Add m-esr52 at 52.6.0

1 files changed, 875 insertions, 0 deletions

diff --git a/netwerk/dns/mdns/libmdns/fallback/MulticastDNS.jsm b/netwerk/dns/mdns/libmdns/fallback/MulticastDNS.jsm
new file mode 100644
index 000000000..f43dfd5f8
--- /dev/null
+++ b/netwerk/dns/mdns/libmdns/fallback/MulticastDNS.jsm
@@ -0,0 +1,875 @@
+/* -*- Mode: js; js-indent-level: 2; indent-tabs-mode: nil; tab-width: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+/* jshint esnext: true, moz: true */
+
+'use strict';
+
+this.EXPORTED_SYMBOLS = ['MulticastDNS'];
+
+const { classes: Cc, interfaces: Ci, utils: Cu, results: Cr } = Components;
+
+Cu.import('resource://gre/modules/Services.jsm');
+Cu.import('resource://gre/modules/Timer.jsm');
+Cu.import('resource://gre/modules/XPCOMUtils.jsm');
+
+Cu.import('resource://gre/modules/DNSPacket.jsm');
+Cu.import('resource://gre/modules/DNSRecord.jsm');
+Cu.import('resource://gre/modules/DNSResourceRecord.jsm');
+Cu.import('resource://gre/modules/DNSTypes.jsm');
+
+const NS_NETWORK_LINK_TOPIC = 'network:link-status-changed';
+
+let observerService     = Cc["@mozilla.org/observer-service;1"]
+                            .getService(Components.interfaces.nsIObserverService);
+let networkInfoService  = Cc['@mozilla.org/network-info-service;1']
+                            .createInstance(Ci.nsINetworkInfoService);
+
+const DEBUG = true;
+
+const MDNS_MULTICAST_GROUP = '224.0.0.251';
+const MDNS_PORT            = 5353;
+const DEFAULT_TTL          = 120;
+
+function debug(msg) {
+  dump('MulticastDNS: ' + msg + '\n');
+}
+
+function ServiceKey(svc) {
+  return "" + svc.serviceType.length + "/" + svc.serviceType + "|" +
+              svc.serviceName.length + "/" + svc.serviceName + "|" +
+              svc.port;
+}
+
+function TryGet(obj, name) {
+  try {
+    return obj[name];
+  } catch (err) {
+    return undefined;
+  }
+}
+
+function IsIpv4Address(addr) {
+  let parts = addr.split('.');
+  if (parts.length != 4) {
+    return false;
+  }
+  for (let part of parts) {
+    let partInt = Number.parseInt(part, 10);
+    if (partInt.toString() != part) {
+      return false;
+    }
+    if (partInt < 0 || partInt >= 256) {
+      return false;
+    }
+  }
+  return true;
+}
+
+class PublishedService {
+  constructor(attrs) {
+    this.serviceType = attrs.serviceType.replace(/\.$/, '');
+    this.serviceName = attrs.serviceName;
+    this.domainName = TryGet(attrs, 'domainName') || "local";
+    this.address = TryGet(attrs, 'address') || "0.0.0.0";
+    this.port = attrs.port;
+    this.serviceAttrs = _propertyBagToObject(TryGet(attrs, 'attributes') || {});
+    this.host = TryGet(attrs, 'host');
+    this.key = this.generateKey();
+    this.lastAdvertised = undefined;
+    this.advertiseTimer = undefined;
+  }
+
+  equals(svc) {
+    return (this.port == svc.port) &&
+           (this.serviceName == svc.serviceName) &&
+           (this.serviceType == svc.serviceType);
+  }
+
+  generateKey() {
+    return ServiceKey(this);
+  }
+
+  ptrMatch(name) {
+    return name == (this.serviceType + "." + this.domainName);
+  }
+
+  clearAdvertiseTimer() {
+    if (!this.advertiseTimer) {
+      return;
+    }
+    clearTimeout(this.advertiseTimer);
+    this.advertiseTimer = undefined;
+  }
+}
+
+class MulticastDNS {
+  constructor() {
+    this._listeners       = new Map();
+    this._sockets         = new Map();
+    this._services        = new Map();
+    this._discovered      = new Map();
+    this._querySocket     = undefined;
+    this._broadcastReceiverSocket = undefined;
+    this._broadcastTimer  = undefined;
+
+    this._networkLinkObserver = {
+      observe: (subject, topic, data) => {
