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
 127
 128 static int neigh_forced_gc(struct neigh_table *tbl)
 129 {
 130         int shrunk = 0;
 131         int i;
 132
 133         NEIGH_CACHE_STAT_INC(tbl, forced_gc_runs);
 134
 135         write_lock_bh(&tbl->lock);
 136         for (i = 0; i <= tbl->hash_mask; i++) {
 137                 struct neighbour *n, **np;
 138
 139                 np = &tbl->hash_buckets[i];
 140                 while ((n = *np) != NULL) {
 141                         /* Neighbour record may be discarded if:
 142                          * - nobody refers to it.
 143                          * - it is not permanent
 144                          */
 145                         write_lock(&n->lock);
 146                         if (atomic_read(&n->refcnt) == 1 &&
 147                             !(n->nud_state & NUD_PERMANENT)) {
 148                                 *np     = n->next;
 149                                 n->dead = 1;
 150                                 shrunk  = 1;
 151                                 write_unlock(&n->lock);
 152                                 neigh_cleanup_and_release(n);
 153                                 continue;
 154                         }
 155                         write_unlock(&n->lock);
 156                         np = &n->next;
 157                 }
 158         }
 159
 160         tbl->last_flush = jiffies;
 161
 162         write_unlock_bh(&tbl->lock);
 163
 164         return shrunk;
 165 }
 166
 167 static void neigh_add_timer(struct neighbour *n, unsigned long when)
 168 {
 169         neigh_hold(n);
 170         if (unlikely(mod_timer(&n->timer, when))) {
 171                 printk("NEIGH: BUG, double timer add, state is %x\n",
 172                        n->nud_state);
 173                 dump_stack();
 174         }
 175 }
 176
 177 static int neigh_del_timer(struct neighbour *n)
 178 {
 179         if ((n->nud_state & NUD_IN_TIMER) &&
 180             del_timer(&n->timer)) {
 181                 neigh_release(n);
 182                 return 1;
 183         }
 184         return 0;
 185 }
 186
 187 static void pneigh_queue_purge(struct sk_buff_head *list)
 188 {
 189         struct sk_buff *skb;
 190
 191         while ((skb = skb_dequeue(list)) != NULL) {
 192                 dev_put(skb->dev);
 193                 kfree_skb(skb);
 194         }
 195 }
 196
 197 static void neigh_flush_dev(struct neigh_table *tbl, struct net_device *dev)
 198 {
 199         int i;
 200
 201         for (i = 0; i <= tbl->hash_mask; i++) {
 202                 struct neighbour *n, **np = &tbl->hash_buckets[i];
 203
 204                 while ((n = *np) != NULL) {
 205                         if (dev && n->dev != dev) {
 206                                 np = &n->next;
 207                                 continue;
 208                         }
 209                         *np = n->next;
 210                         write_lock(&n->lock);
 211                         neigh_del_timer(n);
 212                         n->dead = 1;
 213
 214                         if (atomic_read(&n->refcnt) != 1) {
 215                                 /* The most unpleasant situation.
 216                                    We must destroy neighbour entry,
 217                                    but someone still uses it.
 218
 219                                    The destroy will be delayed until
 220                                    the last user releases us, but
 221                                    we must kill timers etc. and move
 222                                    it to safe state.
 223                                  */
 224                                 skb_queue_purge(&n->arp_queue);
 225                                 n->output = neigh_blackhole;
 226                                 if (n->nud_state & NUD_VALID)
 227                                         n->nud_state = NUD_NOARP;
 228                                 else
 229                                         n->nud_state = NUD_NONE;
 230                                 NEIGH_PRINTK2("neigh %p is stray.\n", n);
 231                         }
 232                         write_unlock(&n->lock);
 233                         neigh_cleanup_and_release(n);
 234                 }
 235         }
 236 }
 237
 238 void neigh_changeaddr(struct neigh_table *tbl, struct net_device *dev)
 239 {
 240         write_lock_bh(&tbl->lock);
 241         neigh_flush_dev(tbl, dev);
 242         write_unlock_bh(&tbl->lock);
 243 }
 244
 245 int neigh_ifdown(struct neigh_table *tbl, struct net_device *dev)
 246 {
 247         write_lock_bh(&tbl->lock);
 248         neigh_flush_dev(tbl, dev);
 249         pneigh_ifdown(tbl, dev);
 250         write_unlock_bh(&tbl->lock);
 251
 252         del_timer_sync(&tbl->proxy_timer);
 253         pneigh_queue_purge(&tbl->proxy_queue);
 254         return 0;
 255 }
 256
 257 static struct neighbour *neigh_alloc(struct neigh_table *tbl)
 258 {
 259         struct neighbour *n = NULL;
 260         unsigned long now = jiffies;
 261         int entries;
 262
 263         entries = atomic_inc_return(&tbl->entries) - 1;
 264         if (entries >= tbl->gc_thresh3 ||
 265             (entries >= tbl->gc_thresh2 &&
 266              time_after(now, tbl->last_flush + 5 * HZ))) {
 267                 if (!neigh_forced_gc(tbl) &&
 268                     entries >= tbl->gc_thresh3)
 269                         goto out_entries;
 270         }
 271
 272         n = kmem_cache_zalloc(tbl->kmem_cachep, GFP_ATOMIC);
 273         if (!n)
 274                 goto out_entries;
 275
 276         skb_queue_head_init(&n->arp_queue);
 277         rwlock_init(&n->lock);
 278         n->updated        = n->used = now;
 279         n->nud_state      = NUD_NONE;
 280         n->output         = neigh_blackhole;
 281         n->parms          = neigh_parms_clone(&tbl->parms);
 282         setup_timer(&n->timer, neigh_timer_handler, (unsigned long)n);
 283
 284         NEIGH_CACHE_STAT_INC(tbl, allocs);
 285         n->tbl            = tbl;
 286         atomic_set(&n->refcnt, 1);
 287         n->dead           = 1;
 288 out:
 289         return n;
 290
 291 out_entries:
 292         atomic_dec(&tbl->entries);
 293         goto out;
 294 }
 295
 296 static struct neighbour **neigh_hash_alloc(unsigned int entries)
 297 {
 298         unsigned long size = entries * sizeof(struct neighbour *);
 299         struct neighbour **ret;
 300
 301         if (size <= PAGE_SIZE) {
 302                 ret = kzalloc(size, GFP_ATOMIC);
 303         } else {
 304                 ret = (struct neighbour **)
 305                       __get_free_pages(GFP_ATOMIC|__GFP_ZERO, get_order(size));
 306         }
 307         return ret;
 308 }
 309
 310 static void neigh_hash_free(struct neighbour **hash, unsigned int entries)
 311 {
 312         unsigned long size = entries * sizeof(struct neighbour *);
 313
 314         if (size <= PAGE_SIZE)
 315                 kfree(hash);
 316         else
 317                 free_pages((unsigned long)hash, get_order(size));
 318 }
 319
 320 static void neigh_hash_grow(struct neigh_table *tbl, unsigned long new_entries)
 321 {
 322         struct neighbour **new_hash, **old_hash;
 323         unsigned int i, new_hash_mask, old_entries;
 324
 325         NEIGH_CACHE_STAT_INC(tbl, hash_grows);
 326
 327         BUG_ON(!is_power_of_2(new_entries));
 328         new_hash = neigh_hash_alloc(new_entries);
 329         if (!new_hash)
 330                 return;
 331
 332         old_entries = tbl->hash_mask + 1;
 333         new_hash_mask = new_entries - 1;
 334         old_hash = tbl->hash_buckets;
 335
 336         get_random_bytes(&tbl->hash_rnd, sizeof(tbl->hash_rnd));
 337         for (i = 0; i < old_entries; i++) {
 338                 struct neighbour *n, *next;
 339
 340                 for (n = old_hash[i]; n; n = next) {
 341                         unsigned int hash_val = tbl->hash(n->primary_key, n->dev);
 342
 343                         hash_val &= new_hash_mask;
 344                         next = n->next;
 345
 346                         n->next = new_hash[hash_val];
 347                         new_hash[hash_val] = n;
 348                 }
 349         }
 350         tbl->hash_buckets = new_hash;
 351         tbl->hash_mask = new_hash_mask;
 352
 353         neigh_hash_free(old_hash, old_entries);
 354 }
 355
 356 struct neighbour *neigh_lookup(struct neigh_table *tbl, const void *pkey,
 357                                struct net_device *dev)
 358 {
 359         struct neighbour *n;
 360         int key_len = tbl->key_len;
 361         u32 hash_val;
 362
 363         NEIGH_CACHE_STAT_INC(tbl, lookups);
 364
 365         read_lock_bh(&tbl->lock);
 366         hash_val = tbl->hash(pkey, dev);
 367         for (n = tbl->hash_buckets[hash_val & tbl->hash_mask]; n; n = n->next) {
 368                 if (dev == n->dev && !memcmp(n->primary_key, pkey, key_len)) {
 369                         neigh_hold(n);
 370                         NEIGH_CACHE_STAT_INC(tbl, hits);
 371                         break;
 372                 }
 373         }
 374         read_unlock_bh(&tbl->lock);
 375         return n;
 376 }
 377
 378 struct neighbour *neigh_lookup_nodev(struct neigh_table *tbl, struct net *net,
 379                                      const void *pkey)
 380 {
 381         struct neighbour *n;
 382         int key_len = tbl->key_len;
 383         u32 hash_val;
 384
 385         NEIGH_CACHE_STAT_INC(tbl, lookups);
 386
 387         read_lock_bh(&tbl->lock);
 388         hash_val = tbl->hash(pkey, NULL);
 389         for (n = tbl->hash_buckets[hash_val & tbl->hash_mask]; n; n = n->next) {
 390                 if (!memcmp(n->primary_key, pkey, key_len) &&
 391                     net_eq(dev_net(n->dev), net)) {
 392                         neigh_hold(n);
 393                         NEIGH_CACHE_STAT_INC(tbl, hits);
 394                         break;
 395                 }
 396         }
 397         read_unlock_bh(&tbl->lock);
 398         return n;
 399 }
 400
 401 struct neighbour *neigh_create(struct neigh_table *tbl, const void *pkey,
 402                                struct net_device *dev)
 403 {
 404         u32 hash_val;
 405         int key_len = tbl->key_len;
 406         int error;
 407         struct neighbour *n1, *rc, *n = neigh_alloc(tbl);
 408
 409         if (!n) {
 410                 rc = ERR_PTR(-ENOBUFS);
 411                 goto out;
 412         }
 413
 414         memcpy(n->primary_key, pkey, key_len);
 415         n->dev = dev;
 416         dev_hold(dev);
 417
 418         /* Protocol specific setup. */
 419         if (tbl->constructor && (error = tbl->constructor(n)) < 0) {
 420                 rc = ERR_PTR(error);
 421                 goto out_neigh_release;
 422         }
 423
 424         /* Device specific setup. */
 425         if (n->parms->neigh_setup &&
 426             (error = n->parms->neigh_setup(n)) < 0) {
 427                 rc = ERR_PTR(error);
 428                 goto out_neigh_release;
 429         }
 430
 431         n->confirmed = jiffies - (n->parms->base_reachable_time << 1);
 432
 433         write_lock_bh(&tbl->lock);
 434
 435         if (atomic_read(&tbl->entries) > (tbl->hash_mask + 1))
 436                 neigh_hash_grow(tbl, (tbl->hash_mask + 1) << 1);
 437
 438         hash_val = tbl->hash(pkey, dev) & tbl->hash_mask;
 439
 440         if (n->parms->dead) {
 441                 rc = ERR_PTR(-EINVAL);
 442                 goto out_tbl_unlock;
 443         }
 444
 445         for (n1 = tbl->hash_buckets[hash_val]; n1; n1 = n1->next) {
 446                 if (dev == n1->dev && !memcmp(n1->primary_key, pkey, key_len)) {
 447                         neigh_hold(n1);
 448                         rc = n1;
 449                         goto out_tbl_unlock;
 450                 }
 451         }
 452
 453         n->next = tbl->hash_buckets[hash_val];
 454         tbl->hash_buckets[hash_val] = n;
 455         n->dead = 0;
 456         neigh_hold(n);
 457         write_unlock_bh(&tbl->lock);
 458         NEIGH_PRINTK2("neigh %p is created.\n", n);
 459         rc = n;
 460 out:
 461         return rc;
 462 out_tbl_unlock:
 463         write_unlock_bh(&tbl->lock);
 464 out_neigh_release:
 465         neigh_release(n);
 466         goto out;
 467 }
 468
 469 struct pneigh_entry * pneigh_lookup(struct neigh_table *tbl,
 470                                     struct net *net, const void *pkey,
 471                                     struct net_device *dev, int creat)
 472 {
 473         struct pneigh_entry *n;
 474         int key_len = tbl->key_len;
 475         u32 hash_val = *(u32 *)(pkey + key_len - 4);
 476
 477         hash_val ^= (hash_val >> 16);
