uvms/profiles/vsock-connect-guest.nix

{
  options,
  config,
  lib,
  ...
}:
let
  mkIfGuest = import ../lib/mkIfMicrovmGuest.nix { inherit options config lib; };
in
{
  config = lib.mkMerge [
    (mkIfGuest {
      microvm.cloud-hypervisor.extraArgs = [
        "--vsock"
        "cid=4,socket=vsock.sock"
      ];
    })
    {
      # Somehow, sshd calls to PAM with PAM_RHOST="UNKNOWN",
      # prompting a slow DNS look-up each time...
      #
      # https://mastodon.acm.org/@nobody/115108458851355328
      # https://github.com/linux-pam/linux-pam/issues/885#issuecomment-3030698895
      networking.hosts."100::" = [ "UNKNOWN" ];
      boot.initrd.extraFiles = lib.optionalAttrs config.boot.initrd.network.ssh.enable {
        "/etc/hosts" = { inherit (config.environment.etc.hosts) source; };
      };
    }
  ];
}