chrome/browser/io_thread.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 "chrome/browser/io_thread.h"
   6
   7 #include <vector>
   8
   9 #include "base/base64.h"
  10 #include "base/bind.h"
  11 #include "base/bind_helpers.h"
  12 #include "base/command_line.h"
  13 #include "base/compiler_specific.h"
  14 #include "base/debug/leak_tracker.h"
  15 #include "base/logging.h"
  16 #include "base/metrics/field_trial.h"
  17 #include "base/prefs/pref_registry_simple.h"
  18 #include "base/prefs/pref_service.h"
  19 #include "base/profiler/scoped_tracker.h"
  20 #include "base/stl_util.h"
  21 #include "base/strings/string_number_conversions.h"
  22 #include "base/strings/string_piece.h"
  23 #include "base/strings/string_split.h"
  24 #include "base/strings/string_util.h"
  25 #include "base/threading/sequenced_worker_pool.h"
  26 #include "base/threading/thread.h"
  27 #include "base/threading/worker_pool.h"
  28 #include "base/time/time.h"
  29 #include "base/trace_event/trace_event.h"
  30 #include "build/build_config.h"
  31 #include "chrome/browser/browser_process.h"
  32 #include "chrome/browser/net/async_dns_field_trial.h"
  33 #include "chrome/browser/net/chrome_net_log.h"
  34 #include "chrome/browser/net/chrome_network_delegate.h"
  35 #include "chrome/browser/net/connect_interceptor.h"
  36 #include "chrome/browser/net/dns_probe_service.h"
  37 #include "chrome/browser/net/pref_proxy_config_tracker.h"
  38 #include "chrome/browser/net/proxy_service_factory.h"
  39 #include "chrome/common/chrome_content_client.h"
  40 #include "chrome/common/chrome_switches.h"
  41 #include "chrome/common/chrome_version_info.h"
  42 #include "chrome/common/pref_names.h"
  43 #include "components/data_reduction_proxy/core/browser/data_reduction_proxy_prefs.h"
  44 #include "components/data_reduction_proxy/core/common/data_reduction_proxy_params.h"
  45 #include "components/policy/core/common/policy_service.h"
  46 #include "components/variations/variations_associated_data.h"
  47 #include "content/public/browser/browser_thread.h"
  48 #include "content/public/browser/cookie_store_factory.h"
  49 #include "net/base/host_mapping_rules.h"
  50 #include "net/base/net_util.h"
  51 #include "net/base/sdch_manager.h"
  52 #include "net/cert/cert_policy_enforcer.h"
  53 #include "net/cert/cert_verifier.h"
  54 #include "net/cert/cert_verify_proc.h"
  55 #include "net/cert/ct_known_logs.h"
  56 #include "net/cert/ct_known_logs_static.h"
  57 #include "net/cert/ct_log_verifier.h"
  58 #include "net/cert/ct_verifier.h"
  59 #include "net/cert/multi_log_ct_verifier.h"
  60 #include "net/cert/multi_threaded_cert_verifier.h"
  61 #include "net/cookies/cookie_store.h"
  62 #include "net/dns/host_cache.h"
  63 #include "net/dns/host_resolver.h"
  64 #include "net/dns/mapped_host_resolver.h"
  65 #include "net/ftp/ftp_network_layer.h"
  66 #include "net/http/http_auth_filter.h"
  67 #include "net/http/http_auth_handler_factory.h"
  68 #include "net/http/http_network_layer.h"
  69 #include "net/http/http_server_properties_impl.h"
  70 #include "net/proxy/proxy_config_service.h"
  71 #include "net/proxy/proxy_script_fetcher_impl.h"
  72 #include "net/proxy/proxy_service.h"
  73 #include "net/quic/crypto/crypto_protocol.h"
  74 #include "net/quic/quic_protocol.h"
  75 #include "net/quic/quic_utils.h"
  76 #include "net/socket/tcp_client_socket.h"
  77 #include "net/spdy/spdy_session.h"
  78 #include "net/ssl/channel_id_service.h"
  79 #include "net/ssl/default_channel_id_store.h"
  80 #include "net/url_request/data_protocol_handler.h"
  81 #include "net/url_request/file_protocol_handler.h"
  82 #include "net/url_request/ftp_protocol_handler.h"
  83 #include "net/url_request/static_http_user_agent_settings.h"
  84 #include "net/url_request/url_fetcher.h"
  85 #include "net/url_request/url_request_context.h"
  86 #include "net/url_request/url_request_context_getter.h"
  87 #include "net/url_request/url_request_job_factory_impl.h"
  88 #include "net/url_request/url_request_throttler_manager.h"
  89 #include "url/url_constants.h"
  90
  91 #if defined(ENABLE_CONFIGURATION_POLICY)
  92 #include "policy/policy_constants.h"
  93 #endif
  94
  95 #if defined(ENABLE_EXTENSIONS)
  96 #include "chrome/browser/extensions/event_router_forwarder.h"
  97 #endif
  98
  99 #if defined(USE_NSS) || defined(OS_IOS)
 100 #include "net/ocsp/nss_ocsp.h"
 101 #endif
 102
 103 #if defined(OS_ANDROID)
 104 #include "base/android/build_info.h"
 105 #endif
 106
 107 #if defined(OS_CHROMEOS)
 108 #include "chrome/browser/chromeos/net/cert_verify_proc_chromeos.h"
 109 #include "chromeos/network/host_resolver_impl_chromeos.h"
 110 #endif
 111
 112 using content::BrowserThread;
 113
 114 class SafeBrowsingURLRequestContext;
 115
 116 // The IOThread object must outlive any tasks posted to the IO thread before the
 117 // Quit task, so base::Bind() calls are not refcounted.
 118
 119 namespace {
 120
 121 const char kTCPFastOpenFieldTrialName[] = "TCPFastOpen";
 122 const char kTCPFastOpenHttpsEnabledGroupName[] = "HttpsEnabled";
 123
 124 const char kQuicFieldTrialName[] = "QUIC";
 125 const char kQuicFieldTrialEnabledGroupName[] = "Enabled";
 126 const char kQuicFieldTrialHttpsEnabledGroupName[] = "HttpsEnabled";
 127
 128 // The SPDY trial composes two different trial plus control groups:
 129 //  * A "holdback" group with SPDY disabled, and corresponding control
 130 //  (SPDY/3.1). The primary purpose of the holdback group is to encourage site
 131 //  operators to do feature detection rather than UA-sniffing. As such, this
 132 //  trial runs continuously.
 133 //  * A SPDY/4 experiment, for SPDY/4 (aka HTTP/2) vs SPDY/3.1 comparisons and
 134 //  eventual SPDY/4 deployment.
 135 const char kSpdyFieldTrialName[] = "SPDY";
 136 const char kSpdyFieldTrialHoldbackGroupNamePrefix[] = "SpdyDisabled";
 137 const char kSpdyFieldTrialSpdy31GroupNamePrefix[] = "Spdy31Enabled";
 138 const char kSpdyFieldTrialSpdy4GroupNamePrefix[] = "Spdy4Enabled";
 139 const char kSpdyFieldTrialParametrizedPrefix[] = "Parametrized";
 140
 141 // Field trial for Cache-Control: stale-while-revalidate directive.
 142 const char kStaleWhileRevalidateFieldTrialName[] = "StaleWhileRevalidate";
 143
 144 #if defined(OS_MACOSX) && !defined(OS_IOS)
 145 void ObserveKeychainEvents() {
 146   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 147   net::CertDatabase::GetInstance()->SetMessageLoopForKeychainEvents();
 148 }
 149 #endif
 150
 151 // Used for the "system" URLRequestContext.
 152 class SystemURLRequestContext : public net::URLRequestContext {
 153  public:
 154   SystemURLRequestContext() {
 155 #if defined(USE_NSS) || defined(OS_IOS)
 156     net::SetURLRequestContextForNSSHttpIO(this);
 157 #endif
 158   }
 159
 160  private:
 161   ~SystemURLRequestContext() override {
 162     AssertNoURLRequests();
 163 #if defined(USE_NSS) || defined(OS_IOS)
 164     net::SetURLRequestContextForNSSHttpIO(NULL);
 165 #endif
 166   }
 167 };
 168
 169 scoped_ptr<net::HostResolver> CreateGlobalHostResolver(net::NetLog* net_log) {
 170   TRACE_EVENT0("startup", "IOThread::CreateGlobalHostResolver");
 171   const base::CommandLine& command_line =
 172       *base::CommandLine::ForCurrentProcess();
 173
 174   net::HostResolver::Options options;
 175
 176   // Use the retry attempts override from the command-line, if any.
 177   if (command_line.HasSwitch(switches::kHostResolverRetryAttempts)) {
 178     std::string s =
 179         command_line.GetSwitchValueASCII(switches::kHostResolverRetryAttempts);
 180     // Parse the switch (it should be a non-negative integer).
 181     int n;
 182     if (base::StringToInt(s, &n) && n >= 0) {
 183       options.max_retry_attempts = static_cast<size_t>(n);
 184     } else {
 185       LOG(ERROR) << "Invalid switch for host resolver retry attempts: " << s;
 186     }
 187   }
 188
 189   scoped_ptr<net::HostResolver> global_host_resolver;
 190 #if defined OS_CHROMEOS
 191   global_host_resolver =
 192       chromeos::HostResolverImplChromeOS::CreateSystemResolver(options,
 193                                                                net_log);
 194 #else
 195   global_host_resolver =
 196       net::HostResolver::CreateSystemResolver(options, net_log);
 197 #endif
 198
 199   // Determine if we should disable IPv6 support.
