src/chrome/browser/net/chrome_network_delegate.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/net/chrome_network_delegate.h"
   6
   7 #include <stdlib.h>
   8
   9 #include <vector>
  10
  11 #include "base/base_paths.h"
  12 #include "base/debug/trace_event.h"
  13 #include "base/logging.h"
  14 #include "base/metrics/histogram.h"
  15 #include "base/path_service.h"
  16 #include "base/prefs/pref_member.h"
  17 #include "base/prefs/pref_service.h"
  18 #include "base/strings/string_number_conversions.h"
  19 #include "base/strings/string_split.h"
  20 #include "base/time/time.h"
  21 #include "chrome/browser/browser_process.h"
  22 #include "chrome/browser/content_settings/cookie_settings.h"
  23 #include "chrome/browser/content_settings/tab_specific_content_settings.h"
  24 #include "chrome/browser/custom_handlers/protocol_handler_registry.h"
  25 #include "chrome/browser/extensions/api/proxy/proxy_api.h"
  26 #include "chrome/browser/extensions/api/web_request/web_request_api.h"
  27 #include "chrome/browser/extensions/event_router_forwarder.h"
  28 #include "chrome/browser/google/google_util.h"
  29 #include "chrome/browser/net/client_hints.h"
  30 #include "chrome/browser/net/connect_interceptor.h"
  31 #include "chrome/browser/net/spdyproxy/data_saving_metrics.h"
  32 #include "chrome/browser/performance_monitor/performance_monitor.h"
  33 #include "chrome/browser/profiles/profile_manager.h"
  34 #include "chrome/browser/task_manager/task_manager.h"
  35 #include "chrome/common/pref_names.h"
  36 #include "chrome/common/url_constants.h"
  37 #include "content/public/browser/browser_thread.h"
  38 #include "content/public/browser/render_frame_host.h"
  39 #include "content/public/browser/render_view_host.h"
  40 #include "content/public/browser/resource_request_info.h"
  41 #include "extensions/browser/extension_system.h"
  42 #include "extensions/browser/info_map.h"
  43 #include "extensions/browser/process_manager.h"
  44 #include "extensions/common/constants.h"
  45 #include "net/base/host_port_pair.h"
  46 #include "net/base/net_errors.h"
  47 #include "net/base/net_log.h"
  48 #include "net/cookies/canonical_cookie.h"
  49 #include "net/cookies/cookie_options.h"
  50 #include "net/http/http_request_headers.h"
  51 #include "net/http/http_response_headers.h"
  52 #include "net/socket_stream/socket_stream.h"
  53 #include "net/url_request/url_request.h"
  54
  55 #if defined(OS_CHROMEOS)
  56 #include "base/command_line.h"
  57 #include "base/sys_info.h"
  58 #include "chrome/common/chrome_switches.h"
  59 #endif
  60
  61 #if defined(ENABLE_CONFIGURATION_POLICY)
  62 #include "components/policy/core/browser/url_blacklist_manager.h"
  63 #endif
  64
  65 #if defined(OS_ANDROID)
  66 #include "components/precache/content/precache_manager.h"
  67 #include "components/precache/content/precache_manager_factory.h"
  68 #endif
  69
  70 using content::BrowserThread;
  71 using content::RenderViewHost;
  72 using content::ResourceRequestInfo;
  73
  74 // By default we don't allow access to all file:// urls on ChromeOS and
  75 // Android.
  76 #if defined(OS_CHROMEOS) || defined(OS_ANDROID)
  77 bool ChromeNetworkDelegate::g_allow_file_access_ = false;
  78 #else
  79 bool ChromeNetworkDelegate::g_allow_file_access_ = true;
  80 #endif
  81
  82 // This remains false unless the --disable-extensions-http-throttling
  83 // flag is passed to the browser.
  84 bool ChromeNetworkDelegate::g_never_throttle_requests_ = false;
  85
  86 namespace {
  87
  88 const char kDNTHeader[] = "DNT";
  89
  90 // If the |request| failed due to problems with a proxy, forward the error to
  91 // the proxy extension API.
  92 void ForwardProxyErrors(net::URLRequest* request,
  93                         extensions::EventRouterForwarder* event_router,
  94                         void* profile) {
  95   if (request->status().status() == net::URLRequestStatus::FAILED) {
  96     switch (request->status().error()) {
  97       case net::ERR_PROXY_AUTH_UNSUPPORTED:
  98       case net::ERR_PROXY_CONNECTION_FAILED:
  99       case net::ERR_TUNNEL_CONNECTION_FAILED:
 100         extensions::ProxyEventRouter::GetInstance()->OnProxyError(
 101             event_router, profile, request->status().error());
 102     }
 103   }
 104 }
 105
 106 // Returns whether a URL parameter, |first_parameter| (e.g. foo=bar), has the
 107 // same key as the the |second_parameter| (e.g. foo=baz). Both parameters
 108 // must be in key=value form.
