net/quic/reliable_quic_stream.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "net/quic/reliable_quic_stream.h"
   6
   7 #include "base/logging.h"
   8 #include "base/profiler/scoped_tracker.h"
   9 #include "net/quic/iovector.h"
  10 #include "net/quic/quic_flow_controller.h"
  11 #include "net/quic/quic_session.h"
  12 #include "net/quic/quic_write_blocked_list.h"
  13
  14 using base::StringPiece;
  15 using std::min;
  16 using std::string;
  17
  18 namespace net {
  19
  20 #define ENDPOINT (is_server_ ? "Server: " : " Client: ")
  21
  22 namespace {
  23
  24 struct iovec MakeIovec(StringPiece data) {
  25   struct iovec iov = {const_cast<char*>(data.data()),
  26                       static_cast<size_t>(data.size())};
  27   return iov;
  28 }
  29
  30 size_t GetInitialStreamFlowControlWindowToSend(QuicSession* session) {
  31   return session->config()->GetInitialStreamFlowControlWindowToSend();
  32 }
  33
  34 size_t GetReceivedFlowControlWindow(QuicSession* session) {
  35   if (session->config()->HasReceivedInitialStreamFlowControlWindowBytes()) {
  36     return session->config()->ReceivedInitialStreamFlowControlWindowBytes();
  37   }
  38
  39   return kMinimumFlowControlSendWindow;
  40 }
  41
  42 }  // namespace
  43
  44 // Wrapper that aggregates OnAckNotifications for packets sent using
  45 // WriteOrBufferData and delivers them to the original
  46 // QuicAckNotifier::DelegateInterface after all bytes written using
  47 // WriteOrBufferData are acked.  This level of indirection is
  48 // necessary because the delegate interface provides no mechanism that
  49 // WriteOrBufferData can use to inform it that the write required
  50 // multiple WritevData calls or that only part of the data has been
  51 // sent out by the time ACKs start arriving.
  52 class ReliableQuicStream::ProxyAckNotifierDelegate
  53     : public QuicAckNotifier::DelegateInterface {
  54  public:
  55   explicit ProxyAckNotifierDelegate(DelegateInterface* delegate)
  56       : delegate_(delegate),
  57         pending_acks_(0),
  58         wrote_last_data_(false),
  59         num_retransmitted_packets_(0),
  60         num_retransmitted_bytes_(0) {
  61   }
  62
  63   void OnAckNotification(int num_retransmitted_packets,
  64                          int num_retransmitted_bytes,
  65                          QuicTime::Delta delta_largest_observed) override {
  66     DCHECK_LT(0, pending_acks_);
  67     --pending_acks_;
  68     num_retransmitted_packets_ += num_retransmitted_packets;
  69     num_retransmitted_bytes_ += num_retransmitted_bytes;
  70
  71     if (wrote_last_data_ && pending_acks_ == 0) {
  72       delegate_->OnAckNotification(num_retransmitted_packets_,
  73                                    num_retransmitted_bytes_,
  74                                    delta_largest_observed);
  75     }
  76   }
  77
  78   void WroteData(bool last_data) {
  79     DCHECK(!wrote_last_data_);
  80     ++pending_acks_;
  81     wrote_last_data_ = last_data;
  82   }
  83
  84  protected:
  85   // Delegates are ref counted.
  86   ~ProxyAckNotifierDelegate() override {}
  87
  88  private:
  89   // Original delegate.  delegate_->OnAckNotification will be called when:
  90   //   wrote_last_data_ == true and pending_acks_ == 0
  91   scoped_refptr<DelegateInterface> delegate_;
  92
  93   // Number of outstanding acks.
  94   int pending_acks_;
  95
  96   // True if no pending writes remain.
  97   bool wrote_last_data_;
  98
  99   // Accumulators.
