Merge branch 'master' of github.com:roundcube/roundcubemail

1 files changed, 347 insertions, 770 deletions

diff --git a/program/lib/Roundcube/rcube_ldap.php b/program/lib/Roundcube/rcube_ldap.php
index 39a48b456..54077c692 100644
--- a/program/lib/Roundcube/rcube_ldap.php
+++ b/program/lib/Roundcube/rcube_ldap.php
@@ -3,8 +3,8 @@
 /*
  +-----------------------------------------------------------------------+
  | This file is part of the Roundcube Webmail client                     |
- | Copyright (C) 2006-2012, The Roundcube Dev Team                       |
- | Copyright (C) 2011-2012, Kolab Systems AG                             |
+ | Copyright (C) 2006-2013, The Roundcube Dev Team                       |
+ | Copyright (C) 2011-2013, Kolab Systems AG                             |
  |                                                                       |
  | Licensed under the GNU General Public License version 3 or            |
  | any later version with exceptions for skins & plugins.                |
@@ -36,7 +36,7 @@ class rcube_ldap extends rcube_addressbook
     public $coltypes = array();
 
     /** private properties */
-    protected $conn;
+    protected $ldap;
     protected $prop = array();
     protected $fieldmap = array();
     protected $sub_filter;
@@ -51,14 +51,11 @@ class rcube_ldap extends rcube_addressbook
     private $group_url = null;
     private $cache;
 
-    private $vlv_active = false;
-    private $vlv_count = 0;
-
 
     /**
     * Object constructor
     *
-    * @param array 	 $p            LDAP connection properties
+    * @param array   $p            LDAP connection properties
     * @param boolean $debug        Enables debug mode
     * @param string  $mail_domain  Current user mail domain name
     */
@@ -66,6 +63,8 @@ class rcube_ldap extends rcube_addressbook
     {
         $this->prop = $p;
 
+        $fetch_attributes = array('objectClass');
+
         if (isset($p['searchonly']))
             $this->searchonly = $p['searchonly'];
 
@@ -82,6 +81,17 @@ class rcube_ldap extends rcube_addressbook
                 $this->prop['groups']['name_attr'] = 'cn';
             if (empty($this->prop['groups']['scope']))
                 $this->prop['groups']['scope'] = 'sub';
+
+            // add group name attrib to the list of attributes to be fetched
+            $fetch_attributes[] = $this->prop['groups']['name_attr'];
+        }
+        if (is_array($p['group_filters']) && count($p['group_filters'])) {
+            $this->groups = true;
+
+            foreach ($p['group_filters'] as $group_filter) {
+                if ($group_filter['name_attr'])
+                    $fetch_attributes[] = $group_filter['name_attr'];
+            }
         }
 
         // fieldmap property is given
@@ -185,12 +195,25 @@ class rcube_ldap extends rcube_addressbook
         $this->mail_domain = $mail_domain;
 
         // initialize cache
-        $rcube      = rcube::get_instance();
-        $cache_type = $rcube->config->get('ldap_cache', 'db');
-        $cache_ttl  = $rcube->config->get('ldap_cache_ttl', '10m');
-        $cache_name = 'LDAP.' . asciiwords($this->prop['name']);
+        $rcube = rcube::get_instance();
+        if ($cache_type = $rcube->config->get('ldap_cache', 'db')) {
+            $cache_ttl  = $rcube->config->get('ldap_cache_ttl', '10m');
+            $cache_name = 'LDAP.' . asciiwords($this->prop['name']);
+
+            $this->cache = $rcube->get_cache($cache_name, $cache_type, $cache_ttl);
+        }
+
+        // determine which attributes to fetch
+        $this->prop['list_attributes'] = array_unique($fetch_attributes);
+        $this->prop['attributes'] = array_merge(array_values($this->fieldmap), $fetch_attributes);
+        foreach ($rcube->config->get('contactlist_fields') as $col) {
+            $this->prop['list_attributes'] = array_merge($this->prop['list_attributes'], $this->_map_field($col));
+        }
 
-        $this->cache = $rcube->get_cache($cache_name, $cache_type, $cache_ttl);
+        // initialize ldap wrapper object
+        $this->ldap = new rcube_ldap_generic($this->prop);
+        $this->ldap->set_cache($this->cache);
+        $this->ldap->set_debug($this->debug);
 
         $this->_connect();
     }
@@ -203,49 +226,18 @@ class rcube_ldap extends rcube_addressbook
     {
         $rcube = rcube::get_instance();
 
-        if (!function_exists('ldap_connect'))
-            rcube::raise_error(array('code' => 100, 'type' => 'ldap',
-                'file' => __FILE__, 'line' => __LINE__,
-                'message' => "No ldap support in this installation of PHP"),
-                true, true);
-
-        if (is_resource($this->conn))
+        if ($this->ready)
             return true;
 
         if (!is_array($this->prop['hosts']))
             $this->prop['hosts'] = array($this->prop['hosts']);
 
-        if (empty($this->prop['ldap_version']))
-            $this->prop['ldap_version'] = 3;
-
         // try to connect + bind for every host configured
         // with OpenLDAP 2.x ldap_connect() always succeeds but ldap_bind will fail if host isn't reachable
         // see http://www.php.net/manual/en/function.ldap-connect.php
         foreach ($this->prop['hosts'] as $host) {
-            $host     = rcube_utils::idn_to_ascii(rcube_utils::parse_host($host));
-            $hostname = $host.($this->prop['port'] ? ':'.$this->prop['port'] : '');
-
-            $this->_debug("C: Connect [$hostname] [{$this->prop['name']}]");
-
-            if ($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 = $lc;
-
-                if (!empty($this->prop['network_timeout']))
-                  ldap_set_option($lc, LDAP_OPT_NETWORK_TIMEOUT, $this->prop['network_timeout']);
-
-                if (isset($this->prop['referrals']))
-                    ldap_set_option($lc, LDAP_OPT_REFERRALS, $this->prop['referrals']);
-            }
-            else {
-                $this->_debug("S: NOT OK");
+            // skip host if connection failed
+            if (!$this->ldap->connect($host)) {
                 continue;
             }
 
@@ -260,7 +252,7 @@ class rcube_ldap extends rcube_addressbook
 
             $this->base_dn        = $this->prop['base_dn'];
             $this->groups_base_dn = ($this->prop['groups']['base_dn']) ?
-            $this->prop['groups']['base_dn'] : $this->base_dn;
+                $this->prop['groups']['base_dn'] : $this->base_dn;
 
             // User specific access, generate the proper values to use.
             if ($this->prop['user_specific']) {
@@ -279,29 +271,46 @@ class rcube_ldap extends rcube_addressbook
 
                 $replaces = array('%dn' => '', '%dc' => $dc, '%d' => $d, '%fu' => $fu, '%u' => $u);
 
+                // Search for the dn to use to authenticate
                 if ($this->prop['search_base_dn'] && $this->prop['search_filter']) {
-                    if (!empty($this->prop['search_bind_dn']) && !empty($this->prop['search_bind_pw'])) {
-                        $this->bind($this->prop['search_bind_dn'], $this->prop['search_bind_pw']);
-                    }
-
-                    // 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);
+                    $search_bind_dn = strtr($this->prop['search_bind_dn'], $replaces);
+                    $search_base_dn = strtr($this->prop['search_base_dn'], $replaces);
+                    $search_filter  = strtr($this->prop['search_filter'], $replaces);
 
-                    $this->_debug("S: searching with base {$this->prop['search_base_dn']} for {$this->prop['search_filter']}");
+                    $cache_key = 'DN.' . md5("$host:$search_bind_dn:$search_base_dn:$search_filter:"
+                        .$this->prop['search_bind_pw']);
 
