/src/bind9/lib/dns/catz.c

Source
/*
 * 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 <stdint.h>
#include <stdlib.h>
#include <unistd.h>

#include <isc/async.h>
#include <isc/hex.h>
#include <isc/loop.h>
#include <isc/md.h>
#include <isc/mem.h>
#include <isc/parseint.h>
#include <isc/result.h>
#include <isc/util.h>
#include <isc/work.h>

#include <dns/catz.h>
#include <dns/dbiterator.h>
#include <dns/name.h>
#include <dns/rdatasetiter.h>
#include <dns/view.h>
#include <dns/zone.h>

#define DNS_CATZ_ZONE_MAGIC  ISC_MAGIC('c', 'a', 't', 'z')
#define DNS_CATZ_ZONES_MAGIC ISC_MAGIC('c', 'a', 't', 's')
#define DNS_CATZ_ENTRY_MAGIC ISC_MAGIC('c', 'a', 't', 'e')
#define DNS_CATZ_COO_MAGIC   ISC_MAGIC('c', 'a', 't', 'c')

#define DNS_CATZ_ZONE_VALID(catz)   ISC_MAGIC_VALID(catz, DNS_CATZ_ZONE_MAGIC)
#define DNS_CATZ_ZONES_VALID(catzs) ISC_MAGIC_VALID(catzs, DNS_CATZ_ZONES_MAGIC)
#define DNS_CATZ_ENTRY_VALID(entry) ISC_MAGIC_VALID(entry, DNS_CATZ_ENTRY_MAGIC)
#define DNS_CATZ_COO_VALID(coo)     ISC_MAGIC_VALID(coo, DNS_CATZ_COO_MAGIC)

#define DNS_CATZ_VERSION_UNDEFINED ((uint32_t)(-1))

/*%
 * Change of ownership permissions
 */
struct dns_catz_coo {
  unsigned int magic;
  dns_name_t name;
  isc_refcount_t references;
};

typedef struct coos {
  isc_mutex_t lock;
  isc_mem_t *mctx;
  isc_ht_t *inner;
} coos_t;

/*%
 * Single member zone in a catalog
 */
struct dns_catz_entry {
  unsigned int magic;
  dns_name_t name;
  dns_catz_options_t opts;
  isc_refcount_t references;
};

/*%
 * Catalog zone
 */
struct dns_catz_zone {
  unsigned int magic;
  isc_loop_t *loop;
  dns_name_t name;
  dns_catz_zones_t *catzs;
  dns_rdata_t soa;
  uint32_t version;
  /* key in entries is 'mhash', not domain name! */
  isc_ht_t *entries;
  /* key in coos is domain name */
  coos_t coos;

  /*
   * defoptions are taken from named.conf
   * zoneoptions are global options from zone
   */
  dns_catz_options_t defoptions;
  dns_catz_options_t zoneoptions;
  isc_time_t lastupdated;

  bool updatepending;       /* there is an update pending */
  bool updaterunning;       /* there is an update running */
  dns_db_t *db;         /* zones database */
  dns_dbversion_t *dbversion;   /* version we will be updating to */
  dns_db_t *updb;         /* zones database we're working on */
  dns_dbversion_t *updbversion; /* version we're working on */

  isc_timer_t *updatetimer;

  bool active;
  bool broken;

  isc_refcount_t references;
  isc_mutex_t lock;
};

static void
dns__catz_timer_cb(void *);
static void
dns__catz_timer_start(dns_catz_zone_t *catz);
static void
dns__catz_timer_stop(void *arg);

static isc_result_t
dns__catz_update_cb(void *data);
static void
dns__catz_done_cb(void *data, isc_result_t result);

static isc_result_t
catz_process_zones_entry(dns_catz_zone_t *catz, dns_rdataset_t *value,
       dns_label_t *mhash);
static isc_result_t
catz_process_zones_suboption(dns_catz_zone_t *catz, dns_rdataset_t *value,
           dns_label_t *mhash, dns_name_t *name);
static void
catz_entry_add_or_mod(dns_catz_zone_t *catz, isc_ht_t *ht, unsigned char *key,
          size_t keysize, dns_catz_entry_t *nentry,
          dns_catz_entry_t *oentry, const char *msg,
          const char *zname, const char *czname);

/*%
 * Collection of catalog zones for a view
 */
struct dns_catz_zones {
  unsigned int magic;
  isc_ht_t *zones;
  isc_mem_t *mctx;
  isc_refcount_t references;
  isc_mutex_t lock;
  dns_catz_zonemodmethods_t *zmm;
  dns_view_t *view;
  atomic_bool shuttingdown;
};

void
dns_catz_options_init(dns_catz_options_t *options) {
  REQUIRE(options != NULL);

  dns_ipkeylist_init(&options->masters);

  options->allow_query = NULL;
  options->allow_transfer = NULL;

  options->allow_query = NULL;
  options->allow_transfer = NULL;

  options->in_memory = false;
  options->min_update_interval = 5;
  options->zonedir = NULL;
}

void
dns_catz_options_free(dns_catz_options_t *options, isc_mem_t *mctx) {
  REQUIRE(options != NULL);
  REQUIRE(mctx != NULL);

  if (options->masters.count != 0) {
    dns_ipkeylist_clear(mctx, &options->masters);
  }
  if (options->zonedir != NULL) {
    isc_mem_free(mctx, options->zonedir);
  }
  if (options->allow_query != NULL) {
    isc_buffer_free(&options->allow_query);
  }
  if (options->allow_transfer != NULL) {
    isc_buffer_free(&options->allow_transfer);
  }
}

void
dns_catz_options_copy(isc_mem_t *mctx, const dns_catz_options_t *src,
          dns_catz_options_t *dst) {
  REQUIRE(mctx != NULL);
  REQUIRE(src != NULL);
  REQUIRE(dst != NULL);
  REQUIRE(dst->masters.count == 0);
  REQUIRE(dst->allow_query == NULL);
  REQUIRE(dst->allow_transfer == NULL);

  if (src->masters.count != 0) {
    dns_ipkeylist_copy(mctx, &src->masters, &dst->masters);
  }

  if (dst->zonedir != NULL) {
    isc_mem_free(mctx, dst->zonedir);
  }

  if (src->zonedir != NULL) {
    dst->zonedir = isc_mem_strdup(mctx, src->zonedir);
  }

  if (src->allow_query != NULL) {
    isc_buffer_dup(mctx, &dst->allow_query, src->allow_query);
  }

  if (src->allow_transfer != NULL) {
    isc_buffer_dup(mctx, &dst->allow_transfer, src->allow_transfer);
  }
}

void
dns_catz_options_setdefault(isc_mem_t *mctx, const dns_catz_options_t *defaults,
          dns_catz_options_t *opts) {
  REQUIRE(mctx != NULL);
  REQUIRE(defaults != NULL);
  REQUIRE(opts != NULL);

  if (opts->masters.count == 0 && defaults->masters.count != 0) {
    dns_ipkeylist_copy(mctx, &defaults->masters, &opts->masters);
  }

  if (defaults->zonedir != NULL) {
    if (opts->zonedir != NULL) {
      isc_mem_free(mctx, opts->zonedir);
    }
    opts->zonedir = isc_mem_strdup(mctx, defaults->zonedir);
  }

  if (opts->allow_query == NULL && defaults->allow_query != NULL) {
    isc_buffer_dup(mctx, &opts->allow_query, defaults->allow_query);
  }
  if (opts->allow_transfer == NULL && defaults->allow_transfer != NULL) {
    isc_buffer_dup(mctx, &opts->allow_transfer,
             defaults->allow_transfer);
  }

  /* This option is always taken from config, so it's always 'default' */
  opts->in_memory = defaults->in_memory;
}

static dns_catz_coo_t *
catz_coo_new(isc_mem_t *mctx, const dns_name_t *domain) {
  REQUIRE(mctx != NULL);
  REQUIRE(domain != NULL);

  dns_catz_coo_t *ncoo = isc_mem_get(mctx, sizeof(*ncoo));
  *ncoo = (dns_catz_coo_t){
    .magic = DNS_CATZ_COO_MAGIC,
  };
  dns_name_init(&ncoo->name);
  dns_name_dup(domain, mctx, &ncoo->name);
  isc_refcount_init(&ncoo->references, 1);

  return ncoo;
}

static void
catz_coo_detach(isc_mem_t *mctx, dns_catz_coo_t **coop) {
  dns_catz_coo_t *coo;

  REQUIRE(mctx != NULL);
  REQUIRE(coop != NULL && DNS_CATZ_COO_VALID(*coop));
  coo = *coop;
  *coop = NULL;

  if (isc_refcount_decrement(&coo->references) == 1) {
    coo->magic = 0;
    isc_refcount_destroy(&coo->references);
    if (dns_name_dynamic(&coo->name)) {
      dns_name_free(&coo->name, mctx);
    }
    isc_mem_put(mctx, coo, sizeof(*coo));
  }
}

static void
coos_init(coos_t *coos, isc_mem_t *mctx) {
  REQUIRE(coos != NULL);
  REQUIRE(mctx != NULL);

  isc_mutex_init(&coos->lock);
  isc_mem_attach(mctx, &coos->mctx);
  isc_ht_init(&coos->inner, coos->mctx, 4, ISC_HT_CASE_INSENSITIVE);
}

static isc_ht_t *
coos_replace(coos_t *coos, isc_ht_t *newinner) {
  isc_ht_t *oldinner = NULL;

  REQUIRE(coos != NULL);
  REQUIRE(coos->mctx != NULL);

  LOCK(&coos->lock);
  oldinner = coos->inner;
  coos->inner = newinner;
  UNLOCK(&coos->lock);

  return oldinner;
}

static isc_ht_t *
coos_take(coos_t *coos) {
  return coos_replace(coos, NULL);
}

static void
coos_destroy_table(coos_t *coos, isc_ht_t **innerp) {
  isc_ht_iter_t *iter = NULL;
  isc_ht_t *inner = NULL;
  isc_result_t result;

  REQUIRE(coos != NULL);
  REQUIRE(coos->mctx != NULL);
  REQUIRE(innerp != NULL);

  inner = *innerp;
  if (inner == NULL) {
    return;
  }

  isc_ht_iter_create(inner, &iter);
  for (result = isc_ht_iter_first(iter); result == ISC_R_SUCCESS;
       result = isc_ht_iter_delcurrent_next(iter))
  {
    dns_catz_coo_t *coo = NULL;

    isc_ht_iter_current(iter, (void **)&coo);
    catz_coo_detach(coos->mctx, &coo);
  }
  INSIST(result == ISC_R_NOMORE);
  isc_ht_iter_destroy(&iter);

  /* The hashtable has to be empty now. */
  INSIST(isc_ht_count(inner) == 0);
  isc_ht_destroy(innerp);
}

static void
coos_destroy(coos_t *coos) {
  isc_ht_t *inner = NULL;

  REQUIRE(coos != NULL);
  REQUIRE(coos->mctx != NULL);

  inner = coos_take(coos);
  coos_destroy_table(coos, &inner);
  isc_mutex_destroy(&coos->lock);
  isc_mem_detach(&coos->mctx);
}

static void
coos_add(coos_t *coos, dns_catz_entry_t *entry, const dns_name_t *domain) {
  dns_catz_coo_t *coo = NULL;
  isc_result_t result;

  REQUIRE(coos != NULL);
  REQUIRE(coos->mctx != NULL);
  REQUIRE(DNS_CATZ_ENTRY_VALID(entry));
  REQUIRE(domain != NULL);

  LOCK(&coos->lock);
  INSIST(coos->inner != NULL);
  result = isc_ht_find(coos->inner, entry->name.ndata, entry->name.length,
           (void **)&coo);
  if (result != ISC_R_SUCCESS) {
    coo = catz_coo_new(coos->mctx, domain);
    result = isc_ht_add(coos->inner, entry->name.ndata,
            entry->name.length, coo);
  }
  UNLOCK(&coos->lock);

