zone.c

bind-3.2.

	zone->view = NULL;
	ISC_LINK_INIT(zone, statelink);
	zone->statelist = NULL;
	zone->counters = NULL;

	zone->magic = ZONE_MAGIC;

	/* Must be after magic is set. */
	result = dns_zone_setdbtype(zone, dbargc_default, dbargv_default);
	if (result != ISC_R_SUCCESS)
		goto free_mutex;
	
	ISC_EVENT_INIT(&zone->ctlevent, sizeof(zone->ctlevent), 0, NULL,
		       DNS_EVENT_ZONECONTROL, zone_shutdown, zone, zone,
		       NULL, NULL);
	*zonep = zone;
	return (ISC_R_SUCCESS);

 free_mutex:
	DESTROYLOCK(&zone->lock);
	return (ISC_R_NOMEMORY);
}

/*
 * Free a zone.  Because we require that there be no more
 * outstanding events or references, no locking is necessary.
 */
static void
zone_free(dns_zone_t *zone) {
	isc_mem_t *mctx = NULL;

	REQUIRE(DNS_ZONE_VALID(zone));
	REQUIRE(isc_refcount_current(&zone->erefs) == 0);
	REQUIRE(zone->irefs == 0);
	REQUIRE(!LOCKED_ZONE(zone));
	REQUIRE(zone->timer == NULL);

	/*
	 * Managed objects.  Order is important.
	 */
	if (zone->request != NULL)
		dns_request_destroy(&zone->request); /* XXXMPA */
	INSIST(zone->readio == NULL);
	INSIST(zone->statelist == NULL);

	if (zone->task != NULL)
		isc_task_detach(&zone->task);
	if (zone->zmgr)
		dns_zonemgr_releasezone(zone->zmgr, zone);

	/* Unmanaged objects */
	if (zone->masterfile != NULL)
		isc_mem_free(zone->mctx, zone->masterfile);
	zone->masterfile = NULL;
	zone->journalsize = -1;
	if (zone->journal != NULL)
		isc_mem_free(zone->mctx, zone->journal);
	zone->journal = NULL;
	if (zone->counters != NULL)
		dns_stats_freecounters(zone->mctx, &zone->counters);
	if (zone->db != NULL)
		dns_db_detach(&zone->db);
	zone_freedbargs(zone);
	dns_zone_setmasterswithkeys(zone, NULL, NULL, 0);
	dns_zone_setalsonotify(zone, NULL, 0);
	zone->check_names = dns_severity_ignore;
	if (zone->update_acl != NULL)
		dns_acl_detach(&zone->update_acl);
	if (zone->forward_acl != NULL)
		dns_acl_detach(&zone->forward_acl);
	if (zone->notify_acl != NULL)
		dns_acl_detach(&zone->notify_acl);
	if (zone->query_acl != NULL)
		dns_acl_detach(&zone->query_acl);
	if (zone->xfr_acl != NULL)
		dns_acl_detach(&zone->xfr_acl);
	if (dns_name_dynamic(&zone->origin))
		dns_name_free(&zone->origin, zone->mctx);
	if (zone->ssutable != NULL)
		dns_ssutable_detach(&zone->ssutable);

	/* last stuff */
	DESTROYLOCK(&zone->lock);
	isc_refcount_destroy(&zone->erefs);
	zone->magic = 0;
	mctx = zone->mctx;
	isc_mem_put(mctx, zone, sizeof *zone);
	isc_mem_detach(&mctx);
}

/*
 *	Single shot.
 */
void
dns_zone_setclass(dns_zone_t *zone, dns_rdataclass_t rdclass) {

	REQUIRE(DNS_ZONE_VALID(zone));
	REQUIRE(rdclass != dns_rdataclass_none);

	/*
	 * Test and set.
	 */
	LOCK_ZONE(zone);
	REQUIRE(zone->rdclass == dns_rdataclass_none ||
		zone->rdclass == rdclass);
	zone->rdclass = rdclass;
	UNLOCK_ZONE(zone);
}

dns_rdataclass_t
dns_zone_getclass(dns_zone_t *zone){
	REQUIRE(DNS_ZONE_VALID(zone));

	return (zone->rdclass);
}

void
dns_zone_setnotifytype(dns_zone_t *zone, dns_notifytype_t notifytype) {
	REQUIRE(DNS_ZONE_VALID(zone));

