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;
172 	int ret;
173 
174 	if (tb[IPSET_ATTR_LINENO])
175 		*lineno = nla_get_u32(tb[IPSET_ATTR_LINENO]);
176 
177 	hash_netnet4_init(&e);
178 	if (unlikely(!tb[IPSET_ATTR_IP] || !tb[IPSET_ATTR_IP2] ||
179 		     !ip_set_optattr_netorder(tb, IPSET_ATTR_CADT_FLAGS)))
180 		return -IPSET_ERR_PROTOCOL;
181 
182 	ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP], &ip);
183 	if (ret)
184 		return ret;
185 
186 	ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP2], &ip2_from);
187 	if (ret)
188 		return ret;
189 
190 	ret = ip_set_get_extensions(set, tb, &ext);
191 	if (ret)
192 		return ret;
193 
194 	if (tb[IPSET_ATTR_CIDR]) {
195 		e.cidr[0] = nla_get_u8(tb[IPSET_ATTR_CIDR]);
196 		if (!e.cidr[0] || e.cidr[0] > HOST_MASK)
197 			return -IPSET_ERR_INVALID_CIDR;
198 	}
199 
200 	if (tb[IPSET_ATTR_CIDR2]) {
201 		e.cidr[1] = nla_get_u8(tb[IPSET_ATTR_CIDR2]);
202 		if (!e.cidr[1] || e.cidr[1] > HOST_MASK)
203 			return -IPSET_ERR_INVALID_CIDR;
204 	}
205 
206 	if (tb[IPSET_ATTR_CADT_FLAGS]) {
207 		u32 cadt_flags = ip_set_get_h32(tb[IPSET_ATTR_CADT_FLAGS]);
208 
209 		if (cadt_flags & IPSET_FLAG_NOMATCH)
210 			flags |= (IPSET_FLAG_NOMATCH << 16);
211 	}
212 
213 	if (adt == IPSET_TEST || !(tb[IPSET_ATTR_IP_TO] ||
214 				   tb[IPSET_ATTR_IP2_TO])) {
215 		e.ip[0] = htonl(ip & ip_set_hostmask(e.cidr[0]));
216 		e.ip[1] = htonl(ip2_from & ip_set_hostmask(e.cidr[1]));
217 		ret = adtfn(set, &e, &ext, &ext, flags);
218 		return ip_set_enomatch(ret, flags, adt, set) ? -ret :
219 		       ip_set_eexist(ret, flags) ? 0 : ret;
220 	}
221 
222 	ip_to = ip;
223 	if (tb[IPSET_ATTR_IP_TO]) {
224 		ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP_TO], &ip_to);
225 		if (ret)
226 			return ret;
227 		if (ip_to < ip)
228 			swap(ip, ip_to);
229 		if (unlikely(ip + UINT_MAX == ip_to))
230 			return -IPSET_ERR_HASH_RANGE;
231 	} else {
232 		ip_set_mask_from_to(ip, ip_to, e.cidr[0]);
233 	}
234 
235 	ip2_to = ip2_from;
236 	if (tb[IPSET_ATTR_IP2_TO]) {
237 		ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP2_TO], &ip2_to);
238 		if (ret)
239 			return ret;
240 		if (ip2_to < ip2_from)
241 			swap(ip2_from, ip2_to);
242 		if (unlikely(ip2_from + UINT_MAX == ip2_to))
243 			return -IPSET_ERR_HASH_RANGE;
244 	} else {
245 		ip_set_mask_from_to(ip2_from, ip2_to, e.cidr[1]);
246 	}
247 
248 	if (retried) {
249 		ip = ntohl(h->next.ip[0]);
250 		ip2 = ntohl(h->next.ip[1]);
251 	} else {
252 		ip2 = ip2_from;
253 	}
254 
255 	do {
256 		e.ip[0] = htonl(ip);
257 		ip = ip_set_range_to_cidr(ip, ip_to, &e.cidr[0]);
258 		do {
259 			e.ip[1] = htonl(ip2);
260 			ip2 = ip_set_range_to_cidr(ip2, ip2_to, &e.cidr[1]);
261 			ret = adtfn(set, &e, &ext, &ext, flags);
262 			if (ret && !ip_set_eexist(ret, flags))
263 				return ret;
264 
265 			ret = 0;
266 		} while (ip2++ < ip2_to);
267 		ip2 = ip2_from;
268 	} while (ip++ < ip_to);
269 	return ret;
270 }
271 
272 /* IPv6 variants */
273 
274 struct hash_netnet6_elem {
275 	union nf_inet_addr ip[2];
276 	u8 nomatch;
277 	u8 padding;
278 	union {
279 		u8 cidr[2];
280 		u16 ccmp;
281 	};
282 };
283 
284 /* Common functions */
285 
286 static bool
287 hash_netnet6_data_equal(const struct hash_netnet6_elem *ip1,
