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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 07:24:22 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 07:24:22 +0000
commit45d6379135504814ab723b57f0eb8be23393a51d (patch)
treed4f2ec4acca824a8446387a758b0ce4238a4dffa /lib/dns/ecdb.c
parentInitial commit. (diff)
downloadbind9-45d6379135504814ab723b57f0eb8be23393a51d.tar.xz
bind9-45d6379135504814ab723b57f0eb8be23393a51d.zip
Adding upstream version 1:9.16.44.upstream/1%9.16.44
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'lib/dns/ecdb.c')
-rw-r--r--lib/dns/ecdb.c797
1 files changed, 797 insertions, 0 deletions
diff --git a/lib/dns/ecdb.c b/lib/dns/ecdb.c
new file mode 100644
index 0000000..abbb8d9
--- /dev/null
+++ b/lib/dns/ecdb.c
@@ -0,0 +1,797 @@
+/*
+ * 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.
+ */
+
+#include <stdbool.h>
+
+#include <isc/mem.h>
+#include <isc/mutex.h>
+#include <isc/refcount.h>
+#include <isc/result.h>
+#include <isc/util.h>
+
+#include <dns/db.h>
+#include <dns/ecdb.h>
+#include <dns/rdata.h>
+#include <dns/rdataset.h>
+#include <dns/rdatasetiter.h>
+#include <dns/rdataslab.h>
+
+#define ECDB_MAGIC ISC_MAGIC('E', 'C', 'D', 'B')
+#define VALID_ECDB(db) ((db) != NULL && (db)->common.impmagic == ECDB_MAGIC)
+
+#define ECDBNODE_MAGIC ISC_MAGIC('E', 'C', 'D', 'N')
+#define VALID_ECDBNODE(ecdbn) ISC_MAGIC_VALID(ecdbn, ECDBNODE_MAGIC)
+
+/*%
+ * The 'ephemeral' cache DB (ecdb) implementation. An ecdb just provides
+ * temporary storage for ongoing name resolution with the common DB interfaces.
+ * It actually doesn't cache anything. The implementation expects any stored
+ * data is released within a short period, and does not care about the
+ * scalability in terms of the number of nodes.
+ */
+
+typedef struct dns_ecdb {
+ /* Unlocked */
+ dns_db_t common;
+ isc_mutex_t lock;
+
+ /* Protected by atomics */
+ isc_refcount_t references;
+
+ /* Locked */
+ ISC_LIST(struct dns_ecdbnode) nodes;
+} dns_ecdb_t;
+
+typedef struct dns_ecdbnode {
+ /* Unlocked */
+ unsigned int magic;
+ isc_mutex_t lock;
+ dns_ecdb_t *ecdb;
+ dns_name_t name;
+ ISC_LINK(struct dns_ecdbnode) link;
+
+ /* Locked */
+ ISC_LIST(struct rdatasetheader) rdatasets;
+
+ /* Protected by atomics */
+ isc_refcount_t references;
+} dns_ecdbnode_t;
+
+typedef struct rdatasetheader {
+ dns_rdatatype_t type;
+ dns_ttl_t ttl;
+ dns_trust_t trust;
+ dns_rdatatype_t covers;
+ unsigned int attributes;
+
+ ISC_LINK(struct rdatasetheader) link;
+} rdatasetheader_t;
+
+/* Copied from rbtdb.c */
+#define RDATASET_ATTR_NXDOMAIN 0x0010
+#define RDATASET_ATTR_NEGATIVE 0x0100
