remoting/signaling/xmpp_signal_strategy.cc

   1 // Copyright 2014 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/signaling/xmpp_signal_strategy.h"
   6
   7 #include <vector>
   8
   9 #include "base/bind.h"
  10 #include "base/location.h"
  11 #include "base/logging.h"
  12 #include "base/observer_list.h"
  13 #include "base/rand_util.h"
  14 #include "base/single_thread_task_runner.h"
  15 #include "base/strings/string_number_conversions.h"
  16 #include "base/thread_task_runner_handle.h"
  17 #include "base/threading/thread_checker.h"
  18 #include "base/time/time.h"
  19 #include "base/timer/timer.h"
  20 #include "jingle/glue/proxy_resolving_client_socket.h"
  21 #include "net/cert/cert_verifier.h"
  22 #include "net/http/transport_security_state.h"
  23 #include "net/socket/client_socket_factory.h"
  24 #include "net/socket/client_socket_handle.h"
  25 #include "net/socket/ssl_client_socket.h"
  26 #include "net/url_request/url_request_context_getter.h"
  27 #include "remoting/base/buffered_socket_writer.h"
  28 #include "remoting/signaling/xmpp_login_handler.h"
  29 #include "remoting/signaling/xmpp_stream_parser.h"
  30 #include "third_party/webrtc/libjingle/xmllite/xmlelement.h"
  31
  32 // Use 50 seconds keep-alive interval, in case routers terminate
  33 // connections that are idle for more than a minute.
  34 const int kKeepAliveIntervalSeconds = 50;
  35
  36 const int kReadBufferSize = 4096;
  37
  38 const int kDefaultXmppPort = 5222;
  39 const int kDefaultHttpsPort = 443;
  40
  41 namespace remoting {
  42
  43 XmppSignalStrategy::XmppServerConfig::XmppServerConfig()
  44     : port(kDefaultXmppPort), use_tls(true) {
  45 }
  46
  47 XmppSignalStrategy::XmppServerConfig::~XmppServerConfig() {
  48 }
  49
  50 class XmppSignalStrategy::Core : public XmppLoginHandler::Delegate {
  51  public:
  52   Core(
  53       net::ClientSocketFactory* socket_factory,
  54       const scoped_refptr<net::URLRequestContextGetter>& request_context_getter,
  55       const XmppServerConfig& xmpp_server_config);
  56   ~Core() override;
  57
  58   void Connect();
  59   void Disconnect();
  60   State GetState() const;
  61   Error GetError() const;
  62   std::string GetLocalJid() const;
  63   void AddListener(Listener* listener);
  64   void RemoveListener(Listener* listener);
  65   bool SendStanza(scoped_ptr<buzz::XmlElement> stanza);
  66
  67   void SetAuthInfo(const std::string& username,
  68                    const std::string& auth_token);
  69
  70   void VerifyNoListeners();
  71
  72  private:
  73   void OnSocketConnected(int result);
  74   void OnTlsConnected(int result);
  75
  76   void ReadSocket();
  77   void OnReadResult(int result);
  78   void HandleReadResult(int result);
  79
  80   // XmppLoginHandler::Delegate interface.
  81   void SendMessage(const std::string& message) override;
  82   void StartTls() override;
  83   void OnHandshakeDone(const std::string& jid,
  84                        scoped_ptr<XmppStreamParser> parser) override;
  85   void OnLoginHandlerError(SignalStrategy::Error error) override;
  86
  87   // Event handlers for XmppStreamParser.
  88   void OnStanza(const scoped_ptr<buzz::XmlElement> stanza);
  89   void OnParserError();
  90
  91   void OnNetworkError(int error);
  92
  93   void SendKeepAlive();
  94
  95   net::ClientSocketFactory* socket_factory_;
  96   scoped_refptr<net::URLRequestContextGetter> request_context_getter_;
  97   XmppServerConfig xmpp_server_config_;
  98
  99   // Used by the |socket_|.
