Setup OpenVPN Client on OpenWRT

In an attempt to secure my internet connection, I setup OpenVPN on a OpentWRT enabled router: a good old Linksys WRT54G v3.1.

The best firmware for this router seems to be OpenWRT Backfire 10.03.1 (brcm-2.4) (LuCI 0.10.0) (also in attachment of this page). The upgrade is very easy from the Linksys or (DD-WRT) web GUI as you just need to follow the regular upgrade procedure.

After the router reboot, I put a password which effectively disabled telnet but enabled SSH on the server. From there, I SSH to the server:

ssh 192.168.1.1 -l root

It's now time to install OpenVPN and the OpenVPN LuCI GUI:

opkg update
opkg install openvpn luci-app-openvpn

However I didn't use LuCI to setup the VPN -- it was too buggy. I copied the config files from my PC to the router using SCP:

scp /etc/openvpn/* root@192.168.1.1:/etc/openvpn/

I then tweaked the openVPN "main" config file (to remain compatible with LuCI) at /etc/config/openvpn by inserting the following and putting the rest in comments (with #)

config 'openvpn' 'IPredator'
           option 'config' /etc/openvpn/IPredator.conf

In LuCI should look like:

I ran openvpn manually to check its status:

openvpn --configfile /etc/openvpn/IPredator.conf

Everything went fine. Next step is to configure the firewall by creating a new zone and forwarding internet traffic from lan to it:

in Luci go Network → Interfaces
Create new Interface
Add new interface → VPN → Protocol = Unmanaged on Tab Physical Settings click Ehternet Adapter: tun0 and Save

Go to Network → Firewall → General Settings
Add new zone
- Name: vpn
- Input: accept
- Output: accept
- Forward: reject
- Masquerading: ☑
- MSS clamping: ☑
In wan zone
- Disable masquerading and MSS clamping
Lan zone must forward to vpn zone