-                    $res = @ldap_search($this->conn, $this->prop['search_base_dn'], $this->prop['search_filter'], array('uid'));
-                    if ($res) {
-                        if (($entry = ldap_first_entry($this->conn, $res))
-                            && ($bind_dn = ldap_get_dn($this->conn, $entry))
-                        ) {
-                            $this->_debug("S: search returned dn: $bind_dn");
-                            $dn = ldap_explode_dn($bind_dn, 1);
-                            $replaces['%dn'] = $dn[0];
-                        }
+                    if ($this->cache && ($dn = $this->cache->get($cache_key))) {
+                        $replaces['%dn'] = $dn;
                     }
                     else {
-                        $this->_debug("S: ".ldap_error($this->conn));
+                        $ldap = $this->ldap;
+                        if (!empty($search_bind_dn) && !empty($this->prop['search_bind_pw'])) {
+                            // To protect from "Critical extension is unavailable" error
+                            // we need to use a separate LDAP connection
+                            if (!empty($this->prop['vlv'])) {
+                                $ldap = new rcube_ldap_generic($this->prop);
+                                $ldap->set_debug($this->debug);
+                                $ldap->set_cache($this->cache);
+                                if (!$ldap->connect($host)) {
+                                    continue;
+                                }
+                            }
+
+                            if (!$ldap->bind($search_bind_dn, $this->prop['search_bind_pw'])) {
+                                continue;  // bind failed, try next host
+                            }
+                        }
+
+                        $res = $ldap->search($search_base_dn, $search_filter, 'sub', array('uid'));
+                        if ($res) {
+                            $res->rewind();
+                            $replaces['%dn'] = $res->get_dn();
+                        }
+
+                        if ($ldap != $this->ldap) {
+                            $ldap->close();
+                        }
                     }
 
                     // DN not found
@@ -313,9 +322,13 @@ class rcube_ldap extends rcube_addressbook
                                 'code' => 100, 'type' => 'ldap',
                                 'file' => __FILE__, 'line' => __LINE__,
                                 'message' => "DN not found using LDAP search."), true);
-                            return false;
+                            continue;
                         }
                     }
+
+                    if ($this->cache && !empty($replaces['%dn'])) {
+                        $this->cache->set($cache_key, $replaces['%dn']);
+                    }
                 }
 
                 // Replace the bind_dn and base_dn variables.
@@ -333,13 +346,13 @@ class rcube_ldap extends rcube_addressbook
             }
             else {
                 if (!empty($bind_dn)) {
-                    $this->ready = $this->bind($bind_dn, $bind_pass);
+                    $this->ready = $this->ldap->bind($bind_dn, $bind_pass);
                 }
                 else if (!empty($this->prop['auth_cid'])) {
-                    $this->ready = $this->sasl_bind($this->prop['auth_cid'], $bind_pass, $bind_user);
+                    $this->ready = $this->ldap->sasl_bind($this->prop['auth_cid'], $bind_pass, $bind_user);
                 }
                 else {
-                    $this->ready = $this->sasl_bind($bind_user, $bind_pass);
+                    $this->ready = $this->ldap->sasl_bind($bind_user, $bind_pass);
                 }
             }
 
@@ -350,10 +363,10 @@ class rcube_ldap extends rcube_addressbook
 
         }  // end foreach hosts
 
-        if (!is_resource($this->conn)) {
+        if (!is_resource($this->ldap->conn)) {
             rcube::raise_error(array('code' => 100, 'type' => 'ldap',
                 'file' => __FILE__, 'line' => __LINE__,
-                'message' => "Could not connect to any LDAP server, last tried $hostname"), true);
+                'message' => "Could not connect to any LDAP server, last tried $host"), true);
 
             return false;
         }
@@ -363,112 +376,47 @@ class rcube_ldap extends rcube_addressbook
 
 
     /**
-     * Bind connection with (SASL-) user and password
-     *
-     * @param string $authc Authentication user
-     * @param string $pass  Bind password
-     * @param string $authz Autorization user
-     *
-     * @return boolean True on success, False on error
+     * Close connection to LDAP server
      */
-    public function sasl_bind($authc, $pass, $authz=null)
+    function close()
     {
-        if (!$this->conn) {
-            return false;
-        }
-
-        if (!function_exists('ldap_sasl_bind')) {
-            rcube::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)) {
-            $this->_debug("S: OK");
-            return true;
+        if ($this->ldap) {
+            $this->ldap->close();
         }
-
-        $this->_debug("S: ".ldap_error($this->conn));
-
-        rcube::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
+     * Returns address book name
      *
-     * @return boolean True on success, False on error
+     * @return string Address book name
      */
-    public function bind($dn, $pass)
+    function get_name()
     {
-        if (!$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));
-
-        rcube::raise_error(array(
-            'code' => ldap_errno($this->conn), 'type' => 'ldap',
-            'file' => __FILE__, 'line' => __LINE__,
-            'message' => "Bind failed for dn=$dn: ".ldap_error($this->conn)),
-            true);
-
-        return false;
+        return $this->prop['name'];
     }
 
 
     /**
-     * Close connection to LDAP server
+     * Set internal list page
+     *
+     * @param  number  Page number to list
      */
-    function close()
+    function set_page($page)
     {
-        if ($this->conn)
-        {
-            $this->_debug("C: Close");
-            ldap_unbind($this->conn);
-            $this->conn = null;
-        }
+        $this->list_page = (int)$page;
+        $this->ldap->set_vlv_page($this->list_page, $this->page_size);
     }
 
-
     /**
-     * Returns address book name
+     * Set internal page size
      *
-     * @return string Address book name
+     * @param  number  Number of records to display on one page
      */
-    function get_name()
+    function set_pagesize($size)
     {
-        return $this->prop['name'];
+        $this->page_size = (int)$size;
+        $this->ldap->set_vlv_page($this->list_page, $this->page_size);
     }
 
 
@@ -528,16 +476,14 @@ class rcube_ldap extends rcube_addressbook
      */
     function list_records($cols=null, $subset=0)
     {
-        if ($this->prop['searchonly'] && empty($this->filter) && !$this->group_id)
-        {
+        if ($this->prop['searchonly'] && empty($this->filter) && !$this->group_id) {
             $this->result = new rcube_result_set(0);
             $this->result->searchonly = true;
             return $this->result;
         }
 
         // fetch group members recursively
-        if ($this->group_id && $this->group_data['dn'])
-        {
+        if ($this->group_id && $this->group_data['dn']) {
             $entries = $this->list_group_members($this->group_data['dn']);
 
             // make list of entries unique and sort it
@@ -551,34 +497,34 @@ class rcube_ldap extends rcube_addressbook
             $entries['count'] = count($entries);
             $this->result = new rcube_result_set($entries['count'], ($this->list_page-1) * $this->page_size);
         }
-        else
-        {
-            // add general filter to query
-            if (!empty($this->prop['filter']) && empty($this->filter))
-                $this->set_search_set($this->prop['filter']);
+        else {
+            $prop = $this->group_id ? $this->group_data : $this->prop;
+
+            // use global search filter
+            if (!empty($this->filter))
+                $prop['filter'] = $this->filter;
 
             // exec LDAP search if no result resource is stored
-            if ($this->conn && !$this->ldap_result)
-                $this->_exec_search();
+            if ($this->ready && !$this->ldap_result)
+                $this->ldap_result = $this->ldap->search($prop['base_dn'], $prop['filter'], $prop['scope'], $this->prop['attributes'], $prop);
 
             // 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->ldap_result && $this->result->count > 0) {
                 // sorting still on the ldap server
-                if ($this->sort_col && $this->prop['scope'] !== 'base' && !$this->vlv_active)
-                    ldap_sort($this->conn, $this->ldap_result, $this->sort_col);
+                if ($this->sort_col && $prop['scope'] !== 'base' && !$this->ldap->vlv_active)
+                    $this->ldap_result->sort($this->sort_col);
 
                 // get all entries from the ldap server
-                $entries = ldap_get_entries($this->conn, $this->ldap_result);
+                $entries = $this->ldap_result->entries();
             }
 
         }  // end else
 
         // start and end of the page
-        $start_row = $this->vlv_active ? 0 : $this->result->first;
+        $start_row = $this->ldap->vlv_active ? 0 : $this->result->first;
         $start_row = $subset < 0 ? $start_row + $this->page_size + $subset : $start_row;
         $last_row = $this->result->first + $this->page_size;
         $last_row = $subset != 0 ? $start_row + abs($subset) : $last_row;
@@ -603,25 +549,19 @@ class rcube_ldap extends rcube_addressbook
 
         // fetch group object
         if (empty($entries)) {
-            $result = @ldap_read($this->conn, $dn, '(objectClass=*)', array('dn','objectClass','member','uniqueMember','memberURL'));
-            if ($result === false)
-            {
-                $this->_debug("S: ".ldap_error($this->conn));
+            $entries = $this->ldap->read_entries($dn, '(objectClass=*)', array('dn','objectClass','member','uniqueMember','memberURL'));
+            if ($entries === false) {
                 return $group_members;
             }
-
-            $entries = @ldap_get_entries($this->conn, $result);
         }
 
-        for ($i=0; $i < $entries['count']; $i++)
-        {
+        for ($i=0; $i < $entries['count']; $i++) {
             $entry = $entries[$i];
 
             if (empty($entry['objectclass']))
                 continue;
 
