effort half.
- Adaptation: every 300 seconds the service updates `suggested-effort` by additive increase and multiplicative decrease. Increase to `max(previous + 1, TOTAL_EFFORT / REND_HANDLED)` when the queue was congested or when a trimmed request exceeded the current effort; multiply by `2/3` when the queue stays short. The value is published in the descriptor.
- Client retry: on timeout, refetch the descriptor, then double the effort below 1000, multiply by 1.5 above it, within [8, 10000].
-
-Tor solves a reachability problem: many clients compete for one bottleneck, so they bid and the service serves the highest bids.
-
-## What we change
-
-Our problem is the price of a stored resource, so the auction is replaced by a price list.
-
-1. Threshold, not bidding. The server states the required effort; the client sends exactly that. The priority queue and its trimming are dropped. A faster device gains no priority, so the effort value describes the request rather than the device.
-2. Session binding, not seeds. The challenge includes the hash of the transport session id, which both sides already hold. This removes seed generation, seed rotation, seed publication, and the two-seed overlap.
-3. Single use by a counter, not by a replay cache. Each proof carries a session counter, and the server keeps the highest counter it accepted plus a 64-bit window of the counters below it. Per-session state is 16 bytes, against 16 bytes per accepted proof for a set of nonces. Tor needs the set because one seed spans many connections; a proof here is valid on one connection only.
-4. An expiry of minutes, against the seed window of two hours in Tor. A stock of proofs is worth one window of minting, so a price increase reaches a burst that was prepared under the old price.
-5. Prices set by the operator. Effort is the resource cost in units multiplied by the price per unit, and the operator sets the price. The estimator of Tor is deferred.
-6. One price per tier. The server knows the tier of every session, so a flood shows in its tier, and raising that price leaves the other tiers unchanged. An attacker without a badge leaves the price of badge holders where it was; an attacker with a supporter badge leaves the price of legend holders where it was.
-7. An entitlement lowers the price, and neither raises it nor removes it. A credential presents on any number of sessions without linking them, so a free tier would sell an attacker unlimited creation for the price of one badge; and a badge that could cost more than no badge would break the promise it was sold with, the promise the XFTP server keeps for storage time.
-8. A budget for clients of earlier versions, where Tor serves them at the lowest priority. They cannot pay, so they share a number of creations per minute.
-
-Kept from Tor: the Equi-X function, the linear effort scale, the verification formula, and the exact byte definitions of the target check.
-
-## Cost units
-
-Each protocol defines the unit of its own price list. The server advertises the price per unit; the client computes the effort of its request.
-
-```
-SMP:  1 unit per new queue
-      1 unit per queue link data record (in NEW, or in LSET on a queue without one)
-XFTP: 1 unit per 64 KB stored for 24 hours
-      chunkUnits = ceil(size / 65536 * storageHours / 24)
-      storageHours = min(requested hours, maximum hours of the tier); absent or 0 = the maximum
-NTF:  1 unit per token registration
-```
-
-`effort = price * units`, capped at 2^32 - 1.
-
-64 KB is the smallest chunk. The server takes chunks of 64 KB, 256 KB, 1 MB and 4 MB, and the test configuration adds 128 KB; each is a whole number of units.
-
-## Handshake parameters
-
-Each protocol adds one optional field to the server handshake, encoded from the version that introduces proof of work.
-
-```
-powParams = %s"0" / (%s"1" powScheme defaultPrice entPrices serverEpoch epochWindow)
-powScheme = 1*1 OCTET        ; 1 = Equi-X and Blake2b
-defaultPrice = tierPrice     ; without an entitlement; price 0 = proof not required
-entPrices = count *entPrice
-entPrice = entName tierPrice
-entName = shortString        ; entitlement name, as in the entitlement proof
-serverEpoch = 4*4 OCTET      ; Word32, current minute of server time
-epochWindow = 1*1 OCTET      ; minutes a proof stays valid
-
-SMP, NTF:  tierPrice = price
-XFTP:      tierPrice = price storageHours
-price = 4*4 OCTET            ; Word32, effort per unit
-storageHours = 4*4 OCTET     ; Word32, maximum storage time of the tier
-```
-
-The server handshake precedes the client handshake that carries the entitlement proof, so every price is sent. The client applies the price of its entitlement name, and the default price when it presented no entitlement or when its name is absent from the list.
-
-The XFTP client learns the maximum storage time of its tier from the same entry, so it computes the units of a chunk that asks for the maximum. The grant in `SIDS` stays as it is.
-
-## Algorithm
-
-Equi-X, by tevador, is Equihash(60,3) with two changes: the hash is HashX, and the indices are summed modulo 2^60 rather than xored.
-
-HashX takes a seed - here the challenge - and generates a short program of integer instructions over eight 64-bit registers, which maps a 64-bit input to a 64-bit output. The program differs for every seed, so hardware built for one program serves no other. That is where the resistance to an ASIC comes from, and what narrows the distance to a GPU.
-
-HashX runs the program in one of two modes. Compiled, it writes machine code for x86-64 or arm64 into executable memory, and hashes in under 100 nanoseconds. Interpreted, it hashes in 1-2 microseconds. Our clients take the interpreter on every platform: iOS refuses executable memory to App Store apps, GrapheneOS stops an Android app that loads code at run time, and desktop clients follow the phones. An attacker enables the compiler with one flag, `EQUIX_CTX_COMPILE`, or runs the benchmark of tevador as it is.
-
-Solving finds eight 16-bit indices `i0..i7` with `HX(i0) + ... + HX(i7) = 0 (mod 2^60)`, under the tree conditions of Wagner's algorithm - 15 trailing zero bits on each pair, 30 on each quadruple, 60 on the sum - and an ordering condition that makes the solution canonical. The solver holds tables over 2^16 items, which is the 1.8 MiB. A solution is `8 * uint16`, so 16 bytes, and one call returns about two of them.
-
-Verification recomputes the eight HashX values and checks the three sums. It takes 50-120 microseconds and a few kilobytes.
-
-The protocol layer above it is the target check: a solution counts when `blake2b_32(challenge || solution) * effort <= 2^32 - 1`. Finding a solution is the constant cost; landing one in a slice of `1/effort` is the price. Expected solver calls are `effort / 2`, and expected tested solutions are `effort`.
-
-## Code
-
-```
-C, the reference:  https://github.com/tevador/equix   LGPL-3.0, hashx as its submodule
-                   https://github.com/tevador/hashx   LGPL-3.0
-Rust, the port:    arti crates equix 0.7.1, hashx 0.9.1, LGPL-3.0-only
-Tor, in use:       src/ext/equix (vendored), src/feature/hs/hs_pow.c and hs_pow.h
-```
-
-The library is a git submodule at `cbits/equix`, from a fork under simplex-chat, as `cbits/libbbs` is today; hashx comes in as its nested submodule. The fork starts from tevador's repository, after a comparison with the copy in Tor for fixes. The C sources are listed in `c-sources`, and the Haskell side is a foreign import of the four calls below.
-
-```c
-equix_ctx* equix_alloc(equix_ctx_flags flags);  /* EQUIX_CTX_SOLVE | EQUIX_CTX_COMPILE, or EQUIX_CTX_VERIFY */
-int equix_solve(equix_ctx* ctx, const void* challenge, size_t size, equix_solution out[8]);
-equix_result equix_verify(equix_ctx* ctx, const void* challenge, size_t size, const equix_solution* sol);
-void equix_free(equix_ctx* ctx);
-```
-
-A context holds the program generated for the current challenge, so each thread allocates its own: one per solver thread on the client, a small pool on the server. Clients allocate without `EQUIX_CTX_COMPILE`.
-
-`hs_pow.c` is the closest model for our code: `build_equix_challenge` and `validate_equix_challenge` are the two functions we reimplement with our own challenge, `hs_pow_solve` is the search loop, `hs_pow_verify` is the order of checks, and `hs_pow_queue_work` runs solving on the worker pool at low priority.
-
-The licence is LGPL-3.0 for both implementations. Our library is AGPL-3.0, so linking asks nothing new of us, while a closed-source consumer of the library acquires the obligations of the LGPL for that part.
-
-## Proof
-
-```
-proofOfWork = powEffort powEpoch powNonce powSolution
-powEffort = 4*4 OCTET      ; Word32, the effort this proof was made for
-powEpoch = 4*4 OCTET       ; Word32, the minute of server time this proof was made for
-powNonce = powCounter powSearch
-powCounter = 4*4 OCTET     ; Word32, the counter of this proof in the session
-powSearch = 12*12 OCTET    ; the value the solver varies
-powSolution = 16*16 OCTET  ; Equi-X solution
-```
-
-40 bytes.
-
-```
-challenge = personalisation sessionHash htonl(powEffort) htonl(powEpoch) powNonce
-personalisation = 16*16 OCTET  ; "SimpleX PoW v1 " and one of %s"S" / %s"X" / %s"N"
-sessionHash = 32*32 OCTET      ; sha256 of the transport session id
-```
-
-The client picks the next counter and a random search value, calls `equix_solve(challenge)`, computes `R = ntohl(blake2b_32(challenge || S))`, and accepts the solution when `R * E <= 2^32 - 1`, computed in 64 bits. Otherwise it increments the search value as a little-endian integer and repeats.
-
-```
-S = packed solution         ; 8 indices, each a little-endian uint16, 16 bytes
-blake2b_32 = BLAKE2b initialised with a 4-byte output length
-R = the 4 bytes of blake2b_32, read big-endian
-```
-
-BLAKE2b with a 4-byte output length differs from the first 4 bytes of BLAKE2b-512, because the length is a parameter of the initial state. Both definitions follow `validate_equix_challenge` and `pack_equix_solution` in `hs_pow.c`.
-
-Counters are assigned in order and spent in order. A client that solves on several cores gives each core its own counter.
-
-A proof verifies only under the protocol letter and the session hash it was made for, so it fails on another protocol, another server, and another connection.
-
-## Commands
-
-The proof is an optional field of the commands that create resources.
-
-```
-smpNew = %s"NEW " rcvAuthKey rcvDhKey optBasicAuth subMode optQueueReqData optNtfCreds optProofOfWork
-smpLSet = %s"LSET " linkId queueLinkData optProofOfWork
-fnew = %s"FNEW " fileInfo rcvKeys optBasicAuth fileStorageTime optProofOfWork
-tnew = %s"TNEW " newNtfTkn optProofOfWork
-optProofOfWork = %s"0" / (%s"1" proofOfWork)
-```
-
-`LSET` is priced when the queue holds no link data; on a queue that holds some, it replaces the data and carries no proof. `NKEY`, `FADD` and `SNEW` are not priced. The first message to an unknown queue is out of scope.
-
-A batch of transmissions carries one proof per command. Creation commands are sent to the servers of the user over a direct session, so the proxy carries none of them.
-
-## Verification
-
-The server checks, in this order:
-
-1. `powEffort >= price of the tier of the session * units of the request` - integer comparison.
-2. `powEpoch` within the epoch window of the server, and at most one epoch ahead.
-3. `powCounter` is above the window of the session, or inside it and unused.
-4. `R * powEffort <= 2^32 - 1` - one Blake2b of 88 bytes.
-5. `equix_verify(challenge, S) == EQUIX_OK` - 50-120 microseconds.
-6. The counter is marked, and the resource is created.
-
-The counter is marked on every verified proof, including one whose command then fails, so a proof pays for one attempt.
-
-The window holds the last 64 counters, which admits proofs that arrive out of order, from commands sent concurrently on one session. A counter below the window is rejected, and the client that skipped ahead loses the proofs it left behind.
-
-Steps 1 to 3 cost less than a microsecond. Step 4 costs an attacker about `effort` Blake2b calls to pass with a random solution, so the Equi-X call in step 5 is what a forged proof buys. The server closes a session after 3 consecutive proofs that fail step 4 or step 5. An honest client checks its proof before sending it, so it never fails these steps; a stale proof or one below the price fails steps 1 to 3, which can happen to an honest client after a change of price or epoch, and closes nothing.
-
-## Entitlement
-
-SMP and NTF servers verify the entitlement proof in the handshake, as the XFTP server does. A name the server prices is verified once per session; a name it does not price is ignored without verification, and the session pays the default price. A proof that fails to verify leaves the session at the default price too.
-
-The tier of the session is fixed at the handshake, so every command in it is priced without further work.
-
-An entitlement lowers the price, and neither raises it nor removes it:
-
-```
-min(1, price) <= price_for_<name> <= price
-```
-
-The server exits at startup when a configured price breaks this rule, and logs each name that breaks it, as the XFTP server does when an entitlement storage time is below the default. An entitlement price equal to the default is allowed, as an equal storage time is on XFTP.
-
-The control port sets the three prices in one command, and refuses a triple that breaks the rule. The triple is checked as a whole, so the order in which prices change plays no part.
-
-This gives the badge a function on SMP and NTF, where it grants nothing today: the holder pays less CPU time, and a flood outside its tier leaves its price where it was.
-
-## Services
-
-A service session creates resources without a proof when the SMP server records its service as created before a configured date. `serviceCreatedAt` of the service record holds that date, so the services that presented certificates before the release are exempt, and the rule needs no migration.
-
-```
-[PROOF_OF_WORK]
-exempt_services_created_before = 2026-10-15
-```
-
-A service registered after that date pays the default price. Exempt sessions are a tier of their own in the statistics.
-
-The date is a transition. The follow-up work gives services a certificate signed by an operator, an online certificate under an offline one as SMP servers have, issued on a certificate request from each partner; a server recognises the operators in its configuration and exempts their services. It is out of scope here.
-
-## Clients of earlier versions
-
-A session below the version that introduces proof of work cannot present a proof. Its creation commands draw on one budget, shared by all such sessions: a number of creations per minute, set on the control port, unlimited at first.
-
-While an attacker uses a client of the proof-of-work version, the budget goes to clients of earlier versions and none of them notices it. When an attacker uses an earlier client, the damage is the budget. A budget of zero refuses them all; the generic lever against earlier versions stays the version range, set without a release.
-
-A command over the budget receives a new error, `BUSY`:
-
-```
-SMP:  ERR BUSY
-XFTP: FRErr BUSY
-NTF:  NRErr BUSY
-```
-
-The serializer sends `BUSY` to a session of the proof-of-work version as it is, and maps it for a session of an earlier version, as it maps `BLOCKED` for sessions below `clientNoticesSMPVersion` today:
-
-```
-SMP:  BUSY -> STORE busy
-NTF:  BUSY -> STORE busy
-XFTP: BUSY -> TIMEOUT
-```
-
-SMP and NTF share `ErrorType`, which has no `TIMEOUT`. Among the errors an SMP or NTF server sends, agents from simplexmq 7.0.0 retry only `STORE`; that release introduced SMP version 19 and ships in the apps from 7.0.0. An asynchronous `NEW` or `JOIN` of these agents retries with a growing interval and takes the next server of the user on each attempt, so a refused client moves to a server that has budget left. The XFTP agent retries `FNEW` on `TIMEOUT` from simplexmq 5.8.0. `TNEW` returns the error to the app that called `registerNtfToken`, and the agent holds no retry loop for it. An interactive command shows the error once, and the deployed apps show `STORE busy` in their generic error alert.
-
-Agents below SMP version 19 retry no error that a server sends. They end an asynchronous command on `STORE`, and the app of these versions shows the error without retrying the command, so a refused connection to a group member is lost.
-
-The other errors mislead or stop the client: `QUOTA` is shown as a connection that reached its limit of undelivered messages, `AUTH` as a connection error of authorisation, and in the deployed agents both end an asynchronous command. A budget of zero keeps the retries of clients from version 19 running at the longest interval, and a raised budget lets them through without an update.
-
-A client of the proof-of-work version shows `BUSY` to the user: an interactive command shows it at once, and a background command shows it when its retries expire on the client.
-
-## Learning the price
-
-The price reaches the client three ways, and each of them is a message the protocol already sends.
-
-1. The server handshake, at the start of the session. It states the price of every tier, because the entitlement proof arrives in the client handshake that follows.
-2. The response to a priced command. It states the price of the tier of the session, so a client that paid the old price learns the new one while its command succeeds.
-3. The error below, when the proof was absent, stale, or below the price. A client whose entitlement failed to verify learns here that it pays the default price.
-
-```
-powPrice = price serverEpoch  ; 8 bytes, appended to the response of a priced command
-```
-
-An increase costs one rejected command and the proof spent on it. A decrease costs nothing: the client over-pays until its next response, which states the lower price. A client that has been idle for longer than the epoch window solves at the last price it read, and pays one retry when the price moved meanwhile.
-
-The prices are public, as the suggested effort is in Tor, and the list of priced entitlement names is public with them.
-
-## Errors and retry
-
-A new error carries the price and the time of the server.
-
-```
-SMP:  ERR POW price epoch
-XFTP: FRErr (POW price epoch)
-NTF:  NRErr (POW price epoch)
-```
-
-The client resets its price and epoch from the error, solves at the stated price, and retries. Two retries are allowed for one command, which covers a price that moves again while the client solves; past that it reports that the server is busy, as it does when the effort exceeds its own maximum.
-
-A proof made for a higher effort than required is accepted, so a proof that outlives a decrease stays usable while its epoch holds.
-
-## Setting prices
-
-The operator sets the prices: the configuration holds the values the server starts with, and the control port reads and changes them while it runs.
-
-```
-[PROOF_OF_WORK]
-price = 16                  ; effort per unit without an entitlement, 0 = proof not required
-price_for_supporter = 4     ; effort per unit with the supporter entitlement, at least 1 and at most price
-price_for_legend = 2        ; effort per unit with the legend entitlement, at least 1 and at most price
-epoch_window_minutes = 5
-exempt_services_created_before = 2026-10-15
-```
-
-The keys follow `expire_files_hours_for_<name>` of the XFTP server, and on the XFTP server both keys name the same entitlements.
-
-Control port commands, on SMP, XFTP and NTF servers:
-
-```
-pow                    ; user role: prices, budget of earlier versions, epoch window, counts of the current period per tier
-pow p0 p1 p2           ; admin role: set the prices - p0 without an entitlement, p1 supporter, p2 legend
-pow old <n>            ; admin role: set the budget of earlier versions, creations per minute
-pow old unlimited      ; admin role: remove the budget
-```
-
-A change reaches new sessions through the handshake, and sessions in progress through their next response or error.
-
-Prices and the budget set on the control port are saved with the server state and restored at start, so a change made during an attack survives a restart that the attack outlasts. While they differ from the configuration, the server logs a warning at stop and at start, and `pow` shows both values.
-
-The XFTP and NTF control ports gain the admin role check that the SMP control port already has; both check the user role today.
-
-The estimator of Tor is deferred. If prices set by hand prove too slow, it runs per tier on the creations of that tier, between bounds set on the control port.
-
-## Statistics
-
-The server counts per tier, so a flood shows in its tier, and the use of each entitlement is accounted for. Sessions without an entitlement are counted under `default`, exempt services under `service`, and sessions of earlier versions under `old`.
-
-```
-sessions            ; sessions of the tier
-entFailed           ; entitlement proofs that failed to verify
-proofsAccepted
-effortAccepted      ; sum of the effort of accepted proofs
-proofsAbsent
-proofsBelowPrice
-proofsStale         ; epoch outside the window
-proofsReused        ; counter below the window or already marked
-proofsInvalid       ; Blake2b target or Equi-X check failed
-sessionsClosed      ; sessions closed after invalid proofs
-overBudget          ; creations of earlier versions refused by the budget
-created             ; queues, chunks or tokens created
-```
-
-The counts appear in `pow` for the current period, in the stats log, and in the Prometheus metrics. They name a tier, never a session.
-
-## Costs
-
-The rates below are estimates to be replaced by measurement on devices.
-
-A solver call hashes 2^16 indices. Compiled, a desktop core makes about 150 candidate solutions per second, measured by tevador. Interpreted at 1-2 microseconds per hash, a call spends about 100 milliseconds hashing, so the same core makes about 15-25, and a phone core, about three times slower, about 5-8.
-
-```
-effort   desktop, compiled   phone, interpreted
-     4              0.03 s                0.6 s
-    16              0.1 s                 2.5 s
-    64              0.4 s                10 s
-   256              1.7 s                40 s
-```
-
-A queue at a price of 4 costs a phone about 0.6 seconds, and a queue at 16 about 2.5 seconds. A 4 MB chunk stored for 48 hours is 128 units; at an XFTP price of 1 it costs a phone about 20 seconds, while the upload of the same chunk takes seconds to minutes. The prices of the configuration examples assume compiled solving, and fall with this table.
-
-The client maximum is one effort value: the largest that an iPhone 8 solves in 45-60 seconds and a current iPhone in 30 seconds. A benchmark on both devices sets it; by the table above it is about 200. A client reports a request priced above it as busy, so it bounds the prices an operator can set: the price of a queue, and the units of an XFTP chunk multiplied by the price per unit.
-
-Verification at 100 microseconds allows about 10000 proofs per second per core, which exceeds the rate at which queues are created and written to the store.
-
-## Attacker cost
-
-An attacker solves on desktops with the compiler, at 150 candidate solutions per second per core:
-
-```
-price    1 core      64 cores    1000 machines
-    4    37/s        2400/s      37000/s
-   16    9/s         600/s       9000/s
-  256    0.6/s       38/s        600/s
-```
-
-A desktop core of the attacker solves 20-30 times faster than a phone core of a user: three times from the hardware, and the rest from the compiler. The gap sets how high a price can rise before users feel it.
-
-The idle price is a speed bump. The defence is the increase in the tier the flood uses, and the statistics show which tier that is.
-
-An attacker without a badge floods the default tier. Its price rises, and badge holders keep their prices.
-
-An attacker who bought a badge presents it on every machine: at a price of 2, one badge on 1000 machines creates 75000 queues per second until the price of that tier is raised. The raise is paid by the holders of that badge while the flood lasts, and by no one else.
-
-The price of a badge tier rises at most to the default price. A flood in a badge tier that the default price does not hold back needs the default raised too, so users without a badge pay that raise as well; the other badge tiers keep their prices.
-
-## Client implementation
-
-The agent solves on demand, in one solver ordered by `NetworkRequestMode`: `NRMInteractive` work first, then `NRMBackground`. A solver call takes about 100 milliseconds on a phone, so background work yields between calls when interactive work arrives.
-
-Creation outside the actions of the user - connections to the members of a group - is background work, and background solving has a budget of CPU time per hour. Past it, background creations wait, and the asynchronous commands that carry them retry them later. A group of many members cannot turn the device into a miner.
-
-The solver keeps no stock. A proof is discarded when its epoch passes or its session ends.
-
-## Deployment
-
-Proof of work comes in the same version as the entitlement proof in the handshake: SMP version 23 and NTF version 4. XFTP carries the entitlement proof from version 4, which is released, so proof of work comes in XFTP version 5. Servers start with every price at zero, which asks for nothing, and operators raise them. The existing controls - `allowNewQueues`, `allowNewFiles`, the basic auth of the server - stay as they are.
-
-## Limits
-
- Proof of work prices bulk creation; it stops no one who is willing to pay. Tor states the same conclusion: the defence covers a single machine and a small botnet, and a large botnet needs another mechanism.
- Prices change by hand, so a flood runs at the old price until an operator raises it. The expiry bounds the stock prepared before the flood; the flood that follows is priced at the new value from the next response.
- Phones solve with the interpreter and attackers with the compiler, which gives an attacker 20-30 times a phone per core. Equi-X narrows the gap between a CPU and a GPU, which published measurements leave open; a hash-based puzzle would give one GPU a factor of about a thousand over a phone.
- Proofs are bound to a session, so a reconnection discards the unspent ones.
- The cost falls on the device of the user: battery and heat, most visible when a group of many members is created at once.
- Proof of work replaces no rate limit, and the servers limit neither creations nor commands per session today. A cap on creations per session is out of scope.
-
-## Open questions
-
-1. HashX against a fixed hash. Our clients interpret and an attacker compiles, which the estimates put at about 8 times on one core. A fixed hash - Equihash(60,3) over SipHash - removes that factor, and gives a GPU the same program for every challenge, so it runs thousands of instances in step, as the Equihash miners do; that factor is unmeasured. The measurements that decide it: interpreted solving on a mid-range Android phone and an iPhone, compiled against interpreted on one desktop core, and an estimate of a GPU solver for the fixed hash.
-2. The budget of background solving, in CPU seconds per hour.
-3. Sessions below SMP version 19: whether the budget of earlier versions applies to them, where a refusal ends their asynchronous creations, or they stay outside it and the version range is the lever against them.
-
-## Follow-up
-
-Certificates for services signed by an operator, with the requests of partners, as described under Services.
@@ -0,0 +1,9 @@
+#!/bin/sh
+set -eu
+
+version=$(awk '/^version:/ {print $2}' simplexmq.cabal)
+for dir in "$@"; do
+  if [ -d "$dir/build" ]; then
+    find "$dir/build" -mindepth 3 -maxdepth 3 -type d -name 'simplexmq-*' ! -name "simplexmq-$version" -exec rm -rf {} +
+  fi
+done
@@ -0,0 +1,27 @@
+#!/bin/sh
+set -eu
+
+command=$1
+hashes=$2
+
+sources() {
+  git ls-files -z '*.hs' '*.hsc'
+}
+
+case "$command" in
+  record)
+    sources | xargs -0 sha256sum > "$hashes"
+    ;;
+  restore)
+    sources | xargs -0 touch
+    while read -r hash file; do
+      if [ -f "$file" ] && [ "$(sha256sum "$file" | cut -d' ' -f1)" = "$hash" ]; then
+        touch -d 2000-01-01 "$file"
+      fi
+    done < "$hashes"
+    ;;
+  *)
+    echo "usage: $0 record|restore <hashes file>" >&2
+    exit 1
+    ;;
+esac
@@ -1,5 +1,8 @@
+# Copy to .env (next to docker-compose.yml) only to change a setting; without it
+# docker-compose.yml uses the values shown here.
+
 # ============================================================================
-# Required settings — the stack will not start without these.
+# Chain settings.
 # ============================================================================

 # Ethereum network: mainnet (the SNRC `.testing` contracts live on mainnet)
@@ -14,9 +17,16 @@ NETWORK=mainnet
 TRUSTED_NODE_URL=https://mainnet-checkpoint-sync.attestant.io

 # ============================================================================
-# Optional overrides — sensible defaults are baked into docker-compose.yml,
-# so leave these commented unless you need to change them.
+# Optional overrides — leave commented unless you need to change them.
 # ============================================================================

 # Nimbus NAT (default: any). For a stable public node set an explicit IP:
 #   NAT=extip:1.2.3.4        # your public IPv4: curl -s ifconfig.me
+
+# Resolver (defaults in the README's "Load and scaling" and "Logs" sections)
+#   SNRC_WORKERS=4                          # worker processes; default CPU count, at most 4
+#   SNRC_RPC_TIMEOUT=5                      # seconds per request to reth
+#   SNRC_LOG_FORMAT=json                    # default text (key=value)
+#   SNRC_LOG_COLOR=always                   # coloured `docker compose logs`
+#   SNRC_LOG_LEVEL=debug                    # also log health checks and idle connections
+#   SNRC_TRUSTED_PROXIES=172.16.0.0/12      # behind a reverse proxy on the host; see README
@@ -19,15 +19,15 @@ against **Ethereum mainnet** (where the `.testing` contracts live):

 ## 1. Configure

-Edit `.env` — the defaults work as-is; override only if needed:
+The defaults in `docker-compose.yml` work as-is:

 ```sh
 NETWORK=mainnet                                               # default
 TRUSTED_NODE_URL=https://mainnet-checkpoint-sync.attestant.io # default
 ```

-Everything else (NAT) has a working default baked into `docker-compose.yml`;
-uncomment the hints in `.env` only to override.
+To override these or NAT, copy `.env.example` to `.env` and edit it; `.env` is
+not committed.

 ## 2. Run

@@ -121,6 +121,15 @@ standalone for local dev (no Docker), via [`uv`](https://docs.astral.sh/uv/):
 uv run scripts/resolver/service/snrc-resolve.py  # defaults to local reth + mainnet .testing
 ```

+Tests and lint run from `scripts/resolver/service`:
+
+```sh
+uv run pytest
+uv run ruff check .
+```
+
+Dependencies are locked in `uv.lock`; the Docker image installs exactly those.
+
 Three routes, versioned separately from the protocol so each only changes when
 its own shape does:

@@ -243,7 +252,7 @@ wrong, `error` and `status` hold the same value, so one field is enough to read.

 `upstreamError` says only which exception type the RPC call raised. The text
 goes to the resolver's log instead, because `SNRC_RPC` can carry a provider key
-and urlopen puts the URL it failed on into the message. It is also the answer
+and the exception can carry the URL it failed on. It is also the answer
 when a registrar, controller or oracle address has no contract behind it: the
 empty reply is refused rather than read as zero, which would make every name
 look free.
@@ -374,3 +383,87 @@ here.
 To override any of them, set `SNRC_REGISTRY_<TLD>`, `SNRC_REGISTRAR_<TLD>` or
 `SNRC_CONTROLLER_<TLD>` on the `resolver` service in `docker-compose.yml`, or
 as env vars when you run the script directly.
+
+### Load and scaling
+
+A lookup reads the chain in at most three rounds: the name's status and
+registry entries, then its record from its resolver, then prices for a name
+that is free. The node runs the calls of a JSON-RPC batch one after another,
+so the contract reads of a round go to the chain as one `eth_call` to
+[Multicall3](https://github.com/mds1/multicall). A node that is slow for a
+moment therefore delays a lookup a few times, not once per read. Connections to
+the node are kept open and reused.
+
+The resolver answers HTTP/1.1, so each smp-server keeps its connections to it
+open instead of connecting for every lookup. An idle connection is closed after
+60 s; the smp-server drops its own idle ones after 30 s, so it closes them first.
+
+Each access log line ends with how long the request took, so slow requests
+show up in `docker compose logs resolver`.
+
+| Variable | Default | Meaning |
+|---|---|---|
+| `SNRC_WORKERS` | CPU count, at most 4 | processes sharing the port. If one exits, the others stop, so the container restarts |
+| `SNRC_RPC_TIMEOUT` | `5` | seconds to wait for each request to the node; the smp-server gives up after 3 |
+| `SNRC_MULTICALL` | `0xcA11bde05977b3631167028862bE2a173976CA11` | Multicall3 address. If it does not answer, each round is sent as a plain batch and the log says so once |
+
+### Logs
+
+Each event is one line: UTC time, level, event name, then `key=value` fields.
+
+```
+2026-09-26T08:06:19.992Z INFO  request  client=203.0.113.7 worker=12 method=GET path=/v2/resolve/[4fdd…].testing status=200 bytes=701 ms=35
+2026-09-26T08:06:20.051Z WARN  upstream_error  name=foobar.testing error=ConnectionRefusedError message="[Errno 111] Connection refused"
+```
+
+| Event | Level | Meaning |
+|---|---|---|
+| `listening` | info | started: address, workers, RPC endpoint, registries, trusted proxies |
+| `request` | info | one answered request; `/health` only at debug |
+| `upstream_error` | warn | a read from the node failed; the caller got 502 |
+| `multicall_unavailable` | warn | Multicall3 did not answer; rounds are sent as plain batches |
+| `client_gone` | warn | the caller hung up before the answer, usually an smp-server past its timeout |
+| `http_error` | warn | a malformed request; idle keep-alive timeouts only at debug |
+| `request_failed` | error | a request failed unexpectedly, with its traceback |
+| `worker_exited`, `worker_failed` | error | a worker stopped; the others stop too, so the container restarts |
+| `stopping` | info | stopped by a signal |
+
+| Variable | Default | Meaning |
+|---|---|---|
+| `SNRC_LOG_FORMAT` | `text` | `text` (`key=value`) or `json`, one object per line |
+| `SNRC_LOG_COLOR` | `auto` | `auto` colours only a terminal, `always`, `never`. Docker output is no terminal, so set `always` for coloured `docker compose logs` |
+| `SNRC_LOG_LEVEL` | `info` | `debug` also logs health checks and idle connections closing |
+| `SNRC_TRUSTED_PROXIES` | none | addresses or CIDRs of reverse proxies whose `X-Forwarded-For` names the client |
+
+With docker compose, set these, and those in "Load and scaling", in `.env`
+(`.env.example` lists them).
+
+Behind a reverse proxy such as Caddy on the host, the resolver sees the Docker
+network's gateway rather than the client. Trust that gateway, and the logged
+client is the last `X-Forwarded-For` address no trusted proxy added, so a caller
+through the proxy cannot claim another address. Everything else on the host that
+connects to `127.0.0.1:8000`, the smp-servers included, arrives through the same
+gateway and could set the logged address too; run the proxy in the compose network
+and trust only its address to avoid that.
+
+The gateway is
+`docker network inspect resolver_default --format '{{(index .IPAM.Config 0).Gateway}}'`,
+with the network named after the compose project. It changes when the network is
+recreated, as `docker compose down` does, so trust one of, in `.env`:
+
+- `SNRC_TRUSTED_PROXIES=172.16.0.0/12`: Docker's default pools for compose
+  networks, whatever subnet it picks. This also trusts every other container on the
+  host. Add the gateway too if Docker ever gives the network a `192.168.x.x` one.
+- a pinned subnet, so the gateway stays fixed, and only that gateway:
+
+  ```yaml
+  networks:
+    default:
+      ipam:
+        config:
+          - subnet: 172.30.0.0/24
+            gateway: 172.30.0.1
+  ```
+
+  in `docker-compose.yml`, with `SNRC_TRUSTED_PROXIES=172.30.0.1`, on a subnet no
+  other network on the host uses.
@@ -38,14 +38,14 @@ services:
      - sh
      - -c
      - |
-        if [ -d /home/user/nimbus-eth2/build/data/${NETWORK}/db ]; then
+        if [ -d /home/user/nimbus-eth2/build/data/${NETWORK:-mainnet}/db ]; then
          echo "Nimbus data dir already initialised — skipping checkpoint sync";
          exit 0;
        fi;
        /home/user/nimbus-eth2/build/nimbus_beacon_node trustedNodeSync \
-          --network=${NETWORK} \
-          --data-dir=/home/user/nimbus-eth2/build/data/${NETWORK} \
-          --trusted-node-url=${TRUSTED_NODE_URL} \
+          --network=${NETWORK:-mainnet} \
+          --data-dir=/home/user/nimbus-eth2/build/data/${NETWORK:-mainnet} \
+          --trusted-node-url=${TRUSTED_NODE_URL:-https://mainnet-checkpoint-sync.attestant.io} \
          --backfill=false
    restart: "no"

@@ -69,8 +69,8 @@ services:
          echo "Reth data already initialised — skipping snapshot download";
          exit 0;
        fi;
-        echo "Downloading Reth ${NETWORK} --minimal snapshot...";
-        reth download --datadir /data --chain ${NETWORK} --minimal && \
+        echo "Downloading Reth ${NETWORK:-mainnet} --minimal snapshot...";
+        reth download --datadir /data --chain ${NETWORK:-mainnet} --minimal && \
        touch /data/.snapshot-done && \
        echo "Snapshot download complete"
    restart: "no"
@@ -92,7 +92,7 @@ services:
    command: >
      node
      --datadir /data
-      --chain ${NETWORK}
+      --chain ${NETWORK:-mainnet}
      --minimal
      --authrpc.jwtsecret /jwt/jwt.hex
      --authrpc.addr 0.0.0.0 --authrpc.port 8551
@@ -117,8 +117,8 @@ services:
      - "9000:9000/udp"
      - "127.0.0.1:5052:5052"
    command: >
-      --network=${NETWORK}
-      --data-dir=/home/user/nimbus-eth2/build/data/${NETWORK}
+      --network=${NETWORK:-mainnet}
+      --data-dir=/home/user/nimbus-eth2/build/data/${NETWORK:-mainnet}
      --el=http://reth:8551
      --jwt-secret=/jwt/jwt.hex
      --non-interactive
@@ -131,6 +131,7 @@ services:
  # smp-server points its [NAMES] resolver_endpoint at this URL.
  # To change the host port, edit the LEFT side of the port mapping below.
  resolver:
+    image: snrc-resolve:local
    build:
      context: ./service
      dockerfile: Dockerfile
@@ -156,8 +157,18 @@ services:
      # SNRC_REGISTRAR_SIMPLEX: 0x...
      # SNRC_CONTROLLER_TESTING: 0x...
      # SNRC_CONTROLLER_SIMPLEX: 0x...
+      # Set in .env (see .env.example); unset or empty means the resolver's default.
+      SNRC_WORKERS: ${SNRC_WORKERS:-}
+      SNRC_RPC_TIMEOUT: ${SNRC_RPC_TIMEOUT:-}
+      SNRC_LOG_FORMAT: ${SNRC_LOG_FORMAT:-}
+      SNRC_LOG_COLOR: ${SNRC_LOG_COLOR:-}
+      SNRC_LOG_LEVEL: ${SNRC_LOG_LEVEL:-}
+      SNRC_TRUSTED_PROXIES: ${SNRC_TRUSTED_PROXIES:-}
    ports:
      - "127.0.0.1:8000:8000"
+    # a line per lookup; the local driver keeps 5 rotated files of 20 MB
+    logging:
+      driver: local
    restart: unless-stopped

 volumes:
@@ -0,0 +1,5 @@
+.venv
+**/__pycache__
+.pytest_cache
+.ruff_cache
+test_snrc_resolve.py
@@ -0,0 +1 @@
+3.13
@@ -1,9 +1,10 @@
 # syntax=docker/dockerfile:1.7
 # ---------- builder ----------
-# Use the official uv image (Astral) on top of a slim Python base.
-# uv resolves and installs the lockfile-free pyproject.toml in seconds and
-# produces a portable .venv we can copy into the runtime stage.
-FROM ghcr.io/astral-sh/uv:python3.13-bookworm-slim AS builder
+# The official uv image (Astral) on top of a slim Python base installs the
+# locked dependencies into a portable .venv for the runtime stage.
+# Pinned to the uv that wrote uv.lock (its bookworm images stopped at 0.9.30), on the
+# runtime's Debian release, so the .venv's Python path exists there.
+FROM ghcr.io/astral-sh/uv:0.12.16-python3.13-trixie-slim AS builder

 ENV UV_LINK_MODE=copy \
    UV_COMPILE_BYTECODE=1 \
@@ -12,17 +13,17 @@ ENV UV_LINK_MODE=copy \

 WORKDIR /app

-# Install deps first (separate layer) — script edits won't bust this cache.
-COPY pyproject.toml ./
+# Dependencies first (separate layer), exactly as locked: script edits don't bust this cache.
+COPY pyproject.toml uv.lock .python-version ./
 RUN --mount=type=cache,target=/root/.cache/uv \
-    uv sync --no-dev --no-install-project
+    uv sync --frozen --no-dev --no-install-project

 # Script is added after the dep layer for cache friendliness.
 COPY snrc-resolve.py ./

 # ---------- runtime ----------
 # Slim runtime — only the venv + script. No uv, no apt.
-FROM python:3.13-slim AS runtime
+FROM python:3.13-slim-trixie AS runtime

 ENV PYTHONUNBUFFERED=1 \
    PYTHONDONTWRITEBYTECODE=1 \
@@ -33,15 +34,15 @@ RUN groupadd --system --gid 10001 snrc && \
    useradd  --system --uid 10001 --gid snrc --no-create-home --shell /usr/sbin/nologin snrc

 WORKDIR /app
-COPY --from=builder --chown=snrc:snrc /app /app
+# owned by root, so the service cannot rewrite its own code
+COPY --from=builder /app /app

 USER snrc:snrc

 EXPOSE 8000

-# Liveness check hits the script's own /health route. ThreadingHTTPServer is
-# fast enough that 3s is generous for a localhost probe; restart if it stops
-# responding entirely.
+# Liveness check hits the script's own /health route. Three failures mark the
+# container unhealthy; compose does not restart it for that, but `docker ps` shows it.
 HEALTHCHECK --interval=30s --timeout=5s --start-period=10s --retries=3 \
    CMD ["python", "-c", "import urllib.request, sys; sys.exit(0 if urllib.request.urlopen('http://127.0.0.1:8000/health', timeout=3).status == 200 else 1)"]

@@ -9,5 +9,14 @@ dependencies = [
  "eth-hash[pycryptodome]>=0.7",
 ]

+[dependency-groups]
+dev = [
+  "pytest>=8",
+  "ruff>=0.6",
+]
+
 [tool.uv]
 package = false
+
+[tool.ruff.lint]
+select = ["E9", "F", "B"]
@@ -46,6 +46,15 @@ Environment:
                         (default: mainnet for .testing, empty for .simplex)
  SNRC_PORT              Listen port (default: 8000)
  SNRC_BIND              Bind address (default: 0.0.0.0)
+  SNRC_WORKERS           Worker processes sharing the port (default: CPU count, at most 4)
+  SNRC_RPC_TIMEOUT       Seconds to wait for each RPC request (default: 5)
+  SNRC_MULTICALL         Multicall3 contract that runs a round of reads as one call
+                         (default: 0xcA11bde05977b3631167028862bE2a173976CA11)
+  SNRC_LOG_FORMAT        text (key=value) or json (default: text)
+  SNRC_LOG_COLOR         auto (on a terminal), always or never (default: auto)
+  SNRC_LOG_LEVEL         debug, info, warning or error (default: info)
+  SNRC_TRUSTED_PROXIES   Comma-separated addresses or CIDRs of reverse proxies whose
+                         X-Forwarded-For names the client (default: none)

 Each TLD is a separate SNRC deployment with its own ENSRegistry; the
 resolver dispatches by the queried name's rightmost label.
@@ -64,19 +73,45 @@ Unrecognised payloads fall back to `0x`-prefixed raw hex.
 """

 import hashlib
+import ipaddress
 import json
+import logging
 import os
+import queue
+import signal
+import socket
 import sys
+import threading
 import time
+from contextlib import contextmanager
+from datetime import datetime, timezone
+from functools import lru_cache
+from http.client import BadStatusLine, HTTPConnection, HTTPSConnection
 from http.server import BaseHTTPRequestHandler, ThreadingHTTPServer
+from urllib.error import HTTPError
 from urllib.parse import unquote, urlparse
-from urllib.request import Request, urlopen

 from eth_hash.auto import keccak

 RPC = os.environ.get("SNRC_RPC", "http://127.0.0.1:8545")
 BIND = os.environ.get("SNRC_BIND", "0.0.0.0")
 PORT = int(os.environ.get("SNRC_PORT", "8000"))
+# The smp-server gives up after 3 s, so a slower call only holds a thread.
+RPC_TIMEOUT_S = float(os.environ.get("SNRC_RPC_TIMEOUT", "") or 5)
+# The node and the beacon client usually share the host, so not every core.
+MAX_DEFAULT_WORKERS = 4
+WORKERS = int(os.environ.get("SNRC_WORKERS", "") or min(MAX_DEFAULT_WORKERS, os.cpu_count() or 1))
+# Multicall3, at this address on mainnet and most chains. A node runs a JSON-RPC
+# batch one call after another, so a round of reads is sent as one eth_call.
+MULTICALL = os.environ.get("SNRC_MULTICALL", "") or "0xcA11bde05977b3631167028862bE2a173976CA11"
+LOG_FORMAT = os.environ.get("SNRC_LOG_FORMAT", "") or "text"
+LOG_COLOR = os.environ.get("SNRC_LOG_COLOR", "") or "auto"
+LOG_LEVEL = os.environ.get("SNRC_LOG_LEVEL", "") or "info"
+# Peers whose X-Forwarded-For is believed, such as the Docker gateway a reverse proxy on the host
+# connects through. Anyone else could put any address there.
+TRUSTED_PROXIES = tuple(
+    ipaddress.ip_network(p.strip(), strict=False) for p in os.environ.get("SNRC_TRUSTED_PROXIES", "").split(",") if p.strip()
+)

 # Each TLD is its own SNRC deployment with its own ENSRegistry. Dispatch
 # happens on the rightmost label of the queried name. Empty / unset means
@@ -121,34 +156,291 @@ COIN_ETH = 60
 COIN_BTC = 0
 COIN_XMR = 128
 COIN_DOT = 354
+RECORD_COINS = (COIN_ETH, COIN_BTC, COIN_XMR, COIN_DOT)

 ZERO_ADDR = "0x0000000000000000000000000000000000000000"

 # The registry prices in attoUSD (1e-18 USD); the protocol carries US cents.


+# ---------- Logging ----------
+
+LOGGER = logging.getLogger("snrc_resolve")
+LEVEL_NAMES = {logging.DEBUG: "DEBUG", logging.INFO: "INFO", logging.WARNING: "WARN", logging.ERROR: "ERROR"}
+# ANSI SGR codes
+DIM, BOLD, GREEN, YELLOW, RED = "2", "1", "32", "33", "31"
+LEVEL_COLORS = {"DEBUG": DIM, "INFO": GREEN, "WARN": YELLOW, "ERROR": RED}
+STATUS_COLORS = {2: GREEN, 3: GREEN, 4: YELLOW, 5: RED}
+
+
+def log_event(level: int, name: str, /, exc_info=None, **fields):
+    LOGGER.log(level, name, exc_info=exc_info, extra={"fields": fields})
+
+
+def _log_time(record: logging.LogRecord) -> str:
+    return datetime.fromtimestamp(record.created, timezone.utc).isoformat(timespec="milliseconds").replace("+00:00", "Z")
+
+
+def _log_value(value) -> str:
+    """A logfmt value: bare when it cannot be misread, JSON-quoted otherwise."""
+    if value is None:
+        return "-"
+    s = str(value)
+    if not s or any(c in s for c in ' ="\\') or not s.isprintable():
+        return json.dumps(s)
+    return s
+
+
+class TextFormatter(logging.Formatter):
+    def __init__(self, color: bool):
+        super().__init__()
+        self.color = color
+
+    def _paint(self, code: str, text: str) -> str:
+        return f"\033[{code}m{text}\033[0m" if self.color and code else text
+
+    def format(self, record: logging.LogRecord) -> str:
+        level = LEVEL_NAMES.get(record.levelno, record.levelname)
+        fields = " ".join(
+            self._paint(DIM, f"{k}=") + self._paint(STATUS_COLORS.get(v // 100, "") if k == "status" and isinstance(v, int) else "", _log_value(v))
+            for k, v in getattr(record, "fields", {}).items()
+        )
+        line = f"{self._paint(DIM, _log_time(record))} {self._paint(LEVEL_COLORS.get(level, ''), f'{level:<5}')} {self._paint(BOLD, record.getMessage())}"
+        if fields:
+            line += "  " + fields
+        if record.exc_info:
+            line += "\n" + self.formatException(record.exc_info)
+        return line
+
+
+class JsonFormatter(logging.Formatter):
+    def format(self, record: logging.LogRecord) -> str:
+        out = {
+            "time": _log_time(record),
+            "level": LEVEL_NAMES.get(record.levelno, record.levelname).lower(),
+            "event": record.getMessage(),
+            **getattr(record, "fields", {}),
+        }
+        if record.exc_info:
+            out["exception"] = self.formatException(record.exc_info)
+        return json.dumps(out, default=str)
+
+
+def setup_logging(stream=None):
+    """Sends the resolver's events to stderr in the configured format."""
+    stream = stream or sys.stderr
+    if LOG_FORMAT not in ("text", "json"):
+        raise ValueError(f"SNRC_LOG_FORMAT must be text or json, not {LOG_FORMAT!r}")
+    if LOG_COLOR not in ("auto", "always", "never"):
+        raise ValueError(f"SNRC_LOG_COLOR must be auto, always or never, not {LOG_COLOR!r}")
+    level = logging.getLevelName(LOG_LEVEL.upper())
+    if not isinstance(level, int):
+        raise ValueError(f"SNRC_LOG_LEVEL must be debug, info, warning or error, not {LOG_LEVEL!r}")
+    color = LOG_COLOR == "always" or (LOG_COLOR == "auto" and stream.isatty())
+    handler = logging.StreamHandler(stream)
+    handler.setFormatter(JsonFormatter() if LOG_FORMAT == "json" else TextFormatter(color))
+    LOGGER.handlers[:] = [handler]
+    LOGGER.setLevel(level)
+    LOGGER.propagate = False
+
+
 # ---------- RPC + ABI helpers (mirrors ens-lookup.py shape) ----------

+RPC_URL = urlparse(RPC)
+# Set a non-default User-Agent; Cloudflare-fronted public RPCs (drpc,
+# publicnode, etc.) reject `Python-urllib/3.x` with 403.
+RPC_HEADERS = {"Content-Type": "application/json", "User-Agent": "snrc-resolve/1.0"}
+
+# Idle keep-alive connections to SNRC_RPC. A connection per call costs most of
+# a lookup's CPU and leaves a TIME_WAIT socket per call, which exhausts local
+# ports at a few dozen lookups per second.
+# Idle connections kept per worker; more are closed after use. 4 workers stay well
+# under reth's default limit of 500 connections.
+RPC_POOL_SIZE = 32
+_rpc_pool = queue.LifoQueue(maxsize=RPC_POOL_SIZE)
+
+
+def _new_rpc_connection():
+    conn_class = HTTPSConnection if RPC_URL.scheme == "https" else HTTPConnection
+    return conn_class(RPC_URL.hostname, RPC_URL.port, timeout=RPC_TIMEOUT_S)
+
+
+def _post_rpc(conn, body: bytes) -> bytes:
+    path = (RPC_URL.path or "/") + (f"?{RPC_URL.query}" if RPC_URL.query else "")
+    conn.request("POST", path, body, RPC_HEADERS)
+    res = conn.getresponse()
+    data = res.read()
+    # HTTPError, as urlopen raised: RuntimeError means the call itself failed
+    if not 200 <= res.status < 300:
+        raise HTTPError(RPC, res.status, res.reason, res.headers, None)
+    return data
+
+
+def _post_pooled(conn, body: bytes) -> bytes:
+    try:
+        data = _post_rpc(conn, body)
+    except BaseException:
+        conn.close()
+        raise
+    try:
+        _rpc_pool.put_nowait(conn)
+    except queue.Full:
+        conn.close()
+    return data
+
+
+def _send_rpc(payload) -> object:
+    body = json.dumps(payload).encode()
+    try:
+        idle = _rpc_pool.get_nowait()
+    except queue.Empty:
+        return json.loads(_post_pooled(_new_rpc_connection(), body))
+    try:
+        return json.loads(_post_pooled(idle, body))
+    except (ConnectionError, BadStatusLine):
+        # the node closed the idle connection; every call is a read, so resending is safe
+        return json.loads(_post_pooled(_new_rpc_connection(), body))
+
+
+# Reads prefetched for the request being answered, keyed by _read_key. Only set
+# inside request_reads(), so code called outside a request reads one call at a time.
+_request = threading.local()
+_UNREAD = object()
+
+
+def _read_key(method, params) -> str:
+    return method + json.dumps(params, sort_keys=True)
+
+
+@contextmanager
+def request_reads():
+    _request.reads = {}
+    try:
+        yield
+    finally:
+        del _request.reads
+
+
 def rpc(method, params):
-    body = json.dumps(
-        {"jsonrpc": "2.0", "method": method, "params": params, "id": 1}
-    ).encode()
-    # Set a non-default User-Agent; Cloudflare-fronted public RPCs (drpc,
-    # publicnode, etc.) reject `Python-urllib/3.x` with 403.
-    req = Request(
-        RPC,
-        data=body,
-        headers={
-            "Content-Type": "application/json",
-            "User-Agent": "snrc-resolve/1.0",
-        },
-    )
-    res = json.loads(urlopen(req, timeout=15).read())
+    reads = getattr(_request, "reads", None)
+    if reads is not None:
+        read = reads.get(_read_key(method, params), _UNREAD)
+        if isinstance(read, RuntimeError):
+            raise read
+        if read is not _UNREAD:
+            return read
+    res = _send_rpc({"jsonrpc": "2.0", "method": method, "params": params, "id": 1})
    if "error" in res:
        raise RuntimeError(res["error"])
    return res["result"]


+def _send_batch(requests):
+    """Answers of a JSON-RPC batch in request order, None for a request left
+    unanswered; all None when the node does not batch."""
+    res = _send_rpc([{"jsonrpc": "2.0", "id": i, "method": m, "params": p} for i, (m, p) in enumerate(requests)])
+    # a node that does not batch answers with a single error object
+    by_id = {r.get("id"): r for r in res if isinstance(r, dict)} if isinstance(res, list) else {}
+    return [by_id.get(i) for i in range(len(requests))]
+
+
+def _is_latest_call(method, params) -> bool:
+    return method == "eth_call" and params[1] == "latest"
+
+
+_multicall_failed_logged = False
+
+
+def _remember(reads, requests, answers):
+    for (m, p), r in zip(requests, answers, strict=True):
+        if r is not None and ("result" in r or "error" in r):
+            reads[_read_key(m, p)] = RuntimeError(r["error"]) if "error" in r else r["result"]
+
+
+def prefetch(requests):
+    """Sends reads the request will make in one round trip, with its contract
+    reads as one multicall. A read left unanswered is made on its own when the
+    code gets to it."""
+    global _multicall_failed_logged
+    reads = getattr(_request, "reads", None)
+    if reads is None:
+        return
+    todo = [(m, p) for m, p in requests if _read_key(m, p) not in reads]
+    if len(todo) < 2:
+        return
+    calls = [(m, p) for m, p in todo if _is_latest_call(m, p)]
+    if len(calls) < 2:
+        _remember(reads, todo, _send_batch(todo))
+        return
+    others = [(m, p) for m, p in todo if not _is_latest_call(m, p)]
+    multicall = eth_call_read(MULTICALL, encode_aggregate3([(p[0]["to"], p[0]["data"]) for _, p in calls]))
+    answers = _send_batch(others + [multicall])
+    if all(r is None for r in answers):
+        return
+    _remember(reads, others, answers[:-1])
+    try:
+        result = (answers[-1] or {}).get("result")
+        if not isinstance(result, str):
+            raise ValueError(f"multicall answered {answers[-1]!r}")
+        results = decode_aggregate3(result)
+        if len(results) != len(calls):
+            raise ValueError("multicall answered a different number of calls")
+    except (KeyError, TypeError, ValueError) as e:
+        if not _multicall_failed_logged:
+            _multicall_failed_logged = True
+            log_event(logging.WARNING, "multicall_unavailable", multicall=MULTICALL, error=repr(e), fallback="batch")
+        _remember(reads, calls, _send_batch(calls))
+        return
+    for (m, p), (success, data) in zip(calls, results, strict=True):
+        reads[_read_key(m, p)] = "0x" + data.hex() if success else RuntimeError("execution reverted")
+
+
+AGGREGATE3 = "0x82ad56cb"  # aggregate3((address,bool,bytes)[])
+
+
+def encode_aggregate3(calls) -> str:
+    """Calldata for Multicall3.aggregate3 with every call allowed to fail."""
+    tuples = []
+    for to, data in calls:
+        b = bytes.fromhex(data[2:])
+        tuples.append(
+            int(to, 16).to_bytes(32, "big")
+            + (1).to_bytes(32, "big")
+            + (0x60).to_bytes(32, "big")
+            + len(b).to_bytes(32, "big")
+            + b
+            + b"\x00" * ((-len(b)) % 32)
+        )
+    offsets, at = [], 32 * len(tuples)
+    for t in tuples:
+        offsets.append(at.to_bytes(32, "big"))
+        at += len(t)
+    body = (0x20).to_bytes(32, "big") + len(tuples).to_bytes(32, "big") + b"".join(offsets) + b"".join(tuples)
+    return AGGREGATE3 + body.hex()
+
+
+def decode_aggregate3(hex_data: str):
+    """Multicall3.aggregate3's (bool success, bytes returnData)[]."""
+    raw = bytes.fromhex(hex_data[2:] if hex_data.startswith("0x") else hex_data)
+
+    def word(at: int) -> int:
+        if at + 32 > len(raw):
+            raise ValueError("multicall answer is truncated")
+        return int.from_bytes(raw[at:at + 32], "big")
+
+    array = word(0)
+    base = array + 32
+    out = []
+    for i in range(word(array)):
+        item = base + word(base + 32 * i)
+        data = item + word(item + 32)
+        length = word(data)
+        if data + 32 + length > len(raw):
+            raise ValueError("multicall answer is truncated")
+        out.append((word(item) != 0, raw[data + 32:data + 32 + length]))
+    return out
+
+
 def namehash(name: str) -> bytes:
    node = b"\x00" * 32
    if name:
@@ -184,11 +476,14 @@ def node_of(name: str) -> bytes:
 # ---------- Registration status ----------


+BLOCK_READ = ("eth_getBlockByNumber", ["latest", False])
+
+
 def head_block():
    """How far behind the node is. Unlike expiry, this is the one thing that has
    to be measured against the host clock: a node that stops still has a block."""
    try:
-        block = rpc("eth_getBlockByNumber", ["latest", False])
+        block = rpc(*BLOCK_READ)
        return {
            "blockNumber": decode_uint(block["number"]),
            "chainLagSeconds": int(time.time()) - decode_uint(block["timestamp"]),
@@ -199,13 +494,13 @@ def head_block():

 def chain_now() -> int:
    """Expiry is compared against the block timestamp, never the host clock."""
-    block = rpc("eth_getBlockByNumber", ["latest", False])
+    block = rpc(*BLOCK_READ)
    return decode_uint(block["timestamp"])


 def grace_period(registrar: str) -> int:
    """A deployment can configure a different window, so it is read on chain."""
-    return decode_uint(eth_call(registrar, selector("GRACE_PERIOD()")))
+    return decode_uint(eth_call(*grace_call(registrar)))


 def expiry_status(expires: int, grace: int, now: int) -> str:
@@ -225,8 +520,7 @@ def reservation_reason(tld: str, token: int) -> int:
    controller = CONTROLLERS.get(tld)
    if not controller:
        return 0
-    raw = eth_call(controller, selector("reservedNames(bytes32)") + encode_uint(token))
-    return decode_uint(raw)
+    return decode_uint(eth_call(*reserved_call(controller, token)))


 def pricing_params(tld: str):
@@ -235,7 +529,8 @@ def pricing_params(tld: str):
    controller = CONTROLLERS.get(tld)
    if not controller:
        return None
-    oracle = decode_address(eth_call(controller, selector("prices()")))
+    prefetch([eth_call_read(*prices_call(controller)), eth_call_read(*min_length_call(controller))])
+    oracle = decode_address(eth_call(*prices_call(controller)))
    if oracle == ZERO_ADDR:
        return None
    try:
@@ -247,6 +542,8 @@ def pricing_params(tld: str):


 SECONDS_PER_YEAR = 31536000
+# an ENS-shaped oracle prices names by length up to six letters
+LETTER_TIERS = range(1, 7)
 ATTO_PER_CENT = 10**16


@@ -255,13 +552,15 @@ def read_oracle_prices(controller: str, oracle: str):
    protocol carries. An ENS-shaped oracle prices in attoUSD per second and
    charges a premium on lapsed names that it does not expose, so a quote from
    it is only safe for a name that was never registered."""
+    # either oracle shape is answered in the same round trip
+    prefetch([eth_call_read(*prices_call(oracle))] + [eth_call_read(*letter_price_call(oracle, n)) for n in LETTER_TIERS])
    try:
-        base, tiers = decode_prices(eth_call(oracle, selector("prices()")))
+        base, tiers = decode_prices(eth_call(*prices_call(oracle)))
        premium_unknown = False
    except RuntimeError:
        base, tiers = decode_letter_prices(oracle)
        premium_unknown = True
-    min_len = decode_uint(eth_call(controller, selector("minCharLength()")))
+    min_len = decode_uint(eth_call(*min_length_call(controller)))
    return {
        # lengths the registry refuses are left out rather than priced at zero
        "registrationPrices": {n: c for n, c in tiers.items() if n >= min_len},
@@ -277,9 +576,9 @@ def decode_letter_prices(oracle: str):
    the six-letter tier stops at five, and charges its highest tier for anything
    longer, which is what basePrice means here."""
    tiers = {}
-    for n in range(1, 7):
+    for n in LETTER_TIERS:
        try:
-            rate = decode_uint(eth_call(oracle, selector(f"price{n}Letter()")))
+            rate = decode_uint(eth_call(*letter_price_call(oracle, n)))
        except RuntimeError:
            if n <= 5:
                raise
@@ -301,6 +600,9 @@ def decode_prices(hex_data: str):
    base = int.from_bytes(raw[:32], "big")
    at = int.from_bytes(raw[32:64], "big")
    count = int.from_bytes(raw[at:at + 32], "big")
+    # the count comes from the answer, so it is checked against the answer's length
+    if at + 32 + count * 64 > len(raw):
+        raise RuntimeError("prices(): short response")
    tiers = {}
    for i in range(count):
        item = at + 32 + i * 64
@@ -328,9 +630,7 @@ def name_status(name: str):
    # The 2LD's label is that key at any depth. node_of decodes a bracket only
    # in a two-label name, so a bracket subname gets a status but no record.
    token = label_token(labels[-2])
-    expires = decode_uint(
-        eth_call(registrar, selector("nameExpires(uint256)") + encode_uint(token))
-    )
+    expires = decode_uint(eth_call(*expires_call(registrar, token)))
    grace = grace_period(registrar) if expires else 0
    now = chain_now()
    status = expiry_status(expires, grace, now)
@@ -358,12 +658,17 @@ def name_status(name: str):
    return out


+@lru_cache(maxsize=None)
 def selector(signature: str) -> str:
    return "0x" + keccak(signature.encode())[:4].hex()


+def eth_call_read(to: str, data: str):
+    return "eth_call", [{"to": to, "data": data}, "latest"]
+
+
 def eth_call(to: str, data: str) -> str:
-    result = rpc("eth_call", [{"to": to, "data": data}, "latest"])
+    result = rpc(*eth_call_read(to, data))
    if result == "0x":
        raise RuntimeError(f"empty return from {to}: no contract at that address?")
    return result
@@ -385,7 +690,7 @@ def registered_label(registrar: str, token: int):
    """The plaintext label the registrar recorded at registration, keyed by the
    hash of that label. None when the name was registered without
    registerWithLabel, so the registrar cannot name it."""
-    raw = decode_bytes(eth_call(registrar, selector("labelOf(uint256)") + encode_uint(token)))
+    raw = decode_bytes(eth_call(*label_call(registrar, token)))
    return raw.decode("utf-8", errors="replace") if raw else None


@@ -427,7 +732,7 @@ def encode_text_call(node: bytes, key: str) -> str:


 def text(resolver: str, node: bytes, key: str) -> str:
-    raw = decode_bytes(eth_call(resolver, encode_text_call(node, key)))
+    raw = decode_bytes(eth_call(*text_call(resolver, node, key)))
    return raw.decode("utf-8", errors="replace") if raw else ""


@@ -446,7 +751,7 @@ def addr_multicoin(resolver: str, node: bytes, coin_type: int):
    payload doesn't match any recognised on-chain shape. Returns None when
    the record is unset."""
    try:
-        raw = decode_bytes(eth_call(resolver, encode_addr_multicoin_call(node, coin_type)))
+        raw = decode_bytes(eth_call(*addr_call(resolver, node, coin_type)))
    except RuntimeError:
        return None
    if not raw:
@@ -465,6 +770,81 @@ def addr_multicoin(resolver: str, node: bytes, coin_type: int):
        return "0x" + raw.hex()


+# ---------- Contract calls, as (to, data) ----------
+# Shared by the reads and prefetch, so a prefetched read is found by the code that makes it.
+
+
+def expires_call(registrar: str, token: int):
+    return registrar, selector("nameExpires(uint256)") + encode_uint(token)
+
+
+def grace_call(registrar: str):
+    return registrar, selector("GRACE_PERIOD()")
+
+
+def label_call(registrar: str, token: int):
+    return registrar, selector("labelOf(uint256)") + encode_uint(token)
+
+
+def reserved_call(controller: str, token: int):
+    return controller, selector("reservedNames(bytes32)") + encode_uint(token)
+
+
+def prices_call(contract: str):
+    return contract, selector("prices()")
+
+
+def letter_price_call(oracle: str, letters: int):
+    return oracle, selector(f"price{letters}Letter()")
+
+
+def min_length_call(controller: str):
+    return controller, selector("minCharLength()")
+
+
+def resolver_call(registry: str, node: bytes):
+    return registry, selector("resolver(bytes32)") + node.hex()
+
+
+def owner_call(registry: str, node: bytes):
+    return registry, selector("owner(bytes32)") + node.hex()
+
+
+def text_call(resolver: str, node: bytes, key: str):
+    return resolver, encode_text_call(node, key)
+
+
+def addr_call(resolver: str, node: bytes, coin_type: int):
+    return resolver, encode_addr_multicoin_call(node, coin_type)
+
+
+def lookup_reads(name: str):
+    """The reads a lookup makes before it knows the name's resolver."""
+    labels = name.split(".")
+    tld = labels[-1]
+    reads = []
+    registrar = REGISTRARS.get(tld)
+    if registrar and len(labels) >= 2:
+        token = label_token(labels[-2])
+        reads += [BLOCK_READ, eth_call_read(*expires_call(registrar, token)), eth_call_read(*grace_call(registrar))]
+        if len(labels) == 2 and is_encoded_labelhash(labels[0]):
+            reads.append(eth_call_read(*label_call(registrar, token)))
+        if CONTROLLERS.get(tld):
+            reads.append(eth_call_read(*reserved_call(CONTROLLERS[tld], token)))
+    registry = REGISTRIES.get(tld)
+    if registry:
+        node = node_of(name)
+        reads += [eth_call_read(*resolver_call(registry, node)), eth_call_read(*owner_call(registry, node))]
+    return reads
+
+
+def record_reads(resolver: str, node: bytes):
+    """The reads of a name's record from its resolver."""
