summaryrefslogtreecommitdiffstats
path: root/kernel/ip_set_hash_ip.c
blob: 7f2c1f3db26cf68d8184e3feceea6ca6a007befb (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
/* 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 hash:ip type */

#include <linux/jhash.h>
#include <linux/module.h>
#include <linux/ip.h>
#include <linux/skbuff.h>
#include <linux/errno.h>
#include <linux/uaccess.h>
#include <linux/bitops.h>
#include <linux/spinlock.h>
#include <linux/random.h>
#include <net/ip.h>
#include <net/ipv6.h>
#include <net/netlink.h>
#include <net/tcp.h>

#include <linux/netfilter.h>
#include <linux/netfilter/ipset/pfxlen.h>
#include <linux/netfilter/ipset/ip_set.h>
#include <linux/netfilter/ipset/ip_set_timeout.h>
#include <linux/netfilter/ipset/ip_set_hash.h>

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

/* Type specific function prefix */
#define TYPE		hash_ip

static bool
hash_ip_same_set(const struct ip_set *a, const struct ip_set *b);

#define hash_ip4_same_set	hash_ip_same_set
#define hash_ip6_same_set	hash_ip_same_set

/* The type variant functions: IPv4 */

/* Member elements without timeout */
struct hash_ip4_elem {
	__be32 ip;
};

/* Member elements with timeout support */
struct hash_ip4_telem {
	__be32 ip;
	unsigned long timeout;
};

static inline bool
hash_ip4_data_equal(const struct hash_ip4_elem *ip1,
		    const struct hash_ip4_elem *ip2)
{
	return ip1->ip == ip2->ip;
}

static inline bool
hash_ip4_data_isnull(const struct hash_ip4_elem *elem)
{
	return elem->ip == 0;
}

static inline void
hash_ip4_data_copy(struct hash_ip4_elem *dst, const struct hash_ip4_elem *src)
{
	dst->ip = src->ip;
}

/* Zero valued IP addresses cannot be stored */
static inline void
hash_ip4_data_zero_out(struct hash_ip4_elem *elem)
{
	elem->ip = 0;
}

static inline bool
hash_ip4_data_list(struct sk_buff *skb, const struct hash_ip4_elem *data)
{
	NLA_PUT_IPADDR4(skb, IPSET_ATTR_IP, data->ip);
	return 0;

nla_put_failure:
	return 1;
}

static bool
hash_ip4_data_tlist(struct sk_buff *skb, const struct hash_ip4_elem *data)
{
	const struct hash_ip4_telem *tdata =
		(const struct hash_ip4_telem *)data;

	NLA_PUT_IPADDR4(skb, IPSET_ATTR_IP, tdata->ip);
	NLA_PUT_NET32(skb, IPSET_ATTR_TIMEOUT,
		      htonl(ip_set_timeout_get(tdata->timeout)));

	return 0;

nla_put_failure:
	return 1;
}

#define IP_SET_HASH_WITH_NETMASK
#define PF		4
#define HOST_MASK	32
#include <linux/netfilter/ipset/ip_set_ahash.h>

static int
hash_ip4_kadt(struct ip_set *set, const struct sk_buff *skb,
	      enum ipset_adt adt, u8 pf, u8 dim, u8 flags)
{
	const struct ip_set_hash *h = set->data;
	ipset_adtfn adtfn = set->variant->adt[adt];
	__be32 ip;

	ip4addrptr(skb, flags & IPSET_DIM_ONE_SRC, &ip);
	ip &= ip_set_netmask(h->netmask);
	if (ip == 0)
		return -EINVAL;

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

static const struct nla_policy hash_ip4_adt_policy[IPSET_ATTR_ADT_MAX + 1] = {
	[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 },
};

static int
hash_ip4_uadt(struct ip_set *set, struct nlattr *head, int len,
	      enum ipset_adt adt, u32 *lineno, u32 flags)
{
	const struct ip_set_hash *h = set->data;
	struct nlattr *tb[IPSET_ATTR_ADT_MAX+1];
	ipset_adtfn adtfn = set->variant->adt[adt];
	u32 ip, ip_to, hosts, timeout = h->timeout;
	__be32 nip;
	int ret = 0;

	if (nla_parse(tb, IPSET_ATTR_ADT_MAX, head, len,
		      hash_ip4_adt_policy))
		return -IPSET_ERR_PROTOCOL;

	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;

	ip &= ip_set_hostmask(h->netmask);

