err.no Git - linux-2.6/blob - 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/types.h>
  19 #include <linux/kernel.h>
  20 #include <linux/module.h>
  21 #include <linux/socket.h>
  22 #include <linux/netdevice.h>
  23 #include <linux/proc_fs.h>
  24 #ifdef CONFIG_SYSCTL
  25 #include <linux/sysctl.h>
  26 #endif
  27 #include <linux/times.h>
  28 #include <net/net_namespace.h>
  29 #include <net/neighbour.h>
  30 #include <net/dst.h>
  31 #include <net/sock.h>
  32 #include <net/netevent.h>
  33 #include <net/netlink.h>
  34 #include <linux/rtnetlink.h>
  35 #include <linux/random.h>
  36 #include <linux/string.h>
  37 #include <linux/log2.h>
  38
  39 #define NEIGH_DEBUG 1
  40
  41 #define NEIGH_PRINTK(x...) printk(x)
  42 #define NEIGH_NOPRINTK(x...) do { ; } while(0)
  43 #define NEIGH_PRINTK0 NEIGH_PRINTK
  44 #define NEIGH_PRINTK1 NEIGH_NOPRINTK
  45 #define NEIGH_PRINTK2 NEIGH_NOPRINTK
  46
  47 #if NEIGH_DEBUG >= 1
  48 #undef NEIGH_PRINTK1
  49 #define NEIGH_PRINTK1 NEIGH_PRINTK
  50 #endif
  51 #if NEIGH_DEBUG >= 2
  52 #undef NEIGH_PRINTK2
  53 #define NEIGH_PRINTK2 NEIGH_PRINTK
  54 #endif
  55
  56 #define PNEIGH_HASHMASK         0xF
  57
  58 static void neigh_timer_handler(unsigned long arg);
  59 static void __neigh_notify(struct neighbour *n, int type, int flags);
  60 static void neigh_update_notify(struct neighbour *neigh);
  61 static int pneigh_ifdown(struct neigh_table *tbl, struct net_device *dev);
  62
  63 static struct neigh_table *neigh_tables;
  64 #ifdef CONFIG_PROC_FS
  65 static const struct file_operations neigh_stat_seq_fops;
  66 #endif
  67
  68 /*
  69    Neighbour hash table buckets are protected with rwlock tbl->lock.
  70
  71    - All the scans/updates to hash buckets MUST be made under this lock.
  72    - NOTHING clever should be made under this lock: no callbacks
  73      to protocol backends, no attempts to send something to network.
  74      It will result in deadlocks, if backend/driver wants to use neighbour
  75      cache.
  76    - If the entry requires some non-trivial actions, increase
  77      its reference count and release table lock.
  78
  79    Neighbour entries are protected:
  80    - with reference count.
  81    - with rwlock neigh->lock
  82
  83    Reference count prevents destruction.
  84
  85    neigh->lock mainly serializes ll address data and its validity state.
  86    However, the same lock is used to protect another entry fields:
  87     - timer
  88     - resolution queue
  89
  90    Again, nothing clever shall be made under neigh->lock,
  91    the most complicated procedure, which we allow is dev->hard_header.
  92    It is supposed, that dev->hard_header is simplistic and does
  93    not make callbacks to neighbour tables.
  94
  95    The last lock is neigh_tbl_lock. It is pure SMP lock, protecting
  96    list of neighbour tables. This list is used only in process context,
  97  */
  98
  99 static DEFINE_RWLOCK(neigh_tbl_lock);
 100
 101 static int neigh_blackhole(struct sk_buff *skb)
 102 {
 103         kfree_skb(skb);
 104         return -ENETDOWN;
 105 }
 106
 107 static void neigh_cleanup_and_release(struct neighbour *neigh)
 108 {
 109         if (neigh->parms->neigh_cleanup)
 110                 neigh->parms->neigh_cleanup(neigh);
 111
 112         __neigh_notify(neigh, RTM_DELNEIGH, 0);
 113         neigh_release(neigh);
 114 }
 115
 116 /*
 117  * It is random distribution in the interval (1/2)*base...(3/2)*base.
 118  * It corresponds to default IPv6 settings and is not overridable,
 119  * because it is really reasonable choice.
 120  */
 121
 122 unsigned long neigh_rand_reach_time(unsigned long base)
 123 {
 124         return (base ? (net_random() % base) + (base >> 1) : 0);
 125 }
 126 EXPORT_SYMBOL(neigh_rand_reach_time);
 127
 128
 129 static int neigh_forced_gc(struct neigh_table *tbl)
 130 {
 131         int shrunk = 0;
 132         int i;
 133
 134         NEIGH_CACHE_STAT_INC(tbl, forced_gc_runs);
 135
 136         write_lock_bh(&tbl->lock);
 137         for (i = 0; i <= tbl->hash_mask; i++) {
 138                 struct neighbour *n, **np;
 139
 140                 np = &tbl->hash_buckets[i];
 141                 while ((n = *np) != NULL) {
 142                         /* Neighbour record may be discarded if:
 143                          * - nobody refers to it.
 144                          * - it is not permanent
 145                          */
 146                         write_lock(&n->lock);
 147                         if (atomic_read(&n->refcnt) == 1 &&
 148                             !(n->nud_state & NUD_PERMANENT)) {
 149                                 *np     = n->next;
 150                                 n->dead = 1;
 151                                 shrunk  = 1;
 152                                 write_unlock(&n->lock);
 153                                 neigh_cleanup_and_release(n);
 154                                 continue;
 155                         }
 156                         write_unlock(&n->lock);
 157                         np = &n->next;
 158                 }
 159         }
 160
 161         tbl->last_flush = jiffies;
 162
 163         write_unlock_bh(&tbl->lock);
 164
 165         return shrunk;
 166 }
 167
 168 static void neigh_add_timer(struct neighbour *n, unsigned long when)
 169 {
 170         neigh_hold(n);
 171         if (unlikely(mod_timer(&n->timer, when))) {
 172                 printk("NEIGH: BUG, double timer add, state is %x\n",
 173                        n->nud_state);
 174                 dump_stack();
 175         }
 176 }
 177
 178 static int neigh_del_timer(struct neighbour *n)
 179 {
 180         if ((n->nud_state & NUD_IN_TIMER) &&
 181             del_timer(&n->timer)) {
 182                 neigh_release(n);
 183                 return 1;
 184         }
 185         return 0;
 186 }
 187
 188 static void pneigh_queue_purge(struct sk_buff_head *list)
 189 {
 190         struct sk_buff *skb;
 191
 192         while ((skb = skb_dequeue(list)) != NULL) {
 193                 dev_put(skb->dev);
 194                 kfree_skb(skb);
 195         }
 196 }
 197
 198 static void neigh_flush_dev(struct neigh_table *tbl, struct net_device *dev)
 199 {
 200         int i;
 201
 202         for (i = 0; i <= tbl->hash_mask; i++) {
 203                 struct neighbour *n, **np = &tbl->hash_buckets[i];
 204
 205                 while ((n = *np) != NULL) {
 206                         if (dev && n->dev != dev) {
 207                                 np = &n->next;
 208                                 continue;
 209                         }
 210                         *np = n->next;
 211                         write_lock(&n->lock);
 212                         neigh_del_timer(n);
 213                         n->dead = 1;
 214
 215                         if (atomic_read(&n->refcnt) != 1) {
 216                                 /* The most unpleasant situation.
 217                                    We must destroy neighbour entry,
 218                                    but someone still uses it.
 219
 220                                    The destroy will be delayed until
 221                                    the last user releases us, but
 222                                    we must kill timers etc. and move
 223                                    it to safe state.
 224                                  */
 225                                 skb_queue_purge(&n->arp_queue);
 226                                 n->output = neigh_blackhole;
 227                                 if (n->nud_state & NUD_VALID)
 228                                         n->nud_state = NUD_NOARP;
 229                                 else
 230                                         n->nud_state = NUD_NONE;
 231                                 NEIGH_PRINTK2("neigh %p is stray.\n", n);
 232                         }
 233                         write_unlock(&n->lock);
 234                         neigh_cleanup_and_release(n);
 235                 }
 236         }
 237 }
 238
 239 void neigh_changeaddr(struct neigh_table *tbl, struct net_device *dev)
 240 {
 241         write_lock_bh(&tbl->lock);
 242         neigh_flush_dev(tbl, dev);
 243         write_unlock_bh(&tbl->lock);
 244 }
 245 EXPORT_SYMBOL(neigh_changeaddr);
 246
 247 int neigh_ifdown(struct neigh_table *tbl, struct net_device *dev)
 248 {
 249         write_lock_bh(&tbl->lock);
 250         neigh_flush_dev(tbl, dev);
 251         pneigh_ifdown(tbl, dev);
 252         write_unlock_bh(&tbl->lock);
 253
 254         del_timer_sync(&tbl->proxy_timer);
 255         pneigh_queue_purge(&tbl->proxy_queue);
 256         return 0;
 257 }
 258 EXPORT_SYMBOL(neigh_ifdown);
 259
 260 static struct neighbour *neigh_alloc(struct neigh_table *tbl)
 261 {
 262         struct neighbour *n = NULL;
 263         unsigned long now = jiffies;
 264         int entries;
 265
 266         entries = atomic_inc_return(&tbl->entries) - 1;
 267         if (entries >= tbl->gc_thresh3 ||
 268             (entries >= tbl->gc_thresh2 &&
 269              time_after(now, tbl->last_flush + 5 * HZ))) {
 270                 if (!neigh_forced_gc(tbl) &&
 271                     entries >= tbl->gc_thresh3)
 272                         goto out_entries;
 273         }
 274
 275         n = kmem_cache_zalloc(tbl->kmem_cachep, GFP_ATOMIC);
 276         if (!n)
 277                 goto out_entries;
 278
 279         skb_queue_head_init(&n->arp_queue);
 280         rwlock_init(&n->lock);
 281         n->updated        = n->used = now;
 282         n->nud_state      = NUD_NONE;
 283         n->output         = neigh_blackhole;
 284         n->parms          = neigh_parms_clone(&tbl->parms);
 285         setup_timer(&n->timer, neigh_timer_handler, (unsigned long)n);
 286
 287         NEIGH_CACHE_STAT_INC(tbl, allocs);
 288         n->tbl            = tbl;
 289         atomic_set(&n->refcnt, 1);
 290         n->dead           = 1;
 291 out:
 292         return n;
 293
 294 out_entries:
 295         atomic_dec(&tbl->entries);
 296         goto out;
 297 }
 298
 299 static struct neighbour **neigh_hash_alloc(unsigned int entries)
 300 {
 301         unsigned long size = entries * sizeof(struct neighbour *);
 302         struct neighbour **ret;
 303
 304         if (size <= PAGE_SIZE) {
 305                 ret = kzalloc(size, GFP_ATOMIC);
 306         } else {
 307                 ret = (struct neighbour **)
 308                       __get_free_pages(GFP_ATOMIC|__GFP_ZERO, get_order(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(!is_power_of_2(new_entries));
 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;
 365
 366         NEIGH_CACHE_STAT_INC(tbl, lookups);
 367
 368         read_lock_bh(&tbl->lock);
 369         hash_val = tbl->hash(pkey, dev);
 370         for (n = tbl->hash_buckets[hash_val & tbl->hash_mask]; n; n = n->next) {
 371                 if (dev == n->dev && !memcmp(n->primary_key, pkey, key_len)) {
 372                         neigh_hold(n);
 373                         NEIGH_CACHE_STAT_INC(tbl, hits);
 374                         break;
 375                 }
 376         }
 377         read_unlock_bh(&tbl->lock);
 378         return n;
 379 }
 380 EXPORT_SYMBOL(neigh_lookup);
 381
 382 struct neighbour *neigh_lookup_nodev(struct neigh_table *tbl, struct net *net,
 383                                      const void *pkey)
 384 {
 385         struct neighbour *n;
 386         int key_len = tbl->key_len;
 387         u32 hash_val;
 388
 389         NEIGH_CACHE_STAT_INC(tbl, lookups);
 390
 391         read_lock_bh(&tbl->lock);
 392         hash_val = tbl->hash(pkey, NULL);
 393         for (n = tbl->hash_buckets[hash_val & tbl->hash_mask]; n; n = n->next) {
 394                 if (!memcmp(n->primary_key, pkey, key_len) &&
 395                     net_eq(dev_net(n->dev), net)) {
 396                         neigh_hold(n);
 397                         NEIGH_CACHE_STAT_INC(tbl, hits);
 398                         break;
 399                 }
 400         }
 401         read_unlock_bh(&tbl->lock);
 402         return n;
 403 }
 404 EXPORT_SYMBOL(neigh_lookup_nodev);
 405
 406 struct neighbour *neigh_create(struct neigh_table *tbl, const void *pkey,
 407                                struct net_device *dev)
 408 {
 409         u32 hash_val;
 410         int key_len = tbl->key_len;
 411         int error;
 412         struct neighbour *n1, *rc, *n = neigh_alloc(tbl);
