zone.c

bind-3.2.

	result = dns_master_loadfileinc(load->zone->masterfile,
					dns_db_origin(load->db),
					dns_db_origin(load->db),
					load->zone->rdclass,
					options,
					&load->callbacks, task,
					zone_loaddone, load,
					&load->zone->lctx, load->zone->mctx);
	if (result != ISC_R_SUCCESS && result != DNS_R_CONTINUE &&
	    result != DNS_R_SEENINCLUDE)
		goto fail;
	return;

 fail:
	zone_loaddone(load, result);
}

static isc_result_t
zone_startload(dns_db_t *db, dns_zone_t *zone, isc_time_t loadtime) {
	dns_load_t *load;
	isc_result_t result;
	isc_result_t tresult;
	unsigned int options;

	options = DNS_MASTER_ZONE;
	if (DNS_ZONE_OPTION(zone, DNS_ZONEOPT_MANYERRORS))
		options |= DNS_MASTER_MANYERRORS;
	if (zone->type == dns_zone_slave)
		options |= DNS_MASTER_SLAVE;
	if (zone->zmgr != NULL && zone->db != NULL && zone->task != NULL) {
		load = isc_mem_get(zone->mctx, sizeof(*load));
		if (load == NULL)
			return (ISC_R_NOMEMORY);

		load->mctx = NULL;
		load->zone = NULL;
		load->db = NULL;
		load->loadtime = loadtime;
		load->magic = LOAD_MAGIC;

		isc_mem_attach(zone->mctx, &load->mctx);
		zone_iattach(zone, &load->zone);
		dns_db_attach(db, &load->db);
		dns_rdatacallbacks_init(&load->callbacks);
		result = dns_db_beginload(db, &load->callbacks.add,
					  &load->callbacks.add_private);
		if (result != ISC_R_SUCCESS)
			goto cleanup;
		result = zonemgr_getio(zone->zmgr, ISC_TRUE, zone->task, 
				       zone_gotreadhandle, load,
				       &zone->readio);
		if (result != ISC_R_SUCCESS) {
			tresult = dns_db_endload(load->db,
						 &load->callbacks.add_private);
			if (result == ISC_R_SUCCESS)
				result = tresult;
			goto cleanup;
		} else
			result = DNS_R_CONTINUE;
	} else if (DNS_ZONE_OPTION(zone, DNS_ZONEOPT_MANYERRORS)) {
		dns_rdatacallbacks_t    callbacks;

		dns_rdatacallbacks_init(&callbacks);
		result = dns_db_beginload(db, &callbacks.add,
					  &callbacks.add_private);
		if (result != ISC_R_SUCCESS)
			return (result);
		result = dns_master_loadfile(zone->masterfile, &zone->origin,
					     &zone->origin, zone->rdclass,
					     options, &callbacks, zone->mctx);
		tresult = dns_db_endload(db, &callbacks.add_private);
		if (result == ISC_R_SUCCESS)
			result = tresult;
	} else {
		result = dns_db_load(db, zone->masterfile);
	}

	return (result);

 cleanup:
	load->magic = 0;
	dns_db_detach(&load->db);
	zone_idetach(&load->zone);
	isc_mem_detach(&load->mctx);
	isc_mem_put(zone->mctx, load, sizeof(*load));
	return (result);
}

static isc_result_t
zone_postload(dns_zone_t *zone, dns_db_t *db, isc_time_t loadtime,
	      isc_result_t result)
{
	unsigned int soacount = 0;
	unsigned int nscount = 0;
	isc_uint32_t serial, refresh, retry, expire, minimum;
	isc_time_t now;
	isc_boolean_t needdump = ISC_FALSE;

	isc_time_now(&now);

	/*
	 * Initiate zone transfer?  We may need a error code that
	 * indicates that the "permanent" form does not exist.
	 * XXX better error feedback to log.
	 */
	if (result != ISC_R_SUCCESS && result != DNS_R_SEENINCLUDE) {
		if (zone->type == dns_zone_slave ||
		    zone->type == dns_zone_stub) {
			if (result == ISC_R_FILENOTFOUND)
				dns_zone_log(zone, ISC_LOG_DEBUG(1),
					     "no master file");
			else if (result != DNS_R_NOMASTERFILE)
				dns_zone_log(zone, ISC_LOG_ERROR,
					     "loading master file %s: %s",
					     zone->masterfile,
					     dns_result_totext(result));
		} else
			dns_zone_log(zone, ISC_LOG_ERROR,
				     "loading master file %s: %s",
				     zone->masterfile,
				     dns_result_totext(result));
		goto cleanup;
	}

