VPN split tunneling

Thanks guys for the suggestions.

  • dscp packets
    -> I have searched for a while, and I think it is not possible to make the browser, nor the OS, mark the packets with dscp.

  • use ssh server as socks proxy for the web browser, and then route local traffic via vpn
    -> I am a little uneasy about that, as I wonder if there might be currently existing local traffic. If that's the case, that traffic will go via the vpn, which I want to avoid (I need to have only the browser traffic go through the vpn)

  • the original idea of having a proxy running on the router, and having that proxy connect to the VPN
    -> I was not able to find how to select a specific network interface in the configuration of the proxy. However, maybe I can put the proxy at a specific IP, and then inside /etc/config/firewall maybe I can redirect all the traffic coming from that specific IP to the vpn interface?
    If that is not possible to do this with a specific IP, then maybe I use a specific port, or specific zone instead?