The Tor Browser: dom/system/gonk/Nfc.js@b8a032363ba2 (annotated)

dom/system/gonk/Nfc.js@b8a032363ba2 (annotated)

dom/system/gonk/Nfc.js

Thu, 22 Jan 2015 13:21:57 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 22 Jan 2015 13:21:57 +0100
branch: TOR_BUG_9701
changeset 15: b8a032363ba2
permissions: -rw-r--r--

Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6

 /* Copyright 2012 Mozilla Foundation and Mozilla contributors
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *     http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
 /* Copyright © 2013, Deutsche Telekom, Inc. */
 "use strict";
 const {classes: Cc, interfaces: Ci, utils: Cu, results: Cr} = Components;
 Cu.import("resource://gre/modules/XPCOMUtils.jsm");
 Cu.import("resource://gre/modules/Services.jsm");
 let NFC = {};
 Cu.import("resource://gre/modules/nfc_consts.js", NFC);
 Cu.import("resource://gre/modules/systemlibs.js");
 const NFC_ENABLED = libcutils.property_get("ro.moz.nfc.enabled", "false") === "true";
 // set to true in nfc_consts.js to see debug messages
 let DEBUG = NFC.DEBUG_NFC;
 let debug;
 if (DEBUG) {
   debug = function (s) {
     dump("-*- Nfc: " + s + "\n");
   };
 } else {
   debug = function (s) {};
 }
 const NFC_CONTRACTID = "@mozilla.org/nfc;1";
 const NFC_CID =
   Components.ID("{2ff24790-5e74-11e1-b86c-0800200c9a66}");
 const NFC_IPC_MSG_NAMES = [
   "NFC:SetSessionToken"
 ];
 const NFC_IPC_READ_PERM_MSG_NAMES = [
   "NFC:ReadNDEF",
   "NFC:GetDetailsNDEF",
   "NFC:Connect",
   "NFC:Close",
 ];
 const NFC_IPC_WRITE_PERM_MSG_NAMES = [
   "NFC:WriteNDEF",
   "NFC:MakeReadOnlyNDEF",
   "NFC:SendFile",
   "NFC:RegisterPeerTarget",
   "NFC:UnregisterPeerTarget"
 ];
 const NFC_IPC_MANAGER_PERM_MSG_NAMES = [
   "NFC:CheckP2PRegistration",
   "NFC:NotifyUserAcceptedP2P",
   "NFC:NotifySendFileStatus",
   "NFC:StartPoll",
   "NFC:StopPoll",
   "NFC:PowerOff"
 ];
 XPCOMUtils.defineLazyServiceGetter(this, "ppmm",
                                    "@mozilla.org/parentprocessmessagemanager;1",
                                    "nsIMessageBroadcaster");
 XPCOMUtils.defineLazyServiceGetter(this, "gSystemMessenger",
                                    "@mozilla.org/system-message-internal;1",
                                    "nsISystemMessagesInternal");
 XPCOMUtils.defineLazyServiceGetter(this, "gSystemWorkerManager",
                                    "@mozilla.org/telephony/system-worker-manager;1",
                                    "nsISystemWorkerManager");
 XPCOMUtils.defineLazyServiceGetter(this, "UUIDGenerator",
                                     "@mozilla.org/uuid-generator;1",
                                     "nsIUUIDGenerator");
 XPCOMUtils.defineLazyGetter(this, "gMessageManager", function () {
   return {
     QueryInterface: XPCOMUtils.generateQI([Ci.nsIMessageListener,
                                            Ci.nsIObserver]),
     nfc: null,
     // Manage message targets in terms of sessionToken. Only the authorized and
     // registered contents can receive related messages.
