michael@0: /* -*- Mode: Java; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
michael@0:  * You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: 'use strict';
michael@0: 
michael@0: const { classes: Cc, interfaces: Ci, results: Cr, utils: Cu } = Components;
michael@0: 
michael@0: Cu.import('resource://gre/modules/XPCOMUtils.jsm');
michael@0: Cu.import('resource://gre/modules/Services.jsm');
michael@0: 
michael@0: const DEBUG = false; // set to true to show debug messages
michael@0: 
michael@0: const kCAPTIVEPORTALDETECTOR_CONTRACTID = '@mozilla.org/toolkit/captive-detector;1';
michael@0: const kCAPTIVEPORTALDETECTOR_CID        = Components.ID('{d9cd00ba-aa4d-47b1-8792-b1fe0cd35060}');
michael@0: 
michael@0: const kOpenCaptivePortalLoginEvent = 'captive-portal-login';
michael@0: const kAbortCaptivePortalLoginEvent = 'captive-portal-login-abort';
michael@0: 
michael@0: function URLFetcher(url, timeout) {
michael@0:   let self = this;
michael@0:   let xhr = Cc['@mozilla.org/xmlextras/xmlhttprequest;1']
michael@0:               .createInstance(Ci.nsIXMLHttpRequest);
michael@0:   xhr.open('GET', url, true);
michael@0:   // Prevent the request from reading from the cache.
michael@0:   xhr.channel.loadFlags |= Ci.nsIRequest.LOAD_BYPASS_CACHE;
michael@0:   // Prevent the request from writing to the cache.
michael@0:   xhr.channel.loadFlags |= Ci.nsIRequest.INHIBIT_CACHING;
michael@0:   // Prevent privacy leaks
michael@0:   xhr.channel.loadFlags |= Ci.nsIRequest.LOAD_ANONYMOUS;
michael@0:   // The Cache-Control header is only interpreted by proxies and the
michael@0:   // final destination. It does not help if a resource is already
michael@0:   // cached locally.
michael@0:   xhr.setRequestHeader("Cache-Control", "no-cache");
michael@0:   // HTTP/1.0 servers might not implement Cache-Control and
michael@0:   // might only implement Pragma: no-cache
michael@0:   xhr.setRequestHeader("Pragma", "no-cache");
michael@0: 
michael@0:   xhr.timeout = timeout;
michael@0:   xhr.ontimeout = function () { self.ontimeout(); };
michael@0:   xhr.onerror = function () { self.onerror(); };
michael@0:   xhr.onreadystatechange = function(oEvent) {
michael@0:     if (xhr.readyState === 4) {
michael@0:       if (self._isAborted) {
michael@0:         return;
michael@0:       }
michael@0:       if (xhr.status === 200) {
michael@0:         self.onsuccess(xhr.responseText);
michael@0:       } else if (xhr.status) {
michael@0:         self.onredirectorerror(xhr.status);
michael@0:       }
michael@0:     }
michael@0:   };
michael@0:   xhr.send();
michael@0:   this._xhr = xhr;
michael@0: }
michael@0: 
michael@0: URLFetcher.prototype = {
michael@0:   _isAborted: false,
michael@0:   ontimeout: function() {},
michael@0:   onerror: function() {},
michael@0:   abort: function() {
michael@0:     if (!this._isAborted) {
michael@0:       this._isAborted = true;
michael@0:       this._xhr.abort();
michael@0:     }
michael@0:   },
michael@0: }
michael@0: 
michael@0: function LoginObserver(captivePortalDetector) {
michael@0:   const LOGIN_OBSERVER_STATE_DETACHED = 0; /* Should not monitor network activity since no ongoing login procedure */
michael@0:   const LOGIN_OBSERVER_STATE_IDLE = 1; /* No network activity currently, waiting for a longer enough idle period */
michael@0:   const LOGIN_OBSERVER_STATE_BURST = 2; /* Network activity is detected, probably caused by a login procedure */
michael@0:   const LOGIN_OBSERVER_STATE_VERIFY_NEEDED = 3; /* Verifing network accessiblity is required after a long enough idle */
michael@0:   const LOGIN_OBSERVER_STATE_VERIFYING = 4; /* LoginObserver is probing if public network is available */
michael@0: 
michael@0:   let state = LOGIN_OBSERVER_STATE_DETACHED;
michael@0: 
michael@0:   let timer = Cc['@mozilla.org/timer;1'].createInstance(Ci.nsITimer);
michael@0:   let activityDistributor = Cc['@mozilla.org/network/http-activity-distributor;1']
