1// SPDX-License-Identifier: GPL-2.0-only
2/* Copyright (C) 2008-2013 Jozsef Kadlecsik <kadlec@netfilter.org> */
3
4/* Kernel module implementing an IP set type: the list:set type */
5
6#include <linux/module.h>
7#include <linux/ip.h>
8#include <linux/rculist.h>
9#include <linux/skbuff.h>
10#include <linux/errno.h>
11
12#include <linux/netfilter/ipset/ip_set.h>
13#include <linux/netfilter/ipset/ip_set_list.h>
14
15#define IPSET_TYPE_REV_MIN 0
16/* 1 Counters support added */
17/* 2 Comments support added */
18#define IPSET_TYPE_REV_MAX 3 /* skbinfo support added */
19
20MODULE_LICENSE("GPL");
21MODULE_AUTHOR("Jozsef Kadlecsik <kadlec@netfilter.org>");
22IP_SET_MODULE_DESC("list:set", IPSET_TYPE_REV_MIN, IPSET_TYPE_REV_MAX);
23MODULE_ALIAS("ip_set_list:set");
24
25/* Member elements */
26struct set_elem {
27 struct rcu_head rcu;
28 struct list_head list;
29 struct ip_set *set; /* Sigh, in order to cleanup reference */
30 ip_set_id_t id;
31} __aligned(__alignof__(u64));
32
33struct set_adt_elem {
34 ip_set_id_t id;
35 ip_set_id_t refid;
36 int before;
37};
38
39/* Type structure */
40struct list_set {
41 u32 size; /* size of set list array */
42 struct timer_list gc; /* garbage collection */
43 struct ip_set *set; /* attached to this ip_set */
44 struct net *net; /* namespace */
45 struct list_head members; /* the set members */
46};
47
48static int
49list_set_ktest(struct ip_set *set, const struct sk_buff *skb,
50 const struct xt_action_param *par,
51 struct ip_set_adt_opt *opt, const struct ip_set_ext *ext)
52{
53 struct list_set *map = set->data;
54 struct ip_set_ext *mext = &opt->ext;
55 struct set_elem *e;
56 u32 flags = opt->cmdflags;
57 int ret;
58
59 /* Don't lookup sub-counters at all */
60 opt->cmdflags &= ~IPSET_FLAG_MATCH_COUNTERS;
61 if (opt->cmdflags & IPSET_FLAG_SKIP_SUBCOUNTER_UPDATE)
62 opt->cmdflags |= IPSET_FLAG_SKIP_COUNTER_UPDATE;
63 list_for_each_entry_rcu(e, &map->members, list) {
64 ret = ip_set_test(id: e->id, skb, par, opt);
65 if (ret <= 0)
66 continue;
67 if (ip_set_match_extensions(set, ext, mext, flags, data: e))
68 return 1;
69 }
70 return 0;
71}
72
73static int
74list_set_kadd(struct ip_set *set, const struct sk_buff *skb,
75 const struct xt_action_param *par,
76 struct ip_set_adt_opt *opt, const struct ip_set_ext *ext)
77{
78 struct list_set *map = set->data;
79 struct set_elem *e;
80 int ret;
81
82 list_for_each_entry(e, &map->members, list) {
83 if (SET_WITH_TIMEOUT(set) &&
84 ip_set_timeout_expired(ext_timeout(e, set)))
85 continue;
86 ret = ip_set_add(id: e->id, skb, par, opt);
87 if (ret == 0)
88 return ret;
89 }
90 return 0;
91}
92
93static int
94list_set_kdel(struct ip_set *set, const struct sk_buff *skb,
95 const struct xt_action_param *par,
96 struct ip_set_adt_opt *opt, const struct ip_set_ext *ext)
97{
98 struct list_set *map = set->data;
99 struct set_elem *e;
100 int ret;
101
102 list_for_each_entry(e, &map->members, list) {
103 if (SET_WITH_TIMEOUT(set) &&
104 ip_set_timeout_expired(ext_timeout(e, set)))
105 continue;
106 ret = ip_set_del(id: e->id, skb, par, opt);
107 if (ret == 0)
108 return ret;
109 }
110 return 0;
111}
112
113static int
114list_set_kadt(struct ip_set *set, const struct sk_buff *skb,
