My INPUT chain has the ACCEPT policy, on my linux gateway. This system has
2 interfaces. One is a modem interface (Internet) and the other is a ethernet interface (Intranet).
For the modem interface, I setup the following rules,
$ ipchains -A input -i ppp0 -p 21 -j DENY
$ ipchains -A input -i ppp0 -p 23 -j DENY
$ ipchains -A input -i ppp0 -p 80 -j DENY
My goal in this exercise is to prevent outside telnet, ftp and www access
to my gateway.
From a remote machine(from a different LAN on the Intranet), I can still access these service.
What is wrong with the above rules? What am I doing wrong?
Thanks you in advance for your input.
subb3 at ibm.net
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