 413
 414         if (!n) {
 415                 rc = ERR_PTR(-ENOBUFS);
 416                 goto out;
 417         }
 418
 419         memcpy(n->primary_key, pkey, key_len);
 420         n->dev = dev;
 421         dev_hold(dev);
 422
 423         /* Protocol specific setup. */
 424         if (tbl->constructor && (error = tbl->constructor(n)) < 0) {
 425                 rc = ERR_PTR(error);
 426                 goto out_neigh_release;
 427         }
 428
 429         /* Device specific setup. */
 430         if (n->parms->neigh_setup &&
 431             (error = n->parms->neigh_setup(n)) < 0) {
 432                 rc = ERR_PTR(error);
 433                 goto out_neigh_release;
 434         }
 435
 436         n->confirmed = jiffies - (n->parms->base_reachable_time << 1);
 437
 438         write_lock_bh(&tbl->lock);
 439
 440         if (atomic_read(&tbl->entries) > (tbl->hash_mask + 1))
 441                 neigh_hash_grow(tbl, (tbl->hash_mask + 1) << 1);
 442
 443         hash_val = tbl->hash(pkey, dev) & tbl->hash_mask;
 444
 445         if (n->parms->dead) {
 446                 rc = ERR_PTR(-EINVAL);
 447                 goto out_tbl_unlock;
 448         }
 449
 450         for (n1 = tbl->hash_buckets[hash_val]; n1; n1 = n1->next) {
 451                 if (dev == n1->dev && !memcmp(n1->primary_key, pkey, key_len)) {
 452                         neigh_hold(n1);
 453                         rc = n1;
 454                         goto out_tbl_unlock;
 455                 }
 456         }
 457
 458         n->next = tbl->hash_buckets[hash_val];
 459         tbl->hash_buckets[hash_val] = n;
 460         n->dead = 0;
 461         neigh_hold(n);
 462         write_unlock_bh(&tbl->lock);
 463         NEIGH_PRINTK2("neigh %p is created.\n", n);
 464         rc = n;
 465 out:
 466         return rc;
 467 out_tbl_unlock:
 468         write_unlock_bh(&tbl->lock);
 469 out_neigh_release:
 470         neigh_release(n);
 471         goto out;
 472 }
 473 EXPORT_SYMBOL(neigh_create);
 474
 475 static u32 pneigh_hash(const void *pkey, int key_len)
 476 {
 477         u32 hash_val = *(u32 *)(pkey + key_len - 4);
 478         hash_val ^= (hash_val >> 16);
 479         hash_val ^= hash_val >> 8;
 480         hash_val ^= hash_val >> 4;
 481         hash_val &= PNEIGH_HASHMASK;
 482         return hash_val;
 483 }
 484
 485 static struct pneigh_entry *__pneigh_lookup_1(struct pneigh_entry *n,
 486                                               struct net *net,
 487                                               const void *pkey,
 488                                               int key_len,
 489                                               struct net_device *dev)
 490 {
 491         while (n) {
 492                 if (!memcmp(n->key, pkey, key_len) &&
 493                     net_eq(pneigh_net(n), net) &&
 494                     (n->dev == dev || !n->dev))
 495                         return n;
 496                 n = n->next;
 497         }
 498         return NULL;
 499 }
 500
 501 struct pneigh_entry *__pneigh_lookup(struct neigh_table *tbl,
 502                 struct net *net, const void *pkey, struct net_device *dev)
 503 {
 504         int key_len = tbl->key_len;
 505         u32 hash_val = pneigh_hash(pkey, key_len);
 506
 507         return __pneigh_lookup_1(tbl->phash_buckets[hash_val],
 508                                  net, pkey, key_len, dev);
 509 }
 510 EXPORT_SYMBOL_GPL(__pneigh_lookup);
 511
 512 struct pneigh_entry * pneigh_lookup(struct neigh_table *tbl,
 513                                     struct net *net, const void *pkey,
 514                                     struct net_device *dev, int creat)
 515 {
 516         struct pneigh_entry *n;
 517         int key_len = tbl->key_len;
 518         u32 hash_val = pneigh_hash(pkey, key_len);
 519
 520         read_lock_bh(&tbl->lock);
 521         n = __pneigh_lookup_1(tbl->phash_buckets[hash_val],
 522                               net, pkey, key_len, dev);
 523         read_unlock_bh(&tbl->lock);
 524
 525         if (n || !creat)
 526                 goto out;
 527
 528         ASSERT_RTNL();
 529
 530         n = kmalloc(sizeof(*n) + key_len, GFP_KERNEL);
 531         if (!n)
 532                 goto out;
 533
 534 #ifdef CONFIG_NET_NS
 535         n->net = hold_net(net);
 536 #endif
 537         memcpy(n->key, pkey, key_len);
 538         n->dev = dev;
 539         if (dev)
 540                 dev_hold(dev);
 541
 542         if (tbl->pconstructor && tbl->pconstructor(n)) {
 543                 if (dev)
 544                         dev_put(dev);
 545                 release_net(net);
 546                 kfree(n);
 547                 n = NULL;
 548                 goto out;
 549         }
 550
 551         write_lock_bh(&tbl->lock);
 552         n->next = tbl->phash_buckets[hash_val];
 553         tbl->phash_buckets[hash_val] = n;
 554         write_unlock_bh(&tbl->lock);
 555 out:
 556         return n;
 557 }
 558 EXPORT_SYMBOL(pneigh_lookup);
 559
 560
 561 int pneigh_delete(struct neigh_table *tbl, struct net *net, const void *pkey,
 562                   struct net_device *dev)
 563 {
 564         struct pneigh_entry *n, **np;
 565         int key_len = tbl->key_len;
 566         u32 hash_val = pneigh_hash(pkey, key_len);
 567
 568         write_lock_bh(&tbl->lock);
 569         for (np = &tbl->phash_buckets[hash_val]; (n = *np) != NULL;
 570              np = &n->next) {
 571                 if (!memcmp(n->key, pkey, key_len) && n->dev == dev &&
 572                     net_eq(pneigh_net(n), net)) {
 573                         *np = n->next;
 574                         write_unlock_bh(&tbl->lock);
 575                         if (tbl->pdestructor)
 576                                 tbl->pdestructor(n);
 577                         if (n->dev)
 578                                 dev_put(n->dev);
 579                         release_net(pneigh_net(n));
 580                         kfree(n);
 581                         return 0;
 582                 }
 583         }
 584         write_unlock_bh(&tbl->lock);
 585         return -ENOENT;
 586 }
 587
 588 static int pneigh_ifdown(struct neigh_table *tbl, struct net_device *dev)
 589 {
 590         struct pneigh_entry *n, **np;
 591         u32 h;
 592
 593         for (h = 0; h <= PNEIGH_HASHMASK; h++) {
 594                 np = &tbl->phash_buckets[h];
 595                 while ((n = *np) != NULL) {
 596                         if (!dev || n->dev == dev) {
 597                                 *np = n->next;
 598                                 if (tbl->pdestructor)
 599                                         tbl->pdestructor(n);
 600                                 if (n->dev)
 601                                         dev_put(n->dev);
 602                                 release_net(pneigh_net(n));
 603                                 kfree(n);
 604                                 continue;
 605                         }
 606                         np = &n->next;
 607                 }
 608         }
 609         return -ENOENT;
 610 }
 611
 612 static void neigh_parms_destroy(struct neigh_parms *parms);
 613
 614 static inline void neigh_parms_put(struct neigh_parms *parms)
 615 {
 616         if (atomic_dec_and_test(&parms->refcnt))
 617                 neigh_parms_destroy(parms);
 618 }
 619
 620 /*
 621  *      neighbour must already be out of the table;
 622  *
 623  */
 624 void neigh_destroy(struct neighbour *neigh)
 625 {
 626         struct hh_cache *hh;
 627
 628         NEIGH_CACHE_STAT_INC(neigh->tbl, destroys);
 629
 630         if (!neigh->dead) {
 631                 printk(KERN_WARNING
 632                        "Destroying alive neighbour %p\n", neigh);
 633                 dump_stack();
 634                 return;
 635         }
 636
 637         if (neigh_del_timer(neigh))
 638                 printk(KERN_WARNING "Impossible event.\n");
 639
 640         while ((hh = neigh->hh) != NULL) {
 641                 neigh->hh = hh->hh_next;
 642                 hh->hh_next = NULL;
 643
 644                 write_seqlock_bh(&hh->hh_lock);
 645                 hh->hh_output = neigh_blackhole;
 646                 write_sequnlock_bh(&hh->hh_lock);
 647                 if (atomic_dec_and_test(&hh->hh_refcnt))
 648                         kfree(hh);
 649         }
 650
 651         skb_queue_purge(&neigh->arp_queue);
 652
 653         dev_put(neigh->dev);
 654         neigh_parms_put(neigh->parms);
 655
 656         NEIGH_PRINTK2("neigh %p is destroyed.\n", neigh);
 657
 658         atomic_dec(&neigh->tbl->entries);
 659         kmem_cache_free(neigh->tbl->kmem_cachep, neigh);
 660 }
 661 EXPORT_SYMBOL(neigh_destroy);
 662
 663 /* Neighbour state is suspicious;
 664    disable fast path.
 665
 666    Called with write_locked neigh.
 667  */
 668 static void neigh_suspect(struct neighbour *neigh)
 669 {
 670         struct hh_cache *hh;
 671
 672         NEIGH_PRINTK2("neigh %p is suspected.\n", neigh);
 673
 674         neigh->output = neigh->ops->output;
 675
 676         for (hh = neigh->hh; hh; hh = hh->hh_next)
 677                 hh->hh_output = neigh->ops->output;
 678 }
 679
 680 /* Neighbour state is OK;
 681    enable fast path.
 682
 683    Called with write_locked neigh.
 684  */
 685 static void neigh_connect(struct neighbour *neigh)
 686 {
 687         struct hh_cache *hh;
 688
 689         NEIGH_PRINTK2("neigh %p is connected.\n", neigh);
 690
 691         neigh->output = neigh->ops->connected_output;
 692
 693         for (hh = neigh->hh; hh; hh = hh->hh_next)
 694                 hh->hh_output = neigh->ops->hh_output;
 695 }
 696
 697 static void neigh_periodic_timer(unsigned long arg)
 698 {
 699         struct neigh_table *tbl = (struct neigh_table *)arg;
 700         struct neighbour *n, **np;
 701         unsigned long expire, now = jiffies;
 702
 703         NEIGH_CACHE_STAT_INC(tbl, periodic_gc_runs);
 704
 705         write_lock(&tbl->lock);
 706
 707         /*
 708          *      periodically recompute ReachableTime from random function
 709          */
 710
 711         if (time_after(now, tbl->last_rand + 300 * HZ)) {
 712                 struct neigh_parms *p;
 713                 tbl->last_rand = now;
 714                 for (p = &tbl->parms; p; p = p->next)
 715                         p->reachable_time =
 716                                 neigh_rand_reach_time(p->base_reachable_time);
 717         }
 718
 719         np = &tbl->hash_buckets[tbl->hash_chain_gc];
 720         tbl->hash_chain_gc = ((tbl->hash_chain_gc + 1) & tbl->hash_mask);
 721
 722         while ((n = *np) != NULL) {
 723                 unsigned int state;
 724
 725                 write_lock(&n->lock);
 726
 727                 state = n->nud_state;
 728                 if (state & (NUD_PERMANENT | NUD_IN_TIMER)) {
 729                         write_unlock(&n->lock);
 730                         goto next_elt;
 731                 }
 732
 733                 if (time_before(n->used, n->confirmed))
 734                         n->used = n->confirmed;
 735
 736                 if (atomic_read(&n->refcnt) == 1 &&
 737                     (state == NUD_FAILED ||
 738                      time_after(now, n->used + n->parms->gc_staletime))) {
 739                         *np = n->next;
 740                         n->dead = 1;
 741                         write_unlock(&n->lock);
 742                         neigh_cleanup_and_release(n);
 743                         continue;
 744                 }
 745                 write_unlock(&n->lock);
 746
 747 next_elt:
 748                 np = &n->next;
 749         }
 750
 751         /* Cycle through all hash buckets every base_reachable_time/2 ticks.
 752          * ARP entry timeouts range from 1/2 base_reachable_time to 3/2
 753          * base_reachable_time.
 754          */
 755         expire = tbl->parms.base_reachable_time >> 1;
 756         expire /= (tbl->hash_mask + 1);
 757         if (!expire)
 758                 expire = 1;
 759
 760         if (expire>HZ)
 761                 mod_timer(&tbl->gc_timer, round_jiffies(now + expire));
 762         else
 763                 mod_timer(&tbl->gc_timer, now + expire);
 764
 765         write_unlock(&tbl->lock);
 766 }
 767
 768 static __inline__ int neigh_max_probes(struct neighbour *n)
 769 {
 770         struct neigh_parms *p = n->parms;
 771         return (n->nud_state & NUD_PROBE ?