115 const struct xt_action_param *par,
116 enum ipset_adt adt, struct ip_set_adt_opt *opt)
117{
118 struct ip_set_ext ext = IP_SET_INIT_KEXT(skb, opt, set);
119 int ret = -EINVAL;
120
121 rcu_read_lock();
122 switch (adt) {
123 case IPSET_TEST:
124 ret = list_set_ktest(set, skb, par, opt, ext: &ext);
125 break;
126 case IPSET_ADD:
127 ret = list_set_kadd(set, skb, par, opt, ext: &ext);
128 break;
129 case IPSET_DEL:
130 ret = list_set_kdel(set, skb, par, opt, ext: &ext);
131 break;
132 default:
133 break;
134 }
135 rcu_read_unlock();
136
137 return ret;
138}
139
140/* Userspace interfaces: we are protected by the nfnl mutex */
141
142static void
143__list_set_del_rcu(struct rcu_head * rcu)
144{
145 struct set_elem *e = container_of(rcu, struct set_elem, rcu);
146 struct ip_set *set = e->set;
147
148 ip_set_ext_destroy(set, data: e);
149 kfree(objp: e);
150}
151
152static void
153list_set_del(struct ip_set *set, struct set_elem *e)
154{
155 struct list_set *map = set->data;
156
157 set->elements--;
158 list_del_rcu(entry: &e->list);
159 ip_set_put_byindex(net: map->net, index: e->id);
160 call_rcu(head: &e->rcu, func: __list_set_del_rcu);
161}
162
163static void
164list_set_replace(struct ip_set *set, struct set_elem *e, struct set_elem *old)
165{
166 struct list_set *map = set->data;
167
168 list_replace_rcu(old: &old->list, new: &e->list);
169 ip_set_put_byindex(net: map->net, index: old->id);
170 call_rcu(head: &old->rcu, func: __list_set_del_rcu);
171}
172
173static void
174set_cleanup_entries(struct ip_set *set)
175{
176 struct list_set *map = set->data;
177 struct set_elem *e, *n;
178
179 list_for_each_entry_safe(e, n, &map->members, list)
180 if (ip_set_timeout_expired(ext_timeout(e, set)))
181 list_set_del(set, e);
182}
183
184static int
185list_set_utest(struct ip_set *set, void *value, const struct ip_set_ext *ext,
186 struct ip_set_ext *mext, u32 flags)
187{
188 struct list_set *map = set->data;
189 struct set_adt_elem *d = value;
190 struct set_elem *e, *next, *prev = NULL;
191 int ret;
192
193 list_for_each_entry(e, &map->members, list) {
194 if (SET_WITH_TIMEOUT(set) &&
195 ip_set_timeout_expired(ext_timeout(e, set)))
196 continue;
197 else if (e->id != d->id) {
198 prev = e;
199 continue;
200 }
201
202 if (d->before == 0) {
203 ret = 1;
204 } else if (d->before > 0) {
205 next = list_next_entry(e, list);
206 ret = !list_is_last(list: &e->list, head: &map->members) &&
207 next->id == d->refid;
208 } else {
209 ret = prev && prev->id == d->refid;
210 }
211 return ret;
212 }
213 return 0;
214}
215
216static void
217list_set_init_extensions(struct ip_set *set, const struct ip_set_ext *ext,
218 struct set_elem *e)
219{
220 if (SET_WITH_COUNTER(set))
221 ip_set_init_counter(ext_counter(e, set), ext);
222 if (SET_WITH_COMMENT(set))
223 ip_set_init_comment(set, ext_comment(e, set), ext);
224 if (SET_WITH_SKBINFO(set))
225 ip_set_init_skbinfo(ext_skbinfo(e, set), ext);
226 /* Update timeout last */
227 if (SET_WITH_TIMEOUT(set))
228 ip_set_timeout_set(ext_timeout(e, set), value: ext->timeout);
229}
230
231static int
232list_set_uadd(struct ip_set *set, void *value, const struct ip_set_ext *ext,
