machines/mermet/security.nix

   1 { pkgs, lib, config, machineName, ... }:
   2 let
   3   inherit (config.security) gnupg;
   4   rootKey = "root/key";
   5   initrdKey = "initrd/ssh.key";
   6   keygrip = "89F52A879E0019A966503AFFDE72EEA84CDFA3A7";
   7 in
   8 {
   9 imports = [
  10   <nixpkgs/nixos/modules/profiles/hardened.nix>
  11 ];
  12 security.gnupg.store = builtins.getEnv "PASSWORD_STORE_DIR" + "/machines/${machineName}";
  13 services.openssh.extraConfig = ''
  14   StreamLocalBindUnlink yes
  15 '';
  16 installer.ssh-nixos = {
  17   PATH = [pkgs.gnupg pkgs.openssh];
  18   script = lib.mkMerge [
  19     (lib.mkBefore ''
  20       # Send the SSH key of the initrd
  21       gpg --decrypt '${gnupg.store}/${initrdKey}.gpg' |
  22       ssh '${config.installer.ssh-nixos.target}' \
  23       install -D -m 400 -o root -g root /dev/stdin /root/${initrdKey}
  24     '')
  25     (lib.mkBefore ''
  26       ssh '${config.installer.ssh-nixos.target}' \
  27       "gpg-connect-agent --no-autostart --homedir /var/lib/gnupg 'keyinfo --list' /bye 2>&1" |
  28       grep -qx -e "gpg-connect-agent: no gpg-agent running in this session" \
  29                -e "S KEYINFO ${keygrip} . . . 1 .*" || {
  30         # Send the rootKey
  31         gpg --decrypt '${gnupg.store}/${rootKey}.pass.gpg' |
  32         gpg --batch --pinentry-mode loopback --passphrase-fd 0 --export-secret-subkeys @root@${machineName} |
  33         ssh '${config.installer.ssh-nixos.target}' \
  34         gpg --no-autostart --homedir /var/lib/gnupg --no-autostart --batch --pinentry-mode loopback --import
  35
  36         # Send the rootKey's passphrase
  37         gpg --decrypt '${gnupg.store}/${rootKey}.pass.gpg' |
  38         ssh '${config.installer.ssh-nixos.target}' \
  39         gpg-preset-passphrase --homedir /var/lib/gnupg --preset ${keygrip}
  40       }
  41     '')
  42   ];
  43 };
  44 boot.initrd.network.ssh.hostKeys = [ "/root/${initrdKey}" ];
  45 }