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_network_delegate.h"
  34 #include "chrome/browser/net/connect_interceptor.h"
  35 #include "chrome/browser/net/dns_probe_service.h"
  36 #include "chrome/browser/net/proxy_service_factory.h"
  37 #include "chrome/common/channel_info.h"
  38 #include "chrome/common/chrome_content_client.h"
  39 #include "chrome/common/chrome_switches.h"
  40 #include "chrome/common/pref_names.h"
  41 #include "components/data_reduction_proxy/core/browser/data_reduction_proxy_prefs.h"
  42 #include "components/data_reduction_proxy/core/common/data_reduction_proxy_params.h"
  43 #include "components/net_log/chrome_net_log.h"
  44 #include "components/policy/core/common/policy_service.h"
  45 #include "components/proxy_config/pref_proxy_config_tracker.h"
  46 #include "components/variations/variations_associated_data.h"
  47 #include "components/version_info/version_info.h"
  48 #include "content/public/browser/browser_thread.h"
  49 #include "content/public/browser/cookie_store_factory.h"
  50 #include "content/public/common/user_agent.h"
  51 #include "net/base/external_estimate_provider.h"
  52 #include "net/base/host_mapping_rules.h"
  53 #include "net/base/net_util.h"
  54 #include "net/base/network_quality_estimator.h"
  55 #include "net/base/sdch_manager.h"
  56 #include "net/cert/cert_policy_enforcer.h"
  57 #include "net/cert/cert_verifier.h"
  58 #include "net/cert/cert_verify_proc.h"
  59 #include "net/cert/ct_known_logs.h"
  60 #include "net/cert/ct_known_logs_static.h"
  61 #include "net/cert/ct_log_verifier.h"
  62 #include "net/cert/ct_verifier.h"
  63 #include "net/cert/multi_log_ct_verifier.h"
  64 #include "net/cert/multi_threaded_cert_verifier.h"
  65 #include "net/cookies/cookie_store.h"
  66 #include "net/dns/host_cache.h"
  67 #include "net/dns/host_resolver.h"
  68 #include "net/dns/mapped_host_resolver.h"
  69 #include "net/ftp/ftp_network_layer.h"
  70 #include "net/http/http_auth_filter.h"
  71 #include "net/http/http_auth_handler_factory.h"
  72 #include "net/http/http_network_layer.h"
  73 #include "net/http/http_server_properties_impl.h"
  74 #include "net/proxy/proxy_config_service.h"
  75 #include "net/proxy/proxy_script_fetcher_impl.h"
  76 #include "net/proxy/proxy_service.h"
  77 #include "net/quic/crypto/crypto_protocol.h"
  78 #include "net/quic/quic_protocol.h"
  79 #include "net/quic/quic_utils.h"
  80 #include "net/socket/tcp_client_socket.h"
  81 #include "net/spdy/spdy_session.h"
  82 #include "net/ssl/channel_id_service.h"
  83 #include "net/ssl/default_channel_id_store.h"
  84 #include "net/url_request/data_protocol_handler.h"
  85 #include "net/url_request/file_protocol_handler.h"
  86 #include "net/url_request/ftp_protocol_handler.h"
  87 #include "net/url_request/static_http_user_agent_settings.h"
  88 #include "net/url_request/url_fetcher.h"
  89 #include "net/url_request/url_request_backoff_manager.h"
  90 #include "net/url_request/url_request_context.h"
  91 #include "net/url_request/url_request_context_builder.h"
  92 #include "net/url_request/url_request_context_getter.h"
  93 #include "net/url_request/url_request_job_factory_impl.h"
  94 #include "url/url_constants.h"
  95
  96 #if defined(ENABLE_CONFIGURATION_POLICY)
  97 #include "policy/policy_constants.h"
  98 #endif
  99
 100 #if defined(ENABLE_EXTENSIONS)
 101 #include "chrome/browser/extensions/event_router_forwarder.h"
 102 #endif
 103
 104 #if defined(USE_NSS_CERTS) || defined(OS_IOS)
 105 #include "net/cert_net/nss_ocsp.h"
 106 #endif
 107
 108 #if defined(OS_ANDROID)
 109 #include "base/android/build_info.h"
 110 #include "chrome/browser/android/net/external_estimate_provider_android.h"
 111 #endif
 112
 113 #if defined(OS_CHROMEOS)
 114 #include "chrome/browser/chromeos/net/cert_verify_proc_chromeos.h"
 115 #include "chromeos/network/host_resolver_impl_chromeos.h"
 116 #endif
 117
 118 using content::BrowserThread;
 119
 120 class SafeBrowsingURLRequestContext;
 121
 122 // The IOThread object must outlive any tasks posted to the IO thread before the
 123 // Quit task, so base::Bind() calls are not refcounted.
 124
 125 namespace {
 126
 127 const char kTCPFastOpenFieldTrialName[] = "TCPFastOpen";
 128 const char kTCPFastOpenHttpsEnabledGroupName[] = "HttpsEnabled";
 129
 130 const char kQuicFieldTrialName[] = "QUIC";
 131 const char kQuicFieldTrialEnabledGroupName[] = "Enabled";
 132 const char kQuicFieldTrialHttpsEnabledGroupName[] = "HttpsEnabled";
 133
 134 // The SPDY trial composes two different trial plus control groups:
 135 //  * A "holdback" group with SPDY disabled, and corresponding control
 136 //  (SPDY/3.1). The primary purpose of the holdback group is to encourage site
 137 //  operators to do feature detection rather than UA-sniffing. As such, this
 138 //  trial runs continuously.
 139 //  * A SPDY/4 experiment, for SPDY/4 (aka HTTP/2) vs SPDY/3.1 comparisons and
 140 //  eventual SPDY/4 deployment.
 141 const char kSpdyFieldTrialName[] = "SPDY";
 142 const char kSpdyFieldTrialHoldbackGroupNamePrefix[] = "SpdyDisabled";
 143 const char kSpdyFieldTrialSpdy31GroupNamePrefix[] = "Spdy31Enabled";
 144 const char kSpdyFieldTrialSpdy4GroupNamePrefix[] = "Spdy4Enabled";
 145 const char kSpdyFieldTrialParametrizedPrefix[] = "Parametrized";
 146
 147 // Field trial for network quality estimator. Seeds RTT and downstream
 148 // throughput observations with values that correspond to the connection type
 149 // determined by the operating system.
 150 const char kNetworkQualityEstimatorFieldTrialName[] = "NetworkQualityEstimator";
 151
 152 #if defined(OS_MACOSX) && !defined(OS_IOS)
 153 void ObserveKeychainEvents() {
 154   DCHECK_CURRENTLY_ON(BrowserThread::UI);
 155   net::CertDatabase::GetInstance()->SetMessageLoopForKeychainEvents();
 156 }
 157 #endif
 158
 159 // Used for the "system" URLRequestContext.
 160 class SystemURLRequestContext : public net::URLRequestContext {
 161  public:
 162   SystemURLRequestContext() {
 163 #if defined(USE_NSS_CERTS) || defined(OS_IOS)
 164     net::SetURLRequestContextForNSSHttpIO(this);
 165 #endif
 166   }
 167
 168  private:
 169   ~SystemURLRequestContext() override {
 170     AssertNoURLRequests();
 171 #if defined(USE_NSS_CERTS) || defined(OS_IOS)
 172     net::SetURLRequestContextForNSSHttpIO(NULL);
 173 #endif
 174   }
 175 };
 176
 177 scoped_ptr<net::HostResolver> CreateGlobalHostResolver(net::NetLog* net_log) {
 178   TRACE_EVENT0("startup", "IOThread::CreateGlobalHostResolver");
 179   const base::CommandLine& command_line =
 180       *base::CommandLine::ForCurrentProcess();
 181
 182   net::HostResolver::Options options;
 183
 184   // Use the retry attempts override from the command-line, if any.
 185   if (command_line.HasSwitch(switches::kHostResolverRetryAttempts)) {
 186     std::string s =
 187         command_line.GetSwitchValueASCII(switches::kHostResolverRetryAttempts);
 188     // Parse the switch (it should be a non-negative integer).
 189     int n;
 190     if (base::StringToInt(s, &n) && n >= 0) {
 191       options.max_retry_attempts = static_cast<size_t>(n);
 192     } else {
 193       LOG(ERROR) << "Invalid switch for host resolver retry attempts: " << s;
 194     }
 195   }
 196
 197   scoped_ptr<net::HostResolver> global_host_resolver;
 198 #if defined OS_CHROMEOS
 199   global_host_resolver =
 200       chromeos::HostResolverImplChromeOS::CreateSystemResolver(options,
 201                                                                net_log);
 202 #else
 203   global_host_resolver =
 204       net::HostResolver::CreateSystemResolver(options, net_log);
 205 #endif
 206
 207   // If hostname remappings were specified on the command-line, layer these
 208   // rules on top of the real host resolver. This allows forwarding all requests
 209   // through a designated test server.
