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1/*
2 * Generic address resolution entity
3 *
4 * Authors:
5 * Pedro Roque <roque@di.fc.ul.pt>
6 * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License
10 * as published by the Free Software Foundation; either version
11 * 2 of the License, or (at your option) any later version.
12 *
13 * Fixes:
14 * Vitaly E. Lavrov releasing NULL neighbor in neigh_add.
15 * Harald Welte Add neighbour cache statistics like rtstat
16 */
17
18#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
19
20#include <linux/slab.h>
21#include <linux/types.h>
22#include <linux/kernel.h>
23#include <linux/module.h>
24#include <linux/socket.h>
25#include <linux/netdevice.h>
26#include <linux/proc_fs.h>
27#ifdef CONFIG_SYSCTL
28#include <linux/sysctl.h>
29#endif
30#include <linux/times.h>
31#include <net/net_namespace.h>
32#include <net/neighbour.h>
33#include <net/dst.h>
34#include <net/sock.h>
35#include <net/netevent.h>
36#include <net/netlink.h>
37#include <linux/rtnetlink.h>
38#include <linux/random.h>
39#include <linux/string.h>
40#include <linux/log2.h>
41#include <linux/inetdevice.h>
42#include <net/addrconf.h>
43
44#define DEBUG
45#define NEIGH_DEBUG 1
46#define neigh_dbg(level, fmt, ...) \
47do { \
48 if (level <= NEIGH_DEBUG) \
49 pr_debug(fmt, ##__VA_ARGS__); \
50} while (0)
51
52#define PNEIGH_HASHMASK 0xF
53
54static void neigh_timer_handler(unsigned long arg);
55static void __neigh_notify(struct neighbour *n, int type, int flags);
56static void neigh_update_notify(struct neighbour *neigh);
57static int pneigh_ifdown(struct neigh_table *tbl, struct net_device *dev);
58
59#ifdef CONFIG_PROC_FS
60static const struct file_operations neigh_stat_seq_fops;
61#endif
62
63/*
64 Neighbour hash table buckets are protected with rwlock tbl->lock.
65
66 - All the scans/updates to hash buckets MUST be made under this lock.
67 - NOTHING clever should be made under this lock: no callbacks
68 to protocol backends, no attempts to send something to network.
69 It will result in deadlocks, if backend/driver wants to use neighbour
70 cache.
71 - If the entry requires some non-trivial actions, increase
72 its reference count and release table lock.
73
74 Neighbour entries are protected:
75 - with reference count.
76 - with rwlock neigh->lock
77
78 Reference count prevents destruction.
79
80 neigh->lock mainly serializes ll address data and its validity state.
81 However, the same lock is used to protect another entry fields:
82 - timer
83 - resolution queue
84
85 Again, nothing clever shall be made under neigh->lock,
86 the most complicated procedure, which we allow is dev->hard_header.
87 It is supposed, that dev->hard_header is simplistic and does
88 not make callbacks to neighbour tables.
89 */
90
91static int neigh_blackhole(struct neighbour *neigh, struct sk_buff *skb)
92{
93 kfree_skb(skb);
94 return -ENETDOWN;
95}
96
97static void neigh_cleanup_and_release(struct neighbour *neigh)
98{
99 if (neigh->parms->neigh_cleanup)
100 neigh->parms->neigh_cleanup(neigh);
101
102 __neigh_notify(neigh, RTM_DELNEIGH, 0);
103 neigh_release(neigh);
104}
105
106/*
107 * It is random distribution in the interval (1/2)*base...(3/2)*base.
108 * It corresponds to default IPv6 settings and is not overridable,
109 * because it is really reasonable choice.
110 */
111
112unsigned long neigh_rand_reach_time(unsigned long base)
113{
114 return base ? (prandom_u32() % base) + (base >> 1) : 0;
115}
116EXPORT_SYMBOL(neigh_rand_reach_time);
117
118
119static int neigh_forced_gc(struct neigh_table *tbl)
120{
121 int shrunk = 0;
122 int i;
123 struct neigh_hash_table *nht;
124
125 NEIGH_CACHE_STAT_INC(tbl, forced_gc_runs);
126
127 write_lock_bh(&tbl->lock);
128 nht = rcu_dereference_protected(tbl->nht,
129 lockdep_is_held(&tbl->lock));
130 for (i = 0; i < (1 << nht->hash_shift); i++) {
131 struct neighbour *n;
132 struct neighbour __rcu **np;
133
134 np = &nht->hash_buckets[i];
135 while ((n = rcu_dereference_protected(*np,
136 lockdep_is_held(&tbl->lock))) != NULL) {
137 /* Neighbour record may be discarded if:
138 * - nobody refers to it.
139 * - it is not permanent
140 */
141 write_lock(&n->lock);
142 if (atomic_read(&n->refcnt) == 1 &&
143 !(n->nud_state & NUD_PERMANENT)) {
144 rcu_assign_pointer(*np,
145 rcu_dereference_protected(n->next,
146 lockdep_is_held(&tbl->lock)));
147 n->dead = 1;
148 shrunk = 1;
149 write_unlock(&n->lock);
150 neigh_cleanup_and_release(n);
151 continue;
152 }
153 write_unlock(&n->lock);
154 np = &n->next;
155 }
156 }
157
158 tbl->last_flush = jiffies;
159
160 write_unlock_bh(&tbl->lock);
161
162 return shrunk;
163}
164
165static void neigh_add_timer(struct neighbour *n, unsigned long when)
166{
167 neigh_hold(n);
168 if (unlikely(mod_timer(&n->timer, when))) {
169 printk("NEIGH: BUG, double timer add, state is %x\n",
170 n->nud_state);
171 dump_stack();
172 }
173}
174
175static int neigh_del_timer(struct neighbour *n)
176{
177 if ((n->nud_state & NUD_IN_TIMER) &&
178 del_timer(&n->timer)) {
179 neigh_release(n);
180 return 1;
181 }
182 return 0;
183}
184
185static void pneigh_queue_purge(struct sk_buff_head *list)
186{
187 struct sk_buff *skb;
188
189 while ((skb = skb_dequeue(list)) != NULL) {
190 dev_put(skb->dev);
191 kfree_skb(skb);
192 }
193}
194
195static void neigh_flush_dev(struct neigh_table *tbl, struct net_device *dev)
196{
197 int i;
198 struct neigh_hash_table *nht;
199
200 nht = rcu_dereference_protected(tbl->nht,
201 lockdep_is_held(&tbl->lock));
202
203 for (i = 0; i < (1 << nht->hash_shift); i++) {
204 struct neighbour *n;
205 struct neighbour __rcu **np = &nht->hash_buckets[i];
206
207 while ((n = rcu_dereference_protected(*np,
208 lockdep_is_held(&tbl->lock))) != NULL) {
209 if (dev && n->dev != dev) {
210 np = &n->next;
211 continue;
212 }
213 rcu_assign_pointer(*np,
214 rcu_dereference_protected(n->next,
215 lockdep_is_held(&tbl->lock)));
216 write_lock(&n->lock);
217 neigh_del_timer(n);
218 n->dead = 1;
219
220 if (atomic_read(&n->refcnt) != 1) {
221 /* The most unpleasant situation.
222 We must destroy neighbour entry,
223 but someone still uses it.
224
225 The destroy will be delayed until
226 the last user releases us, but
227 we must kill timers etc. and move
228 it to safe state.
229 */
230 __skb_queue_purge(&n->arp_queue);
231 n->arp_queue_len_bytes = 0;
232 n->output = neigh_blackhole;
233 if (n->nud_state & NUD_VALID)
234 n->nud_state = NUD_NOARP;
235 else
236 n->nud_state = NUD_NONE;
237 neigh_dbg(2, "neigh %p is stray\n", n);
238 }
239 write_unlock(&n->lock);
240 neigh_cleanup_and_release(n);
241 }
242 }
243}
244
245void neigh_changeaddr(struct neigh_table *tbl, struct net_device *dev)
246{
247 write_lock_bh(&tbl->lock);
248 neigh_flush_dev(tbl, dev);
249 write_unlock_bh(&tbl->lock);
250}
251EXPORT_SYMBOL(neigh_changeaddr);
252
253int neigh_ifdown(struct neigh_table *tbl, struct net_device *dev)
254{
255 write_lock_bh(&tbl->lock);
256 neigh_flush_dev(tbl, dev);
257 pneigh_ifdown(tbl, dev);
258 write_unlock_bh(&tbl->lock);
259
260 del_timer_sync(&tbl->proxy_timer);
261 pneigh_queue_purge(&tbl->proxy_queue);
262 return 0;
263}
264EXPORT_SYMBOL(neigh_ifdown);
265
266static struct neighbour *neigh_alloc(struct neigh_table *tbl, struct net_device *dev)
267{
268 struct neighbour *n = NULL;
269 unsigned long now = jiffies;
270 int entries;
271
272 entries = atomic_inc_return(&tbl->entries) - 1;
273 if (entries >= tbl->gc_thresh3 ||
274 (entries >= tbl->gc_thresh2 &&
275 time_after(now, tbl->last_flush + 5 * HZ))) {
276 if (!neigh_forced_gc(tbl) &&
277 entries >= tbl->gc_thresh3) {
278 net_info_ratelimited("%s: neighbor table overflow!\n",
279 tbl->id);
280 NEIGH_CACHE_STAT_INC(tbl, table_fulls);
281 goto out_entries;
282 }
283 }
284
285 n = kzalloc(tbl->entry_size + dev->neigh_priv_len, GFP_ATOMIC);
286 if (!n)
287 goto out_entries;
288
289 __skb_queue_head_init(&n->arp_queue);
290 rwlock_init(&n->lock);
291 seqlock_init(&n->ha_lock);
292 n->updated = n->used = now;
293 n->nud_state = NUD_NONE;
294 n->output = neigh_blackhole;
295 seqlock_init(&n->hh.hh_lock);
296 n->parms = neigh_parms_clone(&tbl->parms);
297 setup_timer(&n->timer, neigh_timer_handler, (unsigned long)n);
298
299 NEIGH_CACHE_STAT_INC(tbl, allocs);
300 n->tbl = tbl;
301 atomic_set(&n->refcnt, 1);
302 n->dead = 1;
303out:
304 return n;
305
306out_entries:
307 atomic_dec(&tbl->entries);
308 goto out;
309}
310
311static void neigh_get_hash_rnd(u32 *x)
312{
313 get_random_bytes(x, sizeof(*x));
314 *x |= 1;
315}
316
317static struct neigh_hash_table *neigh_hash_alloc(unsigned int shift)
318{
319 size_t size = (1 << shift) * sizeof(struct neighbour *);
320 struct neigh_hash_table *ret;
321 struct neighbour __rcu **buckets;
322 int i;
323
324 ret = kmalloc(sizeof(*ret), GFP_ATOMIC);
325 if (!ret)
326 return NULL;
327 if (size <= PAGE_SIZE)
328 buckets = kzalloc(size, GFP_ATOMIC);
329 else
330 buckets = (struct neighbour __rcu **)
331 __get_free_pages(GFP_ATOMIC | __GFP_ZERO,
332 get_order(size));
333 if (!buckets) {
334 kfree(ret);
335 return NULL;
336 }
337 ret->hash_buckets = buckets;
338 ret->hash_shift = shift;
339 for (i = 0; i < NEIGH_NUM_HASH_RND; i++)
340 neigh_get_hash_rnd(&ret->hash_rnd[i]);
341 return ret;
342}
343
344static void neigh_hash_free_rcu(struct rcu_head *head)
345{
346 struct neigh_hash_table *nht = container_of(head,
347 struct neigh_hash_table,
348 rcu);
349 size_t size = (1 << nht->hash_shift) * sizeof(struct neighbour *);
350 struct neighbour __rcu **buckets = nht->hash_buckets;
351
352 if (size <= PAGE_SIZE)
353 kfree(buckets);
354 else
355 free_pages((unsigned long)buckets, get_order(size));
356 kfree(nht);
357}
358
359static struct neigh_hash_table *neigh_hash_grow(struct neigh_table *tbl,
360 unsigned long new_shift)
361{
362 unsigned int i, hash;
363 struct neigh_hash_table *new_nht, *old_nht;
364
365 NEIGH_CACHE_STAT_INC(tbl, hash_grows);
366
367 old_nht = rcu_dereference_protected(tbl->nht,
368 lockdep_is_held(&tbl->lock));
369 new_nht = neigh_hash_alloc(new_shift);
370 if (!new_nht)
371 return old_nht;
372
373 for (i = 0; i < (1 << old_nht->hash_shift); i++) {
374 struct neighbour *n, *next;
375
376 for (n = rcu_dereference_protected(old_nht->hash_buckets[i],
377 lockdep_is_held(&tbl->lock));
378 n != NULL;
379 n = next) {
380 hash = tbl->hash(n->primary_key, n->dev,
381 new_nht->hash_rnd);
382
383 hash >>= (32 - new_nht->hash_shift);
384 next = rcu_dereference_protected(n->next,
385 lockdep_is_held(&tbl->lock));
386
387 rcu_assign_pointer(n->next,
388 rcu_dereference_protected(
389 new_nht->hash_buckets[hash],
390 lockdep_is_held(&tbl->lock)));
391 rcu_assign_pointer(new_nht->hash_buckets[hash], n);
392 }
393 }
394
395 rcu_assign_pointer(tbl->nht, new_nht);
396 call_rcu(&old_nht->rcu, neigh_hash_free_rcu);
397 return new_nht;
398}
399
400struct neighbour *neigh_lookup(struct neigh_table *tbl, const void *pkey,
401 struct net_device *dev)
402{
403 struct neighbour *n;
404
405 NEIGH_CACHE_STAT_INC(tbl, lookups);
406
407 rcu_read_lock_bh();
408 n = __neigh_lookup_noref(tbl, pkey, dev);
409 if (n) {
410 if (!atomic_inc_not_zero(&n->refcnt))
411 n = NULL;
412 NEIGH_CACHE_STAT_INC(tbl, hits);
413 }
414
415 rcu_read_unlock_bh();
416 return n;
417}
418EXPORT_SYMBOL(neigh_lookup);
419
420struct neighbour *neigh_lookup_nodev(struct neigh_table *tbl, struct net *net,
421 const void *pkey)
422{
423 struct neighbour *n;
424 int key_len = tbl->key_len;
425 u32 hash_val;
426 struct neigh_hash_table *nht;
427
428 NEIGH_CACHE_STAT_INC(tbl, lookups);
429
430 rcu_read_lock_bh();
431 nht = rcu_dereference_bh(tbl->nht);
432 hash_val = tbl->hash(pkey, NULL, nht->hash_rnd) >> (32 - nht->hash_shift);
433
434 for (n = rcu_dereference_bh(nht->hash_buckets[hash_val]);
435 n != NULL;
436 n = rcu_dereference_bh(n->next)) {
437 if (!memcmp(n->primary_key, pkey, key_len) &&
438 net_eq(dev_net(n->dev), net)) {
439 if (!atomic_inc_not_zero(&n->refcnt))
440 n = NULL;
441 NEIGH_CACHE_STAT_INC(tbl, hits);
442 break;
443 }
444 }
445
446 rcu_read_unlock_bh();
447 return n;
448}
449EXPORT_SYMBOL(neigh_lookup_nodev);
450
451struct neighbour *__neigh_create(struct neigh_table *tbl, const void *pkey,
452 struct net_device *dev, bool want_ref)
453{
454 u32 hash_val;
455 int key_len = tbl->key_len;
456 int error;
457 struct neighbour *n1, *rc, *n = neigh_alloc(tbl, dev);
458 struct neigh_hash_table *nht;
459
460 if (!n) {
461 rc = ERR_PTR(-ENOBUFS);
462 goto out;
463 }
464
465 memcpy(n->primary_key, pkey, key_len);
466 n->dev = dev;
467 dev_hold(dev);
468
469 /* Protocol specific setup. */
470 if (tbl->constructor && (error = tbl->constructor(n)) < 0) {
471 rc = ERR_PTR(error);
472 goto out_neigh_release;
473 }
474
475 if (dev->netdev_ops->ndo_neigh_construct) {
476 error = dev->netdev_ops->ndo_neigh_construct(n);
477 if (error < 0) {
478 rc = ERR_PTR(error);
479 goto out_neigh_release;
480 }
481 }
482
483 /* Device specific setup. */
484 if (n->parms->neigh_setup &&
485 (error = n->parms->neigh_setup(n)) < 0) {
486 rc = ERR_PTR(error);
487 goto out_neigh_release;
488 }
489
490 n->confirmed = jiffies - (NEIGH_VAR(n->parms, BASE_REACHABLE_TIME) << 1);
491
492 write_lock_bh(&tbl->lock);
493 nht = rcu_dereference_protected(tbl->nht,
494 lockdep_is_held(&tbl->lock));
495
496 if (atomic_read(&tbl->entries) > (1 << nht->hash_shift))
497 nht = neigh_hash_grow(tbl, nht->hash_shift + 1);
498
499 hash_val = tbl->hash(pkey, dev, nht->hash_rnd) >> (32 - nht->hash_shift);
500
501 if (n->parms->dead) {
502 rc = ERR_PTR(-EINVAL);
503 goto out_tbl_unlock;
504 }
505
506 for (n1 = rcu_dereference_protected(nht->hash_buckets[hash_val],
507 lockdep_is_held(&tbl->lock));
508 n1 != NULL;
509 n1 = rcu_dereference_protected(n1->next,
510 lockdep_is_held(&tbl->lock))) {
511 if (dev == n1->dev && !memcmp(n1->primary_key, pkey, key_len)) {
512 if (want_ref)
513 neigh_hold(n1);
514 rc = n1;
515 goto out_tbl_unlock;
516 }
517 }
518
519 n->dead = 0;
520 if (want_ref)
521 neigh_hold(n);
522 rcu_assign_pointer(n->next,
523 rcu_dereference_protected(nht->hash_buckets[hash_val],
524 lockdep_is_held(&tbl->lock)));
525 rcu_assign_pointer(nht->hash_buckets[hash_val], n);
526 write_unlock_bh(&tbl->lock);
527 neigh_dbg(2, "neigh %p is created\n", n);
528 rc = n;
529out:
530 return rc;
531out_tbl_unlock:
532 write_unlock_bh(&tbl->lock);
533out_neigh_release:
534 neigh_release(n);
535 goto out;
536}
537EXPORT_SYMBOL(__neigh_create);
538
539static u32 pneigh_hash(const void *pkey, int key_len)
540{
541 u32 hash_val = *(u32 *)(pkey + key_len - 4);
542 hash_val ^= (hash_val >> 16);
543 hash_val ^= hash_val >> 8;
544 hash_val ^= hash_val >> 4;
545 hash_val &= PNEIGH_HASHMASK;
546 return hash_val;
547}
548
549static struct pneigh_entry *__pneigh_lookup_1(struct pneigh_entry *n,
550 struct net *net,
551 const void *pkey,
552 int key_len,
553 struct net_device *dev)
554{
555 while (n) {
556 if (!memcmp(n->key, pkey, key_len) &&
557 net_eq(pneigh_net(n), net) &&
558 (n->dev == dev || !n->dev))
559 return n;
560 n = n->next;
561 }
562 return NULL;
563}
564
565struct pneigh_entry *__pneigh_lookup(struct neigh_table *tbl,
566 struct net *net, const void *pkey, struct net_device *dev)
567{
568 int key_len = tbl->key_len;
569 u32 hash_val = pneigh_hash(pkey, key_len);
570
571 return __pneigh_lookup_1(tbl->phash_buckets[hash_val],
572 net, pkey, key_len, dev);
573}
574EXPORT_SYMBOL_GPL(__pneigh_lookup);
575
576struct pneigh_entry * pneigh_lookup(struct neigh_table *tbl,
577 struct net *net, const void *pkey,
578 struct net_device *dev, int creat)
579{
580 struct pneigh_entry *n;
581 int key_len = tbl->key_len;
582 u32 hash_val = pneigh_hash(pkey, key_len);
583
584 read_lock_bh(&tbl->lock);
585 n = __pneigh_lookup_1(tbl->phash_buckets[hash_val],
586 net, pkey, key_len, dev);
587 read_unlock_bh(&tbl->lock);
588
589 if (n || !creat)
590 goto out;
591
592 ASSERT_RTNL();
593
594 n = kmalloc(sizeof(*n) + key_len, GFP_KERNEL);
595 if (!n)
596 goto out;
597
598 write_pnet(&n->net, net);
599 memcpy(n->key, pkey, key_len);
600 n->dev = dev;
601 if (dev)
602 dev_hold(dev);
603
604 if (tbl->pconstructor && tbl->pconstructor(n)) {
605 if (dev)
606 dev_put(dev);
607 kfree(n);
608 n = NULL;
609 goto out;
610 }
611
612 write_lock_bh(&tbl->lock);
613 n->next = tbl->phash_buckets[hash_val];
614 tbl->phash_buckets[hash_val] = n;
615 write_unlock_bh(&tbl->lock);
616out:
617 return n;
618}
619EXPORT_SYMBOL(pneigh_lookup);
620
621
622int pneigh_delete(struct neigh_table *tbl, struct net *net, const void *pkey,
623 struct net_device *dev)
624{
625 struct pneigh_entry *n, **np;
626 int key_len = tbl->key_len;
627 u32 hash_val = pneigh_hash(pkey, key_len);
628
629 write_lock_bh(&tbl->lock);
630 for (np = &tbl->phash_buckets[hash_val]; (n = *np) != NULL;
631 np = &n->next) {
632 if (!memcmp(n->key, pkey, key_len) && n->dev == dev &&
633 net_eq(pneigh_net(n), net)) {
634 *np = n->next;
635 write_unlock_bh(&tbl->lock);
636 if (tbl->pdestructor)
637 tbl->pdestructor(n);
638 if (n->dev)
639 dev_put(n->dev);
640 kfree(n);
641 return 0;
642 }
643 }
644 write_unlock_bh(&tbl->lock);
645 return -ENOENT;
646}
647
648static int pneigh_ifdown(struct neigh_table *tbl, struct net_device *dev)
649{
650 struct pneigh_entry *n, **np;
651 u32 h;
652
653 for (h = 0; h <= PNEIGH_HASHMASK; h++) {
654 np = &tbl->phash_buckets[h];
655 while ((n = *np) != NULL) {
656 if (!dev || n->dev == dev) {
657 *np = n->next;
658 if (tbl->pdestructor)
659 tbl->pdestructor(n);
660 if (n->dev)
661 dev_put(n->dev);
662 kfree(n);
663 continue;
664 }
665 np = &n->next;
666 }
667 }
668 return -ENOENT;
669}
670
671static void neigh_parms_destroy(struct neigh_parms *parms);
672
673static inline void neigh_parms_put(struct neigh_parms *parms)
674{
675 if (atomic_dec_and_test(&parms->refcnt))
676 neigh_parms_destroy(parms);
677}
678
679/*
680 * neighbour must already be out of the table;
681 *
682 */
683void neigh_destroy(struct neighbour *neigh)
684{
685 struct net_device *dev = neigh->dev;
686
687 NEIGH_CACHE_STAT_INC(neigh->tbl, destroys);
688
689 if (!neigh->dead) {
690 pr_warn("Destroying alive neighbour %p\n", neigh);
691 dump_stack();
692 return;
693 }
694
695 if (neigh_del_timer(neigh))
696 pr_warn("Impossible event\n");
697
698 write_lock_bh(&neigh->lock);
699 __skb_queue_purge(&neigh->arp_queue);
700 write_unlock_bh(&neigh->lock);
701 neigh->arp_queue_len_bytes = 0;
702
703 if (dev->netdev_ops->ndo_neigh_destroy)
704 dev->netdev_ops->ndo_neigh_destroy(neigh);
705
706 dev_put(dev);
707 neigh_parms_put(neigh->parms);
708
709 neigh_dbg(2, "neigh %p is destroyed\n", neigh);
710
711 atomic_dec(&neigh->tbl->entries);
712 kfree_rcu(neigh, rcu);
713}
714EXPORT_SYMBOL(neigh_destroy);
715
716/* Neighbour state is suspicious;
717 disable fast path.
718
719 Called with write_locked neigh.
720 */
721static void neigh_suspect(struct neighbour *neigh)
722{
723 neigh_dbg(2, "neigh %p is suspected\n", neigh);
724
725 neigh->output = neigh->ops->output;
726}
727
728/* Neighbour state is OK;
729 enable fast path.
730
731 Called with write_locked neigh.
732 */
733static void neigh_connect(struct neighbour *neigh)
734{
735 neigh_dbg(2, "neigh %p is connected\n", neigh);
736
737 neigh->output = neigh->ops->connected_output;
738}
739
740static void neigh_periodic_work(struct work_struct *work)
741{
742 struct neigh_table *tbl = container_of(work, struct neigh_table, gc_work.work);
743 struct neighbour *n;
744 struct neighbour __rcu **np;
745 unsigned int i;
746 struct neigh_hash_table *nht;
747
748 NEIGH_CACHE_STAT_INC(tbl, periodic_gc_runs);
749
750 write_lock_bh(&tbl->lock);
751 nht = rcu_dereference_protected(tbl->nht,
752 lockdep_is_held(&tbl->lock));
753
754 /*
755 * periodically recompute ReachableTime from random function
756 */
757
758 if (time_after(jiffies, tbl->last_rand + 300 * HZ)) {
759 struct neigh_parms *p;
760 tbl->last_rand = jiffies;
761 list_for_each_entry(p, &tbl->parms_list, list)
762 p->reachable_time =
763 neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME));
764 }
765
766 if (atomic_read(&tbl->entries) < tbl->gc_thresh1)
767 goto out;
768
769 for (i = 0 ; i < (1 << nht->hash_shift); i++) {
770 np = &nht->hash_buckets[i];
771
772 while ((n = rcu_dereference_protected(*np,
773 lockdep_is_held(&tbl->lock))) != NULL) {
774 unsigned int state;
775
776 write_lock(&n->lock);
777
778 state = n->nud_state;
779 if (state & (NUD_PERMANENT | NUD_IN_TIMER)) {
780 write_unlock(&n->lock);
781 goto next_elt;
782 }
783
784 if (time_before(n->used, n->confirmed))
785 n->used = n->confirmed;
786
787 if (atomic_read(&n->refcnt) == 1 &&
788 (state == NUD_FAILED ||
789 time_after(jiffies, n->used + NEIGH_VAR(n->parms, GC_STALETIME)))) {
790 *np = n->next;
791 n->dead = 1;
792 write_unlock(&n->lock);
793 neigh_cleanup_and_release(n);
794 continue;
795 }
796 write_unlock(&n->lock);
797
798next_elt:
799 np = &n->next;
800 }
801 /*
802 * It's fine to release lock here, even if hash table
803 * grows while we are preempted.
804 */
805 write_unlock_bh(&tbl->lock);
806 cond_resched();
807 write_lock_bh(&tbl->lock);
808 nht = rcu_dereference_protected(tbl->nht,
809 lockdep_is_held(&tbl->lock));
810 }
811out:
812 /* Cycle through all hash buckets every BASE_REACHABLE_TIME/2 ticks.
813 * ARP entry timeouts range from 1/2 BASE_REACHABLE_TIME to 3/2
814 * BASE_REACHABLE_TIME.
815 */
816 queue_delayed_work(system_power_efficient_wq, &tbl->gc_work,
817 NEIGH_VAR(&tbl->parms, BASE_REACHABLE_TIME) >> 1);
818 write_unlock_bh(&tbl->lock);
819}
820
821static __inline__ int neigh_max_probes(struct neighbour *n)
822{
823 struct neigh_parms *p = n->parms;
824 return NEIGH_VAR(p, UCAST_PROBES) + NEIGH_VAR(p, APP_PROBES) +
825 (n->nud_state & NUD_PROBE ? NEIGH_VAR(p, MCAST_REPROBES) :
826 NEIGH_VAR(p, MCAST_PROBES));
827}
828
829static void neigh_invalidate(struct neighbour *neigh)
830 __releases(neigh->lock)
831 __acquires(neigh->lock)
832{
833 struct sk_buff *skb;
834
835 NEIGH_CACHE_STAT_INC(neigh->tbl, res_failed);
836 neigh_dbg(2, "neigh %p is failed\n", neigh);
837 neigh->updated = jiffies;
838
839 /* It is very thin place. report_unreachable is very complicated
840 routine. Particularly, it can hit the same neighbour entry!
