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 /*				3	   bucketsize, initval support added */
27 #define IPSET_TYPE_REV_MAX	4	/* bitmask support added */
28 
29 MODULE_LICENSE("GPL");
30 MODULE_AUTHOR("Oliver Smith <oliver@8.c.9.b.0.7.4.0.1.0.0.2.ip6.arpa>");
31 IP_SET_MODULE_DESC("hash:net,net", IPSET_TYPE_REV_MIN, IPSET_TYPE_REV_MAX);
32 MODULE_ALIAS("ip_set_hash:net,net");
33 
34 /* Type specific function prefix */
35 #define HTYPE		hash_netnet
36 #define IP_SET_HASH_WITH_NETS
37 #define IP_SET_HASH_WITH_NETMASK
38 #define IP_SET_HASH_WITH_BITMASK
39 #define IPSET_NET_COUNT 2
40 
41 /* IPv4 variants */
42 
43 /* Member elements  */
44 struct hash_netnet4_elem {
45 	union {
46 		__be32 ip[2];
47 		__be64 ipcmp;
48 	};
49 	u8 nomatch;
50 	u8 padding;
51 	union {
52 		u8 cidr[2];
53 		u16 ccmp;
54 	};
55 };
56 
57 /* Common functions */
58 
59 static bool
60 hash_netnet4_data_equal(const struct hash_netnet4_elem *ip1,
61 			const struct hash_netnet4_elem *ip2,
62 			u32 *multi)
63 {
64 	return ip1->ipcmp == ip2->ipcmp &&
65 	       ip1->ccmp == ip2->ccmp;
66 }
67 
68 static int
69 hash_netnet4_do_data_match(const struct hash_netnet4_elem *elem)
70 {
71 	return elem->nomatch ? -ENOTEMPTY : 1;
72 }
73 
74 static void
75 hash_netnet4_data_set_flags(struct hash_netnet4_elem *elem, u32 flags)
76 {
77 	elem->nomatch = (flags >> 16) & IPSET_FLAG_NOMATCH;
78 }
79 
80 static void
81 hash_netnet4_data_reset_flags(struct hash_netnet4_elem *elem, u8 *flags)
82 {
83 	swap(*flags, elem->nomatch);
84 }
85 
86 static void
87 hash_netnet4_data_reset_elem(struct hash_netnet4_elem *elem,
88 			     struct hash_netnet4_elem *orig)
89 {
90 	elem->ip[1] = orig->ip[1];
91 }
92 
93 static void
94 hash_netnet4_data_netmask(struct hash_netnet4_elem *elem, u8 cidr, bool inner)
95 {
96 	if (inner) {
97 		elem->ip[1] &= ip_set_netmask(cidr);
98 		elem->cidr[1] = cidr;
99 	} else {
100 		elem->ip[0] &= ip_set_netmask(cidr);
101 		elem->cidr[0] = cidr;
102 	}
103 }
104 
105 static bool
106 hash_netnet4_data_list(struct sk_buff *skb,
107 		       const struct hash_netnet4_elem *data)
108 {
109 	u32 flags = data->nomatch ? IPSET_FLAG_NOMATCH : 0;
110 
111 	if (nla_put_ipaddr4(skb, IPSET_ATTR_IP, data->ip[0]) ||
112 	    nla_put_ipaddr4(skb, IPSET_ATTR_IP2, data->ip[1]) ||
113 	    nla_put_u8(skb, IPSET_ATTR_CIDR, data->cidr[0]) ||
114 	    nla_put_u8(skb, IPSET_ATTR_CIDR2, data->cidr[1]) ||
115 	    (flags &&
116 	     nla_put_net32(skb, IPSET_ATTR_CADT_FLAGS, htonl(flags))))
117 		goto nla_put_failure;
118 	return false;
119 
120 nla_put_failure:
121 	return true;
122 }
123 
124 static void
125 hash_netnet4_data_next(struct hash_netnet4_elem *next,
126 		       const struct hash_netnet4_elem *d)
127 {
128 	next->ipcmp = d->ipcmp;
129 }
130 
131 #define MTYPE		hash_netnet4
132 #define HOST_MASK	32
