xref: /linux/net/netfilter/ipset/ip_set_hash_netiface.c (revision 42874e4eb35bdfc54f8514685e50434098ba4f6c) 
1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Copyright (C) 2011-2013 Jozsef Kadlecsik <kadlec@netfilter.org> */
3 
4 /* Kernel module implementing an IP set type: the hash:net,iface type */
5 
6 #include <linux/jhash.h>
7 #include <linux/module.h>
8 #include <linux/ip.h>
9 #include <linux/skbuff.h>
10 #include <linux/errno.h>
11 #include <linux/random.h>
12 #include <net/ip.h>
13 #include <net/ipv6.h>
14 #include <net/netlink.h>
15 
16 #include <linux/netfilter.h>
17 #include <linux/netfilter_bridge.h>
18 #include <linux/netfilter/ipset/pfxlen.h>
19 #include <linux/netfilter/ipset/ip_set.h>
20 #include <linux/netfilter/ipset/ip_set_hash.h>
21 
22 #define IPSET_TYPE_REV_MIN	0
23 /*				1    nomatch flag support added */
24 /*				2    /0 support added */
25 /*				3    Counters support added */
26 /*				4    Comments support added */
27 /*				5    Forceadd support added */
28 /*				6    skbinfo support added */
29 /*				7    interface wildcard support added */
30 #define IPSET_TYPE_REV_MAX	8 /* bucketsize, initval support added */
31 
32 MODULE_LICENSE("GPL");
33 MODULE_AUTHOR("Jozsef Kadlecsik <kadlec@netfilter.org>");
34 IP_SET_MODULE_DESC("hash:net,iface", IPSET_TYPE_REV_MIN, IPSET_TYPE_REV_MAX);
35 MODULE_ALIAS("ip_set_hash:net,iface");
36 
37 /* Type specific function prefix */
38 #define HTYPE		hash_netiface
39 #define IP_SET_HASH_WITH_NETS
40 #define IP_SET_HASH_WITH_MULTI
41 #define IP_SET_HASH_WITH_NET0
42 
43 #define STRSCPY(a, b)	strscpy(a, b, IFNAMSIZ)
44 
45 /* IPv4 variant */
46 
47 struct hash_netiface4_elem_hashed {
48 	__be32 ip;
49 	u8 physdev;
50 	u8 cidr;
51 	u8 nomatch;
52 	u8 elem;
53 };
54 
55 /* Member elements */
56 struct hash_netiface4_elem {
57 	__be32 ip;
58 	u8 physdev;
59 	u8 cidr;
60 	u8 nomatch;
61 	u8 elem;
62 	u8 wildcard;
63 	char iface[IFNAMSIZ];
64 };
65 
66 /* Common functions */
67 
68 static bool
69 hash_netiface4_data_equal(const struct hash_netiface4_elem *ip1,
70 			  const struct hash_netiface4_elem *ip2,
71 			  u32 *multi)
72 {
73 	return ip1->ip == ip2->ip &&
74 	       ip1->cidr == ip2->cidr &&
75 	       (++*multi) &&
76 	       ip1->physdev == ip2->physdev &&
77 	       (ip1->wildcard ?
78 		strncmp(ip1->iface, ip2->iface, strlen(ip1->iface)) == 0 :
79 		strcmp(ip1->iface, ip2->iface) == 0);
80 }
81 
82 static int
83 hash_netiface4_do_data_match(const struct hash_netiface4_elem *elem)
84 {
85 	return elem->nomatch ? -ENOTEMPTY : 1;
86 }
87 
88 static void
89 hash_netiface4_data_set_flags(struct hash_netiface4_elem *elem, u32 flags)
90 {
91 	elem->nomatch = (flags >> 16) & IPSET_FLAG_NOMATCH;
92 }
93 
94 static void
95 hash_netiface4_data_reset_flags(struct hash_netiface4_elem *elem, u8 *flags)
96 {
97 	swap(*flags, elem->nomatch);
98 }
99 
100 static void
101 hash_netiface4_data_netmask(struct hash_netiface4_elem *elem, u8 cidr)
102 {
103 	elem->ip &= ip_set_netmask(cidr);
