1 files changed, 425 insertions, 0 deletions
diff --git a/third_party/libwebrtc/pc/data_channel_controller.cc b/third_party/libwebrtc/pc/data_channel_controller.cc
new file mode 100644
index 0000000000..36f11fe12e
--- /dev/null
+++ b/third_party/libwebrtc/pc/data_channel_controller.cc
@@ -0,0 +1,425 @@
+/*
+ *  Copyright 2019 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.
+ */
+
+#include "pc/data_channel_controller.h"
+
+#include <utility>
+
+#include "api/peer_connection_interface.h"
+#include "api/rtc_error.h"
+#include "pc/peer_connection_internal.h"
+#include "pc/sctp_utils.h"
+#include "rtc_base/logging.h"
+
+namespace webrtc {
+
+DataChannelController::~DataChannelController() {
+  // Since channels may have multiple owners, we cannot guarantee that
+  // they will be deallocated before destroying the controller.
+  // Therefore, detach them from the controller.
+  for (auto channel : sctp_data_channels_) {
+    channel->DetachFromController();
+  }
+}
+
+bool DataChannelController::HasDataChannels() const {
+  RTC_DCHECK_RUN_ON(signaling_thread());
+  return !sctp_data_channels_.empty();
+}
+
+bool DataChannelController::SendData(int sid,
+                                     const SendDataParams& params,
+                                     const rtc::CopyOnWriteBuffer& payload,
+                                     cricket::SendDataResult* result) {
+  if (data_channel_transport())
+    return DataChannelSendData(sid, params, payload, result);
+  RTC_LOG(LS_ERROR) << "SendData called before transport is ready";
+  return false;
+}
+
+bool DataChannelController::ConnectDataChannel(
+    SctpDataChannel* webrtc_data_channel) {
+  RTC_DCHECK_RUN_ON(signaling_thread());
+  if (!data_channel_transport()) {
+    // Don't log an error here, because DataChannels are expected to call
+    // ConnectDataChannel in this state. It's the only way to initially tell
+    // whether or not the underlying transport is ready.
+    return false;
+  }
+  SignalDataChannelTransportWritable_s.connect(
+      webrtc_data_channel, &SctpDataChannel::OnTransportReady);
+  SignalDataChannelTransportReceivedData_s.connect(
+      webrtc_data_channel, &SctpDataChannel::OnDataReceived);
+  SignalDataChannelTransportChannelClosing_s.connect(
+      webrtc_data_channel, &SctpDataChannel::OnClosingProcedureStartedRemotely);
+  SignalDataChannelTransportChannelClosed_s.connect(
+      webrtc_data_channel, &SctpDataChannel::OnClosingProcedureComplete);
+  return true;
+}
+
+void DataChannelController::DisconnectDataChannel(
+    SctpDataChannel* webrtc_data_channel) {
+  RTC_DCHECK_RUN_ON(signaling_thread());
+  if (!data_channel_transport()) {
+    RTC_LOG(LS_ERROR)
+        << "DisconnectDataChannel called when sctp_transport_ is NULL.";
+    return;
+  }
+  SignalDataChannelTransportWritable_s.disconnect(webrtc_data_channel);
+  SignalDataChannelTransportReceivedData_s.disconnect(webrtc_data_channel);
+  SignalDataChannelTransportChannelClosing_s.disconnect(webrtc_data_channel);
+  SignalDataChannelTransportChannelClosed_s.disconnect(webrtc_data_channel);
+}
+
+void DataChannelController::AddSctpDataStream(int sid) {
+  if (data_channel_transport()) {
+    network_thread()->BlockingCall([this, sid] {
+      if (data_channel_transport()) {
+        data_channel_transport()->OpenChannel(sid);
+      }
+    });
+  }
+}
+
+void DataChannelController::RemoveSctpDataStream(int sid) {
+  if (data_channel_transport()) {
+    network_thread()->BlockingCall([this, sid] {
+      if (data_channel_transport()) {
+        data_channel_transport()->CloseChannel(sid);
+      }
+    });
+  }
+}
+
+bool DataChannelController::ReadyToSendData() const {
+  RTC_DCHECK_RUN_ON(signaling_thread());
+  return (data_channel_transport() && data_channel_transport_ready_to_send_);
+}
+
+void DataChannelController::OnDataReceived(
+    int channel_id,
+    DataMessageType type,
+    const rtc::CopyOnWriteBuffer& buffer) {
+  RTC_DCHECK_RUN_ON(network_thread());
+  cricket::ReceiveDataParams params;
+  params.sid = channel_id;
+  params.type = type;
+  signaling_thread()->PostTask(
+      [self = weak_factory_.GetWeakPtr(), params, buffer] {
+        if (self) {
+          RTC_DCHECK_RUN_ON(self->signaling_thread());
+          // TODO(bugs.webrtc.org/11547): The data being received should be
+          // delivered on the network thread. The way HandleOpenMessage_s works
+          // right now is that it's called for all types of buffers and operates
+          // as a selector function. Change this so that it's only called for
+          // buffers that it should be able to handle. Once we do that, we can
+          // deliver all other buffers on the network thread (change
+          // SignalDataChannelTransportReceivedData_s to
+          // SignalDataChannelTransportReceivedData_n).
