MDL-57558 ldap: fix ldap_get_entries_moodle()
[moodle.git] / lib / ldaplib.php
CommitLineData
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1<?php
2
3/**
4 * ldaplib.php - LDAP functions & data library
5 *
6 * Library file of miscellaneous general-purpose LDAP functions and
7 * data structures, useful for both ldap authentication (or ldap based
8 * authentication like CAS) and enrolment plugins.
9 *
c090d7c9 10 * @author Iñaki Arenaza
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11 * @package core
12 * @subpackage lib
13 * @copyright 1999 onwards Martin Dougiamas http://dougiamas.com
c090d7c9 14 * @copyright 2010 onwards Iñaki Arenaza
78bfb562 15 * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
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16 */
17
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18defined('MOODLE_INTERNAL') || die();
19
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20// rootDSE is defined as the root of the directory data tree on a directory server.
21if (!defined('ROOTDSE')) {
22 define ('ROOTDSE', '');
23}
24
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25// Paged results control OID value.
26if (!defined('LDAP_PAGED_RESULTS_CONTROL')) {
27 define ('LDAP_PAGED_RESULTS_CONTROL', '1.2.840.113556.1.4.319');
28}
29
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30// Default page size when using LDAP paged results
31if (!defined('LDAP_DEFAULT_PAGESIZE')) {
32 define('LDAP_DEFAULT_PAGESIZE', 250);
33}
34
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35/**
36 * Returns predefined user types
37 *
38 * @return array of predefined user types
39 */
40function ldap_supported_usertypes() {
41 $types = array();
42 $types['edir'] = 'Novell Edirectory';
43 $types['rfc2307'] = 'posixAccount (rfc2307)';
44 $types['rfc2307bis'] = 'posixAccount (rfc2307bis)';
45 $types['samba'] = 'sambaSamAccount (v.3.0.7)';
46 $types['ad'] = 'MS ActiveDirectory';
47 $types['default'] = get_string('default');
48 return $types;
49}
50
51/**
52 * Initializes needed variables for ldap-module
53 *
54 * Uses names defined in ldap_supported_usertypes.
55 * $default is first defined as:
56 * $default['pseudoname'] = array(
57 * 'typename1' => 'value',
58 * 'typename2' => 'value'
59 * ....
60 * );
61 *
62 * @return array of default values
63 */
64function ldap_getdefaults() {
65 // All the values have to be written in lowercase, even if the
66 // standard LDAP attributes are mixed-case
67 $default['objectclass'] = array(
68 'edir' => 'user',
69 'rfc2307' => 'posixaccount',
70 'rfc2307bis' => 'posixaccount',
71 'samba' => 'sambasamaccount',
6514ced4 72 'ad' => '(samaccounttype=805306368)',
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73 'default' => '*'
74 );
75 $default['user_attribute'] = array(
76 'edir' => 'cn',
77 'rfc2307' => 'uid',
78 'rfc2307bis' => 'uid',
79 'samba' => 'uid',
80 'ad' => 'cn',
81 'default' => 'cn'
82 );
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83 $default['suspended_attribute'] = array(
84 'edir' => '',
85 'rfc2307' => '',
86 'rfc2307bis' => '',
87 'samba' => '',
88 'ad' => '',
89 'default' => ''
90 );
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91 $default['memberattribute'] = array(
92 'edir' => 'member',
93 'rfc2307' => 'member',
94 'rfc2307bis' => 'member',
95 'samba' => 'member',
96 'ad' => 'member',
97 'default' => 'member'
98 );
99 $default['memberattribute_isdn'] = array(
100 'edir' => '1',
101 'rfc2307' => '0',
102 'rfc2307bis' => '1',
103 'samba' => '0', // is this right?
104 'ad' => '1',
105 'default' => '0'
106 );
107 $default['expireattr'] = array (
108 'edir' => 'passwordexpirationtime',
109 'rfc2307' => 'shadowexpire',
110 'rfc2307bis' => 'shadowexpire',
111 'samba' => '', // No support yet
112 'ad' => 'pwdlastset',
113 'default' => ''
114 );
115 return $default;
116}
117
118/**
119 * Checks if user belongs to specific group(s) or is in a subtree.