 772                 p->ucast_probes :
 773                 p->ucast_probes + p->app_probes + p->mcast_probes);
 774 }
 775
 776 /* Called when a timer expires for a neighbour entry. */
 777
 778 static void neigh_timer_handler(unsigned long arg)
 779 {
 780         unsigned long now, next;
 781         struct neighbour *neigh = (struct neighbour *)arg;
 782         unsigned state;
 783         int notify = 0;
 784
 785         write_lock(&neigh->lock);
 786
 787         state = neigh->nud_state;
 788         now = jiffies;
 789         next = now + HZ;
 790
 791         if (!(state & NUD_IN_TIMER)) {
 792 #ifndef CONFIG_SMP
 793                 printk(KERN_WARNING "neigh: timer & !nud_in_timer\n");
 794 #endif
 795                 goto out;
 796         }
 797
 798         if (state & NUD_REACHABLE) {
 799                 if (time_before_eq(now,
 800                                    neigh->confirmed + neigh->parms->reachable_time)) {
 801                         NEIGH_PRINTK2("neigh %p is still alive.\n", neigh);
 802                         next = neigh->confirmed + neigh->parms->reachable_time;
 803                 } else if (time_before_eq(now,
 804                                           neigh->used + neigh->parms->delay_probe_time)) {
 805                         NEIGH_PRINTK2("neigh %p is delayed.\n", neigh);
 806                         neigh->nud_state = NUD_DELAY;
 807                         neigh->updated = jiffies;
 808                         neigh_suspect(neigh);
 809                         next = now + neigh->parms->delay_probe_time;
 810                 } else {
 811                         NEIGH_PRINTK2("neigh %p is suspected.\n", neigh);
 812                         neigh->nud_state = NUD_STALE;
 813                         neigh->updated = jiffies;
 814                         neigh_suspect(neigh);
 815                         notify = 1;
 816                 }
 817         } else if (state & NUD_DELAY) {
 818                 if (time_before_eq(now,
 819                                    neigh->confirmed + neigh->parms->delay_probe_time)) {
 820                         NEIGH_PRINTK2("neigh %p is now reachable.\n", neigh);
 821                         neigh->nud_state = NUD_REACHABLE;
 822                         neigh->updated = jiffies;
 823                         neigh_connect(neigh);
 824                         notify = 1;
 825                         next = neigh->confirmed + neigh->parms->reachable_time;
 826                 } else {
 827                         NEIGH_PRINTK2("neigh %p is probed.\n", neigh);
 828                         neigh->nud_state = NUD_PROBE;
 829                         neigh->updated = jiffies;
 830                         atomic_set(&neigh->probes, 0);
 831                         next = now + neigh->parms->retrans_time;
 832                 }
 833         } else {
 834                 /* NUD_PROBE|NUD_INCOMPLETE */
 835                 next = now + neigh->parms->retrans_time;
 836         }
 837
 838         if ((neigh->nud_state & (NUD_INCOMPLETE | NUD_PROBE)) &&
 839             atomic_read(&neigh->probes) >= neigh_max_probes(neigh)) {
 840                 struct sk_buff *skb;
 841
 842                 neigh->nud_state = NUD_FAILED;
 843                 neigh->updated = jiffies;
 844                 notify = 1;
 845                 NEIGH_CACHE_STAT_INC(neigh->tbl, res_failed);
 846                 NEIGH_PRINTK2("neigh %p is failed.\n", neigh);
 847
 848                 /* It is very thin place. report_unreachable is very complicated
 849                    routine. Particularly, it can hit the same neighbour entry!
 850
 851                    So that, we try to be accurate and avoid dead loop. --ANK
 852                  */
 853                 while (neigh->nud_state == NUD_FAILED &&
 854                        (skb = __skb_dequeue(&neigh->arp_queue)) != NULL) {
 855                         write_unlock(&neigh->lock);
 856                         neigh->ops->error_report(neigh, skb);
 857                         write_lock(&neigh->lock);
 858                 }
 859                 skb_queue_purge(&neigh->arp_queue);
 860         }
 861
 862         if (neigh->nud_state & NUD_IN_TIMER) {
 863                 if (time_before(next, jiffies + HZ/2))
 864                         next = jiffies + HZ/2;
 865                 if (!mod_timer(&neigh->timer, next))
 866                         neigh_hold(neigh);
 867         }
 868         if (neigh->nud_state & (NUD_INCOMPLETE | NUD_PROBE)) {
 869                 struct sk_buff *skb = skb_peek(&neigh->arp_queue);
 870                 /* keep skb alive even if arp_queue overflows */
 871                 if (skb)
 872                         skb = skb_copy(skb, GFP_ATOMIC);
 873                 write_unlock(&neigh->lock);
 874                 neigh->ops->solicit(neigh, skb);
 875                 atomic_inc(&neigh->probes);
 876                 if (skb)
 877                         kfree_skb(skb);
 878         } else {
 879 out:
 880                 write_unlock(&neigh->lock);
 881         }
 882
 883         if (notify)
 884                 neigh_update_notify(neigh);
 885
 886         neigh_release(neigh);
 887 }
 888
 889 int __neigh_event_send(struct neighbour *neigh, struct sk_buff *skb)
 890 {
 891         int rc;
 892         unsigned long now;
 893
 894         write_lock_bh(&neigh->lock);
 895
 896         rc = 0;
 897         if (neigh->nud_state & (NUD_CONNECTED | NUD_DELAY | NUD_PROBE))
 898                 goto out_unlock_bh;
 899
 900         now = jiffies;
 901
 902         if (!(neigh->nud_state & (NUD_STALE | NUD_INCOMPLETE))) {
 903                 if (neigh->parms->mcast_probes + neigh->parms->app_probes) {
 904                         atomic_set(&neigh->probes, neigh->parms->ucast_probes);
 905                         neigh->nud_state     = NUD_INCOMPLETE;
 906                         neigh->updated = jiffies;
 907                         neigh_add_timer(neigh, now + 1);
 908                 } else {
 909                         neigh->nud_state = NUD_FAILED;
 910                         neigh->updated = jiffies;
 911                         write_unlock_bh(&neigh->lock);
 912
 913                         if (skb)
 914                                 kfree_skb(skb);
 915                         return 1;
 916                 }
 917         } else if (neigh->nud_state & NUD_STALE) {
 918                 NEIGH_PRINTK2("neigh %p is delayed.\n", neigh);
 919                 neigh->nud_state = NUD_DELAY;
 920                 neigh->updated = jiffies;
 921                 neigh_add_timer(neigh,
 922                                 jiffies + neigh->parms->delay_probe_time);
 923         }
 924
 925         if (neigh->nud_state == NUD_INCOMPLETE) {
 926                 if (skb) {
 927                         if (skb_queue_len(&neigh->arp_queue) >=
 928                             neigh->parms->queue_len) {
 929                                 struct sk_buff *buff;
 930                                 buff = neigh->arp_queue.next;
 931                                 __skb_unlink(buff, &neigh->arp_queue);
 932                                 kfree_skb(buff);
 933                         }
 934                         __skb_queue_tail(&neigh->arp_queue, skb);
 935                 }
 936                 rc = 1;
 937         }
 938 out_unlock_bh:
 939         write_unlock_bh(&neigh->lock);
 940         return rc;
 941 }
 942 EXPORT_SYMBOL(__neigh_event_send);
 943
 944 static void neigh_update_hhs(struct neighbour *neigh)
 945 {
 946         struct hh_cache *hh;
 947         void (*update)(struct hh_cache*, const struct net_device*, const unsigned char *)
 948                 = neigh->dev->header_ops->cache_update;
 949
 950         if (update) {
 951                 for (hh = neigh->hh; hh; hh = hh->hh_next) {
 952                         write_seqlock_bh(&hh->hh_lock);
 953                         update(hh, neigh->dev, neigh->ha);
 954                         write_sequnlock_bh(&hh->hh_lock);
 955                 }
 956         }
 957 }
 958
 959
 960
 961 /* Generic update routine.
 962    -- lladdr is new lladdr or NULL, if it is not supplied.
 963    -- new    is new state.
 964    -- flags
 965         NEIGH_UPDATE_F_OVERRIDE allows to override existing lladdr,
 966                                 if it is different.
 967         NEIGH_UPDATE_F_WEAK_OVERRIDE will suspect existing "connected"
 968                                 lladdr instead of overriding it
 969                                 if it is different.
 970                                 It also allows to retain current state
 971                                 if lladdr is unchanged.
 972         NEIGH_UPDATE_F_ADMIN    means that the change is administrative.
 973
 974         NEIGH_UPDATE_F_OVERRIDE_ISROUTER allows to override existing
 975                                 NTF_ROUTER flag.
 976         NEIGH_UPDATE_F_ISROUTER indicates if the neighbour is known as
 977                                 a router.
 978
 979    Caller MUST hold reference count on the entry.
 980  */
 981
 982 int neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new,
 983                  u32 flags)
 984 {
 985         u8 old;
 986         int err;
 987         int notify = 0;
 988         struct net_device *dev;
 989         int update_isrouter = 0;
 990
 991         write_lock_bh(&neigh->lock);
 992
 993         dev    = neigh->dev;
 994         old    = neigh->nud_state;
 995         err    = -EPERM;
 996
 997         if (!(flags & NEIGH_UPDATE_F_ADMIN) &&
 998             (old & (NUD_NOARP | NUD_PERMANENT)))
 999                 goto out;
1000
1001         if (!(new & NUD_VALID)) {
1002                 neigh_del_timer(neigh);
1003                 if (old & NUD_CONNECTED)
1004                         neigh_suspect(neigh);
1005                 neigh->nud_state = new;
1006                 err = 0;
1007                 notify = old & NUD_VALID;
1008                 goto out;
1009         }
1010
1011         /* Compare new lladdr with cached one */
1012         if (!dev->addr_len) {
1013                 /* First case: device needs no address. */
1014                 lladdr = neigh->ha;
1015         } else if (lladdr) {
1016                 /* The second case: if something is already cached
1017                    and a new address is proposed:
1018                    - compare new & old
1019                    - if they are different, check override flag
1020                  */
1021                 if ((old & NUD_VALID) &&
1022                     !memcmp(lladdr, neigh->ha, dev->addr_len))
1023                         lladdr = neigh->ha;
1024         } else {
1025                 /* No address is supplied; if we know something,
1026                    use it, otherwise discard the request.
1027                  */
1028                 err = -EINVAL;
1029                 if (!(old & NUD_VALID))
1030                         goto out;
1031                 lladdr = neigh->ha;
1032         }
1033
1034         if (new & NUD_CONNECTED)
1035                 neigh->confirmed = jiffies;
1036         neigh->updated = jiffies;
1037
1038         /* If entry was valid and address is not changed,
1039            do not change entry state, if new one is STALE.
1040          */
1041         err = 0;
1042         update_isrouter = flags & NEIGH_UPDATE_F_OVERRIDE_ISROUTER;
1043         if (old & NUD_VALID) {
1044                 if (lladdr != neigh->ha && !(flags & NEIGH_UPDATE_F_OVERRIDE)) {
1045                         update_isrouter = 0;
1046                         if ((flags & NEIGH_UPDATE_F_WEAK_OVERRIDE) &&
1047                             (old & NUD_CONNECTED)) {
1048                                 lladdr = neigh->ha;
1049                                 new = NUD_STALE;
1050                         } else
1051                                 goto out;
1052                 } else {
1053                         if (lladdr == neigh->ha && new == NUD_STALE &&
1054                             ((flags & NEIGH_UPDATE_F_WEAK_OVERRIDE) ||
1055                              (old & NUD_CONNECTED))
1056                             )
1057                                 new = old;
1058                 }
1059         }
1060
1061         if (new != old) {
1062                 neigh_del_timer(neigh);
1063                 if (new & NUD_IN_TIMER)
1064                         neigh_add_timer(neigh, (jiffies +
1065                                                 ((new & NUD_REACHABLE) ?
1066                                                  neigh->parms->reachable_time :
1067                                                  0)));
1068                 neigh->nud_state = new;
1069         }
1070
1071         if (lladdr != neigh->ha) {
1072                 memcpy(&neigh->ha, lladdr, dev->addr_len);
1073                 neigh_update_hhs(neigh);
1074                 if (!(new & NUD_CONNECTED))
1075                         neigh->confirmed = jiffies -
1076                                       (neigh->parms->base_reachable_time << 1);
1077                 notify = 1;
1078         }
1079         if (new == old)
1080                 goto out;
1081         if (new & NUD_CONNECTED)
1082                 neigh_connect(neigh);
1083         else
1084                 neigh_suspect(neigh);
1085         if (!(old & NUD_VALID)) {
1086                 struct sk_buff *skb;
1087
1088                 /* Again: avoid dead loop if something went wrong */
1089
1090                 while (neigh->nud_state & NUD_VALID &&
1091                        (skb = __skb_dequeue(&neigh->arp_queue)) != NULL) {
1092                         struct neighbour *n1 = neigh;
1093                         write_unlock_bh(&neigh->lock);
1094                         /* On shaper/eql skb->dst->neighbour != neigh :( */
1095                         if (skb->dst && skb->dst->neighbour)
1096                                 n1 = skb->dst->neighbour;
1097                         n1->output(skb);
1098                         write_lock_bh(&neigh->lock);
1099                 }
1100                 skb_queue_purge(&neigh->arp_queue);
1101         }
1102 out:
1103         if (update_isrouter) {
1104                 neigh->flags = (flags & NEIGH_UPDATE_F_ISROUTER) ?
1105                         (neigh->flags | NTF_ROUTER) :
1106                         (neigh->flags & ~NTF_ROUTER);
1107         }
1108         write_unlock_bh(&neigh->lock);
1109
1110         if (notify)
1111                 neigh_update_notify(neigh);
1112
1113         return err;
1114 }
1115 EXPORT_SYMBOL(neigh_update);
1116
1117 struct neighbour *neigh_event_ns(struct neigh_table *tbl,
1118                                  u8 *lladdr, void *saddr,
1119                                  struct net_device *dev)
1120 {
1121         struct neighbour *neigh = __neigh_lookup(tbl, saddr, dev,
1122                                                  lladdr || !dev->addr_len);
1123         if (neigh)
1124                 neigh_update(neigh, lladdr, NUD_STALE,
1125                              NEIGH_UPDATE_F_OVERRIDE);
1126         return neigh;
1127 }
1128 EXPORT_SYMBOL(neigh_event_ns);
1129
1130 static void neigh_hh_init(struct neighbour *n, struct dst_entry *dst,
1131                           __be16 protocol)
1132 {
1133         struct hh_cache *hh;
1134         struct net_device *dev = dst->dev;
1135
1136         for (hh = n->hh; hh; hh = hh->hh_next)
1137                 if (hh->hh_type == protocol)
1138                         break;
1139
1140         if (!hh && (hh = kzalloc(sizeof(*hh), GFP_ATOMIC)) != NULL) {
1141                 seqlock_init(&hh->hh_lock);
1142                 hh->hh_type = protocol;
1143                 atomic_set(&hh->hh_refcnt, 0);
1144                 hh->hh_next = NULL;
1145
1146                 if (dev->header_ops->cache(n, hh)) {
1147                         kfree(hh);
1148                         hh = NULL;
1149                 } else {
1150                         atomic_inc(&hh->hh_refcnt);
1151                         hh->hh_next = n->hh;
1152                         n->hh       = hh;
1153                         if (n->nud_state & NUD_CONNECTED)
1154                                 hh->hh_output = n->ops->hh_output;
1155                         else
1156                                 hh->hh_output = n->ops->output;
1157                 }
1158         }
1159         if (hh) {
1160                 atomic_inc(&hh->hh_refcnt);
1161                 dst->hh = hh;
1162         }
1163 }
1164
1165 /* This function can be used in contexts, where only old dev_queue_xmit
1166    worked, f.e. if you want to override normal output path (eql, shaper),
1167    but resolution is not made yet.
