1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Copyright (C) 2003-2013 Jozsef Kadlecsik <kadlec@netfilter.org>
3  * Copyright (C) 2013 Oliver Smith <oliver@8.c.9.b.0.7.4.0.1.0.0.2.ip6.arpa>
4  */
5 
6 /* Kernel module implementing an IP set type: the hash:net type */
7 
8 #include <linux/jhash.h>
9 #include <linux/module.h>
10 #include <linux/ip.h>
11 #include <linux/skbuff.h>
12 #include <linux/errno.h>
13 #include <linux/random.h>
14 #include <net/ip.h>
15 #include <net/ipv6.h>
16 #include <net/netlink.h>
17 
18 #include <linux/netfilter.h>
19 #include <linux/netfilter/ipset/pfxlen.h>
20 #include <linux/netfilter/ipset/ip_set.h>
21 #include <linux/netfilter/ipset/ip_set_hash.h>
22 
23 #define IPSET_TYPE_REV_MIN	0
24 /*				1	   Forceadd support added */
25 /*				2	   skbinfo support added */
26 #define IPSET_TYPE_REV_MAX	3	/* bucketsize, initval support added */
27 
28 MODULE_LICENSE("GPL");
29 MODULE_AUTHOR("Oliver Smith <oliver@8.c.9.b.0.7.4.0.1.0.0.2.ip6.arpa>");
30 IP_SET_MODULE_DESC("hash:net,net", IPSET_TYPE_REV_MIN, IPSET_TYPE_REV_MAX);
31 MODULE_ALIAS("ip_set_hash:net,net");
32 
33 /* Type specific function prefix */
34 #define HTYPE		hash_netnet
35 #define IP_SET_HASH_WITH_NETS
36 #define IPSET_NET_COUNT 2
37 
38 /* IPv4 variants */
39 
40 /* Member elements  */
41 struct hash_netnet4_elem {
42 	union {
43 		__be32 ip[2];
44 		__be64 ipcmp;
45 	};
46 	u8 nomatch;
47 	u8 padding;
48 	union {
49 		u8 cidr[2];
50 		u16 ccmp;
51 	};
52 };
53 
54 /* Common functions */
55 
56 static bool
57 hash_netnet4_data_equal(const struct hash_netnet4_elem *ip1,
58 			const struct hash_netnet4_elem *ip2,
59 			u32 *multi)
60 {
61 	return ip1->ipcmp == ip2->ipcmp &&
62 	       ip1->ccmp == ip2->ccmp;
63 }
64 
65 static int
66 hash_netnet4_do_data_match(const struct hash_netnet4_elem *elem)
67 {
68 	return elem->nomatch ? -ENOTEMPTY : 1;
69 }
70 
71 static void
72 hash_netnet4_data_set_flags(struct hash_netnet4_elem *elem, u32 flags)
73 {
74 	elem->nomatch = (flags >> 16) & IPSET_FLAG_NOMATCH;
75 }
76 
77 static void
78 hash_netnet4_data_reset_flags(struct hash_netnet4_elem *elem, u8 *flags)
79 {
80 	swap(*flags, elem->nomatch);
81 }
82 
83 static void
84 hash_netnet4_data_reset_elem(struct hash_netnet4_elem *elem,
85 			     struct hash_netnet4_elem *orig)
86 {
87 	elem->ip[1] = orig->ip[1];
88 }
89 
90 static void
91 hash_netnet4_data_netmask(struct hash_netnet4_elem *elem, u8 cidr, bool inner)
92 {
93 	if (inner) {
94 		elem->ip[1] &= ip_set_netmask(cidr);
95 		elem->cidr[1] = cidr;
96 	} else {
97 		elem->ip[0] &= ip_set_netmask(cidr);
