web/lib/Zend/Ldap.php
changeset 64 162c1de6545a
parent 19 1c2f13fd785c
child 68 ecaf28ffe26e
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/web/lib/Zend/Ldap.php	Fri Mar 11 15:05:35 2011 +0100
@@ -0,0 +1,1594 @@
+<?php
+
+/**
+ * Zend Framework
+ *
+ * LICENSE
+ *
+ * This source file is subject to the new BSD license that is bundled
+ * with this package in the file LICENSE.txt.
+ * It is also available through the world-wide-web at this URL:
+ * http://framework.zend.com/license/new-bsd
+ * If you did not receive a copy of the license and are unable to
+ * obtain it through the world-wide-web, please send an email
+ * to license@zend.com so we can send you a copy immediately.
+ *
+ * @category   Zend
+ * @package    Zend_Ldap
+ * @copyright  Copyright (c) 2005-2010 Zend Technologies USA Inc. (http://www.zend.com)
+ * @license    http://framework.zend.com/license/new-bsd     New BSD License
+ * @version    $Id: Ldap.php 22996 2010-09-22 17:01:46Z sgehrig $
+ */
+
+/**
+ * @category   Zend
+ * @package    Zend_Ldap
+ * @copyright  Copyright (c) 2005-2010 Zend Technologies USA Inc. (http://www.zend.com)
+ * @license    http://framework.zend.com/license/new-bsd     New BSD License
+ */
+class Zend_Ldap
+{
+    const SEARCH_SCOPE_SUB  = 1;
+    const SEARCH_SCOPE_ONE  = 2;
+    const SEARCH_SCOPE_BASE = 3;
+
+    const ACCTNAME_FORM_DN        = 1;
+    const ACCTNAME_FORM_USERNAME  = 2;
+    const ACCTNAME_FORM_BACKSLASH = 3;
+    const ACCTNAME_FORM_PRINCIPAL = 4;
+
+    /**
+     * String used with ldap_connect for error handling purposes.
+     *
+     * @var string
+     */
+    private $_connectString;
+
+    /**
+     * The options used in connecting, binding, etc.
+     *
+     * @var array
+     */
+    protected $_options = null;
+
+    /**
+     * The raw LDAP extension resource.
+     *
+     * @var resource
+     */
+    protected $_resource = null;
+
+    /**
+     * FALSE if no user is bound to the LDAP resource
+     * NULL if there has been an anonymous bind
+     * username of the currently bound user
+     *
+     * @var boolean|null|string
+     */
+    protected $_boundUser = false;
+
+    /**
+     * Caches the RootDSE
+     *
+     * @var Zend_Ldap_Node
+     */
+    protected $_rootDse = null;
+
+    /**
+     * Caches the schema
+     *
+     * @var Zend_Ldap_Node
+     */
+    protected $_schema = null;
+
+    /**
+     * @deprecated will be removed, use {@see Zend_Ldap_Filter_Abstract::escapeValue()}
+     * @param  string $str The string to escape.
+     * @return string The escaped string
+     */
+    public static function filterEscape($str)
+    {
+        /**
+         * @see Zend_Ldap_Filter_Abstract
+         */
+        require_once 'Zend/Ldap/Filter/Abstract.php';
+        return Zend_Ldap_Filter_Abstract::escapeValue($str);
+    }
+
+    /**
+     * @deprecated will be removed, use {@see Zend_Ldap_Dn::checkDn()}
+     * @param  string $dn   The DN to parse
+     * @param  array  $keys An optional array to receive DN keys (e.g. CN, OU, DC, ...)
+     * @param  array  $vals An optional array to receive DN values
+     * @return boolean True if the DN was successfully parsed or false if the string is
+     * not a valid DN.
+     */
+    public static function explodeDn($dn, array &$keys = null, array &$vals = null)
+    {
+        /**
+         * @see Zend_Ldap_Dn
+         */
+        require_once 'Zend/Ldap/Dn.php';
+        return Zend_Ldap_Dn::checkDn($dn, $keys, $vals);
+    }
+
+    /**
+     * Constructor.
+     *
+     * @param  array|Zend_Config $options Options used in connecting, binding, etc.
+     * @return void
+     * @throws Zend_Ldap_Exception if ext/ldap is not installed
+     */
+    public function __construct($options = array())
+    {
+        if (!extension_loaded('ldap')) {
+            /**
+             * @see Zend_Ldap_Exception
+             */
+            require_once 'Zend/Ldap/Exception.php';
+            throw new Zend_Ldap_Exception(null, 'LDAP extension not loaded',
+                Zend_Ldap_Exception::LDAP_X_EXTENSION_NOT_LOADED);
+        }
+        $this->setOptions($options);
+    }
+
+    /**
+     * Destructor.
+     *
+     * @return void
+     */
+    public function __destruct()
+    {
+        $this->disconnect();
+    }
+
+    /**
+     * @return resource The raw LDAP extension resource.
+     */
+    public function getResource()
+    {
+        if (!is_resource($this->_resource) || $this->_boundUser === false) {
+            $this->bind();
+        }
+        return $this->_resource;
+    }
+
+    /**
+     * Return the LDAP error number of the last LDAP command
+     *
+     * @return int
+     */
+    public function getLastErrorCode()
+    {
+        $ret = @ldap_get_option($this->_resource, LDAP_OPT_ERROR_NUMBER, $err);
+        if ($ret === true) {
+            if ($err <= -1 && $err >= -17) {
+                /**
+                 * @see Zend_Ldap_Exception
+                 */
+                require_once 'Zend/Ldap/Exception.php';
+                /* For some reason draft-ietf-ldapext-ldap-c-api-xx.txt error
+                 * codes in OpenLDAP are negative values from -1 to -17.
+                 */
+                $err = Zend_Ldap_Exception::LDAP_SERVER_DOWN + (-$err - 1);
+            }
+            return $err;
+        }
+        return 0;
+    }
+
+    /**
+     * Return the LDAP error message of the last LDAP command
+     *
+     * @param  int   $errorCode
+     * @param  array $errorMessages
+     * @return string
+     */
+    public function getLastError(&$errorCode = null, array &$errorMessages = null)
+    {
+        $errorCode = $this->getLastErrorCode();
+        $errorMessages = array();
+
+        /* The various error retrieval functions can return
+         * different things so we just try to collect what we
+         * can and eliminate dupes.
