| 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
| 2 | /* |
| 3 | * Generic address resolution entity |
| 4 | * |
| 5 | * Authors: |
| 6 | * Pedro Roque <roque@di.fc.ul.pt> |
| 7 | * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> |
| 8 | * |
| 9 | * Fixes: |
| 10 | * Vitaly E. Lavrov releasing NULL neighbor in neigh_add. |
| 11 | * Harald Welte Add neighbour cache statistics like rtstat |
| 12 | */ |
| 13 | |
| 14 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| 15 | |
| 16 | #include <linux/slab.h> |
| 17 | #include <linux/kmemleak.h> |
| 18 | #include <linux/types.h> |
| 19 | #include <linux/kernel.h> |
| 20 | #include <linux/module.h> |
| 21 | #include <linux/socket.h> |
| 22 | #include <linux/netdevice.h> |
| 23 | #include <linux/proc_fs.h> |
| 24 | #ifdef CONFIG_SYSCTL |
| 25 | #include <linux/sysctl.h> |
| 26 | #endif |
| 27 | #include <linux/times.h> |
| 28 | #include <net/net_namespace.h> |
| 29 | #include <net/neighbour.h> |
| 30 | #include <net/arp.h> |
| 31 | #include <net/dst.h> |
| 32 | #include <net/sock.h> |
| 33 | #include <net/netevent.h> |
| 34 | #include <net/netlink.h> |
| 35 | #include <linux/rtnetlink.h> |
| 36 | #include <linux/random.h> |
| 37 | #include <linux/string.h> |
| 38 | #include <linux/log2.h> |
| 39 | #include <linux/inetdevice.h> |
| 40 | #include <net/addrconf.h> |
| 41 | |
| 42 | #include <trace/events/neigh.h> |
| 43 | |
| 44 | #define NEIGH_DEBUG 1 |
| 45 | #define neigh_dbg(level, fmt, ...) \ |
| 46 | do { \ |
| 47 | if (level <= NEIGH_DEBUG) \ |
| 48 | pr_debug(fmt, ##__VA_ARGS__); \ |
| 49 | } while (0) |
| 50 | |
| 51 | #define PNEIGH_HASHMASK 0xF |
| 52 | |
| 53 | static void neigh_timer_handler(struct timer_list *t); |
| 54 | static void __neigh_notify(struct neighbour *n, int type, int flags, |
| 55 | u32 pid); |
| 56 | static void neigh_update_notify(struct neighbour *neigh, u32 nlmsg_pid); |
| 57 | static int pneigh_ifdown_and_unlock(struct neigh_table *tbl, |
| 58 | struct net_device *dev); |
| 59 | |
| 60 | #ifdef CONFIG_PROC_FS |
| 61 | static const struct seq_operations neigh_stat_seq_ops; |
| 62 | #endif |
| 63 | |
| 64 | /* |
| 65 | Neighbour hash table buckets are protected with rwlock tbl->lock. |
| 66 | |
| 67 | - All the scans/updates to hash buckets MUST be made under this lock. |
| 68 | - NOTHING clever should be made under this lock: no callbacks |
| 69 | to protocol backends, no attempts to send something to network. |
| 70 | It will result in deadlocks, if backend/driver wants to use neighbour |
| 71 | cache. |
| 72 | - If the entry requires some non-trivial actions, increase |
| 73 | its reference count and release table lock. |
| 74 | |
| 75 | Neighbour entries are protected: |
| 76 | - with reference count. |
| 77 | - with rwlock neigh->lock |
| 78 | |
| 79 | Reference count prevents destruction. |
| 80 | |
| 81 | neigh->lock mainly serializes ll address data and its validity state. |
| 82 | However, the same lock is used to protect another entry fields: |
| 83 | - timer |
| 84 | - resolution queue |
| 85 | |
| 86 | Again, nothing clever shall be made under neigh->lock, |
| 87 | the most complicated procedure, which we allow is dev->hard_header. |
| 88 | It is supposed, that dev->hard_header is simplistic and does |
| 89 | not make callbacks to neighbour tables. |
| 90 | */ |
| 91 | |
| 92 | static int neigh_blackhole(struct neighbour *neigh, struct sk_buff *skb) |
| 93 | { |
| 94 | kfree_skb(skb); |
| 95 | return -ENETDOWN; |
| 96 | } |
| 97 | |
| 98 | static void neigh_cleanup_and_release(struct neighbour *neigh) |
| 99 | { |
| 100 | trace_neigh_cleanup_and_release(neigh, 0); |
| 101 | __neigh_notify(neigh, RTM_DELNEIGH, 0, 0); |
| 102 | call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, neigh); |
| 103 | neigh_release(neigh); |
| 104 | } |
| 105 | |
| 106 | /* |
| 107 | * It is random distribution in the interval (1/2)*base...(3/2)*base. |
| 108 | * It corresponds to default IPv6 settings and is not overridable, |
| 109 | * because it is really reasonable choice. |
| 110 | */ |
| 111 | |
| 112 | unsigned long neigh_rand_reach_time(unsigned long base) |
| 113 | { |
| 114 | return base ? get_random_u32_below(base) + (base >> 1) : 0; |
| 115 | } |
| 116 | EXPORT_SYMBOL(neigh_rand_reach_time); |
| 117 | |
| 118 | static void neigh_mark_dead(struct neighbour *n) |
| 119 | { |
| 120 | n->dead = 1; |
| 121 | if (!list_empty(&n->gc_list)) { |
| 122 | list_del_init(&n->gc_list); |
| 123 | atomic_dec(&n->tbl->gc_entries); |
| 124 | } |
| 125 | if (!list_empty(&n->managed_list)) |
| 126 | list_del_init(&n->managed_list); |
| 127 | } |
| 128 | |
| 129 | static void neigh_update_gc_list(struct neighbour *n) |
| 130 | { |
| 131 | bool on_gc_list, exempt_from_gc; |
| 132 | |
| 133 | write_lock_bh(&n->tbl->lock); |
| 134 | write_lock(&n->lock); |
| 135 | if (n->dead) |
| 136 | goto out; |
| 137 | |
| 138 | /* remove from the gc list if new state is permanent or if neighbor |