 109 bool HasSameParameterKey(const std::string& first_parameter,
 110                          const std::string& second_parameter) {
 111   DCHECK(second_parameter.find("=") != std::string::npos);
 112   // Prefix for "foo=bar" is "foo=".
 113   std::string parameter_prefix = second_parameter.substr(
 114       0, second_parameter.find("=") + 1);
 115   return StartsWithASCII(first_parameter, parameter_prefix, false);
 116 }
 117
 118 // Examines the query string containing parameters and adds the necessary ones
 119 // so that SafeSearch is active. |query| is the string to examine and the
 120 // return value is the |query| string modified such that SafeSearch is active.
 121 std::string AddSafeSearchParameters(const std::string& query) {
 122   std::vector<std::string> new_parameters;
 123   std::string safe_parameter = chrome::kSafeSearchSafeParameter;
 124   std::string ssui_parameter = chrome::kSafeSearchSsuiParameter;
 125
 126   std::vector<std::string> parameters;
 127   base::SplitString(query, '&', &parameters);
 128
 129   std::vector<std::string>::iterator it;
 130   for (it = parameters.begin(); it < parameters.end(); ++it) {
 131     if (!HasSameParameterKey(*it, safe_parameter) &&
 132         !HasSameParameterKey(*it, ssui_parameter)) {
 133       new_parameters.push_back(*it);
 134     }
 135   }
 136
 137   new_parameters.push_back(safe_parameter);
 138   new_parameters.push_back(ssui_parameter);
 139   return JoinString(new_parameters, '&');
 140 }
 141
 142 // If |request| is a request to Google Web Search the function
 143 // enforces that the SafeSearch query parameters are set to active.
 144 // Sets the query part of |new_url| with the new value of the parameters.
 145 void ForceGoogleSafeSearch(net::URLRequest* request,
 146                            GURL* new_url) {
 147   if (!google_util::IsGoogleSearchUrl(request->url()) &&
 148       !google_util::IsGoogleHomePageUrl(request->url()))
 149     return;
 150
 151   std::string query = request->url().query();
 152   std::string new_query = AddSafeSearchParameters(query);
 153   if (query == new_query)
 154     return;
 155
 156   GURL::Replacements replacements;
 157   replacements.SetQueryStr(new_query);
 158   *new_url = request->url().ReplaceComponents(replacements);
 159 }
 160
 161 // Gets called when the extensions finish work on the URL. If the extensions
 162 // did not do a redirect (so |new_url| is empty) then we enforce the
 163 // SafeSearch parameters. Otherwise we will get called again after the
 164 // redirect and we enforce SafeSearch then.
 165 void ForceGoogleSafeSearchCallbackWrapper(
 166     const net::CompletionCallback& callback,
 167     net::URLRequest* request,
 168     GURL* new_url,
 169     int rv) {
 170   if (rv == net::OK && new_url->is_empty())
 171     ForceGoogleSafeSearch(request, new_url);
 172   callback.Run(rv);
 173 }
 174
 175 enum RequestStatus { REQUEST_STARTED, REQUEST_DONE };
 176
 177 // Notifies the extensions::ProcessManager that a request has started or stopped
 178 // for a particular RenderFrame.
 179 void NotifyEPMRequestStatus(RequestStatus status,
 180                             void* profile_id,
 181                             int process_id,
 182                             int render_frame_id) {
 183   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 184   Profile* profile = reinterpret_cast<Profile*>(profile_id);
 185   if (!g_browser_process->profile_manager()->IsValidProfile(profile))
 186     return;
 187
 188   extensions::ProcessManager* process_manager =
 189       extensions::ExtensionSystem::Get(profile)->process_manager();
 190   // This may be NULL in unit tests.
 191   if (!process_manager)
 192     return;
 193
 194   // Will be NULL if the request was not issued on behalf of a renderer (e.g. a
 195   // system-level request).
