src/net/tools/quic/quic_server_session.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/tools/quic/quic_server_session.h"
   6
   7 #include "base/logging.h"
   8 #include "net/quic/crypto/source_address_token.h"
   9 #include "net/quic/quic_connection.h"
  10 #include "net/quic/quic_flags.h"
  11 #include "net/quic/reliable_quic_stream.h"
  12 #include "net/tools/quic/quic_spdy_server_stream.h"
  13
  14 namespace net {
  15 namespace tools {
  16
  17 QuicServerSession::QuicServerSession(const QuicConfig& config,
  18                                      QuicConnection* connection,
  19                                      QuicServerSessionVisitor* visitor,
  20                                      bool is_secure)
  21     : QuicSession(connection, config, is_secure),
  22       visitor_(visitor),
  23       bandwidth_estimate_sent_to_client_(QuicBandwidth::Zero()),
  24       last_scup_time_(QuicTime::Zero()),
  25       last_scup_sequence_number_(0) {}
  26
  27 QuicServerSession::~QuicServerSession() {}
  28
  29 void QuicServerSession::InitializeSession(
  30     const QuicCryptoServerConfig& crypto_config) {
  31   QuicSession::InitializeSession();
  32   crypto_stream_.reset(CreateQuicCryptoServerStream(crypto_config));
  33 }
  34
  35 QuicCryptoServerStream* QuicServerSession::CreateQuicCryptoServerStream(
  36     const QuicCryptoServerConfig& crypto_config) {
  37   return new QuicCryptoServerStream(crypto_config, this);
  38 }
  39
  40 void QuicServerSession::OnConfigNegotiated() {
  41   QuicSession::OnConfigNegotiated();
  42   if (!FLAGS_enable_quic_fec ||
  43       !config()->HasReceivedConnectionOptions() ||
  44       !net::ContainsQuicTag(config()->ReceivedConnectionOptions(), kFHDR)) {
  45     return;
  46   }
  47   // kFHDR config maps to FEC protection always for headers stream.
  48   // TODO(jri): Add crypto stream in addition to headers for kHDR.
  49   headers_stream_->set_fec_policy(FEC_PROTECT_ALWAYS);
  50 }
  51
  52 void QuicServerSession::OnConnectionClosed(QuicErrorCode error,
  53                                            bool from_peer) {
  54   QuicSession::OnConnectionClosed(error, from_peer);
  55   // In the unlikely event we get a connection close while doing an asynchronous
  56   // crypto event, make sure we cancel the callback.
  57   if (crypto_stream_.get() != nullptr) {
  58     crypto_stream_->CancelOutstandingCallbacks();
  59   }
  60   visitor_->OnConnectionClosed(connection()->connection_id(), error);
  61 }
  62
  63 void QuicServerSession::OnWriteBlocked() {
  64   QuicSession::OnWriteBlocked();
  65   visitor_->OnWriteBlocked(connection());
  66 }
  67
  68 void QuicServerSession::OnCongestionWindowChange(QuicTime now) {
  69   if (connection()->version() <= QUIC_VERSION_21) {
  70     return;
  71   }
  72
  73   // If not enough time has passed since the last time we sent an update to the
  74   // client, or not enough packets have been sent, then return early.
  75   const QuicSentPacketManager& sent_packet_manager =
  76       connection()->sent_packet_manager();
  77   int64 srtt_ms =
  78       sent_packet_manager.GetRttStats()->smoothed_rtt().ToMilliseconds();
  79   int64 now_ms = now.Subtract(last_scup_time_).ToMilliseconds();
  80   int64 packets_since_last_scup =
  81       connection()->sequence_number_of_last_sent_packet() -
  82       last_scup_sequence_number_;
  83   if (now_ms < (kMinIntervalBetweenServerConfigUpdatesRTTs * srtt_ms) ||
  84       now_ms < kMinIntervalBetweenServerConfigUpdatesMs ||
  85       packets_since_last_scup < kMinPacketsBetweenServerConfigUpdates) {
  86     return;
  87   }
  88
  89   // If the bandwidth recorder does not have a valid estimate, return early.
  90   const QuicSustainedBandwidthRecorder& bandwidth_recorder =
  91       sent_packet_manager.SustainedBandwidthRecorder();
  92   if (!bandwidth_recorder.HasEstimate()) {
  93     return;
  94   }
  95
  96   // The bandwidth recorder has recorded at least one sustained bandwidth
  97   // estimate. Check that it's substantially different from the last one that
  98   // we sent to the client, and if so, send the new one.
