[plug] ipchains -> iptables

[Mark Nold]

I got started on iptables (with no idea of ipchains) from the "Masquerading 
Made Simple HOWTO"

I have a hard copy of it, but unfortunatly www.linuxdoc.org seems down (i 
think thats where i got it from)

For dialup ppp it recommended the following. NB: I added the "rmmod ipchains" 
any idea of how to get rid of the ipchains module... it doesnt appear to be 
in /etc/modules.conf (Redhat 7.2)

I'm using this whilst digesting the "Security Quick-Start HOWTO for Redhat 
Linux" ... which isnt as quick as says ;)



#!/bin/sh
# IP Tables to secure a dialup connection
ifup ppp0
rmmod ipchains
# Fisrt MASQUERADING
modprobe ipt_MASQUERADE
iptables -F; iptables -t nat -F; iptables -t mangle -F
iptables -t nat -A POSTROUTING -o ppp0 -j MASQUERADE
echo 1 > /proc/sys/net/ipv4/ip_forward

# Now Secure the interface
iptables -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT
iptables -A INPUT -m state --state NEW -i ! ppp0 -j ACCEPT
iptables -P INPUT DROP
iptables -A FORWARD -i ppp0 -o ppp0 -j REJECT