ip_set_core.c revision 80d326fab534a5380e8f6e509a0b9076655a9670
1/* Copyright (C) 2000-2002 Joakim Axelsson <gozem@linux.nu>
2 *                         Patrick Schaaf <bof@bof.de>
3 * Copyright (C) 2003-2011 Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
8 */
9
10/* Kernel module for IP set management */
11
12#include <linux/init.h>
13#include <linux/module.h>
14#include <linux/moduleparam.h>
15#include <linux/ip.h>
16#include <linux/skbuff.h>
17#include <linux/spinlock.h>
18#include <linux/netlink.h>
19#include <linux/rculist.h>
20#include <net/netlink.h>
21
22#include <linux/netfilter.h>
23#include <linux/netfilter/x_tables.h>
24#include <linux/netfilter/nfnetlink.h>
25#include <linux/netfilter/ipset/ip_set.h>
26
27static LIST_HEAD(ip_set_type_list);		/* all registered set types */
28static DEFINE_MUTEX(ip_set_type_mutex);		/* protects ip_set_type_list */
29static DEFINE_RWLOCK(ip_set_ref_lock);		/* protects the set refs */
30
31static struct ip_set **ip_set_list;		/* all individual sets */
32static ip_set_id_t ip_set_max = CONFIG_IP_SET_MAX; /* max number of sets */
33
34#define STREQ(a, b)	(strncmp(a, b, IPSET_MAXNAMELEN) == 0)
35
36static unsigned int max_sets;
37
38module_param(max_sets, int, 0600);
39MODULE_PARM_DESC(max_sets, "maximal number of sets");
40MODULE_LICENSE("GPL");
41MODULE_AUTHOR("Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>");
42MODULE_DESCRIPTION("core IP set support");
43MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_IPSET);
44
45/*
46 * The set types are implemented in modules and registered set types
47 * can be found in ip_set_type_list. Adding/deleting types is
48 * serialized by ip_set_type_mutex.
49 */
50
51static inline void
52ip_set_type_lock(void)
53{
54	mutex_lock(&ip_set_type_mutex);
55}
56
57static inline void
58ip_set_type_unlock(void)
59{
60	mutex_unlock(&ip_set_type_mutex);
61}
62
63/* Register and deregister settype */
64
65static struct ip_set_type *
66find_set_type(const char *name, u8 family, u8 revision)
67{
68	struct ip_set_type *type;
69
70	list_for_each_entry_rcu(type, &ip_set_type_list, list)
71		if (STREQ(type->name, name) &&
72		    (type->family == family || type->family == AF_UNSPEC) &&
73		    revision >= type->revision_min &&
74		    revision <= type->revision_max)
75			return type;
76	return NULL;
77}
78
79/* Unlock, try to load a set type module and lock again */
80static bool
81load_settype(const char *name)
82{
83	nfnl_unlock();
84	pr_debug("try to load ip_set_%s\n", name);
85	if (request_module("ip_set_%s", name) < 0) {
86		pr_warning("Can't find ip_set type %s\n", name);
87		nfnl_lock();
88		return false;
89	}
90	nfnl_lock();
91	return true;
92}
93
94/* Find a set type and reference it */
95#define find_set_type_get(name, family, revision, found)	\
96	__find_set_type_get(name, family, revision, found, false)
97
98static int
99__find_set_type_get(const char *name, u8 family, u8 revision,
100		    struct ip_set_type **found, bool retry)
101{
102	struct ip_set_type *type;
103	int err;
104
105	if (retry && !load_settype(name))
106		return -IPSET_ERR_FIND_TYPE;
107
108	rcu_read_lock();
109	*found = find_set_type(name, family, revision);
110	if (*found) {
111		err = !try_module_get((*found)->me) ? -EFAULT : 0;
112		goto unlock;
113	}
114	/* Make sure the type is already loaded
115	 * but we don't support the revision */
116	list_for_each_entry_rcu(type, &ip_set_type_list, list)
117		if (STREQ(type->name, name)) {
118			err = -IPSET_ERR_FIND_TYPE;
119			goto unlock;
120		}
121	rcu_read_unlock();
122
123	return retry ? -IPSET_ERR_FIND_TYPE :
124		__find_set_type_get(name, family, revision, found, true);
125
126unlock:
127	rcu_read_unlock();
128	return err;
129}
130
131/* Find a given set type by name and family.
132 * If we succeeded, the supported minimal and maximum revisions are
133 * filled out.
134 */
135#define find_set_type_minmax(name, family, min, max) \
136	__find_set_type_minmax(name, family, min, max, false)
137
138static int
139__find_set_type_minmax(const char *name, u8 family, u8 *min, u8 *max,
140		       bool retry)
141{
142	struct ip_set_type *type;
143	bool found = false;
144
145	if (retry && !load_settype(name))
146		return -IPSET_ERR_FIND_TYPE;
147
148	*min = 255; *max = 0;
149	rcu_read_lock();
150	list_for_each_entry_rcu(type, &ip_set_type_list, list)
151		if (STREQ(type->name, name) &&
152		    (type->family == family || type->family == AF_UNSPEC)) {
153			found = true;
154			if (type->revision_min < *min)
155				*min = type->revision_min;
156			if (type->revision_max > *max)
157				*max = type->revision_max;
158		}
159	rcu_read_unlock();
160	if (found)
161		return 0;
162
163	return retry ? -IPSET_ERR_FIND_TYPE :
164		__find_set_type_minmax(name, family, min, max, true);
165}
166
167#define family_name(f)	((f) == AF_INET ? "inet" : \
168			 (f) == AF_INET6 ? "inet6" : "any")
169
170/* Register a set type structure. The type is identified by
171 * the unique triple of name, family and revision.
172 */
173int
174ip_set_type_register(struct ip_set_type *type)
175{
176	int ret = 0;
177
178	if (type->protocol != IPSET_PROTOCOL) {
179		pr_warning("ip_set type %s, family %s, revision %u:%u uses "
180			   "wrong protocol version %u (want %u)\n",
181			   type->name, family_name(type->family),
182			   type->revision_min, type->revision_max,
183			   type->protocol, IPSET_PROTOCOL);
184		return -EINVAL;
185	}
186
187	ip_set_type_lock();
188	if (find_set_type(type->name, type->family, type->revision_min)) {
189		/* Duplicate! */
190		pr_warning("ip_set type %s, family %s with revision min %u "
191			   "already registered!\n", type->name,
192			   family_name(type->family), type->revision_min);
193		ret = -EINVAL;
194		goto unlock;
195	}
196	list_add_rcu(&type->list, &ip_set_type_list);
197	pr_debug("type %s, family %s, revision %u:%u registered.\n",
198		 type->name, family_name(type->family),
199		 type->revision_min, type->revision_max);
200unlock:
201	ip_set_type_unlock();
202	return ret;
203}
204EXPORT_SYMBOL_GPL(ip_set_type_register);
205
206/* Unregister a set type. There's a small race with ip_set_create */
207void
208ip_set_type_unregister(struct ip_set_type *type)
209{
210	ip_set_type_lock();
211	if (!find_set_type(type->name, type->family, type->revision_min)) {
212		pr_warning("ip_set type %s, family %s with revision min %u "
213			   "not registered\n", type->name,
214			   family_name(type->family), type->revision_min);
215		goto unlock;
216	}
217	list_del_rcu(&type->list);
218	pr_debug("type %s, family %s with revision min %u unregistered.\n",
219		 type->name, family_name(type->family), type->revision_min);
220unlock:
221	ip_set_type_unlock();
222
223	synchronize_rcu();
224}
225EXPORT_SYMBOL_GPL(ip_set_type_unregister);
226
227/* Utility functions */
228void *
229ip_set_alloc(size_t size)
230{
231	void *members = NULL;
232
