source: subversion/trunk/roundcubemail/program/include/rcube_ldap.php @ 4560

<?php
/*
 +-----------------------------------------------------------------------+
 | program/include/rcube_ldap.php                                        |
 |                                                                       |
 | This file is part of the Roundcube Webmail client                     |
 | Copyright (C) 2006-2011, The Roundcube Dev Team                       |
 | Licensed under the GNU GPL                                            |
 |                                                                       |
 | PURPOSE:                                                              |
 |   Interface to an LDAP address directory                              |
 |                                                                       |
 +-----------------------------------------------------------------------+
 | Author: Thomas Bruederli <roundcube@gmail.com>                        |
 |         Andreas Dick <andudi (at) gmx (dot) ch>                       |
 +-----------------------------------------------------------------------+

 $Id$

*/


/**
 * Model class to access an LDAP address directory
 *
 * @package Addressbook
 */
class rcube_ldap extends rcube_addressbook
{
    /** public properties */
    public $primary_key = 'ID';
    public $groups = false;
    public $readonly = true;
    public $ready = false;
    public $group_id = 0;
    public $list_page = 1;
    public $page_size = 10;
    public $coltypes = array();

    /** private properties */
    protected $conn;
    protected $prop = array();
    protected $fieldmap = array();

    protected $filter = '';
    protected $result = null;
    protected $ldap_result = null;
    protected $sort_col = '';
    protected $mail_domain = '';
    protected $debug = false;

    private $group_cache = array();
    private $group_members = array();


    /**
    * Object constructor
    *
    * @param array      LDAP connection properties
    * @param boolean    Enables debug mode
    * @param string     Current user mail domain name
    * @param integer User-ID
    */
    function __construct($p, $debug=false, $mail_domain=NULL)
    {
        $this->prop = $p;

        // check if groups are configured
        if (is_array($p['groups']))
            $this->groups = true;

        // fieldmap property is given
        if (is_array($p['fieldmap'])) {
            foreach ($p['fieldmap'] as $rf => $lf)
                $this->fieldmap[$rf] = $this->_attr_name(strtolower($lf));
        }
        else {
            // read deprecated *_field properties to remain backwards compatible
            foreach ($p as $prop => $value)
                if (preg_match('/^(.+)_field$/', $prop, $matches))
                    $this->fieldmap[$matches[1]] = $this->_attr_name(strtolower($value));
        }

        // use fieldmap to advertise supported coltypes to the application
        foreach ($this->fieldmap as $col => $lf) {
            list($col, $type) = explode(':', $col);
            if (!is_array($this->coltypes[$col])) {
                $subtypes = $type ? array($type) : null;
                $this->coltypes[$col] = array('limit' => 2, 'subtypes' => $subtypes);
            }
            elseif ($type) {
                $this->coltypes[$col]['subtypes'][] = $type;
                $this->coltypes[$col]['limit']++;
            }
            if ($type && !$this->fieldmap[$col])
                $this->fieldmap[$col] = $lf;
        }

        if ($this->fieldmap['street'] && $this->fieldmap['locality'])
            $this->coltypes['address'] = array('limit' => 1);
        else if ($this->coltypes['address'])
            $this->coltypes['address'] = array('type' => 'textarea', 'childs' => null, 'limit' => 1, 'size' => 40);

        // make sure 'required_fields' is an array
        if (!is_array($this->prop['required_fields']))
            $this->prop['required_fields'] = (array) $this->prop['required_fields'];

        foreach ($this->prop['required_fields'] as $key => $val)
            $this->prop['required_fields'][$key] = $this->_attr_name(strtolower($val));

        $this->sort_col = $p['sort'];
        $this->debug = $debug;
        $this->mail_domain = $mail_domain;

        $this->_connect();
    }


    /**
    * Establish a connection to the LDAP server
    */
    private function _connect()
    {
        global $RCMAIL;

        if (!function_exists('ldap_connect'))
            raise_error(array('code' => 100, 'type' => 'ldap',
            'file' => __FILE__, 'line' => __LINE__,
            'message' => "No ldap support in this installation of PHP"), true);

        if (is_resource($this->conn))
            return true;

        if (!is_array($this->prop['hosts']))
            $this->prop['hosts'] = array($this->prop['hosts']);

        if (empty($this->prop['ldap_version']))
            $this->prop['ldap_version'] = 3;

        foreach ($this->prop['hosts'] as $host)
        {
            $host = idn_to_ascii(rcube_parse_host($host));
            $this->_debug("C: Connect [$host".($this->prop['port'] ? ':'.$this->prop['port'] : '')."]");

            if ($lc = @ldap_connect($host, $this->prop['port']))
            {
                if ($this->prop['use_tls']===true)
                    if (!ldap_start_tls($lc))
                        continue;