+          if (!self->HandleOpenMessage_s(params, buffer)) {
+            self->SignalDataChannelTransportReceivedData_s(params, buffer);
+          }
+        }
+      });
+}
+
+void DataChannelController::OnChannelClosing(int channel_id) {
+  RTC_DCHECK_RUN_ON(network_thread());
+  signaling_thread()->PostTask([self = weak_factory_.GetWeakPtr(), channel_id] {
+    if (self) {
+      RTC_DCHECK_RUN_ON(self->signaling_thread());
+      self->SignalDataChannelTransportChannelClosing_s(channel_id);
+    }
+  });
+}
+
+void DataChannelController::OnChannelClosed(int channel_id) {
+  RTC_DCHECK_RUN_ON(network_thread());
+  signaling_thread()->PostTask([self = weak_factory_.GetWeakPtr(), channel_id] {
+    if (self) {
+      RTC_DCHECK_RUN_ON(self->signaling_thread());
+      self->SignalDataChannelTransportChannelClosed_s(channel_id);
+    }
+  });
+}
+
+void DataChannelController::OnReadyToSend() {
+  RTC_DCHECK_RUN_ON(network_thread());
+  signaling_thread()->PostTask([self = weak_factory_.GetWeakPtr()] {
+    if (self) {
+      RTC_DCHECK_RUN_ON(self->signaling_thread());
+      self->data_channel_transport_ready_to_send_ = true;
+      self->SignalDataChannelTransportWritable_s(
+          self->data_channel_transport_ready_to_send_);
+    }
+  });
+}
+
+void DataChannelController::OnTransportClosed(RTCError error) {
+  RTC_DCHECK_RUN_ON(network_thread());
+  signaling_thread()->PostTask([self = weak_factory_.GetWeakPtr(), error] {
+    if (self) {
+      RTC_DCHECK_RUN_ON(self->signaling_thread());
+      self->OnTransportChannelClosed(error);
+    }
+  });
+}
+
+void DataChannelController::SetupDataChannelTransport_n() {
+  RTC_DCHECK_RUN_ON(network_thread());
+
+  // There's a new data channel transport.  This needs to be signaled to the
+  // `sctp_data_channels_` so that they can reopen and reconnect.  This is
+  // necessary when bundling is applied.
+  NotifyDataChannelsOfTransportCreated();
+}
+
+void DataChannelController::TeardownDataChannelTransport_n() {
+  RTC_DCHECK_RUN_ON(network_thread());
+  if (data_channel_transport()) {
+    data_channel_transport()->SetDataSink(nullptr);
+  }
+  set_data_channel_transport(nullptr);
+}
+
+void DataChannelController::OnTransportChanged(
+    DataChannelTransportInterface* new_data_channel_transport) {
+  RTC_DCHECK_RUN_ON(network_thread());
+  if (data_channel_transport() &&
+      data_channel_transport() != new_data_channel_transport) {
+    // Changed which data channel transport is used for `sctp_mid_` (eg. now
+    // it's bundled).
+    data_channel_transport()->SetDataSink(nullptr);
+    set_data_channel_transport(new_data_channel_transport);
+    if (new_data_channel_transport) {
+      new_data_channel_transport->SetDataSink(this);
+
+      // There's a new data channel transport.  This needs to be signaled to the
+      // `sctp_data_channels_` so that they can reopen and reconnect.  This is
+      // necessary when bundling is applied.