+#define NXDOMAIN(header) (((header)->attributes & RDATASET_ATTR_NXDOMAIN) != 0)
+#define NEGATIVE(header) (((header)->attributes & RDATASET_ATTR_NEGATIVE) != 0)
+
+static isc_result_t
+dns_ecdb_create(isc_mem_t *mctx, const dns_name_t *origin, dns_dbtype_t type,
+ dns_rdataclass_t rdclass, unsigned int argc, char *argv[],
+ void *driverarg, dns_db_t **dbp);
+
+static void
+rdataset_disassociate(dns_rdataset_t *rdataset);
+static isc_result_t
+rdataset_first(dns_rdataset_t *rdataset);
+static isc_result_t
+rdataset_next(dns_rdataset_t *rdataset);
+static void
+rdataset_current(dns_rdataset_t *rdataset, dns_rdata_t *rdata);
+static void
+rdataset_clone(dns_rdataset_t *source, dns_rdataset_t *target);
+static unsigned int
+rdataset_count(dns_rdataset_t *rdataset);
+static void
+rdataset_settrust(dns_rdataset_t *rdataset, dns_trust_t 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 */
+};
+
+typedef struct ecdb_rdatasetiter {
+ dns_rdatasetiter_t common;
+ rdatasetheader_t *current;
+} ecdb_rdatasetiter_t;
+
+static void
+rdatasetiter_destroy(dns_rdatasetiter_t **iteratorp);
+static isc_result_t
+rdatasetiter_first(dns_rdatasetiter_t *iterator);
+static isc_result_t
+rdatasetiter_next(dns_rdatasetiter_t *iterator);
+static void
+rdatasetiter_current(dns_rdatasetiter_t *iterator, dns_rdataset_t *rdataset);
+
+static dns_rdatasetitermethods_t rdatasetiter_methods = {
+ rdatasetiter_destroy, rdatasetiter_first, rdatasetiter_next,
+ rdatasetiter_current
+};
+
+isc_result_t
+dns_ecdb_register(isc_mem_t *mctx, dns_dbimplementation_t **dbimp) {
+ REQUIRE(mctx != NULL);
+ REQUIRE(dbimp != NULL && *dbimp == NULL);
+
+ return (dns_db_register("ecdb", dns_ecdb_create, NULL, mctx, dbimp));
+}
+
+void
+dns_ecdb_unregister(dns_dbimplementation_t **dbimp) {
+ REQUIRE(dbimp != NULL && *dbimp != NULL);
+
+ dns_db_unregister(dbimp);
+}
+
+/*%
+ * DB routines
+ */
+
+static void
+attach(dns_db_t *source, dns_db_t **targetp) {
+ dns_ecdb_t *ecdb = (dns_ecdb_t *)source;
+
+ REQUIRE(VALID_ECDB(ecdb));
+ REQUIRE(targetp != NULL && *targetp == NULL);
+
+ isc_refcount_increment(&ecdb->references);
+
+ *targetp = source;
+}
+
+static void
+destroy_ecdb(dns_ecdb_t *ecdb) {
+ if (isc_refcount_decrement(&ecdb->references) == 1) {
+ isc_refcount_destroy(&ecdb->references);
+
+ INSIST(ISC_LIST_EMPTY(ecdb->nodes));
+
+ if (dns_name_dynamic(&ecdb->common.origin)) {
+ dns_name_free(&ecdb->common.origin, ecdb->common.mctx);
+ }
+
+ isc_mutex_destroy(&ecdb->lock);
+
+ ecdb->common.impmagic = 0;
+ ecdb->common.magic = 0;
+
+ isc_mem_putanddetach(&ecdb->common.mctx, ecdb, sizeof(*ecdb));
+ }
+}
+
+static void
