1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (c) 2008-2014 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/log2.h>
13#include <linux/jhash.h>
14#include <linux/netlink.h>
15#include <linux/workqueue.h>
16#include <linux/rhashtable.h>
17#include <linux/netfilter.h>
18#include <linux/netfilter/nf_tables.h>
19#include <net/netfilter/nf_tables_core.h>
20
21/* We target a hash table size of 4, element hint is 75% of final size */
22#define NFT_RHASH_ELEMENT_HINT 3
23
24struct nft_rhash {
25 struct rhashtable ht;
26 struct delayed_work gc_work;
27 u32 wq_gc_seq;
28};
29
30struct nft_rhash_elem {
31 struct nft_elem_priv priv;
32 struct rhash_head node;
33 struct llist_node walk_node;
34 u32 wq_gc_seq;
35 struct nft_set_ext ext;
36};
37
38struct nft_rhash_cmp_arg {
39 const struct nft_set *set;
40 const u32 *key;
41 u8 genmask;
42 u64 tstamp;
43};
44
45static inline u32 nft_rhash_key(const void *data, u32 len, u32 seed)
46{
47 const struct nft_rhash_cmp_arg *arg = data;
48
49 return jhash(key: arg->key, length: len, initval: seed);
50}
51
52static inline u32 nft_rhash_obj(const void *data, u32 len, u32 seed)
53{
54 const struct nft_rhash_elem *he = data;
55
56 return jhash(key: nft_set_ext_key(ext: &he->ext), length: len, initval: seed);
57}
58
59static inline int nft_rhash_cmp(struct rhashtable_compare_arg *arg,
60 const void *ptr)
61{
62 const struct nft_rhash_cmp_arg *x = arg->key;
63 const struct nft_rhash_elem *he = ptr;
64
65 if (memcmp(p: nft_set_ext_key(ext: &he->ext), q: x->key, size: x->set->klen))
66 return 1;
67 if (nft_set_elem_is_dead(ext: &he->ext))
68 return 1;
69 if (__nft_set_elem_expired(ext: &he->ext, tstamp: x->tstamp))
70 return 1;
71 if (!nft_set_elem_active(ext: &he->ext, genmask: x->genmask))
72 return 1;
73 return 0;
74}
75
76static const struct rhashtable_params nft_rhash_params = {
77 .head_offset = offsetof(struct nft_rhash_elem, node),
78 .hashfn = nft_rhash_key,
79 .obj_hashfn = nft_rhash_obj,
80 .obj_cmpfn = nft_rhash_cmp,
81 .automatic_shrinking = true,
82};
83
84INDIRECT_CALLABLE_SCOPE
85const struct nft_set_ext *
86nft_rhash_lookup(const struct net *net, const struct nft_set *set,
87 const u32 *key)
88{
89 struct nft_rhash *priv = nft_set_priv(set);
90 const struct nft_rhash_elem *he;
91 struct nft_rhash_cmp_arg arg = {
92 .genmask = nft_genmask_cur(net),
93 .set = set,
94 .key = key,
95 .tstamp = get_jiffies_64(),
96 };
97
98 he = rhashtable_lookup(ht: &priv->ht, key: &arg, params: nft_rhash_params);
99 if (he != NULL)
100 return &he->ext;
101
102 return NULL;
103}
104
105static struct nft_elem_priv *
106nft_rhash_get(const struct net *net, const struct nft_set *set,
107 const struct nft_set_elem *elem, unsigned int flags)
108{
109 struct nft_rhash *priv = nft_set_priv(set);
110 struct nft_rhash_elem *he;
111 struct nft_rhash_cmp_arg arg = {
112 .genmask = nft_genmask_cur(net),
113 .set = set,
114 .key = elem->key.val.data,
115 .tstamp = get_jiffies_64(),
116 };
117
118 he = rhashtable_lookup(ht: &priv->ht, key: &arg, params: nft_rhash_params);
119 if (he != NULL)
120 return &he->priv;
121
122 return ERR_PTR(error: -ENOENT);
123}
124
125static const struct nft_set_ext *
126nft_rhash_update(struct nft_set *set, const u32 *key,
127 const struct nft_expr *expr, struct nft_regs *regs)
128{
129 struct nft_rhash *priv = nft_set_priv(set);
