update.c

bind 9.3结合mysql数据库

				       client->mctx, inception, expire));
		} else {
			INSIST(0);
		}
	}

	/* Record our changes for the journal. */
	while ((t = ISC_LIST_HEAD(sig_diff.tuples)) != NULL) {
		ISC_LIST_UNLINK(sig_diff.tuples, t, link);
		dns_diff_appendminimal(diff, &t);
	}
	while ((t = ISC_LIST_HEAD(nsec_mindiff.tuples)) != NULL) {
		ISC_LIST_UNLINK(nsec_mindiff.tuples, t, link);
		dns_diff_appendminimal(diff, &t);
	}

	INSIST(ISC_LIST_EMPTY(sig_diff.tuples));
	INSIST(ISC_LIST_EMPTY(nsec_diff.tuples));
	INSIST(ISC_LIST_EMPTY(nsec_mindiff.tuples));

 failure:
	dns_diff_clear(&sig_diff);
	dns_diff_clear(&nsec_diff);
	dns_diff_clear(&nsec_mindiff);

	dns_diff_clear(&affected);
	dns_diff_clear(&diffnames);

	for (i = 0; i < nkeys; i++)
		dst_key_free(&zone_keys[i]);

	return (result);
}


/**************************************************************************/
/*
 * The actual update code in all its glory.  We try to follow
 * the RFC2136 pseudocode as closely as possible.
 */

static isc_result_t
send_update_event(ns_client_t *client, dns_zone_t *zone) {
	isc_result_t result = ISC_R_SUCCESS;
	update_event_t *event = NULL;
	isc_task_t *zonetask = NULL;
	ns_client_t *evclient;

	event = (update_event_t *)
		isc_event_allocate(client->mctx, client, DNS_EVENT_UPDATE,
				   update_action, NULL, sizeof(*event));
	if (event == NULL)
		FAIL(ISC_R_NOMEMORY);
	event->zone = zone;
	event->result = ISC_R_SUCCESS;

	evclient = NULL;
	ns_client_attach(client, &evclient);
	INSIST(client->nupdates == 0);
	client->nupdates++;
	event->ev_arg = evclient;

	dns_zone_gettask(zone, &zonetask);
	isc_task_send(zonetask, ISC_EVENT_PTR(&event));

 failure:
	if (event != NULL)
		isc_event_free(ISC_EVENT_PTR(&event));
	return (result);
}

static void
respond(ns_client_t *client, isc_result_t result) {
	isc_result_t msg_result;

	msg_result = dns_message_reply(client->message, ISC_TRUE);
	if (msg_result != ISC_R_SUCCESS)
		goto msg_failure;
	client->message->rcode = dns_result_torcode(result);

	ns_client_send(client);
	return;

 msg_failure:
	isc_log_write(ns_g_lctx, NS_LOGCATEGORY_UPDATE, NS_LOGMODULE_UPDATE,
		      ISC_LOG_ERROR,
		      "could not create update response message: %s",
		      isc_result_totext(msg_result));
	ns_client_next(client, msg_result);
}

void
ns_update_start(ns_client_t *client, isc_result_t sigresult) {
	dns_message_t *request = client->message;
	isc_result_t result;
	dns_name_t *zonename;
	dns_rdataset_t *zone_rdataset;
	dns_zone_t *zone = NULL;

	/*
	 * Interpret the zone section.
	 */
	result = dns_message_firstname(request, DNS_SECTION_ZONE);
	if (result != ISC_R_SUCCESS)
		FAILC(DNS_R_FORMERR,
		      "update zone section empty");

	/*
	 * The zone section must contain exactly one "question", and
	 * it must be of type SOA.
	 */
	zonename = NULL;
	dns_message_currentname(request, DNS_SECTION_ZONE, &zonename);
	zone_rdataset = ISC_LIST_HEAD(zonename->list);
	if (zone_rdataset->type != dns_rdatatype_soa)
		FAILC(DNS_R_FORMERR,
		      "update zone section contains non-SOA");
	if (ISC_LIST_NEXT(zone_rdataset, link) != NULL)
		FAILC(DNS_R_FORMERR,
		      "update zone section contains multiple RRs");