michael@0:                               .getService(Ci.nsIHttpActivityDistributor);
michael@0:   let urlFetcher = null;
michael@0: 
michael@0:   let pageCheckingDone = function pageCheckingDone() {
michael@0:     if (state === LOGIN_OBSERVER_STATE_VERIFYING) {
michael@0:       urlFetcher = null;
michael@0:       // Finish polling the canonical site, switch back to idle state and
michael@0:       // waiting for next burst
michael@0:       state = LOGIN_OBSERVER_STATE_IDLE;
michael@0:       timer.initWithCallback(observer,
michael@0:                              captivePortalDetector._pollingTime,
michael@0:                              timer.TYPE_ONE_SHOT);
michael@0:     }
michael@0:   };
michael@0: 
michael@0:   let checkPageContent = function checkPageContent() {
michael@0:     debug("checking if public network is available after the login procedure");
michael@0: 
michael@0:     urlFetcher = new URLFetcher(captivePortalDetector._canonicalSiteURL,
michael@0:                                 captivePortalDetector._maxWaitingTime);
michael@0:     urlFetcher.ontimeout = pageCheckingDone;
michael@0:     urlFetcher.onerror = pageCheckingDone;
michael@0:     urlFetcher.onsuccess = function (content) {
michael@0:       if (captivePortalDetector.validateContent(content)) {
michael@0:         urlFetcher = null;
michael@0:         captivePortalDetector.executeCallback(true);
michael@0:       } else {
michael@0:         pageCheckingDone();
michael@0:       }
michael@0:     };
michael@0:     urlFetcher.onredirectorerror = pageCheckingDone;
michael@0:   };
michael@0: 
michael@0:   // Public interface of LoginObserver
michael@0:   let observer = {
michael@0:     QueryInterface: XPCOMUtils.generateQI([Ci.nsIHttpActivityOberver,
michael@0:                                            Ci.nsITimerCallback]),
michael@0: 
michael@0:     attach: function attach() {
michael@0:       if (state === LOGIN_OBSERVER_STATE_DETACHED) {
michael@0:         activityDistributor.addObserver(this);
michael@0:         state = LOGIN_OBSERVER_STATE_IDLE;
michael@0:         timer.initWithCallback(this,
michael@0:                                captivePortalDetector._pollingTime,
michael@0:                                timer.TYPE_ONE_SHOT);
michael@0:         debug('attach HttpObserver for login activity');
michael@0:       }
michael@0:     },
michael@0: 
michael@0:     detach: function detach() {
michael@0:       if (state !== LOGIN_OBSERVER_STATE_DETACHED) {
michael@0:         if (urlFetcher) {
michael@0:           urlFetcher.abort();
michael@0:           urlFetcher = null;
michael@0:         }
michael@0:         activityDistributor.removeObserver(this);
michael@0:         timer.cancel();
michael@0:         state = LOGIN_OBSERVER_STATE_DETACHED;
michael@0:         debug('detach HttpObserver for login activity');
michael@0:       }
michael@0:     },
michael@0: 
michael@0:     /*
michael@0:      * Treat all HTTP transactions as captive portal login activities.
michael@0:      */
michael@0:     observeActivity: function observeActivity(aHttpChannel, aActivityType,
michael@0:                                               aActivitySubtype, aTimestamp,
michael@0:                                               aExtraSizeData, aExtraStringData) {
michael@0:       if (aActivityType === Ci.nsIHttpActivityObserver.ACTIVITY_TYPE_HTTP_TRANSACTION
michael@0:           && aActivitySubtype === Ci.nsIHttpActivityObserver.ACTIVITY_SUBTYPE_RESPONSE_COMPLETE) {
michael@0:         switch (state) {
michael@0:           case LOGIN_OBSERVER_STATE_IDLE:
michael@0:           case LOGIN_OBSERVER_STATE_VERIFY_NEEDED:
michael@0:             state = LOGIN_OBSERVER_STATE_BURST;
michael@0:             break;
michael@0:           default:
michael@0:             break;
michael@0:         }
michael@0:       }
michael@0:     },
michael@0: 
michael@0:     /*
michael@0:      * Check if login activity is finished according to HTTP burst.
