Screening events from the local proxy, and the mode each event came from

* Guide the user to the extension approval switch

* Allow uninstalling while the extension waits for approval

* Show the approval instruction in larger orange text

* Leave opening System Settings to the macOS alert

* Shrink the approval instruction slightly

* Hide the setup log

* Add a button that opens System Settings while approval is pending

core/src/aliasing/forward.rs

@@ -82,7 +82,7 @@ async fn handle(req: Request, firewall: &Firewall) -> Result<Response, Infallibl
     };
 
     let reason = policies::screen(&url, firewall).await;
-    telemetry::screened(firewall, &url, reason.is_some());
+    telemetry::screened(firewall, &url, reason.as_deref());
     if let Some(reason) = reason {
         warn!(method = %req.method(), %url, %reason, "blocked");
         return Ok(blocked(&reason));

core/src/main.rs

@@ -56,6 +56,7 @@ fn options() -> Command {
 }
 
 fn serve() -> ! {
+    telemetry::set_mode("proxy");
     let config = load();
     let port = config.port;
     print_setup(&config);
@@ -83,6 +84,7 @@ fn uninstall() -> ! {
 }
 
 fn run(invocation: Invocation) -> ! {
+    telemetry::set_mode("wrapper");
     let command = &invocation.program;
     let port = match aliasing::spawn(0, load()) {
         Ok(port) => port,

core/src/mitm/screen.rs

@@ -37,7 +37,7 @@ where
     async fn serve(&self, req: Request) -> Result<Response, Self::Error> {
         if let Some(url) = https_url(&req) {
             let reason = policies::screen(&url, &self.firewall).await;
-            telemetry::screened(&self.firewall, &url, reason.is_some());
+            telemetry::screened(&self.firewall, &url, reason.as_deref());
             if let Some(reason) = reason {
                 warn!(%url, "blocked by firewall: {reason}");
                 return Ok(blocked(&reason));

core/src/os/macos/mod.rs

@@ -98,6 +98,7 @@ impl TransparentProxyHandlerFactory for Factory {
 }
 
 fn handler(exec: Executor) -> Result<Handler, BoxError> {
+    telemetry::set_mode("extension");
     telemetry::heartbeat();
     let config = FirewallConfig::load().inspect_err(|_| telemetry::error("config"))?;
     let firewall = Arc::new(Firewall::new(config));

core/src/os/macos/uninstall.rs

@@ -26,10 +26,8 @@ pub fn uninstall() -> Result<(), BoxError> {
         Err(error) if error.code() == errSecItemNotFound => false,
         Err(error) => return Err(error.into()),
     };
-    if system_keychain::load_secret(KEYCHAIN_SERVICE, KEYCHAIN_ACCOUNT)?.is_some() {
-        system_keychain::delete_secret(KEYCHAIN_SERVICE, KEYCHAIN_ACCOUNT)?;
-        removed = true;
-    }
+    // Reading a secret's data is limited to the extension, so delete without checking it exists.
+    system_keychain::delete_secret(KEYCHAIN_SERVICE, KEYCHAIN_ACCOUNT)?;
     EnclaveKey::delete()?;
     for path in [CA_FILE, ENV_AGENT] {
         match std::fs::remove_file(path) {

core/src/policies/mod.rs

@@ -72,6 +72,9 @@ pub async fn screen(url: &str, firewall: &Firewall) -> Option<String> {
         Some((_, Verdict::Deny(reason))) => {
             Some(format!("{} {reason}", pkg.label()))
         }
+        Some((filter, Verdict::Unknown(e))) if !firewall.config.fail_open => {
+            Some(format!("{} could not be checked by {filter} ({e})", pkg.label()))
+        }
         _ => None,
     }
 }