+         */
+        $estr1 = @ldap_error($this->_resource);
+        if ($errorCode !== 0 && $estr1 === 'Success') {
+            $estr1 = @ldap_err2str($errorCode);
+        }
+        if (!empty($estr1)) {
+            $errorMessages[] = $estr1;
+        }
+
+        @ldap_get_option($this->_resource, LDAP_OPT_ERROR_STRING, $estr2);
+        if (!empty($estr2) && !in_array($estr2, $errorMessages)) {
+            $errorMessages[] = $estr2;
+        }
+
+        $message = '';
+        if ($errorCode > 0) {
+            $message = '0x' . dechex($errorCode) . ' ';
+        } else {
+            $message = '';
+        }
+        if (count($errorMessages) > 0) {
+            $message .= '(' . implode('; ', $errorMessages) . ')';
+        } else {
+            $message .= '(no error message from LDAP)';
+        }
+        return $message;
+    }
+
+    /**
+     * Get the currently bound user
+     *
+     * FALSE if no user is bound to the LDAP resource
+     * NULL if there has been an anonymous bind
+     * username of the currently bound user
+     *
+     * @return false|null|string
+     */
+    public function getBoundUser()
+    {
+        return $this->_boundUser;
+    }
+
+    /**
+     * Sets the options used in connecting, binding, etc.
+     *
+     * Valid option keys:
+     *  host
+     *  port
+     *  useSsl
+     *  username
+     *  password
+     *  bindRequiresDn
+     *  baseDn
+     *  accountCanonicalForm
+     *  accountDomainName
+     *  accountDomainNameShort
+     *  accountFilterFormat
+     *  allowEmptyPassword
+     *  useStartTls
+     *  optRefferals
+     *  tryUsernameSplit
+     *
+     * @param  array|Zend_Config $options Options used in connecting, binding, etc.
+     * @return Zend_Ldap Provides a fluent interface
+     * @throws Zend_Ldap_Exception
+     */
+    public function setOptions($options)
+    {
+        if ($options instanceof Zend_Config) {
+            $options = $options->toArray();
+        }
+
+        $permittedOptions = array(
+            'host'                   => null,
+            'port'                   => 0,
+            'useSsl'                 => false,
+            'username'               => null,
+            'password'               => null,
+            'bindRequiresDn'         => false,
+            'baseDn'                 => null,
+            'accountCanonicalForm'   => null,
+            'accountDomainName'      => null,
+            'accountDomainNameShort' => null,
+            'accountFilterFormat'    => null,
+            'allowEmptyPassword'     => false,
+            'useStartTls'            => false,
+            'optReferrals'           => false,
+            'tryUsernameSplit'       => true,
+        );
+
+        foreach ($permittedOptions as $key => $val) {
+            if (array_key_exists($key, $options)) {
+                $val = $options[$key];
+                unset($options[$key]);
+                /* Enforce typing. This eliminates issues like Zend_Config_Ini
+                 * returning '1' as a string (ZF-3163).
+                 */
+                switch ($key) {
+                    case 'port':
+                    case 'accountCanonicalForm':
+                        $permittedOptions[$key] = (int)$val;
+                        break;
+                    case 'useSsl':
+                    case 'bindRequiresDn':
+                    case 'allowEmptyPassword':
+                    case 'useStartTls':
+                    case 'optReferrals':
+                    case 'tryUsernameSplit':
+                        $permittedOptions[$key] = ($val === true ||
+                                $val === '1' || strcasecmp($val, 'true') == 0);
+                        break;
+                    default:
+                        $permittedOptions[$key] = trim($val);
+                        break;
+                }
+            }
+        }
+        if (count($options) > 0) {
+            $key = key($options);
+            /**
+             * @see Zend_Ldap_Exception
+             */
+            require_once 'Zend/Ldap/Exception.php';
+            throw new Zend_Ldap_Exception(null, "Unknown Zend_Ldap option: $key");
+        }
+        $this->_options = $permittedOptions;
+        return $this;
+    }
+
+    /**
+     * @return array The current options.
+     */
+    public function getOptions()
+    {
+        return $this->_options;
+    }
+
+    /**
+     * @return string The hostname of the LDAP server being used to authenticate accounts
+     */
+    protected function _getHost()
+    {
+        return $this->_options['host'];
+    }
+
+    /**
+     * @return int The port of the LDAP server or 0 to indicate that no port value is set
+     */
+    protected function _getPort()
+    {
+        return $this->_options['port'];
+    }
+
+    /**
+     * @return boolean The default SSL / TLS encrypted transport control
+     */
+    protected function _getUseSsl()
+    {
+        return $this->_options['useSsl'];
+    }
+
+    /**
+     * @return string The default acctname for binding
+     */
+    protected function _getUsername()
+    {
+        return $this->_options['username'];
+    }
+
+    /**
+     * @return string The default password for binding
+     */
+    protected function _getPassword()
+    {
+        return $this->_options['password'];
+    }
+
+    /**
+     * @return boolean Bind requires DN
+     */
+    protected function _getBindRequiresDn()
+    {
+        return $this->_options['bindRequiresDn'];
+    }
+
+    /**
+     * Gets the base DN under which objects of interest are located
+     *
+     * @return string
+     */
+    public function getBaseDn()
+    {
+        return $this->_options['baseDn'];
+    }
+
+    /**
+     * @return integer Either ACCTNAME_FORM_BACKSLASH, ACCTNAME_FORM_PRINCIPAL or
+     * ACCTNAME_FORM_USERNAME indicating the form usernames should be canonicalized to.
+     */
+    protected function _getAccountCanonicalForm()
+    {
+        /* Account names should always be qualified with a domain. In some scenarios
+         * using non-qualified account names can lead to security vulnerabilities. If
+         * no account canonical form is specified, we guess based in what domain
+         * names have been supplied.
