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 "content/public/common/user_agent.h"
  50 #include "net/base/host_mapping_rules.h"
  51 #include "net/base/net_util.h"
  52 #include "net/base/network_quality_estimator.h"
  53 #include "net/base/sdch_manager.h"
  54 #include "net/cert/cert_policy_enforcer.h"
  55 #include "net/cert/cert_verifier.h"
  56 #include "net/cert/cert_verify_proc.h"
  57 #include "net/cert/ct_known_logs.h"
  58 #include "net/cert/ct_known_logs_static.h"
  59 #include "net/cert/ct_log_verifier.h"
  60 #include "net/cert/ct_verifier.h"
  61 #include "net/cert/multi_log_ct_verifier.h"
  62 #include "net/cert/multi_threaded_cert_verifier.h"
  63 #include "net/cookies/cookie_store.h"
  64 #include "net/dns/host_cache.h"
  65 #include "net/dns/host_resolver.h"
  66 #include "net/dns/mapped_host_resolver.h"
  67 #include "net/ftp/ftp_network_layer.h"
  68 #include "net/http/http_auth_filter.h"
  69 #include "net/http/http_auth_handler_factory.h"
  70 #include "net/http/http_network_layer.h"
  71 #include "net/http/http_server_properties_impl.h"
  72 #include "net/proxy/proxy_config_service.h"
  73 #include "net/proxy/proxy_script_fetcher_impl.h"
  74 #include "net/proxy/proxy_service.h"
  75 #include "net/quic/crypto/crypto_protocol.h"
  76 #include "net/quic/quic_protocol.h"
  77 #include "net/quic/quic_utils.h"
  78 #include "net/socket/tcp_client_socket.h"
  79 #include "net/spdy/spdy_session.h"
  80 #include "net/ssl/channel_id_service.h"
  81 #include "net/ssl/default_channel_id_store.h"
  82 #include "net/url_request/data_protocol_handler.h"
  83 #include "net/url_request/file_protocol_handler.h"
  84 #include "net/url_request/ftp_protocol_handler.h"
  85 #include "net/url_request/static_http_user_agent_settings.h"
  86 #include "net/url_request/url_fetcher.h"
  87 #include "net/url_request/url_request_backoff_manager.h"
  88 #include "net/url_request/url_request_context.h"
  89 #include "net/url_request/url_request_context_getter.h"
  90 #include "net/url_request/url_request_job_factory_impl.h"
  91 #include "url/url_constants.h"
  92
  93 #if defined(ENABLE_CONFIGURATION_POLICY)
  94 #include "policy/policy_constants.h"
  95 #endif
  96
  97 #if defined(ENABLE_EXTENSIONS)
  98 #include "chrome/browser/extensions/event_router_forwarder.h"
  99 #endif
 100
 101 #if defined(USE_NSS_CERTS) || defined(OS_IOS)
 102 #include "net/cert_net/nss_ocsp.h"
 103 #endif
 104
 105 #if defined(OS_ANDROID)
 106 #include "base/android/build_info.h"
 107 #endif
 108
 109 #if defined(OS_CHROMEOS)
 110 #include "chrome/browser/chromeos/net/cert_verify_proc_chromeos.h"
 111 #include "chromeos/network/host_resolver_impl_chromeos.h"
 112 #endif
 113
 114 using content::BrowserThread;
 115
 116 class SafeBrowsingURLRequestContext;
 117
 118 // The IOThread object must outlive any tasks posted to the IO thread before the
 119 // Quit task, so base::Bind() calls are not refcounted.
 120
 121 namespace {
 122
 123 const char kTCPFastOpenFieldTrialName[] = "TCPFastOpen";
 124 const char kTCPFastOpenHttpsEnabledGroupName[] = "HttpsEnabled";
 125
 126 const char kQuicFieldTrialName[] = "QUIC";
 127 const char kQuicFieldTrialEnabledGroupName[] = "Enabled";
 128 const char kQuicFieldTrialHttpsEnabledGroupName[] = "HttpsEnabled";
 129
 130 // The SPDY trial composes two different trial plus control groups:
 131 //  * A "holdback" group with SPDY disabled, and corresponding control
 132 //  (SPDY/3.1). The primary purpose of the holdback group is to encourage site
 133 //  operators to do feature detection rather than UA-sniffing. As such, this
 134 //  trial runs continuously.
 135 //  * A SPDY/4 experiment, for SPDY/4 (aka HTTP/2) vs SPDY/3.1 comparisons and
 136 //  eventual SPDY/4 deployment.
 137 const char kSpdyFieldTrialName[] = "SPDY";
 138 const char kSpdyFieldTrialHoldbackGroupNamePrefix[] = "SpdyDisabled";
 139 const char kSpdyFieldTrialSpdy31GroupNamePrefix[] = "Spdy31Enabled";
 140 const char kSpdyFieldTrialSpdy4GroupNamePrefix[] = "Spdy4Enabled";
 141 const char kSpdyFieldTrialParametrizedPrefix[] = "Parametrized";
 142
 143 // Field trial for network quality estimator. Seeds RTT and downstream
 144 // throughput observations with values that correspond to the connection type
 145 // determined by the operating system.
 146 const char kNetworkQualityEstimatorFieldTrialName[] = "NetworkQualityEstimator";
 147
 148 #if defined(OS_MACOSX) && !defined(OS_IOS)
 149 void ObserveKeychainEvents() {
 150   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 151   net::CertDatabase::GetInstance()->SetMessageLoopForKeychainEvents();
 152 }
 153 #endif
 154
 155 // Used for the "system" URLRequestContext.
 156 class SystemURLRequestContext : public net::URLRequestContext {
 157  public:
 158   SystemURLRequestContext() {
 159 #if defined(USE_NSS_CERTS) || defined(OS_IOS)
 160     net::SetURLRequestContextForNSSHttpIO(this);
 161 #endif
 162   }
 163
 164  private:
 165   ~SystemURLRequestContext() override {
 166     AssertNoURLRequests();
 167 #if defined(USE_NSS_CERTS) || defined(OS_IOS)
 168     net::SetURLRequestContextForNSSHttpIO(NULL);
 169 #endif
 170   }
 171 };
 172
 173 scoped_ptr<net::HostResolver> CreateGlobalHostResolver(net::NetLog* net_log) {
 174   TRACE_EVENT0("startup", "IOThread::CreateGlobalHostResolver");
 175   const base::CommandLine& command_line =
 176       *base::CommandLine::ForCurrentProcess();
 177
 178   net::HostResolver::Options options;
 179
 180   // Use the retry attempts override from the command-line, if any.
 181   if (command_line.HasSwitch(switches::kHostResolverRetryAttempts)) {
 182     std::string s =
 183         command_line.GetSwitchValueASCII(switches::kHostResolverRetryAttempts);
 184     // Parse the switch (it should be a non-negative integer).
 185     int n;
 186     if (base::StringToInt(s, &n) && n >= 0) {
 187       options.max_retry_attempts = static_cast<size_t>(n);
 188     } else {
 189       LOG(ERROR) << "Invalid switch for host resolver retry attempts: " << s;
 190     }
 191   }
 192
 193   scoped_ptr<net::HostResolver> global_host_resolver;
 194 #if defined OS_CHROMEOS
 195   global_host_resolver =
 196       chromeos::HostResolverImplChromeOS::CreateSystemResolver(options,
 197                                                                net_log);
 198 #else
 199   global_host_resolver =
 200       net::HostResolver::CreateSystemResolver(options, net_log);
 201 #endif
 202
 203   // If hostname remappings were specified on the command-line, layer these
 204   // rules on top of the real host resolver. This allows forwarding all requests
 205   // through a designated test server.
 206   if (!command_line.HasSwitch(switches::kHostResolverRules))
 207     return global_host_resolver.Pass();
 208
 209   scoped_ptr<net::MappedHostResolver> remapped_resolver(
 210       new net::MappedHostResolver(global_host_resolver.Pass()));
 211   remapped_resolver->SetRulesFromString(
 212       command_line.GetSwitchValueASCII(switches::kHostResolverRules));
 213   return remapped_resolver.Pass();
 214 }
 215
 216 // TODO(willchan): Remove proxy script fetcher context since it's not necessary
 217 // now that I got rid of refcounting URLRequestContexts.
 218 // See IOThread::Globals for details.
 219 net::URLRequestContext*
 220 ConstructProxyScriptFetcherContext(IOThread::Globals* globals,
 221                                    net::NetLog* net_log) {
 222   net::URLRequestContext* context = new net::URLRequestContext;
 223   context->set_net_log(net_log);
 224   context->set_host_resolver(globals->host_resolver.get());
 225   context->set_cert_verifier(globals->cert_verifier.get());
 226   context->set_transport_security_state(
 227       globals->transport_security_state.get());
 228   context->set_cert_transparency_verifier(
 229       globals->cert_transparency_verifier.get());
 230   context->set_http_auth_handler_factory(
 231       globals->http_auth_handler_factory.get());
 232   context->set_proxy_service(globals->proxy_script_fetcher_proxy_service.get());
 233   context->set_http_transaction_factory(
 234       globals->proxy_script_fetcher_http_transaction_factory.get());
 235   context->set_job_factory(
 236       globals->proxy_script_fetcher_url_request_job_factory.get());
 237   context->set_cookie_store(globals->system_cookie_store.get());
 238   context->set_channel_id_service(
 239       globals->system_channel_id_service.get());
 240   context->set_network_delegate(globals->system_network_delegate.get());
 241   context->set_http_user_agent_settings(
 242       globals->http_user_agent_settings.get());
 243   // TODO(rtenneti): We should probably use HttpServerPropertiesManager for the
 244   // system URLRequestContext too. There's no reason this should be tied to a
 245   // profile.
