1*854023f0SXin LI /* $OpenBSD: timingsafe_bcmp.c,v 1.3 2015/08/31 02:53:57 guenther Exp $ */
2*854023f0SXin LI /*
3*854023f0SXin LI * Copyright (c) 2010 Damien Miller. All rights reserved.
4*854023f0SXin LI *
5*854023f0SXin LI * Permission to use, copy, modify, and distribute this software for any
6*854023f0SXin LI * purpose with or without fee is hereby granted, provided that the above
7*854023f0SXin LI * copyright notice and this permission notice appear in all copies.
8*854023f0SXin LI *
9*854023f0SXin LI * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10*854023f0SXin LI * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11*854023f0SXin LI * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12*854023f0SXin LI * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13*854023f0SXin LI * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14*854023f0SXin LI * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15*854023f0SXin LI * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16*854023f0SXin LI */
17*854023f0SXin LI
18*854023f0SXin LI #include <string.h>
19*854023f0SXin LI
20*854023f0SXin LI int __timingsafe_bcmp(const void *, const void *, size_t);
21*854023f0SXin LI
22*854023f0SXin LI int
__timingsafe_bcmp(const void * b1,const void * b2,size_t n)23*854023f0SXin LI __timingsafe_bcmp(const void *b1, const void *b2, size_t n)
24*854023f0SXin LI {
25*854023f0SXin LI const unsigned char *p1 = b1, *p2 = b2;
26*854023f0SXin LI int ret = 0;
27*854023f0SXin LI
28*854023f0SXin LI for (; n > 0; n--)
29*854023f0SXin LI ret |= *p1++ ^ *p2++;
30*854023f0SXin LI return (ret != 0);
31*854023f0SXin LI }
32*854023f0SXin LI
33*854023f0SXin LI __weak_reference(__timingsafe_bcmp, timingsafe_bcmp);
34