tls13_only: add tls13_only test component

Signed-off-by: Jerry Yu <jerry.h.yu@arm.com>
diff --git a/tests/configs/tls13-only.h b/tests/configs/tls13-only.h
new file mode 100644
index 0000000..fa043b7
--- /dev/null
+++ b/tests/configs/tls13-only.h
@@ -0,0 +1,58 @@
+/* MBEDTLS_USER_CONFIG_FILE for testing.
+ * Only used for a few test configurations.
+ *
+ * Typical usage (note multiple levels of quoting):
+ *     make CFLAGS="'-DMBEDTLS_USER_CONFIG_FILE=\"../tests/configs/tls13-only.h\"'"
+ */
+
+/*
+ *  Copyright The Mbed TLS Contributors
+ *  SPDX-License-Identifier: Apache-2.0
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License"); you may
+ *  not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *  http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
+#undef MBEDTLS_SSL_ENCRYPT_THEN_MAC
+#endif
+
+#if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET)
+#undef MBEDTLS_SSL_EXTENDED_MASTER_SECRET
+#endif
+
+#if defined(MBEDTLS_SSL_PROTO_TLS1_2)
+#undef MBEDTLS_SSL_PROTO_TLS1_2
+#endif
+
+#if !defined(MBEDTLS_SSL_PROTO_TLS1_3)
+#define MBEDTLS_SSL_PROTO_TLS1_3
+#endif
+
+#if !defined(MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE)
+#define MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
+#endif
+
+#if defined(MBEDTLS_SSL_PROTO_DTLS)
+#undef MBEDTLS_SSL_PROTO_DTLS
+#endif
+
+#if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY)
+#undef MBEDTLS_SSL_DTLS_ANTI_REPLAY
+#endif
+
+#if defined(MBEDTLS_SSL_DTLS_HELLO_VERIFY)
+#undef MBEDTLS_SSL_DTLS_HELLO_VERIFY
+#endif
+
+#if defined(MBEDTLS_SSL_DTLS_CLIENT_PORT_REUSE)
+#undef MBEDTLS_SSL_DTLS_CLIENT_PORT_REUSE
+#endif