1/* Copyright (c) (2014,2015,2019,2021) Apple Inc. All rights reserved.
2 *
3 * corecrypto is licensed under Apple Inc.’s Internal Use License Agreement (which
4 * is contained in the License.txt file distributed with corecrypto) and only to
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11 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
12 *
13 * This file contains Original Code and/or Modifications of Original Code
14 * as defined in and that are subject to the Apple Public Source License
15 * Version 2.0 (the 'License'). You may not use this file except in
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34 */
35
36#include "cc_internal.h"
37#include <corecrypto/cc_priv.h>
38
39int
40cc_cmp_safe(size_t num, const void * ptr1, const void * ptr2)
41{
42 CC_ENSURE_DIT_ENABLED
43
44 size_t i;
45 const uint8_t *s = (const uint8_t *)ptr1;
46 const uint8_t *t = (const uint8_t *)ptr2;
47 uint8_t flag = ((num <= 0)?1:0); // If 0 return an error
48 for (i = 0; i < num; i++) {
49 flag |= (s[i] ^ t[i]);
50 }
51 CC_HEAVISIDE_STEP(flag, flag); // flag=(flag==0)?0:1;
52 return flag; // 0 iff all bytes were equal, 1 if there is any difference
53}
54