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1/*
2 * Generic address resolution entity
3 *
4 * Authors:
5 * Pedro Roque <roque@di.fc.ul.pt>
6 * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License
10 * as published by the Free Software Foundation; either version
11 * 2 of the License, or (at your option) any later version.
12 *
13 * Fixes:
14 * Vitaly E. Lavrov releasing NULL neighbor in neigh_add.
15 * Harald Welte Add neighbour cache statistics like rtstat
16 */
17
18#include <linux/slab.h>
19#include <linux/types.h>
20#include <linux/kernel.h>
21#include <linux/module.h>
22#include <linux/socket.h>
23#include <linux/netdevice.h>
24#include <linux/proc_fs.h>
25#ifdef CONFIG_SYSCTL
26#include <linux/sysctl.h>
27#endif
28#include <linux/times.h>
29#include <net/net_namespace.h>
30#include <net/neighbour.h>
31#include <net/dst.h>
32#include <net/sock.h>
33#include <net/netevent.h>
34#include <net/netlink.h>
35#include <linux/rtnetlink.h>
36#include <linux/random.h>
37#include <linux/string.h>
38#include <linux/log2.h>
39
40#define NEIGH_DEBUG 1
41
42#define NEIGH_PRINTK(x...) printk(x)
43#define NEIGH_NOPRINTK(x...) do { ; } while(0)
44#define NEIGH_PRINTK1 NEIGH_NOPRINTK
45#define NEIGH_PRINTK2 NEIGH_NOPRINTK
46
47#if NEIGH_DEBUG >= 1
48#undef NEIGH_PRINTK1
49#define NEIGH_PRINTK1 NEIGH_PRINTK
50#endif
51#if NEIGH_DEBUG >= 2
52#undef NEIGH_PRINTK2
53#define NEIGH_PRINTK2 NEIGH_PRINTK
54#endif
55
56#define PNEIGH_HASHMASK 0xF
57
58static void neigh_timer_handler(unsigned long arg);
59static void __neigh_notify(struct neighbour *n, int type, int flags);
60static void neigh_update_notify(struct neighbour *neigh);
61static int pneigh_ifdown(struct neigh_table *tbl, struct net_device *dev);
62
63static struct neigh_table *neigh_tables;
64#ifdef CONFIG_PROC_FS
65static const struct file_operations neigh_stat_seq_fops;
66#endif
67
68/*
69 Neighbour hash table buckets are protected with rwlock tbl->lock.
70
71 - All the scans/updates to hash buckets MUST be made under this lock.
72 - NOTHING clever should be made under this lock: no callbacks
73 to protocol backends, no attempts to send something to network.
74 It will result in deadlocks, if backend/driver wants to use neighbour
75 cache.
76 - If the entry requires some non-trivial actions, increase
77 its reference count and release table lock.
78
79 Neighbour entries are protected:
80 - with reference count.
81 - with rwlock neigh->lock
82
83 Reference count prevents destruction.
84
85 neigh->lock mainly serializes ll address data and its validity state.
86 However, the same lock is used to protect another entry fields:
87 - timer
88 - resolution queue
89
90 Again, nothing clever shall be made under neigh->lock,
91 the most complicated procedure, which we allow is dev->hard_header.
92 It is supposed, that dev->hard_header is simplistic and does
93 not make callbacks to neighbour tables.
94
95 The last lock is neigh_tbl_lock. It is pure SMP lock, protecting
96 list of neighbour tables. This list is used only in process context,
97 */
98
99static DEFINE_RWLOCK(neigh_tbl_lock);
100
101static int neigh_blackhole(struct neighbour *neigh, struct sk_buff *skb)
102{
103 kfree_skb(skb);
104 return -ENETDOWN;
105}
106
107static void neigh_cleanup_and_release(struct neighbour *neigh)
108{
109 if (neigh->parms->neigh_cleanup)
110 neigh->parms->neigh_cleanup(neigh);
111
112 __neigh_notify(neigh, RTM_DELNEIGH, 0);
113 neigh_release(neigh);
114}
115
116/*
117 * It is random distribution in the interval (1/2)*base...(3/2)*base.
118 * It corresponds to default IPv6 settings and is not overridable,
119 * because it is really reasonable choice.
120 */
121
122unsigned long neigh_rand_reach_time(unsigned long base)
123{
124 return base ? (net_random() % base) + (base >> 1) : 0;
125}
126EXPORT_SYMBOL(neigh_rand_reach_time);
127
128
129static int neigh_forced_gc(struct neigh_table *tbl)
130{
131 int shrunk = 0;
132 int i;
133 struct neigh_hash_table *nht;
134
135 NEIGH_CACHE_STAT_INC(tbl, forced_gc_runs);
136
137 write_lock_bh(&tbl->lock);
138 nht = rcu_dereference_protected(tbl->nht,
139 lockdep_is_held(&tbl->lock));
140 for (i = 0; i < (1 << nht->hash_shift); i++) {
141 struct neighbour *n;
142 struct neighbour __rcu **np;
143
144 np = &nht->hash_buckets[i];
145 while ((n = rcu_dereference_protected(*np,
146 lockdep_is_held(&tbl->lock))) != NULL) {
147 /* Neighbour record may be discarded if:
148 * - nobody refers to it.
149 * - it is not permanent
150 */
151 write_lock(&n->lock);
152 if (atomic_read(&n->refcnt) == 1 &&
153 !(n->nud_state & NUD_PERMANENT)) {
154 rcu_assign_pointer(*np,
155 rcu_dereference_protected(n->next,
156 lockdep_is_held(&tbl->lock)));
157 n->dead = 1;
158 shrunk = 1;
159 write_unlock(&n->lock);
160 neigh_cleanup_and_release(n);
161 continue;
162 }
163 write_unlock(&n->lock);
164 np = &n->next;
165 }
166 }
167
168 tbl->last_flush = jiffies;
169
170 write_unlock_bh(&tbl->lock);
171
172 return shrunk;
173}
174
175static void neigh_add_timer(struct neighbour *n, unsigned long when)
176{
177 neigh_hold(n);
178 if (unlikely(mod_timer(&n->timer, when))) {
179 printk("NEIGH: BUG, double timer add, state is %x\n",
180 n->nud_state);
181 dump_stack();
182 }
183}
184
185static int neigh_del_timer(struct neighbour *n)
186{
187 if ((n->nud_state & NUD_IN_TIMER) &&
188 del_timer(&n->timer)) {
189 neigh_release(n);
190 return 1;
191 }
192 return 0;
193}
194
195static void pneigh_queue_purge(struct sk_buff_head *list)
196{
197 struct sk_buff *skb;
198
199 while ((skb = skb_dequeue(list)) != NULL) {
200 dev_put(skb->dev);
201 kfree_skb(skb);
202 }
203}
204
205static void neigh_flush_dev(struct neigh_table *tbl, struct net_device *dev)
206{
207 int i;
208 struct neigh_hash_table *nht;
209
210 nht = rcu_dereference_protected(tbl->nht,
211 lockdep_is_held(&tbl->lock));
212
213 for (i = 0; i < (1 << nht->hash_shift); i++) {
214 struct neighbour *n;
215 struct neighbour __rcu **np = &nht->hash_buckets[i];
216
217 while ((n = rcu_dereference_protected(*np,
218 lockdep_is_held(&tbl->lock))) != NULL) {
219 if (dev && n->dev != dev) {
220 np = &n->next;
221 continue;
222 }
223 rcu_assign_pointer(*np,
224 rcu_dereference_protected(n->next,
225 lockdep_is_held(&tbl->lock)));
226 write_lock(&n->lock);
227 neigh_del_timer(n);
228 n->dead = 1;
229
230 if (atomic_read(&n->refcnt) != 1) {
231 /* The most unpleasant situation.
232 We must destroy neighbour entry,
233 but someone still uses it.
234
235 The destroy will be delayed until
236 the last user releases us, but
237 we must kill timers etc. and move
238 it to safe state.
239 */
240 skb_queue_purge(&n->arp_queue);
241 n->output = neigh_blackhole;
242 if (n->nud_state & NUD_VALID)
243 n->nud_state = NUD_NOARP;
244 else
245 n->nud_state = NUD_NONE;
246 NEIGH_PRINTK2("neigh %p is stray.\n", n);
247 }
248 write_unlock(&n->lock);
249 neigh_cleanup_and_release(n);
250 }
251 }
252}
253
254void neigh_changeaddr(struct neigh_table *tbl, struct net_device *dev)
255{
256 write_lock_bh(&tbl->lock);
257 neigh_flush_dev(tbl, dev);
258 write_unlock_bh(&tbl->lock);
259}
260EXPORT_SYMBOL(neigh_changeaddr);
261
262int neigh_ifdown(struct neigh_table *tbl, struct net_device *dev)
263{
264 write_lock_bh(&tbl->lock);
265 neigh_flush_dev(tbl, dev);
266 pneigh_ifdown(tbl, dev);
267 write_unlock_bh(&tbl->lock);
268
269 del_timer_sync(&tbl->proxy_timer);
270 pneigh_queue_purge(&tbl->proxy_queue);
271 return 0;
272}
273EXPORT_SYMBOL(neigh_ifdown);
274
275static struct neighbour *neigh_alloc(struct neigh_table *tbl)
276{
277 struct neighbour *n = NULL;
278 unsigned long now = jiffies;
279 int entries;
280
281 entries = atomic_inc_return(&tbl->entries) - 1;
282 if (entries >= tbl->gc_thresh3 ||
283 (entries >= tbl->gc_thresh2 &&
284 time_after(now, tbl->last_flush + 5 * HZ))) {
285 if (!neigh_forced_gc(tbl) &&
286 entries >= tbl->gc_thresh3)
287 goto out_entries;
288 }
289
290 n = kmem_cache_zalloc(tbl->kmem_cachep, GFP_ATOMIC);
291 if (!n)
292 goto out_entries;
293
294 skb_queue_head_init(&n->arp_queue);
295 rwlock_init(&n->lock);
296 seqlock_init(&n->ha_lock);
297 n->updated = n->used = now;
298 n->nud_state = NUD_NONE;
299 n->output = neigh_blackhole;
300 seqlock_init(&n->hh.hh_lock);
301 n->parms = neigh_parms_clone(&tbl->parms);
302 setup_timer(&n->timer, neigh_timer_handler, (unsigned long)n);
303
304 NEIGH_CACHE_STAT_INC(tbl, allocs);
305 n->tbl = tbl;
306 atomic_set(&n->refcnt, 1);
307 n->dead = 1;
308out:
309 return n;
310
311out_entries:
312 atomic_dec(&tbl->entries);
313 goto out;
314}
315
316static struct neigh_hash_table *neigh_hash_alloc(unsigned int shift)
317{
318 size_t size = (1 << shift) * sizeof(struct neighbour *);
319 struct neigh_hash_table *ret;
320 struct neighbour __rcu **buckets;
321
322 ret = kmalloc(sizeof(*ret), GFP_ATOMIC);
323 if (!ret)
324 return NULL;
325 if (size <= PAGE_SIZE)
326 buckets = kzalloc(size, GFP_ATOMIC);
327 else
328 buckets = (struct neighbour __rcu **)
329 __get_free_pages(GFP_ATOMIC | __GFP_ZERO,
330 get_order(size));
331 if (!buckets) {
332 kfree(ret);
333 return NULL;
334 }
335 ret->hash_buckets = buckets;
336 ret->hash_shift = shift;
337 get_random_bytes(&ret->hash_rnd, sizeof(ret->hash_rnd));
338 ret->hash_rnd |= 1;
339 return ret;
340}
341
342static void neigh_hash_free_rcu(struct rcu_head *head)
343{
344 struct neigh_hash_table *nht = container_of(head,
345 struct neigh_hash_table,
346 rcu);
347 size_t size = (1 << nht->hash_shift) * sizeof(struct neighbour *);
348 struct neighbour __rcu **buckets = nht->hash_buckets;
349
350 if (size <= PAGE_SIZE)
351 kfree(buckets);
352 else
353 free_pages((unsigned long)buckets, get_order(size));
354 kfree(nht);
355}
356
357static struct neigh_hash_table *neigh_hash_grow(struct neigh_table *tbl,
358 unsigned long new_shift)
359{
360 unsigned int i, hash;
361 struct neigh_hash_table *new_nht, *old_nht;
362
363 NEIGH_CACHE_STAT_INC(tbl, hash_grows);
364
365 old_nht = rcu_dereference_protected(tbl->nht,
366 lockdep_is_held(&tbl->lock));
367 new_nht = neigh_hash_alloc(new_shift);
368 if (!new_nht)
369 return old_nht;
370
371 for (i = 0; i < (1 << old_nht->hash_shift); i++) {
372 struct neighbour *n, *next;
373
374 for (n = rcu_dereference_protected(old_nht->hash_buckets[i],
375 lockdep_is_held(&tbl->lock));
376 n != NULL;
377 n = next) {
378 hash = tbl->hash(n->primary_key, n->dev,
379 new_nht->hash_rnd);
380
381 hash >>= (32 - new_nht->hash_shift);
382 next = rcu_dereference_protected(n->next,
383 lockdep_is_held(&tbl->lock));
384
385 rcu_assign_pointer(n->next,
386 rcu_dereference_protected(
387 new_nht->hash_buckets[hash],
388 lockdep_is_held(&tbl->lock)));
389 rcu_assign_pointer(new_nht->hash_buckets[hash], n);
390 }
391 }
392
393 rcu_assign_pointer(tbl->nht, new_nht);
394 call_rcu(&old_nht->rcu, neigh_hash_free_rcu);
395 return new_nht;
396}
397
398struct neighbour *neigh_lookup(struct neigh_table *tbl, const void *pkey,
399 struct net_device *dev)
400{
401 struct neighbour *n;
402 int key_len = tbl->key_len;
403 u32 hash_val;
404 struct neigh_hash_table *nht;
405
406 NEIGH_CACHE_STAT_INC(tbl, lookups);
407
408 rcu_read_lock_bh();
409 nht = rcu_dereference_bh(tbl->nht);
410 hash_val = tbl->hash(pkey, dev, nht->hash_rnd) >> (32 - nht->hash_shift);
411
412 for (n = rcu_dereference_bh(nht->hash_buckets[hash_val]);
413 n != NULL;
414 n = rcu_dereference_bh(n->next)) {
415 if (dev == n->dev && !memcmp(n->primary_key, pkey, key_len)) {
416 if (!atomic_inc_not_zero(&n->refcnt))
417 n = NULL;
418 NEIGH_CACHE_STAT_INC(tbl, hits);
419 break;
420 }
421 }
422
423 rcu_read_unlock_bh();
424 return n;
425}
426EXPORT_SYMBOL(neigh_lookup);
427
428struct neighbour *neigh_lookup_nodev(struct neigh_table *tbl, struct net *net,
429 const void *pkey)
430{
431 struct neighbour *n;
432 int key_len = tbl->key_len;
433 u32 hash_val;
434 struct neigh_hash_table *nht;
435
436 NEIGH_CACHE_STAT_INC(tbl, lookups);
437
438 rcu_read_lock_bh();
439 nht = rcu_dereference_bh(tbl->nht);
440 hash_val = tbl->hash(pkey, NULL, nht->hash_rnd) >> (32 - nht->hash_shift);
441
442 for (n = rcu_dereference_bh(nht->hash_buckets[hash_val]);
443 n != NULL;
444 n = rcu_dereference_bh(n->next)) {
445 if (!memcmp(n->primary_key, pkey, key_len) &&
446 net_eq(dev_net(n->dev), net)) {
447 if (!atomic_inc_not_zero(&n->refcnt))
448 n = NULL;
449 NEIGH_CACHE_STAT_INC(tbl, hits);
450 break;
451 }
452 }
453
454 rcu_read_unlock_bh();
455 return n;
456}
457EXPORT_SYMBOL(neigh_lookup_nodev);
458
459struct neighbour *neigh_create(struct neigh_table *tbl, const void *pkey,
460 struct net_device *dev)
461{
462 u32 hash_val;
463 int key_len = tbl->key_len;
464 int error;
465 struct neighbour *n1, *rc, *n = neigh_alloc(tbl);
466 struct neigh_hash_table *nht;
467
468 if (!n) {
469 rc = ERR_PTR(-ENOBUFS);
470 goto out;
471 }
472
473 memcpy(n->primary_key, pkey, key_len);
474 n->dev = dev;
475 dev_hold(dev);
476
477 /* Protocol specific setup. */
478 if (tbl->constructor && (error = tbl->constructor(n)) < 0) {
479 rc = ERR_PTR(error);
480 goto out_neigh_release;
481 }
482
483 /* Device specific setup. */
484 if (n->parms->neigh_setup &&
485 (error = n->parms->neigh_setup(n)) < 0) {
486 rc = ERR_PTR(error);
487 goto out_neigh_release;
488 }
489
490 n->confirmed = jiffies - (n->parms->base_reachable_time << 1);
491
492 write_lock_bh(&tbl->lock);
493 nht = rcu_dereference_protected(tbl->nht,
494 lockdep_is_held(&tbl->lock));
495
496 if (atomic_read(&tbl->entries) > (1 << nht->hash_shift))
497 nht = neigh_hash_grow(tbl, nht->hash_shift + 1);
498
499 hash_val = tbl->hash(pkey, dev, nht->hash_rnd) >> (32 - nht->hash_shift);
500
501 if (n->parms->dead) {
502 rc = ERR_PTR(-EINVAL);
503 goto out_tbl_unlock;
504 }
505
506 for (n1 = rcu_dereference_protected(nht->hash_buckets[hash_val],
507 lockdep_is_held(&tbl->lock));
508 n1 != NULL;
509 n1 = rcu_dereference_protected(n1->next,
510 lockdep_is_held(&tbl->lock))) {
511 if (dev == n1->dev && !memcmp(n1->primary_key, pkey, key_len)) {
512 neigh_hold(n1);
513 rc = n1;
514 goto out_tbl_unlock;
515 }
516 }
517
518 n->dead = 0;
519 neigh_hold(n);
520 rcu_assign_pointer(n->next,
521 rcu_dereference_protected(nht->hash_buckets[hash_val],
522 lockdep_is_held(&tbl->lock)));
523 rcu_assign_pointer(nht->hash_buckets[hash_val], n);
524 write_unlock_bh(&tbl->lock);
525 NEIGH_PRINTK2("neigh %p is created.\n", n);
526 rc = n;
527out:
528 return rc;
529out_tbl_unlock:
530 write_unlock_bh(&tbl->lock);
531out_neigh_release:
532 neigh_release(n);
533 goto out;
534}
535EXPORT_SYMBOL(neigh_create);
536
537static u32 pneigh_hash(const void *pkey, int key_len)
538{
539 u32 hash_val = *(u32 *)(pkey + key_len - 4);
540 hash_val ^= (hash_val >> 16);
541 hash_val ^= hash_val >> 8;
542 hash_val ^= hash_val >> 4;
543 hash_val &= PNEIGH_HASHMASK;
544 return hash_val;
545}
546
547static struct pneigh_entry *__pneigh_lookup_1(struct pneigh_entry *n,
548 struct net *net,
549 const void *pkey,
550 int key_len,
551 struct net_device *dev)
552{
553 while (n) {
554 if (!memcmp(n->key, pkey, key_len) &&
555 net_eq(pneigh_net(n), net) &&
556 (n->dev == dev || !n->dev))
557 return n;
558 n = n->next;
559 }
560 return NULL;
561}
562
563struct pneigh_entry *__pneigh_lookup(struct neigh_table *tbl,
564 struct net *net, const void *pkey, struct net_device *dev)
565{
566 int key_len = tbl->key_len;
567 u32 hash_val = pneigh_hash(pkey, key_len);
568
569 return __pneigh_lookup_1(tbl->phash_buckets[hash_val],
570 net, pkey, key_len, dev);
571}
572EXPORT_SYMBOL_GPL(__pneigh_lookup);
573
574struct pneigh_entry * pneigh_lookup(struct neigh_table *tbl,
575 struct net *net, const void *pkey,
576 struct net_device *dev, int creat)
577{
578 struct pneigh_entry *n;
579 int key_len = tbl->key_len;
580 u32 hash_val = pneigh_hash(pkey, key_len);
581
582 read_lock_bh(&tbl->lock);
583 n = __pneigh_lookup_1(tbl->phash_buckets[hash_val],
584 net, pkey, key_len, dev);
585 read_unlock_bh(&tbl->lock);
586
587 if (n || !creat)
588 goto out;
589
590 ASSERT_RTNL();
591
592 n = kmalloc(sizeof(*n) + key_len, GFP_KERNEL);
593 if (!n)
594 goto out;
595
596 write_pnet(&n->net, hold_net(net));
597 memcpy(n->key, pkey, key_len);
598 n->dev = dev;
599 if (dev)
600 dev_hold(dev);
601
602 if (tbl->pconstructor && tbl->pconstructor(n)) {
603 if (dev)
604 dev_put(dev);
605 release_net(net);
606 kfree(n);
607 n = NULL;
608 goto out;
609 }
610
611 write_lock_bh(&tbl->lock);
612 n->next = tbl->phash_buckets[hash_val];
613 tbl->phash_buckets[hash_val] = n;
614 write_unlock_bh(&tbl->lock);
615out:
616 return n;
617}
618EXPORT_SYMBOL(pneigh_lookup);
619
620
621int pneigh_delete(struct neigh_table *tbl, struct net *net, const void *pkey,
622 struct net_device *dev)
623{
624 struct pneigh_entry *n, **np;
625 int key_len = tbl->key_len;
626 u32 hash_val = pneigh_hash(pkey, key_len);
627
628 write_lock_bh(&tbl->lock);
629 for (np = &tbl->phash_buckets[hash_val]; (n = *np) != NULL;
630 np = &n->next) {
631 if (!memcmp(n->key, pkey, key_len) && n->dev == dev &&
632 net_eq(pneigh_net(n), net)) {
633 *np = n->next;
634 write_unlock_bh(&tbl->lock);
635 if (tbl->pdestructor)
636 tbl->pdestructor(n);
637 if (n->dev)
638 dev_put(n->dev);
639 release_net(pneigh_net(n));
640 kfree(n);
641 return 0;
642 }
643 }
644 write_unlock_bh(&tbl->lock);
645 return -ENOENT;
646}
647
648static int pneigh_ifdown(struct neigh_table *tbl, struct net_device *dev)
649{
650 struct pneigh_entry *n, **np;
651 u32 h;
652
653 for (h = 0; h <= PNEIGH_HASHMASK; h++) {
654 np = &tbl->phash_buckets[h];
655 while ((n = *np) != NULL) {
656 if (!dev || n->dev == dev) {
657 *np = n->next;
658 if (tbl->pdestructor)
659 tbl->pdestructor(n);
660 if (n->dev)
661 dev_put(n->dev);
662 release_net(pneigh_net(n));
663 kfree(n);
664 continue;
665 }
666 np = &n->next;
667 }
668 }
669 return -ENOENT;
670}
671
672static void neigh_parms_destroy(struct neigh_parms *parms);
673
674static inline void neigh_parms_put(struct neigh_parms *parms)
675{
676 if (atomic_dec_and_test(&parms->refcnt))
677 neigh_parms_destroy(parms);
678}
679
680static void neigh_destroy_rcu(struct rcu_head *head)
681{
682 struct neighbour *neigh = container_of(head, struct neighbour, rcu);
683
684 kmem_cache_free(neigh->tbl->kmem_cachep, neigh);
685}
686/*
687 * neighbour must already be out of the table;
688 *
689 */
690void neigh_destroy(struct neighbour *neigh)
691{
692 NEIGH_CACHE_STAT_INC(neigh->tbl, destroys);
693
694 if (!neigh->dead) {
695 printk(KERN_WARNING
696 "Destroying alive neighbour %p\n", neigh);
697 dump_stack();
698 return;
699 }
700
701 if (neigh_del_timer(neigh))
702 printk(KERN_WARNING "Impossible event.\n");
703
704 skb_queue_purge(&neigh->arp_queue);
705
706 dev_put(neigh->dev);
707 neigh_parms_put(neigh->parms);
708
709 NEIGH_PRINTK2("neigh %p is destroyed.\n", neigh);
710
711 atomic_dec(&neigh->tbl->entries);
712 call_rcu(&neigh->rcu, neigh_destroy_rcu);
713}
714EXPORT_SYMBOL(neigh_destroy);
715
716/* Neighbour state is suspicious;
717 disable fast path.
718
719 Called with write_locked neigh.
720 */
721static void neigh_suspect(struct neighbour *neigh)
722{
723 NEIGH_PRINTK2("neigh %p is suspected.\n", neigh);
724
725 neigh->output = neigh->ops->output;
726}
727
728/* Neighbour state is OK;
729 enable fast path.
730
731 Called with write_locked neigh.
732 */
733static void neigh_connect(struct neighbour *neigh)
734{
735 NEIGH_PRINTK2("neigh %p is connected.\n", neigh);
736
737 neigh->output = neigh->ops->connected_output;
738}
739
740static void neigh_periodic_work(struct work_struct *work)
741{
742 struct neigh_table *tbl = container_of(work, struct neigh_table, gc_work.work);
743 struct neighbour *n;
744 struct neighbour __rcu **np;
745 unsigned int i;
746 struct neigh_hash_table *nht;
747
748 NEIGH_CACHE_STAT_INC(tbl, periodic_gc_runs);
749
750 write_lock_bh(&tbl->lock);
751 nht = rcu_dereference_protected(tbl->nht,
752 lockdep_is_held(&tbl->lock));
753
754 /*
755 * periodically recompute ReachableTime from random function
756 */
757
758 if (time_after(jiffies, tbl->last_rand + 300 * HZ)) {
759 struct neigh_parms *p;
760 tbl->last_rand = jiffies;
761 for (p = &tbl->parms; p; p = p->next)
762 p->reachable_time =
763 neigh_rand_reach_time(p->base_reachable_time);
764 }
765
766 for (i = 0 ; i < (1 << nht->hash_shift); i++) {
767 np = &nht->hash_buckets[i];
768
769 while ((n = rcu_dereference_protected(*np,
770 lockdep_is_held(&tbl->lock))) != NULL) {
771 unsigned int state;
772
773 write_lock(&n->lock);
774
775 state = n->nud_state;
776 if (state & (NUD_PERMANENT | NUD_IN_TIMER)) {
777 write_unlock(&n->lock);
778 goto next_elt;
779 }
780
781 if (time_before(n->used, n->confirmed))
782 n->used = n->confirmed;
783
784 if (atomic_read(&n->refcnt) == 1 &&
785 (state == NUD_FAILED ||
786 time_after(jiffies, n->used + n->parms->gc_staletime))) {
787 *np = n->next;
788 n->dead = 1;
789 write_unlock(&n->lock);
790 neigh_cleanup_and_release(n);
791 continue;
792 }
793 write_unlock(&n->lock);
794
795next_elt:
796 np = &n->next;
797 }
798 /*
799 * It's fine to release lock here, even if hash table
800 * grows while we are preempted.
801 */
802 write_unlock_bh(&tbl->lock);
803 cond_resched();
804 write_lock_bh(&tbl->lock);
805 }
806 /* Cycle through all hash buckets every base_reachable_time/2 ticks.
807 * ARP entry timeouts range from 1/2 base_reachable_time to 3/2
808 * base_reachable_time.
809 */
810 schedule_delayed_work(&tbl->gc_work,
811 tbl->parms.base_reachable_time >> 1);
812 write_unlock_bh(&tbl->lock);
813}
814
815static __inline__ int neigh_max_probes(struct neighbour *n)
816{
817 struct neigh_parms *p = n->parms;
818 return (n->nud_state & NUD_PROBE) ?
819 p->ucast_probes :
820 p->ucast_probes + p->app_probes + p->mcast_probes;
821}
822
823static void neigh_invalidate(struct neighbour *neigh)
824 __releases(neigh->lock)
825 __acquires(neigh->lock)
826{
827 struct sk_buff *skb;
828
829 NEIGH_CACHE_STAT_INC(neigh->tbl, res_failed);
830 NEIGH_PRINTK2("neigh %p is failed.\n", neigh);
831 neigh->updated = jiffies;
832
833 /* It is very thin place. report_unreachable is very complicated
834 routine. Particularly, it can hit the same neighbour entry!
