I've been searching around and couldn't find a full description of the
pfsync header format and all the different types of messages (some
kind of RFC).
Do you guys know whether or not there exists such a document ? or
something similar that would review in details al the types of
messages for pfsync ?
I've read David Gwynne's paper about pfsync_v5
(openbsd.org/papers/pfsync_v5.pdf), and he gives a quick list of the
different message types, but its work is 2 years old and maybe the
protocol evolved since then ? Are there no other message types in the
current implementation ?
Also, does the protocol implement some kind of reliability mechanism,
like message sequencing / acknowledgements messages ? How would pfsync
behave in an environment with limited bandwith and subject to packets
Lastly, I'd like to test pfsync in a simulated environment with
potential packets loss/corruptions and/or with limited bandwith.
I know I can emulate packets loss by adding probability to a block
rule in pf.conf, and I'm not sure but I think ALTQ could help to add
some bandwith limitation (though its main goal is more to implement
QoS rules, again correct me if I'm wrong).
I've heard of Dummynet for FreeBSD ; is there the equivalent for OpenBSD ?
Thanks for reading me,
University of Sherbrooke,