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1/*
2 * Generic address resolution entity
3 *
4 * Authors:
5 * Pedro Roque <roque@di.fc.ul.pt>
6 * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License
10 * as published by the Free Software Foundation; either version
11 * 2 of the License, or (at your option) any later version.
12 *
13 * Fixes:
14 * Vitaly E. Lavrov releasing NULL neighbor in neigh_add.
15 * Harald Welte Add neighbour cache statistics like rtstat
16 */
17
18#include <linux/slab.h>
19#include <linux/types.h>
20#include <linux/kernel.h>
21#include <linux/module.h>
22#include <linux/socket.h>
23#include <linux/netdevice.h>
24#include <linux/proc_fs.h>
25#ifdef CONFIG_SYSCTL
26#include <linux/sysctl.h>
27#endif
28#include <linux/times.h>
29#include <net/net_namespace.h>
30#include <net/neighbour.h>
31#include <net/dst.h>
32#include <net/sock.h>
33#include <net/netevent.h>
34#include <net/netlink.h>
35#include <linux/rtnetlink.h>
36#include <linux/random.h>
37#include <linux/string.h>
38#include <linux/log2.h>
39
40#define NEIGH_DEBUG 1
41
42#define NEIGH_PRINTK(x...) printk(x)
43#define NEIGH_NOPRINTK(x...) do { ; } while(0)
44#define NEIGH_PRINTK1 NEIGH_NOPRINTK
45#define NEIGH_PRINTK2 NEIGH_NOPRINTK
46
47#if NEIGH_DEBUG >= 1
48#undef NEIGH_PRINTK1
49#define NEIGH_PRINTK1 NEIGH_PRINTK
50#endif
51#if NEIGH_DEBUG >= 2
52#undef NEIGH_PRINTK2
53#define NEIGH_PRINTK2 NEIGH_PRINTK
54#endif
55
56#define PNEIGH_HASHMASK 0xF
57
58static void neigh_timer_handler(unsigned long arg);
59static void __neigh_notify(struct neighbour *n, int type, int flags);
60static void neigh_update_notify(struct neighbour *neigh);
61static int pneigh_ifdown(struct neigh_table *tbl, struct net_device *dev);
62
63static struct neigh_table *neigh_tables;
64#ifdef CONFIG_PROC_FS
65static const struct file_operations neigh_stat_seq_fops;
66#endif
67
68/*
69 Neighbour hash table buckets are protected with rwlock tbl->lock.
70
71 - All the scans/updates to hash buckets MUST be made under this lock.
72 - NOTHING clever should be made under this lock: no callbacks
73 to protocol backends, no attempts to send something to network.
74 It will result in deadlocks, if backend/driver wants to use neighbour
75 cache.
76 - If the entry requires some non-trivial actions, increase
77 its reference count and release table lock.
78
79 Neighbour entries are protected:
80 - with reference count.
81 - with rwlock neigh->lock
82
83 Reference count prevents destruction.
84
85 neigh->lock mainly serializes ll address data and its validity state.
86 However, the same lock is used to protect another entry fields:
87 - timer
88 - resolution queue
89
90 Again, nothing clever shall be made under neigh->lock,
91 the most complicated procedure, which we allow is dev->hard_header.
92 It is supposed, that dev->hard_header is simplistic and does
93 not make callbacks to neighbour tables.
94
95 The last lock is neigh_tbl_lock. It is pure SMP lock, protecting
96 list of neighbour tables. This list is used only in process context,
97 */
98
99static DEFINE_RWLOCK(neigh_tbl_lock);
100
101static int neigh_blackhole(struct neighbour *neigh, struct sk_buff *skb)
102{
103 kfree_skb(skb);
104 return -ENETDOWN;
105}
106
107static void neigh_cleanup_and_release(struct neighbour *neigh)
108{
109 if (neigh->parms->neigh_cleanup)
110 neigh->parms->neigh_cleanup(neigh);
111
112 __neigh_notify(neigh, RTM_DELNEIGH, 0);
113 neigh_release(neigh);
114}
115
116/*
117 * It is random distribution in the interval (1/2)*base...(3/2)*base.
118 * It corresponds to default IPv6 settings and is not overridable,
119 * because it is really reasonable choice.
120 */
121
122unsigned long neigh_rand_reach_time(unsigned long base)
123{
124 return base ? (net_random() % base) + (base >> 1) : 0;
125}
126EXPORT_SYMBOL(neigh_rand_reach_time);
127
128
129static int neigh_forced_gc(struct neigh_table *tbl)
130{
131 int shrunk = 0;
132 int i;
133 struct neigh_hash_table *nht;
134
135 NEIGH_CACHE_STAT_INC(tbl, forced_gc_runs);
136
137 write_lock_bh(&tbl->lock);
138 nht = rcu_dereference_protected(tbl->nht,
139 lockdep_is_held(&tbl->lock));
140 for (i = 0; i < (1 << nht->hash_shift); i++) {
141 struct neighbour *n;
142 struct neighbour __rcu **np;
143
144 np = &nht->hash_buckets[i];
145 while ((n = rcu_dereference_protected(*np,
146 lockdep_is_held(&tbl->lock))) != NULL) {
147 /* Neighbour record may be discarded if:
148 * - nobody refers to it.
149 * - it is not permanent
150 */
151 write_lock(&n->lock);
152 if (atomic_read(&n->refcnt) == 1 &&
153 !(n->nud_state & NUD_PERMANENT)) {
154 rcu_assign_pointer(*np,
155 rcu_dereference_protected(n->next,
156 lockdep_is_held(&tbl->lock)));
157 n->dead = 1;
158 shrunk = 1;
159 write_unlock(&n->lock);
160 neigh_cleanup_and_release(n);
161 continue;
162 }
163 write_unlock(&n->lock);
164 np = &n->next;
165 }
166 }
167
168 tbl->last_flush = jiffies;
169
170 write_unlock_bh(&tbl->lock);
171
172 return shrunk;
173}
174
175static void neigh_add_timer(struct neighbour *n, unsigned long when)
176{
177 neigh_hold(n);
178 if (unlikely(mod_timer(&n->timer, when))) {
179 printk("NEIGH: BUG, double timer add, state is %x\n",
180 n->nud_state);
181 dump_stack();
182 }
183}
184
185static int neigh_del_timer(struct neighbour *n)
186{
187 if ((n->nud_state & NUD_IN_TIMER) &&
188 del_timer(&n->timer)) {
189 neigh_release(n);
190 return 1;
191 }
192 return 0;
193}
194
195static void pneigh_queue_purge(struct sk_buff_head *list)
196{
197 struct sk_buff *skb;
198
199 while ((skb = skb_dequeue(list)) != NULL) {
200 dev_put(skb->dev);
201 kfree_skb(skb);
202 }
203}
204
205static void neigh_flush_dev(struct neigh_table *tbl, struct net_device *dev)
206{
207 int i;
208 struct neigh_hash_table *nht;
209
210 nht = rcu_dereference_protected(tbl->nht,
211 lockdep_is_held(&tbl->lock));
212
213 for (i = 0; i < (1 << nht->hash_shift); i++) {
214 struct neighbour *n;
215 struct neighbour __rcu **np = &nht->hash_buckets[i];
216
217 while ((n = rcu_dereference_protected(*np,
218 lockdep_is_held(&tbl->lock))) != NULL) {
219 if (dev && n->dev != dev) {
220 np = &n->next;
221 continue;
222 }
223 rcu_assign_pointer(*np,
224 rcu_dereference_protected(n->next,
225 lockdep_is_held(&tbl->lock)));
226 write_lock(&n->lock);
227 neigh_del_timer(n);
228 n->dead = 1;
229
230 if (atomic_read(&n->refcnt) != 1) {
231 /* The most unpleasant situation.
232 We must destroy neighbour entry,
233 but someone still uses it.
234
235 The destroy will be delayed until
236 the last user releases us, but
237 we must kill timers etc. and move
238 it to safe state.
239 */
240 skb_queue_purge(&n->arp_queue);
241 n->output = neigh_blackhole;
242 if (n->nud_state & NUD_VALID)
243 n->nud_state = NUD_NOARP;
244 else
245 n->nud_state = NUD_NONE;
246 NEIGH_PRINTK2("neigh %p is stray.\n", n);
247 }
248 write_unlock(&n->lock);
249 neigh_cleanup_and_release(n);
250 }
251 }
252}
253
254void neigh_changeaddr(struct neigh_table *tbl, struct net_device *dev)
255{
256 write_lock_bh(&tbl->lock);
257 neigh_flush_dev(tbl, dev);
258 write_unlock_bh(&tbl->lock);
259}
260EXPORT_SYMBOL(neigh_changeaddr);
261
262int neigh_ifdown(struct neigh_table *tbl, struct net_device *dev)
263{
264 write_lock_bh(&tbl->lock);
265 neigh_flush_dev(tbl, dev);
266 pneigh_ifdown(tbl, dev);
267 write_unlock_bh(&tbl->lock);
268
269 del_timer_sync(&tbl->proxy_timer);
270 pneigh_queue_purge(&tbl->proxy_queue);
271 return 0;
272}
273EXPORT_SYMBOL(neigh_ifdown);
274
275static struct neighbour *neigh_alloc(struct neigh_table *tbl)
276{
277 struct neighbour *n = NULL;
278 unsigned long now = jiffies;
279 int entries;
280
281 entries = atomic_inc_return(&tbl->entries) - 1;
282 if (entries >= tbl->gc_thresh3 ||
283 (entries >= tbl->gc_thresh2 &&
284 time_after(now, tbl->last_flush + 5 * HZ))) {
285 if (!neigh_forced_gc(tbl) &&
286 entries >= tbl->gc_thresh3)
287 goto out_entries;
288 }
289
290 n = kmem_cache_zalloc(tbl->kmem_cachep, GFP_ATOMIC);
291 if (!n)
292 goto out_entries;
293
294 skb_queue_head_init(&n->arp_queue);
295 rwlock_init(&n->lock);
296 seqlock_init(&n->ha_lock);
297 n->updated = n->used = now;
298 n->nud_state = NUD_NONE;
299 n->output = neigh_blackhole;
300 seqlock_init(&n->hh.hh_lock);
301 n->parms = neigh_parms_clone(&tbl->parms);
302 setup_timer(&n->timer, neigh_timer_handler, (unsigned long)n);
303
304 NEIGH_CACHE_STAT_INC(tbl, allocs);
305 n->tbl = tbl;
306 atomic_set(&n->refcnt, 1);
307 n->dead = 1;
308out:
309 return n;
310
311out_entries:
312 atomic_dec(&tbl->entries);
313 goto out;
314}
315
316static struct neigh_hash_table *neigh_hash_alloc(unsigned int shift)
317{
318 size_t size = (1 << shift) * sizeof(struct neighbour *);
319 struct neigh_hash_table *ret;
320 struct neighbour __rcu **buckets;
321
322 ret = kmalloc(sizeof(*ret), GFP_ATOMIC);
323 if (!ret)
324 return NULL;
325 if (size <= PAGE_SIZE)
326 buckets = kzalloc(size, GFP_ATOMIC);
327 else
328 buckets = (struct neighbour __rcu **)
329 __get_free_pages(GFP_ATOMIC | __GFP_ZERO,
330 get_order(size));
331 if (!buckets) {
332 kfree(ret);
333 return NULL;
334 }
335 ret->hash_buckets = buckets;
336 ret->hash_shift = shift;
337 get_random_bytes(&ret->hash_rnd, sizeof(ret->hash_rnd));
338 ret->hash_rnd |= 1;
339 return ret;
340}
341
342static void neigh_hash_free_rcu(struct rcu_head *head)
343{
344 struct neigh_hash_table *nht = container_of(head,
345 struct neigh_hash_table,
346 rcu);
347 size_t size = (1 << nht->hash_shift) * sizeof(struct neighbour *);
348 struct neighbour __rcu **buckets = nht->hash_buckets;
349
350 if (size <= PAGE_SIZE)
351 kfree(buckets);
352 else
353 free_pages((unsigned long)buckets, get_order(size));
354 kfree(nht);
355}
356
357static struct neigh_hash_table *neigh_hash_grow(struct neigh_table *tbl,
358 unsigned long new_shift)
359{
360 unsigned int i, hash;
361 struct neigh_hash_table *new_nht, *old_nht;
362
363 NEIGH_CACHE_STAT_INC(tbl, hash_grows);
364
365 old_nht = rcu_dereference_protected(tbl->nht,
366 lockdep_is_held(&tbl->lock));
367 new_nht = neigh_hash_alloc(new_shift);
368 if (!new_nht)
369 return old_nht;
370
371 for (i = 0; i < (1 << old_nht->hash_shift); i++) {
372 struct neighbour *n, *next;
373
374 for (n = rcu_dereference_protected(old_nht->hash_buckets[i],
375 lockdep_is_held(&tbl->lock));
376 n != NULL;
377 n = next) {
378 hash = tbl->hash(n->primary_key, n->dev,
379 new_nht->hash_rnd);
380
381 hash >>= (32 - new_nht->hash_shift);
382 next = rcu_dereference_protected(n->next,
383 lockdep_is_held(&tbl->lock));
384
385 rcu_assign_pointer(n->next,
386 rcu_dereference_protected(
387 new_nht->hash_buckets[hash],
388 lockdep_is_held(&tbl->lock)));
389 rcu_assign_pointer(new_nht->hash_buckets[hash], n);
390 }
391 }
392
393 rcu_assign_pointer(tbl->nht, new_nht);
394 call_rcu(&old_nht->rcu, neigh_hash_free_rcu);
395 return new_nht;
396}
397
398struct neighbour *neigh_lookup(struct neigh_table *tbl, const void *pkey,
399 struct net_device *dev)
400{
401 struct neighbour *n;
402 int key_len = tbl->key_len;
403 u32 hash_val;
404 struct neigh_hash_table *nht;
405
406 NEIGH_CACHE_STAT_INC(tbl, lookups);
407
408 rcu_read_lock_bh();
409 nht = rcu_dereference_bh(tbl->nht);
410 hash_val = tbl->hash(pkey, dev, nht->hash_rnd) >> (32 - nht->hash_shift);
411
412 for (n = rcu_dereference_bh(nht->hash_buckets[hash_val]);
413 n != NULL;
414 n = rcu_dereference_bh(n->next)) {
415 if (dev == n->dev && !memcmp(n->primary_key, pkey, key_len)) {
416 if (!atomic_inc_not_zero(&n->refcnt))
417 n = NULL;
418 NEIGH_CACHE_STAT_INC(tbl, hits);
419 break;
420 }
421 }
422
423 rcu_read_unlock_bh();
424 return n;
425}
426EXPORT_SYMBOL(neigh_lookup);
427
428struct neighbour *neigh_lookup_nodev(struct neigh_table *tbl, struct net *net,
429 const void *pkey)
430{
431 struct neighbour *n;
432 int key_len = tbl->key_len;
433 u32 hash_val;
434 struct neigh_hash_table *nht;
435
436 NEIGH_CACHE_STAT_INC(tbl, lookups);
437
438 rcu_read_lock_bh();
439 nht = rcu_dereference_bh(tbl->nht);
440 hash_val = tbl->hash(pkey, NULL, nht->hash_rnd) >> (32 - nht->hash_shift);
441
442 for (n = rcu_dereference_bh(nht->hash_buckets[hash_val]);
443 n != NULL;
444 n = rcu_dereference_bh(n->next)) {
445 if (!memcmp(n->primary_key, pkey, key_len) &&
446 net_eq(dev_net(n->dev), net)) {
447 if (!atomic_inc_not_zero(&n->refcnt))
448 n = NULL;
449 NEIGH_CACHE_STAT_INC(tbl, hits);
450 break;
451 }
452 }
453
454 rcu_read_unlock_bh();
455 return n;
456}
457EXPORT_SYMBOL(neigh_lookup_nodev);
458
459struct neighbour *neigh_create(struct neigh_table *tbl, const void *pkey,
460 struct net_device *dev)
461{
462 u32 hash_val;
463 int key_len = tbl->key_len;
464 int error;
465 struct neighbour *n1, *rc, *n = neigh_alloc(tbl);
466 struct neigh_hash_table *nht;
467
468 if (!n) {
469 rc = ERR_PTR(-ENOBUFS);
470 goto out;
471 }
472
473 memcpy(n->primary_key, pkey, key_len);
474 n->dev = dev;
475 dev_hold(dev);
476
477 /* Protocol specific setup. */
478 if (tbl->constructor && (error = tbl->constructor(n)) < 0) {
479 rc = ERR_PTR(error);
480 goto out_neigh_release;
481 }
482
483 /* Device specific setup. */
484 if (n->parms->neigh_setup &&
485 (error = n->parms->neigh_setup(n)) < 0) {
486 rc = ERR_PTR(error);
487 goto out_neigh_release;
488 }
489
490 n->confirmed = jiffies - (n->parms->base_reachable_time << 1);
491
492 write_lock_bh(&tbl->lock);
493 nht = rcu_dereference_protected(tbl->nht,
494 lockdep_is_held(&tbl->lock));
495
496 if (atomic_read(&tbl->entries) > (1 << nht->hash_shift))
497 nht = neigh_hash_grow(tbl, nht->hash_shift + 1);
498
499 hash_val = tbl->hash(pkey, dev, nht->hash_rnd) >> (32 - nht->hash_shift);
500
501 if (n->parms->dead) {
502 rc = ERR_PTR(-EINVAL);
503 goto out_tbl_unlock;
504 }
505
506 for (n1 = rcu_dereference_protected(nht->hash_buckets[hash_val],
507 lockdep_is_held(&tbl->lock));
508 n1 != NULL;
509 n1 = rcu_dereference_protected(n1->next,
510 lockdep_is_held(&tbl->lock))) {
511 if (dev == n1->dev && !memcmp(n1->primary_key, pkey, key_len)) {
512 neigh_hold(n1);
513 rc = n1;
514 goto out_tbl_unlock;
515 }
516 }
517
518 n->dead = 0;
519 neigh_hold(n);
520 rcu_assign_pointer(n->next,
521 rcu_dereference_protected(nht->hash_buckets[hash_val],
522 lockdep_is_held(&tbl->lock)));
523 rcu_assign_pointer(nht->hash_buckets[hash_val], n);
524 write_unlock_bh(&tbl->lock);
525 NEIGH_PRINTK2("neigh %p is created.\n", n);
526 rc = n;
527out:
528 return rc;
529out_tbl_unlock:
530 write_unlock_bh(&tbl->lock);
531out_neigh_release:
532 neigh_release(n);
533 goto out;
534}
535EXPORT_SYMBOL(neigh_create);
536
537static u32 pneigh_hash(const void *pkey, int key_len)
538{
539 u32 hash_val = *(u32 *)(pkey + key_len - 4);
540 hash_val ^= (hash_val >> 16);
541 hash_val ^= hash_val >> 8;
542 hash_val ^= hash_val >> 4;
543 hash_val &= PNEIGH_HASHMASK;
544 return hash_val;
545}
546
547static struct pneigh_entry *__pneigh_lookup_1(struct pneigh_entry *n,
548 struct net *net,
549 const void *pkey,
550 int key_len,
551 struct net_device *dev)
552{
553 while (n) {
554 if (!memcmp(n->key, pkey, key_len) &&
555 net_eq(pneigh_net(n), net) &&
556 (n->dev == dev || !n->dev))
557 return n;
558 n = n->next;
559 }
560 return NULL;
561}
562
563struct pneigh_entry *__pneigh_lookup(struct neigh_table *tbl,
564 struct net *net, const void *pkey, struct net_device *dev)
565{
566 int key_len = tbl->key_len;
567 u32 hash_val = pneigh_hash(pkey, key_len);
568
569 return __pneigh_lookup_1(tbl->phash_buckets[hash_val],
570 net, pkey, key_len, dev);
571}
572EXPORT_SYMBOL_GPL(__pneigh_lookup);
573
574struct pneigh_entry * pneigh_lookup(struct neigh_table *tbl,
575 struct net *net, const void *pkey,
576 struct net_device *dev, int creat)
577{
578 struct pneigh_entry *n;
579 int key_len = tbl->key_len;
580 u32 hash_val = pneigh_hash(pkey, key_len);
581
582 read_lock_bh(&tbl->lock);
583 n = __pneigh_lookup_1(tbl->phash_buckets[hash_val],
584 net, pkey, key_len, dev);
585 read_unlock_bh(&tbl->lock);
586
587 if (n || !creat)
588 goto out;
589
590 ASSERT_RTNL();
591
592 n = kmalloc(sizeof(*n) + key_len, GFP_KERNEL);
593 if (!n)
594 goto out;
595
596 write_pnet(&n->net, hold_net(net));
597 memcpy(n->key, pkey, key_len);
598 n->dev = dev;
599 if (dev)
600 dev_hold(dev);
601
602 if (tbl->pconstructor && tbl->pconstructor(n)) {
603 if (dev)
604 dev_put(dev);
605 release_net(net);
606 kfree(n);
607 n = NULL;
608 goto out;
609 }
610
611 write_lock_bh(&tbl->lock);
612 n->next = tbl->phash_buckets[hash_val];
613 tbl->phash_buckets[hash_val] = n;
614 write_unlock_bh(&tbl->lock);
615out:
616 return n;
617}
618EXPORT_SYMBOL(pneigh_lookup);
619
620
621int pneigh_delete(struct neigh_table *tbl, struct net *net, const void *pkey,
622 struct net_device *dev)
623{
624 struct pneigh_entry *n, **np;
625 int key_len = tbl->key_len;
626 u32 hash_val = pneigh_hash(pkey, key_len);
627
628 write_lock_bh(&tbl->lock);
629 for (np = &tbl->phash_buckets[hash_val]; (n = *np) != NULL;
630 np = &n->next) {
631 if (!memcmp(n->key, pkey, key_len) && n->dev == dev &&
632 net_eq(pneigh_net(n), net)) {
633 *np = n->next;
634 write_unlock_bh(&tbl->lock);
635 if (tbl->pdestructor)
636 tbl->pdestructor(n);
637 if (n->dev)
638 dev_put(n->dev);
639 release_net(pneigh_net(n));
640 kfree(n);
641 return 0;
642 }
643 }
644 write_unlock_bh(&tbl->lock);
645 return -ENOENT;
646}
647
648static int pneigh_ifdown(struct neigh_table *tbl, struct net_device *dev)
649{
650 struct pneigh_entry *n, **np;
651 u32 h;
652
653 for (h = 0; h <= PNEIGH_HASHMASK; h++) {
654 np = &tbl->phash_buckets[h];
655 while ((n = *np) != NULL) {
656 if (!dev || n->dev == dev) {
657 *np = n->next;
658 if (tbl->pdestructor)
659 tbl->pdestructor(n);
660 if (n->dev)
661 dev_put(n->dev);
662 release_net(pneigh_net(n));
663 kfree(n);
664 continue;
665 }
666 np = &n->next;
667 }
668 }
669 return -ENOENT;
670}
671
672static void neigh_parms_destroy(struct neigh_parms *parms);
673
674static inline void neigh_parms_put(struct neigh_parms *parms)
675{
676 if (atomic_dec_and_test(&parms->refcnt))
677 neigh_parms_destroy(parms);
678}
679
680static void neigh_destroy_rcu(struct rcu_head *head)
681{
682 struct neighbour *neigh = container_of(head, struct neighbour, rcu);
683
684 kmem_cache_free(neigh->tbl->kmem_cachep, neigh);
685}
686/*
687 * neighbour must already be out of the table;
688 *
689 */
690void neigh_destroy(struct neighbour *neigh)
691{
692 NEIGH_CACHE_STAT_INC(neigh->tbl, destroys);
693
694 if (!neigh->dead) {
695 printk(KERN_WARNING
696 "Destroying alive neighbour %p\n", neigh);
697 dump_stack();
698 return;
699 }
700
701 if (neigh_del_timer(neigh))
702 printk(KERN_WARNING "Impossible event.\n");
703
704 skb_queue_purge(&neigh->arp_queue);
705
706 dev_put(neigh->dev);
707 neigh_parms_put(neigh->parms);
708
709 NEIGH_PRINTK2("neigh %p is destroyed.\n", neigh);
710
711 atomic_dec(&neigh->tbl->entries);
712 call_rcu(&neigh->rcu, neigh_destroy_rcu);
713}
714EXPORT_SYMBOL(neigh_destroy);
715
716/* Neighbour state is suspicious;
717 disable fast path.
718
719 Called with write_locked neigh.
720 */
721static void neigh_suspect(struct neighbour *neigh)
722{
723 NEIGH_PRINTK2("neigh %p is suspected.\n", neigh);
724
725 neigh->output = neigh->ops->output;
726}
727
728/* Neighbour state is OK;
729 enable fast path.
730
731 Called with write_locked neigh.
732 */
733static void neigh_connect(struct neighbour *neigh)
734{
735 NEIGH_PRINTK2("neigh %p is connected.\n", neigh);
736
737 neigh->output = neigh->ops->connected_output;
738}
739
740static void neigh_periodic_work(struct work_struct *work)
741{
742 struct neigh_table *tbl = container_of(work, struct neigh_table, gc_work.work);
743 struct neighbour *n;
744 struct neighbour __rcu **np;
745 unsigned int i;
746 struct neigh_hash_table *nht;
747
748 NEIGH_CACHE_STAT_INC(tbl, periodic_gc_runs);
749
750 write_lock_bh(&tbl->lock);
751 nht = rcu_dereference_protected(tbl->nht,
752 lockdep_is_held(&tbl->lock));
753
754 /*
755 * periodically recompute ReachableTime from random function
756 */
757
758 if (time_after(jiffies, tbl->last_rand + 300 * HZ)) {
759 struct neigh_parms *p;
760 tbl->last_rand = jiffies;
761 for (p = &tbl->parms; p; p = p->next)
762 p->reachable_time =
763 neigh_rand_reach_time(p->base_reachable_time);
764 }
765
766 for (i = 0 ; i < (1 << nht->hash_shift); i++) {
767 np = &nht->hash_buckets[i];
768
769 while ((n = rcu_dereference_protected(*np,
770 lockdep_is_held(&tbl->lock))) != NULL) {
771 unsigned int state;
772
773 write_lock(&n->lock);
774
775 state = n->nud_state;
776 if (state & (NUD_PERMANENT | NUD_IN_TIMER)) {
777 write_unlock(&n->lock);
778 goto next_elt;
779 }
780
781 if (time_before(n->used, n->confirmed))
782 n->used = n->confirmed;
783
784 if (atomic_read(&n->refcnt) == 1 &&
785 (state == NUD_FAILED ||
786 time_after(jiffies, n->used + n->parms->gc_staletime))) {
787 *np = n->next;
788 n->dead = 1;
789 write_unlock(&n->lock);
790 neigh_cleanup_and_release(n);
791 continue;
792 }
793 write_unlock(&n->lock);
794
795next_elt:
796 np = &n->next;
797 }
798 /*
799 * It's fine to release lock here, even if hash table
800 * grows while we are preempted.
801 */
802 write_unlock_bh(&tbl->lock);
803 cond_resched();
804 write_lock_bh(&tbl->lock);
805 }
806 /* Cycle through all hash buckets every base_reachable_time/2 ticks.
807 * ARP entry timeouts range from 1/2 base_reachable_time to 3/2
808 * base_reachable_time.
809 */
810 schedule_delayed_work(&tbl->gc_work,
811 tbl->parms.base_reachable_time >> 1);
812 write_unlock_bh(&tbl->lock);
813}
814
815static __inline__ int neigh_max_probes(struct neighbour *n)
816{
817 struct neigh_parms *p = n->parms;
818 return (n->nud_state & NUD_PROBE) ?
819 p->ucast_probes :
820 p->ucast_probes + p->app_probes + p->mcast_probes;
821}
822
823static void neigh_invalidate(struct neighbour *neigh)
824 __releases(neigh->lock)
825 __acquires(neigh->lock)
826{
827 struct sk_buff *skb;
828
829 NEIGH_CACHE_STAT_INC(neigh->tbl, res_failed);
830 NEIGH_PRINTK2("neigh %p is failed.\n", neigh);
831 neigh->updated = jiffies;
832
833 /* It is very thin place. report_unreachable is very complicated
834 routine. Particularly, it can hit the same neighbour entry!
835
836 So that, we try to be accurate and avoid dead loop. --ANK
837 */
838 while (neigh->nud_state == NUD_FAILED &&
839 (skb = __skb_dequeue(&neigh->arp_queue)) != NULL) {
840 write_unlock(&neigh->lock);
841 neigh->ops->error_report(neigh, skb);
842 write_lock(&neigh->lock);
843 }
844 skb_queue_purge(&neigh->arp_queue);
845}
846
847/* Called when a timer expires for a neighbour entry. */
848
849static void neigh_timer_handler(unsigned long arg)
850{
851 unsigned long now, next;
852 struct neighbour *neigh = (struct neighbour *)arg;
853 unsigned state;
854 int notify = 0;
855
856 write_lock(&neigh->lock);
857
858 state = neigh->nud_state;
859 now = jiffies;
860 next = now + HZ;
861
862 if (!(state & NUD_IN_TIMER)) {
863#ifndef CONFIG_SMP
864 printk(KERN_WARNING "neigh: timer & !nud_in_timer\n");
865#endif
866 goto out;
867 }
868
869 if (state & NUD_REACHABLE) {
870 if (time_before_eq(now,
871 neigh->confirmed + neigh->parms->reachable_time)) {
872 NEIGH_PRINTK2("neigh %p is still alive.\n", neigh);
873 next = neigh->confirmed + neigh->parms->reachable_time;
874 } else if (time_before_eq(now,
875 neigh->used + neigh->parms->delay_probe_time)) {
876 NEIGH_PRINTK2("neigh %p is delayed.\n", neigh);
877 neigh->nud_state = NUD_DELAY;
878 neigh->updated = jiffies;
879 neigh_suspect(neigh);
880 next = now + neigh->parms->delay_probe_time;
881 } else {
882 NEIGH_PRINTK2("neigh %p is suspected.\n", neigh);
883 neigh->nud_state = NUD_STALE;
884 neigh->updated = jiffies;
885 neigh_suspect(neigh);
886 notify = 1;
887 }
888 } else if (state & NUD_DELAY) {
889 if (time_before_eq(now,
890 neigh->confirmed + neigh->parms->delay_probe_time)) {
891 NEIGH_PRINTK2("neigh %p is now reachable.\n", neigh);
892 neigh->nud_state = NUD_REACHABLE;
893 neigh->updated = jiffies;
894 neigh_connect(neigh);
895 notify = 1;
896 next = neigh->confirmed + neigh->parms->reachable_time;
897 } else {
898 NEIGH_PRINTK2("neigh %p is probed.\n", neigh);
899 neigh->nud_state = NUD_PROBE;
900 neigh->updated = jiffies;
901 atomic_set(&neigh->probes, 0);
902 next = now + neigh->parms->retrans_time;
903 }
904 } else {
905 /* NUD_PROBE|NUD_INCOMPLETE */
906 next = now + neigh->parms->retrans_time;
907 }
908
909 if ((neigh->nud_state & (NUD_INCOMPLETE | NUD_PROBE)) &&
910 atomic_read(&neigh->probes) >= neigh_max_probes(neigh)) {
911 neigh->nud_state = NUD_FAILED;
912 notify = 1;
913 neigh_invalidate(neigh);
914 }
915
916 if (neigh->nud_state & NUD_IN_TIMER) {
917 if (time_before(next, jiffies + HZ/2))
918 next = jiffies + HZ/2;
919 if (!mod_timer(&neigh->timer, next))
920 neigh_hold(neigh);
921 }
922 if (neigh->nud_state & (NUD_INCOMPLETE | NUD_PROBE)) {
923 struct sk_buff *skb = skb_peek(&neigh->arp_queue);
924 /* keep skb alive even if arp_queue overflows */
925 if (skb)
926 skb = skb_copy(skb, GFP_ATOMIC);
927 write_unlock(&neigh->lock);
928 neigh->ops->solicit(neigh, skb);
929 atomic_inc(&neigh->probes);
930 kfree_skb(skb);
931 } else {
932out:
933 write_unlock(&neigh->lock);
934 }
935
936 if (notify)
937 neigh_update_notify(neigh);
938
939 neigh_release(neigh);
940}
941
942int __neigh_event_send(struct neighbour *neigh, struct sk_buff *skb)
943{
944 int rc;
945 unsigned long now;
946
947 write_lock_bh(&neigh->lock);
948
949 rc = 0;
950 if (neigh->nud_state & (NUD_CONNECTED | NUD_DELAY | NUD_PROBE))
951 goto out_unlock_bh;
952
953 now = jiffies;
954
955 if (!(neigh->nud_state & (NUD_STALE | NUD_INCOMPLETE))) {
956 if (neigh->parms->mcast_probes + neigh->parms->app_probes) {
957 atomic_set(&neigh->probes, neigh->parms->ucast_probes);
958 neigh->nud_state = NUD_INCOMPLETE;
959 neigh->updated = jiffies;
960 neigh_add_timer(neigh, now + 1);
961 } else {
962 neigh->nud_state = NUD_FAILED;
963 neigh->updated = jiffies;
964 write_unlock_bh(&neigh->lock);
965
966 kfree_skb(skb);
967 return 1;
968 }
969 } else if (neigh->nud_state & NUD_STALE) {
970 NEIGH_PRINTK2("neigh %p is delayed.\n", neigh);
971 neigh->nud_state = NUD_DELAY;
972 neigh->updated = jiffies;
973 neigh_add_timer(neigh,
974 jiffies + neigh->parms->delay_probe_time);
975 }
976
977 if (neigh->nud_state == NUD_INCOMPLETE) {
978 if (skb) {
979 if (skb_queue_len(&neigh->arp_queue) >=
980 neigh->parms->queue_len) {
981 struct sk_buff *buff;
982 buff = __skb_dequeue(&neigh->arp_queue);
983 kfree_skb(buff);
984 NEIGH_CACHE_STAT_INC(neigh->tbl, unres_discards);
985 }
986 skb_dst_force(skb);
987 __skb_queue_tail(&neigh->arp_queue, skb);
988 }
989 rc = 1;
990 }
991out_unlock_bh:
992 write_unlock_bh(&neigh->lock);
993 return rc;
994}
995EXPORT_SYMBOL(__neigh_event_send);
996
997static void neigh_update_hhs(struct neighbour *neigh)
998{
999 struct hh_cache *hh;
1000 void (*update)(struct hh_cache*, const struct net_device*, const unsigned char *)
1001 = NULL;
1002
1003 if (neigh->dev->header_ops)
1004 update = neigh->dev->header_ops->cache_update;
1005
1006 if (update) {
1007 hh = &neigh->hh;
1008 if (hh->hh_len) {
1009 write_seqlock_bh(&hh->hh_lock);
1010 update(hh, neigh->dev, neigh->ha);
1011 write_sequnlock_bh(&hh->hh_lock);
1012 }
1013 }
1014}
1015
1016
1017
1018/* Generic update routine.
