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/command_line.h"
  12 #include "build/build_config.h"
  13 #include "jingle/glue/thread_wrapper.h"
  14 #include "remoting/base/constants.h"
  15 #include "remoting/base/logging.h"
  16 #include "remoting/host/chromoting_host_context.h"
  17 #include "remoting/host/desktop_environment.h"
  18 #include "remoting/host/host_config.h"
  19 #include "remoting/host/input_injector.h"
  20 #include "remoting/host/video_frame_recorder.h"
  21 #include "remoting/protocol/connection_to_client.h"
  22 #include "remoting/protocol/client_stub.h"
  23 #include "remoting/protocol/host_stub.h"
  24 #include "remoting/protocol/input_stub.h"
  25 #include "remoting/protocol/session_config.h"
  26
  27 using remoting::protocol::ConnectionToClient;
  28 using remoting::protocol::InputStub;
  29
  30 namespace remoting {
  31
  32 namespace {
  33
  34 const net::BackoffEntry::Policy kDefaultBackoffPolicy = {
  35   // Number of initial errors (in sequence) to ignore before applying
  36   // exponential back-off rules.
  37   0,
  38
  39   // Initial delay for exponential back-off in ms.
  40   2000,
  41
  42   // Factor by which the waiting time will be multiplied.
  43   2,
  44
  45   // Fuzzing percentage. ex: 10% will spread requests randomly
  46   // between 90%-100% of the calculated time.
  47   0,
  48
  49   // Maximum amount of time we are willing to delay our request in ms.
  50   -1,
  51
  52   // Time to keep an entry from being discarded even when it
  53   // has no significant state, -1 to never discard.
  54   -1,
  55
  56   // Don't use initial delay unless the last request was an error.
  57   false,
  58 };
  59
  60 }  // namespace
  61
  62 ChromotingHost::ChromotingHost(
  63     SignalStrategy* signal_strategy,
  64     DesktopEnvironmentFactory* desktop_environment_factory,
  65     scoped_ptr<protocol::SessionManager> session_manager,
  66     scoped_refptr<base::SingleThreadTaskRunner> audio_task_runner,
  67     scoped_refptr<base::SingleThreadTaskRunner> input_task_runner,
  68     scoped_refptr<base::SingleThreadTaskRunner> video_capture_task_runner,
  69     scoped_refptr<base::SingleThreadTaskRunner> video_encode_task_runner,
  70     scoped_refptr<base::SingleThreadTaskRunner> network_task_runner,
  71     scoped_refptr<base::SingleThreadTaskRunner> ui_task_runner)
  72     : desktop_environment_factory_(desktop_environment_factory),
  73       session_manager_(session_manager.Pass()),
  74       audio_task_runner_(audio_task_runner),
  75       input_task_runner_(input_task_runner),
  76       video_capture_task_runner_(video_capture_task_runner),
  77       video_encode_task_runner_(video_encode_task_runner),
  78       network_task_runner_(network_task_runner),
  79       ui_task_runner_(ui_task_runner),
  80       signal_strategy_(signal_strategy),
  81       started_(false),
  82       protocol_config_(protocol::CandidateSessionConfig::CreateDefault()),
  83       login_backoff_(&kDefaultBackoffPolicy),
  84       authenticating_client_(false),
  85       reject_authenticating_client_(false),
  86       enable_curtaining_(false),
  87       weak_factory_(this) {
  88   DCHECK(network_task_runner_->BelongsToCurrentThread());
  89   DCHECK(signal_strategy);
  90
  91   jingle_glue::JingleThreadWrapper::EnsureForCurrentMessageLoop();
  92
  93   if (!desktop_environment_factory_->SupportsAudioCapture()) {
  94     protocol_config_->DisableAudioChannel();
  95   }
  96 }
  97
  98 ChromotingHost::~ChromotingHost() {
  99   DCHECK(CalledOnValidThread());
 100
 101   // Disconnect all of the clients.
 102   while (!clients_.empty()) {
 103     clients_.front()->DisconnectSession();
 104   }
 105
 106   // Destroy the session manager to make sure that |signal_strategy_| does not
 107   // have any listeners registered.
 108   session_manager_.reset();
 109
 110   // Notify observers.
