XMPP implementation in JavaScript.

remoting/webapp/xmpp_connection.js

+// Copyright 2014 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.
+
+'use strict';
+
+/** @suppress {duplicate} */
+var remoting = remoting || {};
+
+/**
+ * A connection to an XMPP server.
+ *
+ * TODO(sergeyu): Chrome provides two APIs for TCP sockets: chrome.socket and
+ * chrome.sockets.tcp . chrome.socket is deprecated but it's still used here
+ * because TLS support in chrome.sockets.tcp is currently broken, see
+ * crbug.com/403076 .
+ *
+ * @param {function(remoting.XmppConnection.State):void} onStateChangedCallback
+ *   Callback to call on state change.
+ * @param {function(Element):void} onIncomingStanzaCallback Callback to call to
+ *   handle incoming messages.
+ * @constructor
+ * @implements {base.Disposable}
+ */
+remoting.XmppConnection =
+    function(onStateChangedCallback, onIncomingStanzaCallback) {
+  /** @private */
+  this.server_ = '';
+  /** @private */
+  this.port_ = 0;
+  /** @private */
+  this.onStateChangedCallback_ = onStateChangedCallback;
+  /** @private */
+  this.onIncomingStanzaCallback_ = onIncomingStanzaCallback;
+  /** @private */
+  this.socketId_ = -1;
+  /** @private */
+  this.state_ = remoting.XmppConnection.State.NOT_CONNECTED;
+  /** @private */
+  this.readPending_ = false;
+  /** @private */
+  this.sendPending_ = false;
+  /** @private */
+  this.startTlsPending_ = false;
+  /** @type {Array.<ArrayBuffer>} @private */
+  this.sendQueue_ = [];
+  /** @type {remoting.XmppLoginHandler} @private*/
+  this.loginHandler_ = null;
+  /** @type {remoting.XmppStreamParser} @private*/
+  this.streamParser_ = null;
+  /** @private */
+  this.jid_ = '';
+  /** @private */
+  this.error_ = remoting.Error.NONE;
+};
+
+/**
+ * @enum {number} XmppConnection states. Possible state transitions:
+ *    NOT_CONNECTED -> CONNECTING (connect() called).
+ *    CONNECTING -> HANDSHAKE (connected successfully).
+ *    HANDSHAKE -> CONNECTED (authenticated successfully).
+ *    CONNECTING -> FAILED (connection failed).
+ *    HANDSHAKE -> FAILED (authentication failed).
+ *    * -> CLOSED (dispose() called).
+ */
+remoting.XmppConnection.State = {
+  NOT_CONNECTED: 0,
+  CONNECTING: 1,
+  HANDSHAKE: 2,
+  CONNECTED: 3,
+  FAILED: 4,
+  CLOSED: 5
+};
+
+/**
+ * @param {string} server
+ * @param {string} username
+ * @param {string} authToken
+ */
+remoting.XmppConnection.prototype.connect =
+    function(server, username, authToken) {
+  base.debug.assert(this.state_ == remoting.XmppConnection.State.NOT_CONNECTED);
+
+  this.error_ = remoting.Error.NONE;
+  var hostnameAndPort = server.split(':', 2);
+  this.server_ = hostnameAndPort[0];
+  this.port_ =
+      (hostnameAndPort.length == 2) ? parseInt(hostnameAndPort[1], 10) : 5222;
+
+  // The server name is passed as to attribute in the <stream>. When connecting
+  // to talk.google.com it affects the certificate the server will use for TLS:
+  // talk.google.com uses gmail certificate when specified server is gmail.com
+  // or googlemail.com and google.com cert otherwise. In the same time it
+  // doesn't accept talk.google.com as target server. Here we use google.com
+  // server name when authenticating to talk.google.com. This ensures that the
+  // server will use google.com cert which will be accepted by the TLS
+  // implementation in Chrome (TLS API doesn't allow specifying domain other
+  // than the one that was passed to connect()).
