ldap_explode_dn

(PHP 4, PHP 5, PHP 7)

ldap_explode_dn — Splits DN into its component parts

Description

array ldap_explode_dn ( string $dn , int $with_attrib )

Splits the DN returned by ldap_get_dn() and breaks it up into its component parts. Each part is known as Relative Distinguished Name, or RDN.

Parameters

dn: The distinguished name of an LDAP entity.
with_attrib: Used to request if the RDNs are returned with only values or their attributes as well. To get RDNs with the attributes (i.e. in attribute=value format) set with_attrib to 0 and to get only values set it to 1.

Return Values

Returns an array of all DN components. The first element in this array has count key and represents the number of returned values, next elements are numerically indexed DN components.

User Contributed Notes

hello+php at NOSPAM dot renoirboulanger dot com

3 years ago


I came accros this page and enjoyed the comments. 



Since a LDAP string can sometimes be lengthy and have many attributes, I needed to be able to sort through all that is in.



In my case, I needed to get the subdomain part and other parameters. 



Here is how I built my method.

<?php

    /**

     * Parse, and format a DN string to Array

     *

     * Read a LDAP DN, and return an array keys

     * listing all similar attributes.

     *

     * Also takes care of the character escape and unescape

     *

     * Example:

     * CN=username,OU=UNITNAME,OU=Region,OU=Country,DC=subdomain,DC=domain,DC=com

     *

     * Would normally return:

     * Array (

     *     [count] => 9

     *     [0] => CN=username

     *     [1] => OU=UNITNAME

     *     [2] => OU=Region

     *     [5] => OU=Country

     *     [6] => DC=subdomain

     *     [7] => DC=domain

     *     [8] => DC=com

     * )

     *

     * Returns instead a manageable array:

     * array (

     *     [CN] => array( username )

     *     [OU] => array( UNITNAME, Region, Country )

     *     [DC] => array ( subdomain, domain, com )

     * )

     *

     *

     * @author gabriel at hrz dot uni-marburg dot de 05-Aug-2003 02:27 (part of the character replacement)

     * @author Renoir Boulanger

     * 

     * @param  string $dn          The DN

     * @return array

     */

    function parseLdapDn($dn)

    {

        $parsr=ldap_explode_dn($dn, 0);

        //$parsr[] = 'EE=Sôme Krazï string';

        //$parsr[] = 'AndBogusOne';

        $out = array();

        foreach($parsr as $key=>$value){

            if(FALSE !== strstr($value, '=')){

                list($prefix,$data) = explode("=",$value);

                $data=preg_replace("/\\\\\\([0-9A-Fa-f]{2})/e", "''.chr(hexdec('\\\\1')).''", $data);

                if(isset($current_prefix) && $prefix == $current_prefix){

                    $out[$prefix][] = $data;

                } else {

                    $current_prefix = $prefix;

                    $out[$prefix][] = $data;

                }

            }

        }

        return $out;

    }

?>

gabriel at hrz dot uni-marburg dot de

12 years ago


Keep attention on UTF8 encoded DNs. Since openLDAP >=2.1.2
ldap_explode_dn turns unprintable chars (in the ASCII sense, UTF8
encoded) into \<hexcode>.

Example:

$dn="ou=Universität ,c=DE";
var_dump(ldap_explode_dn($dn,0));

//returns

array(3) {
  ["count"]=>
  int(2)
  [0]=>
  string(19) "ou=Universit\C3\A4t"
  [1]=>
  string(4) "c=DE"
}

Unfortunately, PHP don't support the ldap functions ldap_str2dn and 
ldap_dn2str, but by means of preg_replace a workaround is possible to
recover the old behaviour of ldap_explode_dn

// workaround
function myldap_explode_dn($dn,$with_attribute){

$result=ldap_explode_dn ($dn, $with_attrib);
 //translate hex code into ascii again
    foreach($result as $key=>$value){
          $result[$key]=preg_replace("/\\\([0-9A-Fa-f]{2})/e", "''.chr(hexdec('\\1')).''", $value);
    }
    return($result);

}
//
//then follows for the example

$dn="ou=Universität ,c=DE";
var_dump(myldap_explode_dn($dn,0));

//returns

array(3) {
  ["count"]=>
  int(2)
  [0]=>
  string(15) "ou=Universität"
  [1]=>
  string(4) "c=DE"
}

DavidSmith at byu dot net

12 years ago


[ Editor's Note: The segfault has been fixed and will not occur in PHP 4.3.4 or PHP 5.0.0 when they are released.  However, it is still important to escape special characters as detailed below. ]



If your DN contains < or > characters, you must escape them with a backslash or ldap_explode_dn() will give you a "wrong parameter count" error or even a segmentation fault.



For example, these calls will fail with a "wrong parameter count" or a seg fault:



  ldap_explode_dn( "cn=<bob>,dc=example,dc=com", 0 );

  ldap_explode_dn( 'cn=<bob>,dc=example,dc=com', 0 );



But this will succeed



  ldap_explode_dn( "cn=\<bob\>,dc=example,dc=com", 0 );



Notice also that the < and > are escaped with hex codes as noted above. This function is a nice wrapper that properly formats all DNs and can safely be called with < and > characters, and UTF-8 characters:



function my_explode_dn( $dn, $with_attributes=0 )

{

        $dn = addcslashes( $dn, "<>" );

        $result = ldap_explode_dn( $dn, $with_attributes );

        //translate hex code into ascii again

        foreach( $result as $key => $value )

                $result[$key] = preg_replace("/\\\([0-9A-Fa-f]{2})/e", "''.chr(hexdec('\\1')).''", $value);

        return $result;

}



I am using php 4.3.1. Good luck!

bs at muekno dot de

14 years ago


Copying is much better than typing!!!!

Just modify the constants.

Best wishes (and thanX 4 this helpfull site),

Bernd Schwaegerl

Mueller-Knoche GmbH, Systemhaus fuer EDV-Loesungen



# Example:



$HOST = "Yourhostname";

$USER_DN = "Yourldapuser_dn";

$PWD = "Ldapuserpassword";

$BASE_DN = "o=Your_organisation";

$SEARCH_OBJECT="sn=YOUR_SEARCH_PERSON_OBJECTS_SN";



$ldap_handle=ldap_connect($HOST);

$bind_result=ldap_bind($ldap_handle,$USER_DN,$PWD);



$search_result=ldap_search($ldap_handle,$BASE_DN,$SEARCH_OBJECT);

$result=ldap_get_entries($ldap_handle,$search_result);

$result_array=ldap_get_entries($ldap_handle,$result);

$whole_dn=$result_array[0]["dn"];



$dn_parts=ldap_explode_dn($whole_dn,0);