Re: replacing tcp fields

From: Karl Williams (
Date: Sat Apr 28 2001 - 13:04:50 EST

Sounds like a plan. Unfortunately, I can't seem to get into the site. Would you know if this is mirrored somewhere else? I especially need to see the documentation (obviously).
>> Thanks for the idea. However, looking over the netfilter information,
>> it seems that I can only specify certain TCP fields to mangle.
>> I don't see where I can manipulate the checksum and/or data fields.
>> Am I missing something?
>No, once you have a packet in userspace you have access to all the fields
>in tcp.h.. including checksum.
>> >You can obviously use Netfilter ( with queueing
>> >rules in the OUTPUT chain.
>> >
>> >On Thu, 26 Apr 2001, Karl Williams wrote:
>> >
>> >> >> I need to replace the data field and the checksum field in a tcp packet with other information (not related to the socket or socket buffer).
>> >>
>> >> >Where is the packet originating from? Does it originate from a program on
>> >> >your computer, or some other machine addressed to your computer, or just
>> >> >forwarded through your computer?
>> >>
>> >> The packet itself is generated on my own machine. I assume it's using the TCP subroutines in the .../net/ipv4 directory.

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This archive was generated by hypermail 2b29 : Mon Apr 30 2001 - 21:00:29 EST