835
836 So that, we try to be accurate and avoid dead loop. --ANK
837 */
838 while (neigh->nud_state == NUD_FAILED &&
839 (skb = __skb_dequeue(&neigh->arp_queue)) != NULL) {
840 write_unlock(&neigh->lock);
841 neigh->ops->error_report(neigh, skb);
842 write_lock(&neigh->lock);
843 }
844 skb_queue_purge(&neigh->arp_queue);
845}
846
847/* Called when a timer expires for a neighbour entry. */
848
849static void neigh_timer_handler(unsigned long arg)
850{
851 unsigned long now, next;
852 struct neighbour *neigh = (struct neighbour *)arg;
853 unsigned state;
854 int notify = 0;
855
856 write_lock(&neigh->lock);
857
858 state = neigh->nud_state;
859 now = jiffies;
860 next = now + HZ;
861
862 if (!(state & NUD_IN_TIMER)) {
863#ifndef CONFIG_SMP
864 printk(KERN_WARNING "neigh: timer & !nud_in_timer\n");
865#endif
866 goto out;
867 }
868
869 if (state & NUD_REACHABLE) {
870 if (time_before_eq(now,
871 neigh->confirmed + neigh->parms->reachable_time)) {
872 NEIGH_PRINTK2("neigh %p is still alive.\n", neigh);
873 next = neigh->confirmed + neigh->parms->reachable_time;
874 } else if (time_before_eq(now,
875 neigh->used + neigh->parms->delay_probe_time)) {
876 NEIGH_PRINTK2("neigh %p is delayed.\n", neigh);
877 neigh->nud_state = NUD_DELAY;
878 neigh->updated = jiffies;
879 neigh_suspect(neigh);
880 next = now + neigh->parms->delay_probe_time;
881 } else {
882 NEIGH_PRINTK2("neigh %p is suspected.\n", neigh);
883 neigh->nud_state = NUD_STALE;
884 neigh->updated = jiffies;
885 neigh_suspect(neigh);
886 notify = 1;
887 }
888 } else if (state & NUD_DELAY) {
889 if (time_before_eq(now,
890 neigh->confirmed + neigh->parms->delay_probe_time)) {
891 NEIGH_PRINTK2("neigh %p is now reachable.\n", neigh);
892 neigh->nud_state = NUD_REACHABLE;
893 neigh->updated = jiffies;
894 neigh_connect(neigh);
895 notify = 1;
896 next = neigh->confirmed + neigh->parms->reachable_time;
897 } else {
898 NEIGH_PRINTK2("neigh %p is probed.\n", neigh);
899 neigh->nud_state = NUD_PROBE;
900 neigh->updated = jiffies;
901 atomic_set(&neigh->probes, 0);
902 next = now + neigh->parms->retrans_time;
903 }
904 } else {
905 /* NUD_PROBE|NUD_INCOMPLETE */
906 next = now + neigh->parms->retrans_time;
907 }
908
909 if ((neigh->nud_state & (NUD_INCOMPLETE | NUD_PROBE)) &&
910 atomic_read(&neigh->probes) >= neigh_max_probes(neigh)) {
911 neigh->nud_state = NUD_FAILED;
912 notify = 1;
913 neigh_invalidate(neigh);
914 }
915
916 if (neigh->nud_state & NUD_IN_TIMER) {
917 if (time_before(next, jiffies + HZ/2))
918 next = jiffies + HZ/2;
919 if (!mod_timer(&neigh->timer, next))
920 neigh_hold(neigh);
921 }
922 if (neigh->nud_state & (NUD_INCOMPLETE | NUD_PROBE)) {
923 struct sk_buff *skb = skb_peek(&neigh->arp_queue);
924 /* keep skb alive even if arp_queue overflows */
925 if (skb)
926 skb = skb_copy(skb, GFP_ATOMIC);
927 write_unlock(&neigh->lock);
928 neigh->ops->solicit(neigh, skb);
929 atomic_inc(&neigh->probes);
930 kfree_skb(skb);
931 } else {
932out:
933 write_unlock(&neigh->lock);
934 }
935
936 if (notify)
937 neigh_update_notify(neigh);
938
939 neigh_release(neigh);
940}
941
942int __neigh_event_send(struct neighbour *neigh, struct sk_buff *skb)
943{
944 int rc;
945 unsigned long now;
946
947 write_lock_bh(&neigh->lock);
948
949 rc = 0;
950 if (neigh->nud_state & (NUD_CONNECTED | NUD_DELAY | NUD_PROBE))
951 goto out_unlock_bh;
952
953 now = jiffies;
954
955 if (!(neigh->nud_state & (NUD_STALE | NUD_INCOMPLETE))) {
956 if (neigh->parms->mcast_probes + neigh->parms->app_probes) {
957 atomic_set(&neigh->probes, neigh->parms->ucast_probes);
958 neigh->nud_state = NUD_INCOMPLETE;
959 neigh->updated = jiffies;
960 neigh_add_timer(neigh, now + 1);
961 } else {
962 neigh->nud_state = NUD_FAILED;
963 neigh->updated = jiffies;
964 write_unlock_bh(&neigh->lock);
965
966 kfree_skb(skb);
967 return 1;
968 }
969 } else if (neigh->nud_state & NUD_STALE) {
970 NEIGH_PRINTK2("neigh %p is delayed.\n", neigh);
971 neigh->nud_state = NUD_DELAY;
972 neigh->updated = jiffies;
973 neigh_add_timer(neigh,
974 jiffies + neigh->parms->delay_probe_time);
975 }
976
977 if (neigh->nud_state == NUD_INCOMPLETE) {
978 if (skb) {
979 if (skb_queue_len(&neigh->arp_queue) >=
980 neigh->parms->queue_len) {
981 struct sk_buff *buff;
982 buff = __skb_dequeue(&neigh->arp_queue);
983 kfree_skb(buff);
984 NEIGH_CACHE_STAT_INC(neigh->tbl, unres_discards);
985 }
986 skb_dst_force(skb);
987 __skb_queue_tail(&neigh->arp_queue, skb);
988 }
989 rc = 1;
990 }
991out_unlock_bh:
992 write_unlock_bh(&neigh->lock);
993 return rc;
994}
995EXPORT_SYMBOL(__neigh_event_send);
996
997static void neigh_update_hhs(struct neighbour *neigh)
998{
999 struct hh_cache *hh;
1000 void (*update)(struct hh_cache*, const struct net_device*, const unsigned char *)
1001 = NULL;
1002
1003 if (neigh->dev->header_ops)
1004 update = neigh->dev->header_ops->cache_update;
1005
1006 if (update) {
1007 hh = &neigh->hh;
1008 if (hh->hh_len) {
1009 write_seqlock_bh(&hh->hh_lock);
1010 update(hh, neigh->dev, neigh->ha);
1011 write_sequnlock_bh(&hh->hh_lock);
1012 }
1013 }
1014}
1015
1016
1017
1018/* Generic update routine.
1019 -- lladdr is new lladdr or NULL, if it is not supplied.
1020 -- new is new state.
1021 -- flags
1022 NEIGH_UPDATE_F_OVERRIDE allows to override existing lladdr,
1023 if it is different.
1024 NEIGH_UPDATE_F_WEAK_OVERRIDE will suspect existing "connected"
1025 lladdr instead of overriding it
1026 if it is different.
1027 It also allows to retain current state
1028 if lladdr is unchanged.
1029 NEIGH_UPDATE_F_ADMIN means that the change is administrative.
1030
1031 NEIGH_UPDATE_F_OVERRIDE_ISROUTER allows to override existing
1032 NTF_ROUTER flag.
1033 NEIGH_UPDATE_F_ISROUTER indicates if the neighbour is known as
1034 a router.
1035
1036 Caller MUST hold reference count on the entry.
1037 */
1038
1039int neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new,
1040 u32 flags)
1041{
1042 u8 old;
1043 int err;
1044 int notify = 0;
1045 struct net_device *dev;
1046 int update_isrouter = 0;
1047
1048 write_lock_bh(&neigh->lock);
1049
1050 dev = neigh->dev;
1051 old = neigh->nud_state;
1052 err = -EPERM;
1053
1054 if (!(flags & NEIGH_UPDATE_F_ADMIN) &&
1055 (old & (NUD_NOARP | NUD_PERMANENT)))
1056 goto out;
1057
1058 if (!(new & NUD_VALID)) {
1059 neigh_del_timer(neigh);
1060 if (old & NUD_CONNECTED)
1061 neigh_suspect(neigh);
1062 neigh->nud_state = new;
1063 err = 0;
1064 notify = old & NUD_VALID;
1065 if ((old & (NUD_INCOMPLETE | NUD_PROBE)) &&
1066 (new & NUD_FAILED)) {
1067 neigh_invalidate(neigh);
1068 notify = 1;
1069 }
1070 goto out;
1071 }
1072
1073 /* Compare new lladdr with cached one */
1074 if (!dev->addr_len) {
1075 /* First case: device needs no address. */
1076 lladdr = neigh->ha;
1077 } else if (lladdr) {
1078 /* The second case: if something is already cached
1079 and a new address is proposed:
1080 - compare new & old
1081 - if they are different, check override flag
1082 */
1083 if ((old & NUD_VALID) &&
1084 !memcmp(lladdr, neigh->ha, dev->addr_len))
1085 lladdr = neigh->ha;
1086 } else {
1087 /* No address is supplied; if we know something,
1088 use it, otherwise discard the request.
1089 */
1090 err = -EINVAL;
1091 if (!(old & NUD_VALID))
1092 goto out;
1093 lladdr = neigh->ha;
1094 }
1095
1096 if (new & NUD_CONNECTED)
1097 neigh->confirmed = jiffies;
1098 neigh->updated = jiffies;
1099
1100 /* If entry was valid and address is not changed,
1101 do not change entry state, if new one is STALE.
1102 */
1103 err = 0;
1104 update_isrouter = flags & NEIGH_UPDATE_F_OVERRIDE_ISROUTER;
1105 if (old & NUD_VALID) {
1106 if (lladdr != neigh->ha && !(flags & NEIGH_UPDATE_F_OVERRIDE)) {
1107 update_isrouter = 0;
1108 if ((flags & NEIGH_UPDATE_F_WEAK_OVERRIDE) &&
1109 (old & NUD_CONNECTED)) {
1110 lladdr = neigh->ha;
1111 new = NUD_STALE;
1112 } else
1113 goto out;
1114 } else {
1115 if (lladdr == neigh->ha && new == NUD_STALE &&
1116 ((flags & NEIGH_UPDATE_F_WEAK_OVERRIDE) ||
1117 (old & NUD_CONNECTED))
1118 )
1119 new = old;
1120 }
1121 }
1122
1123 if (new != old) {
1124 neigh_del_timer(neigh);
1125 if (new & NUD_IN_TIMER)
1126 neigh_add_timer(neigh, (jiffies +
1127 ((new & NUD_REACHABLE) ?
1128 neigh->parms->reachable_time :
1129 0)));
1130 neigh->nud_state = new;
1131 }
1132
1133 if (lladdr != neigh->ha) {
1134 write_seqlock(&neigh->ha_lock);
1135 memcpy(&neigh->ha, lladdr, dev->addr_len);
1136 write_sequnlock(&neigh->ha_lock);
1137 neigh_update_hhs(neigh);
1138 if (!(new & NUD_CONNECTED))
1139 neigh->confirmed = jiffies -
1140 (neigh->parms->base_reachable_time << 1);
1141 notify = 1;
1142 }
1143 if (new == old)
1144 goto out;
1145 if (new & NUD_CONNECTED)
1146 neigh_connect(neigh);
1147 else
1148 neigh_suspect(neigh);
1149 if (!(old & NUD_VALID)) {
1150 struct sk_buff *skb;
1151
1152 /* Again: avoid dead loop if something went wrong */
1153
1154 while (neigh->nud_state & NUD_VALID &&
1155 (skb = __skb_dequeue(&neigh->arp_queue)) != NULL) {
1156 struct dst_entry *dst = skb_dst(skb);
1157 struct neighbour *n2, *n1 = neigh;
1158 write_unlock_bh(&neigh->lock);
1159 /* On shaper/eql skb->dst->neighbour != neigh :( */
1160 if (dst && (n2 = dst_get_neighbour(dst)) != NULL)
1161 n1 = n2;
1162 n1->output(n1, skb);
1163 write_lock_bh(&neigh->lock);
1164 }
1165 skb_queue_purge(&neigh->arp_queue);
1166 }
1167out:
1168 if (update_isrouter) {
1169 neigh->flags = (flags & NEIGH_UPDATE_F_ISROUTER) ?
1170 (neigh->flags | NTF_ROUTER) :
1171 (neigh->flags & ~NTF_ROUTER);
1172 }
1173 write_unlock_bh(&neigh->lock);
1174
1175 if (notify)
1176 neigh_update_notify(neigh);
1177
1178 return err;
1179}
1180EXPORT_SYMBOL(neigh_update);
1181
1182struct neighbour *neigh_event_ns(struct neigh_table *tbl,
1183 u8 *lladdr, void *saddr,
1184 struct net_device *dev)
1185{
1186 struct neighbour *neigh = __neigh_lookup(tbl, saddr, dev,
1187 lladdr || !dev->addr_len);
1188 if (neigh)
1189 neigh_update(neigh, lladdr, NUD_STALE,
1190 NEIGH_UPDATE_F_OVERRIDE);
1191 return neigh;
1192}
1193EXPORT_SYMBOL(neigh_event_ns);
1194
1195/* called with read_lock_bh(&n->lock); */
1196static void neigh_hh_init(struct neighbour *n, struct dst_entry *dst)
1197{
1198 struct net_device *dev = dst->dev;
1199 __be16 prot = dst->ops->protocol;
1200 struct hh_cache *hh = &n->hh;
1201
1202 write_lock_bh(&n->lock);
1203
1204 /* Only one thread can come in here and initialize the
1205 * hh_cache entry.
1206 */
1207 if (!hh->hh_len)
1208 dev->header_ops->cache(n, hh, prot);
1209
1210 write_unlock_bh(&n->lock);
1211}
1212
1213/* This function can be used in contexts, where only old dev_queue_xmit
1214 * worked, f.e. if you want to override normal output path (eql, shaper),
1215 * but resolution is not made yet.
1216 */
1217
1218int neigh_compat_output(struct neighbour *neigh, struct sk_buff *skb)
1219{
1220 struct net_device *dev = skb->dev;
1221
1222 __skb_pull(skb, skb_network_offset(skb));
1223
1224 if (dev_hard_header(skb, dev, ntohs(skb->protocol), NULL, NULL,
1225 skb->len) < 0 &&
1226 dev->header_ops->rebuild(skb))
1227 return 0;
1228
1229 return dev_queue_xmit(skb);
1230}
1231EXPORT_SYMBOL(neigh_compat_output);
1232
1233/* Slow and careful. */
1234
1235int neigh_resolve_output(struct neighbour *neigh, struct sk_buff *skb)
1236{
1237 struct dst_entry *dst = skb_dst(skb);
1238 int rc = 0;
1239
1240 if (!dst)
1241 goto discard;
1242
1243 __skb_pull(skb, skb_network_offset(skb));
1244
1245 if (!neigh_event_send(neigh, skb)) {
1246 int err;
1247 struct net_device *dev = neigh->dev;
1248 unsigned int seq;
1249
1250 if (dev->header_ops->cache && !neigh->hh.hh_len)
1251 neigh_hh_init(neigh, dst);
1252
1253 do {
1254 seq = read_seqbegin(&neigh->ha_lock);
1255 err = dev_hard_header(skb, dev, ntohs(skb->protocol),
1256 neigh->ha, NULL, skb->len);
1257 } while (read_seqretry(&neigh->ha_lock, seq));
1258
1259 if (err >= 0)
1260 rc = dev_queue_xmit(skb);
1261 else
1262 goto out_kfree_skb;
1263 }
1264out:
1265 return rc;
1266discard:
1267 NEIGH_PRINTK1("neigh_resolve_output: dst=%p neigh=%p\n",
1268 dst, neigh);
1269out_kfree_skb:
1270 rc = -EINVAL;
1271 kfree_skb(skb);
1272 goto out;
1273}
1274EXPORT_SYMBOL(neigh_resolve_output);
1275
1276/* As fast as possible without hh cache */
1277
1278int neigh_connected_output(struct neighbour *neigh, struct sk_buff *skb)
1279{
1280 struct net_device *dev = neigh->dev;
1281 unsigned int seq;
1282 int err;
1283
1284 __skb_pull(skb, skb_network_offset(skb));
1285
1286 do {
1287 seq = read_seqbegin(&neigh->ha_lock);
1288 err = dev_hard_header(skb, dev, ntohs(skb->protocol),
1289 neigh->ha, NULL, skb->len);
1290 } while (read_seqretry(&neigh->ha_lock, seq));
1291
1292 if (err >= 0)
1293 err = dev_queue_xmit(skb);
1294 else {
1295 err = -EINVAL;
1296 kfree_skb(skb);
1297 }
1298 return err;
1299}
1300EXPORT_SYMBOL(neigh_connected_output);
1301
1302int neigh_direct_output(struct neighbour *neigh, struct sk_buff *skb)
1303{
1304 return dev_queue_xmit(skb);
1305}
1306EXPORT_SYMBOL(neigh_direct_output);
1307
1308static void neigh_proxy_process(unsigned long arg)
1309{
1310 struct neigh_table *tbl = (struct neigh_table *)arg;
1311 long sched_next = 0;
1312 unsigned long now = jiffies;
1313 struct sk_buff *skb, *n;
1314
1315 spin_lock(&tbl->proxy_queue.lock);
1316
1317 skb_queue_walk_safe(&tbl->proxy_queue, skb, n) {
1318 long tdif = NEIGH_CB(skb)->sched_next - now;
1319
1320 if (tdif <= 0) {
1321 struct net_device *dev = skb->dev;
1322
1323 __skb_unlink(skb, &tbl->proxy_queue);
1324 if (tbl->proxy_redo && netif_running(dev)) {
1325 rcu_read_lock();
1326 tbl->proxy_redo(skb);
1327 rcu_read_unlock();
1328 } else {
1329 kfree_skb(skb);
1330 }
1331
1332 dev_put(dev);
1333 } else if (!sched_next || tdif < sched_next)
1334 sched_next = tdif;
1335 }
1336 del_timer(&tbl->proxy_timer);
1337 if (sched_next)
1338 mod_timer(&tbl->proxy_timer, jiffies + sched_next);
1339 spin_unlock(&tbl->proxy_queue.lock);
1340}
1341
1342void pneigh_enqueue(struct neigh_table *tbl, struct neigh_parms *p,
1343 struct sk_buff *skb)
1344{
1345 unsigned long now = jiffies;
1346 unsigned long sched_next = now + (net_random() % p->proxy_delay);
1347
1348 if (tbl->proxy_queue.qlen > p->proxy_qlen) {
1349 kfree_skb(skb);
1350 return;
1351 }
1352
1353 NEIGH_CB(skb)->sched_next = sched_next;
1354 NEIGH_CB(skb)->flags |= LOCALLY_ENQUEUED;
1355
1356 spin_lock(&tbl->proxy_queue.lock);
1357 if (del_timer(&tbl->proxy_timer)) {
1358 if (time_before(tbl->proxy_timer.expires, sched_next))
1359 sched_next = tbl->proxy_timer.expires;
1360 }
1361 skb_dst_drop(skb);
1362 dev_hold(skb->dev);
1363 __skb_queue_tail(&tbl->proxy_queue, skb);
1364 mod_timer(&tbl->proxy_timer, sched_next);
1365 spin_unlock(&tbl->proxy_queue.lock);
1366}
1367EXPORT_SYMBOL(pneigh_enqueue);
1368
1369static inline struct neigh_parms *lookup_neigh_parms(struct neigh_table *tbl,
1370 struct net *net, int ifindex)
1371{
1372 struct neigh_parms *p;
1373
1374 for (p = &tbl->parms; p; p = p->next) {
1375 if ((p->dev && p->dev->ifindex == ifindex && net_eq(neigh_parms_net(p), net)) ||
1376 (!p->dev && !ifindex))
1377 return p;
1378 }
1379
1380 return NULL;
1381}
1382
1383struct neigh_parms *neigh_parms_alloc(struct net_device *dev,
1384 struct neigh_table *tbl)
1385{
1386 struct neigh_parms *p, *ref;
1387 struct net *net = dev_net(dev);
1388 const struct net_device_ops *ops = dev->netdev_ops;
1389
1390 ref = lookup_neigh_parms(tbl, net, 0);
1391 if (!ref)
1392 return NULL;
1393
1394 p = kmemdup(ref, sizeof(*p), GFP_KERNEL);
1395 if (p) {
1396 p->tbl = tbl;
1397 atomic_set(&p->refcnt, 1);
1398 p->reachable_time =
1399 neigh_rand_reach_time(p->base_reachable_time);
1400
1401 if (ops->ndo_neigh_setup && ops->ndo_neigh_setup(dev, p)) {
1402 kfree(p);
1403 return NULL;
1404 }
1405
1406 dev_hold(dev);
1407 p->dev = dev;
1408 write_pnet(&p->net, hold_net(net));
1409 p->sysctl_table = NULL;
1410 write_lock_bh(&tbl->lock);
1411 p->next = tbl->parms.next;
1412 tbl->parms.next = p;
1413 write_unlock_bh(&tbl->lock);
1414 }
1415 return p;
1416}
1417EXPORT_SYMBOL(neigh_parms_alloc);
1418
1419static void neigh_rcu_free_parms(struct rcu_head *head)
1420{
1421 struct neigh_parms *parms =
1422 container_of(head, struct neigh_parms, rcu_head);
1423
1424 neigh_parms_put(parms);
1425}
1426
1427void neigh_parms_release(struct neigh_table *tbl, struct neigh_parms *parms)
1428{
1429 struct neigh_parms **p;
1430
1431 if (!parms || parms == &tbl->parms)
1432 return;
1433 write_lock_bh(&tbl->lock);
1434 for (p = &tbl->parms.next; *p; p = &(*p)->next) {
1435 if (*p == parms) {
1436 *p = parms->next;
1437 parms->dead = 1;
1438 write_unlock_bh(&tbl->lock);
1439 if (parms->dev)
1440 dev_put(parms->dev);
1441 call_rcu(&parms->rcu_head, neigh_rcu_free_parms);
1442 return;
1443 }
1444 }
1445 write_unlock_bh(&tbl->lock);
1446 NEIGH_PRINTK1("neigh_parms_release: not found\n");
1447}
1448EXPORT_SYMBOL(neigh_parms_release);
1449
1450static void neigh_parms_destroy(struct neigh_parms *parms)
1451{
1452 release_net(neigh_parms_net(parms));
1453 kfree(parms);
1454}
1455
1456static struct lock_class_key neigh_table_proxy_queue_class;
1457
1458void neigh_table_init_no_netlink(struct neigh_table *tbl)
1459{
1460 unsigned long now = jiffies;
1461 unsigned long phsize;
1462
1463 write_pnet(&tbl->parms.net, &init_net);
1464 atomic_set(&tbl->parms.refcnt, 1);
1465 tbl->parms.reachable_time =
1466 neigh_rand_reach_time(tbl->parms.base_reachable_time);
1467
1468 if (!tbl->kmem_cachep)
1469 tbl->kmem_cachep =
1470 kmem_cache_create(tbl->id, tbl->entry_size, 0,
1471 SLAB_HWCACHE_ALIGN|SLAB_PANIC,
1472 NULL);
1473 tbl->stats = alloc_percpu(struct neigh_statistics);
1474 if (!tbl->stats)
1475 panic("cannot create neighbour cache statistics");
1476
1477#ifdef CONFIG_PROC_FS
1478 if (!proc_create_data(tbl->id, 0, init_net.proc_net_stat,
1479 &neigh_stat_seq_fops, tbl))
1480 panic("cannot create neighbour proc dir entry");
1481#endif
1482
1483 RCU_INIT_POINTER(tbl->nht, neigh_hash_alloc(3));
1484
1485 phsize = (PNEIGH_HASHMASK + 1) * sizeof(struct pneigh_entry *);
1486 tbl->phash_buckets = kzalloc(phsize, GFP_KERNEL);
1487
1488 if (!tbl->nht || !tbl->phash_buckets)
1489 panic("cannot allocate neighbour cache hashes");
1490
1491 rwlock_init(&tbl->lock);
1492 INIT_DELAYED_WORK_DEFERRABLE(&tbl->gc_work, neigh_periodic_work);
1493 schedule_delayed_work(&tbl->gc_work, tbl->parms.reachable_time);
1494 setup_timer(&tbl->proxy_timer, neigh_proxy_process, (unsigned long)tbl);
1495 skb_queue_head_init_class(&tbl->proxy_queue,
1496 &neigh_table_proxy_queue_class);
1497
1498 tbl->last_flush = now;
1499 tbl->last_rand = now + tbl->parms.reachable_time * 20;
1500}
1501EXPORT_SYMBOL(neigh_table_init_no_netlink);
1502
1503void neigh_table_init(struct neigh_table *tbl)
1504{
1505 struct neigh_table *tmp;
1506
1507 neigh_table_init_no_netlink(tbl);
1508 write_lock(&neigh_tbl_lock);
1509 for (tmp = neigh_tables; tmp; tmp = tmp->next) {
1510 if (tmp->family == tbl->family)
1511 break;
1512 }
1513 tbl->next = neigh_tables;
1514 neigh_tables = tbl;
1515 write_unlock(&neigh_tbl_lock);
1516
1517 if (unlikely(tmp)) {
1518 printk(KERN_ERR "NEIGH: Registering multiple tables for "
1519 "family %d\n", tbl->family);
1520 dump_stack();
1521 }
1522}
1523EXPORT_SYMBOL(neigh_table_init);
1524
1525int neigh_table_clear(struct neigh_table *tbl)
1526{
1527 struct neigh_table **tp;
1528
1529 /* It is not clean... Fix it to unload IPv6 module safely */
1530 cancel_delayed_work_sync(&tbl->gc_work);
1531 del_timer_sync(&tbl->proxy_timer);
1532 pneigh_queue_purge(&tbl->proxy_queue);
1533 neigh_ifdown(tbl, NULL);
1534 if (atomic_read(&tbl->entries))
1535 printk(KERN_CRIT "neighbour leakage\n");
1536 write_lock(&neigh_tbl_lock);
1537 for (tp = &neigh_tables; *tp; tp = &(*tp)->next) {
1538 if (*tp == tbl) {
1539 *tp = tbl->next;
1540 break;
1541 }
1542 }
1543 write_unlock(&neigh_tbl_lock);
1544
1545 call_rcu(&rcu_dereference_protected(tbl->nht, 1)->rcu,
1546 neigh_hash_free_rcu);
1547 tbl->nht = NULL;
1548
1549 kfree(tbl->phash_buckets);
1550 tbl->phash_buckets = NULL;
1551
1552 remove_proc_entry(tbl->id, init_net.proc_net_stat);
1553
1554 free_percpu(tbl->stats);
1555 tbl->stats = NULL;
1556
1557 kmem_cache_destroy(tbl->kmem_cachep);
1558 tbl->kmem_cachep = NULL;
1559
1560 return 0;
1561}
1562EXPORT_SYMBOL(neigh_table_clear);
1563
1564static int neigh_delete(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