 196   content::RenderFrameHost* render_frame_host =
 197       content::RenderFrameHost::FromID(process_id, render_frame_id);
 198   if (render_frame_host) {
 199     if (status == REQUEST_STARTED) {
 200       process_manager->OnNetworkRequestStarted(render_frame_host);
 201     } else if (status == REQUEST_DONE) {
 202       process_manager->OnNetworkRequestDone(render_frame_host);
 203     } else {
 204       NOTREACHED();
 205     }
 206   }
 207 }
 208
 209 void ForwardRequestStatus(
 210     RequestStatus status, net::URLRequest* request, void* profile_id) {
 211   const ResourceRequestInfo* info = ResourceRequestInfo::ForRequest(request);
 212   if (!info)
 213     return;
 214
 215   int process_id, render_frame_id;
 216   if (info->GetAssociatedRenderFrame(&process_id, &render_frame_id)) {
 217     BrowserThread::PostTask(BrowserThread::UI, FROM_HERE,
 218         base::Bind(&NotifyEPMRequestStatus,
 219                    status, profile_id, process_id, render_frame_id));
 220   }
 221 }
 222
 223 void UpdateContentLengthPrefs(
 224     int received_content_length,
 225     int original_content_length,
 226     spdyproxy::DataReductionRequestType data_reduction_type,
 227     Profile* profile) {
 228   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 229   DCHECK_GE(received_content_length, 0);
 230   DCHECK_GE(original_content_length, 0);
 231
 232   // Can be NULL in a unit test.
 233   if (!g_browser_process)
 234     return;
 235
 236   PrefService* prefs = g_browser_process->local_state();
 237   if (!prefs)
 238     return;
 239
 240   // Ignore off-the-record data.
 241   if (!g_browser_process->profile_manager()->IsValidProfile(profile) ||
 242       profile->IsOffTheRecord()) {
 243     return;
 244   }
 245 #if defined(OS_ANDROID)
 246   // If Android ever goes multi profile, the profile should be passed so that
 247   // the browser preference will be taken.
 248   bool with_data_reduction_proxy_enabled =
 249       ProfileManager::GetActiveUserProfile()->GetPrefs()->GetBoolean(
 250           prefs::kSpdyProxyAuthEnabled);
 251 #else
 252   bool with_data_reduction_proxy_enabled = false;
 253 #endif
 254
 255   spdyproxy::UpdateContentLengthPrefs(received_content_length,
 256                                       original_content_length,
 257                                       with_data_reduction_proxy_enabled,
 258                                       data_reduction_type, prefs);
 259 }
 260
 261 void StoreAccumulatedContentLength(
 262     int received_content_length,
 263     int original_content_length,
 264     spdyproxy::DataReductionRequestType data_reduction_type,
 265     Profile* profile) {
 266   BrowserThread::PostTask(BrowserThread::UI, FROM_HERE,
 267       base::Bind(&UpdateContentLengthPrefs,
 268                  received_content_length, original_content_length,
 269                  data_reduction_type, profile));
 270 }
 271
 272 void RecordContentLengthHistograms(
 273     int64 received_content_length,
 274     int64 original_content_length,
 275     const base::TimeDelta& freshness_lifetime) {
 276 #if defined(OS_ANDROID)
 277   // Add the current resource to these histograms only when a valid
 278   // X-Original-Content-Length header is present.
 279   if (original_content_length >= 0) {
 280     UMA_HISTOGRAM_COUNTS("Net.HttpContentLengthWithValidOCL",
 281                          received_content_length);
 282     UMA_HISTOGRAM_COUNTS("Net.HttpOriginalContentLengthWithValidOCL",
 283                          original_content_length);
 284     UMA_HISTOGRAM_COUNTS("Net.HttpContentLengthDifferenceWithValidOCL",
 285                          original_content_length - received_content_length);
 286   } else {
 287     // Presume the original content length is the same as the received content
 288     // length if the X-Original-Content-Header is not present.
