Re: [PATCH] netfilter: add CHECKSUM target

From: Michael S. Tsirkin
Date: Sun Jul 11 2010 - 05:27:54 EST


On Fri, Jul 09, 2010 at 03:18:14PM +0800, Herbert Xu wrote:
> On Fri, Jul 09, 2010 at 01:29:13AM +0300, Michael S. Tsirkin wrote:
> > This adds a `CHECKSUM' target, which can be used in the iptables mangle
> > table.
> >
> > You can use this target to compute and fill in the checksum in
> > an IP packet that lacks a checksum. This is particularly useful,
> > if you need to work around old applications such as dhcp clients,
> > that do not work well with checksum offloads, but don't want to
> > disable checksum offload in your device.
> >
> > The problem happens in the field with virtualized applications.
> > For reference, see Red Hat bz 605555, as well as
> > http://www.spinics.net/lists/kvm/msg37660.html
> >
> > Typical expected use (helps old dhclient binary running in a VM):
> > iptables -A POSTROUTING -t mangle -p udp --dport 68 -j CHECKSUM
> > --checksum-fill
> >
> > Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx>
>
> I'd think that this target would be protocol-agnostic, no?

Meaning it should go into net/netfilter/? Will do.

> Cheers,
> --
> Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
> Home Page: http://gondor.apana.org.au/~herbert/
> PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
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