blob: 500d2a1141e0b62ecf05eebe30a3856b06cfce2b [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.
#include <string>
#include <vector>
#include "base/gtest_prod_util.h"
#include "base/memory/ref_counted.h"
#include "base/memory/scoped_ptr.h"
#include "base/synchronization/waitable_event.h"
#include "base/threading/non_thread_safe.h"
#include "net/base/completion_callback.h"
#include "net/base/load_states.h"
#include "net/base/net_export.h"
#include "net/base/net_log.h"
#include "net/base/network_change_notifier.h"
#include "net/proxy/proxy_config_service.h"
#include "net/proxy/proxy_info.h"
#include "net/proxy/proxy_server.h"
class GURL;
class MessageLoop;
namespace base {
class SingleThreadTaskRunner;
} // namespace base
namespace net {
class DhcpProxyScriptFetcher;
class HostResolver;
class NetworkDelegate;
class ProxyResolver;
class ProxyResolverScriptData;
class ProxyScriptDecider;
class ProxyScriptFetcher;
// This class can be used to resolve the proxy server to use when loading a
// HTTP(S) URL. It uses the given ProxyResolver to handle the actual proxy
// resolution. See ProxyResolverV8 for example.
class NET_EXPORT ProxyService : public NetworkChangeNotifier::IPAddressObserver,
public ProxyConfigService::Observer,
NON_EXPORTED_BASE(public base::NonThreadSafe) {
static const size_t kDefaultNumPacThreads = 4;
// This interface defines the set of policies for when to poll the PAC
// script for changes.
// The polling policy decides what the next poll delay should be in
// milliseconds. It also decides how to wait for this delay -- either
// by starting a timer to do the poll at exactly |next_delay_ms|
// (MODE_USE_TIMER) or by waiting for the first network request issued after
// |next_delay_ms| (MODE_START_AFTER_ACTIVITY).
// The timer method is more precise and guarantees that polling happens when
// it was requested. However it has the disadvantage of causing spurious CPU
// and network activity. It is a reasonable choice to use for short poll
// intervals which only happen a couple times.
// However for repeated timers this will prevent the browser from going
// idle. MODE_START_AFTER_ACTIVITY solves this problem by only polling in
// direct response to network activity. The drawback to
// MODE_START_AFTER_ACTIVITY is since the poll is initiated only after the
// request is received, the first couple requests initiated after a long
// period of inactivity will likely see a stale version of the PAC script
// until the background polling gets a chance to update things.
class NET_EXPORT_PRIVATE PacPollPolicy {
enum Mode {
virtual ~PacPollPolicy() {}
// Decides the next poll delay. |current_delay| is the delay used
// by the preceding poll, or a negative TimeDelta value if determining
// the delay for the initial poll. |initial_error| is the network error
// code that the last PAC fetch (or WPAD initialization) failed with,
// or OK if it completed successfully. Implementations must set
// |next_delay| to a non-negative value.
virtual Mode GetNextDelay(int initial_error,
base::TimeDelta current_delay,
base::TimeDelta* next_delay) const = 0;
// The instance takes ownership of |config_service| and |resolver|.
// |net_log| is a possibly NULL destination to send log events to. It must
// remain alive for the lifetime of this ProxyService.
ProxyService(ProxyConfigService* config_service,
ProxyResolver* resolver,
NetLog* net_log);
virtual ~ProxyService();
// Used internally to handle PAC queries.
// TODO(eroman): consider naming this simply "Request".
class PacRequest;
// Returns ERR_IO_PENDING if the proxy information could not be provided
// synchronously, to indicate that the result will be available when the
// callback is run. The callback is run on the thread that calls
// ResolveProxy.
// The caller is responsible for ensuring that |results| and |callback|
// remain valid until the callback is run or until |pac_request| is cancelled
// via CancelPacRequest. |pac_request| is only valid while the completion
// callback is still pending. NULL can be passed for |pac_request| if
// the caller will not need to cancel the request.
