xt_set.c revision b66554cf03fe866b3fb7b9f40f430b8ba09f41c8
1/* Copyright (C) 2000-2002 Joakim Axelsson <gozem@linux.nu>
2 *                         Patrick Schaaf <bof@bof.de>
3 *                         Martin Josefsson <gandalf@wlug.westbo.se>
4 * Copyright (C) 2003-2011 Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10
11/* Kernel module which implements the set match and SET target
12 * for netfilter/iptables. */
13
14#include <linux/module.h>
15#include <linux/skbuff.h>
16#include <linux/version.h>
17
18#include <linux/netfilter/x_tables.h>
19#include <linux/netfilter/xt_set.h>
20
21MODULE_LICENSE("GPL");
22MODULE_AUTHOR("Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>");
23MODULE_DESCRIPTION("Xtables: IP set match and target module");
24MODULE_ALIAS("xt_SET");
25MODULE_ALIAS("ipt_set");
26MODULE_ALIAS("ip6t_set");
27MODULE_ALIAS("ipt_SET");
28MODULE_ALIAS("ip6t_SET");
29
30static inline int
31match_set(ip_set_id_t index, const struct sk_buff *skb,
32	  const struct xt_action_param *par,
33	  const struct ip_set_adt_opt *opt, int inv)
34{
35	if (ip_set_test(index, skb, par, opt))
36		inv = !inv;
37	return inv;
38}
39
40#define ADT_OPT(n, f, d, fs, cfs, t) 	\
41const struct ip_set_adt_opt n = {	\
42	.family	= f,			\
43	.dim = d,			\
44	.flags = fs,			\
45	.cmdflags = cfs,		\
46	.timeout = t,			\
47}
48
49/* Revision 0 interface: backward compatible with netfilter/iptables */
50
51static bool
52set_match_v0(const struct sk_buff *skb, struct xt_action_param *par)
53{
54	const struct xt_set_info_match_v0 *info = par->matchinfo;
55	ADT_OPT(opt, par->family, info->match_set.u.compat.dim,
56		info->match_set.u.compat.flags, 0, UINT_MAX);
57
58	return match_set(info->match_set.index, skb, par, &opt,
59			 info->match_set.u.compat.flags & IPSET_INV_MATCH);
60}
61
62static void
63compat_flags(struct xt_set_info_v0 *info)
64{
65	u_int8_t i;
66
67	/* Fill out compatibility data according to enum ip_set_kopt */
68	info->u.compat.dim = IPSET_DIM_ZERO;
69	if (info->u.flags[0] & IPSET_MATCH_INV)
70		info->u.compat.flags |= IPSET_INV_MATCH;
71	for (i = 0; i < IPSET_DIM_MAX-1 && info->u.flags[i]; i++) {
72		info->u.compat.dim++;
73		if (info->u.flags[i] & IPSET_SRC)
74			info->u.compat.flags |= (1<<info->u.compat.dim);
75	}
76}
77
78static int
79set_match_v0_checkentry(const struct xt_mtchk_param *par)
80{
81	struct xt_set_info_match_v0 *info = par->matchinfo;
82	ip_set_id_t index;
83
84	index = ip_set_nfnl_get_byindex(info->match_set.index);
85
86	if (index == IPSET_INVALID_ID) {
87		pr_warning("Cannot find set indentified by id %u to match\n",
88			   info->match_set.index);
89		return -ENOENT;
90	}
91	if (info->match_set.u.flags[IPSET_DIM_MAX-1] != 0) {
92		pr_warning("Protocol error: set match dimension "
93			   "is over the limit!\n");
94		ip_set_nfnl_put(info->match_set.index);
95		return -ERANGE;
96	}
97
98	/* Fill out compatibility data */
99	compat_flags(&info->match_set);
100
101	return 0;
102}
103
104static void
105set_match_v0_destroy(const struct xt_mtdtor_param *par)
106{
107	struct xt_set_info_match_v0 *info = par->matchinfo;
108
109	ip_set_nfnl_put(info->match_set.index);
110}
111