1019 -- lladdr is new lladdr or NULL, if it is not supplied.
1020 -- new is new state.
1021 -- flags
1022 NEIGH_UPDATE_F_OVERRIDE allows to override existing lladdr,
1023 if it is different.
1024 NEIGH_UPDATE_F_WEAK_OVERRIDE will suspect existing "connected"
1025 lladdr instead of overriding it
1026 if it is different.
1027 It also allows to retain current state
1028 if lladdr is unchanged.
1029 NEIGH_UPDATE_F_ADMIN means that the change is administrative.
1030
1031 NEIGH_UPDATE_F_OVERRIDE_ISROUTER allows to override existing
1032 NTF_ROUTER flag.
1033 NEIGH_UPDATE_F_ISROUTER indicates if the neighbour is known as
1034 a router.
1035
1036 Caller MUST hold reference count on the entry.
1037 */
1038
1039int neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new,
1040 u32 flags)
1041{
1042 u8 old;
1043 int err;
1044 int notify = 0;
1045 struct net_device *dev;
1046 int update_isrouter = 0;
1047
1048 write_lock_bh(&neigh->lock);
1049
1050 dev = neigh->dev;
1051 old = neigh->nud_state;
1052 err = -EPERM;
1053
1054 if (!(flags & NEIGH_UPDATE_F_ADMIN) &&
1055 (old & (NUD_NOARP | NUD_PERMANENT)))
1056 goto out;
1057
1058 if (!(new & NUD_VALID)) {
1059 neigh_del_timer(neigh);
1060 if (old & NUD_CONNECTED)
1061 neigh_suspect(neigh);
1062 neigh->nud_state = new;
1063 err = 0;
1064 notify = old & NUD_VALID;
1065 if ((old & (NUD_INCOMPLETE | NUD_PROBE)) &&
1066 (new & NUD_FAILED)) {
1067 neigh_invalidate(neigh);
1068 notify = 1;
1069 }
1070 goto out;
1071 }
1072
1073 /* Compare new lladdr with cached one */
1074 if (!dev->addr_len) {
1075 /* First case: device needs no address. */
1076 lladdr = neigh->ha;
1077 } else if (lladdr) {
1078 /* The second case: if something is already cached
1079 and a new address is proposed:
1080 - compare new & old
1081 - if they are different, check override flag
1082 */
1083 if ((old & NUD_VALID) &&
1084 !memcmp(lladdr, neigh->ha, dev->addr_len))
1085 lladdr = neigh->ha;
1086 } else {
1087 /* No address is supplied; if we know something,
1088 use it, otherwise discard the request.
1089 */
1090 err = -EINVAL;
1091 if (!(old & NUD_VALID))
1092 goto out;
1093 lladdr = neigh->ha;
1094 }
1095
1096 if (new & NUD_CONNECTED)
1097 neigh->confirmed = jiffies;
1098 neigh->updated = jiffies;
1099
1100 /* If entry was valid and address is not changed,
1101 do not change entry state, if new one is STALE.
1102 */
1103 err = 0;
1104 update_isrouter = flags & NEIGH_UPDATE_F_OVERRIDE_ISROUTER;
1105 if (old & NUD_VALID) {
1106 if (lladdr != neigh->ha && !(flags & NEIGH_UPDATE_F_OVERRIDE)) {
1107 update_isrouter = 0;
1108 if ((flags & NEIGH_UPDATE_F_WEAK_OVERRIDE) &&
1109 (old & NUD_CONNECTED)) {
1110 lladdr = neigh->ha;
1111 new = NUD_STALE;
1112 } else
1113 goto out;
1114 } else {
1115 if (lladdr == neigh->ha && new == NUD_STALE &&
1116 ((flags & NEIGH_UPDATE_F_WEAK_OVERRIDE) ||
1117 (old & NUD_CONNECTED))
1118 )
1119 new = old;
1120 }
1121 }
1122
1123 if (new != old) {
1124 neigh_del_timer(neigh);
1125 if (new & NUD_IN_TIMER)
1126 neigh_add_timer(neigh, (jiffies +
1127 ((new & NUD_REACHABLE) ?
1128 neigh->parms->reachable_time :
1129 0)));
1130 neigh->nud_state = new;
1131 }
1132
1133 if (lladdr != neigh->ha) {
1134 write_seqlock(&neigh->ha_lock);
1135 memcpy(&neigh->ha, lladdr, dev->addr_len);
1136 write_sequnlock(&neigh->ha_lock);
1137 neigh_update_hhs(neigh);
1138 if (!(new & NUD_CONNECTED))
1139 neigh->confirmed = jiffies -
1140 (neigh->parms->base_reachable_time << 1);
1141 notify = 1;
1142 }
1143 if (new == old)
1144 goto out;
1145 if (new & NUD_CONNECTED)
1146 neigh_connect(neigh);
1147 else
1148 neigh_suspect(neigh);
1149 if (!(old & NUD_VALID)) {
1150 struct sk_buff *skb;
1151
1152 /* Again: avoid dead loop if something went wrong */
1153
1154 while (neigh->nud_state & NUD_VALID &&
1155 (skb = __skb_dequeue(&neigh->arp_queue)) != NULL) {
1156 struct dst_entry *dst = skb_dst(skb);
1157 struct neighbour *n2, *n1 = neigh;
1158 write_unlock_bh(&neigh->lock);
1159 /* On shaper/eql skb->dst->neighbour != neigh :( */
1160 if (dst && (n2 = dst_get_neighbour(dst)) != NULL)
1161 n1 = n2;
1162 n1->output(n1, skb);
1163 write_lock_bh(&neigh->lock);
1164 }
1165 skb_queue_purge(&neigh->arp_queue);
1166 }
1167out:
1168 if (update_isrouter) {
1169 neigh->flags = (flags & NEIGH_UPDATE_F_ISROUTER) ?
1170 (neigh->flags | NTF_ROUTER) :
1171 (neigh->flags & ~NTF_ROUTER);
1172 }
1173 write_unlock_bh(&neigh->lock);
1174
1175 if (notify)
1176 neigh_update_notify(neigh);
1177
1178 return err;
1179}
1180EXPORT_SYMBOL(neigh_update);
1181
1182struct neighbour *neigh_event_ns(struct neigh_table *tbl,
1183 u8 *lladdr, void *saddr,
1184 struct net_device *dev)
1185{
1186 struct neighbour *neigh = __neigh_lookup(tbl, saddr, dev,
1187 lladdr || !dev->addr_len);
1188 if (neigh)
1189 neigh_update(neigh, lladdr, NUD_STALE,
1190 NEIGH_UPDATE_F_OVERRIDE);
1191 return neigh;
1192}
1193EXPORT_SYMBOL(neigh_event_ns);
1194
1195/* called with read_lock_bh(&n->lock); */
1196static void neigh_hh_init(struct neighbour *n, struct dst_entry *dst)
1197{
1198 struct net_device *dev = dst->dev;
1199 __be16 prot = dst->ops->protocol;
1200 struct hh_cache *hh = &n->hh;
1201
1202 write_lock_bh(&n->lock);
1203
1204 /* Only one thread can come in here and initialize the
1205 * hh_cache entry.
1206 */
1207 if (!hh->hh_len)
1208 dev->header_ops->cache(n, hh, prot);
1209
1210 write_unlock_bh(&n->lock);
1211}
1212
1213/* This function can be used in contexts, where only old dev_queue_xmit
1214 * worked, f.e. if you want to override normal output path (eql, shaper),
1215 * but resolution is not made yet.
1216 */
1217
1218int neigh_compat_output(struct neighbour *neigh, struct sk_buff *skb)
1219{
1220 struct net_device *dev = skb->dev;
1221
1222 __skb_pull(skb, skb_network_offset(skb));
1223
1224 if (dev_hard_header(skb, dev, ntohs(skb->protocol), NULL, NULL,
1225 skb->len) < 0 &&
1226 dev->header_ops->rebuild(skb))
1227 return 0;
1228
1229 return dev_queue_xmit(skb);
1230}
1231EXPORT_SYMBOL(neigh_compat_output);
1232
1233/* Slow and careful. */
1234
1235int neigh_resolve_output(struct neighbour *neigh, struct sk_buff *skb)
1236{
1237 struct dst_entry *dst = skb_dst(skb);
1238 int rc = 0;
1239
1240 if (!dst)
1241 goto discard;
1242
1243 __skb_pull(skb, skb_network_offset(skb));
1244
1245 if (!neigh_event_send(neigh, skb)) {
1246 int err;
1247 struct net_device *dev = neigh->dev;
1248 unsigned int seq;
1249
1250 if (dev->header_ops->cache && !neigh->hh.hh_len)
1251 neigh_hh_init(neigh, dst);
1252
1253 do {
1254 seq = read_seqbegin(&neigh->ha_lock);
1255 err = dev_hard_header(skb, dev, ntohs(skb->protocol),
1256 neigh->ha, NULL, skb->len);
1257 } while (read_seqretry(&neigh->ha_lock, seq));
1258
1259 if (err >= 0)
1260 rc = dev_queue_xmit(skb);
1261 else
1262 goto out_kfree_skb;
1263 }
1264out:
1265 return rc;
1266discard:
1267 NEIGH_PRINTK1("neigh_resolve_output: dst=%p neigh=%p\n",
1268 dst, neigh);
1269out_kfree_skb:
1270 rc = -EINVAL;
1271 kfree_skb(skb);
1272 goto out;
1273}
1274EXPORT_SYMBOL(neigh_resolve_output);
1275
1276/* As fast as possible without hh cache */
1277
1278int neigh_connected_output(struct neighbour *neigh, struct sk_buff *skb)
1279{
1280 struct net_device *dev = neigh->dev;
1281 unsigned int seq;
1282 int err;
1283
1284 __skb_pull(skb, skb_network_offset(skb));
1285
1286 do {
1287 seq = read_seqbegin(&neigh->ha_lock);
1288 err = dev_hard_header(skb, dev, ntohs(skb->protocol),
1289 neigh->ha, NULL, skb->len);
1290 } while (read_seqretry(&neigh->ha_lock, seq));
1291
1292 if (err >= 0)
1293 err = dev_queue_xmit(skb);
1294 else {
1295 err = -EINVAL;
1296 kfree_skb(skb);
1297 }
1298 return err;
1299}
1300EXPORT_SYMBOL(neigh_connected_output);
1301
1302int neigh_direct_output(struct neighbour *neigh, struct sk_buff *skb)
1303{
1304 return dev_queue_xmit(skb);
1305}
1306EXPORT_SYMBOL(neigh_direct_output);
1307
1308static void neigh_proxy_process(unsigned long arg)
1309{
1310 struct neigh_table *tbl = (struct neigh_table *)arg;
1311 long sched_next = 0;
1312 unsigned long now = jiffies;
1313 struct sk_buff *skb, *n;
1314
1315 spin_lock(&tbl->proxy_queue.lock);
1316
1317 skb_queue_walk_safe(&tbl->proxy_queue, skb, n) {
1318 long tdif = NEIGH_CB(skb)->sched_next - now;
1319
1320 if (tdif <= 0) {
1321 struct net_device *dev = skb->dev;
1322
1323 __skb_unlink(skb, &tbl->proxy_queue);
1324 if (tbl->proxy_redo && netif_running(dev)) {
1325 rcu_read_lock();
1326 tbl->proxy_redo(skb);
1327 rcu_read_unlock();
1328 } else {
1329 kfree_skb(skb);
1330 }
1331
1332 dev_put(dev);
1333 } else if (!sched_next || tdif < sched_next)
1334 sched_next = tdif;
1335 }
1336 del_timer(&tbl->proxy_timer);
1337 if (sched_next)
1338 mod_timer(&tbl->proxy_timer, jiffies + sched_next);
1339 spin_unlock(&tbl->proxy_queue.lock);
1340}
1341
1342void pneigh_enqueue(struct neigh_table *tbl, struct neigh_parms *p,
1343 struct sk_buff *skb)
1344{
1345 unsigned long now = jiffies;
1346 unsigned long sched_next = now + (net_random() % p->proxy_delay);
1347
1348 if (tbl->proxy_queue.qlen > p->proxy_qlen) {
1349 kfree_skb(skb);
1350 return;
1351 }
1352
1353 NEIGH_CB(skb)->sched_next = sched_next;
1354 NEIGH_CB(skb)->flags |= LOCALLY_ENQUEUED;
1355
1356 spin_lock(&tbl->proxy_queue.lock);
1357 if (del_timer(&tbl->proxy_timer)) {
1358 if (time_before(tbl->proxy_timer.expires, sched_next))
1359 sched_next = tbl->proxy_timer.expires;
1360 }
1361 skb_dst_drop(skb);
1362 dev_hold(skb->dev);
1363 __skb_queue_tail(&tbl->proxy_queue, skb);
1364 mod_timer(&tbl->proxy_timer, sched_next);
1365 spin_unlock(&tbl->proxy_queue.lock);
1366}
1367EXPORT_SYMBOL(pneigh_enqueue);
1368
1369static inline struct neigh_parms *lookup_neigh_parms(struct neigh_table *tbl,
1370 struct net *net, int ifindex)
1371{
1372 struct neigh_parms *p;
1373
1374 for (p = &tbl->parms; p; p = p->next) {
1375 if ((p->dev && p->dev->ifindex == ifindex && net_eq(neigh_parms_net(p), net)) ||
1376 (!p->dev && !ifindex))
1377 return p;
1378 }
1379
1380 return NULL;
1381}
1382
1383struct neigh_parms *neigh_parms_alloc(struct net_device *dev,
1384 struct neigh_table *tbl)
1385{
1386 struct neigh_parms *p, *ref;
1387 struct net *net = dev_net(dev);
1388 const struct net_device_ops *ops = dev->netdev_ops;
1389
1390 ref = lookup_neigh_parms(tbl, net, 0);
1391 if (!ref)
1392 return NULL;
1393
1394 p = kmemdup(ref, sizeof(*p), GFP_KERNEL);
1395 if (p) {
1396 p->tbl = tbl;
1397 atomic_set(&p->refcnt, 1);
1398 p->reachable_time =
1399 neigh_rand_reach_time(p->base_reachable_time);
1400
1401 if (ops->ndo_neigh_setup && ops->ndo_neigh_setup(dev, p)) {
1402 kfree(p);
1403 return NULL;
1404 }
1405
1406 dev_hold(dev);
1407 p->dev = dev;
1408 write_pnet(&p->net, hold_net(net));
1409 p->sysctl_table = NULL;
1410 write_lock_bh(&tbl->lock);
1411 p->next = tbl->parms.next;
1412 tbl->parms.next = p;
1413 write_unlock_bh(&tbl->lock);
1414 }
1415 return p;
1416}
1417EXPORT_SYMBOL(neigh_parms_alloc);
1418
1419static void neigh_rcu_free_parms(struct rcu_head *head)
1420{
1421 struct neigh_parms *parms =
1422 container_of(head, struct neigh_parms, rcu_head);
1423
1424 neigh_parms_put(parms);
1425}
1426
1427void neigh_parms_release(struct neigh_table *tbl, struct neigh_parms *parms)
1428{
1429 struct neigh_parms **p;
1430
1431 if (!parms || parms == &tbl->parms)
1432 return;
1433 write_lock_bh(&tbl->lock);
1434 for (p = &tbl->parms.next; *p; p = &(*p)->next) {
1435 if (*p == parms) {
1436 *p = parms->next;
1437 parms->dead = 1;
1438 write_unlock_bh(&tbl->lock);
1439 if (parms->dev)
1440 dev_put(parms->dev);
1441 call_rcu(&parms->rcu_head, neigh_rcu_free_parms);
1442 return;
1443 }
1444 }
1445 write_unlock_bh(&tbl->lock);
1446 NEIGH_PRINTK1("neigh_parms_release: not found\n");
1447}
1448EXPORT_SYMBOL(neigh_parms_release);
1449
1450static void neigh_parms_destroy(struct neigh_parms *parms)
1451{
1452 release_net(neigh_parms_net(parms));
1453 kfree(parms);
1454}
1455
1456static struct lock_class_key neigh_table_proxy_queue_class;
1457
1458void neigh_table_init_no_netlink(struct neigh_table *tbl)
1459{
1460 unsigned long now = jiffies;
1461 unsigned long phsize;
1462
1463 write_pnet(&tbl->parms.net, &init_net);
1464 atomic_set(&tbl->parms.refcnt, 1);
1465 tbl->parms.reachable_time =
1466 neigh_rand_reach_time(tbl->parms.base_reachable_time);
1467
1468 if (!tbl->kmem_cachep)
1469 tbl->kmem_cachep =
1470 kmem_cache_create(tbl->id, tbl->entry_size, 0,
1471 SLAB_HWCACHE_ALIGN|SLAB_PANIC,
1472 NULL);
1473 tbl->stats = alloc_percpu(struct neigh_statistics);
1474 if (!tbl->stats)
1475 panic("cannot create neighbour cache statistics");
1476
1477#ifdef CONFIG_PROC_FS
1478 if (!proc_create_data(tbl->id, 0, init_net.proc_net_stat,
1479 &neigh_stat_seq_fops, tbl))
1480 panic("cannot create neighbour proc dir entry");
1481#endif
1482
1483 RCU_INIT_POINTER(tbl->nht, neigh_hash_alloc(3));
1484
1485 phsize = (PNEIGH_HASHMASK + 1) * sizeof(struct pneigh_entry *);
1486 tbl->phash_buckets = kzalloc(phsize, GFP_KERNEL);
1487
1488 if (!tbl->nht || !tbl->phash_buckets)
1489 panic("cannot allocate neighbour cache hashes");
1490
1491 rwlock_init(&tbl->lock);
1492 INIT_DELAYED_WORK_DEFERRABLE(&tbl->gc_work, neigh_periodic_work);
1493 schedule_delayed_work(&tbl->gc_work, tbl->parms.reachable_time);
1494 setup_timer(&tbl->proxy_timer, neigh_proxy_process, (unsigned long)tbl);
1495 skb_queue_head_init_class(&tbl->proxy_queue,
1496 &neigh_table_proxy_queue_class);
1497
1498 tbl->last_flush = now;
1499 tbl->last_rand = now + tbl->parms.reachable_time * 20;
1500}
1501EXPORT_SYMBOL(neigh_table_init_no_netlink);
1502
1503void neigh_table_init(struct neigh_table *tbl)
1504{
1505 struct neigh_table *tmp;
1506
1507 neigh_table_init_no_netlink(tbl);
1508 write_lock(&neigh_tbl_lock);
1509 for (tmp = neigh_tables; tmp; tmp = tmp->next) {
1510 if (tmp->family == tbl->family)
1511 break;
1512 }
1513 tbl->next = neigh_tables;
1514 neigh_tables = tbl;
1515 write_unlock(&neigh_tbl_lock);
1516
1517 if (unlikely(tmp)) {
1518 printk(KERN_ERR "NEIGH: Registering multiple tables for "
1519 "family %d\n", tbl->family);
1520 dump_stack();
1521 }
1522}
1523EXPORT_SYMBOL(neigh_table_init);
1524
1525int neigh_table_clear(struct neigh_table *tbl)
1526{
1527 struct neigh_table **tp;
1528
1529 /* It is not clean... Fix it to unload IPv6 module safely */
1530 cancel_delayed_work_sync(&tbl->gc_work);
1531 del_timer_sync(&tbl->proxy_timer);
1532 pneigh_queue_purge(&tbl->proxy_queue);
1533 neigh_ifdown(tbl, NULL);
1534 if (atomic_read(&tbl->entries))
1535 printk(KERN_CRIT "neighbour leakage\n");
1536 write_lock(&neigh_tbl_lock);
1537 for (tp = &neigh_tables; *tp; tp = &(*tp)->next) {
1538 if (*tp == tbl) {
1539 *tp = tbl->next;
1540 break;
1541 }
1542 }
1543 write_unlock(&neigh_tbl_lock);
1544
1545 call_rcu(&rcu_dereference_protected(tbl->nht, 1)->rcu,
1546 neigh_hash_free_rcu);
1547 tbl->nht = NULL;
1548
1549 kfree(tbl->phash_buckets);
1550 tbl->phash_buckets = NULL;
1551
1552 remove_proc_entry(tbl->id, init_net.proc_net_stat);
1553
1554 free_percpu(tbl->stats);
1555 tbl->stats = NULL;
1556
1557 kmem_cache_destroy(tbl->kmem_cachep);
1558 tbl->kmem_cachep = NULL;
1559
1560 return 0;
1561}
1562EXPORT_SYMBOL(neigh_table_clear);
1563
1564static int neigh_delete(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
1565{
1566 struct net *net = sock_net(skb->sk);
1567 struct ndmsg *ndm;
1568 struct nlattr *dst_attr;
1569 struct neigh_table *tbl;
1570 struct net_device *dev = NULL;
1571 int err = -EINVAL;
1572
1573 ASSERT_RTNL();
1574 if (nlmsg_len(nlh) < sizeof(*ndm))
1575 goto out;
1576
1577 dst_attr = nlmsg_find_attr(nlh, sizeof(*ndm), NDA_DST);
1578 if (dst_attr == NULL)
1579 goto out;
1580
1581 ndm = nlmsg_data(nlh);
1582 if (ndm->ndm_ifindex) {
1583 dev = __dev_get_by_index(net, ndm->ndm_ifindex);
1584 if (dev == NULL) {
1585 err = -ENODEV;
1586 goto out;
1587 }
1588 }
1589
1590 read_lock(&neigh_tbl_lock);
1591 for (tbl = neigh_tables; tbl; tbl = tbl->next) {
1592 struct neighbour *neigh;
1593
1594 if (tbl->family != ndm->ndm_family)
1595 continue;
1596 read_unlock(&neigh_tbl_lock);
1597
1598 if (nla_len(dst_attr) < tbl->key_len)
1599 goto out;
1600
1601 if (ndm->ndm_flags & NTF_PROXY) {
1602 err = pneigh_delete(tbl, net, nla_data(dst_attr), dev);
1603 goto out;
1604 }
1605
1606 if (dev == NULL)
1607 goto out;
1608
1609 neigh = neigh_lookup(tbl, nla_data(dst_attr), dev);
1610 if (neigh == NULL) {
1611 err = -ENOENT;
1612 goto out;
1613 }
1614
1615 err = neigh_update(neigh, NULL, NUD_FAILED,
1616 NEIGH_UPDATE_F_OVERRIDE |
1617 NEIGH_UPDATE_F_ADMIN);
1618 neigh_release(neigh);
1619 goto out;
1620 }
1621 read_unlock(&neigh_tbl_lock);
1622 err = -EAFNOSUPPORT;
1623
1624out:
1625 return err;
1626}
1627
1628static int neigh_add(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
1629{
1630 struct net *net = sock_net(skb->sk);
1631 struct ndmsg *ndm;
1632 struct nlattr *tb[NDA_MAX+1];
1633 struct neigh_table *tbl;
1634 struct net_device *dev = NULL;
1635 int err;
1636
1637 ASSERT_RTNL();
1638 err = nlmsg_parse(nlh, sizeof(*ndm), tb, NDA_MAX, NULL);
1639 if (err < 0)
1640 goto out;
1641
1642 err = -EINVAL;
1643 if (tb[NDA_DST] == NULL)
1644 goto out;
1645
1646 ndm = nlmsg_data(nlh);
1647 if (ndm->ndm_ifindex) {
1648 dev = __dev_get_by_index(net, ndm->ndm_ifindex);
1649 if (dev == NULL) {
1650 err = -ENODEV;
1651 goto out;
1652 }
1653
1654 if (tb[NDA_LLADDR] && nla_len(tb[NDA_LLADDR]) < dev->addr_len)
1655 goto out;
1656 }
1657
1658 read_lock(&neigh_tbl_lock);
1659 for (tbl = neigh_tables; tbl; tbl = tbl->next) {
1660 int flags = NEIGH_UPDATE_F_ADMIN | NEIGH_UPDATE_F_OVERRIDE;
1661 struct neighbour *neigh;
1662 void *dst, *lladdr;
1663
1664 if (tbl->family != ndm->ndm_family)
1665 continue;
1666 read_unlock(&neigh_tbl_lock);
1667
1668 if (nla_len(tb[NDA_DST]) < tbl->key_len)
1669 goto out;
1670 dst = nla_data(tb[NDA_DST]);
1671 lladdr = tb[NDA_LLADDR] ? nla_data(tb[NDA_LLADDR]) : NULL;
1672
1673 if (ndm->ndm_flags & NTF_PROXY) {
1674 struct pneigh_entry *pn;
1675
1676 err = -ENOBUFS;
1677 pn = pneigh_lookup(tbl, net, dst, dev, 1);
1678 if (pn) {
1679 pn->flags = ndm->ndm_flags;
1680 err = 0;
1681 }
1682 goto out;
1683 }
1684
1685 if (dev == NULL)
1686 goto out;
1687
1688 neigh = neigh_lookup(tbl, dst, dev);
1689 if (neigh == NULL) {
1690 if (!(nlh->nlmsg_flags & NLM_F_CREATE)) {
1691 err = -ENOENT;
1692 goto out;
1693 }
1694
1695 neigh = __neigh_lookup_errno(tbl, dst, dev);
1696 if (IS_ERR(neigh)) {
1697 err = PTR_ERR(neigh);
1698 goto out;
1699 }
1700 } else {
1701 if (nlh->nlmsg_flags & NLM_F_EXCL) {
1702 err = -EEXIST;
1703 neigh_release(neigh);
1704 goto out;
1705 }
1706
1707 if (!(nlh->nlmsg_flags & NLM_F_REPLACE))
1708 flags &= ~NEIGH_UPDATE_F_OVERRIDE;
1709 }
1710
1711 if (ndm->ndm_flags & NTF_USE) {
1712 neigh_event_send(neigh, NULL);
1713 err = 0;
1714 } else
1715 err = neigh_update(neigh, lladdr, ndm->ndm_state, flags);
1716 neigh_release(neigh);
1717 goto out;
1718 }
1719
1720 read_unlock(&neigh_tbl_lock);
1721 err = -EAFNOSUPPORT;
1722out:
1723 return err;
1724}
1725
1726static int neightbl_fill_parms(struct sk_buff *skb, struct neigh_parms *parms)
1727{
1728 struct nlattr *nest;
1729
1730 nest = nla_nest_start(skb, NDTA_PARMS);
1731 if (nest == NULL)
1732 return -ENOBUFS;
1733
1734 if (parms->dev)
1735 NLA_PUT_U32(skb, NDTPA_IFINDEX, parms->dev->ifindex);
1736
1737 NLA_PUT_U32(skb, NDTPA_REFCNT, atomic_read(&parms->refcnt));
1738 NLA_PUT_U32(skb, NDTPA_QUEUE_LEN, parms->queue_len);
1739 NLA_PUT_U32(skb, NDTPA_PROXY_QLEN, parms->proxy_qlen);
1740 NLA_PUT_U32(skb, NDTPA_APP_PROBES, parms->app_probes);
1741 NLA_PUT_U32(skb, NDTPA_UCAST_PROBES, parms->ucast_probes);
1742 NLA_PUT_U32(skb, NDTPA_MCAST_PROBES, parms->mcast_probes);
1743 NLA_PUT_MSECS(skb, NDTPA_REACHABLE_TIME, parms->reachable_time);
1744 NLA_PUT_MSECS(skb, NDTPA_BASE_REACHABLE_TIME,
1745 parms->base_reachable_time);
1746 NLA_PUT_MSECS(skb, NDTPA_GC_STALETIME, parms->gc_staletime);
1747 NLA_PUT_MSECS(skb, NDTPA_DELAY_PROBE_TIME, parms->delay_probe_time);
1748 NLA_PUT_MSECS(skb, NDTPA_RETRANS_TIME, parms->retrans_time);
1749 NLA_PUT_MSECS(skb, NDTPA_ANYCAST_DELAY, parms->anycast_delay);
1750 NLA_PUT_MSECS(skb, NDTPA_PROXY_DELAY, parms->proxy_delay);
1751 NLA_PUT_MSECS(skb, NDTPA_LOCKTIME, parms->locktime);
1752
1753 return nla_nest_end(skb, nest);
1754
1755nla_put_failure:
1756 nla_nest_cancel(skb, nest);
1757 return -EMSGSIZE;
1758}
1759
1760static int neightbl_fill_info(struct sk_buff *skb, struct neigh_table *tbl,
1761 u32 pid, u32 seq, int type, int flags)
1762{
1763 struct nlmsghdr *nlh;
1764 struct ndtmsg *ndtmsg;
1765
1766 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndtmsg), flags);
1767 if (nlh == NULL)
1768 return -EMSGSIZE;
1769
1770 ndtmsg = nlmsg_data(nlh);
1771
1772 read_lock_bh(&tbl->lock);
1773 ndtmsg->ndtm_family = tbl->family;
1774 ndtmsg->ndtm_pad1 = 0;
1775 ndtmsg->ndtm_pad2 = 0;
1776
1777 NLA_PUT_STRING(skb, NDTA_NAME, tbl->id);
1778 NLA_PUT_MSECS(skb, NDTA_GC_INTERVAL, tbl->gc_interval);
1779 NLA_PUT_U32(skb, NDTA_THRESH1, tbl->gc_thresh1);
1780 NLA_PUT_U32(skb, NDTA_THRESH2, tbl->gc_thresh2);
1781 NLA_PUT_U32(skb, NDTA_THRESH3, tbl->gc_thresh3);
1782
1783 {
1784 unsigned long now = jiffies;
1785 unsigned int flush_delta = now - tbl->last_flush;
1786 unsigned int rand_delta = now - tbl->last_rand;
1787 struct neigh_hash_table *nht;
1788 struct ndt_config ndc = {
1789 .ndtc_key_len = tbl->key_len,
1790 .ndtc_entry_size = tbl->entry_size,
1791 .ndtc_entries = atomic_read(&tbl->entries),
1792 .ndtc_last_flush = jiffies_to_msecs(flush_delta),
1793 .ndtc_last_rand = jiffies_to_msecs(rand_delta),
1794 .ndtc_proxy_qlen = tbl->proxy_queue.qlen,
1795 };
1796
1797 rcu_read_lock_bh();
1798 nht = rcu_dereference_bh(tbl->nht);
1799 ndc.ndtc_hash_rnd = nht->hash_rnd;
1800 ndc.ndtc_hash_mask = ((1 << nht->hash_shift) - 1);
1801 rcu_read_unlock_bh();
1802
1803 NLA_PUT(skb, NDTA_CONFIG, sizeof(ndc), &ndc);
1804 }
1805
1806 {
1807 int cpu;
1808 struct ndt_stats ndst;
1809
1810 memset(&ndst, 0, sizeof(ndst));
1811
1812 for_each_possible_cpu(cpu) {
1813 struct neigh_statistics *st;
1814
1815 st = per_cpu_ptr(tbl->stats, cpu);
1816 ndst.ndts_allocs += st->allocs;
1817 ndst.ndts_destroys += st->destroys;
1818 ndst.ndts_hash_grows += st->hash_grows;
1819 ndst.ndts_res_failed += st->res_failed;
1820 ndst.ndts_lookups += st->lookups;
1821 ndst.ndts_hits += st->hits;
1822 ndst.ndts_rcv_probes_mcast += st->rcv_probes_mcast;
1823 ndst.ndts_rcv_probes_ucast += st->rcv_probes_ucast;
1824 ndst.ndts_periodic_gc_runs += st->periodic_gc_runs;
1825 ndst.ndts_forced_gc_runs += st->forced_gc_runs;
1826 }
1827
1828 NLA_PUT(skb, NDTA_STATS, sizeof(ndst), &ndst);
1829 }
1830
1831 BUG_ON(tbl->parms.dev);
1832 if (neightbl_fill_parms(skb, &tbl->parms) < 0)
1833 goto nla_put_failure;
1834
1835 read_unlock_bh(&tbl->lock);
1836 return nlmsg_end(skb, nlh);
1837
1838nla_put_failure:
1839 read_unlock_bh(&tbl->lock);
1840 nlmsg_cancel(skb, nlh);
1841 return -EMSGSIZE;
1842}
1843
1844static int neightbl_fill_param_info(struct sk_buff *skb,
1845 struct neigh_table *tbl,
1846 struct neigh_parms *parms,
1847 u32 pid, u32 seq, int type,
1848 unsigned int flags)
1849{
1850 struct ndtmsg *ndtmsg;
1851 struct nlmsghdr *nlh;
1852
1853 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndtmsg), flags);
1854 if (nlh == NULL)
1855 return -EMSGSIZE;
1856
1857 ndtmsg = nlmsg_data(nlh);
1858
1859 read_lock_bh(&tbl->lock);
1860 ndtmsg->ndtm_family = tbl->family;
1861 ndtmsg->ndtm_pad1 = 0;
1862 ndtmsg->ndtm_pad2 = 0;
1863
1864 if (nla_put_string(skb, NDTA_NAME, tbl->id) < 0 ||
1865 neightbl_fill_parms(skb, parms) < 0)
1866 goto errout;
1867
1868 read_unlock_bh(&tbl->lock);
1869 return nlmsg_end(skb, nlh);
1870errout:
1871 read_unlock_bh(&tbl->lock);
1872 nlmsg_cancel(skb, nlh);
1873 return -EMSGSIZE;
1874}
1875
1876static const struct nla_policy nl_neightbl_policy[NDTA_MAX+1] = {
1877 [NDTA_NAME] = { .type = NLA_STRING },
1878 [NDTA_THRESH1] = { .type = NLA_U32 },
1879 [NDTA_THRESH2] = { .type = NLA_U32 },
1880 [NDTA_THRESH3] = { .type = NLA_U32 },
1881 [NDTA_GC_INTERVAL] = { .type = NLA_U64 },
1882 [NDTA_PARMS] = { .type = NLA_NESTED },
1883};
1884
1885static const struct nla_policy nl_ntbl_parm_policy[NDTPA_MAX+1] = {
1886 [NDTPA_IFINDEX] = { .type = NLA_U32 },
1887 [NDTPA_QUEUE_LEN] = { .type = NLA_U32 },
1888 [NDTPA_PROXY_QLEN] = { .type = NLA_U32 },
1889 [NDTPA_APP_PROBES] = { .type = NLA_U32 },
1890 [NDTPA_UCAST_PROBES] = { .type = NLA_U32 },
1891 [NDTPA_MCAST_PROBES] = { .type = NLA_U32 },
1892 [NDTPA_BASE_REACHABLE_TIME] = { .type = NLA_U64 },
1893 [NDTPA_GC_STALETIME] = { .type = NLA_U64 },
1894 [NDTPA_DELAY_PROBE_TIME] = { .type = NLA_U64 },
1895 [NDTPA_RETRANS_TIME] = { .type = NLA_U64 },
1896 [NDTPA_ANYCAST_DELAY] = { .type = NLA_U64 },
1897 [NDTPA_PROXY_DELAY] = { .type = NLA_U64 },
1898 [NDTPA_LOCKTIME] = { .type = NLA_U64 },
1899};
1900
1901static int neightbl_set(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
1902{
1903 struct net *net = sock_net(skb->sk);
1904 struct neigh_table *tbl;
1905 struct ndtmsg *ndtmsg;
1906 struct nlattr *tb[NDTA_MAX+1];
1907 int err;
1908
1909 err = nlmsg_parse(nlh, sizeof(*ndtmsg), tb, NDTA_MAX,
1910 nl_neightbl_policy);
1911 if (err < 0)
1912 goto errout;
1913
1914 if (tb[NDTA_NAME] == NULL) {
1915 err = -EINVAL;
1916 goto errout;
1917 }
1918
1919 ndtmsg = nlmsg_data(nlh);
1920 read_lock(&neigh_tbl_lock);
1921 for (tbl = neigh_tables; tbl; tbl = tbl->next) {
1922 if (ndtmsg->ndtm_family && tbl->family != ndtmsg->ndtm_family)
1923 continue;
1924
1925 if (nla_strcmp(tb[NDTA_NAME], tbl->id) == 0)
1926 break;
1927 }
1928
1929 if (tbl == NULL) {
1930 err = -ENOENT;
1931 goto errout_locked;
1932 }
1933
1934 /*
1935 * We acquire tbl->lock to be nice to the periodic timers and
1936 * make sure they always see a consistent set of values.
