functions/abook_ldap_server.php

   1 <?php
   2 /**
   3  * abook_ldap_server.php
   4  *
   5  * Copyright (c) 1999-2005 The SquirrelMail Project Team
   6  * Licensed under the GNU GPL. For full terms see the file COPYING.
   7  *
   8  * Address book backend for LDAP server
   9  *
  10  * LDAP filtering code by Tim Bell
  11  *   <bhat at users.sourceforge.net> (#539534)
  12  * ADS limit_scope code by Michael Brown
  13  *   <mcb30 at users.sourceforge.net> (#1035454)
  14  * StartTLS code by John Lane
  15  *   <starfry at users.sourceforge.net> (#1197703)
  16  *
  17  * @version $Id$
  18  * @package squirrelmail
  19  * @subpackage addressbook
  20  */
  21
  22 /**
  23  * Address book backend for LDAP server
  24  *
  25  * An array with the following elements must be passed to
  26  * the class constructor (elements marked ? are optional)
  27  *
  28  * Main settings:
  29  * <pre>
  30  *    host      => LDAP server hostname/IP-address
  31  *    base      => LDAP server root (base dn). Empty string allowed.
  32  *  ? port      => LDAP server TCP port number (default: 389)
  33  *  ? charset   => LDAP server charset (default: utf-8)
  34  *  ? name      => Name for LDAP server (default "LDAP: hostname")
  35  *                 Used to tag the result data
  36  *  ? maxrows   => Maximum # of rows in search result
  37  *  ? timeout   => Timeout for LDAP operations (in seconds, default: 30)
  38  *                 Might not work for all LDAP libraries or servers.
  39  *  ? binddn    => LDAP Bind DN.
  40  *  ? bindpw    => LDAP Bind Password.
  41  *  ? protocol  => LDAP Bind protocol.
  42  * </pre>
  43  * Advanced settings:
  44  * <pre>
  45  *  ? filter    => Filter expression to limit ldap searches
  46  *  ? limit_scope => Limits scope to base DN (Specific to Win2k3 ADS).
  47  *  ? listing   => Controls listing of LDAP directory.
  48  *  ? search_tree => Controls subtree or one level search.
  49  *  ? starttls  => Controls use of StartTLS on LDAP connections
  50  * </pre>
  51  * NOTE. This class should not be used directly. Use the
  52  *       "AddressBook" class instead.
  53  * @package squirrelmail
  54  * @subpackage addressbook
  55  */
  56 class abook_ldap_server extends addressbook_backend {
  57     /**
  58      * @var string backend type
  59      */
  60     var $btype = 'remote';
  61     /**
  62      * @var string backend name
  63      */
  64     var $bname = 'ldap_server';
  65
  66     /* Parameters changed by class */
  67     /**
  68      * @var string displayed name
  69      */
  70     var $sname   = 'LDAP';       /* Service name */
  71     /**
  72      * @var string LDAP server name or address or url
  73      */
  74     var $server  = '';
  75     /**
  76      * @var integer LDAP server port
  77      */
  78     var $port    = 389;
  79     /**
  80      * @var string LDAP base DN
  81      */
  82     var $basedn  = '';
  83     /**
  84      * @var string charset used for entries in LDAP server
  85      */
  86     var $charset = 'utf-8';
  87     /**
  88      * @var object PHP LDAP link ID
  89      */
  90     var $linkid  = false;
  91     /**
  92      * @var bool True if LDAP server is bound
  93      */
  94     var $bound   = false;
  95     /**
  96      * @var integer max rows in result
  97      */
  98     var $maxrows = 250;
  99     /**
 100      * @var string ldap filter
 101      * @since 1.5.1
 102      */
 103     var $filter = '';
 104     /**
 105      * @var integer timeout of LDAP operations (in seconds)
 106      */
 107     var $timeout = 30;
 108     /**
 109      * @var string DN to bind to (non-anonymous bind)
 110      * @since 1.5.0 and 1.4.3
 111      */
 112     var $binddn = '';
 113     /**
 114      * @var string  password to bind with (non-anonymous bind)
 115      * @since 1.5.0 and 1.4.3
 116      */
 117     var $bindpw = '';
 118     /**
 119      * @var integer protocol used to connect to ldap server
 120      * @since 1.5.0 and 1.4.3
 121      */
 122     var $protocol = '';
 123     /**
 124      * @var boolean limits scope to base dn
 125      * @since 1.5.1
 126      */
 127     var $limit_scope = false;
 128     /**
 129      * @var boolean controls listing of directory
 130      * @since 1.5.1
 131      */
 132     var $listing = false;
 133     /**
 134      * @var boolean controls ldap search type.
