xref: /linux/net/netfilter/ipset/ip_set_hash_net.c (revision e5a52fd2b8cdb700b3c07b030e050a49ef3156b9) 
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 #define IPSET_TYPE_REV_MAX	6 /* skbinfo mapping support added */
28 
29 MODULE_LICENSE("GPL");
30 MODULE_AUTHOR("Jozsef Kadlecsik <kadlec@netfilter.org>");
31 IP_SET_MODULE_DESC("hash:net", IPSET_TYPE_REV_MIN, IPSET_TYPE_REV_MAX);
32 MODULE_ALIAS("ip_set_hash:net");
33 
34 /* Type specific function prefix */
35 #define HTYPE		hash_net
36 #define IP_SET_HASH_WITH_NETS
37 
38 /* IPv4 variant */
39 
40 /* Member elements  */
41 struct hash_net4_elem {
42 	__be32 ip;
43 	u16 padding0;
44 	u8 nomatch;
45 	u8 cidr;
46 };
47 
48 /* Common functions */
49 
50 static bool
51 hash_net4_data_equal(const struct hash_net4_elem *ip1,
52 		     const struct hash_net4_elem *ip2,
53 		     u32 *multi)
54 {
55 	return ip1->ip == ip2->ip &&
56 	       ip1->cidr == ip2->cidr;
57 }
58 
59 static int
60 hash_net4_do_data_match(const struct hash_net4_elem *elem)
61 {
62 	return elem->nomatch ? -ENOTEMPTY : 1;
63 }
64 
65 static void
66 hash_net4_data_set_flags(struct hash_net4_elem *elem, u32 flags)
67 {
68 	elem->nomatch = (flags >> 16) & IPSET_FLAG_NOMATCH;
69 }
70 
71 static void
72 hash_net4_data_reset_flags(struct hash_net4_elem *elem, u8 *flags)
73 {
74 	swap(*flags, elem->nomatch);
75 }
76 
77 static void
78 hash_net4_data_netmask(struct hash_net4_elem *elem, u8 cidr)
79 {
80 	elem->ip &= ip_set_netmask(cidr);
81 	elem->cidr = cidr;
82 }
83 
84 static bool
85 hash_net4_data_list(struct sk_buff *skb, const struct hash_net4_elem *data)
86 {
87 	u32 flags = data->nomatch ? IPSET_FLAG_NOMATCH : 0;
88 
89 	if (nla_put_ipaddr4(skb, IPSET_ATTR_IP, data->ip) ||
90 	    nla_put_u8(skb, IPSET_ATTR_CIDR, data->cidr) ||
91 	    (flags &&
92 	     nla_put_net32(skb, IPSET_ATTR_CADT_FLAGS, htonl(flags))))
93 		goto nla_put_failure;
94 	return false;
95 
96 nla_put_failure:
97 	return true;
98 }
99 
100 static void
101 hash_net4_data_next(struct hash_net4_elem *next,
102 		    const struct hash_net4_elem *d)
103 {
104 	next->ip = d->ip;
105 }
106 
107 #define MTYPE		hash_net4
108 #define HOST_MASK	32
109 #include "ip_set_hash_gen.h"
110 
111 static int
112 hash_net4_kadt(struct ip_set *set, const struct sk_buff *skb,
113 	       const struct xt_action_param *par,
114 	       enum ipset_adt adt, struct ip_set_adt_opt *opt)
115 {
116 	const struct hash_net4 *h = set->data;
117 	ipset_adtfn adtfn = set->variant->adt[adt];
118 	struct hash_net4_elem e = {
119 		.cidr = INIT_CIDR(h->nets[0].cidr[0], HOST_MASK),
120 	};
121 	struct ip_set_ext ext = IP_SET_INIT_KEXT(skb, opt, set);
122 
123 	if (e.cidr == 0)
