remoting/host/chromoting_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 #include "remoting/host/chromoting_host.h"
   6
   7 #include <algorithm>
   8
   9 #include "base/bind.h"
  10 #include "base/callback.h"
  11 #include "base/message_loop/message_loop_proxy.h"
  12 #include "build/build_config.h"
  13 #include "remoting/base/constants.h"
  14 #include "remoting/base/logging.h"
  15 #include "remoting/host/chromoting_host_context.h"
  16 #include "remoting/host/desktop_environment.h"
  17 #include "remoting/host/host_config.h"
  18 #include "remoting/host/input_injector.h"
  19 #include "remoting/protocol/connection_to_client.h"
  20 #include "remoting/protocol/client_stub.h"
  21 #include "remoting/protocol/host_stub.h"
  22 #include "remoting/protocol/input_stub.h"
  23 #include "remoting/protocol/session_config.h"
  24
  25 using remoting::protocol::ConnectionToClient;
  26 using remoting::protocol::InputStub;
  27
  28 namespace remoting {
  29
  30 namespace {
  31
  32 const net::BackoffEntry::Policy kDefaultBackoffPolicy = {
  33   // Number of initial errors (in sequence) to ignore before applying
  34   // exponential back-off rules.
  35   0,
  36
  37   // Initial delay for exponential back-off in ms.
  38   2000,
  39
  40   // Factor by which the waiting time will be multiplied.
  41   2,
  42
  43   // Fuzzing percentage. ex: 10% will spread requests randomly
  44   // between 90%-100% of the calculated time.
  45   0,
  46
  47   // Maximum amount of time we are willing to delay our request in ms.
  48   -1,
  49
  50   // Time to keep an entry from being discarded even when it
  51   // has no significant state, -1 to never discard.
  52   -1,
  53
  54   // Don't use initial delay unless the last request was an error.
  55   false,
  56 };
  57
  58 }  // namespace
  59
  60 ChromotingHost::ChromotingHost(
  61     SignalStrategy* signal_strategy,
  62     DesktopEnvironmentFactory* desktop_environment_factory,
  63     scoped_ptr<protocol::SessionManager> session_manager,
  64     scoped_refptr<base::SingleThreadTaskRunner> audio_task_runner,
  65     scoped_refptr<base::SingleThreadTaskRunner> input_task_runner,
  66     scoped_refptr<base::SingleThreadTaskRunner> video_capture_task_runner,
  67     scoped_refptr<base::SingleThreadTaskRunner> video_encode_task_runner,
  68     scoped_refptr<base::SingleThreadTaskRunner> network_task_runner,
  69     scoped_refptr<base::SingleThreadTaskRunner> ui_task_runner)
  70     : desktop_environment_factory_(desktop_environment_factory),
  71       session_manager_(session_manager.Pass()),
  72       audio_task_runner_(audio_task_runner),
  73       input_task_runner_(input_task_runner),
  74       video_capture_task_runner_(video_capture_task_runner),
  75       video_encode_task_runner_(video_encode_task_runner),
  76       network_task_runner_(network_task_runner),
  77       ui_task_runner_(ui_task_runner),
  78       signal_strategy_(signal_strategy),
  79       started_(false),
  80       protocol_config_(protocol::CandidateSessionConfig::CreateDefault()),
  81       login_backoff_(&kDefaultBackoffPolicy),
  82       authenticating_client_(false),
  83       reject_authenticating_client_(false),
  84       enable_curtaining_(false),
  85       weak_factory_(this) {
  86   DCHECK(network_task_runner_->BelongsToCurrentThread());
  87   DCHECK(signal_strategy);
  88
  89   // VP9 encode is not yet supported.
  90   protocol::CandidateSessionConfig::DisableVideoCodec(
  91       protocol_config_.get(), protocol::ChannelConfig::CODEC_VP9);
  92
  93   if (!desktop_environment_factory_->SupportsAudioCapture()) {
  94     protocol::CandidateSessionConfig::DisableAudioChannel(
  95         protocol_config_.get());
  96   }
  97 }
  98
  99 ChromotingHost::~ChromotingHost() {
 100   DCHECK(CalledOnValidThread());
 101
 102   // Disconnect all of the clients.
 103   while (!clients_.empty()) {
 104     clients_.front()->DisconnectSession();
 105   }
 106
 107   // Destroy the session manager to make sure that |signal_strategy_| does not
 108   // have any listeners registered.