+         */
+
+        $accountCanonicalForm = $this->_options['accountCanonicalForm'];
+        if (!$accountCanonicalForm) {
+            $accountDomainName = $this->_getAccountDomainName();
+            $accountDomainNameShort = $this->_getAccountDomainNameShort();
+            if ($accountDomainNameShort) {
+                $accountCanonicalForm = Zend_Ldap::ACCTNAME_FORM_BACKSLASH;
+            } else if ($accountDomainName) {
+                $accountCanonicalForm = Zend_Ldap::ACCTNAME_FORM_PRINCIPAL;
+            } else {
+                $accountCanonicalForm = Zend_Ldap::ACCTNAME_FORM_USERNAME;
+            }
+        }
+
+        return $accountCanonicalForm;
+    }
+
+    /**
+     * @return string The account domain name
+     */
+    protected function _getAccountDomainName()
+    {
+        return $this->_options['accountDomainName'];
+    }
+
+    /**
+     * @return string The short account domain name
+     */
+    protected function _getAccountDomainNameShort()
+    {
+        return $this->_options['accountDomainNameShort'];
+    }
+
+    /**
+     * @return string A format string for building an LDAP search filter to match
+     * an account
+     */
+    protected function _getAccountFilterFormat()
+    {
+        return $this->_options['accountFilterFormat'];
+    }
+
+    /**
+     * @return boolean Allow empty passwords
+     */
+    protected function _getAllowEmptyPassword()
+    {
+        return $this->_options['allowEmptyPassword'];
+    }
+
+    /**
+     * @return boolean The default SSL / TLS encrypted transport control
+     */
+    protected function _getUseStartTls()
+    {
+        return $this->_options['useStartTls'];
+    }
+
+    /**
+     * @return boolean Opt. Referrals
+     */
+    protected function _getOptReferrals()
+    {
+        return $this->_options['optReferrals'];
+    }
+
+    /**
+     * @return boolean Try splitting the username into username and domain
+     */
+    protected function _getTryUsernameSplit()
+    {
+        return $this->_options['tryUsernameSplit'];
+    }
+
+    /**
+     * @return string The LDAP search filter for matching directory accounts
+     */
+    protected function _getAccountFilter($acctname)
+    {
+        /**
+         * @see Zend_Ldap_Filter_Abstract
+         */
+        require_once 'Zend/Ldap/Filter/Abstract.php';
+        $this->_splitName($acctname, $dname, $aname);
+        $accountFilterFormat = $this->_getAccountFilterFormat();
+        $aname = Zend_Ldap_Filter_Abstract::escapeValue($aname);
+        if ($accountFilterFormat) {
+            return sprintf($accountFilterFormat, $aname);
+        }
+        if (!$this->_getBindRequiresDn()) {
+            // is there a better way to detect this?
+            return sprintf("(&(objectClass=user)(sAMAccountName=%s))", $aname);
+        }
+        return sprintf("(&(objectClass=posixAccount)(uid=%s))", $aname);
+    }
+
+    /**
+     * @param string $name  The name to split
+     * @param string $dname The resulting domain name (this is an out parameter)
+     * @param string $aname The resulting account name (this is an out parameter)
+     * @return void
+     */
+    protected function _splitName($name, &$dname, &$aname)
+    {
+        $dname = null;
+        $aname = $name;
+
+        if (!$this->_getTryUsernameSplit()) {
+            return;
+        }
+
+        $pos = strpos($name, '@');
+        if ($pos) {
+            $dname = substr($name, $pos + 1);
+            $aname = substr($name, 0, $pos);
+        } else {
+            $pos = strpos($name, '\\');
+            if ($pos) {
+                $dname = substr($name, 0, $pos);
+                $aname = substr($name, $pos + 1);
+            }
+        }
+    }
+
+    /**
+     * @param  string $acctname The name of the account
+     * @return string The DN of the specified account
+     * @throws Zend_Ldap_Exception
+     */
+    protected function _getAccountDn($acctname)
+    {
+        /**
+         * @see Zend_Ldap_Dn
+         */
+        require_once 'Zend/Ldap/Dn.php';
+        if (Zend_Ldap_Dn::checkDn($acctname)) return $acctname;
+        $acctname = $this->getCanonicalAccountName($acctname, Zend_Ldap::ACCTNAME_FORM_USERNAME);
+        $acct = $this->_getAccount($acctname, array('dn'));
+        return $acct['dn'];
+    }
+
+    /**
+     * @param  string $dname The domain name to check
+     * @return boolean
+     */
+    protected function _isPossibleAuthority($dname)
+    {
+        if ($dname === null) {
+            return true;
+        }
+        $accountDomainName = $this->_getAccountDomainName();
+        $accountDomainNameShort = $this->_getAccountDomainNameShort();
+        if ($accountDomainName === null && $accountDomainNameShort === null) {
+            return true;
+        }
+        if (strcasecmp($dname, $accountDomainName) == 0) {
+            return true;
+        }
+        if (strcasecmp($dname, $accountDomainNameShort) == 0) {
+            return true;
+        }
+        return false;
+    }
+
+    /**
+     * @param  string $acctname The name to canonicalize
+     * @param  int    $type     The desired form of canonicalization
+     * @return string The canonicalized name in the desired form
+     * @throws Zend_Ldap_Exception
+     */
+    public function getCanonicalAccountName($acctname, $form = 0)
+    {
+        $this->_splitName($acctname, $dname, $uname);
+
+        if (!$this->_isPossibleAuthority($dname)) {
+            /**
+             * @see Zend_Ldap_Exception
+             */
+            require_once 'Zend/Ldap/Exception.php';
+            throw new Zend_Ldap_Exception(null,
+                "Binding domain is not an authority for user: $acctname",
+                Zend_Ldap_Exception::LDAP_X_DOMAIN_MISMATCH);
+        }
+
+        if (!$uname) {
+            /**
+             * @see Zend_Ldap_Exception
+             */
+            require_once 'Zend/Ldap/Exception.php';
+            throw new Zend_Ldap_Exception(null, "Invalid account name syntax: $acctname");
+        }
+
+        if (function_exists('mb_strtolower')) {
+            $uname = mb_strtolower($uname, 'UTF-8');
+        } else {
+            $uname = strtolower($uname);
+        }
+
+        if ($form === 0) {
+            $form = $this->_getAccountCanonicalForm();
+        }
+
+        switch ($form) {
+            case Zend_Ldap::ACCTNAME_FORM_DN:
+                return $this->_getAccountDn($acctname);
+            case Zend_Ldap::ACCTNAME_FORM_USERNAME:
+                return $uname;
+            case Zend_Ldap::ACCTNAME_FORM_BACKSLASH:
+                $accountDomainNameShort = $this->_getAccountDomainNameShort();
+                if (!$accountDomainNameShort) {
+                    /**
+                     * @see Zend_Ldap_Exception
+                     */
+                    require_once 'Zend/Ldap/Exception.php';
+                    throw new Zend_Ldap_Exception(null, 'Option required: accountDomainNameShort');
+                }
+                return "$accountDomainNameShort\\$uname";
+            case Zend_Ldap::ACCTNAME_FORM_PRINCIPAL:
+                $accountDomainName = $this->_getAccountDomainName();
+                if (!$accountDomainName) {
+                    /**
+                     * @see Zend_Ldap_Exception
