1// SPDX-License-Identifier: GPL-2.0-only
2/* Copyright (C) 2003-2013 Jozsef Kadlecsik <kadlec@netfilter.org> */
3
4/* Kernel module implementing an IP set type: the hash:net type */
5
6#include <linux/jhash.h>
7#include <linux/module.h>
8#include <linux/ip.h>
9#include <linux/skbuff.h>
10#include <linux/errno.h>
11#include <linux/random.h>
12#include <net/ip.h>
13#include <net/ipv6.h>
14#include <net/netlink.h>
15
16#include <linux/netfilter.h>
17#include <linux/netfilter/ipset/pfxlen.h>
18#include <linux/netfilter/ipset/ip_set.h>
19#include <linux/netfilter/ipset/ip_set_hash.h>
20
21#define IPSET_TYPE_REV_MIN	0
22/*				1    Range as input support for IPv4 added */
23/*				2    nomatch flag support added */
24/*				3    Counters support added */
25/*				4    Comments support added */
26/*				5    Forceadd support added */
27/*				6    skbinfo support added */
28#define IPSET_TYPE_REV_MAX	7 /* bucketsize, initval support added */
29
30MODULE_LICENSE("GPL");
31MODULE_AUTHOR("Jozsef Kadlecsik <kadlec@netfilter.org>");
32IP_SET_MODULE_DESC("hash:net", IPSET_TYPE_REV_MIN, IPSET_TYPE_REV_MAX);
33MODULE_ALIAS("ip_set_hash:net");
34
35/* Type specific function prefix */
36#define HTYPE		hash_net
37#define IP_SET_HASH_WITH_NETS
38
39/* IPv4 variant */
40
41/* Member elements  */
42struct hash_net4_elem {
43	__be32 ip;
44	u16 padding0;
45	u8 nomatch;
46	u8 cidr;
47};
48
49/* Common functions */
50
51static bool
52hash_net4_data_equal(const struct hash_net4_elem *ip1,
53		     const struct hash_net4_elem *ip2,
54		     u32 *multi)
55{
56	return ip1->ip == ip2->ip &&
57	       ip1->cidr == ip2->cidr;
58}
59
60static int
61hash_net4_do_data_match(const struct hash_net4_elem *elem)
62{
63	return elem->nomatch ? -ENOTEMPTY : 1;
64}
65
66static void
67hash_net4_data_set_flags(struct hash_net4_elem *elem, u32 flags)
68{
69	elem->nomatch = (flags >> 16) & IPSET_FLAG_NOMATCH;
70}
71
72static void
73hash_net4_data_reset_flags(struct hash_net4_elem *elem, u8 *flags)
74{
75	swap(*flags, elem->nomatch);
76}
77
78static void
79hash_net4_data_netmask(struct hash_net4_elem *elem, u8 cidr)
80{
81	elem->ip &= ip_set_netmask(cidr);
82	elem->cidr = cidr;
83}
84
85static bool
86hash_net4_data_list(struct sk_buff *skb, const struct hash_net4_elem *data)
87{
88	u32 flags = data->nomatch ? IPSET_FLAG_NOMATCH : 0;
89
90	if (nla_put_ipaddr4(skb, IPSET_ATTR_IP, data->ip) ||
91	    nla_put_u8(skb, IPSET_ATTR_CIDR, data->cidr) ||
92	    (flags &&
93	     nla_put_net32(skb, IPSET_ATTR_CADT_FLAGS, htonl(flags))))
94		goto nla_put_failure;
95	return false;
96
97nla_put_failure:
98	return true;
99}
100
101static void
102hash_net4_data_next(struct hash_net4_elem *next,
103		    const struct hash_net4_elem *d)
104{
105	next->ip = d->ip;
106}
107
108#define MTYPE		hash_net4
109#define HOST_MASK	32
