Re: [PATCH net-next 2/2] Special handling for IP & MPLS.

[Willem de Bruijn <willemdebruijn.kernel@gmail.com>]

On Wed, Oct 9, 2019 at 11:06 AM Willem de Bruijn
<willemdebruijn.kernel@gmail.com> wrote:
>
> On Wed, Oct 9, 2019 at 9:39 AM Martin Varghese
> <martinvarghesenokia@gmail.com> wrote:
> >
> > On Tue, Oct 08, 2019 at 12:09:49PM -0400, Willem de Bruijn wrote:
> > > On Tue, Oct 8, 2019 at 5:52 AM Martin Varghese
> > > <martinvarghesenokia@gmail.com> wrote:
> > > >
> > > > From: Martin <martin.varghese@nokia.com>
> > > >
> > >
> > > This commit would need a commit message.
> > >
> > > > Signed-off-by: Martin Varghese <martinvarghesenokia@gmail.com>
> > > >
> > > > Signed-off-by: Martin Varghese <martinvarghesenokia@gmail.com>
> > > > ---
> > > >  Documentation/networking/bareudp.txt | 18 ++++++++
> > > >  drivers/net/bareudp.c                | 82 +++++++++++++++++++++++++++++++++---
> > > >  include/net/bareudp.h                |  1 +
> > > >  include/uapi/linux/if_link.h         |  1 +
> > > >  4 files changed, 95 insertions(+), 7 deletions(-)
> > > >
> > > > diff --git a/Documentation/networking/bareudp.txt b/Documentation/networking/bareudp.txt
> > > > index d2530e2..4de1022 100644
> > > > --- a/Documentation/networking/bareudp.txt
> > > > +++ b/Documentation/networking/bareudp.txt
> > > > @@ -9,6 +9,15 @@ The Bareudp tunnel module provides a generic L3 encapsulation tunnelling
> > > >  support for tunnelling different L3 protocols like MPLS, IP, NSH etc. inside
> > > >  a UDP tunnel.
> > > >
> > > > +Special Handling
> > > > +----------------
> > > > +The bareudp device supports special handling for MPLS & IP as they can have
> > > > +multiple ethertypes.
> > >
> > > Special in what way?
> > >
> > The bareudp device associates a L3 protocol (ethertype) with a UDP port.
> > For some protocols like MPLS,IP there exists multiplle ethertypes.
> > IPV6 and IPV4 ethertypes for IP and MPLS unicast & Multicast ethertypes for
> > MPLS. There coud be use cases where both MPLS unicast and multicast traffic
> > need to be tunnelled using the same bareudp device.Similarly for ipv4 and ipv6.
>
> IP is already solved. I would focus on MPLS.
>
> Also, the days where IPv6 is optional (and needs IPv4 enabled) are
> behind us, really.

Ah sorry, there is nothing stopping someone from creating an
ETH_P_IPV6 only device before this path.

> Maybe just let the admin explicitly specify MPLS unicast, multicast or
> both, instead of defining a new extended label.

Deriving the inner protocol type from the outer protocol mode sounds
fine, indeed.