On Mon, Jul 11, 2005 at 07:58:15PM +0500, azeem ahmad wrote: > hi list > here is a script that i want to use to block unauthorized MACs on my > network. but the problem is that its not blocking all other MACs that r > not specified in the script. plz help me out n telll wots the reaon of this > ######################################################## > iptables -A INPUT -m mac --mac-source $MAC -j ACCEPT > iptables -A FORWARD -m mac --mac-source $MAC -j ACCEPT > iptables -A INPUT -m mac --mac-source ! 11:22:33:44:55:66 -j DROP > iptables -A FORWARD -m mac --mac-source ! 11:22:33:44:55:66 -j DROP > iptables -t nat -A POSTROUTING -i eth1 -j MASQUERADE > ################################################### > even now it is MASQUERADING all the macs that r not specified in the script. > waiting for ur response > Regards i would do it this way: iptables -N check_mac iptables -A check_mac -m mac --mac-source $MAC1 -j RETURN iptables -A check_mac -m mac --mac-source $MAC2 -j RETURN # iptables -A check_mac -j LOG --log-prefix "INVALID MAC: " iptables -A check_mac -j DROP iptables -A INPUT -j check_mac iptables -A FORWARD -j check_mac and then put your regular filter rules in INPUT and FORWARD after the jump to check_mac; as only packets with either $MAC1 or $MAC2 will ever make it out of the check_mac chain. -j -- "Lois: I'm sorry that Stewie ruined your books. Here, I brought you some of Peter's. Brian: "Mr. T" by Mr. T. "T and Me" by George Poppard. "For The Last Time, I'm Not Mr. T" by Ving Rhames." --Family Guy