-            foreach ((array)$entry['objectclass'] as $objectclass)
-            {
+            foreach ((array)$entry['objectclass'] as $objectclass) {
                 switch (strtolower($objectclass)) {
                     case "group":
                     case "groupofnames":
@@ -662,24 +602,19 @@ class rcube_ldap extends rcube_addressbook
             return $group_members;
 
         // read these attributes for all members
-        $attrib = $count ? array('dn') : array_values($this->fieldmap);
-        $attrib[] = 'objectClass';
+        $attrib = $count ? array('dn','objectClass') : $this->prop['list_attributes'];
         $attrib[] = 'member';
         $attrib[] = 'uniqueMember';
         $attrib[] = 'memberURL';
 
-        for ($i=0; $i < $entry[$attr]['count']; $i++)
-        {
+        $filter = $this->prop['groups']['member_filter'] ? $this->prop['groups']['member_filter'] : '(objectclass=*)';
+
+        for ($i=0; $i < $entry[$attr]['count']; $i++) {
             if (empty($entry[$attr][$i]))
                 continue;
 
-            $result = @ldap_read($this->conn, $entry[$attr][$i], '(objectclass=*)',
-                $attrib, 0, (int)$this->prop['sizelimit'], (int)$this->prop['timelimit']);
-
-            $members = @ldap_get_entries($this->conn, $result);
-            if ($members == false)
-            {
-                $this->_debug("S: ".ldap_error($this->conn));
+            $members = $this->ldap->read_entries($entry[$attr][$i], $filter, $attrib);
+            if ($members == false) {
                 $members = array();
             }
 
@@ -705,34 +640,22 @@ class rcube_ldap extends rcube_addressbook
     {
         $group_members = array();
 
-        for ($i=0; $i < $entry['memberurl']['count']; $i++)
-        {
+        for ($i=0; $i < $entry['memberurl']['count']; $i++) {
             // extract components from url
             if (!preg_match('!ldap:///([^\?]+)\?\?(\w+)\?(.*)$!', $entry['memberurl'][$i], $m))
                 continue;
 
             // add search filter if any
             $filter = $this->filter ? '(&(' . $m[3] . ')(' . $this->filter . '))' : $m[3];
-            $func = $m[2] == 'sub' ? 'ldap_search' : ($m[2] == 'base' ? 'ldap_read' : 'ldap_list');
-
-            $attrib = $count ? array('dn') : array_values($this->fieldmap);
-            if ($result = @$func($this->conn, $m[1], $filter,
-                $attrib, 0, (int)$this->prop['sizelimit'], (int)$this->prop['timelimit'])
-            ) {
-                $this->_debug("S: ".ldap_count_entries($this->conn, $result)." record(s) for ".$m[1]);
-            }
-            else {
-                $this->_debug("S: ".ldap_error($this->conn));
-                return $group_members;
-            }
-
-            $entries = @ldap_get_entries($this->conn, $result);
-            for ($j = 0; $j < $entries['count']; $j++)
-            {
-                if ($nested_group_members = $this->list_group_members($entries[$j]['dn'], $count))
-                    $group_members = array_merge($group_members, $nested_group_members);
-                else
-                    $group_members[] = $entries[$j];
+            $attrs = $count ? array('dn','objectClass') : $this->prop['list_attributes'];
+            if ($result = $this->ldap->search($m[1], $filter, $m[2], $attrs, $this->group_data)) {
+                $entries = $result->entries();
+                for ($j = 0; $j < $entries['count']; $j++) {
+                    if (self::is_group_entry($entries[$j]) && ($nested_group_members = $this->list_group_members($entries[$j]['dn'], $count)))
+                        $group_members = array_merge($group_members, $nested_group_members);
+                    else
+                        $group_members[] = $entries[$j];
+                }
             }
         }
 
@@ -768,14 +691,11 @@ class rcube_ldap extends rcube_addressbook
         $mode = intval($mode);
 
         // special treatment for ID-based search
-        if ($fields == 'ID' || $fields == $this->primary_key)
-        {
+        if ($fields == 'ID' || $fields == $this->primary_key) {
             $ids = !is_array($value) ? explode(',', $value) : $value;
             $result = new rcube_result_set();
-            foreach ($ids as $id)
-            {
-                if ($rec = $this->get_record($id, true))
-                {
+            foreach ($ids as $id) {
+                if ($rec = $this->get_record($id, true)) {
                     $result->add($rec);
                     $result->count++;
                 }
@@ -787,34 +707,20 @@ class rcube_ldap extends rcube_addressbook
         $rcube = rcube::get_instance();
         $list_fields = $rcube->config->get('contactlist_fields');
 
-        if ($this->prop['vlv_search'] && $this->conn && join(',', (array)$fields) == join(',', $list_fields))
-        {
-            // add general filter to query
-            if (!empty($this->prop['filter']) && empty($this->filter))
-                $this->set_search_set($this->prop['filter']);
-
-            // set VLV controls with encoded search string
-            $this->_vlv_set_controls($this->prop, $this->list_page, $this->page_size, $value);
-
-            $function = $this->_scope2func($this->prop['scope']);
-            $this->ldap_result = @$function($this->conn, $this->base_dn, $this->filter ? $this->filter : '(objectclass=*)',
-                array_values($this->fieldmap), 0, $this->page_size, (int)$this->prop['timelimit']);
-
+        if ($this->prop['vlv_search'] && $this->ready && join(',', (array)$fields) == join(',', $list_fields)) {
             $this->result = new rcube_result_set(0);
 
-            if (!$this->ldap_result) {
-                $this->_debug("S: ".ldap_error($this->conn));
+            $search_suffix = $this->prop['fuzzy_search'] && $mode != 1 ? '*' : '';
+            $ldap_data = $this->ldap->search($this->base_dn, $this->prop['filter'], $this->prop['scope'], $this->prop['attributes'],
+                array('search' => $value . $search_suffix /*, 'sort' => $this->prop['sort'] */));
+            if ($ldap_data === false) {
                 return $this->result;
             }
 
-            $this->_debug("S: ".ldap_count_entries($this->conn, $this->ldap_result)." record(s)");
-
             // get all entries of this page and post-filter those that really match the query
-            $search  = mb_strtolower($value);
-            $entries = ldap_get_entries($this->conn, $this->ldap_result);
-
-            for ($i = 0; $i < $entries['count']; $i++) {
-                $rec = $this->_ldap2result($entries[$i]);
+            $search = mb_strtolower($value);
+            foreach ($ldap_data as $i => $entry) {
+                $rec = $this->_ldap2result($entry);
                 foreach ($fields as $f) {
                     foreach ((array)$rec[$f] as $val) {
                         if ($this->compare_search_value($f, $val, $search, $mode)) {
@@ -840,31 +746,27 @@ class rcube_ldap extends rcube_addressbook
             }
         }
 
-        if ($fields == '*')
-        {
+        if ($fields == '*') {
             // search_fields are required for fulltext search
-            if (empty($this->prop['search_fields']))
-            {
+            if (empty($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']))
-            {
+            if (is_array($this->prop['search_fields'])) {
                 foreach ($this->prop['search_fields'] as $field) {
-                    $filter .= "($field=$wp" . $this->_quote_string($value) . "$ws)";
+                    $filter .= "($field=$wp" . rcube_ldap_generic::quote_string($value) . "$ws)";
                 }
             }
         }
-        else
-        {
+        else {
             foreach ((array)$fields as $idx => $field) {
                 $val = is_array($value) ? $value[$idx] : $value;
                 if ($attrs = $this->_map_field($field)) {
                     if (count($attrs) > 1)
                         $filter .= '(|';
                     foreach ($attrs as $f)
-                        $filter .= "($f=$wp" . $this->_quote_string($val) . "$ws)";
+                        $filter .= "($f=$wp" . rcube_ldap_generic::quote_string($val) . "$ws)";
                     if (count($attrs) > 1)
                         $filter .= ')';
                 }
@@ -875,6 +777,8 @@ class rcube_ldap extends rcube_addressbook
         // add required (non empty) fields filter
         $req_filter = '';
         foreach ((array)$required as $field) {
+            if (in_array($field, (array)$fields))  // required field is already in search filter
+                continue;
             if ($attrs = $this->_map_field($field)) {
                 if (count($attrs) > 1)
                     $req_filter .= '(|';
@@ -897,7 +801,6 @@ class rcube_ldap extends rcube_addressbook
 
