net/spdy/spdy_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/spdy/spdy_session.h"
   6
   7 #include <algorithm>
   8 #include <map>
   9
  10 #include "base/basictypes.h"
  11 #include "base/bind.h"
  12 #include "base/compiler_specific.h"
  13 #include "base/logging.h"
  14 #include "base/message_loop/message_loop.h"
  15 #include "base/metrics/field_trial.h"
  16 #include "base/metrics/histogram.h"
  17 #include "base/metrics/sparse_histogram.h"
  18 #include "base/profiler/scoped_tracker.h"
  19 #include "base/stl_util.h"
  20 #include "base/strings/string_number_conversions.h"
  21 #include "base/strings/string_util.h"
  22 #include "base/strings/stringprintf.h"
  23 #include "base/strings/utf_string_conversions.h"
  24 #include "base/time/time.h"
  25 #include "base/values.h"
  26 #include "crypto/ec_private_key.h"
  27 #include "crypto/ec_signature_creator.h"
  28 #include "net/base/connection_type_histograms.h"
  29 #include "net/base/net_log.h"
  30 #include "net/base/net_util.h"
  31 #include "net/cert/asn1_util.h"
  32 #include "net/cert/cert_verify_result.h"
  33 #include "net/http/http_log_util.h"
  34 #include "net/http/http_network_session.h"
  35 #include "net/http/http_server_properties.h"
  36 #include "net/http/http_util.h"
  37 #include "net/http/transport_security_state.h"
  38 #include "net/socket/ssl_client_socket.h"
  39 #include "net/spdy/spdy_buffer_producer.h"
  40 #include "net/spdy/spdy_frame_builder.h"
  41 #include "net/spdy/spdy_http_utils.h"
  42 #include "net/spdy/spdy_protocol.h"
  43 #include "net/spdy/spdy_session_pool.h"
  44 #include "net/spdy/spdy_stream.h"
  45 #include "net/ssl/channel_id_service.h"
  46 #include "net/ssl/ssl_cipher_suite_names.h"
  47 #include "net/ssl/ssl_connection_status_flags.h"
  48
  49 namespace net {
  50
  51 namespace {
  52
  53 const int kReadBufferSize = 8 * 1024;
  54 const int kDefaultConnectionAtRiskOfLossSeconds = 10;
  55 const int kHungIntervalSeconds = 10;
  56
  57 // Minimum seconds that unclaimed pushed streams will be kept in memory.
  58 const int kMinPushedStreamLifetimeSeconds = 300;
  59
  60 scoped_ptr<base::ListValue> SpdyHeaderBlockToListValue(
  61     const SpdyHeaderBlock& headers,
  62     net::NetLog::LogLevel log_level) {
  63   scoped_ptr<base::ListValue> headers_list(new base::ListValue());
  64   for (SpdyHeaderBlock::const_iterator it = headers.begin();
  65        it != headers.end(); ++it) {
  66     headers_list->AppendString(
  67         it->first + ": " +
  68         ElideHeaderValueForNetLog(log_level, it->first, it->second));
  69   }
  70   return headers_list.Pass();
  71 }
  72
  73 base::Value* NetLogSpdySynStreamSentCallback(const SpdyHeaderBlock* headers,
  74                                              bool fin,
  75                                              bool unidirectional,
  76                                              SpdyPriority spdy_priority,
  77                                              SpdyStreamId stream_id,
  78                                              NetLog::LogLevel log_level) {
  79   base::DictionaryValue* dict = new base::DictionaryValue();
  80   dict->Set("headers",
  81             SpdyHeaderBlockToListValue(*headers, log_level).release());
  82   dict->SetBoolean("fin", fin);
  83   dict->SetBoolean("unidirectional", unidirectional);
  84   dict->SetInteger("priority", static_cast<int>(spdy_priority));
  85   dict->SetInteger("stream_id", stream_id);
  86   return dict;
  87 }
  88
  89 base::Value* NetLogSpdySynStreamReceivedCallback(
  90     const SpdyHeaderBlock* headers,
  91     bool fin,
  92     bool unidirectional,
  93     SpdyPriority spdy_priority,
  94     SpdyStreamId stream_id,
  95     SpdyStreamId associated_stream,
  96     NetLog::LogLevel log_level) {
  97   base::DictionaryValue* dict = new base::DictionaryValue();
  98   dict->Set("headers",
  99             SpdyHeaderBlockToListValue(*headers, log_level).release());
 100   dict->SetBoolean("fin", fin);
 101   dict->SetBoolean("unidirectional", unidirectional);
 102   dict->SetInteger("priority", static_cast<int>(spdy_priority));
 103   dict->SetInteger("stream_id", stream_id);
 104   dict->SetInteger("associated_stream", associated_stream);
 105   return dict;
 106 }
 107
 108 base::Value* NetLogSpdySynReplyOrHeadersReceivedCallback(
 109     const SpdyHeaderBlock* headers,
 110     bool fin,
 111     SpdyStreamId stream_id,
 112     NetLog::LogLevel log_level) {
 113   base::DictionaryValue* dict = new base::DictionaryValue();
 114   dict->Set("headers",
 115             SpdyHeaderBlockToListValue(*headers, log_level).release());
 116   dict->SetBoolean("fin", fin);
 117   dict->SetInteger("stream_id", stream_id);
 118   return dict;
 119 }
 120
 121 base::Value* NetLogSpdySessionCloseCallback(int net_error,
 122                                             const std::string* description,
 123                                             NetLog::LogLevel /* log_level */) {
 124   base::DictionaryValue* dict = new base::DictionaryValue();
 125   dict->SetInteger("net_error", net_error);
 126   dict->SetString("description", *description);
 127   return dict;
 128 }
 129
 130 base::Value* NetLogSpdySessionCallback(const HostPortProxyPair* host_pair,
 131                                        NetLog::LogLevel /* log_level */) {
 132   base::DictionaryValue* dict = new base::DictionaryValue();
 133   dict->SetString("host", host_pair->first.ToString());
 134   dict->SetString("proxy", host_pair->second.ToPacString());
 135   return dict;
 136 }
 137
 138 base::Value* NetLogSpdyInitializedCallback(NetLog::Source source,
 139                                            const NextProto protocol_version,
 140                                            NetLog::LogLevel /* log_level */) {
 141   base::DictionaryValue* dict = new base::DictionaryValue();
 142   if (source.IsValid()) {
 143     source.AddToEventParameters(dict);
 144   }
 145   dict->SetString("protocol",
 146                   SSLClientSocket::NextProtoToString(protocol_version));
 147   return dict;
 148 }
 149
 150 base::Value* NetLogSpdySettingsCallback(const HostPortPair& host_port_pair,
 151                                         bool clear_persisted,
 152                                         NetLog::LogLevel /* log_level */) {
 153   base::DictionaryValue* dict = new base::DictionaryValue();
 154   dict->SetString("host", host_port_pair.ToString());
 155   dict->SetBoolean("clear_persisted", clear_persisted);
 156   return dict;
 157 }
 158
 159 base::Value* NetLogSpdySettingCallback(SpdySettingsIds id,
 160                                        const SpdyMajorVersion protocol_version,
 161                                        SpdySettingsFlags flags,
 162                                        uint32 value,
 163                                        NetLog::LogLevel /* log_level */) {
 164   base::DictionaryValue* dict = new base::DictionaryValue();
 165   dict->SetInteger("id",
 166                    SpdyConstants::SerializeSettingId(protocol_version, id));
 167   dict->SetInteger("flags", flags);
 168   dict->SetInteger("value", value);
 169   return dict;
 170 }
 171
 172 base::Value* NetLogSpdySendSettingsCallback(
 173     const SettingsMap* settings,
 174     const SpdyMajorVersion protocol_version,
 175     NetLog::LogLevel /* log_level */) {
 176   base::DictionaryValue* dict = new base::DictionaryValue();
 177   base::ListValue* settings_list = new base::ListValue();
 178   for (SettingsMap::const_iterator it = settings->begin();
 179        it != settings->end(); ++it) {
 180     const SpdySettingsIds id = it->first;
 181     const SpdySettingsFlags flags = it->second.first;
 182     const uint32 value = it->second.second;
 183     settings_list->Append(new base::StringValue(base::StringPrintf(
 184         "[id:%u flags:%u value:%u]",
 185         SpdyConstants::SerializeSettingId(protocol_version, id),
 186         flags,
 187         value)));
 188   }
 189   dict->Set("settings", settings_list);
 190   return dict;
 191 }
 192
 193 base::Value* NetLogSpdyWindowUpdateFrameCallback(
 194     SpdyStreamId stream_id,
 195     uint32 delta,
 196     NetLog::LogLevel /* log_level */) {
 197   base::DictionaryValue* dict = new base::DictionaryValue();
 198   dict->SetInteger("stream_id", static_cast<int>(stream_id));
 199   dict->SetInteger("delta", delta);
 200   return dict;
 201 }
 202
 203 base::Value* NetLogSpdySessionWindowUpdateCallback(
 204     int32 delta,
 205     int32 window_size,
 206     NetLog::LogLevel /* log_level */) {
 207   base::DictionaryValue* dict = new base::DictionaryValue();
 208   dict->SetInteger("delta", delta);
 209   dict->SetInteger("window_size", window_size);
 210   return dict;
 211 }
 212
 213 base::Value* NetLogSpdyDataCallback(SpdyStreamId stream_id,
 214                                     int size,
 215                                     bool fin,
 216                                     NetLog::LogLevel /* log_level */) {
 217   base::DictionaryValue* dict = new base::DictionaryValue();
 218   dict->SetInteger("stream_id", static_cast<int>(stream_id));
 219   dict->SetInteger("size", size);
 220   dict->SetBoolean("fin", fin);
 221   return dict;
 222 }
 223
 224 base::Value* NetLogSpdyRstCallback(SpdyStreamId stream_id,
 225                                    int status,
 226                                    const std::string* description,
 227                                    NetLog::LogLevel /* log_level */) {
 228   base::DictionaryValue* dict = new base::DictionaryValue();
 229   dict->SetInteger("stream_id", static_cast<int>(stream_id));
 230   dict->SetInteger("status", status);
 231   dict->SetString("description", *description);
 232   return dict;
 233 }
 234
 235 base::Value* NetLogSpdyPingCallback(SpdyPingId unique_id,
 236                                     bool is_ack,
 237                                     const char* type,
 238                                     NetLog::LogLevel /* log_level */) {
 239   base::DictionaryValue* dict = new base::DictionaryValue();
 240   dict->SetInteger("unique_id", static_cast<int>(unique_id));
 241   dict->SetString("type", type);
 242   dict->SetBoolean("is_ack", is_ack);
 243   return dict;
 244 }
 245
 246 base::Value* NetLogSpdyGoAwayCallback(SpdyStreamId last_stream_id,
 247                                       int active_streams,
 248                                       int unclaimed_streams,
 249                                       SpdyGoAwayStatus status,
 250                                       NetLog::LogLevel /* log_level */) {
 251   base::DictionaryValue* dict = new base::DictionaryValue();
 252   dict->SetInteger("last_accepted_stream_id",
 253                    static_cast<int>(last_stream_id));
 254   dict->SetInteger("active_streams", active_streams);
 255   dict->SetInteger("unclaimed_streams", unclaimed_streams);
 256   dict->SetInteger("status", static_cast<int>(status));
 257   return dict;
 258 }
 259
 260 base::Value* NetLogSpdyPushPromiseReceivedCallback(
 261     const SpdyHeaderBlock* headers,
 262     SpdyStreamId stream_id,
 263     SpdyStreamId promised_stream_id,
 264     NetLog::LogLevel log_level) {
 265   base::DictionaryValue* dict = new base::DictionaryValue();
 266   dict->Set("headers",
 267             SpdyHeaderBlockToListValue(*headers, log_level).release());
 268   dict->SetInteger("id", stream_id);
 269   dict->SetInteger("promised_stream_id", promised_stream_id);
 270   return dict;
 271 }
 272
 273 base::Value* NetLogSpdyAdoptedPushStreamCallback(
 274     SpdyStreamId stream_id, const GURL* url, NetLog::LogLevel log_level) {
 275   base::DictionaryValue* dict = new base::DictionaryValue();
 276   dict->SetInteger("stream_id", stream_id);
 277   dict->SetString("url", url->spec());
 278   return dict;
 279 }
 280
 281 // Helper function to return the total size of an array of objects
 282 // with .size() member functions.
 283 template <typename T, size_t N> size_t GetTotalSize(const T (&arr)[N]) {
 284   size_t total_size = 0;
 285   for (size_t i = 0; i < N; ++i) {
 286     total_size += arr[i].size();
 287   }
 288   return total_size;
 289 }
 290
 291 // Helper class for std:find_if on STL container containing
 292 // SpdyStreamRequest weak pointers.
 293 class RequestEquals {
 294  public:
 295   RequestEquals(const base::WeakPtr<SpdyStreamRequest>& request)
 296       : request_(request) {}
 297
 298   bool operator()(const base::WeakPtr<SpdyStreamRequest>& request) const {
 299     return request_.get() == request.get();
 300   }
 301
 302  private:
 303   const base::WeakPtr<SpdyStreamRequest> request_;
 304 };
 305
 306 // The maximum number of concurrent streams we will ever create.  Even if
 307 // the server permits more, we will never exceed this limit.
 308 const size_t kMaxConcurrentStreamLimit = 256;
 309
 310 }  // namespace
 311
 312 SpdyProtocolErrorDetails MapFramerErrorToProtocolError(
 313     SpdyFramer::SpdyError err) {
 314   switch(err) {
 315     case SpdyFramer::SPDY_NO_ERROR:
 316       return SPDY_ERROR_NO_ERROR;
 317     case SpdyFramer::SPDY_INVALID_CONTROL_FRAME:
 318       return SPDY_ERROR_INVALID_CONTROL_FRAME;
 319     case SpdyFramer::SPDY_CONTROL_PAYLOAD_TOO_LARGE:
 320       return SPDY_ERROR_CONTROL_PAYLOAD_TOO_LARGE;
 321     case SpdyFramer::SPDY_ZLIB_INIT_FAILURE:
 322       return SPDY_ERROR_ZLIB_INIT_FAILURE;
 323     case SpdyFramer::SPDY_UNSUPPORTED_VERSION:
 324       return SPDY_ERROR_UNSUPPORTED_VERSION;
 325     case SpdyFramer::SPDY_DECOMPRESS_FAILURE:
 326       return SPDY_ERROR_DECOMPRESS_FAILURE;
 327     case SpdyFramer::SPDY_COMPRESS_FAILURE:
 328       return SPDY_ERROR_COMPRESS_FAILURE;
 329     case SpdyFramer::SPDY_GOAWAY_FRAME_CORRUPT:
 330       return SPDY_ERROR_GOAWAY_FRAME_CORRUPT;
 331     case SpdyFramer::SPDY_RST_STREAM_FRAME_CORRUPT:
 332       return SPDY_ERROR_RST_STREAM_FRAME_CORRUPT;
 333     case SpdyFramer::SPDY_INVALID_DATA_FRAME_FLAGS:
 334       return SPDY_ERROR_INVALID_DATA_FRAME_FLAGS;
 335     case SpdyFramer::SPDY_INVALID_CONTROL_FRAME_FLAGS:
 336       return SPDY_ERROR_INVALID_CONTROL_FRAME_FLAGS;
 337     case SpdyFramer::SPDY_UNEXPECTED_FRAME:
 338       return SPDY_ERROR_UNEXPECTED_FRAME;
 339     default:
 340       NOTREACHED();
 341       return static_cast<SpdyProtocolErrorDetails>(-1);
 342   }
 343 }
 344
 345 Error MapFramerErrorToNetError(SpdyFramer::SpdyError err) {
 346   switch (err) {
 347     case SpdyFramer::SPDY_NO_ERROR:
 348       return OK;
 349     case SpdyFramer::SPDY_INVALID_CONTROL_FRAME:
 350       return ERR_SPDY_PROTOCOL_ERROR;
 351     case SpdyFramer::SPDY_CONTROL_PAYLOAD_TOO_LARGE:
 352       return ERR_SPDY_FRAME_SIZE_ERROR;
 353     case SpdyFramer::SPDY_ZLIB_INIT_FAILURE:
 354       return ERR_SPDY_COMPRESSION_ERROR;
 355     case SpdyFramer::SPDY_UNSUPPORTED_VERSION:
 356       return ERR_SPDY_PROTOCOL_ERROR;
 357     case SpdyFramer::SPDY_DECOMPRESS_FAILURE:
 358       return ERR_SPDY_COMPRESSION_ERROR;
 359     case SpdyFramer::SPDY_COMPRESS_FAILURE:
 360       return ERR_SPDY_COMPRESSION_ERROR;
 361     case SpdyFramer::SPDY_GOAWAY_FRAME_CORRUPT:
 362       return ERR_SPDY_PROTOCOL_ERROR;
 363     case SpdyFramer::SPDY_RST_STREAM_FRAME_CORRUPT:
 364       return ERR_SPDY_PROTOCOL_ERROR;
 365     case SpdyFramer::SPDY_INVALID_DATA_FRAME_FLAGS:
 366       return ERR_SPDY_PROTOCOL_ERROR;
 367     case SpdyFramer::SPDY_INVALID_CONTROL_FRAME_FLAGS:
 368       return ERR_SPDY_PROTOCOL_ERROR;
 369     case SpdyFramer::SPDY_UNEXPECTED_FRAME:
 370       return ERR_SPDY_PROTOCOL_ERROR;
 371     default:
 372       NOTREACHED();
 373       return ERR_SPDY_PROTOCOL_ERROR;
 374   }
 375 }
 376
 377 SpdyProtocolErrorDetails MapRstStreamStatusToProtocolError(
 378     SpdyRstStreamStatus status) {
 379   switch(status) {
 380     case RST_STREAM_PROTOCOL_ERROR:
 381       return STATUS_CODE_PROTOCOL_ERROR;
 382     case RST_STREAM_INVALID_STREAM:
 383       return STATUS_CODE_INVALID_STREAM;
 384     case RST_STREAM_REFUSED_STREAM:
 385       return STATUS_CODE_REFUSED_STREAM;
 386     case RST_STREAM_UNSUPPORTED_VERSION:
 387       return STATUS_CODE_UNSUPPORTED_VERSION;
 388     case RST_STREAM_CANCEL:
 389       return STATUS_CODE_CANCEL;
 390     case RST_STREAM_INTERNAL_ERROR:
 391       return STATUS_CODE_INTERNAL_ERROR;
 392     case RST_STREAM_FLOW_CONTROL_ERROR:
 393       return STATUS_CODE_FLOW_CONTROL_ERROR;
 394     case RST_STREAM_STREAM_IN_USE:
 395       return STATUS_CODE_STREAM_IN_USE;
 396     case RST_STREAM_STREAM_ALREADY_CLOSED:
 397       return STATUS_CODE_STREAM_ALREADY_CLOSED;
 398     case RST_STREAM_INVALID_CREDENTIALS:
 399       return STATUS_CODE_INVALID_CREDENTIALS;
 400     case RST_STREAM_FRAME_SIZE_ERROR:
 401       return STATUS_CODE_FRAME_SIZE_ERROR;
 402     case RST_STREAM_SETTINGS_TIMEOUT:
 403       return STATUS_CODE_SETTINGS_TIMEOUT;
 404     case RST_STREAM_CONNECT_ERROR:
 405       return STATUS_CODE_CONNECT_ERROR;
 406     case RST_STREAM_ENHANCE_YOUR_CALM:
 407       return STATUS_CODE_ENHANCE_YOUR_CALM;
 408     case RST_STREAM_INADEQUATE_SECURITY:
 409       return STATUS_CODE_INADEQUATE_SECURITY;
 410     case RST_STREAM_HTTP_1_1_REQUIRED:
 411       return STATUS_CODE_HTTP_1_1_REQUIRED;
 412     default:
 413       NOTREACHED();
 414       return static_cast<SpdyProtocolErrorDetails>(-1);
 415   }
 416 }
 417
 418 SpdyGoAwayStatus MapNetErrorToGoAwayStatus(Error err) {
 419   switch (err) {
 420     case OK:
 421       return GOAWAY_NO_ERROR;
 422     case ERR_SPDY_PROTOCOL_ERROR:
 423       return GOAWAY_PROTOCOL_ERROR;
 424     case ERR_SPDY_FLOW_CONTROL_ERROR:
 425       return GOAWAY_FLOW_CONTROL_ERROR;
 426     case ERR_SPDY_FRAME_SIZE_ERROR:
 427       return GOAWAY_FRAME_SIZE_ERROR;
 428     case ERR_SPDY_COMPRESSION_ERROR:
 429       return GOAWAY_COMPRESSION_ERROR;
 430     case ERR_SPDY_INADEQUATE_TRANSPORT_SECURITY:
 431       return GOAWAY_INADEQUATE_SECURITY;
 432     default:
 433       return GOAWAY_PROTOCOL_ERROR;
 434   }
 435 }
 436
 437 void SplitPushedHeadersToRequestAndResponse(const SpdyHeaderBlock& headers,
 438                                             SpdyMajorVersion protocol_version,
 439                                             SpdyHeaderBlock* request_headers,
 440                                             SpdyHeaderBlock* response_headers) {
 441   DCHECK(response_headers);
 442   DCHECK(request_headers);
 443   for (SpdyHeaderBlock::const_iterator it = headers.begin();
 444        it != headers.end();
 445        ++it) {
 446     SpdyHeaderBlock* to_insert = response_headers;
 447     if (protocol_version == SPDY2) {
 448       if (it->first == "url")
 449         to_insert = request_headers;
 450     } else {
 451       const char* host = protocol_version >= SPDY4 ? ":authority" : ":host";
 452       static const char scheme[] = ":scheme";
 453       static const char path[] = ":path";
 454       if (it->first == host || it->first == scheme || it->first == path)
 455         to_insert = request_headers;
 456     }
 457     to_insert->insert(*it);
 458   }
 459 }
 460
 461 SpdyStreamRequest::SpdyStreamRequest() : weak_ptr_factory_(this) {
 462   Reset();
 463 }
 464
 465 SpdyStreamRequest::~SpdyStreamRequest() {
 466   CancelRequest();
 467 }
 468
 469 int SpdyStreamRequest::StartRequest(
 470     SpdyStreamType type,
 471     const base::WeakPtr<SpdySession>& session,
 472     const GURL& url,
 473     RequestPriority priority,
 474     const BoundNetLog& net_log,
 475     const CompletionCallback& callback) {
 476   DCHECK(session);
 477   DCHECK(!session_);
 478   DCHECK(!stream_);
 479   DCHECK(callback_.is_null());
 480
 481   type_ = type;
 482   session_ = session;
 483   url_ = url;
 484   priority_ = priority;
 485   net_log_ = net_log;
 486   callback_ = callback;
 487
 488   base::WeakPtr<SpdyStream> stream;
 489   int rv = session->TryCreateStream(weak_ptr_factory_.GetWeakPtr(), &stream);
 490   if (rv == OK) {
 491     Reset();
 492     stream_ = stream;
 493   }
 494   return rv;
 495 }
 496
 497 void SpdyStreamRequest::CancelRequest() {
 498   if (session_)
 499     session_->CancelStreamRequest(weak_ptr_factory_.GetWeakPtr());
 500   Reset();
 501   // Do this to cancel any pending CompleteStreamRequest() tasks.
