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
32MODULE_LICENSE("GPL");
33MODULE_AUTHOR("Jozsef Kadlecsik <kadlec@netfilter.org>");
34IP_SET_MODULE_DESC("hash:net,iface", IPSET_TYPE_REV_MIN, IPSET_TYPE_REV_MAX);
35MODULE_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
47struct hash_netiface4_elem_hashed {
48	__be32 ip;
49	u8 physdev;
50	u8 cidr;
51	u8 nomatch;
52	u8 elem;
53};
54
55/* Member elements */
56struct 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
68static bool
69hash_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
82static int
83hash_netiface4_do_data_match(const struct hash_netiface4_elem *elem)
84{
85	return elem->nomatch ? -ENOTEMPTY : 1;
86}
87
88static void
89hash_netiface4_data_set_flags(struct hash_netiface4_elem *elem, u32 flags)
90{
91	elem->nomatch = (flags >> 16) & IPSET_FLAG_NOMATCH;
92}
93
94static void
95hash_netiface4_data_reset_flags(struct hash_netiface4_elem *elem, u8 *flags)
96{
97	swap(*flags, elem->nomatch);
98}
99
100static void
101hash_netiface4_data_netmask(struct hash_netiface4_elem *elem, u8 cidr)
102{
103	elem->ip &= ip_set_netmask(cidr);
104	elem->cidr = cidr;
105}
106
107static bool
108hash_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
124nla_put_failure:
125	return true;
126}
127
128static void
129hash_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)
141static const char *get_physindev_name(const struct sk_buff *skb, struct net *net)
142{
143	struct net_device *dev = nf_bridge_get_physindev(skb, net);
144
145	return dev ? dev->name : NULL;
146}
147
148static 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
156static int
157hash_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, xt_net(par)) :
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
197static int
198hash_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
282struct hash_netiface6_elem_hashed {
283	union nf_inet_addr ip;
284	u8 physdev;
285	u8 cidr;
286	u8 nomatch;
287	u8 elem;
288};
289
290struct 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
302static bool
303hash_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
316static int
317hash_netiface6_do_data_match(const struct hash_netiface6_elem *elem)
318{
319	return elem->nomatch ? -ENOTEMPTY : 1;
320}
321
322static void
323hash_netiface6_data_set_flags(struct hash_netiface6_elem *elem, u32 flags)
324{
325	elem->nomatch = (flags >> 16) & IPSET_FLAG_NOMATCH;
326}
327
328static void
329hash_netiface6_data_reset_flags(struct hash_netiface6_elem *elem, u8 *flags)
330{
331	swap(*flags, elem->nomatch);
332}
333
334static void
335hash_netiface6_data_netmask(struct hash_netiface6_elem *elem, u8 cidr)
336{
337	ip6_netmask(&elem->ip, cidr);
338	elem->cidr = cidr;
339}
340
341static bool
342hash_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
358nla_put_failure:
359	return true;
360}
361
362static void
363hash_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
377static int
378hash_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, xt_net(par)) :
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
416static int
417hash_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
470static 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
511static int __init
512hash_netiface_init(void)
513{
514	return ip_set_type_register(&hash_netiface_type);
515}
516
517static void __exit
518hash_netiface_fini(void)
519{
520	rcu_barrier();
521	ip_set_type_unregister(&hash_netiface_type);
522}
523
524module_init(hash_netiface_init);
525module_exit(hash_netiface_fini);
526