// We use the three possible proxy access types in the following order,
// doing fallback if one doesn't work. See "pac_script_decider.h"
// for the specifics.
// 1. WPAD auto-detection
// 2. PAC URL
// 3. named proxy
// Profiling information for the request is saved to |net_log| if non-NULL.
int ResolveProxy(const GURL& url,
ProxyInfo* results,
const net::CompletionCallback& callback,
PacRequest** pac_request,
const BoundNetLog& net_log);
// This method is called after a failure to connect or resolve a host name.
// It gives the proxy service an opportunity to reconsider the proxy to use.
// The |results| parameter contains the results returned by an earlier call
// to ResolveProxy. The semantics of this call are otherwise similar to
// ResolveProxy.
// NULL can be passed for |pac_request| if the caller will not need to
// cancel the request.
// Returns ERR_FAILED if there is not another proxy config to try.
// Profiling information for the request is saved to |net_log| if non-NULL.
int ReconsiderProxyAfterError(const GURL& url,
ProxyInfo* results,
const CompletionCallback& callback,
PacRequest** pac_request,
const BoundNetLog& net_log);
// Explicitly trigger proxy fallback for the given |results| by updating our
// list of bad proxies to include the first entry of |results|. Returns true
// if there will be at least one proxy remaining in the list after fallback
// and false otherwise.
bool MarkProxyAsBad(const ProxyInfo& results, const BoundNetLog& net_log);
// Called to report that the last proxy connection succeeded. If |proxy_info|
// has a non empty proxy_retry_info map, the proxies that have been tried (and
// failed) for this request will be marked as bad.
void ReportSuccess(const ProxyInfo& proxy_info);
// Call this method with a non-null |pac_request| to cancel the PAC request.
void CancelPacRequest(PacRequest* pac_request);
// Returns the LoadState for this |pac_request| which must be non-NULL.
LoadState GetLoadState(const PacRequest* pac_request) const;
// Sets the ProxyScriptFetcher and DhcpProxyScriptFetcher dependencies. This
// is needed if the ProxyResolver is of type ProxyResolverWithoutFetch.
// ProxyService takes ownership of both objects.
void SetProxyScriptFetchers(
ProxyScriptFetcher* proxy_script_fetcher,
DhcpProxyScriptFetcher* dhcp_proxy_script_fetcher);
ProxyScriptFetcher* GetProxyScriptFetcher() const;
// Tells this ProxyService to start using a new ProxyConfigService to
// retrieve its ProxyConfig from. The new ProxyConfigService will immediately
// be queried for new config info which will be used for all subsequent
// ResolveProxy calls. ProxyService takes ownership of
// |new_proxy_config_service|.
void ResetConfigService(ProxyConfigService* new_proxy_config_service);
// Tells the resolver to purge any memory it does not need.
void PurgeMemory();
// Returns the last configuration fetched from ProxyConfigService.
const ProxyConfig& fetched_config() {
return fetched_config_;
// Returns the current configuration being used by ProxyConfigService.
const ProxyConfig& config() {
return config_;
// Returns the map of proxies which have been marked as "bad".
const ProxyRetryInfoMap& proxy_retry_info() const {
return proxy_retry_info_;
// Clears the list of bad proxy servers that has been cached.
void ClearBadProxiesCache() {
// Forces refetching the proxy configuration, and applying it.
// This re-does everything from fetching the system configuration,
// to downloading and testing the PAC files.
void ForceReloadProxyConfig();
// Same as CreateProxyServiceUsingV8ProxyResolver, except it uses system
// libraries for evaluating the PAC script if available, otherwise skips
// proxy autoconfig.
static ProxyService* CreateUsingSystemProxyResolver(
ProxyConfigService* proxy_config_service,
size_t num_pac_threads,
NetLog* net_log);
// Creates a ProxyService without support for proxy autoconfig.
static ProxyService* CreateWithoutProxyResolver(
ProxyConfigService* proxy_config_service,
NetLog* net_log);
// Convenience methods that creates a proxy service using the
// specified fixed settings.
static ProxyService* CreateFixed(const ProxyConfig& pc);
static ProxyService* CreateFixed(const std::string& proxy);
// Creates a proxy service that uses a DIRECT connection for all requests.
static ProxyService* CreateDirect();
// |net_log|'s lifetime must exceed ProxyService.
static ProxyService* CreateDirectWithNetLog(NetLog* net_log);
// This method is used by tests to create a ProxyService that returns a
// hardcoded proxy fallback list (|pac_string|) for every URL.