1937 */
1938 write_lock_bh(&tbl->lock);
1939
1940 if (tb[NDTA_PARMS]) {
1941 struct nlattr *tbp[NDTPA_MAX+1];
1942 struct neigh_parms *p;
1943 int i, ifindex = 0;
1944
1945 err = nla_parse_nested(tbp, NDTPA_MAX, tb[NDTA_PARMS],
1946 nl_ntbl_parm_policy);
1947 if (err < 0)
1948 goto errout_tbl_lock;
1949
1950 if (tbp[NDTPA_IFINDEX])
1951 ifindex = nla_get_u32(tbp[NDTPA_IFINDEX]);
1952
1953 p = lookup_neigh_parms(tbl, net, ifindex);
1954 if (p == NULL) {
1955 err = -ENOENT;
1956 goto errout_tbl_lock;
1957 }
1958
1959 for (i = 1; i <= NDTPA_MAX; i++) {
1960 if (tbp[i] == NULL)
1961 continue;
1962
1963 switch (i) {
1964 case NDTPA_QUEUE_LEN:
1965 p->queue_len = nla_get_u32(tbp[i]);
1966 break;
1967 case NDTPA_PROXY_QLEN:
1968 p->proxy_qlen = nla_get_u32(tbp[i]);
1969 break;
1970 case NDTPA_APP_PROBES:
1971 p->app_probes = nla_get_u32(tbp[i]);
1972 break;
1973 case NDTPA_UCAST_PROBES:
1974 p->ucast_probes = nla_get_u32(tbp[i]);
1975 break;
1976 case NDTPA_MCAST_PROBES:
1977 p->mcast_probes = nla_get_u32(tbp[i]);
1978 break;
1979 case NDTPA_BASE_REACHABLE_TIME:
1980 p->base_reachable_time = nla_get_msecs(tbp[i]);
1981 break;
1982 case NDTPA_GC_STALETIME:
1983 p->gc_staletime = nla_get_msecs(tbp[i]);
1984 break;
1985 case NDTPA_DELAY_PROBE_TIME:
1986 p->delay_probe_time = nla_get_msecs(tbp[i]);
1987 break;
1988 case NDTPA_RETRANS_TIME:
1989 p->retrans_time = nla_get_msecs(tbp[i]);
1990 break;
1991 case NDTPA_ANYCAST_DELAY:
1992 p->anycast_delay = nla_get_msecs(tbp[i]);
1993 break;
1994 case NDTPA_PROXY_DELAY:
1995 p->proxy_delay = nla_get_msecs(tbp[i]);
1996 break;
1997 case NDTPA_LOCKTIME:
1998 p->locktime = nla_get_msecs(tbp[i]);
1999 break;
2000 }
2001 }
2002 }
2003
2004 if (tb[NDTA_THRESH1])
2005 tbl->gc_thresh1 = nla_get_u32(tb[NDTA_THRESH1]);
2006
2007 if (tb[NDTA_THRESH2])
2008 tbl->gc_thresh2 = nla_get_u32(tb[NDTA_THRESH2]);
2009
2010 if (tb[NDTA_THRESH3])
2011 tbl->gc_thresh3 = nla_get_u32(tb[NDTA_THRESH3]);
2012
2013 if (tb[NDTA_GC_INTERVAL])
2014 tbl->gc_interval = nla_get_msecs(tb[NDTA_GC_INTERVAL]);
2015
2016 err = 0;
2017
2018errout_tbl_lock:
2019 write_unlock_bh(&tbl->lock);
2020errout_locked:
2021 read_unlock(&neigh_tbl_lock);
2022errout:
2023 return err;
2024}
2025
2026static int neightbl_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
2027{
2028 struct net *net = sock_net(skb->sk);
2029 int family, tidx, nidx = 0;
2030 int tbl_skip = cb->args[0];
2031 int neigh_skip = cb->args[1];
2032 struct neigh_table *tbl;
2033
2034 family = ((struct rtgenmsg *) nlmsg_data(cb->nlh))->rtgen_family;
2035
2036 read_lock(&neigh_tbl_lock);
2037 for (tbl = neigh_tables, tidx = 0; tbl; tbl = tbl->next, tidx++) {
2038 struct neigh_parms *p;
2039
2040 if (tidx < tbl_skip || (family && tbl->family != family))
2041 continue;
2042
2043 if (neightbl_fill_info(skb, tbl, NETLINK_CB(cb->skb).pid,
2044 cb->nlh->nlmsg_seq, RTM_NEWNEIGHTBL,
2045 NLM_F_MULTI) <= 0)
2046 break;
2047
2048 for (nidx = 0, p = tbl->parms.next; p; p = p->next) {
2049 if (!net_eq(neigh_parms_net(p), net))
2050 continue;
2051
2052 if (nidx < neigh_skip)
2053 goto next;
2054
2055 if (neightbl_fill_param_info(skb, tbl, p,
2056 NETLINK_CB(cb->skb).pid,
2057 cb->nlh->nlmsg_seq,
2058 RTM_NEWNEIGHTBL,
2059 NLM_F_MULTI) <= 0)
2060 goto out;
2061 next:
2062 nidx++;
2063 }
2064
2065 neigh_skip = 0;
2066 }
2067out:
2068 read_unlock(&neigh_tbl_lock);
2069 cb->args[0] = tidx;
2070 cb->args[1] = nidx;
2071
2072 return skb->len;
2073}
2074
2075static int neigh_fill_info(struct sk_buff *skb, struct neighbour *neigh,
2076 u32 pid, u32 seq, int type, unsigned int flags)
2077{
2078 unsigned long now = jiffies;
2079 struct nda_cacheinfo ci;
2080 struct nlmsghdr *nlh;
2081 struct ndmsg *ndm;
2082
2083 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndm), flags);
2084 if (nlh == NULL)
2085 return -EMSGSIZE;
2086
2087 ndm = nlmsg_data(nlh);
2088 ndm->ndm_family = neigh->ops->family;
2089 ndm->ndm_pad1 = 0;
2090 ndm->ndm_pad2 = 0;
2091 ndm->ndm_flags = neigh->flags;
2092 ndm->ndm_type = neigh->type;
2093 ndm->ndm_ifindex = neigh->dev->ifindex;
2094
2095 NLA_PUT(skb, NDA_DST, neigh->tbl->key_len, neigh->primary_key);
2096
2097 read_lock_bh(&neigh->lock);
2098 ndm->ndm_state = neigh->nud_state;
2099 if (neigh->nud_state & NUD_VALID) {
2100 char haddr[MAX_ADDR_LEN];
2101
2102 neigh_ha_snapshot(haddr, neigh, neigh->dev);
2103 if (nla_put(skb, NDA_LLADDR, neigh->dev->addr_len, haddr) < 0) {
2104 read_unlock_bh(&neigh->lock);
2105 goto nla_put_failure;
2106 }
2107 }
2108
2109 ci.ndm_used = jiffies_to_clock_t(now - neigh->used);
2110 ci.ndm_confirmed = jiffies_to_clock_t(now - neigh->confirmed);
2111 ci.ndm_updated = jiffies_to_clock_t(now - neigh->updated);
2112 ci.ndm_refcnt = atomic_read(&neigh->refcnt) - 1;
2113 read_unlock_bh(&neigh->lock);
2114
2115 NLA_PUT_U32(skb, NDA_PROBES, atomic_read(&neigh->probes));
2116 NLA_PUT(skb, NDA_CACHEINFO, sizeof(ci), &ci);
2117
2118 return nlmsg_end(skb, nlh);
2119
2120nla_put_failure:
2121 nlmsg_cancel(skb, nlh);
2122 return -EMSGSIZE;
2123}
2124
2125static void neigh_update_notify(struct neighbour *neigh)
2126{
2127 call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, neigh);
2128 __neigh_notify(neigh, RTM_NEWNEIGH, 0);
2129}
2130
2131static int neigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb,
2132 struct netlink_callback *cb)
2133{
2134 struct net *net = sock_net(skb->sk);
2135 struct neighbour *n;
2136 int rc, h, s_h = cb->args[1];
2137 int idx, s_idx = idx = cb->args[2];
2138 struct neigh_hash_table *nht;
2139
2140 rcu_read_lock_bh();
2141 nht = rcu_dereference_bh(tbl->nht);
2142
2143 for (h = 0; h < (1 << nht->hash_shift); h++) {
2144 if (h < s_h)
2145 continue;
2146 if (h > s_h)
2147 s_idx = 0;
2148 for (n = rcu_dereference_bh(nht->hash_buckets[h]), idx = 0;
2149 n != NULL;
2150 n = rcu_dereference_bh(n->next)) {
2151 if (!net_eq(dev_net(n->dev), net))
2152 continue;
2153 if (idx < s_idx)
2154 goto next;
2155 if (neigh_fill_info(skb, n, NETLINK_CB(cb->skb).pid,
2156 cb->nlh->nlmsg_seq,
2157 RTM_NEWNEIGH,
2158 NLM_F_MULTI) <= 0) {
2159 rc = -1;
2160 goto out;
2161 }
2162next:
2163 idx++;
2164 }
2165 }
2166 rc = skb->len;
2167out:
2168 rcu_read_unlock_bh();
2169 cb->args[1] = h;
2170 cb->args[2] = idx;
2171 return rc;
2172}
2173
2174static int neigh_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
2175{
2176 struct neigh_table *tbl;
2177 int t, family, s_t;
2178
2179 read_lock(&neigh_tbl_lock);
2180 family = ((struct rtgenmsg *) nlmsg_data(cb->nlh))->rtgen_family;
2181 s_t = cb->args[0];
2182
2183 for (tbl = neigh_tables, t = 0; tbl; tbl = tbl->next, t++) {
2184 if (t < s_t || (family && tbl->family != family))
2185 continue;
2186 if (t > s_t)
2187 memset(&cb->args[1], 0, sizeof(cb->args) -
2188 sizeof(cb->args[0]));
2189 if (neigh_dump_table(tbl, skb, cb) < 0)
2190 break;
2191 }
2192 read_unlock(&neigh_tbl_lock);
2193
2194 cb->args[0] = t;
2195 return skb->len;
2196}
2197
2198void neigh_for_each(struct neigh_table *tbl, void (*cb)(struct neighbour *, void *), void *cookie)
2199{
2200 int chain;
2201 struct neigh_hash_table *nht;
2202
2203 rcu_read_lock_bh();
2204 nht = rcu_dereference_bh(tbl->nht);
2205
2206 read_lock(&tbl->lock); /* avoid resizes */
2207 for (chain = 0; chain < (1 << nht->hash_shift); chain++) {
2208 struct neighbour *n;
2209
2210 for (n = rcu_dereference_bh(nht->hash_buckets[chain]);
2211 n != NULL;
2212 n = rcu_dereference_bh(n->next))
2213 cb(n, cookie);
2214 }
2215 read_unlock(&tbl->lock);
2216 rcu_read_unlock_bh();
2217}
2218EXPORT_SYMBOL(neigh_for_each);
2219
2220/* The tbl->lock must be held as a writer and BH disabled. */
2221void __neigh_for_each_release(struct neigh_table *tbl,
2222 int (*cb)(struct neighbour *))
2223{
2224 int chain;
2225 struct neigh_hash_table *nht;
2226
2227 nht = rcu_dereference_protected(tbl->nht,
2228 lockdep_is_held(&tbl->lock));
2229 for (chain = 0; chain < (1 << nht->hash_shift); chain++) {
2230 struct neighbour *n;
2231 struct neighbour __rcu **np;
2232
2233 np = &nht->hash_buckets[chain];
2234 while ((n = rcu_dereference_protected(*np,
2235 lockdep_is_held(&tbl->lock))) != NULL) {
2236 int release;
2237
2238 write_lock(&n->lock);
2239 release = cb(n);
2240 if (release) {
2241 rcu_assign_pointer(*np,
2242 rcu_dereference_protected(n->next,
2243 lockdep_is_held(&tbl->lock)));
2244 n->dead = 1;
2245 } else
2246 np = &n->next;
2247 write_unlock(&n->lock);
2248 if (release)
2249 neigh_cleanup_and_release(n);
2250 }
2251 }
2252}
2253EXPORT_SYMBOL(__neigh_for_each_release);
2254
2255#ifdef CONFIG_PROC_FS
2256
2257static struct neighbour *neigh_get_first(struct seq_file *seq)
2258{
2259 struct neigh_seq_state *state = seq->private;
2260 struct net *net = seq_file_net(seq);
2261 struct neigh_hash_table *nht = state->nht;
2262 struct neighbour *n = NULL;
2263 int bucket = state->bucket;
2264
2265 state->flags &= ~NEIGH_SEQ_IS_PNEIGH;
2266 for (bucket = 0; bucket < (1 << nht->hash_shift); bucket++) {
2267 n = rcu_dereference_bh(nht->hash_buckets[bucket]);
2268
2269 while (n) {
2270 if (!net_eq(dev_net(n->dev), net))
2271 goto next;
2272 if (state->neigh_sub_iter) {
2273 loff_t fakep = 0;
2274 void *v;
2275
2276 v = state->neigh_sub_iter(state, n, &fakep);
2277 if (!v)
2278 goto next;
2279 }
2280 if (!(state->flags & NEIGH_SEQ_SKIP_NOARP))
2281 break;
2282 if (n->nud_state & ~NUD_NOARP)
2283 break;
2284next:
2285 n = rcu_dereference_bh(n->next);
2286 }
2287
2288 if (n)
2289 break;
2290 }
2291 state->bucket = bucket;
2292
2293 return n;
2294}
2295
2296static struct neighbour *neigh_get_next(struct seq_file *seq,
2297 struct neighbour *n,
2298 loff_t *pos)
2299{
2300 struct neigh_seq_state *state = seq->private;
2301 struct net *net = seq_file_net(seq);
2302 struct neigh_hash_table *nht = state->nht;
2303
2304 if (state->neigh_sub_iter) {
2305 void *v = state->neigh_sub_iter(state, n, pos);
2306 if (v)
2307 return n;
2308 }
2309 n = rcu_dereference_bh(n->next);
2310
2311 while (1) {
2312 while (n) {
2313 if (!net_eq(dev_net(n->dev), net))
2314 goto next;
2315 if (state->neigh_sub_iter) {
2316 void *v = state->neigh_sub_iter(state, n, pos);
2317 if (v)
2318 return n;
2319 goto next;
2320 }
2321 if (!(state->flags & NEIGH_SEQ_SKIP_NOARP))
2322 break;
2323
2324 if (n->nud_state & ~NUD_NOARP)
2325 break;
2326next:
2327 n = rcu_dereference_bh(n->next);
2328 }
2329
2330 if (n)
2331 break;
2332
2333 if (++state->bucket >= (1 << nht->hash_shift))
2334 break;
2335
2336 n = rcu_dereference_bh(nht->hash_buckets[state->bucket]);
2337 }
2338
2339 if (n && pos)
2340 --(*pos);
2341 return n;
2342}
2343
2344static struct neighbour *neigh_get_idx(struct seq_file *seq, loff_t *pos)
2345{
2346 struct neighbour *n = neigh_get_first(seq);
2347
2348 if (n) {
2349 --(*pos);
2350 while (*pos) {
2351 n = neigh_get_next(seq, n, pos);
2352 if (!n)
2353 break;
2354 }
2355 }
2356 return *pos ? NULL : n;
2357}
2358
2359static struct pneigh_entry *pneigh_get_first(struct seq_file *seq)
2360{
2361 struct neigh_seq_state *state = seq->private;
2362 struct net *net = seq_file_net(seq);
2363 struct neigh_table *tbl = state->tbl;
2364 struct pneigh_entry *pn = NULL;
2365 int bucket = state->bucket;
2366
2367 state->flags |= NEIGH_SEQ_IS_PNEIGH;
2368 for (bucket = 0; bucket <= PNEIGH_HASHMASK; bucket++) {
2369 pn = tbl->phash_buckets[bucket];
2370 while (pn && !net_eq(pneigh_net(pn), net))
2371 pn = pn->next;
2372 if (pn)
2373 break;
2374 }
2375 state->bucket = bucket;
2376
2377 return pn;
2378}
2379
2380static struct pneigh_entry *pneigh_get_next(struct seq_file *seq,
2381 struct pneigh_entry *pn,
2382 loff_t *pos)
2383{
2384 struct neigh_seq_state *state = seq->private;
2385 struct net *net = seq_file_net(seq);
2386 struct neigh_table *tbl = state->tbl;
2387
2388 pn = pn->next;
2389 while (!pn) {
2390 if (++state->bucket > PNEIGH_HASHMASK)
2391 break;
2392 pn = tbl->phash_buckets[state->bucket];
2393 while (pn && !net_eq(pneigh_net(pn), net))
2394 pn = pn->next;
2395 if (pn)
2396 break;
2397 }
2398
2399 if (pn && pos)
2400 --(*pos);
2401
2402 return pn;
2403}
2404
2405static struct pneigh_entry *pneigh_get_idx(struct seq_file *seq, loff_t *pos)
2406{
2407 struct pneigh_entry *pn = pneigh_get_first(seq);
2408
2409 if (pn) {
2410 --(*pos);
2411 while (*pos) {
2412 pn = pneigh_get_next(seq, pn, pos);
2413 if (!pn)
2414 break;
2415 }
2416 }
2417 return *pos ? NULL : pn;
2418}
2419
2420static void *neigh_get_idx_any(struct seq_file *seq, loff_t *pos)
2421{
2422 struct neigh_seq_state *state = seq->private;
2423 void *rc;
2424 loff_t idxpos = *pos;
2425
2426 rc = neigh_get_idx(seq, &idxpos);
2427 if (!rc && !(state->flags & NEIGH_SEQ_NEIGH_ONLY))
2428 rc = pneigh_get_idx(seq, &idxpos);
2429
2430 return rc;
2431}
2432
2433void *neigh_seq_start(struct seq_file *seq, loff_t *pos, struct neigh_table *tbl, unsigned int neigh_seq_flags)
2434 __acquires(rcu_bh)
2435{
2436 struct neigh_seq_state *state = seq->private;
2437
2438 state->tbl = tbl;
2439 state->bucket = 0;
2440 state->flags = (neigh_seq_flags & ~NEIGH_SEQ_IS_PNEIGH);
2441
2442 rcu_read_lock_bh();
2443 state->nht = rcu_dereference_bh(tbl->nht);
2444
2445 return *pos ? neigh_get_idx_any(seq, pos) : SEQ_START_TOKEN;
2446}
2447EXPORT_SYMBOL(neigh_seq_start);
2448
2449void *neigh_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2450{
2451 struct neigh_seq_state *state;
2452 void *rc;
2453
2454 if (v == SEQ_START_TOKEN) {
2455 rc = neigh_get_first(seq);
2456 goto out;
2457 }
2458
2459 state = seq->private;
2460 if (!(state->flags & NEIGH_SEQ_IS_PNEIGH)) {
2461 rc = neigh_get_next(seq, v, NULL);
2462 if (rc)
2463 goto out;
2464 if (!(state->flags & NEIGH_SEQ_NEIGH_ONLY))
2465 rc = pneigh_get_first(seq);
2466 } else {
2467 BUG_ON(state->flags & NEIGH_SEQ_NEIGH_ONLY);
2468 rc = pneigh_get_next(seq, v, NULL);
2469 }
2470out:
2471 ++(*pos);
2472 return rc;
2473}
2474EXPORT_SYMBOL(neigh_seq_next);
2475
2476void neigh_seq_stop(struct seq_file *seq, void *v)
2477 __releases(rcu_bh)
2478{
2479 rcu_read_unlock_bh();
2480}
2481EXPORT_SYMBOL(neigh_seq_stop);
2482
2483/* statistics via seq_file */
2484
2485static void *neigh_stat_seq_start(struct seq_file *seq, loff_t *pos)
2486{
2487 struct neigh_table *tbl = seq->private;
2488 int cpu;
2489
2490 if (*pos == 0)
2491 return SEQ_START_TOKEN;
2492
2493 for (cpu = *pos-1; cpu < nr_cpu_ids; ++cpu) {
2494 if (!cpu_possible(cpu))
2495 continue;
2496 *pos = cpu+1;
2497 return per_cpu_ptr(tbl->stats, cpu);
2498 }
2499 return NULL;
2500}
2501
2502static void *neigh_stat_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2503{
2504 struct neigh_table *tbl = seq->private;
2505 int cpu;
2506
2507 for (cpu = *pos; cpu < nr_cpu_ids; ++cpu) {
2508 if (!cpu_possible(cpu))
2509 continue;
2510 *pos = cpu+1;
2511 return per_cpu_ptr(tbl->stats, cpu);
2512 }
2513 return NULL;
2514}
2515
2516static void neigh_stat_seq_stop(struct seq_file *seq, void *v)
2517{
2518
2519}
2520
2521static int neigh_stat_seq_show(struct seq_file *seq, void *v)
2522{
2523 struct neigh_table *tbl = seq->private;
2524 struct neigh_statistics *st = v;
2525
2526 if (v == SEQ_START_TOKEN) {
2527 seq_printf(seq, "entries allocs destroys hash_grows lookups hits res_failed rcv_probes_mcast rcv_probes_ucast periodic_gc_runs forced_gc_runs unresolved_discards\n");
2528 return 0;
2529 }
2530
2531 seq_printf(seq, "%08x %08lx %08lx %08lx %08lx %08lx %08lx "
2532 "%08lx %08lx %08lx %08lx %08lx\n",
2533 atomic_read(&tbl->entries),
2534
2535 st->allocs,
2536 st->destroys,
2537 st->hash_grows,
2538
2539 st->lookups,
2540 st->hits,
2541
2542 st->res_failed,
2543
2544 st->rcv_probes_mcast,
2545 st->rcv_probes_ucast,
2546
2547 st->periodic_gc_runs,
2548 st->forced_gc_runs,
2549 st->unres_discards
2550 );
2551
2552 return 0;
2553}
2554
2555static const struct seq_operations neigh_stat_seq_ops = {
2556 .start = neigh_stat_seq_start,
2557 .next = neigh_stat_seq_next,
2558 .stop = neigh_stat_seq_stop,
2559 .show = neigh_stat_seq_show,
2560};
2561
2562static int neigh_stat_seq_open(struct inode *inode, struct file *file)
2563{
2564 int ret = seq_open(file, &neigh_stat_seq_ops);
2565
2566 if (!ret) {
2567 struct seq_file *sf = file->private_data;
2568 sf->private = PDE(inode)->data;
2569 }
2570 return ret;
2571};
2572
2573static const struct file_operations neigh_stat_seq_fops = {
2574 .owner = THIS_MODULE,
2575 .open = neigh_stat_seq_open,
2576 .read = seq_read,
2577 .llseek = seq_lseek,
2578 .release = seq_release,
2579};
2580
2581#endif /* CONFIG_PROC_FS */
2582
2583static inline size_t neigh_nlmsg_size(void)
2584{
2585 return NLMSG_ALIGN(sizeof(struct ndmsg))
2586 + nla_total_size(MAX_ADDR_LEN) /* NDA_DST */
2587 + nla_total_size(MAX_ADDR_LEN) /* NDA_LLADDR */
2588 + nla_total_size(sizeof(struct nda_cacheinfo))
2589 + nla_total_size(4); /* NDA_PROBES */
2590}
2591
2592static void __neigh_notify(struct neighbour *n, int type, int flags)
2593{
2594 struct net *net = dev_net(n->dev);
2595 struct sk_buff *skb;
2596 int err = -ENOBUFS;
2597
2598 skb = nlmsg_new(neigh_nlmsg_size(), GFP_ATOMIC);
2599 if (skb == NULL)
2600 goto errout;
2601
2602 err = neigh_fill_info(skb, n, 0, 0, type, flags);
2603 if (err < 0) {
2604 /* -EMSGSIZE implies BUG in neigh_nlmsg_size() */
2605 WARN_ON(err == -EMSGSIZE);
2606 kfree_skb(skb);
2607 goto errout;
2608 }
2609 rtnl_notify(skb, net, 0, RTNLGRP_NEIGH, NULL, GFP_ATOMIC);
2610 return;
2611errout:
2612 if (err < 0)
2613 rtnl_set_sk_err(net, RTNLGRP_NEIGH, err);
2614}
2615
2616#ifdef CONFIG_ARPD
2617void neigh_app_ns(struct neighbour *n)
2618{
2619 __neigh_notify(n, RTM_GETNEIGH, NLM_F_REQUEST);
2620}
2621EXPORT_SYMBOL(neigh_app_ns);
2622#endif /* CONFIG_ARPD */
2623
2624#ifdef CONFIG_SYSCTL
2625
2626#define NEIGH_VARS_MAX 19
2627
2628static struct neigh_sysctl_table {
2629 struct ctl_table_header *sysctl_header;
2630 struct ctl_table neigh_vars[NEIGH_VARS_MAX];
2631 char *dev_name;
2632} neigh_sysctl_template __read_mostly = {
2633 .neigh_vars = {
2634 {
2635 .procname = "mcast_solicit",
2636 .maxlen = sizeof(int),
2637 .mode = 0644,
2638 .proc_handler = proc_dointvec,
2639 },
2640 {
2641 .procname = "ucast_solicit",
2642 .maxlen = sizeof(int),
2643 .mode = 0644,
2644 .proc_handler = proc_dointvec,
2645 },
2646 {
2647 .procname = "app_solicit",
2648 .maxlen = sizeof(int),
2649 .mode = 0644,
2650 .proc_handler = proc_dointvec,
2651 },
2652 {
2653 .procname = "retrans_time",
2654 .maxlen = sizeof(int),
2655 .mode = 0644,
2656 .proc_handler = proc_dointvec_userhz_jiffies,
2657 },
2658 {
2659 .procname = "base_reachable_time",
2660 .maxlen = sizeof(int),
2661 .mode = 0644,
2662 .proc_handler = proc_dointvec_jiffies,
2663 },
2664 {
2665 .procname = "delay_first_probe_time",
2666 .maxlen = sizeof(int),
2667 .mode = 0644,
2668 .proc_handler = proc_dointvec_jiffies,
2669 },
2670 {
2671 .procname = "gc_stale_time",
2672 .maxlen = sizeof(int),
2673 .mode = 0644,
2674 .proc_handler = proc_dointvec_jiffies,
2675 },
2676 {
2677 .procname = "unres_qlen",
2678 .maxlen = sizeof(int),
2679 .mode = 0644,
2680 .proc_handler = proc_dointvec,
2681 },
2682 {
2683 .procname = "proxy_qlen",
2684 .maxlen = sizeof(int),
2685 .mode = 0644,
2686 .proc_handler = proc_dointvec,
2687 },
2688 {
2689 .procname = "anycast_delay",
2690 .maxlen = sizeof(int),
2691 .mode = 0644,
2692 .proc_handler = proc_dointvec_userhz_jiffies,
2693 },
2694 {
2695 .procname = "proxy_delay",
2696 .maxlen = sizeof(int),
2697 .mode = 0644,
2698 .proc_handler = proc_dointvec_userhz_jiffies,
2699 },
2700 {
2701 .procname = "locktime",
2702 .maxlen = sizeof(int),
2703 .mode = 0644,
2704 .proc_handler = proc_dointvec_userhz_jiffies,
2705 },
2706 {
2707 .procname = "retrans_time_ms",
2708 .maxlen = sizeof(int),
2709 .mode = 0644,
2710 .proc_handler = proc_dointvec_ms_jiffies,
2711 },
2712 {
2713 .procname = "base_reachable_time_ms",
2714 .maxlen = sizeof(int),
2715 .mode = 0644,
2716 .proc_handler = proc_dointvec_ms_jiffies,
2717 },
2718 {
2719 .procname = "gc_interval",
2720 .maxlen = sizeof(int),
2721 .mode = 0644,
2722 .proc_handler = proc_dointvec_jiffies,
2723 },
2724 {
2725 .procname = "gc_thresh1",
2726 .maxlen = sizeof(int),
2727 .mode = 0644,
2728 .proc_handler = proc_dointvec,
2729 },
2730 {
2731 .procname = "gc_thresh2",
2732 .maxlen = sizeof(int),
2733 .mode = 0644,
2734 .proc_handler = proc_dointvec,
2735 },
2736 {
2737 .procname = "gc_thresh3",
2738 .maxlen = sizeof(int),
2739 .mode = 0644,
2740 .proc_handler = proc_dointvec,
2741 },
2742 {},
2743 },
2744};
2745
2746int neigh_sysctl_register(struct net_device *dev, struct neigh_parms *p,
2747 char *p_name, proc_handler *handler)
2748{
2749 struct neigh_sysctl_table *t;
2750 const char *dev_name_source = NULL;
2751
2752#define NEIGH_CTL_PATH_ROOT 0
2753#define NEIGH_CTL_PATH_PROTO 1
2754#define NEIGH_CTL_PATH_NEIGH 2
2755#define NEIGH_CTL_PATH_DEV 3
2756
2757 struct ctl_path neigh_path[] = {
2758 { .procname = "net", },
2759 { .procname = "proto", },
2760 { .procname = "neigh", },
2761 { .procname = "default", },
2762 { },
2763 };
2764
2765 t = kmemdup(&neigh_sysctl_template, sizeof(*t), GFP_KERNEL);
2766 if (!t)
2767 goto err;
2768
2769 t->neigh_vars[0].data = &p->mcast_probes;
2770 t->neigh_vars[1].data = &p->ucast_probes;
2771 t->neigh_vars[2].data = &p->app_probes;
2772 t->neigh_vars[3].data = &p->retrans_time;
2773 t->neigh_vars[4].data = &p->base_reachable_time;
2774 t->neigh_vars[5].data = &p->delay_probe_time;
2775 t->neigh_vars[6].data = &p->gc_staletime;
2776 t->neigh_vars[7].data = &p->queue_len;
2777 t->neigh_vars[8].data = &p->proxy_qlen;
2778 t->neigh_vars[9].data = &p->anycast_delay;
2779 t->neigh_vars[10].data = &p->proxy_delay;
2780 t->neigh_vars[11].data = &p->locktime;
2781 t->neigh_vars[12].data = &p->retrans_time;
2782 t->neigh_vars[13].data = &p->base_reachable_time;
2783
2784 if (dev) {
2785 dev_name_source = dev->name;
2786 /* Terminate the table early */
2787 memset(&t->neigh_vars[14], 0, sizeof(t->neigh_vars[14]));
2788 } else {
2789 dev_name_source = neigh_path[NEIGH_CTL_PATH_DEV].procname;
2790 t->neigh_vars[14].data = (int *)(p + 1);
2791 t->neigh_vars[15].data = (int *)(p + 1) + 1;
2792 t->neigh_vars[16].data = (int *)(p + 1) + 2;
2793 t->neigh_vars[17].data = (int *)(p + 1) + 3;
2794 }
2795
2796
2797 if (handler) {
2798 /* RetransTime */
2799 t->neigh_vars[3].proc_handler = handler;
2800 t->neigh_vars[3].extra1 = dev;
2801 /* ReachableTime */
2802 t->neigh_vars[4].proc_handler = handler;
2803 t->neigh_vars[4].extra1 = dev;
2804 /* RetransTime (in milliseconds)*/
2805 t->neigh_vars[12].proc_handler = handler;
2806 t->neigh_vars[12].extra1 = dev;
2807 /* ReachableTime (in milliseconds) */
2808 t->neigh_vars[13].proc_handler = handler;
2809 t->neigh_vars[13].extra1 = dev;
2810 }
2811
2812 t->dev_name = kstrdup(dev_name_source, GFP_KERNEL);
2813 if (!t->dev_name)
2814 goto free;
2815
2816 neigh_path[NEIGH_CTL_PATH_DEV].procname = t->dev_name;
2817 neigh_path[NEIGH_CTL_PATH_PROTO].procname = p_name;
2818
2819 t->sysctl_header =
2820 register_net_sysctl_table(neigh_parms_net(p), neigh_path, t->neigh_vars);
2821 if (!t->sysctl_header)
2822 goto free_procname;
2823
2824 p->sysctl_table = t;
2825 return 0;
2826
2827free_procname:
2828 kfree(t->dev_name);
2829free:
2830 kfree(t);
2831err:
2832 return -ENOBUFS;
2833}
2834EXPORT_SYMBOL(neigh_sysctl_register);
2835
2836void neigh_sysctl_unregister(struct neigh_parms *p)
2837{
2838 if (p->sysctl_table) {
2839 struct neigh_sysctl_table *t = p->sysctl_table;
2840 p->sysctl_table = NULL;
2841 unregister_sysctl_table(t->sysctl_header);
2842 kfree(t->dev_name);
2843 kfree(t);
2844 }
2845}
2846EXPORT_SYMBOL(neigh_sysctl_unregister);
2847
2848#endif /* CONFIG_SYSCTL */
2849
2850static int __init neigh_init(void)
2851{
2852 rtnl_register(PF_UNSPEC, RTM_NEWNEIGH, neigh_add, NULL, NULL);
2853 rtnl_register(PF_UNSPEC, RTM_DELNEIGH, neigh_delete, NULL, NULL);
2854 rtnl_register(PF_UNSPEC, RTM_GETNEIGH, NULL, neigh_dump_info, NULL);
2855
2856 rtnl_register(PF_UNSPEC, RTM_GETNEIGHTBL, NULL, neightbl_dump_info,
2857 NULL);
2858 rtnl_register(PF_UNSPEC, RTM_SETNEIGHTBL, neightbl_set, NULL, NULL);
2859
2860 return 0;
2861}
2862
2863subsys_initcall(neigh_init);
2864
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Generic address resolution entity
4 *
5 * Authors:
6 * Pedro Roque <roque@di.fc.ul.pt>
7 * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
8 *
9 * Fixes:
10 * Vitaly E. Lavrov releasing NULL neighbor in neigh_add.