 200   if (command_line.HasSwitch(switches::kEnableIPv6)) {
 201     // Disable IPv6 probing.
 202     global_host_resolver->SetDefaultAddressFamily(
 203         net::ADDRESS_FAMILY_UNSPECIFIED);
 204   } else if (command_line.HasSwitch(switches::kDisableIPv6)) {
 205     global_host_resolver->SetDefaultAddressFamily(net::ADDRESS_FAMILY_IPV4);
 206   }
 207
 208   // If hostname remappings were specified on the command-line, layer these
 209   // rules on top of the real host resolver. This allows forwarding all requests
 210   // through a designated test server.
 211   if (!command_line.HasSwitch(switches::kHostResolverRules))
 212     return global_host_resolver.Pass();
 213
 214   scoped_ptr<net::MappedHostResolver> remapped_resolver(
 215       new net::MappedHostResolver(global_host_resolver.Pass()));
 216   remapped_resolver->SetRulesFromString(
 217       command_line.GetSwitchValueASCII(switches::kHostResolverRules));
 218   return remapped_resolver.Pass();
 219 }
 220
 221 // TODO(willchan): Remove proxy script fetcher context since it's not necessary
 222 // now that I got rid of refcounting URLRequestContexts.
 223 // See IOThread::Globals for details.
 224 net::URLRequestContext*
 225 ConstructProxyScriptFetcherContext(IOThread::Globals* globals,
 226                                    net::NetLog* net_log) {
 227   net::URLRequestContext* context = new net::URLRequestContext;
 228   context->set_net_log(net_log);
 229   context->set_host_resolver(globals->host_resolver.get());
 230   context->set_cert_verifier(globals->cert_verifier.get());
 231   context->set_transport_security_state(
 232       globals->transport_security_state.get());
 233   context->set_cert_transparency_verifier(
 234       globals->cert_transparency_verifier.get());
 235   context->set_http_auth_handler_factory(
 236       globals->http_auth_handler_factory.get());
 237   context->set_proxy_service(globals->proxy_script_fetcher_proxy_service.get());
 238   context->set_http_transaction_factory(
 239       globals->proxy_script_fetcher_http_transaction_factory.get());
 240   context->set_job_factory(
 241       globals->proxy_script_fetcher_url_request_job_factory.get());
 242   context->set_cookie_store(globals->system_cookie_store.get());
 243   context->set_channel_id_service(
 244       globals->system_channel_id_service.get());
 245   context->set_network_delegate(globals->system_network_delegate.get());
 246   context->set_http_user_agent_settings(
 247       globals->http_user_agent_settings.get());
 248   // TODO(rtenneti): We should probably use HttpServerPropertiesManager for the
 249   // system URLRequestContext too. There's no reason this should be tied to a
 250   // profile.
 251   return context;
 252 }
 253
 254 net::URLRequestContext*
 255 ConstructSystemRequestContext(IOThread::Globals* globals,
 256                               net::NetLog* net_log) {
 257   net::URLRequestContext* context = new SystemURLRequestContext;
 258   context->set_net_log(net_log);
 259   context->set_host_resolver(globals->host_resolver.get());
 260   context->set_cert_verifier(globals->cert_verifier.get());
 261   context->set_transport_security_state(
 262       globals->transport_security_state.get());
 263   context->set_cert_transparency_verifier(
 264       globals->cert_transparency_verifier.get());
 265   context->set_http_auth_handler_factory(
 266       globals->http_auth_handler_factory.get());
 267   context->set_proxy_service(globals->system_proxy_service.get());
 268   context->set_http_transaction_factory(
 269       globals->system_http_transaction_factory.get());
 270   context->set_job_factory(globals->system_url_request_job_factory.get());
 271   context->set_cookie_store(globals->system_cookie_store.get());
 272   context->set_channel_id_service(
 273       globals->system_channel_id_service.get());
 274   context->set_throttler_manager(globals->throttler_manager.get());
 275   context->set_network_delegate(globals->system_network_delegate.get());
 276   context->set_http_user_agent_settings(
 277       globals->http_user_agent_settings.get());
 278   return context;
 279 }
 280
 281 int GetSwitchValueAsInt(const base::CommandLine& command_line,
 282                         const std::string& switch_name) {
 283   int value;
 284   if (!base::StringToInt(command_line.GetSwitchValueASCII(switch_name),
 285                          &value)) {
 286     return 0;
 287   }
 288   return value;
 289 }
 290
 291 // Returns the value associated with |key| in |params| or "" if the
 292 // key is not present in the map.
 293 const std::string& GetVariationParam(
 294     const std::map<std::string, std::string>& params,
 295     const std::string& key) {
 296   std::map<std::string, std::string>::const_iterator it = params.find(key);
 297   if (it == params.end())
 298     return base::EmptyString();
 299
 300   return it->second;
 301 }
 302
 303 // Return true if stale-while-revalidate support should be enabled.
 304 bool IsStaleWhileRevalidateEnabled(const base::CommandLine& command_line) {
 305   if (command_line.HasSwitch(switches::kEnableStaleWhileRevalidate))
 306     return true;
 307   const std::string group_name =
 308       base::FieldTrialList::FindFullName(kStaleWhileRevalidateFieldTrialName);
 309   return group_name == "Enabled";
 310 }
 311
 312 bool IsCertificateTransparencyRequiredForEV(
 313     const base::CommandLine& command_line) {
 314   const std::string group_name =
 315       base::FieldTrialList::FindFullName("CTRequiredForEVTrial");
 316   if (command_line.HasSwitch(
 317         switches::kDisableCertificateTransparencyRequirementForEV))
 318     return false;
 319
 320   return group_name == "RequirementEnforced";
 321 }
 322
 323 // Parse kUseSpdy command line flag options, which may contain the following:
 324 //
 325 //   "off"                      : Disables SPDY support entirely.
 326 //   "ssl"                      : Forces SPDY for all HTTPS requests.
 327 //   "no-ssl"                   : Forces SPDY for all HTTP requests.
 328 //   "no-ping"                  : Disables SPDY ping connection testing.
 329 //   "exclude=<host>"           : Disables SPDY support for the host <host>.
 330 //   "no-compress"              : Disables SPDY header compression.
 331 //   "no-alt-protocols          : Disables alternate protocol support.
 332 //   "force-alt-protocols       : Forces an alternate protocol of SPDY/3
 333 //                                on port 443.
 334 //   "single-domain"            : Forces all spdy traffic to a single domain.
 335 //   "init-max-streams=<limit>" : Specifies the maximum number of concurrent
 336 //                                streams for a SPDY session, unless the
 337 //                                specifies a different value via SETTINGS.
 338 void ConfigureSpdyGlobalsFromUseSpdyArgument(const std::string& mode,
 339                                              IOThread::Globals* globals) {
 340   static const char kOff[] = "off";
 341   static const char kSSL[] = "ssl";
 342   static const char kDisableSSL[] = "no-ssl";
 343   static const char kDisablePing[] = "no-ping";
 344   static const char kExclude[] = "exclude";  // Hosts to exclude
 345   static const char kDisableCompression[] = "no-compress";
 346   static const char kDisableAltProtocols[] = "no-alt-protocols";
 347   static const char kSingleDomain[] = "single-domain";
 348
 349   static const char kInitialMaxConcurrentStreams[] = "init-max-streams";
 350
 351   std::vector<std::string> spdy_options;
 352   base::SplitString(mode, ',', &spdy_options);
 353
 354   for (const std::string& element : spdy_options) {
 355     std::vector<std::string> name_value;
 356     base::SplitString(element, '=', &name_value);
 357     const std::string& option =
 358         name_value.size() > 0 ? name_value[0] : std::string();
 359     const std::string value =
 360         name_value.size() > 1 ? name_value[1] : std::string();
 361
 362     if (option == kOff) {
 363       net::HttpStreamFactory::set_spdy_enabled(false);
 364       continue;
 365     }
 366     if (option == kDisableSSL) {
 367       globals->spdy_default_protocol.set(net::kProtoSPDY31);
 368       globals->force_spdy_over_ssl.set(false);
 369       globals->force_spdy_always.set(true);
 370       continue;
 371     }
 372     if (option == kSSL) {
 373       globals->spdy_default_protocol.set(net::kProtoSPDY31);
 374       globals->force_spdy_over_ssl.set(true);
 375       globals->force_spdy_always.set(true);
 376       continue;
 377     }
 378     if (option == kDisablePing) {
 379       globals->enable_spdy_ping_based_connection_checking.set(false);
 380       continue;
 381     }
 382     if (option == kExclude) {
 383       globals->forced_spdy_exclusions.insert(
 384           net::HostPortPair::FromURL(GURL(value)));
 385       continue;
 386     }
 387     if (option == kDisableCompression) {
 388       globals->enable_spdy_compression.set(false);
 389       continue;
 390     }
 391     if (option == kDisableAltProtocols) {
 392       globals->use_alternate_protocols.set(false);
 393       continue;
 394     }
 395     if (option == kSingleDomain) {
 396       DVLOG(1) << "FORCING SINGLE DOMAIN";
 397       globals->force_spdy_single_domain.set(true);
 398       continue;
 399     }
 400     if (option == kInitialMaxConcurrentStreams) {
 401       int streams;
 402       if (base::StringToInt(value, &streams)) {
 403         globals->initial_max_spdy_concurrent_streams.set(streams);
 404         continue;
 405       }
 406     }
 407     LOG(DFATAL) << "Unrecognized spdy option: " << option;
 408   }
 409 }
 410
 411 }  // namespace
 412
 413 class IOThread::LoggingNetworkChangeObserver
 414     : public net::NetworkChangeNotifier::IPAddressObserver,
 415       public net::NetworkChangeNotifier::ConnectionTypeObserver,
 416       public net::NetworkChangeNotifier::NetworkChangeObserver {
 417  public:
 418   // |net_log| must remain valid throughout our lifetime.
