|  | /* | 
|  | *  Copyright 2016 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 "webrtc/pc/quicdatachannel.h" | 
|  |  | 
|  | #include "webrtc/base/bind.h" | 
|  | #include "webrtc/base/bytebuffer.h" | 
|  | #include "webrtc/base/copyonwritebuffer.h" | 
|  | #include "webrtc/base/logging.h" | 
|  | #include "webrtc/p2p/quic/quictransportchannel.h" | 
|  | #include "webrtc/p2p/quic/reliablequicstream.h" | 
|  |  | 
|  | namespace webrtc { | 
|  |  | 
|  | void WriteQuicDataChannelMessageHeader(int data_channel_id, | 
|  | uint64_t message_id, | 
|  | rtc::CopyOnWriteBuffer* header) { | 
|  | RTC_DCHECK(header); | 
|  | // 64-bit varints require at most 10 bytes (7*10 == 70), and 32-bit varints | 
|  | // require at most 5 bytes (7*5 == 35). | 
|  | size_t max_length = 15; | 
|  | rtc::ByteBufferWriter byte_buffer(nullptr, max_length, | 
|  | rtc::ByteBuffer::ByteOrder::ORDER_HOST); | 
|  | byte_buffer.WriteUVarint(data_channel_id); | 
|  | byte_buffer.WriteUVarint(message_id); | 
|  | header->SetData(byte_buffer.Data(), byte_buffer.Length()); | 
|  | } | 
|  |  | 
|  | bool ParseQuicDataMessageHeader(const char* data, | 
|  | size_t len, | 
|  | int* data_channel_id, | 
|  | uint64_t* message_id, | 
|  | size_t* bytes_read) { | 
|  | RTC_DCHECK(data_channel_id); | 
|  | RTC_DCHECK(message_id); | 
|  | RTC_DCHECK(bytes_read); | 
|  |  | 
|  | rtc::ByteBufferReader byte_buffer(data, len, rtc::ByteBuffer::ORDER_HOST); | 
|  | uint64_t dcid; | 
|  | if (!byte_buffer.ReadUVarint(&dcid)) { | 
|  | LOG(LS_ERROR) << "Could not read the data channel ID"; | 
|  | return false; | 
|  | } | 
|  | *data_channel_id = dcid; | 
|  | if (!byte_buffer.ReadUVarint(message_id)) { | 
|  | LOG(LS_ERROR) << "Could not read message ID for data channel " | 
|  | << *data_channel_id; | 
|  | return false; | 
|  | } | 
|  | size_t remaining_bytes = byte_buffer.Length(); | 
|  | *bytes_read = len - remaining_bytes; | 
|  | return true; | 
|  | } | 
|  |  | 
|  | QuicDataChannel::QuicDataChannel(rtc::Thread* signaling_thread, | 
|  | rtc::Thread* worker_thread, | 
|  | rtc::Thread* network_thread, | 
|  | const std::string& label, | 
|  | const DataChannelInit& config) | 
|  | : signaling_thread_(signaling_thread), | 
|  | worker_thread_(worker_thread), | 
|  | network_thread_(network_thread), | 
|  | id_(config.id), | 
|  | state_(kConnecting), | 
|  | buffered_amount_(0), | 
|  | next_message_id_(0), | 
|  | label_(label), | 
|  | protocol_(config.protocol) {} | 
|  |  | 
|  | QuicDataChannel::~QuicDataChannel() {} | 
|  |  | 
|  | void QuicDataChannel::RegisterObserver(DataChannelObserver* observer) { | 
|  | RTC_DCHECK(signaling_thread_->IsCurrent()); | 
|  | observer_ = observer; | 
|  | } | 
|  |  | 
|  | void QuicDataChannel::UnregisterObserver() { | 
|  | RTC_DCHECK(signaling_thread_->IsCurrent()); | 
|  | observer_ = nullptr; | 
|  | } | 
|  |  | 
|  | bool QuicDataChannel::Send(const DataBuffer& buffer) { | 
|  | RTC_DCHECK(signaling_thread_->IsCurrent()); | 
|  | if (state_ != kOpen) { | 
|  | LOG(LS_ERROR) << "QUIC data channel " << id_ | 
|  | << " is not open so cannot send."; | 
|  | return false; | 
|  | } | 