233 struct ip_set_ext *mext, u32 flags)
234{
235 struct list_set *map = set->data;
236 struct set_adt_elem *d = value;
237 struct set_elem *e, *n, *prev, *next;
238 bool flag_exist = flags & IPSET_FLAG_EXIST;
239
240 /* Find where to add the new entry */
241 n = prev = next = NULL;
242 list_for_each_entry(e, &map->members, list) {
243 if (SET_WITH_TIMEOUT(set) &&
244 ip_set_timeout_expired(ext_timeout(e, set)))
245 continue;
246 else if (d->id == e->id)
247 n = e;
248 else if (d->before == 0 || e->id != d->refid)
249 continue;
250 else if (d->before > 0)
251 next = e;
252 else
253 prev = e;
254 }
255
256 /* If before/after is used on an empty set */
257 if ((d->before > 0 && !next) ||
258 (d->before < 0 && !prev))
259 return -IPSET_ERR_REF_EXIST;
260
261 /* Re-add already existing element */
262 if (n) {
263 if (!flag_exist)
264 return -IPSET_ERR_EXIST;
265 /* Update extensions */
266 ip_set_ext_destroy(set, data: n);
267 list_set_init_extensions(set, ext, e: n);
268
269 /* Set is already added to the list */
270 ip_set_put_byindex(net: map->net, index: d->id);
271 return 0;
272 }
273 /* Add new entry */
274 if (d->before == 0) {
275 /* Append */
276 n = list_empty(head: &map->members) ? NULL :
277 list_last_entry(&map->members, struct set_elem, list);
278 } else if (d->before > 0) {
279 /* Insert after next element */
280 if (!list_is_last(list: &next->list, head: &map->members))
281 n = list_next_entry(next, list);
282 } else {
283 /* Insert before prev element */
284 if (prev->list.prev != &map->members)
285 n = list_prev_entry(prev, list);
286 }
287 /* Can we replace a timed out entry? */
288 if (n &&
289 !(SET_WITH_TIMEOUT(set) &&
290 ip_set_timeout_expired(ext_timeout(n, set))))
291 n = NULL;
292
293 e = kzalloc(size: set->dsize, GFP_ATOMIC);
294 if (!e)
295 return -ENOMEM;
296 e->id = d->id;
297 e->set = set;
298 INIT_LIST_HEAD(list: &e->list);
299 list_set_init_extensions(set, ext, e);
300 if (n)
301 list_set_replace(set, e, old: n);
302 else if (next)
303 list_add_tail_rcu(new: &e->list, head: &next->list);
304 else if (prev)
305 list_add_rcu(new: &e->list, head: &prev->list);
306 else
307 list_add_tail_rcu(new: &e->list, head: &map->members);
308 set->elements++;
309
310 return 0;
311}
312
313static int
314list_set_udel(struct ip_set *set, void *value, const struct ip_set_ext *ext,
315 struct ip_set_ext *mext, u32 flags)
316{
317 struct list_set *map = set->data;
318 struct set_adt_elem *d = value;
319 struct set_elem *e, *next, *prev = NULL;
320
321 list_for_each_entry(e, &map->members, list) {
322 if (SET_WITH_TIMEOUT(set) &&
323 ip_set_timeout_expired(ext_timeout(e, set)))
324 continue;
325 else if (e->id != d->id) {
326 prev = e;
327 continue;
328 }
329
330 if (d->before > 0) {
331 next = list_next_entry(e, list);
332 if (list_is_last(list: &e->list, head: &map->members) ||
333 next->id != d->refid)
334 return -IPSET_ERR_REF_EXIST;
335 } else if (d->before < 0) {
336 if (!prev || prev->id != d->refid)
337 return -IPSET_ERR_REF_EXIST;
338 }
339 list_set_del(set, e);
340 return 0;
341 }
342 return d->before != 0 ? -IPSET_ERR_REF_EXIST : -IPSET_ERR_EXIST;
343}
344
345static int
346list_set_uadt(struct ip_set *set, struct nlattr *tb[],