         // set filter string and execute search
         $this->set_search_set($filter);
-        $this->_exec_search();
 
         if ($select)
             $this->list_records();
@@ -916,20 +819,21 @@ class rcube_ldap extends rcube_addressbook
     function count()
     {
         $count = 0;
-        if ($this->conn && $this->ldap_result) {
-            $count = $this->vlv_active ? $this->vlv_count : ldap_count_entries($this->conn, $this->ldap_result);
+        if ($this->ldap_result) {
+            $count = $this->ldap_result->count();
         }
         else if ($this->group_id && $this->group_data['dn']) {
             $count = count($this->list_group_members($this->group_data['dn'], true));
         }
-        else if ($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 = $this->prop['filter'];
+        // We have a connection but no result set, attempt to get one.
+        else if ($this->ready) {
+            $prop = $this->group_id ? $this->group_data : $this->prop;
+
+            if (!empty($this->filter)) {  // Use global search filter
+                $prop['filter'] = $this->filter;
             }
 
-            $count = (int) $this->_exec_search(true);
+            $count = $this->ldap->search($prop['base_dn'], $prop['filter'], $prop['scope'], array('dn'), $prop, true);
         }
 
         return new rcube_result_set($count, ($this->list_page-1) * $this->page_size);
@@ -959,28 +863,16 @@ class rcube_ldap extends rcube_addressbook
     {
         $res = $this->result = null;
 
-        if ($this->conn && $dn)
-        {
+        if ($this->ready && $dn) {
             $dn = self::dn_decode($dn);
 
-            $this->_debug("C: Read [dn: $dn] [(objectclass=*)]");
-
-            if ($ldap_result = @ldap_read($this->conn, $dn, '(objectclass=*)', array_values($this->fieldmap))) {
-                $this->_debug("S: OK");
-
-                $entry = ldap_first_entry($this->conn, $ldap_result);
-
-                if ($entry && ($rec = ldap_get_attributes($this->conn, $entry))) {
-                    $rec = array_change_key_case($rec, CASE_LOWER);
-                }
-            }
-            else {
-                $this->_debug("S: ".ldap_error($this->conn));
+            if ($rec = $this->ldap->get_entry($dn)) {
+                $rec = array_change_key_case($rec, CASE_LOWER);
             }
 
             // Use ldap_list to get subentries like country (c) attribute (#1488123)
             if (!empty($rec) && $this->sub_filter) {
-                if ($entries = $this->ldap_list($dn, $this->sub_filter, array_keys($this->prop['sub_fields']))) {
+                if ($entries = $this->ldap->list_entries($dn, $this->sub_filter, array_keys($this->prop['sub_fields']))) {
                     foreach ($entries as $entry) {
                         $lrec = array_change_key_case($entry, CASE_LOWER);
                         $rec  = array_merge($lrec, $rec);
@@ -992,7 +884,7 @@ class rcube_ldap extends rcube_addressbook
                 // Add in the dn for the entry.
                 $rec['dn'] = $dn;
                 $res = $this->_ldap2result($rec);
-                $this->result = new rcube_result_set();
+                $this->result = new rcube_result_set(1);
                 $this->result->add($res);
             }
         }
@@ -1105,7 +997,7 @@ class rcube_ldap extends rcube_addressbook
         }
 
         // Build the new entries DN.
-        $dn = $this->prop['LDAP_rdn'].'='.$this->_quote_string($newentry[$this->prop['LDAP_rdn']], true).','.$this->base_dn;
+        $dn = $this->prop['LDAP_rdn'].'='.rcube_ldap_generic::quote_string($newentry[$this->prop['LDAP_rdn']], true).','.$this->base_dn;
 
         // Remove attributes that need to be added separately (child objects)
         $xfields = array();
@@ -1118,19 +1010,19 @@ class rcube_ldap extends rcube_addressbook
             }
         }
 
-        if (!$this->ldap_add($dn, $newentry)) {
+        if (!$this->ldap->add($dn, $newentry)) {
             $this->set_error(self::ERROR_SAVING, 'errorsaving');
             return false;
         }
 
         foreach ($xfields as $xidx => $xf) {
-            $xdn = $xidx.'='.$this->_quote_string($xf).','.$dn;
+            $xdn = $xidx.'='.rcube_ldap_generic::quote_string($xf).','.$dn;
             $xf = array(
                 $xidx => $xf,
                 'objectClass' => (array) $this->prop['sub_fields'][$xidx],
             );
 
-            $this->ldap_add($xdn, $xf);
+            $this->ldap->add($xdn, $xf);
         }
 
         $dn = self::dn_encode($dn);
@@ -1236,7 +1128,7 @@ class rcube_ldap extends rcube_addressbook
         // Update the entry as required.
         if (!empty($deletedata)) {
             // Delete the fields.
-            if (!$this->ldap_mod_del($dn, $deletedata)) {
+            if (!$this->ldap->mod_del($dn, $deletedata)) {
                 $this->set_error(self::ERROR_SAVING, 'errorsaving');
                 return false;
             }
@@ -1246,17 +1138,17 @@ class rcube_ldap extends rcube_addressbook
             // Handle RDN change
             if ($replacedata[$this->prop['LDAP_rdn']]) {
                 $newdn = $this->prop['LDAP_rdn'].'='
-                    .$this->_quote_string($replacedata[$this->prop['LDAP_rdn']], true)
+                    .rcube_ldap_generic::quote_string($replacedata[$this->prop['LDAP_rdn']], true)
                     .','.$this->base_dn;
                 if ($dn != $newdn) {
                     $newrdn = $this->prop['LDAP_rdn'].'='
-                    .$this->_quote_string($replacedata[$this->prop['LDAP_rdn']], true);
+                    .rcube_ldap_generic::quote_string($replacedata[$this->prop['LDAP_rdn']], true);
                     unset($replacedata[$this->prop['LDAP_rdn']]);
                 }
             }
             // Replace the fields.
             if (!empty($replacedata)) {
-                if (!$this->ldap_mod_replace($dn, $replacedata)) {
+                if (!$this->ldap->mod_replace($dn, $replacedata)) {
                     $this->set_error(self::ERROR_SAVING, 'errorsaving');
                     return false;
                 }
@@ -1272,8 +1164,8 @@ class rcube_ldap extends rcube_addressbook
         // remove sub-entries
         if (!empty($subdeldata)) {
             foreach ($subdeldata as $fld => $val) {
-                $subdn = $fld.'='.$this->_quote_string($val).','.$dn;
-                if (!$this->ldap_delete($subdn)) {
+                $subdn = $fld.'='.rcube_ldap_generic::quote_string($val).','.$dn;
+                if (!$this->ldap->delete($subdn)) {
                     return false;
                 }
             }
@@ -1281,7 +1173,7 @@ class rcube_ldap extends rcube_addressbook
 
         if (!empty($newdata)) {
             // Add the fields.
-            if (!$this->ldap_mod_add($dn, $newdata)) {
+            if (!$this->ldap->mod_add($dn, $newdata)) {
                 $this->set_error(self::ERROR_SAVING, 'errorsaving');
                 return false;
             }
@@ -1289,7 +1181,7 @@ class rcube_ldap extends rcube_addressbook
 
         // Handle RDN change
         if (!empty($newrdn)) {
-            if (!$this->ldap_rename($dn, $newrdn, null, true)) {
+            if (!$this->ldap->rename($dn, $newrdn, null, true)) {
                 $this->set_error(self::ERROR_SAVING, 'errorsaving');
                 return false;
             }
@@ -1300,7 +1192,7 @@ class rcube_ldap extends rcube_addressbook
             // change the group membership of the contact
             if ($this->groups) {
                 $group_ids = $this->get_record_groups($dn);
-                foreach ($group_ids as $group_id)
+                foreach ($group_ids as $group_id => $group_prop)
                 {
                     $this->remove_from_group($group_id, $dn);
                     $this->add_to_group($group_id, $newdn);
@@ -1313,12 +1205,12 @@ class rcube_ldap extends rcube_addressbook
         // add sub-entries
         if (!empty($subnewdata)) {
             foreach ($subnewdata as $fld => $val) {
-                $subdn = $fld.'='.$this->_quote_string($val).','.$dn;
+                $subdn = $fld.'='.rcube_ldap_generic::quote_string($val).','.$dn;
                 $xf = array(
                     $fld => $val,
                     'objectClass' => (array) $this->prop['sub_fields'][$fld],
                 );
-                $this->ldap_add($subdn, $xf);
+                $this->ldap->add($subdn, $xf);
             }
         }
 
