net/core/neighbour.c

   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/config.h>
  19 #include <linux/types.h>
  20 #include <linux/kernel.h>
  21 #include <linux/module.h>
  22 #include <linux/socket.h>
  23 #include <linux/sched.h>
  24 #include <linux/netdevice.h>
  25 #include <linux/proc_fs.h>
  26 #ifdef CONFIG_SYSCTL
  27 #include <linux/sysctl.h>
  28 #endif
  29 #include <linux/times.h>
  30 #include <net/neighbour.h>
  31 #include <net/dst.h>
  32 #include <net/sock.h>
  33 #include <linux/rtnetlink.h>
  34 #include <linux/random.h>
  35 #include <linux/string.h>
  36
  37 #define NEIGH_DEBUG 1
  38
  39 #define NEIGH_PRINTK(x...) printk(x)
  40 #define NEIGH_NOPRINTK(x...) do { ; } while(0)
  41 #define NEIGH_PRINTK0 NEIGH_PRINTK
  42 #define NEIGH_PRINTK1 NEIGH_NOPRINTK
  43 #define NEIGH_PRINTK2 NEIGH_NOPRINTK
  44
  45 #if NEIGH_DEBUG >= 1
  46 #undef NEIGH_PRINTK1
  47 #define NEIGH_PRINTK1 NEIGH_PRINTK
  48 #endif
  49 #if NEIGH_DEBUG >= 2
  50 #undef NEIGH_PRINTK2
  51 #define NEIGH_PRINTK2 NEIGH_PRINTK
  52 #endif
  53
  54 #define PNEIGH_HASHMASK         0xF
  55
  56 static void neigh_timer_handler(unsigned long arg);
  57 #ifdef CONFIG_ARPD
  58 static void neigh_app_notify(struct neighbour *n);
  59 #endif
  60 static int pneigh_ifdown(struct neigh_table *tbl, struct net_device *dev);
  61 void neigh_changeaddr(struct neigh_table *tbl, struct net_device *dev);
  62
  63 static struct neigh_table *neigh_tables;
  64 static struct file_operations neigh_stat_seq_fops;
  65
  66 /*
  67    Neighbour hash table buckets are protected with rwlock tbl->lock.
  68
  69    - All the scans/updates to hash buckets MUST be made under this lock.
  70    - NOTHING clever should be made under this lock: no callbacks
  71      to protocol backends, no attempts to send something to network.
  72      It will result in deadlocks, if backend/driver wants to use neighbour
  73      cache.
  74    - If the entry requires some non-trivial actions, increase
  75      its reference count and release table lock.
  76
  77    Neighbour entries are protected:
  78    - with reference count.
  79    - with rwlock neigh->lock
  80
  81    Reference count prevents destruction.
  82
  83    neigh->lock mainly serializes ll address data and its validity state.
  84    However, the same lock is used to protect another entry fields:
  85     - timer
  86     - resolution queue
  87
  88    Again, nothing clever shall be made under neigh->lock,
  89    the most complicated procedure, which we allow is dev->hard_header.
  90    It is supposed, that dev->hard_header is simplistic and does
  91    not make callbacks to neighbour tables.
  92
  93    The last lock is neigh_tbl_lock. It is pure SMP lock, protecting
  94    list of neighbour tables. This list is used only in process context,
  95  */
  96
  97 static DEFINE_RWLOCK(neigh_tbl_lock);
  98
  99 static int neigh_blackhole(struct sk_buff *skb)
 100 {
 101         kfree_skb(skb);
 102         return -ENETDOWN;
 103 }
 104
 105 /*
 106  * It is random distribution in the interval (1/2)*base...(3/2)*base.
 107  * It corresponds to default IPv6 settings and is not overridable,
 108  * because it is really reasonable choice.
 109  */
 110
 111 unsigned long neigh_rand_reach_time(unsigned long base)
 112 {
 113         return (base ? (net_random() % base) + (base >> 1) : 0);
 114 }
 115
 116
 117 static int neigh_forced_gc(struct neigh_table *tbl)
 118 {
 119         int shrunk = 0;
 120         int i;
 121
 122         NEIGH_CACHE_STAT_INC(tbl, forced_gc_runs);
 123
 124         write_lock_bh(&tbl->lock);
 125         for (i = 0; i <= tbl->hash_mask; i++) {
 126                 struct neighbour *n, **np;
 127
 128                 np = &tbl->hash_buckets[i];
 129                 while ((n = *np) != NULL) {
 130                         /* Neighbour record may be discarded if:
 131                          * - nobody refers to it.
 132                          * - it is not permanent
 133                          */
 134                         write_lock(&n->lock);
 135                         if (atomic_read(&n->refcnt) == 1 &&
 136                             !(n->nud_state & NUD_PERMANENT)) {
 137                                 *np     = n->next;
 138                                 n->dead = 1;
 139                                 shrunk  = 1;
 140                                 write_unlock(&n->lock);
 141                                 neigh_release(n);
 142                                 continue;
 143                         }
 144                         write_unlock(&n->lock);
 145                         np = &n->next;
 146                 }
 147         }
 148
 149         tbl->last_flush = jiffies;
 150
 151         write_unlock_bh(&tbl->lock);
 152
 153         return shrunk;
 154 }
 155
 156 static int neigh_del_timer(struct neighbour *n)
 157 {
 158         if ((n->nud_state & NUD_IN_TIMER) &&
 159             del_timer(&n->timer)) {
 160                 neigh_release(n);
 161                 return 1;
 162         }
 163         return 0;
 164 }
 165
 166 static void pneigh_queue_purge(struct sk_buff_head *list)
 167 {
 168         struct sk_buff *skb;
 169
 170         while ((skb = skb_dequeue(list)) != NULL) {
 171                 dev_put(skb->dev);
 172                 kfree_skb(skb);
 173         }
 174 }
 175
 176 void neigh_changeaddr(struct neigh_table *tbl, struct net_device *dev)
 177 {
 178         int i;
 179
 180         write_lock_bh(&tbl->lock);
 181
 182         for (i=0; i <= tbl->hash_mask; i++) {
 183                 struct neighbour *n, **np;
 184
 185                 np = &tbl->hash_buckets[i];
 186                 while ((n = *np) != NULL) {
 187                         if (dev && n->dev != dev) {
 188                                 np = &n->next;
 189                                 continue;
 190                         }
 191                         *np = n->next;
 192                         write_lock_bh(&n->lock);
 193                         n->dead = 1;
 194                         neigh_del_timer(n);
 195                         write_unlock_bh(&n->lock);
 196                         neigh_release(n);
 197                 }
 198         }
 199
 200         write_unlock_bh(&tbl->lock);
 201 }
 202
 203 int neigh_ifdown(struct neigh_table *tbl, struct net_device *dev)
 204 {
 205         int i;
 206
 207         write_lock_bh(&tbl->lock);
 208
 209         for (i = 0; i <= tbl->hash_mask; i++) {
 210                 struct neighbour *n, **np = &tbl->hash_buckets[i];
 211
 212                 while ((n = *np) != NULL) {
 213                         if (dev && n->dev != dev) {
 214                                 np = &n->next;
 215                                 continue;
 216                         }
 217                         *np = n->next;
 218                         write_lock(&n->lock);
 219                         neigh_del_timer(n);
 220                         n->dead = 1;
 221
 222                         if (atomic_read(&n->refcnt) != 1) {
 223                                 /* The most unpleasant situation.
 224                                    We must destroy neighbour entry,
 225                                    but someone still uses it.
 226
 227                                    The destroy will be delayed until
 228                                    the last user releases us, but
 229                                    we must kill timers etc. and move
 230                                    it to safe state.
 231                                  */
 232                                 skb_queue_purge(&n->arp_queue);
 233                                 n->output = neigh_blackhole;
 234                                 if (n->nud_state & NUD_VALID)
 235                                         n->nud_state = NUD_NOARP;
 236                                 else
 237                                         n->nud_state = NUD_NONE;
 238                                 NEIGH_PRINTK2("neigh %p is stray.\n", n);
 239                         }
 240                         write_unlock(&n->lock);
 241                         neigh_release(n);
 242                 }
 243         }
 244
 245         pneigh_ifdown(tbl, dev);
 246         write_unlock_bh(&tbl->lock);
 247
 248         del_timer_sync(&tbl->proxy_timer);
 249         pneigh_queue_purge(&tbl->proxy_queue);
 250         return 0;
 251 }
 252
 253 static struct neighbour *neigh_alloc(struct neigh_table *tbl)
 254 {
 255         struct neighbour *n = NULL;
 256         unsigned long now = jiffies;
 257         int entries;
 258
 259         entries = atomic_inc_return(&tbl->entries) - 1;
 260         if (entries >= tbl->gc_thresh3 ||
 261             (entries >= tbl->gc_thresh2 &&
 262              time_after(now, tbl->last_flush + 5 * HZ))) {
 263                 if (!neigh_forced_gc(tbl) &&
 264                     entries >= tbl->gc_thresh3)
 265                         goto out_entries;
 266         }
 267
 268         n = kmem_cache_alloc(tbl->kmem_cachep, SLAB_ATOMIC);
 269         if (!n)
 270                 goto out_entries;
 271
 272         memset(n, 0, tbl->entry_size);
 273
 274         skb_queue_head_init(&n->arp_queue);
 275         rwlock_init(&n->lock);
 276         n->updated        = n->used = now;
 277         n->nud_state      = NUD_NONE;
 278         n->output         = neigh_blackhole;
 279         n->parms          = neigh_parms_clone(&tbl->parms);
 280         init_timer(&n->timer);
 281         n->timer.function = neigh_timer_handler;
 282         n->timer.data     = (unsigned long)n;
 283
 284         NEIGH_CACHE_STAT_INC(tbl, allocs);
 285         n->tbl            = tbl;
 286         atomic_set(&n->refcnt, 1);
 287         n->dead           = 1;
 288 out:
 289         return n;
 290
 291 out_entries:
 292         atomic_dec(&tbl->entries);
 293         goto out;
 294 }
 295
 296 static struct neighbour **neigh_hash_alloc(unsigned int entries)
 297 {
 298         unsigned long size = entries * sizeof(struct neighbour *);
 299         struct neighbour **ret;
 300
 301         if (size <= PAGE_SIZE) {
 302                 ret = kmalloc(size, GFP_ATOMIC);
 303         } else {
 304                 ret = (struct neighbour **)
 305                         __get_free_pages(GFP_ATOMIC, get_order(size));
 306         }
 307         if (ret)
 308                 memset(ret, 0, size);
 309
 310         return ret;
 311 }
 312
 313 static void neigh_hash_free(struct neighbour **hash, unsigned int entries)
 314 {
 315         unsigned long size = entries * sizeof(struct neighbour *);
 316
 317         if (size <= PAGE_SIZE)
 318                 kfree(hash);
 319         else
 320                 free_pages((unsigned long)hash, get_order(size));
 321 }
 322
 323 static void neigh_hash_grow(struct neigh_table *tbl, unsigned long new_entries)
 324 {
 325         struct neighbour **new_hash, **old_hash;
 326         unsigned int i, new_hash_mask, old_entries;
 327
 328         NEIGH_CACHE_STAT_INC(tbl, hash_grows);
 329
 330         BUG_ON(new_entries & (new_entries - 1));
 331         new_hash = neigh_hash_alloc(new_entries);
 332         if (!new_hash)
 333                 return;
 334
 335         old_entries = tbl->hash_mask + 1;
 336         new_hash_mask = new_entries - 1;
 337         old_hash = tbl->hash_buckets;
 338
 339         get_random_bytes(&tbl->hash_rnd, sizeof(tbl->hash_rnd));
 340         for (i = 0; i < old_entries; i++) {
 341                 struct neighbour *n, *next;
 342
 343                 for (n = old_hash[i]; n; n = next) {
 344                         unsigned int hash_val = tbl->hash(n->primary_key, n->dev);
 345
 346                         hash_val &= new_hash_mask;
 347                         next = n->next;
 348
 349                         n->next = new_hash[hash_val];
 350                         new_hash[hash_val] = n;
 351                 }
 352         }
 353         tbl->hash_buckets = new_hash;
 354         tbl->hash_mask = new_hash_mask;
 355
 356         neigh_hash_free(old_hash, old_entries);
 357 }
 358
 359 struct neighbour *neigh_lookup(struct neigh_table *tbl, const void *pkey,
 360                                struct net_device *dev)
 361 {
 362         struct neighbour *n;
 363         int key_len = tbl->key_len;