 502   weak_ptr_factory_.InvalidateWeakPtrs();
 503 }
 504
 505 base::WeakPtr<SpdyStream> SpdyStreamRequest::ReleaseStream() {
 506   DCHECK(!session_);
 507   base::WeakPtr<SpdyStream> stream = stream_;
 508   DCHECK(stream);
 509   Reset();
 510   return stream;
 511 }
 512
 513 void SpdyStreamRequest::OnRequestCompleteSuccess(
 514     const base::WeakPtr<SpdyStream>& stream) {
 515   DCHECK(session_);
 516   DCHECK(!stream_);
 517   DCHECK(!callback_.is_null());
 518   CompletionCallback callback = callback_;
 519   Reset();
 520   DCHECK(stream);
 521   stream_ = stream;
 522   callback.Run(OK);
 523 }
 524
 525 void SpdyStreamRequest::OnRequestCompleteFailure(int rv) {
 526   DCHECK(session_);
 527   DCHECK(!stream_);
 528   DCHECK(!callback_.is_null());
 529   CompletionCallback callback = callback_;
 530   Reset();
 531   DCHECK_NE(rv, OK);
 532   callback.Run(rv);
 533 }
 534
 535 void SpdyStreamRequest::Reset() {
 536   type_ = SPDY_BIDIRECTIONAL_STREAM;
 537   session_.reset();
 538   stream_.reset();
 539   url_ = GURL();
 540   priority_ = MINIMUM_PRIORITY;
 541   net_log_ = BoundNetLog();
 542   callback_.Reset();
 543 }
 544
 545 SpdySession::ActiveStreamInfo::ActiveStreamInfo()
 546     : stream(NULL),
 547       waiting_for_syn_reply(false) {}
 548
 549 SpdySession::ActiveStreamInfo::ActiveStreamInfo(SpdyStream* stream)
 550     : stream(stream),
 551       waiting_for_syn_reply(stream->type() != SPDY_PUSH_STREAM) {
 552 }
 553
 554 SpdySession::ActiveStreamInfo::~ActiveStreamInfo() {}
 555
 556 SpdySession::PushedStreamInfo::PushedStreamInfo() : stream_id(0) {}
 557
 558 SpdySession::PushedStreamInfo::PushedStreamInfo(
 559     SpdyStreamId stream_id,
 560     base::TimeTicks creation_time)
 561     : stream_id(stream_id),
 562       creation_time(creation_time) {}
 563
 564 SpdySession::PushedStreamInfo::~PushedStreamInfo() {}
 565
 566 // static
 567 bool SpdySession::CanPool(TransportSecurityState* transport_security_state,
 568                           const SSLInfo& ssl_info,
 569                           const std::string& old_hostname,
 570                           const std::string& new_hostname) {
 571   // Pooling is prohibited if the server cert is not valid for the new domain,
 572   // and for connections on which client certs were sent. It is also prohibited
 573   // when channel ID was sent if the hosts are from different eTLDs+1.
 574   if (IsCertStatusError(ssl_info.cert_status))
 575     return false;
 576
 577   if (ssl_info.client_cert_sent)
 578     return false;
 579
 580   if (ssl_info.channel_id_sent &&
 581       ChannelIDService::GetDomainForHost(new_hostname) !=
 582       ChannelIDService::GetDomainForHost(old_hostname)) {
 583     return false;
 584   }
 585
 586   bool unused = false;
 587   if (!ssl_info.cert->VerifyNameMatch(new_hostname, &unused))
 588     return false;
 589
 590   std::string pinning_failure_log;
 591   if (!transport_security_state->CheckPublicKeyPins(
 592           new_hostname,
 593           ssl_info.is_issued_by_known_root,
 594           ssl_info.public_key_hashes,
 595           &pinning_failure_log)) {
 596     return false;
 597   }
 598
 599   return true;
 600 }
 601
 602 SpdySession::SpdySession(
 603     const SpdySessionKey& spdy_session_key,
 604     const base::WeakPtr<HttpServerProperties>& http_server_properties,
 605     TransportSecurityState* transport_security_state,
 606     bool verify_domain_authentication,
 607     bool enable_sending_initial_data,
 608     bool enable_compression,
 609     bool enable_ping_based_connection_checking,
 610     NextProto default_protocol,
 611     size_t stream_initial_recv_window_size,
 612     size_t initial_max_concurrent_streams,
 613     size_t max_concurrent_streams_limit,
 614     TimeFunc time_func,
 615     const HostPortPair& trusted_spdy_proxy,
 616     NetLog* net_log)
 617     : in_io_loop_(false),
 618       spdy_session_key_(spdy_session_key),
 619       pool_(NULL),
 620       http_server_properties_(http_server_properties),
 621       transport_security_state_(transport_security_state),
 622       read_buffer_(new IOBuffer(kReadBufferSize)),
 623       stream_hi_water_mark_(kFirstStreamId),
 624       last_accepted_push_stream_id_(0),
 625       num_pushed_streams_(0u),
 626       num_active_pushed_streams_(0u),
 627       in_flight_write_frame_type_(DATA),
 628       in_flight_write_frame_size_(0),
 629       is_secure_(false),
 630       certificate_error_code_(OK),
 631       availability_state_(STATE_AVAILABLE),
 632       read_state_(READ_STATE_DO_READ),
 633       write_state_(WRITE_STATE_IDLE),
 634       error_on_close_(OK),
 635       max_concurrent_streams_(initial_max_concurrent_streams == 0
 636                                   ? kInitialMaxConcurrentStreams
 637                                   : initial_max_concurrent_streams),
 638       max_concurrent_streams_limit_(max_concurrent_streams_limit == 0
 639                                         ? kMaxConcurrentStreamLimit
 640                                         : max_concurrent_streams_limit),
 641       max_concurrent_pushed_streams_(kMaxConcurrentPushedStreams),
 642       streams_initiated_count_(0),
 643       streams_pushed_count_(0),
 644       streams_pushed_and_claimed_count_(0),
 645       streams_abandoned_count_(0),
 646       total_bytes_received_(0),
 647       sent_settings_(false),
 648       received_settings_(false),
 649       stalled_streams_(0),
 650       pings_in_flight_(0),
 651       next_ping_id_(1),
 652       last_activity_time_(time_func()),
 653       last_compressed_frame_len_(0),
 654       check_ping_status_pending_(false),
 655       send_connection_header_prefix_(false),
 656       flow_control_state_(FLOW_CONTROL_NONE),
 657       stream_initial_send_window_size_(GetInitialWindowSize(default_protocol)),
 658       stream_initial_recv_window_size_(stream_initial_recv_window_size == 0
 659                                            ? kDefaultInitialRecvWindowSize
 660                                            : stream_initial_recv_window_size),
 661       session_send_window_size_(0),
 662       session_recv_window_size_(0),
 663       session_unacked_recv_window_bytes_(0),
 664       net_log_(BoundNetLog::Make(net_log, NetLog::SOURCE_HTTP2_SESSION)),
 665       verify_domain_authentication_(verify_domain_authentication),
 666       enable_sending_initial_data_(enable_sending_initial_data),
 667       enable_compression_(enable_compression),
 668       enable_ping_based_connection_checking_(
 669           enable_ping_based_connection_checking),
 670       protocol_(default_protocol),
 671       connection_at_risk_of_loss_time_(
 672           base::TimeDelta::FromSeconds(kDefaultConnectionAtRiskOfLossSeconds)),
 673       hung_interval_(base::TimeDelta::FromSeconds(kHungIntervalSeconds)),
 674       trusted_spdy_proxy_(trusted_spdy_proxy),
 675       time_func_(time_func),
 676       weak_factory_(this) {
 677   DCHECK_GE(protocol_, kProtoSPDYMinimumVersion);
 678   DCHECK_LE(protocol_, kProtoSPDYMaximumVersion);
 679   DCHECK(HttpStreamFactory::spdy_enabled());
 680   net_log_.BeginEvent(
 681       NetLog::TYPE_HTTP2_SESSION,
 682       base::Bind(&NetLogSpdySessionCallback, &host_port_proxy_pair()));
 683   next_unclaimed_push_stream_sweep_time_ = time_func_() +
 684       base::TimeDelta::FromSeconds(kMinPushedStreamLifetimeSeconds);
 685   // TODO(mbelshe): consider randomization of the stream_hi_water_mark.
 686 }
 687
 688 SpdySession::~SpdySession() {
 689   CHECK(!in_io_loop_);
 690   DcheckDraining();
 691
 692   // TODO(akalin): Check connection->is_initialized() instead. This
 693   // requires re-working CreateFakeSpdySession(), though.
 694   DCHECK(connection_->socket());
 695   // With SPDY we can't recycle sockets.
 696   connection_->socket()->Disconnect();
 697
 698   RecordHistograms();
 699
 700   net_log_.EndEvent(NetLog::TYPE_HTTP2_SESSION);
 701 }
 702
 703 void SpdySession::InitializeWithSocket(
 704     scoped_ptr<ClientSocketHandle> connection,
 705     SpdySessionPool* pool,
 706     bool is_secure,
 707     int certificate_error_code) {
 708   CHECK(!in_io_loop_);
 709   DCHECK_EQ(availability_state_, STATE_AVAILABLE);
 710   DCHECK_EQ(read_state_, READ_STATE_DO_READ);
 711   DCHECK_EQ(write_state_, WRITE_STATE_IDLE);
 712   DCHECK(!connection_);
 713
 714   DCHECK(certificate_error_code == OK ||
 715          certificate_error_code < ERR_IO_PENDING);
 716   // TODO(akalin): Check connection->is_initialized() instead. This
 717   // requires re-working CreateFakeSpdySession(), though.
 718   DCHECK(connection->socket());
 719
 720   connection_ = connection.Pass();
 721   is_secure_ = is_secure;
 722   certificate_error_code_ = certificate_error_code;
 723
 724   NextProto protocol_negotiated =
 725       connection_->socket()->GetNegotiatedProtocol();
 726   if (protocol_negotiated != kProtoUnknown) {
 727     protocol_ = protocol_negotiated;
 728     stream_initial_send_window_size_ = GetInitialWindowSize(protocol_);
 729   }
 730   DCHECK_GE(protocol_, kProtoSPDYMinimumVersion);
 731   DCHECK_LE(protocol_, kProtoSPDYMaximumVersion);
 732
 733   if ((protocol_ >= kProtoSPDY4MinimumVersion) &&
 734       (protocol_ <= kProtoSPDY4MaximumVersion))
 735     send_connection_header_prefix_ = true;
 736
 737   if (protocol_ >= kProtoSPDY31) {
 738     flow_control_state_ = FLOW_CONTROL_STREAM_AND_SESSION;
 739     session_send_window_size_ = GetInitialWindowSize(protocol_);
 740     session_recv_window_size_ = GetInitialWindowSize(protocol_);
 741   } else if (protocol_ >= kProtoSPDY3) {
 742     flow_control_state_ = FLOW_CONTROL_STREAM;
 743   } else {
 744     flow_control_state_ = FLOW_CONTROL_NONE;
 745   }
 746
 747   buffered_spdy_framer_.reset(
 748       new BufferedSpdyFramer(NextProtoToSpdyMajorVersion(protocol_),
 749                              enable_compression_));
 750   buffered_spdy_framer_->set_visitor(this);
 751   buffered_spdy_framer_->set_debug_visitor(this);
 752   UMA_HISTOGRAM_ENUMERATION(
 753       "Net.SpdyVersion2",
 754       protocol_ - kProtoSPDYHistogramOffset,
 755       kProtoSPDYMaximumVersion - kProtoSPDYMinimumVersion + 1);
 756
 757   net_log_.AddEvent(
 758       NetLog::TYPE_HTTP2_SESSION_INITIALIZED,
 759       base::Bind(&NetLogSpdyInitializedCallback,
 760                  connection_->socket()->NetLog().source(), protocol_));
 761
 762   DCHECK_EQ(availability_state_, STATE_AVAILABLE);
 763   connection_->AddHigherLayeredPool(this);
 764   if (enable_sending_initial_data_)
 765     SendInitialData();
 766   pool_ = pool;
 767
 768   // Bootstrap the read loop.
 769   base::MessageLoop::current()->PostTask(
 770       FROM_HERE,
 771       base::Bind(&SpdySession::PumpReadLoop,
 772                  weak_factory_.GetWeakPtr(), READ_STATE_DO_READ, OK));
 773 }
 774
 775 bool SpdySession::VerifyDomainAuthentication(const std::string& domain) {
 776   if (!verify_domain_authentication_)
 777     return true;
 778
 779   if (availability_state_ == STATE_DRAINING)
 780     return false;
 781
 782   SSLInfo ssl_info;
 783   bool was_npn_negotiated;
 784   NextProto protocol_negotiated = kProtoUnknown;
 785   if (!GetSSLInfo(&ssl_info, &was_npn_negotiated, &protocol_negotiated))
 786     return true;   // This is not a secure session, so all domains are okay.