 210   if (!command_line.HasSwitch(switches::kHostResolverRules))
 211     return global_host_resolver.Pass();
 212
 213   scoped_ptr<net::MappedHostResolver> remapped_resolver(
 214       new net::MappedHostResolver(global_host_resolver.Pass()));
 215   remapped_resolver->SetRulesFromString(
 216       command_line.GetSwitchValueASCII(switches::kHostResolverRules));
 217   return remapped_resolver.Pass();
 218 }
 219
 220 int GetSwitchValueAsInt(const base::CommandLine& command_line,
 221                         const std::string& switch_name) {
 222   int value;
 223   if (!base::StringToInt(command_line.GetSwitchValueASCII(switch_name),
 224                          &value)) {
 225     return 0;
 226   }
 227   return value;
 228 }
 229
 230 // Returns the value associated with |key| in |params| or "" if the
 231 // key is not present in the map.
 232 const std::string& GetVariationParam(
 233     const std::map<std::string, std::string>& params,
 234     const std::string& key) {
 235   std::map<std::string, std::string>::const_iterator it = params.find(key);
 236   if (it == params.end())
 237     return base::EmptyString();
 238
 239   return it->second;
 240 }
 241
 242 // Parse kUseSpdy command line flag options, which may contain the following:
 243 //
 244 //   "off"                      : Disables SPDY support entirely.
 245 //   "no-ping"                  : Disables SPDY ping connection testing.
 246 //   "exclude=<host>"           : Disables SPDY support for the host <host>.
 247 //   "no-compress"              : Disables SPDY header compression.
 248 //   "init-max-streams=<limit>" : Specifies the maximum number of concurrent
 249 //                                streams for a SPDY session, unless the
 250 //                                specifies a different value via SETTINGS.
 251 void ConfigureSpdyGlobalsFromUseSpdyArgument(const std::string& mode,
 252                                              IOThread::Globals* globals) {
 253   static const char kOff[] = "off";
 254   static const char kDisablePing[] = "no-ping";
 255   static const char kExclude[] = "exclude";  // Hosts to exclude
 256   static const char kDisableCompression[] = "no-compress";
 257   static const char kInitialMaxConcurrentStreams[] = "init-max-streams";
 258
 259   for (const base::StringPiece& element : base::SplitStringPiece(
 260            mode, ",", base::TRIM_WHITESPACE, base::SPLIT_WANT_ALL)) {
 261     std::vector<base::StringPiece> name_value = base::SplitStringPiece(
 262         element, "=", base::TRIM_WHITESPACE, base::SPLIT_WANT_ALL);
 263     const base::StringPiece option =
 264         name_value.size() > 0 ? name_value[0] : base::StringPiece();
 265     const base::StringPiece value =
 266         name_value.size() > 1 ? name_value[1] : base::StringPiece();
 267
 268     if (option == kOff) {
 269       net::HttpStreamFactory::set_spdy_enabled(false);
 270       continue;
 271     }
 272     if (option == kDisablePing) {
 273       globals->enable_spdy_ping_based_connection_checking.set(false);
 274       continue;
 275     }
 276     if (option == kExclude) {
 277       globals->forced_spdy_exclusions.insert(
 278           net::HostPortPair::FromURL(GURL(value.as_string())));
 279       continue;
 280     }
 281     if (option == kDisableCompression) {
 282       globals->enable_spdy_compression.set(false);
 283       continue;
 284     }
 285     if (option == kInitialMaxConcurrentStreams) {
 286       int streams;
 287       if (base::StringToInt(value, &streams)) {
 288         globals->initial_max_spdy_concurrent_streams.set(streams);
 289         continue;
 290       }
 291     }
 292     LOG(DFATAL) << "Unrecognized spdy option: " << option.as_string();
 293   }
 294 }
 295
 296 }  // namespace
 297
 298 class IOThread::LoggingNetworkChangeObserver
 299     : public net::NetworkChangeNotifier::IPAddressObserver,
 300       public net::NetworkChangeNotifier::ConnectionTypeObserver,
 301       public net::NetworkChangeNotifier::NetworkChangeObserver {
 302  public:
 303   // |net_log| must remain valid throughout our lifetime.
 304   explicit LoggingNetworkChangeObserver(net::NetLog* net_log)
 305       : net_log_(net_log) {
 306     net::NetworkChangeNotifier::AddIPAddressObserver(this);
 307     net::NetworkChangeNotifier::AddConnectionTypeObserver(this);
 308     net::NetworkChangeNotifier::AddNetworkChangeObserver(this);
 309   }
 310
 311   ~LoggingNetworkChangeObserver() override {
 312     net::NetworkChangeNotifier::RemoveIPAddressObserver(this);
 313     net::NetworkChangeNotifier::RemoveConnectionTypeObserver(this);
 314     net::NetworkChangeNotifier::RemoveNetworkChangeObserver(this);
 315   }
 316
 317   // NetworkChangeNotifier::IPAddressObserver implementation.
 318   void OnIPAddressChanged() override {
 319     VLOG(1) << "Observed a change to the network IP addresses";
 320
 321     net_log_->AddGlobalEntry(net::NetLog::TYPE_NETWORK_IP_ADDRESSES_CHANGED);
 322   }
 323
 324   // NetworkChangeNotifier::ConnectionTypeObserver implementation.
 325   void OnConnectionTypeChanged(
 326       net::NetworkChangeNotifier::ConnectionType type) override {
 327     std::string type_as_string =
 328         net::NetworkChangeNotifier::ConnectionTypeToString(type);
 329
 330     VLOG(1) << "Observed a change to network connectivity state "
 331             << type_as_string;
 332
 333     net_log_->AddGlobalEntry(
 334         net::NetLog::TYPE_NETWORK_CONNECTIVITY_CHANGED,
 335         net::NetLog::StringCallback("new_connection_type", &type_as_string));
 336   }
 337
 338   // NetworkChangeNotifier::NetworkChangeObserver implementation.
 339   void OnNetworkChanged(
 340       net::NetworkChangeNotifier::ConnectionType type) override {
 341     std::string type_as_string =
 342         net::NetworkChangeNotifier::ConnectionTypeToString(type);
 343
 344     VLOG(1) << "Observed a network change to state " << type_as_string;
 345
 346     net_log_->AddGlobalEntry(
 347         net::NetLog::TYPE_NETWORK_CHANGED,
 348         net::NetLog::StringCallback("new_connection_type", &type_as_string));
 349   }
 350
 351  private:
 352   net::NetLog* net_log_;
 353   DISALLOW_COPY_AND_ASSIGN(LoggingNetworkChangeObserver);
 354 };
 355
 356 class SystemURLRequestContextGetter : public net::URLRequestContextGetter {
 357  public:
 358   explicit SystemURLRequestContextGetter(IOThread* io_thread);
 359
 360   // Implementation for net::UrlRequestContextGetter.
 361   net::URLRequestContext* GetURLRequestContext() override;
 362   scoped_refptr<base::SingleThreadTaskRunner> GetNetworkTaskRunner()
 363       const override;
 364
 365  protected:
 366   ~SystemURLRequestContextGetter() override;
 367
 368  private:
 369   IOThread* const io_thread_;  // Weak pointer, owned by BrowserProcess.
 370   scoped_refptr<base::SingleThreadTaskRunner> network_task_runner_;
 371
 372   base::debug::LeakTracker<SystemURLRequestContextGetter> leak_tracker_;
 373 };
 374
 375 SystemURLRequestContextGetter::SystemURLRequestContextGetter(
 376     IOThread* io_thread)
 377     : io_thread_(io_thread),
 378       network_task_runner_(
 379           BrowserThread::GetMessageLoopProxyForThread(BrowserThread::IO)) {
 380 }
 381
 382 SystemURLRequestContextGetter::~SystemURLRequestContextGetter() {}
 383
 384 net::URLRequestContext* SystemURLRequestContextGetter::GetURLRequestContext() {
 385   DCHECK_CURRENTLY_ON(BrowserThread::IO);
 386   DCHECK(io_thread_->globals()->system_request_context.get());
 387
 388   return io_thread_->globals()->system_request_context.get();
 389 }
 390
 391 scoped_refptr<base::SingleThreadTaskRunner>
 392 SystemURLRequestContextGetter::GetNetworkTaskRunner() const {
 393   return network_task_runner_;
 394 }
 395
 396 IOThread::Globals::
 397 SystemRequestContextLeakChecker::SystemRequestContextLeakChecker(
 398     Globals* globals)
 399     : globals_(globals) {
 400   DCHECK(globals_);
 401 }
 402
 403 IOThread::Globals::
 404 SystemRequestContextLeakChecker::~SystemRequestContextLeakChecker() {
 405   if (globals_->system_request_context.get())
 406     globals_->system_request_context->AssertNoURLRequests();
 407 }
 408
 409 IOThread::Globals::Globals()
 410     : system_request_context_leak_checker(this),
 411       ignore_certificate_errors(false),
 412       testing_fixed_http_port(0),
 413       testing_fixed_https_port(0),
 414       enable_user_alternate_protocol_ports(false) {
 415 }
 416
 417 IOThread::Globals::~Globals() {}
 418
 419 // |local_state| is passed in explicitly in order to (1) reduce implicit
 420 // dependencies and (2) make IOThread more flexible for testing.
