return "tlsv1.1";
case TLS1_2_VERSION:
return "tlsv1.2";
#if OPENSSL_VERSION_NUMBER >= 0x10101000L
#if (OPENSSL_VERSION_NUMBER >= 0x10100000L && !defined(LIBRESSL_VERSION_NUMBER)) || (LIBRESSL_VERSION_NUMBER >= 0x3040000fL)
case TLS1_3_VERSION:
return "tlsv1.3";
#endif