+  var xmppServer = this.server_;
+  if (xmppServer == 'talk.google.com')
+    xmppServer = 'google.com';
+
+  /** @type {remoting.XmppLoginHandler} */
+  this.loginHandler_ =
+      new remoting.XmppLoginHandler(xmppServer, username, authToken,
+                                    this.sendInternal_.bind(this),
+                                    this.startTls_.bind(this),
+                                    this.onHandshakeDone_.bind(this),
+                                    this.onError_.bind(this));
+  chrome.socket.create("tcp", {}, this.onSocketCreated_.bind(this));
+  this.setState_(remoting.XmppConnection.State.CONNECTING);
+};
+
+/** @param {string} message */
+remoting.XmppConnection.prototype.sendMessage = function(message) {
+  base.debug.assert(this.state_ == remoting.XmppConnection.State.CONNECTED);
+  this.sendInternal_(message);
+};
+
+/** @return {remoting.XmppConnection.State} Current state */
+remoting.XmppConnection.prototype.getState = function() {
+  return this.state_;
+};
+
+/** @return {remoting.Error} Error when in FAILED state. */
+remoting.XmppConnection.prototype.getError = function() {
+  return this.error_;
+};
+
+/** @return {string} Current JID when in CONNECTED state. */
+remoting.XmppConnection.prototype.getJid = function() {
+  return this.jid_;
+};
+
+remoting.XmppConnection.prototype.dispose = function() {
+  this.closeSocket_();
+  this.setState_(remoting.XmppConnection.State.CLOSED);
+};
+
+/**
+ * @param {chrome.socket.CreateInfo} createInfo
+ * @private
+ */
+remoting.XmppConnection.prototype.onSocketCreated_ = function(createInfo) {
+  // Check if connection was destroyed.
+  if (this.state_ != remoting.XmppConnection.State.CONNECTING) {
+    chrome.socket.destroy(createInfo.socketId);
+    return;
+  }
+
+  this.socketId_ = createInfo.socketId;
+
+  chrome.socket.connect(this.socketId_,
+                        this.server_,
+                        this.port_,
+                        this.onSocketConnected_.bind(this));
+};
+
+/**
+ * @param {number} result
+ * @private
+ */
+remoting.XmppConnection.prototype.onSocketConnected_ = function(result) {
+  // Check if connection was destroyed.
+  if (this.state_ != remoting.XmppConnection.State.CONNECTING) {
+    return;
+  }
+
+  if (result != 0) {
+    this.onError_(remoting.Error.NETWORK_FAILURE,
+                  'Failed to connect to ' + this.server_ + ': ' +  result);
+    return;
+  }
+
+  this.setState_(remoting.XmppConnection.State.HANDSHAKE);
+
+  this.tryRead_();
+  this.loginHandler_.start();
+};
+
+/**
+ * @private
+ */
+remoting.XmppConnection.prototype.tryRead_ = function() {
+  base.debug.assert(!this.readPending_);
+  base.debug.assert(this.state_ == remoting.XmppConnection.State.HANDSHAKE ||
+                    this.state_ == remoting.XmppConnection.State.CONNECTED);
+  base.debug.assert(!this.startTlsPending_);
+
+  this.readPending_ = true;
+  chrome.socket.read(this.socketId_, this.onRead_.bind(this));
+};
+
+/**
+ * @param {chrome.socket.ReadInfo} readInfo
+ * @private
+ */
+remoting.XmppConnection.prototype.onRead_ = function(readInfo) {
+  base.debug.assert(this.readPending_);
+  this.readPending_ = false;
+
+  // Check if the socket was closed while reading.
+  if (this.state_ != remoting.XmppConnection.State.HANDSHAKE &&
+      this.state_ != remoting.XmppConnection.State.CONNECTED) {
+    return;
+  }
+
+  if (readInfo.resultCode < 0) {
+    this.onError_(remoting.Error.NETWORK_FAILURE,
+                  'Failed to receive from XMPP socket: ' + readInfo.resultCode);
+    return;
+  }
+
+  if (this.state_ == remoting.XmppConnection.State.HANDSHAKE) {
+    this.loginHandler_.onDataReceived(readInfo.data);
+  } else if (this.state_ == remoting.XmppConnection.State.CONNECTED) {
+    this.streamParser_.appendData(readInfo.data);
+  }
+
+  if (!this.startTlsPending_) {
+    this.tryRead_();
+  }
+};
+
+/**
+ * @param {string} text
+ * @private
+ */
+remoting.XmppConnection.prototype.sendInternal_ = function(text) {
+  this.sendQueue_.push(base.encodeUtf8(text));
+  this.doSend_();
+};
+
+/**
+ * @private
+ */
+remoting.XmppConnection.prototype.doSend_ = function() {
+  if (this.sendPending_ || this.sendQueue_.length == 0) {
+    return;
+  }
+
+  var data = this.sendQueue_[0]
+  this.sendPending_ = true;
+  chrome.socket.write(this.socketId_, data, this.onWrite_.bind(this));
+};
+
+/**
+ * @param {chrome.socket.WriteInfo} writeInfo
+ * @private
+ */
+remoting.XmppConnection.prototype.onWrite_ = function(writeInfo) {
+  base.debug.assert(this.sendPending_);
+  this.sendPending_ = false;
+
+  // Ignore write() result if the socket was closed.
