The Tor Browser: mobile/android/modules/SimpleServiceDiscovery.jsm@fc2d59ddac77 (annotated)

mobile/android/modules/SimpleServiceDiscovery.jsm@fc2d59ddac77 (annotated)

mobile/android/modules/SimpleServiceDiscovery.jsm

Wed, 31 Dec 2014 07:22:50 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Wed, 31 Dec 2014 07:22:50 +0100
branch: TOR_BUG_3246
changeset 4: fc2d59ddac77
permissions: -rw-r--r--

Correct previous dual key logic pending first delivery installment.

 // -*- Mode: js2; tab-width: 2; indent-tabs-mode: nil; js2-basic-offset: 2; js2-skip-preprocessor-directives: t; -*-
 /* 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/. */
 "use strict";
 this.EXPORTED_SYMBOLS = ["SimpleServiceDiscovery"];
 const { classes: Cc, interfaces: Ci, utils: Cu } = Components;
 Cu.import("resource://gre/modules/Services.jsm");
 Cu.import("resource://gre/modules/XPCOMUtils.jsm");
 function log(msg) {
   Services.console.logStringMessage("[SSDP] " + msg);
 }
 XPCOMUtils.defineLazyGetter(this, "converter", function () {
   let conv = Cc["@mozilla.org/intl/scriptableunicodeconverter"].createInstance(Ci.nsIScriptableUnicodeConverter);
   conv.charset = "utf8";
   return conv;
 });
 // Spec information:
 // https://tools.ietf.org/html/draft-cai-ssdp-v1-03
 // http://www.dial-multiscreen.org/dial-protocol-specification
 const SSDP_PORT = 1900;
 const SSDP_ADDRESS = "239.255.255.250";
 const SSDP_DISCOVER_PACKET =
   "M-SEARCH * HTTP/1.1\r\n" +
   "HOST: " + SSDP_ADDRESS + ":" + SSDP_PORT + "\r\n" +
   "MAN: \"ssdp:discover\"\r\n" +
   "MX: 2\r\n" +
   "ST: %SEARCH_TARGET%\r\n\r\n";
 const SSDP_DISCOVER_TIMEOUT = 10000;
 /*
  * SimpleServiceDiscovery manages any discovered SSDP services. It uses a UDP
  * broadcast to locate available services on the local network.
  */
 var SimpleServiceDiscovery = {
   _targets: new Map(),
   _services: new Map(),
   _searchSocket: null,
   _searchInterval: 0,
   _searchTimestamp: 0,
   _searchTimeout: Cc["@mozilla.org/timer;1"].createInstance(Ci.nsITimer),
   _searchRepeat: Cc["@mozilla.org/timer;1"].createInstance(Ci.nsITimer),
   _forceTrailingSlash: function(aURL) {
     // Some devices add the trailing '/' and some don't. Let's make sure
     // it's there for consistency.
     if (!aURL.endsWith("/")) {
       aURL += "/";
     }
     return aURL;
   },
   // nsIUDPSocketListener implementation
   onPacketReceived: function(aSocket, aMessage) {
     // Listen for responses from specific targets. There could be more than one
     // available.
     let response = aMessage.data.split("\n");
     let location;
     let target;
     let valid = false;
     response.some(function(row) {
       let header = row.toUpperCase();
       if (header.startsWith("LOCATION")) {
         location = row.substr(10).trim();
       } else if (header.startsWith("ST")) {
         target = row.substr(4).trim();
         if (this._targets.has(target)) {
           valid = true;
         }
       }
       if (location && valid) {
         location = this._forceTrailingSlash(location);
         // When we find a valid response, package up the service information
         // and pass it on.
         let service = {
           location: location,
           target: target
         };
         try {
           this._processService(service);
         } catch (e) {}
         return true;
       }
       return false;
     }.bind(this));
   },
   onStopListening: function(aSocket, aStatus) {
     // This is fired when the socket is closed expectedly or unexpectedly.
     // nsITimer.cancel() is a no-op if the timer is not active.
     this._searchTimeout.cancel();
     this._searchSocket = null;
   },
   // Start a search. Make it continuous by passing an interval (in milliseconds).
   // This will stop a current search loop because the timer resets itself.
   search: function search(aInterval) {
     if (aInterval > 0) {
       this._searchInterval = aInterval || 0;
       this._searchRepeat.initWithCallback(this._search.bind(this), this._searchInterval, Ci.nsITimer.TYPE_REPEATING_SLACK);
     }
     this._search();
   },
   // Stop the current continuous search
   stopSearch: function stopSearch() {
     this._searchRepeat.cancel();
   },
   _usingLAN: function() {
     let network = Cc["@mozilla.org/network/network-link-service;1"].getService(Ci.nsINetworkLinkService);
     return (network.linkType == Ci.nsINetworkLinkService.LINK_TYPE_WIFI || network.linkType == Ci.nsINetworkLinkService.LINK_TYPE_ETHERNET);
   },
   _search: function _search() {
     // If a search is already active, shut it down.
     this._searchShutdown();
     // We only search if on local network
     if (!this._usingLAN()) {
       return;
     }
     // Update the timestamp so we can use it to clean out stale services the
     // next time we search.
     this._searchTimestamp = Date.now();
     // Look for any fixed IP targets. Some routers might be configured to block
     // UDP broadcasts, so this is a way to skip discovery.
     this._searchFixedTargets();
