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/lib/plugins/authldap/ -> auth.php (source)

   1  <?php
   2  use dokuwiki\Utf8\Sort;
   3  
   4  /**
   5   * LDAP authentication backend
   6   *
   7   * @license   GPL 2 (http://www.gnu.org/licenses/gpl.html)
   8   * @author    Andreas Gohr <andi@splitbrain.org>
   9   * @author    Chris Smith <chris@jalakaic.co.uk>
  10   * @author    Jan Schumann <js@schumann-it.com>
  11   */
  12  class auth_plugin_authldap extends DokuWiki_Auth_Plugin
  13  {
  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      {
  31          parent::__construct();
  32  
  33          // ldap extension is needed
  34          if (!function_exists('ldap_connect')) {
  35              $this->debug("LDAP err: PHP LDAP extension not found.", -1, __LINE__, __FILE__);
  36              $this->success = false;
  37              return;
  38          }
  39  
  40          // Add the capabilities to change the password
  41          $this->cando['modPass'] = $this->getConf('modPass');
  42      }
  43  
  44      /**
  45       * Check user+password
  46       *
  47       * Checks if the given user exists and the given
  48       * plaintext password is correct by trying to bind
  49       * to the LDAP server
  50       *
  51       * @param string $user
  52       * @param string $pass
  53       * @return  bool
  54       * @author  Andreas Gohr <andi@splitbrain.org>
  55       */
  56      public function checkPass($user, $pass)
  57      {
  58          // reject empty password
  59          if (empty($pass)) return false;
  60          if (!$this->openLDAP()) return false;
  61  
  62          // indirect user bind
  63          if ($this->getConf('binddn') && $this->getConf('bindpw')) {
  64              // use superuser credentials
  65              if (!@ldap_bind($this->con, $this->getConf('binddn'), conf_decodeString($this->getConf('bindpw')))) {
  66                  $this->debug('LDAP bind as superuser: ' . hsc(ldap_error($this->con)), 0, __LINE__, __FILE__);
  67                  return false;
  68              }
  69              $this->bound = 2;
  70          } elseif ($this->getConf('binddn') &&
  71              $this->getConf('usertree') &&
  72              $this->getConf('userfilter')
  73          ) {
  74              // special bind string
  75              $dn = $this->makeFilter(
  76                  $this->getConf('binddn'),
  77                  array('user' => $user, 'server' => $this->getConf('server'))
  78              );
  79          } elseif (strpos($this->getConf('usertree'), '%{user}')) {
  80              // direct user bind
  81              $dn = $this->makeFilter(
  82                  $this->getConf('usertree'),
  83                  array('user' => $user, 'server' => $this->getConf('server'))
  84              );
  85          } else {
  86              // Anonymous bind
  87              if (!@ldap_bind($this->con)) {
  88                  msg("LDAP: can not bind anonymously", -1);
  89                  $this->debug('LDAP anonymous bind: ' . hsc(ldap_error($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                  $this->debug('LDAP user dn bind: ' . hsc(ldap_error($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 = $this->fetchUserData($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                  $this->debug('LDAP user bind: ' . hsc(ldap_error($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       * @param string $user
 142       * @param bool $requireGroups (optional) - ignored, groups are always supplied by this plugin
 143       * @return  array containing user data or false
 144       * @author  <evaldas.auryla@pheur.org>
 145       * @author  Stephane Chazelas <stephane.chazelas@emerson.com>
 146       * @author  Steffen Schoch <schoch@dsb.net>
 147       *
 148       * @author  Andreas Gohr <andi@splitbrain.org>
 149       * @author  Trouble
 150       * @author  Dan Allen <dan.j.allen@gmail.com>
 151       */
 152      public function getUserData($user, $requireGroups = true)
 153      {
 154          return $this->fetchUserData($user);
 155      }
 156  
 157      /**
 158       * @param string $user
 159       * @param bool $inbind authldap specific, true if in bind phase
 160       * @return  array containing user data or false
 161       */
 162      protected function fetchUserData($user, $inbind = false)
 163      {
 164          global $conf;
 165          if (!$this->openLDAP()) return array();
 166  
 167          // force superuser bind if wanted and not bound as superuser yet
 168          if ($this->getConf('binddn') && $this->getConf('bindpw') && $this->bound < 2) {
 169              // use superuser credentials
 170              if (!@ldap_bind($this->con, $this->getConf('binddn'), conf_decodeString($this->getConf('bindpw')))) {
 171                  $this->debug('LDAP bind as superuser: ' . hsc(ldap_error($this->con)), 0, __LINE__, __FILE__);
 172                  return array();
 173              }
 174              $this->bound = 2;
 175          } elseif ($this->bound == 0 && !$inbind) {
