sdb.c

bind-3.2.

destroy(dns_sdb_t *sdb) {
	isc_mem_t *mctx;
	dns_sdbimplementation_t *imp = sdb->implementation;

	mctx = sdb->common.mctx;

	if (imp->methods->destroy != NULL) {
		MAYBE_LOCK(sdb);
		imp->methods->destroy(sdb->zone, imp->driverdata,
				      &sdb->dbdata);
		MAYBE_UNLOCK(sdb);
	}

	isc_mem_free(mctx, sdb->zone);
	DESTROYLOCK(&sdb->lock);

	sdb->common.magic = 0;
	sdb->common.impmagic = 0;

	dns_name_free(&sdb->common.origin, mctx);

	isc_mem_put(mctx, sdb, sizeof(dns_sdb_t));
	isc_mem_detach(&mctx);
}

static void
detach(dns_db_t **dbp) {
	dns_sdb_t *sdb = (dns_sdb_t *)(*dbp);
	isc_boolean_t need_destroy = ISC_FALSE;

	REQUIRE(VALID_SDB(sdb));
	LOCK(&sdb->lock);
	REQUIRE(sdb->references > 0);
	sdb->references--;
	if (sdb->references == 0)
		need_destroy = ISC_TRUE;
	UNLOCK(&sdb->lock);

	if (need_destroy)
		destroy(sdb);

	*dbp = NULL;
}

static isc_result_t
beginload(dns_db_t *db, dns_addrdatasetfunc_t *addp, dns_dbload_t **dbloadp) {
	UNUSED(db);
	UNUSED(addp);
	UNUSED(dbloadp);
	return (ISC_R_NOTIMPLEMENTED);
}

static isc_result_t
endload(dns_db_t *db, dns_dbload_t **dbloadp) {
	UNUSED(db);
	UNUSED(dbloadp);
	return (ISC_R_NOTIMPLEMENTED);
}

static isc_result_t
dump(dns_db_t *db, dns_dbversion_t *version, const char *filename) {
	UNUSED(db);
	UNUSED(version);
	UNUSED(filename);
	return (ISC_R_NOTIMPLEMENTED);
}

static void
currentversion(dns_db_t *db, dns_dbversion_t **versionp) {
	REQUIRE(versionp != NULL && *versionp == NULL);

	UNUSED(db);

	*versionp = (void *) &dummy;
	return;
}

static isc_result_t
newversion(dns_db_t *db, dns_dbversion_t **versionp) {
	UNUSED(db);
	UNUSED(versionp);

	return (ISC_R_NOTIMPLEMENTED);
}

static void
attachversion(dns_db_t *db, dns_dbversion_t *source, 
	      dns_dbversion_t **targetp)
{
	REQUIRE(source != NULL && source == (void *) &dummy);

	UNUSED(db);
	UNUSED(source);
	UNUSED(targetp);
	return;
}

static void
closeversion(dns_db_t *db, dns_dbversion_t **versionp, isc_boolean_t commit) {
	REQUIRE(versionp != NULL && *versionp == (void *) &dummy);
	REQUIRE(commit == ISC_FALSE);

	UNUSED(db);
	UNUSED(commit);

	*versionp = NULL;
}

static isc_result_t
createnode(dns_sdb_t *sdb, dns_sdbnode_t **nodep) {
	dns_sdbnode_t *node;
	isc_result_t result;

	node = isc_mem_get(sdb->common.mctx, sizeof(dns_sdbnode_t));
	if (node == NULL)
		return (ISC_R_NOMEMORY);

	node->sdb = NULL;
	attach((dns_db_t *)sdb, (dns_db_t **)&node->sdb);
	ISC_LIST_INIT(node->lists);
	ISC_LIST_INIT(node->buffers);
	ISC_LINK_INIT(node, link);
	node->name = NULL;
	result = isc_mutex_init(&node->lock);
	if (result != ISC_R_SUCCESS) {
		UNEXPECTED_ERROR(__FILE__, __LINE__,
				 "isc_mutex_init() failed: %s",
				 isc_result_totext(result));
		isc_mem_put(sdb->common.mctx, node, sizeof(dns_sdbnode_t));
		return (ISC_R_UNEXPECTED);
	}
	dns_rdatacallbacks_init(&node->callbacks);
	node->references = 1;
	node->magic = SDBLOOKUP_MAGIC;

	*nodep = node;
	return (ISC_R_SUCCESS);
}

static void
destroynode(dns_sdbnode_t *node) {
	dns_rdatalist_t *list;
	dns_rdata_t *rdata;
	isc_buffer_t *b;
	dns_sdb_t *sdb;
	isc_mem_t *mctx;

	sdb = node->sdb;
	mctx = sdb->common.mctx;

	while (!ISC_LIST_EMPTY(node->lists)) {
		list = ISC_LIST_HEAD(node->lists);
		while (!ISC_LIST_EMPTY(list->rdata)) {
			rdata = ISC_LIST_HEAD(list->rdata);
			ISC_LIST_UNLINK(list->rdata, rdata, link);
			isc_mem_put(mctx, rdata, sizeof(dns_rdata_t));
		}
		ISC_LIST_UNLINK(node->lists, list, link);
		isc_mem_put(mctx, list, sizeof(dns_rdatalist_t));
	}