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

	if (adt == IPSET_TEST) {
		nip = htonl(ip);
		if (nip == 0)
			return -IPSET_ERR_HASH_ELEM;
		return adtfn(set, &nip, 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);
	} 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;

	hosts = h->netmask == 32 ? 1 : 2 << (32 - h->netmask - 1);

	for (; !before(ip_to, ip); ip += hosts) {
		nip = htonl(ip);
		if (nip == 0)
			return -IPSET_ERR_HASH_ELEM;
		ret = adtfn(set, &nip, timeout);

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

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

	/* Resizing changes htable_bits, so we ignore it */
	return x->maxelem == y->maxelem &&
	       x->timeout == y->timeout &&
	       x->netmask == y->netmask;
}

/* The type variant functions: IPv6 */

struct hash_ip6_elem {
	union nf_inet_addr ip;
};

struct hash_ip6_telem {
	union nf_inet_addr ip;
	unsigned long timeout;
};

static inline bool
hash_ip6_data_equal(const struct hash_ip6_elem *ip1,
		    const struct hash_ip6_elem *ip2)
{
	return ipv6_addr_cmp(&ip1->ip.in6, &ip2->ip.in6) == 0;
}

static inline bool
hash_ip6_data_isnull(const struct hash_ip6_elem *elem)
{
	return ipv6_addr_any(&elem->ip.in6);
}

static inline void
hash_ip6_data_copy(struct hash_ip6_elem *dst, const struct hash_ip6_elem *src)
{
	ipv6_addr_copy(&dst->ip.in6, &src->ip.in6);
}

static inline void
hash_ip6_data_zero_out(struct hash_ip6_elem *elem)
{
	ipv6_addr_set(&elem->ip.in6, 0, 0, 0, 0);
}

static inline void
ip6_netmask(union nf_inet_addr *ip, u8 prefix)
{
	ip->ip6[0] &= ip_set_netmask6(prefix)[0];
	ip->ip6[1] &= ip_set_netmask6(prefix)[1];
	ip->ip6[2] &= ip_set_netmask6(prefix)[2];
	ip->ip6[3] &= ip_set_netmask6(prefix)[3];
}

static bool
hash_ip6_data_list(struct sk_buff *skb, const struct hash_ip6_elem *data)
{
	NLA_PUT_IPADDR6(skb, IPSET_ATTR_IP, &data->ip);
	return 0;

nla_put_failure:
	return 1;
}

static bool
hash_ip6_data_tlist(struct sk_buff *skb, const struct hash_ip6_elem *data)
{
	const struct hash_ip6_telem *e =
		(const struct hash_ip6_telem *)data;

	NLA_PUT_IPADDR6(skb, IPSET_ATTR_IP, &e->ip);
	NLA_PUT_NET32(skb, IPSET_ATTR_TIMEOUT,
		      htonl(ip_set_timeout_get(e->timeout)));
	return 0;

nla_put_failure:
	return 1;
}

#undef PF
#undef HOST_MASK

#define PF		6
#define HOST_MASK	128
#include <linux/netfilter/ipset/ip_set_ahash.h>

static int
hash_ip6_kadt(struct ip_set *set, const struct sk_buff *skb,
	      enum ipset_adt adt, u8 pf, u8 dim, u8 flags)
{
	const struct ip_set_hash *h = set->data;
	ipset_adtfn adtfn = set->variant->adt[adt];
	union nf_inet_addr ip;

	ip6addrptr(skb, flags & IPSET_DIM_ONE_SRC, &ip.in6);
	ip6_netmask(&ip, h->netmask);
	if (ipv6_addr_any(&ip.in6))
		return -EINVAL;

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

static const struct nla_policy hash_ip6_adt_policy[IPSET_ATTR_ADT_MAX + 1] = {
	[IPSET_ATTR_IP]		= { .type = NLA_NESTED },
	[IPSET_ATTR_TIMEOUT]	= { .type = NLA_U32 },
	[IPSET_ATTR_LINENO]	= { .type = NLA_U32 },
};

static int
hash_ip6_uadt(struct ip_set *set, struct nlattr *head, int len,
	      enum ipset_adt adt, u32 *lineno, u32 flags)
{
	const struct ip_set_hash *h = set->data;
	struct nlattr *tb[IPSET_ATTR_ADT_MAX+1];
	ipset_adtfn adtfn = set->variant->adt[adt];
	union nf_inet_addr ip;
	u32 timeout = h->timeout;
	int ret;

	if (nla_parse(tb, IPSET_ATTR_ADT_MAX, head, len,
		      hash_ip6_adt_policy))
		return -IPSET_ERR_PROTOCOL;

	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_ipaddr6(tb[IPSET_ATTR_IP], &ip);
	if (ret)
		return ret;

	ip6_netmask(&ip, h->netmask);
	if (ipv6_addr_any(&ip.in6))
		return -IPSET_ERR_HASH_ELEM;