1565{
1566 struct net *net = sock_net(skb->sk);
1567 struct ndmsg *ndm;
1568 struct nlattr *dst_attr;
1569 struct neigh_table *tbl;
1570 struct net_device *dev = NULL;
1571 int err = -EINVAL;
1572
1573 ASSERT_RTNL();
1574 if (nlmsg_len(nlh) < sizeof(*ndm))
1575 goto out;
1576
1577 dst_attr = nlmsg_find_attr(nlh, sizeof(*ndm), NDA_DST);
1578 if (dst_attr == NULL)
1579 goto out;
1580
1581 ndm = nlmsg_data(nlh);
1582 if (ndm->ndm_ifindex) {
1583 dev = __dev_get_by_index(net, ndm->ndm_ifindex);
1584 if (dev == NULL) {
1585 err = -ENODEV;
1586 goto out;
1587 }
1588 }
1589
1590 read_lock(&neigh_tbl_lock);
1591 for (tbl = neigh_tables; tbl; tbl = tbl->next) {
1592 struct neighbour *neigh;
1593
1594 if (tbl->family != ndm->ndm_family)
1595 continue;
1596 read_unlock(&neigh_tbl_lock);
1597
1598 if (nla_len(dst_attr) < tbl->key_len)
1599 goto out;
1600
1601 if (ndm->ndm_flags & NTF_PROXY) {
1602 err = pneigh_delete(tbl, net, nla_data(dst_attr), dev);
1603 goto out;
1604 }
1605
1606 if (dev == NULL)
1607 goto out;
1608
1609 neigh = neigh_lookup(tbl, nla_data(dst_attr), dev);
1610 if (neigh == NULL) {
1611 err = -ENOENT;
1612 goto out;
1613 }
1614
1615 err = neigh_update(neigh, NULL, NUD_FAILED,
1616 NEIGH_UPDATE_F_OVERRIDE |
1617 NEIGH_UPDATE_F_ADMIN);
1618 neigh_release(neigh);
1619 goto out;
1620 }
1621 read_unlock(&neigh_tbl_lock);
1622 err = -EAFNOSUPPORT;
1623
1624out:
1625 return err;
1626}
1627
1628static int neigh_add(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
1629{
1630 struct net *net = sock_net(skb->sk);
1631 struct ndmsg *ndm;
1632 struct nlattr *tb[NDA_MAX+1];
1633 struct neigh_table *tbl;
1634 struct net_device *dev = NULL;
1635 int err;
1636
1637 ASSERT_RTNL();
1638 err = nlmsg_parse(nlh, sizeof(*ndm), tb, NDA_MAX, NULL);
1639 if (err < 0)
1640 goto out;
1641
1642 err = -EINVAL;
1643 if (tb[NDA_DST] == NULL)
1644 goto out;
1645
1646 ndm = nlmsg_data(nlh);
1647 if (ndm->ndm_ifindex) {
1648 dev = __dev_get_by_index(net, ndm->ndm_ifindex);
1649 if (dev == NULL) {
1650 err = -ENODEV;
1651 goto out;
1652 }
1653
1654 if (tb[NDA_LLADDR] && nla_len(tb[NDA_LLADDR]) < dev->addr_len)
1655 goto out;
1656 }
1657
1658 read_lock(&neigh_tbl_lock);
1659 for (tbl = neigh_tables; tbl; tbl = tbl->next) {
1660 int flags = NEIGH_UPDATE_F_ADMIN | NEIGH_UPDATE_F_OVERRIDE;
1661 struct neighbour *neigh;
1662 void *dst, *lladdr;
1663
1664 if (tbl->family != ndm->ndm_family)
1665 continue;
1666 read_unlock(&neigh_tbl_lock);
1667
1668 if (nla_len(tb[NDA_DST]) < tbl->key_len)
1669 goto out;
1670 dst = nla_data(tb[NDA_DST]);
1671 lladdr = tb[NDA_LLADDR] ? nla_data(tb[NDA_LLADDR]) : NULL;
1672
1673 if (ndm->ndm_flags & NTF_PROXY) {
1674 struct pneigh_entry *pn;
1675
1676 err = -ENOBUFS;
1677 pn = pneigh_lookup(tbl, net, dst, dev, 1);
1678 if (pn) {
1679 pn->flags = ndm->ndm_flags;
1680 err = 0;
1681 }
1682 goto out;
1683 }
1684
1685 if (dev == NULL)
1686 goto out;
1687
1688 neigh = neigh_lookup(tbl, dst, dev);
1689 if (neigh == NULL) {
1690 if (!(nlh->nlmsg_flags & NLM_F_CREATE)) {
1691 err = -ENOENT;
1692 goto out;
1693 }
1694
1695 neigh = __neigh_lookup_errno(tbl, dst, dev);
1696 if (IS_ERR(neigh)) {
1697 err = PTR_ERR(neigh);
1698 goto out;
1699 }
1700 } else {
1701 if (nlh->nlmsg_flags & NLM_F_EXCL) {
1702 err = -EEXIST;
1703 neigh_release(neigh);
1704 goto out;
1705 }
1706
1707 if (!(nlh->nlmsg_flags & NLM_F_REPLACE))
1708 flags &= ~NEIGH_UPDATE_F_OVERRIDE;
1709 }
1710
1711 if (ndm->ndm_flags & NTF_USE) {
1712 neigh_event_send(neigh, NULL);
1713 err = 0;
1714 } else
1715 err = neigh_update(neigh, lladdr, ndm->ndm_state, flags);
1716 neigh_release(neigh);
1717 goto out;
1718 }
1719
1720 read_unlock(&neigh_tbl_lock);
1721 err = -EAFNOSUPPORT;
1722out:
1723 return err;
1724}
1725
1726static int neightbl_fill_parms(struct sk_buff *skb, struct neigh_parms *parms)
1727{
1728 struct nlattr *nest;
1729
1730 nest = nla_nest_start(skb, NDTA_PARMS);
1731 if (nest == NULL)
1732 return -ENOBUFS;
1733
1734 if (parms->dev)
1735 NLA_PUT_U32(skb, NDTPA_IFINDEX, parms->dev->ifindex);
1736
1737 NLA_PUT_U32(skb, NDTPA_REFCNT, atomic_read(&parms->refcnt));
1738 NLA_PUT_U32(skb, NDTPA_QUEUE_LEN, parms->queue_len);
1739 NLA_PUT_U32(skb, NDTPA_PROXY_QLEN, parms->proxy_qlen);
1740 NLA_PUT_U32(skb, NDTPA_APP_PROBES, parms->app_probes);
1741 NLA_PUT_U32(skb, NDTPA_UCAST_PROBES, parms->ucast_probes);
1742 NLA_PUT_U32(skb, NDTPA_MCAST_PROBES, parms->mcast_probes);
1743 NLA_PUT_MSECS(skb, NDTPA_REACHABLE_TIME, parms->reachable_time);
1744 NLA_PUT_MSECS(skb, NDTPA_BASE_REACHABLE_TIME,
1745 parms->base_reachable_time);
1746 NLA_PUT_MSECS(skb, NDTPA_GC_STALETIME, parms->gc_staletime);
1747 NLA_PUT_MSECS(skb, NDTPA_DELAY_PROBE_TIME, parms->delay_probe_time);
1748 NLA_PUT_MSECS(skb, NDTPA_RETRANS_TIME, parms->retrans_time);
1749 NLA_PUT_MSECS(skb, NDTPA_ANYCAST_DELAY, parms->anycast_delay);
1750 NLA_PUT_MSECS(skb, NDTPA_PROXY_DELAY, parms->proxy_delay);
1751 NLA_PUT_MSECS(skb, NDTPA_LOCKTIME, parms->locktime);
1752
1753 return nla_nest_end(skb, nest);
1754
1755nla_put_failure:
1756 nla_nest_cancel(skb, nest);
1757 return -EMSGSIZE;
1758}
1759
1760static int neightbl_fill_info(struct sk_buff *skb, struct neigh_table *tbl,
1761 u32 pid, u32 seq, int type, int flags)
1762{
1763 struct nlmsghdr *nlh;
1764 struct ndtmsg *ndtmsg;
1765
1766 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndtmsg), flags);
1767 if (nlh == NULL)
1768 return -EMSGSIZE;
1769
1770 ndtmsg = nlmsg_data(nlh);
1771
1772 read_lock_bh(&tbl->lock);
1773 ndtmsg->ndtm_family = tbl->family;
1774 ndtmsg->ndtm_pad1 = 0;
1775 ndtmsg->ndtm_pad2 = 0;
1776
1777 NLA_PUT_STRING(skb, NDTA_NAME, tbl->id);
1778 NLA_PUT_MSECS(skb, NDTA_GC_INTERVAL, tbl->gc_interval);
1779 NLA_PUT_U32(skb, NDTA_THRESH1, tbl->gc_thresh1);
1780 NLA_PUT_U32(skb, NDTA_THRESH2, tbl->gc_thresh2);
1781 NLA_PUT_U32(skb, NDTA_THRESH3, tbl->gc_thresh3);
1782
1783 {
1784 unsigned long now = jiffies;
1785 unsigned int flush_delta = now - tbl->last_flush;
1786 unsigned int rand_delta = now - tbl->last_rand;
1787 struct neigh_hash_table *nht;
1788 struct ndt_config ndc = {
1789 .ndtc_key_len = tbl->key_len,
1790 .ndtc_entry_size = tbl->entry_size,
1791 .ndtc_entries = atomic_read(&tbl->entries),
1792 .ndtc_last_flush = jiffies_to_msecs(flush_delta),
1793 .ndtc_last_rand = jiffies_to_msecs(rand_delta),
1794 .ndtc_proxy_qlen = tbl->proxy_queue.qlen,
1795 };
1796
1797 rcu_read_lock_bh();
1798 nht = rcu_dereference_bh(tbl->nht);
1799 ndc.ndtc_hash_rnd = nht->hash_rnd;
1800 ndc.ndtc_hash_mask = ((1 << nht->hash_shift) - 1);
1801 rcu_read_unlock_bh();
1802
1803 NLA_PUT(skb, NDTA_CONFIG, sizeof(ndc), &ndc);
1804 }
1805
1806 {
1807 int cpu;
1808 struct ndt_stats ndst;
1809
1810 memset(&ndst, 0, sizeof(ndst));
1811
1812 for_each_possible_cpu(cpu) {
1813 struct neigh_statistics *st;
1814
1815 st = per_cpu_ptr(tbl->stats, cpu);
1816 ndst.ndts_allocs += st->allocs;
1817 ndst.ndts_destroys += st->destroys;
1818 ndst.ndts_hash_grows += st->hash_grows;
1819 ndst.ndts_res_failed += st->res_failed;
1820 ndst.ndts_lookups += st->lookups;
1821 ndst.ndts_hits += st->hits;
1822 ndst.ndts_rcv_probes_mcast += st->rcv_probes_mcast;
1823 ndst.ndts_rcv_probes_ucast += st->rcv_probes_ucast;
1824 ndst.ndts_periodic_gc_runs += st->periodic_gc_runs;
1825 ndst.ndts_forced_gc_runs += st->forced_gc_runs;
1826 }
1827
1828 NLA_PUT(skb, NDTA_STATS, sizeof(ndst), &ndst);
1829 }
1830
1831 BUG_ON(tbl->parms.dev);
1832 if (neightbl_fill_parms(skb, &tbl->parms) < 0)
1833 goto nla_put_failure;
1834
1835 read_unlock_bh(&tbl->lock);
1836 return nlmsg_end(skb, nlh);
1837
1838nla_put_failure:
1839 read_unlock_bh(&tbl->lock);
1840 nlmsg_cancel(skb, nlh);
1841 return -EMSGSIZE;
1842}
1843
1844static int neightbl_fill_param_info(struct sk_buff *skb,
1845 struct neigh_table *tbl,
1846 struct neigh_parms *parms,
1847 u32 pid, u32 seq, int type,
1848 unsigned int flags)
1849{
1850 struct ndtmsg *ndtmsg;
1851 struct nlmsghdr *nlh;
1852
1853 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndtmsg), flags);
1854 if (nlh == NULL)
1855 return -EMSGSIZE;
1856
1857 ndtmsg = nlmsg_data(nlh);
1858
1859 read_lock_bh(&tbl->lock);
1860 ndtmsg->ndtm_family = tbl->family;
1861 ndtmsg->ndtm_pad1 = 0;
1862 ndtmsg->ndtm_pad2 = 0;
1863
1864 if (nla_put_string(skb, NDTA_NAME, tbl->id) < 0 ||
1865 neightbl_fill_parms(skb, parms) < 0)
1866 goto errout;
1867
1868 read_unlock_bh(&tbl->lock);
1869 return nlmsg_end(skb, nlh);
1870errout:
1871 read_unlock_bh(&tbl->lock);
1872 nlmsg_cancel(skb, nlh);
1873 return -EMSGSIZE;
1874}
1875
1876static const struct nla_policy nl_neightbl_policy[NDTA_MAX+1] = {
1877 [NDTA_NAME] = { .type = NLA_STRING },
1878 [NDTA_THRESH1] = { .type = NLA_U32 },
1879 [NDTA_THRESH2] = { .type = NLA_U32 },
1880 [NDTA_THRESH3] = { .type = NLA_U32 },
1881 [NDTA_GC_INTERVAL] = { .type = NLA_U64 },
1882 [NDTA_PARMS] = { .type = NLA_NESTED },
1883};
1884
1885static const struct nla_policy nl_ntbl_parm_policy[NDTPA_MAX+1] = {
1886 [NDTPA_IFINDEX] = { .type = NLA_U32 },
1887 [NDTPA_QUEUE_LEN] = { .type = NLA_U32 },
1888 [NDTPA_PROXY_QLEN] = { .type = NLA_U32 },
1889 [NDTPA_APP_PROBES] = { .type = NLA_U32 },
1890 [NDTPA_UCAST_PROBES] = { .type = NLA_U32 },
1891 [NDTPA_MCAST_PROBES] = { .type = NLA_U32 },
1892 [NDTPA_BASE_REACHABLE_TIME] = { .type = NLA_U64 },
1893 [NDTPA_GC_STALETIME] = { .type = NLA_U64 },
1894 [NDTPA_DELAY_PROBE_TIME] = { .type = NLA_U64 },
1895 [NDTPA_RETRANS_TIME] = { .type = NLA_U64 },
1896 [NDTPA_ANYCAST_DELAY] = { .type = NLA_U64 },
1897 [NDTPA_PROXY_DELAY] = { .type = NLA_U64 },
1898 [NDTPA_LOCKTIME] = { .type = NLA_U64 },
1899};
1900
1901static int neightbl_set(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
1902{
1903 struct net *net = sock_net(skb->sk);
1904 struct neigh_table *tbl;
1905 struct ndtmsg *ndtmsg;
1906 struct nlattr *tb[NDTA_MAX+1];
1907 int err;
1908
1909 err = nlmsg_parse(nlh, sizeof(*ndtmsg), tb, NDTA_MAX,
1910 nl_neightbl_policy);
1911 if (err < 0)
1912 goto errout;
1913
1914 if (tb[NDTA_NAME] == NULL) {
1915 err = -EINVAL;
1916 goto errout;
1917 }
1918
1919 ndtmsg = nlmsg_data(nlh);
1920 read_lock(&neigh_tbl_lock);
1921 for (tbl = neigh_tables; tbl; tbl = tbl->next) {
1922 if (ndtmsg->ndtm_family && tbl->family != ndtmsg->ndtm_family)
1923 continue;
1924
1925 if (nla_strcmp(tb[NDTA_NAME], tbl->id) == 0)
1926 break;
1927 }
1928
1929 if (tbl == NULL) {
1930 err = -ENOENT;
1931 goto errout_locked;
1932 }
1933
1934 /*
1935 * We acquire tbl->lock to be nice to the periodic timers and
1936 * make sure they always see a consistent set of values.
1937 */
1938 write_lock_bh(&tbl->lock);
1939
1940 if (tb[NDTA_PARMS]) {
1941 struct nlattr *tbp[NDTPA_MAX+1];
1942 struct neigh_parms *p;
1943 int i, ifindex = 0;
1944
1945 err = nla_parse_nested(tbp, NDTPA_MAX, tb[NDTA_PARMS],
1946 nl_ntbl_parm_policy);
1947 if (err < 0)
1948 goto errout_tbl_lock;
1949
1950 if (tbp[NDTPA_IFINDEX])
1951 ifindex = nla_get_u32(tbp[NDTPA_IFINDEX]);
1952
1953 p = lookup_neigh_parms(tbl, net, ifindex);
1954 if (p == NULL) {
1955 err = -ENOENT;
1956 goto errout_tbl_lock;
1957 }
1958
1959 for (i = 1; i <= NDTPA_MAX; i++) {
1960 if (tbp[i] == NULL)
1961 continue;
1962
1963 switch (i) {
1964 case NDTPA_QUEUE_LEN:
1965 p->queue_len = nla_get_u32(tbp[i]);
1966 break;
1967 case NDTPA_PROXY_QLEN:
1968 p->proxy_qlen = nla_get_u32(tbp[i]);
1969 break;
1970 case NDTPA_APP_PROBES:
1971 p->app_probes = nla_get_u32(tbp[i]);
1972 break;
1973 case NDTPA_UCAST_PROBES:
1974 p->ucast_probes = nla_get_u32(tbp[i]);
1975 break;
1976 case NDTPA_MCAST_PROBES:
1977 p->mcast_probes = nla_get_u32(tbp[i]);
1978 break;
1979 case NDTPA_BASE_REACHABLE_TIME:
1980 p->base_reachable_time = nla_get_msecs(tbp[i]);
1981 break;
1982 case NDTPA_GC_STALETIME:
1983 p->gc_staletime = nla_get_msecs(tbp[i]);
1984 break;
1985 case NDTPA_DELAY_PROBE_TIME:
1986 p->delay_probe_time = nla_get_msecs(tbp[i]);
1987 break;
1988 case NDTPA_RETRANS_TIME:
1989 p->retrans_time = nla_get_msecs(tbp[i]);
1990 break;
1991 case NDTPA_ANYCAST_DELAY:
1992 p->anycast_delay = nla_get_msecs(tbp[i]);
1993 break;
1994 case NDTPA_PROXY_DELAY:
1995 p->proxy_delay = nla_get_msecs(tbp[i]);
1996 break;
1997 case NDTPA_LOCKTIME:
1998 p->locktime = nla_get_msecs(tbp[i]);
1999 break;
2000 }
2001 }
2002 }
2003
2004 if (tb[NDTA_THRESH1])
2005 tbl->gc_thresh1 = nla_get_u32(tb[NDTA_THRESH1]);
2006
2007 if (tb[NDTA_THRESH2])
2008 tbl->gc_thresh2 = nla_get_u32(tb[NDTA_THRESH2]);
2009
2010 if (tb[NDTA_THRESH3])
2011 tbl->gc_thresh3 = nla_get_u32(tb[NDTA_THRESH3]);
2012
2013 if (tb[NDTA_GC_INTERVAL])
2014 tbl->gc_interval = nla_get_msecs(tb[NDTA_GC_INTERVAL]);
2015
2016 err = 0;
2017
2018errout_tbl_lock:
2019 write_unlock_bh(&tbl->lock);
2020errout_locked:
2021 read_unlock(&neigh_tbl_lock);
2022errout:
2023 return err;
2024}
2025
2026static int neightbl_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
2027{
2028 struct net *net = sock_net(skb->sk);
2029 int family, tidx, nidx = 0;
2030 int tbl_skip = cb->args[0];
2031 int neigh_skip = cb->args[1];
2032 struct neigh_table *tbl;
2033
2034 family = ((struct rtgenmsg *) nlmsg_data(cb->nlh))->rtgen_family;
2035
2036 read_lock(&neigh_tbl_lock);
2037 for (tbl = neigh_tables, tidx = 0; tbl; tbl = tbl->next, tidx++) {
2038 struct neigh_parms *p;
2039
2040 if (tidx < tbl_skip || (family && tbl->family != family))
2041 continue;
2042
2043 if (neightbl_fill_info(skb, tbl, NETLINK_CB(cb->skb).pid,
2044 cb->nlh->nlmsg_seq, RTM_NEWNEIGHTBL,
2045 NLM_F_MULTI) <= 0)
2046 break;
2047
2048 for (nidx = 0, p = tbl->parms.next; p; p = p->next) {
2049 if (!net_eq(neigh_parms_net(p), net))
2050 continue;
2051
2052 if (nidx < neigh_skip)
2053 goto next;
2054
2055 if (neightbl_fill_param_info(skb, tbl, p,
2056 NETLINK_CB(cb->skb).pid,
2057 cb->nlh->nlmsg_seq,
2058 RTM_NEWNEIGHTBL,
2059 NLM_F_MULTI) <= 0)
2060 goto out;
2061 next:
2062 nidx++;
2063 }
2064
2065 neigh_skip = 0;
2066 }
2067out:
2068 read_unlock(&neigh_tbl_lock);
2069 cb->args[0] = tidx;
2070 cb->args[1] = nidx;
2071
2072 return skb->len;
2073}
2074
2075static int neigh_fill_info(struct sk_buff *skb, struct neighbour *neigh,
2076 u32 pid, u32 seq, int type, unsigned int flags)
2077{
2078 unsigned long now = jiffies;
2079 struct nda_cacheinfo ci;
2080 struct nlmsghdr *nlh;
2081 struct ndmsg *ndm;
2082
2083 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndm), flags);
2084 if (nlh == NULL)
2085 return -EMSGSIZE;
2086
2087 ndm = nlmsg_data(nlh);
2088 ndm->ndm_family = neigh->ops->family;
2089 ndm->ndm_pad1 = 0;
2090 ndm->ndm_pad2 = 0;
2091 ndm->ndm_flags = neigh->flags;
2092 ndm->ndm_type = neigh->type;
2093 ndm->ndm_ifindex = neigh->dev->ifindex;
2094
2095 NLA_PUT(skb, NDA_DST, neigh->tbl->key_len, neigh->primary_key);
2096
2097 read_lock_bh(&neigh->lock);
2098 ndm->ndm_state = neigh->nud_state;
2099 if (neigh->nud_state & NUD_VALID) {
2100 char haddr[MAX_ADDR_LEN];
2101
2102 neigh_ha_snapshot(haddr, neigh, neigh->dev);
2103 if (nla_put(skb, NDA_LLADDR, neigh->dev->addr_len, haddr) < 0) {
2104 read_unlock_bh(&neigh->lock);
2105 goto nla_put_failure;
2106 }
2107 }
2108
2109 ci.ndm_used = jiffies_to_clock_t(now - neigh->used);
2110 ci.ndm_confirmed = jiffies_to_clock_t(now - neigh->confirmed);
2111 ci.ndm_updated = jiffies_to_clock_t(now - neigh->updated);
2112 ci.ndm_refcnt = atomic_read(&neigh->refcnt) - 1;
2113 read_unlock_bh(&neigh->lock);
2114
2115 NLA_PUT_U32(skb, NDA_PROBES, atomic_read(&neigh->probes));
2116 NLA_PUT(skb, NDA_CACHEINFO, sizeof(ci), &ci);
2117
2118 return nlmsg_end(skb, nlh);
2119
2120nla_put_failure:
2121 nlmsg_cancel(skb, nlh);
2122 return -EMSGSIZE;
2123}
2124
2125static void neigh_update_notify(struct neighbour *neigh)
2126{
2127 call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, neigh);
2128 __neigh_notify(neigh, RTM_NEWNEIGH, 0);
2129}
2130
2131static int neigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb,
2132 struct netlink_callback *cb)
2133{
2134 struct net *net = sock_net(skb->sk);
2135 struct neighbour *n;
2136 int rc, h, s_h = cb->args[1];
2137 int idx, s_idx = idx = cb->args[2];
2138 struct neigh_hash_table *nht;
2139
2140 rcu_read_lock_bh();
2141 nht = rcu_dereference_bh(tbl->nht);
2142
2143 for (h = 0; h < (1 << nht->hash_shift); h++) {
2144 if (h < s_h)
2145 continue;
2146 if (h > s_h)
2147 s_idx = 0;
2148 for (n = rcu_dereference_bh(nht->hash_buckets[h]), idx = 0;
2149 n != NULL;
2150 n = rcu_dereference_bh(n->next)) {
2151 if (!net_eq(dev_net(n->dev), net))
2152 continue;
2153 if (idx < s_idx)
2154 goto next;
2155 if (neigh_fill_info(skb, n, NETLINK_CB(cb->skb).pid,
2156 cb->nlh->nlmsg_seq,
2157 RTM_NEWNEIGH,
2158 NLM_F_MULTI) <= 0) {
2159 rc = -1;
2160 goto out;
2161 }
2162next:
2163 idx++;
2164 }
2165 }
2166 rc = skb->len;
2167out:
2168 rcu_read_unlock_bh();
2169 cb->args[1] = h;
2170 cb->args[2] = idx;
2171 return rc;
2172}
2173
2174static int neigh_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
2175{
2176 struct neigh_table *tbl;
2177 int t, family, s_t;
2178
2179 read_lock(&neigh_tbl_lock);
2180 family = ((struct rtgenmsg *) nlmsg_data(cb->nlh))->rtgen_family;
2181 s_t = cb->args[0];
2182
2183 for (tbl = neigh_tables, t = 0; tbl; tbl = tbl->next, t++) {
2184 if (t < s_t || (family && tbl->family != family))
2185 continue;
2186 if (t > s_t)
2187 memset(&cb->args[1], 0, sizeof(cb->args) -
2188 sizeof(cb->args[0]));
2189 if (neigh_dump_table(tbl, skb, cb) < 0)
2190 break;
2191 }
2192 read_unlock(&neigh_tbl_lock);
2193
2194 cb->args[0] = t;
2195 return skb->len;
2196}
2197
2198void neigh_for_each(struct neigh_table *tbl, void (*cb)(struct neighbour *, void *), void *cookie)
2199{
2200 int chain;
2201 struct neigh_hash_table *nht;
2202
2203 rcu_read_lock_bh();
2204 nht = rcu_dereference_bh(tbl->nht);
2205
2206 read_lock(&tbl->lock); /* avoid resizes */
2207 for (chain = 0; chain < (1 << nht->hash_shift); chain++) {
2208 struct neighbour *n;
2209
2210 for (n = rcu_dereference_bh(nht->hash_buckets[chain]);
2211 n != NULL;
2212 n = rcu_dereference_bh(n->next))
2213 cb(n, cookie);
2214 }
2215 read_unlock(&tbl->lock);
2216 rcu_read_unlock_bh();
2217}
2218EXPORT_SYMBOL(neigh_for_each);
2219
2220/* The tbl->lock must be held as a writer and BH disabled. */
2221void __neigh_for_each_release(struct neigh_table *tbl,
2222 int (*cb)(struct neighbour *))
2223{
2224 int chain;
2225 struct neigh_hash_table *nht;
2226
2227 nht = rcu_dereference_protected(tbl->nht,
2228 lockdep_is_held(&tbl->lock));
2229 for (chain = 0; chain < (1 << nht->hash_shift); chain++) {
2230 struct neighbour *n;
2231 struct neighbour __rcu **np;
2232
2233 np = &nht->hash_buckets[chain];
2234 while ((n = rcu_dereference_protected(*np,
2235 lockdep_is_held(&tbl->lock))) != NULL) {
2236 int release;
2237
2238 write_lock(&n->lock);
2239 release = cb(n);
2240 if (release) {
2241 rcu_assign_pointer(*np,
2242 rcu_dereference_protected(n->next,
2243 lockdep_is_held(&tbl->lock)));
2244 n->dead = 1;
2245 } else
2246 np = &n->next;
2247 write_unlock(&n->lock);
2248 if (release)
2249 neigh_cleanup_and_release(n);
2250 }
2251 }
2252}
2253EXPORT_SYMBOL(__neigh_for_each_release);
2254
2255#ifdef CONFIG_PROC_FS
2256
2257static struct neighbour *neigh_get_first(struct seq_file *seq)
2258{
2259 struct neigh_seq_state *state = seq->private;
2260 struct net *net = seq_file_net(seq);
2261 struct neigh_hash_table *nht = state->nht;
2262 struct neighbour *n = NULL;
2263 int bucket = state->bucket;
2264
2265 state->flags &= ~NEIGH_SEQ_IS_PNEIGH;
2266 for (bucket = 0; bucket < (1 << nht->hash_shift); bucket++) {
2267 n = rcu_dereference_bh(nht->hash_buckets[bucket]);
2268
2269 while (n) {
2270 if (!net_eq(dev_net(n->dev), net))
2271 goto next;
2272 if (state->neigh_sub_iter) {
2273 loff_t fakep = 0;
2274 void *v;
2275
2276 v = state->neigh_sub_iter(state, n, &fakep);
2277 if (!v)
2278 goto next;
2279 }
2280 if (!(state->flags & NEIGH_SEQ_SKIP_NOARP))
2281 break;
2282 if (n->nud_state & ~NUD_NOARP)
2283 break;
2284next:
2285 n = rcu_dereference_bh(n->next);
2286 }
2287
2288 if (n)
2289 break;
2290 }
2291 state->bucket = bucket;
2292
2293 return n;
2294}
2295
2296static struct neighbour *neigh_get_next(struct seq_file *seq,
2297 struct neighbour *n,
2298 loff_t *pos)
2299{
2300 struct neigh_seq_state *state = seq->private;
2301 struct net *net = seq_file_net(seq);
2302 struct neigh_hash_table *nht = state->nht;
