Yeah man, Smoothwall is for Linux. There are also firewalling/gateway tools built right into Linux. You can use IPTables if you are using a newer verison of Linux, like RedHat 7.2, or you can use IPChains (what I use) if you have an older verison of RedHat, like verison 7.1. IPChains is easier to use and setup than IPTables but IPTables is a little more robust. And there is a tool that comes with RedHat 7.1 called firewall-config, it is a GUI front end to IPChains so you can setup Masquerading and Port and Address Blocking. Remember that if you only need one command to turn on forwarding: ipchains -A forward -j MASQ -i eth0 -s 0.0.0.0/0 -d 0.0.0.0/0 (where eth0 or eth1 is the NIC connected to your LAN). That is your basic forwarding chain that doesn't care what it forwards and from whom, if you are worried about someone using your network and getting to the outside world you could make it a little harder by making it only for a couple of addresses on your LAN, or a pool of them with a subnet mask, but that is just paranoia. There is a tutorial on
www.linux.com you can also use free software called Freesco and LRP (Linux Router Project) which is just a floppy verison of Linux that doesn't need an HD, boots right from your floppy and is easy to setup.