freebsd-nq/contrib/unbound/edns-subnet/edns-subnet.c
2018-05-12 14:15:39 +00:00

66 lines
2.3 KiB
C

/*
* edns-subnet/edns-subnet.c - Subnet option related constants
*
* Copyright (c) 2013, NLnet Labs. All rights reserved.
*
* This software is open source.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* 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.
*
* Neither the name of the NLNET LABS nor the names of its contributors may
* be used to endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 COPYRIGHT
* HOLDER 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.
*/
/**
* \file
* Subnet option related constants.
*/
#include "config.h"
#ifdef CLIENT_SUBNET /* keeps splint happy */
#include "edns-subnet/edns-subnet.h"
#include <string.h>
int
copy_clear(uint8_t* dst, size_t dstlen, uint8_t* src, size_t srclen, size_t n)
{
size_t intpart = n / 8; /* bytes */
size_t fracpart = n % 8; /* bits */
size_t written = intpart;
if (intpart > dstlen || intpart > srclen)
return 1;
if (fracpart && (intpart+1 > dstlen || intpart+1 > srclen))
return 1;
memcpy(dst, src, intpart);
if (fracpart) {
dst[intpart] = src[intpart] & ~(0xFF >> fracpart);
written++;
}
memset(dst + written, 0, dstlen - written);
return 0;
}
#endif /* CLIENT_SUBNET */