120 *
121 * Returns true if user belongs to a group in grupdns string OR if the
122 * DN of the user is in a subtree of the DN provided as "group"
123 *
124 * @param mixed $ldapconnection A valid LDAP connection.
125 * @param string $userid LDAP user id (dn/cn/uid/...) to test membership for.
126 * @param array $group_dns arrary of group dn
127 * @param string $member_attrib the name of the membership attribute.
128 * @return boolean
129 *
130 */
131function ldap_isgroupmember($ldapconnection, $userid, $group_dns, $member_attrib) {
132 if (empty($ldapconnection) || empty($userid) || empty($group_dns) || empty($member_attrib)) {
133 return false;
134 }
135
136 $result = false;
137 foreach ($group_dns as $group) {
138 $group = trim($group);
139 if (empty($group)) {
140 continue;
141 }
142
143 // Check cheaply if the user's DN sits in a subtree of the
144 // "group" DN provided. Granted, this isn't a proper LDAP
145 // group, but it's a popular usage.
3e5f4b87 146 if (stripos(strrev(strtolower($userid)), strrev(strtolower($group))) === 0) {
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147 $result = true;
148 break;
149 }
150
151 $search = ldap_read($ldapconnection, $group,
152 '('.$member_attrib.'='.ldap_filter_addslashes($userid).')',
153 array($member_attrib));
154
155 if (!empty($search) && ldap_count_entries($ldapconnection, $search)) {
156 $info = ldap_get_entries_moodle($ldapconnection, $search);
157 if (count($info) > 0 ) {
158 // User is member of group
159 $result = true;
160 break;
161 }
162 }
163 }
164
165 return $result;
166}
167
168/**
169 * Tries connect to specified ldap servers. Returns a valid LDAP
170 * connection or false.
171 *
172 * @param string $host_url
173 * @param integer $ldap_version either 2 (LDAPv2) or 3 (LDAPv3).
174 * @param string $user_type the configured user type for this connection.
175 * @param string $bind_dn the binding user dn. If an emtpy string, anonymous binding is used.
176 * @param string $bind_pw the password for the binding user. Ignored for anonymous bindings.
177 * @param boolean $opt_deref whether to set LDAP_OPT_DEREF on this connection or not.
178 * @param string &$debuginfo the debugging information in case the connection fails.
326929d5 179 * @param boolean $start_tls whether to use LDAP with TLS (not to be confused with LDAP+SSL)
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180 * @return mixed connection result or false.
181 */
326929d5 182function ldap_connect_moodle($host_url, $ldap_version, $user_type, $bind_dn, $bind_pw, $opt_deref, &$debuginfo, $start_tls=false) {
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183 if (empty($host_url) || empty($ldap_version) || empty($user_type)) {
184 $debuginfo = 'No LDAP Host URL, Version or User Type specified in your LDAP settings';
185 return false;
186 }
187
188 $debuginfo = '';
189 $urls = explode(';', $host_url);
190 foreach ($urls as $server) {
191 $server = trim($server);
192 if (empty($server)) {
193 continue;
194 }
195
196 $connresult = ldap_connect($server); // ldap_connect returns ALWAYS true
197
198 if (!empty($ldap_version)) {
199 ldap_set_option($connresult, LDAP_OPT_PROTOCOL_VERSION, $ldap_version);
200 }
201
202 // Fix MDL-10921
203 if ($user_type === 'ad') {
204 ldap_set_option($connresult, LDAP_OPT_REFERRALS, 0);
205 }
206
207 if (!empty($opt_deref)) {
208 ldap_set_option($connresult, LDAP_OPT_DEREF, $opt_deref);
209 }
210
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211 if ($start_tls && (!ldap_start_tls($connresult))) {
212 $debuginfo .= "Server: '$server', Connection: '$connresult', STARTTLS failed.\n";
213 continue;
214 }
215
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216 if (!empty($bind_dn)) {
217 $bindresult = @ldap_bind($connresult, $bind_dn, $bind_pw);
218 } else {
219 // Bind anonymously
220 $bindresult = @ldap_bind($connresult);
221 }
222
223 if ($bindresult) {
224 return $connresult;
225 }
226
227 $debuginfo .= "Server: '$server', Connection: '$connresult', Bind result: '$bindresult'\n";
228 }
229
230 // If any of servers were alive we have already returned connection.
