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-rw-r--r--lib/dns/ncache.c777
1 files changed, 777 insertions, 0 deletions
diff --git a/lib/dns/ncache.c b/lib/dns/ncache.c
new file mode 100644
index 0000000..9247ac1
--- /dev/null
+++ b/lib/dns/ncache.c
@@ -0,0 +1,777 @@
+/*
+ * 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 <isc/buffer.h>
+#include <isc/util.h>
+
+#include <dns/db.h>
+#include <dns/message.h>
+#include <dns/ncache.h>
+#include <dns/rdata.h>
+#include <dns/rdatalist.h>
+#include <dns/rdataset.h>
+#include <dns/rdatastruct.h>
+
+#define DNS_NCACHE_RDATA 100U
+
+/*
+ * The format of an ncache rdata is a sequence of zero or more records of
+ * the following format:
+ *
+ * owner name
+ * type
+ * trust
+ * rdata count
+ * rdata length These two occur 'rdata count'
+ * rdata times.
+ *
+ */
+
+static isc_result_t
+addoptout(dns_message_t *message, dns_db_t *cache, dns_dbnode_t *node,
+ dns_rdatatype_t covers, isc_stdtime_t now, dns_ttl_t minttl,
+ dns_ttl_t maxttl, bool optout, bool secure,
+ dns_rdataset_t *addedrdataset);
+
+static isc_result_t
+copy_rdataset(dns_rdataset_t *rdataset, isc_buffer_t *buffer) {
+ isc_result_t result;
+ unsigned int count;
+ isc_region_t ar, r;
+ dns_rdata_t rdata = DNS_RDATA_INIT;
+
+ /*
+ * Copy the rdataset count to the buffer.
+ */
+ isc_buffer_availableregion(buffer, &ar);
+ if (ar.length < 2) {
+ return (ISC_R_NOSPACE);
+ }
+ count = dns_rdataset_count(rdataset);
+ INSIST(count <= 65535);
+ isc_buffer_putuint16(buffer, (uint16_t)count);
+
+ result = dns_rdataset_first(rdataset);
+ while (result == ISC_R_SUCCESS) {
+ dns_rdataset_current(rdataset, &rdata);
+ dns_rdata_toregion(&rdata, &r);
+ INSIST(r.length <= 65535);
+ isc_buffer_availableregion(buffer, &ar);
+ if (ar.length < 2) {
+ return (ISC_R_NOSPACE);
+ }
+ /*
+ * Copy the rdata length to the buffer.
+ */
+ isc_buffer_putuint16(buffer, (uint16_t)r.length);
+ /*
+ * Copy the rdata to the buffer.
+ */
+ result = isc_buffer_copyregion(buffer, &r);
+ if (result != ISC_R_SUCCESS) {
+ return (result);
+ }
+ dns_rdata_reset(&rdata);
+ result = dns_rdataset_next(rdataset);
+ }
+ if (result != ISC_R_NOMORE) {
+ return (result);
+ }
+
+ return (ISC_R_SUCCESS);
+}
+
+isc_result_t
+dns_ncache_add(dns_message_t *message, dns_db_t *cache, dns_dbnode_t *node,
+ dns_rdatatype_t covers, isc_stdtime_t now, dns_ttl_t minttl,
+ dns_ttl_t maxttl, dns_rdataset_t *addedrdataset) {
+ return (addoptout(message, cache, node, covers, now, minttl, maxttl,
+ false, false, addedrdataset));
+}
+
+isc_result_t
+dns_ncache_addoptout(dns_message_t *message, dns_db_t *cache,
+ dns_dbnode_t *node, dns_rdatatype_t covers,
+ isc_stdtime_t now, dns_ttl_t minttl, dns_ttl_t maxttl,
+ bool optout, dns_rdataset_t *addedrdataset) {
+ return (addoptout(message, cache, node, covers, now, minttl, maxttl,
+ optout, true, addedrdataset));
+}
+
+static isc_result_t
+addoptout(dns_message_t *message, dns_db_t *cache, dns_dbnode_t *node,
+ dns_rdatatype_t covers, isc_stdtime_t now, dns_ttl_t minttl,
+ dns_ttl_t maxttl, bool optout, bool secure,
+ dns_rdataset_t *addedrdataset) {
+ isc_result_t result;
+ isc_buffer_t buffer;
+ isc_region_t r;
+ dns_rdataset_t *rdataset;
+ dns_rdatatype_t type;
+ dns_name_t *name;
+ dns_ttl_t ttl;
+ dns_trust_t trust;
+ dns_rdata_t rdata[DNS_NCACHE_RDATA];
+ dns_rdataset_t ncrdataset;
+ dns_rdatalist_t ncrdatalist;
+ unsigned char data[65536];
+ unsigned int next = 0;
+
+ /*
+ * Convert the authority data from 'message' into a negative cache
+ * rdataset, and store it in 'cache' at 'node'.