| 139 | * is externally learned; otherwise entry should be on the gc list |
| 140 | */ |
| 141 | exempt_from_gc = n->nud_state & NUD_PERMANENT || |
| 142 | n->flags & NTF_EXT_LEARNED; |
| 143 | on_gc_list = !list_empty(&n->gc_list); |
| 144 | |
| 145 | if (exempt_from_gc && on_gc_list) { |
| 146 | list_del_init(&n->gc_list); |
| 147 | atomic_dec(&n->tbl->gc_entries); |
| 148 | } else if (!exempt_from_gc && !on_gc_list) { |
| 149 | /* add entries to the tail; cleaning removes from the front */ |
| 150 | list_add_tail(&n->gc_list, &n->tbl->gc_list); |
| 151 | atomic_inc(&n->tbl->gc_entries); |
| 152 | } |
| 153 | out: |
| 154 | write_unlock(&n->lock); |
| 155 | write_unlock_bh(&n->tbl->lock); |
| 156 | } |
| 157 | |
| 158 | static void neigh_update_managed_list(struct neighbour *n) |
| 159 | { |
| 160 | bool on_managed_list, add_to_managed; |
| 161 | |
| 162 | write_lock_bh(&n->tbl->lock); |
| 163 | write_lock(&n->lock); |
| 164 | if (n->dead) |
| 165 | goto out; |
| 166 | |
| 167 | add_to_managed = n->flags & NTF_MANAGED; |
| 168 | on_managed_list = !list_empty(&n->managed_list); |
| 169 | |
| 170 | if (!add_to_managed && on_managed_list) |
| 171 | list_del_init(&n->managed_list); |
| 172 | else if (add_to_managed && !on_managed_list) |
| 173 | list_add_tail(&n->managed_list, &n->tbl->managed_list); |
| 174 | out: |
| 175 | write_unlock(&n->lock); |
| 176 | write_unlock_bh(&n->tbl->lock); |
| 177 | } |
| 178 | |
| 179 | static void neigh_update_flags(struct neighbour *neigh, u32 flags, int *notify, |
| 180 | bool *gc_update, bool *managed_update) |
| 181 | { |
| 182 | u32 ndm_flags, old_flags = neigh->flags; |
| 183 | |
| 184 | if (!(flags & NEIGH_UPDATE_F_ADMIN)) |
| 185 | return; |
| 186 | |
| 187 | ndm_flags = (flags & NEIGH_UPDATE_F_EXT_LEARNED) ? NTF_EXT_LEARNED : 0; |
| 188 | ndm_flags |= (flags & NEIGH_UPDATE_F_MANAGED) ? NTF_MANAGED : 0; |
| 189 | |
| 190 | if ((old_flags ^ ndm_flags) & NTF_EXT_LEARNED) { |
| 191 | if (ndm_flags & NTF_EXT_LEARNED) |
| 192 | neigh->flags |= NTF_EXT_LEARNED; |
| 193 | else |
| 194 | neigh->flags &= ~NTF_EXT_LEARNED; |
| 195 | *notify = 1; |
| 196 | *gc_update = true; |
| 197 | } |
| 198 | if ((old_flags ^ ndm_flags) & NTF_MANAGED) { |
| 199 | if (ndm_flags & NTF_MANAGED) |
| 200 | neigh->flags |= NTF_MANAGED; |
| 201 | else |
| 202 | neigh->flags &= ~NTF_MANAGED; |
| 203 | *notify = 1; |
| 204 | *managed_update = true; |
| 205 | } |
| 206 | } |
| 207 | |
| 208 | static bool neigh_del(struct neighbour *n, struct neighbour __rcu **np, |
| 209 | struct neigh_table *tbl) |
| 210 | { |
| 211 | bool retval = false; |
| 212 | |
| 213 | write_lock(&n->lock); |
| 214 | if (refcount_read(&n->refcnt) == 1) { |
| 215 | struct neighbour *neigh; |
| 216 | |
| 217 | neigh = rcu_dereference_protected(n->next, |
| 218 | lockdep_is_held(&tbl->lock)); |
| 219 | rcu_assign_pointer(*np, neigh); |
| 220 | neigh_mark_dead(n); |
| 221 | retval = true; |
| 222 | } |
| 223 | write_unlock(&n->lock); |
| 224 | if (retval) |
| 225 | neigh_cleanup_and_release(n); |
| 226 | return retval; |
| 227 | } |
| 228 | |
| 229 | bool neigh_remove_one(struct neighbour *ndel, struct neigh_table *tbl) |
| 230 | { |
| 231 | struct neigh_hash_table *nht; |
| 232 | void *pkey = ndel->primary_key; |
| 233 | u32 hash_val; |
| 234 | struct neighbour *n; |
| 235 | struct neighbour __rcu **np; |
| 236 | |
| 237 | nht = rcu_dereference_protected(tbl->nht, |
| 238 | lockdep_is_held(&tbl->lock)); |
| 239 | hash_val = tbl->hash(pkey, ndel->dev, nht->hash_rnd); |
| 240 | hash_val = hash_val >> (32 - nht->hash_shift); |
| 241 | |
| 242 | np = &nht->hash_buckets[hash_val]; |
| 243 | while ((n = rcu_dereference_protected(*np, |
| 244 | lockdep_is_held(&tbl->lock)))) { |
| 245 | if (n == ndel) |
| 246 | return neigh_del(n, np, tbl); |
| 247 | np = &n->next; |
| 248 | } |
| 249 | return false; |
| 250 | } |
| 251 | |
| 252 | static int neigh_forced_gc(struct neigh_table *tbl) |
| 253 | { |
| 254 | int max_clean = atomic_read(&tbl->gc_entries) - |
| 255 | READ_ONCE(tbl->gc_thresh2); |
| 256 | u64 tmax = ktime_get_ns() + NSEC_PER_MSEC; |
| 257 | unsigned long tref = jiffies - 5 * HZ; |
| 258 | struct neighbour *n, *tmp; |
| 259 | int shrunk = 0; |
| 260 | int loop = 0; |
| 261 | |
| 262 | NEIGH_CACHE_STAT_INC(tbl, forced_gc_runs); |
| 263 | |
| 264 | write_lock_bh(&tbl->lock); |
| 265 | |
| 266 | list_for_each_entry_safe(n, tmp, &tbl->gc_list, gc_list) { |
| 267 | if (refcount_read(&n->refcnt) == 1) { |
| 268 | bool remove = false; |
| 269 | |
| 270 | write_lock(&n->lock); |
| 271 | if ((n->nud_state == NUD_FAILED) || |
| 272 | (n->nud_state == NUD_NOARP) || |
| 273 | (tbl->is_multicast && |
| 274 | tbl->is_multicast(n->primary_key)) || |
| 275 | !time_in_range(n->updated, tref, jiffies)) |
| 276 | remove = true; |
| 277 | write_unlock(&n->lock); |
| 278 | |
| 279 | if (remove && neigh_remove_one(n, tbl)) |
| 280 | shrunk++; |
| 281 | if (shrunk >= max_clean) |
| 282 | break; |
| 283 | if (++loop == 16) { |