104 	elem->cidr = cidr;
105 }
106 
107 static bool
108 hash_netiface4_data_list(struct sk_buff *skb,
109 			 const struct hash_netiface4_elem *data)
110 {
111 	u32 flags = (data->physdev ? IPSET_FLAG_PHYSDEV : 0) |
112 		    (data->wildcard ? IPSET_FLAG_IFACE_WILDCARD : 0);
113 
114 	if (data->nomatch)
115 		flags |= IPSET_FLAG_NOMATCH;
116 	if (nla_put_ipaddr4(skb, IPSET_ATTR_IP, data->ip) ||
117 	    nla_put_u8(skb, IPSET_ATTR_CIDR, data->cidr) ||
118 	    nla_put_string(skb, IPSET_ATTR_IFACE, data->iface) ||
119 	    (flags &&
120 	     nla_put_net32(skb, IPSET_ATTR_CADT_FLAGS, htonl(flags))))
121 		goto nla_put_failure;
122 	return false;
123 
124 nla_put_failure:
125 	return true;
126 }
127 
128 static void
129 hash_netiface4_data_next(struct hash_netiface4_elem *next,
130 			 const struct hash_netiface4_elem *d)
131 {
132 	next->ip = d->ip;
133 }
134 
135 #define MTYPE		hash_netiface4
136 #define HOST_MASK	32
137 #define HKEY_DATALEN	sizeof(struct hash_netiface4_elem_hashed)
138 #include "ip_set_hash_gen.h"
139 
140 #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
141 static const char *get_physindev_name(const struct sk_buff *skb)
142 {
143 	struct net_device *dev = nf_bridge_get_physindev(skb);
144 
145 	return dev ? dev->name : NULL;
146 }
147 
148 static const char *get_physoutdev_name(const struct sk_buff *skb)
149 {
150 	struct net_device *dev = nf_bridge_get_physoutdev(skb);
151 
152 	return dev ? dev->name : NULL;
153 }
154 #endif
155 
156 static int
157 hash_netiface4_kadt(struct ip_set *set, const struct sk_buff *skb,
158 		    const struct xt_action_param *par,
159 		    enum ipset_adt adt, struct ip_set_adt_opt *opt)
160 {
161 	struct hash_netiface4 *h = set->data;
162 	ipset_adtfn adtfn = set->variant->adt[adt];
163 	struct hash_netiface4_elem e = {
164 		.cidr = INIT_CIDR(h->nets[0].cidr[0], HOST_MASK),
165 		.elem = 1,
166 	};
167 	struct ip_set_ext ext = IP_SET_INIT_KEXT(skb, opt, set);
168 
169 	if (adt == IPSET_TEST)
170 		e.cidr = HOST_MASK;
171 
172 	ip4addrptr(skb, opt->flags & IPSET_DIM_ONE_SRC, &e.ip);
173 	e.ip &= ip_set_netmask(e.cidr);
174 
175 #define IFACE(dir)	(par->state->dir ? par->state->dir->name : "")
176 #define SRCDIR		(opt->flags & IPSET_DIM_TWO_SRC)
177 
178 	if (opt->cmdflags & IPSET_FLAG_PHYSDEV) {
179 #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
180 		const char *eiface = SRCDIR ? get_physindev_name(skb) :
181 					      get_physoutdev_name(skb);
182 
183 		if (!eiface)
184 			return -EINVAL;
185 		STRSCPY(e.iface, eiface);
186 		e.physdev = 1;
187 #endif
188 	} else {
189 		STRSCPY(e.iface, SRCDIR ? IFACE(in) : IFACE(out));
190 	}
191 
192 	if (strlen(e.iface) == 0)
193 		return -EINVAL;
194 	return adtfn(set, &e, &ext, &opt->ext, opt->cmdflags);
195 }
196 
197 static int
198 hash_netiface4_uadt(struct ip_set *set, struct nlattr *tb[],
199 		    enum ipset_adt adt, u32 *lineno, u32 flags, bool retried)
200 {
201 	struct hash_netiface4 *h = set->data;
202 	ipset_adtfn adtfn = set->variant->adt[adt];