 100   int num_original_packets_;
 101   int num_original_bytes_;
 102   int num_retransmitted_packets_;
 103   int num_retransmitted_bytes_;
 104
 105   DISALLOW_COPY_AND_ASSIGN(ProxyAckNotifierDelegate);
 106 };
 107
 108 ReliableQuicStream::PendingData::PendingData(
 109     string data_in, scoped_refptr<ProxyAckNotifierDelegate> delegate_in)
 110     : data(data_in), delegate(delegate_in) {
 111 }
 112
 113 ReliableQuicStream::PendingData::~PendingData() {
 114 }
 115
 116 ReliableQuicStream::ReliableQuicStream(QuicStreamId id, QuicSession* session)
 117     : sequencer_(this),
 118       id_(id),
 119       session_(session),
 120       stream_bytes_read_(0),
 121       stream_bytes_written_(0),
 122       stream_error_(QUIC_STREAM_NO_ERROR),
 123       connection_error_(QUIC_NO_ERROR),
 124       read_side_closed_(false),
 125       write_side_closed_(false),
 126       fin_buffered_(false),
 127       fin_sent_(false),
 128       fin_received_(false),
 129       rst_sent_(false),
 130       rst_received_(false),
 131       fec_policy_(FEC_PROTECT_OPTIONAL),
 132       is_server_(session_->is_server()),
 133       flow_controller_(
 134           session_->connection(), id_, is_server_,
 135           GetReceivedFlowControlWindow(session),
 136           GetInitialStreamFlowControlWindowToSend(session),
 137           GetInitialStreamFlowControlWindowToSend(session)),
 138       connection_flow_controller_(session_->flow_controller()),
 139       stream_contributes_to_connection_flow_control_(true) {
 140 }
 141
 142 ReliableQuicStream::~ReliableQuicStream() {
 143 }
 144
 145 void ReliableQuicStream::OnStreamFrame(const QuicStreamFrame& frame) {
 146   if (read_side_closed_) {
 147     DVLOG(1) << ENDPOINT << "Ignoring frame " << frame.stream_id;
 148     // We don't want to be reading: blackhole the data.
 149     return;
 150   }
 151
 152   if (frame.stream_id != id_) {
 153     session_->connection()->SendConnectionClose(QUIC_INTERNAL_ERROR);
 154     return;
 155   }
 156
 157   if (frame.fin) {
 158     fin_received_ = true;
 159   }
 160
 161   // This count include duplicate data received.
 162   size_t frame_payload_size = frame.data.TotalBufferSize();
 163   stream_bytes_read_ += frame_payload_size;
 164
 165   // Flow control is interested in tracking highest received offset.
 166   if (MaybeIncreaseHighestReceivedOffset(frame.offset + frame_payload_size)) {
 167     // As the highest received offset has changed, we should check to see if
 168     // this is a violation of flow control.
 169     if (flow_controller_.FlowControlViolation() ||
 170         connection_flow_controller_->FlowControlViolation()) {
 171       session_->connection()->SendConnectionClose(
 172           QUIC_FLOW_CONTROL_RECEIVED_TOO_MUCH_DATA);
 173       return;
 174     }
 175   }
 176
 177   sequencer_.OnStreamFrame(frame);
 178 }
 179
 180 int ReliableQuicStream::num_frames_received() const {
 181   return sequencer_.num_frames_received();
 182 }
 183
 184 int ReliableQuicStream::num_early_frames_received() const {
 185   return sequencer_.num_early_frames_received();
 186 }
 187
 188 int ReliableQuicStream::num_duplicate_frames_received() const {
 189   return sequencer_.num_duplicate_frames_received();
 190 }
 191
 192 void ReliableQuicStream::OnStreamReset(const QuicRstStreamFrame& frame) {
 193   rst_received_ = true;
 194   MaybeIncreaseHighestReceivedOffset(frame.byte_offset);
 195
 196   stream_error_ = frame.error_code;
 197   CloseWriteSide();
 198   CloseReadSide();
 199 }
 200
 201 void ReliableQuicStream::OnConnectionClosed(QuicErrorCode error,
 202                                             bool from_peer) {
 203   if (read_side_closed_ && write_side_closed_) {
 204     return;
 205   }
 206   if (error != QUIC_NO_ERROR) {
 207     stream_error_ = QUIC_STREAM_CONNECTION_ERROR;
 208     connection_error_ = error;
 209   }
 210
 211   CloseWriteSide();
 212   CloseReadSide();
 213 }
 214
 215 void ReliableQuicStream::OnFinRead() {
 216   DCHECK(sequencer_.IsClosed());
 217   fin_received_ = true;
 218   CloseReadSide();
 219 }
 220
 221 void ReliableQuicStream::Reset(QuicRstStreamErrorCode error) {
 222   DCHECK_NE(QUIC_STREAM_NO_ERROR, error);
 223   stream_error_ = error;
 224   // Sending a RstStream results in calling CloseStream.
