Ensure streams aren't intercepted unless their associated plugin is enabled

chrome/browser/renderer_host/chrome_resource_dispatcher_host_delegate.cc

 // Copyright (c) 2012 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/browser/renderer_host/chrome_resource_dispatcher_host_delegate.h"
 
 #include <string>
 #include <vector>
 
 #include "base/base64.h"
 #include "base/guid.h"
 #include "base/logging.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/component_updater/component_updater_resource_throttle.h"
 #include "chrome/browser/download/download_request_limiter.h"
 #include "chrome/browser/download/download_resource_throttle.h"
 #include "chrome/browser/net/resource_prefetch_predictor_observer.h"
+#include "chrome/browser/plugins/plugin_prefs.h"
 #include "chrome/browser/prefetch/prefetch.h"
 #include "chrome/browser/prerender/prerender_manager.h"
 #include "chrome/browser/prerender/prerender_manager_factory.h"
 #include "chrome/browser/prerender/prerender_resource_throttle.h"
 #include "chrome/browser/prerender/prerender_tracker.h"
 #include "chrome/browser/prerender/prerender_util.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/profiles/profile_io_data.h"
 #include "chrome/browser/renderer_host/safe_browsing_resource_throttle_factory.h"
 #include "chrome/browser/safe_browsing/safe_browsing_service.h"
 #include "chrome/browser/signin/signin_header_helper.h"
 #include "chrome/browser/tab_contents/tab_util.h"
 #include "chrome/browser/ui/login/login_prompt.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/render_messages.h"
 #include "chrome/common/url_constants.h"
 #include "components/content_settings/core/browser/host_content_settings_map.h"
 #include "components/google/core/browser/google_util.h"
 #include "components/variations/net/variations_http_header_provider.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/notification_service.h"
+#include "content/public/browser/plugin_service.h"
+#include "content/public/browser/plugin_service_filter.h"
 #include "content/public/browser/render_process_host.h"
 #include "content/public/browser/render_view_host.h"
 #include "content/public/browser/resource_context.h"
 #include "content/public/browser/resource_dispatcher_host.h"
 #include "content/public/browser/resource_request_info.h"
 #include "content/public/browser/service_worker_context.h"
 #include "content/public/browser/stream_info.h"
 #include "content/public/browser/web_contents.h"
 #include "content/public/common/resource_response.h"
 #include "net/base/load_flags.h"
@@ skipping 150 matching lines @@
   Profile* profile =
       Profile::FromBrowserContext(web_contents->GetBrowserContext());
 
   StreamsPrivateAPI* streams_private = StreamsPrivateAPI::Get(profile);
   if (!streams_private)
     return;
   streams_private->ExecuteMimeTypeHandler(
       extension_id, web_contents, stream.Pass(), view_id, expected_content_size,
       embedded, render_process_id, render_frame_id);
 }
+
+// TODO(raymes): This won't return the right result if plugins haven't been
+// loaded yet. Fixing this properly really requires fixing crbug.com/443466.
+bool IsPluginEnabledForExtension(const Extension* extension,
+                                 const ResourceRequestInfo* info,
+                                 const std::string& mime_type,
+                                 const GURL& url) {
+  content::PluginService* service = content::PluginService::GetInstance();
+  std::vector<content::WebPluginInfo> plugins;
+  service->GetPluginInfoArray(url, mime_type, true, &plugins, nullptr);
+  content::PluginServiceFilter* filter = service->GetFilter();
+
+  for (auto& plugin : plugins) {
+    // Check that the plugin is running the extension.
+    if (plugin.path !=
+        base::FilePath::FromUTF8Unsafe(extension->url().spec())) {
+      continue;
+    }
+    // Check that the plugin is actually enabled.
+    if (!filter || filter->IsPluginAvailable(info->GetChildID(),
+                                             info->GetRenderFrameID(),
+                                             info->GetContext(),
+                                             url,
+                                             GURL(),
+                                             &plugin)) {
+      return true;
+    }
+  }
+  return false;
+}
 #endif  // !defined(ENABLE_EXTENSIONS)
 
 #if !defined(OS_ANDROID)
 void LaunchURL(const GURL& url, int render_process_id, int render_view_id) {
   // If there is no longer a WebContents, the request may have raced with tab
   // closing. Don't fire the external request. (It may have been a prerender.)
   content::WebContents* web_contents =
       tab_util::GetWebContentsByID(render_process_id, render_view_id);
   if (!web_contents)
     return;
@@ skipping 400 matching lines @@
          !extension_info_map->IsIncognitoEnabled(extension_id))) {
       continue;
     }
 
     MimeTypesHandler* handler = MimeTypesHandler::GetHandler(extension);
     if (handler && handler->CanHandleMIMEType(mime_type)) {
       StreamTargetInfo target_info;
       *origin = Extension::GetBaseURLFromExtensionId(extension_id);
       target_info.extension_id = extension_id;
       if (!handler->handler_url().empty()) {
+        // This is reached in the case of MimeHandlerViews. If the
+        // MimeHandlerView plugin is disabled, then we shouldn't intercept the
+        // stream.
+        if (!IsPluginEnabledForExtension(extension, info, mime_type,
+                                         request->url())) {
+          continue;
+        }
         target_info.view_id = base::GenerateGUID();
         *payload = target_info.view_id;
       }
       stream_target_info_[request] = target_info;
       return true;
     }
   }
 #endif
   return false;
 }
@@ skipping 127 matching lines @@
                                        url_request->GetTotalReceivedBytes()));
   }
 }
 
 // static
 void ChromeResourceDispatcherHostDelegate::
     SetExternalProtocolHandlerDelegateForTesting(
     ExternalProtocolHandler::Delegate* delegate) {
   g_external_protocol_handler_delegate = delegate;
 }