|  | return network_thread_->Invoke<bool>( | 
|  | RTC_FROM_HERE, rtc::Bind(&QuicDataChannel::Send_n, this, buffer)); | 
|  | } | 
|  |  | 
|  | bool QuicDataChannel::Send_n(const DataBuffer& buffer) { | 
|  | RTC_DCHECK(network_thread_->IsCurrent()); | 
|  |  | 
|  | // Encode and send the header containing the data channel ID and message ID. | 
|  | rtc::CopyOnWriteBuffer header; | 
|  | WriteQuicDataChannelMessageHeader(id_, ++next_message_id_, &header); | 
|  | RTC_DCHECK(quic_transport_channel_); | 
|  | cricket::ReliableQuicStream* stream = | 
|  | quic_transport_channel_->CreateQuicStream(); | 
|  | RTC_DCHECK(stream); | 
|  |  | 
|  | // Send the header with a FIN if the message is empty. | 
|  | bool header_fin = (buffer.size() == 0); | 
|  | rtc::StreamResult header_result = | 
|  | stream->Write(header.data<char>(), header.size(), header_fin); | 
|  |  | 
|  | if (header_result == rtc::SR_BLOCK) { | 
|  | // The header is write blocked but we should try sending the message. Since | 
|  | // the ReliableQuicStream queues data in order, if the header is write | 
|  | // blocked then the message will be write blocked. Otherwise if the message | 
|  | // is sent then the header is sent. | 
|  | LOG(LS_INFO) << "Stream " << stream->id() | 
|  | << " header is write blocked for QUIC data channel " << id_; | 
|  | } else if (header_result != rtc::SR_SUCCESS) { | 
|  | LOG(LS_ERROR) << "Stream " << stream->id() | 
|  | << " failed to write header for QUIC data channel " << id_ | 
|  | << ". Unexpected error " << header_result; | 
|  | return false; | 
|  | } | 
|  |  | 
|  | // If the message is not empty, then send the message with a FIN. | 
|  | bool message_fin = true; | 
|  | rtc::StreamResult message_result = | 
|  | header_fin ? header_result : stream->Write(buffer.data.data<char>(), | 
|  | buffer.size(), message_fin); | 
|  |  | 
|  | if (message_result == rtc::SR_SUCCESS) { | 
|  | // The message is sent and we don't need this QUIC stream. | 
|  | LOG(LS_INFO) << "Stream " << stream->id() | 
|  | << " successfully wrote message for QUIC data channel " << id_; | 
|  | stream->Close(); | 
|  | return true; | 
|  | } | 
|  | // TODO(mikescarlett): Register the ReliableQuicStream's priority to the | 
|  | // QuicWriteBlockedList so that the QUIC session doesn't drop messages when | 
|  | // the QUIC transport channel becomes unwritable. | 
|  | if (message_result == rtc::SR_BLOCK) { | 
|  | // The QUIC stream is write blocked, so the message is queued by the QUIC | 
|  | // session. If this is due to the QUIC not being writable, it will be sent | 
|  | // once QUIC becomes writable again. Otherwise it may be due to exceeding | 
|  | // the QUIC flow control limit, in which case the remote peer's QUIC session | 
|  | // will tell the QUIC stream to send more data. | 
|  | LOG(LS_INFO) << "Stream " << stream->id() | 
|  | << " message is write blocked for QUIC data channel " << id_; | 
|  | SetBufferedAmount_w(buffered_amount_ + stream->queued_data_bytes()); | 
|  | stream->SignalQueuedBytesWritten.connect( | 
|  | this, &QuicDataChannel::OnQueuedBytesWritten); | 
|  | write_blocked_quic_streams_[stream->id()] = stream; | 
