xref: /dokuwiki/lib/plugins/authldap/auth.php (revision 7c3df9b4f9d2f084b649907bf1f6c3a71454cf9d)
1<?php
2// must be run within Dokuwiki
3if(!defined('DOKU_INC')) die();
4
5/**
6 * LDAP authentication backend
7 *
8 * @license   GPL 2 (http://www.gnu.org/licenses/gpl.html)
9 * @author    Andreas Gohr <andi@splitbrain.org>
10 * @author    Chris Smith <chris@jalakaic.co.uk>
11 * @author    Jan Schumann <js@schumann-it.com>
12 */
13class auth_plugin_authldap extends DokuWiki_Auth_Plugin {
14    /* @var resource $con holds the LDAP connection*/
15    protected $con = null;
16
17    /* @var int $bound What type of connection does already exist? */
18    protected $bound = 0; // 0: anonymous, 1: user, 2: superuser
19
20    /* @var array $users User data cache */
21    protected $users = null;
22
23    /* @var array $_pattern User filter pattern */
24    protected $_pattern = null;
25
26    /**
27     * Constructor
28     */
29    public function __construct() {
30        parent::__construct();
31
32        // ldap extension is needed
33        if(!function_exists('ldap_connect')) {
34            $this->_debug("LDAP err: PHP LDAP extension not found.", -1, __LINE__, __FILE__);
35            $this->success = false;
36            return;
37        }
38
39        // Add the capabilities to change the password
40        $this->cando['modPass'] = true;
41    }
42
43    /**
44     * Check user+password
45     *
46     * Checks if the given user exists and the given
47     * plaintext password is correct by trying to bind
48     * to the LDAP server
49     *
50     * @author  Andreas Gohr <andi@splitbrain.org>
51     * @param string $user
52     * @param string $pass
53     * @return  bool
54     */
55    public function checkPass($user, $pass) {
56        // reject empty password
57        if(empty($pass)) return false;
58        if(!$this->_openLDAP()) return false;
59
60        // indirect user bind
61        if($this->getConf('binddn') && $this->getConf('bindpw')) {
62            // use superuser credentials
63            if(!@ldap_bind($this->con, $this->getConf('binddn'), $this->getConf('bindpw'))) {
64                $this->_debug('LDAP bind as superuser: '.htmlspecialchars(ldap_error($this->con)), 0, __LINE__, __FILE__);
65                return false;
66            }
67            $this->bound = 2;
68        } else if($this->getConf('binddn') &&
69            $this->getConf('usertree') &&
70            $this->getConf('userfilter')
71        ) {
72            // special bind string
73            $dn = $this->_makeFilter(
74                $this->getConf('binddn'),
75                array('user'=> $user, 'server'=> $this->getConf('server'))
76            );
77
78        } else if(strpos($this->getConf('usertree'), '%{user}')) {
79            // direct user bind
80            $dn = $this->_makeFilter(
81                $this->getConf('usertree'),
82                array('user'=> $user, 'server'=> $this->getConf('server'))
83            );
84
85        } else {
86            // Anonymous bind
87            if(!@ldap_bind($this->con)) {
88                msg("LDAP: can not bind anonymously", -1);
89                $this->_debug('LDAP anonymous bind: '.htmlspecialchars(ldap_error($this->con)), 0, __LINE__, __FILE__);
90                return false;
91            }
92        }
93
94        // Try to bind to with the dn if we have one.