+                     */
+                    require_once 'Zend/Ldap/Exception.php';
+                    throw new Zend_Ldap_Exception(null, 'Option required: accountDomainName');
+                }
+                return "$uname@$accountDomainName";
+            default:
+                /**
+                 * @see Zend_Ldap_Exception
+                 */
+                require_once 'Zend/Ldap/Exception.php';
+                throw new Zend_Ldap_Exception(null, "Unknown canonical name form: $form");
+        }
+    }
+
+    /**
+     * @param  array $attrs An array of names of desired attributes
+     * @return array An array of the attributes representing the account
+     * @throws Zend_Ldap_Exception
+     */
+    protected function _getAccount($acctname, array $attrs = null)
+    {
+        $baseDn = $this->getBaseDn();
+        if (!$baseDn) {
+            /**
+             * @see Zend_Ldap_Exception
+             */
+            require_once 'Zend/Ldap/Exception.php';
+            throw new Zend_Ldap_Exception(null, 'Base DN not set');
+        }
+
+        $accountFilter = $this->_getAccountFilter($acctname);
+        if (!$accountFilter) {
+            /**
+             * @see Zend_Ldap_Exception
+             */
+            require_once 'Zend/Ldap/Exception.php';
+            throw new Zend_Ldap_Exception(null, 'Invalid account filter');
+        }
+
+        if (!is_resource($this->getResource())) {
+            $this->bind();
+        }
+
+        $accounts = $this->search($accountFilter, $baseDn, self::SEARCH_SCOPE_SUB, $attrs);
+        $count = $accounts->count();
+        if ($count === 1) {
+            $acct = $accounts->getFirst();
+            $accounts->close();
+            return $acct;
+        } else if ($count === 0) {
+            /**
+             * @see Zend_Ldap_Exception
+             */
+            require_once 'Zend/Ldap/Exception.php';
+            $code = Zend_Ldap_Exception::LDAP_NO_SUCH_OBJECT;
+            $str = "No object found for: $accountFilter";
+        } else {
+            /**
+             * @see Zend_Ldap_Exception
+             */
+            require_once 'Zend/Ldap/Exception.php';
+            $code = Zend_Ldap_Exception::LDAP_OPERATIONS_ERROR;
+            $str = "Unexpected result count ($count) for: $accountFilter";
+        }
+        $accounts->close();
+        /**
+         * @see Zend_Ldap_Exception
+         */
+        require_once 'Zend/Ldap/Exception.php';
+        throw new Zend_Ldap_Exception($this, $str, $code);
+    }
+
+    /**
+     * @return Zend_Ldap Provides a fluent interface
+     */
+    public function disconnect()
+    {
+        if (is_resource($this->_resource)) {
+            @ldap_unbind($this->_resource);
+        }
+        $this->_resource = null;
+        $this->_boundUser = false;
+        return $this;
+    }
+
+    /**
+     * To connect using SSL it seems the client tries to verify the server
+     * certificate by default. One way to disable this behavior is to set
+     * 'TLS_REQCERT never' in OpenLDAP's ldap.conf and restarting Apache. Or,
+     * if you really care about the server's cert you can put a cert on the
+     * web server.
+     *
+     * @param  string  $host        The hostname of the LDAP server to connect to
+     * @param  int     $port        The port number of the LDAP server to connect to
+     * @param  boolean $useSsl      Use SSL
+     * @param  boolean $useStartTls Use STARTTLS
+     * @return Zend_Ldap Provides a fluent interface
+     * @throws Zend_Ldap_Exception
+     */
+    public function connect($host = null, $port = null, $useSsl = null, $useStartTls = null)
+    {
+        if ($host === null) {
+            $host = $this->_getHost();
+        }
+        if ($port === null) {
+            $port = $this->_getPort();
+        } else {
+            $port = (int)$port;
+        }
+        if ($useSsl === null) {
+            $useSsl = $this->_getUseSsl();
+        } else {
+            $useSsl = (bool)$useSsl;
+        }
+        if ($useStartTls === null) {
+            $useStartTls = $this->_getUseStartTls();
+        } else {
+            $useStartTls = (bool)$useStartTls;
+        }
+
+        if (!$host) {
+            /**
+             * @see Zend_Ldap_Exception
+             */
+            require_once 'Zend/Ldap/Exception.php';
+            throw new Zend_Ldap_Exception(null, 'A host parameter is required');
+        }
+
+        $useUri = false;
+        /* Because ldap_connect doesn't really try to connect, any connect error
+         * will actually occur during the ldap_bind call. Therefore, we save the
+         * connect string here for reporting it in error handling in bind().
+         */
+        $hosts = array();
+        if (preg_match_all('~ldap(?:i|s)?://~', $host, $hosts, PREG_SET_ORDER) > 0) {
+            $this->_connectString = $host;
+            $useUri = true;
+            $useSsl = false;
+        } else {
+            if ($useSsl) {
+                $this->_connectString = 'ldaps://' . $host;
+                $useUri = true;
+            } else {
+                $this->_connectString = 'ldap://' . $host;
+            }
+            if ($port) {
+                $this->_connectString .= ':' . $port;
+            }
+        }
+
+        $this->disconnect();
+
+        /* Only OpenLDAP 2.2 + supports URLs so if SSL is not requested, just
+         * use the old form.
+         */
+        $resource = ($useUri) ? @ldap_connect($this->_connectString) : @ldap_connect($host, $port);
+
+        if (is_resource($resource) === true) {
+            $this->_resource = $resource;
+            $this->_boundUser = false;
+
+            $optReferrals = ($this->_getOptReferrals()) ? 1 : 0;
+            if (@ldap_set_option($resource, LDAP_OPT_PROTOCOL_VERSION, 3) &&
+                        @ldap_set_option($resource, LDAP_OPT_REFERRALS, $optReferrals)) {
+                if ($useSsl || !$useStartTls || @ldap_start_tls($resource)) {
+                    return $this;
+                }
+            }
+
+            /**
+             * @see Zend_Ldap_Exception
+             */
+            require_once 'Zend/Ldap/Exception.php';
+            $zle = new Zend_Ldap_Exception($this, "$host:$port");
+            $this->disconnect();
+            throw $zle;
+        }
+        /**
+         * @see Zend_Ldap_Exception
+         */
+        require_once 'Zend/Ldap/Exception.php';
+        throw new Zend_Ldap_Exception(null, "Failed to connect to LDAP server: $host:$port");
+    }
+
+    /**
+     * @param  string $username The username for authenticating the bind
+     * @param  string $password The password for authenticating the bind
+     * @return Zend_Ldap Provides a fluent interface
+     * @throws Zend_Ldap_Exception
+     */
+    public function bind($username = null, $password = null)
+    {
+        $moreCreds = true;
+
+        if ($username === null) {
+            $username = $this->_getUsername();
+            $password = $this->_getPassword();
+            $moreCreds = false;
+        }
+
+        if (empty($username)) {
+            /* Perform anonymous bind
+             */
+            $username = null;
+            $password = null;
+        } else {
+            /* Check to make sure the username is in DN form.
