2 * Copyright (c) 2008-2014 Patrick McHardy <kaber@trash.net>
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
8 * Development of this code funded by Astaro AG (http://www.astaro.com/)
11 #include <linux/kernel.h>
12 #include <linux/init.h>
13 #include <linux/module.h>
14 #include <linux/list.h>
15 #include <linux/log2.h>
16 #include <linux/jhash.h>
17 #include <linux/netlink.h>
18 #include <linux/workqueue.h>
19 #include <linux/rhashtable.h>
20 #include <linux/netfilter.h>
21 #include <linux/netfilter/nf_tables.h>
22 #include <net/netfilter/nf_tables.h>
24 /* We target a hash table size of 4, element hint is 75% of final size */
25 #define NFT_RHASH_ELEMENT_HINT 3
29 struct delayed_work gc_work;
32 struct nft_rhash_elem {
33 struct rhash_head node;
34 struct nft_set_ext ext;
37 struct nft_rhash_cmp_arg {
38 const struct nft_set *set;
43 static inline u32 nft_rhash_key(const void *data, u32 len, u32 seed)
45 const struct nft_rhash_cmp_arg *arg = data;
47 return jhash(arg->key, len, seed);
50 static inline u32 nft_rhash_obj(const void *data, u32 len, u32 seed)
52 const struct nft_rhash_elem *he = data;
54 return jhash(nft_set_ext_key(&he->ext), len, seed);
57 static inline int nft_rhash_cmp(struct rhashtable_compare_arg *arg,
60 const struct nft_rhash_cmp_arg *x = arg->key;
61 const struct nft_rhash_elem *he = ptr;
63 if (memcmp(nft_set_ext_key(&he->ext), x->key, x->set->klen))
65 if (nft_set_elem_expired(&he->ext))
67 if (!nft_set_elem_active(&he->ext, x->genmask))
72 static const struct rhashtable_params nft_rhash_params = {
73 .head_offset = offsetof(struct nft_rhash_elem, node),
74 .hashfn = nft_rhash_key,
75 .obj_hashfn = nft_rhash_obj,
76 .obj_cmpfn = nft_rhash_cmp,
77 .automatic_shrinking = true,
80 static bool nft_rhash_lookup(const struct net *net, const struct nft_set *set,
81 const u32 *key, const struct nft_set_ext **ext)
83 struct nft_rhash *priv = nft_set_priv(set);
84 const struct nft_rhash_elem *he;
85 struct nft_rhash_cmp_arg arg = {
86 .genmask = nft_genmask_cur(net),
91 he = rhashtable_lookup_fast(&priv->ht, &arg, nft_rhash_params);
98 static void *nft_rhash_get(const struct net *net, const struct nft_set *set,
99 const struct nft_set_elem *elem, unsigned int flags)
101 struct nft_rhash *priv = nft_set_priv(set);
102 struct nft_rhash_elem *he;
103 struct nft_rhash_cmp_arg arg = {
104 .genmask = nft_genmask_cur(net),
106 .key = elem->key.val.data,
109 he = rhashtable_lookup_fast(&priv->ht, &arg, nft_rhash_params);
113 return ERR_PTR(-ENOENT);
116 static bool nft_rhash_update(struct nft_set *set, const u32 *key,
117 void *(*new)(struct nft_set *,
118 const struct nft_expr *,
119 struct nft_regs *regs),
120 const struct nft_expr *expr,
121 struct nft_regs *regs,
122 const struct nft_set_ext **ext)
124 struct nft_rhash *priv = nft_set_priv(set);
125 struct nft_rhash_elem *he, *prev;
126 struct nft_rhash_cmp_arg arg = {
127 .genmask = NFT_GENMASK_ANY,
132 he = rhashtable_lookup_fast(&priv->ht, &arg, nft_rhash_params);
136 he = new(set, expr, regs);
140 prev = rhashtable_lookup_get_insert_key(&priv->ht, &arg, &he->node,
145 /* Another cpu may race to insert the element with the same key */
