blob: 7d512fb6c3c095c4a11b30be5f8b8947829cc11f [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 <memory>
#include <set>
#include <string>
#include <vector>
#include "base/gtest_prod_util.h"
#include "base/macros.h"
#include "base/memory/ref_counted.h"
#include "base/optional.h"
#include "base/synchronization/waitable_event.h"
#include "base/threading/thread_checker.h"
#include "net/base/completion_once_callback.h"
#include "net/base/load_states.h"
#include "net/base/net_export.h"
#include "net/base/network_change_notifier.h"
#include "net/base/proxy_server.h"
#include "net/log/net_log_with_source.h"
#include "net/proxy_resolution/proxy_config_service.h"
#include "net/proxy_resolution/proxy_config_with_annotation.h"
#include "net/proxy_resolution/proxy_info.h"
#include "net/proxy_resolution/proxy_resolver.h"
#include "starboard/types.h"
#include "url/gurl.h"
class GURL;
namespace base {
class SequencedTaskRunner;
class TimeDelta;
} // namespace base
namespace net {
class DhcpPacFileFetcher;
class NetLog;
class ProxyDelegate;
class ProxyResolverFactory;
class PacFileData;
class PacFileFetcher;
// 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 ProxyResolutionService
: public NetworkChangeNotifier::IPAddressObserver,
public NetworkChangeNotifier::DNSObserver,
public ProxyConfigService::Observer {
// Enumerates the policy to use when sanitizing URLs for proxy resolution
// (before passing them off to PAC scripts).
enum class SanitizeUrlPolicy {
// Do a basic level of sanitization for URLs:
// - strip embedded identities (ex: "username:password@")
// - strip the fragment (ex: "#blah")
// This is considered "unsafe" because it does not do any additional
// stripping for https:// URLs.
// SAFE does the same sanitization as UNSAFE, but additionally strips
// everything but the (scheme,host,port) from cryptographic URL schemes
// (https:// and wss://).
// In other words, it strips the path and query portion of https:// URLs.
// 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;
// |net_log| is a possibly NULL destination to send log events to. It must
// remain alive for the lifetime of this ProxyResolutionService.
ProxyResolutionService(std::unique_ptr<ProxyConfigService> config_service,
std::unique_ptr<ProxyResolverFactory> resolver_factory,
NetLog* net_log);
~ProxyResolutionService() override;
// Used to track proxy resolution requests that complete asynchronously.
class Request {
virtual ~Request() = default;
virtual LoadState GetLoadState() const = 0;
Request() = default;
// Determines the appropriate proxy for |url| for a |method| request and
// stores the result in |results|. If |method| is empty, the caller can expect
// method independent resolution.
// 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 |request| is cancelled,
// which occurs when the unique pointer to it is deleted (by leaving scope or
// otherwise). |request| must not be NULL.
// 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,
const std::string& method,
ProxyInfo* results,
CompletionOnceCallback callback,
std::unique_ptr<Request>* request,
const NetLogWithSource& net_log);
// Explicitly trigger proxy fallback for the given |results| by updating our
// list of bad proxies to include the first entry of |results|, and,
// additional bad proxies (can be none). Will retry after |retry_delay| if
// positive, and will use the default proxy retry duration otherwise. Proxies
// marked as bad will not be retried until |retry_delay| has passed. Returns
// true if there will be at least one proxy remaining in the list after
// fallback and false otherwise. This method should be used to add proxies to
// the bad proxy list only for reasons other than a network error.
bool MarkProxiesAsBadUntil(
const ProxyInfo& results,
base::TimeDelta retry_delay,
const std::vector<ProxyServer>& additional_bad_proxies,
const NetLogWithSource& 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);
// Sets the PacFileFetcher and DhcpPacFileFetcher dependencies. This
// is needed if the ProxyResolver is of type ProxyResolverWithoutFetch.
void SetPacFileFetchers(
std::unique_ptr<PacFileFetcher> pac_file_fetcher,
std::unique_ptr<DhcpPacFileFetcher> dhcp_pac_file_fetcher);
PacFileFetcher* GetPacFileFetcher() const;
// Associates a delegate that with this ProxyResolutionService. |delegate|
// must outlive |this|.
// TODO(eroman): Specify this as a dependency at construction time rather
// than making it a mutable property.
void SetProxyDelegate(ProxyDelegate* delegate);
// In builds with DCHECKs enabled, asserts that there isn't already a
// delegate associated with |this|.
void AssertNoProxyDelegate() const;
// Cancels all network requests, and prevents the service from creating new
// ones. Must be called before the URLRequestContext the
// ProxyResolutionService was created with is torn down, if it's torn down
// before th ProxyResolutionService itself.
void OnShutdown();
// Tells this ProxyResolutionService 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.
void ResetConfigService(
std::unique_ptr<ProxyConfigService> new_proxy_config_service);
// Returns the last configuration fetched from ProxyConfigService.
