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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
59static struct neigh_table *neigh_tables;
60#ifdef CONFIG_PROC_FS
61static const struct file_operations neigh_stat_seq_fops;
62#endif
63
64/*
65 Neighbour hash table buckets are protected with rwlock tbl->lock.
66
67 - All the scans/updates to hash buckets MUST be made under this lock.
68 - NOTHING clever should be made under this lock: no callbacks
69 to protocol backends, no attempts to send something to network.
70 It will result in deadlocks, if backend/driver wants to use neighbour
71 cache.
72 - If the entry requires some non-trivial actions, increase
73 its reference count and release table lock.
74
75 Neighbour entries are protected:
76 - with reference count.
77 - with rwlock neigh->lock
78
79 Reference count prevents destruction.
80
81 neigh->lock mainly serializes ll address data and its validity state.
82 However, the same lock is used to protect another entry fields:
83 - timer
84 - resolution queue
85
86 Again, nothing clever shall be made under neigh->lock,
87 the most complicated procedure, which we allow is dev->hard_header.
88 It is supposed, that dev->hard_header is simplistic and does
89 not make callbacks to neighbour tables.
90
91 The last lock is neigh_tbl_lock. It is pure SMP lock, protecting
92 list of neighbour tables. This list is used only in process context,
93 */
94
95static DEFINE_RWLOCK(neigh_tbl_lock);
96
97static int neigh_blackhole(struct neighbour *neigh, struct sk_buff *skb)
98{
99 kfree_skb(skb);
100 return -ENETDOWN;
101}
102
103static void neigh_cleanup_and_release(struct neighbour *neigh)
104{
105 if (neigh->parms->neigh_cleanup)
106 neigh->parms->neigh_cleanup(neigh);
107
108 __neigh_notify(neigh, RTM_DELNEIGH, 0);
109 neigh_release(neigh);
110}
111
112/*
113 * It is random distribution in the interval (1/2)*base...(3/2)*base.
114 * It corresponds to default IPv6 settings and is not overridable,
115 * because it is really reasonable choice.
116 */
117
118unsigned long neigh_rand_reach_time(unsigned long base)
119{
120 return base ? (prandom_u32() % base) + (base >> 1) : 0;
121}
122EXPORT_SYMBOL(neigh_rand_reach_time);
123
124
125static int neigh_forced_gc(struct neigh_table *tbl)
126{
127 int shrunk = 0;
128 int i;
129 struct neigh_hash_table *nht;
130
131 NEIGH_CACHE_STAT_INC(tbl, forced_gc_runs);
132
133 write_lock_bh(&tbl->lock);
134 nht = rcu_dereference_protected(tbl->nht,
135 lockdep_is_held(&tbl->lock));
136 for (i = 0; i < (1 << nht->hash_shift); i++) {
137 struct neighbour *n;
138 struct neighbour __rcu **np;
139
140 np = &nht->hash_buckets[i];
141 while ((n = rcu_dereference_protected(*np,
142 lockdep_is_held(&tbl->lock))) != NULL) {
143 /* Neighbour record may be discarded if:
144 * - nobody refers to it.
145 * - it is not permanent
146 */
147 write_lock(&n->lock);
148 if (atomic_read(&n->refcnt) == 1 &&
149 !(n->nud_state & NUD_PERMANENT)) {
150 rcu_assign_pointer(*np,
151 rcu_dereference_protected(n->next,
152 lockdep_is_held(&tbl->lock)));
153 n->dead = 1;
154 shrunk = 1;
155 write_unlock(&n->lock);
156 neigh_cleanup_and_release(n);
157 continue;
158 }
159 write_unlock(&n->lock);
160 np = &n->next;
161 }
162 }
163
164 tbl->last_flush = jiffies;
165
166 write_unlock_bh(&tbl->lock);
167
168 return shrunk;
169}
170
171static void neigh_add_timer(struct neighbour *n, unsigned long when)
172{
173 neigh_hold(n);
174 if (unlikely(mod_timer(&n->timer, when))) {
175 printk("NEIGH: BUG, double timer add, state is %x\n",
176 n->nud_state);
177 dump_stack();
178 }
179}
180
181static int neigh_del_timer(struct neighbour *n)
182{
183 if ((n->nud_state & NUD_IN_TIMER) &&
184 del_timer(&n->timer)) {
185 neigh_release(n);
186 return 1;
187 }
188 return 0;
189}
190
191static void pneigh_queue_purge(struct sk_buff_head *list)
192{
193 struct sk_buff *skb;
194
195 while ((skb = skb_dequeue(list)) != NULL) {
196 dev_put(skb->dev);
197 kfree_skb(skb);
198 }
199}
200
201static void neigh_flush_dev(struct neigh_table *tbl, struct net_device *dev)
202{
203 int i;
204 struct neigh_hash_table *nht;
205
206 nht = rcu_dereference_protected(tbl->nht,
207 lockdep_is_held(&tbl->lock));
208
209 for (i = 0; i < (1 << nht->hash_shift); i++) {
210 struct neighbour *n;
211 struct neighbour __rcu **np = &nht->hash_buckets[i];
212
213 while ((n = rcu_dereference_protected(*np,
214 lockdep_is_held(&tbl->lock))) != NULL) {
215 if (dev && n->dev != dev) {
216 np = &n->next;
217 continue;
218 }
219 rcu_assign_pointer(*np,
220 rcu_dereference_protected(n->next,
221 lockdep_is_held(&tbl->lock)));
222 write_lock(&n->lock);
223 neigh_del_timer(n);
224 n->dead = 1;
225
226 if (atomic_read(&n->refcnt) != 1) {
227 /* The most unpleasant situation.
228 We must destroy neighbour entry,
229 but someone still uses it.
230
231 The destroy will be delayed until
232 the last user releases us, but
233 we must kill timers etc. and move
234 it to safe state.
235 */
236 __skb_queue_purge(&n->arp_queue);
237 n->arp_queue_len_bytes = 0;
238 n->output = neigh_blackhole;
239 if (n->nud_state & NUD_VALID)
240 n->nud_state = NUD_NOARP;
241 else
242 n->nud_state = NUD_NONE;
243 neigh_dbg(2, "neigh %p is stray\n", n);
244 }
245 write_unlock(&n->lock);
246 neigh_cleanup_and_release(n);
247 }
248 }
249}
250
251void neigh_changeaddr(struct neigh_table *tbl, struct net_device *dev)
252{
253 write_lock_bh(&tbl->lock);
254 neigh_flush_dev(tbl, dev);
255 write_unlock_bh(&tbl->lock);
256}
257EXPORT_SYMBOL(neigh_changeaddr);
258
259int neigh_ifdown(struct neigh_table *tbl, struct net_device *dev)
260{
261 write_lock_bh(&tbl->lock);
262 neigh_flush_dev(tbl, dev);
263 pneigh_ifdown(tbl, dev);
264 write_unlock_bh(&tbl->lock);
265
266 del_timer_sync(&tbl->proxy_timer);
267 pneigh_queue_purge(&tbl->proxy_queue);
268 return 0;
269}
270EXPORT_SYMBOL(neigh_ifdown);
271
272static struct neighbour *neigh_alloc(struct neigh_table *tbl, struct net_device *dev)
273{
274 struct neighbour *n = NULL;
275 unsigned long now = jiffies;
276 int entries;
277
278 entries = atomic_inc_return(&tbl->entries) - 1;
279 if (entries >= tbl->gc_thresh3 ||
280 (entries >= tbl->gc_thresh2 &&
281 time_after(now, tbl->last_flush + 5 * HZ))) {
282 if (!neigh_forced_gc(tbl) &&
283 entries >= tbl->gc_thresh3)
284 goto out_entries;
285 }
286
287 n = kzalloc(tbl->entry_size + dev->neigh_priv_len, GFP_ATOMIC);
288 if (!n)
289 goto out_entries;
290
291 __skb_queue_head_init(&n->arp_queue);
292 rwlock_init(&n->lock);
293 seqlock_init(&n->ha_lock);
294 n->updated = n->used = now;
295 n->nud_state = NUD_NONE;
296 n->output = neigh_blackhole;
297 seqlock_init(&n->hh.hh_lock);
298 n->parms = neigh_parms_clone(&tbl->parms);
299 setup_timer(&n->timer, neigh_timer_handler, (unsigned long)n);
300
301 NEIGH_CACHE_STAT_INC(tbl, allocs);
302 n->tbl = tbl;
303 atomic_set(&n->refcnt, 1);
304 n->dead = 1;
305out:
306 return n;
307
308out_entries:
309 atomic_dec(&tbl->entries);
310 goto out;
311}
312
313static void neigh_get_hash_rnd(u32 *x)
314{
315 get_random_bytes(x, sizeof(*x));
316 *x |= 1;
317}
318
319static struct neigh_hash_table *neigh_hash_alloc(unsigned int shift)
320{
321 size_t size = (1 << shift) * sizeof(struct neighbour *);
322 struct neigh_hash_table *ret;
323 struct neighbour __rcu **buckets;
324 int i;
325
326 ret = kmalloc(sizeof(*ret), GFP_ATOMIC);
327 if (!ret)
328 return NULL;
329 if (size <= PAGE_SIZE)
330 buckets = kzalloc(size, GFP_ATOMIC);
331 else
332 buckets = (struct neighbour __rcu **)
333 __get_free_pages(GFP_ATOMIC | __GFP_ZERO,
334 get_order(size));
335 if (!buckets) {
336 kfree(ret);
337 return NULL;
338 }
339 ret->hash_buckets = buckets;
340 ret->hash_shift = shift;
341 for (i = 0; i < NEIGH_NUM_HASH_RND; i++)
342 neigh_get_hash_rnd(&ret->hash_rnd[i]);
343 return ret;
344}
345
346static void neigh_hash_free_rcu(struct rcu_head *head)
347{
348 struct neigh_hash_table *nht = container_of(head,
349 struct neigh_hash_table,
350 rcu);
351 size_t size = (1 << nht->hash_shift) * sizeof(struct neighbour *);
352 struct neighbour __rcu **buckets = nht->hash_buckets;
353
354 if (size <= PAGE_SIZE)
355 kfree(buckets);
356 else
357 free_pages((unsigned long)buckets, get_order(size));
358 kfree(nht);
359}
360
361static struct neigh_hash_table *neigh_hash_grow(struct neigh_table *tbl,
362 unsigned long new_shift)
363{
364 unsigned int i, hash;
365 struct neigh_hash_table *new_nht, *old_nht;
366
367 NEIGH_CACHE_STAT_INC(tbl, hash_grows);
368
369 old_nht = rcu_dereference_protected(tbl->nht,
370 lockdep_is_held(&tbl->lock));
371 new_nht = neigh_hash_alloc(new_shift);
372 if (!new_nht)
373 return old_nht;
374
375 for (i = 0; i < (1 << old_nht->hash_shift); i++) {
376 struct neighbour *n, *next;
377
378 for (n = rcu_dereference_protected(old_nht->hash_buckets[i],
379 lockdep_is_held(&tbl->lock));
380 n != NULL;
381 n = next) {
382 hash = tbl->hash(n->primary_key, n->dev,
383 new_nht->hash_rnd);
384
385 hash >>= (32 - new_nht->hash_shift);
386 next = rcu_dereference_protected(n->next,
387 lockdep_is_held(&tbl->lock));
388
389 rcu_assign_pointer(n->next,
390 rcu_dereference_protected(
391 new_nht->hash_buckets[hash],
392 lockdep_is_held(&tbl->lock)));
393 rcu_assign_pointer(new_nht->hash_buckets[hash], n);
394 }
395 }
396
397 rcu_assign_pointer(tbl->nht, new_nht);
398 call_rcu(&old_nht->rcu, neigh_hash_free_rcu);
399 return new_nht;
400}
401
402struct neighbour *neigh_lookup(struct neigh_table *tbl, const void *pkey,
403 struct net_device *dev)
404{
405 struct neighbour *n;
406 int key_len = tbl->key_len;
407 u32 hash_val;
408 struct neigh_hash_table *nht;
409
410 NEIGH_CACHE_STAT_INC(tbl, lookups);
411
412 rcu_read_lock_bh();
413 nht = rcu_dereference_bh(tbl->nht);
414 hash_val = tbl->hash(pkey, dev, nht->hash_rnd) >> (32 - nht->hash_shift);
415
416 for (n = rcu_dereference_bh(nht->hash_buckets[hash_val]);
417 n != NULL;
418 n = rcu_dereference_bh(n->next)) {
419 if (dev == n->dev && !memcmp(n->primary_key, pkey, key_len)) {
420 if (!atomic_inc_not_zero(&n->refcnt))
421 n = NULL;
422 NEIGH_CACHE_STAT_INC(tbl, hits);
423 break;
424 }
425 }
426
427 rcu_read_unlock_bh();
428 return n;
429}
430EXPORT_SYMBOL(neigh_lookup);
431
432struct neighbour *neigh_lookup_nodev(struct neigh_table *tbl, struct net *net,
433 const void *pkey)
434{
435 struct neighbour *n;
436 int key_len = tbl->key_len;
437 u32 hash_val;
438 struct neigh_hash_table *nht;
439
440 NEIGH_CACHE_STAT_INC(tbl, lookups);
441
442 rcu_read_lock_bh();
443 nht = rcu_dereference_bh(tbl->nht);
444 hash_val = tbl->hash(pkey, NULL, nht->hash_rnd) >> (32 - nht->hash_shift);
445
446 for (n = rcu_dereference_bh(nht->hash_buckets[hash_val]);
447 n != NULL;
448 n = rcu_dereference_bh(n->next)) {
449 if (!memcmp(n->primary_key, pkey, key_len) &&
450 net_eq(dev_net(n->dev), net)) {
451 if (!atomic_inc_not_zero(&n->refcnt))
452 n = NULL;
453 NEIGH_CACHE_STAT_INC(tbl, hits);
454 break;
455 }
456 }
457
458 rcu_read_unlock_bh();
459 return n;
460}
461EXPORT_SYMBOL(neigh_lookup_nodev);
462
463struct neighbour *__neigh_create(struct neigh_table *tbl, const void *pkey,
464 struct net_device *dev, bool want_ref)
465{
466 u32 hash_val;
467 int key_len = tbl->key_len;
468 int error;
469 struct neighbour *n1, *rc, *n = neigh_alloc(tbl, dev);
470 struct neigh_hash_table *nht;
471
472 if (!n) {
473 rc = ERR_PTR(-ENOBUFS);
474 goto out;
475 }
476
477 memcpy(n->primary_key, pkey, key_len);
478 n->dev = dev;
479 dev_hold(dev);
480
481 /* Protocol specific setup. */
482 if (tbl->constructor && (error = tbl->constructor(n)) < 0) {
483 rc = ERR_PTR(error);
484 goto out_neigh_release;
485 }
486
487 if (dev->netdev_ops->ndo_neigh_construct) {
488 error = dev->netdev_ops->ndo_neigh_construct(n);
489 if (error < 0) {
490 rc = ERR_PTR(error);
491 goto out_neigh_release;
492 }
493 }
494
495 /* Device specific setup. */
496 if (n->parms->neigh_setup &&
497 (error = n->parms->neigh_setup(n)) < 0) {
498 rc = ERR_PTR(error);
499 goto out_neigh_release;
500 }
501
502 n->confirmed = jiffies - (NEIGH_VAR(n->parms, BASE_REACHABLE_TIME) << 1);
503
504 write_lock_bh(&tbl->lock);
505 nht = rcu_dereference_protected(tbl->nht,
506 lockdep_is_held(&tbl->lock));
507
508 if (atomic_read(&tbl->entries) > (1 << nht->hash_shift))
509 nht = neigh_hash_grow(tbl, nht->hash_shift + 1);
510
511 hash_val = tbl->hash(pkey, dev, nht->hash_rnd) >> (32 - nht->hash_shift);
512
513 if (n->parms->dead) {
514 rc = ERR_PTR(-EINVAL);
515 goto out_tbl_unlock;
516 }
517
518 for (n1 = rcu_dereference_protected(nht->hash_buckets[hash_val],
519 lockdep_is_held(&tbl->lock));
520 n1 != NULL;
521 n1 = rcu_dereference_protected(n1->next,
522 lockdep_is_held(&tbl->lock))) {
523 if (dev == n1->dev && !memcmp(n1->primary_key, pkey, key_len)) {
524 if (want_ref)
525 neigh_hold(n1);
526 rc = n1;
527 goto out_tbl_unlock;
528 }
529 }
530
531 n->dead = 0;
532 if (want_ref)
533 neigh_hold(n);
534 rcu_assign_pointer(n->next,
535 rcu_dereference_protected(nht->hash_buckets[hash_val],
536 lockdep_is_held(&tbl->lock)));
537 rcu_assign_pointer(nht->hash_buckets[hash_val], n);
538 write_unlock_bh(&tbl->lock);
539 neigh_dbg(2, "neigh %p is created\n", n);
540 rc = n;
541out:
542 return rc;
543out_tbl_unlock:
544 write_unlock_bh(&tbl->lock);
545out_neigh_release:
546 neigh_release(n);
547 goto out;
548}
549EXPORT_SYMBOL(__neigh_create);
550
551static u32 pneigh_hash(const void *pkey, int key_len)
552{
553 u32 hash_val = *(u32 *)(pkey + key_len - 4);
554 hash_val ^= (hash_val >> 16);
555 hash_val ^= hash_val >> 8;
556 hash_val ^= hash_val >> 4;
557 hash_val &= PNEIGH_HASHMASK;
558 return hash_val;
559}
560
561static struct pneigh_entry *__pneigh_lookup_1(struct pneigh_entry *n,
562 struct net *net,
563 const void *pkey,
564 int key_len,
565 struct net_device *dev)
566{
567 while (n) {
568 if (!memcmp(n->key, pkey, key_len) &&
569 net_eq(pneigh_net(n), net) &&
570 (n->dev == dev || !n->dev))
571 return n;
572 n = n->next;
573 }
574 return NULL;
575}
576
577struct pneigh_entry *__pneigh_lookup(struct neigh_table *tbl,
578 struct net *net, const void *pkey, struct net_device *dev)
579{
580 int key_len = tbl->key_len;
581 u32 hash_val = pneigh_hash(pkey, key_len);
582
583 return __pneigh_lookup_1(tbl->phash_buckets[hash_val],
584 net, pkey, key_len, dev);
585}
586EXPORT_SYMBOL_GPL(__pneigh_lookup);
587
588struct pneigh_entry * pneigh_lookup(struct neigh_table *tbl,
589 struct net *net, const void *pkey,
590 struct net_device *dev, int creat)
591{
592 struct pneigh_entry *n;
593 int key_len = tbl->key_len;
594 u32 hash_val = pneigh_hash(pkey, key_len);
595
596 read_lock_bh(&tbl->lock);
597 n = __pneigh_lookup_1(tbl->phash_buckets[hash_val],
598 net, pkey, key_len, dev);
599 read_unlock_bh(&tbl->lock);
600
601 if (n || !creat)
602 goto out;
603
604 ASSERT_RTNL();
605
606 n = kmalloc(sizeof(*n) + key_len, GFP_KERNEL);
607 if (!n)
608 goto out;
609
610 write_pnet(&n->net, hold_net(net));
611 memcpy(n->key, pkey, key_len);
612 n->dev = dev;
613 if (dev)
614 dev_hold(dev);
615
616 if (tbl->pconstructor && tbl->pconstructor(n)) {
617 if (dev)
618 dev_put(dev);
619 release_net(net);
620 kfree(n);
621 n = NULL;
622 goto out;
623 }
624
625 write_lock_bh(&tbl->lock);
626 n->next = tbl->phash_buckets[hash_val];
627 tbl->phash_buckets[hash_val] = n;
628 write_unlock_bh(&tbl->lock);
629out:
630 return n;
631}
632EXPORT_SYMBOL(pneigh_lookup);
633
634
635int pneigh_delete(struct neigh_table *tbl, struct net *net, const void *pkey,
636 struct net_device *dev)
637{
638 struct pneigh_entry *n, **np;
639 int key_len = tbl->key_len;
640 u32 hash_val = pneigh_hash(pkey, key_len);
641
642 write_lock_bh(&tbl->lock);
643 for (np = &tbl->phash_buckets[hash_val]; (n = *np) != NULL;
644 np = &n->next) {
645 if (!memcmp(n->key, pkey, key_len) && n->dev == dev &&
646 net_eq(pneigh_net(n), net)) {
647 *np = n->next;
648 write_unlock_bh(&tbl->lock);
649 if (tbl->pdestructor)
650 tbl->pdestructor(n);
651 if (n->dev)
652 dev_put(n->dev);
653 release_net(pneigh_net(n));
654 kfree(n);
655 return 0;
656 }
657 }
658 write_unlock_bh(&tbl->lock);
659 return -ENOENT;
660}
661
662static int pneigh_ifdown(struct neigh_table *tbl, struct net_device *dev)
663{
664 struct pneigh_entry *n, **np;
665 u32 h;
666
667 for (h = 0; h <= PNEIGH_HASHMASK; h++) {
668 np = &tbl->phash_buckets[h];
669 while ((n = *np) != NULL) {
670 if (!dev || n->dev == dev) {
671 *np = n->next;
672 if (tbl->pdestructor)
673 tbl->pdestructor(n);
674 if (n->dev)
675 dev_put(n->dev);
676 release_net(pneigh_net(n));
677 kfree(n);
678 continue;
679 }
680 np = &n->next;
681 }
682 }
683 return -ENOENT;
684}
685
686static void neigh_parms_destroy(struct neigh_parms *parms);
687
688static inline void neigh_parms_put(struct neigh_parms *parms)
689{
690 if (atomic_dec_and_test(&parms->refcnt))
691 neigh_parms_destroy(parms);
692}
693
694/*
695 * neighbour must already be out of the table;
696 *
697 */
698void neigh_destroy(struct neighbour *neigh)
699{
700 struct net_device *dev = neigh->dev;
701
702 NEIGH_CACHE_STAT_INC(neigh->tbl, destroys);
703
704 if (!neigh->dead) {
705 pr_warn("Destroying alive neighbour %p\n", neigh);
706 dump_stack();
707 return;
708 }
709
710 if (neigh_del_timer(neigh))
711 pr_warn("Impossible event\n");
712
713 write_lock_bh(&neigh->lock);
714 __skb_queue_purge(&neigh->arp_queue);
715 write_unlock_bh(&neigh->lock);
716 neigh->arp_queue_len_bytes = 0;
717
718 if (dev->netdev_ops->ndo_neigh_destroy)
719 dev->netdev_ops->ndo_neigh_destroy(neigh);
720
721 dev_put(dev);
722 neigh_parms_put(neigh->parms);
723
724 neigh_dbg(2, "neigh %p is destroyed\n", neigh);
725
726 atomic_dec(&neigh->tbl->entries);
727 kfree_rcu(neigh, rcu);
728}
729EXPORT_SYMBOL(neigh_destroy);
730
731/* Neighbour state is suspicious;
732 disable fast path.
733
734 Called with write_locked neigh.
735 */
736static void neigh_suspect(struct neighbour *neigh)
737{
738 neigh_dbg(2, "neigh %p is suspected\n", neigh);
739
740 neigh->output = neigh->ops->output;
741}
742
743/* Neighbour state is OK;
744 enable fast path.
745
746 Called with write_locked neigh.
747 */
748static void neigh_connect(struct neighbour *neigh)
749{
750 neigh_dbg(2, "neigh %p is connected\n", neigh);
751
752 neigh->output = neigh->ops->connected_output;
753}
754
755static void neigh_periodic_work(struct work_struct *work)
756{
757 struct neigh_table *tbl = container_of(work, struct neigh_table, gc_work.work);
758 struct neighbour *n;
759 struct neighbour __rcu **np;
760 unsigned int i;
761 struct neigh_hash_table *nht;
762
763 NEIGH_CACHE_STAT_INC(tbl, periodic_gc_runs);
764
765 write_lock_bh(&tbl->lock);
766 nht = rcu_dereference_protected(tbl->nht,
767 lockdep_is_held(&tbl->lock));
768
769 /*
770 * periodically recompute ReachableTime from random function
771 */
772
773 if (time_after(jiffies, tbl->last_rand + 300 * HZ)) {
774 struct neigh_parms *p;
775 tbl->last_rand = jiffies;
776 for (p = &tbl->parms; p; p = p->next)
777 p->reachable_time =
778 neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME));
779 }
780
781 if (atomic_read(&tbl->entries) < tbl->gc_thresh1)
782 goto out;
783
784 for (i = 0 ; i < (1 << nht->hash_shift); i++) {
785 np = &nht->hash_buckets[i];
786
787 while ((n = rcu_dereference_protected(*np,
788 lockdep_is_held(&tbl->lock))) != NULL) {
789 unsigned int state;
790
791 write_lock(&n->lock);
792
793 state = n->nud_state;
794 if (state & (NUD_PERMANENT | NUD_IN_TIMER)) {
795 write_unlock(&n->lock);
796 goto next_elt;
797 }
798
799 if (time_before(n->used, n->confirmed))
800 n->used = n->confirmed;
801
802 if (atomic_read(&n->refcnt) == 1 &&
803 (state == NUD_FAILED ||
804 time_after(jiffies, n->used + NEIGH_VAR(n->parms, GC_STALETIME)))) {
805 *np = n->next;
806 n->dead = 1;
807 write_unlock(&n->lock);
808 neigh_cleanup_and_release(n);
809 continue;
810 }
811 write_unlock(&n->lock);
812
813next_elt:
814 np = &n->next;
815 }
816 /*
817 * It's fine to release lock here, even if hash table
818 * grows while we are preempted.
819 */
820 write_unlock_bh(&tbl->lock);
821 cond_resched();
822 write_lock_bh(&tbl->lock);
823 nht = rcu_dereference_protected(tbl->nht,
824 lockdep_is_held(&tbl->lock));
825 }
826out:
827 /* Cycle through all hash buckets every BASE_REACHABLE_TIME/2 ticks.
828 * ARP entry timeouts range from 1/2 BASE_REACHABLE_TIME to 3/2
829 * BASE_REACHABLE_TIME.
830 */
831 queue_delayed_work(system_power_efficient_wq, &tbl->gc_work,
832 NEIGH_VAR(&tbl->parms, BASE_REACHABLE_TIME) >> 1);
833 write_unlock_bh(&tbl->lock);
834}
835
836static __inline__ int neigh_max_probes(struct neighbour *n)
837{
838 struct neigh_parms *p = n->parms;
839 int max_probes = NEIGH_VAR(p, UCAST_PROBES) + NEIGH_VAR(p, APP_PROBES);
840 if (!(n->nud_state & NUD_PROBE))
841 max_probes += NEIGH_VAR(p, MCAST_PROBES);
842 return max_probes;
843}
844
845static void neigh_invalidate(struct neighbour *neigh)
846 __releases(neigh->lock)
847 __acquires(neigh->lock)
848{
849 struct sk_buff *skb;
850
851 NEIGH_CACHE_STAT_INC(neigh->tbl, res_failed);
852 neigh_dbg(2, "neigh %p is failed\n", neigh);
853 neigh->updated = jiffies;
854
855 /* It is very thin place. report_unreachable is very complicated
856 routine. Particularly, it can hit the same neighbour entry!
857
858 So that, we try to be accurate and avoid dead loop. --ANK
859 */
860 while (neigh->nud_state == NUD_FAILED &&
861 (skb = __skb_dequeue(&neigh->arp_queue)) != NULL) {
862 write_unlock(&neigh->lock);
863 neigh->ops->error_report(neigh, skb);
864 write_lock(&neigh->lock);
865 }
866 __skb_queue_purge(&neigh->arp_queue);
867 neigh->arp_queue_len_bytes = 0;
868}
869
870static void neigh_probe(struct neighbour *neigh)
871 __releases(neigh->lock)
872{
873 struct sk_buff *skb = skb_peek_tail(&neigh->arp_queue);
874 /* keep skb alive even if arp_queue overflows */
875 if (skb)
876 skb = skb_copy(skb, GFP_ATOMIC);
877 write_unlock(&neigh->lock);
878 neigh->ops->solicit(neigh, skb);
879 atomic_inc(&neigh->probes);
880 kfree_skb(skb);
881}
882
883/* Called when a timer expires for a neighbour entry. */
884
885static void neigh_timer_handler(unsigned long arg)
886{
887 unsigned long now, next;
888 struct neighbour *neigh = (struct neighbour *)arg;
889 unsigned int state;
890 int notify = 0;
891
892 write_lock(&neigh->lock);
893
894 state = neigh->nud_state;
895 now = jiffies;
896 next = now + HZ;
897
898 if (!(state & NUD_IN_TIMER))
899 goto out;
900
901 if (state & NUD_REACHABLE) {
902 if (time_before_eq(now,
903 neigh->confirmed + neigh->parms->reachable_time)) {
904 neigh_dbg(2, "neigh %p is still alive\n", neigh);
905 next = neigh->confirmed + neigh->parms->reachable_time;
906 } else if (time_before_eq(now,
907 neigh->used +
908 NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME))) {
909 neigh_dbg(2, "neigh %p is delayed\n", neigh);
910 neigh->nud_state = NUD_DELAY;
911 neigh->updated = jiffies;
912 neigh_suspect(neigh);
913 next = now + NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME);
914 } else {
915 neigh_dbg(2, "neigh %p is suspected\n", neigh);
916 neigh->nud_state = NUD_STALE;
917 neigh->updated = jiffies;
918 neigh_suspect(neigh);
919 notify = 1;
920 }
921 } else if (state & NUD_DELAY) {
922 if (time_before_eq(now,
923 neigh->confirmed +
924 NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME))) {
925 neigh_dbg(2, "neigh %p is now reachable\n", neigh);
926 neigh->nud_state = NUD_REACHABLE;
927 neigh->updated = jiffies;
928 neigh_connect(neigh);
929 notify = 1;
930 next = neigh->confirmed + neigh->parms->reachable_time;
931 } else {
932 neigh_dbg(2, "neigh %p is probed\n", neigh);
933 neigh->nud_state = NUD_PROBE;
934 neigh->updated = jiffies;
935 atomic_set(&neigh->probes, 0);
936 next = now + NEIGH_VAR(neigh->parms, RETRANS_TIME);
937 }
938 } else {
939 /* NUD_PROBE|NUD_INCOMPLETE */
940 next = now + NEIGH_VAR(neigh->parms, RETRANS_TIME);
941 }
942
943 if ((neigh->nud_state & (NUD_INCOMPLETE | NUD_PROBE)) &&
944 atomic_read(&neigh->probes) >= neigh_max_probes(neigh)) {
945 neigh->nud_state = NUD_FAILED;
946 notify = 1;
947 neigh_invalidate(neigh);
948 goto out;
949 }
950
951 if (neigh->nud_state & NUD_IN_TIMER) {
952 if (time_before(next, jiffies + HZ/2))
953 next = jiffies + HZ/2;
954 if (!mod_timer(&neigh->timer, next))
955 neigh_hold(neigh);
956 }
957 if (neigh->nud_state & (NUD_INCOMPLETE | NUD_PROBE)) {
958 neigh_probe(neigh);
959 } else {
960out:
961 write_unlock(&neigh->lock);
962 }
963
964 if (notify)
965 neigh_update_notify(neigh);
966
967 neigh_release(neigh);
968}
969
970int __neigh_event_send(struct neighbour *neigh, struct sk_buff *skb)
971{
972 int rc;
973 bool immediate_probe = false;
974
975 write_lock_bh(&neigh->lock);
976
977 rc = 0;
978 if (neigh->nud_state & (NUD_CONNECTED | NUD_DELAY | NUD_PROBE))
979 goto out_unlock_bh;
980
981 if (!(neigh->nud_state & (NUD_STALE | NUD_INCOMPLETE))) {
982 if (NEIGH_VAR(neigh->parms, MCAST_PROBES) +
983 NEIGH_VAR(neigh->parms, APP_PROBES)) {
984 unsigned long next, now = jiffies;
985
986 atomic_set(&neigh->probes,
987 NEIGH_VAR(neigh->parms, UCAST_PROBES));
988 neigh->nud_state = NUD_INCOMPLETE;
989 neigh->updated = now;
990 next = now + max(NEIGH_VAR(neigh->parms, RETRANS_TIME),
991 HZ/2);
992 neigh_add_timer(neigh, next);
993 immediate_probe = true;
994 } else {
995 neigh->nud_state = NUD_FAILED;
996 neigh->updated = jiffies;
997 write_unlock_bh(&neigh->lock);
998
999 kfree_skb(skb);
1000 return 1;
1001 }
1002 } else if (neigh->nud_state & NUD_STALE) {
1003 neigh_dbg(2, "neigh %p is delayed\n", neigh);
1004 neigh->nud_state = NUD_DELAY;
1005 neigh->updated = jiffies;
1006 neigh_add_timer(neigh, jiffies +
1007 NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME));
1008 }
1009
1010 if (neigh->nud_state == NUD_INCOMPLETE) {
1011 if (skb) {
1012 while (neigh->arp_queue_len_bytes + skb->truesize >
1013 NEIGH_VAR(neigh->parms, QUEUE_LEN_BYTES)) {
1014 struct sk_buff *buff;
1015
1016 buff = __skb_dequeue(&neigh->arp_queue);
1017 if (!buff)
1018 break;
1019 neigh->arp_queue_len_bytes -= buff->truesize;
1020 kfree_skb(buff);
1021 NEIGH_CACHE_STAT_INC(neigh->tbl, unres_discards);
1022 }
1023 skb_dst_force(skb);
1024 __skb_queue_tail(&neigh->arp_queue, skb);
1025 neigh->arp_queue_len_bytes += skb->truesize;
1026 }
1027 rc = 1;
1028 }
1029out_unlock_bh:
1030 if (immediate_probe)
1031 neigh_probe(neigh);
1032 else
1033 write_unlock(&neigh->lock);
1034 local_bh_enable();
1035 return rc;
1036}
1037EXPORT_SYMBOL(__neigh_event_send);
1038
1039static void neigh_update_hhs(struct neighbour *neigh)
1040{
1041 struct hh_cache *hh;
1042 void (*update)(struct hh_cache*, const struct net_device*, const unsigned char *)
1043 = NULL;
1044
1045 if (neigh->dev->header_ops)
1046 update = neigh->dev->header_ops->cache_update;
1047
1048 if (update) {
1049 hh = &neigh->hh;
1050 if (hh->hh_len) {
1051 write_seqlock_bh(&hh->hh_lock);
1052 update(hh, neigh->dev, neigh->ha);
1053 write_sequnlock_bh(&hh->hh_lock);
1054 }
1055 }
1056}
1057
1058
1059
1060/* Generic update routine.
