githubFork/roundcubemail.git

			@@ -5,8 +5,8 @@
			\| Roundcube/rcube_ldap_generic.php \|
			\| \|
			\| This file is part of the Roundcube Webmail client \|
			\| Copyright (C) 2006-2013, The Roundcube Dev Team \|
			\| Copyright (C) 2012-2013, Kolab Systems AG \|
			\| Copyright (C) 2006-2014, The Roundcube Dev Team \|
			\| Copyright (C) 2012-2015, Kolab Systems AG \|
			\| \|
			\| Licensed under the GNU General Public License version 3 or \|
			\| any later version with exceptions for skins & plugins. \|
			@@ -21,459 +21,136 @@
			+-----------------------------------------------------------------------+
			*/


			/*
			LDAP connection properties
			--------------------------

			$prop = array(
			'host' => '<ldap-server-address>',
			// or
			'hosts' => array('directory.verisign.com'),
			'port' => 389,
			'use_tls' => true\|false,
			'ldap_version' => 3, // using LDAPv3
			'auth_method' => '', // SASL authentication method (for proxy auth), e.g. DIGEST-MD5
			'attributes' => array('dn'), // List of attributes to read from the server
			'vlv' => false, // Enable Virtual List View to more efficiently fetch paginated data (if server supports it)
			'config_root_dn' => 'cn=config', // Root DN to read config (e.g. vlv indexes) from
			'numsub_filter' => '(objectClass=organizationalUnit)', // with VLV, we also use numSubOrdinates to query the total number of records. Set this filter to get all numSubOrdinates attributes for counting
			'sizelimit' => '0', // Enables you to limit the count of entries fetched. Setting this to 0 means no limit.
			'timelimit' => '0', // Sets the number of seconds how long is spend on the search. Setting this to 0 means no limit.
			'network_timeout' => 10, // The timeout (in seconds) for connect + bind arrempts. This is only supported in PHP >= 5.3.0 with OpenLDAP 2.x
			'referrals' => true\|false, // Sets the LDAP_OPT_REFERRALS option. Mostly used in multi-domain Active Directory setups
			);
			*/

			/**
			* Model class to access an LDAP directories
			*
			* @package Framework
			* @subpackage LDAP
			*/
			class rcube_ldap_generic
			class rcube_ldap_generic extends Net_LDAP3
			{
			const UPDATE_MOD_ADD = 1;
			const UPDATE_MOD_DELETE = 2;
			const UPDATE_MOD_REPLACE = 4;
			const UPDATE_MOD_FULL = 7;

			public $conn;
			public $vlv_active = false;

			/** private properties */
			protected $cache = null;
			protected $config = array();
			protected $attributes = array('dn');
			protected $entries = null;
			protected $result = null;
			protected $debug = false;
			protected $list_page = 1;
			protected $page_size = 10;
			protected $vlv_config = null;
			protected $error;


			/**
			* Object constructor
			*
			* @param array $p LDAP connection properties
			*/
			function __construct($p)
			function __construct($config = null)
			{
			$this->config = $p;
			parent::__construct($config);

			if (is_array($p['attributes']))
			$this->attributes = $p['attributes'];

			if (!is_array($p['hosts']) && !empty($p['host']))
			$this->config['hosts'] = array($p['host']);
			$this->config_set('log_hook', array($this, 'log'));
			}

			/**
			* Activate/deactivate debug mode
			*
			* @param boolean $dbg True if LDAP commands should be logged
			* Establish a connection to the LDAP server
			*/
			public function set_debug($dbg = true)
			{
			$this->debug = $dbg;
			}

			/**
			* Set connection options
			*
			* @param mixed $opt Option name as string or hash array with multiple options
			* @param mixed $val Option value
			*/
			public function set_config($opt, $val = null)
			{
			if (is_array($opt))
			$this->config = array_merge($this->config, $opt);
			else
			$this->config[$opt] = $value;
			}

			/**
			* Enable caching by passing an instance of rcube_cache to be used by this object
			*
			* @param object rcube_cache Instance or False to disable caching
			*/
			public function set_cache($cache_engine)
			{
			$this->cache = $cache_engine;
			}

