xref: /dokuwiki/lib/plugins/authldap/auth.php (revision 74981a4e680e4586b25ac0a679add084112cd604)
1<?php
2use dokuwiki\PassHash;
3use dokuwiki\Utf8\Sort;
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{
15    /* @var resource $con holds the LDAP connection */
16    protected $con;
17
18    /* @var int $bound What type of connection does already exist? */
19    protected $bound = 0; // 0: anonymous, 1: user, 2: superuser
20
21    /* @var array $users User data cache */
22    protected $users;
23
24    /* @var array $pattern User filter pattern */
25    protected $pattern;
26
27    /**
28     * Constructor
29     */
30    public function __construct()
31    {
32        parent::__construct();
33
34        // ldap extension is needed
35        if (!function_exists('ldap_connect')) {
36            $this->debug("LDAP err: PHP LDAP extension not found.", -1, __LINE__, __FILE__);
37            $this->success = false;
38            return;
39        }
40
41        // Add the capabilities to change the password
42        $this->cando['modPass'] = $this->getConf('modPass');
43    }
44
45    /**
46     * Check user+password
47     *
48     * Checks if the given user exists and the given
49     * plaintext password is correct by trying to bind
50     * to the LDAP server
51     *
52     * @param string $user
53     * @param string $pass
54     * @return  bool
55     * @author  Andreas Gohr <andi@splitbrain.org>
56     */
57    public function checkPass($user, $pass)
58    {
59        // reject empty password
60        if (empty($pass)) return false;
61        if (!$this->openLDAP()) return false;
62
63        // indirect user bind
64        if ($this->getConf('binddn') && $this->getConf('bindpw')) {
65            // use superuser credentials
66            if (!@ldap_bind($this->con, $this->getConf('binddn'), conf_decodeString($this->getConf('bindpw')))) {
67                $this->debug('LDAP bind as superuser: ' . hsc(ldap_error($this->con)), 0, __LINE__, __FILE__);
68                return false;
69            }
70            $this->bound = 2;
71        } elseif ($this->getConf('binddn') &&
72            $this->getConf('usertree') &&
73            $this->getConf('userfilter')
74        ) {
75            // special bind string
76            $dn = $this->makeFilter(
77                $this->getConf('binddn'),
78                ['user' => $user, 'server' => $this->getConf('server')]
79            );
80        } elseif (strpos($this->getConf('usertree'), '%{user}')) {
81            // direct user bind
82            $dn = $this->makeFilter(
83                $this->getConf('usertree'),
84                ['user' => $user, 'server' => $this->getConf('server')]
85            );
86        } elseif (!@ldap_bind($this->con)) {
87            // Anonymous bind
88            msg("LDAP: can not bind anonymously", -1);
89            $this->debug('LDAP anonymous bind: ' . hsc(ldap_error($this->con)), 0, __LINE__, __FILE__);
90            return false;
91        }
92
93        // Try to bind to with the dn if we have one.