| 284 | if (ktime_get_ns() > tmax) |
| 285 | goto unlock; |
| 286 | loop = 0; |
| 287 | } |
| 288 | } |
| 289 | } |
| 290 | |
| 291 | WRITE_ONCE(tbl->last_flush, jiffies); |
| 292 | unlock: |
| 293 | write_unlock_bh(&tbl->lock); |
| 294 | |
| 295 | return shrunk; |
| 296 | } |
| 297 | |
| 298 | static void neigh_add_timer(struct neighbour *n, unsigned long when) |
| 299 | { |
| 300 | /* Use safe distance from the jiffies - LONG_MAX point while timer |
| 301 | * is running in DELAY/PROBE state but still show to user space |
| 302 | * large times in the past. |
| 303 | */ |
| 304 | unsigned long mint = jiffies - (LONG_MAX - 86400 * HZ); |
| 305 | |
| 306 | neigh_hold(n); |
| 307 | if (!time_in_range(n->confirmed, mint, jiffies)) |
| 308 | n->confirmed = mint; |
| 309 | if (time_before(n->used, n->confirmed)) |
| 310 | n->used = n->confirmed; |
| 311 | if (unlikely(mod_timer(&n->timer, when))) { |
| 312 | printk("NEIGH: BUG, double timer add, state is %x\n", |
| 313 | n->nud_state); |
| 314 | dump_stack(); |
| 315 | } |
| 316 | } |
| 317 | |
| 318 | static int neigh_del_timer(struct neighbour *n) |
| 319 | { |
| 320 | if ((n->nud_state & NUD_IN_TIMER) && |
| 321 | del_timer(&n->timer)) { |
| 322 | neigh_release(n); |
| 323 | return 1; |
| 324 | } |
| 325 | return 0; |
| 326 | } |
| 327 | |
| 328 | static struct neigh_parms *neigh_get_dev_parms_rcu(struct net_device *dev, |
| 329 | int family) |
| 330 | { |
| 331 | switch (family) { |
| 332 | case AF_INET: |
| 333 | return __in_dev_arp_parms_get_rcu(dev); |
| 334 | case AF_INET6: |
| 335 | return __in6_dev_nd_parms_get_rcu(dev); |
| 336 | } |
| 337 | return NULL; |
| 338 | } |
| 339 | |
| 340 | static void neigh_parms_qlen_dec(struct net_device *dev, int family) |
| 341 | { |
| 342 | struct neigh_parms *p; |
| 343 | |
| 344 | rcu_read_lock(); |
| 345 | p = neigh_get_dev_parms_rcu(dev, family); |
| 346 | if (p) |
| 347 | p->qlen--; |
| 348 | rcu_read_unlock(); |
| 349 | } |
| 350 | |
| 351 | static void pneigh_queue_purge(struct sk_buff_head *list, struct net *net, |
| 352 | int family) |
| 353 | { |
| 354 | struct sk_buff_head tmp; |
| 355 | unsigned long flags; |
| 356 | struct sk_buff *skb; |
| 357 | |
| 358 | skb_queue_head_init(&tmp); |
| 359 | spin_lock_irqsave(&list->lock, flags); |
| 360 | skb = skb_peek(list); |
| 361 | while (skb != NULL) { |
| 362 | struct sk_buff *skb_next = skb_peek_next(skb, list); |
| 363 | struct net_device *dev = skb->dev; |
| 364 | |
| 365 | if (net == NULL || net_eq(dev_net(dev), net)) { |
| 366 | neigh_parms_qlen_dec(dev, family); |
| 367 | __skb_unlink(skb, list); |
| 368 | __skb_queue_tail(&tmp, skb); |
| 369 | } |
| 370 | skb = skb_next; |
| 371 | } |
| 372 | spin_unlock_irqrestore(&list->lock, flags); |
| 373 | |
| 374 | while ((skb = __skb_dequeue(&tmp))) { |
| 375 | dev_put(skb->dev); |
| 376 | kfree_skb(skb); |
| 377 | } |
| 378 | } |
| 379 | |
| 380 | static void neigh_flush_dev(struct neigh_table *tbl, struct net_device *dev, |
| 381 | bool skip_perm) |
| 382 | { |
| 383 | int i; |
| 384 | struct neigh_hash_table *nht; |
| 385 | |
| 386 | nht = rcu_dereference_protected(tbl->nht, |
| 387 | lockdep_is_held(&tbl->lock)); |
| 388 | |
| 389 | for (i = 0; i < (1 << nht->hash_shift); i++) { |
| 390 | struct neighbour *n; |
| 391 | struct neighbour __rcu **np = &nht->hash_buckets[i]; |
| 392 | |
| 393 | while ((n = rcu_dereference_protected(*np, |
| 394 | lockdep_is_held(&tbl->lock))) != NULL) { |
| 395 | if (dev && n->dev != dev) { |
| 396 | np = &n->next; |
| 397 | continue; |
| 398 | } |
| 399 | if (skip_perm && n->nud_state & NUD_PERMANENT) { |
| 400 | np = &n->next; |
| 401 | continue; |
| 402 | } |
| 403 | rcu_assign_pointer(*np, |
| 404 | rcu_dereference_protected(n->next, |
| 405 | lockdep_is_held(&tbl->lock))); |
| 406 | write_lock(&n->lock); |
| 407 | neigh_del_timer(n); |
| 408 | neigh_mark_dead(n); |
| 409 | if (refcount_read(&n->refcnt) != 1) { |
| 410 | /* The most unpleasant situation. |
| 411 | We must destroy neighbour entry, |
| 412 | but someone still uses it. |
| 413 | |
| 414 | The destroy will be delayed until |
| 415 | the last user releases us, but |
| 416 | we must kill timers etc. and move |
| 417 | it to safe state. |
| 418 | */ |
| 419 | __skb_queue_purge(&n->arp_queue); |
| 420 | n->arp_queue_len_bytes = 0; |
| 421 | WRITE_ONCE(n->output, neigh_blackhole); |
| 422 | if (n->nud_state & NUD_VALID) |
| 423 | n->nud_state = NUD_NOARP; |
| 424 | else |
| 425 | n->nud_state = NUD_NONE; |
| 426 | neigh_dbg(2, "neigh %p is stray\n", n); |
| 427 | } |
| 428 | write_unlock(&n->lock); |
| 429 | neigh_cleanup_and_release(n); |
| 430 | } |
| 431 | } |
| 432 | } |
| 433 | |
| 434 | void neigh_changeaddr(struct neigh_table *tbl, struct net_device *dev) |
| 435 | { |
| 436 | write_lock_bh(&tbl->lock); |
| 437 | neigh_flush_dev(tbl, dev, false); |
| 438 | write_unlock_bh(&tbl->lock); |
| 439 | } |
| 440 | EXPORT_SYMBOL(neigh_changeaddr); |
| 441 | |