// |pac_string| is a list of proxy servers, in the format that a PAC script
// would return it. For example, "PROXY foobar:99; SOCKS fml:2; DIRECT"
static ProxyService* CreateFixedFromPacResult(const std::string& pac_string);
// Creates a config service appropriate for this platform that fetches the
// system proxy settings.
static ProxyConfigService* CreateSystemProxyConfigService(
base::SingleThreadTaskRunner* io_thread_task_runner,
MessageLoop* file_loop);
// This method should only be used by unit tests.
void set_stall_proxy_auto_config_delay(base::TimeDelta delay) {
stall_proxy_auto_config_delay_ = delay;
// This method should only be used by unit tests. Returns the previously
// active policy.
static const PacPollPolicy* set_pac_script_poll_policy(
const PacPollPolicy* policy);
// This method should only be used by unit tests. Creates an instance
// of the default internal PacPollPolicy used by ProxyService.
static scoped_ptr<PacPollPolicy> CreateDefaultPacPollPolicy();
FRIEND_TEST_ALL_PREFIXES(ProxyServiceTest, UpdateConfigAfterFailedAutodetect);
FRIEND_TEST_ALL_PREFIXES(ProxyServiceTest, UpdateConfigFromPACToDirect);
friend class PacRequest;
class InitProxyResolver;
class ProxyScriptDeciderPoller;
// TODO(eroman): change this to a std::set. Note that this requires updating
// some tests in such as:
// ProxyServiceTest.InitialPACScriptDownload
// which expects requests to finish in the order they were added.
typedef std::vector<scoped_refptr<PacRequest> > PendingRequests;
enum State {
// Resets all the variables associated with the current proxy configuration,
// and rewinds the current state to |STATE_NONE|. Returns the previous value
// of |current_state_|. If |reset_fetched_config| is true then
// |fetched_config_| will also be reset, otherwise it will be left as-is.
// Resetting it means that we will have to re-fetch the configuration from
// the ProxyConfigService later.
State ResetProxyConfig(bool reset_fetched_config);
// Retrieves the current proxy configuration from the ProxyConfigService, and
// starts initializing for it.
void ApplyProxyConfigIfAvailable();
// Callback for when the proxy resolver has been initialized with a
// PAC script.
void OnInitProxyResolverComplete(int result);
// Returns ERR_IO_PENDING if the request cannot be completed synchronously.
// Otherwise it fills |result| with the proxy information for |url|.
// Completing synchronously means we don't need to query ProxyResolver.
int TryToCompleteSynchronously(const GURL& url, ProxyInfo* result);
// Cancels all of the requests sent to the ProxyResolver. These will be
// restarted when calling ResumeAllPendingRequests().
void SuspendAllPendingRequests();
// Advances the current state to |STATE_READY|, and resumes any pending
// requests which had been stalled waiting for initialization to complete.
void SetReady();
// Returns true if |pending_requests_| contains |req|.
bool ContainsPendingRequest(PacRequest* req);
// Removes |req| from the list of pending requests.
void RemovePendingRequest(PacRequest* req);
// Called when proxy resolution has completed (either synchronously or
// asynchronously). Handles logging the result, and cleaning out
// bad entries from the results list.
int DidFinishResolvingProxy(ProxyInfo* result,
int result_code,
const BoundNetLog& net_log);
// Start initialization using |fetched_config_|.
