On Fri, Apr 22, 2016 at 2:27 PM, Jiri Benc <jb...@redhat.com> wrote: > On Fri, 22 Apr 2016 14:07:01 -0700, pravin shelar wrote: >> On Fri, Apr 22, 2016 at 10:44 AM, Jiri Benc <jb...@redhat.com> wrote: >> > For ipgre interfaces in collect metadata mode, receive also traffic with >> > encapsulated Ethernet headers. The lwtunnel users are supposed to sort this >> > out correctly. This allows to have mixed Ethernet + L3-only traffic on the >> > same lwtunnel interface. >> > >> How user is suppose to sort out the type of packet? whether it is L2 or L3. > > By skb->protocol, of course. Will be ETH_P_TEB if the inner packet was > Ethernet. There's no problem with this, for lwtunnels used with encap > routes, such packets are just discarded (which is the expected > behavior), as there's no protocol handler for ETH_P_TEB. More clever > lwtunnel users (such as openvswitch) can process the packets. This is > important in order to have a single tunnel interface for everything. >
But skb->protocol is not set to ETH_P_TEB anywhere in ip-gre module. Am I missing something? >> Is it fine to receive L2 packet over L3 device? >> At least ip_tunnel_rcv() is not ready to handle such packet. > > I don't see why. Could you please elaborate? Seems safe to me. The > desired result is skb->protocol == htons(ETH_P_TEB), network header(!) > pointing to the start of the Ethernet frame (because we're tunneling > Ethernet via ARPHRD_IPGRE interface, there's no L2 header to have), mac > header not being set. > ip_tunnel_rcv() checks device type (tunnel->dev->type) to perform ethernet specific processing on packet. I think that should be changed to check packet type.