 364         u32 hash_val = tbl->hash(pkey, dev) & tbl->hash_mask;
 365
 366         NEIGH_CACHE_STAT_INC(tbl, lookups);
 367
 368         read_lock_bh(&tbl->lock);
 369         for (n = tbl->hash_buckets[hash_val]; n; n = n->next) {
 370                 if (dev == n->dev && !memcmp(n->primary_key, pkey, key_len)) {
 371                         neigh_hold(n);
 372                         NEIGH_CACHE_STAT_INC(tbl, hits);
 373                         break;
 374                 }
 375         }
 376         read_unlock_bh(&tbl->lock);
 377         return n;
 378 }
 379
 380 struct neighbour *neigh_lookup_nodev(struct neigh_table *tbl, const void *pkey)
 381 {
 382         struct neighbour *n;
 383         int key_len = tbl->key_len;
 384         u32 hash_val = tbl->hash(pkey, NULL) & tbl->hash_mask;
 385
 386         NEIGH_CACHE_STAT_INC(tbl, lookups);
 387
 388         read_lock_bh(&tbl->lock);
 389         for (n = tbl->hash_buckets[hash_val]; n; n = n->next) {
 390                 if (!memcmp(n->primary_key, pkey, key_len)) {
 391                         neigh_hold(n);
 392                         NEIGH_CACHE_STAT_INC(tbl, hits);
 393                         break;
 394                 }
 395         }
 396         read_unlock_bh(&tbl->lock);
 397         return n;
 398 }
 399
 400 struct neighbour *neigh_create(struct neigh_table *tbl, const void *pkey,
 401                                struct net_device *dev)
 402 {
 403         u32 hash_val;
 404         int key_len = tbl->key_len;
 405         int error;
 406         struct neighbour *n1, *rc, *n = neigh_alloc(tbl);
 407
 408         if (!n) {
 409                 rc = ERR_PTR(-ENOBUFS);
 410                 goto out;
 411         }
 412
 413         memcpy(n->primary_key, pkey, key_len);
 414         n->dev = dev;
 415         dev_hold(dev);
 416
 417         /* Protocol specific setup. */
 418         if (tbl->constructor && (error = tbl->constructor(n)) < 0) {
 419                 rc = ERR_PTR(error);
 420                 goto out_neigh_release;
 421         }
 422
 423         /* Device specific setup. */
 424         if (n->parms->neigh_setup &&
 425             (error = n->parms->neigh_setup(n)) < 0) {
 426                 rc = ERR_PTR(error);
 427                 goto out_neigh_release;
 428         }
 429
 430         n->confirmed = jiffies - (n->parms->base_reachable_time << 1);
 431
 432         write_lock_bh(&tbl->lock);
 433
 434         if (atomic_read(&tbl->entries) > (tbl->hash_mask + 1))
 435                 neigh_hash_grow(tbl, (tbl->hash_mask + 1) << 1);
 436
 437         hash_val = tbl->hash(pkey, dev) & tbl->hash_mask;
 438
 439         if (n->parms->dead) {
 440                 rc = ERR_PTR(-EINVAL);
 441                 goto out_tbl_unlock;
 442         }
 443
 444         for (n1 = tbl->hash_buckets[hash_val]; n1; n1 = n1->next) {
 445                 if (dev == n1->dev && !memcmp(n1->primary_key, pkey, key_len)) {
 446                         neigh_hold(n1);
 447                         rc = n1;
 448                         goto out_tbl_unlock;
 449                 }
 450         }
 451
 452         n->next = tbl->hash_buckets[hash_val];
 453         tbl->hash_buckets[hash_val] = n;
 454         n->dead = 0;
 455         neigh_hold(n);
 456         write_unlock_bh(&tbl->lock);
 457         NEIGH_PRINTK2("neigh %p is created.\n", n);
 458         rc = n;
 459 out:
 460         return rc;
 461 out_tbl_unlock:
 462         write_unlock_bh(&tbl->lock);
 463 out_neigh_release:
 464         neigh_release(n);
 465         goto out;
 466 }
 467
 468 struct pneigh_entry * pneigh_lookup(struct neigh_table *tbl, const void *pkey,
 469                                     struct net_device *dev, int creat)
 470 {
 471         struct pneigh_entry *n;
 472         int key_len = tbl->key_len;
 473         u32 hash_val = *(u32 *)(pkey + key_len - 4);
 474
 475         hash_val ^= (hash_val >> 16);
 476         hash_val ^= hash_val >> 8;
 477         hash_val ^= hash_val >> 4;
 478         hash_val &= PNEIGH_HASHMASK;
 479
 480         read_lock_bh(&tbl->lock);
 481
 482         for (n = tbl->phash_buckets[hash_val]; n; n = n->next) {
 483                 if (!memcmp(n->key, pkey, key_len) &&
 484                     (n->dev == dev || !n->dev)) {
 485                         read_unlock_bh(&tbl->lock);
 486                         goto out;
 487                 }
 488         }
 489         read_unlock_bh(&tbl->lock);
 490         n = NULL;
 491         if (!creat)
 492                 goto out;
 493
 494         n = kmalloc(sizeof(*n) + key_len, GFP_KERNEL);
 495         if (!n)
 496                 goto out;
 497
 498         memcpy(n->key, pkey, key_len);
 499         n->dev = dev;
 500         if (dev)
 501                 dev_hold(dev);
 502
 503         if (tbl->pconstructor && tbl->pconstructor(n)) {
 504                 if (dev)
 505                         dev_put(dev);
 506                 kfree(n);
 507                 n = NULL;
 508                 goto out;
 509         }
 510
 511         write_lock_bh(&tbl->lock);
 512         n->next = tbl->phash_buckets[hash_val];
 513         tbl->phash_buckets[hash_val] = n;
 514         write_unlock_bh(&tbl->lock);
 515 out:
 516         return n;
 517 }
 518
 519
 520 int pneigh_delete(struct neigh_table *tbl, const void *pkey,
 521                   struct net_device *dev)
 522 {
 523         struct pneigh_entry *n, **np;
 524         int key_len = tbl->key_len;
 525         u32 hash_val = *(u32 *)(pkey + key_len - 4);
 526
 527         hash_val ^= (hash_val >> 16);
 528         hash_val ^= hash_val >> 8;
 529         hash_val ^= hash_val >> 4;
 530         hash_val &= PNEIGH_HASHMASK;
 531
 532         write_lock_bh(&tbl->lock);
 533         for (np = &tbl->phash_buckets[hash_val]; (n = *np) != NULL;
 534              np = &n->next) {
 535                 if (!memcmp(n->key, pkey, key_len) && n->dev == dev) {
 536                         *np = n->next;
 537                         write_unlock_bh(&tbl->lock);
 538                         if (tbl->pdestructor)
 539                                 tbl->pdestructor(n);
 540                         if (n->dev)
 541                                 dev_put(n->dev);
 542                         kfree(n);
 543                         return 0;
 544                 }
 545         }
 546         write_unlock_bh(&tbl->lock);
 547         return -ENOENT;
 548 }
 549
 550 static int pneigh_ifdown(struct neigh_table *tbl, struct net_device *dev)
 551 {
 552         struct pneigh_entry *n, **np;
 553         u32 h;
 554
 555         for (h = 0; h <= PNEIGH_HASHMASK; h++) {
 556                 np = &tbl->phash_buckets[h];
 557                 while ((n = *np) != NULL) {
 558                         if (!dev || n->dev == dev) {
 559                                 *np = n->next;
 560                                 if (tbl->pdestructor)
 561                                         tbl->pdestructor(n);
 562                                 if (n->dev)
 563                                         dev_put(n->dev);
 564                                 kfree(n);
 565                                 continue;
 566                         }
 567                         np = &n->next;
 568                 }
 569         }
 570         return -ENOENT;
 571 }
 572
 573
 574 /*
 575  *      neighbour must already be out of the table;
 576  *
 577  */
 578 void neigh_destroy(struct neighbour *neigh)
 579 {
 580         struct hh_cache *hh;
 581
 582         NEIGH_CACHE_STAT_INC(neigh->tbl, destroys);
 583
 584         if (!neigh->dead) {
 585                 printk(KERN_WARNING
 586                        "Destroying alive neighbour %p\n", neigh);
 587                 dump_stack();
 588                 return;
 589         }
 590
 591         if (neigh_del_timer(neigh))
 592                 printk(KERN_WARNING "Impossible event.\n");
 593
 594         while ((hh = neigh->hh) != NULL) {
 595                 neigh->hh = hh->hh_next;
 596                 hh->hh_next = NULL;
 597                 write_lock_bh(&hh->hh_lock);
 598                 hh->hh_output = neigh_blackhole;
 599                 write_unlock_bh(&hh->hh_lock);
 600                 if (atomic_dec_and_test(&hh->hh_refcnt))
 601                         kfree(hh);
 602         }
 603
 604         if (neigh->ops && neigh->ops->destructor)
 605                 (neigh->ops->destructor)(neigh);
 606
 607         skb_queue_purge(&neigh->arp_queue);
 608
 609         dev_put(neigh->dev);
 610         neigh_parms_put(neigh->parms);
 611
 612         NEIGH_PRINTK2("neigh %p is destroyed.\n", neigh);
 613
 614         atomic_dec(&neigh->tbl->entries);
 615         kmem_cache_free(neigh->tbl->kmem_cachep, neigh);
 616 }
 617
 618 /* Neighbour state is suspicious;
 619    disable fast path.
 620
 621    Called with write_locked neigh.
 622  */
 623 static void neigh_suspect(struct neighbour *neigh)
 624 {
 625         struct hh_cache *hh;
 626
 627         NEIGH_PRINTK2("neigh %p is suspected.\n", neigh);
 628
 629         neigh->output = neigh->ops->output;
 630
 631         for (hh = neigh->hh; hh; hh = hh->hh_next)
 632                 hh->hh_output = neigh->ops->output;
 633 }
 634
 635 /* Neighbour state is OK;
 636    enable fast path.
 637
 638    Called with write_locked neigh.
 639  */
 640 static void neigh_connect(struct neighbour *neigh)
 641 {
 642         struct hh_cache *hh;
 643
 644         NEIGH_PRINTK2("neigh %p is connected.\n", neigh);
 645
 646         neigh->output = neigh->ops->connected_output;
 647
 648         for (hh = neigh->hh; hh; hh = hh->hh_next)
 649                 hh->hh_output = neigh->ops->hh_output;
 650 }
 651
 652 static void neigh_periodic_timer(unsigned long arg)
 653 {
 654         struct neigh_table *tbl = (struct neigh_table *)arg;
 655         struct neighbour *n, **np;
 656         unsigned long expire, now = jiffies;
 657
 658         NEIGH_CACHE_STAT_INC(tbl, periodic_gc_runs);
 659
 660         write_lock(&tbl->lock);
 661
 662         /*
 663          *      periodically recompute ReachableTime from random function
 664          */
 665
 666         if (time_after(now, tbl->last_rand + 300 * HZ)) {
 667                 struct neigh_parms *p;
 668                 tbl->last_rand = now;
 669                 for (p = &tbl->parms; p; p = p->next)
 670                         p->reachable_time =
 671                                 neigh_rand_reach_time(p->base_reachable_time);
 672         }
 673
 674         np = &tbl->hash_buckets[tbl->hash_chain_gc];
 675         tbl->hash_chain_gc = ((tbl->hash_chain_gc + 1) & tbl->hash_mask);
 676
 677         while ((n = *np) != NULL) {
 678                 unsigned int state;
 679
 680                 write_lock(&n->lock);
 681
 682                 state = n->nud_state;
 683                 if (state & (NUD_PERMANENT | NUD_IN_TIMER)) {
 684                         write_unlock(&n->lock);
 685                         goto next_elt;
 686                 }
 687
 688                 if (time_before(n->used, n->confirmed))
 689                         n->used = n->confirmed;
 690
 691                 if (atomic_read(&n->refcnt) == 1 &&
 692                     (state == NUD_FAILED ||
 693                      time_after(now, n->used + n->parms->gc_staletime))) {
 694                         *np = n->next;
 695                         n->dead = 1;
 696                         write_unlock(&n->lock);
 697                         neigh_release(n);
 698                         continue;
 699                 }
 700                 write_unlock(&n->lock);
 701
 702 next_elt:
 703                 np = &n->next;
 704         }
 705
 706         /* Cycle through all hash buckets every base_reachable_time/2 ticks.
 707          * ARP entry timeouts range from 1/2 base_reachable_time to 3/2
 708          * base_reachable_time.
 709          */
 710         expire = tbl->parms.base_reachable_time >> 1;
 711         expire /= (tbl->hash_mask + 1);
 712         if (!expire)
 713                 expire = 1;
 714
 715         mod_timer(&tbl->gc_timer, now + expire);
 716
 717         write_unlock(&tbl->lock);
 718 }
 719
 720 static __inline__ int neigh_max_probes(struct neighbour *n)
 721 {
 722         struct neigh_parms *p = n->parms;
 723         return (n->nud_state & NUD_PROBE ?