 111   if (started_)
 112     FOR_EACH_OBSERVER(HostStatusObserver, status_observers_, OnShutdown());
 113 }
 114
 115 void ChromotingHost::Start(const std::string& host_owner_email) {
 116   DCHECK(CalledOnValidThread());
 117   DCHECK(!started_);
 118
 119   HOST_LOG << "Starting host";
 120   started_ = true;
 121   FOR_EACH_OBSERVER(HostStatusObserver, status_observers_,
 122                     OnStart(host_owner_email));
 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::AddExtension(scoped_ptr<HostExtension> extension) {
 139   extensions_.push_back(extension.release());
 140 }
 141
 142 void ChromotingHost::RejectAuthenticatingClient() {
 143   DCHECK(authenticating_client_);
 144   reject_authenticating_client_ = true;
 145 }
 146
 147 void ChromotingHost::SetAuthenticatorFactory(
 148     scoped_ptr<protocol::AuthenticatorFactory> authenticator_factory) {
 149   DCHECK(CalledOnValidThread());
 150   session_manager_->set_authenticator_factory(authenticator_factory.Pass());
 151 }
 152
 153 void ChromotingHost::SetEnableCurtaining(bool enable) {
 154   DCHECK(network_task_runner_->BelongsToCurrentThread());
 155
 156   if (enable_curtaining_ == enable)
 157     return;
 158
 159   enable_curtaining_ = enable;
 160   desktop_environment_factory_->SetEnableCurtaining(enable_curtaining_);
 161
 162   // Disconnect all existing clients because they might be running not
 163   // curtained.
 164   // TODO(alexeypa): fix this such that the curtain is applied to the not
 165   // curtained sessions or disconnect only the client connected to not
 166   // curtained sessions.
 167   if (enable_curtaining_)
 168     DisconnectAllClients();
 169 }
 170
 171 void ChromotingHost::SetMaximumSessionDuration(
 172     const base::TimeDelta& max_session_duration) {
 173   max_session_duration_ = max_session_duration;
 174 }
 175
 176 ////////////////////////////////////////////////////////////////////////////
 177 // protocol::ClientSession::EventHandler implementation.
 178 void ChromotingHost::OnSessionAuthenticating(ClientSession* client) {
 179   // We treat each incoming connection as a failure to authenticate,
 180   // and clear the backoff when a connection successfully
 181   // authenticates. This allows the backoff to protect from parallel
 182   // connection attempts as well as sequential ones.
 183   if (login_backoff_.ShouldRejectRequest()) {
 184     LOG(WARNING) << "Disconnecting client " << client->client_jid() << " due to"
 185                     " an overload of failed login attempts.";
 186     client->DisconnectSession();
 187     return;
 188   }
 189   login_backoff_.InformOfRequest(false);
 190 }
 191
 192 bool ChromotingHost::OnSessionAuthenticated(ClientSession* client) {
 193   DCHECK(CalledOnValidThread());
 194
 195   login_backoff_.Reset();
 196
 197   // Disconnect all other clients. |it| should be advanced before Disconnect()
 198   // is called to avoid it becoming invalid when the client is removed from
 199   // the list.
 200   ClientList::iterator it = clients_.begin();
 201   while (it != clients_.end()) {
 202     ClientSession* other_client = *it++;
 203     if (other_client != client)
 204       other_client->DisconnectSession();
 205   }
 206
 207   // Disconnects above must have destroyed all other clients.
 208   DCHECK_EQ(clients_.size(), 1U);
 209
 210   // Notify observers that there is at least one authenticated client.
 211   const std::string& jid = client->client_jid();
 212
 213   reject_authenticating_client_ = false;
 214
 215   authenticating_client_ = true;
 216   FOR_EACH_OBSERVER(HostStatusObserver, status_observers_,
 217                     OnClientAuthenticated(jid));
 218   authenticating_client_ = false;
 219
 220   return !reject_authenticating_client_;
 221 }
 222
 223 void ChromotingHost::OnSessionChannelsConnected(ClientSession* client) {
 224   DCHECK(CalledOnValidThread());
 225
 226   // Notify observers.