 478         hash_val ^= hash_val >> 8;
 479         hash_val ^= hash_val >> 4;
 480         hash_val &= PNEIGH_HASHMASK;
 481
 482         read_lock_bh(&tbl->lock);
 483
 484         for (n = tbl->phash_buckets[hash_val]; n; n = n->next) {
 485                 if (!memcmp(n->key, pkey, key_len) &&
 486                     net_eq(pneigh_net(n), net) &&
 487                     (n->dev == dev || !n->dev)) {
 488                         read_unlock_bh(&tbl->lock);
 489                         goto out;
 490                 }
 491         }
 492         read_unlock_bh(&tbl->lock);
 493         n = NULL;
 494         if (!creat)
 495                 goto out;
 496
 497         ASSERT_RTNL();
 498
 499         n = kmalloc(sizeof(*n) + key_len, GFP_KERNEL);
 500         if (!n)
 501                 goto out;
 502
 503 #ifdef CONFIG_NET_NS
 504         n->net = hold_net(net);
 505 #endif
 506         memcpy(n->key, pkey, key_len);
 507         n->dev = dev;
 508         if (dev)
 509                 dev_hold(dev);
 510
 511         if (tbl->pconstructor && tbl->pconstructor(n)) {
 512                 if (dev)
 513                         dev_put(dev);
 514                 release_net(net);
 515                 kfree(n);
 516                 n = NULL;
 517                 goto out;
 518         }
 519
 520         write_lock_bh(&tbl->lock);
 521         n->next = tbl->phash_buckets[hash_val];
 522         tbl->phash_buckets[hash_val] = n;
 523         write_unlock_bh(&tbl->lock);
 524 out:
 525         return n;
 526 }
 527
 528
 529 int pneigh_delete(struct neigh_table *tbl, struct net *net, const void *pkey,
 530                   struct net_device *dev)
 531 {
 532         struct pneigh_entry *n, **np;
 533         int key_len = tbl->key_len;
 534         u32 hash_val = *(u32 *)(pkey + key_len - 4);
 535
 536         hash_val ^= (hash_val >> 16);
 537         hash_val ^= hash_val >> 8;
 538         hash_val ^= hash_val >> 4;
 539         hash_val &= PNEIGH_HASHMASK;
 540
 541         write_lock_bh(&tbl->lock);
 542         for (np = &tbl->phash_buckets[hash_val]; (n = *np) != NULL;
 543              np = &n->next) {
 544                 if (!memcmp(n->key, pkey, key_len) && n->dev == dev &&
 545                     net_eq(pneigh_net(n), net)) {
 546                         *np = n->next;
 547                         write_unlock_bh(&tbl->lock);
 548                         if (tbl->pdestructor)
 549                                 tbl->pdestructor(n);
 550                         if (n->dev)
 551                                 dev_put(n->dev);
 552                         release_net(pneigh_net(n));
 553                         kfree(n);
 554                         return 0;
 555                 }
 556         }
 557         write_unlock_bh(&tbl->lock);
 558         return -ENOENT;
 559 }
 560
 561 static int pneigh_ifdown(struct neigh_table *tbl, struct net_device *dev)
 562 {
 563         struct pneigh_entry *n, **np;
 564         u32 h;
 565
 566         for (h = 0; h <= PNEIGH_HASHMASK; h++) {
 567                 np = &tbl->phash_buckets[h];
 568                 while ((n = *np) != NULL) {
 569                         if (!dev || n->dev == dev) {
 570                                 *np = n->next;
 571                                 if (tbl->pdestructor)
 572                                         tbl->pdestructor(n);
 573                                 if (n->dev)
 574                                         dev_put(n->dev);
 575                                 release_net(pneigh_net(n));
 576                                 kfree(n);
 577                                 continue;
 578                         }
 579                         np = &n->next;
 580                 }
 581         }
 582         return -ENOENT;
 583 }
 584
 585 static void neigh_parms_destroy(struct neigh_parms *parms);
 586
 587 static inline void neigh_parms_put(struct neigh_parms *parms)
 588 {
 589         if (atomic_dec_and_test(&parms->refcnt))
 590                 neigh_parms_destroy(parms);
 591 }
 592
 593 /*
 594  *      neighbour must already be out of the table;
 595  *
 596  */
 597 void neigh_destroy(struct neighbour *neigh)
 598 {
 599         struct hh_cache *hh;
 600
 601         NEIGH_CACHE_STAT_INC(neigh->tbl, destroys);
 602
 603         if (!neigh->dead) {
 604                 printk(KERN_WARNING
 605                        "Destroying alive neighbour %p\n", neigh);
 606                 dump_stack();
 607                 return;
 608         }
 609
 610         if (neigh_del_timer(neigh))
 611                 printk(KERN_WARNING "Impossible event.\n");
 612
 613         while ((hh = neigh->hh) != NULL) {
 614                 neigh->hh = hh->hh_next;
 615                 hh->hh_next = NULL;
 616
 617                 write_seqlock_bh(&hh->hh_lock);
 618                 hh->hh_output = neigh_blackhole;
 619                 write_sequnlock_bh(&hh->hh_lock);
 620                 if (atomic_dec_and_test(&hh->hh_refcnt))
 621                         kfree(hh);
 622         }
 623
 624         skb_queue_purge(&neigh->arp_queue);
 625
 626         dev_put(neigh->dev);
 627         neigh_parms_put(neigh->parms);
 628
 629         NEIGH_PRINTK2("neigh %p is destroyed.\n", neigh);
 630
 631         atomic_dec(&neigh->tbl->entries);
 632         kmem_cache_free(neigh->tbl->kmem_cachep, neigh);
 633 }
 634
 635 /* Neighbour state is suspicious;
 636    disable fast path.
 637
 638    Called with write_locked neigh.
 639  */
 640 static void neigh_suspect(struct neighbour *neigh)
 641 {
 642         struct hh_cache *hh;
 643
 644         NEIGH_PRINTK2("neigh %p is suspected.\n", neigh);
 645
 646         neigh->output = neigh->ops->output;
 647
 648         for (hh = neigh->hh; hh; hh = hh->hh_next)
 649                 hh->hh_output = neigh->ops->output;
 650 }
 651
 652 /* Neighbour state is OK;
 653    enable fast path.
 654
 655    Called with write_locked neigh.
 656  */
 657 static void neigh_connect(struct neighbour *neigh)
 658 {
 659         struct hh_cache *hh;
 660
 661         NEIGH_PRINTK2("neigh %p is connected.\n", neigh);
 662
 663         neigh->output = neigh->ops->connected_output;
 664
 665         for (hh = neigh->hh; hh; hh = hh->hh_next)
 666                 hh->hh_output = neigh->ops->hh_output;
 667 }
 668
 669 static void neigh_periodic_timer(unsigned long arg)
 670 {
 671         struct neigh_table *tbl = (struct neigh_table *)arg;
 672         struct neighbour *n, **np;
 673         unsigned long expire, now = jiffies;
 674
 675         NEIGH_CACHE_STAT_INC(tbl, periodic_gc_runs);
 676
 677         write_lock(&tbl->lock);
 678
 679         /*
 680          *      periodically recompute ReachableTime from random function
 681          */
 682
 683         if (time_after(now, tbl->last_rand + 300 * HZ)) {
 684                 struct neigh_parms *p;
 685                 tbl->last_rand = now;
 686                 for (p = &tbl->parms; p; p = p->next)
 687                         p->reachable_time =
 688                                 neigh_rand_reach_time(p->base_reachable_time);
 689         }
 690
 691         np = &tbl->hash_buckets[tbl->hash_chain_gc];
 692         tbl->hash_chain_gc = ((tbl->hash_chain_gc + 1) & tbl->hash_mask);
 693
 694         while ((n = *np) != NULL) {
 695                 unsigned int state;
 696
 697                 write_lock(&n->lock);
 698
 699                 state = n->nud_state;
 700                 if (state & (NUD_PERMANENT | NUD_IN_TIMER)) {
 701                         write_unlock(&n->lock);
 702                         goto next_elt;
 703                 }
 704
 705                 if (time_before(n->used, n->confirmed))
 706                         n->used = n->confirmed;
 707
 708                 if (atomic_read(&n->refcnt) == 1 &&
 709                     (state == NUD_FAILED ||
 710                      time_after(now, n->used + n->parms->gc_staletime))) {
 711                         *np = n->next;
 712                         n->dead = 1;
 713                         write_unlock(&n->lock);
 714                         neigh_cleanup_and_release(n);
 715                         continue;
 716                 }
 717                 write_unlock(&n->lock);
 718
 719 next_elt:
 720                 np = &n->next;
 721         }
 722
 723         /* Cycle through all hash buckets every base_reachable_time/2 ticks.
 724          * ARP entry timeouts range from 1/2 base_reachable_time to 3/2
 725          * base_reachable_time.
 726          */
 727         expire = tbl->parms.base_reachable_time >> 1;
 728         expire /= (tbl->hash_mask + 1);
 729         if (!expire)
 730                 expire = 1;
 731
 732         if (expire>HZ)
 733                 mod_timer(&tbl->gc_timer, round_jiffies(now + expire));
 734         else
 735                 mod_timer(&tbl->gc_timer, now + expire);
 736
 737         write_unlock(&tbl->lock);
 738 }
 739
 740 static __inline__ int neigh_max_probes(struct neighbour *n)
 741 {
 742         struct neigh_parms *p = n->parms;
 743         return (n->nud_state & NUD_PROBE ?
 744                 p->ucast_probes :
 745                 p->ucast_probes + p->app_probes + p->mcast_probes);
 746 }
 747
 748 /* Called when a timer expires for a neighbour entry. */
 749
 750 static void neigh_timer_handler(unsigned long arg)
 751 {
 752         unsigned long now, next;
 753         struct neighbour *neigh = (struct neighbour *)arg;
 754         unsigned state;
 755         int notify = 0;
 756
 757         write_lock(&neigh->lock);
 758
 759         state = neigh->nud_state;
 760         now = jiffies;
 761         next = now + HZ;
 762
 763         if (!(state & NUD_IN_TIMER)) {
 764 #ifndef CONFIG_SMP
 765                 printk(KERN_WARNING "neigh: timer & !nud_in_timer\n");
 766 #endif
 767                 goto out;
 768         }
 769
 770         if (state & NUD_REACHABLE) {
 771                 if (time_before_eq(now,
 772                                    neigh->confirmed + neigh->parms->reachable_time)) {
 773                         NEIGH_PRINTK2("neigh %p is still alive.\n", neigh);
 774                         next = neigh->confirmed + neigh->parms->reachable_time;
 775                 } else if (time_before_eq(now,
 776                                           neigh->used + neigh->parms->delay_probe_time)) {
 777                         NEIGH_PRINTK2("neigh %p is delayed.\n", neigh);
 778                         neigh->nud_state = NUD_DELAY;
 779                         neigh->updated = jiffies;
 780                         neigh_suspect(neigh);
 781                         next = now + neigh->parms->delay_probe_time;
 782                 } else {
 783                         NEIGH_PRINTK2("neigh %p is suspected.\n", neigh);
 784                         neigh->nud_state = NUD_STALE;
 785                         neigh->updated = jiffies;
 786                         neigh_suspect(neigh);
 787                         notify = 1;
 788                 }
 789         } else if (state & NUD_DELAY) {
 790                 if (time_before_eq(now,
 791                                    neigh->confirmed + neigh->parms->delay_probe_time)) {
 792                         NEIGH_PRINTK2("neigh %p is now reachable.\n", neigh);
 793                         neigh->nud_state = NUD_REACHABLE;
 794                         neigh->updated = jiffies;
 795                         neigh_connect(neigh);
 796                         notify = 1;
 797                         next = neigh->confirmed + neigh->parms->reachable_time;
 798                 } else {
 799                         NEIGH_PRINTK2("neigh %p is probed.\n", neigh);
 800                         neigh->nud_state = NUD_PROBE;
 801                         neigh->updated = jiffies;
 802                         atomic_set(&neigh->probes, 0);
 803                         next = now + neigh->parms->retrans_time;
 804                 }
 805         } else {
 806                 /* NUD_PROBE|NUD_INCOMPLETE */
 807                 next = now + neigh->parms->retrans_time;
 808         }
 809
 810         if ((neigh->nud_state & (NUD_INCOMPLETE | NUD_PROBE)) &&
 811             atomic_read(&neigh->probes) >= neigh_max_probes(neigh)) {
 812                 struct sk_buff *skb;
 813
 814                 neigh->nud_state = NUD_FAILED;
 815                 neigh->updated = jiffies;
 816                 notify = 1;
 817                 NEIGH_CACHE_STAT_INC(neigh->tbl, res_failed);
 818                 NEIGH_PRINTK2("neigh %p is failed.\n", neigh);
 819
 820                 /* It is very thin place. report_unreachable is very complicated
 821                    routine. Particularly, it can hit the same neighbour entry!
