// Copyright 2017 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 SERVICES_NETWORK_NETWORK_SERVICE_H_
#define SERVICES_NETWORK_NETWORK_SERVICE_H_

#include <map>
#include <memory>
#include <set>
#include <string>
#include <utility>
#include <vector>

#include "base/component_export.h"
#include "base/containers/flat_set.h"
#include "base/containers/span.h"
#include "base/containers/unique_ptr_adapters.h"
#include "base/macros.h"
#include "base/memory/scoped_refptr.h"
#include "base/optional.h"
#include "base/time/time.h"
#include "base/timer/timer.h"
#include "build/build_config.h"
#include "mojo/public/cpp/bindings/binding.h"
#include "net/http/http_auth_preferences.h"
#include "net/log/net_log.h"
#include "net/log/trace_net_log_observer.h"
#include "services/network/keepalive_statistics_recorder.h"
#include "services/network/network_change_manager.h"
#include "services/network/network_quality_estimator_manager.h"
#include "services/network/public/cpp/network_service_buildflags.h"
#include "services/network/public/mojom/host_resolver.mojom.h"
#include "services/network/public/mojom/net_log.mojom.h"
#include "services/network/public/mojom/network_change_manager.mojom.h"
#include "services/network/public/mojom/network_quality_estimator_manager.mojom.h"
#include "services/network/public/mojom/network_service.mojom.h"
#include "services/service_manager/public/cpp/binder_registry.h"
#include "services/service_manager/public/cpp/service.h"
#include "services/service_manager/public/cpp/service_binding.h"
#include "services/service_manager/public/mojom/service.mojom.h"

namespace net {
class FileNetLogObserver;
class HostResolverManager;
class HttpAuthHandlerFactory;
class LoggingNetworkChangeObserver;
class NetworkQualityEstimator;
class URLRequestContext;
}  // namespace net

#if BUILDFLAG(IS_CT_SUPPORTED)
namespace certificate_transparency {
class STHDistributor;
class STHReporter;
}  // namespace certificate_transparency
#endif  // BUILDFLAG(IS_CT_SUPPORTED)

namespace network {

class CRLSetDistributor;
class DnsConfigChangeManager;
class HttpAuthCacheCopier;
class NetworkContext;
class NetworkUsageAccumulator;
class URLRequestContextBuilderMojo;

class COMPONENT_EXPORT(NETWORK_SERVICE) NetworkService
    : public service_manager::Service,
      public mojom::NetworkService {
 public:
  // |net_log| is an optional shared NetLog, which will be used instead of the
  // service's own NetLog. It must outlive the NetworkService.
  //
  // TODO(https://crbug.com/767450): Once the NetworkService can always create
  // its own NetLog in production, remove the |net_log| argument.
  NetworkService(
      std::unique_ptr<service_manager::BinderRegistry> registry,
      mojom::NetworkServiceRequest request = nullptr,
      net::NetLog* net_log = nullptr,
      service_manager::mojom::ServiceRequest service_request = nullptr,
      bool delay_initialization_until_set_client = false);

  ~NetworkService() override;

  // Call to inform the NetworkService that OSCrypt::SetConfig() has already
  // been invoked, so OSCrypt::SetConfig() does not need to be called before
  // encrypted storage can be used.
  void set_os_crypt_is_configured();

  // Can be used to seed a NetworkContext with a consumer-configured
  // URLRequestContextBuilder, which |params| will then be applied to. The
  // results URLRequestContext will be written to |url_request_context|, which
  // is owned by the NetworkContext, and can be further modified before first
  // use. The returned NetworkContext must be destroyed before the
  // NetworkService.
  //
  // This method is intended to ease the transition to an out-of-process
  // NetworkService, and will be removed once that ships. It should only be
  // called if the network service is disabled.
  std::unique_ptr<mojom::NetworkContext> CreateNetworkContextWithBuilder(
      mojom::NetworkContextRequest request,
      mojom::NetworkContextParamsPtr params,
      std::unique_ptr<URLRequestContextBuilderMojo> builder,
      net::URLRequestContext** url_request_context);