94        if (!empty($dn)) {
95            // User/Password bind
96            if (!@ldap_bind($this->con, $dn, $pass)) {
97                $this->debug("LDAP: bind with $dn failed", -1, __LINE__, __FILE__);
98                $this->debug('LDAP user dn bind: ' . hsc(ldap_error($this->con)), 0, __LINE__, __FILE__);
99                return false;
100            }
101            $this->bound = 1;
102            return true;
103        } else {
104            // See if we can find the user
105            $info = $this->fetchUserData($user, true);
106            if (empty($info['dn'])) {
107                return false;
108            } else {
109                $dn = $info['dn'];
110            }
111
112            // Try to bind with the dn provided
113            if (!@ldap_bind($this->con, $dn, $pass)) {
114                $this->debug("LDAP: bind with $dn failed", -1, __LINE__, __FILE__);
115                $this->debug('LDAP user bind: ' . hsc(ldap_error($this->con)), 0, __LINE__, __FILE__);
116                return false;
117            }
118            $this->bound = 1;
119            return true;
120        }
121    }
122
123    /**
124     * Return user info
125     *
126     * Returns info about the given user needs to contain
127     * at least these fields:
128     *
129     * name string  full name of the user
130     * mail string  email addres of the user
131     * grps array   list of groups the user is in
132     *
133     * This LDAP specific function returns the following
134     * addional fields:
135     *
136     * dn     string  distinguished name (DN)
137     * uid    string  Posix User ID
138     * inbind bool    for internal use - avoid loop in binding
139     *
140     * @param string $user
141     * @param bool $requireGroups (optional) - ignored, groups are always supplied by this plugin
142     * @return  array containing user data or false
143     * @author  <evaldas.auryla@pheur.org>
144     * @author  Stephane Chazelas <stephane.chazelas@emerson.com>
145     * @author  Steffen Schoch <schoch@dsb.net>
146     *
147     * @author  Andreas Gohr <andi@splitbrain.org>
148     * @author  Trouble
149     * @author  Dan Allen <dan.j.allen@gmail.com>
150     */
151    public function getUserData($user, $requireGroups = true)
152    {
153        return $this->fetchUserData($user);
154    }
155
156    /**
157     * @param string $user
158     * @param bool $inbind authldap specific, true if in bind phase
159     * @return  array containing user data or false
160     */
161    protected function fetchUserData($user, $inbind = false)
162    {
163        global $conf;
164        if (!$this->openLDAP()) return [];
165
166        // force superuser bind if wanted and not bound as superuser yet
167        if ($this->getConf('binddn') && $this->getConf('bindpw') && $this->bound < 2) {
168            // use superuser credentials
169            if (!@ldap_bind($this->con, $this->getConf('binddn'), conf_decodeString($this->getConf('bindpw')))) {
170                $this->debug('LDAP bind as superuser: ' . hsc(ldap_error($this->con)), 0, __LINE__, __FILE__);
171                return [];
172            }
173            $this->bound = 2;
174        } elseif ($this->bound == 0 && !$inbind) {
175            // in some cases getUserData is called outside the authentication workflow
176            // eg. for sending email notification on subscribed pages. This data might not
177            // be accessible anonymously, so we try to rebind the current user here
178            [$loginuser, $loginsticky, $loginpass] = auth_getCookie();
179            if ($loginuser && $loginpass) {
180                $loginpass = auth_decrypt($loginpass, auth_cookiesalt(!$loginsticky, true));
181                $this->checkPass($loginuser, $loginpass);
182            }
183        }
184
185        $info = [];
186        $info['user'] = $user;
187        $this->debug('LDAP user to find: ' . hsc($info['user']), 0, __LINE__, __FILE__);
188
189        $info['server'] = $this->getConf('server');
190        $this->debug('LDAP Server: ' . hsc($info['server']), 0, __LINE__, __FILE__);
191
192        //get info for given user
193        $base = $this->makeFilter($this->getConf('usertree'), $info);
194        if ($this->getConf('userfilter')) {
195            $filter = $this->makeFilter($this->getConf('userfilter'), $info);
196        } else {
197            $filter = "(ObjectClass=*)";
198        }
199
200        $this->debug('LDAP Filter: ' . hsc($filter), 0, __LINE__, __FILE__);
201
202        $this->debug('LDAP user search: ' . hsc(ldap_error($this->con)), 0, __LINE__, __FILE__);
203        $this->debug('LDAP search at: ' . hsc($base . ' ' . $filter), 0, __LINE__, __FILE__);
204        $sr = $this->ldapSearch($this->con, $base, $filter, $this->getConf('userscope'), $this->getConf('attributes'));
205        if ($sr === false) {
206           $this->debug('User ldap_search failed. Check configuration.', 0, __LINE__, __FILE__);
207           return false;
208        }
209
210        $result = @ldap_get_entries($this->con, $sr);
211
212        // if result is not an array
213        if (!is_array($result)) {
214            // no objects found
215            $this->debug('LDAP search returned non-array result: ' . hsc(print($result)), -1, __LINE__, __FILE__);
216            return [];
217        }
218
219        // Don't accept more or less than one response
220        if ($result['count'] != 1) {
221            $this->debug(
222                'LDAP search returned ' . hsc($result['count']) . ' results while it should return 1!',
223                -1,
224                __LINE__,
225                __FILE__
226            );
227            //for($i = 0; $i < $result["count"]; $i++) {
228            //$this->_debug('result: '.hsc(print_r($result[$i])), 0, __LINE__, __FILE__);
229            //}
230            return [];
231        }
232
233        $this->debug('LDAP search found single result !', 0, __LINE__, __FILE__);
234
235        $user_result = $result[0];
236        ldap_free_result($sr);
237
238        // general user info
239        $info['dn'] = $user_result['dn'];
240        $info['gid'] = $user_result['gidnumber'][0] ?? null;
241        $info['mail'] = $user_result['mail'][0];
242        $info['name'] = $user_result['cn'][0];
243        $info['grps'] = [];
244
245        // overwrite if other attribs are specified.
