src/remoting/host/remoting_me2me_host.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 // This file implements a standalone host process for Me2Me.
   6
   7 #include <string>
   8
   9 #include "base/at_exit.h"
  10 #include "base/bind.h"
  11 #include "base/callback.h"
  12 #include "base/command_line.h"
  13 #include "base/debug/alias.h"
  14 #include "base/files/file_path.h"
  15 #include "base/files/file_util.h"
  16 #include "base/memory/scoped_ptr.h"
  17 #include "base/message_loop/message_loop.h"
  18 #include "base/single_thread_task_runner.h"
  19 #include "base/strings/string_number_conversions.h"
  20 #include "base/strings/string_util.h"
  21 #include "base/strings/utf_string_conversions.h"
  22 #include "base/synchronization/waitable_event.h"
  23 #include "base/threading/thread.h"
  24 #include "build/build_config.h"
  25 #include "crypto/nss_util.h"
  26 #include "ipc/ipc_channel.h"
  27 #include "ipc/ipc_channel_proxy.h"
  28 #include "ipc/ipc_listener.h"
  29 #include "media/base/media.h"
  30 #include "net/base/network_change_notifier.h"
  31 #include "net/socket/client_socket_factory.h"
  32 #include "net/socket/ssl_server_socket.h"
  33 #include "net/url_request/url_fetcher.h"
  34 #include "remoting/base/auto_thread_task_runner.h"
  35 #include "remoting/base/breakpad.h"
  36 #include "remoting/base/constants.h"
  37 #include "remoting/base/logging.h"
  38 #include "remoting/base/rsa_key_pair.h"
  39 #include "remoting/base/service_urls.h"
  40 #include "remoting/base/util.h"
  41 #include "remoting/host/branding.h"
  42 #include "remoting/host/chromoting_host.h"
  43 #include "remoting/host/chromoting_host_context.h"
  44 #include "remoting/host/chromoting_messages.h"
  45 #include "remoting/host/config_file_watcher.h"
  46 #include "remoting/host/config_watcher.h"
  47 #include "remoting/host/desktop_environment.h"
  48 #include "remoting/host/desktop_session_connector.h"
  49 #include "remoting/host/dns_blackhole_checker.h"
  50 #include "remoting/host/heartbeat_sender.h"
  51 #include "remoting/host/host_change_notification_listener.h"
  52 #include "remoting/host/host_config.h"
  53 #include "remoting/host/host_event_logger.h"
  54 #include "remoting/host/host_exit_codes.h"
  55 #include "remoting/host/host_main.h"
  56 #include "remoting/host/host_status_logger.h"
  57 #include "remoting/host/host_status_sender.h"
  58 #include "remoting/host/ipc_constants.h"
  59 #include "remoting/host/ipc_desktop_environment.h"
  60 #include "remoting/host/ipc_host_event_logger.h"
  61 #include "remoting/host/json_host_config.h"
  62 #include "remoting/host/logging.h"
  63 #include "remoting/host/me2me_desktop_environment.h"
  64 #include "remoting/host/pairing_registry_delegate.h"
  65 #include "remoting/host/policy_hack/policy_watcher.h"
  66 #include "remoting/host/session_manager_factory.h"
  67 #include "remoting/host/signaling_connector.h"
  68 #include "remoting/host/single_window_desktop_environment.h"
  69 #include "remoting/host/token_validator_factory_impl.h"
  70 #include "remoting/host/usage_stats_consent.h"
  71 #include "remoting/host/username.h"
  72 #include "remoting/host/video_frame_recorder_host_extension.h"
  73 #include "remoting/protocol/me2me_host_authenticator_factory.h"
  74 #include "remoting/protocol/network_settings.h"
  75 #include "remoting/protocol/pairing_registry.h"
  76 #include "remoting/protocol/token_validator.h"
  77 #include "remoting/signaling/xmpp_signal_strategy.h"
  78
  79 #if defined(OS_POSIX)
  80 #include <signal.h>
  81 #include <sys/types.h>
  82 #include <unistd.h>
  83 #include "base/file_descriptor_posix.h"
  84 #include "remoting/host/pam_authorization_factory_posix.h"
  85 #include "remoting/host/posix/signal_handler.h"
  86 #endif  // defined(OS_POSIX)
  87
  88 #if defined(OS_MACOSX)
  89 #include "base/mac/scoped_cftyperef.h"
  90 #endif  // defined(OS_MACOSX)
  91
  92 #if defined(OS_LINUX)
  93 #include <gtk/gtk.h>
  94 #include <X11/Xlib.h>
  95 #include "remoting/host/audio_capturer_linux.h"
  96 #endif  // defined(OS_LINUX)
  97
  98 #if defined(OS_WIN)
  99 #include <commctrl.h>
 100 #include "base/win/registry.h"
 101 #include "base/win/scoped_handle.h"
 102 #include "remoting/host/pairing_registry_delegate_win.h"
 103 #include "remoting/host/win/session_desktop_environment.h"
 104 #endif  // defined(OS_WIN)
 105
 106 using remoting::protocol::PairingRegistry;
 107 using remoting::protocol::NetworkSettings;
 108
 109 namespace {
 110
 111 // This is used for tagging system event logs.
 112 const char kApplicationName[] = "chromoting";
 113
 114 #if defined(OS_LINUX)
 115 // The command line switch used to pass name of the pipe to capture audio on
 116 // linux.
 117 const char kAudioPipeSwitchName[] = "audio-pipe-name";
 118
 119 // The command line switch used to pass name of the unix domain socket used to
 120 // listen for gnubby requests.
 121 const char kAuthSocknameSwitchName[] = "ssh-auth-sockname";
 122 #endif  // defined(OS_LINUX)
 123
 124 // The command line switch used by the parent to request the host to signal it
 125 // when it is successfully started.
 126 const char kSignalParentSwitchName[] = "signal-parent";
 127
 128 // Command line switch used to enable VP9 encoding.
 129 const char kEnableVp9SwitchName[] = "enable-vp9";
 130
 131 // Command line switch used to enable and configure the frame-recorder.
 132 const char kFrameRecorderBufferKbName[] = "frame-recorder-buffer-kb";
 133
 134 // Value used for --host-config option to indicate that the path must be read
 135 // from stdin.
 136 const char kStdinConfigPath[] = "-";
 137
 138 const char kWindowIdSwitchName[] = "window-id";
 139
 140 }  // namespace
 141
 142 namespace remoting {
 143
 144 class HostProcess
 145     : public ConfigWatcher::Delegate,
 146       public HeartbeatSender::Listener,
 147       public HostChangeNotificationListener::Listener,
 148       public IPC::Listener,
 149       public base::RefCountedThreadSafe<HostProcess> {
 150  public:
 151   HostProcess(scoped_ptr<ChromotingHostContext> context,
 152               int* exit_code_out);
 153
 154   // ConfigWatcher::Delegate interface.
 155   virtual void OnConfigUpdated(const std::string& serialized_config) OVERRIDE;
 156   virtual void OnConfigWatcherError() OVERRIDE;
 157
 158   // IPC::Listener implementation.
 159   virtual bool OnMessageReceived(const IPC::Message& message) OVERRIDE;
 160   virtual void OnChannelError() OVERRIDE;
 161
 162   // HeartbeatSender::Listener overrides.
 163   virtual void OnHeartbeatSuccessful() OVERRIDE;
 164   virtual void OnUnknownHostIdError() OVERRIDE;
 165
 166   // HostChangeNotificationListener::Listener overrides.
 167   virtual void OnHostDeleted() OVERRIDE;
 168
 169   // Initializes the pairing registry on Windows.
 170   void OnInitializePairingRegistry(
 171       IPC::PlatformFileForTransit privileged_key,
 172       IPC::PlatformFileForTransit unprivileged_key);
 173
 174  private:
 175   enum HostState {
 176     // Host process has just been started. Waiting for config and policies to be
 177     // read from the disk.
 178     HOST_INITIALIZING,
 179
 180     // Host is started and running.
