Make tab capture media stream requests verify that the request came from extension API

chrome/browser/media/media_stream_devices_controller.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/media/media_stream_devices_controller.h"
 
 #include "base/values.h"
 #include "chrome/browser/content_settings/content_settings_provider.h"
 #include "chrome/browser/content_settings/host_content_settings_map.h"
+#include "chrome/browser/extensions/api/tab_capture/tab_capture_registry.h"
+#include "chrome/browser/extensions/api/tab_capture/tab_capture_registry_factory.h"
 #include "chrome/browser/prefs/scoped_user_pref_update.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/common/content_settings.h"
 #include "chrome/common/pref_names.h"
 #include "content/public/common/media_stream_request.h"
 
 using content::BrowserThread;
 
 namespace {
@@ skipping 35 matching lines @@
       has_audio_ |= !it->second.empty();
     } else if (content::IsVideoMediaType(it->first)) {
       has_video_ |= !it->second.empty();
     }
   }
 }
 
 MediaStreamDevicesController::~MediaStreamDevicesController() {}
 
 bool MediaStreamDevicesController::DismissInfoBarAndTakeActionOnSettings() {
+  // For tab media requests, we need to make sure the request came from the
+  // extension API, so we check the registry here.
+  content::MediaStreamDeviceMap::const_iterator tab_video =
+      request_.devices.find(content::MEDIA_TAB_VIDEO_CAPTURE);
+  content::MediaStreamDeviceMap::const_iterator tab_audio =
+      request_.devices.find(content::MEDIA_TAB_VIDEO_CAPTURE);

[wjia(left Chromium), 2012/10/18 04:54:27]

MEDIA_TAB_AUDIO_CAPTURE?

[justinlin, 2012/10/18 07:05:47]

Done. Thanks.

+  if (tab_video != request_.devices.end() ||
+      tab_audio != request_.devices.end()) {
+    extensions::TabCaptureRegistry* registry =
+        extensions::TabCaptureRegistryFactory::GetForProfile(profile_);
+
+    DCHECK(tab_audio->second.size() || tab_video->second.size());
+    std::string audio_device_id;
+    std::string video_device_id;
+
+    if (tab_audio->second.size())
+      audio_device_id = tab_audio->second[0].device_id;
+    if (tab_video->second.size())
+      video_device_id = tab_video->second[0].device_id;
+
+    if (!registry->VerifyRequest(!video_device_id.empty() ?
+                                 video_device_id : audio_device_id))
+      Deny();
+    else
+      Accept(audio_device_id, video_device_id,
+             false);

[wjia(left Chromium), 2012/10/18 04:54:27]

nit: this fits in one line.

[justinlin, 2012/10/18 07:05:47]

Done.

+
+    return true;

[wjia(left Chromium), 2012/10/18 04:54:27]

It seems always returning true. Do you really need this return type?

[justinlin, 2012/10/18 07:05:47]

There seems to be 1 case below where it returns false.

+  }
+
   // Deny the request if the security origin is empty, this happens with
   // file access without |--allow-file-access-from-files| flag.
   if (request_.security_origin.is_empty()) {
     Deny();
     return true;
   }
 
   // Deny the request and don't show the infobar if there is no devices.
   if (!has_audio_ && !has_video_) {
     // TODO(xians): We should detect this in a early state, and post a callback
@@ skipping 246 matching lines @@
     for (content::MediaStreamDevices::const_iterator device_it =
              it->second.begin();
          device_it != it->second.end(); ++device_it) {
       const content::MediaStreamDevice& candidate = *device_it;
       if (candidate.device_id == device_id)
         return &candidate;
     }
   }
   return NULL;
 }