michael@0:      */
michael@0:     notify : function notify() {
michael@0:       switch(state) {
michael@0:         case LOGIN_OBSERVER_STATE_BURST:
michael@0:           // Wait while network stays idle for a short period
michael@0:           state = LOGIN_OBSERVER_STATE_VERIFY_NEEDED;
michael@0:           // Fall though to start polling timer
michael@0:         case LOGIN_OBSERVER_STATE_IDLE:
michael@0:           timer.initWithCallback(this,
michael@0:                                  captivePortalDetector._pollingTime,
michael@0:                                  timer.TYPE_ONE_SHOT);
michael@0:           break;
michael@0:         case LOGIN_OBSERVER_STATE_VERIFY_NEEDED:
michael@0:           // Polling the canonical website since network stays idle for a while
michael@0:           state = LOGIN_OBSERVER_STATE_VERIFYING;
michael@0:           checkPageContent();
michael@0:           break;
michael@0: 
michael@0:         default:
michael@0:           break;
michael@0:       }
michael@0:     },
michael@0:   };
michael@0: 
michael@0:   return observer;
michael@0: }
michael@0: 
michael@0: function CaptivePortalDetector() {
michael@0:   // Load preference
michael@0:   this._canonicalSiteURL = null;
michael@0:   this._canonicalSiteExpectedContent = null;
michael@0: 
michael@0:   try {
michael@0:     this._canonicalSiteURL =
michael@0:       Services.prefs.getCharPref('captivedetect.canonicalURL');
michael@0:     this._canonicalSiteExpectedContent =
michael@0:       Services.prefs.getCharPref('captivedetect.canonicalContent');
michael@0:   } catch(e) {
michael@0:     debug('canonicalURL or canonicalContent not set.')
michael@0:   }
michael@0: 
michael@0:   this._maxWaitingTime =
michael@0:     Services.prefs.getIntPref('captivedetect.maxWaitingTime');
michael@0:   this._pollingTime =
michael@0:     Services.prefs.getIntPref('captivedetect.pollingTime');
michael@0:   this._maxRetryCount =
michael@0:     Services.prefs.getIntPref('captivedetect.maxRetryCount');
michael@0:   debug('Load Prefs {site=' + this._canonicalSiteURL + ',content='
michael@0:         + this._canonicalSiteExpectedContent + ',time=' + this._maxWaitingTime
michael@0:         + "max-retry=" + this._maxRetryCount + '}');
michael@0: 
michael@0:   // Create HttpObserver for monitoring the login procedure
michael@0:   this._loginObserver = LoginObserver(this);
michael@0: 
michael@0:   this._nextRequestId = 0;
michael@0:   this._runningRequest = null;
michael@0:   this._requestQueue = []; // Maintain a progress table, store callbacks and the ongoing XHR
michael@0:   this._interfaceNames = {}; // Maintain names of the requested network interfaces
michael@0: 
michael@0:   debug('CaptiveProtalDetector initiated, waitng for network connection established');
michael@0: }
michael@0: 
michael@0: CaptivePortalDetector.prototype = {
michael@0:   classID:   kCAPTIVEPORTALDETECTOR_CID,
michael@0:   classInfo: XPCOMUtils.generateCI({classID: kCAPTIVEPORTALDETECTOR_CID,
michael@0:                                     contractID: kCAPTIVEPORTALDETECTOR_CONTRACTID,
michael@0:                                     classDescription: 'Captive Portal Detector',
michael@0:                                     interfaces: [Ci.nsICaptivePortalDetector]}),
michael@0:   QueryInterface: XPCOMUtils.generateQI([Ci.nsICaptivePortalDetector]),
michael@0: 
michael@0:   // nsICaptivePortalDetector
michael@0:   checkCaptivePortal: function checkCaptivePortal(aInterfaceName, aCallback) {
michael@0:     if (!this._canonicalSiteURL) {
michael@0:       throw Components.Exception('No canonical URL set up.');
michael@0:     }
michael@0: 
michael@0:     // Prevent multiple requests on a single network interface
michael@0:     if (this._interfaceNames[aInterfaceName]) {
michael@0:       throw Components.Exception('Do not allow multiple request on one interface: ' + aInterface);
michael@0:     }
michael@0: 
michael@0:     let request = {interfaceName: aInterfaceName};
michael@0:     if (aCallback) {
michael@0:       let callback = aCallback.QueryInterface(Ci.nsICaptivePortalCallback);
michael@0:       request['callback'] = callback;