133 #include "ip_set_hash_gen.h"
134 
135 static void
136 hash_netnet4_init(struct hash_netnet4_elem *e)
137 {
138 	e->cidr[0] = HOST_MASK;
139 	e->cidr[1] = HOST_MASK;
140 }
141 
142 static int
143 hash_netnet4_kadt(struct ip_set *set, const struct sk_buff *skb,
144 		  const struct xt_action_param *par,
145 		  enum ipset_adt adt, struct ip_set_adt_opt *opt)
146 {
147 	const struct hash_netnet4 *h = set->data;
148 	ipset_adtfn adtfn = set->variant->adt[adt];
149 	struct hash_netnet4_elem e = { };
150 	struct ip_set_ext ext = IP_SET_INIT_KEXT(skb, opt, set);
151 
152 	e.cidr[0] = INIT_CIDR(h->nets[0].cidr[0], HOST_MASK);
153 	e.cidr[1] = INIT_CIDR(h->nets[0].cidr[1], HOST_MASK);
154 	if (adt == IPSET_TEST)
155 		e.ccmp = (HOST_MASK << (sizeof(e.cidr[0]) * 8)) | HOST_MASK;
156 
157 	ip4addrptr(skb, opt->flags & IPSET_DIM_ONE_SRC, &e.ip[0]);
158 	ip4addrptr(skb, opt->flags & IPSET_DIM_TWO_SRC, &e.ip[1]);
159 	e.ip[0] &= (ip_set_netmask(e.cidr[0]) & h->bitmask.ip);
160 	e.ip[1] &= (ip_set_netmask(e.cidr[1]) & h->bitmask.ip);
161 
162 	return adtfn(set, &e, &ext, &opt->ext, opt->cmdflags);
163 }
164 
165 static int
166 hash_netnet4_uadt(struct ip_set *set, struct nlattr *tb[],
167 		  enum ipset_adt adt, u32 *lineno, u32 flags, bool retried)
168 {
169 	struct hash_netnet4 *h = set->data;
170 	ipset_adtfn adtfn = set->variant->adt[adt];
171 	struct hash_netnet4_elem e = { };
172 	struct ip_set_ext ext = IP_SET_INIT_UEXT(set);
173 	u32 ip = 0, ip_to = 0;
174 	u32 ip2 = 0, ip2_from = 0, ip2_to = 0, i = 0;
175 	int ret;
176 
177 	if (tb[IPSET_ATTR_LINENO])
178 		*lineno = nla_get_u32(tb[IPSET_ATTR_LINENO]);
179 
180 	hash_netnet4_init(&e);
181 	if (unlikely(!tb[IPSET_ATTR_IP] || !tb[IPSET_ATTR_IP2] ||
182 		     !ip_set_optattr_netorder(tb, IPSET_ATTR_CADT_FLAGS)))
183 		return -IPSET_ERR_PROTOCOL;
184 
185 	ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP], &ip);
186 	if (ret)
187 		return ret;
188 
189 	ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP2], &ip2_from);
190 	if (ret)
191 		return ret;
192 
193 	ret = ip_set_get_extensions(set, tb, &ext);
194 	if (ret)
195 		return ret;
196 
197 	if (tb[IPSET_ATTR_CIDR]) {
198 		e.cidr[0] = nla_get_u8(tb[IPSET_ATTR_CIDR]);
199 		if (!e.cidr[0] || e.cidr[0] > HOST_MASK)
200 			return -IPSET_ERR_INVALID_CIDR;
201 	}
202 
203 	if (tb[IPSET_ATTR_CIDR2]) {
204 		e.cidr[1] = nla_get_u8(tb[IPSET_ATTR_CIDR2]);
205 		if (!e.cidr[1] || e.cidr[1] > HOST_MASK)
206 			return -IPSET_ERR_INVALID_CIDR;
207 	}
208 
209 	if (tb[IPSET_ATTR_CADT_FLAGS]) {
210 		u32 cadt_flags = ip_set_get_h32(tb[IPSET_ATTR_CADT_FLAGS]);
211 
212 		if (cadt_flags & IPSET_FLAG_NOMATCH)
213 			flags |= (IPSET_FLAG_NOMATCH << 16);
214 	}
215 
216 	if (adt == IPSET_TEST || !(tb[IPSET_ATTR_IP_TO] ||
217 				   tb[IPSET_ATTR_IP2_TO])) {
218 		e.ip[0] = htonl(ip & ntohl(h->bitmask.ip) & ip_set_hostmask(e.cidr[0]));