			/**
			* Set properties for VLV-based paging
			*
			* @param number $page Page number to list (starting at 1)
			* @param number $size Number of entries to display on one page
			*/
			public function set_vlv_page($page, $size = 10)
			{
			$this->list_page = $page;
			$this->page_size = $size;
			}

			/**
			* Establish a connection to the LDAP server
			*/
			public function connect($host = null)
			{
			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);
			return false;
			}
			// Net_LDAP3 does not support IDNA yet
			// also parse_host() here is very Roundcube specific
			$host = rcube_utils::idn_to_ascii(rcube_utils::parse_host($host));

			if (is_resource($this->conn) && $this->config['host'] == $host)
			return true;

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

			// iterate over hosts if none specified
			if (!$host) {
			if (!is_array($this->config['hosts']))
			$this->config['hosts'] = array($this->config['hosts']);

			foreach ($this->config['hosts'] as $host) {
			if ($this->connect($host)) {
			return true;
			}
			}

			return false;
			}

			// open connection to the given $host
			$host = rcube_utils::idn_to_ascii(rcube_utils::parse_host($host));
			$hostname = $host . ($this->config['port'] ? ':'.$this->config['port'] : '');

			$this->_debug("C: Connect to $hostname [{$this->config['name']}]");

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

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

			ldap_set_option($lc, LDAP_OPT_PROTOCOL_VERSION, $this->config['ldap_version']);
			$this->config['host'] = $host;
			$this->conn = $lc;

			if (!empty($this->config['network_timeout']))
			ldap_set_option($lc, LDAP_OPT_NETWORK_TIMEOUT, $this->config['network_timeout']);

			if (isset($this->config['referrals']))
			ldap_set_option($lc, LDAP_OPT_REFERRALS, $this->config['referrals']);
			}
			else {
			$this->_debug("S: NOT OK");
			}

			if (!is_resource($this->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);
			return false;
			}

			return true;
			}

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

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

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

			$this->_debug("C: SASL 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));

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

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

			$this->_debug("C: Bind $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;
			}

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

			/**
			* Return the last result set
			*
			* @return object rcube_ldap_result Result object
			*/
			function get_result()
			{
			return $this->result;
			return parent::connect($host);
			}

			/**
			* Get a specific LDAP entry, identified by its DN
			*
			* @param string $dn Record identifier
			* @return array Hash array
			*
			* @return array Hash array
			*/
			function get_entry($dn)
			{
			$rec = null;

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

			if ($ldap_result = @ldap_read($this->conn, $dn, '(objectclass=*)', $this->attributes)) {
			$this->_debug("S: OK");

			if ($entry = ldap_first_entry($this->conn, $ldap_result)) {
			$rec = ldap_get_attributes($this->conn, $entry);
			}
			}
			else {
			$this->_debug("S: ".ldap_error($this->conn));
			}

			if (!empty($rec)) {
			$rec['dn'] = $dn; // Add in the dn for the entry.
			}
			}

			return $rec;
			return parent::get_entry($dn, $this->attributes);
			}

			/**
			* Execute the LDAP search based on the stored credentials
			*
			* @param string $base_dn The base DN to query
			* @param string $filter The LDAP filter for search
			* @param string $scope The LDAP scope (list\|sub\|base)
			* @param array $attrs List of entry attributes to read
			* @param array $prop Hash array with query configuration properties:
			* - sort: array of sort attributes (has to be in sync with the VLV index)
			* - search: search string used for VLV controls
			* @param boolean $count_only Set to true if only entry count is requested
			*
			* @return mixed rcube_ldap_result object or number of entries (if count_only=true) or false on error
			* Prints debug/error info to the log
			*/
			public function search($base_dn, $filter = '', $scope = 'sub', $attrs = array('dn'), $prop = array(), $count_only = false)
			public function log($level, $msg)
			{
			if (!$this->conn) {
			return false;
			}
			$msg = implode("\n", $msg);

			if (empty($filter)) {
			$filter = '(objectclass=*)';
			}

			$this->_debug("C: Search $base_dn for $filter");

			$function = self::scope2func($scope, $ns_function);