130 struct nft_rhash_elem *he, *prev;
131 struct nft_elem_priv *elem_priv;
132 struct nft_rhash_cmp_arg arg = {
133 .genmask = NFT_GENMASK_ANY,
134 .set = set,
135 .key = key,
136 .tstamp = get_jiffies_64(),
137 };
138
139 he = rhashtable_lookup(ht: &priv->ht, key: &arg, params: nft_rhash_params);
140 if (he != NULL)
141 goto out;
142
143 elem_priv = nft_dynset_new(set, expr, regs);
144 if (!elem_priv)
145 goto err1;
146
147 he = nft_elem_priv_cast(priv: elem_priv);
148 init_llist_node(node: &he->walk_node);
149 prev = rhashtable_lookup_get_insert_key(ht: &priv->ht, key: &arg, obj: &he->node,
150 params: nft_rhash_params);
151 if (IS_ERR(ptr: prev))
152 goto err2;
153
154 /* Another cpu may race to insert the element with the same key */
155 if (prev) {
156 nft_set_elem_destroy(set, elem_priv: &he->priv, destroy_expr: true);
157 atomic_dec(v: &set->nelems);
158 he = prev;
159 }
160
161out:
162 return &he->ext;
163
164err2:
165 nft_set_elem_destroy(set, elem_priv: &he->priv, destroy_expr: true);
166 atomic_dec(v: &set->nelems);
167err1:
168 return NULL;
169}
170
171static int nft_rhash_insert(const struct net *net, const struct nft_set *set,
172 const struct nft_set_elem *elem,
173 struct nft_elem_priv **elem_priv)
174{
175 struct nft_rhash_elem *he = nft_elem_priv_cast(priv: elem->priv);
176 struct nft_rhash *priv = nft_set_priv(set);
177 struct nft_rhash_cmp_arg arg = {
178 .genmask = nft_genmask_next(net),
179 .set = set,
180 .key = elem->key.val.data,
181 .tstamp = nft_net_tstamp(net),
182 };
183 struct nft_rhash_elem *prev;
184
185 init_llist_node(node: &he->walk_node);
186 prev = rhashtable_lookup_get_insert_key(ht: &priv->ht, key: &arg, obj: &he->node,
187 params: nft_rhash_params);
188 if (IS_ERR(ptr: prev))
189 return PTR_ERR(ptr: prev);
190 if (prev) {
191 *elem_priv = &prev->priv;
192 return -EEXIST;
193 }
194 return 0;
195}
196
197static void nft_rhash_activate(const struct net *net, const struct nft_set *set,
198 struct nft_elem_priv *elem_priv)
199{
200 struct nft_rhash_elem *he = nft_elem_priv_cast(priv: elem_priv);
201
202 nft_clear(net, &he->ext);
203}
204
205static void nft_rhash_flush(const struct net *net,
206 const struct nft_set *set,
207 struct nft_elem_priv *elem_priv)
208{
209 struct nft_rhash_elem *he = nft_elem_priv_cast(priv: elem_priv);
210
211 nft_set_elem_change_active(net, set, ext: &he->ext);
212}
213
214static struct nft_elem_priv *
215nft_rhash_deactivate(const struct net *net, const struct nft_set *set,
216 const struct nft_set_elem *elem)
217{
218 struct nft_rhash *priv = nft_set_priv(set);
219 struct nft_rhash_elem *he;
220 struct nft_rhash_cmp_arg arg = {
221 .genmask = nft_genmask_next(net),
222 .set = set,
223 .key = elem->key.val.data,
224 .tstamp = nft_net_tstamp(net),
225 };
226
227 rcu_read_lock();
228 he = rhashtable_lookup(ht: &priv->ht, key: &arg, params: nft_rhash_params);
229 if (he)
230 nft_set_elem_change_active(net, set, ext: &he->ext);
231
232 rcu_read_unlock();
233
234 return &he->priv;
235}
236
237static void nft_rhash_remove(const struct net *net,
238 const struct nft_set *set,
239 struct nft_elem_priv *elem_priv)
240{
241 struct nft_rhash_elem *he = nft_elem_priv_cast(priv: elem_priv);
242 struct nft_rhash *priv = nft_set_priv(set);
243
244 rhashtable_remove_fast(ht: &priv->ht, obj: &he->node, params: nft_rhash_params);