98 		elem->cidr[0] = cidr;
99 	}
100 }
101 
102 static bool
103 hash_netnet4_data_list(struct sk_buff *skb,
104 		       const struct hash_netnet4_elem *data)
105 {
106 	u32 flags = data->nomatch ? IPSET_FLAG_NOMATCH : 0;
107 
108 	if (nla_put_ipaddr4(skb, IPSET_ATTR_IP, data->ip[0]) ||
109 	    nla_put_ipaddr4(skb, IPSET_ATTR_IP2, data->ip[1]) ||
110 	    nla_put_u8(skb, IPSET_ATTR_CIDR, data->cidr[0]) ||
111 	    nla_put_u8(skb, IPSET_ATTR_CIDR2, data->cidr[1]) ||
112 	    (flags &&
113 	     nla_put_net32(skb, IPSET_ATTR_CADT_FLAGS, htonl(flags))))
114 		goto nla_put_failure;
115 	return false;
116 
117 nla_put_failure:
118 	return true;
119 }
120 
121 static void
122 hash_netnet4_data_next(struct hash_netnet4_elem *next,
123 		       const struct hash_netnet4_elem *d)
124 {
125 	next->ipcmp = d->ipcmp;
126 }
127 
128 #define MTYPE		hash_netnet4
129 #define HOST_MASK	32
130 #include "ip_set_hash_gen.h"
131 
132 static void
133 hash_netnet4_init(struct hash_netnet4_elem *e)
134 {
135 	e->cidr[0] = HOST_MASK;
136 	e->cidr[1] = HOST_MASK;
137 }
138 
139 static int
140 hash_netnet4_kadt(struct ip_set *set, const struct sk_buff *skb,
141 		  const struct xt_action_param *par,
142 		  enum ipset_adt adt, struct ip_set_adt_opt *opt)
143 {
144 	const struct hash_netnet4 *h = set->data;
145 	ipset_adtfn adtfn = set->variant->adt[adt];
146 	struct hash_netnet4_elem e = { };
147 	struct ip_set_ext ext = IP_SET_INIT_KEXT(skb, opt, set);
148 
149 	e.cidr[0] = INIT_CIDR(h->nets[0].cidr[0], HOST_MASK);
150 	e.cidr[1] = INIT_CIDR(h->nets[0].cidr[1], HOST_MASK);
151 	if (adt == IPSET_TEST)
152 		e.ccmp = (HOST_MASK << (sizeof(e.cidr[0]) * 8)) | HOST_MASK;
153 
154 	ip4addrptr(skb, opt->flags & IPSET_DIM_ONE_SRC, &e.ip[0]);
155 	ip4addrptr(skb, opt->flags & IPSET_DIM_TWO_SRC, &e.ip[1]);
156 	e.ip[0] &= ip_set_netmask(e.cidr[0]);
157 	e.ip[1] &= ip_set_netmask(e.cidr[1]);
158 
159 	return adtfn(set, &e, &ext, &opt->ext, opt->cmdflags);
160 }
161 
162 static int
163 hash_netnet4_uadt(struct ip_set *set, struct nlattr *tb[],
164 		  enum ipset_adt adt, u32 *lineno, u32 flags, bool retried)
165 {
166 	const struct hash_netnet4 *h = set->data;
167 	ipset_adtfn adtfn = set->variant->adt[adt];
168 	struct hash_netnet4_elem e = { };
169 	struct ip_set_ext ext = IP_SET_INIT_UEXT(set);
170 	u32 ip = 0, ip_to = 0;
171 	u32 ip2 = 0, ip2_from = 0, ip2_to = 0, ipn;
172 	u64 n = 0, m = 0;
173 	int ret;
174 
175 	if (tb[IPSET_ATTR_LINENO])
176 		*lineno = nla_get_u32(tb[IPSET_ATTR_LINENO]);
177 
178 	hash_netnet4_init(&e);
179 	if (unlikely(!tb[IPSET_ATTR_IP] || !tb[IPSET_ATTR_IP2] ||
