private static final byte[] APPCONTEXT_300 = toCBytes("SmbRpc");
    private static final byte[] APPLABEL_300 = toCBytes("SMB2APP");
    private static final byte[] APPLABEL_311 = toCBytes("SMBAppKey");

    private static final byte[] ENCCONTEXT_300 = toCBytes("ServerIn "); // there really is a space there
    private static final byte[] ENCLABEL_300 = toCBytes("SMB2AESCCM");