This patch introduces netfilter hooks for solving the problem that
conntrack couldn't record both inner flows and outer flows.
This patch also introduces a new sysctl toggle for enabling lightweight
tunnel netfilter hooks.
Signed-off-by: Ryoga Saito <contact@proelbtn.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Ryoga Saito