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