src/google_apis/gcm/engine/connection_factory_impl.cc

   1 // Copyright (c) 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 "google_apis/gcm/engine/connection_factory_impl.h"
   6
   7 #include "base/message_loop/message_loop.h"
   8 #include "base/metrics/histogram.h"
   9 #include "base/metrics/sparse_histogram.h"
  10 #include "google_apis/gcm/engine/connection_handler_impl.h"
  11 #include "google_apis/gcm/monitoring/gcm_stats_recorder.h"
  12 #include "google_apis/gcm/protocol/mcs.pb.h"
  13 #include "net/base/load_flags.h"
  14 #include "net/base/net_errors.h"
  15 #include "net/http/http_network_session.h"
  16 #include "net/http/http_request_headers.h"
  17 #include "net/proxy/proxy_info.h"
  18 #include "net/socket/client_socket_handle.h"
  19 #include "net/socket/client_socket_pool_manager.h"
  20 #include "net/ssl/ssl_config_service.h"
  21
  22 namespace gcm {
  23
  24 namespace {
  25
  26 // The amount of time a Socket read should wait before timing out.
  27 const int kReadTimeoutMs = 30000;  // 30 seconds.
  28
  29 // If a connection is reset after succeeding within this window of time,
  30 // the previous backoff entry is restored (and the connection success is treated
  31 // as if it was transient).
  32 const int kConnectionResetWindowSecs = 10;  // 10 seconds.
  33
  34 // Decides whether the last login was within kConnectionResetWindowSecs of now
  35 // or not.
  36 bool ShouldRestorePreviousBackoff(const base::TimeTicks& login_time,
  37                                   const base::TimeTicks& now_ticks) {
  38   return !login_time.is_null() &&
  39       now_ticks - login_time <=
  40           base::TimeDelta::FromSeconds(kConnectionResetWindowSecs);
  41 }
  42
  43 }  // namespace
  44
  45 ConnectionFactoryImpl::ConnectionFactoryImpl(
  46     const std::vector<GURL>& mcs_endpoints,
  47     const net::BackoffEntry::Policy& backoff_policy,
  48     const scoped_refptr<net::HttpNetworkSession>& gcm_network_session,
  49     const scoped_refptr<net::HttpNetworkSession>& http_network_session,
  50     net::NetLog* net_log,
  51     GCMStatsRecorder* recorder)
  52   : mcs_endpoints_(mcs_endpoints),
  53     next_endpoint_(0),
  54     last_successful_endpoint_(0),
  55     backoff_policy_(backoff_policy),
  56     gcm_network_session_(gcm_network_session),
  57     http_network_session_(http_network_session),
  58     bound_net_log_(
  59         net::BoundNetLog::Make(net_log, net::NetLog::SOURCE_SOCKET)),
  60     pac_request_(NULL),
  61     connecting_(false),
  62     waiting_for_backoff_(false),
  63     waiting_for_network_online_(false),
  64     logging_in_(false),
  65     recorder_(recorder),
  66     listener_(NULL),
  67     weak_ptr_factory_(this) {
  68   DCHECK_GE(mcs_endpoints_.size(), 1U);
  69   DCHECK(!http_network_session_.get() ||
  70          (gcm_network_session_.get() != http_network_session_.get()));
  71 }
  72
  73 ConnectionFactoryImpl::~ConnectionFactoryImpl() {
  74   CloseSocket();
  75   net::NetworkChangeNotifier::RemoveNetworkChangeObserver(this);
  76   if (pac_request_) {
  77     gcm_network_session_->proxy_service()->CancelPacRequest(pac_request_);
  78     pac_request_ = NULL;
  79   }
  80 }
  81
  82 void ConnectionFactoryImpl::Initialize(
  83     const BuildLoginRequestCallback& request_builder,
  84     const ConnectionHandler::ProtoReceivedCallback& read_callback,
  85     const ConnectionHandler::ProtoSentCallback& write_callback) {
  86   DCHECK(!connection_handler_);
  87
  88   previous_backoff_ = CreateBackoffEntry(&backoff_policy_);
  89   backoff_entry_ = CreateBackoffEntry(&backoff_policy_);
  90   request_builder_ = request_builder;
  91
  92   net::NetworkChangeNotifier::AddNetworkChangeObserver(this);
  93   waiting_for_network_online_ = net::NetworkChangeNotifier::IsOffline();
  94   connection_handler_ = CreateConnectionHandler(
  95       base::TimeDelta::FromMilliseconds(kReadTimeoutMs),
  96       read_callback,
  97       write_callback,
  98       base::Bind(&ConnectionFactoryImpl::ConnectionHandlerCallback,
  99                  weak_ptr_factory_.GetWeakPtr())).Pass();
 100 }
 101
 102 ConnectionHandler* ConnectionFactoryImpl::GetConnectionHandler() const {
 103   return connection_handler_.get();
 104 }
 105
 106 void ConnectionFactoryImpl::Connect() {
 107   DCHECK(connection_handler_);
 108
 109   if (connecting_ || waiting_for_backoff_)
 110     return;  // Connection attempt already in progress or pending.