124 		return -EINVAL;
125 	if (adt == IPSET_TEST)
126 		e.cidr = HOST_MASK;
127 
128 	ip4addrptr(skb, opt->flags & IPSET_DIM_ONE_SRC, &e.ip);
129 	e.ip &= ip_set_netmask(e.cidr);
130 
131 	return adtfn(set, &e, &ext, &opt->ext, opt->cmdflags);
132 }
133 
134 static int
135 hash_net4_uadt(struct ip_set *set, struct nlattr *tb[],
136 	       enum ipset_adt adt, u32 *lineno, u32 flags, bool retried)
137 {
138 	const struct hash_net4 *h = set->data;
139 	ipset_adtfn adtfn = set->variant->adt[adt];
140 	struct hash_net4_elem e = { .cidr = HOST_MASK };
141 	struct ip_set_ext ext = IP_SET_INIT_UEXT(set);
142 	u32 ip = 0, ip_to = 0;
143 	int ret;
144 
145 	if (tb[IPSET_ATTR_LINENO])
146 		*lineno = nla_get_u32(tb[IPSET_ATTR_LINENO]);
147 
148 	if (unlikely(!tb[IPSET_ATTR_IP] ||
149 		     !ip_set_optattr_netorder(tb, IPSET_ATTR_CADT_FLAGS)))
150 		return -IPSET_ERR_PROTOCOL;
151 
152 	ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP], &ip);
153 	if (ret)
154 		return ret;
155 
156 	ret = ip_set_get_extensions(set, tb, &ext);
157 	if (ret)
158 		return ret;
159 
160 	if (tb[IPSET_ATTR_CIDR]) {
161 		e.cidr = nla_get_u8(tb[IPSET_ATTR_CIDR]);
162 		if (!e.cidr || e.cidr > HOST_MASK)
163 			return -IPSET_ERR_INVALID_CIDR;
164 	}
165 
166 	if (tb[IPSET_ATTR_CADT_FLAGS]) {
167 		u32 cadt_flags = ip_set_get_h32(tb[IPSET_ATTR_CADT_FLAGS]);
168 
169 		if (cadt_flags & IPSET_FLAG_NOMATCH)
170 			flags |= (IPSET_FLAG_NOMATCH << 16);
171 	}
172 
173 	if (adt == IPSET_TEST || !tb[IPSET_ATTR_IP_TO]) {
174 		e.ip = htonl(ip & ip_set_hostmask(e.cidr));
175 		ret = adtfn(set, &e, &ext, &ext, flags);
176 		return ip_set_enomatch(ret, flags, adt, set) ? -ret :
177 		       ip_set_eexist(ret, flags) ? 0 : ret;
178 	}
179 
180 	ip_to = ip;
181 	if (tb[IPSET_ATTR_IP_TO]) {
182 		ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP_TO], &ip_to);
183 		if (ret)
184 			return ret;
185 		if (ip_to < ip)
186 			swap(ip, ip_to);
187 		if (ip + UINT_MAX == ip_to)
188 			return -IPSET_ERR_HASH_RANGE;
189 	}
190 	if (retried)
191 		ip = ntohl(h->next.ip);
192 	do {
193 		e.ip = htonl(ip);
194 		ip = ip_set_range_to_cidr(ip, ip_to, &e.cidr);
195 		ret = adtfn(set, &e, &ext, &ext, flags);
196 		if (ret && !ip_set_eexist(ret, flags))
197 			return ret;
198 
199 		ret = 0;
200 	} while (ip++ < ip_to);
201 	return ret;
202 }
203 
204 /* IPv6 variant */
205 
206 struct hash_net6_elem {
207 	union nf_inet_addr ip;
208 	u16 padding0;
209 	u8 nomatch;
210 	u8 cidr;
211 };
212 
213 /* Common functions */
214 
215 static bool
216 hash_net6_data_equal(const struct hash_net6_elem *ip1,
217 		     const struct hash_net6_elem *ip2,
218 		     u32 *multi)
