xref: /linux/net/netfilter/ipset/ip_set_hash_ip.c (revision b83deaa741558babf4b8d51d34f6637ccfff1b26)
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:ip 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 #include <net/tcp.h>
16 
17 #include <linux/netfilter.h>
18 #include <linux/netfilter/ipset/pfxlen.h>
19 #include <linux/netfilter/ipset/ip_set.h>
20 #include <linux/netfilter/ipset/ip_set_hash.h>
21 
22 #define IPSET_TYPE_REV_MIN	0
23 /*				1	   Counters support */
24 /*				2	   Comments support */
25 /*				3	   Forceadd support */
26 /*				4	   skbinfo support */
27 #define IPSET_TYPE_REV_MAX	5	/* bucketsize, initval support  */
28 
29 MODULE_LICENSE("GPL");
30 MODULE_AUTHOR("Jozsef Kadlecsik <kadlec@netfilter.org>");
31 IP_SET_MODULE_DESC("hash:ip", IPSET_TYPE_REV_MIN, IPSET_TYPE_REV_MAX);
32 MODULE_ALIAS("ip_set_hash:ip");
33 
34 /* Type specific function prefix */
35 #define HTYPE		hash_ip
36 #define IP_SET_HASH_WITH_NETMASK
37 
38 /* IPv4 variant */
39 
40 /* Member elements */
41 struct hash_ip4_elem {
42 	/* Zero valued IP addresses cannot be stored */
43 	__be32 ip;
44 };
45 
46 /* Common functions */
47 
48 static bool
49 hash_ip4_data_equal(const struct hash_ip4_elem *e1,
50 		    const struct hash_ip4_elem *e2,
51 		    u32 *multi)
52 {
53 	return e1->ip == e2->ip;
54 }
55 
56 static bool
57 hash_ip4_data_list(struct sk_buff *skb, const struct hash_ip4_elem *e)
58 {
59 	if (nla_put_ipaddr4(skb, IPSET_ATTR_IP, e->ip))
60 		goto nla_put_failure;
61 	return false;
62 
63 nla_put_failure:
64 	return true;
65 }
66 
67 static void
68 hash_ip4_data_next(struct hash_ip4_elem *next, const struct hash_ip4_elem *e)
69 {
70 	next->ip = e->ip;
71 }
72 
73 #define MTYPE		hash_ip4
74 #define HOST_MASK	32
75 #include "ip_set_hash_gen.h"
76 
77 static int
78 hash_ip4_kadt(struct ip_set *set, const struct sk_buff *skb,
79 	      const struct xt_action_param *par,
80 	      enum ipset_adt adt, struct ip_set_adt_opt *opt)
81 {
82 	const struct hash_ip4 *h = set->data;
83 	ipset_adtfn adtfn = set->variant->adt[adt];
84 	struct hash_ip4_elem e = { 0 };
85 	struct ip_set_ext ext = IP_SET_INIT_KEXT(skb, opt, set);
86 	__be32 ip;
87 
88 	ip4addrptr(skb, opt->flags & IPSET_DIM_ONE_SRC, &ip);
89 	ip &= ip_set_netmask(h->netmask);
90 	if (ip == 0)
91 		return -EINVAL;
92 
93 	e.ip = ip;
94 	return adtfn(set, &e, &ext, &opt->ext, opt->cmdflags);
95 }
96 
97 static int
98 hash_ip4_uadt(struct ip_set *set, struct nlattr *tb[],
99 	      enum ipset_adt adt, u32 *lineno, u32 flags, bool retried)
100 {
101 	const struct hash_ip4 *h = set->data;
102 	ipset_adtfn adtfn = set->variant->adt[adt];
103 	struct hash_ip4_elem e = { 0 };
104 	struct ip_set_ext ext = IP_SET_INIT_UEXT(set);
105 	u32 ip = 0, ip_to = 0, hosts;
106 	int ret = 0;
107 
108 	if (tb[IPSET_ATTR_LINENO])
109 		*lineno = nla_get_u32(tb[IPSET_ATTR_LINENO]);
110 
111 	if (unlikely(!tb[IPSET_ATTR_IP]))
112 		return -IPSET_ERR_PROTOCOL;
113 
114 	ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP], &ip);
115 	if (ret)