  INSIST(result == ISC_R_SUCCESS);
}

static bool
coos_match(coos_t *coos, const dns_name_t *zone, const dns_name_t *catz) {
  dns_catz_coo_t *coo = NULL;
  bool match = false;

  REQUIRE(coos != NULL);
  REQUIRE(coos->mctx != NULL);
  REQUIRE(zone != NULL);
  REQUIRE(catz != NULL);

  LOCK(&coos->lock);
  if (coos->inner != NULL &&
      isc_ht_find(coos->inner, zone->ndata, zone->length,
      (void **)&coo) == ISC_R_SUCCESS)
  {
    match = dns_name_equal(&coo->name, catz);
  }
  UNLOCK(&coos->lock);

  return match;
}

dns_catz_entry_t *
dns_catz_entry_new(isc_mem_t *mctx, const dns_name_t *domain) {
  REQUIRE(mctx != NULL);

  dns_catz_entry_t *nentry = isc_mem_get(mctx, sizeof(*nentry));
  *nentry = (dns_catz_entry_t){
    .magic = DNS_CATZ_ENTRY_MAGIC,
  };

  dns_name_init(&nentry->name);
  if (domain != NULL) {
    dns_name_dup(domain, mctx, &nentry->name);
  }

  dns_catz_options_init(&nentry->opts);
  isc_refcount_init(&nentry->references, 1);

  return nentry;
}

dns_name_t *
dns_catz_entry_getname(dns_catz_entry_t *entry) {
  REQUIRE(DNS_CATZ_ENTRY_VALID(entry));
  return &entry->name;
}

dns_catz_entry_t *
dns_catz_entry_copy(dns_catz_zone_t *catz, const dns_catz_entry_t *entry) {
  REQUIRE(DNS_CATZ_ZONE_VALID(catz));
  REQUIRE(DNS_CATZ_ENTRY_VALID(entry));

  dns_catz_entry_t *nentry = dns_catz_entry_new(catz->catzs->mctx,
                  &entry->name);

  dns_catz_options_copy(catz->catzs->mctx, &entry->opts, &nentry->opts);

  return nentry;
}

void
dns_catz_entry_attach(dns_catz_entry_t *entry, dns_catz_entry_t **entryp) {
  REQUIRE(DNS_CATZ_ENTRY_VALID(entry));
  REQUIRE(entryp != NULL && *entryp == NULL);

  isc_refcount_increment(&entry->references);
  *entryp = entry;
}

void
dns_catz_entry_detach(dns_catz_zone_t *catz, dns_catz_entry_t **entryp) {
  dns_catz_entry_t *entry;

  REQUIRE(DNS_CATZ_ZONE_VALID(catz));
  REQUIRE(entryp != NULL && DNS_CATZ_ENTRY_VALID(*entryp));
  entry = *entryp;
  *entryp = NULL;

  if (isc_refcount_decrement(&entry->references) == 1) {
    isc_mem_t *mctx = catz->catzs->mctx;
    entry->magic = 0;
    isc_refcount_destroy(&entry->references);
    dns_catz_options_free(&entry->opts, mctx);
    if (dns_name_dynamic(&entry->name)) {
      dns_name_free(&entry->name, mctx);
    }
    isc_mem_put(mctx, entry, sizeof(*entry));
  }
}

bool
dns_catz_entry_validate(const dns_catz_entry_t *entry) {
  REQUIRE(DNS_CATZ_ENTRY_VALID(entry));
  UNUSED(entry);

  return true;
}

bool
dns_catz_entry_cmp(const dns_catz_entry_t *ea, const dns_catz_entry_t *eb) {
  isc_region_t ra, rb;

  REQUIRE(DNS_CATZ_ENTRY_VALID(ea));
  REQUIRE(DNS_CATZ_ENTRY_VALID(eb));

  if (ea == eb) {
    return true;
  }

  if (ea->opts.masters.count != eb->opts.masters.count) {
    return false;
  }

  if (memcmp(ea->opts.masters.addrs, eb->opts.masters.addrs,
       ea->opts.masters.count * sizeof(isc_sockaddr_t)))
  {
    return false;
  }

  for (size_t i = 0; i < eb->opts.masters.count; i++) {
    if ((ea->opts.masters.keys[i] == NULL) !=
        (eb->opts.masters.keys[i] == NULL))
    {
      return false;
    }
    if (ea->opts.masters.keys[i] == NULL) {
      continue;
    }
    if (!dns_name_equal(ea->opts.masters.keys[i],
            eb->opts.masters.keys[i]))
    {
      return false;
    }
  }

  for (size_t i = 0; i < eb->opts.masters.count; i++) {
    if ((ea->opts.masters.tlss[i] == NULL) !=
        (eb->opts.masters.tlss[i] == NULL))
    {
      return false;
    }
    if (ea->opts.masters.tlss[i] == NULL) {
      continue;
    }
    if (!dns_name_equal(ea->opts.masters.tlss[i],
            eb->opts.masters.tlss[i]))
    {
      return false;
    }
  }

  /* If one is NULL and the other isn't, the entries don't match */
  if ((ea->opts.allow_query == NULL) != (eb->opts.allow_query == NULL)) {
    return false;
  }

  /* If one is non-NULL, then they both are */
  if (ea->opts.allow_query != NULL) {
    isc_buffer_usedregion(ea->opts.allow_query, &ra);
    isc_buffer_usedregion(eb->opts.allow_query, &rb);
    if (isc_region_compare(&ra, &rb)) {
      return false;
    }
  }

  /* Repeat the above checks with allow_transfer */
  if ((ea->opts.allow_transfer == NULL) !=
      (eb->opts.allow_transfer == NULL))
  {
    return false;
  }

  if (ea->opts.allow_transfer != NULL) {
    isc_buffer_usedregion(ea->opts.allow_transfer, &ra);
    isc_buffer_usedregion(eb->opts.allow_transfer, &rb);
    if (isc_region_compare(&ra, &rb)) {
      return false;
    }
  }

  return true;
}

dns_name_t *
dns_catz_zone_getname(dns_catz_zone_t *catz) {
  REQUIRE(DNS_CATZ_ZONE_VALID(catz));

  return &catz->name;
}

dns_catz_options_t *
dns_catz_zone_getdefoptions(dns_catz_zone_t *catz) {
  REQUIRE(DNS_CATZ_ZONE_VALID(catz));

  return &catz->defoptions;
}

void
dns_catz_zone_resetdefoptions(dns_catz_zone_t *catz) {
  REQUIRE(DNS_CATZ_ZONE_VALID(catz));

  dns_catz_options_free(&catz->defoptions, catz->catzs->mctx);
  dns_catz_options_init(&catz->defoptions);
}

/*%<
 * Merge 'newcatz' into 'catz', calling addzone/delzone/modzone
 * (from catz->catzs->zmm) for appropriate member zones.
 *
 * Requires:
 * \li  'catz' is a valid dns_catz_zone_t.
 * \li  'newcatz' is a valid dns_catz_zone_t.
 *
 */
static isc_result_t
dns__catz_zones_merge(dns_catz_zone_t *catz, dns_catz_zone_t *newcatz) {
  isc_result_t result;
  isc_ht_iter_t *iter1 = NULL, *iter2 = NULL;
  isc_ht_iter_t *iteradd = NULL, *itermod = NULL;
  isc_ht_t *toadd = NULL, *tomod = NULL;
  bool delcur = false;
  char czname[DNS_NAME_FORMATSIZE];
  char zname[DNS_NAME_FORMATSIZE];
  dns_catz_zoneop_fn_t addzone, modzone, delzone;

  REQUIRE(DNS_CATZ_ZONE_VALID(catz));
  REQUIRE(DNS_CATZ_ZONE_VALID(newcatz));

  LOCK(&catz->lock);

  /* TODO verify the new zone first! */

  addzone = catz->catzs->zmm->addzone;
  modzone = catz->catzs->zmm->modzone;
  delzone = catz->catzs->zmm->delzone;

  /* Copy zoneoptions from newcatz into catz. */

  dns_catz_options_free(&catz->zoneoptions, catz->catzs->mctx);
  dns_catz_options_copy(catz->catzs->mctx, &newcatz->zoneoptions,
            &catz->zoneoptions);
  dns_catz_options_setdefault(catz->catzs->mctx, &catz->defoptions,
            &catz->zoneoptions);

  dns_name_format(&catz->name, czname, DNS_NAME_FORMATSIZE);

  isc_ht_init(&toadd, catz->catzs->mctx, 1, ISC_HT_CASE_INSENSITIVE);
  isc_ht_init(&tomod, catz->catzs->mctx, 1, ISC_HT_CASE_INSENSITIVE);
  isc_ht_iter_create(newcatz->entries, &iter1);
  isc_ht_iter_create(catz->entries, &iter2);

  /*
   * We can create those iterators now, even though toadd and tomod are
   * empty
   */
  isc_ht_iter_create(toadd, &iteradd);
  isc_ht_iter_create(tomod, &itermod);

  /*
   * First - walk the new zone and find all nodes that are not in the
   * old zone, or are in both zones and are modified.
   */
  for (result = isc_ht_iter_first(iter1); result == ISC_R_SUCCESS;
       result = delcur ? isc_ht_iter_delcurrent_next(iter1)
           : isc_ht_iter_next(iter1))
  {
    isc_result_t find_result;
    dns_catz_zone_t *parentcatz = NULL;
    dns_catz_entry_t *nentry = NULL;
    dns_catz_entry_t *oentry = NULL;
    dns_zone_t *zone = NULL;
    unsigned char *key = NULL;
    size_t keysize;
    delcur = false;

    isc_ht_iter_current(iter1, (void **)&nentry);
    isc_ht_iter_currentkey(iter1, &key, &keysize);

    /*
     * Spurious record that came from suboption without main
     * record, removed.
     * xxxwpk: make it a separate verification phase?
     */
    if (nentry->name.length == 0) {
      dns_catz_entry_detach(newcatz, &nentry);
      delcur = true;
      continue;
    }

    dns_name_format(&nentry->name, zname, DNS_NAME_FORMATSIZE);

    isc_log_write(DNS_LOGCATEGORY_GENERAL, DNS_LOGMODULE_CATZ,
            ISC_LOG_DEBUG(3),
            "catz: iterating over '%s' from catalog '%s'",
            zname, czname);
    dns_catz_options_setdefault(catz->catzs->mctx,
              &catz->zoneoptions, &nentry->opts);

    /* Try to find the zone in the view */
    find_result = dns_view_findzone(catz->catzs->view,
            dns_catz_entry_getname(nentry),
            DNS_ZTFIND_EXACT, &zone);
    if (find_result == ISC_R_SUCCESS) {
      char pczname[DNS_NAME_FORMATSIZE];
      bool coo_match = false;

      /*
       * Change of ownership (coo) processing, if required
       */
      parentcatz = dns_zone_get_parentcatz(zone);
      if (parentcatz != NULL && parentcatz != catz) {
        coo_match = coos_match(&parentcatz->coos,
                   &nentry->name,
                   &catz->name);
      }
      if (coo_match) {
        dns_name_format(&parentcatz->name, pczname,
            DNS_NAME_FORMATSIZE);
        isc_log_write(DNS_LOGCATEGORY_GENERAL,
                DNS_LOGMODULE_CATZ,
                ISC_LOG_DEBUG(3),
                "catz: zone '%s' "
                "change of ownership from "
                "'%s' to '%s'",
                zname, pczname, czname);
        result = delzone(nentry, parentcatz,
             parentcatz->catzs->view,
             parentcatz->catzs->zmm->udata);
        isc_log_write(DNS_LOGCATEGORY_GENERAL,
                DNS_LOGMODULE_CATZ, ISC_LOG_INFO,
                "catz: deleting zone '%s' "
                "from catalog '%s' - %s",
                zname, pczname,
                isc_result_totext(result));
      }
      dns_zone_detach(&zone);
    }