841
842 So that, we try to be accurate and avoid dead loop. --ANK
843 */
844 while (neigh->nud_state == NUD_FAILED &&
845 (skb = __skb_dequeue(&neigh->arp_queue)) != NULL) {
846 write_unlock(&neigh->lock);
847 neigh->ops->error_report(neigh, skb);
848 write_lock(&neigh->lock);
849 }
850 __skb_queue_purge(&neigh->arp_queue);
851 neigh->arp_queue_len_bytes = 0;
852}
853
854static void neigh_probe(struct neighbour *neigh)
855 __releases(neigh->lock)
856{
857 struct sk_buff *skb = skb_peek_tail(&neigh->arp_queue);
858 /* keep skb alive even if arp_queue overflows */
859 if (skb)
860 skb = skb_clone(skb, GFP_ATOMIC);
861 write_unlock(&neigh->lock);
862 neigh->ops->solicit(neigh, skb);
863 atomic_inc(&neigh->probes);
864 kfree_skb(skb);
865}
866
867/* Called when a timer expires for a neighbour entry. */
868
869static void neigh_timer_handler(unsigned long arg)
870{
871 unsigned long now, next;
872 struct neighbour *neigh = (struct neighbour *)arg;
873 unsigned int state;
874 int notify = 0;
875
876 write_lock(&neigh->lock);
877
878 state = neigh->nud_state;
879 now = jiffies;
880 next = now + HZ;
881
882 if (!(state & NUD_IN_TIMER))
883 goto out;
884
885 if (state & NUD_REACHABLE) {
886 if (time_before_eq(now,
887 neigh->confirmed + neigh->parms->reachable_time)) {
888 neigh_dbg(2, "neigh %p is still alive\n", neigh);
889 next = neigh->confirmed + neigh->parms->reachable_time;
890 } else if (time_before_eq(now,
891 neigh->used +
892 NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME))) {
893 neigh_dbg(2, "neigh %p is delayed\n", neigh);
894 neigh->nud_state = NUD_DELAY;
895 neigh->updated = jiffies;
896 neigh_suspect(neigh);
897 next = now + NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME);
898 } else {
899 neigh_dbg(2, "neigh %p is suspected\n", neigh);
900 neigh->nud_state = NUD_STALE;
901 neigh->updated = jiffies;
902 neigh_suspect(neigh);
903 notify = 1;
904 }
905 } else if (state & NUD_DELAY) {
906 if (time_before_eq(now,
907 neigh->confirmed +
908 NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME))) {
909 neigh_dbg(2, "neigh %p is now reachable\n", neigh);
910 neigh->nud_state = NUD_REACHABLE;
911 neigh->updated = jiffies;
912 neigh_connect(neigh);
913 notify = 1;
914 next = neigh->confirmed + neigh->parms->reachable_time;
915 } else {
916 neigh_dbg(2, "neigh %p is probed\n", neigh);
917 neigh->nud_state = NUD_PROBE;
918 neigh->updated = jiffies;
919 atomic_set(&neigh->probes, 0);
920 notify = 1;
921 next = now + NEIGH_VAR(neigh->parms, RETRANS_TIME);
922 }
923 } else {
924 /* NUD_PROBE|NUD_INCOMPLETE */
925 next = now + NEIGH_VAR(neigh->parms, RETRANS_TIME);
926 }
927
928 if ((neigh->nud_state & (NUD_INCOMPLETE | NUD_PROBE)) &&
929 atomic_read(&neigh->probes) >= neigh_max_probes(neigh)) {
930 neigh->nud_state = NUD_FAILED;
931 notify = 1;
932 neigh_invalidate(neigh);
933 goto out;
934 }
935
936 if (neigh->nud_state & NUD_IN_TIMER) {
937 if (time_before(next, jiffies + HZ/2))
938 next = jiffies + HZ/2;
939 if (!mod_timer(&neigh->timer, next))
940 neigh_hold(neigh);
941 }
942 if (neigh->nud_state & (NUD_INCOMPLETE | NUD_PROBE)) {
943 neigh_probe(neigh);
944 } else {
945out:
946 write_unlock(&neigh->lock);
947 }
948
949 if (notify)
950 neigh_update_notify(neigh);
951
952 neigh_release(neigh);
953}
954
955int __neigh_event_send(struct neighbour *neigh, struct sk_buff *skb)
956{
957 int rc;
958 bool immediate_probe = false;
959
960 write_lock_bh(&neigh->lock);
961
962 rc = 0;
963 if (neigh->nud_state & (NUD_CONNECTED | NUD_DELAY | NUD_PROBE))
964 goto out_unlock_bh;
965 if (neigh->dead)
966 goto out_dead;
967
968 if (!(neigh->nud_state & (NUD_STALE | NUD_INCOMPLETE))) {
969 if (NEIGH_VAR(neigh->parms, MCAST_PROBES) +
970 NEIGH_VAR(neigh->parms, APP_PROBES)) {
971 unsigned long next, now = jiffies;
972
973 atomic_set(&neigh->probes,
974 NEIGH_VAR(neigh->parms, UCAST_PROBES));
975 neigh->nud_state = NUD_INCOMPLETE;
976 neigh->updated = now;
977 next = now + max(NEIGH_VAR(neigh->parms, RETRANS_TIME),
978 HZ/2);
979 neigh_add_timer(neigh, next);
980 immediate_probe = true;
981 } else {
982 neigh->nud_state = NUD_FAILED;
983 neigh->updated = jiffies;
984 write_unlock_bh(&neigh->lock);
985
986 kfree_skb(skb);
987 return 1;
988 }
989 } else if (neigh->nud_state & NUD_STALE) {
990 neigh_dbg(2, "neigh %p is delayed\n", neigh);
991 neigh->nud_state = NUD_DELAY;
992 neigh->updated = jiffies;
993 neigh_add_timer(neigh, jiffies +
994 NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME));
995 }
996
997 if (neigh->nud_state == NUD_INCOMPLETE) {
998 if (skb) {
999 while (neigh->arp_queue_len_bytes + skb->truesize >
1000 NEIGH_VAR(neigh->parms, QUEUE_LEN_BYTES)) {
1001 struct sk_buff *buff;
1002
1003 buff = __skb_dequeue(&neigh->arp_queue);
1004 if (!buff)
1005 break;
1006 neigh->arp_queue_len_bytes -= buff->truesize;
1007 kfree_skb(buff);
1008 NEIGH_CACHE_STAT_INC(neigh->tbl, unres_discards);
1009 }
1010 skb_dst_force(skb);
1011 __skb_queue_tail(&neigh->arp_queue, skb);
1012 neigh->arp_queue_len_bytes += skb->truesize;
1013 }
1014 rc = 1;
1015 }
1016out_unlock_bh:
1017 if (immediate_probe)
1018 neigh_probe(neigh);
1019 else
1020 write_unlock(&neigh->lock);
1021 local_bh_enable();
1022 return rc;
1023
1024out_dead:
1025 if (neigh->nud_state & NUD_STALE)
1026 goto out_unlock_bh;
1027 write_unlock_bh(&neigh->lock);
1028 kfree_skb(skb);
1029 return 1;
1030}
1031EXPORT_SYMBOL(__neigh_event_send);
1032
1033static void neigh_update_hhs(struct neighbour *neigh)
1034{
1035 struct hh_cache *hh;
1036 void (*update)(struct hh_cache*, const struct net_device*, const unsigned char *)
1037 = NULL;
1038
1039 if (neigh->dev->header_ops)
1040 update = neigh->dev->header_ops->cache_update;
1041
1042 if (update) {
1043 hh = &neigh->hh;
1044 if (hh->hh_len) {
1045 write_seqlock_bh(&hh->hh_lock);
1046 update(hh, neigh->dev, neigh->ha);
1047 write_sequnlock_bh(&hh->hh_lock);
1048 }
1049 }
1050}
1051
1052
1053
1054/* Generic update routine.
1055 -- lladdr is new lladdr or NULL, if it is not supplied.
1056 -- new is new state.
1057 -- flags
1058 NEIGH_UPDATE_F_OVERRIDE allows to override existing lladdr,
1059 if it is different.
1060 NEIGH_UPDATE_F_WEAK_OVERRIDE will suspect existing "connected"
1061 lladdr instead of overriding it
1062 if it is different.
1063 It also allows to retain current state
1064 if lladdr is unchanged.
1065 NEIGH_UPDATE_F_ADMIN means that the change is administrative.
1066
1067 NEIGH_UPDATE_F_OVERRIDE_ISROUTER allows to override existing
1068 NTF_ROUTER flag.
1069 NEIGH_UPDATE_F_ISROUTER indicates if the neighbour is known as
1070 a router.
1071
1072 Caller MUST hold reference count on the entry.
1073 */
1074
1075int neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new,
1076 u32 flags)
1077{
1078 u8 old;
1079 int err;
1080 int notify = 0;
1081 struct net_device *dev;
1082 int update_isrouter = 0;
1083
1084 write_lock_bh(&neigh->lock);
1085
1086 dev = neigh->dev;
1087 old = neigh->nud_state;
1088 err = -EPERM;
1089
1090 if (!(flags & NEIGH_UPDATE_F_ADMIN) &&
1091 (old & (NUD_NOARP | NUD_PERMANENT)))
1092 goto out;
1093 if (neigh->dead)
1094 goto out;
1095
1096 if (!(new & NUD_VALID)) {
1097 neigh_del_timer(neigh);
1098 if (old & NUD_CONNECTED)
1099 neigh_suspect(neigh);
1100 neigh->nud_state = new;
1101 err = 0;
1102 notify = old & NUD_VALID;
1103 if ((old & (NUD_INCOMPLETE | NUD_PROBE)) &&
1104 (new & NUD_FAILED)) {
1105 neigh_invalidate(neigh);
1106 notify = 1;
1107 }
1108 goto out;
1109 }
1110
1111 /* Compare new lladdr with cached one */
1112 if (!dev->addr_len) {
1113 /* First case: device needs no address. */
1114 lladdr = neigh->ha;
1115 } else if (lladdr) {
1116 /* The second case: if something is already cached
1117 and a new address is proposed:
1118 - compare new & old
1119 - if they are different, check override flag
1120 */
1121 if ((old & NUD_VALID) &&
1122 !memcmp(lladdr, neigh->ha, dev->addr_len))
1123 lladdr = neigh->ha;
1124 } else {
1125 /* No address is supplied; if we know something,
1126 use it, otherwise discard the request.
1127 */
1128 err = -EINVAL;
1129 if (!(old & NUD_VALID))
1130 goto out;
1131 lladdr = neigh->ha;
1132 }
1133
1134 if (new & NUD_CONNECTED)
1135 neigh->confirmed = jiffies;
1136 neigh->updated = jiffies;
1137
1138 /* If entry was valid and address is not changed,
1139 do not change entry state, if new one is STALE.
1140 */
1141 err = 0;
1142 update_isrouter = flags & NEIGH_UPDATE_F_OVERRIDE_ISROUTER;
1143 if (old & NUD_VALID) {
1144 if (lladdr != neigh->ha && !(flags & NEIGH_UPDATE_F_OVERRIDE)) {
1145 update_isrouter = 0;
1146 if ((flags & NEIGH_UPDATE_F_WEAK_OVERRIDE) &&
1147 (old & NUD_CONNECTED)) {
1148 lladdr = neigh->ha;
1149 new = NUD_STALE;
1150 } else
1151 goto out;
1152 } else {
1153 if (lladdr == neigh->ha && new == NUD_STALE &&
1154 ((flags & NEIGH_UPDATE_F_WEAK_OVERRIDE) ||
1155 (old & NUD_CONNECTED))
1156 )
1157 new = old;
1158 }
1159 }
1160
1161 if (new != old) {
1162 neigh_del_timer(neigh);
1163 if (new & NUD_PROBE)
1164 atomic_set(&neigh->probes, 0);
1165 if (new & NUD_IN_TIMER)
1166 neigh_add_timer(neigh, (jiffies +
1167 ((new & NUD_REACHABLE) ?
1168 neigh->parms->reachable_time :
1169 0)));
1170 neigh->nud_state = new;
1171 notify = 1;
1172 }
1173
1174 if (lladdr != neigh->ha) {
1175 write_seqlock(&neigh->ha_lock);
1176 memcpy(&neigh->ha, lladdr, dev->addr_len);
1177 write_sequnlock(&neigh->ha_lock);
1178 neigh_update_hhs(neigh);
1179 if (!(new & NUD_CONNECTED))
1180 neigh->confirmed = jiffies -
1181 (NEIGH_VAR(neigh->parms, BASE_REACHABLE_TIME) << 1);
1182 notify = 1;
1183 }
1184 if (new == old)
1185 goto out;
1186 if (new & NUD_CONNECTED)
1187 neigh_connect(neigh);
1188 else
1189 neigh_suspect(neigh);
1190 if (!(old & NUD_VALID)) {
1191 struct sk_buff *skb;
1192
1193 /* Again: avoid dead loop if something went wrong */
1194
1195 while (neigh->nud_state & NUD_VALID &&
1196 (skb = __skb_dequeue(&neigh->arp_queue)) != NULL) {
1197 struct dst_entry *dst = skb_dst(skb);
1198 struct neighbour *n2, *n1 = neigh;
1199 write_unlock_bh(&neigh->lock);
1200
1201 rcu_read_lock();
1202
1203 /* Why not just use 'neigh' as-is? The problem is that
1204 * things such as shaper, eql, and sch_teql can end up
1205 * using alternative, different, neigh objects to output
1206 * the packet in the output path. So what we need to do
1207 * here is re-lookup the top-level neigh in the path so
1208 * we can reinject the packet there.
1209 */
1210 n2 = NULL;
1211 if (dst) {
1212 n2 = dst_neigh_lookup_skb(dst, skb);
1213 if (n2)
1214 n1 = n2;
1215 }
1216 n1->output(n1, skb);
1217 if (n2)
1218 neigh_release(n2);
1219 rcu_read_unlock();
1220
1221 write_lock_bh(&neigh->lock);
1222 }
1223 __skb_queue_purge(&neigh->arp_queue);
1224 neigh->arp_queue_len_bytes = 0;
1225 }
1226out:
1227 if (update_isrouter) {
1228 neigh->flags = (flags & NEIGH_UPDATE_F_ISROUTER) ?
1229 (neigh->flags | NTF_ROUTER) :
1230 (neigh->flags & ~NTF_ROUTER);
1231 }
1232 write_unlock_bh(&neigh->lock);
1233
1234 if (notify)
1235 neigh_update_notify(neigh);
1236
1237 return err;
1238}
1239EXPORT_SYMBOL(neigh_update);
1240
1241/* Update the neigh to listen temporarily for probe responses, even if it is
1242 * in a NUD_FAILED state. The caller has to hold neigh->lock for writing.
1243 */
1244void __neigh_set_probe_once(struct neighbour *neigh)
1245{
1246 if (neigh->dead)
1247 return;
1248 neigh->updated = jiffies;
1249 if (!(neigh->nud_state & NUD_FAILED))
1250 return;
1251 neigh->nud_state = NUD_INCOMPLETE;
1252 atomic_set(&neigh->probes, neigh_max_probes(neigh));
1253 neigh_add_timer(neigh,
1254 jiffies + NEIGH_VAR(neigh->parms, RETRANS_TIME));
1255}
1256EXPORT_SYMBOL(__neigh_set_probe_once);
1257
1258struct neighbour *neigh_event_ns(struct neigh_table *tbl,
1259 u8 *lladdr, void *saddr,
1260 struct net_device *dev)
1261{
1262 struct neighbour *neigh = __neigh_lookup(tbl, saddr, dev,
1263 lladdr || !dev->addr_len);
1264 if (neigh)
1265 neigh_update(neigh, lladdr, NUD_STALE,
1266 NEIGH_UPDATE_F_OVERRIDE);
1267 return neigh;
1268}
1269EXPORT_SYMBOL(neigh_event_ns);
1270
1271/* called with read_lock_bh(&n->lock); */
1272static void neigh_hh_init(struct neighbour *n)
1273{
1274 struct net_device *dev = n->dev;
1275 __be16 prot = n->tbl->protocol;
1276 struct hh_cache *hh = &n->hh;
1277
1278 write_lock_bh(&n->lock);
1279
1280 /* Only one thread can come in here and initialize the
1281 * hh_cache entry.
1282 */
1283 if (!hh->hh_len)
1284 dev->header_ops->cache(n, hh, prot);
1285
1286 write_unlock_bh(&n->lock);
1287}
1288
1289/* Slow and careful. */
1290
1291int neigh_resolve_output(struct neighbour *neigh, struct sk_buff *skb)
1292{
1293 int rc = 0;
1294
1295 if (!neigh_event_send(neigh, skb)) {
1296 int err;
1297 struct net_device *dev = neigh->dev;
1298 unsigned int seq;
1299
1300 if (dev->header_ops->cache && !neigh->hh.hh_len)
1301 neigh_hh_init(neigh);
1302
1303 do {
1304 __skb_pull(skb, skb_network_offset(skb));
1305 seq = read_seqbegin(&neigh->ha_lock);
1306 err = dev_hard_header(skb, dev, ntohs(skb->protocol),
1307 neigh->ha, NULL, skb->len);
1308 } while (read_seqretry(&neigh->ha_lock, seq));
1309
1310 if (err >= 0)
1311 rc = dev_queue_xmit(skb);
1312 else
1313 goto out_kfree_skb;
1314 }
1315out:
1316 return rc;
1317out_kfree_skb:
1318 rc = -EINVAL;
1319 kfree_skb(skb);
1320 goto out;
1321}
1322EXPORT_SYMBOL(neigh_resolve_output);
1323
1324/* As fast as possible without hh cache */
1325
1326int neigh_connected_output(struct neighbour *neigh, struct sk_buff *skb)
1327{
1328 struct net_device *dev = neigh->dev;
1329 unsigned int seq;
1330 int err;
1331
1332 do {
1333 __skb_pull(skb, skb_network_offset(skb));
1334 seq = read_seqbegin(&neigh->ha_lock);
1335 err = dev_hard_header(skb, dev, ntohs(skb->protocol),
1336 neigh->ha, NULL, skb->len);
1337 } while (read_seqretry(&neigh->ha_lock, seq));
1338
1339 if (err >= 0)
1340 err = dev_queue_xmit(skb);
1341 else {
1342 err = -EINVAL;
1343 kfree_skb(skb);
1344 }
1345 return err;
1346}
1347EXPORT_SYMBOL(neigh_connected_output);
1348
1349int neigh_direct_output(struct neighbour *neigh, struct sk_buff *skb)
1350{
1351 return dev_queue_xmit(skb);
1352}
1353EXPORT_SYMBOL(neigh_direct_output);
1354
1355static void neigh_proxy_process(unsigned long arg)
1356{
1357 struct neigh_table *tbl = (struct neigh_table *)arg;
1358 long sched_next = 0;
1359 unsigned long now = jiffies;
1360 struct sk_buff *skb, *n;
1361
1362 spin_lock(&tbl->proxy_queue.lock);
1363
1364 skb_queue_walk_safe(&tbl->proxy_queue, skb, n) {
1365 long tdif = NEIGH_CB(skb)->sched_next - now;
1366
1367 if (tdif <= 0) {
1368 struct net_device *dev = skb->dev;
1369
1370 __skb_unlink(skb, &tbl->proxy_queue);
1371 if (tbl->proxy_redo && netif_running(dev)) {
1372 rcu_read_lock();
1373 tbl->proxy_redo(skb);
1374 rcu_read_unlock();
1375 } else {
1376 kfree_skb(skb);
1377 }
1378
1379 dev_put(dev);
1380 } else if (!sched_next || tdif < sched_next)
1381 sched_next = tdif;
1382 }
1383 del_timer(&tbl->proxy_timer);
1384 if (sched_next)
1385 mod_timer(&tbl->proxy_timer, jiffies + sched_next);
1386 spin_unlock(&tbl->proxy_queue.lock);
1387}
1388
1389void pneigh_enqueue(struct neigh_table *tbl, struct neigh_parms *p,
1390 struct sk_buff *skb)
1391{
1392 unsigned long now = jiffies;
1393
1394 unsigned long sched_next = now + (prandom_u32() %
1395 NEIGH_VAR(p, PROXY_DELAY));
1396
1397 if (tbl->proxy_queue.qlen > NEIGH_VAR(p, PROXY_QLEN)) {
1398 kfree_skb(skb);
1399 return;
1400 }
1401
1402 NEIGH_CB(skb)->sched_next = sched_next;
1403 NEIGH_CB(skb)->flags |= LOCALLY_ENQUEUED;
1404
1405 spin_lock(&tbl->proxy_queue.lock);
1406 if (del_timer(&tbl->proxy_timer)) {
1407 if (time_before(tbl->proxy_timer.expires, sched_next))
1408 sched_next = tbl->proxy_timer.expires;
1409 }
1410 skb_dst_drop(skb);
1411 dev_hold(skb->dev);
1412 __skb_queue_tail(&tbl->proxy_queue, skb);
1413 mod_timer(&tbl->proxy_timer, sched_next);
1414 spin_unlock(&tbl->proxy_queue.lock);
1415}
1416EXPORT_SYMBOL(pneigh_enqueue);
1417
1418static inline struct neigh_parms *lookup_neigh_parms(struct neigh_table *tbl,
1419 struct net *net, int ifindex)
1420{
1421 struct neigh_parms *p;
1422
1423 list_for_each_entry(p, &tbl->parms_list, list) {
1424 if ((p->dev && p->dev->ifindex == ifindex && net_eq(neigh_parms_net(p), net)) ||
1425 (!p->dev && !ifindex && net_eq(net, &init_net)))
1426 return p;
1427 }
1428
1429 return NULL;
1430}
1431
1432struct neigh_parms *neigh_parms_alloc(struct net_device *dev,
1433 struct neigh_table *tbl)
1434{
1435 struct neigh_parms *p;
1436 struct net *net = dev_net(dev);
1437 const struct net_device_ops *ops = dev->netdev_ops;
1438
1439 p = kmemdup(&tbl->parms, sizeof(*p), GFP_KERNEL);
1440 if (p) {
1441 p->tbl = tbl;
1442 atomic_set(&p->refcnt, 1);
1443 p->reachable_time =
1444 neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME));
1445 dev_hold(dev);
1446 p->dev = dev;
1447 write_pnet(&p->net, net);
1448 p->sysctl_table = NULL;
1449
1450 if (ops->ndo_neigh_setup && ops->ndo_neigh_setup(dev, p)) {
1451 dev_put(dev);
1452 kfree(p);
1453 return NULL;
1454 }
1455
1456 write_lock_bh(&tbl->lock);
1457 list_add(&p->list, &tbl->parms.list);
1458 write_unlock_bh(&tbl->lock);
1459
1460 neigh_parms_data_state_cleanall(p);
1461 }
1462 return p;
1463}
1464EXPORT_SYMBOL(neigh_parms_alloc);
1465
1466static void neigh_rcu_free_parms(struct rcu_head *head)
1467{
1468 struct neigh_parms *parms =
1469 container_of(head, struct neigh_parms, rcu_head);
1470
1471 neigh_parms_put(parms);
1472}
1473
1474void neigh_parms_release(struct neigh_table *tbl, struct neigh_parms *parms)
1475{
1476 if (!parms || parms == &tbl->parms)
1477 return;
1478 write_lock_bh(&tbl->lock);
1479 list_del(&parms->list);
1480 parms->dead = 1;
1481 write_unlock_bh(&tbl->lock);
1482 if (parms->dev)
1483 dev_put(parms->dev);
1484 call_rcu(&parms->rcu_head, neigh_rcu_free_parms);
1485}
1486EXPORT_SYMBOL(neigh_parms_release);
1487
1488static void neigh_parms_destroy(struct neigh_parms *parms)
1489{
1490 kfree(parms);
1491}
1492
1493static struct lock_class_key neigh_table_proxy_queue_class;
1494
1495static struct neigh_table *neigh_tables[NEIGH_NR_TABLES] __read_mostly;
1496
1497void neigh_table_init(int index, struct neigh_table *tbl)
1498{
1499 unsigned long now = jiffies;
1500 unsigned long phsize;
1501
1502 INIT_LIST_HEAD(&tbl->parms_list);
1503 list_add(&tbl->parms.list, &tbl->parms_list);
1504 write_pnet(&tbl->parms.net, &init_net);
1505 atomic_set(&tbl->parms.refcnt, 1);
1506 tbl->parms.reachable_time =
1507 neigh_rand_reach_time(NEIGH_VAR(&tbl->parms, BASE_REACHABLE_TIME));
1508
1509 tbl->stats = alloc_percpu(struct neigh_statistics);
1510 if (!tbl->stats)
1511 panic("cannot create neighbour cache statistics");
1512
1513#ifdef CONFIG_PROC_FS
1514 if (!proc_create_data(tbl->id, 0, init_net.proc_net_stat,
1515 &neigh_stat_seq_fops, tbl))
1516 panic("cannot create neighbour proc dir entry");
1517#endif
1518
1519 RCU_INIT_POINTER(tbl->nht, neigh_hash_alloc(3));
1520
1521 phsize = (PNEIGH_HASHMASK + 1) * sizeof(struct pneigh_entry *);
1522 tbl->phash_buckets = kzalloc(phsize, GFP_KERNEL);
1523
1524 if (!tbl->nht || !tbl->phash_buckets)
1525 panic("cannot allocate neighbour cache hashes");
1526
1527 if (!tbl->entry_size)
1528 tbl->entry_size = ALIGN(offsetof(struct neighbour, primary_key) +
1529 tbl->key_len, NEIGH_PRIV_ALIGN);
1530 else
1531 WARN_ON(tbl->entry_size % NEIGH_PRIV_ALIGN);
1532
1533 rwlock_init(&tbl->lock);
1534 INIT_DEFERRABLE_WORK(&tbl->gc_work, neigh_periodic_work);
1535 queue_delayed_work(system_power_efficient_wq, &tbl->gc_work,
1536 tbl->parms.reachable_time);
1537 setup_timer(&tbl->proxy_timer, neigh_proxy_process, (unsigned long)tbl);
1538 skb_queue_head_init_class(&tbl->proxy_queue,
1539 &neigh_table_proxy_queue_class);
1540
1541 tbl->last_flush = now;
1542 tbl->last_rand = now + tbl->parms.reachable_time * 20;
1543
1544 neigh_tables[index] = tbl;
1545}
1546EXPORT_SYMBOL(neigh_table_init);
1547
1548int neigh_table_clear(int index, struct neigh_table *tbl)
1549{
1550 neigh_tables[index] = NULL;
1551 /* It is not clean... Fix it to unload IPv6 module safely */
1552 cancel_delayed_work_sync(&tbl->gc_work);
1553 del_timer_sync(&tbl->proxy_timer);
1554 pneigh_queue_purge(&tbl->proxy_queue);
1555 neigh_ifdown(tbl, NULL);
1556 if (atomic_read(&tbl->entries))
1557 pr_crit("neighbour leakage\n");
1558
1559 call_rcu(&rcu_dereference_protected(tbl->nht, 1)->rcu,
1560 neigh_hash_free_rcu);
1561 tbl->nht = NULL;
1562
1563 kfree(tbl->phash_buckets);
1564 tbl->phash_buckets = NULL;
1565
1566 remove_proc_entry(tbl->id, init_net.proc_net_stat);
1567
1568 free_percpu(tbl->stats);
1569 tbl->stats = NULL;
1570
1571 return 0;
1572}
1573EXPORT_SYMBOL(neigh_table_clear);
1574
1575static struct neigh_table *neigh_find_table(int family)
1576{
1577 struct neigh_table *tbl = NULL;
1578
1579 switch (family) {
1580 case AF_INET:
1581 tbl = neigh_tables[NEIGH_ARP_TABLE];
1582 break;
1583 case AF_INET6:
1584 tbl = neigh_tables[NEIGH_ND_TABLE];
1585 break;
1586 case AF_DECnet:
1587 tbl = neigh_tables[NEIGH_DN_TABLE];
1588 break;
1589 }
1590
1591 return tbl;
1592}
1593
1594static int neigh_delete(struct sk_buff *skb, struct nlmsghdr *nlh)
1595{
1596 struct net *net = sock_net(skb->sk);
1597 struct ndmsg *ndm;
1598 struct nlattr *dst_attr;
1599 struct neigh_table *tbl;
1600 struct neighbour *neigh;
1601 struct net_device *dev = NULL;
1602 int err = -EINVAL;
1603
1604 ASSERT_RTNL();
1605 if (nlmsg_len(nlh) < sizeof(*ndm))
1606 goto out;
1607
1608 dst_attr = nlmsg_find_attr(nlh, sizeof(*ndm), NDA_DST);
1609 if (dst_attr == NULL)
1610 goto out;
1611
1612 ndm = nlmsg_data(nlh);
1613 if (ndm->ndm_ifindex) {
1614 dev = __dev_get_by_index(net, ndm->ndm_ifindex);
1615 if (dev == NULL) {
1616 err = -ENODEV;
1617 goto out;
1618 }
1619 }
1620
1621 tbl = neigh_find_table(ndm->ndm_family);
1622 if (tbl == NULL)
1623 return -EAFNOSUPPORT;
1624
1625 if (nla_len(dst_attr) < tbl->key_len)
1626 goto out;
1627
1628 if (ndm->ndm_flags & NTF_PROXY) {
1629 err = pneigh_delete(tbl, net, nla_data(dst_attr), dev);
1630 goto out;
1631 }
1632
1633 if (dev == NULL)
1634 goto out;
1635
1636 neigh = neigh_lookup(tbl, nla_data(dst_attr), dev);
1637 if (neigh == NULL) {
1638 err = -ENOENT;
1639 goto out;
1640 }
1641
1642 err = neigh_update(neigh, NULL, NUD_FAILED,
1643 NEIGH_UPDATE_F_OVERRIDE |
1644 NEIGH_UPDATE_F_ADMIN);
1645 neigh_release(neigh);
1646
1647out:
1648 return err;
1649}
1650
1651static int neigh_add(struct sk_buff *skb, struct nlmsghdr *nlh)
1652{