219 		e.ip[1] = htonl(ip2_from & ntohl(h->bitmask.ip) & ip_set_hostmask(e.cidr[1]));
220 		ret = adtfn(set, &e, &ext, &ext, flags);
221 		return ip_set_enomatch(ret, flags, adt, set) ? -ret :
222 		       ip_set_eexist(ret, flags) ? 0 : ret;
223 	}
224 
225 	ip_to = ip;
226 	if (tb[IPSET_ATTR_IP_TO]) {
227 		ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP_TO], &ip_to);
228 		if (ret)
229 			return ret;
230 		if (ip_to < ip)
231 			swap(ip, ip_to);
232 		if (unlikely(ip + UINT_MAX == ip_to))
233 			return -IPSET_ERR_HASH_RANGE;
234 	} else {
235 		ip_set_mask_from_to(ip, ip_to, e.cidr[0]);
236 	}
237 
238 	ip2_to = ip2_from;
239 	if (tb[IPSET_ATTR_IP2_TO]) {
240 		ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP2_TO], &ip2_to);
241 		if (ret)
242 			return ret;
243 		if (ip2_to < ip2_from)
244 			swap(ip2_from, ip2_to);
245 		if (unlikely(ip2_from + UINT_MAX == ip2_to))
246 			return -IPSET_ERR_HASH_RANGE;
247 	} else {
248 		ip_set_mask_from_to(ip2_from, ip2_to, e.cidr[1]);
249 	}
250 
251 	if (retried) {
252 		ip = ntohl(h->next.ip[0]);
253 		ip2 = ntohl(h->next.ip[1]);
254 	} else {
255 		ip2 = ip2_from;
256 	}
257 
258 	do {
259 		e.ip[0] = htonl(ip);
260 		ip = ip_set_range_to_cidr(ip, ip_to, &e.cidr[0]);
261 		do {
262 			i++;
263 			e.ip[1] = htonl(ip2);
264 			if (i > IPSET_MAX_RANGE) {
265 				hash_netnet4_data_next(&h->next, &e);
266 				return -ERANGE;
267 			}
268 			ip2 = ip_set_range_to_cidr(ip2, ip2_to, &e.cidr[1]);
269 			ret = adtfn(set, &e, &ext, &ext, flags);
270 			if (ret && !ip_set_eexist(ret, flags))
271 				return ret;
272 
273 			ret = 0;
274 		} while (ip2++ < ip2_to);
275 		ip2 = ip2_from;
276 	} while (ip++ < ip_to);
277 	return ret;
278 }
279 
280 /* IPv6 variants */
281 
282 struct hash_netnet6_elem {
283 	union nf_inet_addr ip[2];
284 	u8 nomatch;
285 	u8 padding;
286 	union {
287 		u8 cidr[2];
288 		u16 ccmp;
289 	};
290 };
291 
292 /* Common functions */
293 
294 static bool
295 hash_netnet6_data_equal(const struct hash_netnet6_elem *ip1,
296 			const struct hash_netnet6_elem *ip2,
297 			u32 *multi)
298 {
299 	return ipv6_addr_equal(&ip1->ip[0].in6, &ip2->ip[0].in6) &&
300 	       ipv6_addr_equal(&ip1->ip[1].in6, &ip2->ip[1].in6) &&
301 	       ip1->ccmp == ip2->ccmp;
302 }
303 
304 static int
305 hash_netnet6_do_data_match(const struct hash_netnet6_elem *elem)
306 {
307 	return elem->nomatch ? -ENOTEMPTY : 1;
308 }
309 
310 static void
311 hash_netnet6_data_set_flags(struct hash_netnet6_elem *elem, u32 flags)
312 {
313 	elem->nomatch = (flags >> 16) & IPSET_FLAG_NOMATCH;
314 }
315 
316 static void
317 hash_netnet6_data_reset_flags(struct hash_netnet6_elem *elem, u8 *flags)
318 {
319 	swap(*flags, elem->nomatch);
320 }
321 
322 static void
323 hash_netnet6_data_reset_elem(struct hash_netnet6_elem *elem,
