infra/hosts/wob-vpn-gw/netboot.nix

{ config, lib, pkgs, nodes, modulesPath, ... }:

# The way the connection is established is specific to the wob01 site and the Intel S2600KPR blades.
# Proper netboot is not possible, because while the blades and the APU board (which is the netboot
# server here) are in the same L2 network, the uplink connection of each blade is an LACP LAG,
# meaning that the switch on the other side will only enable the port if it sees valid LACP packets.
# We work around this by presenting a virtual floppy drive using the "IUSB" protocol of the BMC.
# This virtual floppy drive contains an per-blade customized initramfs which will initialize the
# network connection including IP configuration and load the actual image off hydra.

let
  netboot-server-ip = "2a01:584:11::2";
  netbootNodes = lib.filterAttrs (_: node: node.config.bagel.baremetal.builders.enable && node.config.bagel.baremetal.builders.netboot) nodes;
in {

  assertions = [
    {
      assertion = !(lib.elem 443 config.networking.firewall.allowedTCPPorts);
      message = ''
        Port 443 is in networking.firewalls.allowedTCPPorts, but should be only manually
        allowed for specific IPs and source ports in ${builtins.toJSON __curPos}
      '';
    }
  ];

  systemd.services = lib.mapAttrs' (nodename: node: let
    bmcIp = "192.168.1.${toString (node.config.bagel.baremetal.builders.num * 4 + 2)}";
    notipxe = node.config.system.build.notipxe.config.system.build.usbImage;
  in lib.nameValuePair "iusb-spoof-${nodename}" {
    wantedBy = [ "multi-user.target" ];
    serviceConfig = {
      Restart = "always";
    };
    script = ''
      AUTH_TOKEN=$(${pkgs.iusb-spoof}/bin/make-token ${bmcIp})
      exec ${pkgs.iusb-spoof}/bin/iusb-spoof -r ${bmcIp} 5123 $AUTH_TOKEN ${notipxe}
    '';
  }) netbootNodes;

  # Since the builders are stateless, they can not store their ssh hostkeys
  networking.firewall.allowedTCPPorts = [ 80 ]; # for ACME
  networking.firewall.extraInputRules = ''
    ip6 saddr 2a01:584:11::/64 tcp sport < 1024 tcp dport 443 accept;
  '';
  services.nginx = {
    enable = true;
    virtualHosts."vpn-gw.wob01.infra.forkos.org" = {
      enableACME = true;
      forceSSL = true;
      locations = lib.mapAttrs' (nodename: node: let
        ip = "2a01:584:11::1:${toString node.config.bagel.baremetal.builders.num}";
      in lib.nameValuePair "/${nodename}/" {
        root = "/var/www";
        extraConfig = ''
          allow ${ip};
          deny all;
        '';
      }) netbootNodes;
    };
  };
}