                $this->_debug("S: OK");

                ldap_set_option($lc, LDAP_OPT_PROTOCOL_VERSION, $this->prop['ldap_version']);
                $this->prop['host'] = $host;
                $this->conn = $lc;
                break;
            }
            $this->_debug("S: NOT OK");
        }

        if (is_resource($this->conn))
        {
            $this->ready = true;

            $bind_pass = $this->prop['bind_pass'];
            $bind_user = $this->prop['bind_user'];
            $bind_dn   = $this->prop['bind_dn'];
            $base_dn   = $this->prop['base_dn'];

            // User specific access, generate the proper values to use.
            if ($this->prop['user_specific']) {
                // No password set, use the session password
                if (empty($bind_pass)) {
                    $bind_pass = $RCMAIL->decrypt($_SESSION['password']);
                }

                // Get the pieces needed for variable replacement.
                $fu = $RCMAIL->user->get_username();
                list($u, $d) = explode('@', $fu);
                $dc = 'dc='.strtr($d, array('.' => ',dc=')); // hierarchal domain string

                $replaces = array('%dc' => $dc, '%d' => $d, '%fu' => $fu, '%u' => $u);

                if ($this->prop['search_base_dn'] && $this->prop['search_filter']) {
                    // Search for the dn to use to authenticate
                    $this->prop['search_base_dn'] = strtr($this->prop['search_base_dn'], $replaces);
                    $this->prop['search_filter'] = strtr($this->prop['search_filter'], $replaces);

                    $this->_debug("S: searching with base {$this->prop['search_base_dn']} for {$this->prop['search_filter']}");

                    $res = ldap_search($this->conn, $this->prop['search_base_dn'], $this->prop['search_filter'], array('uid'));
                    if ($res && ($entry = ldap_first_entry($this->conn, $res))) {
                        $bind_dn = ldap_get_dn($this->conn, $entry);

                        $this->_debug("S: search returned dn: $bind_dn");

                        if ($bind_dn) {
                            $dn = ldap_explode_dn($bind_dn, 1);
                            $replaces['%dn'] = $dn[0];
                        }
                    }
                }
                // Replace the bind_dn and base_dn variables.
                $bind_dn   = strtr($bind_dn, $replaces);
                $base_dn   = strtr($base_dn, $replaces);

                if (empty($bind_user)) {
                    $bind_user = $u;
                }
            }

            if (!empty($bind_pass)) {
                if (!empty($bind_dn)) {
                    $this->ready = $this->_bind($bind_dn, $bind_pass);
                }
                else if (!empty($this->prop['auth_cid'])) {
                    $this->ready = $this->_sasl_bind($this->prop['auth_cid'], $bind_pass, $bind_user);
                }
                else {
                    $this->ready = $this->_sasl_bind($bind_user, $bind_pass);
                }
            }
        }
        else
            raise_error(array('code' => 100, 'type' => 'ldap',
                'file' => __FILE__, 'line' => __LINE__,
                'message' => "Could not connect to any LDAP server, last tried $host:{$this->prop[port]}"), true);

        // See if the directory is writeable.
        if ($this->prop['writable']) {
            $this->readonly = false;
        } // end if
    }


    /**
     * Bind connection with (SASL-) user and password
     *
     * @param string $authc Authentication user
     * @param string $pass  Bind password
     * @param string $authz Autorization user
     *
     * @return boolean True on success, False on error
     */
    private function _sasl_bind($authc, $pass, $authz=null)
    {
        if (!$this->conn) {
            return false;
        }

        if (!function_exists('ldap_sasl_bind')) {
            raise_error(array(
                'code' => 100, 'type' => 'ldap',
                'file' => __FILE__, 'line' => __LINE__,
                'message' => "Unable to bind: ldap_sasl_bind() not exists"),
            true, true);
        }

        if (!empty($authz)) {
            $authz = 'u:' . $authz;
        }

        if (!empty($this->prop['auth_method'])) {
            $method = $this->prop['auth_method'];
        }
        else {
            $method = 'DIGEST-MD5';
        }