233	if (size < KMALLOC_MAX_SIZE)
234		members = kzalloc(size, GFP_KERNEL | __GFP_NOWARN);
235
236	if (members) {
237		pr_debug("%p: allocated with kmalloc\n", members);
238		return members;
239	}
240
241	members = vzalloc(size);
242	if (!members)
243		return NULL;
244	pr_debug("%p: allocated with vmalloc\n", members);
245
246	return members;
247}
248EXPORT_SYMBOL_GPL(ip_set_alloc);
249
250void
251ip_set_free(void *members)
252{
253	pr_debug("%p: free with %s\n", members,
254		 is_vmalloc_addr(members) ? "vfree" : "kfree");
255	if (is_vmalloc_addr(members))
256		vfree(members);
257	else
258		kfree(members);
259}
260EXPORT_SYMBOL_GPL(ip_set_free);
261
262static inline bool
263flag_nested(const struct nlattr *nla)
264{
265	return nla->nla_type & NLA_F_NESTED;
266}
267
268static const struct nla_policy ipaddr_policy[IPSET_ATTR_IPADDR_MAX + 1] = {
269	[IPSET_ATTR_IPADDR_IPV4]	= { .type = NLA_U32 },
270	[IPSET_ATTR_IPADDR_IPV6]	= { .type = NLA_BINARY,
271					    .len = sizeof(struct in6_addr) },
272};
273
274int
275ip_set_get_ipaddr4(struct nlattr *nla,  __be32 *ipaddr)
276{
277	struct nlattr *tb[IPSET_ATTR_IPADDR_MAX+1];
278
279	if (unlikely(!flag_nested(nla)))
280		return -IPSET_ERR_PROTOCOL;
281	if (nla_parse_nested(tb, IPSET_ATTR_IPADDR_MAX, nla, ipaddr_policy))
282		return -IPSET_ERR_PROTOCOL;
283	if (unlikely(!ip_set_attr_netorder(tb, IPSET_ATTR_IPADDR_IPV4)))
284		return -IPSET_ERR_PROTOCOL;
285
286	*ipaddr = nla_get_be32(tb[IPSET_ATTR_IPADDR_IPV4]);
287	return 0;
288}
289EXPORT_SYMBOL_GPL(ip_set_get_ipaddr4);
290
291int
292ip_set_get_ipaddr6(struct nlattr *nla, union nf_inet_addr *ipaddr)
293{
294	struct nlattr *tb[IPSET_ATTR_IPADDR_MAX+1];
295
296	if (unlikely(!flag_nested(nla)))
297		return -IPSET_ERR_PROTOCOL;
298
299	if (nla_parse_nested(tb, IPSET_ATTR_IPADDR_MAX, nla, ipaddr_policy))
300		return -IPSET_ERR_PROTOCOL;
301	if (unlikely(!ip_set_attr_netorder(tb, IPSET_ATTR_IPADDR_IPV6)))
302		return -IPSET_ERR_PROTOCOL;
303
304	memcpy(ipaddr, nla_data(tb[IPSET_ATTR_IPADDR_IPV6]),
305		sizeof(struct in6_addr));
306	return 0;
307}
308EXPORT_SYMBOL_GPL(ip_set_get_ipaddr6);
309
310/*
311 * Creating/destroying/renaming/swapping affect the existence and
312 * the properties of a set. All of these can be executed from userspace
313 * only and serialized by the nfnl mutex indirectly from nfnetlink.
314 *
315 * Sets are identified by their index in ip_set_list and the index
316 * is used by the external references (set/SET netfilter modules).
317 *
318 * The set behind an index may change by swapping only, from userspace.
319 */
320
321static inline void
322__ip_set_get(ip_set_id_t index)
323{
324	write_lock_bh(&ip_set_ref_lock);
325	ip_set_list[index]->ref++;
326	write_unlock_bh(&ip_set_ref_lock);
327}
328
329static inline void
330__ip_set_put(ip_set_id_t index)
331{
332	write_lock_bh(&ip_set_ref_lock);
333	BUG_ON(ip_set_list[index]->ref == 0);
334	ip_set_list[index]->ref--;
335	write_unlock_bh(&ip_set_ref_lock);
336}
337
338/*
339 * Add, del and test set entries from kernel.
340 *
341 * The set behind the index must exist and must be referenced
342 * so it can't be destroyed (or changed) under our foot.
343 */
344
345int
346ip_set_test(ip_set_id_t index, const struct sk_buff *skb,
347	    const struct xt_action_param *par,
348	    const struct ip_set_adt_opt *opt)
349{
350	struct ip_set *set = ip_set_list[index];
351	int ret = 0;
352
353	BUG_ON(set == NULL);
354	pr_debug("set %s, index %u\n", set->name, index);
355
356	if (opt->dim < set->type->dimension ||
357	    !(opt->family == set->family || set->family == AF_UNSPEC))
358		return 0;
359
360	read_lock_bh(&set->lock);
361	ret = set->variant->kadt(set, skb, par, IPSET_TEST, opt);
362	read_unlock_bh(&set->lock);
363
364	if (ret == -EAGAIN) {
365		/* Type requests element to be completed */
366		pr_debug("element must be competed, ADD is triggered\n");
367		write_lock_bh(&set->lock);
368		set->variant->kadt(set, skb, par, IPSET_ADD, opt);
369		write_unlock_bh(&set->lock);
370		ret = 1;
371	}
372
373	/* Convert error codes to nomatch */
374	return (ret < 0 ? 0 : ret);
375}
376EXPORT_SYMBOL_GPL(ip_set_test);
377
378int
379ip_set_add(ip_set_id_t index, const struct sk_buff *skb,
380	   const struct xt_action_param *par,
381	   const struct ip_set_adt_opt *opt)
382{
383	struct ip_set *set = ip_set_list[index];
384	int ret;
385
386	BUG_ON(set == NULL);
387	pr_debug("set %s, index %u\n", set->name, index);
388
389	if (opt->dim < set->type->dimension ||
390	    !(opt->family == set->family || set->family == AF_UNSPEC))
391		return 0;
392
393	write_lock_bh(&set->lock);
394	ret = set->variant->kadt(set, skb, par, IPSET_ADD, opt);
395	write_unlock_bh(&set->lock);
396
397	return ret;
398}
399EXPORT_SYMBOL_GPL(ip_set_add);
400
401int
402ip_set_del(ip_set_id_t index, const struct sk_buff *skb,
403	   const struct xt_action_param *par,
404	   const struct ip_set_adt_opt *opt)
405{
406	struct ip_set *set = ip_set_list[index];
407	int ret = 0;
408
409	BUG_ON(set == NULL);
410	pr_debug("set %s, index %u\n", set->name, index);
411
412	if (opt->dim < set->type->dimension ||
413	    !(opt->family == set->family || set->family == AF_UNSPEC))
414		return 0;
415
416	write_lock_bh(&set->lock);
417	ret = set->variant->kadt(set, skb, par, IPSET_DEL, opt);
418	write_unlock_bh(&set->lock);
419
420	return ret;
421}
422EXPORT_SYMBOL_GPL(ip_set_del);
423
424/*
425 * Find set by name, reference it once. The reference makes sure the
426 * thing pointed to, does not go away under our feet.
427 *
428 */
429ip_set_id_t
430ip_set_get_byname(const char *name, struct ip_set **set)
431{
432	ip_set_id_t i, index = IPSET_INVALID_ID;
433	struct ip_set *s;
434
435	for (i = 0; i < ip_set_max; i++) {
436		s = ip_set_list[i];
437		if (s != NULL && STREQ(s->name, name)) {
438			__ip_set_get(i);
439			index = i;
440			*set = s;
441		}
442	}
443
444	return index;
445}
446EXPORT_SYMBOL_GPL(ip_set_get_byname);
447
448/*
449 * If the given set pointer points to a valid set, decrement
450 * reference count by 1. The caller shall not assume the index
451 * to be valid, after calling this function.
452 *
453 */
454void
455ip_set_put_byindex(ip_set_id_t index)
456{
457	if (ip_set_list[index] != NULL)
458		__ip_set_put(index);
459}
460EXPORT_SYMBOL_GPL(ip_set_put_byindex);
461
462/*
463 * Get the name of a set behind a set index.
464 * We assume the set is referenced, so it does exist and
465 * can't be destroyed. The set cannot be renamed due to
466 * the referencing either.
467 *
468 */
469const char *
470ip_set_name_byindex(ip_set_id_t index)
471{
472	const struct ip_set *set = ip_set_list[index];
473
474	BUG_ON(set == NULL);
475	BUG_ON(set->ref == 0);
476
477	/* Referenced, so it's safe */
478	return set->name;
479}
480EXPORT_SYMBOL_GPL(ip_set_name_byindex);
481
482/*
483 * Routines to call by external subsystems, which do not
484 * call nfnl_lock for us.