180 		     !ip_set_optattr_netorder(tb, IPSET_ATTR_CADT_FLAGS)))
181 		return -IPSET_ERR_PROTOCOL;
182 
183 	ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP], &ip);
184 	if (ret)
185 		return ret;
186 
187 	ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP2], &ip2_from);
188 	if (ret)
189 		return ret;
190 
191 	ret = ip_set_get_extensions(set, tb, &ext);
192 	if (ret)
193 		return ret;
194 
195 	if (tb[IPSET_ATTR_CIDR]) {
196 		e.cidr[0] = nla_get_u8(tb[IPSET_ATTR_CIDR]);
197 		if (!e.cidr[0] || e.cidr[0] > HOST_MASK)
198 			return -IPSET_ERR_INVALID_CIDR;
199 	}
200 
201 	if (tb[IPSET_ATTR_CIDR2]) {
202 		e.cidr[1] = nla_get_u8(tb[IPSET_ATTR_CIDR2]);
203 		if (!e.cidr[1] || e.cidr[1] > HOST_MASK)
204 			return -IPSET_ERR_INVALID_CIDR;
205 	}
206 
207 	if (tb[IPSET_ATTR_CADT_FLAGS]) {
208 		u32 cadt_flags = ip_set_get_h32(tb[IPSET_ATTR_CADT_FLAGS]);
209 
210 		if (cadt_flags & IPSET_FLAG_NOMATCH)
211 			flags |= (IPSET_FLAG_NOMATCH << 16);
212 	}
213 
214 	if (adt == IPSET_TEST || !(tb[IPSET_ATTR_IP_TO] ||
215 				   tb[IPSET_ATTR_IP2_TO])) {
216 		e.ip[0] = htonl(ip & ip_set_hostmask(e.cidr[0]));
217 		e.ip[1] = htonl(ip2_from & ip_set_hostmask(e.cidr[1]));
218 		ret = adtfn(set, &e, &ext, &ext, flags);
219 		return ip_set_enomatch(ret, flags, adt, set) ? -ret :
220 		       ip_set_eexist(ret, flags) ? 0 : ret;
221 	}
222 
223 	ip_to = ip;
224 	if (tb[IPSET_ATTR_IP_TO]) {
225 		ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP_TO], &ip_to);
226 		if (ret)
227 			return ret;
228 		if (ip_to < ip)
229 			swap(ip, ip_to);
230 		if (unlikely(ip + UINT_MAX == ip_to))
231 			return -IPSET_ERR_HASH_RANGE;
232 	} else {
233 		ip_set_mask_from_to(ip, ip_to, e.cidr[0]);
234 	}
235 
236 	ip2_to = ip2_from;
237 	if (tb[IPSET_ATTR_IP2_TO]) {
238 		ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP2_TO], &ip2_to);
239 		if (ret)
240 			return ret;
241 		if (ip2_to < ip2_from)
242 			swap(ip2_from, ip2_to);
243 		if (unlikely(ip2_from + UINT_MAX == ip2_to))
244 			return -IPSET_ERR_HASH_RANGE;
245 	} else {
246 		ip_set_mask_from_to(ip2_from, ip2_to, e.cidr[1]);
247 	}
248 	ipn = ip;
249 	do {
250 		ipn = ip_set_range_to_cidr(ipn, ip_to, &e.cidr[0]);
251 		n++;
252 	} while (ipn++ < ip_to);
253 	ipn = ip2_from;
254 	do {
255 		ipn = ip_set_range_to_cidr(ipn, ip2_to, &e.cidr[1]);
256 		m++;
257 	} while (ipn++ < ip2_to);
258 
259 	if (n*m > IPSET_MAX_RANGE)
260 		return -ERANGE;
261 
262 	if (retried) {
263 		ip = ntohl(h->next.ip[0]);
264 		ip2 = ntohl(h->next.ip[1]);
265 	} else {
266 		ip2 = ip2_from;