        $this->_debug("C: Bind [mech: $method, authc: $authc, authz: $authz] [pass: $pass]");

        if (ldap_sasl_bind($this->conn, NULL, $pass, $method, NULL, $authc, $authz)) {
            $this->_debug("S: OK");
            return true;
        }

        $this->_debug("S: ".ldap_error($this->conn));

        raise_error(array(
            'code' => ldap_errno($this->conn), 'type' => 'ldap',
            'file' => __FILE__, 'line' => __LINE__,
            'message' => "Bind failed for authcid=$authc ".ldap_error($this->conn)),
            true);

        return false;
    }


    /**
    * Bind connection with DN and password
    *
    * @param string Bind DN
    * @param string Bind password
    * @return boolean True on success, False on error
    */
    private function _bind($dn, $pass)
    {
        if (!$this->conn) {
            return false;
        }

        $this->_debug("C: Bind [dn: $dn] [pass: $pass]");

        if (@ldap_bind($this->conn, $dn, $pass)) {
            $this->_debug("S: OK");
            return true;
        }

        $this->_debug("S: ".ldap_error($this->conn));

        $error =  array(
                'code' => ldap_errno($this->conn), 'type' => 'ldap',
                'file' => __FILE__, 'line' => __LINE__,
                'message' => "Bind failed for dn=$dn: ".ldap_error($this->conn));
        raise_error($error,true);

        return false;
    }


    /**
    * Close connection to LDAP server
    */
    function close()
    {
        if ($this->conn)
        {
            $this->_debug("C: Close");
            ldap_unbind($this->conn);
            $this->conn = null;
        }
    }


    /**
    * Set internal list page
    *
    * @param  number  Page number to list
    * @access public
    */
    function set_page($page)
    {
        $this->list_page = (int)$page;
    }


    /**
    * Set internal page size
    *
    * @param  number  Number of messages to display on one page
    * @access public
    */
    function set_pagesize($size)
    {
        $this->page_size = (int)$size;
    }


    /**
    * Save a search string for future listings
    *
    * @param string Filter string
    */
    function set_search_set($filter)
    {
        $this->filter = $filter;
    }


    /**
    * Getter for saved search properties
    *
    * @return mixed Search properties used by this class
    */
    function get_search_set()
    {
        return $this->filter;
    }


    /**
    * Reset all saved results and search parameters
    */
    function reset()
    {
        $this->result = null;
        $this->ldap_result = null;
        $this->filter = '';
    }


    /**
    * List the current set of contact records
    *
    * @param  array  List of cols to show
    * @param  int    Only return this number of records
    * @return array  Indexed list of contact records, each a hash array
    */
    function list_records($cols=null, $subset=0)
    {
        // add general filter to query
        if (!empty($this->prop['filter']) && empty($this->filter))
        {
            $filter = $this->prop['filter'];
            $this->set_search_set($filter);
        }

        // exec LDAP search if no result resource is stored
        if ($this->conn && !$this->ldap_result)
            $this->_exec_search();

        // count contacts for this user
        $this->result = $this->count();

        // we have a search result resource
        if ($this->ldap_result && $this->result->count > 0)
        {
            if ($this->sort_col && $this->prop['scope'] !== 'base')
                ldap_sort($this->conn, $this->ldap_result, $this->sort_col);

            $start_row = $subset < 0 ? $this->result->first + $this->page_size + $subset : $this->result->first;
            $last_row = $this->result->first + $this->page_size;
            $last_row = $subset != 0 ? $start_row + abs($subset) : $last_row;

            $entries = ldap_get_entries($this->conn, $this->ldap_result);
            for ($i = $start_row; $i < min($entries['count'], $last_row); $i++)
                $this->result->add($this->_ldap2result($entries[$i]));
        }