core/src/proxy/mod.rs

@@ -1,6 +1,6 @@
 use crate::http::{blocked, reply, text};
 use crate::policies::{self, Check, Decision};
-use crate::{Firewall, FirewallConfig};
+use crate::{telemetry, Firewall, FirewallConfig};
 use rama::http::body::util::BodyExt;
 use rama::http::client::EasyHttpWebClient;
 use rama::http::header::CONTENT_TYPE;
@@ -19,6 +19,7 @@ pub fn serve(config: FirewallConfig) -> std::io::Result<()> {
     bound.set_nonblocking(true)?;
     crate::runtime()?.block_on(async move {
         let firewall = Arc::new(Firewall::new(config));
+        telemetry::heartbeat();
         let exec = Executor::default();
         let listener = TcpListener::try_from_std_tcp_listener(bound, exec.clone())?;
         let server = HttpServer::auto(exec).service(service_fn(move |req: Request| {
@@ -44,6 +45,7 @@ async fn screen(target: String, firewall: &Firewall) -> Response {
         }
         Decision::Block { eco, pkg, filter, reason } => {
             let reason = format!("{} {reason}", pkg.label());
+            telemetry::screened_package(eco, &pkg, Some(&reason));
             warn!(%eco, %filter, "blocked by firewall: {reason}");
             blocked(&reason)
         }
@@ -51,9 +53,11 @@ async fn screen(target: String, firewall: &Firewall) -> Response {
             match &check {
                 Check::NoPackage => {}
                 Check::Allowed(pkg) => {
+                    telemetry::screened_package(target.eco, pkg, None);
                     info!(eco = %target.eco, pkg = %pkg.label(), "cleared by every filter")
                 }
                 Check::Unverified { pkg, filter, error } => {
+                    telemetry::screened_package(target.eco, pkg, None);
                     info!(pkg = %pkg.label(), %filter, %error, "filter could not check, allowing")
                 }
             }

core/src/telemetry.rs

@@ -1,10 +1,11 @@
+use crate::policies::Package;
 use crate::{Firewall, FirewallConfig};
 use rama::http::client::EasyHttpWebClient;
 use rama::http::header::CONTENT_TYPE;
 use rama::http::service::client::HttpClientExt;
 use rama::rt::blocking::Runtime;
 use serde_json::{json, Value};
-use std::sync::{LazyLock, Mutex};
+use std::sync::{LazyLock, Mutex, OnceLock};
 use std::time::Duration;
 use time::format_description::well_known::Rfc3339;
 use time::OffsetDateTime;
@@ -29,29 +30,40 @@ static TELEMETRY: LazyLock<Option<Telemetry>> = LazyLock::new(|| {
     })
 });
 
+/// How the firewall is running: "extension", "wrapper" or "proxy".
+static MODE: OnceLock<&'static str> = OnceLock::new();
+
 struct Telemetry {
     key: &'static str,
     session: String,
     events: Mutex<Vec<Value>>,
 }
 
-pub fn screened(firewall: &Firewall, url: &str, blocked: bool) {
+pub fn screened(firewall: &Firewall, url: &str, reason: Option<&str>) {
     if TELEMETRY.is_none() {
         return;
     }
     let Some((registry, rest)) = firewall.match_on(url, |r| r.upstream) else {
         return;
     };
-    let Some(pkg) = firewall.resolve(registry, rest).pkg else {
-        return;
-    };
-    let mut properties = json!({ "eco": registry.eco, "blocked": blocked });
-    if blocked {
+    if let Some(pkg) = firewall.resolve(registry, rest).pkg {
+        screened_package(registry.eco, &pkg, reason);
+    }
+}
+
+pub fn screened_package(eco: &str, pkg: &Package, reason: Option<&str>) {
+    let mut properties = json!({ "eco": eco, "blocked": reason.is_some() });
+    if let Some(reason) = reason {
         properties["package"] = pkg.label().into();
+        properties["reason"] = reason.into();
     }
     record("package_screened", properties);
 }
 
