LRO code should deal with all 12 TCP header flags

[rscheff]

Summary

RFC793 has 4 reserved flag bits for future use. One of those
bits used to be assigned to ECN Nonce (now historic), and
may be reused for AccurateECN.

This patch is to include these bits in the LRO code to ease
the extensibility if/when these bits are used.

[• hselasky]

sys/netinet/tcp_lro.h

151

Maybe you should add a "reserved : 2", so that the bitfields fill the 16- bits available.

[• hselasky]

Looks good.

[rscheff]

• add comments and reserve remainder of bitfield

[• hselasky]

sys/netinet/tcp_lro.c

924

Maybe a macro to do exactly this would be at its place?

#define TCP_GET_FLAGS(th) (((th)->th_x2 << 8) | ((th)->th_flags))

--HPS

[rscheff]

sys/netinet/tcp_lro.c

924

A good idea. But I would do that as a separate Diff, as there are (already) a couple places scattered across the base stack, where this would come in handy...

[rrs]

This looks good but I want to pull it down and see if it will compile ;)