From 6cd518bee91151029c6e524f5b75714da17e54fa Mon Sep 17 00:00:00 2001
From: Valentin Gosu <valentin.gosu@gmail.com>
Date: Thu, 30 Sep 2021 11:58:52 +0000
Subject: [PATCH] Bug 1732961 - TRR should not be ignoring enterprise policy
 value of network.trr.uri/mode r=nhnt11

In bug 1626057 we added support for steering. There we made the distinction
between a default network.trr.uri pref, and a user-set one by using
`Preferences::HasUserValue`. However, it seems that enterprise policies change
the default branch of the pref, so this would lead to it having a lower
priority than DoHRollout or steering.

In bug 1713036 we introduced `network.trr.default_provider_uri` and made
`network.trr.uri` an empty string, so checking hasUserValue isn't required
anymore.

Differential Revision: https://phabricator.services.mozilla.com/D126961
---
 netwerk/dns/TRRService.cpp       | 4 ++--
 netwerk/dns/TRRServiceBase.cpp   | 3 +--
 netwerk/dns/TRRServiceBase.h     | 1 -
 netwerk/dns/TRRServiceParent.cpp | 8 ++++----
 4 files changed, 7 insertions(+), 9 deletions(-)

diff --git a/netwerk/dns/TRRService.cpp b/netwerk/dns/TRRService.cpp
index b58867dde7fb..5960037afc68 100644
--- a/netwerk/dns/TRRService.cpp
+++ b/netwerk/dns/TRRService.cpp
@@ -231,9 +231,9 @@ bool TRRService::GetParentalControlEnabledInternal() {
 void TRRService::SetDetectedTrrURI(const nsACString& aURI) {
   LOG(("SetDetectedTrrURI(%s", nsPromiseFlatCString(aURI).get()));
   // If the user has set a custom URI then we don't want to override that.
-  // If the URI is set via doh-rollout.uri, mURIPrefHasUserValue will be false
+  // If the URI is set via doh-rollout.uri, mURIPref will be empty
   // (see TRRServiceBase::OnTRRURIChange)
-  if (mURIPrefHasUserValue) {
+  if (!mURIPref.IsEmpty()) {
     LOG(("Already has user value. Not setting URI"));
     return;
   }
diff --git a/netwerk/dns/TRRServiceBase.cpp b/netwerk/dns/TRRServiceBase.cpp
index 3320f8b9a4e0..571f393b242c 100644
--- a/netwerk/dns/TRRServiceBase.cpp
+++ b/netwerk/dns/TRRServiceBase.cpp
@@ -74,7 +74,7 @@ void TRRServiceBase::CheckURIPrefs() {
   mURISetByDetection = false;
 
   // The user has set a custom URI so it takes precedence.
-  if (mURIPrefHasUserValue) {
+  if (!mURIPref.IsEmpty()) {
     MaybeSetPrivateURI(mURIPref);
     return;
   }
@@ -142,7 +142,6 @@ void TRRServiceBase::OnTRRModeChange() {
 }
 
 void TRRServiceBase::OnTRRURIChange() {
-  mURIPrefHasUserValue = Preferences::HasUserValue("network.trr.uri");
   Preferences::GetCString("network.trr.uri", mURIPref);
   Preferences::GetCString(kRolloutURIPref, mRolloutURIPref);
   Preferences::GetCString("network.trr.default_provider_uri", mDefaultURIPref);
diff --git a/netwerk/dns/TRRServiceBase.h b/netwerk/dns/TRRServiceBase.h
index 4ca143231055..ae4331f0834a 100644
--- a/netwerk/dns/TRRServiceBase.h
+++ b/netwerk/dns/TRRServiceBase.h
@@ -41,7 +41,6 @@ class TRRServiceBase {
 
   nsCString mPrivateURI;
   // Pref caches should only be used on the main thread.
-  bool mURIPrefHasUserValue = false;
   nsCString mURIPref;
   nsCString mRolloutURIPref;
   nsCString mDefaultURIPref;
diff --git a/netwerk/dns/TRRServiceParent.cpp b/netwerk/dns/TRRServiceParent.cpp
index d40ba0d5d496..e7dc63ef77f0 100644
--- a/netwerk/dns/TRRServiceParent.cpp
+++ b/netwerk/dns/TRRServiceParent.cpp
@@ -106,15 +106,15 @@ bool TRRServiceParent::MaybeSetPrivateURI(const nsACString& aURI) {
 }
 
 void TRRServiceParent::SetDetectedTrrURI(const nsACString& aURI) {
-  if (mURIPrefHasUserValue) {
+  if (!mURIPref.IsEmpty()) {
     return;
   }
 
   mURISetByDetection = MaybeSetPrivateURI(aURI);
-  RefPtr<TRRServiceParent> self = this;
-  nsCString uri(aURI);
   gIOService->CallOrWaitForSocketProcess(
-      [self, uri]() { Unused << self->SendSetDetectedTrrURI(uri); });
+      [self = RefPtr{this}, uri = nsAutoCString(aURI)]() {
+        Unused << self->SendSetDetectedTrrURI(uri);
+      });
 }
 
 void TRRServiceParent::GetTrrURI(nsACString& aURI) { aURI = mPrivateURI; }