[strongSwan] anti replay notification related

[Martin Willi]

> We tested and found that setting "charon.replay_window" to zero doesn't
> disable the anti-replay. I think it defaults to "32" packet window
> size.

I think that should work, but only when using the kernel-netlink kernel
backend. charon just forwards this value to the kernel, it is not
enforced by strongSwan itself.

Can you double-check that "ip xfrm state" shows a replay window of 0? If
yes, you might check how your kernel handles a replay window of zero.

Regards
Martin