 135      * only first level entries are displayed if set to false
 136      * @since 1.5.1
 137      */
 138     var $search_tree = true;
 139     /**
 140      * @var boolean controls use of StartTLS on ldap
 141      * connections. Requires php 4.2+ and protocol >= 3
 142      * @since 1.5.1
 143      */
 144     var $starttls = false;
 145
 146     /**
 147      * Constructor. Connects to database
 148      * @param array connection options
 149      */
 150     function abook_ldap_server($param) {
 151         if(!function_exists('ldap_connect')) {
 152             $this->set_error(_("PHP install does not have LDAP support."));
 153             return;
 154         }
 155         if(is_array($param)) {
 156             $this->server = $param['host'];
 157             $this->basedn = $param['base'];
 158
 159             if(!empty($param['port']))
 160                 $this->port = $param['port'];
 161
 162             if(!empty($param['charset']))
 163                 $this->charset = strtolower($param['charset']);
 164
 165             if(isset($param['maxrows']))
 166                 $this->maxrows = $param['maxrows'];
 167
 168             if(isset($param['timeout']))
 169                 $this->timeout = $param['timeout'];
 170
 171             if(isset($param['binddn']))
 172                 $this->binddn = $param['binddn'];
 173
 174             if(isset($param['bindpw']))
 175                 $this->bindpw = $param['bindpw'];
 176
 177             if(isset($param['protocol']))
 178                 $this->protocol = (int) $param['protocol'];
 179
 180             if(isset($param['filter']))
 181                 $this->filter = trim($param['filter']);
 182
 183             if(isset($param['limit_scope']))
 184                 $this->limit_scope = (bool) $param['limit_scope'];
 185
 186             if(isset($param['listing']))
 187                 $this->listing = (bool) $param['listing'];
 188
 189             if(isset($param['search_tree']))
 190                 $this->search_tree = (bool) $param['search_tree'];
 191
 192             if(isset($param['starttls']))
 193                 $this->starttls = (bool) $param['starttls'];
 194
 195             if(empty($param['name'])) {
 196                 $this->sname = 'LDAP: ' . $param['host'];
 197             } else {
 198                 $this->sname = $param['name'];
 199             }
 200
 201             /*
 202              * don't open LDAP server on addressbook_init(),
 203              * open ldap connection only on search. Speeds up
 204              * addressbook_init() call.
 205              */
 206             // $this->open(true);
 207         } else {
 208             $this->set_error('Invalid argument to constructor');
 209         }
 210     }
 211
 212
 213     /**
 214      * Open the LDAP server.
 215      * @param bool $new is it a new connection
 216      * @return bool
 217      */
 218     function open($new = false) {
 219         $this->error = '';
 220
 221         /* Connection is already open */
 222         if($this->linkid != false && !$new) {
 223             return true;
 224         }
 225
 226         $this->linkid = @ldap_connect($this->server, $this->port);
 227         /**
 228          * check if connection was successful
 229          * It does not work with OpenLDAP 2.x libraries. Connect error will be
 230          * displayed only on ldap command that tries to make connection
 231          * (ldap_start_tls or ldap_bind).
 232          */
 233         if(!$this->linkid) {
 234             return $this->set_error($this->ldap_error('ldap_connect failed'));
 235         }
 236
 237         if(!empty($this->protocol)) {
 238             // make sure that ldap_set_option() is available before using it
 239             if(! function_exists('ldap_set_option') ||
 240                !@ldap_set_option($this->linkid, LDAP_OPT_PROTOCOL_VERSION, $this->protocol)) {
 241                 return $this->set_error('unable to set ldap protocol number');
 242             }
 243         }
 244
 245         /**
 246          * http://www.php.net/ldap-start-tls
 247          * Check if v3 or newer protocol is used,
 248          * check if ldap_start_tls function is available.
 249          * Silently ignore setting, if requirements are not satisfied
 250          */
 251         if($this->starttls &&
 252            !empty($this->protocol) && $this->protocol >= 3 &&
 253            function_exists('ldap_start_tls') ) {
 254             // make sure that $this->host is not ldaps:// URL.
 255             if (preg_match("/^ldaps:\/\/.+/i",$this->server)) {
 256                 return $this->set_error("you can't enable starttls on ldaps connection.");
 257             }
 258             // TODO: starttls and ldapi:// tests are needed
 259
 260             // try starting tls
 261             if (! @ldap_start_tls($this->linkid)) {
 262                 // set error if call fails
 263                 return $this->set_error($this->ldap_error('ldap_start_tls failed'));
 264             }
 265         }
 266
 267         if(!empty($this->limit_scope) && $this->limit_scope) {
 268             if(empty($this->protocol) || intval($this->protocol) < 3) {
 269                 return $this->set_error('limit_scope requires protocol >= 3');
 270             }
 271             // See http://msdn.microsoft.com/library/en-us/ldap/ldap/ldap_server_domain_scope_oid.asp
 272             $ctrl = array ( "oid" => "1.2.840.113556.1.4.1339", "iscritical" => TRUE );
 273             /*
 274              * Option is set only during connection.