1653 int flags = NEIGH_UPDATE_F_ADMIN | NEIGH_UPDATE_F_OVERRIDE;
1654 struct net *net = sock_net(skb->sk);
1655 struct ndmsg *ndm;
1656 struct nlattr *tb[NDA_MAX+1];
1657 struct neigh_table *tbl;
1658 struct net_device *dev = NULL;
1659 struct neighbour *neigh;
1660 void *dst, *lladdr;
1661 int err;
1662
1663 ASSERT_RTNL();
1664 err = nlmsg_parse(nlh, sizeof(*ndm), tb, NDA_MAX, NULL);
1665 if (err < 0)
1666 goto out;
1667
1668 err = -EINVAL;
1669 if (tb[NDA_DST] == NULL)
1670 goto out;
1671
1672 ndm = nlmsg_data(nlh);
1673 if (ndm->ndm_ifindex) {
1674 dev = __dev_get_by_index(net, ndm->ndm_ifindex);
1675 if (dev == NULL) {
1676 err = -ENODEV;
1677 goto out;
1678 }
1679
1680 if (tb[NDA_LLADDR] && nla_len(tb[NDA_LLADDR]) < dev->addr_len)
1681 goto out;
1682 }
1683
1684 tbl = neigh_find_table(ndm->ndm_family);
1685 if (tbl == NULL)
1686 return -EAFNOSUPPORT;
1687
1688 if (nla_len(tb[NDA_DST]) < tbl->key_len)
1689 goto out;
1690 dst = nla_data(tb[NDA_DST]);
1691 lladdr = tb[NDA_LLADDR] ? nla_data(tb[NDA_LLADDR]) : NULL;
1692
1693 if (ndm->ndm_flags & NTF_PROXY) {
1694 struct pneigh_entry *pn;
1695
1696 err = -ENOBUFS;
1697 pn = pneigh_lookup(tbl, net, dst, dev, 1);
1698 if (pn) {
1699 pn->flags = ndm->ndm_flags;
1700 err = 0;
1701 }
1702 goto out;
1703 }
1704
1705 if (dev == NULL)
1706 goto out;
1707
1708 neigh = neigh_lookup(tbl, dst, dev);
1709 if (neigh == NULL) {
1710 if (!(nlh->nlmsg_flags & NLM_F_CREATE)) {
1711 err = -ENOENT;
1712 goto out;
1713 }
1714
1715 neigh = __neigh_lookup_errno(tbl, dst, dev);
1716 if (IS_ERR(neigh)) {
1717 err = PTR_ERR(neigh);
1718 goto out;
1719 }
1720 } else {
1721 if (nlh->nlmsg_flags & NLM_F_EXCL) {
1722 err = -EEXIST;
1723 neigh_release(neigh);
1724 goto out;
1725 }
1726
1727 if (!(nlh->nlmsg_flags & NLM_F_REPLACE))
1728 flags &= ~NEIGH_UPDATE_F_OVERRIDE;
1729 }
1730
1731 if (ndm->ndm_flags & NTF_USE) {
1732 neigh_event_send(neigh, NULL);
1733 err = 0;
1734 } else
1735 err = neigh_update(neigh, lladdr, ndm->ndm_state, flags);
1736 neigh_release(neigh);
1737
1738out:
1739 return err;
1740}
1741
1742static int neightbl_fill_parms(struct sk_buff *skb, struct neigh_parms *parms)
1743{
1744 struct nlattr *nest;
1745
1746 nest = nla_nest_start(skb, NDTA_PARMS);
1747 if (nest == NULL)
1748 return -ENOBUFS;
1749
1750 if ((parms->dev &&
1751 nla_put_u32(skb, NDTPA_IFINDEX, parms->dev->ifindex)) ||
1752 nla_put_u32(skb, NDTPA_REFCNT, atomic_read(&parms->refcnt)) ||
1753 nla_put_u32(skb, NDTPA_QUEUE_LENBYTES,
1754 NEIGH_VAR(parms, QUEUE_LEN_BYTES)) ||
1755 /* approximative value for deprecated QUEUE_LEN (in packets) */
1756 nla_put_u32(skb, NDTPA_QUEUE_LEN,
1757 NEIGH_VAR(parms, QUEUE_LEN_BYTES) / SKB_TRUESIZE(ETH_FRAME_LEN)) ||
1758 nla_put_u32(skb, NDTPA_PROXY_QLEN, NEIGH_VAR(parms, PROXY_QLEN)) ||
1759 nla_put_u32(skb, NDTPA_APP_PROBES, NEIGH_VAR(parms, APP_PROBES)) ||
1760 nla_put_u32(skb, NDTPA_UCAST_PROBES,
1761 NEIGH_VAR(parms, UCAST_PROBES)) ||
1762 nla_put_u32(skb, NDTPA_MCAST_PROBES,
1763 NEIGH_VAR(parms, MCAST_PROBES)) ||
1764 nla_put_u32(skb, NDTPA_MCAST_REPROBES,
1765 NEIGH_VAR(parms, MCAST_REPROBES)) ||
1766 nla_put_msecs(skb, NDTPA_REACHABLE_TIME, parms->reachable_time) ||
1767 nla_put_msecs(skb, NDTPA_BASE_REACHABLE_TIME,
1768 NEIGH_VAR(parms, BASE_REACHABLE_TIME)) ||
1769 nla_put_msecs(skb, NDTPA_GC_STALETIME,
1770 NEIGH_VAR(parms, GC_STALETIME)) ||
1771 nla_put_msecs(skb, NDTPA_DELAY_PROBE_TIME,
1772 NEIGH_VAR(parms, DELAY_PROBE_TIME)) ||
1773 nla_put_msecs(skb, NDTPA_RETRANS_TIME,
1774 NEIGH_VAR(parms, RETRANS_TIME)) ||
1775 nla_put_msecs(skb, NDTPA_ANYCAST_DELAY,
1776 NEIGH_VAR(parms, ANYCAST_DELAY)) ||
1777 nla_put_msecs(skb, NDTPA_PROXY_DELAY,
1778 NEIGH_VAR(parms, PROXY_DELAY)) ||
1779 nla_put_msecs(skb, NDTPA_LOCKTIME,
1780 NEIGH_VAR(parms, LOCKTIME)))
1781 goto nla_put_failure;
1782 return nla_nest_end(skb, nest);
1783
1784nla_put_failure:
1785 nla_nest_cancel(skb, nest);
1786 return -EMSGSIZE;
1787}
1788
1789static int neightbl_fill_info(struct sk_buff *skb, struct neigh_table *tbl,
1790 u32 pid, u32 seq, int type, int flags)
1791{
1792 struct nlmsghdr *nlh;
1793 struct ndtmsg *ndtmsg;
1794
1795 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndtmsg), flags);
1796 if (nlh == NULL)
1797 return -EMSGSIZE;
1798
1799 ndtmsg = nlmsg_data(nlh);
1800
1801 read_lock_bh(&tbl->lock);
1802 ndtmsg->ndtm_family = tbl->family;
1803 ndtmsg->ndtm_pad1 = 0;
1804 ndtmsg->ndtm_pad2 = 0;
1805
1806 if (nla_put_string(skb, NDTA_NAME, tbl->id) ||
1807 nla_put_msecs(skb, NDTA_GC_INTERVAL, tbl->gc_interval) ||
1808 nla_put_u32(skb, NDTA_THRESH1, tbl->gc_thresh1) ||
1809 nla_put_u32(skb, NDTA_THRESH2, tbl->gc_thresh2) ||
1810 nla_put_u32(skb, NDTA_THRESH3, tbl->gc_thresh3))
1811 goto nla_put_failure;
1812 {
1813 unsigned long now = jiffies;
1814 unsigned int flush_delta = now - tbl->last_flush;
1815 unsigned int rand_delta = now - tbl->last_rand;
1816 struct neigh_hash_table *nht;
1817 struct ndt_config ndc = {
1818 .ndtc_key_len = tbl->key_len,
1819 .ndtc_entry_size = tbl->entry_size,
1820 .ndtc_entries = atomic_read(&tbl->entries),
1821 .ndtc_last_flush = jiffies_to_msecs(flush_delta),
1822 .ndtc_last_rand = jiffies_to_msecs(rand_delta),
1823 .ndtc_proxy_qlen = tbl->proxy_queue.qlen,
1824 };
1825
1826 rcu_read_lock_bh();
1827 nht = rcu_dereference_bh(tbl->nht);
1828 ndc.ndtc_hash_rnd = nht->hash_rnd[0];
1829 ndc.ndtc_hash_mask = ((1 << nht->hash_shift) - 1);
1830 rcu_read_unlock_bh();
1831
1832 if (nla_put(skb, NDTA_CONFIG, sizeof(ndc), &ndc))
1833 goto nla_put_failure;
1834 }
1835
1836 {
1837 int cpu;
1838 struct ndt_stats ndst;
1839
1840 memset(&ndst, 0, sizeof(ndst));
1841
1842 for_each_possible_cpu(cpu) {
1843 struct neigh_statistics *st;
1844
1845 st = per_cpu_ptr(tbl->stats, cpu);
1846 ndst.ndts_allocs += st->allocs;
1847 ndst.ndts_destroys += st->destroys;
1848 ndst.ndts_hash_grows += st->hash_grows;
1849 ndst.ndts_res_failed += st->res_failed;
1850 ndst.ndts_lookups += st->lookups;
1851 ndst.ndts_hits += st->hits;
1852 ndst.ndts_rcv_probes_mcast += st->rcv_probes_mcast;
1853 ndst.ndts_rcv_probes_ucast += st->rcv_probes_ucast;
1854 ndst.ndts_periodic_gc_runs += st->periodic_gc_runs;
1855 ndst.ndts_forced_gc_runs += st->forced_gc_runs;
1856 ndst.ndts_table_fulls += st->table_fulls;
1857 }
1858
1859 if (nla_put(skb, NDTA_STATS, sizeof(ndst), &ndst))
1860 goto nla_put_failure;
1861 }
1862
1863 BUG_ON(tbl->parms.dev);
1864 if (neightbl_fill_parms(skb, &tbl->parms) < 0)
1865 goto nla_put_failure;
1866
1867 read_unlock_bh(&tbl->lock);
1868 nlmsg_end(skb, nlh);
1869 return 0;
1870
1871nla_put_failure:
1872 read_unlock_bh(&tbl->lock);
1873 nlmsg_cancel(skb, nlh);
1874 return -EMSGSIZE;
1875}
1876
1877static int neightbl_fill_param_info(struct sk_buff *skb,
1878 struct neigh_table *tbl,
1879 struct neigh_parms *parms,
1880 u32 pid, u32 seq, int type,
1881 unsigned int flags)
1882{
1883 struct ndtmsg *ndtmsg;
1884 struct nlmsghdr *nlh;
1885
1886 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndtmsg), flags);
1887 if (nlh == NULL)
1888 return -EMSGSIZE;
1889
1890 ndtmsg = nlmsg_data(nlh);
1891
1892 read_lock_bh(&tbl->lock);
1893 ndtmsg->ndtm_family = tbl->family;
1894 ndtmsg->ndtm_pad1 = 0;
1895 ndtmsg->ndtm_pad2 = 0;
1896
1897 if (nla_put_string(skb, NDTA_NAME, tbl->id) < 0 ||
1898 neightbl_fill_parms(skb, parms) < 0)
1899 goto errout;
1900
1901 read_unlock_bh(&tbl->lock);
1902 nlmsg_end(skb, nlh);
1903 return 0;
1904errout:
1905 read_unlock_bh(&tbl->lock);
1906 nlmsg_cancel(skb, nlh);
1907 return -EMSGSIZE;
1908}
1909
1910static const struct nla_policy nl_neightbl_policy[NDTA_MAX+1] = {
1911 [NDTA_NAME] = { .type = NLA_STRING },
1912 [NDTA_THRESH1] = { .type = NLA_U32 },
1913 [NDTA_THRESH2] = { .type = NLA_U32 },
1914 [NDTA_THRESH3] = { .type = NLA_U32 },
1915 [NDTA_GC_INTERVAL] = { .type = NLA_U64 },
1916 [NDTA_PARMS] = { .type = NLA_NESTED },
1917};
1918
1919static const struct nla_policy nl_ntbl_parm_policy[NDTPA_MAX+1] = {
1920 [NDTPA_IFINDEX] = { .type = NLA_U32 },
1921 [NDTPA_QUEUE_LEN] = { .type = NLA_U32 },
1922 [NDTPA_PROXY_QLEN] = { .type = NLA_U32 },
1923 [NDTPA_APP_PROBES] = { .type = NLA_U32 },
1924 [NDTPA_UCAST_PROBES] = { .type = NLA_U32 },
1925 [NDTPA_MCAST_PROBES] = { .type = NLA_U32 },
1926 [NDTPA_MCAST_REPROBES] = { .type = NLA_U32 },
1927 [NDTPA_BASE_REACHABLE_TIME] = { .type = NLA_U64 },
1928 [NDTPA_GC_STALETIME] = { .type = NLA_U64 },
1929 [NDTPA_DELAY_PROBE_TIME] = { .type = NLA_U64 },
1930 [NDTPA_RETRANS_TIME] = { .type = NLA_U64 },
1931 [NDTPA_ANYCAST_DELAY] = { .type = NLA_U64 },
1932 [NDTPA_PROXY_DELAY] = { .type = NLA_U64 },
1933 [NDTPA_LOCKTIME] = { .type = NLA_U64 },
1934};
1935
1936static int neightbl_set(struct sk_buff *skb, struct nlmsghdr *nlh)
1937{
1938 struct net *net = sock_net(skb->sk);
1939 struct neigh_table *tbl;
1940 struct ndtmsg *ndtmsg;
1941 struct nlattr *tb[NDTA_MAX+1];
1942 bool found = false;
1943 int err, tidx;
1944
1945 err = nlmsg_parse(nlh, sizeof(*ndtmsg), tb, NDTA_MAX,
1946 nl_neightbl_policy);
1947 if (err < 0)
1948 goto errout;
1949
1950 if (tb[NDTA_NAME] == NULL) {
1951 err = -EINVAL;
1952 goto errout;
1953 }
1954
1955 ndtmsg = nlmsg_data(nlh);
1956
1957 for (tidx = 0; tidx < NEIGH_NR_TABLES; tidx++) {
1958 tbl = neigh_tables[tidx];
1959 if (!tbl)
1960 continue;
1961 if (ndtmsg->ndtm_family && tbl->family != ndtmsg->ndtm_family)
1962 continue;
1963 if (nla_strcmp(tb[NDTA_NAME], tbl->id) == 0) {
1964 found = true;
1965 break;
1966 }
1967 }
1968
1969 if (!found)
1970 return -ENOENT;
1971
1972 /*
1973 * We acquire tbl->lock to be nice to the periodic timers and
1974 * make sure they always see a consistent set of values.
1975 */
1976 write_lock_bh(&tbl->lock);
1977
1978 if (tb[NDTA_PARMS]) {
1979 struct nlattr *tbp[NDTPA_MAX+1];
1980 struct neigh_parms *p;
1981 int i, ifindex = 0;
1982
1983 err = nla_parse_nested(tbp, NDTPA_MAX, tb[NDTA_PARMS],
1984 nl_ntbl_parm_policy);
1985 if (err < 0)
1986 goto errout_tbl_lock;
1987
1988 if (tbp[NDTPA_IFINDEX])
1989 ifindex = nla_get_u32(tbp[NDTPA_IFINDEX]);
1990
1991 p = lookup_neigh_parms(tbl, net, ifindex);
1992 if (p == NULL) {
1993 err = -ENOENT;
1994 goto errout_tbl_lock;
1995 }
1996
1997 for (i = 1; i <= NDTPA_MAX; i++) {
1998 if (tbp[i] == NULL)
1999 continue;
2000
2001 switch (i) {
2002 case NDTPA_QUEUE_LEN:
2003 NEIGH_VAR_SET(p, QUEUE_LEN_BYTES,
2004 nla_get_u32(tbp[i]) *
2005 SKB_TRUESIZE(ETH_FRAME_LEN));
2006 break;
2007 case NDTPA_QUEUE_LENBYTES:
2008 NEIGH_VAR_SET(p, QUEUE_LEN_BYTES,
2009 nla_get_u32(tbp[i]));
2010 break;
2011 case NDTPA_PROXY_QLEN:
2012 NEIGH_VAR_SET(p, PROXY_QLEN,
2013 nla_get_u32(tbp[i]));
2014 break;
2015 case NDTPA_APP_PROBES:
2016 NEIGH_VAR_SET(p, APP_PROBES,
2017 nla_get_u32(tbp[i]));
2018 break;
2019 case NDTPA_UCAST_PROBES:
2020 NEIGH_VAR_SET(p, UCAST_PROBES,
2021 nla_get_u32(tbp[i]));
2022 break;
2023 case NDTPA_MCAST_PROBES:
2024 NEIGH_VAR_SET(p, MCAST_PROBES,
2025 nla_get_u32(tbp[i]));
2026 break;
2027 case NDTPA_MCAST_REPROBES:
2028 NEIGH_VAR_SET(p, MCAST_REPROBES,
2029 nla_get_u32(tbp[i]));
2030 break;
2031 case NDTPA_BASE_REACHABLE_TIME:
2032 NEIGH_VAR_SET(p, BASE_REACHABLE_TIME,
2033 nla_get_msecs(tbp[i]));
2034 /* update reachable_time as well, otherwise, the change will
2035 * only be effective after the next time neigh_periodic_work
2036 * decides to recompute it (can be multiple minutes)
2037 */
2038 p->reachable_time =
2039 neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME));
2040 break;
2041 case NDTPA_GC_STALETIME:
2042 NEIGH_VAR_SET(p, GC_STALETIME,
2043 nla_get_msecs(tbp[i]));
2044 break;
2045 case NDTPA_DELAY_PROBE_TIME:
2046 NEIGH_VAR_SET(p, DELAY_PROBE_TIME,
2047 nla_get_msecs(tbp[i]));
2048 break;
2049 case NDTPA_RETRANS_TIME:
2050 NEIGH_VAR_SET(p, RETRANS_TIME,
2051 nla_get_msecs(tbp[i]));
2052 break;
2053 case NDTPA_ANYCAST_DELAY:
2054 NEIGH_VAR_SET(p, ANYCAST_DELAY,
2055 nla_get_msecs(tbp[i]));
2056 break;
2057 case NDTPA_PROXY_DELAY:
2058 NEIGH_VAR_SET(p, PROXY_DELAY,
2059 nla_get_msecs(tbp[i]));
2060 break;
2061 case NDTPA_LOCKTIME:
2062 NEIGH_VAR_SET(p, LOCKTIME,
2063 nla_get_msecs(tbp[i]));
2064 break;
2065 }
2066 }
2067 }
2068
2069 err = -ENOENT;
2070 if ((tb[NDTA_THRESH1] || tb[NDTA_THRESH2] ||
2071 tb[NDTA_THRESH3] || tb[NDTA_GC_INTERVAL]) &&
2072 !net_eq(net, &init_net))
2073 goto errout_tbl_lock;
2074
2075 if (tb[NDTA_THRESH1])
2076 tbl->gc_thresh1 = nla_get_u32(tb[NDTA_THRESH1]);
2077
2078 if (tb[NDTA_THRESH2])
2079 tbl->gc_thresh2 = nla_get_u32(tb[NDTA_THRESH2]);
2080
2081 if (tb[NDTA_THRESH3])
2082 tbl->gc_thresh3 = nla_get_u32(tb[NDTA_THRESH3]);
2083
2084 if (tb[NDTA_GC_INTERVAL])
2085 tbl->gc_interval = nla_get_msecs(tb[NDTA_GC_INTERVAL]);
2086
2087 err = 0;
2088
2089errout_tbl_lock:
2090 write_unlock_bh(&tbl->lock);
2091errout:
2092 return err;
2093}
2094
2095static int neightbl_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
2096{
2097 struct net *net = sock_net(skb->sk);
2098 int family, tidx, nidx = 0;
2099 int tbl_skip = cb->args[0];
2100 int neigh_skip = cb->args[1];
2101 struct neigh_table *tbl;
2102
2103 family = ((struct rtgenmsg *) nlmsg_data(cb->nlh))->rtgen_family;
2104
2105 for (tidx = 0; tidx < NEIGH_NR_TABLES; tidx++) {
2106 struct neigh_parms *p;
2107
2108 tbl = neigh_tables[tidx];
2109 if (!tbl)
2110 continue;
2111
2112 if (tidx < tbl_skip || (family && tbl->family != family))
2113 continue;
2114
2115 if (neightbl_fill_info(skb, tbl, NETLINK_CB(cb->skb).portid,
2116 cb->nlh->nlmsg_seq, RTM_NEWNEIGHTBL,
2117 NLM_F_MULTI) < 0)
2118 break;
2119
2120 nidx = 0;
2121 p = list_next_entry(&tbl->parms, list);
2122 list_for_each_entry_from(p, &tbl->parms_list, list) {
2123 if (!net_eq(neigh_parms_net(p), net))
2124 continue;
2125
2126 if (nidx < neigh_skip)
2127 goto next;
2128
2129 if (neightbl_fill_param_info(skb, tbl, p,
2130 NETLINK_CB(cb->skb).portid,
2131 cb->nlh->nlmsg_seq,
2132 RTM_NEWNEIGHTBL,
2133 NLM_F_MULTI) < 0)
2134 goto out;
2135 next:
2136 nidx++;
2137 }
2138
2139 neigh_skip = 0;
2140 }
2141out:
2142 cb->args[0] = tidx;
2143 cb->args[1] = nidx;
2144
2145 return skb->len;
2146}
2147
2148static int neigh_fill_info(struct sk_buff *skb, struct neighbour *neigh,
2149 u32 pid, u32 seq, int type, unsigned int flags)
2150{
2151 unsigned long now = jiffies;
2152 struct nda_cacheinfo ci;
2153 struct nlmsghdr *nlh;
2154 struct ndmsg *ndm;
2155
2156 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndm), flags);
2157 if (nlh == NULL)
2158 return -EMSGSIZE;
2159
2160 ndm = nlmsg_data(nlh);
2161 ndm->ndm_family = neigh->ops->family;
2162 ndm->ndm_pad1 = 0;
2163 ndm->ndm_pad2 = 0;
2164 ndm->ndm_flags = neigh->flags;
2165 ndm->ndm_type = neigh->type;
2166 ndm->ndm_ifindex = neigh->dev->ifindex;
2167
2168 if (nla_put(skb, NDA_DST, neigh->tbl->key_len, neigh->primary_key))
2169 goto nla_put_failure;
2170
2171 read_lock_bh(&neigh->lock);
2172 ndm->ndm_state = neigh->nud_state;
2173 if (neigh->nud_state & NUD_VALID) {
2174 char haddr[MAX_ADDR_LEN];
2175
2176 neigh_ha_snapshot(haddr, neigh, neigh->dev);
2177 if (nla_put(skb, NDA_LLADDR, neigh->dev->addr_len, haddr) < 0) {
2178 read_unlock_bh(&neigh->lock);
2179 goto nla_put_failure;
2180 }
2181 }
2182
2183 ci.ndm_used = jiffies_to_clock_t(now - neigh->used);
2184 ci.ndm_confirmed = jiffies_to_clock_t(now - neigh->confirmed);
2185 ci.ndm_updated = jiffies_to_clock_t(now - neigh->updated);
2186 ci.ndm_refcnt = atomic_read(&neigh->refcnt) - 1;
2187 read_unlock_bh(&neigh->lock);
2188
2189 if (nla_put_u32(skb, NDA_PROBES, atomic_read(&neigh->probes)) ||
2190 nla_put(skb, NDA_CACHEINFO, sizeof(ci), &ci))
2191 goto nla_put_failure;
2192
2193 nlmsg_end(skb, nlh);
2194 return 0;
2195
2196nla_put_failure:
2197 nlmsg_cancel(skb, nlh);
2198 return -EMSGSIZE;
2199}
2200
2201static int pneigh_fill_info(struct sk_buff *skb, struct pneigh_entry *pn,
2202 u32 pid, u32 seq, int type, unsigned int flags,
2203 struct neigh_table *tbl)
2204{
2205 struct nlmsghdr *nlh;
2206 struct ndmsg *ndm;
2207
2208 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndm), flags);
2209 if (nlh == NULL)
2210 return -EMSGSIZE;
2211
2212 ndm = nlmsg_data(nlh);
2213 ndm->ndm_family = tbl->family;
2214 ndm->ndm_pad1 = 0;
2215 ndm->ndm_pad2 = 0;
2216 ndm->ndm_flags = pn->flags | NTF_PROXY;
2217 ndm->ndm_type = RTN_UNICAST;
2218 ndm->ndm_ifindex = pn->dev ? pn->dev->ifindex : 0;
2219 ndm->ndm_state = NUD_NONE;
2220
2221 if (nla_put(skb, NDA_DST, tbl->key_len, pn->key))
2222 goto nla_put_failure;
2223
2224 nlmsg_end(skb, nlh);
2225 return 0;
2226
2227nla_put_failure:
2228 nlmsg_cancel(skb, nlh);
2229 return -EMSGSIZE;
2230}
2231
2232static void neigh_update_notify(struct neighbour *neigh)
2233{
2234 call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, neigh);
2235 __neigh_notify(neigh, RTM_NEWNEIGH, 0);
2236}
2237
2238static bool neigh_master_filtered(struct net_device *dev, int master_idx)
2239{
2240 struct net_device *master;
2241
2242 if (!master_idx)
2243 return false;
2244
2245 master = netdev_master_upper_dev_get(dev);
2246 if (!master || master->ifindex != master_idx)
2247 return true;
2248
2249 return false;
2250}
2251
2252static bool neigh_ifindex_filtered(struct net_device *dev, int filter_idx)
2253{
2254 if (filter_idx && dev->ifindex != filter_idx)
2255 return true;
2256
2257 return false;
2258}
2259
2260static int neigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb,
2261 struct netlink_callback *cb)
2262{
2263 struct net *net = sock_net(skb->sk);
2264 const struct nlmsghdr *nlh = cb->nlh;
2265 struct nlattr *tb[NDA_MAX + 1];
2266 struct neighbour *n;
2267 int rc, h, s_h = cb->args[1];
2268 int idx, s_idx = idx = cb->args[2];
2269 struct neigh_hash_table *nht;
2270 int filter_master_idx = 0, filter_idx = 0;
2271 unsigned int flags = NLM_F_MULTI;
2272 int err;
2273
2274 err = nlmsg_parse(nlh, sizeof(struct ndmsg), tb, NDA_MAX, NULL);
2275 if (!err) {
2276 if (tb[NDA_IFINDEX])
2277 filter_idx = nla_get_u32(tb[NDA_IFINDEX]);
2278
2279 if (tb[NDA_MASTER])
2280 filter_master_idx = nla_get_u32(tb[NDA_MASTER]);
2281
2282 if (filter_idx || filter_master_idx)
2283 flags |= NLM_F_DUMP_FILTERED;
2284 }
2285
2286 rcu_read_lock_bh();
2287 nht = rcu_dereference_bh(tbl->nht);
2288
2289 for (h = s_h; h < (1 << nht->hash_shift); h++) {
2290 if (h > s_h)
2291 s_idx = 0;
2292 for (n = rcu_dereference_bh(nht->hash_buckets[h]), idx = 0;
2293 n != NULL;
2294 n = rcu_dereference_bh(n->next)) {
2295 if (!net_eq(dev_net(n->dev), net))
2296 continue;
2297 if (neigh_ifindex_filtered(n->dev, filter_idx))
2298 continue;
2299 if (neigh_master_filtered(n->dev, filter_master_idx))
2300 continue;
2301 if (idx < s_idx)
2302 goto next;
2303 if (neigh_fill_info(skb, n, NETLINK_CB(cb->skb).portid,
2304 cb->nlh->nlmsg_seq,
2305 RTM_NEWNEIGH,
2306 flags) < 0) {
2307 rc = -1;
2308 goto out;
2309 }
2310next:
2311 idx++;
2312 }
2313 }
2314 rc = skb->len;
2315out:
2316 rcu_read_unlock_bh();
2317 cb->args[1] = h;
2318 cb->args[2] = idx;
2319 return rc;
2320}
2321
2322static int pneigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb,
2323 struct netlink_callback *cb)
2324{
2325 struct pneigh_entry *n;
2326 struct net *net = sock_net(skb->sk);
2327 int rc, h, s_h = cb->args[3];
2328 int idx, s_idx = idx = cb->args[4];
2329
2330 read_lock_bh(&tbl->lock);
2331
2332 for (h = s_h; h <= PNEIGH_HASHMASK; h++) {
2333 if (h > s_h)
2334 s_idx = 0;
2335 for (n = tbl->phash_buckets[h], idx = 0; n; n = n->next) {
2336 if (pneigh_net(n) != net)
2337 continue;
2338 if (idx < s_idx)
2339 goto next;
2340 if (pneigh_fill_info(skb, n, NETLINK_CB(cb->skb).portid,
2341 cb->nlh->nlmsg_seq,
2342 RTM_NEWNEIGH,
2343 NLM_F_MULTI, tbl) < 0) {
2344 read_unlock_bh(&tbl->lock);
2345 rc = -1;
2346 goto out;
2347 }
2348 next:
2349 idx++;
2350 }
2351 }
2352
2353 read_unlock_bh(&tbl->lock);
2354 rc = skb->len;
2355out:
2356 cb->args[3] = h;
2357 cb->args[4] = idx;
2358 return rc;
2359
2360}
2361
2362static int neigh_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
2363{
2364 struct neigh_table *tbl;
2365 int t, family, s_t;
2366 int proxy = 0;
2367 int err;
2368
2369 family = ((struct rtgenmsg *) nlmsg_data(cb->nlh))->rtgen_family;
2370
2371 /* check for full ndmsg structure presence, family member is
2372 * the same for both structures
2373 */
2374 if (nlmsg_len(cb->nlh) >= sizeof(struct ndmsg) &&
2375 ((struct ndmsg *) nlmsg_data(cb->nlh))->ndm_flags == NTF_PROXY)
2376 proxy = 1;
2377
2378 s_t = cb->args[0];
2379
2380 for (t = 0; t < NEIGH_NR_TABLES; t++) {
2381 tbl = neigh_tables[t];
2382
2383 if (!tbl)
2384 continue;
2385 if (t < s_t || (family && tbl->family != family))
2386 continue;
2387 if (t > s_t)
2388 memset(&cb->args[1], 0, sizeof(cb->args) -
2389 sizeof(cb->args[0]));
2390 if (proxy)
2391 err = pneigh_dump_table(tbl, skb, cb);
2392 else
2393 err = neigh_dump_table(tbl, skb, cb);
2394 if (err < 0)
2395 break;
2396 }
2397
2398 cb->args[0] = t;
2399 return skb->len;
2400}
2401
2402void neigh_for_each(struct neigh_table *tbl, void (*cb)(struct neighbour *, void *), void *cookie)
2403{
2404 int chain;
2405 struct neigh_hash_table *nht;
2406
2407 rcu_read_lock_bh();
2408 nht = rcu_dereference_bh(tbl->nht);
2409
2410 read_lock(&tbl->lock); /* avoid resizes */
2411 for (chain = 0; chain < (1 << nht->hash_shift); chain++) {
2412 struct neighbour *n;
2413
2414 for (n = rcu_dereference_bh(nht->hash_buckets[chain]);
2415 n != NULL;
2416 n = rcu_dereference_bh(n->next))
2417 cb(n, cookie);
2418 }
2419 read_unlock(&tbl->lock);
2420 rcu_read_unlock_bh();
2421}
2422EXPORT_SYMBOL(neigh_for_each);
2423
2424/* The tbl->lock must be held as a writer and BH disabled. */
2425void __neigh_for_each_release(struct neigh_table *tbl,
2426 int (*cb)(struct neighbour *))
2427{
2428 int chain;
2429 struct neigh_hash_table *nht;
2430
2431 nht = rcu_dereference_protected(tbl->nht,
2432 lockdep_is_held(&tbl->lock));
2433 for (chain = 0; chain < (1 << nht->hash_shift); chain++) {
2434 struct neighbour *n;
2435 struct neighbour __rcu **np;
2436
2437 np = &nht->hash_buckets[chain];
2438 while ((n = rcu_dereference_protected(*np,
2439 lockdep_is_held(&tbl->lock))) != NULL) {
2440 int release;
2441
2442 write_lock(&n->lock);
2443 release = cb(n);
2444 if (release) {
2445 rcu_assign_pointer(*np,
2446 rcu_dereference_protected(n->next,
2447 lockdep_is_held(&tbl->lock)));
2448 n->dead = 1;
2449 } else
2450 np = &n->next;
2451 write_unlock(&n->lock);
2452 if (release)
2453 neigh_cleanup_and_release(n);
2454 }
2455 }
2456}
2457EXPORT_SYMBOL(__neigh_for_each_release);
2458