2303
2304 if (state->neigh_sub_iter) {
2305 void *v = state->neigh_sub_iter(state, n, pos);
2306 if (v)
2307 return n;
2308 }
2309 n = rcu_dereference_bh(n->next);
2310
2311 while (1) {
2312 while (n) {
2313 if (!net_eq(dev_net(n->dev), net))
2314 goto next;
2315 if (state->neigh_sub_iter) {
2316 void *v = state->neigh_sub_iter(state, n, pos);
2317 if (v)
2318 return n;
2319 goto next;
2320 }
2321 if (!(state->flags & NEIGH_SEQ_SKIP_NOARP))
2322 break;
2323
2324 if (n->nud_state & ~NUD_NOARP)
2325 break;
2326next:
2327 n = rcu_dereference_bh(n->next);
2328 }
2329
2330 if (n)
2331 break;
2332
2333 if (++state->bucket >= (1 << nht->hash_shift))
2334 break;
2335
2336 n = rcu_dereference_bh(nht->hash_buckets[state->bucket]);
2337 }
2338
2339 if (n && pos)
2340 --(*pos);
2341 return n;
2342}
2343
2344static struct neighbour *neigh_get_idx(struct seq_file *seq, loff_t *pos)
2345{
2346 struct neighbour *n = neigh_get_first(seq);
2347
2348 if (n) {
2349 --(*pos);
2350 while (*pos) {
2351 n = neigh_get_next(seq, n, pos);
2352 if (!n)
2353 break;
2354 }
2355 }
2356 return *pos ? NULL : n;
2357}
2358
2359static struct pneigh_entry *pneigh_get_first(struct seq_file *seq)
2360{
2361 struct neigh_seq_state *state = seq->private;
2362 struct net *net = seq_file_net(seq);
2363 struct neigh_table *tbl = state->tbl;
2364 struct pneigh_entry *pn = NULL;
2365 int bucket = state->bucket;
2366
2367 state->flags |= NEIGH_SEQ_IS_PNEIGH;
2368 for (bucket = 0; bucket <= PNEIGH_HASHMASK; bucket++) {
2369 pn = tbl->phash_buckets[bucket];
2370 while (pn && !net_eq(pneigh_net(pn), net))
2371 pn = pn->next;
2372 if (pn)
2373 break;
2374 }
2375 state->bucket = bucket;
2376
2377 return pn;
2378}
2379
2380static struct pneigh_entry *pneigh_get_next(struct seq_file *seq,
2381 struct pneigh_entry *pn,
2382 loff_t *pos)
2383{
2384 struct neigh_seq_state *state = seq->private;
2385 struct net *net = seq_file_net(seq);
2386 struct neigh_table *tbl = state->tbl;
2387
2388 pn = pn->next;
2389 while (!pn) {
2390 if (++state->bucket > PNEIGH_HASHMASK)
2391 break;
2392 pn = tbl->phash_buckets[state->bucket];
2393 while (pn && !net_eq(pneigh_net(pn), net))
2394 pn = pn->next;
2395 if (pn)
2396 break;
2397 }
2398
2399 if (pn && pos)
2400 --(*pos);
2401
2402 return pn;
2403}
2404
2405static struct pneigh_entry *pneigh_get_idx(struct seq_file *seq, loff_t *pos)
2406{
2407 struct pneigh_entry *pn = pneigh_get_first(seq);
2408
2409 if (pn) {
2410 --(*pos);
2411 while (*pos) {
2412 pn = pneigh_get_next(seq, pn, pos);
2413 if (!pn)
2414 break;
2415 }
2416 }
2417 return *pos ? NULL : pn;
2418}
2419
2420static void *neigh_get_idx_any(struct seq_file *seq, loff_t *pos)
2421{
2422 struct neigh_seq_state *state = seq->private;
2423 void *rc;
2424 loff_t idxpos = *pos;
2425
2426 rc = neigh_get_idx(seq, &idxpos);
2427 if (!rc && !(state->flags & NEIGH_SEQ_NEIGH_ONLY))
2428 rc = pneigh_get_idx(seq, &idxpos);
2429
2430 return rc;
2431}
2432
2433void *neigh_seq_start(struct seq_file *seq, loff_t *pos, struct neigh_table *tbl, unsigned int neigh_seq_flags)
2434 __acquires(rcu_bh)
2435{
2436 struct neigh_seq_state *state = seq->private;
2437
2438 state->tbl = tbl;
2439 state->bucket = 0;
2440 state->flags = (neigh_seq_flags & ~NEIGH_SEQ_IS_PNEIGH);
2441
2442 rcu_read_lock_bh();
2443 state->nht = rcu_dereference_bh(tbl->nht);
2444
2445 return *pos ? neigh_get_idx_any(seq, pos) : SEQ_START_TOKEN;
2446}
2447EXPORT_SYMBOL(neigh_seq_start);
2448
2449void *neigh_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2450{
2451 struct neigh_seq_state *state;
2452 void *rc;
2453
2454 if (v == SEQ_START_TOKEN) {
2455 rc = neigh_get_first(seq);
2456 goto out;
2457 }
2458
2459 state = seq->private;
2460 if (!(state->flags & NEIGH_SEQ_IS_PNEIGH)) {
2461 rc = neigh_get_next(seq, v, NULL);
2462 if (rc)
2463 goto out;
2464 if (!(state->flags & NEIGH_SEQ_NEIGH_ONLY))
2465 rc = pneigh_get_first(seq);
2466 } else {
2467 BUG_ON(state->flags & NEIGH_SEQ_NEIGH_ONLY);
2468 rc = pneigh_get_next(seq, v, NULL);
2469 }
2470out:
2471 ++(*pos);
2472 return rc;
2473}
2474EXPORT_SYMBOL(neigh_seq_next);
2475
2476void neigh_seq_stop(struct seq_file *seq, void *v)
2477 __releases(rcu_bh)
2478{
2479 rcu_read_unlock_bh();
2480}
2481EXPORT_SYMBOL(neigh_seq_stop);
2482
2483/* statistics via seq_file */
2484
2485static void *neigh_stat_seq_start(struct seq_file *seq, loff_t *pos)
2486{
2487 struct neigh_table *tbl = seq->private;
2488 int cpu;
2489
2490 if (*pos == 0)
2491 return SEQ_START_TOKEN;
2492
2493 for (cpu = *pos-1; cpu < nr_cpu_ids; ++cpu) {
2494 if (!cpu_possible(cpu))
2495 continue;
2496 *pos = cpu+1;
2497 return per_cpu_ptr(tbl->stats, cpu);
2498 }
2499 return NULL;
2500}
2501
2502static void *neigh_stat_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2503{
2504 struct neigh_table *tbl = seq->private;
2505 int cpu;
2506
2507 for (cpu = *pos; cpu < nr_cpu_ids; ++cpu) {
2508 if (!cpu_possible(cpu))
2509 continue;
2510 *pos = cpu+1;
2511 return per_cpu_ptr(tbl->stats, cpu);
2512 }
2513 return NULL;
2514}
2515
2516static void neigh_stat_seq_stop(struct seq_file *seq, void *v)
2517{
2518
2519}
2520
2521static int neigh_stat_seq_show(struct seq_file *seq, void *v)
2522{
2523 struct neigh_table *tbl = seq->private;
2524 struct neigh_statistics *st = v;
2525
2526 if (v == SEQ_START_TOKEN) {
2527 seq_printf(seq, "entries allocs destroys hash_grows lookups hits res_failed rcv_probes_mcast rcv_probes_ucast periodic_gc_runs forced_gc_runs unresolved_discards\n");
2528 return 0;
2529 }
2530
2531 seq_printf(seq, "%08x %08lx %08lx %08lx %08lx %08lx %08lx "
2532 "%08lx %08lx %08lx %08lx %08lx\n",
2533 atomic_read(&tbl->entries),
2534
2535 st->allocs,
2536 st->destroys,
2537 st->hash_grows,
2538
2539 st->lookups,
2540 st->hits,
2541
2542 st->res_failed,
2543
2544 st->rcv_probes_mcast,
2545 st->rcv_probes_ucast,
2546
2547 st->periodic_gc_runs,
2548 st->forced_gc_runs,
2549 st->unres_discards
2550 );
2551
2552 return 0;
2553}
2554
2555static const struct seq_operations neigh_stat_seq_ops = {
2556 .start = neigh_stat_seq_start,
2557 .next = neigh_stat_seq_next,
2558 .stop = neigh_stat_seq_stop,
2559 .show = neigh_stat_seq_show,
2560};
2561
2562static int neigh_stat_seq_open(struct inode *inode, struct file *file)
2563{
2564 int ret = seq_open(file, &neigh_stat_seq_ops);
2565
2566 if (!ret) {
2567 struct seq_file *sf = file->private_data;
2568 sf->private = PDE(inode)->data;
2569 }
2570 return ret;
2571};
2572
2573static const struct file_operations neigh_stat_seq_fops = {
2574 .owner = THIS_MODULE,
2575 .open = neigh_stat_seq_open,
2576 .read = seq_read,
2577 .llseek = seq_lseek,
2578 .release = seq_release,
2579};
2580
2581#endif /* CONFIG_PROC_FS */
2582
2583static inline size_t neigh_nlmsg_size(void)
2584{
2585 return NLMSG_ALIGN(sizeof(struct ndmsg))
2586 + nla_total_size(MAX_ADDR_LEN) /* NDA_DST */
2587 + nla_total_size(MAX_ADDR_LEN) /* NDA_LLADDR */
2588 + nla_total_size(sizeof(struct nda_cacheinfo))
2589 + nla_total_size(4); /* NDA_PROBES */
2590}
2591
2592static void __neigh_notify(struct neighbour *n, int type, int flags)
2593{
2594 struct net *net = dev_net(n->dev);
2595 struct sk_buff *skb;
2596 int err = -ENOBUFS;
2597
2598 skb = nlmsg_new(neigh_nlmsg_size(), GFP_ATOMIC);
2599 if (skb == NULL)
2600 goto errout;
2601
2602 err = neigh_fill_info(skb, n, 0, 0, type, flags);
2603 if (err < 0) {
2604 /* -EMSGSIZE implies BUG in neigh_nlmsg_size() */
2605 WARN_ON(err == -EMSGSIZE);
2606 kfree_skb(skb);
2607 goto errout;
2608 }
2609 rtnl_notify(skb, net, 0, RTNLGRP_NEIGH, NULL, GFP_ATOMIC);
2610 return;
2611errout:
2612 if (err < 0)
2613 rtnl_set_sk_err(net, RTNLGRP_NEIGH, err);
2614}
2615
2616#ifdef CONFIG_ARPD
2617void neigh_app_ns(struct neighbour *n)
2618{
2619 __neigh_notify(n, RTM_GETNEIGH, NLM_F_REQUEST);
2620}
2621EXPORT_SYMBOL(neigh_app_ns);
2622#endif /* CONFIG_ARPD */
2623
2624#ifdef CONFIG_SYSCTL
2625
2626#define NEIGH_VARS_MAX 19
2627
2628static struct neigh_sysctl_table {
2629 struct ctl_table_header *sysctl_header;
2630 struct ctl_table neigh_vars[NEIGH_VARS_MAX];
2631 char *dev_name;
2632} neigh_sysctl_template __read_mostly = {
2633 .neigh_vars = {
2634 {
2635 .procname = "mcast_solicit",
2636 .maxlen = sizeof(int),
2637 .mode = 0644,
2638 .proc_handler = proc_dointvec,
2639 },
2640 {
2641 .procname = "ucast_solicit",
2642 .maxlen = sizeof(int),
2643 .mode = 0644,
2644 .proc_handler = proc_dointvec,
2645 },
2646 {
2647 .procname = "app_solicit",
2648 .maxlen = sizeof(int),
2649 .mode = 0644,
2650 .proc_handler = proc_dointvec,
2651 },
2652 {
2653 .procname = "retrans_time",
2654 .maxlen = sizeof(int),
2655 .mode = 0644,
2656 .proc_handler = proc_dointvec_userhz_jiffies,
2657 },
2658 {
2659 .procname = "base_reachable_time",
2660 .maxlen = sizeof(int),
2661 .mode = 0644,
2662 .proc_handler = proc_dointvec_jiffies,
2663 },
2664 {
2665 .procname = "delay_first_probe_time",
2666 .maxlen = sizeof(int),
2667 .mode = 0644,
2668 .proc_handler = proc_dointvec_jiffies,
2669 },
2670 {
2671 .procname = "gc_stale_time",
2672 .maxlen = sizeof(int),
2673 .mode = 0644,
2674 .proc_handler = proc_dointvec_jiffies,
2675 },
2676 {
2677 .procname = "unres_qlen",
2678 .maxlen = sizeof(int),
2679 .mode = 0644,
2680 .proc_handler = proc_dointvec,
2681 },
2682 {
2683 .procname = "proxy_qlen",
2684 .maxlen = sizeof(int),
2685 .mode = 0644,
2686 .proc_handler = proc_dointvec,
2687 },
2688 {
2689 .procname = "anycast_delay",
2690 .maxlen = sizeof(int),
2691 .mode = 0644,
2692 .proc_handler = proc_dointvec_userhz_jiffies,
2693 },
2694 {
2695 .procname = "proxy_delay",
2696 .maxlen = sizeof(int),
2697 .mode = 0644,
2698 .proc_handler = proc_dointvec_userhz_jiffies,
2699 },
2700 {
2701 .procname = "locktime",
2702 .maxlen = sizeof(int),
2703 .mode = 0644,
2704 .proc_handler = proc_dointvec_userhz_jiffies,
2705 },
2706 {
2707 .procname = "retrans_time_ms",
2708 .maxlen = sizeof(int),
2709 .mode = 0644,
2710 .proc_handler = proc_dointvec_ms_jiffies,
2711 },
2712 {
2713 .procname = "base_reachable_time_ms",
2714 .maxlen = sizeof(int),
2715 .mode = 0644,
2716 .proc_handler = proc_dointvec_ms_jiffies,
2717 },
2718 {
2719 .procname = "gc_interval",
2720 .maxlen = sizeof(int),
2721 .mode = 0644,
2722 .proc_handler = proc_dointvec_jiffies,
2723 },
2724 {
2725 .procname = "gc_thresh1",
2726 .maxlen = sizeof(int),
2727 .mode = 0644,
2728 .proc_handler = proc_dointvec,
2729 },
2730 {
2731 .procname = "gc_thresh2",
2732 .maxlen = sizeof(int),
2733 .mode = 0644,
2734 .proc_handler = proc_dointvec,
2735 },
2736 {
2737 .procname = "gc_thresh3",
2738 .maxlen = sizeof(int),
2739 .mode = 0644,
2740 .proc_handler = proc_dointvec,
2741 },
2742 {},
2743 },
2744};
2745
2746int neigh_sysctl_register(struct net_device *dev, struct neigh_parms *p,
2747 char *p_name, proc_handler *handler)
2748{
2749 struct neigh_sysctl_table *t;
2750 const char *dev_name_source = NULL;
2751
2752#define NEIGH_CTL_PATH_ROOT 0
2753#define NEIGH_CTL_PATH_PROTO 1
2754#define NEIGH_CTL_PATH_NEIGH 2
2755#define NEIGH_CTL_PATH_DEV 3
2756
2757 struct ctl_path neigh_path[] = {
2758 { .procname = "net", },
2759 { .procname = "proto", },
2760 { .procname = "neigh", },
2761 { .procname = "default", },
2762 { },
2763 };
2764
2765 t = kmemdup(&neigh_sysctl_template, sizeof(*t), GFP_KERNEL);
2766 if (!t)
2767 goto err;
2768
2769 t->neigh_vars[0].data = &p->mcast_probes;
2770 t->neigh_vars[1].data = &p->ucast_probes;
2771 t->neigh_vars[2].data = &p->app_probes;
2772 t->neigh_vars[3].data = &p->retrans_time;
2773 t->neigh_vars[4].data = &p->base_reachable_time;
2774 t->neigh_vars[5].data = &p->delay_probe_time;
2775 t->neigh_vars[6].data = &p->gc_staletime;
2776 t->neigh_vars[7].data = &p->queue_len;
2777 t->neigh_vars[8].data = &p->proxy_qlen;
2778 t->neigh_vars[9].data = &p->anycast_delay;
2779 t->neigh_vars[10].data = &p->proxy_delay;
2780 t->neigh_vars[11].data = &p->locktime;
2781 t->neigh_vars[12].data = &p->retrans_time;
2782 t->neigh_vars[13].data = &p->base_reachable_time;
2783
2784 if (dev) {
2785 dev_name_source = dev->name;
2786 /* Terminate the table early */
2787 memset(&t->neigh_vars[14], 0, sizeof(t->neigh_vars[14]));
2788 } else {
2789 dev_name_source = neigh_path[NEIGH_CTL_PATH_DEV].procname;
2790 t->neigh_vars[14].data = (int *)(p + 1);
2791 t->neigh_vars[15].data = (int *)(p + 1) + 1;
2792 t->neigh_vars[16].data = (int *)(p + 1) + 2;
2793 t->neigh_vars[17].data = (int *)(p + 1) + 3;
2794 }
2795
2796
2797 if (handler) {
2798 /* RetransTime */
2799 t->neigh_vars[3].proc_handler = handler;
2800 t->neigh_vars[3].extra1 = dev;
2801 /* ReachableTime */
2802 t->neigh_vars[4].proc_handler = handler;
2803 t->neigh_vars[4].extra1 = dev;
2804 /* RetransTime (in milliseconds)*/
2805 t->neigh_vars[12].proc_handler = handler;
2806 t->neigh_vars[12].extra1 = dev;
2807 /* ReachableTime (in milliseconds) */
2808 t->neigh_vars[13].proc_handler = handler;
2809 t->neigh_vars[13].extra1 = dev;
2810 }
2811
2812 t->dev_name = kstrdup(dev_name_source, GFP_KERNEL);
2813 if (!t->dev_name)
2814 goto free;
2815
2816 neigh_path[NEIGH_CTL_PATH_DEV].procname = t->dev_name;
2817 neigh_path[NEIGH_CTL_PATH_PROTO].procname = p_name;
2818
2819 t->sysctl_header =
2820 register_net_sysctl_table(neigh_parms_net(p), neigh_path, t->neigh_vars);
2821 if (!t->sysctl_header)
2822 goto free_procname;
2823
2824 p->sysctl_table = t;
2825 return 0;
2826
2827free_procname:
2828 kfree(t->dev_name);
2829free:
2830 kfree(t);
2831err:
2832 return -ENOBUFS;
2833}
2834EXPORT_SYMBOL(neigh_sysctl_register);
2835
2836void neigh_sysctl_unregister(struct neigh_parms *p)
2837{
2838 if (p->sysctl_table) {
2839 struct neigh_sysctl_table *t = p->sysctl_table;
2840 p->sysctl_table = NULL;
2841 unregister_sysctl_table(t->sysctl_header);
2842 kfree(t->dev_name);
2843 kfree(t);
2844 }
2845}
2846EXPORT_SYMBOL(neigh_sysctl_unregister);
2847
2848#endif /* CONFIG_SYSCTL */
2849
2850static int __init neigh_init(void)
2851{
2852 rtnl_register(PF_UNSPEC, RTM_NEWNEIGH, neigh_add, NULL, NULL);
2853 rtnl_register(PF_UNSPEC, RTM_DELNEIGH, neigh_delete, NULL, NULL);
2854 rtnl_register(PF_UNSPEC, RTM_GETNEIGH, NULL, neigh_dump_info, NULL);
2855
2856 rtnl_register(PF_UNSPEC, RTM_GETNEIGHTBL, NULL, neightbl_dump_info,
2857 NULL);
2858 rtnl_register(PF_UNSPEC, RTM_SETNEIGHTBL, neightbl_set, NULL, NULL);
2859
2860 return 0;
2861}
2862
2863subsys_initcall(neigh_init);
2864
1/*
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(struct timer_list *t);
55static void __neigh_notify(struct neighbour *n, int type, int flags,
56 u32 pid);
57static void neigh_update_notify(struct neighbour *neigh, u32 nlmsg_pid);
58static int pneigh_ifdown_and_unlock(struct neigh_table *tbl,
59 struct net_device *dev);
60
61#ifdef CONFIG_PROC_FS
62static const struct file_operations neigh_stat_seq_fops;
63#endif
64
65/*
66 Neighbour hash table buckets are protected with rwlock tbl->lock.
67
68 - All the scans/updates to hash buckets MUST be made under this lock.
69 - NOTHING clever should be made under this lock: no callbacks
70 to protocol backends, no attempts to send something to network.
71 It will result in deadlocks, if backend/driver wants to use neighbour
72 cache.
73 - If the entry requires some non-trivial actions, increase
74 its reference count and release table lock.
75
76 Neighbour entries are protected:
77 - with reference count.
78 - with rwlock neigh->lock
79
80 Reference count prevents destruction.
81
82 neigh->lock mainly serializes ll address data and its validity state.
83 However, the same lock is used to protect another entry fields:
84 - timer
85 - resolution queue
86
87 Again, nothing clever shall be made under neigh->lock,
88 the most complicated procedure, which we allow is dev->hard_header.
89 It is supposed, that dev->hard_header is simplistic and does
90 not make callbacks to neighbour tables.
91 */
92
93static int neigh_blackhole(struct neighbour *neigh, struct sk_buff *skb)
94{
95 kfree_skb(skb);
96 return -ENETDOWN;
97}
98
99static void neigh_cleanup_and_release(struct neighbour *neigh)
100{
101 if (neigh->parms->neigh_cleanup)
102 neigh->parms->neigh_cleanup(neigh);
103
104 __neigh_notify(neigh, RTM_DELNEIGH, 0, 0);
105 call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, neigh);
106 neigh_release(neigh);
107}
108
109/*
110 * It is random distribution in the interval (1/2)*base...(3/2)*base.
111 * It corresponds to default IPv6 settings and is not overridable,
112 * because it is really reasonable choice.
113 */
114
115unsigned long neigh_rand_reach_time(unsigned long base)
116{
117 return base ? (prandom_u32() % base) + (base >> 1) : 0;
118}
119EXPORT_SYMBOL(neigh_rand_reach_time);
120
121
122static bool neigh_del(struct neighbour *n, __u8 state,
123 struct neighbour __rcu **np, struct neigh_table *tbl)
124{
125 bool retval = false;
126
127 write_lock(&n->lock);
128 if (refcount_read(&n->refcnt) == 1 && !(n->nud_state & state)) {
129 struct neighbour *neigh;
130
131 neigh = rcu_dereference_protected(n->next,
132 lockdep_is_held(&tbl->lock));
133 rcu_assign_pointer(*np, neigh);
134 n->dead = 1;
135 retval = true;
136 }
137 write_unlock(&n->lock);
138 if (retval)
139 neigh_cleanup_and_release(n);
140 return retval;
141}
142
143bool neigh_remove_one(struct neighbour *ndel, struct neigh_table *tbl)
144{
145 struct neigh_hash_table *nht;
146 void *pkey = ndel->primary_key;
147 u32 hash_val;
148 struct neighbour *n;
149 struct neighbour __rcu **np;
150
151 nht = rcu_dereference_protected(tbl->nht,
152 lockdep_is_held(&tbl->lock));
153 hash_val = tbl->hash(pkey, ndel->dev, nht->hash_rnd);
154 hash_val = hash_val >> (32 - nht->hash_shift);
155
156 np = &nht->hash_buckets[hash_val];
157 while ((n = rcu_dereference_protected(*np,
158 lockdep_is_held(&tbl->lock)))) {
159 if (n == ndel)
160 return neigh_del(n, 0, np, tbl);
161 np = &n->next;
162 }
163 return false;
164}
165
166static int neigh_forced_gc(struct neigh_table *tbl)
167{
168 int shrunk = 0;
169 int i;
170 struct neigh_hash_table *nht;
171
172 NEIGH_CACHE_STAT_INC(tbl, forced_gc_runs);
173
174 write_lock_bh(&tbl->lock);
175 nht = rcu_dereference_protected(tbl->nht,
176 lockdep_is_held(&tbl->lock));
177 for (i = 0; i < (1 << nht->hash_shift); i++) {
178 struct neighbour *n;
179 struct neighbour __rcu **np;
180
181 np = &nht->hash_buckets[i];
182 while ((n = rcu_dereference_protected(*np,
183 lockdep_is_held(&tbl->lock))) != NULL) {
184 /* Neighbour record may be discarded if:
185 * - nobody refers to it.
186 * - it is not permanent
187 */
188 if (neigh_del(n, NUD_PERMANENT, np, tbl)) {
189 shrunk = 1;
190 continue;
191 }
192 np = &n->next;
193 }
194 }
195
196 tbl->last_flush = jiffies;
197
198 write_unlock_bh(&tbl->lock);
199
200 return shrunk;
201}
202
203static void neigh_add_timer(struct neighbour *n, unsigned long when)
204{
205 neigh_hold(n);
206 if (unlikely(mod_timer(&n->timer, when))) {
207 printk("NEIGH: BUG, double timer add, state is %x\n",
208 n->nud_state);
209 dump_stack();
210 }
211}
212
213static int neigh_del_timer(struct neighbour *n)
214{
215 if ((n->nud_state & NUD_IN_TIMER) &&
216 del_timer(&n->timer)) {
217 neigh_release(n);
218 return 1;
219 }
220 return 0;
221}
222
223static void pneigh_queue_purge(struct sk_buff_head *list)
224{
225 struct sk_buff *skb;
226
227 while ((skb = skb_dequeue(list)) != NULL) {
228 dev_put(skb->dev);
229 kfree_skb(skb);
230 }
231}
232
233static void neigh_flush_dev(struct neigh_table *tbl, struct net_device *dev)
234{
235 int i;
236 struct neigh_hash_table *nht;
237
238 nht = rcu_dereference_protected(tbl->nht,
239 lockdep_is_held(&tbl->lock));
240
241 for (i = 0; i < (1 << nht->hash_shift); i++) {
242 struct neighbour *n;
243 struct neighbour __rcu **np = &nht->hash_buckets[i];
244
245 while ((n = rcu_dereference_protected(*np,
246 lockdep_is_held(&tbl->lock))) != NULL) {
247 if (dev && n->dev != dev) {
248 np = &n->next;
249 continue;
250 }
251 rcu_assign_pointer(*np,
252 rcu_dereference_protected(n->next,
253 lockdep_is_held(&tbl->lock)));
254 write_lock(&n->lock);
255 neigh_del_timer(n);
256 n->dead = 1;
257
258 if (refcount_read(&n->refcnt) != 1) {
259 /* The most unpleasant situation.
260 We must destroy neighbour entry,
261 but someone still uses it.
262
263 The destroy will be delayed until
264 the last user releases us, but
265 we must kill timers etc. and move
266 it to safe state.
