diff --git a/include/mbedtls/mbedtls_config.h b/include/mbedtls/mbedtls_config.h
index 2d32f67..ad96961 100644
--- a/include/mbedtls/mbedtls_config.h
+++ b/include/mbedtls/mbedtls_config.h
@@ -225,6 +225,7 @@
  * Uncomment a macro to enable alternate implementation of specific base
  * platform function
  */
+//#define MBEDTLS_PLATFORM_SETBUF_ALT
 //#define MBEDTLS_PLATFORM_EXIT_ALT
 //#define MBEDTLS_PLATFORM_TIME_ALT
 //#define MBEDTLS_PLATFORM_FPRINTF_ALT
@@ -3288,6 +3289,7 @@
 //#define MBEDTLS_PLATFORM_STD_MEM_HDR   <stdlib.h> /**< Header to include if MBEDTLS_PLATFORM_NO_STD_FUNCTIONS is defined. Don't define if no header is needed. */
 //#define MBEDTLS_PLATFORM_STD_CALLOC        calloc /**< Default allocator to use, can be undefined */
 //#define MBEDTLS_PLATFORM_STD_FREE            free /**< Default free to use, can be undefined */
+//#define MBEDTLS_PLATFORM_STD_SETBUF      setbuf /**< Default setbuf to use, can be undefined */
 //#define MBEDTLS_PLATFORM_STD_EXIT            exit /**< Default exit to use, can be undefined */
 //#define MBEDTLS_PLATFORM_STD_TIME            time /**< Default time to use, can be undefined. MBEDTLS_HAVE_TIME must be enabled */
 //#define MBEDTLS_PLATFORM_STD_FPRINTF      fprintf /**< Default fprintf to use, can be undefined */
@@ -3305,6 +3307,7 @@
 //#define MBEDTLS_PLATFORM_CALLOC_MACRO        calloc /**< Default allocator macro to use, can be undefined */
 //#define MBEDTLS_PLATFORM_FREE_MACRO            free /**< Default free macro to use, can be undefined */
 //#define MBEDTLS_PLATFORM_EXIT_MACRO            exit /**< Default exit macro to use, can be undefined */
+//#define MBEDTLS_PLATFORM_SETBUF_MACRO      setbuf /**< Default setbuf macro to use, can be undefined */
 //#define MBEDTLS_PLATFORM_TIME_MACRO            time /**< Default time macro to use, can be undefined. MBEDTLS_HAVE_TIME must be enabled */
 //#define MBEDTLS_PLATFORM_TIME_TYPE_MACRO       time_t /**< Default time macro to use, can be undefined. MBEDTLS_HAVE_TIME must be enabled */
 //#define MBEDTLS_PLATFORM_FPRINTF_MACRO      fprintf /**< Default fprintf macro to use, can be undefined */