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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#include <linux/slab.h>
19#include <linux/types.h>
20#include <linux/kernel.h>
21#include <linux/module.h>
22#include <linux/socket.h>
23#include <linux/netdevice.h>
24#include <linux/proc_fs.h>
25#ifdef CONFIG_SYSCTL
26#include <linux/sysctl.h>
27#endif
28#include <linux/times.h>
29#include <net/net_namespace.h>
30#include <net/neighbour.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
40#define NEIGH_DEBUG 1
41
42#define NEIGH_PRINTK(x...) printk(x)
43#define NEIGH_NOPRINTK(x...) do { ; } while(0)
44#define NEIGH_PRINTK1 NEIGH_NOPRINTK
45#define NEIGH_PRINTK2 NEIGH_NOPRINTK
46
47#if NEIGH_DEBUG >= 1
48#undef NEIGH_PRINTK1
49#define NEIGH_PRINTK1 NEIGH_PRINTK
50#endif
51#if NEIGH_DEBUG >= 2
52#undef NEIGH_PRINTK2
53#define NEIGH_PRINTK2 NEIGH_PRINTK
54#endif
55
56#define PNEIGH_HASHMASK 0xF
57
58static void neigh_timer_handler(unsigned long arg);
59static void __neigh_notify(struct neighbour *n, int type, int flags);
60static void neigh_update_notify(struct neighbour *neigh);
61static int pneigh_ifdown(struct neigh_table *tbl, struct net_device *dev);
62
63static struct neigh_table *neigh_tables;
64#ifdef CONFIG_PROC_FS
65static const struct file_operations neigh_stat_seq_fops;
66#endif
67
68/*
69 Neighbour hash table buckets are protected with rwlock tbl->lock.
70
71 - All the scans/updates to hash buckets MUST be made under this lock.
72 - NOTHING clever should be made under this lock: no callbacks
73 to protocol backends, no attempts to send something to network.
74 It will result in deadlocks, if backend/driver wants to use neighbour
75 cache.
76 - If the entry requires some non-trivial actions, increase
77 its reference count and release table lock.
78
79 Neighbour entries are protected:
80 - with reference count.
81 - with rwlock neigh->lock
82
83 Reference count prevents destruction.
84
85 neigh->lock mainly serializes ll address data and its validity state.
86 However, the same lock is used to protect another entry fields:
87 - timer
88 - resolution queue
89
90 Again, nothing clever shall be made under neigh->lock,
91 the most complicated procedure, which we allow is dev->hard_header.
92 It is supposed, that dev->hard_header is simplistic and does
93 not make callbacks to neighbour tables.
94
95 The last lock is neigh_tbl_lock. It is pure SMP lock, protecting
96 list of neighbour tables. This list is used only in process context,
97 */
98
99static DEFINE_RWLOCK(neigh_tbl_lock);
100
101static int neigh_blackhole(struct neighbour *neigh, struct sk_buff *skb)
102{
103 kfree_skb(skb);
104 return -ENETDOWN;
105}
106
107static void neigh_cleanup_and_release(struct neighbour *neigh)
108{
109 if (neigh->parms->neigh_cleanup)
110 neigh->parms->neigh_cleanup(neigh);
111
112 __neigh_notify(neigh, RTM_DELNEIGH, 0);
113 neigh_release(neigh);
114}
115
116/*
117 * It is random distribution in the interval (1/2)*base...(3/2)*base.
118 * It corresponds to default IPv6 settings and is not overridable,
119 * because it is really reasonable choice.
120 */
121
122unsigned long neigh_rand_reach_time(unsigned long base)
123{
124 return base ? (net_random() % base) + (base >> 1) : 0;
125}
126EXPORT_SYMBOL(neigh_rand_reach_time);
127
128
129static int neigh_forced_gc(struct neigh_table *tbl)
130{
131 int shrunk = 0;
132 int i;
133 struct neigh_hash_table *nht;
134
135 NEIGH_CACHE_STAT_INC(tbl, forced_gc_runs);
136
137 write_lock_bh(&tbl->lock);
138 nht = rcu_dereference_protected(tbl->nht,
139 lockdep_is_held(&tbl->lock));
140 for (i = 0; i < (1 << nht->hash_shift); i++) {
141 struct neighbour *n;
142 struct neighbour __rcu **np;
143
144 np = &nht->hash_buckets[i];
145 while ((n = rcu_dereference_protected(*np,
146 lockdep_is_held(&tbl->lock))) != NULL) {
147 /* Neighbour record may be discarded if:
148 * - nobody refers to it.
149 * - it is not permanent
150 */
151 write_lock(&n->lock);
152 if (atomic_read(&n->refcnt) == 1 &&
153 !(n->nud_state & NUD_PERMANENT)) {
154 rcu_assign_pointer(*np,
155 rcu_dereference_protected(n->next,
156 lockdep_is_held(&tbl->lock)));
157 n->dead = 1;
158 shrunk = 1;
159 write_unlock(&n->lock);
160 neigh_cleanup_and_release(n);
161 continue;
162 }
163 write_unlock(&n->lock);
164 np = &n->next;
165 }
166 }
167
168 tbl->last_flush = jiffies;
169
170 write_unlock_bh(&tbl->lock);
171
172 return shrunk;
173}
174
175static void neigh_add_timer(struct neighbour *n, unsigned long when)
176{
177 neigh_hold(n);
178 if (unlikely(mod_timer(&n->timer, when))) {
179 printk("NEIGH: BUG, double timer add, state is %x\n",
180 n->nud_state);
181 dump_stack();
182 }
183}
184
185static int neigh_del_timer(struct neighbour *n)
186{
187 if ((n->nud_state & NUD_IN_TIMER) &&
188 del_timer(&n->timer)) {
189 neigh_release(n);
190 return 1;
191 }
192 return 0;
193}
194
195static void pneigh_queue_purge(struct sk_buff_head *list)
196{
197 struct sk_buff *skb;
198
199 while ((skb = skb_dequeue(list)) != NULL) {
200 dev_put(skb->dev);
201 kfree_skb(skb);
202 }
203}
204
205static void neigh_flush_dev(struct neigh_table *tbl, struct net_device *dev)
206{
207 int i;
208 struct neigh_hash_table *nht;
209
210 nht = rcu_dereference_protected(tbl->nht,
211 lockdep_is_held(&tbl->lock));
212
213 for (i = 0; i < (1 << nht->hash_shift); i++) {
214 struct neighbour *n;
215 struct neighbour __rcu **np = &nht->hash_buckets[i];
216
217 while ((n = rcu_dereference_protected(*np,
218 lockdep_is_held(&tbl->lock))) != NULL) {
219 if (dev && n->dev != dev) {
220 np = &n->next;
221 continue;
222 }
223 rcu_assign_pointer(*np,
224 rcu_dereference_protected(n->next,
225 lockdep_is_held(&tbl->lock)));
226 write_lock(&n->lock);
227 neigh_del_timer(n);
228 n->dead = 1;
229
230 if (atomic_read(&n->refcnt) != 1) {
231 /* The most unpleasant situation.
232 We must destroy neighbour entry,
233 but someone still uses it.
234
235 The destroy will be delayed until
236 the last user releases us, but
237 we must kill timers etc. and move
238 it to safe state.
239 */
240 skb_queue_purge(&n->arp_queue);
241 n->output = neigh_blackhole;
242 if (n->nud_state & NUD_VALID)
243 n->nud_state = NUD_NOARP;
244 else
245 n->nud_state = NUD_NONE;
246 NEIGH_PRINTK2("neigh %p is stray.\n", n);
247 }
248 write_unlock(&n->lock);
249 neigh_cleanup_and_release(n);
250 }
251 }
252}
253
254void neigh_changeaddr(struct neigh_table *tbl, struct net_device *dev)
255{
256 write_lock_bh(&tbl->lock);
257 neigh_flush_dev(tbl, dev);
258 write_unlock_bh(&tbl->lock);
259}
260EXPORT_SYMBOL(neigh_changeaddr);
261
262int neigh_ifdown(struct neigh_table *tbl, struct net_device *dev)
263{
264 write_lock_bh(&tbl->lock);
265 neigh_flush_dev(tbl, dev);
266 pneigh_ifdown(tbl, dev);
267 write_unlock_bh(&tbl->lock);
268
269 del_timer_sync(&tbl->proxy_timer);
270 pneigh_queue_purge(&tbl->proxy_queue);
271 return 0;
272}
273EXPORT_SYMBOL(neigh_ifdown);
274
275static struct neighbour *neigh_alloc(struct neigh_table *tbl)
276{
277 struct neighbour *n = NULL;
278 unsigned long now = jiffies;
279 int entries;
280
281 entries = atomic_inc_return(&tbl->entries) - 1;
282 if (entries >= tbl->gc_thresh3 ||
283 (entries >= tbl->gc_thresh2 &&
284 time_after(now, tbl->last_flush + 5 * HZ))) {
285 if (!neigh_forced_gc(tbl) &&
286 entries >= tbl->gc_thresh3)
287 goto out_entries;
288 }
289
290 n = kmem_cache_zalloc(tbl->kmem_cachep, GFP_ATOMIC);
291 if (!n)
292 goto out_entries;
293
294 skb_queue_head_init(&n->arp_queue);
295 rwlock_init(&n->lock);
296 seqlock_init(&n->ha_lock);
297 n->updated = n->used = now;
298 n->nud_state = NUD_NONE;
299 n->output = neigh_blackhole;
300 seqlock_init(&n->hh.hh_lock);
301 n->parms = neigh_parms_clone(&tbl->parms);
302 setup_timer(&n->timer, neigh_timer_handler, (unsigned long)n);
303
304 NEIGH_CACHE_STAT_INC(tbl, allocs);
305 n->tbl = tbl;
306 atomic_set(&n->refcnt, 1);
307 n->dead = 1;
308out:
309 return n;
310
311out_entries:
312 atomic_dec(&tbl->entries);
313 goto out;
314}
315
316static struct neigh_hash_table *neigh_hash_alloc(unsigned int shift)
317{
318 size_t size = (1 << shift) * sizeof(struct neighbour *);
319 struct neigh_hash_table *ret;
320 struct neighbour __rcu **buckets;
321
322 ret = kmalloc(sizeof(*ret), GFP_ATOMIC);
323 if (!ret)
324 return NULL;
325 if (size <= PAGE_SIZE)
326 buckets = kzalloc(size, GFP_ATOMIC);
327 else
328 buckets = (struct neighbour __rcu **)
329 __get_free_pages(GFP_ATOMIC | __GFP_ZERO,
330 get_order(size));
331 if (!buckets) {
332 kfree(ret);
333 return NULL;
334 }
335 ret->hash_buckets = buckets;
336 ret->hash_shift = shift;
337 get_random_bytes(&ret->hash_rnd, sizeof(ret->hash_rnd));
338 ret->hash_rnd |= 1;
339 return ret;
340}
341
342static void neigh_hash_free_rcu(struct rcu_head *head)
343{
344 struct neigh_hash_table *nht = container_of(head,
345 struct neigh_hash_table,
346 rcu);
347 size_t size = (1 << nht->hash_shift) * sizeof(struct neighbour *);
348 struct neighbour __rcu **buckets = nht->hash_buckets;
349
350 if (size <= PAGE_SIZE)
351 kfree(buckets);
352 else
353 free_pages((unsigned long)buckets, get_order(size));
354 kfree(nht);
355}
356
357static struct neigh_hash_table *neigh_hash_grow(struct neigh_table *tbl,
358 unsigned long new_shift)
359{
360 unsigned int i, hash;
361 struct neigh_hash_table *new_nht, *old_nht;
362
363 NEIGH_CACHE_STAT_INC(tbl, hash_grows);
364
365 old_nht = rcu_dereference_protected(tbl->nht,
366 lockdep_is_held(&tbl->lock));
367 new_nht = neigh_hash_alloc(new_shift);
368 if (!new_nht)
369 return old_nht;
370
371 for (i = 0; i < (1 << old_nht->hash_shift); i++) {
372 struct neighbour *n, *next;
373
374 for (n = rcu_dereference_protected(old_nht->hash_buckets[i],
375 lockdep_is_held(&tbl->lock));
376 n != NULL;
377 n = next) {
378 hash = tbl->hash(n->primary_key, n->dev,
379 new_nht->hash_rnd);
380
381 hash >>= (32 - new_nht->hash_shift);
382 next = rcu_dereference_protected(n->next,
383 lockdep_is_held(&tbl->lock));
384
385 rcu_assign_pointer(n->next,
386 rcu_dereference_protected(
387 new_nht->hash_buckets[hash],
388 lockdep_is_held(&tbl->lock)));
389 rcu_assign_pointer(new_nht->hash_buckets[hash], n);
390 }
391 }
392
393 rcu_assign_pointer(tbl->nht, new_nht);
394 call_rcu(&old_nht->rcu, neigh_hash_free_rcu);
395 return new_nht;
396}
397
398struct neighbour *neigh_lookup(struct neigh_table *tbl, const void *pkey,
399 struct net_device *dev)
400{
401 struct neighbour *n;
402 int key_len = tbl->key_len;
403 u32 hash_val;
404 struct neigh_hash_table *nht;
405
406 NEIGH_CACHE_STAT_INC(tbl, lookups);
407
408 rcu_read_lock_bh();
409 nht = rcu_dereference_bh(tbl->nht);
410 hash_val = tbl->hash(pkey, dev, nht->hash_rnd) >> (32 - nht->hash_shift);
411
412 for (n = rcu_dereference_bh(nht->hash_buckets[hash_val]);
413 n != NULL;
414 n = rcu_dereference_bh(n->next)) {
415 if (dev == n->dev && !memcmp(n->primary_key, pkey, key_len)) {
416 if (!atomic_inc_not_zero(&n->refcnt))
417 n = NULL;
418 NEIGH_CACHE_STAT_INC(tbl, hits);
419 break;
420 }
421 }
422
423 rcu_read_unlock_bh();
424 return n;
425}
426EXPORT_SYMBOL(neigh_lookup);
427
428struct neighbour *neigh_lookup_nodev(struct neigh_table *tbl, struct net *net,
429 const void *pkey)
430{
431 struct neighbour *n;
432 int key_len = tbl->key_len;
433 u32 hash_val;
434 struct neigh_hash_table *nht;
435
436 NEIGH_CACHE_STAT_INC(tbl, lookups);
437
438 rcu_read_lock_bh();
439 nht = rcu_dereference_bh(tbl->nht);
440 hash_val = tbl->hash(pkey, NULL, nht->hash_rnd) >> (32 - nht->hash_shift);
441
442 for (n = rcu_dereference_bh(nht->hash_buckets[hash_val]);
443 n != NULL;
444 n = rcu_dereference_bh(n->next)) {
445 if (!memcmp(n->primary_key, pkey, key_len) &&
446 net_eq(dev_net(n->dev), net)) {
447 if (!atomic_inc_not_zero(&n->refcnt))
448 n = NULL;
449 NEIGH_CACHE_STAT_INC(tbl, hits);
450 break;
451 }
452 }
453
454 rcu_read_unlock_bh();
455 return n;
456}
457EXPORT_SYMBOL(neigh_lookup_nodev);
458
459struct neighbour *neigh_create(struct neigh_table *tbl, const void *pkey,
460 struct net_device *dev)
461{
462 u32 hash_val;
463 int key_len = tbl->key_len;
464 int error;
465 struct neighbour *n1, *rc, *n = neigh_alloc(tbl);
466 struct neigh_hash_table *nht;
467
468 if (!n) {
469 rc = ERR_PTR(-ENOBUFS);
470 goto out;
471 }
472
473 memcpy(n->primary_key, pkey, key_len);
474 n->dev = dev;
475 dev_hold(dev);
476
477 /* Protocol specific setup. */
478 if (tbl->constructor && (error = tbl->constructor(n)) < 0) {
479 rc = ERR_PTR(error);
480 goto out_neigh_release;
481 }
482
483 /* Device specific setup. */
484 if (n->parms->neigh_setup &&
485 (error = n->parms->neigh_setup(n)) < 0) {
486 rc = ERR_PTR(error);
487 goto out_neigh_release;
488 }
489
490 n->confirmed = jiffies - (n->parms->base_reachable_time << 1);
491
492 write_lock_bh(&tbl->lock);
493 nht = rcu_dereference_protected(tbl->nht,
494 lockdep_is_held(&tbl->lock));
495
496 if (atomic_read(&tbl->entries) > (1 << nht->hash_shift))
497 nht = neigh_hash_grow(tbl, nht->hash_shift + 1);
498
499 hash_val = tbl->hash(pkey, dev, nht->hash_rnd) >> (32 - nht->hash_shift);
500
501 if (n->parms->dead) {
502 rc = ERR_PTR(-EINVAL);
503 goto out_tbl_unlock;
504 }
505
506 for (n1 = rcu_dereference_protected(nht->hash_buckets[hash_val],
507 lockdep_is_held(&tbl->lock));
508 n1 != NULL;
509 n1 = rcu_dereference_protected(n1->next,
510 lockdep_is_held(&tbl->lock))) {
511 if (dev == n1->dev && !memcmp(n1->primary_key, pkey, key_len)) {
512 neigh_hold(n1);
513 rc = n1;
514 goto out_tbl_unlock;
515 }
516 }
517
518 n->dead = 0;
519 neigh_hold(n);
520 rcu_assign_pointer(n->next,
521 rcu_dereference_protected(nht->hash_buckets[hash_val],
522 lockdep_is_held(&tbl->lock)));
523 rcu_assign_pointer(nht->hash_buckets[hash_val], n);
524 write_unlock_bh(&tbl->lock);
525 NEIGH_PRINTK2("neigh %p is created.\n", n);
526 rc = n;
527out:
528 return rc;
529out_tbl_unlock:
530 write_unlock_bh(&tbl->lock);
531out_neigh_release:
532 neigh_release(n);
533 goto out;
534}
535EXPORT_SYMBOL(neigh_create);
536
537static u32 pneigh_hash(const void *pkey, int key_len)
538{
539 u32 hash_val = *(u32 *)(pkey + key_len - 4);
540 hash_val ^= (hash_val >> 16);
541 hash_val ^= hash_val >> 8;
542 hash_val ^= hash_val >> 4;
543 hash_val &= PNEIGH_HASHMASK;
544 return hash_val;
545}
546
547static struct pneigh_entry *__pneigh_lookup_1(struct pneigh_entry *n,
548 struct net *net,
549 const void *pkey,
550 int key_len,
551 struct net_device *dev)
552{
553 while (n) {
554 if (!memcmp(n->key, pkey, key_len) &&
555 net_eq(pneigh_net(n), net) &&
556 (n->dev == dev || !n->dev))
557 return n;
558 n = n->next;
559 }
560 return NULL;
561}
562
563struct pneigh_entry *__pneigh_lookup(struct neigh_table *tbl,
564 struct net *net, const void *pkey, struct net_device *dev)
565{
566 int key_len = tbl->key_len;
567 u32 hash_val = pneigh_hash(pkey, key_len);
568
569 return __pneigh_lookup_1(tbl->phash_buckets[hash_val],
570 net, pkey, key_len, dev);
571}
572EXPORT_SYMBOL_GPL(__pneigh_lookup);
573
574struct pneigh_entry * pneigh_lookup(struct neigh_table *tbl,
575 struct net *net, const void *pkey,
576 struct net_device *dev, int creat)
577{
578 struct pneigh_entry *n;
579 int key_len = tbl->key_len;
580 u32 hash_val = pneigh_hash(pkey, key_len);
581
582 read_lock_bh(&tbl->lock);
583 n = __pneigh_lookup_1(tbl->phash_buckets[hash_val],
584 net, pkey, key_len, dev);
585 read_unlock_bh(&tbl->lock);
586
587 if (n || !creat)
588 goto out;
589
590 ASSERT_RTNL();
591
592 n = kmalloc(sizeof(*n) + key_len, GFP_KERNEL);
593 if (!n)
594 goto out;
595
596 write_pnet(&n->net, hold_net(net));
597 memcpy(n->key, pkey, key_len);
598 n->dev = dev;
599 if (dev)
600 dev_hold(dev);
601
602 if (tbl->pconstructor && tbl->pconstructor(n)) {
603 if (dev)
604 dev_put(dev);
605 release_net(net);
606 kfree(n);
607 n = NULL;
608 goto out;
609 }
610
611 write_lock_bh(&tbl->lock);
612 n->next = tbl->phash_buckets[hash_val];
613 tbl->phash_buckets[hash_val] = n;
614 write_unlock_bh(&tbl->lock);
615out:
616 return n;
617}
618EXPORT_SYMBOL(pneigh_lookup);
619
620
621int pneigh_delete(struct neigh_table *tbl, struct net *net, const void *pkey,
622 struct net_device *dev)
623{
624 struct pneigh_entry *n, **np;
625 int key_len = tbl->key_len;
626 u32 hash_val = pneigh_hash(pkey, key_len);
627
628 write_lock_bh(&tbl->lock);
629 for (np = &tbl->phash_buckets[hash_val]; (n = *np) != NULL;
630 np = &n->next) {
631 if (!memcmp(n->key, pkey, key_len) && n->dev == dev &&
632 net_eq(pneigh_net(n), net)) {
633 *np = n->next;
634 write_unlock_bh(&tbl->lock);
635 if (tbl->pdestructor)
636 tbl->pdestructor(n);
637 if (n->dev)
638 dev_put(n->dev);
639 release_net(pneigh_net(n));
640 kfree(n);
641 return 0;
642 }
643 }
644 write_unlock_bh(&tbl->lock);
645 return -ENOENT;
646}
647
648static int pneigh_ifdown(struct neigh_table *tbl, struct net_device *dev)
649{
650 struct pneigh_entry *n, **np;
651 u32 h;
652
653 for (h = 0; h <= PNEIGH_HASHMASK; h++) {
654 np = &tbl->phash_buckets[h];
655 while ((n = *np) != NULL) {
656 if (!dev || n->dev == dev) {
657 *np = n->next;
658 if (tbl->pdestructor)
659 tbl->pdestructor(n);
660 if (n->dev)
661 dev_put(n->dev);
662 release_net(pneigh_net(n));
663 kfree(n);
664 continue;
665 }
666 np = &n->next;
667 }
668 }
669 return -ENOENT;
670}
671
672static void neigh_parms_destroy(struct neigh_parms *parms);
673
674static inline void neigh_parms_put(struct neigh_parms *parms)
675{
676 if (atomic_dec_and_test(&parms->refcnt))
677 neigh_parms_destroy(parms);
678}
679
680static void neigh_destroy_rcu(struct rcu_head *head)
681{
682 struct neighbour *neigh = container_of(head, struct neighbour, rcu);
683
684 kmem_cache_free(neigh->tbl->kmem_cachep, neigh);
685}
686/*
687 * neighbour must already be out of the table;
688 *
689 */
690void neigh_destroy(struct neighbour *neigh)
691{
692 NEIGH_CACHE_STAT_INC(neigh->tbl, destroys);
693
694 if (!neigh->dead) {
695 printk(KERN_WARNING
696 "Destroying alive neighbour %p\n", neigh);
697 dump_stack();
698 return;
699 }
700
701 if (neigh_del_timer(neigh))
702 printk(KERN_WARNING "Impossible event.\n");
703
704 skb_queue_purge(&neigh->arp_queue);
705
706 dev_put(neigh->dev);
707 neigh_parms_put(neigh->parms);
708
709 NEIGH_PRINTK2("neigh %p is destroyed.\n", neigh);
710
711 atomic_dec(&neigh->tbl->entries);
712 call_rcu(&neigh->rcu, neigh_destroy_rcu);
713}
714EXPORT_SYMBOL(neigh_destroy);
715
716/* Neighbour state is suspicious;
717 disable fast path.
718
719 Called with write_locked neigh.
720 */
721static void neigh_suspect(struct neighbour *neigh)
722{
723 NEIGH_PRINTK2("neigh %p is suspected.\n", neigh);
724
725 neigh->output = neigh->ops->output;
726}
727
728/* Neighbour state is OK;
729 enable fast path.
730
731 Called with write_locked neigh.
732 */
733static void neigh_connect(struct neighbour *neigh)
734{
735 NEIGH_PRINTK2("neigh %p is connected.\n", neigh);
736
737 neigh->output = neigh->ops->connected_output;
738}
739
740static void neigh_periodic_work(struct work_struct *work)
741{
742 struct neigh_table *tbl = container_of(work, struct neigh_table, gc_work.work);
743 struct neighbour *n;
744 struct neighbour __rcu **np;
745 unsigned int i;
746 struct neigh_hash_table *nht;
747
748 NEIGH_CACHE_STAT_INC(tbl, periodic_gc_runs);
749
750 write_lock_bh(&tbl->lock);
751 nht = rcu_dereference_protected(tbl->nht,
752 lockdep_is_held(&tbl->lock));
753
754 /*
755 * periodically recompute ReachableTime from random function
756 */
757
758 if (time_after(jiffies, tbl->last_rand + 300 * HZ)) {
759 struct neigh_parms *p;
760 tbl->last_rand = jiffies;
761 for (p = &tbl->parms; p; p = p->next)
762 p->reachable_time =
763 neigh_rand_reach_time(p->base_reachable_time);
764 }
765
766 for (i = 0 ; i < (1 << nht->hash_shift); i++) {
767 np = &nht->hash_buckets[i];
768
769 while ((n = rcu_dereference_protected(*np,
770 lockdep_is_held(&tbl->lock))) != NULL) {
771 unsigned int state;
772
773 write_lock(&n->lock);
774
775 state = n->nud_state;
776 if (state & (NUD_PERMANENT | NUD_IN_TIMER)) {
777 write_unlock(&n->lock);
778 goto next_elt;
779 }
780
781 if (time_before(n->used, n->confirmed))
782 n->used = n->confirmed;
783
784 if (atomic_read(&n->refcnt) == 1 &&
785 (state == NUD_FAILED ||
786 time_after(jiffies, n->used + n->parms->gc_staletime))) {
787 *np = n->next;
788 n->dead = 1;
789 write_unlock(&n->lock);
790 neigh_cleanup_and_release(n);
791 continue;
792 }
793 write_unlock(&n->lock);
794
795next_elt:
796 np = &n->next;
797 }
798 /*
799 * It's fine to release lock here, even if hash table
800 * grows while we are preempted.
801 */
802 write_unlock_bh(&tbl->lock);
803 cond_resched();
804 write_lock_bh(&tbl->lock);
805 }
806 /* Cycle through all hash buckets every base_reachable_time/2 ticks.
807 * ARP entry timeouts range from 1/2 base_reachable_time to 3/2
808 * base_reachable_time.
809 */
810 schedule_delayed_work(&tbl->gc_work,
811 tbl->parms.base_reachable_time >> 1);
812 write_unlock_bh(&tbl->lock);
813}
814
815static __inline__ int neigh_max_probes(struct neighbour *n)
816{
817 struct neigh_parms *p = n->parms;
818 return (n->nud_state & NUD_PROBE) ?
819 p->ucast_probes :
820 p->ucast_probes + p->app_probes + p->mcast_probes;
821}
822
823static void neigh_invalidate(struct neighbour *neigh)
824 __releases(neigh->lock)
825 __acquires(neigh->lock)
826{
827 struct sk_buff *skb;
828
829 NEIGH_CACHE_STAT_INC(neigh->tbl, res_failed);
830 NEIGH_PRINTK2("neigh %p is failed.\n", neigh);
831 neigh->updated = jiffies;
832
833 /* It is very thin place. report_unreachable is very complicated
834 routine. Particularly, it can hit the same neighbour entry!