110#include "ip_set_hash_gen.h"
111
112static int
113hash_net4_kadt(struct ip_set *set, const struct sk_buff *skb,
114	       const struct xt_action_param *par,
115	       enum ipset_adt adt, struct ip_set_adt_opt *opt)
116{
117	const struct hash_net4 *h = set->data;
118	ipset_adtfn adtfn = set->variant->adt[adt];
119	struct hash_net4_elem e = {
120		.cidr = INIT_CIDR(h->nets[0].cidr[0], HOST_MASK),
121	};
122	struct ip_set_ext ext = IP_SET_INIT_KEXT(skb, opt, set);
123
124	if (e.cidr == 0)
125		return -EINVAL;
126	if (adt == IPSET_TEST)
127		e.cidr = HOST_MASK;
128
129	ip4addrptr(skb, opt->flags & IPSET_DIM_ONE_SRC, &e.ip);
130	e.ip &= ip_set_netmask(e.cidr);
131
132	return adtfn(set, &e, &ext, &opt->ext, opt->cmdflags);
133}
134
135static int
136hash_net4_uadt(struct ip_set *set, struct nlattr *tb[],
137	       enum ipset_adt adt, u32 *lineno, u32 flags, bool retried)
138{
139	struct hash_net4 *h = set->data;
140	ipset_adtfn adtfn = set->variant->adt[adt];
141	struct hash_net4_elem e = { .cidr = HOST_MASK };
142	struct ip_set_ext ext = IP_SET_INIT_UEXT(set);
143	u32 ip = 0, ip_to = 0, i = 0;
144	int ret;
145
146	if (tb[IPSET_ATTR_LINENO])
147		*lineno = nla_get_u32(tb[IPSET_ATTR_LINENO]);
148
149	if (unlikely(!tb[IPSET_ATTR_IP] ||
150		     !ip_set_optattr_netorder(tb, IPSET_ATTR_CADT_FLAGS)))
151		return -IPSET_ERR_PROTOCOL;
152
153	ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP], &ip);
154	if (ret)
155		return ret;
156
157	ret = ip_set_get_extensions(set, tb, &ext);
158	if (ret)
159		return ret;
160
161	if (tb[IPSET_ATTR_CIDR]) {
162		e.cidr = nla_get_u8(tb[IPSET_ATTR_CIDR]);
163		if (!e.cidr || e.cidr > HOST_MASK)
164			return -IPSET_ERR_INVALID_CIDR;
165	}
166
167	if (tb[IPSET_ATTR_CADT_FLAGS]) {
168		u32 cadt_flags = ip_set_get_h32(tb[IPSET_ATTR_CADT_FLAGS]);
169
170		if (cadt_flags & IPSET_FLAG_NOMATCH)
171			flags |= (IPSET_FLAG_NOMATCH << 16);
172	}
173
174	if (adt == IPSET_TEST || !tb[IPSET_ATTR_IP_TO]) {
175		e.ip = htonl(ip & ip_set_hostmask(e.cidr));
176		ret = adtfn(set, &e, &ext, &ext, flags);
177		return ip_set_enomatch(ret, flags, adt, set) ? -ret :
178		       ip_set_eexist(ret, flags) ? 0 : ret;
179	}
180
181	ip_to = ip;
182	if (tb[IPSET_ATTR_IP_TO]) {
183		ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP_TO], &ip_to);
184		if (ret)
185			return ret;
186		if (ip_to < ip)
187			swap(ip, ip_to);
188		if (ip + UINT_MAX == ip_to)
189			return -IPSET_ERR_HASH_RANGE;
190	}
191
192	if (retried)
193		ip = ntohl(h->next.ip);
194	do {
195		i++;
196		e.ip = htonl(ip);
197		if (i > IPSET_MAX_RANGE) {
198			hash_net4_data_next(&h->next, &e);
199			return -ERANGE;
200		}
201		ip = ip_set_range_to_cidr(ip, ip_to, &e.cidr);
202		ret = adtfn(set, &e, &ext, &ext, flags);
203		if (ret && !ip_set_eexist(ret, flags))
204			return ret;
205
206		ret = 0;
