remoting/host/chromoting_host.h

   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.
   4
   5 #ifndef REMOTING_HOST_CHROMOTING_HOST_H_
   6 #define REMOTING_HOST_CHROMOTING_HOST_H_
   7
   8 #include <list>
   9 #include <string>
  10
  11 #include "base/memory/scoped_ptr.h"
  12 #include "base/memory/ref_counted.h"
  13 #include "base/memory/weak_ptr.h"
  14 #include "base/observer_list.h"
  15 #include "base/threading/non_thread_safe.h"
  16 #include "base/threading/thread.h"
  17 #include "net/base/backoff_entry.h"
  18 #include "remoting/host/client_session.h"
  19 #include "remoting/host/host_status_monitor.h"
  20 #include "remoting/host/host_status_observer.h"
  21 #include "remoting/protocol/authenticator.h"
  22 #include "remoting/protocol/connection_to_client.h"
  23 #include "remoting/protocol/pairing_registry.h"
  24 #include "remoting/protocol/session_manager.h"
  25
  26 namespace base {
  27 class SingleThreadTaskRunner;
  28 }  // namespace base
  29
  30 namespace remoting {
  31
  32 namespace protocol {
  33 class InputStub;
  34 class SessionConfig;
  35 class CandidateSessionConfig;
  36 }  // namespace protocol
  37
  38 class DesktopEnvironmentFactory;
  39
  40 // A class to implement the functionality of a host process.
  41 //
  42 // Here's the work flow of this class:
  43 // 1. We should load the saved GAIA ID token or if this is the first
  44 //    time the host process runs we should prompt user for the
  45 //    credential. We will use this token or credentials to authenicate
  46 //    and register the host.
  47 //
  48 // 2. We listen for incoming connection using libjingle. We will create
  49 //    a ConnectionToClient object that wraps around linjingle for transport.
  50 //    A VideoScheduler is created with an Encoder and a webrtc::ScreenCapturer.
  51 //    A ConnectionToClient is added to the ScreenRecorder for transporting
  52 //    the screen captures. An InputStub is created and registered with the
  53 //    ConnectionToClient to receive mouse / keyboard events from the remote
  54 //    client.
  55 //    After we have done all the initialization we'll start the ScreenRecorder.
  56 //    We'll then enter the running state of the host process.
  57 //
  58 // 3. When the user is disconnected, we will pause the ScreenRecorder
  59 //    and try to terminate the threads we have created. This will allow
  60 //    all pending tasks to complete. After all of that completed we
  61 //    return to the idle state. We then go to step (2) if there a new
  62 //    incoming connection.
  63 class ChromotingHost : public base::NonThreadSafe,
  64                        public ClientSession::EventHandler,
  65                        public protocol::SessionManager::Listener,
  66                        public HostStatusMonitor {
  67  public:
  68   // Both |signal_strategy| and |desktop_environment_factory| should outlive
  69   // this object.
  70   ChromotingHost(
  71       SignalStrategy* signal_strategy,
  72       DesktopEnvironmentFactory* desktop_environment_factory,
  73       scoped_ptr<protocol::SessionManager> session_manager,
  74       scoped_refptr<base::SingleThreadTaskRunner> audio_task_runner,
  75       scoped_refptr<base::SingleThreadTaskRunner> input_task_runner,
  76       scoped_refptr<base::SingleThreadTaskRunner> video_capture_task_runner,
  77       scoped_refptr<base::SingleThreadTaskRunner> video_encode_task_runner,
  78       scoped_refptr<base::SingleThreadTaskRunner> network_task_runner,
  79       scoped_refptr<base::SingleThreadTaskRunner> ui_task_runner);
  80   virtual ~ChromotingHost();
  81
  82   // Asynchronously starts the host.
  83   //
  84   // After this is invoked, the host process will connect to the talk
  85   // network and start listening for incoming connections.
  86   //
  87   // This method can only be called once during the lifetime of this object.
  88   void Start(const std::string& host_owner);
  89
  90   // HostStatusMonitor interface.
  91   virtual void AddStatusObserver(HostStatusObserver* observer) OVERRIDE;
  92   virtual void RemoveStatusObserver(HostStatusObserver* observer) OVERRIDE;
  93
  94   // This method may be called only from
  95   // HostStatusObserver::OnClientAuthenticated() to reject the new
  96   // client.
  97   void RejectAuthenticatingClient();
  98
  99   // Sets the authenticator factory to use for incoming
 100   // connections. Incoming connections are rejected until
 101   // authenticator factory is set. Must be called on the network
 102   // thread after the host is started. Must not be called more than
 103   // once per host instance because it may not be safe to delete
 104   // factory before all authenticators it created are deleted.
 105   void SetAuthenticatorFactory(
 106       scoped_ptr<protocol::AuthenticatorFactory> authenticator_factory);
 107
 108   // Enables/disables curtaining when one or more clients are connected.