1061 -- lladdr is new lladdr or NULL, if it is not supplied.
1062 -- new is new state.
1063 -- flags
1064 NEIGH_UPDATE_F_OVERRIDE allows to override existing lladdr,
1065 if it is different.
1066 NEIGH_UPDATE_F_WEAK_OVERRIDE will suspect existing "connected"
1067 lladdr instead of overriding it
1068 if it is different.
1069 It also allows to retain current state
1070 if lladdr is unchanged.
1071 NEIGH_UPDATE_F_ADMIN means that the change is administrative.
1072
1073 NEIGH_UPDATE_F_OVERRIDE_ISROUTER allows to override existing
1074 NTF_ROUTER flag.
1075 NEIGH_UPDATE_F_ISROUTER indicates if the neighbour is known as
1076 a router.
1077
1078 Caller MUST hold reference count on the entry.
1079 */
1080
1081int neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new,
1082 u32 flags)
1083{
1084 u8 old;
1085 int err;
1086 int notify = 0;
1087 struct net_device *dev;
1088 int update_isrouter = 0;
1089
1090 write_lock_bh(&neigh->lock);
1091
1092 dev = neigh->dev;
1093 old = neigh->nud_state;
1094 err = -EPERM;
1095
1096 if (!(flags & NEIGH_UPDATE_F_ADMIN) &&
1097 (old & (NUD_NOARP | NUD_PERMANENT)))
1098 goto out;
1099
1100 if (!(new & NUD_VALID)) {
1101 neigh_del_timer(neigh);
1102 if (old & NUD_CONNECTED)
1103 neigh_suspect(neigh);
1104 neigh->nud_state = new;
1105 err = 0;
1106 notify = old & NUD_VALID;
1107 if ((old & (NUD_INCOMPLETE | NUD_PROBE)) &&
1108 (new & NUD_FAILED)) {
1109 neigh_invalidate(neigh);
1110 notify = 1;
1111 }
1112 goto out;
1113 }
1114
1115 /* Compare new lladdr with cached one */
1116 if (!dev->addr_len) {
1117 /* First case: device needs no address. */
1118 lladdr = neigh->ha;
1119 } else if (lladdr) {
1120 /* The second case: if something is already cached
1121 and a new address is proposed:
1122 - compare new & old
1123 - if they are different, check override flag
1124 */
1125 if ((old & NUD_VALID) &&
1126 !memcmp(lladdr, neigh->ha, dev->addr_len))
1127 lladdr = neigh->ha;
1128 } else {
1129 /* No address is supplied; if we know something,
1130 use it, otherwise discard the request.
1131 */
1132 err = -EINVAL;
1133 if (!(old & NUD_VALID))
1134 goto out;
1135 lladdr = neigh->ha;
1136 }
1137
1138 if (new & NUD_CONNECTED)
1139 neigh->confirmed = jiffies;
1140 neigh->updated = jiffies;
1141
1142 /* If entry was valid and address is not changed,
1143 do not change entry state, if new one is STALE.
1144 */
1145 err = 0;
1146 update_isrouter = flags & NEIGH_UPDATE_F_OVERRIDE_ISROUTER;
1147 if (old & NUD_VALID) {
1148 if (lladdr != neigh->ha && !(flags & NEIGH_UPDATE_F_OVERRIDE)) {
1149 update_isrouter = 0;
1150 if ((flags & NEIGH_UPDATE_F_WEAK_OVERRIDE) &&
1151 (old & NUD_CONNECTED)) {
1152 lladdr = neigh->ha;
1153 new = NUD_STALE;
1154 } else
1155 goto out;
1156 } else {
1157 if (lladdr == neigh->ha && new == NUD_STALE &&
1158 ((flags & NEIGH_UPDATE_F_WEAK_OVERRIDE) ||
1159 (old & NUD_CONNECTED))
1160 )
1161 new = old;
1162 }
1163 }
1164
1165 if (new != old) {
1166 neigh_del_timer(neigh);
1167 if (new & NUD_IN_TIMER)
1168 neigh_add_timer(neigh, (jiffies +
1169 ((new & NUD_REACHABLE) ?
1170 neigh->parms->reachable_time :
1171 0)));
1172 neigh->nud_state = new;
1173 notify = 1;
1174 }
1175
1176 if (lladdr != neigh->ha) {
1177 write_seqlock(&neigh->ha_lock);
1178 memcpy(&neigh->ha, lladdr, dev->addr_len);
1179 write_sequnlock(&neigh->ha_lock);
1180 neigh_update_hhs(neigh);
1181 if (!(new & NUD_CONNECTED))
1182 neigh->confirmed = jiffies -
1183 (NEIGH_VAR(neigh->parms, BASE_REACHABLE_TIME) << 1);
1184 notify = 1;
1185 }
1186 if (new == old)
1187 goto out;
1188 if (new & NUD_CONNECTED)
1189 neigh_connect(neigh);
1190 else
1191 neigh_suspect(neigh);
1192 if (!(old & NUD_VALID)) {
1193 struct sk_buff *skb;
1194
1195 /* Again: avoid dead loop if something went wrong */
1196
1197 while (neigh->nud_state & NUD_VALID &&
1198 (skb = __skb_dequeue(&neigh->arp_queue)) != NULL) {
1199 struct dst_entry *dst = skb_dst(skb);
1200 struct neighbour *n2, *n1 = neigh;
1201 write_unlock_bh(&neigh->lock);
1202
1203 rcu_read_lock();
1204
1205 /* Why not just use 'neigh' as-is? The problem is that
1206 * things such as shaper, eql, and sch_teql can end up
1207 * using alternative, different, neigh objects to output
1208 * the packet in the output path. So what we need to do
1209 * here is re-lookup the top-level neigh in the path so
1210 * we can reinject the packet there.
1211 */
1212 n2 = NULL;
1213 if (dst) {
1214 n2 = dst_neigh_lookup_skb(dst, skb);
1215 if (n2)
1216 n1 = n2;
1217 }
1218 n1->output(n1, skb);
1219 if (n2)
1220 neigh_release(n2);
1221 rcu_read_unlock();
1222
1223 write_lock_bh(&neigh->lock);
1224 }
1225 __skb_queue_purge(&neigh->arp_queue);
1226 neigh->arp_queue_len_bytes = 0;
1227 }
1228out:
1229 if (update_isrouter) {
1230 neigh->flags = (flags & NEIGH_UPDATE_F_ISROUTER) ?
1231 (neigh->flags | NTF_ROUTER) :
1232 (neigh->flags & ~NTF_ROUTER);
1233 }
1234 write_unlock_bh(&neigh->lock);
1235
1236 if (notify)
1237 neigh_update_notify(neigh);
1238
1239 return err;
1240}
1241EXPORT_SYMBOL(neigh_update);
1242
1243/* Update the neigh to listen temporarily for probe responses, even if it is
1244 * in a NUD_FAILED state. The caller has to hold neigh->lock for writing.
1245 */
1246void __neigh_set_probe_once(struct neighbour *neigh)
1247{
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, struct dst_entry *dst)
1273{
1274 struct net_device *dev = dst->dev;
1275 __be16 prot = dst->ops->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/* This function can be used in contexts, where only old dev_queue_xmit
1290 * worked, f.e. if you want to override normal output path (eql, shaper),
1291 * but resolution is not made yet.
1292 */
1293
1294int neigh_compat_output(struct neighbour *neigh, struct sk_buff *skb)
1295{
1296 struct net_device *dev = skb->dev;
1297
1298 __skb_pull(skb, skb_network_offset(skb));
1299
1300 if (dev_hard_header(skb, dev, ntohs(skb->protocol), NULL, NULL,
1301 skb->len) < 0 &&
1302 dev_rebuild_header(skb))
1303 return 0;
1304
1305 return dev_queue_xmit(skb);
1306}
1307EXPORT_SYMBOL(neigh_compat_output);
1308
1309/* Slow and careful. */
1310
1311int neigh_resolve_output(struct neighbour *neigh, struct sk_buff *skb)
1312{
1313 struct dst_entry *dst = skb_dst(skb);
1314 int rc = 0;
1315
1316 if (!dst)
1317 goto discard;
1318
1319 if (!neigh_event_send(neigh, skb)) {
1320 int err;
1321 struct net_device *dev = neigh->dev;
1322 unsigned int seq;
1323
1324 if (dev->header_ops->cache && !neigh->hh.hh_len)
1325 neigh_hh_init(neigh, dst);
1326
1327 do {
1328 __skb_pull(skb, skb_network_offset(skb));
1329 seq = read_seqbegin(&neigh->ha_lock);
1330 err = dev_hard_header(skb, dev, ntohs(skb->protocol),
1331 neigh->ha, NULL, skb->len);
1332 } while (read_seqretry(&neigh->ha_lock, seq));
1333
1334 if (err >= 0)
1335 rc = dev_queue_xmit(skb);
1336 else
1337 goto out_kfree_skb;
1338 }
1339out:
1340 return rc;
1341discard:
1342 neigh_dbg(1, "%s: dst=%p neigh=%p\n", __func__, dst, neigh);
1343out_kfree_skb:
1344 rc = -EINVAL;
1345 kfree_skb(skb);
1346 goto out;
1347}
1348EXPORT_SYMBOL(neigh_resolve_output);
1349
1350/* As fast as possible without hh cache */
1351
1352int neigh_connected_output(struct neighbour *neigh, struct sk_buff *skb)
1353{
1354 struct net_device *dev = neigh->dev;
1355 unsigned int seq;
1356 int err;
1357
1358 do {
1359 __skb_pull(skb, skb_network_offset(skb));
1360 seq = read_seqbegin(&neigh->ha_lock);
1361 err = dev_hard_header(skb, dev, ntohs(skb->protocol),
1362 neigh->ha, NULL, skb->len);
1363 } while (read_seqretry(&neigh->ha_lock, seq));
1364
1365 if (err >= 0)
1366 err = dev_queue_xmit(skb);
1367 else {
1368 err = -EINVAL;
1369 kfree_skb(skb);
1370 }
1371 return err;
1372}
1373EXPORT_SYMBOL(neigh_connected_output);
1374
1375int neigh_direct_output(struct neighbour *neigh, struct sk_buff *skb)
1376{
1377 return dev_queue_xmit(skb);
1378}
1379EXPORT_SYMBOL(neigh_direct_output);
1380
1381static void neigh_proxy_process(unsigned long arg)
1382{
1383 struct neigh_table *tbl = (struct neigh_table *)arg;
1384 long sched_next = 0;
1385 unsigned long now = jiffies;
1386 struct sk_buff *skb, *n;
1387
1388 spin_lock(&tbl->proxy_queue.lock);
1389
1390 skb_queue_walk_safe(&tbl->proxy_queue, skb, n) {
1391 long tdif = NEIGH_CB(skb)->sched_next - now;
1392
1393 if (tdif <= 0) {
1394 struct net_device *dev = skb->dev;
1395
1396 __skb_unlink(skb, &tbl->proxy_queue);
1397 if (tbl->proxy_redo && netif_running(dev)) {
1398 rcu_read_lock();
1399 tbl->proxy_redo(skb);
1400 rcu_read_unlock();
1401 } else {
1402 kfree_skb(skb);
1403 }
1404
1405 dev_put(dev);
1406 } else if (!sched_next || tdif < sched_next)
1407 sched_next = tdif;
1408 }
1409 del_timer(&tbl->proxy_timer);
1410 if (sched_next)
1411 mod_timer(&tbl->proxy_timer, jiffies + sched_next);
1412 spin_unlock(&tbl->proxy_queue.lock);
1413}
1414
1415void pneigh_enqueue(struct neigh_table *tbl, struct neigh_parms *p,
1416 struct sk_buff *skb)
1417{
1418 unsigned long now = jiffies;
1419
1420 unsigned long sched_next = now + (prandom_u32() %
1421 NEIGH_VAR(p, PROXY_DELAY));
1422
1423 if (tbl->proxy_queue.qlen > NEIGH_VAR(p, PROXY_QLEN)) {
1424 kfree_skb(skb);
1425 return;
1426 }
1427
1428 NEIGH_CB(skb)->sched_next = sched_next;
1429 NEIGH_CB(skb)->flags |= LOCALLY_ENQUEUED;
1430
1431 spin_lock(&tbl->proxy_queue.lock);
1432 if (del_timer(&tbl->proxy_timer)) {
1433 if (time_before(tbl->proxy_timer.expires, sched_next))
1434 sched_next = tbl->proxy_timer.expires;
1435 }
1436 skb_dst_drop(skb);
1437 dev_hold(skb->dev);
1438 __skb_queue_tail(&tbl->proxy_queue, skb);
1439 mod_timer(&tbl->proxy_timer, sched_next);
1440 spin_unlock(&tbl->proxy_queue.lock);
1441}
1442EXPORT_SYMBOL(pneigh_enqueue);
1443
1444static inline struct neigh_parms *lookup_neigh_parms(struct neigh_table *tbl,
1445 struct net *net, int ifindex)
1446{
1447 struct neigh_parms *p;
1448
1449 for (p = &tbl->parms; p; p = p->next) {
1450 if ((p->dev && p->dev->ifindex == ifindex && net_eq(neigh_parms_net(p), net)) ||
1451 (!p->dev && !ifindex && net_eq(net, &init_net)))
1452 return p;
1453 }
1454
1455 return NULL;
1456}
1457
1458struct neigh_parms *neigh_parms_alloc(struct net_device *dev,
1459 struct neigh_table *tbl)
1460{
1461 struct neigh_parms *p;
1462 struct net *net = dev_net(dev);
1463 const struct net_device_ops *ops = dev->netdev_ops;
1464
1465 p = kmemdup(&tbl->parms, sizeof(*p), GFP_KERNEL);
1466 if (p) {
1467 p->tbl = tbl;
1468 atomic_set(&p->refcnt, 1);
1469 p->reachable_time =
1470 neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME));
1471 dev_hold(dev);
1472 p->dev = dev;
1473 write_pnet(&p->net, hold_net(net));
1474 p->sysctl_table = NULL;
1475
1476 if (ops->ndo_neigh_setup && ops->ndo_neigh_setup(dev, p)) {
1477 release_net(net);
1478 dev_put(dev);
1479 kfree(p);
1480 return NULL;
1481 }
1482
1483 write_lock_bh(&tbl->lock);
1484 p->next = tbl->parms.next;
1485 tbl->parms.next = p;
1486 write_unlock_bh(&tbl->lock);
1487
1488 neigh_parms_data_state_cleanall(p);
1489 }
1490 return p;
1491}
1492EXPORT_SYMBOL(neigh_parms_alloc);
1493
1494static void neigh_rcu_free_parms(struct rcu_head *head)
1495{
1496 struct neigh_parms *parms =
1497 container_of(head, struct neigh_parms, rcu_head);
1498
1499 neigh_parms_put(parms);
1500}
1501
1502void neigh_parms_release(struct neigh_table *tbl, struct neigh_parms *parms)
1503{
1504 struct neigh_parms **p;
1505
1506 if (!parms || parms == &tbl->parms)
1507 return;
1508 write_lock_bh(&tbl->lock);
1509 for (p = &tbl->parms.next; *p; p = &(*p)->next) {
1510 if (*p == parms) {
1511 *p = parms->next;
1512 parms->dead = 1;
1513 write_unlock_bh(&tbl->lock);
1514 if (parms->dev)
1515 dev_put(parms->dev);
1516 call_rcu(&parms->rcu_head, neigh_rcu_free_parms);
1517 return;
1518 }
1519 }
1520 write_unlock_bh(&tbl->lock);
1521 neigh_dbg(1, "%s: not found\n", __func__);
1522}
1523EXPORT_SYMBOL(neigh_parms_release);
1524
1525static void neigh_parms_destroy(struct neigh_parms *parms)
1526{
1527 release_net(neigh_parms_net(parms));
1528 kfree(parms);
1529}
1530
1531static struct lock_class_key neigh_table_proxy_queue_class;
1532
1533static void neigh_table_init_no_netlink(struct neigh_table *tbl)
1534{
1535 unsigned long now = jiffies;
1536 unsigned long phsize;
1537
1538 write_pnet(&tbl->parms.net, &init_net);
1539 atomic_set(&tbl->parms.refcnt, 1);
1540 tbl->parms.reachable_time =
1541 neigh_rand_reach_time(NEIGH_VAR(&tbl->parms, BASE_REACHABLE_TIME));
1542
1543 tbl->stats = alloc_percpu(struct neigh_statistics);
1544 if (!tbl->stats)
1545 panic("cannot create neighbour cache statistics");
1546
1547#ifdef CONFIG_PROC_FS
1548 if (!proc_create_data(tbl->id, 0, init_net.proc_net_stat,
1549 &neigh_stat_seq_fops, tbl))
1550 panic("cannot create neighbour proc dir entry");
1551#endif
1552
1553 RCU_INIT_POINTER(tbl->nht, neigh_hash_alloc(3));
1554
1555 phsize = (PNEIGH_HASHMASK + 1) * sizeof(struct pneigh_entry *);
1556 tbl->phash_buckets = kzalloc(phsize, GFP_KERNEL);
1557
1558 if (!tbl->nht || !tbl->phash_buckets)
1559 panic("cannot allocate neighbour cache hashes");
1560
1561 if (!tbl->entry_size)
1562 tbl->entry_size = ALIGN(offsetof(struct neighbour, primary_key) +
1563 tbl->key_len, NEIGH_PRIV_ALIGN);
1564 else
1565 WARN_ON(tbl->entry_size % NEIGH_PRIV_ALIGN);
1566
1567 rwlock_init(&tbl->lock);
1568 INIT_DEFERRABLE_WORK(&tbl->gc_work, neigh_periodic_work);
1569 queue_delayed_work(system_power_efficient_wq, &tbl->gc_work,
1570 tbl->parms.reachable_time);
1571 setup_timer(&tbl->proxy_timer, neigh_proxy_process, (unsigned long)tbl);
1572 skb_queue_head_init_class(&tbl->proxy_queue,
1573 &neigh_table_proxy_queue_class);
1574
1575 tbl->last_flush = now;
1576 tbl->last_rand = now + tbl->parms.reachable_time * 20;
1577}
1578
1579void neigh_table_init(struct neigh_table *tbl)
1580{
1581 struct neigh_table *tmp;
1582
1583 neigh_table_init_no_netlink(tbl);
1584 write_lock(&neigh_tbl_lock);
1585 for (tmp = neigh_tables; tmp; tmp = tmp->next) {
1586 if (tmp->family == tbl->family)
1587 break;
1588 }
1589 tbl->next = neigh_tables;
1590 neigh_tables = tbl;
1591 write_unlock(&neigh_tbl_lock);
1592
1593 if (unlikely(tmp)) {
1594 pr_err("Registering multiple tables for family %d\n",
1595 tbl->family);
1596 dump_stack();
1597 }
1598}
1599EXPORT_SYMBOL(neigh_table_init);
1600
1601int neigh_table_clear(struct neigh_table *tbl)
1602{
1603 struct neigh_table **tp;
1604
1605 /* It is not clean... Fix it to unload IPv6 module safely */
1606 cancel_delayed_work_sync(&tbl->gc_work);
1607 del_timer_sync(&tbl->proxy_timer);
1608 pneigh_queue_purge(&tbl->proxy_queue);
1609 neigh_ifdown(tbl, NULL);
1610 if (atomic_read(&tbl->entries))
1611 pr_crit("neighbour leakage\n");
1612 write_lock(&neigh_tbl_lock);
1613 for (tp = &neigh_tables; *tp; tp = &(*tp)->next) {
1614 if (*tp == tbl) {
1615 *tp = tbl->next;
1616 break;
1617 }
1618 }
1619 write_unlock(&neigh_tbl_lock);
1620
1621 call_rcu(&rcu_dereference_protected(tbl->nht, 1)->rcu,
1622 neigh_hash_free_rcu);
1623 tbl->nht = NULL;
1624
1625 kfree(tbl->phash_buckets);
1626 tbl->phash_buckets = NULL;
1627
1628 remove_proc_entry(tbl->id, init_net.proc_net_stat);
1629
1630 free_percpu(tbl->stats);
1631 tbl->stats = NULL;
1632
1633 return 0;
1634}
1635EXPORT_SYMBOL(neigh_table_clear);
1636
1637static int neigh_delete(struct sk_buff *skb, struct nlmsghdr *nlh)
1638{
1639 struct net *net = sock_net(skb->sk);
1640 struct ndmsg *ndm;
1641 struct nlattr *dst_attr;
1642 struct neigh_table *tbl;
1643 struct net_device *dev = NULL;
1644 int err = -EINVAL;
1645
1646 ASSERT_RTNL();
1647 if (nlmsg_len(nlh) < sizeof(*ndm))
1648 goto out;
1649
1650 dst_attr = nlmsg_find_attr(nlh, sizeof(*ndm), NDA_DST);
1651 if (dst_attr == NULL)
1652 goto out;
1653
1654 ndm = nlmsg_data(nlh);
1655 if (ndm->ndm_ifindex) {
1656 dev = __dev_get_by_index(net, ndm->ndm_ifindex);
1657 if (dev == NULL) {
1658 err = -ENODEV;
1659 goto out;
1660 }
1661 }
1662
1663 read_lock(&neigh_tbl_lock);
1664 for (tbl = neigh_tables; tbl; tbl = tbl->next) {
1665 struct neighbour *neigh;
1666
1667 if (tbl->family != ndm->ndm_family)
1668 continue;
1669 read_unlock(&neigh_tbl_lock);
1670
1671 if (nla_len(dst_attr) < tbl->key_len)
1672 goto out;
1673
1674 if (ndm->ndm_flags & NTF_PROXY) {
1675 err = pneigh_delete(tbl, net, nla_data(dst_attr), dev);
1676 goto out;
1677 }
1678
1679 if (dev == NULL)
1680 goto out;
1681
1682 neigh = neigh_lookup(tbl, nla_data(dst_attr), dev);
1683 if (neigh == NULL) {
1684 err = -ENOENT;
1685 goto out;
1686 }
1687
1688 err = neigh_update(neigh, NULL, NUD_FAILED,
1689 NEIGH_UPDATE_F_OVERRIDE |
1690 NEIGH_UPDATE_F_ADMIN);
1691 neigh_release(neigh);
1692 goto out;
1693 }
1694 read_unlock(&neigh_tbl_lock);
1695 err = -EAFNOSUPPORT;
1696
1697out:
1698 return err;
1699}
1700
1701static int neigh_add(struct sk_buff *skb, struct nlmsghdr *nlh)
1702{
1703 struct net *net = sock_net(skb->sk);
1704 struct ndmsg *ndm;
1705 struct nlattr *tb[NDA_MAX+1];
1706 struct neigh_table *tbl;
1707 struct net_device *dev = NULL;
1708 int err;
1709
1710 ASSERT_RTNL();
1711 err = nlmsg_parse(nlh, sizeof(*ndm), tb, NDA_MAX, NULL);
1712 if (err < 0)
1713 goto out;
1714
1715 err = -EINVAL;
1716 if (tb[NDA_DST] == NULL)
1717 goto out;
1718
1719 ndm = nlmsg_data(nlh);
1720 if (ndm->ndm_ifindex) {
1721 dev = __dev_get_by_index(net, ndm->ndm_ifindex);
1722 if (dev == NULL) {
1723 err = -ENODEV;
1724 goto out;
1725 }
1726
1727 if (tb[NDA_LLADDR] && nla_len(tb[NDA_LLADDR]) < dev->addr_len)
1728 goto out;
1729 }
1730
1731 read_lock(&neigh_tbl_lock);
1732 for (tbl = neigh_tables; tbl; tbl = tbl->next) {
1733 int flags = NEIGH_UPDATE_F_ADMIN | NEIGH_UPDATE_F_OVERRIDE;
1734 struct neighbour *neigh;
1735 void *dst, *lladdr;
1736
1737 if (tbl->family != ndm->ndm_family)
1738 continue;
1739 read_unlock(&neigh_tbl_lock);
1740
1741 if (nla_len(tb[NDA_DST]) < tbl->key_len)
1742 goto out;
1743 dst = nla_data(tb[NDA_DST]);
1744 lladdr = tb[NDA_LLADDR] ? nla_data(tb[NDA_LLADDR]) : NULL;
1745
1746 if (ndm->ndm_flags & NTF_PROXY) {
1747 struct pneigh_entry *pn;
1748
1749 err = -ENOBUFS;
1750 pn = pneigh_lookup(tbl, net, dst, dev, 1);
1751 if (pn) {
1752 pn->flags = ndm->ndm_flags;
1753 err = 0;
1754 }
1755 goto out;
1756 }
1757
1758 if (dev == NULL)
1759 goto out;
1760
1761 neigh = neigh_lookup(tbl, dst, dev);
1762 if (neigh == NULL) {
1763 if (!(nlh->nlmsg_flags & NLM_F_CREATE)) {
1764 err = -ENOENT;
1765 goto out;
1766 }
1767
1768 neigh = __neigh_lookup_errno(tbl, dst, dev);
1769 if (IS_ERR(neigh)) {
1770 err = PTR_ERR(neigh);
1771 goto out;
1772 }
1773 } else {
1774 if (nlh->nlmsg_flags & NLM_F_EXCL) {
1775 err = -EEXIST;
1776 neigh_release(neigh);
1777 goto out;
1778 }
1779
1780 if (!(nlh->nlmsg_flags & NLM_F_REPLACE))
1781 flags &= ~NEIGH_UPDATE_F_OVERRIDE;
1782 }
1783
1784 if (ndm->ndm_flags & NTF_USE) {
1785 neigh_event_send(neigh, NULL);
1786 err = 0;
1787 } else
1788 err = neigh_update(neigh, lladdr, ndm->ndm_state, flags);
1789 neigh_release(neigh);
1790 goto out;
1791 }
1792
1793 read_unlock(&neigh_tbl_lock);
1794 err = -EAFNOSUPPORT;
1795out:
1796 return err;
1797}
1798
1799static int neightbl_fill_parms(struct sk_buff *skb, struct neigh_parms *parms)
1800{
1801 struct nlattr *nest;
1802
1803 nest = nla_nest_start(skb, NDTA_PARMS);
1804 if (nest == NULL)
1805 return -ENOBUFS;
1806
1807 if ((parms->dev &&
1808 nla_put_u32(skb, NDTPA_IFINDEX, parms->dev->ifindex)) ||
1809 nla_put_u32(skb, NDTPA_REFCNT, atomic_read(&parms->refcnt)) ||
1810 nla_put_u32(skb, NDTPA_QUEUE_LENBYTES,
1811 NEIGH_VAR(parms, QUEUE_LEN_BYTES)) ||
1812 /* approximative value for deprecated QUEUE_LEN (in packets) */
1813 nla_put_u32(skb, NDTPA_QUEUE_LEN,
1814 NEIGH_VAR(parms, QUEUE_LEN_BYTES) / SKB_TRUESIZE(ETH_FRAME_LEN)) ||
1815 nla_put_u32(skb, NDTPA_PROXY_QLEN, NEIGH_VAR(parms, PROXY_QLEN)) ||
1816 nla_put_u32(skb, NDTPA_APP_PROBES, NEIGH_VAR(parms, APP_PROBES)) ||
1817 nla_put_u32(skb, NDTPA_UCAST_PROBES,
1818 NEIGH_VAR(parms, UCAST_PROBES)) ||
1819 nla_put_u32(skb, NDTPA_MCAST_PROBES,
1820 NEIGH_VAR(parms, MCAST_PROBES)) ||
1821 nla_put_msecs(skb, NDTPA_REACHABLE_TIME, parms->reachable_time) ||
1822 nla_put_msecs(skb, NDTPA_BASE_REACHABLE_TIME,
1823 NEIGH_VAR(parms, BASE_REACHABLE_TIME)) ||
1824 nla_put_msecs(skb, NDTPA_GC_STALETIME,
1825 NEIGH_VAR(parms, GC_STALETIME)) ||
1826 nla_put_msecs(skb, NDTPA_DELAY_PROBE_TIME,
1827 NEIGH_VAR(parms, DELAY_PROBE_TIME)) ||
1828 nla_put_msecs(skb, NDTPA_RETRANS_TIME,
1829 NEIGH_VAR(parms, RETRANS_TIME)) ||
1830 nla_put_msecs(skb, NDTPA_ANYCAST_DELAY,
1831 NEIGH_VAR(parms, ANYCAST_DELAY)) ||
1832 nla_put_msecs(skb, NDTPA_PROXY_DELAY,
1833 NEIGH_VAR(parms, PROXY_DELAY)) ||
1834 nla_put_msecs(skb, NDTPA_LOCKTIME,
1835 NEIGH_VAR(parms, LOCKTIME)))
1836 goto nla_put_failure;
1837 return nla_nest_end(skb, nest);
1838
1839nla_put_failure:
1840 nla_nest_cancel(skb, nest);
1841 return -EMSGSIZE;
1842}
1843
1844static int neightbl_fill_info(struct sk_buff *skb, struct neigh_table *tbl,
1845 u32 pid, u32 seq, int type, int flags)
1846{
1847 struct nlmsghdr *nlh;
1848 struct ndtmsg *ndtmsg;
1849
1850 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndtmsg), flags);
1851 if (nlh == NULL)
1852 return -EMSGSIZE;
1853
1854 ndtmsg = nlmsg_data(nlh);
1855
1856 read_lock_bh(&tbl->lock);
1857 ndtmsg->ndtm_family = tbl->family;
1858 ndtmsg->ndtm_pad1 = 0;
1859 ndtmsg->ndtm_pad2 = 0;
1860
1861 if (nla_put_string(skb, NDTA_NAME, tbl->id) ||
1862 nla_put_msecs(skb, NDTA_GC_INTERVAL, tbl->gc_interval) ||
1863 nla_put_u32(skb, NDTA_THRESH1, tbl->gc_thresh1) ||
1864 nla_put_u32(skb, NDTA_THRESH2, tbl->gc_thresh2) ||
1865 nla_put_u32(skb, NDTA_THRESH3, tbl->gc_thresh3))
1866 goto nla_put_failure;
1867 {
1868 unsigned long now = jiffies;
1869 unsigned int flush_delta = now - tbl->last_flush;
1870 unsigned int rand_delta = now - tbl->last_rand;
1871 struct neigh_hash_table *nht;
1872 struct ndt_config ndc = {
1873 .ndtc_key_len = tbl->key_len,
1874 .ndtc_entry_size = tbl->entry_size,
1875 .ndtc_entries = atomic_read(&tbl->entries),
1876 .ndtc_last_flush = jiffies_to_msecs(flush_delta),
1877 .ndtc_last_rand = jiffies_to_msecs(rand_delta),
1878 .ndtc_proxy_qlen = tbl->proxy_queue.qlen,
1879 };
1880
1881 rcu_read_lock_bh();
1882 nht = rcu_dereference_bh(tbl->nht);
1883 ndc.ndtc_hash_rnd = nht->hash_rnd[0];
1884 ndc.ndtc_hash_mask = ((1 << nht->hash_shift) - 1);
1885 rcu_read_unlock_bh();
1886
1887 if (nla_put(skb, NDTA_CONFIG, sizeof(ndc), &ndc))
1888 goto nla_put_failure;
1889 }
1890
1891 {
1892 int cpu;
1893 struct ndt_stats ndst;
1894
1895 memset(&ndst, 0, sizeof(ndst));
1896
1897 for_each_possible_cpu(cpu) {
1898 struct neigh_statistics *st;
1899
1900 st = per_cpu_ptr(tbl->stats, cpu);
1901 ndst.ndts_allocs += st->allocs;
1902 ndst.ndts_destroys += st->destroys;
1903 ndst.ndts_hash_grows += st->hash_grows;
1904 ndst.ndts_res_failed += st->res_failed;
1905 ndst.ndts_lookups += st->lookups;
1906 ndst.ndts_hits += st->hits;
1907 ndst.ndts_rcv_probes_mcast += st->rcv_probes_mcast;
1908 ndst.ndts_rcv_probes_ucast += st->rcv_probes_ucast;
1909 ndst.ndts_periodic_gc_runs += st->periodic_gc_runs;
1910 ndst.ndts_forced_gc_runs += st->forced_gc_runs;
1911 }
1912
1913 if (nla_put(skb, NDTA_STATS, sizeof(ndst), &ndst))
1914 goto nla_put_failure;
1915 }
1916
1917 BUG_ON(tbl->parms.dev);
1918 if (neightbl_fill_parms(skb, &tbl->parms) < 0)
1919 goto nla_put_failure;
1920
1921 read_unlock_bh(&tbl->lock);
1922 return nlmsg_end(skb, nlh);
1923
1924nla_put_failure:
1925 read_unlock_bh(&tbl->lock);
1926 nlmsg_cancel(skb, nlh);
1927 return -EMSGSIZE;
1928}
1929
1930static int neightbl_fill_param_info(struct sk_buff *skb,
1931 struct neigh_table *tbl,
1932 struct neigh_parms *parms,
1933 u32 pid, u32 seq, int type,
1934 unsigned int flags)
1935{
1936 struct ndtmsg *ndtmsg;
1937 struct nlmsghdr *nlh;
1938
1939 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndtmsg), flags);
1940 if (nlh == NULL)
1941 return -EMSGSIZE;
1942
1943 ndtmsg = nlmsg_data(nlh);
1944
1945 read_lock_bh(&tbl->lock);
1946 ndtmsg->ndtm_family = tbl->family;
1947 ndtmsg->ndtm_pad1 = 0;
1948 ndtmsg->ndtm_pad2 = 0;
1949
1950 if (nla_put_string(skb, NDTA_NAME, tbl->id) < 0 ||
1951 neightbl_fill_parms(skb, parms) < 0)
1952 goto errout;
1953
1954 read_unlock_bh(&tbl->lock);
1955 return nlmsg_end(skb, nlh);
1956errout:
1957 read_unlock_bh(&tbl->lock);
1958 nlmsg_cancel(skb, nlh);
1959 return -EMSGSIZE;
1960}
1961
1962static const struct nla_policy nl_neightbl_policy[NDTA_MAX+1] = {
1963 [NDTA_NAME] = { .type = NLA_STRING },
1964 [NDTA_THRESH1] = { .type = NLA_U32 },
1965 [NDTA_THRESH2] = { .type = NLA_U32 },
1966 [NDTA_THRESH3] = { .type = NLA_U32 },
1967 [NDTA_GC_INTERVAL] = { .type = NLA_U64 },
1968 [NDTA_PARMS] = { .type = NLA_NESTED },
1969};
1970
1971static const struct nla_policy nl_ntbl_parm_policy[NDTPA_MAX+1] = {
1972 [NDTPA_IFINDEX] = { .type = NLA_U32 },
1973 [NDTPA_QUEUE_LEN] = { .type = NLA_U32 },
1974 [NDTPA_PROXY_QLEN] = { .type = NLA_U32 },
1975 [NDTPA_APP_PROBES] = { .type = NLA_U32 },
1976 [NDTPA_UCAST_PROBES] = { .type = NLA_U32 },
1977 [NDTPA_MCAST_PROBES] = { .type = NLA_U32 },
1978 [NDTPA_BASE_REACHABLE_TIME] = { .type = NLA_U64 },
1979 [NDTPA_GC_STALETIME] = { .type = NLA_U64 },
1980 [NDTPA_DELAY_PROBE_TIME] = { .type = NLA_U64 },
1981 [NDTPA_RETRANS_TIME] = { .type = NLA_U64 },
1982 [NDTPA_ANYCAST_DELAY] = { .type = NLA_U64 },
1983 [NDTPA_PROXY_DELAY] = { .type = NLA_U64 },
1984 [NDTPA_LOCKTIME] = { .type = NLA_U64 },
1985};
1986
1987static int neightbl_set(struct sk_buff *skb, struct nlmsghdr *nlh)
1988{
1989 struct net *net = sock_net(skb->sk);
1990 struct neigh_table *tbl;
1991 struct ndtmsg *ndtmsg;
1992 struct nlattr *tb[NDTA_MAX+1];
1993 int err;
1994
1995 err = nlmsg_parse(nlh, sizeof(*ndtmsg), tb, NDTA_MAX,
1996 nl_neightbl_policy);
1997 if (err < 0)
1998 goto errout;
1999
2000 if (tb[NDTA_NAME] == NULL) {
2001 err = -EINVAL;
2002 goto errout;
2003 }
2004
2005 ndtmsg = nlmsg_data(nlh);
2006 read_lock(&neigh_tbl_lock);
2007 for (tbl = neigh_tables; tbl; tbl = tbl->next) {
2008 if (ndtmsg->ndtm_family && tbl->family != ndtmsg->ndtm_family)
2009 continue;
2010
2011 if (nla_strcmp(tb[NDTA_NAME], tbl->id) == 0)
2012 break;
2013 }
2014
2015 if (tbl == NULL) {
2016 err = -ENOENT;
2017 goto errout_locked;
2018 }
2019
2020 /*
2021 * We acquire tbl->lock to be nice to the periodic timers and
2022 * make sure they always see a consistent set of values.