 246   return context;
 247 }
 248
 249 net::URLRequestContext*
 250 ConstructSystemRequestContext(IOThread::Globals* globals,
 251                               net::NetLog* net_log) {
 252   net::URLRequestContext* context = new SystemURLRequestContext;
 253   context->set_net_log(net_log);
 254   context->set_host_resolver(globals->host_resolver.get());
 255   context->set_cert_verifier(globals->cert_verifier.get());
 256   context->set_transport_security_state(
 257       globals->transport_security_state.get());
 258   context->set_cert_transparency_verifier(
 259       globals->cert_transparency_verifier.get());
 260   context->set_http_auth_handler_factory(
 261       globals->http_auth_handler_factory.get());
 262   context->set_proxy_service(globals->system_proxy_service.get());
 263   context->set_http_transaction_factory(
 264       globals->system_http_transaction_factory.get());
 265   context->set_job_factory(globals->system_url_request_job_factory.get());
 266   context->set_cookie_store(globals->system_cookie_store.get());
 267   context->set_channel_id_service(
 268       globals->system_channel_id_service.get());
 269   context->set_network_delegate(globals->system_network_delegate.get());
 270   context->set_http_user_agent_settings(
 271       globals->http_user_agent_settings.get());
 272   context->set_network_quality_estimator(
 273       globals->network_quality_estimator.get());
 274   context->set_backoff_manager(globals->url_request_backoff_manager.get());
 275   return context;
 276 }
 277
 278 int GetSwitchValueAsInt(const base::CommandLine& command_line,
 279                         const std::string& switch_name) {
 280   int value;
 281   if (!base::StringToInt(command_line.GetSwitchValueASCII(switch_name),
 282                          &value)) {
 283     return 0;
 284   }
 285   return value;
 286 }
 287
 288 // Returns the value associated with |key| in |params| or "" if the
 289 // key is not present in the map.
 290 const std::string& GetVariationParam(
 291     const std::map<std::string, std::string>& params,
 292     const std::string& key) {
 293   std::map<std::string, std::string>::const_iterator it = params.find(key);
 294   if (it == params.end())
 295     return base::EmptyString();
 296
 297   return it->second;
 298 }
 299
 300 // Parse kUseSpdy command line flag options, which may contain the following:
 301 //
 302 //   "off"                      : Disables SPDY support entirely.
 303 //   "no-ping"                  : Disables SPDY ping connection testing.
 304 //   "exclude=<host>"           : Disables SPDY support for the host <host>.
 305 //   "no-compress"              : Disables SPDY header compression.
 306 //   "no-alt-protocols          : Disables alternate protocol support.
 307 //   "init-max-streams=<limit>" : Specifies the maximum number of concurrent
 308 //                                streams for a SPDY session, unless the
 309 //                                specifies a different value via SETTINGS.
 310 void ConfigureSpdyGlobalsFromUseSpdyArgument(const std::string& mode,
 311                                              IOThread::Globals* globals) {
 312   static const char kOff[] = "off";
 313   static const char kDisablePing[] = "no-ping";
 314   static const char kExclude[] = "exclude";  // Hosts to exclude
 315   static const char kDisableCompression[] = "no-compress";
 316   static const char kDisableAltProtocols[] = "no-alt-protocols";
 317   static const char kInitialMaxConcurrentStreams[] = "init-max-streams";
 318
 319   for (const base::StringPiece& element : base::SplitStringPiece(
 320            mode, ",", base::TRIM_WHITESPACE, base::SPLIT_WANT_ALL)) {
 321     std::vector<base::StringPiece> name_value = base::SplitStringPiece(
 322         element, "=", base::TRIM_WHITESPACE, base::SPLIT_WANT_ALL);
 323     const base::StringPiece option =
 324         name_value.size() > 0 ? name_value[0] : base::StringPiece();
 325     const base::StringPiece value =
 326         name_value.size() > 1 ? name_value[1] : base::StringPiece();
 327
 328     if (option == kOff) {
 329       net::HttpStreamFactory::set_spdy_enabled(false);
 330       continue;
 331     }
 332     if (option == kDisablePing) {
 333       globals->enable_spdy_ping_based_connection_checking.set(false);
 334       continue;
 335     }
 336     if (option == kExclude) {
 337       globals->forced_spdy_exclusions.insert(
 338           net::HostPortPair::FromURL(GURL(value.as_string())));
 339       continue;
 340     }
 341     if (option == kDisableCompression) {
 342       globals->enable_spdy_compression.set(false);
 343       continue;
 344     }
 345     if (option == kDisableAltProtocols) {
 346       globals->use_alternate_protocols.set(false);
 347       continue;
 348     }
 349     if (option == kInitialMaxConcurrentStreams) {
 350       int streams;
 351       if (base::StringToInt(value, &streams)) {
 352         globals->initial_max_spdy_concurrent_streams.set(streams);
 353         continue;
 354       }
 355     }
 356     LOG(DFATAL) << "Unrecognized spdy option: " << option.as_string();
 357   }
 358 }
 359
 360 }  // namespace
 361
 362 class IOThread::LoggingNetworkChangeObserver
 363     : public net::NetworkChangeNotifier::IPAddressObserver,
 364       public net::NetworkChangeNotifier::ConnectionTypeObserver,
 365       public net::NetworkChangeNotifier::NetworkChangeObserver {
 366  public:
 367   // |net_log| must remain valid throughout our lifetime.
 368   explicit LoggingNetworkChangeObserver(net::NetLog* net_log)
 369       : net_log_(net_log) {
 370     net::NetworkChangeNotifier::AddIPAddressObserver(this);
 371     net::NetworkChangeNotifier::AddConnectionTypeObserver(this);
 372     net::NetworkChangeNotifier::AddNetworkChangeObserver(this);
 373   }
 374
 375   ~LoggingNetworkChangeObserver() override {
 376     net::NetworkChangeNotifier::RemoveIPAddressObserver(this);
 377     net::NetworkChangeNotifier::RemoveConnectionTypeObserver(this);
 378     net::NetworkChangeNotifier::RemoveNetworkChangeObserver(this);
 379   }
 380
 381   // NetworkChangeNotifier::IPAddressObserver implementation.
 382   void OnIPAddressChanged() override {
 383     VLOG(1) << "Observed a change to the network IP addresses";
 384
 385     net_log_->AddGlobalEntry(net::NetLog::TYPE_NETWORK_IP_ADDRESSES_CHANGED);
 386   }
 387
 388   // NetworkChangeNotifier::ConnectionTypeObserver implementation.
 389   void OnConnectionTypeChanged(
 390       net::NetworkChangeNotifier::ConnectionType type) override {
 391     std::string type_as_string =
 392         net::NetworkChangeNotifier::ConnectionTypeToString(type);
 393
 394     VLOG(1) << "Observed a change to network connectivity state "
 395             << type_as_string;
 396
 397     net_log_->AddGlobalEntry(
 398         net::NetLog::TYPE_NETWORK_CONNECTIVITY_CHANGED,
 399         net::NetLog::StringCallback("new_connection_type", &type_as_string));
 400   }
 401
 402   // NetworkChangeNotifier::NetworkChangeObserver implementation.
 403   void OnNetworkChanged(
 404       net::NetworkChangeNotifier::ConnectionType type) override {
 405     std::string type_as_string =
 406         net::NetworkChangeNotifier::ConnectionTypeToString(type);
 407
 408     VLOG(1) << "Observed a network change to state " << type_as_string;
 409
 410     net_log_->AddGlobalEntry(
 411         net::NetLog::TYPE_NETWORK_CHANGED,
 412         net::NetLog::StringCallback("new_connection_type", &type_as_string));
 413   }
 414
 415  private:
 416   net::NetLog* net_log_;
 417   DISALLOW_COPY_AND_ASSIGN(LoggingNetworkChangeObserver);
 418 };
 419
 420 class SystemURLRequestContextGetter : public net::URLRequestContextGetter {
 421  public:
 422   explicit SystemURLRequestContextGetter(IOThread* io_thread);
 423
 424   // Implementation for net::UrlRequestContextGetter.
