nixpkgs/nixos/tests/systemd-initrd-networkd-ssh.nix

import ./make-test-python.nix ({ lib, ... }: {
  name = "systemd-initrd-network-ssh";
  meta.maintainers = [ lib.maintainers.elvishjerricco ];

  nodes = {
    server = { config, pkgs, ... }: {
      testing.initrdBackdoor = true;
      boot.initrd.systemd.enable = true;
      boot.initrd.systemd.contents."/etc/msg".text = "foo";
      boot.initrd.network = {
        enable = true;
        ssh = {
          enable = true;
          authorizedKeys = [ (lib.readFile ./initrd-network-ssh/id_ed25519.pub) ];
          port = 22;
          hostKeys = [ ./initrd-network-ssh/ssh_host_ed25519_key ];
        };
      };
    };

    client = { config, ... }: {
      environment.etc = {
        knownHosts = {
          text = lib.concatStrings [
            "server,"
            "${
              toString (lib.head (lib.splitString " " (toString
                (lib.elemAt (lib.splitString "\n" config.networking.extraHosts) 2))))
            } "
            "${lib.readFile ./initrd-network-ssh/ssh_host_ed25519_key.pub}"
          ];
        };
        sshKey = {
          source = ./initrd-network-ssh/id_ed25519;
          mode = "0600";
        };
      };
    };
  };

  testScript = ''
    start_all()

    def ssh_is_up(_) -> bool:
        status, _ = client.execute("nc -z server 22")
        return status == 0

    client.wait_for_unit("network.target")
    with client.nested("waiting for SSH server to come up"):
        retry(ssh_is_up)

    msg = client.succeed(
        "ssh -i /etc/sshKey -o UserKnownHostsFile=/etc/knownHosts server 'cat /etc/msg'"
    )
    assert "foo" in msg

    server.switch_root()
    server.wait_for_unit("multi-user.target")
  '';
})