  // Allows late binding if the mojo request wasn't specified in the
  // constructor.
  void Bind(mojom::NetworkServiceRequest request);

  // Allows the browser process to synchronously initialize the NetworkService.
  // TODO(jam): remove this once the old path is gone.
  void Initialize(mojom::NetworkServiceParamsPtr params);

  // Creates a NetworkService instance on the current thread, optionally using
  // the passed-in NetLog. Does not take ownership of |net_log|. Must be
  // destroyed before |net_log|.
  //
  // TODO(https://crbug.com/767450): Make it so NetworkService can always create
  // its own NetLog, instead of sharing one.
  static std::unique_ptr<NetworkService> Create(
      mojom::NetworkServiceRequest request,
      net::NetLog* net_log = nullptr,
      service_manager::mojom::ServiceRequest service_request = nullptr);

  // Creates a testing instance of NetworkService not bound to an actual
  // Service pipe. This instance must be driven by direct calls onto the
  // NetworkService object.
  static std::unique_ptr<NetworkService> CreateForTesting();

  // Creates a testing instance of NetworkService similar to above, but the
  // instance is bound to |request|. Test code may use an appropriate Connector
  // to bind interface requests within this service instance.
  static std::unique_ptr<NetworkService> CreateForTesting(
      service_manager::mojom::ServiceRequest service_request);

  // These are called by NetworkContexts as they are being created and
  // destroyed.
  // TODO(mmenke):  Remove once all NetworkContexts are owned by the
  // NetworkService.
  void RegisterNetworkContext(NetworkContext* network_context);
  void DeregisterNetworkContext(NetworkContext* network_context);

  // Invokes net::CreateNetLogEntriesForActiveObjects(observer) on all
  // URLRequestContext's known to |this|.
  void CreateNetLogEntriesForActiveObjects(
      net::NetLog::ThreadSafeObserver* observer);

  // mojom::NetworkService implementation:
  void SetClient(mojom::NetworkServiceClientPtr client,
                 mojom::NetworkServiceParamsPtr params) override;
  void StartNetLog(base::File file,
                   net::NetLogCaptureMode capture_mode,
                   base::Value constants) override;
  void SetSSLKeyLogFile(const base::FilePath& file) override;
  void CreateNetworkContext(mojom::NetworkContextRequest request,
                            mojom::NetworkContextParamsPtr params) override;
  void ConfigureStubHostResolver(
      bool stub_resolver_enabled,
      base::Optional<std::vector<mojom::DnsOverHttpsServerPtr>>
          dns_over_https_servers) override;
  void DisableQuic() override;
  void SetUpHttpAuth(
      mojom::HttpAuthStaticParamsPtr http_auth_static_params) override;
  void ConfigureHttpAuthPrefs(
      mojom::HttpAuthDynamicParamsPtr http_auth_dynamic_params) override;
  void SetRawHeadersAccess(uint32_t process_id,
                           const std::vector<url::Origin>& origins) override;
  void GetNetworkChangeManager(
      mojom::NetworkChangeManagerRequest request) override;
  void GetNetworkQualityEstimatorManager(
      mojom::NetworkQualityEstimatorManagerRequest request) override;
  void GetDnsConfigChangeManager(
      mojom::DnsConfigChangeManagerRequest request) override;
  void GetTotalNetworkUsages(
      mojom::NetworkService::GetTotalNetworkUsagesCallback callback) override;
  void GetNetworkList(
      uint32_t policy,
      mojom::NetworkService::GetNetworkListCallback callback) override;
#if BUILDFLAG(IS_CT_SUPPORTED)
  void UpdateSignedTreeHead(const net::ct::SignedTreeHead& sth) override;
#endif  // !BUILDFLAG(IS_CT_SUPPORTED)
  void UpdateCRLSet(base::span<const uint8_t> crl_set) override;
  void OnCertDBChanged() override;
#if defined(OS_LINUX) && !defined(OS_CHROMEOS)
  void SetCryptConfig(mojom::CryptConfigPtr crypt_config) override;
#endif
#if defined(OS_MACOSX) && !defined(OS_IOS)
  void SetEncryptionKey(const std::string& encryption_key) override;
#endif
  void AddCorbExceptionForPlugin(uint32_t process_id) override;
  void RemoveCorbExceptionForPlugin(uint32_t process_id) override;
  void OnMemoryPressure(base::MemoryPressureListener::MemoryPressureLevel
                            memory_pressure_level) override;
#if defined(OS_ANDROID)
  void OnApplicationStateChange(base::android::ApplicationState state) override;
#endif
  void SetEnvironment(
      std::vector<mojom::EnvironmentVariablePtr> environment) override;