1168  */
1169
1170 int neigh_compat_output(struct sk_buff *skb)
1171 {
1172         struct net_device *dev = skb->dev;
1173
1174         __skb_pull(skb, skb_network_offset(skb));
1175
1176         if (dev_hard_header(skb, dev, ntohs(skb->protocol), NULL, NULL,
1177                             skb->len) < 0 &&
1178             dev->header_ops->rebuild(skb))
1179                 return 0;
1180
1181         return dev_queue_xmit(skb);
1182 }
1183 EXPORT_SYMBOL(neigh_compat_output);
1184
1185 /* Slow and careful. */
1186
1187 int neigh_resolve_output(struct sk_buff *skb)
1188 {
1189         struct dst_entry *dst = skb->dst;
1190         struct neighbour *neigh;
1191         int rc = 0;
1192
1193         if (!dst || !(neigh = dst->neighbour))
1194                 goto discard;
1195
1196         __skb_pull(skb, skb_network_offset(skb));
1197
1198         if (!neigh_event_send(neigh, skb)) {
1199                 int err;
1200                 struct net_device *dev = neigh->dev;
1201                 if (dev->header_ops->cache && !dst->hh) {
1202                         write_lock_bh(&neigh->lock);
1203                         if (!dst->hh)
1204                                 neigh_hh_init(neigh, dst, dst->ops->protocol);
1205                         err = dev_hard_header(skb, dev, ntohs(skb->protocol),
1206                                               neigh->ha, NULL, skb->len);
1207                         write_unlock_bh(&neigh->lock);
1208                 } else {
1209                         read_lock_bh(&neigh->lock);
1210                         err = dev_hard_header(skb, dev, ntohs(skb->protocol),
1211                                               neigh->ha, NULL, skb->len);
1212                         read_unlock_bh(&neigh->lock);
1213                 }
1214                 if (err >= 0)
1215                         rc = neigh->ops->queue_xmit(skb);
1216                 else
1217                         goto out_kfree_skb;
1218         }
1219 out:
1220         return rc;
1221 discard:
1222         NEIGH_PRINTK1("neigh_resolve_output: dst=%p neigh=%p\n",
1223                       dst, dst ? dst->neighbour : NULL);
1224 out_kfree_skb:
1225         rc = -EINVAL;
1226         kfree_skb(skb);
1227         goto out;
1228 }
1229 EXPORT_SYMBOL(neigh_resolve_output);
1230
1231 /* As fast as possible without hh cache */
1232
1233 int neigh_connected_output(struct sk_buff *skb)
1234 {
1235         int err;
1236         struct dst_entry *dst = skb->dst;
1237         struct neighbour *neigh = dst->neighbour;
1238         struct net_device *dev = neigh->dev;
1239
1240         __skb_pull(skb, skb_network_offset(skb));
1241
1242         read_lock_bh(&neigh->lock);
1243         err = dev_hard_header(skb, dev, ntohs(skb->protocol),
1244                               neigh->ha, NULL, skb->len);
1245         read_unlock_bh(&neigh->lock);
1246         if (err >= 0)
1247                 err = neigh->ops->queue_xmit(skb);
1248         else {
1249                 err = -EINVAL;
1250                 kfree_skb(skb);
1251         }
1252         return err;
1253 }
1254 EXPORT_SYMBOL(neigh_connected_output);
1255
1256 static void neigh_proxy_process(unsigned long arg)
1257 {
1258         struct neigh_table *tbl = (struct neigh_table *)arg;
1259         long sched_next = 0;
1260         unsigned long now = jiffies;
1261         struct sk_buff *skb;
1262
1263         spin_lock(&tbl->proxy_queue.lock);
1264
1265         skb = tbl->proxy_queue.next;
1266
1267         while (skb != (struct sk_buff *)&tbl->proxy_queue) {
1268                 struct sk_buff *back = skb;
1269                 long tdif = NEIGH_CB(back)->sched_next - now;
1270
1271                 skb = skb->next;
1272                 if (tdif <= 0) {
1273                         struct net_device *dev = back->dev;
1274                         __skb_unlink(back, &tbl->proxy_queue);
1275                         if (tbl->proxy_redo && netif_running(dev))
1276                                 tbl->proxy_redo(back);
1277                         else
1278                                 kfree_skb(back);
1279
1280                         dev_put(dev);
1281                 } else if (!sched_next || tdif < sched_next)
1282                         sched_next = tdif;
1283         }
1284         del_timer(&tbl->proxy_timer);
1285         if (sched_next)
1286                 mod_timer(&tbl->proxy_timer, jiffies + sched_next);
1287         spin_unlock(&tbl->proxy_queue.lock);
1288 }
1289
1290 void pneigh_enqueue(struct neigh_table *tbl, struct neigh_parms *p,
1291                     struct sk_buff *skb)
1292 {
1293         unsigned long now = jiffies;
1294         unsigned long sched_next = now + (net_random() % p->proxy_delay);
1295
1296         if (tbl->proxy_queue.qlen > p->proxy_qlen) {
1297                 kfree_skb(skb);
1298                 return;
1299         }
1300
1301         NEIGH_CB(skb)->sched_next = sched_next;
1302         NEIGH_CB(skb)->flags |= LOCALLY_ENQUEUED;
1303
1304         spin_lock(&tbl->proxy_queue.lock);
1305         if (del_timer(&tbl->proxy_timer)) {
1306                 if (time_before(tbl->proxy_timer.expires, sched_next))
1307                         sched_next = tbl->proxy_timer.expires;
1308         }
1309         dst_release(skb->dst);
1310         skb->dst = NULL;
1311         dev_hold(skb->dev);
1312         __skb_queue_tail(&tbl->proxy_queue, skb);
1313         mod_timer(&tbl->proxy_timer, sched_next);
1314         spin_unlock(&tbl->proxy_queue.lock);
1315 }
1316 EXPORT_SYMBOL(pneigh_enqueue);
1317
1318 static inline struct neigh_parms *lookup_neigh_params(struct neigh_table *tbl,
1319                                                       struct net *net, int ifindex)
1320 {
1321         struct neigh_parms *p;
1322
1323         for (p = &tbl->parms; p; p = p->next) {
1324                 if ((p->dev && p->dev->ifindex == ifindex && net_eq(neigh_parms_net(p), net)) ||
1325                     (!p->dev && !ifindex))
1326                         return p;
1327         }
1328
1329         return NULL;
1330 }
1331
1332 struct neigh_parms *neigh_parms_alloc(struct net_device *dev,
1333                                       struct neigh_table *tbl)
1334 {
1335         struct neigh_parms *p, *ref;
1336         struct net *net;
1337
1338         net = dev_net(dev);
1339         ref = lookup_neigh_params(tbl, net, 0);
1340         if (!ref)
1341                 return NULL;
1342
1343         p = kmemdup(ref, sizeof(*p), GFP_KERNEL);
1344         if (p) {
1345                 p->tbl            = tbl;
1346                 atomic_set(&p->refcnt, 1);
1347                 INIT_RCU_HEAD(&p->rcu_head);
1348                 p->reachable_time =
1349                                 neigh_rand_reach_time(p->base_reachable_time);
1350
1351                 if (dev->neigh_setup && dev->neigh_setup(dev, p)) {
1352                         kfree(p);
1353                         return NULL;
1354                 }
1355
1356                 dev_hold(dev);
1357                 p->dev = dev;
1358 #ifdef CONFIG_NET_NS
1359                 p->net = hold_net(net);
1360 #endif
1361                 p->sysctl_table = NULL;
1362                 write_lock_bh(&tbl->lock);
1363                 p->next         = tbl->parms.next;
1364                 tbl->parms.next = p;
1365                 write_unlock_bh(&tbl->lock);
1366         }
1367         return p;
1368 }
1369 EXPORT_SYMBOL(neigh_parms_alloc);
1370
1371 static void neigh_rcu_free_parms(struct rcu_head *head)
1372 {
1373         struct neigh_parms *parms =
1374                 container_of(head, struct neigh_parms, rcu_head);
1375
1376         neigh_parms_put(parms);
1377 }
1378
1379 void neigh_parms_release(struct neigh_table *tbl, struct neigh_parms *parms)
1380 {
1381         struct neigh_parms **p;
1382
1383         if (!parms || parms == &tbl->parms)
1384                 return;
1385         write_lock_bh(&tbl->lock);
1386         for (p = &tbl->parms.next; *p; p = &(*p)->next) {
1387                 if (*p == parms) {
1388                         *p = parms->next;
1389                         parms->dead = 1;
1390                         write_unlock_bh(&tbl->lock);
1391                         if (parms->dev)
1392                                 dev_put(parms->dev);
1393                         call_rcu(&parms->rcu_head, neigh_rcu_free_parms);
1394                         return;
1395                 }
1396         }
1397         write_unlock_bh(&tbl->lock);
1398         NEIGH_PRINTK1("neigh_parms_release: not found\n");
1399 }
1400 EXPORT_SYMBOL(neigh_parms_release);
1401
1402 static void neigh_parms_destroy(struct neigh_parms *parms)
1403 {
1404         release_net(neigh_parms_net(parms));
1405         kfree(parms);
1406 }
1407
1408 static struct lock_class_key neigh_table_proxy_queue_class;
1409
1410 void neigh_table_init_no_netlink(struct neigh_table *tbl)
1411 {
1412         unsigned long now = jiffies;
1413         unsigned long phsize;
1414
1415 #ifdef CONFIG_NET_NS
1416         tbl->parms.net = &init_net;
1417 #endif
1418         atomic_set(&tbl->parms.refcnt, 1);
1419         INIT_RCU_HEAD(&tbl->parms.rcu_head);
1420         tbl->parms.reachable_time =
1421                           neigh_rand_reach_time(tbl->parms.base_reachable_time);
1422
1423         if (!tbl->kmem_cachep)
1424                 tbl->kmem_cachep =
1425                         kmem_cache_create(tbl->id, tbl->entry_size, 0,
1426                                           SLAB_HWCACHE_ALIGN|SLAB_PANIC,
1427                                           NULL);
1428         tbl->stats = alloc_percpu(struct neigh_statistics);
1429         if (!tbl->stats)
1430                 panic("cannot create neighbour cache statistics");
1431
1432 #ifdef CONFIG_PROC_FS
1433         tbl->pde = proc_create_data(tbl->id, 0, init_net.proc_net_stat,
1434                                     &neigh_stat_seq_fops, tbl);
1435         if (!tbl->pde)
1436                 panic("cannot create neighbour proc dir entry");
1437 #endif
1438
1439         tbl->hash_mask = 1;
1440         tbl->hash_buckets = neigh_hash_alloc(tbl->hash_mask + 1);
1441
1442         phsize = (PNEIGH_HASHMASK + 1) * sizeof(struct pneigh_entry *);
1443         tbl->phash_buckets = kzalloc(phsize, GFP_KERNEL);
1444
1445         if (!tbl->hash_buckets || !tbl->phash_buckets)
1446                 panic("cannot allocate neighbour cache hashes");
1447
1448         get_random_bytes(&tbl->hash_rnd, sizeof(tbl->hash_rnd));
1449
1450         rwlock_init(&tbl->lock);
1451         setup_timer(&tbl->gc_timer, neigh_periodic_timer, (unsigned long)tbl);
1452         tbl->gc_timer.expires  = now + 1;
1453         add_timer(&tbl->gc_timer);
1454
1455         setup_timer(&tbl->proxy_timer, neigh_proxy_process, (unsigned long)tbl);
1456         skb_queue_head_init_class(&tbl->proxy_queue,
1457                         &neigh_table_proxy_queue_class);
1458
1459         tbl->last_flush = now;
1460         tbl->last_rand  = now + tbl->parms.reachable_time * 20;
1461 }
1462 EXPORT_SYMBOL(neigh_table_init_no_netlink);
1463
1464 void neigh_table_init(struct neigh_table *tbl)
1465 {
1466         struct neigh_table *tmp;
1467
1468         neigh_table_init_no_netlink(tbl);
1469         write_lock(&neigh_tbl_lock);
1470         for (tmp = neigh_tables; tmp; tmp = tmp->next) {
1471                 if (tmp->family == tbl->family)
1472                         break;
1473         }
1474         tbl->next       = neigh_tables;
1475         neigh_tables    = tbl;
1476         write_unlock(&neigh_tbl_lock);
1477
1478         if (unlikely(tmp)) {
1479                 printk(KERN_ERR "NEIGH: Registering multiple tables for "
1480                        "family %d\n", tbl->family);
1481                 dump_stack();
1482         }
1483 }
1484 EXPORT_SYMBOL(neigh_table_init);
1485
1486 int neigh_table_clear(struct neigh_table *tbl)
1487 {
1488         struct neigh_table **tp;
1489
1490         /* It is not clean... Fix it to unload IPv6 module safely */
1491         del_timer_sync(&tbl->gc_timer);
1492         del_timer_sync(&tbl->proxy_timer);
1493         pneigh_queue_purge(&tbl->proxy_queue);
1494         neigh_ifdown(tbl, NULL);
1495         if (atomic_read(&tbl->entries))
1496                 printk(KERN_CRIT "neighbour leakage\n");
1497         write_lock(&neigh_tbl_lock);
1498         for (tp = &neigh_tables; *tp; tp = &(*tp)->next) {
1499                 if (*tp == tbl) {
1500                         *tp = tbl->next;
1501                         break;
1502                 }
1503         }
1504         write_unlock(&neigh_tbl_lock);
1505
1506         neigh_hash_free(tbl->hash_buckets, tbl->hash_mask + 1);
1507         tbl->hash_buckets = NULL;
1508
1509         kfree(tbl->phash_buckets);
1510         tbl->phash_buckets = NULL;
1511
1512         remove_proc_entry(tbl->id, init_net.proc_net_stat);
1513
1514         free_percpu(tbl->stats);
1515         tbl->stats = NULL;
1516
1517         kmem_cache_destroy(tbl->kmem_cachep);
1518         tbl->kmem_cachep = NULL;
1519
1520         return 0;
1521 }
1522 EXPORT_SYMBOL(neigh_table_clear);
1523
1524 static int neigh_delete(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
1525 {
1526         struct net *net = sock_net(skb->sk);
1527         struct ndmsg *ndm;
1528         struct nlattr *dst_attr;
1529         struct neigh_table *tbl;
1530         struct net_device *dev = NULL;
1531         int err = -EINVAL;
1532
1533         if (nlmsg_len(nlh) < sizeof(*ndm))
1534                 goto out;
1535
1536         dst_attr = nlmsg_find_attr(nlh, sizeof(*ndm), NDA_DST);
1537         if (dst_attr == NULL)
1538                 goto out;
1539
1540         ndm = nlmsg_data(nlh);
1541         if (ndm->ndm_ifindex) {
1542                 dev = dev_get_by_index(net, ndm->ndm_ifindex);
1543                 if (dev == NULL) {
1544                         err = -ENODEV;
1545                         goto out;
1546                 }
1547         }
1548
1549         read_lock(&neigh_tbl_lock);
