{ config, pkgs, ... }:
let

in
{
   networking.firewall = {
    # if packets are still dropped, they will show up in dmesg
    logReversePathDrops = true;
    # wireguard trips rpfilter up
    extraCommands = ''
      ip46tables -t mangle -I nixos-fw-rpfilter -p udp -m udp --sport 51820 -j RETURN
      ip46tables -t mangle -I nixos-fw-rpfilter -p udp -m udp --dport 51820 -j RETURN
    '';
    extraStopCommands = ''
      ip46tables -t mangle -D nixos-fw-rpfilter -p udp -m udp --sport 51820 -j RETURN || true
      ip46tables -t mangle -D nixos-fw-rpfilter -p udp -m udp --dport 51820 -j RETURN || true
    '';

    allowedUDPPorts = [ 51820 ];
  };
}