svn commit: r343525 - in head/sys/netinet: . tcp_stacks

[Ryan Stone]

On Mon, Jan 28, 2019 at 7:46 AM Michael Tuexen <tuexen at freebsd.org> wrote:
>
> Author: tuexen
> Date: Mon Jan 28 12:45:31 2019
> New Revision: 343525
> URL: https://svnweb.freebsd.org/changeset/base/343525
>
> Log:
>   Fix the detection of ECN-setup SYN-ACK packets.
>
>   RFC 3168 defines an ECN-setup SYN-ACK packet as on with the ECE flags
>   set and the CWR flags not set. The code was only checking if ECE flag
>   is set. This patch adds the check to verify that the CWR flags is not
>   set.

Is this compatible with DCTCP?  I seem to recall that it is possible
for pure ACKs to be ECN marked in DCTCP.