1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net>
4 *
5 * Development of this code funded by Astaro AG (http://www.astaro.com/)
6 */
7
8#include <linux/kernel.h>
9#include <linux/init.h>
10#include <linux/module.h>
11#include <linux/list.h>
12#include <linux/rbtree.h>
13#include <linux/netlink.h>
14#include <linux/netfilter.h>
15#include <linux/netfilter/nf_tables.h>
16#include <net/netfilter/nf_tables_core.h>
17
18struct nft_rbtree {
19 struct rb_root root;
20 rwlock_t lock;
21 seqcount_rwlock_t count;
22 unsigned long last_gc;
23};
24
25struct nft_rbtree_elem {
26 struct nft_elem_priv priv;
27 struct rb_node node;
28 struct nft_set_ext ext;
29};
30
31static bool nft_rbtree_interval_end(const struct nft_rbtree_elem *rbe)
32{
33 return nft_set_ext_exists(ext: &rbe->ext, id: NFT_SET_EXT_FLAGS) &&
34 (*nft_set_ext_flags(ext: &rbe->ext) & NFT_SET_ELEM_INTERVAL_END);
35}
36
37static bool nft_rbtree_interval_start(const struct nft_rbtree_elem *rbe)
38{
39 return !nft_rbtree_interval_end(rbe);
40}
41
42static int nft_rbtree_cmp(const struct nft_set *set,
43 const struct nft_rbtree_elem *e1,
44 const struct nft_rbtree_elem *e2)
45{
46 return memcmp(p: nft_set_ext_key(ext: &e1->ext), q: nft_set_ext_key(ext: &e2->ext),
47 size: set->klen);
48}
49
50static bool nft_rbtree_elem_expired(const struct nft_rbtree_elem *rbe)
51{
52 return nft_set_elem_expired(ext: &rbe->ext);
53}
54
55static bool __nft_rbtree_lookup(const struct net *net, const struct nft_set *set,
56 const u32 *key, const struct nft_set_ext **ext,
57 unsigned int seq)
58{
59 struct nft_rbtree *priv = nft_set_priv(set);
60 const struct nft_rbtree_elem *rbe, *interval = NULL;
61 u8 genmask = nft_genmask_cur(net);
62 const struct rb_node *parent;
63 int d;
64
65 parent = rcu_dereference_raw(priv->root.rb_node);
66 while (parent != NULL) {
67 if (read_seqcount_retry(&priv->count, seq))
68 return false;
69
70 rbe = rb_entry(parent, struct nft_rbtree_elem, node);
71
72 d = memcmp(p: nft_set_ext_key(ext: &rbe->ext), q: key, size: set->klen);
73 if (d < 0) {
74 parent = rcu_dereference_raw(parent->rb_left);
75 if (interval &&
76 !nft_rbtree_cmp(set, e1: rbe, e2: interval) &&
77 nft_rbtree_interval_end(rbe) &&
78 nft_rbtree_interval_start(rbe: interval))
79 continue;
80 interval = rbe;
81 } else if (d > 0)
82 parent = rcu_dereference_raw(parent->rb_right);
83 else {
84 if (!nft_set_elem_active(ext: &rbe->ext, genmask)) {
85 parent = rcu_dereference_raw(parent->rb_left);
86 continue;
87 }
88
89 if (nft_rbtree_elem_expired(rbe))
90 return false;
91
92 if (nft_rbtree_interval_end(rbe)) {
93 if (nft_set_is_anonymous(set))
94 return false;
95 parent = rcu_dereference_raw(parent->rb_left);
96 interval = NULL;
97 continue;
98 }
99
100 *ext = &rbe->ext;
101 return true;
102 }
103 }
104
105 if (set->flags & NFT_SET_INTERVAL && interval != NULL &&
106 nft_set_elem_active(ext: &interval->ext, genmask) &&
107 !nft_rbtree_elem_expired(rbe: interval) &&
108 nft_rbtree_interval_start(rbe: interval)) {
109 *ext = &interval->ext;
110 return true;
111 }
112
113 return false;
114}
115
116INDIRECT_CALLABLE_SCOPE
117bool nft_rbtree_lookup(const struct net *net, const struct nft_set *set,
118 const u32 *key, const struct nft_set_ext **ext)
119{
120 struct nft_rbtree *priv = nft_set_priv(set);
121 unsigned int seq = read_seqcount_begin(&priv->count);
122 bool ret;
123
124 ret = __nft_rbtree_lookup(net, set, key, ext, seq);
125 if (ret || !read_seqcount_retry(&priv->count, seq))
126 return ret;
127
128 read_lock_bh(&priv->lock);
129 seq = read_seqcount_begin(&priv->count);
130 ret = __nft_rbtree_lookup(net, set, key, ext, seq);
131 read_unlock_bh(&priv->lock);
132
133 return ret;
134}
135
136static bool __nft_rbtree_get(const struct net *net, const struct nft_set *set,
137 const u32 *key, struct nft_rbtree_elem **elem,
138 unsigned int seq, unsigned int flags, u8 genmask)
139{
140 struct nft_rbtree_elem *rbe, *interval = NULL;
141 struct nft_rbtree *priv = nft_set_priv(set);
142 const struct rb_node *parent;
143 const void *this;
144 int d;
145
146 parent = rcu_dereference_raw(priv->root.rb_node);
147 while (parent != NULL) {
148 if (read_seqcount_retry(&priv->count, seq))
149 return false;
150
151 rbe = rb_entry(parent, struct nft_rbtree_elem, node);
152
153 this = nft_set_ext_key(ext: &rbe->ext);
154 d = memcmp(p: this, q: key, size: set->klen);
155 if (d < 0) {
156 parent = rcu_dereference_raw(parent->rb_left);
157 if (!(flags & NFT_SET_ELEM_INTERVAL_END))
158 interval = rbe;
159 } else if (d > 0) {
160 parent = rcu_dereference_raw(parent->rb_right);
161 if (flags & NFT_SET_ELEM_INTERVAL_END)
162 interval = rbe;
163 } else {
164 if (!nft_set_elem_active(ext: &rbe->ext, genmask)) {
165 parent = rcu_dereference_raw(parent->rb_left);
166 continue;
167 }
168
169 if (nft_set_elem_expired(ext: &rbe->ext))
170 return false;
171
172 if (!nft_set_ext_exists(ext: &rbe->ext, id: NFT_SET_EXT_FLAGS) ||
173 (*nft_set_ext_flags(ext: &rbe->ext) & NFT_SET_ELEM_INTERVAL_END) ==
174 (flags & NFT_SET_ELEM_INTERVAL_END)) {
175 *elem = rbe;
176 return true;
177 }
178
179 if (nft_rbtree_interval_end(rbe))
180 interval = NULL;
181
182 parent = rcu_dereference_raw(parent->rb_left);
183 }
184 }
185
186 if (set->flags & NFT_SET_INTERVAL && interval != NULL &&
187 nft_set_elem_active(ext: &interval->ext, genmask) &&
188 !nft_set_elem_expired(ext: &interval->ext) &&
189 ((!nft_rbtree_interval_end(rbe: interval) &&
190 !(flags & NFT_SET_ELEM_INTERVAL_END)) ||
191 (nft_rbtree_interval_end(rbe: interval) &&
192 (flags & NFT_SET_ELEM_INTERVAL_END)))) {
193 *elem = interval;
194 return true;
195 }
196
197 return false;
198}
199
200static struct nft_elem_priv *
201nft_rbtree_get(const struct net *net, const struct nft_set *set,
202 const struct nft_set_elem *elem, unsigned int flags)
203{
204 struct nft_rbtree *priv = nft_set_priv(set);
205 unsigned int seq = read_seqcount_begin(&priv->count);
206 struct nft_rbtree_elem *rbe = ERR_PTR(error: -ENOENT);
207 const u32 *key = (const u32 *)&elem->key.val;
208 u8 genmask = nft_genmask_cur(net);
209 bool ret;
210
211 ret = __nft_rbtree_get(net, set, key, elem: &rbe, seq, flags, genmask);
212 if (ret || !read_seqcount_retry(&priv->count, seq))
213 return &rbe->priv;
214
215 read_lock_bh(&priv->lock);
216 seq = read_seqcount_begin(&priv->count);
217 ret = __nft_rbtree_get(net, set, key, elem: &rbe, seq, flags, genmask);
218 read_unlock_bh(&priv->lock);
219
220 if (!ret)
221 return ERR_PTR(error: -ENOENT);
222
223 return &rbe->priv;
