nixpkgs/nixos/modules/services/hardware/fwupd.nix

# fwupd daemon.

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

with lib;

let
  cfg = config.services.fwupd;
  originalEtc =
    let
      isRegular = v: v == "regular";
      listFiles = d: builtins.attrNames (filterAttrs (const isRegular) (builtins.readDir d));
      copiedDirs = [ "fwupd/remotes.d" "pki/fwupd" "pki/fwupd-metadata" ];
      originalFiles = concatMap (d: map (f: "${d}/${f}") (listFiles "${pkgs.fwupd}/etc/${d}")) copiedDirs;
      mkEtcFile = n: nameValuePair n { source = "${pkgs.fwupd}/etc/${n}"; };
    in listToAttrs (map mkEtcFile originalFiles);
  extraTrustedKeys =
    let
      mkName = p: "pki/fwupd/${baseNameOf (toString p)}";
      mkEtcFile = p: nameValuePair (mkName p) { source = p; };
    in listToAttrs (map mkEtcFile cfg.extraTrustedKeys);
in {

  ###### interface
  options = {
    services.fwupd = {
      enable = mkOption {
        type = types.bool;
        default = true;
        description = ''
          Whether to enable fwupd, a DBus service that allows
          applications to update firmware.
        '';
      };

      blacklistDevices = mkOption {
        type = types.listOf types.string;
        default = [];
        example = [ "2082b5e0-7a64-478a-b1b2-e3404fab6dad" ];
        description = ''
          Allow blacklisting specific devices by their GUID
        '';
      };

      blacklistPlugins = mkOption {
        type = types.listOf types.string;
        default = [];
        example = [ "udev" ];
        description = ''
          Allow blacklisting specific plugins
        '';
      };

      extraTrustedKeys = mkOption {
        type = types.listOf types.path;
        default = [];
        example = literalExample "[ /etc/nixos/fwupd/myfirmware.pem ]";
        description = ''
          Installing a public key allows firmware signed with a matching private key to be recognized as trusted, which may require less authentication to install than for untrusted files. By default trusted firmware can be upgraded (but not downgraded) without the user or administrator password. Only very few keys are installed by default.
        '';
      };
    };
  };


  ###### implementation
  config = mkIf cfg.enable {
    environment.systemPackages = [ pkgs.fwupd ];

    environment.etc = {
      "fwupd/daemon.conf" = {
        source = pkgs.writeText "daemon.conf" ''
          [fwupd]
          BlacklistDevices=${lib.concatStringsSep ";" cfg.blacklistDevices}
          BlacklistPlugins=${lib.concatStringsSep ";" cfg.blacklistPlugins}
        '';
      };
    } // originalEtc // extraTrustedKeys;

    services.dbus.packages = [ pkgs.fwupd ];

    services.udev.packages = [ pkgs.fwupd ];

    systemd.packages = [ pkgs.fwupd ];

    systemd.tmpfiles.rules = [
      "d /var/lib/fwupd 0755 root root -"
    ];
  };
}