 111
 112   if (IsEndpointReachable())
 113     return;  // Already connected.
 114
 115   ConnectWithBackoff();
 116 }
 117
 118 void ConnectionFactoryImpl::ConnectWithBackoff() {
 119   // If a canary managed to connect while a backoff expiration was pending,
 120   // just cleanup the internal state.
 121   if (connecting_ || logging_in_ || IsEndpointReachable()) {
 122     waiting_for_backoff_ = false;
 123     return;
 124   }
 125
 126   if (backoff_entry_->ShouldRejectRequest()) {
 127     DVLOG(1) << "Delaying MCS endpoint connection for "
 128              << backoff_entry_->GetTimeUntilRelease().InMilliseconds()
 129              << " milliseconds.";
 130     waiting_for_backoff_ = true;
 131     recorder_->RecordConnectionDelayedDueToBackoff(
 132         backoff_entry_->GetTimeUntilRelease().InMilliseconds());
 133     base::MessageLoop::current()->PostDelayedTask(
 134         FROM_HERE,
 135         base::Bind(&ConnectionFactoryImpl::ConnectWithBackoff,
 136                    weak_ptr_factory_.GetWeakPtr()),
 137         backoff_entry_->GetTimeUntilRelease());
 138     return;
 139   }
 140
 141   DVLOG(1) << "Attempting connection to MCS endpoint.";
 142   waiting_for_backoff_ = false;
 143   ConnectImpl();
 144 }
 145
 146 bool ConnectionFactoryImpl::IsEndpointReachable() const {
 147   return connection_handler_ && connection_handler_->CanSendMessage();
 148 }
 149
 150 std::string ConnectionFactoryImpl::GetConnectionStateString() const {
 151   if (IsEndpointReachable())
 152     return "CONNECTED";
 153   if (logging_in_)
 154     return "LOGGING IN";
 155   if (connecting_)
 156     return "CONNECTING";
 157   if (waiting_for_backoff_)
 158     return "WAITING FOR BACKOFF";
 159   if (waiting_for_network_online_)
 160     return "WAITING FOR NETWORK CHANGE";
 161   return "NOT CONNECTED";
 162 }
 163
 164 void ConnectionFactoryImpl::SignalConnectionReset(
 165     ConnectionResetReason reason) {
 166   // A failure can trigger multiple resets, so no need to do anything if a
 167   // connection is already in progress.
 168   if (connecting_) {
 169     DVLOG(1) << "Connection in progress, ignoring reset.";
 170     return;
 171   }
 172
 173   if (listener_)
 174     listener_->OnDisconnected();
 175
 176   UMA_HISTOGRAM_ENUMERATION("GCM.ConnectionResetReason",
 177                             reason,
 178                             CONNECTION_RESET_COUNT);
 179   recorder_->RecordConnectionResetSignaled(reason);
 180   if (!last_login_time_.is_null()) {
 181     UMA_HISTOGRAM_CUSTOM_TIMES("GCM.ConnectionUpTime",
 182                                NowTicks() - last_login_time_,
 183                                base::TimeDelta::FromSeconds(1),
 184                                base::TimeDelta::FromHours(24),
 185                                50);
 186     // |last_login_time_| will be reset below, before attempting the new
 187     // connection.
 188   }
 189
 190   CloseSocket();
 191   DCHECK(!IsEndpointReachable());
 192
 193   // TODO(zea): if the network is offline, don't attempt to connect.
 194   // See crbug.com/396687
 195
 196   // Network changes get special treatment as they can trigger a one-off canary
 197   // request that bypasses backoff (but does nothing if a connection is in
 198   // progress). Other connection reset events can be ignored as a connection
 199   // is already awaiting backoff expiration.
 200   if (waiting_for_backoff_ && reason != NETWORK_CHANGE) {
 201     DVLOG(1) << "Backoff expiration pending, ignoring reset.";
 202     return;
 203   }
 204
 205   if (logging_in_) {
 206     // Failures prior to login completion just reuse the existing backoff entry.
 207     logging_in_ = false;
 208     backoff_entry_->InformOfRequest(false);
 209   } else if (reason == LOGIN_FAILURE ||
 210              ShouldRestorePreviousBackoff(last_login_time_, NowTicks())) {
 211     // Failures due to login, or within the reset window of a login, restore
 212     // the backoff entry that was saved off at login completion time.
 213     backoff_entry_.swap(previous_backoff_);
 214     backoff_entry_->InformOfRequest(false);
 215   } else if (reason == NETWORK_CHANGE) {
 216     ConnectImpl();  // Canary attempts bypass backoff without resetting it.
 217     return;
 218   } else {
 219     // We shouldn't be in backoff in thise case.
 220     DCHECK_EQ(0, backoff_entry_->failure_count());
 221   }
 222
 223   // At this point the last login time has been consumed or deemed irrelevant,
 224   // reset it.
 225   last_login_time_ = base::TimeTicks();
 226
 227   Connect();
 228 }
 229
 230 void ConnectionFactoryImpl::SetConnectionListener(
 231     ConnectionListener* listener) {
 232   listener_ = listener;
 233 }
 234
 235 base::TimeTicks ConnectionFactoryImpl::NextRetryAttempt() const {
 236   if (!backoff_entry_)
 237     return base::TimeTicks();
 238   return backoff_entry_->GetReleaseTime();
 239 }
 240
 241 void ConnectionFactoryImpl::OnNetworkChanged(
 242     net::NetworkChangeNotifier::ConnectionType type) {
 243   if (type == net::NetworkChangeNotifier::CONNECTION_NONE) {
 244     DVLOG(1) << "Network lost, resettion connection.";
 245     waiting_for_network_online_ = true;
 246
 247     // Will do nothing due to |waiting_for_network_online_ == true|.
 248     // TODO(zea): make the above statement actually true. See crbug.com/396687
 249     SignalConnectionReset(NETWORK_CHANGE);
 250     return;
 251   }
 252
 253   DVLOG(1) << "Connection type changed to " << type << ", reconnecting.";
 254   waiting_for_network_online_ = false;
 255   SignalConnectionReset(NETWORK_CHANGE);
 256 }
 257
 258 GURL ConnectionFactoryImpl::GetCurrentEndpoint() const {
 259   // Note that IsEndpointReachable() returns false anytime connecting_ is true,
 260   // so while connecting this always uses |next_endpoint_|.
 261   if (IsEndpointReachable())
 262     return mcs_endpoints_[last_successful_endpoint_];
 263   return mcs_endpoints_[next_endpoint_];
 264 }
 265
 266 net::IPEndPoint ConnectionFactoryImpl::GetPeerIP() {
 267   if (!socket_handle_.socket())
 268     return net::IPEndPoint();
 269
 270   net::IPEndPoint ip_endpoint;
 271   int result = socket_handle_.socket()->GetPeerAddress(&ip_endpoint);
 272   if (result != net::OK)
 273     return net::IPEndPoint();
 274
 275   return ip_endpoint;
 276 }
 277
 278 void ConnectionFactoryImpl::ConnectImpl() {
 279   DCHECK(!IsEndpointReachable());
 280   DCHECK(!socket_handle_.socket());
 281
 282   // TODO(zea): if the network is offline, don't attempt to connect.
 283   // See crbug.com/396687
 284
 285   connecting_ = true;
 286   GURL current_endpoint = GetCurrentEndpoint();
 287   recorder_->RecordConnectionInitiated(current_endpoint.host());
 288   RebuildNetworkSessionAuthCache();
 289   int status = gcm_network_session_->proxy_service()->ResolveProxy(
 290       current_endpoint,
 291       net::LOAD_NORMAL,
 292       &proxy_info_,
 293       base::Bind(&ConnectionFactoryImpl::OnProxyResolveDone,
 294                  weak_ptr_factory_.GetWeakPtr()),
 295       &pac_request_,
 296       NULL,
 297       bound_net_log_);
 298   if (status != net::ERR_IO_PENDING)
 299     OnProxyResolveDone(status);
 300 }
 301
 302 void ConnectionFactoryImpl::InitHandler() {
 303   // May be null in tests.
 304   mcs_proto::LoginRequest login_request;
 305   if (!request_builder_.is_null()) {
 306     request_builder_.Run(&login_request);
 307     DCHECK(login_request.IsInitialized());
 308   }
 309
 310   connection_handler_->Init(login_request, socket_handle_.socket());
 311 }
 312
 313 scoped_ptr<net::BackoffEntry> ConnectionFactoryImpl::CreateBackoffEntry(
 314     const net::BackoffEntry::Policy* const policy) {
 315   return scoped_ptr<net::BackoffEntry>(new net::BackoffEntry(policy));
 316 }
 317
 318 scoped_ptr<ConnectionHandler> ConnectionFactoryImpl::CreateConnectionHandler(
 319     base::TimeDelta read_timeout,
 320     const ConnectionHandler::ProtoReceivedCallback& read_callback,
 321     const ConnectionHandler::ProtoSentCallback& write_callback,
 322     const ConnectionHandler::ConnectionChangedCallback& connection_callback) {
 323   return make_scoped_ptr<ConnectionHandler>(
 324       new ConnectionHandlerImpl(read_timeout,
 325                                 read_callback,
 326                                 write_callback,
 327                                 connection_callback));
 328 }
 329
 330 base::TimeTicks ConnectionFactoryImpl::NowTicks() {
 331   return base::TimeTicks::Now();
 332 }
 333
 334 void ConnectionFactoryImpl::OnConnectDone(int result) {
 335   if (result != net::OK) {
 336     // If the connection fails, try another proxy.
 337     result = ReconsiderProxyAfterError(result);
 338     // ReconsiderProxyAfterError either returns an error (in which case it is
 339     // not reconsidering a proxy) or returns ERR_IO_PENDING if it is considering
 340     // another proxy.
 341     DCHECK_NE(result, net::OK);
 342     if (result == net::ERR_IO_PENDING)
 343       return;  // Proxy reconsideration pending. Return.
 344     LOG(ERROR) << "Failed to connect to MCS endpoint with error " << result;
 345     UMA_HISTOGRAM_BOOLEAN("GCM.ConnectionSuccessRate", false);
 346     recorder_->RecordConnectionFailure(result);
 347     CloseSocket();
 348     backoff_entry_->InformOfRequest(false);
 349     UMA_HISTOGRAM_SPARSE_SLOWLY("GCM.ConnectionFailureErrorCode", result);
 350
 351     // If there are other endpoints available, use the next endpoint on the
 352     // subsequent retry.
 353     next_endpoint_++;
 354     if (next_endpoint_ >= mcs_endpoints_.size())
 355       next_endpoint_ = 0;
 356     connecting_ = false;
 357     Connect();
 358     return;
 359   }
 360
 361   UMA_HISTOGRAM_BOOLEAN("GCM.ConnectionSuccessRate", true);
 362   UMA_HISTOGRAM_COUNTS("GCM.ConnectionEndpoint", next_endpoint_);
 363   UMA_HISTOGRAM_BOOLEAN("GCM.ConnectedViaProxy",
 364                         !(proxy_info_.is_empty() || proxy_info_.is_direct()));
 365   ReportSuccessfulProxyConnection();
 366   recorder_->RecordConnectionSuccess();
 367
 368   // Reset the endpoint back to the default.
 369   // TODO(zea): consider prioritizing endpoints more intelligently based on
 370   // which ones succeed most for this client? Although that will affect
 371   // measuring the success rate of the default endpoint vs fallback.
 372   last_successful_endpoint_ = next_endpoint_;
 373   next_endpoint_ = 0;
 374   connecting_ = false;
 375   logging_in_ = true;
 376   DVLOG(1) << "MCS endpoint socket connection success, starting login.";
 377   InitHandler();
 378 }
 379
 380 void ConnectionFactoryImpl::ConnectionHandlerCallback(int result) {
 381   DCHECK(!connecting_);
 382   if (result != net::OK) {
 383     // TODO(zea): Consider how to handle errors that may require some sort of
 384     // user intervention (login page, etc.).
 385     UMA_HISTOGRAM_SPARSE_SLOWLY("GCM.ConnectionDisconnectErrorCode", result);
 386     SignalConnectionReset(SOCKET_FAILURE);
 387     return;
 388   }
 389
 390   // Handshake complete, reset backoff. If the login failed with an error,
 391   // the client should invoke SignalConnectionReset(LOGIN_FAILURE), which will
 392   // restore the previous backoff.
 393   DVLOG(1) << "Handshake complete.";
 394   last_login_time_ = NowTicks();
 395   previous_backoff_.swap(backoff_entry_);
 396   backoff_entry_->Reset();
 397   logging_in_ = false;
 398
 399   if (listener_)
 400     listener_->OnConnected(GetCurrentEndpoint(), GetPeerIP());
 401 }
 402
 403 // This has largely been copied from
 404 // HttpStreamFactoryImpl::Job::DoResolveProxyComplete. This should be
 405 // refactored into some common place.
 406 void ConnectionFactoryImpl::OnProxyResolveDone(int status) {
 407   pac_request_ = NULL;
 408   DVLOG(1) << "Proxy resolution status: " << status;
 409
 410   DCHECK_NE(status, net::ERR_IO_PENDING);
 411   if (status == net::OK) {
 412     // Remove unsupported proxies from the list.
 413     proxy_info_.RemoveProxiesWithoutScheme(
 414         net::ProxyServer::SCHEME_DIRECT |
 415         net::ProxyServer::SCHEME_HTTP | net::ProxyServer::SCHEME_HTTPS |
 416         net::ProxyServer::SCHEME_SOCKS4 | net::ProxyServer::SCHEME_SOCKS5);
 417
 418     if (proxy_info_.is_empty()) {
 419       // No proxies/direct to choose from. This happens when we don't support
 420       // any of the proxies in the returned list.
 421       status = net::ERR_NO_SUPPORTED_PROXIES;
 422     }
 423   }
 424
 425   if (status != net::OK) {
 426     // Failed to resolve proxy. Retry later.
 427     OnConnectDone(status);
 428     return;
 429   }
 430
 431   DVLOG(1) << "Resolved proxy with PAC:" << proxy_info_.ToPacString();
 432
 433   net::SSLConfig ssl_config;
 434   gcm_network_session_->ssl_config_service()->GetSSLConfig(&ssl_config);
 435   status = net::InitSocketHandleForTlsConnect(
 436       net::HostPortPair::FromURL(GetCurrentEndpoint()),
 437       gcm_network_session_.get(),
 438       proxy_info_,
 439       ssl_config,
 440       ssl_config,
 441       net::PRIVACY_MODE_DISABLED,
 442       bound_net_log_,
 443       &socket_handle_,
 444       base::Bind(&ConnectionFactoryImpl::OnConnectDone,
 445                  weak_ptr_factory_.GetWeakPtr()));
 446   if (status != net::ERR_IO_PENDING)
 447     OnConnectDone(status);
 448 }
 449
 450 // This has largely been copied from
 451 // HttpStreamFactoryImpl::Job::ReconsiderProxyAfterError. This should be
 452 // refactored into some common place.
 453 // This method reconsiders the proxy on certain errors. If it does reconsider
 454 // a proxy it always returns ERR_IO_PENDING and posts a call to
 455 // OnProxyResolveDone with the result of the reconsideration.
 456 int ConnectionFactoryImpl::ReconsiderProxyAfterError(int error) {
 457   DCHECK(!pac_request_);
 458   DCHECK_NE(error, net::OK);
 459   DCHECK_NE(error, net::ERR_IO_PENDING);
 460   // A failure to resolve the hostname or any error related to establishing a
 461   // TCP connection could be grounds for trying a new proxy configuration.
 462   //
 463   // Why do this when a hostname cannot be resolved?  Some URLs only make sense
 464   // to proxy servers.  The hostname in those URLs might fail to resolve if we
 465   // are still using a non-proxy config.  We need to check if a proxy config
 466   // now exists that corresponds to a proxy server that could load the URL.
 467   //
 468   switch (error) {
 469     case net::ERR_PROXY_CONNECTION_FAILED:
 470     case net::ERR_NAME_NOT_RESOLVED:
 471     case net::ERR_INTERNET_DISCONNECTED:
 472     case net::ERR_ADDRESS_UNREACHABLE:
 473     case net::ERR_CONNECTION_CLOSED:
 474     case net::ERR_CONNECTION_TIMED_OUT:
 475     case net::ERR_CONNECTION_RESET:
 476     case net::ERR_CONNECTION_REFUSED:
 477     case net::ERR_CONNECTION_ABORTED:
 478     case net::ERR_TIMED_OUT:
 479     case net::ERR_TUNNEL_CONNECTION_FAILED:
 480     case net::ERR_SOCKS_CONNECTION_FAILED:
 481     // This can happen in the case of trying to talk to a proxy using SSL, and
 482     // ending up talking to a captive portal that supports SSL instead.
 483     case net::ERR_PROXY_CERTIFICATE_INVALID:
 484     // This can happen when trying to talk SSL to a non-SSL server (Like a
 485     // captive portal).
 486     case net::ERR_SSL_PROTOCOL_ERROR:
 487       break;
 488     case net::ERR_SOCKS_CONNECTION_HOST_UNREACHABLE:
 489       // Remap the SOCKS-specific "host unreachable" error to a more
 490       // generic error code (this way consumers like the link doctor
 491       // know to substitute their error page).
 492       //
 493       // Note that if the host resolving was done by the SOCKS5 proxy, we can't
 494       // differentiate between a proxy-side "host not found" versus a proxy-side
 495       // "address unreachable" error, and will report both of these failures as
 496       // ERR_ADDRESS_UNREACHABLE.
 497       return net::ERR_ADDRESS_UNREACHABLE;
 498     default:
 499       return error;
 500   }
 501
 502   net::SSLConfig ssl_config;
 503   gcm_network_session_->ssl_config_service()->GetSSLConfig(&ssl_config);
 504   if (proxy_info_.is_https() && ssl_config.send_client_cert) {
 505     gcm_network_session_->ssl_client_auth_cache()->Remove(
 506         proxy_info_.proxy_server().host_port_pair());
 507   }
 508
 509   int status = gcm_network_session_->proxy_service()->ReconsiderProxyAfterError(
 510       GetCurrentEndpoint(), net::LOAD_NORMAL, error, &proxy_info_,
 511       base::Bind(&ConnectionFactoryImpl::OnProxyResolveDone,
 512                  weak_ptr_factory_.GetWeakPtr()),
 513       &pac_request_,
 514       NULL,
 515       bound_net_log_);
 516   if (status == net::OK || status == net::ERR_IO_PENDING) {
 517     CloseSocket();
 518   } else {
 519     // If ReconsiderProxyAfterError() failed synchronously, it means
 520     // there was nothing left to fall-back to, so fail the transaction
 521     // with the last connection error we got.
 522     status = error;
 523   }
 524
 525   // If there is new proxy info, post OnProxyResolveDone to retry it. Otherwise,
 526   // if there was an error falling back, fail synchronously.
 527   if (status == net::OK) {
 528     base::MessageLoop::current()->PostTask(
 529         FROM_HERE,
 530         base::Bind(&ConnectionFactoryImpl::OnProxyResolveDone,
 531                    weak_ptr_factory_.GetWeakPtr(), status));
 532     status = net::ERR_IO_PENDING;
 533   }
 534   return status;
 535 }
 536
 537 void ConnectionFactoryImpl::ReportSuccessfulProxyConnection() {
 538   if (gcm_network_session_ && gcm_network_session_->proxy_service())
 539     gcm_network_session_->proxy_service()->ReportSuccess(proxy_info_);
 540 }
 541
 542 void ConnectionFactoryImpl::CloseSocket() {
 543   // The connection handler needs to be reset, else it'll attempt to keep using
 544   // the destroyed socket.
 545   if (connection_handler_)
 546     connection_handler_->Reset();
 547
 548   if (socket_handle_.socket() && socket_handle_.socket()->IsConnected())
 549     socket_handle_.socket()->Disconnect();
 550   socket_handle_.Reset();
 551 }
 552
 553 void ConnectionFactoryImpl::RebuildNetworkSessionAuthCache() {
 554   if (!http_network_session_ || !http_network_session_->http_auth_cache())
 555     return;
 556
 557   gcm_network_session_->http_auth_cache()->UpdateAllFrom(
 558       *http_network_session_->http_auth_cache());
 559 }
 560
 561 }  // namespace gcm