245}
246
247static bool nft_rhash_delete(const struct nft_set *set,
248 const u32 *key)
249{
250 struct nft_rhash *priv = nft_set_priv(set);
251 struct nft_rhash_cmp_arg arg = {
252 .genmask = NFT_GENMASK_ANY,
253 .set = set,
254 .key = key,
255 };
256 struct nft_rhash_elem *he;
257
258 he = rhashtable_lookup(ht: &priv->ht, key: &arg, params: nft_rhash_params);
259 if (he == NULL)
260 return false;
261
262 nft_set_elem_dead(ext: &he->ext);
263
264 return true;
265}
266
267static void nft_rhash_walk_ro(const struct nft_ctx *ctx, struct nft_set *set,
268 struct nft_set_iter *iter)
269{
270 struct nft_rhash *priv = nft_set_priv(set);
271 struct rhashtable_iter hti;
272 struct nft_rhash_elem *he;
273
274 rhashtable_walk_enter(ht: &priv->ht, iter: &hti);
275 rhashtable_walk_start(iter: &hti);
276
277 while ((he = rhashtable_walk_next(iter: &hti))) {
278 if (IS_ERR(ptr: he)) {
279 if (PTR_ERR(ptr: he) != -EAGAIN) {
280 iter->err = PTR_ERR(ptr: he);
281 break;
282 }
283
284 continue;
285 }
286
287 if (iter->count < iter->skip)
288 goto cont;
289
290 iter->err = iter->fn(ctx, set, iter, &he->priv);
291 if (iter->err < 0)
292 break;
293
294cont:
295 iter->count++;
296 }
297 rhashtable_walk_stop(iter: &hti);
298 rhashtable_walk_exit(iter: &hti);
299}
300
301static void nft_rhash_walk_update(const struct nft_ctx *ctx,
302 struct nft_set *set,
303 struct nft_set_iter *iter)
304{
305 struct nft_rhash *priv = nft_set_priv(set);
306 struct nft_rhash_elem *he, *tmp;
307 struct llist_node *first_node;
308 struct rhashtable_iter hti;
309 LLIST_HEAD(walk_list);
310
311 lockdep_assert_held(&nft_pernet(ctx->net)->commit_mutex);
312
313 if (set->in_update_walk) {
314 /* This can happen with bogus rulesets during ruleset validation
315 * when a verdict map causes a jump back to the same map.
316 *
317 * Without this extra check the walk_next loop below will see
318 * elems on the callers walk_list and skip (not validate) them.
319 */
320 iter->err = -EMLINK;
321 return;
322 }
323
324 /* walk happens under RCU.
325 *
326 * We create a snapshot list so ->iter callback can sleep.
327 * commit_mutex is held, elements can ...
328 * .. be added in parallel from dataplane (dynset)
329 * .. be marked as dead in parallel from dataplane (dynset).
330 * .. be queued for removal in parallel (gc timeout).
331 * .. not be freed: transaction mutex is held.
332 */
333 rhashtable_walk_enter(ht: &priv->ht, iter: &hti);
334 rhashtable_walk_start(iter: &hti);
335
336 while ((he = rhashtable_walk_next(iter: &hti))) {
337 if (IS_ERR(ptr: he)) {
338 if (PTR_ERR(ptr: he) != -EAGAIN) {
339 iter->err = PTR_ERR(ptr: he);
340 break;
341 }
342
343 continue;
344 }
345
346 /* rhashtable resized during walk, skip */
347 if (llist_on_list(node: &he->walk_node))
348 continue;
349
350 llist_add(new: &he->walk_node, head: &walk_list);
351 }
352 rhashtable_walk_stop(iter: &hti);
353 rhashtable_walk_exit(iter: &hti);
354
355 first_node = __llist_del_all(head: &walk_list);
356 set->in_update_walk = true;
357 llist_for_each_entry_safe(he, tmp, first_node, walk_node) {
358 if (iter->err == 0) {
359 iter->err = iter->fn(ctx, set, iter, &he->priv);
360 if (iter->err == 0)
361 iter->count++;
362 }
363
364 /* all entries must be cleared again, else next ->walk iteration
365 * will skip entries.
