From 604e60d915e3894db546bad2f543366162cacac2 Mon Sep 17 00:00:00 2001
From: Nir Sonnenschein <nir.sonnenschein@arm.com>
Date: Mon, 30 Jul 2018 17:01:10 +0300
Subject: [PATCH] add default value for CTR DRBG key size

---
 include/mbedtls/config.h | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/include/mbedtls/config.h b/include/mbedtls/config.h
index 70820be56..a79dff83e 100644
--- a/include/mbedtls/config.h
+++ b/include/mbedtls/config.h
@@ -2018,7 +2018,7 @@
 /**
  * \def MBEDTLS_CTR_DRBG_C
  *
- * Enable the CTR_DRBG AES-256-based random generator.
+ * Enable the CTR_DRBG AES-256-based(default) or AES-128-based random generator.
  *
  * Module:  library/ctr_drbg.c
  * Caller:
@@ -2029,6 +2029,16 @@
  */
 #define MBEDTLS_CTR_DRBG_C
 
+/**
+ * configure key size for ctr DRBG , either 
+ * MBEDTLS_CTR_DRBG_KEYSIZE_256 (default)
+ * or 
+ * MBEDTLS_CTR_DRBG_KEYSIZE_128
+ * must be set.
+ */
+#if !defined(MBEDTLS_CTR_DRBG_KEY_SIZE_128) 
+#define MBEDTLS_CTR_DRBG_KEY_SIZE_256 1
+#endif
 /**
  * \def MBEDTLS_DEBUG_C
  *