112static unsigned int
113set_target_v0(struct sk_buff *skb, const struct xt_action_param *par)
114{
115	const struct xt_set_info_target_v0 *info = par->targinfo;
116	ADT_OPT(add_opt, par->family, info->add_set.u.compat.dim,
117		info->add_set.u.compat.flags, 0, UINT_MAX);
118	ADT_OPT(del_opt, par->family, info->del_set.u.compat.dim,
119		info->del_set.u.compat.flags, 0, UINT_MAX);
120
121	if (info->add_set.index != IPSET_INVALID_ID)
122		ip_set_add(info->add_set.index, skb, par, &add_opt);
123	if (info->del_set.index != IPSET_INVALID_ID)
124		ip_set_del(info->del_set.index, skb, par, &del_opt);
125
126	return XT_CONTINUE;
127}
128
129static int
130set_target_v0_checkentry(const struct xt_tgchk_param *par)
131{
132	struct xt_set_info_target_v0 *info = par->targinfo;
133	ip_set_id_t index;
134
135	if (info->add_set.index != IPSET_INVALID_ID) {
136		index = ip_set_nfnl_get_byindex(info->add_set.index);
137		if (index == IPSET_INVALID_ID) {
138			pr_warning("Cannot find add_set index %u as target\n",
139				   info->add_set.index);
140			return -ENOENT;
141		}
142	}
143
144	if (info->del_set.index != IPSET_INVALID_ID) {
145		index = ip_set_nfnl_get_byindex(info->del_set.index);
146		if (index == IPSET_INVALID_ID) {
147			pr_warning("Cannot find del_set index %u as target\n",
148				   info->del_set.index);
149			if (info->add_set.index != IPSET_INVALID_ID)
150				ip_set_nfnl_put(info->add_set.index);
151			return -ENOENT;
152		}
153	}
154	if (info->add_set.u.flags[IPSET_DIM_MAX-1] != 0 ||
155	    info->del_set.u.flags[IPSET_DIM_MAX-1] != 0) {
156		pr_warning("Protocol error: SET target dimension "
157			   "is over the limit!\n");
158		if (info->add_set.index != IPSET_INVALID_ID)
159			ip_set_nfnl_put(info->add_set.index);
160		if (info->del_set.index != IPSET_INVALID_ID)
161			ip_set_nfnl_put(info->del_set.index);
162		return -ERANGE;
163	}
164
165	/* Fill out compatibility data */
166	compat_flags(&info->add_set);
167	compat_flags(&info->del_set);
168
169	return 0;
170}
171
172static void
173set_target_v0_destroy(const struct xt_tgdtor_param *par)
174{
175	const struct xt_set_info_target_v0 *info = par->targinfo;
176
177	if (info->add_set.index != IPSET_INVALID_ID)
178		ip_set_nfnl_put(info->add_set.index);
179	if (info->del_set.index != IPSET_INVALID_ID)
180		ip_set_nfnl_put(info->del_set.index);
181}
182
183/* Revision 1 match and target */
184
185static bool
186set_match_v1(const struct sk_buff *skb, struct xt_action_param *par)
187{
188	const struct xt_set_info_match_v1 *info = par->matchinfo;
189	ADT_OPT(opt, par->family, info->match_set.dim,
190		info->match_set.flags, 0, UINT_MAX);
191
192	return match_set(info->match_set.index, skb, par, &opt,
193			 info->match_set.flags & IPSET_INV_MATCH);
194}
195
196static int
197set_match_v1_checkentry(const struct xt_mtchk_param *par)
198{
199	struct xt_set_info_match_v1 *info = par->matchinfo;
200	ip_set_id_t index;
201
202	index = ip_set_nfnl_get_byindex(info->match_set.index);
203
204	if (index == IPSET_INVALID_ID) {
205		pr_warning("Cannot find set indentified by id %u to match\n",
206			   info->match_set.index);
207		return -ENOENT;
208	}