     targetsBySessionTokens: {},
     sessionTokens: [],
     // Manage registered Peer Targets
     peerTargetsMap: {},
     currentPeerAppId: null,
     init: function init(nfc) {
       this.nfc = nfc;
       Services.obs.addObserver(this, NFC.TOPIC_XPCOM_SHUTDOWN, false);
       this._registerMessageListeners();
     },
     _shutdown: function _shutdown() {
       this.nfc = null;
       Services.obs.removeObserver(this, NFC.TOPIC_XPCOM_SHUTDOWN);
       this._unregisterMessageListeners();
     },
     _registerMessageListeners: function _registerMessageListeners() {
       ppmm.addMessageListener("child-process-shutdown", this);
       for (let msgname of NFC_IPC_MSG_NAMES) {
         ppmm.addMessageListener(msgname, this);
       }
       for (let msgname of NFC_IPC_READ_PERM_MSG_NAMES) {
         ppmm.addMessageListener(msgname, this);
       }
       for (let msgname of NFC_IPC_WRITE_PERM_MSG_NAMES) {
         ppmm.addMessageListener(msgname, this);
       }
       for (let msgname of NFC_IPC_MANAGER_PERM_MSG_NAMES) {
         ppmm.addMessageListener(msgname, this);
       }
     },
     _unregisterMessageListeners: function _unregisterMessageListeners() {
       ppmm.removeMessageListener("child-process-shutdown", this);
       for (let msgname of NFC_IPC_MSG_NAMES) {
         ppmm.removeMessageListener(msgname, this);
       }
       for (let msgname of NFC_IPC_READ_PERM_MSG_NAMES) {
         ppmm.removeMessageListener(msgname, this);
       }
       for (let msgname of NFC_IPC_WRITE_PERM_MSG_NAMES) {
         ppmm.removeMessageListener(msgname, this);
       }
       for (let msgname of NFC_IPC_MANAGER_PERM_MSG_NAMES) {
         ppmm.removeMessageListener(msgname, this);
       }
       ppmm = null;
     },
     _registerMessageTarget: function _registerMessageTarget(sessionToken, target) {
       let targets = this.targetsBySessionTokens[sessionToken];
       if (!targets) {
         targets = this.targetsBySessionTokens[sessionToken] = [];
         let list = this.sessionTokens;
         if (list.indexOf(sessionToken) == -1) {
           list.push(sessionToken);
         }
       }
       if (targets.indexOf(target) != -1) {
         debug("Already registered this target!");
         return;
       }
       targets.push(target);
       debug("Registered :" + sessionToken + " target: " + target);
     },
     _unregisterMessageTarget: function _unregisterMessageTarget(sessionToken, target) {
       if (sessionToken == null) {
         // Unregister the target for every sessionToken when no sessionToken is specified.
         for (let session of this.sessionTokens) {
           this._unregisterMessageTarget(session, target);
         }
         return;
       }
       // Unregister the target for a specified sessionToken.
       let targets = this.targetsBySessionTokens[sessionToken];
       if (!targets) {
         return;
       }
       if (target == null) {
         debug("Unregistered all targets for the " + sessionToken + " targets: " + targets);
         targets = [];
         let list = this.sessionTokens;
         if (sessionToken !== null) {
           let index = list.indexOf(sessionToken);
           if (index > -1) {
             list.splice(index, 1);
           }
         }
         return;
       }
       let index = targets.indexOf(target);
       if (index != -1) {
         targets.splice(index, 1);
       }
     },
     _sendTargetMessage: function _sendTargetMessage(sessionToken, message, options) {
       let targets = this.targetsBySessionTokens[sessionToken];
       if (!targets) {
         return;
       }
       for (let target of targets) {
         target.sendAsyncMessage(message, options);
       }
     },
     registerPeerTarget: function registerPeerTarget(msg) {
       let appInfo = msg.json;
       // Sanity check on PeerEvent
       if (!this.isValidPeerEvent(appInfo.event)) {
         return;
       }
       let targets = this.peerTargetsMap;
       let targetInfo = targets[appInfo.appId];
       // If the application Id is already registered
       if (targetInfo) {
         // If the event is not registered
         if (targetInfo.event !== appInfo.event) {
           // Update the event field ONLY
           targetInfo.event |= appInfo.event;
         }
         // Otherwise event is already registered, return!
         return;
       }
       // Target not registered yet! Add to the target map
       // Registered targetInfo target consists of 2 fields (values)
       // target : Target to notify the right content for peer notifications
       // event  : NFC_PEER_EVENT_READY (0x01) Or NFC_PEER_EVENT_LOST (0x02)
       let newTargetInfo = { target : msg.target,
                             event  : appInfo.event };
       targets[appInfo.appId] = newTargetInfo;
     },
     unregisterPeerTarget: function unregisterPeerTarget(msg) {
       let appInfo = msg.json;
       // Sanity check on PeerEvent
       if (!this.isValidPeerEvent(appInfo.event)) {
         return;
       }
       let targets = this.peerTargetsMap;
       let targetInfo = targets[appInfo.appId];
       if (targetInfo) {
         // Application Id registered and the event exactly matches.
