mirror of
https://github.com/isc-projects/bind9.git
synced 2026-02-21 08:50:32 -05:00
67 lines
1.7 KiB
C
67 lines
1.7 KiB
C
/*
|
|
* Copyright (C) 2013, 2015 Internet Systems Consortium, Inc. ("ISC")
|
|
*
|
|
* Permission to use, copy, modify, and/or distribute this software for any
|
|
* purpose with or without fee is hereby granted, provided that the above
|
|
* copyright notice and this permission notice appear in all copies.
|
|
*
|
|
* THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
|
|
* REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
|
|
* AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
|
|
* INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
|
|
* LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
|
|
* OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
|
|
* PERFORMANCE OF THIS SOFTWARE.
|
|
*/
|
|
|
|
/*! \file */
|
|
|
|
#include <config.h>
|
|
|
|
#include <isc/safe.h>
|
|
#include <isc/util.h>
|
|
|
|
#ifdef _MSC_VER
|
|
#pragma optimize("", off)
|
|
#endif
|
|
|
|
isc_boolean_t
|
|
isc_safe_memequal(const void *s1, const void *s2, size_t n) {
|
|
isc_uint8_t acc = 0;
|
|
|
|
if (n != 0U) {
|
|
const isc_uint8_t *p1 = s1, *p2 = s2;
|
|
|
|
do {
|
|
acc |= *p1++ ^ *p2++;
|
|
} while (--n != 0U);
|
|
}
|
|
return (ISC_TF(acc == 0));
|
|
}
|
|
|
|
|
|
int
|
|
isc_safe_memcompare(const void *b1, const void *b2, size_t len) {
|
|
const unsigned char *p1 = b1, *p2 = b2;
|
|
size_t i;
|
|
int res = 0, done = 0;
|
|
|
|
for (i = 0; i < len; i++) {
|
|
/* lt is -1 if p1[i] < p2[i]; else 0. */
|
|
int lt = (p1[i] - p2[i]) >> CHAR_BIT;
|
|
|
|
/* gt is -1 if p1[i] > p2[i]; else 0. */
|
|
int gt = (p2[i] - p1[i]) >> CHAR_BIT;
|
|
|
|
/* cmp is 1 if p1[i] > p2[i]; -1 if p1[i] < p2[i]; else 0. */
|
|
int cmp = lt - gt;
|
|
|
|
/* set res = cmp if !done. */
|
|
res |= cmp & ~done;
|
|
|
|
/* set done if p1[i] != p2[i]. */
|
|
done |= lt | gt;
|
|
}
|
|
|
|
return (res);
|
|
}
|