835
836 So that, we try to be accurate and avoid dead loop. --ANK
837 */
838 while (neigh->nud_state == NUD_FAILED &&
839 (skb = __skb_dequeue(&neigh->arp_queue)) != NULL) {
840 write_unlock(&neigh->lock);
841 neigh->ops->error_report(neigh, skb);
842 write_lock(&neigh->lock);
843 }
844 skb_queue_purge(&neigh->arp_queue);
845}
846
847/* Called when a timer expires for a neighbour entry. */
848
849static void neigh_timer_handler(unsigned long arg)
850{
851 unsigned long now, next;
852 struct neighbour *neigh = (struct neighbour *)arg;
853 unsigned state;
854 int notify = 0;
855
856 write_lock(&neigh->lock);
857
858 state = neigh->nud_state;
859 now = jiffies;
860 next = now + HZ;
861
862 if (!(state & NUD_IN_TIMER)) {
863#ifndef CONFIG_SMP
864 printk(KERN_WARNING "neigh: timer & !nud_in_timer\n");
865#endif
866 goto out;
867 }
868
869 if (state & NUD_REACHABLE) {
870 if (time_before_eq(now,
871 neigh->confirmed + neigh->parms->reachable_time)) {
872 NEIGH_PRINTK2("neigh %p is still alive.\n", neigh);
873 next = neigh->confirmed + neigh->parms->reachable_time;
874 } else if (time_before_eq(now,
875 neigh->used + neigh->parms->delay_probe_time)) {
876 NEIGH_PRINTK2("neigh %p is delayed.\n", neigh);
877 neigh->nud_state = NUD_DELAY;
878 neigh->updated = jiffies;
879 neigh_suspect(neigh);
880 next = now + neigh->parms->delay_probe_time;
881 } else {
882 NEIGH_PRINTK2("neigh %p is suspected.\n", neigh);
883 neigh->nud_state = NUD_STALE;
884 neigh->updated = jiffies;
885 neigh_suspect(neigh);
886 notify = 1;
887 }
888 } else if (state & NUD_DELAY) {
889 if (time_before_eq(now,
890 neigh->confirmed + neigh->parms->delay_probe_time)) {
891 NEIGH_PRINTK2("neigh %p is now reachable.\n", neigh);
892 neigh->nud_state = NUD_REACHABLE;
893 neigh->updated = jiffies;
894 neigh_connect(neigh);
895 notify = 1;
896 next = neigh->confirmed + neigh->parms->reachable_time;
897 } else {
898 NEIGH_PRINTK2("neigh %p is probed.\n", neigh);
899 neigh->nud_state = NUD_PROBE;
900 neigh->updated = jiffies;
901 atomic_set(&neigh->probes, 0);
902 next = now + neigh->parms->retrans_time;
903 }
904 } else {
905 /* NUD_PROBE|NUD_INCOMPLETE */
906 next = now + neigh->parms->retrans_time;
907 }
908
909 if ((neigh->nud_state & (NUD_INCOMPLETE | NUD_PROBE)) &&
910 atomic_read(&neigh->probes) >= neigh_max_probes(neigh)) {
911 neigh->nud_state = NUD_FAILED;
912 notify = 1;
913 neigh_invalidate(neigh);
914 }
915
916 if (neigh->nud_state & NUD_IN_TIMER) {
917 if (time_before(next, jiffies + HZ/2))
918 next = jiffies + HZ/2;
919 if (!mod_timer(&neigh->timer, next))
920 neigh_hold(neigh);
921 }
922 if (neigh->nud_state & (NUD_INCOMPLETE | NUD_PROBE)) {
923 struct sk_buff *skb = skb_peek(&neigh->arp_queue);
924 /* keep skb alive even if arp_queue overflows */
925 if (skb)
926 skb = skb_copy(skb, GFP_ATOMIC);
927 write_unlock(&neigh->lock);
928 neigh->ops->solicit(neigh, skb);
929 atomic_inc(&neigh->probes);
930 kfree_skb(skb);
931 } else {
932out:
933 write_unlock(&neigh->lock);
934 }
935
936 if (notify)
937 neigh_update_notify(neigh);
938
939 neigh_release(neigh);
940}
941
942int __neigh_event_send(struct neighbour *neigh, struct sk_buff *skb)
943{
944 int rc;
945 unsigned long now;
946
947 write_lock_bh(&neigh->lock);
948
949 rc = 0;
950 if (neigh->nud_state & (NUD_CONNECTED | NUD_DELAY | NUD_PROBE))
951 goto out_unlock_bh;
952
953 now = jiffies;
954
955 if (!(neigh->nud_state & (NUD_STALE | NUD_INCOMPLETE))) {
956 if (neigh->parms->mcast_probes + neigh->parms->app_probes) {
957 atomic_set(&neigh->probes, neigh->parms->ucast_probes);
958 neigh->nud_state = NUD_INCOMPLETE;
959 neigh->updated = jiffies;
960 neigh_add_timer(neigh, now + 1);
961 } else {
962 neigh->nud_state = NUD_FAILED;
963 neigh->updated = jiffies;
964 write_unlock_bh(&neigh->lock);
965
966 kfree_skb(skb);
967 return 1;
968 }
969 } else if (neigh->nud_state & NUD_STALE) {
970 NEIGH_PRINTK2("neigh %p is delayed.\n", neigh);
971 neigh->nud_state = NUD_DELAY;
972 neigh->updated = jiffies;
973 neigh_add_timer(neigh,
974 jiffies + neigh->parms->delay_probe_time);
975 }
976
977 if (neigh->nud_state == NUD_INCOMPLETE) {
978 if (skb) {
979 if (skb_queue_len(&neigh->arp_queue) >=
980 neigh->parms->queue_len) {
981 struct sk_buff *buff;
982 buff = __skb_dequeue(&neigh->arp_queue);
983 kfree_skb(buff);
984 NEIGH_CACHE_STAT_INC(neigh->tbl, unres_discards);
985 }
986 skb_dst_force(skb);
987 __skb_queue_tail(&neigh->arp_queue, skb);
988 }
989 rc = 1;
990 }
991out_unlock_bh:
992 write_unlock_bh(&neigh->lock);
993 return rc;
994}
995EXPORT_SYMBOL(__neigh_event_send);
996
997static void neigh_update_hhs(struct neighbour *neigh)
998{
999 struct hh_cache *hh;
1000 void (*update)(struct hh_cache*, const struct net_device*, const unsigned char *)
1001 = NULL;
1002
1003 if (neigh->dev->header_ops)
1004 update = neigh->dev->header_ops->cache_update;
1005
1006 if (update) {
1007 hh = &neigh->hh;
1008 if (hh->hh_len) {
1009 write_seqlock_bh(&hh->hh_lock);
1010 update(hh, neigh->dev, neigh->ha);
1011 write_sequnlock_bh(&hh->hh_lock);
1012 }
1013 }
1014}
1015
1016
1017
1018/* Generic update routine.
1019 -- lladdr is new lladdr or NULL, if it is not supplied.
1020 -- new is new state.
1021 -- flags
1022 NEIGH_UPDATE_F_OVERRIDE allows to override existing lladdr,
1023 if it is different.
1024 NEIGH_UPDATE_F_WEAK_OVERRIDE will suspect existing "connected"
1025 lladdr instead of overriding it
1026 if it is different.
1027 It also allows to retain current state
1028 if lladdr is unchanged.
1029 NEIGH_UPDATE_F_ADMIN means that the change is administrative.
1030
1031 NEIGH_UPDATE_F_OVERRIDE_ISROUTER allows to override existing
1032 NTF_ROUTER flag.
1033 NEIGH_UPDATE_F_ISROUTER indicates if the neighbour is known as
1034 a router.
1035
1036 Caller MUST hold reference count on the entry.
1037 */
1038
1039int neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new,
1040 u32 flags)
1041{
1042 u8 old;
1043 int err;
1044 int notify = 0;
1045 struct net_device *dev;
1046 int update_isrouter = 0;
1047
1048 write_lock_bh(&neigh->lock);
1049
1050 dev = neigh->dev;
1051 old = neigh->nud_state;
1052 err = -EPERM;
1053
1054 if (!(flags & NEIGH_UPDATE_F_ADMIN) &&
1055 (old & (NUD_NOARP | NUD_PERMANENT)))
1056 goto out;
1057
1058 if (!(new & NUD_VALID)) {
1059 neigh_del_timer(neigh);
1060 if (old & NUD_CONNECTED)
1061 neigh_suspect(neigh);
1062 neigh->nud_state = new;
1063 err = 0;
1064 notify = old & NUD_VALID;
1065 if ((old & (NUD_INCOMPLETE | NUD_PROBE)) &&
1066 (new & NUD_FAILED)) {
1067 neigh_invalidate(neigh);
1068 notify = 1;
1069 }
1070 goto out;
1071 }
1072
1073 /* Compare new lladdr with cached one */
1074 if (!dev->addr_len) {
1075 /* First case: device needs no address. */
1076 lladdr = neigh->ha;
1077 } else if (lladdr) {
1078 /* The second case: if something is already cached
1079 and a new address is proposed:
1080 - compare new & old
1081 - if they are different, check override flag
1082 */
1083 if ((old & NUD_VALID) &&
1084 !memcmp(lladdr, neigh->ha, dev->addr_len))
1085 lladdr = neigh->ha;
1086 } else {
1087 /* No address is supplied; if we know something,
1088 use it, otherwise discard the request.
1089 */
1090 err = -EINVAL;
1091 if (!(old & NUD_VALID))
1092 goto out;
1093 lladdr = neigh->ha;
1094 }
1095
1096 if (new & NUD_CONNECTED)
1097 neigh->confirmed = jiffies;
1098 neigh->updated = jiffies;
1099
1100 /* If entry was valid and address is not changed,
1101 do not change entry state, if new one is STALE.
1102 */
1103 err = 0;
1104 update_isrouter = flags & NEIGH_UPDATE_F_OVERRIDE_ISROUTER;
1105 if (old & NUD_VALID) {
1106 if (lladdr != neigh->ha && !(flags & NEIGH_UPDATE_F_OVERRIDE)) {
1107 update_isrouter = 0;
1108 if ((flags & NEIGH_UPDATE_F_WEAK_OVERRIDE) &&
1109 (old & NUD_CONNECTED)) {
1110 lladdr = neigh->ha;
1111 new = NUD_STALE;
1112 } else
1113 goto out;
1114 } else {
1115 if (lladdr == neigh->ha && new == NUD_STALE &&
1116 ((flags & NEIGH_UPDATE_F_WEAK_OVERRIDE) ||
1117 (old & NUD_CONNECTED))
1118 )
1119 new = old;
1120 }
1121 }
1122
1123 if (new != old) {
1124 neigh_del_timer(neigh);
1125 if (new & NUD_IN_TIMER)
1126 neigh_add_timer(neigh, (jiffies +
1127 ((new & NUD_REACHABLE) ?
1128 neigh->parms->reachable_time :
1129 0)));
1130 neigh->nud_state = new;
1131 }
1132
1133 if (lladdr != neigh->ha) {
1134 write_seqlock(&neigh->ha_lock);
1135 memcpy(&neigh->ha, lladdr, dev->addr_len);
1136 write_sequnlock(&neigh->ha_lock);
1137 neigh_update_hhs(neigh);
1138 if (!(new & NUD_CONNECTED))
1139 neigh->confirmed = jiffies -
1140 (neigh->parms->base_reachable_time << 1);
1141 notify = 1;
1142 }
1143 if (new == old)
1144 goto out;
1145 if (new & NUD_CONNECTED)
1146 neigh_connect(neigh);
1147 else
1148 neigh_suspect(neigh);
1149 if (!(old & NUD_VALID)) {
1150 struct sk_buff *skb;
1151
1152 /* Again: avoid dead loop if something went wrong */
1153
1154 while (neigh->nud_state & NUD_VALID &&
1155 (skb = __skb_dequeue(&neigh->arp_queue)) != NULL) {
1156 struct dst_entry *dst = skb_dst(skb);
1157 struct neighbour *n2, *n1 = neigh;
1158 write_unlock_bh(&neigh->lock);
1159 /* On shaper/eql skb->dst->neighbour != neigh :( */
1160 if (dst && (n2 = dst_get_neighbour(dst)) != NULL)
1161 n1 = n2;
1162 n1->output(n1, skb);
1163 write_lock_bh(&neigh->lock);
1164 }
1165 skb_queue_purge(&neigh->arp_queue);
1166 }
1167out:
1168 if (update_isrouter) {
1169 neigh->flags = (flags & NEIGH_UPDATE_F_ISROUTER) ?
1170 (neigh->flags | NTF_ROUTER) :
1171 (neigh->flags & ~NTF_ROUTER);
1172 }
1173 write_unlock_bh(&neigh->lock);
1174
1175 if (notify)
1176 neigh_update_notify(neigh);
1177
1178 return err;
1179}
1180EXPORT_SYMBOL(neigh_update);
1181
1182struct neighbour *neigh_event_ns(struct neigh_table *tbl,
1183 u8 *lladdr, void *saddr,
1184 struct net_device *dev)
1185{
1186 struct neighbour *neigh = __neigh_lookup(tbl, saddr, dev,
1187 lladdr || !dev->addr_len);
1188 if (neigh)
1189 neigh_update(neigh, lladdr, NUD_STALE,
1190 NEIGH_UPDATE_F_OVERRIDE);
1191 return neigh;
1192}
1193EXPORT_SYMBOL(neigh_event_ns);
1194
1195/* called with read_lock_bh(&n->lock); */
1196static void neigh_hh_init(struct neighbour *n, struct dst_entry *dst)
1197{
1198 struct net_device *dev = dst->dev;
1199 __be16 prot = dst->ops->protocol;
1200 struct hh_cache *hh = &n->hh;
1201
1202 write_lock_bh(&n->lock);
1203
1204 /* Only one thread can come in here and initialize the
1205 * hh_cache entry.
1206 */
1207 if (!hh->hh_len)
1208 dev->header_ops->cache(n, hh, prot);
1209
1210 write_unlock_bh(&n->lock);
1211}
1212
1213/* This function can be used in contexts, where only old dev_queue_xmit
1214 * worked, f.e. if you want to override normal output path (eql, shaper),
1215 * but resolution is not made yet.
1216 */
1217
1218int neigh_compat_output(struct neighbour *neigh, struct sk_buff *skb)
1219{
1220 struct net_device *dev = skb->dev;
1221
1222 __skb_pull(skb, skb_network_offset(skb));
1223
1224 if (dev_hard_header(skb, dev, ntohs(skb->protocol), NULL, NULL,
1225 skb->len) < 0 &&
1226 dev->header_ops->rebuild(skb))
1227 return 0;
1228
1229 return dev_queue_xmit(skb);
1230}
1231EXPORT_SYMBOL(neigh_compat_output);
1232
1233/* Slow and careful. */
1234
1235int neigh_resolve_output(struct neighbour *neigh, struct sk_buff *skb)
1236{
1237 struct dst_entry *dst = skb_dst(skb);
1238 int rc = 0;
1239
1240 if (!dst)
1241 goto discard;
1242
1243 __skb_pull(skb, skb_network_offset(skb));
1244
1245 if (!neigh_event_send(neigh, skb)) {
1246 int err;
1247 struct net_device *dev = neigh->dev;
1248 unsigned int seq;
1249
1250 if (dev->header_ops->cache && !neigh->hh.hh_len)
1251 neigh_hh_init(neigh, dst);
1252
1253 do {
1254 seq = read_seqbegin(&neigh->ha_lock);
1255 err = dev_hard_header(skb, dev, ntohs(skb->protocol),
1256 neigh->ha, NULL, skb->len);
1257 } while (read_seqretry(&neigh->ha_lock, seq));
1258
1259 if (err >= 0)
1260 rc = dev_queue_xmit(skb);
1261 else
1262 goto out_kfree_skb;
1263 }
1264out:
1265 return rc;
1266discard:
1267 NEIGH_PRINTK1("neigh_resolve_output: dst=%p neigh=%p\n",
1268 dst, neigh);
1269out_kfree_skb:
1270 rc = -EINVAL;
1271 kfree_skb(skb);
1272 goto out;
1273}
1274EXPORT_SYMBOL(neigh_resolve_output);
1275
1276/* As fast as possible without hh cache */
1277
1278int neigh_connected_output(struct neighbour *neigh, struct sk_buff *skb)
1279{
1280 struct net_device *dev = neigh->dev;
1281 unsigned int seq;
1282 int err;
1283
1284 __skb_pull(skb, skb_network_offset(skb));
1285
1286 do {
1287 seq = read_seqbegin(&neigh->ha_lock);
1288 err = dev_hard_header(skb, dev, ntohs(skb->protocol),
1289 neigh->ha, NULL, skb->len);
1290 } while (read_seqretry(&neigh->ha_lock, seq));
1291
1292 if (err >= 0)
1293 err = dev_queue_xmit(skb);
1294 else {
1295 err = -EINVAL;
1296 kfree_skb(skb);
1297 }
1298 return err;
1299}
1300EXPORT_SYMBOL(neigh_connected_output);
1301
1302int neigh_direct_output(struct neighbour *neigh, struct sk_buff *skb)
1303{
1304 return dev_queue_xmit(skb);
1305}
1306EXPORT_SYMBOL(neigh_direct_output);
1307
1308static void neigh_proxy_process(unsigned long arg)
1309{
1310 struct neigh_table *tbl = (struct neigh_table *)arg;
1311 long sched_next = 0;
1312 unsigned long now = jiffies;
1313 struct sk_buff *skb, *n;
1314
1315 spin_lock(&tbl->proxy_queue.lock);
1316
1317 skb_queue_walk_safe(&tbl->proxy_queue, skb, n) {
1318 long tdif = NEIGH_CB(skb)->sched_next - now;
1319
1320 if (tdif <= 0) {
1321 struct net_device *dev = skb->dev;
1322
1323 __skb_unlink(skb, &tbl->proxy_queue);
1324 if (tbl->proxy_redo && netif_running(dev)) {
1325 rcu_read_lock();
1326 tbl->proxy_redo(skb);
1327 rcu_read_unlock();
1328 } else {
1329 kfree_skb(skb);
1330 }
1331
1332 dev_put(dev);
1333 } else if (!sched_next || tdif < sched_next)
1334 sched_next = tdif;
1335 }
1336 del_timer(&tbl->proxy_timer);
1337 if (sched_next)
1338 mod_timer(&tbl->proxy_timer, jiffies + sched_next);
1339 spin_unlock(&tbl->proxy_queue.lock);
1340}
1341
1342void pneigh_enqueue(struct neigh_table *tbl, struct neigh_parms *p,
1343 struct sk_buff *skb)
1344{
1345 unsigned long now = jiffies;
1346 unsigned long sched_next = now + (net_random() % p->proxy_delay);
1347
1348 if (tbl->proxy_queue.qlen > p->proxy_qlen) {
1349 kfree_skb(skb);
1350 return;
1351 }
1352
1353 NEIGH_CB(skb)->sched_next = sched_next;
1354 NEIGH_CB(skb)->flags |= LOCALLY_ENQUEUED;
1355
1356 spin_lock(&tbl->proxy_queue.lock);
1357 if (del_timer(&tbl->proxy_timer)) {
1358 if (time_before(tbl->proxy_timer.expires, sched_next))
1359 sched_next = tbl->proxy_timer.expires;
1360 }
1361 skb_dst_drop(skb);
1362 dev_hold(skb->dev);
1363 __skb_queue_tail(&tbl->proxy_queue, skb);
1364 mod_timer(&tbl->proxy_timer, sched_next);
1365 spin_unlock(&tbl->proxy_queue.lock);
1366}
1367EXPORT_SYMBOL(pneigh_enqueue);
1368
1369static inline struct neigh_parms *lookup_neigh_parms(struct neigh_table *tbl,
1370 struct net *net, int ifindex)
1371{
1372 struct neigh_parms *p;
1373
1374 for (p = &tbl->parms; p; p = p->next) {
1375 if ((p->dev && p->dev->ifindex == ifindex && net_eq(neigh_parms_net(p), net)) ||
1376 (!p->dev && !ifindex))
1377 return p;
1378 }
1379
1380 return NULL;
1381}
1382
1383struct neigh_parms *neigh_parms_alloc(struct net_device *dev,
1384 struct neigh_table *tbl)
1385{
1386 struct neigh_parms *p, *ref;
1387 struct net *net = dev_net(dev);
1388 const struct net_device_ops *ops = dev->netdev_ops;
1389
1390 ref = lookup_neigh_parms(tbl, net, 0);
1391 if (!ref)
1392 return NULL;
1393
1394 p = kmemdup(ref, sizeof(*p), GFP_KERNEL);
1395 if (p) {
1396 p->tbl = tbl;
1397 atomic_set(&p->refcnt, 1);
1398 p->reachable_time =
1399 neigh_rand_reach_time(p->base_reachable_time);
1400
1401 if (ops->ndo_neigh_setup && ops->ndo_neigh_setup(dev, p)) {
1402 kfree(p);
1403 return NULL;
1404 }
1405
1406 dev_hold(dev);
1407 p->dev = dev;
1408 write_pnet(&p->net, hold_net(net));
1409 p->sysctl_table = NULL;
1410 write_lock_bh(&tbl->lock);
1411 p->next = tbl->parms.next;
1412 tbl->parms.next = p;
1413 write_unlock_bh(&tbl->lock);
1414 }
1415 return p;
1416}
1417EXPORT_SYMBOL(neigh_parms_alloc);
1418
1419static void neigh_rcu_free_parms(struct rcu_head *head)
1420{
1421 struct neigh_parms *parms =
1422 container_of(head, struct neigh_parms, rcu_head);
1423
1424 neigh_parms_put(parms);
1425}
1426
1427void neigh_parms_release(struct neigh_table *tbl, struct neigh_parms *parms)
1428{
1429 struct neigh_parms **p;
1430
1431 if (!parms || parms == &tbl->parms)
1432 return;
1433 write_lock_bh(&tbl->lock);
1434 for (p = &tbl->parms.next; *p; p = &(*p)->next) {
1435 if (*p == parms) {
1436 *p = parms->next;
1437 parms->dead = 1;
1438 write_unlock_bh(&tbl->lock);
1439 if (parms->dev)
1440 dev_put(parms->dev);
1441 call_rcu(&parms->rcu_head, neigh_rcu_free_parms);
1442 return;
1443 }
1444 }
1445 write_unlock_bh(&tbl->lock);
1446 NEIGH_PRINTK1("neigh_parms_release: not found\n");
1447}
1448EXPORT_SYMBOL(neigh_parms_release);
1449
1450static void neigh_parms_destroy(struct neigh_parms *parms)
1451{
1452 release_net(neigh_parms_net(parms));
1453 kfree(parms);
1454}
1455
1456static struct lock_class_key neigh_table_proxy_queue_class;
1457
1458void neigh_table_init_no_netlink(struct neigh_table *tbl)
1459{
1460 unsigned long now = jiffies;
1461 unsigned long phsize;
1462
1463 write_pnet(&tbl->parms.net, &init_net);
1464 atomic_set(&tbl->parms.refcnt, 1);
1465 tbl->parms.reachable_time =
1466 neigh_rand_reach_time(tbl->parms.base_reachable_time);
1467
1468 if (!tbl->kmem_cachep)
1469 tbl->kmem_cachep =
1470 kmem_cache_create(tbl->id, tbl->entry_size, 0,
1471 SLAB_HWCACHE_ALIGN|SLAB_PANIC,
1472 NULL);
1473 tbl->stats = alloc_percpu(struct neigh_statistics);
1474 if (!tbl->stats)
1475 panic("cannot create neighbour cache statistics");
1476
1477#ifdef CONFIG_PROC_FS
1478 if (!proc_create_data(tbl->id, 0, init_net.proc_net_stat,
1479 &neigh_stat_seq_fops, tbl))
1480 panic("cannot create neighbour proc dir entry");
1481#endif
1482
1483 RCU_INIT_POINTER(tbl->nht, neigh_hash_alloc(3));
1484
1485 phsize = (PNEIGH_HASHMASK + 1) * sizeof(struct pneigh_entry *);
1486 tbl->phash_buckets = kzalloc(phsize, GFP_KERNEL);
1487
1488 if (!tbl->nht || !tbl->phash_buckets)
1489 panic("cannot allocate neighbour cache hashes");
1490
1491 rwlock_init(&tbl->lock);
1492 INIT_DELAYED_WORK_DEFERRABLE(&tbl->gc_work, neigh_periodic_work);
1493 schedule_delayed_work(&tbl->gc_work, tbl->parms.reachable_time);
1494 setup_timer(&tbl->proxy_timer, neigh_proxy_process, (unsigned long)tbl);
1495 skb_queue_head_init_class(&tbl->proxy_queue,
1496 &neigh_table_proxy_queue_class);
1497
1498 tbl->last_flush = now;
1499 tbl->last_rand = now + tbl->parms.reachable_time * 20;
1500}
1501EXPORT_SYMBOL(neigh_table_init_no_netlink);
1502
1503void neigh_table_init(struct neigh_table *tbl)
1504{
1505 struct neigh_table *tmp;
1506
1507 neigh_table_init_no_netlink(tbl);
1508 write_lock(&neigh_tbl_lock);
1509 for (tmp = neigh_tables; tmp; tmp = tmp->next) {
1510 if (tmp->family == tbl->family)
1511 break;
1512 }
1513 tbl->next = neigh_tables;
1514 neigh_tables = tbl;
1515 write_unlock(&neigh_tbl_lock);
1516
1517 if (unlikely(tmp)) {
1518 printk(KERN_ERR "NEIGH: Registering multiple tables for "
1519 "family %d\n", tbl->family);
1520 dump_stack();
1521 }
1522}
1523EXPORT_SYMBOL(neigh_table_init);
1524
1525int neigh_table_clear(struct neigh_table *tbl)
1526{
1527 struct neigh_table **tp;
1528
1529 /* It is not clean... Fix it to unload IPv6 module safely */
1530 cancel_delayed_work_sync(&tbl->gc_work);
1531 del_timer_sync(&tbl->proxy_timer);
1532 pneigh_queue_purge(&tbl->proxy_queue);
1533 neigh_ifdown(tbl, NULL);
1534 if (atomic_read(&tbl->entries))
1535 printk(KERN_CRIT "neighbour leakage\n");
1536 write_lock(&neigh_tbl_lock);
1537 for (tp = &neigh_tables; *tp; tp = &(*tp)->next) {
1538 if (*tp == tbl) {
1539 *tp = tbl->next;
1540 break;
1541 }
1542 }
1543 write_unlock(&neigh_tbl_lock);
1544
1545 call_rcu(&rcu_dereference_protected(tbl->nht, 1)->rcu,
1546 neigh_hash_free_rcu);
1547 tbl->nht = NULL;
1548
1549 kfree(tbl->phash_buckets);
1550 tbl->phash_buckets = NULL;
1551
1552 remove_proc_entry(tbl->id, init_net.proc_net_stat);
1553
1554 free_percpu(tbl->stats);
1555 tbl->stats = NULL;
1556
1557 kmem_cache_destroy(tbl->kmem_cachep);
1558 tbl->kmem_cachep = NULL;
1559
1560 return 0;
1561}
1562EXPORT_SYMBOL(neigh_table_clear);
1563
1564static int neigh_delete(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
1565{
1566 struct net *net = sock_net(skb->sk);
1567 struct ndmsg *ndm;
1568 struct nlattr *dst_attr;
1569 struct neigh_table *tbl;
1570 struct net_device *dev = NULL;
1571 int err = -EINVAL;
1572
1573 ASSERT_RTNL();
1574 if (nlmsg_len(nlh) < sizeof(*ndm))
1575 goto out;
1576
1577 dst_attr = nlmsg_find_attr(nlh, sizeof(*ndm), NDA_DST);
1578 if (dst_attr == NULL)
1579 goto out;
1580
1581 ndm = nlmsg_data(nlh);
1582 if (ndm->ndm_ifindex) {
1583 dev = __dev_get_by_index(net, ndm->ndm_ifindex);
1584 if (dev == NULL) {
1585 err = -ENODEV;
1586 goto out;
1587 }
1588 }
1589
1590 read_lock(&neigh_tbl_lock);
1591 for (tbl = neigh_tables; tbl; tbl = tbl->next) {
1592 struct neighbour *neigh;
1593
1594 if (tbl->family != ndm->ndm_family)
1595 continue;
1596 read_unlock(&neigh_tbl_lock);
1597
1598 if (nla_len(dst_attr) < tbl->key_len)
1599 goto out;
1600
1601 if (ndm->ndm_flags & NTF_PROXY) {
1602 err = pneigh_delete(tbl, net, nla_data(dst_attr), dev);
1603 goto out;
1604 }
1605
1606 if (dev == NULL)
1607 goto out;
1608
1609 neigh = neigh_lookup(tbl, nla_data(dst_attr), dev);
1610 if (neigh == NULL) {
1611 err = -ENOENT;
1612 goto out;
1613 }
1614
1615 err = neigh_update(neigh, NULL, NUD_FAILED,
1616 NEIGH_UPDATE_F_OVERRIDE |
1617 NEIGH_UPDATE_F_ADMIN);
1618 neigh_release(neigh);
1619 goto out;
1620 }
1621 read_unlock(&neigh_tbl_lock);
1622 err = -EAFNOSUPPORT;
1623
1624out:
1625 return err;
1626}
1627
1628static int neigh_add(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
1629{
1630 struct net *net = sock_net(skb->sk);
1631 struct ndmsg *ndm;
1632 struct nlattr *tb[NDA_MAX+1];
1633 struct neigh_table *tbl;
1634 struct net_device *dev = NULL;
1635 int err;
1636
1637 ASSERT_RTNL();
1638 err = nlmsg_parse(nlh, sizeof(*ndm), tb, NDA_MAX, NULL);
1639 if (err < 0)
1640 goto out;
1641
1642 err = -EINVAL;
1643 if (tb[NDA_DST] == NULL)
1644 goto out;
1645
1646 ndm = nlmsg_data(nlh);
1647 if (ndm->ndm_ifindex) {
1648 dev = __dev_get_by_index(net, ndm->ndm_ifindex);
1649 if (dev == NULL) {
1650 err = -ENODEV;
1651 goto out;
1652 }
1653
1654 if (tb[NDA_LLADDR] && nla_len(tb[NDA_LLADDR]) < dev->addr_len)
1655 goto out;
1656 }
1657
1658 read_lock(&neigh_tbl_lock);
1659 for (tbl = neigh_tables; tbl; tbl = tbl->next) {
1660 int flags = NEIGH_UPDATE_F_ADMIN | NEIGH_UPDATE_F_OVERRIDE;
1661 struct neighbour *neigh;
1662 void *dst, *lladdr;
1663
1664 if (tbl->family != ndm->ndm_family)
1665 continue;
1666 read_unlock(&neigh_tbl_lock);
1667
1668 if (nla_len(tb[NDA_DST]) < tbl->key_len)
1669 goto out;
1670 dst = nla_data(tb[NDA_DST]);
1671 lladdr = tb[NDA_LLADDR] ? nla_data(tb[NDA_LLADDR]) : NULL;
1672
1673 if (ndm->ndm_flags & NTF_PROXY) {
1674 struct pneigh_entry *pn;
1675
1676 err = -ENOBUFS;
1677 pn = pneigh_lookup(tbl, net, dst, dev, 1);
1678 if (pn) {
1679 pn->flags = ndm->ndm_flags;
1680 err = 0;
1681 }
1682 goto out;
1683 }
1684
1685 if (dev == NULL)
1686 goto out;
1687
1688 neigh = neigh_lookup(tbl, dst, dev);
1689 if (neigh == NULL) {
1690 if (!(nlh->nlmsg_flags & NLM_F_CREATE)) {
1691 err = -ENOENT;
1692 goto out;
1693 }
1694
1695 neigh = __neigh_lookup_errno(tbl, dst, dev);
1696 if (IS_ERR(neigh)) {
1697 err = PTR_ERR(neigh);
1698 goto out;
1699 }
1700 } else {
1701 if (nlh->nlmsg_flags & NLM_F_EXCL) {
1702 err = -EEXIST;
1703 neigh_release(neigh);
1704 goto out;
1705 }
1706
1707 if (!(nlh->nlmsg_flags & NLM_F_REPLACE))
1708 flags &= ~NEIGH_UPDATE_F_OVERRIDE;
1709 }
1710
1711 if (ndm->ndm_flags & NTF_USE) {
1712 neigh_event_send(neigh, NULL);
1713 err = 0;
1714 } else
1715 err = neigh_update(neigh, lladdr, ndm->ndm_state, flags);
1716 neigh_release(neigh);
1717 goto out;
1718 }
1719
1720 read_unlock(&neigh_tbl_lock);
1721 err = -EAFNOSUPPORT;
1722out:
1723 return err;
1724}
1725
1726static int neightbl_fill_parms(struct sk_buff *skb, struct neigh_parms *parms)
1727{
1728 struct nlattr *nest;
1729
1730 nest = nla_nest_start(skb, NDTA_PARMS);
1731 if (nest == NULL)
1732 return -ENOBUFS;
1733
1734 if (parms->dev)
1735 NLA_PUT_U32(skb, NDTPA_IFINDEX, parms->dev->ifindex);
1736
1737 NLA_PUT_U32(skb, NDTPA_REFCNT, atomic_read(&parms->refcnt));
1738 NLA_PUT_U32(skb, NDTPA_QUEUE_LEN, parms->queue_len);
1739 NLA_PUT_U32(skb, NDTPA_PROXY_QLEN, parms->proxy_qlen);
1740 NLA_PUT_U32(skb, NDTPA_APP_PROBES, parms->app_probes);
1741 NLA_PUT_U32(skb, NDTPA_UCAST_PROBES, parms->ucast_probes);