2459int neigh_xmit(int index, struct net_device *dev,
2460 const void *addr, struct sk_buff *skb)
2461{
2462 int err = -EAFNOSUPPORT;
2463 if (likely(index < NEIGH_NR_TABLES)) {
2464 struct neigh_table *tbl;
2465 struct neighbour *neigh;
2466
2467 tbl = neigh_tables[index];
2468 if (!tbl)
2469 goto out;
2470 neigh = __neigh_lookup_noref(tbl, addr, dev);
2471 if (!neigh)
2472 neigh = __neigh_create(tbl, addr, dev, false);
2473 err = PTR_ERR(neigh);
2474 if (IS_ERR(neigh))
2475 goto out_kfree_skb;
2476 err = neigh->output(neigh, skb);
2477 }
2478 else if (index == NEIGH_LINK_TABLE) {
2479 err = dev_hard_header(skb, dev, ntohs(skb->protocol),
2480 addr, NULL, skb->len);
2481 if (err < 0)
2482 goto out_kfree_skb;
2483 err = dev_queue_xmit(skb);
2484 }
2485out:
2486 return err;
2487out_kfree_skb:
2488 kfree_skb(skb);
2489 goto out;
2490}
2491EXPORT_SYMBOL(neigh_xmit);
2492
2493#ifdef CONFIG_PROC_FS
2494
2495static struct neighbour *neigh_get_first(struct seq_file *seq)
2496{
2497 struct neigh_seq_state *state = seq->private;
2498 struct net *net = seq_file_net(seq);
2499 struct neigh_hash_table *nht = state->nht;
2500 struct neighbour *n = NULL;
2501 int bucket = state->bucket;
2502
2503 state->flags &= ~NEIGH_SEQ_IS_PNEIGH;
2504 for (bucket = 0; bucket < (1 << nht->hash_shift); bucket++) {
2505 n = rcu_dereference_bh(nht->hash_buckets[bucket]);
2506
2507 while (n) {
2508 if (!net_eq(dev_net(n->dev), net))
2509 goto next;
2510 if (state->neigh_sub_iter) {
2511 loff_t fakep = 0;
2512 void *v;
2513
2514 v = state->neigh_sub_iter(state, n, &fakep);
2515 if (!v)
2516 goto next;
2517 }
2518 if (!(state->flags & NEIGH_SEQ_SKIP_NOARP))
2519 break;
2520 if (n->nud_state & ~NUD_NOARP)
2521 break;
2522next:
2523 n = rcu_dereference_bh(n->next);
2524 }
2525
2526 if (n)
2527 break;
2528 }
2529 state->bucket = bucket;
2530
2531 return n;
2532}
2533
2534static struct neighbour *neigh_get_next(struct seq_file *seq,
2535 struct neighbour *n,
2536 loff_t *pos)
2537{
2538 struct neigh_seq_state *state = seq->private;
2539 struct net *net = seq_file_net(seq);
2540 struct neigh_hash_table *nht = state->nht;
2541
2542 if (state->neigh_sub_iter) {
2543 void *v = state->neigh_sub_iter(state, n, pos);
2544 if (v)
2545 return n;
2546 }
2547 n = rcu_dereference_bh(n->next);
2548
2549 while (1) {
2550 while (n) {
2551 if (!net_eq(dev_net(n->dev), net))
2552 goto next;
2553 if (state->neigh_sub_iter) {
2554 void *v = state->neigh_sub_iter(state, n, pos);
2555 if (v)
2556 return n;
2557 goto next;
2558 }
2559 if (!(state->flags & NEIGH_SEQ_SKIP_NOARP))
2560 break;
2561
2562 if (n->nud_state & ~NUD_NOARP)
2563 break;
2564next:
2565 n = rcu_dereference_bh(n->next);
2566 }
2567
2568 if (n)
2569 break;
2570
2571 if (++state->bucket >= (1 << nht->hash_shift))
2572 break;
2573
2574 n = rcu_dereference_bh(nht->hash_buckets[state->bucket]);
2575 }
2576
2577 if (n && pos)
2578 --(*pos);
2579 return n;
2580}
2581
2582static struct neighbour *neigh_get_idx(struct seq_file *seq, loff_t *pos)
2583{
2584 struct neighbour *n = neigh_get_first(seq);
2585
2586 if (n) {
2587 --(*pos);
2588 while (*pos) {
2589 n = neigh_get_next(seq, n, pos);
2590 if (!n)
2591 break;
2592 }
2593 }
2594 return *pos ? NULL : n;
2595}
2596
2597static struct pneigh_entry *pneigh_get_first(struct seq_file *seq)
2598{
2599 struct neigh_seq_state *state = seq->private;
2600 struct net *net = seq_file_net(seq);
2601 struct neigh_table *tbl = state->tbl;
2602 struct pneigh_entry *pn = NULL;
2603 int bucket = state->bucket;
2604
2605 state->flags |= NEIGH_SEQ_IS_PNEIGH;
2606 for (bucket = 0; bucket <= PNEIGH_HASHMASK; bucket++) {
2607 pn = tbl->phash_buckets[bucket];
2608 while (pn && !net_eq(pneigh_net(pn), net))
2609 pn = pn->next;
2610 if (pn)
2611 break;
2612 }
2613 state->bucket = bucket;
2614
2615 return pn;
2616}
2617
2618static struct pneigh_entry *pneigh_get_next(struct seq_file *seq,
2619 struct pneigh_entry *pn,
2620 loff_t *pos)
2621{
2622 struct neigh_seq_state *state = seq->private;
2623 struct net *net = seq_file_net(seq);
2624 struct neigh_table *tbl = state->tbl;
2625
2626 do {
2627 pn = pn->next;
2628 } while (pn && !net_eq(pneigh_net(pn), net));
2629
2630 while (!pn) {
2631 if (++state->bucket > PNEIGH_HASHMASK)
2632 break;
2633 pn = tbl->phash_buckets[state->bucket];
2634 while (pn && !net_eq(pneigh_net(pn), net))
2635 pn = pn->next;
2636 if (pn)
2637 break;
2638 }
2639
2640 if (pn && pos)
2641 --(*pos);
2642
2643 return pn;
2644}
2645
2646static struct pneigh_entry *pneigh_get_idx(struct seq_file *seq, loff_t *pos)
2647{
2648 struct pneigh_entry *pn = pneigh_get_first(seq);
2649
2650 if (pn) {
2651 --(*pos);
2652 while (*pos) {
2653 pn = pneigh_get_next(seq, pn, pos);
2654 if (!pn)
2655 break;
2656 }
2657 }
2658 return *pos ? NULL : pn;
2659}
2660
2661static void *neigh_get_idx_any(struct seq_file *seq, loff_t *pos)
2662{
2663 struct neigh_seq_state *state = seq->private;
2664 void *rc;
2665 loff_t idxpos = *pos;
2666
2667 rc = neigh_get_idx(seq, &idxpos);
2668 if (!rc && !(state->flags & NEIGH_SEQ_NEIGH_ONLY))
2669 rc = pneigh_get_idx(seq, &idxpos);
2670
2671 return rc;
2672}
2673
2674void *neigh_seq_start(struct seq_file *seq, loff_t *pos, struct neigh_table *tbl, unsigned int neigh_seq_flags)
2675 __acquires(rcu_bh)
2676{
2677 struct neigh_seq_state *state = seq->private;
2678
2679 state->tbl = tbl;
2680 state->bucket = 0;
2681 state->flags = (neigh_seq_flags & ~NEIGH_SEQ_IS_PNEIGH);
2682
2683 rcu_read_lock_bh();
2684 state->nht = rcu_dereference_bh(tbl->nht);
2685
2686 return *pos ? neigh_get_idx_any(seq, pos) : SEQ_START_TOKEN;
2687}
2688EXPORT_SYMBOL(neigh_seq_start);
2689
2690void *neigh_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2691{
2692 struct neigh_seq_state *state;
2693 void *rc;
2694
2695 if (v == SEQ_START_TOKEN) {
2696 rc = neigh_get_first(seq);
2697 goto out;
2698 }
2699
2700 state = seq->private;
2701 if (!(state->flags & NEIGH_SEQ_IS_PNEIGH)) {
2702 rc = neigh_get_next(seq, v, NULL);
2703 if (rc)
2704 goto out;
2705 if (!(state->flags & NEIGH_SEQ_NEIGH_ONLY))
2706 rc = pneigh_get_first(seq);
2707 } else {
2708 BUG_ON(state->flags & NEIGH_SEQ_NEIGH_ONLY);
2709 rc = pneigh_get_next(seq, v, NULL);
2710 }
2711out:
2712 ++(*pos);
2713 return rc;
2714}
2715EXPORT_SYMBOL(neigh_seq_next);
2716
2717void neigh_seq_stop(struct seq_file *seq, void *v)
2718 __releases(rcu_bh)
2719{
2720 rcu_read_unlock_bh();
2721}
2722EXPORT_SYMBOL(neigh_seq_stop);
2723
2724/* statistics via seq_file */
2725
2726static void *neigh_stat_seq_start(struct seq_file *seq, loff_t *pos)
2727{
2728 struct neigh_table *tbl = seq->private;
2729 int cpu;
2730
2731 if (*pos == 0)
2732 return SEQ_START_TOKEN;
2733
2734 for (cpu = *pos-1; cpu < nr_cpu_ids; ++cpu) {
2735 if (!cpu_possible(cpu))
2736 continue;
2737 *pos = cpu+1;
2738 return per_cpu_ptr(tbl->stats, cpu);
2739 }
2740 return NULL;
2741}
2742
2743static void *neigh_stat_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2744{
2745 struct neigh_table *tbl = seq->private;
2746 int cpu;
2747
2748 for (cpu = *pos; cpu < nr_cpu_ids; ++cpu) {
2749 if (!cpu_possible(cpu))
2750 continue;
2751 *pos = cpu+1;
2752 return per_cpu_ptr(tbl->stats, cpu);
2753 }
2754 return NULL;
2755}
2756
2757static void neigh_stat_seq_stop(struct seq_file *seq, void *v)
2758{
2759
2760}
2761
2762static int neigh_stat_seq_show(struct seq_file *seq, void *v)
2763{
2764 struct neigh_table *tbl = seq->private;
2765 struct neigh_statistics *st = v;
2766
2767 if (v == SEQ_START_TOKEN) {
2768 seq_printf(seq, "entries allocs destroys hash_grows lookups hits res_failed rcv_probes_mcast rcv_probes_ucast periodic_gc_runs forced_gc_runs unresolved_discards table_fulls\n");
2769 return 0;
2770 }
2771
2772 seq_printf(seq, "%08x %08lx %08lx %08lx %08lx %08lx %08lx "
2773 "%08lx %08lx %08lx %08lx %08lx %08lx\n",
2774 atomic_read(&tbl->entries),
2775
2776 st->allocs,
2777 st->destroys,
2778 st->hash_grows,
2779
2780 st->lookups,
2781 st->hits,
2782
2783 st->res_failed,
2784
2785 st->rcv_probes_mcast,
2786 st->rcv_probes_ucast,
2787
2788 st->periodic_gc_runs,
2789 st->forced_gc_runs,
2790 st->unres_discards,
2791 st->table_fulls
2792 );
2793
2794 return 0;
2795}
2796
2797static const struct seq_operations neigh_stat_seq_ops = {
2798 .start = neigh_stat_seq_start,
2799 .next = neigh_stat_seq_next,
2800 .stop = neigh_stat_seq_stop,
2801 .show = neigh_stat_seq_show,
2802};
2803
2804static int neigh_stat_seq_open(struct inode *inode, struct file *file)
2805{
2806 int ret = seq_open(file, &neigh_stat_seq_ops);
2807
2808 if (!ret) {
2809 struct seq_file *sf = file->private_data;
2810 sf->private = PDE_DATA(inode);
2811 }
2812 return ret;
2813};
2814
2815static const struct file_operations neigh_stat_seq_fops = {
2816 .owner = THIS_MODULE,
2817 .open = neigh_stat_seq_open,
2818 .read = seq_read,
2819 .llseek = seq_lseek,
2820 .release = seq_release,
2821};
2822
2823#endif /* CONFIG_PROC_FS */
2824
2825static inline size_t neigh_nlmsg_size(void)
2826{
2827 return NLMSG_ALIGN(sizeof(struct ndmsg))
2828 + nla_total_size(MAX_ADDR_LEN) /* NDA_DST */
2829 + nla_total_size(MAX_ADDR_LEN) /* NDA_LLADDR */
2830 + nla_total_size(sizeof(struct nda_cacheinfo))
2831 + nla_total_size(4); /* NDA_PROBES */
2832}
2833
2834static void __neigh_notify(struct neighbour *n, int type, int flags)
2835{
2836 struct net *net = dev_net(n->dev);
2837 struct sk_buff *skb;
2838 int err = -ENOBUFS;
2839
2840 skb = nlmsg_new(neigh_nlmsg_size(), GFP_ATOMIC);
2841 if (skb == NULL)
2842 goto errout;
2843
2844 err = neigh_fill_info(skb, n, 0, 0, type, flags);
2845 if (err < 0) {
2846 /* -EMSGSIZE implies BUG in neigh_nlmsg_size() */
2847 WARN_ON(err == -EMSGSIZE);
2848 kfree_skb(skb);
2849 goto errout;
2850 }
2851 rtnl_notify(skb, net, 0, RTNLGRP_NEIGH, NULL, GFP_ATOMIC);
2852 return;
2853errout:
2854 if (err < 0)
2855 rtnl_set_sk_err(net, RTNLGRP_NEIGH, err);
2856}
2857
2858void neigh_app_ns(struct neighbour *n)
2859{
2860 __neigh_notify(n, RTM_GETNEIGH, NLM_F_REQUEST);
2861}
2862EXPORT_SYMBOL(neigh_app_ns);
2863
2864#ifdef CONFIG_SYSCTL
2865static int zero;
2866static int int_max = INT_MAX;
2867static int unres_qlen_max = INT_MAX / SKB_TRUESIZE(ETH_FRAME_LEN);
2868
2869static int proc_unres_qlen(struct ctl_table *ctl, int write,
2870 void __user *buffer, size_t *lenp, loff_t *ppos)
2871{
2872 int size, ret;
2873 struct ctl_table tmp = *ctl;
2874
2875 tmp.extra1 = &zero;
2876 tmp.extra2 = &unres_qlen_max;
2877 tmp.data = &size;
2878
2879 size = *(int *)ctl->data / SKB_TRUESIZE(ETH_FRAME_LEN);
2880 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
2881
2882 if (write && !ret)
2883 *(int *)ctl->data = size * SKB_TRUESIZE(ETH_FRAME_LEN);
2884 return ret;
2885}
2886
2887static struct neigh_parms *neigh_get_dev_parms_rcu(struct net_device *dev,
2888 int family)
2889{
2890 switch (family) {
2891 case AF_INET:
2892 return __in_dev_arp_parms_get_rcu(dev);
2893 case AF_INET6:
2894 return __in6_dev_nd_parms_get_rcu(dev);
2895 }
2896 return NULL;
2897}
2898
2899static void neigh_copy_dflt_parms(struct net *net, struct neigh_parms *p,
2900 int index)
2901{
2902 struct net_device *dev;
2903 int family = neigh_parms_family(p);
2904
2905 rcu_read_lock();
2906 for_each_netdev_rcu(net, dev) {
2907 struct neigh_parms *dst_p =
2908 neigh_get_dev_parms_rcu(dev, family);
2909
2910 if (dst_p && !test_bit(index, dst_p->data_state))
2911 dst_p->data[index] = p->data[index];
2912 }
2913 rcu_read_unlock();
2914}
2915
2916static void neigh_proc_update(struct ctl_table *ctl, int write)
2917{
2918 struct net_device *dev = ctl->extra1;
2919 struct neigh_parms *p = ctl->extra2;
2920 struct net *net = neigh_parms_net(p);
2921 int index = (int *) ctl->data - p->data;
2922
2923 if (!write)
2924 return;
2925
2926 set_bit(index, p->data_state);
2927 if (!dev) /* NULL dev means this is default value */
2928 neigh_copy_dflt_parms(net, p, index);
2929}
2930
2931static int neigh_proc_dointvec_zero_intmax(struct ctl_table *ctl, int write,
2932 void __user *buffer,
2933 size_t *lenp, loff_t *ppos)
2934{
2935 struct ctl_table tmp = *ctl;
2936 int ret;
2937
2938 tmp.extra1 = &zero;
2939 tmp.extra2 = &int_max;
2940
2941 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
2942 neigh_proc_update(ctl, write);
2943 return ret;
2944}
2945
2946int neigh_proc_dointvec(struct ctl_table *ctl, int write,
2947 void __user *buffer, size_t *lenp, loff_t *ppos)
2948{
2949 int ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
2950
2951 neigh_proc_update(ctl, write);
2952 return ret;
2953}
2954EXPORT_SYMBOL(neigh_proc_dointvec);
2955
2956int neigh_proc_dointvec_jiffies(struct ctl_table *ctl, int write,
2957 void __user *buffer,
2958 size_t *lenp, loff_t *ppos)
2959{
2960 int ret = proc_dointvec_jiffies(ctl, write, buffer, lenp, ppos);
2961
2962 neigh_proc_update(ctl, write);
2963 return ret;
2964}
2965EXPORT_SYMBOL(neigh_proc_dointvec_jiffies);
2966
2967static int neigh_proc_dointvec_userhz_jiffies(struct ctl_table *ctl, int write,
2968 void __user *buffer,
2969 size_t *lenp, loff_t *ppos)
2970{
2971 int ret = proc_dointvec_userhz_jiffies(ctl, write, buffer, lenp, ppos);
2972
2973 neigh_proc_update(ctl, write);
2974 return ret;
2975}
2976
2977int neigh_proc_dointvec_ms_jiffies(struct ctl_table *ctl, int write,
2978 void __user *buffer,
2979 size_t *lenp, loff_t *ppos)
2980{
2981 int ret = proc_dointvec_ms_jiffies(ctl, write, buffer, lenp, ppos);
2982
2983 neigh_proc_update(ctl, write);
2984 return ret;
2985}
2986EXPORT_SYMBOL(neigh_proc_dointvec_ms_jiffies);
2987
2988static int neigh_proc_dointvec_unres_qlen(struct ctl_table *ctl, int write,
2989 void __user *buffer,
2990 size_t *lenp, loff_t *ppos)
2991{
2992 int ret = proc_unres_qlen(ctl, write, buffer, lenp, ppos);
2993
2994 neigh_proc_update(ctl, write);
2995 return ret;
2996}
2997
2998static int neigh_proc_base_reachable_time(struct ctl_table *ctl, int write,
2999 void __user *buffer,
3000 size_t *lenp, loff_t *ppos)
3001{
3002 struct neigh_parms *p = ctl->extra2;
3003 int ret;
3004
3005 if (strcmp(ctl->procname, "base_reachable_time") == 0)
3006 ret = neigh_proc_dointvec_jiffies(ctl, write, buffer, lenp, ppos);
3007 else if (strcmp(ctl->procname, "base_reachable_time_ms") == 0)
3008 ret = neigh_proc_dointvec_ms_jiffies(ctl, write, buffer, lenp, ppos);
3009 else
3010 ret = -1;
3011
3012 if (write && ret == 0) {
3013 /* update reachable_time as well, otherwise, the change will
3014 * only be effective after the next time neigh_periodic_work
3015 * decides to recompute it
3016 */
3017 p->reachable_time =
3018 neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME));
3019 }
3020 return ret;
3021}
3022
3023#define NEIGH_PARMS_DATA_OFFSET(index) \
3024 (&((struct neigh_parms *) 0)->data[index])
3025
3026#define NEIGH_SYSCTL_ENTRY(attr, data_attr, name, mval, proc) \
3027 [NEIGH_VAR_ ## attr] = { \
3028 .procname = name, \
3029 .data = NEIGH_PARMS_DATA_OFFSET(NEIGH_VAR_ ## data_attr), \
3030 .maxlen = sizeof(int), \
3031 .mode = mval, \
3032 .proc_handler = proc, \
3033 }
3034
3035#define NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(attr, name) \
3036 NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_zero_intmax)
3037
3038#define NEIGH_SYSCTL_JIFFIES_ENTRY(attr, name) \
3039 NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_jiffies)
3040
3041#define NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(attr, name) \
3042 NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_userhz_jiffies)
3043
3044#define NEIGH_SYSCTL_MS_JIFFIES_ENTRY(attr, name) \
3045 NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_ms_jiffies)
3046
3047#define NEIGH_SYSCTL_MS_JIFFIES_REUSED_ENTRY(attr, data_attr, name) \
3048 NEIGH_SYSCTL_ENTRY(attr, data_attr, name, 0644, neigh_proc_dointvec_ms_jiffies)
3049
3050#define NEIGH_SYSCTL_UNRES_QLEN_REUSED_ENTRY(attr, data_attr, name) \
3051 NEIGH_SYSCTL_ENTRY(attr, data_attr, name, 0644, neigh_proc_dointvec_unres_qlen)
3052
3053static struct neigh_sysctl_table {
3054 struct ctl_table_header *sysctl_header;
3055 struct ctl_table neigh_vars[NEIGH_VAR_MAX + 1];
3056} neigh_sysctl_template __read_mostly = {
3057 .neigh_vars = {
3058 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(MCAST_PROBES, "mcast_solicit"),
3059 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(UCAST_PROBES, "ucast_solicit"),
3060 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(APP_PROBES, "app_solicit"),
3061 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(MCAST_REPROBES, "mcast_resolicit"),
3062 NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(RETRANS_TIME, "retrans_time"),
3063 NEIGH_SYSCTL_JIFFIES_ENTRY(BASE_REACHABLE_TIME, "base_reachable_time"),
3064 NEIGH_SYSCTL_JIFFIES_ENTRY(DELAY_PROBE_TIME, "delay_first_probe_time"),
3065 NEIGH_SYSCTL_JIFFIES_ENTRY(GC_STALETIME, "gc_stale_time"),
3066 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(QUEUE_LEN_BYTES, "unres_qlen_bytes"),
3067 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(PROXY_QLEN, "proxy_qlen"),
3068 NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(ANYCAST_DELAY, "anycast_delay"),
3069 NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(PROXY_DELAY, "proxy_delay"),
3070 NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(LOCKTIME, "locktime"),
3071 NEIGH_SYSCTL_UNRES_QLEN_REUSED_ENTRY(QUEUE_LEN, QUEUE_LEN_BYTES, "unres_qlen"),
3072 NEIGH_SYSCTL_MS_JIFFIES_REUSED_ENTRY(RETRANS_TIME_MS, RETRANS_TIME, "retrans_time_ms"),
3073 NEIGH_SYSCTL_MS_JIFFIES_REUSED_ENTRY(BASE_REACHABLE_TIME_MS, BASE_REACHABLE_TIME, "base_reachable_time_ms"),
3074 [NEIGH_VAR_GC_INTERVAL] = {
3075 .procname = "gc_interval",
3076 .maxlen = sizeof(int),
3077 .mode = 0644,
3078 .proc_handler = proc_dointvec_jiffies,
3079 },
3080 [NEIGH_VAR_GC_THRESH1] = {
3081 .procname = "gc_thresh1",
3082 .maxlen = sizeof(int),
3083 .mode = 0644,
3084 .extra1 = &zero,
3085 .extra2 = &int_max,
3086 .proc_handler = proc_dointvec_minmax,
3087 },
3088 [NEIGH_VAR_GC_THRESH2] = {
3089 .procname = "gc_thresh2",
3090 .maxlen = sizeof(int),
3091 .mode = 0644,
3092 .extra1 = &zero,
3093 .extra2 = &int_max,
3094 .proc_handler = proc_dointvec_minmax,
3095 },
3096 [NEIGH_VAR_GC_THRESH3] = {
3097 .procname = "gc_thresh3",
3098 .maxlen = sizeof(int),
3099 .mode = 0644,
3100 .extra1 = &zero,
3101 .extra2 = &int_max,
3102 .proc_handler = proc_dointvec_minmax,
3103 },
3104 {},
3105 },
3106};
3107
3108int neigh_sysctl_register(struct net_device *dev, struct neigh_parms *p,
3109 proc_handler *handler)
3110{
3111 int i;
3112 struct neigh_sysctl_table *t;
3113 const char *dev_name_source;
3114 char neigh_path[ sizeof("net//neigh/") + IFNAMSIZ + IFNAMSIZ ];
3115 char *p_name;
3116
3117 t = kmemdup(&neigh_sysctl_template, sizeof(*t), GFP_KERNEL);
3118 if (!t)
3119 goto err;
3120
3121 for (i = 0; i < NEIGH_VAR_GC_INTERVAL; i++) {
3122 t->neigh_vars[i].data += (long) p;
3123 t->neigh_vars[i].extra1 = dev;
3124 t->neigh_vars[i].extra2 = p;
3125 }
3126
3127 if (dev) {
3128 dev_name_source = dev->name;
3129 /* Terminate the table early */
3130 memset(&t->neigh_vars[NEIGH_VAR_GC_INTERVAL], 0,
3131 sizeof(t->neigh_vars[NEIGH_VAR_GC_INTERVAL]));
3132 } else {
3133 struct neigh_table *tbl = p->tbl;
3134 dev_name_source = "default";
3135 t->neigh_vars[NEIGH_VAR_GC_INTERVAL].data = &tbl->gc_interval;
3136 t->neigh_vars[NEIGH_VAR_GC_THRESH1].data = &tbl->gc_thresh1;
3137 t->neigh_vars[NEIGH_VAR_GC_THRESH2].data = &tbl->gc_thresh2;
3138 t->neigh_vars[NEIGH_VAR_GC_THRESH3].data = &tbl->gc_thresh3;
3139 }
3140
3141 if (handler) {
3142 /* RetransTime */
3143 t->neigh_vars[NEIGH_VAR_RETRANS_TIME].proc_handler = handler;
3144 /* ReachableTime */
3145 t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME].proc_handler = handler;
3146 /* RetransTime (in milliseconds)*/
3147 t->neigh_vars[NEIGH_VAR_RETRANS_TIME_MS].proc_handler = handler;
3148 /* ReachableTime (in milliseconds) */
3149 t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME_MS].proc_handler = handler;
3150 } else {
3151 /* Those handlers will update p->reachable_time after
3152 * base_reachable_time(_ms) is set to ensure the new timer starts being
3153 * applied after the next neighbour update instead of waiting for
3154 * neigh_periodic_work to update its value (can be multiple minutes)
3155 * So any handler that replaces them should do this as well
3156 */
3157 /* ReachableTime */
3158 t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME].proc_handler =
3159 neigh_proc_base_reachable_time;
3160 /* ReachableTime (in milliseconds) */
3161 t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME_MS].proc_handler =
3162 neigh_proc_base_reachable_time;
3163 }
3164
3165 /* Don't export sysctls to unprivileged users */
3166 if (neigh_parms_net(p)->user_ns != &init_user_ns)
3167 t->neigh_vars[0].procname = NULL;
3168
3169 switch (neigh_parms_family(p)) {
3170 case AF_INET:
3171 p_name = "ipv4";
3172 break;
3173 case AF_INET6:
3174 p_name = "ipv6";
3175 break;
3176 default:
3177 BUG();
3178 }
3179
3180 snprintf(neigh_path, sizeof(neigh_path), "net/%s/neigh/%s",
3181 p_name, dev_name_source);
3182 t->sysctl_header =
3183 register_net_sysctl(neigh_parms_net(p), neigh_path, t->neigh_vars);
3184 if (!t->sysctl_header)
3185 goto free;
3186
3187 p->sysctl_table = t;
3188 return 0;
3189
3190free:
3191 kfree(t);
3192err:
3193 return -ENOBUFS;
3194}
3195EXPORT_SYMBOL(neigh_sysctl_register);
3196
3197void neigh_sysctl_unregister(struct neigh_parms *p)
3198{
3199 if (p->sysctl_table) {
3200 struct neigh_sysctl_table *t = p->sysctl_table;
3201 p->sysctl_table = NULL;
3202 unregister_net_sysctl_table(t->sysctl_header);
3203 kfree(t);
3204 }
3205}
3206EXPORT_SYMBOL(neigh_sysctl_unregister);
3207
3208#endif /* CONFIG_SYSCTL */
3209
3210static int __init neigh_init(void)
3211{
3212 rtnl_register(PF_UNSPEC, RTM_NEWNEIGH, neigh_add, NULL, NULL);
3213 rtnl_register(PF_UNSPEC, RTM_DELNEIGH, neigh_delete, NULL, NULL);
3214 rtnl_register(PF_UNSPEC, RTM_GETNEIGH, NULL, neigh_dump_info, NULL);
3215
3216 rtnl_register(PF_UNSPEC, RTM_GETNEIGHTBL, NULL, neightbl_dump_info,
3217 NULL);
3218 rtnl_register(PF_UNSPEC, RTM_SETNEIGHTBL, neightbl_set, NULL, NULL);
3219
3220 return 0;
3221}
3222
3223subsys_initcall(neigh_init);
3224
1/*
2 * Generic address resolution entity
3 *
4 * Authors:
5 * Pedro Roque <roque@di.fc.ul.pt>
6 * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License
10 * as published by the Free Software Foundation; either version
11 * 2 of the License, or (at your option) any later version.