	while (!ISC_LIST_EMPTY(node->buffers)) {
		b = ISC_LIST_HEAD(node->buffers);
		ISC_LIST_UNLINK(node->buffers, b, link);
		isc_buffer_free(&b);
	}

	if (node->name != NULL) {
		dns_name_free(node->name, mctx);
		isc_mem_put(mctx, node->name, sizeof(dns_name_t));
	}
	DESTROYLOCK(&node->lock);
	node->magic = 0;
	isc_mem_put(mctx, node, sizeof(dns_sdbnode_t));
	detach((dns_db_t **)&sdb);
}

static isc_result_t
findnode(dns_db_t *db, dns_name_t *name, isc_boolean_t create,
	 dns_dbnode_t **nodep)
{
	dns_sdb_t *sdb = (dns_sdb_t *)db;
	dns_sdbnode_t *node = NULL;
	isc_result_t result;
	isc_buffer_t b;
	char namestr[DNS_NAME_MAXTEXT + 1];
	isc_boolean_t isorigin;
	dns_sdbimplementation_t *imp;

	REQUIRE(VALID_SDB(sdb));
	REQUIRE(create == ISC_FALSE);
	REQUIRE(nodep != NULL && *nodep == NULL);

	UNUSED(name);
	UNUSED(create);

	imp = sdb->implementation;

	isc_buffer_init(&b, namestr, sizeof(namestr));
	if ((imp->flags & DNS_SDBFLAG_RELATIVEOWNER) != 0) {
		dns_name_t relname;
		unsigned int labels;

		labels = dns_name_countlabels(name) -
			 dns_name_countlabels(&db->origin);
		dns_name_init(&relname, NULL);
		dns_name_getlabelsequence(name, 0, labels, &relname);
		result = dns_name_totext(&relname, ISC_TRUE, &b);
		if (result != ISC_R_SUCCESS)
			return (result);
	} else {
		result = dns_name_totext(name, ISC_TRUE, &b);
		if (result != ISC_R_SUCCESS)
			return (result);
	}
	isc_buffer_putuint8(&b, 0);

	result = createnode(sdb, &node);
	if (result != ISC_R_SUCCESS)
		return (result);

	isorigin = dns_name_equal(name, &sdb->common.origin);

	MAYBE_LOCK(sdb);
	result = imp->methods->lookup(sdb->zone, namestr, sdb->dbdata, node);
	MAYBE_UNLOCK(sdb);
	if (result != ISC_R_SUCCESS && !isorigin) {
		destroynode(node);
		return (result);
	}

	if (isorigin && imp->methods->authority != NULL) {
		MAYBE_LOCK(sdb);
		result = imp->methods->authority(sdb->zone, sdb->dbdata, node);
		MAYBE_UNLOCK(sdb);
		if (result != ISC_R_SUCCESS) {
			destroynode(node);
			return (result);
		}
	}
	
	*nodep = node;
	return (ISC_R_SUCCESS);
}

static isc_result_t
find(dns_db_t *db, dns_name_t *name, dns_dbversion_t *version,
     dns_rdatatype_t type, unsigned int options, isc_stdtime_t now,
     dns_dbnode_t **nodep, dns_name_t *foundname,
     dns_rdataset_t *rdataset, dns_rdataset_t *sigrdataset)
{
	dns_sdb_t *sdb = (dns_sdb_t *)db;
	dns_dbnode_t *node = NULL;
	dns_fixedname_t fname;
	dns_rdataset_t xrdataset;
	dns_name_t *xname;
	unsigned int nlabels, olabels;
	isc_result_t result;
	unsigned int i;

	REQUIRE(VALID_SDB(sdb));
	REQUIRE(nodep == NULL || *nodep == NULL);
	REQUIRE(version == NULL || version == (void *) &dummy);

	UNUSED(options);
	UNUSED(sdb);

	if (!dns_name_issubdomain(name, &db->origin))
		return (DNS_R_NXDOMAIN);

	olabels = dns_name_countlabels(&db->origin);
	nlabels = dns_name_countlabels(name);

	dns_fixedname_init(&fname);
	xname = dns_fixedname_name(&fname);

	if (rdataset == NULL) {
		dns_rdataset_init(&xrdataset);
		rdataset = &xrdataset;
	}

	result = DNS_R_NXDOMAIN;

	for (i = olabels; i <= nlabels; i++) {
		/*
		 * Unless this is an explicit lookup at the origin, don't
		 * look at the origin.
		 */
		if (i == olabels && i != nlabels)
			continue;

		/*
		 * Look up the next label.
		 */
		dns_name_getlabelsequence(name, nlabels - i, i, xname);
		result = findnode(db, xname, ISC_FALSE, &node);
		if (result != ISC_R_SUCCESS) {
			result = DNS_R_NXDOMAIN;
			continue;
		}

