From mboxrd@z Thu Jan  1 00:00:00 1970
From: Pablo Neira <pablo@eurodev.net>
Subject: Re: How to avoid fragmentation
Date: Thu, 27 Oct 2005 14:41:07 +0200
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To: Gervasio Bernal <gervasiobernal@speedy.com.ar>
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Hi,

Gervasio Bernal wrote:
> I will show you an example:
> 
> +---------------+	
> |    IP		|	
> |    header 	|	
> |---------------|
> |    TCP	|
> |    header 	|
> |---------------|
> |  My header	|
> |---------------|
> |		|
> |   USER DATA	|
> |		|
> +---------------+
> 
> I calculte the USER DATA checksum and put it in a field of My header.
> If the packet is larger than MTU, it will be fragmented and the checksum
> calculated in My header will be incorrect when I recieve it in the other
> endpoint of the communication.
> 
> There is some form to avoid the fragmentation?

In this case, have a look at skb_checksum()

-- 
Pablo