server.c

bind 9.3结合mysql数据库

	ns_interfacemgr_adjust(server->interfacemgr, list, ISC_TRUE);
	
 clean:
	ns_listenlist_detach(&list);
	return;

 fail:
	/*
	 * Even when we failed the procedure, most of other interfaces
	 * should work correctly.  We therefore just warn it.
	 */
	isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL,
		      NS_LOGMODULE_SERVER, ISC_LOG_WARNING,
		      "could not adjust the listen-on list; "
		      "some interfaces may not work");
	goto clean;
}

/*
 * This event callback is invoked to do periodic network
 * interface scanning.
 */
static void
interface_timer_tick(isc_task_t *task, isc_event_t *event) {
	isc_result_t result;
	ns_server_t *server = (ns_server_t *) event->ev_arg;
	INSIST(task == server->task);
	UNUSED(task);
	isc_event_free(&event);
	/*
	 * XXX should scan interfaces unlocked and get exclusive access
	 * only to replace ACLs.
	 */
	result = isc_task_beginexclusive(server->task);
	RUNTIME_CHECK(result == ISC_R_SUCCESS);
	scan_interfaces(server, ISC_FALSE);
	isc_task_endexclusive(server->task);
}

static void
heartbeat_timer_tick(isc_task_t *task, isc_event_t *event) {
	ns_server_t *server = (ns_server_t *) event->ev_arg;
	dns_view_t *view;

	UNUSED(task);
	isc_event_free(&event);
	view = ISC_LIST_HEAD(server->viewlist);
	while (view != NULL) {
		dns_view_dialup(view);
		view = ISC_LIST_NEXT(view, link);
	}
}

/*
 * Replace the current value of '*field', a dynamically allocated
 * string or NULL, with a dynamically allocated copy of the
 * null-terminated string pointed to by 'value', or NULL.
 */
static isc_result_t
setstring(ns_server_t *server, char **field, const char *value) {
	char *copy;

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

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

	*field = copy;
	return (ISC_R_SUCCESS);
}	

/*
 * Replace the current value of '*field', a dynamically allocated
 * string or NULL, with another dynamically allocated string
 * or NULL if whether 'obj' is a string or void value, respectively.
 */
static isc_result_t
setoptstring(ns_server_t *server, char **field, cfg_obj_t *obj) {
	if (cfg_obj_isvoid(obj))
		return (setstring(server, field, NULL));
	else
		return (setstring(server, field, cfg_obj_asstring(obj)));
}

static void
set_limit(cfg_obj_t **maps, const char *configname, const char *description,
	  isc_resource_t resourceid, isc_resourcevalue_t defaultvalue)
{
	cfg_obj_t *obj = NULL;
	char *resource;
	isc_resourcevalue_t value;
	isc_result_t result;

	if (ns_config_get(maps, configname, &obj) != ISC_R_SUCCESS)
		return;

	if (cfg_obj_isstring(obj)) {
		resource = cfg_obj_asstring(obj);
		if (strcasecmp(resource, "unlimited") == 0)
			value = ISC_RESOURCE_UNLIMITED;
		else {
			INSIST(strcasecmp(resource, "default") == 0);
			value = defaultvalue;
		}
	} else
		value = cfg_obj_asuint64(obj);

	result = isc_resource_setlimit(resourceid, value);
	isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL, NS_LOGMODULE_SERVER,
		      result == ISC_R_SUCCESS ?
		      	ISC_LOG_DEBUG(3) : ISC_LOG_WARNING,
		      "set maximum %s to %" ISC_PRINT_QUADFORMAT "d: %s",
		      description, value, isc_result_totext(result));
}