12 *
13 * Fixes:
14 * Vitaly E. Lavrov releasing NULL neighbor in neigh_add.
15 * Harald Welte Add neighbour cache statistics like rtstat
16 */
17
18#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
19
20#include <linux/slab.h>
21#include <linux/types.h>
22#include <linux/kernel.h>
23#include <linux/module.h>
24#include <linux/socket.h>
25#include <linux/netdevice.h>
26#include <linux/proc_fs.h>
27#ifdef CONFIG_SYSCTL
28#include <linux/sysctl.h>
29#endif
30#include <linux/times.h>
31#include <net/net_namespace.h>
32#include <net/neighbour.h>
33#include <net/dst.h>
34#include <net/sock.h>
35#include <net/netevent.h>
36#include <net/netlink.h>
37#include <linux/rtnetlink.h>
38#include <linux/random.h>
39#include <linux/string.h>
40#include <linux/log2.h>
41#include <linux/inetdevice.h>
42#include <net/addrconf.h>
43
44#define DEBUG
45#define NEIGH_DEBUG 1
46#define neigh_dbg(level, fmt, ...) \
47do { \
48 if (level <= NEIGH_DEBUG) \
49 pr_debug(fmt, ##__VA_ARGS__); \
50} while (0)
51
52#define PNEIGH_HASHMASK 0xF
53
54static void neigh_timer_handler(unsigned long arg);
55static void __neigh_notify(struct neighbour *n, int type, int flags);
56static void neigh_update_notify(struct neighbour *neigh);
57static int pneigh_ifdown(struct neigh_table *tbl, struct net_device *dev);
58
59#ifdef CONFIG_PROC_FS
60static const struct file_operations neigh_stat_seq_fops;
61#endif
62
63/*
64 Neighbour hash table buckets are protected with rwlock tbl->lock.
65
66 - All the scans/updates to hash buckets MUST be made under this lock.
67 - NOTHING clever should be made under this lock: no callbacks
68 to protocol backends, no attempts to send something to network.
69 It will result in deadlocks, if backend/driver wants to use neighbour
70 cache.
71 - If the entry requires some non-trivial actions, increase
72 its reference count and release table lock.
73
74 Neighbour entries are protected:
75 - with reference count.
76 - with rwlock neigh->lock
77
78 Reference count prevents destruction.
79
80 neigh->lock mainly serializes ll address data and its validity state.
81 However, the same lock is used to protect another entry fields:
82 - timer
83 - resolution queue
84
85 Again, nothing clever shall be made under neigh->lock,
86 the most complicated procedure, which we allow is dev->hard_header.
87 It is supposed, that dev->hard_header is simplistic and does
88 not make callbacks to neighbour tables.
89 */
90
91static int neigh_blackhole(struct neighbour *neigh, struct sk_buff *skb)
92{
93 kfree_skb(skb);
94 return -ENETDOWN;
95}
96
97static void neigh_cleanup_and_release(struct neighbour *neigh)
98{
99 if (neigh->parms->neigh_cleanup)
100 neigh->parms->neigh_cleanup(neigh);
101
102 __neigh_notify(neigh, RTM_DELNEIGH, 0);
103 call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, neigh);
104 neigh_release(neigh);
105}
106
107/*
108 * It is random distribution in the interval (1/2)*base...(3/2)*base.
109 * It corresponds to default IPv6 settings and is not overridable,
110 * because it is really reasonable choice.
111 */
112
113unsigned long neigh_rand_reach_time(unsigned long base)
114{
115 return base ? (prandom_u32() % base) + (base >> 1) : 0;
116}
117EXPORT_SYMBOL(neigh_rand_reach_time);
118
119
120static int neigh_forced_gc(struct neigh_table *tbl)
121{
122 int shrunk = 0;
123 int i;
124 struct neigh_hash_table *nht;
125
126 NEIGH_CACHE_STAT_INC(tbl, forced_gc_runs);
127
128 write_lock_bh(&tbl->lock);
129 nht = rcu_dereference_protected(tbl->nht,
130 lockdep_is_held(&tbl->lock));
131 for (i = 0; i < (1 << nht->hash_shift); i++) {
132 struct neighbour *n;
133 struct neighbour __rcu **np;
134
135 np = &nht->hash_buckets[i];
136 while ((n = rcu_dereference_protected(*np,
137 lockdep_is_held(&tbl->lock))) != NULL) {
138 /* Neighbour record may be discarded if:
139 * - nobody refers to it.
140 * - it is not permanent
141 */
142 write_lock(&n->lock);
143 if (atomic_read(&n->refcnt) == 1 &&
144 !(n->nud_state & NUD_PERMANENT)) {
145 rcu_assign_pointer(*np,
146 rcu_dereference_protected(n->next,
147 lockdep_is_held(&tbl->lock)));
148 n->dead = 1;
149 shrunk = 1;
150 write_unlock(&n->lock);
151 neigh_cleanup_and_release(n);
152 continue;
153 }
154 write_unlock(&n->lock);
155 np = &n->next;
156 }
157 }
158
159 tbl->last_flush = jiffies;
160
161 write_unlock_bh(&tbl->lock);
162
163 return shrunk;
164}
165
166static void neigh_add_timer(struct neighbour *n, unsigned long when)
167{
168 neigh_hold(n);
169 if (unlikely(mod_timer(&n->timer, when))) {
170 printk("NEIGH: BUG, double timer add, state is %x\n",
171 n->nud_state);
172 dump_stack();
173 }
174}
175
176static int neigh_del_timer(struct neighbour *n)
177{
178 if ((n->nud_state & NUD_IN_TIMER) &&
179 del_timer(&n->timer)) {
180 neigh_release(n);
181 return 1;
182 }
183 return 0;
184}
185
186static void pneigh_queue_purge(struct sk_buff_head *list)
187{
188 struct sk_buff *skb;
189
190 while ((skb = skb_dequeue(list)) != NULL) {
191 dev_put(skb->dev);
192 kfree_skb(skb);
193 }
194}
195
196static void neigh_flush_dev(struct neigh_table *tbl, struct net_device *dev)
197{
198 int i;
199 struct neigh_hash_table *nht;
200
201 nht = rcu_dereference_protected(tbl->nht,
202 lockdep_is_held(&tbl->lock));
203
204 for (i = 0; i < (1 << nht->hash_shift); i++) {
205 struct neighbour *n;
206 struct neighbour __rcu **np = &nht->hash_buckets[i];
207
208 while ((n = rcu_dereference_protected(*np,
209 lockdep_is_held(&tbl->lock))) != NULL) {
210 if (dev && n->dev != dev) {
211 np = &n->next;
212 continue;
213 }
214 rcu_assign_pointer(*np,
215 rcu_dereference_protected(n->next,
216 lockdep_is_held(&tbl->lock)));
217 write_lock(&n->lock);
218 neigh_del_timer(n);
219 n->dead = 1;
220
221 if (atomic_read(&n->refcnt) != 1) {
222 /* The most unpleasant situation.
223 We must destroy neighbour entry,
224 but someone still uses it.
225
226 The destroy will be delayed until
227 the last user releases us, but
228 we must kill timers etc. and move
229 it to safe state.
230 */
231 __skb_queue_purge(&n->arp_queue);
232 n->arp_queue_len_bytes = 0;
233 n->output = neigh_blackhole;
234 if (n->nud_state & NUD_VALID)
235 n->nud_state = NUD_NOARP;
236 else
237 n->nud_state = NUD_NONE;
238 neigh_dbg(2, "neigh %p is stray\n", n);
239 }
240 write_unlock(&n->lock);
241 neigh_cleanup_and_release(n);
242 }
243 }
244}
245
246void neigh_changeaddr(struct neigh_table *tbl, struct net_device *dev)
247{
248 write_lock_bh(&tbl->lock);
249 neigh_flush_dev(tbl, dev);
250 write_unlock_bh(&tbl->lock);
251}
252EXPORT_SYMBOL(neigh_changeaddr);
253
254int neigh_ifdown(struct neigh_table *tbl, struct net_device *dev)
255{
256 write_lock_bh(&tbl->lock);
257 neigh_flush_dev(tbl, dev);
258 pneigh_ifdown(tbl, dev);
259 write_unlock_bh(&tbl->lock);
260
261 del_timer_sync(&tbl->proxy_timer);
262 pneigh_queue_purge(&tbl->proxy_queue);
263 return 0;
264}
265EXPORT_SYMBOL(neigh_ifdown);
266
267static struct neighbour *neigh_alloc(struct neigh_table *tbl, struct net_device *dev)
268{
269 struct neighbour *n = NULL;
270 unsigned long now = jiffies;
271 int entries;
272
273 entries = atomic_inc_return(&tbl->entries) - 1;
274 if (entries >= tbl->gc_thresh3 ||
275 (entries >= tbl->gc_thresh2 &&
276 time_after(now, tbl->last_flush + 5 * HZ))) {
277 if (!neigh_forced_gc(tbl) &&
278 entries >= tbl->gc_thresh3) {
279 net_info_ratelimited("%s: neighbor table overflow!\n",
280 tbl->id);
281 NEIGH_CACHE_STAT_INC(tbl, table_fulls);
282 goto out_entries;
283 }
284 }
285
286 n = kzalloc(tbl->entry_size + dev->neigh_priv_len, GFP_ATOMIC);
287 if (!n)
288 goto out_entries;
289
290 __skb_queue_head_init(&n->arp_queue);
291 rwlock_init(&n->lock);
292 seqlock_init(&n->ha_lock);
293 n->updated = n->used = now;
294 n->nud_state = NUD_NONE;
295 n->output = neigh_blackhole;
296 seqlock_init(&n->hh.hh_lock);
297 n->parms = neigh_parms_clone(&tbl->parms);
298 setup_timer(&n->timer, neigh_timer_handler, (unsigned long)n);
299
300 NEIGH_CACHE_STAT_INC(tbl, allocs);
301 n->tbl = tbl;
302 atomic_set(&n->refcnt, 1);
303 n->dead = 1;
304out:
305 return n;
306
307out_entries:
308 atomic_dec(&tbl->entries);
309 goto out;
310}
311
312static void neigh_get_hash_rnd(u32 *x)
313{
314 get_random_bytes(x, sizeof(*x));
315 *x |= 1;
316}
317
318static struct neigh_hash_table *neigh_hash_alloc(unsigned int shift)
319{
320 size_t size = (1 << shift) * sizeof(struct neighbour *);
321 struct neigh_hash_table *ret;
322 struct neighbour __rcu **buckets;
323 int i;
324
325 ret = kmalloc(sizeof(*ret), GFP_ATOMIC);
326 if (!ret)
327 return NULL;
328 if (size <= PAGE_SIZE)
329 buckets = kzalloc(size, GFP_ATOMIC);
330 else
331 buckets = (struct neighbour __rcu **)
332 __get_free_pages(GFP_ATOMIC | __GFP_ZERO,
333 get_order(size));
334 if (!buckets) {
335 kfree(ret);
336 return NULL;
337 }
338 ret->hash_buckets = buckets;
339 ret->hash_shift = shift;
340 for (i = 0; i < NEIGH_NUM_HASH_RND; i++)
341 neigh_get_hash_rnd(&ret->hash_rnd[i]);
342 return ret;
343}
344
345static void neigh_hash_free_rcu(struct rcu_head *head)
346{
347 struct neigh_hash_table *nht = container_of(head,
348 struct neigh_hash_table,
349 rcu);
350 size_t size = (1 << nht->hash_shift) * sizeof(struct neighbour *);
351 struct neighbour __rcu **buckets = nht->hash_buckets;
352
353 if (size <= PAGE_SIZE)
354 kfree(buckets);
355 else
356 free_pages((unsigned long)buckets, get_order(size));
357 kfree(nht);
358}
359
360static struct neigh_hash_table *neigh_hash_grow(struct neigh_table *tbl,
361 unsigned long new_shift)
362{
363 unsigned int i, hash;
364 struct neigh_hash_table *new_nht, *old_nht;
365
366 NEIGH_CACHE_STAT_INC(tbl, hash_grows);
367
368 old_nht = rcu_dereference_protected(tbl->nht,
369 lockdep_is_held(&tbl->lock));
370 new_nht = neigh_hash_alloc(new_shift);
371 if (!new_nht)
372 return old_nht;
373
374 for (i = 0; i < (1 << old_nht->hash_shift); i++) {
375 struct neighbour *n, *next;
376
377 for (n = rcu_dereference_protected(old_nht->hash_buckets[i],
378 lockdep_is_held(&tbl->lock));
379 n != NULL;
380 n = next) {
381 hash = tbl->hash(n->primary_key, n->dev,
382 new_nht->hash_rnd);
383
384 hash >>= (32 - new_nht->hash_shift);
385 next = rcu_dereference_protected(n->next,
386 lockdep_is_held(&tbl->lock));
387
388 rcu_assign_pointer(n->next,
389 rcu_dereference_protected(
390 new_nht->hash_buckets[hash],
391 lockdep_is_held(&tbl->lock)));
392 rcu_assign_pointer(new_nht->hash_buckets[hash], n);
393 }
394 }
395
396 rcu_assign_pointer(tbl->nht, new_nht);
397 call_rcu(&old_nht->rcu, neigh_hash_free_rcu);
398 return new_nht;
399}
400
401struct neighbour *neigh_lookup(struct neigh_table *tbl, const void *pkey,
402 struct net_device *dev)
403{
404 struct neighbour *n;
405
406 NEIGH_CACHE_STAT_INC(tbl, lookups);
407
408 rcu_read_lock_bh();
409 n = __neigh_lookup_noref(tbl, pkey, dev);
410 if (n) {
411 if (!atomic_inc_not_zero(&n->refcnt))
412 n = NULL;
413 NEIGH_CACHE_STAT_INC(tbl, hits);
414 }
415
416 rcu_read_unlock_bh();
417 return n;
418}
419EXPORT_SYMBOL(neigh_lookup);
420
421struct neighbour *neigh_lookup_nodev(struct neigh_table *tbl, struct net *net,
422 const void *pkey)
423{
424 struct neighbour *n;
425 int key_len = tbl->key_len;
426 u32 hash_val;
427 struct neigh_hash_table *nht;
428
429 NEIGH_CACHE_STAT_INC(tbl, lookups);
430
431 rcu_read_lock_bh();
432 nht = rcu_dereference_bh(tbl->nht);
433 hash_val = tbl->hash(pkey, NULL, nht->hash_rnd) >> (32 - nht->hash_shift);
434
435 for (n = rcu_dereference_bh(nht->hash_buckets[hash_val]);
436 n != NULL;
437 n = rcu_dereference_bh(n->next)) {
438 if (!memcmp(n->primary_key, pkey, key_len) &&
439 net_eq(dev_net(n->dev), net)) {
440 if (!atomic_inc_not_zero(&n->refcnt))
441 n = NULL;
442 NEIGH_CACHE_STAT_INC(tbl, hits);
443 break;
444 }
445 }
446
447 rcu_read_unlock_bh();
448 return n;
449}
450EXPORT_SYMBOL(neigh_lookup_nodev);
451
452struct neighbour *__neigh_create(struct neigh_table *tbl, const void *pkey,
453 struct net_device *dev, bool want_ref)
454{
455 u32 hash_val;
456 int key_len = tbl->key_len;
457 int error;
458 struct neighbour *n1, *rc, *n = neigh_alloc(tbl, dev);
459 struct neigh_hash_table *nht;
460
461 if (!n) {
462 rc = ERR_PTR(-ENOBUFS);
463 goto out;
464 }
465
466 memcpy(n->primary_key, pkey, key_len);
467 n->dev = dev;
468 dev_hold(dev);
469
470 /* Protocol specific setup. */
471 if (tbl->constructor && (error = tbl->constructor(n)) < 0) {
472 rc = ERR_PTR(error);
473 goto out_neigh_release;
474 }
475
476 if (dev->netdev_ops->ndo_neigh_construct) {
477 error = dev->netdev_ops->ndo_neigh_construct(dev, n);
478 if (error < 0) {
479 rc = ERR_PTR(error);
480 goto out_neigh_release;
481 }
482 }
483
484 /* Device specific setup. */
485 if (n->parms->neigh_setup &&
486 (error = n->parms->neigh_setup(n)) < 0) {
487 rc = ERR_PTR(error);
488 goto out_neigh_release;
489 }
490
491 n->confirmed = jiffies - (NEIGH_VAR(n->parms, BASE_REACHABLE_TIME) << 1);
492
493 write_lock_bh(&tbl->lock);
494 nht = rcu_dereference_protected(tbl->nht,
495 lockdep_is_held(&tbl->lock));
496
497 if (atomic_read(&tbl->entries) > (1 << nht->hash_shift))
498 nht = neigh_hash_grow(tbl, nht->hash_shift + 1);
499
500 hash_val = tbl->hash(pkey, dev, nht->hash_rnd) >> (32 - nht->hash_shift);
501
502 if (n->parms->dead) {
503 rc = ERR_PTR(-EINVAL);
504 goto out_tbl_unlock;
505 }
506
507 for (n1 = rcu_dereference_protected(nht->hash_buckets[hash_val],
508 lockdep_is_held(&tbl->lock));
509 n1 != NULL;
510 n1 = rcu_dereference_protected(n1->next,
511 lockdep_is_held(&tbl->lock))) {
512 if (dev == n1->dev && !memcmp(n1->primary_key, pkey, key_len)) {
513 if (want_ref)
514 neigh_hold(n1);
515 rc = n1;
516 goto out_tbl_unlock;
517 }
518 }
519
520 n->dead = 0;
521 if (want_ref)
522 neigh_hold(n);
523 rcu_assign_pointer(n->next,
524 rcu_dereference_protected(nht->hash_buckets[hash_val],
525 lockdep_is_held(&tbl->lock)));
526 rcu_assign_pointer(nht->hash_buckets[hash_val], n);
527 write_unlock_bh(&tbl->lock);
528 neigh_dbg(2, "neigh %p is created\n", n);
529 rc = n;
530out:
531 return rc;
532out_tbl_unlock:
533 write_unlock_bh(&tbl->lock);
534out_neigh_release:
535 neigh_release(n);
536 goto out;
537}
538EXPORT_SYMBOL(__neigh_create);
539
540static u32 pneigh_hash(const void *pkey, int key_len)
541{
542 u32 hash_val = *(u32 *)(pkey + key_len - 4);
543 hash_val ^= (hash_val >> 16);
544 hash_val ^= hash_val >> 8;
545 hash_val ^= hash_val >> 4;
546 hash_val &= PNEIGH_HASHMASK;
547 return hash_val;
548}
549
550static struct pneigh_entry *__pneigh_lookup_1(struct pneigh_entry *n,
551 struct net *net,
552 const void *pkey,
553 int key_len,
554 struct net_device *dev)
555{
556 while (n) {
557 if (!memcmp(n->key, pkey, key_len) &&
558 net_eq(pneigh_net(n), net) &&
559 (n->dev == dev || !n->dev))
560 return n;
561 n = n->next;
562 }
563 return NULL;
564}
565
566struct pneigh_entry *__pneigh_lookup(struct neigh_table *tbl,
567 struct net *net, const void *pkey, struct net_device *dev)
568{
569 int key_len = tbl->key_len;
570 u32 hash_val = pneigh_hash(pkey, key_len);
571
572 return __pneigh_lookup_1(tbl->phash_buckets[hash_val],
573 net, pkey, key_len, dev);
574}
575EXPORT_SYMBOL_GPL(__pneigh_lookup);
576
577struct pneigh_entry * pneigh_lookup(struct neigh_table *tbl,
578 struct net *net, const void *pkey,
579 struct net_device *dev, int creat)
580{
581 struct pneigh_entry *n;
582 int key_len = tbl->key_len;
583 u32 hash_val = pneigh_hash(pkey, key_len);
584
585 read_lock_bh(&tbl->lock);
586 n = __pneigh_lookup_1(tbl->phash_buckets[hash_val],
587 net, pkey, key_len, dev);
588 read_unlock_bh(&tbl->lock);
589
590 if (n || !creat)
591 goto out;
592
593 ASSERT_RTNL();
594
595 n = kmalloc(sizeof(*n) + key_len, GFP_KERNEL);
596 if (!n)
597 goto out;
598
599 write_pnet(&n->net, net);
600 memcpy(n->key, pkey, key_len);
601 n->dev = dev;
602 if (dev)
603 dev_hold(dev);
604
605 if (tbl->pconstructor && tbl->pconstructor(n)) {
606 if (dev)
607 dev_put(dev);
608 kfree(n);
609 n = NULL;
610 goto out;
611 }
612
613 write_lock_bh(&tbl->lock);
614 n->next = tbl->phash_buckets[hash_val];
615 tbl->phash_buckets[hash_val] = n;
616 write_unlock_bh(&tbl->lock);
617out:
618 return n;
619}
620EXPORT_SYMBOL(pneigh_lookup);
621
622
623int pneigh_delete(struct neigh_table *tbl, struct net *net, const void *pkey,
624 struct net_device *dev)
625{
626 struct pneigh_entry *n, **np;
627 int key_len = tbl->key_len;
628 u32 hash_val = pneigh_hash(pkey, key_len);
629
630 write_lock_bh(&tbl->lock);
631 for (np = &tbl->phash_buckets[hash_val]; (n = *np) != NULL;
632 np = &n->next) {
633 if (!memcmp(n->key, pkey, key_len) && n->dev == dev &&
634 net_eq(pneigh_net(n), net)) {
635 *np = n->next;
636 write_unlock_bh(&tbl->lock);
637 if (tbl->pdestructor)
638 tbl->pdestructor(n);
639 if (n->dev)
640 dev_put(n->dev);
641 kfree(n);
642 return 0;
643 }
644 }
645 write_unlock_bh(&tbl->lock);
646 return -ENOENT;
647}
648
649static int pneigh_ifdown(struct neigh_table *tbl, struct net_device *dev)
650{
651 struct pneigh_entry *n, **np;
652 u32 h;
653
654 for (h = 0; h <= PNEIGH_HASHMASK; h++) {
655 np = &tbl->phash_buckets[h];
656 while ((n = *np) != NULL) {
657 if (!dev || n->dev == dev) {
658 *np = n->next;
659 if (tbl->pdestructor)
660 tbl->pdestructor(n);
661 if (n->dev)
662 dev_put(n->dev);
663 kfree(n);
664 continue;
665 }
666 np = &n->next;
667 }
668 }
669 return -ENOENT;
670}
671
672static void neigh_parms_destroy(struct neigh_parms *parms);
673
674static inline void neigh_parms_put(struct neigh_parms *parms)
675{
676 if (atomic_dec_and_test(&parms->refcnt))
677 neigh_parms_destroy(parms);
678}
679
680/*
681 * neighbour must already be out of the table;
682 *
683 */
684void neigh_destroy(struct neighbour *neigh)
685{
686 struct net_device *dev = neigh->dev;
687
688 NEIGH_CACHE_STAT_INC(neigh->tbl, destroys);
689
690 if (!neigh->dead) {
691 pr_warn("Destroying alive neighbour %p\n", neigh);
692 dump_stack();
693 return;
694 }
695
696 if (neigh_del_timer(neigh))
697 pr_warn("Impossible event\n");
698
699 write_lock_bh(&neigh->lock);
700 __skb_queue_purge(&neigh->arp_queue);
701 write_unlock_bh(&neigh->lock);
702 neigh->arp_queue_len_bytes = 0;
703
704 if (dev->netdev_ops->ndo_neigh_destroy)
705 dev->netdev_ops->ndo_neigh_destroy(dev, neigh);
706
707 dev_put(dev);
708 neigh_parms_put(neigh->parms);
709
710 neigh_dbg(2, "neigh %p is destroyed\n", neigh);
711
712 atomic_dec(&neigh->tbl->entries);
713 kfree_rcu(neigh, rcu);
714}
715EXPORT_SYMBOL(neigh_destroy);
716
717/* Neighbour state is suspicious;
718 disable fast path.
719
720 Called with write_locked neigh.
721 */
722static void neigh_suspect(struct neighbour *neigh)
723{
724 neigh_dbg(2, "neigh %p is suspected\n", neigh);
725
726 neigh->output = neigh->ops->output;
727}
728
729/* Neighbour state is OK;
730 enable fast path.
731
732 Called with write_locked neigh.
733 */
734static void neigh_connect(struct neighbour *neigh)
735{
736 neigh_dbg(2, "neigh %p is connected\n", neigh);
737
738 neigh->output = neigh->ops->connected_output;
739}
740
741static void neigh_periodic_work(struct work_struct *work)
742{
743 struct neigh_table *tbl = container_of(work, struct neigh_table, gc_work.work);
744 struct neighbour *n;
745 struct neighbour __rcu **np;
746 unsigned int i;
747 struct neigh_hash_table *nht;
748
749 NEIGH_CACHE_STAT_INC(tbl, periodic_gc_runs);
750
751 write_lock_bh(&tbl->lock);
752 nht = rcu_dereference_protected(tbl->nht,
753 lockdep_is_held(&tbl->lock));
754
755 /*
756 * periodically recompute ReachableTime from random function
757 */
758
759 if (time_after(jiffies, tbl->last_rand + 300 * HZ)) {
760 struct neigh_parms *p;
761 tbl->last_rand = jiffies;
762 list_for_each_entry(p, &tbl->parms_list, list)
763 p->reachable_time =
764 neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME));
765 }
766
767 if (atomic_read(&tbl->entries) < tbl->gc_thresh1)
768 goto out;
769
770 for (i = 0 ; i < (1 << nht->hash_shift); i++) {
771 np = &nht->hash_buckets[i];
772
773 while ((n = rcu_dereference_protected(*np,
774 lockdep_is_held(&tbl->lock))) != NULL) {
775 unsigned int state;
776
777 write_lock(&n->lock);
778
779 state = n->nud_state;
780 if (state & (NUD_PERMANENT | NUD_IN_TIMER)) {
781 write_unlock(&n->lock);
782 goto next_elt;
783 }
784
785 if (time_before(n->used, n->confirmed))
786 n->used = n->confirmed;
787
788 if (atomic_read(&n->refcnt) == 1 &&
789 (state == NUD_FAILED ||
790 time_after(jiffies, n->used + NEIGH_VAR(n->parms, GC_STALETIME)))) {
791 *np = n->next;
792 n->dead = 1;
793 write_unlock(&n->lock);
794 neigh_cleanup_and_release(n);
795 continue;
796 }
797 write_unlock(&n->lock);
798
799next_elt:
800 np = &n->next;
801 }
802 /*
803 * It's fine to release lock here, even if hash table
804 * grows while we are preempted.
805 */
806 write_unlock_bh(&tbl->lock);
807 cond_resched();
808 write_lock_bh(&tbl->lock);
809 nht = rcu_dereference_protected(tbl->nht,
810 lockdep_is_held(&tbl->lock));
811 }
812out:
813 /* Cycle through all hash buckets every BASE_REACHABLE_TIME/2 ticks.
814 * ARP entry timeouts range from 1/2 BASE_REACHABLE_TIME to 3/2
815 * BASE_REACHABLE_TIME.
816 */
817 queue_delayed_work(system_power_efficient_wq, &tbl->gc_work,
818 NEIGH_VAR(&tbl->parms, BASE_REACHABLE_TIME) >> 1);
819 write_unlock_bh(&tbl->lock);
820}
821
822static __inline__ int neigh_max_probes(struct neighbour *n)
823{
824 struct neigh_parms *p = n->parms;
825 return NEIGH_VAR(p, UCAST_PROBES) + NEIGH_VAR(p, APP_PROBES) +
826 (n->nud_state & NUD_PROBE ? NEIGH_VAR(p, MCAST_REPROBES) :
827 NEIGH_VAR(p, MCAST_PROBES));
828}
829
830static void neigh_invalidate(struct neighbour *neigh)
831 __releases(neigh->lock)
832 __acquires(neigh->lock)
833{
834 struct sk_buff *skb;
835
836 NEIGH_CACHE_STAT_INC(neigh->tbl, res_failed);
837 neigh_dbg(2, "neigh %p is failed\n", neigh);
838 neigh->updated = jiffies;
839
840 /* It is very thin place. report_unreachable is very complicated
841 routine. Particularly, it can hit the same neighbour entry!