219 {
220 	return ipv6_addr_equal(&ip1->ip.in6, &ip2->ip.in6) &&
221 	       ip1->cidr == ip2->cidr;
222 }
223 
224 static int
225 hash_net6_do_data_match(const struct hash_net6_elem *elem)
226 {
227 	return elem->nomatch ? -ENOTEMPTY : 1;
228 }
229 
230 static void
231 hash_net6_data_set_flags(struct hash_net6_elem *elem, u32 flags)
232 {
233 	elem->nomatch = (flags >> 16) & IPSET_FLAG_NOMATCH;
234 }
235 
236 static void
237 hash_net6_data_reset_flags(struct hash_net6_elem *elem, u8 *flags)
238 {
239 	swap(*flags, elem->nomatch);
240 }
241 
242 static void
243 hash_net6_data_netmask(struct hash_net6_elem *elem, u8 cidr)
244 {
245 	ip6_netmask(&elem->ip, cidr);
246 	elem->cidr = cidr;
247 }
248 
249 static bool
250 hash_net6_data_list(struct sk_buff *skb, const struct hash_net6_elem *data)
251 {
252 	u32 flags = data->nomatch ? IPSET_FLAG_NOMATCH : 0;
253 
254 	if (nla_put_ipaddr6(skb, IPSET_ATTR_IP, &data->ip.in6) ||
255 	    nla_put_u8(skb, IPSET_ATTR_CIDR, data->cidr) ||
256 	    (flags &&
257 	     nla_put_net32(skb, IPSET_ATTR_CADT_FLAGS, htonl(flags))))
258 		goto nla_put_failure;
259 	return false;
260 
261 nla_put_failure:
262 	return true;
263 }
264 
265 static void
266 hash_net6_data_next(struct hash_net6_elem *next,
267 		    const struct hash_net6_elem *d)
268 {
269 }
270 
271 #undef MTYPE
272 #undef HOST_MASK
273 
274 #define MTYPE		hash_net6
275 #define HOST_MASK	128
276 #define IP_SET_EMIT_CREATE
277 #include "ip_set_hash_gen.h"
278 
279 static int
280 hash_net6_kadt(struct ip_set *set, const struct sk_buff *skb,
281 	       const struct xt_action_param *par,
282 	       enum ipset_adt adt, struct ip_set_adt_opt *opt)
283 {
284 	const struct hash_net6 *h = set->data;
285 	ipset_adtfn adtfn = set->variant->adt[adt];
286 	struct hash_net6_elem e = {
287 		.cidr = INIT_CIDR(h->nets[0].cidr[0], HOST_MASK),
288 	};
289 	struct ip_set_ext ext = IP_SET_INIT_KEXT(skb, opt, set);
290 
291 	if (e.cidr == 0)
292 		return -EINVAL;
293 	if (adt == IPSET_TEST)
294 		e.cidr = HOST_MASK;
295 
296 	ip6addrptr(skb, opt->flags & IPSET_DIM_ONE_SRC, &e.ip.in6);
297 	ip6_netmask(&e.ip, e.cidr);
298 
299 	return adtfn(set, &e, &ext, &opt->ext, opt->cmdflags);
300 }
301 
302 static int
303 hash_net6_uadt(struct ip_set *set, struct nlattr *tb[],
304 	       enum ipset_adt adt, u32 *lineno, u32 flags, bool retried)
305 {
306 	ipset_adtfn adtfn = set->variant->adt[adt];
307 	struct hash_net6_elem e = { .cidr = HOST_MASK };
308 	struct ip_set_ext ext = IP_SET_INIT_UEXT(set);
309 	int ret;
310 
311 	if (tb[IPSET_ATTR_LINENO])
312 		*lineno = nla_get_u32(tb[IPSET_ATTR_LINENO]);
313 
314 	if (unlikely(!tb[IPSET_ATTR_IP] ||