203 	struct hash_netiface4_elem e = { .cidr = HOST_MASK, .elem = 1 };
204 	struct ip_set_ext ext = IP_SET_INIT_UEXT(set);
205 	u32 ip = 0, ip_to = 0, i = 0;
206 	int ret;
207 
208 	if (tb[IPSET_ATTR_LINENO])
209 		*lineno = nla_get_u32(tb[IPSET_ATTR_LINENO]);
210 
211 	if (unlikely(!tb[IPSET_ATTR_IP] ||
212 		     !tb[IPSET_ATTR_IFACE] ||
213 		     !ip_set_optattr_netorder(tb, IPSET_ATTR_CADT_FLAGS)))
214 		return -IPSET_ERR_PROTOCOL;
215 
216 	ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP], &ip);
217 	if (ret)
218 		return ret;
219 
220 	ret = ip_set_get_extensions(set, tb, &ext);
221 	if (ret)
222 		return ret;
223 
224 	if (tb[IPSET_ATTR_CIDR]) {
225 		e.cidr = nla_get_u8(tb[IPSET_ATTR_CIDR]);
226 		if (e.cidr > HOST_MASK)
227 			return -IPSET_ERR_INVALID_CIDR;
228 	}
229 	nla_strscpy(e.iface, tb[IPSET_ATTR_IFACE], IFNAMSIZ);
230 
231 	if (tb[IPSET_ATTR_CADT_FLAGS]) {
232 		u32 cadt_flags = ip_set_get_h32(tb[IPSET_ATTR_CADT_FLAGS]);
233 
234 		if (cadt_flags & IPSET_FLAG_PHYSDEV)
235 			e.physdev = 1;
236 		if (cadt_flags & IPSET_FLAG_NOMATCH)
237 			flags |= (IPSET_FLAG_NOMATCH << 16);
238 		if (cadt_flags & IPSET_FLAG_IFACE_WILDCARD)
239 			e.wildcard = 1;
240 	}
241 	if (adt == IPSET_TEST || !tb[IPSET_ATTR_IP_TO]) {
242 		e.ip = htonl(ip & ip_set_hostmask(e.cidr));
243 		ret = adtfn(set, &e, &ext, &ext, flags);
244 		return ip_set_enomatch(ret, flags, adt, set) ? -ret :
245 		       ip_set_eexist(ret, flags) ? 0 : ret;
246 	}
247 
248 	if (tb[IPSET_ATTR_IP_TO]) {
249 		ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP_TO], &ip_to);
250 		if (ret)
251 			return ret;
252 		if (ip_to < ip)
253 			swap(ip, ip_to);
254 		if (ip + UINT_MAX == ip_to)
255 			return -IPSET_ERR_HASH_RANGE;
256 	} else {
257 		ip_set_mask_from_to(ip, ip_to, e.cidr);
258 	}
259 
260 	if (retried)
261 		ip = ntohl(h->next.ip);
262 	do {
263 		i++;
264 		e.ip = htonl(ip);
265 		if (i > IPSET_MAX_RANGE) {
266 			hash_netiface4_data_next(&h->next, &e);
267 			return -ERANGE;
268 		}
269 		ip = ip_set_range_to_cidr(ip, ip_to, &e.cidr);
270 		ret = adtfn(set, &e, &ext, &ext, flags);
271 
272 		if (ret && !ip_set_eexist(ret, flags))
273 			return ret;
274 
275 		ret = 0;
276 	} while (ip++ < ip_to);
277 	return ret;
278 }
279 
280 /* IPv6 variant */
281 
282 struct hash_netiface6_elem_hashed {
283 	union nf_inet_addr ip;
284 	u8 physdev;
285 	u8 cidr;
286 	u8 nomatch;
287 	u8 elem;
288 };
289 
290 struct hash_netiface6_elem {
291 	union nf_inet_addr ip;
292 	u8 physdev;
293 	u8 cidr;
294 	u8 nomatch;
295 	u8 elem;
296 	u8 wildcard;
297 	char iface[IFNAMSIZ];
298 };
299 
300 /* Common functions */
301 
302 static bool
303 hash_netiface6_data_equal(const struct hash_netiface6_elem *ip1,
304 			  const struct hash_netiface6_elem *ip2,
305 			  u32 *multi)
306 {
307 	return ipv6_addr_equal(&ip1->ip.in6, &ip2->ip.in6) &&
308 	       ip1->cidr == ip2->cidr &&
309 	       (++*multi) &&
310 	       ip1->physdev == ip2->physdev &&
311 	       (ip1->wildcard ?