     // Perform a UDP broadcast to search for SSDP devices
     let socket = Cc["@mozilla.org/network/udp-socket;1"].createInstance(Ci.nsIUDPSocket);
     try {
       socket.init(SSDP_PORT, false);
       socket.asyncListen(this);
     } catch (e) {
       // We were unable to create the broadcast socket. Just return, but don't
       // kill the interval timer. This might work next time.
       log("failed to start socket: " + e);
       return;
     }
     this._searchSocket = socket;
     this._searchTimeout.initWithCallback(this._searchShutdown.bind(this), SSDP_DISCOVER_TIMEOUT, Ci.nsITimer.TYPE_ONE_SHOT);
     let data = SSDP_DISCOVER_PACKET;
     for (let [key, target] of this._targets) {
       let msgData = data.replace("%SEARCH_TARGET%", target.target);
       try {
         let msgRaw = converter.convertToByteArray(msgData);
         socket.send(SSDP_ADDRESS, SSDP_PORT, msgRaw, msgRaw.length);
       } catch (e) {
         log("failed to convert to byte array: " + e);
       }
     }
   },
   _searchFixedTargets: function _searchFixedTargets() {
     let fixedTargets = null;
     try {
       fixedTargets = Services.prefs.getCharPref("browser.casting.fixedTargets");
     } catch (e) {}
     if (!fixedTargets) {
       return;
     }
     fixedTargets = JSON.parse(fixedTargets);
     for (let fixedTarget of fixedTargets) {
       // Verify we have the right data
       if (!"location" in fixedTarget || !"target" in fixedTarget) {
         continue;
       }
       fixedTarget.location = this._forceTrailingSlash(fixedTarget.location);
       let service = {
         location: fixedTarget.location,
         target: fixedTarget.target
       };
       // We don't assume the fixed target is ready. We still need to ping it.
       try {
         this._processService(service);
       } catch (e) {}
     }
   },
   // Called when the search timeout is hit. We use it to cleanup the socket and
   // perform some post-processing on the services list.
   _searchShutdown: function _searchShutdown() {
     if (this._searchSocket) {
       // This will call onStopListening.
       this._searchSocket.close();
       // Clean out any stale services
       for (let [key, service] of this._services) {
         if (service.lastPing != this._searchTimestamp) {
           Services.obs.notifyObservers(null, "ssdp-service-lost", service.location);
           this._services.delete(service.location);
         }
       }
     }
   },
   registerTarget: function registerTarget(aTarget, aAppFactory) {
     // Only add if we don't already know about this target
     if (!this._targets.has(aTarget)) {
       this._targets.set(aTarget, { target: aTarget, factory: aAppFactory });
     }
   },
   findAppForService: function findAppForService(aService, aApp) {
     if (!aService || !aService.target) {
       return null;
     }
     // Find the registration for the target
     if (this._targets.has(aService.target)) {
       return this._targets.get(aService.target).factory(aService, aApp);
     }
     return null;
   },
   findServiceForLocation: function findServiceForLocation(aLocation) {
     if (this._services.has(aLocation)) {
       return this._services.get(aLocation);
     }
     return null;
   },
   // Returns an array copy of the active services
   get services() {
     let array = [];
     for (let [key, service] of this._services) {
       array.push(service);
     }
     return array;
   },
   _processService: function _processService(aService) {
     // Use the REST api to request more information about this service
     let xhr = Cc["@mozilla.org/xmlextras/xmlhttprequest;1"].createInstance(Ci.nsIXMLHttpRequest);
     xhr.open("GET", aService.location, true);
     xhr.channel.loadFlags |= Ci.nsIRequest.INHIBIT_CACHING;
     xhr.overrideMimeType("text/xml");
     xhr.addEventListener("load", (function() {
       if (xhr.status == 200) {
         let doc = xhr.responseXML;
         aService.appsURL = xhr.getResponseHeader("Application-URL");
         if (aService.appsURL && !aService.appsURL.endsWith("/"))
           aService.appsURL += "/";
         aService.friendlyName = doc.querySelector("friendlyName").textContent;
         aService.uuid = doc.querySelector("UDN").textContent;
         aService.manufacturer = doc.querySelector("manufacturer").textContent;
         aService.modelName = doc.querySelector("modelName").textContent;
         // Only add and notify if we don't already know about this service
         if (!this._services.has(aService.location)) {
           this._services.set(aService.location, aService);
           Services.obs.notifyObservers(null, "ssdp-service-found", aService.location);
         }
         // Make sure we remember this service is not stale
         this._services.get(aService.location).lastPing = this._searchTimestamp;
       }
     }).bind(this), false);
     xhr.send(null);
   }
 }

The Tor Browser / annotate

mobile/android/modules/SimpleServiceDiscovery.jsm@fc2d59ddac77 (annotated)

mobile/android/modules/SimpleServiceDiscovery.jsm