1 /* Copyright (C) 2003-2013 Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
2  *
3  * This program is free software; you can redistribute it and/or modify
4  * it under the terms of the GNU General Public License version 2 as
5  * published by the Free Software Foundation.
6  */
7 
8 /* Kernel module implementing an IP set type: the hash:ip type */
9 
10 #include <linux/jhash.h>
11 #include <linux/module.h>
12 #include <linux/ip.h>
13 #include <linux/skbuff.h>
14 #include <linux/errno.h>
15 #include <linux/random.h>
16 #include <net/ip.h>
17 #include <net/ipv6.h>
18 #include <net/netlink.h>
19 #include <net/tcp.h>
20 
21 #include <linux/netfilter.h>
22 #include <linux/netfilter/ipset/pfxlen.h>
23 #include <linux/netfilter/ipset/ip_set.h>
24 #include <linux/netfilter/ipset/ip_set_hash.h>
25 
26 #define IPSET_TYPE_REV_MIN	0
27 /*				1	   Counters support */
28 /*				2	   Comments support */
29 /*				3	   Forceadd support */
30 #define IPSET_TYPE_REV_MAX	4	/* skbinfo support  */
31 
32 MODULE_LICENSE("GPL");
33 MODULE_AUTHOR("Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>");
34 IP_SET_MODULE_DESC("hash:ip", IPSET_TYPE_REV_MIN, IPSET_TYPE_REV_MAX);
35 MODULE_ALIAS("ip_set_hash:ip");
36 
37 /* Type specific function prefix */
38 #define HTYPE		hash_ip
39 #define IP_SET_HASH_WITH_NETMASK
40 
41 /* IPv4 variant */
42 
43 /* Member elements */
44 struct hash_ip4_elem {
45 	/* Zero valued IP addresses cannot be stored */
46 	__be32 ip;
47 };
48 
49 /* Common functions */
50 
51 static inline bool
hash_ip4_data_equal(const struct hash_ip4_elem * e1,const struct hash_ip4_elem * e2,u32 * multi)52 hash_ip4_data_equal(const struct hash_ip4_elem *e1,
53 		    const struct hash_ip4_elem *e2,
54 		    u32 *multi)
55 {
56 	return e1->ip == e2->ip;
57 }
58 
59 static inline bool
hash_ip4_data_list(struct sk_buff * skb,const struct hash_ip4_elem * e)60 hash_ip4_data_list(struct sk_buff *skb, const struct hash_ip4_elem *e)
61 {
62 	if (nla_put_ipaddr4(skb, IPSET_ATTR_IP, e->ip))
63 		goto nla_put_failure;
64 	return 0;
65 
66 nla_put_failure:
67 	return 1;
68 }
69 
70 static inline void
hash_ip4_data_next(struct hash_ip4_elem * next,const struct hash_ip4_elem * e)71 hash_ip4_data_next(struct hash_ip4_elem *next, const struct hash_ip4_elem *e)
72 {
73 	next->ip = e->ip;
74 }
75 
76 #define MTYPE		hash_ip4
77 #define PF		4
78 #define HOST_MASK	32
79 #include "ip_set_hash_gen.h"
80 
81 static int
hash_ip4_kadt(struct ip_set * set,const struct sk_buff * skb,const struct xt_action_param * par,enum ipset_adt adt,struct ip_set_adt_opt * opt)82 hash_ip4_kadt(struct ip_set *set, const struct sk_buff *skb,
83 	      const struct xt_action_param *par,