 425   net::URLRequestContext* GetURLRequestContext() override;
 426   scoped_refptr<base::SingleThreadTaskRunner> GetNetworkTaskRunner()
 427       const override;
 428
 429  protected:
 430   ~SystemURLRequestContextGetter() override;
 431
 432  private:
 433   IOThread* const io_thread_;  // Weak pointer, owned by BrowserProcess.
 434   scoped_refptr<base::SingleThreadTaskRunner> network_task_runner_;
 435
 436   base::debug::LeakTracker<SystemURLRequestContextGetter> leak_tracker_;
 437 };
 438
 439 SystemURLRequestContextGetter::SystemURLRequestContextGetter(
 440     IOThread* io_thread)
 441     : io_thread_(io_thread),
 442       network_task_runner_(
 443           BrowserThread::GetMessageLoopProxyForThread(BrowserThread::IO)) {
 444 }
 445
 446 SystemURLRequestContextGetter::~SystemURLRequestContextGetter() {}
 447
 448 net::URLRequestContext* SystemURLRequestContextGetter::GetURLRequestContext() {
 449   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 450   DCHECK(io_thread_->globals()->system_request_context.get());
 451
 452   return io_thread_->globals()->system_request_context.get();
 453 }
 454
 455 scoped_refptr<base::SingleThreadTaskRunner>
 456 SystemURLRequestContextGetter::GetNetworkTaskRunner() const {
 457   return network_task_runner_;
 458 }
 459
 460 IOThread::Globals::
 461 SystemRequestContextLeakChecker::SystemRequestContextLeakChecker(
 462     Globals* globals)
 463     : globals_(globals) {
 464   DCHECK(globals_);
 465 }
 466
 467 IOThread::Globals::
 468 SystemRequestContextLeakChecker::~SystemRequestContextLeakChecker() {
 469   if (globals_->system_request_context.get())
 470     globals_->system_request_context->AssertNoURLRequests();
 471 }
 472
 473 IOThread::Globals::Globals()
 474     : system_request_context_leak_checker(this),
 475       ignore_certificate_errors(false),
 476       testing_fixed_http_port(0),
 477       testing_fixed_https_port(0),
 478       enable_user_alternate_protocol_ports(false) {
 479 }
 480
 481 IOThread::Globals::~Globals() {}
 482
 483 // |local_state| is passed in explicitly in order to (1) reduce implicit
 484 // dependencies and (2) make IOThread more flexible for testing.
 485 IOThread::IOThread(
 486     PrefService* local_state,
 487     policy::PolicyService* policy_service,
 488     ChromeNetLog* net_log,
 489     extensions::EventRouterForwarder* extension_event_router_forwarder)
 490     : net_log_(net_log),
 491 #if defined(ENABLE_EXTENSIONS)
 492       extension_event_router_forwarder_(extension_event_router_forwarder),
 493 #endif
 494       globals_(NULL),
 495       is_spdy_disabled_by_policy_(false),
 496       is_quic_allowed_by_policy_(true),
 497       creation_time_(base::TimeTicks::Now()),
 498       weak_factory_(this) {
 499   auth_schemes_ = local_state->GetString(prefs::kAuthSchemes);
 500   negotiate_disable_cname_lookup_ = local_state->GetBoolean(
 501       prefs::kDisableAuthNegotiateCnameLookup);
 502   negotiate_enable_port_ = local_state->GetBoolean(
 503       prefs::kEnableAuthNegotiatePort);
 504   auth_server_whitelist_ = local_state->GetString(prefs::kAuthServerWhitelist);
 505   auth_delegate_whitelist_ = local_state->GetString(
 506       prefs::kAuthNegotiateDelegateWhitelist);
 507   gssapi_library_name_ = local_state->GetString(prefs::kGSSAPILibraryName);
 508   auth_android_negotiate_account_type_ =
 509       local_state->GetString(prefs::kAuthAndroidNegotiateAccountType);
 510   pref_proxy_config_tracker_.reset(
 511       ProxyServiceFactory::CreatePrefProxyConfigTrackerOfLocalState(
 512           local_state));
 513   ChromeNetworkDelegate::InitializePrefsOnUIThread(
 514       &system_enable_referrers_,
 515       NULL,
 516       NULL,
 517       NULL,
 518       local_state);
 519   ssl_config_service_manager_.reset(
 520       SSLConfigServiceManager::CreateDefaultManager(local_state));
 521
 522   base::Value* dns_client_enabled_default = new base::FundamentalValue(
 523       chrome_browser_net::ConfigureAsyncDnsFieldTrial());
 524   local_state->SetDefaultPrefValue(prefs::kBuiltInDnsClientEnabled,
 525                                    dns_client_enabled_default);
 526   chrome_browser_net::LogAsyncDnsPrefSource(
 527       local_state->FindPreference(prefs::kBuiltInDnsClientEnabled));
 528
 529   dns_client_enabled_.Init(prefs::kBuiltInDnsClientEnabled,
 530                            local_state,
 531                            base::Bind(&IOThread::UpdateDnsClientEnabled,
 532                                       base::Unretained(this)));
 533   dns_client_enabled_.MoveToThread(
 534       BrowserThread::GetMessageLoopProxyForThread(BrowserThread::IO));
 535
 536   quick_check_enabled_.Init(prefs::kQuickCheckEnabled,
 537                             local_state);
 538   quick_check_enabled_.MoveToThread(
 539       BrowserThread::GetMessageLoopProxyForThread(BrowserThread::IO));
 540
 541 #if defined(ENABLE_CONFIGURATION_POLICY)
 542   is_spdy_disabled_by_policy_ = policy_service->GetPolicies(
 543       policy::PolicyNamespace(policy::POLICY_DOMAIN_CHROME, std::string())).Get(
 544           policy::key::kDisableSpdy) != NULL;
 545
 546   const base::Value* value = policy_service->GetPolicies(
 547       policy::PolicyNamespace(policy::POLICY_DOMAIN_CHROME,
 548       std::string())).GetValue(policy::key::kQuicAllowed);
 549   if (value)
 550     value->GetAsBoolean(&is_quic_allowed_by_policy_);
 551 #endif  // ENABLE_CONFIGURATION_POLICY
 552
 553   BrowserThread::SetDelegate(BrowserThread::IO, this);
 554 }
 555
 556 IOThread::~IOThread() {
 557   // This isn't needed for production code, but in tests, IOThread may
 558   // be multiply constructed.
 559   BrowserThread::SetDelegate(BrowserThread::IO, NULL);
 560
 561   pref_proxy_config_tracker_->DetachFromPrefService();
 562   DCHECK(!globals_);
 563 }
 564
 565 IOThread::Globals* IOThread::globals() {
 566   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 567   return globals_;
 568 }
 569
 570 void IOThread::SetGlobalsForTesting(Globals* globals) {
 571   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 572   DCHECK(!globals || !globals_);
 573   globals_ = globals;
 574 }
 575
 576 ChromeNetLog* IOThread::net_log() {
 577   return net_log_;
 578 }
 579
 580 void IOThread::ChangedToOnTheRecord() {
 581   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 582   BrowserThread::PostTask(
 583       BrowserThread::IO,
 584       FROM_HERE,
 585       base::Bind(&IOThread::ChangedToOnTheRecordOnIOThread,
 586                  base::Unretained(this)));
 587 }
 588
 589 net::URLRequestContextGetter* IOThread::system_url_request_context_getter() {
 590   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 591   if (!system_url_request_context_getter_.get()) {
 592     InitSystemRequestContext();
 593   }
 594   return system_url_request_context_getter_.get();
 595 }
 596
 597 void IOThread::Init() {
 598   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 599   // is fixed.
 600   tracked_objects::ScopedTracker tracking_profile1(
 601       FROM_HERE_WITH_EXPLICIT_FUNCTION("466432 IOThread::InitAsync::Start"));
 602   TRACE_EVENT0("startup", "IOThread::InitAsync");
 603   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 604
 605 #if defined(USE_NSS_CERTS) || defined(OS_IOS)
 606   net::SetMessageLoopForNSSHttpIO();
 607 #endif
 608
 609   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 610   // is fixed.
 611   tracked_objects::ScopedTracker tracking_profile2(
 612       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 613           "466432 IOThread::InitAsync::CommandLineForCurrentProcess"));
 614   const base::CommandLine& command_line =
 615       *base::CommandLine::ForCurrentProcess();
 616
 617   DCHECK(!globals_);
 618   globals_ = new Globals;
 619
 620   // Add an observer that will emit network change events to the ChromeNetLog.
 621   // Assuming NetworkChangeNotifier dispatches in FIFO order, we should be
 622   // logging the network change before other IO thread consumers respond to it.
 623   network_change_observer_.reset(
 624       new LoggingNetworkChangeObserver(net_log_));
 625
 626   // Setup the HistogramWatcher to run on the IO thread.
 627   net::NetworkChangeNotifier::InitHistogramWatcher();
 628
 629 #if defined(ENABLE_EXTENSIONS)
 630   globals_->extension_event_router_forwarder =
 631       extension_event_router_forwarder_;
 632 #endif
 633
 634   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 635   // is fixed.