2023 */
2024 write_lock_bh(&tbl->lock);
2025
2026 if (tb[NDTA_PARMS]) {
2027 struct nlattr *tbp[NDTPA_MAX+1];
2028 struct neigh_parms *p;
2029 int i, ifindex = 0;
2030
2031 err = nla_parse_nested(tbp, NDTPA_MAX, tb[NDTA_PARMS],
2032 nl_ntbl_parm_policy);
2033 if (err < 0)
2034 goto errout_tbl_lock;
2035
2036 if (tbp[NDTPA_IFINDEX])
2037 ifindex = nla_get_u32(tbp[NDTPA_IFINDEX]);
2038
2039 p = lookup_neigh_parms(tbl, net, ifindex);
2040 if (p == NULL) {
2041 err = -ENOENT;
2042 goto errout_tbl_lock;
2043 }
2044
2045 for (i = 1; i <= NDTPA_MAX; i++) {
2046 if (tbp[i] == NULL)
2047 continue;
2048
2049 switch (i) {
2050 case NDTPA_QUEUE_LEN:
2051 NEIGH_VAR_SET(p, QUEUE_LEN_BYTES,
2052 nla_get_u32(tbp[i]) *
2053 SKB_TRUESIZE(ETH_FRAME_LEN));
2054 break;
2055 case NDTPA_QUEUE_LENBYTES:
2056 NEIGH_VAR_SET(p, QUEUE_LEN_BYTES,
2057 nla_get_u32(tbp[i]));
2058 break;
2059 case NDTPA_PROXY_QLEN:
2060 NEIGH_VAR_SET(p, PROXY_QLEN,
2061 nla_get_u32(tbp[i]));
2062 break;
2063 case NDTPA_APP_PROBES:
2064 NEIGH_VAR_SET(p, APP_PROBES,
2065 nla_get_u32(tbp[i]));
2066 break;
2067 case NDTPA_UCAST_PROBES:
2068 NEIGH_VAR_SET(p, UCAST_PROBES,
2069 nla_get_u32(tbp[i]));
2070 break;
2071 case NDTPA_MCAST_PROBES:
2072 NEIGH_VAR_SET(p, MCAST_PROBES,
2073 nla_get_u32(tbp[i]));
2074 break;
2075 case NDTPA_BASE_REACHABLE_TIME:
2076 NEIGH_VAR_SET(p, BASE_REACHABLE_TIME,
2077 nla_get_msecs(tbp[i]));
2078 break;
2079 case NDTPA_GC_STALETIME:
2080 NEIGH_VAR_SET(p, GC_STALETIME,
2081 nla_get_msecs(tbp[i]));
2082 break;
2083 case NDTPA_DELAY_PROBE_TIME:
2084 NEIGH_VAR_SET(p, DELAY_PROBE_TIME,
2085 nla_get_msecs(tbp[i]));
2086 break;
2087 case NDTPA_RETRANS_TIME:
2088 NEIGH_VAR_SET(p, RETRANS_TIME,
2089 nla_get_msecs(tbp[i]));
2090 break;
2091 case NDTPA_ANYCAST_DELAY:
2092 NEIGH_VAR_SET(p, ANYCAST_DELAY,
2093 nla_get_msecs(tbp[i]));
2094 break;
2095 case NDTPA_PROXY_DELAY:
2096 NEIGH_VAR_SET(p, PROXY_DELAY,
2097 nla_get_msecs(tbp[i]));
2098 break;
2099 case NDTPA_LOCKTIME:
2100 NEIGH_VAR_SET(p, LOCKTIME,
2101 nla_get_msecs(tbp[i]));
2102 break;
2103 }
2104 }
2105 }
2106
2107 err = -ENOENT;
2108 if ((tb[NDTA_THRESH1] || tb[NDTA_THRESH2] ||
2109 tb[NDTA_THRESH3] || tb[NDTA_GC_INTERVAL]) &&
2110 !net_eq(net, &init_net))
2111 goto errout_tbl_lock;
2112
2113 if (tb[NDTA_THRESH1])
2114 tbl->gc_thresh1 = nla_get_u32(tb[NDTA_THRESH1]);
2115
2116 if (tb[NDTA_THRESH2])
2117 tbl->gc_thresh2 = nla_get_u32(tb[NDTA_THRESH2]);
2118
2119 if (tb[NDTA_THRESH3])
2120 tbl->gc_thresh3 = nla_get_u32(tb[NDTA_THRESH3]);
2121
2122 if (tb[NDTA_GC_INTERVAL])
2123 tbl->gc_interval = nla_get_msecs(tb[NDTA_GC_INTERVAL]);
2124
2125 err = 0;
2126
2127errout_tbl_lock:
2128 write_unlock_bh(&tbl->lock);
2129errout_locked:
2130 read_unlock(&neigh_tbl_lock);
2131errout:
2132 return err;
2133}
2134
2135static int neightbl_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
2136{
2137 struct net *net = sock_net(skb->sk);
2138 int family, tidx, nidx = 0;
2139 int tbl_skip = cb->args[0];
2140 int neigh_skip = cb->args[1];
2141 struct neigh_table *tbl;
2142
2143 family = ((struct rtgenmsg *) nlmsg_data(cb->nlh))->rtgen_family;
2144
2145 read_lock(&neigh_tbl_lock);
2146 for (tbl = neigh_tables, tidx = 0; tbl; tbl = tbl->next, tidx++) {
2147 struct neigh_parms *p;
2148
2149 if (tidx < tbl_skip || (family && tbl->family != family))
2150 continue;
2151
2152 if (neightbl_fill_info(skb, tbl, NETLINK_CB(cb->skb).portid,
2153 cb->nlh->nlmsg_seq, RTM_NEWNEIGHTBL,
2154 NLM_F_MULTI) <= 0)
2155 break;
2156
2157 for (nidx = 0, p = tbl->parms.next; p; p = p->next) {
2158 if (!net_eq(neigh_parms_net(p), net))
2159 continue;
2160
2161 if (nidx < neigh_skip)
2162 goto next;
2163
2164 if (neightbl_fill_param_info(skb, tbl, p,
2165 NETLINK_CB(cb->skb).portid,
2166 cb->nlh->nlmsg_seq,
2167 RTM_NEWNEIGHTBL,
2168 NLM_F_MULTI) <= 0)
2169 goto out;
2170 next:
2171 nidx++;
2172 }
2173
2174 neigh_skip = 0;
2175 }
2176out:
2177 read_unlock(&neigh_tbl_lock);
2178 cb->args[0] = tidx;
2179 cb->args[1] = nidx;
2180
2181 return skb->len;
2182}
2183
2184static int neigh_fill_info(struct sk_buff *skb, struct neighbour *neigh,
2185 u32 pid, u32 seq, int type, unsigned int flags)
2186{
2187 unsigned long now = jiffies;
2188 struct nda_cacheinfo ci;
2189 struct nlmsghdr *nlh;
2190 struct ndmsg *ndm;
2191
2192 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndm), flags);
2193 if (nlh == NULL)
2194 return -EMSGSIZE;
2195
2196 ndm = nlmsg_data(nlh);
2197 ndm->ndm_family = neigh->ops->family;
2198 ndm->ndm_pad1 = 0;
2199 ndm->ndm_pad2 = 0;
2200 ndm->ndm_flags = neigh->flags;
2201 ndm->ndm_type = neigh->type;
2202 ndm->ndm_ifindex = neigh->dev->ifindex;
2203
2204 if (nla_put(skb, NDA_DST, neigh->tbl->key_len, neigh->primary_key))
2205 goto nla_put_failure;
2206
2207 read_lock_bh(&neigh->lock);
2208 ndm->ndm_state = neigh->nud_state;
2209 if (neigh->nud_state & NUD_VALID) {
2210 char haddr[MAX_ADDR_LEN];
2211
2212 neigh_ha_snapshot(haddr, neigh, neigh->dev);
2213 if (nla_put(skb, NDA_LLADDR, neigh->dev->addr_len, haddr) < 0) {
2214 read_unlock_bh(&neigh->lock);
2215 goto nla_put_failure;
2216 }
2217 }
2218
2219 ci.ndm_used = jiffies_to_clock_t(now - neigh->used);
2220 ci.ndm_confirmed = jiffies_to_clock_t(now - neigh->confirmed);
2221 ci.ndm_updated = jiffies_to_clock_t(now - neigh->updated);
2222 ci.ndm_refcnt = atomic_read(&neigh->refcnt) - 1;
2223 read_unlock_bh(&neigh->lock);
2224
2225 if (nla_put_u32(skb, NDA_PROBES, atomic_read(&neigh->probes)) ||
2226 nla_put(skb, NDA_CACHEINFO, sizeof(ci), &ci))
2227 goto nla_put_failure;
2228
2229 return nlmsg_end(skb, nlh);
2230
2231nla_put_failure:
2232 nlmsg_cancel(skb, nlh);
2233 return -EMSGSIZE;
2234}
2235
2236static int pneigh_fill_info(struct sk_buff *skb, struct pneigh_entry *pn,
2237 u32 pid, u32 seq, int type, unsigned int flags,
2238 struct neigh_table *tbl)
2239{
2240 struct nlmsghdr *nlh;
2241 struct ndmsg *ndm;
2242
2243 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndm), flags);
2244 if (nlh == NULL)
2245 return -EMSGSIZE;
2246
2247 ndm = nlmsg_data(nlh);
2248 ndm->ndm_family = tbl->family;
2249 ndm->ndm_pad1 = 0;
2250 ndm->ndm_pad2 = 0;
2251 ndm->ndm_flags = pn->flags | NTF_PROXY;
2252 ndm->ndm_type = NDA_DST;
2253 ndm->ndm_ifindex = pn->dev->ifindex;
2254 ndm->ndm_state = NUD_NONE;
2255
2256 if (nla_put(skb, NDA_DST, tbl->key_len, pn->key))
2257 goto nla_put_failure;
2258
2259 return nlmsg_end(skb, nlh);
2260
2261nla_put_failure:
2262 nlmsg_cancel(skb, nlh);
2263 return -EMSGSIZE;
2264}
2265
2266static void neigh_update_notify(struct neighbour *neigh)
2267{
2268 call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, neigh);
2269 __neigh_notify(neigh, RTM_NEWNEIGH, 0);
2270}
2271
2272static int neigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb,
2273 struct netlink_callback *cb)
2274{
2275 struct net *net = sock_net(skb->sk);
2276 struct neighbour *n;
2277 int rc, h, s_h = cb->args[1];
2278 int idx, s_idx = idx = cb->args[2];
2279 struct neigh_hash_table *nht;
2280
2281 rcu_read_lock_bh();
2282 nht = rcu_dereference_bh(tbl->nht);
2283
2284 for (h = s_h; h < (1 << nht->hash_shift); h++) {
2285 if (h > s_h)
2286 s_idx = 0;
2287 for (n = rcu_dereference_bh(nht->hash_buckets[h]), idx = 0;
2288 n != NULL;
2289 n = rcu_dereference_bh(n->next)) {
2290 if (!net_eq(dev_net(n->dev), net))
2291 continue;
2292 if (idx < s_idx)
2293 goto next;
2294 if (neigh_fill_info(skb, n, NETLINK_CB(cb->skb).portid,
2295 cb->nlh->nlmsg_seq,
2296 RTM_NEWNEIGH,
2297 NLM_F_MULTI) <= 0) {
2298 rc = -1;
2299 goto out;
2300 }
2301next:
2302 idx++;
2303 }
2304 }
2305 rc = skb->len;
2306out:
2307 rcu_read_unlock_bh();
2308 cb->args[1] = h;
2309 cb->args[2] = idx;
2310 return rc;
2311}
2312
2313static int pneigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb,
2314 struct netlink_callback *cb)
2315{
2316 struct pneigh_entry *n;
2317 struct net *net = sock_net(skb->sk);
2318 int rc, h, s_h = cb->args[3];
2319 int idx, s_idx = idx = cb->args[4];
2320
2321 read_lock_bh(&tbl->lock);
2322
2323 for (h = s_h; h <= PNEIGH_HASHMASK; h++) {
2324 if (h > s_h)
2325 s_idx = 0;
2326 for (n = tbl->phash_buckets[h], idx = 0; n; n = n->next) {
2327 if (dev_net(n->dev) != net)
2328 continue;
2329 if (idx < s_idx)
2330 goto next;
2331 if (pneigh_fill_info(skb, n, NETLINK_CB(cb->skb).portid,
2332 cb->nlh->nlmsg_seq,
2333 RTM_NEWNEIGH,
2334 NLM_F_MULTI, tbl) <= 0) {
2335 read_unlock_bh(&tbl->lock);
2336 rc = -1;
2337 goto out;
2338 }
2339 next:
2340 idx++;
2341 }
2342 }
2343
2344 read_unlock_bh(&tbl->lock);
2345 rc = skb->len;
2346out:
2347 cb->args[3] = h;
2348 cb->args[4] = idx;
2349 return rc;
2350
2351}
2352
2353static int neigh_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
2354{
2355 struct neigh_table *tbl;
2356 int t, family, s_t;
2357 int proxy = 0;
2358 int err;
2359
2360 read_lock(&neigh_tbl_lock);
2361 family = ((struct rtgenmsg *) nlmsg_data(cb->nlh))->rtgen_family;
2362
2363 /* check for full ndmsg structure presence, family member is
2364 * the same for both structures
2365 */
2366 if (nlmsg_len(cb->nlh) >= sizeof(struct ndmsg) &&
2367 ((struct ndmsg *) nlmsg_data(cb->nlh))->ndm_flags == NTF_PROXY)
2368 proxy = 1;
2369
2370 s_t = cb->args[0];
2371
2372 for (tbl = neigh_tables, t = 0; tbl;
2373 tbl = tbl->next, t++) {
2374 if (t < s_t || (family && tbl->family != family))
2375 continue;
2376 if (t > s_t)
2377 memset(&cb->args[1], 0, sizeof(cb->args) -
2378 sizeof(cb->args[0]));
2379 if (proxy)
2380 err = pneigh_dump_table(tbl, skb, cb);
2381 else
2382 err = neigh_dump_table(tbl, skb, cb);
2383 if (err < 0)
2384 break;
2385 }
2386 read_unlock(&neigh_tbl_lock);
2387
2388 cb->args[0] = t;
2389 return skb->len;
2390}
2391
2392void neigh_for_each(struct neigh_table *tbl, void (*cb)(struct neighbour *, void *), void *cookie)
2393{
2394 int chain;
2395 struct neigh_hash_table *nht;
2396
2397 rcu_read_lock_bh();
2398 nht = rcu_dereference_bh(tbl->nht);
2399
2400 read_lock(&tbl->lock); /* avoid resizes */
2401 for (chain = 0; chain < (1 << nht->hash_shift); chain++) {
2402 struct neighbour *n;
2403
2404 for (n = rcu_dereference_bh(nht->hash_buckets[chain]);
2405 n != NULL;
2406 n = rcu_dereference_bh(n->next))
2407 cb(n, cookie);
2408 }
2409 read_unlock(&tbl->lock);
2410 rcu_read_unlock_bh();
2411}
2412EXPORT_SYMBOL(neigh_for_each);
2413
2414/* The tbl->lock must be held as a writer and BH disabled. */
2415void __neigh_for_each_release(struct neigh_table *tbl,
2416 int (*cb)(struct neighbour *))
2417{
2418 int chain;
2419 struct neigh_hash_table *nht;
2420
2421 nht = rcu_dereference_protected(tbl->nht,
2422 lockdep_is_held(&tbl->lock));
2423 for (chain = 0; chain < (1 << nht->hash_shift); chain++) {
2424 struct neighbour *n;
2425 struct neighbour __rcu **np;
2426
2427 np = &nht->hash_buckets[chain];
2428 while ((n = rcu_dereference_protected(*np,
2429 lockdep_is_held(&tbl->lock))) != NULL) {
2430 int release;
2431
2432 write_lock(&n->lock);
2433 release = cb(n);
2434 if (release) {
2435 rcu_assign_pointer(*np,
2436 rcu_dereference_protected(n->next,
2437 lockdep_is_held(&tbl->lock)));
2438 n->dead = 1;
2439 } else
2440 np = &n->next;
2441 write_unlock(&n->lock);
2442 if (release)
2443 neigh_cleanup_and_release(n);
2444 }
2445 }
2446}
2447EXPORT_SYMBOL(__neigh_for_each_release);
2448
2449#ifdef CONFIG_PROC_FS
2450
2451static struct neighbour *neigh_get_first(struct seq_file *seq)
2452{
2453 struct neigh_seq_state *state = seq->private;
2454 struct net *net = seq_file_net(seq);
2455 struct neigh_hash_table *nht = state->nht;
2456 struct neighbour *n = NULL;
2457 int bucket = state->bucket;
2458
2459 state->flags &= ~NEIGH_SEQ_IS_PNEIGH;
2460 for (bucket = 0; bucket < (1 << nht->hash_shift); bucket++) {
2461 n = rcu_dereference_bh(nht->hash_buckets[bucket]);
2462
2463 while (n) {
2464 if (!net_eq(dev_net(n->dev), net))
2465 goto next;
2466 if (state->neigh_sub_iter) {
2467 loff_t fakep = 0;
2468 void *v;
2469
2470 v = state->neigh_sub_iter(state, n, &fakep);
2471 if (!v)
2472 goto next;
2473 }
2474 if (!(state->flags & NEIGH_SEQ_SKIP_NOARP))
2475 break;
2476 if (n->nud_state & ~NUD_NOARP)
2477 break;
2478next:
2479 n = rcu_dereference_bh(n->next);
2480 }
2481
2482 if (n)
2483 break;
2484 }
2485 state->bucket = bucket;
2486
2487 return n;
2488}
2489
2490static struct neighbour *neigh_get_next(struct seq_file *seq,
2491 struct neighbour *n,
2492 loff_t *pos)
2493{
2494 struct neigh_seq_state *state = seq->private;
2495 struct net *net = seq_file_net(seq);
2496 struct neigh_hash_table *nht = state->nht;
2497
2498 if (state->neigh_sub_iter) {
2499 void *v = state->neigh_sub_iter(state, n, pos);
2500 if (v)
2501 return n;
2502 }
2503 n = rcu_dereference_bh(n->next);
2504
2505 while (1) {
2506 while (n) {
2507 if (!net_eq(dev_net(n->dev), net))
2508 goto next;
2509 if (state->neigh_sub_iter) {
2510 void *v = state->neigh_sub_iter(state, n, pos);
2511 if (v)
2512 return n;
2513 goto next;
2514 }
2515 if (!(state->flags & NEIGH_SEQ_SKIP_NOARP))
2516 break;
2517
2518 if (n->nud_state & ~NUD_NOARP)
2519 break;
2520next:
2521 n = rcu_dereference_bh(n->next);
2522 }
2523
2524 if (n)
2525 break;
2526
2527 if (++state->bucket >= (1 << nht->hash_shift))
2528 break;
2529
2530 n = rcu_dereference_bh(nht->hash_buckets[state->bucket]);
2531 }
2532
2533 if (n && pos)
2534 --(*pos);
2535 return n;
2536}
2537
2538static struct neighbour *neigh_get_idx(struct seq_file *seq, loff_t *pos)
2539{
2540 struct neighbour *n = neigh_get_first(seq);
2541
2542 if (n) {
2543 --(*pos);
2544 while (*pos) {
2545 n = neigh_get_next(seq, n, pos);
2546 if (!n)
2547 break;
2548 }
2549 }
2550 return *pos ? NULL : n;
2551}
2552
2553static struct pneigh_entry *pneigh_get_first(struct seq_file *seq)
2554{
2555 struct neigh_seq_state *state = seq->private;
2556 struct net *net = seq_file_net(seq);
2557 struct neigh_table *tbl = state->tbl;
2558 struct pneigh_entry *pn = NULL;
2559 int bucket = state->bucket;
2560
2561 state->flags |= NEIGH_SEQ_IS_PNEIGH;
2562 for (bucket = 0; bucket <= PNEIGH_HASHMASK; bucket++) {
2563 pn = tbl->phash_buckets[bucket];
2564 while (pn && !net_eq(pneigh_net(pn), net))
2565 pn = pn->next;
2566 if (pn)
2567 break;
2568 }
2569 state->bucket = bucket;
2570
2571 return pn;
2572}
2573
2574static struct pneigh_entry *pneigh_get_next(struct seq_file *seq,
2575 struct pneigh_entry *pn,
2576 loff_t *pos)
2577{
2578 struct neigh_seq_state *state = seq->private;
2579 struct net *net = seq_file_net(seq);
2580 struct neigh_table *tbl = state->tbl;
2581
2582 do {
2583 pn = pn->next;
2584 } while (pn && !net_eq(pneigh_net(pn), net));
2585
2586 while (!pn) {
2587 if (++state->bucket > PNEIGH_HASHMASK)
2588 break;
2589 pn = tbl->phash_buckets[state->bucket];
2590 while (pn && !net_eq(pneigh_net(pn), net))
2591 pn = pn->next;
2592 if (pn)
2593 break;
2594 }
2595
2596 if (pn && pos)
2597 --(*pos);
2598
2599 return pn;
2600}
2601
2602static struct pneigh_entry *pneigh_get_idx(struct seq_file *seq, loff_t *pos)
2603{
2604 struct pneigh_entry *pn = pneigh_get_first(seq);
2605
2606 if (pn) {
2607 --(*pos);
2608 while (*pos) {
2609 pn = pneigh_get_next(seq, pn, pos);
2610 if (!pn)
2611 break;
2612 }
2613 }
2614 return *pos ? NULL : pn;
2615}
2616
2617static void *neigh_get_idx_any(struct seq_file *seq, loff_t *pos)
2618{
2619 struct neigh_seq_state *state = seq->private;
2620 void *rc;
2621 loff_t idxpos = *pos;
2622
2623 rc = neigh_get_idx(seq, &idxpos);
2624 if (!rc && !(state->flags & NEIGH_SEQ_NEIGH_ONLY))
2625 rc = pneigh_get_idx(seq, &idxpos);
2626
2627 return rc;
2628}
2629
2630void *neigh_seq_start(struct seq_file *seq, loff_t *pos, struct neigh_table *tbl, unsigned int neigh_seq_flags)
2631 __acquires(rcu_bh)
2632{
2633 struct neigh_seq_state *state = seq->private;
2634
2635 state->tbl = tbl;
2636 state->bucket = 0;
2637 state->flags = (neigh_seq_flags & ~NEIGH_SEQ_IS_PNEIGH);
2638
2639 rcu_read_lock_bh();
2640 state->nht = rcu_dereference_bh(tbl->nht);
2641
2642 return *pos ? neigh_get_idx_any(seq, pos) : SEQ_START_TOKEN;
2643}
2644EXPORT_SYMBOL(neigh_seq_start);
2645
2646void *neigh_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2647{
2648 struct neigh_seq_state *state;
2649 void *rc;
2650
2651 if (v == SEQ_START_TOKEN) {
2652 rc = neigh_get_first(seq);
2653 goto out;
2654 }
2655
2656 state = seq->private;
2657 if (!(state->flags & NEIGH_SEQ_IS_PNEIGH)) {
2658 rc = neigh_get_next(seq, v, NULL);
2659 if (rc)
2660 goto out;
2661 if (!(state->flags & NEIGH_SEQ_NEIGH_ONLY))
2662 rc = pneigh_get_first(seq);
2663 } else {
2664 BUG_ON(state->flags & NEIGH_SEQ_NEIGH_ONLY);
2665 rc = pneigh_get_next(seq, v, NULL);
2666 }
2667out:
2668 ++(*pos);
2669 return rc;
2670}
2671EXPORT_SYMBOL(neigh_seq_next);
2672
2673void neigh_seq_stop(struct seq_file *seq, void *v)
2674 __releases(rcu_bh)
2675{
2676 rcu_read_unlock_bh();
2677}
2678EXPORT_SYMBOL(neigh_seq_stop);
2679
2680/* statistics via seq_file */
2681
2682static void *neigh_stat_seq_start(struct seq_file *seq, loff_t *pos)
2683{
2684 struct neigh_table *tbl = seq->private;
2685 int cpu;
2686
2687 if (*pos == 0)
2688 return SEQ_START_TOKEN;
2689
2690 for (cpu = *pos-1; cpu < nr_cpu_ids; ++cpu) {
2691 if (!cpu_possible(cpu))
2692 continue;
2693 *pos = cpu+1;
2694 return per_cpu_ptr(tbl->stats, cpu);
2695 }
2696 return NULL;
2697}
2698
2699static void *neigh_stat_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2700{
2701 struct neigh_table *tbl = seq->private;
2702 int cpu;
2703
2704 for (cpu = *pos; cpu < nr_cpu_ids; ++cpu) {
2705 if (!cpu_possible(cpu))
2706 continue;
2707 *pos = cpu+1;
2708 return per_cpu_ptr(tbl->stats, cpu);
2709 }
2710 return NULL;
2711}
2712
2713static void neigh_stat_seq_stop(struct seq_file *seq, void *v)
2714{
2715
2716}
2717
2718static int neigh_stat_seq_show(struct seq_file *seq, void *v)
2719{
2720 struct neigh_table *tbl = seq->private;
2721 struct neigh_statistics *st = v;
2722
2723 if (v == SEQ_START_TOKEN) {
2724 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\n");
2725 return 0;
2726 }
2727
2728 seq_printf(seq, "%08x %08lx %08lx %08lx %08lx %08lx %08lx "
2729 "%08lx %08lx %08lx %08lx %08lx\n",
2730 atomic_read(&tbl->entries),
2731
2732 st->allocs,
2733 st->destroys,
2734 st->hash_grows,
2735
2736 st->lookups,
2737 st->hits,
2738
2739 st->res_failed,
2740
2741 st->rcv_probes_mcast,
2742 st->rcv_probes_ucast,
2743
2744 st->periodic_gc_runs,
2745 st->forced_gc_runs,
2746 st->unres_discards
2747 );
2748
2749 return 0;
2750}
2751
2752static const struct seq_operations neigh_stat_seq_ops = {
2753 .start = neigh_stat_seq_start,
2754 .next = neigh_stat_seq_next,
2755 .stop = neigh_stat_seq_stop,
2756 .show = neigh_stat_seq_show,
2757};
2758
2759static int neigh_stat_seq_open(struct inode *inode, struct file *file)
2760{
2761 int ret = seq_open(file, &neigh_stat_seq_ops);
2762
2763 if (!ret) {
2764 struct seq_file *sf = file->private_data;
2765 sf->private = PDE_DATA(inode);
2766 }
2767 return ret;
2768};
2769
2770static const struct file_operations neigh_stat_seq_fops = {
2771 .owner = THIS_MODULE,
2772 .open = neigh_stat_seq_open,
2773 .read = seq_read,
2774 .llseek = seq_lseek,
2775 .release = seq_release,
2776};
2777
2778#endif /* CONFIG_PROC_FS */
2779
2780static inline size_t neigh_nlmsg_size(void)
2781{
2782 return NLMSG_ALIGN(sizeof(struct ndmsg))
2783 + nla_total_size(MAX_ADDR_LEN) /* NDA_DST */
2784 + nla_total_size(MAX_ADDR_LEN) /* NDA_LLADDR */
2785 + nla_total_size(sizeof(struct nda_cacheinfo))
2786 + nla_total_size(4); /* NDA_PROBES */
2787}
2788
2789static void __neigh_notify(struct neighbour *n, int type, int flags)
2790{
2791 struct net *net = dev_net(n->dev);
2792 struct sk_buff *skb;
2793 int err = -ENOBUFS;
2794
2795 skb = nlmsg_new(neigh_nlmsg_size(), GFP_ATOMIC);
2796 if (skb == NULL)
2797 goto errout;
2798
2799 err = neigh_fill_info(skb, n, 0, 0, type, flags);
2800 if (err < 0) {
2801 /* -EMSGSIZE implies BUG in neigh_nlmsg_size() */
2802 WARN_ON(err == -EMSGSIZE);
2803 kfree_skb(skb);
2804 goto errout;
2805 }
2806 rtnl_notify(skb, net, 0, RTNLGRP_NEIGH, NULL, GFP_ATOMIC);
2807 return;
2808errout:
2809 if (err < 0)
2810 rtnl_set_sk_err(net, RTNLGRP_NEIGH, err);
2811}
2812
2813void neigh_app_ns(struct neighbour *n)
2814{
2815 __neigh_notify(n, RTM_GETNEIGH, NLM_F_REQUEST);
2816}
2817EXPORT_SYMBOL(neigh_app_ns);
2818
2819#ifdef CONFIG_SYSCTL
2820static int zero;
2821static int int_max = INT_MAX;
2822static int unres_qlen_max = INT_MAX / SKB_TRUESIZE(ETH_FRAME_LEN);
2823
2824static int proc_unres_qlen(struct ctl_table *ctl, int write,
2825 void __user *buffer, size_t *lenp, loff_t *ppos)
2826{
2827 int size, ret;
2828 struct ctl_table tmp = *ctl;
2829
2830 tmp.extra1 = &zero;
2831 tmp.extra2 = &unres_qlen_max;
2832 tmp.data = &size;
2833
2834 size = *(int *)ctl->data / SKB_TRUESIZE(ETH_FRAME_LEN);
2835 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
2836
2837 if (write && !ret)
2838 *(int *)ctl->data = size * SKB_TRUESIZE(ETH_FRAME_LEN);
2839 return ret;
2840}
2841
2842static struct neigh_parms *neigh_get_dev_parms_rcu(struct net_device *dev,
2843 int family)
2844{