1742 NLA_PUT_U32(skb, NDTPA_MCAST_PROBES, parms->mcast_probes);
1743 NLA_PUT_MSECS(skb, NDTPA_REACHABLE_TIME, parms->reachable_time);
1744 NLA_PUT_MSECS(skb, NDTPA_BASE_REACHABLE_TIME,
1745 parms->base_reachable_time);
1746 NLA_PUT_MSECS(skb, NDTPA_GC_STALETIME, parms->gc_staletime);
1747 NLA_PUT_MSECS(skb, NDTPA_DELAY_PROBE_TIME, parms->delay_probe_time);
1748 NLA_PUT_MSECS(skb, NDTPA_RETRANS_TIME, parms->retrans_time);
1749 NLA_PUT_MSECS(skb, NDTPA_ANYCAST_DELAY, parms->anycast_delay);
1750 NLA_PUT_MSECS(skb, NDTPA_PROXY_DELAY, parms->proxy_delay);
1751 NLA_PUT_MSECS(skb, NDTPA_LOCKTIME, parms->locktime);
1752
1753 return nla_nest_end(skb, nest);
1754
1755nla_put_failure:
1756 nla_nest_cancel(skb, nest);
1757 return -EMSGSIZE;
1758}
1759
1760static int neightbl_fill_info(struct sk_buff *skb, struct neigh_table *tbl,
1761 u32 pid, u32 seq, int type, int flags)
1762{
1763 struct nlmsghdr *nlh;
1764 struct ndtmsg *ndtmsg;
1765
1766 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndtmsg), flags);
1767 if (nlh == NULL)
1768 return -EMSGSIZE;
1769
1770 ndtmsg = nlmsg_data(nlh);
1771
1772 read_lock_bh(&tbl->lock);
1773 ndtmsg->ndtm_family = tbl->family;
1774 ndtmsg->ndtm_pad1 = 0;
1775 ndtmsg->ndtm_pad2 = 0;
1776
1777 NLA_PUT_STRING(skb, NDTA_NAME, tbl->id);
1778 NLA_PUT_MSECS(skb, NDTA_GC_INTERVAL, tbl->gc_interval);
1779 NLA_PUT_U32(skb, NDTA_THRESH1, tbl->gc_thresh1);
1780 NLA_PUT_U32(skb, NDTA_THRESH2, tbl->gc_thresh2);
1781 NLA_PUT_U32(skb, NDTA_THRESH3, tbl->gc_thresh3);
1782
1783 {
1784 unsigned long now = jiffies;
1785 unsigned int flush_delta = now - tbl->last_flush;
1786 unsigned int rand_delta = now - tbl->last_rand;
1787 struct neigh_hash_table *nht;
1788 struct ndt_config ndc = {
1789 .ndtc_key_len = tbl->key_len,
1790 .ndtc_entry_size = tbl->entry_size,
1791 .ndtc_entries = atomic_read(&tbl->entries),
1792 .ndtc_last_flush = jiffies_to_msecs(flush_delta),
1793 .ndtc_last_rand = jiffies_to_msecs(rand_delta),
1794 .ndtc_proxy_qlen = tbl->proxy_queue.qlen,
1795 };
1796
1797 rcu_read_lock_bh();
1798 nht = rcu_dereference_bh(tbl->nht);
1799 ndc.ndtc_hash_rnd = nht->hash_rnd;
1800 ndc.ndtc_hash_mask = ((1 << nht->hash_shift) - 1);
1801 rcu_read_unlock_bh();
1802
1803 NLA_PUT(skb, NDTA_CONFIG, sizeof(ndc), &ndc);
1804 }
1805
1806 {
1807 int cpu;
1808 struct ndt_stats ndst;
1809
1810 memset(&ndst, 0, sizeof(ndst));
1811
1812 for_each_possible_cpu(cpu) {
1813 struct neigh_statistics *st;
1814
1815 st = per_cpu_ptr(tbl->stats, cpu);
1816 ndst.ndts_allocs += st->allocs;
1817 ndst.ndts_destroys += st->destroys;
1818 ndst.ndts_hash_grows += st->hash_grows;
1819 ndst.ndts_res_failed += st->res_failed;
1820 ndst.ndts_lookups += st->lookups;
1821 ndst.ndts_hits += st->hits;
1822 ndst.ndts_rcv_probes_mcast += st->rcv_probes_mcast;
1823 ndst.ndts_rcv_probes_ucast += st->rcv_probes_ucast;
1824 ndst.ndts_periodic_gc_runs += st->periodic_gc_runs;
1825 ndst.ndts_forced_gc_runs += st->forced_gc_runs;
1826 }
1827
1828 NLA_PUT(skb, NDTA_STATS, sizeof(ndst), &ndst);
1829 }
1830
1831 BUG_ON(tbl->parms.dev);
1832 if (neightbl_fill_parms(skb, &tbl->parms) < 0)
1833 goto nla_put_failure;
1834
1835 read_unlock_bh(&tbl->lock);
1836 return nlmsg_end(skb, nlh);
1837
1838nla_put_failure:
1839 read_unlock_bh(&tbl->lock);
1840 nlmsg_cancel(skb, nlh);
1841 return -EMSGSIZE;
1842}
1843
1844static int neightbl_fill_param_info(struct sk_buff *skb,
1845 struct neigh_table *tbl,
1846 struct neigh_parms *parms,
1847 u32 pid, u32 seq, int type,
1848 unsigned int flags)
1849{
1850 struct ndtmsg *ndtmsg;
1851 struct nlmsghdr *nlh;
1852
1853 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndtmsg), flags);
1854 if (nlh == NULL)
1855 return -EMSGSIZE;
1856
1857 ndtmsg = nlmsg_data(nlh);
1858
1859 read_lock_bh(&tbl->lock);
1860 ndtmsg->ndtm_family = tbl->family;
1861 ndtmsg->ndtm_pad1 = 0;
1862 ndtmsg->ndtm_pad2 = 0;
1863
1864 if (nla_put_string(skb, NDTA_NAME, tbl->id) < 0 ||
1865 neightbl_fill_parms(skb, parms) < 0)
1866 goto errout;
1867
1868 read_unlock_bh(&tbl->lock);
1869 return nlmsg_end(skb, nlh);
1870errout:
1871 read_unlock_bh(&tbl->lock);
1872 nlmsg_cancel(skb, nlh);
1873 return -EMSGSIZE;
1874}
1875
1876static const struct nla_policy nl_neightbl_policy[NDTA_MAX+1] = {
1877 [NDTA_NAME] = { .type = NLA_STRING },
1878 [NDTA_THRESH1] = { .type = NLA_U32 },
1879 [NDTA_THRESH2] = { .type = NLA_U32 },
1880 [NDTA_THRESH3] = { .type = NLA_U32 },
1881 [NDTA_GC_INTERVAL] = { .type = NLA_U64 },
1882 [NDTA_PARMS] = { .type = NLA_NESTED },
1883};
1884
1885static const struct nla_policy nl_ntbl_parm_policy[NDTPA_MAX+1] = {
1886 [NDTPA_IFINDEX] = { .type = NLA_U32 },
1887 [NDTPA_QUEUE_LEN] = { .type = NLA_U32 },
1888 [NDTPA_PROXY_QLEN] = { .type = NLA_U32 },
1889 [NDTPA_APP_PROBES] = { .type = NLA_U32 },
1890 [NDTPA_UCAST_PROBES] = { .type = NLA_U32 },
1891 [NDTPA_MCAST_PROBES] = { .type = NLA_U32 },
1892 [NDTPA_BASE_REACHABLE_TIME] = { .type = NLA_U64 },
1893 [NDTPA_GC_STALETIME] = { .type = NLA_U64 },
1894 [NDTPA_DELAY_PROBE_TIME] = { .type = NLA_U64 },
1895 [NDTPA_RETRANS_TIME] = { .type = NLA_U64 },
1896 [NDTPA_ANYCAST_DELAY] = { .type = NLA_U64 },
1897 [NDTPA_PROXY_DELAY] = { .type = NLA_U64 },
1898 [NDTPA_LOCKTIME] = { .type = NLA_U64 },
1899};
1900
1901static int neightbl_set(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
1902{
1903 struct net *net = sock_net(skb->sk);
1904 struct neigh_table *tbl;
1905 struct ndtmsg *ndtmsg;
1906 struct nlattr *tb[NDTA_MAX+1];
1907 int err;
1908
1909 err = nlmsg_parse(nlh, sizeof(*ndtmsg), tb, NDTA_MAX,
1910 nl_neightbl_policy);
1911 if (err < 0)
1912 goto errout;
1913
1914 if (tb[NDTA_NAME] == NULL) {
1915 err = -EINVAL;
1916 goto errout;
1917 }
1918
1919 ndtmsg = nlmsg_data(nlh);
1920 read_lock(&neigh_tbl_lock);
1921 for (tbl = neigh_tables; tbl; tbl = tbl->next) {
1922 if (ndtmsg->ndtm_family && tbl->family != ndtmsg->ndtm_family)
1923 continue;
1924
1925 if (nla_strcmp(tb[NDTA_NAME], tbl->id) == 0)
1926 break;
1927 }
1928
1929 if (tbl == NULL) {
1930 err = -ENOENT;
1931 goto errout_locked;
1932 }
1933
1934 /*
1935 * We acquire tbl->lock to be nice to the periodic timers and
1936 * make sure they always see a consistent set of values.
1937 */
1938 write_lock_bh(&tbl->lock);
1939
1940 if (tb[NDTA_PARMS]) {
1941 struct nlattr *tbp[NDTPA_MAX+1];
1942 struct neigh_parms *p;
1943 int i, ifindex = 0;
1944
1945 err = nla_parse_nested(tbp, NDTPA_MAX, tb[NDTA_PARMS],
1946 nl_ntbl_parm_policy);
1947 if (err < 0)
1948 goto errout_tbl_lock;
1949
1950 if (tbp[NDTPA_IFINDEX])
1951 ifindex = nla_get_u32(tbp[NDTPA_IFINDEX]);
1952
1953 p = lookup_neigh_parms(tbl, net, ifindex);
1954 if (p == NULL) {
1955 err = -ENOENT;
1956 goto errout_tbl_lock;
1957 }
1958
1959 for (i = 1; i <= NDTPA_MAX; i++) {
1960 if (tbp[i] == NULL)
1961 continue;
1962
1963 switch (i) {
1964 case NDTPA_QUEUE_LEN:
1965 p->queue_len = nla_get_u32(tbp[i]);
1966 break;
1967 case NDTPA_PROXY_QLEN:
1968 p->proxy_qlen = nla_get_u32(tbp[i]);
1969 break;
1970 case NDTPA_APP_PROBES:
1971 p->app_probes = nla_get_u32(tbp[i]);
1972 break;
1973 case NDTPA_UCAST_PROBES:
1974 p->ucast_probes = nla_get_u32(tbp[i]);
1975 break;
1976 case NDTPA_MCAST_PROBES:
1977 p->mcast_probes = nla_get_u32(tbp[i]);
1978 break;
1979 case NDTPA_BASE_REACHABLE_TIME:
1980 p->base_reachable_time = nla_get_msecs(tbp[i]);
1981 break;
1982 case NDTPA_GC_STALETIME:
1983 p->gc_staletime = nla_get_msecs(tbp[i]);
1984 break;
1985 case NDTPA_DELAY_PROBE_TIME:
1986 p->delay_probe_time = nla_get_msecs(tbp[i]);
1987 break;
1988 case NDTPA_RETRANS_TIME:
1989 p->retrans_time = nla_get_msecs(tbp[i]);
1990 break;
1991 case NDTPA_ANYCAST_DELAY:
1992 p->anycast_delay = nla_get_msecs(tbp[i]);
1993 break;
1994 case NDTPA_PROXY_DELAY:
1995 p->proxy_delay = nla_get_msecs(tbp[i]);
1996 break;
1997 case NDTPA_LOCKTIME:
1998 p->locktime = nla_get_msecs(tbp[i]);
1999 break;
2000 }
2001 }
2002 }
2003
2004 if (tb[NDTA_THRESH1])
2005 tbl->gc_thresh1 = nla_get_u32(tb[NDTA_THRESH1]);
2006
2007 if (tb[NDTA_THRESH2])
2008 tbl->gc_thresh2 = nla_get_u32(tb[NDTA_THRESH2]);
2009
2010 if (tb[NDTA_THRESH3])
2011 tbl->gc_thresh3 = nla_get_u32(tb[NDTA_THRESH3]);
2012
2013 if (tb[NDTA_GC_INTERVAL])
2014 tbl->gc_interval = nla_get_msecs(tb[NDTA_GC_INTERVAL]);
2015
2016 err = 0;
2017
2018errout_tbl_lock:
2019 write_unlock_bh(&tbl->lock);
2020errout_locked:
2021 read_unlock(&neigh_tbl_lock);
2022errout:
2023 return err;
2024}
2025
2026static int neightbl_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
2027{
2028 struct net *net = sock_net(skb->sk);
2029 int family, tidx, nidx = 0;
2030 int tbl_skip = cb->args[0];
2031 int neigh_skip = cb->args[1];
2032 struct neigh_table *tbl;
2033
2034 family = ((struct rtgenmsg *) nlmsg_data(cb->nlh))->rtgen_family;
2035
2036 read_lock(&neigh_tbl_lock);
2037 for (tbl = neigh_tables, tidx = 0; tbl; tbl = tbl->next, tidx++) {
2038 struct neigh_parms *p;
2039
2040 if (tidx < tbl_skip || (family && tbl->family != family))
2041 continue;
2042
2043 if (neightbl_fill_info(skb, tbl, NETLINK_CB(cb->skb).pid,
2044 cb->nlh->nlmsg_seq, RTM_NEWNEIGHTBL,
2045 NLM_F_MULTI) <= 0)
2046 break;
2047
2048 for (nidx = 0, p = tbl->parms.next; p; p = p->next) {
2049 if (!net_eq(neigh_parms_net(p), net))
2050 continue;
2051
2052 if (nidx < neigh_skip)
2053 goto next;
2054
2055 if (neightbl_fill_param_info(skb, tbl, p,
2056 NETLINK_CB(cb->skb).pid,
2057 cb->nlh->nlmsg_seq,
2058 RTM_NEWNEIGHTBL,
2059 NLM_F_MULTI) <= 0)
2060 goto out;
2061 next:
2062 nidx++;
2063 }
2064
2065 neigh_skip = 0;
2066 }
2067out:
2068 read_unlock(&neigh_tbl_lock);
2069 cb->args[0] = tidx;
2070 cb->args[1] = nidx;
2071
2072 return skb->len;
2073}
2074
2075static int neigh_fill_info(struct sk_buff *skb, struct neighbour *neigh,
2076 u32 pid, u32 seq, int type, unsigned int flags)
2077{
2078 unsigned long now = jiffies;
2079 struct nda_cacheinfo ci;
2080 struct nlmsghdr *nlh;
2081 struct ndmsg *ndm;
2082
2083 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndm), flags);
2084 if (nlh == NULL)
2085 return -EMSGSIZE;
2086
2087 ndm = nlmsg_data(nlh);
2088 ndm->ndm_family = neigh->ops->family;
2089 ndm->ndm_pad1 = 0;
2090 ndm->ndm_pad2 = 0;
2091 ndm->ndm_flags = neigh->flags;
2092 ndm->ndm_type = neigh->type;
2093 ndm->ndm_ifindex = neigh->dev->ifindex;
2094
2095 NLA_PUT(skb, NDA_DST, neigh->tbl->key_len, neigh->primary_key);
2096
2097 read_lock_bh(&neigh->lock);
2098 ndm->ndm_state = neigh->nud_state;
2099 if (neigh->nud_state & NUD_VALID) {
2100 char haddr[MAX_ADDR_LEN];
2101
2102 neigh_ha_snapshot(haddr, neigh, neigh->dev);
2103 if (nla_put(skb, NDA_LLADDR, neigh->dev->addr_len, haddr) < 0) {
2104 read_unlock_bh(&neigh->lock);
2105 goto nla_put_failure;
2106 }
2107 }
2108
2109 ci.ndm_used = jiffies_to_clock_t(now - neigh->used);
2110 ci.ndm_confirmed = jiffies_to_clock_t(now - neigh->confirmed);
2111 ci.ndm_updated = jiffies_to_clock_t(now - neigh->updated);
2112 ci.ndm_refcnt = atomic_read(&neigh->refcnt) - 1;
2113 read_unlock_bh(&neigh->lock);
2114
2115 NLA_PUT_U32(skb, NDA_PROBES, atomic_read(&neigh->probes));
2116 NLA_PUT(skb, NDA_CACHEINFO, sizeof(ci), &ci);
2117
2118 return nlmsg_end(skb, nlh);
2119
2120nla_put_failure:
2121 nlmsg_cancel(skb, nlh);
2122 return -EMSGSIZE;
2123}
2124
2125static void neigh_update_notify(struct neighbour *neigh)
2126{
2127 call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, neigh);
2128 __neigh_notify(neigh, RTM_NEWNEIGH, 0);
2129}
2130
2131static int neigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb,
2132 struct netlink_callback *cb)
2133{
2134 struct net *net = sock_net(skb->sk);
2135 struct neighbour *n;
2136 int rc, h, s_h = cb->args[1];
2137 int idx, s_idx = idx = cb->args[2];
2138 struct neigh_hash_table *nht;
2139
2140 rcu_read_lock_bh();
2141 nht = rcu_dereference_bh(tbl->nht);
2142
2143 for (h = 0; h < (1 << nht->hash_shift); h++) {
2144 if (h < s_h)
2145 continue;
2146 if (h > s_h)
2147 s_idx = 0;
2148 for (n = rcu_dereference_bh(nht->hash_buckets[h]), idx = 0;
2149 n != NULL;
2150 n = rcu_dereference_bh(n->next)) {
2151 if (!net_eq(dev_net(n->dev), net))
2152 continue;
2153 if (idx < s_idx)
2154 goto next;
2155 if (neigh_fill_info(skb, n, NETLINK_CB(cb->skb).pid,
2156 cb->nlh->nlmsg_seq,
2157 RTM_NEWNEIGH,
2158 NLM_F_MULTI) <= 0) {
2159 rc = -1;
2160 goto out;
2161 }
2162next:
2163 idx++;
2164 }
2165 }
2166 rc = skb->len;
2167out:
2168 rcu_read_unlock_bh();
2169 cb->args[1] = h;
2170 cb->args[2] = idx;
2171 return rc;
2172}
2173
2174static int neigh_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
2175{
2176 struct neigh_table *tbl;
2177 int t, family, s_t;
2178
2179 read_lock(&neigh_tbl_lock);
2180 family = ((struct rtgenmsg *) nlmsg_data(cb->nlh))->rtgen_family;
2181 s_t = cb->args[0];
2182
2183 for (tbl = neigh_tables, t = 0; tbl; tbl = tbl->next, t++) {
2184 if (t < s_t || (family && tbl->family != family))
2185 continue;
2186 if (t > s_t)
2187 memset(&cb->args[1], 0, sizeof(cb->args) -
2188 sizeof(cb->args[0]));
2189 if (neigh_dump_table(tbl, skb, cb) < 0)
2190 break;
2191 }
2192 read_unlock(&neigh_tbl_lock);
2193
2194 cb->args[0] = t;
2195 return skb->len;
2196}
2197
2198void neigh_for_each(struct neigh_table *tbl, void (*cb)(struct neighbour *, void *), void *cookie)
2199{
2200 int chain;
2201 struct neigh_hash_table *nht;
2202
2203 rcu_read_lock_bh();
2204 nht = rcu_dereference_bh(tbl->nht);
2205
2206 read_lock(&tbl->lock); /* avoid resizes */
2207 for (chain = 0; chain < (1 << nht->hash_shift); chain++) {
2208 struct neighbour *n;
2209
2210 for (n = rcu_dereference_bh(nht->hash_buckets[chain]);
2211 n != NULL;
2212 n = rcu_dereference_bh(n->next))
2213 cb(n, cookie);
2214 }
2215 read_unlock(&tbl->lock);
2216 rcu_read_unlock_bh();
2217}
2218EXPORT_SYMBOL(neigh_for_each);
2219
2220/* The tbl->lock must be held as a writer and BH disabled. */
2221void __neigh_for_each_release(struct neigh_table *tbl,
2222 int (*cb)(struct neighbour *))
2223{
2224 int chain;
2225 struct neigh_hash_table *nht;
2226
2227 nht = rcu_dereference_protected(tbl->nht,
2228 lockdep_is_held(&tbl->lock));
2229 for (chain = 0; chain < (1 << nht->hash_shift); chain++) {
2230 struct neighbour *n;
2231 struct neighbour __rcu **np;
2232
2233 np = &nht->hash_buckets[chain];
2234 while ((n = rcu_dereference_protected(*np,
2235 lockdep_is_held(&tbl->lock))) != NULL) {
2236 int release;
2237
2238 write_lock(&n->lock);
2239 release = cb(n);
2240 if (release) {
2241 rcu_assign_pointer(*np,
2242 rcu_dereference_protected(n->next,
2243 lockdep_is_held(&tbl->lock)));
2244 n->dead = 1;
2245 } else
2246 np = &n->next;
2247 write_unlock(&n->lock);
2248 if (release)
2249 neigh_cleanup_and_release(n);
2250 }
2251 }
2252}
2253EXPORT_SYMBOL(__neigh_for_each_release);
2254
2255#ifdef CONFIG_PROC_FS
2256
2257static struct neighbour *neigh_get_first(struct seq_file *seq)
2258{
2259 struct neigh_seq_state *state = seq->private;
2260 struct net *net = seq_file_net(seq);
2261 struct neigh_hash_table *nht = state->nht;
2262 struct neighbour *n = NULL;
2263 int bucket = state->bucket;
2264
2265 state->flags &= ~NEIGH_SEQ_IS_PNEIGH;
2266 for (bucket = 0; bucket < (1 << nht->hash_shift); bucket++) {
2267 n = rcu_dereference_bh(nht->hash_buckets[bucket]);
2268
2269 while (n) {
2270 if (!net_eq(dev_net(n->dev), net))
2271 goto next;
2272 if (state->neigh_sub_iter) {
2273 loff_t fakep = 0;
2274 void *v;
2275
2276 v = state->neigh_sub_iter(state, n, &fakep);
2277 if (!v)
2278 goto next;
2279 }
2280 if (!(state->flags & NEIGH_SEQ_SKIP_NOARP))
2281 break;
2282 if (n->nud_state & ~NUD_NOARP)
2283 break;
2284next:
2285 n = rcu_dereference_bh(n->next);
2286 }
2287
2288 if (n)
2289 break;
2290 }
2291 state->bucket = bucket;
2292
2293 return n;
2294}
2295
2296static struct neighbour *neigh_get_next(struct seq_file *seq,
2297 struct neighbour *n,
2298 loff_t *pos)
2299{
2300 struct neigh_seq_state *state = seq->private;
2301 struct net *net = seq_file_net(seq);
2302 struct neigh_hash_table *nht = state->nht;
2303
2304 if (state->neigh_sub_iter) {
2305 void *v = state->neigh_sub_iter(state, n, pos);
2306 if (v)
2307 return n;
2308 }
2309 n = rcu_dereference_bh(n->next);
2310
2311 while (1) {
2312 while (n) {
2313 if (!net_eq(dev_net(n->dev), net))
2314 goto next;
2315 if (state->neigh_sub_iter) {
2316 void *v = state->neigh_sub_iter(state, n, pos);
2317 if (v)
2318 return n;
2319 goto next;
2320 }
2321 if (!(state->flags & NEIGH_SEQ_SKIP_NOARP))
2322 break;
2323
2324 if (n->nud_state & ~NUD_NOARP)
2325 break;
2326next:
2327 n = rcu_dereference_bh(n->next);
2328 }
2329
2330 if (n)
2331 break;
2332
2333 if (++state->bucket >= (1 << nht->hash_shift))
2334 break;
2335
2336 n = rcu_dereference_bh(nht->hash_buckets[state->bucket]);
2337 }
2338
2339 if (n && pos)
2340 --(*pos);
2341 return n;
2342}
2343
2344static struct neighbour *neigh_get_idx(struct seq_file *seq, loff_t *pos)
2345{
2346 struct neighbour *n = neigh_get_first(seq);
2347
2348 if (n) {
2349 --(*pos);
2350 while (*pos) {
2351 n = neigh_get_next(seq, n, pos);
2352 if (!n)
2353 break;
2354 }
2355 }
2356 return *pos ? NULL : n;
2357}
2358
2359static struct pneigh_entry *pneigh_get_first(struct seq_file *seq)
2360{
2361 struct neigh_seq_state *state = seq->private;
2362 struct net *net = seq_file_net(seq);
2363 struct neigh_table *tbl = state->tbl;
2364 struct pneigh_entry *pn = NULL;
2365 int bucket = state->bucket;
2366
2367 state->flags |= NEIGH_SEQ_IS_PNEIGH;
2368 for (bucket = 0; bucket <= PNEIGH_HASHMASK; bucket++) {
2369 pn = tbl->phash_buckets[bucket];
2370 while (pn && !net_eq(pneigh_net(pn), net))
2371 pn = pn->next;
2372 if (pn)
2373 break;
2374 }
2375 state->bucket = bucket;
2376
2377 return pn;
2378}
2379
2380static struct pneigh_entry *pneigh_get_next(struct seq_file *seq,
2381 struct pneigh_entry *pn,
2382 loff_t *pos)
2383{
2384 struct neigh_seq_state *state = seq->private;
2385 struct net *net = seq_file_net(seq);
2386 struct neigh_table *tbl = state->tbl;
2387
2388 pn = pn->next;
2389 while (!pn) {
2390 if (++state->bucket > PNEIGH_HASHMASK)
2391 break;
2392 pn = tbl->phash_buckets[state->bucket];
2393 while (pn && !net_eq(pneigh_net(pn), net))
2394 pn = pn->next;
2395 if (pn)
2396 break;
2397 }
2398
2399 if (pn && pos)
2400 --(*pos);
2401
2402 return pn;
2403}
2404
2405static struct pneigh_entry *pneigh_get_idx(struct seq_file *seq, loff_t *pos)
2406{
2407 struct pneigh_entry *pn = pneigh_get_first(seq);
2408
2409 if (pn) {
2410 --(*pos);
2411 while (*pos) {
2412 pn = pneigh_get_next(seq, pn, pos);
2413 if (!pn)
2414 break;
2415 }
2416 }
2417 return *pos ? NULL : pn;
2418}
2419
2420static void *neigh_get_idx_any(struct seq_file *seq, loff_t *pos)
2421{
2422 struct neigh_seq_state *state = seq->private;
2423 void *rc;
2424 loff_t idxpos = *pos;
2425
2426 rc = neigh_get_idx(seq, &idxpos);
2427 if (!rc && !(state->flags & NEIGH_SEQ_NEIGH_ONLY))
2428 rc = pneigh_get_idx(seq, &idxpos);
2429
2430 return rc;
2431}
2432
2433void *neigh_seq_start(struct seq_file *seq, loff_t *pos, struct neigh_table *tbl, unsigned int neigh_seq_flags)
2434 __acquires(rcu_bh)
2435{
2436 struct neigh_seq_state *state = seq->private;
2437
2438 state->tbl = tbl;
2439 state->bucket = 0;
2440 state->flags = (neigh_seq_flags & ~NEIGH_SEQ_IS_PNEIGH);
2441
2442 rcu_read_lock_bh();
2443 state->nht = rcu_dereference_bh(tbl->nht);
2444
2445 return *pos ? neigh_get_idx_any(seq, pos) : SEQ_START_TOKEN;
2446}
2447EXPORT_SYMBOL(neigh_seq_start);
2448
2449void *neigh_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2450{
2451 struct neigh_seq_state *state;
2452 void *rc;
2453
2454 if (v == SEQ_START_TOKEN) {
2455 rc = neigh_get_first(seq);
2456 goto out;
2457 }
2458
2459 state = seq->private;
2460 if (!(state->flags & NEIGH_SEQ_IS_PNEIGH)) {
2461 rc = neigh_get_next(seq, v, NULL);
2462 if (rc)
2463 goto out;
2464 if (!(state->flags & NEIGH_SEQ_NEIGH_ONLY))
2465 rc = pneigh_get_first(seq);
2466 } else {
2467 BUG_ON(state->flags & NEIGH_SEQ_NEIGH_ONLY);
2468 rc = pneigh_get_next(seq, v, NULL);
2469 }
2470out:
2471 ++(*pos);
2472 return rc;
2473}
2474EXPORT_SYMBOL(neigh_seq_next);
2475
2476void neigh_seq_stop(struct seq_file *seq, void *v)
2477 __releases(rcu_bh)
2478{
2479 rcu_read_unlock_bh();
2480}
2481EXPORT_SYMBOL(neigh_seq_stop);
2482
2483/* statistics via seq_file */
2484
2485static void *neigh_stat_seq_start(struct seq_file *seq, loff_t *pos)
2486{
2487 struct neigh_table *tbl = seq->private;
2488 int cpu;
2489
2490 if (*pos == 0)
2491 return SEQ_START_TOKEN;
2492
2493 for (cpu = *pos-1; cpu < nr_cpu_ids; ++cpu) {
2494 if (!cpu_possible(cpu))
2495 continue;
2496 *pos = cpu+1;
2497 return per_cpu_ptr(tbl->stats, cpu);
2498 }
2499 return NULL;
2500}
2501
2502static void *neigh_stat_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2503{
2504 struct neigh_table *tbl = seq->private;
2505 int cpu;
2506
2507 for (cpu = *pos; cpu < nr_cpu_ids; ++cpu) {
2508 if (!cpu_possible(cpu))
2509 continue;
2510 *pos = cpu+1;
2511 return per_cpu_ptr(tbl->stats, cpu);
2512 }
2513 return NULL;
2514}
2515
2516static void neigh_stat_seq_stop(struct seq_file *seq, void *v)
2517{
2518
2519}
2520
2521static int neigh_stat_seq_show(struct seq_file *seq, void *v)
2522{
2523 struct neigh_table *tbl = seq->private;
2524 struct neigh_statistics *st = v;
2525
2526 if (v == SEQ_START_TOKEN) {
2527 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");
2528 return 0;
2529 }
2530
2531 seq_printf(seq, "%08x %08lx %08lx %08lx %08lx %08lx %08lx "
2532 "%08lx %08lx %08lx %08lx %08lx\n",
2533 atomic_read(&tbl->entries),
2534
2535 st->allocs,
2536 st->destroys,
2537 st->hash_grows,
2538
2539 st->lookups,
2540 st->hits,
2541
2542 st->res_failed,
2543
2544 st->rcv_probes_mcast,
2545 st->rcv_probes_ucast,
2546
2547 st->periodic_gc_runs,
2548 st->forced_gc_runs,
2549 st->unres_discards
2550 );
2551
2552 return 0;
2553}
2554
2555static const struct seq_operations neigh_stat_seq_ops = {
2556 .start = neigh_stat_seq_start,
2557 .next = neigh_stat_seq_next,
2558 .stop = neigh_stat_seq_stop,
2559 .show = neigh_stat_seq_show,
2560};
2561
2562static int neigh_stat_seq_open(struct inode *inode, struct file *file)
2563{
2564 int ret = seq_open(file, &neigh_stat_seq_ops);
2565
2566 if (!ret) {
2567 struct seq_file *sf = file->private_data;
2568 sf->private = PDE(inode)->data;
2569 }
2570 return ret;
2571};
2572
2573static const struct file_operations neigh_stat_seq_fops = {
2574 .owner = THIS_MODULE,
2575 .open = neigh_stat_seq_open,
2576 .read = seq_read,
2577 .llseek = seq_lseek,
2578 .release = seq_release,
2579};
2580
2581#endif /* CONFIG_PROC_FS */
2582
2583static inline size_t neigh_nlmsg_size(void)
2584{
2585 return NLMSG_ALIGN(sizeof(struct ndmsg))
2586 + nla_total_size(MAX_ADDR_LEN) /* NDA_DST */
2587 + nla_total_size(MAX_ADDR_LEN) /* NDA_LLADDR */
2588 + nla_total_size(sizeof(struct nda_cacheinfo))
2589 + nla_total_size(4); /* NDA_PROBES */
2590}
2591
2592static void __neigh_notify(struct neighbour *n, int type, int flags)
2593{
2594 struct net *net = dev_net(n->dev);
2595 struct sk_buff *skb;
2596 int err = -ENOBUFS;
2597
2598 skb = nlmsg_new(neigh_nlmsg_size(), GFP_ATOMIC);
2599 if (skb == NULL)
2600 goto errout;
2601
2602 err = neigh_fill_info(skb, n, 0, 0, type, flags);
2603 if (err < 0) {
2604 /* -EMSGSIZE implies BUG in neigh_nlmsg_size() */
2605 WARN_ON(err == -EMSGSIZE);
2606 kfree_skb(skb);
2607 goto errout;
2608 }
2609 rtnl_notify(skb, net, 0, RTNLGRP_NEIGH, NULL, GFP_ATOMIC);
2610 return;
2611errout:
2612 if (err < 0)
2613 rtnl_set_sk_err(net, RTNLGRP_NEIGH, err);
2614}
2615
2616#ifdef CONFIG_ARPD
2617void neigh_app_ns(struct neighbour *n)
2618{
2619 __neigh_notify(n, RTM_GETNEIGH, NLM_F_REQUEST);
2620}
2621EXPORT_SYMBOL(neigh_app_ns);
2622#endif /* CONFIG_ARPD */
2623
2624#ifdef CONFIG_SYSCTL
2625
2626#define NEIGH_VARS_MAX 19
2627
2628static struct neigh_sysctl_table {
2629 struct ctl_table_header *sysctl_header;
2630 struct ctl_table neigh_vars[NEIGH_VARS_MAX];
2631 char *dev_name;
2632} neigh_sysctl_template __read_mostly = {
2633 .neigh_vars = {
2634 {
2635 .procname = "mcast_solicit",
2636 .maxlen = sizeof(int),
2637 .mode = 0644,
2638 .proc_handler = proc_dointvec,
2639 },
2640 {
2641 .procname = "ucast_solicit",
2642 .maxlen = sizeof(int),
2643 .mode = 0644,
2644 .proc_handler = proc_dointvec,
2645 },
2646 {
2647 .procname = "app_solicit",
2648 .maxlen = sizeof(int),
2649 .mode = 0644,
2650 .proc_handler = proc_dointvec,
2651 },
2652 {
2653 .procname = "retrans_time",
2654 .maxlen = sizeof(int),
2655 .mode = 0644,
2656 .proc_handler = proc_dointvec_userhz_jiffies,
2657 },
2658 {
2659 .procname = "base_reachable_time",
2660 .maxlen = sizeof(int),
2661 .mode = 0644,
2662 .proc_handler = proc_dointvec_jiffies,
2663 },
2664 {
