xref: /freebsd/crypto/openssh/openbsd-compat/timingsafe_bcmp.c (revision 0a36787e4c1fa0cf77dcf83be0867178476e372b)
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 "includes.h"
21 #ifndef HAVE_TIMINGSAFE_BCMP
22 
23 int
24 timingsafe_bcmp(const void *b1, const void *b2, size_t n)
25 {
26 	const unsigned char *p1 = b1, *p2 = b2;
27 	int ret = 0;
28 
29 	for (; n > 0; n--)
30 		ret |= *p1++ ^ *p2++;
31 	return (ret != 0);
32 }
33 
34 #endif /* TIMINGSAFE_BCMP */
35