	dns_zone_log(zone, ISC_LOG_DEBUG(2),
		     "number of nodes in database: %u",
		     dns_db_nodecount(db));
	zone->loadtime = loadtime;

	dns_zone_log(zone, ISC_LOG_DEBUG(1), "loaded");

	if (result == DNS_R_SEENINCLUDE)
		DNS_ZONE_SETFLAG(zone, DNS_ZONEFLG_HASINCLUDE);
	else
		DNS_ZONE_CLRFLAG(zone, DNS_ZONEFLG_HASINCLUDE);
	/*
	 * Apply update log, if any.
	 */
	if (zone->journal != NULL &&
	    ! DNS_ZONE_OPTION(zone, DNS_ZONEOPT_NOMERGE)) {
		result = dns_journal_rollforward(zone->mctx, db,
						 zone->journal);
		if (result != ISC_R_SUCCESS && result != ISC_R_NOTFOUND &&
		    result != DNS_R_UPTODATE && result != DNS_R_NOJOURNAL &&
		    result != ISC_R_RANGE) {
			dns_zone_log(zone, ISC_LOG_ERROR,
				     "journal rollforward failed: %s",
				     dns_result_totext(result));
			goto cleanup;
		}
		if (result == ISC_R_NOTFOUND || result == ISC_R_RANGE) {
			dns_zone_log(zone, ISC_LOG_ERROR,
				     "journal rollforward failed: "
				     "journal out of sync with zone");
			goto cleanup;
		}
		dns_zone_log(zone, ISC_LOG_DEBUG(1),
			     "journal rollforward completed "
			     "successfully: %s",
			     dns_result_totext(result));
		if (result == ISC_R_SUCCESS)
			needdump = ISC_TRUE;
	}

	/*
	 * Obtain ns and soa counts for top of zone.
	 */
	nscount = 0;
	soacount = 0;
	INSIST(db != NULL);
	result = zone_get_from_db(db, &zone->origin, &nscount,
				  &soacount, &serial, &refresh, &retry,
				  &expire, &minimum);
	if (result != ISC_R_SUCCESS) {
		dns_zone_log(zone, ISC_LOG_ERROR,
			     "could not find NS and/or SOA records");
	}

	/*
	 * Master / Slave / Stub zones require both NS and SOA records at
	 * the top of the zone.
	 */

	switch (zone->type) {
	case dns_zone_master:
	case dns_zone_slave:
	case dns_zone_stub:
		if (soacount != 1) {
			dns_zone_log(zone, ISC_LOG_ERROR,
				     "has %d SOA records", soacount);
			result = DNS_R_BADZONE;
		}
		if (nscount == 0) {
			dns_zone_log(zone, ISC_LOG_ERROR,
				     "has no NS records");
			result = DNS_R_BADZONE;
		}
		if (result != ISC_R_SUCCESS)
			goto cleanup;
		if (zone->db != NULL) {
			if (!isc_serial_ge(serial, zone->serial)) {
				dns_zone_log(zone, ISC_LOG_ERROR,
					     "zone serial has gone backwards");
			}
		}
		zone->serial = serial;
		zone->refresh = RANGE(refresh,
				      zone->minrefresh, zone->maxrefresh);
		zone->retry = RANGE(retry,
				    zone->minretry, zone->maxretry);
		zone->expire = RANGE(expire, zone->refresh + zone->retry,
				     DNS_MAX_EXPIRE);
		zone->minimum = minimum;
		DNS_ZONE_SETFLAG(zone, DNS_ZONEFLG_HAVETIMERS);

		if (zone->type == dns_zone_slave ||
		    zone->type == dns_zone_stub) {
			isc_time_t t;
			isc_interval_t i;
			unsigned int delay;

			result = isc_file_getmodtime(zone->journal, &t);
			if (result != ISC_R_SUCCESS)
				result = isc_file_getmodtime(zone->masterfile,
							     &t);

			if (result == ISC_R_SUCCESS) {
				isc_interval_set(&i, zone->expire, 0);
				isc_time_add(&t, &i, &zone->expiretime);
			} else {
				isc_interval_set(&i, zone->retry, 0);
				isc_time_add(&now, &i, &zone->expiretime);
			}
			delay = isc_random_jitter(zone->retry,
						  (zone->retry * 3) / 4);
			isc_interval_set(&i, delay, 0);
			isc_time_add(&now, &i, &zone->refreshtime);
			if (isc_time_compare(&zone->refreshtime,   
					     &zone->expiretime) >= 0)
				zone->refreshtime = now;
		}
		break;
	default:
		UNEXPECTED_ERROR(__FILE__, __LINE__,
				 "unexpected zone type %d", zone->type);
		result = ISC_R_UNEXPECTED;
		goto cleanup;
	}