207	} while (ip++ < ip_to);
208	return ret;
209}
210
211/* IPv6 variant */
212
213struct hash_net6_elem {
214	union nf_inet_addr ip;
215	u16 padding0;
216	u8 nomatch;
217	u8 cidr;
218};
219
220/* Common functions */
221
222static bool
223hash_net6_data_equal(const struct hash_net6_elem *ip1,
224		     const struct hash_net6_elem *ip2,
225		     u32 *multi)
226{
227	return ipv6_addr_equal(&ip1->ip.in6, &ip2->ip.in6) &&
228	       ip1->cidr == ip2->cidr;
229}
230
231static int
232hash_net6_do_data_match(const struct hash_net6_elem *elem)
233{
234	return elem->nomatch ? -ENOTEMPTY : 1;
235}
236
237static void
238hash_net6_data_set_flags(struct hash_net6_elem *elem, u32 flags)
239{
240	elem->nomatch = (flags >> 16) & IPSET_FLAG_NOMATCH;
241}
242
243static void
244hash_net6_data_reset_flags(struct hash_net6_elem *elem, u8 *flags)
245{
246	swap(*flags, elem->nomatch);
247}
248
249static void
250hash_net6_data_netmask(struct hash_net6_elem *elem, u8 cidr)
251{
252	ip6_netmask(&elem->ip, cidr);
253	elem->cidr = cidr;
254}
255
256static bool
257hash_net6_data_list(struct sk_buff *skb, const struct hash_net6_elem *data)
258{
259	u32 flags = data->nomatch ? IPSET_FLAG_NOMATCH : 0;
260
261	if (nla_put_ipaddr6(skb, IPSET_ATTR_IP, &data->ip.in6) ||
262	    nla_put_u8(skb, IPSET_ATTR_CIDR, data->cidr) ||
263	    (flags &&
264	     nla_put_net32(skb, IPSET_ATTR_CADT_FLAGS, htonl(flags))))
265		goto nla_put_failure;
266	return false;
267
268nla_put_failure:
269	return true;
270}
271
272static void
273hash_net6_data_next(struct hash_net6_elem *next,
274		    const struct hash_net6_elem *d)
275{
276}
277
278#undef MTYPE
279#undef HOST_MASK
280
281#define MTYPE		hash_net6
282#define HOST_MASK	128
283#define IP_SET_EMIT_CREATE
284#include "ip_set_hash_gen.h"
285
286static int
287hash_net6_kadt(struct ip_set *set, const struct sk_buff *skb,
288	       const struct xt_action_param *par,
289	       enum ipset_adt adt, struct ip_set_adt_opt *opt)
290{
291	const struct hash_net6 *h = set->data;
292	ipset_adtfn adtfn = set->variant->adt[adt];
293	struct hash_net6_elem e = {
294		.cidr = INIT_CIDR(h->nets[0].cidr[0], HOST_MASK),
295	};
296	struct ip_set_ext ext = IP_SET_INIT_KEXT(skb, opt, set);
297
298	if (e.cidr == 0)
299		return -EINVAL;
300	if (adt == IPSET_TEST)
301		e.cidr = HOST_MASK;
302
303	ip6addrptr(skb, opt->flags & IPSET_DIM_ONE_SRC, &e.ip.in6);
304	ip6_netmask(&e.ip, e.cidr);
305
306	return adtfn(set, &e, &ext, &opt->ext, opt->cmdflags);
307}
308
309static int
310hash_net6_uadt(struct ip_set *set, struct nlattr *tb[],
311	       enum ipset_adt adt, u32 *lineno, u32 flags, bool retried)
312{
313	ipset_adtfn adtfn = set->variant->adt[adt];
314	struct hash_net6_elem e = { .cidr = HOST_MASK };
315	struct ip_set_ext ext = IP_SET_INIT_UEXT(set);
316	int ret;
317
318	if (tb[IPSET_ATTR_LINENO])
