Implement 'Do Not Track' header

chrome/browser/net/chrome_network_delegate.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/net/chrome_network_delegate.h"
 
 #include "base/logging.h"
 #include "base/base_paths.h"
 #include "base/path_service.h"
 #include "chrome/browser/api/prefs/pref_member.h"
@@ skipping 51 matching lines @@
 #else
 bool ChromeNetworkDelegate::g_allow_file_access_ = true;
 #endif
 
 // This remains false unless the --disable-extensions-http-throttling
 // flag is passed to the browser.
 bool ChromeNetworkDelegate::g_never_throttle_requests_ = false;
 
 namespace {
 
+const char kDNTHeader[] = "DNT";
+
 // If the |request| failed due to problems with a proxy, forward the error to
 // the proxy extension API.
 void ForwardProxyErrors(net::URLRequest* request,
                         extensions::EventRouterForwarder* event_router,
                         void* profile) {
   if (request->status().status() == net::URLRequestStatus::FAILED) {
     switch (request->status().error()) {
       case net::ERR_PROXY_AUTH_UNSUPPORTED:
       case net::ERR_PROXY_CONNECTION_FAILED:
       case net::ERR_TUNNEL_CONNECTION_FAILED:
@@ skipping 54 matching lines @@
 }  // namespace
 
 ChromeNetworkDelegate::ChromeNetworkDelegate(
     extensions::EventRouterForwarder* event_router,
     ExtensionInfoMap* extension_info_map,
     const policy::URLBlacklistManager* url_blacklist_manager,
     const ManagedModeURLFilter* managed_mode_url_filter,
     void* profile,
     CookieSettings* cookie_settings,
     BooleanPrefMember* enable_referrers,
+    BooleanPrefMember* enable_do_not_track,
     chrome_browser_net::LoadTimeStats* load_time_stats)
     : event_router_(event_router),
       profile_(profile),
       cookie_settings_(cookie_settings),
       extension_info_map_(extension_info_map),
       enable_referrers_(enable_referrers),
+      enable_do_not_track_(enable_do_not_track),
       url_blacklist_manager_(url_blacklist_manager),
       managed_mode_url_filter_(managed_mode_url_filter),
       load_time_stats_(load_time_stats) {
   DCHECK(event_router);
   DCHECK(enable_referrers);
   DCHECK(!profile || cookie_settings);
 }
 
 ChromeNetworkDelegate::~ChromeNetworkDelegate() {}
 
 // static
 void ChromeNetworkDelegate::NeverThrottleRequests() {
   g_never_throttle_requests_ = true;
 }
 
 // static
-void ChromeNetworkDelegate::InitializeReferrersEnabled(
+void ChromeNetworkDelegate::InitializePrefsOnUIThread(
     BooleanPrefMember* enable_referrers,
+    BooleanPrefMember* enable_do_not_track,
     PrefService* pref_service) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   enable_referrers->Init(prefs::kEnableReferrers, pref_service, NULL);
   enable_referrers->MoveToThread(BrowserThread::IO);
+  if (enable_do_not_track) {
+    enable_do_not_track->Init(prefs::kEnableDoNotTrack, pref_service, NULL);
+    enable_do_not_track->MoveToThread(BrowserThread::IO);
+  }
 }
 
 // static
 void ChromeNetworkDelegate::AllowAccessToAllFiles() {
   g_allow_file_access_ = true;
 }
 
 int ChromeNetworkDelegate::OnBeforeURLRequest(
     net::URLRequest* request,
     const net::CompletionCallback& callback,
@@ skipping 18 matching lines @@
       !managed_mode_url_filter_->IsURLWhitelisted(request->url())) {
     // Block for now.
     return net::ERR_NETWORK_ACCESS_DENIED;
   }
 #endif
 
   ForwardRequestStatus(REQUEST_STARTED, request, profile_);
 
   if (!enable_referrers_->GetValue())
     request->set_referrer(std::string());
+  if (enable_do_not_track_ && enable_do_not_track_->GetValue())
+    request->SetExtraRequestHeaderByName(kDNTHeader, "1", true /* override */);
   return ExtensionWebRequestEventRouter::GetInstance()->OnBeforeRequest(
       profile_, extension_info_map_.get(), request, callback, new_url);
 }
 
 int ChromeNetworkDelegate::OnBeforeSendHeaders(
     net::URLRequest* request,
     const net::CompletionCallback& callback,
     net::HttpRequestHeaders* headers) {
   return ExtensionWebRequestEventRouter::GetInstance()->OnBeforeSendHeaders(
       profile_, extension_info_map_.get(), request, callback, headers);
@@ skipping 214 matching lines @@
 #endif
   return net::OK;
 }
 
 void ChromeNetworkDelegate::OnRequestWaitStateChange(
     const net::URLRequest& request,
     RequestWaitState state) {
   if (load_time_stats_)
     load_time_stats_->OnRequestWaitStateChange(request, state);
 }