 100   scoped_ptr<net::CertVerifier> cert_verifier_;
 101   scoped_ptr<net::TransportSecurityState> transport_security_state_;
 102
 103   scoped_ptr<net::StreamSocket> socket_;
 104   scoped_ptr<BufferedSocketWriter> writer_;
 105   scoped_refptr<net::IOBuffer> read_buffer_;
 106   bool read_pending_;
 107   bool tls_pending_;
 108
 109   scoped_ptr<XmppLoginHandler> login_handler_;
 110   scoped_ptr<XmppStreamParser> stream_parser_;
 111   std::string jid_;
 112
 113   Error error_;
 114
 115   ObserverList<Listener, true> listeners_;
 116
 117   base::Timer keep_alive_timer_;
 118
 119   base::ThreadChecker thread_checker_;
 120
 121   DISALLOW_COPY_AND_ASSIGN(Core);
 122 };
 123
 124 XmppSignalStrategy::Core::Core(
 125     net::ClientSocketFactory* socket_factory,
 126     const scoped_refptr<net::URLRequestContextGetter>& request_context_getter,
 127     const XmppSignalStrategy::XmppServerConfig& xmpp_server_config)
 128     : socket_factory_(socket_factory),
 129       request_context_getter_(request_context_getter),
 130       xmpp_server_config_(xmpp_server_config),
 131       read_pending_(false),
 132       tls_pending_(false),
 133       error_(OK),
 134       keep_alive_timer_(
 135           FROM_HERE,
 136           base::TimeDelta::FromSeconds(kKeepAliveIntervalSeconds),
 137           base::Bind(&Core::SendKeepAlive, base::Unretained(this)),
 138           true) {
 139 #if defined(NDEBUG)
 140   // Non-secure connections are allowed only for debugging.
 141   CHECK(xmpp_server_config_.use_tls);
 142 #endif
 143 }
 144
 145 XmppSignalStrategy::Core::~Core() {
 146   Disconnect();
 147 }
 148
 149 void XmppSignalStrategy::Core::Connect() {
 150   DCHECK(thread_checker_.CalledOnValidThread());
 151
 152   // Disconnect first if we are currently connected.
 153   Disconnect();
 154
 155   error_ = OK;
 156
 157   FOR_EACH_OBSERVER(Listener, listeners_,
 158                     OnSignalStrategyStateChange(CONNECTING));
 159
 160   socket_.reset(new jingle_glue::ProxyResolvingClientSocket(
 161       socket_factory_, request_context_getter_, net::SSLConfig(),
 162       net::HostPortPair(xmpp_server_config_.host, xmpp_server_config_.port)));
 163
 164   int result = socket_->Connect(base::Bind(
 165       &Core::OnSocketConnected, base::Unretained(this)));
 166   if (result != net::ERR_IO_PENDING)
 167     OnSocketConnected(result);
 168 }
 169
 170 void XmppSignalStrategy::Core::Disconnect() {
 171   DCHECK(thread_checker_.CalledOnValidThread());
 172
 173   if (socket_) {
 174     login_handler_.reset();
 175     stream_parser_.reset();
 176     writer_.reset();
 177     socket_.reset();
 178
 179     FOR_EACH_OBSERVER(Listener, listeners_,
 180                       OnSignalStrategyStateChange(DISCONNECTED));
 181   }
 182 }
 183
 184 SignalStrategy::State XmppSignalStrategy::Core::GetState() const {
 185   DCHECK(thread_checker_.CalledOnValidThread());
 186
 187   if (stream_parser_) {
 188     DCHECK(socket_);
 189     return CONNECTED;
 190   } else if (socket_) {
 191     return CONNECTING;
 192   } else {
 193     return DISCONNECTED;
 194   }
 195 }
 196
 197 SignalStrategy::Error XmppSignalStrategy::Core::GetError() const {
 198   DCHECK(thread_checker_.CalledOnValidThread());
 199   return error_;
 200 }
 201