 181     HOST_STARTED,
 182
 183     // Host is being stopped and will need to be started again.
 184     HOST_STOPPING_TO_RESTART,
 185
 186     // Host is being stopped.
 187     HOST_STOPPING,
 188
 189     // Host has been stopped.
 190     HOST_STOPPED,
 191
 192     // Allowed state transitions:
 193     //   INITIALIZING->STARTED
 194     //   INITIALIZING->STOPPED
 195     //   STARTED->STOPPING_TO_RESTART
 196     //   STARTED->STOPPING
 197     //   STOPPING_TO_RESTART->STARTED
 198     //   STOPPING_TO_RESTART->STOPPING
 199     //   STOPPING->STOPPED
 200     //   STOPPED->STARTED
 201     //
 202     // |host_| must be NULL in INITIALIZING and STOPPED states and not-NULL in
 203     // all other states.
 204   };
 205
 206   friend class base::RefCountedThreadSafe<HostProcess>;
 207   virtual ~HostProcess();
 208
 209   void StartOnNetworkThread();
 210
 211 #if defined(OS_POSIX)
 212   // Callback passed to RegisterSignalHandler() to handle SIGTERM events.
 213   void SigTermHandler(int signal_number);
 214 #endif
 215
 216   // Called to initialize resources on the UI thread.
 217   void StartOnUiThread();
 218
 219   // Initializes IPC control channel and config file path from |cmd_line|.
 220   // Called on the UI thread.
 221   bool InitWithCommandLine(const base::CommandLine* cmd_line);
 222
 223   // Called on the UI thread to start monitoring the configuration file.
 224   void StartWatchingConfigChanges();
 225
 226   // Called on the network thread to set the host's Authenticator factory.
 227   void CreateAuthenticatorFactory();
 228
 229   // Tear down resources that run on the UI thread.
 230   void ShutdownOnUiThread();
 231
 232   // Applies the host config, returning true if successful.
 233   bool ApplyConfig(scoped_ptr<JsonHostConfig> config);
 234
 235   // Handles policy updates, by calling On*PolicyUpdate methods.
 236   void OnPolicyUpdate(scoped_ptr<base::DictionaryValue> policies);
 237   void ApplyHostDomainPolicy();
 238   void ApplyUsernamePolicy();
 239   bool OnHostDomainPolicyUpdate(base::DictionaryValue* policies);
 240   bool OnUsernamePolicyUpdate(base::DictionaryValue* policies);
 241   bool OnNatPolicyUpdate(base::DictionaryValue* policies);
 242   bool OnRelayPolicyUpdate(base::DictionaryValue* policies);
 243   bool OnUdpPortPolicyUpdate(base::DictionaryValue* policies);
 244   bool OnCurtainPolicyUpdate(base::DictionaryValue* policies);
 245   bool OnHostTalkGadgetPrefixPolicyUpdate(base::DictionaryValue* policies);
 246   bool OnHostTokenUrlPolicyUpdate(base::DictionaryValue* policies);
 247   bool OnPairingPolicyUpdate(base::DictionaryValue* policies);
 248   bool OnGnubbyAuthPolicyUpdate(base::DictionaryValue* policies);
 249
 250   void StartHost();
 251
 252   void OnAuthFailed();
 253
 254   void RestartHost();
 255
 256   // Stops the host and shuts down the process with the specified |exit_code|.
 257   void ShutdownHost(HostExitCodes exit_code);
 258
 259   void ScheduleHostShutdown();
 260
 261   void ShutdownOnNetworkThread();
 262
 263   // Crashes the process in response to a daemon's request. The daemon passes
 264   // the location of the code that detected the fatal error resulted in this
 265   // request.
 266   void OnCrash(const std::string& function_name,
 267                const std::string& file_name,
 268                const int& line_number);
 269
 270   scoped_ptr<ChromotingHostContext> context_;
 271
 272   // Created on the UI thread but used from the network thread.
 273   scoped_ptr<net::NetworkChangeNotifier> network_change_notifier_;
 274
 275   // Accessed on the UI thread.
 276   scoped_ptr<IPC::ChannelProxy> daemon_channel_;
 277
 278   // XMPP server/remoting bot configuration (initialized from the command line).
 279   XmppSignalStrategy::XmppServerConfig xmpp_server_config_;
 280   std::string directory_bot_jid_;
 281
 282   // Created on the UI thread but used from the network thread.
 283   base::FilePath host_config_path_;
 284   std::string host_config_;
 285   scoped_ptr<DesktopEnvironmentFactory> desktop_environment_factory_;
 286
 287   // Accessed on the network thread.
 288   HostState state_;
 289
 290   scoped_ptr<ConfigWatcher> config_watcher_;
 291
 292   std::string host_id_;
 293   protocol::SharedSecretHash host_secret_hash_;
 294   scoped_refptr<RsaKeyPair> key_pair_;
 295   std::string oauth_refresh_token_;
 296   std::string serialized_config_;
 297   std::string host_owner_;
 298   bool use_service_account_;
 299   bool enable_vp9_;
 300   int64_t frame_recorder_buffer_size_;
 301
 302   scoped_ptr<policy_hack::PolicyWatcher> policy_watcher_;
 303   std::string host_domain_;
 304   bool host_username_match_required_;
 305   bool allow_nat_traversal_;
 306   bool allow_relay_;
 307   int min_udp_port_;
 308   int max_udp_port_;
 309   std::string talkgadget_prefix_;
 310   bool allow_pairing_;
 311
 312   bool curtain_required_;
 313   ThirdPartyAuthConfig third_party_auth_config_;
 314   bool enable_gnubby_auth_;
 315
 316   // Boolean to change flow, where ncessary, if we're
 317   // capturing a window instead of the entire desktop.
 318   bool enable_window_capture_;
 319
 320   // Used to specify which window to stream, if enabled.
 321   webrtc::WindowId window_id_;
 322
 323   scoped_ptr<OAuthTokenGetter> oauth_token_getter_;
 324   scoped_ptr<XmppSignalStrategy> signal_strategy_;
 325   scoped_ptr<SignalingConnector> signaling_connector_;
 326   scoped_ptr<HeartbeatSender> heartbeat_sender_;
 327   scoped_ptr<HostStatusSender> host_status_sender_;
 328   scoped_ptr<HostChangeNotificationListener> host_change_notification_listener_;
 329   scoped_ptr<HostStatusLogger> host_status_logger_;
 330   scoped_ptr<HostEventLogger> host_event_logger_;
 331
 332   scoped_ptr<ChromotingHost> host_;
 333
 334   // Used to keep this HostProcess alive until it is shutdown.
 335   scoped_refptr<HostProcess> self_;
 336
 337 #if defined(REMOTING_MULTI_PROCESS)
 338   DesktopSessionConnector* desktop_session_connector_;
 339 #endif  // defined(REMOTING_MULTI_PROCESS)
 340
 341   int* exit_code_out_;
 342   bool signal_parent_;
 343
 344   scoped_ptr<PairingRegistry::Delegate> pairing_registry_delegate_;
 345 };
 346
 347 HostProcess::HostProcess(scoped_ptr<ChromotingHostContext> context,
 348                          int* exit_code_out)
 349     : context_(context.Pass()),
 350       state_(HOST_INITIALIZING),
 351       use_service_account_(false),
 352       enable_vp9_(false),
 353       frame_recorder_buffer_size_(0),
 354       host_username_match_required_(false),
 355       allow_nat_traversal_(true),
 356       allow_relay_(true),
 357       min_udp_port_(0),
 358       max_udp_port_(0),
 359       allow_pairing_(true),
 360       curtain_required_(false),
 361       enable_gnubby_auth_(false),
 362       enable_window_capture_(false),
 363       window_id_(0),
 364 #if defined(REMOTING_MULTI_PROCESS)
 365       desktop_session_connector_(NULL),
 366 #endif  // defined(REMOTING_MULTI_PROCESS)
 367       self_(this),
 368       exit_code_out_(exit_code_out),
 369       signal_parent_(false) {
 370   StartOnUiThread();
 371 }
 372
 373 HostProcess::~HostProcess() {
 374   // Verify that UI components have been torn down.