	/* The zone section must have exactly one name. */
	result = dns_message_nextname(request, DNS_SECTION_ZONE);
	if (result != ISC_R_NOMORE)
		FAILC(DNS_R_FORMERR,
		      "update zone section contains multiple RRs");

	result = dns_zt_find(client->view->zonetable, zonename, 0, NULL,
			     &zone);
	if (result != ISC_R_SUCCESS)
		FAILC(DNS_R_NOTAUTH,
		      "not authoritative for update zone");

	switch(dns_zone_gettype(zone)) {
	case dns_zone_master:
		/*
		 * We can now fail due to a bad signature as we now know
		 * that we are the master.
		 */
		if (sigresult != ISC_R_SUCCESS)
			FAIL(sigresult);
		CHECK(send_update_event(client, zone));
		break;
	case dns_zone_slave:
		CHECK(checkupdateacl(client, dns_zone_getforwardacl(zone),
				     "update forwarding", zonename, ISC_TRUE));
		CHECK(send_forward_event(client, zone));
		break;
	default:
		FAILC(DNS_R_NOTAUTH,
		      "not authoritative for update zone");
	}
	return;

 failure:
	/*
	 * We failed without having sent an update event to the zone.
	 * We are still in the client task context, so we can
	 * simply give an error response without switching tasks.
	 */
	respond(client, result);
	if (zone != NULL)
		dns_zone_detach(&zone);
}

/*
 * DS records are not allowed to exist without corresponding NS records,
 * draft-ietf-dnsext-delegation-signer-11.txt, 2.2 Protocol Change,
 * "DS RRsets MUST NOT appear at non-delegation points or at a zone's apex".
 */

static isc_result_t
remove_orphaned_ds(dns_db_t *db, dns_dbversion_t *newver, dns_diff_t *diff) {
	isc_result_t result;
	isc_boolean_t ns_exists, ds_exists;
	dns_difftuple_t *t;

	for (t = ISC_LIST_HEAD(diff->tuples);
	     t != NULL;
	     t = ISC_LIST_NEXT(t, link)) {
		if (t->op != DNS_DIFFOP_DEL ||
		    t->rdata.type != dns_rdatatype_ns)
			continue;
		CHECK(rrset_exists(db, newver, &t->name, dns_rdatatype_ns, 0,
				   &ns_exists));
		if (ns_exists)
			continue;
		CHECK(rrset_exists(db, newver, &t->name, dns_rdatatype_ds, 0,
				   &ds_exists));
		if (!ds_exists)
			continue;
		CHECK(delete_if(true_p, db, newver, &t->name,
				dns_rdatatype_ds, 0, NULL, diff));
	}
	return (ISC_R_SUCCESS);

 failure:
	return (result);
}

static void
update_action(isc_task_t *task, isc_event_t *event) {
	update_event_t *uev = (update_event_t *) event;
	dns_zone_t *zone = uev->zone;
	ns_client_t *client = (ns_client_t *)event->ev_arg;

	isc_result_t result;
	dns_db_t *db = NULL;
	dns_dbversion_t *oldver = NULL;
	dns_dbversion_t *ver = NULL;
	dns_diff_t diff; 	/* Pending updates. */
	dns_diff_t temp; 	/* Pending RR existence assertions. */
	isc_boolean_t soa_serial_changed = ISC_FALSE;
	isc_mem_t *mctx = client->mctx;
	dns_rdatatype_t covers;
	dns_message_t *request = client->message;
	dns_rdataclass_t zoneclass;
	dns_name_t *zonename;
	dns_ssutable_t *ssutable = NULL;
	dns_fixedname_t tmpnamefixed;
	dns_name_t *tmpname = NULL;

	INSIST(event->ev_type == DNS_EVENT_UPDATE);

	dns_diff_init(mctx, &diff);
	dns_diff_init(mctx, &temp);

	CHECK(dns_zone_getdb(zone, &db));
	zonename = dns_db_origin(db);
	zoneclass = dns_db_class(db);
	dns_zone_getssutable(zone, &ssutable);
	dns_db_currentversion(db, &oldver);
	CHECK(dns_db_newversion(db, &ver));