+             */
+            /**
+             * @see Zend_Ldap_Dn
+             */
+            require_once 'Zend/Ldap/Dn.php';
+            if (!Zend_Ldap_Dn::checkDn($username)) {
+                if ($this->_getBindRequiresDn()) {
+                    /* moreCreds stops an infinite loop if _getUsername does not
+                     * return a DN and the bind requires it
+                     */
+                    if ($moreCreds) {
+                        try {
+                            $username = $this->_getAccountDn($username);
+                        } catch (Zend_Ldap_Exception $zle) {
+                            switch ($zle->getCode()) {
+                                case Zend_Ldap_Exception::LDAP_NO_SUCH_OBJECT:
+                                case Zend_Ldap_Exception::LDAP_X_DOMAIN_MISMATCH:
+                                case Zend_Ldap_Exception::LDAP_X_EXTENSION_NOT_LOADED:
+                                    throw $zle;
+                            }
+                            throw new Zend_Ldap_Exception(null,
+                                'Failed to retrieve DN for account: ' . $username .
+                                ' [' . $zle->getMessage() . ']',
+                                Zend_Ldap_Exception::LDAP_OPERATIONS_ERROR);
+                        }
+                    } else {
+                        /**
+                         * @see Zend_Ldap_Exception
+                         */
+                        require_once 'Zend/Ldap/Exception.php';
+                        throw new Zend_Ldap_Exception(null, 'Binding requires username in DN form');
+                    }
+                } else {
+                    $username = $this->getCanonicalAccountName($username,
+                        $this->_getAccountCanonicalForm());
+                }
+            }
+        }
+
+        if (!is_resource($this->_resource)) {
+            $this->connect();
+        }
+
+        if ($username !== null && $password === '' && $this->_getAllowEmptyPassword() !== true) {
+            /**
+             * @see Zend_Ldap_Exception
+             */
+            require_once 'Zend/Ldap/Exception.php';
+            $zle = new Zend_Ldap_Exception(null,
+                'Empty password not allowed - see allowEmptyPassword option.');
+        } else {
+            if (@ldap_bind($this->_resource, $username, $password)) {
+                $this->_boundUser = $username;
+                return $this;
+            }
+
+            $message = ($username === null) ? $this->_connectString : $username;
+            /**
+             * @see Zend_Ldap_Exception
+             */
+            require_once 'Zend/Ldap/Exception.php';
+            switch ($this->getLastErrorCode()) {
+                case Zend_Ldap_Exception::LDAP_SERVER_DOWN:
+                    /* If the error is related to establishing a connection rather than binding,
+                     * the connect string is more informative than the username.
+                     */
+                    $message = $this->_connectString;
+            }
+
+            $zle = new Zend_Ldap_Exception($this, $message);
+        }
+        $this->disconnect();
+        throw $zle;
+    }
+
+    /**
+     * A global LDAP search routine for finding information.
+     *
+     * Options can be either passed as single parameters according to the
+     * method signature or as an array with one or more of the following keys
+     * - filter
+     * - baseDn
+     * - scope
+     * - attributes
+     * - sort
+     * - collectionClass
+     * - sizelimit
+     * - timelimit
+     *
+     * @param  string|Zend_Ldap_Filter_Abstract|array $filter
+     * @param  string|Zend_Ldap_Dn|null               $basedn
+     * @param  integer                                $scope
+     * @param  array                                  $attributes
+     * @param  string|null                            $sort
+     * @param  string|null                            $collectionClass
+     * @param  integer                            	  $sizelimit
+     * @param  integer                            	  $timelimit
+     * @return Zend_Ldap_Collection
+     * @throws Zend_Ldap_Exception
+     */
+    public function search($filter, $basedn = null, $scope = self::SEARCH_SCOPE_SUB, array $attributes = array(),
+        $sort = null, $collectionClass = null, $sizelimit = 0, $timelimit = 0)
+    {
+        if (is_array($filter)) {
+            $options = array_change_key_case($filter, CASE_LOWER);
+            foreach ($options as $key => $value) {
+                switch ($key) {
+                    case 'filter':
+                    case 'basedn':
+                    case 'scope':
+                    case 'sort':
+                        $$key = $value;
+                        break;
+                    case 'attributes':
+                        if (is_array($value)) {
+                            $attributes = $value;
+                        }
+                        break;
+                    case 'collectionclass':
+                        $collectionClass = $value;
+                        break;
+                    case 'sizelimit':
+                    case 'timelimit':
+                        $$key = (int)$value;
+                }
+            }
+        }
+
+        if ($basedn === null) {
+            $basedn = $this->getBaseDn();
+        }
+        else if ($basedn instanceof Zend_Ldap_Dn) {
+            $basedn = $basedn->toString();
+        }
+
+        if ($filter instanceof Zend_Ldap_Filter_Abstract) {
+            $filter = $filter->toString();
+        }
+
+        switch ($scope) {
+            case self::SEARCH_SCOPE_ONE:
+                $search = @ldap_list($this->getResource(), $basedn, $filter, $attributes, 0, $sizelimit, $timelimit);
+                break;
+            case self::SEARCH_SCOPE_BASE:
+                $search = @ldap_read($this->getResource(), $basedn, $filter, $attributes, 0, $sizelimit, $timelimit);
+                break;
+            case self::SEARCH_SCOPE_SUB:
+            default:
+                $search = @ldap_search($this->getResource(), $basedn, $filter, $attributes, 0, $sizelimit, $timelimit);
+                break;
+        }
+
+        if($search === false) {
+            /**
+             * @see Zend_Ldap_Exception
+             */
+            require_once 'Zend/Ldap/Exception.php';
+            throw new Zend_Ldap_Exception($this, 'searching: ' . $filter);
+        }
+        if ($sort !== null && is_string($sort)) {
+            $isSorted = @ldap_sort($this->getResource(), $search, $sort);
+            if($isSorted === false) {
+                /**
+                 * @see Zend_Ldap_Exception
+                 */
+                require_once 'Zend/Ldap/Exception.php';
+                throw new Zend_Ldap_Exception($this, 'sorting: ' . $sort);
+            }
+        }
+
+        /**
+         * Zend_Ldap_Collection_Iterator_Default
+         */
+        require_once 'Zend/Ldap/Collection/Iterator/Default.php';
+        $iterator = new Zend_Ldap_Collection_Iterator_Default($this, $search);
+        return $this->_createCollection($iterator, $collectionClass);
+    }
+
+    /**
+     * Extension point for collection creation
+     *
+     * @param  Zend_Ldap_Collection_Iterator_Default	$iterator
+     * @param  string|null								$collectionClass
+     * @return Zend_Ldap_Collection
+     * @throws Zend_Ldap_Exception
+     */
+    protected function _createCollection(Zend_Ldap_Collection_Iterator_Default $iterator, $collectionClass)
+    {
+        if ($collectionClass === null) {
+            /**
+             * Zend_Ldap_Collection
+             */
+            require_once 'Zend/Ldap/Collection.php';
+            return new Zend_Ldap_Collection($iterator);
+        } else {
+            $collectionClass = (string)$collectionClass;
+            if (!class_exists($collectionClass)) {
+                /**
+                 * @see Zend_Ldap_Exception
+                 */
+                require_once 'Zend/Ldap/Exception.php';
+                throw new Zend_Ldap_Exception(null,
+                    "Class '$collectionClass' can not be found");
+            }
+            if (!is_subclass_of($collectionClass, 'Zend_Ldap_Collection')) {
+                /**
+                 * @see Zend_Ldap_Exception
+                 */
+                require_once 'Zend/Ldap/Exception.php';
+                throw new Zend_Ldap_Exception(null,
+                    "Class '$collectionClass' must subclass 'Zend_Ldap_Collection'");
+            }
+            return new $collectionClass($iterator);
+        }
+    }
+
+    /**
+     * Count items found by given filter.