2665 .procname = "delay_first_probe_time",
2666 .maxlen = sizeof(int),
2667 .mode = 0644,
2668 .proc_handler = proc_dointvec_jiffies,
2669 },
2670 {
2671 .procname = "gc_stale_time",
2672 .maxlen = sizeof(int),
2673 .mode = 0644,
2674 .proc_handler = proc_dointvec_jiffies,
2675 },
2676 {
2677 .procname = "unres_qlen",
2678 .maxlen = sizeof(int),
2679 .mode = 0644,
2680 .proc_handler = proc_dointvec,
2681 },
2682 {
2683 .procname = "proxy_qlen",
2684 .maxlen = sizeof(int),
2685 .mode = 0644,
2686 .proc_handler = proc_dointvec,
2687 },
2688 {
2689 .procname = "anycast_delay",
2690 .maxlen = sizeof(int),
2691 .mode = 0644,
2692 .proc_handler = proc_dointvec_userhz_jiffies,
2693 },
2694 {
2695 .procname = "proxy_delay",
2696 .maxlen = sizeof(int),
2697 .mode = 0644,
2698 .proc_handler = proc_dointvec_userhz_jiffies,
2699 },
2700 {
2701 .procname = "locktime",
2702 .maxlen = sizeof(int),
2703 .mode = 0644,
2704 .proc_handler = proc_dointvec_userhz_jiffies,
2705 },
2706 {
2707 .procname = "retrans_time_ms",
2708 .maxlen = sizeof(int),
2709 .mode = 0644,
2710 .proc_handler = proc_dointvec_ms_jiffies,
2711 },
2712 {
2713 .procname = "base_reachable_time_ms",
2714 .maxlen = sizeof(int),
2715 .mode = 0644,
2716 .proc_handler = proc_dointvec_ms_jiffies,
2717 },
2718 {
2719 .procname = "gc_interval",
2720 .maxlen = sizeof(int),
2721 .mode = 0644,
2722 .proc_handler = proc_dointvec_jiffies,
2723 },
2724 {
2725 .procname = "gc_thresh1",
2726 .maxlen = sizeof(int),
2727 .mode = 0644,
2728 .proc_handler = proc_dointvec,
2729 },
2730 {
2731 .procname = "gc_thresh2",
2732 .maxlen = sizeof(int),
2733 .mode = 0644,
2734 .proc_handler = proc_dointvec,
2735 },
2736 {
2737 .procname = "gc_thresh3",
2738 .maxlen = sizeof(int),
2739 .mode = 0644,
2740 .proc_handler = proc_dointvec,
2741 },
2742 {},
2743 },
2744};
2745
2746int neigh_sysctl_register(struct net_device *dev, struct neigh_parms *p,
2747 char *p_name, proc_handler *handler)
2748{
2749 struct neigh_sysctl_table *t;
2750 const char *dev_name_source = NULL;
2751
2752#define NEIGH_CTL_PATH_ROOT 0
2753#define NEIGH_CTL_PATH_PROTO 1
2754#define NEIGH_CTL_PATH_NEIGH 2
2755#define NEIGH_CTL_PATH_DEV 3
2756
2757 struct ctl_path neigh_path[] = {
2758 { .procname = "net", },
2759 { .procname = "proto", },
2760 { .procname = "neigh", },
2761 { .procname = "default", },
2762 { },
2763 };
2764
2765 t = kmemdup(&neigh_sysctl_template, sizeof(*t), GFP_KERNEL);
2766 if (!t)
2767 goto err;
2768
2769 t->neigh_vars[0].data = &p->mcast_probes;
2770 t->neigh_vars[1].data = &p->ucast_probes;
2771 t->neigh_vars[2].data = &p->app_probes;
2772 t->neigh_vars[3].data = &p->retrans_time;
2773 t->neigh_vars[4].data = &p->base_reachable_time;
2774 t->neigh_vars[5].data = &p->delay_probe_time;
2775 t->neigh_vars[6].data = &p->gc_staletime;
2776 t->neigh_vars[7].data = &p->queue_len;
2777 t->neigh_vars[8].data = &p->proxy_qlen;
2778 t->neigh_vars[9].data = &p->anycast_delay;
2779 t->neigh_vars[10].data = &p->proxy_delay;
2780 t->neigh_vars[11].data = &p->locktime;
2781 t->neigh_vars[12].data = &p->retrans_time;
2782 t->neigh_vars[13].data = &p->base_reachable_time;
2783
2784 if (dev) {
2785 dev_name_source = dev->name;
2786 /* Terminate the table early */
2787 memset(&t->neigh_vars[14], 0, sizeof(t->neigh_vars[14]));
2788 } else {
2789 dev_name_source = neigh_path[NEIGH_CTL_PATH_DEV].procname;
2790 t->neigh_vars[14].data = (int *)(p + 1);
2791 t->neigh_vars[15].data = (int *)(p + 1) + 1;
2792 t->neigh_vars[16].data = (int *)(p + 1) + 2;
2793 t->neigh_vars[17].data = (int *)(p + 1) + 3;
2794 }
2795
2796
2797 if (handler) {
2798 /* RetransTime */
2799 t->neigh_vars[3].proc_handler = handler;
2800 t->neigh_vars[3].extra1 = dev;
2801 /* ReachableTime */
2802 t->neigh_vars[4].proc_handler = handler;
2803 t->neigh_vars[4].extra1 = dev;
2804 /* RetransTime (in milliseconds)*/
2805 t->neigh_vars[12].proc_handler = handler;
2806 t->neigh_vars[12].extra1 = dev;
2807 /* ReachableTime (in milliseconds) */
2808 t->neigh_vars[13].proc_handler = handler;
2809 t->neigh_vars[13].extra1 = dev;
2810 }
2811
2812 t->dev_name = kstrdup(dev_name_source, GFP_KERNEL);
2813 if (!t->dev_name)
2814 goto free;
2815
2816 neigh_path[NEIGH_CTL_PATH_DEV].procname = t->dev_name;
2817 neigh_path[NEIGH_CTL_PATH_PROTO].procname = p_name;
2818
2819 t->sysctl_header =
2820 register_net_sysctl_table(neigh_parms_net(p), neigh_path, t->neigh_vars);
2821 if (!t->sysctl_header)
2822 goto free_procname;
2823
2824 p->sysctl_table = t;
2825 return 0;
2826
2827free_procname:
2828 kfree(t->dev_name);
2829free:
2830 kfree(t);
2831err:
2832 return -ENOBUFS;
2833}
2834EXPORT_SYMBOL(neigh_sysctl_register);
2835
2836void neigh_sysctl_unregister(struct neigh_parms *p)
2837{
2838 if (p->sysctl_table) {
2839 struct neigh_sysctl_table *t = p->sysctl_table;
2840 p->sysctl_table = NULL;
2841 unregister_sysctl_table(t->sysctl_header);
2842 kfree(t->dev_name);
2843 kfree(t);
2844 }
2845}
2846EXPORT_SYMBOL(neigh_sysctl_unregister);
2847
2848#endif /* CONFIG_SYSCTL */
2849
2850static int __init neigh_init(void)
2851{
2852 rtnl_register(PF_UNSPEC, RTM_NEWNEIGH, neigh_add, NULL, NULL);
2853 rtnl_register(PF_UNSPEC, RTM_DELNEIGH, neigh_delete, NULL, NULL);
2854 rtnl_register(PF_UNSPEC, RTM_GETNEIGH, NULL, neigh_dump_info, NULL);
2855
2856 rtnl_register(PF_UNSPEC, RTM_GETNEIGHTBL, NULL, neightbl_dump_info,
2857 NULL);
2858 rtnl_register(PF_UNSPEC, RTM_SETNEIGHTBL, neightbl_set, NULL, NULL);
2859
2860 return 0;
2861}
2862
2863subsys_initcall(neigh_init);
2864
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 ? (prandom_u32() % 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}
126
127static void neigh_update_gc_list(struct neighbour *n)
128{
129 bool on_gc_list, exempt_from_gc;
130
131 write_lock_bh(&n->tbl->lock);
132 write_lock(&n->lock);
133
134 if (n->dead)
135 goto out;
136
137 /* remove from the gc list if new state is permanent or if neighbor
138 * is externally learned; otherwise entry should be on the gc list
139 */
140 exempt_from_gc = n->nud_state & NUD_PERMANENT ||
141 n->flags & NTF_EXT_LEARNED;
142 on_gc_list = !list_empty(&n->gc_list);
143
144 if (exempt_from_gc && on_gc_list) {
145 list_del_init(&n->gc_list);
146 atomic_dec(&n->tbl->gc_entries);
147 } else if (!exempt_from_gc && !on_gc_list) {
148 /* add entries to the tail; cleaning removes from the front */
149 list_add_tail(&n->gc_list, &n->tbl->gc_list);
150 atomic_inc(&n->tbl->gc_entries);
151 }
152
153out:
154 write_unlock(&n->lock);
155 write_unlock_bh(&n->tbl->lock);
156}
157
158static bool neigh_update_ext_learned(struct neighbour *neigh, u32 flags,
159 int *notify)
160{
161 bool rc = false;
162 u8 ndm_flags;
163
164 if (!(flags & NEIGH_UPDATE_F_ADMIN))
165 return rc;
166
167 ndm_flags = (flags & NEIGH_UPDATE_F_EXT_LEARNED) ? NTF_EXT_LEARNED : 0;
168 if ((neigh->flags ^ ndm_flags) & NTF_EXT_LEARNED) {
169 if (ndm_flags & NTF_EXT_LEARNED)
170 neigh->flags |= NTF_EXT_LEARNED;
171 else
172 neigh->flags &= ~NTF_EXT_LEARNED;
173 rc = true;
174 *notify = 1;
175 }
176
177 return rc;
178}
179
180static bool neigh_del(struct neighbour *n, struct neighbour __rcu **np,
181 struct neigh_table *tbl)
182{
183 bool retval = false;
184
185 write_lock(&n->lock);
186 if (refcount_read(&n->refcnt) == 1) {
187 struct neighbour *neigh;
188
189 neigh = rcu_dereference_protected(n->next,
190 lockdep_is_held(&tbl->lock));
191 rcu_assign_pointer(*np, neigh);
192 neigh_mark_dead(n);
193 retval = true;
194 }
195 write_unlock(&n->lock);
196 if (retval)
197 neigh_cleanup_and_release(n);
198 return retval;
199}
200
201bool neigh_remove_one(struct neighbour *ndel, struct neigh_table *tbl)
202{
203 struct neigh_hash_table *nht;
204 void *pkey = ndel->primary_key;
205 u32 hash_val;
206 struct neighbour *n;
207 struct neighbour __rcu **np;
208
209 nht = rcu_dereference_protected(tbl->nht,
210 lockdep_is_held(&tbl->lock));
211 hash_val = tbl->hash(pkey, ndel->dev, nht->hash_rnd);
212 hash_val = hash_val >> (32 - nht->hash_shift);
213
214 np = &nht->hash_buckets[hash_val];
215 while ((n = rcu_dereference_protected(*np,
216 lockdep_is_held(&tbl->lock)))) {
217 if (n == ndel)
218 return neigh_del(n, np, tbl);
219 np = &n->next;
220 }
221 return false;
222}
223
224static int neigh_forced_gc(struct neigh_table *tbl)
225{
226 int max_clean = atomic_read(&tbl->gc_entries) - tbl->gc_thresh2;
227 unsigned long tref = jiffies - 5 * HZ;
228 struct neighbour *n, *tmp;
229 int shrunk = 0;
230
231 NEIGH_CACHE_STAT_INC(tbl, forced_gc_runs);
232
233 write_lock_bh(&tbl->lock);
234
235 list_for_each_entry_safe(n, tmp, &tbl->gc_list, gc_list) {
236 if (refcount_read(&n->refcnt) == 1) {
237 bool remove = false;
238
239 write_lock(&n->lock);
240 if ((n->nud_state == NUD_FAILED) ||
241 (n->nud_state == NUD_NOARP) ||
242 (tbl->is_multicast &&
243 tbl->is_multicast(n->primary_key)) ||
244 time_after(tref, n->updated))
245 remove = true;
246 write_unlock(&n->lock);
247
248 if (remove && neigh_remove_one(n, tbl))
249 shrunk++;
250 if (shrunk >= max_clean)
251 break;
252 }
253 }
254
255 tbl->last_flush = jiffies;
256
257 write_unlock_bh(&tbl->lock);
258
259 return shrunk;
260}
261
262static void neigh_add_timer(struct neighbour *n, unsigned long when)
263{
264 neigh_hold(n);
265 if (unlikely(mod_timer(&n->timer, when))) {
266 printk("NEIGH: BUG, double timer add, state is %x\n",
267 n->nud_state);
268 dump_stack();
269 }
270}
271
272static int neigh_del_timer(struct neighbour *n)
273{
274 if ((n->nud_state & NUD_IN_TIMER) &&
275 del_timer(&n->timer)) {
276 neigh_release(n);
277 return 1;
278 }
279 return 0;
280}
281
282static void pneigh_queue_purge(struct sk_buff_head *list)
283{
284 struct sk_buff *skb;
285
286 while ((skb = skb_dequeue(list)) != NULL) {
287 dev_put(skb->dev);
288 kfree_skb(skb);
289 }
290}
291
292static void neigh_flush_dev(struct neigh_table *tbl, struct net_device *dev,
293 bool skip_perm)
294{
295 int i;
296 struct neigh_hash_table *nht;
297
298 nht = rcu_dereference_protected(tbl->nht,
299 lockdep_is_held(&tbl->lock));
300
301 for (i = 0; i < (1 << nht->hash_shift); i++) {
302 struct neighbour *n;
303 struct neighbour __rcu **np = &nht->hash_buckets[i];
304
305 while ((n = rcu_dereference_protected(*np,
306 lockdep_is_held(&tbl->lock))) != NULL) {
307 if (dev && n->dev != dev) {
308 np = &n->next;
309 continue;
310 }
311 if (skip_perm && n->nud_state & NUD_PERMANENT) {
312 np = &n->next;
313 continue;
314 }
315 rcu_assign_pointer(*np,
316 rcu_dereference_protected(n->next,
317 lockdep_is_held(&tbl->lock)));
318 write_lock(&n->lock);
319 neigh_del_timer(n);
320 neigh_mark_dead(n);
321 if (refcount_read(&n->refcnt) != 1) {
322 /* The most unpleasant situation.
323 We must destroy neighbour entry,
324 but someone still uses it.
325
326 The destroy will be delayed until
327 the last user releases us, but
328 we must kill timers etc. and move
329 it to safe state.
330 */
331 __skb_queue_purge(&n->arp_queue);
332 n->arp_queue_len_bytes = 0;
333 n->output = neigh_blackhole;
334 if (n->nud_state & NUD_VALID)
335 n->nud_state = NUD_NOARP;
336 else
337 n->nud_state = NUD_NONE;
338 neigh_dbg(2, "neigh %p is stray\n", n);
339 }
340 write_unlock(&n->lock);
341 neigh_cleanup_and_release(n);
342 }
343 }
344}
345
346void neigh_changeaddr(struct neigh_table *tbl, struct net_device *dev)
347{
348 write_lock_bh(&tbl->lock);
349 neigh_flush_dev(tbl, dev, false);
350 write_unlock_bh(&tbl->lock);
351}
352EXPORT_SYMBOL(neigh_changeaddr);
353
354static int __neigh_ifdown(struct neigh_table *tbl, struct net_device *dev,
355 bool skip_perm)
356{
357 write_lock_bh(&tbl->lock);
358 neigh_flush_dev(tbl, dev, skip_perm);
359 pneigh_ifdown_and_unlock(tbl, dev);
360
361 del_timer_sync(&tbl->proxy_timer);
362 pneigh_queue_purge(&tbl->proxy_queue);
363 return 0;
364}
365
366int neigh_carrier_down(struct neigh_table *tbl, struct net_device *dev)
367{
368 __neigh_ifdown(tbl, dev, true);
369 return 0;
370}
371EXPORT_SYMBOL(neigh_carrier_down);
372
373int neigh_ifdown(struct neigh_table *tbl, struct net_device *dev)
374{
375 __neigh_ifdown(tbl, dev, false);
376 return 0;
377}
378EXPORT_SYMBOL(neigh_ifdown);
379
380static struct neighbour *neigh_alloc(struct neigh_table *tbl,
381 struct net_device *dev,
382 bool exempt_from_gc)
383{
384 struct neighbour *n = NULL;
385 unsigned long now = jiffies;
386 int entries;
387
388 if (exempt_from_gc)
389 goto do_alloc;
390
391 entries = atomic_inc_return(&tbl->gc_entries) - 1;
392 if (entries >= tbl->gc_thresh3 ||
393 (entries >= tbl->gc_thresh2 &&
394 time_after(now, tbl->last_flush + 5 * HZ))) {
395 if (!neigh_forced_gc(tbl) &&
396 entries >= tbl->gc_thresh3) {
397 net_info_ratelimited("%s: neighbor table overflow!\n",
398 tbl->id);
399 NEIGH_CACHE_STAT_INC(tbl, table_fulls);
400 goto out_entries;
401 }
402 }
403
404do_alloc:
405 n = kzalloc(tbl->entry_size + dev->neigh_priv_len, GFP_ATOMIC);
406 if (!n)
407 goto out_entries;
408
409 __skb_queue_head_init(&n->arp_queue);
410 rwlock_init(&n->lock);
411 seqlock_init(&n->ha_lock);
412 n->updated = n->used = now;
413 n->nud_state = NUD_NONE;
414 n->output = neigh_blackhole;
415 seqlock_init(&n->hh.hh_lock);
416 n->parms = neigh_parms_clone(&tbl->parms);
417 timer_setup(&n->timer, neigh_timer_handler, 0);
418
419 NEIGH_CACHE_STAT_INC(tbl, allocs);
420 n->tbl = tbl;
421 refcount_set(&n->refcnt, 1);
422 n->dead = 1;
423 INIT_LIST_HEAD(&n->gc_list);
424
425 atomic_inc(&tbl->entries);
426out:
427 return n;
428
429out_entries:
430 if (!exempt_from_gc)
431 atomic_dec(&tbl->gc_entries);
432 goto out;
433}
434
435static void neigh_get_hash_rnd(u32 *x)
436{
437 *x = get_random_u32() | 1;
438}
439
440static struct neigh_hash_table *neigh_hash_alloc(unsigned int shift)
441{
442 size_t size = (1 << shift) * sizeof(struct neighbour *);
443 struct neigh_hash_table *ret;
444 struct neighbour __rcu **buckets;
445 int i;
446
447 ret = kmalloc(sizeof(*ret), GFP_ATOMIC);
448 if (!ret)
449 return NULL;
450 if (size <= PAGE_SIZE) {
451 buckets = kzalloc(size, GFP_ATOMIC);
452 } else {
453 buckets = (struct neighbour __rcu **)
454 __get_free_pages(GFP_ATOMIC | __GFP_ZERO,
455 get_order(size));
456 kmemleak_alloc(buckets, size, 1, GFP_ATOMIC);
457 }
458 if (!buckets) {
459 kfree(ret);
460 return NULL;
461 }
462 ret->hash_buckets = buckets;
463 ret->hash_shift = shift;
464 for (i = 0; i < NEIGH_NUM_HASH_RND; i++)
465 neigh_get_hash_rnd(&ret->hash_rnd[i]);
466 return ret;
467}
468
469static void neigh_hash_free_rcu(struct rcu_head *head)
470{
471 struct neigh_hash_table *nht = container_of(head,
472 struct neigh_hash_table,
473 rcu);
474 size_t size = (1 << nht->hash_shift) * sizeof(struct neighbour *);
475 struct neighbour __rcu **buckets = nht->hash_buckets;
476
477 if (size <= PAGE_SIZE) {
478 kfree(buckets);
479 } else {
480 kmemleak_free(buckets);
481 free_pages((unsigned long)buckets, get_order(size));
482 }
483 kfree(nht);
484}
485
486static struct neigh_hash_table *neigh_hash_grow(struct neigh_table *tbl,
487 unsigned long new_shift)
488{
489 unsigned int i, hash;
490 struct neigh_hash_table *new_nht, *old_nht;
491
492 NEIGH_CACHE_STAT_INC(tbl, hash_grows);
493
494 old_nht = rcu_dereference_protected(tbl->nht,
495 lockdep_is_held(&tbl->lock));
496 new_nht = neigh_hash_alloc(new_shift);
497 if (!new_nht)
498 return old_nht;
499
500 for (i = 0; i < (1 << old_nht->hash_shift); i++) {
501 struct neighbour *n, *next;
502
503 for (n = rcu_dereference_protected(old_nht->hash_buckets[i],
504 lockdep_is_held(&tbl->lock));
505 n != NULL;
506 n = next) {
507 hash = tbl->hash(n->primary_key, n->dev,
508 new_nht->hash_rnd);
509
510 hash >>= (32 - new_nht->hash_shift);
511 next = rcu_dereference_protected(n->next,
512 lockdep_is_held(&tbl->lock));
513
514 rcu_assign_pointer(n->next,
515 rcu_dereference_protected(
516 new_nht->hash_buckets[hash],
517 lockdep_is_held(&tbl->lock)));
518 rcu_assign_pointer(new_nht->hash_buckets[hash], n);
519 }
520 }
521
522 rcu_assign_pointer(tbl->nht, new_nht);
523 call_rcu(&old_nht->rcu, neigh_hash_free_rcu);
524 return new_nht;
525}
526
527struct neighbour *neigh_lookup(struct neigh_table *tbl, const void *pkey,
528 struct net_device *dev)
529{
530 struct neighbour *n;
531
532 NEIGH_CACHE_STAT_INC(tbl, lookups);
533
534 rcu_read_lock_bh();
535 n = __neigh_lookup_noref(tbl, pkey, dev);
536 if (n) {
537 if (!refcount_inc_not_zero(&n->refcnt))
538 n = NULL;
539 NEIGH_CACHE_STAT_INC(tbl, hits);
540 }
541
542 rcu_read_unlock_bh();
543 return n;
544}
545EXPORT_SYMBOL(neigh_lookup);
546
547struct neighbour *neigh_lookup_nodev(struct neigh_table *tbl, struct net *net,
548 const void *pkey)
549{
550 struct neighbour *n;
551 unsigned int key_len = tbl->key_len;
552 u32 hash_val;
553 struct neigh_hash_table *nht;
554
555 NEIGH_CACHE_STAT_INC(tbl, lookups);
556
557 rcu_read_lock_bh();
558 nht = rcu_dereference_bh(tbl->nht);
559 hash_val = tbl->hash(pkey, NULL, nht->hash_rnd) >> (32 - nht->hash_shift);
560
561 for (n = rcu_dereference_bh(nht->hash_buckets[hash_val]);
562 n != NULL;
563 n = rcu_dereference_bh(n->next)) {
564 if (!memcmp(n->primary_key, pkey, key_len) &&
565 net_eq(dev_net(n->dev), net)) {
566 if (!refcount_inc_not_zero(&n->refcnt))
567 n = NULL;
568 NEIGH_CACHE_STAT_INC(tbl, hits);
569 break;
570 }
571 }
572
573 rcu_read_unlock_bh();
574 return n;
575}
576EXPORT_SYMBOL(neigh_lookup_nodev);
577
578static struct neighbour *___neigh_create(struct neigh_table *tbl,
579 const void *pkey,
580 struct net_device *dev,
581 bool exempt_from_gc, bool want_ref)
582{
583 struct neighbour *n1, *rc, *n = neigh_alloc(tbl, dev, exempt_from_gc);
584 u32 hash_val;
585 unsigned int key_len = tbl->key_len;
586 int error;
587 struct neigh_hash_table *nht;
588
589 trace_neigh_create(tbl, dev, pkey, n, exempt_from_gc);
590
591 if (!n) {
592 rc = ERR_PTR(-ENOBUFS);
593 goto out;
594 }
595
596 memcpy(n->primary_key, pkey, key_len);
597 n->dev = dev;
598 dev_hold(dev);
599
600 /* Protocol specific setup. */
601 if (tbl->constructor && (error = tbl->constructor(n)) < 0) {
602 rc = ERR_PTR(error);
603 goto out_neigh_release;
604 }
605
606 if (dev->netdev_ops->ndo_neigh_construct) {
607 error = dev->netdev_ops->ndo_neigh_construct(dev, n);
608 if (error < 0) {
609 rc = ERR_PTR(error);
610 goto out_neigh_release;
611 }
612 }
613
614 /* Device specific setup. */
615 if (n->parms->neigh_setup &&
616 (error = n->parms->neigh_setup(n)) < 0) {
617 rc = ERR_PTR(error);
618 goto out_neigh_release;
619 }
620
621 n->confirmed = jiffies - (NEIGH_VAR(n->parms, BASE_REACHABLE_TIME) << 1);
622
623 write_lock_bh(&tbl->lock);
624 nht = rcu_dereference_protected(tbl->nht,
625 lockdep_is_held(&tbl->lock));
626
627 if (atomic_read(&tbl->entries) > (1 << nht->hash_shift))
628 nht = neigh_hash_grow(tbl, nht->hash_shift + 1);
629
630 hash_val = tbl->hash(n->primary_key, dev, nht->hash_rnd) >> (32 - nht->hash_shift);
631
632 if (n->parms->dead) {
633 rc = ERR_PTR(-EINVAL);
634 goto out_tbl_unlock;
635 }
636
637 for (n1 = rcu_dereference_protected(nht->hash_buckets[hash_val],
638 lockdep_is_held(&tbl->lock));
639 n1 != NULL;
640 n1 = rcu_dereference_protected(n1->next,
641 lockdep_is_held(&tbl->lock))) {
642 if (dev == n1->dev && !memcmp(n1->primary_key, n->primary_key, key_len)) {
643 if (want_ref)
644 neigh_hold(n1);
645 rc = n1;
646 goto out_tbl_unlock;
647 }
648 }
649
650 n->dead = 0;
651 if (!exempt_from_gc)
652 list_add_tail(&n->gc_list, &n->tbl->gc_list);
653
654 if (want_ref)
655 neigh_hold(n);
656 rcu_assign_pointer(n->next,
657 rcu_dereference_protected(nht->hash_buckets[hash_val],
658 lockdep_is_held(&tbl->lock)));
659 rcu_assign_pointer(nht->hash_buckets[hash_val], n);
660 write_unlock_bh(&tbl->lock);
661 neigh_dbg(2, "neigh %p is created\n", n);
662 rc = n;
663out:
664 return rc;
665out_tbl_unlock:
666 write_unlock_bh(&tbl->lock);
667out_neigh_release:
668 if (!exempt_from_gc)
669 atomic_dec(&tbl->gc_entries);
670 neigh_release(n);
671 goto out;
672}
673
674struct neighbour *__neigh_create(struct neigh_table *tbl, const void *pkey,
675 struct net_device *dev, bool want_ref)
676{
677 return ___neigh_create(tbl, pkey, dev, false, want_ref);
678}
679EXPORT_SYMBOL(__neigh_create);
680
681static u32 pneigh_hash(const void *pkey, unsigned int key_len)
682{
683 u32 hash_val = *(u32 *)(pkey + key_len - 4);
684 hash_val ^= (hash_val >> 16);
685 hash_val ^= hash_val >> 8;
686 hash_val ^= hash_val >> 4;
687 hash_val &= PNEIGH_HASHMASK;
688 return hash_val;
689}
690
691static struct pneigh_entry *__pneigh_lookup_1(struct pneigh_entry *n,
692 struct net *net,
693 const void *pkey,
694 unsigned int key_len,
695 struct net_device *dev)
696{
697 while (n) {
698 if (!memcmp(n->key, pkey, key_len) &&
699 net_eq(pneigh_net(n), net) &&
700 (n->dev == dev || !n->dev))
701 return n;
702 n = n->next;
703 }
704 return NULL;
705}
706
707struct pneigh_entry *__pneigh_lookup(struct neigh_table *tbl,
708 struct net *net, const void *pkey, struct net_device *dev)
709{
710 unsigned int key_len = tbl->key_len;
711 u32 hash_val = pneigh_hash(pkey, key_len);
712
713 return __pneigh_lookup_1(tbl->phash_buckets[hash_val],
714 net, pkey, key_len, dev);
715}
716EXPORT_SYMBOL_GPL(__pneigh_lookup);
717
718struct pneigh_entry * pneigh_lookup(struct neigh_table *tbl,
719 struct net *net, const void *pkey,
720 struct net_device *dev, int creat)
721{
722 struct pneigh_entry *n;
723 unsigned int key_len = tbl->key_len;
724 u32 hash_val = pneigh_hash(pkey, key_len);
725
726 read_lock_bh(&tbl->lock);
727 n = __pneigh_lookup_1(tbl->phash_buckets[hash_val],
728 net, pkey, key_len, dev);
729 read_unlock_bh(&tbl->lock);
730
731 if (n || !creat)
732 goto out;
733
734 ASSERT_RTNL();
735
736 n = kmalloc(sizeof(*n) + key_len, GFP_KERNEL);
737 if (!n)
738 goto out;
739
740 n->protocol = 0;
741 write_pnet(&n->net, net);
742 memcpy(n->key, pkey, key_len);
743 n->dev = dev;
744 if (dev)
745 dev_hold(dev);
746
747 if (tbl->pconstructor && tbl->pconstructor(n)) {
748 if (dev)
749 dev_put(dev);
750 kfree(n);
751 n = NULL;
752 goto out;
753 }
754
755 write_lock_bh(&tbl->lock);
756 n->next = tbl->phash_buckets[hash_val];
757 tbl->phash_buckets[hash_val] = n;
758 write_unlock_bh(&tbl->lock);
759out:
760 return n;
761}
762EXPORT_SYMBOL(pneigh_lookup);
763
764
765int pneigh_delete(struct neigh_table *tbl, struct net *net, const void *pkey,
766 struct net_device *dev)
767{
768 struct pneigh_entry *n, **np;
769 unsigned int key_len = tbl->key_len;
770 u32 hash_val = pneigh_hash(pkey, key_len);
771
772 write_lock_bh(&tbl->lock);
773 for (np = &tbl->phash_buckets[hash_val]; (n = *np) != NULL;
774 np = &n->next) {
775 if (!memcmp(n->key, pkey, key_len) && n->dev == dev &&
776 net_eq(pneigh_net(n), net)) {
777 *np = n->next;
778 write_unlock_bh(&tbl->lock);
779 if (tbl->pdestructor)
780 tbl->pdestructor(n);
781 if (n->dev)
782 dev_put(n->dev);
783 kfree(n);
784 return 0;
785 }
786 }
787 write_unlock_bh(&tbl->lock);
788 return -ENOENT;
789}
790
791static int pneigh_ifdown_and_unlock(struct neigh_table *tbl,
792 struct net_device *dev)
793{
794 struct pneigh_entry *n, **np, *freelist = NULL;
795 u32 h;
796
797 for (h = 0; h <= PNEIGH_HASHMASK; h++) {
798 np = &tbl->phash_buckets[h];
799 while ((n = *np) != NULL) {
800 if (!dev || n->dev == dev) {
801 *np = n->next;
802 n->next = freelist;
803 freelist = n;
804 continue;
805 }
806 np = &n->next;
807 }
808 }
809 write_unlock_bh(&tbl->lock);
810 while ((n = freelist)) {
811 freelist = n->next;
812 n->next = NULL;
813 if (tbl->pdestructor)
814 tbl->pdestructor(n);
815 if (n->dev)
816 dev_put(n->dev);
817 kfree(n);
818 }
819 return -ENOENT;
820}
821
822static void neigh_parms_destroy(struct neigh_parms *parms);
823
824static inline void neigh_parms_put(struct neigh_parms *parms)
825{
826 if (refcount_dec_and_test(&parms->refcnt))
827 neigh_parms_destroy(parms);
828}
829
830/*
831 * neighbour must already be out of the table;
832 *
833 */
834void neigh_destroy(struct neighbour *neigh)
835{
836 struct net_device *dev = neigh->dev;
837
838 NEIGH_CACHE_STAT_INC(neigh->tbl, destroys);
839
840 if (!neigh->dead) {
841 pr_warn("Destroying alive neighbour %p\n", neigh);
842 dump_stack();
843 return;
844 }
845
846 if (neigh_del_timer(neigh))
847 pr_warn("Impossible event\n");
848
849 write_lock_bh(&neigh->lock);
850 __skb_queue_purge(&neigh->arp_queue);
851 write_unlock_bh(&neigh->lock);
852 neigh->arp_queue_len_bytes = 0;
853
854 if (dev->netdev_ops->ndo_neigh_destroy)
855 dev->netdev_ops->ndo_neigh_destroy(dev, neigh);
856
857 dev_put(dev);
858 neigh_parms_put(neigh->parms);
859
860 neigh_dbg(2, "neigh %p is destroyed\n", neigh);
861
862 atomic_dec(&neigh->tbl->entries);
863 kfree_rcu(neigh, rcu);
864}
865EXPORT_SYMBOL(neigh_destroy);
866
867/* Neighbour state is suspicious;
868 disable fast path.