| 442 | static int __neigh_ifdown(struct neigh_table *tbl, struct net_device *dev, |
| 443 | bool skip_perm) |
| 444 | { |
| 445 | write_lock_bh(&tbl->lock); |
| 446 | neigh_flush_dev(tbl, dev, skip_perm); |
| 447 | pneigh_ifdown_and_unlock(tbl, dev); |
| 448 | pneigh_queue_purge(&tbl->proxy_queue, dev ? dev_net(dev) : NULL, |
| 449 | tbl->family); |
| 450 | if (skb_queue_empty_lockless(&tbl->proxy_queue)) |
| 451 | del_timer_sync(&tbl->proxy_timer); |
| 452 | return 0; |
| 453 | } |
| 454 | |
| 455 | int neigh_carrier_down(struct neigh_table *tbl, struct net_device *dev) |
| 456 | { |
| 457 | __neigh_ifdown(tbl, dev, true); |
| 458 | return 0; |
| 459 | } |
| 460 | EXPORT_SYMBOL(neigh_carrier_down); |
| 461 | |
| 462 | int neigh_ifdown(struct neigh_table *tbl, struct net_device *dev) |
| 463 | { |
| 464 | __neigh_ifdown(tbl, dev, false); |
| 465 | return 0; |
| 466 | } |
| 467 | EXPORT_SYMBOL(neigh_ifdown); |
| 468 | |
| 469 | static struct neighbour *neigh_alloc(struct neigh_table *tbl, |
| 470 | struct net_device *dev, |
| 471 | u32 flags, bool exempt_from_gc) |
| 472 | { |
| 473 | struct neighbour *n = NULL; |
| 474 | unsigned long now = jiffies; |
| 475 | int entries, gc_thresh3; |
| 476 | |
| 477 | if (exempt_from_gc) |
| 478 | goto do_alloc; |
| 479 | |
| 480 | entries = atomic_inc_return(&tbl->gc_entries) - 1; |
| 481 | gc_thresh3 = READ_ONCE(tbl->gc_thresh3); |
| 482 | if (entries >= gc_thresh3 || |
| 483 | (entries >= READ_ONCE(tbl->gc_thresh2) && |
| 484 | time_after(now, READ_ONCE(tbl->last_flush) + 5 * HZ))) { |
| 485 | if (!neigh_forced_gc(tbl) && entries >= gc_thresh3) { |
| 486 | net_info_ratelimited("%s: neighbor table overflow!\n", |
| 487 | tbl->id); |
| 488 | NEIGH_CACHE_STAT_INC(tbl, table_fulls); |
| 489 | goto out_entries; |
| 490 | } |
| 491 | } |
| 492 | |
| 493 | do_alloc: |
| 494 | n = kzalloc(tbl->entry_size + dev->neigh_priv_len, GFP_ATOMIC); |
| 495 | if (!n) |
| 496 | goto out_entries; |
| 497 | |
| 498 | __skb_queue_head_init(&n->arp_queue); |
| 499 | rwlock_init(&n->lock); |
| 500 | seqlock_init(&n->ha_lock); |
| 501 | n->updated = n->used = now; |
| 502 | n->nud_state = NUD_NONE; |
| 503 | n->output = neigh_blackhole; |
| 504 | n->flags = flags; |
| 505 | seqlock_init(&n->hh.hh_lock); |
| 506 | n->parms = neigh_parms_clone(&tbl->parms); |
| 507 | timer_setup(&n->timer, neigh_timer_handler, 0); |
| 508 | |
| 509 | NEIGH_CACHE_STAT_INC(tbl, allocs); |
| 510 | n->tbl = tbl; |
| 511 | refcount_set(&n->refcnt, 1); |
| 512 | n->dead = 1; |
| 513 | INIT_LIST_HEAD(&n->gc_list); |
| 514 | INIT_LIST_HEAD(&n->managed_list); |
| 515 | |
| 516 | atomic_inc(&tbl->entries); |
| 517 | out: |
| 518 | return n; |
| 519 | |
| 520 | out_entries: |
| 521 | if (!exempt_from_gc) |
| 522 | atomic_dec(&tbl->gc_entries); |
| 523 | goto out; |
| 524 | } |
| 525 | |
| 526 | static void neigh_get_hash_rnd(u32 *x) |
| 527 | { |
| 528 | *x = get_random_u32() | 1; |
| 529 | } |
| 530 | |
| 531 | static struct neigh_hash_table *neigh_hash_alloc(unsigned int shift) |
| 532 | { |
| 533 | size_t size = (1 << shift) * sizeof(struct neighbour *); |
| 534 | struct neigh_hash_table *ret; |
| 535 | struct neighbour __rcu **buckets; |
| 536 | int i; |
| 537 | |
| 538 | ret = kmalloc(sizeof(*ret), GFP_ATOMIC); |
| 539 | if (!ret) |
| 540 | return NULL; |
| 541 | if (size <= PAGE_SIZE) { |
| 542 | buckets = kzalloc(size, GFP_ATOMIC); |
| 543 | } else { |
| 544 | buckets = (struct neighbour __rcu **) |
| 545 | __get_free_pages(GFP_ATOMIC | __GFP_ZERO, |
| 546 | get_order(size)); |
| 547 | kmemleak_alloc(buckets, size, 1, GFP_ATOMIC); |
| 548 | } |
| 549 | if (!buckets) { |
| 550 | kfree(ret); |
| 551 | return NULL; |
| 552 | } |
| 553 | ret->hash_buckets = buckets; |
| 554 | ret->hash_shift = shift; |
| 555 | for (i = 0; i < NEIGH_NUM_HASH_RND; i++) |
| 556 | neigh_get_hash_rnd(&ret->hash_rnd[i]); |
| 557 | return ret; |
| 558 | } |
| 559 | |
| 560 | static void neigh_hash_free_rcu(struct rcu_head *head) |
| 561 | { |
| 562 | struct neigh_hash_table *nht = container_of(head, |
| 563 | struct neigh_hash_table, |
| 564 | rcu); |
| 565 | size_t size = (1 << nht->hash_shift) * sizeof(struct neighbour *); |
| 566 | struct neighbour __rcu **buckets = nht->hash_buckets; |
| 567 | |
| 568 | if (size <= PAGE_SIZE) { |
| 569 | kfree(buckets); |
| 570 | } else { |
| 571 | kmemleak_free(buckets); |
| 572 | free_pages((unsigned long)buckets, get_order(size)); |
| 573 | } |
| 574 | kfree(nht); |
| 575 | } |
| 576 | |
| 577 | static struct neigh_hash_table *neigh_hash_grow(struct neigh_table *tbl, |
| 578 | unsigned long new_shift) |
| 579 | { |
| 580 | unsigned int i, hash; |
| 581 | struct neigh_hash_table *new_nht, *old_nht; |
| 582 | |
| 583 | NEIGH_CACHE_STAT_INC(tbl, hash_grows); |
| 584 | |
| 585 | old_nht = rcu_dereference_protected(tbl->nht, |
| 586 | lockdep_is_held(&tbl->lock)); |
| 587 | new_nht = neigh_hash_alloc(new_shift); |
| 588 | if (!new_nht) |
| 589 | return old_nht; |