+pub fn set_mode(mode: &'static str) {
+    MODE.set(mode).ok();
+}
+
 pub fn error(kind: &'static str) {
     record("error", json!({ "kind": kind }));
 }
@@ -81,6 +93,7 @@ pub fn flush() {
 fn record(event: &str, mut properties: Value) {
     let Some(telemetry) = &*TELEMETRY else { return };
     properties["distinct_id"] = telemetry.session.clone().into();
+    properties["mode"] = MODE.get().copied().into();
     properties["os"] = std::env::consts::OS.into();
     properties["arch"] = std::env::consts::ARCH.into();
     properties["$process_person_profile"] = false.into();

core/tests/config.rs

@@ -1,6 +1,6 @@
 use firewall::config::path;
 use firewall::policies::filters::consult;
-use firewall::policies::Package;
+use firewall::policies::{screen, Package};
 use firewall::{Firewall, FirewallConfig};
 
 #[test]
@@ -31,3 +31,12 @@ async fn an_allowed_version_skips_the_filters() {
     assert!(consult(&firewall, registry, &pkg("0.20.0")).await.is_none());
     assert!(consult(&firewall, registry, &pkg("0.21.0")).await.is_some());
 }
+
+#[tokio::test]
+async fn failing_closed_blocks_what_could_not_be_checked() {
+    let config = r#"{"fail_open": false, "denylist": {"base": "http://127.0.0.1:1"}}"#;
+    let firewall = Firewall::new(serde_json::from_str(config).expect("parses"));
+    let url = "https://registry.npmjs.org/left-pad/-/left-pad-1.3.0.tgz";
+    let blocked = screen(url, &firewall).await.unwrap_or_default();
+    assert!(blocked.contains("could not be checked"), "{blocked:?}");
+}

macos/App/Assets.xcassets/AppIcon.appiconset/Contents.json

@@ -0,0 +1,68 @@
+{
+  "images": [
+    {
+      "idiom": "mac",
+      "size": "16x16",
+      "scale": "1x",
+      "filename": "icon_16.png"
+    },
+    {
+      "idiom": "mac",
+      "size": "16x16",
+      "scale": "2x",
+      "filename": "icon_32.png"
+    },
+    {
+      "idiom": "mac",
+      "size": "32x32",
+      "scale": "1x",
+      "filename": "icon_32.png"
+    },
+    {
+      "idiom": "mac",
+      "size": "32x32",
+      "scale": "2x",
+      "filename": "icon_64.png"
+    },
+    {
+      "idiom": "mac",
+      "size": "128x128",
+      "scale": "1x",
+      "filename": "icon_128.png"
+    },
+    {
+      "idiom": "mac",
+      "size": "128x128",
+      "scale": "2x",
+      "filename": "icon_256.png"
+    },
+    {
+      "idiom": "mac",
+      "size": "256x256",
+      "scale": "1x",
+      "filename": "icon_256.png"
+    },
+    {
+      "idiom": "mac",
+      "size": "256x256",
+      "scale": "2x",
+      "filename": "icon_512.png"
+    },
+    {
+      "idiom": "mac",
+      "size": "512x512",
+      "scale": "1x",
+      "filename": "icon_512.png"
+    },
+    {
+      "idiom": "mac",
+      "size": "512x512",
+      "scale": "2x",
+      "filename": "icon_1024.png"
+    }
+  ],
+  "info": {
+    "author": "xcode",
+    "version": 1
+  }
+}

macos/App/Assets.xcassets/Contents.json

@@ -0,0 +1,3 @@
+{
+  "info" : { "author" : "xcode", "version" : 1 }
+}

macos/App/ContentView.swift

@@ -10,11 +10,9 @@ struct ContentView: View {
             Divider()
             steps
             Divider()
-            transcript
-            Divider()
             footer
         }
-        .frame(width: 540, height: 560)
+        .frame(width: 540)
         .task { await model.refresh() }
         .onAppear(perform: recenterIfOffscreen)
         .onChange(of: model.completed) { done in
@@ -38,9 +36,11 @@ struct ContentView: View {
 
     private var header: some View {
         HStack(spacing: 14) {
-            Image(systemName: "shield.lefthalf.filled")
-                .font(.system(size: 34, weight: .light))
-                .foregroundStyle(.tint)
+            Image(nsImage: NSImage(named: "logo-transparent")!)
+                .renderingMode(.template)
+                .resizable()
+                .scaledToFit()
+                .frame(height: 40)
             VStack(alignment: .leading, spacing: 3) {
                 Text("Firewall").font(.title2.weight(.semibold))
                 Text("Screens package downloads before they reach your machine.")
@@ -70,27 +70,6 @@ struct ContentView: View {
         .padding(20)
     }
 