+ */
+
+ REQUIRE(message != NULL);
+
+ /*
+ * We assume that all data in the authority section has been
+ * validated by the caller.
+ */
+
+ /*
+ * Initialize the list.
+ */
+ dns_rdatalist_init(&ncrdatalist);
+ ncrdatalist.rdclass = dns_db_class(cache);
+ ncrdatalist.covers = covers;
+ ncrdatalist.ttl = maxttl;
+
+ /*
+ * Build an ncache rdatas into buffer.
+ */
+ ttl = maxttl;
+ trust = 0xffff;
+ isc_buffer_init(&buffer, data, sizeof(data));
+ if (message->counts[DNS_SECTION_AUTHORITY]) {
+ result = dns_message_firstname(message, DNS_SECTION_AUTHORITY);
+ } else {
+ result = ISC_R_NOMORE;
+ }
+ while (result == ISC_R_SUCCESS) {
+ name = NULL;
+ dns_message_currentname(message, DNS_SECTION_AUTHORITY, &name);
+ if ((name->attributes & DNS_NAMEATTR_NCACHE) != 0) {
+ for (rdataset = ISC_LIST_HEAD(name->list);
+ rdataset != NULL;
+ rdataset = ISC_LIST_NEXT(rdataset, link))
+ {
+ if ((rdataset->attributes &
+ DNS_RDATASETATTR_NCACHE) == 0)
+ {
+ continue;
+ }
+ type = rdataset->type;
+ if (type == dns_rdatatype_rrsig) {
+ type = rdataset->covers;
+ }
+ if (type == dns_rdatatype_soa ||
+ type == dns_rdatatype_nsec ||
+ type == dns_rdatatype_nsec3)
+ {
+ if (ttl > rdataset->ttl) {
+ ttl = rdataset->ttl;
+ }
+ if (ttl < minttl) {
+ ttl = minttl;
+ }
+ if (trust > rdataset->trust) {
+ trust = rdataset->trust;
+ }
+ /*
+ * Copy the owner name to the buffer.
+ */
+ dns_name_toregion(name, &r);
+ result = isc_buffer_copyregion(&buffer,
+ &r);
+ if (result != ISC_R_SUCCESS) {
+ return (result);
+ }
+ /*
+ * Copy the type to the buffer.
+ */
+ isc_buffer_availableregion(&buffer, &r);
+ if (r.length < 3) {
+ return (ISC_R_NOSPACE);
+ }
+ isc_buffer_putuint16(&buffer,
+ rdataset->type);
+ isc_buffer_putuint8(
+ &buffer,
+ (unsigned char)rdataset->trust);
+ /*
+ * Copy the rdataset into the buffer.