 822
 823                    So that, we try to be accurate and avoid dead loop. --ANK
 824                  */
 825                 while (neigh->nud_state == NUD_FAILED &&
 826                        (skb = __skb_dequeue(&neigh->arp_queue)) != NULL) {
 827                         write_unlock(&neigh->lock);
 828                         neigh->ops->error_report(neigh, skb);
 829                         write_lock(&neigh->lock);
 830                 }
 831                 skb_queue_purge(&neigh->arp_queue);
 832         }
 833
 834         if (neigh->nud_state & NUD_IN_TIMER) {
 835                 if (time_before(next, jiffies + HZ/2))
 836                         next = jiffies + HZ/2;
 837                 if (!mod_timer(&neigh->timer, next))
 838                         neigh_hold(neigh);
 839         }
 840         if (neigh->nud_state & (NUD_INCOMPLETE | NUD_PROBE)) {
 841                 struct sk_buff *skb = skb_peek(&neigh->arp_queue);
 842                 /* keep skb alive even if arp_queue overflows */
 843                 if (skb)
 844                         skb = skb_copy(skb, GFP_ATOMIC);
 845                 write_unlock(&neigh->lock);
 846                 neigh->ops->solicit(neigh, skb);
 847                 atomic_inc(&neigh->probes);
 848                 if (skb)
 849                         kfree_skb(skb);
 850         } else {
 851 out:
 852                 write_unlock(&neigh->lock);
 853         }
 854
 855         if (notify)
 856                 neigh_update_notify(neigh);
 857
 858         neigh_release(neigh);
 859 }
 860
 861 int __neigh_event_send(struct neighbour *neigh, struct sk_buff *skb)
 862 {
 863         int rc;
 864         unsigned long now;
 865
 866         write_lock_bh(&neigh->lock);
 867
 868         rc = 0;
 869         if (neigh->nud_state & (NUD_CONNECTED | NUD_DELAY | NUD_PROBE))
 870                 goto out_unlock_bh;
 871
 872         now = jiffies;
 873
 874         if (!(neigh->nud_state & (NUD_STALE | NUD_INCOMPLETE))) {
 875                 if (neigh->parms->mcast_probes + neigh->parms->app_probes) {
 876                         atomic_set(&neigh->probes, neigh->parms->ucast_probes);
 877                         neigh->nud_state     = NUD_INCOMPLETE;
 878                         neigh->updated = jiffies;
 879                         neigh_add_timer(neigh, now + 1);
 880                 } else {
 881                         neigh->nud_state = NUD_FAILED;
 882                         neigh->updated = jiffies;
 883                         write_unlock_bh(&neigh->lock);
 884
 885                         if (skb)
 886                                 kfree_skb(skb);
 887                         return 1;
 888                 }
 889         } else if (neigh->nud_state & NUD_STALE) {
 890                 NEIGH_PRINTK2("neigh %p is delayed.\n", neigh);
 891                 neigh->nud_state = NUD_DELAY;
 892                 neigh->updated = jiffies;
 893                 neigh_add_timer(neigh,
 894                                 jiffies + neigh->parms->delay_probe_time);
 895         }
 896
 897         if (neigh->nud_state == NUD_INCOMPLETE) {
 898                 if (skb) {
 899                         if (skb_queue_len(&neigh->arp_queue) >=
 900                             neigh->parms->queue_len) {
 901                                 struct sk_buff *buff;
 902                                 buff = neigh->arp_queue.next;
 903                                 __skb_unlink(buff, &neigh->arp_queue);
 904                                 kfree_skb(buff);
 905                         }
 906                         __skb_queue_tail(&neigh->arp_queue, skb);
 907                 }
 908                 rc = 1;
 909         }
 910 out_unlock_bh:
 911         write_unlock_bh(&neigh->lock);
 912         return rc;
 913 }
 914
 915 static void neigh_update_hhs(struct neighbour *neigh)
 916 {
 917         struct hh_cache *hh;
 918         void (*update)(struct hh_cache*, const struct net_device*, const unsigned char *)
 919                 = neigh->dev->header_ops->cache_update;
 920
 921         if (update) {
 922                 for (hh = neigh->hh; hh; hh = hh->hh_next) {
 923                         write_seqlock_bh(&hh->hh_lock);
 924                         update(hh, neigh->dev, neigh->ha);
 925                         write_sequnlock_bh(&hh->hh_lock);
 926                 }
 927         }
 928 }
 929
 930
 931
 932 /* Generic update routine.
 933    -- lladdr is new lladdr or NULL, if it is not supplied.
 934    -- new    is new state.
 935    -- flags
 936         NEIGH_UPDATE_F_OVERRIDE allows to override existing lladdr,
 937                                 if it is different.
 938         NEIGH_UPDATE_F_WEAK_OVERRIDE will suspect existing "connected"
 939                                 lladdr instead of overriding it
 940                                 if it is different.
 941                                 It also allows to retain current state
 942                                 if lladdr is unchanged.
 943         NEIGH_UPDATE_F_ADMIN    means that the change is administrative.
 944
 945         NEIGH_UPDATE_F_OVERRIDE_ISROUTER allows to override existing
 946                                 NTF_ROUTER flag.
 947         NEIGH_UPDATE_F_ISROUTER indicates if the neighbour is known as
 948                                 a router.
 949
 950    Caller MUST hold reference count on the entry.
 951  */
 952
 953 int neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new,
 954                  u32 flags)
 955 {
 956         u8 old;
 957         int err;
 958         int notify = 0;
 959         struct net_device *dev;
 960         int update_isrouter = 0;
 961
 962         write_lock_bh(&neigh->lock);
 963
 964         dev    = neigh->dev;
 965         old    = neigh->nud_state;
 966         err    = -EPERM;
 967
 968         if (!(flags & NEIGH_UPDATE_F_ADMIN) &&
 969             (old & (NUD_NOARP | NUD_PERMANENT)))
 970                 goto out;
 971
 972         if (!(new & NUD_VALID)) {
 973                 neigh_del_timer(neigh);
 974                 if (old & NUD_CONNECTED)
 975                         neigh_suspect(neigh);
 976                 neigh->nud_state = new;
 977                 err = 0;
 978                 notify = old & NUD_VALID;
 979                 goto out;
 980         }
 981
 982         /* Compare new lladdr with cached one */
 983         if (!dev->addr_len) {
 984                 /* First case: device needs no address. */
 985                 lladdr = neigh->ha;
 986         } else if (lladdr) {
 987                 /* The second case: if something is already cached
 988                    and a new address is proposed:
 989                    - compare new & old
 990                    - if they are different, check override flag
 991                  */
 992                 if ((old & NUD_VALID) &&
 993                     !memcmp(lladdr, neigh->ha, dev->addr_len))
 994                         lladdr = neigh->ha;
 995         } else {
 996                 /* No address is supplied; if we know something,
 997                    use it, otherwise discard the request.
 998                  */
 999                 err = -EINVAL;
1000                 if (!(old & NUD_VALID))
1001                         goto out;
1002                 lladdr = neigh->ha;
1003         }
1004
1005         if (new & NUD_CONNECTED)
1006                 neigh->confirmed = jiffies;
1007         neigh->updated = jiffies;
1008
1009         /* If entry was valid and address is not changed,
1010            do not change entry state, if new one is STALE.
1011          */
1012         err = 0;
1013         update_isrouter = flags & NEIGH_UPDATE_F_OVERRIDE_ISROUTER;
1014         if (old & NUD_VALID) {
1015                 if (lladdr != neigh->ha && !(flags & NEIGH_UPDATE_F_OVERRIDE)) {
1016                         update_isrouter = 0;
1017                         if ((flags & NEIGH_UPDATE_F_WEAK_OVERRIDE) &&
1018                             (old & NUD_CONNECTED)) {
1019                                 lladdr = neigh->ha;
1020                                 new = NUD_STALE;
1021                         } else
1022                                 goto out;
1023                 } else {
1024                         if (lladdr == neigh->ha && new == NUD_STALE &&
1025                             ((flags & NEIGH_UPDATE_F_WEAK_OVERRIDE) ||
1026                              (old & NUD_CONNECTED))
1027                             )
1028                                 new = old;
1029                 }
1030         }
1031
1032         if (new != old) {
1033                 neigh_del_timer(neigh);
1034                 if (new & NUD_IN_TIMER)
1035                         neigh_add_timer(neigh, (jiffies +
1036                                                 ((new & NUD_REACHABLE) ?
1037                                                  neigh->parms->reachable_time :
1038                                                  0)));
1039                 neigh->nud_state = new;
1040         }
1041
1042         if (lladdr != neigh->ha) {
1043                 memcpy(&neigh->ha, lladdr, dev->addr_len);
1044                 neigh_update_hhs(neigh);
1045                 if (!(new & NUD_CONNECTED))
1046                         neigh->confirmed = jiffies -
1047                                       (neigh->parms->base_reachable_time << 1);
1048                 notify = 1;
1049         }
1050         if (new == old)
1051                 goto out;
1052         if (new & NUD_CONNECTED)
1053                 neigh_connect(neigh);
1054         else
1055                 neigh_suspect(neigh);
1056         if (!(old & NUD_VALID)) {
1057                 struct sk_buff *skb;
1058
1059                 /* Again: avoid dead loop if something went wrong */
1060
1061                 while (neigh->nud_state & NUD_VALID &&
1062                        (skb = __skb_dequeue(&neigh->arp_queue)) != NULL) {
1063                         struct neighbour *n1 = neigh;
1064                         write_unlock_bh(&neigh->lock);
1065                         /* On shaper/eql skb->dst->neighbour != neigh :( */
1066                         if (skb->dst && skb->dst->neighbour)
1067                                 n1 = skb->dst->neighbour;
1068                         n1->output(skb);
1069                         write_lock_bh(&neigh->lock);
1070                 }
1071                 skb_queue_purge(&neigh->arp_queue);
1072         }
1073 out:
1074         if (update_isrouter) {
1075                 neigh->flags = (flags & NEIGH_UPDATE_F_ISROUTER) ?
1076                         (neigh->flags | NTF_ROUTER) :
1077                         (neigh->flags & ~NTF_ROUTER);
1078         }
1079         write_unlock_bh(&neigh->lock);
1080
1081         if (notify)
1082                 neigh_update_notify(neigh);
1083
1084         return err;
1085 }
1086
1087 struct neighbour *neigh_event_ns(struct neigh_table *tbl,
1088                                  u8 *lladdr, void *saddr,
1089                                  struct net_device *dev)
1090 {
1091         struct neighbour *neigh = __neigh_lookup(tbl, saddr, dev,
1092                                                  lladdr || !dev->addr_len);
1093         if (neigh)
1094                 neigh_update(neigh, lladdr, NUD_STALE,
1095                              NEIGH_UPDATE_F_OVERRIDE);
1096         return neigh;
1097 }
1098
1099 static void neigh_hh_init(struct neighbour *n, struct dst_entry *dst,
1100                           __be16 protocol)
1101 {
1102         struct hh_cache *hh;
1103         struct net_device *dev = dst->dev;
1104
1105         for (hh = n->hh; hh; hh = hh->hh_next)
1106                 if (hh->hh_type == protocol)
1107                         break;
1108
1109         if (!hh && (hh = kzalloc(sizeof(*hh), GFP_ATOMIC)) != NULL) {
1110                 seqlock_init(&hh->hh_lock);
1111                 hh->hh_type = protocol;
1112                 atomic_set(&hh->hh_refcnt, 0);
1113                 hh->hh_next = NULL;
1114
1115                 if (dev->header_ops->cache(n, hh)) {
1116                         kfree(hh);
1117                         hh = NULL;
1118                 } else {
1119                         atomic_inc(&hh->hh_refcnt);
1120                         hh->hh_next = n->hh;
1121                         n->hh       = hh;
1122                         if (n->nud_state & NUD_CONNECTED)
1123                                 hh->hh_output = n->ops->hh_output;
1124                         else
1125                                 hh->hh_output = n->ops->output;
1126                 }
1127         }
1128         if (hh) {
1129                 atomic_inc(&hh->hh_refcnt);
1130                 dst->hh = hh;
1131         }
1132 }
1133
1134 /* This function can be used in contexts, where only old dev_queue_xmit
1135    worked, f.e. if you want to override normal output path (eql, shaper),
1136    but resolution is not made yet.