-    private var transcript: some View {
-        ScrollViewReader { proxy in
-            ScrollView {
-                VStack(alignment: .leading, spacing: 2) {
-                    ForEach(model.transcript.indices, id: \.self) { line in
-                        Text(model.transcript[line])
-                            .font(.system(.caption, design: .monospaced))
-                            .foregroundStyle(.secondary)
-                            .frame(maxWidth: .infinity, alignment: .leading)
-                            .id(line)
-                    }
-                }
-                .padding(12)
-            }
-            .onChange(of: model.transcript.count) { count in
-                proxy.scrollTo(count - 1)
-            }
-        }
-        .frame(maxHeight: .infinity)
-    }
-
     private var footer: some View {
         HStack {
             if model.busy { ProgressView().controlSize(.small) }
@@ -105,8 +84,11 @@ struct ContentView: View {
                     .font(.callout)
             }
             Spacer()
+            if model.awaitingApproval {
+                Button("Open System Settings") { model.openApprovalSettings() }
+            }
             Button("Uninstall") { Task { await model.uninstall() } }
-                .disabled(model.busy)
+                .disabled(model.busy && !model.awaitingApproval)
             Button("Install") { Task { await model.install() } }
                 .keyboardShortcut(.defaultAction)
                 .disabled(model.busy || model.completed)
@@ -129,9 +111,10 @@ private struct StepRow: View {
                 Text(title).font(.body.weight(.medium))
                 Text(note).font(.caption).foregroundStyle(.secondary)
                 Text(status.detail)
-                    .font(.caption)
+                    .font(font)
                     .foregroundStyle(tint)
                     .textSelection(.enabled)
+                    .fixedSize(horizontal: false, vertical: true)
             }
             Spacer()
         }
@@ -146,7 +129,7 @@ private struct StepRow: View {
                 .foregroundStyle(.secondary)
                 .frame(width: 20, height: 20)
                 .overlay(Circle().strokeBorder(.secondary.opacity(0.4)))
-        case .running:
+        case .running, .needsAction:
             ProgressView().controlSize(.small)
         case .done:
             Image(systemName: "checkmark.circle.fill").foregroundStyle(.green)
@@ -155,9 +138,15 @@ private struct StepRow: View {
         }
     }
 
+    private var font: Font {
+        if case .needsAction = status { return .system(size: 14) }
+        return .caption
+    }
+
     private var tint: Color {
         switch status {
         case .pending, .running: return .secondary
+        case .needsAction: return .orange
         case .done: return .green
         case .failed: return .orange
         }

macos/App/FirewallModel.swift

@@ -7,13 +7,15 @@ import SystemExtensions
 enum StepStatus: Equatable {
     case pending
     case running(String)
+    /// Waiting on the user to do something outside the app.
+    case needsAction(String)
     case done(String)
     case failed(String)
 
     var detail: String {
         switch self {
         case .pending: return "Not started"
-        case let .running(text), let .done(text), let .failed(text): return text
+        case let .running(text), let .needsAction(text), let .done(text), let .failed(text): return text
         }
     }
 
