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 "net/proxy/proxy_resolver_winhttp.h"
6
7#include <windows.h>
8#include <winhttp.h>
9
10#include "base/metrics/histogram.h"
11#include "base/strings/string_util.h"
12#include "base/strings/utf_string_conversions.h"
13#include "net/base/net_errors.h"
14#include "net/proxy/proxy_info.h"
15#include "url/gurl.h"
16
17#pragma comment(lib, "winhttp.lib")
18
19using base::TimeDelta;
20using base::TimeTicks;
21
22namespace net {
23
24static void FreeInfo(WINHTTP_PROXY_INFO* info) {
25  if (info->lpszProxy)
26    GlobalFree(info->lpszProxy);
27  if (info->lpszProxyBypass)
28    GlobalFree(info->lpszProxyBypass);
29}
30
31ProxyResolverWinHttp::ProxyResolverWinHttp()
32    : ProxyResolver(false /*expects_pac_bytes*/), session_handle_(NULL) {
33}
34
35ProxyResolverWinHttp::~ProxyResolverWinHttp() {
36  CloseWinHttpSession();
37}
38
39int ProxyResolverWinHttp::GetProxyForURL(const GURL& query_url,
40                                         ProxyInfo* results,
41                                         const CompletionCallback& /*callback*/,
42                                         RequestHandle* /*request*/,
43                                         const BoundNetLog& /*net_log*/) {
44  // If we don't have a WinHTTP session, then create a new one.
45  if (!session_handle_ && !OpenWinHttpSession())
46    return ERR_FAILED;
47
48  // If we have been given an empty PAC url, then use auto-detection.
49  //
50  // NOTE: We just use DNS-based auto-detection here like Firefox.  We do this
51  // to avoid WinHTTP's auto-detection code, which while more featureful (it
52  // supports DHCP based auto-detection) also appears to have issues.
53  //
54  WINHTTP_AUTOPROXY_OPTIONS options = {0};
55  options.fAutoLogonIfChallenged = FALSE;
56  options.dwFlags = WINHTTP_AUTOPROXY_CONFIG_URL;
57  std::wstring pac_url_wide = base::ASCIIToWide(pac_url_.spec());
58  options.lpszAutoConfigUrl = pac_url_wide.c_str();
59
60  WINHTTP_PROXY_INFO info = {0};
61  DCHECK(session_handle_);
62
63  // Per http://msdn.microsoft.com/en-us/library/aa383153(VS.85).aspx, it is
64  // necessary to first try resolving with fAutoLogonIfChallenged set to false.
65  // Otherwise, we fail over to trying it with a value of true.  This way we
66  // get good performance in the case where WinHTTP uses an out-of-process
67  // resolver.  This is important for Vista and Win2k3.
68  BOOL ok = WinHttpGetProxyForUrl(session_handle_,
69                                  base::ASCIIToWide(query_url.spec()).c_str(),
70                                  &options, &info);
71  if (!ok) {
72    if (ERROR_WINHTTP_LOGIN_FAILURE == GetLastError()) {
73      options.fAutoLogonIfChallenged = TRUE;
74      ok = WinHttpGetProxyForUrl(
75          session_handle_, base::ASCIIToWide(query_url.spec()).c_str(),
76          &options, &info);
77    }
78    if (!ok) {
79      DWORD error = GetLastError();
80      // If we got here because of RPC timeout during out of process PAC
81      // resolution, no further requests on this session are going to work.
82      if (ERROR_WINHTTP_TIMEOUT == error ||
83          ERROR_WINHTTP_AUTO_PROXY_SERVICE_ERROR == error) {
84        CloseWinHttpSession();
85      }
86      return ERR_FAILED;  // TODO(darin): Bug 1189288: translate error code.
87    }
88  }
89
90  int rv = OK;
91
92  switch (info.dwAccessType) {
93    case WINHTTP_ACCESS_TYPE_NO_PROXY:
94      results->UseDirect();
95      break;
96    case WINHTTP_ACCESS_TYPE_NAMED_PROXY:
97      // According to MSDN:
98      //
99      // The proxy server list contains one or more of the following strings
100      // separated by semicolons or whitespace.
101      //
102      // ([<scheme>=][<scheme>"://"]<server>[":"<port>])
103      //
104      // Based on this description, ProxyInfo::UseNamedProxy() isn't
105      // going to handle all the variations (in particular <scheme>=).
106      //
107      // However in practice, it seems that WinHTTP is simply returning
108      // things like "foopy1:80;foopy2:80". It strips out the non-HTTP
109      // proxy types, and stops the list when PAC encounters a "DIRECT".
110      // So UseNamedProxy() should work OK.
111      results->UseNamedProxy(base::UTF16ToASCII(info.lpszProxy));
112      break;
113    default:
114      NOTREACHED();
115      rv = ERR_FAILED;
116  }
117
118  FreeInfo(&info);
119  return rv;
120}
121
122void ProxyResolverWinHttp::CancelRequest(RequestHandle request) {
123  // This is a synchronous ProxyResolver; no possibility for async requests.
124  NOTREACHED();
125}
126
127LoadState ProxyResolverWinHttp::GetLoadState(RequestHandle request) const {
128  NOTREACHED();
129  return LOAD_STATE_IDLE;
130}
131
132void ProxyResolverWinHttp::CancelSetPacScript() {
133  NOTREACHED();
134}
135
136int ProxyResolverWinHttp::SetPacScript(
137    const scoped_refptr<ProxyResolverScriptData>& script_data,
138    const CompletionCallback& /*callback*/) {
139  if (script_data->type() == ProxyResolverScriptData::TYPE_AUTO_DETECT) {
140    pac_url_ = GURL("http://wpad/wpad.dat");
141  } else {
142    pac_url_ = script_data->url();
143  }
144  return OK;
145}
146
147bool ProxyResolverWinHttp::OpenWinHttpSession() {
148  DCHECK(!session_handle_);
149  session_handle_ = WinHttpOpen(NULL,
150                                WINHTTP_ACCESS_TYPE_NO_PROXY,
151                                WINHTTP_NO_PROXY_NAME,
152                                WINHTTP_NO_PROXY_BYPASS,
153                                0);
154  if (!session_handle_)
155    return false;
156
157  // Since this session handle will never be used for WinHTTP connections,
158  // these timeouts don't really mean much individually.  However, WinHTTP's
159  // out of process PAC resolution will use a combined (sum of all timeouts)
160  // value to wait for an RPC reply.
161  BOOL rv = WinHttpSetTimeouts(session_handle_, 10000, 10000, 5000, 5000);
162  DCHECK(rv);
163
164  return true;
165}
166
167void ProxyResolverWinHttp::CloseWinHttpSession() {
168  if (session_handle_) {
169    WinHttpCloseHandle(session_handle_);
170    session_handle_ = NULL;
171  }
172}
173
174}  // namespace net
175