+    return [eth_call_read(*text_call(resolver, node, k)) for k in TEXT_KEYS] + [
+        eth_call_read(*addr_call(resolver, node, coin)) for coin in RECORD_COINS
+    ]
+
+
 # ---------- Coin-specific address encoders ----------
 # Each takes raw bytes as stored under ENSIP-9 and returns the canonical
 # user-facing string for that chain (EIP-55 for ETH, bech32/base58check
@@ -665,9 +1045,9 @@ def split_links(value: str) -> list:


 def upstream_error(subject: dict, e: Exception) -> dict:
-    """urlopen puts the failing URL into its message and SNRC_RPC can carry a
-    provider key, so the text goes to the log and only the type to the caller."""
-    print(f"upstream error: {type(e).__name__}: {e}", file=sys.stderr)
+    """The exception can carry the failing URL and SNRC_RPC can carry a provider
+    key, so the text goes to the log and only the type to the caller."""
+    log_event(logging.WARNING, "upstream_error", **subject, error=type(e).__name__, message=str(e))
    return {
        **subject,
        "error": "upstreamError",
@@ -680,9 +1060,8 @@ def name_record(name: str):
    has one, with every field unset."""
    registry = REGISTRIES[name.rsplit(".", 1)[-1]]
    node = node_of(name)
-    node_hex = node.hex()
-    resolver_addr = decode_address(eth_call(registry, selector("resolver(bytes32)") + node_hex))
-    owner = decode_address(eth_call(registry, selector("owner(bytes32)") + node_hex))
+    resolver_addr = decode_address(eth_call(*resolver_call(registry, node)))
+    owner = decode_address(eth_call(*owner_call(registry, node)))
    rec = {
        "name": canonical_name(name),
        "nickname": "",
@@ -699,6 +1078,7 @@ def name_record(name: str):
    }
    if resolver_addr == ZERO_ADDR:
        return rec
+    prefetch(record_reads(resolver_addr, node))
    texts = {}
    for k in TEXT_KEYS:
        try:
@@ -734,6 +1114,7 @@ def registration(name: str):
    tld = name.rsplit(".", 1)[-1]
    if not REGISTRIES.get(tld):
        return 400, {"name": name, "error": "tldNotConfigured"}
+    prefetch(lookup_reads(name))
    reg = name_status(name)
    status = reg["status"]
    if status in ("registered", "grace"):
@@ -788,7 +1169,7 @@ def resolve(name: str):
        }

    node = node_of(name)
-    node_hex = node.hex()
+    prefetch(lookup_reads(name))

    # Before the resolver lookup, so a lapsed name is not reported as noResolver.
    reg = name_status(name)
@@ -806,13 +1187,12 @@ def resolve(name: str):
        }
        return (404 if reg["status"] == "unregistered" else 410), body

-    resolver_raw = eth_call(registry, selector("resolver(bytes32)") + node_hex)
-    resolver_addr = decode_address(resolver_raw)
+    resolver_addr = decode_address(eth_call(*resolver_call(registry, node)))
    if resolver_addr == ZERO_ADDR:
        # A registered name always resolves: with no resolver set the record is
        # still returned with every field unset, so "taken until <date>" stays
        # answerable. For a subname, no owner means nobody created it.
-        owner = decode_address(eth_call(registry, selector("owner(bytes32)") + node_hex))
+        owner = decode_address(eth_call(*owner_call(registry, node)))
        if len(name.split(".")) > 2 and owner == ZERO_ADDR:
            return 404, {
                "name": name,
@@ -837,9 +1217,9 @@ def resolve(name: str):
            **reg,
        }

-    owner_raw = eth_call(registry, selector("owner(bytes32)") + node_hex)
-    owner = decode_address(owner_raw)
+    owner = decode_address(eth_call(*owner_call(registry, node)))

+    prefetch(record_reads(resolver_addr, node))
    texts = {}
    for k in TEXT_KEYS:
        try:
@@ -878,12 +1258,34 @@ def resolve(name: str):
 # ---------- HTTP layer ----------

 class Handler(BaseHTTPRequestHandler):
+    # the smp-server reuses a connection only after an HTTP/1.1 response
+    protocol_version = "HTTP/1.1"
+    # idle seconds before a kept-alive connection is closed; the smp-server closes
+    # its idle ones after 30-35 s, so it is the one to close them
+    timeout = 60
+
+    def setup(self):
+        super().setup()
+        # headers and body go out in separate writes, which Nagle holds for the client's delayed ACK
+        self.request.setsockopt(socket.IPPROTO_TCP, socket.TCP_NODELAY, 1)
+
+    def handle_one_request(self):
+        # on a kept-alive connection these still hold the previous request's values
+        self._started = self._sent = self.path = self.headers = None
+        super().handle_one_request()
+
    def do_GET(self):  # noqa: N802 - http.server contract
+        self._started = time.monotonic()
+        if self._has_body():
+            # an unread body would be taken for the next request on this connection, which a
+            # reverse proxy reusing it would pass to another client (request smuggling)
+            self._respond(400, {"error": "unexpectedBody"}, close=True)
+            return
        path = urlparse(self.path).path
        parts = [unquote(p) for p in path.split("/") if p]

        if parts == ["health"]:
-            self._respond(200, {"ok": True, "rpc": RPC, "registries": REGISTRIES, **head_block()})
+            self._respond(200, {"ok": True, "rpc": public_endpoint(RPC), "registries": REGISTRIES, **head_block()})
            return

        if len(parts) == 3 and parts[0] == "v2" and parts[1] == "resolve":
@@ -892,7 +1294,8 @@ class Handler(BaseHTTPRequestHandler):
                self._respond(400, {"name": name, "error": "notFullyQualified"})
                return
            try:
-                status, body = registration(name)
+                with request_reads():
+                    status, body = registration(name)
            except Exception as e:  # surface upstream errors as 502
                status, body = 502, upstream_error({"name": name}, e)
            self._respond(status, body)
@@ -915,7 +1318,8 @@ class Handler(BaseHTTPRequestHandler):
                )
                return
            try:
-                status, body = resolve(name)
+                with request_reads():
+                    status, body = resolve(name)
            except Exception as e:  # surface upstream errors as 502
                status, body = 502, upstream_error({"name": name}, e)
            self._respond(status, body)
@@ -930,34 +1334,176 @@ class Handler(BaseHTTPRequestHandler):
            },
        )

-    def _respond(self, status: int, body: dict):
+    def _has_body(self) -> bool:
+        # a malformed header line ends parsing, leaving the rest, Content-Length included, as payload
+        if self.headers.defects or self.headers.get_payload():
+            return True
+        if self.headers.get_all("Transfer-Encoding"):
+            return True
+        return any(length.strip() != "0" for length in self.headers.get_all("Content-Length") or [])
+
+    def _respond(self, status: int, body: dict, close: bool = False):
        data = json.dumps(body, indent=2).encode()
+        # send_response logs the request, so the size is known before it
+        self._sent = len(data)
        self.send_response(status)
        self.send_header("Content-Type", "application/json")
        self.send_header("Content-Length", str(len(data)))
+        if close:
+            # also sets close_connection, so the server closes it after this response
+            self.send_header("Connection", "close")
        self.end_headers()
        self.wfile.write(data)

+    def address_string(self) -> str:
+        forwarded = self.headers.get_all("X-Forwarded-For") if self.headers else None
+        return client_address(self.client_address[0], ",".join(forwarded) if forwarded else None)
+
+    def log_request(self, code="-", size="-"):
+        started = self._started
+        path = urlparse(self.path).path if self.path else None
+        log_event(
+            # the container's health check runs every 30 s
+            logging.DEBUG if path == "/health" else logging.INFO,
+            "request",
+            client=self.address_string(),
+            worker=os.getpid(),
+            method=getattr(self, "command", None),
+            path=unquote(self.path) if self.path else None,
+            status=getattr(code, "value", code),
+            bytes=self._sent,
+            ms=round((time.monotonic() - started) * 1000) if started else None,
+        )
+
+    def log_error(self, fmt, *args):
+        message = fmt % args
+        # a kept-alive connection left idle is closed on purpose
+        level = logging.DEBUG if message.startswith("Request timed out") else logging.WARNING
+        log_event(level, "http_error", client=self.address_string(), worker=os.getpid(), message=message)
+
    def log_message(self, fmt, *args):
-        # Quiet the default per-request access log; route to stderr in one line.
-        sys.stderr.write(f"{self.address_string()} - {fmt % args}\n")
+        log_event(logging.INFO, "http", client=self.address_string(), message=fmt % args)
+
+
+class ResolverServer(ThreadingHTTPServer):
+    # socketserver's default of 5 drops simultaneous connections, each retried by
+    # TCP after 1 s, and the smp-server gives up after 3 s. The kernel caps it at somaxconn.
+    request_queue_size = 128
+
+    def handle_error(self, request, client_address):
+        error = sys.exc_info()[1]
+        if isinstance(error, ConnectionError):
+            # the smp-server hung up, usually after its own timeout
+            log_event(logging.WARNING, "client_gone", client=client_address[0], worker=os.getpid(), error=type(error).__name__)
+        else:
+            log_event(logging.ERROR, "request_failed", client=client_address[0], worker=os.getpid(), exc_info=True)
+
+
+def public_endpoint(url: str) -> str:
+    """The RPC endpoint without credentials, path or query, where a provider key would be."""
+    parsed = urlparse(url)
+    return f"{parsed.scheme}://{parsed.netloc.rpartition('@')[2]}"
+
+
+def client_address(peer: str, forwarded_for: str | None) -> str:
+    """The peer, or behind trusted proxies the last X-Forwarded-For address none of them added."""
+    if not forwarded_for or not _trusted(peer):
+        return peer
+    hops = [hop.strip() for hop in forwarded_for.split(",")]
+    for hop in reversed(hops):
+        # an address it cannot read, and anything claimed before it, is not believed
+        if _address(hop) is None:
+            return peer
+        if not _trusted(hop):
+            return hop
+    return hops[0]
+
+
+def _address(text: str):
+    try:
+        ip = ipaddress.ip_address(text)
+    except ValueError:
+        return None
+    return ip.ipv4_mapped or ip if ip.version == 6 else ip
+
+
+def _trusted(text: str) -> bool:
+    ip = _address(text)
+    return ip is not None and any(ip in net for net in TRUSTED_PROXIES)
+
+
+def serve(reuse_port: bool):
+    server = ResolverServer((BIND, PORT), Handler, bind_and_activate=False)
+    server.allow_reuse_port = reuse_port
+    try:
+        server.server_bind()
+        server.server_activate()
+        server.serve_forever()
+    finally:
+        server.server_close()
+
+
+def stop_on(signum, _frame):
+    log_event(logging.INFO, "stopping", signal=signal.Signals(signum).name)
+    sys.exit(0)
+
+
+def supervise(workers: int):
+    """Runs the workers, each with its own socket on the shared port. One worker
+    exiting stops the others, so the container restarts instead of running short."""
+    children = []
+
+    def stop(*_):
+        for pid in children:
+            try:
+                os.kill(pid, signal.SIGTERM)
+            except ProcessLookupError:
+                pass
+
+    def stop_and_exit(signum, frame):
+        stop()
+        stop_on(signum, frame)
+
+    # before forking, so a signal during startup cannot orphan the workers
+    signal.signal(signal.SIGTERM, stop_and_exit)
+    signal.signal(signal.SIGINT, stop_and_exit)
+    for _ in range(workers):
+        pid = os.fork()
+        if pid == 0:
+            signal.signal(signal.SIGTERM, signal.SIG_DFL)
+            signal.signal(signal.SIGINT, signal.SIG_DFL)
+            code = 0
+            try:
+                serve(reuse_port=True)
+            except BaseException:
+                log_event(logging.ERROR, "worker_failed", worker=os.getpid(), exc_info=True)
+                code = 1
+            os._exit(code)
+        children.append(pid)
+    pid, status = os.wait()
+    log_event(logging.ERROR, "worker_exited", worker=pid, status=status, action="stopping")
+    stop()
+    sys.exit(1)


 def main():
-    server = ThreadingHTTPServer((BIND, PORT), Handler)
-    sys.stderr.write(
-        f"snrc-resolve listening on {BIND}:{PORT}\n"
-        f"  RPC = {RPC}\n"
-        f"  Registries:\n"
+    setup_logging()
+    log_event(
+        logging.INFO,
+        "listening",
+        bind=BIND,
+        port=PORT,
+        workers=WORKERS,
+        rpc=public_endpoint(RPC),
+        registries=",".join(f"{tld}={addr or '-'}" for tld, addr in REGISTRIES.items()),
+        trusted_proxies=",".join(map(str, TRUSTED_PROXIES)) or None,
    )
-    for tld, addr in REGISTRIES.items():
-        sys.stderr.write(f"    .{tld:<8s} = {addr or '(not configured)'}\n")
-    sys.stderr.write("  GET /v2/resolve/<name>   GET /v1/resolve/<name>   GET /health\n")
-    try:
-        server.serve_forever()
-    except KeyboardInterrupt:
-        sys.stderr.write("\nshutting down\n")
-        server.server_close()
+    if WORKERS > 1:
+        supervise(WORKERS)
+    else:
+        signal.signal(signal.SIGTERM, stop_on)
+        signal.signal(signal.SIGINT, stop_on)
+        serve(reuse_port=False)


 if __name__ == "__main__":
@@ -1,15 +1,30 @@
 #!/usr/bin/env python3
 """Unit tests for snrc-resolve helpers.

-Run with `python3 -m unittest scripts/resolver/service/test_snrc_resolve.py`.
+Run with `uv run pytest` from scripts/resolver/service.
 """

 import contextlib
+import http.client
 import importlib.util
 import io
+import ipaddress
+import json
+import logging
 import os
+import queue
+import re
+import signal
+import socket
+import subprocess
+import sys
+import threading
 import time
 import unittest
+from http.server import BaseHTTPRequestHandler, ThreadingHTTPServer
+from urllib.error import HTTPError
+from urllib.parse import urlparse
+from urllib.request import Request, urlopen

 # snrc-resolve.py has a hyphen, so import it via importlib instead of `import`.
 _HERE = os.path.dirname(os.path.abspath(__file__))
@@ -636,6 +651,25 @@ class PricingTests(unittest.TestCase):
        self.assertEqual(body["basePrice"], self.BASE)


+class DecodePricesTests(unittest.TestCase):
+    def test_a_count_longer_than_the_answer_is_refused(self):
+        """The count comes from the oracle; decoding it unchecked could loop for ever."""
+        huge = "0x" + snrc.encode_uint(200) + snrc.encode_uint(0x40) + snrc.encode_uint(2**64)
+        outcome = []
+
+        def decode():
+            try:
+                snrc.decode_prices(huge)
+            except RuntimeError as e:
+                outcome.append(e)
+
+        worker = threading.Thread(target=decode, daemon=True)
+        worker.start()
+        worker.join(5)
+        self.assertFalse(worker.is_alive(), "decoding did not stop")
+        self.assertRegex(str(outcome[0]), "short response")
+
+
 class EnsOracleTests(unittest.TestCase):
    """.testing runs an ENS-shaped oracle: it prices in attoUSD per second and
    charges a premium on lapsed names that it does not expose."""
@@ -777,13 +811,17 @@ class ErrorCodeTests(unittest.TestCase):
                self.assertNotEqual(body["error"], body["message"])

    def test_an_upstream_failure_does_not_echo_the_exception(self):
-        with contextlib.redirect_stderr(io.StringIO()) as log:
+        with self.assertLogs("snrc_resolve", "WARNING") as logs:
            body = snrc.upstream_error(
                {"name": "alice.testing"},
                RuntimeError("http://user:[email protected]/kEy8 refused"),
            )
        # the operator still sees the detail in the log
-        self.assertIn("secret", log.getvalue())
+        [record] = logs.records
+        self.assertEqual(record.getMessage(), "upstream_error")
+        self.assertEqual(record.fields["name"], "alice.testing")
+        self.assertEqual(record.fields["error"], "RuntimeError")
+        self.assertIn("secret", record.fields["message"])
        self.assertEqual(body["error"], "upstreamError")
        self.assertIn("RuntimeError", body["message"])
        self.assertNotIn("secret", body["message"])
@@ -1035,5 +1073,797 @@ class RegistrationV2Tests(unittest.TestCase):
        self.assertEqual(res["lastBlockTs"], self.now)
        self.assertEqual(res["registration"]["type"], "available")

-if __name__ == "__main__":
-    unittest.main()
+
+@unittest.skipUnless(sys.platform.startswith("linux"), "Linux drops SYNs on a full accept queue")
+class ListenBacklogTests(unittest.TestCase):
+    """The smp-server opens a connection per lookup and gives up after 3 s, so a
+    burst the accept queue cannot hold fails: TCP retries a dropped SYN after 1 s."""
+
+    BURST = 50
+
+    def test_a_burst_of_connections_is_queued_while_the_server_is_busy(self):
+        # never accepts, so every connection must wait in the queue
+        server = snrc.ResolverServer(("127.0.0.1", 0), snrc.Handler)
+        clients = []
+        try:
+            for i in range(self.BURST):
+                c = socket.socket()
+                clients.append(c)
+                c.settimeout(0.5)
+                try:
+                    c.connect(server.server_address)
+                except TimeoutError:
+                    self.fail(f"connection {i + 1} of {self.BURST} was not queued")
+        finally:
+            for c in clients:
+                c.close()
+            server.server_close()
+
+
+def _word(value: int) -> bytes:
+    return value.to_bytes(32, "big")
+
+
+def _decode_aggregate3_calls(data: str):
+    """Multicall3.aggregate3 calldata back to (to, data) pairs, written apart
+    from the resolver's encoder so the two check each other."""
+    raw = bytes.fromhex(data[len(snrc.AGGREGATE3):])
+
+    def word(at):
+        return int.from_bytes(raw[at:at + 32], "big")
+
+    array = word(0)
+    base = array + 32
+    calls = []
+    for i in range(word(array)):
+        item = base + word(base + 32 * i)
+        call = item + word(item + 64)
+        calls.append(("0x" + raw[item + 12:item + 32].hex(), "0x" + raw[call + 32:call + 32 + word(call)].hex()))
+    return calls
+
+
+def _encode_aggregate3_results(results) -> str:
+    tuples = [
+        _word(int(ok)) + _word(0x40) + _word(len(data)) + data + b"\x00" * ((-len(data)) % 32)
+        for ok, data in results
+    ]
+    offsets, at = b"", 32 * len(tuples)
+    for t in tuples:
+        offsets += _word(at)
+        at += len(t)
+    return "0x" + (_word(0x20) + _word(len(tuples)) + offsets + b"".join(tuples)).hex()
+
+
+class FakeChain:
+    """Contract state for one registered name and one free name. Any other
+    call reverts, as a view function asked for something unset does."""
+
+    REGISTRY = "0x58fc46996d975c57883564648bda5206d1a0102b"
+    REGISTRAR = "0xef47eb4384b46c89e4482a677c2cbcbd2a6fd85a"
+    CONTROLLER = "0x281ca41311c2aa808c917c4674639d7567b75714"
+    ORACLE = "0x1e0c9a2b9d1a4c8f7b3e5d6a9c2f4b8e1d7a3c50"
+    OWNER = "0xd83bd7e0e6b8a4c1f2593a7b0c4e8d1a6f9b2c37"
+    RESOLVER = "0x80fa2b1c3d4e5f60718293a4b5c6d7e8f9012345"
+    GRACE = 90 * 86400
+    TEXTS = {"nickname": "Acme", "url": "https://acme.example", "simplex.channel": "https://a.example/c#1;https://b.example/c#2"}
+
+    def __init__(self):
+        self.now = int(time.time())
+        acme, free = snrc.label_token("acme"), snrc.label_token("free")
+        node = snrc.node_of("acme.testing")
+        abi_bytes = RegistrationV2Tests._abi_bytes
+        prices = RegistrationV2Tests._prices_return(RegistrationV2Tests())
+        self.answers = {
+            snrc.expires_call(self.REGISTRAR, acme): "0x" + snrc.encode_uint(self.now + 3600),
+            snrc.expires_call(self.REGISTRAR, free): "0x" + snrc.encode_uint(0),
+            snrc.grace_call(self.REGISTRAR): "0x" + snrc.encode_uint(self.GRACE),
+            snrc.label_call(self.REGISTRAR, acme): abi_bytes(b"acme"),
+            snrc.reserved_call(self.CONTROLLER, acme): "0x" + snrc.encode_uint(0),
+            snrc.reserved_call(self.CONTROLLER, free): "0x" + snrc.encode_uint(0),
+            snrc.resolver_call(self.REGISTRY, node): "0x" + snrc.encode_uint(int(self.RESOLVER, 16)),
+            snrc.owner_call(self.REGISTRY, node): "0x" + snrc.encode_uint(int(self.OWNER, 16)),
+            snrc.addr_call(self.RESOLVER, node, snrc.COIN_ETH): abi_bytes(bytes.fromhex(self.OWNER[2:])),
+            snrc.prices_call(self.CONTROLLER): "0x" + snrc.encode_uint(int(self.ORACLE, 16)),
+            snrc.prices_call(self.ORACLE): prices,
+            snrc.min_length_call(self.CONTROLLER): "0x" + snrc.encode_uint(3),
+        }
+        for key, value in self.TEXTS.items():
+            self.answers[snrc.text_call(self.RESOLVER, node, key)] = abi_bytes(value.encode())
+
+    def call(self, to, data):
+        answer = self.answers.get((to.lower(), data))
+        if answer is None:
+            raise RuntimeError("execution reverted")
+        return answer
+
+
+class FakeNode(ThreadingHTTPServer):
+    """A JSON-RPC node over HTTP/1.1 keep-alive, serving FakeChain, with
+    batches and Multicall3, each of which a test can take away."""
+
+    daemon_threads = True
+
+    def __init__(self):
+        super().__init__(("127.0.0.1", 0), _FakeNodeHandler)
+        self.chain = FakeChain()
+        self.block = 100
+        self.requests = 0
+        self.connections = 0
+        self.batch = True
+        self.multicall = True
+        self.multicall_null = False
+        self.status = 200
+        self.hang_up = False
+        self.drop_after_reply = False
+        threading.Thread(target=self.serve_forever, args=(0.05,), daemon=True).start()
+
+    @property
+    def url(self):
+        return f"http://127.0.0.1:{self.server_address[1]}/"
+
+    def stop(self):
+        self.shutdown()
+        self.server_close()
+
+    def answer(self, req):
+        out = {"jsonrpc": "2.0", "id": req.get("id")}
+        method, params = req["method"], req["params"]
+        if method == "eth_blockNumber":
+            out["result"] = hex(self.block)
+        elif method == "eth_getBlockByNumber":
+            out["result"] = {"number": hex(self.block), "timestamp": hex(self.chain.now)}
+        elif method == "eth_call" and params[0]["to"].lower() == snrc.MULTICALL.lower():
+            if not self.multicall:
+                out["error"] = {"code": -32000, "message": "no contract code"}
+            elif self.multicall_null:
+                out["result"] = None
+            else:
+                results = []
+                for to, data in _decode_aggregate3_calls(params[0]["data"]):
+                    try:
+                        results.append((True, bytes.fromhex(self.chain.call(to, data)[2:])))
+                    except RuntimeError:
+                        results.append((False, b""))
+                out["result"] = _encode_aggregate3_results(results)
+        elif method == "eth_call":
+            try:
+                out["result"] = self.chain.call(params[0]["to"], params[0]["data"])
+            except RuntimeError:
+                out["error"] = {"code": 3, "message": "execution reverted"}
+        else:
+            out["error"] = {"code": -32601, "message": "method not found"}
+        return out
+
+
+class _FakeNodeHandler(BaseHTTPRequestHandler):
+    protocol_version = "HTTP/1.1"
+
+    def setup(self):
+        super().setup()
+        # headers and body go out in separate writes, which Nagle holds for the client's delayed ACK
+        self.request.setsockopt(socket.IPPROTO_TCP, socket.TCP_NODELAY, 1)
+        self.server.connections += 1
+
+    def do_POST(self):  # noqa: N802 - http.server contract
+        request = json.loads(self.rfile.read(int(self.headers["Content-Length"])))
+        node = self.server
+        node.requests += 1
+        if node.hang_up:
+            self.close_connection = True
+            return
+        if node.status != 200:
+            reply = {"error": "unavailable"}
+        elif isinstance(request, list):
+            reply = [node.answer(r) for r in request] if node.batch else {"jsonrpc": "2.0", "id": None, "error": {"code": -32600, "message": "batch not supported"}}
+        else:
+            reply = node.answer(request)
+        data = json.dumps(reply).encode()
+        self.send_response(node.status)
+        self.send_header("Content-Type", "application/json")
+        self.send_header("Content-Length", str(len(data)))
+        self.end_headers()
+        self.wfile.write(data)
+        # closes without `Connection: close`, as a node dropping an idle connection does
+        self.close_connection = node.drop_after_reply
+
+    def log_message(self, fmt, *args):
+        pass
+
+
+class FakeNodeTestCase(unittest.TestCase):
+    """Points the resolver at a FakeNode and at FakeChain's contracts."""
+
+    def setUp(self):
+        self.node = FakeNode()
+        self._saved = (snrc.RPC, snrc.RPC_URL, snrc.REGISTRIES, snrc.REGISTRARS, snrc.CONTROLLERS)
+        snrc.RPC = self.node.url
+        snrc.RPC_URL = urlparse(snrc.RPC)
+        snrc.REGISTRIES = {"testing": FakeChain.REGISTRY, "simplex": ""}
+        snrc.REGISTRARS = {"testing": FakeChain.REGISTRAR}
+        snrc.CONTROLLERS = {"testing": FakeChain.CONTROLLER}
+        snrc._multicall_failed_logged = False
+        self._drain_pool()
+
+    def tearDown(self):
+        self._drain_pool()
+        snrc.RPC, snrc.RPC_URL, snrc.REGISTRIES, snrc.REGISTRARS, snrc.CONTROLLERS = self._saved
+        self.node.stop()
+
+    def _drain_pool(self):
+        while not snrc._rpc_pool.empty():
+            snrc._rpc_pool.get_nowait().close()
+
+    def requests_made(self, action):
+        before = self.node.requests
+        result = action()
+        return result, self.node.requests - before
+
+
+class RpcTransportTests(FakeNodeTestCase):
+    """A lookup makes several reads, and a new connection per read costs CPU
+    and leaves a TIME_WAIT socket each, which exhausts local ports under load."""
+
+    def test_reads_share_one_connection(self):
+        for _ in range(18):
+            self.assertEqual(snrc.rpc("eth_blockNumber", []), hex(self.node.block))
+        self.assertEqual(self.node.connections, 1)
+
+    def test_a_connection_the_node_closed_is_replaced(self):
+        self.node.drop_after_reply = True
+        for _ in range(3):
+            self.assertEqual(snrc.rpc("eth_blockNumber", []), hex(self.node.block))
+        self.assertEqual(self.node.connections, 3)
+
+    def test_a_fresh_connection_that_fails_is_not_retried(self):
+        """Only a pooled connection can be stale; a new one failing means the
+        node is down, and resending would only double the wait."""
+        self.node.hang_up = True
+        with self.assertRaises(ConnectionError):
+            snrc.rpc("eth_blockNumber", [])
+        self.assertEqual(self.node.requests, 1)
+
+    def test_a_node_failure_is_not_a_reverted_call(self):
+        """Callers read RuntimeError as the call reverting and fall back to an
+        empty value, so a node failure must not look like one."""
+        self.node.status = 502
+        with self.assertRaises(HTTPError) as cm:
+            snrc.rpc("eth_blockNumber", [])
+        self.assertNotIsInstance(cm.exception, RuntimeError)
+        self.assertEqual(cm.exception.code, 502)
+
+    def test_a_reverted_call_is_a_runtime_error_and_keeps_the_connection(self):
+        with self.assertRaises(RuntimeError):
+            snrc.eth_call("0x" + "11" * 20, "0xdeadbeef")
+        snrc.rpc("eth_blockNumber", [])
+        self.assertEqual(self.node.connections, 1)
+
+
+class RpcPoolTests(FakeNodeTestCase):
+    def test_connections_beyond_the_pool_are_closed_after_use(self):
+        """Every worker would otherwise keep its peak concurrency open to the node."""
+        saved, snrc._rpc_pool = snrc._rpc_pool, queue.LifoQueue(maxsize=1)
+        try:
+            body = json.dumps({"jsonrpc": "2.0", "id": 1, "method": "eth_blockNumber", "params": []}).encode()
+            kept, extra = snrc._new_rpc_connection(), snrc._new_rpc_connection()
+            snrc._post_pooled(kept, body)
+            # returning a connection to a full pool must not wait for a free slot
+            done = threading.Thread(target=snrc._post_pooled, args=(extra, body), daemon=True)
+            done.start()
+            done.join(5)
+            self.assertFalse(done.is_alive(), "returning a connection to a full pool blocked")
+            self.assertEqual(snrc._rpc_pool.qsize(), 1)
+            self.assertIsNotNone(kept.sock)
+            self.assertIsNone(extra.sock)
+        finally:
+            while not snrc._rpc_pool.empty():
+                snrc._rpc_pool.get_nowait().close()
+            snrc._rpc_pool = saved
+
+
+class BatchedReadsTests(FakeNodeTestCase):
+    """Inside a request a round of reads is one round trip, and its contract
+    reads one multicall, because a node runs the calls of a JSON-RPC batch one
+    after another. Answers must be exactly those of reading one call at a time."""
+
+    def batched(self, answer, name):
+        def action():
+            with snrc.request_reads():
+                return answer(name)
+        return self.requests_made(action)
+
+    def assert_same_answer(self, answer, name, round_trips):
+        one_by_one, one_by_one_trips = self.requests_made(lambda: answer(name))
+        batched, batched_trips = self.batched(answer, name)
+        self.assertEqual(batched, one_by_one)
+        self.assertEqual(batched_trips, round_trips)
+        self.assertGreater(one_by_one_trips, round_trips)
+        return batched
+
+    def test_a_registered_name_takes_two_round_trips(self):
+        status, body = self.assert_same_answer(snrc.registration, "acme.testing", 2)
+        record = body["registration"]["nameRecord"]
+        self.assertEqual(record["nickname"], "Acme")
+        self.assertEqual(record["simplexChannel"], ["https://a.example/c#1", "https://b.example/c#2"])
+        self.assertIsNone(record["btc"])
+
+    def test_a_hashed_query_is_named_from_the_same_round_trip(self):
+        hashed = "[" + snrc.keccak(b"acme").hex() + "].testing"
+        status, body = self.assert_same_answer(snrc.registration, hashed, 2)
+        self.assertEqual(body["registration"]["nameRecord"]["name"], "acme.testing")
+
+    def test_an_available_name_is_priced_in_three_round_trips(self):
+        status, body = self.assert_same_answer(snrc.registration, "free.testing", 3)
+        self.assertEqual(body["registration"]["type"], "available")
+
+    def test_v1_answers_the_same(self):
+        self.assert_same_answer(snrc.resolve, "acme.testing", 2)
+
+    def test_without_multicall_a_round_is_still_one_batch(self):
+        self.node.multicall = False
+        with self.assertLogs("snrc_resolve", "WARNING") as logs:
+            self.assert_same_answer(snrc.registration, "acme.testing", 4)
+        [record] = logs.records
+        self.assertEqual((record.getMessage(), record.fields["fallback"]), ("multicall_unavailable", "batch"))
+
+    def test_a_multicall_without_a_result_falls_back_to_a_batch(self):
+        self.node.multicall_null = True
+        with self.assertLogs("snrc_resolve", "WARNING") as logs:
+            self.assert_same_answer(snrc.registration, "acme.testing", 4)
+        self.assertEqual([r.getMessage() for r in logs.records], ["multicall_unavailable"])
+
+    def test_an_answer_with_neither_result_nor_error_is_not_taken_as_one(self):
+        reads = {}
+        snrc._remember(reads, [("eth_blockNumber", [])], [{"jsonrpc": "2.0", "id": 0}])
+        self.assertEqual(reads, {})
+
+    def test_a_node_that_does_not_batch_is_read_one_call_at_a_time(self):
+        self.node.batch = False
+        one_by_one, one_by_one_trips = self.requests_made(lambda: snrc.registration("acme.testing"))
+        with self.assertNoLogs("snrc_resolve"):
+            batched, batched_trips = self.batched(snrc.registration, "acme.testing")
+        self.assertEqual(batched, one_by_one)
+        # one refused batch per round, then the reads the batch would have made
+        self.assertEqual(batched_trips, one_by_one_trips + 2)
+
+    def test_a_read_reverted_in_the_multicall_is_a_reverted_call(self):
+        with snrc.request_reads():
+            snrc.prefetch([snrc.eth_call_read(*snrc.grace_call(FakeChain.REGISTRAR)), snrc.eth_call_read(FakeChain.REGISTRY, "0xdeadbeef")])
+            _, trips = self.requests_made(lambda: self.assertRaises(RuntimeError, snrc.eth_call, FakeChain.REGISTRY, "0xdeadbeef"))
+        self.assertEqual(trips, 0)
+
+    def test_outside_a_request_nothing_is_prefetched(self):
+        _, trips = self.requests_made(lambda: snrc.prefetch(snrc.lookup_reads("acme.testing")))
+        self.assertEqual(trips, 0)
+
+
+class Aggregate3Tests(unittest.TestCase):
+    def test_calls_are_encoded_as_multicall3_reads_them(self):
+        calls = [(FakeChain.REGISTRY, "0x0178b8bf" + "11" * 32), (FakeChain.RESOLVER, "0x59d1d43c" + "22" * 100)]
+        data = snrc.encode_aggregate3(calls)
+        self.assertTrue(data.startswith(snrc.AGGREGATE3))
+        self.assertEqual(_decode_aggregate3_calls(data), calls)
+
+    def test_results_are_decoded_with_their_success_flags(self):
+        results = [(True, b"\x01" * 40), (False, b""), (True, b"")]
+        self.assertEqual(snrc.decode_aggregate3(_encode_aggregate3_results(results)), results)
+
+    def test_a_truncated_answer_is_refused(self):
+        whole = _encode_aggregate3_results([(True, b"\x01" * 40)])
+        with self.assertRaises(ValueError):
+            snrc.decode_aggregate3(whole[:-64])
+        with self.assertRaises(ValueError):
+            snrc.decode_aggregate3("0x")
+
+
+class RequestLogTests(unittest.TestCase):
+    """Each request is one event with the client it came from, behind a reverse
+    proxy the client the proxy names rather than the proxy itself."""
+
+    def setUp(self):
+        self.server = snrc.ResolverServer(("127.0.0.1", 0), snrc.Handler)
+        threading.Thread(target=self.server.serve_forever, args=(0.05,), daemon=True).start()
+        self._saved = snrc.TRUSTED_PROXIES
+
+    def tearDown(self):
+        snrc.TRUSTED_PROXIES = self._saved
+        self.server.shutdown()
+        self.server.server_close()
+
+    def request(self, path, headers=None, level="INFO"):
+        url = f"http://127.0.0.1:{self.server.server_address[1]}{path}"
+        with self.assertLogs("snrc_resolve", level) as logs:
+            try:
+                urlopen(Request(url, headers=headers or {}), timeout=5).read()
+            except HTTPError:
+                pass
+            deadline = time.monotonic() + 2
+            while not any(r.getMessage() == "request" for r in logs.records) and time.monotonic() < deadline:
+                time.sleep(0.01)
+        [record] = [r for r in logs.records if r.getMessage() == "request"]
+        return record
+
+    def test_a_request_is_logged_with_its_outcome(self):
+        record = self.request("/v2/resolve/x.simplex")
+        fields = record.fields
+        self.assertEqual(record.levelname, "INFO")
+        self.assertEqual(
+            (fields["client"], fields["method"], fields["path"], fields["status"], fields["worker"]),
+            ("127.0.0.1", "GET", "/v2/resolve/x.simplex", 400, os.getpid()),
+        )
+        self.assertGreater(fields["bytes"], 0)
+        self.assertGreaterEqual(fields["ms"], 0)
+
+    def test_a_trusted_proxy_names_the_client(self):
+        snrc.TRUSTED_PROXIES = (ipaddress.ip_network("127.0.0.1/32"),)
+        record = self.request("/v2/resolve/x.simplex", {"X-Forwarded-For": "203.0.113.7"})
+        self.assertEqual(record.fields["client"], "203.0.113.7")
+
+    def test_any_other_peer_cannot_name_itself(self):
+        record = self.request("/v2/resolve/x.simplex", {"X-Forwarded-For": "203.0.113.7"})
+        self.assertEqual(record.fields["client"], "127.0.0.1")
+
+    def test_a_bad_request_is_not_logged_with_the_previous_ones_fields(self):
+        """On a kept-alive connection the handler still held the last request's path and size."""
+        with self.assertLogs("snrc_resolve", "INFO") as logs:
+            with socket.create_connection(self.server.server_address, timeout=5) as sock:
+                sock.sendall(b"GET /v2/resolve/x.simplex HTTP/1.1\r\nHost: x\r\n\r\n")
+                sock.recv(65536)
+                sock.sendall(b"BOGUS\r\n\r\n")
+                while sock.recv(65536):
+                    pass
+        first, second = [r for r in logs.records if r.getMessage() == "request"]
+        self.assertEqual(first.fields["path"], "/v2/resolve/x.simplex")
+        self.assertEqual((second.fields["status"], second.fields["path"], second.fields["bytes"], second.fields["ms"]), (400, None, None, None))
+
+    def test_health_checks_are_logged_only_at_debug(self):
+        """The container checks /health every 30 s."""
+        record = self.request("/health", level="DEBUG")
+        self.assertEqual(record.levelname, "DEBUG")
+
+
+class RequestBodyTests(unittest.TestCase):
+    """Behind a reverse proxy that reuses connections, a body left unread would be
+    answered as another request, and that answer given to the proxy's next client."""
+
+    def setUp(self):
+        self.server = snrc.ResolverServer(("127.0.0.1", 0), snrc.Handler)
+        threading.Thread(target=self.server.serve_forever, args=(0.05,), daemon=True).start()
+        self._log = contextlib.redirect_stderr(io.StringIO())
+        self._log.__enter__()
+
+    def tearDown(self):
+        self._log.__exit__(None, None, None)
+        self.server.shutdown()
+        self.server.server_close()
+
+    def exchange(self, head: bytes, body: bytes = b"") -> bytes:
+        with socket.create_connection(self.server.server_address, timeout=5) as sock:
+            sock.sendall(head + body)
+            data = b""
+            while chunk := sock.recv(65536):
+                data += chunk
+                if data.count(b"HTTP/1.1 ") > 1:
+                    break
+            return data
+
+    SMUGGLED = b"GET /v2/resolve/y.simplex HTTP/1.1\r\nHost: x\r\n\r\n"
+
+    def test_a_body_is_refused_and_the_connection_closed(self):
+        data = self.exchange(b"GET /v2/resolve/x.simplex HTTP/1.1\r\nHost: x\r\nContent-Length: %d\r\n\r\n" % len(self.SMUGGLED), self.SMUGGLED)
+        self.assertEqual(data.count(b"HTTP/1.1 "), 1)
+        self.assertIn(b"HTTP/1.1 400 ", data)
+        self.assertIn(b"Connection: close", data)
+        self.assertNotIn(b"y.simplex", data)
+
+    def test_a_length_after_a_malformed_header_line_is_still_seen(self):
+        """Python stops parsing headers at a malformed line and keeps the rest as payload."""
+        data = self.exchange(b"GET /v2/resolve/x.simplex HTTP/1.1\r\nX-Junk : 1\r\nContent-Length: %d\r\n\r\n" % len(self.SMUGGLED), self.SMUGGLED)
+        self.assertEqual(data.count(b"HTTP/1.1 "), 1)
+        self.assertIn(b"unexpectedBody", data)
+        self.assertNotIn(b"y.simplex", data)
+
+    def test_a_chunked_body_is_refused_and_the_connection_closed(self):
+        chunked = b"%x\r\n" % len(self.SMUGGLED) + self.SMUGGLED + b"\r\n0\r\n\r\n"
+        data = self.exchange(b"GET /v2/resolve/x.simplex HTTP/1.1\r\nHost: x\r\nTransfer-Encoding: chunked\r\n\r\n", chunked)
+        self.assertEqual(data.count(b"HTTP/1.1 "), 1)
+        self.assertNotIn(b"y.simplex", data)
+
+    def test_an_empty_body_keeps_the_connection(self):
+        conn = http.client.HTTPConnection(*self.server.server_address, timeout=5)
+        answers = []
+        for _ in range(2):
+            conn.request("GET", "/v2/resolve/x.simplex", headers={"Content-Length": "0"})
+            res = conn.getresponse()
+            answers.append((res.status, json.loads(res.read())["error"], conn.sock))
+        conn.close()
+        self.assertEqual([a[:2] for a in answers], [(400, "tldNotConfigured")] * 2)
+        self.assertIs(answers[0][2], answers[1][2])
+
+
+class PublicEndpointTests(unittest.TestCase):
+    def test_credentials_path_and_query_are_not_shown(self):
+        self.assertEqual(snrc.public_endpoint("https://user:[email protected]:8443/v2/KEY?apikey=K"), "https://rpc.example:8443")
+
+    def test_a_plain_endpoint_is_unchanged(self):
+        self.assertEqual(snrc.public_endpoint("http://reth:8545"), "http://reth:8545")
+
+    def test_an_ipv6_host_keeps_its_brackets(self):
+        self.assertEqual(snrc.public_endpoint("http://u:p@[::1]:8545/key"), "http://[::1]:8545")
+
+    def test_a_malformed_port_does_not_break_health(self):
+        self.assertEqual(snrc.public_endpoint("http://reth:port"), "http://reth:port")
+
+
+class ClientAddressTests(unittest.TestCase):
+    PROXY = "172.18.0.1"
+
+    def setUp(self):
+        self._saved = snrc.TRUSTED_PROXIES
+        snrc.TRUSTED_PROXIES = (ipaddress.ip_network("172.16.0.0/12"),)
+
+    def tearDown(self):
+        snrc.TRUSTED_PROXIES = self._saved
+
+    def test_a_peer_that_is_no_proxy_is_the_client(self):
+        self.assertEqual(snrc.client_address("198.51.100.9", "203.0.113.7"), "198.51.100.9")
+
+    def test_without_the_header_the_proxy_is_the_client(self):
+        self.assertEqual(snrc.client_address(self.PROXY, None), self.PROXY)
+
+    def test_the_address_the_proxy_added_is_the_client(self):
+        self.assertEqual(snrc.client_address(self.PROXY, "203.0.113.7"), "203.0.113.7")
+
+    def test_addresses_a_client_sent_itself_are_not_believed(self):
+        """A proxy appends the address it saw, so only the last untrusted one is known."""
+        self.assertEqual(snrc.client_address(self.PROXY, "6.6.6.6, 203.0.113.7"), "203.0.113.7")
+
+    def test_trusted_proxies_in_a_chain_are_skipped(self):
+        self.assertEqual(snrc.client_address(self.PROXY, "203.0.113.7, 172.18.0.5"), "203.0.113.7")
+
+    def test_an_address_that_does_not_parse_is_not_believed(self):
+        self.assertEqual(snrc.client_address(self.PROXY, "203.0.113.7, not-an-ip"), self.PROXY)
+
+    def test_an_ipv4_mapped_peer_is_matched_as_ipv4(self):
+        self.assertEqual(snrc.client_address("::ffff:172.18.0.1", "203.0.113.7"), "203.0.113.7")
+
+    def test_an_ipv6_client_is_kept(self):
+        self.assertEqual(snrc.client_address(self.PROXY, "2001:db8::7"), "2001:db8::7")
+
+
+class RequestErrorTests(unittest.TestCase):
+    def setUp(self):
+        self.server = snrc.ResolverServer(("127.0.0.1", 0), snrc.Handler)
+
+    def tearDown(self):
+        self.server.server_close()
+
+    def test_a_client_that_hung_up_is_a_warning_without_a_traceback(self):
+        """What an smp-server that gave up after its timeout leaves behind."""
+        with self.assertLogs("snrc_resolve", "WARNING") as logs:
+            try:
+                raise BrokenPipeError
+            except BrokenPipeError:
+                self.server.handle_error(None, ("198.51.100.9", 4000))
+        [record] = logs.records
+        self.assertEqual((record.levelname, record.getMessage(), record.fields["error"]), ("WARNING", "client_gone", "BrokenPipeError"))
+        self.assertIsNone(record.exc_info)
+
+    def test_a_failure_is_an_error_with_its_traceback(self):
+        with self.assertLogs("snrc_resolve", "ERROR") as logs:
+            try:
+                raise KeyError("boom")
+            except KeyError:
+                self.server.handle_error(None, ("198.51.100.9", 4000))
+        [record] = logs.records
+        self.assertEqual((record.getMessage(), record.fields["client"]), ("request_failed", "198.51.100.9"))
+        self.assertIsNotNone(record.exc_info)
+
+
+class KeepAliveTests(unittest.TestCase):
+    """The smp-server keeps a resolver connection only after an HTTP/1.1
+    response, and otherwise connects for every lookup."""
+
+    def setUp(self):
+        self.server = snrc.ResolverServer(("127.0.0.1", 0), snrc.Handler)
+        threading.Thread(target=self.server.serve_forever, args=(0.05,), daemon=True).start()
+        self._saved_timeout = snrc.Handler.timeout
+        self._log = contextlib.redirect_stderr(io.StringIO())
+        self._log.__enter__()
+
+    def tearDown(self):
+        self._log.__exit__(None, None, None)
+        snrc.Handler.timeout = self._saved_timeout
+        self.server.shutdown()
+        self.server.server_close()
+
+    def test_requests_share_one_connection_without_delay(self):
+        conn = http.client.HTTPConnection(*self.server.server_address, timeout=5)
+        start = time.monotonic()
+        for i in range(20):
+            conn.request("GET", "/v2/resolve/x.simplex")
+            res = conn.getresponse()
+            res.read()
+            self.assertEqual((res.version, res.status), (11, 400))
+            if i == 0:
+                sock = conn.sock
+            self.assertIs(conn.sock, sock)
+        conn.close()
+        # a response held by Nagle for the delayed ACK takes ~40 ms, 20 of them over 0.8 s
+        self.assertLess(time.monotonic() - start, 0.5)
+
+    def test_idle_connections_outlast_the_smp_servers(self):
+        """http-client drops a connection idle for 30 s, checked every 5 s. A
+        resolver that closed sooner would race the client reusing it, and one
+        that never closed would keep a thread per dead connection."""
+        self.assertIsNotNone(self._saved_timeout)
+        self.assertGreater(self._saved_timeout, 35)
+
+    def test_an_idle_connection_is_closed(self):
+        snrc.Handler.timeout = 0.2
+        with socket.create_connection(self.server.server_address, timeout=5) as sock:
+            time.sleep(0.5)
+            self.assertEqual(sock.recv(1), b"")
+
+
+@unittest.skipUnless(sys.platform.startswith("linux"), "reads worker processes from /proc")
+class WorkerProcessesTests(unittest.TestCase):
+    """Workers share the port, and the service stops as a whole, so the
+    container restarts rather than serving on fewer workers."""
+
+    def setUp(self):
+        self.node = FakeNode()
+        with socket.socket() as s:
+            s.bind(("127.0.0.1", 0))
+            self.port = s.getsockname()[1]
+        env = dict(os.environ, SNRC_RPC=self.node.url, SNRC_BIND="127.0.0.1", SNRC_PORT=str(self.port), SNRC_WORKERS="2",
+                   SNRC_REGISTRY_TESTING=FakeChain.REGISTRY, SNRC_REGISTRAR_TESTING=FakeChain.REGISTRAR, SNRC_CONTROLLER_TESTING=FakeChain.CONTROLLER)
+        self.service = subprocess.Popen([sys.executable, os.path.join(_HERE, "snrc-resolve.py")], env=env, stderr=subprocess.PIPE, text=True)
+        self.workers = self._wait_for_workers(2)
+
+    def tearDown(self):
+        if self.service.poll() is None:
+            self.service.kill()
+            self.service.wait()
+        self.service.stderr.close()
+        for pid in self.workers:
+            with contextlib.suppress(ProcessLookupError):
+                os.kill(pid, signal.SIGKILL)
+        self.node.stop()
+
+    def _wait_for_workers(self, count):
+        deadline = time.monotonic() + 10
+        while time.monotonic() < deadline:
+            workers = [int(p) for p in os.listdir("/proc") if p.isdigit() and self._parent(p) == self.service.pid]
+            if len(workers) == count and self._serving():
+                return workers
+            time.sleep(0.05)
+        self.fail("workers did not start")
+
+    @staticmethod
+    def _parent(pid):
+        try:
+            with open(f"/proc/{pid}/stat") as f:
+                return int(f.read().rsplit(")", 1)[1].split()[1])
+        except (FileNotFoundError, ProcessLookupError):
+            return None
+
+    def _serving(self):
+        try:
+            with socket.create_connection(("127.0.0.1", self.port), timeout=1):
+                return True
+        except OSError:
+            return False
+
+    def _gone(self, pid):
+        deadline = time.monotonic() + 5
+        while time.monotonic() < deadline:
+            if self._parent(pid) != self.service.pid:
+                return True
+            time.sleep(0.05)
+        return False
+
+    def test_workers_answer_on_the_shared_port(self):
+        for _ in range(20):
+            with urlopen(f"http://127.0.0.1:{self.port}/v2/resolve/acme.testing", timeout=5) as res:
+                self.assertEqual(json.loads(res.read())["registration"]["type"], "registered")
+
+    def test_stopping_the_service_stops_every_worker(self):
+        self.service.send_signal(signal.SIGTERM)
+        self.assertEqual(self.service.wait(timeout=5), 0)
+        self.assertTrue(all(self._gone(pid) for pid in self.workers))
+        self.assertRegex(self.service.stderr.read(), r"INFO  stopping  signal=SIGTERM")
+
+    def test_a_worker_exiting_stops_the_service(self):
+        os.kill(self.workers[0], signal.SIGKILL)
+        self.assertEqual(self.service.wait(timeout=5), 1)
+        self.assertTrue(self._gone(self.workers[1]))
+
+
+TIME = r"\d{4}-\d\d-\d\dT\d\d:\d\d:\d\d\.\d{3}Z"
+
+
+class LogTestCase(unittest.TestCase):
+    def setUp(self):
+        self._saved = (snrc.LOG_FORMAT, snrc.LOG_COLOR, snrc.LOG_LEVEL)
+        snrc.LOG_FORMAT, snrc.LOG_COLOR, snrc.LOG_LEVEL = "text", "never", "info"
+        self.out = io.StringIO()
+
+    def tearDown(self):
+        snrc.LOG_FORMAT, snrc.LOG_COLOR, snrc.LOG_LEVEL = self._saved
+        snrc.LOGGER.handlers[:] = []
+        snrc.LOGGER.setLevel(logging.NOTSET)
+        snrc.LOGGER.propagate = True
+
+    def emit(self, level=logging.INFO, name="request", **fields):
+        snrc.setup_logging(self.out)
+        snrc.log_event(level, name, **fields)
+        return self.out.getvalue()
+
+
+class TextFormatTests(LogTestCase):
+    def test_a_line_is_utc_time_level_event_and_fields(self):
+        line = self.emit(client="203.0.113.7", path="/v2/resolve/[4fdd].testing", status=200, ms=7)
+        self.assertRegex(line, rf"^{TIME} INFO  request  client=203\.0\.113\.7 path=/v2/resolve/\[4fdd\]\.testing status=200 ms=7\n$")
+
+    def test_values_that_would_be_misread_are_quoted(self):
+        line = self.emit(message='says "hi" here', empty="", missing=None, eq="a=b")
+        self.assertIn('message="says \\"hi\\" here" empty="" missing=- eq="a=b"', line)
+
+    def test_levels_are_named_in_five_columns(self):
+        self.assertRegex(self.emit(logging.WARNING, "upstream_error"), rf"^{TIME} WARN  upstream_error\n$")
+
+    def test_below_the_configured_level_nothing_is_written(self):
+        self.assertEqual(self.emit(logging.DEBUG), "")
+
+    def test_an_exception_follows_its_line(self):
+        snrc.setup_logging(self.out)
+        try:
+            raise KeyError("boom")
+        except KeyError:
+            snrc.log_event(logging.ERROR, "request_failed", exc_info=True)
+        self.assertRegex(self.out.getvalue(), rf"(?s)^{TIME} ERROR request_failed\nTraceback .*KeyError: 'boom'\n$")
+
+
+class ColorTests(LogTestCase):
+    def test_colours_mark_the_level_and_the_status_class(self):
+        snrc.LOG_COLOR = "always"
+        line = self.emit(status=503)
+        self.assertIn("\033[32mINFO ", line)
+        self.assertIn("\033[31m503\033[0m", line)
+
+    def test_auto_leaves_output_that_is_no_terminal_plain(self):
+        snrc.LOG_COLOR = "auto"
+        self.assertNotIn("\033[", self.emit(status=200))
+
+    def test_never_is_plain(self):
+        self.assertNotIn("\033[", self.emit(status=200))
+
+
+class JsonFormatTests(LogTestCase):
+    def test_a_line_is_one_json_object(self):
+        snrc.LOG_FORMAT = "json"
+        record = json.loads(self.emit(client="203.0.113.7", status=200, missing=None))
+        self.assertRegex(record.pop("time"), rf"^{TIME}$")
+        self.assertEqual(record, {"level": "info", "event": "request", "client": "203.0.113.7", "status": 200, "missing": None})
+
+    def test_an_exception_is_a_field(self):
+        snrc.LOG_FORMAT = "json"
+        snrc.setup_logging(self.out)
+        try:
+            raise KeyError("boom")
+        except KeyError:
+            snrc.log_event(logging.ERROR, "request_failed", exc_info=True)
+        self.assertIn("KeyError: 'boom'", json.loads(self.out.getvalue())["exception"])
+
+
+class SetupTests(LogTestCase):
+    def test_unknown_settings_are_refused_at_start(self):
+        for setting, value in (("LOG_FORMAT", "yaml"), ("LOG_COLOR", "sometimes"), ("LOG_LEVEL", "loud")):
+            with self.subTest(setting=setting):
+                saved = getattr(snrc, setting)
+                setattr(snrc, setting, value)
+                try:
+                    with self.assertRaisesRegex(ValueError, re.escape(f"SNRC_{setting}")):
+                        snrc.setup_logging(self.out)
+                finally:
+                    setattr(snrc, setting, saved)
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+]
+
+[[package]]
+name = "snrc-resolve"
+version = "0.1.0"
+source = { virtual = "." }
+dependencies = [
+    { name = "eth-hash", extra = ["pycryptodome"] },
+]
+
+[package.dev-dependencies]
+dev = [
+    { name = "pytest" },
+    { name = "ruff" },
+]
+
+[package.metadata]
+requires-dist = [{ name = "eth-hash", extras = ["pycryptodome"], specifier = ">=0.7" }]
+
+[package.metadata.requires-dev]
+dev = [
+    { name = "pytest", specifier = ">=8" },
+    { name = "ruff", specifier = ">=0.6" },
+]
@@ -1,7 +1,7 @@
 cabal-version: 3.0

 name:           simplexmq
-version:        7.1.0.8
+version:        7.1.0.11
 synopsis:       SimpleXMQ message broker
 description:    This package includes <./docs/Simplex-Messaging-Server.html server>,
                <./docs/Simplex-Messaging-Client.html client> and
@@ -195,6 +195,8 @@ library
          Simplex.Messaging.Agent.Store.Postgres.Migrations.M20260712_address_dr_rpc
          Simplex.Messaging.Agent.Store.Postgres.Migrations.M20260823_snd_files_entitlement
          Simplex.Messaging.Agent.Store.Postgres.Migrations.M20260919_ratchet_verify_codes
+          Simplex.Messaging.Agent.Store.Postgres.Migrations.M20260929_ratchet_indexes
+          Simplex.Messaging.Agent.Store.Postgres.Migrations.M20261008_rcv_switch_status
  else
      exposed-modules:
          Simplex.Messaging.Agent.Store.SQLite
@@ -250,6 +252,9 @@ library
          Simplex.Messaging.Agent.Store.SQLite.Migrations.M20260712_address_dr_rpc
          Simplex.Messaging.Agent.Store.SQLite.Migrations.M20260823_snd_files_entitlement
          Simplex.Messaging.Agent.Store.SQLite.Migrations.M20260919_ratchet_verify_codes
+          Simplex.Messaging.Agent.Store.SQLite.Migrations.M20260929_ratchet_indexes
+          Simplex.Messaging.Agent.Store.SQLite.Migrations.M20261005_commands_autoincrement
+          Simplex.Messaging.Agent.Store.SQLite.Migrations.M20261008_rcv_switch_status
          Simplex.Messaging.Agent.Store.SQLite.Util
  if flag(client_postgres) || flag(server_postgres)
      exposed-modules:
@@ -271,7 +276,6 @@ library
          Simplex.FileTransfer.Server.Store
          Simplex.FileTransfer.Server.StoreLog
          Simplex.Messaging.Server
-          Simplex.Messaging.Server.AddressStats
          Simplex.Messaging.Server.CLI
          Simplex.Messaging.Server.Control
          Simplex.Messaging.Server.Env.STM
@@ -543,7 +547,6 @@ test-suite simplexmq-test
      AgentTests.ServerChoice
      AgentTests.ShortLinkTests
      CLITests
-      CoreTests.AddressStatsTests
      CoreTests.BatchingTests
      CoreTests.CryptoFileTests
      CoreTests.CryptoTests
@@ -599,7 +602,7 @@ test-suite simplexmq-test
  default-extensions:
      StrictData
  -- add -fhpc to ghc-options to run tests with coverage
-  ghc-options: -Weverything -Wno-missing-exported-signatures -Wno-missing-import-lists -Wno-missed-specialisations -Wno-all-missed-specialisations -Wno-unsafe -Wno-safe -Wno-missing-local-signatures -Wno-missing-kind-signatures -Wno-missing-deriving-strategies -Wno-monomorphism-restriction -Wno-prepositive-qualified-module -Wno-implicit-prelude -Wno-missing-safe-haskell-mode -Wno-missing-export-lists -Wno-partial-fields -Wcompat -Werror=incomplete-record-updates -Werror=incomplete-patterns -Werror=incomplete-uni-patterns -Werror=missing-methods -Werror=tabs -Wredundant-constraints -Wincomplete-record-updates -Wunused-type-patterns -O2 -threaded -rtsopts -with-rtsopts=-A64M -with-rtsopts=-N1
+  ghc-options: -Weverything -Wno-missing-exported-signatures -Wno-missing-import-lists -Wno-missed-specialisations -Wno-all-missed-specialisations -Wno-unsafe -Wno-safe -Wno-missing-local-signatures -Wno-missing-kind-signatures -Wno-missing-deriving-strategies -Wno-monomorphism-restriction -Wno-prepositive-qualified-module -Wno-implicit-prelude -Wno-missing-safe-haskell-mode -Wno-missing-export-lists -Wno-partial-fields -Wcompat -Werror=incomplete-record-updates -Werror=incomplete-patterns -Werror=incomplete-uni-patterns -Werror=missing-methods -Werror=tabs -Wredundant-constraints -Wincomplete-record-updates -Wunused-type-patterns -O2 -threaded -rtsopts "-with-rtsopts=-A64M -N1"
  build-depends:
      base
    , aeson
@@ -637,7 +640,6 @@ test-suite simplexmq-test
    , stm
    , text
    , time
-    , timeit ==2.0.*
    , tls >=1.9.0 && <1.10
    , transformers
    , unliftio
@@ -568,9 +568,10 @@ runXFTPSndWorker c srv Worker {doWork} = do
      notify c sndFileEntityId $ SFPROG uploaded total
      when complete $ do
        (sndDescr, rcvDescrs) <- sndFileToDescrs sf
+        flip catchAllErrors (\e -> logError $ "XFTP snd worker error: " <> tshow e) $ do
+          lift . forM_ prefixPath $ removePath <=< toFSFilePath
+          withStore' c $ \db -> updateSndFileComplete db sndFileId
        notify c sndFileEntityId $ SFDONE sndDescr rcvDescrs (sndFileExpiresAt chunks)
-        lift . forM_ prefixPath $ removePath <=< toFSFilePath
-        withStore' c $ \db -> updateSndFileComplete db sndFileId
      where
        addRecipients :: SndFileChunk -> SndFileChunkReplica -> AM SndFileChunkReplica
        addRecipients ch@SndFileChunk {numRecipients} cr@SndFileChunkReplica {sndChunkReplicaId, rcvIdsKeys}
@@ -80,7 +80,7 @@ import Simplex.Messaging.Protocol
    tParse,
  )
 import Simplex.Messaging.Transport (THandleParams (..), TransportError (..), TransportPeer (..))
-import Simplex.Messaging.Util ((<$?>))
+import Simplex.Messaging.Util (eitherToMaybe, (<$?>))

 xftpBlockSize :: Int
 xftpBlockSize = 16384
@@ -383,7 +383,7 @@ checkParty' c = case testEquality (sFileParty @p) (sFileParty @p') of
 xftpEncodeAuthTransmission :: ProtocolEncoding XFTPVersion XFTPErrorType c => THandleParams XFTPVersion 'TClient -> C.APrivateAuthKey -> Transmission c -> Either TransportError ByteString
 xftpEncodeAuthTransmission thParams@THandleParams {thAuth} pKey t@(corrId, _, _) = do
  let TransmissionForAuth {tForAuth, tToSend} = encodeTransmissionForAuth thParams t
-  xftpEncodeBatch1 . (,tToSend) =<< authTransmission thAuth False (Just pKey) (C.cbNonce $ bs corrId) tForAuth
+  xftpEncodeBatch1 . (,tToSend) =<< authTransmission thAuth False (Just pKey) (eitherToMaybe $ C.cbNonce $ bs corrId) tForAuth

 xftpEncodeTransmission :: ProtocolEncoding XFTPVersion XFTPErrorType c => THandleParams XFTPVersion p -> Transmission c -> Either TransportError ByteString
 xftpEncodeTransmission thParams t = xftpEncodeBatch1 (Nothing, encodeTransmission thParams t)
@@ -25,7 +25,6 @@ import Control.Monad.Reader
 import Control.Monad.Trans.Except
 import qualified Data.Aeson as J
 import Data.Bifunctor (first)
-import qualified Data.ByteString.Base64.URL as B64
 import Data.ByteString.Builder (Builder, byteString)
 import Data.ByteString.Char8 (ByteString)
 import qualified Data.ByteString.Char8 as B
@@ -65,7 +64,6 @@ import Simplex.Messaging.Encoding
 import Simplex.Messaging.Encoding.String
 import Simplex.Messaging.Protocol (BlockingInfo, CommandError (..), EntityId (..), RcvPublicAuthKey, RcvPublicDhKey, RecipientId, SignedTransmission, pattern NoEntity)
 import Simplex.Messaging.Server (controlPortAuth, dummyVerifyCmd, verifyCmdAuthorization)
-import Simplex.Messaging.Server.AddressStats (AddrStats, ServerAddrStats (..), addAddrCounter, addressStatsThread, incAddrCounter, printTopAddresses, withAddrStats)
 import Simplex.Messaging.Server.Control (CPClientRole (..))
 import Simplex.Messaging.Server.Expiration
 import Simplex.Messaging.Server.QueueStore (ServerEntityStatus (..))