1137  */
1138
1139 int neigh_compat_output(struct sk_buff *skb)
1140 {
1141         struct net_device *dev = skb->dev;
1142
1143         __skb_pull(skb, skb_network_offset(skb));
1144
1145         if (dev_hard_header(skb, dev, ntohs(skb->protocol), NULL, NULL,
1146                             skb->len) < 0 &&
1147             dev->header_ops->rebuild(skb))
1148                 return 0;
1149
1150         return dev_queue_xmit(skb);
1151 }
1152
1153 /* Slow and careful. */
1154
1155 int neigh_resolve_output(struct sk_buff *skb)
1156 {
1157         struct dst_entry *dst = skb->dst;
1158         struct neighbour *neigh;
1159         int rc = 0;
1160
1161         if (!dst || !(neigh = dst->neighbour))
1162                 goto discard;
1163
1164         __skb_pull(skb, skb_network_offset(skb));
1165
1166         if (!neigh_event_send(neigh, skb)) {
1167                 int err;
1168                 struct net_device *dev = neigh->dev;
1169                 if (dev->header_ops->cache && !dst->hh) {
1170                         write_lock_bh(&neigh->lock);
1171                         if (!dst->hh)
1172                                 neigh_hh_init(neigh, dst, dst->ops->protocol);
1173                         err = dev_hard_header(skb, dev, ntohs(skb->protocol),
1174                                               neigh->ha, NULL, skb->len);
1175                         write_unlock_bh(&neigh->lock);
1176                 } else {
1177                         read_lock_bh(&neigh->lock);
1178                         err = dev_hard_header(skb, dev, ntohs(skb->protocol),
1179                                               neigh->ha, NULL, skb->len);
1180                         read_unlock_bh(&neigh->lock);
1181                 }
1182                 if (err >= 0)
1183                         rc = neigh->ops->queue_xmit(skb);
1184                 else
1185                         goto out_kfree_skb;
1186         }
1187 out:
1188         return rc;
1189 discard:
1190         NEIGH_PRINTK1("neigh_resolve_output: dst=%p neigh=%p\n",
1191                       dst, dst ? dst->neighbour : NULL);
1192 out_kfree_skb:
1193         rc = -EINVAL;
1194         kfree_skb(skb);
1195         goto out;
1196 }
1197
1198 /* As fast as possible without hh cache */
1199
1200 int neigh_connected_output(struct sk_buff *skb)
1201 {
1202         int err;
1203         struct dst_entry *dst = skb->dst;
1204         struct neighbour *neigh = dst->neighbour;
1205         struct net_device *dev = neigh->dev;
1206
1207         __skb_pull(skb, skb_network_offset(skb));
1208
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         if (err >= 0)
1214                 err = neigh->ops->queue_xmit(skb);
1215         else {
1216                 err = -EINVAL;
1217                 kfree_skb(skb);
1218         }
1219         return err;
1220 }
1221
1222 static void neigh_proxy_process(unsigned long arg)
1223 {
1224         struct neigh_table *tbl = (struct neigh_table *)arg;
1225         long sched_next = 0;
1226         unsigned long now = jiffies;
1227         struct sk_buff *skb;
1228
1229         spin_lock(&tbl->proxy_queue.lock);
1230
1231         skb = tbl->proxy_queue.next;
1232
1233         while (skb != (struct sk_buff *)&tbl->proxy_queue) {
1234                 struct sk_buff *back = skb;
1235                 long tdif = NEIGH_CB(back)->sched_next - now;
1236
1237                 skb = skb->next;
1238                 if (tdif <= 0) {
1239                         struct net_device *dev = back->dev;
1240                         __skb_unlink(back, &tbl->proxy_queue);
1241                         if (tbl->proxy_redo && netif_running(dev))
1242                                 tbl->proxy_redo(back);
1243                         else
1244                                 kfree_skb(back);
1245
1246                         dev_put(dev);
1247                 } else if (!sched_next || tdif < sched_next)
1248                         sched_next = tdif;
1249         }
1250         del_timer(&tbl->proxy_timer);
1251         if (sched_next)
1252                 mod_timer(&tbl->proxy_timer, jiffies + sched_next);
1253         spin_unlock(&tbl->proxy_queue.lock);
1254 }
1255
1256 void pneigh_enqueue(struct neigh_table *tbl, struct neigh_parms *p,
1257                     struct sk_buff *skb)
1258 {
1259         unsigned long now = jiffies;
1260         unsigned long sched_next = now + (net_random() % p->proxy_delay);
1261
1262         if (tbl->proxy_queue.qlen > p->proxy_qlen) {
1263                 kfree_skb(skb);
1264                 return;
1265         }
1266
1267         NEIGH_CB(skb)->sched_next = sched_next;
1268         NEIGH_CB(skb)->flags |= LOCALLY_ENQUEUED;
1269
1270         spin_lock(&tbl->proxy_queue.lock);
1271         if (del_timer(&tbl->proxy_timer)) {
1272                 if (time_before(tbl->proxy_timer.expires, sched_next))
1273                         sched_next = tbl->proxy_timer.expires;
1274         }
1275         dst_release(skb->dst);
1276         skb->dst = NULL;
1277         dev_hold(skb->dev);
1278         __skb_queue_tail(&tbl->proxy_queue, skb);
1279         mod_timer(&tbl->proxy_timer, sched_next);
1280         spin_unlock(&tbl->proxy_queue.lock);
1281 }
1282
1283 static inline struct neigh_parms *lookup_neigh_params(struct neigh_table *tbl,
1284                                                       struct net *net, int ifindex)
1285 {
1286         struct neigh_parms *p;
1287
1288         for (p = &tbl->parms; p; p = p->next) {
1289                 if ((p->dev && p->dev->ifindex == ifindex && net_eq(neigh_parms_net(p), net)) ||
1290                     (!p->dev && !ifindex))
1291                         return p;
1292         }
1293
1294         return NULL;
1295 }
1296
1297 struct neigh_parms *neigh_parms_alloc(struct net_device *dev,
1298                                       struct neigh_table *tbl)
1299 {
1300         struct neigh_parms *p, *ref;
1301         struct net *net;
1302
1303         net = dev_net(dev);
1304         ref = lookup_neigh_params(tbl, net, 0);
1305         if (!ref)
1306                 return NULL;
1307
1308         p = kmemdup(ref, sizeof(*p), GFP_KERNEL);
1309         if (p) {
1310                 p->tbl            = tbl;
1311                 atomic_set(&p->refcnt, 1);
1312                 INIT_RCU_HEAD(&p->rcu_head);
1313                 p->reachable_time =
1314                                 neigh_rand_reach_time(p->base_reachable_time);
1315
1316                 if (dev->neigh_setup && dev->neigh_setup(dev, p)) {
1317                         kfree(p);
1318                         return NULL;
1319                 }
1320
1321                 dev_hold(dev);
1322                 p->dev = dev;
1323 #ifdef CONFIG_NET_NS
1324                 p->net = hold_net(net);
1325 #endif
1326                 p->sysctl_table = NULL;
1327                 write_lock_bh(&tbl->lock);
1328                 p->next         = tbl->parms.next;
1329                 tbl->parms.next = p;
1330                 write_unlock_bh(&tbl->lock);
1331         }
1332         return p;
1333 }
1334
1335 static void neigh_rcu_free_parms(struct rcu_head *head)
1336 {
1337         struct neigh_parms *parms =
1338                 container_of(head, struct neigh_parms, rcu_head);
1339
1340         neigh_parms_put(parms);
1341 }
1342
1343 void neigh_parms_release(struct neigh_table *tbl, struct neigh_parms *parms)
1344 {
1345         struct neigh_parms **p;
1346
1347         if (!parms || parms == &tbl->parms)
1348                 return;
1349         write_lock_bh(&tbl->lock);
1350         for (p = &tbl->parms.next; *p; p = &(*p)->next) {
1351                 if (*p == parms) {
1352                         *p = parms->next;
1353                         parms->dead = 1;
1354                         write_unlock_bh(&tbl->lock);
1355                         if (parms->dev)
1356                                 dev_put(parms->dev);
1357                         call_rcu(&parms->rcu_head, neigh_rcu_free_parms);
1358                         return;
1359                 }
1360         }
1361         write_unlock_bh(&tbl->lock);
1362         NEIGH_PRINTK1("neigh_parms_release: not found\n");
1363 }
1364
1365 static void neigh_parms_destroy(struct neigh_parms *parms)
1366 {
1367         release_net(neigh_parms_net(parms));
1368         kfree(parms);
1369 }
1370
1371 static struct lock_class_key neigh_table_proxy_queue_class;
1372
1373 void neigh_table_init_no_netlink(struct neigh_table *tbl)
1374 {
1375         unsigned long now = jiffies;
1376         unsigned long phsize;
1377
1378 #ifdef CONFIG_NET_NS
1379         tbl->parms.net = &init_net;
1380 #endif
1381         atomic_set(&tbl->parms.refcnt, 1);
1382         INIT_RCU_HEAD(&tbl->parms.rcu_head);
1383         tbl->parms.reachable_time =
1384                           neigh_rand_reach_time(tbl->parms.base_reachable_time);
1385
1386         if (!tbl->kmem_cachep)
1387                 tbl->kmem_cachep =
1388                         kmem_cache_create(tbl->id, tbl->entry_size, 0,
1389                                           SLAB_HWCACHE_ALIGN|SLAB_PANIC,
1390                                           NULL);
1391         tbl->stats = alloc_percpu(struct neigh_statistics);
1392         if (!tbl->stats)
1393                 panic("cannot create neighbour cache statistics");
1394
1395 #ifdef CONFIG_PROC_FS
1396         tbl->pde = proc_create(tbl->id, 0, init_net.proc_net_stat,
1397                                &neigh_stat_seq_fops);
1398         if (!tbl->pde)
1399                 panic("cannot create neighbour proc dir entry");
1400         tbl->pde->data = tbl;
1401 #endif
1402
1403         tbl->hash_mask = 1;
1404         tbl->hash_buckets = neigh_hash_alloc(tbl->hash_mask + 1);
1405
1406         phsize = (PNEIGH_HASHMASK + 1) * sizeof(struct pneigh_entry *);
1407         tbl->phash_buckets = kzalloc(phsize, GFP_KERNEL);
1408
1409         if (!tbl->hash_buckets || !tbl->phash_buckets)
1410                 panic("cannot allocate neighbour cache hashes");
1411
1412         get_random_bytes(&tbl->hash_rnd, sizeof(tbl->hash_rnd));
1413
1414         rwlock_init(&tbl->lock);
1415         setup_timer(&tbl->gc_timer, neigh_periodic_timer, (unsigned long)tbl);
1416         tbl->gc_timer.expires  = now + 1;
1417         add_timer(&tbl->gc_timer);
1418
1419         setup_timer(&tbl->proxy_timer, neigh_proxy_process, (unsigned long)tbl);
1420         skb_queue_head_init_class(&tbl->proxy_queue,
1421                         &neigh_table_proxy_queue_class);
1422
1423         tbl->last_flush = now;
1424         tbl->last_rand  = now + tbl->parms.reachable_time * 20;
1425 }
1426
1427 void neigh_table_init(struct neigh_table *tbl)
1428 {
1429         struct neigh_table *tmp;
1430
1431         neigh_table_init_no_netlink(tbl);
1432         write_lock(&neigh_tbl_lock);
1433         for (tmp = neigh_tables; tmp; tmp = tmp->next) {
1434                 if (tmp->family == tbl->family)
1435                         break;
1436         }
1437         tbl->next       = neigh_tables;
1438         neigh_tables    = tbl;
1439         write_unlock(&neigh_tbl_lock);
1440
1441         if (unlikely(tmp)) {
1442                 printk(KERN_ERR "NEIGH: Registering multiple tables for "
1443                        "family %d\n", tbl->family);
1444                 dump_stack();
1445         }
1446 }
1447
1448 int neigh_table_clear(struct neigh_table *tbl)
1449 {
1450         struct neigh_table **tp;
1451
1452         /* It is not clean... Fix it to unload IPv6 module safely */
1453         del_timer_sync(&tbl->gc_timer);
1454         del_timer_sync(&tbl->proxy_timer);
1455         pneigh_queue_purge(&tbl->proxy_queue);
1456         neigh_ifdown(tbl, NULL);
1457         if (atomic_read(&tbl->entries))
1458                 printk(KERN_CRIT "neighbour leakage\n");
1459         write_lock(&neigh_tbl_lock);
1460         for (tp = &neigh_tables; *tp; tp = &(*tp)->next) {
1461                 if (*tp == tbl) {
1462                         *tp = tbl->next;
1463                         break;
1464                 }
1465         }
1466         write_unlock(&neigh_tbl_lock);
1467
1468         neigh_hash_free(tbl->hash_buckets, tbl->hash_mask + 1);
1469         tbl->hash_buckets = NULL;
1470
1471         kfree(tbl->phash_buckets);
1472         tbl->phash_buckets = NULL;
1473
1474         remove_proc_entry(tbl->id, init_net.proc_net_stat);
1475
1476         free_percpu(tbl->stats);
1477         tbl->stats = NULL;
1478
1479         kmem_cache_destroy(tbl->kmem_cachep);
1480         tbl->kmem_cachep = NULL;
1481
1482         return 0;
1483 }
1484
1485 static int neigh_delete(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
1486 {
1487         struct net *net = sock_net(skb->sk);
1488         struct ndmsg *ndm;
1489         struct nlattr *dst_attr;
1490         struct neigh_table *tbl;
1491         struct net_device *dev = NULL;
1492         int err = -EINVAL;
1493
1494         if (nlmsg_len(nlh) < sizeof(*ndm))
1495                 goto out;
1496
1497         dst_attr = nlmsg_find_attr(nlh, sizeof(*ndm), NDA_DST);
1498         if (dst_attr == NULL)
1499                 goto out;
1500
1501         ndm = nlmsg_data(nlh);
1502         if (ndm->ndm_ifindex) {
1503                 dev = dev_get_by_index(net, ndm->ndm_ifindex);
1504                 if (dev == NULL) {
1505                         err = -ENODEV;
1506                         goto out;
1507                 }
1508         }
1509
1510         read_lock(&neigh_tbl_lock);
1511         for (tbl = neigh_tables; tbl; tbl = tbl->next) {
1512                 struct neighbour *neigh;
1513
1514                 if (tbl->family != ndm->ndm_family)
1515                         continue;
1516                 read_unlock(&neigh_tbl_lock);
1517
