You default policy is ACCEPT :INPUT ACCEPT [0:0] :FORWARD ACCEPT [0:0] :OUTPUT ACCEPT [0:0] Change to DROP :INPUT DROP [0:0] :FORWARD DROP [0:0] :OUTPUT ACCEPT [0:0] It's ok to leave the output ACCEPT (so I've heard) -----Original Message----- From: Ryan Golhar [mailto:golharam@xxxxxxxxx] Sent: Thursday, April 08, 2004 9:21 AM To: redhat-list@xxxxxxxxxx Subject: What am I doing wrong with Iptables? I'm trying to secure a server using iptables. My iptables looks like this: # Firewall configuration written by redhat-config-securitylevel # Manual customization of this file is not recommended. *filter :INPUT ACCEPT [0:0] :FORWARD ACCEPT [0:0] :OUTPUT ACCEPT [0:0] :RH-Firewall-1-INPUT - [0:0] -A INPUT -j RH-Firewall-1-INPUT -A FORWARD -j RH-Firewall-1-INPUT -A RH-Firewall-1-INPUT -i lo -j ACCEPT #-A RH-Firewall-1-INPUT -p icmp --icmp-type any -j ACCEPT #-A RH-Firewall-1-INPUT -p 50 -j ACCEPT #-A RH-Firewall-1-INPUT -p 51 -j ACCEPT -A RH-Firewall-1-INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT -A RH-Firewall-1-INPUT -m state --state NEW -m tcp -p tcp --dport 22 -j ACCEPT -A RH-Firewall-1-INPUT -j REJECT --reject-with icmp-host-prohibited COMMIT If I understand it correctly, it should only allow traffic on tcp port 22. However, if I start the dhcp server, and request a dhcp address from another machine, it succeeds. I would expect iptables to block this traffic. I'm apparently doing something wrong, but I'm not sure what it is ----- Ryan Golhar Computational Biologist The Informatics Institute at The University of Medicine & Dentistry of NJ Phone: 973-972-5034 Fax: 973-972-7412 Email: golharam@xxxxxxxxx -- redhat-list mailing list unsubscribe mailto:redhat-list-request@xxxxxxxxxx?subject=unsubscribe https://www.redhat.com/mailman/listinfo/redhat-list -- redhat-list mailing list unsubscribe mailto:redhat-list-request@xxxxxxxxxx?subject=unsubscribe https://www.redhat.com/mailman/listinfo/redhat-list
