| // Copyright (c) 2012 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. |
| |
| /** |
| * @fileoverview |
| * OAuth2 class that handles retrieval/storage of an OAuth2 token. |
| * |
| * Uses a content script to trampoline the OAuth redirect page back into the |
| * extension context. This works around the lack of native support for |
| * chrome-extensions in OAuth2. |
| */ |
| |
| // TODO(jamiewalch): Delete this code once Chromoting is a v2 app and uses the |
| // identity API (http://crbug.com/ 134213). |
| |
| 'use strict'; |
| |
| /** @suppress {duplicate} */ |
| var remoting = remoting || {}; |
| |
| /** @type {remoting.OAuth2} */ |
| remoting.oauth2 = null; |
| |
| |
| /** @constructor */ |
| remoting.OAuth2 = function() { |
| }; |
| |
| // Constants representing keys used for storing persistent state. |
| /** @private */ |
| remoting.OAuth2.prototype.KEY_REFRESH_TOKEN_ = 'oauth2-refresh-token'; |
| /** @private */ |
| remoting.OAuth2.prototype.KEY_ACCESS_TOKEN_ = 'oauth2-access-token'; |
| /** @private */ |
| remoting.OAuth2.prototype.KEY_XSRF_TOKEN_ = 'oauth2-xsrf-token'; |
| /** @private */ |
| remoting.OAuth2.prototype.KEY_EMAIL_ = 'remoting-email'; |
| |
| // Constants for parameters used in retrieving the OAuth2 credentials. |
| /** @private */ |
| remoting.OAuth2.prototype.SCOPE_ = |
| 'https://www.googleapis.com/auth/chromoting ' + |
| 'https://www.googleapis.com/auth/googletalk ' + |
| 'https://www.googleapis.com/auth/userinfo#email'; |
| |
| // Configurable URLs/strings. |
| /** @private |
| * @return {string} OAuth2 redirect URI. |
| */ |
| remoting.OAuth2.prototype.getRedirectUri_ = function() { |
| return remoting.settings.OAUTH2_REDIRECT_URL; |
| }; |
| |
| /** @private |
| * @return {string} API client ID. |
| */ |
| remoting.OAuth2.prototype.getClientId_ = function() { |
| return remoting.settings.OAUTH2_CLIENT_ID; |
| }; |
| |
| /** @private |
| * @return {string} API client secret. |
| */ |
| remoting.OAuth2.prototype.getClientSecret_ = function() { |
| return remoting.settings.OAUTH2_CLIENT_SECRET; |
| }; |
| |
| /** @private |
| * @return {string} OAuth2 authentication URL. |
| */ |
| remoting.OAuth2.prototype.getOAuth2AuthEndpoint_ = function() { |
| return remoting.settings.OAUTH2_BASE_URL + '/auth'; |
| }; |
| |
| /** @return {boolean} True if the app is already authenticated. */ |
| remoting.OAuth2.prototype.isAuthenticated = function() { |
| if (this.getRefreshToken()) { |
| return true; |
| } |
| return false; |
| }; |
| |
| /** |
| * Removes all storage, and effectively unauthenticates the user. |
| * |
| * @return {void} Nothing. |
| */ |
| remoting.OAuth2.prototype.clear = function() { |
| window.localStorage.removeItem(this.KEY_EMAIL_); |
| this.clearAccessToken_(); |
| this.clearRefreshToken_(); |
| }; |
| |
| /** |
| * Sets the refresh token. |
| * |
| * @param {string} token The new refresh token. |
| * @return {void} Nothing. |
| * @private |
| */ |
| remoting.OAuth2.prototype.setRefreshToken_ = function(token) { |
| window.localStorage.setItem(this.KEY_REFRESH_TOKEN_, escape(token)); |
| window.localStorage.removeItem(this.KEY_EMAIL_); |
| this.clearAccessToken_(); |
| }; |
| |
| /** |
| * @return {?string} The refresh token, if authenticated, or NULL. |
| */ |
| remoting.OAuth2.prototype.getRefreshToken = function() { |
| var value = window.localStorage.getItem(this.KEY_REFRESH_TOKEN_); |
| if (typeof value == 'string') { |
| return unescape(value); |
| } |
| return null; |
| }; |
| |
| /** |
| * Clears the refresh token. |
| * |
| * @return {void} Nothing. |
| * @private |
| */ |
| remoting.OAuth2.prototype.clearRefreshToken_ = function() { |
| window.localStorage.removeItem(this.KEY_REFRESH_TOKEN_); |
| }; |
| |
| /** |
| * @param {string} token The new access token. |
| * @param {number} expiration Expiration time in milliseconds since epoch. |
| * @return {void} Nothing. |
| * @private |
| */ |
| remoting.OAuth2.prototype.setAccessToken_ = function(token, expiration) { |
| // Offset expiration by 120 seconds so that we can guarantee that the token |