267 */
268 __skb_queue_purge(&n->arp_queue);
269 n->arp_queue_len_bytes = 0;
270 n->output = neigh_blackhole;
271 if (n->nud_state & NUD_VALID)
272 n->nud_state = NUD_NOARP;
273 else
274 n->nud_state = NUD_NONE;
275 neigh_dbg(2, "neigh %p is stray\n", n);
276 }
277 write_unlock(&n->lock);
278 neigh_cleanup_and_release(n);
279 }
280 }
281}
282
283void neigh_changeaddr(struct neigh_table *tbl, struct net_device *dev)
284{
285 write_lock_bh(&tbl->lock);
286 neigh_flush_dev(tbl, dev);
287 write_unlock_bh(&tbl->lock);
288}
289EXPORT_SYMBOL(neigh_changeaddr);
290
291int neigh_ifdown(struct neigh_table *tbl, struct net_device *dev)
292{
293 write_lock_bh(&tbl->lock);
294 neigh_flush_dev(tbl, dev);
295 pneigh_ifdown_and_unlock(tbl, dev);
296
297 del_timer_sync(&tbl->proxy_timer);
298 pneigh_queue_purge(&tbl->proxy_queue);
299 return 0;
300}
301EXPORT_SYMBOL(neigh_ifdown);
302
303static struct neighbour *neigh_alloc(struct neigh_table *tbl, struct net_device *dev)
304{
305 struct neighbour *n = NULL;
306 unsigned long now = jiffies;
307 int entries;
308
309 entries = atomic_inc_return(&tbl->entries) - 1;
310 if (entries >= tbl->gc_thresh3 ||
311 (entries >= tbl->gc_thresh2 &&
312 time_after(now, tbl->last_flush + 5 * HZ))) {
313 if (!neigh_forced_gc(tbl) &&
314 entries >= tbl->gc_thresh3) {
315 net_info_ratelimited("%s: neighbor table overflow!\n",
316 tbl->id);
317 NEIGH_CACHE_STAT_INC(tbl, table_fulls);
318 goto out_entries;
319 }
320 }
321
322 n = kzalloc(tbl->entry_size + dev->neigh_priv_len, GFP_ATOMIC);
323 if (!n)
324 goto out_entries;
325
326 __skb_queue_head_init(&n->arp_queue);
327 rwlock_init(&n->lock);
328 seqlock_init(&n->ha_lock);
329 n->updated = n->used = now;
330 n->nud_state = NUD_NONE;
331 n->output = neigh_blackhole;
332 seqlock_init(&n->hh.hh_lock);
333 n->parms = neigh_parms_clone(&tbl->parms);
334 timer_setup(&n->timer, neigh_timer_handler, 0);
335
336 NEIGH_CACHE_STAT_INC(tbl, allocs);
337 n->tbl = tbl;
338 refcount_set(&n->refcnt, 1);
339 n->dead = 1;
340out:
341 return n;
342
343out_entries:
344 atomic_dec(&tbl->entries);
345 goto out;
346}
347
348static void neigh_get_hash_rnd(u32 *x)
349{
350 *x = get_random_u32() | 1;
351}
352
353static struct neigh_hash_table *neigh_hash_alloc(unsigned int shift)
354{
355 size_t size = (1 << shift) * sizeof(struct neighbour *);
356 struct neigh_hash_table *ret;
357 struct neighbour __rcu **buckets;
358 int i;
359
360 ret = kmalloc(sizeof(*ret), GFP_ATOMIC);
361 if (!ret)
362 return NULL;
363 if (size <= PAGE_SIZE)
364 buckets = kzalloc(size, GFP_ATOMIC);
365 else
366 buckets = (struct neighbour __rcu **)
367 __get_free_pages(GFP_ATOMIC | __GFP_ZERO,
368 get_order(size));
369 if (!buckets) {
370 kfree(ret);
371 return NULL;
372 }
373 ret->hash_buckets = buckets;
374 ret->hash_shift = shift;
375 for (i = 0; i < NEIGH_NUM_HASH_RND; i++)
376 neigh_get_hash_rnd(&ret->hash_rnd[i]);
377 return ret;
378}
379
380static void neigh_hash_free_rcu(struct rcu_head *head)
381{
382 struct neigh_hash_table *nht = container_of(head,
383 struct neigh_hash_table,
384 rcu);
385 size_t size = (1 << nht->hash_shift) * sizeof(struct neighbour *);
386 struct neighbour __rcu **buckets = nht->hash_buckets;
387
388 if (size <= PAGE_SIZE)
389 kfree(buckets);
390 else
391 free_pages((unsigned long)buckets, get_order(size));
392 kfree(nht);
393}
394
395static struct neigh_hash_table *neigh_hash_grow(struct neigh_table *tbl,
396 unsigned long new_shift)
397{
398 unsigned int i, hash;
399 struct neigh_hash_table *new_nht, *old_nht;
400
401 NEIGH_CACHE_STAT_INC(tbl, hash_grows);
402
403 old_nht = rcu_dereference_protected(tbl->nht,
404 lockdep_is_held(&tbl->lock));
405 new_nht = neigh_hash_alloc(new_shift);
406 if (!new_nht)
407 return old_nht;
408
409 for (i = 0; i < (1 << old_nht->hash_shift); i++) {
410 struct neighbour *n, *next;
411
412 for (n = rcu_dereference_protected(old_nht->hash_buckets[i],
413 lockdep_is_held(&tbl->lock));
414 n != NULL;
415 n = next) {
416 hash = tbl->hash(n->primary_key, n->dev,
417 new_nht->hash_rnd);
418
419 hash >>= (32 - new_nht->hash_shift);
420 next = rcu_dereference_protected(n->next,
421 lockdep_is_held(&tbl->lock));
422
423 rcu_assign_pointer(n->next,
424 rcu_dereference_protected(
425 new_nht->hash_buckets[hash],
426 lockdep_is_held(&tbl->lock)));
427 rcu_assign_pointer(new_nht->hash_buckets[hash], n);
428 }
429 }
430
431 rcu_assign_pointer(tbl->nht, new_nht);
432 call_rcu(&old_nht->rcu, neigh_hash_free_rcu);
433 return new_nht;
434}
435
436struct neighbour *neigh_lookup(struct neigh_table *tbl, const void *pkey,
437 struct net_device *dev)
438{
439 struct neighbour *n;
440
441 NEIGH_CACHE_STAT_INC(tbl, lookups);
442
443 rcu_read_lock_bh();
444 n = __neigh_lookup_noref(tbl, pkey, dev);
445 if (n) {
446 if (!refcount_inc_not_zero(&n->refcnt))
447 n = NULL;
448 NEIGH_CACHE_STAT_INC(tbl, hits);
449 }
450
451 rcu_read_unlock_bh();
452 return n;
453}
454EXPORT_SYMBOL(neigh_lookup);
455
456struct neighbour *neigh_lookup_nodev(struct neigh_table *tbl, struct net *net,
457 const void *pkey)
458{
459 struct neighbour *n;
460 unsigned int key_len = tbl->key_len;
461 u32 hash_val;
462 struct neigh_hash_table *nht;
463
464 NEIGH_CACHE_STAT_INC(tbl, lookups);
465
466 rcu_read_lock_bh();
467 nht = rcu_dereference_bh(tbl->nht);
468 hash_val = tbl->hash(pkey, NULL, nht->hash_rnd) >> (32 - nht->hash_shift);
469
470 for (n = rcu_dereference_bh(nht->hash_buckets[hash_val]);
471 n != NULL;
472 n = rcu_dereference_bh(n->next)) {
473 if (!memcmp(n->primary_key, pkey, key_len) &&
474 net_eq(dev_net(n->dev), net)) {
475 if (!refcount_inc_not_zero(&n->refcnt))
476 n = NULL;
477 NEIGH_CACHE_STAT_INC(tbl, hits);
478 break;
479 }
480 }
481
482 rcu_read_unlock_bh();
483 return n;
484}
485EXPORT_SYMBOL(neigh_lookup_nodev);
486
487struct neighbour *__neigh_create(struct neigh_table *tbl, const void *pkey,
488 struct net_device *dev, bool want_ref)
489{
490 u32 hash_val;
491 unsigned int key_len = tbl->key_len;
492 int error;
493 struct neighbour *n1, *rc, *n = neigh_alloc(tbl, dev);
494 struct neigh_hash_table *nht;
495
496 if (!n) {
497 rc = ERR_PTR(-ENOBUFS);
498 goto out;
499 }
500
501 memcpy(n->primary_key, pkey, key_len);
502 n->dev = dev;
503 dev_hold(dev);
504
505 /* Protocol specific setup. */
506 if (tbl->constructor && (error = tbl->constructor(n)) < 0) {
507 rc = ERR_PTR(error);
508 goto out_neigh_release;
509 }
510
511 if (dev->netdev_ops->ndo_neigh_construct) {
512 error = dev->netdev_ops->ndo_neigh_construct(dev, n);
513 if (error < 0) {
514 rc = ERR_PTR(error);
515 goto out_neigh_release;
516 }
517 }
518
519 /* Device specific setup. */
520 if (n->parms->neigh_setup &&
521 (error = n->parms->neigh_setup(n)) < 0) {
522 rc = ERR_PTR(error);
523 goto out_neigh_release;
524 }
525
526 n->confirmed = jiffies - (NEIGH_VAR(n->parms, BASE_REACHABLE_TIME) << 1);
527
528 write_lock_bh(&tbl->lock);
529 nht = rcu_dereference_protected(tbl->nht,
530 lockdep_is_held(&tbl->lock));
531
532 if (atomic_read(&tbl->entries) > (1 << nht->hash_shift))
533 nht = neigh_hash_grow(tbl, nht->hash_shift + 1);
534
535 hash_val = tbl->hash(n->primary_key, dev, nht->hash_rnd) >> (32 - nht->hash_shift);
536
537 if (n->parms->dead) {
538 rc = ERR_PTR(-EINVAL);
539 goto out_tbl_unlock;
540 }
541
542 for (n1 = rcu_dereference_protected(nht->hash_buckets[hash_val],
543 lockdep_is_held(&tbl->lock));
544 n1 != NULL;
545 n1 = rcu_dereference_protected(n1->next,
546 lockdep_is_held(&tbl->lock))) {
547 if (dev == n1->dev && !memcmp(n1->primary_key, n->primary_key, key_len)) {
548 if (want_ref)
549 neigh_hold(n1);
550 rc = n1;
551 goto out_tbl_unlock;
552 }
553 }
554
555 n->dead = 0;
556 if (want_ref)
557 neigh_hold(n);
558 rcu_assign_pointer(n->next,
559 rcu_dereference_protected(nht->hash_buckets[hash_val],
560 lockdep_is_held(&tbl->lock)));
561 rcu_assign_pointer(nht->hash_buckets[hash_val], n);
562 write_unlock_bh(&tbl->lock);
563 neigh_dbg(2, "neigh %p is created\n", n);
564 rc = n;
565out:
566 return rc;
567out_tbl_unlock:
568 write_unlock_bh(&tbl->lock);
569out_neigh_release:
570 neigh_release(n);
571 goto out;
572}
573EXPORT_SYMBOL(__neigh_create);
574
575static u32 pneigh_hash(const void *pkey, unsigned int key_len)
576{
577 u32 hash_val = *(u32 *)(pkey + key_len - 4);
578 hash_val ^= (hash_val >> 16);
579 hash_val ^= hash_val >> 8;
580 hash_val ^= hash_val >> 4;
581 hash_val &= PNEIGH_HASHMASK;
582 return hash_val;
583}
584
585static struct pneigh_entry *__pneigh_lookup_1(struct pneigh_entry *n,
586 struct net *net,
587 const void *pkey,
588 unsigned int key_len,
589 struct net_device *dev)
590{
591 while (n) {
592 if (!memcmp(n->key, pkey, key_len) &&
593 net_eq(pneigh_net(n), net) &&
594 (n->dev == dev || !n->dev))
595 return n;
596 n = n->next;
597 }
598 return NULL;
599}
600
601struct pneigh_entry *__pneigh_lookup(struct neigh_table *tbl,
602 struct net *net, const void *pkey, struct net_device *dev)
603{
604 unsigned int key_len = tbl->key_len;
605 u32 hash_val = pneigh_hash(pkey, key_len);
606
607 return __pneigh_lookup_1(tbl->phash_buckets[hash_val],
608 net, pkey, key_len, dev);
609}
610EXPORT_SYMBOL_GPL(__pneigh_lookup);
611
612struct pneigh_entry * pneigh_lookup(struct neigh_table *tbl,
613 struct net *net, const void *pkey,
614 struct net_device *dev, int creat)
615{
616 struct pneigh_entry *n;
617 unsigned int key_len = tbl->key_len;
618 u32 hash_val = pneigh_hash(pkey, key_len);
619
620 read_lock_bh(&tbl->lock);
621 n = __pneigh_lookup_1(tbl->phash_buckets[hash_val],
622 net, pkey, key_len, dev);
623 read_unlock_bh(&tbl->lock);
624
625 if (n || !creat)
626 goto out;
627
628 ASSERT_RTNL();
629
630 n = kmalloc(sizeof(*n) + key_len, GFP_KERNEL);
631 if (!n)
632 goto out;
633
634 write_pnet(&n->net, net);
635 memcpy(n->key, pkey, key_len);
636 n->dev = dev;
637 if (dev)
638 dev_hold(dev);
639
640 if (tbl->pconstructor && tbl->pconstructor(n)) {
641 if (dev)
642 dev_put(dev);
643 kfree(n);
644 n = NULL;
645 goto out;
646 }
647
648 write_lock_bh(&tbl->lock);
649 n->next = tbl->phash_buckets[hash_val];
650 tbl->phash_buckets[hash_val] = n;
651 write_unlock_bh(&tbl->lock);
652out:
653 return n;
654}
655EXPORT_SYMBOL(pneigh_lookup);
656
657
658int pneigh_delete(struct neigh_table *tbl, struct net *net, const void *pkey,
659 struct net_device *dev)
660{
661 struct pneigh_entry *n, **np;
662 unsigned int key_len = tbl->key_len;
663 u32 hash_val = pneigh_hash(pkey, key_len);
664
665 write_lock_bh(&tbl->lock);
666 for (np = &tbl->phash_buckets[hash_val]; (n = *np) != NULL;
667 np = &n->next) {
668 if (!memcmp(n->key, pkey, key_len) && n->dev == dev &&
669 net_eq(pneigh_net(n), net)) {
670 *np = n->next;
671 write_unlock_bh(&tbl->lock);
672 if (tbl->pdestructor)
673 tbl->pdestructor(n);
674 if (n->dev)
675 dev_put(n->dev);
676 kfree(n);
677 return 0;
678 }
679 }
680 write_unlock_bh(&tbl->lock);
681 return -ENOENT;
682}
683
684static int pneigh_ifdown_and_unlock(struct neigh_table *tbl,
685 struct net_device *dev)
686{
687 struct pneigh_entry *n, **np, *freelist = NULL;
688 u32 h;
689
690 for (h = 0; h <= PNEIGH_HASHMASK; h++) {
691 np = &tbl->phash_buckets[h];
692 while ((n = *np) != NULL) {
693 if (!dev || n->dev == dev) {
694 *np = n->next;
695 n->next = freelist;
696 freelist = n;
697 continue;
698 }
699 np = &n->next;
700 }
701 }
702 write_unlock_bh(&tbl->lock);
703 while ((n = freelist)) {
704 freelist = n->next;
705 n->next = NULL;
706 if (tbl->pdestructor)
707 tbl->pdestructor(n);
708 if (n->dev)
709 dev_put(n->dev);
710 kfree(n);
711 }
712 return -ENOENT;
713}
714
715static void neigh_parms_destroy(struct neigh_parms *parms);
716
717static inline void neigh_parms_put(struct neigh_parms *parms)
718{
719 if (refcount_dec_and_test(&parms->refcnt))
720 neigh_parms_destroy(parms);
721}
722
723/*
724 * neighbour must already be out of the table;
725 *
726 */
727void neigh_destroy(struct neighbour *neigh)
728{
729 struct net_device *dev = neigh->dev;
730
731 NEIGH_CACHE_STAT_INC(neigh->tbl, destroys);
732
733 if (!neigh->dead) {
734 pr_warn("Destroying alive neighbour %p\n", neigh);
735 dump_stack();
736 return;
737 }
738
739 if (neigh_del_timer(neigh))
740 pr_warn("Impossible event\n");
741
742 write_lock_bh(&neigh->lock);
743 __skb_queue_purge(&neigh->arp_queue);
744 write_unlock_bh(&neigh->lock);
745 neigh->arp_queue_len_bytes = 0;
746
747 if (dev->netdev_ops->ndo_neigh_destroy)
748 dev->netdev_ops->ndo_neigh_destroy(dev, neigh);
749
750 dev_put(dev);
751 neigh_parms_put(neigh->parms);
752
753 neigh_dbg(2, "neigh %p is destroyed\n", neigh);
754
755 atomic_dec(&neigh->tbl->entries);
756 kfree_rcu(neigh, rcu);
757}
758EXPORT_SYMBOL(neigh_destroy);
759
760/* Neighbour state is suspicious;
761 disable fast path.
762
763 Called with write_locked neigh.
764 */
765static void neigh_suspect(struct neighbour *neigh)
766{
767 neigh_dbg(2, "neigh %p is suspected\n", neigh);
768
769 neigh->output = neigh->ops->output;
770}
771
772/* Neighbour state is OK;
773 enable fast path.
774
775 Called with write_locked neigh.
776 */
777static void neigh_connect(struct neighbour *neigh)
778{
779 neigh_dbg(2, "neigh %p is connected\n", neigh);
780
781 neigh->output = neigh->ops->connected_output;
782}
783
784static void neigh_periodic_work(struct work_struct *work)
785{
786 struct neigh_table *tbl = container_of(work, struct neigh_table, gc_work.work);
787 struct neighbour *n;
788 struct neighbour __rcu **np;
789 unsigned int i;
790 struct neigh_hash_table *nht;
791
792 NEIGH_CACHE_STAT_INC(tbl, periodic_gc_runs);
793
794 write_lock_bh(&tbl->lock);
795 nht = rcu_dereference_protected(tbl->nht,
796 lockdep_is_held(&tbl->lock));
797
798 /*
799 * periodically recompute ReachableTime from random function
800 */
801
802 if (time_after(jiffies, tbl->last_rand + 300 * HZ)) {
803 struct neigh_parms *p;
804 tbl->last_rand = jiffies;
805 list_for_each_entry(p, &tbl->parms_list, list)
806 p->reachable_time =
807 neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME));
808 }
809
810 if (atomic_read(&tbl->entries) < tbl->gc_thresh1)
811 goto out;
812
813 for (i = 0 ; i < (1 << nht->hash_shift); i++) {
814 np = &nht->hash_buckets[i];
815
816 while ((n = rcu_dereference_protected(*np,
817 lockdep_is_held(&tbl->lock))) != NULL) {
818 unsigned int state;
819
820 write_lock(&n->lock);
821
822 state = n->nud_state;
823 if (state & (NUD_PERMANENT | NUD_IN_TIMER)) {
824 write_unlock(&n->lock);
825 goto next_elt;
826 }
827
828 if (time_before(n->used, n->confirmed))
829 n->used = n->confirmed;
830
831 if (refcount_read(&n->refcnt) == 1 &&
832 (state == NUD_FAILED ||
833 time_after(jiffies, n->used + NEIGH_VAR(n->parms, GC_STALETIME)))) {
834 *np = n->next;
835 n->dead = 1;
836 write_unlock(&n->lock);
837 neigh_cleanup_and_release(n);
838 continue;
839 }
840 write_unlock(&n->lock);
841
842next_elt:
843 np = &n->next;
844 }
845 /*
846 * It's fine to release lock here, even if hash table
847 * grows while we are preempted.
848 */
849 write_unlock_bh(&tbl->lock);
850 cond_resched();
851 write_lock_bh(&tbl->lock);
852 nht = rcu_dereference_protected(tbl->nht,
853 lockdep_is_held(&tbl->lock));
854 }
855out:
856 /* Cycle through all hash buckets every BASE_REACHABLE_TIME/2 ticks.
857 * ARP entry timeouts range from 1/2 BASE_REACHABLE_TIME to 3/2
858 * BASE_REACHABLE_TIME.
859 */
860 queue_delayed_work(system_power_efficient_wq, &tbl->gc_work,
861 NEIGH_VAR(&tbl->parms, BASE_REACHABLE_TIME) >> 1);
862 write_unlock_bh(&tbl->lock);
863}
864
865static __inline__ int neigh_max_probes(struct neighbour *n)
866{
867 struct neigh_parms *p = n->parms;
868 return NEIGH_VAR(p, UCAST_PROBES) + NEIGH_VAR(p, APP_PROBES) +
869 (n->nud_state & NUD_PROBE ? NEIGH_VAR(p, MCAST_REPROBES) :
870 NEIGH_VAR(p, MCAST_PROBES));
871}
872
873static void neigh_invalidate(struct neighbour *neigh)
874 __releases(neigh->lock)
875 __acquires(neigh->lock)
876{
877 struct sk_buff *skb;
878
879 NEIGH_CACHE_STAT_INC(neigh->tbl, res_failed);
880 neigh_dbg(2, "neigh %p is failed\n", neigh);
881 neigh->updated = jiffies;
882
883 /* It is very thin place. report_unreachable is very complicated
884 routine. Particularly, it can hit the same neighbour entry!
885
886 So that, we try to be accurate and avoid dead loop. --ANK
887 */
888 while (neigh->nud_state == NUD_FAILED &&
889 (skb = __skb_dequeue(&neigh->arp_queue)) != NULL) {
890 write_unlock(&neigh->lock);
891 neigh->ops->error_report(neigh, skb);
892 write_lock(&neigh->lock);
893 }
894 __skb_queue_purge(&neigh->arp_queue);
895 neigh->arp_queue_len_bytes = 0;
896}
897
898static void neigh_probe(struct neighbour *neigh)
899 __releases(neigh->lock)
900{
901 struct sk_buff *skb = skb_peek_tail(&neigh->arp_queue);
902 /* keep skb alive even if arp_queue overflows */
903 if (skb)
904 skb = skb_clone(skb, GFP_ATOMIC);
905 write_unlock(&neigh->lock);
906 if (neigh->ops->solicit)
907 neigh->ops->solicit(neigh, skb);
908 atomic_inc(&neigh->probes);
909 kfree_skb(skb);
910}
911
912/* Called when a timer expires for a neighbour entry. */
913
914static void neigh_timer_handler(struct timer_list *t)
915{
916 unsigned long now, next;
917 struct neighbour *neigh = from_timer(neigh, t, timer);
918 unsigned int state;
919 int notify = 0;
920
921 write_lock(&neigh->lock);
922
923 state = neigh->nud_state;
924 now = jiffies;
925 next = now + HZ;
926
927 if (!(state & NUD_IN_TIMER))
928 goto out;
929
930 if (state & NUD_REACHABLE) {
931 if (time_before_eq(now,
932 neigh->confirmed + neigh->parms->reachable_time)) {
933 neigh_dbg(2, "neigh %p is still alive\n", neigh);
934 next = neigh->confirmed + neigh->parms->reachable_time;
935 } else if (time_before_eq(now,
936 neigh->used +
937 NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME))) {
938 neigh_dbg(2, "neigh %p is delayed\n", neigh);
939 neigh->nud_state = NUD_DELAY;
940 neigh->updated = jiffies;
941 neigh_suspect(neigh);
942 next = now + NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME);
943 } else {
944 neigh_dbg(2, "neigh %p is suspected\n", neigh);
945 neigh->nud_state = NUD_STALE;
946 neigh->updated = jiffies;
947 neigh_suspect(neigh);
948 notify = 1;
949 }
950 } else if (state & NUD_DELAY) {
951 if (time_before_eq(now,
952 neigh->confirmed +
953 NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME))) {
954 neigh_dbg(2, "neigh %p is now reachable\n", neigh);
955 neigh->nud_state = NUD_REACHABLE;
956 neigh->updated = jiffies;
957 neigh_connect(neigh);
958 notify = 1;
959 next = neigh->confirmed + neigh->parms->reachable_time;
960 } else {
961 neigh_dbg(2, "neigh %p is probed\n", neigh);
962 neigh->nud_state = NUD_PROBE;
963 neigh->updated = jiffies;
964 atomic_set(&neigh->probes, 0);
965 notify = 1;
966 next = now + NEIGH_VAR(neigh->parms, RETRANS_TIME);
967 }
968 } else {
969 /* NUD_PROBE|NUD_INCOMPLETE */
970 next = now + NEIGH_VAR(neigh->parms, RETRANS_TIME);
971 }
972
973 if ((neigh->nud_state & (NUD_INCOMPLETE | NUD_PROBE)) &&
974 atomic_read(&neigh->probes) >= neigh_max_probes(neigh)) {
975 neigh->nud_state = NUD_FAILED;
976 notify = 1;
977 neigh_invalidate(neigh);
978 goto out;
979 }
980
981 if (neigh->nud_state & NUD_IN_TIMER) {
982 if (time_before(next, jiffies + HZ/2))
983 next = jiffies + HZ/2;
984 if (!mod_timer(&neigh->timer, next))
985 neigh_hold(neigh);
986 }
987 if (neigh->nud_state & (NUD_INCOMPLETE | NUD_PROBE)) {
988 neigh_probe(neigh);
989 } else {
990out:
991 write_unlock(&neigh->lock);
992 }
993
994 if (notify)
995 neigh_update_notify(neigh, 0);
996
997 neigh_release(neigh);
998}
999
1000int __neigh_event_send(struct neighbour *neigh, struct sk_buff *skb)
1001{
1002 int rc;
1003 bool immediate_probe = false;
1004
1005 write_lock_bh(&neigh->lock);
1006
1007 rc = 0;
1008 if (neigh->nud_state & (NUD_CONNECTED | NUD_DELAY | NUD_PROBE))
1009 goto out_unlock_bh;
1010 if (neigh->dead)
1011 goto out_dead;
1012
1013 if (!(neigh->nud_state & (NUD_STALE | NUD_INCOMPLETE))) {
1014 if (NEIGH_VAR(neigh->parms, MCAST_PROBES) +
1015 NEIGH_VAR(neigh->parms, APP_PROBES)) {
1016 unsigned long next, now = jiffies;
1017
1018 atomic_set(&neigh->probes,
1019 NEIGH_VAR(neigh->parms, UCAST_PROBES));
1020 neigh->nud_state = NUD_INCOMPLETE;
1021 neigh->updated = now;
1022 next = now + max(NEIGH_VAR(neigh->parms, RETRANS_TIME),
1023 HZ/2);
1024 neigh_add_timer(neigh, next);
1025 immediate_probe = true;
1026 } else {
1027 neigh->nud_state = NUD_FAILED;
1028 neigh->updated = jiffies;
1029 write_unlock_bh(&neigh->lock);
1030
1031 kfree_skb(skb);
1032 return 1;
1033 }
1034 } else if (neigh->nud_state & NUD_STALE) {
1035 neigh_dbg(2, "neigh %p is delayed\n", neigh);
1036 neigh->nud_state = NUD_DELAY;
1037 neigh->updated = jiffies;
1038 neigh_add_timer(neigh, jiffies +
1039 NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME));
1040 }
1041
1042 if (neigh->nud_state == NUD_INCOMPLETE) {
1043 if (skb) {
1044 while (neigh->arp_queue_len_bytes + skb->truesize >
1045 NEIGH_VAR(neigh->parms, QUEUE_LEN_BYTES)) {
1046 struct sk_buff *buff;
1047
1048 buff = __skb_dequeue(&neigh->arp_queue);
1049 if (!buff)
1050 break;
1051 neigh->arp_queue_len_bytes -= buff->truesize;
1052 kfree_skb(buff);
1053 NEIGH_CACHE_STAT_INC(neigh->tbl, unres_discards);
1054 }
1055 skb_dst_force(skb);
1056 __skb_queue_tail(&neigh->arp_queue, skb);
1057 neigh->arp_queue_len_bytes += skb->truesize;
1058 }
1059 rc = 1;
1060 }
1061out_unlock_bh:
1062 if (immediate_probe)
1063 neigh_probe(neigh);
1064 else
1065 write_unlock(&neigh->lock);
1066 local_bh_enable();
1067 return rc;
1068
1069out_dead:
1070 if (neigh->nud_state & NUD_STALE)
1071 goto out_unlock_bh;
1072 write_unlock_bh(&neigh->lock);
1073 kfree_skb(skb);
1074 return 1;
1075}
1076EXPORT_SYMBOL(__neigh_event_send);
1077
1078static void neigh_update_hhs(struct neighbour *neigh)
1079{
1080 struct hh_cache *hh;
1081 void (*update)(struct hh_cache*, const struct net_device*, const unsigned char *)
1082 = NULL;
1083
1084 if (neigh->dev->header_ops)
1085 update = neigh->dev->header_ops->cache_update;
1086
1087 if (update) {
1088 hh = &neigh->hh;
1089 if (hh->hh_len) {
1090 write_seqlock_bh(&hh->hh_lock);
1091 update(hh, neigh->dev, neigh->ha);
1092 write_sequnlock_bh(&hh->hh_lock);
1093 }
1094 }
1095}
1096
1097
1098
1099/* Generic update routine.
1100 -- lladdr is new lladdr or NULL, if it is not supplied.
1101 -- new is new state.
1102 -- flags
1103 NEIGH_UPDATE_F_OVERRIDE allows to override existing lladdr,
1104 if it is different.
1105 NEIGH_UPDATE_F_WEAK_OVERRIDE will suspect existing "connected"
1106 lladdr instead of overriding it
1107 if it is different.
1108 NEIGH_UPDATE_F_ADMIN means that the change is administrative.
1109
1110 NEIGH_UPDATE_F_OVERRIDE_ISROUTER allows to override existing
1111 NTF_ROUTER flag.
1112 NEIGH_UPDATE_F_ISROUTER indicates if the neighbour is known as
1113 a router.