 787
 788   return CanPool(transport_security_state_, ssl_info,
 789                  host_port_pair().host(), domain);
 790 }
 791
 792 int SpdySession::GetPushStream(
 793     const GURL& url,
 794     base::WeakPtr<SpdyStream>* stream,
 795     const BoundNetLog& stream_net_log) {
 796   CHECK(!in_io_loop_);
 797
 798   stream->reset();
 799
 800   if (availability_state_ == STATE_DRAINING)
 801     return ERR_CONNECTION_CLOSED;
 802
 803   Error err = TryAccessStream(url);
 804   if (err != OK)
 805     return err;
 806
 807   *stream = GetActivePushStream(url);
 808   if (*stream) {
 809     DCHECK_LT(streams_pushed_and_claimed_count_, streams_pushed_count_);
 810     streams_pushed_and_claimed_count_++;
 811   }
 812   return OK;
 813 }
 814
 815 // {,Try}CreateStream() and TryAccessStream() can be called with
 816 // |in_io_loop_| set if a stream is being created in response to
 817 // another being closed due to received data.
 818
 819 Error SpdySession::TryAccessStream(const GURL& url) {
 820   if (is_secure_ && certificate_error_code_ != OK &&
 821       (url.SchemeIs("https") || url.SchemeIs("wss"))) {
 822     RecordProtocolErrorHistogram(
 823         PROTOCOL_ERROR_REQUEST_FOR_SECURE_CONTENT_OVER_INSECURE_SESSION);
 824     DoDrainSession(
 825         static_cast<Error>(certificate_error_code_),
 826         "Tried to get SPDY stream for secure content over an unauthenticated "
 827         "session.");
 828     return ERR_SPDY_PROTOCOL_ERROR;
 829   }
 830   return OK;
 831 }
 832
 833 int SpdySession::TryCreateStream(
 834     const base::WeakPtr<SpdyStreamRequest>& request,
 835     base::WeakPtr<SpdyStream>* stream) {
 836   DCHECK(request);
 837
 838   if (availability_state_ == STATE_GOING_AWAY)
 839     return ERR_FAILED;
 840
 841   if (availability_state_ == STATE_DRAINING)
 842     return ERR_CONNECTION_CLOSED;
 843
 844   Error err = TryAccessStream(request->url());
 845   if (err != OK)
 846     return err;
 847
 848   if (!max_concurrent_streams_ ||
 849       (active_streams_.size() + created_streams_.size() - num_pushed_streams_ <
 850        max_concurrent_streams_)) {
 851     return CreateStream(*request, stream);
 852   }
 853
 854   stalled_streams_++;
 855   net_log().AddEvent(NetLog::TYPE_HTTP2_SESSION_STALLED_MAX_STREAMS);
 856   RequestPriority priority = request->priority();
 857   CHECK_GE(priority, MINIMUM_PRIORITY);
 858   CHECK_LE(priority, MAXIMUM_PRIORITY);
 859   pending_create_stream_queues_[priority].push_back(request);
 860   return ERR_IO_PENDING;
 861 }
 862
 863 int SpdySession::CreateStream(const SpdyStreamRequest& request,
 864                               base::WeakPtr<SpdyStream>* stream) {
 865   DCHECK_GE(request.priority(), MINIMUM_PRIORITY);
 866   DCHECK_LE(request.priority(), MAXIMUM_PRIORITY);
 867
 868   if (availability_state_ == STATE_GOING_AWAY)
 869     return ERR_FAILED;
 870
 871   if (availability_state_ == STATE_DRAINING)
 872     return ERR_CONNECTION_CLOSED;
 873
 874   Error err = TryAccessStream(request.url());
 875   if (err != OK) {
 876     // This should have been caught in TryCreateStream().
 877     NOTREACHED();
 878     return err;
 879   }
 880
 881   DCHECK(connection_->socket());
 882   DCHECK(connection_->socket()->IsConnected());
 883   if (connection_->socket()) {
 884     UMA_HISTOGRAM_BOOLEAN("Net.SpdySession.CreateStreamWithSocketConnected",
 885                           connection_->socket()->IsConnected());
 886     if (!connection_->socket()->IsConnected()) {
 887       DoDrainSession(
 888           ERR_CONNECTION_CLOSED,
 889           "Tried to create SPDY stream for a closed socket connection.");
 890       return ERR_CONNECTION_CLOSED;
 891     }
 892   }
 893
 894   scoped_ptr<SpdyStream> new_stream(
 895       new SpdyStream(request.type(), GetWeakPtr(), request.url(),
 896                      request.priority(),
 897                      stream_initial_send_window_size_,
 898                      stream_initial_recv_window_size_,
 899                      request.net_log()));
 900   *stream = new_stream->GetWeakPtr();
 901   InsertCreatedStream(new_stream.Pass());
 902
 903   UMA_HISTOGRAM_CUSTOM_COUNTS(
 904       "Net.SpdyPriorityCount",
 905       static_cast<int>(request.priority()), 0, 10, 11);
 906
 907   return OK;
 908 }
 909
 910 void SpdySession::CancelStreamRequest(
 911     const base::WeakPtr<SpdyStreamRequest>& request) {
 912   DCHECK(request);
 913   RequestPriority priority = request->priority();
 914   CHECK_GE(priority, MINIMUM_PRIORITY);
 915   CHECK_LE(priority, MAXIMUM_PRIORITY);
 916
 917 #if DCHECK_IS_ON()
 918   // |request| should not be in a queue not matching its priority.
 919   for (int i = MINIMUM_PRIORITY; i <= MAXIMUM_PRIORITY; ++i) {
 920     if (priority == i)
 921       continue;
 922     PendingStreamRequestQueue* queue = &pending_create_stream_queues_[i];
 923     DCHECK(std::find_if(queue->begin(),
 924                         queue->end(),
 925                         RequestEquals(request)) == queue->end());
 926   }
 927 #endif
 928
 929   PendingStreamRequestQueue* queue =
 930       &pending_create_stream_queues_[priority];
 931   // Remove |request| from |queue| while preserving the order of the
 932   // other elements.
 933   PendingStreamRequestQueue::iterator it =
 934       std::find_if(queue->begin(), queue->end(), RequestEquals(request));
 935   // The request may already be removed if there's a
 936   // CompleteStreamRequest() in flight.
 937   if (it != queue->end()) {
 938     it = queue->erase(it);
 939     // |request| should be in the queue at most once, and if it is
 940     // present, should not be pending completion.
 941     DCHECK(std::find_if(it, queue->end(), RequestEquals(request)) ==
 942            queue->end());
 943   }
 944 }
 945
 946 base::WeakPtr<SpdyStreamRequest> SpdySession::GetNextPendingStreamRequest() {
 947   for (int j = MAXIMUM_PRIORITY; j >= MINIMUM_PRIORITY; --j) {
 948     if (pending_create_stream_queues_[j].empty())
 949       continue;
 950
 951     base::WeakPtr<SpdyStreamRequest> pending_request =
 952         pending_create_stream_queues_[j].front();
 953     DCHECK(pending_request);
 954     pending_create_stream_queues_[j].pop_front();
 955     return pending_request;
 956   }
 957   return base::WeakPtr<SpdyStreamRequest>();
 958 }
 959
 960 void SpdySession::ProcessPendingStreamRequests() {
 961   // Like |max_concurrent_streams_|, 0 means infinite for
 962   // |max_requests_to_process|.
 963   size_t max_requests_to_process = 0;
 964   if (max_concurrent_streams_ != 0) {
 965     max_requests_to_process =
 966         max_concurrent_streams_ -
 967         (active_streams_.size() + created_streams_.size());
 968   }
 969   for (size_t i = 0;
 970        max_requests_to_process == 0 || i < max_requests_to_process; ++i) {
 971     base::WeakPtr<SpdyStreamRequest> pending_request =
 972         GetNextPendingStreamRequest();
 973     if (!pending_request)
 974       break;
 975
 976     // Note that this post can race with other stream creations, and it's
 977     // possible that the un-stalled stream will be stalled again if it loses.
 978     // TODO(jgraettinger): Provide stronger ordering guarantees.
 979     base::MessageLoop::current()->PostTask(
 980         FROM_HERE,
 981         base::Bind(&SpdySession::CompleteStreamRequest,
 982                    weak_factory_.GetWeakPtr(),
 983                    pending_request));
 984   }
 985 }
 986
 987 void SpdySession::AddPooledAlias(const SpdySessionKey& alias_key) {
 988   pooled_aliases_.insert(alias_key);
 989 }
 990
 991 SpdyMajorVersion SpdySession::GetProtocolVersion() const {
 992   DCHECK(buffered_spdy_framer_.get());
 993   return buffered_spdy_framer_->protocol_version();
 994 }
 995
 996 bool SpdySession::HasAcceptableTransportSecurity() const {
 997   // If we're not even using TLS, we have no standards to meet.
 998   if (!is_secure_) {
 999     return true;
1000   }
1001
1002   // We don't enforce transport security standards for older SPDY versions.
1003   if (GetProtocolVersion() < SPDY4) {
1004     return true;
1005   }
1006
1007   SSLInfo ssl_info;
1008   CHECK(connection_->socket()->GetSSLInfo(&ssl_info));
1009
1010   // HTTP/2 requires TLS 1.2+
1011   if (SSLConnectionStatusToVersion(ssl_info.connection_status) <
1012       SSL_CONNECTION_VERSION_TLS1_2) {
1013     return false;
1014   }
1015
1016   if (!IsSecureTLSCipherSuite(
1017           SSLConnectionStatusToCipherSuite(ssl_info.connection_status))) {
1018     return false;
1019   }
1020
1021   return true;
1022 }
1023
1024 base::WeakPtr<SpdySession> SpdySession::GetWeakPtr() {
1025   return weak_factory_.GetWeakPtr();
1026 }
1027
1028 bool SpdySession::CloseOneIdleConnection() {
1029   CHECK(!in_io_loop_);
1030   DCHECK(pool_);
1031   if (active_streams_.empty()) {
1032     DoDrainSession(ERR_CONNECTION_CLOSED, "Closing idle connection.");
1033   }
1034   // Return false as the socket wasn't immediately closed.
1035   return false;
1036 }
1037
1038 void SpdySession::EnqueueStreamWrite(
1039     const base::WeakPtr<SpdyStream>& stream,
1040     SpdyFrameType frame_type,
1041     scoped_ptr<SpdyBufferProducer> producer) {
1042   DCHECK(frame_type == HEADERS ||
1043          frame_type == DATA ||
1044          frame_type == CREDENTIAL ||
1045          frame_type == SYN_STREAM);
1046   EnqueueWrite(stream->priority(), frame_type, producer.Pass(), stream);
1047 }
1048
1049 scoped_ptr<SpdyFrame> SpdySession::CreateSynStream(
1050     SpdyStreamId stream_id,
1051     RequestPriority priority,
1052     SpdyControlFlags flags,
1053     const SpdyHeaderBlock& block) {
1054   ActiveStreamMap::const_iterator it = active_streams_.find(stream_id);
1055   CHECK(it != active_streams_.end());
1056   CHECK_EQ(it->second.stream->stream_id(), stream_id);
1057
1058   SendPrefacePingIfNoneInFlight();
1059
1060   DCHECK(buffered_spdy_framer_.get());
1061   SpdyPriority spdy_priority =
1062       ConvertRequestPriorityToSpdyPriority(priority, GetProtocolVersion());
1063
1064   scoped_ptr<SpdyFrame> syn_frame;
1065   // TODO(hkhalil): Avoid copy of |block|.
1066   if (GetProtocolVersion() <= SPDY3) {
1067     SpdySynStreamIR syn_stream(stream_id);
1068     syn_stream.set_associated_to_stream_id(0);
1069     syn_stream.set_priority(spdy_priority);
1070     syn_stream.set_fin((flags & CONTROL_FLAG_FIN) != 0);
1071     syn_stream.set_unidirectional((flags & CONTROL_FLAG_UNIDIRECTIONAL) != 0);
1072     syn_stream.set_name_value_block(block);
1073     syn_frame.reset(buffered_spdy_framer_->SerializeFrame(syn_stream));
1074   } else {
1075     SpdyHeadersIR headers(stream_id);
1076     headers.set_priority(spdy_priority);
1077     headers.set_has_priority(true);
1078     headers.set_fin((flags & CONTROL_FLAG_FIN) != 0);
1079     headers.set_name_value_block(block);
1080     syn_frame.reset(buffered_spdy_framer_->SerializeFrame(headers));
1081   }
1082
1083   streams_initiated_count_++;
1084
1085   if (net_log().IsLogging()) {
1086     const NetLog::EventType type =
1087         (GetProtocolVersion() <= SPDY3)
1088             ? NetLog::TYPE_HTTP2_SESSION_SYN_STREAM
1089             : NetLog::TYPE_HTTP2_SESSION_SEND_HEADERS;
1090     net_log().AddEvent(type,
1091                        base::Bind(&NetLogSpdySynStreamSentCallback, &block,
1092                                   (flags & CONTROL_FLAG_FIN) != 0,
1093                                   (flags & CONTROL_FLAG_UNIDIRECTIONAL) != 0,
1094                                   spdy_priority, stream_id));
1095   }
1096
1097   return syn_frame.Pass();
1098 }
1099
1100 scoped_ptr<SpdyBuffer> SpdySession::CreateDataBuffer(SpdyStreamId stream_id,
1101                                                      IOBuffer* data,
1102                                                      int len,
1103                                                      SpdyDataFlags flags) {
1104   if (availability_state_ == STATE_DRAINING) {
1105     return scoped_ptr<SpdyBuffer>();
1106   }
1107
1108   ActiveStreamMap::const_iterator it = active_streams_.find(stream_id);
1109   CHECK(it != active_streams_.end());
1110   SpdyStream* stream = it->second.stream;
1111   CHECK_EQ(stream->stream_id(), stream_id);
1112
1113   if (len < 0) {
1114     NOTREACHED();
1115     return scoped_ptr<SpdyBuffer>();
1116   }
1117
1118   int effective_len = std::min(len, kMaxSpdyFrameChunkSize);
1119
1120   bool send_stalled_by_stream =
1121       (flow_control_state_ >= FLOW_CONTROL_STREAM) &&
1122       (stream->send_window_size() <= 0);
1123   bool send_stalled_by_session = IsSendStalled();
1124
1125   // NOTE: There's an enum of the same name in histograms.xml.
1126   enum SpdyFrameFlowControlState {
1127     SEND_NOT_STALLED,
1128     SEND_STALLED_BY_STREAM,
1129     SEND_STALLED_BY_SESSION,
1130     SEND_STALLED_BY_STREAM_AND_SESSION,
1131   };
1132
1133   SpdyFrameFlowControlState frame_flow_control_state = SEND_NOT_STALLED;
1134   if (send_stalled_by_stream) {
1135     if (send_stalled_by_session) {
1136       frame_flow_control_state = SEND_STALLED_BY_STREAM_AND_SESSION;
1137     } else {
1138       frame_flow_control_state = SEND_STALLED_BY_STREAM;
1139     }
1140   } else if (send_stalled_by_session) {
1141     frame_flow_control_state = SEND_STALLED_BY_SESSION;
1142   }
1143
1144   if (flow_control_state_ == FLOW_CONTROL_STREAM) {
1145     UMA_HISTOGRAM_ENUMERATION(
1146         "Net.SpdyFrameStreamFlowControlState",
1147         frame_flow_control_state,
1148         SEND_STALLED_BY_STREAM + 1);
1149   } else if (flow_control_state_ == FLOW_CONTROL_STREAM_AND_SESSION) {
1150     UMA_HISTOGRAM_ENUMERATION(
1151         "Net.SpdyFrameStreamAndSessionFlowControlState",
1152         frame_flow_control_state,
1153         SEND_STALLED_BY_STREAM_AND_SESSION + 1);
1154   }
1155
1156   // Obey send window size of the stream if stream flow control is
1157   // enabled.
1158   if (flow_control_state_ >= FLOW_CONTROL_STREAM) {
1159     if (send_stalled_by_stream) {
1160       stream->set_send_stalled_by_flow_control(true);
1161       // Even though we're currently stalled only by the stream, we
1162       // might end up being stalled by the session also.
1163       QueueSendStalledStream(*stream);
1164       net_log().AddEvent(
1165           NetLog::TYPE_HTTP2_SESSION_STREAM_STALLED_BY_STREAM_SEND_WINDOW,
1166           NetLog::IntegerCallback("stream_id", stream_id));
1167       return scoped_ptr<SpdyBuffer>();
1168     }
1169
1170     effective_len = std::min(effective_len, stream->send_window_size());
1171   }
1172
1173   // Obey send window size of the session if session flow control is
1174   // enabled.
1175   if (flow_control_state_ == FLOW_CONTROL_STREAM_AND_SESSION) {
1176     if (send_stalled_by_session) {
1177       stream->set_send_stalled_by_flow_control(true);
1178       QueueSendStalledStream(*stream);
1179       net_log().AddEvent(
1180           NetLog::TYPE_HTTP2_SESSION_STREAM_STALLED_BY_SESSION_SEND_WINDOW,
1181           NetLog::IntegerCallback("stream_id", stream_id));
1182       return scoped_ptr<SpdyBuffer>();
1183     }
1184
1185     effective_len = std::min(effective_len, session_send_window_size_);
1186   }
1187
1188   DCHECK_GE(effective_len, 0);
1189
1190   // Clear FIN flag if only some of the data will be in the data
1191   // frame.
1192   if (effective_len < len)
1193     flags = static_cast<SpdyDataFlags>(flags & ~DATA_FLAG_FIN);
1194
1195   if (net_log().IsLogging()) {
1196     net_log().AddEvent(NetLog::TYPE_HTTP2_SESSION_SEND_DATA,
1197                        base::Bind(&NetLogSpdyDataCallback, stream_id,
1198                                   effective_len, (flags & DATA_FLAG_FIN) != 0));
1199   }
1200
1201   // Send PrefacePing for DATA_FRAMEs with nonzero payload size.
1202   if (effective_len > 0)
1203     SendPrefacePingIfNoneInFlight();
1204
1205   // TODO(mbelshe): reduce memory copies here.
1206   DCHECK(buffered_spdy_framer_.get());
1207   scoped_ptr<SpdyFrame> frame(
1208       buffered_spdy_framer_->CreateDataFrame(
1209           stream_id, data->data(),
1210           static_cast<uint32>(effective_len), flags));
1211
1212   scoped_ptr<SpdyBuffer> data_buffer(new SpdyBuffer(frame.Pass()));
1213
1214   // Send window size is based on payload size, so nothing to do if this is
1215   // just a FIN with no payload.
