net/proxy/proxy_config_service_win.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 "net/proxy/proxy_config_service_win.h"
   6
   7 #include <windows.h>
   8 #include <winhttp.h>
   9
  10 #include "base/logging.h"
  11 #include "base/memory/scoped_ptr.h"
  12 #include "base/stl_util.h"
  13 #include "base/strings/string_util.h"
  14 #include "base/strings/string_tokenizer.h"
  15 #include "base/threading/thread_restrictions.h"
  16 #include "base/win/registry.h"
  17 #include "net/base/net_errors.h"
  18 #include "net/proxy/proxy_config.h"
  19
  20 #pragma comment(lib, "winhttp.lib")
  21
  22 namespace net {
  23
  24 namespace {
  25
  26 const int kPollIntervalSec = 10;
  27
  28 void FreeIEConfig(WINHTTP_CURRENT_USER_IE_PROXY_CONFIG* ie_config) {
  29   if (ie_config->lpszAutoConfigUrl)
  30     GlobalFree(ie_config->lpszAutoConfigUrl);
  31   if (ie_config->lpszProxy)
  32     GlobalFree(ie_config->lpszProxy);
  33   if (ie_config->lpszProxyBypass)
  34     GlobalFree(ie_config->lpszProxyBypass);
  35 }
  36
  37 }  // namespace
  38
  39 // RegKey and ObjectWatcher pair.
  40 class ProxyConfigServiceWin::KeyEntry {
  41  public:
  42   bool StartWatching(base::win::ObjectWatcher::Delegate* delegate) {
  43     // Try to create a watch event for the registry key (which watches the
  44     // sibling tree as well).
  45     if (key_.StartWatching() != ERROR_SUCCESS)
  46       return false;
  47
  48     // Now setup an ObjectWatcher for this event, so we get OnObjectSignaled()
  49     // invoked on this message loop once it is signalled.
  50     if (!watcher_.StartWatching(key_.watch_event(), delegate))
  51       return false;
  52
  53     return true;
  54   }
  55
  56   bool CreateRegKey(HKEY rootkey, const wchar_t* subkey) {
  57     return key_.Create(rootkey, subkey, KEY_NOTIFY) == ERROR_SUCCESS;
  58   }
  59
  60   HANDLE watch_event() const {
  61     return key_.watch_event();
  62   }
  63
  64  private:
  65   base::win::RegKey key_;
  66   base::win::ObjectWatcher watcher_;
  67 };
  68
  69 ProxyConfigServiceWin::ProxyConfigServiceWin()
  70     : PollingProxyConfigService(
  71           base::TimeDelta::FromSeconds(kPollIntervalSec),
  72           &ProxyConfigServiceWin::GetCurrentProxyConfig) {
  73 }
  74
  75 ProxyConfigServiceWin::~ProxyConfigServiceWin() {
  76   // The registry functions below will end up going to disk.  Do this on another
  77   // thread to avoid slowing the IO thread.  http://crbug.com/61453
  78   base::ThreadRestrictions::ScopedAllowIO allow_io;
  79   STLDeleteElements(&keys_to_watch_);
  80 }
  81
  82 void ProxyConfigServiceWin::AddObserver(Observer* observer) {
  83   // Lazily-initialize our registry watcher.
  84   StartWatchingRegistryForChanges();
  85
  86   // Let the super-class do its work now.
  87   PollingProxyConfigService::AddObserver(observer);
  88 }
  89
  90 void ProxyConfigServiceWin::StartWatchingRegistryForChanges() {
  91   if (!keys_to_watch_.empty())
  92     return;  // Already initialized.
  93
  94   // The registry functions below will end up going to disk.  Do this on another
  95   // thread to avoid slowing the IO thread.  http://crbug.com/61453
  96   base::ThreadRestrictions::ScopedAllowIO allow_io;
  97
  98   // There are a number of different places where proxy settings can live
  99   // in the registry. In some cases it appears in a binary value, in other
 100   // cases string values. Furthermore winhttp and wininet appear to have
 101   // separate stores, and proxy settings can be configured per-machine
 102   // or per-user.