| 590 | |
| 591 | for (i = 0; i < (1 << old_nht->hash_shift); i++) { |
| 592 | struct neighbour *n, *next; |
| 593 | |
| 594 | for (n = rcu_dereference_protected(old_nht->hash_buckets[i], |
| 595 | lockdep_is_held(&tbl->lock)); |
| 596 | n != NULL; |
| 597 | n = next) { |
| 598 | hash = tbl->hash(n->primary_key, n->dev, |
| 599 | new_nht->hash_rnd); |
| 600 | |
| 601 | hash >>= (32 - new_nht->hash_shift); |
| 602 | next = rcu_dereference_protected(n->next, |
| 603 | lockdep_is_held(&tbl->lock)); |
| 604 | |
| 605 | rcu_assign_pointer(n->next, |
| 606 | rcu_dereference_protected( |
| 607 | new_nht->hash_buckets[hash], |
| 608 | lockdep_is_held(&tbl->lock))); |
| 609 | rcu_assign_pointer(new_nht->hash_buckets[hash], n); |
| 610 | } |
| 611 | } |
| 612 | |
| 613 | rcu_assign_pointer(tbl->nht, new_nht); |
| 614 | call_rcu(&old_nht->rcu, neigh_hash_free_rcu); |
| 615 | return new_nht; |
| 616 | } |
| 617 | |
| 618 | struct neighbour *neigh_lookup(struct neigh_table *tbl, const void *pkey, |
| 619 | struct net_device *dev) |
| 620 | { |
| 621 | struct neighbour *n; |
| 622 | |
| 623 | NEIGH_CACHE_STAT_INC(tbl, lookups); |
| 624 | |
| 625 | rcu_read_lock(); |
| 626 | n = __neigh_lookup_noref(tbl, pkey, dev); |
| 627 | if (n) { |
| 628 | if (!refcount_inc_not_zero(&n->refcnt)) |
| 629 | n = NULL; |
| 630 | NEIGH_CACHE_STAT_INC(tbl, hits); |
| 631 | } |
| 632 | |
| 633 | rcu_read_unlock(); |
| 634 | return n; |
| 635 | } |
| 636 | EXPORT_SYMBOL(neigh_lookup); |
| 637 | |
| 638 | static struct neighbour * |
| 639 | ___neigh_create(struct neigh_table *tbl, const void *pkey, |
| 640 | struct net_device *dev, u32 flags, |
| 641 | bool exempt_from_gc, bool want_ref) |
| 642 | { |
| 643 | u32 hash_val, key_len = tbl->key_len; |
| 644 | struct neighbour *n1, *rc, *n; |
| 645 | struct neigh_hash_table *nht; |
| 646 | int error; |
| 647 | |
| 648 | n = neigh_alloc(tbl, dev, flags, exempt_from_gc); |
| 649 | trace_neigh_create(tbl, dev, pkey, n, exempt_from_gc); |
| 650 | if (!n) { |
| 651 | rc = ERR_PTR(-ENOBUFS); |
| 652 | goto out; |
| 653 | } |
| 654 | |
| 655 | memcpy(n->primary_key, pkey, key_len); |
| 656 | n->dev = dev; |
| 657 | netdev_hold(dev, &n->dev_tracker, GFP_ATOMIC); |
| 658 | |
| 659 | /* Protocol specific setup. */ |
| 660 | if (tbl->constructor && (error = tbl->constructor(n)) < 0) { |
| 661 | rc = ERR_PTR(error); |
| 662 | goto out_neigh_release; |
| 663 | } |
| 664 | |
| 665 | if (dev->netdev_ops->ndo_neigh_construct) { |
| 666 | error = dev->netdev_ops->ndo_neigh_construct(dev, n); |
| 667 | if (error < 0) { |
| 668 | rc = ERR_PTR(error); |
| 669 | goto out_neigh_release; |
| 670 | } |
| 671 | } |
| 672 | |
| 673 | /* Device specific setup. */ |
| 674 | if (n->parms->neigh_setup && |
| 675 | (error = n->parms->neigh_setup(n)) < 0) { |
| 676 | rc = ERR_PTR(error); |
| 677 | goto out_neigh_release; |
| 678 | } |
| 679 | |
| 680 | n->confirmed = jiffies - (NEIGH_VAR(n->parms, BASE_REACHABLE_TIME) << 1); |
| 681 | |
| 682 | write_lock_bh(&tbl->lock); |
| 683 | nht = rcu_dereference_protected(tbl->nht, |
| 684 | lockdep_is_held(&tbl->lock)); |
| 685 | |
| 686 | if (atomic_read(&tbl->entries) > (1 << nht->hash_shift)) |
| 687 | nht = neigh_hash_grow(tbl, nht->hash_shift + 1); |
| 688 | |
| 689 | hash_val = tbl->hash(n->primary_key, dev, nht->hash_rnd) >> (32 - nht->hash_shift); |
| 690 | |
| 691 | if (n->parms->dead) { |
| 692 | rc = ERR_PTR(-EINVAL); |
| 693 | goto out_tbl_unlock; |
| 694 | } |
| 695 | |
| 696 | for (n1 = rcu_dereference_protected(nht->hash_buckets[hash_val], |
| 697 | lockdep_is_held(&tbl->lock)); |
| 698 | n1 != NULL; |
| 699 | n1 = rcu_dereference_protected(n1->next, |
| 700 | lockdep_is_held(&tbl->lock))) { |
| 701 | if (dev == n1->dev && !memcmp(n1->primary_key, n->primary_key, key_len)) { |
| 702 | if (want_ref) |
| 703 | neigh_hold(n1); |
| 704 | rc = n1; |
| 705 | goto out_tbl_unlock; |
| 706 | } |
| 707 | } |
| 708 | |
| 709 | n->dead = 0; |
| 710 | if (!exempt_from_gc) |
| 711 | list_add_tail(&n->gc_list, &n->tbl->gc_list); |
| 712 | if (n->flags & NTF_MANAGED) |
| 713 | list_add_tail(&n->managed_list, &n->tbl->managed_list); |
| 714 | if (want_ref) |
| 715 | neigh_hold(n); |
| 716 | rcu_assign_pointer(n->next, |
| 717 | rcu_dereference_protected(nht->hash_buckets[hash_val], |
| 718 | lockdep_is_held(&tbl->lock))); |
| 719 | rcu_assign_pointer(nht->hash_buckets[hash_val], n); |
| 720 | write_unlock_bh(&tbl->lock); |
| 721 | neigh_dbg(2, "neigh %p is created\n", n); |
| 722 | rc = n; |
| 723 | out: |
| 724 | return rc; |
| 725 | out_tbl_unlock: |
| 726 | write_unlock_bh(&tbl->lock); |
| 727 | out_neigh_release: |
| 728 | if (!exempt_from_gc) |
| 729 | atomic_dec(&tbl->gc_entries); |
| 730 | neigh_release(n); |
| 731 | goto out; |
| 732 | } |
| 733 | |
| 734 | struct neighbour *__neigh_create(struct neigh_table *tbl, const void *pkey, |
| 735 | struct net_device *dev, bool want_ref) |
| 736 | { |
| 737 | bool exempt_from_gc = !!(dev->flags & IFF_LOOPBACK); |
