diff --git a/library/cmac.c b/library/cmac.c
index 063a9d1..d32d1c7 100644
--- a/library/cmac.c
+++ b/library/cmac.c
@@ -74,7 +74,6 @@
                                const unsigned char *input,
 							   size_t blocksize )
 {
-
     const unsigned char R_128 = 0x87;
     const unsigned char R_64 = 0x1B;
     unsigned char R_n, mask;
@@ -91,7 +90,6 @@
         return( MBEDTLS_ERR_CMAC_BAD_INPUT );
     }
 
-
     for( i = starting_index; i >= 0; i-- )
     {
         output[i] = input[i] << 1 | overflow;
@@ -128,13 +126,12 @@
     block_size = ctx->cipher_ctx.cipher_info->block_size;
 
     L = mbedtls_calloc( block_size, sizeof( unsigned char ) );
-    if( L == NULL)
+    if( L == NULL )
     {
         ret = MBEDTLS_ERR_CMAC_ALLOC_FAILED;
         goto exit;
     }
     /* Calculate Ek(0) */
-    memset( L, 0, block_size );
     if( ( ret = mbedtls_cipher_update( &ctx->cipher_ctx,
                                        L, block_size, L, &olen ) ) != 0 )
     {
@@ -152,7 +149,7 @@
     exit:
         if( L != NULL )
             mbedtls_zeroize( L, sizeof( L ) );
-		free( L );
+		mbedtls_free( L );
         return( ret );
 }
 
@@ -308,8 +305,6 @@
         XOR_BLOCK( M_last, input + block_size * ( n - 1 ), ctx->K1 );
     }
 
-    memset( state, 0, block_size );
-
     for( j = 0; j < n - 1; j++ )
         UPDATE_CMAC( input + block_size * j );
 
@@ -318,8 +313,8 @@
     memcpy( tag, state, tag_len );
 
     exit:
-        free( state );
-        free( M_last );
+        mbedtls_free( state );
+        mbedtls_free( M_last );
         return( ret );
 }
 
@@ -340,7 +335,7 @@
 
     check_tag = mbedtls_calloc( ctx->cipher_ctx.cipher_info->block_size,
                                 sizeof( unsigned char ) );
-    if(check_tag == NULL)
+    if( check_tag == NULL )
     {
         ret = MBEDTLS_ERR_CMAC_ALLOC_FAILED;
         goto exit;
@@ -361,7 +356,7 @@
         goto exit;
 
     exit:
-	    free( check_tag );
+        mbedtls_free( check_tag );
         return( ret );
 }
 
@@ -727,14 +722,14 @@
 
         if( ( ret = mbedtls_cmac_verify( &ctx, messages, message_lengths[i], &expected_result[i * block_size], block_size ) != 0 ) )
         {
-                if( verbose != 0 )
-                    mbedtls_printf( "failed\n" );
-                goto exit;
+             if( verbose != 0 )
+                 mbedtls_printf( "failed\n" );
+             goto exit;
         }
         mbedtls_printf( "passed\n" );
     }
     exit:
-        free( tag );
+        mbedtls_free( tag );
         mbedtls_cmac_free( &ctx );
         return( ret );
 }