+        DEBUG && debug(NS_NETWORK_LINK_TOPIC + '(' + data + '); Clearing list of previously discovered services');
+        this._discovered.clear();
+      }
+    };
+  }
+
+  _attachNetworkLinkObserver() {
+    if (this._networkLinkObserverTimeout) {
+      clearTimeout(this._networkLinkObserverTimeout);
+    }
+
+    if (!this._isNetworkLinkObserverAttached) {
+      DEBUG && debug('Attaching observer ' + NS_NETWORK_LINK_TOPIC);
+      observerService.addObserver(this._networkLinkObserver, NS_NETWORK_LINK_TOPIC, false);
+      this._isNetworkLinkObserverAttached = true;
+    }
+  }
+
+  _detachNetworkLinkObserver() {
+    if (this._isNetworkLinkObserverAttached) {
+      if (this._networkLinkObserverTimeout) {
+        clearTimeout(this._networkLinkObserverTimeout);
+      }
+
+      this._networkLinkObserverTimeout = setTimeout(() => {
+        DEBUG && debug('Detaching observer ' + NS_NETWORK_LINK_TOPIC);
+        observerService.removeObserver(this._networkLinkObserver, NS_NETWORK_LINK_TOPIC);
+        this._isNetworkLinkObserverAttached = false;
+        this._networkLinkObserverTimeout = null;
+      }, 5000);
+    }
+  }
+
+  startDiscovery(aServiceType, aListener) {
+    DEBUG && debug('startDiscovery("' + aServiceType + '")');
+    let { serviceType } = _parseServiceDomainName(aServiceType);
+
+    this._attachNetworkLinkObserver();
+    this._addServiceListener(serviceType, aListener);
+
+    try {
+      this._query(serviceType + '.local');
+      aListener.onDiscoveryStarted(serviceType);
+    } catch (e) {
+      DEBUG && debug('startDiscovery("' + serviceType + '") FAILED: ' + e);
+      this._removeServiceListener(serviceType, aListener);
+      aListener.onStartDiscoveryFailed(serviceType, Cr.NS_ERROR_FAILURE);
+    }
+  }
+
+  stopDiscovery(aServiceType, aListener) {
+    DEBUG && debug('stopDiscovery("' + aServiceType + '")');
+    let { serviceType } = _parseServiceDomainName(aServiceType);
+
+    this._detachNetworkLinkObserver();
+    this._removeServiceListener(serviceType, aListener);
+
+    aListener.onDiscoveryStopped(serviceType);
+
+    this._checkCloseSockets();
+  }
+
+  resolveService(aServiceInfo, aListener) {
+    DEBUG && debug('resolveService(): ' + aServiceInfo.serviceName);
+
+    // Address info is already resolved during discovery
+    setTimeout(() => aListener.onServiceResolved(aServiceInfo));
+  }
+
+  registerService(aServiceInfo, aListener) {
+    DEBUG && debug('registerService(): ' + aServiceInfo.serviceName);
+
+    // Initialize the broadcast receiver socket in case it
+    // hasn't already been started so we can listen for
+    // multicast queries/announcements on all interfaces.
+    this._getBroadcastReceiverSocket();
+
+    for (let name of ['port', 'serviceName', 'serviceType']) {
+      if (!TryGet(aServiceInfo, name)) {
+        aListener.onRegistrationFailed(aServiceInfo, Cr.NS_ERROR_FAILURE);
+        throw new Error('Invalid nsIDNSServiceInfo; Missing "' + name + '"');
+      }
+    }
+
+    let publishedService;
+    try {
+      publishedService = new PublishedService(aServiceInfo);
+    } catch (e) {
+      DEBUG && debug("Error constructing PublishedService: " + e + " - " + e.stack);
+      setTimeout(() => aListener.onRegistrationFailed(aServiceInfo, Cr.NS_ERROR_FAILURE));
+      return;
+    }
+
+    // Ensure such a service does not already exist.
+    if (this._services.get(publishedService.key)) {
+      setTimeout(() => aListener.onRegistrationFailed(aServiceInfo, Cr.NS_ERROR_FAILURE));
+      return;
+    }
+
+    // Make sure that the service addr is '0.0.0.0', or there is at least one
+    // socket open on the address the service is open on.