michael@0:       request['retryCount'] = 0;
michael@0:     }
michael@0:     this._addRequest(request);
michael@0:   },
michael@0: 
michael@0:   abort: function abort(aInterfaceName) {
michael@0:     debug('abort for ' + aInterfaceName);
michael@0:     this._removeRequest(aInterfaceName);
michael@0:   },
michael@0: 
michael@0:   finishPreparation: function finishPreparation(aInterfaceName) {
michael@0:     debug('finish preparation phase for interface "' + aInterfaceName + '"');
michael@0:     if (!this._runningRequest
michael@0:         || this._runningRequest.interfaceName !== aInterfaceName) {
michael@0:       debug('invalid finishPreparation for ' + aInterfaceName);
michael@0:       throw Components.Exception('only first request is allowed to invoke |finishPreparation|');
michael@0:       return;
michael@0:     }
michael@0: 
michael@0:     this._startDetection();
michael@0:   },
michael@0: 
michael@0:   cancelLogin: function cancelLogin(eventId) {
michael@0:     debug('login canceled by user for request "' + eventId + '"');
michael@0:     // Captive portal login procedure is canceled by user
michael@0:     if (this._runningRequest && this._runningRequest.hasOwnProperty('eventId')) {
michael@0:       let id = this._runningRequest.eventId;
michael@0:       if (eventId === id) {
michael@0:         this.executeCallback(false);
michael@0:       }
michael@0:     }
michael@0:   },
michael@0: 
michael@0:   _applyDetection: function _applyDetection() {
michael@0:     debug('enter applyDetection('+ this._runningRequest.interfaceName + ')');
michael@0: 
michael@0:     // Execute network interface preparation
michael@0:     if (this._runningRequest.hasOwnProperty('callback')) {
michael@0:       this._runningRequest.callback.prepare();
michael@0:     } else {
michael@0:       this._startDetection();
michael@0:     }
michael@0:   },
michael@0: 
michael@0:   _startDetection: function _startDetection() {
michael@0:     debug('startDetection {site=' + this._canonicalSiteURL + ',content='
michael@0:           + this._canonicalSiteExpectedContent + ',time=' + this._maxWaitingTime + '}');
michael@0:     let self = this;
michael@0: 
michael@0:     let urlFetcher = new URLFetcher(this._canonicalSiteURL, this._maxWaitingTime);
michael@0: 
michael@0:     let mayRetry = this._mayRetry.bind(this);
michael@0: 
michael@0:     urlFetcher.ontimeout = mayRetry;
michael@0:     urlFetcher.onerror = mayRetry;
michael@0:     urlFetcher.onsuccess = function (content) {
michael@0:       if (self.validateContent(content)) {
michael@0:         self.executeCallback(true);
michael@0:       } else {
michael@0:         // Content of the canonical website has been overwrite
michael@0:         self._startLogin();
michael@0:       }
michael@0:     };
michael@0:     urlFetcher.onredirectorerror = function (status) {
michael@0:       if (status >= 300 && status <= 399) {
michael@0:         // The canonical website has been redirected to an unknown location
michael@0:         self._startLogin();
michael@0:       } else {
michael@0:         mayRetry();
michael@0:       }
michael@0:     };
michael@0: 
michael@0:     this._runningRequest['urlFetcher'] = urlFetcher;
michael@0:   },
michael@0: 
michael@0:   _startLogin: function _startLogin() {
michael@0:     let id = this._allocateRequestId();
michael@0:     let details = {
michael@0:       type: kOpenCaptivePortalLoginEvent,
michael@0:       id: id,
michael@0:       url: this._canonicalSiteURL,
michael@0:     };
michael@0:     this._loginObserver.attach();
michael@0:     this._runningRequest['eventId'] = id;
michael@0:     this._sendEvent(kOpenCaptivePortalLoginEvent, details);
michael@0:   },
michael@0: 
michael@0:   _mayRetry: function _mayRetry() {
michael@0:     if (this._runningRequest.retryCount++ < this._maxRetryCount) {
michael@0:       debug('retry-Detection: ' + this._runningRequest.retryCount + '/' + this._maxRetryCount);
michael@0:       this._startDetection();
michael@0:     } else {
michael@0:       this.executeCallback(true);
michael@0:     }
michael@0:   },
michael@0: 
michael@0:   executeCallback: function executeCallback(success) {