	LOCK_ZONE(zone);
	zone->notifytype = notifytype;
	UNLOCK_ZONE(zone);
}

/*
 *	Single shot.
 */
void
dns_zone_settype(dns_zone_t *zone, dns_zonetype_t type) {

	REQUIRE(DNS_ZONE_VALID(zone));
	REQUIRE(type != dns_zone_none);

	/*
	 * Test and set.
	 */
	LOCK_ZONE(zone);
	REQUIRE(zone->type == dns_zone_none || zone->type == type);
	zone->type = type;
	UNLOCK_ZONE(zone);
}

static void
zone_freedbargs(dns_zone_t *zone) {
	unsigned int i;

	/* Free the old database argument list. */
	if (zone->db_argv != NULL) {
		for (i = 0; i < zone->db_argc; i++)
			isc_mem_free(zone->mctx, zone->db_argv[i]);
		isc_mem_put(zone->mctx, zone->db_argv,
			    zone->db_argc * sizeof *zone->db_argv);
	}
	zone->db_argc = 0;
	zone->db_argv = NULL;
}

isc_result_t
dns_zone_setdbtype(dns_zone_t *zone,
		   unsigned int dbargc, const char * const *dbargv) {
	isc_result_t result = ISC_R_SUCCESS;
	char **new = NULL;
	unsigned int i;

	REQUIRE(DNS_ZONE_VALID(zone));
	REQUIRE(dbargc >= 1);
	REQUIRE(dbargv != NULL);

	LOCK_ZONE(zone);

	/* Set up a new database argument list. */
	new = isc_mem_get(zone->mctx, dbargc * sizeof *new);
	if (new == NULL)
		goto nomem;
	for (i = 0; i < dbargc; i++)
		new[i] = NULL;
	for (i = 0; i < dbargc; i++) {
		new[i] = isc_mem_strdup(zone->mctx, dbargv[i]);
		if (new[i] == NULL)
			goto nomem;
	}

	/* Free the old list. */
	zone_freedbargs(zone);

	zone->db_argc = dbargc;
	zone->db_argv = new;
	result = ISC_R_SUCCESS;
	goto unlock;
	
 nomem:
	if (new != NULL) {
		for (i = 0; i < dbargc; i++) {
			if (zone->db_argv[i] != NULL)
				isc_mem_free(zone->mctx, new[i]);
			isc_mem_put(zone->mctx, new, 
				    dbargc * sizeof *new);
		}
	}
	result = ISC_R_NOMEMORY;
	
 unlock:
	UNLOCK_ZONE(zone);
	return (result);
}

void
dns_zone_setview(dns_zone_t *zone, dns_view_t *view) {
	REQUIRE(DNS_ZONE_VALID(zone));

	LOCK_ZONE(zone);
	if (zone->view != NULL)
		dns_view_weakdetach(&zone->view);
	dns_view_weakattach(view, &zone->view);
	UNLOCK_ZONE(zone);
}


dns_view_t *
dns_zone_getview(dns_zone_t *zone) {
	REQUIRE(DNS_ZONE_VALID(zone));

	return (zone->view);
}


isc_result_t
dns_zone_setorigin(dns_zone_t *zone, dns_name_t *origin) {
	isc_result_t result;

	REQUIRE(DNS_ZONE_VALID(zone));
	REQUIRE(origin != NULL);

	LOCK_ZONE(zone);
	if (dns_name_dynamic(&zone->origin)) {
		dns_name_free(&zone->origin, zone->mctx);
		dns_name_init(&zone->origin, NULL);
	}
	result = dns_name_dup(origin, zone->mctx, &zone->origin);
	UNLOCK_ZONE(zone);
	return (result);
}

	
static isc_result_t
dns_zone_setstring(dns_zone_t *zone, char **field, const char *value) {
	char *copy;

	if (value != NULL) {
		copy = isc_mem_strdup(zone->mctx, value);
		if (copy == NULL)
			return (ISC_R_NOMEMORY);
	} else {
		copy = NULL;
	}

	if (*field != NULL)
		isc_mem_free(zone->mctx, *field);

	*field = copy;
	return (ISC_R_SUCCESS);
}	

isc_result_t
dns_zone_setfile(dns_zone_t *zone, const char *file) {
	isc_result_t result = ISC_R_SUCCESS;