11 * Harald Welte Add neighbour cache statistics like rtstat
12 */
13
14#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
15
16#include <linux/slab.h>
17#include <linux/kmemleak.h>
18#include <linux/types.h>
19#include <linux/kernel.h>
20#include <linux/module.h>
21#include <linux/socket.h>
22#include <linux/netdevice.h>
23#include <linux/proc_fs.h>
24#ifdef CONFIG_SYSCTL
25#include <linux/sysctl.h>
26#endif
27#include <linux/times.h>
28#include <net/net_namespace.h>
29#include <net/neighbour.h>
30#include <net/arp.h>
31#include <net/dst.h>
32#include <net/sock.h>
33#include <net/netevent.h>
34#include <net/netlink.h>
35#include <linux/rtnetlink.h>
36#include <linux/random.h>
37#include <linux/string.h>
38#include <linux/log2.h>
39#include <linux/inetdevice.h>
40#include <net/addrconf.h>
41
42#include <trace/events/neigh.h>
43
44#define NEIGH_DEBUG 1
45#define neigh_dbg(level, fmt, ...) \
46do { \
47 if (level <= NEIGH_DEBUG) \
48 pr_debug(fmt, ##__VA_ARGS__); \
49} while (0)
50
51#define PNEIGH_HASHMASK 0xF
52
53static void neigh_timer_handler(struct timer_list *t);
54static void __neigh_notify(struct neighbour *n, int type, int flags,
55 u32 pid);
56static void neigh_update_notify(struct neighbour *neigh, u32 nlmsg_pid);
57static int pneigh_ifdown_and_unlock(struct neigh_table *tbl,
58 struct net_device *dev);
59
60#ifdef CONFIG_PROC_FS
61static const struct seq_operations neigh_stat_seq_ops;
62#endif
63
64/*
65 Neighbour hash table buckets are protected with rwlock tbl->lock.
66
67 - All the scans/updates to hash buckets MUST be made under this lock.
68 - NOTHING clever should be made under this lock: no callbacks
69 to protocol backends, no attempts to send something to network.
70 It will result in deadlocks, if backend/driver wants to use neighbour
71 cache.
72 - If the entry requires some non-trivial actions, increase
73 its reference count and release table lock.
74
75 Neighbour entries are protected:
76 - with reference count.
77 - with rwlock neigh->lock
78
79 Reference count prevents destruction.
80
81 neigh->lock mainly serializes ll address data and its validity state.
82 However, the same lock is used to protect another entry fields:
83 - timer
84 - resolution queue
85
86 Again, nothing clever shall be made under neigh->lock,
87 the most complicated procedure, which we allow is dev->hard_header.
88 It is supposed, that dev->hard_header is simplistic and does
89 not make callbacks to neighbour tables.
90 */
91
92static int neigh_blackhole(struct neighbour *neigh, struct sk_buff *skb)
93{
94 kfree_skb(skb);
95 return -ENETDOWN;
96}
97
98static void neigh_cleanup_and_release(struct neighbour *neigh)
99{
100 trace_neigh_cleanup_and_release(neigh, 0);
101 __neigh_notify(neigh, RTM_DELNEIGH, 0, 0);
102 call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, neigh);
103 neigh_release(neigh);
104}
105
106/*
107 * It is random distribution in the interval (1/2)*base...(3/2)*base.
108 * It corresponds to default IPv6 settings and is not overridable,
109 * because it is really reasonable choice.
110 */
111
112unsigned long neigh_rand_reach_time(unsigned long base)
113{
114 return base ? get_random_u32_below(base) + (base >> 1) : 0;
115}
116EXPORT_SYMBOL(neigh_rand_reach_time);
117
118static void neigh_mark_dead(struct neighbour *n)
119{
120 n->dead = 1;
121 if (!list_empty(&n->gc_list)) {
122 list_del_init(&n->gc_list);
123 atomic_dec(&n->tbl->gc_entries);
124 }
125 if (!list_empty(&n->managed_list))
126 list_del_init(&n->managed_list);
127}
128
129static void neigh_update_gc_list(struct neighbour *n)
130{
131 bool on_gc_list, exempt_from_gc;
132
133 write_lock_bh(&n->tbl->lock);
134 write_lock(&n->lock);
135 if (n->dead)
136 goto out;
137
138 /* remove from the gc list if new state is permanent or if neighbor
139 * is externally learned; otherwise entry should be on the gc list
140 */
141 exempt_from_gc = n->nud_state & NUD_PERMANENT ||
142 n->flags & NTF_EXT_LEARNED;
143 on_gc_list = !list_empty(&n->gc_list);
144
145 if (exempt_from_gc && on_gc_list) {
146 list_del_init(&n->gc_list);
147 atomic_dec(&n->tbl->gc_entries);
148 } else if (!exempt_from_gc && !on_gc_list) {
149 /* add entries to the tail; cleaning removes from the front */
150 list_add_tail(&n->gc_list, &n->tbl->gc_list);
151 atomic_inc(&n->tbl->gc_entries);
152 }
153out:
154 write_unlock(&n->lock);
155 write_unlock_bh(&n->tbl->lock);
156}
157
158static void neigh_update_managed_list(struct neighbour *n)
159{
160 bool on_managed_list, add_to_managed;
161
162 write_lock_bh(&n->tbl->lock);
163 write_lock(&n->lock);
164 if (n->dead)
165 goto out;
166
167 add_to_managed = n->flags & NTF_MANAGED;
168 on_managed_list = !list_empty(&n->managed_list);
169
170 if (!add_to_managed && on_managed_list)
171 list_del_init(&n->managed_list);
172 else if (add_to_managed && !on_managed_list)
173 list_add_tail(&n->managed_list, &n->tbl->managed_list);
174out:
175 write_unlock(&n->lock);
176 write_unlock_bh(&n->tbl->lock);
177}
178
179static void neigh_update_flags(struct neighbour *neigh, u32 flags, int *notify,
180 bool *gc_update, bool *managed_update)
181{
182 u32 ndm_flags, old_flags = neigh->flags;
183
184 if (!(flags & NEIGH_UPDATE_F_ADMIN))
185 return;
186
187 ndm_flags = (flags & NEIGH_UPDATE_F_EXT_LEARNED) ? NTF_EXT_LEARNED : 0;
188 ndm_flags |= (flags & NEIGH_UPDATE_F_MANAGED) ? NTF_MANAGED : 0;
189
190 if ((old_flags ^ ndm_flags) & NTF_EXT_LEARNED) {
191 if (ndm_flags & NTF_EXT_LEARNED)
192 neigh->flags |= NTF_EXT_LEARNED;
193 else
194 neigh->flags &= ~NTF_EXT_LEARNED;
195 *notify = 1;
196 *gc_update = true;
197 }
198 if ((old_flags ^ ndm_flags) & NTF_MANAGED) {
199 if (ndm_flags & NTF_MANAGED)
200 neigh->flags |= NTF_MANAGED;
201 else
202 neigh->flags &= ~NTF_MANAGED;
203 *notify = 1;
204 *managed_update = true;
205 }
206}
207
208static bool neigh_del(struct neighbour *n, struct neighbour __rcu **np,
209 struct neigh_table *tbl)
210{
211 bool retval = false;
212
213 write_lock(&n->lock);
214 if (refcount_read(&n->refcnt) == 1) {
215 struct neighbour *neigh;
216
217 neigh = rcu_dereference_protected(n->next,
218 lockdep_is_held(&tbl->lock));
219 rcu_assign_pointer(*np, neigh);
220 neigh_mark_dead(n);
221 retval = true;
222 }
223 write_unlock(&n->lock);
224 if (retval)
225 neigh_cleanup_and_release(n);
226 return retval;
227}
228
229bool neigh_remove_one(struct neighbour *ndel, struct neigh_table *tbl)
230{
231 struct neigh_hash_table *nht;
232 void *pkey = ndel->primary_key;
233 u32 hash_val;
234 struct neighbour *n;
235 struct neighbour __rcu **np;
236
237 nht = rcu_dereference_protected(tbl->nht,
238 lockdep_is_held(&tbl->lock));
239 hash_val = tbl->hash(pkey, ndel->dev, nht->hash_rnd);
240 hash_val = hash_val >> (32 - nht->hash_shift);
241
242 np = &nht->hash_buckets[hash_val];
243 while ((n = rcu_dereference_protected(*np,
244 lockdep_is_held(&tbl->lock)))) {
245 if (n == ndel)
246 return neigh_del(n, np, tbl);
247 np = &n->next;
248 }
249 return false;
250}
251
252static int neigh_forced_gc(struct neigh_table *tbl)
253{
254 int max_clean = atomic_read(&tbl->gc_entries) -
255 READ_ONCE(tbl->gc_thresh2);
256 u64 tmax = ktime_get_ns() + NSEC_PER_MSEC;
257 unsigned long tref = jiffies - 5 * HZ;
258 struct neighbour *n, *tmp;
259 int shrunk = 0;
260 int loop = 0;
261
262 NEIGH_CACHE_STAT_INC(tbl, forced_gc_runs);
263
264 write_lock_bh(&tbl->lock);
265
266 list_for_each_entry_safe(n, tmp, &tbl->gc_list, gc_list) {
267 if (refcount_read(&n->refcnt) == 1) {
268 bool remove = false;
269
270 write_lock(&n->lock);
271 if ((n->nud_state == NUD_FAILED) ||
272 (n->nud_state == NUD_NOARP) ||
273 (tbl->is_multicast &&
274 tbl->is_multicast(n->primary_key)) ||
275 !time_in_range(n->updated, tref, jiffies))
276 remove = true;
277 write_unlock(&n->lock);
278
279 if (remove && neigh_remove_one(n, tbl))
280 shrunk++;
281 if (shrunk >= max_clean)
282 break;
283 if (++loop == 16) {
284 if (ktime_get_ns() > tmax)
285 goto unlock;
286 loop = 0;
287 }
288 }
289 }
290
291 WRITE_ONCE(tbl->last_flush, jiffies);
292unlock:
293 write_unlock_bh(&tbl->lock);
294
295 return shrunk;
296}
297
298static void neigh_add_timer(struct neighbour *n, unsigned long when)
299{
300 /* Use safe distance from the jiffies - LONG_MAX point while timer
301 * is running in DELAY/PROBE state but still show to user space
302 * large times in the past.
303 */
304 unsigned long mint = jiffies - (LONG_MAX - 86400 * HZ);
305
306 neigh_hold(n);
307 if (!time_in_range(n->confirmed, mint, jiffies))
308 n->confirmed = mint;
309 if (time_before(n->used, n->confirmed))
310 n->used = n->confirmed;
311 if (unlikely(mod_timer(&n->timer, when))) {
312 printk("NEIGH: BUG, double timer add, state is %x\n",
313 n->nud_state);
314 dump_stack();
315 }
316}
317
318static int neigh_del_timer(struct neighbour *n)
319{
320 if ((n->nud_state & NUD_IN_TIMER) &&
321 del_timer(&n->timer)) {
322 neigh_release(n);
323 return 1;
324 }
325 return 0;
326}
327
328static struct neigh_parms *neigh_get_dev_parms_rcu(struct net_device *dev,
329 int family)
330{
331 switch (family) {
332 case AF_INET:
333 return __in_dev_arp_parms_get_rcu(dev);
334 case AF_INET6:
335 return __in6_dev_nd_parms_get_rcu(dev);
336 }
337 return NULL;
338}
339
340static void neigh_parms_qlen_dec(struct net_device *dev, int family)
341{
342 struct neigh_parms *p;
343
344 rcu_read_lock();
345 p = neigh_get_dev_parms_rcu(dev, family);
346 if (p)
347 p->qlen--;
348 rcu_read_unlock();
349}
350
351static void pneigh_queue_purge(struct sk_buff_head *list, struct net *net,
352 int family)
353{
354 struct sk_buff_head tmp;
355 unsigned long flags;
356 struct sk_buff *skb;
357
358 skb_queue_head_init(&tmp);
359 spin_lock_irqsave(&list->lock, flags);
360 skb = skb_peek(list);
361 while (skb != NULL) {
362 struct sk_buff *skb_next = skb_peek_next(skb, list);
363 struct net_device *dev = skb->dev;
364
365 if (net == NULL || net_eq(dev_net(dev), net)) {
366 neigh_parms_qlen_dec(dev, family);
367 __skb_unlink(skb, list);
368 __skb_queue_tail(&tmp, skb);
369 }
370 skb = skb_next;
371 }
372 spin_unlock_irqrestore(&list->lock, flags);
373
374 while ((skb = __skb_dequeue(&tmp))) {
375 dev_put(skb->dev);
376 kfree_skb(skb);
377 }
378}
379
380static void neigh_flush_dev(struct neigh_table *tbl, struct net_device *dev,
381 bool skip_perm)
382{
383 int i;
384 struct neigh_hash_table *nht;
385
386 nht = rcu_dereference_protected(tbl->nht,
387 lockdep_is_held(&tbl->lock));
388
389 for (i = 0; i < (1 << nht->hash_shift); i++) {
390 struct neighbour *n;
391 struct neighbour __rcu **np = &nht->hash_buckets[i];
392
393 while ((n = rcu_dereference_protected(*np,
394 lockdep_is_held(&tbl->lock))) != NULL) {
395 if (dev && n->dev != dev) {
396 np = &n->next;
397 continue;
398 }
399 if (skip_perm && n->nud_state & NUD_PERMANENT) {
400 np = &n->next;
401 continue;
402 }
403 rcu_assign_pointer(*np,
404 rcu_dereference_protected(n->next,
405 lockdep_is_held(&tbl->lock)));
406 write_lock(&n->lock);
407 neigh_del_timer(n);
408 neigh_mark_dead(n);
409 if (refcount_read(&n->refcnt) != 1) {
410 /* The most unpleasant situation.
411 We must destroy neighbour entry,
412 but someone still uses it.
413
414 The destroy will be delayed until
415 the last user releases us, but
416 we must kill timers etc. and move
417 it to safe state.
418 */
419 __skb_queue_purge(&n->arp_queue);
420 n->arp_queue_len_bytes = 0;
421 WRITE_ONCE(n->output, neigh_blackhole);
422 if (n->nud_state & NUD_VALID)
423 n->nud_state = NUD_NOARP;
424 else
425 n->nud_state = NUD_NONE;
426 neigh_dbg(2, "neigh %p is stray\n", n);
427 }
428 write_unlock(&n->lock);
429 neigh_cleanup_and_release(n);
430 }
431 }
432}
433
434void neigh_changeaddr(struct neigh_table *tbl, struct net_device *dev)
435{
436 write_lock_bh(&tbl->lock);
437 neigh_flush_dev(tbl, dev, false);
438 write_unlock_bh(&tbl->lock);
439}
440EXPORT_SYMBOL(neigh_changeaddr);
441
442static int __neigh_ifdown(struct neigh_table *tbl, struct net_device *dev,
443 bool skip_perm)
444{
445 write_lock_bh(&tbl->lock);
446 neigh_flush_dev(tbl, dev, skip_perm);
447 pneigh_ifdown_and_unlock(tbl, dev);
448 pneigh_queue_purge(&tbl->proxy_queue, dev ? dev_net(dev) : NULL,
449 tbl->family);
450 if (skb_queue_empty_lockless(&tbl->proxy_queue))
451 del_timer_sync(&tbl->proxy_timer);
452 return 0;
453}
454
455int neigh_carrier_down(struct neigh_table *tbl, struct net_device *dev)
456{
457 __neigh_ifdown(tbl, dev, true);
458 return 0;
459}
460EXPORT_SYMBOL(neigh_carrier_down);
461
462int neigh_ifdown(struct neigh_table *tbl, struct net_device *dev)
463{
464 __neigh_ifdown(tbl, dev, false);
465 return 0;
466}
467EXPORT_SYMBOL(neigh_ifdown);
468
469static struct neighbour *neigh_alloc(struct neigh_table *tbl,
470 struct net_device *dev,
471 u32 flags, bool exempt_from_gc)
472{
473 struct neighbour *n = NULL;
474 unsigned long now = jiffies;
475 int entries, gc_thresh3;
476
477 if (exempt_from_gc)
478 goto do_alloc;
479
480 entries = atomic_inc_return(&tbl->gc_entries) - 1;
481 gc_thresh3 = READ_ONCE(tbl->gc_thresh3);
482 if (entries >= gc_thresh3 ||
483 (entries >= READ_ONCE(tbl->gc_thresh2) &&
484 time_after(now, READ_ONCE(tbl->last_flush) + 5 * HZ))) {
485 if (!neigh_forced_gc(tbl) && entries >= gc_thresh3) {
486 net_info_ratelimited("%s: neighbor table overflow!\n",
487 tbl->id);
488 NEIGH_CACHE_STAT_INC(tbl, table_fulls);
489 goto out_entries;
490 }
491 }
492
493do_alloc:
494 n = kzalloc(tbl->entry_size + dev->neigh_priv_len, GFP_ATOMIC);
495 if (!n)
496 goto out_entries;
497
498 __skb_queue_head_init(&n->arp_queue);
499 rwlock_init(&n->lock);
500 seqlock_init(&n->ha_lock);
501 n->updated = n->used = now;
502 n->nud_state = NUD_NONE;
503 n->output = neigh_blackhole;
504 n->flags = flags;
505 seqlock_init(&n->hh.hh_lock);
506 n->parms = neigh_parms_clone(&tbl->parms);
507 timer_setup(&n->timer, neigh_timer_handler, 0);
508
509 NEIGH_CACHE_STAT_INC(tbl, allocs);
510 n->tbl = tbl;
511 refcount_set(&n->refcnt, 1);
512 n->dead = 1;
513 INIT_LIST_HEAD(&n->gc_list);
514 INIT_LIST_HEAD(&n->managed_list);
515
516 atomic_inc(&tbl->entries);
517out:
518 return n;
519
520out_entries:
521 if (!exempt_from_gc)
522 atomic_dec(&tbl->gc_entries);
523 goto out;
524}
525
526static void neigh_get_hash_rnd(u32 *x)
527{
528 *x = get_random_u32() | 1;
529}
530
531static struct neigh_hash_table *neigh_hash_alloc(unsigned int shift)
532{
533 size_t size = (1 << shift) * sizeof(struct neighbour *);
534 struct neigh_hash_table *ret;
535 struct neighbour __rcu **buckets;
536 int i;
537
538 ret = kmalloc(sizeof(*ret), GFP_ATOMIC);
539 if (!ret)
540 return NULL;
541 if (size <= PAGE_SIZE) {
542 buckets = kzalloc(size, GFP_ATOMIC);
543 } else {
544 buckets = (struct neighbour __rcu **)
545 __get_free_pages(GFP_ATOMIC | __GFP_ZERO,
546 get_order(size));
547 kmemleak_alloc(buckets, size, 1, GFP_ATOMIC);
548 }
549 if (!buckets) {
550 kfree(ret);
551 return NULL;
552 }
553 ret->hash_buckets = buckets;
554 ret->hash_shift = shift;
555 for (i = 0; i < NEIGH_NUM_HASH_RND; i++)
556 neigh_get_hash_rnd(&ret->hash_rnd[i]);
557 return ret;
558}
559
560static void neigh_hash_free_rcu(struct rcu_head *head)
561{
562 struct neigh_hash_table *nht = container_of(head,
563 struct neigh_hash_table,
564 rcu);
565 size_t size = (1 << nht->hash_shift) * sizeof(struct neighbour *);
566 struct neighbour __rcu **buckets = nht->hash_buckets;
567
568 if (size <= PAGE_SIZE) {
569 kfree(buckets);
570 } else {
571 kmemleak_free(buckets);
572 free_pages((unsigned long)buckets, get_order(size));
573 }
574 kfree(nht);
575}
576
577static struct neigh_hash_table *neigh_hash_grow(struct neigh_table *tbl,
578 unsigned long new_shift)
579{
580 unsigned int i, hash;
581 struct neigh_hash_table *new_nht, *old_nht;
582
583 NEIGH_CACHE_STAT_INC(tbl, hash_grows);
584
585 old_nht = rcu_dereference_protected(tbl->nht,
586 lockdep_is_held(&tbl->lock));
587 new_nht = neigh_hash_alloc(new_shift);
588 if (!new_nht)
589 return old_nht;
590
591 for (i = 0; i < (1 << old_nht->hash_shift); i++) {
592 struct neighbour *n, *next;
593
594 for (n = rcu_dereference_protected(old_nht->hash_buckets[i],
595 lockdep_is_held(&tbl->lock));
596 n != NULL;
597 n = next) {
598 hash = tbl->hash(n->primary_key, n->dev,
599 new_nht->hash_rnd);
600
601 hash >>= (32 - new_nht->hash_shift);
602 next = rcu_dereference_protected(n->next,
603 lockdep_is_held(&tbl->lock));
604
605 rcu_assign_pointer(n->next,
606 rcu_dereference_protected(
607 new_nht->hash_buckets[hash],
608 lockdep_is_held(&tbl->lock)));
609 rcu_assign_pointer(new_nht->hash_buckets[hash], n);
610 }
611 }
612
613 rcu_assign_pointer(tbl->nht, new_nht);
614 call_rcu(&old_nht->rcu, neigh_hash_free_rcu);
615 return new_nht;
616}
617
618struct neighbour *neigh_lookup(struct neigh_table *tbl, const void *pkey,
619 struct net_device *dev)
620{
621 struct neighbour *n;
622
623 NEIGH_CACHE_STAT_INC(tbl, lookups);
624
625 rcu_read_lock();
626 n = __neigh_lookup_noref(tbl, pkey, dev);
627 if (n) {
628 if (!refcount_inc_not_zero(&n->refcnt))
629 n = NULL;
630 NEIGH_CACHE_STAT_INC(tbl, hits);
631 }
632
633 rcu_read_unlock();
634 return n;
635}
636EXPORT_SYMBOL(neigh_lookup);
637
638static struct neighbour *
639___neigh_create(struct neigh_table *tbl, const void *pkey,
640 struct net_device *dev, u32 flags,
641 bool exempt_from_gc, bool want_ref)
642{
643 u32 hash_val, key_len = tbl->key_len;
644 struct neighbour *n1, *rc, *n;
645 struct neigh_hash_table *nht;
646 int error;
647
648 n = neigh_alloc(tbl, dev, flags, exempt_from_gc);
649 trace_neigh_create(tbl, dev, pkey, n, exempt_from_gc);
650 if (!n) {
651 rc = ERR_PTR(-ENOBUFS);
652 goto out;
653 }
654
655 memcpy(n->primary_key, pkey, key_len);
656 n->dev = dev;
657 netdev_hold(dev, &n->dev_tracker, GFP_ATOMIC);
658
659 /* Protocol specific setup. */
660 if (tbl->constructor && (error = tbl->constructor(n)) < 0) {
661 rc = ERR_PTR(error);
662 goto out_neigh_release;
663 }
664
665 if (dev->netdev_ops->ndo_neigh_construct) {
666 error = dev->netdev_ops->ndo_neigh_construct(dev, n);
667 if (error < 0) {
668 rc = ERR_PTR(error);
669 goto out_neigh_release;
670 }
671 }
672
673 /* Device specific setup. */
674 if (n->parms->neigh_setup &&
675 (error = n->parms->neigh_setup(n)) < 0) {
676 rc = ERR_PTR(error);
677 goto out_neigh_release;
678 }
679
680 n->confirmed = jiffies - (NEIGH_VAR(n->parms, BASE_REACHABLE_TIME) << 1);
681
682 write_lock_bh(&tbl->lock);
683 nht = rcu_dereference_protected(tbl->nht,
684 lockdep_is_held(&tbl->lock));
685
686 if (atomic_read(&tbl->entries) > (1 << nht->hash_shift))
687 nht = neigh_hash_grow(tbl, nht->hash_shift + 1);
688
689 hash_val = tbl->hash(n->primary_key, dev, nht->hash_rnd) >> (32 - nht->hash_shift);
690
691 if (n->parms->dead) {
692 rc = ERR_PTR(-EINVAL);
693 goto out_tbl_unlock;
694 }
695
696 for (n1 = rcu_dereference_protected(nht->hash_buckets[hash_val],
697 lockdep_is_held(&tbl->lock));
698 n1 != NULL;
699 n1 = rcu_dereference_protected(n1->next,
700 lockdep_is_held(&tbl->lock))) {
701 if (dev == n1->dev && !memcmp(n1->primary_key, n->primary_key, key_len)) {
702 if (want_ref)
703 neigh_hold(n1);
704 rc = n1;
705 goto out_tbl_unlock;
706 }
707 }
708
709 n->dead = 0;
710 if (!exempt_from_gc)
711 list_add_tail(&n->gc_list, &n->tbl->gc_list);
712 if (n->flags & NTF_MANAGED)
713 list_add_tail(&n->managed_list, &n->tbl->managed_list);
714 if (want_ref)
715 neigh_hold(n);
716 rcu_assign_pointer(n->next,
717 rcu_dereference_protected(nht->hash_buckets[hash_val],
718 lockdep_is_held(&tbl->lock)));
719 rcu_assign_pointer(nht->hash_buckets[hash_val], n);
720 write_unlock_bh(&tbl->lock);
721 neigh_dbg(2, "neigh %p is created\n", n);
722 rc = n;
723out:
724 return rc;
725out_tbl_unlock:
726 write_unlock_bh(&tbl->lock);
727out_neigh_release:
728 if (!exempt_from_gc)
729 atomic_dec(&tbl->gc_entries);
730 neigh_release(n);
731 goto out;
732}
733
734struct neighbour *__neigh_create(struct neigh_table *tbl, const void *pkey,
735 struct net_device *dev, bool want_ref)
736{
737 return ___neigh_create(tbl, pkey, dev, 0, false, want_ref);
738}
739EXPORT_SYMBOL(__neigh_create);
740
741static u32 pneigh_hash(const void *pkey, unsigned int key_len)
742{
743 u32 hash_val = *(u32 *)(pkey + key_len - 4);
744 hash_val ^= (hash_val >> 16);
745 hash_val ^= hash_val >> 8;
746 hash_val ^= hash_val >> 4;
747 hash_val &= PNEIGH_HASHMASK;
748 return hash_val;
749}
750
751static struct pneigh_entry *__pneigh_lookup_1(struct pneigh_entry *n,
752 struct net *net,
753 const void *pkey,
754 unsigned int key_len,
755 struct net_device *dev)
756{
757 while (n) {
758 if (!memcmp(n->key, pkey, key_len) &&
759 net_eq(pneigh_net(n), net) &&
760 (n->dev == dev || !n->dev))
761 return n;
762 n = n->next;
763 }
764 return NULL;
765}
766
767struct pneigh_entry *__pneigh_lookup(struct neigh_table *tbl,
768 struct net *net, const void *pkey, struct net_device *dev)
769{
770 unsigned int key_len = tbl->key_len;
771 u32 hash_val = pneigh_hash(pkey, key_len);
772
773 return __pneigh_lookup_1(tbl->phash_buckets[hash_val],
774 net, pkey, key_len, dev);
775}
776EXPORT_SYMBOL_GPL(__pneigh_lookup);
777
778struct pneigh_entry * pneigh_lookup(struct neigh_table *tbl,
779 struct net *net, const void *pkey,
780 struct net_device *dev, int creat)
781{
782 struct pneigh_entry *n;
783 unsigned int key_len = tbl->key_len;
784 u32 hash_val = pneigh_hash(pkey, key_len);
785
786 read_lock_bh(&tbl->lock);
787 n = __pneigh_lookup_1(tbl->phash_buckets[hash_val],
788 net, pkey, key_len, dev);
789 read_unlock_bh(&tbl->lock);
790
791 if (n || !creat)
792 goto out;
793
794 ASSERT_RTNL();
795
796 n = kzalloc(sizeof(*n) + key_len, GFP_KERNEL);
797 if (!n)
798 goto out;
799
800 write_pnet(&n->net, net);
801 memcpy(n->key, pkey, key_len);
802 n->dev = dev;
803 netdev_hold(dev, &n->dev_tracker, GFP_KERNEL);
804
805 if (tbl->pconstructor && tbl->pconstructor(n)) {
806 netdev_put(dev, &n->dev_tracker);
807 kfree(n);
808 n = NULL;
809 goto out;
810 }
811
812 write_lock_bh(&tbl->lock);
813 n->next = tbl->phash_buckets[hash_val];
814 tbl->phash_buckets[hash_val] = n;
815 write_unlock_bh(&tbl->lock);
816out:
817 return n;
818}
819EXPORT_SYMBOL(pneigh_lookup);
820
821
822int pneigh_delete(struct neigh_table *tbl, struct net *net, const void *pkey,
823 struct net_device *dev)
824{
825 struct pneigh_entry *n, **np;
826 unsigned int key_len = tbl->key_len;
827 u32 hash_val = pneigh_hash(pkey, key_len);
828
829 write_lock_bh(&tbl->lock);
830 for (np = &tbl->phash_buckets[hash_val]; (n = *np) != NULL;
831 np = &n->next) {
832 if (!memcmp(n->key, pkey, key_len) && n->dev == dev &&
833 net_eq(pneigh_net(n), net)) {
834 *np = n->next;
835 write_unlock_bh(&tbl->lock);
836 if (tbl->pdestructor)
837 tbl->pdestructor(n);
838 netdev_put(n->dev, &n->dev_tracker);
839 kfree(n);
840 return 0;
841 }
842 }
843 write_unlock_bh(&tbl->lock);
844 return -ENOENT;
845}
846
847static int pneigh_ifdown_and_unlock(struct neigh_table *tbl,
848 struct net_device *dev)
849{
850 struct pneigh_entry *n, **np, *freelist = NULL;
851 u32 h;
852
853 for (h = 0; h <= PNEIGH_HASHMASK; h++) {
854 np = &tbl->phash_buckets[h];
855 while ((n = *np) != NULL) {
856 if (!dev || n->dev == dev) {
857 *np = n->next;
858 n->next = freelist;
859 freelist = n;
860 continue;
861 }
862 np = &n->next;
863 }
864 }
865 write_unlock_bh(&tbl->lock);
866 while ((n = freelist)) {
867 freelist = n->next;
868 n->next = NULL;
869 if (tbl->pdestructor)
870 tbl->pdestructor(n);
871 netdev_put(n->dev, &n->dev_tracker);
872 kfree(n);
873 }
874 return -ENOENT;
875}
876
877static void neigh_parms_destroy(struct neigh_parms *parms);
878
879static inline void neigh_parms_put(struct neigh_parms *parms)
880{
881 if (refcount_dec_and_test(&parms->refcnt))
882 neigh_parms_destroy(parms);
883}
884
885/*
886 * neighbour must already be out of the table;
887 *
888 */
889void neigh_destroy(struct neighbour *neigh)
890{
891 struct net_device *dev = neigh->dev;
892
893 NEIGH_CACHE_STAT_INC(neigh->tbl, destroys);
894
895 if (!neigh->dead) {
896 pr_warn("Destroying alive neighbour %p\n", neigh);
897 dump_stack();
898 return;
899 }
900
901 if (neigh_del_timer(neigh))
902 pr_warn("Impossible event\n");
903
904 write_lock_bh(&neigh->lock);
905 __skb_queue_purge(&neigh->arp_queue);
906 write_unlock_bh(&neigh->lock);
907 neigh->arp_queue_len_bytes = 0;
908
909 if (dev->netdev_ops->ndo_neigh_destroy)
910 dev->netdev_ops->ndo_neigh_destroy(dev, neigh);
911
912 netdev_put(dev, &neigh->dev_tracker);
913 neigh_parms_put(neigh->parms);
914
915 neigh_dbg(2, "neigh %p is destroyed\n", neigh);
916
917 atomic_dec(&neigh->tbl->entries);
918 kfree_rcu(neigh, rcu);
919}
920EXPORT_SYMBOL(neigh_destroy);
921
922/* Neighbour state is suspicious;
923 disable fast path.