 724                 p->ucast_probes :
 725                 p->ucast_probes + p->app_probes + p->mcast_probes);
 726 }
 727
 728
 729 /* Called when a timer expires for a neighbour entry. */
 730
 731 static void neigh_timer_handler(unsigned long arg)
 732 {
 733         unsigned long now, next;
 734         struct neighbour *neigh = (struct neighbour *)arg;
 735         unsigned state;
 736         int notify = 0;
 737
 738         write_lock(&neigh->lock);
 739
 740         state = neigh->nud_state;
 741         now = jiffies;
 742         next = now + HZ;
 743
 744         if (!(state & NUD_IN_TIMER)) {
 745 #ifndef CONFIG_SMP
 746                 printk(KERN_WARNING "neigh: timer & !nud_in_timer\n");
 747 #endif
 748                 goto out;
 749         }
 750
 751         if (state & NUD_REACHABLE) {
 752                 if (time_before_eq(now,
 753                                    neigh->confirmed + neigh->parms->reachable_time)) {
 754                         NEIGH_PRINTK2("neigh %p is still alive.\n", neigh);
 755                         next = neigh->confirmed + neigh->parms->reachable_time;
 756                 } else if (time_before_eq(now,
 757                                           neigh->used + neigh->parms->delay_probe_time)) {
 758                         NEIGH_PRINTK2("neigh %p is delayed.\n", neigh);
 759                         neigh->nud_state = NUD_DELAY;
 760                         neigh_suspect(neigh);
 761                         next = now + neigh->parms->delay_probe_time;
 762                 } else {
 763                         NEIGH_PRINTK2("neigh %p is suspected.\n", neigh);
 764                         neigh->nud_state = NUD_STALE;
 765                         neigh_suspect(neigh);
 766                 }
 767         } else if (state & NUD_DELAY) {
 768                 if (time_before_eq(now,
 769                                    neigh->confirmed + neigh->parms->delay_probe_time)) {
 770                         NEIGH_PRINTK2("neigh %p is now reachable.\n", neigh);
 771                         neigh->nud_state = NUD_REACHABLE;
 772                         neigh_connect(neigh);
 773                         next = neigh->confirmed + neigh->parms->reachable_time;
 774                 } else {
 775                         NEIGH_PRINTK2("neigh %p is probed.\n", neigh);
 776                         neigh->nud_state = NUD_PROBE;
 777                         atomic_set(&neigh->probes, 0);
 778                         next = now + neigh->parms->retrans_time;
 779                 }
 780         } else {
 781                 /* NUD_PROBE|NUD_INCOMPLETE */
 782                 next = now + neigh->parms->retrans_time;
 783         }
 784
 785         if ((neigh->nud_state & (NUD_INCOMPLETE | NUD_PROBE)) &&
 786             atomic_read(&neigh->probes) >= neigh_max_probes(neigh)) {
 787                 struct sk_buff *skb;
 788
 789                 neigh->nud_state = NUD_FAILED;
 790                 notify = 1;
 791                 NEIGH_CACHE_STAT_INC(neigh->tbl, res_failed);
 792                 NEIGH_PRINTK2("neigh %p is failed.\n", neigh);
 793
 794                 /* It is very thin place. report_unreachable is very complicated
 795                    routine. Particularly, it can hit the same neighbour entry!
 796
 797                    So that, we try to be accurate and avoid dead loop. --ANK
 798                  */
 799                 while (neigh->nud_state == NUD_FAILED &&
 800                        (skb = __skb_dequeue(&neigh->arp_queue)) != NULL) {
 801                         write_unlock(&neigh->lock);
 802                         neigh->ops->error_report(neigh, skb);
 803                         write_lock(&neigh->lock);
 804                 }
 805                 skb_queue_purge(&neigh->arp_queue);
 806         }
 807
 808         if (neigh->nud_state & NUD_IN_TIMER) {
 809                 neigh_hold(neigh);
 810                 if (time_before(next, jiffies + HZ/2))
 811                         next = jiffies + HZ/2;
 812                 neigh->timer.expires = next;
 813                 add_timer(&neigh->timer);
 814         }
 815         if (neigh->nud_state & (NUD_INCOMPLETE | NUD_PROBE)) {
 816                 struct sk_buff *skb = skb_peek(&neigh->arp_queue);
 817                 /* keep skb alive even if arp_queue overflows */
 818                 if (skb)
 819                         skb_get(skb);
 820                 write_unlock(&neigh->lock);
 821                 neigh->ops->solicit(neigh, skb);
 822                 atomic_inc(&neigh->probes);
 823                 if (skb)
 824                         kfree_skb(skb);
 825         } else {
 826 out:
 827                 write_unlock(&neigh->lock);
 828         }
 829
 830 #ifdef CONFIG_ARPD
 831         if (notify && neigh->parms->app_probes)
 832                 neigh_app_notify(neigh);
 833 #endif
 834         neigh_release(neigh);
 835 }
 836
 837 int __neigh_event_send(struct neighbour *neigh, struct sk_buff *skb)
 838 {
 839         int rc;
 840         unsigned long now;
 841
 842         write_lock_bh(&neigh->lock);
 843
 844         rc = 0;
 845         if (neigh->nud_state & (NUD_CONNECTED | NUD_DELAY | NUD_PROBE))
 846                 goto out_unlock_bh;
 847
 848         now = jiffies;
 849
 850         if (!(neigh->nud_state & (NUD_STALE | NUD_INCOMPLETE))) {
 851                 if (neigh->parms->mcast_probes + neigh->parms->app_probes) {
 852                         atomic_set(&neigh->probes, neigh->parms->ucast_probes);
 853                         neigh->nud_state     = NUD_INCOMPLETE;
 854                         neigh_hold(neigh);
 855                         neigh->timer.expires = now + 1;
 856                         add_timer(&neigh->timer);
 857                 } else {
 858                         neigh->nud_state = NUD_FAILED;
 859                         write_unlock_bh(&neigh->lock);
 860
 861                         if (skb)
 862                                 kfree_skb(skb);
 863                         return 1;
 864                 }
 865         } else if (neigh->nud_state & NUD_STALE) {
 866                 NEIGH_PRINTK2("neigh %p is delayed.\n", neigh);
 867                 neigh_hold(neigh);
 868                 neigh->nud_state = NUD_DELAY;
 869                 neigh->timer.expires = jiffies + neigh->parms->delay_probe_time;
 870                 add_timer(&neigh->timer);
 871         }
 872
 873         if (neigh->nud_state == NUD_INCOMPLETE) {
 874                 if (skb) {
 875                         if (skb_queue_len(&neigh->arp_queue) >=
 876                             neigh->parms->queue_len) {
 877                                 struct sk_buff *buff;
 878                                 buff = neigh->arp_queue.next;
 879                                 __skb_unlink(buff, &neigh->arp_queue);
 880                                 kfree_skb(buff);
 881                         }
 882                         __skb_queue_tail(&neigh->arp_queue, skb);
 883                 }
 884                 rc = 1;
 885         }
 886 out_unlock_bh:
 887         write_unlock_bh(&neigh->lock);
 888         return rc;
 889 }
 890
 891 static __inline__ void neigh_update_hhs(struct neighbour *neigh)
 892 {
 893         struct hh_cache *hh;
 894         void (*update)(struct hh_cache*, struct net_device*, unsigned char *) =
 895                 neigh->dev->header_cache_update;
 896
 897         if (update) {
 898                 for (hh = neigh->hh; hh; hh = hh->hh_next) {
 899                         write_lock_bh(&hh->hh_lock);
 900                         update(hh, neigh->dev, neigh->ha);
 901                         write_unlock_bh(&hh->hh_lock);
 902                 }
 903         }
 904 }
 905
 906
 907
 908 /* Generic update routine.
 909    -- lladdr is new lladdr or NULL, if it is not supplied.
 910    -- new    is new state.
 911    -- flags
 912         NEIGH_UPDATE_F_OVERRIDE allows to override existing lladdr,
 913                                 if it is different.
 914         NEIGH_UPDATE_F_WEAK_OVERRIDE will suspect existing "connected"
 915                                 lladdr instead of overriding it
 916                                 if it is different.
 917                                 It also allows to retain current state
 918                                 if lladdr is unchanged.
 919         NEIGH_UPDATE_F_ADMIN    means that the change is administrative.
 920
 921         NEIGH_UPDATE_F_OVERRIDE_ISROUTER allows to override existing
 922                                 NTF_ROUTER flag.
 923         NEIGH_UPDATE_F_ISROUTER indicates if the neighbour is known as
 924                                 a router.
 925
 926    Caller MUST hold reference count on the entry.
 927  */
 928
 929 int neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new,
 930                  u32 flags)
 931 {
 932         u8 old;
 933         int err;
 934 #ifdef CONFIG_ARPD
 935         int notify = 0;
 936 #endif
 937         struct net_device *dev;
 938         int update_isrouter = 0;
 939
 940         write_lock_bh(&neigh->lock);
 941
 942         dev    = neigh->dev;
 943         old    = neigh->nud_state;
 944         err    = -EPERM;
 945
 946         if (!(flags & NEIGH_UPDATE_F_ADMIN) &&
 947             (old & (NUD_NOARP | NUD_PERMANENT)))
 948                 goto out;
 949
 950         if (!(new & NUD_VALID)) {
 951                 neigh_del_timer(neigh);
 952                 if (old & NUD_CONNECTED)
 953                         neigh_suspect(neigh);
 954                 neigh->nud_state = new;
 955                 err = 0;
 956 #ifdef CONFIG_ARPD
 957                 notify = old & NUD_VALID;
 958 #endif
 959                 goto out;
 960         }
 961
 962         /* Compare new lladdr with cached one */
 963         if (!dev->addr_len) {
 964                 /* First case: device needs no address. */
 965                 lladdr = neigh->ha;
 966         } else if (lladdr) {
 967                 /* The second case: if something is already cached
 968                    and a new address is proposed:
 969                    - compare new & old
 970                    - if they are different, check override flag
 971                  */
 972                 if ((old & NUD_VALID) &&
 973                     !memcmp(lladdr, neigh->ha, dev->addr_len))
 974                         lladdr = neigh->ha;
 975         } else {
 976                 /* No address is supplied; if we know something,
 977                    use it, otherwise discard the request.
 978                  */
 979                 err = -EINVAL;
 980                 if (!(old & NUD_VALID))
 981                         goto out;
 982                 lladdr = neigh->ha;
 983         }
 984
 985         if (new & NUD_CONNECTED)
 986                 neigh->confirmed = jiffies;
 987         neigh->updated = jiffies;
 988
 989         /* If entry was valid and address is not changed,
 990            do not change entry state, if new one is STALE.
 991          */
 992         err = 0;
 993         update_isrouter = flags & NEIGH_UPDATE_F_OVERRIDE_ISROUTER;
 994         if (old & NUD_VALID) {
 995                 if (lladdr != neigh->ha && !(flags & NEIGH_UPDATE_F_OVERRIDE)) {
 996                         update_isrouter = 0;
 997                         if ((flags & NEIGH_UPDATE_F_WEAK_OVERRIDE) &&
 998                             (old & NUD_CONNECTED)) {
 999                                 lladdr = neigh->ha;
1000                                 new = NUD_STALE;
1001                         } else
1002                                 goto out;
1003                 } else {
1004                         if (lladdr == neigh->ha && new == NUD_STALE &&
1005                             ((flags & NEIGH_UPDATE_F_WEAK_OVERRIDE) ||
1006                              (old & NUD_CONNECTED))
1007                             )
1008                                 new = old;
1009                 }
1010         }
1011
1012         if (new != old) {
1013                 neigh_del_timer(neigh);
1014                 if (new & NUD_IN_TIMER) {
1015                         neigh_hold(neigh);
1016                         neigh->timer.expires = jiffies +
1017                                                 ((new & NUD_REACHABLE) ?
1018                                                  neigh->parms->reachable_time : 0);
1019                         add_timer(&neigh->timer);
1020                 }
1021                 neigh->nud_state = new;
1022         }
1023
1024         if (lladdr != neigh->ha) {
1025                 memcpy(&neigh->ha, lladdr, dev->addr_len);
1026                 neigh_update_hhs(neigh);
1027                 if (!(new & NUD_CONNECTED))
1028                         neigh->confirmed = jiffies -
1029                                       (neigh->parms->base_reachable_time << 1);
1030 #ifdef CONFIG_ARPD
1031                 notify = 1;
1032 #endif
1033         }
1034         if (new == old)
1035                 goto out;
1036         if (new & NUD_CONNECTED)
1037                 neigh_connect(neigh);
1038         else
1039                 neigh_suspect(neigh);
1040         if (!(old & NUD_VALID)) {
1041                 struct sk_buff *skb;
1042
1043                 /* Again: avoid dead loop if something went wrong */
1044
1045                 while (neigh->nud_state & NUD_VALID &&
1046                        (skb = __skb_dequeue(&neigh->arp_queue)) != NULL) {
1047                         struct neighbour *n1 = neigh;
1048                         write_unlock_bh(&neigh->lock);
1049                         /* On shaper/eql skb->dst->neighbour != neigh :( */
1050                         if (skb->dst && skb->dst->neighbour)
1051                                 n1 = skb->dst->neighbour;
1052                         n1->output(skb);
1053                         write_lock_bh(&neigh->lock);
1054                 }
1055                 skb_queue_purge(&neigh->arp_queue);
1056         }
1057 out:
1058         if (update_isrouter) {
1059                 neigh->flags = (flags & NEIGH_UPDATE_F_ISROUTER) ?