246        if (is_array($this->getConf('mapping'))) {
247            foreach ($this->getConf('mapping') as $localkey => $key) {
248                if (is_array($key)) {
249                    // use regexp to clean up user_result
250                    // $key = array($key=>$regexp), only handles the first key-value
251                    $regexp = current($key);
252                    $key = key($key);
253                    if ($user_result[$key]) foreach ($user_result[$key] as $grpkey => $grp) {
254                        if ($grpkey !== 'count' && preg_match($regexp, $grp, $match)) {
255                            if ($localkey == 'grps') {
256                                $info[$localkey][] = $match[1];
257                            } else {
258                                $info[$localkey] = $match[1];
259                            }
260                        }
261                    }
262                } else {
263                    $info[$localkey] = $user_result[$key][0];
264                }
265            }
266        }
267        $user_result = array_merge($info, $user_result);
268
269        //get groups for given user if grouptree is given
270        if ($this->getConf('grouptree') || $this->getConf('groupfilter')) {
271            $base = $this->makeFilter($this->getConf('grouptree'), $user_result);
272            $filter = $this->makeFilter($this->getConf('groupfilter'), $user_result);
273            $sr = $this->ldapSearch(
274                $this->con,
275                $base,
276                $filter,
277                $this->getConf('groupscope'),
278                [$this->getConf('groupkey')]
279            );
280            $this->debug('LDAP group search: ' . hsc(ldap_error($this->con)), 0, __LINE__, __FILE__);
281            $this->debug('LDAP search at: ' . hsc($base . ' ' . $filter), 0, __LINE__, __FILE__);
282
283            if (!$sr) {
284                msg("LDAP: Reading group memberships failed", -1);
285                return [];
286            }
287            $result = ldap_get_entries($this->con, $sr);
288            ldap_free_result($sr);
289
290            if (is_array($result)) foreach ($result as $grp) {
291                if (!empty($grp[$this->getConf('groupkey')])) {
292                    $group = $grp[$this->getConf('groupkey')];
293                    if (is_array($group)) {
294                        $group = $group[0];
295                    } else {
296                        $this->debug('groupkey did not return a detailled result', 0, __LINE__, __FILE__);
297                    }
298                    if ($group === '') continue;
299
300                    $this->debug('LDAP usergroup: ' . hsc($group), 0, __LINE__, __FILE__);
301                    $info['grps'][] = $group;
302                }
303            }
304        }
305
306        // always add the default group to the list of groups
307        if (!$info['grps'] || !in_array($conf['defaultgroup'], $info['grps'])) {
308            $info['grps'][] = $conf['defaultgroup'];
309        }
310        return $info;
311    }
312
313    /**
314     * Definition of the function modifyUser in order to modify the password
315     *
316     * @param string $user nick of the user to be changed
317     * @param array $changes array of field/value pairs to be changed (password will be clear text)
318     * @return  bool   true on success, false on error
319     */
320    public function modifyUser($user, $changes)
321    {
322
323        // open the connection to the ldap
324        if (!$this->openLDAP()) {
325            $this->debug('LDAP cannot connect: ' . hsc(ldap_error($this->con)), 0, __LINE__, __FILE__);
326            return false;
327        }
328
329        // find the information about the user, in particular the "dn"
330        $info = $this->getUserData($user, true);
331        if (empty($info['dn'])) {
332            $this->debug('LDAP cannot find your user dn', 0, __LINE__, __FILE__);
333            return false;
334        }
335        $dn = $info['dn'];
336
337        // find the old password of the user