366 */
367 init_llist_node(node: &he->walk_node);
368 }
369 set->in_update_walk = false;
370}
371
372static void nft_rhash_walk(const struct nft_ctx *ctx, struct nft_set *set,
373 struct nft_set_iter *iter)
374{
375 switch (iter->type) {
376 case NFT_ITER_UPDATE:
377 /* only relevant for netlink dumps which use READ type */
378 WARN_ON_ONCE(iter->skip != 0);
379
380 nft_rhash_walk_update(ctx, set, iter);
381 break;
382 case NFT_ITER_READ:
383 nft_rhash_walk_ro(ctx, set, iter);
384 break;
385 default:
386 iter->err = -EINVAL;
387 WARN_ON_ONCE(1);
388 break;
389 }
390}
391
392static bool nft_rhash_expr_needs_gc_run(const struct nft_set *set,
393 struct nft_set_ext *ext)
394{
395 struct nft_set_elem_expr *elem_expr = nft_set_ext_expr(ext);
396 struct nft_expr *expr;
397 u32 size;
398
399 nft_setelem_expr_foreach(expr, elem_expr, size) {
400 if (expr->ops->gc &&
401 expr->ops->gc(read_pnet(pnet: &set->net), expr) &&
402 set->flags & NFT_SET_EVAL)
403 return true;
404 }
405
406 return false;
407}
408
409static void nft_rhash_gc(struct work_struct *work)
410{
411 struct nftables_pernet *nft_net;
412 struct nft_set *set;
413 struct nft_rhash_elem *he;
414 struct nft_rhash *priv;
415 struct rhashtable_iter hti;
416 struct nft_trans_gc *gc;
417 struct net *net;
418 u32 gc_seq;
419
420 priv = container_of(work, struct nft_rhash, gc_work.work);
421 set = nft_set_container_of(priv);
422 net = read_pnet(pnet: &set->net);
423 nft_net = nft_pernet(net);
424 gc_seq = READ_ONCE(nft_net->gc_seq);
425
426 if (nft_set_gc_is_pending(s: set))
427 goto done;
428
429 gc = nft_trans_gc_alloc(set, gc_seq, GFP_KERNEL);
430 if (!gc)
431 goto done;
432
433 /* Elements never collected use a zero gc worker sequence number. */
434 if (unlikely(++priv->wq_gc_seq == 0))
435 priv->wq_gc_seq++;
436
437 rhashtable_walk_enter(ht: &priv->ht, iter: &hti);
438 rhashtable_walk_start(iter: &hti);
439
440 while ((he = rhashtable_walk_next(iter: &hti))) {
441 if (IS_ERR(ptr: he)) {
442 nft_trans_gc_destroy(trans: gc);
443 gc = NULL;
444 goto try_later;
445 }
446
447 /* Ruleset has been updated, try later. */
448 if (READ_ONCE(nft_net->gc_seq) != gc_seq) {
449 nft_trans_gc_destroy(trans: gc);
450 gc = NULL;
451 goto try_later;
452 }
453
454 /* rhashtable walk is unstable, already seen in this gc run?
455 * Then, skip this element. In case of (unlikely) sequence
456 * wraparound and stale element wq_gc_seq, next gc run will
457 * just find this expired element.