1060                         (neigh->flags | NTF_ROUTER) :
1061                         (neigh->flags & ~NTF_ROUTER);
1062         }
1063         write_unlock_bh(&neigh->lock);
1064 #ifdef CONFIG_ARPD
1065         if (notify && neigh->parms->app_probes)
1066                 neigh_app_notify(neigh);
1067 #endif
1068         return err;
1069 }
1070
1071 struct neighbour *neigh_event_ns(struct neigh_table *tbl,
1072                                  u8 *lladdr, void *saddr,
1073                                  struct net_device *dev)
1074 {
1075         struct neighbour *neigh = __neigh_lookup(tbl, saddr, dev,
1076                                                  lladdr || !dev->addr_len);
1077         if (neigh)
1078                 neigh_update(neigh, lladdr, NUD_STALE,
1079                              NEIGH_UPDATE_F_OVERRIDE);
1080         return neigh;
1081 }
1082
1083 static void neigh_hh_init(struct neighbour *n, struct dst_entry *dst,
1084                           u16 protocol)
1085 {
1086         struct hh_cache *hh;
1087         struct net_device *dev = dst->dev;
1088
1089         for (hh = n->hh; hh; hh = hh->hh_next)
1090                 if (hh->hh_type == protocol)
1091                         break;
1092
1093         if (!hh && (hh = kmalloc(sizeof(*hh), GFP_ATOMIC)) != NULL) {
1094                 memset(hh, 0, sizeof(struct hh_cache));
1095                 rwlock_init(&hh->hh_lock);
1096                 hh->hh_type = protocol;
1097                 atomic_set(&hh->hh_refcnt, 0);
1098                 hh->hh_next = NULL;
1099                 if (dev->hard_header_cache(n, hh)) {
1100                         kfree(hh);
1101                         hh = NULL;
1102                 } else {
1103                         atomic_inc(&hh->hh_refcnt);
1104                         hh->hh_next = n->hh;
1105                         n->hh       = hh;
1106                         if (n->nud_state & NUD_CONNECTED)
1107                                 hh->hh_output = n->ops->hh_output;
1108                         else
1109                                 hh->hh_output = n->ops->output;
1110                 }
1111         }
1112         if (hh) {
1113                 atomic_inc(&hh->hh_refcnt);
1114                 dst->hh = hh;
1115         }
1116 }
1117
1118 /* This function can be used in contexts, where only old dev_queue_xmit
1119    worked, f.e. if you want to override normal output path (eql, shaper),
1120    but resolution is not made yet.
1121  */
1122
1123 int neigh_compat_output(struct sk_buff *skb)
1124 {
1125         struct net_device *dev = skb->dev;
1126
1127         __skb_pull(skb, skb->nh.raw - skb->data);
1128
1129         if (dev->hard_header &&
1130             dev->hard_header(skb, dev, ntohs(skb->protocol), NULL, NULL,
1131                              skb->len) < 0 &&
1132             dev->rebuild_header(skb))
1133                 return 0;
1134
1135         return dev_queue_xmit(skb);
1136 }
1137
1138 /* Slow and careful. */
1139
1140 int neigh_resolve_output(struct sk_buff *skb)
1141 {
1142         struct dst_entry *dst = skb->dst;
1143         struct neighbour *neigh;
1144         int rc = 0;
1145
1146         if (!dst || !(neigh = dst->neighbour))
1147                 goto discard;
1148
1149         __skb_pull(skb, skb->nh.raw - skb->data);
1150
1151         if (!neigh_event_send(neigh, skb)) {
1152                 int err;
1153                 struct net_device *dev = neigh->dev;
1154                 if (dev->hard_header_cache && !dst->hh) {
1155                         write_lock_bh(&neigh->lock);
1156                         if (!dst->hh)
1157                                 neigh_hh_init(neigh, dst, dst->ops->protocol);
1158                         err = dev->hard_header(skb, dev, ntohs(skb->protocol),
1159                                                neigh->ha, NULL, skb->len);
1160                         write_unlock_bh(&neigh->lock);
1161                 } else {
1162                         read_lock_bh(&neigh->lock);
1163                         err = dev->hard_header(skb, dev, ntohs(skb->protocol),
1164                                                neigh->ha, NULL, skb->len);
1165                         read_unlock_bh(&neigh->lock);
1166                 }
1167                 if (err >= 0)
1168                         rc = neigh->ops->queue_xmit(skb);
1169                 else
1170                         goto out_kfree_skb;
1171         }
1172 out:
1173         return rc;
1174 discard:
1175         NEIGH_PRINTK1("neigh_resolve_output: dst=%p neigh=%p\n",
1176                       dst, dst ? dst->neighbour : NULL);
1177 out_kfree_skb:
1178         rc = -EINVAL;
1179         kfree_skb(skb);
1180         goto out;
1181 }
1182
1183 /* As fast as possible without hh cache */
1184
1185 int neigh_connected_output(struct sk_buff *skb)
1186 {
1187         int err;
1188         struct dst_entry *dst = skb->dst;
1189         struct neighbour *neigh = dst->neighbour;
1190         struct net_device *dev = neigh->dev;
1191
1192         __skb_pull(skb, skb->nh.raw - skb->data);
1193
1194         read_lock_bh(&neigh->lock);
1195         err = dev->hard_header(skb, dev, ntohs(skb->protocol),
1196                                neigh->ha, NULL, skb->len);
1197         read_unlock_bh(&neigh->lock);
1198         if (err >= 0)
1199                 err = neigh->ops->queue_xmit(skb);
1200         else {
1201                 err = -EINVAL;
1202                 kfree_skb(skb);
1203         }
1204         return err;
1205 }
1206
1207 static void neigh_proxy_process(unsigned long arg)
1208 {
1209         struct neigh_table *tbl = (struct neigh_table *)arg;
1210         long sched_next = 0;
1211         unsigned long now = jiffies;
1212         struct sk_buff *skb;
1213
1214         spin_lock(&tbl->proxy_queue.lock);
1215
1216         skb = tbl->proxy_queue.next;
1217
1218         while (skb != (struct sk_buff *)&tbl->proxy_queue) {
1219                 struct sk_buff *back = skb;
1220                 long tdif = NEIGH_CB(back)->sched_next - now;
1221
1222                 skb = skb->next;
1223                 if (tdif <= 0) {
1224                         struct net_device *dev = back->dev;
1225                         __skb_unlink(back, &tbl->proxy_queue);
1226                         if (tbl->proxy_redo && netif_running(dev))
1227                                 tbl->proxy_redo(back);
1228                         else
1229                                 kfree_skb(back);
1230
1231                         dev_put(dev);
1232                 } else if (!sched_next || tdif < sched_next)
1233                         sched_next = tdif;
1234         }
1235         del_timer(&tbl->proxy_timer);
1236         if (sched_next)
1237                 mod_timer(&tbl->proxy_timer, jiffies + sched_next);
1238         spin_unlock(&tbl->proxy_queue.lock);
1239 }
1240
1241 void pneigh_enqueue(struct neigh_table *tbl, struct neigh_parms *p,
1242                     struct sk_buff *skb)
1243 {
1244         unsigned long now = jiffies;
1245         unsigned long sched_next = now + (net_random() % p->proxy_delay);
1246
1247         if (tbl->proxy_queue.qlen > p->proxy_qlen) {
1248                 kfree_skb(skb);
1249                 return;
1250         }
1251
1252         NEIGH_CB(skb)->sched_next = sched_next;
1253         NEIGH_CB(skb)->flags |= LOCALLY_ENQUEUED;
1254
1255         spin_lock(&tbl->proxy_queue.lock);
1256         if (del_timer(&tbl->proxy_timer)) {
1257                 if (time_before(tbl->proxy_timer.expires, sched_next))
1258                         sched_next = tbl->proxy_timer.expires;
1259         }
1260         dst_release(skb->dst);
1261         skb->dst = NULL;
1262         dev_hold(skb->dev);
1263         __skb_queue_tail(&tbl->proxy_queue, skb);
1264         mod_timer(&tbl->proxy_timer, sched_next);
1265         spin_unlock(&tbl->proxy_queue.lock);
1266 }
1267
1268
1269 struct neigh_parms *neigh_parms_alloc(struct net_device *dev,
1270                                       struct neigh_table *tbl)
1271 {
1272         struct neigh_parms *p = kmalloc(sizeof(*p), GFP_KERNEL);
1273
1274         if (p) {
1275                 memcpy(p, &tbl->parms, sizeof(*p));
1276                 p->tbl            = tbl;
1277                 atomic_set(&p->refcnt, 1);
1278                 INIT_RCU_HEAD(&p->rcu_head);
1279                 p->reachable_time =
1280                                 neigh_rand_reach_time(p->base_reachable_time);
1281                 if (dev) {
1282                         if (dev->neigh_setup && dev->neigh_setup(dev, p)) {
1283                                 kfree(p);
1284                                 return NULL;
1285                         }
1286
1287                         dev_hold(dev);
1288                         p->dev = dev;
1289                 }
1290                 p->sysctl_table = NULL;
1291                 write_lock_bh(&tbl->lock);
1292                 p->next         = tbl->parms.next;
1293                 tbl->parms.next = p;
1294                 write_unlock_bh(&tbl->lock);
1295         }
1296         return p;
1297 }
1298
1299 static void neigh_rcu_free_parms(struct rcu_head *head)
1300 {
1301         struct neigh_parms *parms =
1302                 container_of(head, struct neigh_parms, rcu_head);
1303
1304         neigh_parms_put(parms);
1305 }
1306
1307 void neigh_parms_release(struct neigh_table *tbl, struct neigh_parms *parms)
1308 {
1309         struct neigh_parms **p;
1310
1311         if (!parms || parms == &tbl->parms)
1312                 return;
1313         write_lock_bh(&tbl->lock);
1314         for (p = &tbl->parms.next; *p; p = &(*p)->next) {
1315                 if (*p == parms) {
1316                         *p = parms->next;
1317                         parms->dead = 1;
1318                         write_unlock_bh(&tbl->lock);
1319                         if (parms->dev)
1320                                 dev_put(parms->dev);
1321                         call_rcu(&parms->rcu_head, neigh_rcu_free_parms);
1322                         return;
1323                 }
1324         }
1325         write_unlock_bh(&tbl->lock);
1326         NEIGH_PRINTK1("neigh_parms_release: not found\n");
1327 }
1328
1329 void neigh_parms_destroy(struct neigh_parms *parms)
1330 {
1331         kfree(parms);
1332 }
1333
1334
1335 void neigh_table_init(struct neigh_table *tbl)
1336 {
1337         unsigned long now = jiffies;
1338         unsigned long phsize;
1339
1340         atomic_set(&tbl->parms.refcnt, 1);
1341         INIT_RCU_HEAD(&tbl->parms.rcu_head);
1342         tbl->parms.reachable_time =
1343                           neigh_rand_reach_time(tbl->parms.base_reachable_time);
1344
1345         if (!tbl->kmem_cachep)
1346                 tbl->kmem_cachep = kmem_cache_create(tbl->id,
1347                                                      tbl->entry_size,
1348                                                      0, SLAB_HWCACHE_ALIGN,
1349                                                      NULL, NULL);
1350
1351         if (!tbl->kmem_cachep)
1352                 panic("cannot create neighbour cache");
1353
1354         tbl->stats = alloc_percpu(struct neigh_statistics);
1355         if (!tbl->stats)
1356                 panic("cannot create neighbour cache statistics");
1357
1358 #ifdef CONFIG_PROC_FS
1359         tbl->pde = create_proc_entry(tbl->id, 0, proc_net_stat);
1360         if (!tbl->pde)
1361                 panic("cannot create neighbour proc dir entry");
1362         tbl->pde->proc_fops = &neigh_stat_seq_fops;
1363         tbl->pde->data = tbl;
1364 #endif
1365
1366         tbl->hash_mask = 1;
1367         tbl->hash_buckets = neigh_hash_alloc(tbl->hash_mask + 1);
1368
1369         phsize = (PNEIGH_HASHMASK + 1) * sizeof(struct pneigh_entry *);
1370         tbl->phash_buckets = kmalloc(phsize, GFP_KERNEL);
1371
1372         if (!tbl->hash_buckets || !tbl->phash_buckets)
1373                 panic("cannot allocate neighbour cache hashes");
1374
1375         memset(tbl->phash_buckets, 0, phsize);
1376
1377         get_random_bytes(&tbl->hash_rnd, sizeof(tbl->hash_rnd));
1378
1379         rwlock_init(&tbl->lock);
1380         init_timer(&tbl->gc_timer);
1381         tbl->gc_timer.data     = (unsigned long)tbl;
1382         tbl->gc_timer.function = neigh_periodic_timer;
1383         tbl->gc_timer.expires  = now + 1;
1384         add_timer(&tbl->gc_timer);
1385
1386         init_timer(&tbl->proxy_timer);
1387         tbl->proxy_timer.data     = (unsigned long)tbl;
1388         tbl->proxy_timer.function = neigh_proxy_process;
1389         skb_queue_head_init(&tbl->proxy_queue);
1390
1391         tbl->last_flush = now;
1392         tbl->last_rand  = now + tbl->parms.reachable_time * 20;
1393         write_lock(&neigh_tbl_lock);
1394         tbl->next       = neigh_tables;
1395         neigh_tables    = tbl;
1396         write_unlock(&neigh_tbl_lock);
1397 }
1398
1399 int neigh_table_clear(struct neigh_table *tbl)
1400 {
1401         struct neigh_table **tp;
1402
1403         /* It is not clean... Fix it to unload IPv6 module safely */
1404         del_timer_sync(&tbl->gc_timer);
1405         del_timer_sync(&tbl->proxy_timer);
1406         pneigh_queue_purge(&tbl->proxy_queue);
1407         neigh_ifdown(tbl, NULL);
1408         if (atomic_read(&tbl->entries))
1409                 printk(KERN_CRIT "neighbour leakage\n");
