diff --git a/src/includes/functions.php b/src/includes/functions.php
index 58c2fb97..09574e54 100644
--- a/src/includes/functions.php
+++ b/src/includes/functions.php
@@ -405,6 +405,35 @@ function sumDn($dn1,$dn2) {
   return $basedn;
 }
 
+/**
+ * Extract and retreive RDN from DN
+ * @param string $dn
+ * @param bool $with_attr If true, include the RDN attribute name (optional, default: true)
+ * @return string|null|false The parent object DN, null if no parent or false in case of error
+ */
+function getRdn($dn, $with_attr=true) {
+  $parts = ldap_explode_dn($dn, 0);
+  if (!is_array($parts) || !isset($parts['count'])) return false;
+  if ($with_attr)
+    return $parts[0];
+  $equal_pos = strpos($parts[0], '=');
+  if ($equal_pos !== false)
+    return substr($parts[0], $equal_pos+1);
+  return $parts[0];
+}
+
+/**
+ * Retreive parent object DN
+ * @param string $dn
+ * @return string|null|false The parent object DN, null if no parent or false in case of error
+ */
+function parentDn($dn) {
+  $parts = ldap_explode_dn($dn, 0);
+  if (!is_array($parts) || !isset($parts['count'])) return false;
+  if ($parts['count'] == 1) return null;
+  return implode(',', array_slice($parts, 2));
+}
+
 function checkEmail($value,$domain=NULL,$checkDns=true) {
   $log = LSlog :: get_logger('checkEmail');
   $regex = '/^((\"[^\"\f\n\r\t\v\b]+\")|([\w\!\#\$\%\&\'\*\+\-\~\/\^\`\|\{\}]+(\.[\w\!\#\$\%\&\'\*\+\-\~\/\^\`\|\{\}]+)*))@((\[(((25[0-5])|(2[0-4][0-9])|([0-1]?[0-9]?[0-9]))\.((25[0-5])|(2[0-4][0-9])|([0-1]?[0-9]?[0-9]))\.((25[0-5])|(2[0-4][0-9])|([0-1]?[0-9]?[0-9]))\.((25[0-5])|(2[0-4][0-9])|([0-1]?[0-9]?[0-9])))\])|(((25[0-5])|(2[0-4][0-9])|([0-1]?[0-9]?[0-9]))\.((25[0-5])|(2[0-4][0-9])|([0-1]?[0-9]?[0-9]))\.((25[0-5])|(2[0-4][0-9])|([0-1]?[0-9]?[0-9]))\.((25[0-5])|(2[0-4][0-9])|([0-1]?[0-9]?[0-9])))|((([A-Za-z0-9\-])+\.)+[A-Za-z\-]+))$/';