src/third_party/libjingle/source/talk/p2p/base/stunport.cc

   1 /*
   2  * libjingle
   3  * Copyright 2004--2005, Google Inc.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions are met:
   7  *
   8  *  1. Redistributions of source code must retain the above copyright notice,
   9  *     this list of conditions and the following disclaimer.
  10  *  2. Redistributions in binary form must reproduce the above copyright notice,
  11  *     this list of conditions and the following disclaimer in the documentation
  12  *     and/or other materials provided with the distribution.
  13  *  3. The name of the author may not be used to endorse or promote products
  14  *     derived from this software without specific prior written permission.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
  17  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  18  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
  19  * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  20  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  21  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
  22  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
  23  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
  24  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
  25  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  26  */
  27
  28 #include "webrtc/p2p/base/stunport.h"
  29
  30 #include "webrtc/p2p/base/common.h"
  31 #include "webrtc/p2p/base/portallocator.h"
  32 #include "webrtc/p2p/base/stun.h"
  33 #include "webrtc/base/common.h"
  34 #include "webrtc/base/helpers.h"
  35 #include "webrtc/base/logging.h"
  36 #include "webrtc/base/nethelpers.h"
  37
  38 namespace cricket {
  39
  40 // TODO: Move these to a common place (used in relayport too)
  41 const int KEEPALIVE_DELAY = 10 * 1000;  // 10 seconds - sort timeouts
  42 const int RETRY_DELAY = 50;             // 50ms, from ICE spec
  43 const int RETRY_TIMEOUT = 50 * 1000;    // ICE says 50 secs
  44
  45 // Handles a binding request sent to the STUN server.
  46 class StunBindingRequest : public StunRequest {
  47  public:
  48   StunBindingRequest(UDPPort* port, bool keep_alive,
  49                      const rtc::SocketAddress& addr)
  50     : port_(port), keep_alive_(keep_alive), server_addr_(addr) {
  51     start_time_ = rtc::Time();
  52   }
  53
  54   virtual ~StunBindingRequest() {
  55   }
  56
  57   const rtc::SocketAddress& server_addr() const { return server_addr_; }
  58
  59   virtual void Prepare(StunMessage* request) {
  60     request->SetType(STUN_BINDING_REQUEST);
  61   }
  62
  63   virtual void OnResponse(StunMessage* response) {
  64     const StunAddressAttribute* addr_attr =
  65         response->GetAddress(STUN_ATTR_MAPPED_ADDRESS);
  66     if (!addr_attr) {
  67       LOG(LS_ERROR) << "Binding response missing mapped address.";
  68     } else if (addr_attr->family() != STUN_ADDRESS_IPV4 &&
  69                addr_attr->family() != STUN_ADDRESS_IPV6) {
  70       LOG(LS_ERROR) << "Binding address has bad family";
  71     } else {
  72       rtc::SocketAddress addr(addr_attr->ipaddr(), addr_attr->port());
  73       port_->OnStunBindingRequestSucceeded(server_addr_, addr);
  74     }
  75
  76     // We will do a keep-alive regardless of whether this request succeeds.
  77     // This should have almost no impact on network usage.
  78     if (keep_alive_) {
  79       port_->requests_.SendDelayed(
  80           new StunBindingRequest(port_, true, server_addr_),
  81           port_->stun_keepalive_delay());
  82     }
  83   }
  84
  85   virtual void OnErrorResponse(StunMessage* response) {
  86     const StunErrorCodeAttribute* attr = response->GetErrorCode();
  87     if (!attr) {
  88       LOG(LS_ERROR) << "Bad allocate response error code";
  89     } else {
  90       LOG(LS_ERROR) << "Binding error response:"
  91                  << " class=" << attr->eclass()
  92                  << " number=" << attr->number()
  93                  << " reason='" << attr->reason() << "'";
  94     }
  95
  96     port_->OnStunBindingOrResolveRequestFailed(server_addr_);
  97
  98     if (keep_alive_
  99         && (rtc::TimeSince(start_time_) <= RETRY_TIMEOUT)) {
 100       port_->requests_.SendDelayed(
 101           new StunBindingRequest(port_, true, server_addr_),
 102           port_->stun_keepalive_delay());
 103     }
 104   }
 105
 106   virtual void OnTimeout() {
 107     LOG(LS_ERROR) << "Binding request timed out from "