#define SETLIMIT(cfgvar, resource, description) \
	set_limit(maps, cfgvar, description, isc_resource_ ## resource, \
		  ns_g_init ## resource)

static void
set_limits(cfg_obj_t **maps) {
	SETLIMIT("stacksize", stacksize, "stack size");
	SETLIMIT("datasize", datasize, "data size");
	SETLIMIT("coresize", coresize, "core size");
	SETLIMIT("files", openfiles, "open files");
}

static isc_result_t
portlist_fromconf(dns_portlist_t *portlist, unsigned int family,
		  cfg_obj_t *ports)
{
	cfg_listelt_t *element;
	isc_result_t result = ISC_R_SUCCESS;

	for (element = cfg_list_first(ports);
	     element != NULL;
	     element = cfg_list_next(element)) {
		cfg_obj_t *obj = cfg_listelt_value(element);
		in_port_t port = (in_port_t)cfg_obj_asuint32(obj);
		
		result = dns_portlist_add(portlist, family, port);
		if (result != ISC_R_SUCCESS)
			break;
	}
	return (result);
}

static isc_result_t
load_configuration(const char *filename, ns_server_t *server,
		   isc_boolean_t first_time)
{
	isc_result_t result;
	cfg_parser_t *parser = NULL;
	cfg_obj_t *config;
	cfg_obj_t *options;
	cfg_obj_t *views;
	cfg_obj_t *obj;
	cfg_obj_t *v4ports, *v6ports;
	cfg_obj_t *maps[3];
	cfg_obj_t *builtin_views;
	cfg_listelt_t *element;
	dns_view_t *view = NULL;
	dns_view_t *view_next;
	dns_viewlist_t viewlist;
	dns_viewlist_t tmpviewlist;
	ns_aclconfctx_t aclconfctx;
	isc_uint32_t interface_interval;
	isc_uint32_t heartbeat_interval;
	isc_uint32_t udpsize;
	in_port_t listen_port;
	int i;

	ns_aclconfctx_init(&aclconfctx);
	ISC_LIST_INIT(viewlist);

	/* Ensure exclusive access to configuration data. */
	result = isc_task_beginexclusive(server->task);
	RUNTIME_CHECK(result == ISC_R_SUCCESS);	

	/*
	 * Parse the global default pseudo-config file.
	 */
	if (first_time) {
		CHECK(ns_config_parsedefaults(ns_g_parser, &ns_g_config));
		RUNTIME_CHECK(cfg_map_get(ns_g_config, "options",
					  &ns_g_defaults) ==
			      ISC_R_SUCCESS);
	}

	/*
	 * Parse the configuration file using the new config code.
	 */
	result = ISC_R_FAILURE;
	config = NULL;

	/*
	 * Unless this is lwresd with the -C option, parse the config file.
	 */
	if (!(ns_g_lwresdonly && lwresd_g_useresolvconf)) {
		isc_log_write(ns_g_lctx,
			      NS_LOGCATEGORY_GENERAL, NS_LOGMODULE_SERVER,
			      ISC_LOG_INFO, "loading configuration from '%s'",
			      filename);
		CHECK(cfg_parser_create(ns_g_mctx, ns_g_lctx, &parser));
		cfg_parser_setcallback(parser, directory_callback, NULL);
		result = cfg_parse_file(parser, filename, &cfg_type_namedconf,
					&config);
	}

	/*
	 * If this is lwresd with the -C option, or lwresd with no -C or -c
	 * option where the above parsing failed, parse resolv.conf.
	 */
	if (ns_g_lwresdonly &&
	    (lwresd_g_useresolvconf ||
	     (!ns_g_conffileset && result == ISC_R_FILENOTFOUND)))
	{
		isc_log_write(ns_g_lctx,
			      NS_LOGCATEGORY_GENERAL, NS_LOGMODULE_SERVER,
			      ISC_LOG_INFO, "loading configuration from '%s'",
			      lwresd_g_resolvconffile);
		if (parser != NULL)
			cfg_parser_destroy(&parser);
		CHECK(cfg_parser_create(ns_g_mctx, ns_g_lctx, &parser));
		result = ns_lwresd_parseeresolvconf(ns_g_mctx, parser,
						    &config);
	}
	CHECK(result);

	/*
	 * Check the validity of the configuration.
	 */
	CHECK(bind9_check_namedconf(config, ns_g_lctx, ns_g_mctx));

	/*
	 * Fill in the maps array, used for resolving defaults.
	 */
	i = 0;
	options = NULL;
	result = cfg_map_get(config, "options", &options);
	if (result == ISC_R_SUCCESS)
		maps[i++] = options;
	maps[i++] = ns_g_defaults;
	maps[i++] = NULL;

	/*
	 * Set process limits, which (usually) needs to be done as root.
	 */
	set_limits(maps);

