1 /* Copyright (C) 2003-2013 Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
2  * Copyright (C) 2013 Oliver Smith <oliver@8.c.9.b.0.7.4.0.1.0.0.2.ip6.arpa>
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License version 2 as
6  * published by the Free Software Foundation.
7  */
8 
9 /* Kernel module implementing an IP set type: the hash:net type */
10 
11 #include <linux/jhash.h>
12 #include <linux/module.h>
13 #include <linux/ip.h>
14 #include <linux/skbuff.h>
15 #include <linux/errno.h>
16 #include <linux/random.h>
17 #include <net/ip.h>
18 #include <net/ipv6.h>
19 #include <net/netlink.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	   Forceadd support added */
28 #define IPSET_TYPE_REV_MAX	2	/* skbinfo support added */
29 
30 MODULE_LICENSE("GPL");
31 MODULE_AUTHOR("Oliver Smith <oliver@8.c.9.b.0.7.4.0.1.0.0.2.ip6.arpa>");
32 IP_SET_MODULE_DESC("hash:net,net", IPSET_TYPE_REV_MIN, IPSET_TYPE_REV_MAX);
33 MODULE_ALIAS("ip_set_hash:net,net");
34 
35 /* Type specific function prefix */
36 #define HTYPE		hash_netnet
37 #define IP_SET_HASH_WITH_NETS
38 #define IPSET_NET_COUNT 2
39 
40 /* IPv4 variants */
41 
42 /* Member elements  */
43 struct hash_netnet4_elem {
44 	union {
45 		__be32 ip[2];
46 		__be64 ipcmp;
47 	};
48 	u8 nomatch;
49 	u8 padding;
50 	union {
51 		u8 cidr[2];
52 		u16 ccmp;
53 	};
54 };
55 
56 /* Common functions */
57 
58 static inline bool
59 hash_netnet4_data_equal(const struct hash_netnet4_elem *ip1,
60 			const struct hash_netnet4_elem *ip2,
61 			u32 *multi)
62 {
63 	return ip1->ipcmp == ip2->ipcmp &&
64 	       ip1->ccmp == ip2->ccmp;
65 }
66 
67 static inline int
68 hash_netnet4_do_data_match(const struct hash_netnet4_elem *elem)
69 {
70 	return elem->nomatch ? -ENOTEMPTY : 1;
71 }
72 
73 static inline void
74 hash_netnet4_data_set_flags(struct hash_netnet4_elem *elem, u32 flags)
75 {
76 	elem->nomatch = (flags >> 16) & IPSET_FLAG_NOMATCH;
77 }
78 
79 static inline void
80 hash_netnet4_data_reset_flags(struct hash_netnet4_elem *elem, u8 *flags)
81 {
82 	swap(*flags, elem->nomatch);
83 }
84 
85 static inline void
86 hash_netnet4_data_reset_elem(struct hash_netnet4_elem *elem,
87 			     struct hash_netnet4_elem *orig)
88 {
89 	elem->ip[1] = orig->ip[1];
90 }
91 
92 static inline void
93 hash_netnet4_data_netmask(struct hash_netnet4_elem *elem, u8 cidr, bool inner)
94 {
95 	if (inner) {
96 		elem->ip[1] &= ip_set_netmask(cidr);
97 		elem->cidr[1] = cidr;
98 	} else {
99 		elem->ip[0] &= ip_set_netmask(cidr);
100 		elem->cidr[0] = cidr;
101 	}
102 }
103 
104 static bool
105 hash_netnet4_data_list(struct sk_buff *skb,
106 		       const struct hash_netnet4_elem *data)
107 {
108 	u32 flags = data->nomatch ? IPSET_FLAG_NOMATCH : 0;
109 
110 	if (nla_put_ipaddr4(skb, IPSET_ATTR_IP, data->ip[0]) ||
111 	    nla_put_ipaddr4(skb, IPSET_ATTR_IP2, data->ip[1]) ||
112 	    nla_put_u8(skb, IPSET_ATTR_CIDR, data->cidr[0]) ||
113 	    nla_put_u8(skb, IPSET_ATTR_CIDR2, data->cidr[1]) ||
114 	    (flags &&
