[deliverable/linux.git] / net / netfilter / xt_connlimit.c

/*
 * netfilter module to limit the number of parallel tcp
 * connections per IP address.
 *   (c) 2000 Gerd Knorr <kraxel@bytesex.org>
 *   Nov 2002: Martin Bene <martin.bene@icomedias.com>:
 *		only ignore TIME_WAIT or gone connections
 *   (C) CC Computer Consultants GmbH, 2007
 *
 * based on ...
 *
 * Kernel module to match connection tracking information.
 * GPL (C) 1999  Rusty Russell (rusty@rustcorp.com.au).
 */
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/in.h>
#include <linux/in6.h>
#include <linux/ip.h>
#include <linux/ipv6.h>
#include <linux/jhash.h>
#include <linux/slab.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/random.h>
#include <linux/skbuff.h>
#include <linux/spinlock.h>
#include <linux/netfilter/nf_conntrack_tcp.h>
#include <linux/netfilter/x_tables.h>
#include <linux/netfilter/xt_connlimit.h>
#include <net/netfilter/nf_conntrack.h>
#include <net/netfilter/nf_conntrack_core.h>
#include <net/netfilter/nf_conntrack_tuple.h>
#include <net/netfilter/nf_conntrack_zones.h>

/* we will save the tuples of all connections we care about */
struct xt_connlimit_conn {
	struct list_head		list;
	struct nf_conntrack_tuple	tuple;
	union nf_inet_addr		addr;
};

struct xt_connlimit_data {
	struct list_head iphash[256];
	spinlock_t lock;
};

static u_int32_t connlimit_rnd __read_mostly;
static bool connlimit_rnd_inited __read_mostly;

static inline unsigned int connlimit_iphash(__be32 addr)
{
	return jhash_1word((__force __u32)addr, connlimit_rnd) & 0xFF;
}

static inline unsigned int
connlimit_iphash6(const union nf_inet_addr *addr,
                  const union nf_inet_addr *mask)
{
	union nf_inet_addr res;
	unsigned int i;

	for (i = 0; i < ARRAY_SIZE(addr->ip6); ++i)
		res.ip6[i] = addr->ip6[i] & mask->ip6[i];

	return jhash2((u32 *)res.ip6, ARRAY_SIZE(res.ip6), connlimit_rnd) & 0xFF;
}

static inline bool already_closed(const struct nf_conn *conn)
{
	if (nf_ct_protonum(conn) == IPPROTO_TCP)
		return conn->proto.tcp.state == TCP_CONNTRACK_TIME_WAIT ||
		       conn->proto.tcp.state == TCP_CONNTRACK_CLOSE;
	else
		return 0;
}

static inline unsigned int
same_source_net(const union nf_inet_addr *addr,
		const union nf_inet_addr *mask,
		const union nf_inet_addr *u3, u_int8_t family)
{
	if (family == NFPROTO_IPV4) {
		return (addr->ip & mask->ip) == (u3->ip & mask->ip);
	} else {
		union nf_inet_addr lh, rh;
		unsigned int i;

		for (i = 0; i < ARRAY_SIZE(addr->ip6); ++i) {
			lh.ip6[i] = addr->ip6[i] & mask->ip6[i];
			rh.ip6[i] = u3->ip6[i] & mask->ip6[i];
		}

		return memcmp(&lh.ip6, &rh.ip6, sizeof(lh.ip6)) == 0;
	}
}

static int count_them(struct net *net,
		      struct xt_connlimit_data *data,
		      const struct nf_conntrack_tuple *tuple,
		      const union nf_inet_addr *addr,
		      const union nf_inet_addr *mask,
		      u_int8_t family)
{
	const struct nf_conntrack_tuple_hash *found;
	struct xt_connlimit_conn *conn;
	struct xt_connlimit_conn *tmp;
	struct nf_conn *found_ct;
	struct list_head *hash;
	bool addit = true;
	int matches = 0;

	if (family == NFPROTO_IPV6)
		hash = &data->iphash[connlimit_iphash6(addr, mask)];
	else
		hash = &data->iphash[connlimit_iphash(addr->ip & mask->ip)];

	rcu_read_lock();