| // we return will be valid for at least 2 minutes. |
| // If the access token is to be useful, this object must make some |
| // guarantee as to how long the token will be valid for. |
| // The choice of 2 minutes is arbitrary, but that length of time |
| // is part of the contract satisfied by callWithToken(). |
| // Offset by a further 30 seconds to account for RTT issues. |
| var access_token = { |
| 'token': token, |
| 'expiration': (expiration - (120 + 30)) * 1000 + Date.now() |
| }; |
| window.localStorage.setItem(this.KEY_ACCESS_TOKEN_, |
| JSON.stringify(access_token)); |
| }; |
| |
| /** |
| * Returns the current access token, setting it to a invalid value if none |
| * existed before. |
| * |
| * @private |
| * @return {{token: string, expiration: number}} The current access token, or |
| * an invalid token if not authenticated. |
| */ |
| remoting.OAuth2.prototype.getAccessTokenInternal_ = function() { |
| if (!window.localStorage.getItem(this.KEY_ACCESS_TOKEN_)) { |
| // Always be able to return structured data. |
| this.setAccessToken_('', 0); |
| } |
| var accessToken = window.localStorage.getItem(this.KEY_ACCESS_TOKEN_); |
| if (typeof accessToken == 'string') { |
| var result = base.jsonParseSafe(accessToken); |
| if (result && 'token' in result && 'expiration' in result) { |
| return /** @type {{token: string, expiration: number}} */ result; |
| } |
| } |
| console.log('Invalid access token stored.'); |
| return {'token': '', 'expiration': 0}; |
| }; |
| |
| /** |
| * Returns true if the access token is expired, or otherwise invalid. |
| * |
| * Will throw if !isAuthenticated(). |
| * |
| * @return {boolean} True if a new access token is needed. |
| * @private |
| */ |
| remoting.OAuth2.prototype.needsNewAccessToken_ = function() { |
| if (!this.isAuthenticated()) { |
| throw 'Not Authenticated.'; |
| } |
| var access_token = this.getAccessTokenInternal_(); |
| if (!access_token['token']) { |
| return true; |
| } |
| if (Date.now() > access_token['expiration']) { |
| return true; |
| } |
| return false; |
| }; |
| |
| /** |
| * @return {void} Nothing. |
| * @private |
| */ |
| remoting.OAuth2.prototype.clearAccessToken_ = function() { |
| window.localStorage.removeItem(this.KEY_ACCESS_TOKEN_); |
| }; |
| |
| /** |
| * Update state based on token response from the OAuth2 /token endpoint. |
| * |
| * @param {function(string):void} onOk Called with the new access token. |
| * @param {string} accessToken Access token. |
| * @param {number} expiresIn Expiration time for the access token. |
| * @return {void} Nothing. |
| * @private |
| */ |
| remoting.OAuth2.prototype.onAccessToken_ = |
| function(onOk, accessToken, expiresIn) { |
| this.setAccessToken_(accessToken, expiresIn); |
| onOk(accessToken); |
| }; |
| |
| /** |
| * Update state based on token response from the OAuth2 /token endpoint. |
| * |
| * @param {function():void} onOk Called after the new tokens are stored. |
| * @param {string} refreshToken Refresh token. |
| * @param {string} accessToken Access token. |
| * @param {number} expiresIn Expiration time for the access token. |
| * @return {void} Nothing. |
| * @private |
| */ |
| remoting.OAuth2.prototype.onTokens_ = |
| function(onOk, refreshToken, accessToken, expiresIn) { |
| this.setAccessToken_(accessToken, expiresIn); |
| this.setRefreshToken_(refreshToken); |
| onOk(); |
| }; |
| |
| /** |
| * Redirect page to get a new OAuth2 Refresh Token. |
| * |
| * @param {function():void} onDone Completion callback. |
| * @return {void} Nothing. |
| */ |
| remoting.OAuth2.prototype.doAuthRedirect = function(onDone) { |
| /** @type {remoting.OAuth2} */ |
| var that = this; |
| var xsrf_token = base.generateXsrfToken(); |
| window.localStorage.setItem(this.KEY_XSRF_TOKEN_, xsrf_token); |
| var GET_CODE_URL = this.getOAuth2AuthEndpoint_() + '?' + |
| remoting.xhr.urlencodeParamHash({ |
| 'client_id': this.getClientId_(), |
| 'redirect_uri': this.getRedirectUri_(), |
| 'scope': this.SCOPE_, |
| 'state': xsrf_token, |
| 'response_type': 'code', |
| 'access_type': 'offline', |
| 'approval_prompt': 'force' |
| }); |
| |
| /** |