    /* Try to find the zone in the old catalog zone */
    result = isc_ht_find(catz->entries, key, (uint32_t)keysize,
             (void **)&oentry);
    if (result != ISC_R_SUCCESS) {
      if (find_result == ISC_R_SUCCESS && parentcatz == catz)
      {
        /*
         * This means that the zone's unique label
         * has been changed, in that case we must
         * reset the zone's internal state by removing
         * and re-adding it.
         *
         * Scheduling the addition now, the removal will
         * be scheduled below, when walking the old
         * zone for remaining entries, and then we will
         * perform deletions earlier than additions and
         * modifications.
         */
        isc_log_write(DNS_LOGCATEGORY_GENERAL,
                DNS_LOGMODULE_CATZ, ISC_LOG_INFO,
                "catz: zone '%s' unique label "
                "has changed, reset state",
                zname);
      }

      catz_entry_add_or_mod(catz, toadd, key, keysize, nentry,
                NULL, "adding", zname, czname);
      continue;
    }

    if (find_result != ISC_R_SUCCESS) {
      isc_log_write(DNS_LOGCATEGORY_GENERAL,
              DNS_LOGMODULE_CATZ, ISC_LOG_DEBUG(3),
              "catz: zone '%s' was expected to exist "
              "but can not be found, will be restored",
              zname);
      catz_entry_add_or_mod(catz, toadd, key, keysize, nentry,
                oentry, "adding", zname, czname);
      continue;
    }

    if (dns_catz_entry_cmp(oentry, nentry) != true) {
      catz_entry_add_or_mod(catz, tomod, key, keysize, nentry,
                oentry, "modifying", zname,
                czname);
      continue;
    }

    /*
     * Delete the old entry so that it won't accidentally be
     * removed as a non-existing entry below.
     */
    dns_catz_entry_detach(catz, &oentry);
    result = isc_ht_delete(catz->entries, key, (uint32_t)keysize);
    RUNTIME_CHECK(result == ISC_R_SUCCESS);
  }
  RUNTIME_CHECK(result == ISC_R_NOMORE);
  isc_ht_iter_destroy(&iter1);

  /*
   * Then - walk the old zone; only deleted entries should remain.
   */
  for (result = isc_ht_iter_first(iter2); result == ISC_R_SUCCESS;
       result = isc_ht_iter_delcurrent_next(iter2))
  {
    dns_catz_entry_t *entry = NULL;
    isc_ht_iter_current(iter2, (void **)&entry);

    dns_name_format(&entry->name, zname, DNS_NAME_FORMATSIZE);
    result = delzone(entry, catz, catz->catzs->view,
         catz->catzs->zmm->udata);
    isc_log_write(DNS_LOGCATEGORY_GENERAL, DNS_LOGMODULE_CATZ,
            ISC_LOG_INFO,
            "catz: deleting zone '%s' from catalog '%s' - %s",
            zname, czname, isc_result_totext(result));
    dns_catz_entry_detach(catz, &entry);
  }
  RUNTIME_CHECK(result == ISC_R_NOMORE);
  isc_ht_iter_destroy(&iter2);
  /* At this moment catz->entries has to be empty. */
  INSIST(isc_ht_count(catz->entries) == 0);
  isc_ht_destroy(&catz->entries);

  for (result = isc_ht_iter_first(iteradd); result == ISC_R_SUCCESS;
       result = isc_ht_iter_delcurrent_next(iteradd))
  {
    dns_catz_entry_t *entry = NULL;
    isc_ht_iter_current(iteradd, (void **)&entry);

    dns_name_format(&entry->name, zname, DNS_NAME_FORMATSIZE);
    result = addzone(entry, catz, catz->catzs->view,
         catz->catzs->zmm->udata);
    isc_log_write(DNS_LOGCATEGORY_GENERAL, DNS_LOGMODULE_CATZ,
            ISC_LOG_INFO,
            "catz: adding zone '%s' from catalog "
            "'%s' - %s",
            zname, czname, isc_result_totext(result));
  }

  for (result = isc_ht_iter_first(itermod); result == ISC_R_SUCCESS;
       result = isc_ht_iter_delcurrent_next(itermod))
  {
    dns_catz_entry_t *entry = NULL;
    isc_ht_iter_current(itermod, (void **)&entry);

    dns_name_format(&entry->name, zname, DNS_NAME_FORMATSIZE);
    result = modzone(entry, catz, catz->catzs->view,
         catz->catzs->zmm->udata);
    isc_log_write(DNS_LOGCATEGORY_GENERAL, DNS_LOGMODULE_CATZ,
            ISC_LOG_INFO,
            "catz: modifying zone '%s' from catalog "
            "'%s' - %s",
            zname, czname, isc_result_totext(result));
  }

  catz->entries = newcatz->entries;
  newcatz->entries = NULL;

  /*
   * We do not need to merge old coo (change of ownership) permission
   * records with the new ones, just replace them.
   */
  isc_ht_t *newcoos = coos_take(&newcatz->coos);
  isc_ht_t *oldcoos = coos_replace(&catz->coos, newcoos);
  coos_destroy_table(&catz->coos, &oldcoos);

  result = ISC_R_SUCCESS;

  isc_ht_iter_destroy(&iteradd);
  isc_ht_iter_destroy(&itermod);
  isc_ht_destroy(&toadd);
  isc_ht_destroy(&tomod);

  UNLOCK(&catz->lock);

  return result;
}

dns_catz_zones_t *
dns_catz_zones_new(isc_mem_t *mctx, dns_catz_zonemodmethods_t *zmm) {
  REQUIRE(mctx != NULL);
  REQUIRE(zmm != NULL);

  dns_catz_zones_t *catzs = isc_mem_get(mctx, sizeof(*catzs));
  *catzs = (dns_catz_zones_t){
    .zmm = zmm,
    .magic = DNS_CATZ_ZONES_MAGIC,
  };

  isc_mutex_init(&catzs->lock);
  isc_refcount_init(&catzs->references, 1);
  isc_ht_init(&catzs->zones, mctx, 4, ISC_HT_CASE_INSENSITIVE);
  isc_mem_attach(mctx, &catzs->mctx);

  return catzs;
}

void *
dns_catz_zones_get_udata(dns_catz_zones_t *catzs) {
  REQUIRE(DNS_CATZ_ZONES_VALID(catzs));

  return catzs->zmm->udata;
}

void
dns_catz_catzs_set_view(dns_catz_zones_t *catzs, dns_view_t *view) {
  REQUIRE(DNS_CATZ_ZONES_VALID(catzs));
  REQUIRE(DNS_VIEW_VALID(view));
  /* Either it's a new one or it's being reconfigured. */
  REQUIRE(catzs->view == NULL || !strcmp(catzs->view->name, view->name));

  if (catzs->view == NULL) {
    dns_view_weakattach(view, &catzs->view);
  } else if (catzs->view != view) {
    dns_view_weakdetach(&catzs->view);
    dns_view_weakattach(view, &catzs->view);
  }
}

dns_catz_zone_t *
dns_catz_zone_new(dns_catz_zones_t *catzs, const dns_name_t *name) {
  REQUIRE(DNS_CATZ_ZONES_VALID(catzs));
  REQUIRE(ISC_MAGIC_VALID(name, DNS_NAME_MAGIC));

  dns_catz_zone_t *catz = isc_mem_get(catzs->mctx, sizeof(*catz));
  *catz = (dns_catz_zone_t){ .active = true,
           .version = DNS_CATZ_VERSION_UNDEFINED,
           .magic = DNS_CATZ_ZONE_MAGIC };

  dns_catz_zones_attach(catzs, &catz->catzs);
  isc_mutex_init(&catz->lock);
  isc_refcount_init(&catz->references, 1);
  isc_ht_init(&catz->entries, catzs->mctx, 4, ISC_HT_CASE_INSENSITIVE);
  coos_init(&catz->coos, catzs->mctx);
  isc_time_settoepoch(&catz->lastupdated);
  dns_catz_options_init(&catz->defoptions);
  dns_catz_options_init(&catz->zoneoptions);
  dns_name_init(&catz->name);
  dns_name_dup(name, catzs->mctx, &catz->name);

  return catz;
}

static void
dns__catz_timer_start(dns_catz_zone_t *catz) {
  uint64_t tdiff;
  isc_interval_t interval;
  isc_time_t now;

  REQUIRE(DNS_CATZ_ZONE_VALID(catz));

  now = isc_time_now();
  tdiff = isc_time_microdiff(&now, &catz->lastupdated) / 1000000;
  if (tdiff < catz->defoptions.min_update_interval) {
    uint64_t defer = catz->defoptions.min_update_interval - tdiff;
    char dname[DNS_NAME_FORMATSIZE];

    dns_name_format(&catz->name, dname, DNS_NAME_FORMATSIZE);
    isc_log_write(DNS_LOGCATEGORY_GENERAL, DNS_LOGMODULE_CATZ,
            ISC_LOG_INFO,
            "catz: %s: new zone version came "
            "too soon, deferring update for "
            "%" PRIu64 " seconds",
            dname, defer);
    isc_interval_set(&interval, (unsigned int)defer, 0);
  } else {
    isc_interval_set(&interval, 0, 0);
  }

  catz->loop = isc_loop();

  isc_timer_create(catz->loop, dns__catz_timer_cb, catz,
       &catz->updatetimer);
  isc_timer_start(catz->updatetimer, isc_timertype_once, &interval);
}

static void
dns__catz_timer_stop(void *arg) {
  dns_catz_zone_t *catz = arg;
  REQUIRE(DNS_CATZ_ZONE_VALID(catz));

  isc_timer_stop(catz->updatetimer);
  isc_timer_destroy(&catz->updatetimer);
  catz->loop = NULL;

  dns_catz_zone_detach(&catz);
}

isc_result_t
dns_catz_zone_add(dns_catz_zones_t *catzs, const dns_name_t *name,
      dns_catz_zone_t **catzp) {
  REQUIRE(DNS_CATZ_ZONES_VALID(catzs));
  REQUIRE(ISC_MAGIC_VALID(name, DNS_NAME_MAGIC));
  REQUIRE(catzp != NULL && *catzp == NULL);

  dns_catz_zone_t *catz = NULL;
  isc_result_t result;
  char zname[DNS_NAME_FORMATSIZE];

  dns_name_format(name, zname, DNS_NAME_FORMATSIZE);
  isc_log_write(DNS_LOGCATEGORY_GENERAL, DNS_LOGMODULE_CATZ,
          ISC_LOG_DEBUG(3), "catz: dns_catz_zone_add %s", zname);

  LOCK(&catzs->lock);

  /*
   * This function is called only during a (re)configuration, while
   * 'catzs->zones' can become NULL only during shutdown.
   */
  INSIST(catzs->zones != NULL);
  INSIST(!atomic_load(&catzs->shuttingdown));

  result = isc_ht_find(catzs->zones, name->ndata, name->length,
           (void **)&catz);
  switch (result) {
  case ISC_R_SUCCESS:
    INSIST(!catz->active);
    catz->active = true;
    result = ISC_R_EXISTS;
    break;
  case ISC_R_NOTFOUND:
    catz = dns_catz_zone_new(catzs, name);

    result = isc_ht_add(catzs->zones, catz->name.ndata,
            catz->name.length, catz);
    INSIST(result == ISC_R_SUCCESS);
    break;
  default:
    UNREACHABLE();
  }

  UNLOCK(&catzs->lock);

  *catzp = catz;

  return result;
}

dns_catz_zone_t *
dns_catz_zone_get(dns_catz_zones_t *catzs, const dns_name_t *name) {
  isc_result_t result;
  dns_catz_zone_t *found = NULL;