 375   DCHECK(!config_watcher_);
 376   DCHECK(!daemon_channel_);
 377   DCHECK(!desktop_environment_factory_);
 378
 379   // We might be getting deleted on one of the threads the |host_context| owns,
 380   // so we need to post it back to the caller thread to safely join & delete the
 381   // threads it contains.  This will go away when we move to AutoThread.
 382   // |context_release()| will null |context_| before the method is invoked, so
 383   // we need to pull out the task-runner on which to call DeleteSoon first.
 384   scoped_refptr<base::SingleThreadTaskRunner> task_runner =
 385       context_->ui_task_runner();
 386   task_runner->DeleteSoon(FROM_HERE, context_.release());
 387 }
 388
 389 bool HostProcess::InitWithCommandLine(const base::CommandLine* cmd_line) {
 390 #if defined(REMOTING_MULTI_PROCESS)
 391   // Parse the handle value and convert it to a handle/file descriptor.
 392   std::string channel_name =
 393       cmd_line->GetSwitchValueASCII(kDaemonPipeSwitchName);
 394
 395   int pipe_handle = 0;
 396   if (channel_name.empty() ||
 397       !base::StringToInt(channel_name, &pipe_handle)) {
 398     LOG(ERROR) << "Invalid '" << kDaemonPipeSwitchName
 399                << "' value: " << channel_name;
 400     return false;
 401   }
 402
 403 #if defined(OS_WIN)
 404   base::win::ScopedHandle pipe(reinterpret_cast<HANDLE>(pipe_handle));
 405   IPC::ChannelHandle channel_handle(pipe.Get());
 406 #elif defined(OS_POSIX)
 407   base::FileDescriptor pipe(pipe_handle, true);
 408   IPC::ChannelHandle channel_handle(channel_name, pipe);
 409 #endif  // defined(OS_POSIX)
 410
 411   // Connect to the daemon process.
 412   daemon_channel_ = IPC::ChannelProxy::Create(channel_handle,
 413                                               IPC::Channel::MODE_CLIENT,
 414                                               this,
 415                                               context_->network_task_runner());
 416 #else  // !defined(REMOTING_MULTI_PROCESS)
 417   // Connect to the daemon process.
 418   std::string channel_name =
 419       cmd_line->GetSwitchValueASCII(kDaemonPipeSwitchName);
 420   if (!channel_name.empty()) {
 421     daemon_channel_ =
 422         IPC::ChannelProxy::Create(channel_name,
 423                                   IPC::Channel::MODE_CLIENT,
 424                                   this,
 425                                   context_->network_task_runner().get());
 426   }
 427
 428   if (cmd_line->HasSwitch(kHostConfigSwitchName)) {
 429     host_config_path_ = cmd_line->GetSwitchValuePath(kHostConfigSwitchName);
 430
 431     // Read config from stdin if necessary.
 432     if (host_config_path_ == base::FilePath(kStdinConfigPath)) {
 433       char buf[4096];
 434       size_t len;
 435       while ((len = fread(buf, 1, sizeof(buf), stdin)) > 0) {
 436         host_config_.append(buf, len);
 437       }
 438     }
 439   } else {
 440     base::FilePath default_config_dir = remoting::GetConfigDir();
 441     host_config_path_ = default_config_dir.Append(kDefaultHostConfigFile);
 442   }
 443
 444   if (host_config_path_ != base::FilePath(kStdinConfigPath) &&
 445       !base::PathExists(host_config_path_)) {
 446     LOG(ERROR) << "Can't find host config at " << host_config_path_.value();
 447     return false;
 448   }
 449 #endif  // !defined(REMOTING_MULTI_PROCESS)
 450
 451   // Ignore certificate requests - the host currently has no client certificate
 452   // support, so ignoring certificate requests allows connecting to servers that
 453   // request, but don't require, a certificate (optional client authentication).
 454   net::URLFetcher::SetIgnoreCertificateRequests(true);
 455
 456   ServiceUrls* service_urls = ServiceUrls::GetInstance();
 457   bool xmpp_server_valid = net::ParseHostAndPort(
 458       service_urls->xmpp_server_address(),
 459       &xmpp_server_config_.host, &xmpp_server_config_.port);
 460   if (!xmpp_server_valid) {
 461     LOG(ERROR) << "Invalid XMPP server: " <<
 462         service_urls->xmpp_server_address();
 463     return false;
 464   }
 465   xmpp_server_config_.use_tls = service_urls->xmpp_server_use_tls();
 466   directory_bot_jid_ = service_urls->directory_bot_jid();
 467
 468   signal_parent_ = cmd_line->HasSwitch(kSignalParentSwitchName);
 469
 470   enable_window_capture_ = cmd_line->HasSwitch(kWindowIdSwitchName);
 471   if (enable_window_capture_) {
 472
 473 #if defined(OS_LINUX) || defined(OS_WIN)
 474     LOG(WARNING) << "Window capturing is not fully supported on Linux or "
 475                     "Windows.";
 476 #endif  // defined(OS_LINUX) || defined(OS_WIN)
 477
 478     // uint32_t is large enough to hold window IDs on all platforms.
 479     uint32_t window_id;
 480     if (base::StringToUint(
 481             cmd_line->GetSwitchValueASCII(kWindowIdSwitchName),
 482             &window_id)) {
 483       window_id_ = static_cast<webrtc::WindowId>(window_id);
 484     } else {
 485       LOG(ERROR) << "Window with window id: " << window_id_
 486                  << " not found. Shutting down host.";
 487       return false;
 488     }
 489   }
 490   return true;
 491 }
 492
 493 void HostProcess::OnConfigUpdated(
 494     const std::string& serialized_config) {
 495   if (!context_->network_task_runner()->BelongsToCurrentThread()) {
 496     context_->network_task_runner()->PostTask(FROM_HERE,
 497         base::Bind(&HostProcess::OnConfigUpdated, this, serialized_config));
 498     return;
 499   }
 500
 501   // Filter out duplicates.
 502   if (serialized_config_ == serialized_config)
 503     return;
 504
 505   HOST_LOG << "Processing new host configuration.";
 506
 507   serialized_config_ = serialized_config;
 508   scoped_ptr<JsonHostConfig> config(new JsonHostConfig(base::FilePath()));
 509   if (!config->SetSerializedData(serialized_config)) {
 510     LOG(ERROR) << "Invalid configuration.";
 511     ShutdownHost(kInvalidHostConfigurationExitCode);
 512     return;
 513   }
 514
 515   if (!ApplyConfig(config.Pass())) {
 516     LOG(ERROR) << "Failed to apply the configuration.";
 517     ShutdownHost(kInvalidHostConfigurationExitCode);
 518     return;
 519   }
 520
 521   if (state_ == HOST_INITIALIZING) {
 522     // TODO(sergeyu): Currently OnPolicyUpdate() assumes that host config is
 523     // already loaded so PolicyWatcher has to be started here. Separate policy
 524     // loading from policy verifications and move |policy_watcher_|
 525     // initialization to StartOnNetworkThread().
 526     policy_watcher_.reset(
 527         policy_hack::PolicyWatcher::Create(context_->file_task_runner()));
 528     policy_watcher_->StartWatching(
 529         base::Bind(&HostProcess::OnPolicyUpdate, base::Unretained(this)));
 530   } else {
 531     // Reapply policies that could be affected by a new config.
 532     ApplyHostDomainPolicy();
 533     ApplyUsernamePolicy();
 534
 535     if (state_ == HOST_STARTED) {
 536       // TODO(sergeyu): Here we assume that PIN is the only part of the config
 537       // that may change while the service is running. Change ApplyConfig() to
 538       // detect other changes in the config and restart host if necessary here.