347 enum ipset_adt adt, u32 *lineno, u32 flags, bool retried)
348{
349 struct list_set *map = set->data;
350 ipset_adtfn adtfn = set->variant->adt[adt];
351 struct set_adt_elem e = { .refid = IPSET_INVALID_ID };
352 struct ip_set_ext ext = IP_SET_INIT_UEXT(set);
353 struct ip_set *s;
354 int ret = 0;
355
356 if (tb[IPSET_ATTR_LINENO])
357 *lineno = nla_get_u32(nla: tb[IPSET_ATTR_LINENO]);
358
359 if (unlikely(!tb[IPSET_ATTR_NAME] ||
360 !ip_set_optattr_netorder(tb, IPSET_ATTR_CADT_FLAGS)))
361 return -IPSET_ERR_PROTOCOL;
362
363 ret = ip_set_get_extensions(set, tb, ext: &ext);
364 if (ret)
365 return ret;
366 e.id = ip_set_get_byname(net: map->net, name: nla_data(nla: tb[IPSET_ATTR_NAME]), set: &s);
367 if (e.id == IPSET_INVALID_ID)
368 return -IPSET_ERR_NAME;
369 /* "Loop detection" */
370 if (s->type->features & IPSET_TYPE_NAME) {
371 ret = -IPSET_ERR_LOOP;
372 goto finish;
373 }
374
375 if (tb[IPSET_ATTR_CADT_FLAGS]) {
376 u32 f = ip_set_get_h32(attr: tb[IPSET_ATTR_CADT_FLAGS]);
377
378 e.before = f & IPSET_FLAG_BEFORE;
379 }
380
381 if (e.before && !tb[IPSET_ATTR_NAMEREF]) {
382 ret = -IPSET_ERR_BEFORE;
383 goto finish;
384 }
385
386 if (tb[IPSET_ATTR_NAMEREF]) {
387 e.refid = ip_set_get_byname(net: map->net,
388 name: nla_data(nla: tb[IPSET_ATTR_NAMEREF]),
389 set: &s);
390 if (e.refid == IPSET_INVALID_ID) {
391 ret = -IPSET_ERR_NAMEREF;
392 goto finish;
393 }
394 if (!e.before)
395 e.before = -1;
396 }
397 if (adt != IPSET_TEST && SET_WITH_TIMEOUT(set))
398 set_cleanup_entries(set);
399
400 ret = adtfn(set, &e, &ext, &ext, flags);
401
402finish:
403 if (e.refid != IPSET_INVALID_ID)
404 ip_set_put_byindex(net: map->net, index: e.refid);
405 if (adt != IPSET_ADD || ret)
406 ip_set_put_byindex(net: map->net, index: e.id);
407
408 return ip_set_eexist(ret, flags) ? 0 : ret;
409}
410
411static void
412list_set_flush(struct ip_set *set)
413{
414 struct list_set *map = set->data;
415 struct set_elem *e, *n;
416
417 list_for_each_entry_safe(e, n, &map->members, list)
418 list_set_del(set, e);
419 set->elements = 0;
420 set->ext_size = 0;
421}
422
423static void
424list_set_destroy(struct ip_set *set)
425{
426 struct list_set *map = set->data;
427 struct set_elem *e, *n;
428
429 list_for_each_entry_safe(e, n, &map->members, list) {
430 list_del(entry: &e->list);
431 ip_set_put_byindex(net: map->net, index: e->id);
432 ip_set_ext_destroy(set, data: e);
433 kfree(objp: e);
434 }
435 kfree(objp: map);
436
437 set->data = NULL;
438}
439
440/* Calculate the actual memory size of the set data */
441static size_t
442list_set_memsize(const struct list_set *map, size_t dsize)
443{
444 struct set_elem *e;
445 u32 n = 0;
446
447 rcu_read_lock();
448 list_for_each_entry_rcu(e, &map->members, list)
449 n++;
450 rcu_read_unlock();
451
452 return (sizeof(*map) + n * dsize);
453}
454
455static int
456list_set_head(struct ip_set *set, struct sk_buff *skb)
457{
458 const struct list_set *map = set->data;
459 struct nlattr *nested;
460 size_t memsize = list_set_memsize(map, dsize: set->dsize) + set->ext_size;
461
462 nested = nla_nest_start(skb, attrtype: IPSET_ATTR_DATA);
463 if (!nested)
464 goto nla_put_failure;