	/* check the saved connections */
	list_for_each_entry_safe(conn, tmp, hash, list) {
		found    = nf_conntrack_find_get(net, NF_CT_DEFAULT_ZONE,
						 &conn->tuple);
		found_ct = NULL;

		if (found != NULL)
			found_ct = nf_ct_tuplehash_to_ctrack(found);

		if (found_ct != NULL &&
		    nf_ct_tuple_equal(&conn->tuple, tuple) &&
		    !already_closed(found_ct))
			/*
			 * Just to be sure we have it only once in the list.
			 * We should not see tuples twice unless someone hooks
			 * this into a table without "-p tcp --syn".
			 */
			addit = false;

		if (found == NULL) {
			/* this one is gone */
			list_del(&conn->list);
			kfree(conn);
			continue;
		}

		if (already_closed(found_ct)) {
			/*
			 * we do not care about connections which are
			 * closed already -> ditch it
			 */
			nf_ct_put(found_ct);
			list_del(&conn->list);
			kfree(conn);
			continue;
		}

		if (same_source_net(addr, mask, &conn->addr, family))
			/* same source network -> be counted! */
			++matches;
		nf_ct_put(found_ct);
	}

	rcu_read_unlock();

	if (addit) {
		/* save the new connection in our list */
		conn = kzalloc(sizeof(*conn), GFP_ATOMIC);
		if (conn == NULL)
			return -ENOMEM;
		conn->tuple = *tuple;
		conn->addr = *addr;
		list_add(&conn->list, hash);
		++matches;
	}

	return matches;
}

static bool
connlimit_mt(const struct sk_buff *skb, struct xt_action_param *par)
{
	struct net *net = dev_net(par->in ? par->in : par->out);
	const struct xt_connlimit_info *info = par->matchinfo;
	union nf_inet_addr addr;
	struct nf_conntrack_tuple tuple;
	const struct nf_conntrack_tuple *tuple_ptr = &tuple;
	enum ip_conntrack_info ctinfo;
	const struct nf_conn *ct;
	int connections;

	ct = nf_ct_get(skb, &ctinfo);
	if (ct != NULL)
		tuple_ptr = &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple;
	else if (!nf_ct_get_tuplepr(skb, skb_network_offset(skb),
				    par->family, &tuple))
		goto hotdrop;

	if (par->family == NFPROTO_IPV6) {
		const struct ipv6hdr *iph = ipv6_hdr(skb);
		memcpy(&addr.ip6, (info->flags & XT_CONNLIMIT_DADDR) ?
		       &iph->daddr : &iph->saddr, sizeof(addr.ip6));
	} else {
		const struct iphdr *iph = ip_hdr(skb);
		addr.ip = (info->flags & XT_CONNLIMIT_DADDR) ?
			  iph->daddr : iph->saddr;
	}

	spin_lock_bh(&info->data->lock);
	connections = count_them(net, info->data, tuple_ptr, &addr,
	                         &info->mask, par->family);
	spin_unlock_bh(&info->data->lock);

	if (connections < 0)
		/* kmalloc failed, drop it entirely */
		goto hotdrop;

	return (connections > info->limit) ^
	       !!(info->flags & XT_CONNLIMIT_INVERT);

 hotdrop:
	par->hotdrop = true;
	return false;
}

static int connlimit_mt_check(const struct xt_mtchk_param *par)
{
	struct xt_connlimit_info *info = par->matchinfo;
	unsigned int i;
	int ret;

	if (unlikely(!connlimit_rnd_inited)) {
		get_random_bytes(&connlimit_rnd, sizeof(connlimit_rnd));
		connlimit_rnd_inited = true;
	}
	ret = nf_ct_l3proto_try_module_get(par->family);
	if (ret < 0) {
		pr_info("cannot load conntrack support for "
			"address family %u\n", par->family);
		return ret;
	}