1550         for (tbl = neigh_tables; tbl; tbl = tbl->next) {
1551                 struct neighbour *neigh;
1552
1553                 if (tbl->family != ndm->ndm_family)
1554                         continue;
1555                 read_unlock(&neigh_tbl_lock);
1556
1557                 if (nla_len(dst_attr) < tbl->key_len)
1558                         goto out_dev_put;
1559
1560                 if (ndm->ndm_flags & NTF_PROXY) {
1561                         err = pneigh_delete(tbl, net, nla_data(dst_attr), dev);
1562                         goto out_dev_put;
1563                 }
1564
1565                 if (dev == NULL)
1566                         goto out_dev_put;
1567
1568                 neigh = neigh_lookup(tbl, nla_data(dst_attr), dev);
1569                 if (neigh == NULL) {
1570                         err = -ENOENT;
1571                         goto out_dev_put;
1572                 }
1573
1574                 err = neigh_update(neigh, NULL, NUD_FAILED,
1575                                    NEIGH_UPDATE_F_OVERRIDE |
1576                                    NEIGH_UPDATE_F_ADMIN);
1577                 neigh_release(neigh);
1578                 goto out_dev_put;
1579         }
1580         read_unlock(&neigh_tbl_lock);
1581         err = -EAFNOSUPPORT;
1582
1583 out_dev_put:
1584         if (dev)
1585                 dev_put(dev);
1586 out:
1587         return err;
1588 }
1589
1590 static int neigh_add(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
1591 {
1592         struct net *net = sock_net(skb->sk);
1593         struct ndmsg *ndm;
1594         struct nlattr *tb[NDA_MAX+1];
1595         struct neigh_table *tbl;
1596         struct net_device *dev = NULL;
1597         int err;
1598
1599         err = nlmsg_parse(nlh, sizeof(*ndm), tb, NDA_MAX, NULL);
1600         if (err < 0)
1601                 goto out;
1602
1603         err = -EINVAL;
1604         if (tb[NDA_DST] == NULL)
1605                 goto out;
1606
1607         ndm = nlmsg_data(nlh);
1608         if (ndm->ndm_ifindex) {
1609                 dev = dev_get_by_index(net, ndm->ndm_ifindex);
1610                 if (dev == NULL) {
1611                         err = -ENODEV;
1612                         goto out;
1613                 }
1614
1615                 if (tb[NDA_LLADDR] && nla_len(tb[NDA_LLADDR]) < dev->addr_len)
1616                         goto out_dev_put;
1617         }
1618
1619         read_lock(&neigh_tbl_lock);
1620         for (tbl = neigh_tables; tbl; tbl = tbl->next) {
1621                 int flags = NEIGH_UPDATE_F_ADMIN | NEIGH_UPDATE_F_OVERRIDE;
1622                 struct neighbour *neigh;
1623                 void *dst, *lladdr;
1624
1625                 if (tbl->family != ndm->ndm_family)
1626                         continue;
1627                 read_unlock(&neigh_tbl_lock);
1628
1629                 if (nla_len(tb[NDA_DST]) < tbl->key_len)
1630                         goto out_dev_put;
1631                 dst = nla_data(tb[NDA_DST]);
1632                 lladdr = tb[NDA_LLADDR] ? nla_data(tb[NDA_LLADDR]) : NULL;
1633
1634                 if (ndm->ndm_flags & NTF_PROXY) {
1635                         struct pneigh_entry *pn;
1636
1637                         err = -ENOBUFS;
1638                         pn = pneigh_lookup(tbl, net, dst, dev, 1);
1639                         if (pn) {
1640                                 pn->flags = ndm->ndm_flags;
1641                                 err = 0;
1642                         }
1643                         goto out_dev_put;
1644                 }
1645
1646                 if (dev == NULL)
1647                         goto out_dev_put;
1648
1649                 neigh = neigh_lookup(tbl, dst, dev);
1650                 if (neigh == NULL) {
1651                         if (!(nlh->nlmsg_flags & NLM_F_CREATE)) {
1652                                 err = -ENOENT;
1653                                 goto out_dev_put;
1654                         }
1655
1656                         neigh = __neigh_lookup_errno(tbl, dst, dev);
1657                         if (IS_ERR(neigh)) {
1658                                 err = PTR_ERR(neigh);
1659                                 goto out_dev_put;
1660                         }
1661                 } else {
1662                         if (nlh->nlmsg_flags & NLM_F_EXCL) {
1663                                 err = -EEXIST;
1664                                 neigh_release(neigh);
1665                                 goto out_dev_put;
1666                         }
1667
1668                         if (!(nlh->nlmsg_flags & NLM_F_REPLACE))
1669                                 flags &= ~NEIGH_UPDATE_F_OVERRIDE;
1670                 }
1671
1672                 err = neigh_update(neigh, lladdr, ndm->ndm_state, flags);
1673                 neigh_release(neigh);
1674                 goto out_dev_put;
1675         }
1676
1677         read_unlock(&neigh_tbl_lock);
1678         err = -EAFNOSUPPORT;
1679
1680 out_dev_put:
1681         if (dev)
1682                 dev_put(dev);
1683 out:
1684         return err;
1685 }
1686
1687 static int neightbl_fill_parms(struct sk_buff *skb, struct neigh_parms *parms)
1688 {
1689         struct nlattr *nest;
1690
1691         nest = nla_nest_start(skb, NDTA_PARMS);
1692         if (nest == NULL)
1693                 return -ENOBUFS;
1694
1695         if (parms->dev)
1696                 NLA_PUT_U32(skb, NDTPA_IFINDEX, parms->dev->ifindex);
1697
1698         NLA_PUT_U32(skb, NDTPA_REFCNT, atomic_read(&parms->refcnt));
1699         NLA_PUT_U32(skb, NDTPA_QUEUE_LEN, parms->queue_len);
1700         NLA_PUT_U32(skb, NDTPA_PROXY_QLEN, parms->proxy_qlen);
1701         NLA_PUT_U32(skb, NDTPA_APP_PROBES, parms->app_probes);
1702         NLA_PUT_U32(skb, NDTPA_UCAST_PROBES, parms->ucast_probes);
1703         NLA_PUT_U32(skb, NDTPA_MCAST_PROBES, parms->mcast_probes);
1704         NLA_PUT_MSECS(skb, NDTPA_REACHABLE_TIME, parms->reachable_time);
1705         NLA_PUT_MSECS(skb, NDTPA_BASE_REACHABLE_TIME,
1706                       parms->base_reachable_time);
1707         NLA_PUT_MSECS(skb, NDTPA_GC_STALETIME, parms->gc_staletime);
1708         NLA_PUT_MSECS(skb, NDTPA_DELAY_PROBE_TIME, parms->delay_probe_time);
1709         NLA_PUT_MSECS(skb, NDTPA_RETRANS_TIME, parms->retrans_time);
1710         NLA_PUT_MSECS(skb, NDTPA_ANYCAST_DELAY, parms->anycast_delay);
1711         NLA_PUT_MSECS(skb, NDTPA_PROXY_DELAY, parms->proxy_delay);
1712         NLA_PUT_MSECS(skb, NDTPA_LOCKTIME, parms->locktime);
1713
1714         return nla_nest_end(skb, nest);
1715
1716 nla_put_failure:
1717         return nla_nest_cancel(skb, nest);
1718 }
1719
1720 static int neightbl_fill_info(struct sk_buff *skb, struct neigh_table *tbl,
1721                               u32 pid, u32 seq, int type, int flags)
1722 {
1723         struct nlmsghdr *nlh;
1724         struct ndtmsg *ndtmsg;
1725
1726         nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndtmsg), flags);
1727         if (nlh == NULL)
1728                 return -EMSGSIZE;
1729
1730         ndtmsg = nlmsg_data(nlh);
1731
1732         read_lock_bh(&tbl->lock);
1733         ndtmsg->ndtm_family = tbl->family;
1734         ndtmsg->ndtm_pad1   = 0;
1735         ndtmsg->ndtm_pad2   = 0;
1736
1737         NLA_PUT_STRING(skb, NDTA_NAME, tbl->id);
1738         NLA_PUT_MSECS(skb, NDTA_GC_INTERVAL, tbl->gc_interval);
1739         NLA_PUT_U32(skb, NDTA_THRESH1, tbl->gc_thresh1);
1740         NLA_PUT_U32(skb, NDTA_THRESH2, tbl->gc_thresh2);
1741         NLA_PUT_U32(skb, NDTA_THRESH3, tbl->gc_thresh3);
1742
1743         {
1744                 unsigned long now = jiffies;
1745                 unsigned int flush_delta = now - tbl->last_flush;
1746                 unsigned int rand_delta = now - tbl->last_rand;
1747
1748                 struct ndt_config ndc = {
1749                         .ndtc_key_len           = tbl->key_len,
1750                         .ndtc_entry_size        = tbl->entry_size,
1751                         .ndtc_entries           = atomic_read(&tbl->entries),
1752                         .ndtc_last_flush        = jiffies_to_msecs(flush_delta),
1753                         .ndtc_last_rand         = jiffies_to_msecs(rand_delta),
1754                         .ndtc_hash_rnd          = tbl->hash_rnd,
1755                         .ndtc_hash_mask         = tbl->hash_mask,
1756                         .ndtc_hash_chain_gc     = tbl->hash_chain_gc,
1757                         .ndtc_proxy_qlen        = tbl->proxy_queue.qlen,
1758                 };
1759
1760                 NLA_PUT(skb, NDTA_CONFIG, sizeof(ndc), &ndc);
1761         }
1762
1763         {
1764                 int cpu;
1765                 struct ndt_stats ndst;
1766
1767                 memset(&ndst, 0, sizeof(ndst));
1768
1769                 for_each_possible_cpu(cpu) {
1770                         struct neigh_statistics *st;
1771
1772                         st = per_cpu_ptr(tbl->stats, cpu);
1773                         ndst.ndts_allocs                += st->allocs;
1774                         ndst.ndts_destroys              += st->destroys;
1775                         ndst.ndts_hash_grows            += st->hash_grows;
1776                         ndst.ndts_res_failed            += st->res_failed;
1777                         ndst.ndts_lookups               += st->lookups;
1778                         ndst.ndts_hits                  += st->hits;
1779                         ndst.ndts_rcv_probes_mcast      += st->rcv_probes_mcast;
1780                         ndst.ndts_rcv_probes_ucast      += st->rcv_probes_ucast;
1781                         ndst.ndts_periodic_gc_runs      += st->periodic_gc_runs;
1782                         ndst.ndts_forced_gc_runs        += st->forced_gc_runs;
1783                 }
1784
1785                 NLA_PUT(skb, NDTA_STATS, sizeof(ndst), &ndst);
1786         }
1787
1788         BUG_ON(tbl->parms.dev);
1789         if (neightbl_fill_parms(skb, &tbl->parms) < 0)
1790                 goto nla_put_failure;
1791
1792         read_unlock_bh(&tbl->lock);
1793         return nlmsg_end(skb, nlh);
1794
1795 nla_put_failure:
1796         read_unlock_bh(&tbl->lock);
1797         nlmsg_cancel(skb, nlh);
1798         return -EMSGSIZE;
1799 }
1800
1801 static int neightbl_fill_param_info(struct sk_buff *skb,
1802                                     struct neigh_table *tbl,
1803                                     struct neigh_parms *parms,
1804                                     u32 pid, u32 seq, int type,
1805                                     unsigned int flags)
1806 {
1807         struct ndtmsg *ndtmsg;
1808         struct nlmsghdr *nlh;
1809
1810         nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndtmsg), flags);
1811         if (nlh == NULL)
1812                 return -EMSGSIZE;
1813
1814         ndtmsg = nlmsg_data(nlh);
1815
1816         read_lock_bh(&tbl->lock);
1817         ndtmsg->ndtm_family = tbl->family;
1818         ndtmsg->ndtm_pad1   = 0;
1819         ndtmsg->ndtm_pad2   = 0;
1820
1821         if (nla_put_string(skb, NDTA_NAME, tbl->id) < 0 ||
1822             neightbl_fill_parms(skb, parms) < 0)
1823                 goto errout;
1824
1825         read_unlock_bh(&tbl->lock);
1826         return nlmsg_end(skb, nlh);
1827 errout:
1828         read_unlock_bh(&tbl->lock);
1829         nlmsg_cancel(skb, nlh);
1830         return -EMSGSIZE;
1831 }
1832
1833 static const struct nla_policy nl_neightbl_policy[NDTA_MAX+1] = {
1834         [NDTA_NAME]             = { .type = NLA_STRING },
1835         [NDTA_THRESH1]          = { .type = NLA_U32 },
1836         [NDTA_THRESH2]          = { .type = NLA_U32 },
1837         [NDTA_THRESH3]          = { .type = NLA_U32 },
1838         [NDTA_GC_INTERVAL]      = { .type = NLA_U64 },
1839         [NDTA_PARMS]            = { .type = NLA_NESTED },
1840 };
1841
1842 static const struct nla_policy nl_ntbl_parm_policy[NDTPA_MAX+1] = {
1843         [NDTPA_IFINDEX]                 = { .type = NLA_U32 },
1844         [NDTPA_QUEUE_LEN]               = { .type = NLA_U32 },
1845         [NDTPA_PROXY_QLEN]              = { .type = NLA_U32 },
1846         [NDTPA_APP_PROBES]              = { .type = NLA_U32 },
1847         [NDTPA_UCAST_PROBES]            = { .type = NLA_U32 },
1848         [NDTPA_MCAST_PROBES]            = { .type = NLA_U32 },
1849         [NDTPA_BASE_REACHABLE_TIME]     = { .type = NLA_U64 },
1850         [NDTPA_GC_STALETIME]            = { .type = NLA_U64 },
1851         [NDTPA_DELAY_PROBE_TIME]        = { .type = NLA_U64 },
1852         [NDTPA_RETRANS_TIME]            = { .type = NLA_U64 },
1853         [NDTPA_ANYCAST_DELAY]           = { .type = NLA_U64 },
1854         [NDTPA_PROXY_DELAY]             = { .type = NLA_U64 },
1855         [NDTPA_LOCKTIME]                = { .type = NLA_U64 },
1856 };
1857
1858 static int neightbl_set(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
1859 {
1860         struct net *net = sock_net(skb->sk);
1861         struct neigh_table *tbl;
1862         struct ndtmsg *ndtmsg;
1863         struct nlattr *tb[NDTA_MAX+1];
1864         int err;
1865
1866         err = nlmsg_parse(nlh, sizeof(*ndtmsg), tb, NDTA_MAX,
1867                           nl_neightbl_policy);
1868         if (err < 0)
1869                 goto errout;
1870
1871         if (tb[NDTA_NAME] == NULL) {
1872                 err = -EINVAL;
1873                 goto errout;
1874         }
1875
1876         ndtmsg = nlmsg_data(nlh);
1877         read_lock(&neigh_tbl_lock);
1878         for (tbl = neigh_tables; tbl; tbl = tbl->next) {
1879                 if (ndtmsg->ndtm_family && tbl->family != ndtmsg->ndtm_family)
1880                         continue;
1881
1882                 if (nla_strcmp(tb[NDTA_NAME], tbl->id) == 0)
1883                         break;
1884         }
1885
1886         if (tbl == NULL) {
1887                 err = -ENOENT;
1888                 goto errout_locked;
1889         }
1890
1891         /*
1892          * We acquire tbl->lock to be nice to the periodic timers and
1893          * make sure they always see a consistent set of values.