842
843 So that, we try to be accurate and avoid dead loop. --ANK
844 */
845 while (neigh->nud_state == NUD_FAILED &&
846 (skb = __skb_dequeue(&neigh->arp_queue)) != NULL) {
847 write_unlock(&neigh->lock);
848 neigh->ops->error_report(neigh, skb);
849 write_lock(&neigh->lock);
850 }
851 __skb_queue_purge(&neigh->arp_queue);
852 neigh->arp_queue_len_bytes = 0;
853}
854
855static void neigh_probe(struct neighbour *neigh)
856 __releases(neigh->lock)
857{
858 struct sk_buff *skb = skb_peek_tail(&neigh->arp_queue);
859 /* keep skb alive even if arp_queue overflows */
860 if (skb)
861 skb = skb_clone(skb, GFP_ATOMIC);
862 write_unlock(&neigh->lock);
863 neigh->ops->solicit(neigh, skb);
864 atomic_inc(&neigh->probes);
865 kfree_skb(skb);
866}
867
868/* Called when a timer expires for a neighbour entry. */
869
870static void neigh_timer_handler(unsigned long arg)
871{
872 unsigned long now, next;
873 struct neighbour *neigh = (struct neighbour *)arg;
874 unsigned int state;
875 int notify = 0;
876
877 write_lock(&neigh->lock);
878
879 state = neigh->nud_state;
880 now = jiffies;
881 next = now + HZ;
882
883 if (!(state & NUD_IN_TIMER))
884 goto out;
885
886 if (state & NUD_REACHABLE) {
887 if (time_before_eq(now,
888 neigh->confirmed + neigh->parms->reachable_time)) {
889 neigh_dbg(2, "neigh %p is still alive\n", neigh);
890 next = neigh->confirmed + neigh->parms->reachable_time;
891 } else if (time_before_eq(now,
892 neigh->used +
893 NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME))) {
894 neigh_dbg(2, "neigh %p is delayed\n", neigh);
895 neigh->nud_state = NUD_DELAY;
896 neigh->updated = jiffies;
897 neigh_suspect(neigh);
898 next = now + NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME);
899 } else {
900 neigh_dbg(2, "neigh %p is suspected\n", neigh);
901 neigh->nud_state = NUD_STALE;
902 neigh->updated = jiffies;
903 neigh_suspect(neigh);
904 notify = 1;
905 }
906 } else if (state & NUD_DELAY) {
907 if (time_before_eq(now,
908 neigh->confirmed +
909 NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME))) {
910 neigh_dbg(2, "neigh %p is now reachable\n", neigh);
911 neigh->nud_state = NUD_REACHABLE;
912 neigh->updated = jiffies;
913 neigh_connect(neigh);
914 notify = 1;
915 next = neigh->confirmed + neigh->parms->reachable_time;
916 } else {
917 neigh_dbg(2, "neigh %p is probed\n", neigh);
918 neigh->nud_state = NUD_PROBE;
919 neigh->updated = jiffies;
920 atomic_set(&neigh->probes, 0);
921 notify = 1;
922 next = now + NEIGH_VAR(neigh->parms, RETRANS_TIME);
923 }
924 } else {
925 /* NUD_PROBE|NUD_INCOMPLETE */
926 next = now + NEIGH_VAR(neigh->parms, RETRANS_TIME);
927 }
928
929 if ((neigh->nud_state & (NUD_INCOMPLETE | NUD_PROBE)) &&
930 atomic_read(&neigh->probes) >= neigh_max_probes(neigh)) {
931 neigh->nud_state = NUD_FAILED;
932 notify = 1;
933 neigh_invalidate(neigh);
934 goto out;
935 }
936
937 if (neigh->nud_state & NUD_IN_TIMER) {
938 if (time_before(next, jiffies + HZ/2))
939 next = jiffies + HZ/2;
940 if (!mod_timer(&neigh->timer, next))
941 neigh_hold(neigh);
942 }
943 if (neigh->nud_state & (NUD_INCOMPLETE | NUD_PROBE)) {
944 neigh_probe(neigh);
945 } else {
946out:
947 write_unlock(&neigh->lock);
948 }
949
950 if (notify)
951 neigh_update_notify(neigh);
952
953 neigh_release(neigh);
954}
955
956int __neigh_event_send(struct neighbour *neigh, struct sk_buff *skb)
957{
958 int rc;
959 bool immediate_probe = false;
960
961 write_lock_bh(&neigh->lock);
962
963 rc = 0;
964 if (neigh->nud_state & (NUD_CONNECTED | NUD_DELAY | NUD_PROBE))
965 goto out_unlock_bh;
966 if (neigh->dead)
967 goto out_dead;
968
969 if (!(neigh->nud_state & (NUD_STALE | NUD_INCOMPLETE))) {
970 if (NEIGH_VAR(neigh->parms, MCAST_PROBES) +
971 NEIGH_VAR(neigh->parms, APP_PROBES)) {
972 unsigned long next, now = jiffies;
973
974 atomic_set(&neigh->probes,
975 NEIGH_VAR(neigh->parms, UCAST_PROBES));
976 neigh->nud_state = NUD_INCOMPLETE;
977 neigh->updated = now;
978 next = now + max(NEIGH_VAR(neigh->parms, RETRANS_TIME),
979 HZ/2);
980 neigh_add_timer(neigh, next);
981 immediate_probe = true;
982 } else {
983 neigh->nud_state = NUD_FAILED;
984 neigh->updated = jiffies;
985 write_unlock_bh(&neigh->lock);
986
987 kfree_skb(skb);
988 return 1;
989 }
990 } else if (neigh->nud_state & NUD_STALE) {
991 neigh_dbg(2, "neigh %p is delayed\n", neigh);
992 neigh->nud_state = NUD_DELAY;
993 neigh->updated = jiffies;
994 neigh_add_timer(neigh, jiffies +
995 NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME));
996 }
997
998 if (neigh->nud_state == NUD_INCOMPLETE) {
999 if (skb) {
1000 while (neigh->arp_queue_len_bytes + skb->truesize >
1001 NEIGH_VAR(neigh->parms, QUEUE_LEN_BYTES)) {
1002 struct sk_buff *buff;
1003
1004 buff = __skb_dequeue(&neigh->arp_queue);
1005 if (!buff)
1006 break;
1007 neigh->arp_queue_len_bytes -= buff->truesize;
1008 kfree_skb(buff);
1009 NEIGH_CACHE_STAT_INC(neigh->tbl, unres_discards);
1010 }
1011 skb_dst_force(skb);
1012 __skb_queue_tail(&neigh->arp_queue, skb);
1013 neigh->arp_queue_len_bytes += skb->truesize;
1014 }
1015 rc = 1;
1016 }
1017out_unlock_bh:
1018 if (immediate_probe)
1019 neigh_probe(neigh);
1020 else
1021 write_unlock(&neigh->lock);
1022 local_bh_enable();
1023 return rc;
1024
1025out_dead:
1026 if (neigh->nud_state & NUD_STALE)
1027 goto out_unlock_bh;
1028 write_unlock_bh(&neigh->lock);
1029 kfree_skb(skb);
1030 return 1;
1031}
1032EXPORT_SYMBOL(__neigh_event_send);
1033
1034static void neigh_update_hhs(struct neighbour *neigh)
1035{
1036 struct hh_cache *hh;
1037 void (*update)(struct hh_cache*, const struct net_device*, const unsigned char *)
1038 = NULL;
1039
1040 if (neigh->dev->header_ops)
1041 update = neigh->dev->header_ops->cache_update;
1042
1043 if (update) {
1044 hh = &neigh->hh;
1045 if (hh->hh_len) {
1046 write_seqlock_bh(&hh->hh_lock);
1047 update(hh, neigh->dev, neigh->ha);
1048 write_sequnlock_bh(&hh->hh_lock);
1049 }
1050 }
1051}
1052
1053
1054
1055/* Generic update routine.
1056 -- lladdr is new lladdr or NULL, if it is not supplied.
1057 -- new is new state.
1058 -- flags
1059 NEIGH_UPDATE_F_OVERRIDE allows to override existing lladdr,
1060 if it is different.
1061 NEIGH_UPDATE_F_WEAK_OVERRIDE will suspect existing "connected"
1062 lladdr instead of overriding it
1063 if it is different.
1064 NEIGH_UPDATE_F_ADMIN means that the change is administrative.
1065
1066 NEIGH_UPDATE_F_OVERRIDE_ISROUTER allows to override existing
1067 NTF_ROUTER flag.
1068 NEIGH_UPDATE_F_ISROUTER indicates if the neighbour is known as
1069 a router.
1070
1071 Caller MUST hold reference count on the entry.
1072 */
1073
1074int neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new,
1075 u32 flags)
1076{
1077 u8 old;
1078 int err;
1079 int notify = 0;
1080 struct net_device *dev;
1081 int update_isrouter = 0;
1082
1083 write_lock_bh(&neigh->lock);
1084
1085 dev = neigh->dev;
1086 old = neigh->nud_state;
1087 err = -EPERM;
1088
1089 if (!(flags & NEIGH_UPDATE_F_ADMIN) &&
1090 (old & (NUD_NOARP | NUD_PERMANENT)))
1091 goto out;
1092 if (neigh->dead)
1093 goto out;
1094
1095 if (!(new & NUD_VALID)) {
1096 neigh_del_timer(neigh);
1097 if (old & NUD_CONNECTED)
1098 neigh_suspect(neigh);
1099 neigh->nud_state = new;
1100 err = 0;
1101 notify = old & NUD_VALID;
1102 if ((old & (NUD_INCOMPLETE | NUD_PROBE)) &&
1103 (new & NUD_FAILED)) {
1104 neigh_invalidate(neigh);
1105 notify = 1;
1106 }
1107 goto out;
1108 }
1109
1110 /* Compare new lladdr with cached one */
1111 if (!dev->addr_len) {
1112 /* First case: device needs no address. */
1113 lladdr = neigh->ha;
1114 } else if (lladdr) {
1115 /* The second case: if something is already cached
1116 and a new address is proposed:
1117 - compare new & old
1118 - if they are different, check override flag
1119 */
1120 if ((old & NUD_VALID) &&
1121 !memcmp(lladdr, neigh->ha, dev->addr_len))
1122 lladdr = neigh->ha;
1123 } else {
1124 /* No address is supplied; if we know something,
1125 use it, otherwise discard the request.
1126 */
1127 err = -EINVAL;
1128 if (!(old & NUD_VALID))
1129 goto out;
1130 lladdr = neigh->ha;
1131 }
1132
1133 if (new & NUD_CONNECTED)
1134 neigh->confirmed = jiffies;
1135 neigh->updated = jiffies;
1136
1137 /* If entry was valid and address is not changed,
1138 do not change entry state, if new one is STALE.
1139 */
1140 err = 0;
1141 update_isrouter = flags & NEIGH_UPDATE_F_OVERRIDE_ISROUTER;
1142 if (old & NUD_VALID) {
1143 if (lladdr != neigh->ha && !(flags & NEIGH_UPDATE_F_OVERRIDE)) {
1144 update_isrouter = 0;
1145 if ((flags & NEIGH_UPDATE_F_WEAK_OVERRIDE) &&
1146 (old & NUD_CONNECTED)) {
1147 lladdr = neigh->ha;
1148 new = NUD_STALE;
1149 } else
1150 goto out;
1151 } else {
1152 if (lladdr == neigh->ha && new == NUD_STALE &&
1153 !(flags & NEIGH_UPDATE_F_ADMIN))
1154 new = old;
1155 }
1156 }
1157
1158 if (new != old) {
1159 neigh_del_timer(neigh);
1160 if (new & NUD_PROBE)
1161 atomic_set(&neigh->probes, 0);
1162 if (new & NUD_IN_TIMER)
1163 neigh_add_timer(neigh, (jiffies +
1164 ((new & NUD_REACHABLE) ?
1165 neigh->parms->reachable_time :
1166 0)));
1167 neigh->nud_state = new;
1168 notify = 1;
1169 }
1170
1171 if (lladdr != neigh->ha) {
1172 write_seqlock(&neigh->ha_lock);
1173 memcpy(&neigh->ha, lladdr, dev->addr_len);
1174 write_sequnlock(&neigh->ha_lock);
1175 neigh_update_hhs(neigh);
1176 if (!(new & NUD_CONNECTED))
1177 neigh->confirmed = jiffies -
1178 (NEIGH_VAR(neigh->parms, BASE_REACHABLE_TIME) << 1);
1179 notify = 1;
1180 }
1181 if (new == old)
1182 goto out;
1183 if (new & NUD_CONNECTED)
1184 neigh_connect(neigh);
1185 else
1186 neigh_suspect(neigh);
1187 if (!(old & NUD_VALID)) {
1188 struct sk_buff *skb;
1189
1190 /* Again: avoid dead loop if something went wrong */
1191
1192 while (neigh->nud_state & NUD_VALID &&
1193 (skb = __skb_dequeue(&neigh->arp_queue)) != NULL) {
1194 struct dst_entry *dst = skb_dst(skb);
1195 struct neighbour *n2, *n1 = neigh;
1196 write_unlock_bh(&neigh->lock);
1197
1198 rcu_read_lock();
1199
1200 /* Why not just use 'neigh' as-is? The problem is that
1201 * things such as shaper, eql, and sch_teql can end up
1202 * using alternative, different, neigh objects to output
1203 * the packet in the output path. So what we need to do
1204 * here is re-lookup the top-level neigh in the path so
1205 * we can reinject the packet there.
1206 */
1207 n2 = NULL;
1208 if (dst) {
1209 n2 = dst_neigh_lookup_skb(dst, skb);
1210 if (n2)
1211 n1 = n2;
1212 }
1213 n1->output(n1, skb);
1214 if (n2)
1215 neigh_release(n2);
1216 rcu_read_unlock();
1217
1218 write_lock_bh(&neigh->lock);
1219 }
1220 __skb_queue_purge(&neigh->arp_queue);
1221 neigh->arp_queue_len_bytes = 0;
1222 }
1223out:
1224 if (update_isrouter) {
1225 neigh->flags = (flags & NEIGH_UPDATE_F_ISROUTER) ?
1226 (neigh->flags | NTF_ROUTER) :
1227 (neigh->flags & ~NTF_ROUTER);
1228 }
1229 write_unlock_bh(&neigh->lock);
1230
1231 if (notify)
1232 neigh_update_notify(neigh);
1233
1234 return err;
1235}
1236EXPORT_SYMBOL(neigh_update);
1237
1238/* Update the neigh to listen temporarily for probe responses, even if it is
1239 * in a NUD_FAILED state. The caller has to hold neigh->lock for writing.
1240 */
1241void __neigh_set_probe_once(struct neighbour *neigh)
1242{
1243 if (neigh->dead)
1244 return;
1245 neigh->updated = jiffies;
1246 if (!(neigh->nud_state & NUD_FAILED))
1247 return;
1248 neigh->nud_state = NUD_INCOMPLETE;
1249 atomic_set(&neigh->probes, neigh_max_probes(neigh));
1250 neigh_add_timer(neigh,
1251 jiffies + NEIGH_VAR(neigh->parms, RETRANS_TIME));
1252}
1253EXPORT_SYMBOL(__neigh_set_probe_once);
1254
1255struct neighbour *neigh_event_ns(struct neigh_table *tbl,
1256 u8 *lladdr, void *saddr,
1257 struct net_device *dev)
1258{
1259 struct neighbour *neigh = __neigh_lookup(tbl, saddr, dev,
1260 lladdr || !dev->addr_len);
1261 if (neigh)
1262 neigh_update(neigh, lladdr, NUD_STALE,
1263 NEIGH_UPDATE_F_OVERRIDE);
1264 return neigh;
1265}
1266EXPORT_SYMBOL(neigh_event_ns);
1267
1268/* called with read_lock_bh(&n->lock); */
1269static void neigh_hh_init(struct neighbour *n)
1270{
1271 struct net_device *dev = n->dev;
1272 __be16 prot = n->tbl->protocol;
1273 struct hh_cache *hh = &n->hh;
1274
1275 write_lock_bh(&n->lock);
1276
1277 /* Only one thread can come in here and initialize the
1278 * hh_cache entry.
1279 */
1280 if (!hh->hh_len)
1281 dev->header_ops->cache(n, hh, prot);
1282
1283 write_unlock_bh(&n->lock);
1284}
1285
1286/* Slow and careful. */
1287
1288int neigh_resolve_output(struct neighbour *neigh, struct sk_buff *skb)
1289{
1290 int rc = 0;
1291
1292 if (!neigh_event_send(neigh, skb)) {
1293 int err;
1294 struct net_device *dev = neigh->dev;
1295 unsigned int seq;
1296
1297 if (dev->header_ops->cache && !neigh->hh.hh_len)
1298 neigh_hh_init(neigh);
1299
1300 do {
1301 __skb_pull(skb, skb_network_offset(skb));
1302 seq = read_seqbegin(&neigh->ha_lock);
1303 err = dev_hard_header(skb, dev, ntohs(skb->protocol),
1304 neigh->ha, NULL, skb->len);
1305 } while (read_seqretry(&neigh->ha_lock, seq));
1306
1307 if (err >= 0)
1308 rc = dev_queue_xmit(skb);
1309 else
1310 goto out_kfree_skb;
1311 }
1312out:
1313 return rc;
1314out_kfree_skb:
1315 rc = -EINVAL;
1316 kfree_skb(skb);
1317 goto out;
1318}
1319EXPORT_SYMBOL(neigh_resolve_output);
1320
1321/* As fast as possible without hh cache */
1322
1323int neigh_connected_output(struct neighbour *neigh, struct sk_buff *skb)
1324{
1325 struct net_device *dev = neigh->dev;
1326 unsigned int seq;
1327 int err;
1328
1329 do {
1330 __skb_pull(skb, skb_network_offset(skb));
1331 seq = read_seqbegin(&neigh->ha_lock);
1332 err = dev_hard_header(skb, dev, ntohs(skb->protocol),
1333 neigh->ha, NULL, skb->len);
1334 } while (read_seqretry(&neigh->ha_lock, seq));
1335
1336 if (err >= 0)
1337 err = dev_queue_xmit(skb);
1338 else {
1339 err = -EINVAL;
1340 kfree_skb(skb);
1341 }
1342 return err;
1343}
1344EXPORT_SYMBOL(neigh_connected_output);
1345
1346int neigh_direct_output(struct neighbour *neigh, struct sk_buff *skb)
1347{
1348 return dev_queue_xmit(skb);
1349}
1350EXPORT_SYMBOL(neigh_direct_output);
1351
1352static void neigh_proxy_process(unsigned long arg)
1353{
1354 struct neigh_table *tbl = (struct neigh_table *)arg;
1355 long sched_next = 0;
1356 unsigned long now = jiffies;
1357 struct sk_buff *skb, *n;
1358
1359 spin_lock(&tbl->proxy_queue.lock);
1360
1361 skb_queue_walk_safe(&tbl->proxy_queue, skb, n) {
1362 long tdif = NEIGH_CB(skb)->sched_next - now;
1363
1364 if (tdif <= 0) {
1365 struct net_device *dev = skb->dev;
1366
1367 __skb_unlink(skb, &tbl->proxy_queue);
1368 if (tbl->proxy_redo && netif_running(dev)) {
1369 rcu_read_lock();
1370 tbl->proxy_redo(skb);
1371 rcu_read_unlock();
1372 } else {
1373 kfree_skb(skb);
1374 }
1375
1376 dev_put(dev);
1377 } else if (!sched_next || tdif < sched_next)
1378 sched_next = tdif;
1379 }
1380 del_timer(&tbl->proxy_timer);
1381 if (sched_next)
1382 mod_timer(&tbl->proxy_timer, jiffies + sched_next);
1383 spin_unlock(&tbl->proxy_queue.lock);
1384}
1385
1386void pneigh_enqueue(struct neigh_table *tbl, struct neigh_parms *p,
1387 struct sk_buff *skb)
1388{
1389 unsigned long now = jiffies;
1390
1391 unsigned long sched_next = now + (prandom_u32() %
1392 NEIGH_VAR(p, PROXY_DELAY));
1393
1394 if (tbl->proxy_queue.qlen > NEIGH_VAR(p, PROXY_QLEN)) {
1395 kfree_skb(skb);
1396 return;
1397 }
1398
1399 NEIGH_CB(skb)->sched_next = sched_next;
1400 NEIGH_CB(skb)->flags |= LOCALLY_ENQUEUED;
1401
1402 spin_lock(&tbl->proxy_queue.lock);
1403 if (del_timer(&tbl->proxy_timer)) {
1404 if (time_before(tbl->proxy_timer.expires, sched_next))
1405 sched_next = tbl->proxy_timer.expires;
1406 }
1407 skb_dst_drop(skb);
1408 dev_hold(skb->dev);
1409 __skb_queue_tail(&tbl->proxy_queue, skb);
1410 mod_timer(&tbl->proxy_timer, sched_next);
1411 spin_unlock(&tbl->proxy_queue.lock);
1412}
1413EXPORT_SYMBOL(pneigh_enqueue);
1414
1415static inline struct neigh_parms *lookup_neigh_parms(struct neigh_table *tbl,
1416 struct net *net, int ifindex)
1417{
1418 struct neigh_parms *p;
1419
1420 list_for_each_entry(p, &tbl->parms_list, list) {
1421 if ((p->dev && p->dev->ifindex == ifindex && net_eq(neigh_parms_net(p), net)) ||
1422 (!p->dev && !ifindex && net_eq(net, &init_net)))
1423 return p;
1424 }
1425
1426 return NULL;
1427}
1428
1429struct neigh_parms *neigh_parms_alloc(struct net_device *dev,
1430 struct neigh_table *tbl)
1431{
1432 struct neigh_parms *p;
1433 struct net *net = dev_net(dev);
1434 const struct net_device_ops *ops = dev->netdev_ops;
1435
1436 p = kmemdup(&tbl->parms, sizeof(*p), GFP_KERNEL);
1437 if (p) {
1438 p->tbl = tbl;
1439 atomic_set(&p->refcnt, 1);
1440 p->reachable_time =
1441 neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME));
1442 dev_hold(dev);
1443 p->dev = dev;
1444 write_pnet(&p->net, net);
1445 p->sysctl_table = NULL;
1446
1447 if (ops->ndo_neigh_setup && ops->ndo_neigh_setup(dev, p)) {
1448 dev_put(dev);
1449 kfree(p);
1450 return NULL;
1451 }
1452
1453 write_lock_bh(&tbl->lock);
1454 list_add(&p->list, &tbl->parms.list);
1455 write_unlock_bh(&tbl->lock);
1456
1457 neigh_parms_data_state_cleanall(p);
1458 }
1459 return p;
1460}
1461EXPORT_SYMBOL(neigh_parms_alloc);
1462
1463static void neigh_rcu_free_parms(struct rcu_head *head)
1464{
1465 struct neigh_parms *parms =
1466 container_of(head, struct neigh_parms, rcu_head);
1467
1468 neigh_parms_put(parms);
1469}
1470
1471void neigh_parms_release(struct neigh_table *tbl, struct neigh_parms *parms)
1472{
1473 if (!parms || parms == &tbl->parms)
1474 return;
1475 write_lock_bh(&tbl->lock);
1476 list_del(&parms->list);
1477 parms->dead = 1;
1478 write_unlock_bh(&tbl->lock);
1479 if (parms->dev)
1480 dev_put(parms->dev);
1481 call_rcu(&parms->rcu_head, neigh_rcu_free_parms);
1482}
1483EXPORT_SYMBOL(neigh_parms_release);
1484
1485static void neigh_parms_destroy(struct neigh_parms *parms)
1486{
1487 kfree(parms);
1488}
1489
1490static struct lock_class_key neigh_table_proxy_queue_class;
1491
1492static struct neigh_table *neigh_tables[NEIGH_NR_TABLES] __read_mostly;
1493
1494void neigh_table_init(int index, struct neigh_table *tbl)
1495{
1496 unsigned long now = jiffies;
1497 unsigned long phsize;
1498
1499 INIT_LIST_HEAD(&tbl->parms_list);
1500 list_add(&tbl->parms.list, &tbl->parms_list);
1501 write_pnet(&tbl->parms.net, &init_net);
1502 atomic_set(&tbl->parms.refcnt, 1);
1503 tbl->parms.reachable_time =
1504 neigh_rand_reach_time(NEIGH_VAR(&tbl->parms, BASE_REACHABLE_TIME));
1505
1506 tbl->stats = alloc_percpu(struct neigh_statistics);
1507 if (!tbl->stats)
1508 panic("cannot create neighbour cache statistics");
1509
1510#ifdef CONFIG_PROC_FS
1511 if (!proc_create_data(tbl->id, 0, init_net.proc_net_stat,
1512 &neigh_stat_seq_fops, tbl))
1513 panic("cannot create neighbour proc dir entry");
1514#endif
1515
1516 RCU_INIT_POINTER(tbl->nht, neigh_hash_alloc(3));
1517
1518 phsize = (PNEIGH_HASHMASK + 1) * sizeof(struct pneigh_entry *);
1519 tbl->phash_buckets = kzalloc(phsize, GFP_KERNEL);
1520
1521 if (!tbl->nht || !tbl->phash_buckets)
1522 panic("cannot allocate neighbour cache hashes");
1523
1524 if (!tbl->entry_size)
1525 tbl->entry_size = ALIGN(offsetof(struct neighbour, primary_key) +
1526 tbl->key_len, NEIGH_PRIV_ALIGN);
1527 else
1528 WARN_ON(tbl->entry_size % NEIGH_PRIV_ALIGN);
1529
1530 rwlock_init(&tbl->lock);
1531 INIT_DEFERRABLE_WORK(&tbl->gc_work, neigh_periodic_work);
1532 queue_delayed_work(system_power_efficient_wq, &tbl->gc_work,
1533 tbl->parms.reachable_time);
1534 setup_timer(&tbl->proxy_timer, neigh_proxy_process, (unsigned long)tbl);
1535 skb_queue_head_init_class(&tbl->proxy_queue,
1536 &neigh_table_proxy_queue_class);
1537
1538 tbl->last_flush = now;
1539 tbl->last_rand = now + tbl->parms.reachable_time * 20;
1540
1541 neigh_tables[index] = tbl;
1542}
1543EXPORT_SYMBOL(neigh_table_init);
1544
1545int neigh_table_clear(int index, struct neigh_table *tbl)
1546{
1547 neigh_tables[index] = NULL;
1548 /* It is not clean... Fix it to unload IPv6 module safely */
1549 cancel_delayed_work_sync(&tbl->gc_work);
1550 del_timer_sync(&tbl->proxy_timer);
1551 pneigh_queue_purge(&tbl->proxy_queue);
1552 neigh_ifdown(tbl, NULL);
1553 if (atomic_read(&tbl->entries))
1554 pr_crit("neighbour leakage\n");
1555
1556 call_rcu(&rcu_dereference_protected(tbl->nht, 1)->rcu,
1557 neigh_hash_free_rcu);
1558 tbl->nht = NULL;
1559
1560 kfree(tbl->phash_buckets);
1561 tbl->phash_buckets = NULL;
1562
1563 remove_proc_entry(tbl->id, init_net.proc_net_stat);
1564
1565 free_percpu(tbl->stats);
1566 tbl->stats = NULL;
1567
1568 return 0;
1569}
1570EXPORT_SYMBOL(neigh_table_clear);
1571
1572static struct neigh_table *neigh_find_table(int family)
1573{
1574 struct neigh_table *tbl = NULL;
1575
1576 switch (family) {
1577 case AF_INET:
1578 tbl = neigh_tables[NEIGH_ARP_TABLE];
1579 break;
1580 case AF_INET6:
1581 tbl = neigh_tables[NEIGH_ND_TABLE];
1582 break;
1583 case AF_DECnet:
1584 tbl = neigh_tables[NEIGH_DN_TABLE];
1585 break;
1586 }
1587
1588 return tbl;
1589}
1590
1591static int neigh_delete(struct sk_buff *skb, struct nlmsghdr *nlh)
1592{
1593 struct net *net = sock_net(skb->sk);
1594 struct ndmsg *ndm;
1595 struct nlattr *dst_attr;
1596 struct neigh_table *tbl;
1597 struct neighbour *neigh;
1598 struct net_device *dev = NULL;
1599 int err = -EINVAL;
1600
1601 ASSERT_RTNL();
1602 if (nlmsg_len(nlh) < sizeof(*ndm))
1603 goto out;
1604
1605 dst_attr = nlmsg_find_attr(nlh, sizeof(*ndm), NDA_DST);
1606 if (dst_attr == NULL)
1607 goto out;
1608
1609 ndm = nlmsg_data(nlh);
1610 if (ndm->ndm_ifindex) {
1611 dev = __dev_get_by_index(net, ndm->ndm_ifindex);
1612 if (dev == NULL) {
1613 err = -ENODEV;
1614 goto out;
1615 }
1616 }
1617
1618 tbl = neigh_find_table(ndm->ndm_family);
1619 if (tbl == NULL)
1620 return -EAFNOSUPPORT;
1621
1622 if (nla_len(dst_attr) < tbl->key_len)
1623 goto out;
1624
1625 if (ndm->ndm_flags & NTF_PROXY) {
1626 err = pneigh_delete(tbl, net, nla_data(dst_attr), dev);
1627 goto out;
1628 }
1629
1630 if (dev == NULL)
1631 goto out;
1632
1633 neigh = neigh_lookup(tbl, nla_data(dst_attr), dev);
1634 if (neigh == NULL) {
1635 err = -ENOENT;
1636 goto out;
1637 }
1638
1639 err = neigh_update(neigh, NULL, NUD_FAILED,
1640 NEIGH_UPDATE_F_OVERRIDE |
1641 NEIGH_UPDATE_F_ADMIN);
1642 neigh_release(neigh);
1643
1644out:
1645 return err;
1646}
1647
1648static int neigh_add(struct sk_buff *skb, struct nlmsghdr *nlh)
1649{
1650 int flags = NEIGH_UPDATE_F_ADMIN | NEIGH_UPDATE_F_OVERRIDE;
1651 struct net *net = sock_net(skb->sk);