#if 0
	/* destroy notification example. */
	{
		isc_event_t *e = isc_event_allocate(zone->mctx, NULL,
						    DNS_EVENT_DBDESTROYED,
						    dns_zonemgr_dbdestroyed,
						    zone,
						    sizeof(isc_event_t));
		dns_db_ondestroy(db, zone->task, &e);
	}
#endif

	if (zone->db != NULL) {
		result = zone_replacedb(zone, db, ISC_FALSE);
		if (result != ISC_R_SUCCESS)
			goto cleanup;
	} else {
		dns_db_attach(db, &zone->db);
		DNS_ZONE_SETFLAG(zone,
				 DNS_ZONEFLG_LOADED|DNS_ZONEFLG_NEEDNOTIFY);
	}
	result = ISC_R_SUCCESS;
	if (needdump)
		zone_needdump(zone, DNS_DUMP_DELAY);
	if (zone->task != NULL)
		zone_settimer(zone, &now);
	dns_zone_log(zone, ISC_LOG_INFO, "loaded serial %u", zone->serial);
	return (result);

 cleanup:
	if (zone->type == dns_zone_slave ||
	    zone->type == dns_zone_stub) {
		if (zone->journal != NULL)
			zone_saveunique(zone, zone->journal, "jn-XXXXXXXX");
		if (zone->masterfile != NULL)
			zone_saveunique(zone, zone->masterfile, "db-XXXXXXXX");

		/* Mark the zone for immediate refresh. */
		zone->refreshtime = now;
		if (zone->task != NULL)
			zone_settimer(zone, &now);
		result = ISC_R_SUCCESS;
	}
	return (result);
}

static isc_boolean_t
exit_check(dns_zone_t *zone) {

	REQUIRE(LOCKED_ZONE(zone));

	if (DNS_ZONE_FLAG(zone, DNS_ZONEFLG_SHUTDOWN) &&
	    zone->irefs == 0)
	{
		/*
		 * DNS_ZONEFLG_SHUTDOWN can only be set if erefs == 0.
		 */
		INSIST(isc_refcount_current(&zone->erefs) == 0);
		return (ISC_TRUE);
	}
	return (ISC_FALSE);
}

static isc_result_t
zone_count_ns_rr(dns_db_t *db, dns_dbnode_t *node, dns_dbversion_t *version,
		 unsigned int *nscount)
{
	isc_result_t result;
	unsigned int count;
	dns_rdataset_t rdataset;

	REQUIRE(nscount != NULL);

	dns_rdataset_init(&rdataset);
	result = dns_db_findrdataset(db, node, version, dns_rdatatype_ns,
				     dns_rdatatype_none, 0, &rdataset, NULL);
	if (result == ISC_R_NOTFOUND) {
		*nscount = 0;
		result = ISC_R_SUCCESS;
		goto invalidate_rdataset;
	}
	else if (result != ISC_R_SUCCESS)
		goto invalidate_rdataset;

	count = 0;
	result = dns_rdataset_first(&rdataset);
	while (result == ISC_R_SUCCESS) {
		count++;
		result = dns_rdataset_next(&rdataset);
	}
	dns_rdataset_disassociate(&rdataset);

	*nscount = count;
	result = ISC_R_SUCCESS;

 invalidate_rdataset:
	dns_rdataset_invalidate(&rdataset);

	return (result);
}

static isc_result_t
zone_load_soa_rr(dns_db_t *db, dns_dbnode_t *node, dns_dbversion_t *version,
		 unsigned int *soacount,
		 isc_uint32_t *serial, isc_uint32_t *refresh,
		 isc_uint32_t *retry, isc_uint32_t *expire,
		 isc_uint32_t *minimum)
{
	isc_result_t result;
	unsigned int count;
	dns_rdataset_t rdataset;
	dns_rdata_t rdata = DNS_RDATA_INIT;
	dns_rdata_soa_t soa;

	dns_rdataset_init(&rdataset);
	result = dns_db_findrdataset(db, node, version, dns_rdatatype_soa,
				     dns_rdatatype_none, 0, &rdataset, NULL);
	if (result != ISC_R_SUCCESS)
		goto invalidate_rdataset;

