Re: How would I do this? (expert tricks) OT

[Bill Davidsen]

Marc Perkel wrote:
> I have a server with port 25 closed. I was to be able
> to run a script every time someone tries to connect to
> port 25, but from the outside the port remains closed.
> I need the script that I'm going to run get the IP
> address that tried to connect.
>
> I know it's off topic but it's part of an experiment
> to stop spam. 

Put a rule in iptables to jump to a user table to do a log and drop. You 
are doing it the wrong way, you want to set syslog to write the log 
message to a FIFO and have a permanent running program reading it (I do 
just this for other things).

Alternatively you can use redirect to send it to a program of your 
choosing, which can run a script if you really want to. Beware that rate 
limiting is desirable if you are going to start a process for ANY type 
of attack packets.

--
Bill Davidsen <davidsen@xxxxxxx>
  "We have more to fear from the bungling of the incompetent than from
the machinations of the wicked."  - from Slashdot
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