458 */
459 if (he->wq_gc_seq == priv->wq_gc_seq)
460 continue;
461
462 if (nft_set_elem_is_dead(ext: &he->ext))
463 goto dead_elem;
464
465 if (nft_set_ext_exists(ext: &he->ext, id: NFT_SET_EXT_EXPRESSIONS) &&
466 nft_rhash_expr_needs_gc_run(set, ext: &he->ext))
467 goto needs_gc_run;
468
469 if (!nft_set_elem_expired(ext: &he->ext))
470 continue;
471needs_gc_run:
472 nft_set_elem_dead(ext: &he->ext);
473dead_elem:
474 gc = nft_trans_gc_queue_async(gc, gc_seq, GFP_ATOMIC);
475 if (!gc)
476 goto try_later;
477
478 /* annotate gc sequence for this attempt. */
479 he->wq_gc_seq = priv->wq_gc_seq;
480 nft_trans_gc_elem_add(gc, priv: he);
481 }
482
483 gc = nft_trans_gc_catchall_async(gc, gc_seq);
484
485try_later:
486 /* catchall list iteration requires rcu read side lock. */
487 rhashtable_walk_stop(iter: &hti);
488 rhashtable_walk_exit(iter: &hti);
489
490 if (gc)
491 nft_trans_gc_queue_async_done(gc);
492
493done:
494 queue_delayed_work(wq: system_power_efficient_wq, dwork: &priv->gc_work,
495 delay: nft_set_gc_interval(set));
496}
497
498static u64 nft_rhash_privsize(const struct nlattr * const nla[],
499 const struct nft_set_desc *desc)
500{
501 return sizeof(struct nft_rhash);
502}
503
504static void nft_rhash_gc_init(const struct nft_set *set)
505{
506 struct nft_rhash *priv = nft_set_priv(set);
507
508 queue_delayed_work(wq: system_power_efficient_wq, dwork: &priv->gc_work,
509 delay: nft_set_gc_interval(set));
510}
511
512static int nft_rhash_init(const struct nft_set *set,
513 const struct nft_set_desc *desc,
514 const struct nlattr * const tb[])
515{
516 struct nft_rhash *priv = nft_set_priv(set);
517 struct rhashtable_params params = nft_rhash_params;
518 int err;
519
520 BUILD_BUG_ON(offsetof(struct nft_rhash_elem, priv) != 0);
521
522 params.nelem_hint = desc->size ?: NFT_RHASH_ELEMENT_HINT;
523 params.key_len = set->klen;
524
525 err = rhashtable_init(&priv->ht, &params);
526 if (err < 0)
527 return err;
528
529 INIT_DEFERRABLE_WORK(&priv->gc_work, nft_rhash_gc);
530 if (set->flags & (NFT_SET_TIMEOUT | NFT_SET_EVAL))
531 nft_rhash_gc_init(set);
532
533 return 0;
534}
535
536struct nft_rhash_ctx {
537 const struct nft_ctx ctx;
538 const struct nft_set *set;
539};
540
541static void nft_rhash_elem_destroy(void *ptr, void *arg)
542{
543 struct nft_rhash_ctx *rhash_ctx = arg;
544 struct nft_rhash_elem *he = ptr;
545
546 nf_tables_set_elem_destroy(ctx: &rhash_ctx->ctx, set: rhash_ctx->set, elem_priv: &he->priv);
547}
548
549static void nft_rhash_destroy(const struct nft_ctx *ctx,
550 const struct nft_set *set)
551{
552 struct nft_rhash *priv = nft_set_priv(set);
553 struct nft_rhash_ctx rhash_ctx = {
554 .ctx = *ctx,
555 .set = set,
556 };
557
558 cancel_delayed_work_sync(dwork: &priv->gc_work);
559 rhashtable_free_and_destroy(ht: &priv->ht, free_fn: nft_rhash_elem_destroy,
560 arg: (void *)&rhash_ctx);
561}
562
563/* Number of buckets is stored in u32, so cap our result to 1U<<31 */
564#define NFT_MAX_BUCKETS (1U << 31)
565
566static u32 nft_hash_buckets(u32 size)
567{
568 u64 val = div_u64(dividend: (u64)size * 4, divisor: 3);
569
570 if (val >= NFT_MAX_BUCKETS)
571 return NFT_MAX_BUCKETS;
572
573 return roundup_pow_of_two(val);