485 */
486
487/*
488 * Find set by name, reference it once. The reference makes sure the
489 * thing pointed to, does not go away under our feet.
490 *
491 * The nfnl mutex is used in the function.
492 */
493ip_set_id_t
494ip_set_nfnl_get(const char *name)
495{
496	struct ip_set *s;
497	ip_set_id_t index;
498
499	nfnl_lock();
500	index = ip_set_get_byname(name, &s);
501	nfnl_unlock();
502
503	return index;
504}
505EXPORT_SYMBOL_GPL(ip_set_nfnl_get);
506
507/*
508 * Find set by index, reference it once. The reference makes sure the
509 * thing pointed to, does not go away under our feet.
510 *
511 * The nfnl mutex is used in the function.
512 */
513ip_set_id_t
514ip_set_nfnl_get_byindex(ip_set_id_t index)
515{
516	if (index > ip_set_max)
517		return IPSET_INVALID_ID;
518
519	nfnl_lock();
520	if (ip_set_list[index])
521		__ip_set_get(index);
522	else
523		index = IPSET_INVALID_ID;
524	nfnl_unlock();
525
526	return index;
527}
528EXPORT_SYMBOL_GPL(ip_set_nfnl_get_byindex);
529
530/*
531 * If the given set pointer points to a valid set, decrement
532 * reference count by 1. The caller shall not assume the index
533 * to be valid, after calling this function.
534 *
535 * The nfnl mutex is used in the function.
536 */
537void
538ip_set_nfnl_put(ip_set_id_t index)
539{
540	nfnl_lock();
541	ip_set_put_byindex(index);
542	nfnl_unlock();
543}
544EXPORT_SYMBOL_GPL(ip_set_nfnl_put);
545
546/*
547 * Communication protocol with userspace over netlink.
548 *
549 * The commands are serialized by the nfnl mutex.
550 */
551
552static inline bool
553protocol_failed(const struct nlattr * const tb[])
554{
555	return !tb[IPSET_ATTR_PROTOCOL] ||
556	       nla_get_u8(tb[IPSET_ATTR_PROTOCOL]) != IPSET_PROTOCOL;
557}
558
559static inline u32
560flag_exist(const struct nlmsghdr *nlh)
561{
562	return nlh->nlmsg_flags & NLM_F_EXCL ? 0 : IPSET_FLAG_EXIST;
563}
564
565static struct nlmsghdr *
566start_msg(struct sk_buff *skb, u32 pid, u32 seq, unsigned int flags,
567	  enum ipset_cmd cmd)
568{
569	struct nlmsghdr *nlh;
570	struct nfgenmsg *nfmsg;
571
572	nlh = nlmsg_put(skb, pid, seq, cmd | (NFNL_SUBSYS_IPSET << 8),
573			sizeof(*nfmsg), flags);
574	if (nlh == NULL)
575		return NULL;
576
577	nfmsg = nlmsg_data(nlh);
578	nfmsg->nfgen_family = AF_INET;
579	nfmsg->version = NFNETLINK_V0;
580	nfmsg->res_id = 0;
581
582	return nlh;
583}
584
585/* Create a set */
586
587static const struct nla_policy ip_set_create_policy[IPSET_ATTR_CMD_MAX + 1] = {
588	[IPSET_ATTR_PROTOCOL]	= { .type = NLA_U8 },
589	[IPSET_ATTR_SETNAME]	= { .type = NLA_NUL_STRING,
590				    .len = IPSET_MAXNAMELEN - 1 },
591	[IPSET_ATTR_TYPENAME]	= { .type = NLA_NUL_STRING,
592				    .len = IPSET_MAXNAMELEN - 1},
593	[IPSET_ATTR_REVISION]	= { .type = NLA_U8 },
594	[IPSET_ATTR_FAMILY]	= { .type = NLA_U8 },
595	[IPSET_ATTR_DATA]	= { .type = NLA_NESTED },
596};
597
598static ip_set_id_t
599find_set_id(const char *name)
600{
601	ip_set_id_t i, index = IPSET_INVALID_ID;
602	const struct ip_set *set;
603
604	for (i = 0; index == IPSET_INVALID_ID && i < ip_set_max; i++) {
605		set = ip_set_list[i];
606		if (set != NULL && STREQ(set->name, name))
607			index = i;
608	}
609	return index;
610}
611
612static inline struct ip_set *
613find_set(const char *name)
614{
615	ip_set_id_t index = find_set_id(name);
616
617	return index == IPSET_INVALID_ID ? NULL : ip_set_list[index];
618}
619
620static int
621find_free_id(const char *name, ip_set_id_t *index, struct ip_set **set)
622{
623	ip_set_id_t i;
624
625	*index = IPSET_INVALID_ID;
626	for (i = 0;  i < ip_set_max; i++) {
627		if (ip_set_list[i] == NULL) {
628			if (*index == IPSET_INVALID_ID)
629				*index = i;
630		} else if (STREQ(name, ip_set_list[i]->name)) {
631			/* Name clash */
632			*set = ip_set_list[i];
633			return -EEXIST;
634		}
635	}
636	if (*index == IPSET_INVALID_ID)
637		/* No free slot remained */
638		return -IPSET_ERR_MAX_SETS;
639	return 0;
640}
641
642static int
643ip_set_create(struct sock *ctnl, struct sk_buff *skb,
644	      const struct nlmsghdr *nlh,
645	      const struct nlattr * const attr[])
646{
647	struct ip_set *set, *clash = NULL;
648	ip_set_id_t index = IPSET_INVALID_ID;
649	struct nlattr *tb[IPSET_ATTR_CREATE_MAX+1] = {};
650	const char *name, *typename;
651	u8 family, revision;
652	u32 flags = flag_exist(nlh);
653	int ret = 0;
654
655	if (unlikely(protocol_failed(attr) ||
656		     attr[IPSET_ATTR_SETNAME] == NULL ||
657		     attr[IPSET_ATTR_TYPENAME] == NULL ||
658		     attr[IPSET_ATTR_REVISION] == NULL ||
659		     attr[IPSET_ATTR_FAMILY] == NULL ||
660		     (attr[IPSET_ATTR_DATA] != NULL &&
661		      !flag_nested(attr[IPSET_ATTR_DATA]))))
662		return -IPSET_ERR_PROTOCOL;
663
664	name = nla_data(attr[IPSET_ATTR_SETNAME]);
665	typename = nla_data(attr[IPSET_ATTR_TYPENAME]);
666	family = nla_get_u8(attr[IPSET_ATTR_FAMILY]);
667	revision = nla_get_u8(attr[IPSET_ATTR_REVISION]);
668	pr_debug("setname: %s, typename: %s, family: %s, revision: %u\n",
669		 name, typename, family_name(family), revision);
670
671	/*
672	 * First, and without any locks, allocate and initialize
673	 * a normal base set structure.
674	 */
675	set = kzalloc(sizeof(struct ip_set), GFP_KERNEL);
676	if (!set)
677		return -ENOMEM;
678	rwlock_init(&set->lock);
679	strlcpy(set->name, name, IPSET_MAXNAMELEN);
680	set->family = family;
681	set->revision = revision;
682
683	/*
684	 * Next, check that we know the type, and take
685	 * a reference on the type, to make sure it stays available
686	 * while constructing our new set.
687	 *
688	 * After referencing the type, we try to create the type
689	 * specific part of the set without holding any locks.
690	 */
691	ret = find_set_type_get(typename, family, revision, &(set->type));
692	if (ret)
693		goto out;
694
695	/*
696	 * Without holding any locks, create private part.
697	 */
698	if (attr[IPSET_ATTR_DATA] &&
699	    nla_parse_nested(tb, IPSET_ATTR_CREATE_MAX, attr[IPSET_ATTR_DATA],
700			     set->type->create_policy)) {
701		ret = -IPSET_ERR_PROTOCOL;
702		goto put_out;
703	}
704
705	ret = set->type->create(set, tb, flags);
706	if (ret != 0)
707		goto put_out;
708
709	/* BTW, ret==0 here. */
710
711	/*
712	 * Here, we have a valid, constructed set and we are protected
713	 * by the nfnl mutex. Find the first free index in ip_set_list
714	 * and check clashing.
