#!/bin/sh -x

if [ "$USER" != "root" -o "$1" != "sudo" ]; then
  exec sudo -p "Password for $0:" $0 sudo $1
fi

[ "$1" = "sudo" ] && shift

/sbin/ifconfig $1 172.20.0.1
iptables -t nat -A POSTROUTING -s 172.20.0.1/24 -o eth0 -j MASQUERADE
sysctl -w net.ipv4.ip_forward=1