 636   tracked_objects::ScopedTracker tracking_profile3(
 637       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 638           "466432 IOThread::InitAsync::ChromeNetworkDelegate"));
 639   scoped_ptr<ChromeNetworkDelegate> chrome_network_delegate(
 640       new ChromeNetworkDelegate(extension_event_router_forwarder(),
 641                                 &system_enable_referrers_));
 642
 643   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 644   // is fixed.
 645   tracked_objects::ScopedTracker tracking_profile4(
 646       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 647           "466432 IOThread::InitAsync::CreateGlobalHostResolver"));
 648   globals_->system_network_delegate = chrome_network_delegate.Pass();
 649   globals_->host_resolver = CreateGlobalHostResolver(net_log_);
 650
 651   std::map<std::string, std::string> network_quality_estimator_params;
 652   variations::GetVariationParams(kNetworkQualityEstimatorFieldTrialName,
 653                                  &network_quality_estimator_params);
 654   globals_->network_quality_estimator.reset(
 655       new net::NetworkQualityEstimator(network_quality_estimator_params));
 656
 657   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 658   // is fixed.
 659   tracked_objects::ScopedTracker tracking_profile5(
 660       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 661           "466432 IOThread::InitAsync::UpdateDnsClientEnabled::Start"));
 662   UpdateDnsClientEnabled();
 663   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 664   // is fixed.
 665   tracked_objects::ScopedTracker tracking_profile6(
 666       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 667           "466432 IOThread::InitAsync::UpdateDnsClientEnabled::End"));
 668 #if defined(OS_CHROMEOS)
 669   // Creates a CertVerifyProc that doesn't allow any profile-provided certs.
 670   globals_->cert_verifier.reset(new net::MultiThreadedCertVerifier(
 671       new chromeos::CertVerifyProcChromeOS()));
 672 #else
 673   globals_->cert_verifier.reset(new net::MultiThreadedCertVerifier(
 674       net::CertVerifyProc::CreateDefault()));
 675 #endif
 676
 677   globals_->transport_security_state.reset(new net::TransportSecurityState());
 678
 679   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 680   // is fixed.
 681   tracked_objects::ScopedTracker tracking_profile8(
 682       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 683           "466432 IOThread::InitAsync::CreateLogVerifiers::Start"));
 684   std::vector<scoped_refptr<net::CTLogVerifier>> ct_logs(
 685       net::ct::CreateLogVerifiersForKnownLogs());
 686
 687   // Add logs from command line
 688   if (command_line.HasSwitch(switches::kCertificateTransparencyLog)) {
 689     std::string switch_value = command_line.GetSwitchValueASCII(
 690         switches::kCertificateTransparencyLog);
 691     for (const base::StringPiece& curr_log : base::SplitStringPiece(
 692              switch_value, ",", base::TRIM_WHITESPACE, base::SPLIT_WANT_ALL)) {
 693       std::vector<std::string> log_metadata = base::SplitString(
 694           curr_log, ":", base::TRIM_WHITESPACE, base::SPLIT_WANT_ALL);
 695       CHECK_GE(log_metadata.size(), 3u)
 696           << "CT log metadata missing: Switch format is "
 697           << "'description:base64_key:url_without_schema'.";
 698       std::string log_description(log_metadata[0]);
 699       std::string log_url(std::string("https://") + log_metadata[2]);
 700       std::string ct_public_key_data;
 701       CHECK(base::Base64Decode(log_metadata[1], &ct_public_key_data))
 702           << "Unable to decode CT public key.";
 703       scoped_refptr<net::CTLogVerifier> external_log_verifier(
 704           net::CTLogVerifier::Create(ct_public_key_data, log_description,
 705                                      log_url));
 706       CHECK(external_log_verifier) << "Unable to parse CT public key.";
 707       VLOG(1) << "Adding log with description " << log_description;
 708       ct_logs.push_back(external_log_verifier);
 709     }
 710   }
 711
 712   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 713   // is fixed.
 714   tracked_objects::ScopedTracker tracking_profile9(
 715       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 716           "466432 IOThread::InitAsync::CreateLogVerifiers::End"));
 717   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 718   // is fixed.
 719   tracked_objects::ScopedTracker tracking_profile7(
 720       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 721           "466432 IOThread::InitAsync::CreateMultiLogVerifier"));
 722   net::MultiLogCTVerifier* ct_verifier = new net::MultiLogCTVerifier();
 723   globals_->cert_transparency_verifier.reset(ct_verifier);
 724   // Add built-in logs
 725   ct_verifier->AddLogs(ct_logs);
 726
 727   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 728   // is fixed.
 729   tracked_objects::ScopedTracker tracking_profile10(
 730       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 731           "466432 IOThread::InitAsync::CertPolicyEnforcer"));
 732   net::CertPolicyEnforcer* policy_enforcer = new net::CertPolicyEnforcer;
 733   globals_->cert_policy_enforcer.reset(policy_enforcer);
 734
 735   globals_->ssl_config_service = GetSSLConfigService();
 736
 737   globals_->http_auth_handler_factory.reset(CreateDefaultAuthHandlerFactory(
 738       globals_->host_resolver.get()));
 739   globals_->http_server_properties.reset(new net::HttpServerPropertiesImpl());
 740   // For the ProxyScriptFetcher, we use a direct ProxyService.
 741   globals_->proxy_script_fetcher_proxy_service.reset(
 742       net::ProxyService::CreateDirectWithNetLog(net_log_));
 743   // In-memory cookie store.
 744   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 745   // is fixed.
 746   tracked_objects::ScopedTracker tracking_profile11(
 747       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 748           "466432 IOThread::InitAsync::CreateCookieStore::Start"));
 749   globals_->system_cookie_store =
 750         content::CreateCookieStore(content::CookieStoreConfig());
 751   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 752   // is fixed.
 753   tracked_objects::ScopedTracker tracking_profile12(
 754       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 755           "466432 IOThread::InitAsync::CreateCookieStore::End"));
 756   // In-memory channel ID store.
 757   globals_->system_channel_id_service.reset(
 758       new net::ChannelIDService(
 759           new net::DefaultChannelIDStore(NULL),
 760           base::WorkerPool::GetTaskRunner(true)));
 761   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 762   // is fixed.
 763   tracked_objects::ScopedTracker tracking_profile12_1(
 764       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 765           "466432 IOThread::InitAsync::CreateDnsProbeService"));
 766   globals_->dns_probe_service.reset(new chrome_browser_net::DnsProbeService());
 767   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 768   // is fixed.
 769   tracked_objects::ScopedTracker tracking_profile12_2(
 770       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 771           "466432 IOThread::InitAsync::CreateHostMappingRules"));
 772   globals_->host_mapping_rules.reset(new net::HostMappingRules());
 773   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 774   // is fixed.
 775   tracked_objects::ScopedTracker tracking_profile12_3(
 776       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 777           "466432 IOThread::InitAsync::CreateHTTPUserAgentSettings"));
 778   globals_->http_user_agent_settings.reset(
 779       new net::StaticHttpUserAgentSettings(std::string(), GetUserAgent()));
 780   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 781   // is fixed.
 782   tracked_objects::ScopedTracker tracking_profile12_4(
 783       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 784           "466432 IOThread::InitAsync::CommandLineConfiguration"));
 785   if (command_line.HasSwitch(switches::kHostRules)) {
 786     TRACE_EVENT_BEGIN0("startup", "IOThread::InitAsync:SetRulesFromString");
 787     globals_->host_mapping_rules->SetRulesFromString(
 788         command_line.GetSwitchValueASCII(switches::kHostRules));
 789     TRACE_EVENT_END0("startup", "IOThread::InitAsync:SetRulesFromString");
 790   }
 791   if (command_line.HasSwitch(switches::kIgnoreCertificateErrors))
 792     globals_->ignore_certificate_errors = true;
 793   if (command_line.HasSwitch(switches::kTestingFixedHttpPort)) {
 794     globals_->testing_fixed_http_port =
 795         GetSwitchValueAsInt(command_line, switches::kTestingFixedHttpPort);
 796   }
 797   if (command_line.HasSwitch(switches::kTestingFixedHttpsPort)) {
 798     globals_->testing_fixed_https_port =
 799         GetSwitchValueAsInt(command_line, switches::kTestingFixedHttpsPort);
 800   }
 801   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 802   // is fixed.
 803   tracked_objects::ScopedTracker tracking_profile12_5(
 804       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 805           "466432 IOThread::InitAsync::QuicConfiguration"));
 806   ConfigureQuic(command_line);
 807   if (command_line.HasSwitch(
 808           switches::kEnableUserAlternateProtocolPorts)) {
 809     globals_->enable_user_alternate_protocol_ports = true;
 810   }
 811   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 812   // is fixed.
 813   tracked_objects::ScopedTracker tracking_profile13(
 814       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 815           "466432 IOThread::InitAsync::InitializeNetworkOptions"));
 816   InitializeNetworkOptions(command_line);
 817
 818   net::HttpNetworkSession::Params session_params;
 819   InitializeNetworkSessionParams(&session_params);
 820   session_params.net_log = net_log_;
 821   session_params.proxy_service =
 822       globals_->proxy_script_fetcher_proxy_service.get();
 823
 824   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 825   // is fixed.