	/*
	 * Configure various server options.
	 */
	configure_server_quota(maps, "transfers-out", &server->xfroutquota);
	configure_server_quota(maps, "tcp-clients", &server->tcpquota);
	configure_server_quota(maps, "recursive-clients",
			       &server->recursionquota);

	CHECK(configure_view_acl(NULL, config, "blackhole", &aclconfctx,
				 ns_g_mctx, &server->blackholeacl));
	if (server->blackholeacl != NULL)
		dns_dispatchmgr_setblackhole(ns_g_dispatchmgr,
					     server->blackholeacl);

	obj = NULL;
	result = ns_config_get(maps, "match-mapped-addresses", &obj);
	INSIST(result == ISC_R_SUCCESS);
	server->aclenv.match_mapped = cfg_obj_asboolean(obj);

	v4ports = NULL;
	v6ports = NULL;
	(void)ns_config_get(maps, "avoid-v4-udp-ports", &v4ports);
	(void)ns_config_get(maps, "avoid-v6-udp-ports", &v6ports);
	if (v4ports != NULL || v6ports != NULL) {
		dns_portlist_t *portlist = NULL;
		result = dns_portlist_create(ns_g_mctx, &portlist);
		if (result == ISC_R_SUCCESS && v4ports != NULL)
			result = portlist_fromconf(portlist, AF_INET, v4ports);
		if (result == ISC_R_SUCCESS && v6ports != NULL)
			portlist_fromconf(portlist, AF_INET6, v6ports);
		if (result == ISC_R_SUCCESS)
			dns_dispatchmgr_setblackportlist(ns_g_dispatchmgr, portlist);
		if (portlist != NULL)
			dns_portlist_detach(&portlist);
		CHECK(result);
	} else
		dns_dispatchmgr_setblackportlist(ns_g_dispatchmgr, NULL);

	/*
	 * Set the EDNS UDP size when we don't match a view.
	 */
	obj = NULL;
	result = ns_config_get(maps, "edns-udp-size", &obj);
	INSIST(result == ISC_R_SUCCESS);
	udpsize = cfg_obj_asuint32(obj);
	if (udpsize < 512)
		udpsize = 512;
	if (udpsize > 4096)
		udpsize = 4096;
	ns_g_udpsize = (isc_uint16_t)udpsize;

	/*
	 * Configure the zone manager.
	 */
	obj = NULL;
	result = ns_config_get(maps, "transfers-in", &obj);
	INSIST(result == ISC_R_SUCCESS);
	dns_zonemgr_settransfersin(server->zonemgr, cfg_obj_asuint32(obj));

	obj = NULL;
	result = ns_config_get(maps, "transfers-per-ns", &obj);
	INSIST(result == ISC_R_SUCCESS);
	dns_zonemgr_settransfersperns(server->zonemgr, cfg_obj_asuint32(obj));

	obj = NULL;
	result = ns_config_get(maps, "serial-query-rate", &obj);
	INSIST(result == ISC_R_SUCCESS);
	dns_zonemgr_setserialqueryrate(server->zonemgr, cfg_obj_asuint32(obj));

	/*
	 * Determine which port to use for listening for incoming connections.
	 */
	if (ns_g_port != 0)
		listen_port = ns_g_port;
	else
		CHECKM(ns_config_getport(config, &listen_port), "port");

	/*
	 * Find the listen queue depth.
	 */
	obj = NULL;
	result = ns_config_get(maps, "tcp-listen-queue", &obj);
	INSIST(result == ISC_R_SUCCESS);
	ns_g_listen = cfg_obj_asuint32(obj);
	if (ns_g_listen < 3)
		ns_g_listen = 3;