324 			     struct hash_netnet6_elem *orig)
325 {
326 	elem->ip[1] = orig->ip[1];
327 }
328 
329 static void
330 hash_netnet6_data_netmask(struct hash_netnet6_elem *elem, u8 cidr, bool inner)
331 {
332 	if (inner) {
333 		ip6_netmask(&elem->ip[1], cidr);
334 		elem->cidr[1] = cidr;
335 	} else {
336 		ip6_netmask(&elem->ip[0], cidr);
337 		elem->cidr[0] = cidr;
338 	}
339 }
340 
341 static bool
342 hash_netnet6_data_list(struct sk_buff *skb,
343 		       const struct hash_netnet6_elem *data)
344 {
345 	u32 flags = data->nomatch ? IPSET_FLAG_NOMATCH : 0;
346 
347 	if (nla_put_ipaddr6(skb, IPSET_ATTR_IP, &data->ip[0].in6) ||
348 	    nla_put_ipaddr6(skb, IPSET_ATTR_IP2, &data->ip[1].in6) ||
349 	    nla_put_u8(skb, IPSET_ATTR_CIDR, data->cidr[0]) ||
350 	    nla_put_u8(skb, IPSET_ATTR_CIDR2, data->cidr[1]) ||
351 	    (flags &&
352 	     nla_put_net32(skb, IPSET_ATTR_CADT_FLAGS, htonl(flags))))
353 		goto nla_put_failure;
354 	return false;
355 
356 nla_put_failure:
357 	return true;
358 }
359 
360 static void
361 hash_netnet6_data_next(struct hash_netnet6_elem *next,
362 		       const struct hash_netnet6_elem *d)
363 {
364 }
365 
366 #undef MTYPE
367 #undef HOST_MASK
368 
369 #define MTYPE		hash_netnet6
370 #define HOST_MASK	128
371 #define IP_SET_EMIT_CREATE
372 #include "ip_set_hash_gen.h"
373 
374 static void
375 hash_netnet6_init(struct hash_netnet6_elem *e)
376 {
377 	e->cidr[0] = HOST_MASK;
378 	e->cidr[1] = HOST_MASK;
379 }
380 
381 static int
382 hash_netnet6_kadt(struct ip_set *set, const struct sk_buff *skb,
383 		  const struct xt_action_param *par,
384 		  enum ipset_adt adt, struct ip_set_adt_opt *opt)
385 {
386 	const struct hash_netnet6 *h = set->data;
387 	ipset_adtfn adtfn = set->variant->adt[adt];
388 	struct hash_netnet6_elem e = { };
389 	struct ip_set_ext ext = IP_SET_INIT_KEXT(skb, opt, set);
390 
391 	e.cidr[0] = INIT_CIDR(h->nets[0].cidr[0], HOST_MASK);
392 	e.cidr[1] = INIT_CIDR(h->nets[0].cidr[1], HOST_MASK);
393 	if (adt == IPSET_TEST)
394 		e.ccmp = (HOST_MASK << (sizeof(u8) * 8)) | HOST_MASK;
395 
396 	ip6addrptr(skb, opt->flags & IPSET_DIM_ONE_SRC, &e.ip[0].in6);
397 	ip6addrptr(skb, opt->flags & IPSET_DIM_TWO_SRC, &e.ip[1].in6);
398 	ip6_netmask(&e.ip[0], e.cidr[0]);
399 	ip6_netmask(&e.ip[1], e.cidr[1]);
400 
401 	nf_inet_addr_mask_inplace(&e.ip[0], &h->bitmask);
402 	nf_inet_addr_mask_inplace(&e.ip[1], &h->bitmask);
403 	if (e.cidr[0] == HOST_MASK && ipv6_addr_any(&e.ip[0].in6))
404 		return -EINVAL;
405 
406 	return adtfn(set, &e, &ext, &opt->ext, opt->cmdflags);
407 }
408 
409 static int
410 hash_netnet6_uadt(struct ip_set *set, struct nlattr *tb[],
411 		  enum ipset_adt adt, u32 *lineno, u32 flags, bool retried)
412 {
413 	ipset_adtfn adtfn = set->variant->adt[adt];
414 	struct hash_netnet6_elem e = { };
415 	struct ip_set_ext ext = IP_SET_INIT_UEXT(set);