267 	}
268 
269 	do {
270 		e.ip[0] = htonl(ip);
271 		ip = ip_set_range_to_cidr(ip, ip_to, &e.cidr[0]);
272 		do {
273 			e.ip[1] = htonl(ip2);
274 			ip2 = ip_set_range_to_cidr(ip2, ip2_to, &e.cidr[1]);
275 			ret = adtfn(set, &e, &ext, &ext, flags);
276 			if (ret && !ip_set_eexist(ret, flags))
277 				return ret;
278 
279 			ret = 0;
280 		} while (ip2++ < ip2_to);
281 		ip2 = ip2_from;
282 	} while (ip++ < ip_to);
283 	return ret;
284 }
285 
286 /* IPv6 variants */
287 
288 struct hash_netnet6_elem {
289 	union nf_inet_addr ip[2];
290 	u8 nomatch;
291 	u8 padding;
292 	union {
293 		u8 cidr[2];
294 		u16 ccmp;
295 	};
296 };
297 
298 /* Common functions */
299 
300 static bool
301 hash_netnet6_data_equal(const struct hash_netnet6_elem *ip1,
302 			const struct hash_netnet6_elem *ip2,
303 			u32 *multi)
304 {
305 	return ipv6_addr_equal(&ip1->ip[0].in6, &ip2->ip[0].in6) &&
306 	       ipv6_addr_equal(&ip1->ip[1].in6, &ip2->ip[1].in6) &&
307 	       ip1->ccmp == ip2->ccmp;
308 }
309 
310 static int
311 hash_netnet6_do_data_match(const struct hash_netnet6_elem *elem)
312 {
313 	return elem->nomatch ? -ENOTEMPTY : 1;
314 }
315 
316 static void
317 hash_netnet6_data_set_flags(struct hash_netnet6_elem *elem, u32 flags)
318 {
319 	elem->nomatch = (flags >> 16) & IPSET_FLAG_NOMATCH;
320 }
321 
322 static void
323 hash_netnet6_data_reset_flags(struct hash_netnet6_elem *elem, u8 *flags)
324 {
325 	swap(*flags, elem->nomatch);
326 }
327 
328 static void
329 hash_netnet6_data_reset_elem(struct hash_netnet6_elem *elem,
330 			     struct hash_netnet6_elem *orig)
331 {
332 	elem->ip[1] = orig->ip[1];
333 }
334 
335 static void
336 hash_netnet6_data_netmask(struct hash_netnet6_elem *elem, u8 cidr, bool inner)
337 {
338 	if (inner) {
339 		ip6_netmask(&elem->ip[1], cidr);
340 		elem->cidr[1] = cidr;
341 	} else {
342 		ip6_netmask(&elem->ip[0], cidr);
343 		elem->cidr[0] = cidr;
344 	}
345 }
346 
347 static bool
348 hash_netnet6_data_list(struct sk_buff *skb,
349 		       const struct hash_netnet6_elem *data)
350 {
351 	u32 flags = data->nomatch ? IPSET_FLAG_NOMATCH : 0;
352 
353 	if (nla_put_ipaddr6(skb, IPSET_ATTR_IP, &data->ip[0].in6) ||
354 	    nla_put_ipaddr6(skb, IPSET_ATTR_IP2, &data->ip[1].in6) ||
355 	    nla_put_u8(skb, IPSET_ATTR_CIDR, data->cidr[0]) ||
356 	    nla_put_u8(skb, IPSET_ATTR_CIDR2, data->cidr[1]) ||
357 	    (flags &&
358 	     nla_put_net32(skb, IPSET_ATTR_CADT_FLAGS, htonl(flags))))
359 		goto nla_put_failure;
360 	return false;
361 
362 nla_put_failure:
363 	return true;
364 }
365 
366 static void