 539       CreateAuthenticatorFactory();
 540     }
 541   }
 542 }
 543
 544 void HostProcess::OnConfigWatcherError() {
 545   DCHECK(context_->network_task_runner()->BelongsToCurrentThread());
 546   ShutdownHost(kInvalidHostConfigurationExitCode);
 547 }
 548
 549 void HostProcess::StartOnNetworkThread() {
 550   DCHECK(context_->network_task_runner()->BelongsToCurrentThread());
 551
 552 #if !defined(REMOTING_MULTI_PROCESS)
 553   if (host_config_path_ == base::FilePath(kStdinConfigPath)) {
 554     // Process config we've read from stdin.
 555     OnConfigUpdated(host_config_);
 556   } else {
 557     // Start watching the host configuration file.
 558     config_watcher_.reset(new ConfigFileWatcher(context_->network_task_runner(),
 559                                                 context_->file_task_runner(),
 560                                                 host_config_path_));
 561     config_watcher_->Watch(this);
 562   }
 563 #endif  // !defined(REMOTING_MULTI_PROCESS)
 564
 565 #if defined(OS_POSIX)
 566   remoting::RegisterSignalHandler(
 567       SIGTERM,
 568       base::Bind(&HostProcess::SigTermHandler, base::Unretained(this)));
 569 #endif  // defined(OS_POSIX)
 570 }
 571
 572 #if defined(OS_POSIX)
 573 void HostProcess::SigTermHandler(int signal_number) {
 574   DCHECK(signal_number == SIGTERM);
 575   DCHECK(context_->network_task_runner()->BelongsToCurrentThread());
 576   HOST_LOG << "Caught SIGTERM: Shutting down...";
 577   ShutdownHost(kSuccessExitCode);
 578 }
 579 #endif  // OS_POSIX
 580
 581 void HostProcess::CreateAuthenticatorFactory() {
 582   DCHECK(context_->network_task_runner()->BelongsToCurrentThread());
 583
 584   if (state_ != HOST_STARTED)
 585     return;
 586
 587   std::string local_certificate = key_pair_->GenerateCertificate();
 588   if (local_certificate.empty()) {
 589     LOG(ERROR) << "Failed to generate host certificate.";
 590     ShutdownHost(kInitializationFailed);
 591     return;
 592   }
 593
 594   scoped_refptr<PairingRegistry> pairing_registry = NULL;
 595   if (allow_pairing_) {
 596     if (!pairing_registry_delegate_)
 597       pairing_registry_delegate_ = CreatePairingRegistryDelegate();
 598
 599     if (pairing_registry_delegate_) {
 600       pairing_registry = new PairingRegistry(context_->file_task_runner(),
 601                                              pairing_registry_delegate_.Pass());
 602     }
 603   }
 604
 605   scoped_ptr<protocol::AuthenticatorFactory> factory;
 606
 607   if (third_party_auth_config_.is_empty()) {
 608     factory = protocol::Me2MeHostAuthenticatorFactory::CreateWithSharedSecret(
 609         use_service_account_, host_owner_, local_certificate, key_pair_,
 610         host_secret_hash_, pairing_registry);
 611
 612   } else if (third_party_auth_config_.is_valid()) {
 613     scoped_ptr<protocol::TokenValidatorFactory> token_validator_factory(
 614         new TokenValidatorFactoryImpl(
 615             third_party_auth_config_,
 616             key_pair_, context_->url_request_context_getter()));
 617     factory = protocol::Me2MeHostAuthenticatorFactory::CreateWithThirdPartyAuth(
 618         use_service_account_, host_owner_, local_certificate, key_pair_,
 619         token_validator_factory.Pass());
 620
 621   } else {
 622     // TODO(rmsousa): If the policy is bad the host should not go online. It
 623     // should keep running, but not connected, until the policies are fixed.
 624     // Having it show up as online and then reject all clients is misleading.
 625     LOG(ERROR) << "One of the third-party token URLs is empty or invalid. "
 626                << "Host will reject all clients until policies are corrected. "
 627                << "TokenUrl: " << third_party_auth_config_.token_url << ", "
 628                << "TokenValidationUrl: "
 629                << third_party_auth_config_.token_validation_url;
 630     factory = protocol::Me2MeHostAuthenticatorFactory::CreateRejecting();
 631   }
 632
 633 #if defined(OS_POSIX)
 634   // On Linux and Mac, perform a PAM authorization step after authentication.
 635   factory.reset(new PamAuthorizationFactory(factory.Pass()));
 636 #endif
 637   host_->SetAuthenticatorFactory(factory.Pass());
 638
 639   host_->set_pairing_registry(pairing_registry);
 640 }
 641
 642 // IPC::Listener implementation.
 643 bool HostProcess::OnMessageReceived(const IPC::Message& message) {
 644   DCHECK(context_->ui_task_runner()->BelongsToCurrentThread());
 645
 646 #if defined(REMOTING_MULTI_PROCESS)
 647   bool handled = true;
 648   IPC_BEGIN_MESSAGE_MAP(HostProcess, message)
 649     IPC_MESSAGE_HANDLER(ChromotingDaemonMsg_Crash, OnCrash)
 650     IPC_MESSAGE_HANDLER(ChromotingDaemonNetworkMsg_Configuration,
 651                         OnConfigUpdated)
 652     IPC_MESSAGE_HANDLER(ChromotingDaemonNetworkMsg_InitializePairingRegistry,
 653                         OnInitializePairingRegistry)
 654     IPC_MESSAGE_FORWARD(
 655         ChromotingDaemonNetworkMsg_DesktopAttached,
 656         desktop_session_connector_,
 657         DesktopSessionConnector::OnDesktopSessionAgentAttached)
 658     IPC_MESSAGE_FORWARD(ChromotingDaemonNetworkMsg_TerminalDisconnected,
 659                         desktop_session_connector_,
 660                         DesktopSessionConnector::OnTerminalDisconnected)
 661     IPC_MESSAGE_UNHANDLED(handled = false)
 662   IPC_END_MESSAGE_MAP()
 663
 664   CHECK(handled) << "Received unexpected IPC type: " << message.type();
 665   return handled;
 666
 667 #else  // !defined(REMOTING_MULTI_PROCESS)
 668   return false;
 669 #endif  // !defined(REMOTING_MULTI_PROCESS)
 670 }
 671
 672 void HostProcess::OnChannelError() {
 673   DCHECK(context_->ui_task_runner()->BelongsToCurrentThread());
 674
 675   // Shutdown the host if the daemon process disconnects the IPC channel.
 676   context_->network_task_runner()->PostTask(
 677       FROM_HERE,
 678       base::Bind(&HostProcess::ShutdownHost, this, kSuccessExitCode));
 679 }
 680
 681 void HostProcess::StartOnUiThread() {
 682   DCHECK(context_->ui_task_runner()->BelongsToCurrentThread());
 683
 684   if (!InitWithCommandLine(base::CommandLine::ForCurrentProcess())) {
 685     // Shutdown the host if the command line is invalid.
 686     context_->network_task_runner()->PostTask(
 687         FROM_HERE, base::Bind(&HostProcess::ShutdownHost, this,
 688                               kUsageExitCode));
 689     return;
 690   }
 691
 692 #if defined(OS_LINUX)
 693   // If an audio pipe is specific on the command-line then initialize
 694   // AudioCapturerLinux to capture from it.
 695   base::FilePath audio_pipe_name = base::CommandLine::ForCurrentProcess()->
 696       GetSwitchValuePath(kAudioPipeSwitchName);
 697   if (!audio_pipe_name.empty()) {
 698     remoting::AudioCapturerLinux::InitializePipeReader(
 699         context_->audio_task_runner(), audio_pipe_name);
 700   }
 701
 702   base::FilePath gnubby_socket_name = base::CommandLine::ForCurrentProcess()->
 703       GetSwitchValuePath(kAuthSocknameSwitchName);
 704   if (!gnubby_socket_name.empty())
 705     remoting::GnubbyAuthHandler::SetGnubbySocketName(gnubby_socket_name);
 706 #endif  // defined(OS_LINUX)
 707
 708   // Create a desktop environment factory appropriate to the build type &
 709   // platform.