+ */
+ result = copy_rdataset(rdataset,
+ &buffer);
+ if (result != ISC_R_SUCCESS) {
+ return (result);
+ }
+
+ if (next >= DNS_NCACHE_RDATA) {
+ return (ISC_R_NOSPACE);
+ }
+ dns_rdata_init(&rdata[next]);
+ isc_buffer_remainingregion(&buffer, &r);
+ rdata[next].data = r.base;
+ rdata[next].length = r.length;
+ rdata[next].rdclass =
+ ncrdatalist.rdclass;
+ rdata[next].type = 0;
+ rdata[next].flags = 0;
+ ISC_LIST_APPEND(ncrdatalist.rdata,
+ &rdata[next], link);
+ isc_buffer_forward(&buffer, r.length);
+ next++;
+ }
+ }
+ }
+ result = dns_message_nextname(message, DNS_SECTION_AUTHORITY);
+ }
+ if (result != ISC_R_NOMORE) {
+ return (result);
+ }
+
+ if (trust == 0xffff) {
+ if ((message->flags & DNS_MESSAGEFLAG_AA) != 0 &&
+ message->counts[DNS_SECTION_ANSWER] == 0)
+ {
+ /*
+ * The response has aa set and we haven't followed
+ * any CNAME or DNAME chains.
+ */
+ trust = dns_trust_authauthority;
+ } else {
+ trust = dns_trust_additional;
+ }
+ ttl = 0;
+ }
+
+ INSIST(trust != 0xffff);
+
+ ncrdatalist.ttl = ttl;
+
+ dns_rdataset_init(&ncrdataset);
+ RUNTIME_CHECK(dns_rdatalist_tordataset(&ncrdatalist, &ncrdataset) ==
+ ISC_R_SUCCESS);
+ if (!secure && trust > dns_trust_answer) {
+ trust = dns_trust_answer;
+ }
+ ncrdataset.trust = trust;
+ ncrdataset.attributes |= DNS_RDATASETATTR_NEGATIVE;
+ if (message->rcode == dns_rcode_nxdomain) {
+ ncrdataset.attributes |= DNS_RDATASETATTR_NXDOMAIN;
+ }
+ if (optout) {
+ ncrdataset.attributes |= DNS_RDATASETATTR_OPTOUT;
+ }
+
+ return (dns_db_addrdataset(cache, node, NULL, now, &ncrdataset, 0,
+ addedrdataset));
+}
+
+isc_result_t
+dns_ncache_towire(dns_rdataset_t *rdataset, dns_compress_t *cctx,
+ isc_buffer_t *target, unsigned int options,
+ unsigned int *countp) {
+ dns_rdata_t rdata = DNS_RDATA_INIT;
+ isc_result_t result;
+ isc_region_t remaining, tavailable;
+ isc_buffer_t source, savedbuffer, rdlen;
+ dns_name_t name;
+ dns_rdatatype_t type;
+ unsigned int i, rcount, count;
+
+ /*
+ * Convert the negative caching rdataset 'rdataset' to wire format,
+ * compressing names as specified in 'cctx', and storing the result in
+ * 'target'.
+ */
+
+ REQUIRE(rdataset != NULL);
+ REQUIRE(rdataset->type == 0);
+ REQUIRE((rdataset->attributes & DNS_RDATASETATTR_NEGATIVE) != 0);
+
+ savedbuffer = *target;
+ count = 0;
+
+ result = dns_rdataset_first(rdataset);
+ while (result == ISC_R_SUCCESS) {
+ dns_rdataset_current(rdataset, &rdata);
+ isc_buffer_init(&source, rdata.data, rdata.length);
+ isc_buffer_add(&source, rdata.length);
+ dns_name_init(&name, NULL);
+ isc_buffer_remainingregion(&source, &remaining);
+ dns_name_fromregion(&name, &remaining);
+ INSIST(remaining.length >= name.length);
+ isc_buffer_forward(&source, name.length);
+ remaining.length -= name.length;
+
+ INSIST(remaining.length >= 5);
+ type = isc_buffer_getuint16(&source);
+ isc_buffer_forward(&source, 1);
+ rcount = isc_buffer_getuint16(&source);
+
+ for (i = 0; i < rcount; i++) {
+ /*
+ * Get the length of this rdata and set up an
+ * rdata structure for it.
