This will set up a passthrough between the eth0
interface and the wan0
interface, with a VPN connection in-between.
You can then connect a machine to the ethernet port of the raspberrypi, and that machines network traffic will pass through the vpn tunnel on the raspberrypi.
The device connected to the ethernet plug of the PI should be set up with:
IP: 192.168.0.2
Mask: 255.255.255.0
Gateway: 192.168.0.1