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Wireshark-dev: Re: [Wireshark-dev] reasebling packets - dissector question

From: יוני תובל <yoni6666@xxxxxxxxx>
Date: Mon, 23 Feb 2009 12:57:32 +0200
hi , thanks .
it seems to be working , but only when i raise the flag "pinfo->can_desegment=1  "  inside the get_len method .
but i noticed that the TCP checksum test fails in all the reassembled packets .
why is that ?
actually it also fails when i send the whole message in one buffer ...
so its probably a different issue . . .
 

thanks
2009/2/23 Guy Harris <guy@xxxxxxxxxxxx>

On Feb 23, 2009, at 12:59 AM, יוני תובל wrote:

> i tried to return the entire message length . still fails .
> (it only succeeds when the tvb consists of the entire message )
> What about he offest value we pass to the get_len method .

It's the offset into the tvbuff handed to the get_len routine of the
first byte of the packet whose length should be returned.

Presumably the PDUs consist of a 2-byte length field (in network byte
order?) followed by that number of bytes of data, and, in the get_len
routine, you fetch the length value from the packet, add 2 to it, and
return that value.
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