 419   explicit LoggingNetworkChangeObserver(net::NetLog* net_log)
 420       : net_log_(net_log) {
 421     net::NetworkChangeNotifier::AddIPAddressObserver(this);
 422     net::NetworkChangeNotifier::AddConnectionTypeObserver(this);
 423     net::NetworkChangeNotifier::AddNetworkChangeObserver(this);
 424   }
 425
 426   ~LoggingNetworkChangeObserver() override {
 427     net::NetworkChangeNotifier::RemoveIPAddressObserver(this);
 428     net::NetworkChangeNotifier::RemoveConnectionTypeObserver(this);
 429     net::NetworkChangeNotifier::RemoveNetworkChangeObserver(this);
 430   }
 431
 432   // NetworkChangeNotifier::IPAddressObserver implementation.
 433   void OnIPAddressChanged() override {
 434     VLOG(1) << "Observed a change to the network IP addresses";
 435
 436     net_log_->AddGlobalEntry(net::NetLog::TYPE_NETWORK_IP_ADDRESSES_CHANGED);
 437   }
 438
 439   // NetworkChangeNotifier::ConnectionTypeObserver implementation.
 440   void OnConnectionTypeChanged(
 441       net::NetworkChangeNotifier::ConnectionType type) override {
 442     std::string type_as_string =
 443         net::NetworkChangeNotifier::ConnectionTypeToString(type);
 444
 445     VLOG(1) << "Observed a change to network connectivity state "
 446             << type_as_string;
 447
 448     net_log_->AddGlobalEntry(
 449         net::NetLog::TYPE_NETWORK_CONNECTIVITY_CHANGED,
 450         net::NetLog::StringCallback("new_connection_type", &type_as_string));
 451   }
 452
 453   // NetworkChangeNotifier::NetworkChangeObserver implementation.
 454   void OnNetworkChanged(
 455       net::NetworkChangeNotifier::ConnectionType type) override {
 456     std::string type_as_string =
 457         net::NetworkChangeNotifier::ConnectionTypeToString(type);
 458
 459     VLOG(1) << "Observed a network change to state " << type_as_string;
 460
 461     net_log_->AddGlobalEntry(
 462         net::NetLog::TYPE_NETWORK_CHANGED,
 463         net::NetLog::StringCallback("new_connection_type", &type_as_string));
 464   }
 465
 466  private:
 467   net::NetLog* net_log_;
 468   DISALLOW_COPY_AND_ASSIGN(LoggingNetworkChangeObserver);
 469 };
 470
 471 class SystemURLRequestContextGetter : public net::URLRequestContextGetter {
 472  public:
 473   explicit SystemURLRequestContextGetter(IOThread* io_thread);
 474
 475   // Implementation for net::UrlRequestContextGetter.
 476   net::URLRequestContext* GetURLRequestContext() override;
 477   scoped_refptr<base::SingleThreadTaskRunner> GetNetworkTaskRunner()
 478       const override;
 479
 480  protected:
 481   ~SystemURLRequestContextGetter() override;
 482
 483  private:
 484   IOThread* const io_thread_;  // Weak pointer, owned by BrowserProcess.
 485   scoped_refptr<base::SingleThreadTaskRunner> network_task_runner_;
 486
 487   base::debug::LeakTracker<SystemURLRequestContextGetter> leak_tracker_;
 488 };
 489
 490 SystemURLRequestContextGetter::SystemURLRequestContextGetter(
 491     IOThread* io_thread)
 492     : io_thread_(io_thread),
 493       network_task_runner_(
 494           BrowserThread::GetMessageLoopProxyForThread(BrowserThread::IO)) {
 495 }
 496
 497 SystemURLRequestContextGetter::~SystemURLRequestContextGetter() {}
 498
 499 net::URLRequestContext* SystemURLRequestContextGetter::GetURLRequestContext() {
 500   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 501   DCHECK(io_thread_->globals()->system_request_context.get());
 502
 503   return io_thread_->globals()->system_request_context.get();
 504 }
 505
 506 scoped_refptr<base::SingleThreadTaskRunner>
 507 SystemURLRequestContextGetter::GetNetworkTaskRunner() const {
 508   return network_task_runner_;
 509 }
 510
 511 IOThread::Globals::
 512 SystemRequestContextLeakChecker::SystemRequestContextLeakChecker(
 513     Globals* globals)
 514     : globals_(globals) {
 515   DCHECK(globals_);
 516 }
 517
 518 IOThread::Globals::
 519 SystemRequestContextLeakChecker::~SystemRequestContextLeakChecker() {
 520   if (globals_->system_request_context.get())
 521     globals_->system_request_context->AssertNoURLRequests();
 522 }
 523
 524 IOThread::Globals::Globals()
 525     : system_request_context_leak_checker(this),
 526       ignore_certificate_errors(false),
 527       use_stale_while_revalidate(false),
 528       testing_fixed_http_port(0),
 529       testing_fixed_https_port(0),
 530       enable_user_alternate_protocol_ports(false) {
 531 }
 532
 533 IOThread::Globals::~Globals() {}
 534
 535 // |local_state| is passed in explicitly in order to (1) reduce implicit
 536 // dependencies and (2) make IOThread more flexible for testing.
 537 IOThread::IOThread(
 538     PrefService* local_state,
 539     policy::PolicyService* policy_service,
 540     ChromeNetLog* net_log,
 541     extensions::EventRouterForwarder* extension_event_router_forwarder)
 542     : net_log_(net_log),
 543 #if defined(ENABLE_EXTENSIONS)
 544       extension_event_router_forwarder_(extension_event_router_forwarder),
 545 #endif
 546       globals_(NULL),
 547       is_spdy_disabled_by_policy_(false),
 548       creation_time_(base::TimeTicks::Now()),
 549       weak_factory_(this) {
 550   auth_schemes_ = local_state->GetString(prefs::kAuthSchemes);
 551   negotiate_disable_cname_lookup_ = local_state->GetBoolean(
 552       prefs::kDisableAuthNegotiateCnameLookup);
 553   negotiate_enable_port_ = local_state->GetBoolean(
 554       prefs::kEnableAuthNegotiatePort);
 555   auth_server_whitelist_ = local_state->GetString(prefs::kAuthServerWhitelist);
 556   auth_delegate_whitelist_ = local_state->GetString(
 557       prefs::kAuthNegotiateDelegateWhitelist);
 558   gssapi_library_name_ = local_state->GetString(prefs::kGSSAPILibraryName);
 559   pref_proxy_config_tracker_.reset(
 560       ProxyServiceFactory::CreatePrefProxyConfigTrackerOfLocalState(
 561           local_state));
 562   ChromeNetworkDelegate::InitializePrefsOnUIThread(
 563       &system_enable_referrers_,
 564       NULL,
 565       NULL,
 566       NULL,
 567       NULL,
 568       local_state);
 569   ssl_config_service_manager_.reset(
 570       SSLConfigServiceManager::CreateDefaultManager(local_state));
 571
 572   base::Value* dns_client_enabled_default = new base::FundamentalValue(
 573       chrome_browser_net::ConfigureAsyncDnsFieldTrial());
 574   local_state->SetDefaultPrefValue(prefs::kBuiltInDnsClientEnabled,
 575                                    dns_client_enabled_default);
 576   chrome_browser_net::LogAsyncDnsPrefSource(
 577       local_state->FindPreference(prefs::kBuiltInDnsClientEnabled));
 578
 579   dns_client_enabled_.Init(prefs::kBuiltInDnsClientEnabled,
 580                            local_state,
 581                            base::Bind(&IOThread::UpdateDnsClientEnabled,
 582                                       base::Unretained(this)));
 583   dns_client_enabled_.MoveToThread(
 584       BrowserThread::GetMessageLoopProxyForThread(BrowserThread::IO));
 585
 586   quick_check_enabled_.Init(prefs::kQuickCheckEnabled,
 587                             local_state);
 588   quick_check_enabled_.MoveToThread(
 589       BrowserThread::GetMessageLoopProxyForThread(BrowserThread::IO));
 590
 591 #if defined(ENABLE_CONFIGURATION_POLICY)
 592   is_spdy_disabled_by_policy_ = policy_service->GetPolicies(
 593       policy::PolicyNamespace(policy::POLICY_DOMAIN_CHROME, std::string())).Get(
 594           policy::key::kDisableSpdy) != NULL;
 595 #endif  // ENABLE_CONFIGURATION_POLICY
 596
 597   BrowserThread::SetDelegate(BrowserThread::IO, this);
 598 }
 599
 600 IOThread::~IOThread() {
 601   // This isn't needed for production code, but in tests, IOThread may
 602   // be multiply constructed.