367 hash_netnet6_data_next(struct hash_netnet6_elem *next,
368 		       const struct hash_netnet6_elem *d)
369 {
370 }
371 
372 #undef MTYPE
373 #undef HOST_MASK
374 
375 #define MTYPE		hash_netnet6
376 #define HOST_MASK	128
377 #define IP_SET_EMIT_CREATE
378 #include "ip_set_hash_gen.h"
379 
380 static void
381 hash_netnet6_init(struct hash_netnet6_elem *e)
382 {
383 	e->cidr[0] = HOST_MASK;
384 	e->cidr[1] = HOST_MASK;
385 }
386 
387 static int
388 hash_netnet6_kadt(struct ip_set *set, const struct sk_buff *skb,
389 		  const struct xt_action_param *par,
390 		  enum ipset_adt adt, struct ip_set_adt_opt *opt)
391 {
392 	const struct hash_netnet6 *h = set->data;
393 	ipset_adtfn adtfn = set->variant->adt[adt];
394 	struct hash_netnet6_elem e = { };
395 	struct ip_set_ext ext = IP_SET_INIT_KEXT(skb, opt, set);
396 
397 	e.cidr[0] = INIT_CIDR(h->nets[0].cidr[0], HOST_MASK);
398 	e.cidr[1] = INIT_CIDR(h->nets[0].cidr[1], HOST_MASK);
399 	if (adt == IPSET_TEST)
400 		e.ccmp = (HOST_MASK << (sizeof(u8) * 8)) | HOST_MASK;
401 
402 	ip6addrptr(skb, opt->flags & IPSET_DIM_ONE_SRC, &e.ip[0].in6);
403 	ip6addrptr(skb, opt->flags & IPSET_DIM_TWO_SRC, &e.ip[1].in6);
404 	ip6_netmask(&e.ip[0], e.cidr[0]);
405 	ip6_netmask(&e.ip[1], e.cidr[1]);
406 
407 	return adtfn(set, &e, &ext, &opt->ext, opt->cmdflags);
408 }
409 
410 static int
411 hash_netnet6_uadt(struct ip_set *set, struct nlattr *tb[],
412 		  enum ipset_adt adt, u32 *lineno, u32 flags, bool retried)
413 {
414 	ipset_adtfn adtfn = set->variant->adt[adt];
415 	struct hash_netnet6_elem e = { };
416 	struct ip_set_ext ext = IP_SET_INIT_UEXT(set);
417 	int ret;
418 
419 	if (tb[IPSET_ATTR_LINENO])
420 		*lineno = nla_get_u32(tb[IPSET_ATTR_LINENO]);
421 
422 	hash_netnet6_init(&e);
423 	if (unlikely(!tb[IPSET_ATTR_IP] || !tb[IPSET_ATTR_IP2] ||
424 		     !ip_set_optattr_netorder(tb, IPSET_ATTR_CADT_FLAGS)))
425 		return -IPSET_ERR_PROTOCOL;
426 	if (unlikely(tb[IPSET_ATTR_IP_TO] || tb[IPSET_ATTR_IP2_TO]))
427 		return -IPSET_ERR_HASH_RANGE_UNSUPPORTED;
428 
429 	ret = ip_set_get_ipaddr6(tb[IPSET_ATTR_IP], &e.ip[0]);
430 	if (ret)
431 		return ret;
432 
433 	ret = ip_set_get_ipaddr6(tb[IPSET_ATTR_IP2], &e.ip[1]);
434 	if (ret)
435 		return ret;
436 
437 	ret = ip_set_get_extensions(set, tb, &ext);
438 	if (ret)
439 		return ret;
440 
441 	if (tb[IPSET_ATTR_CIDR]) {
442 		e.cidr[0] = nla_get_u8(tb[IPSET_ATTR_CIDR]);
443 		if (!e.cidr[0] || e.cidr[0] > HOST_MASK)
444 			return -IPSET_ERR_INVALID_CIDR;
445 	}
446 
447 	if (tb[IPSET_ATTR_CIDR2]) {
448 		e.cidr[1] = nla_get_u8(tb[IPSET_ATTR_CIDR2]);