1114
1115 Caller MUST hold reference count on the entry.
1116 */
1117
1118int neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new,
1119 u32 flags, u32 nlmsg_pid)
1120{
1121 u8 old;
1122 int err;
1123 int notify = 0;
1124 struct net_device *dev;
1125 int update_isrouter = 0;
1126
1127 write_lock_bh(&neigh->lock);
1128
1129 dev = neigh->dev;
1130 old = neigh->nud_state;
1131 err = -EPERM;
1132
1133 if (!(flags & NEIGH_UPDATE_F_ADMIN) &&
1134 (old & (NUD_NOARP | NUD_PERMANENT)))
1135 goto out;
1136 if (neigh->dead)
1137 goto out;
1138
1139 if (!(new & NUD_VALID)) {
1140 neigh_del_timer(neigh);
1141 if (old & NUD_CONNECTED)
1142 neigh_suspect(neigh);
1143 neigh->nud_state = new;
1144 err = 0;
1145 notify = old & NUD_VALID;
1146 if ((old & (NUD_INCOMPLETE | NUD_PROBE)) &&
1147 (new & NUD_FAILED)) {
1148 neigh_invalidate(neigh);
1149 notify = 1;
1150 }
1151 goto out;
1152 }
1153
1154 /* Compare new lladdr with cached one */
1155 if (!dev->addr_len) {
1156 /* First case: device needs no address. */
1157 lladdr = neigh->ha;
1158 } else if (lladdr) {
1159 /* The second case: if something is already cached
1160 and a new address is proposed:
1161 - compare new & old
1162 - if they are different, check override flag
1163 */
1164 if ((old & NUD_VALID) &&
1165 !memcmp(lladdr, neigh->ha, dev->addr_len))
1166 lladdr = neigh->ha;
1167 } else {
1168 /* No address is supplied; if we know something,
1169 use it, otherwise discard the request.
1170 */
1171 err = -EINVAL;
1172 if (!(old & NUD_VALID))
1173 goto out;
1174 lladdr = neigh->ha;
1175 }
1176
1177 /* If entry was valid and address is not changed,
1178 do not change entry state, if new one is STALE.
1179 */
1180 err = 0;
1181 update_isrouter = flags & NEIGH_UPDATE_F_OVERRIDE_ISROUTER;
1182 if (old & NUD_VALID) {
1183 if (lladdr != neigh->ha && !(flags & NEIGH_UPDATE_F_OVERRIDE)) {
1184 update_isrouter = 0;
1185 if ((flags & NEIGH_UPDATE_F_WEAK_OVERRIDE) &&
1186 (old & NUD_CONNECTED)) {
1187 lladdr = neigh->ha;
1188 new = NUD_STALE;
1189 } else
1190 goto out;
1191 } else {
1192 if (lladdr == neigh->ha && new == NUD_STALE &&
1193 !(flags & NEIGH_UPDATE_F_ADMIN))
1194 new = old;
1195 }
1196 }
1197
1198 /* Update timestamps only once we know we will make a change to the
1199 * neighbour entry. Otherwise we risk to move the locktime window with
1200 * noop updates and ignore relevant ARP updates.
1201 */
1202 if (new != old || lladdr != neigh->ha) {
1203 if (new & NUD_CONNECTED)
1204 neigh->confirmed = jiffies;
1205 neigh->updated = jiffies;
1206 }
1207
1208 if (new != old) {
1209 neigh_del_timer(neigh);
1210 if (new & NUD_PROBE)
1211 atomic_set(&neigh->probes, 0);
1212 if (new & NUD_IN_TIMER)
1213 neigh_add_timer(neigh, (jiffies +
1214 ((new & NUD_REACHABLE) ?
1215 neigh->parms->reachable_time :
1216 0)));
1217 neigh->nud_state = new;
1218 notify = 1;
1219 }
1220
1221 if (lladdr != neigh->ha) {
1222 write_seqlock(&neigh->ha_lock);
1223 memcpy(&neigh->ha, lladdr, dev->addr_len);
1224 write_sequnlock(&neigh->ha_lock);
1225 neigh_update_hhs(neigh);
1226 if (!(new & NUD_CONNECTED))
1227 neigh->confirmed = jiffies -
1228 (NEIGH_VAR(neigh->parms, BASE_REACHABLE_TIME) << 1);
1229 notify = 1;
1230 }
1231 if (new == old)
1232 goto out;
1233 if (new & NUD_CONNECTED)
1234 neigh_connect(neigh);
1235 else
1236 neigh_suspect(neigh);
1237 if (!(old & NUD_VALID)) {
1238 struct sk_buff *skb;
1239
1240 /* Again: avoid dead loop if something went wrong */
1241
1242 while (neigh->nud_state & NUD_VALID &&
1243 (skb = __skb_dequeue(&neigh->arp_queue)) != NULL) {
1244 struct dst_entry *dst = skb_dst(skb);
1245 struct neighbour *n2, *n1 = neigh;
1246 write_unlock_bh(&neigh->lock);
1247
1248 rcu_read_lock();
1249
1250 /* Why not just use 'neigh' as-is? The problem is that
1251 * things such as shaper, eql, and sch_teql can end up
1252 * using alternative, different, neigh objects to output
1253 * the packet in the output path. So what we need to do
1254 * here is re-lookup the top-level neigh in the path so
1255 * we can reinject the packet there.
1256 */
1257 n2 = NULL;
1258 if (dst) {
1259 n2 = dst_neigh_lookup_skb(dst, skb);
1260 if (n2)
1261 n1 = n2;
1262 }
1263 n1->output(n1, skb);
1264 if (n2)
1265 neigh_release(n2);
1266 rcu_read_unlock();
1267
1268 write_lock_bh(&neigh->lock);
1269 }
1270 __skb_queue_purge(&neigh->arp_queue);
1271 neigh->arp_queue_len_bytes = 0;
1272 }
1273out:
1274 if (update_isrouter) {
1275 neigh->flags = (flags & NEIGH_UPDATE_F_ISROUTER) ?
1276 (neigh->flags | NTF_ROUTER) :
1277 (neigh->flags & ~NTF_ROUTER);
1278 }
1279 write_unlock_bh(&neigh->lock);
1280
1281 if (notify)
1282 neigh_update_notify(neigh, nlmsg_pid);
1283
1284 return err;
1285}
1286EXPORT_SYMBOL(neigh_update);
1287
1288/* Update the neigh to listen temporarily for probe responses, even if it is
1289 * in a NUD_FAILED state. The caller has to hold neigh->lock for writing.
1290 */
1291void __neigh_set_probe_once(struct neighbour *neigh)
1292{
1293 if (neigh->dead)
1294 return;
1295 neigh->updated = jiffies;
1296 if (!(neigh->nud_state & NUD_FAILED))
1297 return;
1298 neigh->nud_state = NUD_INCOMPLETE;
1299 atomic_set(&neigh->probes, neigh_max_probes(neigh));
1300 neigh_add_timer(neigh,
1301 jiffies + NEIGH_VAR(neigh->parms, RETRANS_TIME));
1302}
1303EXPORT_SYMBOL(__neigh_set_probe_once);
1304
1305struct neighbour *neigh_event_ns(struct neigh_table *tbl,
1306 u8 *lladdr, void *saddr,
1307 struct net_device *dev)
1308{
1309 struct neighbour *neigh = __neigh_lookup(tbl, saddr, dev,
1310 lladdr || !dev->addr_len);
1311 if (neigh)
1312 neigh_update(neigh, lladdr, NUD_STALE,
1313 NEIGH_UPDATE_F_OVERRIDE, 0);
1314 return neigh;
1315}
1316EXPORT_SYMBOL(neigh_event_ns);
1317
1318/* called with read_lock_bh(&n->lock); */
1319static void neigh_hh_init(struct neighbour *n)
1320{
1321 struct net_device *dev = n->dev;
1322 __be16 prot = n->tbl->protocol;
1323 struct hh_cache *hh = &n->hh;
1324
1325 write_lock_bh(&n->lock);
1326
1327 /* Only one thread can come in here and initialize the
1328 * hh_cache entry.
1329 */
1330 if (!hh->hh_len)
1331 dev->header_ops->cache(n, hh, prot);
1332
1333 write_unlock_bh(&n->lock);
1334}
1335
1336/* Slow and careful. */
1337
1338int neigh_resolve_output(struct neighbour *neigh, struct sk_buff *skb)
1339{
1340 int rc = 0;
1341
1342 if (!neigh_event_send(neigh, skb)) {
1343 int err;
1344 struct net_device *dev = neigh->dev;
1345 unsigned int seq;
1346
1347 if (dev->header_ops->cache && !neigh->hh.hh_len)
1348 neigh_hh_init(neigh);
1349
1350 do {
1351 __skb_pull(skb, skb_network_offset(skb));
1352 seq = read_seqbegin(&neigh->ha_lock);
1353 err = dev_hard_header(skb, dev, ntohs(skb->protocol),
1354 neigh->ha, NULL, skb->len);
1355 } while (read_seqretry(&neigh->ha_lock, seq));
1356
1357 if (err >= 0)
1358 rc = dev_queue_xmit(skb);
1359 else
1360 goto out_kfree_skb;
1361 }
1362out:
1363 return rc;
1364out_kfree_skb:
1365 rc = -EINVAL;
1366 kfree_skb(skb);
1367 goto out;
1368}
1369EXPORT_SYMBOL(neigh_resolve_output);
1370
1371/* As fast as possible without hh cache */
1372
1373int neigh_connected_output(struct neighbour *neigh, struct sk_buff *skb)
1374{
1375 struct net_device *dev = neigh->dev;
1376 unsigned int seq;
1377 int err;
1378
1379 do {
1380 __skb_pull(skb, skb_network_offset(skb));
1381 seq = read_seqbegin(&neigh->ha_lock);
1382 err = dev_hard_header(skb, dev, ntohs(skb->protocol),
1383 neigh->ha, NULL, skb->len);
1384 } while (read_seqretry(&neigh->ha_lock, seq));
1385
1386 if (err >= 0)
1387 err = dev_queue_xmit(skb);
1388 else {
1389 err = -EINVAL;
1390 kfree_skb(skb);
1391 }
1392 return err;
1393}
1394EXPORT_SYMBOL(neigh_connected_output);
1395
1396int neigh_direct_output(struct neighbour *neigh, struct sk_buff *skb)
1397{
1398 return dev_queue_xmit(skb);
1399}
1400EXPORT_SYMBOL(neigh_direct_output);
1401
1402static void neigh_proxy_process(struct timer_list *t)
1403{
1404 struct neigh_table *tbl = from_timer(tbl, t, proxy_timer);
1405 long sched_next = 0;
1406 unsigned long now = jiffies;
1407 struct sk_buff *skb, *n;
1408
1409 spin_lock(&tbl->proxy_queue.lock);
1410
1411 skb_queue_walk_safe(&tbl->proxy_queue, skb, n) {
1412 long tdif = NEIGH_CB(skb)->sched_next - now;
1413
1414 if (tdif <= 0) {
1415 struct net_device *dev = skb->dev;
1416
1417 __skb_unlink(skb, &tbl->proxy_queue);
1418 if (tbl->proxy_redo && netif_running(dev)) {
1419 rcu_read_lock();
1420 tbl->proxy_redo(skb);
1421 rcu_read_unlock();
1422 } else {
1423 kfree_skb(skb);
1424 }
1425
1426 dev_put(dev);
1427 } else if (!sched_next || tdif < sched_next)
1428 sched_next = tdif;
1429 }
1430 del_timer(&tbl->proxy_timer);
1431 if (sched_next)
1432 mod_timer(&tbl->proxy_timer, jiffies + sched_next);
1433 spin_unlock(&tbl->proxy_queue.lock);
1434}
1435
1436void pneigh_enqueue(struct neigh_table *tbl, struct neigh_parms *p,
1437 struct sk_buff *skb)
1438{
1439 unsigned long now = jiffies;
1440
1441 unsigned long sched_next = now + (prandom_u32() %
1442 NEIGH_VAR(p, PROXY_DELAY));
1443
1444 if (tbl->proxy_queue.qlen > NEIGH_VAR(p, PROXY_QLEN)) {
1445 kfree_skb(skb);
1446 return;
1447 }
1448
1449 NEIGH_CB(skb)->sched_next = sched_next;
1450 NEIGH_CB(skb)->flags |= LOCALLY_ENQUEUED;
1451
1452 spin_lock(&tbl->proxy_queue.lock);
1453 if (del_timer(&tbl->proxy_timer)) {
1454 if (time_before(tbl->proxy_timer.expires, sched_next))
1455 sched_next = tbl->proxy_timer.expires;
1456 }
1457 skb_dst_drop(skb);
1458 dev_hold(skb->dev);
1459 __skb_queue_tail(&tbl->proxy_queue, skb);
1460 mod_timer(&tbl->proxy_timer, sched_next);
1461 spin_unlock(&tbl->proxy_queue.lock);
1462}
1463EXPORT_SYMBOL(pneigh_enqueue);
1464
1465static inline struct neigh_parms *lookup_neigh_parms(struct neigh_table *tbl,
1466 struct net *net, int ifindex)
1467{
1468 struct neigh_parms *p;
1469
1470 list_for_each_entry(p, &tbl->parms_list, list) {
1471 if ((p->dev && p->dev->ifindex == ifindex && net_eq(neigh_parms_net(p), net)) ||
1472 (!p->dev && !ifindex && net_eq(net, &init_net)))
1473 return p;
1474 }
1475
1476 return NULL;
1477}
1478
1479struct neigh_parms *neigh_parms_alloc(struct net_device *dev,
1480 struct neigh_table *tbl)
1481{
1482 struct neigh_parms *p;
1483 struct net *net = dev_net(dev);
1484 const struct net_device_ops *ops = dev->netdev_ops;
1485
1486 p = kmemdup(&tbl->parms, sizeof(*p), GFP_KERNEL);
1487 if (p) {
1488 p->tbl = tbl;
1489 refcount_set(&p->refcnt, 1);
1490 p->reachable_time =
1491 neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME));
1492 dev_hold(dev);
1493 p->dev = dev;
1494 write_pnet(&p->net, net);
1495 p->sysctl_table = NULL;
1496
1497 if (ops->ndo_neigh_setup && ops->ndo_neigh_setup(dev, p)) {
1498 dev_put(dev);
1499 kfree(p);
1500 return NULL;
1501 }
1502
1503 write_lock_bh(&tbl->lock);
1504 list_add(&p->list, &tbl->parms.list);
1505 write_unlock_bh(&tbl->lock);
1506
1507 neigh_parms_data_state_cleanall(p);
1508 }
1509 return p;
1510}
1511EXPORT_SYMBOL(neigh_parms_alloc);
1512
1513static void neigh_rcu_free_parms(struct rcu_head *head)
1514{
1515 struct neigh_parms *parms =
1516 container_of(head, struct neigh_parms, rcu_head);
1517
1518 neigh_parms_put(parms);
1519}
1520
1521void neigh_parms_release(struct neigh_table *tbl, struct neigh_parms *parms)
1522{
1523 if (!parms || parms == &tbl->parms)
1524 return;
1525 write_lock_bh(&tbl->lock);
1526 list_del(&parms->list);
1527 parms->dead = 1;
1528 write_unlock_bh(&tbl->lock);
1529 if (parms->dev)
1530 dev_put(parms->dev);
1531 call_rcu(&parms->rcu_head, neigh_rcu_free_parms);
1532}
1533EXPORT_SYMBOL(neigh_parms_release);
1534
1535static void neigh_parms_destroy(struct neigh_parms *parms)
1536{
1537 kfree(parms);
1538}
1539
1540static struct lock_class_key neigh_table_proxy_queue_class;
1541
1542static struct neigh_table *neigh_tables[NEIGH_NR_TABLES] __read_mostly;
1543
1544void neigh_table_init(int index, struct neigh_table *tbl)
1545{
1546 unsigned long now = jiffies;
1547 unsigned long phsize;
1548
1549 INIT_LIST_HEAD(&tbl->parms_list);
1550 list_add(&tbl->parms.list, &tbl->parms_list);
1551 write_pnet(&tbl->parms.net, &init_net);
1552 refcount_set(&tbl->parms.refcnt, 1);
1553 tbl->parms.reachable_time =
1554 neigh_rand_reach_time(NEIGH_VAR(&tbl->parms, BASE_REACHABLE_TIME));
1555
1556 tbl->stats = alloc_percpu(struct neigh_statistics);
1557 if (!tbl->stats)
1558 panic("cannot create neighbour cache statistics");
1559
1560#ifdef CONFIG_PROC_FS
1561 if (!proc_create_data(tbl->id, 0, init_net.proc_net_stat,
1562 &neigh_stat_seq_fops, tbl))
1563 panic("cannot create neighbour proc dir entry");
1564#endif
1565
1566 RCU_INIT_POINTER(tbl->nht, neigh_hash_alloc(3));
1567
1568 phsize = (PNEIGH_HASHMASK + 1) * sizeof(struct pneigh_entry *);
1569 tbl->phash_buckets = kzalloc(phsize, GFP_KERNEL);
1570
1571 if (!tbl->nht || !tbl->phash_buckets)
1572 panic("cannot allocate neighbour cache hashes");
1573
1574 if (!tbl->entry_size)
1575 tbl->entry_size = ALIGN(offsetof(struct neighbour, primary_key) +
1576 tbl->key_len, NEIGH_PRIV_ALIGN);
1577 else
1578 WARN_ON(tbl->entry_size % NEIGH_PRIV_ALIGN);
1579
1580 rwlock_init(&tbl->lock);
1581 INIT_DEFERRABLE_WORK(&tbl->gc_work, neigh_periodic_work);
1582 queue_delayed_work(system_power_efficient_wq, &tbl->gc_work,
1583 tbl->parms.reachable_time);
1584 timer_setup(&tbl->proxy_timer, neigh_proxy_process, 0);
1585 skb_queue_head_init_class(&tbl->proxy_queue,
1586 &neigh_table_proxy_queue_class);
1587
1588 tbl->last_flush = now;
1589 tbl->last_rand = now + tbl->parms.reachable_time * 20;
1590
1591 neigh_tables[index] = tbl;
1592}
1593EXPORT_SYMBOL(neigh_table_init);
1594
1595int neigh_table_clear(int index, struct neigh_table *tbl)
1596{
1597 neigh_tables[index] = NULL;
1598 /* It is not clean... Fix it to unload IPv6 module safely */
1599 cancel_delayed_work_sync(&tbl->gc_work);
1600 del_timer_sync(&tbl->proxy_timer);
1601 pneigh_queue_purge(&tbl->proxy_queue);
1602 neigh_ifdown(tbl, NULL);
1603 if (atomic_read(&tbl->entries))
1604 pr_crit("neighbour leakage\n");
1605
1606 call_rcu(&rcu_dereference_protected(tbl->nht, 1)->rcu,
1607 neigh_hash_free_rcu);
1608 tbl->nht = NULL;
1609
1610 kfree(tbl->phash_buckets);
1611 tbl->phash_buckets = NULL;
1612
1613 remove_proc_entry(tbl->id, init_net.proc_net_stat);
1614
1615 free_percpu(tbl->stats);
1616 tbl->stats = NULL;
1617
1618 return 0;
1619}
1620EXPORT_SYMBOL(neigh_table_clear);
1621
1622static struct neigh_table *neigh_find_table(int family)
1623{
1624 struct neigh_table *tbl = NULL;
1625
1626 switch (family) {
1627 case AF_INET:
1628 tbl = neigh_tables[NEIGH_ARP_TABLE];
1629 break;
1630 case AF_INET6:
1631 tbl = neigh_tables[NEIGH_ND_TABLE];
1632 break;
1633 case AF_DECnet:
1634 tbl = neigh_tables[NEIGH_DN_TABLE];
1635 break;
1636 }
1637
1638 return tbl;
1639}
1640
1641static int neigh_delete(struct sk_buff *skb, struct nlmsghdr *nlh,
1642 struct netlink_ext_ack *extack)
1643{
1644 struct net *net = sock_net(skb->sk);
1645 struct ndmsg *ndm;
1646 struct nlattr *dst_attr;
1647 struct neigh_table *tbl;
1648 struct neighbour *neigh;
1649 struct net_device *dev = NULL;
1650 int err = -EINVAL;
1651
1652 ASSERT_RTNL();
1653 if (nlmsg_len(nlh) < sizeof(*ndm))
1654 goto out;
1655
1656 dst_attr = nlmsg_find_attr(nlh, sizeof(*ndm), NDA_DST);
1657 if (dst_attr == NULL)
1658 goto out;
1659
1660 ndm = nlmsg_data(nlh);
1661 if (ndm->ndm_ifindex) {
1662 dev = __dev_get_by_index(net, ndm->ndm_ifindex);
1663 if (dev == NULL) {
1664 err = -ENODEV;
1665 goto out;
1666 }
1667 }
1668
1669 tbl = neigh_find_table(ndm->ndm_family);
1670 if (tbl == NULL)
1671 return -EAFNOSUPPORT;
1672
1673 if (nla_len(dst_attr) < (int)tbl->key_len)
1674 goto out;
1675
1676 if (ndm->ndm_flags & NTF_PROXY) {
1677 err = pneigh_delete(tbl, net, nla_data(dst_attr), dev);
1678 goto out;
1679 }
1680
1681 if (dev == NULL)
1682 goto out;
1683
1684 neigh = neigh_lookup(tbl, nla_data(dst_attr), dev);
1685 if (neigh == NULL) {
1686 err = -ENOENT;
1687 goto out;
1688 }
1689
1690 err = neigh_update(neigh, NULL, NUD_FAILED,
1691 NEIGH_UPDATE_F_OVERRIDE |
1692 NEIGH_UPDATE_F_ADMIN,
1693 NETLINK_CB(skb).portid);
1694 write_lock_bh(&tbl->lock);
1695 neigh_release(neigh);
1696 neigh_remove_one(neigh, tbl);
1697 write_unlock_bh(&tbl->lock);
1698
1699out:
1700 return err;
1701}
1702
1703static int neigh_add(struct sk_buff *skb, struct nlmsghdr *nlh,
1704 struct netlink_ext_ack *extack)
1705{
1706 int flags = NEIGH_UPDATE_F_ADMIN | NEIGH_UPDATE_F_OVERRIDE;
1707 struct net *net = sock_net(skb->sk);
1708 struct ndmsg *ndm;
1709 struct nlattr *tb[NDA_MAX+1];
1710 struct neigh_table *tbl;
1711 struct net_device *dev = NULL;
1712 struct neighbour *neigh;
1713 void *dst, *lladdr;
1714 int err;
1715
1716 ASSERT_RTNL();
1717 err = nlmsg_parse(nlh, sizeof(*ndm), tb, NDA_MAX, NULL, extack);
1718 if (err < 0)
1719 goto out;
1720
1721 err = -EINVAL;
1722 if (tb[NDA_DST] == NULL)
1723 goto out;
1724
1725 ndm = nlmsg_data(nlh);
1726 if (ndm->ndm_ifindex) {
1727 dev = __dev_get_by_index(net, ndm->ndm_ifindex);
1728 if (dev == NULL) {
1729 err = -ENODEV;
1730 goto out;
1731 }
1732
1733 if (tb[NDA_LLADDR] && nla_len(tb[NDA_LLADDR]) < dev->addr_len)
1734 goto out;
1735 }
1736
1737 tbl = neigh_find_table(ndm->ndm_family);
1738 if (tbl == NULL)
1739 return -EAFNOSUPPORT;
1740
1741 if (nla_len(tb[NDA_DST]) < (int)tbl->key_len)
1742 goto out;
1743 dst = nla_data(tb[NDA_DST]);
1744 lladdr = tb[NDA_LLADDR] ? nla_data(tb[NDA_LLADDR]) : NULL;
1745
1746 if (ndm->ndm_flags & NTF_PROXY) {
1747 struct pneigh_entry *pn;
1748
1749 err = -ENOBUFS;
1750 pn = pneigh_lookup(tbl, net, dst, dev, 1);
1751 if (pn) {
1752 pn->flags = ndm->ndm_flags;
1753 err = 0;
1754 }
1755 goto out;
1756 }
1757
1758 if (dev == NULL)
1759 goto out;
1760
1761 neigh = neigh_lookup(tbl, dst, dev);
1762 if (neigh == NULL) {
1763 if (!(nlh->nlmsg_flags & NLM_F_CREATE)) {
1764 err = -ENOENT;
1765 goto out;
1766 }
1767
1768 neigh = __neigh_lookup_errno(tbl, dst, dev);
1769 if (IS_ERR(neigh)) {
1770 err = PTR_ERR(neigh);
1771 goto out;
1772 }
1773 } else {
1774 if (nlh->nlmsg_flags & NLM_F_EXCL) {
1775 err = -EEXIST;
1776 neigh_release(neigh);
1777 goto out;
1778 }
1779
1780 if (!(nlh->nlmsg_flags & NLM_F_REPLACE))
1781 flags &= ~NEIGH_UPDATE_F_OVERRIDE;
1782 }
1783
1784 if (ndm->ndm_flags & NTF_USE) {
1785 neigh_event_send(neigh, NULL);
1786 err = 0;
1787 } else
1788 err = neigh_update(neigh, lladdr, ndm->ndm_state, flags,
1789 NETLINK_CB(skb).portid);
1790 neigh_release(neigh);
1791
1792out:
1793 return err;
1794}
1795
1796static int neightbl_fill_parms(struct sk_buff *skb, struct neigh_parms *parms)
1797{
1798 struct nlattr *nest;
1799
1800 nest = nla_nest_start(skb, NDTA_PARMS);
1801 if (nest == NULL)
1802 return -ENOBUFS;
1803
1804 if ((parms->dev &&
1805 nla_put_u32(skb, NDTPA_IFINDEX, parms->dev->ifindex)) ||
1806 nla_put_u32(skb, NDTPA_REFCNT, refcount_read(&parms->refcnt)) ||
1807 nla_put_u32(skb, NDTPA_QUEUE_LENBYTES,
1808 NEIGH_VAR(parms, QUEUE_LEN_BYTES)) ||
1809 /* approximative value for deprecated QUEUE_LEN (in packets) */
1810 nla_put_u32(skb, NDTPA_QUEUE_LEN,
1811 NEIGH_VAR(parms, QUEUE_LEN_BYTES) / SKB_TRUESIZE(ETH_FRAME_LEN)) ||
1812 nla_put_u32(skb, NDTPA_PROXY_QLEN, NEIGH_VAR(parms, PROXY_QLEN)) ||
1813 nla_put_u32(skb, NDTPA_APP_PROBES, NEIGH_VAR(parms, APP_PROBES)) ||
1814 nla_put_u32(skb, NDTPA_UCAST_PROBES,
1815 NEIGH_VAR(parms, UCAST_PROBES)) ||
1816 nla_put_u32(skb, NDTPA_MCAST_PROBES,
1817 NEIGH_VAR(parms, MCAST_PROBES)) ||
1818 nla_put_u32(skb, NDTPA_MCAST_REPROBES,
1819 NEIGH_VAR(parms, MCAST_REPROBES)) ||
1820 nla_put_msecs(skb, NDTPA_REACHABLE_TIME, parms->reachable_time,
1821 NDTPA_PAD) ||
1822 nla_put_msecs(skb, NDTPA_BASE_REACHABLE_TIME,
1823 NEIGH_VAR(parms, BASE_REACHABLE_TIME), NDTPA_PAD) ||
1824 nla_put_msecs(skb, NDTPA_GC_STALETIME,
1825 NEIGH_VAR(parms, GC_STALETIME), NDTPA_PAD) ||
1826 nla_put_msecs(skb, NDTPA_DELAY_PROBE_TIME,
1827 NEIGH_VAR(parms, DELAY_PROBE_TIME), NDTPA_PAD) ||
1828 nla_put_msecs(skb, NDTPA_RETRANS_TIME,
1829 NEIGH_VAR(parms, RETRANS_TIME), NDTPA_PAD) ||
1830 nla_put_msecs(skb, NDTPA_ANYCAST_DELAY,
1831 NEIGH_VAR(parms, ANYCAST_DELAY), NDTPA_PAD) ||
1832 nla_put_msecs(skb, NDTPA_PROXY_DELAY,
1833 NEIGH_VAR(parms, PROXY_DELAY), NDTPA_PAD) ||
1834 nla_put_msecs(skb, NDTPA_LOCKTIME,
1835 NEIGH_VAR(parms, LOCKTIME), NDTPA_PAD))
1836 goto nla_put_failure;
1837 return nla_nest_end(skb, nest);
1838
1839nla_put_failure:
1840 nla_nest_cancel(skb, nest);
1841 return -EMSGSIZE;
1842}
1843
1844static int neightbl_fill_info(struct sk_buff *skb, struct neigh_table *tbl,
