desktop_streams_registry.cc revision a1401311d1ab56c4ed0a474bd38c108f75cb0cd9 
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
13namespace {
14
15const int kStreamIdLengthBytes = 16;
16
17const int kApprovedStreamTimeToLiveSeconds = 10;
18
19std::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
30DesktopStreamsRegistry::DesktopStreamsRegistry() {}
31DesktopStreamsRegistry::~DesktopStreamsRegistry() {}
32
33std::string DesktopStreamsRegistry::RegisterStream(
34    int render_process_id,
35    int render_view_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  ApprovedDesktopMediaStream& stream = approved_streams_[id];
43  stream.render_process_id = render_process_id;
44  stream.render_view_id = render_view_id;
45  stream.origin = origin;
46  stream.source = source;
47  stream.extension_name = extension_name;
48
49  content::BrowserThread::PostDelayedTask(
50      content::BrowserThread::UI, FROM_HERE,
51      base::Bind(&DesktopStreamsRegistry::CleanupStream,
52                 base::Unretained(this), id),
53      base::TimeDelta::FromSeconds(kApprovedStreamTimeToLiveSeconds));
54
55  return id;
56}
57
58content::DesktopMediaID DesktopStreamsRegistry::RequestMediaForStreamId(
59    const std::string& id,
60    int render_process_id,
61    int render_view_id,
62    const GURL& origin,
63    std::string* extension_name) {
64  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
65
66  StreamsMap::iterator it = approved_streams_.find(id);
67
68  // Verify that if there is a request with the specified ID it was created for
69  // the same origin and the same renderer.
70  if (it == approved_streams_.end() ||
71      render_process_id != it->second.render_process_id ||
72      render_view_id != it->second.render_view_id ||
73      origin != it->second.origin) {
74    return content::DesktopMediaID();
75  }
76
77  content::DesktopMediaID result = it->second.source;
78  *extension_name = it->second.extension_name;
79  approved_streams_.erase(it);
80  return result;
81}
82
83void DesktopStreamsRegistry::CleanupStream(const std::string& id) {
84  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
85  approved_streams_.erase(id);
86}
87
88DesktopStreamsRegistry::ApprovedDesktopMediaStream::ApprovedDesktopMediaStream()
89    : render_process_id(-1), render_view_id(-1) {}
90