Re: [devel-ipsec] [PATCH ipsec-next, v4] xfrm: support sending NAT keepalives in ESP in UDP states

[Antony Antony <antony.antony@secunet.com>]

On Mon, May 27, 2024 at 20:29:14 -0700, Eyal Birger via Devel wrote:
> Add the ability to send out RFC-3948 NAT keepalives from the xfrm stack.
> 
> To use, Userspace sets an XFRM_NAT_KEEPALIVE_INTERVAL integer property when
> creating XFRM outbound states which denotes the number of seconds between
> keepalive messages.
> 
> Keepalive messages are sent from a per net delayed work which iterates over
> the xfrm states. The logic is guarded by the xfrm state spinlock due to the
> xfrm state walk iterator.
> 
> Possible future enhancements:
> 
> - Adding counters to keep track of sent keepalives.
> - deduplicate NAT keepalives between states sharing the same nat keepalive
>   parameters.
> - provisioning hardware offloads for devices capable of implementing this.
> - revise xfrm state list to use an rcu list in order to avoid running this
>   under spinlock.
> 
> Suggested-by: Paul Wouters <paul.wouters@aiven.io>
> Signed-off-by: Eyal Birger <eyal.birger@gmail.com>

Tested-by: Antony Antony <antony.antony@secunet.com>

thanks,
-antony