Here is my chilli.iptables file that is located in /etc/init.d/
/etc/init.d# cat chilli.iptables
# Firewall script for ChilliSpot
# A Wireless LAN Access Point Controller
# Uses $EXTIF (eth0) as the external interface (Internet or intranet) and
# $INTIF (eth1) as the internal interface (access points).
# * All connections originating from chilli are allowed.
# * Only ssh is allowed in on external interface.
# * Nothing is allowed in on internal interface.
# * Forwarding is allowed to and from the external interface, but disallowed
# to and from the internal interface.
# * NAT is enabled on the external interface.
$IPTABLES -P INPUT DROP
$IPTABLES -P FORWARD ACCEPT
$IPTABLES -P OUTPUT ACCEPT
#Allow related and established on all interfaces (input)
$IPTABLES -A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT
#Allow releated, established and ssh on $EXTIF. Reject everything else.
$IPTABLES -A INPUT -i $EXTIF -p tcp -m tcp --dport 22 --syn -j ACCEPT
$IPTABLES -A INPUT -i $EXTIF -j REJECT
#Allow related and established from $INTIF. Drop everything else.
$IPTABLES -A INPUT -i $INTIF -j DROP
#Allow http and https on other interfaces (input).
#This is only needed if authentication server is on same server as chilli
$IPTABLES -A INPUT -p tcp -m tcp --dport 80 --syn -j ACCEPT
$IPTABLES -A INPUT -p tcp -m tcp --dport 443 --syn -j ACCEPT
#Allow 3990 on other interfaces (input).
$IPTABLES -A INPUT -p tcp -m tcp --dport 3990 --syn -j ACCEPT
#Allow everything on loopback interface.
$IPTABLES -A INPUT -i lo -j ACCEPT
# Drop everything to and from $INTIF (forward)
# This means that access points can only be managed from ChilliSpot
$IPTABLES -A FORWARD -i $INTIF -j DROP
$IPTABLES -A FORWARD -o $INTIF -j DROP
#Enable NAT on output device
$IPTABLES -t nat -A POSTROUTING -o $EXTIF -j MASQUERADE