209	if (info->match_set.dim > IPSET_DIM_MAX) {
210		pr_warning("Protocol error: set match dimension "
211			   "is over the limit!\n");
212		ip_set_nfnl_put(info->match_set.index);
213		return -ERANGE;
214	}
215
216	return 0;
217}
218
219static void
220set_match_v1_destroy(const struct xt_mtdtor_param *par)
221{
222	struct xt_set_info_match_v1 *info = par->matchinfo;
223
224	ip_set_nfnl_put(info->match_set.index);
225}
226
227static unsigned int
228set_target_v1(struct sk_buff *skb, const struct xt_action_param *par)
229{
230	const struct xt_set_info_target_v1 *info = par->targinfo;
231	ADT_OPT(add_opt, par->family, info->add_set.dim,
232		info->add_set.flags, 0, UINT_MAX);
233	ADT_OPT(del_opt, par->family, info->del_set.dim,
234		info->del_set.flags, 0, UINT_MAX);
235
236	if (info->add_set.index != IPSET_INVALID_ID)
237		ip_set_add(info->add_set.index, skb, par, &add_opt);
238	if (info->del_set.index != IPSET_INVALID_ID)
239		ip_set_del(info->del_set.index, skb, par, &del_opt);
240
241	return XT_CONTINUE;
242}
243
244static int
245set_target_v1_checkentry(const struct xt_tgchk_param *par)
246{
247	const struct xt_set_info_target_v1 *info = par->targinfo;
248	ip_set_id_t index;
249
250	if (info->add_set.index != IPSET_INVALID_ID) {
251		index = ip_set_nfnl_get_byindex(info->add_set.index);
252		if (index == IPSET_INVALID_ID) {
253			pr_warning("Cannot find add_set index %u as target\n",
254				   info->add_set.index);
255			return -ENOENT;
256		}
257	}
258
259	if (info->del_set.index != IPSET_INVALID_ID) {
260		index = ip_set_nfnl_get_byindex(info->del_set.index);
261		if (index == IPSET_INVALID_ID) {
262			pr_warning("Cannot find del_set index %u as target\n",
263				   info->del_set.index);
264			if (info->add_set.index != IPSET_INVALID_ID)
265				ip_set_nfnl_put(info->add_set.index);
266			return -ENOENT;
267		}
268	}
269	if (info->add_set.dim > IPSET_DIM_MAX ||
270	    info->del_set.dim > IPSET_DIM_MAX) {
271		pr_warning("Protocol error: SET target dimension "
272			   "is over the limit!\n");
273		if (info->add_set.index != IPSET_INVALID_ID)
274			ip_set_nfnl_put(info->add_set.index);
275		if (info->del_set.index != IPSET_INVALID_ID)
276			ip_set_nfnl_put(info->del_set.index);
277		return -ERANGE;
278	}
279
280	return 0;
281}
282
283static void
284set_target_v1_destroy(const struct xt_tgdtor_param *par)
285{
286	const struct xt_set_info_target_v1 *info = par->targinfo;
287
288	if (info->add_set.index != IPSET_INVALID_ID)
289		ip_set_nfnl_put(info->add_set.index);
290	if (info->del_set.index != IPSET_INVALID_ID)
291		ip_set_nfnl_put(info->del_set.index);
292}
293
294/* Revision 2 target */
295
296static unsigned int
297set_target_v2(struct sk_buff *skb, const struct xt_action_param *par)
298{
299	const struct xt_set_info_target_v2 *info = par->targinfo;
300	ADT_OPT(add_opt, par->family, info->add_set.dim,
301		info->add_set.flags, info->flags, info->timeout);
302	ADT_OPT(del_opt, par->family, info->del_set.dim,
303		info->del_set.flags, 0, UINT_MAX);
304
305	if (info->add_set.index != IPSET_INVALID_ID)
306		ip_set_add(info->add_set.index, skb, par, &add_opt);
307	if (info->del_set.index != IPSET_INVALID_ID)