  // Returns the shared HttpAuthHandlerFactory for the NetworkService, creating
  // one if needed.
  net::HttpAuthHandlerFactory* GetHttpAuthHandlerFactory();

  // Notification that a URLLoader is about to start.
  void OnBeforeURLRequest();

  bool quic_disabled() const { return quic_disabled_; }
  bool HasRawHeadersAccess(uint32_t process_id, const GURL& resource_url) const;

  mojom::NetworkServiceClient* client() { return client_.get(); }
  net::NetworkQualityEstimator* network_quality_estimator() {
    return network_quality_estimator_manager_->GetNetworkQualityEstimator();
  }
  net::NetLog* net_log() const;
  KeepaliveStatisticsRecorder* keepalive_statistics_recorder() {
    return &keepalive_statistics_recorder_;
  }
  net::HostResolverManager* host_resolver_manager() {
    return host_resolver_manager_.get();
  }
  net::HostResolver::Factory* host_resolver_factory() {
    return host_resolver_factory_.get();
  }
  NetworkUsageAccumulator* network_usage_accumulator() {
    return network_usage_accumulator_.get();
  }
  HttpAuthCacheCopier* http_auth_cache_copier() {
    return http_auth_cache_copier_.get();
  }

#if BUILDFLAG(IS_CT_SUPPORTED)
  certificate_transparency::STHReporter* sth_reporter();
#endif  // BUILDFLAG(IS_CT_SUPPORTED)

  CRLSetDistributor* crl_set_distributor() {
    return crl_set_distributor_.get();
  }

  bool os_crypt_config_set() const { return os_crypt_config_set_; }

  void set_host_resolver_factory_for_testing(
      std::unique_ptr<net::HostResolver::Factory> host_resolver_factory) {
    host_resolver_factory_ = std::move(host_resolver_factory);
  }

  static NetworkService* GetNetworkServiceForTesting();

  // Tells the network service to not create a NetworkChangeNotifier instance.
  // Must be called before the network service is started.
  static void DisableNetworkChangeNotifierForTesting();

 private:
  // service_manager::Service implementation.
  void OnBindInterface(const service_manager::BindSourceInfo& source_info,
                       const std::string& interface_name,
                       mojo::ScopedMessagePipeHandle interface_pipe) override;

  void DestroyNetworkContexts();

  // Called by a NetworkContext when its mojo pipe is closed. Deletes the
  // context.
  void OnNetworkContextConnectionClosed(NetworkContext* network_context);

  // Starts the timer to call NetworkServiceClient::OnLoadingStateUpdate(), if
  // timer isn't already running, |waiting_on_load_state_ack_| is false, and
  // there are live URLLoaders.
  // Only works when network service is enabled.
  void MaybeStartUpdateLoadInfoTimer();

  // Checks all pending requests and updates the load info if necessary.
  void UpdateLoadInfo();

  // Invoked once the browser has acknowledged receiving the previous LoadInfo.
  // Starts timer call UpdateLoadInfo() again, if needed.
  void AckUpdateLoadInfo();