        // temp hack for filtering group members
        if ($this->groups and $this->group_id)
        {
            $result = new rcube_result_set();
            while ($record = $this->result->iterate())
            {
                if ($this->group_members[$record['ID']])
                {
                    $result->add($record);
                    $result->count++;
                }
            }
            $this->result = $result;
        }

        return $this->result;
    }


    /**
    * Search contacts
    *
    * @param array   List of fields to search in
    * @param string  Search value
    * @param boolean True for strict, False for partial (fuzzy) matching
    * @param boolean True if results are requested, False if count only
    * @param boolean (Not used)
    * @param array   List of fields that cannot be empty
    * @return array  Indexed list of contact records and 'count' value
    */
    function search($fields, $value, $strict=false, $select=true, $nocount=false, $required=array())
    {
        // special treatment for ID-based search
        if ($fields == 'ID' || $fields == $this->primary_key)
        {
            $ids = explode(',', $value);
            $result = new rcube_result_set();
            foreach ($ids as $id)
            {
                if ($rec = $this->get_record($id, true))
                {
                    $result->add($rec);
                    $result->count++;
                }
            }
            return $result;
        }

        $filter = '(|';
        $wc = !$strict && $this->prop['fuzzy_search'] ? '*' : '';
        if ($fields != '*')
        {
            // search_fields are required for fulltext search
            if (!$this->prop['search_fields'])
            {
                $this->set_error(self::ERROR_SEARCH, 'nofulltextsearch');
                $this->result = new rcube_result_set();
                return $this->result;
            }
        }
        
        if (is_array($this->prop['search_fields']))
        {
            foreach ($this->prop['search_fields'] as $k => $field)
                $filter .= "($field=$wc" . $this->_quote_string($value) . "$wc)";
        }
        else
        {
            foreach ((array)$fields as $field)
                if ($f = $this->_map_field($field))
                    $filter .= "($f=$wc" . $this->_quote_string($value) . "$wc)";
        }
        $filter .= ')';

        // add required (non empty) fields filter
        $req_filter = '';
        foreach ((array)$required as $field)
            if ($f = $this->_map_field($field))
                $req_filter .= "($f=*)";

        if (!empty($req_filter))
            $filter = '(&' . $req_filter . $filter . ')';

        // avoid double-wildcard if $value is empty
        $filter = preg_replace('/\*+/', '*', $filter);

        // add general filter to query
        if (!empty($this->prop['filter']))
            $filter = '(&(' . preg_replace('/^\(|\)$/', '', $this->prop['filter']) . ')' . $filter . ')';

        // set filter string and execute search
        $this->set_search_set($filter);
        $this->_exec_search();

        if ($select)
            $this->list_records();
        else
            $this->result = $this->count();

        return $this->result;
    }


    /**
    * Count number of available contacts in database
    *
    * @return object rcube_result_set Resultset with values for 'count' and 'first'
    */
    function count()
    {
        $count = 0;
        if ($this->conn && $this->ldap_result) {
            $count = ldap_count_entries($this->conn, $this->ldap_result);
        } // end if
        elseif ($this->conn) {
            // We have a connection but no result set, attempt to get one.
            if (empty($this->filter)) {
                // The filter is not set, set it.
                $this->filter = $this->prop['filter'];
            } // end if
            $this->_exec_search();
            if ($this->ldap_result) {
                $count = ldap_count_entries($this->conn, $this->ldap_result);
            } // end if
        } // end else

        return new rcube_result_set($count, ($this->list_page-1) * $this->page_size);
    }


    /**
    * Return the last result set
    *
    * @return object rcube_result_set Current resultset or NULL if nothing selected yet
    */
    function get_result()
    {
        return $this->result;
    }


    /**
    * Get a specific contact record
    *
    * @param mixed   Record identifier
    * @param boolean Return as associative array
    * @return mixed  Hash array or rcube_result_set with all record fields
    */
    function get_record($dn, $assoc=false)
    {
        $res = null;
        if ($this->conn && $dn)
        {
            $dn = base64_decode($dn);

            $this->_debug("C: Read [dn: $dn] [(objectclass=*)]");

            if ($this->ldap_result = @ldap_read($this->conn, $dn, '(objectclass=*)', array_values($this->fieldmap)))
                $entry = ldap_first_entry($this->conn, $this->ldap_result);
            else
                $this->_debug("S: ".ldap_error($this->conn));

            if ($entry && ($rec = ldap_get_attributes($this->conn, $entry)))
            {
                $this->_debug("S: OK"/* . print_r($rec, true)*/);

                $rec = array_change_key_case($rec, CASE_LOWER);

