Fix sqauth_read_password() for plugins running on the login_verified hook when the...
[squirrelmail.git] / functions / auth.php
CommitLineData
3c13b9fb 1<?php
2
35586184 3/**
4 * auth.php
5 *
867fed37 6 * Contains functions used to do authentication.
7 *
8 * Dependencies:
9 * functions/global.php
10 * functions/strings.php.
35586184 11 *
1977ab55 12 * @copyright 1999-2010 The SquirrelMail Project Team
4b4abf93 13 * @license http://opensource.org/licenses/gpl-license.php GNU Public License
31841a9e 14 * @version $Id$
d6c32258 15 * @package squirrelmail
35586184 16 */
17
3c13b9fb 18
8b52a4ca 19/**
cffbdf90 20 * Detect whether user is logged in
202bcbcc 21 *
22 * Function is similar to is_logged_in() function. If user is logged in, function
f7948940 23 * returns true. If user is not logged in or session is expired, function saves $_POST
de219480 24 * and PAGE_NAME in session and returns false. POST information is saved in
25 * 'session_expired_post' variable, PAGE_NAME is saved in 'session_expired_location'.
f7948940 26 *
7428254a 27 * This function optionally checks the referrer of this page request. If the
28 * administrator wants to impose a check that the referrer of this page request
29 * is another page on the same domain (otherwise, the page request is likely
30 * the result of a XSS or phishing attack), then they need to specify the
31 * acceptable referrer domain in a variable named $check_referrer in
32 * config/config.php (or the configuration tool) for which the value is
33 * usually the same as the $domain setting (for example:
34 * $check_referrer = 'example.com';
35 * However, in some cases (where proxy servers are in use, etc.), the
36 * acceptable referrer might be different. If $check_referrer is set to
37 * "###DOMAIN###", then the current value of $domain is used (useful in
38 * situations where $domain might change at runtime (when using the Login
39 * Manager plugin to host multiple domains with one SquirrelMail installation,
40 * for example)):
41 * $check_referrer = '###DOMAIN###';
42 * NOTE HOWEVER, that referrer checks are not foolproof - they can be spoofed
43 * by browsers, and some browsers intentionally don't send them, in which
44 * case SquirrelMail silently ignores referrer checks.
45 *
202bcbcc 46 * Script that uses this function instead of is_logged_in() function, must handle user
f7948940 47 * level messages.
48 * @return boolean
49 * @since 1.5.1
50 */
51function sqauth_is_logged_in() {
7428254a 52
53 global $check_referrer, $domain;
54 if (!sqgetGlobalVar('HTTP_REFERER', $referrer, SQ_SERVER)) $referrer = '';
55 if ($check_referrer == '###DOMAIN###') $check_referrer = $domain;
56 if (!empty($check_referrer)) {
57 $ssl_check_referrer = 'https://' . $check_referrer;
b0f43f13 58 $plain_check_referrer = 'http://' . $check_referrer;
7428254a 59 }
60 if (sqsession_is_registered('user_is_logged_in')
61 && (!$check_referrer || empty($referrer)
62 || ($check_referrer && !empty($referrer)
b0f43f13 63 && (strpos(strtolower($referrer), strtolower($plain_check_referrer)) === 0
7428254a 64 || strpos(strtolower($referrer), strtolower($ssl_check_referrer)) === 0)))) {
f7948940 65 return true;
cffbdf90 66 }
c6f28eb1 67
f74ec578 68 // First we store some information in the new session to prevent
69 // information-loss.
70 $session_expired_post = $_POST;
71 if (defined('PAGE_NAME'))
72 $session_expired_location = PAGE_NAME;
73 else
74 $session_expired_location = '';
75
76 if (!sqsession_is_registered('session_expired_post')) {
77 sqsession_register($session_expired_post,'session_expired_post');
78 }
79 if (!sqsession_is_registered('session_expired_location')) {
80 sqsession_register($session_expired_location,'session_expired_location');
81 }
82
83 session_write_close();
84
85 return false;
f7948940 86}
87
88/**
89 * Reads and decodes stored user password information
90 *
91 * Direct access to password information is deprecated.
92 * @return string password in plain text
93 * @since 1.5.1
94 */
95function sqauth_read_password() {
8747058a 96 global $currentHookName;
97 if ($currentHookName == 'login_verified') global $key;
98
f7948940 99 sqgetGlobalVar('key', $key, SQ_COOKIE);
100 sqgetGlobalVar('onetimepad', $onetimepad,SQ_SESSION);
101
102 return OneTimePadDecrypt($key, $onetimepad);
103}
104
105/**
106 * Saves or updates user password information
202bcbcc 107 *
45d5ec97 108 * This function is used to update the password information that
109 * SquirrelMail stores in the existing PHP session. It does NOT
110 * modify the password stored in the authentication system used
111 * by the IMAP server.
112 *
113 * This function must be called before any html output is started.
114 * Direct access to password information is deprecated. The saved
115 * password information is available only to the SquirrelMail script
116 * that is called/executed AFTER the current one. If your script
117 * needs access to the saved password after a sqauth_save_password()
118 * call, use the returned OTP encrypted key.
f7948940 119 *
f7948940 120 * @param string $pass password
45d5ec97 121 *
122 * @return string Password encrypted with OTP. In case the script
123 * wants to access the password information before
124 * the end of its execution.
125 *
f7948940 126 * @since 1.5.1
45d5ec97 127 *
f7948940 128 */
129function sqauth_save_password($pass) {
130 sqgetGlobalVar('base_uri', $base_uri, SQ_SESSION);
131
132 $onetimepad = OneTimePadCreate(strlen($pass));
133 sqsession_register($onetimepad,'onetimepad');
134 $key = OneTimePadEncrypt($pass, $onetimepad);
381ba319 135 sqsetcookie('key', $key, false, $base_uri);
136 return $key;
f7948940 137}
138
139/**
8b52a4ca 140 * Given the challenge from the server, supply the response using cram-md5 (See
141 * RFC 2195 for details)
142 *
143 * @param string $username User ID
144 * @param string $password User password supplied by User
145 * @param string $challenge The challenge supplied by the server
146 * @return string The response to be sent to the IMAP server
f7948940 147 * @since 1.4.0
8b52a4ca 148 */
47a29326 149function cram_md5_response ($username,$password,$challenge) {
8b52a4ca 150 $challenge=base64_decode($challenge);
151 $hash=bin2hex(hmac_md5($challenge,$password));
152 $response=base64_encode($username . " " . $hash) . "\r\n";
153 return $response;
47a29326 154}
155
8b52a4ca 156/**
157 * Return Digest-MD5 response.
158 * Given the challenge from the server, calculate and return the
159 * response-string for digest-md5 authentication. (See RFC 2831 for more
160 * details)
161 *
162 * @param string $username User ID
163 * @param string $password User password supplied by User
164 * @param string $challenge The challenge supplied by the server
165 * @param string $service The service name, usually 'imap'; it is used to
166 * define the digest-uri.
167 * @param string $host The host name, usually the server's FQDN; it is used to
168 * define the digest-uri.
b0434236 169 * @param string $authz Authorization ID (since 1.5.2)
8b52a4ca 170 * @return string The response to be sent to the IMAP server
f7948940 171 * @since 1.4.0
8b52a4ca 172 */
b0434236 173function digest_md5_response ($username,$password,$challenge,$service,$host,$authz='') {
ea321915 174 $result=digest_md5_parse_challenge($challenge);
b8f35815 175 //FIXME we should check that $result contains the expected values that we use below
62f7daa5 176
ea321915 177 // verify server supports qop=auth
178 // $qop = explode(",",$result['qop']);
179 //if (!in_array("auth",$qop)) {
47a29326 180 // rfc2831: client MUST fail if no qop methods supported
ea321915 181 // return false;
182 //}
183 $cnonce = base64_encode(bin2hex(hmac_md5(microtime())));
184 $ncount = "00000001";
185
186 /* This can be auth (authentication only), auth-int (integrity protection), or
187 auth-conf (confidentiality protection). Right now only auth is supported.
188 DO NOT CHANGE THIS VALUE */
189 $qop_value = "auth";
190
191 $digest_uri_value = $service . '/' . $host;
192
193 // build the $response_value
194 //FIXME This will probably break badly if a server sends more than one realm
195 $string_a1 = utf8_encode($username).":";
196 $string_a1 .= utf8_encode($result['realm']).":";
197 $string_a1 .= utf8_encode($password);
198 $string_a1 = hmac_md5($string_a1);
199 $A1 = $string_a1 . ":" . $result['nonce'] . ":" . $cnonce;
31dd6e3c 200 if(!empty($authz)) {
201 $A1 .= ":" . utf8_encode($authz);
202 }
ea321915 203 $A1 = bin2hex(hmac_md5($A1));
204 $A2 = "AUTHENTICATE:$digest_uri_value";
205 // If qop is auth-int or auth-conf, A2 gets a little extra
206 if ($qop_value != 'auth') {
207 $A2 .= ':00000000000000000000000000000000';
208 }
209 $A2 = bin2hex(hmac_md5($A2));
210
211 $string_response = $result['nonce'] . ':' . $ncount . ':' . $cnonce . ':' . $qop_value;
212 $response_value = bin2hex(hmac_md5($A1.":".$string_response.":".$A2));
213
214 $reply = 'charset=utf-8,username="' . $username . '",realm="' . $result["realm"] . '",';
215 $reply .= 'nonce="' . $result['nonce'] . '",nc=' . $ncount . ',cnonce="' . $cnonce . '",';
216 $reply .= "digest-uri=\"$digest_uri_value\",response=$response_value";
217 $reply .= ',qop=' . $qop_value;
b0434236 218 if(!empty($authz)) {
219 $reply .= ',authzid=' . $authz;
220 }
ea321915 221 $reply = base64_encode($reply);
222 return $reply . "\r\n";
62f7daa5 223
47a29326 224}
225
8b52a4ca 226/**
227 * Parse Digest-MD5 challenge.