116 		return ret;
117 
118 	ret = ip_set_get_extensions(set, tb, &ext);
119 	if (ret)
120 		return ret;
121 
122 	ip &= ip_set_hostmask(h->netmask);
123 	e.ip = htonl(ip);
124 	if (e.ip == 0)
125 		return -IPSET_ERR_HASH_ELEM;
126 
127 	if (adt == IPSET_TEST)
128 		return adtfn(set, &e, &ext, &ext, flags);
129 
130 	ip_to = ip;
131 	if (tb[IPSET_ATTR_IP_TO]) {
132 		ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP_TO], &ip_to);
133 		if (ret)
134 			return ret;
135 		if (ip > ip_to) {
136 			if (ip_to == 0)
137 				return -IPSET_ERR_HASH_ELEM;
138 			swap(ip, ip_to);
139 		}
140 	} else if (tb[IPSET_ATTR_CIDR]) {
141 		u8 cidr = nla_get_u8(tb[IPSET_ATTR_CIDR]);
142 
143 		if (!cidr || cidr > HOST_MASK)
144 			return -IPSET_ERR_INVALID_CIDR;
145 		ip_set_mask_from_to(ip, ip_to, cidr);
146 	}
147 
148 	hosts = h->netmask == 32 ? 1 : 2 << (32 - h->netmask - 1);
149 
150 	/* 64bit division is not allowed on 32bit */
151 	if (((u64)ip_to - ip + 1) >> (32 - h->netmask) > IPSET_MAX_RANGE)
152 		return -ERANGE;
153 
154 	if (retried) {
155 		ip = ntohl(h->next.ip);
156 		e.ip = htonl(ip);
157 	}
158 	for (; ip <= ip_to;) {
159 		ret = adtfn(set, &e, &ext, &ext, flags);
160 		if (ret && !ip_set_eexist(ret, flags))
161 			return ret;
162 
163 		ip += hosts;
164 		e.ip = htonl(ip);
165 		if (e.ip == 0)
166 			return 0;
167 
168 		ret = 0;
169 	}
170 	return ret;
171 }
172 
173 /* IPv6 variant */
174 
175 /* Member elements */
176 struct hash_ip6_elem {
177 	union nf_inet_addr ip;
178 };
179 
180 /* Common functions */
181 
182 static bool
183 hash_ip6_data_equal(const struct hash_ip6_elem *ip1,
184 		    const struct hash_ip6_elem *ip2,
185 		    u32 *multi)
186 {
187 	return ipv6_addr_equal(&ip1->ip.in6, &ip2->ip.in6);
188 }
189 
190 static void
191 hash_ip6_netmask(union nf_inet_addr *ip, u8 prefix)
192 {
193 	ip6_netmask(ip, prefix);
194 }
195 
196 static bool
197 hash_ip6_data_list(struct sk_buff *skb, const struct hash_ip6_elem *e)
198 {
199 	if (nla_put_ipaddr6(skb, IPSET_ATTR_IP, &e->ip.in6))
200 		goto nla_put_failure;
201 	return false;
202 
203 nla_put_failure:
204 	return true;
205 }
206 
207 static void
208 hash_ip6_data_next(struct hash_ip6_elem *next, const struct hash_ip6_elem *e)
209 {
210 }
211 
212 #undef MTYPE
213 #undef HOST_MASK
214 
215 #define MTYPE		hash_ip6
216 #define HOST_MASK	128
217 
218 #define IP_SET_EMIT_CREATE
219 #include "ip_set_hash_gen.h"
220 
221 static int
222 hash_ip6_kadt(struct ip_set *set, const struct sk_buff *skb,
223 	      const struct xt_action_param *par,
224 	      enum ipset_adt adt, struct ip_set_adt_opt *opt)
225 {
226 	const struct hash_ip6 *h = set->data;
227 	ipset_adtfn adtfn = set->variant->adt[adt];
228 	struct hash_ip6_elem e = { { .all = { 0 } } };
229 	struct ip_set_ext ext = IP_SET_INIT_KEXT(skb, opt, set);
230 
231 	ip6addrptr(skb, opt->flags & IPSET_DIM_ONE_SRC, &e.ip.in6);
232 	hash_ip6_netmask(&e.ip, h->netmask);
233 	if (ipv6_addr_any(&e.ip.in6))
234 		return -EINVAL;
235 
236 	return adtfn(set, &e, &ext, &opt->ext, opt->cmdflags);
