Add 'web_accessible_resource" keyword for version 2 extension manifests. This makes extension res...

chrome/renderer/extensions/extension_resource_request_policy.cc

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/renderer/extensions/extension_resource_request_policy.h"
 
+#include "base/command_line.h"
 #include "base/logging.h"
+#include "chrome/common/chrome_switches.h"
 #include "chrome/common/url_constants.h"
 #include "chrome/common/extensions/extension.h"
 #include "chrome/common/extensions/extension_set.h"
 #include "googleurl/src/gurl.h"
 
 // static
 bool ExtensionResourceRequestPolicy::CanRequestResource(
     const GURL& resource_url,
     const GURL& frame_url,
     const ExtensionSet* loaded_extensions) {
@@ skipping 13 matching lines @@
   // launchers.
   std::string resource_root_relative_path =
       resource_url.path().empty() ? "" : resource_url.path().substr(1);
   if (extension->is_hosted_app() &&
       !extension->icons().ContainsPath(resource_root_relative_path)) {
     LOG(ERROR) << "Denying load of " << resource_url.spec() << " from "
                << "hosted app.";
     return false;
   }
 
+  // Disallow loading of extension resources which are not explicitely listed
+  // as web accessible if the manifest version is 2 or greater.
+
+  // Exceptions are:
+  // - empty origin (needed for some edge cases when we have empty origins)
+  // - chrome-extension:// (for legacy reasons -- some extensions interop)
+  if (!CommandLine::ForCurrentProcess()->HasSwitch(
+          switches::kDisableExtensionsResourceWhitelist) &&
+      !frame_url.is_empty() &&
+      !frame_url.SchemeIs(chrome::kExtensionScheme) &&
+      !extension->IsResourceWebAccessible(resource_url.path())) {
+    LOG(ERROR) << "Denying load of " << resource_url.spec() << " which "
+               << "is not a web accessible resource.";
+    return false;
+  }
+
   return true;
 }
 
 ExtensionResourceRequestPolicy::ExtensionResourceRequestPolicy() {
 }