 103   //
 104   // This function is probably not exhaustive in the registry locations it
 105   // watches for changes, however it should catch the majority of the
 106   // cases. In case we have missed some less common triggers (likely), we
 107   // will catch them during the periodic (10 second) polling, so things
 108   // will recover.
 109
 110   AddKeyToWatchList(
 111       HKEY_CURRENT_USER,
 112       L"Software\\Microsoft\\Windows\\CurrentVersion\\Internet Settings");
 113
 114   AddKeyToWatchList(
 115       HKEY_LOCAL_MACHINE,
 116       L"Software\\Microsoft\\Windows\\CurrentVersion\\Internet Settings");
 117
 118   AddKeyToWatchList(
 119       HKEY_LOCAL_MACHINE,
 120       L"SOFTWARE\\Policies\\Microsoft\\Windows\\CurrentVersion\\"
 121       L"Internet Settings");
 122 }
 123
 124 bool ProxyConfigServiceWin::AddKeyToWatchList(HKEY rootkey,
 125                                               const wchar_t* subkey) {
 126   scoped_ptr<KeyEntry> entry(new KeyEntry);
 127   if (!entry->CreateRegKey(rootkey, subkey))
 128     return false;
 129
 130   if (!entry->StartWatching(this))
 131     return false;
 132
 133   keys_to_watch_.push_back(entry.release());
 134   return true;
 135 }
 136
 137 void ProxyConfigServiceWin::OnObjectSignaled(HANDLE object) {
 138   // Figure out which registry key signalled this change.
 139   KeyEntryList::iterator it;
 140   for (it = keys_to_watch_.begin(); it != keys_to_watch_.end(); ++it) {
 141     if ((*it)->watch_event() == object)
 142       break;
 143   }
 144
 145   DCHECK(it != keys_to_watch_.end());
 146
 147   // Keep watching the registry key.
 148   if (!(*it)->StartWatching(this))
 149     keys_to_watch_.erase(it);
 150
 151   // Have the PollingProxyConfigService test for changes.
 152   CheckForChangesNow();
 153 }
 154
 155 // static
 156 void ProxyConfigServiceWin::GetCurrentProxyConfig(ProxyConfig* config) {
 157   WINHTTP_CURRENT_USER_IE_PROXY_CONFIG ie_config = {0};
 158   if (!WinHttpGetIEProxyConfigForCurrentUser(&ie_config)) {
 159     LOG(ERROR) << "WinHttpGetIEProxyConfigForCurrentUser failed: " <<
 160         GetLastError();
 161     *config = ProxyConfig::CreateDirect();
 162     config->set_source(PROXY_CONFIG_SOURCE_SYSTEM_FAILED);
 163     return;
 164   }
 165   SetFromIEConfig(config, ie_config);
 166   FreeIEConfig(&ie_config);
 167 }
 168
 169 // static
 170 void ProxyConfigServiceWin::SetFromIEConfig(
 171     ProxyConfig* config,
 172     const WINHTTP_CURRENT_USER_IE_PROXY_CONFIG& ie_config) {
 173   if (ie_config.fAutoDetect)
 174     config->set_auto_detect(true);
 175   if (ie_config.lpszProxy) {
 176     // lpszProxy may be a single proxy, or a proxy per scheme. The format
 177     // is compatible with ProxyConfig::ProxyRules's string format.
 178     config->proxy_rules().ParseFromString(WideToASCII(ie_config.lpszProxy));
 179   }
 180   if (ie_config.lpszProxyBypass) {
 181     std::string proxy_bypass = WideToASCII(ie_config.lpszProxyBypass);
 182
 183     base::StringTokenizer proxy_server_bypass_list(proxy_bypass, ";, \t\n\r");
 184     while (proxy_server_bypass_list.GetNext()) {
 185       std::string bypass_url_domain = proxy_server_bypass_list.token();
 186       config->proxy_rules().bypass_rules.AddRuleFromString(bypass_url_domain);
 187     }
 188   }
 189   if (ie_config.lpszAutoConfigUrl)
 190     config->set_pac_url(GURL(ie_config.lpszAutoConfigUrl));
 191   config->set_source(PROXY_CONFIG_SOURCE_SYSTEM);
 192 }
 193
 194 }  // namespace net