+    this._getSockets().then((sockets) => {
+      if (publishedService.address != '0.0.0.0' && !sockets.get(publishedService.address)) {
+        setTimeout(() => aListener.onRegistrationFailed(aServiceInfo, Cr.NS_ERROR_FAILURE));
+        return;
+      }
+
+      this._services.set(publishedService.key, publishedService);
+
+      // Service registered.. call onServiceRegistered on next tick.
+      setTimeout(() => aListener.onServiceRegistered(aServiceInfo));
+
+      // Set a timeout to start advertising the service too.
+      publishedService.advertiseTimer = setTimeout(() => {
+        this._advertiseService(publishedService.key, /* firstAdv = */ true);
+      });
+    });
+  }
+
+  unregisterService(aServiceInfo, aListener) {
+    DEBUG && debug('unregisterService(): ' + aServiceInfo.serviceName);
+
+    let serviceKey;
+    try {
+      serviceKey = ServiceKey(aServiceInfo);
+    } catch (e) {
+      setTimeout(() => aListener.onUnregistrationFailed(aServiceInfo, Cr.NS_ERROR_FAILURE));
+      return;
+    }
+
+    let publishedService = this._services.get(serviceKey);
+    if (!publishedService) {
+      setTimeout(() => aListener.onUnregistrationFailed(aServiceInfo, Cr.NS_ERROR_FAILURE));
+      return;
+    }
+
+    // Clear any advertise timeout for this published service.
+    publishedService.clearAdvertiseTimer();
+
+    // Delete the service from the service map.
+    if (!this._services.delete(serviceKey)) {
+      setTimeout(() => aListener.onUnregistrationFailed(aServiceInfo, Cr.NS_ERROR_FAILURE));
+      return;
+    }
+
+    // Check the broadcast timer again to rejig when it should run next.
+    this._checkStartBroadcastTimer();
+
+    // Check to see if sockets should be closed, and if so close them.
+    this._checkCloseSockets();
+
+    aListener.onServiceUnregistered(aServiceInfo);
+  }
+
+  _respondToQuery(serviceKey, message) {
+    let address = message.fromAddr.address;
+    let port = message.fromAddr.port;
+    DEBUG && debug('_respondToQuery(): key=' + serviceKey + ', fromAddr='
+                        + address + ":" + port);
+
+    let publishedService = this._services.get(serviceKey);
+    if (!publishedService) {
+      debug("_respondToQuery Could not find service (key=" + serviceKey + ")");
+      return;
+    }
+
+    DEBUG && debug('_respondToQuery(): key=' + serviceKey + ': SENDING RESPONSE');
+    this._advertiseServiceHelper(publishedService, {address,port});
+  }
+
+  _advertiseService(serviceKey, firstAdv) {
+    DEBUG && debug('_advertiseService(): key=' + serviceKey);
+    let publishedService = this._services.get(serviceKey);
+    if (!publishedService) {
+      debug("_advertiseService Could not find service to advertise (key=" + serviceKey + ")");
+      return;
+    }
+
+    publishedService.advertiseTimer = undefined;
+
+    this._advertiseServiceHelper(publishedService, null).then(() => {
+      // If first advertisement, re-advertise in 1 second.
+      // Otherwise, set the lastAdvertised time.
+      if (firstAdv) {
+        publishedService.advertiseTimer = setTimeout(() => {
+          this._advertiseService(serviceKey)
+        }, 1000);
+      } else {
+        publishedService.lastAdvertised = Date.now();
+        this._checkStartBroadcastTimer();
+      }
+    });
+  }
+
+  _advertiseServiceHelper(svc, target) {
+    if (!target) {
+      target = {address:MDNS_MULTICAST_GROUP, port:MDNS_PORT};
+    }
+
+    return this._getSockets().then((sockets) => {
+      sockets.forEach((socket, address) => {
+        if (svc.address == "0.0.0.0" || address == svc.address)
+        {
+          let packet = this._makeServicePacket(svc, [address]);
+          let data = packet.serialize();
+          try {
+            socket.send(target.address, target.port, data, data.length);
+          } catch (err) {
+            DEBUG && debug("Failed to send packet to "
+                            + target.address + ":" + target.port);
+          }
+        }
+      });
+    });
+  }
+
+  _cancelBroadcastTimer() {
+    if (!this._broadcastTimer) {
+      return;
+    }
+    clearTimeout(this._broadcastTimer);
+    this._broadcastTimer = undefined;
+  }
+
+  _checkStartBroadcastTimer() {
+    DEBUG && debug("_checkStartBroadcastTimer()");
+    // Cancel any existing broadcasting timer.