924
925 Called with write_locked neigh.
926 */
927static void neigh_suspect(struct neighbour *neigh)
928{
929 neigh_dbg(2, "neigh %p is suspected\n", neigh);
930
931 WRITE_ONCE(neigh->output, neigh->ops->output);
932}
933
934/* Neighbour state is OK;
935 enable fast path.
936
937 Called with write_locked neigh.
938 */
939static void neigh_connect(struct neighbour *neigh)
940{
941 neigh_dbg(2, "neigh %p is connected\n", neigh);
942
943 WRITE_ONCE(neigh->output, neigh->ops->connected_output);
944}
945
946static void neigh_periodic_work(struct work_struct *work)
947{
948 struct neigh_table *tbl = container_of(work, struct neigh_table, gc_work.work);
949 struct neighbour *n;
950 struct neighbour __rcu **np;
951 unsigned int i;
952 struct neigh_hash_table *nht;
953
954 NEIGH_CACHE_STAT_INC(tbl, periodic_gc_runs);
955
956 write_lock_bh(&tbl->lock);
957 nht = rcu_dereference_protected(tbl->nht,
958 lockdep_is_held(&tbl->lock));
959
960 /*
961 * periodically recompute ReachableTime from random function
962 */
963
964 if (time_after(jiffies, tbl->last_rand + 300 * HZ)) {
965 struct neigh_parms *p;
966
967 WRITE_ONCE(tbl->last_rand, jiffies);
968 list_for_each_entry(p, &tbl->parms_list, list)
969 p->reachable_time =
970 neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME));
971 }
972
973 if (atomic_read(&tbl->entries) < READ_ONCE(tbl->gc_thresh1))
974 goto out;
975
976 for (i = 0 ; i < (1 << nht->hash_shift); i++) {
977 np = &nht->hash_buckets[i];
978
979 while ((n = rcu_dereference_protected(*np,
980 lockdep_is_held(&tbl->lock))) != NULL) {
981 unsigned int state;
982
983 write_lock(&n->lock);
984
985 state = n->nud_state;
986 if ((state & (NUD_PERMANENT | NUD_IN_TIMER)) ||
987 (n->flags & NTF_EXT_LEARNED)) {
988 write_unlock(&n->lock);
989 goto next_elt;
990 }
991
992 if (time_before(n->used, n->confirmed) &&
993 time_is_before_eq_jiffies(n->confirmed))
994 n->used = n->confirmed;
995
996 if (refcount_read(&n->refcnt) == 1 &&
997 (state == NUD_FAILED ||
998 !time_in_range_open(jiffies, n->used,
999 n->used + NEIGH_VAR(n->parms, GC_STALETIME)))) {
1000 rcu_assign_pointer(*np,
1001 rcu_dereference_protected(n->next,
1002 lockdep_is_held(&tbl->lock)));
1003 neigh_mark_dead(n);
1004 write_unlock(&n->lock);
1005 neigh_cleanup_and_release(n);
1006 continue;
1007 }
1008 write_unlock(&n->lock);
1009
1010next_elt:
1011 np = &n->next;
1012 }
1013 /*
1014 * It's fine to release lock here, even if hash table
1015 * grows while we are preempted.
1016 */
1017 write_unlock_bh(&tbl->lock);
1018 cond_resched();
1019 write_lock_bh(&tbl->lock);
1020 nht = rcu_dereference_protected(tbl->nht,
1021 lockdep_is_held(&tbl->lock));
1022 }
1023out:
1024 /* Cycle through all hash buckets every BASE_REACHABLE_TIME/2 ticks.
1025 * ARP entry timeouts range from 1/2 BASE_REACHABLE_TIME to 3/2
1026 * BASE_REACHABLE_TIME.
1027 */
1028 queue_delayed_work(system_power_efficient_wq, &tbl->gc_work,
1029 NEIGH_VAR(&tbl->parms, BASE_REACHABLE_TIME) >> 1);
1030 write_unlock_bh(&tbl->lock);
1031}
1032
1033static __inline__ int neigh_max_probes(struct neighbour *n)
1034{
1035 struct neigh_parms *p = n->parms;
1036 return NEIGH_VAR(p, UCAST_PROBES) + NEIGH_VAR(p, APP_PROBES) +
1037 (n->nud_state & NUD_PROBE ? NEIGH_VAR(p, MCAST_REPROBES) :
1038 NEIGH_VAR(p, MCAST_PROBES));
1039}
1040
1041static void neigh_invalidate(struct neighbour *neigh)
1042 __releases(neigh->lock)
1043 __acquires(neigh->lock)
1044{
1045 struct sk_buff *skb;
1046
1047 NEIGH_CACHE_STAT_INC(neigh->tbl, res_failed);
1048 neigh_dbg(2, "neigh %p is failed\n", neigh);
1049 neigh->updated = jiffies;
1050
1051 /* It is very thin place. report_unreachable is very complicated
1052 routine. Particularly, it can hit the same neighbour entry!
1053
1054 So that, we try to be accurate and avoid dead loop. --ANK
1055 */
1056 while (neigh->nud_state == NUD_FAILED &&
1057 (skb = __skb_dequeue(&neigh->arp_queue)) != NULL) {
1058 write_unlock(&neigh->lock);
1059 neigh->ops->error_report(neigh, skb);
1060 write_lock(&neigh->lock);
1061 }
1062 __skb_queue_purge(&neigh->arp_queue);
1063 neigh->arp_queue_len_bytes = 0;
1064}
1065
1066static void neigh_probe(struct neighbour *neigh)
1067 __releases(neigh->lock)
1068{
1069 struct sk_buff *skb = skb_peek_tail(&neigh->arp_queue);
1070 /* keep skb alive even if arp_queue overflows */
1071 if (skb)
1072 skb = skb_clone(skb, GFP_ATOMIC);
1073 write_unlock(&neigh->lock);
1074 if (neigh->ops->solicit)
1075 neigh->ops->solicit(neigh, skb);
1076 atomic_inc(&neigh->probes);
1077 consume_skb(skb);
1078}
1079
1080/* Called when a timer expires for a neighbour entry. */
1081
1082static void neigh_timer_handler(struct timer_list *t)
1083{
1084 unsigned long now, next;
1085 struct neighbour *neigh = from_timer(neigh, t, timer);
1086 unsigned int state;
1087 int notify = 0;
1088
1089 write_lock(&neigh->lock);
1090
1091 state = neigh->nud_state;
1092 now = jiffies;
1093 next = now + HZ;
1094
1095 if (!(state & NUD_IN_TIMER))
1096 goto out;
1097
1098 if (state & NUD_REACHABLE) {
1099 if (time_before_eq(now,
1100 neigh->confirmed + neigh->parms->reachable_time)) {
1101 neigh_dbg(2, "neigh %p is still alive\n", neigh);
1102 next = neigh->confirmed + neigh->parms->reachable_time;
1103 } else if (time_before_eq(now,
1104 neigh->used +
1105 NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME))) {
1106 neigh_dbg(2, "neigh %p is delayed\n", neigh);
1107 WRITE_ONCE(neigh->nud_state, NUD_DELAY);
1108 neigh->updated = jiffies;
1109 neigh_suspect(neigh);
1110 next = now + NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME);
1111 } else {
1112 neigh_dbg(2, "neigh %p is suspected\n", neigh);
1113 WRITE_ONCE(neigh->nud_state, NUD_STALE);
1114 neigh->updated = jiffies;
1115 neigh_suspect(neigh);
1116 notify = 1;
1117 }
1118 } else if (state & NUD_DELAY) {
1119 if (time_before_eq(now,
1120 neigh->confirmed +
1121 NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME))) {
1122 neigh_dbg(2, "neigh %p is now reachable\n", neigh);
1123 WRITE_ONCE(neigh->nud_state, NUD_REACHABLE);
1124 neigh->updated = jiffies;
1125 neigh_connect(neigh);
1126 notify = 1;
1127 next = neigh->confirmed + neigh->parms->reachable_time;
1128 } else {
1129 neigh_dbg(2, "neigh %p is probed\n", neigh);
1130 WRITE_ONCE(neigh->nud_state, NUD_PROBE);
1131 neigh->updated = jiffies;
1132 atomic_set(&neigh->probes, 0);
1133 notify = 1;
1134 next = now + max(NEIGH_VAR(neigh->parms, RETRANS_TIME),
1135 HZ/100);
1136 }
1137 } else {
1138 /* NUD_PROBE|NUD_INCOMPLETE */
1139 next = now + max(NEIGH_VAR(neigh->parms, RETRANS_TIME), HZ/100);
1140 }
1141
1142 if ((neigh->nud_state & (NUD_INCOMPLETE | NUD_PROBE)) &&
1143 atomic_read(&neigh->probes) >= neigh_max_probes(neigh)) {
1144 WRITE_ONCE(neigh->nud_state, NUD_FAILED);
1145 notify = 1;
1146 neigh_invalidate(neigh);
1147 goto out;
1148 }
1149
1150 if (neigh->nud_state & NUD_IN_TIMER) {
1151 if (time_before(next, jiffies + HZ/100))
1152 next = jiffies + HZ/100;
1153 if (!mod_timer(&neigh->timer, next))
1154 neigh_hold(neigh);
1155 }
1156 if (neigh->nud_state & (NUD_INCOMPLETE | NUD_PROBE)) {
1157 neigh_probe(neigh);
1158 } else {
1159out:
1160 write_unlock(&neigh->lock);
1161 }
1162
1163 if (notify)
1164 neigh_update_notify(neigh, 0);
1165
1166 trace_neigh_timer_handler(neigh, 0);
1167
1168 neigh_release(neigh);
1169}
1170
1171int __neigh_event_send(struct neighbour *neigh, struct sk_buff *skb,
1172 const bool immediate_ok)
1173{
1174 int rc;
1175 bool immediate_probe = false;
1176
1177 write_lock_bh(&neigh->lock);
1178
1179 rc = 0;
1180 if (neigh->nud_state & (NUD_CONNECTED | NUD_DELAY | NUD_PROBE))
1181 goto out_unlock_bh;
1182 if (neigh->dead)
1183 goto out_dead;
1184
1185 if (!(neigh->nud_state & (NUD_STALE | NUD_INCOMPLETE))) {
1186 if (NEIGH_VAR(neigh->parms, MCAST_PROBES) +
1187 NEIGH_VAR(neigh->parms, APP_PROBES)) {
1188 unsigned long next, now = jiffies;
1189
1190 atomic_set(&neigh->probes,
1191 NEIGH_VAR(neigh->parms, UCAST_PROBES));
1192 neigh_del_timer(neigh);
1193 WRITE_ONCE(neigh->nud_state, NUD_INCOMPLETE);
1194 neigh->updated = now;
1195 if (!immediate_ok) {
1196 next = now + 1;
1197 } else {
1198 immediate_probe = true;
1199 next = now + max(NEIGH_VAR(neigh->parms,
1200 RETRANS_TIME),
1201 HZ / 100);
1202 }
1203 neigh_add_timer(neigh, next);
1204 } else {
1205 WRITE_ONCE(neigh->nud_state, NUD_FAILED);
1206 neigh->updated = jiffies;
1207 write_unlock_bh(&neigh->lock);
1208
1209 kfree_skb_reason(skb, SKB_DROP_REASON_NEIGH_FAILED);
1210 return 1;
1211 }
1212 } else if (neigh->nud_state & NUD_STALE) {
1213 neigh_dbg(2, "neigh %p is delayed\n", neigh);
1214 neigh_del_timer(neigh);
1215 WRITE_ONCE(neigh->nud_state, NUD_DELAY);
1216 neigh->updated = jiffies;
1217 neigh_add_timer(neigh, jiffies +
1218 NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME));
1219 }
1220
1221 if (neigh->nud_state == NUD_INCOMPLETE) {
1222 if (skb) {
1223 while (neigh->arp_queue_len_bytes + skb->truesize >
1224 NEIGH_VAR(neigh->parms, QUEUE_LEN_BYTES)) {
1225 struct sk_buff *buff;
1226
1227 buff = __skb_dequeue(&neigh->arp_queue);
1228 if (!buff)
1229 break;
1230 neigh->arp_queue_len_bytes -= buff->truesize;
1231 kfree_skb_reason(buff, SKB_DROP_REASON_NEIGH_QUEUEFULL);
1232 NEIGH_CACHE_STAT_INC(neigh->tbl, unres_discards);
1233 }
1234 skb_dst_force(skb);
1235 __skb_queue_tail(&neigh->arp_queue, skb);
1236 neigh->arp_queue_len_bytes += skb->truesize;
1237 }
1238 rc = 1;
1239 }
1240out_unlock_bh:
1241 if (immediate_probe)
1242 neigh_probe(neigh);
1243 else
1244 write_unlock(&neigh->lock);
1245 local_bh_enable();
1246 trace_neigh_event_send_done(neigh, rc);
1247 return rc;
1248
1249out_dead:
1250 if (neigh->nud_state & NUD_STALE)
1251 goto out_unlock_bh;
1252 write_unlock_bh(&neigh->lock);
1253 kfree_skb_reason(skb, SKB_DROP_REASON_NEIGH_DEAD);
1254 trace_neigh_event_send_dead(neigh, 1);
1255 return 1;
1256}
1257EXPORT_SYMBOL(__neigh_event_send);
1258
1259static void neigh_update_hhs(struct neighbour *neigh)
1260{
1261 struct hh_cache *hh;
1262 void (*update)(struct hh_cache*, const struct net_device*, const unsigned char *)
1263 = NULL;
1264
1265 if (neigh->dev->header_ops)
1266 update = neigh->dev->header_ops->cache_update;
1267
1268 if (update) {
1269 hh = &neigh->hh;
1270 if (READ_ONCE(hh->hh_len)) {
1271 write_seqlock_bh(&hh->hh_lock);
1272 update(hh, neigh->dev, neigh->ha);
1273 write_sequnlock_bh(&hh->hh_lock);
1274 }
1275 }
1276}
1277
1278/* Generic update routine.
1279 -- lladdr is new lladdr or NULL, if it is not supplied.
1280 -- new is new state.
1281 -- flags
1282 NEIGH_UPDATE_F_OVERRIDE allows to override existing lladdr,
1283 if it is different.
1284 NEIGH_UPDATE_F_WEAK_OVERRIDE will suspect existing "connected"
1285 lladdr instead of overriding it
1286 if it is different.
1287 NEIGH_UPDATE_F_ADMIN means that the change is administrative.
1288 NEIGH_UPDATE_F_USE means that the entry is user triggered.
1289 NEIGH_UPDATE_F_MANAGED means that the entry will be auto-refreshed.
1290 NEIGH_UPDATE_F_OVERRIDE_ISROUTER allows to override existing
1291 NTF_ROUTER flag.
1292 NEIGH_UPDATE_F_ISROUTER indicates if the neighbour is known as
1293 a router.
1294
1295 Caller MUST hold reference count on the entry.
1296 */
1297static int __neigh_update(struct neighbour *neigh, const u8 *lladdr,
1298 u8 new, u32 flags, u32 nlmsg_pid,
1299 struct netlink_ext_ack *extack)
1300{
1301 bool gc_update = false, managed_update = false;
1302 int update_isrouter = 0;
1303 struct net_device *dev;
1304 int err, notify = 0;
1305 u8 old;
1306
1307 trace_neigh_update(neigh, lladdr, new, flags, nlmsg_pid);
1308
1309 write_lock_bh(&neigh->lock);
1310
1311 dev = neigh->dev;
1312 old = neigh->nud_state;
1313 err = -EPERM;
1314
1315 if (neigh->dead) {
1316 NL_SET_ERR_MSG(extack, "Neighbor entry is now dead");
1317 new = old;
1318 goto out;
1319 }
1320 if (!(flags & NEIGH_UPDATE_F_ADMIN) &&
1321 (old & (NUD_NOARP | NUD_PERMANENT)))
1322 goto out;
1323
1324 neigh_update_flags(neigh, flags, ¬ify, &gc_update, &managed_update);
1325 if (flags & (NEIGH_UPDATE_F_USE | NEIGH_UPDATE_F_MANAGED)) {
1326 new = old & ~NUD_PERMANENT;
1327 WRITE_ONCE(neigh->nud_state, new);
1328 err = 0;
1329 goto out;
1330 }
1331
1332 if (!(new & NUD_VALID)) {
1333 neigh_del_timer(neigh);
1334 if (old & NUD_CONNECTED)
1335 neigh_suspect(neigh);
1336 WRITE_ONCE(neigh->nud_state, new);
1337 err = 0;
1338 notify = old & NUD_VALID;
1339 if ((old & (NUD_INCOMPLETE | NUD_PROBE)) &&
1340 (new & NUD_FAILED)) {
1341 neigh_invalidate(neigh);
1342 notify = 1;
1343 }
1344 goto out;
1345 }
1346
1347 /* Compare new lladdr with cached one */
1348 if (!dev->addr_len) {
1349 /* First case: device needs no address. */
1350 lladdr = neigh->ha;
1351 } else if (lladdr) {
1352 /* The second case: if something is already cached
1353 and a new address is proposed:
1354 - compare new & old
1355 - if they are different, check override flag
1356 */
1357 if ((old & NUD_VALID) &&
1358 !memcmp(lladdr, neigh->ha, dev->addr_len))
1359 lladdr = neigh->ha;
1360 } else {
1361 /* No address is supplied; if we know something,
1362 use it, otherwise discard the request.
1363 */
1364 err = -EINVAL;
1365 if (!(old & NUD_VALID)) {
1366 NL_SET_ERR_MSG(extack, "No link layer address given");
1367 goto out;
1368 }
1369 lladdr = neigh->ha;
1370 }
1371
1372 /* Update confirmed timestamp for neighbour entry after we
1373 * received ARP packet even if it doesn't change IP to MAC binding.
1374 */
1375 if (new & NUD_CONNECTED)
1376 neigh->confirmed = jiffies;
1377
1378 /* If entry was valid and address is not changed,
1379 do not change entry state, if new one is STALE.
1380 */
1381 err = 0;
1382 update_isrouter = flags & NEIGH_UPDATE_F_OVERRIDE_ISROUTER;
1383 if (old & NUD_VALID) {
1384 if (lladdr != neigh->ha && !(flags & NEIGH_UPDATE_F_OVERRIDE)) {
1385 update_isrouter = 0;
1386 if ((flags & NEIGH_UPDATE_F_WEAK_OVERRIDE) &&
1387 (old & NUD_CONNECTED)) {
1388 lladdr = neigh->ha;
1389 new = NUD_STALE;
1390 } else
1391 goto out;
1392 } else {
1393 if (lladdr == neigh->ha && new == NUD_STALE &&
1394 !(flags & NEIGH_UPDATE_F_ADMIN))
1395 new = old;
1396 }
1397 }
1398
1399 /* Update timestamp only once we know we will make a change to the
1400 * neighbour entry. Otherwise we risk to move the locktime window with
1401 * noop updates and ignore relevant ARP updates.
1402 */
1403 if (new != old || lladdr != neigh->ha)
1404 neigh->updated = jiffies;
1405
1406 if (new != old) {
1407 neigh_del_timer(neigh);
1408 if (new & NUD_PROBE)
1409 atomic_set(&neigh->probes, 0);
1410 if (new & NUD_IN_TIMER)
1411 neigh_add_timer(neigh, (jiffies +
1412 ((new & NUD_REACHABLE) ?
1413 neigh->parms->reachable_time :
1414 0)));
1415 WRITE_ONCE(neigh->nud_state, new);
1416 notify = 1;
1417 }
1418
1419 if (lladdr != neigh->ha) {
1420 write_seqlock(&neigh->ha_lock);
1421 memcpy(&neigh->ha, lladdr, dev->addr_len);
1422 write_sequnlock(&neigh->ha_lock);
1423 neigh_update_hhs(neigh);
1424 if (!(new & NUD_CONNECTED))
1425 neigh->confirmed = jiffies -
1426 (NEIGH_VAR(neigh->parms, BASE_REACHABLE_TIME) << 1);
1427 notify = 1;
1428 }
1429 if (new == old)
1430 goto out;
1431 if (new & NUD_CONNECTED)
1432 neigh_connect(neigh);
1433 else
1434 neigh_suspect(neigh);
1435 if (!(old & NUD_VALID)) {
1436 struct sk_buff *skb;
1437
1438 /* Again: avoid dead loop if something went wrong */
1439
1440 while (neigh->nud_state & NUD_VALID &&
1441 (skb = __skb_dequeue(&neigh->arp_queue)) != NULL) {
1442 struct dst_entry *dst = skb_dst(skb);
1443 struct neighbour *n2, *n1 = neigh;
1444 write_unlock_bh(&neigh->lock);
1445
1446 rcu_read_lock();
1447
1448 /* Why not just use 'neigh' as-is? The problem is that
1449 * things such as shaper, eql, and sch_teql can end up
1450 * using alternative, different, neigh objects to output
1451 * the packet in the output path. So what we need to do
1452 * here is re-lookup the top-level neigh in the path so
1453 * we can reinject the packet there.
1454 */
1455 n2 = NULL;
1456 if (dst && dst->obsolete != DST_OBSOLETE_DEAD) {
1457 n2 = dst_neigh_lookup_skb(dst, skb);
1458 if (n2)
1459 n1 = n2;
1460 }
1461 READ_ONCE(n1->output)(n1, skb);
1462 if (n2)
1463 neigh_release(n2);
1464 rcu_read_unlock();
1465
1466 write_lock_bh(&neigh->lock);
1467 }
1468 __skb_queue_purge(&neigh->arp_queue);
1469 neigh->arp_queue_len_bytes = 0;
1470 }
1471out:
1472 if (update_isrouter)
1473 neigh_update_is_router(neigh, flags, ¬ify);
1474 write_unlock_bh(&neigh->lock);
1475 if (((new ^ old) & NUD_PERMANENT) || gc_update)
1476 neigh_update_gc_list(neigh);
1477 if (managed_update)
1478 neigh_update_managed_list(neigh);
1479 if (notify)
1480 neigh_update_notify(neigh, nlmsg_pid);
1481 trace_neigh_update_done(neigh, err);
1482 return err;
1483}
1484
1485int neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new,
1486 u32 flags, u32 nlmsg_pid)
1487{
1488 return __neigh_update(neigh, lladdr, new, flags, nlmsg_pid, NULL);
1489}
1490EXPORT_SYMBOL(neigh_update);
1491
1492/* Update the neigh to listen temporarily for probe responses, even if it is
1493 * in a NUD_FAILED state. The caller has to hold neigh->lock for writing.
