SSL_EXT_TLS1_3_ONLY
SSL_EXT_TLS1_3_ONLY
SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_3_ONLY,
| SSL_EXT_TLS1_3_ONLY,
| SSL_EXT_TLS1_3_ONLY,
| SSL_EXT_TLS_IMPLEMENTATION_ONLY | SSL_EXT_TLS1_3_ONLY,
| SSL_EXT_TLS_IMPLEMENTATION_ONLY | SSL_EXT_TLS1_3_ONLY,
| SSL_EXT_TLS1_3_NEW_SESSION_TICKET | SSL_EXT_TLS1_3_ONLY,
| SSL_EXT_TLS1_3_ONLY,
| SSL_EXT_TLS_IMPLEMENTATION_ONLY | SSL_EXT_TLS1_3_ONLY,
|| (!is_tls13 && (extctx & SSL_EXT_TLS1_3_ONLY) != 0
|| (s->server && !is_tls13 && (extctx & SSL_EXT_TLS1_3_ONLY) != 0)
|| ((extctx & SSL_EXT_TLS1_3_ONLY) != 0