I am reinstalling my router box and will upgrade from kernel 2.2 to 2.4
My existing ruleset for masquerading uses IPCHAINS. If I provide it here, could some great soul intruct me on making the proper edits to make it work with IPTABLES?
Also, if I'm using IPTABLES, what net modules should I be installing to allow the masquerading, and eventually in the future to allow firewalling and maybe port forwarding as I may want to do some type of hosting on my internal LAN.

Thanks,
James

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-- the external NIC retrieves IP through DHCP from ISP
-- the internal NIC is assigned static IP info through use of: /etc/network/interfaces
-- the box is running Debian stable BTW

#!/bin/sh
INTLAN="192.168.0.0/24"
INTIF="eth0"
EXTIF="eth1"
echo "1" > /proc/sys/net/ipv4/ip_dynaddr
/sbin/ipchains -A input -j ACCEPT -i $EXTIF -s 0/0 67 -d 0/0 68 -p udp
EXTIP="`/sbin/ifconfig eth1 | grep 'inet addr' | awk '{print $2}' | sed -e 's/.*://'`"
/sbin/depmod -a
/sbin/modprobe ip_masq_ftp
/sbin/modprobe ip_masq_raudio
echo "1" > /proc/sys/net/ipv4/ip_forward
echo "1" > /proc/sys/net/ipv4/ip_always_defrag
/sbin/ipchains -M -S 7200 10 160
/sbin/ipchains -P input ACCEPT
/sbin/ipchains -P output ACCEPT
/sbin/ipchains -P forward REJECT
/sbin/ipchains -F input
/sbin/ipchains -F output
/sbin/ipchains -F forward
/sbin/ipchains -P forward DENY
/sbin/ipchains -A forward -i $EXTIF -s $INTLAN -j MASQ

Almost the same except

/sbin/iptables -A INPUT (INPUT, OUTPUT, FORWARD etc should be in CAPS)

and

/sbin/iptables -A FORWARD -i $EXTIF -s $INTLAN -j MASQUERADE

have a look at rusty's nat-howto-2.4 www.netfilter.org www.iptables.org for further infos. it has really gotten a more powerful tool.