@@ -43,14 +45,15 @@ final class FirewallModel: NSObject, ObservableObject {
     @Published private(set) var extensionStep = StepStatus.pending
     @Published private(set) var screeningStep = StepStatus.pending
     @Published private(set) var trustStep = StepStatus.pending
-    @Published private(set) var busy = false
+    @Published private var operations = 0
+    var busy: Bool { operations > 0 }
+    @Published private(set) var awaitingApproval = false
     @Published private(set) var completed = false
     @Published private(set) var removed = false
-    @Published private(set) var transcript: [String] = []
     @Published private(set) var screening = false
 
     private let logger = Logger(subsystem: FirewallIDs.appBundleID, category: "installer")
-    private var pendingRequest: CheckedContinuation<Void, Error>?
+    private var pendingRequest: (request: OSSystemExtensionRequest, continuation: CheckedContinuation<Void, Error>)?
     private var statusObserver: NSObjectProtocol?
     // NE only posts status notifications for connections that are still referenced.
     @Published private var watched: NETransparentProxyManager?
@@ -88,8 +91,8 @@ final class FirewallModel: NSObject, ObservableObject {
     }
 
     func install() async {
-        busy = true
-        defer { busy = false }
+        operations += 1
+        defer { operations -= 1 }
         removed = false
 
         guard CompetingExtensions.confirmInstall() else {
@@ -115,10 +118,14 @@ final class FirewallModel: NSObject, ObservableObject {
 
     /// After the admin gate, every stage runs even if an earlier one fails, so a partial uninstall never strands the rest.
     func uninstall() async {
-        busy = true
-        defer { busy = false }
+        operations += 1
+        defer { operations -= 1 }
         completed = false
         removed = false
+        // Stop waiting on an activation the user never approved; the deactivation below withdraws it.
+        if let pending = pendingRequest {
+            finishRequest(pending.request, .failure(CocoaError(.userCancelled)))
+        }
 
         // Install needs admin, so uninstall does too: untrusting the CA prompts for it, and a cancel stops here.
         guard await untrustAuthorities() else {
@@ -151,16 +158,16 @@ final class FirewallModel: NSObject, ObservableObject {
 
     /// Restarting the tunnel rebuilds the provider, which is what makes it re-read the config.
     func restart() async {
-        busy = true
-        defer { busy = false }
+        operations += 1
+        defer { operations -= 1 }
         guard await stage(\.screeningStep, running: "Restarting screening", work: restartScreening) else { return }
         // A restart can mint a new CA when the screened hosts change.
         _ = await stage(\.trustStep, running: "Waiting for the extension's CA", work: trustCertificateAuthority)
     }
 
     func setEnabled(_ enabled: Bool) async {
-        busy = true
-        defer { busy = false }
+        operations += 1
+        defer { operations -= 1 }
         if enabled {
             _ = await stage(\.screeningStep, running: "Starting screening", work: startScreening)
         } else {
@@ -168,6 +175,14 @@ final class FirewallModel: NSObject, ObservableObject {
         }
     }
 
+    func openApprovalSettings() {
+        var pane = "x-apple.systempreferences:com.apple.preference.security"
+        if #available(macOS 15, *) {
+            pane = "x-apple.systempreferences:com.apple.ExtensionsPreferences?extensionPointIdentifier=com.apple.system_extension.network_extension"
+        }
+        if let url = URL(string: pane) { NSWorkspace.shared.open(url) }
+    }
+
     private func stage(_ step: ReferenceWritableKeyPath<FirewallModel, StepStatus>,
                        running: String,
                        work: @MainActor () async throws -> String) async -> Bool {
@@ -212,6 +227,9 @@ final class FirewallModel: NSObject, ObservableObject {
                 forExtensionWithIdentifier: FirewallIDs.extensionBundleID, queue: .main))
             extensionStep = .pending
             log("System extension deactivated, macOS finishes removing it on the next reboot")
+        } catch OSSystemExtensionError.extensionNotFound {
+            extensionStep = .pending
+            log("No system extension to deactivate")
         } catch {
             extensionStep = .failed(error.localizedDescription)
             log("Deactivation failed: \(error.localizedDescription)")
@@ -265,14 +283,18 @@ final class FirewallModel: NSObject, ObservableObject {
     private func submit(_ request: OSSystemExtensionRequest) async throws {
         request.delegate = self
         try await withCheckedThrowingContinuation { (continuation: CheckedContinuation<Void, Error>) in
-            pendingRequest = continuation
+            pendingRequest = (request, continuation)
             OSSystemExtensionManager.shared.submitRequest(request)
         }
     }
 