574}
575
576static bool nft_rhash_estimate(const struct nft_set_desc *desc, u32 features,
577 struct nft_set_estimate *est)
578{
579 est->size = ~0;
580 est->lookup = NFT_SET_CLASS_O_1;
581 est->space = NFT_SET_CLASS_O_N;
582
583 return true;
584}
585
586struct nft_hash {
587 u32 seed;
588 u32 buckets;
589 struct hlist_head table[];
590};
591
592struct nft_hash_elem {
593 struct nft_elem_priv priv;
594 struct hlist_node node;
595 struct nft_set_ext ext;
596};
597
598INDIRECT_CALLABLE_SCOPE
599const struct nft_set_ext *
600nft_hash_lookup(const struct net *net, const struct nft_set *set,
601 const u32 *key)
602{
603 struct nft_hash *priv = nft_set_priv(set);
604 u8 genmask = nft_genmask_cur(net);
605 const struct nft_hash_elem *he;
606 u32 hash;
607
608 hash = jhash(key, length: set->klen, initval: priv->seed);
609 hash = reciprocal_scale(val: hash, ep_ro: priv->buckets);
610 hlist_for_each_entry_rcu(he, &priv->table[hash], node) {
611 if (!memcmp(p: nft_set_ext_key(ext: &he->ext), q: key, size: set->klen) &&
612 nft_set_elem_active(ext: &he->ext, genmask))
613 return &he->ext;
614 }
615 return NULL;
616}
617
618static struct nft_elem_priv *
619nft_hash_get(const struct net *net, const struct nft_set *set,
620 const struct nft_set_elem *elem, unsigned int flags)
621{
622 struct nft_hash *priv = nft_set_priv(set);
623 u8 genmask = nft_genmask_cur(net);
624 struct nft_hash_elem *he;
625 u32 hash;
626
627 hash = jhash(key: elem->key.val.data, length: set->klen, initval: priv->seed);
628 hash = reciprocal_scale(val: hash, ep_ro: priv->buckets);
629 hlist_for_each_entry_rcu(he, &priv->table[hash], node) {
630 if (!memcmp(p: nft_set_ext_key(ext: &he->ext), q: elem->key.val.data, size: set->klen) &&
631 nft_set_elem_active(ext: &he->ext, genmask))
632 return &he->priv;
633 }
634 return ERR_PTR(error: -ENOENT);
635}
636
637INDIRECT_CALLABLE_SCOPE
638const struct nft_set_ext *
639nft_hash_lookup_fast(const struct net *net, const struct nft_set *set,
640 const u32 *key)
641{
642 struct nft_hash *priv = nft_set_priv(set);
643 u8 genmask = nft_genmask_cur(net);
644 const struct nft_hash_elem *he;
645 u32 hash, k1, k2;
646
647 k1 = *key;
648 hash = jhash_1word(a: k1, initval: priv->seed);
649 hash = reciprocal_scale(val: hash, ep_ro: priv->buckets);
650 hlist_for_each_entry_rcu(he, &priv->table[hash], node) {
651 k2 = *(u32 *)nft_set_ext_key(ext: &he->ext)->data;
652 if (k1 == k2 &&
653 nft_set_elem_active(ext: &he->ext, genmask))
654 return &he->ext;
655 }
656 return NULL;
657}
658
659static u32 nft_jhash(const struct nft_set *set, const struct nft_hash *priv,
660 const struct nft_set_ext *ext)
661{
662 const struct nft_data *key = nft_set_ext_key(ext);
663 u32 hash, k1;
664
665 if (set->klen == 4) {
666 k1 = *(u32 *)key;
667 hash = jhash_1word(a: k1, initval: priv->seed);
668 } else {
669 hash = jhash(key, length: set->klen, initval: priv->seed);
670 }
671 hash = reciprocal_scale(val: hash, ep_ro: priv->buckets);
672
673 return hash;
674}
675
676static int nft_hash_insert(const struct net *net, const struct nft_set *set,
677 const struct nft_set_elem *elem,
678 struct nft_elem_priv **elem_priv)
679{
680 struct nft_hash_elem *this = nft_elem_priv_cast(priv: elem->priv), *he;