			// find available VLV index for this query
			if (!$count_only && ($vlv_sort = $this->_find_vlv($base_dn, $filter, $scope, $prop['sort']))) {
			// when using VLV, we get the total count by...
			// ...either reading numSubOrdinates attribute
			if (($sub_filter = $this->config['numsub_filter']) &&
			($result_count = @$ns_function($this->conn, $base_dn, $sub_filter, array('numSubOrdinates'), 0, 0, 0))
			) {
			$counts = ldap_get_entries($this->conn, $result_count);
			for ($vlv_count = $j = 0; $j < $counts['count']; $j++)
			$vlv_count += $counts[$j]['numsubordinates'][0];
			$this->_debug("D: total numsubordinates = " . $vlv_count);
			switch ($level) {
			case LOG_DEBUG:
			case LOG_INFO:
			case LOG_NOTICE:
			if ($this->config['debug']) {
			rcube::write_log('ldap', $msg);
			}
			// ...or by fetching all records dn and count them
			else if (!function_exists('ldap_parse_virtuallist_control')) {
			$vlv_count = $this->search($base_dn, $filter, $scope, array('dn'), $prop, true);
			}
			break;

			$this->vlv_active = $this->_vlv_set_controls($vlv_sort, $this->list_page, $this->page_size, $prop['search']);
			case LOG_EMERGE:
			case LOG_ALERT:
			case LOG_CRIT:
			rcube::raise_error($msg, true, true);
			break;

			case LOG_ERR:
			case LOG_WARNING:
			$this->error = $msg;
			rcube::raise_error($msg, true, false);
			break;
			}
			else {
			$this->vlv_active = false;
			}

			// only fetch dn for count (should keep the payload low)
			if ($ldap_result = @$function($this->conn, $base_dn, $filter,
			$attrs, 0, (int)$this->config['sizelimit'], (int)$this->config['timelimit'])
			) {
			// when running on a patched PHP we can use the extended functions
			// to retrieve the total count from the LDAP search result
			if ($this->vlv_active && function_exists('ldap_parse_virtuallist_control')) {
			if (ldap_parse_result($this->conn, $ldap_result, $errcode, $matcheddn, $errmsg, $referrals, $serverctrls)) {
			ldap_parse_virtuallist_control($this->conn, $serverctrls, $last_offset, $vlv_count, $vresult);
			$this->_debug("S: VLV result: last_offset=$last_offset; content_count=$vlv_count");
			}
			else {
			$this->_debug("S: ".($errmsg ? $errmsg : ldap_error($this->conn)));
			}
			}
			else if ($this->debug) {
			$this->_debug("S: ".ldap_count_entries($this->conn, $ldap_result)." record(s) found");
			}

			$this->result = new rcube_ldap_result($this->conn, $ldap_result, $base_dn, $filter, $vlv_count);

			return $count_only ? $this->result->count() : $this->result;
			}
			else {
			$this->_debug("S: ".ldap_error($this->conn));
			}

			return false;
			}

			/**
			* Modify an LDAP entry on the server
			* Returns the last LDAP error occurred
			*
			* @param string $dn Entry DN
			* @param array $params Hash array of entry attributes
			* @param int $mode Update mode (UPDATE_MOD_ADD \| UPDATE_MOD_DELETE \| UPDATE_MOD_REPLACE)
			* @return mixed Error message string or null if no error occured
			*/
			public function modify($dn, $parms, $mode = 255)
			function get_error()
			{
			// TODO: implement this

			return false;
			return $this->error;
			}

			/**
			* Wrapper for ldap_add()
			*
			* @see ldap_add()
			* @deprecated
			*/
			public function set_debug($dbg = true)
			{
			$this->config['debug'] = (bool) $dbg;
			}

			/**
			* @deprecated
			*/
			public function set_cache($cache_engine)
			{
			$this->config['cache'] = $cache_engine;
			}

			/**
			* @deprecated
			*/
			public static function scope2func($scope, &$ns_function = null)
			{
			return self::scope_to_function($scope, $ns_function);
			}

			/**
			* @deprecated
			*/
			public function set_config($opt, $val = null)
			{
			$this->config_set($opt, $val);
			}

			/**
			* @deprecated
			*/
			public function add($dn, $entry)
			{
			$this->_debug("C: Add $dn: ".print_r($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;
			return $this->add_entry($dn, $entry);
			}

			/**
			* Wrapper for ldap_delete()
			*
			* @see ldap_delete()
			* @deprecated
			*/
			public function delete($dn)
			{
			$this->_debug("C: Delete $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;
			return $this->delete_entry($dn);
			}

