summaryrefslogtreecommitdiffstats
path: root/kernel/net/netfilter/ipset/ip_set_bitmap_ip.c
blob: bca96990218dedeb2791d9df35727a9f47b20ea7 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
/* Copyright (C) 2000-2002 Joakim Axelsson <gozem@linux.nu>
 *                         Patrick Schaaf <bof@bof.de>
 * Copyright (C) 2003-2011 Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

/* Kernel module implementing an IP set type: the bitmap:ip type */

#include <linux/module.h>
#include <linux/ip.h>
#include <linux/skbuff.h>
#include <linux/errno.h>
#include <linux/bitops.h>
#include <linux/spinlock.h>
#include <linux/netlink.h>
#include <linux/jiffies.h>
#include <linux/timer.h>
#include <net/netlink.h>
#include <net/tcp.h>

#include <linux/netfilter/ipset/pfxlen.h>
#include <linux/netfilter/ipset/ip_set.h>
#include <linux/netfilter/ipset/ip_set_bitmap.h>
#define IP_SET_BITMAP_TIMEOUT
#include <linux/netfilter/ipset/ip_set_timeout.h>

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>");
MODULE_DESCRIPTION("bitmap:ip type of IP sets");
MODULE_ALIAS("ip_set_bitmap:ip");

/* Type structure */
struct bitmap_ip {
	void *members;		/* the set members */
	u32 first_ip;		/* host byte order, included in range */
	u32 last_ip;		/* host byte order, included in range */
	u32 elements;		/* number of max elements in the set */
	u32 hosts;		/* number of hosts in a subnet */
	size_t memsize;		/* members size */
	u8 netmask;		/* subnet netmask */
	u32 timeout;		/* timeout parameter */
	struct timer_list gc;	/* garbage collection */
};

/* Base variant */

static inline u32
ip_to_id(const struct bitmap_ip *m, u32 ip)
{
	return ((ip & ip_set_hostmask(m->netmask)) - m->first_ip)/m->hosts;
}

static int
bitmap_ip_test(struct ip_set *set, void *value, u32 timeout)
{
	const struct bitmap_ip *map = set->data;
	u16 id = *(u16 *)value;

	return !!test_bit(id, map->members);
}

static int
bitmap_ip_add(struct ip_set *set, void *value, u32 timeout)
{
	struct bitmap_ip *map = set->data;
	u16 id = *(u16 *)value;

	if (test_and_set_bit(id, map->members))
		return -IPSET_ERR_EXIST;

	return 0;
}

static int
bitmap_ip_del(struct ip_set *set, void *value, u32 timeout)
{
	struct bitmap_ip *map = set->data;
	u16 id = *(u16 *)value;

	if (!test_and_clear_bit(id, map->members))
		return -IPSET_ERR_EXIST;

	return 0;
}

static int
bitmap_ip_list(const struct ip_set *set,
	       struct sk_buff *skb, struct netlink_callback *cb)
{
	const struct bitmap_ip *map = set->data;
	struct nlattr *atd, *nested;
	u32 id, first = cb->args[2];

	atd = ipset_nest_start(skb, IPSET_ATTR_ADT);
	if (!atd)
		return -EMSGSIZE;
	for (; cb->args[2] < map->elements; cb->args[2]++) {
		id = cb->args[2];
		if (!test_bit(id, map->members))
			continue;
		nested = ipset_nest_start(skb, IPSET_ATTR_DATA);
		if (!nested) {
			if (id == first) {
				nla_nest_cancel(skb, atd);
				return -EMSGSIZE;
			} else
				goto nla_put_failure;
		}
		NLA_PUT_IPADDR4(skb, IPSET_ATTR_IP,
				htonl(map->first_ip + id * map->hosts));
		ipset_nest_end(skb, nested);
	}
	ipset_nest_end(skb, atd);
	/* Set listing finished */
	cb->args[2] = 0;
	return 0;

nla_put_failure:
	nla_nest_cancel(skb, nested);
	ipset_nest_end(skb, atd);
	if (unlikely(id == first)) {
		cb->args[2] = 0;
		return -EMSGSIZE;
	}
	return 0;
}

