Add signaling to support ICE renomination.

webrtc/p2p/base/p2ptransportchannel.cc

 /*
  *  Copyright 2004 The WebRTC Project Authors. All rights reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 277 matching lines @@
       LOG_J(LS_VERBOSE, this) << "Ice not completed yet for this channel as "
                               << network->ToString()
                               << " has more than 1 connection.";
       return TransportChannelState::STATE_CONNECTING;
     }
   }
 
   return TransportChannelState::STATE_COMPLETED;
 }
 
-void P2PTransportChannel::SetIceCredentials(const std::string& ice_ufrag,
-                                            const std::string& ice_pwd) {
+void P2PTransportChannel::SetIceParameters(const IceParameters& ice_params) {
   ASSERT(worker_thread_ == rtc::Thread::Current());
-  ice_ufrag_ = ice_ufrag;
-  ice_pwd_ = ice_pwd;
+  ice_parameters_ = ice_params;
   // Note: Candidate gathering will restart when MaybeStartGathering is next
   // called.
 }
 
-void P2PTransportChannel::SetRemoteIceCredentials(const std::string& ice_ufrag,
-                                                  const std::string& ice_pwd) {
+void P2PTransportChannel::SetRemoteIceParameters(
+    const IceParameters& ice_params) {
   ASSERT(worker_thread_ == rtc::Thread::Current());
+  LOG(LS_INFO) << "Remote supports ICE renomination ? "
+               << ice_params.renomination;
   IceParameters* current_ice = remote_ice();
-  IceParameters new_ice(ice_ufrag, ice_pwd);
-  if (!current_ice || *current_ice != new_ice) {
+  if (!current_ice || *current_ice != ice_params) {

[Taylor Brandstetter, 2016/08/08 22:28:15]

Should we support renomination going from true to false (or the reverse)? I
don't see a test for that.

[honghaiz3, 2016/08/11 04:57:57]

Implementation-wide, I think it allows renomination to change. It will take what
ever is set last. 
But standard/protocol-wise, officially supporting it would require extra
engineering work (at least for the tests you mentioned). 
In practice, there is little reason to change renomination in a session. So I'd
prefer not spending time on that test. 

     // Keep the ICE credentials so that newer connections
     // are prioritized over the older ones.
-    remote_ice_parameters_.push_back(new_ice);
+    remote_ice_parameters_.push_back(ice_params);
   }
 
   // Update the pwd of remote candidate if needed.
   for (RemoteCandidate& candidate : remote_candidates_) {
-    if (candidate.username() == ice_ufrag && candidate.password().empty()) {
-      candidate.set_password(ice_pwd);
+    if (candidate.username() == ice_params.ufrag &&
+        candidate.password().empty()) {
+      candidate.set_password(ice_params.pwd);
     }
   }
   // We need to update the credentials and generation for any peer reflexive
   // candidates.
   for (Connection* conn : connections_) {
-    conn->MaybeSetRemoteIceCredentialsAndGeneration(
-        ice_ufrag, ice_pwd,
-        static_cast<int>(remote_ice_parameters_.size() - 1));
+    conn->MaybeSetRemoteIceParametersAndGeneration(
+        ice_params, static_cast<int>(remote_ice_parameters_.size() - 1));
   }
   // Updating the remote ICE candidate generation could change the sort order.
   RequestSortAndStateUpdate();
 }
 
 void P2PTransportChannel::SetRemoteIceMode(IceMode mode) {
   remote_ice_mode_ = mode;
 }
 
 void P2PTransportChannel::SetIceConfig(const IceConfig& config) {
@@ skipping 62 matching lines @@
     config_.receiving_switching_delay = config.receiving_switching_delay;
     LOG(LS_INFO) << "Set receiving_switching_delay to"
                  << *config_.receiving_switching_delay;
   }
 
   if (config_.default_nomination_mode != config.default_nomination_mode) {
     config_.default_nomination_mode = config.default_nomination_mode;
     LOG(LS_INFO) << "Set default nomination mode to "
                  << static_cast<int>(config_.default_nomination_mode);
   }
+  config_.use_renomination_if_remote_supports =
+      config.use_renomination_if_remote_supports;
+  LOG(LS_INFO) << "Set use_renomination_if_remote_supports to "
+               << config_.use_renomination_if_remote_supports;
 }
 