 289     original_content_length = received_content_length;
 290   }
 291   UMA_HISTOGRAM_COUNTS("Net.HttpContentLength", received_content_length);
 292   UMA_HISTOGRAM_COUNTS("Net.HttpOriginalContentLength",
 293                        original_content_length);
 294   UMA_HISTOGRAM_COUNTS("Net.HttpContentLengthDifference",
 295                        original_content_length - received_content_length);
 296   UMA_HISTOGRAM_CUSTOM_COUNTS("Net.HttpContentFreshnessLifetime",
 297                               freshness_lifetime.InSeconds(),
 298                               base::TimeDelta::FromHours(1).InSeconds(),
 299                               base::TimeDelta::FromDays(30).InSeconds(),
 300                               100);
 301   if (freshness_lifetime.InSeconds() <= 0)
 302     return;
 303   UMA_HISTOGRAM_COUNTS("Net.HttpContentLengthCacheable",
 304                        received_content_length);
 305   if (freshness_lifetime.InHours() < 4)
 306     return;
 307   UMA_HISTOGRAM_COUNTS("Net.HttpContentLengthCacheable4Hours",
 308                        received_content_length);
 309
 310   if (freshness_lifetime.InHours() < 24)
 311     return;
 312   UMA_HISTOGRAM_COUNTS("Net.HttpContentLengthCacheable24Hours",
 313                        received_content_length);
 314 #endif  // defined(OS_ANDROID)
 315 }
 316
 317 #if defined(OS_ANDROID)
 318 void RecordPrecacheStatsOnUIThread(const GURL& url,
 319                                    const base::Time& fetch_time, int64 size,
 320                                    bool was_cached, void* profile_id) {
 321   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 322
 323   Profile* profile = reinterpret_cast<Profile*>(profile_id);
 324   if (!g_browser_process->profile_manager()->IsValidProfile(profile)) {
 325     return;
 326   }
 327
 328   precache::PrecacheManager* precache_manager =
 329       precache::PrecacheManagerFactory::GetForBrowserContext(profile);
 330   if (!precache_manager) {
 331     // This could be NULL if the profile is off the record.
 332     return;
 333   }
 334
 335   precache_manager->RecordStatsForFetch(url, fetch_time, size, was_cached);
 336 }
 337 #endif  // defined(OS_ANDROID)
 338
 339 }  // namespace
 340
 341 ChromeNetworkDelegate::ChromeNetworkDelegate(
 342     extensions::EventRouterForwarder* event_router,
 343     BooleanPrefMember* enable_referrers)
 344     : event_router_(event_router),
 345       profile_(NULL),
 346       enable_referrers_(enable_referrers),
 347       enable_do_not_track_(NULL),
 348       force_google_safe_search_(NULL),
 349       url_blacklist_manager_(NULL),
 350       received_content_length_(0),
 351       original_content_length_(0) {
 352   DCHECK(event_router);
 353   DCHECK(enable_referrers);
 354 }
 355
 356 ChromeNetworkDelegate::~ChromeNetworkDelegate() {}
 357
 358 void ChromeNetworkDelegate::set_extension_info_map(
 359     extensions::InfoMap* extension_info_map) {
 360   extension_info_map_ = extension_info_map;
 361 }
 362
 363 void ChromeNetworkDelegate::set_cookie_settings(
 364     CookieSettings* cookie_settings) {
 365   cookie_settings_ = cookie_settings;
 366 }
 367
 368 void ChromeNetworkDelegate::set_predictor(
 369     chrome_browser_net::Predictor* predictor) {
 370   connect_interceptor_.reset(
 371       new chrome_browser_net::ConnectInterceptor(predictor));
 372 }
 373
 374 void ChromeNetworkDelegate::SetEnableClientHints() {
 375   client_hints_.reset(new ClientHints());
 376   client_hints_->Init();
 377 }
 378
 379 // static
 380 void ChromeNetworkDelegate::NeverThrottleRequests() {
 381   g_never_throttle_requests_ = true;
 382 }
 383
 384 // static
 385 void ChromeNetworkDelegate::InitializePrefsOnUIThread(
 386     BooleanPrefMember* enable_referrers,
 387     BooleanPrefMember* enable_do_not_track,
 388     BooleanPrefMember* force_google_safe_search,
 389     PrefService* pref_service) {
 390   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 391   enable_referrers->Init(prefs::kEnableReferrers, pref_service);
 392   enable_referrers->MoveToThread(
 393       BrowserThread::GetMessageLoopProxyForThread(BrowserThread::IO));
 394   if (enable_do_not_track) {
 395     enable_do_not_track->Init(prefs::kEnableDoNotTrack, pref_service);
 396     enable_do_not_track->MoveToThread(
 397         BrowserThread::GetMessageLoopProxyForThread(BrowserThread::IO));
 398   }
 399   if (force_google_safe_search) {
 400     force_google_safe_search->Init(prefs::kForceSafeSearch, pref_service);
 401     force_google_safe_search->MoveToThread(
 402         BrowserThread::GetMessageLoopProxyForThread(BrowserThread::IO));
 403   }
 404 }
 405
 406 // static
 407 void ChromeNetworkDelegate::AllowAccessToAllFiles() {
 408   g_allow_file_access_ = true;
 409 }
 410
 411 // static
 412 base::Value* ChromeNetworkDelegate::HistoricNetworkStatsInfoToValue() {
 413   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 414   PrefService* prefs = g_browser_process->local_state();
 415   int64 total_received = prefs->GetInt64(prefs::kHttpReceivedContentLength);
 416   int64 total_original = prefs->GetInt64(prefs::kHttpOriginalContentLength);
 417
 418   base::DictionaryValue* dict = new base::DictionaryValue();
 419   // Use strings to avoid overflow.  base::Value only supports 32-bit integers.