416 	const struct hash_netnet6 *h = set->data;
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 	nf_inet_addr_mask_inplace(&e.ip[0], &h->bitmask);
457 	nf_inet_addr_mask_inplace(&e.ip[1], &h->bitmask);
458 	if (e.cidr[0] == HOST_MASK && ipv6_addr_any(&e.ip[0].in6))
459 		return -IPSET_ERR_HASH_ELEM;
460 
461 	if (tb[IPSET_ATTR_CADT_FLAGS]) {
462 		u32 cadt_flags = ip_set_get_h32(tb[IPSET_ATTR_CADT_FLAGS]);
463 
464 		if (cadt_flags & IPSET_FLAG_NOMATCH)
465 			flags |= (IPSET_FLAG_NOMATCH << 16);
466 	}
467 
468 	ret = adtfn(set, &e, &ext, &ext, flags);
469 
470 	return ip_set_enomatch(ret, flags, adt, set) ? -ret :
471 	       ip_set_eexist(ret, flags) ? 0 : ret;
472 }
473 
474 static struct ip_set_type hash_netnet_type __read_mostly = {
475 	.name		= "hash:net,net",
476 	.protocol	= IPSET_PROTOCOL,
477 	.features	= IPSET_TYPE_IP | IPSET_TYPE_IP2 | IPSET_TYPE_NOMATCH,
478 	.dimension	= IPSET_DIM_TWO,
479 	.family		= NFPROTO_UNSPEC,
480 	.revision_min	= IPSET_TYPE_REV_MIN,
481 	.revision_max	= IPSET_TYPE_REV_MAX,
482 	.create_flags[IPSET_TYPE_REV_MAX] = IPSET_CREATE_FLAG_BUCKETSIZE,
483 	.create		= hash_netnet_create,
484 	.create_policy	= {
485 		[IPSET_ATTR_HASHSIZE]	= { .type = NLA_U32 },
486 		[IPSET_ATTR_MAXELEM]	= { .type = NLA_U32 },
487 		[IPSET_ATTR_INITVAL]	= { .type = NLA_U32 },
488 		[IPSET_ATTR_BUCKETSIZE]	= { .type = NLA_U8 },
489 		[IPSET_ATTR_RESIZE]	= { .type = NLA_U8  },
490 		[IPSET_ATTR_TIMEOUT]	= { .type = NLA_U32 },
491 		[IPSET_ATTR_CADT_FLAGS]	= { .type = NLA_U32 },
492 		[IPSET_ATTR_NETMASK]    = { .type = NLA_U8 },
493 		[IPSET_ATTR_BITMASK]	= { .type = NLA_NESTED },
494 	},
495 	.adt_policy	= {
496 		[IPSET_ATTR_IP]		= { .type = NLA_NESTED },
497 		[IPSET_ATTR_IP_TO]	= { .type = NLA_NESTED },
498 		[IPSET_ATTR_IP2]	= { .type = NLA_NESTED },
499 		[IPSET_ATTR_IP2_TO]	= { .type = NLA_NESTED },
500 		[IPSET_ATTR_CIDR]	= { .type = NLA_U8 },
501 		[IPSET_ATTR_CIDR2]	= { .type = NLA_U8 },
502 		[IPSET_ATTR_TIMEOUT]	= { .type = NLA_U32 },
503 		[IPSET_ATTR_LINENO]	= { .type = NLA_U32 },
504 		[IPSET_ATTR_CADT_FLAGS]	= { .type = NLA_U32 },
505 		[IPSET_ATTR_BYTES]	= { .type = NLA_U64 },
506 		[IPSET_ATTR_PACKETS]	= { .type = NLA_U64 },
507 		[IPSET_ATTR_COMMENT]	= { .type = NLA_NUL_STRING,
508 					    .len  = IPSET_MAX_COMMENT_SIZE },
509 		[IPSET_ATTR_SKBMARK]	= { .type = NLA_U64 },
510 		[IPSET_ATTR_SKBPRIO]	= { .type = NLA_U32 },
511 		[IPSET_ATTR_SKBQUEUE]	= { .type = NLA_U16 },
512 	},
513 	.me		= THIS_MODULE,
514 };
515 
516 static int __init
517 hash_netnet_init(void)
518 {
519 	return ip_set_type_register(&hash_netnet_type);
520 }
521 
522 static void __exit
523 hash_netnet_fini(void)
524 {
525 	rcu_barrier();
526 	ip_set_type_unregister(&hash_netnet_type);
527 }
528 
529 module_init(hash_netnet_init);
530 module_exit(hash_netnet_fini);
531