@@ -102,8 +100,7 @@ data XFTPTransportRequest = XFTPTransportRequest
    request :: H.Request,
    sendResponse :: H.Response -> IO (),
    sniUsed :: SNICredentialUsed,
-    addCORS :: Bool,
-    clientAddrStats :: Maybe (AddrStats XFTPAddrCounter)
+    addCORS :: Bool
  }

 corsHeaders :: Bool -> [N.Header]
@@ -143,7 +140,6 @@ xftpServer cfg@XFTPServerConfig {xftpPort, transportConfig, inactiveClientExpira
        : expireFiles fileExpiration
        : serverStatsThread_ cfg
          <> prometheusMetricsThread_ cfg
-          <> addressStatsThread_ cfg
          <> controlPortThread_ cfg
    )
    `finally` stopServer
@@ -157,27 +153,20 @@ xftpServer cfg@XFTPServerConfig {xftpPort, transportConfig, inactiveClientExpira
        Left e -> putStrLn ("Server has no valid key: " <> show e) >> exitFailure
      env <- ask
      sessions <- liftIO TM.emptyIO
-      sessionAddrStats <- liftIO TM.emptyIO
-      stats_ <- asks addrStats
      let cleanup sessionId = atomically $ TM.delete sessionId sessions
-          withConnection sock sessionId handler =
-            withAddrStats (addrStatsMap <$> stats_) sock $ \case
-              Just s -> (atomically (TM.insert sessionId s sessionAddrStats) >> handler) `finally` atomically (TM.delete sessionId sessionAddrStats)
-              Nothing -> handler
          srvParams = if isJust httpCreds_ then defaultSupportedParamsHTTPS else defaultSupportedParams
      webCanonicalRoot_ <- liftIO $ mapM canonicalizePath (webStaticPath cfg)
-      liftIO . runHTTP2Server started xftpPort defaultHTTP2BufferSize srvParams srvCreds httpCreds_ transportConfig inactiveClientExpiration cleanup withConnection $ \sniUsed sessionId sessionALPN r sendResponse -> do
+      liftIO . runHTTP2Server started xftpPort defaultHTTP2BufferSize srvParams srvCreds httpCreds_ transportConfig inactiveClientExpiration cleanup $ \sniUsed sessionId sessionALPN r sendResponse -> do
        let addCORS' = sniUsed && addCORSHeaders transportConfig
        case H.requestMethod r of
          Just "OPTIONS" | addCORS' -> sendResponse $ H.responseNoBody N.ok200 corsPreflightHeaders
          Just "GET" | sniUsed -> forM_ webCanonicalRoot_ $ \root -> serveStaticPageH2 root r sendResponse
          _ -> do
            reqBody <- getHTTP2Body r xftpBlockSize
-            clientAddrStats <- TM.lookupIO sessionId sessionAddrStats
            let v = VersionXFTP 1
                thServerVRange = versionToRange v
                thParams0 = THandleParams {sessionId, blockSize = xftpBlockSize, thVersion = v, thServerVRange, thAuth = Nothing, implySessId = False, encryptBlock = Nothing, serviceAuth = False, serverInfo = Nothing}
-                req0 = XFTPTransportRequest {thParams = thParams0, request = r, reqBody, sendResponse, sniUsed, addCORS = addCORS', clientAddrStats}
+                req0 = XFTPTransportRequest {thParams = thParams0, request = r, reqBody, sendResponse, sniUsed, addCORS = addCORS'}
            flip runReaderT env $ case sessionALPN of
              Nothing -> processRequest req0
              Just alpn
@@ -340,30 +329,24 @@ xftpServer cfg@XFTPServerConfig {xftpPort, transportConfig, inactiveClientExpira
      [savePrometheusMetrics interval prometheusMetricsFile]
    prometheusMetricsThread_ _ = []

-    addressStatsThread_ :: XFTPServerConfig s -> [M s ()]
-    addressStatsThread_ XFTPServerConfig {addressStats = Just statsCfg} = [asks addrStats >>= mapM_ (liftIO . addressStatsThread statsCfg)]
-    addressStatsThread_ _ = []
-
    savePrometheusMetrics :: Int -> FilePath -> M s ()
    savePrometheusMetrics saveInterval metricsFile = do
      labelMyThread "savePrometheusMetrics"
      liftIO $ putStrLn $ "Prometheus metrics saved every " <> show saveInterval <> " seconds to " <> metricsFile
      ss <- asks serverStats
-      stats_ <- asks addrStats
      rtsOpts <- liftIO $ maybe ("set " <> rtsOptionsEnv) T.pack <$> lookupEnv (T.unpack rtsOptionsEnv)
      let interval = 1000000 * saveInterval
      liftIO $ forever $ do
        threadDelay interval
        ts <- getCurrentTime
-        sm <- getFileServerMetrics ss stats_ rtsOpts
+        sm <- getFileServerMetrics ss rtsOpts
        T.writeFile metricsFile $ xftpPrometheusMetrics sm ts

-    getFileServerMetrics :: FileServerStats -> Maybe (ServerAddrStats XFTPAddrCounter) -> T.Text -> IO FileServerMetrics
-    getFileServerMetrics ss stats_ rtsOptions = do
+    getFileServerMetrics :: FileServerStats -> T.Text -> IO FileServerMetrics
+    getFileServerMetrics ss rtsOptions = do
      d <- getFileServerStatsData ss
      let fd = periodStatDataCounts $ _filesDownloaded d
-      addressHistograms <- mapM (readIORef . addrHistograms) stats_
-      pure FileServerMetrics {statsData = d, filesDownloadedPeriods = fd, rtsOptions, addressHistograms}
+      pure FileServerMetrics {statsData = d, filesDownloadedPeriods = fd, rtsOptions}

    controlPortThread_ :: XFTPServerConfig s -> [M s ()]
    controlPortThread_ XFTPServerConfig {controlPort = Just port} = [runCPServer port]
@@ -418,10 +401,7 @@ xftpServer cfg@XFTPServerConfig {xftpPort, transportConfig, inactiveClientExpira
                  (fr, _) <- ExceptT $ liftIO $ getFile fs SFRecipient fileId
                  ExceptT $ blockServerFile fr info
                liftIO . hPutStrLn h $ either (\e -> "error: " <> show e) (\() -> "ok") r
-              CPAddresses name n_ -> withUserRole $ do
-                stats_ <- unliftIO u $ asks addrStats
-                printTopAddresses h (addrStatsMap <$> stats_) name n_
-              CPHelp -> hPutStrLn h "commands: stats-rts, delete, addresses, help, quit"
+              CPHelp -> hPutStrLn h "commands: stats-rts, delete, help, quit"
              CPQuit -> pure ()
              CPSkip -> pure ()
              where
@@ -440,23 +420,21 @@ data ServerFile = ServerFile
  }

 processRequest :: FileStoreClass s => XFTPTransportRequest -> M s ()
-processRequest XFTPTransportRequest {thParams, reqBody = body@HTTP2Body {bodyHead}, sendResponse, addCORS, clientAddrStats}
-  | B.length bodyHead /= xftpBlockSize = incAddrStats XACErrors >> sendXFTPResponse ("", NoEntity, FRErr BLOCK) Nothing
+processRequest XFTPTransportRequest {thParams, reqBody = body@HTTP2Body {bodyHead}, sendResponse, addCORS}
+  | B.length bodyHead /= xftpBlockSize = sendXFTPResponse ("", NoEntity, FRErr BLOCK) Nothing
  | otherwise =
      case xftpDecodeTServer thParams bodyHead of
-        Right (Right t@(_, _, (corrId, fId, cmd))) -> do
-          incAddrStats $ xftpCmdCounter cmd
+        Right (Right t@(_, _, (corrId, fId, _))) -> do
          let THandleParams {thAuth} = thParams
              ent = peerEntitlement =<< thAuth
          verifyXFTPTransmission thAuth t >>= \case
-            VRVerified req -> uncurry send =<< processXFTPRequest clientAddrStats ent body req
-            VRFailed e -> incAddrStats XACErrors >> send (FRErr e) Nothing
+            VRVerified req -> uncurry send =<< processXFTPRequest ent body req
+            VRFailed e -> send (FRErr e) Nothing
          where
            send resp = sendXFTPResponse (corrId, fId, resp)
-        Right (Left (corrId, fId, e)) -> incAddrStats XACErrors >> sendXFTPResponse (corrId, fId, FRErr e) Nothing
-        Left e -> incAddrStats XACErrors >> sendXFTPResponse ("", NoEntity, FRErr e) Nothing
+        Right (Left (corrId, fId, e)) -> sendXFTPResponse (corrId, fId, FRErr e) Nothing
+        Left e -> sendXFTPResponse ("", NoEntity, FRErr e) Nothing
  where
-    incAddrStats c = liftIO $ forM_ clientAddrStats (`incAddrCounter` c)
    sendXFTPResponse t' serverFile_ = do
      let t_ = xftpEncodeTransmission thParams t'
 #ifdef slow_servers
@@ -511,8 +489,8 @@ verifyXFTPTransmission thAuth (tAuth, authorized, (corrId, fId, cmd)) =
    -- TODO verify with DH authorization
    req `verifyWith` k = if verifyCmdAuthorization thAuth tAuth authorized corrId k then VRVerified req else VRFailed AUTH

-processXFTPRequest :: forall s. FileStoreClass s => Maybe (AddrStats XFTPAddrCounter) -> Maybe SessionEntitlement -> HTTP2Body -> XFTPRequest -> M s (FileResponse, Maybe ServerFile)
-processXFTPRequest addrStats_ ent HTTP2Body {bodyPart} = \case
+processXFTPRequest :: forall s. FileStoreClass s => Maybe SessionEntitlement -> HTTP2Body -> XFTPRequest -> M s (FileResponse, Maybe ServerFile)
+processXFTPRequest ent HTTP2Body {bodyPart} = \case
  XFTPReqNew file rks auth storageHours -> noFile =<< ifM allowNew (createFile file rks storageHours) (pure $ FRErr AUTH)
    where
      allowNew = do
@@ -530,10 +508,6 @@ processXFTPRequest addrStats_ ent HTTP2Body {bodyPart} = \case
  XFTPReqPing -> noFile FRPong
  where
    noFile resp = pure (resp, Nothing)
-    addAddrStats :: XFTPAddrCounter -> Int -> M s ()
-    addAddrStats c n = liftIO $ forM_ addrStats_ $ \s -> addAddrCounter s c n
-    kilobytes :: Word32 -> Int
-    kilobytes bytes = (fromIntegral bytes + 1023) `div` 1024
    createFile :: FileInfo -> NonEmpty RcvPublicAuthKey -> Maybe Word32 -> M s FileResponse
    createFile file rks storageHours = do
      st <- asks fileStore
@@ -557,7 +531,6 @@ processXFTPRequest addrStats_ ent HTTP2Body {bodyPart} = \case
        stats <- asks serverStats
        lift $ incFileStat filesCreated
        liftIO $ atomicModifyIORef'_ (fileRecipients stats) (+ length rks)
-        lift $ addAddrStats XACRecipients $ length rks
        let rIds = L.map (\(FileRecipient rId _) -> rId) rcps
        pure $ FRSndIds sId rIds (Just (GSTExpires (roundedSeconds fileExpiresAt)))
      pure $ either FRErr id r
@@ -593,7 +566,6 @@ processXFTPRequest addrStats_ ent HTTP2Body {bodyPart} = \case
        lift $ withFileLog $ \sl -> logAddRecipients sl sId rcps
        stats <- asks serverStats
        liftIO $ atomicModifyIORef'_ (fileRecipients stats) (+ length rks)
-        lift $ addAddrStats XACRecipients $ length rks
        let rIds = L.map (\(FileRecipient rId _) -> rId) rcps
        pure $ FRRcvIds rIds
      pure $ either FRErr id r
@@ -621,7 +593,7 @@ processXFTPRequest addrStats_ ent HTTP2Body {bodyPart} = \case
              \used -> let used' = used + fromIntegral size in if used' <= quota then (True, used') else (False, used)
          receive = do
            path <- asks $ filesPath . config
-            let fPath = path </> B.unpack (B64.encode $ unEntityId senderId)
+            let fPath = path </> serverFileName senderId
            receiveChunk (XFTPRcvChunkSpec fPath size digest) >>= \case
              Right () -> do
                stats <- asks serverStats
@@ -632,7 +604,6 @@ processXFTPRequest addrStats_ ent HTTP2Body {bodyPart} = \case
                    incFileStat filesUploaded
                    incFileStat filesCount
                    liftIO $ atomicModifyIORef'_ (filesSize stats) (+ fromIntegral size)
-                    addAddrStats XACUploadKb $ kilobytes size
                    pure FROk
                  Left _e -> do
                    us <- asks usedStorage
@@ -662,7 +633,6 @@ processXFTPRequest addrStats_ ent HTTP2Body {bodyPart} = \case
                  stats <- asks serverStats
                  incFileStat fileDownloads
                  liftIO $ updatePeriodStats (filesDownloaded stats) senderId
-                  addAddrStats XACDownloadKb $ kilobytes size
                  pure (FRFile sDhKey cbNonce, Just ServerFile {filePath = path, fileSize = size, sbState})
                _ -> pure (FRErr INTERNAL, Nothing)
        _ -> pure (FRErr NO_FILE, Nothing)
@@ -7,18 +7,15 @@ module Simplex.FileTransfer.Server.Control
 where

 import qualified Data.Attoparsec.ByteString.Char8 as A
-import Data.Text (Text)
 import Simplex.FileTransfer.Protocol (XFTPFileId)
 import Simplex.Messaging.Encoding.String
 import Simplex.Messaging.Protocol (BasicAuth, BlockingInfo)
-import Simplex.Messaging.Server.AddressStats (addressesArgs, addressesArgsP)

 data ControlProtocol
  = CPAuth BasicAuth
  | CPStatsRTS
  | CPDelete XFTPFileId
  | CPBlock XFTPFileId BlockingInfo
-  | CPAddresses Text (Maybe Int)
  | CPHelp
  | CPQuit
  | CPSkip
@@ -29,7 +26,6 @@ instance StrEncoding ControlProtocol where
    CPStatsRTS -> "stats-rts"
    CPDelete fId -> strEncode (Str "delete", fId)
    CPBlock fId info -> strEncode (Str "block", fId, info)
-    CPAddresses name n_ -> "addresses " <> addressesArgs name n_
    CPHelp -> "help"
    CPQuit -> "quit"
    CPSkip -> ""
@@ -39,7 +35,6 @@ instance StrEncoding ControlProtocol where
      "stats-rts" -> pure CPStatsRTS
      "delete" -> CPDelete <$> _strP
      "block" -> CPBlock <$> _strP <*> _strP
-      "addresses" -> uncurry CPAddresses <$> addressesArgsP
      "help" -> pure CPHelp
      "quit" -> pure CPQuit
      "" -> pure CPSkip
@@ -16,8 +16,6 @@ module Simplex.FileTransfer.Server.Env
    XFTPStoreConfig (..),
    XFTPEnv (..),
    XFTPRequest (..),
-    XFTPAddrCounter (..),
-    xftpCmdCounter,
    XFTPStoreType,
    FileStore (..),
    AFStoreType (..),
@@ -47,7 +45,7 @@ import Data.Word (Word16, Word32)
 import Data.X509.Validation (Fingerprint (..))
 import Network.Socket
 import qualified Network.TLS as T
-import Simplex.FileTransfer.Protocol (FileCmd (..), FileCommand (..), FileInfo (..), XFTPFileId)
+import Simplex.FileTransfer.Protocol (FileCmd, FileInfo (..), XFTPFileId)
 import Simplex.FileTransfer.Server.Stats
 import Data.Either (fromRight)
 import Data.Ini (Ini, lookupValue)
@@ -69,7 +67,6 @@ import Simplex.FileTransfer.Transport (VersionRangeXFTP)
 import qualified Simplex.Messaging.Crypto as C
 import Simplex.Messaging.Crypto.BBS (BBSPublicKey)
 import Simplex.Messaging.Protocol (BasicAuth, RcvPublicAuthKey)
-import Simplex.Messaging.Server.AddressStats (AddrCounter (..), AddressStatsConfig, ServerAddrStats, countBounds, kilobyteBounds, newServerAddrStats)
 import Simplex.Messaging.Server.Expiration
 import Simplex.Messaging.Server.Information (ServerPublicInfo)
 import Simplex.Messaging.Transport (EntitlementConfig (..))
@@ -118,7 +115,6 @@ data XFTPServerConfig s = XFTPServerConfig
    serverStatsBackupFile :: Maybe FilePath,
    prometheusInterval :: Maybe Int,
    prometheusMetricsFile :: FilePath,
-    addressStats :: Maybe AddressStatsConfig,
    transportConfig :: TransportServerConfig,
    responseDelay :: Int,
    webStaticPath :: Maybe FilePath
@@ -140,55 +136,9 @@ data XFTPEnv s = XFTPEnv
    serverIdentity :: C.KeyHash,
    tlsServerCreds :: T.Credential,
    httpServerCreds :: Maybe T.Credential,
-    serverStats :: FileServerStats,
-    addrStats :: Maybe (ServerAddrStats XFTPAddrCounter)
+    serverStats :: FileServerStats
  }

-data XFTPAddrCounter
-  = XACConnections
-  | XACErrors
-  | XACFNew
-  | XACFAdd
-  | XACFPut
-  | XACFDel
-  | XACFGet
-  | XACFAck
-  | XACPing
-  | XACUploadKb
-  | XACDownloadKb
-  | XACRecipients
-  deriving (Eq, Ord, Enum, Bounded, Show)
-
-instance AddrCounter XFTPAddrCounter where
-  counterName = \case
-    XACConnections -> "connections"
-    XACErrors -> "errors"
-    XACFNew -> "FNEW"
-    XACFAdd -> "FADD"
-    XACFPut -> "FPUT"
-    XACFDel -> "FDEL"
-    XACFGet -> "FGET"
-    XACFAck -> "FACK"
-    XACPing -> "PING"
-    XACUploadKb -> "upload_kb"
-    XACDownloadKb -> "download_kb"
-    XACRecipients -> "recipients"
-  counterBounds = \case
-    XACUploadKb -> kilobyteBounds
-    XACDownloadKb -> kilobyteBounds
-    _ -> countBounds
-  connectionsCounter = XACConnections
-
-xftpCmdCounter :: FileCmd -> XFTPAddrCounter
-xftpCmdCounter (FileCmd _ cmd) = case cmd of
-  FNEW {} -> XACFNew
-  FADD _ -> XACFAdd
-  FPUT -> XACFPut
-  FDEL -> XACFDel
-  FGET _ -> XACFGet
-  FACK -> XACFAck
-  PING -> XACPing
-
 fileStore :: XFTPEnv s -> s
 fileStore = fromFileStore . store
 {-# INLINE fileStore #-}
@@ -232,7 +182,7 @@ defaultFileExpiration =
    }

 newXFTPServerEnv :: FileStoreClass s => XFTPServerConfig s -> IO (XFTPEnv s)
-newXFTPServerEnv config@XFTPServerConfig {serverStoreCfg, fileSizeQuota, fileExpiration, fileStorageEntitlements, xftpCredentials, httpCredentials, addressStats} = do
+newXFTPServerEnv config@XFTPServerConfig {serverStoreCfg, fileSizeQuota, fileExpiration, fileStorageEntitlements, xftpCredentials, httpCredentials} = do
  let defaultMax = ttl fileExpiration
      belowDefault = M.filter ((< defaultMax) . storageTime) fileStorageEntitlements
  unless (M.null belowDefault) $ do
@@ -260,8 +210,7 @@ newXFTPServerEnv config@XFTPServerConfig {serverStoreCfg, fileSizeQuota, fileExp
  httpServerCreds <- mapM loadServerCredential httpCredentials
  Fingerprint fp <- loadFingerprint xftpCredentials
  serverStats <- newFileServerStats =<< getCurrentTime
-  addrStats <- mapM (const newServerAddrStats) addressStats
-  pure XFTPEnv {config, store, usedStorage, storeLog, random, tlsServerCreds, httpServerCreds, serverIdentity = C.KeyHash fp, serverStats, addrStats}
+  pure XFTPEnv {config, store, usedStorage, storeLog, random, tlsServerCreds, httpServerCreds, serverIdentity = C.KeyHash fp, serverStats}

 data XFTPRequest
  = XFTPReqNew FileInfo (NonEmpty RcvPublicAuthKey) (Maybe BasicAuth) (Maybe Word32)
@@ -204,8 +204,6 @@ xftpServerCLI_ generateSite serveStaticFiles cfgPath logPath = do
               \disconnect = off\n"
            <> ("# ttl = " <> tshow (ttl defaultInactiveClientExpiration) <> "\n")
            <> ("# check_interval = " <> tshow (checkInterval defaultInactiveClientExpiration) <> "\n")
-            <> "\n"
-            <> addressStatsIniContent
            <> "\n\
               \[WEB]\n\
               \# Set path to generate static mini-site for server information\n"
@@ -327,7 +325,6 @@ xftpServerCLI_ generateSite serveStaticFiles cfgPath logPath = do
              serverStatsBackupFile = logStats $> combine logPath "file-server-stats.log",
              prometheusInterval = eitherToMaybe (lookupValue "STORE_LOG" "prometheus_interval" ini) >>= readMaybe . T.unpack,
              prometheusMetricsFile = combine logPath "xftp-server-metrics.txt",
-              addressStats = iniAddressStats ini,
              transportConfig =
                let cfg =
                      mkTransportServerConfig
@@ -11,15 +11,12 @@ module Simplex.FileTransfer.Server.Prometheus
  ) where

 import Data.Int (Int64)
-import Data.Map.Strict (Map)
 import Data.Text (Text)
 import qualified Data.Text as T
 import Data.Time.Clock (UTCTime (..), diffUTCTime)
 import Data.Time.Clock.System (systemEpochDay)
 import Data.Time.Format.ISO8601 (iso8601Show)
-import Simplex.FileTransfer.Server.Env (XFTPAddrCounter)
 import Simplex.FileTransfer.Server.Stats
-import Simplex.Messaging.Server.AddressStats (AddrHistogram, addrHistogramMetrics)
 import Simplex.Messaging.Server.Stats (PeriodStatCounts (..))
 import Simplex.Messaging.Transport (simplexMQVersion)
 import Simplex.Messaging.Util (tshow)
@@ -27,8 +24,7 @@ import Simplex.Messaging.Util (tshow)
 data FileServerMetrics = FileServerMetrics
  { statsData :: FileServerStatsData,
    filesDownloadedPeriods :: PeriodStatCounts,
-    rtsOptions :: Text,
-    addressHistograms :: Maybe (Map XFTPAddrCounter AddrHistogram)
+    rtsOptions :: Text
  }

 rtsOptionsEnv :: Text
@@ -37,9 +33,9 @@ rtsOptionsEnv = "XFTP_RTS_OPTIONS"
 {-# FOURMOLU_DISABLE\n#-}
 xftpPrometheusMetrics :: FileServerMetrics -> UTCTime -> Text
 xftpPrometheusMetrics sm ts =
-  time <> files <> clientAddresses <> info
+  time <> files <> info
  where
-    FileServerMetrics {statsData, filesDownloadedPeriods, rtsOptions, addressHistograms} = sm
+    FileServerMetrics {statsData, filesDownloadedPeriods, rtsOptions} = sm
    FileServerStatsData
      { _fromTime,
        _filesCreated,
@@ -126,7 +122,6 @@ xftpPrometheusMetrics sm ts =
      \simplex_xftp_files_count_monthly " <> mstr (monthCount filesDownloadedPeriods) <> "\n\
      \# filesDownloaded.monthCount\n\
      \\n"
-    clientAddresses = maybe "" (addrHistogramMetrics "simplex_xftp" tsEpoch) addressHistograms
    info =
      "# Info\n\
      \# ----\n\
@@ -17,6 +17,7 @@ module Simplex.FileTransfer.Server.StoreLog
    logDeleteFile,
    logBlockFile,
    logAckFile,
+    serverFileName,
  )
 where

@@ -24,6 +25,7 @@ import Control.Applicative (optional, (<|>))
 import Control.Concurrent.STM
 import Control.Monad.Except
 import qualified Data.Attoparsec.ByteString.Char8 as A
+import qualified Data.ByteString.Base64.URL as B64
 import qualified Data.ByteString.Char8 as B
 import qualified Data.ByteString.Lazy.Char8 as LB
 import Data.Composition ((.:), (.::.))
@@ -35,10 +37,11 @@ import Simplex.FileTransfer.Protocol (FileInfo (..))
 import Simplex.FileTransfer.Server.Store
 import Simplex.FileTransfer.Transport (XFTPErrorType (..))
 import Simplex.Messaging.Encoding.String
-import Simplex.Messaging.Protocol (BlockingInfo, RcvPublicAuthKey, RecipientId, SenderId)
+import Simplex.Messaging.Protocol (BlockingInfo, EntityId (..), RcvPublicAuthKey, RecipientId, SenderId)
 import Simplex.Messaging.Server.QueueStore (ServerEntityStatus (..))
 import Simplex.Messaging.Server.StoreLog
 import Simplex.Messaging.Util (bshow)
+import System.FilePath (takeFileName)
 import System.IO

 data FileStoreLogRecord
@@ -99,6 +102,9 @@ logBlockFile s fId = logFileStoreRecord s . BlockFile fId
 logAckFile :: StoreLog 'WriteMode -> RecipientId -> IO ()
 logAckFile s = logFileStoreRecord s . AckFile

+serverFileName :: SenderId -> FilePath
+serverFileName = B.unpack . B64.encode . unEntityId
+
 readWriteFileStore :: FilePath -> STMFileStore -> IO (StoreLog 'WriteMode)
 readWriteFileStore = readWriteStoreLog readFileStore writeFileStore

@@ -115,7 +121,9 @@ readFileStore f st = mapM_ (addFileLogRecord . LB.toStrict) . LB.lines =<< LB.re
      AddFile sId file createdAt expiresAt status
        | size file > 0 -> addFile st sId file createdAt expiresAt status
        | otherwise -> pure $ Left SIZE
-      PutFile qId path -> setFilePath st qId path
+      PutFile qId path
+        | takeFileName path == serverFileName qId -> setFilePath st qId path
+        | otherwise -> pure $ Left AUTH
      AddRecipients sId rcps -> runExceptT $ addRecipients sId rcps
      DeleteFile sId -> deleteFile st sId
      BlockFile sId info -> blockFile st sId info True
@@ -108,8 +108,8 @@ supportedFileServerVRange :: VersionRangeXFTP
 supportedFileServerVRange = mkVersionRange initialXFTPVersion currentXFTPVersion

 -- XFTP protocol does not use this handshake method
-xftpClientHandshakeStub :: c 'TClient -> Maybe C.KeyPairX25519 -> C.KeyHash -> VersionRangeXFTP -> Bool -> Maybe (ServiceCredentials, C.KeyPairEd25519) -> (SessionId -> IO (Maybe EntitlementProof)) -> ExceptT TransportError IO (THandle XFTPVersion c 'TClient)
-xftpClientHandshakeStub _c _ks _keyHash _xftpVRange _proxyServer _serviceKeys _mkEntitlementProof = throwE TEVersion
+xftpClientHandshakeStub :: c 'TClient -> Maybe C.KeyPairX25519 -> C.KeyHash -> VersionRangeXFTP -> Bool -> Maybe (ServiceCredentials, C.KeyPairEd25519) -> ExceptT TransportError IO (THandle XFTPVersion c 'TClient)
+xftpClientHandshakeStub _c _ks _keyHash _xftpVRange _proxyServer _serviceKeys = throwE TEVersion

 alpnSupportedXFTPhandshakes :: [ALPN]
 alpnSupportedXFTPhandshakes = [xftpALPNv1]
@@ -41,7 +41,7 @@ module Simplex.Messaging.Agent.Client
    reconnectServerClients,
    reconnectSMPServer,
    closeXFTPServerClient,
-    closeUserClients,
+    closeUserXFTPClients,
    runSMPServerTest,
    runXFTPServerTest,
    runNTFServerTest,
@@ -312,7 +312,7 @@ import Simplex.Messaging.Session
 import Simplex.Messaging.SystemTime
 import Simplex.Messaging.TMap (TMap)
 import qualified Simplex.Messaging.TMap as TM
-import Simplex.Messaging.Transport (HandshakeError (..), SMPServiceRole (..), SMPVersion, ServiceCredentials (..), SessionId, THClientService' (..), THandleAuth (..), THandleParams (sessionId, thAuth, thVersion, serverInfo), TransportError (..), TransportPeer (..), shortLinksSMPVersion, newNtfCredsSMPVersion)
+import Simplex.Messaging.Transport (HandshakeError (..), SMPServiceRole (..), SMPVersion, ServiceCredentials (..), SessionId, THClientService' (..), THandleAuth (..), THandleParams (sessionId, thAuth, thVersion, serverInfo), TransportError (..), newNtfCredsSMPVersion)
 import Simplex.Messaging.Transport.Client (TransportHost (..))
 import Simplex.Messaging.Transport.Credentials
 import Simplex.Messaging.Util
@@ -760,10 +760,9 @@ smpConnectClient c@AgentClient {smpClients, msgQ, proxySessTs, presetDomains} nm
    connectClient :: SMPClientVar -> AM SMPConnectedClient
    connectClient v' = do
      cfg <- lift $ getClientConfig c smpCfg
-      keys <- asks $ entitlementKeys . config
      g <- asks random
      service <- getServiceCredentials c userId srv
-      let cfg' = cfg {serviceCredentials = fst <$> service, mkEntitlementProof = userEntitlementProof c keys userId $ knownUserServer (smpServers c) userId srv}
+      let cfg' = cfg {serviceCredentials = fst <$> service}
      env <- ask
      smp <- liftError (protocolClientError SMP $ B.unpack $ strEncode srv) $ do
        ts <- readTVarIO proxySessTs
@@ -864,7 +863,7 @@ notifySub c = notifySub' c ""
 {-# INLINE notifySub #-}

 getNtfServerClient :: AgentClient -> NetworkRequestMode -> NtfTransportSession -> AM NtfClient
-getNtfServerClient c@AgentClient {active, ntfClients, workerSeq, proxySessTs, presetDomains} nm tSess@(userId, srv, _) = do
+getNtfServerClient c@AgentClient {active, ntfClients, workerSeq, proxySessTs, presetDomains} nm tSess@(_, srv, _) = do
  unlessM (readTVarIO active) $ throwE INACTIVE
  ts <- liftIO getCurrentTime
  withGetSessVar workerSeq tSess ntfClients ts (newProtocolClient c tSess ntfClients connectClient) (waitForProtocolClient c nm tSess ntfClients)
@@ -872,12 +871,10 @@ getNtfServerClient c@AgentClient {active, ntfClients, workerSeq, proxySessTs, pr
    connectClient :: NtfClientVar -> AM NtfClient
    connectClient v = do
      cfg <- lift $ getClientConfig c ntfCfg
-      keys <- asks $ entitlementKeys . config
      g <- asks random
      ts <- readTVarIO proxySessTs
-      let cfg' = cfg {mkEntitlementProof = userEntitlementProof c keys userId $ knownNtfServer c srv}
      liftError' (protocolClientError NTF $ B.unpack $ strEncode srv) $
-        getProtocolClient g nm tSess cfg' presetDomains Nothing ts $
+        getProtocolClient g nm tSess cfg presetDomains Nothing ts $
          clientDisconnected v

    clientDisconnected :: NtfClientVar -> NtfClient -> IO ()
@@ -887,7 +884,7 @@ getNtfServerClient c@AgentClient {active, ntfClients, workerSeq, proxySessTs, pr
      logInfo . decodeUtf8 $ "Agent disconnected from " <> showServer srv

 getXFTPServerClient :: AgentClient -> XFTPTransportSession -> AM XFTPClient
-getXFTPServerClient c@AgentClient {active, xftpClients, workerSeq, proxySessTs, presetDomains} tSess@(userId, srv, _) = do
+getXFTPServerClient c@AgentClient {active, xftpClients, userEntitlements, workerSeq, proxySessTs, presetDomains} tSess@(userId, srv, _) = do
  unlessM (readTVarIO active) $ throwE INACTIVE
  ts <- liftIO getCurrentTime
  withGetSessVar workerSeq tSess xftpClients ts (newProtocolClient c tSess xftpClients connectClient) (waitForProtocolClient c NRMBackground tSess xftpClients)
@@ -899,38 +896,30 @@ getXFTPServerClient c@AgentClient {active, xftpClients, workerSeq, proxySessTs,
      xftpNetworkConfig <- getNetworkConfig c
      ts <- readTVarIO proxySessTs
      liftError' (protocolClientError XFTP $ B.unpack $ strEncode srv) $
-        X.getXFTPClient tSess cfg {xftpNetworkConfig} presetDomains ts (userEntitlementProof c keys userId $ knownUserServer (xftpServers c) userId srv) $
+        X.getXFTPClient tSess cfg {xftpNetworkConfig} presetDomains ts (mkEntitlementProof keys) $
          clientDisconnected v

+    mkEntitlementProof :: Map Word16 BBSPublicKey -> SessionId -> IO (Maybe EntitlementProof)
+    mkEntitlementProof keys sessId =
+      ifM knownServer proof (pure Nothing)
+      where
+        -- the entitlement is presented only to the servers of this user, matched by key hash that TLS pins,
+        -- so a file description of the sender cannot direct it to another server
+        knownServer = maybe False (any (sameKeyHash . snd) . storageSrvs) <$> TM.lookupIO userId (xftpServers c)
+        sameKeyHash (ProtoServerWithAuth srv' _) = srvKeyHash srv' == srvKeyHash srv
+        srvKeyHash (ProtocolServer _ _ _ kh) = kh
+        proof =
+          TM.lookupIO userId userEntitlements $>>= \cred ->
+            generateEntitlementProof keys cred (BBSPresHeader sessId) >>= \case
+              Right p -> pure $ Just p
+              Left e -> Nothing <$ logError ("entitlement proof error: " <> tshow e)
+
    clientDisconnected :: XFTPClientVar -> XFTPClient -> IO ()
    clientDisconnected v client = do
      atomically $ removeSessVar v tSess xftpClients
      atomically $ writeTBQueue (subQ c) ("", "", AEvt SAENone $ hostEvent DISCONNECT client)
      logInfo . decodeUtf8 $ "Agent disconnected from " <> showServer srv

-userEntitlementProof :: AgentClient -> Map Word16 BBSPublicKey -> UserId -> IO Bool -> SessionId -> IO (Maybe EntitlementProof)
-userEntitlementProof AgentClient {userEntitlements} keys userId knownServer sessId =
-  ifM knownServer proof (pure Nothing)
-  where
-    proof =
-      TM.lookupIO userId userEntitlements $>>= \cred ->
-        generateEntitlementProof keys cred (BBSPresHeader sessId) >>= \case
-          Right p -> pure $ Just p
-          Left e -> Nothing <$ logError ("entitlement proof error: " <> tshow e)
-
-- the entitlement is presented only to the servers of this user, matched by key hash that TLS pins,
-- so a server address received from another party cannot direct it to another server
-knownUserServer :: TMap UserId (UserServers p) -> UserId -> ProtocolServer p -> IO Bool
-knownUserServer servers userId srv = maybe False (any sameSrvKeyHash . storageSrvs) <$> TM.lookupIO userId servers
-  where
-    sameSrvKeyHash (_, ProtoServerWithAuth srv' _) = sameKeyHash srv srv'
-
-knownNtfServer :: AgentClient -> NtfServer -> IO Bool
-knownNtfServer c srv = any (sameKeyHash srv) <$> readTVarIO (ntfServers c)
-
-sameKeyHash :: ProtocolServer p -> ProtocolServer p -> Bool
-sameKeyHash ProtocolServer {keyHash} ProtocolServer {keyHash = kh} = keyHash == kh
-
 waitForProtocolClient ::
  (ProtocolTypeI (ProtoType msg), ProtocolServerClient v err msg) =>
  AgentClient ->
@@ -1070,15 +1059,9 @@ reconnectSMPServer c userId srv = do
      | userId == userId' && srv == srv' = (v :)
      | otherwise = id

-closeUserClients :: AgentClient -> UserId -> IO ()
-closeUserClients c userId = do
-  closeUserSessions c userId smpClients
-  closeUserSessions c userId ntfClients
-  closeUserSessions c userId xftpClients
-
-closeUserSessions :: ProtocolServerClient v err msg => AgentClient -> UserId -> (AgentClient -> TMap (TransportSession msg) (ClientVar msg)) -> IO ()
-closeUserSessions c userId clientsSel = do
-  vs <- atomically $ stateTVar (clientsSel c) $ \cs ->
+closeUserXFTPClients :: AgentClient -> UserId -> IO ()
+closeUserXFTPClients c userId = do
+  vs <- atomically $ stateTVar (xftpClients c) $ \cs ->
    let (userCs, cs') = M.partitionWithKey (\(userId', _, _) _ -> userId == userId') cs
     in (M.elems userCs, cs')
  mapM_ (forkIO . closeClient_ c) vs
@@ -1278,9 +1261,12 @@ sendOrProxySMPCommand c nm userId destSrv@ProtocolServer {host = destHosts} conn
          Left e -> throwE e

 ipAddressProtected :: NetworkConfig -> ProtocolServer p -> Bool
-ipAddressProtected NetworkConfig {socksProxy, hostMode} (ProtocolServer _ hosts _ _) = do
-  isJust socksProxy || (hostMode == HMOnion && any isOnionHost hosts)
+ipAddressProtected NetworkConfig {socksProxy, socksMode, hostMode} (ProtocolServer _ hosts _ _)
+  | isJust socksProxy = socksMode == SMAlways || if hostMode == HMPublic then allOnion else anyOnion
+  | otherwise = hostMode == HMOnion && anyOnion
  where
+    anyOnion = any isOnionHost hosts
+    allOnion = all isOnionHost hosts
    isOnionHost = \case THOnionHost _ -> True; _ -> False

 withNtfClient :: AgentClient -> NetworkRequestMode -> NtfServer -> EntityId -> ByteString -> (NtfClient -> ExceptT NtfClientError IO a) -> AM a
@@ -1513,7 +1499,7 @@ newRcvQueue_ c nm userId connId (ProtoServerWithAuth srv auth) vRange cqrd enabl
  let sessServiceId = (\THClientService {serviceId = sId} -> sId) <$> (clientService =<< thAuth thParams')
  when (isJust serviceId && serviceId /= sessServiceId) $ logError "incorrect service ID in NEW response"
  liftIO . logServer "<--" c srv NoEntity $ B.unwords ["IDS", logSecret rcvId, logSecret sndId]
-  shortLink <- mkShortLinkCreds thParams' qik
+  shortLink <- mkShortLinkCreds qik
  let rq =
        RcvQueue
          { userId,
@@ -1554,8 +1540,8 @@ newRcvQueue_ c nm userId connId (ProtoServerWithAuth srv auth) vRange cqrd enabl
      (Just ((ntfPublicKey, ntfPrivateKey), dhpk), Just (ServerNtfCreds notifierId dhk')) ->
        Just ClientNtfCreds {ntfPublicKey, ntfPrivateKey, notifierId, rcvNtfDhSecret = C.dh' dhk' dhpk}
      _ -> Nothing
-    mkShortLinkCreds :: THandleParams SMPVersion 'TClient -> QueueIdsKeys -> AM (Maybe ShortLinkCreds)
-    mkShortLinkCreds thParams' QIK {sndId, queueMode, linkId} = case (cqrd, queueMode) of
+    mkShortLinkCreds :: QueueIdsKeys -> AM (Maybe ShortLinkCreds)
+    mkShortLinkCreds QIK {sndId, queueMode, linkId} = case (cqrd, queueMode) of
      (CQRMessaging ld, Just QMMessaging) ->
        withLinkData ld $ \lnkId CQRData {linkKey, privSigKey, srvReq = (sndId', d)} ->
          if sndId == sndId'
@@ -1569,11 +1555,9 @@ newRcvQueue_ c nm userId connId (ProtoServerWithAuth srv auth) vRange cqrd enabl
      (_, Nothing) -> newErr "unexpected link ID"
      _ -> newErr "unexpected queue mode"
      where
-        v = thVersion thParams'
        withLinkData :: Maybe d -> (SMP.LinkId -> d -> AM (Maybe ShortLinkCreds)) -> AM (Maybe ShortLinkCreds)
        withLinkData ld_ mkLink = case (ld_, linkId) of
          (Just ld, Just lnkId) -> mkLink lnkId ld
-          (Just _, Nothing) | v < shortLinksSMPVersion -> pure Nothing
          (Nothing, Nothing) -> pure Nothing
          _ -> newErr "unexpected or absent link ID"
        newErr :: String -> AM (Maybe ShortLinkCreds)
@@ -1998,7 +1982,7 @@ decryptSMPMessage :: RcvQueue -> SMP.RcvMessage -> AM SMP.ClientRcvMsgBody
 decryptSMPMessage rq SMP.RcvMessage {msgId, msgBody = SMP.EncRcvMsgBody body} =
  liftEither $ parse SMP.clientRcvMsgBodyP (AGENT $ A_MESSAGE "decrypt message") =<< decrypt body
  where
-    decrypt = agentCbDecrypt (rcvDhSecret rq) (C.cbNonce msgId)
+    decrypt = agentCbDecrypt (rcvDhSecret rq) msgId

 secureQueue :: AgentClient -> NetworkRequestMode -> RcvQueue -> SndPublicAuthKey -> AM ()
 secureQueue c nm rq@RcvQueue {rcvId, rcvPrivateKey} senderKey =
@@ -2096,9 +2080,9 @@ disableQueuesNtfs c = sendTSessionBatches "NDEL" (mkSMPTSession . snd) disableQu
    queueCreds :: DisableQueueNtfReq -> (SMP.RecipientId, SMP.RcvPrivateAuthKey)
    queueCreds (_, RcvQueue {rcvPrivateKey, rcvId}) = (rcvId, rcvPrivateKey)

-sendAck :: AgentClient -> RcvQueue -> MsgId -> AM ()
+sendAck :: AgentClient -> RcvQueue -> MsgId -> AM QueueDrained
 sendAck c rq@RcvQueue {rcvId, rcvPrivateKey} msgId =
-  withSMPClient c NRMBackground rq ("ACK:" <> logSecret' msgId) $ \smp ->
+  withSMPClient c NRMBackground rq ("ACK:" <> logSecret' (SMP.unMsgId msgId)) $ \smp ->
    ackSMPMessage smp rcvPrivateKey rcvId msgId

 hasGetLock :: SomeRcvQueue q => AgentClient -> q -> IO Bool
@@ -2293,7 +2277,7 @@ agentCbEncryptOnce clientVersion dhRcvPubKey msg = do

 -- | NaCl crypto-box decrypt - both for messages received from the server
 -- and per-queue E2E encrypted messages from the sender that were inside.
-agentCbDecrypt :: C.DhSecretX25519 -> C.CbNonce -> ByteString -> Either AgentErrorType ByteString
+agentCbDecrypt :: C.CbNonceI n => C.DhSecretX25519 -> n -> ByteString -> Either AgentErrorType ByteString
 agentCbDecrypt dhSecret nonce msg =
  first cryptoError $
    C.cbDecrypt dhSecret nonce msg
@@ -79,6 +79,7 @@ module Simplex.Messaging.Agent.Protocol
    SMPConfirmation (..),
    AgentMsgEnvelope (..),
    AgentMessage (..),
+    RatchetInfo (..),
    RequestSignature (..),
    AgentMessageType (..),
    APrivHeader (..),
@@ -245,7 +246,6 @@ import Simplex.Messaging.Crypto.Ratchet
    RcvE2ERatchetParams,
    RcvE2ERatchetParamsUri,
    SndE2ERatchetParams,
-    RcvE2EPrivRatchetParams,
    pattern PQSupportOff,
    pattern PQSupportOn,
  )
@@ -611,6 +611,7 @@ data RcvSwitchStatus
  | RSSendingQADD
  | RSSendingQUSE
  | RSReceivedMessage
+  | RSReceivedQEND
  deriving (Eq, Show)

 instance StrEncoding RcvSwitchStatus where
@@ -619,12 +620,14 @@ instance StrEncoding RcvSwitchStatus where
    RSSendingQADD -> "sending_qadd"
    RSSendingQUSE -> "sending_quse"
    RSReceivedMessage -> "received_message"
+    RSReceivedQEND -> "received_qend"
  strP =
    A.takeTill (== ' ') >>= \case
      "switch_started" -> pure RSSwitchStarted
      "sending_qadd" -> pure RSSendingQADD
      "sending_quse" -> pure RSSendingQUSE
      "received_message" -> pure RSReceivedMessage
+      "received_qend" -> pure RSReceivedQEND
      _ -> fail "bad RcvSwitchStatus"

 instance ToField RcvSwitchStatus where toField = toField . decodeLatin1 . strEncode
@@ -928,7 +931,7 @@ data AgentMessage
  | -- AgentConnInfoReply is used by accepting party in duplexHandshake mode (v2), allowing to include reply queue(s) in the initial confirmation.
    -- It made removed REPLY message unnecessary.
    AgentConnInfoReply (NonEmpty SMPQueueInfo) ConnInfo
-  | AgentRatchetInfo ByteString
+  | AgentRatchetInfo RatchetInfo
  | AgentMessage APrivHeader AMessage
  | AgentServiceRequest (NonEmpty SMPQueueInfo) (Maybe RequestSignature) MsgBody
  | AgentServiceResponse MsgBody
@@ -939,7 +942,7 @@ instance Encoding AgentMessage where
  smpEncode = \case
    AgentConnInfo cInfo -> smpEncode ('I', Tail cInfo)
    AgentConnInfoReply smpQueues cInfo -> smpEncode ('D', smpQueues, Tail cInfo) -- 'D' stands for "duplex"
-    AgentRatchetInfo info -> smpEncode ('R', Tail info)
+    AgentRatchetInfo info -> smpEncode ('R', info)
    AgentMessage hdr aMsg -> smpEncode ('M', hdr, aMsg)
    AgentServiceRequest qs sig_ body -> smpEncode ('A', qs, sig_, Tail body)
    AgentServiceResponse body -> smpEncode ('P', Tail body)
@@ -948,13 +951,23 @@ instance Encoding AgentMessage where
    smpP >>= \case
      'I' -> AgentConnInfo . unTail <$> smpP
      'D' -> AgentConnInfoReply <$> smpP <*> (unTail <$> smpP)
-      'R' -> AgentRatchetInfo . unTail <$> smpP
+      'R' -> AgentRatchetInfo <$> smpP
      'M' -> AgentMessage <$> smpP <*> smpP
      'A' -> AgentServiceRequest <$> smpP <*> smpP <*> (unTail <$> smpP)
      'P' -> AgentServiceResponse . unTail <$> smpP
      'J' -> AgentRejection . unTail <$> smpP
      _ -> fail "bad AgentMessage"

+data RatchetInfo = RatchetInfo {answeredKeyHash :: Maybe ByteString}
+  deriving (Eq, Show)
+
+instance Encoding RatchetInfo where
+  smpEncode RatchetInfo {answeredKeyHash} = smpEncode answeredKeyHash
+  smpP = do
+    answeredKeyHash <- smpP <|> pure Nothing
+    _ <- A.takeByteString
+    pure RatchetInfo {answeredKeyHash}
+
 -- internal type for storing message type in the database
 data AgentMessageType
  = AM_CONN_INFO
@@ -1613,7 +1626,7 @@ newtype LinkKey = LinkKey ByteString -- sha3-256(fixed_data)
 instance ToField LinkKey where toField (LinkKey s) = toField $ Binary s

 -- | Parameters for creating a connection with a prepared link.
-data PreparedLinkParams = PreparedLinkParams
+data PreparedLinkParams k = PreparedLinkParams
  { -- | Correlation ID / determines sender ID
    plpNonce :: C.CbNonce,
    -- | Queue E2EE DH key pair
@@ -1628,8 +1641,8 @@ data PreparedLinkParams = PreparedLinkParams
    plpSrvWithAuth :: SMPServerWithAuth,
    -- | Initial PQ keys
    plpInitKeys :: InitialKeys,
-    -- | Contact address double ratchet keys
-    plpAddressKeys :: Maybe (RatchetKeyId, RcvE2EPrivRatchetParams 'C.X448)
+    -- | Contact address double ratchet keys or invitation X3DH keys
+    plpRatchetKeys :: k
  }

 instance ConnectionModeI c => ToField (ConnectionLink c) where toField = toField . Binary . strEncode
@@ -219,6 +219,7 @@ canAbortRcvSwitch ConnData {connAgentVersion} = maybe False canAbort . rcvSwchSt
      -- if switch is in RSReceivedMessage status, aborting switch (deleting new queue)
      -- will break the connection because the sender would have original queue deleted
      RSReceivedMessage -> False
+      RSReceivedQEND -> False

 data ClientNtfCreds = ClientNtfCreds
  { -- | key pair to be used by the notification server to authorize transmissions
@@ -76,6 +76,7 @@ module Simplex.Messaging.Agent.Store.AgentStore
    getExpiredServiceConns,
    deleteExpiredServiceRequests,
    getDeletedWaitingDeliveryConnIds,
+    getConnRatchetSync,
    setConnRatchetSync,
    addProcessedRatchetKeyHash,
    checkRatchetKeyHashExists,
@@ -99,6 +100,7 @@ module Simplex.Messaging.Agent.Store.AgentStore
    setSndQueuePrimary,
    deleteConnRcvQueue,
    incRcvDeleteErrors,
+    getEndedRcvQueueConnIds,
    deleteConnSndQueue,
    getPrimaryRcvQueue,
    getRcvQueue,
@@ -762,6 +764,10 @@ incRcvDeleteErrors :: DB.Connection -> RcvQueue -> IO ()
 incRcvDeleteErrors db RcvQueue {connId, dbQueueId} =
  DB.execute db "UPDATE rcv_queues SET delete_errors = delete_errors + 1 WHERE conn_id = ? AND rcv_queue_id = ?" (connId, dbQueueId)

+getEndedRcvQueueConnIds :: DB.Connection -> IO [ConnId]
+getEndedRcvQueueConnIds db =
+  map fromOnly <$> DB.query db "SELECT conn_id FROM rcv_queues WHERE switch_status = ? AND deleted = 0" (Only RSReceivedQEND)
+
 deleteConnRcvQueue :: DB.Connection -> RcvQueue -> IO ()
 deleteConnRcvQueue db RcvQueue {connId, dbQueueId} =
  DB.execute db "DELETE FROM rcv_queues WHERE conn_id = ? AND rcv_queue_id = ?" (connId, dbQueueId)
@@ -1254,7 +1260,7 @@ getLastMsg db connId msgId =
        LEFT JOIN snd_messages s ON s.conn_id = r.conn_id AND s.rcpt_internal_id = r.internal_id
        WHERE r.conn_id = ? AND r.broker_id = ?
      |]
-      (connId, Binary msgId)
+      (connId, msgId)

 toRcvMsg :: (Int64, InternalTs, BrokerId, BrokerTs) :. (AgentMsgId, MsgIntegrity, MsgHash, AgentMessageType, MsgBody, PQEncryption, Maybe AgentMsgId, Maybe MsgReceiptStatus, BoolInt) -> RcvMsg
 toRcvMsg ((agentMsgId, internalTs, brokerId, brokerTs) :. (sndMsgId, integrity, internalHash, msgType, msgBody, pqEncryption, rcptInternalId_, rcptStatus_, BI userAck)) =
@@ -1286,7 +1292,7 @@ checkRcvMsgHashExists db connId hash =
 getRcvMsgBrokerTs :: DB.Connection -> ConnId -> SMP.MsgId -> IO (Either StoreError BrokerTs)
 getRcvMsgBrokerTs db connId msgId =
  firstRow fromOnly (SEMsgNotFound "getRcvMsgBrokerTs") $
-    DB.query db "SELECT broker_ts FROM rcv_messages WHERE conn_id = ? AND broker_id = ?" (connId, Binary msgId)
+    DB.query db "SELECT broker_ts FROM rcv_messages WHERE conn_id = ? AND broker_id = ?" (connId, msgId)

 deleteMsg :: DB.Connection -> ConnId -> InternalId -> IO ()
 deleteMsg db connId msgId =
@@ -1594,12 +1600,16 @@ getRatchet_ q db connId =
  where
    ratchet = maybe (Left SERatchetNotFound) Right . fromOnly

-getSkippedMsgKeys :: DB.Connection -> ConnId -> IO SkippedMsgKeys
-getSkippedMsgKeys db connId =
-  skipped <$> DB.query db "SELECT header_key, msg_n, msg_key FROM skipped_messages WHERE conn_id = ?" (Only connId)
+getSkippedMsgKeys :: DB.Connection -> ConnId -> Int -> IO SkippedMsgKeys
+getSkippedMsgKeys db connId maxKeys = do
+  (keys, oldKeys) <- splitAt maxKeys <$> DB.query db "SELECT skipped_message_id, header_key, msg_n, msg_key FROM skipped_messages WHERE conn_id = ? ORDER BY skipped_message_id DESC LIMIT ?" (connId, maxKeys + 1)
+  case oldKeys of
+    (skippedMsgId :: Int64, _, _, _) : _ -> DB.execute db "DELETE FROM skipped_messages WHERE conn_id = ? AND skipped_message_id <= ?" (connId, skippedMsgId)
+    [] -> pure ()
+  pure $ skipped keys
  where
    skipped = foldl' addSkippedKey M.empty
-    addSkippedKey smks (hk, msgN, mk) = M.alter (Just . addMsgKey) hk smks
+    addSkippedKey smks (_, hk, msgN, mk) = M.alter (Just . addMsgKey) hk smks
      where
        addMsgKey = maybe (M.singleton msgN mk) (M.insert msgN mk)

@@ -2500,12 +2510,12 @@ getSubscriptionServers db onlyNeeded =

 -- TODO [certs rcv] check index for getting queues with service present
 getUserServerRcvQueueSubs :: DB.Connection -> UserId -> SMPServer -> Bool -> ServiceAssoc -> Int -> Maybe SMP.RecipientId -> IO [RcvQueueSub]
-getUserServerRcvQueueSubs db userId (SMPServer h p kh) onlyNeeded hasService limit cursor_ =
-  map toRcvQueueSub <$> case cursor_ of
+getUserServerRcvQueueSubs db userId srv@(SMPServer h p kh) onlyNeeded hasService limit cursor_ =
+  map (toServerRcvQueueSub srv) <$> case cursor_ of
    Nothing -> DB.query db (q <> orderLimit) (userId, h, p, kh, limit)
    Just cursor -> DB.query db (q <> " AND q.rcv_id > ? " <> orderLimit) (userId, h, p, kh, cursor, limit)
  where
-    q = rcvQueueSubQuery <> toSubscribe <> " c.deleted = 0 AND q.deleted = 0 AND c.user_id = ? AND q.host = ? AND q.port = ? AND COALESCE(q.server_key_hash, s.key_hash) = ?" <> serviceCond
+    q = serverRcvQueueSubQuery <> toSubscribe <> " c.deleted = 0 AND q.deleted = 0 AND c.user_id = ? AND q.host = ? AND q.port = ? AND COALESCE(q.server_key_hash, s.key_hash) = ?" <> serviceCond
    orderLimit = " ORDER BY q.rcv_id LIMIT ?"
    toSubscribe
      | onlyNeeded = " WHERE q.to_subscribe = 1 AND "
@@ -2518,7 +2528,7 @@ unassocUserServerRcvQueueSubs :: DB.Connection -> UserId -> SMPServer -> IO [Rcv
 unassocUserServerRcvQueueSubs db userId srv@(SMPServer h p kh) = do
  deleteClientService db userId srv
 #if defined(dbPostgres)
-  map toRcvQueueSub
+  map (toServerRcvQueueSub srv)
    <$> DB.query
      db
      (removeRcvAssocsQuery <> " " <> returningColumns)
@@ -2526,15 +2536,15 @@ unassocUserServerRcvQueueSubs db userId srv@(SMPServer h p kh) = do
  where
    returningColumns =
      [sql|
-        RETURNING c.user_id, rcv_queues.conn_id, rcv_queues.host, rcv_queues.port, COALESCE(rcv_queues.server_key_hash, s.key_hash),
+        RETURNING c.user_id, rcv_queues.conn_id,
          rcv_queues.rcv_id, rcv_queues.rcv_private_key, rcv_queues.status, c.enable_ntfs, rcv_queues.client_notice_id,
          rcv_queues.rcv_queue_id, rcv_queues.rcv_primary, rcv_queues.replace_rcv_queue_id
      |]
 #else
-  qs <- map toRcvQueueSub
+  qs <- map (toServerRcvQueueSub srv)
    <$> DB.query
      db
-      (rcvQueueSubQuery <> " WHERE c.user_id = ? AND q.host = ? AND q.port = ? AND COALESCE(q.server_key_hash, s.key_hash) = ? AND q.rcv_service_assoc = 1")
+      (serverRcvQueueSubQuery <> " WHERE c.user_id = ? AND q.host = ? AND q.port = ? AND COALESCE(q.server_key_hash, s.key_hash) = ? AND q.rcv_service_assoc = 1")
      (userId, h, p, kh)
  DB.execute db removeRcvAssocsQuery (h, p, userId, kh)
  pure qs
@@ -2793,6 +2803,11 @@ getDeletedWaitingDeliveryConnIds :: DB.Connection -> IO [ConnId]
 getDeletedWaitingDeliveryConnIds db =
  map fromOnly <$> DB.query_ db "SELECT conn_id FROM connections WHERE deleted_at_wait_delivery IS NOT NULL"

+getConnRatchetSync :: DB.Connection -> ConnId -> IO (Either StoreError RatchetSyncState)
+getConnRatchetSync db connId =
+  firstRow fromOnly SEConnNotFound $
+    DB.query db "SELECT ratchet_sync_state FROM connections WHERE conn_id = ?" (Only connId)
+
 setConnRatchetSync :: DB.Connection -> ConnId -> RatchetSyncState -> IO ()
 setConnRatchetSync db connId ratchetSyncState =
  DB.execute db "UPDATE connections SET ratchet_sync_state = ? WHERE conn_id = ?" (ratchetSyncState, connId)
@@ -2814,21 +2829,35 @@ checkRatchetKeyHashExists db connId hash =
      (connId, Binary hash)

 deleteRatchetKeyHashesExpired :: DB.Connection -> NominalDiffTime -> Int -> IO ()
-deleteRatchetKeyHashesExpired db ttl limit = do
+deleteRatchetKeyHashesExpired db ttl maxConnHashes = do
  cutoffTs <- addUTCTime (-ttl) <$> getCurrentTime
+#if defined(dbPostgres)
  DB.execute
    db
-    [sql|
-      DELETE FROM processed_ratchet_key_hashes
-      WHERE processed_ratchet_key_hash_id IN (
-        SELECT processed_ratchet_key_hash_id
-        FROM processed_ratchet_key_hashes
-        WHERE created_at < ?
-        ORDER BY created_at ASC
-        LIMIT ?
-      )
-    |]
-    (cutoffTs, limit)
+    ("DELETE FROM processed_ratchet_key_hashes h USING (" <> maxExcessIdsQuery <> ") e WHERE h.conn_id = e.conn_id AND h.processed_ratchet_key_hash_id <= e.max_excess_id AND h.created_at < ?")
+    (maxConnHashes, maxConnHashes, cutoffTs)
+#else
+  maxExcessIds <- DB.query db maxExcessIdsQuery (maxConnHashes, maxConnHashes)
+  DB.executeMany
+    db
+    "DELETE FROM processed_ratchet_key_hashes WHERE conn_id = ? AND processed_ratchet_key_hash_id <= ? AND created_at < ?"
+    (map (\(connId :: ConnId, maxExcessId :: Int64) -> (connId, maxExcessId, cutoffTs)) maxExcessIds)
+#endif
+  where
+    maxExcessIdsQuery :: Query
+    maxExcessIdsQuery =
+      [sql|
+        SELECT conn_id, (
+          SELECT processed_ratchet_key_hash_id
+          FROM processed_ratchet_key_hashes
+          WHERE conn_id = c.conn_id
+          ORDER BY processed_ratchet_key_hash_id DESC
+          LIMIT 1 OFFSET ?
+        ) AS max_excess_id
+        FROM processed_ratchet_key_hashes c
+        GROUP BY conn_id
+        HAVING COUNT(*) > ?
+      |]

 -- | returns all connection queues, the first queue is the primary one
 getRcvQueuesByConnId_ :: DB.Connection -> ConnId -> IO (Maybe (NonEmpty RcvQueue))
@@ -2885,17 +2914,32 @@ getRcvQueueSubsByConnId_ db connId =
 rcvQueueSubQuery :: Query
 rcvQueueSubQuery =
  [sql|
-    SELECT c.user_id, q.conn_id, q.host, q.port, COALESCE(q.server_key_hash, s.key_hash), q.rcv_id, q.rcv_private_key, q.status, c.enable_ntfs, q.client_notice_id,
+    SELECT q.host, q.port, COALESCE(q.server_key_hash, s.key_hash), c.user_id, q.conn_id, q.rcv_id, q.rcv_private_key, q.status, c.enable_ntfs, q.client_notice_id,
      q.rcv_queue_id, q.rcv_primary, q.replace_rcv_queue_id
    FROM rcv_queues q
    JOIN servers s ON q.host = s.host AND q.port = s.port
    JOIN connections c ON q.conn_id = c.conn_id
  |]

-toRcvQueueSub :: (UserId, ConnId, NonEmpty TransportHost, ServiceName, C.KeyHash, SMP.RecipientId, SMP.RcvPrivateAuthKey) :. (QueueStatus, Maybe BoolInt, Maybe NoticeId, Int64, BoolInt, Maybe Int64) -> RcvQueueSub
-toRcvQueueSub ((userId, connId, host, port, keyHash, rcvId, rcvPrivateKey) :. (status, enableNtfs_, clientNoticeId, dbQueueId, BI primary, dbReplaceQueueId)) =
+serverRcvQueueSubQuery :: Query
+serverRcvQueueSubQuery =
+  [sql|
+    SELECT c.user_id, q.conn_id, q.rcv_id, q.rcv_private_key, q.status, c.enable_ntfs, q.client_notice_id,
+      q.rcv_queue_id, q.rcv_primary, q.replace_rcv_queue_id
+    FROM rcv_queues q
+    JOIN servers s ON q.host = s.host AND q.port = s.port
+    JOIN connections c ON q.conn_id = c.conn_id
+  |]
+
+type RcvQueueSubRow = (UserId, ConnId, SMP.RecipientId, SMP.RcvPrivateAuthKey) :. (QueueStatus, Maybe BoolInt, Maybe NoticeId, Int64, BoolInt, Maybe Int64)
+
+toRcvQueueSub :: (NonEmpty TransportHost, ServiceName, C.KeyHash) :. RcvQueueSubRow -> RcvQueueSub
+toRcvQueueSub ((host, port, keyHash) :. r) = toServerRcvQueueSub (SMPServer host port keyHash) r
+
+toServerRcvQueueSub :: SMPServer -> RcvQueueSubRow -> RcvQueueSub
+toServerRcvQueueSub server ((userId, connId, rcvId, rcvPrivateKey) :. (status, enableNtfs_, clientNoticeId, dbQueueId, BI primary, dbReplaceQueueId)) =
  let enableNtfs = maybe True unBI enableNtfs_
-   in RcvQueueSub {userId, connId, server = SMPServer host port keyHash, rcvId, rcvPrivateKey, status, enableNtfs, clientNoticeId, dbQueueId, primary, dbReplaceQueueId}
+   in RcvQueueSub {userId, connId, server, rcvId, rcvPrivateKey, status, enableNtfs, clientNoticeId, dbQueueId, primary, dbReplaceQueueId}

 getRcvQueueById :: DB.Connection -> ConnId -> Int64 -> IO (Either StoreError RcvQueue)
 getRcvQueueById db connId dbRcvId =
@@ -2996,7 +3040,7 @@ insertRcvMsgDetails_ db connId RcvQueue {dbQueueId} RcvMsgData {msgMeta, interna
      VALUES
        (?,?,?,?,?,?,?,?,?,?)
    |]
-    (connId, dbQueueId, internalRcvId, fst recipient, sndMsgId, Binary (fst broker), snd broker, Binary internalHash, Binary externalPrevSndHash, integrity)
+    (connId, dbQueueId, internalRcvId, fst recipient, sndMsgId, fst broker, snd broker, Binary internalHash, Binary externalPrevSndHash, integrity)
  DB.execute db "INSERT INTO encrypted_rcv_message_hashes (conn_id, hash) VALUES (?,?)" (connId, Binary encryptedMsgHash)

 updateRcvMsgHash :: DB.Connection -> ConnId -> AgentMsgId -> InternalRcvId -> MsgHash -> IO ()
@@ -3144,7 +3188,8 @@ createRcvFile db gVar userId fd@FileDescription {chunks} prefixPath tmpPath file
 createRcvFileRedirect :: DB.Connection -> TVar ChaChaDRG -> UserId -> FileDescription 'FRecipient -> FilePath -> FilePath -> CryptoFile -> FilePath -> CryptoFile -> Bool -> IO (Either StoreError RcvFileId)
 createRcvFileRedirect _ _ _ FileDescription {redirect = Nothing} _ _ _ _ _ _ = pure $ Left $ SEInternal "createRcvFileRedirect called without redirect"
 createRcvFileRedirect db gVar userId redirectFd@FileDescription {chunks = redirectChunks, redirect = Just RedirectFileInfo {size, digest}} prefixPath redirectPath redirectFile dstPath dstFile approvedRelays = runExceptT $ do
-  (dstEntityId, dstId) <- ExceptT $ insertRcvFile db gVar userId dummyDst prefixPath dstPath dstFile Nothing Nothing approvedRelays
+  nonce <- atomically $ C.randomCbNonce gVar
+  (dstEntityId, dstId) <- ExceptT $ insertRcvFile db gVar userId (dummyDst nonce) prefixPath dstPath dstFile Nothing Nothing approvedRelays
  (_, redirectId) <- ExceptT $ insertRcvFile db gVar userId redirectFd prefixPath redirectPath redirectFile (Just dstId) (Just dstEntityId) approvedRelays
  liftIO $
    forM_ redirectChunks $ \fc@FileChunk {replicas} -> do
@@ -3152,7 +3197,7 @@ createRcvFileRedirect db gVar userId redirectFd@FileDescription {chunks = redire
      forM_ (zip [1 ..] replicas) $ \(rno, replica) -> insertRcvFileChunkReplica db rno replica chunkId
  pure dstEntityId
  where
-    dummyDst =
+    dummyDst nonce =
      FileDescription
        { party = SFRecipient,
          size,
@@ -3160,7 +3205,7 @@ createRcvFileRedirect db gVar userId redirectFd@FileDescription {chunks = redire
          redirect = Nothing,
          -- updated later with updateRcvFileRedirect
          key = C.unsafeSbKey $ B.replicate 32 '#',
-          nonce = C.cbNonce "",
+          nonce,
          chunkSize = FileSize 0,
          chunks = []
        }
@@ -16,6 +16,8 @@ import Simplex.Messaging.Agent.Store.Postgres.Migrations.M20260411_service_certs
 import Simplex.Messaging.Agent.Store.Postgres.Migrations.M20260712_address_dr_rpc
 import Simplex.Messaging.Agent.Store.Postgres.Migrations.M20260823_snd_files_entitlement
 import Simplex.Messaging.Agent.Store.Postgres.Migrations.M20260919_ratchet_verify_codes
+import Simplex.Messaging.Agent.Store.Postgres.Migrations.M20260929_ratchet_indexes
+import Simplex.Messaging.Agent.Store.Postgres.Migrations.M20261008_rcv_switch_status
 import Simplex.Messaging.Agent.Store.Shared (Migration (..))

