zone.c

非常好的dns解析软件

static void zone_maintenance(dns_zone_t *zone);
static void zone_notify(dns_zone_t *zone, isc_time_t *now);
static void dump_done(void *arg, isc_result_t result);

#define ENTER zone_debuglog(zone, me, 1, "enter")

static const unsigned int dbargc_default = 1;
static const char *dbargv_default[] = { "rbt" };

#define DNS_ZONE_JITTER_ADD(a, b, c) \
	do { \
		isc_interval_t _i; \
		isc_uint32_t _j; \
		_j = isc_random_jitter((b), (b)/4); \
		isc_interval_set(&_i, _j, 0); \
		if (isc_time_add((a), &_i, (c)) != ISC_R_SUCCESS) { \
			dns_zone_log(zone, ISC_LOG_WARNING, \
				     "epoch approaching: upgrade required: " \
				     "now + %s failed", #b); \
			isc_interval_set(&_i, _j/2, 0); \
			(void)isc_time_add((a), &_i, (c)); \
		} \
	} while (0)

#define DNS_ZONE_TIME_ADD(a, b, c) \
	do { \
		isc_interval_t _i; \
		isc_interval_set(&_i, (b), 0); \
		if (isc_time_add((a), &_i, (c)) != ISC_R_SUCCESS) { \
			dns_zone_log(zone, ISC_LOG_WARNING, \
				     "epoch approaching: upgrade required: " \
				     "now + %s failed", #b); \
			isc_interval_set(&_i, (b)/2, 0); \
			(void)isc_time_add((a), &_i, (c)); \
		} \
	} while (0)

/***
 ***	Public functions.
 ***/

isc_result_t
dns_zone_create(dns_zone_t **zonep, isc_mem_t *mctx) {
	isc_result_t result;
	dns_zone_t *zone;
	isc_time_t now;

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

	TIME_NOW(&now);
	zone = isc_mem_get(mctx, sizeof(*zone));
	if (zone == NULL)
		return (ISC_R_NOMEMORY);

	zone->mctx = NULL;
	isc_mem_attach(mctx, &zone->mctx);

	result = isc_mutex_init(&zone->lock);
	if (result != ISC_R_SUCCESS)
		goto free_zone;

	result = ZONEDB_INITLOCK(&zone->dblock);
	if (result != ISC_R_SUCCESS)
		goto free_mutex;

	/* XXX MPA check that all elements are initialised */
#ifdef DNS_ZONE_CHECKLOCK
	zone->locked = ISC_FALSE;
#endif
	zone->db = NULL;
	zone->zmgr = NULL;
	ISC_LINK_INIT(zone, link);
	result = isc_refcount_init(&zone->erefs, 1);	/* Implicit attach. */
	if (result != ISC_R_SUCCESS)
		goto free_dblock;
	zone->irefs = 0;
	dns_name_init(&zone->origin, NULL);
	zone->masterfile = NULL;
	zone->masterformat =  dns_masterformat_none;
	zone->keydirectory = NULL;
	zone->journalsize = -1;
	zone->journal = NULL;
	zone->rdclass = dns_rdataclass_none;
	zone->type = dns_zone_none;
	zone->flags = 0;
	zone->options = 0;
	zone->db_argc = 0;
	zone->db_argv = NULL;
	isc_time_settoepoch(&zone->expiretime);
	isc_time_settoepoch(&zone->refreshtime);
	isc_time_settoepoch(&zone->dumptime);
	isc_time_settoepoch(&zone->loadtime);
	zone->notifytime = now;
	zone->serial = 0;
	zone->refresh = DNS_ZONE_DEFAULTREFRESH;
	zone->retry = DNS_ZONE_DEFAULTRETRY;
	zone->expire = 0;
	zone->minimum = 0;
	zone->maxrefresh = DNS_ZONE_MAXREFRESH;
	zone->minrefresh = DNS_ZONE_MINREFRESH;
	zone->maxretry = DNS_ZONE_MAXRETRY;
	zone->minretry = DNS_ZONE_MINRETRY;
	zone->masters = NULL;
	zone->masterkeynames = NULL;
	zone->mastersok = NULL;
	zone->masterscnt = 0;
	zone->curmaster = 0;
	zone->notify = NULL;
	zone->notifytype = dns_notifytype_yes;
	zone->notifycnt = 0;
	zone->task = NULL;
	zone->update_acl = NULL;
	zone->forward_acl = NULL;
	zone->notify_acl = NULL;
	zone->query_acl = NULL;
	zone->xfr_acl = NULL;
	zone->update_disabled = ISC_FALSE;
	zone->zero_no_soa_ttl = ISC_TRUE;
	zone->check_names = dns_severity_ignore;
	zone->request = NULL;
	zone->lctx = NULL;
	zone->readio = NULL;
	zone->dctx = NULL;
	zone->writeio = NULL;
	zone->timer = NULL;
	zone->idlein = DNS_DEFAULT_IDLEIN;
	zone->idleout = DNS_DEFAULT_IDLEOUT;
	ISC_LIST_INIT(zone->notifies);
	isc_sockaddr_any(&zone->notifysrc4);
	isc_sockaddr_any6(&zone->notifysrc6);
	isc_sockaddr_any(&zone->xfrsource4);
	isc_sockaddr_any6(&zone->xfrsource6);
	isc_sockaddr_any(&zone->altxfrsource4);
	isc_sockaddr_any6(&zone->altxfrsource6);
	zone->xfr = NULL;
	zone->tsigkey = NULL;
	zone->maxxfrin = MAX_XFER_TIME;
	zone->maxxfrout = MAX_XFER_TIME;
	zone->ssutable = NULL;
	zone->sigvalidityinterval = 30 * 24 * 3600;
	zone->view = NULL;
	zone->acache = NULL;
	zone->checkmx = NULL;
	zone->checksrv = NULL;
	zone->checkns = NULL;
	ISC_LINK_INIT(zone, statelink);
	zone->statelist = NULL;
	zone->counters = NULL;
	zone->notifydelay = 5;
	zone->isself = NULL;
	zone->isselfarg = 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_erefs;