  REQUIRE(DNS_CATZ_ZONES_VALID(catzs));
  REQUIRE(ISC_MAGIC_VALID(name, DNS_NAME_MAGIC));

  LOCK(&catzs->lock);
  if (catzs->zones == NULL) {
    UNLOCK(&catzs->lock);
    return NULL;
  }
  result = isc_ht_find(catzs->zones, name->ndata, name->length,
           (void **)&found);
  UNLOCK(&catzs->lock);
  if (result != ISC_R_SUCCESS) {
    return NULL;
  }

  return found;
}

static void
dns__catz_zone_shutdown(dns_catz_zone_t *catz) {
  /* lock must be locked */
  if (catz->updatetimer != NULL) {
    /* Don't wait for timer to trigger for shutdown */
    INSIST(catz->loop != NULL);

    isc_async_run(catz->loop, dns__catz_timer_stop, catz);
  } else {
    dns_catz_zone_detach(&catz);
  }
}

static void
dns__catz_zone_destroy(dns_catz_zone_t *catz) {
  isc_mem_t *mctx = catz->catzs->mctx;

  if (catz->entries != NULL) {
    isc_ht_iter_t *iter = NULL;
    isc_result_t result;
    isc_ht_iter_create(catz->entries, &iter);
    for (result = isc_ht_iter_first(iter); result == ISC_R_SUCCESS;
         result = isc_ht_iter_delcurrent_next(iter))
    {
      dns_catz_entry_t *entry = NULL;

      isc_ht_iter_current(iter, (void **)&entry);
      dns_catz_entry_detach(catz, &entry);
    }
    INSIST(result == ISC_R_NOMORE);
    isc_ht_iter_destroy(&iter);

    /* The hashtable has to be empty now. */
    INSIST(isc_ht_count(catz->entries) == 0);
    isc_ht_destroy(&catz->entries);
  }
  coos_destroy(&catz->coos);
  catz->magic = 0;
  isc_mutex_destroy(&catz->lock);

  if (catz->updatetimer != NULL) {
    isc_timer_async_destroy(&catz->updatetimer);
  }

  if (catz->db != NULL) {
    if (catz->dbversion != NULL) {
      dns_db_closeversion(catz->db, &catz->dbversion, false);
    }
    dns_db_updatenotify_unregister(
      catz->db, dns_catz_dbupdate_callback, catz->catzs);
    dns_db_detach(&catz->db);
  }

  INSIST(!catz->updaterunning);

  dns_name_free(&catz->name, mctx);
  dns_catz_options_free(&catz->defoptions, mctx);
  dns_catz_options_free(&catz->zoneoptions, mctx);

  dns_catz_zones_detach(&catz->catzs);

  isc_mem_put(mctx, catz, sizeof(*catz));
}

static void
dns__catz_zones_destroy(dns_catz_zones_t *catzs) {
  REQUIRE(atomic_load(&catzs->shuttingdown));
  REQUIRE(catzs->zones == NULL);

  catzs->magic = 0;
  isc_mutex_destroy(&catzs->lock);
  if (catzs->view != NULL) {
    dns_view_weakdetach(&catzs->view);
  }
  isc_mem_putanddetach(&catzs->mctx, catzs, sizeof(*catzs));
}

void
dns_catz_zones_shutdown(dns_catz_zones_t *catzs) {
  REQUIRE(DNS_CATZ_ZONES_VALID(catzs));

  if (!atomic_compare_exchange_strong(&catzs->shuttingdown,
              &(bool){ false }, true))
  {
    return;
  }

  LOCK(&catzs->lock);
  if (catzs->zones != NULL) {
    isc_ht_iter_t *iter = NULL;
    isc_result_t result;
    isc_ht_iter_create(catzs->zones, &iter);
    for (result = isc_ht_iter_first(iter); result == ISC_R_SUCCESS;)
    {
      dns_catz_zone_t *catz = NULL;
      isc_ht_iter_current(iter, (void **)&catz);
      result = isc_ht_iter_delcurrent_next(iter);
      dns__catz_zone_shutdown(catz);
    }
    INSIST(result == ISC_R_NOMORE);
    isc_ht_iter_destroy(&iter);
    INSIST(isc_ht_count(catzs->zones) == 0);
    isc_ht_destroy(&catzs->zones);
  }
  UNLOCK(&catzs->lock);
}

#ifdef DNS_CATZ_TRACE
ISC_REFCOUNT_TRACE_IMPL(dns_catz_zone, dns__catz_zone_destroy);
ISC_REFCOUNT_TRACE_IMPL(dns_catz_zones, dns__catz_zones_destroy);
#else
ISC_REFCOUNT_IMPL(dns_catz_zone, dns__catz_zone_destroy);
ISC_REFCOUNT_IMPL(dns_catz_zones, dns__catz_zones_destroy);
#endif

typedef enum {
  CATZ_OPT_NONE,
  CATZ_OPT_ZONES,
  CATZ_OPT_COO,
  CATZ_OPT_VERSION,
  CATZ_OPT_CUSTOM_START, /* CATZ custom properties must go below this */
  CATZ_OPT_EXT,
  CATZ_OPT_PRIMARIES,
  CATZ_OPT_ALLOW_QUERY,
  CATZ_OPT_ALLOW_TRANSFER,
} catz_opt_t;

static bool
catz_opt_cmp(const dns_label_t *option, const char *opt) {
  size_t len = strlen(opt);

  if (option->length - 1 == len &&
      memcmp(opt, option->base + 1, len) == 0)
  {
    return true;
  } else {
    return false;
  }
}

static catz_opt_t
catz_get_option(const dns_label_t *option) {
  if (catz_opt_cmp(option, "ext")) {
    return CATZ_OPT_EXT;
  } else if (catz_opt_cmp(option, "zones")) {
    return CATZ_OPT_ZONES;
  } else if (catz_opt_cmp(option, "masters") ||
       catz_opt_cmp(option, "primaries"))
  {
    return CATZ_OPT_PRIMARIES;
  } else if (catz_opt_cmp(option, "allow-query")) {
    return CATZ_OPT_ALLOW_QUERY;
  } else if (catz_opt_cmp(option, "allow-transfer")) {
    return CATZ_OPT_ALLOW_TRANSFER;
  } else if (catz_opt_cmp(option, "coo")) {
    return CATZ_OPT_COO;
  } else if (catz_opt_cmp(option, "version")) {
    return CATZ_OPT_VERSION;
  } else {
    return CATZ_OPT_NONE;
  }
}

static isc_result_t
catz_process_zones(dns_catz_zone_t *catz, dns_rdataset_t *value,
       dns_name_t *name) {
  dns_label_t mhash;
  dns_name_t opt;

  REQUIRE(DNS_CATZ_ZONE_VALID(catz));
  REQUIRE(DNS_RDATASET_VALID(value));
  REQUIRE(ISC_MAGIC_VALID(name, DNS_NAME_MAGIC));

  uint8_t labels = dns_name_countlabels(name);

  if (labels == 0) {
    return ISC_R_FAILURE;
  }

  dns_name_getlabel(name, labels - 1, &mhash);

  if (labels == 1) {
    return catz_process_zones_entry(catz, value, &mhash);
  } else {
    dns_name_init(&opt);
    dns_name_split(name, 1, &opt, NULL);
    return catz_process_zones_suboption(catz, value, &mhash, &opt);
  }
}

static isc_result_t
catz_process_coo(dns_catz_zone_t *catz, dns_label_t *mhash,
     dns_rdataset_t *value) {
  isc_result_t result;
  dns_rdata_t rdata;
  dns_rdata_ptr_t ptr;
  dns_catz_entry_t *entry = NULL;

  REQUIRE(DNS_CATZ_ZONE_VALID(catz));
  REQUIRE(mhash != NULL);
  REQUIRE(DNS_RDATASET_VALID(value));

  /* Change of Ownership was introduced in version "2" of the schema. */
  if (catz->version < 2) {
    return ISC_R_FAILURE;
  }

  if (value->type != dns_rdatatype_ptr) {
    return ISC_R_FAILURE;
  }

  if (dns_rdataset_count(value) != 1) {
    isc_log_write(DNS_LOGCATEGORY_GENERAL, DNS_LOGMODULE_CATZ,
            ISC_LOG_WARNING,
            "catz: 'coo' property PTR RRset contains "
            "more than one record, which is invalid");
    catz->broken = true;
    return ISC_R_FAILURE;
  }

  RETERR(dns_rdataset_first(value));

  dns_rdata_init(&rdata);
  dns_rdataset_current(value, &rdata);

  RETERR(dns_rdata_tostruct(&rdata, &ptr, NULL));

  if (dns_name_countlabels(&ptr.ptr) == 0) {
    CLEANUP(ISC_R_FAILURE);
  }

  CHECK(isc_ht_find(catz->entries, mhash->base, mhash->length,
        (void **)&entry));

  if (dns_name_countlabels(&entry->name) == 0) {
    CLEANUP(ISC_R_FAILURE);
  }

  coos_add(&catz->coos, entry, &ptr.ptr);

cleanup:
  dns_rdata_freestruct(&ptr);

  return result;
}

static isc_result_t
catz_process_zones_entry(dns_catz_zone_t *catz, dns_rdataset_t *value,
       dns_label_t *mhash) {
  isc_result_t result;
  dns_rdata_t rdata;
  dns_rdata_ptr_t ptr;
  dns_catz_entry_t *entry = NULL;

  if (value->type != dns_rdatatype_ptr) {
    return ISC_R_FAILURE;
  }

  if (dns_rdataset_count(value) != 1) {
    isc_log_write(DNS_LOGCATEGORY_GENERAL, DNS_LOGMODULE_CATZ,
            ISC_LOG_WARNING,
            "catz: member zone PTR RRset contains "
            "more than one record, which is invalid");
    catz->broken = true;
    return ISC_R_FAILURE;
  }

  RETERR(dns_rdataset_first(value));

  dns_rdata_init(&rdata);
  dns_rdataset_current(value, &rdata);

  RETERR(dns_rdata_tostruct(&rdata, &ptr, NULL));

  result = isc_ht_find(catz->entries, mhash->base, mhash->length,
           (void **)&entry);
  if (result == ISC_R_SUCCESS) {
    if (dns_name_countlabels(&entry->name) != 0) {
      /* We have a duplicate. */
      dns_rdata_freestruct(&ptr);
      return ISC_R_FAILURE;
    } else {
      dns_name_dup(&ptr.ptr, catz->catzs->mctx, &entry->name);
    }
  } else {
    entry = dns_catz_entry_new(catz->catzs->mctx, &ptr.ptr);

    result = isc_ht_add(catz->entries, mhash->base, mhash->length,
            entry);
  }
  INSIST(result == ISC_R_SUCCESS);

  dns_rdata_freestruct(&ptr);

  return ISC_R_SUCCESS;
}

static isc_result_t
catz_process_version(dns_catz_zone_t *catz, dns_rdataset_t *value) {
  isc_result_t result;
  dns_rdata_t rdata;
  dns_rdata_txt_t rdatatxt;
  dns_rdata_txt_string_t rdatastr;
  uint32_t tversion;
  char t[16];

  REQUIRE(DNS_CATZ_ZONE_VALID(catz));
  REQUIRE(DNS_RDATASET_VALID(value));

  if (value->type != dns_rdatatype_txt) {
    return ISC_R_FAILURE;
  }

  if (dns_rdataset_count(value) != 1) {
    isc_log_write(DNS_LOGCATEGORY_GENERAL, DNS_LOGMODULE_CATZ,
            ISC_LOG_WARNING,
            "catz: 'version' property TXT RRset contains "
            "more than one record, which is invalid");
    catz->broken = true;
    return ISC_R_FAILURE;
  }

  RETERR(dns_rdataset_first(value));

  dns_rdata_init(&rdata);
  dns_rdataset_current(value, &rdata);