 109   session_manager_.reset();
 110
 111   // Notify observers.
 112   if (started_)
 113     FOR_EACH_OBSERVER(HostStatusObserver, status_observers_, OnShutdown());
 114 }
 115
 116 void ChromotingHost::Start(const std::string& host_owner) {
 117   DCHECK(CalledOnValidThread());
 118   DCHECK(!started_);
 119
 120   HOST_LOG << "Starting host";
 121   started_ = true;
 122   FOR_EACH_OBSERVER(HostStatusObserver, status_observers_, OnStart(host_owner));
 123
 124   // Start the SessionManager, supplying this ChromotingHost as the listener.
 125   session_manager_->Init(signal_strategy_, this);
 126 }
 127
 128 void ChromotingHost::AddStatusObserver(HostStatusObserver* observer) {
 129   DCHECK(CalledOnValidThread());
 130   status_observers_.AddObserver(observer);
 131 }
 132
 133 void ChromotingHost::RemoveStatusObserver(HostStatusObserver* observer) {
 134   DCHECK(CalledOnValidThread());
 135   status_observers_.RemoveObserver(observer);
 136 }
 137
 138 void ChromotingHost::RejectAuthenticatingClient() {
 139   DCHECK(authenticating_client_);
 140   reject_authenticating_client_ = true;
 141 }
 142
 143 void ChromotingHost::SetAuthenticatorFactory(
 144     scoped_ptr<protocol::AuthenticatorFactory> authenticator_factory) {
 145   DCHECK(CalledOnValidThread());
 146   session_manager_->set_authenticator_factory(authenticator_factory.Pass());
 147 }
 148
 149 void ChromotingHost::SetEnableCurtaining(bool enable) {
 150   DCHECK(network_task_runner_->BelongsToCurrentThread());
 151
 152   if (enable_curtaining_ == enable)
 153     return;
 154
 155   enable_curtaining_ = enable;
 156   desktop_environment_factory_->SetEnableCurtaining(enable_curtaining_);
 157
 158   // Disconnect all existing clients because they might be running not
 159   // curtained.
 160   // TODO(alexeypa): fix this such that the curtain is applied to the not
 161   // curtained sessions or disconnect only the client connected to not
 162   // curtained sessions.
 163   if (enable_curtaining_)
 164     DisconnectAllClients();
 165 }
 166
 167 void ChromotingHost::SetMaximumSessionDuration(
 168     const base::TimeDelta& max_session_duration) {
 169   max_session_duration_ = max_session_duration;
 170 }
 171
 172 ////////////////////////////////////////////////////////////////////////////
 173 // protocol::ClientSession::EventHandler implementation.
 174 void ChromotingHost::OnSessionAuthenticating(ClientSession* client) {
 175   // We treat each incoming connection as a failure to authenticate,
 176   // and clear the backoff when a connection successfully
 177   // authenticates. This allows the backoff to protect from parallel
 178   // connection attempts as well as sequential ones.
 179   if (login_backoff_.ShouldRejectRequest()) {
 180     LOG(WARNING) << "Disconnecting client " << client->client_jid() << " due to"
 181                     " an overload of failed login attempts.";
 182     client->DisconnectSession();
 183     return;
 184   }
 185   login_backoff_.InformOfRequest(false);
 186 }
 187
 188 bool ChromotingHost::OnSessionAuthenticated(ClientSession* client) {
 189   DCHECK(CalledOnValidThread());
 190
 191   login_backoff_.Reset();
 192
 193   // Disconnect all other clients. |it| should be advanced before Disconnect()
 194   // is called to avoid it becoming invalid when the client is removed from
 195   // the list.
 196   ClientList::iterator it = clients_.begin();
 197   while (it != clients_.end()) {
 198     ClientSession* other_client = *it++;
 199     if (other_client != client)
 200       other_client->DisconnectSession();
 201   }
 202
 203   // Disconnects above must have destroyed all other clients.
 204   DCHECK_EQ(clients_.size(), 1U);
 205
 206   // Notify observers that there is at least one authenticated client.
 207   const std::string& jid = client->client_jid();
 208
 209   reject_authenticating_client_ = false;
 210
 211   authenticating_client_ = true;
 212   FOR_EACH_OBSERVER(HostStatusObserver, status_observers_,
 213                     OnClientAuthenticated(jid));
 214   authenticating_client_ = false;
 215
 216   return !reject_authenticating_client_;
 217 }
 218
 219 void ChromotingHost::OnSessionChannelsConnected(ClientSession* client) {
 220   DCHECK(CalledOnValidThread());
 221
 222   // Notify observers.