84 	      enum ipset_adt adt, struct ip_set_adt_opt *opt)
85 {
86 	const struct hash_ip *h = set->data;
87 	ipset_adtfn adtfn = set->variant->adt[adt];
88 	struct hash_ip4_elem e = { 0 };
89 	struct ip_set_ext ext = IP_SET_INIT_KEXT(skb, opt, set);
90 	__be32 ip;
91 
92 	ip4addrptr(skb, opt->flags & IPSET_DIM_ONE_SRC, &ip);
93 	ip &= ip_set_netmask(h->netmask);
94 	if (ip == 0)
95 		return -EINVAL;
96 
97 	e.ip = ip;
98 	return adtfn(set, &e, &ext, &opt->ext, opt->cmdflags);
99 }
100 
101 static int
hash_ip4_uadt(struct ip_set * set,struct nlattr * tb[],enum ipset_adt adt,u32 * lineno,u32 flags,bool retried)102 hash_ip4_uadt(struct ip_set *set, struct nlattr *tb[],
103 	      enum ipset_adt adt, u32 *lineno, u32 flags, bool retried)
104 {
105 	const struct hash_ip *h = set->data;
106 	ipset_adtfn adtfn = set->variant->adt[adt];
107 	struct hash_ip4_elem e = { 0 };
108 	struct ip_set_ext ext = IP_SET_INIT_UEXT(set);
109 	u32 ip = 0, ip_to = 0, hosts;
110 	int ret = 0;
111 
112 	if (unlikely(!tb[IPSET_ATTR_IP] ||
113 		     !ip_set_optattr_netorder(tb, IPSET_ATTR_TIMEOUT) ||
114 		     !ip_set_optattr_netorder(tb, IPSET_ATTR_PACKETS) ||
115 		     !ip_set_optattr_netorder(tb, IPSET_ATTR_BYTES)   ||
116 		     !ip_set_optattr_netorder(tb, IPSET_ATTR_SKBMARK) ||
117 		     !ip_set_optattr_netorder(tb, IPSET_ATTR_SKBPRIO) ||
118 		     !ip_set_optattr_netorder(tb, IPSET_ATTR_SKBQUEUE)))
119 		return -IPSET_ERR_PROTOCOL;
120 
121 	if (tb[IPSET_ATTR_LINENO])
122 		*lineno = nla_get_u32(tb[IPSET_ATTR_LINENO]);
123 
124 	ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP], &ip) ||
125 	      ip_set_get_extensions(set, tb, &ext);
126 	if (ret)
127 		return ret;
128 
129 	ip &= ip_set_hostmask(h->netmask);
130 
131 	if (adt == IPSET_TEST) {
132 		e.ip = htonl(ip);
133 		if (e.ip == 0)
134 			return -IPSET_ERR_HASH_ELEM;
135 		return adtfn(set, &e, &ext, &ext, flags);
136 	}
137 
138 	ip_to = ip;
139 	if (tb[IPSET_ATTR_IP_TO]) {
140 		ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP_TO], &ip_to);
141 		if (ret)
142 			return ret;
143 		if (ip > ip_to)
144 			swap(ip, ip_to);
145 	} else if (tb[IPSET_ATTR_CIDR]) {
146 		u8 cidr = nla_get_u8(tb[IPSET_ATTR_CIDR]);
147 
148 		if (!cidr || cidr > 32)
149 			return -IPSET_ERR_INVALID_CIDR;
150 		ip_set_mask_from_to(ip, ip_to, cidr);
151 	}
152 
153 	hosts = h->netmask == 32 ? 1 : 2 << (32 - h->netmask - 1);
154 
155 	if (retried)
156 		ip = ntohl(h->next.ip);
157 	for (; !before(ip_to, ip); ip += hosts) {
158 		e.ip = htonl(ip);
159 		if (e.ip == 0)
160 			return -IPSET_ERR_HASH_ELEM;
161 		ret = adtfn(set, &e, &ext, &ext, flags);
162 
163 		if (ret && !ip_set_eexist(ret, flags))