 227   FOR_EACH_OBSERVER(HostStatusObserver, status_observers_,
 228                     OnClientConnected(client->client_jid()));
 229 }
 230
 231 void ChromotingHost::OnSessionAuthenticationFailed(ClientSession* client) {
 232   DCHECK(CalledOnValidThread());
 233
 234   // Notify observers.
 235   FOR_EACH_OBSERVER(HostStatusObserver, status_observers_,
 236                     OnAccessDenied(client->client_jid()));
 237 }
 238
 239 void ChromotingHost::OnSessionClosed(ClientSession* client) {
 240   DCHECK(CalledOnValidThread());
 241
 242   ClientList::iterator it = std::find(clients_.begin(), clients_.end(), client);
 243   CHECK(it != clients_.end());
 244
 245   if (client->is_authenticated()) {
 246     FOR_EACH_OBSERVER(HostStatusObserver, status_observers_,
 247                       OnClientDisconnected(client->client_jid()));
 248   }
 249
 250   clients_.erase(it);
 251   delete client;
 252 }
 253
 254 void ChromotingHost::OnSessionRouteChange(
 255     ClientSession* session,
 256     const std::string& channel_name,
 257     const protocol::TransportRoute& route) {
 258   DCHECK(CalledOnValidThread());
 259   FOR_EACH_OBSERVER(HostStatusObserver, status_observers_,
 260                     OnClientRouteChange(session->client_jid(), channel_name,
 261                                         route));
 262 }
 263
 264 void ChromotingHost::OnSessionManagerReady() {
 265   DCHECK(CalledOnValidThread());
 266   // Don't need to do anything here, just wait for incoming
 267   // connections.
 268 }
 269
 270 void ChromotingHost::OnIncomingSession(
 271       protocol::Session* session,
 272       protocol::SessionManager::IncomingSessionResponse* response) {
 273   DCHECK(CalledOnValidThread());
 274
 275   if (!started_) {
 276     *response = protocol::SessionManager::DECLINE;
 277     return;
 278   }
 279
 280   if (login_backoff_.ShouldRejectRequest()) {
 281     LOG(WARNING) << "Rejecting connection due to"
 282                     " an overload of failed login attempts.";
 283     *response = protocol::SessionManager::OVERLOAD;
 284     return;
 285   }
 286
 287   scoped_ptr<protocol::SessionConfig> config =
 288       protocol::SessionConfig::SelectCommon(session->candidate_config(),
 289                                             protocol_config_.get());
 290   if (!config) {
 291     LOG(WARNING) << "Rejecting connection from " << session->jid()
 292                  << " because no compatible configuration has been found.";
 293     *response = protocol::SessionManager::INCOMPATIBLE;
 294     return;
 295   }
 296
 297   session->set_config(config.Pass());
 298
 299   *response = protocol::SessionManager::ACCEPT;
 300
 301   HOST_LOG << "Client connected: " << session->jid();
 302
 303   // Create a client object.
 304   scoped_ptr<protocol::ConnectionToClient> connection(
 305       new protocol::ConnectionToClient(session));
 306   ClientSession* client = new ClientSession(
 307       this,
 308       audio_task_runner_,
 309       input_task_runner_,
 310       video_capture_task_runner_,
 311       video_encode_task_runner_,
 312       network_task_runner_,
 313       ui_task_runner_,
 314       connection.Pass(),
 315       desktop_environment_factory_,
 316       max_session_duration_,
 317       pairing_registry_,
 318       extensions_.get());
 319
 320   clients_.push_back(client);
 321 }
 322
 323 void ChromotingHost::set_protocol_config(
 324     scoped_ptr<protocol::CandidateSessionConfig> config) {
 325   DCHECK(CalledOnValidThread());
 326   DCHECK(config.get());
 327   DCHECK(!started_);
 328   protocol_config_ = config.Pass();
 329 }
 330
 331 void ChromotingHost::DisconnectAllClients() {
 332   DCHECK(CalledOnValidThread());
 333
 334   while (!clients_.empty()) {
 335     size_t size = clients_.size();
 336     clients_.front()->DisconnectSession();
 337     CHECK_EQ(clients_.size(), size - 1);
 338   }
 339 }
 340
 341 }  // namespace remoting