 275              * It does not cause immediate errors with OpenLDAP 2.x libraries.
 276              */
 277             if(! function_exists('ldap_set_option') ||
 278                !@ldap_set_option($this->linkid, LDAP_OPT_SERVER_CONTROLS, array($ctrl))) {
 279                 return $this->set_error($this->ldap_error('limit domain scope failed'));
 280             }
 281         }
 282
 283         // authenticated bind
 284         if(!empty($this->binddn)) {
 285             if(!@ldap_bind($this->linkid, $this->binddn, $this->bindpw)) {
 286                 return $this->set_error($this->ldap_error('authenticated ldap_bind failed'));
 287             }
 288         } else {
 289             // anonymous bind
 290             if(!@ldap_bind($this->linkid)) {
 291                 return $this->set_error($this->ldap_error('anonymous ldap_bind failed'));
 292             }
 293         }
 294
 295         $this->bound = true;
 296
 297         return true;
 298     }
 299
 300     /**
 301      * Encode string to the charset used by this LDAP server
 302      * @param string string that has to be encoded
 303      * @return string encoded string
 304      */
 305     function charset_encode($str) {
 306         global $default_charset;
 307         if($this->charset != $default_charset) {
 308             return charset_convert($default_charset,$str,$this->charset,false);
 309         } else {
 310             return $str;
 311         }
 312     }
 313
 314     /**
 315      * Decode from charset used by this LDAP server to charset used by translation
 316      *
 317      * Uses SquirrelMail charset_decode functions
 318      * @param string string that has to be decoded
 319      * @return string decoded string
 320      */
 321     function charset_decode($str) {
 322         global $default_charset;
 323         if ($this->charset != $default_charset) {
 324             return charset_convert($this->charset,$str,$default_charset,false);
 325         } else {
 326             return $str;
 327         }
 328     }
 329
 330     /**
 331      * Sanitizes ldap search strings.
 332      * See rfc2254
 333      * @link http://www.faqs.org/rfcs/rfc2254.html
 334      * @since 1.5.1 and 1.4.5
 335      * @param string $string
 336      * @return string sanitized string
 337      */
 338     function ldapspecialchars($string) {
 339         $sanitized=array('\\' => '\5c',
 340                          '*' => '\2a',
 341                          '(' => '\28',
 342                          ')' => '\29',
 343                          "\x00" => '\00');
 344
 345         return str_replace(array_keys($sanitized),array_values($sanitized),$string);
 346     }
 347
 348     /**
 349      * Search LDAP server.
 350      *
 351      * Warning: You must make sure that ldap query is correctly formated and
 352      * sanitize use of special ldap keywords.
 353      * @param string $expression ldap query
 354      * @return array search results (false on error)
 355      * @since 1.5.1
 356      */
 357     function ldap_search($expression) {
 358         /* Make sure connection is there */
 359         if(!$this->open()) {
 360             return false;
 361         }
 362
 363         if ($this->search_tree) {
 364             // ldap_search - search subtree
 365             $sret = @ldap_search($this->linkid, $this->basedn, $expression,
 366                 array('dn', 'o', 'ou', 'sn', 'givenname', 'cn', 'mail'),
 367                 0, $this->maxrows, $this->timeout);
 368         } else {
 369             // ldap_list - search one level
 370             $sret = @ldap_list($this->linkid, $this->basedn, $expression,
 371                 array('dn', 'o', 'ou', 'sn', 'givenname', 'cn', 'mail'),
 372                 0, $this->maxrows, $this->timeout);
 373         }
 374
 375         /* Return error if search failed */
 376         if(!$sret) {
 377             return $this->set_error($this->ldap_error('ldap_search failed'));
 378         }
 379
 380         if(@ldap_count_entries($this->linkid, $sret) <= 0) {
 381             return array();
 382         }
 383
 384         /* Get results */
 385         $ret = array();
 386         $returned_rows = 0;
 387         $res = @ldap_get_entries($this->linkid, $sret);
 388         for($i = 0 ; $i < $res['count'] ; $i++) {
 389             $row = $res[$i];
 390
 391             /* Extract data common for all e-mail addresses
 392              * of an object. Use only the first name */
 393             $nickname = $this->charset_decode($row['dn']);
 394
 395             /**
 396              * calculate length of basedn and remove it from nickname
 397              * ignore whitespaces between RDNs
 398              * Nicknames are shorter and still unique
 399              */
 400             $basedn_len=strlen(preg_replace('/,\s*/',',',trim($this->basedn)));
 401             $nickname=substr(preg_replace('/,\s*/',',',$nickname),0,(-1 - $basedn_len));
 402
 403             $fullname = $this->charset_decode($row['cn'][0]);
 404
