Bug 1907304 - Check forceOffline BC flag _after_ opening the cache r=necko-reviewers,sekim,kershaw,jdescottes

Differential Revision: https://phabricator.services.mozilla.com/D219292

netwerk/protocol/http/nsHttpChannel.cpp

@@ -667,7 +667,10 @@ nsresult nsHttpChannel::OnBeforeConnect() {
 
   RefPtr<mozilla::dom::BrowsingContext> bc;
   mLoadInfo->GetBrowsingContext(getter_AddRefs(bc));
-  if (bc && bc->Top()->GetForceOffline()) {
+  // If bypassing the cache and we're forced offline
+  // we can just return the error here.
+  if (bc && bc->Top()->GetForceOffline() &&
+      BYPASS_LOCAL_CACHE(mLoadFlags, LoadPreferCacheLoadOverBypass())) {
     return NS_ERROR_OFFLINE;
   }
 
@@ -773,7 +776,12 @@ nsresult nsHttpChannel::MaybeUseHTTPSRRForUpgrade(bool aShouldUpgrade,
     return aStatus;
   }
 
-  if (mURI->SchemeIs("https") || aShouldUpgrade || !LoadUseHTTPSSVC()) {
+  RefPtr<mozilla::dom::BrowsingContext> bc;
+  mLoadInfo->GetBrowsingContext(getter_AddRefs(bc));
+  bool forceOffline = bc && bc->Top()->GetForceOffline();
+
+  if (mURI->SchemeIs("https") || aShouldUpgrade || !LoadUseHTTPSSVC() ||
+      forceOffline) {
     return ContinueOnBeforeConnect(aShouldUpgrade, aStatus);
   }
 
@@ -1190,10 +1198,19 @@ nsresult nsHttpChannel::ContinueConnect() {
                      "CORS preflight must have been finished by the time we "
                      "do the rest of ContinueConnect");
 
+  RefPtr<mozilla::dom::BrowsingContext> bc;
+  mLoadInfo->GetBrowsingContext(getter_AddRefs(bc));
+
   // we may or may not have a cache entry at this point
   if (mCacheEntry) {
     // read straight from the cache if possible...
     if (mCachedContentIsValid) {
+      // If we're forced offline, and set to bypass the cache, return offline.
+      if (bc && bc->Top()->GetForceOffline() &&
+          BYPASS_LOCAL_CACHE(mLoadFlags, LoadPreferCacheLoadOverBypass())) {
+        return NS_ERROR_OFFLINE;
+      }
+
       nsRunnableMethod<nsHttpChannel>* event = nullptr;
       nsresult rv;
       if (!LoadCachedContentIsPartial()) {
@@ -1230,6 +1247,11 @@ nsresult nsHttpChannel::ContinueConnect() {
     return NS_ERROR_DOCUMENT_NOT_CACHED;
   }
 
+  // We're about to hit the network. Don't if we're forced offline.
+  if (bc && bc->Top()->GetForceOffline()) {
+    return NS_ERROR_OFFLINE;
+  }
+
   // hit the net...
   nsresult rv = DoConnect(mTransactionSticky);
   mTransactionSticky = nullptr;
@@ -4138,10 +4160,10 @@ nsresult nsHttpChannel::OpenCacheEntryInternal(bool isHttps) {
     return NS_OK;
   }
 
-  if (offline || (mLoadFlags & INHIBIT_CACHING) ||
-      (bc && bc->Top()->GetForceOffline())) {
+  bool forceOffline = bc && bc->Top()->GetForceOffline();
+  if (offline || (mLoadFlags & INHIBIT_CACHING) || forceOffline) {
     if (BYPASS_LOCAL_CACHE(mLoadFlags, LoadPreferCacheLoadOverBypass()) &&
-        !offline) {
+        !offline && !forceOffline) {
       return NS_OK;
     }
     cacheEntryOpenFlags = nsICacheStorage::OPEN_READONLY;