312 		strncmp(ip1->iface, ip2->iface, strlen(ip1->iface)) == 0 :
313 		strcmp(ip1->iface, ip2->iface) == 0);
314 }
315 
316 static int
317 hash_netiface6_do_data_match(const struct hash_netiface6_elem *elem)
318 {
319 	return elem->nomatch ? -ENOTEMPTY : 1;
320 }
321 
322 static void
323 hash_netiface6_data_set_flags(struct hash_netiface6_elem *elem, u32 flags)
324 {
325 	elem->nomatch = (flags >> 16) & IPSET_FLAG_NOMATCH;
326 }
327 
328 static void
329 hash_netiface6_data_reset_flags(struct hash_netiface6_elem *elem, u8 *flags)
330 {
331 	swap(*flags, elem->nomatch);
332 }
333 
334 static void
335 hash_netiface6_data_netmask(struct hash_netiface6_elem *elem, u8 cidr)
336 {
337 	ip6_netmask(&elem->ip, cidr);
338 	elem->cidr = cidr;
339 }
340 
341 static bool
342 hash_netiface6_data_list(struct sk_buff *skb,
343 			 const struct hash_netiface6_elem *data)
344 {
345 	u32 flags = (data->physdev ? IPSET_FLAG_PHYSDEV : 0) |
346 		    (data->wildcard ? IPSET_FLAG_IFACE_WILDCARD : 0);
347 
348 	if (data->nomatch)
349 		flags |= IPSET_FLAG_NOMATCH;
350 	if (nla_put_ipaddr6(skb, IPSET_ATTR_IP, &data->ip.in6) ||
351 	    nla_put_u8(skb, IPSET_ATTR_CIDR, data->cidr) ||
352 	    nla_put_string(skb, IPSET_ATTR_IFACE, data->iface) ||
353 	    (flags &&
354 	     nla_put_net32(skb, IPSET_ATTR_CADT_FLAGS, htonl(flags))))
355 		goto nla_put_failure;
356 	return false;
357 
358 nla_put_failure:
359 	return true;
360 }
361 
362 static void
363 hash_netiface6_data_next(struct hash_netiface6_elem *next,
364 			 const struct hash_netiface6_elem *d)
365 {
366 }
367 
368 #undef MTYPE
369 #undef HOST_MASK
370 
371 #define MTYPE		hash_netiface6
372 #define HOST_MASK	128
373 #define HKEY_DATALEN	sizeof(struct hash_netiface6_elem_hashed)
374 #define IP_SET_EMIT_CREATE
375 #include "ip_set_hash_gen.h"
376 
377 static int
378 hash_netiface6_kadt(struct ip_set *set, const struct sk_buff *skb,
379 		    const struct xt_action_param *par,
380 		    enum ipset_adt adt, struct ip_set_adt_opt *opt)
381 {
382 	struct hash_netiface6 *h = set->data;
383 	ipset_adtfn adtfn = set->variant->adt[adt];
384 	struct hash_netiface6_elem e = {
385 		.cidr = INIT_CIDR(h->nets[0].cidr[0], HOST_MASK),
386 		.elem = 1,
387 	};
388 	struct ip_set_ext ext = IP_SET_INIT_KEXT(skb, opt, set);
389 
390 	if (adt == IPSET_TEST)
391 		e.cidr = HOST_MASK;
392 
393 	ip6addrptr(skb, opt->flags & IPSET_DIM_ONE_SRC, &e.ip.in6);
394 	ip6_netmask(&e.ip, e.cidr);
395 
396 	if (opt->cmdflags & IPSET_FLAG_PHYSDEV) {
397 #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
398 		const char *eiface = SRCDIR ? get_physindev_name(skb) :
399 					      get_physoutdev_name(skb);
400 
401 		if (!eiface)
402 			return -EINVAL;
403 		STRSCPY(e.iface, eiface);
404 		e.physdev = 1;
405 #endif
406 	} else {
407 		STRSCPY(e.iface, SRCDIR ? IFACE(in) : IFACE(out));
408 	}
409 
410 	if (strlen(e.iface) == 0)
411 		return -EINVAL;
412 
413 	return adtfn(set, &e, &ext, &opt->ext, opt->cmdflags);
414 }
415 
416 static int
417 hash_netiface6_uadt(struct ip_set *set, struct nlattr *tb[],
418 		    enum ipset_adt adt, u32 *lineno, u32 flags, bool retried)
419 {
420 	ipset_adtfn adtfn = set->variant->adt[adt];
421 	struct hash_netiface6_elem e = { .cidr = HOST_MASK, .elem = 1 };
422 	struct ip_set_ext ext = IP_SET_INIT_UEXT(set);
423 	int ret;
424 
425 	if (tb[IPSET_ATTR_LINENO])