 421 IOThread::IOThread(
 422     PrefService* local_state,
 423     policy::PolicyService* policy_service,
 424     net_log::ChromeNetLog* net_log,
 425     extensions::EventRouterForwarder* extension_event_router_forwarder)
 426     : net_log_(net_log),
 427 #if defined(ENABLE_EXTENSIONS)
 428       extension_event_router_forwarder_(extension_event_router_forwarder),
 429 #endif
 430       globals_(NULL),
 431       is_spdy_disabled_by_policy_(false),
 432       is_quic_allowed_by_policy_(true),
 433       creation_time_(base::TimeTicks::Now()),
 434       weak_factory_(this) {
 435   auth_schemes_ = local_state->GetString(prefs::kAuthSchemes);
 436   negotiate_disable_cname_lookup_ = local_state->GetBoolean(
 437       prefs::kDisableAuthNegotiateCnameLookup);
 438   negotiate_enable_port_ = local_state->GetBoolean(
 439       prefs::kEnableAuthNegotiatePort);
 440   auth_server_whitelist_ = local_state->GetString(prefs::kAuthServerWhitelist);
 441   auth_delegate_whitelist_ = local_state->GetString(
 442       prefs::kAuthNegotiateDelegateWhitelist);
 443   gssapi_library_name_ = local_state->GetString(prefs::kGSSAPILibraryName);
 444   auth_android_negotiate_account_type_ =
 445       local_state->GetString(prefs::kAuthAndroidNegotiateAccountType);
 446   pref_proxy_config_tracker_.reset(
 447       ProxyServiceFactory::CreatePrefProxyConfigTrackerOfLocalState(
 448           local_state));
 449   ChromeNetworkDelegate::InitializePrefsOnUIThread(
 450       &system_enable_referrers_,
 451       NULL,
 452       NULL,
 453       NULL,
 454       local_state);
 455   ssl_config_service_manager_.reset(
 456       SSLConfigServiceManager::CreateDefaultManager(local_state));
 457
 458   base::Value* dns_client_enabled_default = new base::FundamentalValue(
 459       chrome_browser_net::ConfigureAsyncDnsFieldTrial());
 460   local_state->SetDefaultPrefValue(prefs::kBuiltInDnsClientEnabled,
 461                                    dns_client_enabled_default);
 462   chrome_browser_net::LogAsyncDnsPrefSource(
 463       local_state->FindPreference(prefs::kBuiltInDnsClientEnabled));
 464
 465   dns_client_enabled_.Init(prefs::kBuiltInDnsClientEnabled,
 466                            local_state,
 467                            base::Bind(&IOThread::UpdateDnsClientEnabled,
 468                                       base::Unretained(this)));
 469   dns_client_enabled_.MoveToThread(
 470       BrowserThread::GetMessageLoopProxyForThread(BrowserThread::IO));
 471
 472   quick_check_enabled_.Init(prefs::kQuickCheckEnabled,
 473                             local_state);
 474   quick_check_enabled_.MoveToThread(
 475       BrowserThread::GetMessageLoopProxyForThread(BrowserThread::IO));
 476
 477 #if defined(ENABLE_CONFIGURATION_POLICY)
 478   is_spdy_disabled_by_policy_ = policy_service->GetPolicies(
 479       policy::PolicyNamespace(policy::POLICY_DOMAIN_CHROME, std::string())).Get(
 480           policy::key::kDisableSpdy) != NULL;
 481
 482   const base::Value* value = policy_service->GetPolicies(
 483       policy::PolicyNamespace(policy::POLICY_DOMAIN_CHROME,
 484       std::string())).GetValue(policy::key::kQuicAllowed);
 485   if (value)
 486     value->GetAsBoolean(&is_quic_allowed_by_policy_);
 487 #endif  // ENABLE_CONFIGURATION_POLICY
 488
 489   BrowserThread::SetDelegate(BrowserThread::IO, this);
 490 }
 491
 492 IOThread::~IOThread() {
 493   // This isn't needed for production code, but in tests, IOThread may
 494   // be multiply constructed.
 495   BrowserThread::SetDelegate(BrowserThread::IO, NULL);
 496
 497   pref_proxy_config_tracker_->DetachFromPrefService();
 498   DCHECK(!globals_);
 499 }
 500
 501 IOThread::Globals* IOThread::globals() {
 502   DCHECK_CURRENTLY_ON(BrowserThread::IO);
 503   return globals_;
 504 }
 505
 506 void IOThread::SetGlobalsForTesting(Globals* globals) {
 507   DCHECK_CURRENTLY_ON(BrowserThread::IO);
 508   DCHECK(!globals || !globals_);
 509   globals_ = globals;
 510 }
 511
 512 net_log::ChromeNetLog* IOThread::net_log() {
 513   return net_log_;
 514 }
 515
 516 void IOThread::ChangedToOnTheRecord() {
 517   DCHECK_CURRENTLY_ON(BrowserThread::UI);
 518   BrowserThread::PostTask(
 519       BrowserThread::IO,
 520       FROM_HERE,
 521       base::Bind(&IOThread::ChangedToOnTheRecordOnIOThread,
 522                  base::Unretained(this)));
 523 }
 524
 525 net::URLRequestContextGetter* IOThread::system_url_request_context_getter() {
 526   DCHECK_CURRENTLY_ON(BrowserThread::UI);
 527   if (!system_url_request_context_getter_.get()) {
 528     InitSystemRequestContext();
 529   }
 530   return system_url_request_context_getter_.get();
 531 }
 532
 533 void IOThread::Init() {
 534   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 535   // is fixed.
 536   tracked_objects::ScopedTracker tracking_profile1(
 537       FROM_HERE_WITH_EXPLICIT_FUNCTION("466432 IOThread::InitAsync::Start"));
 538   TRACE_EVENT0("startup", "IOThread::InitAsync");
 539   DCHECK_CURRENTLY_ON(BrowserThread::IO);
 540
 541 #if defined(USE_NSS_CERTS) || defined(OS_IOS)
 542   net::SetMessageLoopForNSSHttpIO();
 543 #endif
 544
 545   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 546   // is fixed.
 547   tracked_objects::ScopedTracker tracking_profile2(
 548       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 549           "466432 IOThread::InitAsync::CommandLineForCurrentProcess"));
 550   const base::CommandLine& command_line =
 551       *base::CommandLine::ForCurrentProcess();
 552
 553   DCHECK(!globals_);
 554   globals_ = new Globals;
 555
 556   // Add an observer that will emit network change events to the ChromeNetLog.
 557   // Assuming NetworkChangeNotifier dispatches in FIFO order, we should be
 558   // logging the network change before other IO thread consumers respond to it.
 559   network_change_observer_.reset(
 560       new LoggingNetworkChangeObserver(net_log_));
 561
 562   // Setup the HistogramWatcher to run on the IO thread.
 563   net::NetworkChangeNotifier::InitHistogramWatcher();
 564
 565 #if defined(ENABLE_EXTENSIONS)
 566   globals_->extension_event_router_forwarder =
 567       extension_event_router_forwarder_;
 568 #endif
 569
 570   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 571   // is fixed.
 572   tracked_objects::ScopedTracker tracking_profile3(
 573       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 574           "466432 IOThread::InitAsync::ChromeNetworkDelegate"));
 575   scoped_ptr<ChromeNetworkDelegate> chrome_network_delegate(
 576       new ChromeNetworkDelegate(extension_event_router_forwarder(),
 577                                 &system_enable_referrers_));
 578
 579   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 580   // is fixed.
 581   tracked_objects::ScopedTracker tracking_profile4(
 582       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 583           "466432 IOThread::InitAsync::CreateGlobalHostResolver"));
 584   globals_->system_network_delegate = chrome_network_delegate.Pass();
 585   globals_->host_resolver = CreateGlobalHostResolver(net_log_);
 586
 587   std::map<std::string, std::string> network_quality_estimator_params;
 588   variations::GetVariationParams(kNetworkQualityEstimatorFieldTrialName,
 589                                  &network_quality_estimator_params);
 590
 591   scoped_ptr<net::ExternalEstimateProvider> external_estimate_provider;
 592 #if defined(OS_ANDROID)
 593   external_estimate_provider.reset(
 594       new chrome::android::ExternalEstimateProviderAndroid());
 595 #endif
 596   // Pass ownership.
 597   globals_->network_quality_estimator.reset(new net::NetworkQualityEstimator(
 598       external_estimate_provider.Pass(), network_quality_estimator_params));
 599
 600   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 601   // is fixed.
 602   tracked_objects::ScopedTracker tracking_profile5(
 603       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 604           "466432 IOThread::InitAsync::UpdateDnsClientEnabled::Start"));
 605   UpdateDnsClientEnabled();
 606   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 607   // is fixed.
 608   tracked_objects::ScopedTracker tracking_profile6(
 609       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 610           "466432 IOThread::InitAsync::UpdateDnsClientEnabled::End"));
 611 #if defined(OS_CHROMEOS)
 612   // Creates a CertVerifyProc that doesn't allow any profile-provided certs.
 613   globals_->cert_verifier.reset(new net::MultiThreadedCertVerifier(
 614       new chromeos::CertVerifyProcChromeOS()));
 615 #else
 616   globals_->cert_verifier.reset(new net::MultiThreadedCertVerifier(
 617       net::CertVerifyProc::CreateDefault()));
 618 #endif
 619
 620   globals_->transport_security_state.reset(new net::TransportSecurityState());
 621
 622   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 623   // is fixed.