 603   BrowserThread::SetDelegate(BrowserThread::IO, NULL);
 604
 605   pref_proxy_config_tracker_->DetachFromPrefService();
 606   DCHECK(!globals_);
 607 }
 608
 609 IOThread::Globals* IOThread::globals() {
 610   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 611   return globals_;
 612 }
 613
 614 void IOThread::SetGlobalsForTesting(Globals* globals) {
 615   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 616   DCHECK(!globals || !globals_);
 617   globals_ = globals;
 618 }
 619
 620 ChromeNetLog* IOThread::net_log() {
 621   return net_log_;
 622 }
 623
 624 void IOThread::ChangedToOnTheRecord() {
 625   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 626   BrowserThread::PostTask(
 627       BrowserThread::IO,
 628       FROM_HERE,
 629       base::Bind(&IOThread::ChangedToOnTheRecordOnIOThread,
 630                  base::Unretained(this)));
 631 }
 632
 633 net::URLRequestContextGetter* IOThread::system_url_request_context_getter() {
 634   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 635   if (!system_url_request_context_getter_.get()) {
 636     InitSystemRequestContext();
 637   }
 638   return system_url_request_context_getter_.get();
 639 }
 640
 641 void IOThread::Init() {
 642   // Prefer to use InitAsync unless you need initialization to block
 643   // the UI thread
 644 }
 645
 646 void IOThread::InitAsync() {
 647   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 648   // is fixed.
 649   tracked_objects::ScopedTracker tracking_profile1(
 650       FROM_HERE_WITH_EXPLICIT_FUNCTION("466432 IOThread::InitAsync::Start"));
 651   TRACE_EVENT0("startup", "IOThread::InitAsync");
 652   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 653
 654 #if defined(USE_NSS) || defined(OS_IOS)
 655   net::SetMessageLoopForNSSHttpIO();
 656 #endif
 657
 658   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 659   // is fixed.
 660   tracked_objects::ScopedTracker tracking_profile2(
 661       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 662           "466432 IOThread::InitAsync::CommandLineForCurrentProcess"));
 663   const base::CommandLine& command_line =
 664       *base::CommandLine::ForCurrentProcess();
 665
 666   DCHECK(!globals_);
 667   globals_ = new Globals;
 668
 669   // Add an observer that will emit network change events to the ChromeNetLog.
 670   // Assuming NetworkChangeNotifier dispatches in FIFO order, we should be
 671   // logging the network change before other IO thread consumers respond to it.
 672   network_change_observer_.reset(
 673       new LoggingNetworkChangeObserver(net_log_));
 674
 675   // Setup the HistogramWatcher to run on the IO thread.
 676   net::NetworkChangeNotifier::InitHistogramWatcher();
 677
 678 #if defined(ENABLE_EXTENSIONS)
 679   globals_->extension_event_router_forwarder =
 680       extension_event_router_forwarder_;
 681 #endif
 682
 683   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 684   // is fixed.
 685   tracked_objects::ScopedTracker tracking_profile3(
 686       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 687           "466432 IOThread::InitAsync::ChromeNetworkDelegate"));
 688   scoped_ptr<ChromeNetworkDelegate> chrome_network_delegate(
 689       new ChromeNetworkDelegate(extension_event_router_forwarder(),
 690                                 &system_enable_referrers_));
 691
 692 #if defined(ENABLE_EXTENSIONS)
 693   if (command_line.HasSwitch(switches::kDisableExtensionsHttpThrottling))
 694     chrome_network_delegate->NeverThrottleRequests();
 695 #endif
 696
 697   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 698   // is fixed.
 699   tracked_objects::ScopedTracker tracking_profile4(
 700       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 701           "466432 IOThread::InitAsync::CreateGlobalHostResolver"));
 702   globals_->system_network_delegate = chrome_network_delegate.Pass();
 703   globals_->host_resolver = CreateGlobalHostResolver(net_log_);
 704   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 705   // is fixed.
 706   tracked_objects::ScopedTracker tracking_profile5(
 707       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 708           "466432 IOThread::InitAsync::UpdateDnsClientEnabled::Start"));
 709   UpdateDnsClientEnabled();
 710   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 711   // is fixed.
 712   tracked_objects::ScopedTracker tracking_profile6(
 713       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 714           "466432 IOThread::InitAsync::UpdateDnsClientEnabled::End"));
 715 #if defined(OS_CHROMEOS)
 716   // Creates a CertVerifyProc that doesn't allow any profile-provided certs.
 717   globals_->cert_verifier.reset(new net::MultiThreadedCertVerifier(
 718       new chromeos::CertVerifyProcChromeOS()));
 719 #else
 720   globals_->cert_verifier.reset(new net::MultiThreadedCertVerifier(
 721       net::CertVerifyProc::CreateDefault()));
 722 #endif
 723
 724   globals_->transport_security_state.reset(new net::TransportSecurityState());
 725
 726   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 727   // is fixed.
 728   tracked_objects::ScopedTracker tracking_profile7(
 729       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 730           "466432 IOThread::InitAsync::CreateMultiLogVerifier"));
 731   net::MultiLogCTVerifier* ct_verifier = new net::MultiLogCTVerifier();
 732   globals_->cert_transparency_verifier.reset(ct_verifier);
 733
 734   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 735   // is fixed.
 736   tracked_objects::ScopedTracker tracking_profile8(
 737       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 738           "466432 IOThread::InitAsync::CreateLogVerifiers::Start"));
 739   // Add built-in logs
 740   ct_verifier->AddLogs(net::ct::CreateLogVerifiersForKnownLogs());
 741   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 742   // is fixed.
 743   tracked_objects::ScopedTracker tracking_profile9(
 744       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 745           "466432 IOThread::InitAsync::CreateLogVerifiers::End"));
 746
 747   // Add logs from command line
 748   if (command_line.HasSwitch(switches::kCertificateTransparencyLog)) {
 749     std::string switch_value = command_line.GetSwitchValueASCII(
 750         switches::kCertificateTransparencyLog);
 751     std::vector<std::string> logs;
 752     base::SplitString(switch_value, ',', &logs);
 753     for (std::vector<std::string>::iterator it = logs.begin(); it != logs.end();
 754          ++it) {
 755       const std::string& curr_log = *it;
 756       size_t delim_pos = curr_log.find(":");
 757       CHECK(delim_pos != std::string::npos)
 758           << "CT log description not provided (switch format"
 759              " is 'description:base64_key')";
 760       std::string log_description(curr_log.substr(0, delim_pos));
 761       std::string ct_public_key_data;
 762       CHECK(base::Base64Decode(curr_log.substr(delim_pos + 1),
 763                                &ct_public_key_data))
 764           << "Unable to decode CT public key.";
 765       scoped_ptr<net::CTLogVerifier> external_log_verifier(
 766           net::CTLogVerifier::Create(ct_public_key_data, log_description));
 767       CHECK(external_log_verifier) << "Unable to parse CT public key.";
 768       VLOG(1) << "Adding log with description " << log_description;
 769       ct_verifier->AddLog(external_log_verifier.Pass());
 770     }
 771   }
 772
 773   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 774   // is fixed.
 775   tracked_objects::ScopedTracker tracking_profile10(
 776       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 777           "466432 IOThread::InitAsync::CertPolicyEnforcer"));
 778   net::CertPolicyEnforcer* policy_enforcer = NULL;
 779   policy_enforcer = new net::CertPolicyEnforcer(
 780       IsCertificateTransparencyRequiredForEV(command_line));
 781   globals_->cert_policy_enforcer.reset(policy_enforcer);
 782
 783   globals_->ssl_config_service = GetSSLConfigService();
 784
 785   globals_->http_auth_handler_factory.reset(CreateDefaultAuthHandlerFactory(
 786       globals_->host_resolver.get()));
 787   globals_->http_server_properties.reset(new net::HttpServerPropertiesImpl());
 788   // For the ProxyScriptFetcher, we use a direct ProxyService.
 789   globals_->proxy_script_fetcher_proxy_service.reset(
 790       net::ProxyService::CreateDirectWithNetLog(net_log_));
 791   // In-memory cookie store.
 792   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 793   // is fixed.
 794   tracked_objects::ScopedTracker tracking_profile11(
 795       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 796           "466432 IOThread::InitAsync::CreateCookieStore::Start"));
 797   globals_->system_cookie_store =
 798         content::CreateCookieStore(content::CookieStoreConfig());
 799   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 800   // is fixed.
 801   tracked_objects::ScopedTracker tracking_profile12(
 802       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 803           "466432 IOThread::InitAsync::CreateCookieStore::End"));
 804   // In-memory channel ID store.
 805   globals_->system_channel_id_service.reset(
 806       new net::ChannelIDService(
 807           new net::DefaultChannelIDStore(NULL),
 808           base::WorkerPool::GetTaskRunner(true)));
 809   globals_->dns_probe_service.reset(new chrome_browser_net::DnsProbeService());
 810   globals_->host_mapping_rules.reset(new net::HostMappingRules());
 811   globals_->http_user_agent_settings.reset(
 812       new net::StaticHttpUserAgentSettings(std::string(), GetUserAgent()));
 813   if (command_line.HasSwitch(switches::kHostRules)) {
 814     TRACE_EVENT_BEGIN0("startup", "IOThread::InitAsync:SetRulesFromString");
 815     globals_->host_mapping_rules->SetRulesFromString(
 816         command_line.GetSwitchValueASCII(switches::kHostRules));
 817     TRACE_EVENT_END0("startup", "IOThread::InitAsync:SetRulesFromString");
 818   }
 819   if (command_line.HasSwitch(switches::kIgnoreCertificateErrors))
 820     globals_->ignore_certificate_errors = true;
 821   globals_->use_stale_while_revalidate =
 822       IsStaleWhileRevalidateEnabled(command_line);
 823   if (command_line.HasSwitch(switches::kTestingFixedHttpPort)) {
 824     globals_->testing_fixed_http_port =
 825         GetSwitchValueAsInt(command_line, switches::kTestingFixedHttpPort);
 826   }
 827   if (command_line.HasSwitch(switches::kTestingFixedHttpsPort)) {
 828     globals_->testing_fixed_https_port =
 829         GetSwitchValueAsInt(command_line, switches::kTestingFixedHttpsPort);
 830   }
 831   ConfigureQuic(command_line);
 832   if (command_line.HasSwitch(
 833           switches::kEnableUserAlternateProtocolPorts)) {
 834     globals_->enable_user_alternate_protocol_ports = true;
 835   }
 836   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 837   // is fixed.