224}
225
226static void nft_rbtree_gc_elem_remove(struct net *net, struct nft_set *set,
227 struct nft_rbtree *priv,
228 struct nft_rbtree_elem *rbe)
229{
230 lockdep_assert_held_write(&priv->lock);
231 nft_setelem_data_deactivate(net, set, elem_priv: &rbe->priv);
232 rb_erase(&rbe->node, &priv->root);
233}
234
235static const struct nft_rbtree_elem *
236nft_rbtree_gc_elem(const struct nft_set *__set, struct nft_rbtree *priv,
237 struct nft_rbtree_elem *rbe, u8 genmask)
238{
239 struct nft_set *set = (struct nft_set *)__set;
240 struct rb_node *prev = rb_prev(&rbe->node);
241 struct net *net = read_pnet(pnet: &set->net);
242 struct nft_rbtree_elem *rbe_prev;
243 struct nft_trans_gc *gc;
244
245 gc = nft_trans_gc_alloc(set, gc_seq: 0, GFP_ATOMIC);
246 if (!gc)
247 return ERR_PTR(error: -ENOMEM);
248
249 /* search for end interval coming before this element.
250 * end intervals don't carry a timeout extension, they
251 * are coupled with the interval start element.
252 */
253 while (prev) {
254 rbe_prev = rb_entry(prev, struct nft_rbtree_elem, node);
255 if (nft_rbtree_interval_end(rbe: rbe_prev) &&
256 nft_set_elem_active(ext: &rbe_prev->ext, genmask))
257 break;
258
259 prev = rb_prev(prev);
260 }
261
262 rbe_prev = NULL;
263 if (prev) {
264 rbe_prev = rb_entry(prev, struct nft_rbtree_elem, node);
265 nft_rbtree_gc_elem_remove(net, set, priv, rbe: rbe_prev);
266
267 /* There is always room in this trans gc for this element,
268 * memory allocation never actually happens, hence, the warning
269 * splat in such case. No need to set NFT_SET_ELEM_DEAD_BIT,
270 * this is synchronous gc which never fails.
271 */
272 gc = nft_trans_gc_queue_sync(gc, GFP_ATOMIC);
273 if (WARN_ON_ONCE(!gc))
274 return ERR_PTR(error: -ENOMEM);
275
276 nft_trans_gc_elem_add(gc, priv: rbe_prev);
277 }
278
279 nft_rbtree_gc_elem_remove(net, set, priv, rbe);
280 gc = nft_trans_gc_queue_sync(gc, GFP_ATOMIC);
281 if (WARN_ON_ONCE(!gc))
282 return ERR_PTR(error: -ENOMEM);
283
284 nft_trans_gc_elem_add(gc, priv: rbe);
285
286 nft_trans_gc_queue_sync_done(trans: gc);
287
288 return rbe_prev;
289}
290
291static bool nft_rbtree_update_first(const struct nft_set *set,
292 struct nft_rbtree_elem *rbe,
293 struct rb_node *first)
294{
295 struct nft_rbtree_elem *first_elem;
296
297 first_elem = rb_entry(first, struct nft_rbtree_elem, node);
298 /* this element is closest to where the new element is to be inserted:
299 * update the first element for the node list path.
300 */
301 if (nft_rbtree_cmp(set, e1: rbe, e2: first_elem) < 0)
302 return true;
303
304 return false;
305}
306
307static int __nft_rbtree_insert(const struct net *net, const struct nft_set *set,
308 struct nft_rbtree_elem *new,
309 struct nft_elem_priv **elem_priv)
310{
311 struct nft_rbtree_elem *rbe, *rbe_le = NULL, *rbe_ge = NULL;
312 struct rb_node *node, *next, *parent, **p, *first = NULL;
313 struct nft_rbtree *priv = nft_set_priv(set);
314 u8 cur_genmask = nft_genmask_cur(net);
315 u8 genmask = nft_genmask_next(net);
316 int d;
317
318 /* Descend the tree to search for an existing element greater than the
319 * key value to insert that is greater than the new element. This is the
320 * first element to walk the ordered elements to find possible overlap.