715	 */
716	if ((ret = find_free_id(set->name, &index, &clash)) != 0) {
717		/* If this is the same set and requested, ignore error */
718		if (ret == -EEXIST &&
719		    (flags & IPSET_FLAG_EXIST) &&
720		    STREQ(set->type->name, clash->type->name) &&
721		    set->type->family == clash->type->family &&
722		    set->type->revision_min == clash->type->revision_min &&
723		    set->type->revision_max == clash->type->revision_max &&
724		    set->variant->same_set(set, clash))
725			ret = 0;
726		goto cleanup;
727	}
728
729	/*
730	 * Finally! Add our shiny new set to the list, and be done.
731	 */
732	pr_debug("create: '%s' created with index %u!\n", set->name, index);
733	ip_set_list[index] = set;
734
735	return ret;
736
737cleanup:
738	set->variant->destroy(set);
739put_out:
740	module_put(set->type->me);
741out:
742	kfree(set);
743	return ret;
744}
745
746/* Destroy sets */
747
748static const struct nla_policy
749ip_set_setname_policy[IPSET_ATTR_CMD_MAX + 1] = {
750	[IPSET_ATTR_PROTOCOL]	= { .type = NLA_U8 },
751	[IPSET_ATTR_SETNAME]	= { .type = NLA_NUL_STRING,
752				    .len = IPSET_MAXNAMELEN - 1 },
753};
754
755static void
756ip_set_destroy_set(ip_set_id_t index)
757{
758	struct ip_set *set = ip_set_list[index];
759
760	pr_debug("set: %s\n",  set->name);
761	ip_set_list[index] = NULL;
762
763	/* Must call it without holding any lock */
764	set->variant->destroy(set);
765	module_put(set->type->me);
766	kfree(set);
767}
768
769static int
770ip_set_destroy(struct sock *ctnl, struct sk_buff *skb,
771	       const struct nlmsghdr *nlh,
772	       const struct nlattr * const attr[])
773{
774	ip_set_id_t i;
775	int ret = 0;
776
777	if (unlikely(protocol_failed(attr)))
778		return -IPSET_ERR_PROTOCOL;
779
780	/* Commands are serialized and references are
781	 * protected by the ip_set_ref_lock.
782	 * External systems (i.e. xt_set) must call
783	 * ip_set_put|get_nfnl_* functions, that way we
784	 * can safely check references here.
785	 *
786	 * list:set timer can only decrement the reference
787	 * counter, so if it's already zero, we can proceed
788	 * without holding the lock.
789	 */
790	read_lock_bh(&ip_set_ref_lock);
791	if (!attr[IPSET_ATTR_SETNAME]) {
792		for (i = 0; i < ip_set_max; i++) {
793			if (ip_set_list[i] != NULL && ip_set_list[i]->ref) {
794				ret = -IPSET_ERR_BUSY;
795				goto out;
796			}
797		}
798		read_unlock_bh(&ip_set_ref_lock);
799		for (i = 0; i < ip_set_max; i++) {
800			if (ip_set_list[i] != NULL)
801				ip_set_destroy_set(i);
802		}
803	} else {
804		i = find_set_id(nla_data(attr[IPSET_ATTR_SETNAME]));
805		if (i == IPSET_INVALID_ID) {
806			ret = -ENOENT;
807			goto out;
808		} else if (ip_set_list[i]->ref) {
809			ret = -IPSET_ERR_BUSY;
810			goto out;
811		}
812		read_unlock_bh(&ip_set_ref_lock);
813
814		ip_set_destroy_set(i);
815	}
816	return 0;
817out:
818	read_unlock_bh(&ip_set_ref_lock);
819	return ret;
820}
821
822/* Flush sets */
823
824static void
825ip_set_flush_set(struct ip_set *set)
826{
827	pr_debug("set: %s\n",  set->name);
828
829	write_lock_bh(&set->lock);
830	set->variant->flush(set);
831	write_unlock_bh(&set->lock);
832}
833
834static int
835ip_set_flush(struct sock *ctnl, struct sk_buff *skb,
836	     const struct nlmsghdr *nlh,
837	     const struct nlattr * const attr[])
838{
839	ip_set_id_t i;
840
841	if (unlikely(protocol_failed(attr)))
842		return -IPSET_ERR_PROTOCOL;
843
844	if (!attr[IPSET_ATTR_SETNAME]) {
845		for (i = 0; i < ip_set_max; i++)
846			if (ip_set_list[i] != NULL)
847				ip_set_flush_set(ip_set_list[i]);
848	} else {
849		i = find_set_id(nla_data(attr[IPSET_ATTR_SETNAME]));
850		if (i == IPSET_INVALID_ID)
851			return -ENOENT;
852
853		ip_set_flush_set(ip_set_list[i]);
854	}
855
856	return 0;
857}
858
859/* Rename a set */
860
861static const struct nla_policy
862ip_set_setname2_policy[IPSET_ATTR_CMD_MAX + 1] = {
863	[IPSET_ATTR_PROTOCOL]	= { .type = NLA_U8 },
864	[IPSET_ATTR_SETNAME]	= { .type = NLA_NUL_STRING,
865				    .len = IPSET_MAXNAMELEN - 1 },
866	[IPSET_ATTR_SETNAME2]	= { .type = NLA_NUL_STRING,
867				    .len = IPSET_MAXNAMELEN - 1 },
868};
869
870static int
871ip_set_rename(struct sock *ctnl, struct sk_buff *skb,
872	      const struct nlmsghdr *nlh,
873	      const struct nlattr * const attr[])
874{
875	struct ip_set *set;
876	const char *name2;
877	ip_set_id_t i;
878	int ret = 0;
879
880	if (unlikely(protocol_failed(attr) ||
881		     attr[IPSET_ATTR_SETNAME] == NULL ||
882		     attr[IPSET_ATTR_SETNAME2] == NULL))
883		return -IPSET_ERR_PROTOCOL;
884
885	set = find_set(nla_data(attr[IPSET_ATTR_SETNAME]));
886	if (set == NULL)
887		return -ENOENT;
888
889	read_lock_bh(&ip_set_ref_lock);
890	if (set->ref != 0) {
891		ret = -IPSET_ERR_REFERENCED;
892		goto out;
893	}
894
895	name2 = nla_data(attr[IPSET_ATTR_SETNAME2]);
896	for (i = 0; i < ip_set_max; i++) {
897		if (ip_set_list[i] != NULL &&
898		    STREQ(ip_set_list[i]->name, name2)) {
899			ret = -IPSET_ERR_EXIST_SETNAME2;
900			goto out;
901		}
902	}
903	strncpy(set->name, name2, IPSET_MAXNAMELEN);
904
905out:
906	read_unlock_bh(&ip_set_ref_lock);
907	return ret;
908}
909
910/* Swap two sets so that name/index points to the other.
911 * References and set names are also swapped.
912 *
913 * The commands are serialized by the nfnl mutex and references are
914 * protected by the ip_set_ref_lock. The kernel interfaces
915 * do not hold the mutex but the pointer settings are atomic
916 * so the ip_set_list always contains valid pointers to the sets.
917 */
918
919static int
920ip_set_swap(struct sock *ctnl, struct sk_buff *skb,
921	    const struct nlmsghdr *nlh,
922	    const struct nlattr * const attr[])
923{
924	struct ip_set *from, *to;
925	ip_set_id_t from_id, to_id;
926	char from_name[IPSET_MAXNAMELEN];
927
928	if (unlikely(protocol_failed(attr) ||
929		     attr[IPSET_ATTR_SETNAME] == NULL ||
930		     attr[IPSET_ATTR_SETNAME2] == NULL))
931		return -IPSET_ERR_PROTOCOL;
932
933	from_id = find_set_id(nla_data(attr[IPSET_ATTR_SETNAME]));
934	if (from_id == IPSET_INVALID_ID)
935		return -ENOENT;
936
937	to_id = find_set_id(nla_data(attr[IPSET_ATTR_SETNAME2]));
938	if (to_id == IPSET_INVALID_ID)
939		return -IPSET_ERR_EXIST_SETNAME2;
940
941	from = ip_set_list[from_id];
942	to = ip_set_list[to_id];
943
944	/* Features must not change.