+     *
+     * @param  string|Zend_Ldap_Filter_Abstract $filter
+     * @param  string|Zend_Ldap_Dn|null         $basedn
+     * @param  integer                          $scope
+     * @return integer
+     * @throws Zend_Ldap_Exception
+     */
+    public function count($filter, $basedn = null, $scope = self::SEARCH_SCOPE_SUB)
+    {
+        try {
+            $result = $this->search($filter, $basedn, $scope, array('dn'), null);
+        } catch (Zend_Ldap_Exception $e) {
+            if ($e->getCode() === Zend_Ldap_Exception::LDAP_NO_SUCH_OBJECT) return 0;
+            else throw $e;
+        }
+        return $result->count();
+    }
+
+    /**
+     * Count children for a given DN.
+     *
+     * @param  string|Zend_Ldap_Dn $dn
+     * @return integer
+     * @throws Zend_Ldap_Exception
+     */
+    public function countChildren($dn)
+    {
+        return $this->count('(objectClass=*)', $dn, self::SEARCH_SCOPE_ONE);
+    }
+
+    /**
+     * Check if a given DN exists.
+     *
+     * @param  string|Zend_Ldap_Dn $dn
+     * @return boolean
+     * @throws Zend_Ldap_Exception
+     */
+    public function exists($dn)
+    {
+        return ($this->count('(objectClass=*)', $dn, self::SEARCH_SCOPE_BASE) == 1);
+    }
+
+    /**
+     * Search LDAP registry for entries matching filter and optional attributes
+     *
+     * Options can be either passed as single parameters according to the
+     * method signature or as an array with one or more of the following keys
+     * - filter
+     * - baseDn
+     * - scope
+     * - attributes
+     * - sort
+     * - reverseSort
+     * - sizelimit
+     * - timelimit
+     *
+     * @param  string|Zend_Ldap_Filter_Abstract|array $filter
+     * @param  string|Zend_Ldap_Dn|null               $basedn
+     * @param  integer                                $scope
+     * @param  array                                  $attributes
+     * @param  string|null                            $sort
+     * @param  boolean                                $reverseSort
+     * @param  integer                            	  $sizelimit
+     * @param  integer                            	  $timelimit
+     * @return array
+     * @throws Zend_Ldap_Exception
+     */
+    public function searchEntries($filter, $basedn = null, $scope = self::SEARCH_SCOPE_SUB,
+        array $attributes = array(), $sort = null, $reverseSort = false, $sizelimit = 0, $timelimit = 0)
+    {
+        if (is_array($filter)) {
+            $filter = array_change_key_case($filter, CASE_LOWER);
+            if (isset($filter['collectionclass'])) {
+                unset($filter['collectionclass']);
+            }
+            if (isset($filter['reversesort'])) {
+                $reverseSort = $filter['reversesort'];
+                unset($filter['reversesort']);
+            }
+        }
+        $result = $this->search($filter, $basedn, $scope, $attributes, $sort, null, $sizelimit, $timelimit);
+        $items = $result->toArray();
+        if ((bool)$reverseSort === true) {
+            $items = array_reverse($items, false);
+        }
+        return $items;
+    }
+
+    /**
+     * Get LDAP entry by DN
+     *
+     * @param  string|Zend_Ldap_Dn $dn
+     * @param  array               $attributes
+     * @param  boolean             $throwOnNotFound
+     * @return array
+     * @throws Zend_Ldap_Exception
+     */
+    public function getEntry($dn, array $attributes = array(), $throwOnNotFound = false)
+    {
+        try {
+            $result = $this->search("(objectClass=*)", $dn, self::SEARCH_SCOPE_BASE,
+                $attributes, null);
+            return $result->getFirst();
+        } catch (Zend_Ldap_Exception $e){
+            if ($throwOnNotFound !== false) throw $e;
+        }
+        return null;
+    }
+
+    /**
+     * Prepares an ldap data entry array for insert/update operation
+     *
+     * @param  array $entry
+     * @return void
+     * @throws InvalidArgumentException
+     */
+    public static function prepareLdapEntryArray(array &$entry)
+    {
+        if (array_key_exists('dn', $entry)) unset($entry['dn']);
+        foreach ($entry as $key => $value) {
+            if (is_array($value)) {
+                foreach ($value as $i => $v) {
+                    if ($v === null) unset($value[$i]);
+                    else if (!is_scalar($v)) {
+                        throw new InvalidArgumentException('Only scalar values allowed in LDAP data');
+                    } else {
+                        $v = (string)$v;
+                        if (strlen($v) == 0) {
+                            unset($value[$i]);
+                        } else {
+                            $value[$i] = $v;
+                        }
+                    }
+                }
+                $entry[$key] = array_values($value);
+            } else {
+                if ($value === null) $entry[$key] = array();
+                else if (!is_scalar($value)) {
+                    throw new InvalidArgumentException('Only scalar values allowed in LDAP data');
+                } else {
+                    $value = (string)$value;
+                    if (strlen($value) == 0) {
+                        $entry[$key] = array();
+                    } else {
+                        $entry[$key] = array($value);
+                    }
+                }
+            }
+        }
+        $entry = array_change_key_case($entry, CASE_LOWER);
+    }
+
+    /**
+     * Add new information to the LDAP repository
+     *
+     * @param  string|Zend_Ldap_Dn $dn
+     * @param  array               $entry
+     * @return Zend_Ldap                  Provides a fluid interface
+     * @throws Zend_Ldap_Exception
+     */
+    public function add($dn, array $entry)
+    {
+        if (!($dn instanceof Zend_Ldap_Dn)) {
+            $dn = Zend_Ldap_Dn::factory($dn, null);
+        }
+        self::prepareLdapEntryArray($entry);
+        foreach ($entry as $key => $value) {
+            if (is_array($value) && count($value) === 0) {
+                unset($entry[$key]);
+            }
+        }
+
+        $rdnParts = $dn->getRdn(Zend_Ldap_Dn::ATTR_CASEFOLD_LOWER);
+        foreach ($rdnParts as $key => $value) {
+            $value = Zend_Ldap_Dn::unescapeValue($value);
+            if (!array_key_exists($key, $entry)) {
+                $entry[$key] = array($value);