@@ -1346,9 +1238,9 @@ class rcube_ldap extends rcube_addressbook
 
             // Need to delete all sub-entries first
             if ($this->sub_filter) {
-                if ($entries = $this->ldap_list($dn, $this->sub_filter)) {
+                if ($entries = $this->ldap->list_entries($dn, $this->sub_filter)) {
                     foreach ($entries as $entry) {
-                        if (!$this->ldap_delete($entry['dn'])) {
+                        if (!$this->ldap->delete($entry['dn'])) {
                             $this->set_error(self::ERROR_SAVING, 'errorsaving');
                             return false;
                         }
@@ -1357,7 +1249,7 @@ class rcube_ldap extends rcube_addressbook
             }
 
             // Delete the record.
-            if (!$this->ldap_delete($dn)) {
+            if (!$this->ldap->delete($dn)) {
                 $this->set_error(self::ERROR_SAVING, 'errorsaving');
                 return false;
             }
@@ -1366,7 +1258,7 @@ class rcube_ldap extends rcube_addressbook
             if ($this->groups) {
                 $dn = self::dn_encode($dn);
                 $group_ids = $this->get_record_groups($dn);
-                foreach ($group_ids as $group_id) {
+                foreach ($group_ids as $group_id => $group_prop) {
                     $this->remove_from_group($group_id, $dn);
                 }
             }
@@ -1381,8 +1273,8 @@ class rcube_ldap extends rcube_addressbook
      */
     function delete_all()
     {
-        //searching for contact entries
-        $dn_list = $this->ldap_list($this->base_dn, $this->prop['filter'] ? $this->prop['filter'] : '(objectclass=*)');
+        // searching for contact entries
+        $dn_list = $this->ldap->list_entries($this->base_dn, $this->prop['filter'] ? $this->prop['filter'] : '(objectclass=*)');
 
         if (!empty($dn_list)) {
             foreach ($dn_list as $idx => $entry) {
@@ -1432,120 +1324,26 @@ class rcube_ldap extends rcube_addressbook
         }
     }
 
-    /**
-     * Execute the LDAP search based on the stored credentials
-     */
-    private function _exec_search($count = false)
-    {
-        if ($this->ready)
-        {
-            $filter = $this->filter ? $this->filter : '(objectclass=*)';
-            $function = $this->_scope2func($this->prop['scope'], $ns_function);
-
-            $this->_debug("C: Search [$filter][dn: $this->base_dn]");
-
-            // when using VLV, we get the total count by...
-            if (!$count && $function != 'ldap_read' && $this->prop['vlv'] && !$this->group_id) {
-                // ...either reading numSubOrdinates attribute
-                if ($this->prop['numsub_filter'] && ($result_count = @$ns_function($this->conn, $this->base_dn, $this->prop['numsub_filter'], array('numSubOrdinates'), 0, 0, 0))) {
-                    $counts = ldap_get_entries($this->conn, $result_count);
-                    for ($this->vlv_count = $j = 0; $j < $counts['count']; $j++)
-                        $this->vlv_count += $counts[$j]['numsubordinates'][0];
-                    $this->_debug("D: total numsubordinates = " . $this->vlv_count);
-                }
-                else if (!function_exists('ldap_parse_virtuallist_control'))  // ...or by fetching all records dn and count them
-                    $this->vlv_count = $this->_exec_search(true);
-
-                $this->vlv_active = $this->_vlv_set_controls($this->prop, $this->list_page, $this->page_size);
-            }
-
-            // only fetch dn for count (should keep the payload low)
-            $attrs = $count ? array('dn') : array_values($this->fieldmap);
-            if ($this->ldap_result = @$function($this->conn, $this->base_dn, $filter,
-                $attrs, 0, (int)$this->prop['sizelimit'], (int)$this->prop['timelimit'])
-            ) {
-                // when running on a patched PHP we can use the extended functions to retrieve the total count from the LDAP search result
-                if ($this->vlv_active && function_exists('ldap_parse_virtuallist_control')) {
-                    if (ldap_parse_result($this->conn, $this->ldap_result,
-                        $errcode, $matcheddn, $errmsg, $referrals, $serverctrls)
-                        && $serverctrls // can be null e.g. in case of adm. limit error
-                    ) {
-                        ldap_parse_virtuallist_control($this->conn, $serverctrls,
-                            $last_offset, $this->vlv_count, $vresult);
-                        $this->_debug("S: VLV result: last_offset=$last_offset; content_count=$this->vlv_count");
-                    }
-                    else {
-                        $this->_debug("S: ".($errmsg ? $errmsg : ldap_error($this->conn)));
-                    }
-                }
-
-                $entries_count = ldap_count_entries($this->conn, $this->ldap_result);
-                $this->_debug("S: $entries_count record(s)");
-
-                return $count ? $entries_count : true;
-            }
-            else {
-                $this->_debug("S: ".ldap_error($this->conn));
-            }
-        }
-
-        return false;
-    }
-
-    /**
-     * Choose the right PHP function according to scope property
-     */
-    private function _scope2func($scope, &$ns_function = null)
-    {
-        switch ($scope) {
-          case 'sub':
-            $function = $ns_function  = 'ldap_search';
-            break;
-          case 'base':
-            $function = $ns_function = 'ldap_read';
-            break;
-          default:
-            $function = 'ldap_list';
-            $ns_function = 'ldap_read';
-            break;
-        }
-
-        return $function;
-    }
-
-    /**
-     * Set server controls for Virtual List View (paginated listing)
-     */
-    private function _vlv_set_controls($prop, $list_page, $page_size, $search = null)
-    {
-        $sort_ctrl = array('oid' => "1.2.840.113556.1.4.473",  'value' => $this->_sort_ber_encode((array)$prop['sort']));
-        $vlv_ctrl  = array('oid' => "2.16.840.1.113730.3.4.9", 'value' => $this->_vlv_ber_encode(($offset = ($list_page-1) * $page_size + 1), $page_size, $search), 'iscritical' => true);
-
-        $sort = (array)$prop['sort'];
-        $this->_debug("C: set controls sort=" . join(' ', unpack('H'.(strlen($sort_ctrl['value'])*2), $sort_ctrl['value'])) . " ($sort[0]);"
-            . " vlv=" . join(' ', (unpack('H'.(strlen($vlv_ctrl['value'])*2), $vlv_ctrl['value']))) . " ($offset/$page_size)");
-
-        if (!ldap_set_option($this->conn, LDAP_OPT_SERVER_CONTROLS, array($sort_ctrl, $vlv_ctrl))) {
-            $this->_debug("S: ".ldap_error($this->conn));
-            $this->set_error(self::ERROR_SEARCH, 'vlvnotsupported');
-            return false;
-        }
-
-        return true;
-    }
-
 
     /**
      * Converts LDAP entry into an array
      */
     private function _ldap2result($rec)
     {
-        $out = array();
+        $out = array('_type' => 'person');
+        $fieldmap = $this->fieldmap;
 
         if ($rec['dn'])
             $out[$this->primary_key] = self::dn_encode($rec['dn']);
 
-        foreach ($this->fieldmap as $rf => $lf)
+        // determine record type
+        if (self::is_group_entry($rec)) {
+            $out['_type'] = 'group';
+            $out['readonly'] = true;
+            $fieldmap['name'] = $this->group_data['name_attr'] ? $this->group_data['name_attr'] : $this->prop['groups']['name_attr'];
+        }
+
+        foreach ($fieldmap as $rf => $lf)
         {
             for ($i=0; $i < $rec[$lf]['count']; $i++) {
                 if (!($value = $rec[$lf][$i]))
@@ -1607,8 +1405,10 @@ class rcube_ldap extends rcube_addressbook
             if (is_array($colprop['serialized'])) {
                foreach ($colprop['serialized'] as $subtype => $delim) {
                   $key = $col.':'.$subtype;
-                  foreach ((array)$save_cols[$key] as $i => $val)
-                     $save_cols[$key][$i] = join($delim, array($val['street'], $val['locality'], $val['zipcode'], $val['country']));
+                  foreach ((array)$save_cols[$key] as $i => $val) {
+                     $values = array($val['street'], $val['locality'], $val['zipcode'], $val['country']);
+                     $save_cols[$key][$i] = count(array_filter($values)) ? join($delim, $values) : null;
+                 }
                }
             }
         }
@@ -1659,6 +1459,16 @@ class rcube_ldap extends rcube_addressbook
         return (isset($aliases[$name]) ? $aliases[$name] : $name) . $suffix;
     }
 