 109   // Takes immediate effect if clients are already connected.
 110   void SetEnableCurtaining(bool enable);
 111
 112   // Sets the maximum duration of any session. By default, a session has no
 113   // maximum duration.
 114   void SetMaximumSessionDuration(const base::TimeDelta& max_session_duration);
 115
 116   ////////////////////////////////////////////////////////////////////////////
 117   // ClientSession::EventHandler implementation.
 118   virtual void OnSessionAuthenticating(ClientSession* client) OVERRIDE;
 119   virtual bool OnSessionAuthenticated(ClientSession* client) OVERRIDE;
 120   virtual void OnSessionChannelsConnected(ClientSession* client) OVERRIDE;
 121   virtual void OnSessionAuthenticationFailed(ClientSession* client) OVERRIDE;
 122   virtual void OnSessionClosed(ClientSession* session) OVERRIDE;
 123   virtual void OnSessionSequenceNumber(ClientSession* session,
 124                                        int64 sequence_number) OVERRIDE;
 125   virtual void OnSessionRouteChange(
 126       ClientSession* session,
 127       const std::string& channel_name,
 128       const protocol::TransportRoute& route) OVERRIDE;
 129
 130   // SessionManager::Listener implementation.
 131   virtual void OnSessionManagerReady() OVERRIDE;
 132   virtual void OnIncomingSession(
 133       protocol::Session* session,
 134       protocol::SessionManager::IncomingSessionResponse* response) OVERRIDE;
 135
 136   // Sets desired configuration for the protocol. Must be called before Start().
 137   void set_protocol_config(scoped_ptr<protocol::CandidateSessionConfig> config);
 138
 139   base::WeakPtr<ChromotingHost> AsWeakPtr() {
 140     return weak_factory_.GetWeakPtr();
 141   }
 142
 143   // The host uses a pairing registry to generate and store pairing information
 144   // for clients for PIN-less authentication.
 145   scoped_refptr<protocol::PairingRegistry> pairing_registry() const {
 146     return pairing_registry_;
 147   }
 148   void set_pairing_registry(
 149       scoped_refptr<protocol::PairingRegistry> pairing_registry) {
 150     pairing_registry_ = pairing_registry;
 151   }
 152
 153  private:
 154   friend class ChromotingHostTest;
 155
 156   typedef std::list<ClientSession*> ClientList;
 157
 158   // Immediately disconnects all active clients. Host-internal components may
 159   // shutdown asynchronously, but the caller is guaranteed not to receive
 160   // callbacks for disconnected clients after this call returns.
 161   void DisconnectAllClients();
 162
 163   // Unless specified otherwise all members of this class must be
 164   // used on the network thread only.
 165
 166   // Parameters specified when the host was created.
 167   DesktopEnvironmentFactory* desktop_environment_factory_;
 168   scoped_ptr<protocol::SessionManager> session_manager_;
 169   scoped_refptr<base::SingleThreadTaskRunner> audio_task_runner_;
 170   scoped_refptr<base::SingleThreadTaskRunner> input_task_runner_;
 171   scoped_refptr<base::SingleThreadTaskRunner> video_capture_task_runner_;
 172   scoped_refptr<base::SingleThreadTaskRunner> video_encode_task_runner_;
 173   scoped_refptr<base::SingleThreadTaskRunner> network_task_runner_;
 174   scoped_refptr<base::SingleThreadTaskRunner> ui_task_runner_;
 175
 176   // Connection objects.
 177   SignalStrategy* signal_strategy_;
 178
 179   // Must be used on the network thread only.
 180   ObserverList<HostStatusObserver> status_observers_;
 181
 182   // The connections to remote clients.
 183   ClientList clients_;
 184
 185   // True if the host has been started.
 186   bool started_;
 187
 188   // Configuration of the protocol.
 189   scoped_ptr<protocol::CandidateSessionConfig> protocol_config_;
 190
 191   // Login backoff state.
 192   net::BackoffEntry login_backoff_;
 193
 194   // Flags used for RejectAuthenticatingClient().
 195   bool authenticating_client_;
 196   bool reject_authenticating_client_;
 197
 198   // True if the curtain mode is enabled.
 199   bool enable_curtaining_;
 200
 201   // The maximum duration of any session.
 202   base::TimeDelta max_session_duration_;
 203
 204   // The pairing registry for PIN-less authentication.
 205   scoped_refptr<protocol::PairingRegistry> pairing_registry_;
 206
 207   base::WeakPtrFactory<ChromotingHost> weak_factory_;
 208
 209   DISALLOW_COPY_AND_ASSIGN(ChromotingHost);
 210 };
 211
 212 }  // namespace remoting
 213
 214 #endif  // REMOTING_HOST_CHROMOTING_HOST_H_