nixos/server/deluge/default.nix

{
  lib,
  config,
  pkgs,
  ...
}:
{
  options.server.deluge.enable = lib.mkEnableOption "Enable deluge torrent client";

  config = lib.mkIf config.server.deluge.enable {
    services.deluge = {
      enable = true;
      web.enable = true;
    };

    environment.systemPackages = with pkgs; [ libnatpmp ];

    networking.firewall.allowedTCPPorts = [ 8112 ];

    # creating network namespace
    systemd.services."netns@" = {
      description = "%I network namespace";
      before = [ "network.target" ];
      serviceConfig = {
        Type = "oneshot";
        RemainAfterExit = true;
        ExecStart = "${pkgs.iproute2}/bin/ip netns add %I";
        ExecStop = "${pkgs.iproute2}/bin/ip netns del %I";
      };
    };

    systemd.services.wg-port-opener = {
      description = "port opener for protonvpn";
      bindsTo = [ "netns@wg.service" ];
      requires = [ "network-online.target" ];
      after = [ "netns@wg.service" ];
      serviceConfig = {
        Type = "exec";
        NetworkNamespacePath = [ "/var/run/netns/wg" ];
        ExecStart =
          with pkgs;
          writers.writeBash "port-opening" ''
            while true; do
              date;
              ${libnatpmp}/bin/natpmpc -a 1 0 udp 60 -g 10.2.0.1 || { echo -e "ERROR with natpmpc udp command \a" ; break ; };
              ${libnatpmp}/bin/natpmpc -a 1 0 tcp 60 -g 10.2.0.1 || { echo -e "ERROR with natpmpc tcp command \a" ; break ; };
              sleep 45;
            done;
          '';
      };
    };

    # setting up wireguard interface within network namespace
    systemd.services.wg = {
      description = "wg network interface";
      bindsTo = [ "netns@wg.service" ];
      requires = [ "network-online.target" ];
      after = [ "netns@wg.service" ];
      serviceConfig = {
        Type = "oneshot";
        RemainAfterExit = true;
        ExecStart =
          with pkgs;
          writers.writeBash "wg-up" ''
            ${iproute2}/bin/ip link add wg0 type wireguard
            ${iproute2}/bin/ip link set wg0 netns wg
            ${iproute2}/bin/ip -n wg address add 10.2.0.2/32 dev wg0
            # ${iproute2}/bin/ip -n wg -6 address add fc00:bbbb:bbbb:bb01::a:1674/128 dev wg0
            ${iproute2}/bin/ip netns exec wg \
              ${wireguard-tools}/bin/wg setconf wg0 /root/proton.conf
            ${iproute2}/bin/ip -n wg link set wg0 up
            # need to set lo up as network namespace is started with lo down
            ${iproute2}/bin/ip -n wg link set lo up
            ${iproute2}/bin/ip -n wg route add default dev wg0
            ${iproute2}/bin/ip -n wg -6 route add default dev wg0
          '';
        ExecStop =
          with pkgs;
          writers.writeBash "wg-down" ''
            ${iproute2}/bin/ip -n wg route del default dev wg0
            ${iproute2}/bin/ip -n wg -6 route del default dev wg0
            ${iproute2}/bin/ip -n wg link del wg0
          '';
      };
    };

    # binding deluged to network namespace
    systemd.services.deluged.bindsTo = [ "netns@wg.service" ];
    systemd.services.deluged.requires = [
      "network-online.target"
      "wg.service"
    ];
    systemd.services.deluged.serviceConfig.NetworkNamespacePath = [ "/var/run/netns/wg" ];

    systemd.services.deluge-port-setter = {
      description = "sets deluge ports";
      bindsTo = [ "netns@wg.service" ];
      requires = [ "network-online.target" ];
      after = [ "deluged.service" ];
      serviceConfig = {
        Type = "oneshot";
        User = "deluge";
        RemainAfterExit = true;
        NetworkNamespacePath = [ "/var/run/netns/wg" ];
        ExecStart =
          with pkgs;
          writers.writeBash "deluge-ports" ''
            TCP=($(${libnatpmp}/bin/natpmpc -a 1 0 tcp 60 -g 10.2.0.1 2> /dev/null | grep Mapped))
            TCP_PORT=''${TCP[3]}
            UDP=($(${libnatpmp}/bin/natpmpc -a 1 0 udp 60 -g 10.2.0.1 2> /dev/null | grep Mapped))
            UDP_PORT=''${UDP[3]}
            echo "The ports are"
            echo "TCP: $TCP_PORT"
            echo "UDP: $UDP_PORT"
            PORTS="($TCP_PORT, $UDP_PORT)"
            ${deluge}/bin/deluge-console "config -s random_port false; config -s listen_ports $PORTS"

            exit 0
          '';
      };
    };

    # allowing delugeweb to access deluged in network namespace, a socket is necesarry
    systemd.sockets."proxy-to-deluged" = {
      enable = true;
      description = "Socket for Proxy to Deluge Daemon";
      listenStreams = [ "58846" ];
      wantedBy = [ "sockets.target" ];
    };

    # creating proxy service on socket, which forwards the same port from the root namespace to the isolated namespace
    systemd.services."proxy-to-deluged" = {
      enable = true;
      description = "Proxy to Deluge Daemon in Network Namespace";
      requires = [
        "deluged.service"
        "proxy-to-deluged.socket"
      ];
      after = [
        "deluged.service"
        "proxy-to-deluged.socket"
      ];
      unitConfig = {
        JoinsNamespaceOf = "deluged.service";
      };
      serviceConfig = {
        User = "deluge";
        Group = "deluge";
        ExecStart = "${pkgs.systemd}/lib/systemd/systemd-socket-proxyd --exit-idle-time=5min 127.0.0.1:58846";
        PrivateNetwork = "yes";
      };
    };
  };
}