-I VPN_PASSTHROUGH -i INTERFACE -o lbr0 -p tcp --dport 1723 -j ACCEPT
-I VPN_PASSTHROUGH -i INTERFACE -o lbr0 -p 47 -j ACCEPT
-I VPN_PASSTHROUGH -i lbr0 -o INTERFACE -p tcp --dport 1723 -j ACCEPT
-I VPN_PASSTHROUGH -i lbr0 -o INTERFACE -p 47 -j ACCEPT