const base::Optional<ProxyConfigWithAnnotation>& fetched_config() const {
return fetched_config_;
// Returns the current configuration being used by ProxyConfigService.
const base::Optional<ProxyConfigWithAnnotation>& config() const {
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 CreateProxyResolutionServiceUsingV8ProxyResolver, except it uses
// system libraries for evaluating the PAC script if available, otherwise
// skips proxy autoconfig.
static std::unique_ptr<ProxyResolutionService> CreateUsingSystemProxyResolver(
std::unique_ptr<ProxyConfigService> proxy_config_service,
NetLog* net_log);
// Creates a ProxyResolutionService without support for proxy autoconfig.
static std::unique_ptr<ProxyResolutionService> CreateWithoutProxyResolver(
std::unique_ptr<ProxyConfigService> proxy_config_service,
NetLog* net_log);
// Convenience methods that creates a proxy service using the
// specified fixed settings.
static std::unique_ptr<ProxyResolutionService> CreateFixed(
const ProxyConfigWithAnnotation& pc);
static std::unique_ptr<ProxyResolutionService> CreateFixed(
const std::string& proxy,
const NetworkTrafficAnnotationTag& traffic_annotation);
// Creates a proxy service that uses a DIRECT connection for all requests.
static std::unique_ptr<ProxyResolutionService> CreateDirect();
// This method is used by tests to create a ProxyResolutionService 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 std::unique_ptr<ProxyResolutionService> CreateFixedFromPacResult(
const std::string& pac_string,
const NetworkTrafficAnnotationTag& traffic_annotation);
// Creates a config service appropriate for this platform that fetches the
// system proxy settings. |main_task_runner| is the thread where the consumer
// of the ProxyConfigService will live.
// TODO(mmenke): Should this be a member of ProxyConfigService?
// The ProxyResolutionService may not even be in the same process as the
// system ProxyConfigService.
static std::unique_ptr<ProxyConfigService> CreateSystemProxyConfigService(
const scoped_refptr<base::SequencedTaskRunner>& main_task_runner);
// 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 ProxyResolutionService.
static std::unique_ptr<PacPollPolicy> CreateDefaultPacPollPolicy();
void set_quick_check_enabled(bool value) {
quick_check_enabled_ = value;
bool quick_check_enabled_for_testing() const { return quick_check_enabled_; }
void set_sanitize_url_policy(SanitizeUrlPolicy policy) {
sanitize_url_policy_ = policy;
SanitizeUrlPolicy sanitize_url_policy_for_testing() const {
return sanitize_url_policy_;
class InitProxyResolver;
class PacFileDeciderPoller;
class RequestImpl;
typedef std::set<RequestImpl*> 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 SetReady().
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(RequestImpl* req);
// Removes |req| from the list of pending requests.
void RemovePendingRequest(RequestImpl* 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(const GURL& url,
const std::string& method,
ProxyInfo* result,
int result_code,
const NetLogWithSource& net_log);
// Start initialization using |fetched_config_|.
void InitializeUsingLastFetchedConfig();
// Start the initialization skipping past the "decision" phase.
void InitializeUsingDecidedConfig(
int decider_result,
PacFileData* script_data,
const ProxyConfigWithAnnotation& effective_config);
// NetworkChangeNotifier::IPAddressObserver
// When this is called, we re-fetch PAC scripts and re-run WPAD.
void OnIPAddressChanged() override;
// NetworkChangeNotifier::DNSObserver
// We respond as above.
void OnDNSChanged() override;
// ProxyConfigService::Observer
void OnProxyConfigChanged(
const ProxyConfigWithAnnotation& config,
ProxyConfigService::ConfigAvailability availability) override;
std::unique_ptr<ProxyConfigService> config_service_;
std::unique_ptr<ProxyResolverFactory> resolver_factory_;
std::unique_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).
// These are "optional" as their value remains unset while being calculated.
base::Optional<ProxyConfigWithAnnotation> fetched_config_;
base::Optional<ProxyConfigWithAnnotation> config_;
// 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.
std::unique_ptr<PacFileFetcher> pac_file_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.
std::unique_ptr<DhcpPacFileFetcher> dhcp_pac_file_fetcher_;
// Helper to download the PAC script (wpad + custom) and apply fallback rules.
// Note that the declaration is important here: |pac_file_fetcher_| and
// |proxy_resolver_| must outlive |init_proxy_resolver_|.
std::unique_ptr<InitProxyResolver> init_proxy_resolver_;
// Helper to poll the PAC script for changes.
std::unique_ptr<PacFileDeciderPoller> 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_;
// Whether child PacFileDeciders should use QuickCheck
bool quick_check_enabled_;
// The method to use for sanitizing URLs seen by the proxy resolver.
SanitizeUrlPolicy sanitize_url_policy_;
ProxyDelegate* proxy_delegate_ = nullptr;
// Flag used by |SetReady()| to check if |this| has been deleted by a
// synchronous callback.
base::WeakPtrFactory<ProxyResolutionService> weak_ptr_factory_;
} // namespace net