http://firewalladdons.sourceforge.net/
qui trovi tutti gli addons, esiste anche Advanced Proxy, è quello che cerchi !
leggi qui:
dvanced Proxy is an add-on module for IPCop, extending the web proxy functionality with a lot of versatile and useful additional features.
- Key features of Advanced Proxy
- Seamless GUI integration for advanced web proxy configuration
-
Local user authentication including group based user management
- LDAP authentication including Active Directory, eDirectory and OpenLDAP
- Windows authentication including Windows NT/2003 domains and Samba
- Extended cache management
- Network based access control over IP and MAC addresses
- Time based access restrictions
- MIME type filter
- Blocking of unauthorized browsers or client software.
E qui trovi tutta la documentazione a riguardo
http://www.advproxy.net/
fammi sapere assolutamente !!!