remoting/webapp/base/js/dns_blackhole_checker.js

   1 // Copyright 2015 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 'use strict';
   6
   7 /** @suppress {duplicate} */
   8 var remoting = remoting || {};
   9
  10 (function() {
  11
  12 /** @enum */
  13 var BlackholeState = {
  14   PENDING: 0,
  15   OPEN: 1,
  16   BLOCKED: 2
  17 };
  18
  19 /**
  20  * A SignalStrategy wrapper that performs DNS blackhole check.
  21  *
  22  * @param {remoting.SignalStrategy} signalStrategy
  23  * @constructor
  24  * @implements {remoting.SignalStrategy}
  25  */
  26 remoting.DnsBlackholeChecker = function(signalStrategy) {
  27   /** @private */
  28   this.signalStrategy_ = signalStrategy;
  29   this.signalStrategy_.setStateChangedCallback(
  30       this.onWrappedSignalStrategyStateChanged_.bind(this));
  31
  32   /** @private {?function(remoting.SignalStrategy.State):void} */
  33   this.onStateChangedCallback_ = null;
  34
  35   /** @private */
  36   this.state_ = remoting.SignalStrategy.State.NOT_CONNECTED;
  37
  38   /** @private */
  39   this.blackholeState_ = BlackholeState.PENDING;
  40
  41   /** @private {?remoting.Xhr} */
  42   this.xhr_ = null;
  43
  44   /** @const @private */
  45   this.url_ =
  46       remoting.settings.TALK_GADGET_URL + '/oauth/chrome-remote-desktop-client';
  47 };
  48
  49 /**
  50  * @param {?function(remoting.SignalStrategy.State):void} onStateChangedCallback
  51  *   Callback to call on state change.
  52  */
  53 remoting.DnsBlackholeChecker.prototype.setStateChangedCallback = function(
  54     onStateChangedCallback) {
  55   this.onStateChangedCallback_ = onStateChangedCallback;
  56 };
  57
  58 /**
  59  * @param {?function(Element):void} onIncomingStanzaCallback Callback to call on
  60  *     incoming messages.
  61  */
  62 remoting.DnsBlackholeChecker.prototype.setIncomingStanzaCallback =
  63     function(onIncomingStanzaCallback) {
  64   this.signalStrategy_.setIncomingStanzaCallback(onIncomingStanzaCallback);
  65 };
  66
  67 /** @return {remoting.SignalStrategy.Type} The signal strategy type. */
  68 remoting.DnsBlackholeChecker.prototype.getType = function() {
  69   return this.signalStrategy_.getType();
  70 };
  71
  72 /**
  73  * @param {string} server
  74  * @param {string} username
  75  * @param {string} authToken
  76  */
  77 remoting.DnsBlackholeChecker.prototype.connect = function(server,
  78                                                           username,
  79                                                           authToken) {
  80   console.assert(this.onStateChangedCallback_ != null,
  81                  'No state change callback registered.');
  82
  83   this.signalStrategy_.connect(server, username, authToken);
  84
  85   this.xhr_ = new remoting.Xhr({
  86     method: 'GET',
  87     url: this.url_
  88   });
  89   this.xhr_.start().then(this.onHttpRequestDone_.bind(this));
  90 };
  91
  92 remoting.DnsBlackholeChecker.prototype.getState = function() {
  93   return this.state_;
  94 };
  95
  96 remoting.DnsBlackholeChecker.prototype.getError = function() {
  97   if (this.blackholeState_ == BlackholeState.BLOCKED) {
  98     return new remoting.Error(remoting.Error.Tag.NOT_AUTHORIZED);
  99   }
 100
 101   return this.signalStrategy_.getError();
 102 };
 103
 104 remoting.DnsBlackholeChecker.prototype.getJid = function() {
 105   console.assert(this.state_ == remoting.SignalStrategy.State.CONNECTED,
 106                 'getJid() called in state ' + this.state_ + '.');
 107   return this.signalStrategy_.getJid();
 108 };
 109
 110 remoting.DnsBlackholeChecker.prototype.dispose = function() {
 111   this.xhr_ = null;
 112   base.dispose(this.signalStrategy_);
 113   this.setState_(remoting.SignalStrategy.State.CLOSED);
 114 };
 115
 116 /** @param {string} message */
 117 remoting.DnsBlackholeChecker.prototype.sendMessage = function(message) {
 118   console.assert(this.state_ == remoting.SignalStrategy.State.CONNECTED,
 119                 'sendMessage() called in state ' + this.state_ + '.');
 120   this.signalStrategy_.sendMessage(message);
 121 };
 122
 123 /** @param {remoting.SignalStrategy.State} state */
 124 remoting.DnsBlackholeChecker.prototype.onWrappedSignalStrategyStateChanged_ =
 125     function(state) {
 126   switch (this.blackholeState_) {
 127     case BlackholeState.PENDING:
 128       // Stay in HANDSHAKE state if we are still waiting for the HTTP request.
 129       if (state != remoting.SignalStrategy.State.CONNECTED) {
 130         this.setState_(state);
 131       }
 132       break;
 133     case BlackholeState.OPEN:
 134       this.setState_(state);
 135       break;
 136     case BlackholeState.BLOCKED:
 137       // In case DNS blackhole is active the external state stays FAILED.
 138       break;
 139   }
 140 };
 141
 142 /**
 143  * @param {!remoting.Xhr.Response} response
 144  * @private
 145  */
 146 remoting.DnsBlackholeChecker.prototype.onHttpRequestDone_ = function(response) {
 147   if (this.xhr_ == null) {
 148     // This happens when the dispose() method is called while a
 149     // request is pending.
 150     return;
 151   }
 152
 153   this.xhr_ = null;
 154   if (response.status >= 200 && response.status <= 299) {
 155     console.log("DNS blackhole check succeeded.");
 156     this.blackholeState_ = BlackholeState.OPEN;
 157     if (this.signalStrategy_.getState() ==
 158         remoting.SignalStrategy.State.CONNECTED) {
 159       this.setState_(remoting.SignalStrategy.State.CONNECTED);
 160     }
 161   } else {
 162     console.error("DNS blackhole check failed: " + response.status + " " +
 163                   response.statusText + ". Response URL: " +
 164                   response.url + ". Response Text: " +
 165                   response.getText());
 166     this.blackholeState_ = BlackholeState.BLOCKED;
 167     base.dispose(this.signalStrategy_);
 168     this.setState_(remoting.SignalStrategy.State.FAILED);
 169   }
 170 };
 171
 172 /**
 173  * @param {remoting.SignalStrategy.State} newState
 174  * @private
 175  */
 176 remoting.DnsBlackholeChecker.prototype.setState_ = function(newState) {
 177   if (this.state_ != newState) {
 178     this.state_ = newState;
 179     this.onStateChangedCallback_(this.state_);
 180   }
 181 };
 182
 183 }());