	REQUIRE(DNS_ZONE_VALID(zone));

	LOCK_ZONE(zone);
	result = dns_zone_setstring(zone, &zone->masterfile, file);
	if (result == ISC_R_SUCCESS)
		result = default_journal(zone);
	UNLOCK_ZONE(zone);

	return (result);
}

const char *
dns_zone_getfile(dns_zone_t *zone) {
	REQUIRE(DNS_ZONE_VALID(zone));

	return (zone->masterfile);
}

static isc_result_t
default_journal(dns_zone_t *zone) {
	isc_result_t result;
	char *journal;

	REQUIRE(DNS_ZONE_VALID(zone));
	REQUIRE(LOCKED_ZONE(zone));

	if (zone->masterfile != NULL) {
		/* Calculate string length including '\0'. */
		int len = strlen(zone->masterfile) + sizeof ".jnl";
		journal = isc_mem_allocate(zone->mctx, len);
		if (journal == NULL)
			return (ISC_R_NOMEMORY);
		strcpy(journal, zone->masterfile);
		strcat(journal, ".jnl");
	} else {
		journal = NULL;
	}
	result = dns_zone_setstring(zone, &zone->journal, journal);
	if (journal != NULL)
		isc_mem_free(zone->mctx, journal);
	return (result);
}

isc_result_t
dns_zone_setjournal(dns_zone_t *zone, const char *journal) {
	isc_result_t result = ISC_R_SUCCESS;

	REQUIRE(DNS_ZONE_VALID(zone));

	LOCK_ZONE(zone);
	result = dns_zone_setstring(zone, &zone->journal, journal);	
	UNLOCK_ZONE(zone);

	return (result);
}

char *
dns_zone_getjournal(dns_zone_t *zone) {
	REQUIRE(DNS_ZONE_VALID(zone));

	return (zone->journal);
}

/*
 * Return true iff the zone is "dynamic", in the sense that the zone's
 * master file (if any) is written by the server, rather than being
 * updated manually and read by the server.
 *
 * This is true for slave zones, stub zones, and zones that allow
 * dynamic updates either by having an update policy ("ssutable")
 * or an "allow-update" ACL with a value other than exactly "{ none; }".
 */
static isc_boolean_t
zone_isdynamic(dns_zone_t *zone) {
	REQUIRE(DNS_ZONE_VALID(zone));

	return (ISC_TF(zone->type == dns_zone_slave ||
		       zone->type == dns_zone_stub ||
		       zone->ssutable != NULL ||
		       (zone->update_acl != NULL &&
			! (zone->update_acl->length == 1 && 
			   zone->update_acl->elements[0].negative == ISC_TRUE
			   &&
			   zone->update_acl->elements[0].type ==
			   dns_aclelementtype_any))));
}


static isc_result_t
zone_load(dns_zone_t *zone, unsigned int flags) {
	isc_result_t result;
	isc_time_t now;
	isc_time_t loadtime, filetime;
	dns_db_t *db = NULL;

	REQUIRE(DNS_ZONE_VALID(zone));

	LOCK_ZONE(zone);
	isc_time_now(&now);

	INSIST(zone->type != dns_zone_none);

	if (DNS_ZONE_FLAG(zone, DNS_ZONEFLG_LOADING)) {
		result = ISC_R_SUCCESS;
		goto cleanup;
	}

	if (zone->db != NULL && zone->masterfile == NULL) {
		/*
		 * The zone has no master file configured, but it already
		 * has a database.  It could be the built-in
		 * version.bind. CH zone, a zone with a persistent
		 * database being reloaded, or maybe a zone that
		 * used to have a master file but whose configuration
		 * was changed so that it no longer has one.  Do nothing.
		 */
		result = ISC_R_SUCCESS;
		goto cleanup;
	}

	if (zone->db != NULL && zone_isdynamic(zone)) {
		/*
		 * This is a slave, stub, or dynamically updated
		 * zone being reloaded.  Do nothing - the database
		 * we already have is guaranteed to be up-to-date.
		 */
		result = ISC_R_SUCCESS;
		goto cleanup;
	}
		