+    this._cancelBroadcastTimer();
+
+    let now = Date.now();
+
+    // Go through services and find services to broadcast.
+    let bcastServices = [];
+    let nextBcastWait = undefined;
+    for (let [serviceKey, publishedService] of this._services) {
+      // if lastAdvertised is undefined, service hasn't finished it's initial
+      // two broadcasts.
+      if (publishedService.lastAdvertised === undefined) {
+        continue;
+      }
+
+      // Otherwise, check lastAdvertised against now.
+      let msSinceAdv = now - publishedService.lastAdvertised;
+
+      // If msSinceAdv is more than 90% of the way to the TTL, advertise now.
+      if (msSinceAdv > (DEFAULT_TTL * 1000 * 0.9)) {
+        bcastServices.push(publishedService);
+        continue;
+      }
+
+      // Otherwise, calculate the next time to advertise for this service.
+      // We set that at 95% of the time to the TTL expiry.
+      let nextAdvWait = (DEFAULT_TTL * 1000 * 0.95) - msSinceAdv;
+      if (nextBcastWait === undefined || nextBcastWait > nextAdvWait) {
+        nextBcastWait = nextAdvWait;
+      }
+    }
+
+    // Schedule an immediate advertisement of all services to be advertised now.
+    for (let svc of bcastServices) {
+        svc.advertiseTimer = setTimeout(() => this._advertiseService(svc.key));
+    }
+
+    // Schedule next broadcast check for the next bcast time.
+    if (nextBcastWait !== undefined) {
+      DEBUG && debug("_checkStartBroadcastTimer(): Scheduling next check in " + nextBcastWait + "ms");
+      this._broadcastTimer = setTimeout(() => this._checkStartBroadcastTimer(), nextBcastWait);
+    }
+  }
+
+  _query(name) {
+    DEBUG && debug('query("' + name + '")');
+    let packet = new DNSPacket();
+    packet.setFlag('QR', DNS_QUERY_RESPONSE_CODES.QUERY);
+
+    // PTR Record
+    packet.addRecord('QD', new DNSRecord({
+      name: name,
+      recordType: DNS_RECORD_TYPES.PTR,
+      classCode: DNS_CLASS_CODES.IN,
+      cacheFlush: true
+    }));
+
+    let data = packet.serialize();
+
+    // Initialize the broadcast receiver socket in case it
+    // hasn't already been started so we can listen for
+    // multicast queries/announcements on all interfaces.
+    this._getBroadcastReceiverSocket();
+
+    this._getQuerySocket().then((querySocket) => {
+      DEBUG && debug('sending query on query socket ("' + name + '")');
+      querySocket.send(MDNS_MULTICAST_GROUP, MDNS_PORT, data, data.length);
+    });
+
+    // Automatically announce previously-discovered
+    // services that match and haven't expired yet.
+    setTimeout(() => {
+      DEBUG && debug('announcing previously discovered services ("' + name + '")');
+      let { serviceType } = _parseServiceDomainName(name);
+
+      this._clearExpiredDiscoveries();
+      this._discovered.forEach((discovery, key) => {
+        let serviceInfo = discovery.serviceInfo;
+        if (serviceInfo.serviceType !== serviceType) {
+          return;
+        }
+
+        let listeners = this._listeners.get(serviceInfo.serviceType) || [];
+        listeners.forEach((listener) => {
+          listener.onServiceFound(serviceInfo);
+        });
+      });
+    });
+  }
+
+  _clearExpiredDiscoveries() {
+    this._discovered.forEach((discovery, key) => {
+      if (discovery.expireTime < Date.now()) {
+        this._discovered.delete(key);
+        return;
+      }
+    });
+  }
+
+  _handleQueryPacket(packet, message) {
+    packet.getRecords(['QD']).forEach((record) => {
+      // Don't respond if the query's class code is not IN or ANY.
+      if (record.classCode !== DNS_CLASS_CODES.IN &&
+          record.classCode !== DNS_CLASS_CODES.ANY) {
+        return;
+      }
+
+      // Don't respond if the query's record type is not PTR or ANY.