 const IceConfig& P2PTransportChannel::config() const {
   return config_;
 }
 
 void P2PTransportChannel::MaybeStartGathering() {
-  if (ice_ufrag_.empty() || ice_pwd_.empty()) {
+  if (ice_parameters_.ufrag.empty() || ice_parameters_.pwd.empty()) {
     return;
   }
   // Start gathering if we never started before, or if an ICE restart occurred.
   if (allocator_sessions_.empty() ||
       IceCredentialsChanged(allocator_sessions_.back()->ice_ufrag(),
-                            allocator_sessions_.back()->ice_pwd(), ice_ufrag_,
-                            ice_pwd_)) {
+                            allocator_sessions_.back()->ice_pwd(),
+                            ice_parameters_.ufrag, ice_parameters_.pwd)) {
     if (gathering_state_ != kIceGatheringGathering) {
       gathering_state_ = kIceGatheringGathering;
       SignalGatheringState(this);
     }
     // Time for a new allocator.
     std::unique_ptr<PortAllocatorSession> pooled_session =
-        allocator_->TakePooledSession(transport_name(), component(), ice_ufrag_,
-                                      ice_pwd_);
+        allocator_->TakePooledSession(transport_name(), component(),
+                                      ice_parameters_.ufrag,
+                                      ice_parameters_.pwd);
     if (pooled_session) {
       AddAllocatorSession(std::move(pooled_session));
       PortAllocatorSession* raw_pooled_session =
           allocator_sessions_.back().get();
       // Process the pooled session's existing candidates/ports, if they exist.
       OnCandidatesReady(raw_pooled_session,
                         raw_pooled_session->ReadyCandidates());
       for (PortInterface* port : allocator_sessions_.back()->ReadyPorts()) {
         OnPortReady(raw_pooled_session, port);
       }
       if (allocator_sessions_.back()->CandidatesAllocationDone()) {
         OnCandidatesAllocationDone(raw_pooled_session);
       }
     } else {
       AddAllocatorSession(allocator_->CreateSession(
-          SessionId(), transport_name(), component(), ice_ufrag_, ice_pwd_));
+          SessionId(), transport_name(), component(), ice_parameters_.ufrag,
+          ice_parameters_.pwd));
       allocator_sessions_.back()->StartGettingPorts();
     }
   }
 }
 
 // A new port is available, attempt to make connections for it
 void P2PTransportChannel::OnPortReady(PortAllocatorSession *session,
                                       PortInterface* port) {
   ASSERT(worker_thread_ == rtc::Thread::Current());
 
@@ skipping 1130 matching lines @@
   }
 }
 
 // Apart from sending ping from |conn| this method also updates
 // |use_candidate_attr| and |nomination| flags. One of the flags is set to
 // nominate |conn| if this channel is in CONTROLLING.
 void P2PTransportChannel::PingConnection(Connection* conn) {
   bool use_candidate_attr = false;
   uint32_t nomination = 0;
   if (ice_role_ == ICEROLE_CONTROLLING) {
-    if (remote_supports_renomination_) {
+    bool remote_supports_renomination =
+        !remote_ice_parameters_.empty() &&
+        remote_ice_parameters_.back().renomination;
+    if (remote_supports_renomination &&
+        config_.use_renomination_if_remote_supports) {
       nomination = GetNominationAttr(conn);
     } else {
       use_candidate_attr =
           GetUseCandidateAttr(conn, config_.default_nomination_mode);
     }
   }
   conn->set_nomination(nomination);
   conn->set_use_candidate_attr(use_candidate_attr);
   last_ping_sent_ms_ = rtc::TimeMillis();
   conn->Ping(last_ping_sent_ms_);
@@ skipping 317 matching lines @@
 
   // During the initial state when nothing has been pinged yet, return the first
   // one in the ordered |connections_|.
   return *(std::find_if(connections_.begin(), connections_.end(),
                         [conn1, conn2](Connection* conn) {
                           return conn == conn1 || conn == conn2;
                         }));
 }
 
 }  // namespace cricket