  RETERR(dns_rdata_tostruct(&rdata, &rdatatxt, NULL));

  CHECK(dns_rdata_txt_first(&rdatatxt));

  CHECK(dns_rdata_txt_current(&rdatatxt, &rdatastr));

  result = dns_rdata_txt_next(&rdatatxt);
  if (result != ISC_R_NOMORE) {
    CLEANUP(ISC_R_FAILURE);
  }
  if (rdatastr.length > 15) {
    CLEANUP(ISC_R_BADNUMBER);
  }
  memmove(t, rdatastr.data, rdatastr.length);
  t[rdatastr.length] = 0;
  CHECK(isc_parse_uint32(&tversion, t, 10));
  catz->version = tversion;
  result = ISC_R_SUCCESS;

cleanup:
  dns_rdata_freestruct(&rdatatxt);
  if (result != ISC_R_SUCCESS) {
    isc_log_write(DNS_LOGCATEGORY_GENERAL, DNS_LOGMODULE_CATZ,
            ISC_LOG_WARNING,
            "catz: invalid record for the catalog "
            "zone version property");
    catz->broken = true;
  }
  return result;
}

static isc_result_t
catz_process_primaries(dns_catz_zone_t *catz, dns_ipkeylist_t *ipkl,
           dns_rdataset_t *value, dns_name_t *name) {
  isc_result_t result;
  dns_rdata_in_a_t rdata_a;
  dns_rdata_in_aaaa_t rdata_aaaa;
  dns_rdata_txt_t rdata_txt;
  dns_rdata_txt_string_t rdatastr;
  dns_name_t *keyname = NULL;
  isc_mem_t *mctx;
  char keycbuf[DNS_NAME_FORMATSIZE];
  isc_buffer_t keybuf;
  unsigned int rcount;

  REQUIRE(DNS_CATZ_ZONE_VALID(catz));
  REQUIRE(ipkl != NULL);
  REQUIRE(DNS_RDATASET_VALID(value));
  REQUIRE(dns_rdataset_isassociated(value));
  REQUIRE(ISC_MAGIC_VALID(name, DNS_NAME_MAGIC));

  mctx = catz->catzs->mctx;
  memset(&rdata_a, 0, sizeof(rdata_a));
  memset(&rdata_aaaa, 0, sizeof(rdata_aaaa));
  memset(&rdata_txt, 0, sizeof(rdata_txt));
  isc_buffer_init(&keybuf, keycbuf, sizeof(keycbuf));

  /*
   * We have three possibilities here:
   * - either empty name and IN A/IN AAAA record
   * - label and IN A/IN AAAA
   * - label and IN TXT - TSIG key name
   */
  if (name->length != 0) {
    dns_rdata_t rdata = DNS_RDATA_INIT;
    isc_sockaddr_t sockaddr;
    size_t i;

    /*
     * We're pre-preparing the data once, we'll put it into
     * the right spot in the primaries array once we find it.
     */
    result = dns_rdataset_first(value);
    RUNTIME_CHECK(result == ISC_R_SUCCESS);
    dns_rdataset_current(value, &rdata);
    switch (value->type) {
    case dns_rdatatype_a:
      result = dns_rdata_tostruct(&rdata, &rdata_a, NULL);
      RUNTIME_CHECK(result == ISC_R_SUCCESS);
      isc_sockaddr_fromin(&sockaddr, &rdata_a.in_addr, 0);
      dns_rdata_freestruct(&rdata_a);
      break;
    case dns_rdatatype_aaaa:
      result = dns_rdata_tostruct(&rdata, &rdata_aaaa, NULL);
      RUNTIME_CHECK(result == ISC_R_SUCCESS);
      isc_sockaddr_fromin6(&sockaddr, &rdata_aaaa.in6_addr,
               0);
      dns_rdata_freestruct(&rdata_aaaa);
      break;
    case dns_rdatatype_txt:
      result = dns_rdata_tostruct(&rdata, &rdata_txt, NULL);
      RUNTIME_CHECK(result == ISC_R_SUCCESS);

      result = dns_rdata_txt_first(&rdata_txt);
      if (result != ISC_R_SUCCESS) {
        dns_rdata_freestruct(&rdata_txt);
        return result;
      }

      result = dns_rdata_txt_current(&rdata_txt, &rdatastr);
      if (result != ISC_R_SUCCESS) {
        dns_rdata_freestruct(&rdata_txt);
        return result;
      }

      result = dns_rdata_txt_next(&rdata_txt);
      if (result != ISC_R_NOMORE) {
        dns_rdata_freestruct(&rdata_txt);
        return ISC_R_FAILURE;
      }

      /* rdatastr.length < DNS_NAME_MAXTEXT */
      keyname = isc_mem_get(mctx, sizeof(*keyname));
      dns_name_init(keyname);
      memmove(keycbuf, rdatastr.data, rdatastr.length);
      keycbuf[rdatastr.length] = 0;
      dns_rdata_freestruct(&rdata_txt);
      result = dns_name_fromstring(keyname, keycbuf,
                 dns_rootname, 0, mctx);
      if (result != ISC_R_SUCCESS) {
        isc_mem_put(mctx, keyname, sizeof(*keyname));
        return result;
      }
      break;
    default:
      return ISC_R_FAILURE;
    }

    /*
     * We have to find the appropriate labeled record in
     * primaries if it exists.  In the common case we'll
     * have no more than 3-4 records here, so no optimization.
     */
    for (i = 0; i < ipkl->count; i++) {
      if (ipkl->labels[i] != NULL &&
          !dns_name_compare(name, ipkl->labels[i]))
      {
        break;
      }
    }

    if (i < ipkl->count) { /* we have this record already */
      if (value->type == dns_rdatatype_txt) {
        if (ipkl->keys[i] != NULL) {
          if (dns_name_dynamic(ipkl->keys[i])) {
            dns_name_free(ipkl->keys[i],
                    mctx);
          }
          isc_mem_put(mctx, ipkl->keys[i],
                sizeof(*ipkl->keys[i]));
        }
        ipkl->keys[i] = keyname;
      } else { /* A/AAAA */
        memmove(&ipkl->addrs[i], &sockaddr,
          sizeof(sockaddr));
      }
    } else {
      dns_ipkeylist_resize(mctx, ipkl, i + 1);

      ipkl->labels[i] = isc_mem_get(mctx,
                  sizeof(*ipkl->labels[0]));
      dns_name_init(ipkl->labels[i]);
      dns_name_dup(name, mctx, ipkl->labels[i]);

      if (value->type == dns_rdatatype_txt) {
        ipkl->keys[i] = keyname;
      } else { /* A/AAAA */
        memmove(&ipkl->addrs[i], &sockaddr,
          sizeof(sockaddr));
      }
      ipkl->count++;
    }
    return ISC_R_SUCCESS;
  }
  /* else - 'simple' case - without labels */

  if (!dns_rdatatype_isaddr(value->type)) {
    return ISC_R_FAILURE;
  }

  rcount = dns_rdataset_count(value) + ipkl->count;

  dns_ipkeylist_resize(mctx, ipkl, rcount);

  DNS_RDATASET_FOREACH(value) {
    dns_rdata_t rdata = DNS_RDATA_INIT;
    dns_rdataset_current(value, &rdata);
    /*
     * port 0 == take the default
     */
    if (value->type == dns_rdatatype_a) {
      result = dns_rdata_tostruct(&rdata, &rdata_a, NULL);
      RUNTIME_CHECK(result == ISC_R_SUCCESS);
      isc_sockaddr_fromin(&ipkl->addrs[ipkl->count],
              &rdata_a.in_addr, 0);
      dns_rdata_freestruct(&rdata_a);
    } else {
      result = dns_rdata_tostruct(&rdata, &rdata_aaaa, NULL);
      RUNTIME_CHECK(result == ISC_R_SUCCESS);
      isc_sockaddr_fromin6(&ipkl->addrs[ipkl->count],
               &rdata_aaaa.in6_addr, 0);
      dns_rdata_freestruct(&rdata_aaaa);
    }
    ipkl->keys[ipkl->count] = NULL;
    ipkl->labels[ipkl->count] = NULL;
    ipkl->count++;
  }
  return ISC_R_SUCCESS;
}

static isc_result_t
catz_process_apl(dns_catz_zone_t *catz, isc_buffer_t **aclbp,
     dns_rdataset_t *value) {
  REQUIRE(DNS_RDATASET_VALID(value));
  REQUIRE(dns_rdataset_isassociated(value));

  if (value->type != dns_rdatatype_apl) {
    return ISC_R_FAILURE;
  }

  REQUIRE(DNS_CATZ_ZONE_VALID(catz));
  REQUIRE(aclbp != NULL);
  REQUIRE(*aclbp == NULL);

  isc_result_t result = ISC_R_SUCCESS;
  dns_rdata_t rdata;
  dns_rdata_in_apl_t rdata_apl;
  dns_rdata_apl_ent_t apl_ent;
  isc_netaddr_t addr;
  isc_buffer_t *aclb = NULL;
  unsigned char buf[256]; /* larger than INET6_ADDRSTRLEN */

  if (dns_rdataset_count(value) > 1) {
    isc_log_write(DNS_LOGCATEGORY_GENERAL, DNS_LOGMODULE_CATZ,
            ISC_LOG_WARNING,
            "catz: more than one APL entry for member zone, "
            "result is undefined");
  }
  result = dns_rdataset_first(value);
  RUNTIME_CHECK(result == ISC_R_SUCCESS);
  dns_rdata_init(&rdata);
  dns_rdataset_current(value, &rdata);
  RETERR(dns_rdata_tostruct(&rdata, &rdata_apl, catz->catzs->mctx));
  isc_buffer_allocate(catz->catzs->mctx, &aclb, 16);
  for (result = dns_rdata_apl_first(&rdata_apl); result == ISC_R_SUCCESS;
       result = dns_rdata_apl_next(&rdata_apl))
  {
    result = dns_rdata_apl_current(&rdata_apl, &apl_ent);
    RUNTIME_CHECK(result == ISC_R_SUCCESS);
    memset(buf, 0, sizeof(buf));
    if (apl_ent.data != NULL && apl_ent.length > 0) {
      memmove(buf, apl_ent.data, apl_ent.length);
    }
    if (apl_ent.family == 1) {
      isc_netaddr_fromin(&addr, (struct in_addr *)buf);
    } else if (apl_ent.family == 2) {
      isc_netaddr_fromin6(&addr, (struct in6_addr *)buf);
    } else {
      continue; /* xxxwpk log it or simply ignore? */
    }
    if (apl_ent.negative) {
      isc_buffer_putuint8(aclb, '!');
    }
    isc_buffer_reserve(aclb, INET6_ADDRSTRLEN);
    result = isc_netaddr_totext(&addr, aclb);
    RUNTIME_CHECK(result == ISC_R_SUCCESS);
    if ((apl_ent.family == 1 && apl_ent.prefix < 32) ||
        (apl_ent.family == 2 && apl_ent.prefix < 128))
    {
      isc_buffer_putuint8(aclb, '/');
      isc_buffer_printf(aclb, "%" PRId8, apl_ent.prefix);
    }
    isc_buffer_putstr(aclb, "; ");
  }
  if (result == ISC_R_NOMORE) {
    result = ISC_R_SUCCESS;
  } else {
    goto cleanup;
  }
  *aclbp = aclb;
  aclb = NULL;
cleanup:
  if (aclb != NULL) {
    isc_buffer_free(&aclb);
  }
  dns_rdata_freestruct(&rdata_apl);
  return result;
}

static isc_result_t
catz_process_zones_suboption(dns_catz_zone_t *catz, dns_rdataset_t *value,
           dns_label_t *mhash, dns_name_t *name) {
  isc_result_t result;
  dns_catz_entry_t *entry = NULL;
  dns_label_t option;
  dns_name_t prefix;
  catz_opt_t opt;
  unsigned int suffix_labels = 1;