 420   dict->SetString("historic_received_content_length",
 421                   base::Int64ToString(total_received));
 422   dict->SetString("historic_original_content_length",
 423                   base::Int64ToString(total_original));
 424   return dict;
 425 }
 426
 427 base::Value* ChromeNetworkDelegate::SessionNetworkStatsInfoToValue() const {
 428   base::DictionaryValue* dict = new base::DictionaryValue();
 429   // Use strings to avoid overflow.  base::Value only supports 32-bit integers.
 430   dict->SetString("session_received_content_length",
 431                   base::Int64ToString(received_content_length_));
 432   dict->SetString("session_original_content_length",
 433                   base::Int64ToString(original_content_length_));
 434   return dict;
 435 }
 436
 437 int ChromeNetworkDelegate::OnBeforeURLRequest(
 438     net::URLRequest* request,
 439     const net::CompletionCallback& callback,
 440     GURL* new_url) {
 441 #if defined(ENABLE_CONFIGURATION_POLICY)
 442   // TODO(joaodasilva): This prevents extensions from seeing URLs that are
 443   // blocked. However, an extension might redirect the request to another URL,
 444   // which is not blocked.
 445   if (url_blacklist_manager_ &&
 446       url_blacklist_manager_->IsRequestBlocked(*request)) {
 447     // URL access blocked by policy.
 448     request->net_log().AddEvent(
 449         net::NetLog::TYPE_CHROME_POLICY_ABORTED_REQUEST,
 450         net::NetLog::StringCallback("url",
 451                                     &request->url().possibly_invalid_spec()));
 452     return net::ERR_BLOCKED_BY_ADMINISTRATOR;
 453   }
 454 #endif
 455
 456   ForwardRequestStatus(REQUEST_STARTED, request, profile_);
 457
 458   if (!enable_referrers_->GetValue())
 459     request->SetReferrer(std::string());
 460   if (enable_do_not_track_ && enable_do_not_track_->GetValue())
 461     request->SetExtraRequestHeaderByName(kDNTHeader, "1", true /* override */);
 462
 463   if (client_hints_) {
 464     request->SetExtraRequestHeaderByName(
 465         ClientHints::kDevicePixelRatioHeader,
 466         client_hints_->GetDevicePixelRatioHeader(), true);
 467   }
 468
 469   bool force_safe_search = force_google_safe_search_ &&
 470                            force_google_safe_search_->GetValue();
 471
 472   net::CompletionCallback wrapped_callback = callback;
 473   if (force_safe_search) {
 474     wrapped_callback = base::Bind(&ForceGoogleSafeSearchCallbackWrapper,
 475                                   callback,
 476                                   base::Unretained(request),
 477                                   base::Unretained(new_url));
 478   }
 479
 480   int rv = ExtensionWebRequestEventRouter::GetInstance()->OnBeforeRequest(
 481       profile_, extension_info_map_.get(), request, wrapped_callback,
 482       new_url);
 483
 484   if (force_safe_search && rv == net::OK && new_url->is_empty())
 485     ForceGoogleSafeSearch(request, new_url);
 486
 487   if (connect_interceptor_)
 488     connect_interceptor_->WitnessURLRequest(request);
 489
 490   return rv;
 491 }
 492
 493 int ChromeNetworkDelegate::OnBeforeSendHeaders(
 494     net::URLRequest* request,
 495     const net::CompletionCallback& callback,
 496     net::HttpRequestHeaders* headers) {
 497   TRACE_EVENT_ASYNC_STEP_PAST0("net", "URLRequest", request, "SendRequest");
 498   return ExtensionWebRequestEventRouter::GetInstance()->OnBeforeSendHeaders(
 499       profile_, extension_info_map_.get(), request, callback, headers);
 500 }
 501
 502 void ChromeNetworkDelegate::OnSendHeaders(
 503     net::URLRequest* request,
 504     const net::HttpRequestHeaders& headers) {
