Re: [PATCHv2 net-next] {ipv4,xfrm}: Introduce xfrm_tunnel_notifier for xfrm tunnel mode callback

[Steffen Klassert <steffen.klassert@secunet.com>]

On Wed, Aug 28, 2013 at 03:09:40PM +0800, Fan Du wrote:
> Some thoughts on IPv4 VTI implementation:
> 
> The connection between VTI receiving part and xfrm tunnel mode input process
> is hardly a "xfrm_tunnel", xfrm_tunnel is used in places where, e.g ipip/sit
> and xfrm4_tunnel, acts like a true "tunnel" device.
> 
> In addition, IMHO, VTI doesn't need vti_err to do something meaningful, as all
> VTI needs is just a notifier to be called whenever xfrm_input ingress a packet
> to update statistics.
> 
> A IPsec protected packet is first handled by protocol handlers, e.g AH/ESP,
> to check packet authentication or encryption rightness. PMTU update is taken
> care of in this stage by protocol error handler.
> 
> Then the packet is rearranged properly depending on whether it's transport
> mode or tunnel mode packed by mode "input" handler. The VTI handler code
> takes effects in this stage in tunnel mode only. So it neither need propagate
> PMTU, as it has already been done if necessary, nor the VTI handler is
> qualified as a xfrm_tunnel. 
> 
> So this patch introduces xfrm_tunnel_notifier and meanwhile wipe out vti_err
> code.
> 
> Signed-off-by: Fan Du <fan.du@windriver.com>
> Cc: Steffen Klassert <steffen.klassert@secunet.com>
> Cc: David S. Miller <davem@davemloft.net>
> Reviewed-by: Saurabh Mohan <saurabh.mohan@vyatta.com>

Applied to ipsec-next, thanks a lot!