338        [$loginuser, $loginsticky, $loginpass] = auth_getCookie();
339        if ($loginuser !== null) { // the user is currently logged in
340            $secret = auth_cookiesalt(!$loginsticky, true);
341            $pass = auth_decrypt($loginpass, $secret);
342
343            // bind with the ldap
344            if (!@ldap_bind($this->con, $dn, $pass)) {
345                $this->debug(
346                    'LDAP user bind failed: ' . hsc($dn) . ': ' . hsc(ldap_error($this->con)),
347                    0,
348                    __LINE__,
349                    __FILE__
350                );
351                return false;
352            }
353        } elseif ($this->getConf('binddn') && $this->getConf('bindpw')) {
354            // we are changing the password on behalf of the user (eg: forgotten password)
355            // bind with the superuser ldap
356            if (!@ldap_bind($this->con, $this->getConf('binddn'), conf_decodeString($this->getConf('bindpw')))) {
357                $this->debug('LDAP bind as superuser: ' . hsc(ldap_error($this->con)), 0, __LINE__, __FILE__);
358                return false;
359            }
360        } else {
361            return false; // no otherway
362        }
363
364        // Generate the salted hashed password for LDAP
365        $phash = new PassHash();
366        $hash = $phash->hash_ssha($changes['pass']);
367
368        // change the password
369        if (!@ldap_mod_replace($this->con, $dn, ['userpassword' => $hash])) {
370            $this->debug(
371                'LDAP mod replace failed: ' . hsc($dn) . ': ' . hsc(ldap_error($this->con)),
372                0,
373                __LINE__,
374                __FILE__
375            );
376            return false;
377        }
378
379        return true;
380    }
381
382    /**
383     * Most values in LDAP are case-insensitive
384     *
385     * @return bool
386     */
387    public function isCaseSensitive()
388    {
389        return false;
390    }
391
392    /**
393     * Bulk retrieval of user data
394     *
395     * @param int $start index of first user to be returned
396     * @param int $limit max number of users to be returned
397     * @param array $filter array of field/pattern pairs, null for no filter
398     * @return  array of userinfo (refer getUserData for internal userinfo details)
399     * @author  Dominik Eckelmann <dokuwiki@cosmocode.de>
400     */
401    public function retrieveUsers($start = 0, $limit = 0, $filter = [])
402    {
403        if (!$this->openLDAP()) return [];
404
405        if (is_null($this->users)) {
406            // Perform the search and grab all their details
407            if ($this->getConf('userfilter')) {
408                $all_filter = str_replace('%{user}', '*', $this->getConf('userfilter'));
409            } else {
410                $all_filter = "(ObjectClass=*)";
411            }
412            $sr = ldap_search($this->con, $this->getConf('usertree'), $all_filter);
413            $entries = ldap_get_entries($this->con, $sr);
414            $users_array = [];
415            $userkey = $this->getConf('userkey');
416            for ($i = 0; $i < $entries["count"]; $i++) {
417                $users_array[] = $entries[$i][$userkey][0];
418            }
419            Sort::asort($users_array);
420            $result = $users_array;
421            if (!$result) return [];
422            $this->users = array_fill_keys($result, false);
423        }
424        $i = 0;
425        $count = 0;
426        $this->constructPattern($filter);
427        $result = [];
428
429        foreach ($this->users as $user => &$info) {
430            if ($i++ < $start) {
431                continue;
432            }
433            if ($info === false) {
434                $info = $this->getUserData($user);
435            }
436            if ($this->filter($user, $info)) {
437                $result[$user] = $info;
438                if (($limit > 0) && (++$count >= $limit)) break;
439            }
440        }
441        return $result;
442    }
443
444    /**
445     * Make LDAP filter strings.