2845 switch (family) {
2846 case AF_INET:
2847 return __in_dev_arp_parms_get_rcu(dev);
2848 case AF_INET6:
2849 return __in6_dev_nd_parms_get_rcu(dev);
2850 }
2851 return NULL;
2852}
2853
2854static void neigh_copy_dflt_parms(struct net *net, struct neigh_parms *p,
2855 int index)
2856{
2857 struct net_device *dev;
2858 int family = neigh_parms_family(p);
2859
2860 rcu_read_lock();
2861 for_each_netdev_rcu(net, dev) {
2862 struct neigh_parms *dst_p =
2863 neigh_get_dev_parms_rcu(dev, family);
2864
2865 if (dst_p && !test_bit(index, dst_p->data_state))
2866 dst_p->data[index] = p->data[index];
2867 }
2868 rcu_read_unlock();
2869}
2870
2871static void neigh_proc_update(struct ctl_table *ctl, int write)
2872{
2873 struct net_device *dev = ctl->extra1;
2874 struct neigh_parms *p = ctl->extra2;
2875 struct net *net = neigh_parms_net(p);
2876 int index = (int *) ctl->data - p->data;
2877
2878 if (!write)
2879 return;
2880
2881 set_bit(index, p->data_state);
2882 if (!dev) /* NULL dev means this is default value */
2883 neigh_copy_dflt_parms(net, p, index);
2884}
2885
2886static int neigh_proc_dointvec_zero_intmax(struct ctl_table *ctl, int write,
2887 void __user *buffer,
2888 size_t *lenp, loff_t *ppos)
2889{
2890 struct ctl_table tmp = *ctl;
2891 int ret;
2892
2893 tmp.extra1 = &zero;
2894 tmp.extra2 = &int_max;
2895
2896 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
2897 neigh_proc_update(ctl, write);
2898 return ret;
2899}
2900
2901int neigh_proc_dointvec(struct ctl_table *ctl, int write,
2902 void __user *buffer, size_t *lenp, loff_t *ppos)
2903{
2904 int ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
2905
2906 neigh_proc_update(ctl, write);
2907 return ret;
2908}
2909EXPORT_SYMBOL(neigh_proc_dointvec);
2910
2911int neigh_proc_dointvec_jiffies(struct ctl_table *ctl, int write,
2912 void __user *buffer,
2913 size_t *lenp, loff_t *ppos)
2914{
2915 int ret = proc_dointvec_jiffies(ctl, write, buffer, lenp, ppos);
2916
2917 neigh_proc_update(ctl, write);
2918 return ret;
2919}
2920EXPORT_SYMBOL(neigh_proc_dointvec_jiffies);
2921
2922static int neigh_proc_dointvec_userhz_jiffies(struct ctl_table *ctl, int write,
2923 void __user *buffer,
2924 size_t *lenp, loff_t *ppos)
2925{
2926 int ret = proc_dointvec_userhz_jiffies(ctl, write, buffer, lenp, ppos);
2927
2928 neigh_proc_update(ctl, write);
2929 return ret;
2930}
2931
2932int neigh_proc_dointvec_ms_jiffies(struct ctl_table *ctl, int write,
2933 void __user *buffer,
2934 size_t *lenp, loff_t *ppos)
2935{
2936 int ret = proc_dointvec_ms_jiffies(ctl, write, buffer, lenp, ppos);
2937
2938 neigh_proc_update(ctl, write);
2939 return ret;
2940}
2941EXPORT_SYMBOL(neigh_proc_dointvec_ms_jiffies);
2942
2943static int neigh_proc_dointvec_unres_qlen(struct ctl_table *ctl, int write,
2944 void __user *buffer,
2945 size_t *lenp, loff_t *ppos)
2946{
2947 int ret = proc_unres_qlen(ctl, write, buffer, lenp, ppos);
2948
2949 neigh_proc_update(ctl, write);
2950 return ret;
2951}
2952
2953#define NEIGH_PARMS_DATA_OFFSET(index) \
2954 (&((struct neigh_parms *) 0)->data[index])
2955
2956#define NEIGH_SYSCTL_ENTRY(attr, data_attr, name, mval, proc) \
2957 [NEIGH_VAR_ ## attr] = { \
2958 .procname = name, \
2959 .data = NEIGH_PARMS_DATA_OFFSET(NEIGH_VAR_ ## data_attr), \
2960 .maxlen = sizeof(int), \
2961 .mode = mval, \
2962 .proc_handler = proc, \
2963 }
2964
2965#define NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(attr, name) \
2966 NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_zero_intmax)
2967
2968#define NEIGH_SYSCTL_JIFFIES_ENTRY(attr, name) \
2969 NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_jiffies)
2970
2971#define NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(attr, name) \
2972 NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_userhz_jiffies)
2973
2974#define NEIGH_SYSCTL_MS_JIFFIES_ENTRY(attr, name) \
2975 NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_ms_jiffies)
2976
2977#define NEIGH_SYSCTL_MS_JIFFIES_REUSED_ENTRY(attr, data_attr, name) \
2978 NEIGH_SYSCTL_ENTRY(attr, data_attr, name, 0644, neigh_proc_dointvec_ms_jiffies)
2979
2980#define NEIGH_SYSCTL_UNRES_QLEN_REUSED_ENTRY(attr, data_attr, name) \
2981 NEIGH_SYSCTL_ENTRY(attr, data_attr, name, 0644, neigh_proc_dointvec_unres_qlen)
2982
2983static struct neigh_sysctl_table {
2984 struct ctl_table_header *sysctl_header;
2985 struct ctl_table neigh_vars[NEIGH_VAR_MAX + 1];
2986} neigh_sysctl_template __read_mostly = {
2987 .neigh_vars = {
2988 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(MCAST_PROBES, "mcast_solicit"),
2989 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(UCAST_PROBES, "ucast_solicit"),
2990 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(APP_PROBES, "app_solicit"),
2991 NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(RETRANS_TIME, "retrans_time"),
2992 NEIGH_SYSCTL_JIFFIES_ENTRY(BASE_REACHABLE_TIME, "base_reachable_time"),
2993 NEIGH_SYSCTL_JIFFIES_ENTRY(DELAY_PROBE_TIME, "delay_first_probe_time"),
2994 NEIGH_SYSCTL_JIFFIES_ENTRY(GC_STALETIME, "gc_stale_time"),
2995 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(QUEUE_LEN_BYTES, "unres_qlen_bytes"),
2996 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(PROXY_QLEN, "proxy_qlen"),
2997 NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(ANYCAST_DELAY, "anycast_delay"),
2998 NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(PROXY_DELAY, "proxy_delay"),
2999 NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(LOCKTIME, "locktime"),
3000 NEIGH_SYSCTL_UNRES_QLEN_REUSED_ENTRY(QUEUE_LEN, QUEUE_LEN_BYTES, "unres_qlen"),
3001 NEIGH_SYSCTL_MS_JIFFIES_REUSED_ENTRY(RETRANS_TIME_MS, RETRANS_TIME, "retrans_time_ms"),
3002 NEIGH_SYSCTL_MS_JIFFIES_REUSED_ENTRY(BASE_REACHABLE_TIME_MS, BASE_REACHABLE_TIME, "base_reachable_time_ms"),
3003 [NEIGH_VAR_GC_INTERVAL] = {
3004 .procname = "gc_interval",
3005 .maxlen = sizeof(int),
3006 .mode = 0644,
3007 .proc_handler = proc_dointvec_jiffies,
3008 },
3009 [NEIGH_VAR_GC_THRESH1] = {
3010 .procname = "gc_thresh1",
3011 .maxlen = sizeof(int),
3012 .mode = 0644,
3013 .extra1 = &zero,
3014 .extra2 = &int_max,
3015 .proc_handler = proc_dointvec_minmax,
3016 },
3017 [NEIGH_VAR_GC_THRESH2] = {
3018 .procname = "gc_thresh2",
3019 .maxlen = sizeof(int),
3020 .mode = 0644,
3021 .extra1 = &zero,
3022 .extra2 = &int_max,
3023 .proc_handler = proc_dointvec_minmax,
3024 },
3025 [NEIGH_VAR_GC_THRESH3] = {
3026 .procname = "gc_thresh3",
3027 .maxlen = sizeof(int),
3028 .mode = 0644,
3029 .extra1 = &zero,
3030 .extra2 = &int_max,
3031 .proc_handler = proc_dointvec_minmax,
3032 },
3033 {},
3034 },
3035};
3036
3037int neigh_sysctl_register(struct net_device *dev, struct neigh_parms *p,
3038 proc_handler *handler)
3039{
3040 int i;
3041 struct neigh_sysctl_table *t;
3042 const char *dev_name_source;
3043 char neigh_path[ sizeof("net//neigh/") + IFNAMSIZ + IFNAMSIZ ];
3044 char *p_name;
3045
3046 t = kmemdup(&neigh_sysctl_template, sizeof(*t), GFP_KERNEL);
3047 if (!t)
3048 goto err;
3049
3050 for (i = 0; i < NEIGH_VAR_GC_INTERVAL; i++) {
3051 t->neigh_vars[i].data += (long) p;
3052 t->neigh_vars[i].extra1 = dev;
3053 t->neigh_vars[i].extra2 = p;
3054 }
3055
3056 if (dev) {
3057 dev_name_source = dev->name;
3058 /* Terminate the table early */
3059 memset(&t->neigh_vars[NEIGH_VAR_GC_INTERVAL], 0,
3060 sizeof(t->neigh_vars[NEIGH_VAR_GC_INTERVAL]));
3061 } else {
3062 dev_name_source = "default";
3063 t->neigh_vars[NEIGH_VAR_GC_INTERVAL].data = (int *)(p + 1);
3064 t->neigh_vars[NEIGH_VAR_GC_THRESH1].data = (int *)(p + 1) + 1;
3065 t->neigh_vars[NEIGH_VAR_GC_THRESH2].data = (int *)(p + 1) + 2;
3066 t->neigh_vars[NEIGH_VAR_GC_THRESH3].data = (int *)(p + 1) + 3;
3067 }
3068
3069 if (handler) {
3070 /* RetransTime */
3071 t->neigh_vars[NEIGH_VAR_RETRANS_TIME].proc_handler = handler;
3072 /* ReachableTime */
3073 t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME].proc_handler = handler;
3074 /* RetransTime (in milliseconds)*/
3075 t->neigh_vars[NEIGH_VAR_RETRANS_TIME_MS].proc_handler = handler;
3076 /* ReachableTime (in milliseconds) */
3077 t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME_MS].proc_handler = handler;
3078 }
3079
3080 /* Don't export sysctls to unprivileged users */
3081 if (neigh_parms_net(p)->user_ns != &init_user_ns)
3082 t->neigh_vars[0].procname = NULL;
3083
3084 switch (neigh_parms_family(p)) {
3085 case AF_INET:
3086 p_name = "ipv4";
3087 break;
3088 case AF_INET6:
3089 p_name = "ipv6";
3090 break;
3091 default:
3092 BUG();
3093 }
3094
3095 snprintf(neigh_path, sizeof(neigh_path), "net/%s/neigh/%s",
3096 p_name, dev_name_source);
3097 t->sysctl_header =
3098 register_net_sysctl(neigh_parms_net(p), neigh_path, t->neigh_vars);
3099 if (!t->sysctl_header)
3100 goto free;
3101
3102 p->sysctl_table = t;
3103 return 0;
3104
3105free:
3106 kfree(t);
3107err:
3108 return -ENOBUFS;
3109}
3110EXPORT_SYMBOL(neigh_sysctl_register);
3111
3112void neigh_sysctl_unregister(struct neigh_parms *p)
3113{
3114 if (p->sysctl_table) {
3115 struct neigh_sysctl_table *t = p->sysctl_table;
3116 p->sysctl_table = NULL;
3117 unregister_net_sysctl_table(t->sysctl_header);
3118 kfree(t);
3119 }
3120}
3121EXPORT_SYMBOL(neigh_sysctl_unregister);
3122
3123#endif /* CONFIG_SYSCTL */
3124
3125static int __init neigh_init(void)
3126{
3127 rtnl_register(PF_UNSPEC, RTM_NEWNEIGH, neigh_add, NULL, NULL);
3128 rtnl_register(PF_UNSPEC, RTM_DELNEIGH, neigh_delete, NULL, NULL);
3129 rtnl_register(PF_UNSPEC, RTM_GETNEIGH, NULL, neigh_dump_info, NULL);
3130
3131 rtnl_register(PF_UNSPEC, RTM_GETNEIGHTBL, NULL, neightbl_dump_info,
3132 NULL);
3133 rtnl_register(PF_UNSPEC, RTM_SETNEIGHTBL, neightbl_set, NULL, NULL);
3134
3135 return 0;
3136}
3137
3138subsys_initcall(neigh_init);
3139
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Generic address resolution entity
4 *
5 * Authors:
6 * Pedro Roque <roque@di.fc.ul.pt>
7 * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
8 *
9 * Fixes:
10 * Vitaly E. Lavrov releasing NULL neighbor in neigh_add.
11 * Harald Welte Add neighbour cache statistics like rtstat
12 */
13
14#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
15
16#include <linux/slab.h>
17#include <linux/kmemleak.h>
18#include <linux/types.h>
19#include <linux/kernel.h>
20#include <linux/module.h>
21#include <linux/socket.h>
22#include <linux/netdevice.h>
23#include <linux/proc_fs.h>
24#ifdef CONFIG_SYSCTL
25#include <linux/sysctl.h>
26#endif
27#include <linux/times.h>
28#include <net/net_namespace.h>
29#include <net/neighbour.h>
30#include <net/arp.h>
31#include <net/dst.h>
32#include <net/sock.h>
33#include <net/netevent.h>
34#include <net/netlink.h>
35#include <linux/rtnetlink.h>
36#include <linux/random.h>
37#include <linux/string.h>
38#include <linux/log2.h>
39#include <linux/inetdevice.h>
40#include <net/addrconf.h>
41
42#include <trace/events/neigh.h>
43
44#define NEIGH_DEBUG 1
45#define neigh_dbg(level, fmt, ...) \
46do { \
47 if (level <= NEIGH_DEBUG) \
48 pr_debug(fmt, ##__VA_ARGS__); \
49} while (0)
50
51#define PNEIGH_HASHMASK 0xF
52
53static void neigh_timer_handler(struct timer_list *t);
54static void __neigh_notify(struct neighbour *n, int type, int flags,
55 u32 pid);
56static void neigh_update_notify(struct neighbour *neigh, u32 nlmsg_pid);
57static int pneigh_ifdown_and_unlock(struct neigh_table *tbl,
58 struct net_device *dev);
59
60#ifdef CONFIG_PROC_FS
61static const struct seq_operations neigh_stat_seq_ops;
62#endif
63
64/*
65 Neighbour hash table buckets are protected with rwlock tbl->lock.
66
67 - All the scans/updates to hash buckets MUST be made under this lock.
68 - NOTHING clever should be made under this lock: no callbacks
69 to protocol backends, no attempts to send something to network.
70 It will result in deadlocks, if backend/driver wants to use neighbour
71 cache.
72 - If the entry requires some non-trivial actions, increase
73 its reference count and release table lock.
74
75 Neighbour entries are protected:
76 - with reference count.
77 - with rwlock neigh->lock
78
79 Reference count prevents destruction.
80
81 neigh->lock mainly serializes ll address data and its validity state.
82 However, the same lock is used to protect another entry fields:
83 - timer
84 - resolution queue
85
86 Again, nothing clever shall be made under neigh->lock,
87 the most complicated procedure, which we allow is dev->hard_header.
88 It is supposed, that dev->hard_header is simplistic and does
89 not make callbacks to neighbour tables.
90 */
91
92static int neigh_blackhole(struct neighbour *neigh, struct sk_buff *skb)
93{
94 kfree_skb(skb);
95 return -ENETDOWN;
96}
97
98static void neigh_cleanup_and_release(struct neighbour *neigh)
99{
100 trace_neigh_cleanup_and_release(neigh, 0);
101 __neigh_notify(neigh, RTM_DELNEIGH, 0, 0);
102 call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, neigh);
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 ? get_random_u32_below(base) + (base >> 1) : 0;
115}
116EXPORT_SYMBOL(neigh_rand_reach_time);
117
118static void neigh_mark_dead(struct neighbour *n)
119{
120 n->dead = 1;
121 if (!list_empty(&n->gc_list)) {
122 list_del_init(&n->gc_list);
123 atomic_dec(&n->tbl->gc_entries);
124 }
125 if (!list_empty(&n->managed_list))
126 list_del_init(&n->managed_list);
127}
128
129static void neigh_update_gc_list(struct neighbour *n)
130{
131 bool on_gc_list, exempt_from_gc;
132
133 write_lock_bh(&n->tbl->lock);
134 write_lock(&n->lock);
135 if (n->dead)
136 goto out;
137
138 /* remove from the gc list if new state is permanent or if neighbor
139 * is externally learned; otherwise entry should be on the gc list
140 */
141 exempt_from_gc = n->nud_state & NUD_PERMANENT ||
142 n->flags & NTF_EXT_LEARNED;
143 on_gc_list = !list_empty(&n->gc_list);
144
145 if (exempt_from_gc && on_gc_list) {
146 list_del_init(&n->gc_list);
147 atomic_dec(&n->tbl->gc_entries);
148 } else if (!exempt_from_gc && !on_gc_list) {
149 /* add entries to the tail; cleaning removes from the front */
150 list_add_tail(&n->gc_list, &n->tbl->gc_list);
151 atomic_inc(&n->tbl->gc_entries);
152 }
153out:
154 write_unlock(&n->lock);
155 write_unlock_bh(&n->tbl->lock);
156}
157
158static void neigh_update_managed_list(struct neighbour *n)
159{
160 bool on_managed_list, add_to_managed;
161
162 write_lock_bh(&n->tbl->lock);
163 write_lock(&n->lock);
164 if (n->dead)
165 goto out;
166
167 add_to_managed = n->flags & NTF_MANAGED;
168 on_managed_list = !list_empty(&n->managed_list);
169
170 if (!add_to_managed && on_managed_list)
171 list_del_init(&n->managed_list);
172 else if (add_to_managed && !on_managed_list)
173 list_add_tail(&n->managed_list, &n->tbl->managed_list);
174out:
175 write_unlock(&n->lock);
176 write_unlock_bh(&n->tbl->lock);
177}
178
179static void neigh_update_flags(struct neighbour *neigh, u32 flags, int *notify,
180 bool *gc_update, bool *managed_update)
181{
182 u32 ndm_flags, old_flags = neigh->flags;
183
184 if (!(flags & NEIGH_UPDATE_F_ADMIN))
185 return;
186
187 ndm_flags = (flags & NEIGH_UPDATE_F_EXT_LEARNED) ? NTF_EXT_LEARNED : 0;
188 ndm_flags |= (flags & NEIGH_UPDATE_F_MANAGED) ? NTF_MANAGED : 0;
189
190 if ((old_flags ^ ndm_flags) & NTF_EXT_LEARNED) {
191 if (ndm_flags & NTF_EXT_LEARNED)
192 neigh->flags |= NTF_EXT_LEARNED;
193 else
194 neigh->flags &= ~NTF_EXT_LEARNED;
195 *notify = 1;
196 *gc_update = true;
197 }
198 if ((old_flags ^ ndm_flags) & NTF_MANAGED) {
199 if (ndm_flags & NTF_MANAGED)
200 neigh->flags |= NTF_MANAGED;
201 else
202 neigh->flags &= ~NTF_MANAGED;
203 *notify = 1;
204 *managed_update = true;
205 }
206}
207
208static bool neigh_del(struct neighbour *n, struct neighbour __rcu **np,
209 struct neigh_table *tbl)
210{
211 bool retval = false;
212
213 write_lock(&n->lock);
214 if (refcount_read(&n->refcnt) == 1) {
215 struct neighbour *neigh;
216
217 neigh = rcu_dereference_protected(n->next,
218 lockdep_is_held(&tbl->lock));
219 rcu_assign_pointer(*np, neigh);
220 neigh_mark_dead(n);
221 retval = true;
222 }
223 write_unlock(&n->lock);
224 if (retval)
225 neigh_cleanup_and_release(n);
226 return retval;
227}
228
229bool neigh_remove_one(struct neighbour *ndel, struct neigh_table *tbl)
230{
231 struct neigh_hash_table *nht;
232 void *pkey = ndel->primary_key;
233 u32 hash_val;
234 struct neighbour *n;
235 struct neighbour __rcu **np;
236
237 nht = rcu_dereference_protected(tbl->nht,
238 lockdep_is_held(&tbl->lock));
239 hash_val = tbl->hash(pkey, ndel->dev, nht->hash_rnd);
240 hash_val = hash_val >> (32 - nht->hash_shift);
241
242 np = &nht->hash_buckets[hash_val];
243 while ((n = rcu_dereference_protected(*np,
244 lockdep_is_held(&tbl->lock)))) {
245 if (n == ndel)
246 return neigh_del(n, np, tbl);
247 np = &n->next;
248 }
249 return false;
250}
251
252static int neigh_forced_gc(struct neigh_table *tbl)
253{
254 int max_clean = atomic_read(&tbl->gc_entries) -
255 READ_ONCE(tbl->gc_thresh2);
256 u64 tmax = ktime_get_ns() + NSEC_PER_MSEC;
257 unsigned long tref = jiffies - 5 * HZ;
258 struct neighbour *n, *tmp;
259 int shrunk = 0;
260 int loop = 0;
261
262 NEIGH_CACHE_STAT_INC(tbl, forced_gc_runs);
263
264 write_lock_bh(&tbl->lock);
265
266 list_for_each_entry_safe(n, tmp, &tbl->gc_list, gc_list) {
267 if (refcount_read(&n->refcnt) == 1) {
268 bool remove = false;
269
270 write_lock(&n->lock);
271 if ((n->nud_state == NUD_FAILED) ||
272 (n->nud_state == NUD_NOARP) ||
273 (tbl->is_multicast &&
274 tbl->is_multicast(n->primary_key)) ||
275 !time_in_range(n->updated, tref, jiffies))
276 remove = true;
277 write_unlock(&n->lock);
278
279 if (remove && neigh_remove_one(n, tbl))
280 shrunk++;
281 if (shrunk >= max_clean)
282 break;
283 if (++loop == 16) {
284 if (ktime_get_ns() > tmax)
285 goto unlock;
286 loop = 0;
287 }
288 }
289 }
290
291 WRITE_ONCE(tbl->last_flush, jiffies);
292unlock:
293 write_unlock_bh(&tbl->lock);
294
295 return shrunk;
296}
297
298static void neigh_add_timer(struct neighbour *n, unsigned long when)
299{
300 /* Use safe distance from the jiffies - LONG_MAX point while timer
301 * is running in DELAY/PROBE state but still show to user space
302 * large times in the past.
303 */
304 unsigned long mint = jiffies - (LONG_MAX - 86400 * HZ);
305
306 neigh_hold(n);
307 if (!time_in_range(n->confirmed, mint, jiffies))
308 n->confirmed = mint;
309 if (time_before(n->used, n->confirmed))
310 n->used = n->confirmed;
311 if (unlikely(mod_timer(&n->timer, when))) {
312 printk("NEIGH: BUG, double timer add, state is %x\n",
313 n->nud_state);
314 dump_stack();
315 }
316}
317
318static int neigh_del_timer(struct neighbour *n)
319{
320 if ((n->nud_state & NUD_IN_TIMER) &&
321 del_timer(&n->timer)) {
322 neigh_release(n);
323 return 1;
324 }
325 return 0;
326}
327
328static struct neigh_parms *neigh_get_dev_parms_rcu(struct net_device *dev,
329 int family)
330{
331 switch (family) {
332 case AF_INET:
333 return __in_dev_arp_parms_get_rcu(dev);
334 case AF_INET6:
335 return __in6_dev_nd_parms_get_rcu(dev);
336 }
337 return NULL;
338}
339
340static void neigh_parms_qlen_dec(struct net_device *dev, int family)
341{
342 struct neigh_parms *p;
343
344 rcu_read_lock();
345 p = neigh_get_dev_parms_rcu(dev, family);
346 if (p)
347 p->qlen--;
348 rcu_read_unlock();
349}
350
351static void pneigh_queue_purge(struct sk_buff_head *list, struct net *net,
352 int family)
353{
354 struct sk_buff_head tmp;
355 unsigned long flags;
356 struct sk_buff *skb;
357
358 skb_queue_head_init(&tmp);
359 spin_lock_irqsave(&list->lock, flags);
360 skb = skb_peek(list);
361 while (skb != NULL) {
362 struct sk_buff *skb_next = skb_peek_next(skb, list);
363 struct net_device *dev = skb->dev;
364
365 if (net == NULL || net_eq(dev_net(dev), net)) {
366 neigh_parms_qlen_dec(dev, family);
367 __skb_unlink(skb, list);
368 __skb_queue_tail(&tmp, skb);
369 }
370 skb = skb_next;
371 }
372 spin_unlock_irqrestore(&list->lock, flags);
373
374 while ((skb = __skb_dequeue(&tmp))) {
375 dev_put(skb->dev);
376 kfree_skb(skb);
377 }
378}
379
380static void neigh_flush_dev(struct neigh_table *tbl, struct net_device *dev,
381 bool skip_perm)
382{
383 int i;
384 struct neigh_hash_table *nht;
385
386 nht = rcu_dereference_protected(tbl->nht,
387 lockdep_is_held(&tbl->lock));
388
389 for (i = 0; i < (1 << nht->hash_shift); i++) {
390 struct neighbour *n;
391 struct neighbour __rcu **np = &nht->hash_buckets[i];
392
393 while ((n = rcu_dereference_protected(*np,
394 lockdep_is_held(&tbl->lock))) != NULL) {
395 if (dev && n->dev != dev) {
396 np = &n->next;
397 continue;
398 }
399 if (skip_perm && n->nud_state & NUD_PERMANENT) {
400 np = &n->next;
401 continue;
402 }
403 rcu_assign_pointer(*np,
404 rcu_dereference_protected(n->next,
405 lockdep_is_held(&tbl->lock)));
406 write_lock(&n->lock);
407 neigh_del_timer(n);
408 neigh_mark_dead(n);
409 if (refcount_read(&n->refcnt) != 1) {
410 /* The most unpleasant situation.
411 We must destroy neighbour entry,
412 but someone still uses it.
413
414 The destroy will be delayed until
415 the last user releases us, but
416 we must kill timers etc. and move
417 it to safe state.
