soa.c revision e7a4f58d55042cbc981a70b5071aaea46b9ebf7f
/*
* Copyright (C) 1999-2001 Internet Software Consortium.
*
* Permission to use, copy, modify, and 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 INTERNET SOFTWARE CONSORTIUM
* DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL
* INTERNET SOFTWARE CONSORTIUM 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.
*/
/* $Id: soa.c,v 1.1 2001/05/21 23:56:32 gson Exp $ */
#include <config.h>
#include <isc/util.h>
#include <dns/rdata.h>
#include <dns/soa.h>
static inline isc_uint32_t
decode_uint32(unsigned char *p) {
return ((p[0] << 24) +
(p[1] << 16) +
(p[2] << 8) +
(p[3] << 0));
}
static inline void
encode_uint32(isc_uint32_t val, unsigned char *p) {
p[0] = (isc_uint8_t)(val >> 24);
p[1] = (isc_uint8_t)(val >> 16);
p[2] = (isc_uint8_t)(val >> 8);
p[3] = (isc_uint8_t)(val >> 0);
}
static isc_uint32_t
soa_get(dns_rdata_t *rdata, int offset) {
INSIST(rdata->type == dns_rdatatype_soa);
/*
* Locate the field within the SOA RDATA based
* on its position relative to the end of the data.
*
* This is a bit of a kludge, but the alternative approach of
* using dns_rdata_tostruct() and dns_rdata_fromstruct() would
* involve a lot of unnecessary work (like building domain
* names and allocating temporary memory) when all we really
* want to do is to get 32 bits of fixed-sized data.
*/
INSIST(rdata->length >= 20);
INSIST(offset >= 0 && offset <= 16);
return (decode_uint32(rdata->data + rdata->length - 20 + offset));
}
isc_uint32_t
dns_soa_getserial(dns_rdata_t *rdata) {
return soa_get(rdata, 0);
}
isc_uint32_t
dns_soa_getrefresh(dns_rdata_t *rdata) {
return soa_get(rdata, 4);
}
isc_uint32_t
dns_soa_getretry(dns_rdata_t *rdata) {
return soa_get(rdata, 8);
}
isc_uint32_t
dns_soa_getexpire(dns_rdata_t *rdata) {
return soa_get(rdata, 12);
}
isc_uint32_t
dns_soa_getminimum(dns_rdata_t *rdata) {
return soa_get(rdata, 16);
}
static void
soa_set(dns_rdata_t *rdata, isc_uint32_t val, int offset) {
INSIST(rdata->type == dns_rdatatype_soa);
INSIST(rdata->length >= 20);
INSIST(offset >= 0 && offset <= 16);
encode_uint32(val, rdata->data + rdata->length - 20 + offset);
}
void
dns_soa_setserial(isc_uint32_t val, dns_rdata_t *rdata) {
return soa_set(rdata, val, 0);
}
void
dns_soa_setrefresh(isc_uint32_t val, dns_rdata_t *rdata) {
return soa_set(rdata, val, 4);
}
void
dns_soa_setretry(isc_uint32_t val, dns_rdata_t *rdata) {
return soa_set(rdata, val, 8);
}
void
dns_soa_setexpire(isc_uint32_t val, dns_rdata_t *rdata) {
return soa_set(rdata, val, 12);
}
void
dns_soa_setminimum(isc_uint32_t val, dns_rdata_t *rdata) {
return soa_set(rdata, val, 16);
}