 710 #if defined(OS_WIN)
 711   IpcDesktopEnvironmentFactory* desktop_environment_factory =
 712       new IpcDesktopEnvironmentFactory(
 713           context_->audio_task_runner(),
 714           context_->network_task_runner(),
 715           context_->video_capture_task_runner(),
 716           context_->network_task_runner(),
 717           daemon_channel_.get());
 718   desktop_session_connector_ = desktop_environment_factory;
 719 #else  // !defined(OS_WIN)
 720   DesktopEnvironmentFactory* desktop_environment_factory;
 721   if (enable_window_capture_) {
 722     desktop_environment_factory =
 723       new SingleWindowDesktopEnvironmentFactory(
 724           context_->network_task_runner(),
 725           context_->input_task_runner(),
 726           context_->ui_task_runner(),
 727           window_id_);
 728   } else {
 729     desktop_environment_factory =
 730       new Me2MeDesktopEnvironmentFactory(
 731           context_->network_task_runner(),
 732           context_->input_task_runner(),
 733           context_->ui_task_runner());
 734   }
 735 #endif  // !defined(OS_WIN)
 736
 737   desktop_environment_factory_.reset(desktop_environment_factory);
 738   desktop_environment_factory_->SetEnableGnubbyAuth(enable_gnubby_auth_);
 739
 740   context_->network_task_runner()->PostTask(
 741       FROM_HERE,
 742       base::Bind(&HostProcess::StartOnNetworkThread, this));
 743 }
 744
 745 void HostProcess::ShutdownOnUiThread() {
 746   DCHECK(context_->ui_task_runner()->BelongsToCurrentThread());
 747
 748   // Tear down resources that need to be torn down on the UI thread.
 749   network_change_notifier_.reset();
 750   daemon_channel_.reset();
 751   desktop_environment_factory_.reset();
 752
 753   // It is now safe for the HostProcess to be deleted.
 754   self_ = NULL;
 755
 756 #if defined(OS_LINUX)
 757   // Cause the global AudioPipeReader to be freed, otherwise the audio
 758   // thread will remain in-use and prevent the process from exiting.
 759   // TODO(wez): DesktopEnvironmentFactory should own the pipe reader.
 760   // See crbug.com/161373 and crbug.com/104544.
 761   AudioCapturerLinux::InitializePipeReader(NULL, base::FilePath());
 762 #endif
 763 }
 764
 765 // Overridden from HeartbeatSender::Listener
 766 void HostProcess::OnUnknownHostIdError() {
 767   LOG(ERROR) << "Host ID not found.";
 768   ShutdownHost(kInvalidHostIdExitCode);
 769 }
 770
 771 void HostProcess::OnHeartbeatSuccessful() {
 772   HOST_LOG << "Host ready to receive connections.";
 773 #if defined(OS_POSIX)
 774   if (signal_parent_) {
 775     kill(getppid(), SIGUSR1);
 776     signal_parent_ = false;
 777   }
 778 #endif
 779 }
 780
 781 void HostProcess::OnHostDeleted() {
 782   LOG(ERROR) << "Host was deleted from the directory.";
 783   ShutdownHost(kInvalidHostIdExitCode);
 784 }
 785
 786 void HostProcess::OnInitializePairingRegistry(
 787     IPC::PlatformFileForTransit privileged_key,
 788     IPC::PlatformFileForTransit unprivileged_key) {
 789   DCHECK(!pairing_registry_delegate_);
 790
 791 #if defined(OS_WIN)
 792   // Initialize the pairing registry delegate.
 793   scoped_ptr<PairingRegistryDelegateWin> delegate(
 794       new PairingRegistryDelegateWin());
 795   bool result = delegate->SetRootKeys(
 796       reinterpret_cast<HKEY>(
 797           IPC::PlatformFileForTransitToPlatformFile(privileged_key)),
 798       reinterpret_cast<HKEY>(
 799           IPC::PlatformFileForTransitToPlatformFile(unprivileged_key)));
 800   if (!result)
 801     return;
 802
 803   pairing_registry_delegate_ = delegate.PassAs<PairingRegistry::Delegate>();
 804 #else  // !defined(OS_WIN)
 805   NOTREACHED();
 806 #endif  // !defined(OS_WIN)
 807 }
 808
 809 // Applies the host config, returning true if successful.
 810 bool HostProcess::ApplyConfig(scoped_ptr<JsonHostConfig> config) {
 811   DCHECK(context_->network_task_runner()->BelongsToCurrentThread());
 812
 813   if (!config->GetString(kHostIdConfigPath, &host_id_)) {
 814     LOG(ERROR) << "host_id is not defined in the config.";
 815     return false;
 816   }
 817
 818   std::string key_base64;
 819   if (!config->GetString(kPrivateKeyConfigPath, &key_base64)) {
 820     LOG(ERROR) << "Private key couldn't be read from the config file.";
 821     return false;
 822   }
 823
 824   key_pair_ = RsaKeyPair::FromString(key_base64);
 825   if (!key_pair_.get()) {
 826     LOG(ERROR) << "Invalid private key in the config file.";
 827     return false;
 828   }
 829
 830   std::string host_secret_hash_string;
 831   if (!config->GetString(kHostSecretHashConfigPath,
 832                          &host_secret_hash_string)) {
 833     host_secret_hash_string = "plain:";
 834   }
 835
 836   if (!host_secret_hash_.Parse(host_secret_hash_string)) {
 837     LOG(ERROR) << "Invalid host_secret_hash.";
 838     return false;
 839   }
 840
 841   // Use an XMPP connection to the Talk network for session signalling.
 842   if (!config->GetString(kXmppLoginConfigPath, &xmpp_server_config_.username) ||
 843       !(config->GetString(kXmppAuthTokenConfigPath,
 844                           &xmpp_server_config_.auth_token) ||
 845         config->GetString(kOAuthRefreshTokenConfigPath,
 846                           &oauth_refresh_token_))) {
 847     LOG(ERROR) << "XMPP credentials are not defined in the config.";
 848     return false;
 849   }
 850
 851   if (!oauth_refresh_token_.empty()) {
 852     // SignalingConnector is responsible for getting OAuth token.
 853     xmpp_server_config_.auth_token = "";
 854     xmpp_server_config_.auth_service = "oauth2";
 855   } else if (!config->GetString(kXmppAuthServiceConfigPath,
 856                                 &xmpp_server_config_.auth_service)) {
 857     // For the me2me host, we default to ClientLogin token for chromiumsync
 858     // because earlier versions of the host had no HTTP stack with which to
 859     // request an OAuth2 access token.
 860     xmpp_server_config_.auth_service = kChromotingTokenDefaultServiceName;
 861   }
 862
 863   if (config->GetString(kHostOwnerConfigPath, &host_owner_)) {
 864     // Service account configs have a host_owner, different from the xmpp_login.
 865     use_service_account_ = true;
 866   } else {
 867     // User credential configs only have an xmpp_login, which is also the owner.
 868     host_owner_ = xmpp_server_config_.username;
 869     use_service_account_ = false;
 870   }
 871
 872   // Allow offering of VP9 encoding to be overridden by the command-line.
 873   if (CommandLine::ForCurrentProcess()->HasSwitch(kEnableVp9SwitchName)) {
 874     enable_vp9_ = true;
 875   } else {
 876     config->GetBoolean(kEnableVp9ConfigPath, &enable_vp9_);
 877   }
 878
 879   // Allow the command-line to override the size of the frame recorder buffer.