	/*
	 * Don't do the load if the file that stores the zone is older
	 * than the last time the zone was loaded.  If the zone has not
	 * been loaded yet, zone->loadtime will be the epoch.
	 */
	if (zone->masterfile != NULL && ! isc_time_isepoch(&zone->loadtime)) {
		/*
		 * The file is already loaded.  If we are just doing a
		 * "rndc reconfig", we are done.
		 */
		if ((flags & DNS_ZONELOADFLAG_NOSTAT) != 0) {
			result = ISC_R_SUCCESS;
			goto cleanup;
		}
		if (! DNS_ZONE_FLAG(zone, DNS_ZONEFLG_HASINCLUDE)) {
			result = isc_file_getmodtime(zone->masterfile,
						     &filetime);
			if (result == ISC_R_SUCCESS &&
			    isc_time_compare(&filetime, &zone->loadtime) < 0) {
				dns_zone_log(zone, ISC_LOG_DEBUG(1),
					     "skipping load: master file older "
					     "than last load");
				result = ISC_R_SUCCESS;
				goto cleanup;
			}
		}
	} 

	INSIST(zone->db_argc >= 1);

	if ((zone->type == dns_zone_slave || zone->type == dns_zone_stub) &&
	    (strcmp(zone->db_argv[0], "rbt") == 0 ||
	     strcmp(zone->db_argv[0], "rbt64") == 0)) {
		if (zone->masterfile == NULL ||
		    !isc_file_exists(zone->masterfile)) {
			if (zone->masterfile != NULL)
				dns_zone_log(zone, ISC_LOG_DEBUG(1),
					     "no master file");
			zone->refreshtime = now;
			if (zone->task != NULL)
				zone_settimer(zone, &now);
			result = ISC_R_SUCCESS;
			goto cleanup;
		}
	}

	dns_zone_log(zone, ISC_LOG_DEBUG(1), "starting load");

	/*
	 * Store the current time before the zone is loaded, so that if the
	 * file changes between the time of the load and the time that
	 * zone->loadtime is set, then the file will still be reloaded
	 * the next time dns_zone_load is called.
	 */
	result = isc_time_now(&loadtime);
	if (result != ISC_R_SUCCESS)
		goto cleanup;

	result = dns_db_create(zone->mctx, zone->db_argv[0],
			       &zone->origin, (zone->type == dns_zone_stub) ?
			       dns_dbtype_stub : dns_dbtype_zone,
			       zone->rdclass,
			       zone->db_argc - 1, zone->db_argv + 1,
			       &db);

	if (result != ISC_R_SUCCESS) {
		dns_zone_log(zone, ISC_LOG_ERROR,
			     "loading zone: creating database: %s",
			     isc_result_totext(result));
		goto cleanup;
	}

	if (! dns_db_ispersistent(db)) {
		if (zone->masterfile != NULL) {
			result = zone_startload(db, zone, loadtime);
		} else {
			result = DNS_R_NOMASTERFILE;
			if (zone->type == dns_zone_master) {
				dns_zone_log(zone, ISC_LOG_ERROR,
					     "loading zone: "
					     "no master file configured");
				goto cleanup;
			}
			dns_zone_log(zone, ISC_LOG_INFO, "loading zone: "
				     "no master file configured: continuing");
		}
	}

	if (result == DNS_R_CONTINUE) {
		DNS_ZONE_SETFLAG(zone, DNS_ZONEFLG_LOADING);
		result = ISC_R_SUCCESS;
		goto cleanup;
	}

	result = zone_postload(zone, db, loadtime, result);

 cleanup:
	UNLOCK_ZONE(zone);
	if (db != NULL)
		dns_db_detach(&db);
	return (result);
}

isc_result_t
dns_zone_load(dns_zone_t *zone) {
	return (zone_load(zone, 0));
}

isc_result_t
dns_zone_loadnew(dns_zone_t *zone) {
	return (zone_load(zone, DNS_ZONELOADFLAG_NOSTAT));
}

static void
zone_gotreadhandle(isc_task_t *task, isc_event_t *event) {
	dns_load_t *load = event->ev_arg;
	isc_result_t result = ISC_R_SUCCESS;
	unsigned int options;

	REQUIRE(DNS_LOAD_VALID(load));

	if ((event->ev_attributes & ISC_EVENTATTR_CANCELED) != 0)
		result = ISC_R_CANCELED;
	isc_event_free(&event);
	if (result == ISC_R_CANCELED)
		goto fail;

	options = DNS_MASTER_ZONE;
	if (load->zone->type == dns_zone_slave)
		options |= DNS_MASTER_SLAVE;