1216   if (flow_control_state_ == FLOW_CONTROL_STREAM_AND_SESSION &&
1217       effective_len != 0) {
1218     DecreaseSendWindowSize(static_cast<int32>(effective_len));
1219     data_buffer->AddConsumeCallback(
1220         base::Bind(&SpdySession::OnWriteBufferConsumed,
1221                    weak_factory_.GetWeakPtr(),
1222                    static_cast<size_t>(effective_len)));
1223   }
1224
1225   return data_buffer.Pass();
1226 }
1227
1228 void SpdySession::CloseActiveStream(SpdyStreamId stream_id, int status) {
1229   DCHECK_NE(stream_id, 0u);
1230
1231   ActiveStreamMap::iterator it = active_streams_.find(stream_id);
1232   if (it == active_streams_.end()) {
1233     NOTREACHED();
1234     return;
1235   }
1236
1237   CloseActiveStreamIterator(it, status);
1238 }
1239
1240 void SpdySession::CloseCreatedStream(
1241     const base::WeakPtr<SpdyStream>& stream, int status) {
1242   DCHECK_EQ(stream->stream_id(), 0u);
1243
1244   CreatedStreamSet::iterator it = created_streams_.find(stream.get());
1245   if (it == created_streams_.end()) {
1246     NOTREACHED();
1247     return;
1248   }
1249
1250   CloseCreatedStreamIterator(it, status);
1251 }
1252
1253 void SpdySession::ResetStream(SpdyStreamId stream_id,
1254                               SpdyRstStreamStatus status,
1255                               const std::string& description) {
1256   DCHECK_NE(stream_id, 0u);
1257
1258   ActiveStreamMap::iterator it = active_streams_.find(stream_id);
1259   if (it == active_streams_.end()) {
1260     NOTREACHED();
1261     return;
1262   }
1263
1264   ResetStreamIterator(it, status, description);
1265 }
1266
1267 bool SpdySession::IsStreamActive(SpdyStreamId stream_id) const {
1268   return ContainsKey(active_streams_, stream_id);
1269 }
1270
1271 LoadState SpdySession::GetLoadState() const {
1272   // Just report that we're idle since the session could be doing
1273   // many things concurrently.
1274   return LOAD_STATE_IDLE;
1275 }
1276
1277 void SpdySession::CloseActiveStreamIterator(ActiveStreamMap::iterator it,
1278                                             int status) {
1279   // TODO(mbelshe): We should send a RST_STREAM control frame here
1280   //                so that the server can cancel a large send.
1281
1282   scoped_ptr<SpdyStream> owned_stream(it->second.stream);
1283   active_streams_.erase(it);
1284
1285   // TODO(akalin): When SpdyStream was ref-counted (and
1286   // |unclaimed_pushed_streams_| held scoped_refptr<SpdyStream>), this
1287   // was only done when status was not OK. This meant that pushed
1288   // streams can still be claimed after they're closed. This is
1289   // probably something that we still want to support, although server
1290   // push is hardly used. Write tests for this and fix this. (See
1291   // http://crbug.com/261712 .)
1292   if (owned_stream->type() == SPDY_PUSH_STREAM) {
1293     unclaimed_pushed_streams_.erase(owned_stream->url());
1294     num_pushed_streams_--;
1295     if (!owned_stream->IsReservedRemote())
1296       num_active_pushed_streams_--;
1297   }
1298
1299   DeleteStream(owned_stream.Pass(), status);
1300   MaybeFinishGoingAway();
1301
1302   // If there are no active streams and the socket pool is stalled, close the
1303   // session to free up a socket slot.
1304   if (active_streams_.empty() && connection_->IsPoolStalled()) {
1305     DoDrainSession(ERR_CONNECTION_CLOSED, "Closing idle connection.");
1306   }
1307 }
1308
1309 void SpdySession::CloseCreatedStreamIterator(CreatedStreamSet::iterator it,
1310                                              int status) {
1311   scoped_ptr<SpdyStream> owned_stream(*it);
1312   created_streams_.erase(it);
1313   DeleteStream(owned_stream.Pass(), status);
1314 }
1315
1316 void SpdySession::ResetStreamIterator(ActiveStreamMap::iterator it,
1317                                       SpdyRstStreamStatus status,
1318                                       const std::string& description) {
1319   // Send the RST_STREAM frame first as CloseActiveStreamIterator()
1320   // may close us.
1321   SpdyStreamId stream_id = it->first;
1322   RequestPriority priority = it->second.stream->priority();
1323   EnqueueResetStreamFrame(stream_id, priority, status, description);
1324
1325   // Removes any pending writes for the stream except for possibly an
1326   // in-flight one.
1327   CloseActiveStreamIterator(it, ERR_SPDY_PROTOCOL_ERROR);
1328 }
1329
1330 void SpdySession::EnqueueResetStreamFrame(SpdyStreamId stream_id,
1331                                           RequestPriority priority,
1332                                           SpdyRstStreamStatus status,
1333                                           const std::string& description) {
1334   DCHECK_NE(stream_id, 0u);
1335
1336   net_log().AddEvent(
1337       NetLog::TYPE_HTTP2_SESSION_SEND_RST_STREAM,
1338       base::Bind(&NetLogSpdyRstCallback, stream_id, status, &description));
1339
1340   DCHECK(buffered_spdy_framer_.get());
1341   scoped_ptr<SpdyFrame> rst_frame(
1342       buffered_spdy_framer_->CreateRstStream(stream_id, status));
1343
1344   EnqueueSessionWrite(priority, RST_STREAM, rst_frame.Pass());
1345   RecordProtocolErrorHistogram(MapRstStreamStatusToProtocolError(status));
1346 }
1347
1348 void SpdySession::PumpReadLoop(ReadState expected_read_state, int result) {
1349   // TODO(vadimt): Remove ScopedTracker below once crbug.com/418183 is fixed.
1350   tracked_objects::ScopedTracker tracking_profile(
1351       FROM_HERE_WITH_EXPLICIT_FUNCTION(
1352           "418183 DoReadCallback => SpdySession::PumpReadLoop"));
1353
1354   CHECK(!in_io_loop_);
1355   if (availability_state_ == STATE_DRAINING) {
1356     return;
1357   }
1358   ignore_result(DoReadLoop(expected_read_state, result));
1359 }
1360
1361 int SpdySession::DoReadLoop(ReadState expected_read_state, int result) {
1362   CHECK(!in_io_loop_);
1363   CHECK_EQ(read_state_, expected_read_state);
1364
1365   in_io_loop_ = true;
1366
1367   int bytes_read_without_yielding = 0;
1368
1369   // Loop until the session is draining, the read becomes blocked, or
1370   // the read limit is exceeded.
1371   while (true) {
1372     switch (read_state_) {
1373       case READ_STATE_DO_READ:
1374         CHECK_EQ(result, OK);
1375         result = DoRead();
1376         break;
1377       case READ_STATE_DO_READ_COMPLETE:
1378         if (result > 0)
1379           bytes_read_without_yielding += result;
1380         result = DoReadComplete(result);
1381         break;
1382       default:
1383         NOTREACHED() << "read_state_: " << read_state_;
1384         break;
1385     }
1386
1387     if (availability_state_ == STATE_DRAINING)
1388       break;
1389
1390     if (result == ERR_IO_PENDING)
1391       break;
1392
1393     if (bytes_read_without_yielding > kMaxReadBytesWithoutYielding) {
1394       read_state_ = READ_STATE_DO_READ;
1395       base::MessageLoop::current()->PostTask(
1396           FROM_HERE,
1397           base::Bind(&SpdySession::PumpReadLoop,
1398                      weak_factory_.GetWeakPtr(), READ_STATE_DO_READ, OK));
1399       result = ERR_IO_PENDING;
1400       break;
1401     }
1402   }
1403
1404   CHECK(in_io_loop_);
1405   in_io_loop_ = false;
1406
1407   return result;
1408 }
1409
1410 int SpdySession::DoRead() {
1411   CHECK(in_io_loop_);
1412
1413   CHECK(connection_);
1414   CHECK(connection_->socket());
1415   read_state_ = READ_STATE_DO_READ_COMPLETE;
1416   return connection_->socket()->Read(
1417       read_buffer_.get(),
1418       kReadBufferSize,
1419       base::Bind(&SpdySession::PumpReadLoop,
1420                  weak_factory_.GetWeakPtr(), READ_STATE_DO_READ_COMPLETE));
1421 }
1422
1423 int SpdySession::DoReadComplete(int result) {
1424   CHECK(in_io_loop_);
1425
1426   // Parse a frame.  For now this code requires that the frame fit into our
1427   // buffer (kReadBufferSize).
1428   // TODO(mbelshe): support arbitrarily large frames!
1429
1430   if (result == 0) {
1431     UMA_HISTOGRAM_CUSTOM_COUNTS("Net.SpdySession.BytesRead.EOF",
1432                                 total_bytes_received_, 1, 100000000, 50);
1433     DoDrainSession(ERR_CONNECTION_CLOSED, "Connection closed");
1434
1435     return ERR_CONNECTION_CLOSED;
1436   }
1437
1438   if (result < 0) {
1439     DoDrainSession(static_cast<Error>(result), "result is < 0.");
1440     return result;
1441   }
1442   CHECK_LE(result, kReadBufferSize);
1443   total_bytes_received_ += result;
1444
1445   last_activity_time_ = time_func_();
1446
1447   DCHECK(buffered_spdy_framer_.get());
1448   char* data = read_buffer_->data();
1449   while (result > 0) {
1450     uint32 bytes_processed = buffered_spdy_framer_->ProcessInput(data, result);
1451     result -= bytes_processed;
1452     data += bytes_processed;
1453
1454     if (availability_state_ == STATE_DRAINING) {
1455       return ERR_CONNECTION_CLOSED;
1456     }
1457
1458     DCHECK_EQ(buffered_spdy_framer_->error_code(), SpdyFramer::SPDY_NO_ERROR);
1459   }
1460
1461   read_state_ = READ_STATE_DO_READ;
1462   return OK;
1463 }
1464
1465 void SpdySession::PumpWriteLoop(WriteState expected_write_state, int result) {
1466   CHECK(!in_io_loop_);
1467   DCHECK_EQ(write_state_, expected_write_state);
1468
1469   DoWriteLoop(expected_write_state, result);
1470
1471   if (availability_state_ == STATE_DRAINING && !in_flight_write_ &&
1472       write_queue_.IsEmpty()) {
1473     pool_->RemoveUnavailableSession(GetWeakPtr());  // Destroys |this|.
1474     return;
1475   }
1476 }
1477
1478 int SpdySession::DoWriteLoop(WriteState expected_write_state, int result) {
1479   CHECK(!in_io_loop_);
1480   DCHECK_NE(write_state_, WRITE_STATE_IDLE);
1481   DCHECK_EQ(write_state_, expected_write_state);
1482
1483   in_io_loop_ = true;
1484
1485   // Loop until the session is closed or the write becomes blocked.
1486   while (true) {
1487     switch (write_state_) {
1488       case WRITE_STATE_DO_WRITE:
1489         DCHECK_EQ(result, OK);
1490         result = DoWrite();
1491         break;
1492       case WRITE_STATE_DO_WRITE_COMPLETE:
1493         result = DoWriteComplete(result);
1494         break;
1495       case WRITE_STATE_IDLE:
1496       default:
1497         NOTREACHED() << "write_state_: " << write_state_;
1498         break;
1499     }
1500
1501     if (write_state_ == WRITE_STATE_IDLE) {
1502       DCHECK_EQ(result, ERR_IO_PENDING);
1503       break;
1504     }
1505
1506     if (result == ERR_IO_PENDING)
1507       break;
1508   }
1509
1510   CHECK(in_io_loop_);
1511   in_io_loop_ = false;
1512
1513   return result;
1514 }
1515
1516 int SpdySession::DoWrite() {
1517   CHECK(in_io_loop_);
1518
1519   DCHECK(buffered_spdy_framer_);
1520   if (in_flight_write_) {
1521     DCHECK_GT(in_flight_write_->GetRemainingSize(), 0u);
1522   } else {
1523     // Grab the next frame to send.
1524     SpdyFrameType frame_type = DATA;
1525     scoped_ptr<SpdyBufferProducer> producer;
1526     base::WeakPtr<SpdyStream> stream;
1527     if (!write_queue_.Dequeue(&frame_type, &producer, &stream)) {
1528       write_state_ = WRITE_STATE_IDLE;
1529       return ERR_IO_PENDING;
1530     }
1531
1532     if (stream.get())
1533       CHECK(!stream->IsClosed());
1534
1535     // Activate the stream only when sending the SYN_STREAM frame to
1536     // guarantee monotonically-increasing stream IDs.
1537     if (frame_type == SYN_STREAM) {
1538       CHECK(stream.get());
1539       CHECK_EQ(stream->stream_id(), 0u);
1540       scoped_ptr<SpdyStream> owned_stream =
1541           ActivateCreatedStream(stream.get());
1542       InsertActivatedStream(owned_stream.Pass());
1543
1544       if (stream_hi_water_mark_ > kLastStreamId) {
1545         CHECK_EQ(stream->stream_id(), kLastStreamId);
1546         // We've exhausted the stream ID space, and no new streams may be
1547         // created after this one.
1548         MakeUnavailable();
1549         StartGoingAway(kLastStreamId, ERR_ABORTED);
1550       }
1551     }
1552
1553     // TODO(pkasting): Remove ScopedTracker below once crbug.com/457517 is
1554     // fixed.
1555     tracked_objects::ScopedTracker tracking_profile1(
1556         FROM_HERE_WITH_EXPLICIT_FUNCTION("457517 SpdySession::DoWrite1"));
1557     in_flight_write_ = producer->ProduceBuffer();
1558     if (!in_flight_write_) {
1559       NOTREACHED();
1560       return ERR_UNEXPECTED;
1561     }
1562     in_flight_write_frame_type_ = frame_type;
1563     in_flight_write_frame_size_ = in_flight_write_->GetRemainingSize();
1564     DCHECK_GE(in_flight_write_frame_size_,
1565               buffered_spdy_framer_->GetFrameMinimumSize());
1566     in_flight_write_stream_ = stream;
1567   }
1568
1569   write_state_ = WRITE_STATE_DO_WRITE_COMPLETE;
1570
1571   // Explicitly store in a scoped_refptr<IOBuffer> to avoid problems
1572   // with Socket implementations that don't store their IOBuffer
1573   // argument in a scoped_refptr<IOBuffer> (see crbug.com/232345).
1574   // TODO(pkasting): Remove ScopedTracker below once crbug.com/457517 is fixed.
1575   tracked_objects::ScopedTracker tracking_profile2(
1576       FROM_HERE_WITH_EXPLICIT_FUNCTION("457517 SpdySession::DoWrite2"));
1577   scoped_refptr<IOBuffer> write_io_buffer =
1578       in_flight_write_->GetIOBufferForRemainingData();
1579   return connection_->socket()->Write(
1580       write_io_buffer.get(),
1581       in_flight_write_->GetRemainingSize(),
1582       base::Bind(&SpdySession::PumpWriteLoop,
1583                  weak_factory_.GetWeakPtr(), WRITE_STATE_DO_WRITE_COMPLETE));
1584 }
1585
1586 int SpdySession::DoWriteComplete(int result) {
1587   CHECK(in_io_loop_);
1588   DCHECK_NE(result, ERR_IO_PENDING);
1589   DCHECK_GT(in_flight_write_->GetRemainingSize(), 0u);
1590
1591   last_activity_time_ = time_func_();
1592
1593   if (result < 0) {
1594     DCHECK_NE(result, ERR_IO_PENDING);
1595     in_flight_write_.reset();
1596     in_flight_write_frame_type_ = DATA;
1597     in_flight_write_frame_size_ = 0;
1598     in_flight_write_stream_.reset();
1599     write_state_ = WRITE_STATE_DO_WRITE;
1600     DoDrainSession(static_cast<Error>(result), "Write error");
1601     return OK;
1602   }
1603
1604   // It should not be possible to have written more bytes than our
1605   // in_flight_write_.
1606   DCHECK_LE(static_cast<size_t>(result),
1607             in_flight_write_->GetRemainingSize());
1608
1609   if (result > 0) {
1610     in_flight_write_->Consume(static_cast<size_t>(result));
1611
1612     // We only notify the stream when we've fully written the pending frame.
1613     if (in_flight_write_->GetRemainingSize() == 0) {
1614       // It is possible that the stream was cancelled while we were
1615       // writing to the socket.
1616       if (in_flight_write_stream_.get()) {
1617         DCHECK_GT(in_flight_write_frame_size_, 0u);
1618         in_flight_write_stream_->OnFrameWriteComplete(
1619             in_flight_write_frame_type_,
1620             in_flight_write_frame_size_);
1621       }
1622
1623       // Cleanup the write which just completed.
1624       in_flight_write_.reset();
1625       in_flight_write_frame_type_ = DATA;
1626       in_flight_write_frame_size_ = 0;
1627       in_flight_write_stream_.reset();
1628     }
1629   }
1630
1631   write_state_ = WRITE_STATE_DO_WRITE;
1632   return OK;
1633 }
1634
1635 void SpdySession::DcheckGoingAway() const {
1636 #if DCHECK_IS_ON()
1637   DCHECK_GE(availability_state_, STATE_GOING_AWAY);
1638   for (int i = MINIMUM_PRIORITY; i <= MAXIMUM_PRIORITY; ++i) {
1639     DCHECK(pending_create_stream_queues_[i].empty());
1640   }
1641   DCHECK(created_streams_.empty());
1642 #endif
1643 }
1644
1645 void SpdySession::DcheckDraining() const {
1646   DcheckGoingAway();
1647   DCHECK_EQ(availability_state_, STATE_DRAINING);
1648   DCHECK(active_streams_.empty());
1649   DCHECK(unclaimed_pushed_streams_.empty());
1650 }
1651
1652 void SpdySession::StartGoingAway(SpdyStreamId last_good_stream_id,
1653                                  Error status) {
1654   DCHECK_GE(availability_state_, STATE_GOING_AWAY);
1655
1656   // The loops below are carefully written to avoid reentrancy problems.
1657
1658   while (true) {
1659     size_t old_size = GetTotalSize(pending_create_stream_queues_);
1660     base::WeakPtr<SpdyStreamRequest> pending_request =
1661         GetNextPendingStreamRequest();
1662     if (!pending_request)
1663       break;
1664     // No new stream requests should be added while the session is
1665     // going away.