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

	ret = adtfn(set, &ip, timeout);

	return ip_set_eexist(ret, flags) ? 0 : ret;
}

/* Create hash:ip type of sets */

static const struct nla_policy
hash_ip_create_policy[IPSET_ATTR_CREATE_MAX+1] = {
	[IPSET_ATTR_HASHSIZE]	= { .type = NLA_U32 },
	[IPSET_ATTR_MAXELEM]	= { .type = NLA_U32 },
	[IPSET_ATTR_PROBES]	= { .type = NLA_U8 },
	[IPSET_ATTR_RESIZE]	= { .type = NLA_U8  },
	[IPSET_ATTR_TIMEOUT]	= { .type = NLA_U32 },
	[IPSET_ATTR_NETMASK]	= { .type = NLA_U8  },
};

static int
hash_ip_create(struct ip_set *set, struct nlattr *head, int len, u32 flags)
{
	struct nlattr *tb[IPSET_ATTR_CREATE_MAX+1];
	u32 hashsize = IPSET_DEFAULT_HASHSIZE, maxelem = IPSET_DEFAULT_MAXELEM;
	u8 netmask, hbits;
	struct ip_set_hash *h;

	if (!(set->family == AF_INET || set->family == AF_INET6))
		return -IPSET_ERR_INVALID_FAMILY;
	netmask = set->family == AF_INET ? 32 : 128;
	pr_debug("Create set %s with family %s\n",
		 set->name, set->family == AF_INET ? "inet" : "inet6");

	if (nla_parse(tb, IPSET_ATTR_CREATE_MAX, head, len,
		      hash_ip_create_policy))
		return -IPSET_ERR_PROTOCOL;

	if (unlikely(!ip_set_optattr_netorder(tb, IPSET_ATTR_HASHSIZE) ||
		     !ip_set_optattr_netorder(tb, IPSET_ATTR_MAXELEM) ||
		     !ip_set_optattr_netorder(tb, IPSET_ATTR_TIMEOUT)))
		return -IPSET_ERR_PROTOCOL;

	if (tb[IPSET_ATTR_HASHSIZE]) {
		hashsize = ip_set_get_h32(tb[IPSET_ATTR_HASHSIZE]);
		if (hashsize < IPSET_MIMINAL_HASHSIZE)
			hashsize = IPSET_MIMINAL_HASHSIZE;
	}

	if (tb[IPSET_ATTR_MAXELEM])
		maxelem = ip_set_get_h32(tb[IPSET_ATTR_MAXELEM]);

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

		if ((set->family == AF_INET && netmask > 32) ||
		    (set->family == AF_INET6 && netmask > 128) ||
		    netmask == 0)
			return -IPSET_ERR_INVALID_NETMASK;
	}

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

	h->maxelem = maxelem;
	h->netmask = netmask;
	get_random_bytes(&h->initval, sizeof(h->initval));
	h->timeout = IPSET_NO_TIMEOUT;

	hbits = htable_bits(hashsize);
	h->table = ip_set_alloc(
			sizeof(struct htable)
			+ jhash_size(hbits) * sizeof(struct hbucket),
			GFP_KERNEL);
	if (!h->table) {
		kfree(h);
		return -ENOMEM;
	}
	h->table->htable_bits = hbits;

	set->data = h;

	if (tb[IPSET_ATTR_TIMEOUT]) {
		h->timeout = ip_set_timeout_uget(tb[IPSET_ATTR_TIMEOUT]);

		set->variant = set->family == AF_INET
			? &hash_ip4_tvariant : &hash_ip6_tvariant;

		if (set->family == AF_INET)
			hash_ip4_gc_init(set);
		else
			hash_ip6_gc_init(set);
	} else {
		set->variant = set->family == AF_INET
			? &hash_ip4_variant : &hash_ip6_variant;
	}

	pr_debug("create %s hashsize %u (%u) maxelem %u: %p(%p)\n",
		 set->name, jhash_size(h->table->htable_bits),
		 h->table->htable_bits, h->maxelem, set->data, h->table);

	return 0;
}

static struct ip_set_type hash_ip_type __read_mostly = {
	.name		= "hash:ip",
	.protocol	= IPSET_PROTOCOL,
	.features	= IPSET_TYPE_IP,
	.dimension	= IPSET_DIM_ONE,
	.family		= AF_UNSPEC,
	.revision	= 0,
	.create		= hash_ip_create,
	.me		= THIS_MODULE,
};

static int __init
hash_ip_init(void)
{
	return ip_set_type_register(&hash_ip_type);
}

static void __exit
hash_ip_fini(void)
{
	ip_set_type_unregister(&hash_ip_type);
}

module_init(hash_ip_init);
module_exit(hash_ip_fini);