			/**
			@@ -486,7 +163,7 @@
			$this->_debug("C: Replace $dn: ".print_r($entry, true));

			if (!ldap_mod_replace($this->conn, $dn, $entry)) {
			$this->_debug("S: ".ldap_error($this->conn));
			$this->_error("ldap_mod_replace() failed with " . ldap_error($this->conn));
			return false;
			}

			@@ -504,7 +181,7 @@
			$this->_debug("C: Add $dn: ".print_r($entry, true));

			if (!ldap_mod_add($this->conn, $dn, $entry)) {
			$this->_debug("S: ".ldap_error($this->conn));
			$this->_error("ldap_mod_add() failed with " . ldap_error($this->conn));
			return false;
			}

			@@ -522,7 +199,7 @@
			$this->_debug("C: Delete $dn: ".print_r($entry, true));

			if (!ldap_mod_del($this->conn, $dn, $entry)) {
			$this->_debug("S: ".ldap_error($this->conn));
			$this->_error("ldap_mod_del() failed with " . ldap_error($this->conn));
			return false;
			}

			@@ -540,7 +217,7 @@
			$this->_debug("C: Rename $dn to $newrdn");

			if (!ldap_rename($this->conn, $dn, $newrdn, $newparent, $deleteoldrdn)) {
			$this->_debug("S: ".ldap_error($this->conn));
			$this->_error("ldap_rename() failed with " . ldap_error($this->conn));
			return false;
			}

			@@ -563,7 +240,7 @@
			$list = ldap_get_entries($this->conn, $result);

			if ($list === false) {
			$this->_debug("S: ".ldap_error($this->conn));
			$this->_error("ldap_get_entries() failed with " . ldap_error($this->conn));
			return array();
			}

			@@ -573,7 +250,7 @@
			$this->_debug("S: $count record(s)");
			}
			else {
			$this->_debug("S: ".ldap_error($this->conn));
			$this->_error("ldap_list() failed with " . ldap_error($this->conn));
			}

			return $list;
			@@ -590,12 +267,9 @@
			$this->_debug("C: Read $dn [{$filter}]");

			if ($this->conn && $dn) {
			if (!$attributes)
			$attributes = $this->attributes;

			$result = @ldap_read($this->conn, $dn, $filter, $attributes, 0, (int)$this->config['sizelimit'], (int)$this->config['timelimit']);
			if ($result === false) {
			$this->_debug("S: ".ldap_error($this->conn));
			$this->_error("ldap_read() failed with " . ldap_error($this->conn));
			return false;
			}

			@@ -607,100 +281,20 @@
			}

			/**
			* Choose the right PHP function according to scope property
			*
			* @param string $scope The LDAP scope (sub\|base\|list)
			* @param string $ns_function Function to be used for numSubOrdinates queries
			* @return string PHP function to be used to query directory
			*/
			public static function scope2func($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;
			}

			/**
			* Convert the given scope integer value to a string representation
			*/
			public static function scopeint2str($scope)
			{
			switch ($scope) {
			case 2: return 'sub';
			case 1: return 'one';
			case 0: return 'base';
			default: $this->_debug("Scope $scope is not a valid scope integer");
			}

			return '';
			}

			/**
			* Escapes the given value according to RFC 2254 so that it can be safely used in LDAP filters.
			*
			* @param string $val Value to quote
			* @return string The escaped value
			*/
			public static function escape_value($val)
			{
			return strtr($str, array('*'=>'\2a', '('=>'\28', ')'=>'\29',
			'\\'=>'\5c', '/'=>'\2f'));
			}

			/**
			* Escapes a DN value according to RFC 2253
			*
			* @param string $dn DN value o quote
			* @return string The escaped value
			*/
			public static function escape_dn($dn)
			{
			return strtr($str, array(','=>'\2c', '='=>'\3d', '+'=>'\2b',
			'<'=>'\3c', '>'=>'\3e', ';'=>'\3b', '\\'=>'\5c',
			'"'=>'\22', '#'=>'\23'));
			}

			/**
			* Normalize a LDAP result by converting entry attributes arrays into single values
			*
			* @param array $result LDAP result set fetched with ldap_get_entries()
			* @return array Hash array with normalized entries, indexed by their DNs
			*/
			public static function normalize_result($result)
			{
			if (!is_array($result)) {
			return array();
			}