164 			return ret;
165 		else
166 			ret = 0;
167 	}
168 	return ret;
169 }
170 
171 /* IPv6 variant */
172 
173 /* Member elements */
174 struct hash_ip6_elem {
175 	union nf_inet_addr ip;
176 };
177 
178 /* Common functions */
179 
180 static inline bool
hash_ip6_data_equal(const struct hash_ip6_elem * ip1,const struct hash_ip6_elem * ip2,u32 * multi)181 hash_ip6_data_equal(const struct hash_ip6_elem *ip1,
182 		    const struct hash_ip6_elem *ip2,
183 		    u32 *multi)
184 {
185 	return ipv6_addr_equal(&ip1->ip.in6, &ip2->ip.in6);
186 }
187 
188 static inline void
hash_ip6_netmask(union nf_inet_addr * ip,u8 prefix)189 hash_ip6_netmask(union nf_inet_addr *ip, u8 prefix)
190 {
191 	ip6_netmask(ip, prefix);
192 }
193 
194 static bool
hash_ip6_data_list(struct sk_buff * skb,const struct hash_ip6_elem * e)195 hash_ip6_data_list(struct sk_buff *skb, const struct hash_ip6_elem *e)
196 {
197 	if (nla_put_ipaddr6(skb, IPSET_ATTR_IP, &e->ip.in6))
198 		goto nla_put_failure;
199 	return 0;
200 
201 nla_put_failure:
202 	return 1;
203 }
204 
205 static inline void
hash_ip6_data_next(struct hash_ip4_elem * next,const struct hash_ip6_elem * e)206 hash_ip6_data_next(struct hash_ip4_elem *next, const struct hash_ip6_elem *e)
207 {
208 }
209 
210 #undef MTYPE
211 #undef PF
212 #undef HOST_MASK
213 #undef HKEY_DATALEN
214 
215 #define MTYPE		hash_ip6
216 #define PF		6
217 #define HOST_MASK	128
218 
219 #define IP_SET_EMIT_CREATE
220 #include "ip_set_hash_gen.h"
221 
222 static int
hash_ip6_kadt(struct ip_set * set,const struct sk_buff * skb,const struct xt_action_param * par,enum ipset_adt adt,struct ip_set_adt_opt * opt)223 hash_ip6_kadt(struct ip_set *set, const struct sk_buff *skb,
224 	      const struct xt_action_param *par,
225 	      enum ipset_adt adt, struct ip_set_adt_opt *opt)
226 {
227 	const struct hash_ip *h = set->data;
228 	ipset_adtfn adtfn = set->variant->adt[adt];
229 	struct hash_ip6_elem e = { { .all = { 0 } } };
230 	struct ip_set_ext ext = IP_SET_INIT_KEXT(skb, opt, set);
231 
232 	ip6addrptr(skb, opt->flags & IPSET_DIM_ONE_SRC, &e.ip.in6);
233 	hash_ip6_netmask(&e.ip, h->netmask);
234 	if (ipv6_addr_any(&e.ip.in6))
235 		return -EINVAL;
236 
237 	return adtfn(set, &e, &ext, &opt->ext, opt->cmdflags);
238 }
239 
240 static int
hash_ip6_uadt(struct ip_set * set,struct nlattr * tb[],enum ipset_adt adt,u32 * lineno,u32 flags,bool retried)241 hash_ip6_uadt(struct ip_set *set, struct nlattr *tb[],
242 	      enum ipset_adt adt, u32 *lineno, u32 flags, bool retried)
243 {
244 	const struct hash_ip *h = set->data;
245 	ipset_adtfn adtfn = set->variant->adt[adt];
246 	struct hash_ip6_elem e = { { .all = { 0 } } };
