nxt.c revision 40f53fa8d9c6a4fc38c0014495e7a42b08f52481
/*
* Copyright (C) 1999, 2000 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: nxt.c,v 1.20 2000/08/01 01:22:36 tale Exp $ */
#include <config.h>
#include <isc/string.h>
#include <isc/util.h>
#include <dns/db.h>
#include <dns/nxt.h>
#include <dns/rdata.h>
#include <dns/rdatalist.h>
#include <dns/rdataset.h>
#include <dns/rdatasetiter.h>
#include <dns/result.h>
#define check_result(op, msg) \
do { result = (op); \
if (result != ISC_R_SUCCESS) { \
fprintf(stderr, "%s: %s\n", msg, \
isc_result_totext(result)); \
goto failure; \
} \
} while (0)
static void
set_bit(unsigned char *array, unsigned int index, unsigned int bit) {
unsigned int shift, mask;
shift = 7 - (index % 8);
mask = 1 << shift;
if (bit != 0)
array[index / 8] |= mask;
else
array[index / 8] &= (~mask & 0xFF);
}
static unsigned int
bit_isset(unsigned char *array, unsigned int index) {
unsigned int byte, shift, mask;
byte = array[index / 8];
shift = 7 - (index % 8);
mask = 1 << shift;
return ((byte & mask) != 0);
}
isc_result_t
dns_buildnxtrdata(dns_db_t *db, dns_dbversion_t *version,
dns_dbnode_t *node, dns_name_t *target,
unsigned char *buffer, dns_rdata_t *rdata)
{
isc_result_t result;
dns_rdataset_t rdataset;
isc_region_t r;
int i;
unsigned char *nxt_bits;
unsigned int max_type;
dns_rdatasetiter_t *rdsiter;
memset(buffer, 0, DNS_NXT_BUFFERSIZE);
dns_name_toregion(target, &r);
memcpy(buffer, r.base, r.length);
r.base = buffer;
nxt_bits = r.base + r.length;
set_bit(nxt_bits, dns_rdatatype_nxt, 1);
max_type = dns_rdatatype_nxt;
dns_rdataset_init(&rdataset);
rdsiter = NULL;
result = dns_db_allrdatasets(db, node, version, 0, &rdsiter);
if (result != ISC_R_SUCCESS)
return (result);
for (result = dns_rdatasetiter_first(rdsiter);
result == ISC_R_SUCCESS;
result = dns_rdatasetiter_next(rdsiter))
{
dns_rdatasetiter_current(rdsiter, &rdataset);
if (rdataset.type > 127)
/* XXX "rdataset type too large" */
return (ISC_R_RANGE);
if (rdataset.type != dns_rdatatype_nxt) {
if (rdataset.type > max_type)
max_type = rdataset.type;
set_bit(nxt_bits, rdataset.type, 1);
}
dns_rdataset_disassociate(&rdataset);
}
/*
* At zone cuts, deny the existence of glue in the parent zone.
*/
if (bit_isset(nxt_bits, dns_rdatatype_ns) &&
! bit_isset(nxt_bits, dns_rdatatype_soa)) {
for (i = 0; i < 128; i++) {
if (bit_isset(nxt_bits, i) &&
! dns_rdatatype_iszonecutauth((dns_rdatatype_t)i))
set_bit(nxt_bits, i, 0);
}
}
dns_rdatasetiter_destroy(&rdsiter);
if (result != ISC_R_NOMORE)
return (result);
r.length += ((max_type + 7) / 8);
INSIST(r.length <= DNS_NXT_BUFFERSIZE);
dns_rdata_fromregion(rdata,
dns_db_class(db),
dns_rdatatype_nxt,
&r);
return (ISC_R_SUCCESS);
}
isc_result_t
dns_buildnxt(dns_db_t *db, dns_dbversion_t *version, dns_dbnode_t *node,
dns_name_t *target, dns_ttl_t ttl)
{
isc_result_t result;
dns_rdata_t rdata;
unsigned char data[DNS_NXT_BUFFERSIZE];
dns_rdatalist_t rdatalist;
dns_rdataset_t rdataset;
dns_rdataset_init(&rdataset);
result = dns_buildnxtrdata(db, version, node,
target, data, &rdata);
check_result(result, "dns_buildnxtrdata");
rdatalist.rdclass = dns_rdataclass_in;
rdatalist.type = dns_rdatatype_nxt;
rdatalist.covers = 0;
rdatalist.ttl = ttl;
ISC_LIST_INIT(rdatalist.rdata);
ISC_LIST_APPEND(rdatalist.rdata, &rdata, link);
result = dns_rdatalist_tordataset(&rdatalist, &rdataset);
check_result(result, "dns_rdatalist_tordataset");
result = dns_db_addrdataset(db, node, version, 0, &rdataset,
0, NULL);
if (result == DNS_R_UNCHANGED)
result = ISC_R_SUCCESS;
check_result(result, "dns_db_addrdataset");
failure:
if (dns_rdataset_isassociated(&rdataset))
dns_rdataset_disassociate(&rdataset);
return (result);
}
isc_boolean_t
dns_nxt_typepresent(dns_rdata_t *nxt, dns_rdatatype_t type) {
dns_name_t name;
isc_region_t r, r2;
unsigned char *nxt_bits;
int nxt_bits_length;
REQUIRE(nxt != NULL);
REQUIRE(nxt->type == dns_rdatatype_nxt);
REQUIRE(type < 128);
dns_rdata_toregion(nxt, &r);
dns_name_init(&name, NULL);
dns_name_fromregion(&name, &r);
dns_name_toregion(&name, &r2);
nxt_bits = ((unsigned char *)r.base) + r2.length;
nxt_bits_length = r.length - r2.length;
if (type >= nxt_bits_length * 8)
return (ISC_FALSE);
else
return (ISC_TF(bit_isset(nxt_bits, type)));
}