+      if (record.recordType !== DNS_RECORD_TYPES.PTR &&
+          record.recordType !== DNS_RECORD_TYPES.ANY) {
+        return;
+      }
+
+      for (let [serviceKey, publishedService] of this._services) {
+        DEBUG && debug("_handleQueryPacket: " + packet.toJSON());
+        if (publishedService.ptrMatch(record.name)) {
+          this._respondToQuery(serviceKey, message);
+        }
+      }
+    });
+  }
+
+  _makeServicePacket(service, addresses) {
+    let packet = new DNSPacket();
+    packet.setFlag('QR', DNS_QUERY_RESPONSE_CODES.RESPONSE);
+    packet.setFlag('AA', DNS_AUTHORITATIVE_ANSWER_CODES.YES);
+
+    let host = service.host || _hostname;
+
+    // e.g.: foo-bar-service._http._tcp.local
+    let serviceDomainName = service.serviceName + '.' + service.serviceType + '.local';
+
+    // PTR Record
+    packet.addRecord('AN', new DNSResourceRecord({
+      name: service.serviceType + '.local', // e.g.: _http._tcp.local
+      recordType: DNS_RECORD_TYPES.PTR,
+      data: serviceDomainName
+    }));
+
+    // SRV Record
+    packet.addRecord('AR', new DNSResourceRecord({
+      name: serviceDomainName,
+      recordType: DNS_RECORD_TYPES.SRV,
+      classCode: DNS_CLASS_CODES.IN,
+      cacheFlush: true,
+      data: {
+        priority: 0,
+        weight: 0,
+        port: service.port,
+        target: host // e.g.: My-Android-Phone.local
+      }
+    }));
+
+    // A Records
+    for (let address of addresses) {
+        packet.addRecord('AR', new DNSResourceRecord({
+          name: host,
+          recordType: DNS_RECORD_TYPES.A,
+          data: address
+        }));
+    }
+
+    // TXT Record
+    packet.addRecord('AR', new DNSResourceRecord({
+      name: serviceDomainName,
+      recordType: DNS_RECORD_TYPES.TXT,
+      classCode: DNS_CLASS_CODES.IN,
+      cacheFlush: true,
+      data: service.serviceAttrs || {}
+    }));
+
+    return packet;
+  }
+
+  _handleResponsePacket(packet, message) {
+    let services = {};
+    let hosts = {};
+
+    let srvRecords = packet.getRecords(['AN', 'AR'], DNS_RECORD_TYPES.SRV);
+    let txtRecords = packet.getRecords(['AN', 'AR'], DNS_RECORD_TYPES.TXT);
+    let ptrRecords = packet.getRecords(['AN', 'AR'], DNS_RECORD_TYPES.PTR);
+    let aRecords = packet.getRecords(['AN', 'AR'], DNS_RECORD_TYPES.A);
+
+    srvRecords.forEach((record) => {
+      let data = record.data || {};
+
+      services[record.name] = {
+        host: data.target,
+        port: data.port,
+        ttl: record.ttl
+      };
+    });
+
+    txtRecords.forEach((record) => {
+      if (!services[record.name]) {
+        return;
+      }
+
+      services[record.name].attributes = record.data;
+    });
+
+    aRecords.forEach((record) => {
+      if (IsIpv4Address(record.data)) {
+        hosts[record.name] = record.data;
+      }
+    });
+
+    ptrRecords.forEach((record) => {
+      let name = record.data;
+      if (!services[name]) {
+        return;
+      }
+
+      let {host, port} = services[name];
+      if (!host || !port) {
+        return;
+      }
+
+      let { serviceName, serviceType, domainName } = _parseServiceDomainName(name);
+      if (!serviceName || !serviceType || !domainName) {
+        return;
+      }
+
+      let address = hosts[host];
+      if (!address) {
+        return;
+      }
+
+      let ttl = services[name].ttl || 0;
+      let serviceInfo = {
+        serviceName: serviceName,
+        serviceType: serviceType,
+        host: host,
+        address: address,
+        port: port,
+        domainName: domainName,
+        attributes: services[name].attributes || {}
+      };
+
+      this._onServiceFound(serviceInfo, ttl);
+    });
+  }
+
+  _onServiceFound(serviceInfo, ttl = 0) {
+    let expireTime = Date.now() + (ttl * 1000);
+    let key = serviceInfo.serviceName + '.' +
+              serviceInfo.serviceType + '.' +
+              serviceInfo.domainName + ' @' +
+              serviceInfo.address + ':' +
+              serviceInfo.port;
+
+    // If this service was already discovered, just update
+    // its expiration time and don't re-emit it.