 202 std::string XmppSignalStrategy::Core::GetLocalJid() const {
 203   DCHECK(thread_checker_.CalledOnValidThread());
 204   return jid_;
 205 }
 206
 207 void XmppSignalStrategy::Core::AddListener(Listener* listener) {
 208   DCHECK(thread_checker_.CalledOnValidThread());
 209   listeners_.AddObserver(listener);
 210 }
 211
 212 void XmppSignalStrategy::Core::RemoveListener(Listener* listener) {
 213   DCHECK(thread_checker_.CalledOnValidThread());
 214   listeners_.RemoveObserver(listener);
 215 }
 216
 217 bool XmppSignalStrategy::Core::SendStanza(scoped_ptr<buzz::XmlElement> stanza) {
 218   DCHECK(thread_checker_.CalledOnValidThread());
 219
 220   if (!stream_parser_) {
 221     VLOG(0) << "Dropping signalling message because XMPP "
 222                "connection has been terminated.";
 223     return false;
 224   }
 225
 226   SendMessage(stanza->Str());
 227   return true;
 228 }
 229
 230 void XmppSignalStrategy::Core::SetAuthInfo(const std::string& username,
 231                                            const std::string& auth_token) {
 232   DCHECK(thread_checker_.CalledOnValidThread());
 233   xmpp_server_config_.username = username;
 234   xmpp_server_config_.auth_token = auth_token;
 235 }
 236
 237 void XmppSignalStrategy::Core::SendMessage(const std::string& message) {
 238   DCHECK(thread_checker_.CalledOnValidThread());
 239   scoped_refptr<net::IOBufferWithSize> buffer =
 240       new net::IOBufferWithSize(message.size());
 241   memcpy(buffer->data(), message.data(), message.size());
 242   writer_->Write(buffer, base::Closure());
 243 }
 244
 245 void XmppSignalStrategy::Core::StartTls() {
 246   DCHECK(thread_checker_.CalledOnValidThread());
 247   DCHECK(login_handler_);
 248
 249   // Reset the writer so we don't try to write to the raw socket anymore.
 250   DCHECK_EQ(writer_->GetBufferSize(), 0);
 251   writer_.reset();
 252
 253   DCHECK(!read_pending_);
 254
 255   scoped_ptr<net::ClientSocketHandle> socket_handle(
 256       new net::ClientSocketHandle());
 257   socket_handle->SetSocket(socket_.Pass());
 258
 259   cert_verifier_.reset(net::CertVerifier::CreateDefault());
 260   transport_security_state_.reset(new net::TransportSecurityState());
 261   net::SSLClientSocketContext context;
 262   context.cert_verifier = cert_verifier_.get();
 263   context.transport_security_state = transport_security_state_.get();
 264
 265   socket_ = socket_factory_->CreateSSLClientSocket(
 266       socket_handle.Pass(),
 267       net::HostPortPair(xmpp_server_config_.host, kDefaultHttpsPort),
 268       net::SSLConfig(), context);
 269
 270   tls_pending_ = true;
 271   int result = socket_->Connect(
 272       base::Bind(&Core::OnTlsConnected, base::Unretained(this)));
 273   if (result != net::ERR_IO_PENDING)
 274     OnTlsConnected(result);
 275 }
 276
 277 void XmppSignalStrategy::Core::OnHandshakeDone(
 278     const std::string& jid,
 279     scoped_ptr<XmppStreamParser> parser) {
 280   DCHECK(thread_checker_.CalledOnValidThread());
 281
 282   jid_ = jid;
 283   stream_parser_ = parser.Pass();
 284   stream_parser_->SetCallbacks(
 285       base::Bind(&Core::OnStanza, base::Unretained(this)),
 286       base::Bind(&Core::OnParserError, base::Unretained(this)));
 287
 288   // Don't need |login_handler_| anymore.