1410         write_lock(&neigh_tbl_lock);
1411         for (tp = &neigh_tables; *tp; tp = &(*tp)->next) {
1412                 if (*tp == tbl) {
1413                         *tp = tbl->next;
1414                         break;
1415                 }
1416         }
1417         write_unlock(&neigh_tbl_lock);
1418
1419         neigh_hash_free(tbl->hash_buckets, tbl->hash_mask + 1);
1420         tbl->hash_buckets = NULL;
1421
1422         kfree(tbl->phash_buckets);
1423         tbl->phash_buckets = NULL;
1424
1425         return 0;
1426 }
1427
1428 int neigh_delete(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
1429 {
1430         struct ndmsg *ndm = NLMSG_DATA(nlh);
1431         struct rtattr **nda = arg;
1432         struct neigh_table *tbl;
1433         struct net_device *dev = NULL;
1434         int err = -ENODEV;
1435
1436         if (ndm->ndm_ifindex &&
1437             (dev = dev_get_by_index(ndm->ndm_ifindex)) == NULL)
1438                 goto out;
1439
1440         read_lock(&neigh_tbl_lock);
1441         for (tbl = neigh_tables; tbl; tbl = tbl->next) {
1442                 struct rtattr *dst_attr = nda[NDA_DST - 1];
1443                 struct neighbour *n;
1444
1445                 if (tbl->family != ndm->ndm_family)
1446                         continue;
1447                 read_unlock(&neigh_tbl_lock);
1448
1449                 err = -EINVAL;
1450                 if (!dst_attr || RTA_PAYLOAD(dst_attr) < tbl->key_len)
1451                         goto out_dev_put;
1452
1453                 if (ndm->ndm_flags & NTF_PROXY) {
1454                         err = pneigh_delete(tbl, RTA_DATA(dst_attr), dev);
1455                         goto out_dev_put;
1456                 }
1457
1458                 if (!dev)
1459                         goto out;
1460
1461                 n = neigh_lookup(tbl, RTA_DATA(dst_attr), dev);
1462                 if (n) {
1463                         err = neigh_update(n, NULL, NUD_FAILED,
1464                                            NEIGH_UPDATE_F_OVERRIDE|
1465                                            NEIGH_UPDATE_F_ADMIN);
1466                         neigh_release(n);
1467                 }
1468                 goto out_dev_put;
1469         }
1470         read_unlock(&neigh_tbl_lock);
1471         err = -EADDRNOTAVAIL;
1472 out_dev_put:
1473         if (dev)
1474                 dev_put(dev);
1475 out:
1476         return err;
1477 }
1478
1479 int neigh_add(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
1480 {
1481         struct ndmsg *ndm = NLMSG_DATA(nlh);
1482         struct rtattr **nda = arg;
1483         struct neigh_table *tbl;
1484         struct net_device *dev = NULL;
1485         int err = -ENODEV;
1486
1487         if (ndm->ndm_ifindex &&
1488             (dev = dev_get_by_index(ndm->ndm_ifindex)) == NULL)
1489                 goto out;
1490
1491         read_lock(&neigh_tbl_lock);
1492         for (tbl = neigh_tables; tbl; tbl = tbl->next) {
1493                 struct rtattr *lladdr_attr = nda[NDA_LLADDR - 1];
1494                 struct rtattr *dst_attr = nda[NDA_DST - 1];
1495                 int override = 1;
1496                 struct neighbour *n;
1497
1498                 if (tbl->family != ndm->ndm_family)
1499                         continue;
1500                 read_unlock(&neigh_tbl_lock);
1501
1502                 err = -EINVAL;
1503                 if (!dst_attr || RTA_PAYLOAD(dst_attr) < tbl->key_len)
1504                         goto out_dev_put;
1505
1506                 if (ndm->ndm_flags & NTF_PROXY) {
1507                         err = -ENOBUFS;
1508                         if (pneigh_lookup(tbl, RTA_DATA(dst_attr), dev, 1))
1509                                 err = 0;
1510                         goto out_dev_put;
1511                 }
1512
1513                 err = -EINVAL;
1514                 if (!dev)
1515                         goto out;
1516                 if (lladdr_attr && RTA_PAYLOAD(lladdr_attr) < dev->addr_len)
1517                         goto out_dev_put;
1518
1519                 n = neigh_lookup(tbl, RTA_DATA(dst_attr), dev);
1520                 if (n) {
1521                         if (nlh->nlmsg_flags & NLM_F_EXCL) {
1522                                 err = -EEXIST;
1523                                 neigh_release(n);
1524                                 goto out_dev_put;
1525                         }
1526
1527                         override = nlh->nlmsg_flags & NLM_F_REPLACE;
1528                 } else if (!(nlh->nlmsg_flags & NLM_F_CREATE)) {
1529                         err = -ENOENT;
1530                         goto out_dev_put;
1531                 } else {
1532                         n = __neigh_lookup_errno(tbl, RTA_DATA(dst_attr), dev);
1533                         if (IS_ERR(n)) {
1534                                 err = PTR_ERR(n);
1535                                 goto out_dev_put;
1536                         }
1537                 }
1538
1539                 err = neigh_update(n,
1540                                    lladdr_attr ? RTA_DATA(lladdr_attr) : NULL,
1541                                    ndm->ndm_state,
1542                                    (override ? NEIGH_UPDATE_F_OVERRIDE : 0) |
1543                                    NEIGH_UPDATE_F_ADMIN);
1544
1545                 neigh_release(n);
1546                 goto out_dev_put;
1547         }
1548
1549         read_unlock(&neigh_tbl_lock);
1550         err = -EADDRNOTAVAIL;
1551 out_dev_put:
1552         if (dev)
1553                 dev_put(dev);
1554 out:
1555         return err;
1556 }
1557
1558 static int neightbl_fill_parms(struct sk_buff *skb, struct neigh_parms *parms)
1559 {
1560         struct rtattr *nest = NULL;
1561
1562         nest = RTA_NEST(skb, NDTA_PARMS);
1563
1564         if (parms->dev)
1565                 RTA_PUT_U32(skb, NDTPA_IFINDEX, parms->dev->ifindex);
1566
1567         RTA_PUT_U32(skb, NDTPA_REFCNT, atomic_read(&parms->refcnt));
1568         RTA_PUT_U32(skb, NDTPA_QUEUE_LEN, parms->queue_len);
1569         RTA_PUT_U32(skb, NDTPA_PROXY_QLEN, parms->proxy_qlen);
1570         RTA_PUT_U32(skb, NDTPA_APP_PROBES, parms->app_probes);
1571         RTA_PUT_U32(skb, NDTPA_UCAST_PROBES, parms->ucast_probes);
1572         RTA_PUT_U32(skb, NDTPA_MCAST_PROBES, parms->mcast_probes);
1573         RTA_PUT_MSECS(skb, NDTPA_REACHABLE_TIME, parms->reachable_time);
1574         RTA_PUT_MSECS(skb, NDTPA_BASE_REACHABLE_TIME,
1575                       parms->base_reachable_time);
1576         RTA_PUT_MSECS(skb, NDTPA_GC_STALETIME, parms->gc_staletime);
1577         RTA_PUT_MSECS(skb, NDTPA_DELAY_PROBE_TIME, parms->delay_probe_time);
1578         RTA_PUT_MSECS(skb, NDTPA_RETRANS_TIME, parms->retrans_time);
1579         RTA_PUT_MSECS(skb, NDTPA_ANYCAST_DELAY, parms->anycast_delay);
1580         RTA_PUT_MSECS(skb, NDTPA_PROXY_DELAY, parms->proxy_delay);
1581         RTA_PUT_MSECS(skb, NDTPA_LOCKTIME, parms->locktime);
1582
1583         return RTA_NEST_END(skb, nest);
1584
1585 rtattr_failure:
1586         return RTA_NEST_CANCEL(skb, nest);
1587 }
1588
1589 static int neightbl_fill_info(struct neigh_table *tbl, struct sk_buff *skb,
1590                               struct netlink_callback *cb)
1591 {
1592         struct nlmsghdr *nlh;
1593         struct ndtmsg *ndtmsg;
1594
1595         nlh = NLMSG_NEW_ANSWER(skb, cb, RTM_NEWNEIGHTBL, sizeof(struct ndtmsg),
1596                                NLM_F_MULTI);
1597
1598         ndtmsg = NLMSG_DATA(nlh);
1599
1600         read_lock_bh(&tbl->lock);
1601         ndtmsg->ndtm_family = tbl->family;
1602         ndtmsg->ndtm_pad1   = 0;
1603         ndtmsg->ndtm_pad2   = 0;
1604
1605         RTA_PUT_STRING(skb, NDTA_NAME, tbl->id);
1606         RTA_PUT_MSECS(skb, NDTA_GC_INTERVAL, tbl->gc_interval);
1607         RTA_PUT_U32(skb, NDTA_THRESH1, tbl->gc_thresh1);
1608         RTA_PUT_U32(skb, NDTA_THRESH2, tbl->gc_thresh2);
1609         RTA_PUT_U32(skb, NDTA_THRESH3, tbl->gc_thresh3);
1610
1611         {
1612                 unsigned long now = jiffies;
1613                 unsigned int flush_delta = now - tbl->last_flush;
1614                 unsigned int rand_delta = now - tbl->last_rand;
1615
1616                 struct ndt_config ndc = {
1617                         .ndtc_key_len           = tbl->key_len,
1618                         .ndtc_entry_size        = tbl->entry_size,
1619                         .ndtc_entries           = atomic_read(&tbl->entries),
1620                         .ndtc_last_flush        = jiffies_to_msecs(flush_delta),
1621                         .ndtc_last_rand         = jiffies_to_msecs(rand_delta),
1622                         .ndtc_hash_rnd          = tbl->hash_rnd,
1623                         .ndtc_hash_mask         = tbl->hash_mask,
1624                         .ndtc_hash_chain_gc     = tbl->hash_chain_gc,
1625                         .ndtc_proxy_qlen        = tbl->proxy_queue.qlen,
1626                 };
1627
1628                 RTA_PUT(skb, NDTA_CONFIG, sizeof(ndc), &ndc);
1629         }
1630
1631         {
1632                 int cpu;
1633                 struct ndt_stats ndst;
1634
1635                 memset(&ndst, 0, sizeof(ndst));
1636
1637                 for (cpu = 0; cpu < NR_CPUS; cpu++) {
1638                         struct neigh_statistics *st;
1639
1640                         if (!cpu_possible(cpu))
1641                                 continue;
1642
1643                         st = per_cpu_ptr(tbl->stats, cpu);
1644                         ndst.ndts_allocs                += st->allocs;
1645                         ndst.ndts_destroys              += st->destroys;
1646                         ndst.ndts_hash_grows            += st->hash_grows;
1647                         ndst.ndts_res_failed            += st->res_failed;
1648                         ndst.ndts_lookups               += st->lookups;
1649                         ndst.ndts_hits                  += st->hits;
1650                         ndst.ndts_rcv_probes_mcast      += st->rcv_probes_mcast;
1651                         ndst.ndts_rcv_probes_ucast      += st->rcv_probes_ucast;
1652                         ndst.ndts_periodic_gc_runs      += st->periodic_gc_runs;
1653                         ndst.ndts_forced_gc_runs        += st->forced_gc_runs;
1654                 }
1655
1656                 RTA_PUT(skb, NDTA_STATS, sizeof(ndst), &ndst);
1657         }
1658
1659         BUG_ON(tbl->parms.dev);
1660         if (neightbl_fill_parms(skb, &tbl->parms) < 0)
1661                 goto rtattr_failure;
1662
1663         read_unlock_bh(&tbl->lock);
1664         return NLMSG_END(skb, nlh);
1665
1666 rtattr_failure:
1667         read_unlock_bh(&tbl->lock);
1668         return NLMSG_CANCEL(skb, nlh);
1669
1670 nlmsg_failure:
1671         return -1;
1672 }
1673
1674 static int neightbl_fill_param_info(struct neigh_table *tbl,
1675                                     struct neigh_parms *parms,
1676                                     struct sk_buff *skb,
1677                                     struct netlink_callback *cb)
1678 {
1679         struct ndtmsg *ndtmsg;
1680         struct nlmsghdr *nlh;
1681
1682         nlh = NLMSG_NEW_ANSWER(skb, cb, RTM_NEWNEIGHTBL, sizeof(struct ndtmsg),
1683                                NLM_F_MULTI);
1684
1685         ndtmsg = NLMSG_DATA(nlh);
1686
1687         read_lock_bh(&tbl->lock);
1688         ndtmsg->ndtm_family = tbl->family;
1689         ndtmsg->ndtm_pad1   = 0;
1690         ndtmsg->ndtm_pad2   = 0;
1691         RTA_PUT_STRING(skb, NDTA_NAME, tbl->id);
1692
1693         if (neightbl_fill_parms(skb, parms) < 0)
1694                 goto rtattr_failure;
1695
1696         read_unlock_bh(&tbl->lock);
1697         return NLMSG_END(skb, nlh);
1698
1699 rtattr_failure:
1700         read_unlock_bh(&tbl->lock);
1701         return NLMSG_CANCEL(skb, nlh);
1702
1703 nlmsg_failure:
1704         return -1;
1705 }
1706
1707 static inline struct neigh_parms *lookup_neigh_params(struct neigh_table *tbl,
1708                                                       int ifindex)
1709 {
1710         struct neigh_parms *p;
1711
1712         for (p = &tbl->parms; p; p = p->next)
1713                 if ((p->dev && p->dev->ifindex == ifindex) ||
1714                     (!p->dev && !ifindex))
1715                         return p;
1716
1717         return NULL;
1718 }
1719
1720 int neightbl_set(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
1721 {
1722         struct neigh_table *tbl;
1723         struct ndtmsg *ndtmsg = NLMSG_DATA(nlh);
1724         struct rtattr **tb = arg;
1725         int err = -EINVAL;
1726
1727         if (!tb[NDTA_NAME - 1] || !RTA_PAYLOAD(tb[NDTA_NAME - 1]))
1728                 return -EINVAL;
1729
1730         read_lock(&neigh_tbl_lock);
1731         for (tbl = neigh_tables; tbl; tbl = tbl->next) {
1732                 if (ndtmsg->ndtm_family && tbl->family != ndtmsg->ndtm_family)
1733                         continue;
1734
1735                 if (!rtattr_strcmp(tb[NDTA_NAME - 1], tbl->id))
1736                         break;
1737         }
1738
1739         if (tbl == NULL) {
1740                 err = -ENOENT;
1741                 goto errout;
1742         }
1743
1744         /*
1745          * We acquire tbl->lock to be nice to the periodic timers and
1746          * make sure they always see a consistent set of values.
