chrome/browser/extensions/api/tab_capture/tab_capture_api.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 // Implements the Chrome Extensions Tab Capture API.
   6
   7 #include "chrome/browser/extensions/api/tab_capture/tab_capture_api.h"
   8
   9 #include <set>
  10 #include <string>
  11 #include <vector>
  12
  13 #include "base/command_line.h"
  14 #include "base/strings/stringprintf.h"
  15 #include "base/values.h"
  16 #include "chrome/browser/extensions/api/tab_capture/tab_capture_registry.h"
  17 #include "chrome/browser/extensions/extension_renderer_state.h"
  18 #include "chrome/browser/profiles/profile.h"
  19 #include "chrome/browser/sessions/session_tab_helper.h"
  20 #include "chrome/browser/ui/browser.h"
  21 #include "chrome/browser/ui/browser_finder.h"
  22 #include "chrome/browser/ui/tabs/tab_strip_model.h"
  23 #include "content/public/browser/render_frame_host.h"
  24 #include "content/public/browser/render_process_host.h"
  25 #include "extensions/common/features/feature.h"
  26 #include "extensions/common/features/feature_provider.h"
  27 #include "extensions/common/features/simple_feature.h"
  28 #include "extensions/common/permissions/permissions_data.h"
  29 #include "extensions/common/switches.h"
  30
  31 using extensions::api::tab_capture::MediaStreamConstraint;
  32
  33 namespace TabCapture = extensions::api::tab_capture;
  34 namespace GetCapturedTabs = TabCapture::GetCapturedTabs;
  35
  36 namespace extensions {
  37
  38 namespace {
  39
  40 const char kCapturingSameTab[] = "Cannot capture a tab with an active stream.";
  41 const char kFindingTabError[] = "Error finding tab to capture.";
  42 const char kNoAudioOrVideo[] = "Capture failed. No audio or video requested.";
  43 const char kGrantError[] =
  44     "Extension has not been invoked for the current page (see activeTab "
  45     "permission). Chrome pages cannot be captured.";
  46
  47 // Keys/values for media stream constraints.
  48 const char kMediaStreamSource[] = "chromeMediaSource";
  49 const char kMediaStreamSourceId[] = "chromeMediaSourceId";
  50 const char kMediaStreamSourceTab[] = "tab";
  51
  52 // Whitelisted extensions that do not check for a browser action grant because
  53 // they provide API's.
  54 const char* const kWhitelist[] = {
  55   "enhhojjnijigcajfphajepfemndkmdlo",  // Dev
  56   "pkedcjkdefgpdelpbcmbmeomcjbeemfm",  // Trusted Tester
  57   "fmfcbgogabcbclcofgocippekhfcmgfj",  // Staging
  58   "hfaagokkkhdbgiakmmlclaapfelnkoah",  // Canary
  59   "F155646B5D1CA545F7E1E4E20D573DFDD44C2540",  // Trusted Tester (public)
  60   "16CA7A47AAE4BE49B1E75A6B960C3875E945B264"   // Release
  61 };
  62
  63 }  // namespace
  64
  65 bool TabCaptureCaptureFunction::RunSync() {
  66   scoped_ptr<api::tab_capture::Capture::Params> params =
  67       TabCapture::Capture::Params::Create(*args_);
  68   EXTENSION_FUNCTION_VALIDATE(params.get());
  69
  70   // Figure out the active WebContents and retrieve the needed ids.
  71   Browser* target_browser = chrome::FindAnyBrowser(
  72       GetProfile(), include_incognito(), chrome::GetActiveDesktop());
  73   if (!target_browser) {
  74     error_ = kFindingTabError;
  75     return false;
  76   }
  77
  78   content::WebContents* target_contents =
  79       target_browser->tab_strip_model()->GetActiveWebContents();
  80   if (!target_contents) {
  81     error_ = kFindingTabError;
  82     return false;
  83   }
  84
  85   const std::string& extension_id = extension()->id();
  86
  87   // Make sure either we have been granted permission to capture through an
  88   // extension icon click or our extension is whitelisted.
  89   if (!extension()->permissions_data()->HasAPIPermissionForTab(
  90           SessionTabHelper::IdForTab(target_contents),
  91           APIPermission::kTabCaptureForTab) &&
  92       base::CommandLine::ForCurrentProcess()->GetSwitchValueASCII(
  93           switches::kWhitelistedExtensionID) != extension_id &&
  94       !SimpleFeature::IsIdInArray(
  95           extension_id, kWhitelist, arraysize(kWhitelist))) {
  96     error_ = kGrantError;
  97     return false;
  98   }
  99
 100   // Create a constraints vector. We will modify all the constraints in this
 101   // vector to append our chrome specific constraints.
 102   std::vector<MediaStreamConstraint*> constraints;
 103   bool has_audio = params->options.audio.get() && *params->options.audio.get();
 104   bool has_video = params->options.video.get() && *params->options.video.get();
 105
 106   if (!has_audio && !has_video) {
 107     error_ = kNoAudioOrVideo;
 108     return false;
 109   }
 110
 111   if (has_audio) {
 112     if (!params->options.audio_constraints.get())
 113       params->options.audio_constraints.reset(new MediaStreamConstraint);
 114
 115     constraints.push_back(params->options.audio_constraints.get());
 116   }
 117   if (has_video) {
 118     if (!params->options.video_constraints.get())
 119       params->options.video_constraints.reset(new MediaStreamConstraint);
 120
 121     constraints.push_back(params->options.video_constraints.get());
 122   }
 123
 124   // Device id we use for Tab Capture.
 125   content::RenderFrameHost* const main_frame = target_contents->GetMainFrame();
 126   // TODO(miu): We should instead use a "randomly generated device ID" scheme,
 127   // like that employed by the desktop capture API.  http://crbug.com/163100
 128   const std::string device_id = base::StringPrintf(
 129       "web-contents-media-stream://%i:%i",
 130       main_frame->GetProcess()->GetID(),
 131       main_frame->GetRoutingID());
 132
 133   // Append chrome specific tab constraints.
 134   for (std::vector<MediaStreamConstraint*>::iterator it = constraints.begin();
 135        it != constraints.end(); ++it) {
 136     base::DictionaryValue* constraint = &(*it)->mandatory.additional_properties;
 137     constraint->SetString(kMediaStreamSource, kMediaStreamSourceTab);
 138     constraint->SetString(kMediaStreamSourceId, device_id);
 139   }
 140
 141   TabCaptureRegistry* registry = TabCaptureRegistry::Get(GetProfile());
 142   if (!registry->AddRequest(target_contents, extension_id)) {
 143     error_ = kCapturingSameTab;
 144     return false;
 145   }
 146
 147   // Copy the result from our modified input parameters. This will be
 148   // intercepted by custom bindings which will build and send the special
 149   // WebRTC user media request.
 150   base::DictionaryValue* result = new base::DictionaryValue();
 151   result->MergeDictionary(params->options.ToValue().get());
 152
 153   SetResult(result);
 154   return true;
 155 }
 156
 157 bool TabCaptureGetCapturedTabsFunction::RunSync() {
 158   TabCaptureRegistry* registry = TabCaptureRegistry::Get(GetProfile());
 159   base::ListValue* const list = new base::ListValue();
 160   if (registry)
 161     registry->GetCapturedTabs(extension()->id(), list);
 162   SetResult(list);
 163   return true;
 164 }
 165
 166 }  // namespace extensions