			$entries = array();
			for ($i = 0; $i < $result['count']; $i++) {
			$key = $result[$i]['dn'] ? $result[$i]['dn'] : $i;
			$entries[$key] = self::normalize_entry($result[$i]);
			}

			return $entries;
			}

			/**
			* Turn an LDAP entry into a regular PHP array with attributes as keys.
			*
			* @param array $entry Attributes array as retrieved from ldap_get_attributes() or ldap_get_entries()
			* @return array Hash array with attributes as keys
			*
			* @return array Hash array with attributes as keys
			*/
			public static function normalize_entry($entry)
			{
			if (!isset($entry['count'])) {
			return $entry;
			}

			$rec = array();

			for ($i=0; $i < $entry['count']; $i++) {
			$attr = $entry[$i];
			if ($entry[$attr]['count'] == 1) {
			@@ -724,326 +318,46 @@
			}

			/**
			* Set server controls for Virtual List View (paginated listing)
			* Compose an LDAP filter string matching all words from the search string
			* in the given list of attributes.
			*
			* @param string $value Search value
			* @param mixed $attrs List of LDAP attributes to search
			* @param int $mode Matching mode:
			* 0 - partial (abc),
			* 1 - strict (=),
			* 2 - prefix (abc*)
			* @return string LDAP filter
			*/
			private function _vlv_set_controls($sort, $list_page, $page_size, $search = null)
			public static function fulltext_search_filter($value, $attributes, $mode = 1)
			{
			$sort_ctrl = array('oid' => "1.2.840.113556.1.4.473", 'value' => self::_sort_ber_encode((array)$sort));
			$vlv_ctrl = array('oid' => "2.16.840.1.113730.3.4.9", 'value' => self::_vlv_ber_encode(($offset = ($list_page-1) * $page_size + 1), $page_size, $search), 'iscritical' => true);

			$this->_debug("C: Set controls sort=" . join(' ', unpack('H'.(strlen($sort_ctrl['value'])*2), $sort_ctrl['value'])) . " ($sort[0]);"
			. " vlv=" . join(' ', (unpack('H'.(strlen($vlv_ctrl['value'])*2), $vlv_ctrl['value']))) . " ($offset/$page_size; $search)");

			if (!ldap_set_option($this->conn, LDAP_OPT_SERVER_CONTROLS, array($sort_ctrl, $vlv_ctrl))) {
			$this->_debug("S: ".ldap_error($this->conn));
			$this->set_error(self::ERROR_SEARCH, 'vlvnotsupported');
			return false;
			if (empty($attributes)) {
			$attributes = array('cn');
			}

			return true;
			}
			$groups = array();
			$value = str_replace('*', '', $value);
			$words = $mode == 0 ? rcube_utils::tokenize_string($value, 1) : array($value);

			/**
			* Returns unified attribute name (resolving aliases)
			*/
			private static function _attr_name($namev)
			{
			// list of known attribute aliases
			static $aliases = array(
			'gn' => 'givenname',
			'rfc822mailbox' => 'email',
			'userid' => 'uid',
			'emailaddress' => 'email',
			'pkcs9email' => 'email',
			);

			list($name, $limit) = explode(':', $namev, 2);
			$suffix = $limit ? ':'.$limit : '';

			return (isset($aliases[$name]) ? $aliases[$name] : $name) . $suffix;
			}

			/**
			* Quotes attribute value string
			*
			* @param string $str Attribute value
			* @param bool $dn True if the attribute is a DN
			*
			* @return string Quoted string
			*/
			public static function quote_string($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);
			}

			/**
			* Prints debug info to the log
			*/
			private function _debug($str)
			{
			if ($this->debug && class_exists('rcube')) {
			rcube::write_log('ldap', $str);
			// set wildcards
			$wp = $ws = '';
			if ($mode != 1) {
			$ws = '*';
			$wp = !$mode ? '*' : '';
			}
			}


			/*************** Virtual List View (VLV) related utility functions ************** */