+      NotifyDataChannelsOfTransportCreated();
+    }
+  }
+}
+
+std::vector<DataChannelStats> DataChannelController::GetDataChannelStats()
+    const {
+  RTC_DCHECK_RUN_ON(signaling_thread());
+  std::vector<DataChannelStats> stats;
+  stats.reserve(sctp_data_channels_.size());
+  for (const auto& channel : sctp_data_channels_)
+    stats.push_back(channel->GetStats());
+  return stats;
+}
+
+bool DataChannelController::HandleOpenMessage_s(
+    const cricket::ReceiveDataParams& params,
+    const rtc::CopyOnWriteBuffer& buffer) {
+  if (params.type == DataMessageType::kControl && IsOpenMessage(buffer)) {
+    // Received OPEN message; parse and signal that a new data channel should
+    // be created.
+    std::string label;
+    InternalDataChannelInit config;
+    config.id = params.sid;
+    if (!ParseDataChannelOpenMessage(buffer, &label, &config)) {
+      RTC_LOG(LS_WARNING) << "Failed to parse the OPEN message for sid "
+                          << params.sid;
+      return true;
+    }
+    config.open_handshake_role = InternalDataChannelInit::kAcker;
+    OnDataChannelOpenMessage(label, config);
+    return true;
+  }
+  return false;
+}
+
+void DataChannelController::OnDataChannelOpenMessage(
+    const std::string& label,
+    const InternalDataChannelInit& config) {
+  rtc::scoped_refptr<DataChannelInterface> channel(
+      InternalCreateDataChannelWithProxy(label, &config));
+  if (!channel.get()) {
+    RTC_LOG(LS_ERROR) << "Failed to create DataChannel from the OPEN message.";
+    return;
+  }
+
+  pc_->Observer()->OnDataChannel(std::move(channel));
+  pc_->NoteDataAddedEvent();
+}
+
+rtc::scoped_refptr<DataChannelInterface>
+DataChannelController::InternalCreateDataChannelWithProxy(
+    const std::string& label,
+    const InternalDataChannelInit* config) {
+  RTC_DCHECK_RUN_ON(signaling_thread());
+  if (pc_->IsClosed()) {
+    return nullptr;
+  }
+
+  rtc::scoped_refptr<SctpDataChannel> channel =
+      InternalCreateSctpDataChannel(label, config);
+  if (channel) {
+    return SctpDataChannel::CreateProxy(channel);
+  }
+
+  return nullptr;
+}
+
+rtc::scoped_refptr<SctpDataChannel>
+DataChannelController::InternalCreateSctpDataChannel(
+    const std::string& label,
+    const InternalDataChannelInit* config) {
+  RTC_DCHECK_RUN_ON(signaling_thread());
+  InternalDataChannelInit new_config =
+      config ? (*config) : InternalDataChannelInit();
+  if (new_config.id < 0) {
+    rtc::SSLRole role;
+    if ((pc_->GetSctpSslRole(&role)) &&
+        !sid_allocator_.AllocateSid(role, &new_config.id)) {
+      RTC_LOG(LS_ERROR) << "No id can be allocated for the SCTP data channel.";
+      return nullptr;
+    }
+  } else if (!sid_allocator_.ReserveSid(new_config.id)) {
+    RTC_LOG(LS_ERROR) << "Failed to create a SCTP data channel "
+                         "because the id is already in use or out of range.";
+    return nullptr;
+  }
+  rtc::scoped_refptr<SctpDataChannel> channel(SctpDataChannel::Create(
+      this, label, new_config, signaling_thread(), network_thread()));
+  if (!channel) {
+    sid_allocator_.ReleaseSid(new_config.id);
+    return nullptr;
+  }
+  sctp_data_channels_.push_back(channel);
+  channel->SignalClosed.connect(
+      pc_, &PeerConnectionInternal::OnSctpDataChannelClosed);
+  SignalSctpDataChannelCreated_(channel.get());
+  return channel;
+}
+
+void DataChannelController::AllocateSctpSids(rtc::SSLRole role) {
+  RTC_DCHECK_RUN_ON(signaling_thread());
+  std::vector<rtc::scoped_refptr<SctpDataChannel>> channels_to_close;
+  for (const auto& channel : sctp_data_channels_) {
+    if (channel->id() < 0) {
+      int sid;
+      if (!sid_allocator_.AllocateSid(role, &sid)) {
+        RTC_LOG(LS_ERROR) << "Failed to allocate SCTP sid, closing channel.";
+        channels_to_close.push_back(channel);
+        continue;
+      }
+      channel->SetSctpSid(sid);
+    }
+  }
+  // Since closing modifies the list of channels, we have to do the actual
+  // closing outside the loop.
