On Sun, 2003-05-04 at 14:38, John Guntenaar wrote: I missed the start of this thread, so I backed up and reread it. :^) > Hello, > > I have a linux machine with 4 IP addresses, I have a couple of friends > on that machine and I don't allow them to use IRC, so I simply blocked > the IRC ports, but I want to use IRC from the 4th IP without the other > users being able to use it. I think I can reach that goal by using the > owner match facility of iptables, though I can't find any good examples > with google, is it correct and can somebody post an example? > > Thanks in advantage, > > John You need something constructed like this: iptables -A OUTPUT -p tcp --dport 194 -m owner ! --uid-owner \ 1235 -j REJECT --reject-with tcp-reset or: iptables -A OUTPUT -p tcp --dport 194 -m owner --uid-owner \ 1235 -j ACCEPT I use a similar rule to prevent any user except root from being able to connect to my LAN computers from my server. You can add an additional match to either rule to match outgoing interface or sourceIP if needed. Is it really necessary to restrict IRC to only that single IP? j
