1 // Copyright 2012 The Chromium Authors
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_resolution/win/proxy_config_service_win.h"
6
7 #include <windows.h>
8
9 #include <winhttp.h>
10
11 #include "base/functional/bind.h"
12 #include "base/functional/callback.h"
13 #include "base/functional/callback_helpers.h"
14 #include "base/logging.h"
15 #include "base/ranges/algorithm.h"
16 #include "base/strings/string_tokenizer.h"
17 #include "base/strings/string_util.h"
18 #include "base/strings/utf_string_conversions.h"
19 #include "base/threading/thread_restrictions.h"
20 #include "base/win/registry.h"
21 #include "base/win/scoped_handle.h"
22 #include "net/base/net_errors.h"
23
24 namespace net {
25
26 namespace {
27
28 const int kPollIntervalSec = 10;
29
FreeIEConfig(WINHTTP_CURRENT_USER_IE_PROXY_CONFIG * ie_config)30 void FreeIEConfig(WINHTTP_CURRENT_USER_IE_PROXY_CONFIG* ie_config) {
31 if (ie_config->lpszAutoConfigUrl)
32 GlobalFree(ie_config->lpszAutoConfigUrl);
33 if (ie_config->lpszProxy)
34 GlobalFree(ie_config->lpszProxy);
35 if (ie_config->lpszProxyBypass)
36 GlobalFree(ie_config->lpszProxyBypass);
37 }
38
39 } // namespace
40
ProxyConfigServiceWin(const NetworkTrafficAnnotationTag & traffic_annotation)41 ProxyConfigServiceWin::ProxyConfigServiceWin(
42 const NetworkTrafficAnnotationTag& traffic_annotation)
43 : PollingProxyConfigService(base::Seconds(kPollIntervalSec),
44 &ProxyConfigServiceWin::GetCurrentProxyConfig,
45 traffic_annotation) {
46 NetworkChangeNotifier::AddNetworkChangeObserver(this);
47 }
48
~ProxyConfigServiceWin()49 ProxyConfigServiceWin::~ProxyConfigServiceWin() {
50 NetworkChangeNotifier::RemoveNetworkChangeObserver(this);
51 // The registry functions below will end up going to disk. TODO: Do this on
52 // another thread to avoid slowing the current thread. http://crbug.com/61453
53 base::ScopedAllowBlocking scoped_allow_blocking;
54 keys_to_watch_.clear();
55 }
56
AddObserver(Observer * observer)57 void ProxyConfigServiceWin::AddObserver(Observer* observer) {
58 // Lazily-initialize our registry watcher.
59 StartWatchingRegistryForChanges();
60
61 // Let the super-class do its work now.
62 PollingProxyConfigService::AddObserver(observer);
63 }
64
OnNetworkChanged(NetworkChangeNotifier::ConnectionType type)65 void ProxyConfigServiceWin::OnNetworkChanged(
66 NetworkChangeNotifier::ConnectionType type) {
67 // Proxy settings on Windows may change when the active connection changes.
68 // For instance, after connecting to a VPN, the proxy settings for the active
69 // connection will be that for the VPN. (And ProxyConfigService only reports
70 // proxy settings for the default connection).
71
72 // This is conditioned on CONNECTION_NONE to avoid duplicating work, as
73 // NetworkChangeNotifier additionally sends it preceding completion.
74 // See https://crbug.com/1071901.
75 if (type == NetworkChangeNotifier::CONNECTION_NONE)
76 CheckForChangesNow();
77 }
78
StartWatchingRegistryForChanges()79 void ProxyConfigServiceWin::StartWatchingRegistryForChanges() {
80 if (!keys_to_watch_.empty())
81 return; // Already initialized.
82
83 // The registry functions below will end up going to disk. Do this on another
84 // thread to avoid slowing the current thread. http://crbug.com/61453
85 base::ScopedAllowBlocking scoped_allow_blocking;
86
87 // There are a number of different places where proxy settings can live
88 // in the registry. In some cases it appears in a binary value, in other
89 // cases string values. Furthermore winhttp and wininet appear to have
90 // separate stores, and proxy settings can be configured per-machine
91 // or per-user.
92 //
93 // This function is probably not exhaustive in the registry locations it
94 // watches for changes, however it should catch the majority of the
95 // cases. In case we have missed some less common triggers (likely), we
96 // will catch them during the periodic (10 second) polling, so things
97 // will recover.