 624   tracked_objects::ScopedTracker tracking_profile8(
 625       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 626           "466432 IOThread::InitAsync::CreateLogVerifiers::Start"));
 627   std::vector<scoped_refptr<net::CTLogVerifier>> ct_logs(
 628       net::ct::CreateLogVerifiersForKnownLogs());
 629
 630   // Add logs from command line
 631   if (command_line.HasSwitch(switches::kCertificateTransparencyLog)) {
 632     std::string switch_value = command_line.GetSwitchValueASCII(
 633         switches::kCertificateTransparencyLog);
 634     for (const base::StringPiece& curr_log : base::SplitStringPiece(
 635              switch_value, ",", base::TRIM_WHITESPACE, base::SPLIT_WANT_ALL)) {
 636       std::vector<std::string> log_metadata = base::SplitString(
 637           curr_log, ":", base::TRIM_WHITESPACE, base::SPLIT_WANT_ALL);
 638       CHECK_GE(log_metadata.size(), 3u)
 639           << "CT log metadata missing: Switch format is "
 640           << "'description:base64_key:url_without_schema'.";
 641       std::string log_description(log_metadata[0]);
 642       std::string log_url(std::string("https://") + log_metadata[2]);
 643       std::string ct_public_key_data;
 644       CHECK(base::Base64Decode(log_metadata[1], &ct_public_key_data))
 645           << "Unable to decode CT public key.";
 646       scoped_refptr<net::CTLogVerifier> external_log_verifier(
 647           net::CTLogVerifier::Create(ct_public_key_data, log_description,
 648                                      log_url));
 649       CHECK(external_log_verifier) << "Unable to parse CT public key.";
 650       VLOG(1) << "Adding log with description " << log_description;
 651       ct_logs.push_back(external_log_verifier);
 652     }
 653   }
 654
 655   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 656   // is fixed.
 657   tracked_objects::ScopedTracker tracking_profile9(
 658       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 659           "466432 IOThread::InitAsync::CreateLogVerifiers::End"));
 660   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 661   // is fixed.
 662   tracked_objects::ScopedTracker tracking_profile7(
 663       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 664           "466432 IOThread::InitAsync::CreateMultiLogVerifier"));
 665   net::MultiLogCTVerifier* ct_verifier = new net::MultiLogCTVerifier();
 666   globals_->cert_transparency_verifier.reset(ct_verifier);
 667   // Add built-in logs
 668   ct_verifier->AddLogs(ct_logs);
 669
 670   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 671   // is fixed.
 672   tracked_objects::ScopedTracker tracking_profile10(
 673       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 674           "466432 IOThread::InitAsync::CertPolicyEnforcer"));
 675   net::CertPolicyEnforcer* policy_enforcer = new net::CertPolicyEnforcer;
 676   globals_->cert_policy_enforcer.reset(policy_enforcer);
 677
 678   globals_->ssl_config_service = GetSSLConfigService();
 679
 680   globals_->http_auth_handler_factory.reset(CreateDefaultAuthHandlerFactory(
 681       globals_->host_resolver.get()));
 682   globals_->http_server_properties.reset(new net::HttpServerPropertiesImpl());
 683   // For the ProxyScriptFetcher, we use a direct ProxyService.
 684   globals_->proxy_script_fetcher_proxy_service =
 685       net::ProxyService::CreateDirectWithNetLog(net_log_);
 686   // In-memory cookie store.
 687   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 688   // is fixed.
 689   tracked_objects::ScopedTracker tracking_profile11(
 690       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 691           "466432 IOThread::InitAsync::CreateCookieStore::Start"));
 692   globals_->system_cookie_store =
 693         content::CreateCookieStore(content::CookieStoreConfig());
 694   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 695   // is fixed.
 696   tracked_objects::ScopedTracker tracking_profile12(
 697       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 698           "466432 IOThread::InitAsync::CreateCookieStore::End"));
 699   // In-memory channel ID store.
 700   globals_->system_channel_id_service.reset(
 701       new net::ChannelIDService(
 702           new net::DefaultChannelIDStore(NULL),
 703           base::WorkerPool::GetTaskRunner(true)));
 704   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 705   // is fixed.
 706   tracked_objects::ScopedTracker tracking_profile12_1(
 707       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 708           "466432 IOThread::InitAsync::CreateDnsProbeService"));
 709   globals_->dns_probe_service.reset(new chrome_browser_net::DnsProbeService());
 710   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 711   // is fixed.
 712   tracked_objects::ScopedTracker tracking_profile12_2(
 713       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 714           "466432 IOThread::InitAsync::CreateHostMappingRules"));
 715   globals_->host_mapping_rules.reset(new net::HostMappingRules());
 716   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 717   // is fixed.
 718   tracked_objects::ScopedTracker tracking_profile12_3(
 719       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 720           "466432 IOThread::InitAsync::CreateHTTPUserAgentSettings"));
 721   globals_->http_user_agent_settings.reset(
 722       new net::StaticHttpUserAgentSettings(std::string(), GetUserAgent()));
 723   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 724   // is fixed.
 725   tracked_objects::ScopedTracker tracking_profile12_4(
 726       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 727           "466432 IOThread::InitAsync::CommandLineConfiguration"));
 728   if (command_line.HasSwitch(switches::kHostRules)) {
 729     TRACE_EVENT_BEGIN0("startup", "IOThread::InitAsync:SetRulesFromString");
 730     globals_->host_mapping_rules->SetRulesFromString(
 731         command_line.GetSwitchValueASCII(switches::kHostRules));
 732     TRACE_EVENT_END0("startup", "IOThread::InitAsync:SetRulesFromString");
 733   }
 734   if (command_line.HasSwitch(switches::kIgnoreCertificateErrors))
 735     globals_->ignore_certificate_errors = true;
 736   if (command_line.HasSwitch(switches::kTestingFixedHttpPort)) {
 737     globals_->testing_fixed_http_port =
 738         GetSwitchValueAsInt(command_line, switches::kTestingFixedHttpPort);
 739   }
 740   if (command_line.HasSwitch(switches::kTestingFixedHttpsPort)) {
 741     globals_->testing_fixed_https_port =
 742         GetSwitchValueAsInt(command_line, switches::kTestingFixedHttpsPort);
 743   }
 744   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 745   // is fixed.
 746   tracked_objects::ScopedTracker tracking_profile12_5(
 747       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 748           "466432 IOThread::InitAsync::QuicConfiguration"));
 749   ConfigureQuic(command_line);
 750   if (command_line.HasSwitch(
 751           switches::kEnableUserAlternateProtocolPorts)) {
 752     globals_->enable_user_alternate_protocol_ports = true;
 753   }
 754   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
 755   // is fixed.
 756   tracked_objects::ScopedTracker tracking_profile13(
 757       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 758           "466432 IOThread::InitAsync::InitializeNetworkOptions"));
 759   InitializeNetworkOptions(command_line);
 760
 761   TRACE_EVENT_BEGIN0("startup",
 762                      "IOThread::Init:ProxyScriptFetcherRequestContext");
 763   globals_->proxy_script_fetcher_context.reset(
 764       ConstructProxyScriptFetcherContext(globals_, net_log_));
 765   TRACE_EVENT_END0("startup",
 766                    "IOThread::Init:ProxyScriptFetcherRequestContext");
 767
 768   const version_info::Channel channel = chrome::GetChannel();
 769   if (channel == version_info::Channel::UNKNOWN ||
 770       channel == version_info::Channel::CANARY ||
 771       channel == version_info::Channel::DEV) {
 772     globals_->url_request_backoff_manager.reset(
 773         new net::URLRequestBackoffManager());
 774   }
 775
 776 #if defined(OS_MACOSX) && !defined(OS_IOS)
 777   // Start observing Keychain events. This needs to be done on the UI thread,
 778   // as Keychain services requires a CFRunLoop.
 779   BrowserThread::PostTask(BrowserThread::UI,
 780                           FROM_HERE,
 781                           base::Bind(&ObserveKeychainEvents));
 782 #endif
 783
 784   // InitSystemRequestContext turns right around and posts a task back
 785   // to the IO thread, so we can't let it run until we know the IO
 786   // thread has started.
 787   //
 788   // Note that since we are at BrowserThread::Init time, the UI thread
 789   // is blocked waiting for the thread to start.  Therefore, posting
 790   // this task to the main thread's message loop here is guaranteed to
 791   // get it onto the message loop while the IOThread object still
 792   // exists.  However, the message might not be processed on the UI
 793   // thread until after IOThread is gone, so use a weak pointer.
 794   BrowserThread::PostTask(BrowserThread::UI,
 795                           FROM_HERE,
 796                           base::Bind(&IOThread::InitSystemRequestContext,
 797                                      weak_factory_.GetWeakPtr()));
 798 }
 799
 800 void IOThread::CleanUp() {
 801   base::debug::LeakTracker<SafeBrowsingURLRequestContext>::CheckForLeaks();
 802
 803 #if defined(USE_NSS_CERTS) || defined(OS_IOS)
 804   net::ShutdownNSSHttpIO();
 805 #endif
 806
 807   system_url_request_context_getter_ = NULL;
 808
 809   // Release objects that the net::URLRequestContext could have been pointing
 810   // to.
 811
 812   // Shutdown the HistogramWatcher on the IO thread.
 813   net::NetworkChangeNotifier::ShutdownHistogramWatcher();
 814
 815   // This must be reset before the ChromeNetLog is destroyed.