+ */
+ isc_buffer_remainingregion(&source, &remaining);
+ INSIST(remaining.length >= 2);
+ dns_rdata_reset(&rdata);
+ rdata.length = isc_buffer_getuint16(&source);
+ isc_buffer_remainingregion(&source, &remaining);
+ rdata.data = remaining.base;
+ rdata.type = type;
+ rdata.rdclass = rdataset->rdclass;
+ INSIST(remaining.length >= rdata.length);
+ isc_buffer_forward(&source, rdata.length);
+
+ if ((options & DNS_NCACHETOWIRE_OMITDNSSEC) != 0 &&
+ dns_rdatatype_isdnssec(type))
+ {
+ continue;
+ }
+
+ /*
+ * Write the name.
+ */
+ dns_compress_setmethods(cctx, DNS_COMPRESS_GLOBAL14);
+ result = dns_name_towire(&name, cctx, target);
+ if (result != ISC_R_SUCCESS) {
+ goto rollback;
+ }
+
+ /*
+ * See if we have space for type, class, ttl, and
+ * rdata length. Write the type, class, and ttl.
+ */
+ isc_buffer_availableregion(target, &tavailable);
+ if (tavailable.length < 10) {
+ result = ISC_R_NOSPACE;
+ goto rollback;
+ }
+ isc_buffer_putuint16(target, type);
+ isc_buffer_putuint16(target, rdataset->rdclass);
+ isc_buffer_putuint32(target, rdataset->ttl);
+
+ /*
+ * Save space for rdata length.
+ */
+ rdlen = *target;
+ isc_buffer_add(target, 2);
+
+ /*
+ * Write the rdata.
+ */
+ result = dns_rdata_towire(&rdata, cctx, target);
+ if (result != ISC_R_SUCCESS) {
+ goto rollback;
+ }
+
+ /*
+ * Set the rdata length field to the compressed
+ * length.
+ */
+ INSIST((target->used >= rdlen.used + 2) &&
+ (target->used - rdlen.used - 2 < 65536));
+ isc_buffer_putuint16(
+ &rdlen,
+ (uint16_t)(target->used - rdlen.used - 2));
+
+ count++;
+ }
+ INSIST(isc_buffer_remaininglength(&source) == 0);
+ result = dns_rdataset_next(rdataset);
+ dns_rdata_reset(&rdata);
+ }
+ if (result != ISC_R_NOMORE) {
+ goto rollback;
+ }
+
+ *countp = count;
+
+ return (ISC_R_SUCCESS);
+
+rollback:
+ INSIST(savedbuffer.used < 65536);
+ dns_compress_rollback(cctx, (uint16_t)savedbuffer.used);
+ *countp = 0;
+ *target = savedbuffer;
+
+ return (result);
+}
+
+static void
+rdataset_disassociate(dns_rdataset_t *rdataset) {
+ UNUSED(rdataset);
+}
+
+static isc_result_t
+rdataset_first(dns_rdataset_t *rdataset) {
+ unsigned char *raw = rdataset->private3;
+ unsigned int count;
+
+ count = raw[0] * 256 + raw[1];
+ if (count == 0) {
+ rdataset->private5 = NULL;
+ return (ISC_R_NOMORE);
+ }
+ raw += 2;
+ /*
+ * The privateuint4 field is the number of rdata beyond the cursor
+ * position, so we decrement the total count by one before storing
+ * it.