115 	     nla_put_net32(skb, IPSET_ATTR_CADT_FLAGS, htonl(flags))))
116 		goto nla_put_failure;
117 	return false;
118 
119 nla_put_failure:
120 	return true;
121 }
122 
123 static inline void
124 hash_netnet4_data_next(struct hash_netnet4_elem *next,
125 		       const struct hash_netnet4_elem *d)
126 {
127 	next->ipcmp = d->ipcmp;
128 }
129 
130 #define MTYPE		hash_netnet4
131 #define HOST_MASK	32
132 #include "ip_set_hash_gen.h"
133 
134 static void
135 hash_netnet4_init(struct hash_netnet4_elem *e)
136 {
137 	e->cidr[0] = HOST_MASK;
138 	e->cidr[1] = HOST_MASK;
139 }
140 
141 static int
142 hash_netnet4_kadt(struct ip_set *set, const struct sk_buff *skb,
143 		  const struct xt_action_param *par,
144 		  enum ipset_adt adt, struct ip_set_adt_opt *opt)
145 {
146 	const struct hash_netnet *h = set->data;
147 	ipset_adtfn adtfn = set->variant->adt[adt];
148 	struct hash_netnet4_elem e = { };
149 	struct ip_set_ext ext = IP_SET_INIT_KEXT(skb, opt, set);
150 
151 	e.cidr[0] = INIT_CIDR(h->nets[0].cidr[0], HOST_MASK);
152 	e.cidr[1] = INIT_CIDR(h->nets[0].cidr[1], HOST_MASK);
153 	if (adt == IPSET_TEST)
154 		e.ccmp = (HOST_MASK << (sizeof(e.cidr[0]) * 8)) | HOST_MASK;
155 
156 	ip4addrptr(skb, opt->flags & IPSET_DIM_ONE_SRC, &e.ip[0]);
157 	ip4addrptr(skb, opt->flags & IPSET_DIM_TWO_SRC, &e.ip[1]);
158 	e.ip[0] &= ip_set_netmask(e.cidr[0]);
159 	e.ip[1] &= ip_set_netmask(e.cidr[1]);
160 
161 	return adtfn(set, &e, &ext, &opt->ext, opt->cmdflags);
162 }
163 
164 static int
165 hash_netnet4_uadt(struct ip_set *set, struct nlattr *tb[],
166 		  enum ipset_adt adt, u32 *lineno, u32 flags, bool retried)
167 {
168 	const struct hash_netnet *h = set->data;
169 	ipset_adtfn adtfn = set->variant->adt[adt];
170 	struct hash_netnet4_elem e = { };
171 	struct ip_set_ext ext = IP_SET_INIT_UEXT(set);
172 	u32 ip = 0, ip_to = 0, last;
173 	u32 ip2 = 0, ip2_from = 0, ip2_to = 0, last2;
174 	int ret;
175 
176 	if (tb[IPSET_ATTR_LINENO])
177 		*lineno = nla_get_u32(tb[IPSET_ATTR_LINENO]);
178 
179 	hash_netnet4_init(&e);
180 	if (unlikely(!tb[IPSET_ATTR_IP] || !tb[IPSET_ATTR_IP2] ||
181 		     !ip_set_optattr_netorder(tb, IPSET_ATTR_CADT_FLAGS)))
182 		return -IPSET_ERR_PROTOCOL;
183 
184 	ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP], &ip);
185 	if (ret)
186 		return ret;
187 
188 	ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP2], &ip2_from);
189 	if (ret)
190 		return ret;
191 
192 	ret = ip_set_get_extensions(set, tb, &ext);
193 	if (ret)
194 		return ret;
195 
196 	if (tb[IPSET_ATTR_CIDR]) {
197 		e.cidr[0] = nla_get_u8(tb[IPSET_ATTR_CIDR]);
198 		if (!e.cidr[0] || e.cidr[0] > HOST_MASK)
199 			return -IPSET_ERR_INVALID_CIDR;
200 	}
201 
202 	if (tb[IPSET_ATTR_CIDR2]) {
203 		e.cidr[1] = nla_get_u8(tb[IPSET_ATTR_CIDR2]);
204 		if (!e.cidr[1] || e.cidr[1] > HOST_MASK)
205 			return -IPSET_ERR_INVALID_CIDR;
206 	}
207 
208 	if (tb[IPSET_ATTR_CADT_FLAGS]) {
209 		u32 cadt_flags = ip_set_get_h32(tb[IPSET_ATTR_CADT_FLAGS]);
210 
211 		if (cadt_flags & IPSET_FLAG_NOMATCH)