-    private func finishRequest(_ result: Result<Void, Error>) {
-        pendingRequest?.resume(with: result)
+    /// Callbacks for an abandoned request can still arrive, so only the pending one is finished.
+    private func finishRequest(_ request: OSSystemExtensionRequest, _ result: Result<Void, Error>) {
+        guard let pending = pendingRequest, pending.request === request else { return }
         pendingRequest = nil
+        awaitingApproval = false
+        NSApp.activate(ignoringOtherApps: true)
+        pending.continuation.resume(with: result)
     }
 
     // MARK: - Network extension
@@ -388,7 +410,6 @@ final class FirewallModel: NSObject, ObservableObject {
     }
 
     private func log(_ line: String) {
-        transcript.append("\(Date().formatted(date: .omitted, time: .standard))  \(line)")
         logger.info("\(line, privacy: .public)")
     }
 }
@@ -402,12 +423,14 @@ extension FirewallModel: OSSystemExtensionRequestDelegate {
 
     nonisolated func requestNeedsUserApproval(_ request: OSSystemExtensionRequest) {
         Task { @MainActor in
-            extensionStep = .running("Approve Firewall in System Settings › General › Login Items & Extensions")
-            log("Waiting for user approval")
-            // Only MDM can pre-approve a system extension, so take them to the switch.
-            if let pane = URL(string: "x-apple.systempreferences:com.apple.ExtensionsPreferences?extensionPointIdentifier=com.apple.system_extension.network_extension") {
-                NSWorkspace.shared.open(pane)
+            // macOS shows its own alert that opens System Settings; this says what to do there.
+            var instruction = "In System Settings › Privacy & Security, click Allow for StrixFirewall"
+            if #available(macOS 15, *) {
+                instruction = "In System Settings › General › Login Items & Extensions, click Network Extensions and turn on StrixFirewall"
             }
+            extensionStep = .needsAction(instruction)
+            awaitingApproval = true
+            log("Waiting for user approval")
         }
     }
 
@@ -417,12 +440,12 @@ extension FirewallModel: OSSystemExtensionRequestDelegate {
             if result == .willCompleteAfterReboot {
                 log("Extension will finish installing after a reboot")
             }
-            finishRequest(.success(()))
+            finishRequest(request, .success(()))
         }
     }
 
     nonisolated func request(_ request: OSSystemExtensionRequest, didFailWithError error: Error) {
-        Task { @MainActor in finishRequest(.failure(error)) }
+        Task { @MainActor in finishRequest(request, .failure(error)) }
     }
 }
 

macos/build.sh

@@ -1,5 +1,5 @@
 #!/bin/bash
-# Builds and signs StrixFirewall.app, installs it to /Applications, and packages it as build/Firewall.pkg.
+# Builds and signs StrixFirewall.app and packages it as build/Firewall.pkg.
 # The package is notarized with the notarytool keychain profile in NOTARY_PROFILE; `build.sh debug`
 # makes a Debug build and skips notarization.
 #
@@ -39,7 +39,6 @@ PKG_ROOT=build/pkg-root
 main() {
   build
   sign
-  install_app
   package
   [ $CONFIGURATION = Debug ] || notarize
 }
@@ -64,13 +63,6 @@ sign() {
   codesign --verify --deep --strict "$APP"
 }
 
-# The extension can only be activated from /Applications.
-install_app() {
-  echo "==> Installing /Applications/StrixFirewall.app"
-  rm -rf /Applications/StrixFirewall.app
-  cp -R "$APP" /Applications/StrixFirewall.app
-}
-
 # Marked non-relocatable so the installer never updates another copy with the same bundle id.
 package() {
   echo "==> Packaging build/Firewall.pkg"

macos/project.yml

@@ -97,6 +97,7 @@ targets:
     settings:
       base:
         PRODUCT_BUNDLE_IDENTIFIER: com.usestrix.firewall
+        ASSETCATALOG_COMPILER_APPICON_NAME: AppIcon
     info:
       path: App/Info.plist
       properties: