remoting/protocol/jingle_session.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 #include "remoting/protocol/jingle_session.h"
   6
   7 #include "base/bind.h"
   8 #include "base/rand_util.h"
   9 #include "base/single_thread_task_runner.h"
  10 #include "base/stl_util.h"
  11 #include "base/strings/string_number_conversions.h"
  12 #include "base/thread_task_runner_handle.h"
  13 #include "base/time/time.h"
  14 #include "remoting/base/constants.h"
  15 #include "remoting/protocol/authenticator.h"
  16 #include "remoting/protocol/channel_authenticator.h"
  17 #include "remoting/protocol/channel_multiplexer.h"
  18 #include "remoting/protocol/content_description.h"
  19 #include "remoting/protocol/jingle_messages.h"
  20 #include "remoting/protocol/jingle_session_manager.h"
  21 #include "remoting/protocol/pseudotcp_channel_factory.h"
  22 #include "remoting/protocol/quic_channel_factory.h"
  23 #include "remoting/protocol/secure_channel_factory.h"
  24 #include "remoting/protocol/session_config.h"
  25 #include "remoting/protocol/stream_channel_factory.h"
  26 #include "remoting/signaling/iq_sender.h"
  27 #include "third_party/webrtc/libjingle/xmllite/xmlelement.h"
  28 #include "third_party/webrtc/p2p/base/candidate.h"
  29
  30 using buzz::XmlElement;
  31
  32 namespace remoting {
  33 namespace protocol {
  34
  35 namespace {
  36
  37 // Delay after candidate creation before sending transport-info message to
  38 // accumulate multiple candidates. This is an optimization to reduce number of
  39 // transport-info messages.
  40 const int kTransportInfoSendDelayMs = 20;
  41
  42 // How long we should wait for a response from the other end. This value is used
  43 // for all requests except |transport-info|.
  44 const int kDefaultMessageTimeout = 10;
  45
  46 // During a reconnection, it usually takes longer for the peer to respond due to
  47 // pending messages in the channel from the previous session.  From experiment,
  48 // it can take up to 20s for the session to reconnect. To make it safe, setting
  49 // the timeout to 30s.
  50 const int kSessionInitiateAndAcceptTimeout = kDefaultMessageTimeout * 3;
  51
  52 // Timeout for the transport-info messages.
  53 const int kTransportInfoTimeout = 10 * 60;
  54
  55 // Name of the multiplexed channel.
  56 const char kMuxChannelName[] = "mux";
  57
  58 ErrorCode AuthRejectionReasonToErrorCode(
  59     Authenticator::RejectionReason reason) {
  60   switch (reason) {
  61     case Authenticator::INVALID_CREDENTIALS:
  62       return AUTHENTICATION_FAILED;
  63     case Authenticator::PROTOCOL_ERROR:
  64       return INCOMPATIBLE_PROTOCOL;
  65   }
  66   NOTREACHED();
  67   return UNKNOWN_ERROR;
  68 }
  69
  70 }  // namespace
  71
  72 JingleSession::JingleSession(JingleSessionManager* session_manager)
  73     : session_manager_(session_manager),
  74       event_handler_(nullptr),
  75       state_(INITIALIZING),
  76       error_(OK),
  77       weak_factory_(this) {
  78 }
  79
  80 JingleSession::~JingleSession() {
  81   channel_multiplexer_.reset();
  82   quic_channel_factory_.reset();
  83   STLDeleteContainerPointers(pending_requests_.begin(),
  84                              pending_requests_.end());
  85   STLDeleteContainerPointers(transport_info_requests_.begin(),
  86                              transport_info_requests_.end());
  87
  88   DCHECK(channels_.empty());
  89
  90   session_manager_->SessionDestroyed(this);
  91 }
  92
  93 void JingleSession::SetEventHandler(Session::EventHandler* event_handler) {
  94   DCHECK(CalledOnValidThread());
  95   DCHECK(event_handler);
  96   event_handler_ = event_handler;
  97 }
  98
  99 ErrorCode JingleSession::error() {
 100   DCHECK(CalledOnValidThread());
 101   return error_;
 102 }
 103
 104 void JingleSession::StartConnection(const std::string& peer_jid,
 105                                     scoped_ptr<Authenticator> authenticator) {
 106   DCHECK(CalledOnValidThread());
 107   DCHECK(authenticator.get());
 108   DCHECK_EQ(authenticator->state(), Authenticator::MESSAGE_READY);
 109
 110   peer_jid_ = peer_jid;
 111   authenticator_ = authenticator.Pass();
 112
 113   // Generate random session ID. There are usually not more than 1
 114   // concurrent session per host, so a random 64-bit integer provides
 115   // enough entropy. In the worst case connection will fail when two
 116   // clients generate the same session ID concurrently.
 117   session_id_ = base::Int64ToString(base::RandGenerator(kint64max));
 118
 119   quic_channel_factory_.reset(new QuicChannelFactory(session_id_, false));
 120
 121   // Send session-initiate message.
 122   JingleMessage message(peer_jid_, JingleMessage::SESSION_INITIATE,
 123                         session_id_);
 124   message.initiator = session_manager_->signal_strategy_->GetLocalJid();
 125   message.description.reset(new ContentDescription(
 126       session_manager_->protocol_config_->Clone(),
 127       authenticator_->GetNextMessage(),
 128       quic_channel_factory_->CreateSessionInitiateConfigMessage()));
 129   SendMessage(message);
 130
 131   SetState(CONNECTING);
 132 }
 133
 134 void JingleSession::InitializeIncomingConnection(
 135     const JingleMessage& initiate_message,
 136     scoped_ptr<Authenticator> authenticator) {
 137   DCHECK(CalledOnValidThread());
 138   DCHECK(initiate_message.description.get());
 139   DCHECK(authenticator.get());
 140   DCHECK_EQ(authenticator->state(), Authenticator::WAITING_MESSAGE);
 141
 142   peer_jid_ = initiate_message.from;
 143   authenticator_ = authenticator.Pass();
 144   session_id_ = initiate_message.sid;
 145
 146   SetState(ACCEPTING);
 147
 148   config_ =
 149       SessionConfig::SelectCommon(initiate_message.description->config(),
 150                                   session_manager_->protocol_config_.get());
 151   if (!config_) {
 152     LOG(WARNING) << "Rejecting connection from " << peer_jid_
 153                  << " because no compatible configuration has been found.";
 154     CloseInternal(INCOMPATIBLE_PROTOCOL);
 155     return;
 156   }
 157
 158   if (config_->is_using_quic()) {
 159     quic_channel_factory_.reset(new QuicChannelFactory(session_id_, true));
 160     if (!quic_channel_factory_->ProcessSessionInitiateConfigMessage(
 161             initiate_message.description->quic_config_message())) {
 162       CloseInternal(INCOMPATIBLE_PROTOCOL);
 163     }
 164   }
 165 }
 166
 167 void JingleSession::AcceptIncomingConnection(
 168     const JingleMessage& initiate_message) {
 169   DCHECK(config_);
 170
 171   // Process the first authentication message.
 172   const buzz::XmlElement* first_auth_message =
 173       initiate_message.description->authenticator_message();
 174
 175   if (!first_auth_message) {
 176     CloseInternal(INCOMPATIBLE_PROTOCOL);
 177     return;
 178   }
 179
 180   DCHECK_EQ(authenticator_->state(), Authenticator::WAITING_MESSAGE);
 181   // |authenticator_| is owned, so Unretained() is safe here.
 182   authenticator_->ProcessMessage(first_auth_message, base::Bind(
 183       &JingleSession::ContinueAcceptIncomingConnection,
 184       base::Unretained(this)));
 185 }
 186
 187 void JingleSession::ContinueAcceptIncomingConnection() {
 188   DCHECK_NE(authenticator_->state(), Authenticator::PROCESSING_MESSAGE);
 189   if (authenticator_->state() == Authenticator::REJECTED) {
 190     CloseInternal(AuthRejectionReasonToErrorCode(
 191         authenticator_->rejection_reason()));
 192     return;
 193   }
 194
 195   // Send the session-accept message.
 196   JingleMessage message(peer_jid_, JingleMessage::SESSION_ACCEPT,
 197                         session_id_);
 198
 199   scoped_ptr<buzz::XmlElement> auth_message;
 200   if (authenticator_->state() == Authenticator::MESSAGE_READY)
 201     auth_message = authenticator_->GetNextMessage();
 202
 203   std::string quic_config;
 204   if (config_->is_using_quic())
 205     quic_config = quic_channel_factory_->CreateSessionAcceptConfigMessage();
 206   message.description.reset(
 207       new ContentDescription(CandidateSessionConfig::CreateFrom(*config_),
 208                              auth_message.Pass(), quic_config));
 209   SendMessage(message);
 210
 211   // Update state.
 212   SetState(CONNECTED);
 213
 214   if (authenticator_->state() == Authenticator::ACCEPTED) {
 215     OnAuthenticated();
 216   } else {
 217     DCHECK_EQ(authenticator_->state(), Authenticator::WAITING_MESSAGE);
 218     if (authenticator_->started()) {
 219       SetState(AUTHENTICATING);
 220     }
 221   }
 222 }
 223
 224 const std::string& JingleSession::jid() {
 225   DCHECK(CalledOnValidThread());
 226   return peer_jid_;
 227 }
 228
 229 const SessionConfig& JingleSession::config() {
 230   DCHECK(CalledOnValidThread());
 231   return *config_;
 232 }
 233
 234 StreamChannelFactory* JingleSession::GetTransportChannelFactory() {
 235   DCHECK(CalledOnValidThread());
 236   return secure_channel_factory_.get();
 237 }
 238
 239 StreamChannelFactory* JingleSession::GetMultiplexedChannelFactory() {
 240   DCHECK(CalledOnValidThread());
 241   if (!channel_multiplexer_.get()) {
 242     channel_multiplexer_.reset(
 243         new ChannelMultiplexer(GetTransportChannelFactory(), kMuxChannelName));
 244   }
 245   return channel_multiplexer_.get();
 246 }
 247
 248 StreamChannelFactory* JingleSession::GetQuicChannelFactory() {
 249   DCHECK(CalledOnValidThread());
 250   return quic_channel_factory_.get();
 251 }
 252
 253 void JingleSession::Close() {
 254   DCHECK(CalledOnValidThread());
 255
 256   CloseInternal(OK);
 257 }
 258
 259 void JingleSession::AddPendingRemoteTransportInfo(Transport* channel) {
 260   std::list<JingleMessage::IceCredentials>::iterator credentials =
 261       pending_remote_ice_credentials_.begin();
 262   while (credentials != pending_remote_ice_credentials_.end()) {
 263     if (credentials->channel == channel->name()) {
 264       channel->SetRemoteCredentials(credentials->ufrag, credentials->password);
 265       credentials = pending_remote_ice_credentials_.erase(credentials);
 266     } else {
 267       ++credentials;
 268     }
 269   }
 270
 271   std::list<JingleMessage::NamedCandidate>::iterator candidate =
 272       pending_remote_candidates_.begin();
 273   while (candidate != pending_remote_candidates_.end()) {
 274     if (candidate->name == channel->name()) {
 275       channel->AddRemoteCandidate(candidate->candidate);
 276       candidate = pending_remote_candidates_.erase(candidate);
 277     } else {
 278       ++candidate;
 279     }
 280   }
 281 }
 282
 283 void JingleSession::CreateChannel(const std::string& name,
 284                                   const ChannelCreatedCallback& callback) {
 285   DCHECK(!channels_[name]);
 286
 287   scoped_ptr<Transport> channel =
 288       session_manager_->transport_factory_->CreateTransport();
 289   channel->Connect(name, this, callback);
 290   AddPendingRemoteTransportInfo(channel.get());
 291   channels_[name] = channel.release();
 292 }
 293
 294 void JingleSession::CancelChannelCreation(const std::string& name) {
 295   ChannelsMap::iterator it = channels_.find(name);
 296   if (it != channels_.end()) {
 297     DCHECK(!it->second->is_connected());
 298     delete it->second;
 299     DCHECK(channels_.find(name) == channels_.end());
 300   }
 301 }
 302
 303 void JingleSession::OnTransportIceCredentials(Transport* transport,
 304                                               const std::string& ufrag,
 305                                               const std::string& password) {
 306   EnsurePendingTransportInfoMessage();
 307   pending_transport_info_message_->ice_credentials.push_back(
 308       JingleMessage::IceCredentials(transport->name(), ufrag, password));
 309 }
 310
 311 void JingleSession::OnTransportCandidate(Transport* transport,
 312                                          const cricket::Candidate& candidate) {
 313   EnsurePendingTransportInfoMessage();
 314   pending_transport_info_message_->candidates.push_back(
 315       JingleMessage::NamedCandidate(transport->name(), candidate));
 316 }
 317
 318 void JingleSession::OnTransportRouteChange(Transport* transport,
 319                                            const TransportRoute& route) {
 320   if (event_handler_)
 321     event_handler_->OnSessionRouteChange(transport->name(), route);
 322 }
 323
 324 void JingleSession::OnTransportFailed(Transport* transport) {
 325   CloseInternal(CHANNEL_CONNECTION_ERROR);
 326 }
 327
 328 void JingleSession::OnTransportDeleted(Transport* transport) {
 329   ChannelsMap::iterator it = channels_.find(transport->name());
 330   DCHECK_EQ(it->second, transport);
 331   channels_.erase(it);
 332 }
 333
 334 void JingleSession::SendMessage(const JingleMessage& message) {
 335   scoped_ptr<IqRequest> request = session_manager_->iq_sender()->SendIq(
 336       message.ToXml(),
 337       base::Bind(&JingleSession::OnMessageResponse,
 338                  base::Unretained(this),
 339                  message.action));
 340
 341   int timeout = kDefaultMessageTimeout;
 342   if (message.action == JingleMessage::SESSION_INITIATE ||
 343       message.action == JingleMessage::SESSION_ACCEPT) {
 344     timeout = kSessionInitiateAndAcceptTimeout;
 345   }
 346   if (request) {
 347     request->SetTimeout(base::TimeDelta::FromSeconds(timeout));
 348     pending_requests_.insert(request.release());
 349   } else {
 350     LOG(ERROR) << "Failed to send a "
 351                << JingleMessage::GetActionName(message.action) << " message";
 352   }
 353 }
 354
 355 void JingleSession::OnMessageResponse(
 356     JingleMessage::ActionType request_type,
 357     IqRequest* request,
 358     const buzz::XmlElement* response) {
 359   // Delete the request from the list of pending requests.
 360   pending_requests_.erase(request);
 361   delete request;
 362
 363   // Ignore all responses after session was closed.
 364   if (state_ == CLOSED || state_ == FAILED)
 365     return;
 366
 367   std::string type_str = JingleMessage::GetActionName(request_type);
 368
 369   // |response| will be nullptr if the request timed out.
 370   if (!response) {
 371     LOG(ERROR) << type_str << " request timed out.";
 372     CloseInternal(SIGNALING_TIMEOUT);
 373     return;
 374   } else {
 375     const std::string& type =
 376         response->Attr(buzz::QName(std::string(), "type"));
 377     if (type != "result") {
 378       LOG(ERROR) << "Received error in response to " << type_str
 379                  << " message: \"" << response->Str()
 380                  << "\". Terminating the session.";
 381
 382       // TODO(sergeyu): There may be different reasons for error
 383       // here. Parse the response stanza to find failure reason.
 384       CloseInternal(PEER_IS_OFFLINE);
 385     }
 386   }
 387 }
 388
 389 void JingleSession::EnsurePendingTransportInfoMessage() {
 390   // |transport_info_timer_| must be running iff
 391   // |pending_transport_info_message_| exists.
 392   DCHECK_EQ(pending_transport_info_message_ != nullptr,
 393             transport_info_timer_.IsRunning());
 394
 395   if (!pending_transport_info_message_) {
 396     pending_transport_info_message_.reset(new JingleMessage(
 397         peer_jid_, JingleMessage::TRANSPORT_INFO, session_id_));
 398     // Delay sending the new candidates in case we get more candidates
 399     // that we can send in one message.
 400     transport_info_timer_.Start(
 401         FROM_HERE, base::TimeDelta::FromMilliseconds(kTransportInfoSendDelayMs),
 402         this, &JingleSession::SendTransportInfo);
 403   }
 404 }
 405
 406 void JingleSession::SendTransportInfo() {
 407   DCHECK(pending_transport_info_message_);
 408
 409   scoped_ptr<IqRequest> request = session_manager_->iq_sender()->SendIq(
 410       pending_transport_info_message_->ToXml(),
 411       base::Bind(&JingleSession::OnTransportInfoResponse,
 412                  base::Unretained(this)));
 413   pending_transport_info_message_.reset();
 414   if (request) {
 415     request->SetTimeout(base::TimeDelta::FromSeconds(kTransportInfoTimeout));
 416     transport_info_requests_.push_back(request.release());
 417   } else {
 418     LOG(ERROR) << "Failed to send a transport-info message";
 419   }
 420 }
 421
 422 void JingleSession::OnTransportInfoResponse(IqRequest* request,
 423                                             const buzz::XmlElement* response) {
 424   DCHECK(!transport_info_requests_.empty());
 425
 426   // Consider transport-info requests sent before this one lost and delete
 427   // corresponding IqRequest objects.
 428   while (transport_info_requests_.front() != request) {
 429     delete transport_info_requests_.front();
 430     transport_info_requests_.pop_front();
 431   }
 432
 433   // Delete the |request| itself.
 434   DCHECK_EQ(request, transport_info_requests_.front());
 435   delete request;
 436   transport_info_requests_.pop_front();
 437
 438   // Ignore transport-info timeouts.
 439   if (!response) {
 440     LOG(ERROR) << "transport-info request has timed out.";
 441     return;
 442   }
 443
 444   const std::string& type = response->Attr(buzz::QName(std::string(), "type"));
 445   if (type != "result") {
 446     LOG(ERROR) << "Received error in response to transport-info message: \""
 447                << response->Str() << "\". Terminating the session.";
 448     CloseInternal(PEER_IS_OFFLINE);
 449   }
 450 }
 451
 452 void JingleSession::OnIncomingMessage(const JingleMessage& message,
 453                                       const ReplyCallback& reply_callback) {
 454   DCHECK(CalledOnValidThread());
 455
 456   if (message.from != peer_jid_) {
 457     // Ignore messages received from a different Jid.
 458     reply_callback.Run(JingleMessageReply::INVALID_SID);
 459     return;
 460   }
 461
 462   switch (message.action) {
 463     case JingleMessage::SESSION_ACCEPT:
 464       OnAccept(message, reply_callback);
 465       break;
 466
 467     case JingleMessage::SESSION_INFO:
 468       OnSessionInfo(message, reply_callback);
 469       break;
 470
 471     case JingleMessage::TRANSPORT_INFO:
 472       reply_callback.Run(JingleMessageReply::NONE);
 473       ProcessTransportInfo(message);
 474       break;
 475
 476     case JingleMessage::SESSION_TERMINATE:
 477       OnTerminate(message, reply_callback);
 478       break;
 479
 480     default:
 481       reply_callback.Run(JingleMessageReply::UNEXPECTED_REQUEST);
 482   }
 483 }
 484
 485 void JingleSession::OnAccept(const JingleMessage& message,
 486                              const ReplyCallback& reply_callback) {
 487   if (state_ != CONNECTING) {
 488     reply_callback.Run(JingleMessageReply::UNEXPECTED_REQUEST);
 489     return;
 490   }
 491
 492   reply_callback.Run(JingleMessageReply::NONE);
 493
 494   const buzz::XmlElement* auth_message =
 495       message.description->authenticator_message();
 496   if (!auth_message) {
 497     DLOG(WARNING) << "Received session-accept without authentication message ";
 498     CloseInternal(INCOMPATIBLE_PROTOCOL);
 499     return;
 500   }
 501
 502   if (!InitializeConfigFromDescription(message.description.get())) {
 503     CloseInternal(INCOMPATIBLE_PROTOCOL);
 504     return;
 505   }
 506
 507   if (config_->is_using_quic()) {
 508     if (!quic_channel_factory_->ProcessSessionAcceptConfigMessage(
 509             message.description->quic_config_message())) {
 510       CloseInternal(INCOMPATIBLE_PROTOCOL);
 511       return;
 512     }
 513   } else {
 514     quic_channel_factory_.reset();
 515   }
 516
 517   SetState(CONNECTED);
 518
 519   DCHECK(authenticator_->state() == Authenticator::WAITING_MESSAGE);
 520   authenticator_->ProcessMessage(auth_message, base::Bind(
 521       &JingleSession::ProcessAuthenticationStep,base::Unretained(this)));
 522 }
 523
 524 void JingleSession::OnSessionInfo(const JingleMessage& message,
 525                                   const ReplyCallback& reply_callback) {
 526   if (!message.info.get() ||
 527       !Authenticator::IsAuthenticatorMessage(message.info.get())) {
 528     reply_callback.Run(JingleMessageReply::UNSUPPORTED_INFO);
 529     return;
 530   }
 531
 532   if ((state_ != CONNECTED && state_ != AUTHENTICATING) ||
 533       authenticator_->state() != Authenticator::WAITING_MESSAGE) {
 534     LOG(WARNING) << "Received unexpected authenticator message "
 535                  << message.info->Str();
 536     reply_callback.Run(JingleMessageReply::UNEXPECTED_REQUEST);
 537     CloseInternal(INCOMPATIBLE_PROTOCOL);
 538     return;
 539   }
 540
 541   reply_callback.Run(JingleMessageReply::NONE);
 542
 543   authenticator_->ProcessMessage(message.info.get(), base::Bind(
 544       &JingleSession::ProcessAuthenticationStep, base::Unretained(this)));
 545 }
 546
 547 void JingleSession::ProcessTransportInfo(const JingleMessage& message) {
 548   for (std::list<JingleMessage::IceCredentials>::const_iterator it =
 549            message.ice_credentials.begin();
 550        it != message.ice_credentials.end(); ++it) {
 551     ChannelsMap::iterator channel = channels_.find(it->channel);
 552     if (channel != channels_.end()) {
 553       channel->second->SetRemoteCredentials(it->ufrag, it->password);
 554     } else {
 555       // Transport info was received before the channel was created.
 556       // This could happen due to messages being reordered on the wire.
 557       pending_remote_ice_credentials_.push_back(*it);
 558     }
 559   }
 560
 561   for (std::list<JingleMessage::NamedCandidate>::const_iterator it =
 562            message.candidates.begin();
 563        it != message.candidates.end(); ++it) {
 564     ChannelsMap::iterator channel = channels_.find(it->name);
 565     if (channel != channels_.end()) {
 566       channel->second->AddRemoteCandidate(it->candidate);
 567     } else {
 568       // Transport info was received before the channel was created.
 569       // This could happen due to messages being reordered on the wire.
 570       pending_remote_candidates_.push_back(*it);
 571     }
 572   }
 573 }
 574
 575 void JingleSession::OnTerminate(const JingleMessage& message,
 576                                 const ReplyCallback& reply_callback) {
 577   if (!is_session_active()) {
 578     LOG(WARNING) << "Received unexpected session-terminate message.";
 579     reply_callback.Run(JingleMessageReply::UNEXPECTED_REQUEST);
 580     return;
 581   }
 582
 583   reply_callback.Run(JingleMessageReply::NONE);
 584
 585   switch (message.reason) {
 586     case JingleMessage::SUCCESS:
 587       if (state_ == CONNECTING) {
 588         error_ = SESSION_REJECTED;
 589       } else {
 590         error_ = OK;
 591       }
 592       break;
 593     case JingleMessage::DECLINE:
 594       error_ = AUTHENTICATION_FAILED;
 595       break;
 596     case JingleMessage::CANCEL:
 597       error_ = HOST_OVERLOAD;
 598       break;
 599     case JingleMessage::GENERAL_ERROR:
 600       error_ = CHANNEL_CONNECTION_ERROR;
 601       break;
 602     case JingleMessage::INCOMPATIBLE_PARAMETERS:
 603       error_ = INCOMPATIBLE_PROTOCOL;
 604       break;
 605     default:
 606       error_ = UNKNOWN_ERROR;
 607   }
 608
 609   if (error_ != OK) {
 610     SetState(FAILED);
 611   } else {
 612     SetState(CLOSED);
 613   }
 614 }
 615
 616 bool JingleSession::InitializeConfigFromDescription(
 617     const ContentDescription* description) {
 618   DCHECK(description);
 619   config_ = SessionConfig::GetFinalConfig(description->config());
 620   if (!config_) {
 621     LOG(ERROR) << "session-accept does not specify configuration";
 622     return false;
 623   }
 624   if (!session_manager_->protocol_config_->IsSupported(*config_)) {
 625     LOG(ERROR) << "session-accept specifies an invalid configuration";
 626     return false;
 627   }
 628
 629   return true;
 630 }
 631
 632 void JingleSession::ProcessAuthenticationStep() {
 633   DCHECK(CalledOnValidThread());
 634   DCHECK_NE(authenticator_->state(), Authenticator::PROCESSING_MESSAGE);
 635
 636   if (state_ != CONNECTED && state_ != AUTHENTICATING) {
 637     DCHECK(state_ == FAILED || state_ == CLOSED);
 638     // The remote host closed the connection while the authentication was being
 639     // processed asynchronously, nothing to do.
 640     return;
 641   }
 642
 643   if (authenticator_->state() == Authenticator::MESSAGE_READY) {
 644     JingleMessage message(peer_jid_, JingleMessage::SESSION_INFO, session_id_);
 645     message.info = authenticator_->GetNextMessage();
 646     DCHECK(message.info.get());
 647     SendMessage(message);
 648   }
 649   DCHECK_NE(authenticator_->state(), Authenticator::MESSAGE_READY);
 650
 651   // The current JingleSession object can be destroyed by event_handler of
 652   // SetState(AUTHENTICATING) and cause subsequent dereferencing of the this
 653   // pointer to crash.  To protect against it, we run ContinueAuthenticationStep
 654   // asychronously using a weak pointer.
 655   base::ThreadTaskRunnerHandle::Get()->PostTask(
 656     FROM_HERE,
 657     base::Bind(&JingleSession::ContinueAuthenticationStep,
 658                weak_factory_.GetWeakPtr()));
 659
 660   if (authenticator_->started()) {
 661     SetState(AUTHENTICATING);
 662   }
 663 }
 664
 665 void JingleSession::ContinueAuthenticationStep() {
 666   if (authenticator_->state() == Authenticator::ACCEPTED) {
 667     OnAuthenticated();
 668   } else if (authenticator_->state() == Authenticator::REJECTED) {
 669     CloseInternal(AuthRejectionReasonToErrorCode(
 670         authenticator_->rejection_reason()));
 671   }
 672 }
 673
 674 void JingleSession::OnAuthenticated() {
 675   pseudotcp_channel_factory_.reset(new PseudoTcpChannelFactory(this));
 676   secure_channel_factory_.reset(
 677       new SecureChannelFactory(pseudotcp_channel_factory_.get(),
 678                                authenticator_.get()));
 679
 680   if (quic_channel_factory_)
 681     quic_channel_factory_->Start(this, authenticator_->GetAuthKey());
 682
 683   SetState(AUTHENTICATED);
 684 }
 685
 686 void JingleSession::CloseInternal(ErrorCode error) {
 687   DCHECK(CalledOnValidThread());
 688
 689   if (is_session_active()) {
 690     // Send session-terminate message with the appropriate error code.
 691     JingleMessage::Reason reason;
 692     switch (error) {
 693       case OK:
 694         reason = JingleMessage::SUCCESS;
 695         break;
 696       case SESSION_REJECTED:
 697       case AUTHENTICATION_FAILED:
 698         reason = JingleMessage::DECLINE;
 699         break;
 700       case INCOMPATIBLE_PROTOCOL:
 701         reason = JingleMessage::INCOMPATIBLE_PARAMETERS;
 702         break;
 703       case HOST_OVERLOAD:
 704         reason = JingleMessage::CANCEL;
 705         break;
 706       default:
 707         reason = JingleMessage::GENERAL_ERROR;
 708     }
 709
 710     JingleMessage message(peer_jid_, JingleMessage::SESSION_TERMINATE,
 711                           session_id_);
 712     message.reason = reason;
 713     SendMessage(message);
 714   }
 715
 716   error_ = error;
 717
 718   if (state_ != FAILED && state_ != CLOSED) {
 719     if (error != OK) {
 720       SetState(FAILED);
 721     } else {
 722       SetState(CLOSED);
 723     }
 724   }
 725 }
 726
 727 void JingleSession::SetState(State new_state) {
 728   DCHECK(CalledOnValidThread());
 729
 730   if (new_state != state_) {
 731     DCHECK_NE(state_, CLOSED);
 732     DCHECK_NE(state_, FAILED);
 733
 734     state_ = new_state;
 735     if (event_handler_)
 736       event_handler_->OnSessionStateChange(new_state);
 737   }
 738 }
 739
 740 bool JingleSession::is_session_active() {
 741   return state_ == CONNECTING || state_ == ACCEPTING || state_ == CONNECTED ||
 742         state_ == AUTHENTICATING || state_ == AUTHENTICATED;
 743 }
 744
 745 }  // namespace protocol
 746 }  // namespace remoting