                // Add in the dn for the entry.
                $rec['dn'] = $dn;
                $res = $this->_ldap2result($rec);
                $this->result = new rcube_result_set(1);
                $this->result->add($res);
            }
        }

        return $assoc ? $res : $this->result;
    }


    /**
    * Create a new contact record
    *
    * @param array    Hash array with save data
    * @return encoded record ID on success, False on error
    */
    function insert($save_cols)
    {
        // Map out the column names to their LDAP ones to build the new entry.
        $newentry = array();
        $newentry['objectClass'] = $this->prop['LDAP_Object_Classes'];
        foreach ($this->fieldmap as $col => $fld) {
            $val = $save_cols[$col];
            if (is_array($val))
                $val = array_filter($val);  // remove empty entries
            if ($fld && $val) {
                // The field does exist, add it to the entry.
                $newentry[$fld] = $val;
            } // end if
        } // end foreach

        // Verify that the required fields are set.
        foreach ($this->prop['required_fields'] as $fld) {
            $missing = null;
            if (!isset($newentry[$fld])) {
                $missing[] = $fld;
            }
        }

        // abort process if requiered fields are missing
        // TODO: generate message saying which fields are missing
        if ($missing) {
            $this->set_error(self::ERROR_INCOMPLETE, 'formincomplete');
            return false;
        }

        // Build the new entries DN.
        $dn = $this->prop['LDAP_rdn'].'='.$this->_quote_string($newentry[$this->prop['LDAP_rdn']], true).','.$this->prop['base_dn'];

        $this->_debug("C: Add [dn: $dn]: ".print_r($newentry, true));

        $res = ldap_add($this->conn, $dn, $newentry);
        if ($res === FALSE) {
            $this->_debug("S: ".ldap_error($this->conn));
            $this->set_error(self::ERROR_SAVING, 'errorsaving');
            return false;
        } // end if

        $this->_debug("S: OK");

        // add new contact to the selected group
        if ($this->groups)
            $this->add_to_group($this->group_id, base64_encode($dn));

        return base64_encode($dn);
    }


    /**
    * Update a specific contact record
    *
    * @param mixed Record identifier
    * @param array Hash array with save data
    * @return boolean True on success, False on error
    */
    function update($id, $save_cols)
    {
        $record = $this->get_record($id, true);
        $result = $this->get_result();
        $record = $result->first();

        $newdata = array();
        $replacedata = array();
        $deletedata = array();
        foreach ($this->fieldmap as $col => $fld) {
            $val = $save_cols[$col];
            if ($fld) {
                // remove empty array values
                if (is_array($val))
                    $val = array_filter($val);
                // The field does exist compare it to the ldap record.
                if ($record[$col] != $val) {
                    // Changed, but find out how.
                    if (!isset($record[$col])) {
                        // Field was not set prior, need to add it.
                        $newdata[$fld] = $val;
                    } // end if
                    elseif ($val == '') {
                        // Field supplied is empty, verify that it is not required.
                        if (!in_array($fld, $this->prop['required_fields'])) {
                            // It is not, safe to clear.
                            $deletedata[$fld] = $record[$col];
                        } // end if
                    } // end elseif
                    else {
                        // The data was modified, save it out.
                        $replacedata[$fld] = $val;
                    } // end else
                } // end if
            } // end if
        } // end foreach

        $dn = base64_decode($id);

        // Update the entry as required.
        if (!empty($deletedata)) {
            // Delete the fields.
            $this->_debug("C: Delete [dn: $dn]: ".print_r($deletedata, true));
            if (!ldap_mod_del($this->conn, $dn, $deletedata)) {
                $this->_debug("S: ".ldap_error($this->conn));
                $this->set_error(self::ERROR_SAVING, 'errorsaving');
                return false;
            }
            $this->_debug("S: OK");
        } // end if

        if (!empty($replacedata)) {
            // Handle RDN change
            if ($replacedata[$this->prop['LDAP_rdn']]) {
                $newdn = $this->prop['LDAP_rdn'].'='
                    .$this->_quote_string($replacedata[$this->prop['LDAP_rdn']], true)
                    .','.$this->prop['base_dn'];
                if ($dn != $newdn) {
                    $newrdn = $this->prop['LDAP_rdn'].'='
                    .$this->_quote_string($replacedata[$this->prop['LDAP_rdn']], true);
                    unset($replacedata[$this->prop['LDAP_rdn']]);
                }
            }
            // Replace the fields.
            if (!empty($replacedata)) {
                $this->_debug("C: Replace [dn: $dn]: ".print_r($replacedata, true));
                if (!ldap_mod_replace($this->conn, $dn, $replacedata)) {
                    $this->_debug("S: ".ldap_error($this->conn));
                    return false;
                }
                $this->_debug("S: OK");
            } // end if
        } // end if