1666     DCHECK_GT(old_size, GetTotalSize(pending_create_stream_queues_));
1667     pending_request->OnRequestCompleteFailure(ERR_ABORTED);
1668   }
1669
1670   while (true) {
1671     size_t old_size = active_streams_.size();
1672     ActiveStreamMap::iterator it =
1673         active_streams_.lower_bound(last_good_stream_id + 1);
1674     if (it == active_streams_.end())
1675       break;
1676     LogAbandonedActiveStream(it, status);
1677     CloseActiveStreamIterator(it, status);
1678     // No new streams should be activated while the session is going
1679     // away.
1680     DCHECK_GT(old_size, active_streams_.size());
1681   }
1682
1683   while (!created_streams_.empty()) {
1684     size_t old_size = created_streams_.size();
1685     CreatedStreamSet::iterator it = created_streams_.begin();
1686     LogAbandonedStream(*it, status);
1687     CloseCreatedStreamIterator(it, status);
1688     // No new streams should be created while the session is going
1689     // away.
1690     DCHECK_GT(old_size, created_streams_.size());
1691   }
1692
1693   write_queue_.RemovePendingWritesForStreamsAfter(last_good_stream_id);
1694
1695   DcheckGoingAway();
1696 }
1697
1698 void SpdySession::MaybeFinishGoingAway() {
1699   if (active_streams_.empty() && availability_state_ == STATE_GOING_AWAY) {
1700     DoDrainSession(OK, "Finished going away");
1701   }
1702 }
1703
1704 void SpdySession::DoDrainSession(Error err, const std::string& description) {
1705   if (availability_state_ == STATE_DRAINING) {
1706     return;
1707   }
1708   MakeUnavailable();
1709
1710   // Mark host_port_pair requiring HTTP/1.1 for subsequent connections.
1711   if (err == ERR_HTTP_1_1_REQUIRED) {
1712     http_server_properties_->SetHTTP11Required(host_port_pair());
1713   }
1714
1715   // If |err| indicates an error occurred, inform the peer that we're closing
1716   // and why. Don't GOAWAY on a graceful or idle close, as that may
1717   // unnecessarily wake the radio. We could technically GOAWAY on network errors
1718   // (we'll probably fail to actually write it, but that's okay), however many
1719   // unit-tests would need to be updated.
1720   if (err != OK &&
1721       err != ERR_ABORTED &&  // Used by SpdySessionPool to close idle sessions.
1722       err != ERR_NETWORK_CHANGED &&  // Used to deprecate sessions on IP change.
1723       err != ERR_SOCKET_NOT_CONNECTED && err != ERR_HTTP_1_1_REQUIRED &&
1724       err != ERR_CONNECTION_CLOSED && err != ERR_CONNECTION_RESET) {
1725     // Enqueue a GOAWAY to inform the peer of why we're closing the connection.
1726     SpdyGoAwayIR goaway_ir(last_accepted_push_stream_id_,
1727                            MapNetErrorToGoAwayStatus(err),
1728                            description);
1729     EnqueueSessionWrite(HIGHEST,
1730                         GOAWAY,
1731                         scoped_ptr<SpdyFrame>(
1732                             buffered_spdy_framer_->SerializeFrame(goaway_ir)));
1733   }
1734
1735   availability_state_ = STATE_DRAINING;
1736   error_on_close_ = err;
1737
1738   net_log_.AddEvent(
1739       NetLog::TYPE_HTTP2_SESSION_CLOSE,
1740       base::Bind(&NetLogSpdySessionCloseCallback, err, &description));
1741
1742   UMA_HISTOGRAM_SPARSE_SLOWLY("Net.SpdySession.ClosedOnError", -err);
1743   UMA_HISTOGRAM_CUSTOM_COUNTS("Net.SpdySession.BytesRead.OtherErrors",
1744                               total_bytes_received_, 1, 100000000, 50);
1745
1746   if (err == OK) {
1747     // We ought to be going away already, as this is a graceful close.
1748     DcheckGoingAway();
1749   } else {
1750     StartGoingAway(0, err);
1751   }
1752   DcheckDraining();
1753   MaybePostWriteLoop();
1754 }
1755
1756 void SpdySession::LogAbandonedStream(SpdyStream* stream, Error status) {
1757   DCHECK(stream);
1758   std::string description = base::StringPrintf(
1759       "ABANDONED (stream_id=%d): ", stream->stream_id()) +
1760       stream->url().spec();
1761   stream->LogStreamError(status, description);
1762   // We don't increment the streams abandoned counter here. If the
1763   // stream isn't active (i.e., it hasn't written anything to the wire
1764   // yet) then it's as if it never existed. If it is active, then
1765   // LogAbandonedActiveStream() will increment the counters.
1766 }
1767
1768 void SpdySession::LogAbandonedActiveStream(ActiveStreamMap::const_iterator it,
1769                                            Error status) {
1770   DCHECK_GT(it->first, 0u);
1771   LogAbandonedStream(it->second.stream, status);
1772   ++streams_abandoned_count_;
1773   if (it->second.stream->type() == SPDY_PUSH_STREAM &&
1774       unclaimed_pushed_streams_.find(it->second.stream->url()) !=
1775       unclaimed_pushed_streams_.end()) {
1776   }
1777 }
1778
1779 SpdyStreamId SpdySession::GetNewStreamId() {
1780   CHECK_LE(stream_hi_water_mark_, kLastStreamId);
1781   SpdyStreamId id = stream_hi_water_mark_;
1782   stream_hi_water_mark_ += 2;
1783   return id;
1784 }
1785
1786 void SpdySession::CloseSessionOnError(Error err,
1787                                       const std::string& description) {
1788   DCHECK_LT(err, ERR_IO_PENDING);
1789   DoDrainSession(err, description);
1790 }
1791
1792 void SpdySession::MakeUnavailable() {
1793   if (availability_state_ == STATE_AVAILABLE) {
1794     availability_state_ = STATE_GOING_AWAY;
1795     pool_->MakeSessionUnavailable(GetWeakPtr());
1796   }
1797 }
1798
1799 base::Value* SpdySession::GetInfoAsValue() const {
1800   base::DictionaryValue* dict = new base::DictionaryValue();
1801
1802   dict->SetInteger("source_id", net_log_.source().id);
1803
1804   dict->SetString("host_port_pair", host_port_pair().ToString());
1805   if (!pooled_aliases_.empty()) {
1806     base::ListValue* alias_list = new base::ListValue();
1807     for (std::set<SpdySessionKey>::const_iterator it =
1808              pooled_aliases_.begin();
1809          it != pooled_aliases_.end(); it++) {
1810       alias_list->Append(new base::StringValue(
1811           it->host_port_pair().ToString()));
1812     }
1813     dict->Set("aliases", alias_list);
1814   }
1815   dict->SetString("proxy", host_port_proxy_pair().second.ToURI());
1816
1817   dict->SetInteger("active_streams", active_streams_.size());
1818
1819   dict->SetInteger("unclaimed_pushed_streams",
1820                    unclaimed_pushed_streams_.size());
1821
1822   dict->SetBoolean("is_secure", is_secure_);
1823
1824   dict->SetString("protocol_negotiated",
1825                   SSLClientSocket::NextProtoToString(
1826                       connection_->socket()->GetNegotiatedProtocol()));
1827
1828   dict->SetInteger("error", error_on_close_);
1829   dict->SetInteger("max_concurrent_streams", max_concurrent_streams_);
1830
1831   dict->SetInteger("streams_initiated_count", streams_initiated_count_);
1832   dict->SetInteger("streams_pushed_count", streams_pushed_count_);
1833   dict->SetInteger("streams_pushed_and_claimed_count",
1834       streams_pushed_and_claimed_count_);
1835   dict->SetInteger("streams_abandoned_count", streams_abandoned_count_);
1836   DCHECK(buffered_spdy_framer_.get());
1837   dict->SetInteger("frames_received", buffered_spdy_framer_->frames_received());
1838
1839   dict->SetBoolean("sent_settings", sent_settings_);
1840   dict->SetBoolean("received_settings", received_settings_);
1841
1842   dict->SetInteger("send_window_size", session_send_window_size_);
1843   dict->SetInteger("recv_window_size", session_recv_window_size_);
1844   dict->SetInteger("unacked_recv_window_bytes",
1845                    session_unacked_recv_window_bytes_);
1846   return dict;
1847 }
1848
1849 bool SpdySession::IsReused() const {
1850   return buffered_spdy_framer_->frames_received() > 0 ||
1851       connection_->reuse_type() == ClientSocketHandle::UNUSED_IDLE;
1852 }
1853
1854 bool SpdySession::GetLoadTimingInfo(SpdyStreamId stream_id,
1855                                     LoadTimingInfo* load_timing_info) const {
1856   return connection_->GetLoadTimingInfo(stream_id != kFirstStreamId,
1857                                         load_timing_info);
1858 }
1859
1860 int SpdySession::GetPeerAddress(IPEndPoint* address) const {
1861   int rv = ERR_SOCKET_NOT_CONNECTED;
1862   if (connection_->socket()) {
1863     rv = connection_->socket()->GetPeerAddress(address);
1864   }
1865
1866   UMA_HISTOGRAM_BOOLEAN("Net.SpdySessionSocketNotConnectedGetPeerAddress",
1867                         rv == ERR_SOCKET_NOT_CONNECTED);
1868
1869   return rv;
1870 }
1871
1872 int SpdySession::GetLocalAddress(IPEndPoint* address) const {
1873   int rv = ERR_SOCKET_NOT_CONNECTED;
1874   if (connection_->socket()) {
1875     rv = connection_->socket()->GetLocalAddress(address);
1876   }
1877
1878   UMA_HISTOGRAM_BOOLEAN("Net.SpdySessionSocketNotConnectedGetLocalAddress",
1879                         rv == ERR_SOCKET_NOT_CONNECTED);
1880
1881   return rv;
1882 }
1883
1884 void SpdySession::EnqueueSessionWrite(RequestPriority priority,
1885                                       SpdyFrameType frame_type,
1886                                       scoped_ptr<SpdyFrame> frame) {
1887   DCHECK(frame_type == RST_STREAM || frame_type == SETTINGS ||
1888          frame_type == WINDOW_UPDATE || frame_type == PING ||
1889          frame_type == GOAWAY);
1890   EnqueueWrite(
1891       priority, frame_type,
1892       scoped_ptr<SpdyBufferProducer>(
1893           new SimpleBufferProducer(
1894               scoped_ptr<SpdyBuffer>(new SpdyBuffer(frame.Pass())))),
1895       base::WeakPtr<SpdyStream>());
1896 }
1897
1898 void SpdySession::EnqueueWrite(RequestPriority priority,
1899                                SpdyFrameType frame_type,
1900                                scoped_ptr<SpdyBufferProducer> producer,
1901                                const base::WeakPtr<SpdyStream>& stream) {
1902   if (availability_state_ == STATE_DRAINING)
1903     return;
1904
1905   write_queue_.Enqueue(priority, frame_type, producer.Pass(), stream);
1906   MaybePostWriteLoop();
1907 }
1908
1909 void SpdySession::MaybePostWriteLoop() {
1910   if (write_state_ == WRITE_STATE_IDLE) {
1911     CHECK(!in_flight_write_);
1912     write_state_ = WRITE_STATE_DO_WRITE;
1913     base::MessageLoop::current()->PostTask(
1914         FROM_HERE,
1915         base::Bind(&SpdySession::PumpWriteLoop,
1916                    weak_factory_.GetWeakPtr(), WRITE_STATE_DO_WRITE, OK));
1917   }
1918 }
1919
1920 void SpdySession::InsertCreatedStream(scoped_ptr<SpdyStream> stream) {
1921   CHECK_EQ(stream->stream_id(), 0u);
1922   CHECK(created_streams_.find(stream.get()) == created_streams_.end());
1923   created_streams_.insert(stream.release());
1924 }
1925
1926 scoped_ptr<SpdyStream> SpdySession::ActivateCreatedStream(SpdyStream* stream) {
1927   CHECK_EQ(stream->stream_id(), 0u);
1928   CHECK(created_streams_.find(stream) != created_streams_.end());
1929   stream->set_stream_id(GetNewStreamId());
1930   scoped_ptr<SpdyStream> owned_stream(stream);
1931   created_streams_.erase(stream);
1932   return owned_stream.Pass();
1933 }
1934
1935 void SpdySession::InsertActivatedStream(scoped_ptr<SpdyStream> stream) {
1936   SpdyStreamId stream_id = stream->stream_id();
1937   CHECK_NE(stream_id, 0u);
1938   std::pair<ActiveStreamMap::iterator, bool> result =
1939       active_streams_.insert(
1940           std::make_pair(stream_id, ActiveStreamInfo(stream.get())));
1941   CHECK(result.second);
1942   ignore_result(stream.release());
1943 }
1944
1945 void SpdySession::DeleteStream(scoped_ptr<SpdyStream> stream, int status) {
1946   if (in_flight_write_stream_.get() == stream.get()) {
1947     // If we're deleting the stream for the in-flight write, we still
1948     // need to let the write complete, so we clear
1949     // |in_flight_write_stream_| and let the write finish on its own
1950     // without notifying |in_flight_write_stream_|.
1951     in_flight_write_stream_.reset();
1952   }
1953
1954   write_queue_.RemovePendingWritesForStream(stream->GetWeakPtr());
1955   stream->OnClose(status);
1956
1957   if (availability_state_ == STATE_AVAILABLE) {
1958     ProcessPendingStreamRequests();
1959   }
1960 }
1961
1962 base::WeakPtr<SpdyStream> SpdySession::GetActivePushStream(const GURL& url) {
1963   PushedStreamMap::iterator unclaimed_it = unclaimed_pushed_streams_.find(url);
1964   if (unclaimed_it == unclaimed_pushed_streams_.end())
1965     return base::WeakPtr<SpdyStream>();
1966
1967   SpdyStreamId stream_id = unclaimed_it->second.stream_id;
1968   unclaimed_pushed_streams_.erase(unclaimed_it);
1969
1970   ActiveStreamMap::iterator active_it = active_streams_.find(stream_id);
1971   if (active_it == active_streams_.end()) {
1972     NOTREACHED();
1973     return base::WeakPtr<SpdyStream>();
1974   }
1975
1976   net_log_.AddEvent(NetLog::TYPE_HTTP2_STREAM_ADOPTED_PUSH_STREAM,
1977                     base::Bind(&NetLogSpdyAdoptedPushStreamCallback,
1978                                active_it->second.stream->stream_id(), &url));
1979   return active_it->second.stream->GetWeakPtr();
1980 }
1981
1982 bool SpdySession::GetSSLInfo(SSLInfo* ssl_info,
1983                              bool* was_npn_negotiated,
1984                              NextProto* protocol_negotiated) {
1985   *was_npn_negotiated = connection_->socket()->WasNpnNegotiated();
1986   *protocol_negotiated = connection_->socket()->GetNegotiatedProtocol();
1987   return connection_->socket()->GetSSLInfo(ssl_info);
1988 }
1989
1990 bool SpdySession::GetSSLCertRequestInfo(
1991     SSLCertRequestInfo* cert_request_info) {
1992   if (!is_secure_)
1993     return false;
1994   GetSSLClientSocket()->GetSSLCertRequestInfo(cert_request_info);
1995   return true;
1996 }
1997
1998 void SpdySession::OnError(SpdyFramer::SpdyError error_code) {
1999   CHECK(in_io_loop_);
2000
2001   RecordProtocolErrorHistogram(MapFramerErrorToProtocolError(error_code));
2002   std::string description =
2003       base::StringPrintf("Framer error: %d (%s).",
2004                          error_code,
2005                          SpdyFramer::ErrorCodeToString(error_code));
2006   DoDrainSession(MapFramerErrorToNetError(error_code), description);
2007 }
2008
2009 void SpdySession::OnStreamError(SpdyStreamId stream_id,
2010                                 const std::string& description) {
2011   CHECK(in_io_loop_);
2012
2013   ActiveStreamMap::iterator it = active_streams_.find(stream_id);
2014   if (it == active_streams_.end()) {
2015     // We still want to send a frame to reset the stream even if we
2016     // don't know anything about it.
2017     EnqueueResetStreamFrame(
2018         stream_id, IDLE, RST_STREAM_PROTOCOL_ERROR, description);
2019     return;
2020   }
2021
2022   ResetStreamIterator(it, RST_STREAM_PROTOCOL_ERROR, description);
2023 }
2024
2025 void SpdySession::OnDataFrameHeader(SpdyStreamId stream_id,
2026                                     size_t length,
2027                                     bool fin) {
2028   CHECK(in_io_loop_);
2029
2030   ActiveStreamMap::iterator it = active_streams_.find(stream_id);
2031
2032   // By the time data comes in, the stream may already be inactive.
2033   if (it == active_streams_.end())
2034     return;
2035
2036   SpdyStream* stream = it->second.stream;
2037   CHECK_EQ(stream->stream_id(), stream_id);
2038
2039   DCHECK(buffered_spdy_framer_);
2040   size_t header_len = buffered_spdy_framer_->GetDataFrameMinimumSize();
2041   stream->IncrementRawReceivedBytes(header_len);
2042 }
2043
2044 void SpdySession::OnStreamFrameData(SpdyStreamId stream_id,
2045                                     const char* data,
2046                                     size_t len,
2047                                     bool fin) {
2048   CHECK(in_io_loop_);
2049
2050   if (data == NULL && len != 0) {
2051     // This is notification of consumed data padding.
2052     // TODO(jgraettinger): Properly flow padding into WINDOW_UPDATE frames.
2053     // See crbug.com/353012.
2054     return;
2055   }
2056
2057   DCHECK_LT(len, 1u << 24);
2058   if (net_log().IsLogging()) {
2059     net_log().AddEvent(
2060         NetLog::TYPE_HTTP2_SESSION_RECV_DATA,
2061         base::Bind(&NetLogSpdyDataCallback, stream_id, len, fin));
2062   }
2063
2064   // Build the buffer as early as possible so that we go through the
2065   // session flow control checks and update
2066   // |unacked_recv_window_bytes_| properly even when the stream is
2067   // inactive (since the other side has still reduced its session send
2068   // window).