 838   tracked_objects::ScopedTracker tracking_profile13(
 839       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 840           "466432 IOThread::InitAsync::InitializeNetworkOptions"));
 841   InitializeNetworkOptions(command_line);
 842
 843   net::HttpNetworkSession::Params session_params;
 844   InitializeNetworkSessionParams(&session_params);
 845   session_params.net_log = net_log_;
 846   session_params.proxy_service =
 847       globals_->proxy_script_fetcher_proxy_service.get();
 848
 849   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 850   // is fixed.
 851   tracked_objects::ScopedTracker tracking_profile14(
 852       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 853           "466432 IOThread::InitAsync::HttpNetorkSession::Start"));
 854   TRACE_EVENT_BEGIN0("startup", "IOThread::InitAsync:HttpNetworkSession");
 855   scoped_refptr<net::HttpNetworkSession> network_session(
 856       new net::HttpNetworkSession(session_params));
 857   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 858   // is fixed.
 859   tracked_objects::ScopedTracker tracking_profile15(
 860       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 861           "466432 IOThread::InitAsync::HttpNetorkSession::End"));
 862   globals_->proxy_script_fetcher_http_transaction_factory
 863       .reset(new net::HttpNetworkLayer(network_session.get()));
 864   TRACE_EVENT_END0("startup", "IOThread::InitAsync:HttpNetworkSession");
 865   scoped_ptr<net::URLRequestJobFactoryImpl> job_factory(
 866       new net::URLRequestJobFactoryImpl());
 867
 868   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 869   // is fixed.
 870   tracked_objects::ScopedTracker tracking_profile16(
 871       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 872           "466432 IOThread::InitAsync::SetProtocolHandler"));
 873   job_factory->SetProtocolHandler(url::kDataScheme,
 874                                   new net::DataProtocolHandler());
 875   job_factory->SetProtocolHandler(
 876       url::kFileScheme,
 877       new net::FileProtocolHandler(
 878           content::BrowserThread::GetBlockingPool()->
 879               GetTaskRunnerWithShutdownBehavior(
 880                   base::SequencedWorkerPool::SKIP_ON_SHUTDOWN)));
 881 #if !defined(DISABLE_FTP_SUPPORT)
 882   globals_->proxy_script_fetcher_ftp_transaction_factory.reset(
 883       new net::FtpNetworkLayer(globals_->host_resolver.get()));
 884   job_factory->SetProtocolHandler(
 885       url::kFtpScheme,
 886       new net::FtpProtocolHandler(
 887           globals_->proxy_script_fetcher_ftp_transaction_factory.get()));
 888 #endif
 889   globals_->proxy_script_fetcher_url_request_job_factory = job_factory.Pass();
 890
 891   globals_->throttler_manager.reset(new net::URLRequestThrottlerManager());
 892   globals_->throttler_manager->set_net_log(net_log_);
 893   // Always done in production, disabled only for unit tests.
 894   globals_->throttler_manager->set_enable_thread_checks(true);
 895
 896   globals_->proxy_script_fetcher_context.reset(
 897       ConstructProxyScriptFetcherContext(globals_, net_log_));
 898
 899 #if defined(OS_MACOSX) && !defined(OS_IOS)
 900   // Start observing Keychain events. This needs to be done on the UI thread,
 901   // as Keychain services requires a CFRunLoop.
 902   BrowserThread::PostTask(BrowserThread::UI,
 903                           FROM_HERE,
 904                           base::Bind(&ObserveKeychainEvents));
 905 #endif
 906
 907   // InitSystemRequestContext turns right around and posts a task back
 908   // to the IO thread, so we can't let it run until we know the IO
 909   // thread has started.
 910   //
 911   // Note that since we are at BrowserThread::Init time, the UI thread
 912   // is blocked waiting for the thread to start.  Therefore, posting
 913   // this task to the main thread's message loop here is guaranteed to
 914   // get it onto the message loop while the IOThread object still
 915   // exists.  However, the message might not be processed on the UI
 916   // thread until after IOThread is gone, so use a weak pointer.
 917   BrowserThread::PostTask(BrowserThread::UI,
 918                           FROM_HERE,
 919                           base::Bind(&IOThread::InitSystemRequestContext,
 920                                      weak_factory_.GetWeakPtr()));
 921 }
 922
 923 void IOThread::CleanUp() {
 924   base::debug::LeakTracker<SafeBrowsingURLRequestContext>::CheckForLeaks();
 925
 926 #if defined(USE_NSS) || defined(OS_IOS)
 927   net::ShutdownNSSHttpIO();
 928 #endif
 929
 930   system_url_request_context_getter_ = NULL;
 931
 932   // Release objects that the net::URLRequestContext could have been pointing
 933   // to.
 934
 935   // Shutdown the HistogramWatcher on the IO thread.
 936   net::NetworkChangeNotifier::ShutdownHistogramWatcher();
 937
 938   // This must be reset before the ChromeNetLog is destroyed.
 939   network_change_observer_.reset();
 940
 941   system_proxy_config_service_.reset();
 942
 943   delete globals_;
 944   globals_ = NULL;
 945
 946   base::debug::LeakTracker<SystemURLRequestContextGetter>::CheckForLeaks();
 947 }
 948
 949 void IOThread::InitializeNetworkOptions(const base::CommandLine& command_line) {
 950   // Only handle use-spdy command line flags if "spdy.disabled" preference is
 951   // not disabled via policy.
 952   if (is_spdy_disabled_by_policy_) {
 953     base::FieldTrial* trial = base::FieldTrialList::Find(kSpdyFieldTrialName);
 954     if (trial)
 955       trial->Disable();
 956   } else {
 957     std::string group = base::FieldTrialList::FindFullName(kSpdyFieldTrialName);
 958     VariationParameters params;
 959     if (!variations::GetVariationParams(kSpdyFieldTrialName, &params)) {
 960       params.clear();
 961     }
 962     ConfigureSpdyGlobals(command_line, group, params, globals_);
 963   }
 964
 965   ConfigureTCPFastOpen(command_line);
 966   ConfigureSdch();
 967
 968   // TODO(rch): Make the client socket factory a per-network session
 969   // instance, constructed from a NetworkSession::Params, to allow us
 970   // to move this option to IOThread::Globals &
 971   // HttpNetworkSession::Params.
 972 }
 973
 974 void IOThread::ConfigureTCPFastOpen(const base::CommandLine& command_line) {
 975   const std::string trial_group =
 976       base::FieldTrialList::FindFullName(kTCPFastOpenFieldTrialName);
 977   if (trial_group == kTCPFastOpenHttpsEnabledGroupName)
 978     globals_->enable_tcp_fast_open_for_ssl.set(true);
 979   bool always_enable_if_supported =
 980       command_line.HasSwitch(switches::kEnableTcpFastOpen);
 981   // Check for OS support of TCP FastOpen, and turn it on for all connections
 982   // if indicated by user.
 983   net::CheckSupportAndMaybeEnableTCPFastOpen(always_enable_if_supported);
 984 }
 985
 986 void IOThread::ConfigureSdch() {
 987   // Check SDCH field trial.  Default is now that everything is enabled,
 988   // so provide options for disabling HTTPS or all of SDCH.
 989   const char kSdchFieldTrialName[] = "SDCH";
 990   const char kEnabledHttpOnlyGroupName[] = "EnabledHttpOnly";
 991   const char kDisabledAllGroupName[] = "DisabledAll";
 992
 993   // Store in a string on return to keep underlying storage for
 994   // StringPiece stable.