 880   std::string frame_recorder_buffer_kb;
 881   if (CommandLine::ForCurrentProcess()->HasSwitch(
 882           kFrameRecorderBufferKbName)) {
 883     frame_recorder_buffer_kb =
 884         CommandLine::ForCurrentProcess()->GetSwitchValueASCII(
 885             kFrameRecorderBufferKbName);
 886   } else {
 887     config->GetString(kFrameRecorderBufferKbConfigPath,
 888                       &frame_recorder_buffer_kb);
 889   }
 890   if (!frame_recorder_buffer_kb.empty()) {
 891     int buffer_kb = 0;
 892     if (base::StringToInt(frame_recorder_buffer_kb, &buffer_kb)) {
 893       frame_recorder_buffer_size_ = 1024LL * buffer_kb;
 894     }
 895   }
 896
 897   return true;
 898 }
 899
 900 void HostProcess::OnPolicyUpdate(scoped_ptr<base::DictionaryValue> policies) {
 901   if (!context_->network_task_runner()->BelongsToCurrentThread()) {
 902     context_->network_task_runner()->PostTask(FROM_HERE, base::Bind(
 903         &HostProcess::OnPolicyUpdate, this, base::Passed(&policies)));
 904     return;
 905   }
 906
 907   bool restart_required = false;
 908   restart_required |= OnHostDomainPolicyUpdate(policies.get());
 909   restart_required |= OnCurtainPolicyUpdate(policies.get());
 910   // Note: UsernamePolicyUpdate must run after OnCurtainPolicyUpdate.
 911   restart_required |= OnUsernamePolicyUpdate(policies.get());
 912   restart_required |= OnNatPolicyUpdate(policies.get());
 913   restart_required |= OnRelayPolicyUpdate(policies.get());
 914   restart_required |= OnUdpPortPolicyUpdate(policies.get());
 915   restart_required |= OnHostTalkGadgetPrefixPolicyUpdate(policies.get());
 916   restart_required |= OnHostTokenUrlPolicyUpdate(policies.get());
 917   restart_required |= OnPairingPolicyUpdate(policies.get());
 918   restart_required |= OnGnubbyAuthPolicyUpdate(policies.get());
 919
 920   if (state_ == HOST_INITIALIZING) {
 921     StartHost();
 922   } else if (state_ == HOST_STARTED && restart_required) {
 923     RestartHost();
 924   }
 925 }
 926
 927 void HostProcess::ApplyHostDomainPolicy() {
 928   HOST_LOG << "Policy sets host domain: " << host_domain_;
 929   if (!host_domain_.empty() &&
 930       !EndsWith(host_owner_, std::string("@") + host_domain_, false)) {
 931     LOG(ERROR) << "The host domain does not match the policy.";
 932     ShutdownHost(kInvalidHostDomainExitCode);
 933   }
 934 }
 935
 936 bool HostProcess::OnHostDomainPolicyUpdate(base::DictionaryValue* policies) {
 937   // Returns true if the host has to be restarted after this policy update.
 938   DCHECK(context_->network_task_runner()->BelongsToCurrentThread());
 939
 940   if (!policies->GetString(policy_hack::PolicyWatcher::kHostDomainPolicyName,
 941                           &host_domain_)) {
 942     return false;
 943   }
 944
 945   ApplyHostDomainPolicy();
 946   return false;
 947 }
 948
 949 void HostProcess::ApplyUsernamePolicy() {
 950   if (host_username_match_required_) {
 951     HOST_LOG << "Policy requires host username match.";
 952     std::string username = GetUsername();
 953     bool shutdown = username.empty() ||
 954         !StartsWithASCII(host_owner_, username + std::string("@"),
 955                          false);
 956
 957 #if defined(OS_MACOSX)
 958     // On Mac, we run as root at the login screen, so the username won't match.
 959     // However, there's no need to enforce the policy at the login screen, as
 960     // the client will have to reconnect if a login occurs.
 961     if (shutdown && getuid() == 0) {
 962       shutdown = false;
 963     }
 964 #endif
 965
 966     // Curtain-mode on Windows presents the standard OS login prompt to the user
 967     // for each connection, removing the need for an explicit user-name matching
 968     // check.
 969 #if defined(OS_WIN) && defined(REMOTING_RDP_SESSION)
 970     if (curtain_required_)
 971       return;
 972 #endif  // defined(OS_WIN) && defined(REMOTING_RDP_SESSION)
 973
 974     // Shutdown the host if the username does not match.
 975     if (shutdown) {
 976       LOG(ERROR) << "The host username does not match.";
 977       ShutdownHost(kUsernameMismatchExitCode);
 978     }
 979   } else {
 980     HOST_LOG << "Policy does not require host username match.";
 981   }
 982 }
 983
 984 bool HostProcess::OnUsernamePolicyUpdate(base::DictionaryValue* policies) {
 985   // Returns false: never restart the host after this policy update.
 986   DCHECK(context_->network_task_runner()->BelongsToCurrentThread());
 987
 988   if (!policies->GetBoolean(
 989       policy_hack::PolicyWatcher::kHostMatchUsernamePolicyName,
 990       &host_username_match_required_)) {
 991     return false;
 992   }
 993
 994   ApplyUsernamePolicy();
 995   return false;
 996 }
 997
 998 bool HostProcess::OnNatPolicyUpdate(base::DictionaryValue* policies) {
 999   // Returns true if the host has to be restarted after this policy update.
1000   DCHECK(context_->network_task_runner()->BelongsToCurrentThread());
1001
1002   if (!policies->GetBoolean(policy_hack::PolicyWatcher::kNatPolicyName,
1003                            &allow_nat_traversal_)) {
1004     return false;
1005   }
1006
1007   if (allow_nat_traversal_) {
1008     HOST_LOG << "Policy enables NAT traversal.";
1009   } else {
1010     HOST_LOG << "Policy disables NAT traversal.";
1011   }
1012   return true;
1013 }
1014
1015 bool HostProcess::OnRelayPolicyUpdate(base::DictionaryValue* policies) {
1016   // Returns true if the host has to be restarted after this policy update.
1017   DCHECK(context_->network_task_runner()->BelongsToCurrentThread());
1018
1019   if (!policies->GetBoolean(policy_hack::PolicyWatcher::kRelayPolicyName,
1020                            &allow_relay_)) {
1021     return false;
1022   }
1023
1024   if (allow_relay_) {
1025     HOST_LOG << "Policy enables use of relay server.";
1026   } else {
1027     HOST_LOG << "Policy disables use of relay server.";
1028   }
1029   return true;
1030 }
1031
1032 bool HostProcess::OnUdpPortPolicyUpdate(base::DictionaryValue* policies) {
1033   // Returns true if the host has to be restarted after this policy update.
1034   DCHECK(context_->network_task_runner()->BelongsToCurrentThread());
1035
1036   std::string udp_port_range;
1037   if (!policies->GetString(policy_hack::PolicyWatcher::kUdpPortRangePolicyName,
1038                            &udp_port_range)) {
1039     return false;
1040   }
1041
1042   // Use default values if policy setting is empty or invalid.
1043   int min_udp_port = 0;
1044   int max_udp_port = 0;
1045   if (!udp_port_range.empty() &&
1046       !NetworkSettings::ParsePortRange(udp_port_range, &min_udp_port,
1047                                        &max_udp_port)) {
1048     LOG(WARNING) << "Invalid port range policy: \"" << udp_port_range
1049                  << "\". Using default values.";
1050   }
1051
1052   if (min_udp_port_ != min_udp_port || max_udp_port_ != max_udp_port) {
1053     if (min_udp_port != 0 && max_udp_port != 0) {
1054       HOST_LOG << "Policy restricts UDP port range to [" << min_udp_port
1055                << ", " << max_udp_port << "]";
1056     } else {
1057       HOST_LOG << "Policy does not restrict UDP port range.";
1058     }
1059     min_udp_port_ = min_udp_port;
1060     max_udp_port_ = max_udp_port;
1061     return true;
1062   }
1063   return false;
1064 }
1065
1066 bool HostProcess::OnCurtainPolicyUpdate(base::DictionaryValue* policies) {
1067   // Returns true if the host has to be restarted after this policy update.
