Bug 1591226 - Convert network.http.referer.hideOnionSource to a static pref. r=njn

Converts network.http.referer.hideOnionSource to a static pref and removes its mirror variable and varcache pref definition.

Differential Revision: https://phabricator.services.mozilla.com/D50534

--HG--
extra : moz-landing-system : lando

dom/security/ReferrerInfo.cpp

@@ -60,7 +60,6 @@ static uint32_t sDefaultTrackerRp = DEFAULT_TRACKER_RP;
 static uint32_t defaultPrivateRp = DEFAULT_PRIVATE_RP;
 static uint32_t defaultTrackerPrivateRp = DEFAULT_TRACKER_PRIVATE_RP;
 
-static bool sUserHideOnionReferrerSource = false;
 static uint32_t sUserReferrerSendingPolicy = 0;
 static uint32_t sUserXOriginSendingPolicy = 0;
 static uint32_t sUserTrimmingPolicy = 0;
@@ -73,8 +72,6 @@ static void CachePreferrenceValue() {
     return;
   }
 
-  Preferences::AddBoolVarCache(&sUserHideOnionReferrerSource,
-                               "network.http.referer.hideOnionSource");
   Preferences::AddUintVarCache(&sUserReferrerSendingPolicy,
                                "network.http.sendRefererHeader");
   Preferences::AddUintVarCache(&sReferrerHeaderLimit,
@@ -116,12 +113,6 @@ static void CachePreferrenceValue() {
   sPrefCached = true;
 }
 
-/* static */
-bool ReferrerInfo::HideOnionReferrerSource() {
-  CachePreferrenceValue();
-  return sUserHideOnionReferrerSource;
-}
-
 struct LegacyReferrerPolicyTokenMap {
   const char* mToken;
   ReferrerPolicy mPolicy;
@@ -369,7 +360,8 @@ nsresult ReferrerInfo::HandleUserXOriginSendingPolicy(nsIURI* aURI,
   }
 
   // Send an empty referrer if xorigin and leaving a .onion domain.
-  if (sUserHideOnionReferrerSource && !uriHost.Equals(referrerHost) &&
+  if (StaticPrefs::network_http_referer_hideOnionSource() &&
+      !uriHost.Equals(referrerHost) &&
       StringEndsWith(referrerHost, NS_LITERAL_CSTRING(".onion"))) {
     return NS_OK;
   }

dom/security/ReferrerInfo.h

@@ -161,12 +161,6 @@ class ReferrerInfo : public nsIReferrerInfo {
    */
   static bool ShouldResponseInheritReferrerInfo(nsIChannel* aChannel);
 
-  /*
-   * Check whether we need to hide referrer when leaving a .onion domain.
-   * Controlled by user pref: network.http.referer.hideOnionSource
-   */
-  static bool HideOnionReferrerSource();
-
   /*
    * Check whether referrer is allowed to send in secure to insecure scenario.
    */

modules/libpref/init/StaticPrefList.yaml

@@ -6415,6 +6415,13 @@
   value: false
   mirror: always
 
+# Check whether we need to hide referrer when leaving a .onion domain.
+# false=allow onion referer, true=hide onion referer (use empty referer).
+- name: network.http.referer.hideOnionSource
+  type: bool
+  value: false
+  mirror: always
+
 # Enables the predictive service.
 - name: network.predictor.enabled
   type: bool

modules/libpref/init/all.js

@@ -1347,8 +1347,6 @@ pref("network.http.referer.defaultPolicy.pbmode", 2);
 // No need to change this pref for trimming referrers from trackers since in
 // private windows we already trim all referrers to origin only.
 pref("network.http.referer.defaultPolicy.trackers.pbmode", 2);
-// false=allow onion referer, true=hide onion referer (use empty referer)
-pref("network.http.referer.hideOnionSource", false);
 // 0=full URI, 1=scheme+host+port+path, 2=scheme+host+port
 pref("network.http.referer.trimmingPolicy", 0);
 // 0=full URI, 1=scheme+host+port+path, 2=scheme+host+port

netwerk/protocol/http/nsCORSListenerProxy.cpp

@@ -44,6 +44,7 @@
 #include "mozilla/NullPrincipal.h"
 #include "nsIHttpHeaderVisitor.h"
 #include "nsQueryObject.h"
+#include "mozilla/StaticPrefs_network.h"
 #include <algorithm>
 
 using namespace mozilla;
@@ -964,7 +965,7 @@ nsresult nsCORSListenerProxy::UpdateChannel(nsIChannel* aChannel,
   NS_ENSURE_TRUE(http, NS_ERROR_FAILURE);
 
   // hide the Origin header when requesting from .onion and requesting CORS
-  if (dom::ReferrerInfo::HideOnionReferrerSource()) {
+  if (StaticPrefs::network_http_referer_hideOnionSource()) {
     nsCOMPtr<nsIURI> potentialOnionUri;  // the candidate uri in header Origin:
     rv = mOriginHeaderPrincipal->GetURI(getter_AddRefs(potentialOnionUri));
     NS_ENSURE_SUCCESS(rv, rv);

netwerk/protocol/http/nsHttpChannel.cpp

@@ -9800,7 +9800,7 @@ void nsHttpChannel::SetOriginHeader() {
       // Origin header suppressed by user setting
       return;
     }
-  } else if (dom::ReferrerInfo::HideOnionReferrerSource()) {
+  } else if (StaticPrefs::network_http_referer_hideOnionSource()) {
     nsAutoCString host;
     if (referrer && NS_SUCCEEDED(referrer->GetAsciiHost(host)) &&
         StringEndsWith(host, NS_LITERAL_CSTRING(".onion"))) {