OK, sounds good. Do you think you need the ability to inject payloads of a specific length or content? It's easy to, for example, always generate 64 bytes of payload, but it would be a little more challenging to plumb through extra data or metadata.
On Mon, Jan 15, 2018 at 01:48:10PM +1300, Brad Cowie wrote: > Hi Ben, > > We looked a bit closer at this problem, and turns out the packet header > size we were getting back from Ryu wasn't what we were expecting. We're now > calculating this correctly ourselves (instead of relying on Ryu) which > removes the need for disabling the IP header length check in the tutorial > (I've send another patch towards d...@openvswitch.org that does this). > > As for being able to inject payload into ofproto/trace generated packets I > think this would be quite useful for folks like us. We are looking at > moving our test suite to using ofproto/trace to generate packets (instead > of scapy) for throwing at test scenarios because it's considerably more > lightweight and we are already using openvswitch as the core of our test > suite. > > Brad > > On 9 January 2018 at 05:51, Ben Pfaff <b...@ovn.org> wrote: > > > [dropping OP, who probably doesn't care] > > > > On Sat, Jan 06, 2018 at 12:07:09PM +1300, Brad Cowie wrote: > > > What happened is that in faucet 1.6.12 we added a bunch of new packet > > > handling sanity checks to help improve security of faucet's packet > > > handling. Packets made by ofproto/trace -generate will have a zero-length > > > payload which trips some of our sanity checks which will cause us to drop > > > the packet. > > > > If OVS generated a packet with some nonzero size payload, would that fix > > the problem? It's easy for us to change the details, we would just add > > some code to flow_compose_l4() in lib/flow.c to put some L7 data into > > the UDP packet. > > > > I suspect that changing the tutorial from using UDP to TCP might also > > work around the issue? After all, TCP packets with empty payloads are > > pretty common, at least (off the top of my head) if they have SYN or FIN > > or RST attached. > > _______________________________________________ discuss mailing list disc...@openvswitch.org https://mail.openvswitch.org/mailman/listinfo/ovs-discuss