681 struct nft_hash *priv = nft_set_priv(set);
682 u8 genmask = nft_genmask_next(net);
683 u32 hash;
684
685 hash = nft_jhash(set, priv, ext: &this->ext);
686 hlist_for_each_entry(he, &priv->table[hash], node) {
687 if (!memcmp(p: nft_set_ext_key(ext: &this->ext),
688 q: nft_set_ext_key(ext: &he->ext), size: set->klen) &&
689 nft_set_elem_active(ext: &he->ext, genmask)) {
690 *elem_priv = &he->priv;
691 return -EEXIST;
692 }
693 }
694 hlist_add_head_rcu(n: &this->node, h: &priv->table[hash]);
695 return 0;
696}
697
698static void nft_hash_activate(const struct net *net, const struct nft_set *set,
699 struct nft_elem_priv *elem_priv)
700{
701 struct nft_hash_elem *he = nft_elem_priv_cast(priv: elem_priv);
702
703 nft_clear(net, &he->ext);
704}
705
706static void nft_hash_flush(const struct net *net,
707 const struct nft_set *set,
708 struct nft_elem_priv *elem_priv)
709{
710 struct nft_hash_elem *he = nft_elem_priv_cast(priv: elem_priv);
711
712 nft_set_elem_change_active(net, set, ext: &he->ext);
713}
714
715static struct nft_elem_priv *
716nft_hash_deactivate(const struct net *net, const struct nft_set *set,
717 const struct nft_set_elem *elem)
718{
719 struct nft_hash_elem *this = nft_elem_priv_cast(priv: elem->priv), *he;
720 struct nft_hash *priv = nft_set_priv(set);
721 u8 genmask = nft_genmask_next(net);
722 u32 hash;
723
724 hash = nft_jhash(set, priv, ext: &this->ext);
725 hlist_for_each_entry(he, &priv->table[hash], node) {
726 if (!memcmp(p: nft_set_ext_key(ext: &he->ext), q: &elem->key.val,
727 size: set->klen) &&
728 nft_set_elem_active(ext: &he->ext, genmask)) {
729 nft_set_elem_change_active(net, set, ext: &he->ext);
730 return &he->priv;
731 }
732 }
733 return NULL;
734}
735
736static void nft_hash_remove(const struct net *net,
737 const struct nft_set *set,
738 struct nft_elem_priv *elem_priv)
739{
740 struct nft_hash_elem *he = nft_elem_priv_cast(priv: elem_priv);
741
742 hlist_del_rcu(n: &he->node);
743}
744
745static void nft_hash_walk(const struct nft_ctx *ctx, struct nft_set *set,
746 struct nft_set_iter *iter)
747{
748 struct nft_hash *priv = nft_set_priv(set);
749 struct nft_hash_elem *he;
750 int i;
751
752 for (i = 0; i < priv->buckets; i++) {
753 hlist_for_each_entry_rcu(he, &priv->table[i], node,
754 lockdep_is_held(&nft_pernet(ctx->net)->commit_mutex)) {
755 if (iter->count < iter->skip)
756 goto cont;
757
758 iter->err = iter->fn(ctx, set, iter, &he->priv);
759 if (iter->err < 0)
760 return;
761cont:
762 iter->count++;
763 }
764 }
765}
766
767static u64 nft_hash_privsize(const struct nlattr * const nla[],
768 const struct nft_set_desc *desc)
769{
770 return sizeof(struct nft_hash) +
771 (u64)nft_hash_buckets(size: desc->size) * sizeof(struct hlist_head);
772}
773
774static int nft_hash_init(const struct nft_set *set,
775 const struct nft_set_desc *desc,
776 const struct nlattr * const tb[])
777{
778 struct nft_hash *priv = nft_set_priv(set);
779
780 priv->buckets = nft_hash_buckets(size: desc->size);
781 get_random_bytes(buf: &priv->seed, len: sizeof(priv->seed));
782
783 return 0;
784}
785
786static void nft_hash_destroy(const struct nft_ctx *ctx,
787 const struct nft_set *set)
788{