147 nft_set_elem_destroy(set, he, true);
156 nft_set_elem_destroy(set, he, true);
161 static int nft_rhash_insert(const struct net *net, const struct nft_set *set,
162 const struct nft_set_elem *elem,
163 struct nft_set_ext **ext)
165 struct nft_rhash *priv = nft_set_priv(set);
166 struct nft_rhash_elem *he = elem->priv;
167 struct nft_rhash_cmp_arg arg = {
168 .genmask = nft_genmask_next(net),
170 .key = elem->key.val.data,
172 struct nft_rhash_elem *prev;
174 prev = rhashtable_lookup_get_insert_key(&priv->ht, &arg, &he->node,
177 return PTR_ERR(prev);
185 static void nft_rhash_activate(const struct net *net, const struct nft_set *set,
186 const struct nft_set_elem *elem)
188 struct nft_rhash_elem *he = elem->priv;
190 nft_set_elem_change_active(net, set, &he->ext);
191 nft_set_elem_clear_busy(&he->ext);
194 static bool nft_rhash_flush(const struct net *net,
195 const struct nft_set *set, void *priv)
197 struct nft_rhash_elem *he = priv;
199 if (!nft_set_elem_mark_busy(&he->ext) ||
200 !nft_is_active(net, &he->ext)) {
201 nft_set_elem_change_active(net, set, &he->ext);
207 static void *nft_rhash_deactivate(const struct net *net,
208 const struct nft_set *set,
209 const struct nft_set_elem *elem)
211 struct nft_rhash *priv = nft_set_priv(set);
212 struct nft_rhash_elem *he;
213 struct nft_rhash_cmp_arg arg = {
214 .genmask = nft_genmask_next(net),
216 .key = elem->key.val.data,
220 he = rhashtable_lookup_fast(&priv->ht, &arg, nft_rhash_params);
222 !nft_rhash_flush(net, set, he))
230 static void nft_rhash_remove(const struct net *net,
231 const struct nft_set *set,
232 const struct nft_set_elem *elem)
234 struct nft_rhash *priv = nft_set_priv(set);
235 struct nft_rhash_elem *he = elem->priv;
237 rhashtable_remove_fast(&priv->ht, &he->node, nft_rhash_params);
240 static void nft_rhash_walk(const struct nft_ctx *ctx, struct nft_set *set,
241 struct nft_set_iter *iter)
243 struct nft_rhash *priv = nft_set_priv(set);
244 struct nft_rhash_elem *he;
245 struct rhashtable_iter hti;
246 struct nft_set_elem elem;
249 err = rhashtable_walk_init(&priv->ht, &hti, GFP_ATOMIC);
254 err = rhashtable_walk_start(&hti);
255 if (err && err != -EAGAIN) {
260 while ((he = rhashtable_walk_next(&hti))) {
263 if (err != -EAGAIN) {
271 if (iter->count < iter->skip)
273 if (nft_set_elem_expired(&he->ext))
275 if (!nft_set_elem_active(&he->ext, iter->genmask))
280 iter->err = iter->fn(ctx, set, iter, &elem);
289 rhashtable_walk_stop(&hti);
290 rhashtable_walk_exit(&hti);
293 static void nft_rhash_gc(struct work_struct *work)
296 struct nft_rhash_elem *he;
297 struct nft_rhash *priv;
298 struct nft_set_gc_batch *gcb = NULL;
299 struct rhashtable_iter hti;
302 priv = container_of(work, struct nft_rhash, gc_work.work);
303 set = nft_set_container_of(priv);
305 err = rhashtable_walk_init(&priv->ht, &hti, GFP_KERNEL);
309 err = rhashtable_walk_start(&hti);
310 if (err && err != -EAGAIN)
313 while ((he = rhashtable_walk_next(&hti))) {
315 if (PTR_ERR(he) != -EAGAIN)
320 if (!nft_set_elem_expired(&he->ext))
322 if (nft_set_elem_mark_busy(&he->ext))
325 gcb = nft_set_gc_batch_check(set, gcb, GFP_ATOMIC);
328 rhashtable_remove_fast(&priv->ht, &he->node, nft_rhash_params);