446     *
447     * Used by auth_getUserData to make the filter
448     * strings for grouptree and groupfilter
449     *
450     * @param string $filter ldap search filter with placeholders
451     * @param array $placeholders placeholders to fill in
452     * @return  string
453     * @author  Troels Liebe Bentsen <tlb@rapanden.dk>
454     */
455    protected function makeFilter($filter, $placeholders)
456    {
457        preg_match_all("/%{([^}]+)/", $filter, $matches, PREG_PATTERN_ORDER);
458        //replace each match
459        foreach ($matches[1] as $match) {
460            //take first element if array
461            if (is_array($placeholders[$match])) {
462                $value = $placeholders[$match][0];
463            } else {
464                $value = $placeholders[$match];
465            }
466            $value = $this->filterEscape($value);
467            $filter = str_replace('%{' . $match . '}', $value, $filter);
468        }
469        return $filter;
470    }
471
472    /**
473     * return true if $user + $info match $filter criteria, false otherwise
474     *
475     * @param string $user the user's login name
476     * @param array $info the user's userinfo array
477     * @return bool
478     * @author Chris Smith <chris@jalakai.co.uk>
479     *
480     */
481    protected function filter($user, $info)
482    {
483        foreach ($this->pattern as $item => $pattern) {
484            if ($item == 'user') {
485                if (!preg_match($pattern, $user)) return false;
486            } elseif ($item == 'grps') {
487                if (!count(preg_grep($pattern, $info['grps']))) return false;
488            } elseif (!preg_match($pattern, $info[$item])) {
489                return false;
490            }
491        }
492        return true;
493    }
494
495    /**
496     * Set the filter pattern
497     *
498     * @param $filter
499     * @return void
500     * @author Chris Smith <chris@jalakai.co.uk>
501     *
502     */
503    protected function constructPattern($filter)
504    {
505        $this->pattern = [];
506        foreach ($filter as $item => $pattern) {
507            $this->pattern[$item] = '/' . str_replace('/', '\/', $pattern) . '/i'; // allow regex characters
508        }
509    }
510
511    /**
512     * Escape a string to be used in a LDAP filter
513     *
514     * Ported from Perl's Net::LDAP::Util escape_filter_value
515     *
516     * @param string $string
517     * @return string
518     * @author Andreas Gohr
519     */
520    protected function filterEscape($string)
521    {
522        // see https://github.com/adldap/adLDAP/issues/22
523        return preg_replace_callback(
524            '/([\x00-\x1F\*\(\)\\\\])/',
525            static fn($matches) => "\\" . implode("", unpack("H2", $matches[1])),
526            $string
527        );
528    }
529
530    /**
531     * Opens a connection to the configured LDAP server and sets the wanted
532     * option on the connection
533     *
534     * @author  Andreas Gohr <andi@splitbrain.org>
535     */
536    protected function openLDAP()
537    {
538        if ($this->con) return true; // connection already established
539
540        if ($this->getConf('debug')) {
541            ldap_set_option(null, LDAP_OPT_DEBUG_LEVEL, 7);
542        }
543
544        $this->bound = 0;
545
546        $port = $this->getConf('port');
547        $bound = false;
548        $servers = explode(',', $this->getConf('server'));
549        foreach ($servers as $server) {
550            $server = trim($server);
551            $this->con = @ldap_connect($server, $port);
552            if (!$this->con) {
553                continue;
554            }
555
556            /*
557             * When OpenLDAP 2.x.x is used, ldap_connect() will always return a resource as it does
558             * not actually connect but just initializes the connecting parameters. The actual
559             * connect happens with the next calls to ldap_* funcs, usually with ldap_bind().
560             *
561             * So we should try to bind to server in order to check its availability.
