1 // Copyright (c) 2011 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/intranet_redirect_detector.h" 6 7 #include "base/command_line.h" 8 #include "base/rand_util.h" 9 #include "base/stl_util-inl.h" 10 #include "base/utf_string_conversions.h" 11 #include "chrome/browser/browser_process.h" 12 #include "chrome/browser/prefs/pref_service.h" 13 #include "chrome/common/chrome_switches.h" 14 #include "chrome/common/pref_names.h" 15 #include "content/common/notification_service.h" 16 #include "net/base/load_flags.h" 17 #include "net/base/net_errors.h" 18 #include "net/base/registry_controlled_domain.h" 19 #include "net/url_request/url_request_context_getter.h" 20 #include "net/url_request/url_request_status.h" 21 22 const size_t IntranetRedirectDetector::kNumCharsInHostnames = 10; 23 24 IntranetRedirectDetector::IntranetRedirectDetector() 25 : redirect_origin_(g_browser_process->local_state()->GetString( 26 prefs::kLastKnownIntranetRedirectOrigin)), 27 ALLOW_THIS_IN_INITIALIZER_LIST(fetcher_factory_(this)), 28 in_sleep_(true) { 29 // Because this function can be called during startup, when kicking off a URL 30 // fetch can eat up 20 ms of time, we delay seven seconds, which is hopefully 31 // long enough to be after startup, but still get results back quickly. 32 // Ideally, instead of this timer, we'd do something like "check if the 33 // browser is starting up, and if so, come back later", but there is currently 34 // no function to do this. 35 static const int kStartFetchDelayMS = 7000; 36 MessageLoop::current()->PostDelayedTask(FROM_HERE, 37 fetcher_factory_.NewRunnableMethod( 38 &IntranetRedirectDetector::FinishSleep), 39 kStartFetchDelayMS); 40 41 net::NetworkChangeNotifier::AddIPAddressObserver(this); 42 } 43 44 IntranetRedirectDetector::~IntranetRedirectDetector() { 45 net::NetworkChangeNotifier::RemoveIPAddressObserver(this); 46 STLDeleteElements(&fetchers_); 47 } 48 49 // static 50 GURL IntranetRedirectDetector::RedirectOrigin() { 51 const IntranetRedirectDetector* const detector = 52 g_browser_process->intranet_redirect_detector(); 53 return detector ? detector->redirect_origin_ : GURL(); 54 } 55 56 // static 57 void IntranetRedirectDetector::RegisterPrefs(PrefService* prefs) { 58 prefs->RegisterStringPref(prefs::kLastKnownIntranetRedirectOrigin, 59 std::string()); 60 } 61 62 void IntranetRedirectDetector::FinishSleep() { 63 in_sleep_ = false; 64 65 // If another fetch operation is still running, cancel it. 66 STLDeleteElements(&fetchers_); 67 resulting_origins_.clear(); 68 69 // The detector is not needed in Chrome Frame since we have no omnibox there. 70 const CommandLine* cmd_line = CommandLine::ForCurrentProcess(); 71 if (cmd_line->HasSwitch(switches::kDisableBackgroundNetworking) || 72 cmd_line->HasSwitch(switches::kChromeFrame)) 73 return; 74 75 DCHECK(fetchers_.empty() && resulting_origins_.empty()); 76 77 // Start three fetchers on random hostnames. 78 for (size_t i = 0; i < 3; ++i) { 79 std::string url_string("http://"); 80 for (size_t j = 0; j < kNumCharsInHostnames; ++j) 81 url_string += ('a' + base::RandInt(0, 'z' - 'a')); 82 GURL random_url(url_string + '/'); 83 URLFetcher* fetcher = new URLFetcher(random_url, URLFetcher::HEAD, this); 84 // We don't want these fetches to affect existing state in the profile. 