869
870 Called with write_locked neigh.
871 */
872static void neigh_suspect(struct neighbour *neigh)
873{
874 neigh_dbg(2, "neigh %p is suspected\n", neigh);
875
876 neigh->output = neigh->ops->output;
877}
878
879/* Neighbour state is OK;
880 enable fast path.
881
882 Called with write_locked neigh.
883 */
884static void neigh_connect(struct neighbour *neigh)
885{
886 neigh_dbg(2, "neigh %p is connected\n", neigh);
887
888 neigh->output = neigh->ops->connected_output;
889}
890
891static void neigh_periodic_work(struct work_struct *work)
892{
893 struct neigh_table *tbl = container_of(work, struct neigh_table, gc_work.work);
894 struct neighbour *n;
895 struct neighbour __rcu **np;
896 unsigned int i;
897 struct neigh_hash_table *nht;
898
899 NEIGH_CACHE_STAT_INC(tbl, periodic_gc_runs);
900
901 write_lock_bh(&tbl->lock);
902 nht = rcu_dereference_protected(tbl->nht,
903 lockdep_is_held(&tbl->lock));
904
905 /*
906 * periodically recompute ReachableTime from random function
907 */
908
909 if (time_after(jiffies, tbl->last_rand + 300 * HZ)) {
910 struct neigh_parms *p;
911 tbl->last_rand = jiffies;
912 list_for_each_entry(p, &tbl->parms_list, list)
913 p->reachable_time =
914 neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME));
915 }
916
917 if (atomic_read(&tbl->entries) < tbl->gc_thresh1)
918 goto out;
919
920 for (i = 0 ; i < (1 << nht->hash_shift); i++) {
921 np = &nht->hash_buckets[i];
922
923 while ((n = rcu_dereference_protected(*np,
924 lockdep_is_held(&tbl->lock))) != NULL) {
925 unsigned int state;
926
927 write_lock(&n->lock);
928
929 state = n->nud_state;
930 if ((state & (NUD_PERMANENT | NUD_IN_TIMER)) ||
931 (n->flags & NTF_EXT_LEARNED)) {
932 write_unlock(&n->lock);
933 goto next_elt;
934 }
935
936 if (time_before(n->used, n->confirmed))
937 n->used = n->confirmed;
938
939 if (refcount_read(&n->refcnt) == 1 &&
940 (state == NUD_FAILED ||
941 time_after(jiffies, n->used + NEIGH_VAR(n->parms, GC_STALETIME)))) {
942 *np = n->next;
943 neigh_mark_dead(n);
944 write_unlock(&n->lock);
945 neigh_cleanup_and_release(n);
946 continue;
947 }
948 write_unlock(&n->lock);
949
950next_elt:
951 np = &n->next;
952 }
953 /*
954 * It's fine to release lock here, even if hash table
955 * grows while we are preempted.
956 */
957 write_unlock_bh(&tbl->lock);
958 cond_resched();
959 write_lock_bh(&tbl->lock);
960 nht = rcu_dereference_protected(tbl->nht,
961 lockdep_is_held(&tbl->lock));
962 }
963out:
964 /* Cycle through all hash buckets every BASE_REACHABLE_TIME/2 ticks.
965 * ARP entry timeouts range from 1/2 BASE_REACHABLE_TIME to 3/2
966 * BASE_REACHABLE_TIME.
967 */
968 queue_delayed_work(system_power_efficient_wq, &tbl->gc_work,
969 NEIGH_VAR(&tbl->parms, BASE_REACHABLE_TIME) >> 1);
970 write_unlock_bh(&tbl->lock);
971}
972
973static __inline__ int neigh_max_probes(struct neighbour *n)
974{
975 struct neigh_parms *p = n->parms;
976 return NEIGH_VAR(p, UCAST_PROBES) + NEIGH_VAR(p, APP_PROBES) +
977 (n->nud_state & NUD_PROBE ? NEIGH_VAR(p, MCAST_REPROBES) :
978 NEIGH_VAR(p, MCAST_PROBES));
979}
980
981static void neigh_invalidate(struct neighbour *neigh)
982 __releases(neigh->lock)
983 __acquires(neigh->lock)
984{
985 struct sk_buff *skb;
986
987 NEIGH_CACHE_STAT_INC(neigh->tbl, res_failed);
988 neigh_dbg(2, "neigh %p is failed\n", neigh);
989 neigh->updated = jiffies;
990
991 /* It is very thin place. report_unreachable is very complicated
992 routine. Particularly, it can hit the same neighbour entry!
993
994 So that, we try to be accurate and avoid dead loop. --ANK
995 */
996 while (neigh->nud_state == NUD_FAILED &&
997 (skb = __skb_dequeue(&neigh->arp_queue)) != NULL) {
998 write_unlock(&neigh->lock);
999 neigh->ops->error_report(neigh, skb);
1000 write_lock(&neigh->lock);
1001 }
1002 __skb_queue_purge(&neigh->arp_queue);
1003 neigh->arp_queue_len_bytes = 0;
1004}
1005
1006static void neigh_probe(struct neighbour *neigh)
1007 __releases(neigh->lock)
1008{
1009 struct sk_buff *skb = skb_peek_tail(&neigh->arp_queue);
1010 /* keep skb alive even if arp_queue overflows */
1011 if (skb)
1012 skb = skb_clone(skb, GFP_ATOMIC);
1013 write_unlock(&neigh->lock);
1014 if (neigh->ops->solicit)
1015 neigh->ops->solicit(neigh, skb);
1016 atomic_inc(&neigh->probes);
1017 consume_skb(skb);
1018}
1019
1020/* Called when a timer expires for a neighbour entry. */
1021
1022static void neigh_timer_handler(struct timer_list *t)
1023{
1024 unsigned long now, next;
1025 struct neighbour *neigh = from_timer(neigh, t, timer);
1026 unsigned int state;
1027 int notify = 0;
1028
1029 write_lock(&neigh->lock);
1030
1031 state = neigh->nud_state;
1032 now = jiffies;
1033 next = now + HZ;
1034
1035 if (!(state & NUD_IN_TIMER))
1036 goto out;
1037
1038 if (state & NUD_REACHABLE) {
1039 if (time_before_eq(now,
1040 neigh->confirmed + neigh->parms->reachable_time)) {
1041 neigh_dbg(2, "neigh %p is still alive\n", neigh);
1042 next = neigh->confirmed + neigh->parms->reachable_time;
1043 } else if (time_before_eq(now,
1044 neigh->used +
1045 NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME))) {
1046 neigh_dbg(2, "neigh %p is delayed\n", neigh);
1047 neigh->nud_state = NUD_DELAY;
1048 neigh->updated = jiffies;
1049 neigh_suspect(neigh);
1050 next = now + NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME);
1051 } else {
1052 neigh_dbg(2, "neigh %p is suspected\n", neigh);
1053 neigh->nud_state = NUD_STALE;
1054 neigh->updated = jiffies;
1055 neigh_suspect(neigh);
1056 notify = 1;
1057 }
1058 } else if (state & NUD_DELAY) {
1059 if (time_before_eq(now,
1060 neigh->confirmed +
1061 NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME))) {
1062 neigh_dbg(2, "neigh %p is now reachable\n", neigh);
1063 neigh->nud_state = NUD_REACHABLE;
1064 neigh->updated = jiffies;
1065 neigh_connect(neigh);
1066 notify = 1;
1067 next = neigh->confirmed + neigh->parms->reachable_time;
1068 } else {
1069 neigh_dbg(2, "neigh %p is probed\n", neigh);
1070 neigh->nud_state = NUD_PROBE;
1071 neigh->updated = jiffies;
1072 atomic_set(&neigh->probes, 0);
1073 notify = 1;
1074 next = now + max(NEIGH_VAR(neigh->parms, RETRANS_TIME),
1075 HZ/100);
1076 }
1077 } else {
1078 /* NUD_PROBE|NUD_INCOMPLETE */
1079 next = now + max(NEIGH_VAR(neigh->parms, RETRANS_TIME), HZ/100);
1080 }
1081
1082 if ((neigh->nud_state & (NUD_INCOMPLETE | NUD_PROBE)) &&
1083 atomic_read(&neigh->probes) >= neigh_max_probes(neigh)) {
1084 neigh->nud_state = NUD_FAILED;
1085 notify = 1;
1086 neigh_invalidate(neigh);
1087 goto out;
1088 }
1089
1090 if (neigh->nud_state & NUD_IN_TIMER) {
1091 if (time_before(next, jiffies + HZ/100))
1092 next = jiffies + HZ/100;
1093 if (!mod_timer(&neigh->timer, next))
1094 neigh_hold(neigh);
1095 }
1096 if (neigh->nud_state & (NUD_INCOMPLETE | NUD_PROBE)) {
1097 neigh_probe(neigh);
1098 } else {
1099out:
1100 write_unlock(&neigh->lock);
1101 }
1102
1103 if (notify)
1104 neigh_update_notify(neigh, 0);
1105
1106 trace_neigh_timer_handler(neigh, 0);
1107
1108 neigh_release(neigh);
1109}
1110
1111int __neigh_event_send(struct neighbour *neigh, struct sk_buff *skb)
1112{
1113 int rc;
1114 bool immediate_probe = false;
1115
1116 write_lock_bh(&neigh->lock);
1117
1118 rc = 0;
1119 if (neigh->nud_state & (NUD_CONNECTED | NUD_DELAY | NUD_PROBE))
1120 goto out_unlock_bh;
1121 if (neigh->dead)
1122 goto out_dead;
1123
1124 if (!(neigh->nud_state & (NUD_STALE | NUD_INCOMPLETE))) {
1125 if (NEIGH_VAR(neigh->parms, MCAST_PROBES) +
1126 NEIGH_VAR(neigh->parms, APP_PROBES)) {
1127 unsigned long next, now = jiffies;
1128
1129 atomic_set(&neigh->probes,
1130 NEIGH_VAR(neigh->parms, UCAST_PROBES));
1131 neigh_del_timer(neigh);
1132 neigh->nud_state = NUD_INCOMPLETE;
1133 neigh->updated = now;
1134 next = now + max(NEIGH_VAR(neigh->parms, RETRANS_TIME),
1135 HZ/100);
1136 neigh_add_timer(neigh, next);
1137 immediate_probe = true;
1138 } else {
1139 neigh->nud_state = NUD_FAILED;
1140 neigh->updated = jiffies;
1141 write_unlock_bh(&neigh->lock);
1142
1143 kfree_skb(skb);
1144 return 1;
1145 }
1146 } else if (neigh->nud_state & NUD_STALE) {
1147 neigh_dbg(2, "neigh %p is delayed\n", neigh);
1148 neigh_del_timer(neigh);
1149 neigh->nud_state = NUD_DELAY;
1150 neigh->updated = jiffies;
1151 neigh_add_timer(neigh, jiffies +
1152 NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME));
1153 }
1154
1155 if (neigh->nud_state == NUD_INCOMPLETE) {
1156 if (skb) {
1157 while (neigh->arp_queue_len_bytes + skb->truesize >
1158 NEIGH_VAR(neigh->parms, QUEUE_LEN_BYTES)) {
1159 struct sk_buff *buff;
1160
1161 buff = __skb_dequeue(&neigh->arp_queue);
1162 if (!buff)
1163 break;
1164 neigh->arp_queue_len_bytes -= buff->truesize;
1165 kfree_skb(buff);
1166 NEIGH_CACHE_STAT_INC(neigh->tbl, unres_discards);
1167 }
1168 skb_dst_force(skb);
1169 __skb_queue_tail(&neigh->arp_queue, skb);
1170 neigh->arp_queue_len_bytes += skb->truesize;
1171 }
1172 rc = 1;
1173 }
1174out_unlock_bh:
1175 if (immediate_probe)
1176 neigh_probe(neigh);
1177 else
1178 write_unlock(&neigh->lock);
1179 local_bh_enable();
1180 trace_neigh_event_send_done(neigh, rc);
1181 return rc;
1182
1183out_dead:
1184 if (neigh->nud_state & NUD_STALE)
1185 goto out_unlock_bh;
1186 write_unlock_bh(&neigh->lock);
1187 kfree_skb(skb);
1188 trace_neigh_event_send_dead(neigh, 1);
1189 return 1;
1190}
1191EXPORT_SYMBOL(__neigh_event_send);
1192
1193static void neigh_update_hhs(struct neighbour *neigh)
1194{
1195 struct hh_cache *hh;
1196 void (*update)(struct hh_cache*, const struct net_device*, const unsigned char *)
1197 = NULL;
1198
1199 if (neigh->dev->header_ops)
1200 update = neigh->dev->header_ops->cache_update;
1201
1202 if (update) {
1203 hh = &neigh->hh;
1204 if (READ_ONCE(hh->hh_len)) {
1205 write_seqlock_bh(&hh->hh_lock);
1206 update(hh, neigh->dev, neigh->ha);
1207 write_sequnlock_bh(&hh->hh_lock);
1208 }
1209 }
1210}
1211
1212
1213
1214/* Generic update routine.
1215 -- lladdr is new lladdr or NULL, if it is not supplied.
1216 -- new is new state.
1217 -- flags
1218 NEIGH_UPDATE_F_OVERRIDE allows to override existing lladdr,
1219 if it is different.
1220 NEIGH_UPDATE_F_WEAK_OVERRIDE will suspect existing "connected"
1221 lladdr instead of overriding it
1222 if it is different.
1223 NEIGH_UPDATE_F_ADMIN means that the change is administrative.
1224
1225 NEIGH_UPDATE_F_OVERRIDE_ISROUTER allows to override existing
1226 NTF_ROUTER flag.
1227 NEIGH_UPDATE_F_ISROUTER indicates if the neighbour is known as
1228 a router.
1229
1230 Caller MUST hold reference count on the entry.
1231 */
1232
1233static int __neigh_update(struct neighbour *neigh, const u8 *lladdr,
1234 u8 new, u32 flags, u32 nlmsg_pid,
1235 struct netlink_ext_ack *extack)
1236{
1237 bool ext_learn_change = false;
1238 u8 old;
1239 int err;
1240 int notify = 0;
1241 struct net_device *dev;
1242 int update_isrouter = 0;
1243
1244 trace_neigh_update(neigh, lladdr, new, flags, nlmsg_pid);
1245
1246 write_lock_bh(&neigh->lock);
1247
1248 dev = neigh->dev;
1249 old = neigh->nud_state;
1250 err = -EPERM;
1251
1252 if (neigh->dead) {
1253 NL_SET_ERR_MSG(extack, "Neighbor entry is now dead");
1254 new = old;
1255 goto out;
1256 }
1257 if (!(flags & NEIGH_UPDATE_F_ADMIN) &&
1258 (old & (NUD_NOARP | NUD_PERMANENT)))
1259 goto out;
1260
1261 ext_learn_change = neigh_update_ext_learned(neigh, flags, ¬ify);
1262
1263 if (!(new & NUD_VALID)) {
1264 neigh_del_timer(neigh);
1265 if (old & NUD_CONNECTED)
1266 neigh_suspect(neigh);
1267 neigh->nud_state = new;
1268 err = 0;
1269 notify = old & NUD_VALID;
1270 if ((old & (NUD_INCOMPLETE | NUD_PROBE)) &&
1271 (new & NUD_FAILED)) {
1272 neigh_invalidate(neigh);
1273 notify = 1;
1274 }
1275 goto out;
1276 }
1277
1278 /* Compare new lladdr with cached one */
1279 if (!dev->addr_len) {
1280 /* First case: device needs no address. */
1281 lladdr = neigh->ha;
1282 } else if (lladdr) {
1283 /* The second case: if something is already cached
1284 and a new address is proposed:
1285 - compare new & old
1286 - if they are different, check override flag
1287 */
1288 if ((old & NUD_VALID) &&
1289 !memcmp(lladdr, neigh->ha, dev->addr_len))
1290 lladdr = neigh->ha;
1291 } else {
1292 /* No address is supplied; if we know something,
1293 use it, otherwise discard the request.
1294 */
1295 err = -EINVAL;
1296 if (!(old & NUD_VALID)) {
1297 NL_SET_ERR_MSG(extack, "No link layer address given");
1298 goto out;
1299 }
1300 lladdr = neigh->ha;
1301 }
1302
1303 /* Update confirmed timestamp for neighbour entry after we
1304 * received ARP packet even if it doesn't change IP to MAC binding.
1305 */
1306 if (new & NUD_CONNECTED)
1307 neigh->confirmed = jiffies;
1308
1309 /* If entry was valid and address is not changed,
1310 do not change entry state, if new one is STALE.
1311 */
1312 err = 0;
1313 update_isrouter = flags & NEIGH_UPDATE_F_OVERRIDE_ISROUTER;
1314 if (old & NUD_VALID) {
1315 if (lladdr != neigh->ha && !(flags & NEIGH_UPDATE_F_OVERRIDE)) {
1316 update_isrouter = 0;
1317 if ((flags & NEIGH_UPDATE_F_WEAK_OVERRIDE) &&
1318 (old & NUD_CONNECTED)) {
1319 lladdr = neigh->ha;
1320 new = NUD_STALE;
1321 } else
1322 goto out;
1323 } else {
1324 if (lladdr == neigh->ha && new == NUD_STALE &&
1325 !(flags & NEIGH_UPDATE_F_ADMIN))
1326 new = old;
1327 }
1328 }
1329
1330 /* Update timestamp only once we know we will make a change to the
1331 * neighbour entry. Otherwise we risk to move the locktime window with
1332 * noop updates and ignore relevant ARP updates.
1333 */
1334 if (new != old || lladdr != neigh->ha)
1335 neigh->updated = jiffies;
1336
1337 if (new != old) {
1338 neigh_del_timer(neigh);
1339 if (new & NUD_PROBE)
1340 atomic_set(&neigh->probes, 0);
1341 if (new & NUD_IN_TIMER)
1342 neigh_add_timer(neigh, (jiffies +
1343 ((new & NUD_REACHABLE) ?
1344 neigh->parms->reachable_time :
1345 0)));
1346 neigh->nud_state = new;
1347 notify = 1;
1348 }
1349
1350 if (lladdr != neigh->ha) {
1351 write_seqlock(&neigh->ha_lock);
1352 memcpy(&neigh->ha, lladdr, dev->addr_len);
1353 write_sequnlock(&neigh->ha_lock);
1354 neigh_update_hhs(neigh);
1355 if (!(new & NUD_CONNECTED))
1356 neigh->confirmed = jiffies -
1357 (NEIGH_VAR(neigh->parms, BASE_REACHABLE_TIME) << 1);
1358 notify = 1;
1359 }
1360 if (new == old)
1361 goto out;
1362 if (new & NUD_CONNECTED)
1363 neigh_connect(neigh);
1364 else
1365 neigh_suspect(neigh);
1366 if (!(old & NUD_VALID)) {
1367 struct sk_buff *skb;
1368
1369 /* Again: avoid dead loop if something went wrong */
1370
1371 while (neigh->nud_state & NUD_VALID &&
1372 (skb = __skb_dequeue(&neigh->arp_queue)) != NULL) {
1373 struct dst_entry *dst = skb_dst(skb);
1374 struct neighbour *n2, *n1 = neigh;
1375 write_unlock_bh(&neigh->lock);
1376
1377 rcu_read_lock();
1378
1379 /* Why not just use 'neigh' as-is? The problem is that
1380 * things such as shaper, eql, and sch_teql can end up
1381 * using alternative, different, neigh objects to output
1382 * the packet in the output path. So what we need to do
1383 * here is re-lookup the top-level neigh in the path so
1384 * we can reinject the packet there.
1385 */
1386 n2 = NULL;
1387 if (dst && dst->obsolete != DST_OBSOLETE_DEAD) {
1388 n2 = dst_neigh_lookup_skb(dst, skb);
1389 if (n2)
1390 n1 = n2;
1391 }
1392 n1->output(n1, skb);
1393 if (n2)
1394 neigh_release(n2);
1395 rcu_read_unlock();
1396
1397 write_lock_bh(&neigh->lock);
1398 }
1399 __skb_queue_purge(&neigh->arp_queue);
1400 neigh->arp_queue_len_bytes = 0;
1401 }
1402out:
1403 if (update_isrouter)
1404 neigh_update_is_router(neigh, flags, ¬ify);
1405 write_unlock_bh(&neigh->lock);
1406
1407 if (((new ^ old) & NUD_PERMANENT) || ext_learn_change)
1408 neigh_update_gc_list(neigh);
1409
1410 if (notify)
1411 neigh_update_notify(neigh, nlmsg_pid);
1412
1413 trace_neigh_update_done(neigh, err);
1414
1415 return err;
1416}
1417
1418int neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new,
1419 u32 flags, u32 nlmsg_pid)
1420{
1421 return __neigh_update(neigh, lladdr, new, flags, nlmsg_pid, NULL);
1422}
1423EXPORT_SYMBOL(neigh_update);
1424
1425/* Update the neigh to listen temporarily for probe responses, even if it is
1426 * in a NUD_FAILED state. The caller has to hold neigh->lock for writing.