	/* init private data */
	info->data = kmalloc(sizeof(struct xt_connlimit_data), GFP_KERNEL);
	if (info->data == NULL) {
		nf_ct_l3proto_module_put(par->family);
		return -ENOMEM;
	}

	spin_lock_init(&info->data->lock);
	for (i = 0; i < ARRAY_SIZE(info->data->iphash); ++i)
		INIT_LIST_HEAD(&info->data->iphash[i]);

	return 0;
}

static void connlimit_mt_destroy(const struct xt_mtdtor_param *par)
{
	const struct xt_connlimit_info *info = par->matchinfo;
	struct xt_connlimit_conn *conn;
	struct xt_connlimit_conn *tmp;
	struct list_head *hash = info->data->iphash;
	unsigned int i;

	nf_ct_l3proto_module_put(par->family);

	for (i = 0; i < ARRAY_SIZE(info->data->iphash); ++i) {
		list_for_each_entry_safe(conn, tmp, &hash[i], list) {
			list_del(&conn->list);
			kfree(conn);
		}
	}

	kfree(info->data);
}

static struct xt_match connlimit_mt_reg[] __read_mostly = {
	{
		.name       = "connlimit",
		.revision   = 0,
		.family     = NFPROTO_UNSPEC,
		.checkentry = connlimit_mt_check,
		.match      = connlimit_mt,
		.matchsize  = sizeof(struct xt_connlimit_info),
		.destroy    = connlimit_mt_destroy,
		.me         = THIS_MODULE,
	},
	{
		.name       = "connlimit",
		.revision   = 1,
		.family     = NFPROTO_UNSPEC,
		.checkentry = connlimit_mt_check,
		.match      = connlimit_mt,
		.matchsize  = sizeof(struct xt_connlimit_info),
		.destroy    = connlimit_mt_destroy,
		.me         = THIS_MODULE,
	},
};

static int __init connlimit_mt_init(void)
{
	return xt_register_matches(connlimit_mt_reg,
	       ARRAY_SIZE(connlimit_mt_reg));
}

static void __exit connlimit_mt_exit(void)
{
	xt_unregister_matches(connlimit_mt_reg, ARRAY_SIZE(connlimit_mt_reg));
}