319		*lineno = nla_get_u32(tb[IPSET_ATTR_LINENO]);
320
321	if (unlikely(!tb[IPSET_ATTR_IP] ||
322		     !ip_set_optattr_netorder(tb, IPSET_ATTR_CADT_FLAGS)))
323		return -IPSET_ERR_PROTOCOL;
324	if (unlikely(tb[IPSET_ATTR_IP_TO]))
325		return -IPSET_ERR_HASH_RANGE_UNSUPPORTED;
326
327	ret = ip_set_get_ipaddr6(tb[IPSET_ATTR_IP], &e.ip);
328	if (ret)
329		return ret;
330
331	ret = ip_set_get_extensions(set, tb, &ext);
332	if (ret)
333		return ret;
334
335	if (tb[IPSET_ATTR_CIDR]) {
336		e.cidr = nla_get_u8(tb[IPSET_ATTR_CIDR]);
337		if (!e.cidr || e.cidr > HOST_MASK)
338			return -IPSET_ERR_INVALID_CIDR;
339	}
340
341	ip6_netmask(&e.ip, e.cidr);
342
343	if (tb[IPSET_ATTR_CADT_FLAGS]) {
344		u32 cadt_flags = ip_set_get_h32(tb[IPSET_ATTR_CADT_FLAGS]);
345
346		if (cadt_flags & IPSET_FLAG_NOMATCH)
347			flags |= (IPSET_FLAG_NOMATCH << 16);
348	}
349
350	ret = adtfn(set, &e, &ext, &ext, flags);
351
352	return ip_set_enomatch(ret, flags, adt, set) ? -ret :
353	       ip_set_eexist(ret, flags) ? 0 : ret;
354}
355
356static struct ip_set_type hash_net_type __read_mostly = {
357	.name		= "hash:net",
358	.protocol	= IPSET_PROTOCOL,
359	.features	= IPSET_TYPE_IP | IPSET_TYPE_NOMATCH,
360	.dimension	= IPSET_DIM_ONE,
361	.family		= NFPROTO_UNSPEC,
362	.revision_min	= IPSET_TYPE_REV_MIN,
363	.revision_max	= IPSET_TYPE_REV_MAX,
364	.create_flags[IPSET_TYPE_REV_MAX] = IPSET_CREATE_FLAG_BUCKETSIZE,
365	.create		= hash_net_create,
366	.create_policy	= {
367		[IPSET_ATTR_HASHSIZE]	= { .type = NLA_U32 },
368		[IPSET_ATTR_MAXELEM]	= { .type = NLA_U32 },
369		[IPSET_ATTR_INITVAL]	= { .type = NLA_U32 },
370		[IPSET_ATTR_BUCKETSIZE]	= { .type = NLA_U8 },
371		[IPSET_ATTR_RESIZE]	= { .type = NLA_U8  },
372		[IPSET_ATTR_TIMEOUT]	= { .type = NLA_U32 },
373		[IPSET_ATTR_CADT_FLAGS]	= { .type = NLA_U32 },
374	},
375	.adt_policy	= {
376		[IPSET_ATTR_IP]		= { .type = NLA_NESTED },
377		[IPSET_ATTR_IP_TO]	= { .type = NLA_NESTED },
378		[IPSET_ATTR_CIDR]	= { .type = NLA_U8 },
379		[IPSET_ATTR_TIMEOUT]	= { .type = NLA_U32 },
380		[IPSET_ATTR_LINENO]	= { .type = NLA_U32 },
381		[IPSET_ATTR_CADT_FLAGS]	= { .type = NLA_U32 },
382		[IPSET_ATTR_BYTES]	= { .type = NLA_U64 },
383		[IPSET_ATTR_PACKETS]	= { .type = NLA_U64 },
384		[IPSET_ATTR_COMMENT]	= { .type = NLA_NUL_STRING,
385					    .len  = IPSET_MAX_COMMENT_SIZE },
386		[IPSET_ATTR_SKBMARK]	= { .type = NLA_U64 },
387		[IPSET_ATTR_SKBPRIO]	= { .type = NLA_U32 },
388		[IPSET_ATTR_SKBQUEUE]	= { .type = NLA_U16 },
389	},
390	.me		= THIS_MODULE,
391};
392
393static int __init
394hash_net_init(void)
395{
396	return ip_set_type_register(&hash_net_type);
397}
398
399static void __exit
400hash_net_fini(void)
401{
402	rcu_barrier();
403	ip_set_type_unregister(&hash_net_type);
404}
405
406module_init(hash_net_init);
407module_exit(hash_net_fini);
408