247 	struct ip_set_ext ext = IP_SET_INIT_UEXT(set);
248 	int ret;
249 
250 	if (unlikely(!tb[IPSET_ATTR_IP] ||
251 		     !ip_set_optattr_netorder(tb, IPSET_ATTR_TIMEOUT) ||
252 		     !ip_set_optattr_netorder(tb, IPSET_ATTR_PACKETS) ||
253 		     !ip_set_optattr_netorder(tb, IPSET_ATTR_BYTES) ||
254 		     !ip_set_optattr_netorder(tb, IPSET_ATTR_SKBMARK) ||
255 		     !ip_set_optattr_netorder(tb, IPSET_ATTR_SKBPRIO) ||
256 		     !ip_set_optattr_netorder(tb, IPSET_ATTR_SKBQUEUE) ||
257 		     tb[IPSET_ATTR_IP_TO] ||
258 		     tb[IPSET_ATTR_CIDR]))
259 		return -IPSET_ERR_PROTOCOL;
260 
261 	if (tb[IPSET_ATTR_LINENO])
262 		*lineno = nla_get_u32(tb[IPSET_ATTR_LINENO]);
263 
264 	ret = ip_set_get_ipaddr6(tb[IPSET_ATTR_IP], &e.ip) ||
265 	      ip_set_get_extensions(set, tb, &ext);
266 	if (ret)
267 		return ret;
268 
269 	hash_ip6_netmask(&e.ip, h->netmask);
270 	if (ipv6_addr_any(&e.ip.in6))
271 		return -IPSET_ERR_HASH_ELEM;
272 
273 	ret = adtfn(set, &e, &ext, &ext, flags);
274 
275 	return ip_set_eexist(ret, flags) ? 0 : ret;
276 }
277 
278 static struct ip_set_type hash_ip_type __read_mostly = {
279 	.name		= "hash:ip",
280 	.protocol	= IPSET_PROTOCOL,
281 	.features	= IPSET_TYPE_IP,
282 	.dimension	= IPSET_DIM_ONE,
283 	.family		= NFPROTO_UNSPEC,
284 	.revision_min	= IPSET_TYPE_REV_MIN,
285 	.revision_max	= IPSET_TYPE_REV_MAX,
286 	.create		= hash_ip_create,
287 	.create_policy	= {
288 		[IPSET_ATTR_HASHSIZE]	= { .type = NLA_U32 },
289 		[IPSET_ATTR_MAXELEM]	= { .type = NLA_U32 },
290 		[IPSET_ATTR_PROBES]	= { .type = NLA_U8 },
291 		[IPSET_ATTR_RESIZE]	= { .type = NLA_U8  },
292 		[IPSET_ATTR_TIMEOUT]	= { .type = NLA_U32 },
293 		[IPSET_ATTR_NETMASK]	= { .type = NLA_U8  },
294 		[IPSET_ATTR_CADT_FLAGS]	= { .type = NLA_U32 },
295 	},
296 	.adt_policy	= {
297 		[IPSET_ATTR_IP]		= { .type = NLA_NESTED },
298 		[IPSET_ATTR_IP_TO]	= { .type = NLA_NESTED },
299 		[IPSET_ATTR_CIDR]	= { .type = NLA_U8 },
300 		[IPSET_ATTR_TIMEOUT]	= { .type = NLA_U32 },
301 		[IPSET_ATTR_LINENO]	= { .type = NLA_U32 },
302 		[IPSET_ATTR_BYTES]	= { .type = NLA_U64 },
303 		[IPSET_ATTR_PACKETS]	= { .type = NLA_U64 },
304 		[IPSET_ATTR_COMMENT]	= { .type = NLA_NUL_STRING },
305 		[IPSET_ATTR_SKBMARK]	= { .type = NLA_U64 },
306 		[IPSET_ATTR_SKBPRIO]	= { .type = NLA_U32 },
307 		[IPSET_ATTR_SKBQUEUE]	= { .type = NLA_U16 },
308 	},
309 	.me		= THIS_MODULE,
310 };
311 
312 static int __init
hash_ip_init(void)313 hash_ip_init(void)
314 {
315 	return ip_set_type_register(&hash_ip_type);
316 }
317 
318 static void __exit
hash_ip_fini(void)319 hash_ip_fini(void)
320 {
321 	ip_set_type_unregister(&hash_ip_type);
322 }
323 
324 module_init(hash_ip_init);
325 module_exit(hash_ip_fini);
326