| 738 | |
| 739 | return ___neigh_create(tbl, pkey, dev, 0, exempt_from_gc, want_ref); |
| 740 | } |
| 741 | EXPORT_SYMBOL(__neigh_create); |
| 742 | |
| 743 | static u32 pneigh_hash(const void *pkey, unsigned int key_len) |
| 744 | { |
| 745 | u32 hash_val = *(u32 *)(pkey + key_len - 4); |
| 746 | hash_val ^= (hash_val >> 16); |
| 747 | hash_val ^= hash_val >> 8; |
| 748 | hash_val ^= hash_val >> 4; |
| 749 | hash_val &= PNEIGH_HASHMASK; |
| 750 | return hash_val; |
| 751 | } |
| 752 | |
| 753 | static struct pneigh_entry *__pneigh_lookup_1(struct pneigh_entry *n, |
| 754 | struct net *net, |
| 755 | const void *pkey, |
| 756 | unsigned int key_len, |
| 757 | struct net_device *dev) |
| 758 | { |
| 759 | while (n) { |
| 760 | if (!memcmp(n->key, pkey, key_len) && |
| 761 | net_eq(pneigh_net(n), net) && |
| 762 | (n->dev == dev || !n->dev)) |
| 763 | return n; |
| 764 | n = n->next; |
| 765 | } |
| 766 | return NULL; |
| 767 | } |
| 768 | |
| 769 | struct pneigh_entry *__pneigh_lookup(struct neigh_table *tbl, |
| 770 | struct net *net, const void *pkey, struct net_device *dev) |
| 771 | { |
| 772 | unsigned int key_len = tbl->key_len; |
| 773 | u32 hash_val = pneigh_hash(pkey, key_len); |
| 774 | |
| 775 | return __pneigh_lookup_1(tbl->phash_buckets[hash_val], |
| 776 | net, pkey, key_len, dev); |
| 777 | } |
| 778 | EXPORT_SYMBOL_GPL(__pneigh_lookup); |
| 779 | |
| 780 | struct pneigh_entry * pneigh_lookup(struct neigh_table *tbl, |
| 781 | struct net *net, const void *pkey, |
| 782 | struct net_device *dev, int creat) |
| 783 | { |
| 784 | struct pneigh_entry *n; |
| 785 | unsigned int key_len = tbl->key_len; |
| 786 | u32 hash_val = pneigh_hash(pkey, key_len); |
| 787 | |
| 788 | read_lock_bh(&tbl->lock); |
| 789 | n = __pneigh_lookup_1(tbl->phash_buckets[hash_val], |
| 790 | net, pkey, key_len, dev); |
| 791 | read_unlock_bh(&tbl->lock); |
| 792 | |
| 793 | if (n || !creat) |
| 794 | goto out; |
| 795 | |
| 796 | ASSERT_RTNL(); |
| 797 | |
| 798 | n = kzalloc(sizeof(*n) + key_len, GFP_KERNEL); |
| 799 | if (!n) |
| 800 | goto out; |
| 801 | |
| 802 | write_pnet(&n->net, net); |
| 803 | memcpy(n->key, pkey, key_len); |
| 804 | n->dev = dev; |
| 805 | netdev_hold(dev, &n->dev_tracker, GFP_KERNEL); |
| 806 | |
| 807 | if (tbl->pconstructor && tbl->pconstructor(n)) { |
| 808 | netdev_put(dev, &n->dev_tracker); |
| 809 | kfree(n); |
| 810 | n = NULL; |
| 811 | goto out; |
| 812 | } |
| 813 | |
| 814 | write_lock_bh(&tbl->lock); |
| 815 | n->next = tbl->phash_buckets[hash_val]; |
| 816 | tbl->phash_buckets[hash_val] = n; |
| 817 | write_unlock_bh(&tbl->lock); |
| 818 | out: |
| 819 | return n; |
| 820 | } |
| 821 | EXPORT_SYMBOL(pneigh_lookup); |
| 822 | |
| 823 | |
| 824 | int pneigh_delete(struct neigh_table *tbl, struct net *net, const void *pkey, |
| 825 | struct net_device *dev) |
| 826 | { |
| 827 | struct pneigh_entry *n, **np; |
| 828 | unsigned int key_len = tbl->key_len; |
| 829 | u32 hash_val = pneigh_hash(pkey, key_len); |
| 830 | |
| 831 | write_lock_bh(&tbl->lock); |
| 832 | for (np = &tbl->phash_buckets[hash_val]; (n = *np) != NULL; |
| 833 | np = &n->next) { |
| 834 | if (!memcmp(n->key, pkey, key_len) && n->dev == dev && |
| 835 | net_eq(pneigh_net(n), net)) { |
| 836 | *np = n->next; |
| 837 | write_unlock_bh(&tbl->lock); |
| 838 | if (tbl->pdestructor) |
| 839 | tbl->pdestructor(n); |
| 840 | netdev_put(n->dev, &n->dev_tracker); |
| 841 | kfree(n); |
| 842 | return 0; |
| 843 | } |
| 844 | } |
| 845 | write_unlock_bh(&tbl->lock); |
| 846 | return -ENOENT; |
| 847 | } |
| 848 | |
| 849 | static int pneigh_ifdown_and_unlock(struct neigh_table *tbl, |
| 850 | struct net_device *dev) |
| 851 | { |
| 852 | struct pneigh_entry *n, **np, *freelist = NULL; |
| 853 | u32 h; |
| 854 | |
| 855 | for (h = 0; h <= PNEIGH_HASHMASK; h++) { |
| 856 | np = &tbl->phash_buckets[h]; |
| 857 | while ((n = *np) != NULL) { |
| 858 | if (!dev || n->dev == dev) { |
| 859 | *np = n->next; |
| 860 | n->next = freelist; |
| 861 | freelist = n; |
| 862 | continue; |
| 863 | } |
| 864 | np = &n->next; |
| 865 | } |
| 866 | } |
| 867 | write_unlock_bh(&tbl->lock); |
| 868 | while ((n = freelist)) { |
| 869 | freelist = n->next; |
| 870 | n->next = NULL; |
| 871 | if (tbl->pdestructor) |
| 872 | tbl->pdestructor(n); |
| 873 | netdev_put(n->dev, &n->dev_tracker); |
| 874 | kfree(n); |
| 875 | } |
| 876 | return -ENOENT; |
| 877 | } |
| 878 | |
| 879 | static void neigh_parms_destroy(struct neigh_parms *parms); |
| 880 | |
| 881 | static inline void neigh_parms_put(struct neigh_parms *parms) |
| 882 | { |
| 883 | if (refcount_dec_and_test(&parms->refcnt)) |
| 884 | neigh_parms_destroy(parms); |
| 885 | } |
| 886 | |
| 887 | /* |
| 888 | * neighbour must already be out of the table; |
| 889 | * |
| 890 | */ |
| 891 | void neigh_destroy(struct neighbour *neigh) |
| 892 | { |
| 893 | struct net_device *dev = neigh->dev; |
| 894 | |
| 895 | NEIGH_CACHE_STAT_INC(neigh->tbl, destroys); |