418 */
419 __skb_queue_purge(&n->arp_queue);
420 n->arp_queue_len_bytes = 0;
421 WRITE_ONCE(n->output, neigh_blackhole);
422 if (n->nud_state & NUD_VALID)
423 n->nud_state = NUD_NOARP;
424 else
425 n->nud_state = NUD_NONE;
426 neigh_dbg(2, "neigh %p is stray\n", n);
427 }
428 write_unlock(&n->lock);
429 neigh_cleanup_and_release(n);
430 }
431 }
432}
433
434void neigh_changeaddr(struct neigh_table *tbl, struct net_device *dev)
435{
436 write_lock_bh(&tbl->lock);
437 neigh_flush_dev(tbl, dev, false);
438 write_unlock_bh(&tbl->lock);
439}
440EXPORT_SYMBOL(neigh_changeaddr);
441
442static int __neigh_ifdown(struct neigh_table *tbl, struct net_device *dev,
443 bool skip_perm)
444{
445 write_lock_bh(&tbl->lock);
446 neigh_flush_dev(tbl, dev, skip_perm);
447 pneigh_ifdown_and_unlock(tbl, dev);
448 pneigh_queue_purge(&tbl->proxy_queue, dev ? dev_net(dev) : NULL,
449 tbl->family);
450 if (skb_queue_empty_lockless(&tbl->proxy_queue))
451 del_timer_sync(&tbl->proxy_timer);
452 return 0;
453}
454
455int neigh_carrier_down(struct neigh_table *tbl, struct net_device *dev)
456{
457 __neigh_ifdown(tbl, dev, true);
458 return 0;
459}
460EXPORT_SYMBOL(neigh_carrier_down);
461
462int neigh_ifdown(struct neigh_table *tbl, struct net_device *dev)
463{
464 __neigh_ifdown(tbl, dev, false);
465 return 0;
466}
467EXPORT_SYMBOL(neigh_ifdown);
468
469static struct neighbour *neigh_alloc(struct neigh_table *tbl,
470 struct net_device *dev,
471 u32 flags, bool exempt_from_gc)
472{
473 struct neighbour *n = NULL;
474 unsigned long now = jiffies;
475 int entries, gc_thresh3;
476
477 if (exempt_from_gc)
478 goto do_alloc;
479
480 entries = atomic_inc_return(&tbl->gc_entries) - 1;
481 gc_thresh3 = READ_ONCE(tbl->gc_thresh3);
482 if (entries >= gc_thresh3 ||
483 (entries >= READ_ONCE(tbl->gc_thresh2) &&
484 time_after(now, READ_ONCE(tbl->last_flush) + 5 * HZ))) {
485 if (!neigh_forced_gc(tbl) && entries >= gc_thresh3) {
486 net_info_ratelimited("%s: neighbor table overflow!\n",
487 tbl->id);
488 NEIGH_CACHE_STAT_INC(tbl, table_fulls);
489 goto out_entries;
490 }
491 }
492
493do_alloc:
494 n = kzalloc(tbl->entry_size + dev->neigh_priv_len, GFP_ATOMIC);
495 if (!n)
496 goto out_entries;
497
498 __skb_queue_head_init(&n->arp_queue);
499 rwlock_init(&n->lock);
500 seqlock_init(&n->ha_lock);
501 n->updated = n->used = now;
502 n->nud_state = NUD_NONE;
503 n->output = neigh_blackhole;
504 n->flags = flags;
505 seqlock_init(&n->hh.hh_lock);
506 n->parms = neigh_parms_clone(&tbl->parms);
507 timer_setup(&n->timer, neigh_timer_handler, 0);
508
509 NEIGH_CACHE_STAT_INC(tbl, allocs);
510 n->tbl = tbl;
511 refcount_set(&n->refcnt, 1);
512 n->dead = 1;
513 INIT_LIST_HEAD(&n->gc_list);
514 INIT_LIST_HEAD(&n->managed_list);
515
516 atomic_inc(&tbl->entries);
517out:
518 return n;
519
520out_entries:
521 if (!exempt_from_gc)
522 atomic_dec(&tbl->gc_entries);
523 goto out;
524}
525
526static void neigh_get_hash_rnd(u32 *x)
527{
528 *x = get_random_u32() | 1;
529}
530
531static struct neigh_hash_table *neigh_hash_alloc(unsigned int shift)
532{
533 size_t size = (1 << shift) * sizeof(struct neighbour *);
534 struct neigh_hash_table *ret;
535 struct neighbour __rcu **buckets;
536 int i;
537
538 ret = kmalloc(sizeof(*ret), GFP_ATOMIC);
539 if (!ret)
540 return NULL;
541 if (size <= PAGE_SIZE) {
542 buckets = kzalloc(size, GFP_ATOMIC);
543 } else {
544 buckets = (struct neighbour __rcu **)
545 __get_free_pages(GFP_ATOMIC | __GFP_ZERO,
546 get_order(size));
547 kmemleak_alloc(buckets, size, 1, GFP_ATOMIC);
548 }
549 if (!buckets) {
550 kfree(ret);
551 return NULL;
552 }
553 ret->hash_buckets = buckets;
554 ret->hash_shift = shift;
555 for (i = 0; i < NEIGH_NUM_HASH_RND; i++)
556 neigh_get_hash_rnd(&ret->hash_rnd[i]);
557 return ret;
558}
559
560static void neigh_hash_free_rcu(struct rcu_head *head)
561{
562 struct neigh_hash_table *nht = container_of(head,
563 struct neigh_hash_table,
564 rcu);
565 size_t size = (1 << nht->hash_shift) * sizeof(struct neighbour *);
566 struct neighbour __rcu **buckets = nht->hash_buckets;
567
568 if (size <= PAGE_SIZE) {
569 kfree(buckets);
570 } else {
571 kmemleak_free(buckets);
572 free_pages((unsigned long)buckets, get_order(size));
573 }
574 kfree(nht);
575}
576
577static struct neigh_hash_table *neigh_hash_grow(struct neigh_table *tbl,
578 unsigned long new_shift)
579{
580 unsigned int i, hash;
581 struct neigh_hash_table *new_nht, *old_nht;
582
583 NEIGH_CACHE_STAT_INC(tbl, hash_grows);
584
585 old_nht = rcu_dereference_protected(tbl->nht,
586 lockdep_is_held(&tbl->lock));
587 new_nht = neigh_hash_alloc(new_shift);
588 if (!new_nht)
589 return old_nht;
590
591 for (i = 0; i < (1 << old_nht->hash_shift); i++) {
592 struct neighbour *n, *next;
593
594 for (n = rcu_dereference_protected(old_nht->hash_buckets[i],
595 lockdep_is_held(&tbl->lock));
596 n != NULL;
597 n = next) {
598 hash = tbl->hash(n->primary_key, n->dev,
599 new_nht->hash_rnd);
600
601 hash >>= (32 - new_nht->hash_shift);
602 next = rcu_dereference_protected(n->next,
603 lockdep_is_held(&tbl->lock));
604
605 rcu_assign_pointer(n->next,
606 rcu_dereference_protected(
607 new_nht->hash_buckets[hash],
608 lockdep_is_held(&tbl->lock)));
609 rcu_assign_pointer(new_nht->hash_buckets[hash], n);
610 }
611 }
612
613 rcu_assign_pointer(tbl->nht, new_nht);
614 call_rcu(&old_nht->rcu, neigh_hash_free_rcu);
615 return new_nht;
616}
617
618struct neighbour *neigh_lookup(struct neigh_table *tbl, const void *pkey,
619 struct net_device *dev)
620{
621 struct neighbour *n;
622
623 NEIGH_CACHE_STAT_INC(tbl, lookups);
624
625 rcu_read_lock();
626 n = __neigh_lookup_noref(tbl, pkey, dev);
627 if (n) {
628 if (!refcount_inc_not_zero(&n->refcnt))
629 n = NULL;
630 NEIGH_CACHE_STAT_INC(tbl, hits);
631 }
632
633 rcu_read_unlock();
634 return n;
635}
636EXPORT_SYMBOL(neigh_lookup);
637
638static struct neighbour *
639___neigh_create(struct neigh_table *tbl, const void *pkey,
640 struct net_device *dev, u32 flags,
641 bool exempt_from_gc, bool want_ref)
642{
643 u32 hash_val, key_len = tbl->key_len;
644 struct neighbour *n1, *rc, *n;
645 struct neigh_hash_table *nht;
646 int error;
647
648 n = neigh_alloc(tbl, dev, flags, exempt_from_gc);
649 trace_neigh_create(tbl, dev, pkey, n, exempt_from_gc);
650 if (!n) {
651 rc = ERR_PTR(-ENOBUFS);
652 goto out;
653 }
654
655 memcpy(n->primary_key, pkey, key_len);
656 n->dev = dev;
657 netdev_hold(dev, &n->dev_tracker, GFP_ATOMIC);
658
659 /* Protocol specific setup. */
660 if (tbl->constructor && (error = tbl->constructor(n)) < 0) {
661 rc = ERR_PTR(error);
662 goto out_neigh_release;
663 }
664
665 if (dev->netdev_ops->ndo_neigh_construct) {
666 error = dev->netdev_ops->ndo_neigh_construct(dev, n);
667 if (error < 0) {
668 rc = ERR_PTR(error);
669 goto out_neigh_release;
670 }
671 }
672
673 /* Device specific setup. */
674 if (n->parms->neigh_setup &&
675 (error = n->parms->neigh_setup(n)) < 0) {
676 rc = ERR_PTR(error);
677 goto out_neigh_release;
678 }
679
680 n->confirmed = jiffies - (NEIGH_VAR(n->parms, BASE_REACHABLE_TIME) << 1);
681
682 write_lock_bh(&tbl->lock);
683 nht = rcu_dereference_protected(tbl->nht,
684 lockdep_is_held(&tbl->lock));
685
686 if (atomic_read(&tbl->entries) > (1 << nht->hash_shift))
687 nht = neigh_hash_grow(tbl, nht->hash_shift + 1);
688
689 hash_val = tbl->hash(n->primary_key, dev, nht->hash_rnd) >> (32 - nht->hash_shift);
690
691 if (n->parms->dead) {
692 rc = ERR_PTR(-EINVAL);
693 goto out_tbl_unlock;
694 }
695
696 for (n1 = rcu_dereference_protected(nht->hash_buckets[hash_val],
697 lockdep_is_held(&tbl->lock));
698 n1 != NULL;
699 n1 = rcu_dereference_protected(n1->next,
700 lockdep_is_held(&tbl->lock))) {
701 if (dev == n1->dev && !memcmp(n1->primary_key, n->primary_key, key_len)) {
702 if (want_ref)
703 neigh_hold(n1);
704 rc = n1;
705 goto out_tbl_unlock;
706 }
707 }
708
709 n->dead = 0;
710 if (!exempt_from_gc)
711 list_add_tail(&n->gc_list, &n->tbl->gc_list);
712 if (n->flags & NTF_MANAGED)
713 list_add_tail(&n->managed_list, &n->tbl->managed_list);
714 if (want_ref)
715 neigh_hold(n);
716 rcu_assign_pointer(n->next,
717 rcu_dereference_protected(nht->hash_buckets[hash_val],
718 lockdep_is_held(&tbl->lock)));
719 rcu_assign_pointer(nht->hash_buckets[hash_val], n);
720 write_unlock_bh(&tbl->lock);
721 neigh_dbg(2, "neigh %p is created\n", n);
722 rc = n;
723out:
724 return rc;
725out_tbl_unlock:
726 write_unlock_bh(&tbl->lock);
727out_neigh_release:
728 if (!exempt_from_gc)
729 atomic_dec(&tbl->gc_entries);
730 neigh_release(n);
731 goto out;
732}
733
734struct neighbour *__neigh_create(struct neigh_table *tbl, const void *pkey,
735 struct net_device *dev, bool want_ref)
736{
737 return ___neigh_create(tbl, pkey, dev, 0, false, want_ref);
738}
739EXPORT_SYMBOL(__neigh_create);
740
741static u32 pneigh_hash(const void *pkey, unsigned int key_len)
742{
743 u32 hash_val = *(u32 *)(pkey + key_len - 4);
744 hash_val ^= (hash_val >> 16);
745 hash_val ^= hash_val >> 8;
746 hash_val ^= hash_val >> 4;
747 hash_val &= PNEIGH_HASHMASK;
748 return hash_val;
749}
750
751static struct pneigh_entry *__pneigh_lookup_1(struct pneigh_entry *n,
752 struct net *net,
753 const void *pkey,
754 unsigned int key_len,
755 struct net_device *dev)
756{
757 while (n) {
758 if (!memcmp(n->key, pkey, key_len) &&
759 net_eq(pneigh_net(n), net) &&
760 (n->dev == dev || !n->dev))
761 return n;
762 n = n->next;
763 }
764 return NULL;
765}
766
767struct pneigh_entry *__pneigh_lookup(struct neigh_table *tbl,
768 struct net *net, const void *pkey, struct net_device *dev)
769{
770 unsigned int key_len = tbl->key_len;
771 u32 hash_val = pneigh_hash(pkey, key_len);
772
773 return __pneigh_lookup_1(tbl->phash_buckets[hash_val],
774 net, pkey, key_len, dev);
775}
776EXPORT_SYMBOL_GPL(__pneigh_lookup);
777
778struct pneigh_entry * pneigh_lookup(struct neigh_table *tbl,
779 struct net *net, const void *pkey,
780 struct net_device *dev, int creat)
781{
782 struct pneigh_entry *n;
783 unsigned int key_len = tbl->key_len;
784 u32 hash_val = pneigh_hash(pkey, key_len);
785
786 read_lock_bh(&tbl->lock);
787 n = __pneigh_lookup_1(tbl->phash_buckets[hash_val],
788 net, pkey, key_len, dev);
789 read_unlock_bh(&tbl->lock);
790
791 if (n || !creat)
792 goto out;
793
794 ASSERT_RTNL();
795
796 n = kzalloc(sizeof(*n) + key_len, GFP_KERNEL);
797 if (!n)
798 goto out;
799
800 write_pnet(&n->net, net);
801 memcpy(n->key, pkey, key_len);
802 n->dev = dev;
803 netdev_hold(dev, &n->dev_tracker, GFP_KERNEL);
804
805 if (tbl->pconstructor && tbl->pconstructor(n)) {
806 netdev_put(dev, &n->dev_tracker);
807 kfree(n);
808 n = NULL;
809 goto out;
810 }
811
812 write_lock_bh(&tbl->lock);
813 n->next = tbl->phash_buckets[hash_val];
814 tbl->phash_buckets[hash_val] = n;
815 write_unlock_bh(&tbl->lock);
816out:
817 return n;
818}
819EXPORT_SYMBOL(pneigh_lookup);
820
821
822int pneigh_delete(struct neigh_table *tbl, struct net *net, const void *pkey,
823 struct net_device *dev)
824{
825 struct pneigh_entry *n, **np;
826 unsigned int key_len = tbl->key_len;
827 u32 hash_val = pneigh_hash(pkey, key_len);
828
829 write_lock_bh(&tbl->lock);
830 for (np = &tbl->phash_buckets[hash_val]; (n = *np) != NULL;
831 np = &n->next) {
832 if (!memcmp(n->key, pkey, key_len) && n->dev == dev &&
833 net_eq(pneigh_net(n), net)) {
834 *np = n->next;
835 write_unlock_bh(&tbl->lock);
836 if (tbl->pdestructor)
837 tbl->pdestructor(n);
838 netdev_put(n->dev, &n->dev_tracker);
839 kfree(n);
840 return 0;
841 }
842 }
843 write_unlock_bh(&tbl->lock);
844 return -ENOENT;
845}
846
847static int pneigh_ifdown_and_unlock(struct neigh_table *tbl,
848 struct net_device *dev)
849{
850 struct pneigh_entry *n, **np, *freelist = NULL;
851 u32 h;
852
853 for (h = 0; h <= PNEIGH_HASHMASK; h++) {
854 np = &tbl->phash_buckets[h];
855 while ((n = *np) != NULL) {
856 if (!dev || n->dev == dev) {
857 *np = n->next;
858 n->next = freelist;
859 freelist = n;
860 continue;
861 }
862 np = &n->next;
863 }
864 }
865 write_unlock_bh(&tbl->lock);
866 while ((n = freelist)) {
867 freelist = n->next;
868 n->next = NULL;
869 if (tbl->pdestructor)
870 tbl->pdestructor(n);
871 netdev_put(n->dev, &n->dev_tracker);
872 kfree(n);
873 }
874 return -ENOENT;
875}
876
877static void neigh_parms_destroy(struct neigh_parms *parms);
878
879static inline void neigh_parms_put(struct neigh_parms *parms)
880{
881 if (refcount_dec_and_test(&parms->refcnt))
882 neigh_parms_destroy(parms);
883}
884
885/*
886 * neighbour must already be out of the table;
887 *
888 */
889void neigh_destroy(struct neighbour *neigh)
890{
891 struct net_device *dev = neigh->dev;
892
893 NEIGH_CACHE_STAT_INC(neigh->tbl, destroys);
894
895 if (!neigh->dead) {
896 pr_warn("Destroying alive neighbour %p\n", neigh);
897 dump_stack();
898 return;
899 }
900
901 if (neigh_del_timer(neigh))
902 pr_warn("Impossible event\n");
903
904 write_lock_bh(&neigh->lock);
905 __skb_queue_purge(&neigh->arp_queue);
906 write_unlock_bh(&neigh->lock);
907 neigh->arp_queue_len_bytes = 0;
908
909 if (dev->netdev_ops->ndo_neigh_destroy)
910 dev->netdev_ops->ndo_neigh_destroy(dev, neigh);
911
912 netdev_put(dev, &neigh->dev_tracker);
913 neigh_parms_put(neigh->parms);
914
915 neigh_dbg(2, "neigh %p is destroyed\n", neigh);
916
917 atomic_dec(&neigh->tbl->entries);
918 kfree_rcu(neigh, rcu);
919}
920EXPORT_SYMBOL(neigh_destroy);
921
922/* Neighbour state is suspicious;
923 disable fast path.
924
925 Called with write_locked neigh.
926 */
927static void neigh_suspect(struct neighbour *neigh)
928{
929 neigh_dbg(2, "neigh %p is suspected\n", neigh);
930
931 WRITE_ONCE(neigh->output, neigh->ops->output);
932}
933
934/* Neighbour state is OK;
935 enable fast path.
936
937 Called with write_locked neigh.
938 */
939static void neigh_connect(struct neighbour *neigh)
940{
941 neigh_dbg(2, "neigh %p is connected\n", neigh);
942
943 WRITE_ONCE(neigh->output, neigh->ops->connected_output);
944}
945
946static void neigh_periodic_work(struct work_struct *work)
947{
948 struct neigh_table *tbl = container_of(work, struct neigh_table, gc_work.work);
949 struct neighbour *n;
950 struct neighbour __rcu **np;
951 unsigned int i;
952 struct neigh_hash_table *nht;
953
954 NEIGH_CACHE_STAT_INC(tbl, periodic_gc_runs);
955
956 write_lock_bh(&tbl->lock);
957 nht = rcu_dereference_protected(tbl->nht,
958 lockdep_is_held(&tbl->lock));
959
960 /*
961 * periodically recompute ReachableTime from random function
962 */
963
964 if (time_after(jiffies, tbl->last_rand + 300 * HZ)) {
965 struct neigh_parms *p;
966
967 WRITE_ONCE(tbl->last_rand, jiffies);
968 list_for_each_entry(p, &tbl->parms_list, list)
969 p->reachable_time =
970 neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME));
971 }
972
973 if (atomic_read(&tbl->entries) < READ_ONCE(tbl->gc_thresh1))
974 goto out;
975
976 for (i = 0 ; i < (1 << nht->hash_shift); i++) {
977 np = &nht->hash_buckets[i];
978
979 while ((n = rcu_dereference_protected(*np,
980 lockdep_is_held(&tbl->lock))) != NULL) {
981 unsigned int state;
982
983 write_lock(&n->lock);
984
985 state = n->nud_state;
986 if ((state & (NUD_PERMANENT | NUD_IN_TIMER)) ||
987 (n->flags & NTF_EXT_LEARNED)) {
988 write_unlock(&n->lock);
989 goto next_elt;
990 }
991
992 if (time_before(n->used, n->confirmed) &&
993 time_is_before_eq_jiffies(n->confirmed))
994 n->used = n->confirmed;
995
996 if (refcount_read(&n->refcnt) == 1 &&
997 (state == NUD_FAILED ||
998 !time_in_range_open(jiffies, n->used,
999 n->used + NEIGH_VAR(n->parms, GC_STALETIME)))) {
1000 rcu_assign_pointer(*np,
1001 rcu_dereference_protected(n->next,
1002 lockdep_is_held(&tbl->lock)));
1003 neigh_mark_dead(n);
1004 write_unlock(&n->lock);
1005 neigh_cleanup_and_release(n);
1006 continue;
1007 }
1008 write_unlock(&n->lock);
1009
1010next_elt:
1011 np = &n->next;
1012 }
1013 /*
1014 * It's fine to release lock here, even if hash table
1015 * grows while we are preempted.
1016 */
1017 write_unlock_bh(&tbl->lock);
1018 cond_resched();
1019 write_lock_bh(&tbl->lock);
1020 nht = rcu_dereference_protected(tbl->nht,
1021 lockdep_is_held(&tbl->lock));
1022 }
1023out:
1024 /* Cycle through all hash buckets every BASE_REACHABLE_TIME/2 ticks.
1025 * ARP entry timeouts range from 1/2 BASE_REACHABLE_TIME to 3/2
1026 * BASE_REACHABLE_TIME.
1027 */
1028 queue_delayed_work(system_power_efficient_wq, &tbl->gc_work,
1029 NEIGH_VAR(&tbl->parms, BASE_REACHABLE_TIME) >> 1);
1030 write_unlock_bh(&tbl->lock);
1031}
1032
1033static __inline__ int neigh_max_probes(struct neighbour *n)
1034{
1035 struct neigh_parms *p = n->parms;
1036 return NEIGH_VAR(p, UCAST_PROBES) + NEIGH_VAR(p, APP_PROBES) +
1037 (n->nud_state & NUD_PROBE ? NEIGH_VAR(p, MCAST_REPROBES) :
1038 NEIGH_VAR(p, MCAST_PROBES));
1039}
1040
1041static void neigh_invalidate(struct neighbour *neigh)
1042 __releases(neigh->lock)
1043 __acquires(neigh->lock)
1044{
1045 struct sk_buff *skb;
1046
1047 NEIGH_CACHE_STAT_INC(neigh->tbl, res_failed);
1048 neigh_dbg(2, "neigh %p is failed\n", neigh);
1049 neigh->updated = jiffies;
1050
1051 /* It is very thin place. report_unreachable is very complicated
1052 routine. Particularly, it can hit the same neighbour entry!
1053
1054 So that, we try to be accurate and avoid dead loop. --ANK
1055 */
1056 while (neigh->nud_state == NUD_FAILED &&
1057 (skb = __skb_dequeue(&neigh->arp_queue)) != NULL) {
1058 write_unlock(&neigh->lock);
1059 neigh->ops->error_report(neigh, skb);
1060 write_lock(&neigh->lock);
1061 }
1062 __skb_queue_purge(&neigh->arp_queue);
1063 neigh->arp_queue_len_bytes = 0;
1064}
1065
1066static void neigh_probe(struct neighbour *neigh)
1067 __releases(neigh->lock)
1068{
1069 struct sk_buff *skb = skb_peek_tail(&neigh->arp_queue);
1070 /* keep skb alive even if arp_queue overflows */
1071 if (skb)
1072 skb = skb_clone(skb, GFP_ATOMIC);
1073 write_unlock(&neigh->lock);
1074 if (neigh->ops->solicit)
1075 neigh->ops->solicit(neigh, skb);
1076 atomic_inc(&neigh->probes);
1077 consume_skb(skb);
1078}
1079
1080/* Called when a timer expires for a neighbour entry. */
1081
1082static void neigh_timer_handler(struct timer_list *t)
1083{
1084 unsigned long now, next;
1085 struct neighbour *neigh = from_timer(neigh, t, timer);
1086 unsigned int state;
1087 int notify = 0;
1088
1089 write_lock(&neigh->lock);
1090
1091 state = neigh->nud_state;
1092 now = jiffies;
1093 next = now + HZ;
1094
1095 if (!(state & NUD_IN_TIMER))
1096 goto out;
1097
1098 if (state & NUD_REACHABLE) {
1099 if (time_before_eq(now,
1100 neigh->confirmed + neigh->parms->reachable_time)) {
1101 neigh_dbg(2, "neigh %p is still alive\n", neigh);
1102 next = neigh->confirmed + neigh->parms->reachable_time;
1103 } else if (time_before_eq(now,
1104 neigh->used +
1105 NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME))) {
1106 neigh_dbg(2, "neigh %p is delayed\n", neigh);
1107 WRITE_ONCE(neigh->nud_state, NUD_DELAY);
1108 neigh->updated = jiffies;
1109 neigh_suspect(neigh);
1110 next = now + NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME);
1111 } else {
1112 neigh_dbg(2, "neigh %p is suspected\n", neigh);
1113 WRITE_ONCE(neigh->nud_state, NUD_STALE);
1114 neigh->updated = jiffies;
1115 neigh_suspect(neigh);
1116 notify = 1;
1117 }
1118 } else if (state & NUD_DELAY) {
1119 if (time_before_eq(now,
1120 neigh->confirmed +
1121 NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME))) {
1122 neigh_dbg(2, "neigh %p is now reachable\n", neigh);
1123 WRITE_ONCE(neigh->nud_state, NUD_REACHABLE);
1124 neigh->updated = jiffies;
1125 neigh_connect(neigh);
1126 notify = 1;
1127 next = neigh->confirmed + neigh->parms->reachable_time;
1128 } else {
1129 neigh_dbg(2, "neigh %p is probed\n", neigh);
1130 WRITE_ONCE(neigh->nud_state, NUD_PROBE);
1131 neigh->updated = jiffies;
1132 atomic_set(&neigh->probes, 0);
1133 notify = 1;
1134 next = now + max(NEIGH_VAR(neigh->parms, RETRANS_TIME),
1135 HZ/100);
1136 }
1137 } else {
1138 /* NUD_PROBE|NUD_INCOMPLETE */
1139 next = now + max(NEIGH_VAR(neigh->parms, RETRANS_TIME), HZ/100);
1140 }
1141
1142 if ((neigh->nud_state & (NUD_INCOMPLETE | NUD_PROBE)) &&
1143 atomic_read(&neigh->probes) >= neigh_max_probes(neigh)) {
1144 WRITE_ONCE(neigh->nud_state, NUD_FAILED);
1145 notify = 1;
1146 neigh_invalidate(neigh);
1147 goto out;
1148 }
1149
1150 if (neigh->nud_state & NUD_IN_TIMER) {
1151 if (time_before(next, jiffies + HZ/100))
1152 next = jiffies + HZ/100;
1153 if (!mod_timer(&neigh->timer, next))
1154 neigh_hold(neigh);
1155 }
1156 if (neigh->nud_state & (NUD_INCOMPLETE | NUD_PROBE)) {
1157 neigh_probe(neigh);
1158 } else {
1159out:
1160 write_unlock(&neigh->lock);
1161 }
1162
1163 if (notify)
1164 neigh_update_notify(neigh, 0);
1165
1166 trace_neigh_timer_handler(neigh, 0);
1167
1168 neigh_release(neigh);
1169}
1170
1171int __neigh_event_send(struct neighbour *neigh, struct sk_buff *skb,
1172 const bool immediate_ok)
1173{
1174 int rc;
1175 bool immediate_probe = false;
1176
1177 write_lock_bh(&neigh->lock);
1178
1179 rc = 0;
1180 if (neigh->nud_state & (NUD_CONNECTED | NUD_DELAY | NUD_PROBE))
1181 goto out_unlock_bh;
1182 if (neigh->dead)
1183 goto out_dead;
1184
1185 if (!(neigh->nud_state & (NUD_STALE | NUD_INCOMPLETE))) {
1186 if (NEIGH_VAR(neigh->parms, MCAST_PROBES) +
1187 NEIGH_VAR(neigh->parms, APP_PROBES)) {
1188 unsigned long next, now = jiffies;
1189
1190 atomic_set(&neigh->probes,
1191 NEIGH_VAR(neigh->parms, UCAST_PROBES));
1192 neigh_del_timer(neigh);
1193 WRITE_ONCE(neigh->nud_state, NUD_INCOMPLETE);
1194 neigh->updated = now;
1195 if (!immediate_ok) {
1196 next = now + 1;
1197 } else {
1198 immediate_probe = true;
1199 next = now + max(NEIGH_VAR(neigh->parms,
1200 RETRANS_TIME),
1201 HZ / 100);
1202 }
1203 neigh_add_timer(neigh, next);
1204 } else {
1205 WRITE_ONCE(neigh->nud_state, NUD_FAILED);
1206 neigh->updated = jiffies;
1207 write_unlock_bh(&neigh->lock);
1208
1209 kfree_skb_reason(skb, SKB_DROP_REASON_NEIGH_FAILED);
1210 return 1;
1211 }
1212 } else if (neigh->nud_state & NUD_STALE) {
1213 neigh_dbg(2, "neigh %p is delayed\n", neigh);
1214 neigh_del_timer(neigh);
1215 WRITE_ONCE(neigh->nud_state, NUD_DELAY);
1216 neigh->updated = jiffies;
1217 neigh_add_timer(neigh, jiffies +
1218 NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME));
1219 }
1220
1221 if (neigh->nud_state == NUD_INCOMPLETE) {
1222 if (skb) {
1223 while (neigh->arp_queue_len_bytes + skb->truesize >
1224 NEIGH_VAR(neigh->parms, QUEUE_LEN_BYTES)) {
1225 struct sk_buff *buff;
1226
1227 buff = __skb_dequeue(&neigh->arp_queue);
1228 if (!buff)
1229 break;
1230 neigh->arp_queue_len_bytes -= buff->truesize;
1231 kfree_skb_reason(buff, SKB_DROP_REASON_NEIGH_QUEUEFULL);
1232 NEIGH_CACHE_STAT_INC(neigh->tbl, unres_discards);
1233 }
1234 skb_dst_force(skb);
1235 __skb_queue_tail(&neigh->arp_queue, skb);
1236 neigh->arp_queue_len_bytes += skb->truesize;
1237 }
1238 rc = 1;
1239 }
1240out_unlock_bh:
1241 if (immediate_probe)
1242 neigh_probe(neigh);
1243 else
1244 write_unlock(&neigh->lock);
1245 local_bh_enable();
1246 trace_neigh_event_send_done(neigh, rc);
1247 return rc;
1248
1249out_dead:
1250 if (neigh->nud_state & NUD_STALE)
1251 goto out_unlock_bh;
1252 write_unlock_bh(&neigh->lock);
1253 kfree_skb_reason(skb, SKB_DROP_REASON_NEIGH_DEAD);
1254 trace_neigh_event_send_dead(neigh, 1);
1255 return 1;
1256}
1257EXPORT_SYMBOL(__neigh_event_send);
1258
1259static void neigh_update_hhs(struct neighbour *neigh)
1260{
1261 struct hh_cache *hh;
1262 void (*update)(struct hh_cache*, const struct net_device*, const unsigned char *)
1263 = NULL;
1264
1265 if (neigh->dev->header_ops)
1266 update = neigh->dev->header_ops->cache_update;
1267
1268 if (update) {
1269 hh = &neigh->hh;
1270 if (READ_ONCE(hh->hh_len)) {
1271 write_seqlock_bh(&hh->hh_lock);
1272 update(hh, neigh->dev, neigh->ha);
1273 write_sequnlock_bh(&hh->hh_lock);
1274 }
1275 }
1276}
1277
1278/* Generic update routine.
1279 -- lladdr is new lladdr or NULL, if it is not supplied.
1280 -- new is new state.
1281 -- flags
1282 NEIGH_UPDATE_F_OVERRIDE allows to override existing lladdr,
1283 if it is different.
1284 NEIGH_UPDATE_F_WEAK_OVERRIDE will suspect existing "connected"
1285 lladdr instead of overriding it
1286 if it is different.
1287 NEIGH_UPDATE_F_ADMIN means that the change is administrative.
1288 NEIGH_UPDATE_F_USE means that the entry is user triggered.
1289 NEIGH_UPDATE_F_MANAGED means that the entry will be auto-refreshed.
1290 NEIGH_UPDATE_F_OVERRIDE_ISROUTER allows to override existing
1291 NTF_ROUTER flag.
1292 NEIGH_UPDATE_F_ISROUTER indicates if the neighbour is known as
1293 a router.
1294
1295 Caller MUST hold reference count on the entry.
1296 */
1297static int __neigh_update(struct neighbour *neigh, const u8 *lladdr,
1298 u8 new, u32 flags, u32 nlmsg_pid,
1299 struct netlink_ext_ack *extack)
1300{
1301 bool gc_update = false, managed_update = false;
1302 int update_isrouter = 0;
1303 struct net_device *dev;
1304 int err, notify = 0;
1305 u8 old;
1306
1307 trace_neigh_update(neigh, lladdr, new, flags, nlmsg_pid);
1308
1309 write_lock_bh(&neigh->lock);
1310
1311 dev = neigh->dev;
1312 old = neigh->nud_state;
1313 err = -EPERM;
1314
1315 if (neigh->dead) {
1316 NL_SET_ERR_MSG(extack, "Neighbor entry is now dead");
1317 new = old;
1318 goto out;
1319 }
1320 if (!(flags & NEIGH_UPDATE_F_ADMIN) &&
1321 (old & (NUD_NOARP | NUD_PERMANENT)))
1322 goto out;
1323
1324 neigh_update_flags(neigh, flags, ¬ify, &gc_update, &managed_update);
1325 if (flags & (NEIGH_UPDATE_F_USE | NEIGH_UPDATE_F_MANAGED)) {
1326 new = old & ~NUD_PERMANENT;
1327 WRITE_ONCE(neigh->nud_state, new);
1328 err = 0;
1329 goto out;
1330 }
1331
1332 if (!(new & NUD_VALID)) {
1333 neigh_del_timer(neigh);
1334 if (old & NUD_CONNECTED)
1335 neigh_suspect(neigh);
1336 WRITE_ONCE(neigh->nud_state, new);
1337 err = 0;
1338 notify = old & NUD_VALID;
1339 if ((old & (NUD_INCOMPLETE | NUD_PROBE)) &&
1340 (new & NUD_FAILED)) {
1341 neigh_invalidate(neigh);
1342 notify = 1;
1343 }
1344 goto out;
1345 }
1346
1347 /* Compare new lladdr with cached one */
1348 if (!dev->addr_len) {
1349 /* First case: device needs no address. */
1350 lladdr = neigh->ha;
1351 } else if (lladdr) {
1352 /* The second case: if something is already cached
1353 and a new address is proposed:
1354 - compare new & old
1355 - if they are different, check override flag
1356 */
1357 if ((old & NUD_VALID) &&
1358 !memcmp(lladdr, neigh->ha, dev->addr_len))
1359 lladdr = neigh->ha;
1360 } else {
1361 /* No address is supplied; if we know something,
1362 use it, otherwise discard the request.
1363 */
1364 err = -EINVAL;
1365 if (!(old & NUD_VALID)) {
1366 NL_SET_ERR_MSG(extack, "No link layer address given");
1367 goto out;
1368 }
1369 lladdr = neigh->ha;
1370 }
1371
1372 /* Update confirmed timestamp for neighbour entry after we
1373 * received ARP packet even if it doesn't change IP to MAC binding.
1374 */
1375 if (new & NUD_CONNECTED)
1376 neigh->confirmed = jiffies;
1377
1378 /* If entry was valid and address is not changed,
1379 do not change entry state, if new one is STALE.
1380 */
1381 err = 0;
1382 update_isrouter = flags & NEIGH_UPDATE_F_OVERRIDE_ISROUTER;
1383 if (old & NUD_VALID) {
1384 if (lladdr != neigh->ha && !(flags & NEIGH_UPDATE_F_OVERRIDE)) {
1385 update_isrouter = 0;
1386 if ((flags & NEIGH_UPDATE_F_WEAK_OVERRIDE) &&
1387 (old & NUD_CONNECTED)) {
1388 lladdr = neigh->ha;
1389 new = NUD_STALE;
1390 } else
1391 goto out;
1392 } else {
1393 if (lladdr == neigh->ha && new == NUD_STALE &&
1394 !(flags & NEIGH_UPDATE_F_ADMIN))
1395 new = old;
1396 }
1397 }
1398
1399 /* Update timestamp only once we know we will make a change to the
1400 * neighbour entry. Otherwise we risk to move the locktime window with
1401 * noop updates and ignore relevant ARP updates.
1402 */
1403 if (new != old || lladdr != neigh->ha)
1404 neigh->updated = jiffies;
1405
1406 if (new != old) {
1407 neigh_del_timer(neigh);
1408 if (new & NUD_PROBE)
1409 atomic_set(&neigh->probes, 0);
1410 if (new & NUD_IN_TIMER)
1411 neigh_add_timer(neigh, (jiffies +
1412 ((new & NUD_REACHABLE) ?