+detach(dns_db_t **dbp) {
+ dns_ecdb_t *ecdb;
+
+ REQUIRE(dbp != NULL);
+ ecdb = (dns_ecdb_t *)*dbp;
+ REQUIRE(VALID_ECDB(ecdb));
+
+ *dbp = NULL;
+
+ destroy_ecdb(ecdb);
+}
+
+static void
+attachnode(dns_db_t *db, dns_dbnode_t *source, dns_dbnode_t **targetp) {
+ dns_ecdb_t *ecdb = (dns_ecdb_t *)db;
+ dns_ecdbnode_t *node = (dns_ecdbnode_t *)source;
+
+ REQUIRE(VALID_ECDB(ecdb));
+ REQUIRE(VALID_ECDBNODE(node));
+ REQUIRE(targetp != NULL && *targetp == NULL);
+
+ isc_refcount_increment(&node->references);
+ isc_refcount_increment(&node->references);
+
+ *targetp = node;
+}
+
+static void
+destroynode(dns_ecdbnode_t *node) {
+ isc_mem_t *mctx;
+ dns_ecdb_t *ecdb = node->ecdb;
+ rdatasetheader_t *header;
+
+ mctx = ecdb->common.mctx;
+
+ LOCK(&ecdb->lock);
+ ISC_LIST_UNLINK(ecdb->nodes, node, link);
+ UNLOCK(&ecdb->lock);
+
+ dns_name_free(&node->name, mctx);
+
+ while ((header = ISC_LIST_HEAD(node->rdatasets)) != NULL) {
+ unsigned int headersize;
+
+ ISC_LIST_UNLINK(node->rdatasets, header, link);
+ headersize = dns_rdataslab_size((unsigned char *)header,
+ sizeof(*header));
+ isc_mem_put(mctx, header, headersize);
+ }
+
+ isc_mutex_destroy(&node->lock);
+ isc_refcount_destroy(&node->references);
+
+ node->magic = 0;
+ isc_mem_put(mctx, node, sizeof(*node));
+
+ destroy_ecdb(ecdb);
+}
+
+static void
+detachnode(dns_db_t *db, dns_dbnode_t **nodep) {
+ dns_ecdb_t *ecdb = (dns_ecdb_t *)db;
+ dns_ecdbnode_t *node;
+
+ REQUIRE(VALID_ECDB(ecdb));
+ REQUIRE(nodep != NULL);
+ node = (dns_ecdbnode_t *)*nodep;
+ REQUIRE(VALID_ECDBNODE(node));
+ *nodep = NULL;
+
+ if (isc_refcount_decrement(&node->references) == 1) {
+ destroynode(node);
+ }
+}
+
+static isc_result_t
+find(dns_db_t *db, const dns_name_t *name, dns_dbversion_t *version,
+ dns_rdatatype_t type, unsigned int options, isc_stdtime_t now,
+ dns_dbnode_t **nodep, dns_name_t *foundname, dns_rdataset_t *rdataset,
+ dns_rdataset_t *sigrdataset) {
+ dns_ecdb_t *ecdb = (dns_ecdb_t *)db;
+
+ REQUIRE(VALID_ECDB(ecdb));
+
+ UNUSED(name);
+ UNUSED(version);
+ UNUSED(type);
+ UNUSED(options);
+ UNUSED(now);
+ UNUSED(nodep);
+ UNUSED(foundname);
+ UNUSED(rdataset);
+ UNUSED(sigrdataset);
+
+ return (ISC_R_NOTFOUND);
+}
+
+static isc_result_t
+findzonecut(dns_db_t *db, const dns_name_t *name, unsigned int options,
+ isc_stdtime_t now, dns_dbnode_t **nodep, dns_name_t *foundname,
+ dns_name_t *dcname, dns_rdataset_t *rdataset,
+ dns_rdataset_t *sigrdataset) {
+ dns_ecdb_t *ecdb = (dns_ecdb_t *)db;
+
+ REQUIRE(VALID_ECDB(ecdb));
+
+ UNUSED(name);
+ UNUSED(options);
+ UNUSED(now);
+ UNUSED(nodep);
+ UNUSED(foundname);
+ UNUSED(dcname);
+ UNUSED(rdataset);