465 if (nla_put_net32(skb, attrtype: IPSET_ATTR_SIZE, htonl(map->size)) ||
466 nla_put_net32(skb, attrtype: IPSET_ATTR_REFERENCES, htonl(set->ref)) ||
467 nla_put_net32(skb, attrtype: IPSET_ATTR_MEMSIZE, htonl(memsize)) ||
468 nla_put_net32(skb, attrtype: IPSET_ATTR_ELEMENTS, htonl(set->elements)))
469 goto nla_put_failure;
470 if (unlikely(ip_set_put_flags(skb, set)))
471 goto nla_put_failure;
472 nla_nest_end(skb, start: nested);
473
474 return 0;
475nla_put_failure:
476 return -EMSGSIZE;
477}
478
479static int
480list_set_list(const struct ip_set *set,
481 struct sk_buff *skb, struct netlink_callback *cb)
482{
483 const struct list_set *map = set->data;
484 struct nlattr *atd, *nested;
485 u32 i = 0, first = cb->args[IPSET_CB_ARG0];
486 char name[IPSET_MAXNAMELEN];
487 struct set_elem *e;
488 int ret = 0;
489
490 atd = nla_nest_start(skb, attrtype: IPSET_ATTR_ADT);
491 if (!atd)
492 return -EMSGSIZE;
493
494 rcu_read_lock();
495 list_for_each_entry_rcu(e, &map->members, list) {
496 if (i < first ||
497 (SET_WITH_TIMEOUT(set) &&
498 ip_set_timeout_expired(ext_timeout(e, set)))) {
499 i++;
500 continue;
501 }
502 nested = nla_nest_start(skb, attrtype: IPSET_ATTR_DATA);
503 if (!nested)
504 goto nla_put_failure;
505 ip_set_name_byindex(net: map->net, index: e->id, name);
506 if (nla_put_string(skb, attrtype: IPSET_ATTR_NAME, str: name))
507 goto nla_put_failure;
508 if (ip_set_put_extensions(skb, set, e, active: true))
509 goto nla_put_failure;
510 nla_nest_end(skb, start: nested);
511 i++;
512 }
513
514 nla_nest_end(skb, start: atd);
515 /* Set listing finished */
516 cb->args[IPSET_CB_ARG0] = 0;
517 goto out;
518
519nla_put_failure:
520 nla_nest_cancel(skb, start: nested);
521 if (unlikely(i == first)) {
522 nla_nest_cancel(skb, start: atd);
523 cb->args[IPSET_CB_ARG0] = 0;
524 ret = -EMSGSIZE;
525 } else {
526 cb->args[IPSET_CB_ARG0] = i;
527 nla_nest_end(skb, start: atd);
528 }
529out:
530 rcu_read_unlock();
531 return ret;
532}
533
534static bool
535list_set_same_set(const struct ip_set *a, const struct ip_set *b)
536{
537 const struct list_set *x = a->data;
538 const struct list_set *y = b->data;
539
540 return x->size == y->size &&
541 a->timeout == b->timeout &&
542 a->extensions == b->extensions;
543}
544
545static void
546list_set_cancel_gc(struct ip_set *set)
547{
548 struct list_set *map = set->data;
549
550 if (SET_WITH_TIMEOUT(set))
551 timer_shutdown_sync(timer: &map->gc);
552}
553
554static const struct ip_set_type_variant set_variant = {
555 .kadt = list_set_kadt,
556 .uadt = list_set_uadt,
557 .adt = {
558 [IPSET_ADD] = list_set_uadd,
559 [IPSET_DEL] = list_set_udel,
560 [IPSET_TEST] = list_set_utest,
561 },
562 .destroy = list_set_destroy,
563 .flush = list_set_flush,
564 .head = list_set_head,
565 .list = list_set_list,
566 .same_set = list_set_same_set,
567 .cancel_gc = list_set_cancel_gc,
568};
569
570static void
571list_set_gc(struct timer_list *t)
572{
573 struct list_set *map = from_timer(map, t, gc);
574 struct ip_set *set = map->set;
575
576 spin_lock_bh(lock: &set->lock);
577 set_cleanup_entries(set);
578 spin_unlock_bh(lock: &set->lock);
579
580 map->gc.expires = jiffies + IPSET_GC_PERIOD(set->timeout) * HZ;