+            } else if (!in_array($value, $entry[$key])) {
+                $entry[$key] = array_merge(array($value), $entry[$key]);
+            }
+        }
+        $adAttributes = array('distinguishedname', 'instancetype', 'name', 'objectcategory',
+            'objectguid', 'usnchanged', 'usncreated', 'whenchanged', 'whencreated');
+        foreach ($adAttributes as $attr) {
+            if (array_key_exists($attr, $entry)) {
+                unset($entry[$attr]);
+            }
+        }
+
+        $isAdded = @ldap_add($this->getResource(), $dn->toString(), $entry);
+        if($isAdded === false) {
+            /**
+             * @see Zend_Ldap_Exception
+             */
+            require_once 'Zend/Ldap/Exception.php';
+            throw new Zend_Ldap_Exception($this, 'adding: ' . $dn->toString());
+        }
+        return $this;
+    }
+
+    /**
+     * Update LDAP registry
+     *
+     * @param  string|Zend_Ldap_Dn $dn
+     * @param  array               $entry
+     * @return Zend_Ldap                  Provides a fluid interface
+     * @throws Zend_Ldap_Exception
+     */
+    public function update($dn, array $entry)
+    {
+        if (!($dn instanceof Zend_Ldap_Dn)) {
+            $dn = Zend_Ldap_Dn::factory($dn, null);
+        }
+        self::prepareLdapEntryArray($entry);
+
+        $rdnParts = $dn->getRdn(Zend_Ldap_Dn::ATTR_CASEFOLD_LOWER);
+        foreach ($rdnParts as $key => $value) {
+            $value = Zend_Ldap_Dn::unescapeValue($value);
+            if (array_key_exists($key, $entry) && !in_array($value, $entry[$key])) {
+                $entry[$key] = array_merge(array($value), $entry[$key]);
+            }
+        }
+
+        $adAttributes = array('distinguishedname', 'instancetype', 'name', 'objectcategory',
+            'objectguid', 'usnchanged', 'usncreated', 'whenchanged', 'whencreated');
+        foreach ($adAttributes as $attr) {
+            if (array_key_exists($attr, $entry)) {
+                unset($entry[$attr]);
+            }
+        }
+
+        if (count($entry) > 0) {
+            $isModified = @ldap_modify($this->getResource(), $dn->toString(), $entry);
+            if($isModified === false) {
+                /**
+                 * @see Zend_Ldap_Exception
+                 */
+                require_once 'Zend/Ldap/Exception.php';
+                throw new Zend_Ldap_Exception($this, 'updating: ' . $dn->toString());
+            }
+        }
+        return $this;
+    }
+
+    /**
+     * Save entry to LDAP registry.
+     *
+     * Internally decides if entry will be updated to added by calling
+     * {@link exists()}.
+     *
+     * @param  string|Zend_Ldap_Dn $dn
+     * @param  array               $entry
+     * @return Zend_Ldap Provides a fluid interface
+     * @throws Zend_Ldap_Exception
+     */
+    public function save($dn, array $entry)
+    {
+        if ($dn instanceof Zend_Ldap_Dn) {
+            $dn = $dn->toString();
+        }
+        if ($this->exists($dn)) $this->update($dn, $entry);
+        else $this->add($dn, $entry);
+        return $this;
+    }
+
+    /**
+     * Delete an LDAP entry
+     *
+     * @param  string|Zend_Ldap_Dn $dn
+     * @param  boolean             $recursively
+     * @return Zend_Ldap Provides a fluid interface
+     * @throws Zend_Ldap_Exception
+     */
+    public function delete($dn, $recursively = false)
+    {
+        if ($dn instanceof Zend_Ldap_Dn) {
+            $dn = $dn->toString();
+        }
+        if ($recursively === true) {
+            if ($this->countChildren($dn)>0) {
+                $children = $this->_getChildrenDns($dn);
+                foreach ($children as $c) {
+                    $this->delete($c, true);
+                }
+            }
+        }
+        $isDeleted = @ldap_delete($this->getResource(), $dn);
+        if($isDeleted === false) {
+            /**
+             * @see Zend_Ldap_Exception
+             */
+            require_once 'Zend/Ldap/Exception.php';
+            throw new Zend_Ldap_Exception($this, 'deleting: ' . $dn);
+        }
+        return $this;
+    }
+
+    /**
+     * Retrieve the immediate children DNs of the given $parentDn
+     *
+     * This method is used in recursive methods like {@see delete()}
+     * or {@see copy()}
+     *
+     * @param  string|Zend_Ldap_Dn $parentDn
+     * @return array of DNs
+     */
+    protected function _getChildrenDns($parentDn)
+    {
+        if ($parentDn instanceof Zend_Ldap_Dn) {
+            $parentDn = $parentDn->toString();
+        }
+        $children = array();
+        $search = @ldap_list($this->getResource(), $parentDn, '(objectClass=*)', array('dn'));
+        for ($entry = @ldap_first_entry($this->getResource(), $search);
+                $entry !== false;
+                $entry = @ldap_next_entry($this->getResource(), $entry)) {
+            $childDn = @ldap_get_dn($this->getResource(), $entry);
+            if ($childDn === false) {
+                /**
+                 * @see Zend_Ldap_Exception
+                 */
+                require_once 'Zend/Ldap/Exception.php';
+                throw new Zend_Ldap_Exception($this, 'getting dn');
+            }
+            $children[] = $childDn;
+        }
+        @ldap_free_result($search);
+        return $children;
+    }
+
+    /**
+     * Moves a LDAP entry from one DN to another subtree.
+     *
+     * @param  string|Zend_Ldap_Dn $from
+     * @param  string|Zend_Ldap_Dn $to
+     * @param  boolean             $recursively
+     * @param  boolean             $alwaysEmulate
+     * @return Zend_Ldap Provides a fluid interface
+     * @throws Zend_Ldap_Exception
+     */
+    public function moveToSubtree($from, $to, $recursively = false, $alwaysEmulate = false)
+    {
+        if ($from instanceof Zend_Ldap_Dn) {
+            $orgDnParts = $from->toArray();
+        } else {
+            $orgDnParts = Zend_Ldap_Dn::explodeDn($from);
+        }
+
+        if ($to instanceof Zend_Ldap_Dn) {
+            $newParentDnParts = $to->toArray();
+        } else {
+            $newParentDnParts = Zend_Ldap_Dn::explodeDn($to);
+        }
+
+        $newDnParts = array_merge(array(array_shift($orgDnParts)), $newParentDnParts);
+        $newDn = Zend_Ldap_Dn::fromArray($newDnParts);
+        return $this->rename($from, $newDn, $recursively, $alwaysEmulate);
+    }
+
+    /**
+     * Moves a LDAP entry from one DN to another DN.