945	 * Not an artificial restriction anymore, as we must prevent
946	 * possible loops created by swapping in setlist type of sets. */
947	if (!(from->type->features == to->type->features &&
948	      from->type->family == to->type->family))
949		return -IPSET_ERR_TYPE_MISMATCH;
950
951	strncpy(from_name, from->name, IPSET_MAXNAMELEN);
952	strncpy(from->name, to->name, IPSET_MAXNAMELEN);
953	strncpy(to->name, from_name, IPSET_MAXNAMELEN);
954
955	write_lock_bh(&ip_set_ref_lock);
956	swap(from->ref, to->ref);
957	ip_set_list[from_id] = to;
958	ip_set_list[to_id] = from;
959	write_unlock_bh(&ip_set_ref_lock);
960
961	return 0;
962}
963
964/* List/save set data */
965
966#define DUMP_INIT	0
967#define DUMP_ALL	1
968#define DUMP_ONE	2
969#define DUMP_LAST	3
970
971#define DUMP_TYPE(arg)		(((u32)(arg)) & 0x0000FFFF)
972#define DUMP_FLAGS(arg)		(((u32)(arg)) >> 16)
973
974static int
975ip_set_dump_done(struct netlink_callback *cb)
976{
977	if (cb->args[2]) {
978		pr_debug("release set %s\n", ip_set_list[cb->args[1]]->name);
979		ip_set_put_byindex((ip_set_id_t) cb->args[1]);
980	}
981	return 0;
982}
983
984static inline void
985dump_attrs(struct nlmsghdr *nlh)
986{
987	const struct nlattr *attr;
988	int rem;
989
990	pr_debug("dump nlmsg\n");
991	nlmsg_for_each_attr(attr, nlh, sizeof(struct nfgenmsg), rem) {
992		pr_debug("type: %u, len %u\n", nla_type(attr), attr->nla_len);
993	}
994}
995
996static int
997dump_init(struct netlink_callback *cb)
998{
999	struct nlmsghdr *nlh = nlmsg_hdr(cb->skb);
1000	int min_len = NLMSG_SPACE(sizeof(struct nfgenmsg));
1001	struct nlattr *cda[IPSET_ATTR_CMD_MAX+1];
1002	struct nlattr *attr = (void *)nlh + min_len;
1003	u32 dump_type;
1004	ip_set_id_t index;
1005
1006	/* Second pass, so parser can't fail */
1007	nla_parse(cda, IPSET_ATTR_CMD_MAX,
1008		  attr, nlh->nlmsg_len - min_len, ip_set_setname_policy);
1009
1010	/* cb->args[0] : dump single set/all sets
1011	 *         [1] : set index
1012	 *         [..]: type specific
1013	 */
1014
1015	if (cda[IPSET_ATTR_SETNAME]) {
1016		index = find_set_id(nla_data(cda[IPSET_ATTR_SETNAME]));
1017		if (index == IPSET_INVALID_ID)
1018			return -ENOENT;
1019
1020		dump_type = DUMP_ONE;
1021		cb->args[1] = index;
1022	} else
1023		dump_type = DUMP_ALL;
1024
1025	if (cda[IPSET_ATTR_FLAGS]) {
1026		u32 f = ip_set_get_h32(cda[IPSET_ATTR_FLAGS]);
1027		dump_type |= (f << 16);
1028	}
1029	cb->args[0] = dump_type;
1030
1031	return 0;
1032}
1033
1034static int
1035ip_set_dump_start(struct sk_buff *skb, struct netlink_callback *cb)
1036{
1037	ip_set_id_t index = IPSET_INVALID_ID, max;
1038	struct ip_set *set = NULL;
1039	struct nlmsghdr *nlh = NULL;
1040	unsigned int flags = NETLINK_CB(cb->skb).pid ? NLM_F_MULTI : 0;
1041	u32 dump_type, dump_flags;
1042	int ret = 0;
1043
1044	if (!cb->args[0]) {
1045		ret = dump_init(cb);
1046		if (ret < 0) {
1047			nlh = nlmsg_hdr(cb->skb);
1048			/* We have to create and send the error message
1049			 * manually :-( */
1050			if (nlh->nlmsg_flags & NLM_F_ACK)
1051				netlink_ack(cb->skb, nlh, ret);
1052			return ret;
1053		}
1054	}
1055
1056	if (cb->args[1] >= ip_set_max)
1057		goto out;
1058
1059	dump_type = DUMP_TYPE(cb->args[0]);
1060	dump_flags = DUMP_FLAGS(cb->args[0]);
1061	max = dump_type == DUMP_ONE ? cb->args[1] + 1 : ip_set_max;
1062dump_last:
1063	pr_debug("args[0]: %u %u args[1]: %ld\n",
1064		 dump_type, dump_flags, cb->args[1]);
1065	for (; cb->args[1] < max; cb->args[1]++) {
1066		index = (ip_set_id_t) cb->args[1];
1067		set = ip_set_list[index];
1068		if (set == NULL) {
1069			if (dump_type == DUMP_ONE) {
1070				ret = -ENOENT;
1071				goto out;
1072			}
1073			continue;
1074		}
1075		/* When dumping all sets, we must dump "sorted"
1076		 * so that lists (unions of sets) are dumped last.
1077		 */
1078		if (dump_type != DUMP_ONE &&
1079		    ((dump_type == DUMP_ALL) ==
1080		     !!(set->type->features & IPSET_DUMP_LAST)))
1081			continue;
1082		pr_debug("List set: %s\n", set->name);
1083		if (!cb->args[2]) {
1084			/* Start listing: make sure set won't be destroyed */
1085			pr_debug("reference set\n");
1086			__ip_set_get(index);
1087		}
1088		nlh = start_msg(skb, NETLINK_CB(cb->skb).pid,
1089				cb->nlh->nlmsg_seq, flags,
1090				IPSET_CMD_LIST);
1091		if (!nlh) {
1092			ret = -EMSGSIZE;
1093			goto release_refcount;
1094		}
1095		NLA_PUT_U8(skb, IPSET_ATTR_PROTOCOL, IPSET_PROTOCOL);
1096		NLA_PUT_STRING(skb, IPSET_ATTR_SETNAME, set->name);
1097		if (dump_flags & IPSET_FLAG_LIST_SETNAME)
1098			goto next_set;
1099		switch (cb->args[2]) {
1100		case 0:
1101			/* Core header data */
1102			NLA_PUT_STRING(skb, IPSET_ATTR_TYPENAME,
1103				       set->type->name);
1104			NLA_PUT_U8(skb, IPSET_ATTR_FAMILY,
1105				   set->family);
1106			NLA_PUT_U8(skb, IPSET_ATTR_REVISION,
1107				   set->revision);
1108			ret = set->variant->head(set, skb);
1109			if (ret < 0)
1110				goto release_refcount;
1111			if (dump_flags & IPSET_FLAG_LIST_HEADER)
1112				goto next_set;
1113			/* Fall through and add elements */
1114		default:
1115			read_lock_bh(&set->lock);
1116			ret = set->variant->list(set, skb, cb);
1117			read_unlock_bh(&set->lock);
1118			if (!cb->args[2])
1119				/* Set is done, proceed with next one */
1120				goto next_set;
1121			goto release_refcount;
1122		}
1123	}
1124	/* If we dump all sets, continue with dumping last ones */
1125	if (dump_type == DUMP_ALL) {
1126		dump_type = DUMP_LAST;
1127		cb->args[0] = dump_type | (dump_flags << 16);
1128		cb->args[1] = 0;
1129		goto dump_last;
1130	}
1131	goto out;
1132
1133nla_put_failure:
1134	ret = -EFAULT;
1135next_set:
1136	if (dump_type == DUMP_ONE)
1137		cb->args[1] = IPSET_INVALID_ID;
1138	else
1139		cb->args[1]++;
1140release_refcount:
1141	/* If there was an error or set is done, release set */
1142	if (ret || !cb->args[2]) {
1143		pr_debug("release set %s\n", ip_set_list[index]->name);
1144		ip_set_put_byindex(index);
