diff --git a/library/ssl_misc.h b/library/ssl_misc.h
index 7035c27..9cd1b35 100644
--- a/library/ssl_misc.h
+++ b/library/ssl_misc.h
@@ -1348,6 +1348,49 @@
 void mbedtls_ssl_flight_free( mbedtls_ssl_flight_item *flight );
 #endif /* MBEDTLS_SSL_PROTO_DTLS */
 
+#if defined(MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL)
+
+/*
+ * Helper functions around key exchange modes.
+ */
+static inline unsigned mbedtls_ssl_conf_tls13_kex_modes_check( mbedtls_ssl_context *ssl,
+                                                               int kex_mode_mask )
+{
+    return( ( ssl->conf->tls13_kex_modes & kex_mode_mask ) != 0 );
+}
+
+static inline int mbedtls_ssl_conf_tls13_pure_psk_enabled( mbedtls_ssl_context *ssl )
+{
+    return( mbedtls_ssl_conf_tls13_kex_modes_check( ssl,
+                   MBEDTLS_SSL_TLS13_KEY_EXCHANGE_MODE_PSK ) );
+}
+
+static inline int mbedtls_ssl_conf_tls13_psk_ephemeral_enabled( mbedtls_ssl_context *ssl )
+{
+    return( mbedtls_ssl_conf_tls13_kex_modes_check( ssl,
+                   MBEDTLS_SSL_TLS13_KEY_EXCHANGE_MODE_PSK_EPHEMERAL ) );
+}
+
+static inline int mbedtls_ssl_conf_tls13_pure_ephemeral_enabled( mbedtls_ssl_context *ssl )
+{
+    return( mbedtls_ssl_conf_tls13_kex_modes_check( ssl,
+                   MBEDTLS_SSL_TLS13_KEY_EXCHANGE_MODE_EPHEMERAL ) );
+}
+
+static inline int mbedtls_ssl_conf_tls13_some_ephemeral_enabled( mbedtls_ssl_context *ssl )
+{
+    return( mbedtls_ssl_conf_tls13_kex_modes_check( ssl,
+                   MBEDTLS_SSL_TLS13_KEY_EXCHANGE_MODE_EPHEMERAL_ALL ) );
+}
+
+static inline int mbedtls_ssl_conf_tls13_some_psk_enabled( mbedtls_ssl_context *ssl )
+{
+    return( mbedtls_ssl_conf_tls13_kex_modes_check( ssl,
+                   MBEDTLS_SSL_TLS13_KEY_EXCHANGE_MODE_PSK_ALL ) );
+}
+
+#endif /* MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL */
+
 /**
  * ssl utils functions for checking configuration.
  */