321 */
322 parent = NULL;
323 p = &priv->root.rb_node;
324 while (*p != NULL) {
325 parent = *p;
326 rbe = rb_entry(parent, struct nft_rbtree_elem, node);
327 d = nft_rbtree_cmp(set, e1: rbe, e2: new);
328
329 if (d < 0) {
330 p = &parent->rb_left;
331 } else if (d > 0) {
332 if (!first ||
333 nft_rbtree_update_first(set, rbe, first))
334 first = &rbe->node;
335
336 p = &parent->rb_right;
337 } else {
338 if (nft_rbtree_interval_end(rbe))
339 p = &parent->rb_left;
340 else
341 p = &parent->rb_right;
342 }
343 }
344
345 if (!first)
346 first = rb_first(&priv->root);
347
348 /* Detect overlap by going through the list of valid tree nodes.
349 * Values stored in the tree are in reversed order, starting from
350 * highest to lowest value.
351 */
352 for (node = first; node != NULL; node = next) {
353 next = rb_next(node);
354
355 rbe = rb_entry(node, struct nft_rbtree_elem, node);
356
357 if (!nft_set_elem_active(ext: &rbe->ext, genmask))
358 continue;
359
360 /* perform garbage collection to avoid bogus overlap reports
361 * but skip new elements in this transaction.
362 */
363 if (nft_set_elem_expired(ext: &rbe->ext) &&
364 nft_set_elem_active(ext: &rbe->ext, genmask: cur_genmask)) {
365 const struct nft_rbtree_elem *removed_end;
366
367 removed_end = nft_rbtree_gc_elem(set: set, priv, rbe, genmask);
368 if (IS_ERR(ptr: removed_end))
369 return PTR_ERR(ptr: removed_end);
370
371 if (removed_end == rbe_le || removed_end == rbe_ge)
372 return -EAGAIN;
373
374 continue;
375 }
376
377 d = nft_rbtree_cmp(set, e1: rbe, e2: new);
378 if (d == 0) {
379 /* Matching end element: no need to look for an
380 * overlapping greater or equal element.
381 */
382 if (nft_rbtree_interval_end(rbe)) {
383 rbe_le = rbe;
384 break;
385 }
386
387 /* first element that is greater or equal to key value. */
388 if (!rbe_ge) {
389 rbe_ge = rbe;
390 continue;
391 }
392
393 /* this is a closer more or equal element, update it. */
394 if (nft_rbtree_cmp(set, e1: rbe_ge, e2: new) != 0) {
395 rbe_ge = rbe;
396 continue;
397 }
398
399 /* element is equal to key value, make sure flags are
400 * the same, an existing more or equal start element
401 * must not be replaced by more or equal end element.
402 */
403 if ((nft_rbtree_interval_start(rbe: new) &&
404 nft_rbtree_interval_start(rbe: rbe_ge)) ||
405 (nft_rbtree_interval_end(rbe: new) &&
406 nft_rbtree_interval_end(rbe: rbe_ge))) {
407 rbe_ge = rbe;
408 continue;
409 }
410 } else if (d > 0) {
411 /* annotate element greater than the new element. */
412 rbe_ge = rbe;
413 continue;
414 } else if (d < 0) {
415 /* annotate element less than the new element. */
416 rbe_le = rbe;
417 break;
418 }
419 }
420
421 /* - new start element matching existing start element: full overlap
422 * reported as -EEXIST, cleared by caller if NLM_F_EXCL is not given.
423 */
424 if (rbe_ge && !nft_rbtree_cmp(set, e1: new, e2: rbe_ge) &&
425 nft_rbtree_interval_start(rbe: rbe_ge) == nft_rbtree_interval_start(rbe: new)) {
426 *elem_priv = &rbe_ge->priv;
427 return -EEXIST;
428 }
429
430 /* - new end element matching existing end element: full overlap
431 * reported as -EEXIST, cleared by caller if NLM_F_EXCL is not given.
432 */
433 if (rbe_le && !nft_rbtree_cmp(set, e1: new, e2: rbe_le) &&
434 nft_rbtree_interval_end(rbe: rbe_le) == nft_rbtree_interval_end(rbe: new)) {
435 *elem_priv = &rbe_le->priv;
436 return -EEXIST;
437 }
438
439 /* - new start element with existing closest, less or equal key value
440 * being a start element: partial overlap, reported as -ENOTEMPTY.