426 		*lineno = nla_get_u32(tb[IPSET_ATTR_LINENO]);
427 
428 	if (unlikely(!tb[IPSET_ATTR_IP] ||
429 		     !tb[IPSET_ATTR_IFACE] ||
430 		     !ip_set_optattr_netorder(tb, IPSET_ATTR_CADT_FLAGS)))
431 		return -IPSET_ERR_PROTOCOL;
432 	if (unlikely(tb[IPSET_ATTR_IP_TO]))
433 		return -IPSET_ERR_HASH_RANGE_UNSUPPORTED;
434 
435 	ret = ip_set_get_ipaddr6(tb[IPSET_ATTR_IP], &e.ip);
436 	if (ret)
437 		return ret;
438 
439 	ret = ip_set_get_extensions(set, tb, &ext);
440 	if (ret)
441 		return ret;
442 
443 	if (tb[IPSET_ATTR_CIDR]) {
444 		e.cidr = nla_get_u8(tb[IPSET_ATTR_CIDR]);
445 		if (e.cidr > HOST_MASK)
446 			return -IPSET_ERR_INVALID_CIDR;
447 	}
448 
449 	ip6_netmask(&e.ip, e.cidr);
450 
451 	nla_strscpy(e.iface, tb[IPSET_ATTR_IFACE], IFNAMSIZ);
452 
453 	if (tb[IPSET_ATTR_CADT_FLAGS]) {
454 		u32 cadt_flags = ip_set_get_h32(tb[IPSET_ATTR_CADT_FLAGS]);
455 
456 		if (cadt_flags & IPSET_FLAG_PHYSDEV)
457 			e.physdev = 1;
458 		if (cadt_flags & IPSET_FLAG_NOMATCH)
459 			flags |= (IPSET_FLAG_NOMATCH << 16);
460 		if (cadt_flags & IPSET_FLAG_IFACE_WILDCARD)
461 			e.wildcard = 1;
462 	}
463 
464 	ret = adtfn(set, &e, &ext, &ext, flags);
465 
466 	return ip_set_enomatch(ret, flags, adt, set) ? -ret :
467 	       ip_set_eexist(ret, flags) ? 0 : ret;
468 }
469 
470 static struct ip_set_type hash_netiface_type __read_mostly = {
471 	.name		= "hash:net,iface",
472 	.protocol	= IPSET_PROTOCOL,
473 	.features	= IPSET_TYPE_IP | IPSET_TYPE_IFACE |
474 			  IPSET_TYPE_NOMATCH,
475 	.dimension	= IPSET_DIM_TWO,
476 	.family		= NFPROTO_UNSPEC,
477 	.revision_min	= IPSET_TYPE_REV_MIN,
478 	.revision_max	= IPSET_TYPE_REV_MAX,
479 	.create_flags[IPSET_TYPE_REV_MAX] = IPSET_CREATE_FLAG_BUCKETSIZE,
480 	.create		= hash_netiface_create,
481 	.create_policy	= {
482 		[IPSET_ATTR_HASHSIZE]	= { .type = NLA_U32 },
483 		[IPSET_ATTR_MAXELEM]	= { .type = NLA_U32 },
484 		[IPSET_ATTR_INITVAL]	= { .type = NLA_U32 },
485 		[IPSET_ATTR_BUCKETSIZE]	= { .type = NLA_U8 },
486 		[IPSET_ATTR_RESIZE]	= { .type = NLA_U8  },
487 		[IPSET_ATTR_PROTO]	= { .type = NLA_U8 },
488 		[IPSET_ATTR_TIMEOUT]	= { .type = NLA_U32 },
489 		[IPSET_ATTR_CADT_FLAGS]	= { .type = NLA_U32 },
490 	},
491 	.adt_policy	= {
492 		[IPSET_ATTR_IP]		= { .type = NLA_NESTED },
493 		[IPSET_ATTR_IP_TO]	= { .type = NLA_NESTED },
494 		[IPSET_ATTR_IFACE]	= { .type = NLA_NUL_STRING,
495 					    .len  = IFNAMSIZ - 1 },
496 		[IPSET_ATTR_CADT_FLAGS]	= { .type = NLA_U32 },
497 		[IPSET_ATTR_CIDR]	= { .type = NLA_U8 },
498 		[IPSET_ATTR_TIMEOUT]	= { .type = NLA_U32 },
499 		[IPSET_ATTR_LINENO]	= { .type = NLA_U32 },
500 		[IPSET_ATTR_BYTES]	= { .type = NLA_U64 },
501 		[IPSET_ATTR_PACKETS]	= { .type = NLA_U64 },
502 		[IPSET_ATTR_COMMENT]	= { .type = NLA_NUL_STRING,
503 					    .len  = IPSET_MAX_COMMENT_SIZE },
504 		[IPSET_ATTR_SKBMARK]	= { .type = NLA_U64 },
505 		[IPSET_ATTR_SKBPRIO]	= { .type = NLA_U32 },
506 		[IPSET_ATTR_SKBQUEUE]	= { .type = NLA_U16 },
507 	},
508 	.me		= THIS_MODULE,
509 };
510 
511 static int __init
512 hash_netiface_init(void)
513 {
514 	return ip_set_type_register(&hash_netiface_type);
515 }
516 
517 static void __exit
518 hash_netiface_fini(void)
519 {
520 	rcu_barrier();
521 	ip_set_type_unregister(&hash_netiface_type);
522 }
523 
524 module_init(hash_netiface_init);
525 module_exit(hash_netiface_fini);
526