1894          */
1895         write_lock_bh(&tbl->lock);
1896
1897         if (tb[NDTA_PARMS]) {
1898                 struct nlattr *tbp[NDTPA_MAX+1];
1899                 struct neigh_parms *p;
1900                 int i, ifindex = 0;
1901
1902                 err = nla_parse_nested(tbp, NDTPA_MAX, tb[NDTA_PARMS],
1903                                        nl_ntbl_parm_policy);
1904                 if (err < 0)
1905                         goto errout_tbl_lock;
1906
1907                 if (tbp[NDTPA_IFINDEX])
1908                         ifindex = nla_get_u32(tbp[NDTPA_IFINDEX]);
1909
1910                 p = lookup_neigh_params(tbl, net, ifindex);
1911                 if (p == NULL) {
1912                         err = -ENOENT;
1913                         goto errout_tbl_lock;
1914                 }
1915
1916                 for (i = 1; i <= NDTPA_MAX; i++) {
1917                         if (tbp[i] == NULL)
1918                                 continue;
1919
1920                         switch (i) {
1921                         case NDTPA_QUEUE_LEN:
1922                                 p->queue_len = nla_get_u32(tbp[i]);
1923                                 break;
1924                         case NDTPA_PROXY_QLEN:
1925                                 p->proxy_qlen = nla_get_u32(tbp[i]);
1926                                 break;
1927                         case NDTPA_APP_PROBES:
1928                                 p->app_probes = nla_get_u32(tbp[i]);
1929                                 break;
1930                         case NDTPA_UCAST_PROBES:
1931                                 p->ucast_probes = nla_get_u32(tbp[i]);
1932                                 break;
1933                         case NDTPA_MCAST_PROBES:
1934                                 p->mcast_probes = nla_get_u32(tbp[i]);
1935                                 break;
1936                         case NDTPA_BASE_REACHABLE_TIME:
1937                                 p->base_reachable_time = nla_get_msecs(tbp[i]);
1938                                 break;
1939                         case NDTPA_GC_STALETIME:
1940                                 p->gc_staletime = nla_get_msecs(tbp[i]);
1941                                 break;
1942                         case NDTPA_DELAY_PROBE_TIME:
1943                                 p->delay_probe_time = nla_get_msecs(tbp[i]);
1944                                 break;
1945                         case NDTPA_RETRANS_TIME:
1946                                 p->retrans_time = nla_get_msecs(tbp[i]);
1947                                 break;
1948                         case NDTPA_ANYCAST_DELAY:
1949                                 p->anycast_delay = nla_get_msecs(tbp[i]);
1950                                 break;
1951                         case NDTPA_PROXY_DELAY:
1952                                 p->proxy_delay = nla_get_msecs(tbp[i]);
1953                                 break;
1954                         case NDTPA_LOCKTIME:
1955                                 p->locktime = nla_get_msecs(tbp[i]);
1956                                 break;
1957                         }
1958                 }
1959         }
1960
1961         if (tb[NDTA_THRESH1])
1962                 tbl->gc_thresh1 = nla_get_u32(tb[NDTA_THRESH1]);
1963
1964         if (tb[NDTA_THRESH2])
1965                 tbl->gc_thresh2 = nla_get_u32(tb[NDTA_THRESH2]);
1966
1967         if (tb[NDTA_THRESH3])
1968                 tbl->gc_thresh3 = nla_get_u32(tb[NDTA_THRESH3]);
1969
1970         if (tb[NDTA_GC_INTERVAL])
1971                 tbl->gc_interval = nla_get_msecs(tb[NDTA_GC_INTERVAL]);
1972
1973         err = 0;
1974
1975 errout_tbl_lock:
1976         write_unlock_bh(&tbl->lock);
1977 errout_locked:
1978         read_unlock(&neigh_tbl_lock);
1979 errout:
1980         return err;
1981 }
1982
1983 static int neightbl_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
1984 {
1985         struct net *net = sock_net(skb->sk);
1986         int family, tidx, nidx = 0;
1987         int tbl_skip = cb->args[0];
1988         int neigh_skip = cb->args[1];
1989         struct neigh_table *tbl;
1990
1991         family = ((struct rtgenmsg *) nlmsg_data(cb->nlh))->rtgen_family;
1992
1993         read_lock(&neigh_tbl_lock);
1994         for (tbl = neigh_tables, tidx = 0; tbl; tbl = tbl->next, tidx++) {
1995                 struct neigh_parms *p;
1996
1997                 if (tidx < tbl_skip || (family && tbl->family != family))
1998                         continue;
1999
2000                 if (neightbl_fill_info(skb, tbl, NETLINK_CB(cb->skb).pid,
2001                                        cb->nlh->nlmsg_seq, RTM_NEWNEIGHTBL,
2002                                        NLM_F_MULTI) <= 0)
2003                         break;
2004
2005                 for (nidx = 0, p = tbl->parms.next; p; p = p->next) {
2006                         if (!net_eq(neigh_parms_net(p), net))
2007                                 continue;
2008
2009                         if (nidx++ < neigh_skip)
2010                                 continue;
2011
2012                         if (neightbl_fill_param_info(skb, tbl, p,
2013                                                      NETLINK_CB(cb->skb).pid,
2014                                                      cb->nlh->nlmsg_seq,
2015                                                      RTM_NEWNEIGHTBL,
2016                                                      NLM_F_MULTI) <= 0)
2017                                 goto out;
2018                 }
2019
2020                 neigh_skip = 0;
2021         }
2022 out:
2023         read_unlock(&neigh_tbl_lock);
2024         cb->args[0] = tidx;
2025         cb->args[1] = nidx;
2026
2027         return skb->len;
2028 }
2029
2030 static int neigh_fill_info(struct sk_buff *skb, struct neighbour *neigh,
2031                            u32 pid, u32 seq, int type, unsigned int flags)
2032 {
2033         unsigned long now = jiffies;
2034         struct nda_cacheinfo ci;
2035         struct nlmsghdr *nlh;
2036         struct ndmsg *ndm;
2037
2038         nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndm), flags);
2039         if (nlh == NULL)
2040                 return -EMSGSIZE;
2041
2042         ndm = nlmsg_data(nlh);
2043         ndm->ndm_family  = neigh->ops->family;
2044         ndm->ndm_pad1    = 0;
2045         ndm->ndm_pad2    = 0;
2046         ndm->ndm_flags   = neigh->flags;
2047         ndm->ndm_type    = neigh->type;
2048         ndm->ndm_ifindex = neigh->dev->ifindex;
2049
2050         NLA_PUT(skb, NDA_DST, neigh->tbl->key_len, neigh->primary_key);
2051
2052         read_lock_bh(&neigh->lock);
2053         ndm->ndm_state   = neigh->nud_state;
2054         if ((neigh->nud_state & NUD_VALID) &&
2055             nla_put(skb, NDA_LLADDR, neigh->dev->addr_len, neigh->ha) < 0) {
2056                 read_unlock_bh(&neigh->lock);
2057                 goto nla_put_failure;
2058         }
2059
2060         ci.ndm_used      = now - neigh->used;
2061         ci.ndm_confirmed = now - neigh->confirmed;
2062         ci.ndm_updated   = now - neigh->updated;
2063         ci.ndm_refcnt    = atomic_read(&neigh->refcnt) - 1;
2064         read_unlock_bh(&neigh->lock);
2065
2066         NLA_PUT_U32(skb, NDA_PROBES, atomic_read(&neigh->probes));
2067         NLA_PUT(skb, NDA_CACHEINFO, sizeof(ci), &ci);
2068
2069         return nlmsg_end(skb, nlh);
2070
2071 nla_put_failure:
2072         nlmsg_cancel(skb, nlh);
2073         return -EMSGSIZE;
2074 }
2075
2076 static void neigh_update_notify(struct neighbour *neigh)
2077 {
2078         call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, neigh);
2079         __neigh_notify(neigh, RTM_NEWNEIGH, 0);
2080 }
2081
2082 static int neigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb,
2083                             struct netlink_callback *cb)
2084 {
2085         struct net * net = sock_net(skb->sk);
2086         struct neighbour *n;
2087         int rc, h, s_h = cb->args[1];
2088         int idx, s_idx = idx = cb->args[2];
2089
2090         read_lock_bh(&tbl->lock);
2091         for (h = 0; h <= tbl->hash_mask; h++) {
2092                 if (h < s_h)
2093                         continue;
2094                 if (h > s_h)
2095                         s_idx = 0;
2096                 for (n = tbl->hash_buckets[h], idx = 0; n; n = n->next) {
2097                         int lidx;
2098                         if (dev_net(n->dev) != net)
2099                                 continue;
2100                         lidx = idx++;
2101                         if (lidx < s_idx)
2102                                 continue;
2103                         if (neigh_fill_info(skb, n, NETLINK_CB(cb->skb).pid,
2104                                             cb->nlh->nlmsg_seq,
2105                                             RTM_NEWNEIGH,
2106                                             NLM_F_MULTI) <= 0) {
2107                                 read_unlock_bh(&tbl->lock);
2108                                 rc = -1;
2109                                 goto out;
2110                         }
2111                 }
2112         }
2113         read_unlock_bh(&tbl->lock);
2114         rc = skb->len;
2115 out:
2116         cb->args[1] = h;
2117         cb->args[2] = idx;
2118         return rc;
2119 }
2120
2121 static int neigh_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
2122 {
2123         struct neigh_table *tbl;
2124         int t, family, s_t;
2125
2126         read_lock(&neigh_tbl_lock);
2127         family = ((struct rtgenmsg *) nlmsg_data(cb->nlh))->rtgen_family;
2128         s_t = cb->args[0];
2129
2130         for (tbl = neigh_tables, t = 0; tbl; tbl = tbl->next, t++) {
2131                 if (t < s_t || (family && tbl->family != family))
2132                         continue;
2133                 if (t > s_t)
2134                         memset(&cb->args[1], 0, sizeof(cb->args) -
2135                                                 sizeof(cb->args[0]));
2136                 if (neigh_dump_table(tbl, skb, cb) < 0)
2137                         break;
2138         }
2139         read_unlock(&neigh_tbl_lock);
2140
2141         cb->args[0] = t;
2142         return skb->len;
2143 }
2144
2145 void neigh_for_each(struct neigh_table *tbl, void (*cb)(struct neighbour *, void *), void *cookie)
2146 {
2147         int chain;
2148
2149         read_lock_bh(&tbl->lock);
2150         for (chain = 0; chain <= tbl->hash_mask; chain++) {
2151                 struct neighbour *n;
2152
2153                 for (n = tbl->hash_buckets[chain]; n; n = n->next)
2154                         cb(n, cookie);
2155         }
2156         read_unlock_bh(&tbl->lock);
2157 }
2158 EXPORT_SYMBOL(neigh_for_each);
2159
2160 /* The tbl->lock must be held as a writer and BH disabled. */
2161 void __neigh_for_each_release(struct neigh_table *tbl,
2162                               int (*cb)(struct neighbour *))
2163 {
2164         int chain;
2165
2166         for (chain = 0; chain <= tbl->hash_mask; chain++) {
2167                 struct neighbour *n, **np;
2168
2169                 np = &tbl->hash_buckets[chain];
2170                 while ((n = *np) != NULL) {
2171                         int release;
2172
2173                         write_lock(&n->lock);
2174                         release = cb(n);
2175                         if (release) {
2176                                 *np = n->next;
2177                                 n->dead = 1;
2178                         } else
2179                                 np = &n->next;
2180                         write_unlock(&n->lock);
2181                         if (release)
2182                                 neigh_cleanup_and_release(n);
2183                 }
2184         }
2185 }
2186 EXPORT_SYMBOL(__neigh_for_each_release);
2187
2188 #ifdef CONFIG_PROC_FS
2189
2190 static struct neighbour *neigh_get_first(struct seq_file *seq)
2191 {
2192         struct neigh_seq_state *state = seq->private;
2193         struct net *net = seq_file_net(seq);
2194         struct neigh_table *tbl = state->tbl;
2195         struct neighbour *n = NULL;
2196         int bucket = state->bucket;
2197
2198         state->flags &= ~NEIGH_SEQ_IS_PNEIGH;
2199         for (bucket = 0; bucket <= tbl->hash_mask; bucket++) {
2200                 n = tbl->hash_buckets[bucket];