|  | // The QUIC stream will be removed from |write_blocked_quic_streams_| once | 
|  | // it closes. | 
|  | stream->SignalClosed.connect(this, | 
|  | &QuicDataChannel::OnWriteBlockedStreamClosed); | 
|  | return true; | 
|  | } | 
|  | LOG(LS_ERROR) << "Stream " << stream->id() | 
|  | << " failed to write message for QUIC data channel " << id_ | 
|  | << ". Unexpected error: " << message_result; | 
|  | return false; | 
|  | } | 
|  |  | 
|  | void QuicDataChannel::OnQueuedBytesWritten(net::QuicStreamId stream_id, | 
|  | uint64_t queued_bytes_written) { | 
|  | RTC_DCHECK(worker_thread_->IsCurrent()); | 
|  | SetBufferedAmount_w(buffered_amount_ - queued_bytes_written); | 
|  | const auto& kv = write_blocked_quic_streams_.find(stream_id); | 
|  | if (kv == write_blocked_quic_streams_.end()) { | 
|  | RTC_NOTREACHED(); | 
|  | return; | 
|  | } | 
|  | cricket::ReliableQuicStream* stream = kv->second; | 
|  | // True if the QUIC stream is done sending data. | 
|  | if (stream->fin_sent()) { | 
|  | LOG(LS_INFO) << "Stream " << stream->id() | 
|  | << " successfully wrote data for QUIC data channel " << id_; | 
|  | stream->Close(); | 
|  | } | 
|  | } | 
|  |  | 
|  | void QuicDataChannel::SetBufferedAmount_w(uint64_t buffered_amount) { | 
|  | RTC_DCHECK(worker_thread_->IsCurrent()); | 
|  | buffered_amount_ = buffered_amount; | 
|  | invoker_.AsyncInvoke<void>( | 
|  | RTC_FROM_HERE, signaling_thread_, | 
|  | rtc::Bind(&QuicDataChannel::OnBufferedAmountChange_s, this, | 
|  | buffered_amount)); | 
|  | } | 
|  |  | 
|  | void QuicDataChannel::Close() { | 
|  | RTC_DCHECK(signaling_thread_->IsCurrent()); | 
|  | if (state_ == kClosed || state_ == kClosing) { | 
|  | return; | 
|  | } | 
|  | LOG(LS_INFO) << "Closing QUIC data channel."; | 
|  | SetState_s(kClosing); | 
|  | worker_thread_->Invoke<void>(RTC_FROM_HERE, | 
|  | rtc::Bind(&QuicDataChannel::Close_w, this)); | 
|  | SetState_s(kClosed); | 
|  | } | 
|  |  | 
|  | void QuicDataChannel::Close_w() { | 
|  | RTC_DCHECK(worker_thread_->IsCurrent()); | 
|  | for (auto& kv : incoming_quic_messages_) { | 
|  | Message& message = kv.second; | 
|  | cricket::ReliableQuicStream* stream = message.stream; | 
|  | stream->Close(); | 
|  | } | 
|  |  | 
|  | for (auto& kv : write_blocked_quic_streams_) { | 
|  | cricket::ReliableQuicStream* stream = kv.second; | 
|  | stream->Close(); | 
|  | } | 
|  | } | 
|  |  | 
|  | bool QuicDataChannel::SetTransportChannel( | 
|  | cricket::QuicTransportChannel* channel) { | 
|  | RTC_DCHECK(signaling_thread_->IsCurrent()); | 
|  |  | 
|  | if (!channel) { | 
|  | LOG(LS_ERROR) << "|channel| is NULL. Cannot set transport channel."; | 
|  | return false; | 
|  | } | 
|  | if (quic_transport_channel_) { | 
|  | if (channel == quic_transport_channel_) { | 
|  | LOG(LS_WARNING) << "Ignoring duplicate transport channel."; | 
|  | return true; | 
|  | } | 
|  | LOG(LS_ERROR) << "|channel| does not match existing transport channel."; | 
|  | return false; | 
|  | } | 
|  |  | 
|  | quic_transport_channel_ = channel; | 
|  | LOG(LS_INFO) << "Setting QuicTransportChannel for QUIC data channel " << id_; | 