	/*
	 * Check prerequisites.
	 */

	for (result = dns_message_firstname(request, DNS_SECTION_PREREQUISITE);
	     result == ISC_R_SUCCESS;
	     result = dns_message_nextname(request, DNS_SECTION_PREREQUISITE))
	{
		dns_name_t *name = NULL;
		dns_rdata_t rdata = DNS_RDATA_INIT;
		dns_ttl_t ttl;
		dns_rdataclass_t update_class;
		isc_boolean_t flag;

		get_current_rr(request, DNS_SECTION_PREREQUISITE, zoneclass,
			       &name, &rdata, &covers, &ttl, &update_class);

		if (ttl != 0)
			FAILC(DNS_R_FORMERR, "prerequisite TTL is not zero");

		if (! dns_name_issubdomain(name, zonename))
			FAILN(DNS_R_NOTZONE, name,
				"prerequisite name is out of zone");

		if (update_class == dns_rdataclass_any) {
			if (rdata.length != 0)
				FAILC(DNS_R_FORMERR,
				      "class ANY prerequisite "
				      "RDATA is not empty");
			if (rdata.type == dns_rdatatype_any) {
				CHECK(name_exists(db, ver, name, &flag));
				if (! flag) {
					FAILN(DNS_R_NXDOMAIN, name,
					      "'name in use' prerequisite "
					      "not satisfied");
				}
			} else {
				CHECK(rrset_exists(db, ver, name,
						   rdata.type, covers, &flag));
				if (! flag) {
					/* RRset does not exist. */
					FAILNT(DNS_R_NXRRSET, name, rdata.type,
					"'rrset exists (value independent)' "
					"prerequisite not satisfied");
				}
			}
		} else if (update_class == dns_rdataclass_none) {
			if (rdata.length != 0)
				FAILC(DNS_R_FORMERR,
				      "class NONE prerequisite "
				      "RDATA is not empty");
			if (rdata.type == dns_rdatatype_any) {
				CHECK(name_exists(db, ver, name, &flag));
				if (flag) {
					FAILN(DNS_R_YXDOMAIN, name,
					      "'name not in use' prerequisite "
					      "not satisfied");
				}
			} else {
				CHECK(rrset_exists(db, ver, name,
						   rdata.type, covers, &flag));
				if (flag) {
					/* RRset exists. */
					FAILNT(DNS_R_YXRRSET, name, rdata.type,
					       "'rrset does not exist' "
					       "prerequisite not satisfied");
				}
			}
		} else if (update_class == zoneclass) {
			/* "temp<rr.name, rr.type> += rr;" */
			result = temp_append(&temp, name, &rdata);
			if (result != ISC_R_SUCCESS) {
				UNEXPECTED_ERROR(__FILE__, __LINE__,
					 "temp entry creation failed: %s",
						 dns_result_totext(result));
				FAIL(ISC_R_UNEXPECTED);
			}
		} else {
			FAILC(DNS_R_FORMERR, "malformed prerequisite");
		}
	}
	if (result != ISC_R_NOMORE)
		FAIL(result);


	/*
	 * Perform the final check of the "rrset exists (value dependent)"
	 * prerequisites.
	 */
	if (ISC_LIST_HEAD(temp.tuples) != NULL) {
		dns_rdatatype_t type;

		/*
		 * Sort the prerequisite records by owner name,
		 * type, and rdata.
		 */
		result = dns_diff_sort(&temp, temp_order);
		if (result != ISC_R_SUCCESS)
			FAILC(result, "'RRset exists (value dependent)' "
			      "prerequisite not satisfied");

		dns_fixedname_init(&tmpnamefixed);
		tmpname = dns_fixedname_name(&tmpnamefixed);
		result = temp_check(mctx, &temp, db, ver, tmpname, &type);
		if (result != ISC_R_SUCCESS)
			FAILNT(result, tmpname, type,
			       "'RRset exists (value dependent)' "
			       "prerequisite not satisfied");
	}

	update_log(client, zone, LOGLEVEL_DEBUG,
		   "prerequisites are OK");

	/*
	 * Check Requestor's Permissions.  It seems a bit silly to do this
	 * only after prerequisite testing, but that is what RFC2136 says.
	 */
	result = ISC_R_SUCCESS;
	if (ssutable == NULL)
		CHECK(checkupdateacl(client, dns_zone_getupdateacl(zone),
				     "update", zonename, ISC_FALSE));
	else if (client->signer == NULL)
		CHECK(checkupdateacl(client, NULL, "update", zonename,
				     ISC_FALSE));
	
	if (dns_zone_getupdatedisabled(zone))
		FAILC(DNS_R_REFUSED, "dynamic update temporarily disabled");

