Revert r27151 -- allows session fixation attacks.
[lhc/web/wiklou.git] / includes / api / ApiLogin.php
1 <?php
2
3 /*
4 * Created on Sep 19, 2006
5 *
6 * API for MediaWiki 1.8+
7 *
8 * Copyright (C) 2006-2007 Yuri Astrakhan <Firstname><Lastname>@gmail.com,
9 * Daniel Cannon (cannon dot danielc at gmail dot com)
10 *
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2 of the License, or
14 * (at your option) any later version.
15 *
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU General Public License for more details.
20 *
21 * You should have received a copy of the GNU General Public License along
22 * with this program; if not, write to the Free Software Foundation, Inc.,
23 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
24 * http://www.gnu.org/copyleft/gpl.html
25 */
26
27 if (!defined('MEDIAWIKI')) {
28 // Eclipse helper - will be ignored in production
29 require_once ('ApiBase.php');
30 }
31
32 /**
33 * Unit to authenticate log-in attempts to the current wiki.
34 *
35 * @addtogroup API
36 */
37 class ApiLogin extends ApiBase {
38
39 /**
40 * Time (in seconds) a user must wait after submitting
41 * a bad login (will be multiplied by the THROTTLE_FACTOR for each bad attempt)
42 */
43 const THROTTLE_TIME = 1;
44
45 /**
46 * The factor by which the wait-time in between authentication
47 * attempts is increased every failed attempt.
48 */
49 const THROTTLE_FACTOR = 2;
50
51 /**
52 * The maximum number of failed logins after which the wait increase stops.
53 */
54 const THOTTLE_MAX_COUNT = 10;
55
56 public function __construct($main, $action) {
57 parent :: __construct($main, $action, 'lg');
58 }
59
60 /**
61 * Executes the log-in attempt using the parameters passed. If
62 * the log-in succeeeds, it attaches a cookie to the session
63 * and outputs the user id, username, and session token. If a
64 * log-in fails, as the result of a bad password, a nonexistant
65 * user, or any other reason, the host is cached with an expiry
66 * and no log-in attempts will be accepted until that expiry
67 * is reached. The expiry is $this->mLoginThrottle.
68 *
69 * @access public
70 */
71 public function execute() {
72 $name = $password = $domain = null;
73 extract($this->extractRequestParams());
74
75 $result = array ();
76
77 // Make sure noone is trying to guess the password brut-force
78 $nextLoginIn = $this->getNextLoginTimeout();
79 if ($nextLoginIn > 0) {
80 $result['result'] = 'NeedToWait';
81 $result['details'] = "Please wait $nextLoginIn seconds before next log-in attempt";
82 $result['wait'] = $nextLoginIn;
83 $this->getResult()->addValue(null, 'login', $result);
84 return;
85 }
86
87 $params = new FauxRequest(array (
88 'wpName' => $name,
89 'wpPassword' => $password,
90 'wpDomain' => $domain,
91 'wpRemember' => ''
92 ));
93
94 $loginForm = new LoginForm($params);
95 switch ($loginForm->authenticateUserData()) {
96 case LoginForm :: SUCCESS :
97 global $wgUser, $wgCookiePrefix;
98
99 $wgUser->setOption('rememberpassword', 1);
100 $wgUser->setCookies();
101
102 $result['result'] = 'Success';
103 $result['lguserid'] = $_SESSION['wsUserID'];
104 $result['lgusername'] = $_SESSION['wsUserName'];
105 $result['lgtoken'] = $_SESSION['wsToken'];
106 $result['cookieprefix'] = $wgCookiePrefix;
107 $result['sessionid'] = $_COOKIE["{$wgCookiePrefix}_session"];
108 break;
109
110 case LoginForm :: NO_NAME :
111 $result['result'] = 'NoName';
112 break;
113 case LoginForm :: ILLEGAL :
114 $result['result'] = 'Illegal';
115 break;
116 case LoginForm :: WRONG_PLUGIN_PASS :
117 $result['result'] = 'WrongPluginPass';
118 break;
119 case LoginForm :: NOT_EXISTS :
120 $result['result'] = 'NotExists';
121 break;
122 case LoginForm :: WRONG_PASS :
123 $result['result'] = 'WrongPass';
124 break;
125 case LoginForm :: EMPTY_PASS :
126 $result['result'] = 'EmptyPass';
127 break;
128 default :
129 ApiBase :: dieDebug(__METHOD__, 'Unhandled case value');
130 }
131
132 if ($result['result'] != 'Success') {
133 $result['wait'] = $this->cacheBadLogin();
134 }
135 // if we were allowed to try to login, memcache is fine
136
137 $this->getResult()->addValue(null, 'login', $result);
138 }
139
140
141 /**
142 * Caches a bad-login attempt associated with the host and with an
143 * expiry of $this->mLoginThrottle. These are cached by a key
144 * separate from that used by the captcha system--as such, logging
145 * in through the standard interface will get you a legal session
146 * and cookies to prove it, but will not remove this entry.