+     *
+     * This is an alias for {@link rename()}
+     *
+     * @param  string|Zend_Ldap_Dn $from
+     * @param  string|Zend_Ldap_Dn $to
+     * @param  boolean             $recursively
+     * @param  boolean             $alwaysEmulate
+     * @return Zend_Ldap Provides a fluid interface
+     * @throws Zend_Ldap_Exception
+     */
+    public function move($from, $to, $recursively = false, $alwaysEmulate = false)
+    {
+        return $this->rename($from, $to, $recursively, $alwaysEmulate);
+    }
+
+    /**
+     * Renames a LDAP entry from one DN to another DN.
+     *
+     * This method implicitely moves the entry to another location within the tree.
+     *
+     * @param  string|Zend_Ldap_Dn $from
+     * @param  string|Zend_Ldap_Dn $to
+     * @param  boolean             $recursively
+     * @param  boolean             $alwaysEmulate
+     * @return Zend_Ldap Provides a fluid interface
+     * @throws Zend_Ldap_Exception
+     */
+    public function rename($from, $to, $recursively = false, $alwaysEmulate = false)
+    {
+        $emulate = (bool)$alwaysEmulate;
+        if (!function_exists('ldap_rename')) $emulate = true;
+        else if ($recursively) $emulate = true;
+
+        if ($emulate === false) {
+            if ($from instanceof Zend_Ldap_Dn) {
+                $from = $from->toString();
+            }
+
+            if ($to instanceof Zend_Ldap_Dn) {
+                $newDnParts = $to->toArray();
+            } else {
+                $newDnParts = Zend_Ldap_Dn::explodeDn($to);
+            }
+
+            $newRdn = Zend_Ldap_Dn::implodeRdn(array_shift($newDnParts));
+            $newParent = Zend_Ldap_Dn::implodeDn($newDnParts);
+            $isOK = @ldap_rename($this->getResource(), $from, $newRdn, $newParent, true);
+            if($isOK === false) {
+                /**
+                 * @see Zend_Ldap_Exception
+                 */
+                require_once 'Zend/Ldap/Exception.php';
+                throw new Zend_Ldap_Exception($this, 'renaming ' . $from . ' to ' . $to);
+            }
+            else if (!$this->exists($to)) $emulate = true;
+        }
+        if ($emulate) {
+            $this->copy($from, $to, $recursively);
+            $this->delete($from, $recursively);
+        }
+        return $this;
+    }
+
+    /**
+     * Copies a LDAP entry from one DN to another subtree.
+     *
+     * @param  string|Zend_Ldap_Dn $from
+     * @param  string|Zend_Ldap_Dn $to
+     * @param  boolean             $recursively
+     * @return Zend_Ldap Provides a fluid interface
+     * @throws Zend_Ldap_Exception
+     */
+    public function copyToSubtree($from, $to, $recursively = false)
+    {
+        if ($from instanceof Zend_Ldap_Dn) {
+            $orgDnParts = $from->toArray();
+        } else {
+            $orgDnParts = Zend_Ldap_Dn::explodeDn($from);
+        }
+
+        if ($to instanceof Zend_Ldap_Dn) {
+            $newParentDnParts = $to->toArray();
+        } else {
+            $newParentDnParts = Zend_Ldap_Dn::explodeDn($to);
+        }
+
+        $newDnParts = array_merge(array(array_shift($orgDnParts)), $newParentDnParts);
+        $newDn = Zend_Ldap_Dn::fromArray($newDnParts);
+        return $this->copy($from, $newDn, $recursively);
+    }
+
+    /**
+     * Copies a LDAP entry from one DN to another DN.
+     *
+     * @param  string|Zend_Ldap_Dn $from
+     * @param  string|Zend_Ldap_Dn $to
+     * @param  boolean             $recursively
+     * @return Zend_Ldap Provides a fluid interface
+     * @throws Zend_Ldap_Exception
+     */
+    public function copy($from, $to, $recursively = false)
+    {
+        $entry = $this->getEntry($from, array(), true);
+
+        if ($to instanceof Zend_Ldap_Dn) {
+            $toDnParts = $to->toArray();
+        } else {
+            $toDnParts = Zend_Ldap_Dn::explodeDn($to);
+        }
+        $this->add($to, $entry);
+
+        if ($recursively === true && $this->countChildren($from)>0) {
+            $children = $this->_getChildrenDns($from);
+            foreach ($children as $c) {
+                $cDnParts = Zend_Ldap_Dn::explodeDn($c);
+                $newChildParts = array_merge(array(array_shift($cDnParts)), $toDnParts);
+                $newChild = Zend_Ldap_Dn::implodeDn($newChildParts);
+                $this->copy($c, $newChild, true);
+            }
+        }
+        return $this;
+    }
+
+    /**
+     * Returns the specified DN as a Zend_Ldap_Node
+     *
+     * @param  string|Zend_Ldap_Dn $dn
+     * @return Zend_Ldap_Node|null
+     * @throws Zend_Ldap_Exception
+     */
+    public function getNode($dn)
+    {
+        /**
+         * Zend_Ldap_Node
+         */
+        require_once 'Zend/Ldap/Node.php';
+        return Zend_Ldap_Node::fromLdap($dn, $this);
+    }
+
+    /**
+     * Returns the base node as a Zend_Ldap_Node
+     *
+     * @return Zend_Ldap_Node
+     * @throws Zend_Ldap_Exception
+     */
+    public function getBaseNode()
+    {
+        return $this->getNode($this->getBaseDn(), $this);
+    }
+
+    /**
+     * Returns the RootDSE
+     *
+     * @return Zend_Ldap_Node_RootDse
+     * @throws Zend_Ldap_Exception
+     */
+    public function getRootDse()
+    {
+        if ($this->_rootDse === null) {
+            /**
+             * @see Zend_Ldap_Node_Schema
+             */
+            require_once 'Zend/Ldap/Node/RootDse.php';
+            $this->_rootDse = Zend_Ldap_Node_RootDse::create($this);
+        }
+        return $this->_rootDse;
+    }
+
+    /**
+     * Returns the schema
+     *
+     * @return Zend_Ldap_Node_Schema
+     * @throws Zend_Ldap_Exception
+     */
+    public function getSchema()
+    {
+        if ($this->_schema === null) {
+            /**
+             * @see Zend_Ldap_Node_Schema
+             */
+            require_once 'Zend/Ldap/Node/Schema.php';
+            $this->_schema = Zend_Ldap_Node_Schema::create($this);
+        }
+        return $this->_schema;
+    }
+}