1427 */
1428void __neigh_set_probe_once(struct neighbour *neigh)
1429{
1430 if (neigh->dead)
1431 return;
1432 neigh->updated = jiffies;
1433 if (!(neigh->nud_state & NUD_FAILED))
1434 return;
1435 neigh->nud_state = NUD_INCOMPLETE;
1436 atomic_set(&neigh->probes, neigh_max_probes(neigh));
1437 neigh_add_timer(neigh,
1438 jiffies + max(NEIGH_VAR(neigh->parms, RETRANS_TIME),
1439 HZ/100));
1440}
1441EXPORT_SYMBOL(__neigh_set_probe_once);
1442
1443struct neighbour *neigh_event_ns(struct neigh_table *tbl,
1444 u8 *lladdr, void *saddr,
1445 struct net_device *dev)
1446{
1447 struct neighbour *neigh = __neigh_lookup(tbl, saddr, dev,
1448 lladdr || !dev->addr_len);
1449 if (neigh)
1450 neigh_update(neigh, lladdr, NUD_STALE,
1451 NEIGH_UPDATE_F_OVERRIDE, 0);
1452 return neigh;
1453}
1454EXPORT_SYMBOL(neigh_event_ns);
1455
1456/* called with read_lock_bh(&n->lock); */
1457static void neigh_hh_init(struct neighbour *n)
1458{
1459 struct net_device *dev = n->dev;
1460 __be16 prot = n->tbl->protocol;
1461 struct hh_cache *hh = &n->hh;
1462
1463 write_lock_bh(&n->lock);
1464
1465 /* Only one thread can come in here and initialize the
1466 * hh_cache entry.
1467 */
1468 if (!hh->hh_len)
1469 dev->header_ops->cache(n, hh, prot);
1470
1471 write_unlock_bh(&n->lock);
1472}
1473
1474/* Slow and careful. */
1475
1476int neigh_resolve_output(struct neighbour *neigh, struct sk_buff *skb)
1477{
1478 int rc = 0;
1479
1480 if (!neigh_event_send(neigh, skb)) {
1481 int err;
1482 struct net_device *dev = neigh->dev;
1483 unsigned int seq;
1484
1485 if (dev->header_ops->cache && !READ_ONCE(neigh->hh.hh_len))
1486 neigh_hh_init(neigh);
1487
1488 do {
1489 __skb_pull(skb, skb_network_offset(skb));
1490 seq = read_seqbegin(&neigh->ha_lock);
1491 err = dev_hard_header(skb, dev, ntohs(skb->protocol),
1492 neigh->ha, NULL, skb->len);
1493 } while (read_seqretry(&neigh->ha_lock, seq));
1494
1495 if (err >= 0)
1496 rc = dev_queue_xmit(skb);
1497 else
1498 goto out_kfree_skb;
1499 }
1500out:
1501 return rc;
1502out_kfree_skb:
1503 rc = -EINVAL;
1504 kfree_skb(skb);
1505 goto out;
1506}
1507EXPORT_SYMBOL(neigh_resolve_output);
1508
1509/* As fast as possible without hh cache */
1510
1511int neigh_connected_output(struct neighbour *neigh, struct sk_buff *skb)
1512{
1513 struct net_device *dev = neigh->dev;
1514 unsigned int seq;
1515 int err;
1516
1517 do {
1518 __skb_pull(skb, skb_network_offset(skb));
1519 seq = read_seqbegin(&neigh->ha_lock);
1520 err = dev_hard_header(skb, dev, ntohs(skb->protocol),
1521 neigh->ha, NULL, skb->len);
1522 } while (read_seqretry(&neigh->ha_lock, seq));
1523
1524 if (err >= 0)
1525 err = dev_queue_xmit(skb);
1526 else {
1527 err = -EINVAL;
1528 kfree_skb(skb);
1529 }
1530 return err;
1531}
1532EXPORT_SYMBOL(neigh_connected_output);
1533
1534int neigh_direct_output(struct neighbour *neigh, struct sk_buff *skb)
1535{
1536 return dev_queue_xmit(skb);
1537}
1538EXPORT_SYMBOL(neigh_direct_output);
1539
1540static void neigh_proxy_process(struct timer_list *t)
1541{
1542 struct neigh_table *tbl = from_timer(tbl, t, proxy_timer);
1543 long sched_next = 0;
1544 unsigned long now = jiffies;
1545 struct sk_buff *skb, *n;
1546
1547 spin_lock(&tbl->proxy_queue.lock);
1548
1549 skb_queue_walk_safe(&tbl->proxy_queue, skb, n) {
1550 long tdif = NEIGH_CB(skb)->sched_next - now;
1551
1552 if (tdif <= 0) {
1553 struct net_device *dev = skb->dev;
1554
1555 __skb_unlink(skb, &tbl->proxy_queue);
1556 if (tbl->proxy_redo && netif_running(dev)) {
1557 rcu_read_lock();
1558 tbl->proxy_redo(skb);
1559 rcu_read_unlock();
1560 } else {
1561 kfree_skb(skb);
1562 }
1563
1564 dev_put(dev);
1565 } else if (!sched_next || tdif < sched_next)
1566 sched_next = tdif;
1567 }
1568 del_timer(&tbl->proxy_timer);
1569 if (sched_next)
1570 mod_timer(&tbl->proxy_timer, jiffies + sched_next);
1571 spin_unlock(&tbl->proxy_queue.lock);
1572}
1573
1574void pneigh_enqueue(struct neigh_table *tbl, struct neigh_parms *p,
1575 struct sk_buff *skb)
1576{
1577 unsigned long sched_next = jiffies +
1578 prandom_u32_max(NEIGH_VAR(p, PROXY_DELAY));
1579
1580 if (tbl->proxy_queue.qlen > NEIGH_VAR(p, PROXY_QLEN)) {
1581 kfree_skb(skb);
1582 return;
1583 }
1584
1585 NEIGH_CB(skb)->sched_next = sched_next;
1586 NEIGH_CB(skb)->flags |= LOCALLY_ENQUEUED;
1587
1588 spin_lock(&tbl->proxy_queue.lock);
1589 if (del_timer(&tbl->proxy_timer)) {
1590 if (time_before(tbl->proxy_timer.expires, sched_next))
1591 sched_next = tbl->proxy_timer.expires;
1592 }
1593 skb_dst_drop(skb);
1594 dev_hold(skb->dev);
1595 __skb_queue_tail(&tbl->proxy_queue, skb);
1596 mod_timer(&tbl->proxy_timer, sched_next);
1597 spin_unlock(&tbl->proxy_queue.lock);
1598}
1599EXPORT_SYMBOL(pneigh_enqueue);
1600
1601static inline struct neigh_parms *lookup_neigh_parms(struct neigh_table *tbl,
1602 struct net *net, int ifindex)
1603{
1604 struct neigh_parms *p;
1605
1606 list_for_each_entry(p, &tbl->parms_list, list) {
1607 if ((p->dev && p->dev->ifindex == ifindex && net_eq(neigh_parms_net(p), net)) ||
1608 (!p->dev && !ifindex && net_eq(net, &init_net)))
1609 return p;
1610 }
1611
1612 return NULL;
1613}
1614
1615struct neigh_parms *neigh_parms_alloc(struct net_device *dev,
1616 struct neigh_table *tbl)
1617{
1618 struct neigh_parms *p;
1619 struct net *net = dev_net(dev);
1620 const struct net_device_ops *ops = dev->netdev_ops;
1621
1622 p = kmemdup(&tbl->parms, sizeof(*p), GFP_KERNEL);
1623 if (p) {
1624 p->tbl = tbl;
1625 refcount_set(&p->refcnt, 1);
1626 p->reachable_time =
1627 neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME));
1628 dev_hold(dev);
1629 p->dev = dev;
1630 write_pnet(&p->net, net);
1631 p->sysctl_table = NULL;
1632
1633 if (ops->ndo_neigh_setup && ops->ndo_neigh_setup(dev, p)) {
1634 dev_put(dev);
1635 kfree(p);
1636 return NULL;
1637 }
1638
1639 write_lock_bh(&tbl->lock);
1640 list_add(&p->list, &tbl->parms.list);
1641 write_unlock_bh(&tbl->lock);
1642
1643 neigh_parms_data_state_cleanall(p);
1644 }
1645 return p;
1646}
1647EXPORT_SYMBOL(neigh_parms_alloc);
1648
1649static void neigh_rcu_free_parms(struct rcu_head *head)
1650{
1651 struct neigh_parms *parms =
1652 container_of(head, struct neigh_parms, rcu_head);
1653
1654 neigh_parms_put(parms);
1655}
1656
1657void neigh_parms_release(struct neigh_table *tbl, struct neigh_parms *parms)
1658{
1659 if (!parms || parms == &tbl->parms)
1660 return;
1661 write_lock_bh(&tbl->lock);
1662 list_del(&parms->list);
1663 parms->dead = 1;
1664 write_unlock_bh(&tbl->lock);
1665 if (parms->dev)
1666 dev_put(parms->dev);
1667 call_rcu(&parms->rcu_head, neigh_rcu_free_parms);
1668}
1669EXPORT_SYMBOL(neigh_parms_release);
1670
1671static void neigh_parms_destroy(struct neigh_parms *parms)
1672{
1673 kfree(parms);
1674}
1675
1676static struct lock_class_key neigh_table_proxy_queue_class;
1677
1678static struct neigh_table *neigh_tables[NEIGH_NR_TABLES] __read_mostly;
1679
1680void neigh_table_init(int index, struct neigh_table *tbl)
1681{
1682 unsigned long now = jiffies;
1683 unsigned long phsize;
1684
1685 INIT_LIST_HEAD(&tbl->parms_list);
1686 INIT_LIST_HEAD(&tbl->gc_list);
1687 list_add(&tbl->parms.list, &tbl->parms_list);
1688 write_pnet(&tbl->parms.net, &init_net);
1689 refcount_set(&tbl->parms.refcnt, 1);
1690 tbl->parms.reachable_time =
1691 neigh_rand_reach_time(NEIGH_VAR(&tbl->parms, BASE_REACHABLE_TIME));
1692
1693 tbl->stats = alloc_percpu(struct neigh_statistics);
1694 if (!tbl->stats)
1695 panic("cannot create neighbour cache statistics");
1696
1697#ifdef CONFIG_PROC_FS
1698 if (!proc_create_seq_data(tbl->id, 0, init_net.proc_net_stat,
1699 &neigh_stat_seq_ops, tbl))
1700 panic("cannot create neighbour proc dir entry");
1701#endif
1702
1703 RCU_INIT_POINTER(tbl->nht, neigh_hash_alloc(3));
1704
1705 phsize = (PNEIGH_HASHMASK + 1) * sizeof(struct pneigh_entry *);
1706 tbl->phash_buckets = kzalloc(phsize, GFP_KERNEL);
1707
1708 if (!tbl->nht || !tbl->phash_buckets)
1709 panic("cannot allocate neighbour cache hashes");
1710
1711 if (!tbl->entry_size)
1712 tbl->entry_size = ALIGN(offsetof(struct neighbour, primary_key) +
1713 tbl->key_len, NEIGH_PRIV_ALIGN);
1714 else
1715 WARN_ON(tbl->entry_size % NEIGH_PRIV_ALIGN);
1716
1717 rwlock_init(&tbl->lock);
1718 INIT_DEFERRABLE_WORK(&tbl->gc_work, neigh_periodic_work);
1719 queue_delayed_work(system_power_efficient_wq, &tbl->gc_work,
1720 tbl->parms.reachable_time);
1721 timer_setup(&tbl->proxy_timer, neigh_proxy_process, 0);
1722 skb_queue_head_init_class(&tbl->proxy_queue,
1723 &neigh_table_proxy_queue_class);
1724
1725 tbl->last_flush = now;
1726 tbl->last_rand = now + tbl->parms.reachable_time * 20;
1727
1728 neigh_tables[index] = tbl;
1729}
1730EXPORT_SYMBOL(neigh_table_init);
1731
1732int neigh_table_clear(int index, struct neigh_table *tbl)
1733{
1734 neigh_tables[index] = NULL;
1735 /* It is not clean... Fix it to unload IPv6 module safely */
1736 cancel_delayed_work_sync(&tbl->gc_work);
1737 del_timer_sync(&tbl->proxy_timer);
1738 pneigh_queue_purge(&tbl->proxy_queue);
1739 neigh_ifdown(tbl, NULL);
1740 if (atomic_read(&tbl->entries))
1741 pr_crit("neighbour leakage\n");
1742
1743 call_rcu(&rcu_dereference_protected(tbl->nht, 1)->rcu,
1744 neigh_hash_free_rcu);
1745 tbl->nht = NULL;
1746
1747 kfree(tbl->phash_buckets);
1748 tbl->phash_buckets = NULL;
1749
1750 remove_proc_entry(tbl->id, init_net.proc_net_stat);
1751
1752 free_percpu(tbl->stats);
1753 tbl->stats = NULL;
1754
1755 return 0;
1756}
1757EXPORT_SYMBOL(neigh_table_clear);
1758
1759static struct neigh_table *neigh_find_table(int family)
1760{
1761 struct neigh_table *tbl = NULL;
1762
1763 switch (family) {
1764 case AF_INET:
1765 tbl = neigh_tables[NEIGH_ARP_TABLE];
1766 break;
1767 case AF_INET6:
1768 tbl = neigh_tables[NEIGH_ND_TABLE];
1769 break;
1770 case AF_DECnet:
1771 tbl = neigh_tables[NEIGH_DN_TABLE];
1772 break;
1773 }
1774
1775 return tbl;
1776}
1777
1778const struct nla_policy nda_policy[NDA_MAX+1] = {
1779 [NDA_UNSPEC] = { .strict_start_type = NDA_NH_ID },
1780 [NDA_DST] = { .type = NLA_BINARY, .len = MAX_ADDR_LEN },
1781 [NDA_LLADDR] = { .type = NLA_BINARY, .len = MAX_ADDR_LEN },
1782 [NDA_CACHEINFO] = { .len = sizeof(struct nda_cacheinfo) },
1783 [NDA_PROBES] = { .type = NLA_U32 },
1784 [NDA_VLAN] = { .type = NLA_U16 },
1785 [NDA_PORT] = { .type = NLA_U16 },
1786 [NDA_VNI] = { .type = NLA_U32 },
1787 [NDA_IFINDEX] = { .type = NLA_U32 },
1788 [NDA_MASTER] = { .type = NLA_U32 },
1789 [NDA_PROTOCOL] = { .type = NLA_U8 },
1790 [NDA_NH_ID] = { .type = NLA_U32 },
1791 [NDA_FDB_EXT_ATTRS] = { .type = NLA_NESTED },
1792};
1793
1794static int neigh_delete(struct sk_buff *skb, struct nlmsghdr *nlh,
1795 struct netlink_ext_ack *extack)
1796{
1797 struct net *net = sock_net(skb->sk);
1798 struct ndmsg *ndm;
1799 struct nlattr *dst_attr;
1800 struct neigh_table *tbl;
1801 struct neighbour *neigh;
1802 struct net_device *dev = NULL;
1803 int err = -EINVAL;
1804
1805 ASSERT_RTNL();
1806 if (nlmsg_len(nlh) < sizeof(*ndm))
1807 goto out;
1808
1809 dst_attr = nlmsg_find_attr(nlh, sizeof(*ndm), NDA_DST);
1810 if (!dst_attr) {
1811 NL_SET_ERR_MSG(extack, "Network address not specified");
1812 goto out;
1813 }
1814
1815 ndm = nlmsg_data(nlh);
1816 if (ndm->ndm_ifindex) {
1817 dev = __dev_get_by_index(net, ndm->ndm_ifindex);
1818 if (dev == NULL) {
1819 err = -ENODEV;
1820 goto out;
1821 }
1822 }
1823
1824 tbl = neigh_find_table(ndm->ndm_family);
1825 if (tbl == NULL)
1826 return -EAFNOSUPPORT;
1827
1828 if (nla_len(dst_attr) < (int)tbl->key_len) {
1829 NL_SET_ERR_MSG(extack, "Invalid network address");
1830 goto out;
1831 }
1832
1833 if (ndm->ndm_flags & NTF_PROXY) {
1834 err = pneigh_delete(tbl, net, nla_data(dst_attr), dev);
1835 goto out;
1836 }
1837
1838 if (dev == NULL)
1839 goto out;
1840
1841 neigh = neigh_lookup(tbl, nla_data(dst_attr), dev);
1842 if (neigh == NULL) {
1843 err = -ENOENT;
1844 goto out;
1845 }
1846
1847 err = __neigh_update(neigh, NULL, NUD_FAILED,
1848 NEIGH_UPDATE_F_OVERRIDE | NEIGH_UPDATE_F_ADMIN,
1849 NETLINK_CB(skb).portid, extack);
1850 write_lock_bh(&tbl->lock);
1851 neigh_release(neigh);
1852 neigh_remove_one(neigh, tbl);
1853 write_unlock_bh(&tbl->lock);
1854
1855out:
1856 return err;
1857}
1858
1859static int neigh_add(struct sk_buff *skb, struct nlmsghdr *nlh,
1860 struct netlink_ext_ack *extack)
1861{
1862 int flags = NEIGH_UPDATE_F_ADMIN | NEIGH_UPDATE_F_OVERRIDE |
1863 NEIGH_UPDATE_F_OVERRIDE_ISROUTER;
1864 struct net *net = sock_net(skb->sk);
1865 struct ndmsg *ndm;
1866 struct nlattr *tb[NDA_MAX+1];
1867 struct neigh_table *tbl;
1868 struct net_device *dev = NULL;
1869 struct neighbour *neigh;
1870 void *dst, *lladdr;
1871 u8 protocol = 0;
1872 int err;
1873
1874 ASSERT_RTNL();
1875 err = nlmsg_parse_deprecated(nlh, sizeof(*ndm), tb, NDA_MAX,
1876 nda_policy, extack);
1877 if (err < 0)
1878 goto out;
1879
1880 err = -EINVAL;
1881 if (!tb[NDA_DST]) {
1882 NL_SET_ERR_MSG(extack, "Network address not specified");
1883 goto out;
1884 }
1885
1886 ndm = nlmsg_data(nlh);
1887 if (ndm->ndm_ifindex) {
1888 dev = __dev_get_by_index(net, ndm->ndm_ifindex);
1889 if (dev == NULL) {
1890 err = -ENODEV;
1891 goto out;
1892 }
1893
1894 if (tb[NDA_LLADDR] && nla_len(tb[NDA_LLADDR]) < dev->addr_len) {
1895 NL_SET_ERR_MSG(extack, "Invalid link address");
1896 goto out;
1897 }
1898 }
1899
1900 tbl = neigh_find_table(ndm->ndm_family);
1901 if (tbl == NULL)
1902 return -EAFNOSUPPORT;
1903
1904 if (nla_len(tb[NDA_DST]) < (int)tbl->key_len) {
1905 NL_SET_ERR_MSG(extack, "Invalid network address");
1906 goto out;
1907 }
1908
1909 dst = nla_data(tb[NDA_DST]);
1910 lladdr = tb[NDA_LLADDR] ? nla_data(tb[NDA_LLADDR]) : NULL;
1911
1912 if (tb[NDA_PROTOCOL])
1913 protocol = nla_get_u8(tb[NDA_PROTOCOL]);
1914
1915 if (ndm->ndm_flags & NTF_PROXY) {
1916 struct pneigh_entry *pn;
1917
1918 err = -ENOBUFS;
1919 pn = pneigh_lookup(tbl, net, dst, dev, 1);
1920 if (pn) {
1921 pn->flags = ndm->ndm_flags;
1922 if (protocol)
1923 pn->protocol = protocol;
1924 err = 0;
1925 }
1926 goto out;
1927 }
1928
1929 if (!dev) {
1930 NL_SET_ERR_MSG(extack, "Device not specified");
1931 goto out;
1932 }
1933
1934 if (tbl->allow_add && !tbl->allow_add(dev, extack)) {
1935 err = -EINVAL;
1936 goto out;
1937 }
1938
1939 neigh = neigh_lookup(tbl, dst, dev);
1940 if (neigh == NULL) {
1941 bool exempt_from_gc;
1942
1943 if (!(nlh->nlmsg_flags & NLM_F_CREATE)) {
1944 err = -ENOENT;
1945 goto out;
1946 }
1947
1948 exempt_from_gc = ndm->ndm_state & NUD_PERMANENT ||
1949 ndm->ndm_flags & NTF_EXT_LEARNED;
1950 neigh = ___neigh_create(tbl, dst, dev, exempt_from_gc, true);
1951 if (IS_ERR(neigh)) {
1952 err = PTR_ERR(neigh);
1953 goto out;
1954 }
1955 } else {
1956 if (nlh->nlmsg_flags & NLM_F_EXCL) {
1957 err = -EEXIST;
1958 neigh_release(neigh);
1959 goto out;
1960 }
1961
1962 if (!(nlh->nlmsg_flags & NLM_F_REPLACE))
1963 flags &= ~(NEIGH_UPDATE_F_OVERRIDE |
1964 NEIGH_UPDATE_F_OVERRIDE_ISROUTER);
1965 }
1966
1967 if (protocol)
1968 neigh->protocol = protocol;
1969
1970 if (ndm->ndm_flags & NTF_EXT_LEARNED)
1971 flags |= NEIGH_UPDATE_F_EXT_LEARNED;
1972
1973 if (ndm->ndm_flags & NTF_ROUTER)
1974 flags |= NEIGH_UPDATE_F_ISROUTER;
1975
1976 if (ndm->ndm_flags & NTF_USE) {
1977 neigh_event_send(neigh, NULL);
1978 err = 0;
1979 } else
1980 err = __neigh_update(neigh, lladdr, ndm->ndm_state, flags,
1981 NETLINK_CB(skb).portid, extack);
1982
1983 neigh_release(neigh);
1984
1985out:
1986 return err;
1987}
1988
1989static int neightbl_fill_parms(struct sk_buff *skb, struct neigh_parms *parms)
1990{
1991 struct nlattr *nest;
1992
1993 nest = nla_nest_start_noflag(skb, NDTA_PARMS);
1994 if (nest == NULL)
1995 return -ENOBUFS;
1996
1997 if ((parms->dev &&
1998 nla_put_u32(skb, NDTPA_IFINDEX, parms->dev->ifindex)) ||
1999 nla_put_u32(skb, NDTPA_REFCNT, refcount_read(&parms->refcnt)) ||
2000 nla_put_u32(skb, NDTPA_QUEUE_LENBYTES,
2001 NEIGH_VAR(parms, QUEUE_LEN_BYTES)) ||
2002 /* approximative value for deprecated QUEUE_LEN (in packets) */
2003 nla_put_u32(skb, NDTPA_QUEUE_LEN,
2004 NEIGH_VAR(parms, QUEUE_LEN_BYTES) / SKB_TRUESIZE(ETH_FRAME_LEN)) ||
2005 nla_put_u32(skb, NDTPA_PROXY_QLEN, NEIGH_VAR(parms, PROXY_QLEN)) ||
2006 nla_put_u32(skb, NDTPA_APP_PROBES, NEIGH_VAR(parms, APP_PROBES)) ||
2007 nla_put_u32(skb, NDTPA_UCAST_PROBES,
2008 NEIGH_VAR(parms, UCAST_PROBES)) ||
2009 nla_put_u32(skb, NDTPA_MCAST_PROBES,
2010 NEIGH_VAR(parms, MCAST_PROBES)) ||
2011 nla_put_u32(skb, NDTPA_MCAST_REPROBES,
2012 NEIGH_VAR(parms, MCAST_REPROBES)) ||
2013 nla_put_msecs(skb, NDTPA_REACHABLE_TIME, parms->reachable_time,
2014 NDTPA_PAD) ||
2015 nla_put_msecs(skb, NDTPA_BASE_REACHABLE_TIME,
2016 NEIGH_VAR(parms, BASE_REACHABLE_TIME), NDTPA_PAD) ||
2017 nla_put_msecs(skb, NDTPA_GC_STALETIME,
2018 NEIGH_VAR(parms, GC_STALETIME), NDTPA_PAD) ||
2019 nla_put_msecs(skb, NDTPA_DELAY_PROBE_TIME,
2020 NEIGH_VAR(parms, DELAY_PROBE_TIME), NDTPA_PAD) ||
2021 nla_put_msecs(skb, NDTPA_RETRANS_TIME,
2022 NEIGH_VAR(parms, RETRANS_TIME), NDTPA_PAD) ||
2023 nla_put_msecs(skb, NDTPA_ANYCAST_DELAY,
2024 NEIGH_VAR(parms, ANYCAST_DELAY), NDTPA_PAD) ||
2025 nla_put_msecs(skb, NDTPA_PROXY_DELAY,
2026 NEIGH_VAR(parms, PROXY_DELAY), NDTPA_PAD) ||
2027 nla_put_msecs(skb, NDTPA_LOCKTIME,
2028 NEIGH_VAR(parms, LOCKTIME), NDTPA_PAD))
2029 goto nla_put_failure;
2030 return nla_nest_end(skb, nest);
2031
2032nla_put_failure:
2033 nla_nest_cancel(skb, nest);
2034 return -EMSGSIZE;
2035}
2036
2037static int neightbl_fill_info(struct sk_buff *skb, struct neigh_table *tbl,
2038 u32 pid, u32 seq, int type, int flags)
2039{
2040 struct nlmsghdr *nlh;
2041 struct ndtmsg *ndtmsg;
2042
2043 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndtmsg), flags);
2044 if (nlh == NULL)
2045 return -EMSGSIZE;
2046
2047 ndtmsg = nlmsg_data(nlh);
2048
2049 read_lock_bh(&tbl->lock);
2050 ndtmsg->ndtm_family = tbl->family;
2051 ndtmsg->ndtm_pad1 = 0;
2052 ndtmsg->ndtm_pad2 = 0;
2053
2054 if (nla_put_string(skb, NDTA_NAME, tbl->id) ||
2055 nla_put_msecs(skb, NDTA_GC_INTERVAL, tbl->gc_interval, NDTA_PAD) ||
2056 nla_put_u32(skb, NDTA_THRESH1, tbl->gc_thresh1) ||
2057 nla_put_u32(skb, NDTA_THRESH2, tbl->gc_thresh2) ||
2058 nla_put_u32(skb, NDTA_THRESH3, tbl->gc_thresh3))
2059 goto nla_put_failure;
2060 {
2061 unsigned long now = jiffies;
2062 long flush_delta = now - tbl->last_flush;
2063 long rand_delta = now - tbl->last_rand;
2064 struct neigh_hash_table *nht;
2065 struct ndt_config ndc = {
2066 .ndtc_key_len = tbl->key_len,
2067 .ndtc_entry_size = tbl->entry_size,
2068 .ndtc_entries = atomic_read(&tbl->entries),
2069 .ndtc_last_flush = jiffies_to_msecs(flush_delta),
2070 .ndtc_last_rand = jiffies_to_msecs(rand_delta),
2071 .ndtc_proxy_qlen = tbl->proxy_queue.qlen,
2072 };
2073
2074 rcu_read_lock_bh();
2075 nht = rcu_dereference_bh(tbl->nht);
2076 ndc.ndtc_hash_rnd = nht->hash_rnd[0];
2077 ndc.ndtc_hash_mask = ((1 << nht->hash_shift) - 1);
2078 rcu_read_unlock_bh();
2079
2080 if (nla_put(skb, NDTA_CONFIG, sizeof(ndc), &ndc))
2081 goto nla_put_failure;
2082 }
2083
2084 {
2085 int cpu;
2086 struct ndt_stats ndst;
2087
2088 memset(&ndst, 0, sizeof(ndst));
2089
2090 for_each_possible_cpu(cpu) {
2091 struct neigh_statistics *st;
2092
2093 st = per_cpu_ptr(tbl->stats, cpu);
2094 ndst.ndts_allocs += st->allocs;
2095 ndst.ndts_destroys += st->destroys;
2096 ndst.ndts_hash_grows += st->hash_grows;
2097 ndst.ndts_res_failed += st->res_failed;
2098 ndst.ndts_lookups += st->lookups;
2099 ndst.ndts_hits += st->hits;
2100 ndst.ndts_rcv_probes_mcast += st->rcv_probes_mcast;
2101 ndst.ndts_rcv_probes_ucast += st->rcv_probes_ucast;
2102 ndst.ndts_periodic_gc_runs += st->periodic_gc_runs;
2103 ndst.ndts_forced_gc_runs += st->forced_gc_runs;
2104 ndst.ndts_table_fulls += st->table_fulls;
2105 }
2106
2107 if (nla_put_64bit(skb, NDTA_STATS, sizeof(ndst), &ndst,
2108 NDTA_PAD))
2109 goto nla_put_failure;
2110 }
2111
2112 BUG_ON(tbl->parms.dev);
2113 if (neightbl_fill_parms(skb, &tbl->parms) < 0)
2114 goto nla_put_failure;
2115
2116 read_unlock_bh(&tbl->lock);
2117 nlmsg_end(skb, nlh);
2118 return 0;
2119
2120nla_put_failure:
2121 read_unlock_bh(&tbl->lock);
2122 nlmsg_cancel(skb, nlh);
2123 return -EMSGSIZE;
2124}
2125
2126static int neightbl_fill_param_info(struct sk_buff *skb,
2127 struct neigh_table *tbl,
2128 struct neigh_parms *parms,
2129 u32 pid, u32 seq, int type,
2130 unsigned int flags)
2131{
2132 struct ndtmsg *ndtmsg;
2133 struct nlmsghdr *nlh;
2134
2135 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndtmsg), flags);
2136 if (nlh == NULL)
2137 return -EMSGSIZE;
2138
2139 ndtmsg = nlmsg_data(nlh);
2140
2141 read_lock_bh(&tbl->lock);
2142 ndtmsg->ndtm_family = tbl->family;
2143 ndtmsg->ndtm_pad1 = 0;
2144 ndtmsg->ndtm_pad2 = 0;
2145
2146 if (nla_put_string(skb, NDTA_NAME, tbl->id) < 0 ||
2147 neightbl_fill_parms(skb, parms) < 0)
2148 goto errout;
2149
2150 read_unlock_bh(&tbl->lock);
2151 nlmsg_end(skb, nlh);
2152 return 0;
2153errout:
2154 read_unlock_bh(&tbl->lock);
2155 nlmsg_cancel(skb, nlh);
2156 return -EMSGSIZE;
2157}
2158
2159static const struct nla_policy nl_neightbl_policy[NDTA_MAX+1] = {
2160 [NDTA_NAME] = { .type = NLA_STRING },
2161 [NDTA_THRESH1] = { .type = NLA_U32 },
2162 [NDTA_THRESH2] = { .type = NLA_U32 },
2163 [NDTA_THRESH3] = { .type = NLA_U32 },
2164 [NDTA_GC_INTERVAL] = { .type = NLA_U64 },
2165 [NDTA_PARMS] = { .type = NLA_NESTED },
2166};
2167
2168static const struct nla_policy nl_ntbl_parm_policy[NDTPA_MAX+1] = {
2169 [NDTPA_IFINDEX] = { .type = NLA_U32 },
2170 [NDTPA_QUEUE_LEN] = { .type = NLA_U32 },
2171 [NDTPA_PROXY_QLEN] = { .type = NLA_U32 },
2172 [NDTPA_APP_PROBES] = { .type = NLA_U32 },
2173 [NDTPA_UCAST_PROBES] = { .type = NLA_U32 },
2174 [NDTPA_MCAST_PROBES] = { .type = NLA_U32 },
2175 [NDTPA_MCAST_REPROBES] = { .type = NLA_U32 },
2176 [NDTPA_BASE_REACHABLE_TIME] = { .type = NLA_U64 },
2177 [NDTPA_GC_STALETIME] = { .type = NLA_U64 },
2178 [NDTPA_DELAY_PROBE_TIME] = { .type = NLA_U64 },
2179 [NDTPA_RETRANS_TIME] = { .type = NLA_U64 },
2180 [NDTPA_ANYCAST_DELAY] = { .type = NLA_U64 },
2181 [NDTPA_PROXY_DELAY] = { .type = NLA_U64 },
2182 [NDTPA_LOCKTIME] = { .type = NLA_U64 },
2183};
2184
2185static int neightbl_set(struct sk_buff *skb, struct nlmsghdr *nlh,
2186 struct netlink_ext_ack *extack)
2187{
2188 struct net *net = sock_net(skb->sk);
2189 struct neigh_table *tbl;
2190 struct ndtmsg *ndtmsg;
2191 struct nlattr *tb[NDTA_MAX+1];
2192 bool found = false;
2193 int err, tidx;
2194
2195 err = nlmsg_parse_deprecated(nlh, sizeof(*ndtmsg), tb, NDTA_MAX,
2196 nl_neightbl_policy, extack);
2197 if (err < 0)
2198 goto errout;
2199
2200 if (tb[NDTA_NAME] == NULL) {
2201 err = -EINVAL;
2202 goto errout;
2203 }
2204
2205 ndtmsg = nlmsg_data(nlh);
2206
2207 for (tidx = 0; tidx < NEIGH_NR_TABLES; tidx++) {
2208 tbl = neigh_tables[tidx];
2209 if (!tbl)
2210 continue;
2211 if (ndtmsg->ndtm_family && tbl->family != ndtmsg->ndtm_family)
2212 continue;
2213 if (nla_strcmp(tb[NDTA_NAME], tbl->id) == 0) {
2214 found = true;
2215 break;
2216 }
2217 }
2218
2219 if (!found)
2220 return -ENOENT;
2221
2222 /*
2223 * We acquire tbl->lock to be nice to the periodic timers and
2224 * make sure they always see a consistent set of values.
