nixcfg/modules/gnome/fingerprint.nix

{ config, pkgs, ... }:

{
    # Need to change the order pam loads its modules
    # to get proper fingerprint behavior on GDM and the lockscreen.
    security.pam.services.login.fprintAuth = false;
    security.pam.services.gdm-fingerprint = lib.mkIf (config.services.fprintd.enable) {
    text = ''
        auth       required                    pam_shells.so
        auth       requisite                   pam_nologin.so
        auth       requisite                   pam_faillock.so      preauth
        auth       required                    ${pkgs.fprintd}/lib/security/pam_fprintd.so
        auth       optional                    pam_permit.so
        auth       required                    pam_env.so
        auth       [success=ok default=1]      ${pkgs.gnome.gdm}/lib/security/pam_gdm.so
        auth       optional                    ${pkgs.gnome.gnome-keyring}/lib/security/pam_gnome_keyring.so

        account    include                     login

        password   required                    pam_deny.so

        session    include                     login
        session    optional                    ${pkgs.gnome.gnome-keyring}/lib/security/pam_gnome_keyring.so auto_start
    '';
    };
}