 816   network_change_observer_.reset();
 817
 818   system_proxy_config_service_.reset();
 819
 820   delete globals_;
 821   globals_ = NULL;
 822
 823   base::debug::LeakTracker<SystemURLRequestContextGetter>::CheckForLeaks();
 824 }
 825
 826 void IOThread::InitializeNetworkOptions(const base::CommandLine& command_line) {
 827   // Only handle use-spdy command line flags if "spdy.disabled" preference is
 828   // not disabled via policy.
 829   if (is_spdy_disabled_by_policy_) {
 830     base::FieldTrial* trial = base::FieldTrialList::Find(kSpdyFieldTrialName);
 831     if (trial)
 832       trial->Disable();
 833   } else {
 834     std::string group = base::FieldTrialList::FindFullName(kSpdyFieldTrialName);
 835     VariationParameters params;
 836     if (!variations::GetVariationParams(kSpdyFieldTrialName, &params)) {
 837       params.clear();
 838     }
 839     ConfigureSpdyGlobals(command_line, group, params, globals_);
 840   }
 841
 842   ConfigureTCPFastOpen(command_line);
 843
 844   // TODO(rch): Make the client socket factory a per-network session
 845   // instance, constructed from a NetworkSession::Params, to allow us
 846   // to move this option to IOThread::Globals &
 847   // HttpNetworkSession::Params.
 848 }
 849
 850 void IOThread::ConfigureTCPFastOpen(const base::CommandLine& command_line) {
 851   const std::string trial_group =
 852       base::FieldTrialList::FindFullName(kTCPFastOpenFieldTrialName);
 853   if (trial_group == kTCPFastOpenHttpsEnabledGroupName)
 854     globals_->enable_tcp_fast_open_for_ssl.set(true);
 855   bool always_enable_if_supported =
 856       command_line.HasSwitch(switches::kEnableTcpFastOpen);
 857   // Check for OS support of TCP FastOpen, and turn it on for all connections
 858   // if indicated by user.
 859   net::CheckSupportAndMaybeEnableTCPFastOpen(always_enable_if_supported);
 860 }
 861
 862 void IOThread::ConfigureSpdyGlobals(
 863     const base::CommandLine& command_line,
 864     base::StringPiece spdy_trial_group,
 865     const VariationParameters& spdy_trial_params,
 866     IOThread::Globals* globals) {
 867   if (command_line.HasSwitch(switches::kTrustedSpdyProxy)) {
 868     globals->trusted_spdy_proxy.set(
 869         command_line.GetSwitchValueASCII(switches::kTrustedSpdyProxy));
 870   }
 871   if (command_line.HasSwitch(switches::kIgnoreUrlFetcherCertRequests))
 872     net::URLFetcher::SetIgnoreCertificateRequests(true);
 873
 874   if (command_line.HasSwitch(switches::kUseSpdy)) {
 875     std::string spdy_mode =
 876         command_line.GetSwitchValueASCII(switches::kUseSpdy);
 877     ConfigureSpdyGlobalsFromUseSpdyArgument(spdy_mode, globals);
 878     return;
 879   }
 880
 881   globals->next_protos.clear();
 882   globals->next_protos.push_back(net::kProtoHTTP11);
 883   bool enable_quic = false;
 884   globals->enable_quic.CopyToIfSet(&enable_quic);
 885   if (enable_quic) {
 886     globals->next_protos.push_back(net::kProtoQUIC1SPDY3);
 887   }
 888
 889   // No SPDY command-line flags have been specified. Examine trial groups.
 890   if (spdy_trial_group.starts_with(kSpdyFieldTrialHoldbackGroupNamePrefix)) {
 891     net::HttpStreamFactory::set_spdy_enabled(false);
 892     return;
 893   }
 894   if (spdy_trial_group.starts_with(kSpdyFieldTrialSpdy31GroupNamePrefix)) {
 895     globals->next_protos.push_back(net::kProtoSPDY31);
 896     return;
 897   }
 898   if (spdy_trial_group.starts_with(kSpdyFieldTrialSpdy4GroupNamePrefix)) {
 899     globals->next_protos.push_back(net::kProtoSPDY31);
 900     globals->next_protos.push_back(net::kProtoHTTP2);
 901     return;
 902   }
 903   if (spdy_trial_group.starts_with(kSpdyFieldTrialParametrizedPrefix)) {
 904     bool spdy_enabled = false;
 905     if (base::LowerCaseEqualsASCII(
 906             GetVariationParam(spdy_trial_params, "enable_spdy31"), "true")) {
 907       globals->next_protos.push_back(net::kProtoSPDY31);
 908       spdy_enabled = true;
 909     }
 910     if (base::LowerCaseEqualsASCII(
 911             GetVariationParam(spdy_trial_params, "enable_http2"), "true")) {
 912       globals->next_protos.push_back(net::kProtoHTTP2);
 913       spdy_enabled = true;
 914     }
 915     // TODO(bnc): HttpStreamFactory::spdy_enabled_ is redundant with
 916     // globals->next_protos, can it be eliminated?
 917     net::HttpStreamFactory::set_spdy_enabled(spdy_enabled);
 918     return;
 919   }
 920
 921   // By default, enable HTTP/2.
 922   globals->next_protos.push_back(net::kProtoSPDY31);
 923   globals->next_protos.push_back(net::kProtoHTTP2);
 924 }
 925
 926 void IOThread::RegisterPrefs(PrefRegistrySimple* registry) {
 927   registry->RegisterStringPref(prefs::kAuthSchemes,
 928                                "basic,digest,ntlm,negotiate");
 929   registry->RegisterBooleanPref(prefs::kDisableAuthNegotiateCnameLookup, false);
 930   registry->RegisterBooleanPref(prefs::kEnableAuthNegotiatePort, false);
 931   registry->RegisterStringPref(prefs::kAuthServerWhitelist, std::string());
 932   registry->RegisterStringPref(prefs::kAuthNegotiateDelegateWhitelist,
 933                                std::string());
 934   registry->RegisterStringPref(prefs::kGSSAPILibraryName, std::string());
 935   registry->RegisterStringPref(prefs::kAuthAndroidNegotiateAccountType,
 936                                std::string());
 937   registry->RegisterStringPref(
 938       data_reduction_proxy::prefs::kDataReductionProxy, std::string());
 939   registry->RegisterBooleanPref(prefs::kEnableReferrers, true);
 940   data_reduction_proxy::RegisterPrefs(registry);
 941   registry->RegisterBooleanPref(prefs::kBuiltInDnsClientEnabled, true);
 942   registry->RegisterBooleanPref(prefs::kQuickCheckEnabled, true);
 943 }
 944
 945 net::HttpAuthHandlerFactory* IOThread::CreateDefaultAuthHandlerFactory(
 946     net::HostResolver* resolver) {
 947   net::HttpAuthFilterWhitelist* auth_filter_default_credentials = NULL;
 948   if (!auth_server_whitelist_.empty()) {
 949     auth_filter_default_credentials =
 950         new net::HttpAuthFilterWhitelist(auth_server_whitelist_);
 951   }
 952   net::HttpAuthFilterWhitelist* auth_filter_delegate = NULL;
 953   if (!auth_delegate_whitelist_.empty()) {
 954     auth_filter_delegate =
 955         new net::HttpAuthFilterWhitelist(auth_delegate_whitelist_);
 956   }
 957   globals_->url_security_manager.reset(
 958       net::URLSecurityManager::Create(auth_filter_default_credentials,
 959                                       auth_filter_delegate));
 960   std::vector<std::string> supported_schemes = base::SplitString(
 961       auth_schemes_, ",", base::TRIM_WHITESPACE, base::SPLIT_WANT_ALL);
 962
 963   scoped_ptr<net::HttpAuthHandlerRegistryFactory> registry_factory(
 964       net::HttpAuthHandlerRegistryFactory::Create(
 965           supported_schemes, globals_->url_security_manager.get(), resolver,
 966           gssapi_library_name_, auth_android_negotiate_account_type_,
 967           negotiate_disable_cname_lookup_, negotiate_enable_port_));
 968   return registry_factory.release();
 969 }
 970
 971 void IOThread::ClearHostCache() {
 972   DCHECK_CURRENTLY_ON(BrowserThread::IO);
 973
 974   net::HostCache* host_cache = globals_->host_resolver->GetHostCache();
 975   if (host_cache)
 976     host_cache->clear();
 977 }
 978
 979 void IOThread::InitializeNetworkSessionParams(
 980     net::HttpNetworkSession::Params* params) {
 981   InitializeNetworkSessionParamsFromGlobals(*globals_, params);
 982 }
 983
 984 void IOThread::InitializeNetworkSessionParamsFromGlobals(
 985     const IOThread::Globals& globals,
 986     net::HttpNetworkSession::Params* params) {
 987   //  The next two properties of the params don't seem to be
 988   // elements of URLRequestContext, so they must be set here.