/* Timeout variant */

static int
bitmap_ip_ttest(struct ip_set *set, void *value, u32 timeout)
{
	const struct bitmap_ip *map = set->data;
	const unsigned long *members = map->members;
	u16 id = *(u16 *)value;

	return ip_set_timeout_test(members[id]);
}

static int
bitmap_ip_tadd(struct ip_set *set, void *value, u32 timeout)
{
	struct bitmap_ip *map = set->data;
	unsigned long *members = map->members;
	u16 id = *(u16 *)value;

	if (ip_set_timeout_test(members[id]))
		return -IPSET_ERR_EXIST;

	members[id] = ip_set_timeout_set(timeout);

	return 0;
}

static int
bitmap_ip_tdel(struct ip_set *set, void *value, u32 timeout)
{
	struct bitmap_ip *map = set->data;
	unsigned long *members = map->members;
	u16 id = *(u16 *)value;
	int ret = -IPSET_ERR_EXIST;

	if (ip_set_timeout_test(members[id]))
		ret = 0;

	members[id] = IPSET_ELEM_UNSET;
	return ret;
}

static int
bitmap_ip_tlist(const struct ip_set *set,
		struct sk_buff *skb, struct netlink_callback *cb)
{
	const struct bitmap_ip *map = set->data;
	struct nlattr *adt, *nested;
	u32 id, first = cb->args[2];
	const unsigned long *members = map->members;

	adt = ipset_nest_start(skb, IPSET_ATTR_ADT);
	if (!adt)
		return -EMSGSIZE;
	for (; cb->args[2] < map->elements; cb->args[2]++) {
		id = cb->args[2];
		if (!ip_set_timeout_test(members[id]))
			continue;
		nested = ipset_nest_start(skb, IPSET_ATTR_DATA);
		if (!nested) {
			if (id == first) {
				nla_nest_cancel(skb, adt);
				return -EMSGSIZE;
			} else
				goto nla_put_failure;
		}
		NLA_PUT_IPADDR4(skb, IPSET_ATTR_IP,
				htonl(map->first_ip + id * map->hosts));
		NLA_PUT_NET32(skb, IPSET_ATTR_TIMEOUT,
			      htonl(ip_set_timeout_get(members[id])));
		ipset_nest_end(skb, nested);
	}
	ipset_nest_end(skb, adt);

	/* Set listing finished */
	cb->args[2] = 0;

	return 0;

nla_put_failure:
	nla_nest_cancel(skb, nested);
	ipset_nest_end(skb, adt);
	if (unlikely(id == first)) {
		cb->args[2] = 0;
		return -EMSGSIZE;
	}
	return 0;
}

static int
bitmap_ip_kadt(struct ip_set *set, const struct sk_buff *skb,
	       enum ipset_adt adt, u8 pf, u8 dim, u8 flags)
{
	struct bitmap_ip *map = set->data;
	ipset_adtfn adtfn = set->variant->adt[adt];
	u32 ip;

	ip = ntohl(ip4addr(skb, flags & IPSET_DIM_ONE_SRC));
	if (ip < map->first_ip || ip > map->last_ip)
		return -IPSET_ERR_BITMAP_RANGE;

	ip = ip_to_id(map, ip);

	return adtfn(set, &ip, map->timeout);
}

static int
bitmap_ip_uadt(struct ip_set *set, struct nlattr *tb[],
	       enum ipset_adt adt, u32 *lineno, u32 flags)
{
	struct bitmap_ip *map = set->data;
	ipset_adtfn adtfn = set->variant->adt[adt];
	u32 timeout = map->timeout;
	u32 ip, ip_to, id;
	int ret = 0;

	if (unlikely(!tb[IPSET_ATTR_IP] ||
		     !ip_set_optattr_netorder(tb, IPSET_ATTR_TIMEOUT)))
		return -IPSET_ERR_PROTOCOL;

	if (tb[IPSET_ATTR_LINENO])
		*lineno = nla_get_u32(tb[IPSET_ATTR_LINENO]);

	ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP], &ip);
	if (ret)
		return ret;

	if (ip < map->first_ip || ip > map->last_ip)
		return -IPSET_ERR_BITMAP_RANGE;

	if (tb[IPSET_ATTR_TIMEOUT]) {
		if (!with_timeout(map->timeout))
			return -IPSET_ERR_TIMEOUT;
		timeout = ip_set_timeout_uget(tb[IPSET_ATTR_TIMEOUT]);
	}

	if (adt == IPSET_TEST) {
		id = ip_to_id(map, ip);
		return adtfn(set, &id, timeout);
	}

	if (tb[IPSET_ATTR_IP_TO]) {
		ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP_TO], &ip_to);
		if (ret)
			return ret;
		if (ip > ip_to) {
			swap(ip, ip_to);
			if (ip < map->first_ip)
				return -IPSET_ERR_BITMAP_RANGE;
		}
	} else if (tb[IPSET_ATTR_CIDR]) {
		u8 cidr = nla_get_u8(tb[IPSET_ATTR_CIDR]);

		if (cidr > 32)
			return -IPSET_ERR_INVALID_CIDR;
		ip &= ip_set_hostmask(cidr);
		ip_to = ip | ~ip_set_hostmask(cidr);
	} else
		ip_to = ip;

	if (ip_to > map->last_ip)
		return -IPSET_ERR_BITMAP_RANGE;

	for (; !before(ip_to, ip); ip += map->hosts) {
		id = ip_to_id(map, ip);
		ret = adtfn(set, &id, timeout);;

		if (ret && !ip_set_eexist(ret, flags))
			return ret;
		else
			ret = 0;
	}
	return ret;
}

static void
bitmap_ip_destroy(struct ip_set *set)
{
	struct bitmap_ip *map = set->data;

	if (with_timeout(map->timeout))
		del_timer_sync(&map->gc);

	ip_set_free(map->members);
	kfree(map);

	set->data = NULL;
}

static void
bitmap_ip_flush(struct ip_set *set)
{
	struct bitmap_ip *map = set->data;

	memset(map->members, 0, map->memsize);
}

static int
bitmap_ip_head(struct ip_set *set, struct sk_buff *skb)
{
	const struct bitmap_ip *map = set->data;
	struct nlattr *nested;

	nested = ipset_nest_start(skb, IPSET_ATTR_DATA);
	if (!nested)
		goto nla_put_failure;
	NLA_PUT_IPADDR4(skb, IPSET_ATTR_IP, htonl(map->first_ip));
	NLA_PUT_IPADDR4(skb, IPSET_ATTR_IP_TO, htonl(map->last_ip));
	if (map->netmask != 32)
		NLA_PUT_U8(skb, IPSET_ATTR_NETMASK, map->netmask);
	NLA_PUT_NET32(skb, IPSET_ATTR_REFERENCES,
		      htonl(atomic_read(&set->ref) - 1));
	NLA_PUT_NET32(skb, IPSET_ATTR_MEMSIZE,
		      htonl(sizeof(*map) + map->memsize));
	if (with_timeout(map->timeout))
		NLA_PUT_NET32(skb, IPSET_ATTR_TIMEOUT, htonl(map->timeout));
	ipset_nest_end(skb, nested);

	return 0;
nla_put_failure:
	return -EMSGSIZE;
}

static bool
bitmap_ip_same_set(const struct ip_set *a, const struct ip_set *b)
{
	const struct bitmap_ip *x = a->data;
	const struct bitmap_ip *y = b->data;

	return x->first_ip == y->first_ip &&
	       x->last_ip == y->last_ip &&
	       x->netmask == y->netmask &&
	       x->timeout == y->timeout;
}