| 896 | |
| 897 | if (!neigh->dead) { |
| 898 | pr_warn("Destroying alive neighbour %p\n", neigh); |
| 899 | dump_stack(); |
| 900 | return; |
| 901 | } |
| 902 | |
| 903 | if (neigh_del_timer(neigh)) |
| 904 | pr_warn("Impossible event\n"); |
| 905 | |
| 906 | write_lock_bh(&neigh->lock); |
| 907 | __skb_queue_purge(&neigh->arp_queue); |
| 908 | write_unlock_bh(&neigh->lock); |
| 909 | neigh->arp_queue_len_bytes = 0; |
| 910 | |
| 911 | if (dev->netdev_ops->ndo_neigh_destroy) |
| 912 | dev->netdev_ops->ndo_neigh_destroy(dev, neigh); |
| 913 | |
| 914 | netdev_put(dev, &neigh->dev_tracker); |
| 915 | neigh_parms_put(neigh->parms); |
| 916 | |
| 917 | neigh_dbg(2, "neigh %p is destroyed\n", neigh); |
| 918 | |
| 919 | atomic_dec(&neigh->tbl->entries); |
| 920 | kfree_rcu(neigh, rcu); |
| 921 | } |
| 922 | EXPORT_SYMBOL(neigh_destroy); |
| 923 | |
| 924 | /* Neighbour state is suspicious; |
| 925 | disable fast path. |
| 926 | |
| 927 | Called with write_locked neigh. |
| 928 | */ |
| 929 | static void neigh_suspect(struct neighbour *neigh) |
| 930 | { |
| 931 | neigh_dbg(2, "neigh %p is suspected\n", neigh); |
| 932 | |
| 933 | WRITE_ONCE(neigh->output, neigh->ops->output); |
| 934 | } |
| 935 | |
| 936 | /* Neighbour state is OK; |
| 937 | enable fast path. |
| 938 | |
| 939 | Called with write_locked neigh. |
| 940 | */ |
| 941 | static void neigh_connect(struct neighbour *neigh) |
| 942 | { |
| 943 | neigh_dbg(2, "neigh %p is connected\n", neigh); |
| 944 | |
| 945 | WRITE_ONCE(neigh->output, neigh->ops->connected_output); |
| 946 | } |
| 947 | |
| 948 | static void neigh_periodic_work(struct work_struct *work) |
| 949 | { |
| 950 | struct neigh_table *tbl = container_of(work, struct neigh_table, gc_work.work); |
| 951 | struct neighbour *n; |
| 952 | struct neighbour __rcu **np; |
| 953 | unsigned int i; |
| 954 | struct neigh_hash_table *nht; |
| 955 | |
| 956 | NEIGH_CACHE_STAT_INC(tbl, periodic_gc_runs); |
| 957 | |
| 958 | write_lock_bh(&tbl->lock); |
| 959 | nht = rcu_dereference_protected(tbl->nht, |
| 960 | lockdep_is_held(&tbl->lock)); |
| 961 | |
| 962 | /* |
| 963 | * periodically recompute ReachableTime from random function |
| 964 | */ |
| 965 | |
| 966 | if (time_after(jiffies, tbl->last_rand + 300 * HZ)) { |
| 967 | struct neigh_parms *p; |
| 968 | |
| 969 | WRITE_ONCE(tbl->last_rand, jiffies); |
| 970 | list_for_each_entry(p, &tbl->parms_list, list) |
| 971 | p->reachable_time = |
| 972 | neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME)); |
| 973 | } |
| 974 | |
| 975 | if (atomic_read(&tbl->entries) < READ_ONCE(tbl->gc_thresh1)) |
| 976 | goto out; |
| 977 | |
| 978 | for (i = 0 ; i < (1 << nht->hash_shift); i++) { |
| 979 | np = &nht->hash_buckets[i]; |
| 980 | |
| 981 | while ((n = rcu_dereference_protected(*np, |
| 982 | lockdep_is_held(&tbl->lock))) != NULL) { |
| 983 | unsigned int state; |
| 984 | |
| 985 | write_lock(&n->lock); |
| 986 | |
| 987 | state = n->nud_state; |
| 988 | if ((state & (NUD_PERMANENT | NUD_IN_TIMER)) || |
| 989 | (n->flags & NTF_EXT_LEARNED)) { |
| 990 | write_unlock(&n->lock); |
| 991 | goto next_elt; |
| 992 | } |
| 993 | |
| 994 | if (time_before(n->used, n->confirmed) && |
| 995 | time_is_before_eq_jiffies(n->confirmed)) |
| 996 | n->used = n->confirmed; |
| 997 | |
| 998 | if (refcount_read(&n->refcnt) == 1 && |
| 999 | (state == NUD_FAILED || |
| 1000 | !time_in_range_open(jiffies, n->used, |
| 1001 | n->used + NEIGH_VAR(n->parms, GC_STALETIME)))) { |
| 1002 | rcu_assign_pointer(*np, |
| 1003 | rcu_dereference_protected(n->next, |
| 1004 | lockdep_is_held(&tbl->lock))); |
| 1005 | neigh_mark_dead(n); |
| 1006 | write_unlock(&n->lock); |
| 1007 | neigh_cleanup_and_release(n); |
| 1008 | continue; |
| 1009 | } |
| 1010 | write_unlock(&n->lock); |
| 1011 | |
| 1012 | next_elt: |
| 1013 | np = &n->next; |
| 1014 | } |
| 1015 | /* |
| 1016 | * It's fine to release lock here, even if hash table |
| 1017 | * grows while we are preempted. |
| 1018 | */ |
| 1019 | write_unlock_bh(&tbl->lock); |
| 1020 | cond_resched(); |
| 1021 | write_lock_bh(&tbl->lock); |
| 1022 | nht = rcu_dereference_protected(tbl->nht, |
| 1023 | lockdep_is_held(&tbl->lock)); |
| 1024 | } |
| 1025 | out: |
| 1026 | /* Cycle through all hash buckets every BASE_REACHABLE_TIME/2 ticks. |
| 1027 | * ARP entry timeouts range from 1/2 BASE_REACHABLE_TIME to 3/2 |
| 1028 | * BASE_REACHABLE_TIME. |
| 1029 | */ |
| 1030 | queue_delayed_work(system_power_efficient_wq, &tbl->gc_work, |
| 1031 | NEIGH_VAR(&tbl->parms, BASE_REACHABLE_TIME) >> 1); |
| 1032 | write_unlock_bh(&tbl->lock); |
| 1033 | } |
| 1034 | |
| 1035 | static __inline__ int neigh_max_probes(struct neighbour *n) |
| 1036 | { |
| 1037 | struct neigh_parms *p = n->parms; |
| 1038 | return NEIGH_VAR(p, UCAST_PROBES) + NEIGH_VAR(p, APP_PROBES) + |
| 1039 | (n->nud_state & NUD_PROBE ? NEIGH_VAR(p, MCAST_REPROBES) : |
| 1040 | NEIGH_VAR(p, MCAST_PROBES)); |
| 1041 | } |
