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

chrome/browser/media/media_stream_devices_controller.cc

Index: chrome/browser/media/media_stream_devices_controller.cc
diff --git a/chrome/browser/media/media_stream_devices_controller.cc b/chrome/browser/media/media_stream_devices_controller.cc
index 5e793bb0a08741a2d5f77497c7b4dd1d764285d8..a7bdc91fc6f46adc848b403ab6abc7e0de3ff01e 100644
--- a/chrome/browser/media/media_stream_devices_controller.cc
+++ b/chrome/browser/media/media_stream_devices_controller.cc
@@ -7,6 +7,8 @@
 #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"
@@ -62,6 +64,35 @@ MediaStreamDevicesController::MediaStreamDevicesController(
 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_AUDIO_CAPTURE);
+  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());

[no longer working on chromium, 2012/10/18 08:36:17]

use !tab_audio->second.empty(), the same for other places.

[justinlin, 2012/10/18 09:33:29]

Done.

+    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))

[no longer working on chromium, 2012/10/18 08:36:17]

Does it mean that we will have either video_device_id or audio_device_id, and
never both?

[no longer working on chromium, 2012/10/18 08:36:17]

add a { because "if" takes two line.

[justinlin, 2012/10/18 09:33:29]

Done.

[justinlin, 2012/10/18 09:33:29]

No, this is a little bit related to http://crbug.com/155444. The issue is that
DeviceRequest only has one requested_device_id, so we key the registry (where
extensions keep track of the media stream requests for tabs) by a single
device_id. If video is request, then we use that one, if not we use the one from
audio, but they will both be the same anyway. I think there's checks before this
that prevent us from getting here without a tab video device right now, but if
later we allowed only capturing tab audio, then we might not have a tab video
device here.

+      Deny();
+    else
+      Accept(audio_device_id, video_device_id, false);
+
+    return true;
+  }
+
   // 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()) {