228 * This function parses the challenge sent during DIGEST-MD5 authentication and
229 * returns an array. See the RFC for details on what's in the challenge string.
230 *
231 * @param string $challenge Digest-MD5 Challenge
232 * @return array Digest-MD5 challenge decoded data
f7948940 233 * @since 1.4.0
8b52a4ca 234 */
47a29326 235function digest_md5_parse_challenge($challenge) {
ea321915 236 $challenge=base64_decode($challenge);
b8f35815 237 $parsed = array();
238 while (!empty($challenge)) {
ea321915 239 if ($challenge{0} == ',') { // First char is a comma, must not be 1st time through loop
240 $challenge=substr($challenge,1);
241 }
242 $key=explode('=',$challenge,2);
243 $challenge=$key[1];
244 $key=$key[0];
245 if ($challenge{0} == '"') {
246 // We're in a quoted value
247 // Drop the first quote, since we don't care about it
248 $challenge=substr($challenge,1);
249 // Now explode() to the next quote, which is the end of our value
250 $val=explode('"',$challenge,2);
251 $challenge=$val[1]; // The rest of the challenge, work on it in next iteration of loop
252 $value=explode(',',$val[0]);
253 // Now, for those quoted values that are only 1 piece..
254 if (sizeof($value) == 1) {
255 $value=$value[0]; // Convert to non-array
256 }
257 } else {
258 // We're in a "simple" value - explode to next comma
259 $val=explode(',',$challenge,2);
260 if (isset($val[1])) {
261 $challenge=$val[1];
262 } else {
263 unset($challenge);
264 }
265 $value=$val[0];
266 }
267 $parsed["$key"]=$value;
268 } // End of while loop
269 return $parsed;
47a29326 270}
271
8b52a4ca 272/**
273 * Creates a HMAC digest that can be used for auth purposes
274 * See RFCs 2104, 2617, 2831
275 * Uses mhash() extension if available
276 *
277 * @param string $data Data to apply hash function to.
278 * @param string $key Optional key, which, if supplied, will be used to
279 * calculate data's HMAC.
280 * @return string HMAC Digest string
f7948940 281 * @since 1.4.0
8b52a4ca 282 */
1c6d997a 283function hmac_md5($data, $key='') {
639c7164 284 if (extension_loaded('mhash')) {
ea321915 285 if ($key== '') {
286 $mhash=mhash(MHASH_MD5,$data);
287 } else {
288 $mhash=mhash(MHASH_MD5,$data,$key);
289 }
290 return $mhash;
639c7164 291 }
292 if (!$key) {
ea321915 293 return pack('H*',md5($data));
639c7164 294 }
295 $key = str_pad($key,64,chr(0x00));
296 if (strlen($key) > 64) {
297 $key = pack("H*",md5($key));
298 }
299 $k_ipad = $key ^ str_repeat(chr(0x36), 64) ;
300 $k_opad = $key ^ str_repeat(chr(0x5c), 64) ;
1c6d997a 301 /* Heh, let's get recursive. */
302 $hmac=hmac_md5($k_opad . pack("H*",md5($k_ipad . $data)) );
639c7164 303 return $hmac;
304}
305
62f7daa5 306/**
9bd3b1e6 307 * Fillin user and password based on SMTP auth settings.
308 *
9bd3b1e6 309 * @param string $user Reference to SMTP username
310 * @param string $pass Reference to SMTP password (unencrypted)
0940b016 311 * @since 1.4.11
9bd3b1e6 312 */
313function get_smtp_user(&$user, &$pass) {
62f7daa5 314 global $username, $smtp_auth_mech,
9bd3b1e6 315 $smtp_sitewide_user, $smtp_sitewide_pass;
316
317 if ($smtp_auth_mech == 'none') {
318 $user = '';
319 $pass = '';
db84eecd 320 } elseif ( isset($smtp_sitewide_user) && isset($smtp_sitewide_pass) &&
321 !empty($smtp_sitewide_user)) {
9bd3b1e6 322 $user = $smtp_sitewide_user;
323 $pass = $smtp_sitewide_pass;
324 } else {
9bd3b1e6 325 $user = $username;
f7948940 326 $pass = sqauth_read_password();
9bd3b1e6 327 }
93917f92 328
329 // plugin authors note: override $user or $pass by
330 // directly changing the arguments array contents
331 // in your plugin e.g., $args[0] = 'new_username';
332 //
502b1f24 333 $temp = array(&$user, &$pass);
334 do_hook('smtp_auth', $temp);
9bd3b1e6 335}