1145		cb->args[2] = 0;
1146	}
1147out:
1148	if (nlh) {
1149		nlmsg_end(skb, nlh);
1150		pr_debug("nlmsg_len: %u\n", nlh->nlmsg_len);
1151		dump_attrs(nlh);
1152	}
1153
1154	return ret < 0 ? ret : skb->len;
1155}
1156
1157static int
1158ip_set_dump(struct sock *ctnl, struct sk_buff *skb,
1159	    const struct nlmsghdr *nlh,
1160	    const struct nlattr * const attr[])
1161{
1162	if (unlikely(protocol_failed(attr)))
1163		return -IPSET_ERR_PROTOCOL;
1164
1165	{
1166		struct netlink_dump_control c = {
1167			.dump = ip_set_dump_start,
1168			.done = ip_set_dump_done,
1169		};
1170		return netlink_dump_start(ctnl, skb, nlh, &c);
1171	}
1172}
1173
1174/* Add, del and test */
1175
1176static const struct nla_policy ip_set_adt_policy[IPSET_ATTR_CMD_MAX + 1] = {
1177	[IPSET_ATTR_PROTOCOL]	= { .type = NLA_U8 },
1178	[IPSET_ATTR_SETNAME]	= { .type = NLA_NUL_STRING,
1179				    .len = IPSET_MAXNAMELEN - 1 },
1180	[IPSET_ATTR_LINENO]	= { .type = NLA_U32 },
1181	[IPSET_ATTR_DATA]	= { .type = NLA_NESTED },
1182	[IPSET_ATTR_ADT]	= { .type = NLA_NESTED },
1183};
1184
1185static int
1186call_ad(struct sock *ctnl, struct sk_buff *skb, struct ip_set *set,
1187	struct nlattr *tb[], enum ipset_adt adt,
1188	u32 flags, bool use_lineno)
1189{
1190	int ret;
1191	u32 lineno = 0;
1192	bool eexist = flags & IPSET_FLAG_EXIST, retried = false;
1193
1194	do {
1195		write_lock_bh(&set->lock);
1196		ret = set->variant->uadt(set, tb, adt, &lineno, flags, retried);
1197		write_unlock_bh(&set->lock);
1198		retried = true;
1199	} while (ret == -EAGAIN &&
1200		 set->variant->resize &&
1201		 (ret = set->variant->resize(set, retried)) == 0);
1202
1203	if (!ret || (ret == -IPSET_ERR_EXIST && eexist))
1204		return 0;
1205	if (lineno && use_lineno) {
1206		/* Error in restore/batch mode: send back lineno */
1207		struct nlmsghdr *rep, *nlh = nlmsg_hdr(skb);
1208		struct sk_buff *skb2;
1209		struct nlmsgerr *errmsg;
1210		size_t payload = sizeof(*errmsg) + nlmsg_len(nlh);
1211		int min_len = NLMSG_SPACE(sizeof(struct nfgenmsg));
1212		struct nlattr *cda[IPSET_ATTR_CMD_MAX+1];
1213		struct nlattr *cmdattr;
1214		u32 *errline;
1215
1216		skb2 = nlmsg_new(payload, GFP_KERNEL);
1217		if (skb2 == NULL)
1218			return -ENOMEM;
1219		rep = __nlmsg_put(skb2, NETLINK_CB(skb).pid,
1220				  nlh->nlmsg_seq, NLMSG_ERROR, payload, 0);
1221		errmsg = nlmsg_data(rep);
1222		errmsg->error = ret;
1223		memcpy(&errmsg->msg, nlh, nlh->nlmsg_len);
1224		cmdattr = (void *)&errmsg->msg + min_len;
1225
1226		nla_parse(cda, IPSET_ATTR_CMD_MAX,
1227			  cmdattr, nlh->nlmsg_len - min_len,
1228			  ip_set_adt_policy);
1229
1230		errline = nla_data(cda[IPSET_ATTR_LINENO]);
1231
1232		*errline = lineno;
1233
1234		netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);
1235		/* Signal netlink not to send its ACK/errmsg.  */
1236		return -EINTR;
1237	}
1238
1239	return ret;
1240}
1241
1242static int
1243ip_set_uadd(struct sock *ctnl, struct sk_buff *skb,
1244	    const struct nlmsghdr *nlh,
1245	    const struct nlattr * const attr[])
1246{
1247	struct ip_set *set;
1248	struct nlattr *tb[IPSET_ATTR_ADT_MAX+1] = {};
1249	const struct nlattr *nla;
1250	u32 flags = flag_exist(nlh);
1251	bool use_lineno;
1252	int ret = 0;
1253
1254	if (unlikely(protocol_failed(attr) ||
1255		     attr[IPSET_ATTR_SETNAME] == NULL ||
1256		     !((attr[IPSET_ATTR_DATA] != NULL) ^
1257		       (attr[IPSET_ATTR_ADT] != NULL)) ||
1258		     (attr[IPSET_ATTR_DATA] != NULL &&
1259		      !flag_nested(attr[IPSET_ATTR_DATA])) ||
1260		     (attr[IPSET_ATTR_ADT] != NULL &&
1261		      (!flag_nested(attr[IPSET_ATTR_ADT]) ||
1262		       attr[IPSET_ATTR_LINENO] == NULL))))
1263		return -IPSET_ERR_PROTOCOL;
1264
1265	set = find_set(nla_data(attr[IPSET_ATTR_SETNAME]));
1266	if (set == NULL)
1267		return -ENOENT;
1268
1269	use_lineno = !!attr[IPSET_ATTR_LINENO];
1270	if (attr[IPSET_ATTR_DATA]) {
1271		if (nla_parse_nested(tb, IPSET_ATTR_ADT_MAX,
1272				     attr[IPSET_ATTR_DATA],
1273				     set->type->adt_policy))
1274			return -IPSET_ERR_PROTOCOL;
1275		ret = call_ad(ctnl, skb, set, tb, IPSET_ADD, flags,
1276			      use_lineno);
1277	} else {
1278		int nla_rem;
1279
1280		nla_for_each_nested(nla, attr[IPSET_ATTR_ADT], nla_rem) {
1281			memset(tb, 0, sizeof(tb));
1282			if (nla_type(nla) != IPSET_ATTR_DATA ||
1283			    !flag_nested(nla) ||
1284			    nla_parse_nested(tb, IPSET_ATTR_ADT_MAX, nla,
1285					     set->type->adt_policy))
1286				return -IPSET_ERR_PROTOCOL;
1287			ret = call_ad(ctnl, skb, set, tb, IPSET_ADD,
1288				      flags, use_lineno);
1289			if (ret < 0)
1290				return ret;
1291		}
1292	}
1293	return ret;
1294}
1295
1296static int
1297ip_set_udel(struct sock *ctnl, struct sk_buff *skb,
1298	    const struct nlmsghdr *nlh,
1299	    const struct nlattr * const attr[])
1300{
1301	struct ip_set *set;
1302	struct nlattr *tb[IPSET_ATTR_ADT_MAX+1] = {};
1303	const struct nlattr *nla;
1304	u32 flags = flag_exist(nlh);
1305	bool use_lineno;
1306	int ret = 0;
1307
1308	if (unlikely(protocol_failed(attr) ||
1309		     attr[IPSET_ATTR_SETNAME] == NULL ||
1310		     !((attr[IPSET_ATTR_DATA] != NULL) ^
1311		       (attr[IPSET_ATTR_ADT] != NULL)) ||
1312		     (attr[IPSET_ATTR_DATA] != NULL &&
1313		      !flag_nested(attr[IPSET_ATTR_DATA])) ||
1314		     (attr[IPSET_ATTR_ADT] != NULL &&
1315		      (!flag_nested(attr[IPSET_ATTR_ADT]) ||
1316		       attr[IPSET_ATTR_LINENO] == NULL))))
1317		return -IPSET_ERR_PROTOCOL;
1318
1319	set = find_set(nla_data(attr[IPSET_ATTR_SETNAME]));
1320	if (set == NULL)
1321		return -ENOENT;
1322
1323	use_lineno = !!attr[IPSET_ATTR_LINENO];
1324	if (attr[IPSET_ATTR_DATA]) {
1325		if (nla_parse_nested(tb, IPSET_ATTR_ADT_MAX,
1326				     attr[IPSET_ATTR_DATA],
1327				     set->type->adt_policy))
1328			return -IPSET_ERR_PROTOCOL;
1329		ret = call_ad(ctnl, skb, set, tb, IPSET_DEL, flags,
1330			      use_lineno);
1331	} else {
1332		int nla_rem;
1333