95        if(!empty($dn)) {
96            // User/Password bind
97            if(!@ldap_bind($this->con, $dn, $pass)) {
98                $this->_debug("LDAP: bind with $dn failed", -1, __LINE__, __FILE__);
99                $this->_debug('LDAP user dn bind: '.htmlspecialchars(ldap_error($this->con)), 0, __LINE__, __FILE__);
100                return false;
101            }
102            $this->bound = 1;
103            return true;
104        } else {
105            // See if we can find the user
106            $info = $this->_getUserData($user, true);
107            if(empty($info['dn'])) {
108                return false;
109            } else {
110                $dn = $info['dn'];
111            }
112
113            // Try to bind with the dn provided
114            if(!@ldap_bind($this->con, $dn, $pass)) {
115                $this->_debug("LDAP: bind with $dn failed", -1, __LINE__, __FILE__);
116                $this->_debug('LDAP user bind: '.htmlspecialchars(ldap_error($this->con)), 0, __LINE__, __FILE__);
117                return false;
118            }
119            $this->bound = 1;
120            return true;
121        }
122    }
123
124    /**
125     * Return user info
126     *
127     * Returns info about the given user needs to contain
128     * at least these fields:
129     *
130     * name string  full name of the user
131     * mail string  email addres of the user
132     * grps array   list of groups the user is in
133     *
134     * This LDAP specific function returns the following
135     * addional fields:
136     *
137     * dn     string  distinguished name (DN)
138     * uid    string  Posix User ID
139     * inbind bool    for internal use - avoid loop in binding
140     *
141     * @author  Andreas Gohr <andi@splitbrain.org>
142     * @author  Trouble
143     * @author  Dan Allen <dan.j.allen@gmail.com>
144     * @author  <evaldas.auryla@pheur.org>
145     * @author  Stephane Chazelas <stephane.chazelas@emerson.com>
146     * @author  Steffen Schoch <schoch@dsb.net>
147     *
148     * @param   string $user
149     * @param   bool   $requireGroups (optional) - ignored, groups are always supplied by this plugin
150     * @return  array containing user data or false
151     */
152    public function getUserData($user, $requireGroups=true) {
153        return $this->_getUserData($user);
154    }
155
156    /**
157     * @param   string $user
158     * @param   bool   $inbind authldap specific, true if in bind phase
159     * @return  array containing user data or false
160     */
161    protected function _getUserData($user, $inbind = false) {
162        global $conf;
163        if(!$this->_openLDAP()) return false;
164
165        // force superuser bind if wanted and not bound as superuser yet
166        if($this->getConf('binddn') && $this->getConf('bindpw') && $this->bound < 2) {
167            // use superuser credentials
168            if(!@ldap_bind($this->con, $this->getConf('binddn'), $this->getConf('bindpw'))) {
169                $this->_debug('LDAP bind as superuser: '.htmlspecialchars(ldap_error($this->con)), 0, __LINE__, __FILE__);
170                return false;
171            }
172            $this->bound = 2;
173        } elseif($this->bound == 0 && !$inbind) {
174            // in some cases getUserData is called outside the authentication workflow
175            // eg. for sending email notification on subscribed pages. This data might not
176            // be accessible anonymously, so we try to rebind the current user here
177            list($loginuser, $loginsticky, $loginpass) = auth_getCookie();
178            if($loginuser && $loginpass) {
179                $loginpass = auth_decrypt($loginpass, auth_cookiesalt(!$loginsticky, true));
180                $this->checkPass($loginuser, $loginpass);
181            }
182        }
183
184        $info = array();
185        $info['user']   = $user;
186        $info['server'] = $this->getConf('server');
187
188        //get info for given user
189        $base = $this->_makeFilter($this->getConf('usertree'), $info);
190        if($this->getConf('userfilter')) {
191            $filter = $this->_makeFilter($this->getConf('userfilter'), $info);
192        } else {
193            $filter = "(ObjectClass=*)";
194        }
195
196        $sr     = $this->_ldapsearch($this->con, $base, $filter, $this->getConf('userscope'));
197        $result = @ldap_get_entries($this->con, $sr);
198        $this->_debug('LDAP user search: '.htmlspecialchars(ldap_error($this->con)), 0, __LINE__, __FILE__);
199        $this->_debug('LDAP search at: '.htmlspecialchars($base.' '.$filter), 0, __LINE__, __FILE__);
200
201        // Don't accept more or less than one response
202        if(!is_array($result) || $result['count'] != 1) {
203            return false; //user not found
204        }
205
206        $user_result = $result[0];
207        ldap_free_result($sr);
208
209        // general user info
210        $info['dn']   = $user_result['dn'];
211        $info['gid']  = $user_result['gidnumber'][0];
212        $info['mail'] = $user_result['mail'][0];
213        $info['name'] = $user_result['cn'][0];
214        $info['grps'] = array();
215
216        // overwrite if other attribs are specified.