441 * Anonymous sets allow for two consecutive start element since they
442 * are constant, skip them to avoid bogus overlap reports.
443 */
444 if (!nft_set_is_anonymous(set) && rbe_le &&
445 nft_rbtree_interval_start(rbe: rbe_le) && nft_rbtree_interval_start(rbe: new))
446 return -ENOTEMPTY;
447
448 /* - new end element with existing closest, less or equal key value
449 * being a end element: partial overlap, reported as -ENOTEMPTY.
450 */
451 if (rbe_le &&
452 nft_rbtree_interval_end(rbe: rbe_le) && nft_rbtree_interval_end(rbe: new))
453 return -ENOTEMPTY;
454
455 /* - new end element with existing closest, greater or equal key value
456 * being an end element: partial overlap, reported as -ENOTEMPTY
457 */
458 if (rbe_ge &&
459 nft_rbtree_interval_end(rbe: rbe_ge) && nft_rbtree_interval_end(rbe: new))
460 return -ENOTEMPTY;
461
462 /* Accepted element: pick insertion point depending on key value */
463 parent = NULL;
464 p = &priv->root.rb_node;
465 while (*p != NULL) {
466 parent = *p;
467 rbe = rb_entry(parent, struct nft_rbtree_elem, node);
468 d = nft_rbtree_cmp(set, e1: rbe, e2: new);
469
470 if (d < 0)
471 p = &parent->rb_left;
472 else if (d > 0)
473 p = &parent->rb_right;
474 else if (nft_rbtree_interval_end(rbe))
475 p = &parent->rb_left;
476 else
477 p = &parent->rb_right;
478 }
479
480 rb_link_node_rcu(node: &new->node, parent, rb_link: p);
481 rb_insert_color(&new->node, &priv->root);
482 return 0;
483}
484
485static int nft_rbtree_insert(const struct net *net, const struct nft_set *set,
486 const struct nft_set_elem *elem,
487 struct nft_elem_priv **elem_priv)
488{
489 struct nft_rbtree_elem *rbe = nft_elem_priv_cast(priv: elem->priv);
490 struct nft_rbtree *priv = nft_set_priv(set);
491 int err;
492
493 do {
494 if (fatal_signal_pending(current))
495 return -EINTR;
496
497 cond_resched();
498
499 write_lock_bh(&priv->lock);
500 write_seqcount_begin(&priv->count);
501 err = __nft_rbtree_insert(net, set, new: rbe, elem_priv);
502 write_seqcount_end(&priv->count);
503 write_unlock_bh(&priv->lock);
504 } while (err == -EAGAIN);
505
506 return err;
507}
508
509static void nft_rbtree_erase(struct nft_rbtree *priv, struct nft_rbtree_elem *rbe)
510{
511 write_lock_bh(&priv->lock);
512 write_seqcount_begin(&priv->count);
513 rb_erase(&rbe->node, &priv->root);
514 write_seqcount_end(&priv->count);
515 write_unlock_bh(&priv->lock);
516}
517
518static void nft_rbtree_remove(const struct net *net,
519 const struct nft_set *set,
520 struct nft_elem_priv *elem_priv)
521{
522 struct nft_rbtree_elem *rbe = nft_elem_priv_cast(priv: elem_priv);
523 struct nft_rbtree *priv = nft_set_priv(set);
524
525 nft_rbtree_erase(priv, rbe);
526}
527
528static void nft_rbtree_activate(const struct net *net,
529 const struct nft_set *set,
530 struct nft_elem_priv *elem_priv)
531{
532 struct nft_rbtree_elem *rbe = nft_elem_priv_cast(priv: elem_priv);
533
534 nft_set_elem_change_active(net, set, ext: &rbe->ext);
535}
536
537static void nft_rbtree_flush(const struct net *net,
538 const struct nft_set *set,
539 struct nft_elem_priv *elem_priv)
540{
541 struct nft_rbtree_elem *rbe = nft_elem_priv_cast(priv: elem_priv);
542
543 nft_set_elem_change_active(net, set, ext: &rbe->ext);
544}
545
546static struct nft_elem_priv *