288 			const struct hash_netnet6_elem *ip2,
289 			u32 *multi)
290 {
291 	return ipv6_addr_equal(&ip1->ip[0].in6, &ip2->ip[0].in6) &&
292 	       ipv6_addr_equal(&ip1->ip[1].in6, &ip2->ip[1].in6) &&
293 	       ip1->ccmp == ip2->ccmp;
294 }
295 
296 static int
297 hash_netnet6_do_data_match(const struct hash_netnet6_elem *elem)
298 {
299 	return elem->nomatch ? -ENOTEMPTY : 1;
300 }
301 
302 static void
303 hash_netnet6_data_set_flags(struct hash_netnet6_elem *elem, u32 flags)
304 {
305 	elem->nomatch = (flags >> 16) & IPSET_FLAG_NOMATCH;
306 }
307 
308 static void
309 hash_netnet6_data_reset_flags(struct hash_netnet6_elem *elem, u8 *flags)
310 {
311 	swap(*flags, elem->nomatch);
312 }
313 
314 static void
315 hash_netnet6_data_reset_elem(struct hash_netnet6_elem *elem,
316 			     struct hash_netnet6_elem *orig)
317 {
318 	elem->ip[1] = orig->ip[1];
319 }
320 
321 static void
322 hash_netnet6_data_netmask(struct hash_netnet6_elem *elem, u8 cidr, bool inner)
323 {
324 	if (inner) {
325 		ip6_netmask(&elem->ip[1], cidr);
326 		elem->cidr[1] = cidr;
327 	} else {
328 		ip6_netmask(&elem->ip[0], cidr);
329 		elem->cidr[0] = cidr;
330 	}
331 }
332 
333 static bool
334 hash_netnet6_data_list(struct sk_buff *skb,
335 		       const struct hash_netnet6_elem *data)
336 {
337 	u32 flags = data->nomatch ? IPSET_FLAG_NOMATCH : 0;
338 
339 	if (nla_put_ipaddr6(skb, IPSET_ATTR_IP, &data->ip[0].in6) ||
340 	    nla_put_ipaddr6(skb, IPSET_ATTR_IP2, &data->ip[1].in6) ||
341 	    nla_put_u8(skb, IPSET_ATTR_CIDR, data->cidr[0]) ||
342 	    nla_put_u8(skb, IPSET_ATTR_CIDR2, data->cidr[1]) ||
343 	    (flags &&
344 	     nla_put_net32(skb, IPSET_ATTR_CADT_FLAGS, htonl(flags))))
345 		goto nla_put_failure;
346 	return false;
347 
348 nla_put_failure:
349 	return true;
350 }
351 
352 static void
353 hash_netnet6_data_next(struct hash_netnet6_elem *next,
354 		       const struct hash_netnet6_elem *d)
355 {
356 }
357 
358 #undef MTYPE
359 #undef HOST_MASK
360 
361 #define MTYPE		hash_netnet6
362 #define HOST_MASK	128
363 #define IP_SET_EMIT_CREATE
364 #include "ip_set_hash_gen.h"
365 
366 static void
367 hash_netnet6_init(struct hash_netnet6_elem *e)
368 {
369 	e->cidr[0] = HOST_MASK;
370 	e->cidr[1] = HOST_MASK;
371 }
372 
373 static int
374 hash_netnet6_kadt(struct ip_set *set, const struct sk_buff *skb,
375 		  const struct xt_action_param *par,
376 		  enum ipset_adt adt, struct ip_set_adt_opt *opt)
377 {
378 	const struct hash_netnet6 *h = set->data;
379 	ipset_adtfn adtfn = set->variant->adt[adt];
380 	struct hash_netnet6_elem e = { };
381 	struct ip_set_ext ext = IP_SET_INIT_KEXT(skb, opt, set);
382 
383 	e.cidr[0] = INIT_CIDR(h->nets[0].cidr[0], HOST_MASK);
384 	e.cidr[1] = INIT_CIDR(h->nets[0].cidr[1], HOST_MASK);
385 	if (adt == IPSET_TEST)
386 		e.ccmp = (HOST_MASK << (sizeof(u8) * 8)) | HOST_MASK;
387 
388 	ip6addrptr(skb, opt->flags & IPSET_DIM_ONE_SRC, &e.ip[0].in6);
389 	ip6addrptr(skb, opt->flags & IPSET_DIM_TWO_SRC, &e.ip[1].in6);
390 	ip6_netmask(&e.ip[0], e.cidr[0]);
391 	ip6_netmask(&e.ip[1], e.cidr[1]);
392 
393 	return adtfn(set, &e, &ext, &opt->ext, opt->cmdflags);
394 }
395 
396 static int
397 hash_netnet6_uadt(struct ip_set *set, struct nlattr *tb[],
