ip6tables -t nat -A POSTROUTING -s fd42:42:42:42::/112 -o $NIC -j MASQUERADE
ip6tables -A INPUT -i tun0 -j ACCEPT
ip6tables -A FORWARD -i $NIC -o tun0 -j ACCEPT
ip6tables -A FORWARD -i tun0 -o $NIC -j ACCEPT