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// Copyright 2016 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/capture_access_handler_base.h"
#include <string>
#include <utility>
#include "base/strings/string_number_conversions.h"
#include "chrome/browser/media/webrtc/media_capture_devices_dispatcher.h"
#include "content/public/browser/browser_thread.h"
#include "extensions/common/extension.h"
#if defined(OS_CHROMEOS)
#include "base/sha1.h"
#endif // defined(OS_CHROMEOS)
using content::BrowserThread;
// Tracks MEDIA_DESKTOP/TAB_VIDEO_CAPTURE sessions. Sessions are removed when
// MEDIA_REQUEST_STATE_CLOSING is encountered.
struct CaptureAccessHandlerBase::Session {
int render_process_id;
int render_frame_id;
int page_request_id;
// Extensions control the routing of the captured MediaStream content.
// Therefore, only built-in extensions (and certain whitelisted ones) can be
// trusted to set-up secure links.
bool is_trusted;
// This is true only if all connected video sinks are reported secure.
bool is_capturing_link_secure;
};
CaptureAccessHandlerBase::CaptureAccessHandlerBase() {}
CaptureAccessHandlerBase::~CaptureAccessHandlerBase() {}
void CaptureAccessHandlerBase::AddCaptureSession(int render_process_id,
int render_frame_id,
int page_request_id,
bool is_trusted) {
Session session = {render_process_id, render_frame_id, page_request_id,
is_trusted, true};
sessions_.push_back(session);
}
void CaptureAccessHandlerBase::RemoveCaptureSession(int render_process_id,
int render_frame_id,
int page_request_id) {
auto it = FindSession(render_process_id, render_frame_id, page_request_id);
if (it != sessions_.end())
sessions_.erase(it);
}
std::list<CaptureAccessHandlerBase::Session>::iterator
CaptureAccessHandlerBase::FindSession(int render_process_id,
int render_frame_id,
int page_request_id) {
return std::find_if(sessions_.begin(), sessions_.end(),
[render_process_id, render_frame_id,
page_request_id](const Session& session) {
return session.render_process_id == render_process_id &&
session.render_frame_id == render_frame_id &&
session.page_request_id == page_request_id;
});
}
void CaptureAccessHandlerBase::UpdateMediaRequestState(
int render_process_id,
int render_frame_id,
int page_request_id,
blink::MediaStreamType stream_type,
content::MediaRequestState state) {
DCHECK_CURRENTLY_ON(BrowserThread::UI);
if ((stream_type != blink::MEDIA_GUM_DESKTOP_VIDEO_CAPTURE) &&
(stream_type != blink::MEDIA_GUM_TAB_VIDEO_CAPTURE) &&
(stream_type != blink::MEDIA_DISPLAY_VIDEO_CAPTURE))
return;
if (state == content::MEDIA_REQUEST_STATE_DONE) {
if (FindSession(render_process_id, render_frame_id, page_request_id) ==
sessions_.end()) {
AddCaptureSession(render_process_id, render_frame_id, page_request_id,
false);
DVLOG(2) << "Add new session while UpdateMediaRequestState"
<< " render_process_id: " << render_process_id
<< " render_frame_id: " << render_frame_id
<< " page_request_id: " << page_request_id;
}
} else if (state == content::MEDIA_REQUEST_STATE_CLOSING) {
RemoveCaptureSession(render_process_id, render_frame_id, page_request_id);
DVLOG(2) << "Remove session: "
<< " render_process_id: " << render_process_id
<< " render_frame_id: " << render_frame_id
<< " page_request_id: " << page_request_id;
}
}
void CaptureAccessHandlerBase::UpdateExtensionTrusted(
const content::MediaStreamRequest& request,
const extensions::Extension* extension) {
const bool is_trusted = MediaCaptureDevicesDispatcher::IsOriginForCasting(
request.security_origin) ||
IsExtensionWhitelistedForScreenCapture(extension) ||
IsBuiltInExtension(request.security_origin);
UpdateTrusted(request, is_trusted);
}
void CaptureAccessHandlerBase::UpdateTrusted(
const content::MediaStreamRequest& request,
bool is_trusted) {
auto it = FindSession(request.render_process_id, request.render_frame_id,
request.page_request_id);
if (it != sessions_.end()) {
it->is_trusted = is_trusted;
DVLOG(2) << "CaptureAccessHandlerBase::UpdateTrusted"
<< " render_process_id: " << request.render_process_id
<< " render_frame_id: " << request.render_frame_id
<< " page_request_id: " << request.page_request_id
<< " is_trusted: " << is_trusted;
return;
}
AddCaptureSession(request.render_process_id, request.render_frame_id,
request.page_request_id, is_trusted);
DVLOG(2) << "Add new session while UpdateTrusted"
<< " render_process_id: " << request.render_process_id
<< " render_frame_id: " << request.render_frame_id
<< " page_request_id: " << request.page_request_id
<< " is_trusted: " << is_trusted;
}
bool CaptureAccessHandlerBase::IsInsecureCapturingInProgress(
int render_process_id,
int render_frame_id) {
if (sessions_.empty())
return false;
for (const Session& session : sessions_) {
if (session.render_process_id != render_process_id ||
session.render_frame_id != render_frame_id)
continue;
if (!session.is_trusted || !session.is_capturing_link_secure)
return true;
}
return false;
}
void CaptureAccessHandlerBase::UpdateVideoScreenCaptureStatus(
int render_process_id,
int render_frame_id,
int page_request_id,
bool is_secure) {
auto it = FindSession(render_process_id, render_frame_id, page_request_id);
if (it != sessions_.end()) {
it->is_capturing_link_secure = is_secure;
DVLOG(2) << "UpdateVideoScreenCaptureStatus:"
<< " render_process_id: " << render_process_id
<< " render_frame_id: " << render_frame_id
<< " page_request_id: " << page_request_id
<< " is_capturing_link_secure: " << is_secure;
}
}
bool CaptureAccessHandlerBase::IsExtensionWhitelistedForScreenCapture(
const extensions::Extension* extension) {
if (!extension)
return false;
#if defined(OS_CHROMEOS)
std::string hash = base::SHA1HashString(extension->id());
std::string hex_hash = base::HexEncode(hash.c_str(), hash.length());
// crbug.com/446688
return hex_hash == "4F25792AF1AA7483936DE29C07806F203C7170A0" ||
hex_hash == "BD8781D757D830FC2E85470A1B6E8A718B7EE0D9" ||
hex_hash == "4AC2B6C63C6480D150DFDA13E4A5956EB1D0DDBB" ||
hex_hash == "81986D4F846CEDDDB962643FA501D1780DD441BB";
#else
return false;
#endif // defined(OS_CHROMEOS)
}
bool CaptureAccessHandlerBase::IsBuiltInExtension(const GURL& origin) {
return
// Feedback Extension.
origin.spec() == "chrome-extension://gfdkimpbcpahaombhbimeihdjnejgicl/";
}
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