IPSec transport mode, mtu, fragmentation...

[Victor Sudakov]

Eugene Grosbein wrote:
> 
> > What beats me is that I cannot reproduce this problem in bhyve. In this
> > packet dump: http://admin.sibptus.ru/~vas/ipsec1.pcap.gz I'm scp-ing a
> > 50M file from 192.168.246.10 (bhyve guest) to 192.168.246.1 (bhyve
> > host), and I see no fragments, and the largets packet is 1466 bytes, and
> > the scp never stalls nor fails.
> > 
> > Why is it NOT broken this time?
> > 
> > Both hosts are 12.1-RELEASE-p1.
> 
> I could not reproduce the problem with unpatched recent stable/11, either :-)

Is there a way to view the MSS in the TCP segments before encryption or
after decryption? I want to compare them in situations with IPSec
enabled and disabled.

I've never been able to see anything in "tcpdump -i enc0", probably it
cannot do transport mode IPSec because the man page talks about "outer
and inner header."

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