A simple tunnel

this is a simple and fast tunnel using pre-shared keys for encryption. it tunnels both ipv4 and ipv6 packets into a ipv4 tunnel. this program uses the ip and iptables & ip6tables commands to manipulate ip addresses, routes and ip tables, so it requires the user to have corresponding capabilities, or simply run as root. this program uses the crypto lib for encryption.

build

$ make all

usage

start the server on a machine which could forward packets:

$ ./tun -g > tun.key
$ ./tun

copy tun.key to the local machine(the key is pre-shared, e.g. by some other secure means) start the client locally:

$ ./tun -s <server address>

now all ip packets should go through the tunnel.

notes

this is a quick work, not very clean, but works well enough for my own use.