cryb-to/lib/core/cryb_memset_s.c

62 lines
2.1 KiB
C

/*-
* Copyright (c) 2015 The University of Oslo
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote
* products derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#if HAVE_CONFIG_H
#include "config.h"
#endif
#include <errno.h>
#include <limits.h>
#include <stdint.h>
#include <string.h>
#include <cryb/coverage.h>
#include <cryb/memset_s.h>
/*
* Like memset(), but checks for overflow and guarantees that the buffer
* is overwritten even if the data will never be read.
*/
int
cryb_memset_s(void *d, size_t dsz, int ch, size_t n)
{
unsigned int i;
if (d == NULL)
return (EINVAL);
CRYB_DISABLE_COVERAGE
if (dsz > SIZE_MAX || n > SIZE_MAX)
return (ERANGE);
CRYB_RESTORE_COVERAGE
for (i = 0; i < n && i < dsz; ++i)
((volatile unsigned char *)d)[i] = (unsigned char)ch;
if (n > dsz)
return (EOVERFLOW);
return (0);
}