2201
2202                 while (n) {
2203                         if (!net_eq(dev_net(n->dev), net))
2204                                 goto next;
2205                         if (state->neigh_sub_iter) {
2206                                 loff_t fakep = 0;
2207                                 void *v;
2208
2209                                 v = state->neigh_sub_iter(state, n, &fakep);
2210                                 if (!v)
2211                                         goto next;
2212                         }
2213                         if (!(state->flags & NEIGH_SEQ_SKIP_NOARP))
2214                                 break;
2215                         if (n->nud_state & ~NUD_NOARP)
2216                                 break;
2217                 next:
2218                         n = n->next;
2219                 }
2220
2221                 if (n)
2222                         break;
2223         }
2224         state->bucket = bucket;
2225
2226         return n;
2227 }
2228
2229 static struct neighbour *neigh_get_next(struct seq_file *seq,
2230                                         struct neighbour *n,
2231                                         loff_t *pos)
2232 {
2233         struct neigh_seq_state *state = seq->private;
2234         struct net *net = seq_file_net(seq);
2235         struct neigh_table *tbl = state->tbl;
2236
2237         if (state->neigh_sub_iter) {
2238                 void *v = state->neigh_sub_iter(state, n, pos);
2239                 if (v)
2240                         return n;
2241         }
2242         n = n->next;
2243
2244         while (1) {
2245                 while (n) {
2246                         if (!net_eq(dev_net(n->dev), net))
2247                                 goto next;
2248                         if (state->neigh_sub_iter) {
2249                                 void *v = state->neigh_sub_iter(state, n, pos);
2250                                 if (v)
2251                                         return n;
2252                                 goto next;
2253                         }
2254                         if (!(state->flags & NEIGH_SEQ_SKIP_NOARP))
2255                                 break;
2256
2257                         if (n->nud_state & ~NUD_NOARP)
2258                                 break;
2259                 next:
2260                         n = n->next;
2261                 }
2262
2263                 if (n)
2264                         break;
2265
2266                 if (++state->bucket > tbl->hash_mask)
2267                         break;
2268
2269                 n = tbl->hash_buckets[state->bucket];
2270         }
2271
2272         if (n && pos)
2273                 --(*pos);
2274         return n;
2275 }
2276
2277 static struct neighbour *neigh_get_idx(struct seq_file *seq, loff_t *pos)
2278 {
2279         struct neighbour *n = neigh_get_first(seq);
2280
2281         if (n) {
2282                 while (*pos) {
2283                         n = neigh_get_next(seq, n, pos);
2284                         if (!n)
2285                                 break;
2286                 }
2287         }
2288         return *pos ? NULL : n;
2289 }
2290
2291 static struct pneigh_entry *pneigh_get_first(struct seq_file *seq)
2292 {
2293         struct neigh_seq_state *state = seq->private;
2294         struct net *net = seq_file_net(seq);
2295         struct neigh_table *tbl = state->tbl;
2296         struct pneigh_entry *pn = NULL;
2297         int bucket = state->bucket;
2298
2299         state->flags |= NEIGH_SEQ_IS_PNEIGH;
2300         for (bucket = 0; bucket <= PNEIGH_HASHMASK; bucket++) {
2301                 pn = tbl->phash_buckets[bucket];
2302                 while (pn && !net_eq(pneigh_net(pn), net))
2303                         pn = pn->next;
2304                 if (pn)
2305                         break;
2306         }
2307         state->bucket = bucket;
2308
2309         return pn;
2310 }
2311
2312 static struct pneigh_entry *pneigh_get_next(struct seq_file *seq,
2313                                             struct pneigh_entry *pn,
2314                                             loff_t *pos)
2315 {
2316         struct neigh_seq_state *state = seq->private;
2317         struct net *net = seq_file_net(seq);
2318         struct neigh_table *tbl = state->tbl;
2319
2320         pn = pn->next;
2321         while (!pn) {
2322                 if (++state->bucket > PNEIGH_HASHMASK)
2323                         break;
2324                 pn = tbl->phash_buckets[state->bucket];
2325                 while (pn && !net_eq(pneigh_net(pn), net))
2326                         pn = pn->next;
2327                 if (pn)
2328                         break;
2329         }
2330
2331         if (pn && pos)
2332                 --(*pos);
2333
2334         return pn;
2335 }
2336
2337 static struct pneigh_entry *pneigh_get_idx(struct seq_file *seq, loff_t *pos)
2338 {
2339         struct pneigh_entry *pn = pneigh_get_first(seq);
2340
2341         if (pn) {
2342                 while (*pos) {
2343                         pn = pneigh_get_next(seq, pn, pos);
2344                         if (!pn)
2345                                 break;
2346                 }
2347         }
2348         return *pos ? NULL : pn;
2349 }
2350
2351 static void *neigh_get_idx_any(struct seq_file *seq, loff_t *pos)
2352 {
2353         struct neigh_seq_state *state = seq->private;
2354         void *rc;
2355
2356         rc = neigh_get_idx(seq, pos);
2357         if (!rc && !(state->flags & NEIGH_SEQ_NEIGH_ONLY))
2358                 rc = pneigh_get_idx(seq, pos);
2359
2360         return rc;
2361 }
2362
2363 void *neigh_seq_start(struct seq_file *seq, loff_t *pos, struct neigh_table *tbl, unsigned int neigh_seq_flags)
2364         __acquires(tbl->lock)
2365 {
2366         struct neigh_seq_state *state = seq->private;
2367         loff_t pos_minus_one;
2368
2369         state->tbl = tbl;
2370         state->bucket = 0;
2371         state->flags = (neigh_seq_flags & ~NEIGH_SEQ_IS_PNEIGH);
2372
2373         read_lock_bh(&tbl->lock);
2374
2375         pos_minus_one = *pos - 1;
2376         return *pos ? neigh_get_idx_any(seq, &pos_minus_one) : SEQ_START_TOKEN;
2377 }
2378 EXPORT_SYMBOL(neigh_seq_start);
2379
2380 void *neigh_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2381 {
2382         struct neigh_seq_state *state;
2383         void *rc;
2384
2385         if (v == SEQ_START_TOKEN) {
2386                 rc = neigh_get_idx(seq, pos);
2387                 goto out;
2388         }
2389
2390         state = seq->private;
2391         if (!(state->flags & NEIGH_SEQ_IS_PNEIGH)) {
2392                 rc = neigh_get_next(seq, v, NULL);
2393                 if (rc)
2394                         goto out;
2395                 if (!(state->flags & NEIGH_SEQ_NEIGH_ONLY))
2396                         rc = pneigh_get_first(seq);
2397         } else {
2398                 BUG_ON(state->flags & NEIGH_SEQ_NEIGH_ONLY);
2399                 rc = pneigh_get_next(seq, v, NULL);
2400         }
2401 out:
2402         ++(*pos);
2403         return rc;
2404 }
2405 EXPORT_SYMBOL(neigh_seq_next);
2406
2407 void neigh_seq_stop(struct seq_file *seq, void *v)
2408         __releases(tbl->lock)
2409 {
2410         struct neigh_seq_state *state = seq->private;
2411         struct neigh_table *tbl = state->tbl;
2412
2413         read_unlock_bh(&tbl->lock);
2414 }
2415 EXPORT_SYMBOL(neigh_seq_stop);
2416
2417 /* statistics via seq_file */
2418
2419 static void *neigh_stat_seq_start(struct seq_file *seq, loff_t *pos)
2420 {
2421         struct proc_dir_entry *pde = seq->private;
2422         struct neigh_table *tbl = pde->data;
2423         int cpu;
2424
2425         if (*pos == 0)
2426                 return SEQ_START_TOKEN;
2427
2428         for (cpu = *pos-1; cpu < NR_CPUS; ++cpu) {
2429                 if (!cpu_possible(cpu))
2430                         continue;
2431                 *pos = cpu+1;
2432                 return per_cpu_ptr(tbl->stats, cpu);
2433         }
2434         return NULL;
2435 }
2436
2437 static void *neigh_stat_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2438 {
2439         struct proc_dir_entry *pde = seq->private;
2440         struct neigh_table *tbl = pde->data;
2441         int cpu;
2442
2443         for (cpu = *pos; cpu < NR_CPUS; ++cpu) {
2444                 if (!cpu_possible(cpu))
2445                         continue;
2446                 *pos = cpu+1;
2447                 return per_cpu_ptr(tbl->stats, cpu);
2448         }
2449         return NULL;
2450 }
2451
2452 static void neigh_stat_seq_stop(struct seq_file *seq, void *v)
2453 {
2454
2455 }
2456
2457 static int neigh_stat_seq_show(struct seq_file *seq, void *v)
2458 {
2459         struct proc_dir_entry *pde = seq->private;
2460         struct neigh_table *tbl = pde->data;
2461         struct neigh_statistics *st = v;
2462
2463         if (v == SEQ_START_TOKEN) {
2464                 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");
2465                 return 0;
2466         }
2467
2468         seq_printf(seq, "%08x  %08lx %08lx %08lx  %08lx %08lx  %08lx  "
2469                         "%08lx %08lx  %08lx %08lx\n",
2470                    atomic_read(&tbl->entries),
2471
2472                    st->allocs,
2473                    st->destroys,
2474                    st->hash_grows,
2475
2476                    st->lookups,
2477                    st->hits,
2478
2479                    st->res_failed,
2480
2481                    st->rcv_probes_mcast,
2482                    st->rcv_probes_ucast,
2483
2484                    st->periodic_gc_runs,
2485                    st->forced_gc_runs
2486                    );
2487
2488         return 0;
2489 }
2490
2491 static const struct seq_operations neigh_stat_seq_ops = {
2492         .start  = neigh_stat_seq_start,
2493         .next   = neigh_stat_seq_next,
2494         .stop   = neigh_stat_seq_stop,
2495         .show   = neigh_stat_seq_show,
2496 };
2497
2498 static int neigh_stat_seq_open(struct inode *inode, struct file *file)
2499 {
2500         int ret = seq_open(file, &neigh_stat_seq_ops);
2501
2502         if (!ret) {
2503                 struct seq_file *sf = file->private_data;
2504                 sf->private = PDE(inode);
2505         }
2506         return ret;
2507 };
2508
2509 static const struct file_operations neigh_stat_seq_fops = {
2510         .owner   = THIS_MODULE,
2511         .open    = neigh_stat_seq_open,
2512         .read    = seq_read,
2513         .llseek  = seq_lseek,
2514         .release = seq_release,
2515 };
2516
2517 #endif /* CONFIG_PROC_FS */
2518
2519 static inline size_t neigh_nlmsg_size(void)
2520 {
2521         return NLMSG_ALIGN(sizeof(struct ndmsg))
2522                + nla_total_size(MAX_ADDR_LEN) /* NDA_DST */
2523                + nla_total_size(MAX_ADDR_LEN) /* NDA_LLADDR */
2524                + nla_total_size(sizeof(struct nda_cacheinfo))
2525                + nla_total_size(4); /* NDA_PROBES */
2526 }
2527
2528 static void __neigh_notify(struct neighbour *n, int type, int flags)
2529 {
2530         struct net *net = dev_net(n->dev);
2531         struct sk_buff *skb;
2532         int err = -ENOBUFS;
2533
2534         skb = nlmsg_new(neigh_nlmsg_size(), GFP_ATOMIC);
2535         if (skb == NULL)
2536                 goto errout;
2537
2538         err = neigh_fill_info(skb, n, 0, 0, type, flags);
2539         if (err < 0) {
2540                 /* -EMSGSIZE implies BUG in neigh_nlmsg_size() */
2541                 WARN_ON(err == -EMSGSIZE);
2542                 kfree_skb(skb);
2543                 goto errout;
2544         }
2545         err = rtnl_notify(skb, net, 0, RTNLGRP_NEIGH, NULL, GFP_ATOMIC);
2546 errout:
2547         if (err < 0)
2548                 rtnl_set_sk_err(net, RTNLGRP_NEIGH, err);
2549 }
2550
2551 #ifdef CONFIG_ARPD
2552 void neigh_app_ns(struct neighbour *n)
2553 {
2554         __neigh_notify(n, RTM_GETNEIGH, NLM_F_REQUEST);
2555 }
2556 EXPORT_SYMBOL(neigh_app_ns);
2557 #endif /* CONFIG_ARPD */
2558
2559 #ifdef CONFIG_SYSCTL
2560
2561 static struct neigh_sysctl_table {
2562         struct ctl_table_header *sysctl_header;
2563         struct ctl_table neigh_vars[__NET_NEIGH_MAX];
2564         char *dev_name;
2565 } neigh_sysctl_template __read_mostly = {
2566         .neigh_vars = {
2567                 {