1413 neigh->parms->reachable_time :
1414 0)));
1415 WRITE_ONCE(neigh->nud_state, new);
1416 notify = 1;
1417 }
1418
1419 if (lladdr != neigh->ha) {
1420 write_seqlock(&neigh->ha_lock);
1421 memcpy(&neigh->ha, lladdr, dev->addr_len);
1422 write_sequnlock(&neigh->ha_lock);
1423 neigh_update_hhs(neigh);
1424 if (!(new & NUD_CONNECTED))
1425 neigh->confirmed = jiffies -
1426 (NEIGH_VAR(neigh->parms, BASE_REACHABLE_TIME) << 1);
1427 notify = 1;
1428 }
1429 if (new == old)
1430 goto out;
1431 if (new & NUD_CONNECTED)
1432 neigh_connect(neigh);
1433 else
1434 neigh_suspect(neigh);
1435 if (!(old & NUD_VALID)) {
1436 struct sk_buff *skb;
1437
1438 /* Again: avoid dead loop if something went wrong */
1439
1440 while (neigh->nud_state & NUD_VALID &&
1441 (skb = __skb_dequeue(&neigh->arp_queue)) != NULL) {
1442 struct dst_entry *dst = skb_dst(skb);
1443 struct neighbour *n2, *n1 = neigh;
1444 write_unlock_bh(&neigh->lock);
1445
1446 rcu_read_lock();
1447
1448 /* Why not just use 'neigh' as-is? The problem is that
1449 * things such as shaper, eql, and sch_teql can end up
1450 * using alternative, different, neigh objects to output
1451 * the packet in the output path. So what we need to do
1452 * here is re-lookup the top-level neigh in the path so
1453 * we can reinject the packet there.
1454 */
1455 n2 = NULL;
1456 if (dst && dst->obsolete != DST_OBSOLETE_DEAD) {
1457 n2 = dst_neigh_lookup_skb(dst, skb);
1458 if (n2)
1459 n1 = n2;
1460 }
1461 READ_ONCE(n1->output)(n1, skb);
1462 if (n2)
1463 neigh_release(n2);
1464 rcu_read_unlock();
1465
1466 write_lock_bh(&neigh->lock);
1467 }
1468 __skb_queue_purge(&neigh->arp_queue);
1469 neigh->arp_queue_len_bytes = 0;
1470 }
1471out:
1472 if (update_isrouter)
1473 neigh_update_is_router(neigh, flags, ¬ify);
1474 write_unlock_bh(&neigh->lock);
1475 if (((new ^ old) & NUD_PERMANENT) || gc_update)
1476 neigh_update_gc_list(neigh);
1477 if (managed_update)
1478 neigh_update_managed_list(neigh);
1479 if (notify)
1480 neigh_update_notify(neigh, nlmsg_pid);
1481 trace_neigh_update_done(neigh, err);
1482 return err;
1483}
1484
1485int neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new,
1486 u32 flags, u32 nlmsg_pid)
1487{
1488 return __neigh_update(neigh, lladdr, new, flags, nlmsg_pid, NULL);
1489}
1490EXPORT_SYMBOL(neigh_update);
1491
1492/* Update the neigh to listen temporarily for probe responses, even if it is
1493 * in a NUD_FAILED state. The caller has to hold neigh->lock for writing.
1494 */
1495void __neigh_set_probe_once(struct neighbour *neigh)
1496{
1497 if (neigh->dead)
1498 return;
1499 neigh->updated = jiffies;
1500 if (!(neigh->nud_state & NUD_FAILED))
1501 return;
1502 WRITE_ONCE(neigh->nud_state, NUD_INCOMPLETE);
1503 atomic_set(&neigh->probes, neigh_max_probes(neigh));
1504 neigh_add_timer(neigh,
1505 jiffies + max(NEIGH_VAR(neigh->parms, RETRANS_TIME),
1506 HZ/100));
1507}
1508EXPORT_SYMBOL(__neigh_set_probe_once);
1509
1510struct neighbour *neigh_event_ns(struct neigh_table *tbl,
1511 u8 *lladdr, void *saddr,
1512 struct net_device *dev)
1513{
1514 struct neighbour *neigh = __neigh_lookup(tbl, saddr, dev,
1515 lladdr || !dev->addr_len);
1516 if (neigh)
1517 neigh_update(neigh, lladdr, NUD_STALE,
1518 NEIGH_UPDATE_F_OVERRIDE, 0);
1519 return neigh;
1520}
1521EXPORT_SYMBOL(neigh_event_ns);
1522
1523/* called with read_lock_bh(&n->lock); */
1524static void neigh_hh_init(struct neighbour *n)
1525{
1526 struct net_device *dev = n->dev;
1527 __be16 prot = n->tbl->protocol;
1528 struct hh_cache *hh = &n->hh;
1529
1530 write_lock_bh(&n->lock);
1531
1532 /* Only one thread can come in here and initialize the
1533 * hh_cache entry.
1534 */
1535 if (!hh->hh_len)
1536 dev->header_ops->cache(n, hh, prot);
1537
1538 write_unlock_bh(&n->lock);
1539}
1540
1541/* Slow and careful. */
1542
1543int neigh_resolve_output(struct neighbour *neigh, struct sk_buff *skb)
1544{
1545 int rc = 0;
1546
1547 if (!neigh_event_send(neigh, skb)) {
1548 int err;
1549 struct net_device *dev = neigh->dev;
1550 unsigned int seq;
1551
1552 if (dev->header_ops->cache && !READ_ONCE(neigh->hh.hh_len))
1553 neigh_hh_init(neigh);
1554
1555 do {
1556 __skb_pull(skb, skb_network_offset(skb));
1557 seq = read_seqbegin(&neigh->ha_lock);
1558 err = dev_hard_header(skb, dev, ntohs(skb->protocol),
1559 neigh->ha, NULL, skb->len);
1560 } while (read_seqretry(&neigh->ha_lock, seq));
1561
1562 if (err >= 0)
1563 rc = dev_queue_xmit(skb);
1564 else
1565 goto out_kfree_skb;
1566 }
1567out:
1568 return rc;
1569out_kfree_skb:
1570 rc = -EINVAL;
1571 kfree_skb(skb);
1572 goto out;
1573}
1574EXPORT_SYMBOL(neigh_resolve_output);
1575
1576/* As fast as possible without hh cache */
1577
1578int neigh_connected_output(struct neighbour *neigh, struct sk_buff *skb)
1579{
1580 struct net_device *dev = neigh->dev;
1581 unsigned int seq;
1582 int err;
1583
1584 do {
1585 __skb_pull(skb, skb_network_offset(skb));
1586 seq = read_seqbegin(&neigh->ha_lock);
1587 err = dev_hard_header(skb, dev, ntohs(skb->protocol),
1588 neigh->ha, NULL, skb->len);
1589 } while (read_seqretry(&neigh->ha_lock, seq));
1590
1591 if (err >= 0)
1592 err = dev_queue_xmit(skb);
1593 else {
1594 err = -EINVAL;
1595 kfree_skb(skb);
1596 }
1597 return err;
1598}
1599EXPORT_SYMBOL(neigh_connected_output);
1600
1601int neigh_direct_output(struct neighbour *neigh, struct sk_buff *skb)
1602{
1603 return dev_queue_xmit(skb);
1604}
1605EXPORT_SYMBOL(neigh_direct_output);
1606
1607static void neigh_managed_work(struct work_struct *work)
1608{
1609 struct neigh_table *tbl = container_of(work, struct neigh_table,
1610 managed_work.work);
1611 struct neighbour *neigh;
1612
1613 write_lock_bh(&tbl->lock);
1614 list_for_each_entry(neigh, &tbl->managed_list, managed_list)
1615 neigh_event_send_probe(neigh, NULL, false);
1616 queue_delayed_work(system_power_efficient_wq, &tbl->managed_work,
1617 NEIGH_VAR(&tbl->parms, INTERVAL_PROBE_TIME_MS));
1618 write_unlock_bh(&tbl->lock);
1619}
1620
1621static void neigh_proxy_process(struct timer_list *t)
1622{
1623 struct neigh_table *tbl = from_timer(tbl, t, proxy_timer);
1624 long sched_next = 0;
1625 unsigned long now = jiffies;
1626 struct sk_buff *skb, *n;
1627
1628 spin_lock(&tbl->proxy_queue.lock);
1629
1630 skb_queue_walk_safe(&tbl->proxy_queue, skb, n) {
1631 long tdif = NEIGH_CB(skb)->sched_next - now;
1632
1633 if (tdif <= 0) {
1634 struct net_device *dev = skb->dev;
1635
1636 neigh_parms_qlen_dec(dev, tbl->family);
1637 __skb_unlink(skb, &tbl->proxy_queue);
1638
1639 if (tbl->proxy_redo && netif_running(dev)) {
1640 rcu_read_lock();
1641 tbl->proxy_redo(skb);
1642 rcu_read_unlock();
1643 } else {
1644 kfree_skb(skb);
1645 }
1646
1647 dev_put(dev);
1648 } else if (!sched_next || tdif < sched_next)
1649 sched_next = tdif;
1650 }
1651 del_timer(&tbl->proxy_timer);
1652 if (sched_next)
1653 mod_timer(&tbl->proxy_timer, jiffies + sched_next);
1654 spin_unlock(&tbl->proxy_queue.lock);
1655}
1656
1657static unsigned long neigh_proxy_delay(struct neigh_parms *p)
1658{
1659 /* If proxy_delay is zero, do not call get_random_u32_below()
1660 * as it is undefined behavior.
1661 */
1662 unsigned long proxy_delay = NEIGH_VAR(p, PROXY_DELAY);
1663
1664 return proxy_delay ?
1665 jiffies + get_random_u32_below(proxy_delay) : jiffies;
1666}
1667
1668void pneigh_enqueue(struct neigh_table *tbl, struct neigh_parms *p,
1669 struct sk_buff *skb)
1670{
1671 unsigned long sched_next = neigh_proxy_delay(p);
1672
1673 if (p->qlen > NEIGH_VAR(p, PROXY_QLEN)) {
1674 kfree_skb(skb);
1675 return;
1676 }
1677
1678 NEIGH_CB(skb)->sched_next = sched_next;
1679 NEIGH_CB(skb)->flags |= LOCALLY_ENQUEUED;
1680
1681 spin_lock(&tbl->proxy_queue.lock);
1682 if (del_timer(&tbl->proxy_timer)) {
1683 if (time_before(tbl->proxy_timer.expires, sched_next))
1684 sched_next = tbl->proxy_timer.expires;
1685 }
1686 skb_dst_drop(skb);
1687 dev_hold(skb->dev);
1688 __skb_queue_tail(&tbl->proxy_queue, skb);
1689 p->qlen++;
1690 mod_timer(&tbl->proxy_timer, sched_next);
1691 spin_unlock(&tbl->proxy_queue.lock);
1692}
1693EXPORT_SYMBOL(pneigh_enqueue);
1694
1695static inline struct neigh_parms *lookup_neigh_parms(struct neigh_table *tbl,
1696 struct net *net, int ifindex)
1697{
1698 struct neigh_parms *p;
1699
1700 list_for_each_entry(p, &tbl->parms_list, list) {
1701 if ((p->dev && p->dev->ifindex == ifindex && net_eq(neigh_parms_net(p), net)) ||
1702 (!p->dev && !ifindex && net_eq(net, &init_net)))
1703 return p;
1704 }
1705
1706 return NULL;
1707}
1708
1709struct neigh_parms *neigh_parms_alloc(struct net_device *dev,
1710 struct neigh_table *tbl)
1711{
1712 struct neigh_parms *p;
1713 struct net *net = dev_net(dev);
1714 const struct net_device_ops *ops = dev->netdev_ops;
1715
1716 p = kmemdup(&tbl->parms, sizeof(*p), GFP_KERNEL);
1717 if (p) {
1718 p->tbl = tbl;
1719 refcount_set(&p->refcnt, 1);
1720 p->reachable_time =
1721 neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME));
1722 p->qlen = 0;
1723 netdev_hold(dev, &p->dev_tracker, GFP_KERNEL);
1724 p->dev = dev;
1725 write_pnet(&p->net, net);
1726 p->sysctl_table = NULL;
1727
1728 if (ops->ndo_neigh_setup && ops->ndo_neigh_setup(dev, p)) {
1729 netdev_put(dev, &p->dev_tracker);
1730 kfree(p);
1731 return NULL;
1732 }
1733
1734 write_lock_bh(&tbl->lock);
1735 list_add(&p->list, &tbl->parms.list);
1736 write_unlock_bh(&tbl->lock);
1737
1738 neigh_parms_data_state_cleanall(p);
1739 }
1740 return p;
1741}
1742EXPORT_SYMBOL(neigh_parms_alloc);
1743
1744static void neigh_rcu_free_parms(struct rcu_head *head)
1745{
1746 struct neigh_parms *parms =
1747 container_of(head, struct neigh_parms, rcu_head);
1748
1749 neigh_parms_put(parms);
1750}
1751
1752void neigh_parms_release(struct neigh_table *tbl, struct neigh_parms *parms)
1753{
1754 if (!parms || parms == &tbl->parms)
1755 return;
1756 write_lock_bh(&tbl->lock);
1757 list_del(&parms->list);
1758 parms->dead = 1;
1759 write_unlock_bh(&tbl->lock);
1760 netdev_put(parms->dev, &parms->dev_tracker);
1761 call_rcu(&parms->rcu_head, neigh_rcu_free_parms);
1762}
1763EXPORT_SYMBOL(neigh_parms_release);
1764
1765static void neigh_parms_destroy(struct neigh_parms *parms)
1766{
1767 kfree(parms);
1768}
1769
1770static struct lock_class_key neigh_table_proxy_queue_class;
1771
1772static struct neigh_table *neigh_tables[NEIGH_NR_TABLES] __read_mostly;
1773
1774void neigh_table_init(int index, struct neigh_table *tbl)
1775{
1776 unsigned long now = jiffies;
1777 unsigned long phsize;
1778
1779 INIT_LIST_HEAD(&tbl->parms_list);
1780 INIT_LIST_HEAD(&tbl->gc_list);
1781 INIT_LIST_HEAD(&tbl->managed_list);
1782
1783 list_add(&tbl->parms.list, &tbl->parms_list);
1784 write_pnet(&tbl->parms.net, &init_net);
1785 refcount_set(&tbl->parms.refcnt, 1);
1786 tbl->parms.reachable_time =
1787 neigh_rand_reach_time(NEIGH_VAR(&tbl->parms, BASE_REACHABLE_TIME));
1788 tbl->parms.qlen = 0;
1789
1790 tbl->stats = alloc_percpu(struct neigh_statistics);
1791 if (!tbl->stats)
1792 panic("cannot create neighbour cache statistics");
1793
1794#ifdef CONFIG_PROC_FS
1795 if (!proc_create_seq_data(tbl->id, 0, init_net.proc_net_stat,
1796 &neigh_stat_seq_ops, tbl))
1797 panic("cannot create neighbour proc dir entry");
1798#endif
1799
1800 RCU_INIT_POINTER(tbl->nht, neigh_hash_alloc(3));
1801
1802 phsize = (PNEIGH_HASHMASK + 1) * sizeof(struct pneigh_entry *);
1803 tbl->phash_buckets = kzalloc(phsize, GFP_KERNEL);
1804
1805 if (!tbl->nht || !tbl->phash_buckets)
1806 panic("cannot allocate neighbour cache hashes");
1807
1808 if (!tbl->entry_size)
1809 tbl->entry_size = ALIGN(offsetof(struct neighbour, primary_key) +
1810 tbl->key_len, NEIGH_PRIV_ALIGN);
1811 else
1812 WARN_ON(tbl->entry_size % NEIGH_PRIV_ALIGN);
1813
1814 rwlock_init(&tbl->lock);
1815
1816 INIT_DEFERRABLE_WORK(&tbl->gc_work, neigh_periodic_work);
1817 queue_delayed_work(system_power_efficient_wq, &tbl->gc_work,
1818 tbl->parms.reachable_time);
1819 INIT_DEFERRABLE_WORK(&tbl->managed_work, neigh_managed_work);
1820 queue_delayed_work(system_power_efficient_wq, &tbl->managed_work, 0);
1821
1822 timer_setup(&tbl->proxy_timer, neigh_proxy_process, 0);
1823 skb_queue_head_init_class(&tbl->proxy_queue,
1824 &neigh_table_proxy_queue_class);
1825
1826 tbl->last_flush = now;
1827 tbl->last_rand = now + tbl->parms.reachable_time * 20;
1828
1829 neigh_tables[index] = tbl;
1830}
1831EXPORT_SYMBOL(neigh_table_init);
1832
1833int neigh_table_clear(int index, struct neigh_table *tbl)
1834{
1835 neigh_tables[index] = NULL;
1836 /* It is not clean... Fix it to unload IPv6 module safely */
1837 cancel_delayed_work_sync(&tbl->managed_work);
1838 cancel_delayed_work_sync(&tbl->gc_work);
1839 del_timer_sync(&tbl->proxy_timer);
1840 pneigh_queue_purge(&tbl->proxy_queue, NULL, tbl->family);
1841 neigh_ifdown(tbl, NULL);
1842 if (atomic_read(&tbl->entries))
1843 pr_crit("neighbour leakage\n");
1844
1845 call_rcu(&rcu_dereference_protected(tbl->nht, 1)->rcu,
1846 neigh_hash_free_rcu);
1847 tbl->nht = NULL;
1848
1849 kfree(tbl->phash_buckets);
1850 tbl->phash_buckets = NULL;
1851
1852 remove_proc_entry(tbl->id, init_net.proc_net_stat);
1853
1854 free_percpu(tbl->stats);
1855 tbl->stats = NULL;
1856
1857 return 0;
1858}
1859EXPORT_SYMBOL(neigh_table_clear);
1860
1861static struct neigh_table *neigh_find_table(int family)
1862{
1863 struct neigh_table *tbl = NULL;
1864
1865 switch (family) {
1866 case AF_INET:
1867 tbl = neigh_tables[NEIGH_ARP_TABLE];
1868 break;
1869 case AF_INET6:
1870 tbl = neigh_tables[NEIGH_ND_TABLE];
1871 break;
1872 }
1873
1874 return tbl;
1875}
1876
1877const struct nla_policy nda_policy[NDA_MAX+1] = {
1878 [NDA_UNSPEC] = { .strict_start_type = NDA_NH_ID },
1879 [NDA_DST] = { .type = NLA_BINARY, .len = MAX_ADDR_LEN },
1880 [NDA_LLADDR] = { .type = NLA_BINARY, .len = MAX_ADDR_LEN },
1881 [NDA_CACHEINFO] = { .len = sizeof(struct nda_cacheinfo) },
1882 [NDA_PROBES] = { .type = NLA_U32 },
1883 [NDA_VLAN] = { .type = NLA_U16 },
1884 [NDA_PORT] = { .type = NLA_U16 },
1885 [NDA_VNI] = { .type = NLA_U32 },
1886 [NDA_IFINDEX] = { .type = NLA_U32 },
1887 [NDA_MASTER] = { .type = NLA_U32 },
1888 [NDA_PROTOCOL] = { .type = NLA_U8 },
1889 [NDA_NH_ID] = { .type = NLA_U32 },
1890 [NDA_FLAGS_EXT] = NLA_POLICY_MASK(NLA_U32, NTF_EXT_MASK),
1891 [NDA_FDB_EXT_ATTRS] = { .type = NLA_NESTED },
1892};
1893
1894static int neigh_delete(struct sk_buff *skb, struct nlmsghdr *nlh,
1895 struct netlink_ext_ack *extack)
1896{
1897 struct net *net = sock_net(skb->sk);
1898 struct ndmsg *ndm;
1899 struct nlattr *dst_attr;
1900 struct neigh_table *tbl;
1901 struct neighbour *neigh;
1902 struct net_device *dev = NULL;
1903 int err = -EINVAL;
1904
1905 ASSERT_RTNL();
1906 if (nlmsg_len(nlh) < sizeof(*ndm))
1907 goto out;
1908
1909 dst_attr = nlmsg_find_attr(nlh, sizeof(*ndm), NDA_DST);
1910 if (!dst_attr) {
1911 NL_SET_ERR_MSG(extack, "Network address not specified");
1912 goto out;
1913 }
1914
1915 ndm = nlmsg_data(nlh);
1916 if (ndm->ndm_ifindex) {
1917 dev = __dev_get_by_index(net, ndm->ndm_ifindex);
1918 if (dev == NULL) {
1919 err = -ENODEV;
1920 goto out;
1921 }
1922 }
1923
1924 tbl = neigh_find_table(ndm->ndm_family);
1925 if (tbl == NULL)
1926 return -EAFNOSUPPORT;
1927
1928 if (nla_len(dst_attr) < (int)tbl->key_len) {
1929 NL_SET_ERR_MSG(extack, "Invalid network address");
1930 goto out;
1931 }
1932
1933 if (ndm->ndm_flags & NTF_PROXY) {
1934 err = pneigh_delete(tbl, net, nla_data(dst_attr), dev);
1935 goto out;
1936 }
1937
1938 if (dev == NULL)
1939 goto out;
1940
1941 neigh = neigh_lookup(tbl, nla_data(dst_attr), dev);
1942 if (neigh == NULL) {
1943 err = -ENOENT;
1944 goto out;
1945 }
1946
1947 err = __neigh_update(neigh, NULL, NUD_FAILED,
1948 NEIGH_UPDATE_F_OVERRIDE | NEIGH_UPDATE_F_ADMIN,
1949 NETLINK_CB(skb).portid, extack);
1950 write_lock_bh(&tbl->lock);
1951 neigh_release(neigh);
1952 neigh_remove_one(neigh, tbl);
1953 write_unlock_bh(&tbl->lock);
1954
1955out:
1956 return err;
1957}
1958
1959static int neigh_add(struct sk_buff *skb, struct nlmsghdr *nlh,
1960 struct netlink_ext_ack *extack)
1961{
1962 int flags = NEIGH_UPDATE_F_ADMIN | NEIGH_UPDATE_F_OVERRIDE |
1963 NEIGH_UPDATE_F_OVERRIDE_ISROUTER;
1964 struct net *net = sock_net(skb->sk);
1965 struct ndmsg *ndm;
1966 struct nlattr *tb[NDA_MAX+1];
1967 struct neigh_table *tbl;
1968 struct net_device *dev = NULL;
1969 struct neighbour *neigh;
1970 void *dst, *lladdr;
1971 u8 protocol = 0;
1972 u32 ndm_flags;
1973 int err;
1974
1975 ASSERT_RTNL();
1976 err = nlmsg_parse_deprecated(nlh, sizeof(*ndm), tb, NDA_MAX,
1977 nda_policy, extack);
1978 if (err < 0)
1979 goto out;
1980
1981 err = -EINVAL;
1982 if (!tb[NDA_DST]) {
1983 NL_SET_ERR_MSG(extack, "Network address not specified");
1984 goto out;
1985 }
1986
1987 ndm = nlmsg_data(nlh);
1988 ndm_flags = ndm->ndm_flags;
1989 if (tb[NDA_FLAGS_EXT]) {
1990 u32 ext = nla_get_u32(tb[NDA_FLAGS_EXT]);
1991
1992 BUILD_BUG_ON(sizeof(neigh->flags) * BITS_PER_BYTE <
1993 (sizeof(ndm->ndm_flags) * BITS_PER_BYTE +
1994 hweight32(NTF_EXT_MASK)));
1995 ndm_flags |= (ext << NTF_EXT_SHIFT);
1996 }
1997 if (ndm->ndm_ifindex) {
1998 dev = __dev_get_by_index(net, ndm->ndm_ifindex);
1999 if (dev == NULL) {
2000 err = -ENODEV;
2001 goto out;
2002 }
2003
2004 if (tb[NDA_LLADDR] && nla_len(tb[NDA_LLADDR]) < dev->addr_len) {
2005 NL_SET_ERR_MSG(extack, "Invalid link address");
2006 goto out;
2007 }
2008 }
2009
2010 tbl = neigh_find_table(ndm->ndm_family);
2011 if (tbl == NULL)
2012 return -EAFNOSUPPORT;
2013
2014 if (nla_len(tb[NDA_DST]) < (int)tbl->key_len) {
2015 NL_SET_ERR_MSG(extack, "Invalid network address");
2016 goto out;
2017 }
2018
2019 dst = nla_data(tb[NDA_DST]);
2020 lladdr = tb[NDA_LLADDR] ? nla_data(tb[NDA_LLADDR]) : NULL;
2021
2022 if (tb[NDA_PROTOCOL])
2023 protocol = nla_get_u8(tb[NDA_PROTOCOL]);
2024 if (ndm_flags & NTF_PROXY) {
2025 struct pneigh_entry *pn;
2026
2027 if (ndm_flags & NTF_MANAGED) {
2028 NL_SET_ERR_MSG(extack, "Invalid NTF_* flag combination");
2029 goto out;
2030 }
2031
2032 err = -ENOBUFS;
2033 pn = pneigh_lookup(tbl, net, dst, dev, 1);
2034 if (pn) {
2035 pn->flags = ndm_flags;
2036 if (protocol)
2037 pn->protocol = protocol;
2038 err = 0;
2039 }
2040 goto out;
2041 }
2042
2043 if (!dev) {
2044 NL_SET_ERR_MSG(extack, "Device not specified");
2045 goto out;
2046 }
2047
2048 if (tbl->allow_add && !tbl->allow_add(dev, extack)) {
2049 err = -EINVAL;
2050 goto out;
2051 }
2052
2053 neigh = neigh_lookup(tbl, dst, dev);
2054 if (neigh == NULL) {
2055 bool ndm_permanent = ndm->ndm_state & NUD_PERMANENT;
2056 bool exempt_from_gc = ndm_permanent ||
2057 ndm_flags & NTF_EXT_LEARNED;
2058
2059 if (!(nlh->nlmsg_flags & NLM_F_CREATE)) {
2060 err = -ENOENT;
2061 goto out;
2062 }
2063 if (ndm_permanent && (ndm_flags & NTF_MANAGED)) {
2064 NL_SET_ERR_MSG(extack, "Invalid NTF_* flag for permanent entry");
2065 err = -EINVAL;
2066 goto out;
2067 }
2068
2069 neigh = ___neigh_create(tbl, dst, dev,
2070 ndm_flags &
2071 (NTF_EXT_LEARNED | NTF_MANAGED),
2072 exempt_from_gc, true);
2073 if (IS_ERR(neigh)) {
2074 err = PTR_ERR(neigh);
2075 goto out;
2076 }
2077 } else {
2078 if (nlh->nlmsg_flags & NLM_F_EXCL) {
2079 err = -EEXIST;
2080 neigh_release(neigh);
2081 goto out;
2082 }
2083
2084 if (!(nlh->nlmsg_flags & NLM_F_REPLACE))
2085 flags &= ~(NEIGH_UPDATE_F_OVERRIDE |
2086 NEIGH_UPDATE_F_OVERRIDE_ISROUTER);
2087 }
2088
2089 if (protocol)
2090 neigh->protocol = protocol;
2091 if (ndm_flags & NTF_EXT_LEARNED)
2092 flags |= NEIGH_UPDATE_F_EXT_LEARNED;
2093 if (ndm_flags & NTF_ROUTER)
2094 flags |= NEIGH_UPDATE_F_ISROUTER;
2095 if (ndm_flags & NTF_MANAGED)
2096 flags |= NEIGH_UPDATE_F_MANAGED;
2097 if (ndm_flags & NTF_USE)
2098 flags |= NEIGH_UPDATE_F_USE;
2099
2100 err = __neigh_update(neigh, lladdr, ndm->ndm_state, flags,
2101 NETLINK_CB(skb).portid, extack);
2102 if (!err && ndm_flags & (NTF_USE | NTF_MANAGED)) {
2103 neigh_event_send(neigh, NULL);
2104 err = 0;
2105 }
2106 neigh_release(neigh);
2107out:
2108 return err;
2109}
2110
2111static int neightbl_fill_parms(struct sk_buff *skb, struct neigh_parms *parms)
2112{
2113 struct nlattr *nest;
2114
2115 nest = nla_nest_start_noflag(skb, NDTA_PARMS);
2116 if (nest == NULL)
2117 return -ENOBUFS;
2118
2119 if ((parms->dev &&
2120 nla_put_u32(skb, NDTPA_IFINDEX, parms->dev->ifindex)) ||
2121 nla_put_u32(skb, NDTPA_REFCNT, refcount_read(&parms->refcnt)) ||
2122 nla_put_u32(skb, NDTPA_QUEUE_LENBYTES,
2123 NEIGH_VAR(parms, QUEUE_LEN_BYTES)) ||
2124 /* approximative value for deprecated QUEUE_LEN (in packets) */
2125 nla_put_u32(skb, NDTPA_QUEUE_LEN,
2126 NEIGH_VAR(parms, QUEUE_LEN_BYTES) / SKB_TRUESIZE(ETH_FRAME_LEN)) ||
2127 nla_put_u32(skb, NDTPA_PROXY_QLEN, NEIGH_VAR(parms, PROXY_QLEN)) ||
2128 nla_put_u32(skb, NDTPA_APP_PROBES, NEIGH_VAR(parms, APP_PROBES)) ||
2129 nla_put_u32(skb, NDTPA_UCAST_PROBES,
2130 NEIGH_VAR(parms, UCAST_PROBES)) ||
2131 nla_put_u32(skb, NDTPA_MCAST_PROBES,
2132 NEIGH_VAR(parms, MCAST_PROBES)) ||
2133 nla_put_u32(skb, NDTPA_MCAST_REPROBES,
2134 NEIGH_VAR(parms, MCAST_REPROBES)) ||
2135 nla_put_msecs(skb, NDTPA_REACHABLE_TIME, parms->reachable_time,
2136 NDTPA_PAD) ||
2137 nla_put_msecs(skb, NDTPA_BASE_REACHABLE_TIME,
2138 NEIGH_VAR(parms, BASE_REACHABLE_TIME), NDTPA_PAD) ||
2139 nla_put_msecs(skb, NDTPA_GC_STALETIME,
2140 NEIGH_VAR(parms, GC_STALETIME), NDTPA_PAD) ||
2141 nla_put_msecs(skb, NDTPA_DELAY_PROBE_TIME,
2142 NEIGH_VAR(parms, DELAY_PROBE_TIME), NDTPA_PAD) ||
2143 nla_put_msecs(skb, NDTPA_RETRANS_TIME,
2144 NEIGH_VAR(parms, RETRANS_TIME), NDTPA_PAD) ||
2145 nla_put_msecs(skb, NDTPA_ANYCAST_DELAY,
2146 NEIGH_VAR(parms, ANYCAST_DELAY), NDTPA_PAD) ||
2147 nla_put_msecs(skb, NDTPA_PROXY_DELAY,
2148 NEIGH_VAR(parms, PROXY_DELAY), NDTPA_PAD) ||
2149 nla_put_msecs(skb, NDTPA_LOCKTIME,
2150 NEIGH_VAR(parms, LOCKTIME), NDTPA_PAD) ||
2151 nla_put_msecs(skb, NDTPA_INTERVAL_PROBE_TIME_MS,
2152 NEIGH_VAR(parms, INTERVAL_PROBE_TIME_MS), NDTPA_PAD))
2153 goto nla_put_failure;
2154 return nla_nest_end(skb, nest);
2155
2156nla_put_failure:
2157 nla_nest_cancel(skb, nest);
2158 return -EMSGSIZE;
2159}
2160
2161static int neightbl_fill_info(struct sk_buff *skb, struct neigh_table *tbl,
2162 u32 pid, u32 seq, int type, int flags)
2163{
2164 struct nlmsghdr *nlh;
2165 struct ndtmsg *ndtmsg;
2166
2167 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndtmsg), flags);
2168 if (nlh == NULL)
2169 return -EMSGSIZE;
2170
2171 ndtmsg = nlmsg_data(nlh);
2172
2173 read_lock_bh(&tbl->lock);
2174 ndtmsg->ndtm_family = tbl->family;
2175 ndtmsg->ndtm_pad1 = 0;
2176 ndtmsg->ndtm_pad2 = 0;
2177
2178 if (nla_put_string(skb, NDTA_NAME, tbl->id) ||
2179 nla_put_msecs(skb, NDTA_GC_INTERVAL, READ_ONCE(tbl->gc_interval),
2180 NDTA_PAD) ||
2181 nla_put_u32(skb, NDTA_THRESH1, READ_ONCE(tbl->gc_thresh1)) ||
2182 nla_put_u32(skb, NDTA_THRESH2, READ_ONCE(tbl->gc_thresh2)) ||
2183 nla_put_u32(skb, NDTA_THRESH3, READ_ONCE(tbl->gc_thresh3)))
2184 goto nla_put_failure;
2185 {
2186 unsigned long now = jiffies;
2187 long flush_delta = now - READ_ONCE(tbl->last_flush);
2188 long rand_delta = now - READ_ONCE(tbl->last_rand);
2189 struct neigh_hash_table *nht;
2190 struct ndt_config ndc = {
2191 .ndtc_key_len = tbl->key_len,
2192 .ndtc_entry_size = tbl->entry_size,
2193 .ndtc_entries = atomic_read(&tbl->entries),
2194 .ndtc_last_flush = jiffies_to_msecs(flush_delta),
2195 .ndtc_last_rand = jiffies_to_msecs(rand_delta),
2196 .ndtc_proxy_qlen = READ_ONCE(tbl->proxy_queue.qlen),
2197 };
2198
2199 rcu_read_lock();
2200 nht = rcu_dereference(tbl->nht);
2201 ndc.ndtc_hash_rnd = nht->hash_rnd[0];
2202 ndc.ndtc_hash_mask = ((1 << nht->hash_shift) - 1);
2203 rcu_read_unlock();
2204
2205 if (nla_put(skb, NDTA_CONFIG, sizeof(ndc), &ndc))
2206 goto nla_put_failure;
2207 }
2208
2209 {
2210 int cpu;
2211 struct ndt_stats ndst;
2212
2213 memset(&ndst, 0, sizeof(ndst));
2214
2215 for_each_possible_cpu(cpu) {
2216 struct neigh_statistics *st;
2217
2218 st = per_cpu_ptr(tbl->stats, cpu);
2219 ndst.ndts_allocs += READ_ONCE(st->allocs);
2220 ndst.ndts_destroys += READ_ONCE(st->destroys);
2221 ndst.ndts_hash_grows += READ_ONCE(st->hash_grows);
2222 ndst.ndts_res_failed += READ_ONCE(st->res_failed);
2223 ndst.ndts_lookups += READ_ONCE(st->lookups);
2224 ndst.ndts_hits += READ_ONCE(st->hits);
2225 ndst.ndts_rcv_probes_mcast += READ_ONCE(st->rcv_probes_mcast);
2226 ndst.ndts_rcv_probes_ucast += READ_ONCE(st->rcv_probes_ucast);
2227 ndst.ndts_periodic_gc_runs += READ_ONCE(st->periodic_gc_runs);
2228 ndst.ndts_forced_gc_runs += READ_ONCE(st->forced_gc_runs);
2229 ndst.ndts_table_fulls += READ_ONCE(st->table_fulls);
2230 }
2231
2232 if (nla_put_64bit(skb, NDTA_STATS, sizeof(ndst), &ndst,
2233 NDTA_PAD))
2234 goto nla_put_failure;
2235 }
2236
2237 BUG_ON(tbl->parms.dev);
2238 if (neightbl_fill_parms(skb, &tbl->parms) < 0)
2239 goto nla_put_failure;
2240
2241 read_unlock_bh(&tbl->lock);
2242 nlmsg_end(skb, nlh);
2243 return 0;
2244
2245nla_put_failure:
2246 read_unlock_bh(&tbl->lock);
2247 nlmsg_cancel(skb, nlh);
2248 return -EMSGSIZE;
2249}
2250
2251static int neightbl_fill_param_info(struct sk_buff *skb,
2252 struct neigh_table *tbl,
2253 struct neigh_parms *parms,
2254 u32 pid, u32 seq, int type,
2255 unsigned int flags)
2256{
2257 struct ndtmsg *ndtmsg;
2258 struct nlmsghdr *nlh;
2259
2260 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndtmsg), flags);
2261 if (nlh == NULL)
2262 return -EMSGSIZE;
2263
2264 ndtmsg = nlmsg_data(nlh);
2265
2266 read_lock_bh(&tbl->lock);
2267 ndtmsg->ndtm_family = tbl->family;
2268 ndtmsg->ndtm_pad1 = 0;
2269 ndtmsg->ndtm_pad2 = 0;
2270
2271 if (nla_put_string(skb, NDTA_NAME, tbl->id) < 0 ||
2272 neightbl_fill_parms(skb, parms) < 0)
2273 goto errout;
2274
2275 read_unlock_bh(&tbl->lock);
2276 nlmsg_end(skb, nlh);
2277 return 0;
2278errout:
2279 read_unlock_bh(&tbl->lock);
2280 nlmsg_cancel(skb, nlh);
2281 return -EMSGSIZE;
2282}
2283
2284static const struct nla_policy nl_neightbl_policy[NDTA_MAX+1] = {
2285 [NDTA_NAME] = { .type = NLA_STRING },
2286 [NDTA_THRESH1] = { .type = NLA_U32 },
2287 [NDTA_THRESH2] = { .type = NLA_U32 },
2288 [NDTA_THRESH3] = { .type = NLA_U32 },
2289 [NDTA_GC_INTERVAL] = { .type = NLA_U64 },
2290 [NDTA_PARMS] = { .type = NLA_NESTED },
2291};
2292
2293static const struct nla_policy nl_ntbl_parm_policy[NDTPA_MAX+1] = {
2294 [NDTPA_IFINDEX] = { .type = NLA_U32 },
2295 [NDTPA_QUEUE_LEN] = { .type = NLA_U32 },
2296 [NDTPA_PROXY_QLEN] = { .type = NLA_U32 },
2297 [NDTPA_APP_PROBES] = { .type = NLA_U32 },
2298 [NDTPA_UCAST_PROBES] = { .type = NLA_U32 },
2299 [NDTPA_MCAST_PROBES] = { .type = NLA_U32 },
2300 [NDTPA_MCAST_REPROBES] = { .type = NLA_U32 },
2301 [NDTPA_BASE_REACHABLE_TIME] = { .type = NLA_U64 },
2302 [NDTPA_GC_STALETIME] = { .type = NLA_U64 },
2303 [NDTPA_DELAY_PROBE_TIME] = { .type = NLA_U64 },
2304 [NDTPA_RETRANS_TIME] = { .type = NLA_U64 },
2305 [NDTPA_ANYCAST_DELAY] = { .type = NLA_U64 },
2306 [NDTPA_PROXY_DELAY] = { .type = NLA_U64 },
2307 [NDTPA_LOCKTIME] = { .type = NLA_U64 },
2308 [NDTPA_INTERVAL_PROBE_TIME_MS] = { .type = NLA_U64, .min = 1 },
2309};
2310
2311static int neightbl_set(struct sk_buff *skb, struct nlmsghdr *nlh,
2312 struct netlink_ext_ack *extack)
2313{
2314 struct net *net = sock_net(skb->sk);
2315 struct neigh_table *tbl;
2316 struct ndtmsg *ndtmsg;
2317 struct nlattr *tb[NDTA_MAX+1];
2318 bool found = false;
2319 int err, tidx;
2320
2321 err = nlmsg_parse_deprecated(nlh, sizeof(*ndtmsg), tb, NDTA_MAX,
2322 nl_neightbl_policy, extack);
2323 if (err < 0)
2324 goto errout;
2325
2326 if (tb[NDTA_NAME] == NULL) {
2327 err = -EINVAL;
2328 goto errout;
2329 }
2330
2331 ndtmsg = nlmsg_data(nlh);
2332
2333 for (tidx = 0; tidx < NEIGH_NR_TABLES; tidx++) {
2334 tbl = neigh_tables[tidx];
2335 if (!tbl)
2336 continue;
2337 if (ndtmsg->ndtm_family && tbl->family != ndtmsg->ndtm_family)
2338 continue;
2339 if (nla_strcmp(tb[NDTA_NAME], tbl->id) == 0) {
2340 found = true;
2341 break;
2342 }
2343 }
2344
2345 if (!found)
2346 return -ENOENT;
2347
2348 /*
2349 * We acquire tbl->lock to be nice to the periodic timers and
2350 * make sure they always see a consistent set of values.