 989   params->cert_policy_enforcer = globals.cert_policy_enforcer.get();
 990   params->host_mapping_rules = globals.host_mapping_rules.get();
 991
 992   params->ignore_certificate_errors = globals.ignore_certificate_errors;
 993   params->testing_fixed_http_port = globals.testing_fixed_http_port;
 994   params->testing_fixed_https_port = globals.testing_fixed_https_port;
 995   globals.enable_tcp_fast_open_for_ssl.CopyToIfSet(
 996       &params->enable_tcp_fast_open_for_ssl);
 997
 998   globals.initial_max_spdy_concurrent_streams.CopyToIfSet(
 999       &params->spdy_initial_max_concurrent_streams);
1000   globals.enable_spdy_compression.CopyToIfSet(
1001       &params->enable_spdy_compression);
1002   globals.enable_spdy_ping_based_connection_checking.CopyToIfSet(
1003       &params->enable_spdy_ping_based_connection_checking);
1004   globals.spdy_default_protocol.CopyToIfSet(
1005       &params->spdy_default_protocol);
1006   params->next_protos = globals.next_protos;
1007   globals.trusted_spdy_proxy.CopyToIfSet(&params->trusted_spdy_proxy);
1008   params->forced_spdy_exclusions = globals.forced_spdy_exclusions;
1009   globals.use_alternative_services.CopyToIfSet(
1010       &params->use_alternative_services);
1011   globals.alternative_service_probability_threshold.CopyToIfSet(
1012       &params->alternative_service_probability_threshold);
1013
1014   globals.enable_quic.CopyToIfSet(&params->enable_quic);
1015   globals.enable_insecure_quic.CopyToIfSet(&params->enable_insecure_quic);
1016   globals.enable_quic_for_proxies.CopyToIfSet(&params->enable_quic_for_proxies);
1017   globals.quic_always_require_handshake_confirmation.CopyToIfSet(
1018       &params->quic_always_require_handshake_confirmation);
1019   globals.quic_disable_connection_pooling.CopyToIfSet(
1020       &params->quic_disable_connection_pooling);
1021   globals.quic_load_server_info_timeout_srtt_multiplier.CopyToIfSet(
1022       &params->quic_load_server_info_timeout_srtt_multiplier);
1023   globals.quic_enable_connection_racing.CopyToIfSet(
1024       &params->quic_enable_connection_racing);
1025   globals.quic_enable_non_blocking_io.CopyToIfSet(
1026       &params->quic_enable_non_blocking_io);
1027   globals.quic_prefer_aes.CopyToIfSet(&params->quic_prefer_aes);
1028   globals.quic_disable_disk_cache.CopyToIfSet(
1029       &params->quic_disable_disk_cache);
1030   globals.quic_max_number_of_lossy_connections.CopyToIfSet(
1031       &params->quic_max_number_of_lossy_connections);
1032   globals.quic_packet_loss_threshold.CopyToIfSet(
1033       &params->quic_packet_loss_threshold);
1034   globals.quic_socket_receive_buffer_size.CopyToIfSet(
1035       &params->quic_socket_receive_buffer_size);
1036   globals.quic_delay_tcp_race.CopyToIfSet(&params->quic_delay_tcp_race);
1037   globals.enable_quic_port_selection.CopyToIfSet(
1038       &params->enable_quic_port_selection);
1039   globals.quic_max_packet_length.CopyToIfSet(&params->quic_max_packet_length);
1040   globals.quic_user_agent_id.CopyToIfSet(&params->quic_user_agent_id);
1041   globals.quic_supported_versions.CopyToIfSet(
1042       &params->quic_supported_versions);
1043   params->quic_connection_options = globals.quic_connection_options;
1044
1045   globals.origin_to_force_quic_on.CopyToIfSet(
1046       &params->origin_to_force_quic_on);
1047   params->enable_user_alternate_protocol_ports =
1048       globals.enable_user_alternate_protocol_ports;
1049 }
1050
1051 base::TimeTicks IOThread::creation_time() const {
1052   return creation_time_;
1053 }
1054
1055 net::SSLConfigService* IOThread::GetSSLConfigService() {
1056   return ssl_config_service_manager_->Get();
1057 }
1058
1059 void IOThread::ChangedToOnTheRecordOnIOThread() {
1060   DCHECK_CURRENTLY_ON(BrowserThread::IO);
1061
1062   // Clear the host cache to avoid showing entries from the OTR session
1063   // in about:net-internals.
1064   ClearHostCache();
1065 }
1066
1067 void IOThread::InitSystemRequestContext() {
1068   if (system_url_request_context_getter_.get())
1069     return;
1070   // If we're in unit_tests, IOThread may not be run.
1071   if (!BrowserThread::IsMessageLoopValid(BrowserThread::IO))
1072     return;
1073   system_proxy_config_service_.reset(
1074       ProxyServiceFactory::CreateProxyConfigService(
1075           pref_proxy_config_tracker_.get()));
1076   system_url_request_context_getter_ =
1077       new SystemURLRequestContextGetter(this);
1078   // Safe to post an unretained this pointer, since IOThread is
1079   // guaranteed to outlive the IO BrowserThread.
1080   BrowserThread::PostTask(
1081       BrowserThread::IO,
1082       FROM_HERE,
1083       base::Bind(&IOThread::InitSystemRequestContextOnIOThread,
1084                  base::Unretained(this)));
1085 }
1086
1087 void IOThread::InitSystemRequestContextOnIOThread() {
1088   DCHECK_CURRENTLY_ON(BrowserThread::IO);
1089   DCHECK(!globals_->system_proxy_service.get());
1090   DCHECK(system_proxy_config_service_.get());
1091
1092   const base::CommandLine& command_line =
1093       *base::CommandLine::ForCurrentProcess();
1094   globals_->system_proxy_service = ProxyServiceFactory::CreateProxyService(
1095       net_log_, globals_->proxy_script_fetcher_context.get(),
1096       globals_->system_network_delegate.get(),
1097       system_proxy_config_service_.release(), command_line,
1098       quick_check_enabled_.GetValue());
1099
1100   globals_->system_request_context.reset(
1101       ConstructSystemRequestContext(globals_, net_log_));
1102 }
1103
1104 void IOThread::UpdateDnsClientEnabled() {
1105   globals()->host_resolver->SetDnsClientEnabled(*dns_client_enabled_);
1106 }
1107
1108 void IOThread::ConfigureQuic(const base::CommandLine& command_line) {
1109   // Always fetch the field trial group to ensure it is reported correctly.
1110   // The command line flags will be associated with a group that is reported
1111   // so long as trial is actually queried.
1112   std::string group =
1113       base::FieldTrialList::FindFullName(kQuicFieldTrialName);
1114   VariationParameters params;
1115   if (!variations::GetVariationParams(kQuicFieldTrialName, &params)) {
1116     params.clear();
1117   }
1118
1119   ConfigureQuicGlobals(command_line, group, params, is_quic_allowed_by_policy_,
1120                        globals_);
1121 }
1122
1123 void IOThread::ConfigureQuicGlobals(
1124     const base::CommandLine& command_line,
1125     base::StringPiece quic_trial_group,
1126     const VariationParameters& quic_trial_params,
1127     bool quic_allowed_by_policy,
1128     IOThread::Globals* globals) {
1129   bool enable_quic = ShouldEnableQuic(command_line, quic_trial_group,
1130                                       quic_allowed_by_policy);
1131   globals->enable_quic.set(enable_quic);
1132   bool enable_quic_for_proxies = ShouldEnableQuicForProxies(
1133       command_line, quic_trial_group, quic_allowed_by_policy);
1134   globals->enable_quic_for_proxies.set(enable_quic_for_proxies);
1135   globals->use_alternative_services.set(
1136       ShouldQuicEnableAlternativeServices(command_line, quic_trial_params));
1137   if (enable_quic) {
1138     globals->enable_insecure_quic.set(
1139         ShouldEnableInsecureQuic(command_line, quic_trial_params));
1140     globals->quic_always_require_handshake_confirmation.set(
1141         ShouldQuicAlwaysRequireHandshakeConfirmation(quic_trial_params));
1142     globals->quic_disable_connection_pooling.set(
1143         ShouldQuicDisableConnectionPooling(quic_trial_params));
1144     int receive_buffer_size = GetQuicSocketReceiveBufferSize(quic_trial_params);
1145     if (receive_buffer_size != 0) {
1146       globals->quic_socket_receive_buffer_size.set(receive_buffer_size);
1147     }
1148     globals->quic_delay_tcp_race.set(ShouldQuicDelayTcpRace(quic_trial_params));
1149     float load_server_info_timeout_srtt_multiplier =
1150         GetQuicLoadServerInfoTimeoutSrttMultiplier(quic_trial_params);
1151     if (load_server_info_timeout_srtt_multiplier != 0) {
1152       globals->quic_load_server_info_timeout_srtt_multiplier.set(
1153           load_server_info_timeout_srtt_multiplier);
1154     }
1155     globals->quic_enable_connection_racing.set(
1156         ShouldQuicEnableConnectionRacing(quic_trial_params));
1157     globals->quic_enable_non_blocking_io.set(
1158         ShouldQuicEnableNonBlockingIO(quic_trial_params));
1159     globals->quic_disable_disk_cache.set(
1160         ShouldQuicDisableDiskCache(quic_trial_params));
1161     globals->quic_prefer_aes.set(
1162         ShouldQuicPreferAes(quic_trial_params));
1163     int max_number_of_lossy_connections = GetQuicMaxNumberOfLossyConnections(
1164         quic_trial_params);
1165     if (max_number_of_lossy_connections != 0) {
1166       globals->quic_max_number_of_lossy_connections.set(
1167           max_number_of_lossy_connections);
1168     }