1068   DCHECK(context_->network_task_runner()->BelongsToCurrentThread());
1069
1070   if (!policies->GetBoolean(
1071           policy_hack::PolicyWatcher::kHostRequireCurtainPolicyName,
1072           &curtain_required_)) {
1073     return false;
1074   }
1075
1076 #if defined(OS_MACOSX)
1077   if (curtain_required_) {
1078     // When curtain mode is in effect on Mac, the host process runs in the
1079     // user's switched-out session, but launchd will also run an instance at
1080     // the console login screen.  Even if no user is currently logged-on, we
1081     // can't support remote-access to the login screen because the current host
1082     // process model disconnects the client during login, which would leave
1083     // the logged in session un-curtained on the console until they reconnect.
1084     //
1085     // TODO(jamiewalch): Fix this once we have implemented the multi-process
1086     // daemon architecture (crbug.com/134894)
1087     if (getuid() == 0) {
1088       LOG(ERROR) << "Running the host in the console login session is yet not "
1089                     "supported.";
1090       ShutdownHost(kLoginScreenNotSupportedExitCode);
1091       return false;
1092     }
1093   }
1094 #endif
1095
1096   if (curtain_required_) {
1097     HOST_LOG << "Policy requires curtain-mode.";
1098   } else {
1099     HOST_LOG << "Policy does not require curtain-mode.";
1100   }
1101
1102   if (host_)
1103     host_->SetEnableCurtaining(curtain_required_);
1104   return false;
1105 }
1106
1107 bool HostProcess::OnHostTalkGadgetPrefixPolicyUpdate(
1108     base::DictionaryValue* policies) {
1109   // Returns true if the host has to be restarted after this policy update.
1110   DCHECK(context_->network_task_runner()->BelongsToCurrentThread());
1111
1112   if (!policies->GetString(
1113           policy_hack::PolicyWatcher::kHostTalkGadgetPrefixPolicyName,
1114           &talkgadget_prefix_)) {
1115     return false;
1116   }
1117
1118   HOST_LOG << "Policy sets talkgadget prefix: " << talkgadget_prefix_;
1119   return true;
1120 }
1121
1122 bool HostProcess::OnHostTokenUrlPolicyUpdate(base::DictionaryValue* policies) {
1123   // Returns true if the host has to be restarted after this policy update.
1124   DCHECK(context_->network_task_runner()->BelongsToCurrentThread());
1125
1126   bool token_policy_changed = false;
1127   std::string token_url_string;
1128   if (policies->GetString(
1129           policy_hack::PolicyWatcher::kHostTokenUrlPolicyName,
1130           &token_url_string)) {
1131     token_policy_changed = true;
1132     third_party_auth_config_.token_url = GURL(token_url_string);
1133   }
1134   std::string token_validation_url_string;
1135   if (policies->GetString(
1136           policy_hack::PolicyWatcher::kHostTokenValidationUrlPolicyName,
1137           &token_validation_url_string)) {
1138     token_policy_changed = true;
1139     third_party_auth_config_.token_validation_url =
1140         GURL(token_validation_url_string);
1141   }
1142   if (policies->GetString(
1143           policy_hack::PolicyWatcher::kHostTokenValidationCertIssuerPolicyName,
1144           &third_party_auth_config_.token_validation_cert_issuer)) {
1145     token_policy_changed = true;
1146   }
1147
1148   if (token_policy_changed) {
1149     HOST_LOG << "Policy sets third-party token URLs: "
1150              << "TokenUrl: "
1151              << third_party_auth_config_.token_url << ", "
1152              << "TokenValidationUrl: "
1153              << third_party_auth_config_.token_validation_url << ", "
1154              << "TokenValidationCertificateIssuer: "
1155              << third_party_auth_config_.token_validation_cert_issuer;
1156   }
1157   return token_policy_changed;
1158 }
1159
1160 bool HostProcess::OnPairingPolicyUpdate(base::DictionaryValue* policies) {
1161   DCHECK(context_->network_task_runner()->BelongsToCurrentThread());
1162
1163   if (!policies->GetBoolean(
1164           policy_hack::PolicyWatcher::kHostAllowClientPairing,
1165           &allow_pairing_)) {
1166     return false;
1167   }
1168
1169   if (allow_pairing_) {
1170     HOST_LOG << "Policy enables client pairing.";
1171   } else {
1172     HOST_LOG << "Policy disables client pairing.";
1173   }
1174   return true;
1175 }
1176
1177 bool HostProcess::OnGnubbyAuthPolicyUpdate(base::DictionaryValue* policies) {
1178   DCHECK(context_->network_task_runner()->BelongsToCurrentThread());
1179
1180   if (!policies->GetBoolean(
1181           policy_hack::PolicyWatcher::kHostAllowGnubbyAuthPolicyName,
1182           &enable_gnubby_auth_)) {
1183     return false;
1184   }
1185
1186   if (enable_gnubby_auth_) {
1187     HOST_LOG << "Policy enables gnubby auth.";
1188   } else {
1189     HOST_LOG << "Policy disables gnubby auth.";
1190   }
1191
1192   if (desktop_environment_factory_)
1193     desktop_environment_factory_->SetEnableGnubbyAuth(enable_gnubby_auth_);
1194
1195   return true;
1196 }
1197
1198 void HostProcess::StartHost() {
1199   DCHECK(context_->network_task_runner()->BelongsToCurrentThread());
1200   DCHECK(!host_);
1201   DCHECK(!signal_strategy_.get());
1202   DCHECK(state_ == HOST_INITIALIZING || state_ == HOST_STOPPING_TO_RESTART ||
1203          state_ == HOST_STOPPED) << state_;
1204   state_ = HOST_STARTED;
1205
1206   signal_strategy_.reset(
1207       new XmppSignalStrategy(net::ClientSocketFactory::GetDefaultFactory(),
1208                              context_->url_request_context_getter(),
1209                              xmpp_server_config_));
1210
1211   scoped_ptr<DnsBlackholeChecker> dns_blackhole_checker(
1212       new DnsBlackholeChecker(context_->url_request_context_getter(),
1213                               talkgadget_prefix_));
1214
1215   // Create a NetworkChangeNotifier for use by the signaling connector.
1216   network_change_notifier_.reset(net::NetworkChangeNotifier::Create());
1217
1218   signaling_connector_.reset(new SignalingConnector(
1219       signal_strategy_.get(),
1220       dns_blackhole_checker.Pass(),
1221       base::Bind(&HostProcess::OnAuthFailed, this)));
1222
1223   if (!oauth_refresh_token_.empty()) {
1224     scoped_ptr<OAuthTokenGetter::OAuthCredentials> oauth_credentials;
1225     oauth_credentials.reset(
1226         new OAuthTokenGetter::OAuthCredentials(
1227             xmpp_server_config_.username, oauth_refresh_token_,
1228             use_service_account_));
1229
1230     oauth_token_getter_.reset(new OAuthTokenGetter(
1231         oauth_credentials.Pass(), context_->url_request_context_getter(),
1232         false));
1233
1234     signaling_connector_->EnableOAuth(oauth_token_getter_.get());
1235   }
1236
1237   uint32 network_flags = 0;
1238   if (allow_nat_traversal_) {
1239     network_flags = NetworkSettings::NAT_TRAVERSAL_STUN |
1240                     NetworkSettings::NAT_TRAVERSAL_OUTGOING;
1241     if (allow_relay_)
1242       network_flags |= NetworkSettings::NAT_TRAVERSAL_RELAY;
1243   }
1244
1245   NetworkSettings network_settings(network_flags);
1246
1247   if (min_udp_port_ && max_udp_port_) {
1248     network_settings.min_port = min_udp_port_;
1249     network_settings.max_port = max_udp_port_;
1250   } else if (!allow_nat_traversal_) {
1251     // For legacy reasons we have to restrict the port range to a set of default
1252     // values when nat traversal is disabled, even if the port range was not
1253     // set in policy.