1518                 if (nla_len(dst_attr) < tbl->key_len)
1519                         goto out_dev_put;
1520
1521                 if (ndm->ndm_flags & NTF_PROXY) {
1522                         err = pneigh_delete(tbl, net, nla_data(dst_attr), dev);
1523                         goto out_dev_put;
1524                 }
1525
1526                 if (dev == NULL)
1527                         goto out_dev_put;
1528
1529                 neigh = neigh_lookup(tbl, nla_data(dst_attr), dev);
1530                 if (neigh == NULL) {
1531                         err = -ENOENT;
1532                         goto out_dev_put;
1533                 }
1534
1535                 err = neigh_update(neigh, NULL, NUD_FAILED,
1536                                    NEIGH_UPDATE_F_OVERRIDE |
1537                                    NEIGH_UPDATE_F_ADMIN);
1538                 neigh_release(neigh);
1539                 goto out_dev_put;
1540         }
1541         read_unlock(&neigh_tbl_lock);
1542         err = -EAFNOSUPPORT;
1543
1544 out_dev_put:
1545         if (dev)
1546                 dev_put(dev);
1547 out:
1548         return err;
1549 }
1550
1551 static int neigh_add(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
1552 {
1553         struct net *net = sock_net(skb->sk);
1554         struct ndmsg *ndm;
1555         struct nlattr *tb[NDA_MAX+1];
1556         struct neigh_table *tbl;
1557         struct net_device *dev = NULL;
1558         int err;
1559
1560         err = nlmsg_parse(nlh, sizeof(*ndm), tb, NDA_MAX, NULL);
1561         if (err < 0)
1562                 goto out;
1563
1564         err = -EINVAL;
1565         if (tb[NDA_DST] == NULL)
1566                 goto out;
1567
1568         ndm = nlmsg_data(nlh);
1569         if (ndm->ndm_ifindex) {
1570                 dev = dev_get_by_index(net, ndm->ndm_ifindex);
1571                 if (dev == NULL) {
1572                         err = -ENODEV;
1573                         goto out;
1574                 }
1575
1576                 if (tb[NDA_LLADDR] && nla_len(tb[NDA_LLADDR]) < dev->addr_len)
1577                         goto out_dev_put;
1578         }
1579
1580         read_lock(&neigh_tbl_lock);
1581         for (tbl = neigh_tables; tbl; tbl = tbl->next) {
1582                 int flags = NEIGH_UPDATE_F_ADMIN | NEIGH_UPDATE_F_OVERRIDE;
1583                 struct neighbour *neigh;
1584                 void *dst, *lladdr;
1585
1586                 if (tbl->family != ndm->ndm_family)
1587                         continue;
1588                 read_unlock(&neigh_tbl_lock);
1589
1590                 if (nla_len(tb[NDA_DST]) < tbl->key_len)
1591                         goto out_dev_put;
1592                 dst = nla_data(tb[NDA_DST]);
1593                 lladdr = tb[NDA_LLADDR] ? nla_data(tb[NDA_LLADDR]) : NULL;
1594
1595                 if (ndm->ndm_flags & NTF_PROXY) {
1596                         struct pneigh_entry *pn;
1597
1598                         err = -ENOBUFS;
1599                         pn = pneigh_lookup(tbl, net, dst, dev, 1);
1600                         if (pn) {
1601                                 pn->flags = ndm->ndm_flags;
1602                                 err = 0;
1603                         }
1604                         goto out_dev_put;
1605                 }
1606
1607                 if (dev == NULL)
1608                         goto out_dev_put;
1609
1610                 neigh = neigh_lookup(tbl, dst, dev);
1611                 if (neigh == NULL) {
1612                         if (!(nlh->nlmsg_flags & NLM_F_CREATE)) {
1613                                 err = -ENOENT;
1614                                 goto out_dev_put;
1615                         }
1616
1617                         neigh = __neigh_lookup_errno(tbl, dst, dev);
1618                         if (IS_ERR(neigh)) {
1619                                 err = PTR_ERR(neigh);
1620                                 goto out_dev_put;
1621                         }
1622                 } else {
1623                         if (nlh->nlmsg_flags & NLM_F_EXCL) {
1624                                 err = -EEXIST;
1625                                 neigh_release(neigh);
1626                                 goto out_dev_put;
1627                         }
1628
1629                         if (!(nlh->nlmsg_flags & NLM_F_REPLACE))
1630                                 flags &= ~NEIGH_UPDATE_F_OVERRIDE;
1631                 }
1632
1633                 err = neigh_update(neigh, lladdr, ndm->ndm_state, flags);
1634                 neigh_release(neigh);
1635                 goto out_dev_put;
1636         }
1637
1638         read_unlock(&neigh_tbl_lock);
1639         err = -EAFNOSUPPORT;
1640
1641 out_dev_put:
1642         if (dev)
1643                 dev_put(dev);
1644 out:
1645         return err;
1646 }
1647
1648 static int neightbl_fill_parms(struct sk_buff *skb, struct neigh_parms *parms)
1649 {
1650         struct nlattr *nest;
1651
1652         nest = nla_nest_start(skb, NDTA_PARMS);
1653         if (nest == NULL)
1654                 return -ENOBUFS;
1655
1656         if (parms->dev)
1657                 NLA_PUT_U32(skb, NDTPA_IFINDEX, parms->dev->ifindex);
1658
1659         NLA_PUT_U32(skb, NDTPA_REFCNT, atomic_read(&parms->refcnt));
1660         NLA_PUT_U32(skb, NDTPA_QUEUE_LEN, parms->queue_len);
1661         NLA_PUT_U32(skb, NDTPA_PROXY_QLEN, parms->proxy_qlen);
1662         NLA_PUT_U32(skb, NDTPA_APP_PROBES, parms->app_probes);
1663         NLA_PUT_U32(skb, NDTPA_UCAST_PROBES, parms->ucast_probes);
1664         NLA_PUT_U32(skb, NDTPA_MCAST_PROBES, parms->mcast_probes);
1665         NLA_PUT_MSECS(skb, NDTPA_REACHABLE_TIME, parms->reachable_time);
1666         NLA_PUT_MSECS(skb, NDTPA_BASE_REACHABLE_TIME,
1667                       parms->base_reachable_time);
1668         NLA_PUT_MSECS(skb, NDTPA_GC_STALETIME, parms->gc_staletime);
1669         NLA_PUT_MSECS(skb, NDTPA_DELAY_PROBE_TIME, parms->delay_probe_time);
1670         NLA_PUT_MSECS(skb, NDTPA_RETRANS_TIME, parms->retrans_time);
1671         NLA_PUT_MSECS(skb, NDTPA_ANYCAST_DELAY, parms->anycast_delay);
1672         NLA_PUT_MSECS(skb, NDTPA_PROXY_DELAY, parms->proxy_delay);
1673         NLA_PUT_MSECS(skb, NDTPA_LOCKTIME, parms->locktime);
1674
1675         return nla_nest_end(skb, nest);
1676
1677 nla_put_failure:
1678         return nla_nest_cancel(skb, nest);
1679 }
1680
1681 static int neightbl_fill_info(struct sk_buff *skb, struct neigh_table *tbl,
1682                               u32 pid, u32 seq, int type, int flags)
1683 {
1684         struct nlmsghdr *nlh;
1685         struct ndtmsg *ndtmsg;
1686
1687         nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndtmsg), flags);
1688         if (nlh == NULL)
1689                 return -EMSGSIZE;
1690
1691         ndtmsg = nlmsg_data(nlh);
1692
1693         read_lock_bh(&tbl->lock);
1694         ndtmsg->ndtm_family = tbl->family;
1695         ndtmsg->ndtm_pad1   = 0;
1696         ndtmsg->ndtm_pad2   = 0;
1697
1698         NLA_PUT_STRING(skb, NDTA_NAME, tbl->id);
1699         NLA_PUT_MSECS(skb, NDTA_GC_INTERVAL, tbl->gc_interval);
1700         NLA_PUT_U32(skb, NDTA_THRESH1, tbl->gc_thresh1);
1701         NLA_PUT_U32(skb, NDTA_THRESH2, tbl->gc_thresh2);
1702         NLA_PUT_U32(skb, NDTA_THRESH3, tbl->gc_thresh3);
1703
1704         {
1705                 unsigned long now = jiffies;
1706                 unsigned int flush_delta = now - tbl->last_flush;
1707                 unsigned int rand_delta = now - tbl->last_rand;
1708
1709                 struct ndt_config ndc = {
1710                         .ndtc_key_len           = tbl->key_len,
1711                         .ndtc_entry_size        = tbl->entry_size,
1712                         .ndtc_entries           = atomic_read(&tbl->entries),
1713                         .ndtc_last_flush        = jiffies_to_msecs(flush_delta),
1714                         .ndtc_last_rand         = jiffies_to_msecs(rand_delta),
1715                         .ndtc_hash_rnd          = tbl->hash_rnd,
1716                         .ndtc_hash_mask         = tbl->hash_mask,
1717                         .ndtc_hash_chain_gc     = tbl->hash_chain_gc,
1718                         .ndtc_proxy_qlen        = tbl->proxy_queue.qlen,
1719                 };
1720
1721                 NLA_PUT(skb, NDTA_CONFIG, sizeof(ndc), &ndc);
1722         }
1723
1724         {
1725                 int cpu;
1726                 struct ndt_stats ndst;
1727
1728                 memset(&ndst, 0, sizeof(ndst));
1729
1730                 for_each_possible_cpu(cpu) {
1731                         struct neigh_statistics *st;
1732
1733                         st = per_cpu_ptr(tbl->stats, cpu);
1734                         ndst.ndts_allocs                += st->allocs;
1735                         ndst.ndts_destroys              += st->destroys;
1736                         ndst.ndts_hash_grows            += st->hash_grows;
1737                         ndst.ndts_res_failed            += st->res_failed;
1738                         ndst.ndts_lookups               += st->lookups;
1739                         ndst.ndts_hits                  += st->hits;
1740                         ndst.ndts_rcv_probes_mcast      += st->rcv_probes_mcast;
1741                         ndst.ndts_rcv_probes_ucast      += st->rcv_probes_ucast;
1742                         ndst.ndts_periodic_gc_runs      += st->periodic_gc_runs;
1743                         ndst.ndts_forced_gc_runs        += st->forced_gc_runs;
1744                 }
1745
1746                 NLA_PUT(skb, NDTA_STATS, sizeof(ndst), &ndst);
1747         }
1748
1749         BUG_ON(tbl->parms.dev);
1750         if (neightbl_fill_parms(skb, &tbl->parms) < 0)
1751                 goto nla_put_failure;
1752
1753         read_unlock_bh(&tbl->lock);
1754         return nlmsg_end(skb, nlh);
1755
1756 nla_put_failure:
1757         read_unlock_bh(&tbl->lock);
1758         nlmsg_cancel(skb, nlh);
1759         return -EMSGSIZE;
1760 }
1761
1762 static int neightbl_fill_param_info(struct sk_buff *skb,
1763                                     struct neigh_table *tbl,
1764                                     struct neigh_parms *parms,
1765                                     u32 pid, u32 seq, int type,
1766                                     unsigned int flags)
1767 {
1768         struct ndtmsg *ndtmsg;
1769         struct nlmsghdr *nlh;
1770
1771         nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndtmsg), flags);
1772         if (nlh == NULL)
1773                 return -EMSGSIZE;
1774
1775         ndtmsg = nlmsg_data(nlh);
1776
1777         read_lock_bh(&tbl->lock);
1778         ndtmsg->ndtm_family = tbl->family;
1779         ndtmsg->ndtm_pad1   = 0;
1780         ndtmsg->ndtm_pad2   = 0;
1781
1782         if (nla_put_string(skb, NDTA_NAME, tbl->id) < 0 ||
1783             neightbl_fill_parms(skb, parms) < 0)
1784                 goto errout;
1785
1786         read_unlock_bh(&tbl->lock);
1787         return nlmsg_end(skb, nlh);
1788 errout:
1789         read_unlock_bh(&tbl->lock);
1790         nlmsg_cancel(skb, nlh);
1791         return -EMSGSIZE;
1792 }
1793
1794 static const struct nla_policy nl_neightbl_policy[NDTA_MAX+1] = {
1795         [NDTA_NAME]             = { .type = NLA_STRING },
1796         [NDTA_THRESH1]          = { .type = NLA_U32 },
1797         [NDTA_THRESH2]          = { .type = NLA_U32 },
1798         [NDTA_THRESH3]          = { .type = NLA_U32 },
1799         [NDTA_GC_INTERVAL]      = { .type = NLA_U64 },
1800         [NDTA_PARMS]            = { .type = NLA_NESTED },
1801 };
1802
1803 static const struct nla_policy nl_ntbl_parm_policy[NDTPA_MAX+1] = {
1804         [NDTPA_IFINDEX]                 = { .type = NLA_U32 },
1805         [NDTPA_QUEUE_LEN]               = { .type = NLA_U32 },
1806         [NDTPA_PROXY_QLEN]              = { .type = NLA_U32 },
1807         [NDTPA_APP_PROBES]              = { .type = NLA_U32 },
1808         [NDTPA_UCAST_PROBES]            = { .type = NLA_U32 },
1809         [NDTPA_MCAST_PROBES]            = { .type = NLA_U32 },
1810         [NDTPA_BASE_REACHABLE_TIME]     = { .type = NLA_U64 },
1811         [NDTPA_GC_STALETIME]            = { .type = NLA_U64 },
1812         [NDTPA_DELAY_PROBE_TIME]        = { .type = NLA_U64 },
1813         [NDTPA_RETRANS_TIME]            = { .type = NLA_U64 },
1814         [NDTPA_ANYCAST_DELAY]           = { .type = NLA_U64 },
1815         [NDTPA_PROXY_DELAY]             = { .type = NLA_U64 },
1816         [NDTPA_LOCKTIME]                = { .type = NLA_U64 },
1817 };
1818
1819 static int neightbl_set(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
1820 {
1821         struct net *net = sock_net(skb->sk);
1822         struct neigh_table *tbl;
1823         struct ndtmsg *ndtmsg;
1824         struct nlattr *tb[NDTA_MAX+1];
1825         int err;
1826
1827         err = nlmsg_parse(nlh, sizeof(*ndtmsg), tb, NDTA_MAX,
1828                           nl_neightbl_policy);
1829         if (err < 0)
1830                 goto errout;
1831
1832         if (tb[NDTA_NAME] == NULL) {
1833                 err = -EINVAL;
1834                 goto errout;
1835         }
1836
1837         ndtmsg = nlmsg_data(nlh);
1838         read_lock(&neigh_tbl_lock);
1839         for (tbl = neigh_tables; tbl; tbl = tbl->next) {
1840                 if (ndtmsg->ndtm_family && tbl->family != ndtmsg->ndtm_family)
1841                         continue;
1842
1843                 if (nla_strcmp(tb[NDTA_NAME], tbl->id) == 0)
1844                         break;
1845         }
1846
1847         if (tbl == NULL) {
1848                 err = -ENOENT;
1849                 goto errout_locked;
1850         }
1851
1852         /*
1853          * We acquire tbl->lock to be nice to the periodic timers and
1854          * make sure they always see a consistent set of values.