+ UNUSED(sigrdataset);
+
+ return (ISC_R_NOTFOUND);
+}
+
+static isc_result_t
+findnode(dns_db_t *db, const dns_name_t *name, bool create,
+ dns_dbnode_t **nodep) {
+ dns_ecdb_t *ecdb = (dns_ecdb_t *)db;
+ isc_mem_t *mctx;
+ dns_ecdbnode_t *node;
+
+ REQUIRE(VALID_ECDB(ecdb));
+ REQUIRE(nodep != NULL && *nodep == NULL);
+
+ UNUSED(name);
+
+ if (create != true) {
+ /* an 'ephemeral' node is never reused. */
+ return (ISC_R_NOTFOUND);
+ }
+
+ mctx = ecdb->common.mctx;
+ node = isc_mem_get(mctx, sizeof(*node));
+
+ isc_mutex_init(&node->lock);
+
+ dns_name_init(&node->name, NULL);
+ dns_name_dup(name, mctx, &node->name);
+
+ isc_refcount_init(&node->references, 1);
+ ISC_LIST_INIT(node->rdatasets);
+
+ ISC_LINK_INIT(node, link);
+
+ isc_refcount_increment(&ecdb->references);
+ node->ecdb = ecdb;
+
+ LOCK(&ecdb->lock);
+ ISC_LIST_APPEND(ecdb->nodes, node, link);
+ UNLOCK(&ecdb->lock);
+
+ node->magic = ECDBNODE_MAGIC;
+
+ *nodep = node;
+
+ return (ISC_R_SUCCESS);
+}
+
+static void
+bind_rdataset(dns_ecdb_t *ecdb, dns_ecdbnode_t *node, rdatasetheader_t *header,
+ dns_rdataset_t *rdataset) {
+ unsigned char *raw;
+
+ /*
+ * Caller must be holding the node lock.
+ */
+
+ REQUIRE(!dns_rdataset_isassociated(rdataset));
+
+ rdataset->methods = &rdataset_methods;
+ rdataset->rdclass = ecdb->common.rdclass;
+ rdataset->type = header->type;
+ rdataset->covers = header->covers;
+ rdataset->ttl = header->ttl;
+ rdataset->trust = header->trust;
+ if (NXDOMAIN(header)) {
+ rdataset->attributes |= DNS_RDATASETATTR_NXDOMAIN;
+ }
+ if (NEGATIVE(header)) {
+ rdataset->attributes |= DNS_RDATASETATTR_NEGATIVE;
+ }
+
+ rdataset->private1 = ecdb;
+ rdataset->private2 = node;
+ raw = (unsigned char *)header + sizeof(*header);
+ rdataset->private3 = raw;
+ rdataset->count = 0;
+
+ /*
+ * Reset iterator state.
+ */
+ rdataset->privateuint4 = 0;
+ rdataset->private5 = NULL;
+
+ isc_refcount_increment(&node->references);
+}
+
+static isc_result_t
+addrdataset(dns_db_t *db, dns_dbnode_t *node, dns_dbversion_t *version,
+ isc_stdtime_t now, dns_rdataset_t *rdataset, unsigned int options,
+ dns_rdataset_t *addedrdataset) {
+ dns_ecdb_t *ecdb = (dns_ecdb_t *)db;
+ isc_region_t r;
+ isc_result_t result = ISC_R_SUCCESS;
+ isc_mem_t *mctx;
+ dns_ecdbnode_t *ecdbnode = (dns_ecdbnode_t *)node;
+ rdatasetheader_t *header;
+
+ REQUIRE(VALID_ECDB(ecdb));
+ REQUIRE(VALID_ECDBNODE(ecdbnode));
+
+ UNUSED(version);
+ UNUSED(now);
+ UNUSED(options);
+
+ mctx = ecdb->common.mctx;
+
+ LOCK(&ecdbnode->lock);
+
+ /*
+ * Sanity check: this implementation does not allow overriding an
+ * existing rdataset of the same type.