static const struct ip_set_type_variant bitmap_ip = {
	.kadt	= bitmap_ip_kadt,
	.uadt	= bitmap_ip_uadt,
	.adt	= {
		[IPSET_ADD] = bitmap_ip_add,
		[IPSET_DEL] = bitmap_ip_del,
		[IPSET_TEST] = bitmap_ip_test,
	},
	.destroy = bitmap_ip_destroy,
	.flush	= bitmap_ip_flush,
	.head	= bitmap_ip_head,
	.list	= bitmap_ip_list,
	.same_set = bitmap_ip_same_set,
};

static const struct ip_set_type_variant bitmap_tip = {
	.kadt	= bitmap_ip_kadt,
	.uadt	= bitmap_ip_uadt,
	.adt	= {
		[IPSET_ADD] = bitmap_ip_tadd,
		[IPSET_DEL] = bitmap_ip_tdel,
		[IPSET_TEST] = bitmap_ip_ttest,
	},
	.destroy = bitmap_ip_destroy,
	.flush	= bitmap_ip_flush,
	.head	= bitmap_ip_head,
	.list	= bitmap_ip_tlist,
	.same_set = bitmap_ip_same_set,
};

static void
bitmap_ip_gc(unsigned long ul_set)
{
	struct ip_set *set = (struct ip_set *) ul_set;
	struct bitmap_ip *map = set->data;
	unsigned long *table = map->members;
	u32 id;

	/* We run parallel with other readers (test element)
	 * but adding/deleting new entries is locked out */
	read_lock_bh(&set->lock);
	for (id = 0; id < map->elements; id++)
		if (ip_set_timeout_expired(table[id]))
			table[id] = IPSET_ELEM_UNSET;
	read_unlock_bh(&set->lock);

	map->gc.expires = jiffies + IPSET_GC_PERIOD(map->timeout) * HZ;
	add_timer(&map->gc);
}

static void
bitmap_ip_gc_init(struct ip_set *set)
{
	struct bitmap_ip *map = set->data;

	init_timer(&map->gc);
	map->gc.data = (unsigned long) set;
	map->gc.function = bitmap_ip_gc;
	map->gc.expires = jiffies + IPSET_GC_PERIOD(map->timeout) * HZ;
	add_timer(&map->gc);
}

/* Create bitmap:ip type of sets */

static bool
init_map_ip(struct ip_set *set, struct bitmap_ip *map,
	    u32 first_ip, u32 last_ip,
	    u32 elements, u32 hosts, u8 netmask)
{
	map->members = ip_set_alloc(map->memsize);
	if (!map->members)
		return false;
	map->first_ip = first_ip;
	map->last_ip = last_ip;
	map->elements = elements;
	map->hosts = hosts;
	map->netmask = netmask;
	map->timeout = IPSET_NO_TIMEOUT;

	set->data = map;
	set->family = AF_INET;

	return true;
}

static int
bitmap_ip_create(struct ip_set *set, struct nlattr *tb[], u32 flags)
{
	struct bitmap_ip *map;
	u32 first_ip, last_ip, hosts, elements;
	u8 netmask = 32;
	int ret;

	if (unlikely(!tb[IPSET_ATTR_IP] ||
		     !ip_set_optattr_netorder(tb, IPSET_ATTR_TIMEOUT)))
		return -IPSET_ERR_PROTOCOL;

	ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP], &first_ip);
	if (ret)
		return ret;

	if (tb[IPSET_ATTR_IP_TO]) {
		ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP_TO], &last_ip);
		if (ret)
			return ret;
		if (first_ip > last_ip) {
			u32 tmp = first_ip;

			first_ip = last_ip;
			last_ip = tmp;
		}
	} else if (tb[IPSET_ATTR_CIDR]) {
		u8 cidr = nla_get_u8(tb[IPSET_ATTR_CIDR]);

		if (cidr >= 32)
			return -IPSET_ERR_INVALID_CIDR;
		last_ip = first_ip | ~ip_set_hostmask(cidr);
	} else
		return -IPSET_ERR_PROTOCOL;

	if (tb[IPSET_ATTR_NETMASK]) {
		netmask = nla_get_u8(tb[IPSET_ATTR_NETMASK]);

		if (netmask > 32)
			return -IPSET_ERR_INVALID_NETMASK;

		first_ip &= ip_set_hostmask(netmask);
		last_ip |= ~ip_set_hostmask(netmask);
	}

	if (netmask == 32) {
		hosts = 1;
		elements = last_ip - first_ip + 1;
	} else {
		u8 mask_bits;
		u32 mask;

		mask = range_to_mask(first_ip, last_ip, &mask_bits);

		if ((!mask && (first_ip || last_ip != 0xFFFFFFFF)) ||
		    netmask <= mask_bits)
			return -IPSET_ERR_BITMAP_RANGE;

		pr_debug("mask_bits %u, netmask %u\n", mask_bits, netmask);
		hosts = 2 << (32 - netmask - 1);
		elements = 2 << (netmask - mask_bits - 1);
	}
	if (elements > IPSET_BITMAP_MAX_RANGE + 1)
		return -IPSET_ERR_BITMAP_RANGE_SIZE;

	pr_debug("hosts %u, elements %u\n", hosts, elements);

	map = kzalloc(sizeof(*map), GFP_KERNEL);
	if (!map)
		return -ENOMEM;

	if (tb[IPSET_ATTR_TIMEOUT]) {
		map->memsize = elements * sizeof(unsigned long);

		if (!init_map_ip(set, map, first_ip, last_ip,
				 elements, hosts, netmask)) {
			kfree(map);
			return -ENOMEM;
		}

		map->timeout = ip_set_timeout_uget(tb[IPSET_ATTR_TIMEOUT]);
		set->variant = &bitmap_tip;

		bitmap_ip_gc_init(set);
	} else {
		map->memsize = bitmap_bytes(0, elements - 1);

		if (!init_map_ip(set, map, first_ip, last_ip,
				 elements, hosts, netmask)) {
			kfree(map);
			return -ENOMEM;
		}

		set->variant = &bitmap_ip;
	}
	return 0;
}

static struct ip_set_type bitmap_ip_type __read_mostly = {
	.name		= "bitmap:ip",
	.protocol	= IPSET_PROTOCOL,
	.features	= IPSET_TYPE_IP,
	.dimension	= IPSET_DIM_ONE,
	.family		= AF_INET,
	.revision	= 0,
	.create		= bitmap_ip_create,
	.create_policy	= {
		[IPSET_ATTR_IP]		= { .type = NLA_NESTED },
		[IPSET_ATTR_IP_TO]	= { .type = NLA_NESTED },
		[IPSET_ATTR_CIDR]	= { .type = NLA_U8 },
		[IPSET_ATTR_NETMASK]	= { .type = NLA_U8  },
		[IPSET_ATTR_TIMEOUT]	= { .type = NLA_U32 },
	},
	.adt_policy	= {
		[IPSET_ATTR_IP]		= { .type = NLA_NESTED },
		[IPSET_ATTR_IP_TO]	= { .type = NLA_NESTED },
		[IPSET_ATTR_CIDR]	= { .type = NLA_U8 },
		[IPSET_ATTR_TIMEOUT]	= { .type = NLA_U32 },
		[IPSET_ATTR_LINENO]	= { .type = NLA_U32 },
	},
	.me		= THIS_MODULE,
};

static int __init
bitmap_ip_init(void)
{
	return ip_set_type_register(&bitmap_ip_type);
}

static void __exit
bitmap_ip_fini(void)
{
	ip_set_type_unregister(&bitmap_ip_type);
}

module_init(bitmap_ip_init);
module_exit(bitmap_ip_fini);