 225   session()->SendRstStream(id(), error, stream_bytes_written_);
 226   rst_sent_ = true;
 227 }
 228
 229 void ReliableQuicStream::CloseConnection(QuicErrorCode error) {
 230   // TODO(vadimt): Remove ScopedTracker below once crbug.com/422516 is fixed.
 231   tracked_objects::ScopedTracker tracking_profile(
 232       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 233           "422516 ReliableQuicStream::CloseConnection"));
 234
 235   session()->connection()->SendConnectionClose(error);
 236 }
 237
 238 void ReliableQuicStream::CloseConnectionWithDetails(QuicErrorCode error,
 239                                                     const string& details) {
 240   session()->connection()->SendConnectionCloseWithDetails(error, details);
 241 }
 242
 243 QuicVersion ReliableQuicStream::version() const {
 244   return session()->connection()->version();
 245 }
 246
 247 void ReliableQuicStream::WriteOrBufferData(
 248     StringPiece data,
 249     bool fin,
 250     QuicAckNotifier::DelegateInterface* ack_notifier_delegate) {
 251   if (data.empty() && !fin) {
 252     LOG(DFATAL) << "data.empty() && !fin";
 253     return;
 254   }
 255
 256   if (fin_buffered_) {
 257     LOG(DFATAL) << "Fin already buffered";
 258     return;
 259   }
 260
 261   scoped_refptr<ProxyAckNotifierDelegate> proxy_delegate;
 262   if (ack_notifier_delegate != nullptr) {
 263     proxy_delegate = new ProxyAckNotifierDelegate(ack_notifier_delegate);
 264   }
 265
 266   QuicConsumedData consumed_data(0, false);
 267   fin_buffered_ = fin;
 268
 269   if (queued_data_.empty()) {
 270     struct iovec iov(MakeIovec(data));
 271     consumed_data = WritevData(&iov, 1, fin, proxy_delegate.get());
 272     DCHECK_LE(consumed_data.bytes_consumed, data.length());
 273   }
 274
 275   bool write_completed;
 276   // If there's unconsumed data or an unconsumed fin, queue it.
 277   if (consumed_data.bytes_consumed < data.length() ||
 278       (fin && !consumed_data.fin_consumed)) {
 279     StringPiece remainder(data.substr(consumed_data.bytes_consumed));
 280     queued_data_.push_back(PendingData(remainder.as_string(), proxy_delegate));
 281     write_completed = false;
 282   } else {
 283     write_completed = true;
 284   }
 285
 286   if ((proxy_delegate.get() != nullptr) &&
 287       (consumed_data.bytes_consumed > 0 || consumed_data.fin_consumed)) {
 288     proxy_delegate->WroteData(write_completed);
 289   }
 290 }
 291
 292 void ReliableQuicStream::OnCanWrite() {
 293   bool fin = false;
 294   while (!queued_data_.empty()) {
 295     PendingData* pending_data = &queued_data_.front();
 296     ProxyAckNotifierDelegate* delegate = pending_data->delegate.get();
 297     if (queued_data_.size() == 1 && fin_buffered_) {
 298       fin = true;
 299     }
 300     struct iovec iov(MakeIovec(pending_data->data));
 301     QuicConsumedData consumed_data = WritevData(&iov, 1, fin, delegate);
 302     if (consumed_data.bytes_consumed == pending_data->data.size() &&
 303         fin == consumed_data.fin_consumed) {
 304       queued_data_.pop_front();
 305       if (delegate != nullptr) {
 306         delegate->WroteData(true);
 307       }
 308     } else {
 309       if (consumed_data.bytes_consumed > 0) {
 310         pending_data->data.erase(0, consumed_data.bytes_consumed);
 311         if (delegate != nullptr) {
 312           delegate->WroteData(false);
 313         }
 314       }
 315       break;
 316     }
 317   }
 318 }
 319
 320 void ReliableQuicStream::MaybeSendBlocked() {
 321   flow_controller_.MaybeSendBlocked();
 322   if (!stream_contributes_to_connection_flow_control_) {
 323     return;
 324   }
 325   connection_flow_controller_->MaybeSendBlocked();
 326   // If we are connection level flow control blocked, then add the stream
 327   // to the write blocked list. It will be given a chance to write when a
 328   // connection level WINDOW_UPDATE arrives.
 329   if (connection_flow_controller_->IsBlocked() &&
 330       !flow_controller_.IsBlocked()) {
 331     session_->MarkWriteBlocked(id(), EffectivePriority());
 332   }
 333 }
 334
 335 QuicConsumedData ReliableQuicStream::WritevData(
 336     const struct iovec* iov,
 337     int iov_count,
 338     bool fin,
 339     QuicAckNotifier::DelegateInterface* ack_notifier_delegate) {
 340   if (write_side_closed_) {
 341     DLOG(ERROR) << ENDPOINT << "Attempt to write when the write side is closed";
 342     return QuicConsumedData(0, false);
 343   }
 344
 345   // How much data we want to write.
 346   size_t write_length = TotalIovecLength(iov, iov_count);
 347
 348   // A FIN with zero data payload should not be flow control blocked.
 349   bool fin_with_zero_data = (fin && write_length == 0);
 350
 351   if (flow_controller_.IsEnabled()) {
 352     // How much data we are allowed to write from flow control.
 353     QuicByteCount send_window = flow_controller_.SendWindowSize();
 354     if (stream_contributes_to_connection_flow_control_) {
 355       send_window =
 356           min(send_window, connection_flow_controller_->SendWindowSize());
 357     }
 358
 359     if (send_window == 0 && !fin_with_zero_data) {
 360       // Quick return if we can't send anything.
 361       MaybeSendBlocked();
 362       return QuicConsumedData(0, false);
 363     }
 364
 365     if (write_length > send_window) {
 366       // Don't send the FIN if we aren't going to send all the data.
 367       fin = false;
 368
 369       // Writing more data would be a violation of flow control.
 370       write_length = static_cast<size_t>(send_window);
 371     }
 372   }
 373
 374   // Fill an IOVector with bytes from the iovec.
 375   IOVector data;
 376   data.AppendIovecAtMostBytes(iov, iov_count, write_length);
 377
 378   QuicConsumedData consumed_data = session()->WritevData(
 379       id(), data, stream_bytes_written_, fin, GetFecProtection(),
 380       ack_notifier_delegate);
 381   stream_bytes_written_ += consumed_data.bytes_consumed;
 382
 383   AddBytesSent(consumed_data.bytes_consumed);
 384
 385   if (consumed_data.bytes_consumed == write_length) {
 386     if (!fin_with_zero_data) {
 387       MaybeSendBlocked();
 388     }
 389     if (fin && consumed_data.fin_consumed) {
 390       fin_sent_ = true;
 391       CloseWriteSide();
 392     } else if (fin && !consumed_data.fin_consumed) {
 393       session_->MarkWriteBlocked(id(), EffectivePriority());
 394     }
 395   } else {
 396     session_->MarkWriteBlocked(id(), EffectivePriority());
 397   }
 398   return consumed_data;
 399 }
 400
 401 FecProtection ReliableQuicStream::GetFecProtection() {
 402   return fec_policy_ == FEC_PROTECT_ALWAYS ? MUST_FEC_PROTECT : MAY_FEC_PROTECT;
 403 }
 404
 405 void ReliableQuicStream::CloseReadSide() {
 406   if (read_side_closed_) {
 407     return;
 408   }
 409   DVLOG(1) << ENDPOINT << "Done reading from stream " << id();
 410
 411   read_side_closed_ = true;
 412   if (write_side_closed_) {
 413     DVLOG(1) << ENDPOINT << "Closing stream: " << id();
 414     session_->CloseStream(id());
 415   }
 416 }
 417
 418 void ReliableQuicStream::CloseWriteSide() {
 419   if (write_side_closed_) {
 420     return;
 421   }
 422   DVLOG(1) << ENDPOINT << "Done writing to stream " << id();
 423
 424   write_side_closed_ = true;
 425   if (read_side_closed_) {
 426     DVLOG(1) << ENDPOINT << "Closing stream: " << id();
 427     session_->CloseStream(id());
 428   }
 429 }
 430
 431 bool ReliableQuicStream::HasBufferedData() const {
 432   return !queued_data_.empty();
 433 }
 434
 435 void ReliableQuicStream::OnClose() {
 436   CloseReadSide();
 437   CloseWriteSide();
 438
 439   if (!fin_sent_ && !rst_sent_) {
 440     // For flow control accounting, we must tell the peer how many bytes we have
 441     // written on this stream before termination. Done here if needed, using a
 442     // RST frame.