 995   std::string sdch_trial_group_string =
 996       base::FieldTrialList::FindFullName(kSdchFieldTrialName);
 997   base::StringPiece sdch_trial_group(sdch_trial_group_string);
 998   if (sdch_trial_group.starts_with(kEnabledHttpOnlyGroupName)) {
 999     net::SdchManager::EnableSdchSupport(true);
1000     net::SdchManager::EnableSecureSchemeSupport(false);
1001   } else if (sdch_trial_group.starts_with(kDisabledAllGroupName)) {
1002     net::SdchManager::EnableSdchSupport(false);
1003   }
1004 }
1005
1006 // static
1007 void IOThread::ConfigureSpdyGlobals(
1008     const base::CommandLine& command_line,
1009     base::StringPiece spdy_trial_group,
1010     const VariationParameters& spdy_trial_params,
1011     IOThread::Globals* globals) {
1012   if (command_line.HasSwitch(switches::kTrustedSpdyProxy)) {
1013     globals->trusted_spdy_proxy.set(
1014         command_line.GetSwitchValueASCII(switches::kTrustedSpdyProxy));
1015   }
1016   if (command_line.HasSwitch(switches::kIgnoreUrlFetcherCertRequests))
1017     net::URLFetcher::SetIgnoreCertificateRequests(true);
1018
1019   if (command_line.HasSwitch(switches::kUseSpdy)) {
1020     std::string spdy_mode =
1021         command_line.GetSwitchValueASCII(switches::kUseSpdy);
1022     ConfigureSpdyGlobalsFromUseSpdyArgument(spdy_mode, globals);
1023     return;
1024   }
1025
1026   globals->next_protos.clear();
1027   globals->next_protos.push_back(net::kProtoHTTP11);
1028   bool enable_quic = false;
1029   globals->enable_quic.CopyToIfSet(&enable_quic);
1030   if (enable_quic) {
1031     globals->next_protos.push_back(net::kProtoQUIC1SPDY3);
1032   }
1033
1034   if (command_line.HasSwitch(switches::kEnableSpdy4)) {
1035     globals->next_protos.push_back(net::kProtoSPDY31);
1036     globals->next_protos.push_back(net::kProtoSPDY4_14);
1037     globals->next_protos.push_back(net::kProtoSPDY4);
1038     globals->use_alternate_protocols.set(true);
1039     return;
1040   }
1041   if (command_line.HasSwitch(switches::kEnableNpnHttpOnly)) {
1042     globals->use_alternate_protocols.set(false);
1043     return;
1044   }
1045
1046   // No SPDY command-line flags have been specified. Examine trial groups.
1047   if (spdy_trial_group.starts_with(kSpdyFieldTrialHoldbackGroupNamePrefix)) {
1048     net::HttpStreamFactory::set_spdy_enabled(false);
1049     return;
1050   }
1051   if (spdy_trial_group.starts_with(kSpdyFieldTrialSpdy31GroupNamePrefix)) {
1052     globals->next_protos.push_back(net::kProtoSPDY31);
1053     globals->use_alternate_protocols.set(true);
1054     return;
1055   }
1056   if (spdy_trial_group.starts_with(kSpdyFieldTrialSpdy4GroupNamePrefix)) {
1057     globals->next_protos.push_back(net::kProtoSPDY31);
1058     globals->next_protos.push_back(net::kProtoSPDY4_14);
1059     globals->next_protos.push_back(net::kProtoSPDY4);
1060     globals->use_alternate_protocols.set(true);
1061     return;
1062   }
1063   if (spdy_trial_group.starts_with(kSpdyFieldTrialParametrizedPrefix)) {
1064     bool spdy_enabled = false;
1065     if (LowerCaseEqualsASCII(
1066             GetVariationParam(spdy_trial_params, "enable_spdy31"), "true")) {
1067       globals->next_protos.push_back(net::kProtoSPDY31);
1068       spdy_enabled = true;
1069     }
1070     if (LowerCaseEqualsASCII(
1071             GetVariationParam(spdy_trial_params, "enable_http2_14"), "true")) {
1072       globals->next_protos.push_back(net::kProtoSPDY4_14);
1073       spdy_enabled = true;
1074     }
1075     if (LowerCaseEqualsASCII(
1076             GetVariationParam(spdy_trial_params, "enable_http2"), "true")) {
1077       globals->next_protos.push_back(net::kProtoSPDY4);
1078       spdy_enabled = true;
1079     }
1080     // TODO(bnc): HttpStreamFactory::spdy_enabled_ is redundant with
1081     // globals->next_protos, can it be eliminated?
1082     net::HttpStreamFactory::set_spdy_enabled(spdy_enabled);
1083     globals->use_alternate_protocols.set(true);
1084     return;
1085   }
1086
1087   // By default, enable HTTP/2.
1088   globals->next_protos.push_back(net::kProtoSPDY31);
1089   globals->next_protos.push_back(net::kProtoSPDY4_14);
1090   globals->next_protos.push_back(net::kProtoSPDY4);
1091   globals->use_alternate_protocols.set(true);
1092 }
1093
1094 // static
1095 void IOThread::RegisterPrefs(PrefRegistrySimple* registry) {
1096   registry->RegisterStringPref(prefs::kAuthSchemes,
1097                                "basic,digest,ntlm,negotiate,"
1098                                "spdyproxy");
1099   registry->RegisterBooleanPref(prefs::kDisableAuthNegotiateCnameLookup, false);
1100   registry->RegisterBooleanPref(prefs::kEnableAuthNegotiatePort, false);
1101   registry->RegisterStringPref(prefs::kAuthServerWhitelist, std::string());
1102   registry->RegisterStringPref(prefs::kAuthNegotiateDelegateWhitelist,
1103                                std::string());
1104   registry->RegisterStringPref(prefs::kGSSAPILibraryName, std::string());
1105   registry->RegisterStringPref(
1106       data_reduction_proxy::prefs::kDataReductionProxy, std::string());
1107   registry->RegisterBooleanPref(prefs::kEnableReferrers, true);
1108   data_reduction_proxy::RegisterPrefs(registry);
1109   registry->RegisterBooleanPref(prefs::kBuiltInDnsClientEnabled, true);
1110   registry->RegisterBooleanPref(prefs::kQuickCheckEnabled, true);
1111 }
1112
1113 net::HttpAuthHandlerFactory* IOThread::CreateDefaultAuthHandlerFactory(
1114     net::HostResolver* resolver) {
1115   net::HttpAuthFilterWhitelist* auth_filter_default_credentials = NULL;
1116   if (!auth_server_whitelist_.empty()) {
1117     auth_filter_default_credentials =
1118         new net::HttpAuthFilterWhitelist(auth_server_whitelist_);
1119   }
1120   net::HttpAuthFilterWhitelist* auth_filter_delegate = NULL;
1121   if (!auth_delegate_whitelist_.empty()) {
1122     auth_filter_delegate =
1123         new net::HttpAuthFilterWhitelist(auth_delegate_whitelist_);
1124   }
1125   globals_->url_security_manager.reset(
1126       net::URLSecurityManager::Create(auth_filter_default_credentials,
1127                                       auth_filter_delegate));
1128   std::vector<std::string> supported_schemes;
1129   base::SplitString(auth_schemes_, ',', &supported_schemes);
1130
1131   scoped_ptr<net::HttpAuthHandlerRegistryFactory> registry_factory(
1132       net::HttpAuthHandlerRegistryFactory::Create(
1133           supported_schemes, globals_->url_security_manager.get(),
1134           resolver, gssapi_library_name_, negotiate_disable_cname_lookup_,
1135           negotiate_enable_port_));
1136   return registry_factory.release();
1137 }
1138
1139 void IOThread::ClearHostCache() {
1140   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
1141
1142   net::HostCache* host_cache = globals_->host_resolver->GetHostCache();
1143   if (host_cache)
1144     host_cache->clear();
1145 }
1146
1147 void IOThread::InitializeNetworkSessionParams(
1148     net::HttpNetworkSession::Params* params) {
1149   InitializeNetworkSessionParamsFromGlobals(*globals_, params);
1150 }
1151
1152 // static
1153 void IOThread::InitializeNetworkSessionParamsFromGlobals(
1154     const IOThread::Globals& globals,
1155     net::HttpNetworkSession::Params* params) {
1156   params->host_resolver = globals.host_resolver.get();
1157   params->cert_verifier = globals.cert_verifier.get();
1158   params->cert_policy_enforcer = globals.cert_policy_enforcer.get();
1159   params->channel_id_service = globals.system_channel_id_service.get();
1160   params->transport_security_state = globals.transport_security_state.get();
1161   params->ssl_config_service = globals.ssl_config_service.get();
1162   params->http_auth_handler_factory = globals.http_auth_handler_factory.get();
1163   params->http_server_properties =
1164       globals.http_server_properties->GetWeakPtr();
1165   params->network_delegate = globals.system_network_delegate.get();
1166   params->host_mapping_rules = globals.host_mapping_rules.get();
1167   params->ignore_certificate_errors = globals.ignore_certificate_errors;
1168   params->use_stale_while_revalidate = globals.use_stale_while_revalidate;
1169   params->testing_fixed_http_port = globals.testing_fixed_http_port;
1170   params->testing_fixed_https_port = globals.testing_fixed_https_port;
1171   globals.enable_tcp_fast_open_for_ssl.CopyToIfSet(
1172       &params->enable_tcp_fast_open_for_ssl);
1173
1174   globals.initial_max_spdy_concurrent_streams.CopyToIfSet(
1175       &params->spdy_initial_max_concurrent_streams);
1176   globals.force_spdy_single_domain.CopyToIfSet(
1177       &params->force_spdy_single_domain);
1178   globals.enable_spdy_compression.CopyToIfSet(
1179       &params->enable_spdy_compression);
1180   globals.enable_spdy_ping_based_connection_checking.CopyToIfSet(
1181       &params->enable_spdy_ping_based_connection_checking);
1182   globals.spdy_default_protocol.CopyToIfSet(
1183       &params->spdy_default_protocol);
1184   params->next_protos = globals.next_protos;
1185   globals.trusted_spdy_proxy.CopyToIfSet(&params->trusted_spdy_proxy);
1186   globals.force_spdy_over_ssl.CopyToIfSet(&params->force_spdy_over_ssl);
1187   globals.force_spdy_always.CopyToIfSet(&params->force_spdy_always);
1188   params->forced_spdy_exclusions = globals.forced_spdy_exclusions;
1189   globals.use_alternate_protocols.CopyToIfSet(
1190       &params->use_alternate_protocols);
1191   globals.alternate_protocol_probability_threshold.CopyToIfSet(
1192       &params->alternate_protocol_probability_threshold);
1193
1194   globals.enable_quic.CopyToIfSet(&params->enable_quic);
1195   globals.enable_quic_for_proxies.CopyToIfSet(&params->enable_quic_for_proxies);
1196   globals.quic_always_require_handshake_confirmation.CopyToIfSet(
1197       &params->quic_always_require_handshake_confirmation);
1198   globals.quic_disable_connection_pooling.CopyToIfSet(
1199       &params->quic_disable_connection_pooling);
1200   globals.quic_load_server_info_timeout_srtt_multiplier.CopyToIfSet(
1201       &params->quic_load_server_info_timeout_srtt_multiplier);
1202   globals.quic_enable_connection_racing.CopyToIfSet(
1203       &params->quic_enable_connection_racing);
1204   globals.quic_enable_non_blocking_io.CopyToIfSet(
1205       &params->quic_enable_non_blocking_io);
1206   globals.quic_disable_disk_cache.CopyToIfSet(
1207       &params->quic_disable_disk_cache);
1208   globals.quic_max_number_of_lossy_connections.CopyToIfSet(
1209       &params->quic_max_number_of_lossy_connections);
1210   globals.quic_packet_loss_threshold.CopyToIfSet(
1211       &params->quic_packet_loss_threshold);
1212   globals.quic_socket_receive_buffer_size.CopyToIfSet(
1213       &params->quic_socket_receive_buffer_size);
1214   globals.enable_quic_port_selection.CopyToIfSet(
1215       &params->enable_quic_port_selection);
1216   globals.quic_max_packet_length.CopyToIfSet(&params->quic_max_packet_length);
1217   globals.quic_user_agent_id.CopyToIfSet(&params->quic_user_agent_id);
1218   globals.quic_supported_versions.CopyToIfSet(
1219       &params->quic_supported_versions);
1220   params->quic_connection_options = globals.quic_connection_options;
1221
1222   globals.origin_to_force_quic_on.CopyToIfSet(
1223       &params->origin_to_force_quic_on);
1224   params->enable_user_alternate_protocol_ports =
1225       globals.enable_user_alternate_protocol_ports;
1226 }
1227
1228 base::TimeTicks IOThread::creation_time() const {
1229   return creation_time_;
1230 }
1231
1232 net::SSLConfigService* IOThread::GetSSLConfigService() {
1233   return ssl_config_service_manager_->Get();
1234 }
1235
1236 void IOThread::ChangedToOnTheRecordOnIOThread() {
1237   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
1238
1239   // Clear the host cache to avoid showing entries from the OTR session
1240   // in about:net-internals.
