Re: Resend TCP segment modified to the sender

["Kotatsu" <naughtydog@virgilio.it>]

>
> It's possible and you can modify any packet you capture. What do u mean by
> "which field"? You just need to write a couple of rules to put packets
into
> QUEUE.

I've maded a C program that take packet from the queue with libipq.h
I've a scipt that queue all the packet sended by my host:

iptables -A FORWARD -j QUEUE

My program catch this packet, see if in this TCP data packet there is a
particular sequence number (for example 10) in the data filed, and if it is
i want that netfilter resend this packet modified to the client. I want to
modify the TCP data packet from data packet to ACK with window advertise =0.
The purpouse of this is to freeze TCP on client (with window probe
thecnique). So i want to know how I must modify my packet to do this.

I've already modified a server data packet to ACK with window size=0, but
now i must reuse a client packet as a server packet.
Best regards
Marco A.