212 			flags |= (IPSET_FLAG_NOMATCH << 16);
213 	}
214 
215 	if (adt == IPSET_TEST || !(tb[IPSET_ATTR_IP_TO] ||
216 				   tb[IPSET_ATTR_IP2_TO])) {
217 		e.ip[0] = htonl(ip & ip_set_hostmask(e.cidr[0]));
218 		e.ip[1] = htonl(ip2_from & ip_set_hostmask(e.cidr[1]));
219 		ret = adtfn(set, &e, &ext, &ext, flags);
220 		return ip_set_enomatch(ret, flags, adt, set) ? -ret :
221 		       ip_set_eexist(ret, flags) ? 0 : ret;
222 	}
223 
224 	ip_to = ip;
225 	if (tb[IPSET_ATTR_IP_TO]) {
226 		ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP_TO], &ip_to);
227 		if (ret)
228 			return ret;
229 		if (ip_to < ip)
230 			swap(ip, ip_to);
231 		if (unlikely(ip + UINT_MAX == ip_to))
232 			return -IPSET_ERR_HASH_RANGE;
233 	} else {
234 		ip_set_mask_from_to(ip, ip_to, e.cidr[0]);
235 	}
236 
237 	ip2_to = ip2_from;
238 	if (tb[IPSET_ATTR_IP2_TO]) {
239 		ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP2_TO], &ip2_to);
240 		if (ret)
241 			return ret;
242 		if (ip2_to < ip2_from)
243 			swap(ip2_from, ip2_to);
244 		if (unlikely(ip2_from + UINT_MAX == ip2_to))
245 			return -IPSET_ERR_HASH_RANGE;
246 	} else {
247 		ip_set_mask_from_to(ip2_from, ip2_to, e.cidr[1]);
248 	}
249 
250 	if (retried)
251 		ip = ntohl(h->next.ip[0]);
252 
253 	while (!after(ip, ip_to)) {
254 		e.ip[0] = htonl(ip);
255 		last = ip_set_range_to_cidr(ip, ip_to, &e.cidr[0]);
256 		ip2 = (retried &&
257 		       ip == ntohl(h->next.ip[0])) ? ntohl(h->next.ip[1])
258 						   : ip2_from;
259 		while (!after(ip2, ip2_to)) {
260 			e.ip[1] = htonl(ip2);
261 			last2 = ip_set_range_to_cidr(ip2, ip2_to, &e.cidr[1]);
262 			ret = adtfn(set, &e, &ext, &ext, flags);
263 			if (ret && !ip_set_eexist(ret, flags))
264 				return ret;
265 
266 			ret = 0;
267 			ip2 = last2 + 1;
268 		}
269 		ip = last + 1;
270 	}
271 	return ret;
272 }
273 
274 /* IPv6 variants */
275 
276 struct hash_netnet6_elem {
277 	union nf_inet_addr ip[2];
278 	u8 nomatch;
279 	u8 padding;
280 	union {
281 		u8 cidr[2];
282 		u16 ccmp;
283 	};
284 };
285 
286 /* Common functions */
287 
288 static inline bool
289 hash_netnet6_data_equal(const struct hash_netnet6_elem *ip1,
290 			const struct hash_netnet6_elem *ip2,
291 			u32 *multi)
292 {
293 	return ipv6_addr_equal(&ip1->ip[0].in6, &ip2->ip[0].in6) &&
294 	       ipv6_addr_equal(&ip1->ip[1].in6, &ip2->ip[1].in6) &&
295 	       ip1->ccmp == ip2->ccmp;
296 }
297 
298 static inline int
299 hash_netnet6_do_data_match(const struct hash_netnet6_elem *elem)
300 {
301 	return elem->nomatch ? -ENOTEMPTY : 1;
302 }
303 
304 static inline void
305 hash_netnet6_data_set_flags(struct hash_netnet6_elem *elem, u32 flags)
306 {
307 	elem->nomatch = (flags >> 16) & IPSET_FLAG_NOMATCH;
308 }
309 
310 static inline void
311 hash_netnet6_data_reset_flags(struct hash_netnet6_elem *elem, u8 *flags)
312 {
313 	swap(*flags, elem->nomatch);
314 }
315 
316 static inline void
317 hash_netnet6_data_reset_elem(struct hash_netnet6_elem *elem,
318 			     struct hash_netnet6_elem *orig)