329 atomic_dec(&set->nelems);
330 nft_set_gc_batch_add(gcb, he);
333 rhashtable_walk_stop(&hti);
334 rhashtable_walk_exit(&hti);
336 nft_set_gc_batch_complete(gcb);
338 queue_delayed_work(system_power_efficient_wq, &priv->gc_work,
339 nft_set_gc_interval(set));
342 static unsigned int nft_rhash_privsize(const struct nlattr * const nla[],
343 const struct nft_set_desc *desc)
345 return sizeof(struct nft_rhash);
348 static int nft_rhash_init(const struct nft_set *set,
349 const struct nft_set_desc *desc,
350 const struct nlattr * const tb[])
352 struct nft_rhash *priv = nft_set_priv(set);
353 struct rhashtable_params params = nft_rhash_params;
356 params.nelem_hint = desc->size ?: NFT_RHASH_ELEMENT_HINT;
357 params.key_len = set->klen;
359 err = rhashtable_init(&priv->ht, ¶ms);
363 INIT_DEFERRABLE_WORK(&priv->gc_work, nft_rhash_gc);
364 if (set->flags & NFT_SET_TIMEOUT)
365 queue_delayed_work(system_power_efficient_wq, &priv->gc_work,
366 nft_set_gc_interval(set));
370 static void nft_rhash_elem_destroy(void *ptr, void *arg)
372 nft_set_elem_destroy(arg, ptr, true);
375 static void nft_rhash_destroy(const struct nft_set *set)
377 struct nft_rhash *priv = nft_set_priv(set);
379 cancel_delayed_work_sync(&priv->gc_work);
380 rhashtable_free_and_destroy(&priv->ht, nft_rhash_elem_destroy,
384 static u32 nft_hash_buckets(u32 size)
386 return roundup_pow_of_two(size * 4 / 3);
389 static bool nft_rhash_estimate(const struct nft_set_desc *desc, u32 features,
390 struct nft_set_estimate *est)
393 est->lookup = NFT_SET_CLASS_O_1;
394 est->space = NFT_SET_CLASS_O_N;
402 struct hlist_head table[];
405 struct nft_hash_elem {
406 struct hlist_node node;
407 struct nft_set_ext ext;
410 static bool nft_hash_lookup(const struct net *net, const struct nft_set *set,
411 const u32 *key, const struct nft_set_ext **ext)
413 struct nft_hash *priv = nft_set_priv(set);
414 u8 genmask = nft_genmask_cur(net);
415 const struct nft_hash_elem *he;
418 hash = jhash(key, set->klen, priv->seed);
419 hash = reciprocal_scale(hash, priv->buckets);
420 hlist_for_each_entry_rcu(he, &priv->table[hash], node) {
421 if (!memcmp(nft_set_ext_key(&he->ext), key, set->klen) &&
422 nft_set_elem_active(&he->ext, genmask)) {
430 static void *nft_hash_get(const struct net *net, const struct nft_set *set,
431 const struct nft_set_elem *elem, unsigned int flags)
433 struct nft_hash *priv = nft_set_priv(set);
434 u8 genmask = nft_genmask_cur(net);
435 struct nft_hash_elem *he;
438 hash = jhash(elem->key.val.data, set->klen, priv->seed);
439 hash = reciprocal_scale(hash, priv->buckets);
440 hlist_for_each_entry_rcu(he, &priv->table[hash], node) {
441 if (!memcmp(nft_set_ext_key(&he->ext), elem->key.val.data, set->klen) &&
442 nft_set_elem_active(&he->ext, genmask))
445 return ERR_PTR(-ENOENT);
448 /* nft_hash_select_ops() makes sure key size can be either 2 or 4 bytes . */
449 static inline u32 nft_hash_key(const u32 *key, u32 klen)
457 static bool nft_hash_lookup_fast(const struct net *net,
458 const struct nft_set *set,
459 const u32 *key, const struct nft_set_ext **ext)
461 struct nft_hash *priv = nft_set_priv(set);
462 u8 genmask = nft_genmask_cur(net);
