OT: FERM Help With NAT

[Luke Davis]

Hello

I am trying to configure firm to do various firewall and routing tasks.

I need this FERM script to handle source NAT.

I have a system with two interfaces: eth0 is public, with a static IP; and
eth1 supports a private class C.
External IP: 123.123.123.456
Class C: 192.168.10.0/24

Currently, I am doing this with IPTables as follows:

iptables -t nat -A POSTROUTING -o eth0 -s 192.168.10/24 -j SNAT \
--to-source 123.123.123.456

I think, that I do not understand enough about how iptables is handling
this, to manage to put it into FERM-speak.

Has anyone done this, or does anyone know enough about FERM to know how to
do source NAT for the situation I describe?

Thanks

Luke