  99   QuicBandwidth new_bandwidth_estimate = bandwidth_recorder.BandwidthEstimate();
 100
 101   int64 bandwidth_delta =
 102       std::abs(new_bandwidth_estimate.ToBitsPerSecond() -
 103                bandwidth_estimate_sent_to_client_.ToBitsPerSecond());
 104
 105   // Define "substantial" difference as a 50% increase or decrease from the
 106   // last estimate.
 107   bool substantial_difference =
 108       bandwidth_delta >
 109       0.5 * bandwidth_estimate_sent_to_client_.ToBitsPerSecond();
 110   if (!substantial_difference) {
 111     return;
 112   }
 113
 114   bandwidth_estimate_sent_to_client_ = new_bandwidth_estimate;
 115   DVLOG(1) << "Server: sending new bandwidth estimate (KBytes/s): "
 116            << bandwidth_estimate_sent_to_client_.ToKBytesPerSecond();
 117
 118   // Include max bandwidth in the update.
 119   QuicBandwidth max_bandwidth_estimate =
 120       bandwidth_recorder.MaxBandwidthEstimate();
 121   int32 max_bandwidth_timestamp = bandwidth_recorder.MaxBandwidthTimestamp();
 122
 123   // Fill the proto before passing it to the crypto stream to send.
 124   CachedNetworkParameters cached_network_params;
 125   cached_network_params.set_bandwidth_estimate_bytes_per_second(
 126       bandwidth_estimate_sent_to_client_.ToBytesPerSecond());
 127   cached_network_params.set_max_bandwidth_estimate_bytes_per_second(
 128       max_bandwidth_estimate.ToBytesPerSecond());
 129   cached_network_params.set_max_bandwidth_timestamp_seconds(
 130       max_bandwidth_timestamp);
 131   cached_network_params.set_min_rtt_ms(
 132       sent_packet_manager.GetRttStats()->min_rtt().ToMilliseconds());
 133   cached_network_params.set_previous_connection_state(
 134       bandwidth_recorder.EstimateRecordedDuringSlowStart()
 135           ? CachedNetworkParameters::SLOW_START
 136           : CachedNetworkParameters::CONGESTION_AVOIDANCE);
 137   cached_network_params.set_timestamp(
 138       connection()->clock()->WallNow().ToUNIXSeconds());
 139   if (!serving_region_.empty()) {
 140     cached_network_params.set_serving_region(serving_region_);
 141   }
 142
 143   crypto_stream_->SendServerConfigUpdate(&cached_network_params);
 144   last_scup_time_ = now;
 145   last_scup_sequence_number_ =
 146       connection()->sequence_number_of_last_sent_packet();
 147 }
 148
 149 bool QuicServerSession::ShouldCreateIncomingDataStream(QuicStreamId id) {
 150   if (id % 2 == 0) {
 151     DVLOG(1) << "Invalid incoming even stream_id:" << id;
 152     connection()->SendConnectionClose(QUIC_INVALID_STREAM_ID);
 153     return false;
 154   }
 155   if (GetNumOpenStreams() >= get_max_open_streams()) {
 156     DVLOG(1) << "Failed to create a new incoming stream with id:" << id
 157              << " Already " << GetNumOpenStreams() << " streams open (max "
 158              << get_max_open_streams() << ").";
 159     connection()->SendConnectionClose(QUIC_TOO_MANY_OPEN_STREAMS);
 160     return false;
 161   }
 162   return true;
 163 }
 164
 165 QuicDataStream* QuicServerSession::CreateIncomingDataStream(
 166     QuicStreamId id) {
 167   if (!ShouldCreateIncomingDataStream(id)) {
 168     return nullptr;
 169   }
 170
 171   return new QuicSpdyServerStream(id, this);
 172 }
 173
 174 QuicDataStream* QuicServerSession::CreateOutgoingDataStream() {
 175   DLOG(ERROR) << "Server push not yet supported";
 176   return nullptr;
 177 }
 178
 179 QuicCryptoServerStream* QuicServerSession::GetCryptoStream() {
 180   return crypto_stream_.get();
 181 }
 182
 183 }  // namespace tools
 184 }  // namespace net