1747          */
1748         write_lock_bh(&tbl->lock);
1749
1750         if (tb[NDTA_THRESH1 - 1])
1751                 tbl->gc_thresh1 = RTA_GET_U32(tb[NDTA_THRESH1 - 1]);
1752
1753         if (tb[NDTA_THRESH2 - 1])
1754                 tbl->gc_thresh2 = RTA_GET_U32(tb[NDTA_THRESH2 - 1]);
1755
1756         if (tb[NDTA_THRESH3 - 1])
1757                 tbl->gc_thresh3 = RTA_GET_U32(tb[NDTA_THRESH3 - 1]);
1758
1759         if (tb[NDTA_GC_INTERVAL - 1])
1760                 tbl->gc_interval = RTA_GET_MSECS(tb[NDTA_GC_INTERVAL - 1]);
1761
1762         if (tb[NDTA_PARMS - 1]) {
1763                 struct rtattr *tbp[NDTPA_MAX];
1764                 struct neigh_parms *p;
1765                 u32 ifindex = 0;
1766
1767                 if (rtattr_parse_nested(tbp, NDTPA_MAX, tb[NDTA_PARMS - 1]) < 0)
1768                         goto rtattr_failure;
1769
1770                 if (tbp[NDTPA_IFINDEX - 1])
1771                         ifindex = RTA_GET_U32(tbp[NDTPA_IFINDEX - 1]);
1772
1773                 p = lookup_neigh_params(tbl, ifindex);
1774                 if (p == NULL) {
1775                         err = -ENOENT;
1776                         goto rtattr_failure;
1777                 }
1778
1779                 if (tbp[NDTPA_QUEUE_LEN - 1])
1780                         p->queue_len = RTA_GET_U32(tbp[NDTPA_QUEUE_LEN - 1]);
1781
1782                 if (tbp[NDTPA_PROXY_QLEN - 1])
1783                         p->proxy_qlen = RTA_GET_U32(tbp[NDTPA_PROXY_QLEN - 1]);
1784
1785                 if (tbp[NDTPA_APP_PROBES - 1])
1786                         p->app_probes = RTA_GET_U32(tbp[NDTPA_APP_PROBES - 1]);
1787
1788                 if (tbp[NDTPA_UCAST_PROBES - 1])
1789                         p->ucast_probes =
1790                            RTA_GET_U32(tbp[NDTPA_UCAST_PROBES - 1]);
1791
1792                 if (tbp[NDTPA_MCAST_PROBES - 1])
1793                         p->mcast_probes =
1794                            RTA_GET_U32(tbp[NDTPA_MCAST_PROBES - 1]);
1795
1796                 if (tbp[NDTPA_BASE_REACHABLE_TIME - 1])
1797                         p->base_reachable_time =
1798                            RTA_GET_MSECS(tbp[NDTPA_BASE_REACHABLE_TIME - 1]);
1799
1800                 if (tbp[NDTPA_GC_STALETIME - 1])
1801                         p->gc_staletime =
1802                            RTA_GET_MSECS(tbp[NDTPA_GC_STALETIME - 1]);
1803
1804                 if (tbp[NDTPA_DELAY_PROBE_TIME - 1])
1805                         p->delay_probe_time =
1806                            RTA_GET_MSECS(tbp[NDTPA_DELAY_PROBE_TIME - 1]);
1807
1808                 if (tbp[NDTPA_RETRANS_TIME - 1])
1809                         p->retrans_time =
1810                            RTA_GET_MSECS(tbp[NDTPA_RETRANS_TIME - 1]);
1811
1812                 if (tbp[NDTPA_ANYCAST_DELAY - 1])
1813                         p->anycast_delay =
1814                            RTA_GET_MSECS(tbp[NDTPA_ANYCAST_DELAY - 1]);
1815
1816                 if (tbp[NDTPA_PROXY_DELAY - 1])
1817                         p->proxy_delay =
1818                            RTA_GET_MSECS(tbp[NDTPA_PROXY_DELAY - 1]);
1819
1820                 if (tbp[NDTPA_LOCKTIME - 1])
1821                         p->locktime = RTA_GET_MSECS(tbp[NDTPA_LOCKTIME - 1]);
1822         }
1823
1824         err = 0;
1825
1826 rtattr_failure:
1827         write_unlock_bh(&tbl->lock);
1828 errout:
1829         read_unlock(&neigh_tbl_lock);
1830         return err;
1831 }
1832
1833 int neightbl_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
1834 {
1835         int idx, family;
1836         int s_idx = cb->args[0];
1837         struct neigh_table *tbl;
1838
1839         family = ((struct rtgenmsg *)NLMSG_DATA(cb->nlh))->rtgen_family;
1840
1841         read_lock(&neigh_tbl_lock);
1842         for (tbl = neigh_tables, idx = 0; tbl; tbl = tbl->next) {
1843                 struct neigh_parms *p;
1844
1845                 if (idx < s_idx || (family && tbl->family != family))
1846                         continue;
1847
1848                 if (neightbl_fill_info(tbl, skb, cb) <= 0)
1849                         break;
1850
1851                 for (++idx, p = tbl->parms.next; p; p = p->next, idx++) {
1852                         if (idx < s_idx)
1853                                 continue;
1854
1855                         if (neightbl_fill_param_info(tbl, p, skb, cb) <= 0)
1856                                 goto out;
1857                 }
1858
1859         }
1860 out:
1861         read_unlock(&neigh_tbl_lock);
1862         cb->args[0] = idx;
1863
1864         return skb->len;
1865 }
1866
1867 static int neigh_fill_info(struct sk_buff *skb, struct neighbour *n,
1868                            u32 pid, u32 seq, int event, unsigned int flags)
1869 {
1870         unsigned long now = jiffies;
1871         unsigned char *b = skb->tail;
1872         struct nda_cacheinfo ci;
1873         int locked = 0;
1874         u32 probes;
1875         struct nlmsghdr *nlh = NLMSG_NEW(skb, pid, seq, event,
1876                                          sizeof(struct ndmsg), flags);
1877         struct ndmsg *ndm = NLMSG_DATA(nlh);
1878
1879         ndm->ndm_family  = n->ops->family;
1880         ndm->ndm_pad1    = 0;
1881         ndm->ndm_pad2    = 0;
1882         ndm->ndm_flags   = n->flags;
1883         ndm->ndm_type    = n->type;
1884         ndm->ndm_ifindex = n->dev->ifindex;
1885         RTA_PUT(skb, NDA_DST, n->tbl->key_len, n->primary_key);
1886         read_lock_bh(&n->lock);
1887         locked           = 1;
1888         ndm->ndm_state   = n->nud_state;
1889         if (n->nud_state & NUD_VALID)
1890                 RTA_PUT(skb, NDA_LLADDR, n->dev->addr_len, n->ha);
1891         ci.ndm_used      = now - n->used;
1892         ci.ndm_confirmed = now - n->confirmed;
1893         ci.ndm_updated   = now - n->updated;
1894         ci.ndm_refcnt    = atomic_read(&n->refcnt) - 1;
1895         probes = atomic_read(&n->probes);
1896         read_unlock_bh(&n->lock);
1897         locked           = 0;
1898         RTA_PUT(skb, NDA_CACHEINFO, sizeof(ci), &ci);
1899         RTA_PUT(skb, NDA_PROBES, sizeof(probes), &probes);
1900         nlh->nlmsg_len   = skb->tail - b;
1901         return skb->len;
1902
1903 nlmsg_failure:
1904 rtattr_failure:
1905         if (locked)
1906                 read_unlock_bh(&n->lock);
1907         skb_trim(skb, b - skb->data);
1908         return -1;
1909 }
1910
1911
1912 static int neigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb,
1913                             struct netlink_callback *cb)
1914 {
1915         struct neighbour *n;
1916         int rc, h, s_h = cb->args[1];
1917         int idx, s_idx = idx = cb->args[2];
1918
1919         for (h = 0; h <= tbl->hash_mask; h++) {
1920                 if (h < s_h)
1921                         continue;
1922                 if (h > s_h)
1923                         s_idx = 0;
1924                 read_lock_bh(&tbl->lock);
1925                 for (n = tbl->hash_buckets[h], idx = 0; n; n = n->next, idx++) {
1926                         if (idx < s_idx)
1927                                 continue;
1928                         if (neigh_fill_info(skb, n, NETLINK_CB(cb->skb).pid,
1929                                             cb->nlh->nlmsg_seq,
1930                                             RTM_NEWNEIGH,
1931                                             NLM_F_MULTI) <= 0) {
1932                                 read_unlock_bh(&tbl->lock);
1933                                 rc = -1;
1934                                 goto out;
1935                         }
1936                 }
1937                 read_unlock_bh(&tbl->lock);
1938         }
1939         rc = skb->len;
1940 out:
1941         cb->args[1] = h;
1942         cb->args[2] = idx;
1943         return rc;
1944 }
1945
1946 int neigh_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
1947 {
1948         struct neigh_table *tbl;
1949         int t, family, s_t;
1950
1951         read_lock(&neigh_tbl_lock);
1952         family = ((struct rtgenmsg *)NLMSG_DATA(cb->nlh))->rtgen_family;
1953         s_t = cb->args[0];
1954
1955         for (tbl = neigh_tables, t = 0; tbl; tbl = tbl->next, t++) {
1956                 if (t < s_t || (family && tbl->family != family))
1957                         continue;
1958                 if (t > s_t)
1959                         memset(&cb->args[1], 0, sizeof(cb->args) -
1960                                                 sizeof(cb->args[0]));
1961                 if (neigh_dump_table(tbl, skb, cb) < 0)
1962                         break;
1963         }
1964         read_unlock(&neigh_tbl_lock);
1965
1966         cb->args[0] = t;
1967         return skb->len;
1968 }
1969
1970 void neigh_for_each(struct neigh_table *tbl, void (*cb)(struct neighbour *, void *), void *cookie)
1971 {
1972         int chain;
1973
1974         read_lock_bh(&tbl->lock);
1975         for (chain = 0; chain <= tbl->hash_mask; chain++) {
1976                 struct neighbour *n;
1977
1978                 for (n = tbl->hash_buckets[chain]; n; n = n->next)
1979                         cb(n, cookie);
1980         }
1981         read_unlock_bh(&tbl->lock);
1982 }
1983 EXPORT_SYMBOL(neigh_for_each);
1984
1985 /* The tbl->lock must be held as a writer and BH disabled. */
1986 void __neigh_for_each_release(struct neigh_table *tbl,
1987                               int (*cb)(struct neighbour *))
1988 {
1989         int chain;
1990
1991         for (chain = 0; chain <= tbl->hash_mask; chain++) {
1992                 struct neighbour *n, **np;
1993
1994                 np = &tbl->hash_buckets[chain];
1995                 while ((n = *np) != NULL) {
1996                         int release;
1997
1998                         write_lock(&n->lock);
1999                         release = cb(n);
2000                         if (release) {
2001                                 *np = n->next;
2002                                 n->dead = 1;
2003                         } else
2004                                 np = &n->next;
2005                         write_unlock(&n->lock);
2006                         if (release)
2007                                 neigh_release(n);
2008                 }
2009         }
2010 }
2011 EXPORT_SYMBOL(__neigh_for_each_release);
2012
2013 #ifdef CONFIG_PROC_FS
2014
2015 static struct neighbour *neigh_get_first(struct seq_file *seq)
2016 {
2017         struct neigh_seq_state *state = seq->private;
2018         struct neigh_table *tbl = state->tbl;
2019         struct neighbour *n = NULL;
2020         int bucket = state->bucket;
2021
2022         state->flags &= ~NEIGH_SEQ_IS_PNEIGH;
2023         for (bucket = 0; bucket <= tbl->hash_mask; bucket++) {
2024                 n = tbl->hash_buckets[bucket];
2025
2026                 while (n) {
2027                         if (state->neigh_sub_iter) {
2028                                 loff_t fakep = 0;
2029                                 void *v;
2030
2031                                 v = state->neigh_sub_iter(state, n, &fakep);
2032                                 if (!v)
2033                                         goto next;
2034                         }
2035                         if (!(state->flags & NEIGH_SEQ_SKIP_NOARP))
2036                                 break;
2037                         if (n->nud_state & ~NUD_NOARP)
2038                                 break;
2039                 next:
2040                         n = n->next;
2041                 }
2042
2043                 if (n)
2044                         break;
2045         }
2046         state->bucket = bucket;
2047
2048         return n;
2049 }
2050
2051 static struct neighbour *neigh_get_next(struct seq_file *seq,
2052                                         struct neighbour *n,
2053                                         loff_t *pos)
2054 {
2055         struct neigh_seq_state *state = seq->private;
2056         struct neigh_table *tbl = state->tbl;
2057
2058         if (state->neigh_sub_iter) {
2059                 void *v = state->neigh_sub_iter(state, n, pos);
