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/strings/utf_string_conversions.h"
  16 #include "base/threading/thread_restrictions.h"
  17 #include "base/win/registry.h"
  18 #include "net/base/net_errors.h"
  19 #include "net/proxy/proxy_config.h"
  20
  21 #pragma comment(lib, "winhttp.lib")
  22
  23 namespace net {
  24
  25 namespace {
  26
  27 const int kPollIntervalSec = 10;
  28
  29 void FreeIEConfig(WINHTTP_CURRENT_USER_IE_PROXY_CONFIG* ie_config) {
  30   if (ie_config->lpszAutoConfigUrl)
  31     GlobalFree(ie_config->lpszAutoConfigUrl);
  32   if (ie_config->lpszProxy)
  33     GlobalFree(ie_config->lpszProxy);
  34   if (ie_config->lpszProxyBypass)
  35     GlobalFree(ie_config->lpszProxyBypass);
  36 }
  37
  38 }  // namespace
  39
  40 // RegKey and ObjectWatcher pair.
  41 class ProxyConfigServiceWin::KeyEntry {
  42  public:
  43   bool StartWatching(base::win::ObjectWatcher::Delegate* delegate) {
  44     // Try to create a watch event for the registry key (which watches the
  45     // sibling tree as well).
  46     if (key_.StartWatching() != ERROR_SUCCESS)
  47       return false;
  48
  49     // Now setup an ObjectWatcher for this event, so we get OnObjectSignaled()
  50     // invoked on this message loop once it is signalled.
  51     if (!watcher_.StartWatching(key_.watch_event(), delegate))
  52       return false;
  53
  54     return true;
  55   }
  56
  57   bool CreateRegKey(HKEY rootkey, const wchar_t* subkey) {
  58     return key_.Create(rootkey, subkey, KEY_NOTIFY) == ERROR_SUCCESS;
  59   }
  60
  61   HANDLE watch_event() const {
  62     return key_.watch_event();
  63   }
  64
  65  private:
  66   base::win::RegKey key_;
  67   base::win::ObjectWatcher watcher_;
  68 };
  69
  70 ProxyConfigServiceWin::ProxyConfigServiceWin()
  71     : PollingProxyConfigService(
  72           base::TimeDelta::FromSeconds(kPollIntervalSec),
  73           &ProxyConfigServiceWin::GetCurrentProxyConfig) {
  74 }
  75
  76 ProxyConfigServiceWin::~ProxyConfigServiceWin() {
  77   // The registry functions below will end up going to disk.  Do this on another
  78   // thread to avoid slowing the IO thread.  http://crbug.com/61453
  79   base::ThreadRestrictions::ScopedAllowIO allow_io;
  80   STLDeleteElements(&keys_to_watch_);
  81 }
  82
  83 void ProxyConfigServiceWin::AddObserver(Observer* observer) {
  84   // Lazily-initialize our registry watcher.
  85   StartWatchingRegistryForChanges();
  86
  87   // Let the super-class do its work now.
  88   PollingProxyConfigService::AddObserver(observer);
  89 }
  90
  91 void ProxyConfigServiceWin::StartWatchingRegistryForChanges() {
  92   if (!keys_to_watch_.empty())
  93     return;  // Already initialized.
  94
  95   // The registry functions below will end up going to disk.  Do this on another
  96   // thread to avoid slowing the IO thread.  http://crbug.com/61453
  97   base::ThreadRestrictions::ScopedAllowIO allow_io;
  98
  99   // There are a number of different places where proxy settings can live
 100   // in the registry. In some cases it appears in a binary value, in other
 101   // cases string values. Furthermore winhttp and wininet appear to have
 102   // separate stores, and proxy settings can be configured per-machine
 103   // or per-user.
 104   //
 105   // This function is probably not exhaustive in the registry locations it
 106   // watches for changes, however it should catch the majority of the
 107   // cases. In case we have missed some less common triggers (likely), we
 108   // will catch them during the periodic (10 second) polling, so things
 109   // will recover.