1494 */
1495void __neigh_set_probe_once(struct neighbour *neigh)
1496{
1497 if (neigh->dead)
1498 return;
1499 neigh->updated = jiffies;
1500 if (!(neigh->nud_state & NUD_FAILED))
1501 return;
1502 WRITE_ONCE(neigh->nud_state, NUD_INCOMPLETE);
1503 atomic_set(&neigh->probes, neigh_max_probes(neigh));
1504 neigh_add_timer(neigh,
1505 jiffies + max(NEIGH_VAR(neigh->parms, RETRANS_TIME),
1506 HZ/100));
1507}
1508EXPORT_SYMBOL(__neigh_set_probe_once);
1509
1510struct neighbour *neigh_event_ns(struct neigh_table *tbl,
1511 u8 *lladdr, void *saddr,
1512 struct net_device *dev)
1513{
1514 struct neighbour *neigh = __neigh_lookup(tbl, saddr, dev,
1515 lladdr || !dev->addr_len);
1516 if (neigh)
1517 neigh_update(neigh, lladdr, NUD_STALE,
1518 NEIGH_UPDATE_F_OVERRIDE, 0);
1519 return neigh;
1520}
1521EXPORT_SYMBOL(neigh_event_ns);
1522
1523/* called with read_lock_bh(&n->lock); */
1524static void neigh_hh_init(struct neighbour *n)
1525{
1526 struct net_device *dev = n->dev;
1527 __be16 prot = n->tbl->protocol;
1528 struct hh_cache *hh = &n->hh;
1529
1530 write_lock_bh(&n->lock);
1531
1532 /* Only one thread can come in here and initialize the
1533 * hh_cache entry.
1534 */
1535 if (!hh->hh_len)
1536 dev->header_ops->cache(n, hh, prot);
1537
1538 write_unlock_bh(&n->lock);
1539}
1540
1541/* Slow and careful. */
1542
1543int neigh_resolve_output(struct neighbour *neigh, struct sk_buff *skb)
1544{
1545 int rc = 0;
1546
1547 if (!neigh_event_send(neigh, skb)) {
1548 int err;
1549 struct net_device *dev = neigh->dev;
1550 unsigned int seq;
1551
1552 if (dev->header_ops->cache && !READ_ONCE(neigh->hh.hh_len))
1553 neigh_hh_init(neigh);
1554
1555 do {
1556 __skb_pull(skb, skb_network_offset(skb));
1557 seq = read_seqbegin(&neigh->ha_lock);
1558 err = dev_hard_header(skb, dev, ntohs(skb->protocol),
1559 neigh->ha, NULL, skb->len);
1560 } while (read_seqretry(&neigh->ha_lock, seq));
1561
1562 if (err >= 0)
1563 rc = dev_queue_xmit(skb);
1564 else
1565 goto out_kfree_skb;
1566 }
1567out:
1568 return rc;
1569out_kfree_skb:
1570 rc = -EINVAL;
1571 kfree_skb(skb);
1572 goto out;
1573}
1574EXPORT_SYMBOL(neigh_resolve_output);
1575
1576/* As fast as possible without hh cache */
1577
1578int neigh_connected_output(struct neighbour *neigh, struct sk_buff *skb)
1579{
1580 struct net_device *dev = neigh->dev;
1581 unsigned int seq;
1582 int err;
1583
1584 do {
1585 __skb_pull(skb, skb_network_offset(skb));
1586 seq = read_seqbegin(&neigh->ha_lock);
1587 err = dev_hard_header(skb, dev, ntohs(skb->protocol),
1588 neigh->ha, NULL, skb->len);
1589 } while (read_seqretry(&neigh->ha_lock, seq));
1590
1591 if (err >= 0)
1592 err = dev_queue_xmit(skb);
1593 else {
1594 err = -EINVAL;
1595 kfree_skb(skb);
1596 }
1597 return err;
1598}
1599EXPORT_SYMBOL(neigh_connected_output);
1600
1601int neigh_direct_output(struct neighbour *neigh, struct sk_buff *skb)
1602{
1603 return dev_queue_xmit(skb);
1604}
1605EXPORT_SYMBOL(neigh_direct_output);
1606
1607static void neigh_managed_work(struct work_struct *work)
1608{
1609 struct neigh_table *tbl = container_of(work, struct neigh_table,
1610 managed_work.work);
1611 struct neighbour *neigh;
1612
1613 write_lock_bh(&tbl->lock);
1614 list_for_each_entry(neigh, &tbl->managed_list, managed_list)
1615 neigh_event_send_probe(neigh, NULL, false);
1616 queue_delayed_work(system_power_efficient_wq, &tbl->managed_work,
1617 NEIGH_VAR(&tbl->parms, INTERVAL_PROBE_TIME_MS));
1618 write_unlock_bh(&tbl->lock);
1619}
1620
1621static void neigh_proxy_process(struct timer_list *t)
1622{
1623 struct neigh_table *tbl = from_timer(tbl, t, proxy_timer);
1624 long sched_next = 0;
1625 unsigned long now = jiffies;
1626 struct sk_buff *skb, *n;
1627
1628 spin_lock(&tbl->proxy_queue.lock);
1629
1630 skb_queue_walk_safe(&tbl->proxy_queue, skb, n) {
1631 long tdif = NEIGH_CB(skb)->sched_next - now;
1632
1633 if (tdif <= 0) {
1634 struct net_device *dev = skb->dev;
1635
1636 neigh_parms_qlen_dec(dev, tbl->family);
1637 __skb_unlink(skb, &tbl->proxy_queue);
1638
1639 if (tbl->proxy_redo && netif_running(dev)) {
1640 rcu_read_lock();
1641 tbl->proxy_redo(skb);
1642 rcu_read_unlock();
1643 } else {
1644 kfree_skb(skb);
1645 }
1646
1647 dev_put(dev);
1648 } else if (!sched_next || tdif < sched_next)
1649 sched_next = tdif;
1650 }
1651 del_timer(&tbl->proxy_timer);
1652 if (sched_next)
1653 mod_timer(&tbl->proxy_timer, jiffies + sched_next);
1654 spin_unlock(&tbl->proxy_queue.lock);
1655}
1656
1657static unsigned long neigh_proxy_delay(struct neigh_parms *p)
1658{
1659 /* If proxy_delay is zero, do not call get_random_u32_below()
1660 * as it is undefined behavior.
1661 */
1662 unsigned long proxy_delay = NEIGH_VAR(p, PROXY_DELAY);
1663
1664 return proxy_delay ?
1665 jiffies + get_random_u32_below(proxy_delay) : jiffies;
1666}
1667
1668void pneigh_enqueue(struct neigh_table *tbl, struct neigh_parms *p,
1669 struct sk_buff *skb)
1670{
1671 unsigned long sched_next = neigh_proxy_delay(p);
1672
1673 if (p->qlen > NEIGH_VAR(p, PROXY_QLEN)) {
1674 kfree_skb(skb);
1675 return;
1676 }
1677
1678 NEIGH_CB(skb)->sched_next = sched_next;
1679 NEIGH_CB(skb)->flags |= LOCALLY_ENQUEUED;
1680
1681 spin_lock(&tbl->proxy_queue.lock);
1682 if (del_timer(&tbl->proxy_timer)) {
1683 if (time_before(tbl->proxy_timer.expires, sched_next))
1684 sched_next = tbl->proxy_timer.expires;
1685 }
1686 skb_dst_drop(skb);
1687 dev_hold(skb->dev);
1688 __skb_queue_tail(&tbl->proxy_queue, skb);
1689 p->qlen++;
1690 mod_timer(&tbl->proxy_timer, sched_next);
1691 spin_unlock(&tbl->proxy_queue.lock);
1692}
1693EXPORT_SYMBOL(pneigh_enqueue);
1694
1695static inline struct neigh_parms *lookup_neigh_parms(struct neigh_table *tbl,
1696 struct net *net, int ifindex)
1697{
1698 struct neigh_parms *p;
1699
1700 list_for_each_entry(p, &tbl->parms_list, list) {
1701 if ((p->dev && p->dev->ifindex == ifindex && net_eq(neigh_parms_net(p), net)) ||
1702 (!p->dev && !ifindex && net_eq(net, &init_net)))
1703 return p;
1704 }
1705
1706 return NULL;
1707}
1708
1709struct neigh_parms *neigh_parms_alloc(struct net_device *dev,
1710 struct neigh_table *tbl)
1711{
1712 struct neigh_parms *p;
1713 struct net *net = dev_net(dev);
1714 const struct net_device_ops *ops = dev->netdev_ops;
1715
1716 p = kmemdup(&tbl->parms, sizeof(*p), GFP_KERNEL);
1717 if (p) {
1718 p->tbl = tbl;
1719 refcount_set(&p->refcnt, 1);
1720 p->reachable_time =
1721 neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME));
1722 p->qlen = 0;
1723 netdev_hold(dev, &p->dev_tracker, GFP_KERNEL);
1724 p->dev = dev;
1725 write_pnet(&p->net, net);
1726 p->sysctl_table = NULL;
1727
1728 if (ops->ndo_neigh_setup && ops->ndo_neigh_setup(dev, p)) {
1729 netdev_put(dev, &p->dev_tracker);
1730 kfree(p);
1731 return NULL;
1732 }
1733
1734 write_lock_bh(&tbl->lock);
1735 list_add(&p->list, &tbl->parms.list);
1736 write_unlock_bh(&tbl->lock);
1737
1738 neigh_parms_data_state_cleanall(p);
1739 }
1740 return p;
1741}
1742EXPORT_SYMBOL(neigh_parms_alloc);
1743
1744static void neigh_rcu_free_parms(struct rcu_head *head)
1745{
1746 struct neigh_parms *parms =
1747 container_of(head, struct neigh_parms, rcu_head);
1748
1749 neigh_parms_put(parms);
1750}
1751
1752void neigh_parms_release(struct neigh_table *tbl, struct neigh_parms *parms)
1753{
1754 if (!parms || parms == &tbl->parms)
1755 return;
1756 write_lock_bh(&tbl->lock);
1757 list_del(&parms->list);
1758 parms->dead = 1;
1759 write_unlock_bh(&tbl->lock);
1760 netdev_put(parms->dev, &parms->dev_tracker);
1761 call_rcu(&parms->rcu_head, neigh_rcu_free_parms);
1762}
1763EXPORT_SYMBOL(neigh_parms_release);
1764
1765static void neigh_parms_destroy(struct neigh_parms *parms)
1766{
1767 kfree(parms);
1768}
1769
1770static struct lock_class_key neigh_table_proxy_queue_class;
1771
1772static struct neigh_table *neigh_tables[NEIGH_NR_TABLES] __read_mostly;
1773
1774void neigh_table_init(int index, struct neigh_table *tbl)
1775{
1776 unsigned long now = jiffies;
1777 unsigned long phsize;
1778
1779 INIT_LIST_HEAD(&tbl->parms_list);
1780 INIT_LIST_HEAD(&tbl->gc_list);
1781 INIT_LIST_HEAD(&tbl->managed_list);
1782
1783 list_add(&tbl->parms.list, &tbl->parms_list);
1784 write_pnet(&tbl->parms.net, &init_net);
1785 refcount_set(&tbl->parms.refcnt, 1);
1786 tbl->parms.reachable_time =
1787 neigh_rand_reach_time(NEIGH_VAR(&tbl->parms, BASE_REACHABLE_TIME));
1788 tbl->parms.qlen = 0;
1789
1790 tbl->stats = alloc_percpu(struct neigh_statistics);
1791 if (!tbl->stats)
1792 panic("cannot create neighbour cache statistics");
1793
1794#ifdef CONFIG_PROC_FS
1795 if (!proc_create_seq_data(tbl->id, 0, init_net.proc_net_stat,
1796 &neigh_stat_seq_ops, tbl))
1797 panic("cannot create neighbour proc dir entry");
1798#endif
1799
1800 RCU_INIT_POINTER(tbl->nht, neigh_hash_alloc(3));
1801
1802 phsize = (PNEIGH_HASHMASK + 1) * sizeof(struct pneigh_entry *);
1803 tbl->phash_buckets = kzalloc(phsize, GFP_KERNEL);
1804
1805 if (!tbl->nht || !tbl->phash_buckets)
1806 panic("cannot allocate neighbour cache hashes");
1807
1808 if (!tbl->entry_size)
1809 tbl->entry_size = ALIGN(offsetof(struct neighbour, primary_key) +
1810 tbl->key_len, NEIGH_PRIV_ALIGN);
1811 else
1812 WARN_ON(tbl->entry_size % NEIGH_PRIV_ALIGN);
1813
1814 rwlock_init(&tbl->lock);
1815
1816 INIT_DEFERRABLE_WORK(&tbl->gc_work, neigh_periodic_work);
1817 queue_delayed_work(system_power_efficient_wq, &tbl->gc_work,
1818 tbl->parms.reachable_time);
1819 INIT_DEFERRABLE_WORK(&tbl->managed_work, neigh_managed_work);
1820 queue_delayed_work(system_power_efficient_wq, &tbl->managed_work, 0);
1821
1822 timer_setup(&tbl->proxy_timer, neigh_proxy_process, 0);
1823 skb_queue_head_init_class(&tbl->proxy_queue,
1824 &neigh_table_proxy_queue_class);
1825
1826 tbl->last_flush = now;
1827 tbl->last_rand = now + tbl->parms.reachable_time * 20;
1828
1829 neigh_tables[index] = tbl;
1830}
1831EXPORT_SYMBOL(neigh_table_init);
1832
1833int neigh_table_clear(int index, struct neigh_table *tbl)
1834{
1835 neigh_tables[index] = NULL;
1836 /* It is not clean... Fix it to unload IPv6 module safely */
1837 cancel_delayed_work_sync(&tbl->managed_work);
1838 cancel_delayed_work_sync(&tbl->gc_work);
1839 del_timer_sync(&tbl->proxy_timer);
1840 pneigh_queue_purge(&tbl->proxy_queue, NULL, tbl->family);
1841 neigh_ifdown(tbl, NULL);
1842 if (atomic_read(&tbl->entries))
1843 pr_crit("neighbour leakage\n");
1844
1845 call_rcu(&rcu_dereference_protected(tbl->nht, 1)->rcu,
1846 neigh_hash_free_rcu);
1847 tbl->nht = NULL;
1848
1849 kfree(tbl->phash_buckets);
1850 tbl->phash_buckets = NULL;
1851
1852 remove_proc_entry(tbl->id, init_net.proc_net_stat);
1853
1854 free_percpu(tbl->stats);
1855 tbl->stats = NULL;
1856
1857 return 0;
1858}
1859EXPORT_SYMBOL(neigh_table_clear);
1860
1861static struct neigh_table *neigh_find_table(int family)
1862{
1863 struct neigh_table *tbl = NULL;
1864
1865 switch (family) {
1866 case AF_INET:
1867 tbl = neigh_tables[NEIGH_ARP_TABLE];
1868 break;
1869 case AF_INET6:
1870 tbl = neigh_tables[NEIGH_ND_TABLE];
1871 break;
1872 }
1873
1874 return tbl;
1875}
1876
1877const struct nla_policy nda_policy[NDA_MAX+1] = {
1878 [NDA_UNSPEC] = { .strict_start_type = NDA_NH_ID },
1879 [NDA_DST] = { .type = NLA_BINARY, .len = MAX_ADDR_LEN },
1880 [NDA_LLADDR] = { .type = NLA_BINARY, .len = MAX_ADDR_LEN },
1881 [NDA_CACHEINFO] = { .len = sizeof(struct nda_cacheinfo) },
1882 [NDA_PROBES] = { .type = NLA_U32 },
1883 [NDA_VLAN] = { .type = NLA_U16 },
1884 [NDA_PORT] = { .type = NLA_U16 },
1885 [NDA_VNI] = { .type = NLA_U32 },
1886 [NDA_IFINDEX] = { .type = NLA_U32 },
1887 [NDA_MASTER] = { .type = NLA_U32 },
1888 [NDA_PROTOCOL] = { .type = NLA_U8 },
1889 [NDA_NH_ID] = { .type = NLA_U32 },
1890 [NDA_FLAGS_EXT] = NLA_POLICY_MASK(NLA_U32, NTF_EXT_MASK),
1891 [NDA_FDB_EXT_ATTRS] = { .type = NLA_NESTED },
1892};
1893
1894static int neigh_delete(struct sk_buff *skb, struct nlmsghdr *nlh,
1895 struct netlink_ext_ack *extack)
1896{
1897 struct net *net = sock_net(skb->sk);
1898 struct ndmsg *ndm;
1899 struct nlattr *dst_attr;
1900 struct neigh_table *tbl;
1901 struct neighbour *neigh;
1902 struct net_device *dev = NULL;
1903 int err = -EINVAL;
1904
1905 ASSERT_RTNL();
1906 if (nlmsg_len(nlh) < sizeof(*ndm))
1907 goto out;
1908
1909 dst_attr = nlmsg_find_attr(nlh, sizeof(*ndm), NDA_DST);
1910 if (!dst_attr) {
1911 NL_SET_ERR_MSG(extack, "Network address not specified");
1912 goto out;
1913 }
1914
1915 ndm = nlmsg_data(nlh);
1916 if (ndm->ndm_ifindex) {
1917 dev = __dev_get_by_index(net, ndm->ndm_ifindex);
1918 if (dev == NULL) {
1919 err = -ENODEV;
1920 goto out;
1921 }
1922 }
1923
1924 tbl = neigh_find_table(ndm->ndm_family);
1925 if (tbl == NULL)
1926 return -EAFNOSUPPORT;
1927
1928 if (nla_len(dst_attr) < (int)tbl->key_len) {
1929 NL_SET_ERR_MSG(extack, "Invalid network address");
1930 goto out;
1931 }
1932
1933 if (ndm->ndm_flags & NTF_PROXY) {
1934 err = pneigh_delete(tbl, net, nla_data(dst_attr), dev);
1935 goto out;
1936 }
1937
1938 if (dev == NULL)
1939 goto out;
1940
1941 neigh = neigh_lookup(tbl, nla_data(dst_attr), dev);
1942 if (neigh == NULL) {
1943 err = -ENOENT;
1944 goto out;
1945 }
1946
1947 err = __neigh_update(neigh, NULL, NUD_FAILED,
1948 NEIGH_UPDATE_F_OVERRIDE | NEIGH_UPDATE_F_ADMIN,
1949 NETLINK_CB(skb).portid, extack);
1950 write_lock_bh(&tbl->lock);
1951 neigh_release(neigh);
1952 neigh_remove_one(neigh, tbl);
1953 write_unlock_bh(&tbl->lock);
1954
1955out:
1956 return err;
1957}
1958
1959static int neigh_add(struct sk_buff *skb, struct nlmsghdr *nlh,
1960 struct netlink_ext_ack *extack)
1961{
1962 int flags = NEIGH_UPDATE_F_ADMIN | NEIGH_UPDATE_F_OVERRIDE |
1963 NEIGH_UPDATE_F_OVERRIDE_ISROUTER;
1964 struct net *net = sock_net(skb->sk);
1965 struct ndmsg *ndm;
1966 struct nlattr *tb[NDA_MAX+1];
1967 struct neigh_table *tbl;
1968 struct net_device *dev = NULL;
1969 struct neighbour *neigh;
1970 void *dst, *lladdr;
1971 u8 protocol = 0;
1972 u32 ndm_flags;
1973 int err;
1974
1975 ASSERT_RTNL();
1976 err = nlmsg_parse_deprecated(nlh, sizeof(*ndm), tb, NDA_MAX,
1977 nda_policy, extack);
1978 if (err < 0)
1979 goto out;
1980
1981 err = -EINVAL;
1982 if (!tb[NDA_DST]) {
1983 NL_SET_ERR_MSG(extack, "Network address not specified");
1984 goto out;
1985 }
1986
1987 ndm = nlmsg_data(nlh);
1988 ndm_flags = ndm->ndm_flags;
1989 if (tb[NDA_FLAGS_EXT]) {
1990 u32 ext = nla_get_u32(tb[NDA_FLAGS_EXT]);
1991
1992 BUILD_BUG_ON(sizeof(neigh->flags) * BITS_PER_BYTE <
1993 (sizeof(ndm->ndm_flags) * BITS_PER_BYTE +
1994 hweight32(NTF_EXT_MASK)));
1995 ndm_flags |= (ext << NTF_EXT_SHIFT);
1996 }
1997 if (ndm->ndm_ifindex) {
1998 dev = __dev_get_by_index(net, ndm->ndm_ifindex);
1999 if (dev == NULL) {
2000 err = -ENODEV;
2001 goto out;
2002 }
2003
2004 if (tb[NDA_LLADDR] && nla_len(tb[NDA_LLADDR]) < dev->addr_len) {
2005 NL_SET_ERR_MSG(extack, "Invalid link address");
2006 goto out;
2007 }
2008 }
2009
2010 tbl = neigh_find_table(ndm->ndm_family);
2011 if (tbl == NULL)
2012 return -EAFNOSUPPORT;
2013
2014 if (nla_len(tb[NDA_DST]) < (int)tbl->key_len) {
2015 NL_SET_ERR_MSG(extack, "Invalid network address");
2016 goto out;
2017 }
2018
2019 dst = nla_data(tb[NDA_DST]);
2020 lladdr = tb[NDA_LLADDR] ? nla_data(tb[NDA_LLADDR]) : NULL;
2021
2022 if (tb[NDA_PROTOCOL])
2023 protocol = nla_get_u8(tb[NDA_PROTOCOL]);
2024 if (ndm_flags & NTF_PROXY) {
2025 struct pneigh_entry *pn;
2026
2027 if (ndm_flags & NTF_MANAGED) {
2028 NL_SET_ERR_MSG(extack, "Invalid NTF_* flag combination");
2029 goto out;
2030 }
2031
2032 err = -ENOBUFS;
2033 pn = pneigh_lookup(tbl, net, dst, dev, 1);
2034 if (pn) {
2035 pn->flags = ndm_flags;
2036 if (protocol)
2037 pn->protocol = protocol;
2038 err = 0;
2039 }
2040 goto out;
2041 }
2042
2043 if (!dev) {
2044 NL_SET_ERR_MSG(extack, "Device not specified");
2045 goto out;
2046 }
2047
2048 if (tbl->allow_add && !tbl->allow_add(dev, extack)) {
2049 err = -EINVAL;
2050 goto out;
2051 }
2052
2053 neigh = neigh_lookup(tbl, dst, dev);
2054 if (neigh == NULL) {
2055 bool ndm_permanent = ndm->ndm_state & NUD_PERMANENT;
2056 bool exempt_from_gc = ndm_permanent ||
2057 ndm_flags & NTF_EXT_LEARNED;
2058
2059 if (!(nlh->nlmsg_flags & NLM_F_CREATE)) {
2060 err = -ENOENT;
2061 goto out;
2062 }
2063 if (ndm_permanent && (ndm_flags & NTF_MANAGED)) {
2064 NL_SET_ERR_MSG(extack, "Invalid NTF_* flag for permanent entry");
2065 err = -EINVAL;
2066 goto out;
2067 }
2068
2069 neigh = ___neigh_create(tbl, dst, dev,
2070 ndm_flags &
2071 (NTF_EXT_LEARNED | NTF_MANAGED),
2072 exempt_from_gc, true);
2073 if (IS_ERR(neigh)) {
2074 err = PTR_ERR(neigh);
2075 goto out;
2076 }
2077 } else {
2078 if (nlh->nlmsg_flags & NLM_F_EXCL) {
2079 err = -EEXIST;
2080 neigh_release(neigh);
2081 goto out;
2082 }
2083
2084 if (!(nlh->nlmsg_flags & NLM_F_REPLACE))
2085 flags &= ~(NEIGH_UPDATE_F_OVERRIDE |
2086 NEIGH_UPDATE_F_OVERRIDE_ISROUTER);
2087 }
2088
2089 if (protocol)
2090 neigh->protocol = protocol;
2091 if (ndm_flags & NTF_EXT_LEARNED)
2092 flags |= NEIGH_UPDATE_F_EXT_LEARNED;
2093 if (ndm_flags & NTF_ROUTER)
2094 flags |= NEIGH_UPDATE_F_ISROUTER;
2095 if (ndm_flags & NTF_MANAGED)
2096 flags |= NEIGH_UPDATE_F_MANAGED;
2097 if (ndm_flags & NTF_USE)
2098 flags |= NEIGH_UPDATE_F_USE;
2099
2100 err = __neigh_update(neigh, lladdr, ndm->ndm_state, flags,
2101 NETLINK_CB(skb).portid, extack);
2102 if (!err && ndm_flags & (NTF_USE | NTF_MANAGED)) {
2103 neigh_event_send(neigh, NULL);
2104 err = 0;
2105 }
2106 neigh_release(neigh);
2107out:
2108 return err;
2109}
2110
2111static int neightbl_fill_parms(struct sk_buff *skb, struct neigh_parms *parms)
2112{
2113 struct nlattr *nest;
2114
2115 nest = nla_nest_start_noflag(skb, NDTA_PARMS);
2116 if (nest == NULL)
2117 return -ENOBUFS;
2118
2119 if ((parms->dev &&
2120 nla_put_u32(skb, NDTPA_IFINDEX, parms->dev->ifindex)) ||
2121 nla_put_u32(skb, NDTPA_REFCNT, refcount_read(&parms->refcnt)) ||
2122 nla_put_u32(skb, NDTPA_QUEUE_LENBYTES,
2123 NEIGH_VAR(parms, QUEUE_LEN_BYTES)) ||
2124 /* approximative value for deprecated QUEUE_LEN (in packets) */
2125 nla_put_u32(skb, NDTPA_QUEUE_LEN,
2126 NEIGH_VAR(parms, QUEUE_LEN_BYTES) / SKB_TRUESIZE(ETH_FRAME_LEN)) ||
2127 nla_put_u32(skb, NDTPA_PROXY_QLEN, NEIGH_VAR(parms, PROXY_QLEN)) ||
2128 nla_put_u32(skb, NDTPA_APP_PROBES, NEIGH_VAR(parms, APP_PROBES)) ||
2129 nla_put_u32(skb, NDTPA_UCAST_PROBES,
2130 NEIGH_VAR(parms, UCAST_PROBES)) ||
2131 nla_put_u32(skb, NDTPA_MCAST_PROBES,
2132 NEIGH_VAR(parms, MCAST_PROBES)) ||
2133 nla_put_u32(skb, NDTPA_MCAST_REPROBES,
2134 NEIGH_VAR(parms, MCAST_REPROBES)) ||
2135 nla_put_msecs(skb, NDTPA_REACHABLE_TIME, parms->reachable_time,
2136 NDTPA_PAD) ||
2137 nla_put_msecs(skb, NDTPA_BASE_REACHABLE_TIME,
2138 NEIGH_VAR(parms, BASE_REACHABLE_TIME), NDTPA_PAD) ||
2139 nla_put_msecs(skb, NDTPA_GC_STALETIME,
2140 NEIGH_VAR(parms, GC_STALETIME), NDTPA_PAD) ||
2141 nla_put_msecs(skb, NDTPA_DELAY_PROBE_TIME,
2142 NEIGH_VAR(parms, DELAY_PROBE_TIME), NDTPA_PAD) ||
2143 nla_put_msecs(skb, NDTPA_RETRANS_TIME,
2144 NEIGH_VAR(parms, RETRANS_TIME), NDTPA_PAD) ||
2145 nla_put_msecs(skb, NDTPA_ANYCAST_DELAY,
2146 NEIGH_VAR(parms, ANYCAST_DELAY), NDTPA_PAD) ||
2147 nla_put_msecs(skb, NDTPA_PROXY_DELAY,
2148 NEIGH_VAR(parms, PROXY_DELAY), NDTPA_PAD) ||
2149 nla_put_msecs(skb, NDTPA_LOCKTIME,
2150 NEIGH_VAR(parms, LOCKTIME), NDTPA_PAD) ||
2151 nla_put_msecs(skb, NDTPA_INTERVAL_PROBE_TIME_MS,
2152 NEIGH_VAR(parms, INTERVAL_PROBE_TIME_MS), NDTPA_PAD))
2153 goto nla_put_failure;
2154 return nla_nest_end(skb, nest);
2155
2156nla_put_failure:
2157 nla_nest_cancel(skb, nest);
2158 return -EMSGSIZE;
2159}
2160
2161static int neightbl_fill_info(struct sk_buff *skb, struct neigh_table *tbl,
2162 u32 pid, u32 seq, int type, int flags)
2163{
2164 struct nlmsghdr *nlh;
2165 struct ndtmsg *ndtmsg;
2166
2167 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndtmsg), flags);
2168 if (nlh == NULL)
2169 return -EMSGSIZE;
2170
2171 ndtmsg = nlmsg_data(nlh);
2172
2173 read_lock_bh(&tbl->lock);
2174 ndtmsg->ndtm_family = tbl->family;
2175 ndtmsg->ndtm_pad1 = 0;
2176 ndtmsg->ndtm_pad2 = 0;
2177
2178 if (nla_put_string(skb, NDTA_NAME, tbl->id) ||
2179 nla_put_msecs(skb, NDTA_GC_INTERVAL, READ_ONCE(tbl->gc_interval),
2180 NDTA_PAD) ||
2181 nla_put_u32(skb, NDTA_THRESH1, READ_ONCE(tbl->gc_thresh1)) ||
2182 nla_put_u32(skb, NDTA_THRESH2, READ_ONCE(tbl->gc_thresh2)) ||
2183 nla_put_u32(skb, NDTA_THRESH3, READ_ONCE(tbl->gc_thresh3)))
2184 goto nla_put_failure;
2185 {
2186 unsigned long now = jiffies;
2187 long flush_delta = now - READ_ONCE(tbl->last_flush);
2188 long rand_delta = now - READ_ONCE(tbl->last_rand);
2189 struct neigh_hash_table *nht;
2190 struct ndt_config ndc = {
2191 .ndtc_key_len = tbl->key_len,
2192 .ndtc_entry_size = tbl->entry_size,
2193 .ndtc_entries = atomic_read(&tbl->entries),
2194 .ndtc_last_flush = jiffies_to_msecs(flush_delta),
2195 .ndtc_last_rand = jiffies_to_msecs(rand_delta),
2196 .ndtc_proxy_qlen = READ_ONCE(tbl->proxy_queue.qlen),
2197 };
2198
2199 rcu_read_lock();
2200 nht = rcu_dereference(tbl->nht);
2201 ndc.ndtc_hash_rnd = nht->hash_rnd[0];
2202 ndc.ndtc_hash_mask = ((1 << nht->hash_shift) - 1);
2203 rcu_read_unlock();
2204
2205 if (nla_put(skb, NDTA_CONFIG, sizeof(ndc), &ndc))
2206 goto nla_put_failure;
2207 }
2208
2209 {
2210 int cpu;
2211 struct ndt_stats ndst;
2212
2213 memset(&ndst, 0, sizeof(ndst));
2214
2215 for_each_possible_cpu(cpu) {
2216 struct neigh_statistics *st;
2217
2218 st = per_cpu_ptr(tbl->stats, cpu);
2219 ndst.ndts_allocs += READ_ONCE(st->allocs);
2220 ndst.ndts_destroys += READ_ONCE(st->destroys);
2221 ndst.ndts_hash_grows += READ_ONCE(st->hash_grows);
2222 ndst.ndts_res_failed += READ_ONCE(st->res_failed);
2223 ndst.ndts_lookups += READ_ONCE(st->lookups);
2224 ndst.ndts_hits += READ_ONCE(st->hits);
2225 ndst.ndts_rcv_probes_mcast += READ_ONCE(st->rcv_probes_mcast);
2226 ndst.ndts_rcv_probes_ucast += READ_ONCE(st->rcv_probes_ucast);
2227 ndst.ndts_periodic_gc_runs += READ_ONCE(st->periodic_gc_runs);
2228 ndst.ndts_forced_gc_runs += READ_ONCE(st->forced_gc_runs);
2229 ndst.ndts_table_fulls += READ_ONCE(st->table_fulls);
2230 }
2231
2232 if (nla_put_64bit(skb, NDTA_STATS, sizeof(ndst), &ndst,
2233 NDTA_PAD))
2234 goto nla_put_failure;
2235 }
2236
2237 BUG_ON(tbl->parms.dev);
2238 if (neightbl_fill_parms(skb, &tbl->parms) < 0)
2239 goto nla_put_failure;
2240
2241 read_unlock_bh(&tbl->lock);
2242 nlmsg_end(skb, nlh);
2243 return 0;
2244
2245nla_put_failure:
2246 read_unlock_bh(&tbl->lock);
2247 nlmsg_cancel(skb, nlh);
2248 return -EMSGSIZE;
2249}
2250
2251static int neightbl_fill_param_info(struct sk_buff *skb,
2252 struct neigh_table *tbl,
2253 struct neigh_parms *parms,
2254 u32 pid, u32 seq, int type,
2255 unsigned int flags)
2256{
2257 struct ndtmsg *ndtmsg;
2258 struct nlmsghdr *nlh;
2259
2260 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndtmsg), flags);
2261 if (nlh == NULL)
2262 return -EMSGSIZE;
2263
2264 ndtmsg = nlmsg_data(nlh);
2265
2266 read_lock_bh(&tbl->lock);
2267 ndtmsg->ndtm_family = tbl->family;
2268 ndtmsg->ndtm_pad1 = 0;
2269 ndtmsg->ndtm_pad2 = 0;
2270
2271 if (nla_put_string(skb, NDTA_NAME, tbl->id) < 0 ||
2272 neightbl_fill_parms(skb, parms) < 0)
2273 goto errout;
2274
2275 read_unlock_bh(&tbl->lock);
2276 nlmsg_end(skb, nlh);
2277 return 0;
2278errout:
2279 read_unlock_bh(&tbl->lock);
2280 nlmsg_cancel(skb, nlh);
2281 return -EMSGSIZE;
2282}
2283
2284static const struct nla_policy nl_neightbl_policy[NDTA_MAX+1] = {
2285 [NDTA_NAME] = { .type = NLA_STRING },
2286 [NDTA_THRESH1] = { .type = NLA_U32 },
2287 [NDTA_THRESH2] = { .type = NLA_U32 },
2288 [NDTA_THRESH3] = { .type = NLA_U32 },
2289 [NDTA_GC_INTERVAL] = { .type = NLA_U64 },
2290 [NDTA_PARMS] = { .type = NLA_NESTED },
2291};
2292
2293static const struct nla_policy nl_ntbl_parm_policy[NDTPA_MAX+1] = {
2294 [NDTPA_IFINDEX] = { .type = NLA_U32 },
2295 [NDTPA_QUEUE_LEN] = { .type = NLA_U32 },
2296 [NDTPA_PROXY_QLEN] = { .type = NLA_U32 },
2297 [NDTPA_APP_PROBES] = { .type = NLA_U32 },
2298 [NDTPA_UCAST_PROBES] = { .type = NLA_U32 },
2299 [NDTPA_MCAST_PROBES] = { .type = NLA_U32 },
2300 [NDTPA_MCAST_REPROBES] = { .type = NLA_U32 },
2301 [NDTPA_BASE_REACHABLE_TIME] = { .type = NLA_U64 },
2302 [NDTPA_GC_STALETIME] = { .type = NLA_U64 },
2303 [NDTPA_DELAY_PROBE_TIME] = { .type = NLA_U64 },
2304 [NDTPA_RETRANS_TIME] = { .type = NLA_U64 },
2305 [NDTPA_ANYCAST_DELAY] = { .type = NLA_U64 },
2306 [NDTPA_PROXY_DELAY] = { .type = NLA_U64 },
2307 [NDTPA_LOCKTIME] = { .type = NLA_U64 },
2308 [NDTPA_INTERVAL_PROBE_TIME_MS] = { .type = NLA_U64, .min = 1 },
2309};
2310
2311static int neightbl_set(struct sk_buff *skb, struct nlmsghdr *nlh,
2312 struct netlink_ext_ack *extack)
2313{
2314 struct net *net = sock_net(skb->sk);
2315 struct neigh_table *tbl;
2316 struct ndtmsg *ndtmsg;
2317 struct nlattr *tb[NDTA_MAX+1];
2318 bool found = false;
2319 int err, tidx;
2320
2321 err = nlmsg_parse_deprecated(nlh, sizeof(*ndtmsg), tb, NDTA_MAX,
2322 nl_neightbl_policy, extack);
2323 if (err < 0)
2324 goto errout;
2325
2326 if (tb[NDTA_NAME] == NULL) {
2327 err = -EINVAL;
2328 goto errout;
2329 }
2330
2331 ndtmsg = nlmsg_data(nlh);
2332
2333 for (tidx = 0; tidx < NEIGH_NR_TABLES; tidx++) {
2334 tbl = neigh_tables[tidx];
2335 if (!tbl)
2336 continue;
2337 if (ndtmsg->ndtm_family && tbl->family != ndtmsg->ndtm_family)
2338 continue;
2339 if (nla_strcmp(tb[NDTA_NAME], tbl->id) == 0) {
2340 found = true;
2341 break;
2342 }
2343 }
2344
2345 if (!found)
2346 return -ENOENT;
2347
2348 /*
2349 * We acquire tbl->lock to be nice to the periodic timers and
2350 * make sure they always see a consistent set of values.