231 return false;
232}
233
234/**
235 * Search specified contexts for username and return the user dn like:
236 * cn=username,ou=suborg,o=org
237 *
238 * @param mixed $ldapconnection a valid LDAP connection.
239 * @param mixed $username username (external LDAP encoding, no db slashes).
240 * @param array $contexts contexts to look for the user.
241 * @param string $objectclass objectlass of the user (in LDAP filter syntax).
242 * @param string $search_attrib the attribute use to look for the user.
243 * @param boolean $search_sub whether to search subcontexts or not.
244 * @return mixed the user dn (external LDAP encoding, no db slashes) or false
245 *
246 */
247function ldap_find_userdn($ldapconnection, $username, $contexts, $objectclass, $search_attrib, $search_sub) {
248 if (empty($ldapconnection) || empty($username) || empty($contexts) || empty($objectclass) || empty($search_attrib)) {
249 return false;
250 }
251
252 // Default return value
253 $ldap_user_dn = false;
254
255 // Get all contexts and look for first matching user
256 foreach ($contexts as $context) {
257 $context = trim($context);
258 if (empty($context)) {
259 continue;
260 }
261
262 if ($search_sub) {
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263 $ldap_result = @ldap_search($ldapconnection, $context,
264 '(&'.$objectclass.'('.$search_attrib.'='.ldap_filter_addslashes($username).'))',
265 array($search_attrib));
5704585c 266 } else {
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267 $ldap_result = @ldap_list($ldapconnection, $context,
268 '(&'.$objectclass.'('.$search_attrib.'='.ldap_filter_addslashes($username).'))',
269 array($search_attrib));
270 }
271
272 if (!$ldap_result) {
273 continue; // Not found in this context.
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274 }
275
276 $entry = ldap_first_entry($ldapconnection, $ldap_result);
277 if ($entry) {
278 $ldap_user_dn = ldap_get_dn($ldapconnection, $entry);
279 break;
280 }
281 }
282
283 return $ldap_user_dn;
284}
285
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286/**
287 * Normalise the supplied objectclass filter.
288 *
289 * This normalisation is a rudimentary attempt to format the objectclass filter correctly.
290 *
291 * @param string $objectclass The objectclass to normalise
292 * @param string $default The default objectclass value to use if no objectclass was supplied
293 * @return string The normalised objectclass.
294 */
295function ldap_normalise_objectclass($objectclass, $default = '*') {
296 if (empty($objectclass)) {
297 // Can't send empty filter.
298 $return = sprintf('(objectClass=%s)', $default);
299 } else if (stripos($objectclass, 'objectClass=') === 0) {
300 // Value is 'objectClass=some-string-here', so just add () around the value (filter _must_ have them).
301 $return = sprintf('(%s)', $objectclass);
302 } else if (stripos($objectclass, '(') !== 0) {
303 // Value is 'some-string-not-starting-with-left-parentheses', which is assumed to be the objectClass matching value.
304 // Build a valid filter using the value it.
305 $return = sprintf('(objectClass=%s)', $objectclass);
306 } else {
307 // There is an additional possible value '(some-string-here)', that can be used to specify any valid filter
308 // string, to select subsets of users based on any criteria.
309 //
310 // For example, we could select the users whose objectClass is 'user' and have the 'enabledMoodleUser'
311 // attribute, with something like:
312 //
313 // (&(objectClass=user)(enabledMoodleUser=1))
314 //
315 // In this particular case we don't need to do anything, so leave $this->config->objectclass as is.
