[RFC PATCH net-next 0/3] L3 RX handler

[David Ahern <dsa@cumulusnetworks.com>]

Currently the VRF driver registers an Rx handler for enslaved devices.
The handler switches the skb->dev to the VRF device and sends it back for
another pass. While this works fine a side effect is that it bypasses
netfilter with the skb set to the original device.

Looking at how to provide that feature a few options come to mind:
1. Have the rx handler in the VRF driver duplicate some of the processing
   of ip_rcv up to the NF_HOOK and then switch the skb->dev to vrf device.

2. Run NF_HOOK in ip_rcv twice -- once with orig_dev and then again for dev.

3. Introduce an L3 rx-handler that provides the option of hooking packets
   at L3 rather than the current backlog loop.

This RFC looks at option 3. I wanted to get opinions on the approach
versus other options.

David Ahern (3):
  net: Introduce L3 RX Handler
  net: Add L3 Rx handler to IPv4 processing
  net: Change VRF driver to use the new L3 RX handler

 drivers/net/vrf.c         | 32 +++++++++------------------
 include/linux/netdevice.h |  6 ++++++
 net/core/dev.c            | 55 ++++++++++++++++++++++++++++++++++++++---------
 net/ipv4/ip_input.c       | 32 +++++++++++++++++++++++++--
 4 files changed, 91 insertions(+), 34 deletions(-)

-- 
1.9.1