1254     network_settings.min_port = NetworkSettings::kDefaultMinPort;
1255     network_settings.max_port = NetworkSettings::kDefaultMaxPort;
1256   }
1257
1258   host_.reset(new ChromotingHost(
1259       signal_strategy_.get(),
1260       desktop_environment_factory_.get(),
1261       CreateHostSessionManager(signal_strategy_.get(), network_settings,
1262                                context_->url_request_context_getter()),
1263       context_->audio_task_runner(),
1264       context_->input_task_runner(),
1265       context_->video_capture_task_runner(),
1266       context_->video_encode_task_runner(),
1267       context_->network_task_runner(),
1268       context_->ui_task_runner()));
1269
1270   if (enable_vp9_) {
1271     scoped_ptr<protocol::CandidateSessionConfig> config =
1272         host_->protocol_config()->Clone();
1273     config->EnableVideoCodec(protocol::ChannelConfig::CODEC_VP9);
1274     host_->set_protocol_config(config.Pass());
1275   }
1276
1277   if (frame_recorder_buffer_size_ > 0) {
1278     scoped_ptr<VideoFrameRecorderHostExtension> frame_recorder_extension(
1279         new VideoFrameRecorderHostExtension());
1280     frame_recorder_extension->SetMaxContentBytes(frame_recorder_buffer_size_);
1281     host_->AddExtension(frame_recorder_extension.PassAs<HostExtension>());
1282   }
1283
1284   // TODO(simonmorris): Get the maximum session duration from a policy.
1285 #if defined(OS_LINUX)
1286   host_->SetMaximumSessionDuration(base::TimeDelta::FromHours(20));
1287 #endif
1288
1289   heartbeat_sender_.reset(new HeartbeatSender(
1290       this, host_id_, signal_strategy_.get(), key_pair_,
1291       directory_bot_jid_));
1292
1293   host_status_sender_.reset(new HostStatusSender(
1294       host_id_, signal_strategy_.get(), key_pair_, directory_bot_jid_));
1295
1296   host_change_notification_listener_.reset(new HostChangeNotificationListener(
1297       this, host_id_, signal_strategy_.get(), directory_bot_jid_));
1298
1299   host_status_logger_.reset(
1300       new HostStatusLogger(host_->AsWeakPtr(), ServerLogEntry::ME2ME,
1301                            signal_strategy_.get(), directory_bot_jid_));
1302
1303   // Set up reporting the host status notifications.
1304 #if defined(REMOTING_MULTI_PROCESS)
1305   host_event_logger_.reset(
1306       new IpcHostEventLogger(host_->AsWeakPtr(), daemon_channel_.get()));
1307 #else  // !defined(REMOTING_MULTI_PROCESS)
1308   host_event_logger_ =
1309       HostEventLogger::Create(host_->AsWeakPtr(), kApplicationName);
1310 #endif  // !defined(REMOTING_MULTI_PROCESS)
1311
1312   host_->SetEnableCurtaining(curtain_required_);
1313   host_->Start(host_owner_);
1314
1315   CreateAuthenticatorFactory();
1316 }
1317
1318 void HostProcess::OnAuthFailed() {
1319   ShutdownHost(kInvalidOauthCredentialsExitCode);
1320 }
1321
1322 void HostProcess::RestartHost() {
1323   DCHECK(context_->network_task_runner()->BelongsToCurrentThread());
1324   DCHECK_EQ(state_, HOST_STARTED);
1325
1326   state_ = HOST_STOPPING_TO_RESTART;
1327   ShutdownOnNetworkThread();
1328 }
1329
1330 void HostProcess::ShutdownHost(HostExitCodes exit_code) {
1331   DCHECK(context_->network_task_runner()->BelongsToCurrentThread());
1332
1333   *exit_code_out_ = exit_code;
1334
1335   switch (state_) {
1336     case HOST_INITIALIZING:
1337       state_ = HOST_STOPPING;
1338       ShutdownOnNetworkThread();
1339       break;
1340
1341     case HOST_STARTED:
1342       state_ = HOST_STOPPING;
1343       host_status_sender_->SendOfflineStatus(exit_code);
1344       ScheduleHostShutdown();
1345       break;
1346
1347     case HOST_STOPPING_TO_RESTART:
1348       state_ = HOST_STOPPING;
1349       break;
1350
1351     case HOST_STOPPING:
1352     case HOST_STOPPED:
1353       // Host is already stopped or being stopped. No action is required.
1354       break;
1355   }
1356 }
1357
1358 // TODO(weitaosu): shut down the host once we get an ACK for the offline status
1359 //                  XMPP message.
1360 void HostProcess::ScheduleHostShutdown() {
1361   // Delay the shutdown by 2 second to allow SendOfflineStatus to complete.
1362   context_->network_task_runner()->PostDelayedTask(
1363       FROM_HERE,
1364       base::Bind(&HostProcess::ShutdownOnNetworkThread, base::Unretained(this)),
1365       base::TimeDelta::FromSeconds(2));
1366 }
1367
1368 void HostProcess::ShutdownOnNetworkThread() {
1369   DCHECK(context_->network_task_runner()->BelongsToCurrentThread());
1370
1371   host_.reset();
1372   host_event_logger_.reset();
1373   host_status_logger_.reset();
1374   heartbeat_sender_.reset();
1375   host_status_sender_.reset();
1376   host_change_notification_listener_.reset();
1377   signaling_connector_.reset();
1378   oauth_token_getter_.reset();
1379   signal_strategy_.reset();
1380   network_change_notifier_.reset();
1381
1382   if (state_ == HOST_STOPPING_TO_RESTART) {
1383     StartHost();
1384   } else if (state_ == HOST_STOPPING) {
1385     state_ = HOST_STOPPED;
1386
1387     if (policy_watcher_.get()) {
1388       base::WaitableEvent done_event(true, false);
1389       policy_watcher_->StopWatching(&done_event);
1390       done_event.Wait();
1391       policy_watcher_.reset();
1392     }
1393
1394     config_watcher_.reset();
1395
1396     // Complete the rest of shutdown on the main thread.
1397     context_->ui_task_runner()->PostTask(
1398         FROM_HERE,
1399         base::Bind(&HostProcess::ShutdownOnUiThread, this));
1400   } else {
1401     // This method is only called in STOPPING_TO_RESTART and STOPPING states.
1402     NOTREACHED();
1403   }
1404 }
1405
1406 void HostProcess::OnCrash(const std::string& function_name,
1407                           const std::string& file_name,
1408                           const int& line_number) {
1409   char message[1024];
1410   base::snprintf(message, sizeof(message),
1411                  "Requested by %s at %s, line %d.",
1412                  function_name.c_str(), file_name.c_str(), line_number);
1413   base::debug::Alias(message);
1414
1415   // The daemon requested us to crash the process.
1416   CHECK(false) << message;
1417 }
1418
1419 int HostProcessMain() {
1420 #if defined(OS_LINUX)
1421   // Required in order for us to run multiple X11 threads.
1422   XInitThreads();
1423
1424   // Required for any calls into GTK functions, such as the Disconnect and
1425   // Continue windows, though these should not be used for the Me2Me case
1426   // (crbug.com/104377).
1427   gtk_init(NULL, NULL);
1428 #endif
1429
1430   // Enable support for SSL server sockets, which must be done while still
1431   // single-threaded.
1432   net::EnableSSLServerSockets();
1433
1434   // Ensures runtime specific CPU features are initialized.
1435   media::InitializeCPUSpecificMediaFeatures();
1436
1437   // Create the main message loop and start helper threads.
1438   base::MessageLoopForUI message_loop;
1439   scoped_ptr<ChromotingHostContext> context =
1440       ChromotingHostContext::Create(new AutoThreadTaskRunner(
1441           message_loop.message_loop_proxy(), base::MessageLoop::QuitClosure()));
1442   if (!context)
1443     return kInitializationFailed;
1444
1445   // Create & start the HostProcess using these threads.
1446   // TODO(wez): The HostProcess holds a reference to itself until Shutdown().
1447   // Remove this hack as part of the multi-process refactoring.
1448   int exit_code = kSuccessExitCode;
1449   new HostProcess(context.Pass(), &exit_code);
1450
1451   // Run the main (also UI) message loop until the host no longer needs it.
1452   message_loop.Run();
1453
1454   return exit_code;
1455 }
1456
1457 }  // namespace remoting