463 const struct nft_hash_elem *he;
466 k1 = nft_hash_key(key, set->klen);
467 hash = jhash_1word(k1, priv->seed);
468 hash = reciprocal_scale(hash, priv->buckets);
469 hlist_for_each_entry_rcu(he, &priv->table[hash], node) {
470 k2 = nft_hash_key(nft_set_ext_key(&he->ext)->data, set->klen);
472 nft_set_elem_active(&he->ext, genmask)) {
480 static int nft_hash_insert(const struct net *net, const struct nft_set *set,
481 const struct nft_set_elem *elem,
482 struct nft_set_ext **ext)
484 struct nft_hash_elem *this = elem->priv, *he;
485 struct nft_hash *priv = nft_set_priv(set);
486 u8 genmask = nft_genmask_next(net);
489 hash = jhash(nft_set_ext_key(&this->ext), set->klen, priv->seed);
490 hash = reciprocal_scale(hash, priv->buckets);
491 hlist_for_each_entry(he, &priv->table[hash], node) {
492 if (!memcmp(nft_set_ext_key(&this->ext),
493 nft_set_ext_key(&he->ext), set->klen) &&
494 nft_set_elem_active(&he->ext, genmask)) {
499 hlist_add_head_rcu(&this->node, &priv->table[hash]);
503 static void nft_hash_activate(const struct net *net, const struct nft_set *set,
504 const struct nft_set_elem *elem)
506 struct nft_hash_elem *he = elem->priv;
508 nft_set_elem_change_active(net, set, &he->ext);
511 static bool nft_hash_flush(const struct net *net,
512 const struct nft_set *set, void *priv)
514 struct nft_hash_elem *he = priv;
516 nft_set_elem_change_active(net, set, &he->ext);
520 static void *nft_hash_deactivate(const struct net *net,
521 const struct nft_set *set,
522 const struct nft_set_elem *elem)
524 struct nft_hash *priv = nft_set_priv(set);
525 struct nft_hash_elem *this = elem->priv, *he;
526 u8 genmask = nft_genmask_next(net);
529 hash = jhash(nft_set_ext_key(&this->ext), set->klen, priv->seed);
530 hash = reciprocal_scale(hash, priv->buckets);
531 hlist_for_each_entry(he, &priv->table[hash], node) {
532 if (!memcmp(nft_set_ext_key(&this->ext), &elem->key.val,
534 nft_set_elem_active(&he->ext, genmask)) {
535 nft_set_elem_change_active(net, set, &he->ext);
542 static void nft_hash_remove(const struct net *net,
543 const struct nft_set *set,
544 const struct nft_set_elem *elem)
546 struct nft_hash_elem *he = elem->priv;
548 hlist_del_rcu(&he->node);
551 static void nft_hash_walk(const struct nft_ctx *ctx, struct nft_set *set,
552 struct nft_set_iter *iter)
554 struct nft_hash *priv = nft_set_priv(set);
555 struct nft_hash_elem *he;
556 struct nft_set_elem elem;
559 for (i = 0; i < priv->buckets; i++) {
560 hlist_for_each_entry_rcu(he, &priv->table[i], node) {
561 if (iter->count < iter->skip)
563 if (!nft_set_elem_active(&he->ext, iter->genmask))
568 iter->err = iter->fn(ctx, set, iter, &elem);
577 static unsigned int nft_hash_privsize(const struct nlattr * const nla[],
578 const struct nft_set_desc *desc)
580 return sizeof(struct nft_hash) +
581 nft_hash_buckets(desc->size) * sizeof(struct hlist_head);
584 static int nft_hash_init(const struct nft_set *set,
585 const struct nft_set_desc *desc,
586 const struct nlattr * const tb[])
588 struct nft_hash *priv = nft_set_priv(set);
590 priv->buckets = nft_hash_buckets(desc->size);
591 get_random_bytes(&priv->seed, sizeof(priv->seed));