 176              // in some cases getUserData is called outside the authentication workflow
 177              // eg. for sending email notification on subscribed pages. This data might not
 178              // be accessible anonymously, so we try to rebind the current user here
 179              list($loginuser, $loginsticky, $loginpass) = auth_getCookie();
 180              if ($loginuser && $loginpass) {
 181                  $loginpass = auth_decrypt($loginpass, auth_cookiesalt(!$loginsticky, true));
 182                  $this->checkPass($loginuser, $loginpass);
 183              }
 184          }
 185  
 186          $info = array();
 187          $info['user'] = $user;
 188          $this->debug('LDAP user to find: ' . hsc($info['user']), 0, __LINE__, __FILE__);
 189  
 190          $info['server'] = $this->getConf('server');
 191          $this->debug('LDAP Server: ' . hsc($info['server']), 0, __LINE__, __FILE__);
 192  
 193          //get info for given user
 194          $base = $this->makeFilter($this->getConf('usertree'), $info);
 195          if ($this->getConf('userfilter')) {
 196              $filter = $this->makeFilter($this->getConf('userfilter'), $info);
 197          } else {
 198              $filter = "(ObjectClass=*)";
 199          }
 200  
 201          $this->debug('LDAP Filter: ' . hsc($filter), 0, __LINE__, __FILE__);
 202  
 203          $this->debug('LDAP user search: ' . hsc(ldap_error($this->con)), 0, __LINE__, __FILE__);
 204          $this->debug('LDAP search at: ' . hsc($base . ' ' . $filter), 0, __LINE__, __FILE__);
 205          $sr = $this->ldapSearch($this->con, $base, $filter, $this->getConf('userscope'), $this->getConf('attributes'));
 206  
 207  
 208          $result = @ldap_get_entries($this->con, $sr);
 209  
 210          // if result is not an array
 211          if (!is_array($result)) {
 212              // no objects found
 213              $this->debug('LDAP search returned non-array result: ' . hsc(print($result)), -1, __LINE__, __FILE__);
 214              return array();
 215          }
 216  
 217          // Don't accept more or less than one response
 218          if ($result['count'] != 1) {
 219              $this->debug(
 220                  'LDAP search returned ' . hsc($result['count']) . ' results while it should return 1!',
 221                  -1,
 222                  __LINE__,
 223                  __FILE__
 224              );
 225              //for($i = 0; $i < $result["count"]; $i++) {
 226              //$this->_debug('result: '.hsc(print_r($result[$i])), 0, __LINE__, __FILE__);
 227              //}
 228              return array();
 229          }
 230  
 231          $this->debug('LDAP search found single result !', 0, __LINE__, __FILE__);
 232  
 233          $user_result = $result[0];
 234          ldap_free_result($sr);
 235  
 236          // general user info
 237          $info['dn'] = $user_result['dn'];
 238          $info['gid'] = $user_result['gidnumber'][0];
 239          $info['mail'] = $user_result['mail'][0];
 240          $info['name'] = $user_result['cn'][0];
 241          $info['grps'] = array();
 242  
 243          // overwrite if other attribs are specified.
 244          if (is_array($this->getConf('mapping'))) {
 245              foreach ($this->getConf('mapping') as $localkey => $key) {
 246                  if (is_array($key)) {
 247                      // use regexp to clean up user_result
 248                      // $key = array($key=>$regexp), only handles the first key-value
 249                      $regexp = current($key);
 250                      $key = key($key);
 251                      if ($user_result[$key]) foreach ($user_result[$key] as $grpkey => $grp) {
 252                          if ($grpkey !== 'count' && preg_match($regexp, $grp, $match)) {
 253                              if ($localkey == 'grps') {
 254                                  $info[$localkey][] = $match[1];
 255                              } else {
 256                                  $info[$localkey] = $match[1];
 257                              }
 258                          }
 259                      }
 260                  } else {
 261                      $info[$localkey] = $user_result[$key][0];
 262                  }
 263              }
 264          }
 265          $user_result = array_merge($info, $user_result);
 266  
 267          //get groups for given user if grouptree is given
 268          if ($this->getConf('grouptree') || $this->getConf('groupfilter')) {
 269              $base = $this->makeFilter($this->getConf('grouptree'), $user_result);
 270              $filter = $this->makeFilter($this->getConf('groupfilter'), $user_result);
 271              $sr = $this->ldapSearch(
 272                  $this->con,
 273                  $base,
 274                  $filter,
 275                  $this->getConf('groupscope'),
 276                  array($this->getConf('groupkey'))
 277              );
 278              $this->debug('LDAP group search: ' . hsc(ldap_error($this->con)), 0, __LINE__, __FILE__);