 505   ExtensionWebRequestEventRouter::GetInstance()->OnSendHeaders(
 506       profile_, extension_info_map_.get(), request, headers);
 507 }
 508
 509 int ChromeNetworkDelegate::OnHeadersReceived(
 510     net::URLRequest* request,
 511     const net::CompletionCallback& callback,
 512     const net::HttpResponseHeaders* original_response_headers,
 513     scoped_refptr<net::HttpResponseHeaders>* override_response_headers) {
 514   return ExtensionWebRequestEventRouter::GetInstance()->OnHeadersReceived(
 515       profile_, extension_info_map_.get(), request, callback,
 516       original_response_headers, override_response_headers);
 517 }
 518
 519 void ChromeNetworkDelegate::OnBeforeRedirect(net::URLRequest* request,
 520                                              const GURL& new_location) {
 521   ExtensionWebRequestEventRouter::GetInstance()->OnBeforeRedirect(
 522       profile_, extension_info_map_.get(), request, new_location);
 523 }
 524
 525
 526 void ChromeNetworkDelegate::OnResponseStarted(net::URLRequest* request) {
 527   TRACE_EVENT_ASYNC_STEP_PAST0("net", "URLRequest", request, "ResponseStarted");
 528   ExtensionWebRequestEventRouter::GetInstance()->OnResponseStarted(
 529       profile_, extension_info_map_.get(), request);
 530   ForwardProxyErrors(request, event_router_.get(), profile_);
 531 }
 532
 533 void ChromeNetworkDelegate::OnRawBytesRead(const net::URLRequest& request,
 534                                            int bytes_read) {
 535   TRACE_EVENT_ASYNC_STEP_PAST1("net", "URLRequest", &request, "DidRead",
 536                                "bytes_read", bytes_read);
 537   performance_monitor::PerformanceMonitor::GetInstance()->BytesReadOnIOThread(
 538       request, bytes_read);
 539
 540 #if defined(ENABLE_TASK_MANAGER)
 541   // This is not completely accurate, but as a first approximation ignore
 542   // requests that are served from the cache. See bug 330931 for more info.
 543   if (!request.was_cached())
 544     TaskManager::GetInstance()->model()->NotifyBytesRead(request, bytes_read);
 545 #endif  // defined(ENABLE_TASK_MANAGER)
 546 }
 547
 548 void ChromeNetworkDelegate::OnCompleted(net::URLRequest* request,
 549                                         bool started) {
 550   TRACE_EVENT_ASYNC_END0("net", "URLRequest", request);
 551   if (request->status().status() == net::URLRequestStatus::SUCCESS) {
 552     // For better accuracy, we use the actual bytes read instead of the length
 553     // specified with the Content-Length header, which may be inaccurate,
 554     // or missing, as is the case with chunked encoding.
 555     int64 received_content_length = request->received_response_content_length();
 556
 557 #if defined(OS_ANDROID)
 558     if (precache::PrecacheManager::IsPrecachingEnabled()) {
 559       // Record precache metrics when a fetch is completed successfully, if
 560       // precaching is enabled.
 561       BrowserThread::PostTask(
 562           BrowserThread::UI, FROM_HERE,
 563           base::Bind(&RecordPrecacheStatsOnUIThread, request->url(),
 564                      base::Time::Now(), received_content_length,
 565                      request->was_cached(), profile_));
 566     }
 567 #endif  // defined(OS_ANDROID)
 568
 569     // Only record for http or https urls.
 570     bool is_http = request->url().SchemeIs("http");
 571     bool is_https = request->url().SchemeIs("https");
 572
 573     if (!request->was_cached() &&         // Don't record cached content
 574         received_content_length &&        // Zero-byte responses aren't useful.
 575         (is_http || is_https)) {          // Only record for HTTP or HTTPS urls.