 826   tracked_objects::ScopedTracker tracking_profile14(
 827       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 828           "466432 IOThread::InitAsync::HttpNetorkSession::Start"));
 829   TRACE_EVENT_BEGIN0("startup", "IOThread::InitAsync:HttpNetworkSession");
 830   scoped_refptr<net::HttpNetworkSession> network_session(
 831       new net::HttpNetworkSession(session_params));
 832   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 833   // is fixed.
 834   tracked_objects::ScopedTracker tracking_profile15(
 835       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 836           "466432 IOThread::InitAsync::HttpNetorkSession::End"));
 837   globals_->proxy_script_fetcher_http_transaction_factory
 838       .reset(new net::HttpNetworkLayer(network_session.get()));
 839   TRACE_EVENT_END0("startup", "IOThread::InitAsync:HttpNetworkSession");
 840   scoped_ptr<net::URLRequestJobFactoryImpl> job_factory(
 841       new net::URLRequestJobFactoryImpl());
 842
 843   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 844   // is fixed.
 845   tracked_objects::ScopedTracker tracking_profile16(
 846       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 847           "466432 IOThread::InitAsync::SetProtocolHandler"));
 848   job_factory->SetProtocolHandler(url::kDataScheme,
 849                                   new net::DataProtocolHandler());
 850   job_factory->SetProtocolHandler(
 851       url::kFileScheme,
 852       new net::FileProtocolHandler(
 853           content::BrowserThread::GetBlockingPool()->
 854               GetTaskRunnerWithShutdownBehavior(
 855                   base::SequencedWorkerPool::SKIP_ON_SHUTDOWN)));
 856 #if !defined(DISABLE_FTP_SUPPORT)
 857   globals_->proxy_script_fetcher_ftp_transaction_factory.reset(
 858       new net::FtpNetworkLayer(globals_->host_resolver.get()));
 859   job_factory->SetProtocolHandler(
 860       url::kFtpScheme,
 861       new net::FtpProtocolHandler(
 862           globals_->proxy_script_fetcher_ftp_transaction_factory.get()));
 863 #endif
 864   globals_->proxy_script_fetcher_url_request_job_factory = job_factory.Pass();
 865
 866   globals_->proxy_script_fetcher_context.reset(
 867       ConstructProxyScriptFetcherContext(globals_, net_log_));
 868
 869   const version_info::Channel channel = chrome::VersionInfo::GetChannel();
 870   if (channel == version_info::Channel::UNKNOWN ||
 871       channel == version_info::Channel::CANARY ||
 872       channel == version_info::Channel::DEV) {
 873     globals_->url_request_backoff_manager.reset(
 874         new net::URLRequestBackoffManager());
 875   }
 876
 877 #if defined(OS_MACOSX) && !defined(OS_IOS)
 878   // Start observing Keychain events. This needs to be done on the UI thread,
 879   // as Keychain services requires a CFRunLoop.
 880   BrowserThread::PostTask(BrowserThread::UI,
 881                           FROM_HERE,
 882                           base::Bind(&ObserveKeychainEvents));
 883 #endif
 884
 885   // InitSystemRequestContext turns right around and posts a task back
 886   // to the IO thread, so we can't let it run until we know the IO
 887   // thread has started.
 888   //
 889   // Note that since we are at BrowserThread::Init time, the UI thread
 890   // is blocked waiting for the thread to start.  Therefore, posting
 891   // this task to the main thread's message loop here is guaranteed to
 892   // get it onto the message loop while the IOThread object still
 893   // exists.  However, the message might not be processed on the UI
 894   // thread until after IOThread is gone, so use a weak pointer.
 895   BrowserThread::PostTask(BrowserThread::UI,
 896                           FROM_HERE,
 897                           base::Bind(&IOThread::InitSystemRequestContext,
 898                                      weak_factory_.GetWeakPtr()));
 899 }
 900
 901 void IOThread::CleanUp() {
 902   base::debug::LeakTracker<SafeBrowsingURLRequestContext>::CheckForLeaks();
 903
 904 #if defined(USE_NSS_CERTS) || defined(OS_IOS)
 905   net::ShutdownNSSHttpIO();
 906 #endif
 907
 908   system_url_request_context_getter_ = NULL;
 909
 910   // Release objects that the net::URLRequestContext could have been pointing
 911   // to.
 912
 913   // Shutdown the HistogramWatcher on the IO thread.
 914   net::NetworkChangeNotifier::ShutdownHistogramWatcher();
 915
 916   // This must be reset before the ChromeNetLog is destroyed.
 917   network_change_observer_.reset();
 918
 919   system_proxy_config_service_.reset();
 920
 921   delete globals_;
 922   globals_ = NULL;
 923
 924   base::debug::LeakTracker<SystemURLRequestContextGetter>::CheckForLeaks();
 925 }
 926
 927 void IOThread::InitializeNetworkOptions(const base::CommandLine& command_line) {
 928   // Only handle use-spdy command line flags if "spdy.disabled" preference is
 929   // not disabled via policy.
 930   if (is_spdy_disabled_by_policy_) {
 931     base::FieldTrial* trial = base::FieldTrialList::Find(kSpdyFieldTrialName);
 932     if (trial)
 933       trial->Disable();
 934   } else {
 935     std::string group = base::FieldTrialList::FindFullName(kSpdyFieldTrialName);
 936     VariationParameters params;
 937     if (!variations::GetVariationParams(kSpdyFieldTrialName, &params)) {
 938       params.clear();
 939     }
 940     ConfigureSpdyGlobals(command_line, group, params, globals_);
 941   }
 942
 943   ConfigureTCPFastOpen(command_line);
 944
 945   // TODO(rch): Make the client socket factory a per-network session
 946   // instance, constructed from a NetworkSession::Params, to allow us
 947   // to move this option to IOThread::Globals &
 948   // HttpNetworkSession::Params.
 949 }
 950
 951 void IOThread::ConfigureTCPFastOpen(const base::CommandLine& command_line) {
 952   const std::string trial_group =
 953       base::FieldTrialList::FindFullName(kTCPFastOpenFieldTrialName);
 954   if (trial_group == kTCPFastOpenHttpsEnabledGroupName)
 955     globals_->enable_tcp_fast_open_for_ssl.set(true);
 956   bool always_enable_if_supported =
 957       command_line.HasSwitch(switches::kEnableTcpFastOpen);
 958   // Check for OS support of TCP FastOpen, and turn it on for all connections
 959   // if indicated by user.
 960   net::CheckSupportAndMaybeEnableTCPFastOpen(always_enable_if_supported);
 961 }
 962
 963 // static
 964 void IOThread::ConfigureSpdyGlobals(
 965     const base::CommandLine& command_line,
 966     base::StringPiece spdy_trial_group,
 967     const VariationParameters& spdy_trial_params,
 968     IOThread::Globals* globals) {
 969   if (command_line.HasSwitch(switches::kTrustedSpdyProxy)) {
 970     globals->trusted_spdy_proxy.set(
 971         command_line.GetSwitchValueASCII(switches::kTrustedSpdyProxy));
 972   }
 973   if (command_line.HasSwitch(switches::kIgnoreUrlFetcherCertRequests))
 974     net::URLFetcher::SetIgnoreCertificateRequests(true);
 975
 976   if (command_line.HasSwitch(switches::kUseSpdy)) {
 977     std::string spdy_mode =
 978         command_line.GetSwitchValueASCII(switches::kUseSpdy);
 979     ConfigureSpdyGlobalsFromUseSpdyArgument(spdy_mode, globals);
 980     return;
 981   }
 982
 983   globals->next_protos.clear();
 984   globals->next_protos.push_back(net::kProtoHTTP11);
 985   bool enable_quic = false;
 986   globals->enable_quic.CopyToIfSet(&enable_quic);
 987   if (enable_quic) {
 988     globals->next_protos.push_back(net::kProtoQUIC1SPDY3);
 989   }
 990
 991   // No SPDY command-line flags have been specified. Examine trial groups.
 992   if (spdy_trial_group.starts_with(kSpdyFieldTrialHoldbackGroupNamePrefix)) {
 993     net::HttpStreamFactory::set_spdy_enabled(false);
 994     return;
 995   }
 996   if (spdy_trial_group.starts_with(kSpdyFieldTrialSpdy31GroupNamePrefix)) {
 997     globals->next_protos.push_back(net::kProtoSPDY31);
 998     globals->use_alternate_protocols.set(true);
 999     return;
1000   }
1001   if (spdy_trial_group.starts_with(kSpdyFieldTrialSpdy4GroupNamePrefix)) {
1002     globals->next_protos.push_back(net::kProtoSPDY31);
1003     globals->next_protos.push_back(net::kProtoHTTP2_14);
1004     globals->next_protos.push_back(net::kProtoHTTP2);
1005     globals->use_alternate_protocols.set(true);
1006     return;
1007   }
1008   if (spdy_trial_group.starts_with(kSpdyFieldTrialParametrizedPrefix)) {
1009     bool spdy_enabled = false;
1010     if (base::LowerCaseEqualsASCII(
1011             GetVariationParam(spdy_trial_params, "enable_spdy31"), "true")) {
1012       globals->next_protos.push_back(net::kProtoSPDY31);
1013       spdy_enabled = true;
1014     }
1015     if (base::LowerCaseEqualsASCII(
1016             GetVariationParam(spdy_trial_params, "enable_http2_14"), "true")) {
1017       globals->next_protos.push_back(net::kProtoHTTP2_14);
1018       spdy_enabled = true;
1019     }
1020     if (base::LowerCaseEqualsASCII(
1021             GetVariationParam(spdy_trial_params, "enable_http2"), "true")) {
1022       globals->next_protos.push_back(net::kProtoHTTP2);
1023       spdy_enabled = true;
1024     }
1025     // TODO(bnc): HttpStreamFactory::spdy_enabled_ is redundant with
1026     // globals->next_protos, can it be eliminated?
