xref: /freebsd/contrib/libfido2/openbsd-compat/timingsafe_bcmp.c (revision 2e3507c25e42292b45a5482e116d278f5515d04d)
1 /*	$OpenBSD: timingsafe_bcmp.c,v 1.1 2010/09/24 13:33:00 matthew Exp $	*/
2 /*
3  * Copyright (c) 2010 Damien Miller.  All rights reserved.
4  *
5  * Permission to use, copy, modify, and distribute this software for any
6  * purpose with or without fee is hereby granted, provided that the above
7  * copyright notice and this permission notice appear in all copies.
8  *
9  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16  */
17 
18 /* OPENBSD ORIGINAL: lib/libc/string/timingsafe_bcmp.c */
19 
20 #include "openbsd-compat.h"
21 
22 #if !defined(HAVE_TIMINGSAFE_BCMP)
23 
24 int
25 timingsafe_bcmp(const void *b1, const void *b2, size_t n)
26 {
27 	const unsigned char *p1 = b1, *p2 = b2;
28 	int ret = 0;
29 
30 	for (; n > 0; n--)
31 		ret |= *p1++ ^ *p2++;
32 	return (ret != 0);
33 }
34 
35 #endif /* !defined(HAVE_TIMINGSAFE_BCMP) */
36