2069   scoped_ptr<SpdyBuffer> buffer;
2070   if (data) {
2071     DCHECK_GT(len, 0u);
2072     CHECK_LE(len, static_cast<size_t>(kReadBufferSize));
2073     buffer.reset(new SpdyBuffer(data, len));
2074
2075     if (flow_control_state_ == FLOW_CONTROL_STREAM_AND_SESSION) {
2076       DecreaseRecvWindowSize(static_cast<int32>(len));
2077       buffer->AddConsumeCallback(
2078           base::Bind(&SpdySession::OnReadBufferConsumed,
2079                      weak_factory_.GetWeakPtr()));
2080     }
2081   } else {
2082     DCHECK_EQ(len, 0u);
2083   }
2084
2085   ActiveStreamMap::iterator it = active_streams_.find(stream_id);
2086
2087   // By the time data comes in, the stream may already be inactive.
2088   if (it == active_streams_.end())
2089     return;
2090
2091   SpdyStream* stream = it->second.stream;
2092   CHECK_EQ(stream->stream_id(), stream_id);
2093
2094   stream->IncrementRawReceivedBytes(len);
2095
2096   if (it->second.waiting_for_syn_reply) {
2097     const std::string& error = "Data received before SYN_REPLY.";
2098     stream->LogStreamError(ERR_SPDY_PROTOCOL_ERROR, error);
2099     ResetStreamIterator(it, RST_STREAM_PROTOCOL_ERROR, error);
2100     return;
2101   }
2102
2103   stream->OnDataReceived(buffer.Pass());
2104 }
2105
2106 void SpdySession::OnSettings(bool clear_persisted) {
2107   CHECK(in_io_loop_);
2108
2109   if (clear_persisted)
2110     http_server_properties_->ClearSpdySettings(host_port_pair());
2111
2112   if (net_log_.IsLogging()) {
2113     net_log_.AddEvent(NetLog::TYPE_HTTP2_SESSION_RECV_SETTINGS,
2114                       base::Bind(&NetLogSpdySettingsCallback, host_port_pair(),
2115                                  clear_persisted));
2116   }
2117
2118   if (GetProtocolVersion() >= SPDY4) {
2119     // Send an acknowledgment of the setting.
2120     SpdySettingsIR settings_ir;
2121     settings_ir.set_is_ack(true);
2122     EnqueueSessionWrite(
2123         HIGHEST,
2124         SETTINGS,
2125         scoped_ptr<SpdyFrame>(
2126             buffered_spdy_framer_->SerializeFrame(settings_ir)));
2127   }
2128 }
2129
2130 void SpdySession::OnSetting(SpdySettingsIds id,
2131                             uint8 flags,
2132                             uint32 value) {
2133   CHECK(in_io_loop_);
2134
2135   HandleSetting(id, value);
2136   http_server_properties_->SetSpdySetting(
2137       host_port_pair(),
2138       id,
2139       static_cast<SpdySettingsFlags>(flags),
2140       value);
2141   received_settings_ = true;
2142
2143   // Log the setting.
2144   const SpdyMajorVersion protocol_version = GetProtocolVersion();
2145   net_log_.AddEvent(NetLog::TYPE_HTTP2_SESSION_RECV_SETTING,
2146                     base::Bind(&NetLogSpdySettingCallback, id, protocol_version,
2147                                static_cast<SpdySettingsFlags>(flags), value));
2148 }
2149
2150 void SpdySession::OnSendCompressedFrame(
2151     SpdyStreamId stream_id,
2152     SpdyFrameType type,
2153     size_t payload_len,
2154     size_t frame_len) {
2155   if (type != SYN_STREAM && type != HEADERS)
2156     return;
2157
2158   DCHECK(buffered_spdy_framer_.get());
2159   size_t compressed_len =
2160       frame_len - buffered_spdy_framer_->GetSynStreamMinimumSize();
2161
2162   if (payload_len) {
2163     // Make sure we avoid early decimal truncation.
2164     int compression_pct = 100 - (100 * compressed_len) / payload_len;
2165     UMA_HISTOGRAM_PERCENTAGE("Net.SpdySynStreamCompressionPercentage",
2166                              compression_pct);
2167   }
2168 }
2169
2170 void SpdySession::OnReceiveCompressedFrame(
2171     SpdyStreamId stream_id,
2172     SpdyFrameType type,
2173     size_t frame_len) {
2174   last_compressed_frame_len_ = frame_len;
2175 }
2176
2177 int SpdySession::OnInitialResponseHeadersReceived(
2178     const SpdyHeaderBlock& response_headers,
2179     base::Time response_time,
2180     base::TimeTicks recv_first_byte_time,
2181     SpdyStream* stream) {
2182   CHECK(in_io_loop_);
2183   SpdyStreamId stream_id = stream->stream_id();
2184
2185   if (stream->type() == SPDY_PUSH_STREAM) {
2186     DCHECK(stream->IsReservedRemote());
2187     if (max_concurrent_pushed_streams_ &&
2188         num_active_pushed_streams_ >= max_concurrent_pushed_streams_) {
2189       ResetStream(stream_id,
2190                   RST_STREAM_REFUSED_STREAM,
2191                   "Stream concurrency limit reached.");
2192       return STATUS_CODE_REFUSED_STREAM;
2193     }
2194   }
2195
2196   if (stream->type() == SPDY_PUSH_STREAM) {
2197     // Will be balanced in DeleteStream.
2198     num_active_pushed_streams_++;
2199   }
2200
2201   // May invalidate |stream|.
2202   int rv = stream->OnInitialResponseHeadersReceived(
2203       response_headers, response_time, recv_first_byte_time);
2204   if (rv < 0) {
2205     DCHECK_NE(rv, ERR_IO_PENDING);
2206     DCHECK(active_streams_.find(stream_id) == active_streams_.end());
2207   }
2208
2209   return rv;
2210 }
2211
2212 void SpdySession::OnSynStream(SpdyStreamId stream_id,
2213                               SpdyStreamId associated_stream_id,
2214                               SpdyPriority priority,
2215                               bool fin,
2216                               bool unidirectional,
2217                               const SpdyHeaderBlock& headers) {
2218   CHECK(in_io_loop_);
2219
2220   DCHECK_LE(GetProtocolVersion(), SPDY3);
2221
2222   base::Time response_time = base::Time::Now();
2223   base::TimeTicks recv_first_byte_time = time_func_();
2224
2225   if (net_log_.IsLogging()) {
2226     net_log_.AddEvent(
2227         NetLog::TYPE_HTTP2_SESSION_PUSHED_SYN_STREAM,
2228         base::Bind(&NetLogSpdySynStreamReceivedCallback, &headers, fin,
2229                    unidirectional, priority, stream_id, associated_stream_id));
2230   }
2231
2232   // Split headers to simulate push promise and response.
2233   SpdyHeaderBlock request_headers;
2234   SpdyHeaderBlock response_headers;
2235   SplitPushedHeadersToRequestAndResponse(
2236       headers, GetProtocolVersion(), &request_headers, &response_headers);
2237
2238   if (!TryCreatePushStream(
2239           stream_id, associated_stream_id, priority, request_headers))
2240     return;
2241
2242   ActiveStreamMap::iterator active_it = active_streams_.find(stream_id);
2243   if (active_it == active_streams_.end()) {
2244     NOTREACHED();
2245     return;
2246   }
2247
2248   OnInitialResponseHeadersReceived(response_headers, response_time,
2249                                    recv_first_byte_time,
2250                                    active_it->second.stream);
2251 }
2252
2253 void SpdySession::DeleteExpiredPushedStreams() {
2254   if (unclaimed_pushed_streams_.empty())
2255     return;
2256
2257   // Check that adequate time has elapsed since the last sweep.
2258   if (time_func_() < next_unclaimed_push_stream_sweep_time_)
2259     return;
2260
2261   // Gather old streams to delete.
2262   base::TimeTicks minimum_freshness = time_func_() -
2263       base::TimeDelta::FromSeconds(kMinPushedStreamLifetimeSeconds);
2264   std::vector<SpdyStreamId> streams_to_close;
2265   for (PushedStreamMap::iterator it = unclaimed_pushed_streams_.begin();
2266        it != unclaimed_pushed_streams_.end(); ++it) {
2267     if (minimum_freshness > it->second.creation_time)
2268       streams_to_close.push_back(it->second.stream_id);
2269   }
2270
2271   for (std::vector<SpdyStreamId>::const_iterator to_close_it =
2272            streams_to_close.begin();
2273        to_close_it != streams_to_close.end(); ++to_close_it) {
2274     ActiveStreamMap::iterator active_it = active_streams_.find(*to_close_it);
2275     if (active_it == active_streams_.end())
2276       continue;
2277
2278     LogAbandonedActiveStream(active_it, ERR_INVALID_SPDY_STREAM);
2279     // CloseActiveStreamIterator() will remove the stream from
2280     // |unclaimed_pushed_streams_|.
2281     ResetStreamIterator(
2282         active_it, RST_STREAM_REFUSED_STREAM, "Stream not claimed.");
2283   }
2284
2285   next_unclaimed_push_stream_sweep_time_ = time_func_() +
2286       base::TimeDelta::FromSeconds(kMinPushedStreamLifetimeSeconds);
2287 }
2288
2289 void SpdySession::OnSynReply(SpdyStreamId stream_id,
2290                              bool fin,
2291                              const SpdyHeaderBlock& headers) {
2292   CHECK(in_io_loop_);
2293
2294   base::Time response_time = base::Time::Now();
2295   base::TimeTicks recv_first_byte_time = time_func_();
2296
2297   if (net_log().IsLogging()) {
2298     net_log().AddEvent(NetLog::TYPE_HTTP2_SESSION_SYN_REPLY,
2299                        base::Bind(&NetLogSpdySynReplyOrHeadersReceivedCallback,
2300                                   &headers, fin, stream_id));
2301   }
2302
2303   ActiveStreamMap::iterator it = active_streams_.find(stream_id);
2304   if (it == active_streams_.end()) {
2305     // NOTE:  it may just be that the stream was cancelled.
2306     return;
2307   }
2308
2309   SpdyStream* stream = it->second.stream;
2310   CHECK_EQ(stream->stream_id(), stream_id);
2311
2312   stream->IncrementRawReceivedBytes(last_compressed_frame_len_);
2313   last_compressed_frame_len_ = 0;
2314
2315   if (GetProtocolVersion() >= SPDY4) {
2316     const std::string& error =
2317         "SPDY4 wasn't expecting SYN_REPLY.";
2318     stream->LogStreamError(ERR_SPDY_PROTOCOL_ERROR, error);
2319     ResetStreamIterator(it, RST_STREAM_PROTOCOL_ERROR, error);
2320     return;
2321   }
2322   if (!it->second.waiting_for_syn_reply) {
2323     const std::string& error =
2324         "Received duplicate SYN_REPLY for stream.";
2325     stream->LogStreamError(ERR_SPDY_PROTOCOL_ERROR, error);
2326     ResetStreamIterator(it, RST_STREAM_PROTOCOL_ERROR, error);
2327     return;
2328   }
2329   it->second.waiting_for_syn_reply = false;
2330
2331   ignore_result(OnInitialResponseHeadersReceived(
2332       headers, response_time, recv_first_byte_time, stream));
2333 }
2334
2335 void SpdySession::OnHeaders(SpdyStreamId stream_id,
2336                             bool has_priority,
2337                             SpdyPriority priority,
2338                             bool fin,
2339                             const SpdyHeaderBlock& headers) {
2340   CHECK(in_io_loop_);
2341
2342   if (net_log().IsLogging()) {
2343     net_log().AddEvent(NetLog::TYPE_HTTP2_SESSION_RECV_HEADERS,
2344                        base::Bind(&NetLogSpdySynReplyOrHeadersReceivedCallback,
2345                                   &headers, fin, stream_id));
2346   }
2347
2348   ActiveStreamMap::iterator it = active_streams_.find(stream_id);
2349   if (it == active_streams_.end()) {
2350     // NOTE:  it may just be that the stream was cancelled.
2351     LOG(WARNING) << "Received HEADERS for invalid stream " << stream_id;
2352     return;
2353   }
2354
2355   SpdyStream* stream = it->second.stream;
2356   CHECK_EQ(stream->stream_id(), stream_id);
2357
2358   stream->IncrementRawReceivedBytes(last_compressed_frame_len_);
2359   last_compressed_frame_len_ = 0;
2360
2361   base::Time response_time = base::Time::Now();
2362   base::TimeTicks recv_first_byte_time = time_func_();
2363
2364   if (it->second.waiting_for_syn_reply) {
2365     if (GetProtocolVersion() < SPDY4) {
2366       const std::string& error =
2367           "Was expecting SYN_REPLY, not HEADERS.";
2368       stream->LogStreamError(ERR_SPDY_PROTOCOL_ERROR, error);
2369       ResetStreamIterator(it, RST_STREAM_PROTOCOL_ERROR, error);
2370       return;
2371     }
2372
2373     it->second.waiting_for_syn_reply = false;
2374     ignore_result(OnInitialResponseHeadersReceived(
2375         headers, response_time, recv_first_byte_time, stream));
2376   } else if (it->second.stream->IsReservedRemote()) {
2377     ignore_result(OnInitialResponseHeadersReceived(
2378         headers, response_time, recv_first_byte_time, stream));
2379   } else {
2380     int rv = stream->OnAdditionalResponseHeadersReceived(headers);
2381     if (rv < 0) {
2382       DCHECK_NE(rv, ERR_IO_PENDING);
2383       DCHECK(active_streams_.find(stream_id) == active_streams_.end());
2384     }
2385   }
2386 }
2387
2388 bool SpdySession::OnUnknownFrame(SpdyStreamId stream_id, int frame_type) {
2389   // Validate stream id.
2390   // Was the frame sent on a stream id that has not been used in this session?
2391   if (stream_id % 2 == 1 && stream_id > stream_hi_water_mark_)
2392     return false;
2393
2394   if (stream_id % 2 == 0 && stream_id > last_accepted_push_stream_id_)
2395     return false;
2396
2397   return true;
2398 }
2399
2400 void SpdySession::OnRstStream(SpdyStreamId stream_id,
2401                               SpdyRstStreamStatus status) {
2402   CHECK(in_io_loop_);
2403
2404   std::string description;
2405   net_log().AddEvent(
2406       NetLog::TYPE_HTTP2_SESSION_RST_STREAM,
2407       base::Bind(&NetLogSpdyRstCallback, stream_id, status, &description));
2408
2409   ActiveStreamMap::iterator it = active_streams_.find(stream_id);
2410   if (it == active_streams_.end()) {
2411     // NOTE:  it may just be that the stream was cancelled.
2412     LOG(WARNING) << "Received RST for invalid stream" << stream_id;
2413     return;
2414   }
2415
2416   CHECK_EQ(it->second.stream->stream_id(), stream_id);
2417
2418   if (status == 0) {
2419     it->second.stream->OnDataReceived(scoped_ptr<SpdyBuffer>());
2420   } else if (status == RST_STREAM_REFUSED_STREAM) {
2421     CloseActiveStreamIterator(it, ERR_SPDY_SERVER_REFUSED_STREAM);
2422   } else if (status == RST_STREAM_HTTP_1_1_REQUIRED) {
2423     // TODO(bnc): Record histogram with number of open streams capped at 50.
2424     it->second.stream->LogStreamError(
2425         ERR_HTTP_1_1_REQUIRED,
2426         base::StringPrintf(
2427             "SPDY session closed because of stream with status: %d", status));
2428     DoDrainSession(ERR_HTTP_1_1_REQUIRED, "HTTP_1_1_REQUIRED for stream.");
2429   } else {
2430     RecordProtocolErrorHistogram(
2431         PROTOCOL_ERROR_RST_STREAM_FOR_NON_ACTIVE_STREAM);
2432     it->second.stream->LogStreamError(
2433         ERR_SPDY_PROTOCOL_ERROR,
2434         base::StringPrintf("SPDY stream closed with status: %d", status));
2435     // TODO(mbelshe): Map from Spdy-protocol errors to something sensical.
2436     //                For now, it doesn't matter much - it is a protocol error.
2437     CloseActiveStreamIterator(it, ERR_SPDY_PROTOCOL_ERROR);
2438   }
2439 }
2440
2441 void SpdySession::OnGoAway(SpdyStreamId last_accepted_stream_id,
2442                            SpdyGoAwayStatus status) {
2443   CHECK(in_io_loop_);
2444
2445   // TODO(jgraettinger): UMA histogram on |status|.
2446
2447   net_log_.AddEvent(NetLog::TYPE_HTTP2_SESSION_GOAWAY,
2448                     base::Bind(&NetLogSpdyGoAwayCallback,
2449                                last_accepted_stream_id, active_streams_.size(),
2450                                unclaimed_pushed_streams_.size(), status));
2451   MakeUnavailable();
2452   if (status == GOAWAY_HTTP_1_1_REQUIRED) {
2453     // TODO(bnc): Record histogram with number of open streams capped at 50.
2454     DoDrainSession(ERR_HTTP_1_1_REQUIRED, "HTTP_1_1_REQUIRED for stream.");
2455   } else {
2456     StartGoingAway(last_accepted_stream_id, ERR_ABORTED);
2457   }
2458   // This is to handle the case when we already don't have any active
2459   // streams (i.e., StartGoingAway() did nothing). Otherwise, we have
2460   // active streams and so the last one being closed will finish the
2461   // going away process (see DeleteStream()).
2462   MaybeFinishGoingAway();
2463 }
2464
2465 void SpdySession::OnPing(SpdyPingId unique_id, bool is_ack) {
2466   CHECK(in_io_loop_);
2467
2468   net_log_.AddEvent(
2469       NetLog::TYPE_HTTP2_SESSION_PING,
2470       base::Bind(&NetLogSpdyPingCallback, unique_id, is_ack, "received"));
2471
2472   // Send response to a PING from server.
2473   if ((protocol_ >= kProtoSPDY4MinimumVersion && !is_ack) ||
2474       (protocol_ < kProtoSPDY4MinimumVersion && unique_id % 2 == 0)) {
2475     WritePingFrame(unique_id, true);
2476     return;
2477   }
2478
2479   --pings_in_flight_;
2480   if (pings_in_flight_ < 0) {
2481     RecordProtocolErrorHistogram(PROTOCOL_ERROR_UNEXPECTED_PING);
2482     DoDrainSession(ERR_SPDY_PROTOCOL_ERROR, "pings_in_flight_ is < 0.");
2483     pings_in_flight_ = 0;
2484     return;
2485   }
2486
2487   if (pings_in_flight_ > 0)
2488     return;
2489
2490   // We will record RTT in histogram when there are no more client sent
2491   // pings_in_flight_.