        if (!empty($newdata)) {
            // Add the fields.
            $this->_debug("C: Add [dn: $dn]: ".print_r($newdata, true));
            if (!ldap_mod_add($this->conn, $dn, $newdata)) {
                $this->_debug("S: ".ldap_error($this->conn));
                $this->set_error(self::ERROR_SAVING, 'errorsaving');
                return false;
            }
            $this->_debug("S: OK");
        } // end if

        // Handle RDN change
        if (!empty($newrdn)) {
            $this->_debug("C: Rename [dn: $dn] [dn: $newrdn]");
            if (!ldap_rename($this->conn, $dn, $newrdn, NULL, TRUE)) {
                $this->_debug("S: ".ldap_error($this->conn));
                return false;
            }
            $this->_debug("S: OK");

            // change the group membership of the contact
            if ($this->groups)
            {
                $group_ids = $this->get_record_groups(base64_encode($dn));
                foreach ($group_ids as $group_id)
                {
                    $this->remove_from_group($group_id, base64_encode($dn));
                    $this->add_to_group($group_id, base64_encode($newdn));
                }
            }
            return base64_encode($newdn);
        }

        return true;
    }


    /**
    * Mark one or more contact records as deleted
    *
    * @param array  Record identifiers
    * @return boolean True on success, False on error
    */
    function delete($ids)
    {
        if (!is_array($ids)) {
            // Not an array, break apart the encoded DNs.
            $dns = explode(',', $ids);
        } // end if

        foreach ($dns as $id) {
            $dn = base64_decode($id);
            $this->_debug("C: Delete [dn: $dn]");
            // Delete the record.
            $res = ldap_delete($this->conn, $dn);
            if ($res === FALSE) {
                $this->_debug("S: ".ldap_error($this->conn));
                $this->set_error(self::ERROR_SAVING, 'errorsaving');
                return false;
            } // end if
            $this->_debug("S: OK");

            // remove contact from all groups where he was member
            if ($this->groups)
            {
                $group_ids = $this->get_record_groups(base64_encode($dn));
                foreach ($group_ids as $group_id)
                {
                    $this->remove_from_group($group_id, base64_encode($dn));
                }
            }
        } // end foreach

        return count($dns);
    }


    /**
    * Execute the LDAP search based on the stored credentials
    *
    * @access private
    */
    private function _exec_search()
    {
        if ($this->ready)
        {
            $filter = $this->filter ? $this->filter : '(objectclass=*)';
            $function = $this->prop['scope'] == 'sub' ? 'ldap_search' : ($this->prop['scope'] == 'base' ? 'ldap_read' : 'ldap_list');

            $this->_debug("C: Search [".$filter."]");

            if ($this->ldap_result = @$function($this->conn, $this->prop['base_dn'], $filter,
                array_values($this->fieldmap), 0, (int) $this->prop['sizelimit'], (int) $this->prop['timelimit']))
            {
                $this->_debug("S: ".ldap_count_entries($this->conn, $this->ldap_result)." record(s)");
                return true;
            }
            else
            {
                $this->_debug("S: ".ldap_error($this->conn));
            }
        }

        return false;
    }


    /**
    * @access private
    */
    private function _ldap2result($rec)
    {
        $out = array();

        if ($rec['dn'])
            $out[$this->primary_key] = base64_encode($rec['dn']);

        foreach ($this->fieldmap as $rf => $lf)
        {
            for ($i=0; $i < $rec[$lf]['count']; $i++) {
                if (!($value = $rec[$lf][$i]))
                    continue;
                if ($rf == 'email' && $this->mail_domain && !strpos($value, '@'))
                    $out[$rf][] = sprintf('%s@%s', $value, $this->mail_domain);
                else if (in_array($rf, array('street','zipcode','locality','country','region')))
                    $out['address'][$i][$rf] = $value;
                else if ($rec[$lf]['count'] > 1)
                    $out[$rf][] = $value;
                else
                    $out[$rf] = $value;
            }
        }

        return $out;
    }


    /**
    * @access private
    */
    private function _map_field($field)
    {
        return $this->fieldmap[$field];
    }