 279              $this->debug('LDAP search at: ' . hsc($base . ' ' . $filter), 0, __LINE__, __FILE__);
 280  
 281              if (!$sr) {
 282                  msg("LDAP: Reading group memberships failed", -1);
 283                  return array();
 284              }
 285              $result = ldap_get_entries($this->con, $sr);
 286              ldap_free_result($sr);
 287  
 288              if (is_array($result)) foreach ($result as $grp) {
 289                  if (!empty($grp[$this->getConf('groupkey')])) {
 290                      $group = $grp[$this->getConf('groupkey')];
 291                      if (is_array($group)) {
 292                          $group = $group[0];
 293                      } else {
 294                          $this->debug('groupkey did not return a detailled result', 0, __LINE__, __FILE__);
 295                      }
 296                      if ($group === '') continue;
 297  
 298                      $this->debug('LDAP usergroup: ' . hsc($group), 0, __LINE__, __FILE__);
 299                      $info['grps'][] = $group;
 300                  }
 301              }
 302          }
 303  
 304          // always add the default group to the list of groups
 305          if (!$info['grps'] or !in_array($conf['defaultgroup'], $info['grps'])) {
 306              $info['grps'][] = $conf['defaultgroup'];
 307          }
 308          return $info;
 309      }
 310  
 311      /**
 312       * Definition of the function modifyUser in order to modify the password
 313       *
 314       * @param string $user nick of the user to be changed
 315       * @param array $changes array of field/value pairs to be changed (password will be clear text)
 316       * @return  bool   true on success, false on error
 317       */
 318      public function modifyUser($user, $changes)
 319      {
 320  
 321          // open the connection to the ldap
 322          if (!$this->openLDAP()) {
 323              $this->debug('LDAP cannot connect: ' . hsc(ldap_error($this->con)), 0, __LINE__, __FILE__);
 324              return false;
 325          }
 326  
 327          // find the information about the user, in particular the "dn"
 328          $info = $this->getUserData($user, true);
 329          if (empty($info['dn'])) {
 330              $this->debug('LDAP cannot find your user dn', 0, __LINE__, __FILE__);
 331              return false;
 332          }
 333          $dn = $info['dn'];
 334  
 335          // find the old password of the user
 336          list($loginuser, $loginsticky, $loginpass) = auth_getCookie();
 337          if ($loginuser !== null) { // the user is currently logged in
 338              $secret = auth_cookiesalt(!$loginsticky, true);
 339              $pass = auth_decrypt($loginpass, $secret);
 340  
 341              // bind with the ldap
 342              if (!@ldap_bind($this->con, $dn, $pass)) {
 343                  $this->debug(
 344                      'LDAP user bind failed: ' . hsc($dn) . ': ' . hsc(ldap_error($this->con)),
 345                      0,
 346                      __LINE__,
 347                      __FILE__
 348                  );
 349                  return false;
 350              }
 351          } elseif ($this->getConf('binddn') && $this->getConf('bindpw')) {
 352              // we are changing the password on behalf of the user (eg: forgotten password)
 353              // bind with the superuser ldap
 354              if (!@ldap_bind($this->con, $this->getConf('binddn'), conf_decodeString($this->getConf('bindpw')))) {
 355                  $this->debug('LDAP bind as superuser: ' . hsc(ldap_error($this->con)), 0, __LINE__, __FILE__);
 356                  return false;
 357              }
 358          } else {
 359              return false; // no otherway
 360          }
 361  
 362          // Generate the salted hashed password for LDAP
 363          $phash = new \dokuwiki\PassHash();
 364          $hash = $phash->hash_ssha($changes['pass']);
 365  
 366          // change the password
 367          if (!@ldap_mod_replace($this->con, $dn, array('userpassword' => $hash))) {
 368              $this->debug(
 369                  'LDAP mod replace failed: ' . hsc($dn) . ': ' . hsc(ldap_error($this->con)),
 370                  0,
 371                  __LINE__,
 372                  __FILE__
 373              );
 374              return false;
 375          }
 376  
 377          return true;
 378      }
 379  
 380      /**
 381       * Most values in LDAP are case-insensitive
 382       *
 383       * @return bool
 384       */
 385      public function isCaseSensitive()
 386      {
 387          return false;
 388      }
 389  
 390      /**
 391       * Bulk retrieval of user data
 392       *
 393       * @param int $start index of first user to be returned
 394       * @param int $limit max number of users to be returned
 395       * @param array $filter array of field/pattern pairs, null for no filter
 396       * @return  array of userinfo (refer getUserData for internal userinfo details)
 397       * @author  Dominik Eckelmann <dokuwiki@cosmocode.de>
 398       */