	/*
	 * Perform the Update Section Prescan.
	 */

	for (result = dns_message_firstname(request, DNS_SECTION_UPDATE);
	     result == ISC_R_SUCCESS;
	     result = dns_message_nextname(request, DNS_SECTION_UPDATE))
	{
		dns_name_t *name = NULL;
		dns_rdata_t rdata = DNS_RDATA_INIT;
		dns_ttl_t ttl;
		dns_rdataclass_t update_class;
		get_current_rr(request, DNS_SECTION_UPDATE, zoneclass,
			       &name, &rdata, &covers, &ttl, &update_class);

		if (! dns_name_issubdomain(name, zonename))
			FAILC(DNS_R_NOTZONE,
			      "update RR is outside zone");
		if (update_class == zoneclass) {
			/*
			 * Check for meta-RRs.  The RFC2136 pseudocode says
			 * check for ANY|AXFR|MAILA|MAILB, but the text adds
			 * "or any other QUERY metatype"
			 */
			if (dns_rdatatype_ismeta(rdata.type)) {
				FAILC(DNS_R_FORMERR,
				      "meta-RR in update");
			}
			result = dns_zone_checknames(zone, name, &rdata);
			if (result != ISC_R_SUCCESS)
				FAIL(DNS_R_REFUSED);
		} else if (update_class == dns_rdataclass_any) {
			if (ttl != 0 || rdata.length != 0 ||
			    (dns_rdatatype_ismeta(rdata.type) &&
			     rdata.type != dns_rdatatype_any))
				FAILC(DNS_R_FORMERR,
				      "meta-RR in update");
		} else if (update_class == dns_rdataclass_none) {
			if (ttl != 0 ||
			    dns_rdatatype_ismeta(rdata.type))
				FAILC(DNS_R_FORMERR,
				      "meta-RR in update");
		} else {
			update_log(client, zone, ISC_LOG_WARNING,
				   "update RR has incorrect class %d",
				   update_class);
			FAIL(DNS_R_FORMERR);
		}
		/*
		 * draft-ietf-dnsind-simple-secure-update-01 says
		 * "Unlike traditional dynamic update, the client
		 * is forbidden from updating NSEC records."
		 */
		if (dns_db_issecure(db)) {
			if (rdata.type == dns_rdatatype_nsec) {
				FAILC(DNS_R_REFUSED,
				      "explicit NSEC updates are not allowed "
				      "in secure zones");
			}
			else if (rdata.type == dns_rdatatype_rrsig) {
				FAILC(DNS_R_REFUSED,
				      "explicit RRSIG updates are currently not "
				      "supported in secure zones");
			}
		}

		if (ssutable != NULL && client->signer != NULL) {
			if (rdata.type != dns_rdatatype_any) {
				if (!dns_ssutable_checkrules(ssutable,
							     client->signer,
							     name, rdata.type))
					FAILC(DNS_R_REFUSED,
					      "rejected by secure update");
			}
			else {
				if (!ssu_checkall(db, ver, name, ssutable,
						  client->signer))
					FAILC(DNS_R_REFUSED,
					      "rejected by secure update");
			}
		}
	}
	if (result != ISC_R_NOMORE)
		FAIL(result);

	update_log(client, zone, LOGLEVEL_DEBUG,
		   "update section prescan OK");

	/*
	 * Process the Update Section.
	 */

	for (result = dns_message_firstname(request, DNS_SECTION_UPDATE);
	     result == ISC_R_SUCCESS;
	     result = dns_message_nextname(request, DNS_SECTION_UPDATE))
	{
		dns_name_t *name = NULL;
		dns_rdata_t rdata = DNS_RDATA_INIT;
		dns_ttl_t ttl;
		dns_rdataclass_t update_class;
		isc_boolean_t flag;

		get_current_rr(request, DNS_SECTION_UPDATE, zoneclass,
			       &name, &rdata, &covers, &ttl, &update_class);

		if (update_class == zoneclass) {

			/*
			 * RFC 1123 doesn't allow MF and MD in master zones.				 */
			if (rdata.type == dns_rdatatype_md ||
			    rdata.type == dns_rdatatype_mf) {
				char typebuf[DNS_RDATATYPE_FORMATSIZE];

				dns_rdatatype_format(rdata.type, t