 schemaMigrations :: [(String, Text, Maybe Text)]
@@ -31,7 +33,9 @@ schemaMigrations =
    ("20260411_service_certs", m20260411_service_certs, Just down_m20260411_service_certs),
    ("20260712_address_dr_rpc", m20260712_address_dr_rpc, Just down_m20260712_address_dr_rpc),
    ("20260823_snd_files_entitlement", m20260823_snd_files_entitlement, Just down_m20260823_snd_files_entitlement),
-    ("20260919_ratchet_verify_codes", m20260919_ratchet_verify_codes, Just down_m20260919_ratchet_verify_codes)
+    ("20260919_ratchet_verify_codes", m20260919_ratchet_verify_codes, Just down_m20260919_ratchet_verify_codes),
+    ("20260929_ratchet_indexes", m20260929_ratchet_indexes, Just down_m20260929_ratchet_indexes),
+    ("20261008_rcv_switch_status", m20261008_rcv_switch_status, Just down_m20261008_rcv_switch_status)
  ]

 -- | The list of migrations in ascending order by date
@@ -0,0 +1,34 @@
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE QuasiQuotes #-}
+
+module Simplex.Messaging.Agent.Store.Postgres.Migrations.M20260929_ratchet_indexes where
+
+import Data.Text (Text)
+import Text.RawString.QQ (r)
+
+m20260929_ratchet_indexes :: Text
+m20260929_ratchet_indexes =
+  [r|
+DROP INDEX idx_skipped_messages_conn_id;
+CREATE INDEX idx_skipped_messages_conn_id ON skipped_messages(conn_id, skipped_message_id);
+
+DELETE FROM processed_ratchet_key_hashes AS h
+WHERE EXISTS (
+  SELECT 1 FROM processed_ratchet_key_hashes d
+  WHERE d.conn_id = h.conn_id AND d.hash = h.hash AND d.processed_ratchet_key_hash_id < h.processed_ratchet_key_hash_id
+);
+
+DROP INDEX idx_processed_ratchet_key_hashes_hash;
+CREATE UNIQUE INDEX idx_processed_ratchet_key_hashes_hash ON processed_ratchet_key_hashes(conn_id, hash);
+CREATE INDEX idx_processed_ratchet_key_hashes_conn_id ON processed_ratchet_key_hashes(conn_id, processed_ratchet_key_hash_id);
+|]
+
+down_m20260929_ratchet_indexes :: Text
+down_m20260929_ratchet_indexes =
+  [r|
+DROP INDEX idx_processed_ratchet_key_hashes_conn_id;
+DROP INDEX idx_processed_ratchet_key_hashes_hash;
+CREATE INDEX idx_processed_ratchet_key_hashes_hash ON processed_ratchet_key_hashes(conn_id, hash);
+DROP INDEX idx_skipped_messages_conn_id;
+CREATE INDEX idx_skipped_messages_conn_id ON skipped_messages(conn_id);
+|]
@@ -0,0 +1,20 @@
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE QuasiQuotes #-}
+
+module Simplex.Messaging.Agent.Store.Postgres.Migrations.M20261008_rcv_switch_status where
+
+import Data.Text (Text)
+import Text.RawString.QQ (r)
+
+m20261008_rcv_switch_status :: Text
+m20261008_rcv_switch_status =
+  [r|
+CREATE INDEX idx_rcv_queues_switch_status ON rcv_queues(switch_status);
+|]
+
+down_m20261008_rcv_switch_status :: Text
+down_m20261008_rcv_switch_status =
+  [r|
+UPDATE rcv_queues SET switch_status = NULL WHERE switch_status = 'received_qend';
+DROP INDEX idx_rcv_queues_switch_status;
+|]
@@ -1169,11 +1169,15 @@ CREATE INDEX idx_ntf_tokens_ntf_host_ntf_port ON smp_agent_test_protocol_schema.



+CREATE INDEX idx_processed_ratchet_key_hashes_conn_id ON smp_agent_test_protocol_schema.processed_ratchet_key_hashes USING btree (conn_id, processed_ratchet_key_hash_id);
+
+
+
 CREATE INDEX idx_processed_ratchet_key_hashes_created_at ON smp_agent_test_protocol_schema.processed_ratchet_key_hashes USING btree (created_at);



-CREATE INDEX idx_processed_ratchet_key_hashes_hash ON smp_agent_test_protocol_schema.processed_ratchet_key_hashes USING btree (conn_id, hash);
+CREATE UNIQUE INDEX idx_processed_ratchet_key_hashes_hash ON smp_agent_test_protocol_schema.processed_ratchet_key_hashes USING btree (conn_id, hash);



@@ -1229,6 +1233,10 @@ CREATE UNIQUE INDEX idx_rcv_queues_ntf ON smp_agent_test_protocol_schema.rcv_que



+CREATE INDEX idx_rcv_queues_switch_status ON smp_agent_test_protocol_schema.rcv_queues USING btree (switch_status);
+
+
+
 CREATE INDEX idx_rcv_queues_to_subscribe ON smp_agent_test_protocol_schema.rcv_queues USING btree (to_subscribe);


@@ -1241,7 +1249,7 @@ CREATE UNIQUE INDEX idx_server_certs_user_id_host_port ON smp_agent_test_protoco



-CREATE INDEX idx_skipped_messages_conn_id ON smp_agent_test_protocol_schema.skipped_messages USING btree (conn_id);
+CREATE INDEX idx_skipped_messages_conn_id ON smp_agent_test_protocol_schema.skipped_messages USING btree (conn_id, skipped_message_id);



@@ -100,7 +100,8 @@ withTransaction st = withTransactionPriority st False
 {-# INLINE withTransaction #-}

 withTransactionPriority :: DBStore -> Bool -> (DB.Connection -> IO a) -> IO a
-withTransactionPriority st priority action = withConnectionPriority st priority $ dbBusyLoop . transaction
+withTransactionPriority st@DBStore {dbClosed} priority action = withConnectionPriority st priority $ \db ->
+  ifM (readTVarIO dbClosed) (fail "withTransaction: database closed") (dbBusyLoop $ transaction db)
  where
    transaction db@DB.Connection {conn} = SQL.withImmediateTransaction conn $ action db

@@ -52,6 +52,9 @@ import Simplex.Messaging.Agent.Store.SQLite.Migrations.M20260411_service_certs
 import Simplex.Messaging.Agent.Store.SQLite.Migrations.M20260712_address_dr_rpc
 import Simplex.Messaging.Agent.Store.SQLite.Migrations.M20260823_snd_files_entitlement
 import Simplex.Messaging.Agent.Store.SQLite.Migrations.M20260919_ratchet_verify_codes
+import Simplex.Messaging.Agent.Store.SQLite.Migrations.M20260929_ratchet_indexes
+import Simplex.Messaging.Agent.Store.SQLite.Migrations.M20261005_commands_autoincrement
+import Simplex.Messaging.Agent.Store.SQLite.Migrations.M20261008_rcv_switch_status
 import Simplex.Messaging.Agent.Store.Shared (Migration (..))

 schemaMigrations :: [(String, Query, Maybe Query)]
@@ -103,7 +106,10 @@ schemaMigrations =
    ("m20260411_service_certs", m20260411_service_certs, Just down_m20260411_service_certs),
    ("m20260712_address_dr_rpc", m20260712_address_dr_rpc, Just down_m20260712_address_dr_rpc),
    ("m20260823_snd_files_entitlement", m20260823_snd_files_entitlement, Just down_m20260823_snd_files_entitlement),
-    ("m20260919_ratchet_verify_codes", m20260919_ratchet_verify_codes, Just down_m20260919_ratchet_verify_codes)
+    ("m20260919_ratchet_verify_codes", m20260919_ratchet_verify_codes, Just down_m20260919_ratchet_verify_codes),
+    ("m20260929_ratchet_indexes", m20260929_ratchet_indexes, Just down_m20260929_ratchet_indexes),
+    ("m20261005_commands_autoincrement", m20261005_commands_autoincrement, Just down_m20261005_commands_autoincrement),
+    ("m20261008_rcv_switch_status", m20261008_rcv_switch_status, Just down_m20261008_rcv_switch_status)
  ]

 -- | The list of migrations in ascending order by date
@@ -0,0 +1,29 @@
+{-# LANGUAGE QuasiQuotes #-}
+
+module Simplex.Messaging.Agent.Store.SQLite.Migrations.M20260929_ratchet_indexes where
+
+import Database.SQLite.Simple (Query)
+import Database.SQLite.Simple.QQ (sql)
+
+-- idx_skipped_messages_conn_id is not changed: SQLite index entries include rowid (skipped_message_id)
+m20260929_ratchet_indexes :: Query
+m20260929_ratchet_indexes =
+  [sql|
+DELETE FROM processed_ratchet_key_hashes AS h
+WHERE EXISTS (
+  SELECT 1 FROM processed_ratchet_key_hashes d
+  WHERE d.conn_id = h.conn_id AND d.hash = h.hash AND d.processed_ratchet_key_hash_id < h.processed_ratchet_key_hash_id
+);
+
+DROP INDEX idx_processed_ratchet_key_hashes_hash;
+CREATE UNIQUE INDEX idx_processed_ratchet_key_hashes_hash ON processed_ratchet_key_hashes(conn_id, hash);
+CREATE INDEX idx_processed_ratchet_key_hashes_conn_id ON processed_ratchet_key_hashes(conn_id, processed_ratchet_key_hash_id);
+  |]
+
+down_m20260929_ratchet_indexes :: Query
+down_m20260929_ratchet_indexes =
+  [sql|
+DROP INDEX idx_processed_ratchet_key_hashes_conn_id;
+DROP INDEX idx_processed_ratchet_key_hashes_hash;
+CREATE INDEX idx_processed_ratchet_key_hashes_hash ON processed_ratchet_key_hashes(conn_id, hash);
+  |]
@@ -0,0 +1,33 @@
+{-# LANGUAGE QuasiQuotes #-}
+
+module Simplex.Messaging.Agent.Store.SQLite.Migrations.M20261005_commands_autoincrement where
+
+import Database.SQLite.Simple (Query)
+import Database.SQLite.Simple.QQ (sql)
+
+m20261005_commands_autoincrement :: Query
+m20261005_commands_autoincrement =
+  [sql|
+INSERT INTO sqlite_sequence (name, seq)
+SELECT 'commands', MAX(ROWID) FROM commands;
+
+PRAGMA writable_schema=1;
+
+UPDATE sqlite_master SET sql = replace(sql, 'command_id INTEGER PRIMARY KEY,', 'command_id INTEGER PRIMARY KEY AUTOINCREMENT,')
+WHERE name = 'commands' AND type = 'table';
+
+PRAGMA writable_schema=RESET;
+  |]
+
+down_m20261005_commands_autoincrement :: Query
+down_m20261005_commands_autoincrement =
+  [sql|
+DELETE FROM sqlite_sequence WHERE name = 'commands';
+
+PRAGMA writable_schema=1;
+
+UPDATE sqlite_master SET sql = replace(sql, 'command_id INTEGER PRIMARY KEY AUTOINCREMENT,', 'command_id INTEGER PRIMARY KEY,')
+WHERE name = 'commands' AND type = 'table';
+
+PRAGMA writable_schema=RESET;
+  |]
@@ -0,0 +1,19 @@
+{-# LANGUAGE QuasiQuotes #-}
+
+module Simplex.Messaging.Agent.Store.SQLite.Migrations.M20261008_rcv_switch_status where
+
+import Database.SQLite.Simple (Query)
+import Database.SQLite.Simple.QQ (sql)
+
+m20261008_rcv_switch_status :: Query
+m20261008_rcv_switch_status =
+  [sql|
+CREATE INDEX idx_rcv_queues_switch_status ON rcv_queues(switch_status);
+|]
+
+down_m20261008_rcv_switch_status :: Query
+down_m20261008_rcv_switch_status =
+  [sql|
+UPDATE rcv_queues SET switch_status = NULL WHERE switch_status = 'received_qend';
+DROP INDEX idx_rcv_queues_switch_status;
+|]
@@ -247,7 +247,7 @@ CREATE TABLE ntf_subscriptions(
  ON DELETE RESTRICT ON UPDATE CASCADE
 ) WITHOUT ROWID, STRICT;
 CREATE TABLE commands(
-  command_id INTEGER PRIMARY KEY,
+  command_id INTEGER PRIMARY KEY AUTOINCREMENT,
  conn_id BLOB NOT NULL REFERENCES connections ON DELETE CASCADE,
  host TEXT,
  port TEXT,
@@ -261,6 +261,7 @@ CREATE TABLE commands(
  FOREIGN KEY(host, port) REFERENCES servers
  ON DELETE RESTRICT ON UPDATE CASCADE
 ) STRICT;
+CREATE TABLE sqlite_sequence(name,seq);
 CREATE TABLE snd_message_deliveries(
  snd_message_delivery_id INTEGER PRIMARY KEY AUTOINCREMENT,
  conn_id BLOB NOT NULL REFERENCES connections ON DELETE CASCADE,
@@ -269,7 +270,6 @@ CREATE TABLE snd_message_deliveries(
  failed INTEGER DEFAULT 0,
  FOREIGN KEY(conn_id, internal_id) REFERENCES messages ON DELETE CASCADE DEFERRABLE INITIALLY DEFERRED
 ) STRICT;
-CREATE TABLE sqlite_sequence(name,seq);
 CREATE TABLE users(
  user_id INTEGER PRIMARY KEY AUTOINCREMENT
  ,
@@ -573,10 +573,6 @@ CREATE INDEX idx_encrypted_rcv_message_hashes_hash ON encrypted_rcv_message_hash
  conn_id,
  hash
 );
-CREATE INDEX idx_processed_ratchet_key_hashes_hash ON processed_ratchet_key_hashes(
-  conn_id,
-  hash
-);
 CREATE INDEX idx_snd_messages_rcpt_internal_id ON snd_messages(
  conn_id,
  rcpt_internal_id
@@ -641,6 +637,15 @@ CREATE INDEX idx_connections_deleted ON connections(deleted);
 CREATE INDEX idx_connections_service_request_expires_at ON connections(
  service_request_expires_at
 );
+CREATE UNIQUE INDEX idx_processed_ratchet_key_hashes_hash ON processed_ratchet_key_hashes(
+  conn_id,
+  hash
+);
+CREATE INDEX idx_processed_ratchet_key_hashes_conn_id ON processed_ratchet_key_hashes(
+  conn_id,
+  processed_ratchet_key_hash_id
+);
+CREATE INDEX idx_rcv_queues_switch_status ON rcv_queues(switch_status);
 CREATE TRIGGER tr_rcv_queue_insert
 AFTER INSERT ON rcv_queues
 FOR EACH ROW
@@ -67,6 +67,7 @@ module Simplex.Messaging.Client
    enableSMPQueuesNtfs,
    disableSMPQueuesNtfs,
    sendSMPMessage,
+    QueueDrained,
    ackSMPMessage,
    suspendSMPQueue,
    deleteSMPQueue,
@@ -160,7 +161,6 @@ import Network.Socket (HostName, ServiceName)
 import Network.Socks5 (SocksCredentials (..))
 import Numeric.Natural
 import qualified Simplex.Messaging.Crypto as C
-import Simplex.Messaging.Crypto.Entitlement (EntitlementProof)
 import Simplex.Messaging.Encoding
 import Simplex.Messaging.Encoding.String
 import Simplex.Messaging.Parsers (defaultJSON, dropPrefix, enumJSON, sumTypeJSON)
@@ -196,6 +196,7 @@ data PClient v err msg = PClient
    transportHost :: TransportHost,
    tcpConnectTimeout :: NetworkTimeout,
    tcpTimeout :: NetworkTimeout,
+    proxiedRelayVRange :: VersionRange v,
    sendPings :: TVar Bool,
    lastReceived :: TVar UTCTime,
    timeoutErrorCount :: TVar Int,
@@ -241,6 +242,7 @@ smpClientStub g sessionId thVersion thAuth = do
              transportHost = "localhost",
              tcpConnectTimeout,
              tcpTimeout,
+              proxiedRelayVRange = supportedClientSMPRelayVRange,
              sendPings,
              lastReceived,
              timeoutErrorCount,
@@ -478,14 +480,13 @@ data ProtocolClientConfig v = ProtocolClientConfig
    serviceCredentials :: Maybe ServiceCredentials,
    -- | client-server protocol version range
    serverVRange :: VersionRange v,
+    proxiedRelayVRange :: VersionRange v,
    -- | agree shared session secret (used in SMP proxy for additional encryption layer)
    agreeSecret :: Bool,
    -- | Whether connecting client is a proxy server. See comment in ClientHandshake
    proxyServer :: Bool,
    -- | send SNI to server, False for SMP
-    useSNI :: Bool,
-    -- | proof of the user entitlement to send in the handshake, bound to the session
-    mkEntitlementProof :: SessionId -> IO (Maybe EntitlementProof)
+    useSNI :: Bool
  }

 -- | Default protocol client configuration.
@@ -498,10 +499,10 @@ defaultClientConfig clientALPN useSNI serverVRange =
      clientALPN,
      serviceCredentials = Nothing,
      serverVRange,
+      proxiedRelayVRange = serverVRange,
      agreeSecret = False,
      proxyServer = False,
-      useSNI,
-      mkEntitlementProof = \_ -> pure Nothing
+      useSNI
    }
 {-# INLINE defaultClientConfig #-}

@@ -509,6 +510,7 @@ defaultSMPClientConfig :: ProtocolClientConfig SMPVersion
 defaultSMPClientConfig =
  (defaultClientConfig (Just alpnSupportedSMPHandshakes) False supportedClientSMPRelayVRange)
    { defaultTransport = (show defaultSMPPort, transport @TLS),
+      proxiedRelayVRange = supportedClientSMPRelayVRange,
      agreeSecret = True
    }
 {-# INLINE defaultSMPClientConfig #-}
@@ -572,7 +574,7 @@ type SMPTransportSession = TransportSession BrokerMsg
 -- A single queue can be used for multiple 'SMPClient' instances,
 -- as 'SMPServerTransmission' includes server information.
 getProtocolClient :: forall v err msg. Protocol v err msg => TVar ChaChaDRG -> NetworkRequestMode -> TransportSession msg -> ProtocolClientConfig v -> [HostName] -> Maybe (TBQueue (ServerTransmissionBatch v err msg)) -> UTCTime -> (ProtocolClient v err msg -> IO ()) -> IO (Either (ProtocolClientError err) (ProtocolClient v err msg))
-getProtocolClient g nm transportSession@(_, srv, _) cfg@ProtocolClientConfig {qSize, networkConfig, clientALPN, serviceCredentials, serverVRange, agreeSecret, proxyServer, useSNI, mkEntitlementProof} presetDomains msgQ proxySessTs disconnected = do
+getProtocolClient g nm transportSession@(_, srv, _) cfg@ProtocolClientConfig {qSize, networkConfig, clientALPN, serviceCredentials, serverVRange, proxiedRelayVRange, agreeSecret, proxyServer, useSNI} presetDomains msgQ proxySessTs disconnected = do
  case chooseTransportHost networkConfig (host srv) of
    Right useHost ->
      (getCurrentTime >>= mkProtocolClient useHost >>= runClient useTransport useHost)
@@ -597,6 +599,7 @@ getProtocolClient g nm transportSession@(_, srv, _) cfg@ProtocolClientConfig {qS
            transportHost,
            tcpConnectTimeout,
            tcpTimeout,
+            proxiedRelayVRange,
            sendPings,
            lastReceived,
            timeoutErrorCount,
@@ -639,7 +642,7 @@ getProtocolClient g nm transportSession@(_, srv, _) cfg@ProtocolClientConfig {qS
    client _ c cVar h = do
      ks <- if agreeSecret then Just <$> atomically (C.generateKeyPair g) else pure Nothing
      serviceKeys_ <- mapM (\creds -> (creds,) <$> atomically (C.generateKeyPair g)) serviceCredentials
-      runExceptT (protocolClientHandshake @v @err @msg h ks (keyHash srv) serverVRange proxyServer serviceKeys_ mkEntitlementProof) >>= \case
+      runExceptT (protocolClientHandshake @v @err @msg h ks (keyHash srv) serverVRange proxyServer serviceKeys_) >>= \case
        Left e -> atomically . putTMVar cVar . Left $ PCETransportError e
        Right th@THandle {params} -> do
          sessionTs <- getCurrentTime
@@ -1085,15 +1088,17 @@ resolvedNameOrNotFound d NameResponse {registration} = case registration of
  NRRegistered {nameRecord} -> T.toLower (nrName nameRecord) == fullDomainName d
  _ -> True

+type QueueDrained = Bool
+
 -- | Acknowledge message delivery (server deletes the message).
 --
 -- https://github.com/simplex-chat/simplexmq/blob/master/protocol/simplex-messaging.md#acknowledge-message-delivery
 -- This command is always sent in background request mode
-ackSMPMessage :: SMPClient -> RcvPrivateAuthKey -> QueueId -> MsgId -> ExceptT SMPClientError IO ()
+ackSMPMessage :: SMPClient -> RcvPrivateAuthKey -> QueueId -> MsgId -> ExceptT SMPClientError IO QueueDrained
 ackSMPMessage c rpKey rId msgId =
  sendSMPCommand c NRMBackground (Just rpKey) rId (ACK msgId) >>= \case
-    OK -> return ()
-    cmd@MSG {} -> liftIO $ writeSMPMessage c rId cmd
+    OK -> pure True
+    cmd@MSG {} -> liftIO (writeSMPMessage c rId cmd) $> False
    r -> throwE $ unexpectedResponse r

 -- | Irreversibly suspend SMP queue.
@@ -1119,10 +1124,10 @@ deleteSMPQueues = okSMPCommands DEL
 -- send PRXY :: SMPServer -> Maybe BasicAuth -> Command Sender
 -- receives PKEY :: SessionId -> X.CertificateChain -> X.SignedExact X.PubKey -> BrokerMsg
 connectSMPProxiedRelay :: SMPClient -> NetworkRequestMode -> SMPServer -> Maybe BasicAuth -> ExceptT SMPClientError IO ProxiedRelay
-connectSMPProxiedRelay c@ProtocolClient {client_ = PClient {tcpConnectTimeout, tcpTimeout}} nm relayServ@ProtocolServer {port = relayPort, keyHash = C.KeyHash kh} proxyAuth =
+connectSMPProxiedRelay c@ProtocolClient {client_ = PClient {tcpConnectTimeout, tcpTimeout, proxiedRelayVRange}} nm relayServ@ProtocolServer {port = relayPort, keyHash = C.KeyHash kh} proxyAuth =
  sendProtocolCommand_ c nm Nothing tOut Nothing NoEntity (Cmd SProxiedClient (PRXY relayServ proxyAuth)) >>= \case
    PKEY sId vr (CertChainPubKey chain key) ->
-      case supportedClientSMPRelayVRange `compatibleVersion` vr of
+      case proxiedRelayVRange `compatibleVersion` vr of
        Nothing -> throwE $ transportErr TEVersion
        Just (Compatible v) -> do
          relayKey <- liftEitherWith (const $ transportErr $ TEHandshake IDENTITY) =<< liftIO (runExceptT $ validateRelay chain key)
@@ -1173,7 +1178,7 @@ instance StrEncoding ProxyClientError where
 -- consider how to process slow responses - is it handled somehow locally or delegated to the caller
 -- this method is used in the client
 -- sends PFWD :: C.PublicKeyX25519 -> EncTransmission -> Command Sender
-- receives PRES :: EncResponse -> BrokerMsg -- proxy to client
+-- receives PRES :: Maybe C.CbNonce -> EncResponse -> BrokerMsg -- proxy to client

 -- When client sends message via proxy, there may be one successful scenario and 9 error scenarios
 -- as shown below (WTF stands for unexpected response, ??? for response that failed to parse).
@@ -1226,20 +1231,20 @@ proxySMPCommand c@ProtocolClient {thParams = proxyThParams, client_ = PClient {c
  -- encode
  let TransmissionForAuth {tForAuth, tToSend} = encodeTransmissionForAuth serverThParams (CorrId corrId, sId, Cmd (sParty @p) command)
  -- serviceAuth is False here – proxied commands are not used with service certificates
-  auth <- liftEitherWith PCETransportError $ authTransmission serverThAuth False spKey nonce tForAuth
+  auth <- liftEitherWith PCETransportError $ authTransmission serverThAuth False spKey (Just nonce) tForAuth
  b <- case batchTransmissions serverThParams [Right (auth, tToSend)] of
    [] -> throwE $ PCETransportError TELargeMsg
    TBError e _ : _ -> throwE $ PCETransportError e
    TBTransmission s _ : _ -> pure s
    TBTransmissions s _ _ : _ -> pure s
-  et <- liftEitherWith PCECryptoError $ EncTransmission <$> C.cbEncrypt cmdSecret nonce b paddedProxiedTLength
+  et <- liftEitherWith PCECryptoError $ EncTransmission <$> C.cbEncrypt cmdSecret (encTransmissionNonce v nonce) b paddedProxiedTLength
  -- proxy interaction errors are wrapped
  let tOut = Just $ 2 * netTimeoutInt tcpTimeout nm
  tryE (sendProtocolCommand_ c nm (Just nonce) tOut Nothing (EntityId sessionId) (Cmd SProxiedClient (PFWD v cmdPubKey et))) >>= \case
    Right r -> case r of
-      PRES (EncResponse er) -> do
+      PRES nonce_ (EncResponse er) -> do
        -- server interaction errors are thrown directly
-        t' <- liftEitherWith PCECryptoError $ C.cbDecrypt cmdSecret (C.reverseNonce nonce) er
+        t' <- liftEitherWith PCECryptoError $ C.cbDecrypt cmdSecret (fromMaybe (C.reverseNonce nonce) nonce_) er
        case tParse serverThParams t' of
          t'' :| [] -> case tDecodeClient serverThParams t'' of
            (_, _, cmd) -> case cmd of
@@ -1257,10 +1262,10 @@ proxySMPCommand c@ProtocolClient {thParams = proxyThParams, client_ = PClient {c

 -- this method is used in the proxy
 -- sends RFWD :: EncFwdTransmission -> Command Sender
-- receives RRES :: EncFwdResponse -> BrokerMsg
+-- receives RRES :: Maybe C.CbNonce -> EncFwdResponse -> BrokerMsg
 -- proxy should send PRES to the client with EncResponse
 -- Always uses background timeout mode
-forwardSMPTransmission :: SMPClient -> CorrId -> VersionSMP -> C.PublicKeyX25519 -> EncTransmission -> ExceptT SMPClientError IO EncResponse
+forwardSMPTransmission :: SMPClient -> C.CorrCbNonce -> VersionSMP -> C.PublicKeyX25519 -> EncTransmission -> ExceptT SMPClientError IO (Maybe C.CbNonce, EncResponse)
 forwardSMPTransmission c@ProtocolClient {thParams, client_ = PClient {clientCorrId = g}} fwdCorrId fwdVersion fwdKey fwdTransmission = do
  -- prepare params
  sessSecret <- case thAuth thParams of
@@ -1272,11 +1277,11 @@ forwardSMPTransmission c@ProtocolClient {thParams, client_ = PClient {clientCorr
      eft = EncFwdTransmission $ C.cbEncryptNoPad sessSecret nonce (smpEncode fwdT)
  -- send
  sendProtocolCommand_ c NRMBackground (Just nonce) Nothing Nothing NoEntity (Cmd SProxyService (RFWD eft)) >>= \case
-    RRES (EncFwdResponse efr) -> do
+    RRES nonce_ (EncFwdResponse efr) -> do
      -- unwrap
      r' <- liftEitherWith PCECryptoError $ C.cbDecryptNoPad sessSecret (C.reverseNonce nonce) efr
      FwdResponse {fwdCorrId = _, fwdResponse} <- liftEitherWith (const $ PCEResponseError BLOCK) $ smpDecode r'
-      pure fwdResponse
+      pure (nonce_, fwdResponse)
    r -> throwE $ unexpectedResponse r

 -- get queue information - always sent interactively
@@ -1398,7 +1403,7 @@ mkTransmission_ :: forall v err msg. Protocol v err msg => ProtocolClient v err
 mkTransmission_ ProtocolClient {thParams, client_ = PClient {clientCorrId, sentCommands}} nonce_ (entityId, pKey_, command) = do
  nonce@(C.CbNonce corrId) <- maybe (atomically $ C.randomCbNonce clientCorrId) pure nonce_
  let TransmissionForAuth {tForAuth, tToSend} = encodeTransmissionForAuth thParams (CorrId corrId, entityId, command)
-      auth = authTransmission (thAuth thParams) (useServiceAuth command) pKey_ nonce tForAuth
+      auth = authTransmission (thAuth thParams) (useServiceAuth command) pKey_ (Just nonce) tForAuth
  r <- mkRequest (CorrId corrId)
  pure ((,tToSend) <$> auth, r)
  where
@@ -1417,14 +1422,14 @@ mkTransmission_ ProtocolClient {thParams, client_ = PClient {clientCorrId, sentC
      atomically $ TM.insert corrId r sentCommands
      pure r

-authTransmission :: Maybe (THandleAuth 'TClient) -> Bool -> Maybe C.APrivateAuthKey -> C.CbNonce -> ByteString -> Either TransportError (Maybe TAuthorizations)
-authTransmission thAuth serviceAuth pKey_ nonce t = traverse authenticate pKey_
+authTransmission :: Maybe (THandleAuth 'TClient) -> Bool -> Maybe C.APrivateAuthKey -> Maybe C.CbNonce -> ByteString -> Either TransportError (Maybe TAuthorizations)
+authTransmission thAuth serviceAuth pKey_ nonce_ t = traverse authenticate pKey_
  where
    authenticate :: C.APrivateAuthKey -> Either TransportError TAuthorizations
    authenticate (C.APrivateAuthKey a pk) = (,serviceSig) <$> case a of
-      C.SX25519 -> case thAuth of
-        Just THAuthClient {peerServerPubKey = k} -> Right $ TAAuthenticator $ C.cbAuthenticate k pk nonce t'
-        Nothing -> Left TENoServerAuth
+      C.SX25519 -> case (thAuth, nonce_) of
+        (Just THAuthClient {peerServerPubKey = k}, Just nonce) -> Right $ TAAuthenticator $ C.cbAuthenticate k pk nonce t'
+        _ -> Left TENoServerAuth
      C.SEd25519 -> sign pk
      C.SEd448 -> sign pk
    -- When command is signed by both entity key and service key,
@@ -140,8 +140,10 @@ module Simplex.Messaging.Crypto
    gcmIV,

    -- * NaCl crypto_box
-    CbNonce (unCbNonce),
+    CbNonceI (..),
+    CbNonce,
    pattern CbNonce,
+    CorrCbNonce,
    cbEncrypt,
    cbEncryptNoPad,
    cbEncryptMaxLenBS,
@@ -152,8 +154,12 @@ module Simplex.Messaging.Crypto
    sbEncryptNoPad,
    sbDecryptNoPad,
    cbNonce,
+    unsafeCbNonce,
+    corrCbNonce,
    randomCbNonce,
    reverseNonce,
+    xorNonce,
+    toCbNonce,

    -- * NaCl crypto_secretbox
    SbKey (unSbKey),
@@ -232,6 +238,7 @@ import Data.ASN1.Types
 import Data.Aeson (FromJSON (..), ToJSON (..))
 import qualified Data.Attoparsec.ByteString.Char8 as A
 import Data.Bifunctor (bimap, first)
+import Data.Bits (xor)
 import Data.ByteArray (ByteArrayAccess)
 import qualified Data.ByteArray as BA
 import Data.ByteString.Base64 (decode)
@@ -254,7 +261,7 @@ import Simplex.Messaging.Agent.Store.DB (Binary (..), FromField (..), ToField (.
 import Simplex.Messaging.Encoding
 import Simplex.Messaging.Encoding.String
 import Simplex.Messaging.Parsers (parseAll, parseString)
-import Simplex.Messaging.Util ((<$?>))
+import Simplex.Messaging.Util (packZipWith, (<$?>))

 -- | Cryptographic algorithms.
 data Algorithm = Ed25519 | Ed448 | X25519 | X448
@@ -931,6 +938,8 @@ data CryptoError
    CERatchetEarlierMessage Word32
  | -- | duplicate message number
    CERatchetDuplicateMessage
+  | -- | KEM key generation failed, indicating a broken RNG
+    CryptoKEMKeyGenError
  deriving (Eq, Show, Exception)

 aesKeySize :: Int
@@ -1045,9 +1054,7 @@ md5Hash = BA.convert . (hash :: ByteString -> Digest MD5)

 -- | AEAD-GCM encryption with associated data.
 --
-- Used as part of double ratchet encryption.
-- This function requires 16 bytes IV, it transforms IV in cryptonite_aes_gcm_init here:
-- https://github.com/haskell-crypto/cryptonite/blob/master/cbits/cryptonite_aes.c
+-- Used as part of double ratchet encryption, with a 16-byte IV (see @initAEAD@).
 encryptAEAD :: Key -> IV -> Int -> ByteString -> ByteString -> ExceptT CryptoError IO (AuthTag, ByteString)
 encryptAEAD aesKey ivBytes paddedLen ad msg = do
  aead <- initAEAD @AES256 aesKey ivBytes
@@ -1067,10 +1074,7 @@ encryptAEADNoPad aesKey ivBytes ad msg = do

 -- | AEAD-GCM decryption with associated data.
 --
-- Used as part of double ratchet encryption.
-- This function requires 16 bytes IV, it transforms IV in cryptonite_aes_gcm_init here:
-- https://github.com/haskell-crypto/cryptonite/blob/master/cbits/cryptonite_aes.c
-- To make it compatible with WebCrypto we will need to start using initAEADGCM.
+-- Used as part of double ratchet encryption, with a 16-byte IV (see @initAEAD@).
 decryptAEAD :: Key -> IV -> ByteString -> ByteString -> AuthTag -> ExceptT CryptoError IO ByteString
 decryptAEAD aesKey ivBytes ad msg (AuthTag authTag) = do
  aead <- initAEAD @AES256 aesKey ivBytes
@@ -1148,9 +1152,9 @@ maxLength :: forall i. KnownNat i => Int
 maxLength = fromIntegral (natVal $ Proxy @i)
 {-# INLINE maxLength #-}

-- this function requires 16 bytes IV, it transforms IV in cryptonite_aes_gcm_init here:
-- https://github.com/haskell-crypto/cryptonite/blob/master/cbits/cryptonite_aes.c
-- This is used for double ratchet encryption, so to make it compatible with WebCrypto we will need to deprecate it and start using initAEADGCM
+-- The 16-byte double ratchet IV is intentionally not the 96-bit IV recommended by NIST SP 800-38D, so GCM derives J0 = GHASH(IV || 0^64 || [128]_64),
+-- as in crypton_aes_gcm_init: https://hackage.haskell.org/package/crypton-0.34/src/cbits/crypton_aes.c
+-- WebCrypto and other SP 800-38D implementations interoperate only when given all 16 IV bytes.
 initAEAD :: forall c. AES.BlockCipher c => Key -> IV -> ExceptT CryptoError IO (AES.AEAD c)
 initAEAD (Key aesKey) (IV ivBytes) = do
  iv <- makeIV @c ivBytes
@@ -1327,8 +1331,8 @@ sbEncryptNoPad (SbKey key) (CbNonce nonce) = cryptoBox key nonce
 {-# INLINE sbEncryptNoPad #-}

 -- | NaCl @crypto_box@ encrypt with a shared DH secret and 192-bit nonce.
-cbEncryptMaxLenBS :: KnownNat i => DhSecret X25519 -> CbNonce -> MaxLenBS i -> ByteString
-cbEncryptMaxLenBS (DhSecretX25519 secret) (CbNonce nonce) = cryptoBox secret nonce . unMaxLenBS . padMaxLenBS
+cbEncryptMaxLenBS :: (KnownNat i, CbNonceI n) => DhSecret X25519 -> n -> MaxLenBS i -> ByteString
+cbEncryptMaxLenBS (DhSecretX25519 secret) nonce = cryptoBox secret (unCbNonce nonce) . unMaxLenBS . padMaxLenBS
 {-# INLINE cbEncryptMaxLenBS #-}

 cryptoBox :: ByteArrayAccess key => key -> ByteString -> ByteString -> ByteString
@@ -1338,8 +1342,8 @@ cryptoBox secret nonce s = BA.convert tag <> c
    tag = Poly1305.auth rs c

 -- | NaCl @crypto_box@ decrypt with a shared DH secret and 192-bit nonce.
-cbDecrypt :: DhSecret X25519 -> CbNonce -> ByteString -> Either CryptoError ByteString
-cbDecrypt (DhSecretX25519 secret) = sbDecrypt_ secret
+cbDecrypt :: CbNonceI n => DhSecret X25519 -> n -> ByteString -> Either CryptoError ByteString
+cbDecrypt (DhSecretX25519 secret) = sbDecrypt_ secret . toCbNonce
 {-# INLINE cbDecrypt #-}

 -- | NaCl @crypto_box@ decrypt with a shared DH secret and 192-bit nonce (without unpadding).
@@ -1386,9 +1390,16 @@ cbAuthenticate k pk nonce msg = CbAuthenticator $ cbEncryptNoPad (dh' k pk) nonc
 cbVerify :: PublicKeyX25519 -> PrivateKeyX25519 -> CbNonce -> CbAuthenticator -> ByteString -> Bool
 cbVerify k pk nonce (CbAuthenticator s) authorized = cbDecryptNoPad (dh' k pk) nonce s == Right (sha512Hash authorized)

-newtype CbNonce = CryptoBoxNonce {unCbNonce :: ByteString}
+class CbNonceI n where
+  unCbNonce :: n -> ByteString
+
+newtype CbNonce = CryptoBoxNonce ByteString
  deriving (Eq, Show)
-  deriving newtype (FromField)
+
+instance CbNonceI CbNonce where
+  unCbNonce (CryptoBoxNonce s) = s
+
+instance FromField CbNonce where fromField = blobFieldDecoder cbNonce

 instance ToField CbNonce where toField (CryptoBoxNonce s) = toField $ Binary s

@@ -1399,7 +1410,7 @@ pattern CbNonce s <- CryptoBoxNonce s

 instance StrEncoding CbNonce where
  strEncode (CbNonce s) = strEncode s
-  strP = cbNonce <$> strP
+  strP = cbNonce <$?> strP

 instance ToJSON CbNonce where
  toJSON = strToJSON
@@ -1408,13 +1419,16 @@ instance ToJSON CbNonce where
 instance FromJSON CbNonce where
  parseJSON = strParseJSON "CbNonce"

-cbNonce :: ByteString -> CbNonce
+cbNonce :: ByteString -> Either String CbNonce
 cbNonce s
-  | len == 24 = CryptoBoxNonce s
-  | len > 24 = CryptoBoxNonce . fst $ B.splitAt 24 s
-  | otherwise = CryptoBoxNonce $ s <> B.replicate (24 - len) (toEnum 0)
-  where
-    len = B.length s
+  | B.length s == 24 = Right $ CryptoBoxNonce s
+  | otherwise = Left "CbNonce: invalid length"
+
+unsafeCbNonce :: ByteString -> CbNonce
+unsafeCbNonce s = either error id $ cbNonce s
+
+corrCbNonce :: ByteString -> Either String CorrCbNonce
+corrCbNonce s = CorrCbNonce . unCbNonce <$> cbNonce s

 randomCbNonce :: TVar ChaChaDRG -> STM CbNonce
 randomCbNonce = fmap CryptoBoxNonce . randomBytes 24
@@ -1422,13 +1436,30 @@ randomCbNonce = fmap CryptoBoxNonce . randomBytes 24
 randomBytes :: Int -> TVar ChaChaDRG -> STM ByteString
 randomBytes n gVar = stateTVar gVar $ randomBytesGenerate n

-reverseNonce :: CbNonce -> CbNonce
-reverseNonce (CryptoBoxNonce s) = CryptoBoxNonce (B.reverse s)
+reverseNonce :: CbNonceI n => n -> CbNonce
+reverseNonce = CryptoBoxNonce . B.reverse . unCbNonce
+
+xorNonce :: CbNonceI n => ByteString -> n -> CbNonce
+xorNonce s nonce = CryptoBoxNonce $ packZipWith xor s n <> B.drop (B.length s) n
+  where
+    n = unCbNonce nonce
+
+toCbNonce :: CbNonceI n => n -> CbNonce
+toCbNonce = CryptoBoxNonce . unCbNonce

 instance Encoding CbNonce where
  smpEncode = unCbNonce
  smpP = CryptoBoxNonce <$> A.take 24

+newtype CorrCbNonce = CorrCbNonce ByteString
+
+instance CbNonceI CorrCbNonce where
+  unCbNonce (CorrCbNonce s) = s
+
+instance Encoding CorrCbNonce where
+  smpEncode = smpEncode . unCbNonce
+  smpP = corrCbNonce <$?> smpP
+
 newtype SbKey = SecretBoxKey {unSbKey :: ByteString}
  deriving (Eq, Show)
  deriving newtype (FromField)
@@ -72,6 +72,7 @@ module Simplex.Messaging.Crypto.Ratchet
    rcEncryptHeader,
    rcEncryptMsg,
    rcDecrypt,
+    maxSkippedMsgKeys,
    -- used in tests
    MsgHeader (..),
    RatchetInitParams (..),
@@ -119,7 +120,7 @@ import Simplex.Messaging.Crypto.SNTRUP761.Bindings
 import Simplex.Messaging.Encoding
 import Simplex.Messaging.Encoding.String
 import Simplex.Messaging.Parsers (defaultJSON, parseE, parseE')
-import Simplex.Messaging.Util (($>>=), (<$?>))
+import Simplex.Messaging.Util ((<$?>))
 import Simplex.Messaging.Version
 import Simplex.Messaging.Version.Internal
 import UnliftIO.STM
@@ -327,9 +328,13 @@ instance StrEncoding AnyE2ERatchetParamsUri where
            Nothing -> pure $ AnyE2ERatchetParamsUri SRKSProposed a $ E2ERatchetParamsUri vr k1 k2 Nothing
      _ -> fail "bad e2e params"
    where
-      kemP query =
-        queryParam_ "kem_key" query
-          $>>= \k -> Just . kemParams k <$> queryParam_ "kem_ct" query
+      kemP query = do
+        k_ <- queryParam_ "kem_key" query
+        ct_ <- queryParam_ "kem_ct" query
+        case (k_, ct_) of
+          (Just k, _) -> pure $ Just $ kemParams k ct_
+          (Nothing, Nothing) -> pure Nothing
+          (Nothing, Just _) -> fail "bad e2e params: kem_ct without kem_key"
      kemParams k = \case
        Nothing -> ARKP SRKSProposed $ RKParamsProposed k
        Just ct -> ARKP SRKSAccepted $ RKParamsAccepted ct k
@@ -958,6 +963,9 @@ type DecryptResult a = (Either CryptoError ByteString, Ratchet a, SkippedMsgDiff
 maxSkip :: Word32
 maxSkip = 512

+maxSkippedMsgKeys :: Int
+maxSkippedMsgKeys = 2000
+
 rcDecrypt ::
  forall a.
  (AlgorithmI a, DhAlgorithm a) =>
@@ -16,6 +16,8 @@ module Simplex.Messaging.Crypto.SNTRUP761.Bindings
  ) where

 import Control.Concurrent.STM
+import Control.Exception (throwIO)
+import Control.Monad (when)
 import Crypto.Random (ChaChaDRG)
 import Data.Aeson (FromJSON (..), ToJSON (..))
 import Data.Bifunctor (bimap)
@@ -23,6 +25,7 @@ import Data.ByteArray (ScrubbedBytes)
 import qualified Data.ByteArray as BA
 import Data.ByteString (ByteString)
 import Simplex.Messaging.Agent.Store.DB (FromField (..), ToField (..))
+import qualified Simplex.Messaging.Crypto as C
 import Simplex.Messaging.Crypto.SNTRUP761.Bindings.Defines
 import Simplex.Messaging.Crypto.SNTRUP761.Bindings.FFI
 import Simplex.Messaging.Crypto.SNTRUP761.Bindings.RNG (rngFuncPtr, withDRG)
@@ -55,14 +58,13 @@ pattern KEMSharedKey s <- KEMSharedKey_ s
 type KEMKeyPair = (KEMPublicKey, KEMSecretKey)

 sntrup761Keypair :: TVar ChaChaDRG -> IO KEMKeyPair
-sntrup761Keypair drg =
-  bimap KEMPublicKey_ KEMSecretKey
-    <$> BA.allocRet
-      c_SNTRUP761_SECRETKEY_SIZE
-      ( \skPtr ->
-          BA.alloc c_SNTRUP761_PUBLICKEY_SIZE $ \pkPtr ->
-            withDRG drg $ \cxtPtr -> c_sntrup761_keypair pkPtr skPtr cxtPtr rngFuncPtr
-      )
+sntrup761Keypair drg = do
+  ((r, pk), sk) <-
+    BA.allocRet c_SNTRUP761_SECRETKEY_SIZE $ \skPtr ->
+      BA.allocRet c_SNTRUP761_PUBLICKEY_SIZE $ \pkPtr ->
+        withDRG drg $ \cxtPtr -> c_sntrup761_keypair pkPtr skPtr cxtPtr rngFuncPtr
+  when (r /= 0) $ throwIO C.CryptoKEMKeyGenError
+  pure (KEMPublicKey_ pk, KEMSecretKey sk)

 sntrup761Enc :: TVar ChaChaDRG -> KEMPublicKey -> IO (KEMCiphertext, KEMSharedKey)
 sntrup761Enc drg (KEMPublicKey pk) =
@@ -10,9 +10,9 @@ import Foreign
 import Foreign.C
 import Simplex.Messaging.Crypto.SNTRUP761.Bindings.RNG (RNGContext, RNGFunc)

-- void sntrup761_keypair (uint8_t *pk, uint8_t *sk, void *random_ctx, sntrup761_random_func *random);
+-- int sntrup761_keypair (uint8_t *pk, uint8_t *sk, void *random_ctx, sntrup761_random_func *random);
 foreign import ccall "sntrup761_keypair"
-  c_sntrup761_keypair :: Ptr Word8 -> Ptr Word8 -> Ptr RNGContext -> FunPtr RNGFunc -> IO ()
+  c_sntrup761_keypair :: Ptr Word8 -> Ptr Word8 -> Ptr RNGContext -> FunPtr RNGFunc -> IO CInt

 -- void sntrup761_enc (uint8_t *c, uint8_t *k, const uint8_t *pk, void *random_ctx, sntrup761_random_func *random);
 foreign import ccall "sntrup761_enc"
@@ -17,6 +17,7 @@ module Simplex.Messaging.Crypto.ShortLink
    encodeSignUserData,
    newOwnerAuth,
    encryptLinkData,
+    encryptFixedData,
    encryptUserData,
    decryptLinkData,
  )
@@ -84,9 +85,10 @@ newOwnerAuth g ownerId signingKey = do
  pure (ownerPrivKey, OwnerAuth {ownerId, ownerKey, authOwnerSig})

 encryptLinkData :: TVar ChaChaDRG -> C.SbKey -> (ByteString, ByteString) -> ExceptT AgentErrorType IO QueueLinkData
-encryptLinkData g k = bimapM (encrypt fixedDataPaddedLength) (encrypt userDataPaddedLength)
-  where
-    encrypt len = encryptData g k len
+encryptLinkData g k = bimapM (encryptFixedData g k) (encryptUserData g k)
+
+encryptFixedData :: TVar ChaChaDRG -> C.SbKey -> ByteString -> ExceptT AgentErrorType IO EncDataBytes
+encryptFixedData g k s = encryptData g k fixedDataPaddedLength s

 encryptUserData :: TVar ChaChaDRG -> C.SbKey -> ByteString -> ExceptT AgentErrorType IO EncDataBytes
 encryptUserData g k s = encryptData g k userDataPaddedLength s
@@ -72,7 +72,6 @@ import Simplex.Messaging.Notifications.Transport
 import Simplex.Messaging.Protocol (EntityId (..), ErrorType (..), NotifierId, Party (..), ProtocolServer (host), SMPServer, ServiceSub (..), SignedTransmission, Transmission, pattern NoEntity, pattern SMPServer, encodeTransmission, tGetServer, tPut)
 import qualified Simplex.Messaging.Protocol as SMP
 import Simplex.Messaging.Server
-import Simplex.Messaging.Server.AddressStats (AddrStats, ServerAddrStats (..), addressStatsThread, incAddrCounter, printTopAddresses, withAddrStats)
 import Simplex.Messaging.Server.Control (CPClientRole (..))
 import Simplex.Messaging.Server.Env.STM (StartOptions (..))
 import Simplex.Messaging.Server.Stats (PeriodStats (..), PeriodStatCounts (..), periodStatCounts, periodStatDataCounts, updatePeriodStats)
@@ -81,7 +80,7 @@ import Simplex.Messaging.SystemTime
 import Simplex.Messaging.TMap (TMap)
 import Simplex.Messaging.Transport (ASrvTransport, ATransport (..), THandle (..), THandleAuth (..), THandleParams (..), TProxy, Transport (..), TransportPeer (..), defaultSupportedParams)
 import Simplex.Messaging.Transport.Buffer (trimCR)
-import Simplex.Messaging.Transport.Server (AddHTTP, TLSServerCredential (..), newSocketState, runLocalTCPServer, runTransportServerState_)
+import Simplex.Messaging.Transport.Server (AddHTTP, runTransportServer, runLocalTCPServer)
 import Simplex.Messaging.Util
 import System.Environment (lookupEnv)
 import System.Exit (exitFailure, exitSuccess)
@@ -123,7 +122,6 @@ ntfServer cfg@NtfServerConfig {transports, transportConfig = tCfg, startOptions}
        : map runServer transports
          <> serverStatsThread_ cfg
          <> prometheusMetricsThread_ cfg
-          <> addressStatsThread_ cfg
          <> controlPortThread_ cfg
    )
    `finally` stopServer
@@ -133,20 +131,16 @@ ntfServer cfg@NtfServerConfig {transports, transportConfig = tCfg, startOptions}
      srvCreds <- asks tlsServerCreds
      serverSignKey <- either fail pure $ C.x509ToPrivate' $ snd srvCreds
      env <- ask
-      ss <- liftIO newSocketState
-      liftIO $ runTransportServerState_ ss started tcpPort defaultSupportedParams TLSServerCredential {credential = srvCreds, sniCredential = Nothing} tCfg $ \sock (_, h) ->
-        runClient serverSignKey t sock h `runReaderT` env
+      liftIO $ runTransportServer started tcpPort defaultSupportedParams srvCreds tCfg $ \h -> runClient serverSignKey t h `runReaderT` env

-    runClient :: Transport c => C.APrivateSignKey -> TProxy c 'TServer -> Socket -> c 'TServer -> M ()
-    runClient signKey _ sock h = do
-      stats_ <- asks addrStats
-      withAddrStats (addrStatsMap <$> stats_) sock $ \addrStats_ -> do
-        kh <- asks serverIdentity
-        ks <- atomically . C.generateKeyPair =<< asks random
-        NtfServerConfig {ntfServerVRange} <- asks config
-        liftIO (runExceptT $ ntfServerHandshake signKey h ks kh ntfServerVRange) >>= \case
-          Right th -> runNtfClientTransport addrStats_ th
-          Left _ -> pure ()
+    runClient :: Transport c => C.APrivateSignKey -> TProxy c 'TServer -> c 'TServer -> M ()
+    runClient signKey _ h = do
+      kh <- asks serverIdentity
+      ks <- atomically . C.generateKeyPair =<< asks random
+      NtfServerConfig {ntfServerVRange} <- asks config
+      liftIO (runExceptT $ ntfServerHandshake signKey h ks kh ntfServerVRange) >>= \case
+        Right th -> runNtfClientTransport th
+        Left _ -> pure ()

    stopServer :: M ()
    stopServer = do
@@ -237,10 +231,6 @@ ntfServer cfg@NtfServerConfig {transports, transportConfig = tCfg, startOptions}
      [savePrometheusMetrics interval prometheusMetricsFile]
    prometheusMetricsThread_ _ = []

-    addressStatsThread_ :: NtfServerConfig -> [M ()]
-    addressStatsThread_ NtfServerConfig {addressStats = Just statsCfg} = [asks addrStats >>= mapM_ (liftIO . addressStatsThread statsCfg)]
-    addressStatsThread_ _ = []
-
    savePrometheusMetrics :: Int -> FilePath -> M ()
    savePrometheusMetrics saveInterval metricsFile = do
      labelMyThread "savePrometheusMetrics"
@@ -266,7 +256,7 @@ ntfServer cfg@NtfServerConfig {transports, transportConfig = tCfg, startOptions}
      pure NtfServerMetrics {statsData = d, activeTokensCounts = psTkns, activeSubsCounts = psSubs, tokenCount, approxSubCount, lastNtfCount, rtsOptions}

    getNtfRealTimeMetrics :: NtfEnv -> IO NtfRealTimeMetrics
-    getNtfRealTimeMetrics NtfEnv {subscriber, pushServer, addrStats} = do
+    getNtfRealTimeMetrics NtfEnv {subscriber, pushServer} = do
 #if MIN_VERSION_base(4,18,0)
      threadsCount <- length <$> listThreads
 #else
@@ -284,7 +274,6 @@ ntfServer cfg@NtfServerConfig {transports, transportConfig = tCfg, startOptions}
      ntfPendingQueueSubs <- getSMPSubMetrics a pendingQueueSubs
      smpSessionCount <- M.size <$> readTVarIO smpSessions
      apnsPushQLength <- pushWorkersQLength pushWorkers
-      addressHistograms <- mapM (readIORef . addrHistograms) addrStats
      pure
        NtfRealTimeMetrics
          { threadsCount,
@@ -296,8 +285,7 @@ ntfServer cfg@NtfServerConfig {transports, transportConfig = tCfg, startOptions}
            ntfPendingServiceSubs,
            ntfPendingQueueSubs,
            smpSessionCount,
-            apnsPushQLength,
-            addressHistograms
+            apnsPushQLength
          }
      where
        getSMPServiceSubMetrics :: forall sub. SMPClientAgent 'NotifierService -> (SMPClientAgent 'NotifierService -> TMap SMPServer (TVar (Maybe sub))) -> (sub -> Int64) -> IO NtfSMPSubMetrics
@@ -453,10 +441,7 @@ ntfServer cfg@NtfServerConfig {transports, transportConfig = tCfg, startOptions}
                      T.hPutStrLn h $ name <> " own servers count: " <> tshow (length ownServers)
                      when (r == CPRAdmin) $ T.hPutStrLn h $ name <> " own servers: " <> T.intercalate "," ownServers
                      T.hPutStrLn h $ name <> " other servers count: " <> tshow otherServers
-              CPAddresses name n_ -> withUserRole $ do
-                stats_ <- unliftIO u $ asks addrStats
-                printTopAddresses h (addrStatsMap <$> stats_) name n_
-              CPHelp -> hPutStrLn h "commands: stats, stats-rts, server-info, addresses, help, quit"
+              CPHelp -> hPutStrLn h "commands: stats, stats-rts, server-info, help, quit"
              CPQuit -> pure ()
              CPSkip -> pure ()
              where
@@ -771,11 +756,11 @@ periodicNtfsThread s = do
    cnt <- withPeriodicNtfTokens st now $ \tkn -> unlift $ pushNotification s Nothing False tkn PNCheckMessages
    logNote $ "Scheduled periodic notifications: " <> tshow cnt

-runNtfClientTransport :: Transport c => Maybe (AddrStats NtfAddrCounter) -> THandleNTF c 'TServer -> M ()
-runNtfClientTransport addrStats_ th@THandle {params} = do
+runNtfClientTransport :: Transport c => THandleNTF c 'TServer -> M ()
+runNtfClientTransport th@THandle {params} = do
  qSize <- asks $ clientQSize . config
  ts <- liftIO getSystemTime
-  c <- liftIO $ newNtfServerClient qSize params ts addrStats_
+  c <- liftIO $ newNtfServerClient qSize params ts
  s <- asks subscriber
  ps <- asks pushServer
  expCfg <- asks $ inactiveClientExpiration . config
@@ -790,7 +775,7 @@ clientDisconnected :: NtfServerClient -> IO ()
 clientDisconnected NtfServerClient {connected} = atomically $ writeTVar connected False

 receive :: Transport c => NtfPostgresStore -> THandleNTF c 'TServer -> NtfServerClient -> IO ()
-receive st th@THandle {params = THandleParams {thAuth}} NtfServerClient {rcvQ, sndQ, rcvActiveAt, ntfClientAddrStats} = forever $ do
+receive st th@THandle {params = THandleParams {thAuth}} NtfServerClient {rcvQ, sndQ, rcvActiveAt} = forever $ do
  ts <- L.toList <$> tGetServer th
  atomically . (writeTVar rcvActiveAt $!) =<< getSystemTime
  (errs, cmds) <- partitionEithers <$> mapM cmdAction ts
@@ -799,21 +784,17 @@ receive st th@THandle {params = THandleParams {thAuth}} NtfServerClient {rcvQ, s
  where
    cmdAction = \case
      Left (corrId, entId, e) -> do
-        incAddrStats NACErrors
        logError $ "invalid client request: " <> tshow e
        pure $ Left (corrId, entId, NRErr e)
-      Right t@(_, _, (corrId, entId, cmd)) -> do
-        incAddrStats $ ntfCmdCounter cmd
+      Right t@(_, _, (corrId, entId, _)) ->
        verified =<< verifyNtfTransmission st thAuth t
        where
          verified = \case
            VRVerified req -> pure $ Right req
            VRFailed e -> do
-              incAddrStats NACErrors
              logError "unauthorized client request"
              pure $ Left (corrId, entId, NRErr e)
    write q = mapM_ (atomically . writeTBQueue q) . L.nonEmpty
-    incAddrStats c = forM_ ntfClientAddrStats (`incAddrCounter` c)

 send :: Transport c => THandleNTF c 'TServer -> NtfServerClient -> IO ()
 send h@THandle {params} NtfServerClient {sndQ, sndActiveAt} = forever $ do
@@ -7,17 +7,14 @@ module Simplex.Messaging.Notifications.Server.Control
 where

 import qualified Data.Attoparsec.ByteString.Char8 as A
-import Data.Text (Text)
 import Simplex.Messaging.Encoding.String
 import Simplex.Messaging.Protocol (BasicAuth)
-import Simplex.Messaging.Server.AddressStats (addressesArgs, addressesArgsP)

 data ControlProtocol
  = CPAuth BasicAuth
  | CPStats
  | CPStatsRTS
  | CPServerInfo
-  | CPAddresses Text (Maybe Int)
  | CPHelp
  | CPQuit
  | CPSkip
@@ -28,7 +25,6 @@ instance StrEncoding ControlProtocol where
    CPStats -> "stats"
    CPStatsRTS -> "stats-rts"
    CPServerInfo -> "server-info"
-    CPAddresses name n_ -> "addresses " <> addressesArgs name n_
    CPHelp -> "help"
    CPQuit -> "quit"
    CPSkip -> ""
@@ -38,7 +34,6 @@ instance StrEncoding ControlProtocol where
      "stats" -> pure CPStats
      "stats-rts" -> pure CPStatsRTS
      "server-info" -> pure CPServerInfo
-      "addresses" -> uncurry CPAddresses <$> addressesArgsP
      "help" -> pure CPHelp
      "quit" -> pure CPQuit
      "" -> pure CPSkip
@@ -19,8 +19,6 @@ module Simplex.Messaging.Notifications.Server.Env
    PushWorkerVar,
    NtfRequest (..),
    NtfServerClient (..),
-    NtfAddrCounter (..),
-    ntfCmdCounter,
    defaultInactiveClientExpiration,
    newNtfServerEnv,
    newNtfSubscriber,
@@ -57,7 +55,6 @@ import Simplex.Messaging.Notifications.Server.Store.Postgres
 import Simplex.Messaging.Notifications.Server.Store.Types
 import Simplex.Messaging.Notifications.Transport (NTFVersion, VersionRangeNTF)
 import Simplex.Messaging.Protocol (BasicAuth, CorrId, Party (..), SMPServer, SParty (..), ServiceId, Transmission)
-import Simplex.Messaging.Server.AddressStats (AddrCounter (..), AddrStats, AddressStatsConfig, ServerAddrStats, newServerAddrStats)
 import Simplex.Messaging.Server.Env.STM (StartOptions (..))
 import Simplex.Messaging.Server.Expiration
 import Simplex.Messaging.Server.QueueStore.Postgres.Config (PostgresStoreCfg (..))