2060                 if (v)
2061                         return n;
2062         }
2063         n = n->next;
2064
2065         while (1) {
2066                 while (n) {
2067                         if (state->neigh_sub_iter) {
2068                                 void *v = state->neigh_sub_iter(state, n, pos);
2069                                 if (v)
2070                                         return n;
2071                                 goto next;
2072                         }
2073                         if (!(state->flags & NEIGH_SEQ_SKIP_NOARP))
2074                                 break;
2075
2076                         if (n->nud_state & ~NUD_NOARP)
2077                                 break;
2078                 next:
2079                         n = n->next;
2080                 }
2081
2082                 if (n)
2083                         break;
2084
2085                 if (++state->bucket > tbl->hash_mask)
2086                         break;
2087
2088                 n = tbl->hash_buckets[state->bucket];
2089         }
2090
2091         if (n && pos)
2092                 --(*pos);
2093         return n;
2094 }
2095
2096 static struct neighbour *neigh_get_idx(struct seq_file *seq, loff_t *pos)
2097 {
2098         struct neighbour *n = neigh_get_first(seq);
2099
2100         if (n) {
2101                 while (*pos) {
2102                         n = neigh_get_next(seq, n, pos);
2103                         if (!n)
2104                                 break;
2105                 }
2106         }
2107         return *pos ? NULL : n;
2108 }
2109
2110 static struct pneigh_entry *pneigh_get_first(struct seq_file *seq)
2111 {
2112         struct neigh_seq_state *state = seq->private;
2113         struct neigh_table *tbl = state->tbl;
2114         struct pneigh_entry *pn = NULL;
2115         int bucket = state->bucket;
2116
2117         state->flags |= NEIGH_SEQ_IS_PNEIGH;
2118         for (bucket = 0; bucket <= PNEIGH_HASHMASK; bucket++) {
2119                 pn = tbl->phash_buckets[bucket];
2120                 if (pn)
2121                         break;
2122         }
2123         state->bucket = bucket;
2124
2125         return pn;
2126 }
2127
2128 static struct pneigh_entry *pneigh_get_next(struct seq_file *seq,
2129                                             struct pneigh_entry *pn,
2130                                             loff_t *pos)
2131 {
2132         struct neigh_seq_state *state = seq->private;
2133         struct neigh_table *tbl = state->tbl;
2134
2135         pn = pn->next;
2136         while (!pn) {
2137                 if (++state->bucket > PNEIGH_HASHMASK)
2138                         break;
2139                 pn = tbl->phash_buckets[state->bucket];
2140                 if (pn)
2141                         break;
2142         }
2143
2144         if (pn && pos)
2145                 --(*pos);
2146
2147         return pn;
2148 }
2149
2150 static struct pneigh_entry *pneigh_get_idx(struct seq_file *seq, loff_t *pos)
2151 {
2152         struct pneigh_entry *pn = pneigh_get_first(seq);
2153
2154         if (pn) {
2155                 while (*pos) {
2156                         pn = pneigh_get_next(seq, pn, pos);
2157                         if (!pn)
2158                                 break;
2159                 }
2160         }
2161         return *pos ? NULL : pn;
2162 }
2163
2164 static void *neigh_get_idx_any(struct seq_file *seq, loff_t *pos)
2165 {
2166         struct neigh_seq_state *state = seq->private;
2167         void *rc;
2168
2169         rc = neigh_get_idx(seq, pos);
2170         if (!rc && !(state->flags & NEIGH_SEQ_NEIGH_ONLY))
2171                 rc = pneigh_get_idx(seq, pos);
2172
2173         return rc;
2174 }
2175
2176 void *neigh_seq_start(struct seq_file *seq, loff_t *pos, struct neigh_table *tbl, unsigned int neigh_seq_flags)
2177 {
2178         struct neigh_seq_state *state = seq->private;
2179         loff_t pos_minus_one;
2180
2181         state->tbl = tbl;
2182         state->bucket = 0;
2183         state->flags = (neigh_seq_flags & ~NEIGH_SEQ_IS_PNEIGH);
2184
2185         read_lock_bh(&tbl->lock);
2186
2187         pos_minus_one = *pos - 1;
2188         return *pos ? neigh_get_idx_any(seq, &pos_minus_one) : SEQ_START_TOKEN;
2189 }
2190 EXPORT_SYMBOL(neigh_seq_start);
2191
2192 void *neigh_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2193 {
2194         struct neigh_seq_state *state;
2195         void *rc;
2196
2197         if (v == SEQ_START_TOKEN) {
2198                 rc = neigh_get_idx(seq, pos);
2199                 goto out;
2200         }
2201
2202         state = seq->private;
2203         if (!(state->flags & NEIGH_SEQ_IS_PNEIGH)) {
2204                 rc = neigh_get_next(seq, v, NULL);
2205                 if (rc)
2206                         goto out;
2207                 if (!(state->flags & NEIGH_SEQ_NEIGH_ONLY))
2208                         rc = pneigh_get_first(seq);
2209         } else {
2210                 BUG_ON(state->flags & NEIGH_SEQ_NEIGH_ONLY);
2211                 rc = pneigh_get_next(seq, v, NULL);
2212         }
2213 out:
2214         ++(*pos);
2215         return rc;
2216 }
2217 EXPORT_SYMBOL(neigh_seq_next);
2218
2219 void neigh_seq_stop(struct seq_file *seq, void *v)
2220 {
2221         struct neigh_seq_state *state = seq->private;
2222         struct neigh_table *tbl = state->tbl;
2223
2224         read_unlock_bh(&tbl->lock);
2225 }
2226 EXPORT_SYMBOL(neigh_seq_stop);
2227
2228 /* statistics via seq_file */
2229
2230 static void *neigh_stat_seq_start(struct seq_file *seq, loff_t *pos)
2231 {
2232         struct proc_dir_entry *pde = seq->private;
2233         struct neigh_table *tbl = pde->data;
2234         int cpu;
2235
2236         if (*pos == 0)
2237                 return SEQ_START_TOKEN;
2238
2239         for (cpu = *pos-1; cpu < NR_CPUS; ++cpu) {
2240                 if (!cpu_possible(cpu))
2241                         continue;
2242                 *pos = cpu+1;
2243                 return per_cpu_ptr(tbl->stats, cpu);
2244         }
2245         return NULL;
2246 }
2247
2248 static void *neigh_stat_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2249 {
2250         struct proc_dir_entry *pde = seq->private;
2251         struct neigh_table *tbl = pde->data;
2252         int cpu;
2253
2254         for (cpu = *pos; cpu < NR_CPUS; ++cpu) {
2255                 if (!cpu_possible(cpu))
2256                         continue;
2257                 *pos = cpu+1;
2258                 return per_cpu_ptr(tbl->stats, cpu);
2259         }
2260         return NULL;
2261 }
2262
2263 static void neigh_stat_seq_stop(struct seq_file *seq, void *v)
2264 {
2265
2266 }
2267
2268 static int neigh_stat_seq_show(struct seq_file *seq, void *v)
2269 {
2270         struct proc_dir_entry *pde = seq->private;
2271         struct neigh_table *tbl = pde->data;
2272         struct neigh_statistics *st = v;
2273
2274         if (v == SEQ_START_TOKEN) {
2275                 seq_printf(seq, "entries  allocs destroys hash_grows  lookups hits  res_failed  rcv_probes_mcast rcv_probes_ucast  periodic_gc_runs forced_gc_runs\n");
2276                 return 0;
2277         }
2278
2279         seq_printf(seq, "%08x  %08lx %08lx %08lx  %08lx %08lx  %08lx  "
2280                         "%08lx %08lx  %08lx %08lx\n",
2281                    atomic_read(&tbl->entries),
2282
2283                    st->allocs,
2284                    st->destroys,
2285                    st->hash_grows,
2286
2287                    st->lookups,
2288                    st->hits,
2289
2290                    st->res_failed,
2291
2292                    st->rcv_probes_mcast,
2293                    st->rcv_probes_ucast,
2294
2295                    st->periodic_gc_runs,
2296                    st->forced_gc_runs
2297                    );
2298
2299         return 0;
2300 }
2301
2302 static struct seq_operations neigh_stat_seq_ops = {
2303         .start  = neigh_stat_seq_start,
2304         .next   = neigh_stat_seq_next,
2305         .stop   = neigh_stat_seq_stop,
2306         .show   = neigh_stat_seq_show,
2307 };
2308
2309 static int neigh_stat_seq_open(struct inode *inode, struct file *file)
2310 {
2311         int ret = seq_open(file, &neigh_stat_seq_ops);
2312
2313         if (!ret) {
2314                 struct seq_file *sf = file->private_data;
2315                 sf->private = PDE(inode);
2316         }
2317         return ret;
2318 };
2319
2320 static struct file_operations neigh_stat_seq_fops = {
2321         .owner   = THIS_MODULE,
2322         .open    = neigh_stat_seq_open,
2323         .read    = seq_read,
2324         .llseek  = seq_lseek,
2325         .release = seq_release,
2326 };
2327
2328 #endif /* CONFIG_PROC_FS */
2329
2330 #ifdef CONFIG_ARPD
2331 void neigh_app_ns(struct neighbour *n)
2332 {
2333         struct nlmsghdr  *nlh;
2334         int size = NLMSG_SPACE(sizeof(struct ndmsg) + 256);
2335         struct sk_buff *skb = alloc_skb(size, GFP_ATOMIC);
2336
2337         if (!skb)
2338                 return;
2339
2340         if (neigh_fill_info(skb, n, 0, 0, RTM_GETNEIGH, 0) < 0) {
2341                 kfree_skb(skb);
2342                 return;
2343         }
2344         nlh                        = (struct nlmsghdr *)skb->data;
2345         nlh->nlmsg_flags           = NLM_F_REQUEST;
2346         NETLINK_CB(skb).dst_group  = RTNLGRP_NEIGH;
2347         netlink_broadcast(rtnl, skb, 0, RTNLGRP_NEIGH, GFP_ATOMIC);
2348 }
2349
2350 static void neigh_app_notify(struct neighbour *n)
2351 {
2352         struct nlmsghdr *nlh;
2353         int size = NLMSG_SPACE(sizeof(struct ndmsg) + 256);
2354         struct sk_buff *skb = alloc_skb(size, GFP_ATOMIC);
2355
2356         if (!skb)
2357                 return;
2358
2359         if (neigh_fill_info(skb, n, 0, 0, RTM_NEWNEIGH, 0) < 0) {
2360                 kfree_skb(skb);
2361                 return;
2362         }
2363         nlh                        = (struct nlmsghdr *)skb->data;
2364         NETLINK_CB(skb).dst_group  = RTNLGRP_NEIGH;
2365         netlink_broadcast(rtnl, skb, 0, RTNLGRP_NEIGH, GFP_ATOMIC);
2366 }
2367
2368 #endif /* CONFIG_ARPD */
2369
2370 #ifdef CONFIG_SYSCTL
2371
2372 static struct neigh_sysctl_table {
2373         struct ctl_table_header *sysctl_header;
2374         ctl_table               neigh_vars[__NET_NEIGH_MAX];
2375         ctl_table               neigh_dev[2];
2376         ctl_table               neigh_neigh_dir[2];
2377         ctl_table               neigh_proto_dir[2];
2378         ctl_table               neigh_root_dir[2];
2379 } neigh_sysctl_template = {
2380         .neigh_vars = {
2381                 {
2382                         .ctl_name       = NET_NEIGH_MCAST_SOLICIT,
2383                         .procname       = "mcast_solicit",
2384                         .maxlen         = sizeof(int),
2385                         .mode           = 0644,
2386                         .proc_handler   = &proc_dointvec,
2387                 },
2388                 {
2389                         .ctl_name       = NET_NEIGH_UCAST_SOLICIT,
2390                         .procname       = "ucast_solicit",
2391                         .maxlen         = sizeof(int),
2392                         .mode           = 0644,
2393                         .proc_handler   = &proc_dointvec,
2394                 },
2395                 {
2396                         .ctl_name       = NET_NEIGH_APP_SOLICIT,
2397                         .procname       = "app_solicit",
2398                         .maxlen         = sizeof(int),
2399                         .mode           = 0644,
2400                         .proc_handler   = &proc_dointvec,
2401                 },
2402                 {
2403                         .ctl_name       = NET_NEIGH_RETRANS_TIME,
2404                         .procname       = "retrans_time",
2405                         .maxlen         = sizeof(int),
2406                         .mode           = 0644,
2407                         .proc_handler   = &proc_dointvec_userhz_jiffies,
2408                 },
