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
  45 /**
  46  * @const
  47  * @private
  48  */
  49 remoting.DnsBlackholeChecker.URL_TO_REQUEST_ =
  50     "https://chromoting-client.talkgadget.google.com/talkgadget/oauth/" +
  51     "chrome-remote-desktop-client";
  52
  53 /**
  54  * @param {?function(remoting.SignalStrategy.State):void} onStateChangedCallback
  55  *   Callback to call on state change.
  56  */
  57 remoting.DnsBlackholeChecker.prototype.setStateChangedCallback = function(
  58     onStateChangedCallback) {
  59   this.onStateChangedCallback_ = onStateChangedCallback;
  60 };
  61
  62 /**
  63  * @param {?function(Element):void} onIncomingStanzaCallback Callback to call on
  64  *     incoming messages.
  65  */
  66 remoting.DnsBlackholeChecker.prototype.setIncomingStanzaCallback =
  67     function(onIncomingStanzaCallback) {
  68   this.signalStrategy_.setIncomingStanzaCallback(onIncomingStanzaCallback);
  69 };
  70
  71 /** @return {remoting.SignalStrategy.Type} The signal strategy type. */
  72 remoting.DnsBlackholeChecker.prototype.getType = function() {
  73   return this.signalStrategy_.getType();
  74 };
  75
  76 /**
  77  * @param {string} server
  78  * @param {string} username
  79  * @param {string} authToken
  80  */
  81 remoting.DnsBlackholeChecker.prototype.connect = function(server,
  82                                                           username,
  83                                                           authToken) {
  84   console.assert(this.onStateChangedCallback_ != null,
  85                  'No state change callback registered.');
  86
  87   this.signalStrategy_.connect(server, username, authToken);
  88
  89   this.xhr_ = new remoting.Xhr({
  90     method: 'GET',
  91     url: remoting.DnsBlackholeChecker.URL_TO_REQUEST_
  92   });
  93   this.xhr_.start().then(this.onHttpRequestDone_.bind(this));
  94 };
  95
  96 remoting.DnsBlackholeChecker.prototype.getState = function() {
  97   return this.state_;
  98 };
  99
 100 remoting.DnsBlackholeChecker.prototype.getError = function() {
 101   if (this.blackholeState_ == BlackholeState.BLOCKED) {
 102     return new remoting.Error(remoting.Error.Tag.NOT_AUTHORIZED);
 103   }
 104
 105   return this.signalStrategy_.getError();
 106 };
 107
 108 remoting.DnsBlackholeChecker.prototype.getJid = function() {
 109   console.assert(this.state_ == remoting.SignalStrategy.State.CONNECTED,
 110                 'getJid() called in state ' + this.state_ + '.');
 111   return this.signalStrategy_.getJid();
 112 };
 113
 114 remoting.DnsBlackholeChecker.prototype.dispose = function() {
 115   this.xhr_ = null;
 116   base.dispose(this.signalStrategy_);
 117   this.setState_(remoting.SignalStrategy.State.CLOSED);
 118 };
 119
 120 remoting.DnsBlackholeChecker.prototype.sendConnectionSetupResults = function(
 121     logger) {
 122   this.signalStrategy_.sendConnectionSetupResults(logger);
 123 };
 124
 125 /** @param {string} message */
 126 remoting.DnsBlackholeChecker.prototype.sendMessage = function(message) {
 127   console.assert(this.state_ == remoting.SignalStrategy.State.CONNECTED,
 128                 'sendMessage() called in state ' + this.state_ + '.');
 129   this.signalStrategy_.sendMessage(message);
 130 };
 131
 132 /** @param {remoting.SignalStrategy.State} state */
 133 remoting.DnsBlackholeChecker.prototype.onWrappedSignalStrategyStateChanged_ =
 134     function(state) {
 135   switch (this.blackholeState_) {
 136     case BlackholeState.PENDING:
 137       // Stay in HANDSHAKE state if we are still waiting for the HTTP request.
 138       if (state != remoting.SignalStrategy.State.CONNECTED) {
 139         this.setState_(state);
 140       }
 141       break;
 142     case BlackholeState.OPEN:
 143       this.setState_(state);
 144       break;
 145     case BlackholeState.BLOCKED:
 146       // In case DNS blackhole is active the external state stays FAILED.
 147       break;
 148   }
 149 };
 150
 151 /**
 152  * @param {!remoting.Xhr.Response} response
 153  * @private
 154  */
 155 remoting.DnsBlackholeChecker.prototype.onHttpRequestDone_ = function(response) {
 156   if (this.xhr_ == null) {
 157     // This happens when the dispose() method is called while a
 158     // request is pending.
 159     return;
 160   }
 161
 162   this.xhr_ = null;
 163   if (response.status >= 200 && response.status <= 299) {
 164     console.log("DNS blackhole check succeeded.");
 165     this.blackholeState_ = BlackholeState.OPEN;
 166     if (this.signalStrategy_.getState() ==
 167         remoting.SignalStrategy.State.CONNECTED) {
 168       this.setState_(remoting.SignalStrategy.State.CONNECTED);
 169     }
 170   } else {
 171     console.error("DNS blackhole check failed: " + response.status + " " +
 172                   response.statusText + ". Response URL: " +
 173                   response.url + ". Response Text: " +
 174                   response.getText());
 175     this.blackholeState_ = BlackholeState.BLOCKED;
 176     base.dispose(this.signalStrategy_);
 177     this.setState_(remoting.SignalStrategy.State.FAILED);
 178   }
 179 };
 180
 181 /**
 182  * @param {remoting.SignalStrategy.State} newState
 183  * @private
 184  */
 185 remoting.DnsBlackholeChecker.prototype.setState_ = function(newState) {
 186   if (this.state_ != newState) {
 187     this.state_ = newState;
 188     this.onStateChangedCallback_(this.state_);
 189   }
 190 };
 191
 192 }());