1027     net::HttpStreamFactory::set_spdy_enabled(spdy_enabled);
1028     globals->use_alternate_protocols.set(true);
1029     return;
1030   }
1031
1032   // By default, enable HTTP/2.
1033   globals->next_protos.push_back(net::kProtoSPDY31);
1034   globals->next_protos.push_back(net::kProtoHTTP2_14);
1035   globals->next_protos.push_back(net::kProtoHTTP2);
1036   globals->use_alternate_protocols.set(true);
1037 }
1038
1039 // static
1040 void IOThread::RegisterPrefs(PrefRegistrySimple* registry) {
1041   registry->RegisterStringPref(prefs::kAuthSchemes,
1042                                "basic,digest,ntlm,negotiate");
1043   registry->RegisterBooleanPref(prefs::kDisableAuthNegotiateCnameLookup, false);
1044   registry->RegisterBooleanPref(prefs::kEnableAuthNegotiatePort, false);
1045   registry->RegisterStringPref(prefs::kAuthServerWhitelist, std::string());
1046   registry->RegisterStringPref(prefs::kAuthNegotiateDelegateWhitelist,
1047                                std::string());
1048   registry->RegisterStringPref(prefs::kGSSAPILibraryName, std::string());
1049   registry->RegisterStringPref(prefs::kAuthAndroidNegotiateAccountType,
1050                                std::string());
1051   registry->RegisterStringPref(
1052       data_reduction_proxy::prefs::kDataReductionProxy, std::string());
1053   registry->RegisterBooleanPref(prefs::kEnableReferrers, true);
1054   data_reduction_proxy::RegisterPrefs(registry);
1055   registry->RegisterBooleanPref(prefs::kBuiltInDnsClientEnabled, true);
1056   registry->RegisterBooleanPref(prefs::kQuickCheckEnabled, true);
1057 }
1058
1059 net::HttpAuthHandlerFactory* IOThread::CreateDefaultAuthHandlerFactory(
1060     net::HostResolver* resolver) {
1061   net::HttpAuthFilterWhitelist* auth_filter_default_credentials = NULL;
1062   if (!auth_server_whitelist_.empty()) {
1063     auth_filter_default_credentials =
1064         new net::HttpAuthFilterWhitelist(auth_server_whitelist_);
1065   }
1066   net::HttpAuthFilterWhitelist* auth_filter_delegate = NULL;
1067   if (!auth_delegate_whitelist_.empty()) {
1068     auth_filter_delegate =
1069         new net::HttpAuthFilterWhitelist(auth_delegate_whitelist_);
1070   }
1071   globals_->url_security_manager.reset(
1072       net::URLSecurityManager::Create(auth_filter_default_credentials,
1073                                       auth_filter_delegate));
1074   std::vector<std::string> supported_schemes;
1075   base::SplitString(auth_schemes_, ',', &supported_schemes);
1076
1077   scoped_ptr<net::HttpAuthHandlerRegistryFactory> registry_factory(
1078       net::HttpAuthHandlerRegistryFactory::Create(
1079           supported_schemes, globals_->url_security_manager.get(), resolver,
1080           gssapi_library_name_, auth_android_negotiate_account_type_,
1081           negotiate_disable_cname_lookup_, negotiate_enable_port_));
1082   return registry_factory.release();
1083 }
1084
1085 void IOThread::ClearHostCache() {
1086   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
1087
1088   net::HostCache* host_cache = globals_->host_resolver->GetHostCache();
1089   if (host_cache)
1090     host_cache->clear();
1091 }
1092
1093 void IOThread::InitializeNetworkSessionParams(
1094     net::HttpNetworkSession::Params* params) {
1095   InitializeNetworkSessionParamsFromGlobals(*globals_, params);
1096 }
1097
1098 // static
1099 void IOThread::InitializeNetworkSessionParamsFromGlobals(
1100     const IOThread::Globals& globals,
1101     net::HttpNetworkSession::Params* params) {
1102   params->host_resolver = globals.host_resolver.get();
1103   params->cert_verifier = globals.cert_verifier.get();
1104   params->cert_policy_enforcer = globals.cert_policy_enforcer.get();
1105   params->channel_id_service = globals.system_channel_id_service.get();
1106   params->transport_security_state = globals.transport_security_state.get();
1107   params->ssl_config_service = globals.ssl_config_service.get();
1108   params->http_auth_handler_factory = globals.http_auth_handler_factory.get();
1109   params->http_server_properties =
1110       globals.http_server_properties->GetWeakPtr();
1111   params->network_delegate = globals.system_network_delegate.get();
1112   params->host_mapping_rules = globals.host_mapping_rules.get();
1113   params->ignore_certificate_errors = globals.ignore_certificate_errors;
1114   params->testing_fixed_http_port = globals.testing_fixed_http_port;
1115   params->testing_fixed_https_port = globals.testing_fixed_https_port;
1116   globals.enable_tcp_fast_open_for_ssl.CopyToIfSet(
1117       &params->enable_tcp_fast_open_for_ssl);
1118
1119   globals.initial_max_spdy_concurrent_streams.CopyToIfSet(
1120       &params->spdy_initial_max_concurrent_streams);
1121   globals.enable_spdy_compression.CopyToIfSet(
1122       &params->enable_spdy_compression);
1123   globals.enable_spdy_ping_based_connection_checking.CopyToIfSet(
1124       &params->enable_spdy_ping_based_connection_checking);
1125   globals.spdy_default_protocol.CopyToIfSet(
1126       &params->spdy_default_protocol);
1127   params->next_protos = globals.next_protos;
1128   globals.trusted_spdy_proxy.CopyToIfSet(&params->trusted_spdy_proxy);
1129   params->forced_spdy_exclusions = globals.forced_spdy_exclusions;
1130   globals.use_alternate_protocols.CopyToIfSet(
1131       &params->use_alternate_protocols);
1132   globals.alternative_service_probability_threshold.CopyToIfSet(
1133       &params->alternative_service_probability_threshold);
1134
1135   globals.enable_quic.CopyToIfSet(&params->enable_quic);
1136   globals.enable_insecure_quic.CopyToIfSet(&params->enable_insecure_quic);
1137   globals.enable_quic_for_proxies.CopyToIfSet(&params->enable_quic_for_proxies);
1138   globals.quic_always_require_handshake_confirmation.CopyToIfSet(
1139       &params->quic_always_require_handshake_confirmation);
1140   globals.quic_disable_connection_pooling.CopyToIfSet(
1141       &params->quic_disable_connection_pooling);
1142   globals.quic_load_server_info_timeout_srtt_multiplier.CopyToIfSet(
1143       &params->quic_load_server_info_timeout_srtt_multiplier);
1144   globals.quic_enable_connection_racing.CopyToIfSet(
1145       &params->quic_enable_connection_racing);
1146   globals.quic_enable_non_blocking_io.CopyToIfSet(
1147       &params->quic_enable_non_blocking_io);
1148   globals.quic_prefer_aes.CopyToIfSet(&params->quic_prefer_aes);
1149   globals.quic_disable_disk_cache.CopyToIfSet(
1150       &params->quic_disable_disk_cache);
1151   globals.quic_max_number_of_lossy_connections.CopyToIfSet(
1152       &params->quic_max_number_of_lossy_connections);
1153   globals.quic_packet_loss_threshold.CopyToIfSet(
1154       &params->quic_packet_loss_threshold);
1155   globals.quic_socket_receive_buffer_size.CopyToIfSet(
1156       &params->quic_socket_receive_buffer_size);
1157   globals.enable_quic_port_selection.CopyToIfSet(
1158       &params->enable_quic_port_selection);
1159   globals.quic_max_packet_length.CopyToIfSet(&params->quic_max_packet_length);
1160   globals.quic_user_agent_id.CopyToIfSet(&params->quic_user_agent_id);
1161   globals.quic_supported_versions.CopyToIfSet(
1162       &params->quic_supported_versions);
1163   params->quic_connection_options = globals.quic_connection_options;
1164
1165   globals.origin_to_force_quic_on.CopyToIfSet(
1166       &params->origin_to_force_quic_on);
1167   params->enable_user_alternate_protocol_ports =
1168       globals.enable_user_alternate_protocol_ports;
1169 }
1170
1171 base::TimeTicks IOThread::creation_time() const {
1172   return creation_time_;
1173 }
1174
1175 net::SSLConfigService* IOThread::GetSSLConfigService() {
1176   return ssl_config_service_manager_->Get();
1177 }
1178
1179 void IOThread::ChangedToOnTheRecordOnIOThread() {
1180   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
1181
1182   // Clear the host cache to avoid showing entries from the OTR session
1183   // in about:net-internals.
