From: Jesper Dangaard Brouer <brouer@redhat.com>
To: Eric Dumazet <eric.dumazet@gmail.com>
Cc: "David Miller" <davem@davemloft.net>,
netdev <netdev@vger.kernel.org>,
"Francesco Fusco" <fusco@ntop.org>,
"Maciej Żenczykowski" <maze@google.com>,
brouer@redhat.com
Subject: Re: [PATCH net-next] ipv4: accept u8 in IP_TOS ancillary data
Date: Tue, 13 Sep 2016 09:07:32 +0200 [thread overview]
Message-ID: <20160913090732.069417a2@redhat.com> (raw)
In-Reply-To: <1473341474.15733.36.camel@edumazet-glaptop3.roam.corp.google.com>
On Thu, 08 Sep 2016 06:31:14 -0700
Eric Dumazet <eric.dumazet@gmail.com> wrote:
> On Thu, 2016-09-08 at 11:15 +0200, Jesper Dangaard Brouer wrote:
> > On Wed, 07 Sep 2016 21:52:56 -0700
> > Eric Dumazet <eric.dumazet@gmail.com> wrote:
> >
> > > From: Eric Dumazet <edumazet@google.com>
> > >
> > > In commit f02db315b8d8 ("ipv4: IP_TOS and IP_TTL can be specified as
> > > ancillary data") Francesco added IP_TOS values specified as integer.
> > >
> > > However, kernel sends to userspace (at recvmsg() time) an IP_TOS value
> > > in a single byte, when IP_RECVTOS is set on the socket.
> > >
> > > It can be very useful to reflect all ancillary options as given by the
> > > kernel in a subsequent sendmsg(), instead of aborting the sendmsg() with
> > > EINVAL after Francesco patch.
> > >
> > > So this patch extends IP_TOS ancillary to accept an u8, so that an UDP
> > > server can simply reuse same ancillary block without having to mangle
> > > it.
> > >
> > > Jesper can then augment
> > > https://github.com/netoptimizer/network-testing/blob/master/src/udp_example02.c
> > > to add TOS reflection ;)
> >
> > This is actually your old program ;-)
> > Do I need to change anything, as I'm just bouncing the packet back with sendmsg() ?
>
> I guess you want to add an option and if this option is requested by the
> user, add :
>
> setsockopt(fd, SOL_IP, IP_PKTINFO, &on, sizeof(on));
> + if (tos_reflect)
> + setsockopt(fd, SOL_IP, IP_RECVTOS, &on, sizeof(on));
>
> before the loop doing the recvmsg()/sendmsg() calls.
Hi Eric,
I've implemented what you suggested:
https://github.com/netoptimizer/network-testing/commit/0758ad77a96ecb1
Now QA can use this tool to verify the kernel commit ;-)
--
Best regards,
Jesper Dangaard Brouer
MSc.CS, Principal Kernel Engineer at Red Hat
Author of http://www.iptv-analyzer.org
LinkedIn: http://www.linkedin.com/in/brouer
next prev parent reply other threads:[~2016-09-13 7:07 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-09-08 4:52 [PATCH net-next] ipv4: accept u8 in IP_TOS ancillary data Eric Dumazet
2016-09-08 9:15 ` Jesper Dangaard Brouer
2016-09-08 13:31 ` Eric Dumazet
2016-09-13 7:07 ` Jesper Dangaard Brouer [this message]
2016-09-09 0:46 ` David Miller
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20160913090732.069417a2@redhat.com \
--to=brouer@redhat.com \
--cc=davem@davemloft.net \
--cc=eric.dumazet@gmail.com \
--cc=fusco@ntop.org \
--cc=maze@google.com \
--cc=netdev@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.