diff --git a/library/des.c b/library/des.c
index 863a80c..ca9e071 100644
--- a/library/des.c
+++ b/library/des.c
@@ -34,7 +34,7 @@
 #if defined(MBEDTLS_DES_C)
 
 #include "mbedtls/des.h"
-#include "mbedtls/utils.h"
+#include "mbedtls/platform_util.h"
 
 #include <string.h>
 
@@ -312,7 +312,7 @@
     if( ctx == NULL )
         return;
 
-    mbedtls_zeroize( ctx, sizeof( mbedtls_des_context ) );
+    mbedtls_platform_zeroize( ctx, sizeof( mbedtls_des_context ) );
 }
 
 void mbedtls_des3_init( mbedtls_des3_context *ctx )
@@ -325,7 +325,7 @@
     if( ctx == NULL )
         return;
 
-    mbedtls_zeroize( ctx, sizeof( mbedtls_des3_context ) );
+    mbedtls_platform_zeroize( ctx, sizeof( mbedtls_des3_context ) );
 }
 
 static const unsigned char odd_parity_table[128] = { 1,  2,  4,  7,  8,
@@ -549,7 +549,7 @@
     uint32_t sk[96];
 
     des3_set2key( ctx->sk, sk, key );
-    mbedtls_zeroize( sk,  sizeof( sk ) );
+    mbedtls_platform_zeroize( sk,  sizeof( sk ) );
 
     return( 0 );
 }
@@ -563,7 +563,7 @@
     uint32_t sk[96];
 
     des3_set2key( sk, ctx->sk, key );
-    mbedtls_zeroize( sk,  sizeof( sk ) );
+    mbedtls_platform_zeroize( sk,  sizeof( sk ) );
 
     return( 0 );
 }
@@ -600,7 +600,7 @@
     uint32_t sk[96];
 
     des3_set3key( ctx->sk, sk, key );
-    mbedtls_zeroize( sk,  sizeof( sk ) );
+    mbedtls_platform_zeroize( sk,  sizeof( sk ) );
 
     return( 0 );
 }
@@ -614,7 +614,7 @@
     uint32_t sk[96];
 
     des3_set3key( sk, ctx->sk, key );
-    mbedtls_zeroize( sk,  sizeof( sk ) );
+    mbedtls_platform_zeroize( sk,  sizeof( sk ) );
 
     return( 0 );
 }