217        if(is_array($this->getConf('mapping'))) {
218            foreach($this->getConf('mapping') as $localkey => $key) {
219                if(is_array($key)) {
220                    // use regexp to clean up user_result
221                    list($key, $regexp) = each($key);
222                    if($user_result[$key]) foreach($user_result[$key] as $grpkey => $grp) {
223                        if($grpkey !== 'count' && preg_match($regexp, $grp, $match)) {
224                            if($localkey == 'grps') {
225                                $info[$localkey][] = $match[1];
226                            } else {
227                                $info[$localkey] = $match[1];
228                            }
229                        }
230                    }
231                } else {
232                    $info[$localkey] = $user_result[$key][0];
233                }
234            }
235        }
236        $user_result = array_merge($info, $user_result);
237
238        //get groups for given user if grouptree is given
239        if($this->getConf('grouptree') || $this->getConf('groupfilter')) {
240            $base   = $this->_makeFilter($this->getConf('grouptree'), $user_result);
241            $filter = $this->_makeFilter($this->getConf('groupfilter'), $user_result);
242            $sr     = $this->_ldapsearch($this->con, $base, $filter, $this->getConf('groupscope'), array($this->getConf('groupkey')));
243            $this->_debug('LDAP group search: '.htmlspecialchars(ldap_error($this->con)), 0, __LINE__, __FILE__);
244            $this->_debug('LDAP search at: '.htmlspecialchars($base.' '.$filter), 0, __LINE__, __FILE__);
245
246            if(!$sr) {
247                msg("LDAP: Reading group memberships failed", -1);
248                return false;
249            }
250            $result = ldap_get_entries($this->con, $sr);
251            ldap_free_result($sr);
252
253            if(is_array($result)) foreach($result as $grp) {
254                if(!empty($grp[$this->getConf('groupkey')])) {
255                    $group = $grp[$this->getConf('groupkey')];
256                    if(is_array($group)){
257                        $group = $group[0];
258                    } else {
259                        $this->_debug('groupkey did not return a detailled result', 0, __LINE__, __FILE__);
260                    }
261                    if($group === '') continue;
262
263                    $this->_debug('LDAP usergroup: '.htmlspecialchars($group), 0, __LINE__, __FILE__);
264                    $info['grps'][] = $group;
265                }
266            }
267        }
268
269        // always add the default group to the list of groups
270        if(!$info['grps'] or !in_array($conf['defaultgroup'], $info['grps'])) {
271            $info['grps'][] = $conf['defaultgroup'];
272        }
273        return $info;
274    }
275
276    /**
277     * Definition of the function modifyUser in order to modify the password
278     */
279
280    function modifyUser($user,$changes){
281
282        // open the connection to the ldap
283        if(!$this->_openLDAP()){
284            msg('LDAP cannot connect: '. htmlspecialchars(ldap_error($this->con)));
285            return false;
286        }
287
288        // find the information about the user, in particular the "dn"
289        $info = $this->getUserData($user,true);
290        if(empty($info['dn'])) {
291            msg('LDAP cannot find your user dn');
292            return false;
293        }
294        $dn = $info['dn'];
295
296        // find the old password of the user
297        list($loginuser,$loginsticky,$loginpass) = auth_getCookie();
298        if ($loginuser !== null) { // the user is currently logged in
299            $secret = auth_cookiesalt(!$loginsticky, true);
300            $pass   = auth_decrypt($loginpass, $secret);
301
302            // bind with the ldap
303            if(!@ldap_bind($this->con, $dn, $pass)){
304                msg('LDAP user bind failed: '. htmlspecialchars($dn) .': '.htmlspecialchars(ldap_error($this->con)), 0, __LINE__, __FILE__);
305                return false;
306            }
307        } elseif ($this->getConf('binddn') && $this->getConf('bindpw')) {
308            // we are changing the password on behalf of the user (eg: forgotten password)
309            // bind with the superuser ldap
310            if (!@ldap_bind($this->con, $this->getConf('binddn'), $this->getConf('bindpw'))){
311                $this->_debug('LDAP bind as superuser: '.htmlspecialchars(ldap_error($this->con)), 0, __LINE__, __FILE__);
312                return false;
313            }
314        }
315        else {
316            return false; // no otherway
317        }
318
319        // Generate the salted hashed password for LDAP
320        $phash = new PassHash();
321        $hash = $phash->hash_ssha($changes['pass']);
322
323        // change the password
324        if(!@ldap_mod_replace($this->con, $dn,array('userpassword' => $hash))){
325            msg('LDAP mod replace failed: '. htmlspecialchars($dn) .': '.htmlspecialchars(ldap_error($this->con)));
326            return false;
327        }
328
329        return true;
330    }
331
332    /**
333     * Most values in LDAP are case-insensitive
334     *
335     * @return bool
336     */
337    public function isCaseSensitive() {
338        return false;
339    }
340
341    /**
342     * Bulk retrieval of user data
343     *
344     * @author  Dominik Eckelmann <dokuwiki@cosmocode.de>
345     * @param   int   $start     index of first user to be returned