1845 u32 pid, u32 seq, int type, int flags)
1846{
1847 struct nlmsghdr *nlh;
1848 struct ndtmsg *ndtmsg;
1849
1850 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndtmsg), flags);
1851 if (nlh == NULL)
1852 return -EMSGSIZE;
1853
1854 ndtmsg = nlmsg_data(nlh);
1855
1856 read_lock_bh(&tbl->lock);
1857 ndtmsg->ndtm_family = tbl->family;
1858 ndtmsg->ndtm_pad1 = 0;
1859 ndtmsg->ndtm_pad2 = 0;
1860
1861 if (nla_put_string(skb, NDTA_NAME, tbl->id) ||
1862 nla_put_msecs(skb, NDTA_GC_INTERVAL, tbl->gc_interval, NDTA_PAD) ||
1863 nla_put_u32(skb, NDTA_THRESH1, tbl->gc_thresh1) ||
1864 nla_put_u32(skb, NDTA_THRESH2, tbl->gc_thresh2) ||
1865 nla_put_u32(skb, NDTA_THRESH3, tbl->gc_thresh3))
1866 goto nla_put_failure;
1867 {
1868 unsigned long now = jiffies;
1869 unsigned int flush_delta = now - tbl->last_flush;
1870 unsigned int rand_delta = now - tbl->last_rand;
1871 struct neigh_hash_table *nht;
1872 struct ndt_config ndc = {
1873 .ndtc_key_len = tbl->key_len,
1874 .ndtc_entry_size = tbl->entry_size,
1875 .ndtc_entries = atomic_read(&tbl->entries),
1876 .ndtc_last_flush = jiffies_to_msecs(flush_delta),
1877 .ndtc_last_rand = jiffies_to_msecs(rand_delta),
1878 .ndtc_proxy_qlen = tbl->proxy_queue.qlen,
1879 };
1880
1881 rcu_read_lock_bh();
1882 nht = rcu_dereference_bh(tbl->nht);
1883 ndc.ndtc_hash_rnd = nht->hash_rnd[0];
1884 ndc.ndtc_hash_mask = ((1 << nht->hash_shift) - 1);
1885 rcu_read_unlock_bh();
1886
1887 if (nla_put(skb, NDTA_CONFIG, sizeof(ndc), &ndc))
1888 goto nla_put_failure;
1889 }
1890
1891 {
1892 int cpu;
1893 struct ndt_stats ndst;
1894
1895 memset(&ndst, 0, sizeof(ndst));
1896
1897 for_each_possible_cpu(cpu) {
1898 struct neigh_statistics *st;
1899
1900 st = per_cpu_ptr(tbl->stats, cpu);
1901 ndst.ndts_allocs += st->allocs;
1902 ndst.ndts_destroys += st->destroys;
1903 ndst.ndts_hash_grows += st->hash_grows;
1904 ndst.ndts_res_failed += st->res_failed;
1905 ndst.ndts_lookups += st->lookups;
1906 ndst.ndts_hits += st->hits;
1907 ndst.ndts_rcv_probes_mcast += st->rcv_probes_mcast;
1908 ndst.ndts_rcv_probes_ucast += st->rcv_probes_ucast;
1909 ndst.ndts_periodic_gc_runs += st->periodic_gc_runs;
1910 ndst.ndts_forced_gc_runs += st->forced_gc_runs;
1911 ndst.ndts_table_fulls += st->table_fulls;
1912 }
1913
1914 if (nla_put_64bit(skb, NDTA_STATS, sizeof(ndst), &ndst,
1915 NDTA_PAD))
1916 goto nla_put_failure;
1917 }
1918
1919 BUG_ON(tbl->parms.dev);
1920 if (neightbl_fill_parms(skb, &tbl->parms) < 0)
1921 goto nla_put_failure;
1922
1923 read_unlock_bh(&tbl->lock);
1924 nlmsg_end(skb, nlh);
1925 return 0;
1926
1927nla_put_failure:
1928 read_unlock_bh(&tbl->lock);
1929 nlmsg_cancel(skb, nlh);
1930 return -EMSGSIZE;
1931}
1932
1933static int neightbl_fill_param_info(struct sk_buff *skb,
1934 struct neigh_table *tbl,
1935 struct neigh_parms *parms,
1936 u32 pid, u32 seq, int type,
1937 unsigned int flags)
1938{
1939 struct ndtmsg *ndtmsg;
1940 struct nlmsghdr *nlh;
1941
1942 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndtmsg), flags);
1943 if (nlh == NULL)
1944 return -EMSGSIZE;
1945
1946 ndtmsg = nlmsg_data(nlh);
1947
1948 read_lock_bh(&tbl->lock);
1949 ndtmsg->ndtm_family = tbl->family;
1950 ndtmsg->ndtm_pad1 = 0;
1951 ndtmsg->ndtm_pad2 = 0;
1952
1953 if (nla_put_string(skb, NDTA_NAME, tbl->id) < 0 ||
1954 neightbl_fill_parms(skb, parms) < 0)
1955 goto errout;
1956
1957 read_unlock_bh(&tbl->lock);
1958 nlmsg_end(skb, nlh);
1959 return 0;
1960errout:
1961 read_unlock_bh(&tbl->lock);
1962 nlmsg_cancel(skb, nlh);
1963 return -EMSGSIZE;
1964}
1965
1966static const struct nla_policy nl_neightbl_policy[NDTA_MAX+1] = {
1967 [NDTA_NAME] = { .type = NLA_STRING },
1968 [NDTA_THRESH1] = { .type = NLA_U32 },
1969 [NDTA_THRESH2] = { .type = NLA_U32 },
1970 [NDTA_THRESH3] = { .type = NLA_U32 },
1971 [NDTA_GC_INTERVAL] = { .type = NLA_U64 },
1972 [NDTA_PARMS] = { .type = NLA_NESTED },
1973};
1974
1975static const struct nla_policy nl_ntbl_parm_policy[NDTPA_MAX+1] = {
1976 [NDTPA_IFINDEX] = { .type = NLA_U32 },
1977 [NDTPA_QUEUE_LEN] = { .type = NLA_U32 },
1978 [NDTPA_PROXY_QLEN] = { .type = NLA_U32 },
1979 [NDTPA_APP_PROBES] = { .type = NLA_U32 },
1980 [NDTPA_UCAST_PROBES] = { .type = NLA_U32 },
1981 [NDTPA_MCAST_PROBES] = { .type = NLA_U32 },
1982 [NDTPA_MCAST_REPROBES] = { .type = NLA_U32 },
1983 [NDTPA_BASE_REACHABLE_TIME] = { .type = NLA_U64 },
1984 [NDTPA_GC_STALETIME] = { .type = NLA_U64 },
1985 [NDTPA_DELAY_PROBE_TIME] = { .type = NLA_U64 },
1986 [NDTPA_RETRANS_TIME] = { .type = NLA_U64 },
1987 [NDTPA_ANYCAST_DELAY] = { .type = NLA_U64 },
1988 [NDTPA_PROXY_DELAY] = { .type = NLA_U64 },
1989 [NDTPA_LOCKTIME] = { .type = NLA_U64 },
1990};
1991
1992static int neightbl_set(struct sk_buff *skb, struct nlmsghdr *nlh,
1993 struct netlink_ext_ack *extack)
1994{
1995 struct net *net = sock_net(skb->sk);
1996 struct neigh_table *tbl;
1997 struct ndtmsg *ndtmsg;
1998 struct nlattr *tb[NDTA_MAX+1];
1999 bool found = false;
2000 int err, tidx;
2001
2002 err = nlmsg_parse(nlh, sizeof(*ndtmsg), tb, NDTA_MAX,
2003 nl_neightbl_policy, extack);
2004 if (err < 0)
2005 goto errout;
2006
2007 if (tb[NDTA_NAME] == NULL) {
2008 err = -EINVAL;
2009 goto errout;
2010 }
2011
2012 ndtmsg = nlmsg_data(nlh);
2013
2014 for (tidx = 0; tidx < NEIGH_NR_TABLES; tidx++) {
2015 tbl = neigh_tables[tidx];
2016 if (!tbl)
2017 continue;
2018 if (ndtmsg->ndtm_family && tbl->family != ndtmsg->ndtm_family)
2019 continue;
2020 if (nla_strcmp(tb[NDTA_NAME], tbl->id) == 0) {
2021 found = true;
2022 break;
2023 }
2024 }
2025
2026 if (!found)
2027 return -ENOENT;
2028
2029 /*
2030 * We acquire tbl->lock to be nice to the periodic timers and
2031 * make sure they always see a consistent set of values.
2032 */
2033 write_lock_bh(&tbl->lock);
2034
2035 if (tb[NDTA_PARMS]) {
2036 struct nlattr *tbp[NDTPA_MAX+1];
2037 struct neigh_parms *p;
2038 int i, ifindex = 0;
2039
2040 err = nla_parse_nested(tbp, NDTPA_MAX, tb[NDTA_PARMS],
2041 nl_ntbl_parm_policy, extack);
2042 if (err < 0)
2043 goto errout_tbl_lock;
2044
2045 if (tbp[NDTPA_IFINDEX])
2046 ifindex = nla_get_u32(tbp[NDTPA_IFINDEX]);
2047
2048 p = lookup_neigh_parms(tbl, net, ifindex);
2049 if (p == NULL) {
2050 err = -ENOENT;
2051 goto errout_tbl_lock;
2052 }
2053
2054 for (i = 1; i <= NDTPA_MAX; i++) {
2055 if (tbp[i] == NULL)
2056 continue;
2057
2058 switch (i) {
2059 case NDTPA_QUEUE_LEN:
2060 NEIGH_VAR_SET(p, QUEUE_LEN_BYTES,
2061 nla_get_u32(tbp[i]) *
2062 SKB_TRUESIZE(ETH_FRAME_LEN));
2063 break;
2064 case NDTPA_QUEUE_LENBYTES:
2065 NEIGH_VAR_SET(p, QUEUE_LEN_BYTES,
2066 nla_get_u32(tbp[i]));
2067 break;
2068 case NDTPA_PROXY_QLEN:
2069 NEIGH_VAR_SET(p, PROXY_QLEN,
2070 nla_get_u32(tbp[i]));
2071 break;
2072 case NDTPA_APP_PROBES:
2073 NEIGH_VAR_SET(p, APP_PROBES,
2074 nla_get_u32(tbp[i]));
2075 break;
2076 case NDTPA_UCAST_PROBES:
2077 NEIGH_VAR_SET(p, UCAST_PROBES,
2078 nla_get_u32(tbp[i]));
2079 break;
2080 case NDTPA_MCAST_PROBES:
2081 NEIGH_VAR_SET(p, MCAST_PROBES,
2082 nla_get_u32(tbp[i]));
2083 break;
2084 case NDTPA_MCAST_REPROBES:
2085 NEIGH_VAR_SET(p, MCAST_REPROBES,
2086 nla_get_u32(tbp[i]));
2087 break;
2088 case NDTPA_BASE_REACHABLE_TIME:
2089 NEIGH_VAR_SET(p, BASE_REACHABLE_TIME,
2090 nla_get_msecs(tbp[i]));
2091 /* update reachable_time as well, otherwise, the change will
2092 * only be effective after the next time neigh_periodic_work
2093 * decides to recompute it (can be multiple minutes)
2094 */
2095 p->reachable_time =
2096 neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME));
2097 break;
2098 case NDTPA_GC_STALETIME:
2099 NEIGH_VAR_SET(p, GC_STALETIME,
2100 nla_get_msecs(tbp[i]));
2101 break;
2102 case NDTPA_DELAY_PROBE_TIME:
2103 NEIGH_VAR_SET(p, DELAY_PROBE_TIME,
2104 nla_get_msecs(tbp[i]));
2105 call_netevent_notifiers(NETEVENT_DELAY_PROBE_TIME_UPDATE, p);
2106 break;
2107 case NDTPA_RETRANS_TIME:
2108 NEIGH_VAR_SET(p, RETRANS_TIME,
2109 nla_get_msecs(tbp[i]));
2110 break;
2111 case NDTPA_ANYCAST_DELAY:
2112 NEIGH_VAR_SET(p, ANYCAST_DELAY,
2113 nla_get_msecs(tbp[i]));
2114 break;
2115 case NDTPA_PROXY_DELAY:
2116 NEIGH_VAR_SET(p, PROXY_DELAY,
2117 nla_get_msecs(tbp[i]));
2118 break;
2119 case NDTPA_LOCKTIME:
2120 NEIGH_VAR_SET(p, LOCKTIME,
2121 nla_get_msecs(tbp[i]));
2122 break;
2123 }
2124 }
2125 }
2126
2127 err = -ENOENT;
2128 if ((tb[NDTA_THRESH1] || tb[NDTA_THRESH2] ||
2129 tb[NDTA_THRESH3] || tb[NDTA_GC_INTERVAL]) &&
2130 !net_eq(net, &init_net))
2131 goto errout_tbl_lock;
2132
2133 if (tb[NDTA_THRESH1])
2134 tbl->gc_thresh1 = nla_get_u32(tb[NDTA_THRESH1]);
2135
2136 if (tb[NDTA_THRESH2])
2137 tbl->gc_thresh2 = nla_get_u32(tb[NDTA_THRESH2]);
2138
2139 if (tb[NDTA_THRESH3])
2140 tbl->gc_thresh3 = nla_get_u32(tb[NDTA_THRESH3]);
2141
2142 if (tb[NDTA_GC_INTERVAL])
2143 tbl->gc_interval = nla_get_msecs(tb[NDTA_GC_INTERVAL]);
2144
2145 err = 0;
2146
2147errout_tbl_lock:
2148 write_unlock_bh(&tbl->lock);
2149errout:
2150 return err;
2151}
2152
2153static int neightbl_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
2154{
2155 struct net *net = sock_net(skb->sk);
2156 int family, tidx, nidx = 0;
2157 int tbl_skip = cb->args[0];
2158 int neigh_skip = cb->args[1];
2159 struct neigh_table *tbl;
2160
2161 family = ((struct rtgenmsg *) nlmsg_data(cb->nlh))->rtgen_family;
2162
2163 for (tidx = 0; tidx < NEIGH_NR_TABLES; tidx++) {
2164 struct neigh_parms *p;
2165
2166 tbl = neigh_tables[tidx];
2167 if (!tbl)
2168 continue;
2169
2170 if (tidx < tbl_skip || (family && tbl->family != family))
2171 continue;
2172
2173 if (neightbl_fill_info(skb, tbl, NETLINK_CB(cb->skb).portid,
2174 cb->nlh->nlmsg_seq, RTM_NEWNEIGHTBL,
2175 NLM_F_MULTI) < 0)
2176 break;
2177
2178 nidx = 0;
2179 p = list_next_entry(&tbl->parms, list);
2180 list_for_each_entry_from(p, &tbl->parms_list, list) {
2181 if (!net_eq(neigh_parms_net(p), net))
2182 continue;
2183
2184 if (nidx < neigh_skip)
2185 goto next;
2186
2187 if (neightbl_fill_param_info(skb, tbl, p,
2188 NETLINK_CB(cb->skb).portid,
2189 cb->nlh->nlmsg_seq,
2190 RTM_NEWNEIGHTBL,
2191 NLM_F_MULTI) < 0)
2192 goto out;
2193 next:
2194 nidx++;
2195 }
2196
2197 neigh_skip = 0;
2198 }
2199out:
2200 cb->args[0] = tidx;
2201 cb->args[1] = nidx;
2202
2203 return skb->len;
2204}
2205
2206static int neigh_fill_info(struct sk_buff *skb, struct neighbour *neigh,
2207 u32 pid, u32 seq, int type, unsigned int flags)
2208{
2209 unsigned long now = jiffies;
2210 struct nda_cacheinfo ci;
2211 struct nlmsghdr *nlh;
2212 struct ndmsg *ndm;
2213
2214 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndm), flags);
2215 if (nlh == NULL)
2216 return -EMSGSIZE;
2217
2218 ndm = nlmsg_data(nlh);
2219 ndm->ndm_family = neigh->ops->family;
2220 ndm->ndm_pad1 = 0;
2221 ndm->ndm_pad2 = 0;
2222 ndm->ndm_flags = neigh->flags;
2223 ndm->ndm_type = neigh->type;
2224 ndm->ndm_ifindex = neigh->dev->ifindex;
2225
2226 if (nla_put(skb, NDA_DST, neigh->tbl->key_len, neigh->primary_key))
2227 goto nla_put_failure;
2228
2229 read_lock_bh(&neigh->lock);
2230 ndm->ndm_state = neigh->nud_state;
2231 if (neigh->nud_state & NUD_VALID) {
2232 char haddr[MAX_ADDR_LEN];
2233
2234 neigh_ha_snapshot(haddr, neigh, neigh->dev);
2235 if (nla_put(skb, NDA_LLADDR, neigh->dev->addr_len, haddr) < 0) {
2236 read_unlock_bh(&neigh->lock);
2237 goto nla_put_failure;
2238 }
2239 }
2240
2241 ci.ndm_used = jiffies_to_clock_t(now - neigh->used);
2242 ci.ndm_confirmed = jiffies_to_clock_t(now - neigh->confirmed);
2243 ci.ndm_updated = jiffies_to_clock_t(now - neigh->updated);
2244 ci.ndm_refcnt = refcount_read(&neigh->refcnt) - 1;
2245 read_unlock_bh(&neigh->lock);
2246
2247 if (nla_put_u32(skb, NDA_PROBES, atomic_read(&neigh->probes)) ||
2248 nla_put(skb, NDA_CACHEINFO, sizeof(ci), &ci))
2249 goto nla_put_failure;
2250
2251 nlmsg_end(skb, nlh);
2252 return 0;
2253
2254nla_put_failure:
2255 nlmsg_cancel(skb, nlh);
2256 return -EMSGSIZE;
2257}
2258
2259static int pneigh_fill_info(struct sk_buff *skb, struct pneigh_entry *pn,
2260 u32 pid, u32 seq, int type, unsigned int flags,
2261 struct neigh_table *tbl)
2262{
2263 struct nlmsghdr *nlh;
2264 struct ndmsg *ndm;
2265
2266 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndm), flags);
2267 if (nlh == NULL)
2268 return -EMSGSIZE;
2269
2270 ndm = nlmsg_data(nlh);
2271 ndm->ndm_family = tbl->family;
2272 ndm->ndm_pad1 = 0;
2273 ndm->ndm_pad2 = 0;
2274 ndm->ndm_flags = pn->flags | NTF_PROXY;
2275 ndm->ndm_type = RTN_UNICAST;
2276 ndm->ndm_ifindex = pn->dev ? pn->dev->ifindex : 0;
2277 ndm->ndm_state = NUD_NONE;
2278
2279 if (nla_put(skb, NDA_DST, tbl->key_len, pn->key))
2280 goto nla_put_failure;
2281
2282 nlmsg_end(skb, nlh);
2283 return 0;
2284
2285nla_put_failure:
2286 nlmsg_cancel(skb, nlh);
2287 return -EMSGSIZE;
2288}
2289
2290static void neigh_update_notify(struct neighbour *neigh, u32 nlmsg_pid)
2291{
2292 call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, neigh);
2293 __neigh_notify(neigh, RTM_NEWNEIGH, 0, nlmsg_pid);
2294}
2295
2296static bool neigh_master_filtered(struct net_device *dev, int master_idx)
2297{
2298 struct net_device *master;
2299
2300 if (!master_idx)
2301 return false;
2302
2303 master = netdev_master_upper_dev_get(dev);
2304 if (!master || master->ifindex != master_idx)
2305 return true;
2306
2307 return false;
2308}
2309
2310static bool neigh_ifindex_filtered(struct net_device *dev, int filter_idx)
2311{
2312 if (filter_idx && dev->ifindex != filter_idx)
2313 return true;
2314
2315 return false;
2316}
2317
2318static int neigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb,
2319 struct netlink_callback *cb)
2320{
2321 struct net *net = sock_net(skb->sk);
2322 const struct nlmsghdr *nlh = cb->nlh;
2323 struct nlattr *tb[NDA_MAX + 1];
2324 struct neighbour *n;
2325 int rc, h, s_h = cb->args[1];
2326 int idx, s_idx = idx = cb->args[2];
2327 struct neigh_hash_table *nht;
2328 int filter_master_idx = 0, filter_idx = 0;
2329 unsigned int flags = NLM_F_MULTI;
2330 int err;
2331
2332 err = nlmsg_parse(nlh, sizeof(struct ndmsg), tb, NDA_MAX, NULL, NULL);
2333 if (!err) {
2334 if (tb[NDA_IFINDEX]) {
2335 if (nla_len(tb[NDA_IFINDEX]) != sizeof(u32))
2336 return -EINVAL;
2337 filter_idx = nla_get_u32(tb[NDA_IFINDEX]);
2338 }
2339 if (tb[NDA_MASTER]) {
2340 if (nla_len(tb[NDA_MASTER]) != sizeof(u32))
2341 return -EINVAL;
2342 filter_master_idx = nla_get_u32(tb[NDA_MASTER]);
2343 }
2344 if (filter_idx || filter_master_idx)
2345 flags |= NLM_F_DUMP_FILTERED;
2346 }
2347
2348 rcu_read_lock_bh();
2349 nht = rcu_dereference_bh(tbl->nht);
2350
2351 for (h = s_h; h < (1 << nht->hash_shift); h++) {
2352 if (h > s_h)
2353 s_idx = 0;
2354 for (n = rcu_dereference_bh(nht->hash_buckets[h]), idx = 0;
2355 n != NULL;
2356 n = rcu_dereference_bh(n->next)) {
2357 if (idx < s_idx || !net_eq(dev_net(n->dev), net))
2358 goto next;
2359 if (neigh_ifindex_filtered(n->dev, filter_idx) ||
2360 neigh_master_filtered(n->dev, filter_master_idx))
2361 goto next;
2362 if (neigh_fill_info(skb, n, NETLINK_CB(cb->skb).portid,
2363 cb->nlh->nlmsg_seq,
2364 RTM_NEWNEIGH,
2365 flags) < 0) {
2366 rc = -1;
2367 goto out;
2368 }
2369next:
2370 idx++;
2371 }
2372 }
2373 rc = skb->len;
2374out:
2375 rcu_read_unlock_bh();
2376 cb->args[1] = h;
2377 cb->args[2] = idx;
2378 return rc;
2379}
2380
2381static int pneigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb,
2382 struct netlink_callback *cb)
2383{
2384 struct pneigh_entry *n;
2385 struct net *net = sock_net(skb->sk);
2386 int rc, h, s_h = cb->args[3];
2387 int idx, s_idx = idx = cb->args[4];
2388
2389 read_lock_bh(&tbl->lock);
2390
2391 for (h = s_h; h <= PNEIGH_HASHMASK; h++) {
2392 if (h > s_h)
2393 s_idx = 0;
2394 for (n = tbl->phash_buckets[h], idx = 0; n; n = n->next) {
2395 if (idx < s_idx || pneigh_net(n) != net)
2396 goto next;
2397 if (pneigh_fill_info(skb, n, NETLINK_CB(cb->skb).portid,
2398 cb->nlh->nlmsg_seq,
2399 RTM_NEWNEIGH,
2400 NLM_F_MULTI, tbl) < 0) {
2401 read_unlock_bh(&tbl->lock);
2402 rc = -1;
2403 goto out;
2404 }
2405 next:
2406 idx++;
2407 }
2408 }
2409
2410 read_unlock_bh(&tbl->lock);
2411 rc = skb->len;
2412out:
2413 cb->args[3] = h;
2414 cb->args[4] = idx;
2415 return rc;
2416
2417}
2418
2419static int neigh_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
2420{
2421 struct neigh_table *tbl;
2422 int t, family, s_t;
2423 int proxy = 0;
2424 int err;
2425
2426 family = ((struct rtgenmsg *) nlmsg_data(cb->nlh))->rtgen_family;
2427
2428 /* check for full ndmsg structure presence, family member is
2429 * the same for both structures
2430 */
2431 if (nlmsg_len(cb->nlh) >= sizeof(struct ndmsg) &&
2432 ((struct ndmsg *) nlmsg_data(cb->nlh))->ndm_flags == NTF_PROXY)
2433 proxy = 1;
2434
2435 s_t = cb->args[0];
2436
2437 for (t = 0; t < NEIGH_NR_TABLES; t++) {
2438 tbl = neigh_tables[t];
2439
2440 if (!tbl)
2441 continue;
2442 if (t < s_t || (family && tbl->family != family))
2443 continue;
2444 if (t > s_t)
2445 memset(&cb->args[1], 0, sizeof(cb->args) -
2446 sizeof(cb->args[0]));
2447 if (proxy)
2448 err = pneigh_dump_table(tbl, skb, cb);
2449 else
2450 err = neigh_dump_table(tbl, skb, cb);
2451 if (err < 0)
2452 break;
2453 }
2454
2455 cb->args[0] = t;
2456 return skb->len;
2457}
2458
2459void neigh_for_each(struct neigh_table *tbl, void (*cb)(struct neighbour *, void *), void *cookie)
2460{
2461 int chain;
2462 struct neigh_hash_table *nht;
2463
2464 rcu_read_lock_bh();
2465 nht = rcu_dereference_bh(tbl->nht);
2466
2467 read_lock(&tbl->lock); /* avoid resizes */
2468 for (chain = 0; chain < (1 << nht->hash_shift); chain++) {
2469 struct neighbour *n;
2470
2471 for (n = rcu_dereference_bh(nht->hash_buckets[chain]);
2472 n != NULL;
2473 n = rcu_dereference_bh(n->next))
2474 cb(n, cookie);
2475 }
2476 read_unlock(&tbl->lock);
2477 rcu_read_unlock_bh();
2478}
2479EXPORT_SYMBOL(neigh_for_each);
2480
2481/* The tbl->lock must be held as a writer and BH disabled. */
2482void __neigh_for_each_release(struct neigh_table *tbl,
2483 int (*cb)(struct neighbour *))
2484{
2485 int chain;
2486 struct neigh_hash_table *nht;
2487
2488 nht = rcu_dereference_protected(tbl->nht,
2489 lockdep_is_held(&tbl->lock));
2490 for (chain = 0; chain < (1 << nht->hash_shift); chain++) {
2491 struct neighbour *n;
2492 struct neighbour __rcu **np;
2493
2494 np = &nht->hash_buckets[chain];
2495 while ((n = rcu_dereference_protected(*np,
2496 lockdep_is_held(&tbl->lock))) != NULL) {
2497 int release;
2498
2499 write_lock(&n->lock);
2500 release = cb(n);
2501 if (release) {
2502 rcu_assign_pointer(*np,
2503 rcu_dereference_protected(n->next,
2504 lockdep_is_held(&tbl->lock)));
2505 n->dead = 1;
2506 } else
2507 np = &n->next;
2508 write_unlock(&n->lock);
2509 if (release)
2510 neigh_cleanup_and_release(n);
2511 }
2512 }
2513}
2514EXPORT_SYMBOL(__neigh_for_each_release);
2515
2516int neigh_xmit(int index, struct net_device *dev,
2517 const void *addr, struct sk_buff *skb)
2518{
2519 int err = -EAFNOSUPPORT;
2520 if (likely(index < NEIGH_NR_TABLES)) {
2521 struct neigh_table *tbl;
2522 struct neighbour *neigh;
2523
2524 tbl = neigh_tables[index];
2525 if (!tbl)
2526 goto out;
2527 rcu_read_lock_bh();
2528 neigh = __neigh_lookup_noref(tbl, addr, dev);
2529 if (!neigh)
2530 neigh = __neigh_create(tbl, addr, dev, false);
2531 err = PTR_ERR(neigh);
2532 if (IS_ERR(neigh)) {
2533 rcu_read_unlock_bh();
2534 goto out_kfree_skb;
2535 }
2536 err = neigh->output(neigh, skb);
2537 rcu_read_unlock_bh();
2538 }
2539 else if (index == NEIGH_LINK_TABLE) {
2540 err = dev_hard_header(skb, dev, ntohs(skb->protocol),
2541 addr, NULL, skb->len);
2542 if (err < 0)
2543 goto out_kfree_skb;
2544 err = dev_queue_xmit(skb);
2545 }
2546out:
2547 return err;
2548out_kfree_skb:
2549 kfree_skb(skb);
2550 goto out;
2551}
2552EXPORT_SYMBOL(neigh_xmit);
2553
2554#ifdef CONFIG_PROC_FS
2555
2556static struct neighbour *neigh_get_first(struct seq_file *seq)
2557{
2558 struct neigh_seq_state *state = seq->private;
2559 struct net *net = seq_file_net(seq);
2560 struct neigh_hash_table *nht = state->nht;
2561 struct neighbour *n = NULL;
2562 int bucket = state->bucket;
2563
2564 state->flags &= ~NEIGH_SEQ_IS_PNEIGH;
2565 for (bucket = 0; bucket < (1 << nht->hash_shift); bucket++) {
2566 n = rcu_dereference_bh(nht->hash_buckets[bucket]);
2567
2568 while (n) {
2569 if (!net_eq(dev_net(n->dev), net))
2570 goto next;
2571 if (state->neigh_sub_iter) {
2572 loff_t fakep = 0;
2573 void *v;
2574
2575 v = state->neigh_sub_iter(state, n, &fakep);
2576 if (!v)
2577 goto next;
2578 }
2579 if (!(state->flags & NEIGH_SEQ_SKIP_NOARP))
2580 break;
2581 if (n->nud_state & ~NUD_NOARP)
2582 break;
2583next:
2584 n = rcu_dereference_bh(n->next);
2585 }
2586
2587 if (n)
2588 break;
2589 }
2590 state->bucket = bucket;
2591
2592 return n;
2593}
2594
2595static struct neighbour *neigh_get_next(struct seq_file *seq,
2596 struct neighbour *n,
2597 loff_t *pos)
2598{
2599 struct neigh_seq_state *state = seq->private;
2600 struct net *net = seq_file_net(seq);
2601 struct neigh_hash_table *nht = state->nht;
2602
2603 if (state->neigh_sub_iter) {
2604 void *v = state->neigh_sub_iter(state, n, pos);
2605 if (v)
2606 return n;
2607 }
2608 n = rcu_dereference_bh(n->next);
2609
2610 while (1) {
2611 while (n) {
2612 if (!net_eq(dev_net(n->dev), net))
2613 goto next;
2614 if (state->neigh_sub_iter) {
2615 void *v = state->neigh_sub_iter(state, n, pos);
2616 if (v)
2617 return n;
2618 goto next;
2619 }
2620 if (!(state->flags & NEIGH_SEQ_SKIP_NOARP))
2621 break;
2622
2623 if (n->nud_state & ~NUD_NOARP)
2624 break;
2625next:
2626 n = rcu_dereference_bh(n->next);
2627 }
2628
2629 if (n)
2630 break;
2631
2632 if (++state->bucket >= (1 << nht->hash_shift))
2633 break;
2634
2635 n = rcu_dereference_bh(nht->hash_buckets[state->bucket]);
2636 }
2637
2638 if (n && pos)
2639 --(*pos);
2640 return n;
2641}
2642
2643static struct neighbour *neigh_get_idx(struct seq_file *seq, loff_t *pos)
2644{
2645 struct neighbour *n = neigh_get_first(seq);
2646
2647 if (n) {
2648 --(*pos);
2649 while (*pos) {
2650 n = neigh_get_next(seq, n, pos);
2651 if (!n)
2652 break;
2653 }
2654 }
2655 return *pos ? NULL : n;
2656}
2657
2658static struct pneigh_entry *pneigh_get_first(struct seq_file *seq)
2659{
2660 struct neigh_seq_state *state = seq->private;
2661 struct net *net = seq_file_net(seq);
2662 struct neigh_table *tbl = state->tbl;
2663 struct pneigh_entry *pn = NULL;
2664 int bucket = state->bucket;
2665
2666 state->flags |= NEIGH_SEQ_IS_PNEIGH;
2667 for (bucket = 0; bucket <= PNEIGH_HASHMASK; bucket++) {
2668 pn = tbl->phash_buckets[bucket];
2669 while (pn && !net_eq(pneigh_net(pn), net))
2670 pn = pn->next;
2671 if (pn)
2672 break;
2673 }
2674 state->bucket = bucket;
2675
2676 return pn;
2677}
2678
2679static struct pneigh_entry *pneigh_get_next(struct seq_file *seq,
2680 struct pneigh_entry *pn,
2681 loff_t *pos)
2682{
2683 struct neigh_seq_state *state = seq->private;
2684 struct net *net = seq_file_net(seq);
2685 struct neigh_table *tbl = state->tbl;
2686
2687 do {
2688 pn = pn->next;
2689 } while (pn && !net_eq(pneigh_net(pn), net));
2690
2691 while (!pn) {
2692 if (++state->bucket > PNEIGH_HASHMASK)
2693 break;
2694 pn = tbl->phash_buckets[state->bucket];
2695 while (pn && !net_eq(pneigh_net(pn), net))
2696 pn = pn->next;
2697 if (pn)
2698 break;
2699 }
2700
2701 if (pn && pos)
2702 --(*pos);
2703
2704 return pn;
2705}
2706
2707static struct pneigh_entry *pneigh_get_idx(struct seq_file *seq, loff_t *pos)
2708{
2709 struct pneigh_entry *pn = pneigh_get_first(seq);
2710
2711 if (pn) {
2712 --(*pos);
2713 while (*pos) {
2714 pn = pneigh_get_next(seq, pn, pos);
2715 if (!pn)
2716 break;
2717 }
2718 }
2719 return *pos ? NULL : pn;
2720}
2721
2722static void *neigh_get_idx_any(struct seq_file *seq, loff_t *pos)
2723{
2724 struct neigh_seq_state *state = seq->private;
2725 void *rc;
2726 loff_t idxpos = *pos;
2727
2728 rc = neigh_get_idx(seq, &idxpos);
2729 if (!rc && !(state->flags & NEIGH_SEQ_NEIGH_ONLY))
2730 rc = pneigh_get_idx(seq, &idxpos);
2731
2732 return rc;
2733}
2734
2735void *neigh_seq_start(struct seq_file *seq, loff_t *pos, struct neigh_table *tbl, unsigned int neigh_seq_flags)
2736 __acquires(rcu_bh)
2737{
2738 struct neigh_seq_state *state = seq->private;
2739
2740 state->tbl = tbl;
2741 state->bucket = 0;
2742 state->flags = (neigh_seq_flags & ~NEIGH_SEQ_IS_PNEIGH);
2743
2744 rcu_read_lock_bh();
2745 state->nht = rcu_dereference_bh(tbl->nht);
2746
2747 return *pos ? neigh_get_idx_any(seq, pos) : SEQ_START_TOKEN;
2748}
2749EXPORT_SYMBOL(neigh_seq_start);
2750
2751void *neigh_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2752{
2753 struct neigh_seq_state *state;
2754 void *rc;
2755
2756 if (v == SEQ_START_TOKEN) {
2757 rc = neigh_get_first(seq);
2758 goto out;
2759 }
2760
2761 state = seq->private;
2762 if (!(state->flags & NEIGH_SEQ_IS_PNEIGH)) {
2763 rc = neigh_get_next(seq, v, NULL);
2764 if (rc)
2765 goto out;
2766 if (!(state->flags & NEIGH_SEQ_NEIGH_ONLY))
2767 rc = pneigh_get_first(seq);
2768 } else {
2769 BUG_ON(state->flags & NEIGH_SEQ_NEIGH_ONLY);
2770 rc = pneigh_get_next(seq, v, NULL);
2771 }
2772out:
2773 ++(*pos);
2774 return rc;
2775}
2776EXPORT_SYMBOL(neigh_seq_next);
2777
2778void neigh_seq_stop(struct seq_file *seq, void *v)
2779 __releases(rcu_bh)
2780{
2781 rcu_read_unlock_bh();
2782}
2783EXPORT_SYMBOL(neigh_seq_stop);
2784
2785/* statistics via seq_file */
2786
2787static void *neigh_stat_seq_start(struct seq_file *seq, loff_t *pos)
2788{
2789 struct neigh_table *tbl = seq->private;
2790 int cpu;
2791
2792 if (*pos == 0)
2793 return SEQ_START_TOKEN;
2794
2795 for (cpu = *pos-1; cpu < nr_cpu_ids; ++cpu) {
2796 if (!cpu_possible(cpu))
2797 continue;
2798 *pos = cpu+1;
2799 return per_cpu_ptr(tbl->stats, cpu);
2800 }
2801 return NULL;
2802}
2803
2804static void *neigh_stat_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2805{
2806 struct neigh_table *tbl = seq->private;
2807 int cpu;
2808
2809 for (cpu = *pos; cpu < nr_cpu_ids; ++cpu) {
2810 if (!cpu_possible(cpu))
2811 continue;
2812 *pos = cpu+1;
2813 return per_cpu_ptr(tbl->stats, cpu);
2814 }
2815 return NULL;
2816}
2817
2818static void neigh_stat_seq_stop(struct seq_file *seq, void *v)
2819{
2820
2821}
2822
2823static int neigh_stat_seq_show(struct seq_file *seq, void *v)
2824{
2825 struct neigh_table *tbl = seq->private;
2826 struct neigh_statistics *st = v;
2827
2828 if (v == SEQ_START_TOKEN) {
2829 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");
2830 return 0;
2831 }
2832
2833 seq_printf(seq, "%08x %08lx %08lx %08lx %08lx %08lx %08lx "
2834 "%08lx %08lx %08lx %08lx %08lx %08lx\n",
2835 atomic_read(&tbl->entries),
2836
2837 st->allocs,
2838 st->destroys,
2839 st->hash_grows,
2840
2841 st->lookups,
2842 st->hits,
2843
2844 st->res_failed,
2845
2846 st->rcv_probes_mcast,
2847 st->rcv_probes_ucast,
2848
2849 st->periodic_gc_runs,
2850 st->forced_gc_runs,
2851 st->unres_discards,
2852 st->table_fulls
2853 );
2854
2855 return 0;
2856}
2857
2858static const struct seq_operations neigh_stat_seq_ops = {
2859 .start = neigh_stat_seq_start,
2860 .next = neigh_stat_seq_next,
2861 .stop = neigh_stat_seq_stop,
2862 .show = neigh_stat_seq_show,
2863};
2864
2865static int neigh_stat_seq_open(struct inode *inode, struct file *file)
2866{
2867 int ret = seq_open(file, &neigh_stat_seq_ops);
2868
2869 if (!ret) {
2870 struct seq_file *sf = file->private_data;
2871 sf->private = PDE_DATA(inode);
2872 }
2873 return ret;
2874};
2875
2876static const struct file_operations neigh_stat_seq_fops = {
2877 .open = neigh_stat_seq_open,
2878 .read = seq_read,
2879 .llseek = seq_lseek,
2880 .release = seq_release,
2881};
2882
2883#endif /* CONFIG_PROC_FS */
2884
2885static inline size_t neigh_nlmsg_size(void)
2886{
2887 return NLMSG_ALIGN(sizeof(struct ndmsg))
2888 + nla_total_size(MAX_ADDR_LEN) /* NDA_DST */
2889 + nla_total_size(MAX_ADDR_LEN) /* NDA_LLADDR */
2890 + nla_total_size(sizeof(struct nda_cacheinfo))
2891 + nla_total_size(4); /* NDA_PROBES */
2892}
2893
2894static void __neigh_notify(struct neighbour *n, int type, int flags,
2895 u32 pid)
2896{
2897 struct net *net = dev_net(n->dev);
2898 struct sk_buff *skb;
2899 int err = -ENOBUFS;
2900
2901 skb = nlmsg_new(neigh_nlmsg_size(), GFP_ATOMIC);
2902 if (skb == NULL)
2903 goto errout;
2904
2905 err = neigh_fill_info(skb, n, pid, 0, type, flags);
2906 if (err < 0) {
2907 /* -EMSGSIZE implies BUG in neigh_nlmsg_size() */
2908 WARN_ON(err == -EMSGSIZE);
2909 kfree_skb(skb);
2910 goto errout;
2911 }
2912 rtnl_notify(skb, net, 0, RTNLGRP_NEIGH, NULL, GFP_ATOMIC);
2913 return;
2914errout:
2915 if (err < 0)
2916 rtnl_set_sk_err(net, RTNLGRP_NEIGH, err);
2917}
2918
2919void neigh_app_ns(struct neighbour *n)
2920{
2921 __neigh_notify(n, RTM_GETNEIGH, NLM_F_REQUEST, 0);
2922}
2923EXPORT_SYMBOL(neigh_app_ns);
2924
2925#ifdef CONFIG_SYSCTL
2926static int zero;
2927static int int_max = INT_MAX;
2928static int unres_qlen_max = INT_MAX / SKB_TRUESIZE(ETH_FRAME_LEN);
2929
2930static int proc_unres_qlen(struct ctl_table *ctl, int write,
2931 void __user *buffer, size_t *lenp, loff_t *ppos)
2932{
2933 int size, ret;
2934 struct ctl_table tmp = *ctl;
2935
2936 tmp.extra1 = &zero;
2937 tmp.extra2 = &unres_qlen_max;
2938 tmp.data = &size;
2939
2940 size = *(int *)ctl->data / SKB_TRUESIZE(ETH_FRAME_LEN);
2941 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
2942
2943 if (write && !ret)
2944 *(int *)ctl->data = size * SKB_TRUESIZE(ETH_FRAME_LEN);
2945 return ret;
2946}
2947
2948static struct neigh_parms *neigh_get_dev_parms_rcu(struct net_device *dev,
2949 int family)
2950{
2951 switch (family) {
2952 case AF_INET:
2953 return __in_dev_arp_parms_get_rcu(dev);
2954 case AF_INET6:
2955 return __in6_dev_nd_parms_get_rcu(dev);
2956 }
2957 return NULL;
2958}
2959
2960static void neigh_copy_dflt_parms(struct net *net, struct neigh_parms *p,
2961 int index)
2962{
2963 struct net_device *dev;
2964 int family = neigh_parms_family(p);
2965
2966 rcu_read_lock();
2967 for_each_netdev_rcu(net, dev) {
2968 struct neigh_parms *dst_p =
2969 neigh_get_dev_parms_rcu(dev, family);
2970
2971 if (dst_p && !test_bit(index, dst_p->data_state))
2972 dst_p->data[index] = p->data[index];
2973 }
2974 rcu_read_unlock();
2975}
2976
2977static void neigh_proc_update(struct ctl_table *ctl, int write)
2978{
2979 struct net_device *dev = ctl->extra1;
2980 struct neigh_parms *p = ctl->extra2;
2981 struct net *net = neigh_parms_net(p);
2982 int index = (int *) ctl->data - p->data;
2983
2984 if (!write)
2985 return;
2986
2987 set_bit(index, p->data_state);
2988 if (index == NEIGH_VAR_DELAY_PROBE_TIME)
2989 call_netevent_notifiers(NETEVENT_DELAY_PROBE_TIME_UPDATE, p);
2990 if (!dev) /* NULL dev means this is default value */
2991 neigh_copy_dflt_parms(net, p, index);
2992}
2993
2994static int neigh_proc_dointvec_zero_intmax(struct ctl_table *ctl, int write,
2995 void __user *buffer,
2996 size_t *lenp, loff_t *ppos)
2997{
2998 struct ctl_table tmp = *ctl;
2999 int ret;
3000
3001 tmp.extra1 = &zero;
3002 tmp.extra2 = &int_max;
3003
3004 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
3005 neigh_proc_update(ctl, write);
3006 return ret;
3007}
3008
3009int neigh_proc_dointvec(struct ctl_table *ctl, int write,
3010 void __user *buffer, size_t *lenp, loff_t *ppos)
3011{
3012 int ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
3013
3014 neigh_proc_update(ctl, write);
3015 return ret;
3016}
3017EXPORT_SYMBOL(neigh_proc_dointvec);
3018
3019int neigh_proc_dointvec_jiffies(struct ctl_table *ctl, int write,
3020 void __user *buffer,
3021 size_t *lenp, loff_t *ppos)
3022{
3023 int ret = proc_dointvec_jiffies(ctl, write, buffer, lenp, ppos);
3024
3025 neigh_proc_update(ctl, write);
3026 return ret;
3027}
3028EXPORT_SYMBOL(neigh_proc_dointvec_jiffies);
3029
3030static int neigh_proc_dointvec_userhz_jiffies(struct ctl_table *ctl, int write,
3031 void __user *buffer,
3032 size_t *lenp, loff_t *ppos)
3033{
3034 int ret = proc_dointvec_userhz_jiffies(ctl, write, buffer, lenp, ppos);
3035
3036 neigh_proc_update(ctl, write);
3037 return ret;
3038}
3039
3040int neigh_proc_dointvec_ms_jiffies(struct ctl_table *ctl, int write,
3041 void __user *buffer,
3042 size_t *lenp, loff_t *ppos)
3043{
3044 int ret = proc_dointvec_ms_jiffies(ctl, write, buffer, lenp, ppos);
3045
3046 neigh_proc_update(ctl, write);
3047 return ret;
3048}
3049EXPORT_SYMBOL(neigh_proc_dointvec_ms_jiffies);
3050
3051static int neigh_proc_dointvec_unres_qlen(struct ctl_table *ctl, int write,
3052 void __user *buffer,
3053 size_t *lenp, loff_t *ppos)
3054{
3055 int ret = proc_unres_qlen(ctl, write, buffer, lenp, ppos);
3056
3057 neigh_proc_update(ctl, write);
3058 return ret;
3059}
3060
3061static int neigh_proc_base_reachable_time(struct ctl_table *ctl, int write,
3062 void __user *buffer,
3063 size_t *lenp, loff_t *ppos)
3064{
3065 struct neigh_parms *p = ctl->extra2;
3066 int ret;
3067
3068 if (strcmp(ctl->procname, "base_reachable_time") == 0)
3069 ret = neigh_proc_dointvec_jiffies(ctl, write, buffer, lenp, ppos);
3070 else if (strcmp(ctl->procname, "base_reachable_time_ms") == 0)
3071 ret = neigh_proc_dointvec_ms_jiffies(ctl, write, buffer, lenp, ppos);
3072 else
3073 ret = -1;
3074
3075 if (write && ret == 0) {
3076 /* update reachable_time as well, otherwise, the change will
3077 * only be effective after the next time neigh_periodic_work
3078 * decides to recompute it
3079 */
3080 p->reachable_time =
3081 neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME));
3082 }
3083 return ret;
3084}
3085
3086#define NEIGH_PARMS_DATA_OFFSET(index) \
3087 (&((struct neigh_parms *) 0)->data[index])
3088
3089#define NEIGH_SYSCTL_ENTRY(attr, data_attr, name, mval, proc) \
3090 [NEIGH_VAR_ ## attr] = { \
3091 .procname = name, \
3092 .data = NEIGH_PARMS_DATA_OFFSET(NEIGH_VAR_ ## data_attr), \
3093 .maxlen = sizeof(int), \
3094 .mode = mval, \
3095 .proc_handler = proc, \
3096 }
3097
3098#define NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(attr, name) \
3099 NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_zero_intmax)
3100
3101#define NEIGH_SYSCTL_JIFFIES_ENTRY(attr, name) \
3102 NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_jiffies)
3103
3104#define NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(attr, name) \
3105 NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_userhz_jiffies)
3106
3107#define NEIGH_SYSCTL_MS_JIFFIES_ENTRY(attr, name) \
3108 NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_ms_jiffies)
3109
3110#define NEIGH_SYSCTL_MS_JIFFIES_REUSED_ENTRY(attr, data_attr, name) \
3111 NEIGH_SYSCTL_ENTRY(attr, data_attr, name, 0644, neigh_proc_dointvec_ms_jiffies)
3112
3113#define NEIGH_SYSCTL_UNRES_QLEN_REUSED_ENTRY(attr, data_attr, name) \
3114 NEIGH_SYSCTL_ENTRY(attr, data_attr, name, 0644, neigh_proc_dointvec_unres_qlen)
3115
3116static struct neigh_sysctl_table {
3117 struct ctl_table_header *sysctl_header;
3118 struct ctl_table neigh_vars[NEIGH_VAR_MAX + 1];
3119} neigh_sysctl_template __read_mostly = {
3120 .neigh_vars = {
3121 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(MCAST_PROBES, "mcast_solicit"),
3122 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(UCAST_PROBES, "ucast_solicit"),
3123 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(APP_PROBES, "app_solicit"),
3124 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(MCAST_REPROBES, "mcast_resolicit"),
3125 NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(RETRANS_TIME, "retrans_time"),
3126 NEIGH_SYSCTL_JIFFIES_ENTRY(BASE_REACHABLE_TIME, "base_reachable_time"),
3127 NEIGH_SYSCTL_JIFFIES_ENTRY(DELAY_PROBE_TIME, "delay_first_probe_time"),
3128 NEIGH_SYSCTL_JIFFIES_ENTRY(GC_STALETIME, "gc_stale_time"),
3129 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(QUEUE_LEN_BYTES, "unres_qlen_bytes"),
3130 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(PROXY_QLEN, "proxy_qlen"),
3131 NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(ANYCAST_DELAY, "anycast_delay"),
3132 NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(PROXY_DELAY, "proxy_delay"),
3133 NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(LOCKTIME, "locktime"),
3134 NEIGH_SYSCTL_UNRES_QLEN_REUSED_ENTRY(QUEUE_LEN, QUEUE_LEN_BYTES, "unres_qlen"),
3135 NEIGH_SYSCTL_MS_JIFFIES_REUSED_ENTRY(RETRANS_TIME_MS, RETRANS_TIME, "retrans_time_ms"),
3136 NEIGH_SYSCTL_MS_JIFFIES_REUSED_ENTRY(BASE_REACHABLE_TIME_MS, BASE_REACHABLE_TIME, "base_reachable_time_ms"),
3137 [NEIGH_VAR_GC_INTERVAL] = {
3138 .procname = "gc_interval",
3139 .maxlen = sizeof(int),
3140 .mode = 0644,
3141 .proc_handler = proc_dointvec_jiffies,
3142 },
3143 [NEIGH_VAR_GC_THRESH1] = {
3144 .procname = "gc_thresh1",
3145 .maxlen = sizeof(int),
3146 .mode = 0644,
3147 .extra1 = &zero,
3148 .extra2 = &int_max,
3149 .proc_handler = proc_dointvec_minmax,
3150 },
3151 [NEIGH_VAR_GC_THRESH2] = {
3152 .procname = "gc_thresh2",
3153 .maxlen = sizeof(int),
3154 .mode = 0644,
3155 .extra1 = &zero,
3156 .extra2 = &int_max,
3157 .proc_handler = proc_dointvec_minmax,
3158 },
3159 [NEIGH_VAR_GC_THRESH3] = {
3160 .procname = "gc_thresh3",
3161 .maxlen = sizeof(int),
3162 .mode = 0644,
3163 .extra1 = &zero,
3164 .extra2 = &int_max,
3165 .proc_handler = proc_dointvec_minmax,
3166 },
3167 {},
3168 },
3169};
3170
3171int neigh_sysctl_register(struct net_device *dev, struct neigh_parms *p,
3172 proc_handler *handler)
3173{
3174 int i;
3175 struct neigh_sysctl_table *t;
3176 const char *dev_name_source;
3177 char neigh_path[ sizeof("net//neigh/") + IFNAMSIZ + IFNAMSIZ ];
3178 char *p_name;
3179
3180 t = kmemdup(&neigh_sysctl_template, sizeof(*t), GFP_KERNEL);
3181 if (!t)
3182 goto err;
3183
3184 for (i = 0; i < NEIGH_VAR_GC_INTERVAL; i++) {
3185 t->neigh_vars[i].data += (long) p;
3186 t->neigh_vars[i].extra1 = dev;
3187 t->neigh_vars[i].extra2 = p;
3188 }
3189
3190 if (dev) {
3191 dev_name_source = dev->name;
3192 /* Terminate the table early */
3193 memset(&t->neigh_vars[NEIGH_VAR_GC_INTERVAL], 0,
3194 sizeof(t->neigh_vars[NEIGH_VAR_GC_INTERVAL]));
3195 } else {
3196 struct neigh_table *tbl = p->tbl;
3197 dev_name_source = "default";
3198 t->neigh_vars[NEIGH_VAR_GC_INTERVAL].data = &tbl->gc_interval;
3199 t->neigh_vars[NEIGH_VAR_GC_THRESH1].data = &tbl->gc_thresh1;
3200 t->neigh_vars[NEIGH_VAR_GC_THRESH2].data = &tbl->gc_thresh2;
3201 t->neigh_vars[NEIGH_VAR_GC_THRESH3].data = &tbl->gc_thresh3;
3202 }
3203
3204 if (handler) {
3205 /* RetransTime */
3206 t->neigh_vars[NEIGH_VAR_RETRANS_TIME].proc_handler = handler;
3207 /* ReachableTime */
3208 t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME].proc_handler = handler;
3209 /* RetransTime (in milliseconds)*/
3210 t->neigh_vars[NEIGH_VAR_RETRANS_TIME_MS].proc_handler = handler;
3211 /* ReachableTime (in milliseconds) */
3212 t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME_MS].proc_handler = handler;
3213 } else {
3214 /* Those handlers will update p->reachable_time after
3215 * base_reachable_time(_ms) is set to ensure the new timer starts being
3216 * applied after the next neighbour update instead of waiting for
3217 * neigh_periodic_work to update its value (can be multiple minutes)
3218 * So any handler that replaces them should do this as well
3219 */
3220 /* ReachableTime */
3221 t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME].proc_handler =
3222 neigh_proc_base_reachable_time;
3223 /* ReachableTime (in milliseconds) */
3224 t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME_MS].proc_handler =
3225 neigh_proc_base_reachable_time;
3226 }
3227
3228 /* Don't export sysctls to unprivileged users */
3229 if (neigh_parms_net(p)->user_ns != &init_user_ns)
3230 t->neigh_vars[0].procname = NULL;
3231
3232 switch (neigh_parms_family(p)) {
3233 case AF_INET:
3234 p_name = "ipv4";
3235 break;
3236 case AF_INET6:
3237 p_name = "ipv6";
3238 break;
3239 default:
3240 BUG();
3241 }
3242
3243 snprintf(neigh_path, sizeof(neigh_path), "net/%s/neigh/%s",
3244 p_name, dev_name_source);
3245 t->sysctl_header =
3246 register_net_sysctl(neigh_parms_net(p), neigh_path, t->neigh_vars);
3247 if (!t->sysctl_header)
3248 goto free;
3249
3250 p->sysctl_table = t;
3251 return 0;
3252
3253free:
3254 kfree(t);
3255err:
3256 return -ENOBUFS;
3257}
3258EXPORT_SYMBOL(neigh_sysctl_register);
3259
3260void neigh_sysctl_unregister(struct neigh_parms *p)
3261{
3262 if (p->sysctl_table) {
3263 struct neigh_sysctl_table *t = p->sysctl_table;
3264 p->sysctl_table = NULL;
3265 unregister_net_sysctl_table(t->sysctl_header);
3266 kfree(t);
3267 }
3268}
3269EXPORT_SYMBOL(neigh_sysctl_unregister);
3270
3271#endif /* CONFIG_SYSCTL */
3272
3273static int __init neigh_init(void)
3274{
3275 rtnl_register(PF_UNSPEC, RTM_NEWNEIGH, neigh_add, NULL, 0);
3276 rtnl_register(PF_UNSPEC, RTM_DELNEIGH, neigh_delete, NULL, 0);
3277 rtnl_register(PF_UNSPEC, RTM_GETNEIGH, NULL, neigh_dump_info, 0);
3278
3279 rtnl_register(PF_UNSPEC, RTM_GETNEIGHTBL, NULL, neightbl_dump_info,
3280 0);
3281 rtnl_register(PF_UNSPEC, RTM_SETNEIGHTBL, neightbl_set, NULL, 0);
3282
3283 return 0;
3284}
3285
3286subsys_initcall(neigh_init);
3287