@@ -100,7 +97,6 @@ data NtfServerConfig = NtfServerConfig
    -- | interval and file to save prometheus metrics
    prometheusInterval :: Maybe Int,
    prometheusMetricsFile :: FilePath,
-    addressStats :: Maybe AddressStatsConfig,
    ntfServerVRange :: VersionRangeNTF,
    transportConfig :: TransportServerConfig,
    startOptions :: StartOptions
@@ -121,56 +117,11 @@ data NtfEnv = NtfEnv
    random :: TVar ChaChaDRG,
    tlsServerCreds :: TLS.Credential,
    serverIdentity :: C.KeyHash,
-    serverStats :: NtfServerStats,
-    addrStats :: Maybe (ServerAddrStats NtfAddrCounter)
+    serverStats :: NtfServerStats
  }

-data NtfAddrCounter
-  = NACConnections
-  | NACErrors
-  | NACTNew
-  | NACTVfy
-  | NACTChk
-  | NACTRpl
-  | NACTDel
-  | NACTCrn
-  | NACSNew
-  | NACSChk
-  | NACSDel
-  | NACPing
-  deriving (Eq, Ord, Enum, Bounded, Show)
-
-instance AddrCounter NtfAddrCounter where
-  counterName = \case
-    NACConnections -> "connections"
-    NACErrors -> "errors"
-    NACTNew -> "TNEW"
-    NACTVfy -> "TVFY"
-    NACTChk -> "TCHK"
-    NACTRpl -> "TRPL"
-    NACTDel -> "TDEL"
-    NACTCrn -> "TCRN"
-    NACSNew -> "SNEW"
-    NACSChk -> "SCHK"
-    NACSDel -> "SDEL"
-    NACPing -> "PING"
-  connectionsCounter = NACConnections
-
-ntfCmdCounter :: NtfCmd -> NtfAddrCounter
-ntfCmdCounter (NtfCmd _ cmd) = case cmd of
-  TNEW _ -> NACTNew
-  TVFY _ -> NACTVfy
-  TCHK -> NACTChk
-  TRPL _ -> NACTRpl
-  TDEL -> NACTDel
-  TCRN _ -> NACTCrn
-  SNEW _ -> NACSNew
-  SCHK -> NACSChk
-  SDEL -> NACSDel
-  PING -> NACPing
-
 newNtfServerEnv :: NtfServerConfig -> IO NtfEnv
-newNtfServerEnv config@NtfServerConfig {pushQSize, smpAgentCfg, apnsConfig, dbStoreConfig, ntfCredentials, useServiceCreds, addressStats} = do
+newNtfServerEnv config@NtfServerConfig {pushQSize, smpAgentCfg, apnsConfig, dbStoreConfig, ntfCredentials, useServiceCreds} = do
  random <- C.newRandom
  store <- newNtfDbStore dbStoreConfig
  tlsServerCreds <- loadServerCredential ntfCredentials
@@ -179,8 +130,7 @@ newNtfServerEnv config@NtfServerConfig {pushQSize, smpAgentCfg, apnsConfig, dbSt
  subscriber <- newNtfSubscriber smpAgentCfg dbService random
  pushServer <- newNtfPushServer pushQSize apnsConfig
  serverStats <- newNtfServerStats =<< getCurrentTime
-  addrStats <- mapM (const newServerAddrStats) addressStats
-  pure NtfEnv {config, subscriber, pushServer, store, random, tlsServerCreds, serverIdentity = C.KeyHash fp, serverStats, addrStats}
+  pure NtfEnv {config, subscriber, pushServer, store, random, tlsServerCreds, serverIdentity = C.KeyHash fp, serverStats}
  where
    mkDbService g st = DBService {getCredentials, updateServiceId}
      where
@@ -292,15 +242,14 @@ data NtfServerClient = NtfServerClient
    ntfThParams :: THandleParams NTFVersion 'TServer,
    connected :: TVar Bool,
    rcvActiveAt :: TVar SystemTime,
-    sndActiveAt :: TVar SystemTime,
-    ntfClientAddrStats :: Maybe (AddrStats NtfAddrCounter)
+    sndActiveAt :: TVar SystemTime
  }

-newNtfServerClient :: Natural -> THandleParams NTFVersion 'TServer -> SystemTime -> Maybe (AddrStats NtfAddrCounter) -> IO NtfServerClient
-newNtfServerClient qSize ntfThParams ts ntfClientAddrStats = do
+newNtfServerClient :: Natural -> THandleParams NTFVersion 'TServer -> SystemTime -> IO NtfServerClient
+newNtfServerClient qSize ntfThParams ts = do
  rcvQ <- newTBQueueIO qSize
  sndQ <- newTBQueueIO qSize
  connected <- newTVarIO True
  rcvActiveAt <- newTVarIO ts
  sndActiveAt <- newTVarIO ts
-  return NtfServerClient {rcvQ, sndQ, ntfThParams, connected, rcvActiveAt, sndActiveAt, ntfClientAddrStats}
+  return NtfServerClient {rcvQ, sndQ, ntfThParams, connected, rcvActiveAt, sndActiveAt}
@@ -141,8 +141,6 @@ ntfServerCLI cfgPath logPath =
               \disconnect = off\n"
            <> ("# ttl = " <> tshow (ttl defaultInactiveClientExpiration) <> "\n")
            <> ("# check_interval = " <> tshow (checkInterval defaultInactiveClientExpiration) <> "\n")
-            <> "\n"
-            <> addressStatsIniContent
    enableStoreLog' = settingIsOn "STORE_LOG" "enable"
    runServer startOptions ini = do
      setLogLevel $ logLevel startOptions
@@ -218,7 +216,6 @@ ntfServerCLI cfgPath logPath =
              serverStatsBackupFile = logStats $> combine logPath "ntf-server-stats.log",
              prometheusInterval = eitherToMaybe $ read . T.unpack <$> lookupValue "STORE_LOG" "prometheus_interval" ini,
              prometheusMetricsFile = combine logPath "ntf-server-metrics.txt",
-              addressStats = iniAddressStats ini,
              ntfServerVRange = supportedServerNTFVRange,
              transportConfig =
                mkTransportServerConfig
@@ -21,9 +21,7 @@ import Data.Time.Clock (UTCTime (..), diffUTCTime)
 import Data.Time.Clock.System (systemEpochDay)
 import Data.Time.Format.ISO8601 (iso8601Show)
 import Numeric.Natural (Natural)
-import Simplex.Messaging.Notifications.Server.Env (NtfAddrCounter)
 import Simplex.Messaging.Notifications.Server.Stats
-import Simplex.Messaging.Server.AddressStats (AddrHistogram, addrHistogramMetrics)
 import Simplex.Messaging.Server.Stats (PeriodStatCounts (..))
 import Simplex.Messaging.Transport (simplexMQVersion)
 import Simplex.Messaging.Util (tshow)
@@ -51,8 +49,7 @@ data NtfRealTimeMetrics = NtfRealTimeMetrics
    ntfPendingServiceSubs :: NtfSMPSubMetrics,
    ntfPendingQueueSubs :: NtfSMPSubMetrics,
    smpSessionCount :: Int,
-    apnsPushQLength :: Natural,
-    addressHistograms :: Maybe (M.Map NtfAddrCounter AddrHistogram)
+    apnsPushQLength :: Natural
  }

 data NtfSMPWorkerMetrics = NtfSMPWorkerMetrics {ownServers :: [Text], otherServers :: Int}
@@ -62,7 +59,7 @@ data NtfSMPSubMetrics = NtfSMPSubMetrics {ownSrvSubs :: M.Map Text Int, otherSer
 {-# FOURMOLU_DISABLE\n#-}
 ntfPrometheusMetrics :: NtfServerMetrics -> NtfRealTimeMetrics -> UTCTime -> Text
 ntfPrometheusMetrics sm rtm ts =
-  time <> tokens <> subscriptions <> notifications <> clientAddresses <> info
+  time <> tokens <> subscriptions <> notifications <> info
  where
    NtfServerMetrics {statsData, activeTokensCounts = psTkns, activeSubsCounts = psSubs, tokenCount, approxSubCount, lastNtfCount, rtsOptions} = sm
    NtfRealTimeMetrics
@@ -75,8 +72,7 @@ ntfPrometheusMetrics sm rtm ts =
        ntfPendingServiceSubs,
        ntfPendingQueueSubs,
        smpSessionCount,
-        apnsPushQLength,
-        addressHistograms
+        apnsPushQLength
      } = rtm
    NtfServerStatsData
      { _fromTime,
@@ -225,7 +221,6 @@ ntfPrometheusMetrics sm rtm ts =
      <> showNtfsByServer _ntfReceivedAuthOwn "simplex_ntf_notifications_received_auth_own" "Received notifications without token or subscription (AUTH error)" "ntfReceivedAuthOwn"
      <> showNtfsByServer _ntfDeliveredOwn "simplex_ntf_notifications_delivered_own" "Delivered notifications" "ntfDeliveredOwn"
      <> showNtfsByServer _ntfFailedOwn "simplex_ntf_notifications_failed_own" "Failed notifications" "ntfFailedOwn"
-    clientAddresses = maybe "" (addrHistogramMetrics "simplex_ntf" tsEpoch) addressHistograms
    info =
      "# Info\n\
      \# ----\n\
@@ -1,5 +1,6 @@


+
 SET statement_timeout = 0;
 SET lock_timeout = 0;
 SET idle_in_transaction_session_timeout = 0;
@@ -312,3 +313,4 @@ ALTER TABLE ONLY ntf_server.subscriptions



+
@@ -14,19 +14,16 @@ module Simplex.Messaging.Notifications.Transport
    THandleNTF,
    supportedClientNTFVRange,
    supportedServerNTFVRange,
-    entitlementNTFVersion,
    alpnSupportedNTFHandshakes,
    ntfServerHandshake,
    ntfClientHandshake,
  ) where

 import Control.Monad.Except
-import Control.Monad.IO.Class (liftIO)
 import Control.Monad.Trans.Except
 import Data.Word (Word16)
 import qualified Data.X509 as X
 import qualified Simplex.Messaging.Crypto as C
-import Simplex.Messaging.Crypto.Entitlement (EntitlementProof)
 import Simplex.Messaging.Encoding
 import Simplex.Messaging.Transport
 import Simplex.Messaging.Util (liftEitherWith)
@@ -53,14 +50,11 @@ initialNTFVersion = VersionNTF 3
 _invalidReasonNTFVersion :: VersionNTF
 _invalidReasonNTFVersion = VersionNTF 3

-entitlementNTFVersion :: VersionNTF
-entitlementNTFVersion = VersionNTF 4
-
 currentClientNTFVersion :: VersionNTF
-currentClientNTFVersion = VersionNTF 4
+currentClientNTFVersion = VersionNTF 3

 currentServerNTFVersion :: VersionNTF
-currentServerNTFVersion = VersionNTF 4
+currentServerNTFVersion = VersionNTF 3

 supportedClientNTFVRange :: VersionRangeNTF
 supportedClientNTFVRange = mkVersionRange initialNTFVersion currentClientNTFVersion
@@ -84,9 +78,7 @@ data NtfClientHandshake = NtfClientHandshake
  { -- | agreed SMP notifications server protocol version
    ntfVersion :: VersionNTF,
    -- | server identity - CA certificate fingerprint
-    keyHash :: C.KeyHash,
-    -- | proof of the user entitlement bound to the session
-    entitlementProof :: Maybe EntitlementProof
+    keyHash :: C.KeyHash
  }

 instance Encoding NtfServerHandshake where
@@ -99,15 +91,11 @@ instance Encoding NtfServerHandshake where
    pure NtfServerHandshake {ntfVersionRange, sessionId, authPubKey}

 instance Encoding NtfClientHandshake where
-  smpEncode NtfClientHandshake {ntfVersion = v, keyHash, entitlementProof} =
-    smpEncode (v, keyHash) <> ifHasEntitlement v (smpEncode entitlementProof) ""
+  smpEncode NtfClientHandshake {ntfVersion, keyHash} =
+    smpEncode (ntfVersion, keyHash)
  smpP = do
-    (v, keyHash) <- smpP
-    entitlementProof <- ifHasEntitlement v smpP (pure Nothing)
-    pure NtfClientHandshake {ntfVersion = v, keyHash, entitlementProof}
-
-ifHasEntitlement :: VersionNTF -> a -> a -> a
-ifHasEntitlement v a b = if v >= entitlementNTFVersion then a else b
+    (ntfVersion, keyHash) <- smpP
+    pure NtfClientHandshake {ntfVersion, keyHash}

 -- | Notifcations server transport handshake.
 ntfServerHandshake :: forall c. Transport c => C.APrivateSignKey -> c 'TServer -> C.KeyPairX25519 -> C.KeyHash -> VersionRangeNTF -> ExceptT TransportError IO (THandleNTF c 'TServer)
@@ -125,8 +113,8 @@ ntfServerHandshake serverSignKey c (k, pk) kh ntfVersionRange = do
            Nothing -> throwE TEVersion

 -- | Notifcations server client transport handshake.
-ntfClientHandshake :: forall c. Transport c => c 'TClient -> C.KeyHash -> VersionRangeNTF -> Bool -> Maybe (ServiceCredentials, C.KeyPairEd25519) -> (SessionId -> IO (Maybe EntitlementProof)) -> ExceptT TransportError IO (THandleNTF c 'TClient)
-ntfClientHandshake c keyHash ntfVRange _proxyServer _serviceKeys mkEntitlementProof = do
+ntfClientHandshake :: forall c. Transport c => c 'TClient -> C.KeyHash -> VersionRangeNTF -> Bool -> Maybe (ServiceCredentials, C.KeyPairEd25519) -> ExceptT TransportError IO (THandleNTF c 'TClient)
+ntfClientHandshake c keyHash ntfVRange _proxyServer _serviceKeys = do
  let th@THandle {params = THandleParams {sessionId}} = ntfTHandle c
  NtfServerHandshake {sessionId = sessId, ntfVersionRange, authPubKey} <- getHandshake th
  if sessionId /= sessId
@@ -138,8 +126,7 @@ ntfClientHandshake c keyHash ntfVRange _proxyServer _serviceKeys mkEntitlementPr
          pubKey <- C.verifyX509 serverKey authPubKey
          (,CertChainPubKey (getPeerCertChain c) authPubKey) <$> C.x509ToPublic' pubKey
        let v = maxVersion vr
-        ep <- if v >= entitlementNTFVersion then liftIO (mkEntitlementProof sessionId) else pure Nothing
-        sendHandshake th $ NtfClientHandshake {ntfVersion = v, keyHash, entitlementProof = ep}
+        sendHandshake th $ NtfClientHandshake {ntfVersion = v, keyHash}
        pure $ ntfThHandleClient th v vr ck
      Nothing -> throwE TEVersion

@@ -145,7 +145,10 @@ module Simplex.Messaging.Protocol
    RcvNtfDhSecret,
    Message (..),
    RcvMessage (..),
-    MsgId,
+    MsgId (unMsgId),
+    mkMsgId,
+    unsafeMsgId,
+    randomMsgId,
    MsgBody,
    IdsHash (..),
    ServiceSub (..),
@@ -168,6 +171,7 @@ module Simplex.Messaging.Protocol
    EncFwdTransmission (..),
    EncResponse (..),
    EncTransmission (..),
+    encTransmissionNonce,
    FwdResponse (..),
    FwdTransmission (..),
    NameRecord (..),
@@ -232,8 +236,10 @@ module Simplex.Messaging.Protocol
 where

 import Control.Applicative (optional, (<|>))
+import Control.Concurrent.STM (STM, TVar)
 import Control.Exception (Exception, SomeException, displayException, fromException)
 import Control.Monad.Except
+import Crypto.Random (ChaChaDRG)
 import Data.Aeson (FromJSON (..), ToJSON (..))
 import qualified Data.Aeson as J
 import qualified Data.Aeson.TH as J
@@ -241,6 +247,7 @@ import Data.Attoparsec.ByteString.Char8 (Parser, (<?>))
 import qualified Data.Attoparsec.ByteString.Char8 as A
 import Data.Bifunctor (bimap, first)
 import Data.Bits (xor)
+import qualified Data.ByteArray as BA
 import qualified Data.ByteString as BS
 import qualified Data.ByteString.Base64 as B64
 import Data.ByteString.Char8 (ByteString)
@@ -267,9 +274,8 @@ import qualified GHC.TypeLits as TE
 import qualified GHC.TypeLits as Type
 import Network.Socket (ServiceName)
 import qualified Network.TLS as TLS
-import Simplex.Messaging.Agent.Store.DB (Binary (..), FromField (..), ToField (..))
+import Simplex.Messaging.Agent.Store.DB (Binary (..), FromField (..), ToField (..), blobFieldDecoder)
 import qualified Simplex.Messaging.Crypto as C
-import Simplex.Messaging.Crypto.Entitlement (EntitlementProof)
 import Simplex.Messaging.Encoding
 import Simplex.Messaging.Encoding.String
 import Simplex.Messaging.Names.Record
@@ -702,19 +708,24 @@ instance Encoding NewNtfCreds where
 newtype EncTransmission = EncTransmission ByteString
  deriving (Show)

+encTransmissionNonce :: C.CbNonceI n => VersionSMP -> n -> C.CbNonce
+encTransmissionNonce v nonce
+  | v >= fwdNoncesSMPVersion = C.xorNonce (smpEncode v) nonce
+  | otherwise = C.toCbNonce nonce
+
 data FwdTransmission = FwdTransmission
-  { fwdCorrId :: CorrId,
+  { fwdCorrId :: C.CorrCbNonce,
    fwdVersion :: VersionSMP,
    fwdKey :: C.PublicKeyX25519,
    fwdTransmission :: EncTransmission
  }

 instance Encoding FwdTransmission where
-  smpEncode FwdTransmission {fwdCorrId = CorrId corrId, fwdVersion, fwdKey, fwdTransmission = EncTransmission t} =
-    smpEncode (corrId, fwdVersion, fwdKey, Tail t)
+  smpEncode FwdTransmission {fwdCorrId, fwdVersion, fwdKey, fwdTransmission = EncTransmission t} =
+    smpEncode (fwdCorrId, fwdVersion, fwdKey, Tail t)
  smpP = do
-    (corrId, fwdVersion, fwdKey, Tail t) <- smpP
-    pure FwdTransmission {fwdCorrId = CorrId corrId, fwdVersion, fwdKey, fwdTransmission = EncTransmission t}
+    (fwdCorrId, fwdVersion, fwdKey, Tail t) <- smpP
+    pure FwdTransmission {fwdCorrId, fwdVersion, fwdKey, fwdTransmission = EncTransmission t}

 newtype EncFwdTransmission = EncFwdTransmission ByteString
  deriving (Show)
@@ -737,8 +748,8 @@ data BrokerMsg where
  NMSG :: C.CbNonce -> EncNMsgMeta -> BrokerMsg
  -- Should include certificate chain
  PKEY :: SessionId -> VersionRangeSMP -> CertChainPubKey -> BrokerMsg -- TLS-signed server key for proxy shared secret and initial sender key
-  RRES :: EncFwdResponse -> BrokerMsg -- relay to proxy
-  PRES :: EncResponse -> BrokerMsg -- proxy to client
+  RRES :: Maybe C.CbNonce -> EncFwdResponse -> BrokerMsg -- relay to proxy
+  PRES :: Maybe C.CbNonce -> EncResponse -> BrokerMsg -- proxy to client
  END :: BrokerMsg
  ENDS :: Int64 -> IdsHash -> BrokerMsg
  DELD :: BrokerMsg
@@ -760,16 +771,16 @@ newtype EncFwdResponse = EncFwdResponse ByteString
  deriving (Eq, Show)

 data FwdResponse = FwdResponse
-  { fwdCorrId :: CorrId,
+  { fwdCorrId :: C.CorrCbNonce,
    fwdResponse :: EncResponse
  }

 instance Encoding FwdResponse where
-  smpEncode FwdResponse {fwdCorrId = CorrId corrId, fwdResponse = EncResponse t} =
-    smpEncode (corrId, Tail t)
+  smpEncode FwdResponse {fwdCorrId, fwdResponse = EncResponse t} =
+    smpEncode (fwdCorrId, Tail t)
  smpP = do
-    (corrId, Tail t) <- smpP
-    pure FwdResponse {fwdCorrId = CorrId corrId, fwdResponse = EncResponse t}
+    (fwdCorrId, Tail t) <- smpP
+    pure FwdResponse {fwdCorrId, fwdResponse = EncResponse t}

 newtype EncResponse = EncResponse ByteString
  deriving (Eq, Show)
@@ -792,7 +803,7 @@ toMsgInfo = \case
  Message {msgId, msgTs} -> msgInfo msgId msgTs MTMessage
  MessageQuota {msgId, msgTs} -> msgInfo msgId msgTs MTQuota
  where
-    msgInfo msgId msgTs msgType = MsgInfo {msgId = decodeLatin1 $ B64.encode msgId, msgTs = systemToUTCTime msgTs, msgType}
+    msgInfo msgId msgTs msgType = MsgInfo {msgId = decodeLatin1 $ B64.encode $ unMsgId msgId, msgTs = systemToUTCTime msgTs, msgType}

 messageId :: Message -> MsgId
 messageId = \case
@@ -1324,7 +1335,10 @@ instance ProtocolTypeI p => FromJSON (ProtocolServer p) where
  parseJSON = strParseJSON "ProtocolServer"

 newtype BasicAuth = BasicAuth {unBasicAuth :: ByteString}
-  deriving (Eq, Ord, Show)
+  deriving (Ord, Show)
+
+instance Eq BasicAuth where
+  BasicAuth s == BasicAuth s' = BA.constEq s s'

 instance IsString BasicAuth where fromString = BasicAuth . B.pack

@@ -1490,7 +1504,34 @@ type RcvNtfPublicDhKey = C.PublicKeyX25519
 type RcvNtfDhSecret = C.DhSecretX25519

 -- | SMP message server ID.
-type MsgId = ByteString
+newtype MsgId = MsgId {unMsgId :: ByteString}
+  deriving (Eq, Show)
+
+instance C.CbNonceI MsgId where
+  unCbNonce (MsgId s) = B.take 24 s
+
+instance Encoding MsgId where
+  smpEncode (MsgId s) = smpEncode s
+  smpP = mkMsgId <$?> smpP
+
+instance StrEncoding MsgId where
+  strEncode (MsgId s) = strEncode s
+  strP = mkMsgId <$?> strP
+
+instance FromField MsgId where fromField = blobFieldDecoder mkMsgId
+
+instance ToField MsgId where toField (MsgId s) = toField $ Binary s
+
+mkMsgId :: ByteString -> Either String MsgId
+mkMsgId s
+  | B.length s >= 24 = Right $ MsgId s
+  | otherwise = Left "MsgId: invalid length"
+
+unsafeMsgId :: ByteString -> MsgId
+unsafeMsgId s = either error id $ mkMsgId s
+
+randomMsgId :: Int -> TVar ChaChaDRG -> STM MsgId
+randomMsgId n = fmap MsgId . C.randomBytes (max 24 n)

 -- | SMP message body.
 type MsgBody = ByteString
@@ -1778,7 +1819,7 @@ transmissionP THandleParams {sessionId, implySessId, serviceAuth} = do
 class (ProtocolTypeI (ProtoType msg), ProtocolEncoding v err msg, ProtocolEncoding v err (ProtoCommand msg), Show err, Show msg) => Protocol v err msg | msg -> v, msg -> err where
  type ProtoCommand msg = cmd | cmd -> msg
  type ProtoType msg = (sch :: ProtocolType) | sch -> msg
-  protocolClientHandshake :: Transport c => c 'TClient -> Maybe C.KeyPairX25519 -> C.KeyHash -> VersionRange v -> Bool -> Maybe (ServiceCredentials, C.KeyPairEd25519) -> (SessionId -> IO (Maybe EntitlementProof)) -> ExceptT TransportError IO (THandle v c 'TClient)
+  protocolClientHandshake :: Transport c => c 'TClient -> Maybe C.KeyPairX25519 -> C.KeyHash -> VersionRange v -> Bool -> Maybe (ServiceCredentials, C.KeyPairEd25519) -> ExceptT TransportError IO (THandle v c 'TClient)
  useServiceAuth :: ProtoCommand msg -> Bool
  protocolPing :: ProtoCommand msg
  protocolError :: msg -> Maybe err
@@ -1815,8 +1856,7 @@ instance PartyI p => ProtocolEncoding SMPVersion ErrorType (Command p) where
  encodeProtocol v = \case
    NEW NewQueueReq {rcvAuthKey = rKey, rcvDhKey = dhKey, auth_, subMode, queueReqData, ntfCreds}
      | v >= newNtfCredsSMPVersion -> new <> e (subMode, queueReqData, ntfCreds)
-      | v >= shortLinksSMPVersion -> new <> e (subMode, queueReqData)
-      | otherwise -> new <> e (subMode, senderCanSecure (queueReqMode <$> queueReqData))
+      | otherwise -> new <> e (subMode, queueReqData)
      where
        new = e (NEW_, ' ', rKey, dhKey, auth_)
    SUB -> e SUB_
@@ -1903,20 +1943,18 @@ instance ProtocolEncoding SMPVersion ErrorType Cmd where
    CT SCreator NEW_ -> Cmd SCreator <$> newCmd
      where
        newCmd
-          | v >= newNtfCredsSMPVersion = new smpP smpP
-          | v >= shortLinksSMPVersion = new smpP nothing
-          | otherwise = new (qReq <$> smpP) nothing
+          | v >= newNtfCredsSMPVersion = new smpP
+          | otherwise = new nothing
          where
            nothing = pure Nothing
-            new p2 p3 = NEW <$> do
+            new p3 = NEW <$> do
              rcvAuthKey <- _smpP
              rcvDhKey <- smpP
              auth_ <- smpP
              subMode <- smpP
-              queueReqData <- p2
+              queueReqData <- smpP
              ntfCreds <- p3
              pure NewQueueReq {rcvAuthKey, rcvDhKey, auth_, subMode, queueReqData, ntfCreds}
-            qReq sndSecure = Just $ if sndSecure then QRMessaging Nothing else QRContact Nothing
    CT SRecipient tag ->
      Cmd SRecipient <$> case tag of
        SUB_ -> pure SUB
@@ -1967,8 +2005,7 @@ instance ProtocolEncoding SMPVersion ErrorType BrokerMsg where
    IDS QIK {rcvId, sndId, rcvPublicDhKey = srvDh, queueMode, linkId, serviceId, serverNtfCreds}
      | v >= newNtfCredsSMPVersion -> ids <> e (queueMode, linkId, serviceId, serverNtfCreds)
      | v >= serviceCertsSMPVersion -> ids <> e (queueMode, linkId, serviceId)
-      | v >= shortLinksSMPVersion -> ids <> e (queueMode, linkId)
-      | otherwise -> ids <> e (senderCanSecure queueMode)
+      | otherwise -> ids <> e (queueMode, linkId)
      where
        ids = e (IDS_, ' ', rcvId, sndId, srvDh)
    LNK sId d -> e (LNK_, ' ', sId, d)
@@ -1982,8 +2019,8 @@ instance ProtocolEncoding SMPVersion ErrorType BrokerMsg where
    NID nId srvNtfDh -> e (NID_, ' ', nId, srvNtfDh)
    NMSG nmsgNonce encNMsgMeta -> e (NMSG_, ' ', nmsgNonce, encNMsgMeta)
    PKEY sid vr certKey -> e (PKEY_, ' ', sid, vr, certKey)
-    RRES (EncFwdResponse encBlock) -> e (RRES_, ' ', Tail encBlock)
-    PRES (EncResponse encBlock) -> e (PRES_, ' ', Tail encBlock)
+    RRES nonce_ (EncFwdResponse encBlock) -> fwdResp RRES_ nonce_ encBlock
+    PRES nonce_ (EncResponse encBlock) -> fwdResp PRES_ nonce_ encBlock
    END -> e END_
    ENDS n idsHash -> serviceResp ENDS_ n idsHash
    DELD -> e DELD_
@@ -2007,6 +2044,9 @@ instance ProtocolEncoding SMPVersion ErrorType BrokerMsg where
      serviceResp tag n idsHash
        | v >= rcvServiceSMPVersion = e (tag, ' ', n, idsHash)
        | otherwise = e (tag, ' ', n)
+      fwdResp tag nonce_ encBlock
+        | v >= fwdNoncesSMPVersion = e (tag, ' ', nonce_, Tail encBlock)
+        | otherwise = e (tag, ' ', Tail encBlock)

  protocolP v = \case
    MSG_ -> do
@@ -2016,19 +2056,17 @@ instance ProtocolEncoding SMPVersion ErrorType BrokerMsg where
        bodyP = EncRcvMsgBody . unTail <$> smpP
    ALLS_ -> pure ALLS
    IDS_
-      | v >= newNtfCredsSMPVersion -> ids smpP smpP smpP smpP
-      | v >= serviceCertsSMPVersion -> ids smpP smpP smpP nothing
-      | v >= shortLinksSMPVersion -> ids smpP smpP nothing nothing
-      | otherwise -> ids (qm <$> smpP) nothing nothing nothing
+      | v >= newNtfCredsSMPVersion -> ids smpP smpP
+      | v >= serviceCertsSMPVersion -> ids smpP nothing
+      | otherwise -> ids nothing nothing
      where
-        qm sndSecure = Just $ if sndSecure then QMMessaging else QMContact
        nothing = pure Nothing
-        ids p1 p2 p3 p4 = do
+        ids p3 p4 = do
          rcvId <- _smpP
          sndId <- smpP
          rcvPublicDhKey <- smpP
-          queueMode <- p1
-          linkId <- p2
+          queueMode <- smpP
+          linkId <- smpP
          serviceId <- p3
          serverNtfCreds <- p4
          pure $ IDS QIK {rcvId, sndId, rcvPublicDhKey, queueMode, linkId, serviceId, serverNtfCreds}
@@ -2038,8 +2076,8 @@ instance ProtocolEncoding SMPVersion ErrorType BrokerMsg where
    NID_ -> NID <$> _smpP <*> smpP
    NMSG_ -> NMSG <$> _smpP <*> smpP
    PKEY_ -> PKEY <$> _smpP <*> smpP <*> smpP
-    RRES_ -> RRES <$> (EncFwdResponse . unTail <$> _smpP)
-    PRES_ -> PRES <$> (EncResponse . unTail <$> _smpP)
+    RRES_ -> fwdRespP RRES EncFwdResponse
+    PRES_ -> fwdRespP PRES EncResponse
    END_ -> pure END
    ENDS_ -> serviceRespP ENDS
    DELD_ -> pure DELD
@@ -2056,6 +2094,9 @@ instance ProtocolEncoding SMPVersion ErrorType BrokerMsg where
      serviceRespP resp
        | v >= rcvServiceSMPVersion = resp <$> _smpP <*> smpP
        | otherwise = resp <$> _smpP <*> pure mempty
+      fwdRespP :: (Maybe C.CbNonce -> a -> BrokerMsg) -> (ByteString -> a) -> Parser BrokerMsg
+      fwdRespP resp enc = resp <$> (A.space *> nonceP) <*> (enc <$> A.takeByteString)
+      nonceP = if v >= fwdNoncesSMPVersion then smpP else pure Nothing

  fromProtocolError = \case
    PECmdSyntax -> CMD SYNTAX
@@ -2072,7 +2113,7 @@ instance ProtocolEncoding SMPVersion ErrorType BrokerMsg where
    -- PONG response must not have queue ID
    PONG -> noEntityMsg
    PKEY {} -> noEntityMsg
-    RRES _ -> noEntityMsg
+    RRES {} -> noEntityMsg
    ALLS -> noEntityMsg
    RNAME {} -> noEntityMsg
    -- other broker responses must have queue ID
@@ -2408,7 +2449,9 @@ tDecodeServer THandleParams {sessionId, thVersion = v, implySessId} = \case
          where
            cmdOrErr = parseProtocol @v @err @cmd v command >>= checkCredentials tAuth entityId
            t :: a -> (CorrId, EntityId, a)
-            t = (corrId,entityId,)
+            -- IDs are slices of the ~16 KB received block and are kept as subscription keys,
+            -- so without a copy one live key retains the whole block
+            t = (CorrId $ B.copy $ bs corrId,EntityId $ B.copy $ unEntityId entityId,)
        Left _ -> tError corrId PEBlock
    | otherwise -> tError corrId PESession
  Left _ -> tError "" PEBlock
@@ -98,13 +98,12 @@ import Network.Socket (ServiceName, Socket, socketToHandle)
 import qualified Network.TLS as TLS
 import Numeric.Natural (Natural)
 import Simplex.Messaging.Agent.Lock
-import Simplex.Messaging.Client (ProtocolClient (thParams), ProtocolClientError (..), SMPClient, SMPClientError, clientHandlers, forwardSMPTransmission, smpProxyError, temporaryClientError, transportHost')
+import Simplex.Messaging.Client (ProtocolClient (thParams), ProtocolClientError (..), SMPClient, SMPClientError, clientHandlers, forwardSMPTransmission, smpProxyError, temporaryClientError)
 import Simplex.Messaging.Client.Agent (OwnServer, SMPClientAgent (..), SMPClientAgentEvent (..), closeSMPClientAgent, getSMPServerClient'', isOwnServer, lookupSMPServerClient, getConnectedSMPServerClient)
 import qualified Simplex.Messaging.Crypto as C
 import Simplex.Messaging.Encoding
 import Simplex.Messaging.Encoding.String
 import Simplex.Messaging.Protocol
-import Simplex.Messaging.Server.AddressStats (AddrStats, ServerAddrStats (..), addAddrCounter, addressStatsThread, incAddrCounter, printTopAddresses, withAddrStats)
 import Simplex.Messaging.Server.Control
 import Simplex.Messaging.Server.Env.STM as Env
 import Simplex.Messaging.Server.Expiration
@@ -125,7 +124,6 @@ import Simplex.Messaging.TMap (TMap)
 import qualified Simplex.Messaging.TMap as TM
 import Simplex.Messaging.Transport
 import Simplex.Messaging.Transport.Buffer (trimCR)
-import Simplex.Messaging.Transport.Client (TransportHost (..))
 import Simplex.Messaging.Transport.Server
 import Simplex.Messaging.Util
 import Simplex.Messaging.Version
@@ -201,7 +199,6 @@ smpServer started cfg@ServerConfig {transports, transportConfig = tCfg, startOpt
            <> expireMessagesThread_ cfg
            <> serverStatsThread_ cfg
            <> prometheusMetricsThread_ cfg
-            <> addressStatsThread_ cfg
            <> controlPortThread_ cfg
    )
    `finally` stopServer s
@@ -219,12 +216,11 @@ smpServer started cfg@ServerConfig {transports, transportConfig = tCfg, startOpt
          runTransportServerState_ ss started tcpPort defaultSupportedParamsHTTPS combinedCreds tCfg $ \s (sniUsed, h) ->
            case cast h of
              Just (TLS {tlsContext} :: TLS 'TServer) | sniUsed -> labelMyThread "https client" >> attachHTTP s tlsContext
-              _ -> runClient srvCert srvSignKey t s h `runReaderT` env
+              _ -> runClient srvCert srvSignKey t h `runReaderT` env
          where
            combinedCreds = TLSServerCredential {credential = smpCreds, sniCredential = Just httpCreds}
        _ ->
-          runTransportServerState_ ss started tcpPort defaultSupportedParams TLSServerCredential {credential = smpCreds, sniCredential = Nothing} tCfg $ \s (_, h) ->
-            runClient srvCert srvSignKey t s h `runReaderT` env
+          runTransportServerState ss started tcpPort defaultSupportedParams smpCreds tCfg $ \h -> runClient srvCert srvSignKey t h `runReaderT` env

    sigIntHandlerThread :: M s ()
    sigIntHandlerThread = do
@@ -519,10 +515,6 @@ smpServer started cfg@ServerConfig {transports, transportConfig = tCfg, startOpt
      [logServerStats logStatsStartTime interval serverStatsLogFile]
    serverStatsThread_ _ = []

-    addressStatsThread_ :: ServerConfig s -> [M s ()]
-    addressStatsThread_ ServerConfig {addressStats = Just statsCfg} = [asks addrStats >>= mapM_ (liftIO . addressStatsThread statsCfg)]
-    addressStatsThread_ _ = []
-
    logServerStats :: Int64 -> Int64 -> FilePath -> M s ()
    logServerStats startAt logInterval statsFilePath = do
      labelMyThread "logServerStats"
@@ -707,7 +699,7 @@ smpServer started cfg@ServerConfig {transports, transportConfig = tCfg, startOpt
      pure ServerMetrics {statsData = d, activeQueueCounts = ps, activeNtfCounts = psNtf, entityCounts, rtsOptions}

    getRealTimeMetrics :: Env s -> IO RealTimeMetrics
-    getRealTimeMetrics Env {sockets, msgStore_ = ms, server = srv@Server {subscribers, ntfSubscribers}, addrStats} = do
+    getRealTimeMetrics Env {sockets, msgStore_ = ms, server = srv@Server {subscribers, ntfSubscribers}} = do
      socketStats <- mapM (traverse getSocketStats) =<< readTVarIO sockets
 #if MIN_VERSION_base(4,18,0)
      threadsCount <- length <$> listThreads
@@ -719,8 +711,7 @@ smpServer started cfg@ServerConfig {transports, transportConfig = tCfg, startOpt
      smpSubs <- getSubscribersMetrics subscribers
      ntfSubs <- getSubscribersMetrics ntfSubscribers
      loadedCounts <- loadedQueueCounts $ fromMsgStore ms
-      addressHistograms <- mapM (readIORef . addrHistograms) addrStats
-      pure RealTimeMetrics {socketStats, threadsCount, clientsCount, deliveredSubs, deliveredTimes, smpSubs, ntfSubs, loadedCounts, addressHistograms}
+      pure RealTimeMetrics {socketStats, threadsCount, clientsCount, deliveredSubs, deliveredTimes, smpSubs, ntfSubs, loadedCounts}
      where
        getSubscribersMetrics ServerSubscribers {queueSubscribers, serviceSubscribers, totalServiceSubs, subClients} = do
          subsCount <- M.size <$> getSubscribedClients queueSubscribers
@@ -741,21 +732,19 @@ smpServer started cfg@ServerConfig {transports, transportConfig = tCfg, startOpt
                Nothing -> acc
                Just (_, ts) -> (cnt + 1, updateTimeBuckets ts ts' times)

-    runClient :: Transport c => X.CertificateChain -> C.APrivateSignKey -> TProxy c 'TServer -> Socket -> c 'TServer -> M s ()
-    runClient srvCert srvSignKey tp sock h = do
-      stats_ <- asks addrStats
-      withAddrStats (addrStatsMap <$> stats_) sock $ \addrStats_ -> do
-        ms <- asks msgStore
-        g <- asks random
-        idSize <- asks $ queueIdBytes . config
-        kh <- asks serverIdentity
-        ks <- atomically . C.generateKeyPair =<< asks random
-        ServerConfig {smpServerVRange, smpHandshakeTimeout, information} <- asks config
-        let serverInfo = LB.toStrict . J.encode <$> information
-        labelMyThread $ "smp handshake for " <> transportName tp
-        liftIO (timeout smpHandshakeTimeout . runExceptT $ smpServerHandshake srvCert srvSignKey h ks kh smpServerVRange serverInfo $ getClientService ms g idSize) >>= \case
-          Just (Right th) -> runClientTransport addrStats_ th
-          _ -> pure ()
+    runClient :: Transport c => X.CertificateChain -> C.APrivateSignKey -> TProxy c 'TServer -> c 'TServer -> M s ()
+    runClient srvCert srvSignKey tp h = do
+      ms <- asks msgStore
+      g <- asks random
+      idSize <- asks $ queueIdBytes . config
+      kh <- asks serverIdentity
+      ks <- atomically . C.generateKeyPair =<< asks random
+      ServerConfig {smpServerVRange, smpHandshakeTimeout, information} <- asks config
+      let serverInfo = LB.toStrict . J.encode <$> information
+      labelMyThread $ "smp handshake for " <> transportName tp
+      liftIO (timeout smpHandshakeTimeout . runExceptT $ smpServerHandshake srvCert srvSignKey h ks kh smpServerVRange serverInfo $ getClientService ms g idSize) >>= \case
+        Just (Right th) -> runClientTransport th
+        _ -> pure ()

    getClientService :: s -> TVar ChaChaDRG -> Int -> SMPServiceRole -> X.CertificateChain -> XV.Fingerprint -> ExceptT TransportError IO ServiceId
    getClientService ms g idSize role cert fp = do
@@ -1051,10 +1040,7 @@ smpServer started cfg@ServerConfig {transports, transportConfig = tCfg, startOpt
                hPutStrLn h "saving server state..."
                unliftIO u $ saveServer False
                hPutStrLn h "server state saved!"
-              CPAddresses name n_ -> withUserRole $ do
-                stats_ <- unliftIO u $ asks addrStats
-                printTopAddresses h (addrStatsMap <$> stats_) name n_
-              CPHelp -> hPutStrLn h "commands: stats, stats-rts, clients, sockets, socket-threads, threads, server-info, delete, addresses, save, help, quit"
+              CPHelp -> hPutStrLn h "commands: stats, stats-rts, clients, sockets, socket-threads, threads, server-info, delete, save, help, quit"
              CPQuit -> pure ()
              CPSkip -> pure ()
              where
@@ -1075,13 +1061,13 @@ smpServer started cfg@ServerConfig {transports, transportConfig = tCfg, startOpt
                    logError "Unauthorized control port command"
                    hPutStrLn h "AUTH"

-runClientTransport :: forall c s. (Transport c, MsgStoreClass s) => Maybe (AddrStats SMPAddrCounter) -> THandleSMP c 'TServer -> M s ()
-runClientTransport addrStats_ h@THandle {params = thParams@THandleParams {sessionId}} = do
+runClientTransport :: forall c s. (Transport c, MsgStoreClass s) => THandleSMP c 'TServer -> M s ()
+runClientTransport h@THandle {params = thParams@THandleParams {sessionId}} = do
  q <- asks $ tbqSize . config
  ts <- liftIO getSystemTime
  nextClientId <- asks clientSeq
  clientId <- atomically $ stateTVar nextClientId $ \next -> (next, next + 1)
-  c <- liftIO $ newClient clientId q thParams ts addrStats_
+  c <- liftIO $ newClient clientId q thParams ts
  runClientThreads c `finally` clientDisconnected c
  where
    runClientThreads :: Client s -> M s ()
@@ -1106,6 +1092,7 @@ controlPortAuth h user admin role auth = do
  readTVarIO role >>= \case
    CPRNone -> do
      atomically $ writeTVar role $! newRole
+      when (newRole == CPRNone) $ logWarn "ControlPort: failed auth"
      hPutStrLn h $ currentRole newRole
    r -> hPutStrLn h $ currentRole r <> if r == newRole then "" else ", start new session to change."
  where
@@ -1158,19 +1145,18 @@ cancelSub s = case subThread s of
 type VerifiedTransmissionOrError s = Either (Transmission BrokerMsg) (VerifiedTransmission s)

 receive :: forall c s. (Transport c, MsgStoreClass s) => THandleSMP c 'TServer -> s -> Client s -> M s ()
-receive h@THandle {params = THandleParams {thAuth, sessionId}} ms Client {rcvQ, sndQ, rcvActiveAt, clientAddrStats} = do
+receive h@THandle {params = THandleParams {thAuth, sessionId}} ms c@Client {rcvQ, rcvActiveAt} = do
  labelMyThread . B.unpack $ "client $" <> encode sessionId <> " receive"
  sa <- asks serverActive
  stats <- asks serverStats
+  authDelay <- asks $ authErrorDelay . config
  liftIO $ forever $ do
    ts <- tGetServer h
    unlessM (readTVarIO sa) $ throwIO $ userError "server stopped"
-    atomically . (writeTVar rcvActiveAt $!) =<< getSystemTime
+    receivedAt <- getSystemTime
+    atomically $ writeTVar rcvActiveAt $! receivedAt
    let (es, ts') = partitionEithers $ L.toList ts
        errs = map (second ERR) es
-    forM_ clientAddrStats $ \s -> do
-      unless (null es) $ addAddrCounter s SACErrors $ length es
-      forM_ ts' $ \(_, _, (_, _, cmd)) -> incAddrCounter s $ smpCmdCounter cmd
    errs' <- case ts' of
      (_, _, (_, _, Cmd p cmd)) : rest -> do
        let service = peerClientService =<< thAuth
@@ -1184,7 +1170,7 @@ receive h@THandle {params = THandleParams {thAuth, sessionId}} ms Client {rcvQ,
        mapM_ (atomically . writeTBQueue rcvQ) $ L.nonEmpty cmds
        pure $ errs ++ errs'
      [] -> pure errs
-    mapM_ (atomically . writeTBQueue sndQ . (,[])) $ L.nonEmpty errs'
+    mapM_ (sendResponses c stats authDelay receivedAt . (,[])) $ L.nonEmpty errs'
  where
    sameParty :: SParty p -> SignedTransmission Cmd -> Bool
    sameParty p (_, _, (_, _, Cmd p' _)) = isJust $ testEquality p p'
@@ -1198,9 +1184,7 @@ receive h@THandle {params = THandleParams {thAuth, sessionId}} ms Client {rcvQ,
    verified :: ServerStats -> SignedTransmission Cmd -> VerificationResult s -> IO (VerifiedTransmissionOrError s)
    verified stats (_, _, t@(corrId, entId, Cmd _ command)) = \case
      VRVerified q -> pure $ Right (q, t)
-      VRFailed e -> do
-        forM_ clientAddrStats (`incAddrCounter` SACErrors)
-        Left (corrId, entId, ERR e) <$ when (e == AUTH) incAuthStat
+      VRFailed e -> Left (corrId, entId, ERR e) <$ when (e == AUTH) incAuthStat
        where
          incAuthStat = case command of
            SEND {} -> incStat $ msgSentAuth stats
@@ -1209,6 +1193,27 @@ receive h@THandle {params = THandleParams {thAuth, sessionId}} ms Client {rcvQ,
            GET -> incStat $ msgGetAuth stats
            _ -> pure ()

+isAuthError :: Transmission BrokerMsg -> Bool
+isAuthError (_, _, r) = case r of
+  ERR AUTH -> True
+  _ -> False
+
+sendResponses :: Client s -> ServerStats -> Int64 -> SystemTime -> (NonEmpty (Transmission BrokerMsg), [Transmission BrokerMsg]) -> IO ()
+sendResponses c@Client {sndQ} stats authDelay since rs@(ts, _)
+  | any isAuthError ts = sendAfterDelay c stats authDelay since rs
+  | otherwise = atomically $ writeTBQueue sndQ rs
+
+sendAfterDelay :: Client s -> ServerStats -> Int64 -> SystemTime -> (NonEmpty (Transmission BrokerMsg), [Transmission BrokerMsg]) -> IO ()
+sendAfterDelay c@Client {sndQ, clientTHParams = THandleParams {sessionId}} stats delay since rs
+  | delay > 0 = do
+      elapsed <- subtract (microseconds since) . microseconds <$> getSystemTime
+      when (elapsed >= delay) $ incStat $ authDelayExceeded stats
+      forkClient c (B.unpack $ "client $" <> encode sessionId <> " auth") $ threadDelay' (delay - elapsed `mod` delay) >> write
+  | otherwise = write
+  where
+    write = atomically $ writeTBQueue sndQ rs
+    microseconds (MkSystemTime s ns) = s * 1000000 + fromIntegral (ns `div` 1000)
+
 send :: Transport c => MVar (THandleSMP c 'TServer) -> Client s -> IO ()
 send th c@Client {sndQ, msgQ, clientTHParams = THandleParams {sessionId}} = do
  labelMyThread . B.unpack $ "client $" <> encode sessionId <> " send"
@@ -1337,11 +1342,6 @@ isContactQueue QueueRec {queueMode, senderKey} = case queueMode of
  Just QMContact -> True
  Nothing -> isNothing senderKey -- for backward compatibility with pre-SKEY contact addresses

-isSecuredMsgQueue :: QueueRec -> Bool
-isSecuredMsgQueue QueueRec {queueMode, senderKey} = case queueMode of
-  Just QMContact -> False
-  _ -> isJust senderKey
-
 -- Random correlation ID is used as a nonce in case crypto_box authenticator is used to authorize transmission
 verifyCmdAuthorization :: Maybe (THandleAuth 'TServer) -> Maybe TAuthorizations -> ByteString -> CorrId -> C.APublicAuthKey -> Bool
 verifyCmdAuthorization thAuth tAuth authorized corrId key = maybe False (verify key) tAuth
@@ -1357,7 +1357,7 @@ verifyCmdAuthorization thAuth tAuth authorized corrId key = maybe False (verify

 verifyCmdAuth :: Maybe (THandleAuth 'TServer) -> C.PublicKeyX25519 -> C.CbAuthenticator -> ByteString -> CorrId -> Bool
 verifyCmdAuth thAuth k authenticator authorized (CorrId corrId) = case thAuth of
-  Just THAuthServer {serverPrivKey = pk} -> C.cbVerify k pk (C.cbNonce corrId) authenticator authorized
+  Just THAuthServer {serverPrivKey = pk} -> either (const False) (\nonce -> C.cbVerify k pk nonce authenticator authorized) $ C.cbNonce corrId
  Nothing -> False

 dummyVerifyCmd :: Maybe (THandleAuth 'TServer) -> Maybe TAuthorizations -> ByteString -> CorrId -> Bool
@@ -1395,17 +1395,20 @@ client :: forall s. MsgStoreClass s => Server s -> s -> Client s -> M s ()
 client
  Server {subscribers, ntfSubscribers}
  ms
-  clnt@Client {clientId, rcvQ, sndQ, msgQ, clientTHParams = thParams'@THandleParams {sessionId}, procThreads, clientAddrStats} = do
+  clnt@Client {clientId, rcvQ, sndQ, msgQ, clientTHParams = thParams'@THandleParams {sessionId}, procThreads} = do
    labelMyThread . B.unpack $ "client $" <> encode sessionId <> " commands"
+    stats <- asks serverStats
+    authDelay <- asks $ authErrorDelay . config
    let clntServiceId = (\THClientService {serviceId} -> serviceId) <$> (peerClientService =<< thAuth thParams')
        process batchSubs t acc@(rs, msgs) =
          (maybe acc (\(!r, !msg_) -> (r : rs, maybe msgs (: msgs) msg_)))
            <$> processCommand clntServiceId batchSubs t
    forever $ do
      batch <- atomically (readTBQueue rcvQ)
+      processedAt <- liftIO getSystemTime
      batchSubs <- prepareBatchSubs clntServiceId batch
      foldrM (process batchSubs) ([], []) batch
-        >>= \(rs_, msgs) -> mapM_ (atomically . writeTBQueue sndQ . (,msgs)) (L.nonEmpty rs_)
+        >>= \(rs_, msgs) -> mapM_ (liftIO . sendResponses clnt stats authDelay processedAt . (,msgs)) (L.nonEmpty rs_)
  where
    prepareBatchSubs ::
      Maybe ServiceId ->
@@ -1440,30 +1443,25 @@ client
          getRelay = do
            ProxyAgent {smpAgent = a} <- asks proxyAgent
            liftIO (getConnectedSMPServerClient a srv) >>= \case
-              Just r -> Just <$> proxyServerResponse a SACPrxyConnected r
+              Just r -> Just <$> proxyServerResponse a r
              Nothing ->
                forkProxiedCmd $
                  liftIO (runExceptT (getSMPServerClient'' a srv) `E.catches` clientHandlers)
-                    >>= proxyServerResponse a SACPrxyNew
-          proxyServerResponse :: SMPClientAgent 'Sender -> SMPAddrCounter -> Either SMPClientError (OwnServer, SMPClient) -> M s BrokerMsg
-          proxyServerResponse a otherCounter smp_ = do
+                    >>= proxyServerResponse a
+          proxyServerResponse :: SMPClientAgent 'Sender -> Either SMPClientError (OwnServer, SMPClient) -> M s BrokerMsg
+          proxyServerResponse a smp_ = do
            ServerStats {pRelays, pRelaysOwn} <- asks serverStats
            let inc = mkIncProxyStats pRelays pRelaysOwn
            case smp_ of
              Right (own, smp) -> do
                inc own pRequests
                case proxyResp smp of
-                  r@PKEY {} -> do
-                    incAddrStats $ proxyDestCounter own smp SACPrxyOwn SACPrxyOnion otherCounter
-                    r <$ inc own pSuccesses
-                  r -> do
-                    incAddrStats SACPrxyFailed
-                    r <$ inc own pErrorsCompat
+                  r@PKEY {} -> r <$ inc own pSuccesses
+                  r -> r <$ inc own pErrorsCompat
              Left e -> do
                let own = isOwnServer a srv
                inc own pRequests
                inc own $ if temporaryClientError e then pErrorsConnect else pErrorsOther
-                incAddrStats SACPrxyFailed
                logWarn $ "Error connecting: " <> decodeLatin1 (strEncode $ host srv) <> " " <> tshow e
                pure . ERR $ smpProxyError e
            where
@@ -1481,26 +1479,19 @@ client
        ServerStats {pMsgFwds, pMsgFwdsOwn} <- asks serverStats
        let inc = mkIncProxyStats pMsgFwds pMsgFwdsOwn
        liftIO (lookupSMPServerClient a sessId) >>= \case
-          Just (own, smp) -> do
+          Just (own, smp) | Right fwdCorrId <- C.corrCbNonce (bs corrId) -> do
            inc own pRequests
-            let delivered = incAddrStats (proxyDestCounter own smp SACPfwdOwn SACPfwdOnion SACPfwdOther) >> inc own pSuccesses
            forkProxiedCmd $ do
-              liftIO (runExceptT (forwardSMPTransmission smp corrId fwdV pubKey encBlock) `E.catches` clientHandlers)  >>= \case
-                Right r -> PRES r <$ delivered
+              liftIO (runExceptT (forwardSMPTransmission smp fwdCorrId fwdV pubKey encBlock) `E.catches` clientHandlers)  >>= \case
+                Right (nonce_, r) -> PRES nonce_ r <$ inc own pSuccesses
                Left e -> ERR (smpProxyError e) <$ case e of
-                  PCEProtocolError {} -> delivered
-                  _ -> incAddrStats SACPfwdFailed >> inc own pErrorsOther
-          Nothing -> incAddrStats SACPfwdFailed >> inc False pRequests >> inc False pErrorsConnect $> Just (ERR $ PROXY NO_SESSION)
+                  PCEProtocolError {} -> inc own pSuccesses
+                  _ -> inc own pErrorsOther
+          Just _ -> pure $ Just $ ERR $ CMD SYNTAX
+          Nothing -> inc False pRequests >> inc False pErrorsConnect $> Just (ERR $ PROXY NO_SESSION)
      where
        forkProxiedCmd :: M s BrokerMsg -> M s (Maybe BrokerMsg)
        forkProxiedCmd = forkCmd serverClientConcurrency corrId (EntityId sessId)
-        proxyDestCounter :: OwnServer -> SMPClient -> SMPAddrCounter -> SMPAddrCounter -> SMPAddrCounter -> SMPAddrCounter
-        proxyDestCounter own smp ownCounter onionCounter otherCounter
-          | own = ownCounter
-          | THOnionHost _ <- transportHost' smp = onionCounter
-          | otherwise = otherCounter
-    incAddrStats :: SMPAddrCounter -> M s ()
-    incAddrStats c = liftIO $ forM_ clientAddrStats (`incAddrCounter` c)
    -- Run a slow command on a thread
    forkCmd :: (ServerConfig s -> Int) -> CorrId -> EntityId -> M s BrokerMsg -> M s (Maybe a)
    forkCmd concurrency corrId entId cmdAction = do
@@ -1986,7 +1977,7 @@ client
            getDelivered :: Sub -> STM (Maybe (ServerSub, SystemSeconds))
            getDelivered Sub {delivered, subThread} = do
              readTVar delivered $>>= \(msgId', ts) ->
-                if msgId == msgId' || B.null msgId
+                if msgId == msgId'
                  then writeTVar delivered Nothing $> Just (subThread, ts)
                  else pure Nothing
            updateStats :: ServerStats -> Bool -> SystemSeconds -> Message -> IO ()
@@ -2032,7 +2023,7 @@ client
                      when (isJust (queueData qr) && isSecuredMsgQueue qr) $ void $ liftIO $
                        deleteQueueLinkData (queueStore ms) q
                      ServerConfig {messageExpiration, expireMessagesOnSend, msgIdBytes} <- asks config
-                      msgId <- randomId' msgIdBytes
+                      msgId <- atomically . randomMsgId msgIdBytes =<< asks random
                      msg_ <- liftIO $ runExceptT $ do
                        when expireMessagesOnSend $ mapM_ (expireMessages stats) messageExpiration
                        msg <- liftIO $ mkMessage msgId body
@@ -2145,7 +2136,7 @@ client
              liftIO $ storeNtf ns nId ntf
              incStat . ntfCount =<< asks serverStats

-            mkMessageNotification :: ByteString -> SystemTime -> RcvNtfDhSecret -> M s MsgNtf
+            mkMessageNotification :: MsgId -> SystemTime -> RcvNtfDhSecret -> M s MsgNtf
            mkMessageNotification msgId msgTs rcvNtfDhSecret = do
              ntfNonce <- atomically . C.randomCbNonce =<< asks random
              let msgMeta = NMsgMeta {msgId, msgTs}
@@ -2154,14 +2145,16 @@ client

        processForwardedCommand :: EncFwdTransmission -> M s (Maybe BrokerMsg)
        processForwardedCommand (EncFwdTransmission s) = fmap (either (Just . ERR) id) . runExceptT $ do
+          startedAt <- liftIO getSystemTime
          THAuthServer {serverPrivKey, sessSecret'} <- maybe (throwE $ transportErr TENoServerAuth) pure (thAuth thParams')
          sessSecret <- maybe (throwE $ transportErr TENoServerAuth) pure sessSecret'
-          let proxyNonce = C.cbNonce $ bs corrId
+          proxyNonce <- liftEitherWith (const CRYPTO) $ C.cbNonce $ bs corrId
          s' <- liftEitherWith (const CRYPTO) $ C.cbDecryptNoPad sessSecret proxyNonce s
          FwdTransmission {fwdCorrId, fwdVersion, fwdKey, fwdTransmission = EncTransmission et} <- liftEitherWith (const $ CMD SYNTAX) $ smpDecode s'
+          unless (fwdVersion `isCompatible` thServerVRange thParams') $ throwE $ transportErr TEVersion
          let clientSecret = C.dh' fwdKey serverPrivKey
-              clientNonce = C.cbNonce $ bs fwdCorrId
-          b <- liftEitherWith (const CRYPTO) $ C.cbDecrypt clientSecret clientNonce et
+              clientNonce = fwdCorrId
+          b <- liftEitherWith (const CRYPTO) $ C.cbDecrypt clientSecret (encTransmissionNonce fwdVersion clientNonce) et
          let clntTHParams = smpTHParamsSetVersion fwdVersion thParams'
          -- only allowing single forwarded transactions
          t' <- case tParse clntTHParams b of
@@ -2174,9 +2167,13 @@ client
                  TBError _ _ : _ -> throwE BLOCK
                  TBTransmission b' _ : _ -> pure b'
                  TBTransmissions b' _ _ : _ -> pure b'
-                r2 <- liftEitherWith (const BLOCK) $ EncResponse <$> C.cbEncrypt clientSecret (C.reverseNonce clientNonce) r' paddedProxiedTLength
+                nonce_ <-
+                  if fwdVersion >= fwdNoncesSMPVersion
+                    then Just <$> (atomically . C.randomCbNonce =<< asks random)
+                    else pure Nothing
+                r2 <- liftEitherWith (const BLOCK) $ EncResponse <$> C.cbEncrypt clientSecret (fromMaybe (C.reverseNonce clientNonce) nonce_) r' paddedProxiedTLength
                let fr = FwdResponse {fwdCorrId, fwdResponse = r2}
-                pure $ RRES $ EncFwdResponse $ C.cbEncryptNoPad sessSecret (C.reverseNonce proxyNonce) (smpEncode fr)
+                pure $ RRES nonce_ $ EncFwdResponse $ C.cbEncryptNoPad sessSecret (C.reverseNonce proxyNonce) (smpEncode fr)
          -- the inner response, or Nothing if forked (RSLV).
          r_ <- lift (rejectOrVerify clntThAuth t') >>= \case
            -- rejectOrVerify filters allowed commands, no need to repeat it here.
@@ -2192,7 +2189,11 @@ client
              _ -> Just . maybe (corrId', entId', ERR INTERNAL) fst <$> lift (processCommand Nothing (Right (M.empty, M.empty, M.empty)) t'')
          stats <- asks serverStats
          incStat $ pMsgFwdsRecv stats
-          traverse encodeResp r_
+          traverse encodeResp r_ >>= \case
+            Just rres | any isAuthError r_ -> do
+              authDelay <- asks $ authErrorDelay . config
+              Nothing <$ liftIO (sendAfterDelay clnt stats authDelay startedAt ([(corrId, NoEntity, rres)], []))
+            rres_ -> pure rres_
          where
            rejectOrVerify :: Maybe (THandleAuth 'TServer) -> SignedTransmissionOrError ErrorType Cmd -> M s (VerifiedTransmissionOrError s)
            rejectOrVerify clntThAuth = \case
@@ -2218,7 +2219,7 @@ client
          MessageQuota {} -> RcvMsgQuota msgTs'
          where
            encrypt :: KnownNat i => C.MaxLenBS i -> RcvMessage
-            encrypt body = RcvMessage msgId' . EncRcvMsgBody $ C.cbEncryptMaxLenBS (rcvDhSecret qr) (C.cbNonce msgId') body
+            encrypt body = RcvMessage msgId' . EncRcvMsgBody $ C.cbEncryptMaxLenBS (rcvDhSecret qr) msgId' body
            msgId' = messageId msg
            msgTs' = messageTs msg

@@ -2267,7 +2268,7 @@ client
                    SubPending -> QSubPending
                    SubThread _ -> QSubThread
                ProhibitSub -> pure QProhibitSub
-              qDelivered <- decodeLatin1 . encode . fst <$$> readTVarIO delivered
+              qDelivered <- decodeLatin1 . encode . unMsgId . fst <$$> readTVarIO delivered
              pure QSub {qSubThread, qDelivered}

        ok :: Transmission BrokerMsg
@@ -1,250 +0,0 @@
-{-# LANGUAGE LambdaCase #-}
-{-# LANGUAGE NamedFieldPuns #-}
-{-# LANGUAGE OverloadedStrings #-}
-{-# LANGUAGE TupleSections #-}
-
-module Simplex.Messaging.Server.AddressStats
-  ( AddrKey (..),
-    AddrCounter (..),
-    AddrStats (..),
-    AddrStatsMap,
-    AddrHistogram (..),
-    ServerAddrStats (..),
-    AddressStatsConfig (..),
-    defaultAddressStatsPeriod,
-    countBounds,
-    kilobyteBounds,
-    addrKey,
-    addrKeyText,
-    counterByName,
-    newServerAddrStats,
-    withAddrStats,
-    openAddrStats,
-    closeAddrStats,
-    incAddrCounter,
-    addAddrCounter,
-    rolloverAddrStats,
-    addressStatsThread,
-    topAddresses,
-    printTopAddresses,
-    addressesArgsP,
-    addressesArgs,
-    addrHistogramMetrics,
-  )
-where
-
-import Control.Applicative (optional)
-import Control.Monad
-import Control.Monad.IO.Unlift
-import qualified Data.Attoparsec.ByteString.Char8 as A
-import Data.Bits (shiftL, shiftR, (.&.), (.|.))
-import Data.ByteString.Char8 (ByteString)
-import Data.IORef
-import Data.Int (Int64)
-import qualified Data.IntMap.Strict as IM
-import Data.List (find, foldl', sortOn)
-import Data.Map.Strict (Map)
-import qualified Data.Map.Strict as M
-import Data.Maybe (fromMaybe)
-import Data.Ord (Down (..))