+    if (this._discovered.has(key)) {
+      this._discovered.get(key).expireTime = expireTime;
+      return;
+    }
+
+    this._discovered.set(key, {
+      serviceInfo: serviceInfo,
+      expireTime: expireTime
+    });
+
+    let listeners = this._listeners.get(serviceInfo.serviceType) || [];
+    listeners.forEach((listener) => {
+      listener.onServiceFound(serviceInfo);
+    });
+
+    DEBUG && debug('_onServiceFound()' + serviceInfo.serviceName);
+  }
+
+  /**
+   * Gets a non-exclusive socket on 0.0.0.0:{random} to send
+   * multicast queries on all interfaces. This socket does
+   * not need to join a multicast group since it is still
+   * able to *send* multicast queries, but it does not need
+   * to *listen* for multicast queries/announcements since
+   * the `_broadcastReceiverSocket` is already handling them.
+   */
+  _getQuerySocket() {
+    return new Promise((resolve, reject) => {
+      if (!this._querySocket) {
+        this._querySocket = _openSocket('0.0.0.0', 0, {
+          onPacketReceived: this._onPacketReceived.bind(this),
+          onStopListening: this._onStopListening.bind(this)
+        });
+      }
+      resolve(this._querySocket);
+    });
+  }
+
+  /**
+   * Gets a non-exclusive socket on 0.0.0.0:5353 to listen
+   * for multicast queries/announcements on all interfaces.
+   * Since this socket needs to listen for multicast queries
+   * and announcements, this socket joins the multicast
+   * group on *all* interfaces (0.0.0.0).
+   */
+  _getBroadcastReceiverSocket() {
+    return new Promise((resolve, reject) => {
+      if (!this._broadcastReceiverSocket) {
+        this._broadcastReceiverSocket = _openSocket('0.0.0.0', MDNS_PORT, {
+          onPacketReceived: this._onPacketReceived.bind(this),
+          onStopListening: this._onStopListening.bind(this)
+        }, /* multicastInterface = */ '0.0.0.0');
+      }
+      resolve(this._broadcastReceiverSocket);
+    });
+  }
+
+  /**
+   * Gets a non-exclusive socket for each interface on
+   * {iface-ip}:5353 for sending query responses as
+   * well as for listening for unicast queries. These
+   * sockets do not need to join a multicast group
+   * since they are still able to *send* multicast
+   * query responses, but they do not need to *listen*
+   * for multicast queries since the `_querySocket` is
+   * already handling them.
+   */
+  _getSockets() {
+    return new Promise((resolve) => {
+      if (this._sockets.size > 0) {
+        resolve(this._sockets);
+        return;
+      }
+
+      Promise.all([getAddresses(), getHostname()]).then(() => {
+        _addresses.forEach((address) => {
+          let socket = _openSocket(address, MDNS_PORT, null);
+          this._sockets.set(address, socket);
+        });
+
+        resolve(this._sockets);
+      });
+    });
+  }
+
+  _checkCloseSockets() {
+    // Nothing to do if no sockets to close.
+    if (this._sockets.size == 0)
+      return;
+
+    // Don't close sockets if discovery listeners are still present.
+    if (this._listeners.size > 0)
+      return;
+
+    // Don't close sockets if advertised services are present.
+    // Since we need to listen for service queries and respond to them.