319 {
320 	elem->ip[1] = orig->ip[1];
321 }
322 
323 static inline void
324 hash_netnet6_data_netmask(struct hash_netnet6_elem *elem, u8 cidr, bool inner)
325 {
326 	if (inner) {
327 		ip6_netmask(&elem->ip[1], cidr);
328 		elem->cidr[1] = cidr;
329 	} else {
330 		ip6_netmask(&elem->ip[0], cidr);
331 		elem->cidr[0] = cidr;
332 	}
333 }
334 
335 static bool
336 hash_netnet6_data_list(struct sk_buff *skb,
337 		       const struct hash_netnet6_elem *data)
338 {
339 	u32 flags = data->nomatch ? IPSET_FLAG_NOMATCH : 0;
340 
341 	if (nla_put_ipaddr6(skb, IPSET_ATTR_IP, &data->ip[0].in6) ||
342 	    nla_put_ipaddr6(skb, IPSET_ATTR_IP2, &data->ip[1].in6) ||
343 	    nla_put_u8(skb, IPSET_ATTR_CIDR, data->cidr[0]) ||
344 	    nla_put_u8(skb, IPSET_ATTR_CIDR2, data->cidr[1]) ||
345 	    (flags &&
346 	     nla_put_net32(skb, IPSET_ATTR_CADT_FLAGS, htonl(flags))))
347 		goto nla_put_failure;
348 	return false;
349 
350 nla_put_failure:
351 	return true;
352 }
353 
354 static inline void
355 hash_netnet6_data_next(struct hash_netnet4_elem *next,
356 		       const struct hash_netnet6_elem *d)
357 {
358 }
359 
360 #undef MTYPE
361 #undef HOST_MASK
362 
363 #define MTYPE		hash_netnet6
364 #define HOST_MASK	128
365 #define IP_SET_EMIT_CREATE
366 #include "ip_set_hash_gen.h"
367 
368 static void
369 hash_netnet6_init(struct hash_netnet6_elem *e)
370 {
371 	e->cidr[0] = HOST_MASK;
372 	e->cidr[1] = HOST_MASK;
373 }
374 
375 static int
376 hash_netnet6_kadt(struct ip_set *set, const struct sk_buff *skb,
377 		  const struct xt_action_param *par,
378 		  enum ipset_adt adt, struct ip_set_adt_opt *opt)
379 {
380 	const struct hash_netnet *h = set->data;
381 	ipset_adtfn adtfn = set->variant->adt[adt];
382 	struct hash_netnet6_elem e = { };
383 	struct ip_set_ext ext = IP_SET_INIT_KEXT(skb, opt, set);
384 
385 	e.cidr[0] = INIT_CIDR(h->nets[0].cidr[0], HOST_MASK);
386 	e.cidr[1] = INIT_CIDR(h->nets[0].cidr[1], HOST_MASK);
387 	if (adt == IPSET_TEST)
388 		e.ccmp = (HOST_MASK << (sizeof(u8) * 8)) | HOST_MASK;
389 
390 	ip6addrptr(skb, opt->flags & IPSET_DIM_ONE_SRC, &e.ip[0].in6);
391 	ip6addrptr(skb, opt->flags & IPSET_DIM_TWO_SRC, &e.ip[1].in6);
392 	ip6_netmask(&e.ip[0], e.cidr[0]);
393 	ip6_netmask(&e.ip[1], e.cidr[1]);
394 
395 	return adtfn(set, &e, &ext, &opt->ext, opt->cmdflags);
396 }
397 
398 static int
399 hash_netnet6_uadt(struct ip_set *set, struct nlattr *tb[],
400 		  enum ipset_adt adt, u32 *lineno, u32 flags, bool retried)
401 {
402 	ipset_adtfn adtfn = set->variant->adt[adt];
403 	struct hash_netnet6_elem e = { };
404 	struct ip_set_ext ext = IP_SET_INIT_UEXT(set);
405 	int ret;
406 
407 	if (tb[IPSET_ATTR_LINENO])
408 		*lineno = nla_get_u32(tb[IPSET_ATTR_LINENO]);
409 
410 	hash_netnet6_init(&e);
411 	if (unlikely(!tb[IPSET_ATTR_IP] || !tb[IPSET_ATTR_IP2] ||
412 		     !ip_set_optattr_netorder(tb, IPSET_ATTR_CADT_FLAGS)))
413 		return -IPSET_ERR_PROTOCOL;
414 	if (unlikely(tb[IPSET_ATTR_IP_TO] || tb[IPSET_ATTR_IP2_TO]))