 576       int64 original_content_length =
 577           request->response_info().headers->GetInt64HeaderValue(
 578               "x-original-content-length");
 579       spdyproxy::DataReductionRequestType data_reduction_type =
 580           spdyproxy::GetDataReductionRequestType(request);
 581
 582       base::TimeDelta freshness_lifetime =
 583           request->response_info().headers->GetFreshnessLifetime(
 584               request->response_info().response_time);
 585       int64 adjusted_original_content_length =
 586           spdyproxy::GetAdjustedOriginalContentLength(
 587               data_reduction_type, original_content_length,
 588               received_content_length);
 589       AccumulateContentLength(received_content_length,
 590                               adjusted_original_content_length,
 591                               data_reduction_type);
 592       RecordContentLengthHistograms(received_content_length,
 593                                     original_content_length,
 594                                     freshness_lifetime);
 595       DVLOG(2) << __FUNCTION__
 596           << " received content length: " << received_content_length
 597           << " original content length: " << original_content_length
 598           << " url: " << request->url();
 599     }
 600
 601     bool is_redirect = request->response_headers() &&
 602         net::HttpResponseHeaders::IsRedirectResponseCode(
 603             request->response_headers()->response_code());
 604     if (!is_redirect) {
 605       ExtensionWebRequestEventRouter::GetInstance()->OnCompleted(
 606           profile_, extension_info_map_.get(), request);
 607     }
 608   } else if (request->status().status() == net::URLRequestStatus::FAILED ||
 609              request->status().status() == net::URLRequestStatus::CANCELED) {
 610     ExtensionWebRequestEventRouter::GetInstance()->OnErrorOccurred(
 611             profile_, extension_info_map_.get(), request, started);
 612   } else {
 613     NOTREACHED();
 614   }
 615   ForwardProxyErrors(request, event_router_.get(), profile_);
 616
 617   ForwardRequestStatus(REQUEST_DONE, request, profile_);
 618 }
 619
 620 void ChromeNetworkDelegate::OnURLRequestDestroyed(net::URLRequest* request) {
 621   ExtensionWebRequestEventRouter::GetInstance()->OnURLRequestDestroyed(
 622       profile_, request);
 623 }
 624
 625 void ChromeNetworkDelegate::OnPACScriptError(int line_number,
 626                                              const base::string16& error) {
 627   extensions::ProxyEventRouter::GetInstance()->OnPACScriptError(
 628       event_router_.get(), profile_, line_number, error);
 629 }
 630
 631 net::NetworkDelegate::AuthRequiredResponse
 632 ChromeNetworkDelegate::OnAuthRequired(
 633     net::URLRequest* request,
 634     const net::AuthChallengeInfo& auth_info,
 635     const AuthCallback& callback,
 636     net::AuthCredentials* credentials) {
 637   return ExtensionWebRequestEventRouter::GetInstance()->OnAuthRequired(
 638       profile_, extension_info_map_.get(), request, auth_info,
 639       callback, credentials);
 640 }
 641
 642 bool ChromeNetworkDelegate::OnCanGetCookies(
 643     const net::URLRequest& request,
 644     const net::CookieList& cookie_list) {
 645   // NULL during tests, or when we're running in the system context.
 646   if (!cookie_settings_.get())
 647     return true;
 648
 649   bool allow = cookie_settings_->IsReadingCookieAllowed(
 650       request.url(), request.first_party_for_cookies());
 651
 652   int render_process_id = -1;
 653   int render_frame_id = -1;
 654   if (content::ResourceRequestInfo::GetRenderFrameForRequest(
 655           &request, &render_process_id, &render_frame_id)) {
 656     BrowserThread::PostTask(
 657         BrowserThread::UI, FROM_HERE,
 658         base::Bind(&TabSpecificContentSettings::CookiesRead,
 659                    render_process_id, render_frame_id,
 660                    request.url(), request.first_party_for_cookies(),
 661                    cookie_list, !allow));
 662   }
 663
 664   return allow;
 665 }
 666
 667 bool ChromeNetworkDelegate::OnCanSetCookie(const net::URLRequest& request,
 668                                            const std::string& cookie_line,
 669                                            net::CookieOptions* options) {
 670   // NULL during tests, or when we're running in the system context.
 671   if (!cookie_settings_.get())
 672     return true;
 673
 674   bool allow = cookie_settings_->IsSettingCookieAllowed(
 675       request.url(), request.first_party_for_cookies());
 676
 677   int render_process_id = -1;
 678   int render_frame_id = -1;
 679   if (content::ResourceRequestInfo::GetRenderFrameForRequest(
 680           &request, &render_process_id, &render_frame_id)) {
 681     BrowserThread::PostTask(
 682         BrowserThread::UI, FROM_HERE,
 683         base::Bind(&TabSpecificContentSettings::CookieChanged,
 684                    render_process_id, render_frame_id,
 685                    request.url(), request.first_party_for_cookies(),
 686                    cookie_line, *options, !allow));
 687   }
 688
 689   return allow;
 690 }
 691
 692 bool ChromeNetworkDelegate::OnCanAccessFile(const net::URLRequest& request,
 693                                             const base::FilePath& path) const {
 694   if (g_allow_file_access_)
 695     return true;
 696
 697 #if !defined(OS_CHROMEOS) && !defined(OS_ANDROID)
 698   return true;
 699 #else
 700 #if defined(OS_CHROMEOS)
 701   // If we're running Chrome for ChromeOS on Linux, we want to allow file
 702   // access.
 703   if (!base::SysInfo::IsRunningOnChromeOS() ||
 704       CommandLine::ForCurrentProcess()->HasSwitch(switches::kTestType)) {
 705     return true;
 706   }
 707
 708   // Use a whitelist to only allow access to files residing in the list of
 709   // directories below.