346     * @param   int   $limit     max number of users to be returned
347     * @param   array $filter  array of field/pattern pairs, null for no filter
348     * @return  array of userinfo (refer getUserData for internal userinfo details)
349     */
350    function retrieveUsers($start = 0, $limit = 0, $filter = array()) {
351        if(!$this->_openLDAP()) return false;
352
353        if(is_null($this->users)) {
354            // Perform the search and grab all their details
355            if($this->getConf('userfilter')) {
356                $all_filter = str_replace('%{user}', '*', $this->getConf('userfilter'));
357            } else {
358                $all_filter = "(ObjectClass=*)";
359            }
360            $sr          = ldap_search($this->con, $this->getConf('usertree'), $all_filter);
361            $entries     = ldap_get_entries($this->con, $sr);
362            $users_array = array();
363            for($i = 0; $i < $entries["count"]; $i++) {
364                array_push($users_array, $entries[$i]["uid"][0]);
365            }
366            asort($users_array);
367            $result = $users_array;
368            if(!$result) return array();
369            $this->users = array_fill_keys($result, false);
370        }
371        $i     = 0;
372        $count = 0;
373        $this->_constructPattern($filter);
374        $result = array();
375
376        foreach($this->users as $user => &$info) {
377            if($i++ < $start) {
378                continue;
379            }
380            if($info === false) {
381                $info = $this->getUserData($user);
382            }
383            if($this->_filter($user, $info)) {
384                $result[$user] = $info;
385                if(($limit > 0) && (++$count >= $limit)) break;
386            }
387        }
388        return $result;
389    }
390
391    /**
392     * Make LDAP filter strings.
393     *
394     * Used by auth_getUserData to make the filter
395     * strings for grouptree and groupfilter
396     *
397     * @author  Troels Liebe Bentsen <tlb@rapanden.dk>
398     * @param   string $filter ldap search filter with placeholders
399     * @param   array  $placeholders placeholders to fill in
400     * @return  string
401     */
402    protected function _makeFilter($filter, $placeholders) {
403        preg_match_all("/%{([^}]+)/", $filter, $matches, PREG_PATTERN_ORDER);
404        //replace each match
405        foreach($matches[1] as $match) {
406            //take first element if array
407            if(is_array($placeholders[$match])) {
408                $value = $placeholders[$match][0];
409            } else {
410                $value = $placeholders[$match];
411            }
412            $value  = $this->_filterEscape($value);
413            $filter = str_replace('%{'.$match.'}', $value, $filter);
414        }
415        return $filter;
416    }
417
418    /**
419     * return true if $user + $info match $filter criteria, false otherwise
420     *
421     * @author Chris Smith <chris@jalakai.co.uk>
422     *
423     * @param  string $user the user's login name
424     * @param  array  $info the user's userinfo array
425     * @return bool
426     */
427    protected  function _filter($user, $info) {
428        foreach($this->_pattern as $item => $pattern) {
429            if($item == 'user') {
430                if(!preg_match($pattern, $user)) return false;
431            } else if($item == 'grps') {
432                if(!count(preg_grep($pattern, $info['grps']))) return false;
433            } else {
434                if(!preg_match($pattern, $info[$item])) return false;
435            }
436        }
437        return true;
438    }
439
440    /**
441     * Set the filter pattern
442     *
443     * @author Chris Smith <chris@jalakai.co.uk>
444     *
445     * @param $filter
446     * @return void
447     */
448    protected function _constructPattern($filter) {
449        $this->_pattern = array();
450        foreach($filter as $item => $pattern) {
451            $this->_pattern[$item] = '/'.str_replace('/', '\/', $pattern).'/i'; // allow regex characters
452        }
453    }
454
455    /**
456     * Escape a string to be used in a LDAP filter
457     *
458     * Ported from Perl's Net::LDAP::Util escape_filter_value
459     *
460     * @author Andreas Gohr
461     * @param  string $string
462     * @return string
463     */
464    protected function _filterEscape($string) {
465        return preg_replace(
466            '/([\x00-\x1F\*\(\)\\\\])/e',
467            '"\\\\\".join("",unpack("H2","$1"))',
468            $string
469        );
470    }
471
472    /**
473     * Opens a connection to the configured LDAP server and sets the wanted
474     * option on the connection
475     *
476     * @author  Andreas Gohr <andi@splitbrain.org>
477     */
478    protected function _openLDAP() {
479        if($this->con) return true; // connection already established
480
481        $this->bound = 0;
482
483        $port    = $this->getConf('port');
484        $bound   = false;
485        $servers = explode(',', $this->getConf('server'));
486        foreach($servers as $server) {
487            $server    = trim($server);
488            $this->con = @ldap_connect($server, $port);
489            if(!$this->con) {
490                continue;
491            }
492
493            /*
494             * When OpenLDAP 2.x.x is used, ldap_connect() will always return a resource as it does
495             * not actually connect but just initializes the connecting parameters. The actual
496             * connect happens with the next calls to ldap_* funcs, usually with ldap_bind().