 223   FOR_EACH_OBSERVER(HostStatusObserver, status_observers_,
 224                     OnClientConnected(client->client_jid()));
 225 }
 226
 227 void ChromotingHost::OnSessionAuthenticationFailed(ClientSession* client) {
 228   DCHECK(CalledOnValidThread());
 229
 230   // Notify observers.
 231   FOR_EACH_OBSERVER(HostStatusObserver, status_observers_,
 232                     OnAccessDenied(client->client_jid()));
 233 }
 234
 235 void ChromotingHost::OnSessionClosed(ClientSession* client) {
 236   DCHECK(CalledOnValidThread());
 237
 238   ClientList::iterator it = std::find(clients_.begin(), clients_.end(), client);
 239   CHECK(it != clients_.end());
 240
 241   if (client->is_authenticated()) {
 242     FOR_EACH_OBSERVER(HostStatusObserver, status_observers_,
 243                       OnClientDisconnected(client->client_jid()));
 244   }
 245
 246   clients_.erase(it);
 247   delete client;
 248 }
 249
 250 void ChromotingHost::OnSessionSequenceNumber(ClientSession* session,
 251                                              int64 sequence_number) {
 252   DCHECK(CalledOnValidThread());
 253 }
 254
 255 void ChromotingHost::OnSessionRouteChange(
 256     ClientSession* session,
 257     const std::string& channel_name,
 258     const protocol::TransportRoute& route) {
 259   DCHECK(CalledOnValidThread());
 260   FOR_EACH_OBSERVER(HostStatusObserver, status_observers_,
 261                     OnClientRouteChange(session->client_jid(), channel_name,
 262                                         route));
 263 }
 264
 265 void ChromotingHost::OnSessionManagerReady() {
 266   DCHECK(CalledOnValidThread());
 267   // Don't need to do anything here, just wait for incoming
 268   // connections.
 269 }
 270
 271 void ChromotingHost::OnIncomingSession(
 272       protocol::Session* session,
 273       protocol::SessionManager::IncomingSessionResponse* response) {
 274   DCHECK(CalledOnValidThread());
 275
 276   if (!started_) {
 277     *response = protocol::SessionManager::DECLINE;
 278     return;
 279   }
 280
 281   if (login_backoff_.ShouldRejectRequest()) {
 282     LOG(WARNING) << "Rejecting connection due to"
 283                     " an overload of failed login attempts.";
 284     *response = protocol::SessionManager::OVERLOAD;
 285     return;
 286   }
 287
 288   protocol::SessionConfig config;
 289   if (!protocol_config_->Select(session->candidate_config(), &config)) {
 290     LOG(WARNING) << "Rejecting connection from " << session->jid()
 291                  << " because no compatible configuration has been found.";
 292     *response = protocol::SessionManager::INCOMPATIBLE;
 293     return;
 294   }
 295
 296   session->set_config(config);
 297
 298   *response = protocol::SessionManager::ACCEPT;
 299
 300   HOST_LOG << "Client connected: " << session->jid();
 301
 302   // Create a client object.
 303   scoped_ptr<protocol::ConnectionToClient> connection(
 304       new protocol::ConnectionToClient(session));
 305   ClientSession* client = new ClientSession(
 306       this,
 307       audio_task_runner_,
 308       input_task_runner_,
 309       video_capture_task_runner_,
 310       video_encode_task_runner_,
 311       network_task_runner_,
 312       ui_task_runner_,
 313       connection.Pass(),
 314       desktop_environment_factory_,
 315       max_session_duration_,
 316       pairing_registry_);
 317   clients_.push_back(client);
 318 }
 319
 320 void ChromotingHost::set_protocol_config(
 321     scoped_ptr<protocol::CandidateSessionConfig> config) {
 322   DCHECK(CalledOnValidThread());
 323   DCHECK(config.get());
 324   DCHECK(!started_);
 325   protocol_config_ = config.Pass();
 326 }
 327
 328 void ChromotingHost::DisconnectAllClients() {
 329   DCHECK(CalledOnValidThread());
 330
 331   while (!clients_.empty()) {
 332     size_t size = clients_.size();
 333     clients_.front()->DisconnectSession();
 334     CHECK_EQ(clients_.size(), size - 1);
 335   }
 336 }
 337
 338 }  // namespace remoting