1334		nla_for_each_nested(nla, attr[IPSET_ATTR_ADT], nla_rem) {
1335			memset(tb, 0, sizeof(*tb));
1336			if (nla_type(nla) != IPSET_ATTR_DATA ||
1337			    !flag_nested(nla) ||
1338			    nla_parse_nested(tb, IPSET_ATTR_ADT_MAX, nla,
1339					     set->type->adt_policy))
1340				return -IPSET_ERR_PROTOCOL;
1341			ret = call_ad(ctnl, skb, set, tb, IPSET_DEL,
1342				      flags, use_lineno);
1343			if (ret < 0)
1344				return ret;
1345		}
1346	}
1347	return ret;
1348}
1349
1350static int
1351ip_set_utest(struct sock *ctnl, struct sk_buff *skb,
1352	     const struct nlmsghdr *nlh,
1353	     const struct nlattr * const attr[])
1354{
1355	struct ip_set *set;
1356	struct nlattr *tb[IPSET_ATTR_ADT_MAX+1] = {};
1357	int ret = 0;
1358
1359	if (unlikely(protocol_failed(attr) ||
1360		     attr[IPSET_ATTR_SETNAME] == NULL ||
1361		     attr[IPSET_ATTR_DATA] == NULL ||
1362		     !flag_nested(attr[IPSET_ATTR_DATA])))
1363		return -IPSET_ERR_PROTOCOL;
1364
1365	set = find_set(nla_data(attr[IPSET_ATTR_SETNAME]));
1366	if (set == NULL)
1367		return -ENOENT;
1368
1369	if (nla_parse_nested(tb, IPSET_ATTR_ADT_MAX, attr[IPSET_ATTR_DATA],
1370			     set->type->adt_policy))
1371		return -IPSET_ERR_PROTOCOL;
1372
1373	read_lock_bh(&set->lock);
1374	ret = set->variant->uadt(set, tb, IPSET_TEST, NULL, 0, 0);
1375	read_unlock_bh(&set->lock);
1376	/* Userspace can't trigger element to be re-added */
1377	if (ret == -EAGAIN)
1378		ret = 1;
1379
1380	return ret < 0 ? ret : ret > 0 ? 0 : -IPSET_ERR_EXIST;
1381}
1382
1383/* Get headed data of a set */
1384
1385static int
1386ip_set_header(struct sock *ctnl, struct sk_buff *skb,
1387	      const struct nlmsghdr *nlh,
1388	      const struct nlattr * const attr[])
1389{
1390	const struct ip_set *set;
1391	struct sk_buff *skb2;
1392	struct nlmsghdr *nlh2;
1393	ip_set_id_t index;
1394	int ret = 0;
1395
1396	if (unlikely(protocol_failed(attr) ||
1397		     attr[IPSET_ATTR_SETNAME] == NULL))
1398		return -IPSET_ERR_PROTOCOL;
1399
1400	index = find_set_id(nla_data(attr[IPSET_ATTR_SETNAME]));
1401	if (index == IPSET_INVALID_ID)
1402		return -ENOENT;
1403	set = ip_set_list[index];
1404
1405	skb2 = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
1406	if (skb2 == NULL)
1407		return -ENOMEM;
1408
1409	nlh2 = start_msg(skb2, NETLINK_CB(skb).pid, nlh->nlmsg_seq, 0,
1410			 IPSET_CMD_HEADER);
1411	if (!nlh2)
1412		goto nlmsg_failure;
1413	NLA_PUT_U8(skb2, IPSET_ATTR_PROTOCOL, IPSET_PROTOCOL);
1414	NLA_PUT_STRING(skb2, IPSET_ATTR_SETNAME, set->name);
1415	NLA_PUT_STRING(skb2, IPSET_ATTR_TYPENAME, set->type->name);
1416	NLA_PUT_U8(skb2, IPSET_ATTR_FAMILY, set->family);
1417	NLA_PUT_U8(skb2, IPSET_ATTR_REVISION, set->revision);
1418	nlmsg_end(skb2, nlh2);
1419
1420	ret = netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);
1421	if (ret < 0)
1422		return ret;
1423
1424	return 0;
1425
1426nla_put_failure:
1427	nlmsg_cancel(skb2, nlh2);
1428nlmsg_failure:
1429	kfree_skb(skb2);
1430	return -EMSGSIZE;
1431}
1432
1433/* Get type data */
1434
1435static const struct nla_policy ip_set_type_policy[IPSET_ATTR_CMD_MAX + 1] = {
1436	[IPSET_ATTR_PROTOCOL]	= { .type = NLA_U8 },
1437	[IPSET_ATTR_TYPENAME]	= { .type = NLA_NUL_STRING,
1438				    .len = IPSET_MAXNAMELEN - 1 },
1439	[IPSET_ATTR_FAMILY]	= { .type = NLA_U8 },
1440};
1441
1442static int
1443ip_set_type(struct sock *ctnl, struct sk_buff *skb,
1444	    const struct nlmsghdr *nlh,
1445	    const struct nlattr * const attr[])
1446{
1447	struct sk_buff *skb2;
1448	struct nlmsghdr *nlh2;
1449	u8 family, min, max;
1450	const char *typename;
1451	int ret = 0;
1452
1453	if (unlikely(protocol_failed(attr) ||
1454		     attr[IPSET_ATTR_TYPENAME] == NULL ||
1455		     attr[IPSET_ATTR_FAMILY] == NULL))
1456		return -IPSET_ERR_PROTOCOL;
1457
1458	family = nla_get_u8(attr[IPSET_ATTR_FAMILY]);
1459	typename = nla_data(attr[IPSET_ATTR_TYPENAME]);
1460	ret = find_set_type_minmax(typename, family, &min, &max);
1461	if (ret)
1462		return ret;
1463
1464	skb2 = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
1465	if (skb2 == NULL)
1466		return -ENOMEM;
1467
1468	nlh2 = start_msg(skb2, NETLINK_CB(skb).pid, nlh->nlmsg_seq, 0,
1469			 IPSET_CMD_TYPE);
1470	if (!nlh2)
1471		goto nlmsg_failure;
1472	NLA_PUT_U8(skb2, IPSET_ATTR_PROTOCOL, IPSET_PROTOCOL);
1473	NLA_PUT_STRING(skb2, IPSET_ATTR_TYPENAME, typename);
1474	NLA_PUT_U8(skb2, IPSET_ATTR_FAMILY, family);
1475	NLA_PUT_U8(skb2, IPSET_ATTR_REVISION, max);
1476	NLA_PUT_U8(skb2, IPSET_ATTR_REVISION_MIN, min);
1477	nlmsg_end(skb2, nlh2);
1478
1479	pr_debug("Send TYPE, nlmsg_len: %u\n", nlh2->nlmsg_len);
1480	ret = netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);
1481	if (ret < 0)
1482		return ret;
1483
1484	return 0;
1485
1486nla_put_failure:
1487	nlmsg_cancel(skb2, nlh2);
1488nlmsg_failure:
1489	kfree_skb(skb2);
1490	return -EMSGSIZE;
1491}
1492
1493/* Get protocol version */
1494
1495static const struct nla_policy
1496ip_set_protocol_policy[IPSET_ATTR_CMD_MAX + 1] = {
1497	[IPSET_ATTR_PROTOCOL]	= { .type = NLA_U8 },
1498};
1499
1500static int
1501ip_set_protocol(struct sock *ctnl, struct sk_buff *skb,
1502		const struct nlmsghdr *nlh,
1503		const struct nlattr * const attr[])
1504{
1505	struct sk_buff *skb2;
1506	struct nlmsghdr *nlh2;
1507	int ret = 0;
1508
1509	if (unlikely(attr[IPSET_ATTR_PROTOCOL] == NULL))
1510		return -IPSET_ERR_PROTOCOL;
1511
1512	skb2 = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
1513	if (skb2 == NULL)
1514		return -ENOMEM;
1515
1516	nlh2 = start_msg(skb2, NETLINK_CB(skb).pid, nlh->nlmsg_seq, 0,
1517			 IPSET_CMD_PROTOCOL);
1518	if (!nlh2)
1519		goto nlmsg_failure;
1520	NLA_PUT_U8(skb2, IPSET_ATTR_PROTOCOL, IPSET_PROTOCOL);
1521	nlmsg_end(skb2, nlh2);
1522
1523	ret = netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);
1524	if (ret < 0)
1525		return ret;
1526
1527	return 0;
1528
1529nla_put_failure:
1530	nlmsg_cancel(skb2, nlh2);
1531nlmsg_failure:
1532	kfree_skb(skb2);