 289   login_handler_.reset();
 290
 291   FOR_EACH_OBSERVER(Listener, listeners_,
 292                     OnSignalStrategyStateChange(CONNECTED));
 293 }
 294
 295 void XmppSignalStrategy::Core::OnLoginHandlerError(
 296     SignalStrategy::Error error) {
 297   DCHECK(thread_checker_.CalledOnValidThread());
 298
 299   error_ = error;
 300   Disconnect();
 301 }
 302
 303 void XmppSignalStrategy::Core::OnStanza(
 304     const scoped_ptr<buzz::XmlElement> stanza) {
 305   DCHECK(thread_checker_.CalledOnValidThread());
 306
 307   ObserverListBase<Listener>::Iterator it(&listeners_);
 308   for (Listener* listener = it.GetNext(); listener; listener = it.GetNext()) {
 309     if (listener->OnSignalStrategyIncomingStanza(stanza.get()))
 310       return;
 311   }
 312 }
 313
 314 void XmppSignalStrategy::Core::OnParserError() {
 315   DCHECK(thread_checker_.CalledOnValidThread());
 316
 317   error_ = NETWORK_ERROR;
 318   Disconnect();
 319 }
 320
 321 void XmppSignalStrategy::Core::OnSocketConnected(int result) {
 322   DCHECK(thread_checker_.CalledOnValidThread());
 323
 324   if (result != net::OK) {
 325     OnNetworkError(result);
 326     return;
 327   }
 328
 329   writer_.reset(new BufferedSocketWriter());
 330   writer_->Init(socket_.get(), base::Bind(&Core::OnNetworkError,
 331                                           base::Unretained(this)));
 332
 333   XmppLoginHandler::TlsMode tls_mode;
 334   if (xmpp_server_config_.use_tls) {
 335     tls_mode = (xmpp_server_config_.port == kDefaultXmppPort)
 336                    ? XmppLoginHandler::TlsMode::WITH_HANDSHAKE
 337                    : XmppLoginHandler::TlsMode::WITHOUT_HANDSHAKE;
 338   } else {
 339     tls_mode = XmppLoginHandler::TlsMode::NO_TLS;
 340   }
 341
 342   // The server name is passed as to attribute in the <stream>. When connecting
 343   // to talk.google.com it affects the certificate the server will use for TLS:
 344   // talk.google.com uses gmail certificate when specified server is gmail.com
 345   // or googlemail.com and google.com cert otherwise. In the same time it
 346   // doesn't accept talk.google.com as target server. Here we use google.com
 347   // server name when authenticating to talk.google.com. This ensures that the
 348   // server will use google.com cert which will be accepted by the TLS
 349   // implementation in Chrome (TLS API doesn't allow specifying domain other
 350   // than the one that was passed to connect()).
 351   std::string server = xmpp_server_config_.host;
 352   if (server == "talk.google.com")
 353     server = "google.com";
 354
 355   login_handler_.reset(
 356       new XmppLoginHandler(server, xmpp_server_config_.username,
 357                            xmpp_server_config_.auth_token, tls_mode, this));
 358   login_handler_->Start();
 359
 360   ReadSocket();
 361 }
 362
 363 void XmppSignalStrategy::Core::OnTlsConnected(int result) {
 364   DCHECK(thread_checker_.CalledOnValidThread());
 365   DCHECK(tls_pending_);
 366   tls_pending_ = false;
 367
 368   if (result != net::OK) {
 369     OnNetworkError(result);
 370     return;
 371   }
 372
 373   writer_.reset(new BufferedSocketWriter());
 374   writer_->Init(socket_.get(), base::Bind(&Core::OnNetworkError,
 375                                           base::Unretained(this)));
 376
 377   login_handler_->OnTlsStarted();
 378
 379   ReadSocket();
 380 }
 381
 382 void XmppSignalStrategy::Core::ReadSocket() {
 383   DCHECK(thread_checker_.CalledOnValidThread());
 384
 385   while (socket_ && !read_pending_ && !tls_pending_) {
 386     read_buffer_ = new net::IOBuffer(kReadBufferSize);
 387     int result = socket_->Read(
 388         read_buffer_.get(), kReadBufferSize,
 389         base::Bind(&Core::OnReadResult, base::Unretained(this)));
 390     HandleReadResult(result);
 391   }
 392 }
 393
 394 void XmppSignalStrategy::Core::OnReadResult(int result) {
 395   DCHECK(thread_checker_.CalledOnValidThread());
 396   DCHECK(read_pending_);
 397   read_pending_ = false;
 398   HandleReadResult(result);
 399   ReadSocket();
 400 }
 401
 402 void XmppSignalStrategy::Core::HandleReadResult(int result) {
 403   DCHECK(thread_checker_.CalledOnValidThread());
 404
 405   if (result == net::ERR_IO_PENDING) {
 406     read_pending_ = true;
 407     return;
 408   }
 409
 410   if (result < 0) {
 411     OnNetworkError(result);
 412     return;
 413   }
 414
 415   if (result == 0) {
 416     // Connection was closed by the server.