2225 */
2226 write_lock_bh(&tbl->lock);
2227
2228 if (tb[NDTA_PARMS]) {
2229 struct nlattr *tbp[NDTPA_MAX+1];
2230 struct neigh_parms *p;
2231 int i, ifindex = 0;
2232
2233 err = nla_parse_nested_deprecated(tbp, NDTPA_MAX,
2234 tb[NDTA_PARMS],
2235 nl_ntbl_parm_policy, extack);
2236 if (err < 0)
2237 goto errout_tbl_lock;
2238
2239 if (tbp[NDTPA_IFINDEX])
2240 ifindex = nla_get_u32(tbp[NDTPA_IFINDEX]);
2241
2242 p = lookup_neigh_parms(tbl, net, ifindex);
2243 if (p == NULL) {
2244 err = -ENOENT;
2245 goto errout_tbl_lock;
2246 }
2247
2248 for (i = 1; i <= NDTPA_MAX; i++) {
2249 if (tbp[i] == NULL)
2250 continue;
2251
2252 switch (i) {
2253 case NDTPA_QUEUE_LEN:
2254 NEIGH_VAR_SET(p, QUEUE_LEN_BYTES,
2255 nla_get_u32(tbp[i]) *
2256 SKB_TRUESIZE(ETH_FRAME_LEN));
2257 break;
2258 case NDTPA_QUEUE_LENBYTES:
2259 NEIGH_VAR_SET(p, QUEUE_LEN_BYTES,
2260 nla_get_u32(tbp[i]));
2261 break;
2262 case NDTPA_PROXY_QLEN:
2263 NEIGH_VAR_SET(p, PROXY_QLEN,
2264 nla_get_u32(tbp[i]));
2265 break;
2266 case NDTPA_APP_PROBES:
2267 NEIGH_VAR_SET(p, APP_PROBES,
2268 nla_get_u32(tbp[i]));
2269 break;
2270 case NDTPA_UCAST_PROBES:
2271 NEIGH_VAR_SET(p, UCAST_PROBES,
2272 nla_get_u32(tbp[i]));
2273 break;
2274 case NDTPA_MCAST_PROBES:
2275 NEIGH_VAR_SET(p, MCAST_PROBES,
2276 nla_get_u32(tbp[i]));
2277 break;
2278 case NDTPA_MCAST_REPROBES:
2279 NEIGH_VAR_SET(p, MCAST_REPROBES,
2280 nla_get_u32(tbp[i]));
2281 break;
2282 case NDTPA_BASE_REACHABLE_TIME:
2283 NEIGH_VAR_SET(p, BASE_REACHABLE_TIME,
2284 nla_get_msecs(tbp[i]));
2285 /* update reachable_time as well, otherwise, the change will
2286 * only be effective after the next time neigh_periodic_work
2287 * decides to recompute it (can be multiple minutes)
2288 */
2289 p->reachable_time =
2290 neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME));
2291 break;
2292 case NDTPA_GC_STALETIME:
2293 NEIGH_VAR_SET(p, GC_STALETIME,
2294 nla_get_msecs(tbp[i]));
2295 break;
2296 case NDTPA_DELAY_PROBE_TIME:
2297 NEIGH_VAR_SET(p, DELAY_PROBE_TIME,
2298 nla_get_msecs(tbp[i]));
2299 call_netevent_notifiers(NETEVENT_DELAY_PROBE_TIME_UPDATE, p);
2300 break;
2301 case NDTPA_RETRANS_TIME:
2302 NEIGH_VAR_SET(p, RETRANS_TIME,
2303 nla_get_msecs(tbp[i]));
2304 break;
2305 case NDTPA_ANYCAST_DELAY:
2306 NEIGH_VAR_SET(p, ANYCAST_DELAY,
2307 nla_get_msecs(tbp[i]));
2308 break;
2309 case NDTPA_PROXY_DELAY:
2310 NEIGH_VAR_SET(p, PROXY_DELAY,
2311 nla_get_msecs(tbp[i]));
2312 break;
2313 case NDTPA_LOCKTIME:
2314 NEIGH_VAR_SET(p, LOCKTIME,
2315 nla_get_msecs(tbp[i]));
2316 break;
2317 }
2318 }
2319 }
2320
2321 err = -ENOENT;
2322 if ((tb[NDTA_THRESH1] || tb[NDTA_THRESH2] ||
2323 tb[NDTA_THRESH3] || tb[NDTA_GC_INTERVAL]) &&
2324 !net_eq(net, &init_net))
2325 goto errout_tbl_lock;
2326
2327 if (tb[NDTA_THRESH1])
2328 tbl->gc_thresh1 = nla_get_u32(tb[NDTA_THRESH1]);
2329
2330 if (tb[NDTA_THRESH2])
2331 tbl->gc_thresh2 = nla_get_u32(tb[NDTA_THRESH2]);
2332
2333 if (tb[NDTA_THRESH3])
2334 tbl->gc_thresh3 = nla_get_u32(tb[NDTA_THRESH3]);
2335
2336 if (tb[NDTA_GC_INTERVAL])
2337 tbl->gc_interval = nla_get_msecs(tb[NDTA_GC_INTERVAL]);
2338
2339 err = 0;
2340
2341errout_tbl_lock:
2342 write_unlock_bh(&tbl->lock);
2343errout:
2344 return err;
2345}
2346
2347static int neightbl_valid_dump_info(const struct nlmsghdr *nlh,
2348 struct netlink_ext_ack *extack)
2349{
2350 struct ndtmsg *ndtm;
2351
2352 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ndtm))) {
2353 NL_SET_ERR_MSG(extack, "Invalid header for neighbor table dump request");
2354 return -EINVAL;
2355 }
2356
2357 ndtm = nlmsg_data(nlh);
2358 if (ndtm->ndtm_pad1 || ndtm->ndtm_pad2) {
2359 NL_SET_ERR_MSG(extack, "Invalid values in header for neighbor table dump request");
2360 return -EINVAL;
2361 }
2362
2363 if (nlmsg_attrlen(nlh, sizeof(*ndtm))) {
2364 NL_SET_ERR_MSG(extack, "Invalid data after header in neighbor table dump request");
2365 return -EINVAL;
2366 }
2367
2368 return 0;
2369}
2370
2371static int neightbl_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
2372{
2373 const struct nlmsghdr *nlh = cb->nlh;
2374 struct net *net = sock_net(skb->sk);
2375 int family, tidx, nidx = 0;
2376 int tbl_skip = cb->args[0];
2377 int neigh_skip = cb->args[1];
2378 struct neigh_table *tbl;
2379
2380 if (cb->strict_check) {
2381 int err = neightbl_valid_dump_info(nlh, cb->extack);
2382
2383 if (err < 0)
2384 return err;
2385 }
2386
2387 family = ((struct rtgenmsg *)nlmsg_data(nlh))->rtgen_family;
2388
2389 for (tidx = 0; tidx < NEIGH_NR_TABLES; tidx++) {
2390 struct neigh_parms *p;
2391
2392 tbl = neigh_tables[tidx];
2393 if (!tbl)
2394 continue;
2395
2396 if (tidx < tbl_skip || (family && tbl->family != family))
2397 continue;
2398
2399 if (neightbl_fill_info(skb, tbl, NETLINK_CB(cb->skb).portid,
2400 nlh->nlmsg_seq, RTM_NEWNEIGHTBL,
2401 NLM_F_MULTI) < 0)
2402 break;
2403
2404 nidx = 0;
2405 p = list_next_entry(&tbl->parms, list);
2406 list_for_each_entry_from(p, &tbl->parms_list, list) {
2407 if (!net_eq(neigh_parms_net(p), net))
2408 continue;
2409
2410 if (nidx < neigh_skip)
2411 goto next;
2412
2413 if (neightbl_fill_param_info(skb, tbl, p,
2414 NETLINK_CB(cb->skb).portid,
2415 nlh->nlmsg_seq,
2416 RTM_NEWNEIGHTBL,
2417 NLM_F_MULTI) < 0)
2418 goto out;
2419 next:
2420 nidx++;
2421 }
2422
2423 neigh_skip = 0;
2424 }
2425out:
2426 cb->args[0] = tidx;
2427 cb->args[1] = nidx;
2428
2429 return skb->len;
2430}
2431
2432static int neigh_fill_info(struct sk_buff *skb, struct neighbour *neigh,
2433 u32 pid, u32 seq, int type, unsigned int flags)
2434{
2435 unsigned long now = jiffies;
2436 struct nda_cacheinfo ci;
2437 struct nlmsghdr *nlh;
2438 struct ndmsg *ndm;
2439
2440 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndm), flags);
2441 if (nlh == NULL)
2442 return -EMSGSIZE;
2443
2444 ndm = nlmsg_data(nlh);
2445 ndm->ndm_family = neigh->ops->family;
2446 ndm->ndm_pad1 = 0;
2447 ndm->ndm_pad2 = 0;
2448 ndm->ndm_flags = neigh->flags;
2449 ndm->ndm_type = neigh->type;
2450 ndm->ndm_ifindex = neigh->dev->ifindex;
2451
2452 if (nla_put(skb, NDA_DST, neigh->tbl->key_len, neigh->primary_key))
2453 goto nla_put_failure;
2454
2455 read_lock_bh(&neigh->lock);
2456 ndm->ndm_state = neigh->nud_state;
2457 if (neigh->nud_state & NUD_VALID) {
2458 char haddr[MAX_ADDR_LEN];
2459
2460 neigh_ha_snapshot(haddr, neigh, neigh->dev);
2461 if (nla_put(skb, NDA_LLADDR, neigh->dev->addr_len, haddr) < 0) {
2462 read_unlock_bh(&neigh->lock);
2463 goto nla_put_failure;
2464 }
2465 }
2466
2467 ci.ndm_used = jiffies_to_clock_t(now - neigh->used);
2468 ci.ndm_confirmed = jiffies_to_clock_t(now - neigh->confirmed);
2469 ci.ndm_updated = jiffies_to_clock_t(now - neigh->updated);
2470 ci.ndm_refcnt = refcount_read(&neigh->refcnt) - 1;
2471 read_unlock_bh(&neigh->lock);
2472
2473 if (nla_put_u32(skb, NDA_PROBES, atomic_read(&neigh->probes)) ||
2474 nla_put(skb, NDA_CACHEINFO, sizeof(ci), &ci))
2475 goto nla_put_failure;
2476
2477 if (neigh->protocol && nla_put_u8(skb, NDA_PROTOCOL, neigh->protocol))
2478 goto nla_put_failure;
2479
2480 nlmsg_end(skb, nlh);
2481 return 0;
2482
2483nla_put_failure:
2484 nlmsg_cancel(skb, nlh);
2485 return -EMSGSIZE;
2486}
2487
2488static int pneigh_fill_info(struct sk_buff *skb, struct pneigh_entry *pn,
2489 u32 pid, u32 seq, int type, unsigned int flags,
2490 struct neigh_table *tbl)
2491{
2492 struct nlmsghdr *nlh;
2493 struct ndmsg *ndm;
2494
2495 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndm), flags);
2496 if (nlh == NULL)
2497 return -EMSGSIZE;
2498
2499 ndm = nlmsg_data(nlh);
2500 ndm->ndm_family = tbl->family;
2501 ndm->ndm_pad1 = 0;
2502 ndm->ndm_pad2 = 0;
2503 ndm->ndm_flags = pn->flags | NTF_PROXY;
2504 ndm->ndm_type = RTN_UNICAST;
2505 ndm->ndm_ifindex = pn->dev ? pn->dev->ifindex : 0;
2506 ndm->ndm_state = NUD_NONE;
2507
2508 if (nla_put(skb, NDA_DST, tbl->key_len, pn->key))
2509 goto nla_put_failure;
2510
2511 if (pn->protocol && nla_put_u8(skb, NDA_PROTOCOL, pn->protocol))
2512 goto nla_put_failure;
2513
2514 nlmsg_end(skb, nlh);
2515 return 0;
2516
2517nla_put_failure:
2518 nlmsg_cancel(skb, nlh);
2519 return -EMSGSIZE;
2520}
2521
2522static void neigh_update_notify(struct neighbour *neigh, u32 nlmsg_pid)
2523{
2524 call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, neigh);
2525 __neigh_notify(neigh, RTM_NEWNEIGH, 0, nlmsg_pid);
2526}
2527
2528static bool neigh_master_filtered(struct net_device *dev, int master_idx)
2529{
2530 struct net_device *master;
2531
2532 if (!master_idx)
2533 return false;
2534
2535 master = dev ? netdev_master_upper_dev_get(dev) : NULL;
2536 if (!master || master->ifindex != master_idx)
2537 return true;
2538
2539 return false;
2540}
2541
2542static bool neigh_ifindex_filtered(struct net_device *dev, int filter_idx)
2543{
2544 if (filter_idx && (!dev || dev->ifindex != filter_idx))
2545 return true;
2546
2547 return false;
2548}
2549
2550struct neigh_dump_filter {
2551 int master_idx;
2552 int dev_idx;
2553};
2554
2555static int neigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb,
2556 struct netlink_callback *cb,
2557 struct neigh_dump_filter *filter)
2558{
2559 struct net *net = sock_net(skb->sk);
2560 struct neighbour *n;
2561 int rc, h, s_h = cb->args[1];
2562 int idx, s_idx = idx = cb->args[2];
2563 struct neigh_hash_table *nht;
2564 unsigned int flags = NLM_F_MULTI;
2565
2566 if (filter->dev_idx || filter->master_idx)
2567 flags |= NLM_F_DUMP_FILTERED;
2568
2569 rcu_read_lock_bh();
2570 nht = rcu_dereference_bh(tbl->nht);
2571
2572 for (h = s_h; h < (1 << nht->hash_shift); h++) {
2573 if (h > s_h)
2574 s_idx = 0;
2575 for (n = rcu_dereference_bh(nht->hash_buckets[h]), idx = 0;
2576 n != NULL;
2577 n = rcu_dereference_bh(n->next)) {
2578 if (idx < s_idx || !net_eq(dev_net(n->dev), net))
2579 goto next;
2580 if (neigh_ifindex_filtered(n->dev, filter->dev_idx) ||
2581 neigh_master_filtered(n->dev, filter->master_idx))
2582 goto next;
2583 if (neigh_fill_info(skb, n, NETLINK_CB(cb->skb).portid,
2584 cb->nlh->nlmsg_seq,
2585 RTM_NEWNEIGH,
2586 flags) < 0) {
2587 rc = -1;
2588 goto out;
2589 }
2590next:
2591 idx++;
2592 }
2593 }
2594 rc = skb->len;
2595out:
2596 rcu_read_unlock_bh();
2597 cb->args[1] = h;
2598 cb->args[2] = idx;
2599 return rc;
2600}
2601
2602static int pneigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb,
2603 struct netlink_callback *cb,
2604 struct neigh_dump_filter *filter)
2605{
2606 struct pneigh_entry *n;
2607 struct net *net = sock_net(skb->sk);
2608 int rc, h, s_h = cb->args[3];
2609 int idx, s_idx = idx = cb->args[4];
2610 unsigned int flags = NLM_F_MULTI;
2611
2612 if (filter->dev_idx || filter->master_idx)
2613 flags |= NLM_F_DUMP_FILTERED;
2614
2615 read_lock_bh(&tbl->lock);
2616
2617 for (h = s_h; h <= PNEIGH_HASHMASK; h++) {
2618 if (h > s_h)
2619 s_idx = 0;
2620 for (n = tbl->phash_buckets[h], idx = 0; n; n = n->next) {
2621 if (idx < s_idx || pneigh_net(n) != net)
2622 goto next;
2623 if (neigh_ifindex_filtered(n->dev, filter->dev_idx) ||
2624 neigh_master_filtered(n->dev, filter->master_idx))
2625 goto next;
2626 if (pneigh_fill_info(skb, n, NETLINK_CB(cb->skb).portid,
2627 cb->nlh->nlmsg_seq,
2628 RTM_NEWNEIGH, flags, tbl) < 0) {
2629 read_unlock_bh(&tbl->lock);
2630 rc = -1;
2631 goto out;
2632 }
2633 next:
2634 idx++;
2635 }
2636 }
2637
2638 read_unlock_bh(&tbl->lock);
2639 rc = skb->len;
2640out:
2641 cb->args[3] = h;
2642 cb->args[4] = idx;
2643 return rc;
2644
2645}
2646
2647static int neigh_valid_dump_req(const struct nlmsghdr *nlh,
2648 bool strict_check,
2649 struct neigh_dump_filter *filter,
2650 struct netlink_ext_ack *extack)
2651{
2652 struct nlattr *tb[NDA_MAX + 1];
2653 int err, i;
2654
2655 if (strict_check) {
2656 struct ndmsg *ndm;
2657
2658 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ndm))) {
2659 NL_SET_ERR_MSG(extack, "Invalid header for neighbor dump request");
2660 return -EINVAL;
2661 }
2662
2663 ndm = nlmsg_data(nlh);
2664 if (ndm->ndm_pad1 || ndm->ndm_pad2 || ndm->ndm_ifindex ||
2665 ndm->ndm_state || ndm->ndm_type) {
2666 NL_SET_ERR_MSG(extack, "Invalid values in header for neighbor dump request");
2667 return -EINVAL;
2668 }
2669
2670 if (ndm->ndm_flags & ~NTF_PROXY) {
2671 NL_SET_ERR_MSG(extack, "Invalid flags in header for neighbor dump request");
2672 return -EINVAL;
2673 }
2674
2675 err = nlmsg_parse_deprecated_strict(nlh, sizeof(struct ndmsg),
2676 tb, NDA_MAX, nda_policy,
2677 extack);
2678 } else {
2679 err = nlmsg_parse_deprecated(nlh, sizeof(struct ndmsg), tb,
2680 NDA_MAX, nda_policy, extack);
2681 }
2682 if (err < 0)
2683 return err;
2684
2685 for (i = 0; i <= NDA_MAX; ++i) {
2686 if (!tb[i])
2687 continue;
2688
2689 /* all new attributes should require strict_check */
2690 switch (i) {
2691 case NDA_IFINDEX:
2692 filter->dev_idx = nla_get_u32(tb[i]);
2693 break;
2694 case NDA_MASTER:
2695 filter->master_idx = nla_get_u32(tb[i]);
2696 break;
2697 default:
2698 if (strict_check) {
2699 NL_SET_ERR_MSG(extack, "Unsupported attribute in neighbor dump request");
2700 return -EINVAL;
2701 }
2702 }
2703 }
2704
2705 return 0;
2706}
2707
2708static int neigh_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
2709{
2710 const struct nlmsghdr *nlh = cb->nlh;
2711 struct neigh_dump_filter filter = {};
2712 struct neigh_table *tbl;
2713 int t, family, s_t;
2714 int proxy = 0;
2715 int err;
2716
2717 family = ((struct rtgenmsg *)nlmsg_data(nlh))->rtgen_family;
2718
2719 /* check for full ndmsg structure presence, family member is
2720 * the same for both structures
2721 */
2722 if (nlmsg_len(nlh) >= sizeof(struct ndmsg) &&
2723 ((struct ndmsg *)nlmsg_data(nlh))->ndm_flags == NTF_PROXY)
2724 proxy = 1;
2725
2726 err = neigh_valid_dump_req(nlh, cb->strict_check, &filter, cb->extack);
2727 if (err < 0 && cb->strict_check)
2728 return err;
2729
2730 s_t = cb->args[0];
2731
2732 for (t = 0; t < NEIGH_NR_TABLES; t++) {
2733 tbl = neigh_tables[t];
2734
2735 if (!tbl)
2736 continue;
2737 if (t < s_t || (family && tbl->family != family))
2738 continue;
2739 if (t > s_t)
2740 memset(&cb->args[1], 0, sizeof(cb->args) -
2741 sizeof(cb->args[0]));
2742 if (proxy)
2743 err = pneigh_dump_table(tbl, skb, cb, &filter);
2744 else
2745 err = neigh_dump_table(tbl, skb, cb, &filter);
2746 if (err < 0)
2747 break;
2748 }
2749
2750 cb->args[0] = t;
2751 return skb->len;
2752}
2753
2754static int neigh_valid_get_req(const struct nlmsghdr *nlh,
2755 struct neigh_table **tbl,
2756 void **dst, int *dev_idx, u8 *ndm_flags,
2757 struct netlink_ext_ack *extack)
2758{
2759 struct nlattr *tb[NDA_MAX + 1];
2760 struct ndmsg *ndm;
2761 int err, i;
2762
2763 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ndm))) {
2764 NL_SET_ERR_MSG(extack, "Invalid header for neighbor get request");
2765 return -EINVAL;
2766 }
2767
2768 ndm = nlmsg_data(nlh);
2769 if (ndm->ndm_pad1 || ndm->ndm_pad2 || ndm->ndm_state ||
2770 ndm->ndm_type) {
2771 NL_SET_ERR_MSG(extack, "Invalid values in header for neighbor get request");
2772 return -EINVAL;
2773 }
2774
2775 if (ndm->ndm_flags & ~NTF_PROXY) {
2776 NL_SET_ERR_MSG(extack, "Invalid flags in header for neighbor get request");
2777 return -EINVAL;
2778 }
2779
2780 err = nlmsg_parse_deprecated_strict(nlh, sizeof(struct ndmsg), tb,
2781 NDA_MAX, nda_policy, extack);
2782 if (err < 0)
2783 return err;
2784
2785 *ndm_flags = ndm->ndm_flags;
2786 *dev_idx = ndm->ndm_ifindex;
2787 *tbl = neigh_find_table(ndm->ndm_family);
2788 if (*tbl == NULL) {
2789 NL_SET_ERR_MSG(extack, "Unsupported family in header for neighbor get request");
2790 return -EAFNOSUPPORT;
2791 }
2792
2793 for (i = 0; i <= NDA_MAX; ++i) {
2794 if (!tb[i])
2795 continue;
2796
2797 switch (i) {
2798 case NDA_DST:
2799 if (nla_len(tb[i]) != (int)(*tbl)->key_len) {
2800 NL_SET_ERR_MSG(extack, "Invalid network address in neighbor get request");
2801 return -EINVAL;
2802 }
2803 *dst = nla_data(tb[i]);
2804 break;
2805 default:
2806 NL_SET_ERR_MSG(extack, "Unsupported attribute in neighbor get request");
2807 return -EINVAL;
2808 }
2809 }
2810
2811 return 0;
2812}
2813
2814static inline size_t neigh_nlmsg_size(void)
2815{
2816 return NLMSG_ALIGN(sizeof(struct ndmsg))
2817 + nla_total_size(MAX_ADDR_LEN) /* NDA_DST */
2818 + nla_total_size(MAX_ADDR_LEN) /* NDA_LLADDR */
2819 + nla_total_size(sizeof(struct nda_cacheinfo))
2820 + nla_total_size(4) /* NDA_PROBES */
2821 + nla_total_size(1); /* NDA_PROTOCOL */
2822}
2823
2824static int neigh_get_reply(struct net *net, struct neighbour *neigh,
2825 u32 pid, u32 seq)
2826{
2827 struct sk_buff *skb;
2828 int err = 0;
2829
2830 skb = nlmsg_new(neigh_nlmsg_size(), GFP_KERNEL);
2831 if (!skb)
2832 return -ENOBUFS;
2833
2834 err = neigh_fill_info(skb, neigh, pid, seq, RTM_NEWNEIGH, 0);
2835 if (err) {
2836 kfree_skb(skb);
2837 goto errout;
2838 }
2839
2840 err = rtnl_unicast(skb, net, pid);
2841errout:
2842 return err;
2843}
2844
2845static inline size_t pneigh_nlmsg_size(void)
2846{
2847 return NLMSG_ALIGN(sizeof(struct ndmsg))
2848 + nla_total_size(MAX_ADDR_LEN) /* NDA_DST */
2849 + nla_total_size(1); /* NDA_PROTOCOL */
2850}
2851
2852static int pneigh_get_reply(struct net *net, struct pneigh_entry *neigh,
2853 u32 pid, u32 seq, struct neigh_table *tbl)
2854{
2855 struct sk_buff *skb;
2856 int err = 0;
2857
2858 skb = nlmsg_new(pneigh_nlmsg_size(), GFP_KERNEL);
2859 if (!skb)
2860 return -ENOBUFS;
2861
2862 err = pneigh_fill_info(skb, neigh, pid, seq, RTM_NEWNEIGH, 0, tbl);
2863 if (err) {
2864 kfree_skb(skb);
2865 goto errout;
2866 }
2867
2868 err = rtnl_unicast(skb, net, pid);
2869errout:
2870 return err;
2871}
2872
2873static int neigh_get(struct sk_buff *in_skb, struct nlmsghdr *nlh,
2874 struct netlink_ext_ack *extack)
2875{
2876 struct net *net = sock_net(in_skb->sk);
2877 struct net_device *dev = NULL;
2878 struct neigh_table *tbl = NULL;
2879 struct neighbour *neigh;
2880 void *dst = NULL;
2881 u8 ndm_flags = 0;
2882 int dev_idx = 0;
2883 int err;
2884
2885 err = neigh_valid_get_req(nlh, &tbl, &dst, &dev_idx, &ndm_flags,
2886 extack);
2887 if (err < 0)
2888 return err;
2889
2890 if (dev_idx) {
2891 dev = __dev_get_by_index(net, dev_idx);
2892 if (!dev) {
2893 NL_SET_ERR_MSG(extack, "Unknown device ifindex");
2894 return -ENODEV;
2895 }
2896 }
2897
2898 if (!dst) {
2899 NL_SET_ERR_MSG(extack, "Network address not specified");
2900 return -EINVAL;
2901 }
2902
2903 if (ndm_flags & NTF_PROXY) {
2904 struct pneigh_entry *pn;
2905
2906 pn = pneigh_lookup(tbl, net, dst, dev, 0);
2907 if (!pn) {
2908 NL_SET_ERR_MSG(extack, "Proxy neighbour entry not found");
2909 return -ENOENT;
2910 }
2911 return pneigh_get_reply(net, pn, NETLINK_CB(in_skb).portid,
2912 nlh->nlmsg_seq, tbl);
2913 }
2914
2915 if (!dev) {
2916 NL_SET_ERR_MSG(extack, "No device specified");
2917 return -EINVAL;
2918 }
2919
2920 neigh = neigh_lookup(tbl, dst, dev);
2921 if (!neigh) {
2922 NL_SET_ERR_MSG(extack, "Neighbour entry not found");
2923 return -ENOENT;
2924 }
2925
2926 err = neigh_get_reply(net, neigh, NETLINK_CB(in_skb).portid,
2927 nlh->nlmsg_seq);
2928
2929 neigh_release(neigh);
2930
2931 return err;
2932}
2933
2934void neigh_for_each(struct neigh_table *tbl, void (*cb)(struct neighbour *, void *), void *cookie)
2935{
2936 int chain;
2937 struct neigh_hash_table *nht;
2938
2939 rcu_read_lock_bh();
2940 nht = rcu_dereference_bh(tbl->nht);
2941
2942 read_lock(&tbl->lock); /* avoid resizes */
2943 for (chain = 0; chain < (1 << nht->hash_shift); chain++) {
2944 struct neighbour *n;
2945
2946 for (n = rcu_dereference_bh(nht->hash_buckets[chain]);
2947 n != NULL;
2948 n = rcu_dereference_bh(n->next))
2949 cb(n, cookie);
2950 }
2951 read_unlock(&tbl->lock);
2952 rcu_read_unlock_bh();
2953}
2954EXPORT_SYMBOL(neigh_for_each);
2955
2956/* The tbl->lock must be held as a writer and BH disabled. */
2957void __neigh_for_each_release(struct neigh_table *tbl,
2958 int (*cb)(struct neighbour *))
2959{
2960 int chain;
2961 struct neigh_hash_table *nht;
2962
2963 nht = rcu_dereference_protected(tbl->nht,
2964 lockdep_is_held(&tbl->lock));
2965 for (chain = 0; chain < (1 << nht->hash_shift); chain++) {
2966 struct neighbour *n;
2967 struct neighbour __rcu **np;
2968
2969 np = &nht->hash_buckets[chain];
2970 while ((n = rcu_dereference_protected(*np,
2971 lockdep_is_held(&tbl->lock))) != NULL) {
2972 int release;
2973
2974 write_lock(&n->lock);
2975 release = cb(n);
2976 if (release) {
2977 rcu_assign_pointer(*np,
2978 rcu_dereference_protected(n->next,
2979 lockdep_is_held(&tbl->lock)));
2980 neigh_mark_dead(n);
2981 } else
2982 np = &n->next;
2983 write_unlock(&n->lock);
2984 if (release)
2985 neigh_cleanup_and_release(n);
2986 }
2987 }
2988}
2989EXPORT_SYMBOL(__neigh_for_each_release);
2990
2991int neigh_xmit(int index, struct net_device *dev,
2992 const void *addr, struct sk_buff *skb)
2993{
2994 int err = -EAFNOSUPPORT;
2995 if (likely(index < NEIGH_NR_TABLES)) {
2996 struct neigh_table *tbl;
2997 struct neighbour *neigh;
2998
2999 tbl = neigh_tables[index];
3000 if (!tbl)
3001 goto out;
3002 rcu_read_lock_bh();
3003 if (index == NEIGH_ARP_TABLE) {
3004 u32 key = *((u32 *)addr);
3005
3006 neigh = __ipv4_neigh_lookup_noref(dev, key);
3007 } else {
3008 neigh = __neigh_lookup_noref(tbl, addr, dev);
3009 }
3010 if (!neigh)
3011 neigh = __neigh_create(tbl, addr, dev, false);