 108       << port_->GetLocalAddress().ToSensitiveString()
 109       << " (" << port_->Network()->name() << ")";
 110
 111     port_->OnStunBindingOrResolveRequestFailed(server_addr_);
 112
 113     if (keep_alive_
 114         && (rtc::TimeSince(start_time_) <= RETRY_TIMEOUT)) {
 115       port_->requests_.SendDelayed(
 116           new StunBindingRequest(port_, true, server_addr_),
 117           RETRY_DELAY);
 118     }
 119   }
 120
 121  private:
 122   UDPPort* port_;
 123   bool keep_alive_;
 124   const rtc::SocketAddress server_addr_;
 125   uint32 start_time_;
 126 };
 127
 128 UDPPort::AddressResolver::AddressResolver(
 129     rtc::PacketSocketFactory* factory)
 130     : socket_factory_(factory) {}
 131
 132 UDPPort::AddressResolver::~AddressResolver() {
 133   for (ResolverMap::iterator it = resolvers_.begin();
 134        it != resolvers_.end(); ++it) {
 135     it->second->Destroy(true);
 136   }
 137 }
 138
 139 void UDPPort::AddressResolver::Resolve(
 140     const rtc::SocketAddress& address) {
 141   if (resolvers_.find(address) != resolvers_.end())
 142     return;
 143
 144   rtc::AsyncResolverInterface* resolver =
 145       socket_factory_->CreateAsyncResolver();
 146   resolvers_.insert(
 147       std::pair<rtc::SocketAddress, rtc::AsyncResolverInterface*>(
 148           address, resolver));
 149
 150   resolver->SignalDone.connect(this,
 151                                &UDPPort::AddressResolver::OnResolveResult);
 152
 153   resolver->Start(address);
 154 }
 155
 156 bool UDPPort::AddressResolver::GetResolvedAddress(
 157     const rtc::SocketAddress& input,
 158     int family,
 159     rtc::SocketAddress* output) const {
 160   ResolverMap::const_iterator it = resolvers_.find(input);
 161   if (it == resolvers_.end())
 162     return false;
 163
 164   return it->second->GetResolvedAddress(family, output);
 165 }
 166
 167 void UDPPort::AddressResolver::OnResolveResult(
 168     rtc::AsyncResolverInterface* resolver) {
 169   for (ResolverMap::iterator it = resolvers_.begin();
 170        it != resolvers_.end(); ++it) {
 171     if (it->second == resolver) {
 172       SignalDone(it->first, resolver->GetError());
 173       return;
 174     }
 175   }
 176 }
 177
 178 UDPPort::UDPPort(rtc::Thread* thread,
 179                  rtc::PacketSocketFactory* factory,
 180                  rtc::Network* network,
 181                  rtc::AsyncPacketSocket* socket,
 182                  const std::string& username, const std::string& password)
 183     : Port(thread, factory, network, socket->GetLocalAddress().ipaddr(),
 184            username, password),
 185       requests_(thread),
 186       socket_(socket),
 187       error_(0),
 188       ready_(false),
 189       stun_keepalive_delay_(KEEPALIVE_DELAY) {
 190 }
 191
 192 UDPPort::UDPPort(rtc::Thread* thread,
 193                  rtc::PacketSocketFactory* factory,
 194                  rtc::Network* network,
 195                  const rtc::IPAddress& ip, int min_port, int max_port,
 196                  const std::string& username, const std::string& password)
 197     : Port(thread, LOCAL_PORT_TYPE, factory, network, ip, min_port, max_port,
 198            username, password),
 199       requests_(thread),
 200       socket_(NULL),
 201       error_(0),
 202       ready_(false),
 203       stun_keepalive_delay_(KEEPALIVE_DELAY) {
 204 }
 205
 206 bool UDPPort::Init() {
 207   if (!SharedSocket()) {
 208     ASSERT(socket_ == NULL);
 209     socket_ = socket_factory()->CreateUdpSocket(
 210         rtc::SocketAddress(ip(), 0), min_port(), max_port());
 211     if (!socket_) {
 212       LOG_J(LS_WARNING, this) << "UDP socket creation failed";
 213       return false;
 214     }
 215     socket_->SignalReadPacket.connect(this, &UDPPort::OnReadPacket);
 216   }
 217   socket_->SignalReadyToSend.connect(this, &UDPPort::OnReadyToSend);
 218   socket_->SignalAddressReady.connect(this, &UDPPort::OnLocalAddressReady);
 219   requests_.SignalSendPacket.connect(this, &UDPPort::OnSendPacket);
 220   return true;
 221 }
 222
 223 UDPPort::~UDPPort() {
 224   if (!SharedSocket())
 225     delete socket_;
 226 }
 227
 228 void UDPPort::PrepareAddress() {
 229   ASSERT(requests_.empty());
 230   if (socket_->GetState() == rtc::AsyncPacketSocket::STATE_BOUND) {
 231     OnLocalAddressReady(socket_, socket_->GetLocalAddress());
 232   }
 233 }
 234
 235 void UDPPort::MaybePrepareStunCandidate() {
 236   // Sending binding request to the STUN server if address is available to
 237   // prepare STUN candidate.