2351 */
2352 write_lock_bh(&tbl->lock);
2353
2354 if (tb[NDTA_PARMS]) {
2355 struct nlattr *tbp[NDTPA_MAX+1];
2356 struct neigh_parms *p;
2357 int i, ifindex = 0;
2358
2359 err = nla_parse_nested_deprecated(tbp, NDTPA_MAX,
2360 tb[NDTA_PARMS],
2361 nl_ntbl_parm_policy, extack);
2362 if (err < 0)
2363 goto errout_tbl_lock;
2364
2365 if (tbp[NDTPA_IFINDEX])
2366 ifindex = nla_get_u32(tbp[NDTPA_IFINDEX]);
2367
2368 p = lookup_neigh_parms(tbl, net, ifindex);
2369 if (p == NULL) {
2370 err = -ENOENT;
2371 goto errout_tbl_lock;
2372 }
2373
2374 for (i = 1; i <= NDTPA_MAX; i++) {
2375 if (tbp[i] == NULL)
2376 continue;
2377
2378 switch (i) {
2379 case NDTPA_QUEUE_LEN:
2380 NEIGH_VAR_SET(p, QUEUE_LEN_BYTES,
2381 nla_get_u32(tbp[i]) *
2382 SKB_TRUESIZE(ETH_FRAME_LEN));
2383 break;
2384 case NDTPA_QUEUE_LENBYTES:
2385 NEIGH_VAR_SET(p, QUEUE_LEN_BYTES,
2386 nla_get_u32(tbp[i]));
2387 break;
2388 case NDTPA_PROXY_QLEN:
2389 NEIGH_VAR_SET(p, PROXY_QLEN,
2390 nla_get_u32(tbp[i]));
2391 break;
2392 case NDTPA_APP_PROBES:
2393 NEIGH_VAR_SET(p, APP_PROBES,
2394 nla_get_u32(tbp[i]));
2395 break;
2396 case NDTPA_UCAST_PROBES:
2397 NEIGH_VAR_SET(p, UCAST_PROBES,
2398 nla_get_u32(tbp[i]));
2399 break;
2400 case NDTPA_MCAST_PROBES:
2401 NEIGH_VAR_SET(p, MCAST_PROBES,
2402 nla_get_u32(tbp[i]));
2403 break;
2404 case NDTPA_MCAST_REPROBES:
2405 NEIGH_VAR_SET(p, MCAST_REPROBES,
2406 nla_get_u32(tbp[i]));
2407 break;
2408 case NDTPA_BASE_REACHABLE_TIME:
2409 NEIGH_VAR_SET(p, BASE_REACHABLE_TIME,
2410 nla_get_msecs(tbp[i]));
2411 /* update reachable_time as well, otherwise, the change will
2412 * only be effective after the next time neigh_periodic_work
2413 * decides to recompute it (can be multiple minutes)
2414 */
2415 p->reachable_time =
2416 neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME));
2417 break;
2418 case NDTPA_GC_STALETIME:
2419 NEIGH_VAR_SET(p, GC_STALETIME,
2420 nla_get_msecs(tbp[i]));
2421 break;
2422 case NDTPA_DELAY_PROBE_TIME:
2423 NEIGH_VAR_SET(p, DELAY_PROBE_TIME,
2424 nla_get_msecs(tbp[i]));
2425 call_netevent_notifiers(NETEVENT_DELAY_PROBE_TIME_UPDATE, p);
2426 break;
2427 case NDTPA_INTERVAL_PROBE_TIME_MS:
2428 NEIGH_VAR_SET(p, INTERVAL_PROBE_TIME_MS,
2429 nla_get_msecs(tbp[i]));
2430 break;
2431 case NDTPA_RETRANS_TIME:
2432 NEIGH_VAR_SET(p, RETRANS_TIME,
2433 nla_get_msecs(tbp[i]));
2434 break;
2435 case NDTPA_ANYCAST_DELAY:
2436 NEIGH_VAR_SET(p, ANYCAST_DELAY,
2437 nla_get_msecs(tbp[i]));
2438 break;
2439 case NDTPA_PROXY_DELAY:
2440 NEIGH_VAR_SET(p, PROXY_DELAY,
2441 nla_get_msecs(tbp[i]));
2442 break;
2443 case NDTPA_LOCKTIME:
2444 NEIGH_VAR_SET(p, LOCKTIME,
2445 nla_get_msecs(tbp[i]));
2446 break;
2447 }
2448 }
2449 }
2450
2451 err = -ENOENT;
2452 if ((tb[NDTA_THRESH1] || tb[NDTA_THRESH2] ||
2453 tb[NDTA_THRESH3] || tb[NDTA_GC_INTERVAL]) &&
2454 !net_eq(net, &init_net))
2455 goto errout_tbl_lock;
2456
2457 if (tb[NDTA_THRESH1])
2458 WRITE_ONCE(tbl->gc_thresh1, nla_get_u32(tb[NDTA_THRESH1]));
2459
2460 if (tb[NDTA_THRESH2])
2461 WRITE_ONCE(tbl->gc_thresh2, nla_get_u32(tb[NDTA_THRESH2]));
2462
2463 if (tb[NDTA_THRESH3])
2464 WRITE_ONCE(tbl->gc_thresh3, nla_get_u32(tb[NDTA_THRESH3]));
2465
2466 if (tb[NDTA_GC_INTERVAL])
2467 WRITE_ONCE(tbl->gc_interval, nla_get_msecs(tb[NDTA_GC_INTERVAL]));
2468
2469 err = 0;
2470
2471errout_tbl_lock:
2472 write_unlock_bh(&tbl->lock);
2473errout:
2474 return err;
2475}
2476
2477static int neightbl_valid_dump_info(const struct nlmsghdr *nlh,
2478 struct netlink_ext_ack *extack)
2479{
2480 struct ndtmsg *ndtm;
2481
2482 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ndtm))) {
2483 NL_SET_ERR_MSG(extack, "Invalid header for neighbor table dump request");
2484 return -EINVAL;
2485 }
2486
2487 ndtm = nlmsg_data(nlh);
2488 if (ndtm->ndtm_pad1 || ndtm->ndtm_pad2) {
2489 NL_SET_ERR_MSG(extack, "Invalid values in header for neighbor table dump request");
2490 return -EINVAL;
2491 }
2492
2493 if (nlmsg_attrlen(nlh, sizeof(*ndtm))) {
2494 NL_SET_ERR_MSG(extack, "Invalid data after header in neighbor table dump request");
2495 return -EINVAL;
2496 }
2497
2498 return 0;
2499}
2500
2501static int neightbl_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
2502{
2503 const struct nlmsghdr *nlh = cb->nlh;
2504 struct net *net = sock_net(skb->sk);
2505 int family, tidx, nidx = 0;
2506 int tbl_skip = cb->args[0];
2507 int neigh_skip = cb->args[1];
2508 struct neigh_table *tbl;
2509
2510 if (cb->strict_check) {
2511 int err = neightbl_valid_dump_info(nlh, cb->extack);
2512
2513 if (err < 0)
2514 return err;
2515 }
2516
2517 family = ((struct rtgenmsg *)nlmsg_data(nlh))->rtgen_family;
2518
2519 for (tidx = 0; tidx < NEIGH_NR_TABLES; tidx++) {
2520 struct neigh_parms *p;
2521
2522 tbl = neigh_tables[tidx];
2523 if (!tbl)
2524 continue;
2525
2526 if (tidx < tbl_skip || (family && tbl->family != family))
2527 continue;
2528
2529 if (neightbl_fill_info(skb, tbl, NETLINK_CB(cb->skb).portid,
2530 nlh->nlmsg_seq, RTM_NEWNEIGHTBL,
2531 NLM_F_MULTI) < 0)
2532 break;
2533
2534 nidx = 0;
2535 p = list_next_entry(&tbl->parms, list);
2536 list_for_each_entry_from(p, &tbl->parms_list, list) {
2537 if (!net_eq(neigh_parms_net(p), net))
2538 continue;
2539
2540 if (nidx < neigh_skip)
2541 goto next;
2542
2543 if (neightbl_fill_param_info(skb, tbl, p,
2544 NETLINK_CB(cb->skb).portid,
2545 nlh->nlmsg_seq,
2546 RTM_NEWNEIGHTBL,
2547 NLM_F_MULTI) < 0)
2548 goto out;
2549 next:
2550 nidx++;
2551 }
2552
2553 neigh_skip = 0;
2554 }
2555out:
2556 cb->args[0] = tidx;
2557 cb->args[1] = nidx;
2558
2559 return skb->len;
2560}
2561
2562static int neigh_fill_info(struct sk_buff *skb, struct neighbour *neigh,
2563 u32 pid, u32 seq, int type, unsigned int flags)
2564{
2565 u32 neigh_flags, neigh_flags_ext;
2566 unsigned long now = jiffies;
2567 struct nda_cacheinfo ci;
2568 struct nlmsghdr *nlh;
2569 struct ndmsg *ndm;
2570
2571 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndm), flags);
2572 if (nlh == NULL)
2573 return -EMSGSIZE;
2574
2575 neigh_flags_ext = neigh->flags >> NTF_EXT_SHIFT;
2576 neigh_flags = neigh->flags & NTF_OLD_MASK;
2577
2578 ndm = nlmsg_data(nlh);
2579 ndm->ndm_family = neigh->ops->family;
2580 ndm->ndm_pad1 = 0;
2581 ndm->ndm_pad2 = 0;
2582 ndm->ndm_flags = neigh_flags;
2583 ndm->ndm_type = neigh->type;
2584 ndm->ndm_ifindex = neigh->dev->ifindex;
2585
2586 if (nla_put(skb, NDA_DST, neigh->tbl->key_len, neigh->primary_key))
2587 goto nla_put_failure;
2588
2589 read_lock_bh(&neigh->lock);
2590 ndm->ndm_state = neigh->nud_state;
2591 if (neigh->nud_state & NUD_VALID) {
2592 char haddr[MAX_ADDR_LEN];
2593
2594 neigh_ha_snapshot(haddr, neigh, neigh->dev);
2595 if (nla_put(skb, NDA_LLADDR, neigh->dev->addr_len, haddr) < 0) {
2596 read_unlock_bh(&neigh->lock);
2597 goto nla_put_failure;
2598 }
2599 }
2600
2601 ci.ndm_used = jiffies_to_clock_t(now - neigh->used);
2602 ci.ndm_confirmed = jiffies_to_clock_t(now - neigh->confirmed);
2603 ci.ndm_updated = jiffies_to_clock_t(now - neigh->updated);
2604 ci.ndm_refcnt = refcount_read(&neigh->refcnt) - 1;
2605 read_unlock_bh(&neigh->lock);
2606
2607 if (nla_put_u32(skb, NDA_PROBES, atomic_read(&neigh->probes)) ||
2608 nla_put(skb, NDA_CACHEINFO, sizeof(ci), &ci))
2609 goto nla_put_failure;
2610
2611 if (neigh->protocol && nla_put_u8(skb, NDA_PROTOCOL, neigh->protocol))
2612 goto nla_put_failure;
2613 if (neigh_flags_ext && nla_put_u32(skb, NDA_FLAGS_EXT, neigh_flags_ext))
2614 goto nla_put_failure;
2615
2616 nlmsg_end(skb, nlh);
2617 return 0;
2618
2619nla_put_failure:
2620 nlmsg_cancel(skb, nlh);
2621 return -EMSGSIZE;
2622}
2623
2624static int pneigh_fill_info(struct sk_buff *skb, struct pneigh_entry *pn,
2625 u32 pid, u32 seq, int type, unsigned int flags,
2626 struct neigh_table *tbl)
2627{
2628 u32 neigh_flags, neigh_flags_ext;
2629 struct nlmsghdr *nlh;
2630 struct ndmsg *ndm;
2631
2632 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndm), flags);
2633 if (nlh == NULL)
2634 return -EMSGSIZE;
2635
2636 neigh_flags_ext = pn->flags >> NTF_EXT_SHIFT;
2637 neigh_flags = pn->flags & NTF_OLD_MASK;
2638
2639 ndm = nlmsg_data(nlh);
2640 ndm->ndm_family = tbl->family;
2641 ndm->ndm_pad1 = 0;
2642 ndm->ndm_pad2 = 0;
2643 ndm->ndm_flags = neigh_flags | NTF_PROXY;
2644 ndm->ndm_type = RTN_UNICAST;
2645 ndm->ndm_ifindex = pn->dev ? pn->dev->ifindex : 0;
2646 ndm->ndm_state = NUD_NONE;
2647
2648 if (nla_put(skb, NDA_DST, tbl->key_len, pn->key))
2649 goto nla_put_failure;
2650
2651 if (pn->protocol && nla_put_u8(skb, NDA_PROTOCOL, pn->protocol))
2652 goto nla_put_failure;
2653 if (neigh_flags_ext && nla_put_u32(skb, NDA_FLAGS_EXT, neigh_flags_ext))
2654 goto nla_put_failure;
2655
2656 nlmsg_end(skb, nlh);
2657 return 0;
2658
2659nla_put_failure:
2660 nlmsg_cancel(skb, nlh);
2661 return -EMSGSIZE;
2662}
2663
2664static void neigh_update_notify(struct neighbour *neigh, u32 nlmsg_pid)
2665{
2666 call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, neigh);
2667 __neigh_notify(neigh, RTM_NEWNEIGH, 0, nlmsg_pid);
2668}
2669
2670static bool neigh_master_filtered(struct net_device *dev, int master_idx)
2671{
2672 struct net_device *master;
2673
2674 if (!master_idx)
2675 return false;
2676
2677 master = dev ? netdev_master_upper_dev_get(dev) : NULL;
2678
2679 /* 0 is already used to denote NDA_MASTER wasn't passed, therefore need another
2680 * invalid value for ifindex to denote "no master".
2681 */
2682 if (master_idx == -1)
2683 return !!master;
2684
2685 if (!master || master->ifindex != master_idx)
2686 return true;
2687
2688 return false;
2689}
2690
2691static bool neigh_ifindex_filtered(struct net_device *dev, int filter_idx)
2692{
2693 if (filter_idx && (!dev || dev->ifindex != filter_idx))
2694 return true;
2695
2696 return false;
2697}
2698
2699struct neigh_dump_filter {
2700 int master_idx;
2701 int dev_idx;
2702};
2703
2704static int neigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb,
2705 struct netlink_callback *cb,
2706 struct neigh_dump_filter *filter)
2707{
2708 struct net *net = sock_net(skb->sk);
2709 struct neighbour *n;
2710 int rc, h, s_h = cb->args[1];
2711 int idx, s_idx = idx = cb->args[2];
2712 struct neigh_hash_table *nht;
2713 unsigned int flags = NLM_F_MULTI;
2714
2715 if (filter->dev_idx || filter->master_idx)
2716 flags |= NLM_F_DUMP_FILTERED;
2717
2718 rcu_read_lock();
2719 nht = rcu_dereference(tbl->nht);
2720
2721 for (h = s_h; h < (1 << nht->hash_shift); h++) {
2722 if (h > s_h)
2723 s_idx = 0;
2724 for (n = rcu_dereference(nht->hash_buckets[h]), idx = 0;
2725 n != NULL;
2726 n = rcu_dereference(n->next)) {
2727 if (idx < s_idx || !net_eq(dev_net(n->dev), net))
2728 goto next;
2729 if (neigh_ifindex_filtered(n->dev, filter->dev_idx) ||
2730 neigh_master_filtered(n->dev, filter->master_idx))
2731 goto next;
2732 if (neigh_fill_info(skb, n, NETLINK_CB(cb->skb).portid,
2733 cb->nlh->nlmsg_seq,
2734 RTM_NEWNEIGH,
2735 flags) < 0) {
2736 rc = -1;
2737 goto out;
2738 }
2739next:
2740 idx++;
2741 }
2742 }
2743 rc = skb->len;
2744out:
2745 rcu_read_unlock();
2746 cb->args[1] = h;
2747 cb->args[2] = idx;
2748 return rc;
2749}
2750
2751static int pneigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb,
2752 struct netlink_callback *cb,
2753 struct neigh_dump_filter *filter)
2754{
2755 struct pneigh_entry *n;
2756 struct net *net = sock_net(skb->sk);
2757 int rc, h, s_h = cb->args[3];
2758 int idx, s_idx = idx = cb->args[4];
2759 unsigned int flags = NLM_F_MULTI;
2760
2761 if (filter->dev_idx || filter->master_idx)
2762 flags |= NLM_F_DUMP_FILTERED;
2763
2764 read_lock_bh(&tbl->lock);
2765
2766 for (h = s_h; h <= PNEIGH_HASHMASK; h++) {
2767 if (h > s_h)
2768 s_idx = 0;
2769 for (n = tbl->phash_buckets[h], idx = 0; n; n = n->next) {
2770 if (idx < s_idx || pneigh_net(n) != net)
2771 goto next;
2772 if (neigh_ifindex_filtered(n->dev, filter->dev_idx) ||
2773 neigh_master_filtered(n->dev, filter->master_idx))
2774 goto next;
2775 if (pneigh_fill_info(skb, n, NETLINK_CB(cb->skb).portid,
2776 cb->nlh->nlmsg_seq,
2777 RTM_NEWNEIGH, flags, tbl) < 0) {
2778 read_unlock_bh(&tbl->lock);
2779 rc = -1;
2780 goto out;
2781 }
2782 next:
2783 idx++;
2784 }
2785 }
2786
2787 read_unlock_bh(&tbl->lock);
2788 rc = skb->len;
2789out:
2790 cb->args[3] = h;
2791 cb->args[4] = idx;
2792 return rc;
2793
2794}
2795
2796static int neigh_valid_dump_req(const struct nlmsghdr *nlh,
2797 bool strict_check,
2798 struct neigh_dump_filter *filter,
2799 struct netlink_ext_ack *extack)
2800{
2801 struct nlattr *tb[NDA_MAX + 1];
2802 int err, i;
2803
2804 if (strict_check) {
2805 struct ndmsg *ndm;
2806
2807 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ndm))) {
2808 NL_SET_ERR_MSG(extack, "Invalid header for neighbor dump request");
2809 return -EINVAL;
2810 }
2811
2812 ndm = nlmsg_data(nlh);
2813 if (ndm->ndm_pad1 || ndm->ndm_pad2 || ndm->ndm_ifindex ||
2814 ndm->ndm_state || ndm->ndm_type) {
2815 NL_SET_ERR_MSG(extack, "Invalid values in header for neighbor dump request");
2816 return -EINVAL;
2817 }
2818
2819 if (ndm->ndm_flags & ~NTF_PROXY) {
2820 NL_SET_ERR_MSG(extack, "Invalid flags in header for neighbor dump request");
2821 return -EINVAL;
2822 }
2823
2824 err = nlmsg_parse_deprecated_strict(nlh, sizeof(struct ndmsg),
2825 tb, NDA_MAX, nda_policy,
2826 extack);
2827 } else {
2828 err = nlmsg_parse_deprecated(nlh, sizeof(struct ndmsg), tb,
2829 NDA_MAX, nda_policy, extack);
2830 }
2831 if (err < 0)
2832 return err;
2833
2834 for (i = 0; i <= NDA_MAX; ++i) {
2835 if (!tb[i])
2836 continue;
2837
2838 /* all new attributes should require strict_check */
2839 switch (i) {
2840 case NDA_IFINDEX:
2841 filter->dev_idx = nla_get_u32(tb[i]);
2842 break;
2843 case NDA_MASTER:
2844 filter->master_idx = nla_get_u32(tb[i]);
2845 break;
2846 default:
2847 if (strict_check) {
2848 NL_SET_ERR_MSG(extack, "Unsupported attribute in neighbor dump request");
2849 return -EINVAL;
2850 }
2851 }
2852 }
2853
2854 return 0;
2855}
2856
2857static int neigh_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
2858{
2859 const struct nlmsghdr *nlh = cb->nlh;
2860 struct neigh_dump_filter filter = {};
2861 struct neigh_table *tbl;
2862 int t, family, s_t;
2863 int proxy = 0;
2864 int err;
2865
2866 family = ((struct rtgenmsg *)nlmsg_data(nlh))->rtgen_family;
2867
2868 /* check for full ndmsg structure presence, family member is
2869 * the same for both structures
2870 */
2871 if (nlmsg_len(nlh) >= sizeof(struct ndmsg) &&
2872 ((struct ndmsg *)nlmsg_data(nlh))->ndm_flags == NTF_PROXY)
2873 proxy = 1;
2874
2875 err = neigh_valid_dump_req(nlh, cb->strict_check, &filter, cb->extack);
2876 if (err < 0 && cb->strict_check)
2877 return err;
2878
2879 s_t = cb->args[0];
2880
2881 for (t = 0; t < NEIGH_NR_TABLES; t++) {
2882 tbl = neigh_tables[t];
2883
2884 if (!tbl)
2885 continue;
2886 if (t < s_t || (family && tbl->family != family))
2887 continue;
2888 if (t > s_t)
2889 memset(&cb->args[1], 0, sizeof(cb->args) -
2890 sizeof(cb->args[0]));
2891 if (proxy)
2892 err = pneigh_dump_table(tbl, skb, cb, &filter);
2893 else
2894 err = neigh_dump_table(tbl, skb, cb, &filter);
2895 if (err < 0)
2896 break;
2897 }
2898
2899 cb->args[0] = t;
2900 return skb->len;
2901}
2902
2903static int neigh_valid_get_req(const struct nlmsghdr *nlh,
2904 struct neigh_table **tbl,
2905 void **dst, int *dev_idx, u8 *ndm_flags,
2906 struct netlink_ext_ack *extack)
2907{
2908 struct nlattr *tb[NDA_MAX + 1];
2909 struct ndmsg *ndm;
2910 int err, i;
2911
2912 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ndm))) {
2913 NL_SET_ERR_MSG(extack, "Invalid header for neighbor get request");
2914 return -EINVAL;
2915 }
2916
2917 ndm = nlmsg_data(nlh);
2918 if (ndm->ndm_pad1 || ndm->ndm_pad2 || ndm->ndm_state ||
2919 ndm->ndm_type) {
2920 NL_SET_ERR_MSG(extack, "Invalid values in header for neighbor get request");
2921 return -EINVAL;
2922 }
2923
2924 if (ndm->ndm_flags & ~NTF_PROXY) {
2925 NL_SET_ERR_MSG(extack, "Invalid flags in header for neighbor get request");
2926 return -EINVAL;
2927 }
2928
2929 err = nlmsg_parse_deprecated_strict(nlh, sizeof(struct ndmsg), tb,
2930 NDA_MAX, nda_policy, extack);
2931 if (err < 0)
2932 return err;
2933
2934 *ndm_flags = ndm->ndm_flags;
2935 *dev_idx = ndm->ndm_ifindex;
2936 *tbl = neigh_find_table(ndm->ndm_family);
2937 if (*tbl == NULL) {
2938 NL_SET_ERR_MSG(extack, "Unsupported family in header for neighbor get request");
2939 return -EAFNOSUPPORT;
2940 }
2941
2942 for (i = 0; i <= NDA_MAX; ++i) {
2943 if (!tb[i])
2944 continue;
2945
2946 switch (i) {
2947 case NDA_DST:
2948 if (nla_len(tb[i]) != (int)(*tbl)->key_len) {
2949 NL_SET_ERR_MSG(extack, "Invalid network address in neighbor get request");
2950 return -EINVAL;
2951 }
2952 *dst = nla_data(tb[i]);
2953 break;
2954 default:
2955 NL_SET_ERR_MSG(extack, "Unsupported attribute in neighbor get request");
2956 return -EINVAL;
2957 }
2958 }
2959
2960 return 0;
2961}
2962
2963static inline size_t neigh_nlmsg_size(void)
2964{
2965 return NLMSG_ALIGN(sizeof(struct ndmsg))
2966 + nla_total_size(MAX_ADDR_LEN) /* NDA_DST */
2967 + nla_total_size(MAX_ADDR_LEN) /* NDA_LLADDR */
2968 + nla_total_size(sizeof(struct nda_cacheinfo))
2969 + nla_total_size(4) /* NDA_PROBES */
2970 + nla_total_size(4) /* NDA_FLAGS_EXT */
2971 + nla_total_size(1); /* NDA_PROTOCOL */
2972}
2973
2974static int neigh_get_reply(struct net *net, struct neighbour *neigh,
2975 u32 pid, u32 seq)
2976{
2977 struct sk_buff *skb;
2978 int err = 0;
2979
2980 skb = nlmsg_new(neigh_nlmsg_size(), GFP_KERNEL);
2981 if (!skb)
2982 return -ENOBUFS;
2983
2984 err = neigh_fill_info(skb, neigh, pid, seq, RTM_NEWNEIGH, 0);
2985 if (err) {
2986 kfree_skb(skb);
2987 goto errout;
2988 }
2989
2990 err = rtnl_unicast(skb, net, pid);
2991errout:
2992 return err;
2993}
2994
2995static inline size_t pneigh_nlmsg_size(void)
2996{
2997 return NLMSG_ALIGN(sizeof(struct ndmsg))
2998 + nla_total_size(MAX_ADDR_LEN) /* NDA_DST */
2999 + nla_total_size(4) /* NDA_FLAGS_EXT */
3000 + nla_total_size(1); /* NDA_PROTOCOL */
3001}
3002
3003static int pneigh_get_reply(struct net *net, struct pneigh_entry *neigh,
3004 u32 pid, u32 seq, struct neigh_table *tbl)
3005{
3006 struct sk_buff *skb;
3007 int err = 0;
3008
3009 skb = nlmsg_new(pneigh_nlmsg_size(), GFP_KERNEL);
3010 if (!skb)
3011 return -ENOBUFS;
3012
3013 err = pneigh_fill_info(skb, neigh, pid, seq, RTM_NEWNEIGH, 0, tbl);
3014 if (err) {
3015 kfree_skb(skb);
3016 goto errout;
3017 }
3018
3019 err = rtnl_unicast(skb, net, pid);
3020errout:
3021 return err;
3022}
3023
3024static int neigh_get(struct sk_buff *in_skb, struct nlmsghdr *nlh,
3025 struct netlink_ext_ack *extack)
3026{
3027 struct net *net = sock_net(in_skb->sk);
3028 struct net_device *dev = NULL;
3029 struct neigh_table *tbl = NULL;
3030 struct neighbour *neigh;
3031 void *dst = NULL;
3032 u8 ndm_flags = 0;
3033 int dev_idx = 0;
3034 int err;
3035
3036 err = neigh_valid_get_req(nlh, &tbl, &dst, &dev_idx, &ndm_flags,
3037 extack);
3038 if (err < 0)
3039 return err;
3040
3041 if (dev_idx) {
3042 dev = __dev_get_by_index(net, dev_idx);
3043 if (!dev) {
3044 NL_SET_ERR_MSG(extack, "Unknown device ifindex");
3045 return -ENODEV;
3046 }
3047 }
3048
3049 if (!dst) {
3050 NL_SET_ERR_MSG(extack, "Network address not specified");
3051 return -EINVAL;
3052 }
3053
3054 if (ndm_flags & NTF_PROXY) {
3055 struct pneigh_entry *pn;
3056
3057 pn = pneigh_lookup(tbl, net, dst, dev, 0);
3058 if (!pn) {
3059 NL_SET_ERR_MSG(extack, "Proxy neighbour entry not found");
3060 return -ENOENT;
3061 }
3062 return pneigh_get_reply(net, pn, NETLINK_CB(in_skb).portid,
3063 nlh->nlmsg_seq, tbl);
3064 }
3065
3066 if (!dev) {
3067 NL_SET_ERR_MSG(extack, "No device specified");
3068 return -EINVAL;
3069 }
3070
3071 neigh = neigh_lookup(tbl, dst, dev);
3072 if (!neigh) {
3073 NL_SET_ERR_MSG(extack, "Neighbour entry not found");
3074 return -ENOENT;
3075 }
3076
3077 err = neigh_get_reply(net, neigh, NETLINK_CB(in_skb).portid,
3078 nlh->nlmsg_seq);
3079
3080 neigh_release(neigh);
3081
3082 return err;
3083}
3084
3085void neigh_for_each(struct neigh_table *tbl, void (*cb)(struct neighbour *, void *), void *cookie)
3086{
3087 int chain;
3088 struct neigh_hash_table *nht;
3089
3090 rcu_read_lock();
3091 nht = rcu_dereference(tbl->nht);
3092
3093 read_lock_bh(&tbl->lock); /* avoid resizes */
3094 for (chain = 0; chain < (1 << nht->hash_shift); chain++) {
3095 struct neighbour *n;
3096
3097 for (n = rcu_dereference(nht->hash_buckets[chain]);
3098 n != NULL;
3099 n = rcu_dereference(n->next))
3100 cb(n, cookie);
3101 }
3102 read_unlock_bh(&tbl->lock);
3103 rcu_read_unlock();
3104}
3105EXPORT_SYMBOL(neigh_for_each);
3106
3107/* The tbl->lock must be held as a writer and BH disabled. */
3108void __neigh_for_each_release(struct neigh_table *tbl,
3109 int (*cb)(struct neighbour *))
3110{
3111 int chain;
3112 struct neigh_hash_table *nht;
3113
3114 nht = rcu_dereference_protected(tbl->nht,
3115 lockdep_is_held(&tbl->lock));
3116 for (chain = 0; chain < (1 << nht->hash_shift); chain++) {
3117 struct neighbour *n;
3118 struct neighbour __rcu **np;
3119
3120 np = &nht->hash_buckets[chain];
3121 while ((n = rcu_dereference_protected(*np,
3122 lockdep_is_held(&tbl->lock))) != NULL) {
3123 int release;
3124
3125 write_lock(&n->lock);
3126 release = cb(n);
3127 if (release) {
3128 rcu_assign_pointer(*np,
3129 rcu_dereference_protected(n->next,
3130 lockdep_is_held(&tbl->lock)));
3131 neigh_mark_dead(n);
3132 } else
3133 np = &n->next;
3134 write_unlock(&n->lock);
3135 if (release)
3136 neigh_cleanup_and_release(n);
3137 }
3138 }
3139}
3140EXPORT_SYMBOL(__neigh_for_each_release);
3141
3142int neigh_xmit(int index, struct net_device *dev,
3143 const void *addr, struct sk_buff *skb)
3144{
3145 int err = -EAFNOSUPPORT;
3146 if (likely(index < NEIGH_NR_TABLES)) {
3147 struct neigh_table *tbl;
3148 struct neighbour *neigh;
3149
3150 tbl = neigh_tables[index];
3151 if (!tbl)
3152 goto out;
3153 rcu_read_lock();