+  for (const auto& channel : channels_to_close) {
+    channel->CloseAbruptlyWithDataChannelFailure("Failed to allocate SCTP SID");
+  }
+}
+
+void DataChannelController::OnSctpDataChannelClosed(SctpDataChannel* channel) {
+  RTC_DCHECK_RUN_ON(signaling_thread());
+  for (auto it = sctp_data_channels_.begin(); it != sctp_data_channels_.end();
+       ++it) {
+    if (it->get() == channel) {
+      if (channel->id() >= 0) {
+        // After the closing procedure is done, it's safe to use this ID for
+        // another data channel.
+        sid_allocator_.ReleaseSid(channel->id());
+      }
+      // Since this method is triggered by a signal from the DataChannel,
+      // we can't free it directly here; we need to free it asynchronously.
+      sctp_data_channels_to_free_.push_back(*it);
+      sctp_data_channels_.erase(it);
+      signaling_thread()->PostTask([self = weak_factory_.GetWeakPtr()] {
+        if (self) {
+          RTC_DCHECK_RUN_ON(self->signaling_thread());
+          self->sctp_data_channels_to_free_.clear();
+        }
+      });
+      return;
+    }
+  }
+}
+
+void DataChannelController::OnTransportChannelClosed(RTCError error) {
+  RTC_DCHECK_RUN_ON(signaling_thread());
+  // Use a temporary copy of the SCTP DataChannel list because the
+  // DataChannel may callback to us and try to modify the list.
+  std::vector<rtc::scoped_refptr<SctpDataChannel>> temp_sctp_dcs;
+  temp_sctp_dcs.swap(sctp_data_channels_);
+  for (const auto& channel : temp_sctp_dcs) {
+    channel->OnTransportChannelClosed(error);
+  }
+}
+
+DataChannelTransportInterface* DataChannelController::data_channel_transport()
+    const {
+  // TODO(bugs.webrtc.org/11547): Only allow this accessor to be called on the
+  // network thread.
+  // RTC_DCHECK_RUN_ON(network_thread());
+  return data_channel_transport_;
+}
+
+void DataChannelController::set_data_channel_transport(
+    DataChannelTransportInterface* transport) {
+  RTC_DCHECK_RUN_ON(network_thread());
+  data_channel_transport_ = transport;
+}
+
+bool DataChannelController::DataChannelSendData(
+    int sid,
+    const SendDataParams& params,
+    const rtc::CopyOnWriteBuffer& payload,
+    cricket::SendDataResult* result) {
+  // TODO(bugs.webrtc.org/11547): Expect method to be called on the network
+  // thread instead. Remove the BlockingCall() below and move assocated state to
+  // the network thread.
+  RTC_DCHECK_RUN_ON(signaling_thread());
+  RTC_DCHECK(data_channel_transport());
+
+  RTCError error = network_thread()->BlockingCall([this, sid, params, payload] {
+    return data_channel_transport()->SendData(sid, params, payload);
+  });
+
+  if (error.ok()) {
+    *result = cricket::SendDataResult::SDR_SUCCESS;
+    return true;
+  } else if (error.type() == RTCErrorType::RESOURCE_EXHAUSTED) {
+    // SCTP transport uses RESOURCE_EXHAUSTED when it's blocked.
+    // TODO(mellem):  Stop using RTCError here and get rid of the mapping.
+    *result = cricket::SendDataResult::SDR_BLOCK;
+    return false;
+  }
+  *result = cricket::SendDataResult::SDR_ERROR;
+  return false;
+}
+
+void DataChannelController::NotifyDataChannelsOfTransportCreated() {
+  RTC_DCHECK_RUN_ON(network_thread());
+  signaling_thread()->PostTask([self = weak_factory_.GetWeakPtr()] {
+    if (self) {
+      RTC_DCHECK_RUN_ON(self->signaling_thread());
+      for (const auto& channel : self->sctp_data_channels_) {
+        channel->OnTransportChannelCreated();
+      }
+    }
+  });
+}
+
+rtc::Thread* DataChannelController::network_thread() const {
+  return pc_->network_thread();
+}
+rtc::Thread* DataChannelController::signaling_thread() const {
+  return pc_->signaling_thread();
+}
+
+}  // namespace webrtc