michael@0:     if (this._runningRequest) {
michael@0:       debug('callback executed');
michael@0:       if (this._runningRequest.hasOwnProperty('callback')) {
michael@0:         this._runningRequest.callback.complete(success);
michael@0:       }
michael@0: 
michael@0:       // Continue the following request
michael@0:       this._runningRequest['complete'] = true;
michael@0:       this._removeRequest(this._runningRequest.interfaceName);
michael@0:     }
michael@0:   },
michael@0: 
michael@0:   _sendEvent: function _sendEvent(topic, details) {
michael@0:     debug('sendEvent "' + JSON.stringify(details) + '"');
michael@0:     Services.obs.notifyObservers(this,
michael@0:                                  topic,
michael@0:                                  JSON.stringify(details));
michael@0:   },
michael@0: 
michael@0:   validateContent: function validateContent(content) {
michael@0:     debug('received content: ' + content);
michael@0:     return (content === this._canonicalSiteExpectedContent);
michael@0:   },
michael@0: 
michael@0:   _allocateRequestId: function _allocateRequestId() {
michael@0:     let newId = this._nextRequestId++;
michael@0:     return newId.toString();
michael@0:   },
michael@0: 
michael@0:   _runNextRequest: function _runNextRequest() {
michael@0:     let nextRequest = this._requestQueue.shift();
michael@0:     if (nextRequest) {
michael@0:       this._runningRequest = nextRequest;
michael@0:       this._applyDetection();
michael@0:     }
michael@0:   },
michael@0: 
michael@0:   _addRequest: function _addRequest(request) {
michael@0:     this._interfaceNames[request.interfaceName] = true;
michael@0:     this._requestQueue.push(request);
michael@0:     if (!this._runningRequest) {
michael@0:       this._runNextRequest();
michael@0:     }
michael@0:   },
michael@0: 
michael@0:   _removeRequest: function _removeRequest(aInterfaceName) {
michael@0:     if (!this._interfaceNames[aInterfaceName]) {
michael@0:       return;
michael@0:     }
michael@0: 
michael@0:     delete this._interfaceNames[aInterfaceName];
michael@0: 
michael@0:     if (this._runningRequest
michael@0:         && this._runningRequest.interfaceName === aInterfaceName) {
michael@0:       this._loginObserver.detach();
michael@0: 
michael@0:       if (!this._runningRequest.complete) {
michael@0:         // Abort the user login procedure
michael@0:         if (this._runningRequest.hasOwnProperty('eventId')) {
michael@0:           let details = {
michael@0:             type: kAbortCaptivePortalLoginEvent,
michael@0:             id: this._runningRequest.eventId
michael@0:           };
michael@0:           this._sendEvent(kAbortCaptivePortalLoginEvent, details);
michael@0:         }
michael@0: 
michael@0:         // Abort the ongoing HTTP request
michael@0:         if (this._runningRequest.hasOwnProperty('urlFetcher')) {
michael@0:           this._runningRequest.urlFetcher.abort();
michael@0:         }
michael@0:       }
michael@0: 
michael@0:       debug('remove running request');
michael@0:       this._runningRequest = null;
michael@0: 
michael@0:       // Continue next pending reqeust if the ongoing one has been aborted
michael@0:       this._runNextRequest();
michael@0:       return;
michael@0:     }
michael@0: 
michael@0:     // Check if a pending request has been aborted
michael@0:     for (let i = 0; i < this._requestQueue.length; i++) {
michael@0:       if (this._requestQueue[i].interfaceName == aInterfaceName) {
michael@0:         this._requestQueue.splice(i, 1);
michael@0: 
michael@0:         debug('remove pending request #' + i + ', remaining ' + this._requestQueue.length);
michael@0:         break;
michael@0:       }
michael@0:     }
michael@0:   },
michael@0: };
michael@0: 
michael@0: let debug;
michael@0: if (DEBUG) {
michael@0:   debug = function (s) {
michael@0:     dump('-*- CaptivePortalDetector component: ' + s + '\n');
michael@0:   };
michael@0: } else {
michael@0:   debug = function (s) {};
michael@0: }
michael@0: 
michael@0: this.NSGetFactory = XPCOMUtils.generateNSGetFactory([CaptivePortalDetector]);