316 $return = $objectclass;
317 }
318
319 return $return;
320}
321
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322/**
323 * Returns values like ldap_get_entries but is binary compatible and
324 * returns all attributes as array.
325 *
326 * @param mixed $ldapconnection A valid LDAP connection
327 * @param mixed $searchresult A search result from ldap_search, ldap_list, etc.
328 * @return array ldap-entries with lower-cased attributes as indexes
329 */
330function ldap_get_entries_moodle($ldapconnection, $searchresult) {
331 if (empty($ldapconnection) || empty($searchresult)) {
332 return array();
333 }
334
335 $i = 0;
336 $result = array();
337 $entry = ldap_first_entry($ldapconnection, $searchresult);
338 if (!$entry) {
339 return array();
340 }
341 do {
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342 $attributes = array();
343 $attribute = ldap_first_attribute($ldapconnection, $entry);
344 while ($attribute !== false) {
345 $attributes[] = strtolower($attribute); // Attribute names don't usually contain non-ASCII characters.
346 $attribute = ldap_next_attribute($ldapconnection, $entry);
347 }
348 foreach ($attributes as $attribute) {
349 $values = ldap_get_values_len($ldapconnection, $entry, $attribute);
5704585c 350 if (is_array($values)) {
67bebb69 351 $result[$i][$attribute] = $values;
5704585c 352 } else {
67bebb69 353 $result[$i][$attribute] = array($values);
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354 }
355 }
356 $i++;
357 } while ($entry = ldap_next_entry($ldapconnection, $entry));
358
359 return ($result);
360}
361
362/**
363 * Quote control characters in texts used in LDAP filters - see RFC 4515/2254
364 *
365 * @param string filter string to quote
366 * @return string the filter string quoted
367 */
368function ldap_filter_addslashes($text) {
369 $text = str_replace('\\', '\\5c', $text);
370 $text = str_replace(array('*', '(', ')', "\0"),
371 array('\\2a', '\\28', '\\29', '\\00'), $text);
372 return $text;
373}
374
375if(!defined('LDAP_DN_SPECIAL_CHARS')) {
376 define('LDAP_DN_SPECIAL_CHARS', 0);
377}
378if(!defined('LDAP_DN_SPECIAL_CHARS_QUOTED_NUM')) {
379 define('LDAP_DN_SPECIAL_CHARS_QUOTED_NUM', 1);
380}
381if(!defined('LDAP_DN_SPECIAL_CHARS_QUOTED_ALPHA')) {
382 define('LDAP_DN_SPECIAL_CHARS_QUOTED_ALPHA', 2);
383}
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384if(!defined('LDAP_DN_SPECIAL_CHARS_QUOTED_ALPHA_REGEX')) {
385 define('LDAP_DN_SPECIAL_CHARS_QUOTED_ALPHA_REGEX', 3);
386}
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387
388/**
389 * The order of the special characters in these arrays _IS IMPORTANT_.
390 * Make sure '\\5C' (and '\\') are the first elements of the arrays.