 399      public function retrieveUsers($start = 0, $limit = 0, $filter = array())
 400      {
 401          if (!$this->openLDAP()) return array();
 402  
 403          if (is_null($this->users)) {
 404              // Perform the search and grab all their details
 405              if ($this->getConf('userfilter')) {
 406                  $all_filter = str_replace('%{user}', '*', $this->getConf('userfilter'));
 407              } else {
 408                  $all_filter = "(ObjectClass=*)";
 409              }
 410              $sr = ldap_search($this->con, $this->getConf('usertree'), $all_filter);
 411              $entries = ldap_get_entries($this->con, $sr);
 412              $users_array = array();
 413              $userkey = $this->getConf('userkey');
 414              for ($i = 0; $i < $entries["count"]; $i++) {
 415                  array_push($users_array, $entries[$i][$userkey][0]);
 416              }
 417              Sort::asort($users_array);
 418              $result = $users_array;
 419              if (!$result) return array();
 420              $this->users = array_fill_keys($result, false);
 421          }
 422          $i = 0;
 423          $count = 0;
 424          $this->constructPattern($filter);
 425          $result = array();
 426  
 427          foreach ($this->users as $user => &$info) {
 428              if ($i++ < $start) {
 429                  continue;
 430              }
 431              if ($info === false) {
 432                  $info = $this->getUserData($user);
 433              }
 434              if ($this->filter($user, $info)) {
 435                  $result[$user] = $info;
 436                  if (($limit > 0) && (++$count >= $limit)) break;
 437              }
 438          }
 439          return $result;
 440      }
 441  
 442      /**
 443       * Make LDAP filter strings.
 444       *
 445       * Used by auth_getUserData to make the filter
 446       * strings for grouptree and groupfilter
 447       *
 448       * @param string $filter ldap search filter with placeholders
 449       * @param array $placeholders placeholders to fill in
 450       * @return  string
 451       * @author  Troels Liebe Bentsen <tlb@rapanden.dk>
 452       */
 453      protected function makeFilter($filter, $placeholders)
 454      {
 455          preg_match_all("/%{([^}]+)/", $filter, $matches, PREG_PATTERN_ORDER);
 456          //replace each match
 457          foreach ($matches[1] as $match) {
 458              //take first element if array
 459              if (is_array($placeholders[$match])) {
 460                  $value = $placeholders[$match][0];
 461              } else {
 462                  $value = $placeholders[$match];
 463              }
 464              $value = $this->filterEscape($value);
 465              $filter = str_replace('%{' . $match . '}', $value, $filter);
 466          }
 467          return $filter;
 468      }
 469  
 470      /**
 471       * return true if $user + $info match $filter criteria, false otherwise
 472       *
 473       * @param string $user the user's login name
 474       * @param array $info the user's userinfo array
 475       * @return bool
 476       * @author Chris Smith <chris@jalakai.co.uk>
 477       *
 478       */
 479      protected function filter($user, $info)
 480      {
 481          foreach ($this->pattern as $item => $pattern) {
 482              if ($item == 'user') {
 483                  if (!preg_match($pattern, $user)) return false;
 484              } elseif ($item == 'grps') {
 485                  if (!count(preg_grep($pattern, $info['grps']))) return false;
 486              } else {
 487                  if (!preg_match($pattern, $info[$item])) return false;
 488              }
 489          }
 490          return true;
 491      }
 492  
 493      /**
 494       * Set the filter pattern
 495       *
 496       * @param $filter
 497       * @return void
 498       * @author Chris Smith <chris@jalakai.co.uk>
 499       *
 500       */
 501      protected function constructPattern($filter)
 502      {
 503          $this->pattern = array();
 504          foreach ($filter as $item => $pattern) {
 505              $this->pattern[$item] = '/' . str_replace('/', '\/', $pattern) . '/i'; // allow regex characters
 506          }
 507      }
 508  
 509      /**
 510       * Escape a string to be used in a LDAP filter
 511       *
 512       * Ported from Perl's Net::LDAP::Util escape_filter_value
 513       *
 514       * @param string $string
 515       * @return string
 516       * @author Andreas Gohr
 517       */
 518      protected function filterEscape($string)
 519      {
 520          // see https://github.com/adldap/adLDAP/issues/22
 521          return preg_replace_callback(
 522              '/([\x00-\x1F\*\(\)\\\\])/',
 523              function ($matches) {
 524                  return "\\" . join("", unpack("H2", $matches[1]));
 525              },
 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)) $attributes = array();
 654  
 655          if ($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  }