+  if (this.state_ != remoting.XmppConnection.State.HANDSHAKE &&
+      this.state_ != remoting.XmppConnection.State.CONNECTED) {
+    return;
+  }
+
+  if (writeInfo.bytesWritten < 0) {
+    this.onError_(remoting.Error.NETWORK_FAILURE,
+                  'TCP write failed with error ' + writeInfo.bytesWritten);
+    return;
+  }
+
+  base.debug.assert(this.sendQueue_.length > 0);
+
+  var data = this.sendQueue_[0]
+  base.debug.assert(writeInfo.bytesWritten <= data.byteLength);
+  if (writeInfo.bytesWritten == data.byteLength) {
+    this.sendQueue_.shift();
+  } else {
+    this.sendQueue_[0] = data.slice(data.byteLength - writeInfo.bytesWritten);
+  }
+
+  this.doSend_();
+};
+
+/**
+ * @private
+ */
+remoting.XmppConnection.prototype.startTls_ = function() {
+  base.debug.assert(!this.readPending_);
+  base.debug.assert(!this.startTlsPending_);
+
+  this.startTlsPending_ = true;
+  chrome.socket.secure(
+      this.socketId_, {}, this.onTlsStarted_.bind(this));
+}
+
+/**
+ * @param {number} resultCode
+ * @private
+ */
+remoting.XmppConnection.prototype.onTlsStarted_ = function(resultCode) {
+  base.debug.assert(this.startTlsPending_);
+  this.startTlsPending_ = false;
+
+  if (resultCode < 0) {
+    this.onError_(remoting.Error.NETWORK_FAILURE,
+                  'Failed to start TLS: ' + resultCode);
+    return;
+  }
+
+  this.tryRead_();
+  this.loginHandler_.onTlsStarted();
+};
+
+/**
+ * @param {string} jid
+ * @param {remoting.XmppStreamParser} streamParser
+ * @private
+ */
+remoting.XmppConnection.prototype.onHandshakeDone_ =
+    function(jid, streamParser) {
+  this.jid_ = jid;
+  this.streamParser_ = streamParser;
+  this.streamParser_.setCallbacks(this.onIncomingStanzaCallback_,
+                                  this.onParserError_.bind(this));
+  this.setState_(remoting.XmppConnection.State.CONNECTED);
+};
+
+/**
+ * @param {string} text
+ * @private
+ */
+remoting.XmppConnection.prototype.onParserError_ = function(text) {
+  this.onError_(remoting.Error.UNEXPECTED, text);
+}
+
+/**
+ * @param {remoting.Error} error
+ * @param {string} text
+ * @private
+ */
+remoting.XmppConnection.prototype.onError_ = function(error, text) {
+  console.error(text);
+  this.error_ = error;
+  this.closeSocket_();
+  this.setState_(remoting.XmppConnection.State.FAILED);
+};
+
+/**
+ * @private
+ */
+remoting.XmppConnection.prototype.closeSocket_ = function() {
+  if (this.socketId_ != -1) {
+    chrome.socket.destroy(this.socketId_);
+    this.socketId_ = -1;
+  }
+};
+
+/**
+ * @param {remoting.XmppConnection.State} newState
+ * @private
+ */
+remoting.XmppConnection.prototype.setState_ = function(newState) {
+  if (this.state_ != newState) {
+    this.state_ = newState;
+    this.onStateChangedCallback_(this.state_);
+  }
+};