391 * Otherwise we'll double replace '\' with '\5C' which is Bad(tm)
392 */
393function ldap_get_dn_special_chars() {
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394 static $specialchars = null;
395
396 if ($specialchars !== null) {
397 return $specialchars;
398 }
399
400 $specialchars = array (
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401 LDAP_DN_SPECIAL_CHARS => array('\\', ' ', '"', '#', '+', ',', ';', '<', '=', '>', "\0"),
402 LDAP_DN_SPECIAL_CHARS_QUOTED_NUM => array('\\5c','\\20','\\22','\\23','\\2b','\\2c','\\3b','\\3c','\\3d','\\3e','\\00'),
98077377 403 LDAP_DN_SPECIAL_CHARS_QUOTED_ALPHA => array('\\\\','\\ ', '\\"', '\\#', '\\+', '\\,', '\\;', '\\<', '\\=', '\\>', '\\00'),
5704585c 404 );
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405 $alpharegex = implode('|', array_map (function ($expr) { return preg_quote($expr); },
406 $specialchars[LDAP_DN_SPECIAL_CHARS_QUOTED_ALPHA]));
407 $specialchars[LDAP_DN_SPECIAL_CHARS_QUOTED_ALPHA_REGEX] = $alpharegex;
408
409 return $specialchars;
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410}
411
412/**
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413 * Quote control characters in AttributeValue parts of a RelativeDistinguishedName
414 * used in LDAP distinguished names - See RFC 4514/2253
5704585c 415 *
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416 * @param string the AttributeValue to quote
417 * @return string the AttributeValue quoted
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418 */
419function ldap_addslashes($text) {
420 $special_dn_chars = ldap_get_dn_special_chars();
421
527464a6 422 // Use the preferred/universal quotation method: ESC HEX HEX
cc220325 423 // (i.e., the 'numerically' quoted characters)
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424 $text = str_replace ($special_dn_chars[LDAP_DN_SPECIAL_CHARS],
425 $special_dn_chars[LDAP_DN_SPECIAL_CHARS_QUOTED_NUM],
426 $text);
427 return $text;
428}
429
430/**
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431 * Unquote control characters in AttributeValue parts of a RelativeDistinguishedName
432 * used in LDAP distinguished names - See RFC 4514/2253
5704585c 433 *
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434 * @param string the AttributeValue quoted
435 * @return string the AttributeValue unquoted
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436 */
437function ldap_stripslashes($text) {
cc220325 438 $specialchars = ldap_get_dn_special_chars();
5704585c 439
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440 // We can't unquote in two steps, as we end up unquoting too much in certain cases. So
441 // we need to build a regexp containing both the 'numerically' and 'alphabetically'
442 // quoted characters. We don't use LDAP_DN_SPECIAL_CHARS_QUOTED_NUM because the
443 // standard allows us to quote any character with this encoding, not just the special
5704585c 444 // ones.
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445 // @TODO: This still misses some special (and rarely used) cases, but we need
446 // a full state machine to handle them.
447 $quoted = '/(\\\\[0-9A-Fa-f]{2}|' . $specialchars[LDAP_DN_SPECIAL_CHARS_QUOTED_ALPHA_REGEX] . ')/';
448 $text = preg_replace_callback($quoted,
449 function ($match) use ($specialchars) {
450 if (ctype_xdigit(ltrim($match[1], '\\'))) {
451 return chr(hexdec($match[1]));
452 } else {
453 return str_replace($specialchars[LDAP_DN_SPECIAL_CHARS_QUOTED_ALPHA],
454 $specialchars[LDAP_DN_SPECIAL_CHARS],
455 $match[1]);
456 }
457 },
458 $text);
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459
460 return $text;
461}
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462
463
464/**
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465 * Check if we can use paged results (see RFC 2696). We need to use
466 * LDAP version 3 (or later), otherwise the server cannot use them. If
467 * we also pass in a valid LDAP connection handle, we also check
468 * whether the server actually supports them.
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469 *
470 * @param ldapversion integer The LDAP protocol version we use.
e47863e8 471 * @param ldapconnection resource An existing LDAP connection (optional).
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472 *
473 * @return boolean true is paged results can be used, false otherwise.
474 */
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475function ldap_paged_results_supported($ldapversion, $ldapconnection = null) {
476 if ((int)$ldapversion < 3) {
477 // Minimun required version: LDAP v3.
478 return false;
479 }
480
481 if ($ldapconnection === null) {
482 // Can't verify it, so assume it isn't supported.
483 return false;
484 }
485
486 // Connect to the rootDSE and get the supported controls.
487 $sr = ldap_read($ldapconnection, ROOTDSE, '(objectClass=*)', array('supportedControl'));
488 if (!$sr) {
489 return false;
490 }
491
492 $entries = ldap_get_entries_moodle($ldapconnection, $sr);
493 if (empty($entries)) {
494 return false;
495 }
67bebb69 496 $info = $entries[0];
e47863e8 497 if (isset($info['supportedcontrol']) && in_array(LDAP_PAGED_RESULTS_CONTROL, $info['supportedcontrol'])) {
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498 return true;
499 }
500
501 return false;
502}