2492   RecordPingRTTHistogram(time_func_() - last_ping_sent_time_);
2493 }
2494
2495 void SpdySession::OnWindowUpdate(SpdyStreamId stream_id,
2496                                  uint32 delta_window_size) {
2497   CHECK(in_io_loop_);
2498
2499   DCHECK_LE(delta_window_size, static_cast<uint32>(kint32max));
2500   net_log_.AddEvent(NetLog::TYPE_HTTP2_SESSION_RECEIVED_WINDOW_UPDATE_FRAME,
2501                     base::Bind(&NetLogSpdyWindowUpdateFrameCallback, stream_id,
2502                                delta_window_size));
2503
2504   if (stream_id == kSessionFlowControlStreamId) {
2505     // WINDOW_UPDATE for the session.
2506     if (flow_control_state_ < FLOW_CONTROL_STREAM_AND_SESSION) {
2507       LOG(WARNING) << "Received WINDOW_UPDATE for session when "
2508                    << "session flow control is not turned on";
2509       // TODO(akalin): Record an error and close the session.
2510       return;
2511     }
2512
2513     if (delta_window_size < 1u) {
2514       RecordProtocolErrorHistogram(PROTOCOL_ERROR_INVALID_WINDOW_UPDATE_SIZE);
2515       DoDrainSession(
2516           ERR_SPDY_PROTOCOL_ERROR,
2517           "Received WINDOW_UPDATE with an invalid delta_window_size " +
2518               base::UintToString(delta_window_size));
2519       return;
2520     }
2521
2522     IncreaseSendWindowSize(static_cast<int32>(delta_window_size));
2523   } else {
2524     // WINDOW_UPDATE for a stream.
2525     if (flow_control_state_ < FLOW_CONTROL_STREAM) {
2526       // TODO(akalin): Record an error and close the session.
2527       LOG(WARNING) << "Received WINDOW_UPDATE for stream " << stream_id
2528                    << " when flow control is not turned on";
2529       return;
2530     }
2531
2532     ActiveStreamMap::iterator it = active_streams_.find(stream_id);
2533
2534     if (it == active_streams_.end()) {
2535       // NOTE:  it may just be that the stream was cancelled.
2536       LOG(WARNING) << "Received WINDOW_UPDATE for invalid stream " << stream_id;
2537       return;
2538     }
2539
2540     SpdyStream* stream = it->second.stream;
2541     CHECK_EQ(stream->stream_id(), stream_id);
2542
2543     if (delta_window_size < 1u) {
2544       ResetStreamIterator(it,
2545                           RST_STREAM_FLOW_CONTROL_ERROR,
2546                           base::StringPrintf(
2547                               "Received WINDOW_UPDATE with an invalid "
2548                               "delta_window_size %ud", delta_window_size));
2549       return;
2550     }
2551
2552     CHECK_EQ(it->second.stream->stream_id(), stream_id);
2553     it->second.stream->IncreaseSendWindowSize(
2554         static_cast<int32>(delta_window_size));
2555   }
2556 }
2557
2558 bool SpdySession::TryCreatePushStream(SpdyStreamId stream_id,
2559                                       SpdyStreamId associated_stream_id,
2560                                       SpdyPriority priority,
2561                                       const SpdyHeaderBlock& headers) {
2562   // Server-initiated streams should have even sequence numbers.
2563   if ((stream_id & 0x1) != 0) {
2564     LOG(WARNING) << "Received invalid push stream id " << stream_id;
2565     if (GetProtocolVersion() > SPDY2)
2566       CloseSessionOnError(ERR_SPDY_PROTOCOL_ERROR, "Odd push stream id.");
2567     return false;
2568   }
2569
2570   if (GetProtocolVersion() > SPDY2) {
2571     if (stream_id <= last_accepted_push_stream_id_) {
2572       LOG(WARNING) << "Received push stream id lesser or equal to the last "
2573                    << "accepted before " << stream_id;
2574       CloseSessionOnError(
2575           ERR_SPDY_PROTOCOL_ERROR,
2576           "New push stream id must be greater than the last accepted.");
2577       return false;
2578     }
2579   }
2580
2581   if (IsStreamActive(stream_id)) {
2582     // For SPDY3 and higher we should not get here, we'll start going away
2583     // earlier on |last_seen_push_stream_id_| check.
2584     CHECK_GT(SPDY3, GetProtocolVersion());
2585     LOG(WARNING) << "Received push for active stream " << stream_id;
2586     return false;
2587   }
2588
2589   last_accepted_push_stream_id_ = stream_id;
2590
2591   RequestPriority request_priority =
2592       ConvertSpdyPriorityToRequestPriority(priority, GetProtocolVersion());
2593
2594   if (availability_state_ == STATE_GOING_AWAY) {
2595     // TODO(akalin): This behavior isn't in the SPDY spec, although it
2596     // probably should be.
2597     EnqueueResetStreamFrame(stream_id,
2598                             request_priority,
2599                             RST_STREAM_REFUSED_STREAM,
2600                             "push stream request received when going away");
2601     return false;
2602   }
2603
2604   if (associated_stream_id == 0) {
2605     // In SPDY4 0 stream id in PUSH_PROMISE frame leads to framer error and
2606     // session going away. We should never get here.
2607     CHECK_GT(SPDY4, GetProtocolVersion());
2608     std::string description = base::StringPrintf(
2609         "Received invalid associated stream id %d for pushed stream %d",
2610         associated_stream_id,
2611         stream_id);
2612     EnqueueResetStreamFrame(
2613         stream_id, request_priority, RST_STREAM_REFUSED_STREAM, description);
2614     return false;
2615   }
2616
2617   streams_pushed_count_++;
2618
2619   // TODO(mbelshe): DCHECK that this is a GET method?
2620
2621   // Verify that the response had a URL for us.
2622   GURL gurl = GetUrlFromHeaderBlock(headers, GetProtocolVersion(), true);
2623   if (!gurl.is_valid()) {
2624     EnqueueResetStreamFrame(stream_id,
2625                             request_priority,
2626                             RST_STREAM_PROTOCOL_ERROR,
2627                             "Pushed stream url was invalid: " + gurl.spec());
2628     return false;
2629   }
2630
2631   // Verify we have a valid stream association.
2632   ActiveStreamMap::iterator associated_it =
2633       active_streams_.find(associated_stream_id);
2634   if (associated_it == active_streams_.end()) {
2635     EnqueueResetStreamFrame(
2636         stream_id,
2637         request_priority,
2638         RST_STREAM_INVALID_STREAM,
2639         base::StringPrintf("Received push for inactive associated stream %d",
2640                            associated_stream_id));
2641     return false;
2642   }
2643
2644   // Check that the pushed stream advertises the same origin as its associated
2645   // stream. Bypass this check if and only if this session is with a SPDY proxy
2646   // that is trusted explicitly via the --trusted-spdy-proxy switch.
2647   if (trusted_spdy_proxy_.Equals(host_port_pair())) {
2648     // Disallow pushing of HTTPS content.
2649     if (gurl.SchemeIs("https")) {
2650       EnqueueResetStreamFrame(
2651           stream_id,
2652           request_priority,
2653           RST_STREAM_REFUSED_STREAM,
2654           base::StringPrintf("Rejected push of Cross Origin HTTPS content %d",
2655                              associated_stream_id));
2656     }
2657   } else {
2658     GURL associated_url(associated_it->second.stream->GetUrlFromHeaders());
2659     if (associated_url.GetOrigin() != gurl.GetOrigin()) {
2660       EnqueueResetStreamFrame(
2661           stream_id,
2662           request_priority,
2663           RST_STREAM_REFUSED_STREAM,
2664           base::StringPrintf("Rejected Cross Origin Push Stream %d",
2665                              associated_stream_id));
2666       return false;
2667     }
2668   }
2669
2670   // There should not be an existing pushed stream with the same path.
2671   PushedStreamMap::iterator pushed_it =
2672       unclaimed_pushed_streams_.lower_bound(gurl);
2673   if (pushed_it != unclaimed_pushed_streams_.end() &&
2674       pushed_it->first == gurl) {
2675     EnqueueResetStreamFrame(
2676         stream_id,
2677         request_priority,
2678         RST_STREAM_PROTOCOL_ERROR,
2679         "Received duplicate pushed stream with url: " + gurl.spec());
2680     return false;
2681   }
2682
2683   scoped_ptr<SpdyStream> stream(new SpdyStream(SPDY_PUSH_STREAM,
2684                                                GetWeakPtr(),
2685                                                gurl,
2686                                                request_priority,
2687                                                stream_initial_send_window_size_,
2688                                                stream_initial_recv_window_size_,
2689                                                net_log_));
2690   stream->set_stream_id(stream_id);
2691
2692   // In spdy4/http2 PUSH_PROMISE arrives on associated stream.
2693   if (associated_it != active_streams_.end() && GetProtocolVersion() >= SPDY4) {
2694     associated_it->second.stream->IncrementRawReceivedBytes(
2695         last_compressed_frame_len_);
2696   } else {
2697     stream->IncrementRawReceivedBytes(last_compressed_frame_len_);
2698   }
2699
2700   last_compressed_frame_len_ = 0;
2701
2702   PushedStreamMap::iterator inserted_pushed_it =
2703       unclaimed_pushed_streams_.insert(
2704           pushed_it,
2705           std::make_pair(gurl, PushedStreamInfo(stream_id, time_func_())));
2706   DCHECK(inserted_pushed_it != pushed_it);
2707   DeleteExpiredPushedStreams();
2708
2709   InsertActivatedStream(stream.Pass());
2710
2711   ActiveStreamMap::iterator active_it = active_streams_.find(stream_id);
2712   if (active_it == active_streams_.end()) {
2713     NOTREACHED();
2714     return false;
2715   }
2716
2717   active_it->second.stream->OnPushPromiseHeadersReceived(headers);
2718   DCHECK(active_it->second.stream->IsReservedRemote());
2719   num_pushed_streams_++;
2720   return true;
2721 }
2722
2723 void SpdySession::OnPushPromise(SpdyStreamId stream_id,
2724                                 SpdyStreamId promised_stream_id,
2725                                 const SpdyHeaderBlock& headers) {
2726   CHECK(in_io_loop_);
2727
2728   if (net_log_.IsLogging()) {
2729     net_log_.AddEvent(NetLog::TYPE_HTTP2_SESSION_RECV_PUSH_PROMISE,
2730                       base::Bind(&NetLogSpdyPushPromiseReceivedCallback,
2731                                  &headers, stream_id, promised_stream_id));
2732   }
2733
2734   // Any priority will do.
2735   // TODO(baranovich): pass parent stream id priority?
2736   if (!TryCreatePushStream(promised_stream_id, stream_id, 0, headers))
2737     return;
2738 }
2739
2740 void SpdySession::SendStreamWindowUpdate(SpdyStreamId stream_id,
2741                                          uint32 delta_window_size) {
2742   CHECK_GE(flow_control_state_, FLOW_CONTROL_STREAM);
2743   ActiveStreamMap::const_iterator it = active_streams_.find(stream_id);
2744   CHECK(it != active_streams_.end());
2745   CHECK_EQ(it->second.stream->stream_id(), stream_id);
2746   SendWindowUpdateFrame(
2747       stream_id, delta_window_size, it->second.stream->priority());
2748 }
2749
2750 void SpdySession::SendInitialData() {
2751   DCHECK(enable_sending_initial_data_);
2752
2753   if (send_connection_header_prefix_) {
2754     DCHECK_GE(protocol_, kProtoSPDY4MinimumVersion);
2755     DCHECK_LE(protocol_, kProtoSPDY4MaximumVersion);
2756     scoped_ptr<SpdyFrame> connection_header_prefix_frame(
2757         new SpdyFrame(const_cast<char*>(kHttp2ConnectionHeaderPrefix),
2758                       kHttp2ConnectionHeaderPrefixSize,
2759                       false /* take_ownership */));
2760     // Count the prefix as part of the subsequent SETTINGS frame.
2761     EnqueueSessionWrite(HIGHEST, SETTINGS,
2762                         connection_header_prefix_frame.Pass());
2763   }
2764
2765   // First, notify the server about the settings they should use when
2766   // communicating with us.
2767   SettingsMap settings_map;
2768   // Create a new settings frame notifying the server of our
2769   // max concurrent streams and initial window size.
2770   settings_map[SETTINGS_MAX_CONCURRENT_STREAMS] =
2771       SettingsFlagsAndValue(SETTINGS_FLAG_NONE, kMaxConcurrentPushedStreams);
2772   if (flow_control_state_ >= FLOW_CONTROL_STREAM &&
2773       stream_initial_recv_window_size_ != GetInitialWindowSize(protocol_)) {
2774     settings_map[SETTINGS_INITIAL_WINDOW_SIZE] =
2775         SettingsFlagsAndValue(SETTINGS_FLAG_NONE,
2776                               stream_initial_recv_window_size_);
2777   }
2778   SendSettings(settings_map);
2779
2780   // Next, notify the server about our initial recv window size.
2781   if (flow_control_state_ == FLOW_CONTROL_STREAM_AND_SESSION) {
2782     // Bump up the receive window size to the real initial value. This
2783     // has to go here since the WINDOW_UPDATE frame sent by
2784     // IncreaseRecvWindowSize() call uses |buffered_spdy_framer_|.
2785     DCHECK_GT(kDefaultInitialRecvWindowSize, session_recv_window_size_);
2786     // This condition implies that |kDefaultInitialRecvWindowSize| -
2787     // |session_recv_window_size_| doesn't overflow.
2788     DCHECK_GT(session_recv_window_size_, 0);
2789     IncreaseRecvWindowSize(
2790         kDefaultInitialRecvWindowSize - session_recv_window_size_);
2791   }
2792
2793   if (protocol_ <= kProtoSPDY31) {
2794     // Finally, notify the server about the settings they have
2795     // previously told us to use when communicating with them (after
2796     // applying them).
2797     const SettingsMap& server_settings_map =
2798         http_server_properties_->GetSpdySettings(host_port_pair());
2799     if (server_settings_map.empty())
2800       return;
2801
2802     SettingsMap::const_iterator it =
2803         server_settings_map.find(SETTINGS_CURRENT_CWND);
2804     uint32 cwnd = (it != server_settings_map.end()) ? it->second.second : 0;
2805     UMA_HISTOGRAM_CUSTOM_COUNTS("Net.SpdySettingsCwndSent", cwnd, 1, 200, 100);
2806
2807     for (SettingsMap::const_iterator it = server_settings_map.begin();
2808          it != server_settings_map.end(); ++it) {
2809       const SpdySettingsIds new_id = it->first;
2810       const uint32 new_val = it->second.second;
2811       HandleSetting(new_id, new_val);
2812     }
2813
2814     SendSettings(server_settings_map);
2815   }
2816 }
2817
2818
2819 void SpdySession::SendSettings(const SettingsMap& settings) {
2820   const SpdyMajorVersion protocol_version = GetProtocolVersion();
2821   net_log_.AddEvent(
2822       NetLog::TYPE_HTTP2_SESSION_SEND_SETTINGS,
2823       base::Bind(&NetLogSpdySendSettingsCallback, &settings, protocol_version));
2824   // Create the SETTINGS frame and send it.
2825   DCHECK(buffered_spdy_framer_.get());
2826   scoped_ptr<SpdyFrame> settings_frame(
2827       buffered_spdy_framer_->CreateSettings(settings));
2828   sent_settings_ = true;
2829   EnqueueSessionWrite(HIGHEST, SETTINGS, settings_frame.Pass());
2830 }
2831
2832 void SpdySession::HandleSetting(uint32 id, uint32 value) {
2833   switch (id) {
2834     case SETTINGS_MAX_CONCURRENT_STREAMS:
2835       max_concurrent_streams_ = std::min(static_cast<size_t>(value),
2836                                          kMaxConcurrentStreamLimit);
2837       ProcessPendingStreamRequests();
2838       break;
2839     case SETTINGS_INITIAL_WINDOW_SIZE: {
2840       if (flow_control_state_ < FLOW_CONTROL_STREAM) {
2841         net_log().AddEvent(
2842             NetLog::TYPE_HTTP2_SESSION_INITIAL_WINDOW_SIZE_NO_FLOW_CONTROL);
2843         return;
2844       }
2845
2846       if (value > static_cast<uint32>(kint32max)) {
2847         net_log().AddEvent(
2848             NetLog::TYPE_HTTP2_SESSION_INITIAL_WINDOW_SIZE_OUT_OF_RANGE,
2849             NetLog::IntegerCallback("initial_window_size", value));
2850         return;
2851       }
2852
2853       // SETTINGS_INITIAL_WINDOW_SIZE updates initial_send_window_size_ only.
2854       int32 delta_window_size =
2855           static_cast<int32>(value) - stream_initial_send_window_size_;
2856       stream_initial_send_window_size_ = static_cast<int32>(value);
2857       UpdateStreamsSendWindowSize(delta_window_size);
2858       net_log().AddEvent(
2859           NetLog::TYPE_HTTP2_SESSION_UPDATE_STREAMS_SEND_WINDOW_SIZE,
2860           NetLog::IntegerCallback("delta_window_size", delta_window_size));
2861       break;
2862     }
2863   }
2864 }
2865
2866 void SpdySession::UpdateStreamsSendWindowSize(int32 delta_window_size) {
2867   DCHECK_GE(flow_control_state_, FLOW_CONTROL_STREAM);
2868   for (ActiveStreamMap::iterator it = active_streams_.begin();
2869        it != active_streams_.end(); ++it) {
2870     it->second.stream->AdjustSendWindowSize(delta_window_size);
2871   }
2872
2873   for (CreatedStreamSet::const_iterator it = created_streams_.begin();
2874        it != created_streams_.end(); it++) {
2875     (*it)->AdjustSendWindowSize(delta_window_size);
2876   }
2877 }
2878
2879 void SpdySession::SendPrefacePingIfNoneInFlight() {
2880   if (pings_in_flight_ || !enable_ping_based_connection_checking_)
2881     return;
2882
2883   base::TimeTicks now = time_func_();
2884   // If there is no activity in the session, then send a preface-PING.