-import Data.Text (Text)
-import qualified Data.Text as T
-import Data.Text.Encoding (encodeUtf8)
-import qualified Data.Text.IO as T
-import Data.Word (Word32, Word64)
-import Network.Socket (SockAddr (..), Socket, getPeerName, hostAddress6ToTuple, hostAddressToTuple)
-import Numeric (showHex)
-import Simplex.Messaging.TMap (TMap)
-import qualified Simplex.Messaging.TMap as TM
-import Simplex.Messaging.Util (atomicModifyIORef'_, bshow, labelMyThread, safeDecodeUtf8, threadDelay', tshow, whenM, (<$$>))
-import System.IO (Handle, hPutStrLn)
-import UnliftIO.Exception (finally, tryAny)
-import UnliftIO.STM
-
-data AddrKey
-  = AKIPv4 Word32
-  | AKIPv6 Word64
-  deriving (Eq, Ord, Show)
-
-class (Ord c, Enum c, Bounded c) => AddrCounter c where
-  counterName :: c -> Text
-  counterBounds :: c -> [Int]
-  counterBounds _ = countBounds
-  connectionsCounter :: c
-
-data AddrStats c = AddrStats
-  { connectionsCount :: TVar Int,
-    current :: Map c (IORef Int),
-    previous :: Map c (IORef Int)
-  }
-
-type AddrStatsMap c = TMap AddrKey (AddrStats c)
-
-data AddrHistogram = AddrHistogram
-  { bucketCounts :: [Int],
-    countSum :: Int,
-    addressCount :: Int,
-    periodMax :: Int
-  }
-  deriving (Eq, Show)
-
-data ServerAddrStats c = ServerAddrStats
-  { addrStatsMap :: AddrStatsMap c,
-    addrHistograms :: IORef (Map c AddrHistogram)
-  }
-
-newtype AddressStatsConfig = AddressStatsConfig
-  { period :: Int64
-  }
-  deriving (Show)
-
-defaultAddressStatsPeriod :: Int64
-defaultAddressStatsPeriod = 300
-
-countBounds :: [Int]
-countBounds = r10Bounds 5
-
-kilobyteBounds :: [Int]
-kilobyteBounds = r10Bounds 7
-
-r10Bounds :: Int -> [Int]
-r10Bounds decades =
-  [1 .. 9]
-    <> [(r * 10 ^ d + 50) `div` 100 | d <- [1 .. decades], r <- [100, 125, 160, 200, 250, 315, 400, 500, 630, 800]]
-    <> [10 ^ (decades + 1)]
-
-addrKey :: SockAddr -> Maybe AddrKey
-addrKey = \case
-  SockAddrInet _ a ->
-    let (b1, b2, b3, b4) = hostAddressToTuple a
-     in Just $ AKIPv4 $ foldl' (\acc b -> acc `shiftL` 8 .|. fromIntegral b) 0 [b1, b2, b3, b4]
-  SockAddrInet6 _ _ a _ -> Just $ case hostAddress6ToTuple a of
-    (0, 0, 0, 0, 0, 0xffff, w1, w2) -> AKIPv4 $ fromIntegral w1 `shiftL` 16 .|. fromIntegral w2
-    (w1, w2, w3, w4, _, _, _, _) -> AKIPv6 $ foldl' (\acc w -> acc `shiftL` 16 .|. fromIntegral w) 0 [w1, w2, w3, w4]
-  _ -> Nothing
-
-addrKeyText :: AddrKey -> Text
-addrKeyText = \case
-  AKIPv4 a -> T.intercalate "." $ map (\s -> tshow $ (a `shiftR` s) .&. 0xff) [24, 16, 8, 0]
-  AKIPv6 p -> T.intercalate ":" (map (\s -> T.pack $ showHex ((p `shiftR` s) .&. 0xffff) "") [48, 32, 16, 0]) <> "::/64"
-
-counterByName :: AddrCounter c => Text -> Maybe c
-counterByName name = find ((name ==) . counterName) [minBound .. maxBound]
-
-newServerAddrStats :: AddrCounter c => IO (ServerAddrStats c)
-newServerAddrStats = ServerAddrStats <$> TM.emptyIO <*> newIORef (M.fromList $ map (\c -> (c, emptyHistogram c)) [minBound .. maxBound])
-  where
-    emptyHistogram c = AddrHistogram {bucketCounts = map (const 0) (counterBounds c), countSum = 0, addressCount = 0, periodMax = 0}
-
-newAddrStats :: AddrCounter c => IO (AddrStats c)
-newAddrStats = AddrStats <$> newTVarIO 0 <*> newCells <*> newCells
-  where
-    newCells = M.fromList <$> mapM (\c -> (c,) <$> newIORef 0) [minBound .. maxBound]
-
-withAddrStats :: (AddrCounter c, MonadUnliftIO m) => Maybe (AddrStatsMap c) -> Socket -> (Maybe (AddrStats c) -> m a) -> m a
-withAddrStats m_ sock action = case m_ of
-  Just m ->
-    liftIO (addrKey <$$> tryAny (getPeerName sock)) >>= \case
-      Right (Just k) -> do
-        s <- liftIO $ openAddrStats m k
-        action (Just s) `finally` liftIO (closeAddrStats s)
-      _ -> action Nothing
-  Nothing -> action Nothing
-
-openAddrStats :: AddrCounter c => AddrStatsMap c -> AddrKey -> IO (AddrStats c)
-openAddrStats m k = do
-  new <- maybe newAddrStats pure =<< TM.lookupIO k m
-  s <- atomically $ TM.lookup k m >>= maybe (new <$ TM.insert k new m) pure >>= \entry -> entry <$ modifyTVar' (connectionsCount entry) (+ 1)
-  s <$ incAddrCounter s connectionsCounter
-
-closeAddrStats :: AddrStats c -> IO ()
-closeAddrStats AddrStats {connectionsCount} = atomically $ modifyTVar' connectionsCount (subtract 1)
-
-incAddrCounter :: AddrCounter c => AddrStats c -> c -> IO ()
-incAddrCounter s c = addAddrCounter s c 1
-
-addAddrCounter :: AddrCounter c => AddrStats c -> c -> Int -> IO ()
-addAddrCounter AddrStats {current} c n = forM_ (M.lookup c current) $ \cell -> atomicModifyIORef'_ cell (+ n)
-
-rolloverAddrStats :: AddrCounter c => ServerAddrStats c -> IO ()
-rolloverAddrStats ServerAddrStats {addrStatsMap, addrHistograms} = do
-  entries <- M.toList <$> readTVarIO addrStatsMap
-  closingCounts <- forM entries $ \(k, s) -> do
-    counts <- closePeriod s
-    when (all (== 0) counts) $ atomically $ deleteIdle k s
-    pure counts
-  let periodCounts = M.unionsWith (<>) $ map (M.map (: []) . M.filter (> 0)) closingCounts
-  atomicModifyIORef'_ addrHistograms $ M.mapWithKey $ \c -> addPeriodCounts (counterBounds c) (M.findWithDefault [] c periodCounts)
-  where
-    closePeriod AddrStats {current, previous} = M.traverseWithKey closeCell current
-      where
-        closeCell c cell = do
-          n <- atomicModifyIORef' cell (0,)
-          forM_ (M.lookup c previous) (`writeIORef` n)
-          pure n
-    deleteIdle k AddrStats {connectionsCount} =
-      whenM ((0 ==) <$> readTVar connectionsCount) $ TM.delete k addrStatsMap
-
-addPeriodCounts :: [Int] -> [Int] -> AddrHistogram -> AddrHistogram
-addPeriodCounts bounds ns AddrHistogram {bucketCounts, countSum, addressCount} =
-  AddrHistogram
-    { bucketCounts = zipWith (+) bucketCounts $ scanl1 (+) $ map (\i -> IM.findWithDefault 0 i boundCounts) [0 .. length bounds - 1],
-      countSum = countSum + sum ns,
-      addressCount = addressCount + length ns,
-      periodMax = maximum (0 : ns)
-    }
-  where
-    boundCounts = IM.fromListWith (+) $ map (\n -> (length $ takeWhile (< n) bounds, 1)) ns
-
-addressStatsThread :: AddrCounter c => AddressStatsConfig -> ServerAddrStats c -> IO ()
-addressStatsThread AddressStatsConfig {period} stats = do
-  labelMyThread "addressStatsThread"
-  forever $ threadDelay' (period * 1000000) >> rolloverAddrStats stats
-
-topAddresses :: AddrCounter c => AddrStatsMap c -> c -> Int -> IO [(AddrKey, Int, Int)]
-topAddresses m c n = do
-  entries <- M.toList <$> readTVarIO m
-  counts <- forM entries $ \(k, AddrStats {previous, current}) -> (k,,) <$> cellValue previous <*> cellValue current
-  pure $ take n $ sortOn (\(_, p, cur) -> Down (p + cur)) $ filter (\(_, p, cur) -> p + cur > 0) counts
-  where
-    cellValue = maybe (pure 0) readIORef . M.lookup c
-
-printTopAddresses :: AddrCounter c => Handle -> Maybe (AddrStatsMap c) -> Text -> Maybe Int -> IO ()
-printTopAddresses h m_ name n_ = case m_ of
-  Just m -> case counterByName name of
-    Just c -> do
-      rows <- topAddresses m c (fromMaybe 10 n_)
-      hPutStrLn h "address,previous,current"
-      forM_ rows $ \(k, p, cur) -> T.hPutStrLn h $ addrKeyText k <> "," <> tshow p <> "," <> tshow cur
-    Nothing -> hPutStrLn h "error: unknown counter"
-  Nothing -> hPutStrLn h "error: address statistics are off"
-
-addressesArgsP :: A.Parser (Text, Maybe Int)
-addressesArgsP = (,) <$> (A.space *> (safeDecodeUtf8 <$> A.takeTill (== ' '))) <*> optional (A.space *> A.decimal)
-
-addressesArgs :: Text -> Maybe Int -> ByteString
-addressesArgs name n_ = encodeUtf8 name <> maybe "" ((" " <>) . bshow) n_
-
-addrHistogramMetrics :: AddrCounter c => Text -> Text -> Map c AddrHistogram -> Text
-addrHistogramMetrics prefix tsEpoch histograms =
-  "# Client addresses\n\
-  \# ----------------\n\
-  \\n"
-    <> "# HELP " <> countMetric <> " Counts of client addresses per period\n"
-    <> "# TYPE " <> countMetric <> " histogram\n"
-    <> T.concat (map countLines hs)
-    <> "\n# HELP " <> maxMetric <> " Maximum count of a client address in the last period\n"
-    <> "# TYPE " <> maxMetric <> " gauge\n"
-    <> T.concat (map (\(c, AddrHistogram {periodMax}) -> sample maxMetric c [] periodMax) hs)
-    <> "\n"
-  where
-    hs = M.toList histograms
-    countMetric = prefix <> "_client_address_period_count"
-    maxMetric = prefix <> "_client_address_period_max"
-    countLines (c, AddrHistogram {bucketCounts, countSum, addressCount}) =
-      T.concat (zipWith (\b cnt -> sample (countMetric <> "_bucket") c [("le", tshow b)] cnt) (counterBounds c) bucketCounts)
-        <> sample (countMetric <> "_bucket") c [("le", "+Inf")] addressCount
-        <> sample (countMetric <> "_sum") c [] countSum
-        <> sample (countMetric <> "_count") c [] addressCount
-    sample metric c labels v =
-      metric <> "{" <> T.intercalate "," (map (\(l, lv) -> l <> "=\"" <> lv <> "\"") (("counter", counterName c) : labels)) <> "} " <> tshow v <> " " <> tsEpoch <> "\n"
@@ -44,8 +44,6 @@ module Simplex.Messaging.Server.CLI
    checkSavedFingerprint,
    iniTransports,
    iniDBOptions,
-    iniAddressStats,
-    addressStatsIniContent,
    printServerConfig,
    printServerTransports,
    printSMPServerConfig,
@@ -75,14 +73,13 @@ import Simplex.Messaging.Agent.Store.Postgres.Options (DBOpts (..))
 import Simplex.Messaging.Agent.Store.Shared (MigrationConfirmation (..))
 import Simplex.Messaging.Encoding.String
 import Simplex.Messaging.Protocol (ProtoServerWithAuth (..), ProtocolServer (..), ProtocolTypeI)
-import Simplex.Messaging.Server.AddressStats (AddressStatsConfig (..), defaultAddressStatsPeriod)
 import Simplex.Messaging.Server.Env.STM (ServerStoreCfg (..), StartOptions (..), dbStoreCfg, storeLogFile')
 import Simplex.Messaging.Server.Main.GitCommit
 import Simplex.Messaging.Server.QueueStore.Postgres.Config (PostgresStoreCfg (..))
 import Simplex.Messaging.Transport (ASrvTransport, ATransport (..), TLS, Transport (..), simplexMQVersion)
 import Simplex.Messaging.Transport.Server (AddHTTP, loadFileFingerprint)
 import Simplex.Messaging.Transport.WebSockets (WS)
-import Simplex.Messaging.Util (eitherToMaybe, tshow, whenM)
+import Simplex.Messaging.Util (eitherToMaybe, whenM)
 import System.Directory (doesDirectoryExist, listDirectory, removeDirectoryRecursive, removePathForcibly)
 import System.Environment (lookupEnv)
 import System.Exit (exitFailure)
@@ -438,19 +435,6 @@ iniDBOptions ini _default@DBOpts {connstr, schema, poolSize} =
      createSchema = False
    }

-iniAddressStats :: Ini -> Maybe AddressStatsConfig
-iniAddressStats ini =
-  AddressStatsConfig {period = readIniDefault defaultAddressStatsPeriod "ADDRESS_STATS" "period" ini}
-    <$ settingIsOn "ADDRESS_STATS" "enable" ini
-
-addressStatsIniContent :: Text
-addressStatsIniContent =
-  "[ADDRESS_STATS]\n\
-  \# Command counts per client address, shown by the control port command `addresses`\n\
-  \# and aggregated in Prometheus metrics.\n\
-  \enable = off\n"
-    <> ("period = " <> tshow defaultAddressStatsPeriod <> "\n")
-
 printServerConfig :: String -> [(ServiceName, ASrvTransport, AddHTTP)] -> Maybe FilePath -> IO ()
 printServerConfig protocol transports logFile = do
  putStrLn $ case logFile of
@@ -7,10 +7,8 @@ module Simplex.Messaging.Server.Control
  ) where

 import qualified Data.Attoparsec.ByteString.Char8 as A
-import Data.Text (Text)
 import Simplex.Messaging.Encoding.String
 import Simplex.Messaging.Protocol (BasicAuth, BlockingInfo, SenderId)
-import Simplex.Messaging.Server.AddressStats (addressesArgs, addressesArgsP)

 data CPClientRole = CPRNone | CPRUser | CPRAdmin
  deriving (Eq, Show)
@@ -30,7 +28,6 @@ data ControlProtocol
  | CPStatus SenderId
  | CPBlock SenderId BlockingInfo
  | CPUnblock SenderId
-  | CPAddresses Text (Maybe Int)
  | CPSave
  | CPHelp
  | CPQuit
@@ -52,7 +49,6 @@ instance StrEncoding ControlProtocol where
    CPStatus sId -> "status " <> strEncode sId
    CPBlock sId info -> "block " <> strEncode sId <> " " <> strEncode info
    CPUnblock sId -> "unblock " <> strEncode sId
-    CPAddresses name n_ -> "addresses " <> addressesArgs name n_
    CPSave -> "save"
    CPHelp -> "help"
    CPQuit -> "quit"
@@ -73,7 +69,6 @@ instance StrEncoding ControlProtocol where
      "status" -> CPStatus <$> _strP
      "block" -> CPBlock <$> _strP <*> _strP
      "unblock" -> CPUnblock <$> _strP
-      "addresses" -> uncurry CPAddresses <$> addressesArgsP
      "save" -> pure CPSave
      "help" -> pure CPHelp
      "quit" -> pure CPQuit
@@ -31,8 +31,6 @@ module Simplex.Messaging.Server.Env.STM
    SubscribedClients,
    ProxyAgent (..),
    Client (..),
-    SMPAddrCounter (..),
-    smpCmdCounter,
    ClientId,
    ClientSub (..),
    Sub (..),
@@ -70,6 +68,7 @@ module Simplex.Messaging.Server.Env.STM
    defaultInactiveClientExpiration,
    defaultProxyClientConcurrency,
    defaultNameResolverConcurrency,
+    defaultAuthErrorDelayMs,
    defaultMaxJournalMsgCount,
    defaultMaxJournalStateLines,
    defaultIdleQueueInterval,
@@ -113,7 +112,6 @@ import Simplex.Messaging.Client.Agent (SMPClientAgent, SMPClientAgentConfig, new
 import Simplex.Messaging.Crypto (KeyHash (..))
 import qualified Simplex.Messaging.Crypto as C
 import Simplex.Messaging.Protocol
-import Simplex.Messaging.Server.AddressStats (AddrCounter (..), AddrStats, AddressStatsConfig, ServerAddrStats, newServerAddrStats)
 import Simplex.Messaging.Server.Expiration
 import Simplex.Messaging.Server.Information
 import Simplex.Messaging.Server.MsgStore.Journal
@@ -186,11 +184,11 @@ data ServerConfig s = ServerConfig
    -- | interval and file to save prometheus metrics
    prometheusInterval :: Maybe Int,
    prometheusMetricsFile :: FilePath,
-    addressStats :: Maybe AddressStatsConfig,
    -- | notification delivery interval
    ntfDeliveryInterval :: Int,
    -- | interval between sending pending END events to unsubscribed clients, seconds
    pendingENDInterval :: Int,
+    authErrorDelay :: Int64,
    smpCredentials :: ServerCredentials,
    httpCredentials :: Maybe ServerCredentials,
    -- | SMP client-server protocol version range
@@ -259,6 +257,9 @@ defaultProxyClientConcurrency = 32
 defaultNameResolverConcurrency :: Int
 defaultNameResolverConcurrency = 1000

+defaultAuthErrorDelayMs :: Int64
+defaultAuthErrorDelayMs = 50
+
 journalMsgStoreDepth :: Int
 journalMsgStoreDepth = 5

@@ -289,8 +290,7 @@ data Env s = Env
    sockets :: TVar [(ServiceName, SocketState)],
    clientSeq :: TVar ClientId,
    proxyAgent :: ProxyAgent, -- senders served on this proxy
-    namesEnv :: Maybe NamesEnv, -- public-namespace resolver, present when [NAMES] enable: on
-    addrStats :: Maybe (ServerAddrStats SMPAddrCounter)
+    namesEnv :: Maybe NamesEnv -- public-namespace resolver, present when [NAMES] enable: on
  }

 msgStore :: Env s -> s
@@ -470,117 +470,9 @@ data Client s = Client
    connected :: TVar Bool,
    createdAt :: SystemTime,
    rcvActiveAt :: TVar SystemTime,
-    sndActiveAt :: TVar SystemTime,
-    clientAddrStats :: Maybe (AddrStats SMPAddrCounter)
+    sndActiveAt :: TVar SystemTime
  }

-data SMPAddrCounter
-  = SACConnections
-  | SACErrors
-  | SACNew
-  | SACSub
-  | SACSubs
-  | SACKey
-  | SACRKey
-  | SACLSet
-  | SACLDel
-  | SACNKey
-  | SACNDel
-  | SACGet
-  | SACAck
-  | SACOff
-  | SACDel
-  | SACQue
-  | SACSKey
-  | SACSend
-  | SACPing
-  | SACLKey
-  | SACLGet
-  | SACNSub
-  | SACNSubs
-  | SACPrxy
-  | SACPfwd
-  | SACRfwd
-  | SACRslv
-  | SACPrxyOwn
-  | SACPrxyConnected
-  | SACPrxyNew
-  | SACPrxyOnion
-  | SACPrxyFailed
-  | SACPfwdOwn
-  | SACPfwdOther
-  | SACPfwdOnion
-  | SACPfwdFailed
-  deriving (Eq, Ord, Enum, Bounded, Show)
-
-instance AddrCounter SMPAddrCounter where
-  counterName = \case
-    SACConnections -> "connections"
-    SACErrors -> "errors"
-    SACNew -> "NEW"
-    SACSub -> "SUB"
-    SACSubs -> "SUBS"
-    SACKey -> "KEY"
-    SACRKey -> "RKEY"
-    SACLSet -> "LSET"
-    SACLDel -> "LDEL"
-    SACNKey -> "NKEY"
-    SACNDel -> "NDEL"
-    SACGet -> "GET"
-    SACAck -> "ACK"
-    SACOff -> "OFF"
-    SACDel -> "DEL"
-    SACQue -> "QUE"
-    SACSKey -> "SKEY"
-    SACSend -> "SEND"
-    SACPing -> "PING"
-    SACLKey -> "LKEY"
-    SACLGet -> "LGET"
-    SACNSub -> "NSUB"
-    SACNSubs -> "NSUBS"
-    SACPrxy -> "PRXY"
-    SACPfwd -> "PFWD"
-    SACRfwd -> "RFWD"
-    SACRslv -> "RSLV"
-    SACPrxyOwn -> "PRXY_own"
-    SACPrxyConnected -> "PRXY_connected"
-    SACPrxyNew -> "PRXY_new"
-    SACPrxyOnion -> "PRXY_onion"
-    SACPrxyFailed -> "PRXY_failed"
-    SACPfwdOwn -> "PFWD_own"
-    SACPfwdOther -> "PFWD_other"
-    SACPfwdOnion -> "PFWD_onion"
-    SACPfwdFailed -> "PFWD_failed"
-  connectionsCounter = SACConnections
-
-smpCmdCounter :: Cmd -> SMPAddrCounter
-smpCmdCounter (Cmd _ cmd) = case cmd of
-  NEW _ -> SACNew
-  SUB -> SACSub
-  SUBS {} -> SACSubs
-  KEY _ -> SACKey
-  RKEY _ -> SACRKey
-  LSET {} -> SACLSet
-  LDEL -> SACLDel
-  NKEY {} -> SACNKey
-  NDEL -> SACNDel
-  GET -> SACGet
-  ACK _ -> SACAck
-  OFF -> SACOff
-  DEL -> SACDel
-  QUE -> SACQue
-  SKEY _ -> SACSKey
-  SEND {} -> SACSend
-  PING -> SACPing
-  LKEY _ -> SACLKey
-  LGET -> SACLGet
-  NSUB -> SACNSub
-  NSUBS {} -> SACNSubs
-  PRXY {} -> SACPrxy
-  PFWD {} -> SACPfwd
-  RFWD _ -> SACRfwd
-  RSLV _ -> SACRslv
-
 type VerifiedTransmission s = (Maybe (StoreQueue s, QueueRec), Transmission Cmd)

 type ResponseAndMessage = (Transmission BrokerMsg, Maybe (Transmission BrokerMsg))
@@ -633,8 +525,8 @@ newServerSubscribers = do
  pendingEvents <- newTVarIO IM.empty
  pure ServerSubscribers {subQ, queueSubscribers, serviceSubscribers, totalServiceSubs, subClients, pendingEvents}

-newClient :: ClientId -> Natural -> THandleParams SMPVersion 'TServer -> SystemTime -> Maybe (AddrStats SMPAddrCounter) -> IO (Client s)
-newClient clientId qSize clientTHParams createdAt clientAddrStats = do
+newClient :: ClientId -> Natural -> THandleParams SMPVersion 'TServer -> SystemTime -> IO (Client s)
+newClient clientId qSize clientTHParams createdAt = do
  subscriptions <- TM.emptyIO
  ntfSubscriptions <- TM.emptyIO
  serviceSubscribed <- newTVarIO False
@@ -669,8 +561,7 @@ newClient clientId qSize clientTHParams createdAt clientAddrStats = do
        connected,
        createdAt,
        rcvActiveAt,
-        sndActiveAt,
-        clientAddrStats
+        sndActiveAt
      }

 newSubscription :: SubscriptionThread -> STM Sub
@@ -685,7 +576,10 @@ newProhibitedSub = do
  return Sub {subThread = ProhibitSub, delivered}

 newEnv :: ServerConfig s -> IO (Env s)
-newEnv config@ServerConfig {smpCredentials, httpCredentials, serverStoreCfg, smpAgentCfg, information, messageExpiration, idleQueueInterval, msgQueueQuota, maxJournalMsgCount, maxJournalStateLines, namesConfig, addressStats} = do
+newEnv config@ServerConfig {smpCredentials, httpCredentials, serverStoreCfg, smpAgentCfg, information, messageExpiration, idleQueueInterval, msgQueueQuota, maxJournalMsgCount, maxJournalStateLines, namesConfig, msgIdBytes} = do
+  when (msgIdBytes < 24) $ do
+    logError "Error: msgIdBytes must be at least 24"
+    exitFailure
  serverActive <- newTVarIO True
  server <- newServer
  msgStore_ <- case serverStoreCfg of
@@ -740,7 +634,6 @@ newEnv config@ServerConfig {smpCredentials, httpCredentials, serverStoreCfg, smp
      Right _ -> logInfo "[NAMES] endpoint probe ok"
      Left e -> logWarn $ "[NAMES] endpoint probe failed (server will still start, RSLV will return ERR (NAME ...) until reachable): " <> tshow e
    pure env
-  addrStats <- mapM (const newServerAddrStats) addressStats
  pure
    Env
      { serverActive,
@@ -757,8 +650,7 @@ newEnv config@ServerConfig {smpCredentials, httpCredentials, serverStoreCfg, smp
        sockets,
        clientSeq,
        proxyAgent,
-        namesEnv,
-        addrStats
+        namesEnv
      }
  where
    loadStoreLog :: StoreQueueClass q => (RecipientId -> QueueRec -> IO q) -> FilePath -> STMQueueStore q -> IO ()
@@ -578,9 +578,9 @@ smpServerCLI_ generateSite serveStaticFiles attachStaticFiles cfgPath logPath =
              serverStatsBackupFile = logStats $> combine logPath "smp-server-stats.log",
              prometheusInterval = eitherToMaybe (lookupValue "STORE_LOG" "prometheus_interval" ini) >>= readMaybe . T.unpack,
              prometheusMetricsFile = combine logPath "smp-server-metrics.txt",
-              addressStats = iniAddressStats ini,
              pendingENDInterval = 15000000, -- 15 seconds
              ntfDeliveryInterval = 1500000, -- 1.5 second
+              authErrorDelay = 1000 * readIniDefault defaultAuthErrorDelayMs "TRANSPORT" "auth_error_delay_ms" ini,
              smpServerVRange = supportedServerSMPRelayVRange,
              transportConfig =
                mkTransportServerConfig
@@ -25,7 +25,7 @@ import Network.Socket (HostName)
 import Simplex.Messaging.Agent.Store.Postgres.Options (DBOpts (..))
 import Simplex.Messaging.Encoding.String
 import Simplex.Messaging.Protocol (BasicAuth)
-import Simplex.Messaging.Server.CLI (SignAlgorithm, addressStatsIniContent, onOff)
+import Simplex.Messaging.Server.CLI (SignAlgorithm, onOff)
 import Simplex.Messaging.Server.Env.STM
 import Simplex.Messaging.Server.Expiration (ExpirationConfig (..))
 import Simplex.Messaging.Server.Information (Entity (..), ServerPublicInfo (..))
@@ -130,7 +130,9 @@ iniFileContent cfgPath logPath opts host basicAuth controlPortPwds =
    <> ("host = " <> T.pack host <> "\n")
    <> ("port = " <> defaultServerPorts <> "\n")
    <> "log_tls_errors = off\n\n\
-        \# Use `websockets = 443` to run websockets server in addition to plain TLS.\n\
+        \# Minimum time to respond with AUTH error, milliseconds.\n"
+    <> ("# auth_error_delay_ms = " <> tshow defaultAuthErrorDelayMs <> "\n\n")
+    <> "# Use `websockets = 443` to run websockets server in addition to plain TLS.\n\
        \# This option is deprecated and should be used for testing only.\n\
        \# , port 443 should be specified in port above\n\
        \websockets = off\n"
@@ -176,9 +178,7 @@ iniFileContent cfgPath logPath opts host basicAuth controlPortPwds =
        \disconnect = on\n"
    <> ("ttl = " <> tshow (ttl defaultInactiveClientExpiration) <> "\n")
    <> ("check_interval = " <> tshow (checkInterval defaultInactiveClientExpiration))
-    <> "\n\n"
-    <> addressStatsIniContent
-    <> "\n\
+    <> "\n\n\
        \[WEB]\n\
        \# Set path to generate static mini-site for server information and qr codes/links\n"
    <> ("static_path = " <> T.pack (fromMaybe defaultStaticPath webStaticPath) <> "\n\n")
@@ -114,7 +114,9 @@ instance MsgStoreClass PostgresMsgStore where
    where
      st = dbStore $ queueStore_ ms
      oldMsg = now - ttl
-      batchSize = 10000 :: Int
+      -- expired messages read per page in expire_old_messages, and the page is one
+      -- transaction: queues in it stay row-locked against SEND and ACK until it commits.
+      batchSize = 100 :: Int
      toMessageStats (expiredMsgsCount, storedMsgsCount, storedQueues) =
        MessageStats {expiredMsgsCount, storedMsgsCount, storedQueues}

@@ -200,7 +202,7 @@ instance MsgStoreClass PostgresMsgStore where
          DB.query
            db
            "SELECT quota_written, was_empty FROM write_message(?,?,?,?,?,?,?)"
-            (recipientId' q, Binary (messageId msg), systemSeconds (messageTs msg), msgQuota, ntf, Binary body, quota)
+            (recipientId' q, messageId msg, systemSeconds (messageTs msg), msgQuota, ntf, Binary body, quota)
    where
      toResult = \case
        ((msgQuota, wasEmpty) : _) -> if msgQuota then Nothing else Just (msg, wasEmpty)
@@ -269,14 +271,14 @@ instance MsgStoreClass PostgresMsgStore where
    uninterruptibleMask_ $
      withDB' "tryDelMsg" (queueStore_ ms) $ \db ->
        maybeFirstRow toMessage $
-          DB.query db "SELECT r_msg_id, r_msg_ts, r_msg_quota, r_msg_ntf_flag, r_msg_body FROM try_del_msg(?, ?)" (recipientId' q, Binary msgId)
+          DB.query db "SELECT r_msg_id, r_msg_ts, r_msg_quota, r_msg_ntf_flag, r_msg_body FROM try_del_msg(?, ?)" (recipientId' q, msgId)

  tryDelPeekMsg :: PostgresMsgStore -> PostgresQueue -> MsgId -> ExceptT ErrorType IO (Maybe Message, Maybe Message)
  tryDelPeekMsg ms q msgId =
    uninterruptibleMask_ $
      withDB' "tryDelPeekMsg" (queueStore_ ms) $ \db ->
        toResult . map toMessage
-          <$> DB.query db "SELECT r_msg_id, r_msg_ts, r_msg_quota, r_msg_ntf_flag, r_msg_body FROM try_del_peek_msg(?, ?)" (recipientId' q, Binary msgId)
+          <$> DB.query db "SELECT r_msg_id, r_msg_ts, r_msg_quota, r_msg_ntf_flag, r_msg_body FROM try_del_peek_msg(?, ?)" (recipientId' q, msgId)
    where
      toResult = \case
        [] -> (Nothing, Nothing)
@@ -295,13 +297,13 @@ uninterruptibleMask_ :: ExceptT ErrorType IO a -> ExceptT ErrorType IO a
 uninterruptibleMask_ = ExceptT . E.uninterruptibleMask_ . runExceptT
 {-# INLINE uninterruptibleMask_ #-}

-toMaybeMessage :: (Maybe (Binary MsgId), Maybe Int64, Maybe Bool, Maybe Bool, Maybe (Binary MsgBody)) -> Maybe Message
+toMaybeMessage :: (Maybe MsgId, Maybe Int64, Maybe Bool, Maybe Bool, Maybe (Binary MsgBody)) -> Maybe Message
 toMaybeMessage = \case
  (Just msgId, Just ts, Just msgQuota, Just ntf, Just body) -> Just $ toMessage (msgId, ts, msgQuota, ntf, body)
  _ -> Nothing

-toMessage :: (Binary MsgId, Int64, Bool, Bool, Binary MsgBody) -> Message
-toMessage (Binary msgId, ts, msgQuota, ntf, Binary body)
+toMessage :: (MsgId, Int64, Bool, Bool, Binary MsgBody) -> Message
+toMessage (msgId, ts, msgQuota, ntf, Binary body)
  | msgQuota = MessageQuota {msgId, msgTs}
  | otherwise = Message {msgId, msgTs, msgFlags = MsgFlags ntf, msgBody = C.unsafeMaxLenBS body} -- TODO [messages] unsafeMaxLenBS?
  where
@@ -363,8 +365,8 @@ deleteAllMessages ms =
      db
      [sql|
        UPDATE msg_queues
-        SET msg_queue_size = 0, msg_can_write = TRUE, msg_queue_expire = FALSE
-        WHERE msg_queue_size != 0 OR msg_can_write = FALSE OR msg_queue_expire = TRUE
+        SET msg_queue_size = 0, msg_can_write = TRUE
+        WHERE msg_queue_size != 0 OR msg_can_write = FALSE
      |]

 updateQueueCounts :: PostgresMsgStore -> IO ()
@@ -384,16 +386,15 @@ updateQueueCounts ms =
      db
      [sql|
        UPDATE msg_queues
-        SET msg_queue_size = 0, msg_can_write = TRUE, msg_queue_expire = FALSE
-        WHERE msg_queue_size != 0 OR msg_can_write = FALSE OR msg_queue_expire = TRUE
+        SET msg_queue_size = 0, msg_can_write = TRUE
+        WHERE msg_queue_size != 0 OR msg_can_write = FALSE
      |]
    void $ DB.execute_
      db
      [sql|
        UPDATE msg_queues q
        SET msg_queue_size = s.size,
-            msg_can_write = s.quota_count = 0,
-            msg_queue_expire = s.size > s.quota_count
+            msg_can_write = s.quota_count = 0
        FROM queue_stats s
        WHERE q.recipient_id = s.recipient_id
      |]
@@ -428,7 +429,7 @@ messageRecToText rId msg =
    tabFields = BB.char7 ',' `intersperse` fields
    fields =
      [ renderField (toField rId),
-        renderField (toField $ Binary (messageId msg)),
+        renderField (toField $ messageId msg),
        renderField (toField $ systemSeconds (messageTs msg)),
        renderField (toField msgQuota),
        renderField (toField ntf),
@@ -14,15 +14,12 @@ module Simplex.Messaging.Server.Prometheus
 import Data.Int (Int64)
 import qualified Data.IntMap.Strict as IM
 import Data.List (mapAccumL)
-import Data.Map.Strict (Map)
 import Data.Text (Text)
 import qualified Data.Text as T
 import Data.Time.Clock (UTCTime (..), diffUTCTime)
 import Data.Time.Clock.System (systemEpochDay)
 import Data.Time.Format.ISO8601 (iso8601Show)
 import Network.Socket (ServiceName)
-import Simplex.Messaging.Server.AddressStats (AddrHistogram, addrHistogramMetrics)
-import Simplex.Messaging.Server.Env.STM (SMPAddrCounter)
 import Simplex.Messaging.Server.MsgStore.Types (LoadedQueueCounts (..))
 import Simplex.Messaging.Server.QueueStore.Types (EntityCounts (..))
 import Simplex.Messaging.Server.Stats
@@ -49,8 +46,7 @@ data RealTimeMetrics = RealTimeMetrics
    deliveredTimes :: TimeBuckets,
    smpSubs :: RTSubscriberMetrics,
    ntfSubs :: RTSubscriberMetrics,
-    loadedCounts :: LoadedQueueCounts,
-    addressHistograms :: Maybe (Map SMPAddrCounter AddrHistogram)
+    loadedCounts :: LoadedQueueCounts
  }

 data RTSubscriberMetrics = RTSubscriberMetrics
@@ -63,7 +59,7 @@ data RTSubscriberMetrics = RTSubscriberMetrics
 {-# FOURMOLU_DISABLE\n#-}
 prometheusMetrics :: ServerMetrics -> RealTimeMetrics -> UTCTime -> Text
 prometheusMetrics sm rtm ts =
-  time <> queues <> subscriptions <> messages <> ntfMessages <> ntfs <> relays <> services <> names <> clientAddresses <> info
+  time <> queues <> subscriptions <> messages <> ntfMessages <> ntfs <> relays <> services <> names <> info
  where
    ServerMetrics {statsData, activeQueueCounts = ps, activeNtfCounts = psNtf, entityCounts, rtsOptions} = sm
    RealTimeMetrics
@@ -74,8 +70,7 @@ prometheusMetrics sm rtm ts =
        deliveredTimes,
        smpSubs,
        ntfSubs,
-        loadedCounts,
-        addressHistograms
+        loadedCounts
      } = rtm
    ServerStatsData
      { _fromTime,
@@ -131,6 +126,7 @@ prometheusMetrics sm rtm ts =
        _ntfServices,
        _rcvServicesSubMsg,
        _rcvServicesSubDuplicate,
+        _authDelayExceeded,
        _qCount,
        _msgCount,
        _ntfCount,
@@ -197,6 +193,10 @@ prometheusMetrics sm rtm ts =
      \# HELP simplex_smp_queues_notify_monthly Monthly active queues with notifications.\n\
      \# TYPE simplex_smp_queues_notify_monthly gauge\n\
      \simplex_smp_queues_notify_monthly " <> mstr (monthCount psNtf) <> "\n# monthCountNtf\n\
+      \\n\
+      \# HELP simplex_smp_auth_delay_exceeded Responses with AUTH errors sent without delay, as processing took longer than the delay.\n\
+      \# TYPE simplex_smp_auth_delay_exceeded counter\n\
+      \simplex_smp_auth_delay_exceeded " <> mshow _authDelayExceeded <> "\n# authDelayExceeded\n\
      \\n"
    subscriptions =
      "# Subscriptions\n\
@@ -490,7 +490,6 @@ prometheusMetrics sm rtm ts =
          \# TYPE simplex_smp_names_disabled counter\n\
          \simplex_smp_names_disabled " <> mshow _rslvDisabled <> "\n# rslvDisabled\n\
          \\n"
-    clientAddresses = maybe "" (addrHistogramMetrics "simplex_smp" $ tsEpoch ts) addressHistograms
    info =
      "# Info\n\
      \# ----\n\
@@ -13,12 +13,14 @@ module Simplex.Messaging.Server.QueueStore
    ServiceRec (..),
    CertFingerprint,
    ServerEntityStatus (..),
+    isSecuredMsgQueue,
  ) where

 import Control.Applicative (optional, (<|>))
 import qualified Data.ByteString.Char8 as B
 import Data.Functor (($>))
 import Data.List.NonEmpty (NonEmpty)
+import Data.Maybe (isJust)
 import qualified Data.X509 as X
 import qualified Data.X509.Validation as XV
 import Simplex.Messaging.Encoding
@@ -48,6 +50,11 @@ data QueueRec = QueueRec
  }
  deriving (Show)

+isSecuredMsgQueue :: QueueRec -> Bool
+isSecuredMsgQueue QueueRec {queueMode, senderKey} = case queueMode of
+  Just QMContact -> False
+  _ -> isJust senderKey
+
 data NtfCreds = NtfCreds
  { notifierId :: NotifierId,
    notifierKey :: NtfPublicAuthKey,
@@ -314,9 +314,9 @@ instance StoreQueueClass q => QueueStoreClass q (PostgresQueueStore q) where
  addQueueLinkData st sq lnkId d =
    withQueueRec sq "addQueueLinkData" $ \q -> case queueData q of
      Nothing ->
-        addLink q $ \db -> DB.execute db qry (d :. (lnkId, rId))
+        addLink q $ \db -> DB.execute db qry (d :. (lnkId, rId, QMContact))
      Just (lnkId', _) | lnkId' == lnkId ->
-        addLink q $ \db -> DB.execute db (qry <> " AND (fixed_data IS NULL OR fixed_data = ?)") (d :. (lnkId, rId, fst d))
+        addLink q $ \db -> DB.execute db (qry <> " AND (fixed_data IS NULL OR fixed_data = ?)") (d :. (lnkId, rId, QMContact, fst d))
      _ -> throwE AUTH
    where
      rId = recipientId sq
@@ -324,7 +324,8 @@ instance StoreQueueClass q => QueueStoreClass q (PostgresQueueStore q) where
        assertUpdated $ withDB' "addQueueLinkData" st update
        atomically $ writeTVar (queueRec sq) $ Just q {queueData = Just (lnkId, d)}
        withLog "addQueueLinkData" st $ \s -> logCreateLink s rId lnkId d
-      qry = "UPDATE msg_queues SET fixed_data = ?, user_data = ?, link_id = ? WHERE recipient_id = ? AND deleted_at IS NULL"
+      -- the sender key condition is checked in SQL because without cache each command reads its own copy of the queue record
+      qry = "UPDATE msg_queues SET fixed_data = ?, user_data = ?, link_id = ? WHERE recipient_id = ? AND deleted_at IS NULL AND (sender_key IS NULL OR queue_mode = ?)"

  deleteQueueLinkData :: PostgresQueueStore q -> q -> IO (Either ErrorType ())
  deleteQueueLinkData st sq =
@@ -824,6 +825,10 @@ instance ToField EncDataBytes where toField (EncDataBytes s) = toField (Binary s

 deriving newtype instance FromField EncDataBytes

+instance ToField MsgId where toField = toField . Binary . unMsgId
+
+instance FromField MsgId where fromField = blobFieldDecoder mkMsgId
+
 deriving newtype instance ToField (RoundedSystemTime t)

 deriving newtype instance FromField (RoundedSystemTime t)
@@ -22,7 +22,8 @@ serverSchemaMigrations =
    ("20250903_store_messages", m20250903_store_messages, Just down_m20250903_store_messages),
    ("20250915_queue_ids_hash", m20250915_queue_ids_hash, Just down_m20250915_queue_ids_hash),
    ("20260916_prometheus_indexes", m20260916_prometheus_indexes, Just down_m20260916_prometheus_indexes),
-    ("20260917_msg_queues_hot", m20260917_msg_queues_hot, Just down_m20260917_msg_queues_hot)
+    ("20260917_msg_queues_hot", m20260917_msg_queues_hot, Just down_m20260917_msg_queues_hot),
+    ("20260918_expire_messages", m20260918_expire_messages, Just down_m20260918_expire_messages)
  ]

 -- | The list of migrations in ascending order by date
@@ -734,3 +735,504 @@ ALTER TABLE msg_queues RESET (fillfactor, autovacuum_vacuum_scale_factor, autova
 ALTER TABLE messages RESET (autovacuum_vacuum_scale_factor, autovacuum_analyze_scale_factor, toast.autovacuum_vacuum_scale_factor);
 ALTER TABLE services RESET (fillfactor, autovacuum_vacuum_threshold, autovacuum_vacuum_scale_factor);
    |]
+
+m20260918_expire_messages :: Text
+m20260918_expire_messages =
+  [r|
+CREATE INDEX idx_messages_expire ON messages (msg_ts, recipient_id) WHERE NOT msg_quota;
+
+DROP INDEX idx_messages_recipient_id_msg_ts;
+
+DROP INDEX idx_msg_queues_expire;
+
+DROP PROCEDURE expire_old_messages(bigint, integer);
+
+CREATE PROCEDURE expire_old_messages(IN p_old_ts bigint, IN batch_size integer, OUT r_expired_msgs_count bigint, OUT r_stored_msgs_count bigint, OUT r_stored_queues bigint)
+    LANGUAGE plpgsql
+    AS $$
+DECLARE
+  rids BYTEA[];
+  rid BYTEA;
+  last_ts BIGINT := -1;
+  last_rid BYTEA := '\x';
+  next_ts BIGINT;
+  next_rid BYTEA;
+  del_count BIGINT;
+  total_deleted BIGINT := 0;
+BEGIN
+  LOOP
+    -- The page is scanned in (msg_ts, recipient_id) order, so its last row is the next
+    -- keyset cursor. Advancing it past every row read, including queues left unexpired
+    -- because delete_expired_msgs skipped a locked row or raised, is what terminates the
+    -- loop; re-reading from the start instead would repeat those queues forever.
+    SELECT array_agg(DISTINCT recipient_id),
+           (array_agg(msg_ts ORDER BY msg_ts DESC, recipient_id DESC))[1],
+           (array_agg(recipient_id ORDER BY msg_ts DESC, recipient_id DESC))[1]
+    INTO rids, next_ts, next_rid
+    FROM (
+      SELECT msg_ts, recipient_id
+      FROM messages
+      WHERE NOT msg_quota
+        AND msg_ts < p_old_ts
+        AND (msg_ts, recipient_id) > (last_ts, last_rid)
+      ORDER BY msg_ts ASC, recipient_id ASC
+      LIMIT batch_size
+    ) m;
+
+    EXIT WHEN rids IS NULL;
+
+    FOREACH rid IN ARRAY rids
+    LOOP
+      BEGIN
+        del_count := delete_expired_msgs(rid, p_old_ts);
+        total_deleted := total_deleted + del_count;
+      EXCEPTION WHEN OTHERS THEN
+        RAISE WARNING 'STORE, expire_old_messages, error expiring queue %: %', encode(rid, 'base64'), SQLERRM;
+        CONTINUE;
+      END;
+    END LOOP;
+    COMMIT;
+
+    last_ts := next_ts;
+    last_rid := next_rid;
+  END LOOP;
+
+  r_expired_msgs_count := total_deleted;
+  r_stored_msgs_count := (SELECT COUNT(1) FROM messages);
+  r_stored_queues := (SELECT COUNT(1) FROM msg_queues WHERE deleted_at IS NULL);
+END;
+$$;
+
+CREATE OR REPLACE FUNCTION delete_expired_msgs(p_recipient_id bytea, p_old_ts bigint) RETURNS bigint
+    LANGUAGE plpgsql
+    AS $$
+DECLARE
+  q_size BIGINT;
+  keep_min_id BIGINT;
+  del_count BIGINT;
+BEGIN
+  SELECT msg_queue_size INTO q_size
+  FROM msg_queues
+  WHERE recipient_id = p_recipient_id AND deleted_at IS NULL
+  FOR UPDATE SKIP LOCKED;
+
+  IF NOT FOUND OR q_size = 0 THEN
+    RETURN 0;
+  END IF;
+
+  SELECT MIN(message_id) INTO keep_min_id
+  FROM messages WHERE recipient_id = p_recipient_id AND msg_ts >= p_old_ts AND msg_quota = FALSE;
+
+  IF keep_min_id IS NULL THEN
+    DELETE FROM messages WHERE recipient_id = p_recipient_id AND msg_quota = FALSE;
+  ELSE
+    DELETE FROM messages WHERE recipient_id = p_recipient_id AND message_id < keep_min_id AND msg_quota = FALSE;
+  END IF;
+
+  GET DIAGNOSTICS del_count = ROW_COUNT;
+  IF del_count > 0 THEN
+    UPDATE msg_queues
+    SET msg_can_write = msg_can_write OR msg_queue_size <= del_count,
+        msg_queue_size = GREATEST(msg_queue_size - del_count, 0)
+    WHERE recipient_id = p_recipient_id;
+  END IF;
+  RETURN del_count;
+END;
+$$;
+
+CREATE OR REPLACE FUNCTION write_message(p_recipient_id bytea, p_msg_id bytea, p_msg_ts bigint, p_msg_quota boolean, p_msg_ntf_flag boolean, p_msg_body bytea, p_quota integer) RETURNS TABLE(quota_written boolean, was_empty boolean)
+    LANGUAGE plpgsql
+    AS $$
+DECLARE
+  q_can_write BOOLEAN;
+  q_size BIGINT;
+BEGIN
+  SELECT msg_can_write, msg_queue_size INTO q_can_write, q_size
+  FROM msg_queues
+  WHERE recipient_id = p_recipient_id AND deleted_at IS NULL
+  FOR UPDATE;
+
+  IF q_can_write OR q_size = 0 THEN
+    quota_written := p_msg_quota OR q_size >= p_quota;
+    was_empty := q_size = 0;
+
+    INSERT INTO messages(recipient_id, msg_id, msg_ts, msg_quota, msg_ntf_flag, msg_body)
+    VALUES (p_recipient_id, p_msg_id, p_msg_ts, quota_written, p_msg_ntf_flag AND NOT quota_written, CASE WHEN quota_written THEN '' :: BYTEA ELSE p_msg_body END);
+
+    UPDATE msg_queues
+    SET msg_can_write = NOT quota_written,
+        msg_queue_size = msg_queue_size + 1
+    WHERE recipient_id = p_recipient_id;
+
+    RETURN QUERY VALUES (quota_written, was_empty);
+  END IF;
+END;
+$$;
+
+CREATE OR REPLACE FUNCTION try_del_msg(p_recipient_id bytea, p_msg_id bytea) RETURNS TABLE(r_msg_id bytea, r_msg_ts bigint, r_msg_quota boolean, r_msg_ntf_flag boolean, r_msg_body bytea)
+    LANGUAGE plpgsql
+    AS $$
+DECLARE
+  q_size BIGINT;
+  msg RECORD;
+BEGIN
+  SELECT msg_queue_size INTO q_size
+  FROM msg_queues
+  WHERE recipient_id = p_recipient_id AND deleted_at IS NULL
+  FOR UPDATE;
+
+  IF NOT FOUND THEN
+    RETURN;
+  END IF;
+
+  SELECT message_id, msg_id, msg_ts, msg_quota, msg_ntf_flag, msg_body
+  INTO msg
+  FROM messages
+  WHERE recipient_id = p_recipient_id
+  ORDER BY message_id ASC LIMIT 1;
+
+  IF NOT FOUND THEN
+    IF q_size != 0 THEN
+      UPDATE msg_queues
+      SET msg_can_write = TRUE,
+          msg_queue_size = 0
+      WHERE recipient_id = p_recipient_id;
+    END IF;
+    RETURN;
+  END IF;
+
+  IF msg.msg_id = p_msg_id THEN
+    DELETE FROM messages WHERE message_id = msg.message_id;
+    IF FOUND THEN
+      UPDATE msg_queues
+      SET msg_can_write = msg_can_write OR msg_queue_size <= 1,
+          msg_queue_size = GREATEST(msg_queue_size - 1, 0)
+      WHERE recipient_id = p_recipient_id;
+      RETURN QUERY VALUES (msg.msg_id, msg.msg_ts, msg.msg_quota, msg.msg_ntf_flag, msg.msg_body);
+    END IF;
+  END IF;
+END;
+$$;
+
+CREATE OR REPLACE FUNCTION try_del_peek_msg(p_recipient_id bytea, p_msg_id bytea) RETURNS TABLE(r_msg_id bytea, r_msg_ts bigint, r_msg_quota boolean, r_msg_ntf_flag boolean, r_msg_body bytea)
+    LANGUAGE plpgsql
+    AS $$
+DECLARE
+  q_size BIGINT;
+  msg RECORD;
+  msg_deleted BOOLEAN;
+BEGIN
+  SELECT msg_queue_size INTO q_size
+  FROM msg_queues
+  WHERE recipient_id = p_recipient_id AND deleted_at IS NULL
+  FOR UPDATE;
+
+  IF NOT FOUND THEN
+    RETURN;
+  END IF;
+
+  SELECT message_id, msg_id, msg_ts, msg_quota, msg_ntf_flag, msg_body
+  INTO msg
+  FROM messages
+  WHERE recipient_id = p_recipient_id
+  ORDER BY message_id ASC LIMIT 1;
+
+  IF NOT FOUND THEN
+    IF q_size != 0 THEN
+      UPDATE msg_queues
+      SET msg_can_write = TRUE,
+          msg_queue_size = 0
+      WHERE recipient_id = p_recipient_id;
+    END IF;
+    RETURN;
+  END IF;
+
+  IF msg.msg_id = p_msg_id THEN
+    DELETE FROM messages WHERE message_id = msg.message_id;
+
+    msg_deleted := FOUND;
+    IF msg_deleted THEN
+      RETURN QUERY VALUES (msg.msg_id, msg.msg_ts, msg.msg_quota, msg.msg_ntf_flag, msg.msg_body);
+    END IF;
+
+    SELECT msg_id, msg_ts, msg_quota, msg_ntf_flag, msg_body
+    INTO msg
+    FROM messages
+    WHERE recipient_id = p_recipient_id
+    ORDER BY message_id ASC LIMIT 1;
+
+    IF FOUND THEN
+      RETURN QUERY VALUES (msg.msg_id, msg.msg_ts, msg.msg_quota, msg.msg_ntf_flag, msg.msg_body);
+      IF msg_deleted THEN
+        UPDATE msg_queues
+        SET msg_can_write = msg_can_write OR msg_queue_size <= 1,
+            msg_queue_size = GREATEST(msg_queue_size - 1, 0)
+        WHERE recipient_id = p_recipient_id;
+      END IF;
+    ELSIF msg_deleted OR q_size != 0 THEN
+      UPDATE msg_queues
+      SET msg_can_write = TRUE,
+          msg_queue_size = 0
+      WHERE recipient_id = p_recipient_id;
+    END IF;
+  ELSE
+    RETURN QUERY VALUES (msg.msg_id, msg.msg_ts, msg.msg_quota, msg.msg_ntf_flag, msg.msg_body);
+  END IF;
+END;
+$$;
+
+ALTER TABLE msg_queues DROP COLUMN msg_queue_expire;
+    |]
+
+down_m20260918_expire_messages :: Text
+down_m20260918_expire_messages =
+  [r|
+ALTER TABLE msg_queues ADD COLUMN msg_queue_expire boolean NOT NULL DEFAULT FALSE;
+
+-- ADD COLUMN already defaulted every row to FALSE, so the backfill only needs the rows
+-- that become TRUE, which avoids rewriting the whole table. The flag is only read to pick
+-- queues for delete_expired_msgs, and that returns 0 without deleting when msg_queue_size
+-- is 0, so excluding empty queues here cannot change what expires.
+UPDATE msg_queues q
+SET msg_queue_expire = TRUE
+WHERE msg_queue_size > 0
+  AND EXISTS (SELECT 1 FROM messages m WHERE m.recipient_id = q.recipient_id AND NOT m.msg_quota);
+
+CREATE INDEX idx_msg_queues_expire ON msg_queues (recipient_id) WHERE deleted_at IS NULL AND msg_queue_expire;
+
+CREATE INDEX idx_messages_recipient_id_msg_ts ON messages (recipient_id, msg_ts);
+
+DROP INDEX idx_messages_expire;
+
+CREATE OR REPLACE FUNCTION delete_expired_msgs(p_recipient_id bytea, p_old_ts bigint) RETURNS bigint
+    LANGUAGE plpgsql
+    AS $$
+DECLARE
+  q_size BIGINT;
+  keep_min_id BIGINT;
+  del_count BIGINT;
+BEGIN
+  SELECT msg_queue_size INTO q_size
+  FROM msg_queues
+  WHERE recipient_id = p_recipient_id AND deleted_at IS NULL
+  FOR UPDATE SKIP LOCKED;
+
+  IF NOT FOUND OR q_size = 0 THEN
+    RETURN 0;
+  END IF;
+
+  SELECT MIN(message_id) INTO keep_min_id
+  FROM messages WHERE recipient_id = p_recipient_id AND msg_ts >= p_old_ts AND msg_quota = FALSE;
+
+  IF keep_min_id IS NULL THEN
+    DELETE FROM messages WHERE recipient_id = p_recipient_id AND msg_quota = FALSE;
+  ELSE
+    DELETE FROM messages WHERE recipient_id = p_recipient_id AND message_id < keep_min_id AND msg_quota = FALSE;
+  END IF;
+
+  GET DIAGNOSTICS del_count = ROW_COUNT;
+  IF del_count > 0 THEN
+    UPDATE msg_queues
+    SET msg_can_write = msg_can_write OR msg_queue_size <= del_count,
+        msg_queue_expire = msg_queue_size > del_count AND keep_min_id IS NOT NULL,
+        msg_queue_size = GREATEST(msg_queue_size - del_count, 0)
+    WHERE recipient_id = p_recipient_id;
+  END IF;
+  RETURN del_count;
+END;
+$$;
+
+CREATE OR REPLACE FUNCTION write_message(p_recipient_id bytea, p_msg_id bytea, p_msg_ts bigint, p_msg_quota boolean, p_msg_ntf_flag boolean, p_msg_body bytea, p_quota integer) RETURNS TABLE(quota_written boolean, was_empty boolean)
+    LANGUAGE plpgsql
+    AS $$
+DECLARE
+  q_can_write BOOLEAN;
+  q_size BIGINT;
+BEGIN
+  SELECT msg_can_write, msg_queue_size INTO q_can_write, q_size
+  FROM msg_queues
+  WHERE recipient_id = p_recipient_id AND deleted_at IS NULL
+  FOR UPDATE;
+
+  IF q_can_write OR q_size = 0 THEN
+    quota_written := p_msg_quota OR q_size >= p_quota;
+    was_empty := q_size = 0;
+
+    INSERT INTO messages(recipient_id, msg_id, msg_ts, msg_quota, msg_ntf_flag, msg_body)
+    VALUES (p_recipient_id, p_msg_id, p_msg_ts, quota_written, p_msg_ntf_flag AND NOT quota_written, CASE WHEN quota_written THEN '' :: BYTEA ELSE p_msg_body END);
+
+    UPDATE msg_queues
+    SET msg_can_write = NOT quota_written,
+        msg_queue_expire = TRUE,
+        msg_queue_size = msg_queue_size + 1
+    WHERE recipient_id = p_recipient_id;
+
+    RETURN QUERY VALUES (quota_written, was_empty);
+  END IF;
+END;
+$$;
+
+CREATE OR REPLACE FUNCTION try_del_msg(p_recipient_id bytea, p_msg_id bytea) RETURNS TABLE(r_msg_id bytea, r_msg_ts bigint, r_msg_quota boolean, r_msg_ntf_flag boolean, r_msg_body bytea)
+    LANGUAGE plpgsql
+    AS $$
+DECLARE
+  q_size BIGINT;
+  msg RECORD;
+BEGIN
+  SELECT msg_queue_size INTO q_size
+  FROM msg_queues
+  WHERE recipient_id = p_recipient_id AND deleted_at IS NULL
+  FOR UPDATE;
+
+  IF NOT FOUND THEN
+    RETURN;
+  END IF;
+
+  SELECT message_id, msg_id, msg_ts, msg_quota, msg_ntf_flag, msg_body
+  INTO msg
+  FROM messages
+  WHERE recipient_id = p_recipient_id
+  ORDER BY message_id ASC LIMIT 1;
+
+  IF NOT FOUND THEN
+    IF q_size != 0 THEN
+      UPDATE msg_queues
+      SET msg_can_write = TRUE,
+          msg_queue_expire = FALSE,
+          msg_queue_size = 0
+      WHERE recipient_id = p_recipient_id;
+    END IF;
+    RETURN;
+  END IF;
+
+  IF msg.msg_id = p_msg_id THEN
+    DELETE FROM messages WHERE message_id = msg.message_id;
+    IF FOUND THEN
+      UPDATE msg_queues
+      SET msg_can_write = msg_can_write OR msg_queue_size <= 1,
+          msg_queue_expire = msg_queue_size > 1,
+          msg_queue_size = GREATEST(msg_queue_size - 1, 0)
+      WHERE recipient_id = p_recipient_id;
+      RETURN QUERY VALUES (msg.msg_id, msg.msg_ts, msg.msg_quota, msg.msg_ntf_flag, msg.msg_body);
+    END IF;
+  END IF;
+END;
+$$;
+
+CREATE OR REPLACE FUNCTION try_del_peek_msg(p_recipient_id bytea, p_msg_id bytea) RETURNS TABLE(r_msg_id bytea, r_msg_ts bigint, r_msg_quota boolean, r_msg_ntf_flag boolean, r_msg_body bytea)
+    LANGUAGE plpgsql
+    AS $$
+DECLARE
+  q_size BIGINT;
+  msg RECORD;
+  msg_deleted BOOLEAN;
+BEGIN
+  SELECT msg_queue_size INTO q_size
+  FROM msg_queues
+  WHERE recipient_id = p_recipient_id AND deleted_at IS NULL
+  FOR UPDATE;
+
+  IF NOT FOUND THEN
+    RETURN;
+  END IF;
+
+  SELECT message_id, msg_id, msg_ts, msg_quota, msg_ntf_flag, msg_body
+  INTO msg
+  FROM messages
+  WHERE recipient_id = p_recipient_id
+  ORDER BY message_id ASC LIMIT 1;
+
+  IF NOT FOUND THEN
+    IF q_size != 0 THEN
+      UPDATE msg_queues
+      SET msg_can_write = TRUE,
+          msg_queue_expire = FALSE,
+          msg_queue_size = 0
+      WHERE recipient_id = p_recipient_id;
+    END IF;
+    RETURN;
+  END IF;
+
+  IF msg.msg_id = p_msg_id THEN
+    DELETE FROM messages WHERE message_id = msg.message_id;
+
+    msg_deleted := FOUND;
+    IF msg_deleted THEN
+      RETURN QUERY VALUES (msg.msg_id, msg.msg_ts, msg.msg_quota, msg.msg_ntf_flag, msg.msg_body);
+    END IF;
+
+    SELECT msg_id, msg_ts, msg_quota, msg_ntf_flag, msg_body
+    INTO msg
+    FROM messages
+    WHERE recipient_id = p_recipient_id
+    ORDER BY message_id ASC LIMIT 1;
+
+    IF FOUND THEN
+      RETURN QUERY VALUES (msg.msg_id, msg.msg_ts, msg.msg_quota, msg.msg_ntf_flag, msg.msg_body);
+      IF msg_deleted THEN
+        UPDATE msg_queues
+        SET msg_can_write = msg_can_write OR msg_queue_size <= 1,
+            msg_queue_expire = msg_queue_size > 1,
+            msg_queue_size = GREATEST(msg_queue_size - 1, 0)
+        WHERE recipient_id = p_recipient_id;
+      END IF;
+    ELSIF msg_deleted OR q_size != 0 THEN
+      UPDATE msg_queues
+      SET msg_can_write = TRUE,
+          msg_queue_expire = FALSE,
+          msg_queue_size = 0
+      WHERE recipient_id = p_recipient_id;
+    END IF;
+  ELSE
+    RETURN QUERY VALUES (msg.msg_id, msg.msg_ts, msg.msg_quota, msg.msg_ntf_flag, msg.msg_body);
+  END IF;
+END;
+$$;
+
+DROP PROCEDURE expire_old_messages(bigint, integer);
+
+CREATE PROCEDURE expire_old_messages(IN p_old_ts bigint, IN batch_size integer, OUT r_expired_msgs_count bigint, OUT r_stored_msgs_count bigint, OUT r_stored_queues bigint)
+    LANGUAGE plpgsql
+    AS $$
+DECLARE
+  rids BYTEA[];
+  rid BYTEA;
+  last_rid BYTEA := '\x';
+  del_count BIGINT;
+  total_deleted BIGINT := 0;
+BEGIN
+  LOOP
+    SELECT array_agg(recipient_id)
+    INTO rids
+    FROM (
+      SELECT recipient_id
+      FROM msg_queues
+      WHERE deleted_at IS NULL
+        AND msg_queue_expire = TRUE
+        AND recipient_id > last_rid
+      ORDER BY recipient_id ASC
+      LIMIT batch_size
+    ) qs;
+
+    EXIT WHEN rids IS NULL OR cardinality(rids) = 0;
+
+    FOREACH rid IN ARRAY rids
+    LOOP
+      BEGIN
+        del_count := delete_expired_msgs(rid, p_old_ts);
+        total_deleted := total_deleted + del_count;
+      EXCEPTION WHEN OTHERS THEN
+        RAISE WARNING 'STORE, expire_old_messages, error expiring queue %: %', encode(rid, 'base64'), SQLERRM;
+        CONTINUE;
+      END;
+      COMMIT;
+    END LOOP;
+    last_rid := rids[cardinality(rids)];
+  END LOOP;
+
+  r_expired_msgs_count := total_deleted;
+  r_stored_msgs_count := (SELECT COUNT(1) FROM messages);
+  r_stored_queues := (SELECT COUNT(1) FROM msg_queues WHERE deleted_at IS NULL);
+END;
+$$;
+    |]
@@ -47,7 +47,6 @@ BEGIN
  IF del_count > 0 THEN
    UPDATE msg_queues
    SET msg_can_write = msg_can_write OR msg_queue_size <= del_count,
-        msg_queue_expire = msg_queue_size > del_count AND keep_min_id IS NOT NULL,
        msg_queue_size = GREATEST(msg_queue_size - del_count, 0)
    WHERE recipient_id = p_recipient_id;
  END IF;
@@ -63,24 +62,33 @@ CREATE PROCEDURE smp_server.expire_old_messages(IN p_old_ts bigint, IN batch_siz
 DECLARE
  rids BYTEA[];
  rid BYTEA;
+  last_ts BIGINT := -1;
  last_rid BYTEA := '\x';
+  next_ts BIGINT;
+  next_rid BYTEA;
  del_count BIGINT;
  total_deleted BIGINT := 0;
 BEGIN
  LOOP
-    SELECT array_agg(recipient_id)
-    INTO rids
+    -- The page is scanned in (msg_ts, recipient_id) order, so its last row is the next
+    -- keyset cursor. Advancing it past every row read, including queues left unexpired
+    -- because delete_expired_msgs skipped a locked row or raised, is what terminates the
+    -- loop; re-reading from the start instead would repeat those queues forever.
+    SELECT array_agg(DISTINCT recipient_id),
+           (array_agg(msg_ts ORDER BY msg_ts DESC, recipient_id DESC))[1],
+           (array_agg(recipient_id ORDER BY msg_ts DESC, recipient_id DESC))[1]
+    INTO rids, next_ts, next_rid
    FROM (
-      SELECT recipient_id
-      FROM msg_queues
-      WHERE deleted_at IS NULL
-        AND msg_queue_expire = TRUE
-        AND recipient_id > last_rid
-      ORDER BY recipient_id ASC
+      SELECT msg_ts, recipient_id
+      FROM messages
+      WHERE NOT msg_quota
+        AND msg_ts < p_old_ts
+        AND (msg_ts, recipient_id) > (last_ts, last_rid)
+      ORDER BY msg_ts ASC, recipient_id ASC
      LIMIT batch_size
-    ) qs;
+    ) m;

-    EXIT WHEN rids IS NULL OR cardinality(rids) = 0;
+    EXIT WHEN rids IS NULL;

    FOREACH rid IN ARRAY rids
    LOOP
@@ -91,9 +99,11 @@ BEGIN
        RAISE WARNING 'STORE, expire_old_messages, error expiring queue %: %', encode(rid, 'base64'), SQLERRM;
        CONTINUE;
      END;
-      COMMIT;
    END LOOP;
-    last_rid := rids[cardinality(rids)];
+    COMMIT;
+
+    last_ts := next_ts;
+    last_rid := next_rid;
  END LOOP;

  r_expired_msgs_count := total_deleted;
@@ -195,7 +205,6 @@ BEGIN
    IF q_size != 0 THEN
      UPDATE msg_queues
      SET msg_can_write = TRUE,
-          msg_queue_expire = FALSE,
          msg_queue_size = 0
      WHERE recipient_id = p_recipient_id;
    END IF;
@@ -207,7 +216,6 @@ BEGIN
    IF FOUND THEN
      UPDATE msg_queues
      SET msg_can_write = msg_can_write OR msg_queue_size <= 1,
-          msg_queue_expire = msg_queue_size > 1,
          msg_queue_size = GREATEST(msg_queue_size - 1, 0)
      WHERE recipient_id = p_recipient_id;
      RETURN QUERY VALUES (msg.msg_id, msg.msg_ts, msg.msg_quota, msg.msg_ntf_flag, msg.msg_body);
@@ -245,7 +253,6 @@ BEGIN
    IF q_size != 0 THEN
      UPDATE msg_queues
      SET msg_can_write = TRUE,
-          msg_queue_expire = FALSE,
          msg_queue_size = 0
      WHERE recipient_id = p_recipient_id;
    END IF;
@@ -271,14 +278,12 @@ BEGIN
      IF msg_deleted THEN
        UPDATE msg_queues
        SET msg_can_write = msg_can_write OR msg_queue_size <= 1,
-            msg_queue_expire = msg_queue_size > 1,
            msg_queue_size = GREATEST(msg_queue_size - 1, 0)
        WHERE recipient_id = p_recipient_id;
      END IF;
    ELSIF msg_deleted OR q_size != 0 THEN
      UPDATE msg_queues
      SET msg_can_write = TRUE,
-          msg_queue_expire = FALSE,
          msg_queue_size = 0
      WHERE recipient_id = p_recipient_id;
    END IF;
@@ -348,7 +353,6 @@ BEGIN

    UPDATE msg_queues
    SET msg_can_write = NOT quota_written,
-        msg_queue_expire = TRUE,
        msg_queue_size = msg_queue_size + 1
    WHERE recipient_id = p_recipient_id;

@@ -440,7 +444,6 @@ CREATE TABLE smp_server.msg_queues (
    rcv_service_id bytea,
    ntf_service_id bytea,
    msg_can_write boolean DEFAULT true NOT NULL,
-    msg_queue_expire boolean DEFAULT false NOT NULL,
    msg_queue_size bigint DEFAULT 0 NOT NULL
 )
 WITH (fillfactor='80', autovacuum_vacuum_scale_factor='0.02', autovacuum_analyze_scale_factor='0.01', autovacuum_vacuum_cost_limit='1000');
@@ -485,6 +488,10 @@ ALTER TABLE ONLY smp_server.services



+CREATE INDEX idx_messages_expire ON smp_server.messages USING btree (msg_ts, recipient_id) WHERE (NOT msg_quota);
+
+
+
 CREATE INDEX idx_messages_recipient_id_message_id ON smp_server.messages USING btree (recipient_id, message_id);


@@ -493,14 +500,6 @@ CREATE INDEX idx_messages_recipient_id_msg_quota ON smp_server.messages USING bt



-CREATE INDEX idx_messages_recipient_id_msg_ts ON smp_server.messages USING btree (recipient_id, msg_ts);
-
-
-
-CREATE INDEX idx_msg_queues_expire ON smp_server.msg_queues USING btree (recipient_id) WHERE ((deleted_at IS NULL) AND msg_queue_expire);
-
-
-
 CREATE UNIQUE INDEX idx_msg_queues_link_id ON smp_server.msg_queues USING btree (link_id);


@@ -173,6 +173,7 @@ instance StoreQueueClass q => QueueStoreClass q (STMQueueStore q) where
      rId = recipientId sq
      qr = queueRec sq
      add q = case queueData q of
+        _ | isSecuredMsgQueue q -> pure $ Left AUTH
        Nothing -> addLink
        Just (lnkId', d') | lnkId' == lnkId && fst d' == fst d -> addLink
        _ -> pure $ Left AUTH
@@ -128,6 +128,7 @@ data ServerStats = ServerStats
    ntfServices :: ServiceStats,
    rcvServicesSubMsg :: IORef Int,
    rcvServicesSubDuplicate :: IORef Int,
+    authDelayExceeded :: IORef Int,
    qCount :: IORef Int,
    msgCount :: IORef Int,
    ntfCount :: IORef Int,
@@ -190,6 +191,7 @@ data ServerStatsData = ServerStatsData
    _rcvServices :: ServiceStatsData,
    _rcvServicesSubMsg :: Int,
    _rcvServicesSubDuplicate :: Int,
+    _authDelayExceeded :: Int,
    _qCount :: Int,
    _msgCount :: Int,
    _ntfCount :: Int,
@@ -254,6 +256,7 @@ newServerStats ts = do
  ntfServices <- newServiceStats
  rcvServicesSubMsg <- newIORef 0
  rcvServicesSubDuplicate <- newIORef 0
+  authDelayExceeded <- newIORef 0
  qCount <- newIORef 0
  msgCount <- newIORef 0
  ntfCount <- newIORef 0
@@ -315,6 +318,7 @@ newServerStats ts = do
        ntfServices,
        rcvServicesSubMsg,
        rcvServicesSubDuplicate,
+        authDelayExceeded,
        qCount,
        msgCount,
        ntfCount,
@@ -378,6 +382,7 @@ getServerStatsData s = do
  _ntfServices <- getServiceStatsData $ ntfServices s
  _rcvServicesSubMsg <- readIORef $ rcvServicesSubMsg s
  _rcvServicesSubDuplicate <- readIORef $ rcvServicesSubDuplicate s
+  _authDelayExceeded <- readIORef $ authDelayExceeded s
  _qCount <- readIORef $ qCount s
  _msgCount <- readIORef $ msgCount s
  _ntfCount <- readIORef $ ntfCount s
@@ -439,6 +444,7 @@ getServerStatsData s = do
        _ntfServices,
        _rcvServicesSubMsg,
        _rcvServicesSubDuplicate,
+        _authDelayExceeded,
        _qCount,
        _msgCount,
        _ntfCount,
@@ -503,6 +509,7 @@ setServerStats s d = do
  setServiceStats (ntfServices s) $! _ntfServices d
  writeIORef (rcvServicesSubMsg s) $! _rcvServicesSubMsg d
  writeIORef (rcvServicesSubDuplicate s) $! _rcvServicesSubDuplicate d
+  writeIORef (authDelayExceeded s) $! _authDelayExceeded d
  writeIORef (qCount s) $! _qCount d
  writeIORef (msgCount s) $! _msgCount d
  writeIORef (ntfCount s) $! _ntfCount d
@@ -705,6 +712,7 @@ instance StrEncoding ServerStatsData where
          _ntfServices,
          _rcvServicesSubMsg = 0,
          _rcvServicesSubDuplicate = 0,
+          _authDelayExceeded = 0,
          _qCount,
          _msgCount = 0,
          _ntfCount = 0,
@@ -46,7 +46,6 @@ module Simplex.Messaging.Transport
    minServerSMPRelayVersion,
    currentClientSMPRelayVersion,
    currentServerSMPRelayVersion,
-    shortLinksSMPVersion,
    serviceCertsSMPVersion,
    newNtfCredsSMPVersion,
    clientNoticesSMPVersion,
@@ -54,7 +53,7 @@ module Simplex.Messaging.Transport
    namesSMPVersion,
    serverInfoSMPVersion,
    nameAvailSMPVersion,
-    entitlementSMPVersion,
+    fwdNoncesSMPVersion,
    simplexMQVersion,
    smpBlockSize,
    TransportConfig (..),
@@ -137,7 +136,6 @@ import qualified Network.TLS as T
 import qualified Network.TLS.Extra as TE
 import qualified Paths_simplexmq as SMQ
 import qualified Simplex.Messaging.Crypto as C
-import Simplex.Messaging.Crypto.Entitlement (EntitlementProof)
 import Simplex.Messaging.Encoding
 import Simplex.Messaging.Encoding.String
 import Simplex.Messaging.Parsers (dropPrefix, parseRead1, sumTypeJSON)
@@ -179,7 +177,7 @@ smpBlockSize = 16384
 -- 20 - public namespaces resolver, RSLV command (6/20/2026)
 -- 21 - server public information in handshake (7/5/2026)
 -- 22 - RNAME answers name availability as well as the record (7/25/2026)
-- 23 - entitlement proof in client handshake (9/11/2026)
+-- 23 - version in forwarded command nonce, random nonce in forwarded responses (10/2/2026)

 data SMPVersion

@@ -192,11 +190,8 @@ type VersionRangeSMP = VersionRange SMPVersion
 pattern VersionSMP :: Word16 -> VersionSMP
 pattern VersionSMP v = Version v

-_proxyServerHandshakeSMPVersion :: VersionSMP
-_proxyServerHandshakeSMPVersion = VersionSMP 14
-
-shortLinksSMPVersion :: VersionSMP
-shortLinksSMPVersion = VersionSMP 15
+_shortLinksSMPVersion :: VersionSMP
+_shortLinksSMPVersion = VersionSMP 15

 serviceCertsSMPVersion :: VersionSMP
 serviceCertsSMPVersion = VersionSMP 16
@@ -221,14 +216,14 @@ serverInfoSMPVersion = VersionSMP 21
 nameAvailSMPVersion :: VersionSMP
 nameAvailSMPVersion = VersionSMP 22

-entitlementSMPVersion :: VersionSMP
-entitlementSMPVersion = VersionSMP 23
+fwdNoncesSMPVersion :: VersionSMP
+fwdNoncesSMPVersion = VersionSMP 23

 minClientSMPRelayVersion :: VersionSMP
-minClientSMPRelayVersion = VersionSMP 14
+minClientSMPRelayVersion = VersionSMP 15

 minServerSMPRelayVersion :: VersionSMP
-minServerSMPRelayVersion = VersionSMP 14
+minServerSMPRelayVersion = VersionSMP 15

 currentClientSMPRelayVersion :: VersionSMP
 currentClientSMPRelayVersion = VersionSMP 23
@@ -239,13 +234,14 @@ currentServerSMPRelayVersion = VersionSMP 23
 -- Max SMP protocol version to be used in e2e encrypted connection between
 -- client and server, as defined by SMP proxy. Normally set below the current
 -- version to prevent client version fingerprinting by the destination relays
-- when clients upgrade at different times. Set to 22, one below the current
-- version (23): a proxied RSLV carries availability from nameAvailSMPVersion (22),
-- and the entitlement proof of version 23 is never sent via proxy.
