Jan Engelhardt jengelh at linux01.gwdg.de
Thu Jul 28 08:34:18 CEST 2005

>> > you are right..i'm having a scripting problem..i don't know how to
>> > make a script execute every time a packet is sent by my PC. how can i
>> > do that?
>> You don't want to execute a script for each packet... you could be
>> easily DoSed. Try:
>> http://netfilter.org/patch-o-matic/pom-base.html#pom-base-nth
>> Please reply to the list, so everyone can help and learn. =)
>No I only want to execute a script for all packets that are packets
>that are going to be sent out of the NIC (after the packets have been

That's still a DOS. If I pingflood you, your machine will most likely respond 
with "pongflood".

I have iptraf running for like 4 or 5 days now and it shows almost 11 GB 
which approximates to ~ 34 KB/sec (inet radio ;). Let's assume that every 
packet was 1500 bytes long - then this would mean that I would be starting 23 
processes per second, which really is inefficient.

And, you're looking for -j QUEUE.

>accepted as valid by a firewall). I don't know how to do that. Do you
>know what is the last function in the iptables code or the first
>function in the NIC driver, that a packet that has been accepted by
>the firewall passes before it is sent on the wire? I would then write
>some code so that when a call is made to that function, a signal is
>raised and it will cause a shell script to execute.
>I don't know abt the DoSed command. Do you have any example?
>If there is an easier way, please let me know...
>MAny thx for the reply.
>Warm regards,

Jan Engelhardt
| Alphagate Systems, http://alphagate.hopto.org/

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