415 		return -IPSET_ERR_HASH_RANGE_UNSUPPORTED;
416 
417 	ret = ip_set_get_ipaddr6(tb[IPSET_ATTR_IP], &e.ip[0]);
418 	if (ret)
419 		return ret;
420 
421 	ret = ip_set_get_ipaddr6(tb[IPSET_ATTR_IP2], &e.ip[1]);
422 	if (ret)
423 		return ret;
424 
425 	ret = ip_set_get_extensions(set, tb, &ext);
426 	if (ret)
427 		return ret;
428 
429 	if (tb[IPSET_ATTR_CIDR]) {
430 		e.cidr[0] = nla_get_u8(tb[IPSET_ATTR_CIDR]);
431 		if (!e.cidr[0] || e.cidr[0] > HOST_MASK)
432 			return -IPSET_ERR_INVALID_CIDR;
433 	}
434 
435 	if (tb[IPSET_ATTR_CIDR2]) {
436 		e.cidr[1] = nla_get_u8(tb[IPSET_ATTR_CIDR2]);
437 		if (!e.cidr[1] || e.cidr[1] > HOST_MASK)
438 			return -IPSET_ERR_INVALID_CIDR;
439 	}
440 
441 	ip6_netmask(&e.ip[0], e.cidr[0]);
442 	ip6_netmask(&e.ip[1], e.cidr[1]);
443 
444 	if (tb[IPSET_ATTR_CADT_FLAGS]) {
445 		u32 cadt_flags = ip_set_get_h32(tb[IPSET_ATTR_CADT_FLAGS]);
446 
447 		if (cadt_flags & IPSET_FLAG_NOMATCH)
448 			flags |= (IPSET_FLAG_NOMATCH << 16);
449 	}
450 
451 	ret = adtfn(set, &e, &ext, &ext, flags);
452 
453 	return ip_set_enomatch(ret, flags, adt, set) ? -ret :
454 	       ip_set_eexist(ret, flags) ? 0 : ret;
455 }
456 
457 static struct ip_set_type hash_netnet_type __read_mostly = {
458 	.name		= "hash:net,net",
459 	.protocol	= IPSET_PROTOCOL,
460 	.features	= IPSET_TYPE_IP | IPSET_TYPE_IP2 | IPSET_TYPE_NOMATCH,
461 	.dimension	= IPSET_DIM_TWO,
462 	.family		= NFPROTO_UNSPEC,
463 	.revision_min	= IPSET_TYPE_REV_MIN,
464 	.revision_max	= IPSET_TYPE_REV_MAX,
465 	.create		= hash_netnet_create,
466 	.create_policy	= {
467 		[IPSET_ATTR_HASHSIZE]	= { .type = NLA_U32 },
468 		[IPSET_ATTR_MAXELEM]	= { .type = NLA_U32 },
469 		[IPSET_ATTR_PROBES]	= { .type = NLA_U8 },
470 		[IPSET_ATTR_RESIZE]	= { .type = NLA_U8  },
471 		[IPSET_ATTR_TIMEOUT]	= { .type = NLA_U32 },
472 		[IPSET_ATTR_CADT_FLAGS]	= { .type = NLA_U32 },
473 	},
474 	.adt_policy	= {
475 		[IPSET_ATTR_IP]		= { .type = NLA_NESTED },
476 		[IPSET_ATTR_IP_TO]	= { .type = NLA_NESTED },
477 		[IPSET_ATTR_IP2]	= { .type = NLA_NESTED },
478 		[IPSET_ATTR_IP2_TO]	= { .type = NLA_NESTED },
479 		[IPSET_ATTR_CIDR]	= { .type = NLA_U8 },
480 		[IPSET_ATTR_CIDR2]	= { .type = NLA_U8 },
481 		[IPSET_ATTR_TIMEOUT]	= { .type = NLA_U32 },
482 		[IPSET_ATTR_CADT_FLAGS]	= { .type = NLA_U32 },
483 		[IPSET_ATTR_BYTES]	= { .type = NLA_U64 },
484 		[IPSET_ATTR_PACKETS]	= { .type = NLA_U64 },
485 		[IPSET_ATTR_COMMENT]	= { .type = NLA_NUL_STRING,
486 					    .len  = IPSET_MAX_COMMENT_SIZE },
487 		[IPSET_ATTR_SKBMARK]	= { .type = NLA_U64 },
488 		[IPSET_ATTR_SKBPRIO]	= { .type = NLA_U32 },
489 		[IPSET_ATTR_SKBQUEUE]	= { .type = NLA_U16 },
490 	},
491 	.me		= THIS_MODULE,
492 };
493 
494 static int __init
495 hash_netnet_init(void)
496 {
497 	return ip_set_type_register(&hash_netnet_type);
498 }
499 
500 static void __exit
501 hash_netnet_fini(void)
502 {
503 	rcu_barrier();
504 	ip_set_type_unregister(&hash_netnet_type);
505 }
506 
507 module_init(hash_netnet_init);
508 module_exit(hash_netnet_fini);
509