497             *
498             * So we should try to bind to server in order to check its availability.
499             */
500
501            //set protocol version and dependend options
502            if($this->getConf('version')) {
503                if(!@ldap_set_option(
504                    $this->con, LDAP_OPT_PROTOCOL_VERSION,
505                    $this->getConf('version')
506                )
507                ) {
508                    msg('Setting LDAP Protocol version '.$this->getConf('version').' failed', -1);
509                    $this->_debug('LDAP version set: '.htmlspecialchars(ldap_error($this->con)), 0, __LINE__, __FILE__);
510                } else {
511                    //use TLS (needs version 3)
512                    if($this->getConf('starttls')) {
513                        if(!@ldap_start_tls($this->con)) {
514                            msg('Starting TLS failed', -1);
515                            $this->_debug('LDAP TLS set: '.htmlspecialchars(ldap_error($this->con)), 0, __LINE__, __FILE__);
516                        }
517                    }
518                    // needs version 3
519                    if($this->getConf('referrals')) {
520                        if(!@ldap_set_option(
521                            $this->con, LDAP_OPT_REFERRALS,
522                            $this->getConf('referrals')
523                        )
524                        ) {
525                            msg('Setting LDAP referrals to off failed', -1);
526                            $this->_debug('LDAP referal set: '.htmlspecialchars(ldap_error($this->con)), 0, __LINE__, __FILE__);
527                        }
528                    }
529                }
530            }
531
532            //set deref mode
533            if($this->getConf('deref')) {
534                if(!@ldap_set_option($this->con, LDAP_OPT_DEREF, $this->getConf('deref'))) {
535                    msg('Setting LDAP Deref mode '.$this->getConf('deref').' failed', -1);
536                    $this->_debug('LDAP deref set: '.htmlspecialchars(ldap_error($this->con)), 0, __LINE__, __FILE__);
537                }
538            }
539            /* As of PHP 5.3.0 we can set timeout to speedup skipping of invalid servers */
540            if(defined('LDAP_OPT_NETWORK_TIMEOUT')) {
541                ldap_set_option($this->con, LDAP_OPT_NETWORK_TIMEOUT, 1);
542            }
543
544            if($this->getConf('binddn') && $this->getConf('bindpw')) {
545                $bound = @ldap_bind($this->con, $this->getConf('binddn'), $this->getConf('bindpw'));
546                $this->bound = 2;
547            } else {
548                $bound = @ldap_bind($this->con);
549            }
550            if($bound) {
551                break;
552            }
553        }
554
555        if(!$bound) {
556            msg("LDAP: couldn't connect to LDAP server", -1);
557            return false;
558        }
559
560        $this->cando['getUsers'] = true;
561        return true;
562    }
563
564    /**
565     * Wraps around ldap_search, ldap_list or ldap_read depending on $scope
566     *
567     * @author Andreas Gohr <andi@splitbrain.org>
568     * @param resource   $link_identifier
569     * @param string     $base_dn
570     * @param string     $filter
571     * @param string     $scope can be 'base', 'one' or 'sub'
572     * @param null|array $attributes
573     * @param int        $attrsonly
574     * @param int        $sizelimit
575     * @return resource
576     */
577    protected function _ldapsearch($link_identifier, $base_dn, $filter, $scope = 'sub', $attributes = null,
578                         $attrsonly = 0, $sizelimit = 0) {
579        if(is_null($attributes)) $attributes = array();
580
581        if($scope == 'base') {
582            return @ldap_read(
583                $link_identifier, $base_dn, $filter, $attributes,
584                $attrsonly, $sizelimit
585            );
586        } elseif($scope == 'one') {
587            return @ldap_list(
588                $link_identifier, $base_dn, $filter, $attributes,
589                $attrsonly, $sizelimit
590            );
591        } else {
592            return @ldap_search(
593                $link_identifier, $base_dn, $filter, $attributes,
594                $attrsonly, $sizelimit
595            );
596        }
597    }
598
599    /**
600     * Wrapper around msg() but outputs only when debug is enabled
601     *
602     * @param string $message
603     * @param int    $err
604     * @param int    $line
605     * @param string $file
606     * @return void
607     */
608    protected function _debug($message, $err, $line, $file) {
609        if(!$this->getConf('debug')) return;
610        msg($message, $err, $line, $file);
611    }
612
613}
614