2885   if ((now - last_activity_time_) > connection_at_risk_of_loss_time_)
2886     SendPrefacePing();
2887 }
2888
2889 void SpdySession::SendPrefacePing() {
2890   WritePingFrame(next_ping_id_, false);
2891 }
2892
2893 void SpdySession::SendWindowUpdateFrame(SpdyStreamId stream_id,
2894                                         uint32 delta_window_size,
2895                                         RequestPriority priority) {
2896   CHECK_GE(flow_control_state_, FLOW_CONTROL_STREAM);
2897   ActiveStreamMap::const_iterator it = active_streams_.find(stream_id);
2898   if (it != active_streams_.end()) {
2899     CHECK_EQ(it->second.stream->stream_id(), stream_id);
2900   } else {
2901     CHECK_EQ(flow_control_state_, FLOW_CONTROL_STREAM_AND_SESSION);
2902     CHECK_EQ(stream_id, kSessionFlowControlStreamId);
2903   }
2904
2905   net_log_.AddEvent(NetLog::TYPE_HTTP2_SESSION_SENT_WINDOW_UPDATE_FRAME,
2906                     base::Bind(&NetLogSpdyWindowUpdateFrameCallback, stream_id,
2907                                delta_window_size));
2908
2909   DCHECK(buffered_spdy_framer_.get());
2910   scoped_ptr<SpdyFrame> window_update_frame(
2911       buffered_spdy_framer_->CreateWindowUpdate(stream_id, delta_window_size));
2912   EnqueueSessionWrite(priority, WINDOW_UPDATE, window_update_frame.Pass());
2913 }
2914
2915 void SpdySession::WritePingFrame(SpdyPingId unique_id, bool is_ack) {
2916   DCHECK(buffered_spdy_framer_.get());
2917   scoped_ptr<SpdyFrame> ping_frame(
2918       buffered_spdy_framer_->CreatePingFrame(unique_id, is_ack));
2919   EnqueueSessionWrite(HIGHEST, PING, ping_frame.Pass());
2920
2921   if (net_log().IsLogging()) {
2922     net_log().AddEvent(
2923         NetLog::TYPE_HTTP2_SESSION_PING,
2924         base::Bind(&NetLogSpdyPingCallback, unique_id, is_ack, "sent"));
2925   }
2926   if (!is_ack) {
2927     next_ping_id_ += 2;
2928     ++pings_in_flight_;
2929     PlanToCheckPingStatus();
2930     last_ping_sent_time_ = time_func_();
2931   }
2932 }
2933
2934 void SpdySession::PlanToCheckPingStatus() {
2935   if (check_ping_status_pending_)
2936     return;
2937
2938   check_ping_status_pending_ = true;
2939   base::MessageLoop::current()->PostDelayedTask(
2940       FROM_HERE,
2941       base::Bind(&SpdySession::CheckPingStatus, weak_factory_.GetWeakPtr(),
2942                  time_func_()), hung_interval_);
2943 }
2944
2945 void SpdySession::CheckPingStatus(base::TimeTicks last_check_time) {
2946   CHECK(!in_io_loop_);
2947
2948   // Check if we got a response back for all PINGs we had sent.
2949   if (pings_in_flight_ == 0) {
2950     check_ping_status_pending_ = false;
2951     return;
2952   }
2953
2954   DCHECK(check_ping_status_pending_);
2955
2956   base::TimeTicks now = time_func_();
2957   base::TimeDelta delay = hung_interval_ - (now - last_activity_time_);
2958
2959   if (delay.InMilliseconds() < 0 || last_activity_time_ < last_check_time) {
2960     // Track all failed PING messages in a separate bucket.
2961     RecordPingRTTHistogram(base::TimeDelta::Max());
2962     DoDrainSession(ERR_SPDY_PING_FAILED, "Failed ping.");
2963     return;
2964   }
2965
2966   // Check the status of connection after a delay.
2967   base::MessageLoop::current()->PostDelayedTask(
2968       FROM_HERE,
2969       base::Bind(&SpdySession::CheckPingStatus, weak_factory_.GetWeakPtr(),
2970                  now),
2971       delay);
2972 }
2973
2974 void SpdySession::RecordPingRTTHistogram(base::TimeDelta duration) {
2975   UMA_HISTOGRAM_TIMES("Net.SpdyPing.RTT", duration);
2976 }
2977
2978 void SpdySession::RecordProtocolErrorHistogram(
2979     SpdyProtocolErrorDetails details) {
2980   UMA_HISTOGRAM_ENUMERATION("Net.SpdySessionErrorDetails2", details,
2981                             NUM_SPDY_PROTOCOL_ERROR_DETAILS);
2982   if (EndsWith(host_port_pair().host(), "google.com", false)) {
2983     UMA_HISTOGRAM_ENUMERATION("Net.SpdySessionErrorDetails_Google2", details,
2984                               NUM_SPDY_PROTOCOL_ERROR_DETAILS);
2985   }
2986 }
2987
2988 void SpdySession::RecordHistograms() {
2989   UMA_HISTOGRAM_CUSTOM_COUNTS("Net.SpdyStreamsPerSession",
2990                               streams_initiated_count_,
2991                               0, 300, 50);
2992   UMA_HISTOGRAM_CUSTOM_COUNTS("Net.SpdyStreamsPushedPerSession",
2993                               streams_pushed_count_,
2994                               0, 300, 50);
2995   UMA_HISTOGRAM_CUSTOM_COUNTS("Net.SpdyStreamsPushedAndClaimedPerSession",
2996                               streams_pushed_and_claimed_count_,
2997                               0, 300, 50);
2998   UMA_HISTOGRAM_CUSTOM_COUNTS("Net.SpdyStreamsAbandonedPerSession",
2999                               streams_abandoned_count_,
3000                               0, 300, 50);
3001   UMA_HISTOGRAM_ENUMERATION("Net.SpdySettingsSent",
3002                             sent_settings_ ? 1 : 0, 2);
3003   UMA_HISTOGRAM_ENUMERATION("Net.SpdySettingsReceived",
3004                             received_settings_ ? 1 : 0, 2);
3005   UMA_HISTOGRAM_CUSTOM_COUNTS("Net.SpdyStreamStallsPerSession",
3006                               stalled_streams_,
3007                               0, 300, 50);
3008   UMA_HISTOGRAM_ENUMERATION("Net.SpdySessionsWithStalls",
3009                             stalled_streams_ > 0 ? 1 : 0, 2);
3010
3011   if (received_settings_) {
3012     // Enumerate the saved settings, and set histograms for it.
3013     const SettingsMap& settings_map =
3014         http_server_properties_->GetSpdySettings(host_port_pair());
3015
3016     SettingsMap::const_iterator it;
3017     for (it = settings_map.begin(); it != settings_map.end(); ++it) {
3018       const SpdySettingsIds id = it->first;
3019       const uint32 val = it->second.second;
3020       switch (id) {
3021         case SETTINGS_CURRENT_CWND:
3022           // Record several different histograms to see if cwnd converges
3023           // for larger volumes of data being sent.
3024           UMA_HISTOGRAM_CUSTOM_COUNTS("Net.SpdySettingsCwnd",
3025                                       val, 1, 200, 100);
3026           if (total_bytes_received_ > 10 * 1024) {
3027             UMA_HISTOGRAM_CUSTOM_COUNTS("Net.SpdySettingsCwnd10K",
3028                                         val, 1, 200, 100);
3029             if (total_bytes_received_ > 25 * 1024) {
3030               UMA_HISTOGRAM_CUSTOM_COUNTS("Net.SpdySettingsCwnd25K",
3031                                           val, 1, 200, 100);
3032               if (total_bytes_received_ > 50 * 1024) {
3033                 UMA_HISTOGRAM_CUSTOM_COUNTS("Net.SpdySettingsCwnd50K",
3034                                             val, 1, 200, 100);
3035                 if (total_bytes_received_ > 100 * 1024) {
3036                   UMA_HISTOGRAM_CUSTOM_COUNTS("Net.SpdySettingsCwnd100K",
3037                                               val, 1, 200, 100);
3038                 }
3039               }
3040             }
3041           }
3042           break;
3043         case SETTINGS_ROUND_TRIP_TIME:
3044           UMA_HISTOGRAM_CUSTOM_COUNTS("Net.SpdySettingsRTT",
3045                                       val, 1, 1200, 100);
3046           break;
3047         case SETTINGS_DOWNLOAD_RETRANS_RATE:
3048           UMA_HISTOGRAM_CUSTOM_COUNTS("Net.SpdySettingsRetransRate",
3049                                       val, 1, 100, 50);
3050           break;
3051         default:
3052           break;
3053       }
3054     }
3055   }
3056 }
3057
3058 void SpdySession::CompleteStreamRequest(
3059     const base::WeakPtr<SpdyStreamRequest>& pending_request) {
3060   // Abort if the request has already been cancelled.
3061   if (!pending_request)
3062     return;
3063
3064   base::WeakPtr<SpdyStream> stream;
3065   int rv = TryCreateStream(pending_request, &stream);
3066
3067   if (rv == OK) {
3068     DCHECK(stream);
3069     pending_request->OnRequestCompleteSuccess(stream);
3070     return;
3071   }
3072   DCHECK(!stream);
3073
3074   if (rv != ERR_IO_PENDING) {
3075     pending_request->OnRequestCompleteFailure(rv);
3076   }
3077 }
3078
3079 SSLClientSocket* SpdySession::GetSSLClientSocket() const {
3080   if (!is_secure_)
3081     return NULL;
3082   SSLClientSocket* ssl_socket =
3083       reinterpret_cast<SSLClientSocket*>(connection_->socket());
3084   DCHECK(ssl_socket);
3085   return ssl_socket;
3086 }
3087
3088 void SpdySession::OnWriteBufferConsumed(
3089     size_t frame_payload_size,
3090     size_t consume_size,
3091     SpdyBuffer::ConsumeSource consume_source) {
3092   // We can be called with |in_io_loop_| set if a write SpdyBuffer is
3093   // deleted (e.g., a stream is closed due to incoming data).
3094
3095   DCHECK_EQ(flow_control_state_, FLOW_CONTROL_STREAM_AND_SESSION);
3096
3097   if (consume_source == SpdyBuffer::DISCARD) {
3098     // If we're discarding a frame or part of it, increase the send
3099     // window by the number of discarded bytes. (Although if we're
3100     // discarding part of a frame, it's probably because of a write
3101     // error and we'll be tearing down the session soon.)
3102     size_t remaining_payload_bytes = std::min(consume_size, frame_payload_size);
3103     DCHECK_GT(remaining_payload_bytes, 0u);
3104     IncreaseSendWindowSize(static_cast<int32>(remaining_payload_bytes));
3105   }
3106   // For consumed bytes, the send window is increased when we receive
3107   // a WINDOW_UPDATE frame.
3108 }
3109
3110 void SpdySession::IncreaseSendWindowSize(int32 delta_window_size) {
3111   // We can be called with |in_io_loop_| set if a SpdyBuffer is
3112   // deleted (e.g., a stream is closed due to incoming data).
3113
3114   DCHECK_EQ(flow_control_state_, FLOW_CONTROL_STREAM_AND_SESSION);
3115   DCHECK_GE(delta_window_size, 1);
3116
3117   // Check for overflow.
3118   int32 max_delta_window_size = kint32max - session_send_window_size_;
3119   if (delta_window_size > max_delta_window_size) {
3120     RecordProtocolErrorHistogram(PROTOCOL_ERROR_INVALID_WINDOW_UPDATE_SIZE);
3121     DoDrainSession(
3122         ERR_SPDY_PROTOCOL_ERROR,
3123         "Received WINDOW_UPDATE [delta: " +
3124             base::IntToString(delta_window_size) +
3125             "] for session overflows session_send_window_size_ [current: " +
3126             base::IntToString(session_send_window_size_) + "]");
3127     return;
3128   }
3129
3130   session_send_window_size_ += delta_window_size;
3131
3132   net_log_.AddEvent(NetLog::TYPE_HTTP2_SESSION_UPDATE_SEND_WINDOW,
3133                     base::Bind(&NetLogSpdySessionWindowUpdateCallback,
3134                                delta_window_size, session_send_window_size_));
3135
3136   DCHECK(!IsSendStalled());
3137   ResumeSendStalledStreams();
3138 }
3139
3140 void SpdySession::DecreaseSendWindowSize(int32 delta_window_size) {
3141   DCHECK_EQ(flow_control_state_, FLOW_CONTROL_STREAM_AND_SESSION);
3142
3143   // We only call this method when sending a frame. Therefore,
3144   // |delta_window_size| should be within the valid frame size range.
3145   DCHECK_GE(delta_window_size, 1);
3146   DCHECK_LE(delta_window_size, kMaxSpdyFrameChunkSize);
3147
3148   // |send_window_size_| should have been at least |delta_window_size| for
3149   // this call to happen.
3150   DCHECK_GE(session_send_window_size_, delta_window_size);
3151
3152   session_send_window_size_ -= delta_window_size;
3153
3154   net_log_.AddEvent(NetLog::TYPE_HTTP2_SESSION_UPDATE_SEND_WINDOW,
3155                     base::Bind(&NetLogSpdySessionWindowUpdateCallback,
3156                                -delta_window_size, session_send_window_size_));
3157 }
3158
3159 void SpdySession::OnReadBufferConsumed(
3160     size_t consume_size,
3161     SpdyBuffer::ConsumeSource consume_source) {
3162   // We can be called with |in_io_loop_| set if a read SpdyBuffer is
3163   // deleted (e.g., discarded by a SpdyReadQueue).
3164
3165   DCHECK_EQ(flow_control_state_, FLOW_CONTROL_STREAM_AND_SESSION);
3166   DCHECK_GE(consume_size, 1u);
3167   DCHECK_LE(consume_size, static_cast<size_t>(kint32max));
3168
3169   IncreaseRecvWindowSize(static_cast<int32>(consume_size));
3170 }
3171
3172 void SpdySession::IncreaseRecvWindowSize(int32 delta_window_size) {
3173   DCHECK_EQ(flow_control_state_, FLOW_CONTROL_STREAM_AND_SESSION);
3174   DCHECK_GE(session_unacked_recv_window_bytes_, 0);
3175   DCHECK_GE(session_recv_window_size_, session_unacked_recv_window_bytes_);
3176   DCHECK_GE(delta_window_size, 1);
3177   // Check for overflow.
3178   DCHECK_LE(delta_window_size, kint32max - session_recv_window_size_);
3179
3180   session_recv_window_size_ += delta_window_size;
3181   net_log_.AddEvent(NetLog::TYPE_HTTP2_STREAM_UPDATE_RECV_WINDOW,
3182                     base::Bind(&NetLogSpdySessionWindowUpdateCallback,
3183                                delta_window_size, session_recv_window_size_));
3184
3185   session_unacked_recv_window_bytes_ += delta_window_size;
3186   if (session_unacked_recv_window_bytes_ >
3187       GetInitialWindowSize(protocol_) / 2) {
3188     SendWindowUpdateFrame(kSessionFlowControlStreamId,
3189                           session_unacked_recv_window_bytes_,
3190                           HIGHEST);
3191     session_unacked_recv_window_bytes_ = 0;
3192   }
3193 }
3194
3195 void SpdySession::DecreaseRecvWindowSize(int32 delta_window_size) {
3196   CHECK(in_io_loop_);
3197   DCHECK_EQ(flow_control_state_, FLOW_CONTROL_STREAM_AND_SESSION);
3198   DCHECK_GE(delta_window_size, 1);
3199
3200   // Since we never decrease the initial receive window size,
3201   // |delta_window_size| should never cause |recv_window_size_| to go
3202   // negative. If we do, the receive window isn't being respected.
3203   if (delta_window_size > session_recv_window_size_) {
3204     RecordProtocolErrorHistogram(PROTOCOL_ERROR_RECEIVE_WINDOW_VIOLATION);
3205     DoDrainSession(
3206         ERR_SPDY_FLOW_CONTROL_ERROR,
3207         "delta_window_size is " + base::IntToString(delta_window_size) +
3208             " in DecreaseRecvWindowSize, which is larger than the receive " +
3209             "window size of " + base::IntToString(session_recv_window_size_));
3210     return;
3211   }
3212
3213   session_recv_window_size_ -= delta_window_size;
3214   net_log_.AddEvent(NetLog::TYPE_HTTP2_SESSION_UPDATE_RECV_WINDOW,
3215                     base::Bind(&NetLogSpdySessionWindowUpdateCallback,
3216                                -delta_window_size, session_recv_window_size_));
3217 }
3218
3219 void SpdySession::QueueSendStalledStream(const SpdyStream& stream) {
3220   DCHECK(stream.send_stalled_by_flow_control());
3221   RequestPriority priority = stream.priority();
3222   CHECK_GE(priority, MINIMUM_PRIORITY);
3223   CHECK_LE(priority, MAXIMUM_PRIORITY);
3224   stream_send_unstall_queue_[priority].push_back(stream.stream_id());
3225 }
3226
3227 void SpdySession::ResumeSendStalledStreams() {
3228   DCHECK_EQ(flow_control_state_, FLOW_CONTROL_STREAM_AND_SESSION);
3229
3230   // We don't have to worry about new streams being queued, since
3231   // doing so would cause IsSendStalled() to return true. But we do
3232   // have to worry about streams being closed, as well as ourselves
3233   // being closed.
3234
3235   while (!IsSendStalled()) {
3236     size_t old_size = 0;
3237 #if DCHECK_IS_ON()
3238     old_size = GetTotalSize(stream_send_unstall_queue_);
3239 #endif
3240
3241     SpdyStreamId stream_id = PopStreamToPossiblyResume();
3242     if (stream_id == 0)
3243       break;
3244     ActiveStreamMap::const_iterator it = active_streams_.find(stream_id);
3245     // The stream may actually still be send-stalled after this (due
3246     // to its own send window) but that's okay -- it'll then be
3247     // resumed once its send window increases.
3248     if (it != active_streams_.end())
3249       it->second.stream->PossiblyResumeIfSendStalled();
3250
3251     // The size should decrease unless we got send-stalled again.
3252     if (!IsSendStalled())
3253       DCHECK_LT(GetTotalSize(stream_send_unstall_queue_), old_size);
3254   }
3255 }
3256
3257 SpdyStreamId SpdySession::PopStreamToPossiblyResume() {
3258   for (int i = MAXIMUM_PRIORITY; i >= MINIMUM_PRIORITY; --i) {
3259     std::deque<SpdyStreamId>* queue = &stream_send_unstall_queue_[i];
3260     if (!queue->empty()) {
3261       SpdyStreamId stream_id = queue->front();
3262       queue->pop_front();
3263       return stream_id;
3264     }
3265   }
3266   return 0;
3267 }
3268
3269 }  // namespace net