98
99 AddKeyToWatchList(
100 HKEY_CURRENT_USER,
101 L"Software\\Microsoft\\Windows\\CurrentVersion\\Internet Settings");
102
103 AddKeyToWatchList(
104 HKEY_LOCAL_MACHINE,
105 L"Software\\Microsoft\\Windows\\CurrentVersion\\Internet Settings");
106
107 AddKeyToWatchList(HKEY_LOCAL_MACHINE,
108 L"SOFTWARE\\Policies\\Microsoft\\Windows\\CurrentVersion\\"
109 L"Internet Settings");
110 }
111
AddKeyToWatchList(HKEY rootkey,const wchar_t * subkey)112 bool ProxyConfigServiceWin::AddKeyToWatchList(HKEY rootkey,
113 const wchar_t* subkey) {
114 std::unique_ptr<base::win::RegKey> key =
115 std::make_unique<base::win::RegKey>();
116 if (key->Create(rootkey, subkey, KEY_NOTIFY) != ERROR_SUCCESS)
117 return false;
118
119 if (!key->StartWatching(base::BindOnce(
120 &ProxyConfigServiceWin::OnObjectSignaled, base::Unretained(this),
121 base::Unretained(key.get())))) {
122 return false;
123 }
124
125 keys_to_watch_.push_back(std::move(key));
126 return true;
127 }
128
OnObjectSignaled(base::win::RegKey * key)129 void ProxyConfigServiceWin::OnObjectSignaled(base::win::RegKey* key) {
130 // Figure out which registry key signalled this change.
131 auto it = base::ranges::find(keys_to_watch_, key,
132 &std::unique_ptr<base::win::RegKey>::get);
133 DCHECK(it != keys_to_watch_.end());
134
135 // Keep watching the registry key.
136 if (!key->StartWatching(
137 base::BindOnce(&ProxyConfigServiceWin::OnObjectSignaled,
138 base::Unretained(this), base::Unretained(key)))) {
139 keys_to_watch_.erase(it);
140 }
141
142 // Have the PollingProxyConfigService test for changes.
143 CheckForChangesNow();
144 }
145
146 // static
GetCurrentProxyConfig(const NetworkTrafficAnnotationTag traffic_annotation,ProxyConfigWithAnnotation * config)147 void ProxyConfigServiceWin::GetCurrentProxyConfig(
148 const NetworkTrafficAnnotationTag traffic_annotation,
149 ProxyConfigWithAnnotation* config) {
150 WINHTTP_CURRENT_USER_IE_PROXY_CONFIG ie_config = {0};
151 if (!WinHttpGetIEProxyConfigForCurrentUser(&ie_config)) {
152 LOG(ERROR) << "WinHttpGetIEProxyConfigForCurrentUser failed: " <<
153 GetLastError();
154 *config = ProxyConfigWithAnnotation::CreateDirect();
155 return;
156 }
157 ProxyConfig proxy_config;
158 SetFromIEConfig(&proxy_config, ie_config);
159 FreeIEConfig(&ie_config);
160 proxy_config.set_from_system(true);
161 *config = ProxyConfigWithAnnotation(proxy_config, traffic_annotation);
162 }
163
164 // static
SetFromIEConfig(ProxyConfig * config,const WINHTTP_CURRENT_USER_IE_PROXY_CONFIG & ie_config)165 void ProxyConfigServiceWin::SetFromIEConfig(
166 ProxyConfig* config,
167 const WINHTTP_CURRENT_USER_IE_PROXY_CONFIG& ie_config) {
168 if (ie_config.fAutoDetect)
169 config->set_auto_detect(true);
170 if (ie_config.lpszProxy) {
171 // lpszProxy may be a single proxy, or a proxy per scheme. The format
172 // is compatible with ProxyConfig::ProxyRules's string format.
173 config->proxy_rules().ParseFromString(
174 base::WideToUTF8(ie_config.lpszProxy));
175 }
176 if (ie_config.lpszProxyBypass) {
177 std::string proxy_bypass = base::WideToUTF8(ie_config.lpszProxyBypass);
178
179 base::StringTokenizer proxy_server_bypass_list(proxy_bypass, ";, \t\n\r");
180 while (proxy_server_bypass_list.GetNext()) {
181 std::string bypass_url_domain = proxy_server_bypass_list.token();
182 config->proxy_rules().bypass_rules.AddRuleFromString(bypass_url_domain);
183 }
184 }
185 if (ie_config.lpszAutoConfigUrl)
186 config->set_pac_url(GURL(base::as_u16cstr(ie_config.lpszAutoConfigUrl)));
187 }
188
189 } // namespace net
190