         if (targetInfo.event === appInfo.event) {
           // Remove the target from the list of registered targets
           delete targets[appInfo.appId]
         }
         else {
           // Otherwise, update the event field ONLY, by removing the event flag
           targetInfo.event &= ~appInfo.event;
         }
       }
     },
     removePeerTarget: function removePeerTarget(target) {
       let targets = this.peerTargetsMap;
       Object.keys(targets).forEach((appId) => {
         let targetInfo = targets[appId];
         if (targetInfo && targetInfo.target === target) {
           // Remove the target from the list of registered targets
           delete targets[appId];
         }
       });
     },
     isRegisteredP2PTarget: function isRegisteredP2PTarget(appId, event) {
       let targetInfo = this.peerTargetsMap[appId];
       // Check if it is a registered target for the 'event'
       return ((targetInfo != null) && (targetInfo.event & event !== 0));
     },
     notifyPeerEvent: function notifyPeerEvent(appId, event) {
       let targetInfo = this.peerTargetsMap[appId];
       // Check if the application id is a registeredP2PTarget
       if (this.isRegisteredP2PTarget(appId, event)) {
         targetInfo.target.sendAsyncMessage("NFC:PeerEvent", {
           event: event,
           sessionToken: this.nfc.sessionTokenMap[this.nfc._currentSessionId]
         });
         return;
       }
       debug("Application ID : " + appId + " is not a registered target" +
                              "for the event " + event + " notification");
     },
     isValidPeerEvent: function isValidPeerEvent(event) {
       // Valid values : 0x01, 0x02 Or 0x03
       return ((event === NFC.NFC_PEER_EVENT_READY) ||
               (event === NFC.NFC_PEER_EVENT_LOST)  ||
               (event === (NFC.NFC_PEER_EVENT_READY | NFC.NFC_PEER_EVENT_LOST)));
     },
     /**
      * nsIMessageListener interface methods.
      */
     receiveMessage: function receiveMessage(msg) {
       debug("Received '" + msg.name + "' message from content process");
       if (msg.name == "child-process-shutdown") {
         // By the time we receive child-process-shutdown, the child process has
         // already forgotten its permissions so we need to unregister the target
         // for every permission.
         this._unregisterMessageTarget(null, msg.target);
         this.removePeerTarget(msg.target);
         return null;
       }
       if (NFC_IPC_MSG_NAMES.indexOf(msg.name) != -1) {
         // Do nothing.
       } else if (NFC_IPC_READ_PERM_MSG_NAMES.indexOf(msg.name) != -1) {
         if (!msg.target.assertPermission("nfc-read")) {
           debug("Nfc message " + msg.name +
                 " from a content process with no 'nfc-read' privileges.");
           return null;
         }
       } else if (NFC_IPC_WRITE_PERM_MSG_NAMES.indexOf(msg.name) != -1) {
         if (!msg.target.assertPermission("nfc-write")) {
           debug("Nfc Peer message  " + msg.name +
                 " from a content process with no 'nfc-write' privileges.");
           return null;
         }
       } else if (NFC_IPC_MANAGER_PERM_MSG_NAMES.indexOf(msg.name) != -1) {
         if (!msg.target.assertPermission("nfc-manager")) {
           debug("NFC message " + message.name +
                 " from a content process with no 'nfc-manager' privileges.");
           return null;
         }
       } else {
         debug("Ignoring unknown message type: " + msg.name);
         return null;
       }
       switch (msg.name) {
         case "NFC:SetSessionToken":
           this._registerMessageTarget(this.nfc.sessionTokenMap[this.nfc._currentSessionId], msg.target);
           debug("Registering target for this SessionToken : " +
                 this.nfc.sessionTokenMap[this.nfc._currentSessionId]);
           return null;
         case "NFC:RegisterPeerTarget":
           this.registerPeerTarget(msg);
           return null;
         case "NFC:UnregisterPeerTarget":
           this.unregisterPeerTarget(msg);
           return null;
         case "NFC:CheckP2PRegistration":
           // Check if the application id is a valid registered target.