			/**
			* Return the search string value to be used in VLV controls
			*/
			private function _vlv_search($sort, $search)
			{
			foreach ($search as $attr => $value) {
			if (!in_array(strtolower($attr), $sort)) {
			$this->_debug("d: Cannot use VLV search using attribute not indexed: $attr (not in " . var_export($sort, true) . ")");
			return null;
			} else {
			return $value;
			// search each word in all listed attributes
			foreach ($words as $word) {
			$parts = array();
			foreach ($attributes as $attr) {
			$parts[] = "($attr=$wp" . self::quote_string($word) . "$ws)";
			}
			$groups[] = '(\|' . join('', $parts) . ')';
			}

			return count($groups) > 1 ? '(&' . join('', $groups) . ')' : join('', $groups);
			}

			/**
			* Find a VLV index matching the given query attributes
			*
			* @return string Sort attribute or False if no match
			*/
			private function _find_vlv($base_dn, $filter, $scope, $sort_attrs = null)
			{
			if (!$this->config['vlv'] \|\| $scope == 'base') {
			return false;
			}

			// get vlv config
			$vlv_config = $this->_read_vlv_config();

			if ($vlv = $vlv_config[$base_dn]) {
			$this->_debug("D: Found a VLV for $base_dn");

			if ($vlv['filter'] == strtolower($filter) \|\| stripos($filter, '(&'.$vlv['filter'].'(') === 0) {
			$this->_debug("D: Filter matches");
			if ($vlv['scope'] == $scope) {
			// Not passing any sort attributes means you don't care
			if (empty($sort_attrs) \|\| in_array($sort_attrs, $vlv['sort'])) {
			return $vlv['sort'][0];
			}
			}
			else {
			$this->_debug("D: Scope does not match");
			}
			}
			else {
			$this->_debug("D: Filter does not match");
			}
			}
			else {
			$this->_debug("D: No VLV for $base_dn");
			}

			return false;
			}

			/**
			* Return VLV indexes and searches including necessary configuration
			* details.
			*/
			private function _read_vlv_config()
			{
			if (empty($this->config['vlv']) \|\| empty($this->config['config_root_dn'])) {
			return array();
			}
			// return hard-coded VLV config
			else if (is_array($this->config['vlv'])) {
			return $this->config['vlv'];
			}

			// return cached result
			if (is_array($this->vlv_config)) {
			return $this->vlv_config;
			}

			if ($this->cache && ($cached_config = $this->cache->get('vlvconfig'))) {
			$this->vlv_config = $cached_config;
			return $this->vlv_config;
			}

			$this->vlv_config = array();

			$ldap_result = ldap_search($this->conn, $this->config['config_root_dn'], '(objectclass=vlvsearch)', array('*'), 0, 0, 0);
			$vlv_searches = new rcube_ldap_result($this->conn, $ldap_result, $this->config['config_root_dn'], '(objectclass=vlvsearch)');

			if ($vlv_searches->count() < 1) {
			$this->_debug("D: Empty result from search for '(objectclass=vlvsearch)' on '$config_root_dn'");
			return array();
			}

			foreach ($vlv_searches->entries(true) as $vlv_search_dn => $vlv_search_attrs) {
			// Multiple indexes may exist
			$ldap_result = ldap_search($this->conn, $vlv_search_dn, '(objectclass=vlvindex)', array('*'), 0, 0, 0);
			$vlv_indexes = new rcube_ldap_result($this->conn, $ldap_result, $vlv_search_dn, '(objectclass=vlvindex)');

			// Reset this one for each VLV search.
			$_vlv_sort = array();
			foreach ($vlv_indexes->entries(true) as $vlv_index_dn => $vlv_index_attrs) {
			$_vlv_sort[] = explode(' ', $vlv_index_attrs['vlvsort']);
			}

			$this->vlv_config[$vlv_search_attrs['vlvbase']] = array(
			'scope' => self::scopeint2str($vlv_search_attrs['vlvscope']),
			'filter' => strtolower($vlv_search_attrs['vlvfilter']),
			'sort' => $_vlv_sort,
			);
			}

			// cache this
			if ($this->cache)
			$this->cache->set('vlvconfig', $this->vlv_config);

			$this->_debug("D: Refreshed VLV config: " . var_export($this->vlv_config, true));

			return $this->vlv_config;
			}

			/**
			* 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 static 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

			with 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 static 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;
			}

			}

			// for backward compat.
			class rcube_ldap_result extends Net_LDAP3_Result {}