2409                 {
2410                         .ctl_name       = NET_NEIGH_REACHABLE_TIME,
2411                         .procname       = "base_reachable_time",
2412                         .maxlen         = sizeof(int),
2413                         .mode           = 0644,
2414                         .proc_handler   = &proc_dointvec_jiffies,
2415                         .strategy       = &sysctl_jiffies,
2416                 },
2417                 {
2418                         .ctl_name       = NET_NEIGH_DELAY_PROBE_TIME,
2419                         .procname       = "delay_first_probe_time",
2420                         .maxlen         = sizeof(int),
2421                         .mode           = 0644,
2422                         .proc_handler   = &proc_dointvec_jiffies,
2423                         .strategy       = &sysctl_jiffies,
2424                 },
2425                 {
2426                         .ctl_name       = NET_NEIGH_GC_STALE_TIME,
2427                         .procname       = "gc_stale_time",
2428                         .maxlen         = sizeof(int),
2429                         .mode           = 0644,
2430                         .proc_handler   = &proc_dointvec_jiffies,
2431                         .strategy       = &sysctl_jiffies,
2432                 },
2433                 {
2434                         .ctl_name       = NET_NEIGH_UNRES_QLEN,
2435                         .procname       = "unres_qlen",
2436                         .maxlen         = sizeof(int),
2437                         .mode           = 0644,
2438                         .proc_handler   = &proc_dointvec,
2439                 },
2440                 {
2441                         .ctl_name       = NET_NEIGH_PROXY_QLEN,
2442                         .procname       = "proxy_qlen",
2443                         .maxlen         = sizeof(int),
2444                         .mode           = 0644,
2445                         .proc_handler   = &proc_dointvec,
2446                 },
2447                 {
2448                         .ctl_name       = NET_NEIGH_ANYCAST_DELAY,
2449                         .procname       = "anycast_delay",
2450                         .maxlen         = sizeof(int),
2451                         .mode           = 0644,
2452                         .proc_handler   = &proc_dointvec_userhz_jiffies,
2453                 },
2454                 {
2455                         .ctl_name       = NET_NEIGH_PROXY_DELAY,
2456                         .procname       = "proxy_delay",
2457                         .maxlen         = sizeof(int),
2458                         .mode           = 0644,
2459                         .proc_handler   = &proc_dointvec_userhz_jiffies,
2460                 },
2461                 {
2462                         .ctl_name       = NET_NEIGH_LOCKTIME,
2463                         .procname       = "locktime",
2464                         .maxlen         = sizeof(int),
2465                         .mode           = 0644,
2466                         .proc_handler   = &proc_dointvec_userhz_jiffies,
2467                 },
2468                 {
2469                         .ctl_name       = NET_NEIGH_GC_INTERVAL,
2470                         .procname       = "gc_interval",
2471                         .maxlen         = sizeof(int),
2472                         .mode           = 0644,
2473                         .proc_handler   = &proc_dointvec_jiffies,
2474                         .strategy       = &sysctl_jiffies,
2475                 },
2476                 {
2477                         .ctl_name       = NET_NEIGH_GC_THRESH1,
2478                         .procname       = "gc_thresh1",
2479                         .maxlen         = sizeof(int),
2480                         .mode           = 0644,
2481                         .proc_handler   = &proc_dointvec,
2482                 },
2483                 {
2484                         .ctl_name       = NET_NEIGH_GC_THRESH2,
2485                         .procname       = "gc_thresh2",
2486                         .maxlen         = sizeof(int),
2487                         .mode           = 0644,
2488                         .proc_handler   = &proc_dointvec,
2489                 },
2490                 {
2491                         .ctl_name       = NET_NEIGH_GC_THRESH3,
2492                         .procname       = "gc_thresh3",
2493                         .maxlen         = sizeof(int),
2494                         .mode           = 0644,
2495                         .proc_handler   = &proc_dointvec,
2496                 },
2497                 {
2498                         .ctl_name       = NET_NEIGH_RETRANS_TIME_MS,
2499                         .procname       = "retrans_time_ms",
2500                         .maxlen         = sizeof(int),
2501                         .mode           = 0644,
2502                         .proc_handler   = &proc_dointvec_ms_jiffies,
2503                         .strategy       = &sysctl_ms_jiffies,
2504                 },
2505                 {
2506                         .ctl_name       = NET_NEIGH_REACHABLE_TIME_MS,
2507                         .procname       = "base_reachable_time_ms",
2508                         .maxlen         = sizeof(int),
2509                         .mode           = 0644,
2510                         .proc_handler   = &proc_dointvec_ms_jiffies,
2511                         .strategy       = &sysctl_ms_jiffies,
2512                 },
2513         },
2514         .neigh_dev = {
2515                 {
2516                         .ctl_name       = NET_PROTO_CONF_DEFAULT,
2517                         .procname       = "default",
2518                         .mode           = 0555,
2519                 },
2520         },
2521         .neigh_neigh_dir = {
2522                 {
2523                         .procname       = "neigh",
2524                         .mode           = 0555,
2525                 },
2526         },
2527         .neigh_proto_dir = {
2528                 {
2529                         .mode           = 0555,
2530                 },
2531         },
2532         .neigh_root_dir = {
2533                 {
2534                         .ctl_name       = CTL_NET,
2535                         .procname       = "net",
2536                         .mode           = 0555,
2537                 },
2538         },
2539 };
2540
2541 int neigh_sysctl_register(struct net_device *dev, struct neigh_parms *p,
2542                           int p_id, int pdev_id, char *p_name,
2543                           proc_handler *handler, ctl_handler *strategy)
2544 {
2545         struct neigh_sysctl_table *t = kmalloc(sizeof(*t), GFP_KERNEL);
2546         const char *dev_name_source = NULL;
2547         char *dev_name = NULL;
2548         int err = 0;
2549
2550         if (!t)
2551                 return -ENOBUFS;
2552         memcpy(t, &neigh_sysctl_template, sizeof(*t));
2553         t->neigh_vars[0].data  = &p->mcast_probes;
2554         t->neigh_vars[1].data  = &p->ucast_probes;
2555         t->neigh_vars[2].data  = &p->app_probes;
2556         t->neigh_vars[3].data  = &p->retrans_time;
2557         t->neigh_vars[4].data  = &p->base_reachable_time;
2558         t->neigh_vars[5].data  = &p->delay_probe_time;
2559         t->neigh_vars[6].data  = &p->gc_staletime;
2560         t->neigh_vars[7].data  = &p->queue_len;
2561         t->neigh_vars[8].data  = &p->proxy_qlen;
2562         t->neigh_vars[9].data  = &p->anycast_delay;
2563         t->neigh_vars[10].data = &p->proxy_delay;
2564         t->neigh_vars[11].data = &p->locktime;
2565
2566         if (dev) {
2567                 dev_name_source = dev->name;
2568                 t->neigh_dev[0].ctl_name = dev->ifindex;
2569                 t->neigh_vars[12].procname = NULL;
2570                 t->neigh_vars[13].procname = NULL;
2571                 t->neigh_vars[14].procname = NULL;
2572                 t->neigh_vars[15].procname = NULL;
2573         } else {
2574                 dev_name_source = t->neigh_dev[0].procname;
2575                 t->neigh_vars[12].data = (int *)(p + 1);
2576                 t->neigh_vars[13].data = (int *)(p + 1) + 1;
2577                 t->neigh_vars[14].data = (int *)(p + 1) + 2;
2578                 t->neigh_vars[15].data = (int *)(p + 1) + 3;
2579         }
2580
2581         t->neigh_vars[16].data  = &p->retrans_time;
2582         t->neigh_vars[17].data  = &p->base_reachable_time;
2583
2584         if (handler || strategy) {
2585                 /* RetransTime */
2586                 t->neigh_vars[3].proc_handler = handler;
2587                 t->neigh_vars[3].strategy = strategy;
2588                 t->neigh_vars[3].extra1 = dev;
2589                 /* ReachableTime */
2590                 t->neigh_vars[4].proc_handler = handler;
2591                 t->neigh_vars[4].strategy = strategy;
2592                 t->neigh_vars[4].extra1 = dev;
2593                 /* RetransTime (in milliseconds)*/
2594                 t->neigh_vars[16].proc_handler = handler;
2595                 t->neigh_vars[16].strategy = strategy;
2596                 t->neigh_vars[16].extra1 = dev;
2597                 /* ReachableTime (in milliseconds) */
2598                 t->neigh_vars[17].proc_handler = handler;
2599                 t->neigh_vars[17].strategy = strategy;
2600                 t->neigh_vars[17].extra1 = dev;
2601         }
2602
2603         dev_name = kstrdup(dev_name_source, GFP_KERNEL);
2604         if (!dev_name) {
2605                 err = -ENOBUFS;
2606                 goto free;
2607         }
2608
2609         t->neigh_dev[0].procname = dev_name;
2610
2611         t->neigh_neigh_dir[0].ctl_name = pdev_id;
2612
2613         t->neigh_proto_dir[0].procname = p_name;
2614         t->neigh_proto_dir[0].ctl_name = p_id;
2615
2616         t->neigh_dev[0].child          = t->neigh_vars;
2617         t->neigh_neigh_dir[0].child    = t->neigh_dev;
2618         t->neigh_proto_dir[0].child    = t->neigh_neigh_dir;
2619         t->neigh_root_dir[0].child     = t->neigh_proto_dir;
2620
2621         t->sysctl_header = register_sysctl_table(t->neigh_root_dir, 0);
2622         if (!t->sysctl_header) {
2623                 err = -ENOBUFS;
2624                 goto free_procname;
2625         }
2626         p->sysctl_table = t;
2627         return 0;
2628
2629         /* error path */
2630  free_procname:
2631         kfree(dev_name);
2632  free:
2633         kfree(t);
2634
2635         return err;
2636 }
2637
2638 void neigh_sysctl_unregister(struct neigh_parms *p)
2639 {
2640         if (p->sysctl_table) {
2641                 struct neigh_sysctl_table *t = p->sysctl_table;
2642                 p->sysctl_table = NULL;
2643                 unregister_sysctl_table(t->sysctl_header);
2644                 kfree(t->neigh_dev[0].procname);
2645                 kfree(t);
2646         }
2647 }
2648
2649 #endif  /* CONFIG_SYSCTL */
2650
2651 EXPORT_SYMBOL(__neigh_event_send);
2652 EXPORT_SYMBOL(neigh_add);
2653 EXPORT_SYMBOL(neigh_changeaddr);
2654 EXPORT_SYMBOL(neigh_compat_output);
2655 EXPORT_SYMBOL(neigh_connected_output);
2656 EXPORT_SYMBOL(neigh_create);
2657 EXPORT_SYMBOL(neigh_delete);
2658 EXPORT_SYMBOL(neigh_destroy);
2659 EXPORT_SYMBOL(neigh_dump_info);
2660 EXPORT_SYMBOL(neigh_event_ns);
2661 EXPORT_SYMBOL(neigh_ifdown);
2662 EXPORT_SYMBOL(neigh_lookup);
2663 EXPORT_SYMBOL(neigh_lookup_nodev);
2664 EXPORT_SYMBOL(neigh_parms_alloc);
2665 EXPORT_SYMBOL(neigh_parms_release);
2666 EXPORT_SYMBOL(neigh_rand_reach_time);
2667 EXPORT_SYMBOL(neigh_resolve_output);
2668 EXPORT_SYMBOL(neigh_table_clear);
2669 EXPORT_SYMBOL(neigh_table_init);
2670 EXPORT_SYMBOL(neigh_update);
2671 EXPORT_SYMBOL(neigh_update_hhs);
2672 EXPORT_SYMBOL(pneigh_enqueue);
2673 EXPORT_SYMBOL(pneigh_lookup);
2674 EXPORT_SYMBOL(neightbl_dump_info);
2675 EXPORT_SYMBOL(neightbl_set);
2676
2677 #ifdef CONFIG_ARPD
2678 EXPORT_SYMBOL(neigh_app_ns);
2679 #endif
2680 #ifdef CONFIG_SYSCTL
2681 EXPORT_SYMBOL(neigh_sysctl_register);
2682 EXPORT_SYMBOL(neigh_sysctl_unregister);
2683 #endif