1652 struct ndmsg *ndm;
1653 struct nlattr *tb[NDA_MAX+1];
1654 struct neigh_table *tbl;
1655 struct net_device *dev = NULL;
1656 struct neighbour *neigh;
1657 void *dst, *lladdr;
1658 int err;
1659
1660 ASSERT_RTNL();
1661 err = nlmsg_parse(nlh, sizeof(*ndm), tb, NDA_MAX, NULL);
1662 if (err < 0)
1663 goto out;
1664
1665 err = -EINVAL;
1666 if (tb[NDA_DST] == NULL)
1667 goto out;
1668
1669 ndm = nlmsg_data(nlh);
1670 if (ndm->ndm_ifindex) {
1671 dev = __dev_get_by_index(net, ndm->ndm_ifindex);
1672 if (dev == NULL) {
1673 err = -ENODEV;
1674 goto out;
1675 }
1676
1677 if (tb[NDA_LLADDR] && nla_len(tb[NDA_LLADDR]) < dev->addr_len)
1678 goto out;
1679 }
1680
1681 tbl = neigh_find_table(ndm->ndm_family);
1682 if (tbl == NULL)
1683 return -EAFNOSUPPORT;
1684
1685 if (nla_len(tb[NDA_DST]) < tbl->key_len)
1686 goto out;
1687 dst = nla_data(tb[NDA_DST]);
1688 lladdr = tb[NDA_LLADDR] ? nla_data(tb[NDA_LLADDR]) : NULL;
1689
1690 if (ndm->ndm_flags & NTF_PROXY) {
1691 struct pneigh_entry *pn;
1692
1693 err = -ENOBUFS;
1694 pn = pneigh_lookup(tbl, net, dst, dev, 1);
1695 if (pn) {
1696 pn->flags = ndm->ndm_flags;
1697 err = 0;
1698 }
1699 goto out;
1700 }
1701
1702 if (dev == NULL)
1703 goto out;
1704
1705 neigh = neigh_lookup(tbl, dst, dev);
1706 if (neigh == NULL) {
1707 if (!(nlh->nlmsg_flags & NLM_F_CREATE)) {
1708 err = -ENOENT;
1709 goto out;
1710 }
1711
1712 neigh = __neigh_lookup_errno(tbl, dst, dev);
1713 if (IS_ERR(neigh)) {
1714 err = PTR_ERR(neigh);
1715 goto out;
1716 }
1717 } else {
1718 if (nlh->nlmsg_flags & NLM_F_EXCL) {
1719 err = -EEXIST;
1720 neigh_release(neigh);
1721 goto out;
1722 }
1723
1724 if (!(nlh->nlmsg_flags & NLM_F_REPLACE))
1725 flags &= ~NEIGH_UPDATE_F_OVERRIDE;
1726 }
1727
1728 if (ndm->ndm_flags & NTF_USE) {
1729 neigh_event_send(neigh, NULL);
1730 err = 0;
1731 } else
1732 err = neigh_update(neigh, lladdr, ndm->ndm_state, flags);
1733 neigh_release(neigh);
1734
1735out:
1736 return err;
1737}
1738
1739static int neightbl_fill_parms(struct sk_buff *skb, struct neigh_parms *parms)
1740{
1741 struct nlattr *nest;
1742
1743 nest = nla_nest_start(skb, NDTA_PARMS);
1744 if (nest == NULL)
1745 return -ENOBUFS;
1746
1747 if ((parms->dev &&
1748 nla_put_u32(skb, NDTPA_IFINDEX, parms->dev->ifindex)) ||
1749 nla_put_u32(skb, NDTPA_REFCNT, atomic_read(&parms->refcnt)) ||
1750 nla_put_u32(skb, NDTPA_QUEUE_LENBYTES,
1751 NEIGH_VAR(parms, QUEUE_LEN_BYTES)) ||
1752 /* approximative value for deprecated QUEUE_LEN (in packets) */
1753 nla_put_u32(skb, NDTPA_QUEUE_LEN,
1754 NEIGH_VAR(parms, QUEUE_LEN_BYTES) / SKB_TRUESIZE(ETH_FRAME_LEN)) ||
1755 nla_put_u32(skb, NDTPA_PROXY_QLEN, NEIGH_VAR(parms, PROXY_QLEN)) ||
1756 nla_put_u32(skb, NDTPA_APP_PROBES, NEIGH_VAR(parms, APP_PROBES)) ||
1757 nla_put_u32(skb, NDTPA_UCAST_PROBES,
1758 NEIGH_VAR(parms, UCAST_PROBES)) ||
1759 nla_put_u32(skb, NDTPA_MCAST_PROBES,
1760 NEIGH_VAR(parms, MCAST_PROBES)) ||
1761 nla_put_u32(skb, NDTPA_MCAST_REPROBES,
1762 NEIGH_VAR(parms, MCAST_REPROBES)) ||
1763 nla_put_msecs(skb, NDTPA_REACHABLE_TIME, parms->reachable_time,
1764 NDTPA_PAD) ||
1765 nla_put_msecs(skb, NDTPA_BASE_REACHABLE_TIME,
1766 NEIGH_VAR(parms, BASE_REACHABLE_TIME), NDTPA_PAD) ||
1767 nla_put_msecs(skb, NDTPA_GC_STALETIME,
1768 NEIGH_VAR(parms, GC_STALETIME), NDTPA_PAD) ||
1769 nla_put_msecs(skb, NDTPA_DELAY_PROBE_TIME,
1770 NEIGH_VAR(parms, DELAY_PROBE_TIME), NDTPA_PAD) ||
1771 nla_put_msecs(skb, NDTPA_RETRANS_TIME,
1772 NEIGH_VAR(parms, RETRANS_TIME), NDTPA_PAD) ||
1773 nla_put_msecs(skb, NDTPA_ANYCAST_DELAY,
1774 NEIGH_VAR(parms, ANYCAST_DELAY), NDTPA_PAD) ||
1775 nla_put_msecs(skb, NDTPA_PROXY_DELAY,
1776 NEIGH_VAR(parms, PROXY_DELAY), NDTPA_PAD) ||
1777 nla_put_msecs(skb, NDTPA_LOCKTIME,
1778 NEIGH_VAR(parms, LOCKTIME), NDTPA_PAD))
1779 goto nla_put_failure;
1780 return nla_nest_end(skb, nest);
1781
1782nla_put_failure:
1783 nla_nest_cancel(skb, nest);
1784 return -EMSGSIZE;
1785}
1786
1787static int neightbl_fill_info(struct sk_buff *skb, struct neigh_table *tbl,
1788 u32 pid, u32 seq, int type, int flags)
1789{
1790 struct nlmsghdr *nlh;
1791 struct ndtmsg *ndtmsg;
1792
1793 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndtmsg), flags);
1794 if (nlh == NULL)
1795 return -EMSGSIZE;
1796
1797 ndtmsg = nlmsg_data(nlh);
1798
1799 read_lock_bh(&tbl->lock);
1800 ndtmsg->ndtm_family = tbl->family;
1801 ndtmsg->ndtm_pad1 = 0;
1802 ndtmsg->ndtm_pad2 = 0;
1803
1804 if (nla_put_string(skb, NDTA_NAME, tbl->id) ||
1805 nla_put_msecs(skb, NDTA_GC_INTERVAL, tbl->gc_interval, NDTA_PAD) ||
1806 nla_put_u32(skb, NDTA_THRESH1, tbl->gc_thresh1) ||
1807 nla_put_u32(skb, NDTA_THRESH2, tbl->gc_thresh2) ||
1808 nla_put_u32(skb, NDTA_THRESH3, tbl->gc_thresh3))
1809 goto nla_put_failure;
1810 {
1811 unsigned long now = jiffies;
1812 unsigned int flush_delta = now - tbl->last_flush;
1813 unsigned int rand_delta = now - tbl->last_rand;
1814 struct neigh_hash_table *nht;
1815 struct ndt_config ndc = {
1816 .ndtc_key_len = tbl->key_len,
1817 .ndtc_entry_size = tbl->entry_size,
1818 .ndtc_entries = atomic_read(&tbl->entries),
1819 .ndtc_last_flush = jiffies_to_msecs(flush_delta),
1820 .ndtc_last_rand = jiffies_to_msecs(rand_delta),
1821 .ndtc_proxy_qlen = tbl->proxy_queue.qlen,
1822 };
1823
1824 rcu_read_lock_bh();
1825 nht = rcu_dereference_bh(tbl->nht);
1826 ndc.ndtc_hash_rnd = nht->hash_rnd[0];
1827 ndc.ndtc_hash_mask = ((1 << nht->hash_shift) - 1);
1828 rcu_read_unlock_bh();
1829
1830 if (nla_put(skb, NDTA_CONFIG, sizeof(ndc), &ndc))
1831 goto nla_put_failure;
1832 }
1833
1834 {
1835 int cpu;
1836 struct ndt_stats ndst;
1837
1838 memset(&ndst, 0, sizeof(ndst));
1839
1840 for_each_possible_cpu(cpu) {
1841 struct neigh_statistics *st;
1842
1843 st = per_cpu_ptr(tbl->stats, cpu);
1844 ndst.ndts_allocs += st->allocs;
1845 ndst.ndts_destroys += st->destroys;
1846 ndst.ndts_hash_grows += st->hash_grows;
1847 ndst.ndts_res_failed += st->res_failed;
1848 ndst.ndts_lookups += st->lookups;
1849 ndst.ndts_hits += st->hits;
1850 ndst.ndts_rcv_probes_mcast += st->rcv_probes_mcast;
1851 ndst.ndts_rcv_probes_ucast += st->rcv_probes_ucast;
1852 ndst.ndts_periodic_gc_runs += st->periodic_gc_runs;
1853 ndst.ndts_forced_gc_runs += st->forced_gc_runs;
1854 ndst.ndts_table_fulls += st->table_fulls;
1855 }
1856
1857 if (nla_put_64bit(skb, NDTA_STATS, sizeof(ndst), &ndst,
1858 NDTA_PAD))
1859 goto nla_put_failure;
1860 }
1861
1862 BUG_ON(tbl->parms.dev);
1863 if (neightbl_fill_parms(skb, &tbl->parms) < 0)
1864 goto nla_put_failure;
1865
1866 read_unlock_bh(&tbl->lock);
1867 nlmsg_end(skb, nlh);
1868 return 0;
1869
1870nla_put_failure:
1871 read_unlock_bh(&tbl->lock);
1872 nlmsg_cancel(skb, nlh);
1873 return -EMSGSIZE;
1874}
1875
1876static int neightbl_fill_param_info(struct sk_buff *skb,
1877 struct neigh_table *tbl,
1878 struct neigh_parms *parms,
1879 u32 pid, u32 seq, int type,
1880 unsigned int flags)
1881{
1882 struct ndtmsg *ndtmsg;
1883 struct nlmsghdr *nlh;
1884
1885 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndtmsg), flags);
1886 if (nlh == NULL)
1887 return -EMSGSIZE;
1888
1889 ndtmsg = nlmsg_data(nlh);
1890
1891 read_lock_bh(&tbl->lock);
1892 ndtmsg->ndtm_family = tbl->family;
1893 ndtmsg->ndtm_pad1 = 0;
1894 ndtmsg->ndtm_pad2 = 0;
1895
1896 if (nla_put_string(skb, NDTA_NAME, tbl->id) < 0 ||
1897 neightbl_fill_parms(skb, parms) < 0)
1898 goto errout;
1899
1900 read_unlock_bh(&tbl->lock);
1901 nlmsg_end(skb, nlh);
1902 return 0;
1903errout:
1904 read_unlock_bh(&tbl->lock);
1905 nlmsg_cancel(skb, nlh);
1906 return -EMSGSIZE;
1907}
1908
1909static const struct nla_policy nl_neightbl_policy[NDTA_MAX+1] = {
1910 [NDTA_NAME] = { .type = NLA_STRING },
1911 [NDTA_THRESH1] = { .type = NLA_U32 },
1912 [NDTA_THRESH2] = { .type = NLA_U32 },
1913 [NDTA_THRESH3] = { .type = NLA_U32 },
1914 [NDTA_GC_INTERVAL] = { .type = NLA_U64 },
1915 [NDTA_PARMS] = { .type = NLA_NESTED },
1916};
1917
1918static const struct nla_policy nl_ntbl_parm_policy[NDTPA_MAX+1] = {
1919 [NDTPA_IFINDEX] = { .type = NLA_U32 },
1920 [NDTPA_QUEUE_LEN] = { .type = NLA_U32 },
1921 [NDTPA_PROXY_QLEN] = { .type = NLA_U32 },
1922 [NDTPA_APP_PROBES] = { .type = NLA_U32 },
1923 [NDTPA_UCAST_PROBES] = { .type = NLA_U32 },
1924 [NDTPA_MCAST_PROBES] = { .type = NLA_U32 },
1925 [NDTPA_MCAST_REPROBES] = { .type = NLA_U32 },
1926 [NDTPA_BASE_REACHABLE_TIME] = { .type = NLA_U64 },
1927 [NDTPA_GC_STALETIME] = { .type = NLA_U64 },
1928 [NDTPA_DELAY_PROBE_TIME] = { .type = NLA_U64 },
1929 [NDTPA_RETRANS_TIME] = { .type = NLA_U64 },
1930 [NDTPA_ANYCAST_DELAY] = { .type = NLA_U64 },
1931 [NDTPA_PROXY_DELAY] = { .type = NLA_U64 },
1932 [NDTPA_LOCKTIME] = { .type = NLA_U64 },
1933};
1934
1935static int neightbl_set(struct sk_buff *skb, struct nlmsghdr *nlh)
1936{
1937 struct net *net = sock_net(skb->sk);
1938 struct neigh_table *tbl;
1939 struct ndtmsg *ndtmsg;
1940 struct nlattr *tb[NDTA_MAX+1];
1941 bool found = false;
1942 int err, tidx;
1943
1944 err = nlmsg_parse(nlh, sizeof(*ndtmsg), tb, NDTA_MAX,
1945 nl_neightbl_policy);
1946 if (err < 0)
1947 goto errout;
1948
1949 if (tb[NDTA_NAME] == NULL) {
1950 err = -EINVAL;
1951 goto errout;
1952 }
1953
1954 ndtmsg = nlmsg_data(nlh);
1955
1956 for (tidx = 0; tidx < NEIGH_NR_TABLES; tidx++) {
1957 tbl = neigh_tables[tidx];
1958 if (!tbl)
1959 continue;
1960 if (ndtmsg->ndtm_family && tbl->family != ndtmsg->ndtm_family)
1961 continue;
1962 if (nla_strcmp(tb[NDTA_NAME], tbl->id) == 0) {
1963 found = true;
1964 break;
1965 }
1966 }
1967
1968 if (!found)
1969 return -ENOENT;
1970
1971 /*
1972 * We acquire tbl->lock to be nice to the periodic timers and
1973 * make sure they always see a consistent set of values.
1974 */
1975 write_lock_bh(&tbl->lock);
1976
1977 if (tb[NDTA_PARMS]) {
1978 struct nlattr *tbp[NDTPA_MAX+1];
1979 struct neigh_parms *p;
1980 int i, ifindex = 0;
1981
1982 err = nla_parse_nested(tbp, NDTPA_MAX, tb[NDTA_PARMS],
1983 nl_ntbl_parm_policy);
1984 if (err < 0)
1985 goto errout_tbl_lock;
1986
1987 if (tbp[NDTPA_IFINDEX])
1988 ifindex = nla_get_u32(tbp[NDTPA_IFINDEX]);
1989
1990 p = lookup_neigh_parms(tbl, net, ifindex);
1991 if (p == NULL) {
1992 err = -ENOENT;
1993 goto errout_tbl_lock;
1994 }
1995
1996 for (i = 1; i <= NDTPA_MAX; i++) {
1997 if (tbp[i] == NULL)
1998 continue;
1999
2000 switch (i) {
2001 case NDTPA_QUEUE_LEN:
2002 NEIGH_VAR_SET(p, QUEUE_LEN_BYTES,
2003 nla_get_u32(tbp[i]) *
2004 SKB_TRUESIZE(ETH_FRAME_LEN));
2005 break;
2006 case NDTPA_QUEUE_LENBYTES:
2007 NEIGH_VAR_SET(p, QUEUE_LEN_BYTES,
2008 nla_get_u32(tbp[i]));
2009 break;
2010 case NDTPA_PROXY_QLEN:
2011 NEIGH_VAR_SET(p, PROXY_QLEN,
2012 nla_get_u32(tbp[i]));
2013 break;
2014 case NDTPA_APP_PROBES:
2015 NEIGH_VAR_SET(p, APP_PROBES,
2016 nla_get_u32(tbp[i]));
2017 break;
2018 case NDTPA_UCAST_PROBES:
2019 NEIGH_VAR_SET(p, UCAST_PROBES,
2020 nla_get_u32(tbp[i]));
2021 break;
2022 case NDTPA_MCAST_PROBES:
2023 NEIGH_VAR_SET(p, MCAST_PROBES,
2024 nla_get_u32(tbp[i]));
2025 break;
2026 case NDTPA_MCAST_REPROBES:
2027 NEIGH_VAR_SET(p, MCAST_REPROBES,
2028 nla_get_u32(tbp[i]));
2029 break;
2030 case NDTPA_BASE_REACHABLE_TIME:
2031 NEIGH_VAR_SET(p, BASE_REACHABLE_TIME,
2032 nla_get_msecs(tbp[i]));
2033 /* update reachable_time as well, otherwise, the change will
2034 * only be effective after the next time neigh_periodic_work
2035 * decides to recompute it (can be multiple minutes)
2036 */
2037 p->reachable_time =
2038 neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME));
2039 break;
2040 case NDTPA_GC_STALETIME:
2041 NEIGH_VAR_SET(p, GC_STALETIME,
2042 nla_get_msecs(tbp[i]));
2043 break;
2044 case NDTPA_DELAY_PROBE_TIME:
2045 NEIGH_VAR_SET(p, DELAY_PROBE_TIME,
2046 nla_get_msecs(tbp[i]));
2047 call_netevent_notifiers(NETEVENT_DELAY_PROBE_TIME_UPDATE, p);
2048 break;
2049 case NDTPA_RETRANS_TIME:
2050 NEIGH_VAR_SET(p, RETRANS_TIME,
2051 nla_get_msecs(tbp[i]));
2052 break;
2053 case NDTPA_ANYCAST_DELAY:
2054 NEIGH_VAR_SET(p, ANYCAST_DELAY,
2055 nla_get_msecs(tbp[i]));
2056 break;
2057 case NDTPA_PROXY_DELAY:
2058 NEIGH_VAR_SET(p, PROXY_DELAY,
2059 nla_get_msecs(tbp[i]));
2060 break;
2061 case NDTPA_LOCKTIME:
2062 NEIGH_VAR_SET(p, LOCKTIME,
2063 nla_get_msecs(tbp[i]));
2064 break;
2065 }
2066 }
2067 }
2068
2069 err = -ENOENT;
2070 if ((tb[NDTA_THRESH1] || tb[NDTA_THRESH2] ||
2071 tb[NDTA_THRESH3] || tb[NDTA_GC_INTERVAL]) &&
2072 !net_eq(net, &init_net))
2073 goto errout_tbl_lock;
2074
2075 if (tb[NDTA_THRESH1])
2076 tbl->gc_thresh1 = nla_get_u32(tb[NDTA_THRESH1]);
2077
2078 if (tb[NDTA_THRESH2])
2079 tbl->gc_thresh2 = nla_get_u32(tb[NDTA_THRESH2]);
2080
2081 if (tb[NDTA_THRESH3])
2082 tbl->gc_thresh3 = nla_get_u32(tb[NDTA_THRESH3]);
2083
2084 if (tb[NDTA_GC_INTERVAL])
2085 tbl->gc_interval = nla_get_msecs(tb[NDTA_GC_INTERVAL]);
2086
2087 err = 0;
2088
2089errout_tbl_lock:
2090 write_unlock_bh(&tbl->lock);
2091errout:
2092 return err;
2093}
2094
2095static int neightbl_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
2096{
2097 struct net *net = sock_net(skb->sk);
2098 int family, tidx, nidx = 0;
2099 int tbl_skip = cb->args[0];
2100 int neigh_skip = cb->args[1];
2101 struct neigh_table *tbl;
2102
2103 family = ((struct rtgenmsg *) nlmsg_data(cb->nlh))->rtgen_family;
2104
2105 for (tidx = 0; tidx < NEIGH_NR_TABLES; tidx++) {
2106 struct neigh_parms *p;
2107
2108 tbl = neigh_tables[tidx];
2109 if (!tbl)
2110 continue;
2111
2112 if (tidx < tbl_skip || (family && tbl->family != family))
2113 continue;
2114
2115 if (neightbl_fill_info(skb, tbl, NETLINK_CB(cb->skb).portid,
2116 cb->nlh->nlmsg_seq, RTM_NEWNEIGHTBL,
2117 NLM_F_MULTI) < 0)
2118 break;
2119
2120 nidx = 0;
2121 p = list_next_entry(&tbl->parms, list);
2122 list_for_each_entry_from(p, &tbl->parms_list, list) {
2123 if (!net_eq(neigh_parms_net(p), net))
2124 continue;
2125
2126 if (nidx < neigh_skip)
2127 goto next;
2128
2129 if (neightbl_fill_param_info(skb, tbl, p,
2130 NETLINK_CB(cb->skb).portid,
2131 cb->nlh->nlmsg_seq,
2132 RTM_NEWNEIGHTBL,
2133 NLM_F_MULTI) < 0)
2134 goto out;
2135 next:
2136 nidx++;
2137 }
2138
2139 neigh_skip = 0;
2140 }
2141out:
2142 cb->args[0] = tidx;
2143 cb->args[1] = nidx;
2144
2145 return skb->len;
2146}
2147
2148static int neigh_fill_info(struct sk_buff *skb, struct neighbour *neigh,
2149 u32 pid, u32 seq, int type, unsigned int flags)
2150{
2151 unsigned long now = jiffies;
2152 struct nda_cacheinfo ci;
2153 struct nlmsghdr *nlh;
2154 struct ndmsg *ndm;
2155
2156 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndm), flags);
2157 if (nlh == NULL)
2158 return -EMSGSIZE;
2159
2160 ndm = nlmsg_data(nlh);
2161 ndm->ndm_family = neigh->ops->family;
2162 ndm->ndm_pad1 = 0;
2163 ndm->ndm_pad2 = 0;
2164 ndm->ndm_flags = neigh->flags;
2165 ndm->ndm_type = neigh->type;
2166 ndm->ndm_ifindex = neigh->dev->ifindex;
2167
2168 if (nla_put(skb, NDA_DST, neigh->tbl->key_len, neigh->primary_key))
2169 goto nla_put_failure;
2170
2171 read_lock_bh(&neigh->lock);
2172 ndm->ndm_state = neigh->nud_state;
2173 if (neigh->nud_state & NUD_VALID) {
2174 char haddr[MAX_ADDR_LEN];
2175
2176 neigh_ha_snapshot(haddr, neigh, neigh->dev);
2177 if (nla_put(skb, NDA_LLADDR, neigh->dev->addr_len, haddr) < 0) {
2178 read_unlock_bh(&neigh->lock);
2179 goto nla_put_failure;
2180 }
2181 }
2182
2183 ci.ndm_used = jiffies_to_clock_t(now - neigh->used);
2184 ci.ndm_confirmed = jiffies_to_clock_t(now - neigh->confirmed);
2185 ci.ndm_updated = jiffies_to_clock_t(now - neigh->updated);
2186 ci.ndm_refcnt = atomic_read(&neigh->refcnt) - 1;
2187 read_unlock_bh(&neigh->lock);
2188
2189 if (nla_put_u32(skb, NDA_PROBES, atomic_read(&neigh->probes)) ||
2190 nla_put(skb, NDA_CACHEINFO, sizeof(ci), &ci))
2191 goto nla_put_failure;
2192
2193 nlmsg_end(skb, nlh);
2194 return 0;
2195
2196nla_put_failure:
2197 nlmsg_cancel(skb, nlh);
2198 return -EMSGSIZE;
2199}
2200
2201static int pneigh_fill_info(struct sk_buff *skb, struct pneigh_entry *pn,
2202 u32 pid, u32 seq, int type, unsigned int flags,
2203 struct neigh_table *tbl)
2204{
2205 struct nlmsghdr *nlh;
2206 struct ndmsg *ndm;
2207
2208 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndm), flags);
2209 if (nlh == NULL)
2210 return -EMSGSIZE;
2211
2212 ndm = nlmsg_data(nlh);
2213 ndm->ndm_family = tbl->family;
2214 ndm->ndm_pad1 = 0;
2215 ndm->ndm_pad2 = 0;
2216 ndm->ndm_flags = pn->flags | NTF_PROXY;
2217 ndm->ndm_type = RTN_UNICAST;
2218 ndm->ndm_ifindex = pn->dev ? pn->dev->ifindex : 0;
2219 ndm->ndm_state = NUD_NONE;
2220
2221 if (nla_put(skb, NDA_DST, tbl->key_len, pn->key))
2222 goto nla_put_failure;
2223
2224 nlmsg_end(skb, nlh);
2225 return 0;
2226
2227nla_put_failure:
2228 nlmsg_cancel(skb, nlh);
2229 return -EMSGSIZE;
2230}
2231
2232static void neigh_update_notify(struct neighbour *neigh)
2233{
2234 call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, neigh);
2235 __neigh_notify(neigh, RTM_NEWNEIGH, 0);
2236}
2237
2238static bool neigh_master_filtered(struct net_device *dev, int master_idx)
2239{
2240 struct net_device *master;
2241
2242 if (!master_idx)
2243 return false;
2244
2245 master = netdev_master_upper_dev_get(dev);
2246 if (!master || master->ifindex != master_idx)
2247 return true;
2248
2249 return false;
2250}
2251
2252static bool neigh_ifindex_filtered(struct net_device *dev, int filter_idx)
2253{
2254 if (filter_idx && dev->ifindex != filter_idx)
2255 return true;
2256
2257 return false;
2258}
2259
2260static int neigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb,
2261 struct netlink_callback *cb)
2262{
2263 struct net *net = sock_net(skb->sk);
2264 const struct nlmsghdr *nlh = cb->nlh;
2265 struct nlattr *tb[NDA_MAX + 1];
2266 struct neighbour *n;
2267 int rc, h, s_h = cb->args[1];
2268 int idx, s_idx = idx = cb->args[2];
2269 struct neigh_hash_table *nht;
2270 int filter_master_idx = 0, filter_idx = 0;
2271 unsigned int flags = NLM_F_MULTI;
2272 int err;
2273
2274 err = nlmsg_parse(nlh, sizeof(struct ndmsg), tb, NDA_MAX, NULL);
2275 if (!err) {
2276 if (tb[NDA_IFINDEX])
2277 filter_idx = nla_get_u32(tb[NDA_IFINDEX]);
2278
2279 if (tb[NDA_MASTER])
2280 filter_master_idx = nla_get_u32(tb[NDA_MASTER]);
2281
2282 if (filter_idx || filter_master_idx)
2283 flags |= NLM_F_DUMP_FILTERED;
2284 }
2285
2286 rcu_read_lock_bh();
2287 nht = rcu_dereference_bh(tbl->nht);
2288
2289 for (h = s_h; h < (1 << nht->hash_shift); h++) {
2290 if (h > s_h)
2291 s_idx = 0;
2292 for (n = rcu_dereference_bh(nht->hash_buckets[h]), idx = 0;
2293 n != NULL;
2294 n = rcu_dereference_bh(n->next)) {
2295 if (idx < s_idx || !net_eq(dev_net(n->dev), net))
2296 goto next;
2297 if (neigh_ifindex_filtered(n->dev, filter_idx) ||
2298 neigh_master_filtered(n->dev, filter_master_idx))
2299 goto next;
2300 if (neigh_fill_info(skb, n, NETLINK_CB(cb->skb).portid,
2301 cb->nlh->nlmsg_seq,
2302 RTM_NEWNEIGH,
2303 flags) < 0) {
2304 rc = -1;
2305 goto out;
2306 }
2307next:
2308 idx++;
2309 }
2310 }
2311 rc = skb->len;
2312out:
2313 rcu_read_unlock_bh();
2314 cb->args[1] = h;
2315 cb->args[2] = idx;
2316 return rc;
2317}
2318
2319static int pneigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb,
2320 struct netlink_callback *cb)
2321{
2322 struct pneigh_entry *n;
2323 struct net *net = sock_net(skb->sk);
2324 int rc, h, s_h = cb->args[3];
2325 int idx, s_idx = idx = cb->args[4];
2326
2327 read_lock_bh(&tbl->lock);
2328
2329 for (h = s_h; h <= PNEIGH_HASHMASK; h++) {
2330 if (h > s_h)
2331 s_idx = 0;
2332 for (n = tbl->phash_buckets[h], idx = 0; n; n = n->next) {
2333 if (idx < s_idx || pneigh_net(n) != net)
2334 goto next;
2335 if (pneigh_fill_info(skb, n, NETLINK_CB(cb->skb).portid,
2336 cb->nlh->nlmsg_seq,
2337 RTM_NEWNEIGH,
2338 NLM_F_MULTI, tbl) < 0) {
2339 read_unlock_bh(&tbl->lock);
2340 rc = -1;
2341 goto out;
2342 }
2343 next:
2344 idx++;
2345 }
2346 }
2347
2348 read_unlock_bh(&tbl->lock);
2349 rc = skb->len;
2350out:
2351 cb->args[3] = h;
2352 cb->args[4] = idx;
2353 return rc;
2354
2355}
2356
2357static int neigh_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
2358{
2359 struct neigh_table *tbl;
2360 int t, family, s_t;
2361 int proxy = 0;
2362 int err;
2363
2364 family = ((struct rtgenmsg *) nlmsg_data(cb->nlh))->rtgen_family;
2365
2366 /* check for full ndmsg structure presence, family member is
2367 * the same for both structures
2368 */
2369 if (nlmsg_len(cb->nlh) >= sizeof(struct ndmsg) &&
2370 ((struct ndmsg *) nlmsg_data(cb->nlh))->ndm_flags == NTF_PROXY)
2371 proxy = 1;
2372
2373 s_t = cb->args[0];
2374
2375 for (t = 0; t < NEIGH_NR_TABLES; t++) {
2376 tbl = neigh_tables[t];
2377
2378 if (!tbl)
2379 continue;
2380 if (t < s_t || (family && tbl->family != family))
2381 continue;
2382 if (t > s_t)
2383 memset(&cb->args[1], 0, sizeof(cb->args) -
2384 sizeof(cb->args[0]));
2385 if (proxy)
2386 err = pneigh_dump_table(tbl, skb, cb);
2387 else
2388 err = neigh_dump_table(tbl, skb, cb);
2389 if (err < 0)
2390 break;
2391 }
2392
2393 cb->args[0] = t;
2394 return skb->len;
2395}
2396
2397void neigh_for_each(struct neigh_table *tbl, void (*cb)(struct neighbour *, void *), void *cookie)
2398{
2399 int chain;
2400 struct neigh_hash_table *nht;
2401
2402 rcu_read_lock_bh();
2403 nht = rcu_dereference_bh(tbl->nht);
2404
2405 read_lock(&tbl->lock); /* avoid resizes */
2406 for (chain = 0; chain < (1 << nht->hash_shift); chain++) {
2407 struct neighbour *n;
2408
2409 for (n = rcu_dereference_bh(nht->hash_buckets[chain]);
2410 n != NULL;
2411 n = rcu_dereference_bh(n->next))
2412 cb(n, cookie);
2413 }
2414 read_unlock(&tbl->lock);
2415 rcu_read_unlock_bh();
2416}
2417EXPORT_SYMBOL(neigh_for_each);
2418
2419/* The tbl->lock must be held as a writer and BH disabled. */
2420void __neigh_for_each_release(struct neigh_table *tbl,
2421 int (*cb)(struct neighbour *))
2422{
2423 int chain;
2424 struct neigh_hash_table *nht;
2425
2426 nht = rcu_dereference_protected(tbl->nht,
2427 lockdep_is_held(&tbl->lock));
2428 for (chain = 0; chain < (1 << nht->hash_shift); chain++) {
2429 struct neighbour *n;
2430 struct neighbour __rcu **np;
2431
2432 np = &nht->hash_buckets[chain];
2433 while ((n = rcu_dereference_protected(*np,
2434 lockdep_is_held(&tbl->lock))) != NULL) {
2435 int release;
2436
2437 write_lock(&n->lock);
2438 release = cb(n);
2439 if (release) {
2440 rcu_assign_pointer(*np,
2441 rcu_dereference_protected(n->next,
2442 lockdep_is_held(&tbl->lock)));
2443 n->dead = 1;
2444 } else
2445 np = &n->next;
2446 write_unlock(&n->lock);
2447 if (release)
2448 neigh_cleanup_and_release(n);
2449 }
2450 }
2451}
