diff --git a/library/ssl_misc.h b/library/ssl_misc.h
index 46d85d9..fa336e4 100644
--- a/library/ssl_misc.h
+++ b/library/ssl_misc.h
@@ -1781,6 +1781,16 @@
 
 int mbedtls_ssl_reset_transcript_for_hrr( mbedtls_ssl_context *ssl );
 
+#if defined(MBEDTLS_ECDH_C)
+int mbedtls_ssl_tls13_generate_and_write_ecdh_key_exchange(
+                mbedtls_ssl_context *ssl,
+                uint16_t named_group,
+                unsigned char *buf,
+                unsigned char *end,
+                size_t *out_len );
+#endif /* MBEDTLS_ECDH_C */
+
+
 #endif /* MBEDTLS_SSL_PROTO_TLS1_3 */
 
 #if defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED)