/* $NetBSD: soa.c,v 1.1.4.2 2024/02/29 11:38:42 martin Exp $ */ /* * Copyright (C) Internet Systems Consortium, Inc. ("ISC") * * SPDX-License-Identifier: MPL-2.0 * * This Source Code Form is subject to the terms of the Mozilla Public * License, v. 2.0. If a copy of the MPL was not distributed with this * file, you can obtain one at https://mozilla.org/MPL/2.0/. * * See the COPYRIGHT file distributed with this work for additional * information regarding copyright ownership. */ /*! \file */ #include #include #include #include #include #include #include static uint32_t decode_uint32(unsigned char *p) { return (((uint32_t)p[0] << 24) + ((uint32_t)p[1] << 16) + ((uint32_t)p[2] << 8) + ((uint32_t)p[3] << 0)); } static void encode_uint32(uint32_t val, unsigned char *p) { p[0] = (uint8_t)(val >> 24); p[1] = (uint8_t)(val >> 16); p[2] = (uint8_t)(val >> 8); p[3] = (uint8_t)(val >> 0); } static 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_result_t dns_soa_buildrdata(const dns_name_t *origin, const dns_name_t *contact, dns_rdataclass_t rdclass, uint32_t serial, uint32_t refresh, uint32_t retry, uint32_t expire, uint32_t minimum, unsigned char *buffer, dns_rdata_t *rdata) { dns_rdata_soa_t soa; isc_buffer_t rdatabuf; REQUIRE(origin != NULL); REQUIRE(contact != NULL); memset(buffer, 0, DNS_SOA_BUFFERSIZE); isc_buffer_init(&rdatabuf, buffer, DNS_SOA_BUFFERSIZE); soa.common.rdtype = dns_rdatatype_soa; soa.common.rdclass = rdclass; soa.mctx = NULL; soa.serial = serial; soa.refresh = refresh; soa.retry = retry; soa.expire = expire; soa.minimum = minimum; dns_name_init(&soa.origin, NULL); dns_name_clone(origin, &soa.origin); dns_name_init(&soa.contact, NULL); dns_name_clone(contact, &soa.contact); return (dns_rdata_fromstruct(rdata, rdclass, dns_rdatatype_soa, &soa, &rdatabuf)); } uint32_t dns_soa_getserial(dns_rdata_t *rdata) { return (soa_get(rdata, 0)); } uint32_t dns_soa_getrefresh(dns_rdata_t *rdata) { return (soa_get(rdata, 4)); } uint32_t dns_soa_getretry(dns_rdata_t *rdata) { return (soa_get(rdata, 8)); } uint32_t dns_soa_getexpire(dns_rdata_t *rdata) { return (soa_get(rdata, 12)); } uint32_t dns_soa_getminimum(dns_rdata_t *rdata) { return (soa_get(rdata, 16)); } static void soa_set(dns_rdata_t *rdata, 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(uint32_t val, dns_rdata_t *rdata) { soa_set(rdata, val, 0); } void dns_soa_setrefresh(uint32_t val, dns_rdata_t *rdata) { soa_set(rdata, val, 4); } void dns_soa_setretry(uint32_t val, dns_rdata_t *rdata) { soa_set(rdata, val, 8); } void dns_soa_setexpire(uint32_t val, dns_rdata_t *rdata) { soa_set(rdata, val, 12); } void dns_soa_setminimum(uint32_t val, dns_rdata_t *rdata) { soa_set(rdata, val, 16); }