1 // Copyright 2013 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 #include "chrome/browser/media/desktop_streams_registry.h"
6
7 #include "base/base64.h"
8 #include "base/location.h"
9 #include "base/time/time.h"
10 #include "content/public/browser/browser_thread.h"
11 #include "crypto/random.h"
12
13 namespace {
14
15 const int kStreamIdLengthBytes = 16;
16
17 const int kApprovedStreamTimeToLiveSeconds = 10;
18
GenerateRandomStreamId()19 std::string GenerateRandomStreamId() {
20 char buffer[kStreamIdLengthBytes];
21 crypto::RandBytes(buffer, arraysize(buffer));
22 std::string result;
23 base::Base64Encode(base::StringPiece(buffer, arraysize(buffer)),
24 &result);
25 return result;
26 }
27
28 } // namespace
29
DesktopStreamsRegistry()30 DesktopStreamsRegistry::DesktopStreamsRegistry() {}
~DesktopStreamsRegistry()31 DesktopStreamsRegistry::~DesktopStreamsRegistry() {}
32
RegisterStream(int render_process_id,int render_frame_id,const GURL & origin,const content::DesktopMediaID & source,const std::string & extension_name)33 std::string DesktopStreamsRegistry::RegisterStream(
34 int render_process_id,
35 int render_frame_id,
36 const GURL& origin,
37 const content::DesktopMediaID& source,
38 const std::string& extension_name) {
39 DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
40
41 std::string id = GenerateRandomStreamId();
42 DCHECK(approved_streams_.find(id) == approved_streams_.end());
43 ApprovedDesktopMediaStream& stream = approved_streams_[id];
44 stream.render_process_id = render_process_id;
45 stream.render_frame_id = render_frame_id;
46 stream.origin = origin;
47 stream.source = source;
48 stream.extension_name = extension_name;
49
50 content::BrowserThread::PostDelayedTask(
51 content::BrowserThread::UI, FROM_HERE,
52 base::Bind(&DesktopStreamsRegistry::CleanupStream,
53 base::Unretained(this), id),
54 base::TimeDelta::FromSeconds(kApprovedStreamTimeToLiveSeconds));
55
56 return id;
57 }
58
RequestMediaForStreamId(const std::string & id,int render_process_id,int render_frame_id,const GURL & origin,std::string * extension_name)59 content::DesktopMediaID DesktopStreamsRegistry::RequestMediaForStreamId(
60 const std::string& id,
61 int render_process_id,
62 int render_frame_id,
63 const GURL& origin,
64 std::string* extension_name) {
65 DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
66
67 StreamsMap::iterator it = approved_streams_.find(id);
68
69 // Verify that if there is a request with the specified ID it was created for
70 // the same origin and the same renderer.
71 if (it == approved_streams_.end() ||
72 render_process_id != it->second.render_process_id ||
73 render_frame_id != it->second.render_frame_id ||
74 origin != it->second.origin) {
75 return content::DesktopMediaID();
76 }
77
78 content::DesktopMediaID result = it->second.source;
79 *extension_name = it->second.extension_name;
80 approved_streams_.erase(it);
81 return result;
82 }
83
CleanupStream(const std::string & id)84 void DesktopStreamsRegistry::CleanupStream(const std::string& id) {
85 DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
86 approved_streams_.erase(id);
87 }
88
ApprovedDesktopMediaStream()89 DesktopStreamsRegistry::ApprovedDesktopMediaStream::ApprovedDesktopMediaStream()
90 : render_process_id(-1), render_frame_id(-1) {}
91