315 		     !ip_set_optattr_netorder(tb, IPSET_ATTR_CADT_FLAGS)))
316 		return -IPSET_ERR_PROTOCOL;
317 	if (unlikely(tb[IPSET_ATTR_IP_TO]))
318 		return -IPSET_ERR_HASH_RANGE_UNSUPPORTED;
319 
320 	ret = ip_set_get_ipaddr6(tb[IPSET_ATTR_IP], &e.ip);
321 	if (ret)
322 		return ret;
323 
324 	ret = ip_set_get_extensions(set, tb, &ext);
325 	if (ret)
326 		return ret;
327 
328 	if (tb[IPSET_ATTR_CIDR]) {
329 		e.cidr = nla_get_u8(tb[IPSET_ATTR_CIDR]);
330 		if (!e.cidr || e.cidr > HOST_MASK)
331 			return -IPSET_ERR_INVALID_CIDR;
332 	}
333 
334 	ip6_netmask(&e.ip, e.cidr);
335 
336 	if (tb[IPSET_ATTR_CADT_FLAGS]) {
337 		u32 cadt_flags = ip_set_get_h32(tb[IPSET_ATTR_CADT_FLAGS]);
338 
339 		if (cadt_flags & IPSET_FLAG_NOMATCH)
340 			flags |= (IPSET_FLAG_NOMATCH << 16);
341 	}
342 
343 	ret = adtfn(set, &e, &ext, &ext, flags);
344 
345 	return ip_set_enomatch(ret, flags, adt, set) ? -ret :
346 	       ip_set_eexist(ret, flags) ? 0 : ret;
347 }
348 
349 static struct ip_set_type hash_net_type __read_mostly = {
350 	.name		= "hash:net",
351 	.protocol	= IPSET_PROTOCOL,
352 	.features	= IPSET_TYPE_IP | IPSET_TYPE_NOMATCH,
353 	.dimension	= IPSET_DIM_ONE,
354 	.family		= NFPROTO_UNSPEC,
355 	.revision_min	= IPSET_TYPE_REV_MIN,
356 	.revision_max	= IPSET_TYPE_REV_MAX,
357 	.create		= hash_net_create,
358 	.create_policy	= {
359 		[IPSET_ATTR_HASHSIZE]	= { .type = NLA_U32 },
360 		[IPSET_ATTR_MAXELEM]	= { .type = NLA_U32 },
361 		[IPSET_ATTR_PROBES]	= { .type = NLA_U8 },
362 		[IPSET_ATTR_RESIZE]	= { .type = NLA_U8  },
363 		[IPSET_ATTR_TIMEOUT]	= { .type = NLA_U32 },
364 		[IPSET_ATTR_CADT_FLAGS]	= { .type = NLA_U32 },
365 	},
366 	.adt_policy	= {
367 		[IPSET_ATTR_IP]		= { .type = NLA_NESTED },
368 		[IPSET_ATTR_IP_TO]	= { .type = NLA_NESTED },
369 		[IPSET_ATTR_CIDR]	= { .type = NLA_U8 },
370 		[IPSET_ATTR_TIMEOUT]	= { .type = NLA_U32 },
371 		[IPSET_ATTR_LINENO]	= { .type = NLA_U32 },
372 		[IPSET_ATTR_CADT_FLAGS]	= { .type = NLA_U32 },
373 		[IPSET_ATTR_BYTES]	= { .type = NLA_U64 },
374 		[IPSET_ATTR_PACKETS]	= { .type = NLA_U64 },
375 		[IPSET_ATTR_COMMENT]	= { .type = NLA_NUL_STRING,
376 					    .len  = IPSET_MAX_COMMENT_SIZE },
377 		[IPSET_ATTR_SKBMARK]	= { .type = NLA_U64 },
378 		[IPSET_ATTR_SKBPRIO]	= { .type = NLA_U32 },
379 		[IPSET_ATTR_SKBQUEUE]	= { .type = NLA_U16 },
380 	},
381 	.me		= THIS_MODULE,
382 };
383 
384 static int __init
385 hash_net_init(void)
386 {
387 	return ip_set_type_register(&hash_net_type);
388 }
389 
390 static void __exit
391 hash_net_fini(void)
392 {
393 	rcu_barrier();
394 	ip_set_type_unregister(&hash_net_type);
395 }
396 
397 module_init(hash_net_init);
398 module_exit(hash_net_fini);
399