1855          */
1856         write_lock_bh(&tbl->lock);
1857
1858         if (tb[NDTA_PARMS]) {
1859                 struct nlattr *tbp[NDTPA_MAX+1];
1860                 struct neigh_parms *p;
1861                 int i, ifindex = 0;
1862
1863                 err = nla_parse_nested(tbp, NDTPA_MAX, tb[NDTA_PARMS],
1864                                        nl_ntbl_parm_policy);
1865                 if (err < 0)
1866                         goto errout_tbl_lock;
1867
1868                 if (tbp[NDTPA_IFINDEX])
1869                         ifindex = nla_get_u32(tbp[NDTPA_IFINDEX]);
1870
1871                 p = lookup_neigh_params(tbl, net, ifindex);
1872                 if (p == NULL) {
1873                         err = -ENOENT;
1874                         goto errout_tbl_lock;
1875                 }
1876
1877                 for (i = 1; i <= NDTPA_MAX; i++) {
1878                         if (tbp[i] == NULL)
1879                                 continue;
1880
1881                         switch (i) {
1882                         case NDTPA_QUEUE_LEN:
1883                                 p->queue_len = nla_get_u32(tbp[i]);
1884                                 break;
1885                         case NDTPA_PROXY_QLEN:
1886                                 p->proxy_qlen = nla_get_u32(tbp[i]);
1887                                 break;
1888                         case NDTPA_APP_PROBES:
1889                                 p->app_probes = nla_get_u32(tbp[i]);
1890                                 break;
1891                         case NDTPA_UCAST_PROBES:
1892                                 p->ucast_probes = nla_get_u32(tbp[i]);
1893                                 break;
1894                         case NDTPA_MCAST_PROBES:
1895                                 p->mcast_probes = nla_get_u32(tbp[i]);
1896                                 break;
1897                         case NDTPA_BASE_REACHABLE_TIME:
1898                                 p->base_reachable_time = nla_get_msecs(tbp[i]);
1899                                 break;
1900                         case NDTPA_GC_STALETIME:
1901                                 p->gc_staletime = nla_get_msecs(tbp[i]);
1902                                 break;
1903                         case NDTPA_DELAY_PROBE_TIME:
1904                                 p->delay_probe_time = nla_get_msecs(tbp[i]);
1905                                 break;
1906                         case NDTPA_RETRANS_TIME:
1907                                 p->retrans_time = nla_get_msecs(tbp[i]);
1908                                 break;
1909                         case NDTPA_ANYCAST_DELAY:
1910                                 p->anycast_delay = nla_get_msecs(tbp[i]);
1911                                 break;
1912                         case NDTPA_PROXY_DELAY:
1913                                 p->proxy_delay = nla_get_msecs(tbp[i]);
1914                                 break;
1915                         case NDTPA_LOCKTIME:
1916                                 p->locktime = nla_get_msecs(tbp[i]);
1917                                 break;
1918                         }
1919                 }
1920         }
1921
1922         if (tb[NDTA_THRESH1])
1923                 tbl->gc_thresh1 = nla_get_u32(tb[NDTA_THRESH1]);
1924
1925         if (tb[NDTA_THRESH2])
1926                 tbl->gc_thresh2 = nla_get_u32(tb[NDTA_THRESH2]);
1927
1928         if (tb[NDTA_THRESH3])
1929                 tbl->gc_thresh3 = nla_get_u32(tb[NDTA_THRESH3]);
1930
1931         if (tb[NDTA_GC_INTERVAL])
1932                 tbl->gc_interval = nla_get_msecs(tb[NDTA_GC_INTERVAL]);
1933
1934         err = 0;
1935
1936 errout_tbl_lock:
1937         write_unlock_bh(&tbl->lock);
1938 errout_locked:
1939         read_unlock(&neigh_tbl_lock);
1940 errout:
1941         return err;
1942 }
1943
1944 static int neightbl_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
1945 {
1946         struct net *net = sock_net(skb->sk);
1947         int family, tidx, nidx = 0;
1948         int tbl_skip = cb->args[0];
1949         int neigh_skip = cb->args[1];
1950         struct neigh_table *tbl;
1951
1952         family = ((struct rtgenmsg *) nlmsg_data(cb->nlh))->rtgen_family;
1953
1954         read_lock(&neigh_tbl_lock);
1955         for (tbl = neigh_tables, tidx = 0; tbl; tbl = tbl->next, tidx++) {
1956                 struct neigh_parms *p;
1957
1958                 if (tidx < tbl_skip || (family && tbl->family != family))
1959                         continue;
1960
1961                 if (neightbl_fill_info(skb, tbl, NETLINK_CB(cb->skb).pid,
1962                                        cb->nlh->nlmsg_seq, RTM_NEWNEIGHTBL,
1963                                        NLM_F_MULTI) <= 0)
1964                         break;
1965
1966                 for (nidx = 0, p = tbl->parms.next; p; p = p->next) {
1967                         if (!net_eq(neigh_parms_net(p), net))
1968                                 continue;
1969
1970                         if (nidx++ < neigh_skip)
1971                                 continue;
1972
1973                         if (neightbl_fill_param_info(skb, tbl, p,
1974                                                      NETLINK_CB(cb->skb).pid,
1975                                                      cb->nlh->nlmsg_seq,
1976                                                      RTM_NEWNEIGHTBL,
1977                                                      NLM_F_MULTI) <= 0)
1978                                 goto out;
1979                 }
1980
1981                 neigh_skip = 0;
1982         }
1983 out:
1984         read_unlock(&neigh_tbl_lock);
1985         cb->args[0] = tidx;
1986         cb->args[1] = nidx;
1987
1988         return skb->len;
1989 }
1990
1991 static int neigh_fill_info(struct sk_buff *skb, struct neighbour *neigh,
1992                            u32 pid, u32 seq, int type, unsigned int flags)
1993 {
1994         unsigned long now = jiffies;
1995         struct nda_cacheinfo ci;
1996         struct nlmsghdr *nlh;
1997         struct ndmsg *ndm;
1998
1999         nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndm), flags);
2000         if (nlh == NULL)
2001                 return -EMSGSIZE;
2002
2003         ndm = nlmsg_data(nlh);
2004         ndm->ndm_family  = neigh->ops->family;
2005         ndm->ndm_pad1    = 0;
2006         ndm->ndm_pad2    = 0;
2007         ndm->ndm_flags   = neigh->flags;
2008         ndm->ndm_type    = neigh->type;
2009         ndm->ndm_ifindex = neigh->dev->ifindex;
2010
2011         NLA_PUT(skb, NDA_DST, neigh->tbl->key_len, neigh->primary_key);
2012
2013         read_lock_bh(&neigh->lock);
2014         ndm->ndm_state   = neigh->nud_state;
2015         if ((neigh->nud_state & NUD_VALID) &&
2016             nla_put(skb, NDA_LLADDR, neigh->dev->addr_len, neigh->ha) < 0) {
2017                 read_unlock_bh(&neigh->lock);
2018                 goto nla_put_failure;
2019         }
2020
2021         ci.ndm_used      = now - neigh->used;
2022         ci.ndm_confirmed = now - neigh->confirmed;
2023         ci.ndm_updated   = now - neigh->updated;
2024         ci.ndm_refcnt    = atomic_read(&neigh->refcnt) - 1;
2025         read_unlock_bh(&neigh->lock);
2026
2027         NLA_PUT_U32(skb, NDA_PROBES, atomic_read(&neigh->probes));
2028         NLA_PUT(skb, NDA_CACHEINFO, sizeof(ci), &ci);
2029
2030         return nlmsg_end(skb, nlh);
2031
2032 nla_put_failure:
2033         nlmsg_cancel(skb, nlh);
2034         return -EMSGSIZE;
2035 }
2036
2037 static void neigh_update_notify(struct neighbour *neigh)
2038 {
2039         call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, neigh);
2040         __neigh_notify(neigh, RTM_NEWNEIGH, 0);
2041 }
2042
2043 static int neigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb,
2044                             struct netlink_callback *cb)
2045 {
2046         struct net * net = sock_net(skb->sk);
2047         struct neighbour *n;
2048         int rc, h, s_h = cb->args[1];
2049         int idx, s_idx = idx = cb->args[2];
2050
2051         read_lock_bh(&tbl->lock);
2052         for (h = 0; h <= tbl->hash_mask; h++) {
2053                 if (h < s_h)
2054                         continue;
2055                 if (h > s_h)
2056                         s_idx = 0;
2057                 for (n = tbl->hash_buckets[h], idx = 0; n; n = n->next) {
2058                         int lidx;
2059                         if (dev_net(n->dev) != net)
2060                                 continue;
2061                         lidx = idx++;
2062                         if (lidx < s_idx)
2063                                 continue;
2064                         if (neigh_fill_info(skb, n, NETLINK_CB(cb->skb).pid,
2065                                             cb->nlh->nlmsg_seq,
2066                                             RTM_NEWNEIGH,
2067                                             NLM_F_MULTI) <= 0) {
2068                                 read_unlock_bh(&tbl->lock);
2069                                 rc = -1;
2070                                 goto out;
2071                         }
2072                 }
2073         }
2074         read_unlock_bh(&tbl->lock);
2075         rc = skb->len;
2076 out:
2077         cb->args[1] = h;
2078         cb->args[2] = idx;
2079         return rc;
2080 }
2081
2082 static int neigh_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
2083 {
2084         struct neigh_table *tbl;
2085         int t, family, s_t;
2086
2087         read_lock(&neigh_tbl_lock);
2088         family = ((struct rtgenmsg *) nlmsg_data(cb->nlh))->rtgen_family;
2089         s_t = cb->args[0];
2090
2091         for (tbl = neigh_tables, t = 0; tbl; tbl = tbl->next, t++) {
2092                 if (t < s_t || (family && tbl->family != family))
2093                         continue;
2094                 if (t > s_t)
2095                         memset(&cb->args[1], 0, sizeof(cb->args) -
2096                                                 sizeof(cb->args[0]));
2097                 if (neigh_dump_table(tbl, skb, cb) < 0)
2098                         break;
2099         }
2100         read_unlock(&neigh_tbl_lock);
2101
2102         cb->args[0] = t;
2103         return skb->len;
2104 }
2105
2106 void neigh_for_each(struct neigh_table *tbl, void (*cb)(struct neighbour *, void *), void *cookie)
2107 {
2108         int chain;
2109
2110         read_lock_bh(&tbl->lock);
2111         for (chain = 0; chain <= tbl->hash_mask; chain++) {
2112                 struct neighbour *n;
2113
2114                 for (n = tbl->hash_buckets[chain]; n; n = n->next)
2115                         cb(n, cookie);
2116         }
2117         read_unlock_bh(&tbl->lock);
2118 }
2119 EXPORT_SYMBOL(neigh_for_each);
2120
2121 /* The tbl->lock must be held as a writer and BH disabled. */
2122 void __neigh_for_each_release(struct neigh_table *tbl,
2123                               int (*cb)(struct neighbour *))
2124 {
2125         int chain;
2126
2127         for (chain = 0; chain <= tbl->hash_mask; chain++) {
2128                 struct neighbour *n, **np;
2129
2130                 np = &tbl->hash_buckets[chain];
2131                 while ((n = *np) != NULL) {
2132                         int release;
2133
2134                         write_lock(&n->lock);
2135                         release = cb(n);
2136                         if (release) {
2137                                 *np = n->next;
2138                                 n->dead = 1;
2139                         } else
2140                                 np = &n->next;
2141                         write_unlock(&n->lock);
2142                         if (release)
2143                                 neigh_cleanup_and_release(n);
2144                 }
2145         }
2146 }
2147 EXPORT_SYMBOL(__neigh_for_each_release);
2148
2149 #ifdef CONFIG_PROC_FS
2150
2151 static struct neighbour *neigh_get_first(struct seq_file *seq)
2152 {
2153         struct neigh_seq_state *state = seq->private;
2154         struct net *net = seq_file_net(seq);
2155         struct neigh_table *tbl = state->tbl;
2156         struct neighbour *n = NULL;
2157         int bucket = state->bucket;
2158
2159         state->flags &= ~NEIGH_SEQ_IS_PNEIGH;
2160         for (bucket = 0; bucket <= tbl->hash_mask; bucket++) {
2161                 n = tbl->hash_buckets[bucket];
2162
2163                 while (n) {
2164                         if (!net_eq(dev_net(n->dev), net))
2165                                 goto next;
2166                         if (state->neigh_sub_iter) {
2167                                 loff_t fakep = 0;
