diff options
Diffstat (limited to 'lib/dns/rdataset.c')
-rw-r--r-- | lib/dns/rdataset.c | 749 |
1 files changed, 749 insertions, 0 deletions
diff --git a/lib/dns/rdataset.c b/lib/dns/rdataset.c new file mode 100644 index 0000000..4d48203 --- /dev/null +++ b/lib/dns/rdataset.c @@ -0,0 +1,749 @@ +/* + * 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 <inttypes.h> +#include <stdbool.h> +#include <stdlib.h> + +#include <isc/buffer.h> +#include <isc/mem.h> +#include <isc/random.h> +#include <isc/serial.h> +#include <isc/util.h> + +#include <dns/compress.h> +#include <dns/fixedname.h> +#include <dns/name.h> +#include <dns/ncache.h> +#include <dns/rdata.h> +#include <dns/rdataset.h> + +static const char *trustnames[] = { + "none", "pending-additional", + "pending-answer", "additional", + "glue", "answer", + "authauthority", "authanswer", + "secure", "local" /* aka ultimate */ +}; + +const char * +dns_trust_totext(dns_trust_t trust) { + if (trust >= sizeof(trustnames) / sizeof(*trustnames)) { + return ("bad"); + } + return (trustnames[trust]); +} + +void +dns_rdataset_init(dns_rdataset_t *rdataset) { + /* + * Make 'rdataset' a valid, disassociated rdataset. + */ + + REQUIRE(rdataset != NULL); + + rdataset->magic = DNS_RDATASET_MAGIC; + rdataset->methods = NULL; + ISC_LINK_INIT(rdataset, link); + rdataset->rdclass = 0; + rdataset->type = 0; + rdataset->ttl = 0; + rdataset->trust = 0; + rdataset->covers = 0; + rdataset->attributes = 0; + rdataset->count = DNS_RDATASET_COUNT_UNDEFINED; + rdataset->private1 = NULL; + rdataset->private2 = NULL; + rdataset->private3 = NULL; + rdataset->privateuint4 = 0; + rdataset->private5 = NULL; + rdataset->private6 = NULL; + rdataset->private7 = NULL; + rdataset->resign = 0; +} + +void +dns_rdataset_invalidate(dns_rdataset_t *rdataset) { + /* + * Invalidate 'rdataset'. + */ + + REQUIRE(DNS_RDATASET_VALID(rdataset)); + REQUIRE(rdataset->methods == NULL); + + rdataset->magic = 0; + ISC_LINK_INIT(rdataset, link); + rdataset->rdclass = 0; + rdataset->type = 0; + rdataset->ttl = 0; + rdataset->trust = 0; + rdataset->covers = 0; + rdataset->attributes = 0; + rdataset->count = DNS_RDATASET_COUNT_UNDEFINED; + rdataset->private1 = NULL; + rdataset->private2 = NULL; + rdataset->private3 = NULL; + rdataset->privateuint4 = 0; + rdataset->private5 = NULL; +} + +void +dns_rdataset_disassociate(dns_rdataset_t *rdataset) { + /* + * Disassociate 'rdataset' from its rdata, allowing it to be reused. + */ + + REQUIRE(DNS_RDATASET_VALID(rdataset)); + REQUIRE(rdataset->methods != NULL); + + (rdataset->methods->disassociate)(rdataset); + rdataset->methods = NULL; + ISC_LINK_INIT(rdataset, link); + rdataset->rdclass = 0; + rdataset->type = 0; + rdataset->ttl = 0; + rdataset->trust = 0; + rdataset->covers = 0; + rdataset->attributes = 0; + rdataset->count = DNS_RDATASET_COUNT_UNDEFINED; + rdataset->private1 = NULL; + rdataset->private2 = NULL; + rdataset->private3 = NULL; + rdataset->privateuint4 = 0; + rdataset->private5 = NULL; + rdataset->private6 = NULL; +} + +bool +dns_rdataset_isassociated(dns_rdataset_t *rdataset) { + /* + * Is 'rdataset' associated? + */ + + REQUIRE(DNS_RDATASET_VALID(rdataset)); + + if (rdataset->methods != NULL) { + return (true); + } + + return (false); +} + +static void +question_disassociate(dns_rdataset_t *rdataset) { + UNUSED(rdataset); +} + +static isc_result_t +question_cursor(dns_rdataset_t *rdataset) { + UNUSED(rdataset); + + return (ISC_R_NOMORE); +} + +static void +question_current(dns_rdataset_t *rdataset, dns_rdata_t *rdata) { + /* + * This routine should never be called. + */ + UNUSED(rdataset); + UNUSED(rdata); + + REQUIRE(0); +} + +static void +question_clone(dns_rdataset_t *source, dns_rdataset_t *target) { + *target = *source; +} + +static unsigned int +question_count(dns_rdataset_t *rdataset) { + /* + * This routine should never be called. + */ + UNUSED(rdataset); + REQUIRE(0); + + return (0); +} + +static dns_rdatasetmethods_t question_methods = { + question_disassociate, + question_cursor, + question_cursor, + question_current, + question_clone, + question_count, + NULL, /* addnoqname */ + NULL, /* getnoqname */ + NULL, /* addclosest */ + NULL, /* getclosest */ + NULL, /* settrust */ + NULL, /* expire */ + NULL, /* clearprefetch */ + NULL, /* setownercase */ + NULL, /* getownercase */ + NULL /* addglue */ +}; + +void +dns_rdataset_makequestion(dns_rdataset_t *rdataset, dns_rdataclass_t rdclass, + dns_rdatatype_t type) { + /* + * Make 'rdataset' a valid, associated, question rdataset, with a + * question class of 'rdclass' and type 'type'. + */ + + REQUIRE(DNS_RDATASET_VALID(rdataset)); + REQUIRE(rdataset->methods == NULL); + + rdataset->methods = &question_methods; + rdataset->rdclass = rdclass; + rdataset->type = type; + rdataset->attributes |= DNS_RDATASETATTR_QUESTION; +} + +unsigned int +dns_rdataset_count(dns_rdataset_t *rdataset) { + /* + * Return the number of records in 'rdataset'. + */ + + REQUIRE(DNS_RDATASET_VALID(rdataset)); + REQUIRE(rdataset->methods != NULL); + + return ((rdataset->methods->count)(rdataset)); +} + +void +dns_rdataset_clone(dns_rdataset_t *source, dns_rdataset_t *target) { + /* + * Make 'target' refer to the same rdataset as 'source'. + */ + + REQUIRE(DNS_RDATASET_VALID(source)); + REQUIRE(source->methods != NULL); + REQUIRE(DNS_RDATASET_VALID(target)); + REQUIRE(target->methods == NULL); + + (source->methods->clone)(source, target); +} + +isc_result_t +dns_rdataset_first(dns_rdataset_t *rdataset) { + /* + * Move the rdata cursor to the first rdata in the rdataset (if any). + */ + + REQUIRE(DNS_RDATASET_VALID(rdataset)); + REQUIRE(rdataset->methods != NULL); + + return ((rdataset->methods->first)(rdataset)); +} + +isc_result_t +dns_rdataset_next(dns_rdataset_t *rdataset) { + /* + * Move the rdata cursor to the next rdata in the rdataset (if any). + */ + + REQUIRE(DNS_RDATASET_VALID(rdataset)); + REQUIRE(rdataset->methods != NULL); + + return ((rdataset->methods->next)(rdataset)); +} + +void +dns_rdataset_current(dns_rdataset_t *rdataset, dns_rdata_t *rdata) { + /* + * Make 'rdata' refer to the current rdata. + */ + + REQUIRE(DNS_RDATASET_VALID(rdataset)); + REQUIRE(rdataset->methods != NULL); + + (rdataset->methods->current)(rdataset, rdata); +} + +#define MAX_SHUFFLE 32 +#define WANT_FIXED(r) (((r)->attributes & DNS_RDATASETATTR_FIXEDORDER) != 0) +#define WANT_RANDOM(r) (((r)->attributes & DNS_RDATASETATTR_RANDOMIZE) != 0) +#define WANT_CYCLIC(r) (((r)->attributes & DNS_RDATASETATTR_CYCLIC) != 0) + +struct towire_sort { + int key; + dns_rdata_t *rdata; +}; + +static int +towire_compare(const void *av, const void *bv) { + const struct towire_sort *a = (const struct towire_sort *)av; + const struct towire_sort *b = (const struct towire_sort *)bv; + return (a->key - b->key); +} + +static void +swap_rdata(dns_rdata_t *in, unsigned int a, unsigned int b) { + dns_rdata_t rdata = in[a]; + in[a] = in[b]; + in[b] = rdata; +} + +static isc_result_t +towiresorted(dns_rdataset_t *rdataset, const dns_name_t *owner_name, + dns_compress_t *cctx, isc_buffer_t *target, + dns_rdatasetorderfunc_t order, const void *order_arg, bool partial, + unsigned int options, unsigned int *countp, void **state) { + isc_region_t r; + isc_result_t result; + unsigned int i, count = 0, added; + isc_buffer_t savedbuffer, rdlen, rrbuffer; + unsigned int headlen; + bool question = false; + bool shuffle = false, sort = false; + bool want_random, want_cyclic; + dns_rdata_t in_fixed[MAX_SHUFFLE]; + dns_rdata_t *in = in_fixed; + struct towire_sort out_fixed[MAX_SHUFFLE]; + struct towire_sort *out = out_fixed; + dns_fixedname_t fixed; + dns_name_t *name; + uint16_t offset; + + UNUSED(state); + + /* + * Convert 'rdataset' to wire format, compressing names as specified + * in cctx, and storing the result in 'target'. + */ + + REQUIRE(DNS_RDATASET_VALID(rdataset)); + REQUIRE(rdataset->methods != NULL); + REQUIRE(countp != NULL); + REQUIRE(cctx != NULL && cctx->mctx != NULL); + + want_random = WANT_RANDOM(rdataset); + want_cyclic = WANT_CYCLIC(rdataset); + + if ((rdataset->attributes & DNS_RDATASETATTR_QUESTION) != 0) { + question = true; + count = 1; + result = dns_rdataset_first(rdataset); + INSIST(result == ISC_R_NOMORE); + } else if ((rdataset->attributes & DNS_RDATASETATTR_NEGATIVE) != 0) { + /* + * This is a negative caching rdataset. + */ + unsigned int ncache_opts = 0; + if ((options & DNS_RDATASETTOWIRE_OMITDNSSEC) != 0) { + ncache_opts |= DNS_NCACHETOWIRE_OMITDNSSEC; + } + return (dns_ncache_towire(rdataset, cctx, target, ncache_opts, + countp)); + } else { + count = (rdataset->methods->count)(rdataset); + result = dns_rdataset_first(rdataset); + if (result == ISC_R_NOMORE) { + return (ISC_R_SUCCESS); + } + if (result != ISC_R_SUCCESS) { + return (result); + } + } + + /* + * Do we want to sort and/or shuffle this answer? + */ + if (!question && count > 1 && rdataset->type != dns_rdatatype_rrsig) { + if (order != NULL) { + sort = true; + } + if (want_random || want_cyclic) { + shuffle = true; + } + } + + if ((shuffle || sort)) { + if (count > MAX_SHUFFLE) { + in = isc_mem_get(cctx->mctx, count * sizeof(*in)); + out = isc_mem_get(cctx->mctx, count * sizeof(*out)); + if (in == NULL || out == NULL) { + shuffle = sort = false; + } + } + } + + if ((shuffle || sort)) { + uint32_t seed = 0; + unsigned int j = 0; + + /* + * First we get handles to all of the rdata. + */ + i = 0; + do { + INSIST(i < count); + dns_rdata_init(&in[i]); + dns_rdataset_current(rdataset, &in[i]); + i++; + result = dns_rdataset_next(rdataset); + } while (result == ISC_R_SUCCESS); + if (result != ISC_R_NOMORE) { + goto cleanup; + } + INSIST(i == count); + + if (want_random) { + seed = isc_random32(); + } + + if (want_cyclic && + (rdataset->count != DNS_RDATASET_COUNT_UNDEFINED)) + { + j = rdataset->count % count; + } + + for (i = 0; i < count; i++) { + if (want_random) { + swap_rdata(in, j, j + seed % (count - j)); + } + + out[i].key = (sort) ? (*order)(&in[j], order_arg) : 0; + out[i].rdata = &in[j]; + if (++j == count) { + j = 0; + } + } + /* + * Sortlist order. + */ + if (sort) { + qsort(out, count, sizeof(out[0]), towire_compare); + } + } + + savedbuffer = *target; + i = 0; + added = 0; + + name = dns_fixedname_initname(&fixed); + dns_name_copy(owner_name, name); + dns_rdataset_getownercase(rdataset, name); + offset = 0xffff; + + name->attributes |= owner_name->attributes & DNS_NAMEATTR_NOCOMPRESS; + + do { + /* + * Copy out the name, type, class, ttl. + */ + + rrbuffer = *target; + dns_compress_setmethods(cctx, DNS_COMPRESS_GLOBAL14); + result = dns_name_towire2(name, cctx, target, &offset); + if (result != ISC_R_SUCCESS) { + goto rollback; + } + headlen = sizeof(dns_rdataclass_t) + sizeof(dns_rdatatype_t); + if (!question) { + headlen += sizeof(dns_ttl_t) + 2; + } /* XXX 2 for rdata len + */ + isc_buffer_availableregion(target, &r); + if (r.length < headlen) { + result = ISC_R_NOSPACE; + goto rollback; + } + isc_buffer_putuint16(target, rdataset->type); + isc_buffer_putuint16(target, rdataset->rdclass); + if (!question) { + dns_rdata_t rdata = DNS_RDATA_INIT; + + isc_buffer_putuint32(target, rdataset->ttl); + + /* + * Save space for rdlen. + */ + rdlen = *target; + isc_buffer_add(target, 2); + + /* + * Copy out the rdata + */ + if (shuffle || sort) { + rdata = *(out[i].rdata); + } else { + dns_rdata_reset(&rdata); + dns_rdataset_current(rdataset, &rdata); + } + result = dns_rdata_towire(&rdata, cctx, target); + if (result != ISC_R_SUCCESS) { + goto rollback; + } + INSIST((target->used >= rdlen.used + 2) && + (target->used - rdlen.used - 2 < 65536)); + isc_buffer_putuint16( + &rdlen, + (uint16_t)(target->used - rdlen.used - 2)); + added++; + } + + if (shuffle || sort) { + i++; + if (i == count) { + result = ISC_R_NOMORE; + } else { + result = ISC_R_SUCCESS; + } + } else { + result = dns_rdataset_next(rdataset); + } + } while (result == ISC_R_SUCCESS); + + if (result != ISC_R_NOMORE) { + goto rollback; + } + + *countp += count; + + result = ISC_R_SUCCESS; + goto cleanup; + +rollback: + if (partial && result == ISC_R_NOSPACE) { + INSIST(rrbuffer.used < 65536); + dns_compress_rollback(cctx, (uint16_t)rrbuffer.used); + *countp += added; + *target = rrbuffer; + goto cleanup; + } + INSIST(savedbuffer.used < 65536); + dns_compress_rollback(cctx, (uint16_t)savedbuffer.used); + *countp = 0; + *target = savedbuffer; + +cleanup: + if (out != NULL && out != out_fixed) { + isc_mem_put(cctx->mctx, out, count * sizeof(*out)); + } + if (in != NULL && in != in_fixed) { + isc_mem_put(cctx->mctx, in, count * sizeof(*in)); + } + return (result); +} + +isc_result_t +dns_rdataset_towiresorted(dns_rdataset_t *rdataset, + const dns_name_t *owner_name, dns_compress_t *cctx, + isc_buffer_t *target, dns_rdatasetorderfunc_t order, + const void *order_arg, unsigned int options, + unsigned int *countp) { + return (towiresorted(rdataset, owner_name, cctx, target, order, + order_arg, false, options, countp, NULL)); +} + +isc_result_t +dns_rdataset_towirepartial(dns_rdataset_t *rdataset, + const dns_name_t *owner_name, dns_compress_t *cctx, + isc_buffer_t *target, dns_rdatasetorderfunc_t order, + const void *order_arg, unsigned int options, + unsigned int *countp, void **state) { + REQUIRE(state == NULL); /* XXX remove when implemented */ + return (towiresorted(rdataset, owner_name, cctx, target, order, + order_arg, true, options, countp, state)); +} + +isc_result_t +dns_rdataset_towire(dns_rdataset_t *rdataset, const dns_name_t *owner_name, + dns_compress_t *cctx, isc_buffer_t *target, + unsigned int options, unsigned int *countp) { + return (towiresorted(rdataset, owner_name, cctx, target, NULL, NULL, + false, options, countp, NULL)); +} + +isc_result_t +dns_rdataset_additionaldata(dns_rdataset_t *rdataset, + const dns_name_t *owner_name, + dns_additionaldatafunc_t add, void *arg) { + dns_rdata_t rdata = DNS_RDATA_INIT; + isc_result_t result; + + /* + * For each rdata in rdataset, call 'add' for each name and type in the + * rdata which is subject to additional section processing. + */ + + REQUIRE(DNS_RDATASET_VALID(rdataset)); + REQUIRE((rdataset->attributes & DNS_RDATASETATTR_QUESTION) == 0); + + result = dns_rdataset_first(rdataset); + if (result != ISC_R_SUCCESS) { + return (result); + } + + do { + dns_rdataset_current(rdataset, &rdata); + result = dns_rdata_additionaldata(&rdata, owner_name, add, arg); + if (result == ISC_R_SUCCESS) { + result = dns_rdataset_next(rdataset); + } + dns_rdata_reset(&rdata); + } while (result == ISC_R_SUCCESS); + + if (result != ISC_R_NOMORE) { + return (result); + } + + return (ISC_R_SUCCESS); +} + +isc_result_t +dns_rdataset_addnoqname(dns_rdataset_t *rdataset, dns_name_t *name) { + REQUIRE(DNS_RDATASET_VALID(rdataset)); + REQUIRE(rdataset->methods != NULL); + if (rdataset->methods->addnoqname == NULL) { + return (ISC_R_NOTIMPLEMENTED); + } + return ((rdataset->methods->addnoqname)(rdataset, name)); +} + +isc_result_t +dns_rdataset_getnoqname(dns_rdataset_t *rdataset, dns_name_t *name, + dns_rdataset_t *neg, dns_rdataset_t *negsig) { + REQUIRE(DNS_RDATASET_VALID(rdataset)); + REQUIRE(rdataset->methods != NULL); + + if (rdataset->methods->getnoqname == NULL) { + return (ISC_R_NOTIMPLEMENTED); + } + return ((rdataset->methods->getnoqname)(rdataset, name, neg, negsig)); +} + +isc_result_t +dns_rdataset_addclosest(dns_rdataset_t *rdataset, const dns_name_t *name) { + REQUIRE(DNS_RDATASET_VALID(rdataset)); + REQUIRE(rdataset->methods != NULL); + if (rdataset->methods->addclosest == NULL) { + return (ISC_R_NOTIMPLEMENTED); + } + return ((rdataset->methods->addclosest)(rdataset, name)); +} + +isc_result_t +dns_rdataset_getclosest(dns_rdataset_t *rdataset, dns_name_t *name, + dns_rdataset_t *neg, dns_rdataset_t *negsig) { + REQUIRE(DNS_RDATASET_VALID(rdataset)); + REQUIRE(rdataset->methods != NULL); + + if (rdataset->methods->getclosest == NULL) { + return (ISC_R_NOTIMPLEMENTED); + } + return ((rdataset->methods->getclosest)(rdataset, name, neg, negsig)); +} + +void +dns_rdataset_settrust(dns_rdataset_t *rdataset, dns_trust_t trust) { + REQUIRE(DNS_RDATASET_VALID(rdataset)); + REQUIRE(rdataset->methods != NULL); + + if (rdataset->methods->settrust != NULL) { + (rdataset->methods->settrust)(rdataset, trust); + } else { + rdataset->trust = trust; + } +} + +void +dns_rdataset_expire(dns_rdataset_t *rdataset) { + REQUIRE(DNS_RDATASET_VALID(rdataset)); + REQUIRE(rdataset->methods != NULL); + + if (rdataset->methods->expire != NULL) { + (rdataset->methods->expire)(rdataset); + } +} + +void +dns_rdataset_clearprefetch(dns_rdataset_t *rdataset) { + REQUIRE(DNS_RDATASET_VALID(rdataset)); + REQUIRE(rdataset->methods != NULL); + + if (rdataset->methods->clearprefetch != NULL) { + (rdataset->methods->clearprefetch)(rdataset); + } +} + +void +dns_rdataset_setownercase(dns_rdataset_t *rdataset, const dns_name_t *name) { + REQUIRE(DNS_RDATASET_VALID(rdataset)); + REQUIRE(rdataset->methods != NULL); + + if (rdataset->methods->setownercase != NULL) { + (rdataset->methods->setownercase)(rdataset, name); + } +} + +void +dns_rdataset_getownercase(const dns_rdataset_t *rdataset, dns_name_t *name) { + REQUIRE(DNS_RDATASET_VALID(rdataset)); + REQUIRE(rdataset->methods != NULL); + + if (rdataset->methods->getownercase != NULL) { + (rdataset->methods->getownercase)(rdataset, name); + } +} + +void +dns_rdataset_trimttl(dns_rdataset_t *rdataset, dns_rdataset_t *sigrdataset, + dns_rdata_rrsig_t *rrsig, isc_stdtime_t now, + bool acceptexpired) { + uint32_t ttl = 0; + + REQUIRE(DNS_RDATASET_VALID(rdataset)); + REQUIRE(DNS_RDATASET_VALID(sigrdataset)); + REQUIRE(rrsig != NULL); + + /* + * If we accept expired RRsets keep them for no more than 120 seconds. + */ + if (acceptexpired && + (isc_serial_le(rrsig->timeexpire, ((now + 120) & 0xffffffff)) || + isc_serial_le(rrsig->timeexpire, now))) + { + ttl = 120; + } else if (isc_serial_ge(rrsig->timeexpire, now)) { + ttl = rrsig->timeexpire - now; + } + + ttl = ISC_MIN(ISC_MIN(rdataset->ttl, sigrdataset->ttl), + ISC_MIN(rrsig->originalttl, ttl)); + rdataset->ttl = ttl; + sigrdataset->ttl = ttl; +} + +isc_result_t +dns_rdataset_addglue(dns_rdataset_t *rdataset, dns_dbversion_t *version, + dns_message_t *msg) { + REQUIRE(DNS_RDATASET_VALID(rdataset)); + REQUIRE(rdataset->methods != NULL); + REQUIRE(rdataset->type == dns_rdatatype_ns); + + if (rdataset->methods->addglue == NULL) { + return (ISC_R_NOTIMPLEMENTED); + } + + return ((rdataset->methods->addglue)(rdataset, version, msg)); +} |