1533	return -EMSGSIZE;
1534}
1535
1536static const struct nfnl_callback ip_set_netlink_subsys_cb[IPSET_MSG_MAX] = {
1537	[IPSET_CMD_CREATE]	= {
1538		.call		= ip_set_create,
1539		.attr_count	= IPSET_ATTR_CMD_MAX,
1540		.policy		= ip_set_create_policy,
1541	},
1542	[IPSET_CMD_DESTROY]	= {
1543		.call		= ip_set_destroy,
1544		.attr_count	= IPSET_ATTR_CMD_MAX,
1545		.policy		= ip_set_setname_policy,
1546	},
1547	[IPSET_CMD_FLUSH]	= {
1548		.call		= ip_set_flush,
1549		.attr_count	= IPSET_ATTR_CMD_MAX,
1550		.policy		= ip_set_setname_policy,
1551	},
1552	[IPSET_CMD_RENAME]	= {
1553		.call		= ip_set_rename,
1554		.attr_count	= IPSET_ATTR_CMD_MAX,
1555		.policy		= ip_set_setname2_policy,
1556	},
1557	[IPSET_CMD_SWAP]	= {
1558		.call		= ip_set_swap,
1559		.attr_count	= IPSET_ATTR_CMD_MAX,
1560		.policy		= ip_set_setname2_policy,
1561	},
1562	[IPSET_CMD_LIST]	= {
1563		.call		= ip_set_dump,
1564		.attr_count	= IPSET_ATTR_CMD_MAX,
1565		.policy		= ip_set_setname_policy,
1566	},
1567	[IPSET_CMD_SAVE]	= {
1568		.call		= ip_set_dump,
1569		.attr_count	= IPSET_ATTR_CMD_MAX,
1570		.policy		= ip_set_setname_policy,
1571	},
1572	[IPSET_CMD_ADD]	= {
1573		.call		= ip_set_uadd,
1574		.attr_count	= IPSET_ATTR_CMD_MAX,
1575		.policy		= ip_set_adt_policy,
1576	},
1577	[IPSET_CMD_DEL]	= {
1578		.call		= ip_set_udel,
1579		.attr_count	= IPSET_ATTR_CMD_MAX,
1580		.policy		= ip_set_adt_policy,
1581	},
1582	[IPSET_CMD_TEST]	= {
1583		.call		= ip_set_utest,
1584		.attr_count	= IPSET_ATTR_CMD_MAX,
1585		.policy		= ip_set_adt_policy,
1586	},
1587	[IPSET_CMD_HEADER]	= {
1588		.call		= ip_set_header,
1589		.attr_count	= IPSET_ATTR_CMD_MAX,
1590		.policy		= ip_set_setname_policy,
1591	},
1592	[IPSET_CMD_TYPE]	= {
1593		.call		= ip_set_type,
1594		.attr_count	= IPSET_ATTR_CMD_MAX,
1595		.policy		= ip_set_type_policy,
1596	},
1597	[IPSET_CMD_PROTOCOL]	= {
1598		.call		= ip_set_protocol,
1599		.attr_count	= IPSET_ATTR_CMD_MAX,
1600		.policy		= ip_set_protocol_policy,
1601	},
1602};
1603
1604static struct nfnetlink_subsystem ip_set_netlink_subsys __read_mostly = {
1605	.name		= "ip_set",
1606	.subsys_id	= NFNL_SUBSYS_IPSET,
1607	.cb_count	= IPSET_MSG_MAX,
1608	.cb		= ip_set_netlink_subsys_cb,
1609};
1610
1611/* Interface to iptables/ip6tables */
1612
1613static int
1614ip_set_sockfn_get(struct sock *sk, int optval, void __user *user, int *len)
1615{
1616	unsigned *op;
1617	void *data;
1618	int copylen = *len, ret = 0;
1619
1620	if (!capable(CAP_NET_ADMIN))
1621		return -EPERM;
1622	if (optval != SO_IP_SET)
1623		return -EBADF;
1624	if (*len < sizeof(unsigned))
1625		return -EINVAL;
1626
1627	data = vmalloc(*len);
1628	if (!data)
1629		return -ENOMEM;
1630	if (copy_from_user(data, user, *len) != 0) {
1631		ret = -EFAULT;
1632		goto done;
1633	}
1634	op = (unsigned *) data;
1635
1636	if (*op < IP_SET_OP_VERSION) {
1637		/* Check the version at the beginning of operations */
1638		struct ip_set_req_version *req_version = data;
1639		if (req_version->version != IPSET_PROTOCOL) {
1640			ret = -EPROTO;
1641			goto done;
1642		}
1643	}
1644
1645	switch (*op) {
1646	case IP_SET_OP_VERSION: {
1647		struct ip_set_req_version *req_version = data;
1648
1649		if (*len != sizeof(struct ip_set_req_version)) {
1650			ret = -EINVAL;
1651			goto done;
1652		}
1653
1654		req_version->version = IPSET_PROTOCOL;
1655		ret = copy_to_user(user, req_version,
1656				   sizeof(struct ip_set_req_version));
1657		goto done;
1658	}
1659	case IP_SET_OP_GET_BYNAME: {
1660		struct ip_set_req_get_set *req_get = data;
1661
1662		if (*len != sizeof(struct ip_set_req_get_set)) {
1663			ret = -EINVAL;
1664			goto done;
1665		}
1666		req_get->set.name[IPSET_MAXNAMELEN - 1] = '\0';
1667		nfnl_lock();
1668		req_get->set.index = find_set_id(req_get->set.name);
1669		nfnl_unlock();
1670		goto copy;
1671	}
1672	case IP_SET_OP_GET_BYINDEX: {
1673		struct ip_set_req_get_set *req_get = data;
1674
1675		if (*len != sizeof(struct ip_set_req_get_set) ||
1676		    req_get->set.index >= ip_set_max) {
1677			ret = -EINVAL;
1678			goto done;
1679		}
1680		nfnl_lock();
1681		strncpy(req_get->set.name,
1682			ip_set_list[req_get->set.index]
1683				? ip_set_list[req_get->set.index]->name : "",
1684			IPSET_MAXNAMELEN);
1685		nfnl_unlock();
1686		goto copy;
1687	}
1688	default:
1689		ret = -EBADMSG;
1690		goto done;
1691	}	/* end of switch(op) */
1692
1693copy:
1694	ret = copy_to_user(user, data, copylen);
1695
1696done:
1697	vfree(data);
1698	if (ret > 0)
1699		ret = 0;
1700	return ret;
1701}
1702
1703static struct nf_sockopt_ops so_set __read_mostly = {
1704	.pf		= PF_INET,
1705	.get_optmin	= SO_IP_SET,
1706	.get_optmax	= SO_IP_SET + 1,
1707	.get		= &ip_set_sockfn_get,
1708	.owner		= THIS_MODULE,
1709};
1710
1711static int __init
1712ip_set_init(void)
1713{
1714	int ret;
1715
1716	if (max_sets)
1717		ip_set_max = max_sets;
1718	if (ip_set_max >= IPSET_INVALID_ID)
1719		ip_set_max = IPSET_INVALID_ID - 1;
1720
1721	ip_set_list = kzalloc(sizeof(struct ip_set *) * ip_set_max,
1722			      GFP_KERNEL);
1723	if (!ip_set_list)
1724		return -ENOMEM;
1725
1726	ret = nfnetlink_subsys_register(&ip_set_netlink_subsys);
1727	if (ret != 0) {
1728		pr_err("ip_set: cannot register with nfnetlink.\n");
1729		kfree(ip_set_list);
1730		return ret;
1731	}
1732	ret = nf_register_sockopt(&so_set);
1733	if (ret != 0) {
1734		pr_err("SO_SET registry failed: %d\n", ret);
1735		nfnetlink_subsys_unregister(&ip_set_netlink_subsys);
1736		kfree(ip_set_list);
1737		return ret;
1738	}
1739
1740	pr_notice("ip_set: protocol %u\n", IPSET_PROTOCOL);
1741	return 0;
1742}
1743
1744static void __exit
1745ip_set_fini(void)
1746{
1747	/* There can't be any existing set */
1748	nf_unregister_sockopt(&so_set);
1749	nfnetlink_subsys_unregister(&ip_set_netlink_subsys);
1750	kfree(ip_set_list);
1751	pr_debug("these are the famous last words\n");
1752}
1753
1754module_init(ip_set_init);
1755module_exit(ip_set_fini);
1756