module_init(connlimit_mt_init);
module_exit(connlimit_mt_exit);
MODULE_AUTHOR("Jan Engelhardt <jengelh@medozas.de>");
MODULE_DESCRIPTION("Xtables: Number of connections matching");
MODULE_LICENSE("GPL");
MODULE_ALIAS("ipt_connlimit");
MODULE_ALIAS("ip6t_connlimit");
Commit	Line	Data
370786f9 JE	1	/*
	2	* netfilter module to limit the number of parallel tcp
	3	* connections per IP address.
	4	* (c) 2000 Gerd Knorr <kraxel@bytesex.org>
	5	* Nov 2002: Martin Bene <martin.bene@icomedias.com>:
	6	* only ignore TIME_WAIT or gone connections
ba5dc275	7	* (C) CC Computer Consultants GmbH, 2007
370786f9 JE	8	*
	9	* based on ...
	10	*
	11	* Kernel module to match connection tracking information.
	12	* GPL (C) 1999 Rusty Russell (rusty@rustcorp.com.au).
	13	*/
8bee4bad	14	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
370786f9 JE	15	#include <linux/in.h>
	16	#include <linux/in6.h>
	17	#include <linux/ip.h>
	18	#include <linux/ipv6.h>
	19	#include <linux/jhash.h>
5a0e3ad6	20	#include <linux/slab.h>
370786f9 JE	21	#include <linux/list.h>
	22	#include <linux/module.h>
	23	#include <linux/random.h>
	24	#include <linux/skbuff.h>
	25	#include <linux/spinlock.h>
	26	#include <linux/netfilter/nf_conntrack_tcp.h>
	27	#include <linux/netfilter/x_tables.h>
	28	#include <linux/netfilter/xt_connlimit.h>
	29	#include <net/netfilter/nf_conntrack.h>
	30	#include <net/netfilter/nf_conntrack_core.h>
	31	#include <net/netfilter/nf_conntrack_tuple.h>
5d0aa2cc	32	#include <net/netfilter/nf_conntrack_zones.h>
370786f9 JE	33
	34	/* we will save the tuples of all connections we care about */
	35	struct xt_connlimit_conn {
8183e3a8 CG	36	struct list_head list;
	37	struct nf_conntrack_tuple tuple;
	38	union nf_inet_addr addr;
370786f9 JE	39	};
	40
	41	struct xt_connlimit_data {
	42	struct list_head iphash[256];
	43	spinlock_t lock;
	44	};
	45
294188ae JE	46	static u_int32_t connlimit_rnd __read_mostly;
294188ae JE	47	static bool connlimit_rnd_inited __read_mostly;
370786f9	48
a34c4589	49	static inline unsigned int connlimit_iphash(__be32 addr)
370786f9	50	{
a34c4589	51	return jhash_1word((__force __u32)addr, connlimit_rnd) & 0xFF;
370786f9 JE	52	}
	53
	54	static inline unsigned int
643a2c15 JE	55	connlimit_iphash6(const union nf_inet_addr *addr,
643a2c15 JE	56	const union nf_inet_addr *mask)
370786f9	57	{
643a2c15	58	union nf_inet_addr res;
370786f9 JE	59	unsigned int i;
370786f9 JE	60
370786f9 JE	61	for (i = 0; i < ARRAY_SIZE(addr->ip6); ++i)
	62	res.ip6[i] = addr->ip6[i] & mask->ip6[i];
	63
a34c4589	64	return jhash2((u32 *)res.ip6, ARRAY_SIZE(res.ip6), connlimit_rnd) & 0xFF;
370786f9 JE	65	}
	66
	67	static inline bool already_closed(const struct nf_conn *conn)
	68	{
5e8fbe2a	69	if (nf_ct_protonum(conn) == IPPROTO_TCP)
d2ee3f2c DW	70	return conn->proto.tcp.state == TCP_CONNTRACK_TIME_WAIT \|\|
d2ee3f2c DW	71	conn->proto.tcp.state == TCP_CONNTRACK_CLOSE;
370786f9 JE	72	else
	73	return 0;
	74	}
	75
	76	static inline unsigned int
643a2c15 JE	77	same_source_net(const union nf_inet_addr *addr,
643a2c15 JE	78	const union nf_inet_addr *mask,
76108cea	79	const union nf_inet_addr *u3, u_int8_t family)
370786f9	80	{
ee999d8b	81	if (family == NFPROTO_IPV4) {
370786f9 JE	82	return (addr->ip & mask->ip) == (u3->ip & mask->ip);
370786f9 JE	83	} else {
643a2c15	84	union nf_inet_addr lh, rh;
370786f9 JE	85	unsigned int i;
	86
	87	for (i = 0; i < ARRAY_SIZE(addr->ip6); ++i) {
	88	lh.ip6[i] = addr->ip6[i] & mask->ip6[i];
	89	rh.ip6[i] = u3->ip6[i] & mask->ip6[i];
	90	}
	91
	92	return memcmp(&lh.ip6, &rh.ip6, sizeof(lh.ip6)) == 0;
	93	}
	94	}
	95
83fc8102 AD	96	static int count_them(struct net *net,
