Bug 1584751 - Only open DataChannelConnections that aren't already open; r=bwc

Differential Revision: https://phabricator.services.mozilla.com/D47691

--HG--
extra : moz-landing-system : lando

netwerk/sctp/datachannel/DataChannel.cpp

@@ -645,31 +645,62 @@ uint64_t DataChannelConnection::GetMaxMessageSize() { return mMaxMessageSize; }
 #ifdef MOZ_PEERCONNECTION
 
 bool DataChannelConnection::ConnectToTransport(const std::string& aTransportId,
-                                               bool aClient, uint16_t localport,
-                                               uint16_t remoteport) {
-  {
-    MutexAutoLock lock(mLock);
+                                               const bool aClient,
+                                               const uint16_t aLocalPort,
+                                               const uint16_t aRemotePort) {
+  MutexAutoLock lock(mLock);
 
-    DC_DEBUG(("Connect DTLS local %u, remote %u", localport, remoteport));
+  MOZ_ASSERT(mMasterSocket,
+             "SCTP wasn't initialized before ConnectToTransport!");
+  static const auto paramString =
+      [](const std::string& tId, const Maybe<bool>& client,
+         const uint16_t localPort, const uint16_t remotePort) -> std::string {
+    std::ostringstream stream;
+    stream << "Transport ID: '" << tId << "', Role: '"
+           << (client ? (client.value() ? "client" : "server") : "")
+           << "', Local Port: '" << localPort << "', Remote Port: '"
+           << remotePort << "'";
+    return stream.str();
+  };
 
-    MOZ_ASSERT(mMasterSocket,
-               "SCTP wasn't initialized before ConnectToTransport!");
-    if (NS_WARN_IF(aTransportId.empty())) {
-      return false;
+  const auto params =
+      paramString(aTransportId, Some(aClient), aLocalPort, aRemotePort);
+  DC_DEBUG(("ConnectToTransport connecting DTLS transport with parameters: %s",
+            params.c_str()));
+
+  const auto currentReadyState = GetReadyState();
+  if (currentReadyState == OPEN) {
+    if (aTransportId == mTransportId && mAllocateEven.isSome() &&
+        mAllocateEven.value() == aClient && mLocalPort == aLocalPort &&
+        mRemotePort == aRemotePort) {
+      DC_WARN(
+          ("Skipping attempt to connect to an already OPEN transport with "
+           "identical parameters."));
+      return true;
     }
+    DC_WARN(
+        ("Attempting to connect to an already OPEN transport, because "
+         "different parameters were provided."));
+    DC_WARN(("Original transport parameters: %s",
+             paramString(mTransportId, mAllocateEven, mLocalPort, aRemotePort)
+                 .c_str()));
+    DC_WARN(("New transport parameters: %s", params.c_str()));
+  }
+  if (NS_WARN_IF(aTransportId.empty())) {
+    return false;
+  }
 
-    mLocalPort = localport;
-    mRemotePort = remoteport;
-    SetReadyState(CONNECTING);
-    mAllocateEven = Some(aClient);
+  mLocalPort = aLocalPort;
+  mRemotePort = aRemotePort;
+  SetReadyState(CONNECTING);
+  mAllocateEven = Some(aClient);
 
-    // Could be faster. Probably doesn't matter.
-    while (auto channel = mChannels.Get(INVALID_STREAM)) {
-      mChannels.Remove(channel);
-      channel->mStream = FindFreeStream();
-      if (channel->mStream != INVALID_STREAM) {
-        mChannels.Insert(channel);
-      }
+  // Could be faster. Probably doesn't matter.
+  while (auto channel = mChannels.Get(INVALID_STREAM)) {
+    mChannels.Remove(channel);
+    channel->mStream = FindFreeStream();
+    if (channel->mStream != INVALID_STREAM) {
+      mChannels.Insert(channel);
     }
   }
   RUN_ON_THREAD(mSTS,

netwerk/sctp/datachannel/DataChannel.h

@@ -157,8 +157,9 @@ class DataChannelConnection final : public net::NeckoTargetHolder
 #endif
 
 #ifdef SCTP_DTLS_SUPPORTED
-  bool ConnectToTransport(const std::string& aTransportId, bool aClient,
-                          uint16_t localport, uint16_t remoteport);
+  bool ConnectToTransport(const std::string& aTransportId, const bool aClient,
+                          const uint16_t aLocalPort,
+                          const uint16_t aRemotePort);
   void TransportStateChange(const std::string& aTransportId,
                             TransportLayer::State aState);
   void CompleteConnect();