getAllows()

    array getAllows(string objectClassName)
This function will return an array of the attributes which the specified objectClass allows based on what you have defined in your slapd.oc.conf file.

Example: 

$ldap = new LDAP();
$oc = "organizationalUnit";
$allowed = $ldap->getAllows($oc);
echo "ObjectClass '$oc' allows the following attributes:<br>";
for ($ctr = 0; $ctr < count($allowed); $ctr++)
{
	echo $allowed[$ctr] . "<br>\n";
}