1241   ClearHostCache();
1242 }
1243
1244 void IOThread::InitSystemRequestContext() {
1245   if (system_url_request_context_getter_.get())
1246     return;
1247   // If we're in unit_tests, IOThread may not be run.
1248   if (!BrowserThread::IsMessageLoopValid(BrowserThread::IO))
1249     return;
1250   system_proxy_config_service_.reset(
1251       ProxyServiceFactory::CreateProxyConfigService(
1252           pref_proxy_config_tracker_.get()));
1253   system_url_request_context_getter_ =
1254       new SystemURLRequestContextGetter(this);
1255   // Safe to post an unretained this pointer, since IOThread is
1256   // guaranteed to outlive the IO BrowserThread.
1257   BrowserThread::PostTask(
1258       BrowserThread::IO,
1259       FROM_HERE,
1260       base::Bind(&IOThread::InitSystemRequestContextOnIOThread,
1261                  base::Unretained(this)));
1262 }
1263
1264 void IOThread::InitSystemRequestContextOnIOThread() {
1265   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
1266   DCHECK(!globals_->system_proxy_service.get());
1267   DCHECK(system_proxy_config_service_.get());
1268
1269   const base::CommandLine& command_line =
1270       *base::CommandLine::ForCurrentProcess();
1271   globals_->system_proxy_service.reset(
1272       ProxyServiceFactory::CreateProxyService(
1273           net_log_,
1274           globals_->proxy_script_fetcher_context.get(),
1275           globals_->system_network_delegate.get(),
1276           system_proxy_config_service_.release(),
1277           command_line,
1278           quick_check_enabled_.GetValue()));
1279
1280   net::HttpNetworkSession::Params system_params;
1281   InitializeNetworkSessionParams(&system_params);
1282   system_params.net_log = net_log_;
1283   system_params.proxy_service = globals_->system_proxy_service.get();
1284
1285   globals_->system_http_transaction_factory.reset(
1286       new net::HttpNetworkLayer(
1287           new net::HttpNetworkSession(system_params)));
1288   globals_->system_url_request_job_factory.reset(
1289       new net::URLRequestJobFactoryImpl());
1290   globals_->system_request_context.reset(
1291       ConstructSystemRequestContext(globals_, net_log_));
1292   globals_->system_request_context->set_ssl_config_service(
1293       globals_->ssl_config_service.get());
1294   globals_->system_request_context->set_http_server_properties(
1295       globals_->http_server_properties->GetWeakPtr());
1296 }
1297
1298 void IOThread::UpdateDnsClientEnabled() {
1299   globals()->host_resolver->SetDnsClientEnabled(*dns_client_enabled_);
1300 }
1301
1302 void IOThread::ConfigureQuic(const base::CommandLine& command_line) {
1303   // Always fetch the field trial group to ensure it is reported correctly.
1304   // The command line flags will be associated with a group that is reported
1305   // so long as trial is actually queried.
1306   std::string group =
1307       base::FieldTrialList::FindFullName(kQuicFieldTrialName);
1308   VariationParameters params;
1309   if (!variations::GetVariationParams(kQuicFieldTrialName, &params)) {
1310     params.clear();
1311   }
1312
1313   ConfigureQuicGlobals(command_line, group, params, globals_);
1314 }
1315
1316 // static
1317 void IOThread::ConfigureQuicGlobals(
1318     const base::CommandLine& command_line,
1319     base::StringPiece quic_trial_group,
1320     const VariationParameters& quic_trial_params,
1321     IOThread::Globals* globals) {
1322   bool enable_quic = ShouldEnableQuic(command_line, quic_trial_group);
1323   globals->enable_quic.set(enable_quic);
1324   bool enable_quic_for_proxies = ShouldEnableQuicForProxies(command_line,
1325                                                             quic_trial_group);
1326   globals->enable_quic_for_proxies.set(enable_quic_for_proxies);
1327   if (enable_quic) {
1328     globals->quic_always_require_handshake_confirmation.set(
1329         ShouldQuicAlwaysRequireHandshakeConfirmation(quic_trial_params));
1330     globals->quic_disable_connection_pooling.set(
1331         ShouldQuicDisableConnectionPooling(quic_trial_params));
1332     int receive_buffer_size = GetQuicSocketReceiveBufferSize(quic_trial_params);
1333     if (receive_buffer_size != 0) {
1334       globals->quic_socket_receive_buffer_size.set(receive_buffer_size);
1335     }
1336     float load_server_info_timeout_srtt_multiplier =
1337         GetQuicLoadServerInfoTimeoutSrttMultiplier(quic_trial_params);
1338     if (load_server_info_timeout_srtt_multiplier != 0) {
1339       globals->quic_load_server_info_timeout_srtt_multiplier.set(
1340           load_server_info_timeout_srtt_multiplier);
1341     }
1342     globals->quic_enable_connection_racing.set(
1343         ShouldQuicEnableConnectionRacing(quic_trial_params));
1344     globals->quic_enable_non_blocking_io.set(
1345         ShouldQuicEnableNonBlockingIO(quic_trial_params));
1346     globals->quic_disable_disk_cache.set(
1347         ShouldQuicDisableDiskCache(quic_trial_params));
1348     int max_number_of_lossy_connections = GetQuicMaxNumberOfLossyConnections(
1349         quic_trial_params);
1350     if (max_number_of_lossy_connections != 0) {
1351       globals->quic_max_number_of_lossy_connections.set(
1352           max_number_of_lossy_connections);
1353     }
1354     float packet_loss_threshold = GetQuicPacketLossThreshold(quic_trial_params);
1355     if (packet_loss_threshold != 0)
1356       globals->quic_packet_loss_threshold.set(packet_loss_threshold);
1357     globals->enable_quic_port_selection.set(
1358         ShouldEnableQuicPortSelection(command_line));
1359     globals->quic_connection_options =
1360         GetQuicConnectionOptions(command_line, quic_trial_params);
1361     if (ShouldEnableQuicPacing(command_line, quic_trial_params)) {
1362       globals->quic_connection_options.push_back(net::kPACE);
1363     }
1364   }
1365
1366   size_t max_packet_length = GetQuicMaxPacketLength(command_line,
1367                                                     quic_trial_params);
1368   if (max_packet_length != 0) {
1369     globals->quic_max_packet_length.set(max_packet_length);
1370   }
1371
1372   std::string quic_user_agent_id =
1373       chrome::VersionInfo::GetVersionStringModifier();
1374   if (!quic_user_agent_id.empty())
1375     quic_user_agent_id.push_back(' ');
1376   chrome::VersionInfo version_info;
1377   quic_user_agent_id.append(version_info.ProductNameAndVersionForUserAgent());
1378   globals->quic_user_agent_id.set(quic_user_agent_id);
1379
1380   net::QuicVersion version = GetQuicVersion(command_line, quic_trial_params);
1381   if (version != net::QUIC_VERSION_UNSUPPORTED) {
1382     net::QuicVersionVector supported_versions;
1383     supported_versions.push_back(version);
1384     globals->quic_supported_versions.set(supported_versions);
1385   }
1386
1387   double threshold =
1388       GetAlternateProtocolProbabilityThreshold(command_line, quic_trial_params);
1389   if (threshold >=0 && threshold <= 1) {
1390     globals->alternate_protocol_probability_threshold.set(threshold);
1391     globals->http_server_properties->SetAlternateProtocolProbabilityThreshold(
1392         threshold);
1393   }
1394
1395   if (command_line.HasSwitch(switches::kOriginToForceQuicOn)) {
1396     net::HostPortPair quic_origin =
1397         net::HostPortPair::FromString(
1398             command_line.GetSwitchValueASCII(switches::kOriginToForceQuicOn));
1399     if (!quic_origin.IsEmpty()) {
1400       globals->origin_to_force_quic_on.set(quic_origin);
1401     }
1402   }
1403 }
1404
1405 bool IOThread::ShouldEnableQuic(const base::CommandLine& command_line,
1406                                 base::StringPiece quic_trial_group) {
1407   if (command_line.HasSwitch(switches::kDisableQuic))
1408     return false;
1409
1410   if (command_line.HasSwitch(switches::kEnableQuic))
1411     return true;
1412
1413   return quic_trial_group.starts_with(kQuicFieldTrialEnabledGroupName) ||
1414       quic_trial_group.starts_with(kQuicFieldTrialHttpsEnabledGroupName);
1415 }
1416
1417 // static
1418 bool IOThread::ShouldEnableQuicForProxies(const base::CommandLine& command_line,
1419                                           base::StringPiece quic_trial_group) {
1420   return ShouldEnableQuic(command_line, quic_trial_group) ||
1421       ShouldEnableQuicForDataReductionProxy();
1422 }
1423
1424 // static
1425 bool IOThread::ShouldEnableQuicForDataReductionProxy() {
1426   const base::CommandLine& command_line =
1427         *base::CommandLine::ForCurrentProcess();
1428
1429   if (command_line.HasSwitch(switches::kDisableQuic))
1430     return false;
1431
1432   return data_reduction_proxy::DataReductionProxyParams::
1433       IsIncludedInQuicFieldTrial();
1434 }
1435
1436 bool IOThread::ShouldEnableQuicPortSelection(
1437     const base::CommandLine& command_line) {
1438   if (command_line.HasSwitch(switches::kDisableQuicPortSelection))
1439     return false;
1440
1441   if (command_line.HasSwitch(switches::kEnableQuicPortSelection))
1442     return true;
1443
1444   return false;  // Default to disabling port selection on all channels.