 238   if (!server_addresses_.empty()) {
 239     SendStunBindingRequests();
 240   } else {
 241     // Port is done allocating candidates.
 242     MaybeSetPortCompleteOrError();
 243   }
 244 }
 245
 246 Connection* UDPPort::CreateConnection(const Candidate& address,
 247                                        CandidateOrigin origin) {
 248   if (address.protocol() != "udp")
 249     return NULL;
 250
 251   if (!IsCompatibleAddress(address.address())) {
 252     return NULL;
 253   }
 254
 255   if (SharedSocket() && Candidates()[0].type() != LOCAL_PORT_TYPE) {
 256     ASSERT(false);
 257     return NULL;
 258   }
 259
 260   Connection* conn = new ProxyConnection(this, 0, address);
 261   AddConnection(conn);
 262   return conn;
 263 }
 264
 265 int UDPPort::SendTo(const void* data, size_t size,
 266                     const rtc::SocketAddress& addr,
 267                     const rtc::PacketOptions& options,
 268                     bool payload) {
 269   int sent = socket_->SendTo(data, size, addr, options);
 270   if (sent < 0) {
 271     error_ = socket_->GetError();
 272     LOG_J(LS_ERROR, this) << "UDP send of " << size
 273                           << " bytes failed with error " << error_;
 274   }
 275   return sent;
 276 }
 277
 278 int UDPPort::SetOption(rtc::Socket::Option opt, int value) {
 279   return socket_->SetOption(opt, value);
 280 }
 281
 282 int UDPPort::GetOption(rtc::Socket::Option opt, int* value) {
 283   return socket_->GetOption(opt, value);
 284 }
 285
 286 int UDPPort::GetError() {
 287   return error_;
 288 }
 289
 290 void UDPPort::OnLocalAddressReady(rtc::AsyncPacketSocket* socket,
 291                                   const rtc::SocketAddress& address) {
 292   AddAddress(address, address, rtc::SocketAddress(),
 293              UDP_PROTOCOL_NAME, "", LOCAL_PORT_TYPE,
 294              ICE_TYPE_PREFERENCE_HOST, 0, false);
 295   MaybePrepareStunCandidate();
 296 }
 297
 298 void UDPPort::OnReadPacket(
 299   rtc::AsyncPacketSocket* socket, const char* data, size_t size,
 300   const rtc::SocketAddress& remote_addr,
 301   const rtc::PacketTime& packet_time) {
 302   ASSERT(socket == socket_);
 303   ASSERT(!remote_addr.IsUnresolved());
 304
 305   // Look for a response from the STUN server.
 306   // Even if the response doesn't match one of our outstanding requests, we
 307   // will eat it because it might be a response to a retransmitted packet, and
 308   // we already cleared the request when we got the first response.
 309   if (server_addresses_.find(remote_addr) != server_addresses_.end()) {
 310     requests_.CheckResponse(data, size);
 311     return;
 312   }
 313
 314   if (Connection* conn = GetConnection(remote_addr)) {
 315     conn->OnReadPacket(data, size, packet_time);
 316   } else {
 317     Port::OnReadPacket(data, size, remote_addr, PROTO_UDP);
 318   }
 319 }
 320
 321 void UDPPort::OnReadyToSend(rtc::AsyncPacketSocket* socket) {
 322   Port::OnReadyToSend();
 323 }
 324
 325 void UDPPort::SendStunBindingRequests() {
 326   // We will keep pinging the stun server to make sure our NAT pin-hole stays
 327   // open during the call.
 328   ASSERT(requests_.empty());
 329
 330   for (ServerAddresses::const_iterator it = server_addresses_.begin();
 331        it != server_addresses_.end(); ++it) {
 332     SendStunBindingRequest(*it);
 333   }
 334 }
 335
 336 void UDPPort::ResolveStunAddress(const rtc::SocketAddress& stun_addr) {
 337   if (!resolver_) {
 338     resolver_.reset(new AddressResolver(socket_factory()));
 339     resolver_->SignalDone.connect(this, &UDPPort::OnResolveResult);
 340   }
 341
 342   resolver_->Resolve(stun_addr);
 343 }
 344
 345 void UDPPort::OnResolveResult(const rtc::SocketAddress& input,
 346                               int error) {
 347   ASSERT(resolver_.get() != NULL);
 348
 349   rtc::SocketAddress resolved;
 350   if (error != 0 ||
 351       !resolver_->GetResolvedAddress(input, ip().family(), &resolved))  {
 352     LOG_J(LS_WARNING, this) << "StunPort: stun host lookup received error "
 353                             << error;
 354     OnStunBindingOrResolveRequestFailed(input);
 355     return;
 356   }
 357
 358   server_addresses_.erase(input);
 359
 360   if (server_addresses_.find(resolved) == server_addresses_.end()) {
 361     server_addresses_.insert(resolved);
 362     SendStunBindingRequest(resolved);
 363   }
 364 }
 365
 366 void UDPPort::SendStunBindingRequest(
 367     const rtc::SocketAddress& stun_addr) {
 368   if (stun_addr.IsUnresolved()) {
 369     ResolveStunAddress(stun_addr);
 370
 371   } else if (socket_->GetState() == rtc::AsyncPacketSocket::STATE_BOUND) {
 372     // Check if |server_addr_| is compatible with the port's ip.