	count = 0;
	result = dns_rdataset_first(&rdataset);
	while (result == ISC_R_SUCCESS) {
		dns_rdata_init(&rdata);
		dns_rdataset_current(&rdataset, &rdata);
		count++;
		if (count == 1)
			dns_rdata_tostruct(&rdata, &soa, NULL);

		result = dns_rdataset_next(&rdataset);
		dns_rdata_reset(&rdata);
	}
	dns_rdataset_disassociate(&rdataset);

	if (soacount != NULL)
		*soacount = count;

	if (count > 0) {
		if (serial != NULL)
			*serial = soa.serial;
		if (refresh != NULL)
			*refresh = soa.refresh;
		if (retry != NULL)
			*retry = soa.retry;
		if (expire != NULL)
			*expire = soa.expire;
		if (minimum != NULL)
			*minimum = soa.minimum;
	}

	result = ISC_R_SUCCESS;

 invalidate_rdataset:
	dns_rdataset_invalidate(&rdataset);

	return (result);
}

/*
 * zone must be locked.
 */
static isc_result_t
zone_get_from_db(dns_db_t *db, dns_name_t *origin, unsigned int *nscount,
		 unsigned int *soacount, isc_uint32_t *serial,
		 isc_uint32_t *refresh, isc_uint32_t *retry,
		 isc_uint32_t *expire, isc_uint32_t *minimum)
{
	dns_dbversion_t *version;
	isc_result_t result;
	isc_result_t answer = ISC_R_SUCCESS;
	dns_dbnode_t *node;

	REQUIRE(db != NULL);
	REQUIRE(origin != NULL);

	version = NULL;
	dns_db_currentversion(db, &version);

	node = NULL;
	result = dns_db_findnode(db, origin, ISC_FALSE, &node);
	if (result != ISC_R_SUCCESS) {
		answer = result;
		goto closeversion;
	}

	if (nscount != NULL) {
		result = zone_count_ns_rr(db, node, version, nscount);
		if (result != ISC_R_SUCCESS)
			answer = result;
	}

	if (soacount != NULL || serial != NULL || refresh != NULL
	    || retry != NULL || expire != NULL || minimum != NULL) {
		result = zone_load_soa_rr(db, node, version, soacount,
					  serial, refresh, retry, expire,
					  minimum);
		if (result != ISC_R_SUCCESS)
			answer = result;
	}

	dns_db_detachnode(db, &node);
 closeversion:
	dns_db_closeversion(db, &version, ISC_FALSE);

	return (answer);
}

void
dns_zone_attach(dns_zone_t *source, dns_zone_t **target) {
	REQUIRE(DNS_ZONE_VALID(source));
	REQUIRE(target != NULL && *target == NULL);
	isc_refcount_increment(&source->erefs, NULL);
	*target = source;
}

void
dns_zone_detach(dns_zone_t **zonep) {
	dns_zone_t *zone;
	unsigned int refs;
	isc_boolean_t free_now = ISC_FALSE;

	REQUIRE(zonep != NULL && DNS_ZONE_VALID(*zonep));

	zone = *zonep;

	isc_refcount_decrement(&zone->erefs, &refs);

	if (refs == 0) {
		LOCK_ZONE(zone);
		/*
		 * We just detached the last external reference.
		 */
		if (zone->task != NULL) {
			/*
			 * This zone is being managed.  Post
			 * its control event and let it clean
			 * up synchronously in the context of
			 * its task.
			 */
			isc_event_t *ev = &zone->ctlevent;
			isc_task_send(zone->task, &ev);
		} else {
			/*
			 * This zone is not being managed; it has
			 * no task and can have no outstanding
			 * events.  Free it immediately.
			 */
			/*
			 * Unmanaged zones should not have non-null views;
			 * we have no way of detaching from the view here
			 * without causing deadlock because this code is called
			 * with the view already locked.
			 */
			INSIST(zone->view == NULL);
			free_now = ISC_TRUE;
		}
		UNLOCK_ZONE(zone);
	}
	*zonep = NULL;
	if (free_now)
		zone_free(zone);
}

void
dns_zone_iattach(dns_zone_t *source, dns_zone_t **target) {
	REQUIRE(DNS_ZONE_VALID(source));
	REQUIRE(target != NULL && *target == NULL);
	LOCK_ZONE(source);
	zone_iattach(source, target);
	UNLOCK_ZONE(source);
}

static void
zone_iattach(dns_zone_t *source, dns_zone_t **target) {

	/*
	 * 'source' locked by caller.
	 */