+    if (this._services.size > 0)
+      return;
+
+    this._closeSockets();
+  }
+
+  _closeSockets() {
+    this._sockets.forEach(socket => socket.close());
+    this._sockets.clear();
+  }
+
+  _onPacketReceived(socket, message) {
+    let packet = DNSPacket.parse(message.rawData);
+
+    switch (packet.getFlag('QR')) {
+      case DNS_QUERY_RESPONSE_CODES.QUERY:
+        this._handleQueryPacket(packet, message);
+        break;
+      case DNS_QUERY_RESPONSE_CODES.RESPONSE:
+        this._handleResponsePacket(packet, message);
+        break;
+      default:
+        break;
+    }
+  }
+
+  _onStopListening(socket, status) {
+    DEBUG && debug('_onStopListening() ' + status);
+  }
+
+  _addServiceListener(serviceType, listener) {
+    let listeners = this._listeners.get(serviceType);
+    if (!listeners) {
+      listeners = [];
+      this._listeners.set(serviceType, listeners);
+    }
+
+    if (!listeners.find(l => l === listener)) {
+      listeners.push(listener);
+    }
+  }
+
+  _removeServiceListener(serviceType, listener) {
+    let listeners = this._listeners.get(serviceType);
+    if (!listeners) {
+      return;
+    }
+
+    let index = listeners.findIndex(l => l === listener);
+    if (index >= 0) {
+      listeners.splice(index, 1);
+    }
+
+    if (listeners.length === 0) {
+      this._listeners.delete(serviceType);
+    }
+  }
+}
+
+let _addresses;
+
+/**
+ * @private
+ */
+function getAddresses() {
+  return new Promise((resolve, reject) => {
+    if (_addresses) {
+      resolve(_addresses);
+      return;
+    }
+
+    networkInfoService.listNetworkAddresses({
+      onListedNetworkAddresses(aAddressArray) {
+        _addresses = aAddressArray.filter((address) => {
+          return address.indexOf('%p2p') === -1 &&  // No WiFi Direct interfaces
+                 address.indexOf(':')    === -1 &&  // XXX: No IPv6 for now
+                 address != "127.0.0.1"             // No ipv4 loopback addresses.
+        });
+
+        DEBUG && debug('getAddresses(): ' + _addresses);
+        resolve(_addresses);
+      },
+
+      onListNetworkAddressesFailed() {
+        DEBUG && debug('getAddresses() FAILED!');
+        resolve([]);
+      }
+    });
+  });
+}
+
+let _hostname;
+
+/**
+ * @private
+ */
+function getHostname() {
+  return new Promise((resolve) => {
+    if (_hostname) {
+      resolve(_hostname);
+      return;
+    }
+
+    networkInfoService.getHostname({
+      onGotHostname(aHostname) {
+        _hostname = aHostname.replace(/\s/g, '-') + '.local';
+
+        DEBUG && debug('getHostname(): ' + _hostname);
+        resolve(_hostname);
+      },
+
+      onGetHostnameFailed() {
+        DEBUG && debug('getHostname() FAILED');
+        resolve('localhost');
+      }
+    });
+  });
+}
+
+/**
+ * Parse fully qualified domain name to service name, instance name,
+ * and domain name. See https://tools.ietf.org/html/rfc6763#section-7.
+ *
+ * Example: 'foo-bar-service._http._tcp.local' -> {
+ *   serviceName: 'foo-bar-service',
+ *   serviceType: '_http._tcp',
+ *   domainName: 'local'
+ * }
+ *
+ * @private
+ */
+function _parseServiceDomainName(serviceDomainName) {
+  let parts = serviceDomainName.split('.');
+  let index = Math.max(parts.lastIndexOf('_tcp'), parts.lastIndexOf('_udp'));
+
+  return {
+    serviceName: parts.splice(0, index - 1).join('.'),
+    serviceType: parts.splice(0, 2).join('.'),
+    domainName: parts.join('.')
+  };
+}
+
+/**
+ * @private
+ */
+function _propertyBagToObject(propBag) {
+  let result = {};
+  if (propBag.QueryInterface) {
+    propBag.QueryInterface(Ci.nsIPropertyBag2);
+    let propEnum = propBag.enumerator;
+    while (propEnum.hasMoreElements()) {
+      let prop = propEnum.getNext().QueryInterface(Ci.nsIProperty);
+      result[prop.name] = prop.value.toString();
+    }
+  } else {
+    for (let name in propBag) {
+      result[name] = propBag[name].toString();
+    }
+  }
+  return result;
+}
+
+/**
+ * @private
+ */
+function _openSocket(addr, port, handler, multicastInterface) {
+  let socket = Cc['@mozilla.org/network/udp-socket;1'].createInstance(Ci.nsIUDPSocket);
+  socket.init2(addr, port, Services.scriptSecurityManager.getSystemPrincipal(), true);
+
+  if (handler) {
+    socket.asyncListen({
+      onPacketReceived: handler.onPacketReceived,
+      onStopListening: handler.onStopListening
+    });
+  }
+
+  if (multicastInterface) {
+    socket.joinMulticast(MDNS_MULTICAST_GROUP, multicastInterface);
+  }
+
+  return socket;
+}