+-- when clients upgrade at different times. Pinned to the current version (23)
+-- for this release because forwarded commands use the nonces from
+-- fwdNoncesSMPVersion (23), so the one-version anti-fingerprinting buffer does
+-- not apply yet; it reappears once the current version advances past 23.
 proxiedSMPRelayVersion :: VersionSMP
-proxiedSMPRelayVersion = VersionSMP 22
+proxiedSMPRelayVersion = VersionSMP 23

-- minimal supported protocol version is 14
+-- minimal supported protocol version is 15
 supportedClientSMPRelayVRange :: VersionRangeSMP
 supportedClientSMPRelayVRange = mkVersionRange minClientSMPRelayVersion currentClientSMPRelayVersion

@@ -578,9 +574,7 @@ data SMPClientHandshake = SMPClientHandshake
    -- - notification servers,
    -- - high traffic chat bots,
    -- - high traffic business support clients.
-    clientService :: Maybe SMPClientHandshakeService,
-    -- | proof of the user entitlement bound to the session
-    entitlementProof :: Maybe EntitlementProof
+    clientService :: Maybe SMPClientHandshakeService
  }

 data SMPClientHandshakeService = SMPClientHandshakeService
@@ -598,19 +592,17 @@ data ServiceCredentials = ServiceCredentials
 data SMPServiceRole = SRMessaging | SRNotifier | SRProxy deriving (Eq, Show)

 instance Encoding SMPClientHandshake where
-  smpEncode SMPClientHandshake {smpVersion = v, keyHash, authPubKey, proxyServer, clientService, entitlementProof} =
+  smpEncode SMPClientHandshake {smpVersion = v, keyHash, authPubKey, proxyServer, clientService} =
    smpEncode (v, keyHash)
      <> maybe "" smpEncode authPubKey
      <> smpEncode proxyServer
      <> ifHasService v (smpEncode clientService) ""
-      <> ifHasEntitlement v (smpEncode entitlementProof) ""
  smpP = do
    (v, keyHash) <- smpP
    authPubKey <- optional smpP
    proxyServer <- smpP
    clientService <- ifHasService v smpP (pure Nothing)
-    entitlementProof <- ifHasEntitlement v smpP (pure Nothing)
-    pure SMPClientHandshake {smpVersion = v, keyHash, authPubKey, proxyServer, clientService, entitlementProof}
+    pure SMPClientHandshake {smpVersion = v, keyHash, authPubKey, proxyServer, clientService}

 instance Encoding SMPClientHandshakeService where
  smpEncode SMPClientHandshakeService {serviceRole, serviceCertKey} =
@@ -634,9 +626,6 @@ instance Encoding SMPServiceRole where
 ifHasService :: VersionSMP -> a -> a -> a
 ifHasService v a b = if v >= serviceCertsSMPVersion then a else b

-ifHasEntitlement :: VersionSMP -> a -> a -> a
-ifHasEntitlement v a b = if v >= entitlementSMPVersion then a else b
-
 ifHasServerInfo :: VersionSMP -> a -> a -> a
 ifHasServerInfo v a b = if v >= serverInfoSMPVersion then a else b

@@ -792,8 +781,8 @@ smpServerHandshake srvCert srvSignKey c (k, pk) kh smpVersionRange serverInfoByt
 -- | Client SMP transport handshake.
 --
 -- See https://github.com/simplex-chat/simplexmq/blob/master/protocol/simplex-messaging.md#appendix-a
-smpClientHandshake :: forall c. Transport c => c 'TClient -> Maybe C.KeyPairX25519 -> C.KeyHash -> VersionRangeSMP -> Bool -> Maybe (ServiceCredentials, C.KeyPairEd25519) -> (SessionId -> IO (Maybe EntitlementProof)) -> ExceptT TransportError IO (THandleSMP c 'TClient)
-smpClientHandshake c ks_ keyHash@(C.KeyHash kh) smpVRange proxyServer serviceKeys_ mkEntitlementProof = do
+smpClientHandshake :: forall c. Transport c => c 'TClient -> Maybe C.KeyPairX25519 -> C.KeyHash -> VersionRangeSMP -> Bool -> Maybe (ServiceCredentials, C.KeyPairEd25519) -> ExceptT TransportError IO (THandleSMP c 'TClient)
+smpClientHandshake c ks_ keyHash@(C.KeyHash kh) smpVRange proxyServer serviceKeys_ = do
  SMPServerHandshake {sessionId = sessId, smpVersionRange, authPubKey = certKey@(CertChainPubKey chain exact), serverInfoBytes} <- getHandshake th
  when (sessionId /= sessId) $ throwE TEBadSession
  case smpVersionRange `compatibleVRange` smpVRange of
@@ -810,8 +799,8 @@ smpClientHandshake c ks_ keyHash@(C.KeyHash kh) smpVRange proxyServer serviceKey
            Just sks | v >= serviceVersion (fst sks) && certificateSent c -> Just sks
            _ -> Nothing
          clientService = mkClientService <$> serviceKeys
-      ep <- if v >= entitlementSMPVersion then liftIO (mkEntitlementProof sessionId) else pure Nothing
-      sendHandshake th SMPClientHandshake {smpVersion = v, keyHash, authPubKey = fst <$> ks_, proxyServer, clientService, entitlementProof = ep}
+          hs = SMPClientHandshake {smpVersion = v, keyHash, authPubKey = fst <$> ks_, proxyServer, clientService}
+      sendHandshake th hs
      service <- mapM getClientService serviceKeys
      liftIO $ smpTHandleClient th v vr (snd <$> ks_) ck proxyServer service serverInfoBytes
    Nothing -> throwE TEVersion
@@ -877,7 +866,6 @@ forceCertChain :: CertChainPubKey -> CertChainPubKey
 forceCertChain cert@(CertChainPubKey (X.CertificateChain cc) signedKey) = length (show cc) `seq` show signedKey `seq` cert
 {-# INLINE forceCertChain #-}

-- This function is only used with v >= 8, so currently it's a simple record update.
 -- * Note: it requires updating version-based parameters, to be consistent with smpTHandle_.
 smpTHParamsSetVersion :: VersionSMP -> THandleParams SMPVersion p -> THandleParams SMPVersion p
 smpTHParamsSetVersion v params =
@@ -54,7 +54,7 @@ getHTTP2Server HTTP2ServerConfig {qSize, http2Port, bufferSize, bodyHeadSize, se
  started <- newEmptyTMVarIO
  reqQ <- newTBQueueIO qSize
  action <- async $
-    runHTTP2Server started http2Port bufferSize serverSupported srvCreds Nothing transportConfig Nothing (const $ pure ()) (\_ _ handler -> handler) $ \_sniUsed sessionId sessionALPN r sendResponse -> do
+    runHTTP2Server started http2Port bufferSize serverSupported srvCreds Nothing transportConfig Nothing (const $ pure ()) $ \_sniUsed sessionId sessionALPN r sendResponse -> do
      reqBody <- getHTTP2Body r bodyHeadSize
      atomically $ writeTBQueue reqQ HTTP2Request {sessionId, sessionALPN, request = r, reqBody, sendResponse}
  void . atomically $ takeTMVar started
@@ -63,13 +63,13 @@ getHTTP2Server HTTP2ServerConfig {qSize, http2Port, bufferSize, bodyHeadSize, se
 closeHTTP2Server :: HTTP2Server -> IO ()
 closeHTTP2Server = uninterruptibleCancel . action

-runHTTP2Server :: TMVar Bool -> ServiceName -> BufferSize -> T.Supported -> T.Credential -> Maybe T.Credential -> TransportServerConfig -> Maybe ExpirationConfig -> (SessionId -> IO ()) -> (Socket -> SessionId -> IO () -> IO ()) -> (SNICredentialUsed -> HTTP2ServerFunc) -> IO ()
-runHTTP2Server started port bufferSize srvSupported srvCreds httpCreds_ transportConfig expCfg_ clientFinished withConnection = runHTTP2ServerWith_ expCfg_ clientFinished bufferSize setup
+runHTTP2Server :: TMVar Bool -> ServiceName -> BufferSize -> T.Supported -> T.Credential -> Maybe T.Credential -> TransportServerConfig -> Maybe ExpirationConfig -> (SessionId -> IO ()) -> (SNICredentialUsed -> HTTP2ServerFunc) -> IO ()
+runHTTP2Server started port bufferSize srvSupported srvCreds httpCreds_ transportConfig expCfg_ clientFinished = runHTTP2ServerWith_ expCfg_ clientFinished bufferSize setup
  where
    setup handler = do
      ss <- newSocketState
      let combinedCreds = TLSServerCredential {credential = srvCreds, sniCredential = httpCreds_}
-      runTransportServerState_ ss started port srvSupported combinedCreds transportConfig $ \sock h@(_, tls) -> withConnection sock (tlsUniq tls) (handler h)
+      runTransportServerState_ ss started port srvSupported combinedCreds transportConfig $ \_ -> handler

 -- HTTP2 server can be run on both client and server TLS connections.
 runHTTP2ServerWith :: BufferSize -> ((TLS p -> IO ()) -> a) -> HTTP2ServerFunc -> a
@@ -26,6 +26,7 @@ module Simplex.RemoteControl.Client
    -- for tests only
    sendRCPacket,
    receiveRCPacket,
+    findRCCtrlPairing,
  ) where

 import Control.Applicative ((<|>))
@@ -46,7 +47,7 @@ import Data.List.NonEmpty (NonEmpty (..))
 import qualified Data.List.NonEmpty as L
 import Data.Maybe (isNothing)
 import qualified Data.Text as T
-import Data.Time.Clock.System (getSystemTime)
+import Data.Time.Clock.System (SystemTime (..), getSystemTime)
 import Data.Tuple (swap)
 import Data.Word (Word16)
 import qualified Data.X509 as X
@@ -395,8 +396,10 @@ findRCCtrlPairing :: NonEmpty RCCtrlPairing -> RCEncInvitation -> ExceptT RCErro
 findRCCtrlPairing pairings RCEncInvitation {dhPubKey, nonce, encInvitation} = do
  (pairing, signedInvStr) <- liftEither $ decrypt (L.toList pairings)
  signedInv <- liftEitherWith RCESyntax $ strDecode signedInvStr
-  inv@(RCVerifiedInvitation RCInvitation {dh = invDh}) <- maybe (throwE RCEInvitation) pure $ verifySignedInvitation signedInv
+  inv@(RCVerifiedInvitation RCInvitation {dh = invDh, ts}) <- maybe (throwE RCEInvitation) pure $ verifySignedInvitation signedInv
  unless (invDh == dhPubKey) $ throwE RCEInvitation
+  now <- systemSeconds <$> liftIO getSystemTime
+  unless (now - 3660 <= systemSeconds ts && systemSeconds ts <= now + 3600) $ throwE RCEInvitation
  pure (pairing, inv)
  where
    decrypt :: [RCCtrlPairing] -> Either RCErrorType (RCCtrlPairing, ByteString)
@@ -122,18 +122,22 @@ closeListener subscribers sock =
 joinMulticast :: TMVar Int -> N.Socket -> N.HostAddress -> IO ()
 joinMulticast subscribers sock group = do
  now <- atomically $ takeTMVar subscribers
-  when (now == 0) $ do
-    setMembership sock group True >>= \case
-      Left e -> atomically (putTMVar subscribers now) >> logError ("setMembership failed " <> tshow e)
-      Right () -> atomically $ putTMVar subscribers (now + 1)
+  if now == 0
+    then
+      setMembership sock group True >>= \case
+        Left e -> atomically (putTMVar subscribers now) >> logError ("setMembership failed " <> tshow e)
+        Right () -> atomically $ putTMVar subscribers (now + 1)
+    else atomically $ putTMVar subscribers (now + 1)

 partMulticast :: TMVar Int -> N.Socket -> N.HostAddress -> IO ()
 partMulticast subscribers sock group = do
  now <- atomically $ takeTMVar subscribers
-  when (now == 1) $
-    setMembership sock group False >>= \case
-      Left e -> atomically (putTMVar subscribers now) >> logError ("setMembership failed " <> tshow e)
-      Right () -> atomically $ putTMVar subscribers (now - 1)
+  if now == 1
+    then
+      setMembership sock group False >>= \case
+        Left e -> atomically (putTMVar subscribers (now - 1)) >> logError ("setMembership failed " <> tshow e)
+        Right () -> atomically $ putTMVar subscribers (now - 1)
+    else atomically $ putTMVar subscribers (max 0 (now - 1))

 listenerHostAddr4 :: UDP.ListenSocket -> N.HostAddress
 listenerHostAddr4 sock = case UDP.mySockAddr sock of
@@ -20,6 +20,8 @@ module AgentTests.ConnectionRequestTests

 import AgentTests.EqInstances ()
 import Data.ByteString (ByteString)
+import qualified Data.ByteString.Char8 as B
+import Data.Either (isLeft)
 import Network.HTTP.Types (urlEncode)
 import Simplex.Messaging.Agent.Protocol
 import qualified Simplex.Messaging.Crypto as C
@@ -285,6 +287,9 @@ connectionRequestTests =
      contactAddressV6 #== ("https://simplex.chat/contact#/?v=1-2&smp=" <> url queueStr) -- adjusted to v6
      contactAddressV6 #== ("https://simplex.chat/contact#/?v=2-2&smp=" <> url queueStr)
      contactAddressClientData #==# ("simplex:/contact#/?v=6-8&smp=" <> url queueStr <> "&data=" <> url "{\"type\":\"group_link\", \"group_link_id\":\"abc\"}")
+    it "should reject KEM ciphertext without KEM key in e2e params" $
+      strDecode @(RcvE2ERatchetParamsUri 'C.X448) (strEncode testE2ERatchetParams <> "&kem_ct=" <> strEncode (B.replicate 1039 '\0'))
+        `shouldSatisfy` isLeft
    it "should serialize / parse queue address, connection invitations and contact addresses as binary" $ do
      smpEncodingTest queue
      smpEncodingTest queueNoQM -- this passes, no queue mode patch in SMPQueueUri encoding
@@ -357,6 +362,10 @@ connectionRequestTests =
      smpEncodingTest $ AgentServiceRequest [qInfo] Nothing "service request payload"
      smpEncodingTest $ AgentServiceResponse "service response payload"
      smpEncodingTest $ AgentRejection "rejected: not allowed"
+    it "should serialize and parse ratchet key info" $ do
+      smpDecode "R" `shouldBe` Right (AgentRatchetInfo RatchetInfo {answeredKeyHash = Nothing})
+      smpDecode "R1\3abcdef" `shouldBe` Right (AgentRatchetInfo RatchetInfo {answeredKeyHash = Just "abc"})
+      smpEncodingTest $ AgentRatchetInfo RatchetInfo {answeredKeyHash = Just "0123456789abcdef0123456789abcdef"}
  where
    smpEncodingTest :: (Encoding a, Eq a, Show a, HasCallStack) => a -> Expectation
    smpEncodingTest a = smpDecode (smpEncode a) `shouldBe` Right a
@@ -70,8 +70,8 @@ import Data.ByteString.Char8 (ByteString)
 import qualified Data.ByteString.Char8 as B
 import Data.Either (isRight)
 import Data.Int (Int64)
-import Data.List (find, isPrefixOf, isSuffixOf)
-import Data.List.NonEmpty (NonEmpty)
+import Data.List (find, isInfixOf, isPrefixOf, isSuffixOf)
+import Data.List.NonEmpty (NonEmpty (..))
 import qualified Data.Map as M
 import Data.Maybe (isJust, isNothing)
 import qualified Data.Set as S
@@ -87,12 +87,12 @@ import SMPAgentClient
 import SMPClient
 import Simplex.Messaging.Agent hiding (acceptContact, createConnection, deleteConnection, deleteConnections, getConnShortLink, joinConnection, sendMessage, setConnShortLink, subscribeConnection, suspendConnection)
 import qualified Simplex.Messaging.Agent as A
-import Simplex.Messaging.Agent.Client (ProtocolTestFailure (..), ProtocolTestStep (..), ServerQueueInfo (..), UserNetworkInfo (..), UserNetworkType (..), waitForUserNetwork)
+import Simplex.Messaging.Agent.Client (ProtocolTestFailure (..), ProtocolTestStep (..), ServerQueueInfo (..), UserNetworkInfo (..), UserNetworkType (..), sendAgentMessage, waitForUserNetwork)
 import Simplex.Messaging.Agent.Env.SQLite (AgentConfig (..), Env (..), InitialAgentServers (..), createAgentStore)
 import Simplex.Messaging.Agent.Protocol hiding (CON, CONF, INFO, REQ, SENT)
 import qualified Simplex.Messaging.Agent.Protocol as A
 import Simplex.Messaging.Agent.Store (Connection' (..), SomeConn' (..), StoredRcvQueue (..))
-import Simplex.Messaging.Agent.Store.AgentStore (getConn)
+import Simplex.Messaging.Agent.Store.AgentStore (deleteRatchetKeyHashesExpired, getConn, getConnIds, getRatchetX3dhKeys)
 import Simplex.Messaging.Agent.Store.Common (DBStore (..), withTransaction)
 import Simplex.Messaging.Agent.Store.Interface
 import qualified Simplex.Messaging.Agent.Store.DB as DB
@@ -112,7 +112,7 @@ import Simplex.Messaging.Server.Information (ServerPublicInfo (..))
 import Simplex.Messaging.Server.MsgStore.Types (SMSType (..), SQSType (..))
 import Simplex.Messaging.Server.QueueStore.QueueInfo
 import Simplex.Messaging.Server.StoreLog (StoreLogRecord (..))
-import Simplex.Messaging.Transport (ASrvTransport, SMPVersion, VersionSMP, currentServerSMPRelayVersion, minClientSMPRelayVersion, minServerSMPRelayVersion, alpnSupportedSMPHandshakes, supportedServerSMPRelayVRange)
+import Simplex.Messaging.Transport (ASrvTransport, SMPVersion, VersionSMP, currentServerSMPRelayVersion, minClientSMPRelayVersion, minServerSMPRelayVersion, alpnSupportedSMPHandshakes)
 import Simplex.Messaging.Transport.Server (TransportServerConfig (..))
 import Simplex.Messaging.Util (bshow, diffToMicroseconds)
 import Simplex.Messaging.Version (VersionRange (..))
@@ -231,7 +231,11 @@ pattern Rcvd' :: AgentMsgId -> AgentMsgId -> AEvent 'AEConn
 pattern Rcvd' aMsgId rcvdMsgId <- RCVD MsgMeta {integrity = MsgOk, recipient = (aMsgId, _)} [MsgReceipt {agentMsgId = rcvdMsgId, msgRcptStatus = MROk}]

 smpCfgVPrev :: ProtocolClientConfig SMPVersion
-smpCfgVPrev = (smpCfg agentCfg) {serverVRange = prevRange $ serverVRange $ smpCfg agentCfg}
+smpCfgVPrev =
+  (smpCfg agentCfg)
+    { serverVRange = prevRange $ serverVRange $ smpCfg agentCfg,
+      proxiedRelayVRange = prevRange $ proxiedRelayVRange $ smpCfg agentCfg
+    }

 -- ntfCfgVPrev :: ProtocolClientConfig NTFVersion
 -- ntfCfgVPrev = (ntfCfg agentCfg) {clientALPN = Nothing, serverVRange = V.mkVersionRange (VersionNTF 1) (VersionNTF 1)}
@@ -332,8 +336,6 @@ functionalAPITests ps = do
      withSmpServer ps testServerMultipleIdentities
    it "should connect with two peers" $
      withSmpServer ps testAgentClient3
-    it "should connect with entitlement credential" $
-      withSmpServer ps testAgentEntitlement
    it "should establish connection without PQ encryption and enable it" $
      withSmpServer ps testEnablePQEncryption
  describe "Duplex connection - delivery stress test" $ do
@@ -369,6 +371,10 @@ functionalAPITests ps = do
      testAddDRViaSetConnShortLink ps
    it "should resume DR accept after a transient failure (reuse the send queue and ratchet)" $
      testAcceptContactDRResumeAfterOffline ps
+    it "should store the ratchet when DR accept is prepared" $
+      withSmpServer ps $ testAcceptContactDRPrepared False
+    it "should create the ratchet at DR accept when the prepared connection has none" $
+      withSmpServer ps $ testAcceptContactDRPrepared True
    it "should support rejecting contact request" $
      withSmpServer ps testRejectContactRequest
    it "should communicate rejection reason via double ratchet" $
@@ -413,13 +419,16 @@ functionalAPITests ps = do
    describe "should connect via 1-time short link with async join" $ testProxyMatrix ps testInvitationShortLinkAsync
    describe "should connect via contact short link" $ testProxyMatrix ps testContactShortLink
    describe "should add short link to existing contact and connect" $ testProxyMatrix ps testAddContactShortLink
-    xdescribe "try to create 1-time short link with prev versions" $ testProxyMatrixWithPrev ps testInvitationShortLinkPrev
    describe "server restart" $ do
      it "should get 1-time link data after restart" $ testInvitationShortLinkRestart ps
      it "should connect via contact short link after restart" $ testContactShortLinkRestart ps
      it "should connect via added contact short link after restart" $ testAddContactShortLinkRestart ps
    it "should create and get short links with the old contact queues" $ testOldContactQueueShortLink ps
    it "should connect via prepared connection link" $ testPrepareCreateConnectionLink ps
+    it "should connect via prepared invitation link" $ testPrepareCreateInvitationLink ps
+    it "should not create connection for prepared invitation link with too large data" $ testPrepareInvitationLinkTooLarge ps
+    it "should not create connection for prepared contact link with too large data" $ testPrepareContactLinkTooLarge ps
+    it "should connect via short link prepared for existing contact connection" $ testPrepareConnShortLink ps
  describe "Message delivery" $ do
    describe "update connection agent version on received messages" $ do
      it "should increase if compatible, shouldn'ps decrease" $
@@ -461,6 +470,16 @@ functionalAPITests ps = do
        testRatchetSyncSuspendForeground ps
      it "should synchronize ratchets when clients start synchronization simultaneously" $
        testRatchetSyncSimultaneous ps
+      it "should ignore replayed ratchet key after expired hashes are deleted" $
+        testRatchetSyncReplayedKey ps
+      it "should synchronize ratchets when synchronization is forced again" $
+        testRatchetSyncRepeated ps
+      it "should not mark ratchet key as processed when ratchet recreation fails" $
+        testRatchetSyncFailedKeyNotProcessed ps
+      it "should not store reply ratchet key when ratchet recreation fails" $
+        testRatchetSyncFailedRecreationNoReply ps
+      it "should not store ratchet key when starting synchronization fails" $
+        testRatchetSyncStartFailedNoKey ps
 #endif
    describe "Subscription mode OnlyCreate" $ do
      it "messages delivered only when polled" $
@@ -539,6 +558,10 @@ functionalAPITests ps = do
      testServerMatrix2 ps testFastSwitchConnection
    it "should switch delivery to the new queue when the old server is down" $
      testFastSwitchDeadOldServer ps
+    it "should drain the old queue after QEND on the new queue" $
+      testFastSwitchDrainOldQueue ps
+    it "should drain the old queue after QEND on the new queue and restart" $
+      testFastSwitchDrainOldQueueRestart ps
    describe "should switch delivery to the new queue" $
      testServerMatrix2 ps testSwitchConnection
    describe "should switch to new queue asynchronously" $
@@ -665,19 +688,6 @@ testProxyMatrix ps runTest = do
  it "2 servers, directly" $ withSmpServers2 ps $ withAgentClientsServers2 (agentCfg, initAgentServers) (agentCfg, initAgentServers2) $ runTest False
  it "2 servers, via proxy" $ withSmpServersProxy2 ps $ withAgentClientsServers2 (agentCfg, initAgentServersProxy) (agentCfg, initAgentServersProxy2) $ runTest True

-testProxyMatrixWithPrev :: HasCallStack => (ASrvTransport, AStoreType) -> (Bool -> Bool -> AgentClient -> AgentClient -> IO ()) -> Spec
-testProxyMatrixWithPrev ps@(t, msType@(ASType qs _ms)) runTest = do
-  it "2 servers, directly, curr clients, prev servers" $ withSmpServers2Prev $ withAgentClientsServers2 (agentCfg, initAgentServers) (agentCfg, initAgentServers2) $ runTest False True
-  it "2 servers, via proxy, curr clients, prev servers" $ withSmpServersProxy2Prev $ withAgentClientsServers2 (agentCfg, initAgentServersProxy) (agentCfg, initAgentServersProxy2) $ runTest True True
-  it "2 servers, directly, prev clients, curr servers" $ withSmpServers2 ps $ withAgentClientsServers2 (agentCfgVPrevPQ, initAgentServers) (agentCfgVPrevPQ, initAgentServers2) $ runTest False False
-  it "2 servers, via proxy, prev clients, curr servers" $ withSmpServersProxy2 ps $ withAgentClientsServers2 (agentCfgVPrevPQ, initAgentServersProxy) (agentCfgVPrevPQ, initAgentServersProxy2) $ runTest True False
-  where
-    prev cfg' = updateCfg cfg' $ \cfg_ -> cfg_ {smpServerVRange = prevRange supportedServerSMPRelayVRange}
-    withSmpServers2Prev a = withServers2 (prev $ cfgMS msType) (prev $ cfgJ2QS qs) a
-    withSmpServersProxy2Prev a = withServers2 (prev $ proxyCfgMS msType) (prev $ proxyCfgJ2QS qs) a
-    withServers2 cfg1 cfg2 a =
-      withSmpServerConfigOn t cfg1 testPort $ \_ -> withSmpServerConfigOn t cfg2 testPort2 $ \_ -> a
-
 testPQMatrix2 :: HasCallStack => (ASrvTransport, AStoreType) -> (HasCallStack => (AgentClient, InitialKeys) -> (AgentClient, PQSupport) -> AgentMsgId -> IO ()) -> Spec
 testPQMatrix2 = pqMatrix2_ True

@@ -981,15 +991,6 @@ testAgentClient3 =
    get c =##> \case ("", connId, Msg "c5") -> connId == aIdForC; _ -> False
    ackMessage c aIdForC 3 Nothing

-testAgentEntitlement :: HasCallStack => IO ()
-testAgentEntitlement = do
-  (keys, credential) <- mkTestEntitlement
-  let aCfg = agentCfg {entitlementKeys = keys}
-      servers = initAgentServers {entitlements = M.fromList [(1, credential)]}
-  withAgentClientsCfgServers2 aCfg aCfg servers $ \a b -> runRight_ $ do
-    (aId, bId) <- makeConnection a b
-    exchangeGreetings a bId b aId
-
 runAgentClientContactTest :: HasCallStack => PQSupport -> SndQueueSecured -> Bool -> AgentClient -> AgentClient -> AgentMsgId -> IO ()
 runAgentClientContactTest pqSupport sqSecured viaProxy alice bob baseId =
  runAgentClientContactTestPQ sqSecured viaProxy (alice, IKLinkPQ pqSupport) (bob, pqSupport) baseId
@@ -1248,6 +1249,30 @@ testAcceptContactDRResumeAfterOffline ps = withAgentClients2 $ \alice bob -> do
    ("", _, A.CONF confId _ _ "alice's connInfo") <- get bob
    allowConfirmGreet alice bobId bob aliceId confId addrIK pqEnc

+testAcceptContactDRPrepared :: HasCallStack => Bool -> IO ()
+testAcceptContactDRPrepared ratchetDeleted =
+  withAgentClients2 $ \alice bob -> runRight_ $ do
+    let userLinkData = UserContactLinkData UserContactData {direct = True, owners = [], relays = [], userData = UserLinkData "test user data", ratchetKeys = Nothing}
+        pqEnc = PQEncryption $ pqConnectionMode IKPQOn PQSupportOn
+    (_, CCLink connReq _) <- A.createConnection alice NRMInteractive 1 True True SCMContact (Just userLinkData) Nothing IKPQOn True SMSubscribe
+    (aliceId, CRBRatchet codes) <- A.prepareConnectionToJoin bob 1 True connReq PQSupportOn
+    void $ A.joinConnection bob NRMInteractive 1 aliceId True connReq "bob's connInfo" PQSupportOn SMSubscribe
+    ("", _, A.REQ invId _ _ "bob's connInfo" (CRBRatchet reqCodes) _) <- get alice
+    (bobId, CRBRatchet acceptCodes) <- A.prepareConnectionToAccept alice 1 True invId PQSupportOn
+    liftIO $ do
+      reqCodes `shouldBe` codes
+      acceptCodes `shouldBe` codes
+    if ratchetDeleted
+      then do
+        liftIO $ withTransaction (store $ agentEnv alice) (`DB.execute_` "DELETE FROM ratchets")
+        Left (CONN NOT_FOUND _) <- tryError $ getConnectionVerifyCodes alice bobId
+        pure ()
+      else getConnectionVerifyCodes alice bobId >>= liftIO . (`shouldBe` codes)
+    void $ acceptContact alice 1 bobId True invId "alice's connInfo" PQSupportOn SMSubscribe
+    ("", _, A.CONF confId _ _ "alice's connInfo") <- get bob
+    allowConfirmGreet alice bobId bob aliceId confId IKPQOn pqEnc
+    getConnectionVerifyCodes alice bobId >>= liftIO . (`shouldBe` codes)
+
 runAgentClientContactTestPQ3 :: HasCallStack => Bool -> (AgentClient, InitialKeys) -> (AgentClient, PQSupport) -> (AgentClient, PQSupport) -> AgentMsgId -> IO ()
 runAgentClientContactTestPQ3 viaProxy (alice, aPQ) (bob, bPQ) (tom, tPQ) baseId = runRight_ $ do
  (_, CCLink qInfo Nothing) <- A.createConnection alice NRMInteractive 1 True True SCMContact Nothing Nothing aPQ False SMSubscribe
@@ -1788,14 +1813,6 @@ testJoinConn_ viaProxy sndSecure a bId b connReq = do
  get b ##> ("", aId, CON)
  exchangeGreetingsViaProxy viaProxy a bId b aId

-testInvitationShortLinkPrev :: HasCallStack => Bool -> Bool -> AgentClient -> AgentClient -> IO ()
-testInvitationShortLinkPrev viaProxy sndSecure a b = runRight_ $ do
-  let userData = UserLinkData "some user data"
-      newLinkData = UserInvLinkData userData
-  -- can't create short link with previous version
-  (bId, CCLink connReq Nothing) <- A.createConnection a NRMInteractive 1 True True SCMInvitation (Just newLinkData) Nothing CR.IKPQOn False SMSubscribe
-  testJoinConn_ viaProxy sndSecure a bId b connReq
-
 testInvitationShortLinkAsync :: HasCallStack => Bool -> AgentClient -> AgentClient -> IO ()
 testInvitationShortLinkAsync viaProxy a b = do
  let userData = UserLinkData "some user data"
@@ -2070,6 +2087,64 @@ testPrepareCreateConnectionLink ps = withSmpServer ps $ withAgentClients2 $ \a b
    get b ##> ("", bId, CON)
    exchangeGreetings a aId b bId

+testPrepareCreateInvitationLink :: HasCallStack => (ASrvTransport, AStoreType) -> IO ()
+testPrepareCreateInvitationLink ps = withSmpServer ps $ withAgentClients2 $ \a b -> do
+  let userData = UserLinkData "test user data"
+  runRight_ $ do
+    (preparedReq, preparedParams@PreparedLinkParams {plpLinkKey}) <- A.prepareInvitationLink a 1 CR.IKPQOn Nothing
+    (bId, CCLink connReq (Just shortLink@(CSLInvitation _ _ _ linkKey))) <- A.createInvitationForLink a NRMInteractive 1 True preparedReq preparedParams (UserInvLinkData userData) SMSubscribe
+    liftIO $ linkKey `shouldBe` plpLinkKey
+    (_, connData', connReq') <- getConnShortLink b 1 shortLink
+    liftIO $ connReq' `shouldBe` preparedReq
+    liftIO $ connReq `shouldNotBe` preparedReq
+    liftIO $ linkUserData connData' `shouldBe` userData
+    testJoinConn_ False True a bId b connReq
+
+testPrepareInvitationLinkTooLarge :: HasCallStack => (ASrvTransport, AStoreType) -> IO ()
+testPrepareInvitationLinkTooLarge ps = withSmpServer ps $ withAgent 1 agentCfg initAgentServers testDB $ \a -> do
+  runRight_ $ do
+    (preparedReq, preparedParams) <- A.prepareInvitationLink a 1 CR.IKPQOn Nothing
+    Left (A.CMD LARGE _) <- tryError $ A.createInvitationForLink a NRMInteractive 1 True preparedReq preparedParams (UserInvLinkData $ UserLinkData $ B.replicate 14000 'a') SMSubscribe
+    pure ()
+  withTransaction (store $ agentEnv a) getConnIds `shouldReturn` []
+
+testPrepareContactLinkTooLarge :: HasCallStack => (ASrvTransport, AStoreType) -> IO ()
+testPrepareContactLinkTooLarge ps = withSmpServer ps $ withAgent 1 agentCfg initAgentServers testDB $ \a -> do
+  let userCtData = UserContactData {direct = True, owners = [], relays = [], userData = UserLinkData $ B.replicate 14000 'a', ratchetKeys = Nothing}
+  g <- C.newRandom
+  rootKey <- atomically $ C.generateKeyPair g
+  linkEntId <- atomically $ C.randomBytes 32 g
+  runRight_ $ do
+    (ccLink, preparedParams) <- A.prepareConnectionLink a 1 rootKey linkEntId True Nothing CR.IKPQOn True Nothing
+    Left (A.CMD LARGE _) <- tryError $ A.createConnectionForLink a NRMInteractive 1 True ccLink preparedParams (UserContactLinkData userCtData) SMSubscribe
+    pure ()
+  withTransaction (store $ agentEnv a) getConnIds `shouldReturn` []
+
+testPrepareConnShortLink :: HasCallStack => (ASrvTransport, AStoreType) -> IO ()
+testPrepareConnShortLink ps = withSmpServer ps $ withAgentClients2 $ \a b -> do
+  let userCtData = UserContactData {direct = True, owners = [], relays = [], userData = UserLinkData "test user data", ratchetKeys = Nothing}
+  runRight_ $ do
+    (contactId, CCLink _ Nothing) <- A.createConnection a NRMInteractive 1 True True SCMContact Nothing Nothing CR.IKPQOn False SMSubscribe
+    shortLink <- A.prepareConnShortLink a contactId Nothing
+    shortLink' <- A.prepareConnShortLink a contactId Nothing
+    liftIO $ shortLink' `shouldBe` shortLink
+    shortLink'' <- A.setConnShortLink a NRMInteractive contactId SCMContact (UserContactLinkData userCtData) Nothing False Nothing
+    liftIO $ shortLink'' `shouldBe` shortLink
+    (_, ContactLinkData _ userCtData', connReq) <- getConnShortLink b 1 shortLink
+    liftIO $ userCtData' `shouldBe` userCtData
+    (aId, sndSecure) <- joinConnection b 1 True connReq "bob's connInfo" SMSubscribe
+    liftIO $ sndSecure `shouldBe` False
+    ("", _, REQ invId _ "bob's connInfo") <- get a
+    (bId, _) <- A.prepareConnectionToAccept a 1 True invId PQSupportOn
+    sndSecure' <- acceptContact a 1 bId True invId "alice's connInfo" PQSupportOn SMSubscribe
+    liftIO $ sndSecure' `shouldBe` True
+    ("", _, CONF confId _ "alice's connInfo") <- get b
+    allowConnection b aId confId "bob's connInfo"
+    get a ##> ("", bId, INFO "bob's connInfo")
+    get a ##> ("", bId, CON)
+    get b ##> ("", aId, CON)
+    exchangeGreetings a bId b aId
+
 connReqWithKeys :: BinaryConnectionRequestUri m -> Maybe AddressRatchetKeys -> ConnectionRequestUri m
 connReqWithKeys cr rk = case cr of
  BCRInvitationUri crData e2eParams -> CRInvitationUri crData e2eParams
@@ -2755,6 +2830,117 @@ testRatchetSyncSimultaneous ps = do
  disposeAgentClient bob
  disposeAgentClient bob2

+testRatchetSyncReplayedKey :: HasCallStack => (ASrvTransport, AStoreType) -> IO ()
+testRatchetSyncReplayedKey ps = withAgentClients2 $ \alice bob -> do
+  (aliceId, bobId, bob2) <- withSmpServerStoreMsgLogOn ps testPort $ \_ ->
+    setupDesynchronizedRatchet alice bob
+  ("", "", DOWN _ _) <- nGet alice
+  ("", "", DOWN _ _) <- nGet bob2
+  _ <- runRight $ synchronizeRatchet bob2 aliceId PQSupportOn False
+  Right pks <- withTransaction (store $ agentEnv bob2) (`getRatchetX3dhKeys` aliceId)
+  Right (SomeConn _ (DuplexConnection _ _ (sq :| _))) <- withTransaction (store $ agentEnv bob2) (`getConn` aliceId)
+  withSmpServerStoreMsgLogOn ps testPort $ \_ -> do
+    concurrently_
+      (getInAnyOrder alice [ratchetSyncP' bobId RSAgreed, serverUpP])
+      (getInAnyOrder bob2 [ratchetSyncP' aliceId RSAgreed, serverUpP])
+    get alice =##> ratchetSyncP bobId RSOk
+    get bob2 =##> ratchetSyncP aliceId RSOk
+    withTransaction (store $ agentEnv alice) $ \db -> deleteRatchetKeyHashesExpired db 0 100
+    let keyMsg = AgentRatchetKey {agentVersion = currentSMPAgentVersion, e2eEncryption = CR.mkRcvE2ERatchetParams CR.currentE2EEncryptVersion pks, info = ""}
+    Right _ <- runReaderT (runExceptT $ sendAgentMessage bob2 sq SMP.noMsgFlags $ smpEncode keyMsg) (agentEnv bob2)
+    runRight_ $ exchangeGreetingsMsgIds alice bobId 10 bob2 aliceId 7
+  disposeAgentClient bob2
+
+testRatchetSyncRepeated :: HasCallStack => (ASrvTransport, AStoreType) -> IO ()
+testRatchetSyncRepeated ps = withAgentClients2 $ \alice bob -> do
+  (aliceId, bobId, bob2) <- startRatchetSyncOffline ps alice bob
+  ConnectionStats {ratchetSyncState = rss2} <- runRight $ synchronizeRatchet bob2 aliceId PQSupportOn True
+  rss2 `shouldBe` RSStarted
+
+  withSmpServerStoreMsgLogOn ps testPort $ \_ -> do
+    concurrently_
+      (getInAnyOrder alice [ratchetSyncP' bobId RSAgreed, serverUpP])
+      (getInAnyOrder bob2 [ratchetSyncP' aliceId RSAgreed, serverUpP])
+    runRight_ $ do
+      get alice =##> ratchetSyncP bobId RSAgreed
+      get alice =##> ratchetSyncP bobId RSOk
+      get bob2 =##> ratchetSyncP aliceId RSOk
+      msgId <- sendMessage alice bobId SMP.noMsgFlags "hello"
+      get alice ##> ("", bobId, SENT msgId)
+      get bob2 =##> \case ("", c, Msg "hello") -> c == aliceId; _ -> False
+      ackMessage bob2 aliceId 8 Nothing
+  map fst <$> processedRatchetKeyHashes bob2 `shouldReturn` [aliceId, aliceId]
+  disposeAgentClient bob2
+
+testRatchetSyncFailedKeyNotProcessed :: HasCallStack => (ASrvTransport, AStoreType) -> IO ()
+testRatchetSyncFailedKeyNotProcessed ps = withAgentClients2 $ \alice bob -> do
+  (aliceId, bobId, bob2) <- startRatchetSyncOffline ps alice bob
+  withTransaction (store $ agentEnv bob2) $ \db ->
+    DB.execute_ db "UPDATE ratchets SET x3dh_priv_key_1 = NULL"
+
+  withSmpServerStoreMsgLogOn ps testPort $ \_ ->
+    concurrently_
+      (getInAnyOrder alice [ratchetSyncP' bobId RSAgreed, serverUpP])
+      (getInAnyOrder bob2 [x3dhKeysNotFoundP aliceId, serverUpP])
+  map fst <$> processedRatchetKeyHashes alice `shouldReturn` [bobId]
+  processedRatchetKeyHashes bob2 `shouldReturn` []
+  disposeAgentClient bob2
+  where
+    x3dhKeysNotFoundP :: ConnId -> ATransmission -> Bool
+    x3dhKeysNotFoundP cId = \case
+      (_, cId', AEvt SAEConn (ERR (A.INTERNAL e))) -> cId' == cId && "SEX3dhKeysNotFound" `isPrefixOf` e
+      _ -> False
+
+testRatchetSyncFailedRecreationNoReply :: HasCallStack => (ASrvTransport, AStoreType) -> IO ()
+testRatchetSyncFailedRecreationNoReply ps = withAgentClients2 $ \alice bob -> do
+  (_, bobId, bob2) <- startRatchetSyncOffline ps alice bob
+  aliceSndMsgs <- sndMessages alice
+  withTransaction (store $ agentEnv alice) $ \db ->
+    DB.execute_ db "CREATE TRIGGER fail_ratchet_insert BEFORE INSERT ON ratchets BEGIN SELECT RAISE(ABORT, 'ratchet insert failed'); END"
+  withSmpServerStoreMsgLogOn ps testPort $ \_ ->
+    concurrently_
+      (getInAnyOrder alice [ratchetInsertFailedP bobId, serverUpP])
+      (getInAnyOrder bob2 [serverUpP])
+  processedRatchetKeyHashes alice `shouldReturn` []
+  sndMessages alice `shouldReturn` aliceSndMsgs
+  disposeAgentClient bob2
+  where
+    ratchetInsertFailedP :: ConnId -> ATransmission -> Bool
+    ratchetInsertFailedP cId = \case
+      (_, cId', AEvt SAEConn (ERR (A.INTERNAL e))) -> cId' == cId && "ratchet insert failed" `isInfixOf` e
+      _ -> False
+
+testRatchetSyncStartFailedNoKey :: HasCallStack => (ASrvTransport, AStoreType) -> IO ()
+testRatchetSyncStartFailedNoKey ps = withAgentClients2 $ \alice bob -> do
+  (aliceId, _, bob2) <- withSmpServerStoreMsgLogOn ps testPort $ \_ ->
+    setupDesynchronizedRatchet alice bob
+  bobSndMsgs <- sndMessages bob2
+  withTransaction (store $ agentEnv bob2) $ \db ->
+    DB.execute_ db "CREATE TRIGGER fail_ratchet_update BEFORE UPDATE ON ratchets BEGIN SELECT RAISE(ABORT, 'ratchet update failed'); END"
+  Left (A.INTERNAL e) <- runExceptT $ synchronizeRatchet bob2 aliceId PQSupportOff False
+  e `shouldContain` "ratchet update failed"
+  ConnectionStats {ratchetSyncState} <- runRight $ getConnectionServers bob2 aliceId
+  ratchetSyncState `shouldBe` RSRequired
+  withTransaction (store $ agentEnv bob2) (`DB.query_` "SELECT conn_id, pq_support FROM connections") `shouldReturn` [(aliceId, PQSupportOn)]
+  sndMessages bob2 `shouldReturn` bobSndMsgs
+  disposeAgentClient bob2
+
+startRatchetSyncOffline :: HasCallStack => (ASrvTransport, AStoreType) -> AgentClient -> AgentClient -> IO (ConnId, ConnId, AgentClient)
+startRatchetSyncOffline ps alice bob = do
+  (aliceId, bobId, bob2) <- withSmpServerStoreMsgLogOn ps testPort $ \_ ->
+    setupDesynchronizedRatchet alice bob
+  ("", "", DOWN _ _) <- nGet alice
+  ("", "", DOWN _ _) <- nGet bob2
+  ConnectionStats {ratchetSyncState} <- runRight $ synchronizeRatchet bob2 aliceId PQSupportOn False
+  ratchetSyncState `shouldBe` RSStarted
+  pure (aliceId, bobId, bob2)
+
+processedRatchetKeyHashes :: AgentClient -> IO [(ConnId, ByteString)]
+processedRatchetKeyHashes c = withTransaction (store $ agentEnv c) (`DB.query_` "SELECT conn_id, hash FROM processed_ratchet_key_hashes")
+
+sndMessages :: AgentClient -> IO [(ConnId, Int64)]
+sndMessages c = withTransaction (store $ agentEnv c) (`DB.query_` "SELECT conn_id, internal_id FROM snd_messages ORDER BY conn_id, internal_id")
+
 getMsg :: AgentClient -> ConnId -> ExceptT AgentErrorType IO a -> ExceptT AgentErrorType IO a
 getMsg c cId action = do
  liftIO $ noMessages c "nothing should be delivered before GET"
@@ -3637,7 +3823,7 @@ testFastSwitchDeadOldServer :: HasCallStack => (ASrvTransport, AStoreType) -> IO
 testFastSwitchDeadOldServer ps@(t, ASType qsType _) = do
  let bServers = initAgentServers {smp = userServers [testSMPServer2]}
  withSmpServerConfigOn t (cfgJ2QS qsType) testPort2 $ \_ ->
-    withAgent 1 agentCfg initAgentServers testDB $ \a ->
+    withAgent 1 aCfg initAgentServers testDB $ \a ->
      withAgent 2 agentCfg bServers testDB2 $ \b -> do
        (aId, bId) <- withSmpServerStoreLogOn ps testPort $ \_ -> runRight $ do
          (aId, bId) <- makeConnection a b
@@ -3653,7 +3839,10 @@ testFastSwitchDeadOldServer ps@(t, ASType qsType _) = do
          queuedReceived <- drainSwitchCompletedRcvMsg a bId "queued while down"
          liftIO $ queuedReceived `shouldBe` True
          drainSwitchCompleted b aId QDSnd
+          waitOneRcvQueue a bId
          exchangeGreetingsMsgId 7 a bId b aId
+  where
+    aCfg = agentCfg {initialCleanupDelay = 10000, cleanupInterval = 10000, deleteErrorCount = 3}

 -- drains switch and network events until the connection reports SPCompleted in the given direction,
 -- tolerating DOWN/UP and intermediate phases (the old server is stopped mid-rotation)
@@ -3673,6 +3862,69 @@ drainSwitchCompletedRcvMsg c connId body = go False
        (_, connId', AEvt SAEConn (Msg' mId _ body')) | connId' == connId && body' == body -> ackMessage c connId' mId Nothing >> go True
        _ -> go seen

+testFastSwitchDrainOldQueue :: HasCallStack => (ASrvTransport, AStoreType) -> IO ()
+testFastSwitchDrainOldQueue ps =
+  withSmpServers2 ps $ withAgentClients2 $ \a b -> runRight_ $ do
+    (aId, bId, aM1Id) <- endSwitchOnNewQueue a b
+    ackMessage a bId aM1Id Nothing
+    drainOldQueue a bId b aId
+
+testFastSwitchDrainOldQueueRestart :: HasCallStack => (ASrvTransport, AStoreType) -> IO ()
+testFastSwitchDrainOldQueueRestart ps =
+  withSmpServers2 ps $
+    withAgent 2 agentCfg initAgentServers testDB2 $ \b -> do
+      (aId, bId, _) <- withAgent 1 agentCfg initAgentServers testDB $ \a -> runRight $ endSwitchOnNewQueue a b
+      withAgent 1 agentCfg initAgentServers testDB $ \a -> runRight_ $ do
+        subscribeConnection a bId
+        drainOldQueue a bId b aId
+
+endSwitchOnNewQueue :: HasCallStack => AgentClient -> AgentClient -> ExceptT AgentErrorType IO (ConnId, ConnId, AgentMsgId)
+endSwitchOnNewQueue a b = do
+  (aId, bId) <- makeConnection a b
+  exchangeGreetings a bId b aId
+  liftIO $ setProtocolServers a 1 [noAuthSrvCfg testSMPServer2]
+  m1Id <- sendMessage b aId SMP.noMsgFlags "m1"
+  get b ##> ("", aId, SENT m1Id)
+  ("", c, Msg' aM1Id _ "m1") <- get a
+  liftIO $ c `shouldBe` bId
+  m2Id <- sendMessage b aId SMP.noMsgFlags "m2"
+  get b ##> ("", aId, SENT m2Id)
+  _ <- switchConnectionAsync a "" bId
+  fastSwitchComplete a bId b aId
+  stats <- getConnectionServers a bId
+  liftIO $ rcvSwchStatuses' stats `shouldMatchList` [Nothing, Just RSReceivedQEND]
+  pure (aId, bId, aM1Id)
+
+drainOldQueue :: HasCallStack => AgentClient -> ConnId -> AgentClient -> ConnId -> ExceptT AgentErrorType IO ()
+drainOldQueue a bId b aId = do
+  ("", c, MSG MsgMeta {recipient = (aM2Id, _)} _ "m2") <- get a
+  liftIO $ c `shouldBe` bId
+  ackMessage a bId aM2Id Nothing
+  waitOneRcvQueue a bId
+  bMsgId <- sendMessage b aId SMP.noMsgFlags "hello"
+  get b ##> ("", aId, SENT bMsgId)
+  ("", c', MSG MsgMeta {recipient = (aMsgId, _)} _ "hello") <- get a
+  liftIO $ c' `shouldBe` bId
+  ackMessage a bId aMsgId Nothing
+  aMsgId' <- sendMessage a bId SMP.noMsgFlags "hello too"
+  get a ##> ("", bId, SENT aMsgId')
+  ("", c'', MSG MsgMeta {recipient = (bMsgId', _)} _ "hello too") <- get b
+  liftIO $ c'' `shouldBe` aId
+  ackMessage b aId bMsgId' Nothing
+  liftIO $ noMessages a "nothing else should be delivered to alice"
+  liftIO $ noMessages b "nothing else should be delivered to bob"
+
+waitOneRcvQueue :: HasCallStack => AgentClient -> ConnId -> ExceptT AgentErrorType IO ()
+waitOneRcvQueue c connId = go (300 :: Int)
+  where
+    go n = do
+      stats <- getConnectionServers c connId
+      case rcvSwchStatuses' stats of
+        [Nothing] -> pure ()
+        statuses
+          | n > 0 -> liftIO (threadDelay 100000) >> go (n - 1)
+          | otherwise -> liftIO $ expectationFailure $ "old receive queue was not deleted: " <> show statuses
+
 phaseRcv :: AgentClient -> ByteString -> SwitchPhase -> [Maybe RcvSwitchStatus] -> ExceptT AgentErrorType IO ()
 phaseRcv c connId p swchStatuses = phase c connId QDRcv p (\stats -> rcvSwchStatuses' stats `shouldMatchList` swchStatuses)

@@ -4769,7 +5021,7 @@ testServerQueueInfo = do
    Just srvMsgId <- checkMsgQ bob aliceId 1
    get bob =##> \case
      ("", c, MSG MsgMeta {integrity = MsgOk, broker = (smId, _), recipient = (mId, _), pqEncryption = PQEncOn} _ "hello") ->
-        c == aliceId && decodeLatin1 (B64.encode smId) == srvMsgId && mId == msgId
+        c == aliceId && decodeLatin1 (B64.encode $ SMP.unMsgId smId) == srvMsgId && mId == msgId
      _ -> False
    ackMessage bob aliceId msgId Nothing
    liftIO $ threadDelay 200000
@@ -4800,9 +5052,9 @@ testServerQueueInfo = do
    get bob =##> \case ("", c, Msg' mId PQEncOn "hello 4") -> c == aliceId && mId == msgId4; _ -> False
    ackMessage bob aliceId msgId4 Nothing
    liftIO $ threadDelay 200000
-    Just _ <- checkMsgQ bob aliceId 1 -- the one that did not fit now accepted
    get alice ##> ("", bobId, QCONT)
    get alice ##> ("", bobId, SENT msgId5)
+    Just _ <- checkMsgQ bob aliceId 1 -- the one that did not fit now accepted
    liftIO $ threadDelay 200000
    Just _srvMsgId <- checkQ bob aliceId True (Just QNoSub) 1 (Just MTMessage)
    get bob =##> \case ("", c, Msg' mId PQEncOn "hello: quota exceeded") -> c == aliceId && mId == msgId5 + 1; _ -> False
@@ -230,7 +230,7 @@ testNotificationToken apns = do
    APNSMockRequest {notification = APNSNotification {aps = APNSBackground _, notificationData = Just ntfData}} <-
      getMockNotification apns tkn
    verification <- ntfData .-> "verification"
-    nonce <- C.cbNonce <$> ntfData .-> "nonce"
+    nonce <- C.unsafeCbNonce <$> ntfData .-> "nonce"
    verifyNtfToken a tkn nonce verification
    NTActive <- checkNtfToken a tkn
    deleteNtfToken a tkn
@@ -254,7 +254,7 @@ testNtfTokenRepeatRegistration apns = do
    APNSMockRequest {notification = APNSNotification {aps = APNSBackground _, notificationData = Just ntfData}} <-
      getMockNotification apns tkn
    verification <- ntfData .-> "verification"
-    nonce <- C.cbNonce <$> ntfData .-> "nonce"
+    nonce <- C.unsafeCbNonce <$> ntfData .-> "nonce"
    NTRegistered <- registerNtfToken a tkn NMPeriodic
    APNSMockRequest {notification = APNSNotification {aps = APNSBackground _, notificationData = Just ntfData'}} <-
      getMockNotification apns tkn
@@ -273,14 +273,14 @@ testNtfTokenSecondRegistration apns =
    APNSMockRequest {notification = APNSNotification {aps = APNSBackground _, notificationData = Just ntfData}} <-
      getMockNotification apns tkn
    verification <- ntfData .-> "verification"
-    nonce <- C.cbNonce <$> ntfData .-> "nonce"
+    nonce <- C.unsafeCbNonce <$> ntfData .-> "nonce"
    verifyNtfToken a tkn nonce verification

    NTRegistered <- registerNtfToken a' tkn NMPeriodic
    APNSMockRequest {notification = APNSNotification {aps = APNSBackground _, notificationData = Just ntfData'}} <-
      getMockNotification apns tkn
    verification' <- ntfData' .-> "verification"
-    nonce' <- C.cbNonce <$> ntfData' .-> "nonce"
+    nonce' <- C.unsafeCbNonce <$> ntfData' .-> "nonce"

    -- at this point the first token is still active
    NTActive <- checkNtfToken a tkn
@@ -311,7 +311,7 @@ testNtfTokenServerRestart t apns = do
    -- so that repeat verification happens without restarting the clients, when notification arrives
    withNtfServer t $ runRight_ $ do
      verification <- ntfData .-> "verification"
-      nonce <- C.cbNonce <$> ntfData .-> "nonce"
+      nonce <- C.unsafeCbNonce <$> ntfData .-> "nonce"
      verifyNtfToken a' tkn nonce verification
      NTActive <- checkNtfToken a' tkn
      pure ()
@@ -327,7 +327,7 @@ testNtfTokenServerRestartReverify t apns = do
      pure ntfData
    runRight_ $ do
      verification <- ntfData .-> "verification"
-      nonce <- C.cbNonce <$> ntfData .-> "nonce"
+      nonce <- C.unsafeCbNonce <$> ntfData .-> "nonce"
      Left (BROKER _ (NETWORK _)) <- tryE $ verifyNtfToken a tkn nonce verification
      pure ()
  threadDelay 1500000
@@ -348,7 +348,7 @@ testNtfTokenServerRestartReverifyTimeout t apns = do
      APNSMockRequest {notification = APNSNotification {aps = APNSBackground _, notificationData = Just ntfData}} <-
        getMockNotification apns tkn
      verification <- ntfData .-> "verification"
-      nonce <- C.cbNonce <$> ntfData .-> "nonce"
+      nonce <- C.unsafeCbNonce <$> ntfData .-> "nonce"
      verifyNtfToken a tkn nonce verification
      pure (nonce, verification)
    -- this emulates the situation when server verified token but the client did not receive the response
@@ -393,7 +393,7 @@ testNtfTokenServerRestartReregister t apns = do
      APNSMockRequest {notification = APNSNotification {aps = APNSBackground _, notificationData = Just ntfData}} <-
        getMockNotification apns tkn
      verification <- ntfData .-> "verification"
-      nonce <- C.cbNonce <$> ntfData .-> "nonce"
+      nonce <- C.unsafeCbNonce <$> ntfData .-> "nonce"
      verifyNtfToken a' tkn nonce verification
      NTActive <- checkNtfToken a' tkn
      pure ()
@@ -428,7 +428,7 @@ testNtfTokenServerRestartReregisterTimeout t apns = do
      APNSMockRequest {notification = APNSNotification {aps = APNSBackground _, notificationData = Just ntfData}} <-
        getMockNotification apns tkn
      verification <- ntfData .-> "verification"
-      nonce <- C.cbNonce <$> ntfData .-> "nonce"
+      nonce <- C.unsafeCbNonce <$> ntfData .-> "nonce"
      verifyNtfToken a' tkn nonce verification
      NTActive <- checkNtfToken a' tkn
      pure ()
@@ -450,7 +450,7 @@ testNtfTokenMultipleServers t apns = do
        APNSMockRequest {notification = APNSNotification {aps = APNSBackground _, notificationData = Just ntfData}} <-
          getMockNotification apns tkn
        verification <- ntfData .-> "verification"
-        nonce <- C.cbNonce <$> ntfData .-> "nonce"
+        nonce <- C.unsafeCbNonce <$> ntfData .-> "nonce"
        verifyNtfToken a tkn nonce verification
        NTActive <- checkNtfToken a tkn
        -- shut down the "other" server
@@ -566,7 +566,7 @@ testNotificationSubscriptionExistingConnection apns baseId alice@AgentClient {ag
    APNSMockRequest {notification = APNSNotification {aps = APNSBackground _, notificationData = Just ntfData}} <-
      getMockNotification apns tkn
    verification <- ntfData .-> "verification"
-    vNonce <- C.cbNonce <$> ntfData .-> "nonce"
+    vNonce <- C.unsafeCbNonce <$> ntfData .-> "nonce"
    verifyNtfToken alice tkn vNonce verification
    NTActive <- checkNtfToken alice tkn
    -- send message
@@ -657,7 +657,7 @@ registerTestToken a token mode apns = do
  Just APNSMockRequest {notification = APNSNotification {aps = APNSBackground _, notificationData = Just ntfData'}} <-
    timeout 1000000 $ getMockNotification apns tkn
  verification' <- ntfData' .-> "verification"
-  nonce' <- C.cbNonce <$> ntfData' .-> "nonce"
+  nonce' <- C.unsafeCbNonce <$> ntfData' .-> "nonce"
  verifyNtfToken a tkn nonce' verification'
  NTActive <- checkNtfToken a tkn
  pure tkn
@@ -1035,7 +1035,7 @@ messageNotification apns tkn = do
  500000 `timeout` getMockNotification apns tkn >>= \case
    Nothing -> error "no notification"
    Just APNSMockRequest {notification = APNSNotification {aps = APNSMutableContent {}, notificationData = Just ntfData}} -> do
-      nonce <- C.cbNonce <$> ntfData .-> "nonce"
+      nonce <- C.unsafeCbNonce <$> ntfData .-> "nonce"
      message <- ntfData .-> "message"
      pure (nonce, message)
    _ -> error "bad notification"
@@ -20,12 +20,13 @@ import Control.Concurrent.Async (concurrently_)
 import Control.Concurrent.MVar
 import Control.Concurrent.STM
 import Control.Exception (SomeException)
-import Control.Monad (replicateM_)
+import Control.Monad (forM_, replicateM_)
 import Control.Monad.Trans.Except
 import Crypto.Random (ChaChaDRG)
 import Data.ByteArray (ScrubbedBytes)
 import Data.ByteString.Char8 (ByteString)
 import Data.List (isInfixOf)
+import qualified Data.Map.Strict as M
 import qualified Data.Text as T
 import Data.Text.Encoding (encodeUtf8)
 import Data.Time
@@ -51,6 +52,7 @@ import qualified Simplex.Messaging.Crypto as C
 import Simplex.Messaging.Crypto.File (CryptoFile (..))
 import Simplex.Messaging.Crypto.Ratchet (pattern IKPQOn)
 import qualified Simplex.Messaging.Crypto.Ratchet as CR
+import Simplex.Messaging.Encoding (Encoding (..))
 import Simplex.Messaging.Encoding.String (StrEncoding (..))
 import Simplex.Messaging.Protocol (EntityId (..), QueueMode (..), SubscriptionMode (..), pattern VersionSMPC)
 import qualified Simplex.Messaging.Protocol as SMP
@@ -135,6 +137,8 @@ storeTests = do
          testCreateRcvMsg
          testCreateSndMsg
          testCreateRcvAndSndMsgs
+      describe "deleteRatchetKeyHashesExpired" testDeleteRatchetKeyHashesExpired
+      it "should keep only the newest skipped message keys" testGetSkippedMsgKeys
      describe "Work items" $ do
        it "should getPendingQueueMsg" testGetPendingQueueMsg
        it "should getPendingServerCommand" testGetPendingServerCommand
@@ -509,7 +513,7 @@ hw = encodeUtf8 "Hello world!"
