[ovs-dev] adding an option for GRE tunneling without an Ethernet header
thomas.morin at orange.com
thomas.morin at orange.com
Fri Feb 28 10:31:04 UTC 2014
Hi Lori, Praveen,
Thank you for the pointer on l3 vports.
I'll have a look at this.
2014-02-27, Lori Jakab:
> Hi Thomas,
> I'm the original contributor of the LISP tunneling code. Since it was
> originally accepted, I have been working on a series of patches to
> enable more generic support for layer 3 packets in OVS. While I was
> doint it with LISP in mind, I did consider enabling IP-over-GRE at some
> point. It's great that you're interested in this too!
> Instead of this patch, would you consider implementing IP-over-GRE
> support based on my patch series? I will soon post a v3 of it for
> review, but you can always find the lastest version in my Github repo:
> On 2/27/14, 7:16 PM, thomas.morin at orange.com wrote:
>> Currently, OVS GRE tunnels use Ethertype 6558 and the GRE packets
>> produced by OVS hence always are xxx-over-Ethernet-over-GRE.
>> Symmetrically OVS expects received GRE packets to be of the same
>> ethertype and carry an Ethernet payload.
>> I have written the included patch, which does the following:
>> - add a "noeth" option for a GRE tunnel, so that the Ethernet header is
>> stripped before GRE encapsulation (the option, of course, defaults to
>> the current behavior)
>> - on reception, recreates a fake Ethernet header if the ethertype of the
>> received packet is not 6558 -- this behavior is similar to what the LISP
>> tunneling code does
>> Note that, in both cases, the code takes care of preserving correct
>> As a result, this patch allows to setup GRE tunnels to interconnect OVS
>> with network devices doing a usual x-over-GRE approach such as IP/MPLS
>> The patch builds and passes unit tests.
>> It has been tested to confirm with a packet capture that:
>> - with the option set on a tunnel, the GRE packets from this tunnel are
>> send and received as expected
>> - for a tunnel without this option, or we the option disabled, the
>> current behavior is preserved
>> - documentation and unit test are missing, but I'll be happy to
>> contribute these later
>> - I not an experimented C coder, please be kind :)
>> - some parts of the code are a bit of a guess work from me: I'm unsure
>> of what needs to be done for GSO (possibly it can be done later?), or if
>> re-checksumming is really needed after recreating a fake Ethernet header
>> I'd be happy to have comments on the approach and on the patch and to
>> take them into account.
>> Thank you,
>> datapath/datapath.c | 1
>> datapath/flow_netlink.c | 7 +++
>> datapath/linux/compat/include/net/gre.h | 4 +
>> datapath/linux/compat/include/net/ip_tunnels.h | 1
>> datapath/vport-gre.c | 57
>> include/linux/openvswitch.h | 1
>> lib/flow.c | 2
>> lib/flow.h | 1
>> lib/netdev-vport.c | 9 +++
>> lib/netdev.h | 1
>> lib/odp-util.c | 11 ++++
>> lib/odp-util.h | 3 -
>> ofproto/tunnel.c | 7 ++-
>> 13 files changed, 101 insertions(+), 4 deletions(-)
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a l'expediteur et le detruire ainsi que les pieces jointes. Les messages electroniques etant susceptibles d'alteration,
Orange decline toute responsabilite si ce message a ete altere, deforme ou falsifie. Merci.
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