|  | DataState data_channel_state = worker_thread_->Invoke<DataState>( | 
|  | RTC_FROM_HERE, rtc::Bind(&QuicDataChannel::SetTransportChannel_w, this)); | 
|  | SetState_s(data_channel_state); | 
|  | return true; | 
|  | } | 
|  |  | 
|  | DataChannelInterface::DataState QuicDataChannel::SetTransportChannel_w() { | 
|  | RTC_DCHECK(worker_thread_->IsCurrent()); | 
|  | quic_transport_channel_->SignalReadyToSend.connect( | 
|  | this, &QuicDataChannel::OnReadyToSend); | 
|  | quic_transport_channel_->SignalClosed.connect( | 
|  | this, &QuicDataChannel::OnConnectionClosed); | 
|  | if (quic_transport_channel_->writable()) { | 
|  | return kOpen; | 
|  | } | 
|  | return kConnecting; | 
|  | } | 
|  |  | 
|  | void QuicDataChannel::OnIncomingMessage(Message&& message) { | 
|  | RTC_DCHECK(network_thread_->IsCurrent()); | 
|  | RTC_DCHECK(message.stream); | 
|  | if (!observer_) { | 
|  | LOG(LS_WARNING) << "QUIC data channel " << id_ | 
|  | << " received a message but has no observer."; | 
|  | message.stream->Close(); | 
|  | return; | 
|  | } | 
|  | // A FIN is received if the message fits into a single QUIC stream frame and | 
|  | // the remote peer is done sending. | 
|  | if (message.stream->fin_received()) { | 
|  | LOG(LS_INFO) << "Stream " << message.stream->id() | 
|  | << " has finished receiving data for QUIC data channel " | 
|  | << id_; | 
|  | DataBuffer final_message(message.buffer, false); | 
|  | invoker_.AsyncInvoke<void>(RTC_FROM_HERE, signaling_thread_, | 
|  | rtc::Bind(&QuicDataChannel::OnMessage_s, this, | 
|  | std::move(final_message))); | 
|  | message.stream->Close(); | 
|  | return; | 
|  | } | 
|  | // Otherwise the message is divided across multiple QUIC stream frames, so | 
|  | // queue the data. OnDataReceived() will be called each time the remaining | 
|  | // QUIC stream frames arrive. | 
|  | LOG(LS_INFO) << "QUIC data channel " << id_ | 
|  | << " is queuing incoming data for stream " | 
|  | << message.stream->id(); | 
|  | incoming_quic_messages_[message.stream->id()] = std::move(message); | 
|  | message.stream->SignalDataReceived.connect(this, | 
|  | &QuicDataChannel::OnDataReceived); | 
|  | // The QUIC stream will be removed from |incoming_quic_messages_| once it | 
|  | // closes. | 
|  | message.stream->SignalClosed.connect( | 
|  | this, &QuicDataChannel::OnIncomingQueuedStreamClosed); | 
|  | } | 
|  |  | 
|  | void QuicDataChannel::OnDataReceived(net::QuicStreamId stream_id, | 
|  | const char* data, | 
|  | size_t len) { | 
|  | RTC_DCHECK(network_thread_->IsCurrent()); | 
|  | RTC_DCHECK(data); | 
|  | const auto& kv = incoming_quic_messages_.find(stream_id); | 
|  | if (kv == incoming_quic_messages_.end()) { | 
|  | RTC_NOTREACHED(); | 
|  | return; | 
|  | } | 
|  | Message& message = kv->second; | 
|  | cricket::ReliableQuicStream* stream = message.stream; | 
|  | rtc::CopyOnWriteBuffer& received_data = message.buffer; | 
|  | // If the QUIC stream has not received a FIN, then the remote peer is not | 
|  | // finished sending data. | 
|  | if (!stream->fin_received()) { | 
|  | received_data.AppendData(data, len); | 
|  | return; | 
|  | } | 
