Unusual TCP options can cause FreeBSD to issue a reset

[Kevin Oberman]

I have a system that is unable to connect to a FreeBSD system due to
the odd formatting of the TCP options. The options contains only the
timestamp which, if recommendations in RFC1323 are followed, are
preceded by two NOP bytes to put the timestamp values on 4 byte
boundaries.

This system sends the 12 byte timestamp option alone, followed by two
zero bytes to pad it. This meets the requirements of RFC793 and 1323 is
explicit that stacks must accept this, even though it results in
sub-optimal performance and does not meet the recommendations in 1323
appendix A.

Any idea if this is hard to fix? I see in on both 7.2 and 8.0.
-- 
R. Kevin Oberman, Network Engineer
Energy Sciences Network (ESnet)
Ernest O. Lawrence Berkeley National Laboratory (Berkeley Lab)
E-mail: oberman at es.net			Phone: +1 510 486-8634
Key fingerprint:059B 2DDF 031C 9BA3 14A4  EADA 927D EBB3 987B 3751