	/*
	 * Configure the interface manager according to the "listen-on"
	 * statement.
	 */
	{
		cfg_obj_t *clistenon = NULL;
		ns_listenlist_t *listenon = NULL;

		clistenon = NULL;
		/*
		 * Even though listen-on is present in the default
		 * configuration, we can't use it here, since it isn't
		 * used if we're in lwresd mode.  This way is easier.
		 */
		if (options != NULL)
			(void)cfg_map_get(options, "listen-on", &clistenon);
		if (clistenon != NULL) {
			result = ns_listenlist_fromconfig(clistenon,
							  config,
							  &aclconfctx,
							  ns_g_mctx,
							  &listenon);
		} else if (!ns_g_lwresdonly) {
			/*
			 * Not specified, use default.
			 */
			CHECK(ns_listenlist_default(ns_g_mctx, listen_port,
						    ISC_TRUE, &listenon));
		}
		if (listenon != NULL) {
			ns_interfacemgr_setlistenon4(server->interfacemgr,
						     listenon);
			ns_listenlist_detach(&listenon);
		}
	}
	/*
	 * Ditto for IPv6.
	 */
	{
		cfg_obj_t *clistenon = NULL;
		ns_listenlist_t *listenon = NULL;

		if (options != NULL)
			(void)cfg_map_get(options, "listen-on-v6", &clistenon);
		if (clistenon != NULL) {
			result = ns_listenlist_fromconfig(clistenon,
							  config,
							  &aclconfctx,
							  ns_g_mctx,
							  &listenon);
		} else if (!ns_g_lwresdonly) {
			/*
			 * Not specified, use default.
			 */
			CHECK(ns_listenlist_default(ns_g_mctx, listen_port,
						    ISC_FALSE, &listenon));
		}
		if (listenon != NULL) {
			ns_interfacemgr_setlistenon6(server->interfacemgr,
						     listenon);
			ns_listenlist_detach(&listenon);
		}
	}

	/*
	 * Rescan the interface list to pick up changes in the
	 * listen-on option.  It's important that we do this before we try
	 * to configure the query source, since the dispatcher we use might
	 * be shared with an interface.
	 */
	scan_interfaces(server, ISC_TRUE);

	/*
	 * Arrange for further interface scanning to occur periodically
	 * as specified by the "interface-interval" option.
	 */
	obj = NULL;
	result = ns_config_get(maps, "interface-interval", &obj);
	INSIST(result == ISC_R_SUCCESS);
	interface_interval = cfg_obj_asuint32(obj) * 60;
	if (interface_interval == 0) {
		CHECK(isc_timer_reset(server->interface_timer,
				      isc_timertype_inactive,
				      NULL, NULL, ISC_TRUE));
	} else if (server->interface_interval != interface_interval) {
		isc_interval_t interval;
		isc_interval_set(&interval, interface_interval, 0);
		CHECK(isc_timer_reset(server->interface_timer,
				      isc_timertype_ticker,
				      NULL, &interval, ISC_FALSE));
	}
	server->interface_interval = interface_interval;

	/*
	 * Configure the dialup heartbeat timer.
	 */
	obj = NULL;
	result = ns_config_get(maps, "heartbeat-interval", &obj);
	INSIST(result == ISC_R_SUCCESS);
	heartbeat_interval = cfg_obj_asuint32(obj) * 60;
	if (heartbeat_interval == 0) {
		CHECK(isc_timer_reset(server->heartbeat_timer,
				      isc_timertype_inactive,
				      NULL, NULL, ISC_TRUE));
	} else if (server->heartbeat_interval != heartbeat_interval) {
		isc_interval_t interval;
		isc_interval_set(&interval, heartbeat_interval, 0);
		CHECK(isc_timer_reset(server->heartbeat_timer,
				      isc_timertype_ticker,
				      NULL, &interval, ISC_FALSE));
	}
	server->heartbeat_interval = heartbeat_interval;

	/*
	 * Configure and freeze all explicit views.  Explicit
	 * views that have zones were already created at parsing
	 * time, but views with no zones must be created here.
	 */
	views = NULL;
	(void)cfg_map_get(config, "view", &views);
	for (element = cfg_list_first(views);
	     element != NULL;
	     element = cfg_list_next(element))
	{
		cfg_obj_t *vconfig = cfg_listelt_value(element);
		view = NULL;

		CHECK(create_view(vconfig, &viewlist, &view));
		INSIST(view != NULL);
		CHECK(configure_view(view, config, vconfig,
				     ns_g_mctx, &aclconfctx, ISC_TRUE));
		dns_view_freeze(view);
		dns_view_detach(&view);
	}

	/*
	 * Make sure we have a default view if and only if there
	 * were no explicit views.
	 */
	if (views == NULL) {
		/*
		 * No explicit views; there ought to be a default vi