  REQUIRE(DNS_CATZ_ZONE_VALID(catz));
  REQUIRE(mhash != NULL);
  REQUIRE(DNS_RDATASET_VALID(value));
  REQUIRE(ISC_MAGIC_VALID(name, DNS_NAME_MAGIC));

  uint8_t labels = dns_name_countlabels(name);

  if (labels < 1) {
    return ISC_R_FAILURE;
  }
  dns_name_getlabel(name, labels - 1, &option);
  opt = catz_get_option(&option);

  /*
   * The custom properties in version 2 schema must be placed under the
   * "ext" label.
   */
  if (catz->version >= 2 && opt >= CATZ_OPT_CUSTOM_START) {
    if (opt != CATZ_OPT_EXT || labels < 2) {
      return ISC_R_FAILURE;
    }
    suffix_labels++;
    dns_name_getlabel(name, labels - 2, &option);
    opt = catz_get_option(&option);
  }

  /*
   * We're adding this entry now, in case the option is invalid we'll get
   * rid of it in verification phase.
   */
  result = isc_ht_find(catz->entries, mhash->base, mhash->length,
           (void **)&entry);
  if (result != ISC_R_SUCCESS) {
    entry = dns_catz_entry_new(catz->catzs->mctx, NULL);
    result = isc_ht_add(catz->entries, mhash->base, mhash->length,
            entry);
  }
  INSIST(result == ISC_R_SUCCESS);

  dns_name_init(&prefix);
  dns_name_split(name, suffix_labels, &prefix, NULL);
  switch (opt) {
  case CATZ_OPT_COO:
    return catz_process_coo(catz, mhash, value);
  case CATZ_OPT_PRIMARIES:
    return catz_process_primaries(catz, &entry->opts.masters, value,
                &prefix);
  case CATZ_OPT_ALLOW_QUERY:;
    if (prefix.length != 0) {
      return ISC_R_FAILURE;
    }
    return catz_process_apl(catz, &entry->opts.allow_query, value);
  case CATZ_OPT_ALLOW_TRANSFER:
    if (prefix.length != 0) {
      return ISC_R_FAILURE;
    }
    return catz_process_apl(catz, &entry->opts.allow_transfer,
          value);
  default:
    return ISC_R_FAILURE;
  }

  return ISC_R_FAILURE;
}

static void
catz_entry_add_or_mod(dns_catz_zone_t *catz, isc_ht_t *ht, unsigned char *key,
          size_t keysize, dns_catz_entry_t *nentry,
          dns_catz_entry_t *oentry, const char *msg,
          const char *zname, const char *czname) {
  isc_result_t result = isc_ht_add(ht, key, (uint32_t)keysize, nentry);

  if (result != ISC_R_SUCCESS) {
    isc_log_write(DNS_LOGCATEGORY_GENERAL, DNS_LOGMODULE_CATZ,
            ISC_LOG_ERROR,
            "catz: error %s zone '%s' from catalog '%s' - %s",
            msg, zname, czname, isc_result_totext(result));
  }
  if (oentry != NULL) {
    dns_catz_entry_detach(catz, &oentry);
    result = isc_ht_delete(catz->entries, key, (uint32_t)keysize);
    RUNTIME_CHECK(result == ISC_R_SUCCESS);
  }
}

static isc_result_t
catz_process_value(dns_catz_zone_t *catz, dns_name_t *name,
       dns_rdataset_t *rdataset) {
  dns_label_t option;
  dns_name_t prefix;
  catz_opt_t opt;
  unsigned int suffix_labels = 1;

  REQUIRE(DNS_CATZ_ZONE_VALID(catz));
  REQUIRE(ISC_MAGIC_VALID(name, DNS_NAME_MAGIC));
  REQUIRE(DNS_RDATASET_VALID(rdataset));

  uint8_t labels = dns_name_countlabels(name);

  if (labels < 1) {
    return ISC_R_FAILURE;
  }
  dns_name_getlabel(name, labels - 1, &option);
  opt = catz_get_option(&option);

  /*
   * The custom properties in version 2 schema must be placed under the
   * "ext" label.
   */
  if (catz->version >= 2 && opt >= CATZ_OPT_CUSTOM_START) {
    if (opt != CATZ_OPT_EXT || labels < 2) {
      return ISC_R_FAILURE;
    }
    suffix_labels++;
    dns_name_getlabel(name, labels - 2, &option);
    opt = catz_get_option(&option);
  }

  dns_name_init(&prefix);
  dns_name_split(name, suffix_labels, &prefix, NULL);

  switch (opt) {
  case CATZ_OPT_ZONES:
    return catz_process_zones(catz, rdataset, &prefix);
  case CATZ_OPT_PRIMARIES:
    return catz_process_primaries(catz, &catz->zoneoptions.masters,
                rdataset, &prefix);
  case CATZ_OPT_ALLOW_QUERY:
    if (prefix.length != 0) {
      return ISC_R_FAILURE;
    }
    return catz_process_apl(catz, &catz->zoneoptions.allow_query,
          rdataset);
  case CATZ_OPT_ALLOW_TRANSFER:
    if (prefix.length != 0) {
      return ISC_R_FAILURE;
    }
    return catz_process_apl(catz, &catz->zoneoptions.allow_transfer,
          rdataset);
  case CATZ_OPT_VERSION:
    if (prefix.length != 0) {
      return ISC_R_FAILURE;
    }
    return catz_process_version(catz, rdataset);
  default:
    return ISC_R_FAILURE;
  }
}

/*%<
 * Process a single rdataset from a catalog zone 'catz' update, src_name is the
 * record name.
 *
 * Requires:
 * \li  'catz' is a valid dns_catz_zone_t.
 * \li  'src_name' is a valid dns_name_t.
 * \li  'rdataset' is valid rdataset.
 */
static isc_result_t
dns__catz_update_process(dns_catz_zone_t *catz, const dns_name_t *src_name,
       dns_rdataset_t *rdataset) {
  isc_result_t result;
  int order;
  unsigned int nlabels;
  dns_namereln_t nrres;
  dns_rdata_t rdata = DNS_RDATA_INIT;
  dns_rdata_soa_t soa;
  dns_name_t prefix;

  REQUIRE(DNS_CATZ_ZONE_VALID(catz));
  REQUIRE(ISC_MAGIC_VALID(src_name, DNS_NAME_MAGIC));

  if (rdataset->rdclass != dns_rdataclass_in) {
    isc_log_write(DNS_LOGCATEGORY_GENERAL, DNS_LOGMODULE_CATZ,
            ISC_LOG_ERROR,
            "catz: RR found which has a non-IN class");
    catz->broken = true;
    return ISC_R_FAILURE;
  }

  nrres = dns_name_fullcompare(src_name, &catz->name, &order, &nlabels);
  if (nrres == dns_namereln_equal) {
    if (rdataset->type == dns_rdatatype_soa) {
      RETERR(dns_rdataset_first(rdataset));

      dns_rdataset_current(rdataset, &rdata);
      result = dns_rdata_tostruct(&rdata, &soa, NULL);
      RUNTIME_CHECK(result == ISC_R_SUCCESS);

      /*
       * xxxwpk TODO do we want to save something from SOA?
       */
      dns_rdata_freestruct(&soa);
      return result;
    } else if (rdataset->type == dns_rdatatype_ns) {
      return ISC_R_SUCCESS;
    } else {
      return ISC_R_UNEXPECTED;
    }
  } else if (nrres != dns_namereln_subdomain) {
    return ISC_R_UNEXPECTED;
  }

  uint8_t labels = dns_name_countlabels(&catz->name);
  dns_name_init(&prefix);
  dns_name_split(src_name, labels, &prefix, NULL);
  result = catz_process_value(catz, &prefix, rdataset);

  return result;
}

static isc_result_t
digest2hex(unsigned char *digest, unsigned int digestlen, char *hash,
     size_t hashlen) {
  unsigned int i;
  for (i = 0; i < digestlen; i++) {
    size_t left = hashlen - i * 2;
    int ret = snprintf(hash + i * 2, left, "%02x", digest[i]);
    if (ret < 0 || (size_t)ret >= left) {
      return ISC_R_NOSPACE;
    }
  }
  return ISC_R_SUCCESS;
}

isc_result_t
dns_catz_generate_masterfilename(dns_catz_zone_t *catz, dns_catz_entry_t *entry,
         isc_buffer_t **buffer) {
  isc_buffer_t *tbuf = NULL;
  isc_region_t r;
  isc_result_t result;
  size_t rlen;
  bool special = false;

  REQUIRE(DNS_CATZ_ZONE_VALID(catz));
  REQUIRE(DNS_CATZ_ENTRY_VALID(entry));
  REQUIRE(buffer != NULL && *buffer != NULL);

  isc_buffer_allocate(catz->catzs->mctx, &tbuf,
          strlen(catz->catzs->view->name) +
            2 * DNS_NAME_FORMATSIZE + 2);

  isc_buffer_putstr(tbuf, catz->catzs->view->name);
  isc_buffer_putstr(tbuf, "_");
  CHECK(dns_name_totext(&catz->name, DNS_NAME_OMITFINALDOT, tbuf));

  isc_buffer_putstr(tbuf, "_");
  CHECK(dns_name_totext(&entry->name, DNS_NAME_OMITFINALDOT, tbuf));

  /*
   * Search for slash and other special characters in the view and
   * zone names.  Add a null terminator so we can use strpbrk(), then
   * remove it.
   */
  isc_buffer_putuint8(tbuf, 0);
  if (strpbrk(isc_buffer_base(tbuf), "\\/:%$") != NULL) {
    special = true;
  }
  isc_buffer_subtract(tbuf, 1);

  /* __catz__<digest>.db */
  rlen = (ISC_SHA256_DIGESTLENGTH * 2 + 1) + 12;

  /* optionally prepend with <zonedir>/ */
  if (entry->opts.zonedir != NULL) {
    rlen += strlen(entry->opts.zonedir) + 1;
  }

  CHECK(isc_buffer_reserve(*buffer, (unsigned int)rlen));

  if (entry->opts.zonedir != NULL) {
    isc_buffer_putstr(*buffer, entry->opts.zonedir);
    isc_buffer_putstr(*buffer, "/");
  }

  isc_buffer_usedregion(tbuf, &r);
  isc_buffer_putstr(*buffer, "__catz__");
  if (special || tbuf->used > ISC_SHA256_DIGESTLENGTH * 2 + 1) {
    unsigned char digest[ISC_MAX_MD_SIZE];
    unsigned int digestlen;

    /* we can do that because digest string < 2 * DNS_NAME */
    CHECK(isc_md(ISC_MD_SHA256, r.base, r.length, digest,
           &digestlen));
    CHECK(digest2hex(digest, digestlen, (char *)r.base,
         ISC_SHA256_DIGESTLENGTH * 2 + 1));
    isc_buffer_putstr(*buffer, (char *)r.base);
  } else {
    isc_buffer_copyregion(*buffer, &r);
  }

  isc_buffer_putstr(*buffer, ".db");
  result = ISC_R_SUCCESS;

cleanup:
  isc_buffer_free(&tbuf);
  return result;
}

/*
 * We have to generate a text buffer with regular zone config:
 * zone "foo.bar" {
 *  type secondary;
 *  primaries { ip1 port port1; ip2 port port2; };
 * }
 */
isc_result_t
dns_catz_generate_zonecfg(dns_catz_zone_t *catz, dns_catz_entry_t *entry,
        isc_buffer_t **buf) {
  isc_buffer_t *buffer = NULL;
  isc_region_t region;
  isc_result_t result;
  uint32_t i;
  isc_netaddr_t netaddr;
  char pbuf[sizeof("65535")]; /* used for port number */
  char namebuf[DNS_NAME_FORMATSIZE];