596 static void nft_hash_destroy(const struct nft_set *set)
598 struct nft_hash *priv = nft_set_priv(set);
599 struct nft_hash_elem *he;
600 struct hlist_node *next;
603 for (i = 0; i < priv->buckets; i++) {
604 hlist_for_each_entry_safe(he, next, &priv->table[i], node) {
605 hlist_del_rcu(&he->node);
606 nft_set_elem_destroy(set, he, true);
611 static bool nft_hash_estimate(const struct nft_set_desc *desc, u32 features,
612 struct nft_set_estimate *est)
614 est->size = sizeof(struct nft_hash) +
615 nft_hash_buckets(desc->size) * sizeof(struct hlist_head) +
616 desc->size * sizeof(struct nft_hash_elem);
617 est->lookup = NFT_SET_CLASS_O_1;
618 est->space = NFT_SET_CLASS_O_N;
623 static struct nft_set_type nft_hash_type;
624 static struct nft_set_ops nft_rhash_ops __read_mostly = {
625 .type = &nft_hash_type,
626 .privsize = nft_rhash_privsize,
627 .elemsize = offsetof(struct nft_rhash_elem, ext),
628 .estimate = nft_rhash_estimate,
629 .init = nft_rhash_init,
630 .destroy = nft_rhash_destroy,
631 .insert = nft_rhash_insert,
632 .activate = nft_rhash_activate,
633 .deactivate = nft_rhash_deactivate,
634 .flush = nft_rhash_flush,
635 .remove = nft_rhash_remove,
636 .lookup = nft_rhash_lookup,
637 .update = nft_rhash_update,
638 .walk = nft_rhash_walk,
639 .get = nft_rhash_get,
640 .features = NFT_SET_MAP | NFT_SET_OBJECT | NFT_SET_TIMEOUT,
643 static struct nft_set_ops nft_hash_ops __read_mostly = {
644 .type = &nft_hash_type,
645 .privsize = nft_hash_privsize,
646 .elemsize = offsetof(struct nft_hash_elem, ext),
647 .estimate = nft_hash_estimate,
648 .init = nft_hash_init,
649 .destroy = nft_hash_destroy,
650 .insert = nft_hash_insert,
651 .activate = nft_hash_activate,
652 .deactivate = nft_hash_deactivate,
653 .flush = nft_hash_flush,
654 .remove = nft_hash_remove,
655 .lookup = nft_hash_lookup,
656 .walk = nft_hash_walk,
658 .features = NFT_SET_MAP | NFT_SET_OBJECT,
661 static struct nft_set_ops nft_hash_fast_ops __read_mostly = {
662 .type = &nft_hash_type,
663 .privsize = nft_hash_privsize,
664 .elemsize = offsetof(struct nft_hash_elem, ext),
665 .estimate = nft_hash_estimate,
666 .init = nft_hash_init,
667 .destroy = nft_hash_destroy,
668 .insert = nft_hash_insert,
669 .activate = nft_hash_activate,
670 .deactivate = nft_hash_deactivate,
671 .flush = nft_hash_flush,
672 .remove = nft_hash_remove,
673 .lookup = nft_hash_lookup_fast,
674 .walk = nft_hash_walk,
676 .features = NFT_SET_MAP | NFT_SET_OBJECT,
679 static const struct nft_set_ops *
680 nft_hash_select_ops(const struct nft_ctx *ctx, const struct nft_set_desc *desc,
684 switch (desc->klen) {
686 return &nft_hash_fast_ops;
688 return &nft_hash_ops;
692 return &nft_rhash_ops;
695 static struct nft_set_type nft_hash_type __read_mostly = {
696 .select_ops = nft_hash_select_ops,
697 .owner = THIS_MODULE,
700 static int __init nft_hash_module_init(void)
702 return nft_register_set(&nft_hash_type);
705 static void __exit nft_hash_module_exit(void)
707 nft_unregister_set(&nft_hash_type);
710 module_init(nft_hash_module_init);
711 module_exit(nft_hash_module_exit);
713 MODULE_LICENSE("GPL");
714 MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
715 MODULE_ALIAS_NFT_SET();