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Hello all,
I have a protocol/dissector called vrf.
vrf = ip/tcp/vrf/vrf payload
vrf payload = ip/tcp...
To manage vrf payload, I do :
call_dissector(<ip dissector handle>, next_tvb, pinfo,
tree);
Globaly, it is working.
BUT, not with the following scheme (4 packet contains 3 vrf
message/pdu) :
|-- packet1 --||-- packet2 --||--- packet3
---||----- packet4 -----|
|------- vrf 1 --------||----- vrf 2 -------------||-----
vrf 3 ---|
In this case, my dissector is NOT called for packet 3.
--> NOT ok
At the end of call_dissector into vrf 1, some fields of pinfo have
been modified, at least :
- net_src
- net_dst
- src
- dst
- srcport not matching the
ones used for dissector_add_uint
- destport not matching the
ones used for dissector_add_uint
Start reading vrf 2 and stop (because packet2 has no enough data)
with :
pinfo->desegment_offset = 0; /* Start at
beginning next time */
pinfo->desegment_len = DESEGMENT_ONE_MORE_SEGMENT;
Then, my dissector is NOT called for packet3 (it is called for
packet4).
--> NOT ok
I suppose that the pinfo modifications are the reasons for which
my dissector is not called for packet3 ?
When I cancel these modifications before continue, it works.
NB: it works if I use
call_dissector(<data dissector handle>,
next_tvb, pinfo, tree);
What is wrong ?
What is the normal way to manage this ?
Thanks,
Olivier
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