+ */
+ for (header = ISC_LIST_HEAD(ecdbnode->rdatasets); header != NULL;
+ header = ISC_LIST_NEXT(header, link))
+ {
+ INSIST(header->type != rdataset->type ||
+ header->covers != rdataset->covers);
+ }
+
+ result = dns_rdataslab_fromrdataset(rdataset, mctx, &r,
+ sizeof(rdatasetheader_t));
+ if (result != ISC_R_SUCCESS) {
+ goto unlock;
+ }
+
+ header = (rdatasetheader_t *)r.base;
+ header->type = rdataset->type;
+ header->ttl = rdataset->ttl;
+ header->trust = rdataset->trust;
+ header->covers = rdataset->covers;
+ header->attributes = 0;
+ if ((rdataset->attributes & DNS_RDATASETATTR_NXDOMAIN) != 0) {
+ header->attributes |= RDATASET_ATTR_NXDOMAIN;
+ }
+ if ((rdataset->attributes & DNS_RDATASETATTR_NEGATIVE) != 0) {
+ header->attributes |= RDATASET_ATTR_NEGATIVE;
+ }
+ ISC_LINK_INIT(header, link);
+ ISC_LIST_APPEND(ecdbnode->rdatasets, header, link);
+
+ if (addedrdataset == NULL) {
+ goto unlock;
+ }
+
+ bind_rdataset(ecdb, ecdbnode, header, addedrdataset);
+
+unlock:
+ UNLOCK(&ecdbnode->lock);
+
+ return (result);
+}
+
+static isc_result_t
+deleterdataset(dns_db_t *db, dns_dbnode_t *node, dns_dbversion_t *version,
+ dns_rdatatype_t type, dns_rdatatype_t covers) {
+ UNUSED(db);
+ UNUSED(node);
+ UNUSED(version);
+ UNUSED(type);
+ UNUSED(covers);
+
+ return (ISC_R_NOTIMPLEMENTED);
+}
+
+static isc_result_t
+createiterator(dns_db_t *db, unsigned int options,
+ dns_dbiterator_t **iteratorp) {
+ UNUSED(db);
+ UNUSED(options);
+ UNUSED(iteratorp);
+
+ return (ISC_R_NOTIMPLEMENTED);
+}
+
+static isc_result_t
+allrdatasets(dns_db_t *db, dns_dbnode_t *node, dns_dbversion_t *version,
+ unsigned int options, isc_stdtime_t now,
+ dns_rdatasetiter_t **iteratorp) {
+ dns_ecdb_t *ecdb = (dns_ecdb_t *)db;
+ dns_ecdbnode_t *ecdbnode = (dns_ecdbnode_t *)node;
+ isc_mem_t *mctx;
+ ecdb_rdatasetiter_t *iterator;
+
+ REQUIRE(VALID_ECDB(ecdb));
+ REQUIRE(VALID_ECDBNODE(ecdbnode));
+
+ mctx = ecdb->common.mctx;
+
+ iterator = isc_mem_get(mctx, sizeof(ecdb_rdatasetiter_t));
+
+ iterator->common.magic = DNS_RDATASETITER_MAGIC;
+ iterator->common.methods = &rdatasetiter_methods;
+ iterator->common.db = db;
+ iterator->common.node = NULL;
+ attachnode(db, node, &iterator->common.node);
+ iterator->common.version = version;
+ iterator->common.options = options;
+ iterator->common.now = now;
+
+ *iteratorp = (dns_rdatasetiter_t *)iterator;
+
+ return (ISC_R_SUCCESS);
+}
+
+static dns_dbmethods_t ecdb_methods = {
+ attach,
+ detach,
+ NULL, /* beginload */
+ NULL, /* endload */
+ NULL, /* serialize */
+ NULL, /* dump */
+ NULL, /* currentversion */
+ NULL, /* newversion */
+ NULL, /* attachversion */
+ NULL, /* closeversion */
+ findnode,
+ find,
