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/**
* Copyright (c) 2021 Paul-Louis Ageneau
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "const_time.h"
int const_time_memcmp(const void *a, const void *b, size_t len) {
const unsigned char *ca = a;
const unsigned char *cb = b;
unsigned char x = 0;
for (size_t i = 0; i < len; i++)
x |= ca[i] ^ cb[i];
return x;
}
int const_time_strcmp(const void *a, const void *b) {
const unsigned char *ca = a;
const unsigned char *cb = b;
unsigned char x = 0;
size_t i = 0;
for(;;) {
x |= ca[i] ^ cb[i];
if (!ca[i] || !cb[i])
break;
++i;
}
return x;
}