Bug 1141814 - Part2: Lower the priority of channel loading tracking resource, r=honzab

--HG--
extra : rebase_source : 8b79d23c4d2f8a813a9e76816bd540dd91bc6f8e

netwerk/base/nsBaseChannel.cpp

@@ -312,9 +312,9 @@ nsBaseChannel::ClassifyURI()
   }
 
   if (mLoadFlags & LOAD_CLASSIFY_URI) {
-    RefPtr<nsChannelClassifier> classifier = new nsChannelClassifier();
+    RefPtr<nsChannelClassifier> classifier = new nsChannelClassifier(this);
     if (classifier) {
-      classifier->Start(this);
+      classifier->Start();
     } else {
       Cancel(NS_ERROR_OUT_OF_MEMORY);
     }

netwerk/base/nsChannelClassifier.cpp

@@ -25,6 +25,7 @@
 #include "nsIScriptSecurityManager.h"
 #include "nsISecureBrowserUI.h"
 #include "nsISecurityEventSink.h"
+#include "nsISupportsPriority.h"
 #include "nsIURL.h"
 #include "nsIWebProgressListener.h"
 #include "nsNetUtil.h"
@@ -50,14 +51,25 @@ static LazyLogModule gChannelClassifierLog("nsChannelClassifier");
 NS_IMPL_ISUPPORTS(nsChannelClassifier,
                   nsIURIClassifierCallback)
 
-nsChannelClassifier::nsChannelClassifier()
+nsChannelClassifier::nsChannelClassifier(nsIChannel *aChannel)
   : mIsAllowListed(false),
-    mSuspendedChannel(false)
+    mSuspendedChannel(false),
+    mChannel(aChannel),
+    mTrackingProtectionEnabled(Nothing())
 {
+  MOZ_ASSERT(mChannel);
 }
 
 nsresult
-nsChannelClassifier::ShouldEnableTrackingProtection(nsIChannel *aChannel,
+nsChannelClassifier::ShouldEnableTrackingProtection(bool *result)
+{
+  nsresult rv = ShouldEnableTrackingProtectionInternal(mChannel, result);
+  mTrackingProtectionEnabled = Some(*result);
+  return rv;
+}
+
+nsresult
+nsChannelClassifier::ShouldEnableTrackingProtectionInternal(nsIChannel *aChannel,
                                                             bool *result)
 {
     // Should only be called in the parent process.
@@ -252,10 +264,8 @@ nsChannelClassifier::NotifyTrackingProtectionDisabled(nsIChannel *aChannel)
 }
 
 void
-nsChannelClassifier::Start(nsIChannel *aChannel)
+nsChannelClassifier::Start()
 {
-  mChannel = aChannel;
-
   nsresult rv = StartInternal();
   if (NS_FAILED(rv)) {
     // If we aren't getting a callback for any reason, assume a good verdict and
@@ -344,7 +354,19 @@ nsChannelClassifier::StartInternal()
 
     bool expectCallback;
     bool trackingProtectionEnabled = false;
-    (void)ShouldEnableTrackingProtection(mChannel, &trackingProtectionEnabled);
+    if (mTrackingProtectionEnabled.isNothing()) {
+      (void)ShouldEnableTrackingProtection(&trackingProtectionEnabled);
+    } else {
+      trackingProtectionEnabled = mTrackingProtectionEnabled.value();
+    }
+
+    static bool sAnnotateChannelEnabled = false;
+    static bool sIsInited = false;
+    if (!sIsInited) {
+      sIsInited = true;
+      Preferences::AddBoolVarCache(&sAnnotateChannelEnabled,
+                                   "privacy.trackingprotection.annotate_channels");
+    }
 
     if (LOG_ENABLED()) {
       nsCOMPtr<nsIURI> principalURI;
@@ -353,8 +375,8 @@ nsChannelClassifier::StartInternal()
            "uri %s", this, principalURI->GetSpecOrDefault().get(),
            uri->GetSpecOrDefault().get()));
     }
-    rv = uriClassifier->Classify(principal, trackingProtectionEnabled, this,
+    rv = uriClassifier->Classify(principal, sAnnotateChannelEnabled | trackingProtectionEnabled,
-                                 &expectCallback);
+                                 this, &expectCallback);
     if (NS_FAILED(rv)) {
         return rv;
     }
@@ -667,6 +689,26 @@ nsChannelClassifier::OnClassifyComplete(nsresult aErrorCode)
       }
       MarkEntryClassified(aErrorCode);
 
+      // The value of |mTrackingProtectionEnabled| should be assigned at
+      // |ShouldEnableTrackingProtection| before.
+      MOZ_ASSERT(mTrackingProtectionEnabled, "Should contain a value.");
+
+      if (aErrorCode == NS_ERROR_TRACKING_URI &&
+          !mTrackingProtectionEnabled.valueOr(false)) {
+        if (LOG_ENABLED()) {
+          nsCOMPtr<nsIURI> uri;
+          mChannel->GetURI(getter_AddRefs(uri));
+          LOG(("nsChannelClassifier[%p]: lower the priority of channel %p"
+               ", since %s is a tracker", this, mChannel.get(),
+               uri->GetSpecOrDefault().get()));
+        }
+        nsCOMPtr<nsISupportsPriority> p = do_QueryInterface(mChannel);
+        if (p) {
+          p->SetPriority(nsISupportsPriority::PRIORITY_LOWEST);
+        }
+        aErrorCode = NS_OK;
+      }
+
       if (NS_FAILED(aErrorCode)) {
         if (LOG_ENABLED()) {
           nsCOMPtr<nsIURI> uri;

netwerk/base/nsChannelClassifier.h

@@ -8,6 +8,7 @@
 #include "nsIURIClassifier.h"
 #include "nsCOMPtr.h"
 #include "mozilla/Attributes.h"
+#include "mozilla/Maybe.h"
 
 class nsIChannel;
 class nsIHttpChannelInternal;
@@ -19,16 +20,16 @@ namespace net {
 class nsChannelClassifier final : public nsIURIClassifierCallback
 {
 public:
-    nsChannelClassifier();
+    explicit nsChannelClassifier(nsIChannel* aChannel);
 
     NS_DECL_ISUPPORTS
     NS_DECL_NSIURICLASSIFIERCALLBACK
 
     // Calls nsIURIClassifier.Classify with the principal of the given channel,
     // and cancels the channel on a bad verdict.
-    void Start(nsIChannel *aChannel);
+    void Start();
     // Whether or not tracking protection should be enabled on this channel.
-    nsresult ShouldEnableTrackingProtection(nsIChannel *aChannel, bool *result);
+    nsresult ShouldEnableTrackingProtection(bool *result);
 
 private:
     // True if the channel is on the allow list.
@@ -36,6 +37,7 @@ private:
     // True if the channel has been suspended.
     bool mSuspendedChannel;
     nsCOMPtr<nsIChannel> mChannel;
+    Maybe<bool> mTrackingProtectionEnabled;
 
     ~nsChannelClassifier() {}
     // Caches good classifications for the channel principal.
@@ -52,6 +54,9 @@ private:
     // Checks that the channel was loaded by the URI currently loaded in aDoc
     static bool SameLoadingURI(nsIDocument *aDoc, nsIChannel *aChannel);
 
+    nsresult ShouldEnableTrackingProtectionInternal(nsIChannel *aChannel,
+                                                    bool *result);
+
 public:
     // If we are blocking tracking content, update the corresponding flag in
     // the respective docshell and call nsISecurityEventSink::onSecurityChange.

netwerk/protocol/http/nsHttpChannel.cpp

@@ -5885,12 +5885,14 @@ nsHttpChannel::BeginConnect()
         return AsyncCall(&nsHttpChannel::HandleAsyncAPIRedirect);
     }
     // Check to see if this principal exists on local blocklists.
-    RefPtr<nsChannelClassifier> channelClassifier = new nsChannelClassifier();
+    RefPtr<nsChannelClassifier> channelClassifier = new nsChannelClassifier(this);
     if (mLoadFlags & LOAD_CLASSIFY_URI) {
         nsCOMPtr<nsIURIClassifier> classifier = do_GetService(NS_URICLASSIFIERSERVICE_CONTRACTID);
         bool tpEnabled = false;
-        channelClassifier->ShouldEnableTrackingProtection(this, &tpEnabled);
+        channelClassifier->ShouldEnableTrackingProtection(&tpEnabled);
-        if (classifier && tpEnabled) {
+        bool annotateChannelEnabled =
+            Preferences::GetBool("privacy.trackingprotection.annotate_channels");
+        if (classifier && (tpEnabled || annotateChannelEnabled)) {
             // We skip speculative connections by setting mLocalBlocklist only
             // when tracking protection is enabled. Though we could do this for
             // both phishing and malware, it is not necessary for correctness,
@@ -6012,7 +6014,7 @@ nsHttpChannel::BeginConnect()
     // be overridden.
     LOG(("nsHttpChannel::Starting nsChannelClassifier %p [this=%p]",
          channelClassifier.get(), this));
-    channelClassifier->Start(this);
+    channelClassifier->Start();
     if (callContinueBeginConnect) {
         return ContinueBeginConnectWithResult();
     }