unleashed-firmware/applications/plugins/totp/services/hmac/memxor.c

/* memxor.c -- perform binary exclusive OR operation of two memory blocks.
   Copyright (C) 2005, 2006 Free Software Foundation, Inc.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2, or (at your option)
   any later version.

   This program 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 General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software Foundation,
   Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */

/* Written by Simon Josefsson.  The interface was inspired by memxor
   in Niels Möller's Nettle. */

/* #include <config.h> */

#include "memxor.h"

void* memxor(void* /*restrict*/ dest, const void* /*restrict*/ src, size_t n) {
    char const* s = (char const*)src;
    char* d = (char*)dest;

    for(; n > 0; n--) *d++ ^= *s++;

    return dest;
}