308		ip_set_del(info->del_set.index, skb, par, &del_opt);
309
310	return XT_CONTINUE;
311}
312
313#define set_target_v2_checkentry	set_target_v1_checkentry
314#define set_target_v2_destroy		set_target_v1_destroy
315
316static struct xt_match set_matches[] __read_mostly = {
317	{
318		.name		= "set",
319		.family		= NFPROTO_IPV4,
320		.revision	= 0,
321		.match		= set_match_v0,
322		.matchsize	= sizeof(struct xt_set_info_match_v0),
323		.checkentry	= set_match_v0_checkentry,
324		.destroy	= set_match_v0_destroy,
325		.me		= THIS_MODULE
326	},
327	{
328		.name		= "set",
329		.family		= NFPROTO_IPV4,
330		.revision	= 1,
331		.match		= set_match_v1,
332		.matchsize	= sizeof(struct xt_set_info_match_v1),
333		.checkentry	= set_match_v1_checkentry,
334		.destroy	= set_match_v1_destroy,
335		.me		= THIS_MODULE
336	},
337	{
338		.name		= "set",
339		.family		= NFPROTO_IPV6,
340		.revision	= 1,
341		.match		= set_match_v1,
342		.matchsize	= sizeof(struct xt_set_info_match_v1),
343		.checkentry	= set_match_v1_checkentry,
344		.destroy	= set_match_v1_destroy,
345		.me		= THIS_MODULE
346	},
347};
348
349static struct xt_target set_targets[] __read_mostly = {
350	{
351		.name		= "SET",
352		.revision	= 0,
353		.family		= NFPROTO_IPV4,
354		.target		= set_target_v0,
355		.targetsize	= sizeof(struct xt_set_info_target_v0),
356		.checkentry	= set_target_v0_checkentry,
357		.destroy	= set_target_v0_destroy,
358		.me		= THIS_MODULE
359	},
360	{
361		.name		= "SET",
362		.revision	= 1,
363		.family		= NFPROTO_IPV4,
364		.target		= set_target_v1,
365		.targetsize	= sizeof(struct xt_set_info_target_v1),
366		.checkentry	= set_target_v1_checkentry,
367		.destroy	= set_target_v1_destroy,
368		.me		= THIS_MODULE
369	},
370	{
371		.name		= "SET",
372		.revision	= 1,
373		.family		= NFPROTO_IPV6,
374		.target		= set_target_v1,
375		.targetsize	= sizeof(struct xt_set_info_target_v1),
376		.checkentry	= set_target_v1_checkentry,
377		.destroy	= set_target_v1_destroy,
378		.me		= THIS_MODULE
379	},
380	{
381		.name		= "SET",
382		.revision	= 2,
383		.family		= NFPROTO_IPV4,
384		.target		= set_target_v2,
385		.targetsize	= sizeof(struct xt_set_info_target_v2),
386		.checkentry	= set_target_v2_checkentry,
387		.destroy	= set_target_v2_destroy,
388		.me		= THIS_MODULE
389	},
390	{
391		.name		= "SET",
392		.revision	= 2,
393		.family		= NFPROTO_IPV6,
394		.target		= set_target_v2,
395		.targetsize	= sizeof(struct xt_set_info_target_v2),
396		.checkentry	= set_target_v2_checkentry,
397		.destroy	= set_target_v2_destroy,
398		.me		= THIS_MODULE
399	},
400};
401
402static int __init xt_set_init(void)
403{
404	int ret = xt_register_matches(set_matches, ARRAY_SIZE(set_matches));
405
406	if (!ret) {
407		ret = xt_register_targets(set_targets,
408					  ARRAY_SIZE(set_targets));
409		if (ret)
410			xt_unregister_matches(set_matches,
411					      ARRAY_SIZE(set_matches));
412	}
413	return ret;
414}
415
416static void __exit xt_set_fini(void)
417{
418	xt_unregister_matches(set_matches, ARRAY_SIZE(set_matches));
419	xt_unregister_targets(set_targets, ARRAY_SIZE(set_targets));
420}
421
422module_init(xt_set_init);
423module_exit(xt_set_fini);
424