3154 if (index == NEIGH_ARP_TABLE) {
3155 u32 key = *((u32 *)addr);
3156
3157 neigh = __ipv4_neigh_lookup_noref(dev, key);
3158 } else {
3159 neigh = __neigh_lookup_noref(tbl, addr, dev);
3160 }
3161 if (!neigh)
3162 neigh = __neigh_create(tbl, addr, dev, false);
3163 err = PTR_ERR(neigh);
3164 if (IS_ERR(neigh)) {
3165 rcu_read_unlock();
3166 goto out_kfree_skb;
3167 }
3168 err = READ_ONCE(neigh->output)(neigh, skb);
3169 rcu_read_unlock();
3170 }
3171 else if (index == NEIGH_LINK_TABLE) {
3172 err = dev_hard_header(skb, dev, ntohs(skb->protocol),
3173 addr, NULL, skb->len);
3174 if (err < 0)
3175 goto out_kfree_skb;
3176 err = dev_queue_xmit(skb);
3177 }
3178out:
3179 return err;
3180out_kfree_skb:
3181 kfree_skb(skb);
3182 goto out;
3183}
3184EXPORT_SYMBOL(neigh_xmit);
3185
3186#ifdef CONFIG_PROC_FS
3187
3188static struct neighbour *neigh_get_first(struct seq_file *seq)
3189{
3190 struct neigh_seq_state *state = seq->private;
3191 struct net *net = seq_file_net(seq);
3192 struct neigh_hash_table *nht = state->nht;
3193 struct neighbour *n = NULL;
3194 int bucket;
3195
3196 state->flags &= ~NEIGH_SEQ_IS_PNEIGH;
3197 for (bucket = 0; bucket < (1 << nht->hash_shift); bucket++) {
3198 n = rcu_dereference(nht->hash_buckets[bucket]);
3199
3200 while (n) {
3201 if (!net_eq(dev_net(n->dev), net))
3202 goto next;
3203 if (state->neigh_sub_iter) {
3204 loff_t fakep = 0;
3205 void *v;
3206
3207 v = state->neigh_sub_iter(state, n, &fakep);
3208 if (!v)
3209 goto next;
3210 }
3211 if (!(state->flags & NEIGH_SEQ_SKIP_NOARP))
3212 break;
3213 if (READ_ONCE(n->nud_state) & ~NUD_NOARP)
3214 break;
3215next:
3216 n = rcu_dereference(n->next);
3217 }
3218
3219 if (n)
3220 break;
3221 }
3222 state->bucket = bucket;
3223
3224 return n;
3225}
3226
3227static struct neighbour *neigh_get_next(struct seq_file *seq,
3228 struct neighbour *n,
3229 loff_t *pos)
3230{
3231 struct neigh_seq_state *state = seq->private;
3232 struct net *net = seq_file_net(seq);
3233 struct neigh_hash_table *nht = state->nht;
3234
3235 if (state->neigh_sub_iter) {
3236 void *v = state->neigh_sub_iter(state, n, pos);
3237 if (v)
3238 return n;
3239 }
3240 n = rcu_dereference(n->next);
3241
3242 while (1) {
3243 while (n) {
3244 if (!net_eq(dev_net(n->dev), net))
3245 goto next;
3246 if (state->neigh_sub_iter) {
3247 void *v = state->neigh_sub_iter(state, n, pos);
3248 if (v)
3249 return n;
3250 goto next;
3251 }
3252 if (!(state->flags & NEIGH_SEQ_SKIP_NOARP))
3253 break;
3254
3255 if (READ_ONCE(n->nud_state) & ~NUD_NOARP)
3256 break;
3257next:
3258 n = rcu_dereference(n->next);
3259 }
3260
3261 if (n)
3262 break;
3263
3264 if (++state->bucket >= (1 << nht->hash_shift))
3265 break;
3266
3267 n = rcu_dereference(nht->hash_buckets[state->bucket]);
3268 }
3269
3270 if (n && pos)
3271 --(*pos);
3272 return n;
3273}
3274
3275static struct neighbour *neigh_get_idx(struct seq_file *seq, loff_t *pos)
3276{
3277 struct neighbour *n = neigh_get_first(seq);
3278
3279 if (n) {
3280 --(*pos);
3281 while (*pos) {
3282 n = neigh_get_next(seq, n, pos);
3283 if (!n)
3284 break;
3285 }
3286 }
3287 return *pos ? NULL : n;
3288}
3289
3290static struct pneigh_entry *pneigh_get_first(struct seq_file *seq)
3291{
3292 struct neigh_seq_state *state = seq->private;
3293 struct net *net = seq_file_net(seq);
3294 struct neigh_table *tbl = state->tbl;
3295 struct pneigh_entry *pn = NULL;
3296 int bucket;
3297
3298 state->flags |= NEIGH_SEQ_IS_PNEIGH;
3299 for (bucket = 0; bucket <= PNEIGH_HASHMASK; bucket++) {
3300 pn = tbl->phash_buckets[bucket];
3301 while (pn && !net_eq(pneigh_net(pn), net))
3302 pn = pn->next;
3303 if (pn)
3304 break;
3305 }
3306 state->bucket = bucket;
3307
3308 return pn;
3309}
3310
3311static struct pneigh_entry *pneigh_get_next(struct seq_file *seq,
3312 struct pneigh_entry *pn,
3313 loff_t *pos)
3314{
3315 struct neigh_seq_state *state = seq->private;
3316 struct net *net = seq_file_net(seq);
3317 struct neigh_table *tbl = state->tbl;
3318
3319 do {
3320 pn = pn->next;
3321 } while (pn && !net_eq(pneigh_net(pn), net));
3322
3323 while (!pn) {
3324 if (++state->bucket > PNEIGH_HASHMASK)
3325 break;
3326 pn = tbl->phash_buckets[state->bucket];
3327 while (pn && !net_eq(pneigh_net(pn), net))
3328 pn = pn->next;
3329 if (pn)
3330 break;
3331 }
3332
3333 if (pn && pos)
3334 --(*pos);
3335
3336 return pn;
3337}
3338
3339static struct pneigh_entry *pneigh_get_idx(struct seq_file *seq, loff_t *pos)
3340{
3341 struct pneigh_entry *pn = pneigh_get_first(seq);
3342
3343 if (pn) {
3344 --(*pos);
3345 while (*pos) {
3346 pn = pneigh_get_next(seq, pn, pos);
3347 if (!pn)
3348 break;
3349 }
3350 }
3351 return *pos ? NULL : pn;
3352}
3353
3354static void *neigh_get_idx_any(struct seq_file *seq, loff_t *pos)
3355{
3356 struct neigh_seq_state *state = seq->private;
3357 void *rc;
3358 loff_t idxpos = *pos;
3359
3360 rc = neigh_get_idx(seq, &idxpos);
3361 if (!rc && !(state->flags & NEIGH_SEQ_NEIGH_ONLY))
3362 rc = pneigh_get_idx(seq, &idxpos);
3363
3364 return rc;
3365}
3366
3367void *neigh_seq_start(struct seq_file *seq, loff_t *pos, struct neigh_table *tbl, unsigned int neigh_seq_flags)
3368 __acquires(tbl->lock)
3369 __acquires(rcu)
3370{
3371 struct neigh_seq_state *state = seq->private;
3372
3373 state->tbl = tbl;
3374 state->bucket = 0;
3375 state->flags = (neigh_seq_flags & ~NEIGH_SEQ_IS_PNEIGH);
3376
3377 rcu_read_lock();
3378 state->nht = rcu_dereference(tbl->nht);
3379 read_lock_bh(&tbl->lock);
3380
3381 return *pos ? neigh_get_idx_any(seq, pos) : SEQ_START_TOKEN;
3382}
3383EXPORT_SYMBOL(neigh_seq_start);
3384
3385void *neigh_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3386{
3387 struct neigh_seq_state *state;
3388 void *rc;
3389
3390 if (v == SEQ_START_TOKEN) {
3391 rc = neigh_get_first(seq);
3392 goto out;
3393 }
3394
3395 state = seq->private;
3396 if (!(state->flags & NEIGH_SEQ_IS_PNEIGH)) {
3397 rc = neigh_get_next(seq, v, NULL);
3398 if (rc)
3399 goto out;
3400 if (!(state->flags & NEIGH_SEQ_NEIGH_ONLY))
3401 rc = pneigh_get_first(seq);
3402 } else {
3403 BUG_ON(state->flags & NEIGH_SEQ_NEIGH_ONLY);
3404 rc = pneigh_get_next(seq, v, NULL);
3405 }
3406out:
3407 ++(*pos);
3408 return rc;
3409}
3410EXPORT_SYMBOL(neigh_seq_next);
3411
3412void neigh_seq_stop(struct seq_file *seq, void *v)
3413 __releases(tbl->lock)
3414 __releases(rcu)
3415{
3416 struct neigh_seq_state *state = seq->private;
3417 struct neigh_table *tbl = state->tbl;
3418
3419 read_unlock_bh(&tbl->lock);
3420 rcu_read_unlock();
3421}
3422EXPORT_SYMBOL(neigh_seq_stop);
3423
3424/* statistics via seq_file */
3425
3426static void *neigh_stat_seq_start(struct seq_file *seq, loff_t *pos)
3427{
3428 struct neigh_table *tbl = pde_data(file_inode(seq->file));
3429 int cpu;
3430
3431 if (*pos == 0)
3432 return SEQ_START_TOKEN;
3433
3434 for (cpu = *pos-1; cpu < nr_cpu_ids; ++cpu) {
3435 if (!cpu_possible(cpu))
3436 continue;
3437 *pos = cpu+1;
3438 return per_cpu_ptr(tbl->stats, cpu);
3439 }
3440 return NULL;
3441}
3442
3443static void *neigh_stat_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3444{
3445 struct neigh_table *tbl = pde_data(file_inode(seq->file));
3446 int cpu;
3447
3448 for (cpu = *pos; cpu < nr_cpu_ids; ++cpu) {
3449 if (!cpu_possible(cpu))
3450 continue;
3451 *pos = cpu+1;
3452 return per_cpu_ptr(tbl->stats, cpu);
3453 }
3454 (*pos)++;
3455 return NULL;
3456}
3457
3458static void neigh_stat_seq_stop(struct seq_file *seq, void *v)
3459{
3460
3461}
3462
3463static int neigh_stat_seq_show(struct seq_file *seq, void *v)
3464{
3465 struct neigh_table *tbl = pde_data(file_inode(seq->file));
3466 struct neigh_statistics *st = v;
3467
3468 if (v == SEQ_START_TOKEN) {
3469 seq_puts(seq, "entries allocs destroys hash_grows lookups hits res_failed rcv_probes_mcast rcv_probes_ucast periodic_gc_runs forced_gc_runs unresolved_discards table_fulls\n");
3470 return 0;
3471 }
3472
3473 seq_printf(seq, "%08x %08lx %08lx %08lx %08lx %08lx %08lx "
3474 "%08lx %08lx %08lx "
3475 "%08lx %08lx %08lx\n",
3476 atomic_read(&tbl->entries),
3477
3478 st->allocs,
3479 st->destroys,
3480 st->hash_grows,
3481
3482 st->lookups,
3483 st->hits,
3484
3485 st->res_failed,
3486
3487 st->rcv_probes_mcast,
3488 st->rcv_probes_ucast,
3489
3490 st->periodic_gc_runs,
3491 st->forced_gc_runs,
3492 st->unres_discards,
3493 st->table_fulls
3494 );
3495
3496 return 0;
3497}
3498
3499static const struct seq_operations neigh_stat_seq_ops = {
3500 .start = neigh_stat_seq_start,
3501 .next = neigh_stat_seq_next,
3502 .stop = neigh_stat_seq_stop,
3503 .show = neigh_stat_seq_show,
3504};
3505#endif /* CONFIG_PROC_FS */
3506
3507static void __neigh_notify(struct neighbour *n, int type, int flags,
3508 u32 pid)
3509{
3510 struct net *net = dev_net(n->dev);
3511 struct sk_buff *skb;
3512 int err = -ENOBUFS;
3513
3514 skb = nlmsg_new(neigh_nlmsg_size(), GFP_ATOMIC);
3515 if (skb == NULL)
3516 goto errout;
3517
3518 err = neigh_fill_info(skb, n, pid, 0, type, flags);
3519 if (err < 0) {
3520 /* -EMSGSIZE implies BUG in neigh_nlmsg_size() */
3521 WARN_ON(err == -EMSGSIZE);
3522 kfree_skb(skb);
3523 goto errout;
3524 }
3525 rtnl_notify(skb, net, 0, RTNLGRP_NEIGH, NULL, GFP_ATOMIC);
3526 return;
3527errout:
3528 if (err < 0)
3529 rtnl_set_sk_err(net, RTNLGRP_NEIGH, err);
3530}
3531
3532void neigh_app_ns(struct neighbour *n)
3533{
3534 __neigh_notify(n, RTM_GETNEIGH, NLM_F_REQUEST, 0);
3535}
3536EXPORT_SYMBOL(neigh_app_ns);
3537
3538#ifdef CONFIG_SYSCTL
3539static int unres_qlen_max = INT_MAX / SKB_TRUESIZE(ETH_FRAME_LEN);
3540
3541static int proc_unres_qlen(struct ctl_table *ctl, int write,
3542 void *buffer, size_t *lenp, loff_t *ppos)
3543{
3544 int size, ret;
3545 struct ctl_table tmp = *ctl;
3546
3547 tmp.extra1 = SYSCTL_ZERO;
3548 tmp.extra2 = &unres_qlen_max;
3549 tmp.data = &size;
3550
3551 size = *(int *)ctl->data / SKB_TRUESIZE(ETH_FRAME_LEN);
3552 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
3553
3554 if (write && !ret)
3555 *(int *)ctl->data = size * SKB_TRUESIZE(ETH_FRAME_LEN);
3556 return ret;
3557}
3558
3559static void neigh_copy_dflt_parms(struct net *net, struct neigh_parms *p,
3560 int index)
3561{
3562 struct net_device *dev;
3563 int family = neigh_parms_family(p);
3564
3565 rcu_read_lock();
3566 for_each_netdev_rcu(net, dev) {
3567 struct neigh_parms *dst_p =
3568 neigh_get_dev_parms_rcu(dev, family);
3569
3570 if (dst_p && !test_bit(index, dst_p->data_state))
3571 dst_p->data[index] = p->data[index];
3572 }
3573 rcu_read_unlock();
3574}
3575
3576static void neigh_proc_update(struct ctl_table *ctl, int write)
3577{
3578 struct net_device *dev = ctl->extra1;
3579 struct neigh_parms *p = ctl->extra2;
3580 struct net *net = neigh_parms_net(p);
3581 int index = (int *) ctl->data - p->data;
3582
3583 if (!write)
3584 return;
3585
3586 set_bit(index, p->data_state);
3587 if (index == NEIGH_VAR_DELAY_PROBE_TIME)
3588 call_netevent_notifiers(NETEVENT_DELAY_PROBE_TIME_UPDATE, p);
3589 if (!dev) /* NULL dev means this is default value */
3590 neigh_copy_dflt_parms(net, p, index);
3591}
3592
3593static int neigh_proc_dointvec_zero_intmax(struct ctl_table *ctl, int write,
3594 void *buffer, size_t *lenp,
3595 loff_t *ppos)
3596{
3597 struct ctl_table tmp = *ctl;
3598 int ret;
3599
3600 tmp.extra1 = SYSCTL_ZERO;
3601 tmp.extra2 = SYSCTL_INT_MAX;
3602
3603 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
3604 neigh_proc_update(ctl, write);
3605 return ret;
3606}
3607
3608static int neigh_proc_dointvec_ms_jiffies_positive(struct ctl_table *ctl, int write,
3609 void *buffer, size_t *lenp, loff_t *ppos)
3610{
3611 struct ctl_table tmp = *ctl;
3612 int ret;
3613
3614 int min = msecs_to_jiffies(1);
3615
3616 tmp.extra1 = &min;
3617 tmp.extra2 = NULL;
3618
3619 ret = proc_dointvec_ms_jiffies_minmax(&tmp, write, buffer, lenp, ppos);
3620 neigh_proc_update(ctl, write);
3621 return ret;
3622}
3623
3624int neigh_proc_dointvec(struct ctl_table *ctl, int write, void *buffer,
3625 size_t *lenp, loff_t *ppos)
3626{
3627 int ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
3628
3629 neigh_proc_update(ctl, write);
3630 return ret;
3631}
3632EXPORT_SYMBOL(neigh_proc_dointvec);
3633
3634int neigh_proc_dointvec_jiffies(struct ctl_table *ctl, int write, void *buffer,
3635 size_t *lenp, loff_t *ppos)
3636{
3637 int ret = proc_dointvec_jiffies(ctl, write, buffer, lenp, ppos);
3638
3639 neigh_proc_update(ctl, write);
3640 return ret;
3641}
3642EXPORT_SYMBOL(neigh_proc_dointvec_jiffies);
3643
3644static int neigh_proc_dointvec_userhz_jiffies(struct ctl_table *ctl, int write,
3645 void *buffer, size_t *lenp,
3646 loff_t *ppos)
3647{
3648 int ret = proc_dointvec_userhz_jiffies(ctl, write, buffer, lenp, ppos);
3649
3650 neigh_proc_update(ctl, write);
3651 return ret;
3652}
3653
3654int neigh_proc_dointvec_ms_jiffies(struct ctl_table *ctl, int write,
3655 void *buffer, size_t *lenp, loff_t *ppos)
3656{
3657 int ret = proc_dointvec_ms_jiffies(ctl, write, buffer, lenp, ppos);
3658
3659 neigh_proc_update(ctl, write);
3660 return ret;
3661}
3662EXPORT_SYMBOL(neigh_proc_dointvec_ms_jiffies);
3663
3664static int neigh_proc_dointvec_unres_qlen(struct ctl_table *ctl, int write,
3665 void *buffer, size_t *lenp,
3666 loff_t *ppos)
3667{
3668 int ret = proc_unres_qlen(ctl, write, buffer, lenp, ppos);
3669
3670 neigh_proc_update(ctl, write);
3671 return ret;
3672}
3673
3674static int neigh_proc_base_reachable_time(struct ctl_table *ctl, int write,
3675 void *buffer, size_t *lenp,
3676 loff_t *ppos)
3677{
3678 struct neigh_parms *p = ctl->extra2;
3679 int ret;
3680
3681 if (strcmp(ctl->procname, "base_reachable_time") == 0)
3682 ret = neigh_proc_dointvec_jiffies(ctl, write, buffer, lenp, ppos);
3683 else if (strcmp(ctl->procname, "base_reachable_time_ms") == 0)
3684 ret = neigh_proc_dointvec_ms_jiffies(ctl, write, buffer, lenp, ppos);
3685 else
3686 ret = -1;
3687
3688 if (write && ret == 0) {
3689 /* update reachable_time as well, otherwise, the change will
3690 * only be effective after the next time neigh_periodic_work
3691 * decides to recompute it
3692 */
3693 p->reachable_time =
3694 neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME));
3695 }
3696 return ret;
3697}
3698
3699#define NEIGH_PARMS_DATA_OFFSET(index) \
3700 (&((struct neigh_parms *) 0)->data[index])
3701
3702#define NEIGH_SYSCTL_ENTRY(attr, data_attr, name, mval, proc) \
3703 [NEIGH_VAR_ ## attr] = { \
3704 .procname = name, \
3705 .data = NEIGH_PARMS_DATA_OFFSET(NEIGH_VAR_ ## data_attr), \
3706 .maxlen = sizeof(int), \
3707 .mode = mval, \
3708 .proc_handler = proc, \
3709 }
3710
3711#define NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(attr, name) \
3712 NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_zero_intmax)
3713
3714#define NEIGH_SYSCTL_JIFFIES_ENTRY(attr, name) \
3715 NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_jiffies)
3716
3717#define NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(attr, name) \
3718 NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_userhz_jiffies)
3719
3720#define NEIGH_SYSCTL_MS_JIFFIES_POSITIVE_ENTRY(attr, name) \
3721 NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_ms_jiffies_positive)
3722
3723#define NEIGH_SYSCTL_MS_JIFFIES_REUSED_ENTRY(attr, data_attr, name) \
3724 NEIGH_SYSCTL_ENTRY(attr, data_attr, name, 0644, neigh_proc_dointvec_ms_jiffies)
3725
3726#define NEIGH_SYSCTL_UNRES_QLEN_REUSED_ENTRY(attr, data_attr, name) \
3727 NEIGH_SYSCTL_ENTRY(attr, data_attr, name, 0644, neigh_proc_dointvec_unres_qlen)
3728
3729static struct neigh_sysctl_table {
3730 struct ctl_table_header *sysctl_header;
3731 struct ctl_table neigh_vars[NEIGH_VAR_MAX + 1];
3732} neigh_sysctl_template __read_mostly = {
3733 .neigh_vars = {
3734 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(MCAST_PROBES, "mcast_solicit"),
3735 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(UCAST_PROBES, "ucast_solicit"),
3736 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(APP_PROBES, "app_solicit"),
3737 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(MCAST_REPROBES, "mcast_resolicit"),
3738 NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(RETRANS_TIME, "retrans_time"),
3739 NEIGH_SYSCTL_JIFFIES_ENTRY(BASE_REACHABLE_TIME, "base_reachable_time"),
3740 NEIGH_SYSCTL_JIFFIES_ENTRY(DELAY_PROBE_TIME, "delay_first_probe_time"),
3741 NEIGH_SYSCTL_MS_JIFFIES_POSITIVE_ENTRY(INTERVAL_PROBE_TIME_MS,
3742 "interval_probe_time_ms"),
3743 NEIGH_SYSCTL_JIFFIES_ENTRY(GC_STALETIME, "gc_stale_time"),
3744 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(QUEUE_LEN_BYTES, "unres_qlen_bytes"),
3745 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(PROXY_QLEN, "proxy_qlen"),
3746 NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(ANYCAST_DELAY, "anycast_delay"),
3747 NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(PROXY_DELAY, "proxy_delay"),
3748 NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(LOCKTIME, "locktime"),
3749 NEIGH_SYSCTL_UNRES_QLEN_REUSED_ENTRY(QUEUE_LEN, QUEUE_LEN_BYTES, "unres_qlen"),
3750 NEIGH_SYSCTL_MS_JIFFIES_REUSED_ENTRY(RETRANS_TIME_MS, RETRANS_TIME, "retrans_time_ms"),
3751 NEIGH_SYSCTL_MS_JIFFIES_REUSED_ENTRY(BASE_REACHABLE_TIME_MS, BASE_REACHABLE_TIME, "base_reachable_time_ms"),
3752 [NEIGH_VAR_GC_INTERVAL] = {
3753 .procname = "gc_interval",
3754 .maxlen = sizeof(int),
3755 .mode = 0644,
3756 .proc_handler = proc_dointvec_jiffies,
3757 },
3758 [NEIGH_VAR_GC_THRESH1] = {
3759 .procname = "gc_thresh1",
3760 .maxlen = sizeof(int),
3761 .mode = 0644,
3762 .extra1 = SYSCTL_ZERO,
3763 .extra2 = SYSCTL_INT_MAX,
3764 .proc_handler = proc_dointvec_minmax,
3765 },
3766 [NEIGH_VAR_GC_THRESH2] = {
3767 .procname = "gc_thresh2",
3768 .maxlen = sizeof(int),
3769 .mode = 0644,
3770 .extra1 = SYSCTL_ZERO,
3771 .extra2 = SYSCTL_INT_MAX,
3772 .proc_handler = proc_dointvec_minmax,
3773 },
3774 [NEIGH_VAR_GC_THRESH3] = {
3775 .procname = "gc_thresh3",
3776 .maxlen = sizeof(int),
3777 .mode = 0644,
3778 .extra1 = SYSCTL_ZERO,
3779 .extra2 = SYSCTL_INT_MAX,
3780 .proc_handler = proc_dointvec_minmax,
3781 },
3782 {},
3783 },
3784};
3785
3786int neigh_sysctl_register(struct net_device *dev, struct neigh_parms *p,
3787 proc_handler *handler)
3788{
3789 int i;
3790 struct neigh_sysctl_table *t;
3791 const char *dev_name_source;
3792 char neigh_path[ sizeof("net//neigh/") + IFNAMSIZ + IFNAMSIZ ];
3793 char *p_name;
3794 size_t neigh_vars_size;
3795
3796 t = kmemdup(&neigh_sysctl_template, sizeof(*t), GFP_KERNEL_ACCOUNT);
3797 if (!t)
3798 goto err;
3799
3800 for (i = 0; i < NEIGH_VAR_GC_INTERVAL; i++) {
3801 t->neigh_vars[i].data += (long) p;
3802 t->neigh_vars[i].extra1 = dev;
3803 t->neigh_vars[i].extra2 = p;
3804 }
3805
3806 neigh_vars_size = ARRAY_SIZE(t->neigh_vars);
3807 if (dev) {
3808 dev_name_source = dev->name;
3809 /* Terminate the table early */
3810 memset(&t->neigh_vars[NEIGH_VAR_GC_INTERVAL], 0,
3811 sizeof(t->neigh_vars[NEIGH_VAR_GC_INTERVAL]));
3812 neigh_vars_size = NEIGH_VAR_BASE_REACHABLE_TIME_MS + 1;
3813 } else {
3814 struct neigh_table *tbl = p->tbl;
3815 dev_name_source = "default";
3816 t->neigh_vars[NEIGH_VAR_GC_INTERVAL].data = &tbl->gc_interval;
3817 t->neigh_vars[NEIGH_VAR_GC_THRESH1].data = &tbl->gc_thresh1;
3818 t->neigh_vars[NEIGH_VAR_GC_THRESH2].data = &tbl->gc_thresh2;
3819 t->neigh_vars[NEIGH_VAR_GC_THRESH3].data = &tbl->gc_thresh3;
3820 }
3821
3822 if (handler) {
3823 /* RetransTime */
3824 t->neigh_vars[NEIGH_VAR_RETRANS_TIME].proc_handler = handler;
3825 /* ReachableTime */
3826 t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME].proc_handler = handler;
3827 /* RetransTime (in milliseconds)*/
3828 t->neigh_vars[NEIGH_VAR_RETRANS_TIME_MS].proc_handler = handler;
3829 /* ReachableTime (in milliseconds) */
3830 t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME_MS].proc_handler = handler;
3831 } else {
3832 /* Those handlers will update p->reachable_time after
3833 * base_reachable_time(_ms) is set to ensure the new timer starts being
3834 * applied after the next neighbour update instead of waiting for
3835 * neigh_periodic_work to update its value (can be multiple minutes)
3836 * So any handler that replaces them should do this as well
3837 */
3838 /* ReachableTime */
3839 t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME].proc_handler =
3840 neigh_proc_base_reachable_time;
3841 /* ReachableTime (in milliseconds) */
3842 t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME_MS].proc_handler =
3843 neigh_proc_base_reachable_time;
3844 }
3845
3846 switch (neigh_parms_family(p)) {
3847 case AF_INET:
3848 p_name = "ipv4";
3849 break;
3850 case AF_INET6:
3851 p_name = "ipv6";
3852 break;
3853 default:
3854 BUG();
3855 }
3856
3857 snprintf(neigh_path, sizeof(neigh_path), "net/%s/neigh/%s",
3858 p_name, dev_name_source);
3859 t->sysctl_header = register_net_sysctl_sz(neigh_parms_net(p),
3860 neigh_path, t->neigh_vars,
3861 neigh_vars_size);
3862 if (!t->sysctl_header)
3863 goto free;
3864
3865 p->sysctl_table = t;
3866 return 0;
3867
3868free:
3869 kfree(t);
3870err:
3871 return -ENOBUFS;
3872}
3873EXPORT_SYMBOL(neigh_sysctl_register);
3874
3875void neigh_sysctl_unregister(struct neigh_parms *p)
3876{
3877 if (p->sysctl_table) {
3878 struct neigh_sysctl_table *t = p->sysctl_table;
3879 p->sysctl_table = NULL;
3880 unregister_net_sysctl_table(t->sysctl_header);
3881 kfree(t);
3882 }
3883}
3884EXPORT_SYMBOL(neigh_sysctl_unregister);
3885
3886#endif /* CONFIG_SYSCTL */
3887
3888static int __init neigh_init(void)
3889{
3890 rtnl_register(PF_UNSPEC, RTM_NEWNEIGH, neigh_add, NULL, 0);
3891 rtnl_register(PF_UNSPEC, RTM_DELNEIGH, neigh_delete, NULL, 0);
3892 rtnl_register(PF_UNSPEC, RTM_GETNEIGH, neigh_get, neigh_dump_info, 0);
3893
3894 rtnl_register(PF_UNSPEC, RTM_GETNEIGHTBL, NULL, neightbl_dump_info,
3895 0);
3896 rtnl_register(PF_UNSPEC, RTM_SETNEIGHTBL, neightbl_set, NULL, 0);
3897
3898 return 0;
3899}
3900
3901subsys_initcall(neigh_init);