2568                         .ctl_name       = NET_NEIGH_MCAST_SOLICIT,
2569                         .procname       = "mcast_solicit",
2570                         .maxlen         = sizeof(int),
2571                         .mode           = 0644,
2572                         .proc_handler   = &proc_dointvec,
2573                 },
2574                 {
2575                         .ctl_name       = NET_NEIGH_UCAST_SOLICIT,
2576                         .procname       = "ucast_solicit",
2577                         .maxlen         = sizeof(int),
2578                         .mode           = 0644,
2579                         .proc_handler   = &proc_dointvec,
2580                 },
2581                 {
2582                         .ctl_name       = NET_NEIGH_APP_SOLICIT,
2583                         .procname       = "app_solicit",
2584                         .maxlen         = sizeof(int),
2585                         .mode           = 0644,
2586                         .proc_handler   = &proc_dointvec,
2587                 },
2588                 {
2589                         .procname       = "retrans_time",
2590                         .maxlen         = sizeof(int),
2591                         .mode           = 0644,
2592                         .proc_handler   = &proc_dointvec_userhz_jiffies,
2593                 },
2594                 {
2595                         .ctl_name       = NET_NEIGH_REACHABLE_TIME,
2596                         .procname       = "base_reachable_time",
2597                         .maxlen         = sizeof(int),
2598                         .mode           = 0644,
2599                         .proc_handler   = &proc_dointvec_jiffies,
2600                         .strategy       = &sysctl_jiffies,
2601                 },
2602                 {
2603                         .ctl_name       = NET_NEIGH_DELAY_PROBE_TIME,
2604                         .procname       = "delay_first_probe_time",
2605                         .maxlen         = sizeof(int),
2606                         .mode           = 0644,
2607                         .proc_handler   = &proc_dointvec_jiffies,
2608                         .strategy       = &sysctl_jiffies,
2609                 },
2610                 {
2611                         .ctl_name       = NET_NEIGH_GC_STALE_TIME,
2612                         .procname       = "gc_stale_time",
2613                         .maxlen         = sizeof(int),
2614                         .mode           = 0644,
2615                         .proc_handler   = &proc_dointvec_jiffies,
2616                         .strategy       = &sysctl_jiffies,
2617                 },
2618                 {
2619                         .ctl_name       = NET_NEIGH_UNRES_QLEN,
2620                         .procname       = "unres_qlen",
2621                         .maxlen         = sizeof(int),
2622                         .mode           = 0644,
2623                         .proc_handler   = &proc_dointvec,
2624                 },
2625                 {
2626                         .ctl_name       = NET_NEIGH_PROXY_QLEN,
2627                         .procname       = "proxy_qlen",
2628                         .maxlen         = sizeof(int),
2629                         .mode           = 0644,
2630                         .proc_handler   = &proc_dointvec,
2631                 },
2632                 {
2633                         .procname       = "anycast_delay",
2634                         .maxlen         = sizeof(int),
2635                         .mode           = 0644,
2636                         .proc_handler   = &proc_dointvec_userhz_jiffies,
2637                 },
2638                 {
2639                         .procname       = "proxy_delay",
2640                         .maxlen         = sizeof(int),
2641                         .mode           = 0644,
2642                         .proc_handler   = &proc_dointvec_userhz_jiffies,
2643                 },
2644                 {
2645                         .procname       = "locktime",
2646                         .maxlen         = sizeof(int),
2647                         .mode           = 0644,
2648                         .proc_handler   = &proc_dointvec_userhz_jiffies,
2649                 },
2650                 {
2651                         .ctl_name       = NET_NEIGH_RETRANS_TIME_MS,
2652                         .procname       = "retrans_time_ms",
2653                         .maxlen         = sizeof(int),
2654                         .mode           = 0644,
2655                         .proc_handler   = &proc_dointvec_ms_jiffies,
2656                         .strategy       = &sysctl_ms_jiffies,
2657                 },
2658                 {
2659                         .ctl_name       = NET_NEIGH_REACHABLE_TIME_MS,
2660                         .procname       = "base_reachable_time_ms",
2661                         .maxlen         = sizeof(int),
2662                         .mode           = 0644,
2663                         .proc_handler   = &proc_dointvec_ms_jiffies,
2664                         .strategy       = &sysctl_ms_jiffies,
2665                 },
2666                 {
2667                         .ctl_name       = NET_NEIGH_GC_INTERVAL,
2668                         .procname       = "gc_interval",
2669                         .maxlen         = sizeof(int),
2670                         .mode           = 0644,
2671                         .proc_handler   = &proc_dointvec_jiffies,
2672                         .strategy       = &sysctl_jiffies,
2673                 },
2674                 {
2675                         .ctl_name       = NET_NEIGH_GC_THRESH1,
2676                         .procname       = "gc_thresh1",
2677                         .maxlen         = sizeof(int),
2678                         .mode           = 0644,
2679                         .proc_handler   = &proc_dointvec,
2680                 },
2681                 {
2682                         .ctl_name       = NET_NEIGH_GC_THRESH2,
2683                         .procname       = "gc_thresh2",
2684                         .maxlen         = sizeof(int),
2685                         .mode           = 0644,
2686                         .proc_handler   = &proc_dointvec,
2687                 },
2688                 {
2689                         .ctl_name       = NET_NEIGH_GC_THRESH3,
2690                         .procname       = "gc_thresh3",
2691                         .maxlen         = sizeof(int),
2692                         .mode           = 0644,
2693                         .proc_handler   = &proc_dointvec,
2694                 },
2695                 {},
2696         },
2697 };
2698
2699 int neigh_sysctl_register(struct net_device *dev, struct neigh_parms *p,
2700                           int p_id, int pdev_id, char *p_name,
2701                           proc_handler *handler, ctl_handler *strategy)
2702 {
2703         struct neigh_sysctl_table *t;
2704         const char *dev_name_source = NULL;
2705
2706 #define NEIGH_CTL_PATH_ROOT     0
2707 #define NEIGH_CTL_PATH_PROTO    1
2708 #define NEIGH_CTL_PATH_NEIGH    2
2709 #define NEIGH_CTL_PATH_DEV      3
2710
2711         struct ctl_path neigh_path[] = {
2712                 { .procname = "net",     .ctl_name = CTL_NET, },
2713                 { .procname = "proto",   .ctl_name = 0, },
2714                 { .procname = "neigh",   .ctl_name = 0, },
2715                 { .procname = "default", .ctl_name = NET_PROTO_CONF_DEFAULT, },
2716                 { },
2717         };
2718
2719         t = kmemdup(&neigh_sysctl_template, sizeof(*t), GFP_KERNEL);
2720         if (!t)
2721                 goto err;
2722
2723         t->neigh_vars[0].data  = &p->mcast_probes;
2724         t->neigh_vars[1].data  = &p->ucast_probes;
2725         t->neigh_vars[2].data  = &p->app_probes;
2726         t->neigh_vars[3].data  = &p->retrans_time;
2727         t->neigh_vars[4].data  = &p->base_reachable_time;
2728         t->neigh_vars[5].data  = &p->delay_probe_time;
2729         t->neigh_vars[6].data  = &p->gc_staletime;
2730         t->neigh_vars[7].data  = &p->queue_len;
2731         t->neigh_vars[8].data  = &p->proxy_qlen;
2732         t->neigh_vars[9].data  = &p->anycast_delay;
2733         t->neigh_vars[10].data = &p->proxy_delay;
2734         t->neigh_vars[11].data = &p->locktime;
2735         t->neigh_vars[12].data  = &p->retrans_time;
2736         t->neigh_vars[13].data  = &p->base_reachable_time;
2737
2738         if (dev) {
2739                 dev_name_source = dev->name;
2740                 neigh_path[NEIGH_CTL_PATH_DEV].ctl_name = dev->ifindex;
2741                 /* Terminate the table early */
2742                 memset(&t->neigh_vars[14], 0, sizeof(t->neigh_vars[14]));
2743         } else {
2744                 dev_name_source = neigh_path[NEIGH_CTL_PATH_DEV].procname;
2745                 t->neigh_vars[14].data = (int *)(p + 1);
2746                 t->neigh_vars[15].data = (int *)(p + 1) + 1;
2747                 t->neigh_vars[16].data = (int *)(p + 1) + 2;
2748                 t->neigh_vars[17].data = (int *)(p + 1) + 3;
2749         }
2750
2751
2752         if (handler || strategy) {
2753                 /* RetransTime */
2754                 t->neigh_vars[3].proc_handler = handler;
2755                 t->neigh_vars[3].strategy = strategy;
2756                 t->neigh_vars[3].extra1 = dev;
2757                 if (!strategy)
2758                         t->neigh_vars[3].ctl_name = CTL_UNNUMBERED;
2759                 /* ReachableTime */
2760                 t->neigh_vars[4].proc_handler = handler;
2761                 t->neigh_vars[4].strategy = strategy;
2762                 t->neigh_vars[4].extra1 = dev;
2763                 if (!strategy)
2764                         t->neigh_vars[4].ctl_name = CTL_UNNUMBERED;
2765                 /* RetransTime (in milliseconds)*/
2766                 t->neigh_vars[12].proc_handler = handler;
2767                 t->neigh_vars[12].strategy = strategy;
2768                 t->neigh_vars[12].extra1 = dev;
2769                 if (!strategy)
2770                         t->neigh_vars[12].ctl_name = CTL_UNNUMBERED;
2771                 /* ReachableTime (in milliseconds) */
2772                 t->neigh_vars[13].proc_handler = handler;
2773                 t->neigh_vars[13].strategy = strategy;
2774                 t->neigh_vars[13].extra1 = dev;
2775                 if (!strategy)
2776                         t->neigh_vars[13].ctl_name = CTL_UNNUMBERED;
2777         }
2778
2779         t->dev_name = kstrdup(dev_name_source, GFP_KERNEL);
2780         if (!t->dev_name)
2781                 goto free;
2782
2783         neigh_path[NEIGH_CTL_PATH_DEV].procname = t->dev_name;
2784         neigh_path[NEIGH_CTL_PATH_NEIGH].ctl_name = pdev_id;
2785         neigh_path[NEIGH_CTL_PATH_PROTO].procname = p_name;
2786         neigh_path[NEIGH_CTL_PATH_PROTO].ctl_name = p_id;
2787
2788         t->sysctl_header =
2789                 register_net_sysctl_table(neigh_parms_net(p), neigh_path, t->neigh_vars);
2790         if (!t->sysctl_header)
2791                 goto free_procname;
2792
2793         p->sysctl_table = t;
2794         return 0;
2795
2796 free_procname:
2797         kfree(t->dev_name);
2798 free:
2799         kfree(t);
2800 err:
2801         return -ENOBUFS;
2802 }
2803 EXPORT_SYMBOL(neigh_sysctl_register);
2804
2805 void neigh_sysctl_unregister(struct neigh_parms *p)
2806 {
2807         if (p->sysctl_table) {
2808                 struct neigh_sysctl_table *t = p->sysctl_table;
2809                 p->sysctl_table = NULL;
2810                 unregister_sysctl_table(t->sysctl_header);
2811                 kfree(t->dev_name);
2812                 kfree(t);
2813         }
2814 }
2815 EXPORT_SYMBOL(neigh_sysctl_unregister);
2816
2817 #endif  /* CONFIG_SYSCTL */
2818
2819 static int __init neigh_init(void)
2820 {
2821         rtnl_register(PF_UNSPEC, RTM_NEWNEIGH, neigh_add, NULL);
2822         rtnl_register(PF_UNSPEC, RTM_DELNEIGH, neigh_delete, NULL);
2823         rtnl_register(PF_UNSPEC, RTM_GETNEIGH, NULL, neigh_dump_info);
2824
2825         rtnl_register(PF_UNSPEC, RTM_GETNEIGHTBL, NULL, neightbl_dump_info);
2826         rtnl_register(PF_UNSPEC, RTM_SETNEIGHTBL, neightbl_set, NULL);
2827
2828         return 0;
2829 }
2830
2831 subsys_initcall(neigh_init);
2832