+ findzonecut,
+ attachnode,
+ detachnode,
+ NULL, /* expirenode */
+ NULL, /* printnode */
+ createiterator, /* createiterator */
+ NULL, /* findrdataset */
+ allrdatasets,
+ addrdataset,
+ NULL, /* subtractrdataset */
+ deleterdataset,
+ NULL, /* issecure */
+ NULL, /* nodecount */
+ NULL, /* ispersistent */
+ NULL, /* overmem */
+ NULL, /* settask */
+ NULL, /* getoriginnode */
+ NULL, /* transfernode */
+ NULL, /* getnsec3parameters */
+ NULL, /* findnsec3node */
+ NULL, /* setsigningtime */
+ NULL, /* getsigningtime */
+ NULL, /* resigned */
+ NULL, /* isdnssec */
+ NULL, /* getrrsetstats */
+ NULL, /* rpz_attach */
+ NULL, /* rpz_ready */
+ NULL, /* findnodeext */
+ NULL, /* findext */
+ NULL, /* setcachestats */
+ NULL, /* hashsize */
+ NULL, /* nodefullname */
+ NULL, /* getsize */
+ NULL, /* setservestalettl */
+ NULL, /* getservestalettl */
+ NULL /* setgluecachestats */
+};
+
+static isc_result_t
+dns_ecdb_create(isc_mem_t *mctx, const dns_name_t *origin, dns_dbtype_t type,
+ dns_rdataclass_t rdclass, unsigned int argc, char *argv[],
+ void *driverarg, dns_db_t **dbp) {
+ dns_ecdb_t *ecdb;
+ isc_result_t result;
+
+ REQUIRE(mctx != NULL);
+ REQUIRE(origin == dns_rootname);
+ REQUIRE(type == dns_dbtype_cache);
+ REQUIRE(dbp != NULL && *dbp == NULL);
+
+ UNUSED(argc);
+ UNUSED(argv);
+ UNUSED(driverarg);
+
+ ecdb = isc_mem_get(mctx, sizeof(*ecdb));
+
+ ecdb->common.attributes = DNS_DBATTR_CACHE;
+ ecdb->common.rdclass = rdclass;
+ ecdb->common.methods = &ecdb_methods;
+ dns_name_init(&ecdb->common.origin, NULL);
+ result = dns_name_dupwithoffsets(origin, mctx, &ecdb->common.origin);
+ if (result != ISC_R_SUCCESS) {
+ isc_mem_put(mctx, ecdb, sizeof(*ecdb));
+ return (result);
+ }
+
+ isc_mutex_init(&ecdb->lock);
+
+ isc_refcount_init(&ecdb->references, 1);
+ ISC_LIST_INIT(ecdb->nodes);
+
+ ecdb->common.mctx = NULL;
+ isc_mem_attach(mctx, &ecdb->common.mctx);
+ ecdb->common.impmagic = ECDB_MAGIC;
+ ecdb->common.magic = DNS_DB_MAGIC;
+
+ *dbp = (dns_db_t *)ecdb;
+
+ return (ISC_R_SUCCESS);
+}
+
+/*%
+ * Rdataset Methods
+ */
+
+static void
+rdataset_disassociate(dns_rdataset_t *rdataset) {
+ dns_db_t *db = rdataset->private1;
+ dns_dbnode_t *node = rdataset->private2;
+
+ dns_db_detachnode(db, &node);
+}
+
+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);
+ }
+#if DNS_RDATASET_FIXED
+ raw += 2 + (4 * count);
+#else /* if DNS_RDATASET_FIXED */
+ raw += 2;
+#endif /* if DNS_RDATASET_FIXED */
+ /*
+ * 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];
+#if DNS_RDATASET_FIXED
+ raw += length + 4;
+#else /* if DNS_RDATASET_FIXED */
+ raw += length + 2;
+#endif /* if DNS_RDATASET_FIXED */