 405             if(!empty($row['ou'][0])) {
 406                 $label = $this->charset_decode($row['ou'][0]);
 407             }
 408             else if(!empty($row['o'][0])) {
 409                 $label = $this->charset_decode($row['o'][0]);
 410             } else {
 411                 $label = '';
 412             }
 413
 414             if(empty($row['givenname'][0])) {
 415                 $firstname = '';
 416             } else {
 417                 $firstname = $this->charset_decode($row['givenname'][0]);
 418             }
 419
 420             if(empty($row['sn'][0])) {
 421                 $surname = '';
 422             } else {
 423                 $surname = $this->charset_decode($row['sn'][0]);
 424             }
 425
 426             /* Add one row to result for each e-mail address */
 427             if(isset($row['mail']['count'])) {
 428                 for($j = 0 ; $j < $row['mail']['count'] ; $j++) {
 429                     array_push($ret, array('nickname'  => $nickname,
 430                    'name'      => $fullname,
 431                    'firstname' => $firstname,
 432                    'lastname'  => $surname,
 433                    'email'     => $row['mail'][$j],
 434                    'label'     => $label,
 435                    'backend'   => $this->bnum,
 436                    'source'    => &$this->sname));
 437
 438                     // Limit number of hits
 439                     $returned_rows++;
 440                     if(($returned_rows >= $this->maxrows) &&
 441                        ($this->maxrows > 0) ) {
 442                         ldap_free_result($sret);
 443                         return $ret;
 444                     }
 445
 446                 } // for($j ...)
 447
 448             } // isset($row['mail']['count'])
 449
 450         }
 451
 452         ldap_free_result($sret);
 453         return $ret;
 454     }
 455
 456     /**
 457      * Get error from LDAP resource if possible
 458      *
 459      * Should get error from server using the ldap_errno() and ldap_err2str() functions
 460      * @param string $sError error message used when ldap error functions
 461      * and connection resource are unavailable
 462      * @return string error message
 463      * @since 1.5.1
 464      */
 465     function ldap_error($sError) {
 466         // it is possible that function_exists() tests are not needed
 467         if(function_exists('ldap_err2str') &&
 468            function_exists('ldap_errno') &&
 469            is_resource($this->linkid)) {
 470             return ldap_err2str(ldap_errno($this->linkid));
 471             // return ldap_error($this->linkid);
 472         } else {
 473             return $sError;
 474         }
 475     }
 476
 477     /* ========================== Public ======================== */
 478
 479     /**
 480      * Search the LDAP server
 481      * @param string $expr search expression
 482      * @return array search results
 483      */
 484     function search($expr) {
 485         /* To be replaced by advanded search expression parsing */
 486         if(is_array($expr)) return false;
 487
 488         // don't allow wide search when listing is disabled.
 489         if ($expr=='*' && ! $this->listing) {
 490             return array();
 491         } elseif ($expr=='*') {
 492             // allow use of wildcard when listing is enabled.
 493             $expression = '(cn=*)';
 494         } else {
 495             /* Convert search from user's charset to the one used in ldap */
 496             $expr = $this->charset_encode($expr);
 497
 498             /* Make sure that search does not contain ldap special chars */
 499             $expression = '(cn=*' . $this->ldapspecialchars($expr) . '*)';
 500
 501             /* Undo sanitizing of * symbol */
 502             $expression = str_replace('\2a','*',$expression);
 503             /* TODO: implement any single character (?) matching */
 504         }
 505
 506         /* Add search filtering */
 507         if ($this->filter!='')
 508             $expression = '(&' . $this->filter . $expression . ')';
 509
 510         /* Use internal search function and return search results */
 511         return $this->ldap_search($expression);
 512     }
 513
 514
 515     /**
 516      * List all entries present in LDAP server
 517      *
 518      * maxrows setting might limit list of returned entries.
 519      * Careful with this -- it could get quite large for big sites.
 520      * @return array all entries in ldap server
 521      */
 522      function list_addr() {
 523          if (! $this->listing)
 524              return array();
 525
 526          /* set wide search expression */
 527          $expression = '(cn=*)';
 528
 529          /* add filtering */
 530          if ($this->filter!='')
 531              $expression = '(&' . $this->filter . $expression .')';
 532
 533          /* use internal search function and return search results */
 534          return $this->ldap_search($expression);
 535      }
 536 }
 537 ?>