83fc8102 AD	97	struct xt_connlimit_data *data,
370786f9	98	const struct nf_conntrack_tuple *tuple,
643a2c15 JE	99	const union nf_inet_addr *addr,
643a2c15 JE	100	const union nf_inet_addr *mask,
20b7975e	101	u_int8_t family)
370786f9	102	{
3cf93c96	103	const struct nf_conntrack_tuple_hash *found;
370786f9 JE	104	struct xt_connlimit_conn *conn;
370786f9 JE	105	struct xt_connlimit_conn *tmp;
ea781f19	106	struct nf_conn *found_ct;
370786f9 JE	107	struct list_head *hash;
	108	bool addit = true;
	109	int matches = 0;
	110
539054a8	111	if (family == NFPROTO_IPV6)
370786f9 JE	112	hash = &data->iphash[connlimit_iphash6(addr, mask)];
	113	else
	114	hash = &data->iphash[connlimit_iphash(addr->ip & mask->ip)];
	115
76507f69	116	rcu_read_lock();
370786f9 JE	117
	118	/* check the saved connections */
	119	list_for_each_entry_safe(conn, tmp, hash, list) {
5d0aa2cc PM	120	found = nf_conntrack_find_get(net, NF_CT_DEFAULT_ZONE,
5d0aa2cc PM	121	&conn->tuple);
370786f9 JE	122	found_ct = NULL;
	123
	124	if (found != NULL)
	125	found_ct = nf_ct_tuplehash_to_ctrack(found);
	126
	127	if (found_ct != NULL &&
	128	nf_ct_tuple_equal(&conn->tuple, tuple) &&
	129	!already_closed(found_ct))
	130	/*
	131	* Just to be sure we have it only once in the list.
	132	* We should not see tuples twice unless someone hooks
	133	* this into a table without "-p tcp --syn".
	134	*/
	135	addit = false;
	136
	137	if (found == NULL) {
	138	/* this one is gone */
	139	list_del(&conn->list);
	140	kfree(conn);
	141	continue;
	142	}
	143
	144	if (already_closed(found_ct)) {
	145	/*
	146	* we do not care about connections which are
	147	* closed already -> ditch it
	148	*/
ea781f19	149	nf_ct_put(found_ct);
370786f9 JE	150	list_del(&conn->list);
	151	kfree(conn);
	152	continue;
	153	}
	154
8183e3a8	155	if (same_source_net(addr, mask, &conn->addr, family))
370786f9 JE	156	/* same source network -> be counted! */
370786f9 JE	157	++matches;
ea781f19	158	nf_ct_put(found_ct);
370786f9 JE	159	}
370786f9 JE	160
76507f69	161	rcu_read_unlock();
370786f9 JE	162
	163	if (addit) {
	164	/* save the new connection in our list */
	165	conn = kzalloc(sizeof(*conn), GFP_ATOMIC);
	166	if (conn == NULL)
	167	return -ENOMEM;
	168	conn->tuple = *tuple;
8183e3a8	169	conn->addr = *addr;
370786f9 JE	170	list_add(&conn->list, hash);
	171	++matches;
	172	}
	173
	174	return matches;
	175	}
	176
d3c5ee6d	177	static bool
62fc8051	178	connlimit_mt(const struct sk_buff skb, struct xt_action_param par)
370786f9	179	{
83fc8102	180	struct net *net = dev_net(par->in ? par->in : par->out);
f7108a20	181	const struct xt_connlimit_info *info = par->matchinfo;
22c2d8bc	182	union nf_inet_addr addr;
370786f9 JE	183	struct nf_conntrack_tuple tuple;
	184	const struct nf_conntrack_tuple *tuple_ptr = &tuple;
	185	enum ip_conntrack_info ctinfo;
	186	const struct nf_conn *ct;
	187	int connections;
	188
	189	ct = nf_ct_get(skb, &ctinfo);
8183e3a8 CG	190	if (ct != NULL)
	191	tuple_ptr = &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple;
	192	else if (!nf_ct_get_tuplepr(skb, skb_network_offset(skb),
	193	par->family, &tuple))
370786f9 JE	194	goto hotdrop;
370786f9 JE	195
92f3b2b1	196	if (par->family == NFPROTO_IPV6) {
370786f9	197	const struct ipv6hdr *iph = ipv6_hdr(skb);
cc4fc022 JE	198	memcpy(&addr.ip6, (info->flags & XT_CONNLIMIT_DADDR) ?
cc4fc022 JE	199	&iph->daddr : &iph->saddr, sizeof(addr.ip6));
370786f9 JE	200	} else {
370786f9 JE	201	const struct iphdr *iph = ip_hdr(skb);
cc4fc022 JE	202	addr.ip = (info->flags & XT_CONNLIMIT_DADDR) ?
cc4fc022 JE	203	iph->daddr : iph->saddr;
370786f9 JE	204	}
	205
	206	spin_lock_bh(&info->data->lock);
83fc8102	207	connections = count_them(net, info->data, tuple_ptr, &addr,
20b7975e	208	&info->mask, par->family);
370786f9 JE	209	spin_unlock_bh(&info->data->lock);
370786f9 JE	210
1cc34c30	211	if (connections < 0)
370786f9	212	/* kmalloc failed, drop it entirely */
1cc34c30	213	goto hotdrop;
370786f9	214
cc4fc022 JE	215	return (connections > info->limit) ^
cc4fc022 JE	216	!!(info->flags & XT_CONNLIMIT_INVERT);
370786f9 JE	217
370786f9 JE	218	hotdrop:
b4ba2611	219	par->hotdrop = true;
370786f9 JE	220	return false;
	221	}
	222
b0f38452	223	static int connlimit_mt_check(const struct xt_mtchk_param *par)
370786f9	224	{
9b4fce7a	225	struct xt_connlimit_info *info = par->matchinfo;
370786f9	226	unsigned int i;
4a5a5c73	227	int ret;
370786f9	228
294188ae JE	229	if (unlikely(!connlimit_rnd_inited)) {
	230	get_random_bytes(&connlimit_rnd, sizeof(connlimit_rnd));
	231	connlimit_rnd_inited = true;
	232	}
4a5a5c73 JE	233	ret = nf_ct_l3proto_try_module_get(par->family);
4a5a5c73 JE	234	if (ret < 0) {
8bee4bad JE	235	pr_info("cannot load conntrack support for "
8bee4bad JE	236	"address family %u\n", par->family);
4a5a5c73	237	return ret;
370786f9 JE	238	}
	239
	240	/* init private data */
	241	info->data = kmalloc(sizeof(struct xt_connlimit_data), GFP_KERNEL);
	242	if (info->data == NULL) {
92f3b2b1	243	nf_ct_l3proto_module_put(par->family);
4a5a5c73	244	return -ENOMEM;
370786f9 JE	245	}
	246
	247	spin_lock_init(&info->data->lock);
	248	for (i = 0; i < ARRAY_SIZE(info->data->iphash); ++i)
	249	INIT_LIST_HEAD(&info->data->iphash[i]);
	250
bd414ee6	251	return 0;
370786f9 JE	252	}
370786f9 JE	253
6be3d859	254	static void connlimit_mt_destroy(const struct xt_mtdtor_param *par)
370786f9	255	{
6be3d859	256	const struct xt_connlimit_info *info = par->matchinfo;
370786f9 JE	257	struct xt_connlimit_conn *conn;
	258	struct xt_connlimit_conn *tmp;
	259	struct list_head *hash = info->data->iphash;
	260	unsigned int i;
	261
92f3b2b1	262	nf_ct_l3proto_module_put(par->family);
370786f9 JE	263
	264	for (i = 0; i < ARRAY_SIZE(info->data->iphash); ++i) {
	265	list_for_each_entry_safe(conn, tmp, &hash[i], list) {
	266	list_del(&conn->list);
	267	kfree(conn);
	268	}
	269	}
	270
	271	kfree(info->data);
	272	}
	273
cc4fc022 JE	274	static struct xt_match connlimit_mt_reg[] __read_mostly = {
	275	{
	276	.name = "connlimit",
	277	.revision = 0,
	278	.family = NFPROTO_UNSPEC,
	279	.checkentry = connlimit_mt_check,
	280	.match = connlimit_mt,
	281	.matchsize = sizeof(struct xt_connlimit_info),
	282	.destroy = connlimit_mt_destroy,
	283	.me = THIS_MODULE,
	284	},
	285	{
	286	.name = "connlimit",
	287	.revision = 1,
	288	.family = NFPROTO_UNSPEC,
	289	.checkentry = connlimit_mt_check,
	290	.match = connlimit_mt,
	291	.matchsize = sizeof(struct xt_connlimit_info),
	292	.destroy = connlimit_mt_destroy,
	293	.me = THIS_MODULE,
	294	},
370786f9 JE	295	};
370786f9 JE	296
d3c5ee6d	297	static int __init connlimit_mt_init(void)
370786f9	298	{
cc4fc022 JE	299	return xt_register_matches(connlimit_mt_reg,
cc4fc022 JE	300	ARRAY_SIZE(connlimit_mt_reg));
370786f9 JE	301	}
370786f9 JE	302
d3c5ee6d	303	static void __exit connlimit_mt_exit(void)
370786f9	304	{
cc4fc022	305	xt_unregister_matches(connlimit_mt_reg, ARRAY_SIZE(connlimit_mt_reg));
370786f9 JE	306	}
370786f9 JE	307
d3c5ee6d JE	308	module_init(connlimit_mt_init);
d3c5ee6d JE	309	module_exit(connlimit_mt_exit);
92f3b2b1	310	MODULE_AUTHOR("Jan Engelhardt <jengelh@medozas.de>");
2ae15b64	311	MODULE_DESCRIPTION("Xtables: Number of connections matching");
370786f9 JE	312	MODULE_LICENSE("GPL");
	313	MODULE_ALIAS("ipt_connlimit");
	314	MODULE_ALIAS("ip6t_connlimit");