398 		  enum ipset_adt adt, u32 *lineno, u32 flags, bool retried)
399 {
400 	ipset_adtfn adtfn = set->variant->adt[adt];
401 	struct hash_netnet6_elem e = { };
402 	struct ip_set_ext ext = IP_SET_INIT_UEXT(set);
403 	int ret;
404 
405 	if (tb[IPSET_ATTR_LINENO])
406 		*lineno = nla_get_u32(tb[IPSET_ATTR_LINENO]);
407 
408 	hash_netnet6_init(&e);
409 	if (unlikely(!tb[IPSET_ATTR_IP] || !tb[IPSET_ATTR_IP2] ||
410 		     !ip_set_optattr_netorder(tb, IPSET_ATTR_CADT_FLAGS)))
411 		return -IPSET_ERR_PROTOCOL;
412 	if (unlikely(tb[IPSET_ATTR_IP_TO] || tb[IPSET_ATTR_IP2_TO]))
413 		return -IPSET_ERR_HASH_RANGE_UNSUPPORTED;
414 
415 	ret = ip_set_get_ipaddr6(tb[IPSET_ATTR_IP], &e.ip[0]);
416 	if (ret)
417 		return ret;
418 
419 	ret = ip_set_get_ipaddr6(tb[IPSET_ATTR_IP2], &e.ip[1]);
420 	if (ret)
421 		return ret;
422 
423 	ret = ip_set_get_extensions(set, tb, &ext);
424 	if (ret)
425 		return ret;
426 
427 	if (tb[IPSET_ATTR_CIDR]) {
428 		e.cidr[0] = nla_get_u8(tb[IPSET_ATTR_CIDR]);
429 		if (!e.cidr[0] || e.cidr[0] > HOST_MASK)
430 			return -IPSET_ERR_INVALID_CIDR;
431 	}
432 
433 	if (tb[IPSET_ATTR_CIDR2]) {
434 		e.cidr[1] = nla_get_u8(tb[IPSET_ATTR_CIDR2]);
435 		if (!e.cidr[1] || e.cidr[1] > HOST_MASK)
436 			return -IPSET_ERR_INVALID_CIDR;
437 	}
438 
439 	ip6_netmask(&e.ip[0], e.cidr[0]);
440 	ip6_netmask(&e.ip[1], e.cidr[1]);
441 
442 	if (tb[IPSET_ATTR_CADT_FLAGS]) {
443 		u32 cadt_flags = ip_set_get_h32(tb[IPSET_ATTR_CADT_FLAGS]);
444 
445 		if (cadt_flags & IPSET_FLAG_NOMATCH)
446 			flags |= (IPSET_FLAG_NOMATCH << 16);
447 	}
448 
449 	ret = adtfn(set, &e, &ext, &ext, flags);
450 
451 	return ip_set_enomatch(ret, flags, adt, set) ? -ret :
452 	       ip_set_eexist(ret, flags) ? 0 : ret;
453 }
454 
455 static struct ip_set_type hash_netnet_type __read_mostly = {
456 	.name		= "hash:net,net",
457 	.protocol	= IPSET_PROTOCOL,
458 	.features	= IPSET_TYPE_IP | IPSET_TYPE_IP2 | IPSET_TYPE_NOMATCH,
459 	.dimension	= IPSET_DIM_TWO,
460 	.family		= NFPROTO_UNSPEC,
461 	.revision_min	= IPSET_TYPE_REV_MIN,
462 	.revision_max	= IPSET_TYPE_REV_MAX,
463 	.create_flags[IPSET_TYPE_REV_MAX] = IPSET_CREATE_FLAG_BUCKETSIZE,
464 	.create		= hash_netnet_create,
465 	.create_policy	= {
466 		[IPSET_ATTR_HASHSIZE]	= { .type = NLA_U32 },
467 		[IPSET_ATTR_MAXELEM]	= { .type = NLA_U32 },
468 		[IPSET_ATTR_INITVAL]	= { .type = NLA_U32 },
469 		[IPSET_ATTR_BUCKETSIZE]	= { .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_LINENO]	= { .type = NLA_U32 },
483 		[IPSET_ATTR_CADT_FLAGS]	= { .type = NLA_U32 },
484 		[IPSET_ATTR_BYTES]	= { .type = NLA_U64 },
485 		[IPSET_ATTR_PACKETS]	= { .type = NLA_U64 },
486 		[IPSET_ATTR_COMMENT]	= { .type = NLA_NUL_STRING,
487 					    .len  = IPSET_MAX_COMMENT_SIZE },
488 		[IPSET_ATTR_SKBMARK]	= { .type = NLA_U64 },
489 		[IPSET_ATTR_SKBPRIO]	= { .type = NLA_U32 },
490 		[IPSET_ATTR_SKBQUEUE]	= { .type = NLA_U16 },
491 	},
492 	.me		= THIS_MODULE,
493 };
494 
495 static int __init
496 hash_netnet_init(void)
497 {
498 	return ip_set_type_register(&hash_netnet_type);
499 }
500 
501 static void __exit
502 hash_netnet_fini(void)
503 {
504 	rcu_barrier();
505 	ip_set_type_unregister(&hash_netnet_type);
506 }
507 
508 module_init(hash_netnet_init);
509 module_exit(hash_netnet_fini);
510