789 struct nft_hash *priv = nft_set_priv(set);
790 struct nft_hash_elem *he;
791 struct hlist_node *next;
792 int i;
793
794 for (i = 0; i < priv->buckets; i++) {
795 hlist_for_each_entry_safe(he, next, &priv->table[i], node) {
796 hlist_del_rcu(n: &he->node);
797 nf_tables_set_elem_destroy(ctx, set, elem_priv: &he->priv);
798 }
799 }
800}
801
802static bool nft_hash_estimate(const struct nft_set_desc *desc, u32 features,
803 struct nft_set_estimate *est)
804{
805 if (!desc->size)
806 return false;
807
808 if (desc->klen == 4)
809 return false;
810
811 est->size = sizeof(struct nft_hash) +
812 (u64)nft_hash_buckets(size: desc->size) * sizeof(struct hlist_head) +
813 (u64)desc->size * sizeof(struct nft_hash_elem);
814 est->lookup = NFT_SET_CLASS_O_1;
815 est->space = NFT_SET_CLASS_O_N;
816
817 return true;
818}
819
820static bool nft_hash_fast_estimate(const struct nft_set_desc *desc, u32 features,
821 struct nft_set_estimate *est)
822{
823 if (!desc->size)
824 return false;
825
826 if (desc->klen != 4)
827 return false;
828
829 est->size = sizeof(struct nft_hash) +
830 (u64)nft_hash_buckets(size: desc->size) * sizeof(struct hlist_head) +
831 (u64)desc->size * sizeof(struct nft_hash_elem);
832 est->lookup = NFT_SET_CLASS_O_1;
833 est->space = NFT_SET_CLASS_O_N;
834
835 return true;
836}
837
838const struct nft_set_type nft_set_rhash_type = {
839 .features = NFT_SET_MAP | NFT_SET_OBJECT |
840 NFT_SET_TIMEOUT | NFT_SET_EVAL,
841 .ops = {
842 .privsize = nft_rhash_privsize,
843 .elemsize = offsetof(struct nft_rhash_elem, ext),
844 .estimate = nft_rhash_estimate,
845 .init = nft_rhash_init,
846 .gc_init = nft_rhash_gc_init,
847 .destroy = nft_rhash_destroy,
848 .insert = nft_rhash_insert,
849 .activate = nft_rhash_activate,
850 .deactivate = nft_rhash_deactivate,
851 .flush = nft_rhash_flush,
852 .remove = nft_rhash_remove,
853 .lookup = nft_rhash_lookup,
854 .update = nft_rhash_update,
855 .delete = nft_rhash_delete,
856 .walk = nft_rhash_walk,
857 .get = nft_rhash_get,
858 },
859};
860
861const struct nft_set_type nft_set_hash_type = {
862 .features = NFT_SET_MAP | NFT_SET_OBJECT,
863 .ops = {
864 .privsize = nft_hash_privsize,
865 .elemsize = offsetof(struct nft_hash_elem, ext),
866 .estimate = nft_hash_estimate,
867 .init = nft_hash_init,
868 .destroy = nft_hash_destroy,
869 .insert = nft_hash_insert,
870 .activate = nft_hash_activate,
871 .deactivate = nft_hash_deactivate,
872 .flush = nft_hash_flush,
873 .remove = nft_hash_remove,
874 .lookup = nft_hash_lookup,
875 .walk = nft_hash_walk,
876 .get = nft_hash_get,
877 },
878};
879
880const struct nft_set_type nft_set_hash_fast_type = {
881 .features = NFT_SET_MAP | NFT_SET_OBJECT,
882 .ops = {
883 .privsize = nft_hash_privsize,
884 .elemsize = offsetof(struct nft_hash_elem, ext),
885 .estimate = nft_hash_fast_estimate,
886 .init = nft_hash_init,
887 .destroy = nft_hash_destroy,
888 .insert = nft_hash_insert,
889 .activate = nft_hash_activate,
890 .deactivate = nft_hash_deactivate,
891 .flush = nft_hash_flush,
892 .remove = nft_hash_remove,
893 .lookup = nft_hash_lookup_fast,
894 .walk = nft_hash_walk,
895 .get = nft_hash_get,
896 },
897};
898

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