openvpn-openssl Enable "iproute" option in OpenVPN make configuration

Hey Guys,

I recently run in a problem with the OpenVPN-OpenSSL package. I had to do some advanced routing to do: The routes that are pushed from a commercial VPN provider should be moved to a special routing table on the OpenVPN-Client side. The client is here my OpenWRT router. There is no working method to do that on standard OpenWRT.

I found out that it is possible to override the “ip”-command that OpenVPN is using to set the routing rules. With the “iproute”-option you can specify a program or script to act as the ip command. In a forum I found a great little example script that uses this option:

#!/bin/bash
if [ "$1" == "route" ] ; then
    ip $@ table vpn
else
    ip $@
fi

In the client configuration it is only necessary to point to the script:

iproute /etc/openvpn/vpn-iproute.sh

Unfortunately, the “iproute”-option needs to be set on compile time through the configure script. This option is currently not enabled in the openvpn-openssl package. It would be great if you could enable it. It would really help to do more advanced routing. Scripts that are using this method are very robust because changes that are coming from the server side are getting always implemented in the right way.

Start with the openvpn-openssl package's make configuration and inspect how configure options are enabled. Confirm that the iproute option is passed during the build, then verify the package builds successfully with the option enabled.