3012 err = PTR_ERR(neigh);
3013 if (IS_ERR(neigh)) {
3014 rcu_read_unlock_bh();
3015 goto out_kfree_skb;
3016 }
3017 err = neigh->output(neigh, skb);
3018 rcu_read_unlock_bh();
3019 }
3020 else if (index == NEIGH_LINK_TABLE) {
3021 err = dev_hard_header(skb, dev, ntohs(skb->protocol),
3022 addr, NULL, skb->len);
3023 if (err < 0)
3024 goto out_kfree_skb;
3025 err = dev_queue_xmit(skb);
3026 }
3027out:
3028 return err;
3029out_kfree_skb:
3030 kfree_skb(skb);
3031 goto out;
3032}
3033EXPORT_SYMBOL(neigh_xmit);
3034
3035#ifdef CONFIG_PROC_FS
3036
3037static struct neighbour *neigh_get_first(struct seq_file *seq)
3038{
3039 struct neigh_seq_state *state = seq->private;
3040 struct net *net = seq_file_net(seq);
3041 struct neigh_hash_table *nht = state->nht;
3042 struct neighbour *n = NULL;
3043 int bucket;
3044
3045 state->flags &= ~NEIGH_SEQ_IS_PNEIGH;
3046 for (bucket = 0; bucket < (1 << nht->hash_shift); bucket++) {
3047 n = rcu_dereference_bh(nht->hash_buckets[bucket]);
3048
3049 while (n) {
3050 if (!net_eq(dev_net(n->dev), net))
3051 goto next;
3052 if (state->neigh_sub_iter) {
3053 loff_t fakep = 0;
3054 void *v;
3055
3056 v = state->neigh_sub_iter(state, n, &fakep);
3057 if (!v)
3058 goto next;
3059 }
3060 if (!(state->flags & NEIGH_SEQ_SKIP_NOARP))
3061 break;
3062 if (n->nud_state & ~NUD_NOARP)
3063 break;
3064next:
3065 n = rcu_dereference_bh(n->next);
3066 }
3067
3068 if (n)
3069 break;
3070 }
3071 state->bucket = bucket;
3072
3073 return n;
3074}
3075
3076static struct neighbour *neigh_get_next(struct seq_file *seq,
3077 struct neighbour *n,
3078 loff_t *pos)
3079{
3080 struct neigh_seq_state *state = seq->private;
3081 struct net *net = seq_file_net(seq);
3082 struct neigh_hash_table *nht = state->nht;
3083
3084 if (state->neigh_sub_iter) {
3085 void *v = state->neigh_sub_iter(state, n, pos);
3086 if (v)
3087 return n;
3088 }
3089 n = rcu_dereference_bh(n->next);
3090
3091 while (1) {
3092 while (n) {
3093 if (!net_eq(dev_net(n->dev), net))
3094 goto next;
3095 if (state->neigh_sub_iter) {
3096 void *v = state->neigh_sub_iter(state, n, pos);
3097 if (v)
3098 return n;
3099 goto next;
3100 }
3101 if (!(state->flags & NEIGH_SEQ_SKIP_NOARP))
3102 break;
3103
3104 if (n->nud_state & ~NUD_NOARP)
3105 break;
3106next:
3107 n = rcu_dereference_bh(n->next);
3108 }
3109
3110 if (n)
3111 break;
3112
3113 if (++state->bucket >= (1 << nht->hash_shift))
3114 break;
3115
3116 n = rcu_dereference_bh(nht->hash_buckets[state->bucket]);
3117 }
3118
3119 if (n && pos)
3120 --(*pos);
3121 return n;
3122}
3123
3124static struct neighbour *neigh_get_idx(struct seq_file *seq, loff_t *pos)
3125{
3126 struct neighbour *n = neigh_get_first(seq);
3127
3128 if (n) {
3129 --(*pos);
3130 while (*pos) {
3131 n = neigh_get_next(seq, n, pos);
3132 if (!n)
3133 break;
3134 }
3135 }
3136 return *pos ? NULL : n;
3137}
3138
3139static struct pneigh_entry *pneigh_get_first(struct seq_file *seq)
3140{
3141 struct neigh_seq_state *state = seq->private;
3142 struct net *net = seq_file_net(seq);
3143 struct neigh_table *tbl = state->tbl;
3144 struct pneigh_entry *pn = NULL;
3145 int bucket;
3146
3147 state->flags |= NEIGH_SEQ_IS_PNEIGH;
3148 for (bucket = 0; bucket <= PNEIGH_HASHMASK; bucket++) {
3149 pn = tbl->phash_buckets[bucket];
3150 while (pn && !net_eq(pneigh_net(pn), net))
3151 pn = pn->next;
3152 if (pn)
3153 break;
3154 }
3155 state->bucket = bucket;
3156
3157 return pn;
3158}
3159
3160static struct pneigh_entry *pneigh_get_next(struct seq_file *seq,
3161 struct pneigh_entry *pn,
3162 loff_t *pos)
3163{
3164 struct neigh_seq_state *state = seq->private;
3165 struct net *net = seq_file_net(seq);
3166 struct neigh_table *tbl = state->tbl;
3167
3168 do {
3169 pn = pn->next;
3170 } while (pn && !net_eq(pneigh_net(pn), net));
3171
3172 while (!pn) {
3173 if (++state->bucket > PNEIGH_HASHMASK)
3174 break;
3175 pn = tbl->phash_buckets[state->bucket];
3176 while (pn && !net_eq(pneigh_net(pn), net))
3177 pn = pn->next;
3178 if (pn)
3179 break;
3180 }
3181
3182 if (pn && pos)
3183 --(*pos);
3184
3185 return pn;
3186}
3187
3188static struct pneigh_entry *pneigh_get_idx(struct seq_file *seq, loff_t *pos)
3189{
3190 struct pneigh_entry *pn = pneigh_get_first(seq);
3191
3192 if (pn) {
3193 --(*pos);
3194 while (*pos) {
3195 pn = pneigh_get_next(seq, pn, pos);
3196 if (!pn)
3197 break;
3198 }
3199 }
3200 return *pos ? NULL : pn;
3201}
3202
3203static void *neigh_get_idx_any(struct seq_file *seq, loff_t *pos)
3204{
3205 struct neigh_seq_state *state = seq->private;
3206 void *rc;
3207 loff_t idxpos = *pos;
3208
3209 rc = neigh_get_idx(seq, &idxpos);
3210 if (!rc && !(state->flags & NEIGH_SEQ_NEIGH_ONLY))
3211 rc = pneigh_get_idx(seq, &idxpos);
3212
3213 return rc;
3214}
3215
3216void *neigh_seq_start(struct seq_file *seq, loff_t *pos, struct neigh_table *tbl, unsigned int neigh_seq_flags)
3217 __acquires(tbl->lock)
3218 __acquires(rcu_bh)
3219{
3220 struct neigh_seq_state *state = seq->private;
3221
3222 state->tbl = tbl;
3223 state->bucket = 0;
3224 state->flags = (neigh_seq_flags & ~NEIGH_SEQ_IS_PNEIGH);
3225
3226 rcu_read_lock_bh();
3227 state->nht = rcu_dereference_bh(tbl->nht);
3228 read_lock(&tbl->lock);
3229
3230 return *pos ? neigh_get_idx_any(seq, pos) : SEQ_START_TOKEN;
3231}
3232EXPORT_SYMBOL(neigh_seq_start);
3233
3234void *neigh_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3235{
3236 struct neigh_seq_state *state;
3237 void *rc;
3238
3239 if (v == SEQ_START_TOKEN) {
3240 rc = neigh_get_first(seq);
3241 goto out;
3242 }
3243
3244 state = seq->private;
3245 if (!(state->flags & NEIGH_SEQ_IS_PNEIGH)) {
3246 rc = neigh_get_next(seq, v, NULL);
3247 if (rc)
3248 goto out;
3249 if (!(state->flags & NEIGH_SEQ_NEIGH_ONLY))
3250 rc = pneigh_get_first(seq);
3251 } else {
3252 BUG_ON(state->flags & NEIGH_SEQ_NEIGH_ONLY);
3253 rc = pneigh_get_next(seq, v, NULL);
3254 }
3255out:
3256 ++(*pos);
3257 return rc;
3258}
3259EXPORT_SYMBOL(neigh_seq_next);
3260
3261void neigh_seq_stop(struct seq_file *seq, void *v)
3262 __releases(tbl->lock)
3263 __releases(rcu_bh)
3264{
3265 struct neigh_seq_state *state = seq->private;
3266 struct neigh_table *tbl = state->tbl;
3267
3268 read_unlock(&tbl->lock);
3269 rcu_read_unlock_bh();
3270}
3271EXPORT_SYMBOL(neigh_seq_stop);
3272
3273/* statistics via seq_file */
3274
3275static void *neigh_stat_seq_start(struct seq_file *seq, loff_t *pos)
3276{
3277 struct neigh_table *tbl = PDE_DATA(file_inode(seq->file));
3278 int cpu;
3279
3280 if (*pos == 0)
3281 return SEQ_START_TOKEN;
3282
3283 for (cpu = *pos-1; cpu < nr_cpu_ids; ++cpu) {
3284 if (!cpu_possible(cpu))
3285 continue;
3286 *pos = cpu+1;
3287 return per_cpu_ptr(tbl->stats, cpu);
3288 }
3289 return NULL;
3290}
3291
3292static void *neigh_stat_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3293{
3294 struct neigh_table *tbl = PDE_DATA(file_inode(seq->file));
3295 int cpu;
3296
3297 for (cpu = *pos; cpu < nr_cpu_ids; ++cpu) {
3298 if (!cpu_possible(cpu))
3299 continue;
3300 *pos = cpu+1;
3301 return per_cpu_ptr(tbl->stats, cpu);
3302 }
3303 (*pos)++;
3304 return NULL;
3305}
3306
3307static void neigh_stat_seq_stop(struct seq_file *seq, void *v)
3308{
3309
3310}
3311
3312static int neigh_stat_seq_show(struct seq_file *seq, void *v)
3313{
3314 struct neigh_table *tbl = PDE_DATA(file_inode(seq->file));
3315 struct neigh_statistics *st = v;
3316
3317 if (v == SEQ_START_TOKEN) {
3318 seq_printf(seq, "entries allocs destroys hash_grows lookups hits res_failed rcv_probes_mcast rcv_probes_ucast periodic_gc_runs forced_gc_runs unresolved_discards table_fulls\n");
3319 return 0;
3320 }
3321
3322 seq_printf(seq, "%08x %08lx %08lx %08lx %08lx %08lx %08lx "
3323 "%08lx %08lx %08lx %08lx %08lx %08lx\n",
3324 atomic_read(&tbl->entries),
3325
3326 st->allocs,
3327 st->destroys,
3328 st->hash_grows,
3329
3330 st->lookups,
3331 st->hits,
3332
3333 st->res_failed,
3334
3335 st->rcv_probes_mcast,
3336 st->rcv_probes_ucast,
3337
3338 st->periodic_gc_runs,
3339 st->forced_gc_runs,
3340 st->unres_discards,
3341 st->table_fulls
3342 );
3343
3344 return 0;
3345}
3346
3347static const struct seq_operations neigh_stat_seq_ops = {
3348 .start = neigh_stat_seq_start,
3349 .next = neigh_stat_seq_next,
3350 .stop = neigh_stat_seq_stop,
3351 .show = neigh_stat_seq_show,
3352};
3353#endif /* CONFIG_PROC_FS */
3354
3355static void __neigh_notify(struct neighbour *n, int type, int flags,
3356 u32 pid)
3357{
3358 struct net *net = dev_net(n->dev);
3359 struct sk_buff *skb;
3360 int err = -ENOBUFS;
3361
3362 skb = nlmsg_new(neigh_nlmsg_size(), GFP_ATOMIC);
3363 if (skb == NULL)
3364 goto errout;
3365
3366 err = neigh_fill_info(skb, n, pid, 0, type, flags);
3367 if (err < 0) {
3368 /* -EMSGSIZE implies BUG in neigh_nlmsg_size() */
3369 WARN_ON(err == -EMSGSIZE);
3370 kfree_skb(skb);
3371 goto errout;
3372 }
3373 rtnl_notify(skb, net, 0, RTNLGRP_NEIGH, NULL, GFP_ATOMIC);
3374 return;
3375errout:
3376 if (err < 0)
3377 rtnl_set_sk_err(net, RTNLGRP_NEIGH, err);
3378}
3379
3380void neigh_app_ns(struct neighbour *n)
3381{
3382 __neigh_notify(n, RTM_GETNEIGH, NLM_F_REQUEST, 0);
3383}
3384EXPORT_SYMBOL(neigh_app_ns);
3385
3386#ifdef CONFIG_SYSCTL
3387static int unres_qlen_max = INT_MAX / SKB_TRUESIZE(ETH_FRAME_LEN);
3388
3389static int proc_unres_qlen(struct ctl_table *ctl, int write,
3390 void *buffer, size_t *lenp, loff_t *ppos)
3391{
3392 int size, ret;
3393 struct ctl_table tmp = *ctl;
3394
3395 tmp.extra1 = SYSCTL_ZERO;
3396 tmp.extra2 = &unres_qlen_max;
3397 tmp.data = &size;
3398
3399 size = *(int *)ctl->data / SKB_TRUESIZE(ETH_FRAME_LEN);
3400 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
3401
3402 if (write && !ret)
3403 *(int *)ctl->data = size * SKB_TRUESIZE(ETH_FRAME_LEN);
3404 return ret;
3405}
3406
3407static struct neigh_parms *neigh_get_dev_parms_rcu(struct net_device *dev,
3408 int family)
3409{
3410 switch (family) {
3411 case AF_INET:
3412 return __in_dev_arp_parms_get_rcu(dev);
3413 case AF_INET6:
3414 return __in6_dev_nd_parms_get_rcu(dev);
3415 }
3416 return NULL;
3417}
3418
3419static void neigh_copy_dflt_parms(struct net *net, struct neigh_parms *p,
3420 int index)
3421{
3422 struct net_device *dev;
3423 int family = neigh_parms_family(p);
3424
3425 rcu_read_lock();
3426 for_each_netdev_rcu(net, dev) {
3427 struct neigh_parms *dst_p =
3428 neigh_get_dev_parms_rcu(dev, family);
3429
3430 if (dst_p && !test_bit(index, dst_p->data_state))
3431 dst_p->data[index] = p->data[index];
3432 }
3433 rcu_read_unlock();
3434}
3435
3436static void neigh_proc_update(struct ctl_table *ctl, int write)
3437{
3438 struct net_device *dev = ctl->extra1;
3439 struct neigh_parms *p = ctl->extra2;
3440 struct net *net = neigh_parms_net(p);
3441 int index = (int *) ctl->data - p->data;
3442
3443 if (!write)
3444 return;
3445
3446 set_bit(index, p->data_state);
3447 if (index == NEIGH_VAR_DELAY_PROBE_TIME)
3448 call_netevent_notifiers(NETEVENT_DELAY_PROBE_TIME_UPDATE, p);
3449 if (!dev) /* NULL dev means this is default value */
3450 neigh_copy_dflt_parms(net, p, index);
3451}
3452
3453static int neigh_proc_dointvec_zero_intmax(struct ctl_table *ctl, int write,
3454 void *buffer, size_t *lenp,
3455 loff_t *ppos)
3456{
3457 struct ctl_table tmp = *ctl;
3458 int ret;
3459
3460 tmp.extra1 = SYSCTL_ZERO;
3461 tmp.extra2 = SYSCTL_INT_MAX;
3462
3463 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
3464 neigh_proc_update(ctl, write);
3465 return ret;
3466}
3467
3468int neigh_proc_dointvec(struct ctl_table *ctl, int write, void *buffer,
3469 size_t *lenp, loff_t *ppos)
3470{
3471 int ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
3472
3473 neigh_proc_update(ctl, write);
3474 return ret;
3475}
3476EXPORT_SYMBOL(neigh_proc_dointvec);
3477
3478int neigh_proc_dointvec_jiffies(struct ctl_table *ctl, int write, void *buffer,
3479 size_t *lenp, loff_t *ppos)
3480{
3481 int ret = proc_dointvec_jiffies(ctl, write, buffer, lenp, ppos);
3482
3483 neigh_proc_update(ctl, write);
3484 return ret;
3485}
3486EXPORT_SYMBOL(neigh_proc_dointvec_jiffies);
3487
3488static int neigh_proc_dointvec_userhz_jiffies(struct ctl_table *ctl, int write,
3489 void *buffer, size_t *lenp,
3490 loff_t *ppos)
3491{
3492 int ret = proc_dointvec_userhz_jiffies(ctl, write, buffer, lenp, ppos);
3493
3494 neigh_proc_update(ctl, write);
3495 return ret;
3496}
3497
3498int neigh_proc_dointvec_ms_jiffies(struct ctl_table *ctl, int write,
3499 void *buffer, size_t *lenp, loff_t *ppos)
3500{
3501 int ret = proc_dointvec_ms_jiffies(ctl, write, buffer, lenp, ppos);
3502
3503 neigh_proc_update(ctl, write);
3504 return ret;
3505}
3506EXPORT_SYMBOL(neigh_proc_dointvec_ms_jiffies);
3507
3508static int neigh_proc_dointvec_unres_qlen(struct ctl_table *ctl, int write,
3509 void *buffer, size_t *lenp,
3510 loff_t *ppos)
3511{
3512 int ret = proc_unres_qlen(ctl, write, buffer, lenp, ppos);
3513
3514 neigh_proc_update(ctl, write);
3515 return ret;
3516}
3517
3518static int neigh_proc_base_reachable_time(struct ctl_table *ctl, int write,
3519 void *buffer, size_t *lenp,
3520 loff_t *ppos)
3521{
3522 struct neigh_parms *p = ctl->extra2;
3523 int ret;
3524
3525 if (strcmp(ctl->procname, "base_reachable_time") == 0)
3526 ret = neigh_proc_dointvec_jiffies(ctl, write, buffer, lenp, ppos);
3527 else if (strcmp(ctl->procname, "base_reachable_time_ms") == 0)
3528 ret = neigh_proc_dointvec_ms_jiffies(ctl, write, buffer, lenp, ppos);
3529 else
3530 ret = -1;
3531
3532 if (write && ret == 0) {
3533 /* update reachable_time as well, otherwise, the change will
3534 * only be effective after the next time neigh_periodic_work
3535 * decides to recompute it
3536 */
3537 p->reachable_time =
3538 neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME));
3539 }
3540 return ret;
3541}
3542
3543#define NEIGH_PARMS_DATA_OFFSET(index) \
3544 (&((struct neigh_parms *) 0)->data[index])
3545
3546#define NEIGH_SYSCTL_ENTRY(attr, data_attr, name, mval, proc) \
3547 [NEIGH_VAR_ ## attr] = { \
3548 .procname = name, \
3549 .data = NEIGH_PARMS_DATA_OFFSET(NEIGH_VAR_ ## data_attr), \
3550 .maxlen = sizeof(int), \
3551 .mode = mval, \
3552 .proc_handler = proc, \
3553 }
3554
3555#define NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(attr, name) \
3556 NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_zero_intmax)
3557
3558#define NEIGH_SYSCTL_JIFFIES_ENTRY(attr, name) \
3559 NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_jiffies)
3560
3561#define NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(attr, name) \
3562 NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_userhz_jiffies)
3563
3564#define NEIGH_SYSCTL_MS_JIFFIES_REUSED_ENTRY(attr, data_attr, name) \
3565 NEIGH_SYSCTL_ENTRY(attr, data_attr, name, 0644, neigh_proc_dointvec_ms_jiffies)
3566
3567#define NEIGH_SYSCTL_UNRES_QLEN_REUSED_ENTRY(attr, data_attr, name) \
3568 NEIGH_SYSCTL_ENTRY(attr, data_attr, name, 0644, neigh_proc_dointvec_unres_qlen)
3569
3570static struct neigh_sysctl_table {
3571 struct ctl_table_header *sysctl_header;
3572 struct ctl_table neigh_vars[NEIGH_VAR_MAX + 1];
3573} neigh_sysctl_template __read_mostly = {
3574 .neigh_vars = {
3575 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(MCAST_PROBES, "mcast_solicit"),
3576 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(UCAST_PROBES, "ucast_solicit"),
3577 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(APP_PROBES, "app_solicit"),
3578 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(MCAST_REPROBES, "mcast_resolicit"),
3579 NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(RETRANS_TIME, "retrans_time"),
3580 NEIGH_SYSCTL_JIFFIES_ENTRY(BASE_REACHABLE_TIME, "base_reachable_time"),
3581 NEIGH_SYSCTL_JIFFIES_ENTRY(DELAY_PROBE_TIME, "delay_first_probe_time"),
3582 NEIGH_SYSCTL_JIFFIES_ENTRY(GC_STALETIME, "gc_stale_time"),
3583 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(QUEUE_LEN_BYTES, "unres_qlen_bytes"),
3584 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(PROXY_QLEN, "proxy_qlen"),
3585 NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(ANYCAST_DELAY, "anycast_delay"),
3586 NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(PROXY_DELAY, "proxy_delay"),
3587 NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(LOCKTIME, "locktime"),
3588 NEIGH_SYSCTL_UNRES_QLEN_REUSED_ENTRY(QUEUE_LEN, QUEUE_LEN_BYTES, "unres_qlen"),
3589 NEIGH_SYSCTL_MS_JIFFIES_REUSED_ENTRY(RETRANS_TIME_MS, RETRANS_TIME, "retrans_time_ms"),
3590 NEIGH_SYSCTL_MS_JIFFIES_REUSED_ENTRY(BASE_REACHABLE_TIME_MS, BASE_REACHABLE_TIME, "base_reachable_time_ms"),
3591 [NEIGH_VAR_GC_INTERVAL] = {
3592 .procname = "gc_interval",
3593 .maxlen = sizeof(int),
3594 .mode = 0644,
3595 .proc_handler = proc_dointvec_jiffies,
3596 },
3597 [NEIGH_VAR_GC_THRESH1] = {
3598 .procname = "gc_thresh1",
3599 .maxlen = sizeof(int),
3600 .mode = 0644,
3601 .extra1 = SYSCTL_ZERO,
3602 .extra2 = SYSCTL_INT_MAX,
3603 .proc_handler = proc_dointvec_minmax,
3604 },
3605 [NEIGH_VAR_GC_THRESH2] = {
3606 .procname = "gc_thresh2",
3607 .maxlen = sizeof(int),
3608 .mode = 0644,
3609 .extra1 = SYSCTL_ZERO,
3610 .extra2 = SYSCTL_INT_MAX,
3611 .proc_handler = proc_dointvec_minmax,
3612 },
3613 [NEIGH_VAR_GC_THRESH3] = {
3614 .procname = "gc_thresh3",
3615 .maxlen = sizeof(int),
3616 .mode = 0644,
3617 .extra1 = SYSCTL_ZERO,
3618 .extra2 = SYSCTL_INT_MAX,
3619 .proc_handler = proc_dointvec_minmax,
3620 },
3621 {},
3622 },
3623};
3624
3625int neigh_sysctl_register(struct net_device *dev, struct neigh_parms *p,
3626 proc_handler *handler)
3627{
3628 int i;
3629 struct neigh_sysctl_table *t;
3630 const char *dev_name_source;
3631 char neigh_path[ sizeof("net//neigh/") + IFNAMSIZ + IFNAMSIZ ];
3632 char *p_name;
3633
3634 t = kmemdup(&neigh_sysctl_template, sizeof(*t), GFP_KERNEL);
3635 if (!t)
3636 goto err;
3637
3638 for (i = 0; i < NEIGH_VAR_GC_INTERVAL; i++) {
3639 t->neigh_vars[i].data += (long) p;
3640 t->neigh_vars[i].extra1 = dev;
3641 t->neigh_vars[i].extra2 = p;
3642 }
3643
3644 if (dev) {
3645 dev_name_source = dev->name;
3646 /* Terminate the table early */
3647 memset(&t->neigh_vars[NEIGH_VAR_GC_INTERVAL], 0,
3648 sizeof(t->neigh_vars[NEIGH_VAR_GC_INTERVAL]));
3649 } else {
3650 struct neigh_table *tbl = p->tbl;
3651 dev_name_source = "default";
3652 t->neigh_vars[NEIGH_VAR_GC_INTERVAL].data = &tbl->gc_interval;
3653 t->neigh_vars[NEIGH_VAR_GC_THRESH1].data = &tbl->gc_thresh1;
3654 t->neigh_vars[NEIGH_VAR_GC_THRESH2].data = &tbl->gc_thresh2;
3655 t->neigh_vars[NEIGH_VAR_GC_THRESH3].data = &tbl->gc_thresh3;
3656 }
3657
3658 if (handler) {
3659 /* RetransTime */
3660 t->neigh_vars[NEIGH_VAR_RETRANS_TIME].proc_handler = handler;
3661 /* ReachableTime */
3662 t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME].proc_handler = handler;
3663 /* RetransTime (in milliseconds)*/
3664 t->neigh_vars[NEIGH_VAR_RETRANS_TIME_MS].proc_handler = handler;
3665 /* ReachableTime (in milliseconds) */
3666 t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME_MS].proc_handler = handler;
3667 } else {
3668 /* Those handlers will update p->reachable_time after
3669 * base_reachable_time(_ms) is set to ensure the new timer starts being
3670 * applied after the next neighbour update instead of waiting for
3671 * neigh_periodic_work to update its value (can be multiple minutes)
3672 * So any handler that replaces them should do this as well
3673 */
3674 /* ReachableTime */
3675 t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME].proc_handler =
3676 neigh_proc_base_reachable_time;
3677 /* ReachableTime (in milliseconds) */
3678 t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME_MS].proc_handler =
3679 neigh_proc_base_reachable_time;
3680 }
3681
3682 /* Don't export sysctls to unprivileged users */
3683 if (neigh_parms_net(p)->user_ns != &init_user_ns)
3684 t->neigh_vars[0].procname = NULL;
3685
3686 switch (neigh_parms_family(p)) {
3687 case AF_INET:
3688 p_name = "ipv4";
3689 break;
3690 case AF_INET6:
3691 p_name = "ipv6";
3692 break;
3693 default:
3694 BUG();
3695 }
3696
3697 snprintf(neigh_path, sizeof(neigh_path), "net/%s/neigh/%s",
3698 p_name, dev_name_source);
3699 t->sysctl_header =
3700 register_net_sysctl(neigh_parms_net(p), neigh_path, t->neigh_vars);
3701 if (!t->sysctl_header)
3702 goto free;
3703
3704 p->sysctl_table = t;
3705 return 0;
3706
3707free:
3708 kfree(t);
3709err:
3710 return -ENOBUFS;
3711}
3712EXPORT_SYMBOL(neigh_sysctl_register);
3713
3714void neigh_sysctl_unregister(struct neigh_parms *p)
3715{
3716 if (p->sysctl_table) {
3717 struct neigh_sysctl_table *t = p->sysctl_table;
3718 p->sysctl_table = NULL;
3719 unregister_net_sysctl_table(t->sysctl_header);
3720 kfree(t);
3721 }
3722}
3723EXPORT_SYMBOL(neigh_sysctl_unregister);
3724
3725#endif /* CONFIG_SYSCTL */
3726
3727static int __init neigh_init(void)
3728{
3729 rtnl_register(PF_UNSPEC, RTM_NEWNEIGH, neigh_add, NULL, 0);
3730 rtnl_register(PF_UNSPEC, RTM_DELNEIGH, neigh_delete, NULL, 0);
3731 rtnl_register(PF_UNSPEC, RTM_GETNEIGH, neigh_get, neigh_dump_info, 0);
3732
3733 rtnl_register(PF_UNSPEC, RTM_GETNEIGHTBL, NULL, neightbl_dump_info,
3734 0);
3735 rtnl_register(PF_UNSPEC, RTM_SETNEIGHTBL, neightbl_set, NULL, 0);
3736
3737 return 0;
3738}
3739
3740subsys_initcall(neigh_init);