  REQUIRE(DNS_CATZ_ZONE_VALID(catz));
  REQUIRE(DNS_CATZ_ENTRY_VALID(entry));
  REQUIRE(buf != NULL && *buf == NULL);

  /*
   * The buffer will be reallocated if something won't fit,
   * ISC_BUFFER_INCR seems like a good start.
   */
  isc_buffer_allocate(catz->catzs->mctx, &buffer, ISC_BUFFER_INCR);

  isc_buffer_putstr(buffer, "zone \"");
  dns_name_format(&entry->name, namebuf, sizeof(namebuf));
  isc_buffer_putstr(buffer, namebuf);
  isc_buffer_putstr(buffer, "\" { type secondary; primaries");

  isc_buffer_putstr(buffer, " { ");
  for (i = 0; i < entry->opts.masters.count; i++) {
    /*
     * Every primary must have an IP address assigned.
     */
    switch (entry->opts.masters.addrs[i].type.sa.sa_family) {
    case AF_INET:
    case AF_INET6:
      break;
    default:
      dns_name_format(&entry->name, namebuf, sizeof(namebuf));
      isc_log_write(DNS_LOGCATEGORY_GENERAL,
              DNS_LOGMODULE_CATZ, ISC_LOG_ERROR,
              "catz: zone '%s' uses an invalid primary "
              "(no IP address assigned)",
              namebuf);
      CLEANUP(ISC_R_FAILURE);
    }
    isc_netaddr_fromsockaddr(&netaddr,
           &entry->opts.masters.addrs[i]);
    isc_buffer_reserve(buffer, INET6_ADDRSTRLEN);
    result = isc_netaddr_totext(&netaddr, buffer);
    RUNTIME_CHECK(result == ISC_R_SUCCESS);

    isc_buffer_putstr(buffer, " port ");
    snprintf(pbuf, sizeof(pbuf), "%u",
       isc_sockaddr_getport(&entry->opts.masters.addrs[i]));
    isc_buffer_putstr(buffer, pbuf);

    if (entry->opts.masters.keys[i] != NULL) {
      isc_buffer_putstr(buffer, " key ");
      dns_name_format(entry->opts.masters.keys[i], namebuf,
          sizeof(namebuf));
      isc_buffer_putstr(buffer, namebuf);
    }

    if (entry->opts.masters.tlss[i] != NULL) {
      isc_buffer_putstr(buffer, " tls ");
      dns_name_format(entry->opts.masters.tlss[i], namebuf,
          sizeof(namebuf));
      isc_buffer_putstr(buffer, namebuf);
    }
    isc_buffer_putstr(buffer, "; ");
  }
  isc_buffer_putstr(buffer, "}; ");
  if (!entry->opts.in_memory) {
    isc_buffer_putstr(buffer, "file \"");
    CHECK(dns_catz_generate_masterfilename(catz, entry, &buffer));
    isc_buffer_putstr(buffer, "\"; ");
  }
  if (entry->opts.allow_query != NULL) {
    isc_buffer_putstr(buffer, "allow-query { ");
    isc_buffer_usedregion(entry->opts.allow_query, &region);
    isc_buffer_copyregion(buffer, &region);
    isc_buffer_putstr(buffer, "}; ");
  }
  if (entry->opts.allow_transfer != NULL) {
    isc_buffer_putstr(buffer, "allow-transfer { ");
    isc_buffer_usedregion(entry->opts.allow_transfer, &region);
    isc_buffer_copyregion(buffer, &region);
    isc_buffer_putstr(buffer, "}; ");
  }

  isc_buffer_putstr(buffer, "};");
  *buf = buffer;

  return ISC_R_SUCCESS;

cleanup:
  isc_buffer_free(&buffer);
  return result;
}

static void
dns__catz_timer_cb(void *arg) {
  char domain[DNS_NAME_FORMATSIZE];
  dns_catz_zone_t *catz = (dns_catz_zone_t *)arg;

  REQUIRE(DNS_CATZ_ZONE_VALID(catz));

  if (atomic_load(&catz->catzs->shuttingdown)) {
    return;
  }

  LOCK(&catz->catzs->lock);

  INSIST(DNS_DB_VALID(catz->db));
  INSIST(catz->dbversion != NULL);
  INSIST(catz->updb == NULL);
  INSIST(catz->updbversion == NULL);

  catz->updatepending = false;
  catz->updaterunning = true;

  dns_name_format(&catz->name, domain, DNS_NAME_FORMATSIZE);

  if (!catz->active) {
    isc_log_write(DNS_LOGCATEGORY_GENERAL, DNS_LOGMODULE_CATZ,
            ISC_LOG_INFO,
            "catz: %s: no longer active, reload is canceled",
            domain);
    catz->updaterunning = false;
    goto exit;
  }

  dns_db_attach(catz->db, &catz->updb);
  catz->updbversion = catz->dbversion;
  catz->dbversion = NULL;

  isc_log_write(DNS_LOGCATEGORY_GENERAL, DNS_LOGMODULE_CATZ, ISC_LOG_INFO,
          "catz: %s: reload start", domain);

  dns_catz_zone_ref(catz);
  isc_work_enqueue(catz->loop, ISC_WORKLANE_SLOW, dns__catz_update_cb,
       dns__catz_done_cb, catz);

exit:
  isc_timer_destroy(&catz->updatetimer);
  catz->loop = NULL;

  catz->lastupdated = isc_time_now();

  UNLOCK(&catz->catzs->lock);
}

isc_result_t
dns_catz_dbupdate_callback(dns_db_t *db, void *fn_arg) {
  dns_catz_zones_t *catzs = NULL;
  dns_catz_zone_t *catz = NULL;
  isc_result_t result = ISC_R_SUCCESS;
  isc_region_t r;

  REQUIRE(DNS_DB_VALID(db));
  REQUIRE(DNS_CATZ_ZONES_VALID(fn_arg));
  catzs = (dns_catz_zones_t *)fn_arg;

  if (atomic_load(&catzs->shuttingdown)) {
    return ISC_R_SHUTTINGDOWN;
  }

  dns_name_toregion(&db->origin, &r);

  LOCK(&catzs->lock);
  if (catzs->zones == NULL) {
    CLEANUP(ISC_R_SHUTTINGDOWN);
  }
  CHECK(isc_ht_find(catzs->zones, r.base, r.length, (void **)&catz));

  /* New zone came as AXFR */
  if (catz->db != NULL && catz->db != db) {
    /* Old db cleanup. */
    if (catz->dbversion != NULL) {
      dns_db_closeversion(catz->db, &catz->dbversion, false);
    }
    dns_db_updatenotify_unregister(
      catz->db, dns_catz_dbupdate_callback, catz->catzs);
    dns_db_detach(&catz->db);
  }
  if (catz->db == NULL) {
    /* New db registration. */
    dns_db_attach(db, &catz->db);
    dns_db_updatenotify_register(db, dns_catz_dbupdate_callback,
               catz->catzs);
  }

  if (!catz->updatepending && !catz->updaterunning) {
    catz->updatepending = true;
    dns_db_currentversion(db, &catz->dbversion);
    dns__catz_timer_start(catz);
  } else {
    char dname[DNS_NAME_FORMATSIZE];

    catz->updatepending = true;
    dns_name_format(&catz->name, dname, DNS_NAME_FORMATSIZE);
    isc_log_write(DNS_LOGCATEGORY_GENERAL, DNS_LOGMODULE_CATZ,
            ISC_LOG_DEBUG(3),
            "catz: %s: update already queued or running",
            dname);
    if (catz->dbversion != NULL) {
      dns_db_closeversion(catz->db, &catz->dbversion, false);
    }
    dns_db_currentversion(catz->db, &catz->dbversion);
  }

cleanup:
  UNLOCK(&catzs->lock);

  return result;
}

void
dns_catz_dbupdate_unregister(dns_db_t *db, dns_catz_zones_t *catzs) {
  REQUIRE(DNS_DB_VALID(db));
  REQUIRE(DNS_CATZ_ZONES_VALID(catzs));

  dns_db_updatenotify_unregister(db, dns_catz_dbupdate_callback, catzs);
}

void
dns_catz_dbupdate_register(dns_db_t *db, dns_catz_zones_t *catzs) {
  REQUIRE(DNS_DB_VALID(db));
  REQUIRE(DNS_CATZ_ZONES_VALID(catzs));

  dns_db_updatenotify_register(db, dns_catz_dbupdate_callback, catzs);
}

static bool
catz_rdatatype_is_processable(const dns_rdatatype_t type) {
  return !dns_rdatatype_isdnssec(type) && type != dns_rdatatype_cds &&
         type != dns_rdatatype_cdnskey && type != dns_rdatatype_zonemd;
}

/*
 * Process an updated database for a catalog zone.
 * It creates a new catz, iterates over database to fill it with content, and
 * then merges new catz into old catz.
 */
static isc_result_t
dns__catz_update_cb(void *data) {
  dns_catz_zone_t *catz = (dns_catz_zone_t *)data;
  dns_db_t *updb = NULL;
  dns_catz_zones_t *catzs = NULL;
  dns_catz_zone_t *oldcatz = NULL, *newcatz = NULL;
  isc_result_t result;
  isc_region_t r;
  dns_dbnode_t *node = NULL;
  const dns_dbnode_t *vers_node = NULL;
  dns_dbiterator_t *updbit = NULL;
  dns_fixedname_t fixname;
  dns_name_t *name = NULL;
  dns_rdatasetiter_t *rdsiter = NULL;
  dns_rdataset_t rdataset;
  char bname[DNS_NAME_FORMATSIZE];
  char cname[DNS_NAME_FORMATSIZE];
  bool is_vers_processed = false;
  bool is_active;
  uint32_t vers;
  uint32_t catz_vers;

  REQUIRE(DNS_CATZ_ZONE_VALID(catz));
  REQUIRE(DNS_DB_VALID(catz->updb));
  REQUIRE(DNS_CATZ_ZONES_VALID(catz->catzs));

  updb = catz->updb;
  catzs = catz->catzs;

  if (atomic_load(&catzs->shuttingdown)) {
    return ISC_R_SHUTTINGDOWN;
  }

  dns_name_format(&updb->origin, bname, DNS_NAME_FORMATSIZE);

  /*
   * Create a new catz in the same context as current catz.
   */
  dns_name_toregion(&updb->origin, &r);
  LOCK(&catzs->lock);
  if (catzs->zones == NULL) {
    UNLOCK(&catzs->lock);
    return ISC_R_SHUTTINGDOWN;
  }
  result = isc_ht_find(catzs->zones, r.base, r.length, (void **)&oldcatz);
  is_active = (result == ISC_R_SUCCESS && oldcatz->active);
  UNLOCK(&catzs->lock);
  if (result != ISC_R_SUCCESS) {
    /* This can happen if we remove the zone in the meantime. */
    isc_log_write(DNS_LOGCATEGORY_GENERAL, DNS_LOGMODULE_CATZ,
            ISC_LOG_ERROR, "catz: zone '%s' not in config",
            bname);
    return result;
  }

  if (!is_active) {
    /* This can happen during a reconfiguration. */
    isc_log_write(DNS_LOGCATEGORY_GENERAL, DNS_LOGMODULE_CATZ,
            ISC_LOG_INFO,
            "catz: zone '%s' is no longer active", bname);
    return ISC_R_CANCELED;
  }

  result = dns_db_getsoaserial(updb, oldcatz->updbversion, &vers);
  if (result != ISC_R_SUCCESS) {
    /* A zone without SOA record?!? */
    isc_log_write(DNS_LOGCATEGORY_GENERAL, DNS_LOGMODULE_CATZ,
            ISC_LOG_ERROR,
            "catz: zone '%s' has no SOA record (%s)", bname,
            isc_result_totext(result));
    return result;
  }

  isc_log_write(DNS_LOGCATEGORY_GENERAL, DNS_LOGMODULE_CATZ, ISC_LOG_INFO,
          "catz: updating catalog zone '%s' with serial %" PRIu32,
          bname, vers);

  result = dns_db_createiterator(updb, DNS_DB_NONSEC3, &updbit);
  if (result != ISC_R_SUCCESS) {
    isc_log_write(DNS_LOGCATEGORY_GENERAL, DNS_LOGMODULE_CATZ,
            ISC_LOG_ERROR,
            "catz: failed to create DB iterator - %s",
            isc_result_totext(result));
    return result;
  }

  name = dns_fixedname_initname(&fixname);