2168                                 void *v;
2169
2170                                 v = state->neigh_sub_iter(state, n, &fakep);
2171                                 if (!v)
2172                                         goto next;
2173                         }
2174                         if (!(state->flags & NEIGH_SEQ_SKIP_NOARP))
2175                                 break;
2176                         if (n->nud_state & ~NUD_NOARP)
2177                                 break;
2178                 next:
2179                         n = n->next;
2180                 }
2181
2182                 if (n)
2183                         break;
2184         }
2185         state->bucket = bucket;
2186
2187         return n;
2188 }
2189
2190 static struct neighbour *neigh_get_next(struct seq_file *seq,
2191                                         struct neighbour *n,
2192                                         loff_t *pos)
2193 {
2194         struct neigh_seq_state *state = seq->private;
2195         struct net *net = seq_file_net(seq);
2196         struct neigh_table *tbl = state->tbl;
2197
2198         if (state->neigh_sub_iter) {
2199                 void *v = state->neigh_sub_iter(state, n, pos);
2200                 if (v)
2201                         return n;
2202         }
2203         n = n->next;
2204
2205         while (1) {
2206                 while (n) {
2207                         if (!net_eq(dev_net(n->dev), net))
2208                                 goto next;
2209                         if (state->neigh_sub_iter) {
2210                                 void *v = state->neigh_sub_iter(state, n, pos);
2211                                 if (v)
2212                                         return n;
2213                                 goto next;
2214                         }
2215                         if (!(state->flags & NEIGH_SEQ_SKIP_NOARP))
2216                                 break;
2217
2218                         if (n->nud_state & ~NUD_NOARP)
2219                                 break;
2220                 next:
2221                         n = n->next;
2222                 }
2223
2224                 if (n)
2225                         break;
2226
2227                 if (++state->bucket > tbl->hash_mask)
2228                         break;
2229
2230                 n = tbl->hash_buckets[state->bucket];
2231         }
2232
2233         if (n && pos)
2234                 --(*pos);
2235         return n;
2236 }
2237
2238 static struct neighbour *neigh_get_idx(struct seq_file *seq, loff_t *pos)
2239 {
2240         struct neighbour *n = neigh_get_first(seq);
2241
2242         if (n) {
2243                 while (*pos) {
2244                         n = neigh_get_next(seq, n, pos);
2245                         if (!n)
2246                                 break;
2247                 }
2248         }
2249         return *pos ? NULL : n;
2250 }
2251
2252 static struct pneigh_entry *pneigh_get_first(struct seq_file *seq)
2253 {
2254         struct neigh_seq_state *state = seq->private;
2255         struct net *net = seq_file_net(seq);
2256         struct neigh_table *tbl = state->tbl;
2257         struct pneigh_entry *pn = NULL;
2258         int bucket = state->bucket;
2259
2260         state->flags |= NEIGH_SEQ_IS_PNEIGH;
2261         for (bucket = 0; bucket <= PNEIGH_HASHMASK; bucket++) {
2262                 pn = tbl->phash_buckets[bucket];
2263                 while (pn && !net_eq(pneigh_net(pn), net))
2264                         pn = pn->next;
2265                 if (pn)
2266                         break;
2267         }
2268         state->bucket = bucket;
2269
2270         return pn;
2271 }
2272
2273 static struct pneigh_entry *pneigh_get_next(struct seq_file *seq,
2274                                             struct pneigh_entry *pn,
2275                                             loff_t *pos)
2276 {
2277         struct neigh_seq_state *state = seq->private;
2278         struct net *net = seq_file_net(seq);
2279         struct neigh_table *tbl = state->tbl;
2280
2281         pn = pn->next;
2282         while (!pn) {
2283                 if (++state->bucket > PNEIGH_HASHMASK)
2284                         break;
2285                 pn = tbl->phash_buckets[state->bucket];
2286                 while (pn && !net_eq(pneigh_net(pn), net))
2287                         pn = pn->next;
2288                 if (pn)
2289                         break;
2290         }
2291
2292         if (pn && pos)
2293                 --(*pos);
2294
2295         return pn;
2296 }
2297
2298 static struct pneigh_entry *pneigh_get_idx(struct seq_file *seq, loff_t *pos)
2299 {
2300         struct pneigh_entry *pn = pneigh_get_first(seq);
2301
2302         if (pn) {
2303                 while (*pos) {
2304                         pn = pneigh_get_next(seq, pn, pos);
2305                         if (!pn)
2306                                 break;
2307                 }
2308         }
2309         return *pos ? NULL : pn;
2310 }
2311
2312 static void *neigh_get_idx_any(struct seq_file *seq, loff_t *pos)
2313 {
2314         struct neigh_seq_state *state = seq->private;
2315         void *rc;
2316
2317         rc = neigh_get_idx(seq, pos);
2318         if (!rc && !(state->flags & NEIGH_SEQ_NEIGH_ONLY))
2319                 rc = pneigh_get_idx(seq, pos);
2320
2321         return rc;
2322 }
2323
2324 void *neigh_seq_start(struct seq_file *seq, loff_t *pos, struct neigh_table *tbl, unsigned int neigh_seq_flags)
2325         __acquires(tbl->lock)
2326 {
2327         struct neigh_seq_state *state = seq->private;
2328         loff_t pos_minus_one;
2329
2330         state->tbl = tbl;
2331         state->bucket = 0;
2332         state->flags = (neigh_seq_flags & ~NEIGH_SEQ_IS_PNEIGH);
2333
2334         read_lock_bh(&tbl->lock);
2335
2336         pos_minus_one = *pos - 1;
2337         return *pos ? neigh_get_idx_any(seq, &pos_minus_one) : SEQ_START_TOKEN;
2338 }
2339 EXPORT_SYMBOL(neigh_seq_start);
2340
2341 void *neigh_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2342 {
2343         struct neigh_seq_state *state;
2344         void *rc;
2345
2346         if (v == SEQ_START_TOKEN) {
2347                 rc = neigh_get_idx(seq, pos);
2348                 goto out;
2349         }
2350
2351         state = seq->private;
2352         if (!(state->flags & NEIGH_SEQ_IS_PNEIGH)) {
2353                 rc = neigh_get_next(seq, v, NULL);
2354                 if (rc)
2355                         goto out;
2356                 if (!(state->flags & NEIGH_SEQ_NEIGH_ONLY))
2357                         rc = pneigh_get_first(seq);
2358         } else {
2359                 BUG_ON(state->flags & NEIGH_SEQ_NEIGH_ONLY);
2360                 rc = pneigh_get_next(seq, v, NULL);
2361         }
2362 out:
2363         ++(*pos);
2364         return rc;
2365 }
2366 EXPORT_SYMBOL(neigh_seq_next);
2367
2368 void neigh_seq_stop(struct seq_file *seq, void *v)
2369         __releases(tbl->lock)
2370 {
2371         struct neigh_seq_state *state = seq->private;
2372         struct neigh_table *tbl = state->tbl;
2373
2374         read_unlock_bh(&tbl->lock);
2375 }
2376 EXPORT_SYMBOL(neigh_seq_stop);
2377
2378 /* statistics via seq_file */
2379
2380 static void *neigh_stat_seq_start(struct seq_file *seq, loff_t *pos)
2381 {
2382         struct proc_dir_entry *pde = seq->private;
2383         struct neigh_table *tbl = pde->data;
2384         int cpu;
2385
2386         if (*pos == 0)
2387                 return SEQ_START_TOKEN;
2388
2389         for (cpu = *pos-1; cpu < NR_CPUS; ++cpu) {
2390                 if (!cpu_possible(cpu))
2391                         continue;
2392                 *pos = cpu+1;
2393                 return per_cpu_ptr(tbl->stats, cpu);
2394         }
2395         return NULL;
2396 }
2397
2398 static void *neigh_stat_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2399 {
2400         struct proc_dir_entry *pde = seq->private;
2401         struct neigh_table *tbl = pde->data;
2402         int cpu;
2403
2404         for (cpu = *pos; cpu < NR_CPUS; ++cpu) {
2405                 if (!cpu_possible(cpu))
2406                         continue;
2407                 *pos = cpu+1;
2408                 return per_cpu_ptr(tbl->stats, cpu);
2409         }
2410         return NULL;
2411 }
2412
2413 static void neigh_stat_seq_stop(struct seq_file *seq, void *v)
2414 {
2415
2416 }
2417
2418 static int neigh_stat_seq_show(struct seq_file *seq, void *v)
2419 {
2420         struct proc_dir_entry *pde = seq->private;
2421         struct neigh_table *tbl = pde->data;
2422         struct neigh_statistics *st = v;
2423
2424         if (v == SEQ_START_TOKEN) {
2425                 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");
2426                 return 0;
2427         }
2428
2429         seq_printf(seq, "%08x  %08lx %08lx %08lx  %08lx %08lx  %08lx  "
2430                         "%08lx %08lx  %08lx %08lx\n",
2431                    atomic_read(&tbl->entries),
2432
2433                    st->allocs,
2434                    st->destroys,
2435                    st->hash_grows,
2436
2437                    st->lookups,
2438                    st->hits,
2439
2440                    st->res_failed,
2441
2442                    st->rcv_probes_mcast,
2443                    st->rcv_probes_ucast,
2444
2445                    st->periodic_gc_runs,
2446                    st->forced_gc_runs
2447                    );
2448
2449         return 0;
2450 }
2451
2452 static const struct seq_operations neigh_stat_seq_ops = {
2453         .start  = neigh_stat_seq_start,
2454         .next   = neigh_stat_seq_next,
2455         .stop   = neigh_stat_seq_stop,
2456         .show   = neigh_stat_seq_show,
2457 };
2458
2459 static int neigh_stat_seq_open(struct inode *inode, struct file *file)
2460 {
2461         int ret = seq_open(file, &neigh_stat_seq_ops);
2462
2463         if (!ret) {
2464                 struct seq_file *sf = file->private_data;
2465                 sf->private = PDE(inode);
2466         }
2467         return ret;
2468 };
2469
2470 static const struct file_operations neigh_stat_seq_fops = {
2471         .owner   = THIS_MODULE,
2472         .open    = neigh_stat_seq_open,
2473         .read    = seq_read,
2474         .llseek  = seq_lseek,
2475         .release = seq_release,
2476 };
2477
2478 #endif /* CONFIG_PROC_FS */
2479
2480 static inline size_t neigh_nlmsg_size(void)
2481 {
2482         return NLMSG_ALIGN(sizeof(struct ndmsg))
2483                + nla_total_size(MAX_ADDR_LEN) /* NDA_DST */
2484                + nla_total_size(MAX_ADDR_LEN) /* NDA_LLADDR */
2485                + nla_total_size(sizeof(struct nda_cacheinfo))
2486                + nla_total_size(4); /* NDA_PROBES */
2487 }
2488
2489 static void __neigh_notify(struct neighbour *n, int type, int flags)
2490 {
2491         struct net *net = dev_net(n->dev);
2492         struct sk_buff *skb;
2493         int err = -ENOBUFS;
2494
2495         skb = nlmsg_new(neigh_nlmsg_size(), GFP_ATOMIC);
2496         if (skb == NULL)
2497                 goto errout;
2498
2499         err = neigh_fill_info(skb, n, 0, 0, type, flags);
2500         if (err < 0) {
2501                 /* -EMSGSIZE implies BUG in neigh_nlmsg_size() */
2502                 WARN_ON(err == -EMSGSIZE);
2503                 kfree_skb(skb);
2504                 goto errout;
2505         }
2506         err = rtnl_notify(skb, net, 0, RTNLGRP_NEIGH, NULL, GFP_ATOMIC);
2507 errout:
2508         if (err < 0)
2509                 rtnl_set_sk_err(net, RTNLGRP_NEIGH, err);
2510 }
2511
2512 #ifdef CONFIG_ARPD
2513 void neigh_app_ns(struct neighbour *n)
2514 {
2515         __neigh_notify(n, RTM_GETNEIGH, NLM_F_REQUEST);
2516 }
2517 #endif /* CONFIG_ARPD */
2518
2519 #ifdef CONFIG_SYSCTL
2520
2521 static struct neigh_sysctl_table {
2522         struct ctl_table_header *sysctl_header;
2523         struct ctl_table neigh_vars[__NET_NEIGH_MAX];
2524         char *dev_name;
2525 } neigh_sysctl_template __read_mostly = {
2526         .neigh_vars = {
2527                 {
2528                         .ctl_name       = NET_NEIGH_MCAST_SOLICIT,
2529                         .procname       = "mcast_solicit",
2530                         .maxlen         = sizeof(int),
2531                         .mode           = 0644,
2532                         .proc_handler   = &proc_dointvec,
2533                 },
2534                 {
2535                         .ctl_name       = NET_NEIGH_UCAST_SOLICIT,
2536                         .procname       = "ucast_solicit",
2537                         .maxlen         = sizeof(int),
2538                         .mode           = 0644,