void InitializeUsingLastFetchedConfig();
// Start the initialization skipping past the "decision" phase.
void InitializeUsingDecidedConfig(
int decider_result,
ProxyResolverScriptData* script_data,
const ProxyConfig& effective_config);
// NetworkChangeNotifier::IPAddressObserver
// When this is called, we re-fetch PAC scripts and re-run WPAD.
virtual void OnIPAddressChanged() OVERRIDE;
// ProxyConfigService::Observer
virtual void OnProxyConfigChanged(
const ProxyConfig& config,
ProxyConfigService::ConfigAvailability availability) OVERRIDE;
scoped_ptr<ProxyConfigService> config_service_;
scoped_ptr<ProxyResolver> resolver_;
// We store the proxy configuration that was last fetched from the
// ProxyConfigService, as well as the resulting "effective" configuration.
// The effective configuration is what we condense the original fetched
// settings to after testing the various automatic settings (auto-detect
// and custom PAC url).
ProxyConfig fetched_config_;
ProxyConfig config_;
// Increasing ID to give to the next ProxyConfig that we set.
int next_config_id_;
// The time when the proxy configuration was last read from the system.
base::TimeTicks config_last_update_time_;
// Map of the known bad proxies and the information about the retry time.
ProxyRetryInfoMap proxy_retry_info_;
// Set of pending/inprogress requests.
PendingRequests pending_requests_;
// The fetcher to use when downloading PAC scripts for the ProxyResolver.
// This dependency can be NULL if our ProxyResolver has no need for
// external PAC script fetching.
scoped_ptr<ProxyScriptFetcher> proxy_script_fetcher_;
// The fetcher to use when attempting to download the most appropriate PAC
// script configured in DHCP, if any. Can be NULL if the ProxyResolver has
// no need for DHCP PAC script fetching.
scoped_ptr<DhcpProxyScriptFetcher> dhcp_proxy_script_fetcher_;
// Helper to download the PAC script (wpad + custom) and apply fallback rules.
// Note that the declaration is important here: |proxy_script_fetcher_| and
// |proxy_resolver_| must outlive |init_proxy_resolver_|.
scoped_ptr<InitProxyResolver> init_proxy_resolver_;
// Helper to poll the PAC script for changes.
scoped_ptr<ProxyScriptDeciderPoller> script_poller_;
State current_state_;
// Either OK or an ERR_* value indicating that a permanent error (e.g.
// failed to fetch the PAC script) prevents proxy resolution.
int permanent_error_;
// This is the log where any events generated by |init_proxy_resolver_| are
// sent to.
NetLog* net_log_;
// The earliest time at which we should run any proxy auto-config. (Used to
// stall re-configuration following an IP address change).
base::TimeTicks stall_proxy_autoconfig_until_;
// The amount of time to stall requests following IP address changes.
base::TimeDelta stall_proxy_auto_config_delay_;
// Wrapper for invoking methods on a ProxyService synchronously.
class NET_EXPORT SyncProxyServiceHelper
: public base::RefCountedThreadSafe<SyncProxyServiceHelper> {
SyncProxyServiceHelper(MessageLoop* io_message_loop,
ProxyService* proxy_service);
int ResolveProxy(const GURL& url,
ProxyInfo* proxy_info,
const BoundNetLog& net_log);
int ReconsiderProxyAfterError(const GURL& url,
ProxyInfo* proxy_info,
const BoundNetLog& net_log);
friend class base::RefCountedThreadSafe<SyncProxyServiceHelper>;
virtual ~SyncProxyServiceHelper();
void StartAsyncResolve(const GURL& url, const BoundNetLog& net_log);
void StartAsyncReconsider(const GURL& url, const BoundNetLog& net_log);
void OnCompletion(int result);
MessageLoop* io_message_loop_;
ProxyService* proxy_service_;
base::WaitableEvent event_;
CompletionCallback callback_;
ProxyInfo proxy_info_;
int result_;
} // namespace net