           // (It should have registered for NFC_PEER_EVENT_READY).
           let isRegistered = this.isRegisteredP2PTarget(msg.json.appId,
                                                         NFC.NFC_PEER_EVENT_READY);
           // Remember the current AppId if registered.
           this.currentPeerAppId = (isRegistered) ? msg.json.appId : null;
           let status = (isRegistered) ? NFC.GECKO_NFC_ERROR_SUCCESS :
                                         NFC.GECKO_NFC_ERROR_GENERIC_FAILURE;
           // Notify the content process immediately of the status
           msg.target.sendAsyncMessage(msg.name + "Response", {
             status: status,
             requestId: msg.json.requestId
           });
           return null;
         case "NFC:NotifyUserAcceptedP2P":
           // Notify the 'NFC_PEER_EVENT_READY' since user has acknowledged
           this.notifyPeerEvent(msg.json.appId, NFC.NFC_PEER_EVENT_READY);
           return null;
         case "NFC:NotifySendFileStatus":
           // Upon receiving the status of sendFile operation, send the response
           // to appropriate content process.
           this.sendNfcResponseMessage(msg.name + "Response", msg.json);
           return null;
         default:
           return this.nfc.receiveMessage(msg);
       }
     },
     /**
      * nsIObserver interface methods.
      */
     observe: function observe(subject, topic, data) {
       switch (topic) {
         case NFC.TOPIC_XPCOM_SHUTDOWN:
           this._shutdown();
           break;
       }
     },
     sendNfcResponseMessage: function sendNfcResponseMessage(message, data) {
       this._sendTargetMessage(this.nfc.sessionTokenMap[this.nfc._currentSessionId], message, data);
     },
   };
 });
 function Nfc() {
   debug("Starting Worker");
   this.worker = new ChromeWorker("resource://gre/modules/nfc_worker.js");
   this.worker.onerror = this.onerror.bind(this);
   this.worker.onmessage = this.onmessage.bind(this);
   gMessageManager.init(this);
   // Maps sessionId (that are generated from nfcd) with a unique guid : 'SessionToken'
   this.sessionTokenMap = {};
   this.targetsByRequestId = {};
   gSystemWorkerManager.registerNfcWorker(this.worker);
 }
 Nfc.prototype = {
   classID:   NFC_CID,
   classInfo: XPCOMUtils.generateCI({classID: NFC_CID,
                                     classDescription: "Nfc",
                                     interfaces: [Ci.nsIWorkerHolder]}),
   QueryInterface: XPCOMUtils.generateQI([Ci.nsIWorkerHolder]),
   _currentSessionId: null,
   powerLevel: NFC.NFC_POWER_LEVEL_UNKNOWN,
   onerror: function onerror(event) {
     debug("Got an error: " + event.filename + ":" +
           event.lineno + ": " + event.message + "\n");
     event.preventDefault();
   },
   /**
    * Send arbitrary message to worker.
    *
    * @param nfcMessageType
    *        A text message type.
    * @param message [optional]
    *        An optional message object to send.
    */
   sendToWorker: function sendToWorker(nfcMessageType, message) {
     message = message || {};
     message.type = nfcMessageType;
     this.worker.postMessage(message);
   },
   /**
    * Send Error response to content.
    *
    * @param message
    *        An nsIMessageListener's message parameter.
    */
   sendNfcErrorResponse: function sendNfcErrorResponse(message) {
     if (!message.target) {
       return;
     }
     let nfcMsgType = message.name + "Response";
     message.target.sendAsyncMessage(nfcMsgType, {
       sessionId: message.json.sessionToken,
       requestId: message.json.requestId,
       status: NFC.GECKO_NFC_ERROR_GENERIC_FAILURE
     });
   },
   /**
    * Process the incoming message from the NFC worker
    */
   onmessage: function onmessage(event) {
     let message = event.data;
     debug("Received message from NFC worker: " + JSON.stringify(message));
     switch (message.type) {
       case "techDiscovered":
         this._currentSessionId = message.sessionId;
         // Check if the session token already exists. If exists, continue to use the same one.
         // If not, generate a new token.
         if (!this.sessionTokenMap[this._currentSessionId]) {
           this.sessionTokenMap[this._currentSessionId] = UUIDGenerator.generateUUID().toString();
         }
         // Update the upper layers with a session token (alias)
         message.sessionToken = this.sessionTokenMap[this._currentSessionId];
         // Do not expose the actual session to the content
         delete message.sessionId;
         gSystemMessenger.broadcastMessage("nfc-manager-tech-discovered", message);
         break;
       case "techLost":
         gMessageManager._unregisterMessageTarget(this.sessionTokenMap[this._currentSessionId], null);
         // Update the upper layers with a session token (alias)
         message.sessionToken = this.sessionTokenMap[this._currentSessionId];
         // Do not expose the actual session to the content
         delete message.sessionId;
         gSystemMessenger.broadcastMessage("nfc-manager-tech-lost", message);
         // Notify 'PeerLost' to appropriate registered target, if any
         gMessageManager.notifyPeerEvent(this.currentPeerAppId, NFC.NFC_PEER_EVENT_LOST);
         delete this.sessionTokenMap[this._currentSessionId];
         this._currentSessionId = null;
         this.currentPeerAppId = null;
         break;
      case "ConfigResponse":
         let target = this.targetsByRequestId[message.requestId];
         if (!target) {
           debug("No target for requestId: " + message.requestId);
           return;
         }
         delete this.targetsByRequestId[message.requestId];
         if (message.status == NFC.GECKO_NFC_ERROR_SUCCESS) {
           this.powerLevel = message.powerLevel;
         }
         target.sendAsyncMessage("NFC:ConfigResponse", message);
         break;
       case "ConnectResponse": // Fall through.