 710   static const char* const kLocalAccessWhiteList[] = {
 711       "/home/chronos/user/Downloads",
 712       "/home/chronos/user/log",
 713       "/media",
 714       "/opt/oem",
 715       "/usr/share/chromeos-assets",
 716       "/tmp",
 717       "/var/log",
 718   };
 719
 720   // The actual location of "/home/chronos/user/Downloads" is the Downloads
 721   // directory under the profile path ("/home/chronos/user' is a hard link to
 722   // current primary logged in profile.) For the support of multi-profile
 723   // sessions, we are switching to use explicit "$PROFILE_PATH/Downloads" path
 724   // and here whitelist such access.
 725   if (!profile_path_.empty()) {
 726     const base::FilePath downloads = profile_path_.AppendASCII("Downloads");
 727     if (downloads == path.StripTrailingSeparators() || downloads.IsParent(path))
 728       return true;
 729   }
 730 #elif defined(OS_ANDROID)
 731   // Access to files in external storage is allowed.
 732   base::FilePath external_storage_path;
 733   PathService::Get(base::DIR_ANDROID_EXTERNAL_STORAGE, &external_storage_path);
 734   if (external_storage_path.IsParent(path))
 735     return true;
 736
 737   // Whitelist of other allowed directories.
 738   static const char* const kLocalAccessWhiteList[] = {
 739       "/sdcard",
 740       "/mnt/sdcard",
 741   };
 742 #endif
 743
 744   for (size_t i = 0; i < arraysize(kLocalAccessWhiteList); ++i) {
 745     const base::FilePath white_listed_path(kLocalAccessWhiteList[i]);
 746     // base::FilePath::operator== should probably handle trailing separators.
 747     if (white_listed_path == path.StripTrailingSeparators() ||
 748         white_listed_path.IsParent(path)) {
 749       return true;
 750     }
 751   }
 752
 753   DVLOG(1) << "File access denied - " << path.value().c_str();
 754   return false;
 755 #endif  // !defined(OS_CHROMEOS) && !defined(OS_ANDROID)
 756 }
 757
 758 bool ChromeNetworkDelegate::OnCanThrottleRequest(
 759     const net::URLRequest& request) const {
 760   if (g_never_throttle_requests_) {
 761     return false;
 762   }
 763
 764   return request.first_party_for_cookies().scheme() ==
 765       extensions::kExtensionScheme;
 766 }
 767
 768 bool ChromeNetworkDelegate::OnCanEnablePrivacyMode(
 769     const GURL& url,
 770     const GURL& first_party_for_cookies) const {
 771   // NULL during tests, or when we're running in the system context.
 772   if (!cookie_settings_.get())
 773     return false;
 774
 775   bool reading_cookie_allowed = cookie_settings_->IsReadingCookieAllowed(
 776       url, first_party_for_cookies);
 777   bool setting_cookie_allowed = cookie_settings_->IsSettingCookieAllowed(
 778       url, first_party_for_cookies);
 779   bool privacy_mode = !(reading_cookie_allowed && setting_cookie_allowed);
 780   return privacy_mode;
 781 }
 782
 783 int ChromeNetworkDelegate::OnBeforeSocketStreamConnect(
 784     net::SocketStream* socket,
 785     const net::CompletionCallback& callback) {
 786 #if defined(ENABLE_CONFIGURATION_POLICY)
 787   if (url_blacklist_manager_ &&
 788       url_blacklist_manager_->IsURLBlocked(socket->url())) {
 789     // URL access blocked by policy.
 790     socket->net_log()->AddEvent(
 791         net::NetLog::TYPE_CHROME_POLICY_ABORTED_REQUEST,
 792         net::NetLog::StringCallback("url",
 793                                     &socket->url().possibly_invalid_spec()));
 794     return net::ERR_BLOCKED_BY_ADMINISTRATOR;
 795   }
 796 #endif
 797   return net::OK;
 798 }
 799
 800 void ChromeNetworkDelegate::AccumulateContentLength(
 801     int64 received_content_length,
 802     int64 original_content_length,
 803     spdyproxy::DataReductionRequestType data_reduction_type) {
 804   DCHECK_GE(received_content_length, 0);
 805   DCHECK_GE(original_content_length, 0);
 806   StoreAccumulatedContentLength(received_content_length,
 807                                 original_content_length,
 808                                 data_reduction_type,
 809                                 reinterpret_cast<Profile*>(profile_));
 810   received_content_length_ += received_content_length;
 811   original_content_length_ += original_content_length;
 812 }