2351 */
2352 write_lock_bh(&tbl->lock);
2353
2354 if (tb[NDTA_PARMS]) {
2355 struct nlattr *tbp[NDTPA_MAX+1];
2356 struct neigh_parms *p;
2357 int i, ifindex = 0;
2358
2359 err = nla_parse_nested_deprecated(tbp, NDTPA_MAX,
2360 tb[NDTA_PARMS],
2361 nl_ntbl_parm_policy, extack);
2362 if (err < 0)
2363 goto errout_tbl_lock;
2364
2365 if (tbp[NDTPA_IFINDEX])
2366 ifindex = nla_get_u32(tbp[NDTPA_IFINDEX]);
2367
2368 p = lookup_neigh_parms(tbl, net, ifindex);
2369 if (p == NULL) {
2370 err = -ENOENT;
2371 goto errout_tbl_lock;
2372 }
2373
2374 for (i = 1; i <= NDTPA_MAX; i++) {
2375 if (tbp[i] == NULL)
2376 continue;
2377
2378 switch (i) {
2379 case NDTPA_QUEUE_LEN:
2380 NEIGH_VAR_SET(p, QUEUE_LEN_BYTES,
2381 nla_get_u32(tbp[i]) *
2382 SKB_TRUESIZE(ETH_FRAME_LEN));
2383 break;
2384 case NDTPA_QUEUE_LENBYTES:
2385 NEIGH_VAR_SET(p, QUEUE_LEN_BYTES,
2386 nla_get_u32(tbp[i]));
2387 break;
2388 case NDTPA_PROXY_QLEN:
2389 NEIGH_VAR_SET(p, PROXY_QLEN,
2390 nla_get_u32(tbp[i]));
2391 break;
2392 case NDTPA_APP_PROBES:
2393 NEIGH_VAR_SET(p, APP_PROBES,
2394 nla_get_u32(tbp[i]));
2395 break;
2396 case NDTPA_UCAST_PROBES:
2397 NEIGH_VAR_SET(p, UCAST_PROBES,
2398 nla_get_u32(tbp[i]));
2399 break;
2400 case NDTPA_MCAST_PROBES:
2401 NEIGH_VAR_SET(p, MCAST_PROBES,
2402 nla_get_u32(tbp[i]));
2403 break;
2404 case NDTPA_MCAST_REPROBES:
2405 NEIGH_VAR_SET(p, MCAST_REPROBES,
2406 nla_get_u32(tbp[i]));
2407 break;
2408 case NDTPA_BASE_REACHABLE_TIME:
2409 NEIGH_VAR_SET(p, BASE_REACHABLE_TIME,
2410 nla_get_msecs(tbp[i]));
2411 /* update reachable_time as well, otherwise, the change will
2412 * only be effective after the next time neigh_periodic_work
2413 * decides to recompute it (can be multiple minutes)
2414 */
2415 p->reachable_time =
2416 neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME));
2417 break;
2418 case NDTPA_GC_STALETIME:
2419 NEIGH_VAR_SET(p, GC_STALETIME,
2420 nla_get_msecs(tbp[i]));
2421 break;
2422 case NDTPA_DELAY_PROBE_TIME:
2423 NEIGH_VAR_SET(p, DELAY_PROBE_TIME,
2424 nla_get_msecs(tbp[i]));
2425 call_netevent_notifiers(NETEVENT_DELAY_PROBE_TIME_UPDATE, p);
2426 break;
2427 case NDTPA_INTERVAL_PROBE_TIME_MS:
2428 NEIGH_VAR_SET(p, INTERVAL_PROBE_TIME_MS,
2429 nla_get_msecs(tbp[i]));
2430 break;
2431 case NDTPA_RETRANS_TIME:
2432 NEIGH_VAR_SET(p, RETRANS_TIME,
2433 nla_get_msecs(tbp[i]));
2434 break;
2435 case NDTPA_ANYCAST_DELAY:
2436 NEIGH_VAR_SET(p, ANYCAST_DELAY,
2437 nla_get_msecs(tbp[i]));
2438 break;
2439 case NDTPA_PROXY_DELAY:
2440 NEIGH_VAR_SET(p, PROXY_DELAY,
2441 nla_get_msecs(tbp[i]));
2442 break;
2443 case NDTPA_LOCKTIME:
2444 NEIGH_VAR_SET(p, LOCKTIME,
2445 nla_get_msecs(tbp[i]));
2446 break;
2447 }
2448 }
2449 }
2450
2451 err = -ENOENT;
2452 if ((tb[NDTA_THRESH1] || tb[NDTA_THRESH2] ||
2453 tb[NDTA_THRESH3] || tb[NDTA_GC_INTERVAL]) &&
2454 !net_eq(net, &init_net))
2455 goto errout_tbl_lock;
2456
2457 if (tb[NDTA_THRESH1])
2458 WRITE_ONCE(tbl->gc_thresh1, nla_get_u32(tb[NDTA_THRESH1]));
2459
2460 if (tb[NDTA_THRESH2])
2461 WRITE_ONCE(tbl->gc_thresh2, nla_get_u32(tb[NDTA_THRESH2]));
2462
2463 if (tb[NDTA_THRESH3])
2464 WRITE_ONCE(tbl->gc_thresh3, nla_get_u32(tb[NDTA_THRESH3]));
2465
2466 if (tb[NDTA_GC_INTERVAL])
2467 WRITE_ONCE(tbl->gc_interval, nla_get_msecs(tb[NDTA_GC_INTERVAL]));
2468
2469 err = 0;
2470
2471errout_tbl_lock:
2472 write_unlock_bh(&tbl->lock);
2473errout:
2474 return err;
2475}
2476
2477static int neightbl_valid_dump_info(const struct nlmsghdr *nlh,
2478 struct netlink_ext_ack *extack)
2479{
2480 struct ndtmsg *ndtm;
2481
2482 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ndtm))) {
2483 NL_SET_ERR_MSG(extack, "Invalid header for neighbor table dump request");
2484 return -EINVAL;
2485 }
2486
2487 ndtm = nlmsg_data(nlh);
2488 if (ndtm->ndtm_pad1 || ndtm->ndtm_pad2) {
2489 NL_SET_ERR_MSG(extack, "Invalid values in header for neighbor table dump request");
2490 return -EINVAL;
2491 }
2492
2493 if (nlmsg_attrlen(nlh, sizeof(*ndtm))) {
2494 NL_SET_ERR_MSG(extack, "Invalid data after header in neighbor table dump request");
2495 return -EINVAL;
2496 }
2497
2498 return 0;
2499}
2500
2501static int neightbl_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
2502{
2503 const struct nlmsghdr *nlh = cb->nlh;
2504 struct net *net = sock_net(skb->sk);
2505 int family, tidx, nidx = 0;
2506 int tbl_skip = cb->args[0];
2507 int neigh_skip = cb->args[1];
2508 struct neigh_table *tbl;
2509
2510 if (cb->strict_check) {
2511 int err = neightbl_valid_dump_info(nlh, cb->extack);
2512
2513 if (err < 0)
2514 return err;
2515 }
2516
2517 family = ((struct rtgenmsg *)nlmsg_data(nlh))->rtgen_family;
2518
2519 for (tidx = 0; tidx < NEIGH_NR_TABLES; tidx++) {
2520 struct neigh_parms *p;
2521
2522 tbl = neigh_tables[tidx];
2523 if (!tbl)
2524 continue;
2525
2526 if (tidx < tbl_skip || (family && tbl->family != family))
2527 continue;
2528
2529 if (neightbl_fill_info(skb, tbl, NETLINK_CB(cb->skb).portid,
2530 nlh->nlmsg_seq, RTM_NEWNEIGHTBL,
2531 NLM_F_MULTI) < 0)
2532 break;
2533
2534 nidx = 0;
2535 p = list_next_entry(&tbl->parms, list);
2536 list_for_each_entry_from(p, &tbl->parms_list, list) {
2537 if (!net_eq(neigh_parms_net(p), net))
2538 continue;
2539
2540 if (nidx < neigh_skip)
2541 goto next;
2542
2543 if (neightbl_fill_param_info(skb, tbl, p,
2544 NETLINK_CB(cb->skb).portid,
2545 nlh->nlmsg_seq,
2546 RTM_NEWNEIGHTBL,
2547 NLM_F_MULTI) < 0)
2548 goto out;
2549 next:
2550 nidx++;
2551 }
2552
2553 neigh_skip = 0;
2554 }
2555out:
2556 cb->args[0] = tidx;
2557 cb->args[1] = nidx;
2558
2559 return skb->len;
2560}
2561
2562static int neigh_fill_info(struct sk_buff *skb, struct neighbour *neigh,
2563 u32 pid, u32 seq, int type, unsigned int flags)
2564{
2565 u32 neigh_flags, neigh_flags_ext;
2566 unsigned long now = jiffies;
2567 struct nda_cacheinfo ci;
2568 struct nlmsghdr *nlh;
2569 struct ndmsg *ndm;
2570
2571 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndm), flags);
2572 if (nlh == NULL)
2573 return -EMSGSIZE;
2574
2575 neigh_flags_ext = neigh->flags >> NTF_EXT_SHIFT;
2576 neigh_flags = neigh->flags & NTF_OLD_MASK;
2577
2578 ndm = nlmsg_data(nlh);
2579 ndm->ndm_family = neigh->ops->family;
2580 ndm->ndm_pad1 = 0;
2581 ndm->ndm_pad2 = 0;
2582 ndm->ndm_flags = neigh_flags;
2583 ndm->ndm_type = neigh->type;
2584 ndm->ndm_ifindex = neigh->dev->ifindex;
2585
2586 if (nla_put(skb, NDA_DST, neigh->tbl->key_len, neigh->primary_key))
2587 goto nla_put_failure;
2588
2589 read_lock_bh(&neigh->lock);
2590 ndm->ndm_state = neigh->nud_state;
2591 if (neigh->nud_state & NUD_VALID) {
2592 char haddr[MAX_ADDR_LEN];
2593
2594 neigh_ha_snapshot(haddr, neigh, neigh->dev);
2595 if (nla_put(skb, NDA_LLADDR, neigh->dev->addr_len, haddr) < 0) {
2596 read_unlock_bh(&neigh->lock);
2597 goto nla_put_failure;
2598 }
2599 }
2600
2601 ci.ndm_used = jiffies_to_clock_t(now - neigh->used);
2602 ci.ndm_confirmed = jiffies_to_clock_t(now - neigh->confirmed);
2603 ci.ndm_updated = jiffies_to_clock_t(now - neigh->updated);
2604 ci.ndm_refcnt = refcount_read(&neigh->refcnt) - 1;
2605 read_unlock_bh(&neigh->lock);
2606
2607 if (nla_put_u32(skb, NDA_PROBES, atomic_read(&neigh->probes)) ||
2608 nla_put(skb, NDA_CACHEINFO, sizeof(ci), &ci))
2609 goto nla_put_failure;
2610
2611 if (neigh->protocol && nla_put_u8(skb, NDA_PROTOCOL, neigh->protocol))
2612 goto nla_put_failure;
2613 if (neigh_flags_ext && nla_put_u32(skb, NDA_FLAGS_EXT, neigh_flags_ext))
2614 goto nla_put_failure;
2615
2616 nlmsg_end(skb, nlh);
2617 return 0;
2618
2619nla_put_failure:
2620 nlmsg_cancel(skb, nlh);
2621 return -EMSGSIZE;
2622}
2623
2624static int pneigh_fill_info(struct sk_buff *skb, struct pneigh_entry *pn,
2625 u32 pid, u32 seq, int type, unsigned int flags,
2626 struct neigh_table *tbl)
2627{
2628 u32 neigh_flags, neigh_flags_ext;
2629 struct nlmsghdr *nlh;
2630 struct ndmsg *ndm;
2631
2632 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndm), flags);
2633 if (nlh == NULL)
2634 return -EMSGSIZE;
2635
2636 neigh_flags_ext = pn->flags >> NTF_EXT_SHIFT;
2637 neigh_flags = pn->flags & NTF_OLD_MASK;
2638
2639 ndm = nlmsg_data(nlh);
2640 ndm->ndm_family = tbl->family;
2641 ndm->ndm_pad1 = 0;
2642 ndm->ndm_pad2 = 0;
2643 ndm->ndm_flags = neigh_flags | NTF_PROXY;
2644 ndm->ndm_type = RTN_UNICAST;
2645 ndm->ndm_ifindex = pn->dev ? pn->dev->ifindex : 0;
2646 ndm->ndm_state = NUD_NONE;
2647
2648 if (nla_put(skb, NDA_DST, tbl->key_len, pn->key))
2649 goto nla_put_failure;
2650
2651 if (pn->protocol && nla_put_u8(skb, NDA_PROTOCOL, pn->protocol))
2652 goto nla_put_failure;
2653 if (neigh_flags_ext && nla_put_u32(skb, NDA_FLAGS_EXT, neigh_flags_ext))
2654 goto nla_put_failure;
2655
2656 nlmsg_end(skb, nlh);
2657 return 0;
2658
2659nla_put_failure:
2660 nlmsg_cancel(skb, nlh);
2661 return -EMSGSIZE;
2662}
2663
2664static void neigh_update_notify(struct neighbour *neigh, u32 nlmsg_pid)
2665{
2666 call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, neigh);
2667 __neigh_notify(neigh, RTM_NEWNEIGH, 0, nlmsg_pid);
2668}
2669
2670static bool neigh_master_filtered(struct net_device *dev, int master_idx)
2671{
2672 struct net_device *master;
2673
2674 if (!master_idx)
2675 return false;
2676
2677 master = dev ? netdev_master_upper_dev_get(dev) : NULL;
2678
2679 /* 0 is already used to denote NDA_MASTER wasn't passed, therefore need another
2680 * invalid value for ifindex to denote "no master".
2681 */
2682 if (master_idx == -1)
2683 return !!master;
2684
2685 if (!master || master->ifindex != master_idx)
2686 return true;
2687
2688 return false;
2689}
2690
2691static bool neigh_ifindex_filtered(struct net_device *dev, int filter_idx)
2692{
2693 if (filter_idx && (!dev || dev->ifindex != filter_idx))
2694 return true;
2695
2696 return false;
2697}
2698
2699struct neigh_dump_filter {
2700 int master_idx;
2701 int dev_idx;
2702};
2703
2704static int neigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb,
2705 struct netlink_callback *cb,
2706 struct neigh_dump_filter *filter)
2707{
2708 struct net *net = sock_net(skb->sk);
2709 struct neighbour *n;
2710 int rc, h, s_h = cb->args[1];
2711 int idx, s_idx = idx = cb->args[2];
2712 struct neigh_hash_table *nht;
2713 unsigned int flags = NLM_F_MULTI;
2714
2715 if (filter->dev_idx || filter->master_idx)
2716 flags |= NLM_F_DUMP_FILTERED;
2717
2718 rcu_read_lock();
2719 nht = rcu_dereference(tbl->nht);
2720
2721 for (h = s_h; h < (1 << nht->hash_shift); h++) {
2722 if (h > s_h)
2723 s_idx = 0;
2724 for (n = rcu_dereference(nht->hash_buckets[h]), idx = 0;
2725 n != NULL;
2726 n = rcu_dereference(n->next)) {
2727 if (idx < s_idx || !net_eq(dev_net(n->dev), net))
2728 goto next;
2729 if (neigh_ifindex_filtered(n->dev, filter->dev_idx) ||
2730 neigh_master_filtered(n->dev, filter->master_idx))
2731 goto next;
2732 if (neigh_fill_info(skb, n, NETLINK_CB(cb->skb).portid,
2733 cb->nlh->nlmsg_seq,
2734 RTM_NEWNEIGH,
2735 flags) < 0) {
2736 rc = -1;
2737 goto out;
2738 }
2739next:
2740 idx++;
2741 }
2742 }
2743 rc = skb->len;
2744out:
2745 rcu_read_unlock();
2746 cb->args[1] = h;
2747 cb->args[2] = idx;
2748 return rc;
2749}
2750
2751static int pneigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb,
2752 struct netlink_callback *cb,
2753 struct neigh_dump_filter *filter)
2754{
2755 struct pneigh_entry *n;
2756 struct net *net = sock_net(skb->sk);
2757 int rc, h, s_h = cb->args[3];
2758 int idx, s_idx = idx = cb->args[4];
2759 unsigned int flags = NLM_F_MULTI;
2760
2761 if (filter->dev_idx || filter->master_idx)
2762 flags |= NLM_F_DUMP_FILTERED;
2763
2764 read_lock_bh(&tbl->lock);
2765
2766 for (h = s_h; h <= PNEIGH_HASHMASK; h++) {
2767 if (h > s_h)
2768 s_idx = 0;
2769 for (n = tbl->phash_buckets[h], idx = 0; n; n = n->next) {
2770 if (idx < s_idx || pneigh_net(n) != net)
2771 goto next;
2772 if (neigh_ifindex_filtered(n->dev, filter->dev_idx) ||
2773 neigh_master_filtered(n->dev, filter->master_idx))
2774 goto next;
2775 if (pneigh_fill_info(skb, n, NETLINK_CB(cb->skb).portid,
2776 cb->nlh->nlmsg_seq,
2777 RTM_NEWNEIGH, flags, tbl) < 0) {
2778 read_unlock_bh(&tbl->lock);
2779 rc = -1;
2780 goto out;
2781 }
2782 next:
2783 idx++;
2784 }
2785 }
2786
2787 read_unlock_bh(&tbl->lock);
2788 rc = skb->len;
2789out:
2790 cb->args[3] = h;
2791 cb->args[4] = idx;
2792 return rc;
2793
2794}
2795
2796static int neigh_valid_dump_req(const struct nlmsghdr *nlh,
2797 bool strict_check,
2798 struct neigh_dump_filter *filter,
2799 struct netlink_ext_ack *extack)
2800{
2801 struct nlattr *tb[NDA_MAX + 1];
2802 int err, i;
2803
2804 if (strict_check) {
2805 struct ndmsg *ndm;
2806
2807 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ndm))) {
2808 NL_SET_ERR_MSG(extack, "Invalid header for neighbor dump request");
2809 return -EINVAL;
2810 }
2811
2812 ndm = nlmsg_data(nlh);
2813 if (ndm->ndm_pad1 || ndm->ndm_pad2 || ndm->ndm_ifindex ||
2814 ndm->ndm_state || ndm->ndm_type) {
2815 NL_SET_ERR_MSG(extack, "Invalid values in header for neighbor dump request");
2816 return -EINVAL;
2817 }
2818
2819 if (ndm->ndm_flags & ~NTF_PROXY) {
2820 NL_SET_ERR_MSG(extack, "Invalid flags in header for neighbor dump request");
2821 return -EINVAL;
2822 }
2823
2824 err = nlmsg_parse_deprecated_strict(nlh, sizeof(struct ndmsg),
2825 tb, NDA_MAX, nda_policy,
2826 extack);
2827 } else {
2828 err = nlmsg_parse_deprecated(nlh, sizeof(struct ndmsg), tb,
2829 NDA_MAX, nda_policy, extack);
2830 }
2831 if (err < 0)
2832 return err;
2833
2834 for (i = 0; i <= NDA_MAX; ++i) {
2835 if (!tb[i])
2836 continue;
2837
2838 /* all new attributes should require strict_check */
2839 switch (i) {
2840 case NDA_IFINDEX:
2841 filter->dev_idx = nla_get_u32(tb[i]);
2842 break;
2843 case NDA_MASTER:
2844 filter->master_idx = nla_get_u32(tb[i]);
2845 break;
2846 default:
2847 if (strict_check) {
2848 NL_SET_ERR_MSG(extack, "Unsupported attribute in neighbor dump request");
2849 return -EINVAL;
2850 }
2851 }
2852 }
2853
2854 return 0;
2855}
2856
2857static int neigh_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
2858{
2859 const struct nlmsghdr *nlh = cb->nlh;
2860 struct neigh_dump_filter filter = {};
2861 struct neigh_table *tbl;
2862 int t, family, s_t;
2863 int proxy = 0;
2864 int err;
2865
2866 family = ((struct rtgenmsg *)nlmsg_data(nlh))->rtgen_family;
2867
2868 /* check for full ndmsg structure presence, family member is
2869 * the same for both structures
2870 */
2871 if (nlmsg_len(nlh) >= sizeof(struct ndmsg) &&
2872 ((struct ndmsg *)nlmsg_data(nlh))->ndm_flags == NTF_PROXY)
2873 proxy = 1;
2874
2875 err = neigh_valid_dump_req(nlh, cb->strict_check, &filter, cb->extack);
2876 if (err < 0 && cb->strict_check)
2877 return err;
2878
2879 s_t = cb->args[0];
2880
2881 for (t = 0; t < NEIGH_NR_TABLES; t++) {
2882 tbl = neigh_tables[t];
2883
2884 if (!tbl)
2885 continue;
2886 if (t < s_t || (family && tbl->family != family))
2887 continue;
2888 if (t > s_t)
2889 memset(&cb->args[1], 0, sizeof(cb->args) -
2890 sizeof(cb->args[0]));
2891 if (proxy)
2892 err = pneigh_dump_table(tbl, skb, cb, &filter);
2893 else
2894 err = neigh_dump_table(tbl, skb, cb, &filter);
2895 if (err < 0)
2896 break;
2897 }
2898
2899 cb->args[0] = t;
2900 return skb->len;
2901}
2902
2903static int neigh_valid_get_req(const struct nlmsghdr *nlh,
2904 struct neigh_table **tbl,
2905 void **dst, int *dev_idx, u8 *ndm_flags,
2906 struct netlink_ext_ack *extack)
2907{
2908 struct nlattr *tb[NDA_MAX + 1];
2909 struct ndmsg *ndm;
2910 int err, i;
2911
2912 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ndm))) {
2913 NL_SET_ERR_MSG(extack, "Invalid header for neighbor get request");
2914 return -EINVAL;
2915 }
2916
2917 ndm = nlmsg_data(nlh);
2918 if (ndm->ndm_pad1 || ndm->ndm_pad2 || ndm->ndm_state ||
2919 ndm->ndm_type) {
2920 NL_SET_ERR_MSG(extack, "Invalid values in header for neighbor get request");
2921 return -EINVAL;
2922 }
2923
2924 if (ndm->ndm_flags & ~NTF_PROXY) {
2925 NL_SET_ERR_MSG(extack, "Invalid flags in header for neighbor get request");
2926 return -EINVAL;
2927 }
2928
2929 err = nlmsg_parse_deprecated_strict(nlh, sizeof(struct ndmsg), tb,
2930 NDA_MAX, nda_policy, extack);
2931 if (err < 0)
2932 return err;
2933
2934 *ndm_flags = ndm->ndm_flags;
2935 *dev_idx = ndm->ndm_ifindex;
2936 *tbl = neigh_find_table(ndm->ndm_family);
2937 if (*tbl == NULL) {
2938 NL_SET_ERR_MSG(extack, "Unsupported family in header for neighbor get request");
2939 return -EAFNOSUPPORT;
2940 }
2941
2942 for (i = 0; i <= NDA_MAX; ++i) {
2943 if (!tb[i])
2944 continue;
2945
2946 switch (i) {
2947 case NDA_DST:
2948 if (nla_len(tb[i]) != (int)(*tbl)->key_len) {
2949 NL_SET_ERR_MSG(extack, "Invalid network address in neighbor get request");
2950 return -EINVAL;
2951 }
2952 *dst = nla_data(tb[i]);
2953 break;
2954 default:
2955 NL_SET_ERR_MSG(extack, "Unsupported attribute in neighbor get request");
2956 return -EINVAL;
2957 }
2958 }
2959
2960 return 0;
2961}
2962
2963static inline size_t neigh_nlmsg_size(void)
2964{
2965 return NLMSG_ALIGN(sizeof(struct ndmsg))
2966 + nla_total_size(MAX_ADDR_LEN) /* NDA_DST */
2967 + nla_total_size(MAX_ADDR_LEN) /* NDA_LLADDR */
2968 + nla_total_size(sizeof(struct nda_cacheinfo))
2969 + nla_total_size(4) /* NDA_PROBES */
2970 + nla_total_size(4) /* NDA_FLAGS_EXT */
2971 + nla_total_size(1); /* NDA_PROTOCOL */
2972}
2973
2974static int neigh_get_reply(struct net *net, struct neighbour *neigh,
2975 u32 pid, u32 seq)
2976{
2977 struct sk_buff *skb;
2978 int err = 0;
2979
2980 skb = nlmsg_new(neigh_nlmsg_size(), GFP_KERNEL);
2981 if (!skb)
2982 return -ENOBUFS;
2983
2984 err = neigh_fill_info(skb, neigh, pid, seq, RTM_NEWNEIGH, 0);
2985 if (err) {
2986 kfree_skb(skb);
2987 goto errout;
2988 }
2989
2990 err = rtnl_unicast(skb, net, pid);
2991errout:
2992 return err;
2993}
2994
2995static inline size_t pneigh_nlmsg_size(void)
2996{
2997 return NLMSG_ALIGN(sizeof(struct ndmsg))
2998 + nla_total_size(MAX_ADDR_LEN) /* NDA_DST */
2999 + nla_total_size(4) /* NDA_FLAGS_EXT */
3000 + nla_total_size(1); /* NDA_PROTOCOL */
3001}
3002
3003static int pneigh_get_reply(struct net *net, struct pneigh_entry *neigh,
3004 u32 pid, u32 seq, struct neigh_table *tbl)
3005{
3006 struct sk_buff *skb;
3007 int err = 0;
3008
3009 skb = nlmsg_new(pneigh_nlmsg_size(), GFP_KERNEL);
3010 if (!skb)
3011 return -ENOBUFS;
3012
3013 err = pneigh_fill_info(skb, neigh, pid, seq, RTM_NEWNEIGH, 0, tbl);
3014 if (err) {
3015 kfree_skb(skb);
3016 goto errout;
3017 }
3018
3019 err = rtnl_unicast(skb, net, pid);
3020errout:
3021 return err;
3022}
3023
3024static int neigh_get(struct sk_buff *in_skb, struct nlmsghdr *nlh,
3025 struct netlink_ext_ack *extack)
3026{
3027 struct net *net = sock_net(in_skb->sk);
3028 struct net_device *dev = NULL;
3029 struct neigh_table *tbl = NULL;
3030 struct neighbour *neigh;
3031 void *dst = NULL;
3032 u8 ndm_flags = 0;
3033 int dev_idx = 0;
3034 int err;
3035
3036 err = neigh_valid_get_req(nlh, &tbl, &dst, &dev_idx, &ndm_flags,
3037 extack);
3038 if (err < 0)
3039 return err;
3040
3041 if (dev_idx) {
3042 dev = __dev_get_by_index(net, dev_idx);
3043 if (!dev) {
3044 NL_SET_ERR_MSG(extack, "Unknown device ifindex");
3045 return -ENODEV;
3046 }
3047 }
3048
3049 if (!dst) {
3050 NL_SET_ERR_MSG(extack, "Network address not specified");
3051 return -EINVAL;
3052 }
3053
3054 if (ndm_flags & NTF_PROXY) {
3055 struct pneigh_entry *pn;
3056
3057 pn = pneigh_lookup(tbl, net, dst, dev, 0);
3058 if (!pn) {
3059 NL_SET_ERR_MSG(extack, "Proxy neighbour entry not found");
3060 return -ENOENT;
3061 }
3062 return pneigh_get_reply(net, pn, NETLINK_CB(in_skb).portid,
3063 nlh->nlmsg_seq, tbl);
3064 }
3065
3066 if (!dev) {
3067 NL_SET_ERR_MSG(extack, "No device specified");
3068 return -EINVAL;
3069 }
3070
3071 neigh = neigh_lookup(tbl, dst, dev);
3072 if (!neigh) {
3073 NL_SET_ERR_MSG(extack, "Neighbour entry not found");
3074 return -ENOENT;
3075 }
3076
3077 err = neigh_get_reply(net, neigh, NETLINK_CB(in_skb).portid,
3078 nlh->nlmsg_seq);
3079
3080 neigh_release(neigh);
3081
3082 return err;
3083}
3084
3085void neigh_for_each(struct neigh_table *tbl, void (*cb)(struct neighbour *, void *), void *cookie)
3086{
3087 int chain;
3088 struct neigh_hash_table *nht;
3089
3090 rcu_read_lock();
3091 nht = rcu_dereference(tbl->nht);
3092
3093 read_lock_bh(&tbl->lock); /* avoid resizes */
3094 for (chain = 0; chain < (1 << nht->hash_shift); chain++) {
3095 struct neighbour *n;
3096
3097 for (n = rcu_dereference(nht->hash_buckets[chain]);
3098 n != NULL;
3099 n = rcu_dereference(n->next))
3100 cb(n, cookie);
3101 }
3102 read_unlock_bh(&tbl->lock);
3103 rcu_read_unlock();
3104}
3105EXPORT_SYMBOL(neigh_for_each);
3106
3107/* The tbl->lock must be held as a writer and BH disabled. */
3108void __neigh_for_each_release(struct neigh_table *tbl,
3109 int (*cb)(struct neighbour *))
3110{
3111 int chain;
3112 struct neigh_hash_table *nht;
3113
3114 nht = rcu_dereference_protected(tbl->nht,
3115 lockdep_is_held(&tbl->lock));
3116 for (chain = 0; chain < (1 << nht->hash_shift); chain++) {
3117 struct neighbour *n;
3118 struct neighbour __rcu **np;
3119
3120 np = &nht->hash_buckets[chain];
3121 while ((n = rcu_dereference_protected(*np,
3122 lockdep_is_held(&tbl->lock))) != NULL) {
3123 int release;
3124
3125 write_lock(&n->lock);
3126 release = cb(n);
3127 if (release) {
3128 rcu_assign_pointer(*np,
3129 rcu_dereference_protected(n->next,
3130 lockdep_is_held(&tbl->lock)));
3131 neigh_mark_dead(n);
3132 } else
3133 np = &n->next;
3134 write_unlock(&n->lock);
3135 if (release)
3136 neigh_cleanup_and_release(n);
3137 }
3138 }
3139}
3140EXPORT_SYMBOL(__neigh_for_each_release);
3141
3142int neigh_xmit(int index, struct net_device *dev,
3143 const void *addr, struct sk_buff *skb)
3144{
3145 int err = -EAFNOSUPPORT;
3146 if (likely(index < NEIGH_NR_TABLES)) {
3147 struct neigh_table *tbl;
3148 struct neighbour *neigh;
3149
3150 tbl = neigh_tables[index];