|  | // Otherwise we are done receiving and can provide the data channel observer | 
|  | // with the message. | 
|  | LOG(LS_INFO) << "Stream " << stream_id | 
|  | << " has finished receiving data for QUIC data channel " << id_; | 
|  | received_data.AppendData(data, len); | 
|  | DataBuffer final_message(std::move(received_data), false); | 
|  | invoker_.AsyncInvoke<void>( | 
|  | RTC_FROM_HERE, signaling_thread_, | 
|  | rtc::Bind(&QuicDataChannel::OnMessage_s, this, std::move(final_message))); | 
|  | // Once the stream is closed, OnDataReceived will not fire for the stream. | 
|  | stream->Close(); | 
|  | } | 
|  |  | 
|  | void QuicDataChannel::OnReadyToSend(cricket::TransportChannel* channel) { | 
|  | RTC_DCHECK(network_thread_->IsCurrent()); | 
|  | RTC_DCHECK(channel == quic_transport_channel_); | 
|  | LOG(LS_INFO) << "QuicTransportChannel is ready to send"; | 
|  | invoker_.AsyncInvoke<void>( | 
|  | RTC_FROM_HERE, signaling_thread_, | 
|  | rtc::Bind(&QuicDataChannel::SetState_s, this, kOpen)); | 
|  | } | 
|  |  | 
|  | void QuicDataChannel::OnWriteBlockedStreamClosed(net::QuicStreamId stream_id, | 
|  | int error) { | 
|  | RTC_DCHECK(worker_thread_->IsCurrent()); | 
|  | LOG(LS_VERBOSE) << "Write blocked stream " << stream_id << " is closed."; | 
|  | write_blocked_quic_streams_.erase(stream_id); | 
|  | } | 
|  |  | 
|  | void QuicDataChannel::OnIncomingQueuedStreamClosed(net::QuicStreamId stream_id, | 
|  | int error) { | 
|  | RTC_DCHECK(network_thread_->IsCurrent()); | 
|  | LOG(LS_VERBOSE) << "Incoming queued stream " << stream_id << " is closed."; | 
|  | incoming_quic_messages_.erase(stream_id); | 
|  | } | 
|  |  | 
|  | void QuicDataChannel::OnConnectionClosed() { | 
|  | RTC_DCHECK(worker_thread_->IsCurrent()); | 
|  | invoker_.AsyncInvoke<void>(RTC_FROM_HERE, signaling_thread_, | 
|  | rtc::Bind(&QuicDataChannel::Close, this)); | 
|  | } | 
|  |  | 
|  | void QuicDataChannel::OnMessage_s(const DataBuffer& received_data) { | 
|  | RTC_DCHECK(signaling_thread_->IsCurrent()); | 
|  | if (observer_) { | 
|  | observer_->OnMessage(received_data); | 
|  | } | 
|  | } | 
|  |  | 
|  | void QuicDataChannel::SetState_s(DataState state) { | 
|  | RTC_DCHECK(signaling_thread_->IsCurrent()); | 
|  | if (state_ == state || state_ == kClosed) { | 
|  | return; | 
|  | } | 
|  | if (state_ == kClosing && state != kClosed) { | 
|  | return; | 
|  | } | 
|  | LOG(LS_INFO) << "Setting state to " << state << " for QUIC data channel " | 
|  | << id_; | 
|  | state_ = state; | 
|  | if (observer_) { | 
|  | observer_->OnStateChange(); | 
|  | } | 
|  | } | 
|  |  | 
|  | void QuicDataChannel::OnBufferedAmountChange_s(uint64_t buffered_amount) { | 
|  | RTC_DCHECK(signaling_thread_->IsCurrent()); | 
|  | if (observer_) { | 
|  | observer_->OnBufferedAmountChange(buffered_amount); | 
|  | } | 
|  | } | 
|  |  | 
|  | size_t QuicDataChannel::GetNumWriteBlockedStreams() const { | 
|  | return write_blocked_quic_streams_.size(); | 
|  | } | 
|  |  | 
|  | size_t QuicDataChannel::GetNumIncomingStreams() const { | 
|  | return incoming_quic_messages_.size(); | 
|  | } | 
|  |  | 
|  | }  // namespace webrtc |