1184   ClearHostCache();
1185 }
1186
1187 void IOThread::InitSystemRequestContext() {
1188   if (system_url_request_context_getter_.get())
1189     return;
1190   // If we're in unit_tests, IOThread may not be run.
1191   if (!BrowserThread::IsMessageLoopValid(BrowserThread::IO))
1192     return;
1193   system_proxy_config_service_.reset(
1194       ProxyServiceFactory::CreateProxyConfigService(
1195           pref_proxy_config_tracker_.get()));
1196   system_url_request_context_getter_ =
1197       new SystemURLRequestContextGetter(this);
1198   // Safe to post an unretained this pointer, since IOThread is
1199   // guaranteed to outlive the IO BrowserThread.
1200   BrowserThread::PostTask(
1201       BrowserThread::IO,
1202       FROM_HERE,
1203       base::Bind(&IOThread::InitSystemRequestContextOnIOThread,
1204                  base::Unretained(this)));
1205 }
1206
1207 void IOThread::InitSystemRequestContextOnIOThread() {
1208   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
1209   DCHECK(!globals_->system_proxy_service.get());
1210   DCHECK(system_proxy_config_service_.get());
1211
1212   const base::CommandLine& command_line =
1213       *base::CommandLine::ForCurrentProcess();
1214   globals_->system_proxy_service.reset(
1215       ProxyServiceFactory::CreateProxyService(
1216           net_log_,
1217           globals_->proxy_script_fetcher_context.get(),
1218           globals_->system_network_delegate.get(),
1219           system_proxy_config_service_.release(),
1220           command_line,
1221           quick_check_enabled_.GetValue()));
1222
1223   net::HttpNetworkSession::Params system_params;
1224   InitializeNetworkSessionParams(&system_params);
1225   system_params.net_log = net_log_;
1226   system_params.proxy_service = globals_->system_proxy_service.get();
1227
1228   globals_->system_http_transaction_factory.reset(
1229       new net::HttpNetworkLayer(
1230           new net::HttpNetworkSession(system_params)));
1231   globals_->system_url_request_job_factory.reset(
1232       new net::URLRequestJobFactoryImpl());
1233   globals_->system_request_context.reset(
1234       ConstructSystemRequestContext(globals_, net_log_));
1235   globals_->system_request_context->set_ssl_config_service(
1236       globals_->ssl_config_service.get());
1237   globals_->system_request_context->set_http_server_properties(
1238       globals_->http_server_properties->GetWeakPtr());
1239 }
1240
1241 void IOThread::UpdateDnsClientEnabled() {
1242   globals()->host_resolver->SetDnsClientEnabled(*dns_client_enabled_);
1243 }
1244
1245 void IOThread::ConfigureQuic(const base::CommandLine& command_line) {
1246   // Always fetch the field trial group to ensure it is reported correctly.
1247   // The command line flags will be associated with a group that is reported
1248   // so long as trial is actually queried.
1249   std::string group =
1250       base::FieldTrialList::FindFullName(kQuicFieldTrialName);
1251   VariationParameters params;
1252   if (!variations::GetVariationParams(kQuicFieldTrialName, &params)) {
1253     params.clear();
1254   }
1255
1256   ConfigureQuicGlobals(command_line, group, params, is_quic_allowed_by_policy_,
1257                        globals_);
1258 }
1259
1260 // static
1261 void IOThread::ConfigureQuicGlobals(
1262     const base::CommandLine& command_line,
1263     base::StringPiece quic_trial_group,
1264     const VariationParameters& quic_trial_params,
1265     bool quic_allowed_by_policy,
1266     IOThread::Globals* globals) {
1267   bool enable_quic = ShouldEnableQuic(command_line, quic_trial_group,
1268                                       quic_allowed_by_policy);
1269   globals->enable_quic.set(enable_quic);
1270   bool enable_quic_for_proxies = ShouldEnableQuicForProxies(
1271       command_line, quic_trial_group, quic_allowed_by_policy);
1272   globals->enable_quic_for_proxies.set(enable_quic_for_proxies);
1273   if (enable_quic) {
1274     globals->enable_insecure_quic.set(
1275         ShouldEnableInsecureQuic(command_line, quic_trial_params));
1276     globals->quic_always_require_handshake_confirmation.set(
1277         ShouldQuicAlwaysRequireHandshakeConfirmation(quic_trial_params));
1278     globals->quic_disable_connection_pooling.set(
1279         ShouldQuicDisableConnectionPooling(quic_trial_params));
1280     int receive_buffer_size = GetQuicSocketReceiveBufferSize(quic_trial_params);
1281     if (receive_buffer_size != 0) {
1282       globals->quic_socket_receive_buffer_size.set(receive_buffer_size);
1283     }
1284     float load_server_info_timeout_srtt_multiplier =
1285         GetQuicLoadServerInfoTimeoutSrttMultiplier(quic_trial_params);
1286     if (load_server_info_timeout_srtt_multiplier != 0) {
1287       globals->quic_load_server_info_timeout_srtt_multiplier.set(
1288           load_server_info_timeout_srtt_multiplier);
1289     }
1290     globals->quic_enable_connection_racing.set(
1291         ShouldQuicEnableConnectionRacing(quic_trial_params));
1292     globals->quic_enable_non_blocking_io.set(
1293         ShouldQuicEnableNonBlockingIO(quic_trial_params));
1294     globals->quic_disable_disk_cache.set(
1295         ShouldQuicDisableDiskCache(quic_trial_params));
1296     globals->quic_prefer_aes.set(
1297         ShouldQuicPreferAes(quic_trial_params));
1298     int max_number_of_lossy_connections = GetQuicMaxNumberOfLossyConnections(
1299         quic_trial_params);
1300     if (max_number_of_lossy_connections != 0) {
1301       globals->quic_max_number_of_lossy_connections.set(
1302           max_number_of_lossy_connections);
1303     }
1304     float packet_loss_threshold = GetQuicPacketLossThreshold(quic_trial_params);
1305     if (packet_loss_threshold != 0)
1306       globals->quic_packet_loss_threshold.set(packet_loss_threshold);
1307     globals->enable_quic_port_selection.set(
1308         ShouldEnableQuicPortSelection(command_line));
1309     globals->quic_connection_options =
1310         GetQuicConnectionOptions(command_line, quic_trial_params);
1311   }
1312
1313   size_t max_packet_length = GetQuicMaxPacketLength(command_line,
1314                                                     quic_trial_params);
1315   if (max_packet_length != 0) {
1316     globals->quic_max_packet_length.set(max_packet_length);
1317   }
1318
1319   std::string quic_user_agent_id =
1320       chrome::VersionInfo::GetVersionStringModifier();
1321   if (!quic_user_agent_id.empty())
1322     quic_user_agent_id.push_back(' ');
1323   chrome::VersionInfo version_info;
1324   quic_user_agent_id.append(version_info.ProductNameAndVersionForUserAgent());
1325   quic_user_agent_id.push_back(' ');
1326   quic_user_agent_id.append(content::BuildOSCpuInfo());
1327   globals->quic_user_agent_id.set(quic_user_agent_id);
1328
1329   net::QuicVersion version = GetQuicVersion(command_line, quic_trial_params);
1330   if (version != net::QUIC_VERSION_UNSUPPORTED) {
1331     net::QuicVersionVector supported_versions;
1332     supported_versions.push_back(version);
1333     globals->quic_supported_versions.set(supported_versions);
1334   }
1335
1336   double threshold = GetAlternativeProtocolProbabilityThreshold(
1337       command_line, quic_trial_params);
1338   if (threshold >=0 && threshold <= 1) {
1339     globals->alternative_service_probability_threshold.set(threshold);
1340     globals->http_server_properties->SetAlternativeServiceProbabilityThreshold(
1341         threshold);
1342   }
1343
1344   if (command_line.HasSwitch(switches::kOriginToForceQuicOn)) {
1345     net::HostPortPair quic_origin =
1346         net::HostPortPair::FromString(
1347             command_line.GetSwitchValueASCII(switches::kOriginToForceQuicOn));
1348     if (!quic_origin.IsEmpty()) {
1349       globals->origin_to_force_quic_on.set(quic_origin);
1350     }
1351   }
1352 }
1353
1354 bool IOThread::ShouldEnableQuic(const base::CommandLine& command_line,
1355                                 base::StringPiece quic_trial_group,
1356                                 bool quic_allowed_by_policy) {
1357   if (command_line.HasSwitch(switches::kDisableQuic) || !quic_allowed_by_policy)
1358     return false;
1359
1360   if (command_line.HasSwitch(switches::kEnableQuic))
1361     return true;
1362
1363   return quic_trial_group.starts_with(kQuicFieldTrialEnabledGroupName) ||
1364       quic_trial_group.starts_with(kQuicFieldTrialHttpsEnabledGroupName);
1365 }
1366
1367 // static
1368 bool IOThread::ShouldEnableQuicForProxies(const base::CommandLine& command_line,
1369                                           base::StringPiece quic_trial_group,
1370                                           bool quic_allowed_by_policy) {
1371   return ShouldEnableQuic(
1372       command_line, quic_trial_group, quic_allowed_by_policy) ||
1373       ShouldEnableQuicForDataReductionProxy();
1374 }
1375
1376 // static
1377 bool IOThread::ShouldEnableQuicForDataReductionProxy() {
1378   const base::CommandLine& command_line =
1379         *base::CommandLine::ForCurrentProcess();
1380
1381   if (command_line.HasSwitch(switches::kDisableQuic))
1382     return false;
1383
1384   return data_reduction_proxy::params::IsIncludedInQuicFieldTrial();
1385 }
1386
1387 // static
1388 bool IOThread::ShouldEnableInsecureQuic(
1389     const base::CommandLine& command_line,
1390     const VariationParameters& quic_trial_params) {
1391   if (command_line.HasSwitch(switches::kEnableInsecureQuic))
1392     return true;
1393
1394   return base::LowerCaseEqualsASCII(
1395       GetVariationParam(quic_trial_params, "enable_insecure_quic"),
1396       "true");
1397 }
1398
1399 bool IOThread::ShouldEnableQuicPortSelection(
1400     const base::CommandLine& command_line) {
1401   if (command_line.HasSwitch(switches::kDisableQuicPortSelection))
1402     return false;
1403
1404   if (command_line.HasSwitch(switches::kEnableQuicPortSelection))
1405     return true;
1406
1407   return false;  // Default to disabling port selection on all channels.