1169     float packet_loss_threshold = GetQuicPacketLossThreshold(quic_trial_params);
1170     if (packet_loss_threshold != 0)
1171       globals->quic_packet_loss_threshold.set(packet_loss_threshold);
1172     globals->enable_quic_port_selection.set(
1173         ShouldEnableQuicPortSelection(command_line));
1174     globals->quic_connection_options =
1175         GetQuicConnectionOptions(command_line, quic_trial_params);
1176   }
1177
1178   size_t max_packet_length = GetQuicMaxPacketLength(command_line,
1179                                                     quic_trial_params);
1180   if (max_packet_length != 0) {
1181     globals->quic_max_packet_length.set(max_packet_length);
1182   }
1183
1184   std::string quic_user_agent_id = chrome::GetChannelString();
1185   if (!quic_user_agent_id.empty())
1186     quic_user_agent_id.push_back(' ');
1187   quic_user_agent_id.append(
1188       version_info::GetProductNameAndVersionForUserAgent());
1189   quic_user_agent_id.push_back(' ');
1190   quic_user_agent_id.append(content::BuildOSCpuInfo());
1191   globals->quic_user_agent_id.set(quic_user_agent_id);
1192
1193   net::QuicVersion version = GetQuicVersion(command_line, quic_trial_params);
1194   if (version != net::QUIC_VERSION_UNSUPPORTED) {
1195     net::QuicVersionVector supported_versions;
1196     supported_versions.push_back(version);
1197     globals->quic_supported_versions.set(supported_versions);
1198   }
1199
1200   double threshold = GetAlternativeProtocolProbabilityThreshold(
1201       command_line, quic_trial_params);
1202   if (threshold >=0 && threshold <= 1) {
1203     globals->alternative_service_probability_threshold.set(threshold);
1204     globals->http_server_properties->SetAlternativeServiceProbabilityThreshold(
1205         threshold);
1206   }
1207
1208   if (command_line.HasSwitch(switches::kOriginToForceQuicOn)) {
1209     net::HostPortPair quic_origin =
1210         net::HostPortPair::FromString(
1211             command_line.GetSwitchValueASCII(switches::kOriginToForceQuicOn));
1212     if (!quic_origin.IsEmpty()) {
1213       globals->origin_to_force_quic_on.set(quic_origin);
1214     }
1215   }
1216 }
1217
1218 bool IOThread::ShouldEnableQuic(const base::CommandLine& command_line,
1219                                 base::StringPiece quic_trial_group,
1220                                 bool quic_allowed_by_policy) {
1221   if (command_line.HasSwitch(switches::kDisableQuic) || !quic_allowed_by_policy)
1222     return false;
1223
1224   if (command_line.HasSwitch(switches::kEnableQuic))
1225     return true;
1226
1227   return quic_trial_group.starts_with(kQuicFieldTrialEnabledGroupName) ||
1228       quic_trial_group.starts_with(kQuicFieldTrialHttpsEnabledGroupName);
1229 }
1230
1231 bool IOThread::ShouldEnableQuicForProxies(const base::CommandLine& command_line,
1232                                           base::StringPiece quic_trial_group,
1233                                           bool quic_allowed_by_policy) {
1234   return ShouldEnableQuic(
1235       command_line, quic_trial_group, quic_allowed_by_policy) ||
1236       ShouldEnableQuicForDataReductionProxy();
1237 }
1238
1239 bool IOThread::ShouldEnableQuicForDataReductionProxy() {
1240   const base::CommandLine& command_line =
1241         *base::CommandLine::ForCurrentProcess();
1242
1243   if (command_line.HasSwitch(switches::kDisableQuic))
1244     return false;
1245
1246   return data_reduction_proxy::params::IsIncludedInQuicFieldTrial();
1247 }
1248
1249 bool IOThread::ShouldEnableInsecureQuic(
1250     const base::CommandLine& command_line,
1251     const VariationParameters& quic_trial_params) {
1252   if (command_line.HasSwitch(switches::kEnableInsecureQuic))
1253     return true;
1254
1255   return base::LowerCaseEqualsASCII(
1256       GetVariationParam(quic_trial_params, "enable_insecure_quic"),
1257       "true");
1258 }
1259
1260 bool IOThread::ShouldEnableQuicPortSelection(
1261     const base::CommandLine& command_line) {
1262   if (command_line.HasSwitch(switches::kDisableQuicPortSelection))
1263     return false;
1264
1265   if (command_line.HasSwitch(switches::kEnableQuicPortSelection))
1266     return true;
1267
1268   return false;  // Default to disabling port selection on all channels.
1269 }
1270
1271 net::QuicTagVector IOThread::GetQuicConnectionOptions(
1272     const base::CommandLine& command_line,
1273     const VariationParameters& quic_trial_params) {
1274   if (command_line.HasSwitch(switches::kQuicConnectionOptions)) {
1275     return net::QuicUtils::ParseQuicConnectionOptions(
1276         command_line.GetSwitchValueASCII(switches::kQuicConnectionOptions));
1277   }
1278
1279   VariationParameters::const_iterator it =
1280       quic_trial_params.find("connection_options");
1281   if (it == quic_trial_params.end()) {
1282     return net::QuicTagVector();
1283   }
1284
1285   return net::QuicUtils::ParseQuicConnectionOptions(it->second);
1286 }
1287
1288 double IOThread::GetAlternativeProtocolProbabilityThreshold(
1289     const base::CommandLine& command_line,
1290     const VariationParameters& quic_trial_params) {
1291   double value;
1292   if (command_line.HasSwitch(
1293           switches::kAlternativeServiceProbabilityThreshold)) {
1294     if (base::StringToDouble(
1295             command_line.GetSwitchValueASCII(
1296                 switches::kAlternativeServiceProbabilityThreshold),
1297             &value)) {
1298       return value;
1299     }
1300   }
1301   if (command_line.HasSwitch(switches::kEnableQuic)) {
1302     return 0;
1303   }
1304   // TODO(bnc): Remove when new parameter name rolls out and server
1305   // configuration is changed.
1306   if (base::StringToDouble(
1307           GetVariationParam(quic_trial_params,
1308                             "alternate_protocol_probability_threshold"),
1309           &value)) {
1310     return value;
1311   }
1312   if (base::StringToDouble(
1313           GetVariationParam(quic_trial_params,
1314                             "alternative_service_probability_threshold"),
1315           &value)) {
1316     return value;
1317   }
1318   return -1;
1319 }
1320
1321 bool IOThread::ShouldQuicAlwaysRequireHandshakeConfirmation(
1322     const VariationParameters& quic_trial_params) {
1323   return base::LowerCaseEqualsASCII(
1324       GetVariationParam(quic_trial_params,
1325                         "always_require_handshake_confirmation"),
1326       "true");
1327 }
1328
1329 bool IOThread::ShouldQuicDisableConnectionPooling(
1330     const VariationParameters& quic_trial_params) {
1331   return base::LowerCaseEqualsASCII(
1332       GetVariationParam(quic_trial_params, "disable_connection_pooling"),
1333       "true");
1334 }
1335
1336 float IOThread::GetQuicLoadServerInfoTimeoutSrttMultiplier(
1337     const VariationParameters& quic_trial_params) {
1338   double value;
1339   if (base::StringToDouble(GetVariationParam(quic_trial_params,
1340                                              "load_server_info_time_to_srtt"),
1341                            &value)) {
1342     return static_cast<float>(value);
1343   }
1344   return 0.0f;
1345 }
1346
1347 bool IOThread::ShouldQuicEnableConnectionRacing(
1348     const VariationParameters& quic_trial_params) {
1349   return base::LowerCaseEqualsASCII(
1350       GetVariationParam(quic_trial_params, "enable_connection_racing"),
1351       "true");
1352 }
1353
1354 bool IOThread::ShouldQuicEnableNonBlockingIO(
1355     const VariationParameters& quic_trial_params) {
1356   return base::LowerCaseEqualsASCII(
1357       GetVariationParam(quic_trial_params, "enable_non_blocking_io"),
1358       "true");
1359 }
1360
1361 bool IOThread::ShouldQuicDisableDiskCache(
1362     const VariationParameters& quic_trial_params) {
1363   return base::LowerCaseEqualsASCII(
1364       GetVariationParam(quic_trial_params, "disable_disk_cache"), "true");
1365 }
1366
1367 bool IOThread::ShouldQuicPreferAes(
1368     const VariationParameters& quic_trial_params) {
1369   return base::LowerCaseEqualsASCII(
1370       GetVariationParam(quic_trial_params, "prefer_aes"), "true");
1371 }
1372
1373 bool IOThread::ShouldQuicEnableAlternativeServices(
1374     const base::CommandLine& command_line,
1375     const VariationParameters& quic_trial_params) {
1376   return command_line.HasSwitch(switches::kEnableAlternativeServices) ||
1377          base::LowerCaseEqualsASCII(
1378              GetVariationParam(quic_trial_params, "use_alternative_services"),
1379              "true");
1380 }
1381
1382 int IOThread::GetQuicMaxNumberOfLossyConnections(
1383     const VariationParameters& quic_trial_params) {
1384   int value;
1385   if (base::StringToInt(GetVariationParam(quic_trial_params,
1386                                           "max_number_of_lossy_connections"),
1387                         &value)) {
1388     return value;
1389   }
1390   return 0;
1391 }
1392