+ */
+ count--;
+ rdataset->privateuint4 = count;
+ rdataset->private5 = raw;
+
+ return (ISC_R_SUCCESS);
+}
+
+static isc_result_t
+rdataset_next(dns_rdataset_t *rdataset) {
+ unsigned int count;
+ unsigned int length;
+ unsigned char *raw;
+
+ count = rdataset->privateuint4;
+ if (count == 0) {
+ return (ISC_R_NOMORE);
+ }
+ count--;
+ rdataset->privateuint4 = count;
+ raw = rdataset->private5;
+ length = raw[0] * 256 + raw[1];
+ raw += length + 2;
+ rdataset->private5 = raw;
+
+ return (ISC_R_SUCCESS);
+}
+
+static void
+rdataset_current(dns_rdataset_t *rdataset, dns_rdata_t *rdata) {
+ unsigned char *raw = rdataset->private5;
+ isc_region_t r;
+
+ REQUIRE(raw != NULL);
+
+ r.length = raw[0] * 256 + raw[1];
+ raw += 2;
+ r.base = raw;
+ dns_rdata_fromregion(rdata, rdataset->rdclass, rdataset->type, &r);
+}
+
+static void
+rdataset_clone(dns_rdataset_t *source, dns_rdataset_t *target) {
+ *target = *source;
+
+ /*
+ * Reset iterator state.
+ */
+ target->privateuint4 = 0;
+ target->private5 = NULL;
+}
+
+static unsigned int
+rdataset_count(dns_rdataset_t *rdataset) {
+ unsigned char *raw = rdataset->private3;
+ unsigned int count;
+
+ count = raw[0] * 256 + raw[1];
+
+ return (count);
+}
+
+static void
+rdataset_settrust(dns_rdataset_t *rdataset, dns_trust_t trust) {
+ unsigned char *raw = rdataset->private3;
+
+ raw[-1] = (unsigned char)trust;
+ rdataset->trust = trust;
+}
+
+static dns_rdatasetmethods_t rdataset_methods = {
+ rdataset_disassociate,
+ rdataset_first,
+ rdataset_next,
+ rdataset_current,
+ rdataset_clone,
+ rdataset_count,
+ NULL, /* addnoqname */
+ NULL, /* getnoqname */
+ NULL, /* addclosest */
+ NULL, /* getclosest */
+ rdataset_settrust, /* settrust */
+ NULL, /* expire */
+ NULL, /* clearprefetch */
+ NULL, /* setownercase */
+ NULL, /* getownercase */
+ NULL /* addglue */
+};
+
+isc_result_t
+dns_ncache_getrdataset(dns_rdataset_t *ncacherdataset, dns_name_t *name,
+ dns_rdatatype_t type, dns_rdataset_t *rdataset) {
+ isc_result_t result;
+ dns_rdata_t rdata = DNS_RDATA_INIT;
+ isc_region_t remaining;
+ isc_buffer_t source;
+ dns_name_t tname;
+ dns_rdatatype_t ttype;
+ dns_trust_t trust = dns_trust_none;
+ dns_rdataset_t rclone;
+
+ REQUIRE(ncacherdataset != NULL);
+ REQUIRE(ncacherdataset->type == 0);
+ REQUIRE((ncacherdataset->attributes & DNS_RDATASETATTR_NEGATIVE) != 0);
+ REQUIRE(name != NULL);
+ REQUIRE(!dns_rdataset_isassociated(rdataset));
+ REQUIRE(type != dns_rdatatype_rrsig);
+
+ dns_rdataset_init(&rclone);
+ dns_rdataset_clone(ncacherdataset, &rclone);
+ result = dns_rdataset_first(&rclone);
+ while (result == ISC_R_SUCCESS) {
+ dns_rdataset_current(&rclone, &rdata);
+ isc_buffer_init(&source, rdata.data, rdata.length);
+ isc_buffer_add(&source, rdata.length);
+ dns_name_init(&tname, NULL);
+ isc_buffer_remainingregion(&source, &remaining);
+ dns_name_fromregion(&tname, &remaining);
+ INSIST(remaining.length >= tname.length);
+ isc_buffer_forward(&source, tname.length);
+ remaining.length -= tname.length;
+
+ INSIST(remaining.length >= 3);
+ ttype = isc_buffer_getuint16(&source);
+
+ if (ttype == type && dns_name_equal(&tname, name)) {
+ trust = isc_buffer_getuint8(&source);
+ INSIST(trust <= dns_trust_ultimate);
+ isc_buffer_remainingregion(&source, &remaining);
+ break;
+ }
+ result = dns_rdataset_next(&rclone);
+ dns_rdata_reset(&rdata);
+ }
+ dns_rdataset_disassociate(&rclone);
+ if (result == ISC_R_NOMORE) {
+ return (ISC_R_NOTFOUND);
+ }
+ if (result != ISC_R_SUCCESS) {
+ return (result);
+ }
+
+ INSIST(remaining.length != 0);
+
+ rdataset->methods = &rdataset_methods;
+ rdataset->rdclass = ncacherdataset->rdclass;
+ rdataset->type = type;
+ rdataset->covers = 0;
+ rdataset->ttl = ncacherdataset->ttl;
+ rdataset->trust = trust;
+ rdataset->private1 = NULL;
+ rdataset->private2 = NULL;
+
+ rdataset->private3 = remaining.base;
+
+ /*
+ * Reset iterator state.