+    /**
+     * Determines whether the given LDAP entry is a group record
+     */
+    private static function is_group_entry($entry)
+    {
+        return array_intersect(
+            array('group', 'groupofnames', 'kolabgroupofnames', 'groupofuniquenames','kolabgroupofuniquenames','groupofurls'),
+            array_map('strtolower', (array)$entry['objectclass'])
+        );
+    }
 
     /**
      * Prints debug info to the log
@@ -1675,55 +1485,27 @@ class rcube_ldap extends rcube_addressbook
      * Activate/deactivate debug mode
      *
      * @param boolean $dbg True if LDAP commands should be logged
-     * @access public
      */
     function set_debug($dbg = true)
     {
         $this->debug = $dbg;
-    }
-
 
-    /**
-     * Quotes attribute value string
-     *
-     * @param string $str Attribute value
-     * @param bool   $dn  True if the attribute is a DN
-     *
-     * @return string Quoted string
-     */
-    private static function _quote_string($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, $replace);
+        if ($this->ldap) {
+            $this->ldap->set_debug($dbg);
+        }
     }
 
 
     /**
      * Setter for the current group
-     * (empty, has to be re-implemented by extending class)
      */
     function set_group($group_id)
     {
-        if ($group_id)
-        {
-            if (($group_cache = $this->cache->get('groups')) === null)
-                $group_cache = $this->_fetch_groups();
-
+        if ($group_id) {
             $this->group_id = $group_id;
-            $this->group_data = $group_cache[$group_id];
+            $this->group_data = $this->get_group_entry($group_id);
         }
-        else
-        {
+        else {
             $this->group_id = 0;
             $this->group_data = null;
         }
@@ -1746,9 +1528,9 @@ class rcube_ldap extends rcube_addressbook
             return array();
 
         // use cached list for searching
-        $this->cache->expunge();
-        if (!$search || ($group_cache = $this->cache->get('groups')) === null)
+        if (!$this->cache || ($group_cache = $this->cache->get('groups')) === null) {
             $group_cache = $this->_fetch_groups();
+        }
 
         $groups = array();
         if ($search) {
@@ -1769,6 +1551,23 @@ class rcube_ldap extends rcube_addressbook
      */
     private function _fetch_groups($vlv_page = 0)
     {
+        // special case: list groups from 'group_filters' config
+        if (!empty($this->prop['group_filters'])) {
+            $groups = array();
+
+            // list regular groups configuration as special filter
+            if (!empty($this->prop['groups']['filter'])) {
+                $id = '__groups__';
+                $groups[$id] = array('ID' => $id, 'name' => rcube_label('groups'), 'virtual' => true) + $this->prop['groups'];
+            }
+
+            foreach ($this->prop['group_filters'] as $id => $prop) {
+                $groups[$id] = $prop + array('ID' => $id, 'name' => ucfirst($id), 'virtual' => true, 'base_dn' => $this->base_dn);
+            }
+
+            return $groups;
+        }
+
         $base_dn = $this->groups_base_dn;
         $filter = $this->prop['groups']['filter'];
         $name_attr = $this->prop['groups']['name_attr'];
@@ -1776,46 +1575,46 @@ class rcube_ldap extends rcube_addressbook
         $sort_attrs = $this->prop['groups']['sort'] ? (array)$this->prop['groups']['sort'] : array($name_attr);
         $sort_attr = $sort_attrs[0];
 
-        $this->_debug("C: Search [$filter][dn: $base_dn]");
+        $ldap = $this->ldap;
 
         // use vlv to list groups
         if ($this->prop['groups']['vlv']) {
             $page_size = 200;
             if (!$this->prop['groups']['sort'])
                 $this->prop['groups']['sort'] = $sort_attrs;
-            $vlv_active = $this->_vlv_set_controls($this->prop['groups'], $vlv_page+1, $page_size);
+
+            $ldap = clone $this->ldap;
+            $ldap->set_config($this->prop['groups']);
+            $ldap->set_vlv_page($vlv_page+1, $page_size);
         }
 
-        $function = $this->_scope2func($this->prop['groups']['scope']);
-        $res = @$function($this->conn, $base_dn, $filter, array_unique(array('dn', 'objectClass', $name_attr, $email_attr, $sort_attr)));
-        if ($res === false)
-        {
-            $this->_debug("S: ".ldap_error($this->conn));
+        $attrs = array_unique(array('dn', 'objectClass', $name_attr, $email_attr, $sort_attr));
+        $ldap_data = $ldap->search($base_dn, $filter, $this->prop['groups']['scope'], $attrs, $this->prop['groups']);
+        if ($ldap_data === false) {
             return array();
         }
 
-        $ldap_data = ldap_get_entries($this->conn, $res);
-        $this->_debug("S: ".ldap_count_entries($this->conn, $res)." record(s)");
-
         $groups = array();
         $group_sortnames = array();
-        $group_count = $ldap_data["count"];
-        for ($i=0; $i < $group_count; $i++)
-        {
-            $group_name = is_array($ldap_data[$i][$name_attr]) ? $ldap_data[$i][$name_attr][0] : $ldap_data[$i][$name_attr];
-            $group_id = self::dn_encode($group_name);
+        $group_count = $ldap_data->count();
+        foreach ($ldap_data as $entry) {
+            if (!$entry['dn'])  // DN is mandatory
+                $entry['dn'] = $ldap_data->get_dn();
+
+            $group_name = is_array($entry[$name_attr]) ? $entry[$name_attr][0] : $entry[$name_attr];
+            $group_id = self::dn_encode($entry['dn']);
             $groups[$group_id]['ID'] = $group_id;
-            $groups[$group_id]['dn'] = $ldap_data[$i]['dn'];
+            $groups[$group_id]['dn'] = $entry['dn'];
             $groups[$group_id]['name'] = $group_name;
-            $groups[$group_id]['member_attr'] = $this->get_group_member_attr($ldap_data[$i]['objectclass']);
+            $groups[$group_id]['member_attr'] = $this->get_group_member_attr($entry['objectclass']);
 
             // list email attributes of a group
-            for ($j=0; $ldap_data[$i][$email_attr] && $j < $ldap_data[$i][$email_attr]['count']; $j++) {
-                if (strpos($ldap_data[$i][$email_attr][$j], '@') > 0)
-                    $groups[$group_id]['email'][] = $ldap_data[$i][$email_attr][$j];
+            for ($j=0; $entry[$email_attr] && $j < $entry[$email_attr]['count']; $j++) {
+                if (strpos($entry[$email_attr][$j], '@') > 0)
+                    $groups[$group_id]['email'][] = $entry[$email_attr][$j];
             }
 
-            $group_sortnames[] = mb_strtolower($ldap_data[$i][$sort_attr][0]);
+            $group_sortnames[] = mb_strtolower($entry[$sort_attr][0]);
         }
 
         // recursive call can exit here
@@ -1823,8 +1622,7 @@ class rcube_ldap extends rcube_addressbook
             return $groups;
 
         // call recursively until we have fetched all groups
-        while ($vlv_active && $group_count == $page_size)
-        {
+        while ($this->prop['groups']['vlv'] && $group_count == $page_size) {
             $next_page = $this->_fetch_groups(++$vlv_page);
             $groups = array_merge($groups, $next_page);
             $group_count = count($next_page);
@@ -1835,12 +1633,48 @@ class rcube_ldap extends rcube_addressbook
             array_multisort($group_sortnames, SORT_ASC, SORT_STRING, $groups);
 