562             */
563
564            //set protocol version and dependend options
565            if ($this->getConf('version')) {
566                if (!@ldap_set_option(
567                    $this->con,
568                    LDAP_OPT_PROTOCOL_VERSION,
569                    $this->getConf('version')
570                )
571                ) {
572                    msg('Setting LDAP Protocol version ' . $this->getConf('version') . ' failed', -1);
573                    $this->debug('LDAP version set: ' . hsc(ldap_error($this->con)), 0, __LINE__, __FILE__);
574                } else {
575                    //use TLS (needs version 3)
576                    if ($this->getConf('starttls')) {
577                        if (!@ldap_start_tls($this->con)) {
578                            msg('Starting TLS failed', -1);
579                            $this->debug('LDAP TLS set: ' . hsc(ldap_error($this->con)), 0, __LINE__, __FILE__);
580                        }
581                    }
582                    // needs version 3
583                    if ($this->getConf('referrals') > -1) {
584                        if (!@ldap_set_option(
585                            $this->con,
586                            LDAP_OPT_REFERRALS,
587                            $this->getConf('referrals')
588                        )
589                        ) {
590                            msg('Setting LDAP referrals failed', -1);
591                            $this->debug('LDAP referal set: ' . hsc(ldap_error($this->con)), 0, __LINE__, __FILE__);
592                        }
593                    }
594                }
595            }
596
597            //set deref mode
598            if ($this->getConf('deref')) {
599                if (!@ldap_set_option($this->con, LDAP_OPT_DEREF, $this->getConf('deref'))) {
600                    msg('Setting LDAP Deref mode ' . $this->getConf('deref') . ' failed', -1);
601                    $this->debug('LDAP deref set: ' . hsc(ldap_error($this->con)), 0, __LINE__, __FILE__);
602                }
603            }
604            /* As of PHP 5.3.0 we can set timeout to speedup skipping of invalid servers */
605            if (defined('LDAP_OPT_NETWORK_TIMEOUT')) {
606                ldap_set_option($this->con, LDAP_OPT_NETWORK_TIMEOUT, 1);
607            }
608
609            if ($this->getConf('binddn') && $this->getConf('bindpw')) {
610                $bound = @ldap_bind($this->con, $this->getConf('binddn'), conf_decodeString($this->getConf('bindpw')));
611                $this->bound = 2;
612            } else {
613                $bound = @ldap_bind($this->con);
614            }
615            if ($bound) {
616                break;
617            }
618        }
619
620        if (!$bound) {
621            msg("LDAP: couldn't connect to LDAP server", -1);
622            $this->debug(ldap_error($this->con), 0, __LINE__, __FILE__);
623            return false;
624        }
625
626        $this->cando['getUsers'] = true;
627        return true;
628    }
629
630    /**
631     * Wraps around ldap_search, ldap_list or ldap_read depending on $scope
632     *
633     * @param resource $link_identifier
634     * @param string $base_dn
635     * @param string $filter
636     * @param string $scope can be 'base', 'one' or 'sub'
637     * @param null|array $attributes
638     * @param int $attrsonly
639     * @param int $sizelimit
640     * @return resource
641     * @author Andreas Gohr <andi@splitbrain.org>
642     */
643    protected function ldapSearch(
644        $link_identifier,
645        $base_dn,
646        $filter,
647        $scope = 'sub',
648        $attributes = null,
649        $attrsonly = 0,
650        $sizelimit = 0
651    )
652    {
653        if (is_null($attributes)) $attributes = [];
654
655        if ($scope == 'base') {
656            return @ldap_read(
657                $link_identifier,
658                $base_dn,
659                $filter,
660                $attributes,
661                $attrsonly,
662                $sizelimit
663            );
664        } elseif ($scope == 'one') {
665            return @ldap_list(
666                $link_identifier,
667                $base_dn,
668                $filter,
669                $attributes,
670                $attrsonly,
671                $sizelimit
672            );
673        } else {
674            return @ldap_search(
675                $link_identifier,
676                $base_dn,
677                $filter,
678                $attributes,
679                $attrsonly,
680                $sizelimit
681            );
682        }
683    }
684
685    /**
686     * Wrapper around msg() but outputs only when debug is enabled
687     *
688     * @param string $message
689     * @param int $err
690     * @param int $line
691     * @param string $file
692     * @return void
693     */
694    protected function debug($message, $err, $line, $file)
695    {
696        if (!$this->getConf('debug')) return;
697        msg($message, $err, $line, $file);
698    }
699}
700