1393 float IOThread::GetQuicPacketLossThreshold(
1394     const VariationParameters& quic_trial_params) {
1395   double value;
1396   if (base::StringToDouble(GetVariationParam(quic_trial_params,
1397                                              "packet_loss_threshold"),
1398                            &value)) {
1399     return static_cast<float>(value);
1400   }
1401   return 0.0f;
1402 }
1403
1404 int IOThread::GetQuicSocketReceiveBufferSize(
1405     const VariationParameters& quic_trial_params) {
1406   int value;
1407   if (base::StringToInt(GetVariationParam(quic_trial_params,
1408                                           "receive_buffer_size"),
1409                         &value)) {
1410     return value;
1411   }
1412   return 0;
1413 }
1414
1415 bool IOThread::ShouldQuicDelayTcpRace(
1416     const VariationParameters& quic_trial_params) {
1417   return base::LowerCaseEqualsASCII(
1418       GetVariationParam(quic_trial_params, "delay_tcp_race"), "true");
1419 }
1420
1421 size_t IOThread::GetQuicMaxPacketLength(
1422     const base::CommandLine& command_line,
1423     const VariationParameters& quic_trial_params) {
1424   if (command_line.HasSwitch(switches::kQuicMaxPacketLength)) {
1425     unsigned value;
1426     if (!base::StringToUint(
1427             command_line.GetSwitchValueASCII(switches::kQuicMaxPacketLength),
1428             &value)) {
1429       return 0;
1430     }
1431     return value;
1432   }
1433
1434   unsigned value;
1435   if (base::StringToUint(GetVariationParam(quic_trial_params,
1436                                            "max_packet_length"),
1437                          &value)) {
1438     return value;
1439   }
1440   return 0;
1441 }
1442
1443 net::QuicVersion IOThread::GetQuicVersion(
1444     const base::CommandLine& command_line,
1445     const VariationParameters& quic_trial_params) {
1446   if (command_line.HasSwitch(switches::kQuicVersion)) {
1447     return ParseQuicVersion(
1448         command_line.GetSwitchValueASCII(switches::kQuicVersion));
1449   }
1450
1451   return ParseQuicVersion(GetVariationParam(quic_trial_params, "quic_version"));
1452 }
1453
1454 net::QuicVersion IOThread::ParseQuicVersion(const std::string& quic_version) {
1455   net::QuicVersionVector supported_versions = net::QuicSupportedVersions();
1456   for (size_t i = 0; i < supported_versions.size(); ++i) {
1457     net::QuicVersion version = supported_versions[i];
1458     if (net::QuicVersionToString(version) == quic_version) {
1459       return version;
1460     }
1461   }
1462
1463   return net::QUIC_VERSION_UNSUPPORTED;
1464 }
1465
1466 net::URLRequestContext* IOThread::ConstructSystemRequestContext(
1467     IOThread::Globals* globals,
1468     net::NetLog* net_log) {
1469   net::URLRequestContext* context = new SystemURLRequestContext;
1470   context->set_net_log(net_log);
1471   context->set_host_resolver(globals->host_resolver.get());
1472   context->set_cert_verifier(globals->cert_verifier.get());
1473   context->set_transport_security_state(
1474       globals->transport_security_state.get());
1475   context->set_cert_transparency_verifier(
1476       globals->cert_transparency_verifier.get());
1477   context->set_ssl_config_service(globals->ssl_config_service.get());
1478   context->set_http_auth_handler_factory(
1479       globals->http_auth_handler_factory.get());
1480   context->set_proxy_service(globals->system_proxy_service.get());
1481
1482   globals->system_url_request_job_factory.reset(
1483       new net::URLRequestJobFactoryImpl());
1484   context->set_job_factory(globals->system_url_request_job_factory.get());
1485
1486   context->set_cookie_store(globals->system_cookie_store.get());
1487   context->set_channel_id_service(
1488       globals->system_channel_id_service.get());
1489   context->set_network_delegate(globals->system_network_delegate.get());
1490   context->set_http_user_agent_settings(
1491       globals->http_user_agent_settings.get());
1492   context->set_network_quality_estimator(
1493       globals->network_quality_estimator.get());
1494   context->set_backoff_manager(globals->url_request_backoff_manager.get());
1495
1496   context->set_http_server_properties(
1497       globals->http_server_properties->GetWeakPtr());
1498
1499   net::HttpNetworkSession::Params system_params;
1500   InitializeNetworkSessionParamsFromGlobals(*globals, &system_params);
1501   net::URLRequestContextBuilder::SetHttpNetworkSessionComponents(
1502       context, &system_params);
1503
1504   globals->system_http_transaction_factory.reset(
1505       new net::HttpNetworkLayer(new net::HttpNetworkSession(system_params)));
1506   context->set_http_transaction_factory(
1507       globals->system_http_transaction_factory.get());
1508
1509   return context;
1510 }
1511
1512 net::URLRequestContext* IOThread::ConstructProxyScriptFetcherContext(
1513     IOThread::Globals* globals,
1514     net::NetLog* net_log) {
1515   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
1516   // is fixed.
1517   tracked_objects::ScopedTracker tracking_profile1(
1518       FROM_HERE_WITH_EXPLICIT_FUNCTION(
1519           "466432 IOThread::ConstructProxyScriptFetcherContext1"));
1520   net::URLRequestContext* context = new net::URLRequestContext;
1521   context->set_net_log(net_log);
1522   context->set_host_resolver(globals->host_resolver.get());
1523   context->set_cert_verifier(globals->cert_verifier.get());
1524   context->set_transport_security_state(
1525       globals->transport_security_state.get());
1526   context->set_cert_transparency_verifier(
1527       globals->cert_transparency_verifier.get());
1528   context->set_ssl_config_service(globals->ssl_config_service.get());
1529   context->set_http_auth_handler_factory(
1530       globals->http_auth_handler_factory.get());
1531   context->set_proxy_service(globals->proxy_script_fetcher_proxy_service.get());
1532
1533   context->set_job_factory(
1534       globals->proxy_script_fetcher_url_request_job_factory.get());
1535
1536   context->set_cookie_store(globals->system_cookie_store.get());
1537   context->set_channel_id_service(
1538       globals->system_channel_id_service.get());
1539   context->set_network_delegate(globals->system_network_delegate.get());
1540   context->set_http_user_agent_settings(
1541       globals->http_user_agent_settings.get());
1542   context->set_http_server_properties(
1543       globals->http_server_properties->GetWeakPtr());
1544
1545   net::HttpNetworkSession::Params session_params;
1546   InitializeNetworkSessionParamsFromGlobals(*globals, &session_params);
1547   net::URLRequestContextBuilder::SetHttpNetworkSessionComponents(
1548       context, &session_params);
1549
1550   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
1551   // is fixed.
1552   tracked_objects::ScopedTracker tracking_profile2(
1553       FROM_HERE_WITH_EXPLICIT_FUNCTION(
1554           "466432 IOThread::ConstructProxyScriptFetcherContext2"));
1555   scoped_refptr<net::HttpNetworkSession> network_session(
1556       new net::HttpNetworkSession(session_params));
1557   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
1558   // is fixed.
1559   tracked_objects::ScopedTracker tracking_profile3(
1560       FROM_HERE_WITH_EXPLICIT_FUNCTION(
1561           "466432 IOThread::ConstructProxyScriptFetcherContext3"));
1562   globals->proxy_script_fetcher_http_transaction_factory
1563       .reset(new net::HttpNetworkLayer(network_session.get()));
1564   context->set_http_transaction_factory(
1565       globals->proxy_script_fetcher_http_transaction_factory.get());
1566
1567   scoped_ptr<net::URLRequestJobFactoryImpl> job_factory(
1568       new net::URLRequestJobFactoryImpl());
1569
1570   job_factory->SetProtocolHandler(
1571       url::kDataScheme, make_scoped_ptr(new net::DataProtocolHandler()));
1572   job_factory->SetProtocolHandler(
1573       url::kFileScheme,
1574       make_scoped_ptr(new net::FileProtocolHandler(
1575           content::BrowserThread::GetBlockingPool()
1576               ->GetTaskRunnerWithShutdownBehavior(
1577                   base::SequencedWorkerPool::SKIP_ON_SHUTDOWN))));
1578 #if !defined(DISABLE_FTP_SUPPORT)
1579   globals->proxy_script_fetcher_ftp_transaction_factory.reset(
1580       new net::FtpNetworkLayer(globals->host_resolver.get()));
1581   job_factory->SetProtocolHandler(
1582       url::kFtpScheme,
1583       make_scoped_ptr(new net::FtpProtocolHandler(
1584           globals->proxy_script_fetcher_ftp_transaction_factory.get())));
1585 #endif
1586   globals->proxy_script_fetcher_url_request_job_factory = job_factory.Pass();
1587
1588   context->set_job_factory(
1589       globals->proxy_script_fetcher_url_request_job_factory.get());
1590
1591   // TODO(rtenneti): We should probably use HttpServerPropertiesManager for the
1592   // system URLRequestContext too. There's no reason this should be tied to a
1593   // profile.
1594   return context;
1595 }