547nft_rbtree_deactivate(const struct net *net, const struct nft_set *set,
548 const struct nft_set_elem *elem)
549{
550 struct nft_rbtree_elem *rbe, *this = nft_elem_priv_cast(priv: elem->priv);
551 const struct nft_rbtree *priv = nft_set_priv(set);
552 const struct rb_node *parent = priv->root.rb_node;
553 u8 genmask = nft_genmask_next(net);
554 int d;
555
556 while (parent != NULL) {
557 rbe = rb_entry(parent, struct nft_rbtree_elem, node);
558
559 d = memcmp(p: nft_set_ext_key(ext: &rbe->ext), q: &elem->key.val,
560 size: set->klen);
561 if (d < 0)
562 parent = parent->rb_left;
563 else if (d > 0)
564 parent = parent->rb_right;
565 else {
566 if (nft_rbtree_interval_end(rbe) &&
567 nft_rbtree_interval_start(rbe: this)) {
568 parent = parent->rb_left;
569 continue;
570 } else if (nft_rbtree_interval_start(rbe) &&
571 nft_rbtree_interval_end(rbe: this)) {
572 parent = parent->rb_right;
573 continue;
574 } else if (nft_set_elem_expired(ext: &rbe->ext)) {
575 break;
576 } else if (!nft_set_elem_active(ext: &rbe->ext, genmask)) {
577 parent = parent->rb_left;
578 continue;
579 }
580 nft_rbtree_flush(net, set, elem_priv: &rbe->priv);
581 return &rbe->priv;
582 }
583 }
584 return NULL;
585}
586
587static void nft_rbtree_walk(const struct nft_ctx *ctx,
588 struct nft_set *set,
589 struct nft_set_iter *iter)
590{
591 struct nft_rbtree *priv = nft_set_priv(set);
592 struct nft_rbtree_elem *rbe;
593 struct rb_node *node;
594
595 read_lock_bh(&priv->lock);
596 for (node = rb_first(&priv->root); node != NULL; node = rb_next(node)) {
597 rbe = rb_entry(node, struct nft_rbtree_elem, node);
598
599 if (iter->count < iter->skip)
600 goto cont;
601 if (!nft_set_elem_active(ext: &rbe->ext, genmask: iter->genmask))
602 goto cont;
603
604 iter->err = iter->fn(ctx, set, iter, &rbe->priv);
605 if (iter->err < 0) {
606 read_unlock_bh(&priv->lock);
607 return;
608 }
609cont:
610 iter->count++;
611 }
612 read_unlock_bh(&priv->lock);
613}
614
615static void nft_rbtree_gc_remove(struct net *net, struct nft_set *set,
616 struct nft_rbtree *priv,
617 struct nft_rbtree_elem *rbe)
618{
619 nft_setelem_data_deactivate(net, set, elem_priv: &rbe->priv);
620 nft_rbtree_erase(priv, rbe);
621}
622
623static void nft_rbtree_gc(struct nft_set *set)
624{
625 struct nft_rbtree *priv = nft_set_priv(set);
626 struct nft_rbtree_elem *rbe, *rbe_end = NULL;
627 struct nftables_pernet *nft_net;
628 struct rb_node *node, *next;
629 struct nft_trans_gc *gc;
630 struct net *net;
631
632 set = nft_set_container_of(priv);
633 net = read_pnet(pnet: &set->net);
634 nft_net = nft_pernet(net);
635
636 gc = nft_trans_gc_alloc(set, gc_seq: 0, GFP_KERNEL);
637 if (!gc)
638 return;
639
640 for (node = rb_first(&priv->root); node ; node = next) {
641 next = rb_next(node);
642
643 rbe = rb_entry(node, struct nft_rbtree_elem, node);
644
645 /* elements are reversed in the rbtree for historical reasons,
646 * from highest to lowest value, that is why end element is
647 * always visited before the start element.
648 */
649 if (nft_rbtree_interval_end(rbe)) {
650 rbe_end = rbe;
651 continue;
652 }
653 if (!nft_set_elem_expired(ext: &rbe->ext))
654 continue;
655
656 gc = nft_trans_gc_queue_sync(gc, GFP_KERNEL);
657 if (!gc)
658 goto try_later;
659
660 /* end element needs to be removed first, it has
661 * no timeout extension.