+ */
+ rdataset->privateuint4 = 0;
+ rdataset->private5 = NULL;
+ rdataset->private6 = NULL;
+ return (ISC_R_SUCCESS);
+}
+
+isc_result_t
+dns_ncache_getsigrdataset(dns_rdataset_t *ncacherdataset, dns_name_t *name,
+ dns_rdatatype_t covers, dns_rdataset_t *rdataset) {
+ dns_name_t tname;
+ dns_rdata_rrsig_t rrsig;
+ dns_rdata_t rdata = DNS_RDATA_INIT;
+ dns_rdataset_t rclone;
+ dns_rdatatype_t type;
+ dns_trust_t trust = dns_trust_none;
+ isc_buffer_t source;
+ isc_region_t remaining, sigregion;
+ isc_result_t result;
+ unsigned char *raw;
+ unsigned int count;
+
+ REQUIRE(ncacherdataset != NULL);
+ REQUIRE(ncacherdataset->type == 0);
+ REQUIRE((ncacherdataset->attributes & DNS_RDATASETATTR_NEGATIVE) != 0);
+ REQUIRE(name != NULL);
+ REQUIRE(!dns_rdataset_isassociated(rdataset));
+
+ dns_rdataset_init(&rclone);
+ dns_rdataset_clone(ncacherdataset, &rclone);
+ result = dns_rdataset_first(&rclone);
+ while (result == ISC_R_SUCCESS) {
+ dns_rdataset_current(&rclone, &rdata);
+ isc_buffer_init(&source, rdata.data, rdata.length);
+ isc_buffer_add(&source, rdata.length);
+ dns_name_init(&tname, NULL);
+ isc_buffer_remainingregion(&source, &remaining);
+ dns_name_fromregion(&tname, &remaining);
+ INSIST(remaining.length >= tname.length);
+ isc_buffer_forward(&source, tname.length);
+ isc_region_consume(&remaining, tname.length);
+
+ INSIST(remaining.length >= 2);
+ type = isc_buffer_getuint16(&source);
+ isc_region_consume(&remaining, 2);
+
+ if (type != dns_rdatatype_rrsig ||
+ !dns_name_equal(&tname, name))
+ {
+ result = dns_rdataset_next(&rclone);
+ dns_rdata_reset(&rdata);
+ continue;
+ }
+
+ INSIST(remaining.length >= 1);
+ trust = isc_buffer_getuint8(&source);
+ INSIST(trust <= dns_trust_ultimate);
+ isc_region_consume(&remaining, 1);
+
+ raw = remaining.base;
+ count = raw[0] * 256 + raw[1];
+ INSIST(count > 0);
+ raw += 2;
+ sigregion.length = raw[0] * 256 + raw[1];
+ raw += 2;
+ sigregion.base = raw;
+ dns_rdata_reset(&rdata);
+ dns_rdata_fromregion(&rdata, rdataset->rdclass,
+ dns_rdatatype_rrsig, &sigregion);
+ (void)dns_rdata_tostruct(&rdata, &rrsig, NULL);
+ if (rrsig.covered == covers) {
+ isc_buffer_remainingregion(&source, &remaining);
+ break;
+ }
+
+ result = dns_rdataset_next(&rclone);
+ dns_rdata_reset(&rdata);
+ }
+ dns_rdataset_disassociate(&rclone);
+ if (result == ISC_R_NOMORE) {
+ return (ISC_R_NOTFOUND);
+ }
+ if (result != ISC_R_SUCCESS) {
+ return (result);
+ }
+
+ INSIST(remaining.length != 0);
+
+ rdataset->methods = &rdataset_methods;
+ rdataset->rdclass = ncacherdataset->rdclass;
+ rdataset->type = dns_rdatatype_rrsig;
+ rdataset->covers = covers;
+ rdataset->ttl = ncacherdataset->ttl;
+ rdataset->trust = trust;
+ rdataset->private1 = NULL;
+ rdataset->private2 = NULL;
+
+ rdataset->private3 = remaining.base;
+
+ /*
+ * Reset iterator state.