581 add_timer(timer: &map->gc);
582}
583
584static void
585list_set_gc_init(struct ip_set *set, void (*gc)(struct timer_list *t))
586{
587 struct list_set *map = set->data;
588
589 timer_setup(&map->gc, gc, 0);
590 mod_timer(timer: &map->gc, expires: jiffies + IPSET_GC_PERIOD(set->timeout) * HZ);
591}
592
593/* Create list:set type of sets */
594
595static bool
596init_list_set(struct net *net, struct ip_set *set, u32 size)
597{
598 struct list_set *map;
599
600 map = kzalloc(size: sizeof(*map), GFP_KERNEL);
601 if (!map)
602 return false;
603
604 map->size = size;
605 map->net = net;
606 map->set = set;
607 INIT_LIST_HEAD(list: &map->members);
608 set->data = map;
609
610 return true;
611}
612
613static int
614list_set_create(struct net *net, struct ip_set *set, struct nlattr *tb[],
615 u32 flags)
616{
617 u32 size = IP_SET_LIST_DEFAULT_SIZE;
618
619 if (unlikely(!ip_set_optattr_netorder(tb, IPSET_ATTR_SIZE) ||
620 !ip_set_optattr_netorder(tb, IPSET_ATTR_TIMEOUT) ||
621 !ip_set_optattr_netorder(tb, IPSET_ATTR_CADT_FLAGS)))
622 return -IPSET_ERR_PROTOCOL;
623
624 if (tb[IPSET_ATTR_SIZE])
625 size = ip_set_get_h32(attr: tb[IPSET_ATTR_SIZE]);
626 if (size < IP_SET_LIST_MIN_SIZE)
627 size = IP_SET_LIST_MIN_SIZE;
628
629 set->variant = &set_variant;
630 set->dsize = ip_set_elem_len(set, tb, len: sizeof(struct set_elem),
631 align: __alignof__(struct set_elem));
632 if (!init_list_set(net, set, size))
633 return -ENOMEM;
634 if (tb[IPSET_ATTR_TIMEOUT]) {
635 set->timeout = ip_set_timeout_uget(tb: tb[IPSET_ATTR_TIMEOUT]);
636 list_set_gc_init(set, gc: list_set_gc);
637 }
638 return 0;
639}
640
641static struct ip_set_type list_set_type __read_mostly = {
642 .name = "list:set",
643 .protocol = IPSET_PROTOCOL,
644 .features = IPSET_TYPE_NAME | IPSET_DUMP_LAST,
645 .dimension = IPSET_DIM_ONE,
646 .family = NFPROTO_UNSPEC,
647 .revision_min = IPSET_TYPE_REV_MIN,
648 .revision_max = IPSET_TYPE_REV_MAX,
649 .create = list_set_create,
650 .create_policy = {
651 [IPSET_ATTR_SIZE] = { .type = NLA_U32 },
652 [IPSET_ATTR_TIMEOUT] = { .type = NLA_U32 },
653 [IPSET_ATTR_CADT_FLAGS] = { .type = NLA_U32 },
654 },
655 .adt_policy = {
656 [IPSET_ATTR_NAME] = { .type = NLA_STRING,
657 .len = IPSET_MAXNAMELEN },
658 [IPSET_ATTR_NAMEREF] = { .type = NLA_STRING,
659 .len = IPSET_MAXNAMELEN },
660 [IPSET_ATTR_TIMEOUT] = { .type = NLA_U32 },
661 [IPSET_ATTR_LINENO] = { .type = NLA_U32 },
662 [IPSET_ATTR_CADT_FLAGS] = { .type = NLA_U32 },
663 [IPSET_ATTR_BYTES] = { .type = NLA_U64 },
664 [IPSET_ATTR_PACKETS] = { .type = NLA_U64 },
665 [IPSET_ATTR_COMMENT] = { .type = NLA_NUL_STRING,
666 .len = IPSET_MAX_COMMENT_SIZE },
667 [IPSET_ATTR_SKBMARK] = { .type = NLA_U64 },
668 [IPSET_ATTR_SKBPRIO] = { .type = NLA_U32 },
669 [IPSET_ATTR_SKBQUEUE] = { .type = NLA_U16 },
670 },
671 .me = THIS_MODULE,
672};
673
674static int __init
675list_set_init(void)
676{
677 return ip_set_type_register(set_type: &list_set_type);
678}
679
680static void __exit
681list_set_fini(void)
682{
683 rcu_barrier();
684 ip_set_type_unregister(set_type: &list_set_type);
685}
686
687module_init(list_set_init);
688module_exit(list_set_fini);
689

source code of linux/net/netfilter/ipset/ip_set_list_set.c