         // cache this
-        $this->cache->set('groups', $groups);
+        if ($this->cache) {
+            $this->cache->set('groups', $groups);
+        }
 
         return $groups;
     }
 
     /**
+     * Fetch a group entry from LDAP and save in local cache
+     */
+    private function get_group_entry($group_id)
+    {
+        if (!$this->cache || ($group_cache = $this->cache->get('groups')) === null) {
+            $group_cache = $this->_fetch_groups();
+        }
+
+        // add group record to cache if it isn't yet there
+        if (!isset($group_cache[$group_id])) {
+            $name_attr = $this->prop['groups']['name_attr'];
+            $dn = self::dn_decode($group_id);
+
+            if ($list = $this->ldap->read_entries($dn, '(objectClass=*)', array('dn','objectClass','member','uniqueMember','memberURL',$name_attr,$this->fieldmap['email']))) {
+                $entry = $list[0];
+                $group_name = is_array($entry[$name_attr]) ? $entry[$name_attr][0] : $entry[$name_attr];
+                $group_cache[$group_id]['ID'] = $group_id;
+                $group_cache[$group_id]['dn'] = $dn;
+                $group_cache[$group_id]['name'] = $group_name;
+                $group_cache[$group_id]['member_attr'] = $this->get_group_member_attr($entry['objectclass']);
+            }
+            else {
+                $group_cache[$group_id] = false;
+            }
+
+            if ($this->cache) {
+                $this->cache->set('groups', $group_cache);
+            }
+        }
+
+        return $group_cache[$group_id];
+    }
+
+    /**
      * Get group properties such as name and email address(es)
      *
      * @param string Group identifier
@@ -1848,10 +1682,7 @@ class rcube_ldap extends rcube_addressbook
      */
     function get_group($group_id)
     {
-        if (($group_cache = $this->cache->get('groups')) === null)
-            $group_cache = $this->_fetch_groups();
-
-        $group_data = $group_cache[$group_id];
+        $group_data = $this->get_group_entry($group_id);
         unset($group_data['dn'], $group_data['member_attr']);
 
         return $group_data;
@@ -1865,9 +1696,8 @@ class rcube_ldap extends rcube_addressbook
      */
     function create_group($group_name)
     {
-        $base_dn = $this->groups_base_dn;
-        $new_dn = "cn=$group_name,$base_dn";
-        $new_gid = self::dn_encode($group_name);
+        $new_dn = 'cn=' . rcube_ldap_generic::quote_string($group_name, true) . ',' . $this->groups_base_dn;
+        $new_gid = self::dn_encode($new_dn);
         $member_attr = $this->get_group_member_attr();
         $name_attr = $this->prop['groups']['name_attr'] ? $this->prop['groups']['name_attr'] : 'cn';
 
@@ -1877,12 +1707,14 @@ class rcube_ldap extends rcube_addressbook
             $member_attr => '',
         );
 
-        if (!$this->ldap_add($new_dn, $new_entry)) {
+        if (!$this->ldap->add($new_dn, $new_entry)) {
             $this->set_error(self::ERROR_SAVING, 'errorsaving');
             return false;
         }
 
-        $this->cache->remove('groups');
+        if ($this->cache) {
+            $this->cache->remove('groups');
+        }
 
         return array('id' => $new_gid, 'name' => $group_name);
     }
@@ -1895,19 +1727,21 @@ class rcube_ldap extends rcube_addressbook
      */
     function delete_group($group_id)
     {
-        if (($group_cache = $this->cache->get('groups')) === null)
+        if (!$this->cache || ($group_cache = $this->cache->get('groups')) === null) {
             $group_cache = $this->_fetch_groups();
+        }
 
-        $base_dn = $this->groups_base_dn;
-        $group_name = $group_cache[$group_id]['name'];
-        $del_dn = "cn=$group_name,$base_dn";
+        $del_dn = $group_cache[$group_id]['dn'];
 
-        if (!$this->ldap_delete($del_dn)) {
+        if (!$this->ldap->delete($del_dn)) {
             $this->set_error(self::ERROR_SAVING, 'errorsaving');
             return false;
         }
 
-        $this->cache->remove('groups');
+        if ($this->cache) {
+            unset($group_cache[$group_id]);
+            $this->cache->set('groups', $group_cache);
+        }
 
         return true;
     }
@@ -1922,21 +1756,22 @@ class rcube_ldap extends rcube_addressbook
      */
     function rename_group($group_id, $new_name, &$new_gid)
     {
-        if (($group_cache = $this->cache->get('groups')) === null)
+        if (!$this->cache || ($group_cache = $this->cache->get('groups')) === null) {
             $group_cache = $this->_fetch_groups();
+        }
 
-        $base_dn = $this->groups_base_dn;
-        $group_name = $group_cache[$group_id]['name'];
-        $old_dn = "cn=$group_name,$base_dn";
-        $new_rdn = "cn=$new_name";
-        $new_gid = self::dn_encode($new_name);
+        $old_dn = $group_cache[$group_id]['dn'];
+        $new_rdn = "cn=" . rcube_ldap_generic::quote_string($new_name, true);
+        $new_gid = self::dn_encode($new_rdn . ',' . $this->groups_base_dn);
 
-        if (!$this->ldap_rename($old_dn, $new_rdn, null, true)) {
+        if (!$this->ldap->rename($old_dn, $new_rdn, null, true)) {
             $this->set_error(self::ERROR_SAVING, 'errorsaving');
             return false;
         }
 
-        $this->cache->remove('groups');
+        if ($this->cache) {
+            $this->cache->remove('groups');
+        }
 
         return $new_name;
     }
@@ -1951,27 +1786,28 @@ class rcube_ldap extends rcube_addressbook
      */
     function add_to_group($group_id, $contact_ids)
     {
-        if (($group_cache = $this->cache->get('groups')) === null)
+        if (!$this->cache || ($group_cache = $this->cache->get('groups')) === null) {
             $group_cache = $this->_fetch_groups();
+        }
 
         if (!is_array($contact_ids))
             $contact_ids = explode(',', $contact_ids);
 
-        $base_dn     = $this->groups_base_dn;
-        $group_name  = $group_cache[$group_id]['name'];
         $member_attr = $group_cache[$group_id]['member_attr'];
-        $group_dn    = "cn=$group_name,$base_dn";
+        $group_dn    = $group_cache[$group_id]['dn'];
         $new_attrs   = array();
 
         foreach ($contact_ids as $id)
             $new_attrs[$member_attr][] = self::dn_decode($id);
 
-        if (!$this->ldap_mod_add($group_dn, $new_attrs)) {
+        if (!$this->ldap->mod_add($group_dn, $new_attrs)) {
             $this->set_error(self::ERROR_SAVING, 'errorsaving');
             return 0;
         }
 
-        $this->cache->remove('groups');
+        if ($this->cache) {
+            $this->cache->remove('groups');
+        }
 
         return count($new_attrs[$member_attr]);
     }
@@ -1986,27 +1822,28 @@ class rcube_ldap extends rcube_addressbook
      */
     function remove_from_group($group_id, $contact_ids)
     {
-        if (($group_cache = $this->cache->get('groups')) === null)
+        if (!$this->cache || ($group_cache = $this->cache->get('groups')) === null) {
             $group_cache = $this->_fetch_groups();
+        }
 
         if (!is_array($contact_ids))
             $contact_ids = explode(',', $contact_ids);
 
-        $base_dn     = $this->groups_base_dn;
-        $group_name  = $group_cache[$group_id]['name'];
         $member_attr = $group_cache[$group_id]['member_attr'];
-        $group_dn    = "cn=$group_name,$base_dn";
-        $del_attrs   = array();
+        $group_dn    = $group_cache[$group_id]['dn'];
+        $del_attrs = array();
 
         foreach ($contact_ids as $id)
             $del_attrs[$member_attr][] = self::dn_decode($id);
 
-        if (!$this->ldap_mod_del($group_dn, $del_attrs)) {
+        if (!$this->ldap->mod_del($group_dn, $del_attrs)) {
             $this->set_error(self::ERROR_SAVING, 'errorsaving');
             return 0;
         }
 
-        $this->cache->remove('groups');
+        if ($this->cache) {
+            $this->cache->remove('groups');
+        }
 
         return count($del_attrs[$member_attr]);
     }
@@ -2033,23 +1870,18 @@ class rcube_ldap extends rcube_addressbook
             $add_filter = "($member_attr=$contact_dn)";
         $filter = strtr("(|(member=$contact_dn)(uniqueMember=$contact_dn)$add_filter)", array('\\' => '\\\\'));
 
-        $this->_debug("C: Search [$filter][dn: $base_dn]");
-
-        $res = @ldap_search($this->conn, $base_dn, $filter, array($name_attr));
-        if ($res === false)
-        {
-            $this->_debug("S: ".ldap_error($this->conn));
+        $ldap_data = $this->ldap->search($base_dn, $filter, 'sub', array('dn', $name_attr));
+        if ($res === false) {
             return array();
         }
-        $ldap_data = ldap_get_entries($this->conn, $res);
-        $this->_debug("S: ".ldap_count_entries($this->conn, $res)." record(s)");
 
         $groups = array();
-        for ($i=0; $i<$ldap_data["count"]; $i++)
-        {
-            $group_name = $ldap_data[$i][$name_attr][0];
-            $group_id = self::dn_encode($group_name);
-            $groups[$group_id] = $group_id;
+        foreach ($ldap_data as $entry) {
+            if (!$entry['dn'])
+                $entry['dn'] = $ldap_data->get_dn();
+            $group_name = $entry[$name_attr][0];
+            $group_id = self::dn_encode($entry['dn']);
+            $groups[$group_id] = array('ID' => $group_id, 'name' => $group_name, 'dn' => $entry['dn']);
         }
         return $groups;
     }
@@ -2092,135 +1924,6 @@ class rcube_ldap extends rcube_addressbook
 