85 fetcher->set_load_flags(net::LOAD_DISABLE_CACHE | 86 net::LOAD_DO_NOT_SAVE_COOKIES); 87 fetcher->set_request_context(g_browser_process->system_request_context()); 88 fetcher->Start(); 89 fetchers_.insert(fetcher); 90 } 91 } 92 93 void IntranetRedirectDetector::OnURLFetchComplete( 94 const URLFetcher* source, 95 const GURL& url, 96 const net::URLRequestStatus& status, 97 int response_code, 98 const ResponseCookies& cookies, 99 const std::string& data) { 100 // Delete the fetcher on this function's exit. 101 Fetchers::iterator fetcher = fetchers_.find(const_cast<URLFetcher*>(source)); 102 DCHECK(fetcher != fetchers_.end()); 103 scoped_ptr<URLFetcher> clean_up_fetcher(*fetcher); 104 fetchers_.erase(fetcher); 105 106 // If any two fetches result in the same domain/host, we set the redirect 107 // origin to that; otherwise we set it to nothing. 108 if (!status.is_success() || (response_code != 200)) { 109 if ((resulting_origins_.empty()) || 110 ((resulting_origins_.size() == 1) && 111 resulting_origins_.front().is_valid())) { 112 resulting_origins_.push_back(GURL()); 113 return; 114 } 115 redirect_origin_ = GURL(); 116 } else { 117 DCHECK(url.is_valid()); 118 GURL origin(url.GetOrigin()); 119 if (resulting_origins_.empty()) { 120 resulting_origins_.push_back(origin); 121 return; 122 } 123 if (net::RegistryControlledDomainService::SameDomainOrHost( 124 resulting_origins_.front(), origin)) { 125 redirect_origin_ = origin; 126 if (!fetchers_.empty()) { 127 // Cancel remaining fetch, we don't need it. 128 DCHECK(fetchers_.size() == 1); 129 delete (*fetchers_.begin()); 130 fetchers_.clear(); 131 } 132 } 133 if (resulting_origins_.size() == 1) { 134 resulting_origins_.push_back(origin); 135 return; 136 } 137 DCHECK(resulting_origins_.size() == 2); 138 redirect_origin_ = net::RegistryControlledDomainService::SameDomainOrHost( 139 resulting_origins_.back(), origin) ? origin : GURL(); 140 } 141 142 g_browser_process->local_state()->SetString( 143 prefs::kLastKnownIntranetRedirectOrigin, redirect_origin_.is_valid() ? 144 redirect_origin_.spec() : std::string()); 145 } 146 147 void IntranetRedirectDetector::OnIPAddressChanged() { 148 // If a request is already scheduled, do not scheduled yet another one. 149 if (in_sleep_) 150 return; 151 152 // Since presumably many programs open connections after network changes, 153 // delay this a little bit. 154 in_sleep_ = true; 155 static const int kNetworkSwitchDelayMS = 1000; 156 MessageLoop::current()->PostDelayedTask(FROM_HERE, 157 fetcher_factory_.NewRunnableMethod( 158 &IntranetRedirectDetector::FinishSleep), 159 kNetworkSwitchDelayMS); 160 } 161 162 IntranetRedirectHostResolverProc::IntranetRedirectHostResolverProc( 163 net::HostResolverProc* previous) 164 : net::HostResolverProc(previous) { 165 } 166 167 int IntranetRedirectHostResolverProc::Resolve( 168 const std::string& host, 169 net::AddressFamily address_family, 170 net::HostResolverFlags host_resolver_flags, 171 net::AddressList* addrlist, 172 int* os_error) { 173 // We'd love to just ask the IntranetRedirectDetector, but we may not be on 174 // the same thread. So just use the heuristic that any all-lowercase a-z 175 // hostname with the right number of characters is likely from the detector 176 // (and thus should be blocked). 177 return ((host.length() == IntranetRedirectDetector::kNumCharsInHostnames) && 178 (host.find_first_not_of("abcdefghijklmnopqrstuvwxyz") == 179 std::string::npos)) ? 180 net::ERR_NAME_NOT_RESOLVED : 181 ResolveUsingPrevious(host, address_family, host_resolver_flags, addrlist, 182 os_error); 183 } 184