 417     error_ = OK;
 418     Disconnect();
 419     return;
 420   }
 421
 422   if (stream_parser_) {
 423     stream_parser_->AppendData(std::string(read_buffer_->data(), result));
 424   } else {
 425     login_handler_->OnDataReceived(std::string(read_buffer_->data(), result));
 426   }
 427 }
 428
 429 void XmppSignalStrategy::Core::OnNetworkError(int error) {
 430   DCHECK(thread_checker_.CalledOnValidThread());
 431
 432   LOG(ERROR) << "XMPP socket error " << error;
 433   error_ = NETWORK_ERROR;
 434   Disconnect();
 435 }
 436
 437 void XmppSignalStrategy::Core::SendKeepAlive() {
 438   DCHECK(thread_checker_.CalledOnValidThread());
 439
 440   if (GetState() == CONNECTED)
 441     SendMessage(" ");
 442 }
 443
 444 XmppSignalStrategy::XmppSignalStrategy(
 445     net::ClientSocketFactory* socket_factory,
 446     const scoped_refptr<net::URLRequestContextGetter>& request_context_getter,
 447     const XmppServerConfig& xmpp_server_config)
 448     : core_(new Core(socket_factory,
 449                      request_context_getter,
 450                      xmpp_server_config)) {
 451 }
 452
 453 XmppSignalStrategy::~XmppSignalStrategy() {
 454   // All listeners should be removed at this point, so it's safe to detach
 455   // |core_|.
 456   base::ThreadTaskRunnerHandle::Get()->DeleteSoon(FROM_HERE, core_.release());
 457 }
 458
 459 void XmppSignalStrategy::Connect() {
 460   core_->Connect();
 461 }
 462
 463 void XmppSignalStrategy::Disconnect() {
 464   core_->Disconnect();
 465 }
 466
 467 SignalStrategy::State XmppSignalStrategy::GetState() const {
 468   return core_->GetState();
 469 }
 470
 471 SignalStrategy::Error XmppSignalStrategy::GetError() const {
 472   return core_->GetError();
 473 }
 474
 475 std::string XmppSignalStrategy::GetLocalJid() const {
 476   return core_->GetLocalJid();
 477 }
 478
 479 void XmppSignalStrategy::AddListener(Listener* listener) {
 480   core_->AddListener(listener);
 481 }
 482
 483 void XmppSignalStrategy::RemoveListener(Listener* listener) {
 484   core_->RemoveListener(listener);
 485 }
 486 bool XmppSignalStrategy::SendStanza(scoped_ptr<buzz::XmlElement> stanza) {
 487   return core_->SendStanza(stanza.Pass());
 488 }
 489
 490 std::string XmppSignalStrategy::GetNextId() {
 491   return base::Uint64ToString(base::RandUint64());
 492 }
 493
 494 void XmppSignalStrategy::SetAuthInfo(const std::string& username,
 495                                      const std::string& auth_token) {
 496   core_->SetAuthInfo(username, auth_token);
 497 }
 498
 499 }  // namespace remoting