 
     /**
-     * Generate BER encoded string for Virtual List View option
-     *
-     * @param integer List offset (first record)
-     * @param integer Records per page
-     * @return string BER encoded option value
-     */
-    private function _vlv_ber_encode($offset, $rpp, $search = '')
-    {
-        # this string is ber-encoded, php will prefix this value with:
-        # 04 (octet string) and 10 (length of 16 bytes)
-        # the code behind this string is broken down as follows:
-        # 30 = ber sequence with a length of 0e (14) bytes following
-        # 02 = type integer (in two's complement form) with 2 bytes following (beforeCount): 01 00 (ie 0)
-        # 02 = type integer (in two's complement form) with 2 bytes following (afterCount):  01 18 (ie 25-1=24)
-        # a0 = type context-specific/constructed with a length of 06 (6) bytes following
-        # 02 = type integer with 2 bytes following (offset): 01 01 (ie 1)
-        # 02 = type integer with 2 bytes following (contentCount):  01 00
-
-        # whith a search string present:
-        # 81 = type context-specific/constructed with a length of 04 (4) bytes following (the length will change here)
-        # 81 indicates a user string is present where as a a0 indicates just a offset search
-        # 81 = type context-specific/constructed with a length of 06 (6) bytes following
-
-        # the following info was taken from the ISO/IEC 8825-1:2003 x.690 standard re: the
-        # encoding of integer values (note: these values are in
-        # two-complement form so since offset will never be negative bit 8 of the
-        # leftmost octet should never by set to 1):
-        # 8.3.2: If the contents octets of an integer value encoding consist
-        # of more than one octet, then the bits of the first octet (rightmost) and bit 8
-        # of the second (to the left of first octet) octet:
-        # a) shall not all be ones; and
-        # b) shall not all be zero
-
-        if ($search)
-        {
-            $search = preg_replace('/[^-[:alpha:] ,.()0-9]+/', '', $search);
-            $ber_val = self::_string2hex($search);
-            $str = self::_ber_addseq($ber_val, '81');
-        }
-        else
-        {
-            # construct the string from right to left
-            $str = "020100"; # contentCount
-
-            $ber_val = self::_ber_encode_int($offset);  // returns encoded integer value in hex format
-
-            // calculate octet length of $ber_val
-            $str = self::_ber_addseq($ber_val, '02') . $str;
-
-            // now compute length over $str
-            $str = self::_ber_addseq($str, 'a0');
-        }
-
-        // now tack on records per page
-        $str = "020100" . self::_ber_addseq(self::_ber_encode_int($rpp-1), '02') . $str;
-
-        // now tack on sequence identifier and length
-        $str = self::_ber_addseq($str, '30');
-
-        return pack('H'.strlen($str), $str);
-    }
-
-
-    /**
-     * create ber encoding for sort control
-     *
-     * @param array List of cols to sort by
-     * @return string BER encoded option value
-     */
-    private function _sort_ber_encode($sortcols)
-    {
-        $str = '';
-        foreach (array_reverse((array)$sortcols) as $col) {
-            $ber_val = self::_string2hex($col);
-
-            # 30 = ber sequence with a length of octet value
-            # 04 = octet string with a length of the ascii value
-            $oct = self::_ber_addseq($ber_val, '04');
-            $str = self::_ber_addseq($oct, '30') . $str;
-        }
-
-        // now tack on sequence identifier and length
-        $str = self::_ber_addseq($str, '30');
-
-        return pack('H'.strlen($str), $str);
-    }
-
-    /**
-     * Add BER sequence with correct length and the given identifier
-     */
-    private static function _ber_addseq($str, $identifier)
-    {
-        $len = dechex(strlen($str)/2);
-        if (strlen($len) % 2 != 0)
-            $len = '0'.$len;
-
-        return $identifier . $len . $str;
-    }
-
-    /**
-     * Returns BER encoded integer value in hex format
-     */
-    private static function _ber_encode_int($offset)
-    {
-        $val = dechex($offset);
-        $prefix = '';
-
-        // check if bit 8 of high byte is 1
-        if (preg_match('/^[89abcdef]/', $val))
-            $prefix = '00';
-
-        if (strlen($val)%2 != 0)
-            $prefix .= '0';
-
-        return $prefix . $val;
-    }
-
-    /**
-     * Returns ascii string encoded in hex
-     */
-    private static function _string2hex($str)
-    {
-        $hex = '';
-        for ($i=0; $i < strlen($str); $i++)
-            $hex .= dechex(ord($str[$i]));
-        return $hex;
-    }
-
-    /**
      * HTML-safe DN string encoding
      *
      * @param string $str DN string
@@ -2247,130 +1950,4 @@ class rcube_ldap extends rcube_addressbook
         return base64_decode($str);
     }
 
-    /**
-     * Wrapper for ldap_add()
-     */
-    protected function ldap_add($dn, $entry)
-    {
-        $this->_debug("C: Add [dn: $dn]: ".print_r($entry, true));
-
-        $res = ldap_add($this->conn, $dn, $entry);
-        if ($res === false) {
-            $this->_debug("S: ".ldap_error($this->conn));
-            return false;
-        }
-
-        $this->_debug("S: OK");
-        return true;
-    }
-
-    /**
-     * Wrapper for ldap_delete()
-     */
-    protected function ldap_delete($dn)
-    {
-        $this->_debug("C: Delete [dn: $dn]");
-
-        $res = ldap_delete($this->conn, $dn);
-        if ($res === false) {
-            $this->_debug("S: ".ldap_error($this->conn));
-            return false;
-        }
-
-        $this->_debug("S: OK");
-        return true;
-    }
-
-    /**
-     * Wrapper for ldap_mod_replace()
-     */
-    protected function ldap_mod_replace($dn, $entry)
-    {
-        $this->_debug("C: Replace [dn: $dn]: ".print_r($entry, true));
-
-        if (!ldap_mod_replace($this->conn, $dn, $entry)) {
-            $this->_debug("S: ".ldap_error($this->conn));
-            return false;
-        }
-
-        $this->_debug("S: OK");
-        return true;
-    }
-
-    /**
-     * Wrapper for ldap_mod_add()
-     */
-    protected function ldap_mod_add($dn, $entry)
-    {
-        $this->_debug("C: Add [dn: $dn]: ".print_r($entry, true));
-
-        if (!ldap_mod_add($this->conn, $dn, $entry)) {
-            $this->_debug("S: ".ldap_error($this->conn));
-            return false;
-        }
-
-        $this->_debug("S: OK");
-        return true;
-    }
-
-    /**
-     * Wrapper for ldap_mod_del()
-     */
-    protected function ldap_mod_del($dn, $entry)
-    {
-        $this->_debug("C: Delete [dn: $dn]: ".print_r($entry, true));
-
-        if (!ldap_mod_del($this->conn, $dn, $entry)) {
-            $this->_debug("S: ".ldap_error($this->conn));
-            return false;
-        }
-
-        $this->_debug("S: OK");
-        return true;
-    }
-
-    /**
-     * Wrapper for ldap_rename()
-     */
-    protected function ldap_rename($dn, $newrdn, $newparent = null, $deleteoldrdn = true)
-    {
-        $this->_debug("C: Rename [dn: $dn] [dn: $newrdn]");
-
-        if (!ldap_rename($this->conn, $dn, $newrdn, $newparent, $deleteoldrdn)) {
-            $this->_debug("S: ".ldap_error($this->conn));
-            return false;
-        }
-
-        $this->_debug("S: OK");
-        return true;
-    }
-
-    /**
-     * Wrapper for ldap_list()
-     */
-    protected function ldap_list($dn, $filter, $attrs = array(''))
-    {
-        $list = array();
-        $this->_debug("C: List [dn: $dn] [{$filter}]");
-
-        if ($result = ldap_list($this->conn, $dn, $filter, $attrs)) {
-            $list = ldap_get_entries($this->conn, $result);
-
-            if ($list === false) {
-                $this->_debug("S: ".ldap_error($this->conn));
-                return array();
-            }
-
-            $count = $list['count'];
-            unset($list['count']);
-
-            $this->_debug("S: $count record(s)");
-        }
-        else {
-            $this->_debug("S: ".ldap_error($this->conn));
-        }
-
-        return $list;
-    }
-
 }