jre-phoenix - 2014-01-04

I assume that all forwarded traffic is coming from openvpn, but nowhere else. Thus I assume that you want to allow all forwarded traffic.

Then
WHITE_IP_FWD="10.8.0.0/24"
or
WHITE_IP_FWD="10.8.0.6"
should do the trick for you.

Further for your purposes you don't need to/should not set the INTERFACES,
WHITE_IP_OUT or WHITE_IP_IN settings.

Although there may well be another solution utilizing only INTERFACES.

Greets