| * Processes the results of the oauth flow. |
| * |
| * @param {Object.<string, string>} message Dictionary containing the parsed |
| * OAuth redirect URL parameters. |
| */ |
| function oauth2MessageListener(message) { |
| if ('code' in message && 'state' in message) { |
| that.exchangeCodeForToken( |
| message['code'], message['state'], onDone); |
| } else { |
| if ('error' in message) { |
| console.error( |
| 'Could not obtain authorization code: ' + message['error']); |
| } else { |
| // We intentionally don't log the response - since we don't understand |
| // it, we can't tell if it has sensitive data. |
| console.error('Invalid oauth2 response.'); |
| } |
| } |
| chrome.extension.onMessage.removeListener(oauth2MessageListener); |
| } |
| chrome.extension.onMessage.addListener(oauth2MessageListener); |
| window.open(GET_CODE_URL, '_blank', 'location=yes,toolbar=no,menubar=no'); |
| }; |
| |
| /** |
| * Asynchronously exchanges an authorization code for a refresh token. |
| * |
| * @param {string} code The OAuth2 authorization code. |
| * @param {string} state The state parameter received from the OAuth redirect. |
| * @param {function():void} onDone Callback to invoke on completion. |
| * @return {void} Nothing. |
| */ |
| remoting.OAuth2.prototype.exchangeCodeForToken = function(code, state, onDone) { |
| var xsrf_token = window.localStorage.getItem(this.KEY_XSRF_TOKEN_); |
| window.localStorage.removeItem(this.KEY_XSRF_TOKEN_); |
| if (xsrf_token == undefined || state != xsrf_token) { |
| // Invalid XSRF token, or unexpected OAuth2 redirect. Abort. |
| onDone(); |
| } |
| /** @param {remoting.Error} error */ |
| var onError = function(error) { |
| console.error('Unable to exchange code for token: ', error); |
| }; |
| |
| remoting.OAuth2Api.exchangeCodeForTokens( |
| this.onTokens_.bind(this, onDone), onError, |
| this.getClientId_(), this.getClientSecret_(), code, |
| this.getRedirectUri_()); |
| }; |
| |
| /** |
| * Call a function with an access token, refreshing it first if necessary. |
| * The access token will remain valid for at least 2 minutes. |
| * |
| * @param {function(string):void} onOk Function to invoke with access token if |
| * an access token was successfully retrieved. |
| * @param {function(remoting.Error):void} onError Function to invoke with an |
| * error code on failure. |
| * @return {void} Nothing. |
| */ |
| remoting.OAuth2.prototype.callWithToken = function(onOk, onError) { |
| var refreshToken = this.getRefreshToken(); |
| if (refreshToken) { |
| if (this.needsNewAccessToken_()) { |
| remoting.OAuth2Api.refreshAccessToken( |
| this.onAccessToken_.bind(this, onOk), onError, |
| this.getClientId_(), this.getClientSecret_(), |
| refreshToken); |
| } else { |
| onOk(this.getAccessTokenInternal_()['token']); |
| } |
| } else { |
| onError(remoting.Error.NOT_AUTHENTICATED); |
| } |
| }; |
| |
| /** |
| * Get the user's email address. |
| * |
| * @param {function(string):void} onOk Callback invoked when the email |
| * address is available. |
| * @param {function(remoting.Error):void} onError Callback invoked if an |
| * error occurs. |
| * @return {void} Nothing. |
| */ |
| remoting.OAuth2.prototype.getEmail = function(onOk, onError) { |
| var cached = window.localStorage.getItem(this.KEY_EMAIL_); |
| if (typeof cached == 'string') { |
| onOk(cached); |
| return; |
| } |
| /** @type {remoting.OAuth2} */ |
| var that = this; |
| /** @param {string} email */ |
| var onResponse = function(email) { |
| window.localStorage.setItem(that.KEY_EMAIL_, email); |
| onOk(email); |
| }; |
| |
| this.callWithToken( |
| remoting.OAuth2Api.getEmail.bind(null, onResponse, onError), onError); |
| }; |
| |
| /** |
| * If the user's email address is cached, return it, otherwise return null. |
| * |
| * @return {?string} The email address, if it has been cached by a previous call |
| * to getEmail, otherwise null. |
| */ |
| remoting.OAuth2.prototype.getCachedEmail = function() { |
| var value = window.localStorage.getItem(this.KEY_EMAIL_); |
| if (typeof value == 'string') { |
| return value; |
| } |
| return null; |
| }; |