+ */
+ rdataset->privateuint4 = 0;
+ rdataset->private5 = NULL;
+ rdataset->private6 = NULL;
+ return (ISC_R_SUCCESS);
+}
+
+void
+dns_ncache_current(dns_rdataset_t *ncacherdataset, dns_name_t *found,
+ dns_rdataset_t *rdataset) {
+ dns_rdata_t rdata = DNS_RDATA_INIT;
+ dns_trust_t trust;
+ isc_region_t remaining, sigregion;
+ isc_buffer_t source;
+ dns_name_t tname;
+ dns_rdatatype_t type;
+ unsigned int count;
+ dns_rdata_rrsig_t rrsig;
+ unsigned char *raw;
+
+ REQUIRE(ncacherdataset != NULL);
+ REQUIRE(ncacherdataset->type == 0);
+ REQUIRE((ncacherdataset->attributes & DNS_RDATASETATTR_NEGATIVE) != 0);
+ REQUIRE(found != NULL);
+ REQUIRE(!dns_rdataset_isassociated(rdataset));
+
+ dns_rdataset_current(ncacherdataset, &rdata);
+ isc_buffer_init(&source, rdata.data, rdata.length);
+ isc_buffer_add(&source, rdata.length);
+
+ dns_name_init(&tname, NULL);
+ isc_buffer_remainingregion(&source, &remaining);
+ dns_name_fromregion(found, &remaining);
+ INSIST(remaining.length >= found->length);
+ isc_buffer_forward(&source, found->length);
+ remaining.length -= found->length;
+
+ INSIST(remaining.length >= 5);
+ type = isc_buffer_getuint16(&source);
+ trust = isc_buffer_getuint8(&source);
+ INSIST(trust <= dns_trust_ultimate);
+ isc_buffer_remainingregion(&source, &remaining);
+
+ rdataset->methods = &rdataset_methods;
+ rdataset->rdclass = ncacherdataset->rdclass;
+ rdataset->type = type;
+ if (type == dns_rdatatype_rrsig) {
+ /*
+ * Extract covers from RRSIG.
+ */
+ raw = remaining.base;
+ count = raw[0] * 256 + raw[1];
+ INSIST(count > 0);
+ raw += 2;
+ sigregion.length = raw[0] * 256 + raw[1];
+ raw += 2;
+ sigregion.base = raw;
+ dns_rdata_reset(&rdata);
+ dns_rdata_fromregion(&rdata, rdataset->rdclass, rdataset->type,
+ &sigregion);
+ (void)dns_rdata_tostruct(&rdata, &rrsig, NULL);
+ rdataset->covers = rrsig.covered;
+ } else {
+ rdataset->covers = 0;
+ }
+ rdataset->ttl = ncacherdataset->ttl;
+ rdataset->trust = trust;
+ rdataset->private1 = NULL;
+ rdataset->private2 = NULL;
+
+ rdataset->private3 = remaining.base;
+
+ /*
+ * Reset iterator state.
+ */
+ rdataset->privateuint4 = 0;
+ rdataset->private5 = NULL;
+ rdataset->private6 = NULL;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-23 00:53:40 +0000