	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_erefs:
	isc_refcount_decrement(&zone->erefs, NULL);
	isc_refcount_destroy(&zone->erefs);

 free_dblock:
	ZONEDB_DESTROYLOCK(&zone->dblock);

 free_mutex:
	DESTROYLOCK(&zone->lock);

 free_zone:
	isc_mem_putanddetach(&zone->mctx, zone, sizeof(*zone));
	return (result);
}

/*
 * 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);
	INSIST(zone->writeio == 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;
	if (zone->keydirectory != NULL)
		isc_mem_free(zone->mctx, zone->keydirectory);
	zone->keydirectory = 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)
		zone_detachdb(zone);
	if (zone->acache != NULL)
		dns_acache_detach(&zone->acache);
	zone_freedbargs(zone);
	RUNTIME_CHECK(dns_zone_setmasterswithkeys(zone, NULL, NULL, 0)
		      == ISC_R_SUCCESS);
	RUNTIME_CHECK(dns_zone_setalsonotify(zone, NULL, 0)
		      == ISC_R_SUCCESS);
	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 */
	ZONEDB_DESTROYLOCK(&zone->dblock);
	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_getdbtype(dns_zone_t *zone, char ***argv, isc_mem_t *mctx) {
	size_t size = 0;
	unsigned int i;
	isc_result_t result = ISC_R_SUCCESS;
	void *mem;
	char **tmp, *tmp2;
	
	REQUIRE(DNS_ZONE_VALID(zone));
	REQUIRE(argv != NULL && *argv == NULL);
	
	LOCK_ZONE(zone);
	size = (zone->db_argc + 1) * sizeof(char *);
	for (i = 0; i < zone->db_argc; i++)
		size += strlen(zone->db_argv[i]) + 1;
	mem = isc_mem_allocate(mctx, size);
	if (mem != NULL) {
		tmp = mem;
		tmp2 = mem;
		tmp2 += (zone->db_argc + 1) * sizeof(char *);
		for (i = 0; i < zone->db_argc; i++) {
			*tmp++ = tmp2;
			strcpy(tmp2, zone->db_argv[i]);
			tmp2 += strlen(tmp2) + 1;
		}
		*tmp = NULL;
	} else
		result = ISC_R_NOMEMORY;
	UNLOCK_ZONE(zone);
	*argv = mem;
	return (result);
}

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 (new[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, const 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);
}

void
dns_zone_setacache(dns_zone_t *zone, dns_acache_t *acache) {
	REQUIRE(DNS_ZONE_VALID(zone));
	REQUIRE(acache != NULL);
	
	LOCK_ZONE(zone);
	if (zone->acache != NULL)
		dns_acache_detach(&zone->acache);
	dns_acache_attach(acache, &zone->acache);
	ZONEDB_LOCK(&zone->dblock, isc_rwlocktype_read);
	if (zone->db != NULL) {
		isc_result_t result;

		/*
		 * If the zone reuses an existing DB, the DB needs to be
		 * set in the acache explicitly.  We can safely ignore the
		 * case where the DB is already set.  If other error happens,
		 * the acache will not work effectively.
		 */
		result = dns_acache_setdb(acache, zone->db);
		if (result != ISC_R_SUCCESS && result != ISC_R_EXISTS) {
			UNEXPECTED_ERROR(__FILE__, __LINE__,
					 "dns_acache_setdb() failed: %s",
					 isc_result_totext(result));
		}
	}
	ZONEDB_UNLOCK(&zone->dblock, isc_rwlocktype_read);
	UNLOCK_ZONE(zone);
}

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

	if (value != NULL) {