Hi,

Hope someone can help me with a question of payload reassembly.

First up, I have been trawling the e-mail archives to find an equivalent answer 
and was wondering if there is a better way of searching the e-mail archives 
than opening up each individual month/year?

Now my actual question is that I am dissecting  a packet payload which is split 
up into fragments with specific chunks as:
Begin
Middle (no begin/end flagged, so can be multiple)
End

I have a simple state machine that checks these transitions and keeps fragment 
counts so I can then call fragment_add_seq_check() with an appropriate unique 
id and an incrementing (from zero) frag_number.  I know the size of the 
individual fragments and there is a sequence number that increments on each 
packet, though a packet can have multiple fragments for the same or different 
channels .

This appears to 'initially' work ok from the various log prints I had added to 
check returns from process_reassembled_data() and the actual reassembled TVB 
size.

The problem I have, and this is probably my fundamental misunderstanding, is 
that it works on the initial pass through the packets but breaks horribly when 
I click on an individual packet as we are mid fragments. I also notice that 
wireshark parses the whole file once and then parses again the visible packets 
in the summary window, this also fails as the 1st packet is parsed again after 
the last which could be in any state of fragmentation.

I suppose I am thinking if we have parsed the payload once for a given 
packet/fragment we should not parse and reassemble again but somehow look-up 
what reassembled payload it belongs to? Using something like fragment_get() ?

Anyway I don't think I am doing anything unusual at all so perhaps someone can 
enlighten me on my missing fundamental?

Thanks,

John

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