3151 if (!tbl)
3152 goto out;
3153 rcu_read_lock();
3154 if (index == NEIGH_ARP_TABLE) {
3155 u32 key = *((u32 *)addr);
3156
3157 neigh = __ipv4_neigh_lookup_noref(dev, key);
3158 } else {
3159 neigh = __neigh_lookup_noref(tbl, addr, dev);
3160 }
3161 if (!neigh)
3162 neigh = __neigh_create(tbl, addr, dev, false);
3163 err = PTR_ERR(neigh);
3164 if (IS_ERR(neigh)) {
3165 rcu_read_unlock();
3166 goto out_kfree_skb;
3167 }
3168 err = READ_ONCE(neigh->output)(neigh, skb);
3169 rcu_read_unlock();
3170 }
3171 else if (index == NEIGH_LINK_TABLE) {
3172 err = dev_hard_header(skb, dev, ntohs(skb->protocol),
3173 addr, NULL, skb->len);
3174 if (err < 0)
3175 goto out_kfree_skb;
3176 err = dev_queue_xmit(skb);
3177 }
3178out:
3179 return err;
3180out_kfree_skb:
3181 kfree_skb(skb);
3182 goto out;
3183}
3184EXPORT_SYMBOL(neigh_xmit);
3185
3186#ifdef CONFIG_PROC_FS
3187
3188static struct neighbour *neigh_get_first(struct seq_file *seq)
3189{
3190 struct neigh_seq_state *state = seq->private;
3191 struct net *net = seq_file_net(seq);
3192 struct neigh_hash_table *nht = state->nht;
3193 struct neighbour *n = NULL;
3194 int bucket;
3195
3196 state->flags &= ~NEIGH_SEQ_IS_PNEIGH;
3197 for (bucket = 0; bucket < (1 << nht->hash_shift); bucket++) {
3198 n = rcu_dereference(nht->hash_buckets[bucket]);
3199
3200 while (n) {
3201 if (!net_eq(dev_net(n->dev), net))
3202 goto next;
3203 if (state->neigh_sub_iter) {
3204 loff_t fakep = 0;
3205 void *v;
3206
3207 v = state->neigh_sub_iter(state, n, &fakep);
3208 if (!v)
3209 goto next;
3210 }
3211 if (!(state->flags & NEIGH_SEQ_SKIP_NOARP))
3212 break;
3213 if (READ_ONCE(n->nud_state) & ~NUD_NOARP)
3214 break;
3215next:
3216 n = rcu_dereference(n->next);
3217 }
3218
3219 if (n)
3220 break;
3221 }
3222 state->bucket = bucket;
3223
3224 return n;
3225}
3226
3227static struct neighbour *neigh_get_next(struct seq_file *seq,
3228 struct neighbour *n,
3229 loff_t *pos)
3230{
3231 struct neigh_seq_state *state = seq->private;
3232 struct net *net = seq_file_net(seq);
3233 struct neigh_hash_table *nht = state->nht;
3234
3235 if (state->neigh_sub_iter) {
3236 void *v = state->neigh_sub_iter(state, n, pos);
3237 if (v)
3238 return n;
3239 }
3240 n = rcu_dereference(n->next);
3241
3242 while (1) {
3243 while (n) {
3244 if (!net_eq(dev_net(n->dev), net))
3245 goto next;
3246 if (state->neigh_sub_iter) {
3247 void *v = state->neigh_sub_iter(state, n, pos);
3248 if (v)
3249 return n;
3250 goto next;
3251 }
3252 if (!(state->flags & NEIGH_SEQ_SKIP_NOARP))
3253 break;
3254
3255 if (READ_ONCE(n->nud_state) & ~NUD_NOARP)
3256 break;
3257next:
3258 n = rcu_dereference(n->next);
3259 }
3260
3261 if (n)
3262 break;
3263
3264 if (++state->bucket >= (1 << nht->hash_shift))
3265 break;
3266
3267 n = rcu_dereference(nht->hash_buckets[state->bucket]);
3268 }
3269
3270 if (n && pos)
3271 --(*pos);
3272 return n;
3273}
3274
3275static struct neighbour *neigh_get_idx(struct seq_file *seq, loff_t *pos)
3276{
3277 struct neighbour *n = neigh_get_first(seq);
3278
3279 if (n) {
3280 --(*pos);
3281 while (*pos) {
3282 n = neigh_get_next(seq, n, pos);
3283 if (!n)
3284 break;
3285 }
3286 }
3287 return *pos ? NULL : n;
3288}
3289
3290static struct pneigh_entry *pneigh_get_first(struct seq_file *seq)
3291{
3292 struct neigh_seq_state *state = seq->private;
3293 struct net *net = seq_file_net(seq);
3294 struct neigh_table *tbl = state->tbl;
3295 struct pneigh_entry *pn = NULL;
3296 int bucket;
3297
3298 state->flags |= NEIGH_SEQ_IS_PNEIGH;
3299 for (bucket = 0; bucket <= PNEIGH_HASHMASK; bucket++) {
3300 pn = tbl->phash_buckets[bucket];
3301 while (pn && !net_eq(pneigh_net(pn), net))
3302 pn = pn->next;
3303 if (pn)
3304 break;
3305 }
3306 state->bucket = bucket;
3307
3308 return pn;
3309}
3310
3311static struct pneigh_entry *pneigh_get_next(struct seq_file *seq,
3312 struct pneigh_entry *pn,
3313 loff_t *pos)
3314{
3315 struct neigh_seq_state *state = seq->private;
3316 struct net *net = seq_file_net(seq);
3317 struct neigh_table *tbl = state->tbl;
3318
3319 do {
3320 pn = pn->next;
3321 } while (pn && !net_eq(pneigh_net(pn), net));
3322
3323 while (!pn) {
3324 if (++state->bucket > PNEIGH_HASHMASK)
3325 break;
3326 pn = tbl->phash_buckets[state->bucket];
3327 while (pn && !net_eq(pneigh_net(pn), net))
3328 pn = pn->next;
3329 if (pn)
3330 break;
3331 }
3332
3333 if (pn && pos)
3334 --(*pos);
3335
3336 return pn;
3337}
3338
3339static struct pneigh_entry *pneigh_get_idx(struct seq_file *seq, loff_t *pos)
3340{
3341 struct pneigh_entry *pn = pneigh_get_first(seq);
3342
3343 if (pn) {
3344 --(*pos);
3345 while (*pos) {
3346 pn = pneigh_get_next(seq, pn, pos);
3347 if (!pn)
3348 break;
3349 }
3350 }
3351 return *pos ? NULL : pn;
3352}
3353
3354static void *neigh_get_idx_any(struct seq_file *seq, loff_t *pos)
3355{
3356 struct neigh_seq_state *state = seq->private;
3357 void *rc;
3358 loff_t idxpos = *pos;
3359
3360 rc = neigh_get_idx(seq, &idxpos);
3361 if (!rc && !(state->flags & NEIGH_SEQ_NEIGH_ONLY))
3362 rc = pneigh_get_idx(seq, &idxpos);
3363
3364 return rc;
3365}
3366
3367void *neigh_seq_start(struct seq_file *seq, loff_t *pos, struct neigh_table *tbl, unsigned int neigh_seq_flags)
3368 __acquires(tbl->lock)
3369 __acquires(rcu)
3370{
3371 struct neigh_seq_state *state = seq->private;
3372
3373 state->tbl = tbl;
3374 state->bucket = 0;
3375 state->flags = (neigh_seq_flags & ~NEIGH_SEQ_IS_PNEIGH);
3376
3377 rcu_read_lock();
3378 state->nht = rcu_dereference(tbl->nht);
3379 read_lock_bh(&tbl->lock);
3380
3381 return *pos ? neigh_get_idx_any(seq, pos) : SEQ_START_TOKEN;
3382}
3383EXPORT_SYMBOL(neigh_seq_start);
3384
3385void *neigh_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3386{
3387 struct neigh_seq_state *state;
3388 void *rc;
3389
3390 if (v == SEQ_START_TOKEN) {
3391 rc = neigh_get_first(seq);
3392 goto out;
3393 }
3394
3395 state = seq->private;
3396 if (!(state->flags & NEIGH_SEQ_IS_PNEIGH)) {
3397 rc = neigh_get_next(seq, v, NULL);
3398 if (rc)
3399 goto out;
3400 if (!(state->flags & NEIGH_SEQ_NEIGH_ONLY))
3401 rc = pneigh_get_first(seq);
3402 } else {
3403 BUG_ON(state->flags & NEIGH_SEQ_NEIGH_ONLY);
3404 rc = pneigh_get_next(seq, v, NULL);
3405 }
3406out:
3407 ++(*pos);
3408 return rc;
3409}
3410EXPORT_SYMBOL(neigh_seq_next);
3411
3412void neigh_seq_stop(struct seq_file *seq, void *v)
3413 __releases(tbl->lock)
3414 __releases(rcu)
3415{
3416 struct neigh_seq_state *state = seq->private;
3417 struct neigh_table *tbl = state->tbl;
3418
3419 read_unlock_bh(&tbl->lock);
3420 rcu_read_unlock();
3421}
3422EXPORT_SYMBOL(neigh_seq_stop);
3423
3424/* statistics via seq_file */
3425
3426static void *neigh_stat_seq_start(struct seq_file *seq, loff_t *pos)
3427{
3428 struct neigh_table *tbl = pde_data(file_inode(seq->file));
3429 int cpu;
3430
3431 if (*pos == 0)
3432 return SEQ_START_TOKEN;
3433
3434 for (cpu = *pos-1; cpu < nr_cpu_ids; ++cpu) {
3435 if (!cpu_possible(cpu))
3436 continue;
3437 *pos = cpu+1;
3438 return per_cpu_ptr(tbl->stats, cpu);
3439 }
3440 return NULL;
3441}
3442
3443static void *neigh_stat_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3444{
3445 struct neigh_table *tbl = pde_data(file_inode(seq->file));
3446 int cpu;
3447
3448 for (cpu = *pos; cpu < nr_cpu_ids; ++cpu) {
3449 if (!cpu_possible(cpu))
3450 continue;
3451 *pos = cpu+1;
3452 return per_cpu_ptr(tbl->stats, cpu);
3453 }
3454 (*pos)++;
3455 return NULL;
3456}
3457
3458static void neigh_stat_seq_stop(struct seq_file *seq, void *v)
3459{
3460
3461}
3462
3463static int neigh_stat_seq_show(struct seq_file *seq, void *v)
3464{
3465 struct neigh_table *tbl = pde_data(file_inode(seq->file));
3466 struct neigh_statistics *st = v;
3467
3468 if (v == SEQ_START_TOKEN) {
3469 seq_puts(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");
3470 return 0;
3471 }
3472
3473 seq_printf(seq, "%08x %08lx %08lx %08lx %08lx %08lx %08lx "
3474 "%08lx %08lx %08lx "
3475 "%08lx %08lx %08lx\n",
3476 atomic_read(&tbl->entries),
3477
3478 st->allocs,
3479 st->destroys,
3480 st->hash_grows,
3481
3482 st->lookups,
3483 st->hits,
3484
3485 st->res_failed,
3486
3487 st->rcv_probes_mcast,
3488 st->rcv_probes_ucast,
3489
3490 st->periodic_gc_runs,
3491 st->forced_gc_runs,
3492 st->unres_discards,
3493 st->table_fulls
3494 );
3495
3496 return 0;
3497}
3498
3499static const struct seq_operations neigh_stat_seq_ops = {
3500 .start = neigh_stat_seq_start,
3501 .next = neigh_stat_seq_next,
3502 .stop = neigh_stat_seq_stop,
3503 .show = neigh_stat_seq_show,
3504};
3505#endif /* CONFIG_PROC_FS */
3506
3507static void __neigh_notify(struct neighbour *n, int type, int flags,
3508 u32 pid)
3509{
3510 struct net *net = dev_net(n->dev);
3511 struct sk_buff *skb;
3512 int err = -ENOBUFS;
3513
3514 skb = nlmsg_new(neigh_nlmsg_size(), GFP_ATOMIC);
3515 if (skb == NULL)
3516 goto errout;
3517
3518 err = neigh_fill_info(skb, n, pid, 0, type, flags);
3519 if (err < 0) {
3520 /* -EMSGSIZE implies BUG in neigh_nlmsg_size() */
3521 WARN_ON(err == -EMSGSIZE);
3522 kfree_skb(skb);
3523 goto errout;
3524 }
3525 rtnl_notify(skb, net, 0, RTNLGRP_NEIGH, NULL, GFP_ATOMIC);
3526 return;
3527errout:
3528 if (err < 0)
3529 rtnl_set_sk_err(net, RTNLGRP_NEIGH, err);
3530}
3531
3532void neigh_app_ns(struct neighbour *n)
3533{
3534 __neigh_notify(n, RTM_GETNEIGH, NLM_F_REQUEST, 0);
3535}
3536EXPORT_SYMBOL(neigh_app_ns);
3537
3538#ifdef CONFIG_SYSCTL
3539static int unres_qlen_max = INT_MAX / SKB_TRUESIZE(ETH_FRAME_LEN);
3540
3541static int proc_unres_qlen(struct ctl_table *ctl, int write,
3542 void *buffer, size_t *lenp, loff_t *ppos)
3543{
3544 int size, ret;
3545 struct ctl_table tmp = *ctl;
3546
3547 tmp.extra1 = SYSCTL_ZERO;
3548 tmp.extra2 = &unres_qlen_max;
3549 tmp.data = &size;
3550
3551 size = *(int *)ctl->data / SKB_TRUESIZE(ETH_FRAME_LEN);
3552 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
3553
3554 if (write && !ret)
3555 *(int *)ctl->data = size * SKB_TRUESIZE(ETH_FRAME_LEN);
3556 return ret;
3557}
3558
3559static void neigh_copy_dflt_parms(struct net *net, struct neigh_parms *p,
3560 int index)
3561{
3562 struct net_device *dev;
3563 int family = neigh_parms_family(p);
3564
3565 rcu_read_lock();
3566 for_each_netdev_rcu(net, dev) {
3567 struct neigh_parms *dst_p =
3568 neigh_get_dev_parms_rcu(dev, family);
3569
3570 if (dst_p && !test_bit(index, dst_p->data_state))
3571 dst_p->data[index] = p->data[index];
3572 }
3573 rcu_read_unlock();
3574}
3575
3576static void neigh_proc_update(struct ctl_table *ctl, int write)
3577{
3578 struct net_device *dev = ctl->extra1;
3579 struct neigh_parms *p = ctl->extra2;
3580 struct net *net = neigh_parms_net(p);
3581 int index = (int *) ctl->data - p->data;
3582
3583 if (!write)
3584 return;
3585
3586 set_bit(index, p->data_state);
3587 if (index == NEIGH_VAR_DELAY_PROBE_TIME)
3588 call_netevent_notifiers(NETEVENT_DELAY_PROBE_TIME_UPDATE, p);
3589 if (!dev) /* NULL dev means this is default value */
3590 neigh_copy_dflt_parms(net, p, index);
3591}
3592
3593static int neigh_proc_dointvec_zero_intmax(struct ctl_table *ctl, int write,
3594 void *buffer, size_t *lenp,
3595 loff_t *ppos)
3596{
3597 struct ctl_table tmp = *ctl;
3598 int ret;
3599
3600 tmp.extra1 = SYSCTL_ZERO;
3601 tmp.extra2 = SYSCTL_INT_MAX;
3602
3603 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
3604 neigh_proc_update(ctl, write);
3605 return ret;
3606}
3607
3608static int neigh_proc_dointvec_ms_jiffies_positive(struct ctl_table *ctl, int write,
3609 void *buffer, size_t *lenp, loff_t *ppos)
3610{
3611 struct ctl_table tmp = *ctl;
3612 int ret;
3613
3614 int min = msecs_to_jiffies(1);
3615
3616 tmp.extra1 = &min;
3617 tmp.extra2 = NULL;
3618
3619 ret = proc_dointvec_ms_jiffies_minmax(&tmp, write, buffer, lenp, ppos);
3620 neigh_proc_update(ctl, write);
3621 return ret;
3622}
3623
3624int neigh_proc_dointvec(struct ctl_table *ctl, int write, void *buffer,
3625 size_t *lenp, loff_t *ppos)
3626{
3627 int ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
3628
3629 neigh_proc_update(ctl, write);
3630 return ret;
3631}
3632EXPORT_SYMBOL(neigh_proc_dointvec);
3633
3634int neigh_proc_dointvec_jiffies(struct ctl_table *ctl, int write, void *buffer,
3635 size_t *lenp, loff_t *ppos)
3636{
3637 int ret = proc_dointvec_jiffies(ctl, write, buffer, lenp, ppos);
3638
3639 neigh_proc_update(ctl, write);
3640 return ret;
3641}
3642EXPORT_SYMBOL(neigh_proc_dointvec_jiffies);
3643
3644static int neigh_proc_dointvec_userhz_jiffies(struct ctl_table *ctl, int write,
3645 void *buffer, size_t *lenp,
3646 loff_t *ppos)
3647{
3648 int ret = proc_dointvec_userhz_jiffies(ctl, write, buffer, lenp, ppos);
3649
3650 neigh_proc_update(ctl, write);
3651 return ret;
3652}
3653
3654int neigh_proc_dointvec_ms_jiffies(struct ctl_table *ctl, int write,
3655 void *buffer, size_t *lenp, loff_t *ppos)
3656{
3657 int ret = proc_dointvec_ms_jiffies(ctl, write, buffer, lenp, ppos);
3658
3659 neigh_proc_update(ctl, write);
3660 return ret;
3661}
3662EXPORT_SYMBOL(neigh_proc_dointvec_ms_jiffies);
3663
3664static int neigh_proc_dointvec_unres_qlen(struct ctl_table *ctl, int write,
3665 void *buffer, size_t *lenp,
3666 loff_t *ppos)
3667{
3668 int ret = proc_unres_qlen(ctl, write, buffer, lenp, ppos);
3669
3670 neigh_proc_update(ctl, write);
3671 return ret;
3672}
3673
3674static int neigh_proc_base_reachable_time(struct ctl_table *ctl, int write,
3675 void *buffer, size_t *lenp,
3676 loff_t *ppos)
3677{
3678 struct neigh_parms *p = ctl->extra2;
3679 int ret;
3680
3681 if (strcmp(ctl->procname, "base_reachable_time") == 0)
3682 ret = neigh_proc_dointvec_jiffies(ctl, write, buffer, lenp, ppos);
3683 else if (strcmp(ctl->procname, "base_reachable_time_ms") == 0)
3684 ret = neigh_proc_dointvec_ms_jiffies(ctl, write, buffer, lenp, ppos);
3685 else
3686 ret = -1;
3687
3688 if (write && ret == 0) {
3689 /* update reachable_time as well, otherwise, the change will
3690 * only be effective after the next time neigh_periodic_work
3691 * decides to recompute it
3692 */
3693 p->reachable_time =
3694 neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME));
3695 }
3696 return ret;
3697}
3698
3699#define NEIGH_PARMS_DATA_OFFSET(index) \
3700 (&((struct neigh_parms *) 0)->data[index])
3701
3702#define NEIGH_SYSCTL_ENTRY(attr, data_attr, name, mval, proc) \
3703 [NEIGH_VAR_ ## attr] = { \
3704 .procname = name, \
3705 .data = NEIGH_PARMS_DATA_OFFSET(NEIGH_VAR_ ## data_attr), \
3706 .maxlen = sizeof(int), \
3707 .mode = mval, \
3708 .proc_handler = proc, \
3709 }
3710
3711#define NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(attr, name) \
3712 NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_zero_intmax)
3713
3714#define NEIGH_SYSCTL_JIFFIES_ENTRY(attr, name) \
3715 NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_jiffies)
3716
3717#define NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(attr, name) \
3718 NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_userhz_jiffies)
3719
3720#define NEIGH_SYSCTL_MS_JIFFIES_POSITIVE_ENTRY(attr, name) \
3721 NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_ms_jiffies_positive)
3722
3723#define NEIGH_SYSCTL_MS_JIFFIES_REUSED_ENTRY(attr, data_attr, name) \
3724 NEIGH_SYSCTL_ENTRY(attr, data_attr, name, 0644, neigh_proc_dointvec_ms_jiffies)
3725
3726#define NEIGH_SYSCTL_UNRES_QLEN_REUSED_ENTRY(attr, data_attr, name) \
3727 NEIGH_SYSCTL_ENTRY(attr, data_attr, name, 0644, neigh_proc_dointvec_unres_qlen)
3728
3729static struct neigh_sysctl_table {
3730 struct ctl_table_header *sysctl_header;
3731 struct ctl_table neigh_vars[NEIGH_VAR_MAX + 1];
3732} neigh_sysctl_template __read_mostly = {
3733 .neigh_vars = {
3734 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(MCAST_PROBES, "mcast_solicit"),
3735 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(UCAST_PROBES, "ucast_solicit"),
3736 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(APP_PROBES, "app_solicit"),
3737 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(MCAST_REPROBES, "mcast_resolicit"),
3738 NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(RETRANS_TIME, "retrans_time"),
3739 NEIGH_SYSCTL_JIFFIES_ENTRY(BASE_REACHABLE_TIME, "base_reachable_time"),
3740 NEIGH_SYSCTL_JIFFIES_ENTRY(DELAY_PROBE_TIME, "delay_first_probe_time"),
3741 NEIGH_SYSCTL_MS_JIFFIES_POSITIVE_ENTRY(INTERVAL_PROBE_TIME_MS,
3742 "interval_probe_time_ms"),
3743 NEIGH_SYSCTL_JIFFIES_ENTRY(GC_STALETIME, "gc_stale_time"),
3744 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(QUEUE_LEN_BYTES, "unres_qlen_bytes"),
3745 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(PROXY_QLEN, "proxy_qlen"),
3746 NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(ANYCAST_DELAY, "anycast_delay"),
3747 NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(PROXY_DELAY, "proxy_delay"),
3748 NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(LOCKTIME, "locktime"),
3749 NEIGH_SYSCTL_UNRES_QLEN_REUSED_ENTRY(QUEUE_LEN, QUEUE_LEN_BYTES, "unres_qlen"),
3750 NEIGH_SYSCTL_MS_JIFFIES_REUSED_ENTRY(RETRANS_TIME_MS, RETRANS_TIME, "retrans_time_ms"),
3751 NEIGH_SYSCTL_MS_JIFFIES_REUSED_ENTRY(BASE_REACHABLE_TIME_MS, BASE_REACHABLE_TIME, "base_reachable_time_ms"),
3752 [NEIGH_VAR_GC_INTERVAL] = {
3753 .procname = "gc_interval",
3754 .maxlen = sizeof(int),
3755 .mode = 0644,
3756 .proc_handler = proc_dointvec_jiffies,
3757 },
3758 [NEIGH_VAR_GC_THRESH1] = {
3759 .procname = "gc_thresh1",
3760 .maxlen = sizeof(int),
3761 .mode = 0644,
3762 .extra1 = SYSCTL_ZERO,
3763 .extra2 = SYSCTL_INT_MAX,
3764 .proc_handler = proc_dointvec_minmax,
3765 },
3766 [NEIGH_VAR_GC_THRESH2] = {
3767 .procname = "gc_thresh2",
3768 .maxlen = sizeof(int),
3769 .mode = 0644,
3770 .extra1 = SYSCTL_ZERO,
3771 .extra2 = SYSCTL_INT_MAX,
3772 .proc_handler = proc_dointvec_minmax,
3773 },
3774 [NEIGH_VAR_GC_THRESH3] = {
3775 .procname = "gc_thresh3",
3776 .maxlen = sizeof(int),
3777 .mode = 0644,
3778 .extra1 = SYSCTL_ZERO,
3779 .extra2 = SYSCTL_INT_MAX,
3780 .proc_handler = proc_dointvec_minmax,
3781 },
3782 {},
3783 },
3784};
3785
3786int neigh_sysctl_register(struct net_device *dev, struct neigh_parms *p,
3787 proc_handler *handler)
3788{
3789 int i;
3790 struct neigh_sysctl_table *t;
3791 const char *dev_name_source;
3792 char neigh_path[ sizeof("net//neigh/") + IFNAMSIZ + IFNAMSIZ ];
3793 char *p_name;
3794 size_t neigh_vars_size;
3795
3796 t = kmemdup(&neigh_sysctl_template, sizeof(*t), GFP_KERNEL_ACCOUNT);
3797 if (!t)
3798 goto err;
3799
3800 for (i = 0; i < NEIGH_VAR_GC_INTERVAL; i++) {
3801 t->neigh_vars[i].data += (long) p;
3802 t->neigh_vars[i].extra1 = dev;
3803 t->neigh_vars[i].extra2 = p;
3804 }
3805
3806 neigh_vars_size = ARRAY_SIZE(t->neigh_vars);
3807 if (dev) {
3808 dev_name_source = dev->name;
3809 /* Terminate the table early */
3810 memset(&t->neigh_vars[NEIGH_VAR_GC_INTERVAL], 0,
3811 sizeof(t->neigh_vars[NEIGH_VAR_GC_INTERVAL]));
3812 neigh_vars_size = NEIGH_VAR_BASE_REACHABLE_TIME_MS + 1;
3813 } else {
3814 struct neigh_table *tbl = p->tbl;
3815 dev_name_source = "default";
3816 t->neigh_vars[NEIGH_VAR_GC_INTERVAL].data = &tbl->gc_interval;
3817 t->neigh_vars[NEIGH_VAR_GC_THRESH1].data = &tbl->gc_thresh1;
3818 t->neigh_vars[NEIGH_VAR_GC_THRESH2].data = &tbl->gc_thresh2;
3819 t->neigh_vars[NEIGH_VAR_GC_THRESH3].data = &tbl->gc_thresh3;
3820 }
3821
3822 if (handler) {
3823 /* RetransTime */
3824 t->neigh_vars[NEIGH_VAR_RETRANS_TIME].proc_handler = handler;
3825 /* ReachableTime */
3826 t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME].proc_handler = handler;
3827 /* RetransTime (in milliseconds)*/
3828 t->neigh_vars[NEIGH_VAR_RETRANS_TIME_MS].proc_handler = handler;
3829 /* ReachableTime (in milliseconds) */
3830 t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME_MS].proc_handler = handler;
3831 } else {
3832 /* Those handlers will update p->reachable_time after
3833 * base_reachable_time(_ms) is set to ensure the new timer starts being
3834 * applied after the next neighbour update instead of waiting for
3835 * neigh_periodic_work to update its value (can be multiple minutes)
3836 * So any handler that replaces them should do this as well
3837 */
3838 /* ReachableTime */
3839 t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME].proc_handler =
3840 neigh_proc_base_reachable_time;
3841 /* ReachableTime (in milliseconds) */
3842 t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME_MS].proc_handler =
3843 neigh_proc_base_reachable_time;
3844 }
3845
3846 switch (neigh_parms_family(p)) {
3847 case AF_INET:
3848 p_name = "ipv4";
3849 break;
3850 case AF_INET6:
3851 p_name = "ipv6";
3852 break;
3853 default:
3854 BUG();
3855 }
3856
3857 snprintf(neigh_path, sizeof(neigh_path), "net/%s/neigh/%s",
3858 p_name, dev_name_source);
3859 t->sysctl_header = register_net_sysctl_sz(neigh_parms_net(p),
3860 neigh_path, t->neigh_vars,
3861 neigh_vars_size);
3862 if (!t->sysctl_header)
3863 goto free;
3864
3865 p->sysctl_table = t;
3866 return 0;
3867
3868free:
3869 kfree(t);
3870err:
3871 return -ENOBUFS;
3872}
3873EXPORT_SYMBOL(neigh_sysctl_register);
3874
3875void neigh_sysctl_unregister(struct neigh_parms *p)
3876{
3877 if (p->sysctl_table) {
3878 struct neigh_sysctl_table *t = p->sysctl_table;
3879 p->sysctl_table = NULL;
3880 unregister_net_sysctl_table(t->sysctl_header);
3881 kfree(t);
3882 }
3883}
3884EXPORT_SYMBOL(neigh_sysctl_unregister);
3885
3886#endif /* CONFIG_SYSCTL */
3887
3888static int __init neigh_init(void)
3889{
3890 rtnl_register(PF_UNSPEC, RTM_NEWNEIGH, neigh_add, NULL, 0);
3891 rtnl_register(PF_UNSPEC, RTM_DELNEIGH, neigh_delete, NULL, 0);
3892 rtnl_register(PF_UNSPEC, RTM_GETNEIGH, neigh_get, neigh_dump_info, 0);
3893
3894 rtnl_register(PF_UNSPEC, RTM_GETNEIGHTBL, NULL, neightbl_dump_info,
3895 0);
3896 rtnl_register(PF_UNSPEC, RTM_SETNEIGHTBL, neightbl_set, NULL, 0);
3897
3898 return 0;
3899}
3900
3901subsys_initcall(neigh_init);