I want to allow an application on a Windows 7 Professional System to only be accessible through the OpenVPN TAP adapter by configuring the Windows Firewall accordingly. Unfortunately I cannot find an option therefor. I found out that it is possible to allow applications on certain NIC-types, but the OpenVPN adapter is recognized as an Ethernet adapter and I do not want the application to be accessible through ethernet adapters other than the TAP adapter. I currently circumvent this issue by allowing the application on all adapters but only from a certain source network. However this network might change in the future whereas the TAP's name might not. For better understanding, I'd like to have an equivalent to the iptables rule:
iptables -I INPUT -i tun0 -p tcp --dport 5900 -j ACCEPT
Where the magic word is -i tun0.