NATBreaker

IPtable scripts for forwarding traffic through a tunnel interface.

After initializing VPN (Using Openvpn), these scripts have a server and a client version that will forward and transmit packet inside a NAT if a user does not have an external IPv4 address. Requires a VPS of some sort with a dedicated IPv4 address. Examples include 443 and 32400.

NOTES eth0 is the name of your primary interface. I am using an OpenVZ container from RamNode which uses venet0

Make sure:
net.ipv4.ip_forward = 1
is listed in /etc/sysctl.conf

While this does not cover setting up OpenVPN or another tunnel service, I am using https://github.com/kylemanna/docker-openvpn/ for openvpn via Docker in my VPS (OpenVZ container hosted by RamNode).

I am using https://github.com/dperson/openvpn-client for my internal client.

Server Config:

Set your server openvpn IP address and the destination openvpn IP address (The Kylemanna container issues a 192.168.255.X). Also set the ports you are forwarding in the array:

#for ports 443 and 32400 through the tunnel
ports=( 443 32400 )

Client Config:

Set the same client and server OpenVPN IP addresses, as well as the same destination ports. Additionally, though, you need to direct the packets to their final destinations. The destinations array should be in the same order as your ports array.

So for:

ports=( 443 32400 )
destinations=( 17.181.30.18 17.181.30.10 )

443 will get routed to the internal network of 172.20.30.18 and 32400 will get routed to 172.20.30.10.