2452EXPORT_SYMBOL(__neigh_for_each_release);
2453
2454int neigh_xmit(int index, struct net_device *dev,
2455 const void *addr, struct sk_buff *skb)
2456{
2457 int err = -EAFNOSUPPORT;
2458 if (likely(index < NEIGH_NR_TABLES)) {
2459 struct neigh_table *tbl;
2460 struct neighbour *neigh;
2461
2462 tbl = neigh_tables[index];
2463 if (!tbl)
2464 goto out;
2465 rcu_read_lock_bh();
2466 neigh = __neigh_lookup_noref(tbl, addr, dev);
2467 if (!neigh)
2468 neigh = __neigh_create(tbl, addr, dev, false);
2469 err = PTR_ERR(neigh);
2470 if (IS_ERR(neigh)) {
2471 rcu_read_unlock_bh();
2472 goto out_kfree_skb;
2473 }
2474 err = neigh->output(neigh, skb);
2475 rcu_read_unlock_bh();
2476 }
2477 else if (index == NEIGH_LINK_TABLE) {
2478 err = dev_hard_header(skb, dev, ntohs(skb->protocol),
2479 addr, NULL, skb->len);
2480 if (err < 0)
2481 goto out_kfree_skb;
2482 err = dev_queue_xmit(skb);
2483 }
2484out:
2485 return err;
2486out_kfree_skb:
2487 kfree_skb(skb);
2488 goto out;
2489}
2490EXPORT_SYMBOL(neigh_xmit);
2491
2492#ifdef CONFIG_PROC_FS
2493
2494static struct neighbour *neigh_get_first(struct seq_file *seq)
2495{
2496 struct neigh_seq_state *state = seq->private;
2497 struct net *net = seq_file_net(seq);
2498 struct neigh_hash_table *nht = state->nht;
2499 struct neighbour *n = NULL;
2500 int bucket = state->bucket;
2501
2502 state->flags &= ~NEIGH_SEQ_IS_PNEIGH;
2503 for (bucket = 0; bucket < (1 << nht->hash_shift); bucket++) {
2504 n = rcu_dereference_bh(nht->hash_buckets[bucket]);
2505
2506 while (n) {
2507 if (!net_eq(dev_net(n->dev), net))
2508 goto next;
2509 if (state->neigh_sub_iter) {
2510 loff_t fakep = 0;
2511 void *v;
2512
2513 v = state->neigh_sub_iter(state, n, &fakep);
2514 if (!v)
2515 goto next;
2516 }
2517 if (!(state->flags & NEIGH_SEQ_SKIP_NOARP))
2518 break;
2519 if (n->nud_state & ~NUD_NOARP)
2520 break;
2521next:
2522 n = rcu_dereference_bh(n->next);
2523 }
2524
2525 if (n)
2526 break;
2527 }
2528 state->bucket = bucket;
2529
2530 return n;
2531}
2532
2533static struct neighbour *neigh_get_next(struct seq_file *seq,
2534 struct neighbour *n,
2535 loff_t *pos)
2536{
2537 struct neigh_seq_state *state = seq->private;
2538 struct net *net = seq_file_net(seq);
2539 struct neigh_hash_table *nht = state->nht;
2540
2541 if (state->neigh_sub_iter) {
2542 void *v = state->neigh_sub_iter(state, n, pos);
2543 if (v)
2544 return n;
2545 }
2546 n = rcu_dereference_bh(n->next);
2547
2548 while (1) {
2549 while (n) {
2550 if (!net_eq(dev_net(n->dev), net))
2551 goto next;
2552 if (state->neigh_sub_iter) {
2553 void *v = state->neigh_sub_iter(state, n, pos);
2554 if (v)
2555 return n;
2556 goto next;
2557 }
2558 if (!(state->flags & NEIGH_SEQ_SKIP_NOARP))
2559 break;
2560
2561 if (n->nud_state & ~NUD_NOARP)
2562 break;
2563next:
2564 n = rcu_dereference_bh(n->next);
2565 }
2566
2567 if (n)
2568 break;
2569
2570 if (++state->bucket >= (1 << nht->hash_shift))
2571 break;
2572
2573 n = rcu_dereference_bh(nht->hash_buckets[state->bucket]);
2574 }
2575
2576 if (n && pos)
2577 --(*pos);
2578 return n;
2579}
2580
2581static struct neighbour *neigh_get_idx(struct seq_file *seq, loff_t *pos)
2582{
2583 struct neighbour *n = neigh_get_first(seq);
2584
2585 if (n) {
2586 --(*pos);
2587 while (*pos) {
2588 n = neigh_get_next(seq, n, pos);
2589 if (!n)
2590 break;
2591 }
2592 }
2593 return *pos ? NULL : n;
2594}
2595
2596static struct pneigh_entry *pneigh_get_first(struct seq_file *seq)
2597{
2598 struct neigh_seq_state *state = seq->private;
2599 struct net *net = seq_file_net(seq);
2600 struct neigh_table *tbl = state->tbl;
2601 struct pneigh_entry *pn = NULL;
2602 int bucket = state->bucket;
2603
2604 state->flags |= NEIGH_SEQ_IS_PNEIGH;
2605 for (bucket = 0; bucket <= PNEIGH_HASHMASK; bucket++) {
2606 pn = tbl->phash_buckets[bucket];
2607 while (pn && !net_eq(pneigh_net(pn), net))
2608 pn = pn->next;
2609 if (pn)
2610 break;
2611 }
2612 state->bucket = bucket;
2613
2614 return pn;
2615}
2616
2617static struct pneigh_entry *pneigh_get_next(struct seq_file *seq,
2618 struct pneigh_entry *pn,
2619 loff_t *pos)
2620{
2621 struct neigh_seq_state *state = seq->private;
2622 struct net *net = seq_file_net(seq);
2623 struct neigh_table *tbl = state->tbl;
2624
2625 do {
2626 pn = pn->next;
2627 } while (pn && !net_eq(pneigh_net(pn), net));
2628
2629 while (!pn) {
2630 if (++state->bucket > PNEIGH_HASHMASK)
2631 break;
2632 pn = tbl->phash_buckets[state->bucket];
2633 while (pn && !net_eq(pneigh_net(pn), net))
2634 pn = pn->next;
2635 if (pn)
2636 break;
2637 }
2638
2639 if (pn && pos)
2640 --(*pos);
2641
2642 return pn;
2643}
2644
2645static struct pneigh_entry *pneigh_get_idx(struct seq_file *seq, loff_t *pos)
2646{
2647 struct pneigh_entry *pn = pneigh_get_first(seq);
2648
2649 if (pn) {
2650 --(*pos);
2651 while (*pos) {
2652 pn = pneigh_get_next(seq, pn, pos);
2653 if (!pn)
2654 break;
2655 }
2656 }
2657 return *pos ? NULL : pn;
2658}
2659
2660static void *neigh_get_idx_any(struct seq_file *seq, loff_t *pos)
2661{
2662 struct neigh_seq_state *state = seq->private;
2663 void *rc;
2664 loff_t idxpos = *pos;
2665
2666 rc = neigh_get_idx(seq, &idxpos);
2667 if (!rc && !(state->flags & NEIGH_SEQ_NEIGH_ONLY))
2668 rc = pneigh_get_idx(seq, &idxpos);
2669
2670 return rc;
2671}
2672
2673void *neigh_seq_start(struct seq_file *seq, loff_t *pos, struct neigh_table *tbl, unsigned int neigh_seq_flags)
2674 __acquires(rcu_bh)
2675{
2676 struct neigh_seq_state *state = seq->private;
2677
2678 state->tbl = tbl;
2679 state->bucket = 0;
2680 state->flags = (neigh_seq_flags & ~NEIGH_SEQ_IS_PNEIGH);
2681
2682 rcu_read_lock_bh();
2683 state->nht = rcu_dereference_bh(tbl->nht);
2684
2685 return *pos ? neigh_get_idx_any(seq, pos) : SEQ_START_TOKEN;
2686}
2687EXPORT_SYMBOL(neigh_seq_start);
2688
2689void *neigh_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2690{
2691 struct neigh_seq_state *state;
2692 void *rc;
2693
2694 if (v == SEQ_START_TOKEN) {
2695 rc = neigh_get_first(seq);
2696 goto out;
2697 }
2698
2699 state = seq->private;
2700 if (!(state->flags & NEIGH_SEQ_IS_PNEIGH)) {
2701 rc = neigh_get_next(seq, v, NULL);
2702 if (rc)
2703 goto out;
2704 if (!(state->flags & NEIGH_SEQ_NEIGH_ONLY))
2705 rc = pneigh_get_first(seq);
2706 } else {
2707 BUG_ON(state->flags & NEIGH_SEQ_NEIGH_ONLY);
2708 rc = pneigh_get_next(seq, v, NULL);
2709 }
2710out:
2711 ++(*pos);
2712 return rc;
2713}
2714EXPORT_SYMBOL(neigh_seq_next);
2715
2716void neigh_seq_stop(struct seq_file *seq, void *v)
2717 __releases(rcu_bh)
2718{
2719 rcu_read_unlock_bh();
2720}
2721EXPORT_SYMBOL(neigh_seq_stop);
2722
2723/* statistics via seq_file */
2724
2725static void *neigh_stat_seq_start(struct seq_file *seq, loff_t *pos)
2726{
2727 struct neigh_table *tbl = seq->private;
2728 int cpu;
2729
2730 if (*pos == 0)
2731 return SEQ_START_TOKEN;
2732
2733 for (cpu = *pos-1; cpu < nr_cpu_ids; ++cpu) {
2734 if (!cpu_possible(cpu))
2735 continue;
2736 *pos = cpu+1;
2737 return per_cpu_ptr(tbl->stats, cpu);
2738 }
2739 return NULL;
2740}
2741
2742static void *neigh_stat_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2743{
2744 struct neigh_table *tbl = seq->private;
2745 int cpu;
2746
2747 for (cpu = *pos; cpu < nr_cpu_ids; ++cpu) {
2748 if (!cpu_possible(cpu))
2749 continue;
2750 *pos = cpu+1;
2751 return per_cpu_ptr(tbl->stats, cpu);
2752 }
2753 return NULL;
2754}
2755
2756static void neigh_stat_seq_stop(struct seq_file *seq, void *v)
2757{
2758
2759}
2760
2761static int neigh_stat_seq_show(struct seq_file *seq, void *v)
2762{
2763 struct neigh_table *tbl = seq->private;
2764 struct neigh_statistics *st = v;
2765
2766 if (v == SEQ_START_TOKEN) {
2767 seq_printf(seq, "entries allocs destroys hash_grows lookups hits res_failed rcv_probes_mcast rcv_probes_ucast periodic_gc_runs forced_gc_runs unresolved_discards table_fulls\n");
2768 return 0;
2769 }
2770
2771 seq_printf(seq, "%08x %08lx %08lx %08lx %08lx %08lx %08lx "
2772 "%08lx %08lx %08lx %08lx %08lx %08lx\n",
2773 atomic_read(&tbl->entries),
2774
2775 st->allocs,
2776 st->destroys,
2777 st->hash_grows,
2778
2779 st->lookups,
2780 st->hits,
2781
2782 st->res_failed,
2783
2784 st->rcv_probes_mcast,
2785 st->rcv_probes_ucast,
2786
2787 st->periodic_gc_runs,
2788 st->forced_gc_runs,
2789 st->unres_discards,
2790 st->table_fulls
2791 );
2792
2793 return 0;
2794}
2795
2796static const struct seq_operations neigh_stat_seq_ops = {
2797 .start = neigh_stat_seq_start,
2798 .next = neigh_stat_seq_next,
2799 .stop = neigh_stat_seq_stop,
2800 .show = neigh_stat_seq_show,
2801};
2802
2803static int neigh_stat_seq_open(struct inode *inode, struct file *file)
2804{
2805 int ret = seq_open(file, &neigh_stat_seq_ops);
2806
2807 if (!ret) {
2808 struct seq_file *sf = file->private_data;
2809 sf->private = PDE_DATA(inode);
2810 }
2811 return ret;
2812};
2813
2814static const struct file_operations neigh_stat_seq_fops = {
2815 .owner = THIS_MODULE,
2816 .open = neigh_stat_seq_open,
2817 .read = seq_read,
2818 .llseek = seq_lseek,
2819 .release = seq_release,
2820};
2821
2822#endif /* CONFIG_PROC_FS */
2823
2824static inline size_t neigh_nlmsg_size(void)
2825{
2826 return NLMSG_ALIGN(sizeof(struct ndmsg))
2827 + nla_total_size(MAX_ADDR_LEN) /* NDA_DST */
2828 + nla_total_size(MAX_ADDR_LEN) /* NDA_LLADDR */
2829 + nla_total_size(sizeof(struct nda_cacheinfo))
2830 + nla_total_size(4); /* NDA_PROBES */
2831}
2832
2833static void __neigh_notify(struct neighbour *n, int type, int flags)
2834{
2835 struct net *net = dev_net(n->dev);
2836 struct sk_buff *skb;
2837 int err = -ENOBUFS;
2838
2839 skb = nlmsg_new(neigh_nlmsg_size(), GFP_ATOMIC);
2840 if (skb == NULL)
2841 goto errout;
2842
2843 err = neigh_fill_info(skb, n, 0, 0, type, flags);
2844 if (err < 0) {
2845 /* -EMSGSIZE implies BUG in neigh_nlmsg_size() */
2846 WARN_ON(err == -EMSGSIZE);
2847 kfree_skb(skb);
2848 goto errout;
2849 }
2850 rtnl_notify(skb, net, 0, RTNLGRP_NEIGH, NULL, GFP_ATOMIC);
2851 return;
2852errout:
2853 if (err < 0)
2854 rtnl_set_sk_err(net, RTNLGRP_NEIGH, err);
2855}
2856
2857void neigh_app_ns(struct neighbour *n)
2858{
2859 __neigh_notify(n, RTM_GETNEIGH, NLM_F_REQUEST);
2860}
2861EXPORT_SYMBOL(neigh_app_ns);
2862
2863#ifdef CONFIG_SYSCTL
2864static int zero;
2865static int int_max = INT_MAX;
2866static int unres_qlen_max = INT_MAX / SKB_TRUESIZE(ETH_FRAME_LEN);
2867
2868static int proc_unres_qlen(struct ctl_table *ctl, int write,
2869 void __user *buffer, size_t *lenp, loff_t *ppos)
2870{
2871 int size, ret;
2872 struct ctl_table tmp = *ctl;
2873
2874 tmp.extra1 = &zero;
2875 tmp.extra2 = &unres_qlen_max;
2876 tmp.data = &size;
2877
2878 size = *(int *)ctl->data / SKB_TRUESIZE(ETH_FRAME_LEN);
2879 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
2880
2881 if (write && !ret)
2882 *(int *)ctl->data = size * SKB_TRUESIZE(ETH_FRAME_LEN);
2883 return ret;
2884}
2885
2886static struct neigh_parms *neigh_get_dev_parms_rcu(struct net_device *dev,
2887 int family)
2888{
2889 switch (family) {
2890 case AF_INET:
2891 return __in_dev_arp_parms_get_rcu(dev);
2892 case AF_INET6:
2893 return __in6_dev_nd_parms_get_rcu(dev);
2894 }
2895 return NULL;
2896}
2897
2898static void neigh_copy_dflt_parms(struct net *net, struct neigh_parms *p,
2899 int index)
2900{
2901 struct net_device *dev;
2902 int family = neigh_parms_family(p);
2903
2904 rcu_read_lock();
2905 for_each_netdev_rcu(net, dev) {
2906 struct neigh_parms *dst_p =
2907 neigh_get_dev_parms_rcu(dev, family);
2908
2909 if (dst_p && !test_bit(index, dst_p->data_state))
2910 dst_p->data[index] = p->data[index];
2911 }
2912 rcu_read_unlock();
2913}
2914
2915static void neigh_proc_update(struct ctl_table *ctl, int write)
2916{
2917 struct net_device *dev = ctl->extra1;
2918 struct neigh_parms *p = ctl->extra2;
2919 struct net *net = neigh_parms_net(p);
2920 int index = (int *) ctl->data - p->data;
2921
2922 if (!write)
2923 return;
2924
2925 set_bit(index, p->data_state);
2926 if (index == NEIGH_VAR_DELAY_PROBE_TIME)
2927 call_netevent_notifiers(NETEVENT_DELAY_PROBE_TIME_UPDATE, p);
2928 if (!dev) /* NULL dev means this is default value */
2929 neigh_copy_dflt_parms(net, p, index);
2930}
2931
2932static int neigh_proc_dointvec_zero_intmax(struct ctl_table *ctl, int write,
2933 void __user *buffer,
2934 size_t *lenp, loff_t *ppos)
2935{
2936 struct ctl_table tmp = *ctl;
2937 int ret;
2938
2939 tmp.extra1 = &zero;
2940 tmp.extra2 = &int_max;
2941
2942 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
2943 neigh_proc_update(ctl, write);
2944 return ret;
2945}
2946
2947int neigh_proc_dointvec(struct ctl_table *ctl, int write,
2948 void __user *buffer, size_t *lenp, loff_t *ppos)
2949{
2950 int ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
2951
2952 neigh_proc_update(ctl, write);
2953 return ret;
2954}
2955EXPORT_SYMBOL(neigh_proc_dointvec);
2956
2957int neigh_proc_dointvec_jiffies(struct ctl_table *ctl, int write,
2958 void __user *buffer,
2959 size_t *lenp, loff_t *ppos)
2960{
2961 int ret = proc_dointvec_jiffies(ctl, write, buffer, lenp, ppos);
2962
2963 neigh_proc_update(ctl, write);
2964 return ret;
2965}
2966EXPORT_SYMBOL(neigh_proc_dointvec_jiffies);
2967
2968static int neigh_proc_dointvec_userhz_jiffies(struct ctl_table *ctl, int write,
2969 void __user *buffer,
2970 size_t *lenp, loff_t *ppos)
2971{
2972 int ret = proc_dointvec_userhz_jiffies(ctl, write, buffer, lenp, ppos);
2973
2974 neigh_proc_update(ctl, write);
2975 return ret;
2976}
2977
2978int neigh_proc_dointvec_ms_jiffies(struct ctl_table *ctl, int write,
2979 void __user *buffer,
2980 size_t *lenp, loff_t *ppos)
2981{
2982 int ret = proc_dointvec_ms_jiffies(ctl, write, buffer, lenp, ppos);
2983
2984 neigh_proc_update(ctl, write);
2985 return ret;
2986}
2987EXPORT_SYMBOL(neigh_proc_dointvec_ms_jiffies);
2988
2989static int neigh_proc_dointvec_unres_qlen(struct ctl_table *ctl, int write,
2990 void __user *buffer,
2991 size_t *lenp, loff_t *ppos)
2992{
2993 int ret = proc_unres_qlen(ctl, write, buffer, lenp, ppos);
2994
2995 neigh_proc_update(ctl, write);
2996 return ret;
2997}
2998
2999static int neigh_proc_base_reachable_time(struct ctl_table *ctl, int write,
3000 void __user *buffer,
3001 size_t *lenp, loff_t *ppos)
3002{
3003 struct neigh_parms *p = ctl->extra2;
3004 int ret;
3005
3006 if (strcmp(ctl->procname, "base_reachable_time") == 0)
3007 ret = neigh_proc_dointvec_jiffies(ctl, write, buffer, lenp, ppos);
3008 else if (strcmp(ctl->procname, "base_reachable_time_ms") == 0)
3009 ret = neigh_proc_dointvec_ms_jiffies(ctl, write, buffer, lenp, ppos);
3010 else
3011 ret = -1;
3012
3013 if (write && ret == 0) {
3014 /* update reachable_time as well, otherwise, the change will
3015 * only be effective after the next time neigh_periodic_work
3016 * decides to recompute it
3017 */
3018 p->reachable_time =
3019 neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME));
3020 }
3021 return ret;
3022}
3023
3024#define NEIGH_PARMS_DATA_OFFSET(index) \
3025 (&((struct neigh_parms *) 0)->data[index])
3026
3027#define NEIGH_SYSCTL_ENTRY(attr, data_attr, name, mval, proc) \
3028 [NEIGH_VAR_ ## attr] = { \
3029 .procname = name, \
3030 .data = NEIGH_PARMS_DATA_OFFSET(NEIGH_VAR_ ## data_attr), \
3031 .maxlen = sizeof(int), \
3032 .mode = mval, \
3033 .proc_handler = proc, \
3034 }
3035
3036#define NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(attr, name) \
3037 NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_zero_intmax)
3038
3039#define NEIGH_SYSCTL_JIFFIES_ENTRY(attr, name) \
3040 NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_jiffies)
3041
3042#define NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(attr, name) \
3043 NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_userhz_jiffies)
3044
3045#define NEIGH_SYSCTL_MS_JIFFIES_ENTRY(attr, name) \
3046 NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_ms_jiffies)
3047
3048#define NEIGH_SYSCTL_MS_JIFFIES_REUSED_ENTRY(attr, data_attr, name) \
3049 NEIGH_SYSCTL_ENTRY(attr, data_attr, name, 0644, neigh_proc_dointvec_ms_jiffies)
3050
3051#define NEIGH_SYSCTL_UNRES_QLEN_REUSED_ENTRY(attr, data_attr, name) \
3052 NEIGH_SYSCTL_ENTRY(attr, data_attr, name, 0644, neigh_proc_dointvec_unres_qlen)
3053
3054static struct neigh_sysctl_table {
3055 struct ctl_table_header *sysctl_header;
3056 struct ctl_table neigh_vars[NEIGH_VAR_MAX + 1];
3057} neigh_sysctl_template __read_mostly = {
3058 .neigh_vars = {
3059 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(MCAST_PROBES, "mcast_solicit"),
3060 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(UCAST_PROBES, "ucast_solicit"),
3061 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(APP_PROBES, "app_solicit"),
3062 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(MCAST_REPROBES, "mcast_resolicit"),
3063 NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(RETRANS_TIME, "retrans_time"),
3064 NEIGH_SYSCTL_JIFFIES_ENTRY(BASE_REACHABLE_TIME, "base_reachable_time"),
3065 NEIGH_SYSCTL_JIFFIES_ENTRY(DELAY_PROBE_TIME, "delay_first_probe_time"),
3066 NEIGH_SYSCTL_JIFFIES_ENTRY(GC_STALETIME, "gc_stale_time"),
3067 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(QUEUE_LEN_BYTES, "unres_qlen_bytes"),
3068 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(PROXY_QLEN, "proxy_qlen"),
3069 NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(ANYCAST_DELAY, "anycast_delay"),
3070 NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(PROXY_DELAY, "proxy_delay"),
3071 NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(LOCKTIME, "locktime"),
3072 NEIGH_SYSCTL_UNRES_QLEN_REUSED_ENTRY(QUEUE_LEN, QUEUE_LEN_BYTES, "unres_qlen"),
3073 NEIGH_SYSCTL_MS_JIFFIES_REUSED_ENTRY(RETRANS_TIME_MS, RETRANS_TIME, "retrans_time_ms"),
3074 NEIGH_SYSCTL_MS_JIFFIES_REUSED_ENTRY(BASE_REACHABLE_TIME_MS, BASE_REACHABLE_TIME, "base_reachable_time_ms"),
3075 [NEIGH_VAR_GC_INTERVAL] = {
3076 .procname = "gc_interval",
3077 .maxlen = sizeof(int),
3078 .mode = 0644,
3079 .proc_handler = proc_dointvec_jiffies,
3080 },
3081 [NEIGH_VAR_GC_THRESH1] = {
3082 .procname = "gc_thresh1",
3083 .maxlen = sizeof(int),
3084 .mode = 0644,
3085 .extra1 = &zero,
3086 .extra2 = &int_max,
3087 .proc_handler = proc_dointvec_minmax,
3088 },
3089 [NEIGH_VAR_GC_THRESH2] = {
3090 .procname = "gc_thresh2",
3091 .maxlen = sizeof(int),
3092 .mode = 0644,
3093 .extra1 = &zero,
3094 .extra2 = &int_max,
3095 .proc_handler = proc_dointvec_minmax,
3096 },
3097 [NEIGH_VAR_GC_THRESH3] = {
3098 .procname = "gc_thresh3",
3099 .maxlen = sizeof(int),
3100 .mode = 0644,
3101 .extra1 = &zero,
3102 .extra2 = &int_max,
3103 .proc_handler = proc_dointvec_minmax,
3104 },
3105 {},
3106 },
3107};
3108
3109int neigh_sysctl_register(struct net_device *dev, struct neigh_parms *p,
3110 proc_handler *handler)
3111{
3112 int i;
3113 struct neigh_sysctl_table *t;
3114 const char *dev_name_source;
3115 char neigh_path[ sizeof("net//neigh/") + IFNAMSIZ + IFNAMSIZ ];
3116 char *p_name;
3117
3118 t = kmemdup(&neigh_sysctl_template, sizeof(*t), GFP_KERNEL);
3119 if (!t)
3120 goto err;
3121
3122 for (i = 0; i < NEIGH_VAR_GC_INTERVAL; i++) {
3123 t->neigh_vars[i].data += (long) p;
3124 t->neigh_vars[i].extra1 = dev;
3125 t->neigh_vars[i].extra2 = p;
3126 }
3127
3128 if (dev) {
3129 dev_name_source = dev->name;
3130 /* Terminate the table early */
3131 memset(&t->neigh_vars[NEIGH_VAR_GC_INTERVAL], 0,
3132 sizeof(t->neigh_vars[NEIGH_VAR_GC_INTERVAL]));
3133 } else {
3134 struct neigh_table *tbl = p->tbl;
3135 dev_name_source = "default";
3136 t->neigh_vars[NEIGH_VAR_GC_INTERVAL].data = &tbl->gc_interval;
3137 t->neigh_vars[NEIGH_VAR_GC_THRESH1].data = &tbl->gc_thresh1;
3138 t->neigh_vars[NEIGH_VAR_GC_THRESH2].data = &tbl->gc_thresh2;
3139 t->neigh_vars[NEIGH_VAR_GC_THRESH3].data = &tbl->gc_thresh3;
3140 }
3141
3142 if (handler) {
3143 /* RetransTime */
3144 t->neigh_vars[NEIGH_VAR_RETRANS_TIME].proc_handler = handler;
3145 /* ReachableTime */
3146 t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME].proc_handler = handler;
3147 /* RetransTime (in milliseconds)*/
3148 t->neigh_vars[NEIGH_VAR_RETRANS_TIME_MS].proc_handler = handler;
3149 /* ReachableTime (in milliseconds) */
3150 t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME_MS].proc_handler = handler;
3151 } else {
3152 /* Those handlers will update p->reachable_time after
3153 * base_reachable_time(_ms) is set to ensure the new timer starts being
3154 * applied after the next neighbour update instead of waiting for
3155 * neigh_periodic_work to update its value (can be multiple minutes)
3156 * So any handler that replaces them should do this as well
3157 */
3158 /* ReachableTime */
3159 t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME].proc_handler =
3160 neigh_proc_base_reachable_time;
3161 /* ReachableTime (in milliseconds) */
3162 t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME_MS].proc_handler =
3163 neigh_proc_base_reachable_time;
3164 }
3165
3166 /* Don't export sysctls to unprivileged users */
3167 if (neigh_parms_net(p)->user_ns != &init_user_ns)
3168 t->neigh_vars[0].procname = NULL;
3169
3170 switch (neigh_parms_family(p)) {
3171 case AF_INET:
3172 p_name = "ipv4";
3173 break;
3174 case AF_INET6:
3175 p_name = "ipv6";
3176 break;
3177 default:
3178 BUG();
3179 }
3180
3181 snprintf(neigh_path, sizeof(neigh_path), "net/%s/neigh/%s",
3182 p_name, dev_name_source);
3183 t->sysctl_header =
3184 register_net_sysctl(neigh_parms_net(p), neigh_path, t->neigh_vars);
3185 if (!t->sysctl_header)
3186 goto free;
3187
3188 p->sysctl_table = t;
3189 return 0;
3190
3191free:
3192 kfree(t);
3193err:
3194 return -ENOBUFS;
3195}
3196EXPORT_SYMBOL(neigh_sysctl_register);
3197
3198void neigh_sysctl_unregister(struct neigh_parms *p)
3199{
3200 if (p->sysctl_table) {
3201 struct neigh_sysctl_table *t = p->sysctl_table;
3202 p->sysctl_table = NULL;
3203 unregister_net_sysctl_table(t->sysctl_header);
3204 kfree(t);
3205 }
3206}
3207EXPORT_SYMBOL(neigh_sysctl_unregister);
3208
3209#endif /* CONFIG_SYSCTL */
3210
3211static int __init neigh_init(void)
3212{
3213 rtnl_register(PF_UNSPEC, RTM_NEWNEIGH, neigh_add, NULL, NULL);
3214 rtnl_register(PF_UNSPEC, RTM_DELNEIGH, neigh_delete, NULL, NULL);
3215 rtnl_register(PF_UNSPEC, RTM_GETNEIGH, NULL, neigh_dump_info, NULL);
3216
3217 rtnl_register(PF_UNSPEC, RTM_GETNEIGHTBL, NULL, neightbl_dump_info,
3218 NULL);
3219 rtnl_register(PF_UNSPEC, RTM_SETNEIGHTBL, neightbl_set, NULL, NULL);
3220
3221 return 0;
3222}
3223
3224subsys_initcall(neigh_init);
3225