1445 }
1446
1447 bool IOThread::ShouldEnableQuicPacing(
1448     const base::CommandLine& command_line,
1449     const VariationParameters& quic_trial_params) {
1450   if (command_line.HasSwitch(switches::kEnableQuicPacing))
1451     return true;
1452
1453   if (command_line.HasSwitch(switches::kDisableQuicPacing))
1454     return false;
1455
1456   return LowerCaseEqualsASCII(
1457       GetVariationParam(quic_trial_params, "enable_pacing"),
1458       "true");
1459 }
1460
1461 net::QuicTagVector IOThread::GetQuicConnectionOptions(
1462     const base::CommandLine& command_line,
1463     const VariationParameters& quic_trial_params) {
1464   if (command_line.HasSwitch(switches::kQuicConnectionOptions)) {
1465     return net::QuicUtils::ParseQuicConnectionOptions(
1466         command_line.GetSwitchValueASCII(switches::kQuicConnectionOptions));
1467   }
1468
1469   VariationParameters::const_iterator it =
1470       quic_trial_params.find("connection_options");
1471   if (it == quic_trial_params.end()) {
1472     return net::QuicTagVector();
1473   }
1474
1475   return net::QuicUtils::ParseQuicConnectionOptions(it->second);
1476 }
1477
1478 // static
1479 double IOThread::GetAlternateProtocolProbabilityThreshold(
1480     const base::CommandLine& command_line,
1481     const VariationParameters& quic_trial_params) {
1482   double value;
1483   if (command_line.HasSwitch(
1484           switches::kAlternateProtocolProbabilityThreshold)) {
1485     if (base::StringToDouble(
1486             command_line.GetSwitchValueASCII(
1487                 switches::kAlternateProtocolProbabilityThreshold),
1488             &value)) {
1489       return value;
1490     }
1491   }
1492   if (command_line.HasSwitch(switches::kEnableQuic)) {
1493     return 0;
1494   }
1495   if (base::StringToDouble(
1496           GetVariationParam(quic_trial_params,
1497                             "alternate_protocol_probability_threshold"),
1498           &value)) {
1499     return value;
1500   }
1501   return -1;
1502 }
1503
1504 // static
1505 bool IOThread::ShouldQuicAlwaysRequireHandshakeConfirmation(
1506     const VariationParameters& quic_trial_params) {
1507   return LowerCaseEqualsASCII(
1508       GetVariationParam(quic_trial_params,
1509                         "always_require_handshake_confirmation"),
1510       "true");
1511 }
1512
1513 // static
1514 bool IOThread::ShouldQuicDisableConnectionPooling(
1515     const VariationParameters& quic_trial_params) {
1516   return LowerCaseEqualsASCII(
1517       GetVariationParam(quic_trial_params, "disable_connection_pooling"),
1518       "true");
1519 }
1520
1521 // static
1522 float IOThread::GetQuicLoadServerInfoTimeoutSrttMultiplier(
1523     const VariationParameters& quic_trial_params) {
1524   double value;
1525   if (base::StringToDouble(GetVariationParam(quic_trial_params,
1526                                              "load_server_info_time_to_srtt"),
1527                            &value)) {
1528     return (float)value;
1529   }
1530   return 0.0f;
1531 }
1532
1533 // static
1534 bool IOThread::ShouldQuicEnableConnectionRacing(
1535     const VariationParameters& quic_trial_params) {
1536   return LowerCaseEqualsASCII(
1537       GetVariationParam(quic_trial_params, "enable_connection_racing"),
1538       "true");
1539 }
1540
1541 // static
1542 bool IOThread::ShouldQuicEnableNonBlockingIO(
1543     const VariationParameters& quic_trial_params) {
1544   return LowerCaseEqualsASCII(
1545       GetVariationParam(quic_trial_params, "enable_non_blocking_io"),
1546       "true");
1547 }
1548
1549 // static
1550 bool IOThread::ShouldQuicDisableDiskCache(
1551     const VariationParameters& quic_trial_params) {
1552   return LowerCaseEqualsASCII(
1553       GetVariationParam(quic_trial_params, "disable_disk_cache"), "true");
1554 }
1555
1556 // static
1557 int IOThread::GetQuicMaxNumberOfLossyConnections(
1558     const VariationParameters& quic_trial_params) {
1559   int value;
1560   if (base::StringToInt(GetVariationParam(quic_trial_params,
1561                                           "max_number_of_lossy_connections"),
1562                         &value)) {
1563     return value;
1564   }
1565   return 0;
1566 }
1567
1568 // static
1569 float IOThread::GetQuicPacketLossThreshold(
1570     const VariationParameters& quic_trial_params) {
1571   double value;
1572   if (base::StringToDouble(GetVariationParam(quic_trial_params,
1573                                              "packet_loss_threshold"),
1574                            &value)) {
1575     return (float)value;
1576   }
1577   return 0.0f;
1578 }
1579
1580 // static
1581 int IOThread::GetQuicSocketReceiveBufferSize(
1582     const VariationParameters& quic_trial_params) {
1583   int value;
1584   if (base::StringToInt(GetVariationParam(quic_trial_params,
1585                                           "receive_buffer_size"),
1586                         &value)) {
1587     return value;
1588   }
1589   return 0;
1590 }
1591
1592 // static
1593 size_t IOThread::GetQuicMaxPacketLength(
1594     const base::CommandLine& command_line,
1595     const VariationParameters& quic_trial_params) {
1596   if (command_line.HasSwitch(switches::kQuicMaxPacketLength)) {
1597     unsigned value;
1598     if (!base::StringToUint(
1599             command_line.GetSwitchValueASCII(switches::kQuicMaxPacketLength),
1600             &value)) {
1601       return 0;
1602     }
1603     return value;
1604   }
1605
1606   unsigned value;
1607   if (base::StringToUint(GetVariationParam(quic_trial_params,
1608                                            "max_packet_length"),
1609                          &value)) {
1610     return value;
1611   }
1612   return 0;
1613 }
1614
1615 // static
1616 net::QuicVersion IOThread::GetQuicVersion(
1617     const base::CommandLine& command_line,
1618     const VariationParameters& quic_trial_params) {
1619   if (command_line.HasSwitch(switches::kQuicVersion)) {
1620     return ParseQuicVersion(
1621         command_line.GetSwitchValueASCII(switches::kQuicVersion));
1622   }
1623
1624   return ParseQuicVersion(GetVariationParam(quic_trial_params, "quic_version"));
1625 }
1626
1627 // static
1628 net::QuicVersion IOThread::ParseQuicVersion(const std::string& quic_version) {
1629   net::QuicVersionVector supported_versions = net::QuicSupportedVersions();
1630   for (size_t i = 0; i < supported_versions.size(); ++i) {
1631     net::QuicVersion version = supported_versions[i];
1632     if (net::QuicVersionToString(version) == quic_version) {
1633       return version;
1634     }
1635   }
1636
1637   return net::QUIC_VERSION_UNSUPPORTED;
1638 }