		/*
		 * Look for a DNAME at the current label, unless this is
		 * the qname.
		 */
		if (i < nlabels) {
			result = findrdataset(db, node, version,
					      dns_rdatatype_dname,
					      0, now, rdataset, sigrdataset);
			if (result == ISC_R_SUCCESS) {
				result = DNS_R_DNAME;
				break;
			}
		}

		/*
		 * Look for an NS at the current label, unless this is the
		 * origin or glue is ok.
		 */
		if (i != olabels && (options & DNS_DBFIND_GLUEOK) == 0) {
			result = findrdataset(db, node, version,
					      dns_rdatatype_ns,
					      0, now, rdataset, sigrdataset);
			if (result == ISC_R_SUCCESS) {
				if (i == nlabels && type == dns_rdatatype_any)
				{
					result = DNS_R_ZONECUT;
					dns_rdataset_disassociate(rdataset);
					if (sigrdataset != NULL)
						dns_rdataset_disassociate
								(sigrdataset);
				} else
					result = DNS_R_DELEGATION;
				break;
			}
		}

		/*
		 * If the current name is not the qname, add another label
		 * and try again.
		 */
		if (i < nlabels) {
			destroynode(node);
			node = NULL;
			continue;
		}

		/*
		 * If we're looking for ANY, we're done.
		 */
		if (type == dns_rdatatype_any) {
			result = ISC_R_SUCCESS;
			break;
		}

		/*
		 * Look for the qtype.
		 */
		result = findrdataset(db, node, version, type,
				      0, now, rdataset, sigrdataset);
		if (result == ISC_R_SUCCESS)
			break;

		/*
		 * Look for a CNAME
		 */
		if (type != dns_rdatatype_cname) {
			result = findrdataset(db, node, version,
					      dns_rdatatype_cname,
					      0, now, rdataset, sigrdataset);
			if (result == ISC_R_SUCCESS) {
				result = DNS_R_CNAME;
				break;
			}
		}

		result = DNS_R_NXRRSET;
		break;
	}

	if (rdataset == &xrdataset && dns_rdataset_isassociated(rdataset))
		dns_rdataset_disassociate(rdataset);

	if (foundname != NULL) {
		isc_result_t xresult;

		xresult = dns_name_copy(xname, foundname, NULL);
		if (xresult != ISC_R_SUCCESS) {
			destroynode(node);
			if (dns_rdataset_isassociated(rdataset))
				dns_rdataset_disassociate(rdataset);
			return (DNS_R_BADDB);
		}
	}

	if (nodep != NULL)
		*nodep = node;
	else if (node != NULL)
		detachnode(db, &node);

	return (result);
}

static isc_result_t
findzonecut(dns_db_t *db, dns_name_t *name, unsigned int options,
	    isc_stdtime_t now, dns_dbnode_t **nodep, dns_name_t *foundname,
	    dns_rdataset_t *rdataset, dns_rdataset_t *sigrdataset)
{
	UNUSED(db);
	UNUSED(name);
	UNUSED(options);
	UNUSED(now);
	UNUSED(nodep);
	UNUSED(foundname);
	UNUSED(rdataset);
	UNUSED(sigrdataset);

	return (ISC_R_NOTIMPLEMENTED);
}

static void
attachnode(dns_db_t *db, dns_dbnode_t *source, dns_dbnode_t **targetp) {
	dns_sdb_t *sdb = (dns_sdb_t *)db;
	dns_sdbnode_t *node = (dns_sdbnode_t *)source;

	REQUIRE(VALID_SDB(sdb));

	UNUSED(sdb);

	LOCK(&node->lock);
	INSIST(node->references > 0);
	node->references++;
	INSIST(node->references != 0);		/* Catch overflow. */
	UNLOCK(&node->lock);

	*targetp = source;
}

static void
detachnode(dns_db_t *db, dns_dbnode_t **targetp) {
	dns_sdb_t *sdb = (dns_sdb_t *)db;
	dns_sdbnode_t *node;
	isc_boolean_t need_destroy = ISC_FALSE;

	REQUIRE(VALID_SDB(sdb));
	REQUIRE(targetp != NULL && *targetp != NULL);

	UNUSED(sdb);

	node = (dns_sdbnode_t *)(*targetp);

	LOCK(&node->lock);
	INSIST(node->references > 0);
	node->references--;
	if (node->references == 0)
		need_destroy = ISC_TRUE;
	UNLOCK(&node->lock);

	if (need_destroy)
		destroynode(node);

	*targetp = NULL;
}

static isc_result_t
expirenode(dns_db_t *db, dns_dbnode_t *node, isc_stdtime_t now) {
	UNUSED(db);
	UNUSED(node);
	UNUSED(now);
	INSIST(0);
	return (ISC_R_UNEXPECTED);
}

static void
printnode(dns_db_t *db, dns_dbnode_t *node, FILE *out) {
	UNUSED(db);
	UNUSED(node);
	UNUSED(out);
	return;
}

static isc_result_t
createiterator(dns_db_t *db, isc_boolean_t relative_names,
	       dns_dbiterator_t **iteratorp)
{
	dns_sdb_t *sdb = (dns_sdb_t *)db;
	sdb_dbiterator_t *sdbiter;
	dns_sdbimplementation_t *imp = sdb->implementation;
	isc_result_t result;