Re: ipnat filtering exception

In some mail from Billy Newsom, sie said:
>
> I am using the ipfilter built into FreeBSD 5.4 v3.4.35 (336). I just
> came across a need to use a new redirect, but I don't see anything in
> the Howto discussing it, which usually fixes me up.
>
> I have this new rule:
> rdr fxp0 0.0.0.0/0 port 25 -> 192.168.0.1 port 2525
>
> This will allow all port 25 traffic starting from LAN to WAN to go to
> port 2525 on a machine of my choice.
>
> Exception 1.
> Fine, but I need to make a few exceptions. For example, say I have a PC
> at 192.168.5.5 that needs to be excepted. How do I keep this PC from
> being redirected?

rdr fxp0 from ! 192.168.5.5/32 to 0.0.0.0/0 port 25 -> 192.168.0.1 port 2525 tcp

Although this doesn't work well if there's a number of individual addresses
that you want to make this exception for,

> Exception 2.
> Also, what if we contact a special server, which needs no redirection?
> Say, server 192.168.0.1 port 25 traffic is legitimate, and everyone on
> the LAN should receive *no* redirection for that special server?

Easiest way to achieve this is to redirect it to that adddress.
e.g.:

rdr fxp0 192.168.0.1/32 port 25 -> 0/0 port 25 tcp

Darren