tcp checksum calculation

[Amit Shah <anirane@ip.eth.net>]

Hi,
   I have a function(in the kernel, ip_rcv_finish... before the ip
forwarding code.) that takes in packets, replaces the dest. ip:port, and
sends to that machine. (ip forwarding is enabled.) I need to recalculate
the checksum..... ip checksumming works fine(ip_fast_csum)... but, the tcp
checksum is shown as incorrect on ethereal. The packets are not delivered
to the new dest.... 

Also, what is the skb->csum, in case there is no data (e.g.  for ACK or
FIN -only packets)?

TIA,

--- 

  - Amit
http://amitshah.nav.to/
amitshah@gmx.net
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