#!/bin/sh
HOST=REMOTE_PARTY_ADDRESS
HOST_PORT=22
TUN_LOCAL=0   # tun device number here.
TUN_REMOTE=0  # tun device number there
IP_LOCAL=192.168.111.2 # IP Address for tun here
IP_REMOTE=192.168.111.1 # IP Address for tun there.
IP_MASK=30 # Mask of the ips above.
NET_REMOTE=192.168.0.0/16 # Network on the other side of the tunnel
NET_LOCAL=192.168.8.0/24  # Network on this side of the tunnel

echo "Starting VPN tunnel ..."
modprobe tun
ssh -w ${TUN_LOCAL}:${TUN_REMOTE} -f ${HOST} -p ${HOST_PORT} "
ip addr add ${IP_REMOTE}/${IP_MASK} dev tun${TUN_REMOTE}
&& ip link set tun${TUN_REMOTE} up
&& ip route add ${NET_LOCAL} via ${IP_LOCAL}
&& true"
sleep 3
ip addr add ${IP_LOCAL}/${IP_MASK} dev tun${TUN_LOCAL}
ip link set tun${TUN_LOCAL} up
ip route add ${NET_REMOTE} via ${IP_REMOTE}
echo "... done."