  /*
   * Take the version record to process first, because the other
   * records might be processed differently depending on the version of
   * the catalog zone's schema.
   */
  result = dns_name_fromstring(name, "version", &updb->origin, 0, NULL);
  if (result != ISC_R_SUCCESS) {
    dns_dbiterator_destroy(&updbit);
    isc_log_write(DNS_LOGCATEGORY_GENERAL, DNS_LOGMODULE_CATZ,
            ISC_LOG_ERROR,
            "catz: failed to create name from string - %s",
            isc_result_totext(result));
    return result;
  }

  result = dns_dbiterator_seek(updbit, name);
  if (result != ISC_R_SUCCESS) {
    dns_dbiterator_destroy(&updbit);
    isc_log_write(DNS_LOGCATEGORY_GENERAL, DNS_LOGMODULE_CATZ,
            ISC_LOG_ERROR,
            "catz: zone '%s' has no 'version' record (%s) "
            "and will not be processed",
            bname, isc_result_totext(result));

    return result;
  }

  newcatz = dns_catz_zone_new(catzs, &updb->origin);
  name = dns_fixedname_initname(&fixname);

  /*
   * Iterate over database to fill the new zone.
   */
  while (result == ISC_R_SUCCESS) {
    if (atomic_load(&catzs->shuttingdown)) {
      result = ISC_R_SHUTTINGDOWN;
      break;
    }

    result = dns_dbiterator_current(updbit, &node, name);
    if (result != ISC_R_SUCCESS) {
      isc_log_write(DNS_LOGCATEGORY_GENERAL,
              DNS_LOGMODULE_CATZ, ISC_LOG_ERROR,
              "catz: failed to get db iterator - %s",
              isc_result_totext(result));
      break;
    }

    result = dns_dbiterator_pause(updbit);
    RUNTIME_CHECK(result == ISC_R_SUCCESS);

    if (!is_vers_processed) {
      /* Keep the version node to skip it later in the loop */
      vers_node = node;
    } else if (node == vers_node) {
      /* Skip the already processed version node */
      dns_db_detachnode(&node);
      result = dns_dbiterator_next(updbit);
      continue;
    }

    result = dns_db_allrdatasets(updb, node, oldcatz->updbversion,
               0, 0, &rdsiter);
    if (result != ISC_R_SUCCESS) {
      isc_log_write(DNS_LOGCATEGORY_GENERAL,
              DNS_LOGMODULE_CATZ, ISC_LOG_ERROR,
              "catz: failed to fetch rrdatasets - %s",
              isc_result_totext(result));
      dns_db_detachnode(&node);
      break;
    }

    dns_rdataset_init(&rdataset);
    DNS_RDATASETITER_FOREACH(rdsiter) {
      dns_rdatasetiter_current(rdsiter, &rdataset);

      /*
       * Skip processing DNSSEC-related and ZONEMD types,
       * because we are not interested in them in the context
       * of a catalog zone, and processing them will fail
       * and produce an unnecessary warning message.
       */
      if (!catz_rdatatype_is_processable(rdataset.type)) {
        dns_rdataset_disassociate(&rdataset);
        continue;
      }

      result = dns__catz_update_process(newcatz, name,
                &rdataset);
      if (result != ISC_R_SUCCESS) {
        char typebuf[DNS_RDATATYPE_FORMATSIZE];
        char classbuf[DNS_RDATACLASS_FORMATSIZE];

        dns_name_format(name, cname,
            DNS_NAME_FORMATSIZE);
        dns_rdataclass_format(rdataset.rdclass,
                  classbuf,
                  sizeof(classbuf));
        dns_rdatatype_format(rdataset.type, typebuf,
                 sizeof(typebuf));
        isc_log_write(DNS_LOGCATEGORY_GENERAL,
                DNS_LOGMODULE_CATZ,
                ISC_LOG_WARNING,
                "catz: invalid record in catalog "
                "zone - %s %s %s (%s) - ignoring",
                cname, classbuf, typebuf,
                isc_result_totext(result));
      }

      dns_rdataset_disassociate(&rdataset);
    }

    dns_rdatasetiter_destroy(&rdsiter);

    dns_db_detachnode(&node);

    if (!is_vers_processed) {
      is_vers_processed = true;
      result = dns_dbiterator_first(updbit);
    } else {
      result = dns_dbiterator_next(updbit);
    }
  }

  dns_dbiterator_destroy(&updbit);
  isc_log_write(DNS_LOGCATEGORY_GENERAL, DNS_LOGMODULE_CATZ,
          ISC_LOG_DEBUG(3),
          "catz: update_from_db: iteration finished: %s",
          isc_result_totext(result));

  /*
   * Check catalog zone version compatibilites.
   */
  catz_vers = (newcatz->version == DNS_CATZ_VERSION_UNDEFINED)
          ? oldcatz->version
          : newcatz->version;
  if (catz_vers == DNS_CATZ_VERSION_UNDEFINED) {
    isc_log_write(DNS_LOGCATEGORY_GENERAL, DNS_LOGMODULE_CATZ,
            ISC_LOG_WARNING,
            "catz: zone '%s' version is not set", bname);
    newcatz->broken = true;
  } else if (catz_vers != 1 && catz_vers != 2) {
    isc_log_write(DNS_LOGCATEGORY_GENERAL, DNS_LOGMODULE_CATZ,
            ISC_LOG_WARNING,
            "catz: zone '%s' unsupported version "
            "'%" PRIu32 "'",
            bname, catz_vers);
    newcatz->broken = true;
  } else {
    oldcatz->version = catz_vers;
  }

  if (newcatz->broken) {
    dns_name_format(name, cname, DNS_NAME_FORMATSIZE);
    isc_log_write(DNS_LOGCATEGORY_GENERAL, DNS_LOGMODULE_CATZ,
            ISC_LOG_ERROR,
            "catz: new catalog zone '%s' is broken and "
            "will not be processed",
            bname);
    dns_catz_zone_detach(&newcatz);
    return ISC_R_FAILURE;
  }

  /*
   * Finally merge new zone into old zone.
   */
  result = dns__catz_zones_merge(oldcatz, newcatz);
  dns_catz_zone_detach(&newcatz);
  if (result != ISC_R_SUCCESS) {
    isc_log_write(DNS_LOGCATEGORY_GENERAL, DNS_LOGMODULE_CATZ,
            ISC_LOG_ERROR, "catz: failed merging zones: %s",
            isc_result_totext(result));

    return result;
  }

  isc_log_write(DNS_LOGCATEGORY_GENERAL, DNS_LOGMODULE_CATZ,
          ISC_LOG_DEBUG(3),
          "catz: update_from_db: new zone merged");

  return result;
}

static void
dns__catz_done_cb(void *data, isc_result_t result) {
  dns_catz_zone_t *catz = (dns_catz_zone_t *)data;
  char dname[DNS_NAME_FORMATSIZE];

  REQUIRE(DNS_CATZ_ZONE_VALID(catz));

  LOCK(&catz->catzs->lock);
  catz->updaterunning = false;

  dns_name_format(&catz->name, dname, DNS_NAME_FORMATSIZE);

  if (catz->updatepending && !atomic_load(&catz->catzs->shuttingdown)) {
    /* Restart the timer */
    dns__catz_timer_start(catz);
  }

  dns_db_closeversion(catz->updb, &catz->updbversion, false);
  dns_db_detach(&catz->updb);

  UNLOCK(&catz->catzs->lock);

  isc_log_write(DNS_LOGCATEGORY_GENERAL, DNS_LOGMODULE_CATZ, ISC_LOG_INFO,
          "catz: %s: reload done: %s", dname,
          isc_result_totext(result));

  dns_catz_zone_unref(catz);
}

void
dns_catz_prereconfig(dns_catz_zones_t *catzs) {
  isc_result_t result;
  isc_ht_iter_t *iter = NULL;

  REQUIRE(DNS_CATZ_ZONES_VALID(catzs));

  LOCK(&catzs->lock);
  isc_ht_iter_create(catzs->zones, &iter);
  for (result = isc_ht_iter_first(iter); result == ISC_R_SUCCESS;
       result = isc_ht_iter_next(iter))
  {
    dns_catz_zone_t *catz = NULL;
    isc_ht_iter_current(iter, (void **)&catz);
    catz->active = false;
  }
  UNLOCK(&catzs->lock);
  INSIST(result == ISC_R_NOMORE);
  isc_ht_iter_destroy(&iter);
}

void
dns_catz_postreconfig(dns_catz_zones_t *catzs) {
  isc_result_t result;
  dns_catz_zone_t *newcatz = NULL;
  isc_ht_iter_t *iter = NULL;

  REQUIRE(DNS_CATZ_ZONES_VALID(catzs));

  LOCK(&catzs->lock);
  isc_ht_iter_create(catzs->zones, &iter);
  for (result = isc_ht_iter_first(iter); result == ISC_R_SUCCESS;) {
    dns_catz_zone_t *catz = NULL;

    isc_ht_iter_current(iter, (void **)&catz);
    if (!catz->active) {
      char cname[DNS_NAME_FORMATSIZE];
      dns_name_format(&catz->name, cname,
          DNS_NAME_FORMATSIZE);
      isc_log_write(DNS_LOGCATEGORY_GENERAL,
              DNS_LOGMODULE_CATZ, ISC_LOG_WARNING,
              "catz: removing catalog zone %s", cname);

      /*
       * Merge the old zone with an empty one to remove
       * all members.
       */
      newcatz = dns_catz_zone_new(catzs, &catz->name);
      dns__catz_zones_merge(catz, newcatz);
      dns_catz_zone_detach(&newcatz);

      /* Make sure that we have an empty catalog zone. */
      INSIST(isc_ht_count(catz->entries) == 0);
      result = isc_ht_iter_delcurrent_next(iter);
      dns_catz_zone_detach(&catz);
    } else {
      result = isc_ht_iter_next(iter);
    }
  }
  UNLOCK(&catzs->lock);
  RUNTIME_CHECK(result == ISC_R_NOMORE);
  isc_ht_iter_destroy(&iter);
}

void
dns_catz_zone_prereconfig(dns_catz_zone_t *catz) {
  LOCK(&catz->lock);
}

void
dns_catz_zone_postreconfig(dns_catz_zone_t *catz) {
  UNLOCK(&catz->lock);
}

void
dns_catz_zone_for_each_entry2(dns_catz_zone_t *catz, dns_catz_entry_cb2 cb,
            void *arg1, void *arg2) {
  REQUIRE(DNS_CATZ_ZONE_VALID(catz));

  isc_ht_iter_t *iter = NULL;
  isc_result_t result;

  LOCK(&catz->catzs->lock);
  isc_ht_iter_create(catz->entries, &iter);
  for (result = isc_ht_iter_first(iter); result == ISC_R_SUCCESS;
       result = isc_ht_iter_next(iter))
  {
    dns_catz_entry_t *entry = NULL;

    isc_ht_iter_current(iter, (void **)&entry);
    cb(entry, arg1, arg2);
  }
  isc_ht_iter_destroy(&iter);
  UNLOCK(&catz->catzs->lock);
}

Coverage Report

Created: 2026-07-16 07:05