    /**
    * @access private
    */
    private function _attr_name($name)
    {
        // list of known attribute aliases
        $aliases = array(
            'gn' => 'givenname',
            'rfc822mailbox' => 'email',
            'userid' => 'uid',
            'emailaddress' => 'email',
            'pkcs9email' => 'email',
        );
        return isset($aliases[$name]) ? $aliases[$name] : $name;
    }


    /**
    * @access private
    */
    private function _debug($str)
    {
        if ($this->debug)
            write_log('ldap', $str);
    }


    /**
    * @static
    */
    private function _quote_string($str, $dn=false)
    {
        // take firt entry if array given
        if (is_array($str))
            $str = reset($str);

        if ($dn)
            $replace = array(','=>'\2c', '='=>'\3d', '+'=>'\2b', '<'=>'\3c',
                '>'=>'\3e', ';'=>'\3b', '\\'=>'\5c', '"'=>'\22', '#'=>'\23');
        else
            $replace = array('*'=>'\2a', '('=>'\28', ')'=>'\29', '\\'=>'\5c',
                '/'=>'\2f');

        return strtr($str, $replace);
    }


    /**
     * Setter for the current group
     * (empty, has to be re-implemented by extending class)
     */
    function set_group($group_id)
    {
        if ($group_id)
        {
            if (!$this->group_cache)
                $this->list_groups();

            $cache_members = $this->group_cache[$group_id]['members'];

            $members = array();
            for ($i=1; $i<$cache_members["count"]; $i++)
            {
                $members[base64_encode($cache_members[$i])] = 1;
            }
            $this->group_members = $members;
            $this->group_id = $group_id;
        }
        else
            $this->group_id = 0;
    }

    /**
     * List all active contact groups of this source
     *
     * @param string  Optional search string to match group name
     * @return array  Indexed list of contact groups, each a hash array
     */
    function list_groups($search = null)
    {
        if (!$this->groups)
            return array();

        $base_dn = $this->prop['groups']['base_dn'];
        $filter = '(objectClass=groupOfNames)';

        $res = ldap_search($this->conn, $base_dn, $filter, array('cn','member'));
        if ($res === false)
        {
            $this->_debug("S: ".ldap_error($this->conn));
            $this->set_error(self::ERROR_SAVING, 'errorsaving');
            return array();
        }
        $ldap_data = ldap_get_entries($this->conn, $res);

        $groups = array();
        $group_sortnames = array();
        for ($i=0; $i<$ldap_data["count"]; $i++)
        {
            $group_name = $ldap_data[$i]['cn'][0];
            $group_id = base64_encode($group_name);
            $groups[$group_id]['ID'] = $group_id;
            $groups[$group_id]['name'] = $group_name;
            $groups[$group_id]['members'] = $ldap_data[$i]['member'];
            $group_sortnames[] = strtolower($group_name);
        }
        array_multisort($group_sortnames, SORT_ASC, SORT_STRING, $groups);
        $this->group_cache = $groups;

        return $groups;
    }

    /**
     * Create a contact group with the given name
     *
     * @param string The group name
     * @return mixed False on error, array with record props in success
     */
    function create_group($group_name)
    {
        if (!$this->group_cache)
            $this->list_groups();

        $base_dn = $this->prop['groups']['base_dn'];
        $new_dn = "cn=$group_name,$base_dn";
        $new_gid = base64_encode($group_name);

        $new_entry = array(
            'objectClass' => array('top', 'groupOfNames'),
            'cn' => $group_name,
            'member' => '',
        );

        $res = ldap_add($this->conn, $new_dn, $new_entry);
        if ($res === false)
        {
            $this->_debug("S: ".ldap_error($this->conn));
            $this->set_error(self::ERROR_SAVING, 'errorsaving');
            return false;
        }
        return array('id' => $new_gid, 'name' => $group_name);
    }

    /**
     * Delete the given group and all linked group members
     *
     * @param string Group identifier
     * @return boolean True on success, false if no data was changed
     */
    function delete_group($group_id)
    {
        if (!$this->group_cache)
            $this->list_groups();

