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.
5 #ifndef NET_PROXY_PROXY_SCRIPT_DECIDER_H_
6 #define NET_PROXY_PROXY_SCRIPT_DECIDER_H_
11 #include "base/memory/ref_counted.h"
12 #include "base/strings/string16.h"
13 #include "base/time/time.h"
14 #include "base/timer/timer.h"
15 #include "net/base/address_list.h"
16 #include "net/base/completion_callback.h"
17 #include "net/base/net_export.h"
18 #include "net/base/net_log.h"
19 #include "net/dns/host_resolver.h"
20 #include "net/dns/single_request_host_resolver.h"
21 #include "net/proxy/proxy_config.h"
22 #include "net/proxy/proxy_resolver.h"
27 class DhcpProxyScriptFetcher;
28 class NetLogParameter;
30 class ProxyScriptFetcher;
32 // ProxyScriptDecider is a helper class used by ProxyService to determine which
33 // PAC script to use given our proxy configuration.
35 // This involves trying to use PAC scripts in this order:
37 // (1) WPAD (DHCP) if auto-detect is on.
38 // (2) WPAD (DNS) if auto-detect is on.
39 // (3) Custom PAC script if a URL was given.
41 // If no PAC script was successfully selected, then it fails with either a
42 // network error, or PAC_SCRIPT_FAILED (indicating it did not pass our
45 // On successful completion, the fetched PAC script data can be accessed using
48 // Deleting ProxyScriptDecider while Init() is in progress, will
49 // cancel the request.
51 class NET_EXPORT_PRIVATE ProxyScriptDecider {
53 // |proxy_script_fetcher|, |dhcp_proxy_script_fetcher| and
54 // |net_log| must remain valid for the lifespan of ProxyScriptDecider.
55 ProxyScriptDecider(ProxyScriptFetcher* proxy_script_fetcher,
56 DhcpProxyScriptFetcher* dhcp_proxy_script_fetcher,
59 // Aborts any in-progress request.
60 ~ProxyScriptDecider();
62 // Evaluates the effective proxy settings for |config|, and downloads the
63 // associated PAC script.
64 // If |wait_delay| is positive, the initialization will pause for this
65 // amount of time before getting started.
66 // On successful completion, the "effective" proxy settings we ended up
67 // deciding on will be available vial the effective_settings() accessor.
68 // Note that this may differ from |config| since we will have stripped any
69 // manual settings, and decided whether to use auto-detect or the custom PAC
70 // URL. Finally, if auto-detect was used we may now have resolved that to a
71 // specific script URL.
72 int Start(const ProxyConfig& config,
73 const base::TimeDelta wait_delay,
75 const net::CompletionCallback& callback);
77 const ProxyConfig& effective_config() const;
79 // TODO(eroman): Return a const-pointer.
80 ProxyResolverScriptData* script_data() const;
83 // Represents the sources from which we can get PAC files; two types of
84 // auto-detect or a custom URL.
92 PacSource(Type type, const GURL& url)
93 : type(type), url(url) {}
95 // Returns a Value representing the PacSource. |effective_pac_url| must
96 // be non-NULL and point to the URL derived from information contained in
97 // |this|, if Type is not WPAD_DHCP.
98 base::Value* NetLogCallback(const GURL* effective_pac_url,
99 NetLog::LogLevel log_level) const;
102 GURL url; // Empty unless |type == PAC_SOURCE_CUSTOM|.
105 typedef std::vector<PacSource> PacSourceList;
112 STATE_QUICK_CHECK_COMPLETE,
113 STATE_FETCH_PAC_SCRIPT,
114 STATE_FETCH_PAC_SCRIPT_COMPLETE,
115 STATE_VERIFY_PAC_SCRIPT,
116 STATE_VERIFY_PAC_SCRIPT_COMPLETE,
119 // Returns ordered list of PAC urls to try for |config|.
120 PacSourceList BuildPacSourcesFallbackList(const ProxyConfig& config) const;
122 void OnIOCompletion(int result);
123 int DoLoop(int result);
124 void DoCallback(int result);
127 int DoWaitComplete(int result);
130 int DoQuickCheckComplete(int result);
132 int DoFetchPacScript();
133 int DoFetchPacScriptComplete(int result);
135 int DoVerifyPacScript();
136 int DoVerifyPacScriptComplete(int result);
138 // Tries restarting using the next fallback PAC URL:
139 // |pac_sources_[++current_pac_source_index]|.
140 // Returns OK and rewinds the state machine when there
141 // is something to try, otherwise returns |error|.
142 int TryToFallbackPacSource(int error);
144 // Gets the initial state (we skip fetching when the
145 // ProxyResolver doesn't |expect_pac_bytes()|.
146 State GetStartState() const;
148 void DetermineURL(const PacSource& pac_source, GURL* effective_pac_url);
150 // Returns the current PAC URL we are fetching/testing.
151 const PacSource& current_pac_source() const;
153 void OnWaitTimerFired();
157 ProxyResolver* resolver_;
158 ProxyScriptFetcher* proxy_script_fetcher_;
159 DhcpProxyScriptFetcher* dhcp_proxy_script_fetcher_;
161 net::CompletionCallback callback_;
163 size_t current_pac_source_index_;
165 // Filled when the PAC script fetch completes.
166 base::string16 pac_script_;
168 // Flag indicating whether the caller requested a mandatory pac script
169 // (i.e. fallback to direct connections are prohibited).
172 // Whether we have an existing custom PAC URL.
173 bool have_custom_pac_url_;
175 PacSourceList pac_sources_;
178 BoundNetLog net_log_;
180 bool fetch_pac_bytes_;
182 base::TimeDelta wait_delay_;
183 base::OneShotTimer<ProxyScriptDecider> wait_timer_;
186 ProxyConfig effective_config_;
187 scoped_refptr<ProxyResolverScriptData> script_data_;
189 AddressList wpad_addresses_;
190 base::OneShotTimer<ProxyScriptDecider> quick_check_timer_;
191 scoped_ptr<SingleRequestHostResolver> host_resolver_;
192 base::Time quick_check_start_time_;
194 DISALLOW_COPY_AND_ASSIGN(ProxyScriptDecider);
199 #endif // NET_PROXY_PROXY_SCRIPT_DECIDER_H_