1408 }
1409
1410 net::QuicTagVector IOThread::GetQuicConnectionOptions(
1411     const base::CommandLine& command_line,
1412     const VariationParameters& quic_trial_params) {
1413   if (command_line.HasSwitch(switches::kQuicConnectionOptions)) {
1414     return net::QuicUtils::ParseQuicConnectionOptions(
1415         command_line.GetSwitchValueASCII(switches::kQuicConnectionOptions));
1416   }
1417
1418   VariationParameters::const_iterator it =
1419       quic_trial_params.find("connection_options");
1420   if (it == quic_trial_params.end()) {
1421     return net::QuicTagVector();
1422   }
1423
1424   return net::QuicUtils::ParseQuicConnectionOptions(it->second);
1425 }
1426
1427 // static
1428 double IOThread::GetAlternativeProtocolProbabilityThreshold(
1429     const base::CommandLine& command_line,
1430     const VariationParameters& quic_trial_params) {
1431   double value;
1432   if (command_line.HasSwitch(
1433           switches::kAlternativeServiceProbabilityThreshold)) {
1434     if (base::StringToDouble(
1435             command_line.GetSwitchValueASCII(
1436                 switches::kAlternativeServiceProbabilityThreshold),
1437             &value)) {
1438       return value;
1439     }
1440   }
1441   if (command_line.HasSwitch(switches::kEnableQuic)) {
1442     return 0;
1443   }
1444   // TODO(bnc): Remove when new parameter name rolls out and server
1445   // configuration is changed.
1446   if (base::StringToDouble(
1447           GetVariationParam(quic_trial_params,
1448                             "alternate_protocol_probability_threshold"),
1449           &value)) {
1450     return value;
1451   }
1452   if (base::StringToDouble(
1453           GetVariationParam(quic_trial_params,
1454                             "alternative_service_probability_threshold"),
1455           &value)) {
1456     return value;
1457   }
1458   return -1;
1459 }
1460
1461 // static
1462 bool IOThread::ShouldQuicAlwaysRequireHandshakeConfirmation(
1463     const VariationParameters& quic_trial_params) {
1464   return base::LowerCaseEqualsASCII(
1465       GetVariationParam(quic_trial_params,
1466                         "always_require_handshake_confirmation"),
1467       "true");
1468 }
1469
1470 // static
1471 bool IOThread::ShouldQuicDisableConnectionPooling(
1472     const VariationParameters& quic_trial_params) {
1473   return base::LowerCaseEqualsASCII(
1474       GetVariationParam(quic_trial_params, "disable_connection_pooling"),
1475       "true");
1476 }
1477
1478 // static
1479 float IOThread::GetQuicLoadServerInfoTimeoutSrttMultiplier(
1480     const VariationParameters& quic_trial_params) {
1481   double value;
1482   if (base::StringToDouble(GetVariationParam(quic_trial_params,
1483                                              "load_server_info_time_to_srtt"),
1484                            &value)) {
1485     return (float)value;
1486   }
1487   return 0.0f;
1488 }
1489
1490 // static
1491 bool IOThread::ShouldQuicEnableConnectionRacing(
1492     const VariationParameters& quic_trial_params) {
1493   return base::LowerCaseEqualsASCII(
1494       GetVariationParam(quic_trial_params, "enable_connection_racing"),
1495       "true");
1496 }
1497
1498 // static
1499 bool IOThread::ShouldQuicEnableNonBlockingIO(
1500     const VariationParameters& quic_trial_params) {
1501   return base::LowerCaseEqualsASCII(
1502       GetVariationParam(quic_trial_params, "enable_non_blocking_io"),
1503       "true");
1504 }
1505
1506 // static
1507 bool IOThread::ShouldQuicDisableDiskCache(
1508     const VariationParameters& quic_trial_params) {
1509   return base::LowerCaseEqualsASCII(
1510       GetVariationParam(quic_trial_params, "disable_disk_cache"), "true");
1511 }
1512
1513 // static
1514 bool IOThread::ShouldQuicPreferAes(
1515     const VariationParameters& quic_trial_params) {
1516   return base::LowerCaseEqualsASCII(
1517       GetVariationParam(quic_trial_params, "prefer_aes"), "true");
1518 }
1519
1520 // static
1521 int IOThread::GetQuicMaxNumberOfLossyConnections(
1522     const VariationParameters& quic_trial_params) {
1523   int value;
1524   if (base::StringToInt(GetVariationParam(quic_trial_params,
1525                                           "max_number_of_lossy_connections"),
1526                         &value)) {
1527     return value;
1528   }
1529   return 0;
1530 }
1531
1532 // static
1533 float IOThread::GetQuicPacketLossThreshold(
1534     const VariationParameters& quic_trial_params) {
1535   double value;
1536   if (base::StringToDouble(GetVariationParam(quic_trial_params,
1537                                              "packet_loss_threshold"),
1538                            &value)) {
1539     return (float)value;
1540   }
1541   return 0.0f;
1542 }
1543
1544 // static
1545 int IOThread::GetQuicSocketReceiveBufferSize(
1546     const VariationParameters& quic_trial_params) {
1547   int value;
1548   if (base::StringToInt(GetVariationParam(quic_trial_params,
1549                                           "receive_buffer_size"),
1550                         &value)) {
1551     return value;
1552   }
1553   return 0;
1554 }
1555
1556 // static
1557 size_t IOThread::GetQuicMaxPacketLength(
1558     const base::CommandLine& command_line,
1559     const VariationParameters& quic_trial_params) {
1560   if (command_line.HasSwitch(switches::kQuicMaxPacketLength)) {
1561     unsigned value;
1562     if (!base::StringToUint(
1563             command_line.GetSwitchValueASCII(switches::kQuicMaxPacketLength),
1564             &value)) {
1565       return 0;
1566     }
1567     return value;
1568   }
1569
1570   unsigned value;
1571   if (base::StringToUint(GetVariationParam(quic_trial_params,
1572                                            "max_packet_length"),
1573                          &value)) {
1574     return value;
1575   }
1576   return 0;
1577 }
1578
1579 // static
1580 net::QuicVersion IOThread::GetQuicVersion(
1581     const base::CommandLine& command_line,
1582     const VariationParameters& quic_trial_params) {
1583   if (command_line.HasSwitch(switches::kQuicVersion)) {
1584     return ParseQuicVersion(
1585         command_line.GetSwitchValueASCII(switches::kQuicVersion));
1586   }
1587
1588   return ParseQuicVersion(GetVariationParam(quic_trial_params, "quic_version"));
1589 }
1590
1591 // static
1592 net::QuicVersion IOThread::ParseQuicVersion(const std::string& quic_version) {
1593   net::QuicVersionVector supported_versions = net::QuicSupportedVersions();
1594   for (size_t i = 0; i < supported_versions.size(); ++i) {
1595     net::QuicVersion version = supported_versions[i];
1596     if (net::QuicVersionToString(version) == quic_version) {
1597       return version;
1598     }
1599   }
1600
1601   return net::QUIC_VERSION_UNSUPPORTED;
1602 }