  // Reports metrics on a periodically triggered repeating timer.
  void ReportMetrics();

  service_manager::ServiceBinding service_binding_{this};

  bool initialized_ = false;

  net::NetLog* net_log_ = nullptr;

  std::unique_ptr<net::FileNetLogObserver> file_net_log_observer_;
  net::TraceNetLogObserver trace_net_log_observer_;

  mojom::NetworkServiceClientPtr client_;

  KeepaliveStatisticsRecorder keepalive_statistics_recorder_;

  std::unique_ptr<NetworkChangeManager> network_change_manager_;

  // Observer that logs network changes to the NetLog. Must be below the NetLog
  // and the NetworkChangeNotifier (Once this class creates it), so it's
  // destroyed before them. Must be below the |network_change_manager_|, which
  // it references.
  std::unique_ptr<net::LoggingNetworkChangeObserver> network_change_observer_;

  std::unique_ptr<service_manager::BinderRegistry> registry_;

  mojo::Binding<mojom::NetworkService> binding_;

  std::unique_ptr<NetworkQualityEstimatorManager>
      network_quality_estimator_manager_;

  std::unique_ptr<DnsConfigChangeManager> dns_config_change_manager_;

  std::unique_ptr<net::HostResolverManager> host_resolver_manager_;
  std::unique_ptr<net::HostResolver::Factory> host_resolver_factory_;
  std::unique_ptr<NetworkUsageAccumulator> network_usage_accumulator_;

  // Must be above |http_auth_handler_factory_|, since it depends on this.
  net::HttpAuthPreferences http_auth_preferences_;
  std::unique_ptr<net::HttpAuthHandlerFactory> http_auth_handler_factory_;
  std::unique_ptr<HttpAuthCacheCopier> http_auth_cache_copier_;

  // NetworkContexts created by CreateNetworkContext(). They call into the
  // NetworkService when their connection is closed so that it can delete
  // them.  It will also delete them when the NetworkService itself is torn
  // down, as NetworkContexts share global state owned by the NetworkService, so
  // must be destroyed first.
  //
  // NetworkContexts created by CreateNetworkContextWithBuilder() are not owned
  // by the NetworkService, and must be destroyed by their owners before the
  // NetworkService itself is.
  std::set<std::unique_ptr<NetworkContext>, base::UniquePtrComparator>
      owned_network_contexts_;

  // List of all NetworkContexts that are associated with the NetworkService,
  // including ones it does not own.
  // TODO(mmenke): Once the NetworkService always owns NetworkContexts, merge
  // this with |owned_network_contexts_|.
  std::set<NetworkContext*> network_contexts_;

  // A per-process_id map of origins that are white-listed to allow
  // them to request raw headers for resources they request.
  std::map<uint32_t, base::flat_set<url::Origin>>
      raw_headers_access_origins_by_pid_;

  bool quic_disabled_ = false;

  bool os_crypt_config_set_ = false;

#if BUILDFLAG(IS_CT_SUPPORTED)
  std::unique_ptr<certificate_transparency::STHDistributor> sth_distributor_;
#endif  // BUILDFLAG(IS_CT_SUPPORTED)
  std::unique_ptr<CRLSetDistributor> crl_set_distributor_;

  // A timer that periodically calls UpdateLoadInfo while there are pending
  // loads and not waiting on an ACK from the client for the last sent
  // LoadInfo callback.
  base::OneShotTimer update_load_info_timer_;
  // True if a LoadInfoList has been sent to the client, but has yet to be
  // acknowledged.
  bool waiting_on_load_state_ack_ = false;

  // A timer that periodically calls ReportMetrics every hour.
  base::RepeatingTimer metrics_trigger_timer_;

  DISALLOW_COPY_AND_ASSIGN(NetworkService);
};

}  // namespace network

#endif  // SERVICES_NETWORK_NETWORK_SERVICE_H_