147 *
148 * Returns the number of seconds until next login attempt will be allowed.
149 *
150 * @access private
151 */
152 private function cacheBadLogin() {
153 global $wgMemc;
154
155 $key = $this->getMemCacheKey();
156 $val = $wgMemc->get( $key );
157
158 $val['lastReqTime'] = time();
159 if (!isset($val['count'])) {
160 $val['count'] = 1;
161 } else {
162 $val['count'] = 1 + $val['count'];
163 }
164
165 $delay = ApiLogin::calculateDelay($val['count']);
166
167 $wgMemc->delete($key);
168 // Cache expiration should be the maximum timeout - to prevent a "try and wait" attack
169 $wgMemc->add( $key, $val, ApiLogin::calculateDelay(ApiLogin::THOTTLE_MAX_COUNT) );
170
171 return $delay;
172 }
173
174 /**
175 * How much time the client must wait before it will be
176 * allowed to try to log-in next.
177 * The return value is 0 if no wait is required.
178 */
179 private function getNextLoginTimeout() {
180 global $wgMemc;
181
182 $val = $wgMemc->get($this->getMemCacheKey());
183
184 $elapse = (time() - $val['lastReqTime']); // in seconds
185 $canRetryIn = ApiLogin::calculateDelay($val['count']) - $elapse;
186
187 return $canRetryIn < 0 ? 0 : $canRetryIn;
188 }
189
190 /**
191 * Based on the number of previously attempted logins, returns
192 * the delay (in seconds) when the next login attempt will be allowed.
193 */
194 private static function calculateDelay($count) {
195 // Defensive programming
196 $count = intval($count);
197 $count = $count < 1 ? 1 : $count;
198 $count = $count > self::THOTTLE_MAX_COUNT ? self::THOTTLE_MAX_COUNT : $count;
199
200 return self::THROTTLE_TIME + self::THROTTLE_TIME * ($count - 1) * self::THROTTLE_FACTOR;
201 }
202
203 /**
204 * Internal cache key for badlogin checks. Robbed from the
205 * ConfirmEdit extension and modified to use a key unique to the
206 * API login.3
207 *
208 * @return string
209 * @access private
210 */
211 private function getMemCacheKey() {
212 return wfMemcKey( 'apilogin', 'badlogin', 'ip', wfGetIP() );
213 }
214
215 protected function getAllowedParams() {
216 return array (
217 'name' => null,
218 'password' => null,
219 'domain' => null
220 );
221 }
222
223 protected function getParamDescription() {
224 return array (
225 'name' => 'User Name',
226 'password' => 'Password',
227 'domain' => 'Domain (optional)'
228 );
229 }
230
231 protected function getDescription() {
232 return array (
233 'This module is used to login and get the authentication tokens. ',
234 'In the event of a successful log-in, a cookie will be attached',
235 'to your session. In the event of a failed log-in, you will not ',
236 'be able to attempt another log-in through this method for 60 seconds.',
237 'This is to prevent password guessing by automated password crackers.'
238 );
239 }
240
241 protected function getExamples() {
242 return array(
243 'api.php?action=login&lgname=user&lgpassword=password'
244 );
245 }
246
247 public function getVersion() {
248 return __CLASS__ . ': $Id$';
249 }
250 }
251