662 */
663 if (rbe_end) {
664 nft_rbtree_gc_remove(net, set, priv, rbe: rbe_end);
665 nft_trans_gc_elem_add(gc, priv: rbe_end);
666 rbe_end = NULL;
667 }
668
669 gc = nft_trans_gc_queue_sync(gc, GFP_KERNEL);
670 if (!gc)
671 goto try_later;
672
673 nft_rbtree_gc_remove(net, set, priv, rbe);
674 nft_trans_gc_elem_add(gc, priv: rbe);
675 }
676
677try_later:
678
679 if (gc) {
680 gc = nft_trans_gc_catchall_sync(gc);
681 nft_trans_gc_queue_sync_done(trans: gc);
682 priv->last_gc = jiffies;
683 }
684}
685
686static u64 nft_rbtree_privsize(const struct nlattr * const nla[],
687 const struct nft_set_desc *desc)
688{
689 return sizeof(struct nft_rbtree);
690}
691
692static int nft_rbtree_init(const struct nft_set *set,
693 const struct nft_set_desc *desc,
694 const struct nlattr * const nla[])
695{
696 struct nft_rbtree *priv = nft_set_priv(set);
697
698 BUILD_BUG_ON(offsetof(struct nft_rbtree_elem, priv) != 0);
699
700 rwlock_init(&priv->lock);
701 seqcount_rwlock_init(&priv->count, &priv->lock);
702 priv->root = RB_ROOT;
703
704 return 0;
705}
706
707static void nft_rbtree_destroy(const struct nft_ctx *ctx,
708 const struct nft_set *set)
709{
710 struct nft_rbtree *priv = nft_set_priv(set);
711 struct nft_rbtree_elem *rbe;
712 struct rb_node *node;
713
714 while ((node = priv->root.rb_node) != NULL) {
715 rb_erase(node, &priv->root);
716 rbe = rb_entry(node, struct nft_rbtree_elem, node);
717 nf_tables_set_elem_destroy(ctx, set, elem_priv: &rbe->priv);
718 }
719}
720
721static bool nft_rbtree_estimate(const struct nft_set_desc *desc, u32 features,
722 struct nft_set_estimate *est)
723{
724 if (desc->field_count > 1)
725 return false;
726
727 if (desc->size)
728 est->size = sizeof(struct nft_rbtree) +
729 desc->size * sizeof(struct nft_rbtree_elem);
730 else
731 est->size = ~0;
732
733 est->lookup = NFT_SET_CLASS_O_LOG_N;
734 est->space = NFT_SET_CLASS_O_N;
735
736 return true;
737}
738
739static void nft_rbtree_commit(struct nft_set *set)
740{
741 struct nft_rbtree *priv = nft_set_priv(set);
742
743 if (time_after_eq(jiffies, priv->last_gc + nft_set_gc_interval(set)))
744 nft_rbtree_gc(set);
745}
746
747static void nft_rbtree_gc_init(const struct nft_set *set)
748{
749 struct nft_rbtree *priv = nft_set_priv(set);
750
751 priv->last_gc = jiffies;
752}
753
754const struct nft_set_type nft_set_rbtree_type = {
755 .features = NFT_SET_INTERVAL | NFT_SET_MAP | NFT_SET_OBJECT | NFT_SET_TIMEOUT,
756 .ops = {
757 .privsize = nft_rbtree_privsize,
758 .elemsize = offsetof(struct nft_rbtree_elem, ext),
759 .estimate = nft_rbtree_estimate,
760 .init = nft_rbtree_init,
761 .destroy = nft_rbtree_destroy,
762 .insert = nft_rbtree_insert,
763 .remove = nft_rbtree_remove,
764 .deactivate = nft_rbtree_deactivate,
765 .flush = nft_rbtree_flush,
766 .activate = nft_rbtree_activate,
767 .commit = nft_rbtree_commit,
768 .gc_init = nft_rbtree_gc_init,
769 .lookup = nft_rbtree_lookup,
770 .walk = nft_rbtree_walk,
771 .get = nft_rbtree_get,
772 },
773};
774

source code of linux/net/netfilter/nft_set_rbtree.c