237 }
238 
239 static int
240 hash_ip6_uadt(struct ip_set *set, struct nlattr *tb[],
241 	      enum ipset_adt adt, u32 *lineno, u32 flags, bool retried)
242 {
243 	const struct hash_ip6 *h = set->data;
244 	ipset_adtfn adtfn = set->variant->adt[adt];
245 	struct hash_ip6_elem e = { { .all = { 0 } } };
246 	struct ip_set_ext ext = IP_SET_INIT_UEXT(set);
247 	int ret;
248 
249 	if (tb[IPSET_ATTR_LINENO])
250 		*lineno = nla_get_u32(tb[IPSET_ATTR_LINENO]);
251 
252 	if (unlikely(!tb[IPSET_ATTR_IP]))
253 		return -IPSET_ERR_PROTOCOL;
254 	if (unlikely(tb[IPSET_ATTR_IP_TO]))
255 		return -IPSET_ERR_HASH_RANGE_UNSUPPORTED;
256 	if (unlikely(tb[IPSET_ATTR_CIDR])) {
257 		u8 cidr = nla_get_u8(tb[IPSET_ATTR_CIDR]);
258 
259 		if (cidr != HOST_MASK)
260 			return -IPSET_ERR_INVALID_CIDR;
261 	}
262 
263 	ret = ip_set_get_ipaddr6(tb[IPSET_ATTR_IP], &e.ip);
264 	if (ret)
265 		return ret;
266 
267 	ret = ip_set_get_extensions(set, tb, &ext);
268 	if (ret)
269 		return ret;
270 
271 	hash_ip6_netmask(&e.ip, h->netmask);
272 	if (ipv6_addr_any(&e.ip.in6))
273 		return -IPSET_ERR_HASH_ELEM;
274 
275 	ret = adtfn(set, &e, &ext, &ext, flags);
276 
277 	return ip_set_eexist(ret, flags) ? 0 : ret;
278 }
279 
280 static struct ip_set_type hash_ip_type __read_mostly = {
281 	.name		= "hash:ip",
282 	.protocol	= IPSET_PROTOCOL,
283 	.features	= IPSET_TYPE_IP,
284 	.dimension	= IPSET_DIM_ONE,
285 	.family		= NFPROTO_UNSPEC,
286 	.revision_min	= IPSET_TYPE_REV_MIN,
287 	.revision_max	= IPSET_TYPE_REV_MAX,
288 	.create_flags[IPSET_TYPE_REV_MAX] = IPSET_CREATE_FLAG_BUCKETSIZE,
289 	.create		= hash_ip_create,
290 	.create_policy	= {
291 		[IPSET_ATTR_HASHSIZE]	= { .type = NLA_U32 },
292 		[IPSET_ATTR_MAXELEM]	= { .type = NLA_U32 },
293 		[IPSET_ATTR_INITVAL]	= { .type = NLA_U32 },
294 		[IPSET_ATTR_BUCKETSIZE]	= { .type = NLA_U8 },
295 		[IPSET_ATTR_RESIZE]	= { .type = NLA_U8  },
296 		[IPSET_ATTR_TIMEOUT]	= { .type = NLA_U32 },
297 		[IPSET_ATTR_NETMASK]	= { .type = NLA_U8  },
298 		[IPSET_ATTR_CADT_FLAGS]	= { .type = NLA_U32 },
299 	},
300 	.adt_policy	= {
301 		[IPSET_ATTR_IP]		= { .type = NLA_NESTED },
302 		[IPSET_ATTR_IP_TO]	= { .type = NLA_NESTED },
303 		[IPSET_ATTR_CIDR]	= { .type = NLA_U8 },
304 		[IPSET_ATTR_TIMEOUT]	= { .type = NLA_U32 },
305 		[IPSET_ATTR_LINENO]	= { .type = NLA_U32 },
306 		[IPSET_ATTR_BYTES]	= { .type = NLA_U64 },
307 		[IPSET_ATTR_PACKETS]	= { .type = NLA_U64 },
308 		[IPSET_ATTR_COMMENT]	= { .type = NLA_NUL_STRING,
309 					    .len  = IPSET_MAX_COMMENT_SIZE },
310 		[IPSET_ATTR_SKBMARK]	= { .type = NLA_U64 },
311 		[IPSET_ATTR_SKBPRIO]	= { .type = NLA_U32 },
312 		[IPSET_ATTR_SKBQUEUE]	= { .type = NLA_U16 },
313 	},
314 	.me		= THIS_MODULE,
315 };
316 
317 static int __init
318 hash_ip_init(void)
319 {
320 	return ip_set_type_register(&hash_ip_type);
321 }
322 
323 static void __exit
324 hash_ip_fini(void)
325 {
326 	rcu_barrier();
327 	ip_set_type_unregister(&hash_ip_type);
328 }
329 
330 module_init(hash_ip_init);
331 module_exit(hash_ip_fini);
332