2539                         .proc_handler   = &proc_dointvec,
2540                 },
2541                 {
2542                         .ctl_name       = NET_NEIGH_APP_SOLICIT,
2543                         .procname       = "app_solicit",
2544                         .maxlen         = sizeof(int),
2545                         .mode           = 0644,
2546                         .proc_handler   = &proc_dointvec,
2547                 },
2548                 {
2549                         .procname       = "retrans_time",
2550                         .maxlen         = sizeof(int),
2551                         .mode           = 0644,
2552                         .proc_handler   = &proc_dointvec_userhz_jiffies,
2553                 },
2554                 {
2555                         .ctl_name       = NET_NEIGH_REACHABLE_TIME,
2556                         .procname       = "base_reachable_time",
2557                         .maxlen         = sizeof(int),
2558                         .mode           = 0644,
2559                         .proc_handler   = &proc_dointvec_jiffies,
2560                         .strategy       = &sysctl_jiffies,
2561                 },
2562                 {
2563                         .ctl_name       = NET_NEIGH_DELAY_PROBE_TIME,
2564                         .procname       = "delay_first_probe_time",
2565                         .maxlen         = sizeof(int),
2566                         .mode           = 0644,
2567                         .proc_handler   = &proc_dointvec_jiffies,
2568                         .strategy       = &sysctl_jiffies,
2569                 },
2570                 {
2571                         .ctl_name       = NET_NEIGH_GC_STALE_TIME,
2572                         .procname       = "gc_stale_time",
2573                         .maxlen         = sizeof(int),
2574                         .mode           = 0644,
2575                         .proc_handler   = &proc_dointvec_jiffies,
2576                         .strategy       = &sysctl_jiffies,
2577                 },
2578                 {
2579                         .ctl_name       = NET_NEIGH_UNRES_QLEN,
2580                         .procname       = "unres_qlen",
2581                         .maxlen         = sizeof(int),
2582                         .mode           = 0644,
2583                         .proc_handler   = &proc_dointvec,
2584                 },
2585                 {
2586                         .ctl_name       = NET_NEIGH_PROXY_QLEN,
2587                         .procname       = "proxy_qlen",
2588                         .maxlen         = sizeof(int),
2589                         .mode           = 0644,
2590                         .proc_handler   = &proc_dointvec,
2591                 },
2592                 {
2593                         .procname       = "anycast_delay",
2594                         .maxlen         = sizeof(int),
2595                         .mode           = 0644,
2596                         .proc_handler   = &proc_dointvec_userhz_jiffies,
2597                 },
2598                 {
2599                         .procname       = "proxy_delay",
2600                         .maxlen         = sizeof(int),
2601                         .mode           = 0644,
2602                         .proc_handler   = &proc_dointvec_userhz_jiffies,
2603                 },
2604                 {
2605                         .procname       = "locktime",
2606                         .maxlen         = sizeof(int),
2607                         .mode           = 0644,
2608                         .proc_handler   = &proc_dointvec_userhz_jiffies,
2609                 },
2610                 {
2611                         .ctl_name       = NET_NEIGH_RETRANS_TIME_MS,
2612                         .procname       = "retrans_time_ms",
2613                         .maxlen         = sizeof(int),
2614                         .mode           = 0644,
2615                         .proc_handler   = &proc_dointvec_ms_jiffies,
2616                         .strategy       = &sysctl_ms_jiffies,
2617                 },
2618                 {
2619                         .ctl_name       = NET_NEIGH_REACHABLE_TIME_MS,
2620                         .procname       = "base_reachable_time_ms",
2621                         .maxlen         = sizeof(int),
2622                         .mode           = 0644,
2623                         .proc_handler   = &proc_dointvec_ms_jiffies,
2624                         .strategy       = &sysctl_ms_jiffies,
2625                 },
2626                 {
2627                         .ctl_name       = NET_NEIGH_GC_INTERVAL,
2628                         .procname       = "gc_interval",
2629                         .maxlen         = sizeof(int),
2630                         .mode           = 0644,
2631                         .proc_handler   = &proc_dointvec_jiffies,
2632                         .strategy       = &sysctl_jiffies,
2633                 },
2634                 {
2635                         .ctl_name       = NET_NEIGH_GC_THRESH1,
2636                         .procname       = "gc_thresh1",
2637                         .maxlen         = sizeof(int),
2638                         .mode           = 0644,
2639                         .proc_handler   = &proc_dointvec,
2640                 },
2641                 {
2642                         .ctl_name       = NET_NEIGH_GC_THRESH2,
2643                         .procname       = "gc_thresh2",
2644                         .maxlen         = sizeof(int),
2645                         .mode           = 0644,
2646                         .proc_handler   = &proc_dointvec,
2647                 },
2648                 {
2649                         .ctl_name       = NET_NEIGH_GC_THRESH3,
2650                         .procname       = "gc_thresh3",
2651                         .maxlen         = sizeof(int),
2652                         .mode           = 0644,
2653                         .proc_handler   = &proc_dointvec,
2654                 },
2655                 {},
2656         },
2657 };
2658
2659 int neigh_sysctl_register(struct net_device *dev, struct neigh_parms *p,
2660                           int p_id, int pdev_id, char *p_name,
2661                           proc_handler *handler, ctl_handler *strategy)
2662 {
2663         struct neigh_sysctl_table *t;
2664         const char *dev_name_source = NULL;
2665
2666 #define NEIGH_CTL_PATH_ROOT     0
2667 #define NEIGH_CTL_PATH_PROTO    1
2668 #define NEIGH_CTL_PATH_NEIGH    2
2669 #define NEIGH_CTL_PATH_DEV      3
2670
2671         struct ctl_path neigh_path[] = {
2672                 { .procname = "net",     .ctl_name = CTL_NET, },
2673                 { .procname = "proto",   .ctl_name = 0, },
2674                 { .procname = "neigh",   .ctl_name = 0, },
2675                 { .procname = "default", .ctl_name = NET_PROTO_CONF_DEFAULT, },
2676                 { },
2677         };
2678
2679         t = kmemdup(&neigh_sysctl_template, sizeof(*t), GFP_KERNEL);
2680         if (!t)
2681                 goto err;
2682
2683         t->neigh_vars[0].data  = &p->mcast_probes;
2684         t->neigh_vars[1].data  = &p->ucast_probes;
2685         t->neigh_vars[2].data  = &p->app_probes;
2686         t->neigh_vars[3].data  = &p->retrans_time;
2687         t->neigh_vars[4].data  = &p->base_reachable_time;
2688         t->neigh_vars[5].data  = &p->delay_probe_time;
2689         t->neigh_vars[6].data  = &p->gc_staletime;
2690         t->neigh_vars[7].data  = &p->queue_len;
2691         t->neigh_vars[8].data  = &p->proxy_qlen;
2692         t->neigh_vars[9].data  = &p->anycast_delay;
2693         t->neigh_vars[10].data = &p->proxy_delay;
2694         t->neigh_vars[11].data = &p->locktime;
2695         t->neigh_vars[12].data  = &p->retrans_time;
2696         t->neigh_vars[13].data  = &p->base_reachable_time;
2697
2698         if (dev) {
2699                 dev_name_source = dev->name;
2700                 neigh_path[NEIGH_CTL_PATH_DEV].ctl_name = dev->ifindex;
2701                 /* Terminate the table early */
2702                 memset(&t->neigh_vars[14], 0, sizeof(t->neigh_vars[14]));
2703         } else {
2704                 dev_name_source = neigh_path[NEIGH_CTL_PATH_DEV].procname;
2705                 t->neigh_vars[14].data = (int *)(p + 1);
2706                 t->neigh_vars[15].data = (int *)(p + 1) + 1;
2707                 t->neigh_vars[16].data = (int *)(p + 1) + 2;
2708                 t->neigh_vars[17].data = (int *)(p + 1) + 3;
2709         }
2710
2711
2712         if (handler || strategy) {
2713                 /* RetransTime */
2714                 t->neigh_vars[3].proc_handler = handler;
2715                 t->neigh_vars[3].strategy = strategy;
2716                 t->neigh_vars[3].extra1 = dev;
2717                 if (!strategy)
2718                         t->neigh_vars[3].ctl_name = CTL_UNNUMBERED;
2719                 /* ReachableTime */
2720                 t->neigh_vars[4].proc_handler = handler;
2721                 t->neigh_vars[4].strategy = strategy;
2722                 t->neigh_vars[4].extra1 = dev;
2723                 if (!strategy)
2724                         t->neigh_vars[4].ctl_name = CTL_UNNUMBERED;
2725                 /* RetransTime (in milliseconds)*/
2726                 t->neigh_vars[12].proc_handler = handler;
2727                 t->neigh_vars[12].strategy = strategy;
2728                 t->neigh_vars[12].extra1 = dev;
2729                 if (!strategy)
2730                         t->neigh_vars[12].ctl_name = CTL_UNNUMBERED;
2731                 /* ReachableTime (in milliseconds) */
2732                 t->neigh_vars[13].proc_handler = handler;
2733                 t->neigh_vars[13].strategy = strategy;
2734                 t->neigh_vars[13].extra1 = dev;
2735                 if (!strategy)
2736                         t->neigh_vars[13].ctl_name = CTL_UNNUMBERED;
2737         }
2738
2739         t->dev_name = kstrdup(dev_name_source, GFP_KERNEL);
2740         if (!t->dev_name)
2741                 goto free;
2742
2743         neigh_path[NEIGH_CTL_PATH_DEV].procname = t->dev_name;
2744         neigh_path[NEIGH_CTL_PATH_NEIGH].ctl_name = pdev_id;
2745         neigh_path[NEIGH_CTL_PATH_PROTO].procname = p_name;
2746         neigh_path[NEIGH_CTL_PATH_PROTO].ctl_name = p_id;
2747
2748         t->sysctl_header =
2749                 register_net_sysctl_table(neigh_parms_net(p), neigh_path, t->neigh_vars);
2750         if (!t->sysctl_header)
2751                 goto free_procname;
2752
2753         p->sysctl_table = t;
2754         return 0;
2755
2756 free_procname:
2757         kfree(t->dev_name);
2758 free:
2759         kfree(t);
2760 err:
2761         return -ENOBUFS;
2762 }
2763
2764 void neigh_sysctl_unregister(struct neigh_parms *p)
2765 {
2766         if (p->sysctl_table) {
2767                 struct neigh_sysctl_table *t = p->sysctl_table;
2768                 p->sysctl_table = NULL;
2769                 unregister_sysctl_table(t->sysctl_header);
2770                 kfree(t->dev_name);
2771                 kfree(t);
2772         }
2773 }
2774
2775 #endif  /* CONFIG_SYSCTL */
2776
2777 static int __init neigh_init(void)
2778 {
2779         rtnl_register(PF_UNSPEC, RTM_NEWNEIGH, neigh_add, NULL);
2780         rtnl_register(PF_UNSPEC, RTM_DELNEIGH, neigh_delete, NULL);
2781         rtnl_register(PF_UNSPEC, RTM_GETNEIGH, NULL, neigh_dump_info);
2782
2783         rtnl_register(PF_UNSPEC, RTM_GETNEIGHTBL, NULL, neightbl_dump_info);
2784         rtnl_register(PF_UNSPEC, RTM_SETNEIGHTBL, neightbl_set, NULL);
2785
2786         return 0;
2787 }
2788
2789 subsys_initcall(neigh_init);
2790
2791 EXPORT_SYMBOL(__neigh_event_send);
2792 EXPORT_SYMBOL(neigh_changeaddr);
2793 EXPORT_SYMBOL(neigh_compat_output);
2794 EXPORT_SYMBOL(neigh_connected_output);
2795 EXPORT_SYMBOL(neigh_create);
2796 EXPORT_SYMBOL(neigh_destroy);
2797 EXPORT_SYMBOL(neigh_event_ns);
2798 EXPORT_SYMBOL(neigh_ifdown);
2799 EXPORT_SYMBOL(neigh_lookup);
2800 EXPORT_SYMBOL(neigh_lookup_nodev);
2801 EXPORT_SYMBOL(neigh_parms_alloc);
2802 EXPORT_SYMBOL(neigh_parms_release);
2803 EXPORT_SYMBOL(neigh_rand_reach_time);
2804 EXPORT_SYMBOL(neigh_resolve_output);
2805 EXPORT_SYMBOL(neigh_table_clear);
2806 EXPORT_SYMBOL(neigh_table_init);
2807 EXPORT_SYMBOL(neigh_table_init_no_netlink);
2808 EXPORT_SYMBOL(neigh_update);
2809 EXPORT_SYMBOL(pneigh_enqueue);
2810 EXPORT_SYMBOL(pneigh_lookup);
2811
2812 #ifdef CONFIG_ARPD
2813 EXPORT_SYMBOL(neigh_app_ns);
2814 #endif
2815 #ifdef CONFIG_SYSCTL
2816 EXPORT_SYMBOL(neigh_sysctl_register);
2817 EXPORT_SYMBOL(neigh_sysctl_unregister);
2818 #endif