449 		if (!e.cidr[1] || e.cidr[1] > HOST_MASK)
450 			return -IPSET_ERR_INVALID_CIDR;
451 	}
452 
453 	ip6_netmask(&e.ip[0], e.cidr[0]);
454 	ip6_netmask(&e.ip[1], e.cidr[1]);
455 
456 	if (tb[IPSET_ATTR_CADT_FLAGS]) {
457 		u32 cadt_flags = ip_set_get_h32(tb[IPSET_ATTR_CADT_FLAGS]);
458 
459 		if (cadt_flags & IPSET_FLAG_NOMATCH)
460 			flags |= (IPSET_FLAG_NOMATCH << 16);
461 	}
462 
463 	ret = adtfn(set, &e, &ext, &ext, flags);
464 
465 	return ip_set_enomatch(ret, flags, adt, set) ? -ret :
466 	       ip_set_eexist(ret, flags) ? 0 : ret;
467 }
468 
469 static struct ip_set_type hash_netnet_type __read_mostly = {
470 	.name		= "hash:net,net",
471 	.protocol	= IPSET_PROTOCOL,
472 	.features	= IPSET_TYPE_IP | IPSET_TYPE_IP2 | IPSET_TYPE_NOMATCH,
473 	.dimension	= IPSET_DIM_TWO,
474 	.family		= NFPROTO_UNSPEC,
475 	.revision_min	= IPSET_TYPE_REV_MIN,
476 	.revision_max	= IPSET_TYPE_REV_MAX,
477 	.create_flags[IPSET_TYPE_REV_MAX] = IPSET_CREATE_FLAG_BUCKETSIZE,
478 	.create		= hash_netnet_create,
479 	.create_policy	= {
480 		[IPSET_ATTR_HASHSIZE]	= { .type = NLA_U32 },
481 		[IPSET_ATTR_MAXELEM]	= { .type = NLA_U32 },
482 		[IPSET_ATTR_INITVAL]	= { .type = NLA_U32 },
483 		[IPSET_ATTR_BUCKETSIZE]	= { .type = NLA_U8 },
484 		[IPSET_ATTR_RESIZE]	= { .type = NLA_U8  },
485 		[IPSET_ATTR_TIMEOUT]	= { .type = NLA_U32 },
486 		[IPSET_ATTR_CADT_FLAGS]	= { .type = NLA_U32 },
487 	},
488 	.adt_policy	= {
489 		[IPSET_ATTR_IP]		= { .type = NLA_NESTED },
490 		[IPSET_ATTR_IP_TO]	= { .type = NLA_NESTED },
491 		[IPSET_ATTR_IP2]	= { .type = NLA_NESTED },
492 		[IPSET_ATTR_IP2_TO]	= { .type = NLA_NESTED },
493 		[IPSET_ATTR_CIDR]	= { .type = NLA_U8 },
494 		[IPSET_ATTR_CIDR2]	= { .type = NLA_U8 },
495 		[IPSET_ATTR_TIMEOUT]	= { .type = NLA_U32 },
496 		[IPSET_ATTR_LINENO]	= { .type = NLA_U32 },
497 		[IPSET_ATTR_CADT_FLAGS]	= { .type = NLA_U32 },
498 		[IPSET_ATTR_BYTES]	= { .type = NLA_U64 },
499 		[IPSET_ATTR_PACKETS]	= { .type = NLA_U64 },
500 		[IPSET_ATTR_COMMENT]	= { .type = NLA_NUL_STRING,
501 					    .len  = IPSET_MAX_COMMENT_SIZE },
502 		[IPSET_ATTR_SKBMARK]	= { .type = NLA_U64 },
503 		[IPSET_ATTR_SKBPRIO]	= { .type = NLA_U32 },
504 		[IPSET_ATTR_SKBQUEUE]	= { .type = NLA_U16 },
505 	},
506 	.me		= THIS_MODULE,
507 };
508 
509 static int __init
510 hash_netnet_init(void)
511 {
512 	return ip_set_type_register(&hash_netnet_type);
513 }
514 
515 static void __exit
516 hash_netnet_fini(void)
517 {
518 	rcu_barrier();
519 	ip_set_type_unregister(&hash_netnet_type);
520 }
521 
522 module_init(hash_netnet_init);
523 module_exit(hash_netnet_fini);
524