+ 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;
+ unsigned int length;
+ unsigned int flags = 0;
+
+ REQUIRE(raw != NULL);
+
+ length = raw[0] * 256 + raw[1];
+#if DNS_RDATASET_FIXED
+ raw += 4;
+#else /* if DNS_RDATASET_FIXED */
+ raw += 2;
+#endif /* if DNS_RDATASET_FIXED */
+ if (rdataset->type == dns_rdatatype_rrsig) {
+ if ((*raw & DNS_RDATASLAB_OFFLINE) != 0) {
+ flags |= DNS_RDATA_OFFLINE;
+ }
+ length--;
+ raw++;
+ }
+ r.length = length;
+ r.base = raw;
+ dns_rdata_fromregion(rdata, rdataset->rdclass, rdataset->type, &r);
+ rdata->flags |= flags;
+}
+
+static void
+rdataset_clone(dns_rdataset_t *source, dns_rdataset_t *target) {
+ dns_db_t *db = source->private1;
+ dns_dbnode_t *node = source->private2;
+ dns_dbnode_t *cloned_node = NULL;
+
+ attachnode(db, node, &cloned_node);
+ *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) {
+ rdatasetheader_t *header = rdataset->private3;
+
+ header--;
+ header->trust = rdataset->trust = trust;
+}
+
+/*
+ * Rdataset Iterator Methods
+ */
+
+static void
+rdatasetiter_destroy(dns_rdatasetiter_t **iteratorp) {
+ isc_mem_t *mctx;
+ union {
+ dns_rdatasetiter_t *rdatasetiterator;
+ ecdb_rdatasetiter_t *ecdbiterator;
+ } u;
+
+ REQUIRE(iteratorp != NULL);
+ REQUIRE(DNS_RDATASETITER_VALID(*iteratorp));
+
+ u.rdatasetiterator = *iteratorp;
+ *iteratorp = NULL;
+
+ mctx = u.ecdbiterator->common.db->mctx;
+ u.ecdbiterator->common.magic = 0;
+
+ dns_db_detachnode(u.ecdbiterator->common.db,
+ &u.ecdbiterator->common.node);
+ isc_mem_put(mctx, u.ecdbiterator, sizeof(ecdb_rdatasetiter_t));
+}
+
+static isc_result_t
+rdatasetiter_first(dns_rdatasetiter_t *iterator) {
+ REQUIRE(DNS_RDATASETITER_VALID(iterator));
+
+ ecdb_rdatasetiter_t *ecdbiterator = (ecdb_rdatasetiter_t *)iterator;
+ dns_ecdbnode_t *ecdbnode = (dns_ecdbnode_t *)iterator->node;
+
+ if (ISC_LIST_EMPTY(ecdbnode->rdatasets)) {
+ return (ISC_R_NOMORE);
+ }
+ ecdbiterator->current = ISC_LIST_HEAD(ecdbnode->rdatasets);
+ return (ISC_R_SUCCESS);
+}
+
+static isc_result_t
+rdatasetiter_next(dns_rdatasetiter_t *iterator) {
+ REQUIRE(DNS_RDATASETITER_VALID(iterator));
+
+ ecdb_rdatasetiter_t *ecdbiterator = (ecdb_rdatasetiter_t *)iterator;
+
+ ecdbiterator->current = ISC_LIST_NEXT(ecdbiterator->current, link);
+ if (ecdbiterator->current == NULL) {
+ return (ISC_R_NOMORE);
+ } else {
+ return (ISC_R_SUCCESS);
+ }
+}
+
+static void
+rdatasetiter_current(dns_rdatasetiter_t *iterator, dns_rdataset_t *rdataset) {
+ ecdb_rdatasetiter_t *ecdbiterator = (ecdb_rdatasetiter_t *)iterator;
+ dns_ecdb_t *ecdb;
+
+ ecdb = (dns_ecdb_t *)iterator->db;
+ REQUIRE(VALID_ECDB(ecdb));
+
+ bind_rdataset(ecdb, iterator->node, ecdbiterator->current, rdataset);
+}