 ts :: UTCTime
 ts = UTCTime (fromGregorian 2021 02 24) (secondsToDiffTime 0)

-mkRcvMsgData :: InternalId -> InternalRcvId -> ExternalSndId -> BrokerId -> MsgHash -> RcvMsgData
+mkRcvMsgData :: InternalId -> InternalRcvId -> ExternalSndId -> ByteString -> MsgHash -> RcvMsgData
 mkRcvMsgData internalId internalRcvId externalSndId brokerId internalHash =
  RcvMsgData
    { internalRcvId,
@@ -518,7 +522,7 @@ mkRcvMsgData internalId internalRcvId externalSndId brokerId internalHash =
          { integrity = MsgOk,
            recipient = (unId internalId, ts),
            sndMsgId = externalSndId,
-            broker = (brokerId, ts),
+            broker = (SMP.unsafeMsgId $ mconcat (replicate 24 brokerId), ts),
            pqEncryption = CR.PQEncOn
          },
      msgType = AM_A_MSG_,
@@ -599,6 +603,42 @@ testCreateRcvAndSndMsgs =
      testCreateSndMsg_ db "snd_hash_1" connId sq $ mkSndMsgData (InternalId 5) (InternalSndId 2) "snd_hash_2"
      testCreateSndMsg_ db "snd_hash_2" connId sq $ mkSndMsgData (InternalId 6) (InternalSndId 3) "snd_hash_3"

+testDeleteRatchetKeyHashesExpired :: SpecWith DBStore
+testDeleteRatchetKeyHashesExpired =
+  it "should delete expired ratchet key hashes except the newest in each connection" . withStoreTransaction $ \db -> do
+    g <- C.newRandom
+    Right connId <- createNewConn db g cData1 {connId = ""} SCMInvitation
+    Right connId' <- createNewConn db g cData1 {connId = ""} SCMContact
+    let hashes = ["h1", "h2", "h3", "h4", "h5", "h6"]
+    forM_ hashes $ addProcessedRatchetKeyHash db connId
+    forM_ (take 4 hashes) $ addProcessedRatchetKeyHash db connId'
+    deleteRatchetKeyHashesExpired db 86400 4
+    mapM (checkRatchetKeyHashExists db connId) hashes `shouldReturn` replicate 6 True
+    deleteRatchetKeyHashesExpired db 0 4
+    mapM (checkRatchetKeyHashExists db connId) hashes `shouldReturn` [False, False, True, True, True, True]
+    mapM (checkRatchetKeyHashExists db connId') (take 4 hashes) `shouldReturn` replicate 4 True
+
+testGetSkippedMsgKeys :: DBStore -> Expectation
+testGetSkippedMsgKeys st = do
+  g <- C.newRandom
+  withTransaction st $ \db -> do
+    Right connId <- createNewConn db g cData1 {connId = ""} SCMInvitation
+    Right connId' <- createNewConn db g cData1 {connId = ""} SCMInvitation
+    createSkippedKeys db connId'
+    createSkippedKeys db connId
+    M.map M.keys <$> getSkippedMsgKeys db connId 4
+      `shouldReturn` M.singleton (C.Key "header_key") [1, 2, 3, 4]
+    getMsgNs db connId `shouldReturn` [1 .. 4]
+    getMsgNs db connId' `shouldReturn` [1 .. 10]
+  where
+    createSkippedKeys :: DB.Connection -> ConnId -> IO ()
+    createSkippedKeys db connId = do
+      DB.execute db "INSERT INTO ratchets (conn_id) VALUES (?)" (Only connId)
+      forM_ ([10, 9 .. 1] :: [Int]) $ \msgN ->
+        DB.execute db "INSERT INTO skipped_messages (conn_id, header_key, msg_n, msg_key) VALUES (?, ?, ?, ?)" (connId, "header_key" :: ByteString, msgN, smpEncode ("key" :: ByteString, "iv" :: ByteString))
+    getMsgNs :: DB.Connection -> ConnId -> IO [Int]
+    getMsgNs db connId = map fromOnly <$> DB.query db "SELECT msg_n FROM skipped_messages WHERE conn_id = ? ORDER BY msg_n" (Only connId)
+
 testCloseReopenStore :: IO ()
 testCloseReopenStore = do
  st <- createStore'
@@ -648,7 +688,7 @@ hasMigrations :: DBStore -> Expectation
 hasMigrations st = getMigrations st `shouldReturn` True

 errorGettingMigrations :: DBStore -> Expectation
-errorGettingMigrations st = getMigrations st `shouldThrow` \(e :: SomeException) -> "ErrorMisuse" `isInfixOf` show e
+errorGettingMigrations st = getMigrations st `shouldThrow` \(e :: SomeException) -> "withTransaction: database closed" `isInfixOf` show e

 testGetPendingQueueMsg :: DBStore -> Expectation
 testGetPendingQueueMsg st = do
@@ -48,6 +48,8 @@ schemaDumpTest = do
  it "verify strict tables" testVerifyStrict
  it "should NOT create user record for new database" testUsersMigrationNew
  it "should create user record for old database" testUsersMigrationOld
+  it "should remove duplicate ratchet key hashes before adding unique index" testRatchetKeyHashesUniqueMigration
+  it "should clear received_qend switch status on downgrade" testRcvSwitchStatusDowngrade

 testVerifySchemaDump :: IO ()
 testVerifySchemaDump = do
@@ -114,12 +116,45 @@ testUsersMigrationOld = do
    `shouldReturn` ([Only (1 :: Int)])
  closeDBStore st'

+testRatchetKeyHashesUniqueMigration :: IO ()
+testRatchetKeyHashesUniqueMigration = do
+  let beforeUnique = takeWhile (("m20260929_ratchet_indexes" /=) . name) appMigrations
+  Right st <- createDBStore (DBOpts testDB [] "" False True TQOff) beforeUnique (MigrationConfig MCError Nothing)
+  withTransaction' st $ \db -> do
+    SQL.execute_ db "INSERT INTO users (user_id) VALUES (1)"
+    SQL.execute_ db "INSERT INTO connections (conn_id, conn_mode, user_id) VALUES (x'01', 'INV', 1), (x'02', 'INV', 1)"
+    SQL.execute_ db "INSERT INTO processed_ratchet_key_hashes (conn_id, hash) VALUES (x'01', x'aa'), (x'01', x'aa'), (x'01', x'bb'), (x'02', x'aa'), (x'01', x'aa')"
+  closeDBStore st
+  Right st' <- createDBStore (DBOpts testDB [] "" False True TQOff) appMigrations (MigrationConfig MCYesUp Nothing)
+  withTransaction' st' (`SQL.query_` "SELECT processed_ratchet_key_hash_id FROM processed_ratchet_key_hashes ORDER BY processed_ratchet_key_hash_id")
+    `shouldReturn` [Only (1 :: Int), Only 3, Only 4]
+  closeDBStore st'
+
+testRcvSwitchStatusDowngrade :: IO ()
+testRcvSwitchStatusDowngrade = do
+  Right st <- createDBStore (DBOpts testDB [] "" False True TQOff) appMigrations (MigrationConfig MCError Nothing)
+  withTransaction' st $ \db -> do
+    SQL.execute_ db "INSERT INTO users (user_id) VALUES (1)"
+    SQL.execute_ db "INSERT INTO connections (conn_id, conn_mode, user_id) VALUES (x'01', 'INV', 1)"
+    SQL.execute_ db "INSERT INTO servers (host, port, key_hash) VALUES ('localhost', '5001', x'00')"
+    SQL.execute_ db "INSERT INTO rcv_queues (host, port, rcv_id, conn_id, rcv_private_key, rcv_dh_secret, e2e_priv_key, snd_id, status, rcv_queue_id, rcv_primary, switch_status) VALUES ('localhost', '5001', x'01', x'01', x'00', x'00', x'00', x'01', 'active', 1, 0, 'received_qend'), ('localhost', '5001', x'02', x'01', x'00', x'00', x'00', x'02', 'active', 2, 1, 'sending_qadd')"
+  closeDBStore st
+  let beforeRcvSwitchStatus = takeWhile (("m20261008_rcv_switch_status" /=) . name) appMigrations
+  Right st' <- createDBStore (DBOpts testDB [] "" False True TQOff) beforeRcvSwitchStatus (MigrationConfig MCYesUpDown Nothing)
+  withTransaction' st' (`SQL.query_` "SELECT switch_status FROM rcv_queues ORDER BY rcv_queue_id")
+    `shouldReturn` [Only (Nothing :: Maybe Text), Only (Just "sending_qadd")]
+  closeDBStore st'
+
 skipComparisonForDownMigrations :: [String]
 skipComparisonForDownMigrations =
  [ -- on down migration idx_messages_internal_snd_id_ts index moves down to the end of the file
    "m20230814_indexes",
    -- snd_secure and last_broker_ts columns swap order on down migration
-    "m20250322_short_links"
+    "m20250322_short_links",
+    -- on down migration idx_processed_ratchet_key_hashes_hash index moves down to the end of the file
+    "m20260929_ratchet_indexes",
+    -- sqlite_sequence moves after commands table after VACUUM
+    "m20261005_commands_autoincrement"
  ]

 getSchema :: FilePath -> FilePath -> IO String
@@ -108,8 +108,6 @@ smpServerTest storeLog basicAuth = do
  lookupValue "TRANSPORT" "websockets" ini `shouldBe` Right "off"
  lookupValue "AUTH" "new_queues" ini `shouldBe` Right "on"
  lookupValue "INACTIVE_CLIENTS" "disconnect" ini `shouldBe` Right "on"
-  lookupValue "ADDRESS_STATS" "enable" ini `shouldBe` Right "off"
-  lookupValue "ADDRESS_STATS" "period" ini `shouldBe` Right "300"
  doesFileExist (cfgPath <> "/ca.key") `shouldReturn` True
  -- start
  r <- lines <$> capture_ (withArgs ["start"] $ (100000 `timeout` smpServerCLI cfgPath logPath) `catchAll_` pure (Just ()))
@@ -195,7 +193,7 @@ smpServerTestStatic = do
        X.Certificate {X.certPubKey = X.PubKeyEd25519 _k} : _ca -> print _ca -- pure ()
        leaf : _ -> error $ "Unexpected leaf cert: " <> show leaf
        [] -> error "Empty chain"
-      runRight_ . void $ smpClientHandshake tls Nothing caSMP supportedClientSMPRelayVRange False Nothing (\_ -> pure Nothing)
+      runRight_ . void $ smpClientHandshake tls Nothing caSMP supportedClientSMPRelayVRange False Nothing
    logDebug "Combined SMP works"
  where
    getCerts :: TLS 'TClient -> [X.Certificate]
@@ -236,8 +234,6 @@ ntfServerTest storeLog = do
  lookupValue "STORE_LOG" "log_stats" ini `shouldBe` Right "off"
  lookupValue "TRANSPORT" "port" ini `shouldBe` Right "443"
  lookupValue "TRANSPORT" "websockets" ini `shouldBe` Right "off"
-  lookupValue "ADDRESS_STATS" "enable" ini `shouldBe` Right "off"
-  lookupValue "ADDRESS_STATS" "period" ini `shouldBe` Right "300"
  doesFileExist (ntfCfgPath <> "/ca.key") `shouldReturn` True
  r <- lines <$> capture_ (withArgs ["start"] $ (100000 `timeout` ntfServerCLI ntfCfgPath ntfLogPath) `catchAll_` pure (Just ()))
  r `shouldContain` ["SMP notifications server v" <> simplexmqVersionCommit]
@@ -256,8 +252,6 @@ xftpServerTest storeLog = do
  lookupValue "STORE_LOG" "enable" ini `shouldBe` Right (if storeLog then "on" else "off")
  lookupValue "STORE_LOG" "log_stats" ini `shouldBe` Right "off"
  lookupValue "TRANSPORT" "port" ini `shouldBe` Right "443"
-  lookupValue "ADDRESS_STATS" "enable" ini `shouldBe` Right "off"
-  lookupValue "ADDRESS_STATS" "period" ini `shouldBe` Right "300"
  doesFileExist (fileCfgPath <> "/ca.key") `shouldReturn` True
  r <- lines <$> capture_ (withArgs ["start"] $ (100000 `timeout` xftpServerCLI fileCfgPath fileLogPath) `catchAll_` pure (Just ()))
  r `shouldContain` ["SimpleX XFTP server v" <> simplexmqVersionCommit]
@@ -1,326 +0,0 @@
-{-# LANGUAGE CPP #-}
-{-# LANGUAGE LambdaCase #-}
-{-# LANGUAGE NamedFieldPuns #-}
-{-# LANGUAGE OverloadedStrings #-}
-{-# LANGUAGE ScopedTypeVariables #-}
-
-module CoreTests.AddressStatsTests where
-
-import Data.ByteString.Char8 (ByteString)
-import qualified Data.ByteString.Char8 as B
-import Data.IORef (readIORef)
-import Data.List.NonEmpty (NonEmpty (..))
-import qualified Data.Map.Strict as M
-import qualified Data.Set as S
-import Data.Text (Text)
-import qualified Data.Text as T
-import Data.Text.Encoding (decodeLatin1)
-import Network.Socket (SockAddr (..), tupleToHostAddress, tupleToHostAddress6)
-import qualified Simplex.FileTransfer.Protocol as XFTP
-import Simplex.FileTransfer.Server.Env (XFTPAddrCounter (..), xftpCmdCounter)
-import Simplex.FileTransfer.Transport (supportedFileServerVRange)
-import qualified Simplex.Messaging.Crypto as C
-import Simplex.Messaging.Protocol
-import Simplex.Messaging.Server.AddressStats
-import Simplex.Messaging.Server.Env.STM (SMPAddrCounter (..), smpCmdCounter)
-import Simplex.Messaging.SimplexName (SimplexDomain (..), SimplexTLD (..))
-import Simplex.Messaging.Transport (supportedClientSMPRelayVRange, supportedServerSMPRelayVRange)
-import Simplex.Messaging.Version (VersionRange (..))
-import Test.Hspec hiding (fit, it)
-import UnliftIO.STM
-import Util
-#if defined(dbServerPostgres)
-import qualified Simplex.Messaging.Notifications.Protocol as NTF
-import Simplex.Messaging.Notifications.Server.Env (NtfAddrCounter (..), ntfCmdCounter)
-import Simplex.Messaging.Notifications.Transport (supportedServerNTFVRange)
-#endif
-
-data TestCounter = TCConnections | TCSend | TCGet
-  deriving (Eq, Ord, Enum, Bounded, Show)
-
-instance AddrCounter TestCounter where
-  counterName = \case
-    TCConnections -> "connections"
-    TCSend -> "SEND"
-    TCGet -> "GET"
-  counterBounds _ = [1, 2, 5, 10]
-  connectionsCounter = TCConnections
-
-addr1, addr2, addr3, addr4 :: AddrKey
-addr1 = AKIPv4 1
-addr2 = AKIPv4 2
-addr3 = AKIPv4 3
-addr4 = AKIPv4 4
-
-addressStatsTests :: Spec
-addressStatsTests = do
-  describe "addrKey" addrKeyTests
-  describe "bounds" boundsTests
-  describe "counterByName" counterByNameTests
-  describe "openAddrStats" openAddrStatsTests
-  describe "rolloverAddrStats" rolloverTests
-  describe "topAddresses" topAddressesTests
-  describe "addrHistogramMetrics" metricsTests
-  describe "command counters" commandCounterTests
-
-addrKeyTests :: Spec
-addrKeyTests = do
-  it "should use IPv4 address" $
-    addrKeyText <$> addrKey (ipv4 (192, 168, 1, 2)) `shouldBe` Just "192.168.1.2"
-  it "should use IPv4 address of IPv4-mapped IPv6 address" $
-    addrKey (ipv6 (0, 0, 0, 0, 0, 0xffff, 0xc0a8, 0x0102)) `shouldBe` addrKey (ipv4 (192, 168, 1, 2))
-  it "should use one key for IPv6 addresses in one /64" $ do
-    addrKey (ipv6 (0x2001, 0xdb8, 1, 2, 3, 4, 5, 6)) `shouldBe` addrKey (ipv6 (0x2001, 0xdb8, 1, 2, 7, 8, 9, 10))
-    addrKeyText <$> addrKey (ipv6 (0x2001, 0xdb8, 1, 2, 3, 4, 5, 6)) `shouldBe` Just "2001:db8:1:2::/64"
-  it "should use different keys for IPv6 addresses in different /64" $
-    addrKey (ipv6 (0x2001, 0xdb8, 1, 2, 3, 4, 5, 6)) `shouldNotBe` addrKey (ipv6 (0x2001, 0xdb8, 1, 3, 3, 4, 5, 6))
-  it "should not use other address types" $
-    addrKey (SockAddrUnix "tests/tmp/socket") `shouldBe` Nothing
-  where
-    ipv4 a = SockAddrInet 443 $ tupleToHostAddress a
-    ipv6 a = SockAddrInet6 443 0 (tupleToHostAddress6 a) 0
-
-boundsTests :: Spec
-boundsTests = do
-  it "should use R10 values up to 1000000 for counts" $
-    countBounds
-      `shouldBe` [ 1, 2, 3, 4, 5, 6, 7, 8, 9,
-                   10, 13, 16, 20, 25, 32, 40, 50, 63, 80,
-                   100, 125, 160, 200, 250, 315, 400, 500, 630, 800,
-                   1000, 1250, 1600, 2000, 2500, 3150, 4000, 5000, 6300, 8000,
-                   10000, 12500, 16000, 20000, 25000, 31500, 40000, 50000, 63000, 80000,
-                   100000, 125000, 160000, 200000, 250000, 315000, 400000, 500000, 630000, 800000,
-                   1000000
-                 ]
-  it "should use R10 values up to 100000000 for kilobytes" $ do
-    take 60 kilobyteBounds `shouldBe` countBounds
-    drop 59 kilobyteBounds
-      `shouldBe` [ 1000000, 1250000, 1600000, 2000000, 2500000, 3150000, 4000000, 5000000, 6300000, 8000000,
-                   10000000, 12500000, 16000000, 20000000, 25000000, 31500000, 40000000, 50000000, 63000000, 80000000,
-                   100000000
-                 ]
-
-counterByNameTests :: Spec
-counterByNameTests = do
-  it "should find SMP counters" $ testCounterNames [minBound .. maxBound :: SMPAddrCounter]
-  it "should find XFTP counters" $ testCounterNames [minBound .. maxBound :: XFTPAddrCounter]
-#if defined(dbServerPostgres)
-  it "should find NTF counters" $ testCounterNames [minBound .. maxBound :: NtfAddrCounter]
-#endif
-  it "should not find unknown counter" $
-    counterByName "unknown" `shouldBe` (Nothing :: Maybe SMPAddrCounter)
-  where
-    testCounterNames :: (AddrCounter c, Show c) => [c] -> Expectation
-    testCounterNames cs = map (counterByName . counterName) cs `shouldBe` map Just cs
-
-openAddrStatsTests :: Spec
-openAddrStatsTests =
-  it "should count connections of one address in one entry" $ do
-    ServerAddrStats {addrStatsMap = m} <- newServerAddrStats
-    s <- openAddrStats m addr1
-    s' <- openAddrStats m addr1
-    readTVarIO (connectionsCount s) `shouldReturn` 2
-    counts s TCConnections `shouldReturn` (0, 2)
-    closeAddrStats s'
-    readTVarIO (connectionsCount s) `shouldReturn` 1
-
-rolloverTests :: Spec
-rolloverTests = do
-  it "should add non-zero closing counts to histograms" $ do
-    stats@ServerAddrStats {addrStatsMap = m, addrHistograms} <- newServerAddrStats
-    s1 <- openAddrStats m addr1
-    s2 <- openAddrStats m addr2
-    addAddrCounter s1 TCSend 3
-    addAddrCounter s2 TCSend 7
-    rolloverAddrStats stats
-    readIORef addrHistograms
-      `shouldReturn` M.fromList
-        [ (TCConnections, AddrHistogram [2, 2, 2, 2] 2 2 1),
-          (TCSend, AddrHistogram [0, 0, 1, 2] 10 2 7),
-          (TCGet, AddrHistogram [0, 0, 0, 0] 0 0 0)
-        ]
-    addAddrCounter s1 TCSend 20
-    rolloverAddrStats stats
-    readIORef addrHistograms
-      `shouldReturn` M.fromList
-        [ (TCConnections, AddrHistogram [2, 2, 2, 2] 2 2 0),
-          (TCSend, AddrHistogram [0, 0, 1, 2] 30 3 20),
-          (TCGet, AddrHistogram [0, 0, 0, 0] 0 0 0)
-        ]
-  it "should set previous counts to closing counts" $ do
-    stats@ServerAddrStats {addrStatsMap = m} <- newServerAddrStats
-    s <- openAddrStats m addr1
-    addAddrCounter s TCSend 3
-    counts s TCSend `shouldReturn` (0, 3)
-    rolloverAddrStats stats
-    counts s TCSend `shouldReturn` (3, 0)
-    addAddrCounter s TCSend 5
-    rolloverAddrStats stats
-    counts s TCSend `shouldReturn` (5, 0)
-    rolloverAddrStats stats
-    counts s TCSend `shouldReturn` (0, 0)
-  it "should keep entries with open connections or closing counts, and delete other entries" $ do
-    stats@ServerAddrStats {addrStatsMap = m} <- newServerAddrStats
-    _ <- openAddrStats m addr1
-    s2 <- openAddrStats m addr2
-    s3 <- openAddrStats m addr3
-    closeAddrStats s3
-    rolloverAddrStats stats
-    M.keys <$> readTVarIO m `shouldReturn` [addr1, addr2, addr3]
-    addAddrCounter s2 TCSend 1
-    closeAddrStats s2
-    rolloverAddrStats stats
-    M.keys <$> readTVarIO m `shouldReturn` [addr1, addr2]
-    rolloverAddrStats stats
-    M.keys <$> readTVarIO m `shouldReturn` [addr1]
-
-topAddressesTests :: Spec
-topAddressesTests =
-  it "should return addresses with non-zero counts, sorted by the sum of previous and current counts" $ do
-    stats@ServerAddrStats {addrStatsMap = m} <- newServerAddrStats
-    [s1, s2, s3, _] <- mapM (openAddrStats m) [addr1, addr2, addr3, addr4]
-    addAddrCounter s1 TCSend 3
-    addAddrCounter s2 TCSend 7
-    rolloverAddrStats stats
-    addAddrCounter s1 TCSend 5
-    addAddrCounter s3 TCSend 10
-    topAddresses m TCSend 10 `shouldReturn` [(addr3, 0, 10), (addr1, 3, 5), (addr2, 7, 0)]
-    topAddresses m TCSend 2 `shouldReturn` [(addr3, 0, 10), (addr1, 3, 5)]
-
-metricsTests :: Spec
-metricsTests =
-  it "should encode histograms and maximums as Prometheus metrics" $
-    addrHistogramMetrics "simplex_test" "1767225600000" histograms
-      `shouldBe` T.unlines
-        [ "# Client addresses",
-          "# ----------------",
-          "",
-          "# HELP simplex_test_client_address_period_count Counts of client addresses per period",
-          "# TYPE simplex_test_client_address_period_count histogram",
-          "simplex_test_client_address_period_count_bucket{counter=\"SEND\",le=\"1\"} 0 1767225600000",
-          "simplex_test_client_address_period_count_bucket{counter=\"SEND\",le=\"2\"} 0 1767225600000",
-          "simplex_test_client_address_period_count_bucket{counter=\"SEND\",le=\"5\"} 1 1767225600000",
-          "simplex_test_client_address_period_count_bucket{counter=\"SEND\",le=\"10\"} 2 1767225600000",
-          "simplex_test_client_address_period_count_bucket{counter=\"SEND\",le=\"+Inf\"} 2 1767225600000",
-          "simplex_test_client_address_period_count_sum{counter=\"SEND\"} 10 1767225600000",
-          "simplex_test_client_address_period_count_count{counter=\"SEND\"} 2 1767225600000",
-          "simplex_test_client_address_period_count_bucket{counter=\"GET\",le=\"1\"} 0 1767225600000",
-          "simplex_test_client_address_period_count_bucket{counter=\"GET\",le=\"2\"} 0 1767225600000",
-          "simplex_test_client_address_period_count_bucket{counter=\"GET\",le=\"5\"} 0 1767225600000",
-          "simplex_test_client_address_period_count_bucket{counter=\"GET\",le=\"10\"} 0 1767225600000",
-          "simplex_test_client_address_period_count_bucket{counter=\"GET\",le=\"+Inf\"} 1 1767225600000",
-          "simplex_test_client_address_period_count_sum{counter=\"GET\"} 12 1767225600000",
-          "simplex_test_client_address_period_count_count{counter=\"GET\"} 1 1767225600000",
-          "",
-          "# HELP simplex_test_client_address_period_max Maximum count of a client address in the last period",
-          "# TYPE simplex_test_client_address_period_max gauge",
-          "simplex_test_client_address_period_max{counter=\"SEND\"} 7 1767225600000",
-          "simplex_test_client_address_period_max{counter=\"GET\"} 12 1767225600000",
-          ""
-        ]
-  where
-    histograms =
-      M.fromList
-        [ (TCSend, AddrHistogram [0, 0, 1, 2] 10 2 7),
-          (TCGet, AddrHistogram [0, 0, 0, 0] 12 1 12)
-        ]
-
-commandCounterTests :: Spec
-commandCounterTests = do
-  it "should count each SMP command in the counter named by its tag" $ do
-    cmds <- smpCommands
-    map (counterName . smpCmdCounter) cmds `shouldBe` map (commandTag . encodeProtocol (maxVersion supportedServerSMPRelayVRange)) cmds
-    S.fromList (map smpCmdCounter cmds) `shouldBe` S.fromList [SACNew .. SACRslv]
-  it "should count each XFTP command in the counter named by its tag" $ do
-    cmds <- xftpCommands
-    map (counterName . xftpCmdCounter) cmds `shouldBe` map (commandTag . encodeProtocol (maxVersion supportedFileServerVRange)) cmds
-    S.fromList (map xftpCmdCounter cmds) `shouldBe` S.fromList [XACFNew .. XACPing]
-#if defined(dbServerPostgres)
-  it "should count each NTF command in the counter named by its tag" $ do
-    cmds <- ntfCommands
-    map (counterName . ntfCmdCounter) cmds `shouldBe` map (commandTag . encodeProtocol (maxVersion supportedServerNTFVRange)) cmds
-    S.fromList (map ntfCmdCounter cmds) `shouldBe` S.fromList [NACTNew .. NACPing]
-#endif
-  where
-    commandTag :: ByteString -> Text
-    commandTag = decodeLatin1 . B.takeWhile (/= ' ')
-
-counts :: AddrStats TestCounter -> TestCounter -> IO (Int, Int)
-counts AddrStats {previous, current} c = (,) <$> readIORef (previous M.! c) <*> readIORef (current M.! c)
-
-testKeys :: IO (C.APublicAuthKey, C.APrivateAuthKey, C.PublicKeyX25519)
-testKeys = do
-  g <- C.newRandom
-  (authKey, authPrivKey) <- atomically $ C.generateAuthKeyPair C.SEd25519 g
-  (dhKey, _ :: C.PrivateKeyX25519) <- atomically $ C.generateKeyPair g
-  pure (authKey, authPrivKey, dhKey)
-
-testSMPServer :: SMPServer
-testSMPServer = SMPServer "localhost" "5001" (C.KeyHash "hash")
-
-smpCommands :: IO [Cmd]
-smpCommands = do
-  (authKey, _, dhKey) <- testKeys
-  let newQueue = NewQueueReq {rcvAuthKey = authKey, rcvDhKey = dhKey, auth_ = Nothing, subMode = SMSubscribe, queueReqData = Nothing, ntfCreds = Nothing}
-      linkData = (EncDataBytes "fixed", EncDataBytes "user")
-      name = NQDomain SimplexDomain {nameTLD = TLDSimplex, domain = "alice", subDomain = []}
-  pure
-    [ Cmd SCreator $ NEW newQueue,
-      Cmd SRecipient SUB,
-      Cmd SRecipientService $ SUBS 1 mempty,
-      Cmd SRecipient $ KEY authKey,
-      Cmd SRecipient $ RKEY (authKey :| []),
-      Cmd SRecipient $ LSET (EntityId "link") linkData,
-      Cmd SRecipient LDEL,
-      Cmd SRecipient $ NKEY authKey dhKey,
-      Cmd SRecipient NDEL,
-      Cmd SRecipient GET,
-      Cmd SRecipient $ ACK "message",
-      Cmd SRecipient OFF,
-      Cmd SRecipient DEL,
-      Cmd SRecipient QUE,
-      Cmd SSender $ SKEY authKey,
-      Cmd SSender $ SEND noMsgFlags "hello",
-      Cmd SIdleClient PING,
-      Cmd SSenderLink $ LKEY authKey,
-      Cmd SSenderLink LGET,
-      Cmd SNotifier NSUB,
-      Cmd SNotifierService $ NSUBS 1 mempty,
-      Cmd SProxiedClient $ PRXY testSMPServer Nothing,
-      Cmd SProxiedClient $ PFWD (maxVersion supportedClientSMPRelayVRange) dhKey (EncTransmission "transmission"),
-      Cmd SProxyService $ RFWD (EncFwdTransmission "transmission"),
-      Cmd SResolver $ RSLV name
-    ]
-
-xftpCommands :: IO [XFTP.FileCmd]
-xftpCommands = do
-  (authKey, _, dhKey) <- testKeys
-  pure
-    [ XFTP.FileCmd XFTP.SFSender $ XFTP.FNEW (XFTP.FileInfo authKey 65536 "digest") (authKey :| []) Nothing Nothing,
-      XFTP.FileCmd XFTP.SFSender $ XFTP.FADD (authKey :| []),
-      XFTP.FileCmd XFTP.SFSender XFTP.FPUT,
-      XFTP.FileCmd XFTP.SFSender XFTP.FDEL,
-      XFTP.FileCmd XFTP.SFRecipient $ XFTP.FGET dhKey,
-      XFTP.FileCmd XFTP.SFRecipient XFTP.FACK,
-      XFTP.FileCmd XFTP.SFRecipient XFTP.PING
-    ]
-
-#if defined(dbServerPostgres)
-ntfCommands :: IO [NTF.NtfCmd]
-ntfCommands = do
-  (authKey, authPrivKey, dhKey) <- testKeys
-  let token = NTF.DeviceToken NTF.PPApnsTest "token"
-      queue = NTF.SMPQueueNtf testSMPServer (EntityId "notifier")
-  pure
-    [ NTF.NtfCmd NTF.SToken $ NTF.TNEW $ NTF.NewNtfTkn token authKey dhKey,
-      NTF.NtfCmd NTF.SToken $ NTF.TVFY $ NTF.NtfRegCode "code",
-      NTF.NtfCmd NTF.SToken NTF.TCHK,
-      NTF.NtfCmd NTF.SToken $ NTF.TRPL token,
-      NTF.NtfCmd NTF.SToken NTF.TDEL,
-      NTF.NtfCmd NTF.SToken $ NTF.TCRN 20,
-      NTF.NtfCmd NTF.SSubscription $ NTF.SNEW $ NTF.NewNtfSub (EntityId "token") queue authPrivKey,
-      NTF.NtfCmd NTF.SSubscription NTF.SCHK,
-      NTF.NtfCmd NTF.SSubscription NTF.SDEL,
-      NTF.NtfCmd NTF.SSubscription NTF.PING
-    ]
-#endif
@@ -14,11 +14,13 @@ import Control.Monad
 import Crypto.Random (ChaChaDRG)
 import qualified Data.ByteString as B
 import Data.ByteString.Char8 (ByteString)
+import Data.ByteString.Unsafe (unsafeUseAsCString)
 import qualified Data.List.NonEmpty as L
 import Data.Time.Clock.System (SystemTime, getSystemTime)
 import qualified Data.X509 as X
 import qualified Data.X509.CertificateStore as XS
 import qualified Data.X509.File as XF
+import Foreign.Ptr (plusPtr)
 import Simplex.Messaging.Client
 import qualified Simplex.Messaging.Crypto as C
 import Simplex.Messaging.Encoding
@@ -40,6 +42,8 @@ batchingTests = do
    it "should batch subscription responses with message" testBatchSubResponses
    it "should break on message that does not fit" testClientBatchWithMessage
    it "should break on large message" testClientBatchWithLargeMessage
+  describe "tDecodeServer" $
+    it "should copy IDs out of received block" testDecodeServerCopiesIds

 testBatchSubscriptions :: IO ()
 testBatchSubscriptions = do
@@ -166,6 +170,26 @@ testClientBatchWithLargeMessage = do
  (length rs1', length rs2') `shouldBe` (75, 135)
  all lenOk [s1', s2'] `shouldBe` True

+testDecodeServerCopiesIds :: IO ()
+testDecodeServerCopiesIds = do
+  sessId <- atomically . C.randomBytes 32 =<< C.newRandom
+  subs <- replicateM 2 $ randomSUB sessId
+  let thParams = testTHandleParams sessId
+  [TBTransmissions s 2 _] <- pure $ batchTransmissions thParams $ L.fromList subs
+  forM_ (tParse thParams s) $ \t -> do
+    let (corrId, entId, _) = tDecodeClient @SMPVersion @ErrorType @Cmd thParams t
+    Right (_, _, (corrId', entId', _)) <- pure $ tDecodeServer @SMPVersion @ErrorType @Cmd (testTHandleParams sessId) t
+    (corrId', entId') `shouldBe` (corrId, entId)
+    sharesBuffer s (bs corrId) `shouldReturn` True
+    sharesBuffer s (unEntityId entId) `shouldReturn` True
+    sharesBuffer s (bs corrId') `shouldReturn` False
+    sharesBuffer s (unEntityId entId') `shouldReturn` False
+
+sharesBuffer :: ByteString -> ByteString -> IO Bool
+sharesBuffer block s =
+  unsafeUseAsCString block $ \blockPtr -> unsafeUseAsCString s $ \ptr ->
+    pure $ ptr >= blockPtr && ptr < blockPtr `plusPtr` B.length block
+
 testClientStub :: IO (ProtocolClient SMPVersion ErrorType BrokerMsg)
 testClientStub = do
  g <- C.newRandom
@@ -183,7 +207,7 @@ randomSUB sessId = do
  thAuth_ <- testTHandleAuth g rKey
  let thParams = testTHandleParams sessId
      TransmissionForAuth {tForAuth, tToSend} = encodeTransmissionForAuth thParams (CorrId corrId, EntityId rId, Cmd SRecipient SUB)
-  pure $ (,tToSend) <$> authTransmission thAuth_ True (Just rpKey) nonce tForAuth
+  pure $ (,tToSend) <$> authTransmission thAuth_ True (Just rpKey) (Just nonce) tForAuth

 randomSUBCmd :: ProtocolClient SMPVersion ErrorType BrokerMsg -> IO (PCTransmission ErrorType BrokerMsg)
 randomSUBCmd c = do
@@ -202,7 +226,7 @@ randomNMSGCmd :: SystemTime -> IO (Transmission BrokerMsg)
 randomNMSGCmd ts = do
  g <- C.newRandom
  nId <- atomically $ C.randomBytes 24 g
-  msgId <- atomically $ C.randomBytes 24 g
+  msgId <- atomically $ randomMsgId 24 g
  (k, pk) <- atomically $ C.generateKeyPair g
  nonce <- atomically $ C.randomCbNonce g
  let msgMeta = NMsgMeta {msgId, msgTs = ts}
@@ -221,7 +245,7 @@ randomMSG = do
  g <- C.newRandom
  corrId <- atomically $ C.randomBytes 24 g
  rId <- atomically $ C.randomBytes 24 g
-  msgId <- atomically $ C.randomBytes 24 g
+  msgId <- atomically $ randomMsgId 24 g
  msg <- atomically $ C.randomBytes maxMessageLength g
  pure (CorrId corrId, EntityId rId, MSG RcvMessage {msgId, msgBody = EncRcvMsgBody msg})

@@ -235,9 +259,9 @@ randomSEND sessId len = do
  msg <- atomically $ C.randomBytes len g
  let thParams = testTHandleParams sessId
      TransmissionForAuth {tForAuth, tToSend} = encodeTransmissionForAuth thParams (CorrId corrId, EntityId sId, Cmd SSender $ SEND noMsgFlags msg)
-  pure $ (,tToSend) <$> authTransmission thAuth_ False (Just spKey) nonce tForAuth
+  pure $ (,tToSend) <$> authTransmission thAuth_ False (Just spKey) (Just nonce) tForAuth

-testTHandleParams :: ByteString -> THandleParams SMPVersion 'TClient
+testTHandleParams :: ByteString -> THandleParams SMPVersion p
 testTHandleParams sessionId =
  THandleParams
    { sessionId,
@@ -6,8 +6,9 @@

 module CoreTests.CryptoTests (cryptoTests) where

+import Control.Concurrent (forkIO, newEmptyMVar, putMVar, takeMVar)
 import Control.Concurrent.STM
-import Control.Exception (evaluate)
+import Control.Exception (bracket, evaluate)
 import Control.Monad.Except
 import qualified Data.Aeson as J
 import qualified Data.ByteString.Char8 as B
@@ -22,9 +23,12 @@ import Data.Time.Clock (UTCTime (..))
 import qualified Data.Text.Lazy as LT
 import qualified Data.Text.Lazy.Encoding as LE
 import Data.Type.Equality
+import Data.Word (Word8)
 import qualified Data.X509 as X
 import qualified Data.X509.CertificateStore as XS
 import qualified Data.X509.Validation as XV
+import Foreign (FunPtr, allocaBytes, fillBytes, freeHaskellFunPtr, nullPtr)
+import Foreign.C.Types (CInt, CSize (..))
 import qualified SMPClient
 import qualified Simplex.Messaging.Crypto as C
 import qualified Simplex.Messaging.Crypto.Lazy as LC
@@ -32,9 +36,12 @@ import Simplex.Messaging.Crypto.BBS
 import Simplex.Messaging.Crypto.Entitlement
 import Simplex.Messaging.Crypto.SNTRUP761.Bindings
 import Simplex.Messaging.Crypto.SNTRUP761.Bindings.Defines
+import Simplex.Messaging.Crypto.SNTRUP761.Bindings.FFI (c_sntrup761_keypair)
+import Simplex.Messaging.Crypto.SNTRUP761.Bindings.RNG (RNGFunc)
 import Simplex.Messaging.Encoding (Large (..), smpDecode, smpEncode)
 import Simplex.Messaging.Encoding.String (strDecode, strEncode)
 import Simplex.Messaging.Transport.Client
+import System.Timeout (timeout)
 import Test.Hspec hiding (fit, it)
 import Test.Hspec.QuickCheck (modifyMaxSuccess)
 import Test.QuickCheck hiding (Large)
@@ -113,6 +120,7 @@ cryptoTests = do
  describe "sntrup761" $ do
    it "should enc/dec key" testSNTRUP761
    it "should reject malformed KEM encodings" testSNTRUP761RejectsMalformedEncodings
+    it "should fail key generation with degenerate RNG" testSNTRUP761KeypairDegenerateRNG
  describe "BBS+" $ do
    it "should sign and verify" testBBSSignVerify
    it "should derive public key from secret key" testBBSPublicKeyDerivation
@@ -298,6 +306,26 @@ testSNTRUP761 = do
  KEMSharedKey k' <- sntrup761Dec c sk
  k' `shouldBe` k

+foreign import ccall "wrapper"
+  mkRNGFunc :: RNGFunc -> IO (FunPtr RNGFunc)
+
+testSNTRUP761KeypairDegenerateRNG :: IO ()
+testSNTRUP761KeypairDegenerateRNG = do
+  -- constant byte 0 draws invertible g = -(1 + x + ... + x^760), byte 0x20 draws g = 0
+  keypairWithConstantRNG 0 `shouldReturn` Just 0
+  keypairWithConstantRNG 0x20 `shouldReturn` Just (-1)
+  where
+    keypairWithConstantRNG :: Word8 -> IO (Maybe CInt)
+    keypairWithConstantRNG b = do
+      result <- newEmptyMVar
+      -- timeout cannot interrupt a foreign call, so the call runs in another thread
+      _ <- forkIO $
+        bracket (mkRNGFunc $ \_ sz buf -> fillBytes buf b (fromIntegral sz)) freeHaskellFunPtr $ \rng ->
+          allocaBytes c_SNTRUP761_PUBLICKEY_SIZE $ \pkPtr ->
+            allocaBytes c_SNTRUP761_SECRETKEY_SIZE $ \skPtr ->
+              c_sntrup761_keypair pkPtr skPtr nullPtr rng >>= putMVar result
+      timeout 10000000 $ takeMVar result
+
 testSNTRUP761RejectsMalformedEncodings :: IO ()
 testSNTRUP761RejectsMalformedEncodings = do
  smpDecode @KEMPublicKey (smpEncode $ Large shortPublicKey) `shouldSatisfy` isLeft
@@ -34,7 +34,7 @@ import Data.Time.Clock.System (SystemTime (..), getSystemTime)
 import SMPClient (testStoreLogFile, testStoreMsgsDir, testStoreMsgsDir2, testStoreMsgsFile, testStoreMsgsFile2)
 import Simplex.Messaging.Crypto (pattern MaxLenBS)
 import qualified Simplex.Messaging.Crypto as C
-import Simplex.Messaging.Protocol (EntityId (..), ErrorType, LinkId, Message (..), QueueLinkData, RecipientId, SParty (..), noMsgFlags)
+import Simplex.Messaging.Protocol (EncDataBytes (..), EntityId (..), ErrorType (..), LinkId, Message (..), QueueLinkData, RecipientId, SParty (..), noMsgFlags, randomMsgId)
 import Simplex.Messaging.Server (exportMessages, importMessages, printMessageStats)
 import Simplex.Messaging.Server.Env.STM (MsgStore (..), journalMsgStoreDepth, readWriteQueueStore)
 import Simplex.Messaging.Server.Expiration (ExpirationConfig (..), expireBeforeEpoch)
@@ -43,6 +43,7 @@ import Simplex.Messaging.Server.MsgStore.STM
 import Simplex.Messaging.Server.MsgStore.Types
 import Simplex.Messaging.Server.QueueStore
 import Simplex.Messaging.Server.QueueStore.QueueInfo
+import Simplex.Messaging.Server.QueueStore.Types
 import Simplex.Messaging.Server.StoreLog (closeStoreLog, logCreateQueue)
 import System.Directory (copyFile, createDirectoryIfMissing, listDirectory, removeFile, renameFile)
 import System.FilePath ((</>))
@@ -57,7 +58,6 @@ import Simplex.Messaging.Agent.Store.Postgres.Common
 import Simplex.Messaging.Agent.Store.Shared (MigrationConfirmation (..))
 import Simplex.Messaging.Server.MsgStore.Postgres
 import Simplex.Messaging.Server.QueueStore.Postgres
-import Simplex.Messaging.Server.QueueStore.Types
 import SMPClient (postgressBracket, testServerDBConnectInfo, testStoreDBOpts)
 #endif

@@ -79,6 +79,7 @@ msgStoreTests = do
        someMsgStoreTests
        it "should correctly update message counts and canWrite flag" testUpdateMessageCounts
        it "tryDelPeekMsg (ACK not from NSE) should reset message counts when queue is empty" testResetMessageCounts
+        it "should expire messages across commit batches" testExpireMessagesInBatches
 #endif
  describe "Journal message store: queue state backup expiration" $ do
    it "should remove old queue state backups" testRemoveQueueStateBackups
@@ -100,6 +101,7 @@ msgStoreTests = do
      it "should get queue and store/read messages" testGetQueue
      it "should write/ack messages" testWriteAckMessages
      it "should not fail on EOF when changing read journal" testChangeReadJournal
+      it "should not add link data to secured messaging queue" testLinkDataSecuredQueue

 -- TODO constrain to STM stores?
 withMsgStore :: MsgStoreClass s => MsgStoreConfig s -> (s -> IO ()) -> IO ()
@@ -145,7 +147,7 @@ mkMessage :: MonadIO m => ByteString -> m Message
 mkMessage body = liftIO $ do
  g <- C.newRandom
  msgTs <- getSystemTime
-  msgId <- atomically $ C.randomBytes 24 g
+  msgId <- atomically $ randomMsgId 24 g
  pure Message {msgId, msgTs, msgFlags = noMsgFlags, msgBody = C.unsafeMaxLenBS body}

 pattern Msg :: ByteString -> Maybe Message
@@ -266,6 +268,33 @@ testChangeReadJournal ms = do
    (Msg "message 5", Nothing) <- tryDelPeekMsg ms q mId5
    void $ ExceptT $ deleteQueue ms q

+testLinkDataSecuredQueue :: MsgStoreClass s => s -> IO ()
+testLinkDataSecuredQueue ms = do
+  g <- C.newRandom
+  (sKey, _) <- atomically $ C.generateAuthKeyPair C.SEd25519 g
+  let st = queueStore ms
+      ld = (EncDataBytes "fixed data", EncDataBytes "user data")
+      rndId = atomically $ EntityId <$> C.randomBytes 24 g
+  (rId, qr) <- testNewQueueRec g QMMessaging
+  (cId, cqr) <- testNewQueueRec g QMContact
+  lnkId <- rndId
+  cLnkId <- rndId
+  runRight_ $ do
+    q <- ExceptT $ addQueue ms rId qr
+    -- the handle is read before SKEY, as in a command that raced with it
+    staleQ <- ExceptT $ getQueue ms SRecipient rId
+    ExceptT $ secureQueue st q sKey
+    liftIO $ addQueueLinkData st staleQ lnkId ld `shouldReturn` Left AUTH
+    freshQ <- ExceptT $ getQueue ms SRecipient rId
+    liftIO $ getQueueLinkData st freshQ lnkId `shouldReturn` Left AUTH
+    cq <- ExceptT $ addQueue ms cId cqr
+    ExceptT $ secureQueue st cq sKey
+    ExceptT $ addQueueLinkData st cq cLnkId ld
+    ld' <- ExceptT $ getQueueLinkData st cq cLnkId
+    liftIO $ ld' `shouldBe` ld
+    void $ ExceptT $ deleteQueue ms q
+    void $ ExceptT $ deleteQueue ms cq
+
 testExportImportStore :: JournalMsgStore 'QSMemory -> IO ()
 testExportImportStore ms = do
  g <- C.newRandom
@@ -327,35 +356,34 @@ testUpdateMessageCounts ms = do
    q <- ExceptT $ addQueue ms rId qr
    let write s = writeMsg ms q True =<< mkMessage s
        hasSize = checkQueueSize ms
-    q `hasSize` (0, True, False)
+    q `hasSize` (0, True)
    Just (Message {msgId = mId1}, True) <- write "message 1"
-    q `hasSize` (1, True, True)
+    q `hasSize` (1, True)
    Just (Message {msgId = mId2}, False) <- write "message 2"
-    q `hasSize` (2, True, True)
+    q `hasSize` (2, True)
    Just (Message {msgId = mId3}, False) <- write "message 3"
-    q `hasSize` (3, True, True)
+    q `hasSize` (3, True)
    Nothing <- write "message 4"
-    q `hasSize` (4, False, True)
+    q `hasSize` (4, False)
    Msg "message 1" <- tryPeekMsg ms q
-    q `hasSize` (4, False, True)
+    q `hasSize` (4, False)
    Msg "message 1" <- tryDelMsg ms q mId1
-    q `hasSize` (3, False, True)
+    q `hasSize` (3, False)
    Msg "message 2" <- tryPeekMsg ms q
    (Msg "message 2", Msg "message 3") <- tryDelPeekMsg ms q mId2
-    q `hasSize` (2, False, True)
+    q `hasSize` (2, False)
    (Msg "message 3", Just MessageQuota {msgId = mId4}) <- tryDelPeekMsg ms q mId3
-    q `hasSize` (1, False, True)
+    q `hasSize` (1, False)
    (Just MessageQuota {}, Nothing) <- tryDelPeekMsg ms q mId4
-    q `hasSize` (0, True, False)
+    q `hasSize` (0, True)

-checkQueueSize :: PostgresMsgStore -> PostgresQueue -> (Int64, Bool, Bool) -> ExceptT ErrorType IO ()
-checkQueueSize ms q (size, canWrt, expire) = liftIO $ do
-  [(size', canWrt', expire')] <-
+checkQueueSize :: PostgresMsgStore -> PostgresQueue -> (Int64, Bool) -> ExceptT ErrorType IO ()
+checkQueueSize ms q (size, canWrt) = liftIO $ do
+  [(size', canWrt')] <-
    withTransaction (dbStore $ queueStore ms) $ \db ->
-      DB.query db "SELECT msg_queue_size, msg_can_write, msg_queue_expire FROM msg_queues WHERE recipient_id = ?" (Only (recipientId q))
+      DB.query db "SELECT msg_queue_size, msg_can_write FROM msg_queues WHERE recipient_id = ?" (Only (recipientId q))
  size' `shouldBe` size
  canWrt' `shouldBe` canWrt
-  expire' `shouldBe` expire

 testResetMessageCounts :: PostgresMsgStore -> IO ()
 testResetMessageCounts ms = do
@@ -369,25 +397,63 @@ testResetMessageCounts ms = do
    Just (Message {msgId = mId2}, False) <- write "message 2"
    Just (Message {msgId = mId3}, False) <- write "message 3"
    Nothing <- write "message 4"
-    q `hasSize` (4, False, True)
+    q `hasSize` (4, False)
    liftIO $ setIncorrectSize q (10, True)
    Nothing <- write "message 5"
-    q `hasSize` (11, False, True)
+    q `hasSize` (11, False)
    (Msg "message 1", Msg "message 2") <- tryDelPeekMsg ms q mId1
-    q `hasSize` (10, False, True)
+    q `hasSize` (10, False)
    (Msg "message 2", Msg "message 3") <- tryDelPeekMsg ms q mId2
-    q `hasSize` (9, False, True)
+    q `hasSize` (9, False)
    (Msg "message 3", Just MessageQuota {msgId = mId4}) <- tryDelPeekMsg ms q mId3
-    q `hasSize` (8, False, True)
+    q `hasSize` (8, False)
    (Just MessageQuota {}, Just MessageQuota {msgId = mId5}) <- tryDelPeekMsg ms q mId4
-    q `hasSize` (7, False, True)
+    q `hasSize` (7, False)
    (Just MessageQuota {}, Nothing) <- tryDelPeekMsg ms q mId5
-    q `hasSize` (0, True, False) -- reset
+    q `hasSize` (0, True) -- reset
  where
    setIncorrectSize :: PostgresQueue -> (Int64, Bool) -> IO ()
    setIncorrectSize q (size, canWrt) =
      void $ withTransaction (dbStore $ queueStore ms) $ \db ->
        DB.execute db "UPDATE msg_queues SET msg_queue_size = ?, msg_can_write = ? WHERE recipient_id = ?" (size, canWrt, recipientId q)
+
+testExpireMessagesInBatches :: PostgresMsgStore -> IO ()
+testExpireMessagesInBatches ms = do
+  g <- C.newRandom
+  emptiedQs <- replicateM emptiedCount $ newQueue g
+  partialQs <- replicateM partialCount $ newQueue g
+  overQuotaQs <- replicateM overQuotaCount $ newQueue g
+  quotaMsgs <- runRight $ do
+    forM_ (emptiedQs <> partialQs) $ \q -> void $ write q "old 1"
+    forM_ emptiedQs $ \q -> void $ write q "old 2"
+    mapM fillPastQuota overQuotaQs
+  -- msg_ts has second granularity, so the recent messages need a new second to be kept
+  threadDelay 1100000
+  boundary <- systemSeconds <$> getSystemTime
+  runRight_ $ forM_ partialQs $ \q -> void $ write q "recent"
+
+  MessageStats {expiredMsgsCount, storedMsgsCount, storedQueues} <- expireOldMessages False ms boundary 0
+  expiredMsgsCount `shouldBe` (emptiedCount * 2 + partialCount + sum quotaMsgs)
+  storedMsgsCount `shouldBe` (partialCount + overQuotaCount) -- recent messages and quota markers
+  storedQueues `shouldBe` (emptiedCount + partialCount + overQuotaCount)
+  runRight_ $ do
+    forM_ emptiedQs $ \q -> checkQueueSize ms q (0, True)
+    forM_ partialQs $ \q -> checkQueueSize ms q (1, True)
+    -- the quota marker is never expired, and the queue stays blocked until it is acked
+    forM_ overQuotaQs $ \q -> checkQueueSize ms q (1, False)
+  where
+    -- expire_old_messages pages through expired messages and commits per page, so these
+    -- counts put a page boundary inside each group of queues.
+    emptiedCount = 120 :: Int
+    partialCount = 40 :: Int
+    overQuotaCount = 10 :: Int
+    newQueue g = do
+      (rId, qr) <- testNewQueueRec g QMMessaging
+      runRight $ ExceptT $ addQueue ms rId qr
+    write q s = writeMsg ms q True =<< mkMessage s
+    fillPastQuota q = go 0
+      where
+        go n = write q "fill" >>= maybe (pure n) (const $ go (n + 1))
 #endif

 testQueueState :: JournalMsgStore s -> IO ()
@@ -2,15 +2,18 @@
 {-# LANGUAGE NamedFieldPuns #-}
 {-# LANGUAGE OverloadedLists #-}
 {-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE PatternSynonyms #-}
 {-# LANGUAGE TypeApplications #-}
 {-# OPTIONS_GHC -fno-warn-ambiguous-fields #-}

 module CoreTests.SOCKSSettings where

 import Network.Socket (SockAddr (..), tupleToHostAddress)
+import Simplex.Messaging.Agent.Client (ipAddressProtected)
 import Simplex.Messaging.Client
+import qualified Simplex.Messaging.Crypto as C
 import Simplex.Messaging.Encoding.String
-import Simplex.Messaging.Protocol (ErrorType)
+import Simplex.Messaging.Protocol (ErrorType, pattern SMPServer)
 import Simplex.Messaging.Transport.Client
 import Test.Hspec hiding (fit, it)
 import Util
@@ -19,6 +22,7 @@ socksSettingsTests :: Spec
 socksSettingsTests = do
  describe "hostMode and requiredHostMode settings" testHostMode
  describe "socksMode setting, independent of hostMode setting" testSocksMode
+  describe "ipAddressProtected, consistent with chosen host and socksMode" testIPAddressProtected
  describe "socks proxy address encoding" testSocksProxyEncoding

 testPublicHost :: TransportHost
@@ -94,6 +98,19 @@ testSocksMode = do
      let TransportClientConfig {socksProxy} = transportClientConfig cfg NRMInteractive host False Nothing
       in socksProxy

+testIPAddressProtected :: Spec
+testIPAddressProtected = do
+  it "should be protected if SOCKS proxy is used for the chosen host" $ do
+    protected SMAlways HMOnionViaSocks [testPublicHost] `shouldBe` True
+    protected SMOnion HMOnionViaSocks [testPublicHost, testOnionHost] `shouldBe` True
+    protected SMOnion HMPublic [testOnionHost] `shouldBe` True
+  it "should not be protected if SOCKS proxy is not used for the chosen host" $ do
+    protected SMOnion HMOnionViaSocks [testPublicHost] `shouldBe` False
+    protected SMOnion HMPublic [testPublicHost, testOnionHost] `shouldBe` False
+  where
+    protected socksMode hostMode hosts =
+      ipAddressProtected defaultNetworkConfig {socksProxy = Just defaultSocksProxyWithAuth, socksMode, hostMode} (SMPServer hosts "" (C.KeyHash ""))
+
 testSocksProxyEncoding :: Spec
 testSocksProxyEncoding = do
  it "should decode SOCKS proxy with isolate-by-auth mode" $ do
--- a/Show More
+++ b/Show More
Author	SHA1	Message	Date
Evgeny Poberezkin	cba1382356	7.1.0.11	2026-10-11 22:33:06 +01:00
EvgenyandEvgeny @ SimpleX Chat	b5e8a4b8cc	fix tests on ghc 8.10.7 (#1939 ) * fix tests on ghc 8.10.7 * fix test * fix schema dump test --------- Co-authored-by: Evgeny @ SimpleX Chat <[email protected]>	2026-10-11 20:36:51 +01:00
EvgenyandEvgeny @ SimpleX Chat	3db4029bb9	ci: build cache (#1938 ) * ci: build cache * update build job * rename steps, cache all builds, patch timestamps for ghc 8.10.7 * refactor, save O0 caches in master and stable builds * update build to include toolchain fingerprint * do not save cache on exact match * remove caching docker from prs --------- Co-authored-by: Evgeny @ SimpleX Chat <[email protected]>	2026-10-11 11:52:24 +01:00
EvgenyandEvgeny @ SimpleX Chat	8a80727fa5	smp server: delayed AUTH responses (#1937 ) * smp server: delayed AUTH responses * plan * update * simplify * simplify * stat when sent without delay * update schema * round up response time to the nearest delay multiple --------- Co-authored-by: Evgeny @ SimpleX Chat <[email protected]>	2026-10-11 07:37:33 +01:00
EvgenyandEvgeny @ SimpleX Chat	a2f985dc68	agent: prepare invitation link, create ratchet when connection is prepared (#1880 ) * agent: prepare invitation link * simplify * refactor * fix * change min SMP version to 15 * remove dead code for SMP version <= 15 * update * diff * create ratchet when connection is prepared * createRatchetIfNotExists * clean up, only check client notices for contacts, fix orphan record * simplify * refactor --------- Co-authored-by: Evgeny @ SimpleX Chat <[email protected]>	2026-10-10 23:15:19 +01:00
EvgenyandEvgeny @ SimpleX Chat	c18e0297c4	agent: migration to add index to read queues (#1934 ) * agent: migration to add index to read queues * update postgres schema --------- Co-authored-by: Evgeny @ SimpleX Chat <[email protected]>	2026-10-08 17:07:55 +01:00
EvgenyandEvgeny @ SimpleX Chat	e24d537eaa	agent: fix race when switching reception to the new queue (#1933 ) * agent: fix race when switching reception to the new queue * return bool --------- Co-authored-by: Evgeny @ SimpleX Chat <[email protected]>	2026-10-08 16:03:06 +01:00
sh	7754f8624e	smp-server: copy entity IDs out of received block (#1906 )	2026-10-08 15:28:38 +01:00
EvgenyandEvgeny @ SimpleX Chat	8d81f775b1	smp protocol: require fixed size corr ID when used as nonce, and min size msg ID to use as nonce (#1925 ) * smp protocol: require fixed size corr ID when used as nonce, and min size msg ID to use as nonce * simpler * fixes * randomMsgId --------- Co-authored-by: Evgeny @ SimpleX Chat <[email protected]>	2026-10-08 09:32:11 +01:00
EvgenyandEvgeny @ SimpleX Chat	c0a1b7bd2d	agent: fail database transaction instantly when database is closed, prevent race conditions in command processing, fix race when uploading files (#1885 ) * agent: fail database transaction instantly when database is closed * update direct-sqlcipher * update direct-sqlcipher, fixes * autoincrement command ID --------- Co-authored-by: Evgeny @ SimpleX Chat <[email protected]>	2026-10-06 13:01:55 +01:00
EvgenyandEvgeny @ SimpleX Chat	4ab5376a6e	smp: reduce min supported version to 15 (short links support, 3/30/2025) (#1931 ) Co-authored-by: Evgeny @ SimpleX Chat <[email protected]>	2026-10-05 11:31:57 +01:00
Evgeny	aaffb5b07d	Merge pull request #1922 from simplex-chat/ratchet Improve double ratchet	2026-10-05 08:07:04 +01:00
EvgenyandEvgeny @ SimpleX Chat	65893a359a	agent: resolve potential race conditions in double ratchet (#1923 ) * agent: resolve potential race conditions in double ratchet * update * improve * diff * diff * diff * simpler * more races --------- Co-authored-by: Evgeny @ SimpleX Chat <[email protected]>	2026-10-04 22:28:50 +01:00
EvgenyandEvgeny @ SimpleX Chat	fcc5670ae2	agent: keep ratchet hashes for connection lifetime, up to some cap, to prevent replay of expired ratchets (#1893 ) * agent: keep ratchet hashes for connection lifetime, to prevent replay of expired ratchets * cap * simpler * simpler2 * split * one query * simplify * performance * migration * fix schema * comment * improve --------- Co-authored-by: Evgeny @ SimpleX Chat <[email protected]>	2026-10-04 14:43:21 +01:00
Evgenyandshum	18440c0d17	smp-server: check queue is not secured in link store (#1917 ) Co-authored-by: shum <[email protected]>	2026-10-04 13:41:48 +01:00
EvgenyandEvgeny @ SimpleX Chat	64c5d19fc4	agent: aggregate cap on skipped message keys (#1903 ) * agent: aggregate cap on skipped message keys * migration * update migration --------- Co-authored-by: Evgeny @ SimpleX Chat <[email protected]>	2026-10-04 10:18:41 +01:00
EvgenyandEvgeny @ SimpleX Chat	e11dfb985d	consider IP address protected only if it is used for the chosen host (#1895 ) * consider IP address protected only if it is used for the chosen host * simplify * simplify * simplify --------- Co-authored-by: Evgeny @ SimpleX Chat <[email protected]>	2026-10-03 22:45:44 +01:00
Evgenyandshum	76248dd767	sntrup761: bound KeyGen retries on R3 inversion (#1918 ) Co-authored-by: shum <[email protected]>	2026-10-03 17:01:36 +01:00
brenzi	9c641fed91	reject e2e params with kem_ct and without kem_key (#1901 )	2026-10-03 15:10:42 +01:00
sh	91e070cb5e	crypto: document 16-byte GCM IV in double ratchet (#1914 )	2026-10-03 15:00:18 +01:00
sh	9fe3745401	docs: use role names for key exchange parties (#1912 )	2026-10-03 14:59:22 +01:00
EvgenyandEvgeny @ SimpleX Chat	24036368f8	xrcp: limit multicast validity time window (#1899 ) Co-authored-by: Evgeny @ SimpleX Chat <[email protected]>	2026-10-03 14:51:48 +01:00
sh	acd5c0f530	docs: add cryptographic primitive registry (#1913 )	2026-10-03 14:21:21 +01:00
EvgenyandEvgeny @ SimpleX Chat	ead8f10f26	smp protocol: bind agreed version of forwarded command (#1915 ) * smp protocol: bind agreed version of forwarded command * refactor * pass proxied relay version range via config * simplify * refactor * packZipWith --------- Co-authored-by: Evgeny @ SimpleX Chat <[email protected]>	2026-10-03 08:56:19 +01:00
sh	053e83b704	resolver: multicall reads, keep-alive, workers and structured logs (#1883 ) * resolver: queue up to 128 pending connections * resolver: reuse connections to the node * resolver: read each round in one multicall * resolver: run worker processes, log durations * resolver: keep smp-server connections alive * resolver: test with pytest, lock dependencies * resolver: structured logs and real client addresses * resolver: refuse requests with a body * resolver: harden pool, health and odd answers * resolver: pin images, rotate logs * resolver: stricter body check, redact RPC URL * resolver: ship .env as .env.example * resolver: pass settings from .env * resolver: name the image snrc-resolve:local	2026-10-01 09:10:42 +01:00
sh	234b5cd856	smp-server: rework message expiration (#1873 ) * smp server: rework message expiration * smp server: paginate message expiration sweep	2026-10-01 09:08:16 +01:00
Evgeny Poberezkin	38fdc0c544	7.1.0.10	2026-09-30 13:03:16 +01:00
EvgenyandEvgeny @ SimpleX Chat	b4c288c597	docs: clarify security model (#1902 ) Co-authored-by: Evgeny @ SimpleX Chat <[email protected]>	2026-09-30 10:18:52 +01:00
EvgenyandEvgeny @ SimpleX Chat	0e1ecdcff6	xftp server: validate paths in store log (#1894 ) Co-authored-by: Evgeny @ SimpleX Chat <[email protected]>	2026-09-30 09:36:45 +01:00
EvgenyandEvgeny @ SimpleX Chat	c1776dc5a4	server: improve control port auth (#1898 ) Co-authored-by: Evgeny @ SimpleX Chat <[email protected]>	2026-09-30 09:04:28 +01:00
EvgenyandEvgeny @ SimpleX Chat	e2df2e1b7c	docs: update SMP protocol (#1900 ) Co-authored-by: Evgeny @ SimpleX Chat <[email protected]>	2026-09-30 08:10:35 +01:00
EvgenyandEvgeny @ SimpleX Chat	267e2e0727	agent: fix ratchet - dont save if body auth failed (#1892 ) Co-authored-by: Evgeny @ SimpleX Chat <[email protected]>	2026-09-29 21:32:21 +01:00
EvgenyandEvgeny @ SimpleX Chat	551a79d99b	smp server: validate client version in forwarded command (#1890 ) Co-authored-by: Evgeny @ SimpleX Chat <[email protected]>	2026-09-29 19:52:15 +01:00
EvgenyandEvgeny @ SimpleX Chat	972e50e768	docs: update XRCP doc to make code verification optional for known connections (#1891 ) Co-authored-by: Evgeny @ SimpleX Chat <[email protected]>	2026-09-29 18:08:54 +01:00
Evgeny Poberezkin	5eecd99bc2	7.1.0.9	2026-09-26 12:52:57 +01:00
Narasimha-sc Evgeny Poberezkin Evgeny @ SimpleX Chat	69eb28b3ab	agent: share server value across subscription rows of server-keyed queries (#1877 ) * agent: share server value across subscription rows of server-keyed queries * reduce fields in query --------- Co-authored-by: Evgeny Poberezkin <[email protected]> Co-authored-by: Evgeny @ SimpleX Chat <[email protected]>	2026-09-26 12:05:20 +01:00