        $base_dn = $this->prop['groups']['base_dn'];
        $group_name = $this->group_cache[$group_id]['name'];

        $del_dn = "cn=$group_name,$base_dn";
        $res = ldap_delete($this->conn, $del_dn);
        if ($res === false)
        {
            $this->_debug("S: ".ldap_error($this->conn));
            $this->set_error(self::ERROR_SAVING, 'errorsaving');
            return false;
        }
        return true;
    }

    /**
     * Rename a specific contact group
     *
     * @param string Group identifier
     * @param string New name to set for this group
     * @param string New group identifier (if changed, otherwise don't set)
     * @return boolean New name on success, false if no data was changed
     */
    function rename_group($group_id, $new_name, &$new_id)
    {
        if (!$this->group_cache)
            $this->list_groups();

        $base_dn = $this->prop['groups']['base_dn'];
        $group_name = $this->group_cache[$group_id]['name'];
        $old_dn = "cn=$group_name,$base_dn";
        $new_rdn = "cn=$new_name";
        $new_id = base64_encode($new_rdn . ",$base_dn");

        $res = ldap_rename($this->conn, $old_dn, $new_rdn, NULL, TRUE);
        if ($res === false)
        {
            $this->_debug("S: ".ldap_error($this->conn));
            $this->set_error(self::ERROR_SAVING, 'errorsaving');
            return false;
        }
        return $new_name;
    }

    /**
     * Add the given contact records the a certain group
     *
     * @param string  Group identifier
     * @param array   List of contact identifiers to be added
     * @return int    Number of contacts added
     */
    function add_to_group($group_id, $contact_ids)
    {
        if (!$this->group_cache)
            $this->list_groups();

        $base_dn = $this->prop['groups']['base_dn'];
        $group_name = $this->group_cache[$group_id]['name'];
        $group_dn = "cn=$group_name,$base_dn";

        $new_attrs = array();
        foreach (explode(",", $contact_ids) as $id)
            $new_attrs['member'][] = base64_decode($id);

        $res = ldap_mod_add($this->conn, $group_dn, $new_attrs);
        if ($res === false)
        {
            $this->_debug("S: ".ldap_error($this->conn));
            $this->set_error(self::ERROR_SAVING, 'errorsaving');
            return 0;
        }
        return count($new_attrs['member']);
    }

    /**
     * Remove the given contact records from a certain group
     *
     * @param string  Group identifier
     * @param array   List of contact identifiers to be removed
     * @return int    Number of deleted group members
     */
    function remove_from_group($group_id, $contact_ids)
    {
        if (!$this->group_cache)
            $this->list_groups();

        $base_dn = $this->prop['groups']['base_dn'];
        $group_name = $this->group_cache[$group_id]['name'];
        $group_dn = "cn=$group_name,$base_dn";

        $del_attrs = array();
        foreach (explode(",", $contact_ids) as $id)
            $del_attrs['member'][] = base64_decode($id);

        $res = ldap_mod_del($this->conn, $group_dn, $del_attrs);
        if ($res === false)
        {
            $this->_debug("S: ".ldap_error($this->conn));
            $this->set_error(self::ERROR_SAVING, 'errorsaving');
            return 0;
        }
        return count($del_attrs['member']);
    }

    /**
     * Get group assignments of a specific contact record
     *
     * @param mixed Record identifier
     *
     * @return array List of assigned groups as ID=>Name pairs
     * @since 0.5-beta
     */
    function get_record_groups($contact_id)
    {
        if (!$this->groups)
            return array();

        $base_dn = $this->prop['groups']['base_dn'];
        $contact_dn = base64_decode($contact_id);
        $filter = "(member=$contact_dn)";

        $res = ldap_search($this->conn, $base_dn, $filter, array('cn'));
        if ($res === false)
        {
            $this->_debug("S: ".ldap_error($this->conn));
            $this->set_error(self::ERROR_SAVING, 'errorsaving');
            return array();
        }
        $ldap_data = ldap_get_entries($this->conn, $res);

        $groups = array();
        for ($i=0; $i<$ldap_data["count"]; $i++)
        {
            $group_name = $ldap_data[$i]['cn'][0];
            $group_id = base64_encode($group_name);
            $groups[$group_id] = $group_id;
        }
        return $groups;
    }
}