blob: d5790806a1e84764706fc28c1df14bce37492586 [file] [log] [blame]
// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef NET_PROXY_PROXY_SCRIPT_DECIDER_H_
#define NET_PROXY_PROXY_SCRIPT_DECIDER_H_
#include <string>
#include <vector>
#include "base/memory/ref_counted.h"
#include "base/strings/string16.h"
#include "base/time/time.h"
#include "base/timer/timer.h"
#include "net/base/address_list.h"
#include "net/base/completion_callback.h"
#include "net/base/net_export.h"
#include "net/base/net_log.h"
#include "net/dns/host_resolver.h"
#include "net/dns/single_request_host_resolver.h"
#include "net/proxy/proxy_config.h"
#include "net/proxy/proxy_resolver.h"
#include "url/gurl.h"
namespace net {
class DhcpProxyScriptFetcher;
class NetLogParameter;
class ProxyResolver;
class ProxyScriptFetcher;
// ProxyScriptDecider is a helper class used by ProxyService to determine which
// PAC script to use given our proxy configuration.
//
// This involves trying to use PAC scripts in this order:
//
// (1) WPAD (DHCP) if auto-detect is on.
// (2) WPAD (DNS) if auto-detect is on.
// (3) Custom PAC script if a URL was given.
//
// If no PAC script was successfully selected, then it fails with either a
// network error, or PAC_SCRIPT_FAILED (indicating it did not pass our
// validation).
//
// On successful completion, the fetched PAC script data can be accessed using
// script_data().
//
// Deleting ProxyScriptDecider while Init() is in progress, will
// cancel the request.
//
class NET_EXPORT_PRIVATE ProxyScriptDecider {
public:
// |proxy_script_fetcher|, |dhcp_proxy_script_fetcher| and
// |net_log| must remain valid for the lifespan of ProxyScriptDecider.
ProxyScriptDecider(ProxyScriptFetcher* proxy_script_fetcher,
DhcpProxyScriptFetcher* dhcp_proxy_script_fetcher,
NetLog* net_log);
// Aborts any in-progress request.
~ProxyScriptDecider();
// Evaluates the effective proxy settings for |config|, and downloads the
// associated PAC script.
// If |wait_delay| is positive, the initialization will pause for this
// amount of time before getting started.
// On successful completion, the "effective" proxy settings we ended up
// deciding on will be available vial the effective_settings() accessor.
// Note that this may differ from |config| since we will have stripped any
// manual settings, and decided whether to use auto-detect or the custom PAC
// URL. Finally, if auto-detect was used we may now have resolved that to a
// specific script URL.
int Start(const ProxyConfig& config,
const base::TimeDelta wait_delay,
bool fetch_pac_bytes,
const net::CompletionCallback& callback);
const ProxyConfig& effective_config() const;
// TODO(eroman): Return a const-pointer.
ProxyResolverScriptData* script_data() const;
void set_quick_check_enabled(bool enabled) {
quick_check_enabled_ = enabled;
}
bool quick_check_enabled() const { return quick_check_enabled_; }
private:
// Represents the sources from which we can get PAC files; two types of
// auto-detect or a custom URL.
struct PacSource {
enum Type {
WPAD_DHCP,
WPAD_DNS,
CUSTOM
};
PacSource(Type type, const GURL& url)
: type(type), url(url) {}
// Returns a Value representing the PacSource. |effective_pac_url| must
// be non-NULL and point to the URL derived from information contained in
// |this|, if Type is not WPAD_DHCP.
base::Value* NetLogCallback(const GURL* effective_pac_url,
NetLog::LogLevel log_level) const;
Type type;
GURL url; // Empty unless |type == PAC_SOURCE_CUSTOM|.
};
typedef std::vector<PacSource> PacSourceList;
enum State {
STATE_NONE,
STATE_WAIT,
STATE_WAIT_COMPLETE,
STATE_QUICK_CHECK,
STATE_QUICK_CHECK_COMPLETE,
STATE_FETCH_PAC_SCRIPT,
STATE_FETCH_PAC_SCRIPT_COMPLETE,
STATE_VERIFY_PAC_SCRIPT,
STATE_VERIFY_PAC_SCRIPT_COMPLETE,
};
// Returns ordered list of PAC urls to try for |config|.
PacSourceList BuildPacSourcesFallbackList(const ProxyConfig& config) const;
void OnIOCompletion(int result);
int DoLoop(int result);
void DoCallback(int result);
int DoWait();
int DoWaitComplete(int result);
int DoQuickCheck();
int DoQuickCheckComplete(int result);
int DoFetchPacScript();
int DoFetchPacScriptComplete(int result);
int DoVerifyPacScript();
int DoVerifyPacScriptComplete(int result);
// Tries restarting using the next fallback PAC URL:
// |pac_sources_[++current_pac_source_index]|.
// Returns OK and rewinds the state machine when there
// is something to try, otherwise returns |error|.
int TryToFallbackPacSource(int error);
// Gets the initial state (we skip fetching when the
// ProxyResolver doesn't |expect_pac_bytes()|.
State GetStartState() const;
void DetermineURL(const PacSource& pac_source, GURL* effective_pac_url);
// Returns the current PAC URL we are fetching/testing.
const PacSource& current_pac_source() const;
void OnWaitTimerFired();
void DidComplete();
void Cancel();
ProxyResolver* resolver_;
ProxyScriptFetcher* proxy_script_fetcher_;
DhcpProxyScriptFetcher* dhcp_proxy_script_fetcher_;
net::CompletionCallback callback_;
size_t current_pac_source_index_;
// Filled when the PAC script fetch completes.
base::string16 pac_script_;
// Flag indicating whether the caller requested a mandatory pac script
// (i.e. fallback to direct connections are prohibited).
bool pac_mandatory_;
// Whether we have an existing custom PAC URL.
bool have_custom_pac_url_;
PacSourceList pac_sources_;
State next_state_;
BoundNetLog net_log_;
bool fetch_pac_bytes_;
base::TimeDelta wait_delay_;
base::OneShotTimer<ProxyScriptDecider> wait_timer_;
// Whether to do DNS quick check
bool quick_check_enabled_;
// Results.
ProxyConfig effective_config_;
scoped_refptr<ProxyResolverScriptData> script_data_;
AddressList wpad_addresses_;
base::OneShotTimer<ProxyScriptDecider> quick_check_timer_;
scoped_ptr<SingleRequestHostResolver> host_resolver_;
base::Time quick_check_start_time_;
DISALLOW_COPY_AND_ASSIGN(ProxyScriptDecider);
};
} // namespace net
#endif // NET_PROXY_PROXY_SCRIPT_DECIDER_H_