 443     DVLOG(1) << ENDPOINT << "Sending RST in OnClose: " << id();
 444     session_->SendRstStream(id(), QUIC_RST_ACKNOWLEDGEMENT,
 445                             stream_bytes_written_);
 446     rst_sent_ = true;
 447   }
 448
 449   // We are closing the stream and will not process any further incoming bytes.
 450   // As there may be more bytes in flight and we need to ensure that both
 451   // endpoints have the same connection level flow control state, mark all
 452   // unreceived or buffered bytes as consumed.
 453   QuicByteCount bytes_to_consume =
 454       flow_controller_.highest_received_byte_offset() -
 455       flow_controller_.bytes_consumed();
 456   AddBytesConsumed(bytes_to_consume);
 457 }
 458
 459 void ReliableQuicStream::OnWindowUpdateFrame(
 460     const QuicWindowUpdateFrame& frame) {
 461   if (!flow_controller_.IsEnabled()) {
 462     DLOG(DFATAL) << "Flow control not enabled! " << version();
 463     return;
 464   }
 465   if (flow_controller_.UpdateSendWindowOffset(frame.byte_offset)) {
 466     // We can write again!
 467     // TODO(rjshade): This does not respect priorities (e.g. multiple
 468     //                outstanding POSTs are unblocked on arrival of
 469     //                SHLO with initial window).
 470     // As long as the connection is not flow control blocked, we can write!
 471     OnCanWrite();
 472   }
 473 }
 474
 475 bool ReliableQuicStream::MaybeIncreaseHighestReceivedOffset(
 476     QuicStreamOffset new_offset) {
 477   if (!flow_controller_.IsEnabled()) {
 478     return false;
 479   }
 480   uint64 increment =
 481       new_offset - flow_controller_.highest_received_byte_offset();
 482   if (!flow_controller_.UpdateHighestReceivedOffset(new_offset)) {
 483     return false;
 484   }
 485
 486   // If |new_offset| increased the stream flow controller's highest received
 487   // offset, then we need to increase the connection flow controller's value
 488   // by the incremental difference.
 489   if (stream_contributes_to_connection_flow_control_) {
 490     connection_flow_controller_->UpdateHighestReceivedOffset(
 491         connection_flow_controller_->highest_received_byte_offset() +
 492         increment);
 493   }
 494   return true;
 495 }
 496
 497 void ReliableQuicStream::AddBytesSent(QuicByteCount bytes) {
 498   if (flow_controller_.IsEnabled()) {
 499     flow_controller_.AddBytesSent(bytes);
 500     if (stream_contributes_to_connection_flow_control_) {
 501       connection_flow_controller_->AddBytesSent(bytes);
 502     }
 503   }
 504 }
 505
 506 void ReliableQuicStream::AddBytesConsumed(QuicByteCount bytes) {
 507   if (flow_controller_.IsEnabled()) {
 508     // Only adjust stream level flow controller if we are still reading.
 509     if (!read_side_closed_) {
 510       flow_controller_.AddBytesConsumed(bytes);
 511     }
 512
 513     if (stream_contributes_to_connection_flow_control_) {
 514       connection_flow_controller_->AddBytesConsumed(bytes);
 515     }
 516   }
 517 }
 518
 519 void ReliableQuicStream::UpdateSendWindowOffset(QuicStreamOffset new_window) {
 520   if (flow_controller_.UpdateSendWindowOffset(new_window)) {
 521     OnCanWrite();
 522   }
 523 }
 524
 525 bool ReliableQuicStream::IsFlowControlBlocked() {
 526   if (flow_controller_.IsBlocked()) {
 527     return true;
 528   }
 529   return stream_contributes_to_connection_flow_control_ &&
 530       connection_flow_controller_->IsBlocked();
 531 }
 532
 533 }  // namespace net