radius x509 authentication + LDAP ?

Hello, I am actually using freeradius with EAP-TLS and x509 user certificat authentication. After authentication I would like to chack the common name or email address propertires of te certificate againsta LDAP, to authorize the user connection. is it possible to do this ? I tyed but it seems not working in my configuration. any hints ? thank you very much Riccardo