       case "CloseResponse":
       case "GetDetailsNDEFResponse":
       case "ReadNDEFResponse":
       case "MakeReadOnlyNDEFResponse":
       case "WriteNDEFResponse":
         message.sessionToken = this.sessionTokenMap[this._currentSessionId];
         // Do not expose the actual session to the content
         delete message.sessionId;
         gMessageManager.sendNfcResponseMessage("NFC:" + message.type, message);
         break;
       default:
         throw new Error("Don't know about this message type: " + message.type);
     }
   },
   // nsINfcWorker
   worker: null,
   sessionTokenMap: null,
   targetsByRequestId: null,
   /**
    * Process a message from the content process.
    */
   receiveMessage: function receiveMessage(message) {
     debug("Received '" + JSON.stringify(message) + "' message from content process");
     // Handle messages without sessionToken.
     if (message.name == "NFC:StartPoll") {
       this.targetsByRequestId[message.json.requestId] = message.target;
       this.setConfig({powerLevel: NFC.NFC_POWER_LEVEL_ENABLED,
                       requestId: message.json.requestId});
       return null;
     } else if (message.name == "NFC:StopPoll") {
       this.targetsByRequestId[message.json.requestId] = message.target;
       this.setConfig({powerLevel: NFC.NFC_POWER_LEVEL_LOW,
                       requestId: message.json.requestId});
       return null;
     } else if (message.name == "NFC:PowerOff") {
       this.targetsByRequestId[message.json.requestId] = message.target;
       this.setConfig({powerLevel: NFC.NFC_POWER_LEVEL_DISABLED,
                       requestId: message.json.requestId});
       return null;
     }
     if (this.powerLevel != NFC.NFC_POWER_LEVEL_ENABLED) {
       debug("NFC is not enabled. current powerLevel:" + this.powerLevel);
       this.sendNfcErrorResponse(message);
       return null;
     }
     // Sanity check on sessionId
     if (message.json.sessionToken !== this.sessionTokenMap[this._currentSessionId]) {
       debug("Invalid Session Token: " + message.json.sessionToken +
             " Expected Session Token: " + this.sessionTokenMap[this._currentSessionId]);
       this.sendNfcErrorResponse(message);
       return null;
     }
     // Update the current sessionId before sending to the worker
     message.json.sessionId = this._currentSessionId;
     switch (message.name) {
       case "NFC:GetDetailsNDEF":
         this.sendToWorker("getDetailsNDEF", message.json);
         break;
       case "NFC:ReadNDEF":
         this.sendToWorker("readNDEF", message.json);
         break;
       case "NFC:WriteNDEF":
         this.sendToWorker("writeNDEF", message.json);
         break;
       case "NFC:MakeReadOnlyNDEF":
         this.sendToWorker("makeReadOnlyNDEF", message.json);
         break;
       case "NFC:Connect":
         this.sendToWorker("connect", message.json);
         break;
       case "NFC:Close":
         this.sendToWorker("close", message.json);
         break;
       case "NFC:SendFile":
         // Chrome process is the arbitrator / mediator between
         // system app (content process) that issued nfc 'sendFile' operation
         // and system app that handles the system message :
         // 'nfc-manager-send-file'. System app subsequently handover's
         // the data to alternate carrier's (BT / WiFi) 'sendFile' interface.
         // Notify system app to initiate BT send file operation
         gSystemMessenger.broadcastMessage("nfc-manager-send-file",
                                            message.json);
         break;
       default:
         debug("UnSupported : Message Name " + message.name);
         return null;
     }
     return null;
   },
   setConfig: function setConfig(prop) {
     this.sendToWorker("config", prop);
   }
 };
 if (NFC_ENABLED) {
   this.NSGetFactory = XPCOMUtils.generateNSGetFactory([Nfc]);
 }