IPSec transport mode, mtu, fragmentation...

[Victor Sudakov]

Victor Sudakov wrote:
> Michael Sierchio wrote:
> > 
> > What is the result of
> > 
> > > sysctl net.enc
> 
> ot at fbsd-test1:~ # sysctl net.enc
> net.enc.out.ipsec_bpf_mask: 3
> net.enc.out.ipsec_filter_mask: 0
> net.enc.in.ipsec_bpf_mask: 1
> net.enc.in.ipsec_filter_mask: 0
> 
> > 
> > ?  This might be a clue about the packets, which you could be seeing twice.
> > 
> 
> An artifact of enc0, you think ? Are the above settings sending the
> packets to if_enc twice?

I just made a small experiment: sent 20 pings from 192.168.246.10 to
192.168.246.11, and I see that each echo reply is duplicated, so there
are 60 packets totally in the traffic dump: 20 requests and 40 replies:
http://admin.sibptus.ru/~vas/i1.pcap

So this is most probably the artifact of if_enc. What is then the
correct way to capture data with it?


-- 
Victor Sudakov,  VAS4-RIPE, VAS47-RIPN
2:5005/49 at fidonet http://vas.tomsk.ru/
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