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