 373     if (IsCompatibleAddress(stun_addr)) {
 374       requests_.Send(new StunBindingRequest(this, true, stun_addr));
 375     } else {
 376       // Since we can't send stun messages to the server, we should mark this
 377       // port ready.
 378       LOG(LS_WARNING) << "STUN server address is incompatible.";
 379       OnStunBindingOrResolveRequestFailed(stun_addr);
 380     }
 381   }
 382 }
 383
 384 void UDPPort::OnStunBindingRequestSucceeded(
 385     const rtc::SocketAddress& stun_server_addr,
 386     const rtc::SocketAddress& stun_reflected_addr) {
 387   if (bind_request_succeeded_servers_.find(stun_server_addr) !=
 388           bind_request_succeeded_servers_.end()) {
 389     return;
 390   }
 391   bind_request_succeeded_servers_.insert(stun_server_addr);
 392
 393   // If socket is shared and |stun_reflected_addr| is equal to local socket
 394   // address, or if the same address has been added by another STUN server,
 395   // then discarding the stun address.
 396   // For STUN, related address is the local socket address.
 397   if ((!SharedSocket() || stun_reflected_addr != socket_->GetLocalAddress()) &&
 398       !HasCandidateWithAddress(stun_reflected_addr)) {
 399
 400     rtc::SocketAddress related_address = socket_->GetLocalAddress();
 401     if (!(candidate_filter() & CF_HOST)) {
 402       // If candidate filter doesn't have CF_HOST specified, empty raddr to
 403       // avoid local address leakage.
 404       related_address = rtc::EmptySocketAddressWithFamily(
 405           related_address.family());
 406     }
 407
 408     AddAddress(stun_reflected_addr, socket_->GetLocalAddress(),
 409                related_address, UDP_PROTOCOL_NAME, "",
 410                STUN_PORT_TYPE, ICE_TYPE_PREFERENCE_SRFLX, 0, false);
 411   }
 412   MaybeSetPortCompleteOrError();
 413 }
 414
 415 void UDPPort::OnStunBindingOrResolveRequestFailed(
 416     const rtc::SocketAddress& stun_server_addr) {
 417   if (bind_request_failed_servers_.find(stun_server_addr) !=
 418           bind_request_failed_servers_.end()) {
 419     return;
 420   }
 421   bind_request_failed_servers_.insert(stun_server_addr);
 422   MaybeSetPortCompleteOrError();
 423 }
 424
 425 void UDPPort::MaybeSetPortCompleteOrError() {
 426   if (ready_)
 427     return;
 428
 429   // Do not set port ready if we are still waiting for bind responses.
 430   const size_t servers_done_bind_request = bind_request_failed_servers_.size() +
 431       bind_request_succeeded_servers_.size();
 432   if (server_addresses_.size() != servers_done_bind_request) {
 433     return;
 434   }
 435
 436   // Setting ready status.
 437   ready_ = true;
 438
 439   // The port is "completed" if there is no stun server provided, or the bind
 440   // request succeeded for any stun server, or the socket is shared.
 441   if (server_addresses_.empty() ||
 442       bind_request_succeeded_servers_.size() > 0 ||
 443       SharedSocket()) {
 444     SignalPortComplete(this);
 445   } else {
 446     SignalPortError(this);
 447   }
 448 }
 449
 450 // TODO: merge this with SendTo above.
 451 void UDPPort::OnSendPacket(const void* data, size_t size, StunRequest* req) {
 452   StunBindingRequest* sreq = static_cast<StunBindingRequest*>(req);
 453   rtc::PacketOptions options(DefaultDscpValue());
 454   if (socket_->SendTo(data, size, sreq->server_addr(), options) < 0)
 455     PLOG(LERROR, socket_->GetError()) << "sendto";
 456 }
 457
 458 bool UDPPort::HasCandidateWithAddress(const rtc::SocketAddress& addr) const {
 459   const std::vector<Candidate>& existing_candidates = Candidates();
 460   std::vector<Candidate>::const_iterator it = existing_candidates.begin();
 461   for (; it != existing_candidates.end(); ++it) {
 462     if (it->address() == addr)
 463       return true;
 464   }
 465   return false;
 466 }
 467
 468 }  // namespace cricket