 110
 111   AddKeyToWatchList(
 112       HKEY_CURRENT_USER,
 113       L"Software\\Microsoft\\Windows\\CurrentVersion\\Internet Settings");
 114
 115   AddKeyToWatchList(
 116       HKEY_LOCAL_MACHINE,
 117       L"Software\\Microsoft\\Windows\\CurrentVersion\\Internet Settings");
 118
 119   AddKeyToWatchList(
 120       HKEY_LOCAL_MACHINE,
 121       L"SOFTWARE\\Policies\\Microsoft\\Windows\\CurrentVersion\\"
 122       L"Internet Settings");
 123 }
 124
 125 bool ProxyConfigServiceWin::AddKeyToWatchList(HKEY rootkey,
 126                                               const wchar_t* subkey) {
 127   scoped_ptr<KeyEntry> entry(new KeyEntry);
 128   if (!entry->CreateRegKey(rootkey, subkey))
 129     return false;
 130
 131   if (!entry->StartWatching(this))
 132     return false;
 133
 134   keys_to_watch_.push_back(entry.release());
 135   return true;
 136 }
 137
 138 void ProxyConfigServiceWin::OnObjectSignaled(HANDLE object) {
 139   // Figure out which registry key signalled this change.
 140   KeyEntryList::iterator it;
 141   for (it = keys_to_watch_.begin(); it != keys_to_watch_.end(); ++it) {
 142     if ((*it)->watch_event() == object)
 143       break;
 144   }
 145
 146   DCHECK(it != keys_to_watch_.end());
 147
 148   // Keep watching the registry key.
 149   if (!(*it)->StartWatching(this))
 150     keys_to_watch_.erase(it);
 151
 152   // Have the PollingProxyConfigService test for changes.
 153   CheckForChangesNow();
 154 }
 155
 156 // static
 157 void ProxyConfigServiceWin::GetCurrentProxyConfig(ProxyConfig* config) {
 158   WINHTTP_CURRENT_USER_IE_PROXY_CONFIG ie_config = {0};
 159   if (!WinHttpGetIEProxyConfigForCurrentUser(&ie_config)) {
 160     LOG(ERROR) << "WinHttpGetIEProxyConfigForCurrentUser failed: " <<
 161         GetLastError();
 162     *config = ProxyConfig::CreateDirect();
 163     config->set_source(PROXY_CONFIG_SOURCE_SYSTEM_FAILED);
 164     return;
 165   }
 166   SetFromIEConfig(config, ie_config);
 167   FreeIEConfig(&ie_config);
 168 }
 169
 170 // static
 171 void ProxyConfigServiceWin::SetFromIEConfig(
 172     ProxyConfig* config,
 173     const WINHTTP_CURRENT_USER_IE_PROXY_CONFIG& ie_config) {
 174   if (ie_config.fAutoDetect)
 175     config->set_auto_detect(true);
 176   if (ie_config.lpszProxy) {
 177     // lpszProxy may be a single proxy, or a proxy per scheme. The format
 178     // is compatible with ProxyConfig::ProxyRules's string format.
 179     config->proxy_rules().ParseFromString(
 180         base::UTF16ToASCII(ie_config.lpszProxy));
 181   }
 182   if (ie_config.lpszProxyBypass) {
 183     std::string proxy_bypass = base::UTF16ToASCII(ie_config.lpszProxyBypass);
 184
 185     base::StringTokenizer proxy_server_bypass_list(proxy_bypass, ";, \t\n\r");
 186     while (proxy_server_bypass_list.GetNext()) {
 187       std::string bypass_url_domain = proxy_server_bypass_list.token();
 188       config->proxy_rules().bypass_rules.AddRuleFromString(bypass_url_domain);
 189     }
 190   }
 191   if (ie_config.lpszAutoConfigUrl)
 192     config->set_pac_url(GURL(ie_config.lpszAutoConfigUrl));
 193   config->set_source(PROXY_CONFIG_SOURCE_SYSTEM);
 194 }
 195
 196 }  // namespace net