| 1042 | |
| 1043 | static void neigh_invalidate(struct neighbour *neigh) |
| 1044 | __releases(neigh->lock) |
| 1045 | __acquires(neigh->lock) |
| 1046 | { |
| 1047 | struct sk_buff *skb; |
| 1048 | |
| 1049 | NEIGH_CACHE_STAT_INC(neigh->tbl, res_failed); |
| 1050 | neigh_dbg(2, "neigh %p is failed\n", neigh); |
| 1051 | neigh->updated = jiffies; |
| 1052 | |
| 1053 | /* It is very thin place. report_unreachable is very complicated |
| 1054 | routine. Particularly, it can hit the same neighbour entry! |
| 1055 | |
| 1056 | So that, we try to be accurate and avoid dead loop. --ANK |
| 1057 | */ |
| 1058 | while (neigh->nud_state == NUD_FAILED && |
| 1059 | (skb = __skb_dequeue(&neigh->arp_queue)) != NULL) { |
| 1060 | write_unlock(&neigh->lock); |
| 1061 | neigh->ops->error_report(neigh, skb); |
| 1062 | write_lock(&neigh->lock); |
| 1063 | } |
| 1064 | __skb_queue_purge(&neigh->arp_queue); |
| 1065 | neigh->arp_queue_len_bytes = 0; |
| 1066 | } |
| 1067 | |
| 1068 | static void neigh_probe(struct neighbour *neigh) |
| 1069 | __releases(neigh->lock) |
| 1070 | { |
| 1071 | struct sk_buff *skb = skb_peek_tail(&neigh->arp_queue); |
| 1072 | /* keep skb alive even if arp_queue overflows */ |
| 1073 | if (skb) |
| 1074 | skb = skb_clone(skb, GFP_ATOMIC); |
| 1075 | write_unlock(&neigh->lock); |
| 1076 | if (neigh->ops->solicit) |
| 1077 | neigh->ops->solicit(neigh, skb); |
| 1078 | atomic_inc(&neigh->probes); |
| 1079 | consume_skb(skb); |
| 1080 | } |
| 1081 | |
| 1082 | /* Called when a timer expires for a neighbour entry. */ |
| 1083 | |
| 1084 | static void neigh_timer_handler(struct timer_list *t) |
| 1085 | { |
| 1086 | unsigned long now, next; |
| 1087 | struct neighbour *neigh = from_timer(neigh, t, timer); |
| 1088 | unsigned int state; |
| 1089 | int notify = 0; |
| 1090 | |
| 1091 | write_lock(&neigh->lock); |
| 1092 | |
| 1093 | state = neigh->nud_state; |
| 1094 | now = jiffies; |
| 1095 | next = now + HZ; |
| 1096 | |
| 1097 | if (!(state & NUD_IN_TIMER)) |
| 1098 | goto out; |
| 1099 | |
| 1100 | if (state & NUD_REACHABLE) { |
| 1101 | if (time_before_eq(now, |
| 1102 | neigh->confirmed + neigh->parms->reachable_time)) { |
| 1103 | neigh_dbg(2, "neigh %p is still alive\n", neigh); |
| 1104 | next = neigh->confirmed + neigh->parms->reachable_time; |
| 1105 | } else if (time_before_eq(now, |
| 1106 | neigh->used + |
| 1107 | NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME))) { |
| 1108 | neigh_dbg(2, "neigh %p is delayed\n", neigh); |
| 1109 | WRITE_ONCE(neigh->nud_state, NUD_DELAY); |
| 1110 | neigh->updated = jiffies; |
| 1111 | neigh_suspect(neigh); |
| 1112 | next = now + NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME); |
| 1113 | } else { |
| 1114 | neigh_dbg(2, "neigh %p is suspected\n", neigh); |
| 1115 | WRITE_ONCE(neigh->nud_state, NUD_STALE); |
| 1116 | neigh->updated = jiffies; |
| 1117 | neigh_suspect(neigh); |
| 1118 | notify = 1; |
| 1119 | } |
| 1120 | } else if (state & NUD_DELAY) { |
| 1121 | if (time_before_eq(now, |
| 1122 | neigh->confirmed + |
| 1123 | NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME))) { |
| 1124 | neigh_dbg(2, "neigh %p is now reachable\n", neigh); |
| 1125 | WRITE_ONCE(neigh->nud_state, NUD_REACHABLE); |
| 1126 | neigh->updated = jiffies; |
| 1127 | neigh_connect(neigh); |
| 1128 | notify = 1; |
| 1129 | next = neigh->confirmed + neigh->parms->reachable_time; |
| 1130 | } else { |
| 1131 | neigh_dbg(2, "neigh %p is probed\n", neigh); |
| 1132 | WRITE_ONCE(neigh->nud_state, NUD_PROBE); |
| 1133 | neigh->updated = jiffies; |
| 1134 | atomic_set(&neigh->probes, 0); |
| 1135 | notify = 1; |
| 1136 | next = now + max(NEIGH_VAR(neigh->parms, RETRANS_TIME), |
| 1137 | HZ/100); |
| 1138 | } |
| 1139 | } else { |
| 1140 | /* NUD_PROBE|NUD_INCOMPLETE */ |
| 1141 | next = now + max(NEIGH_VAR(neigh->parms, RETRANS_TIME), HZ/100); |
| 1142 | } |
| 1143 | |
| 1144 | if ((neigh->nud_state & (NUD_INCOMPLETE | NUD_PROBE)) && |
| 1145 | atomic_read(&neigh->probes) >= neigh_max_probes(neigh)) { |
| 1146 | WRITE_ONCE(neigh->nud_state, NUD_FAILED); |
| 1147 | notify = 1; |
| 1148 | neigh_invalidate(neigh); |
| 1149 | goto out; |
| 1150 | } |
| 1151 | |
| 1152 | if (neigh->nud_state & NUD_IN_TIMER) { |
| 1153 | if (time_before(next, jiffies + HZ/100)) |
| 1154 | next = jiffies + HZ/100; |
| 1155 | if (!mod_timer(&neigh->timer, next)) |
| 1156 | neigh_hold(neigh); |
| 1157 | } |
| 1158 | if (neigh->nud_state & (NUD_INCOMPLETE | NUD_PROBE)) { |
| 1159 | neigh_probe(neigh); |
| 1160 | } else { |
| 1161 | out: |
| 1162 | write_unlock(&neigh->lock); |
| 1163 | } |
| 1164 | |
| 1165 | if (notify) |
| 1166 | neigh_update_notify(neigh, 0); |
| 1167 | |
| 1168 | trace_neigh_timer_handler(neigh, 0); |
| 1169 | |
| 1170 | neigh_release(neigh); |
| 1171 | } |
| 1172 | |
| 1173 | int __neigh_event_send(struct neighbour *neigh, struct sk_buff *skb, |
| 1174 | const bool immediate_ok) |
| 1175 | { |
| 1176 | int rc; |
| 1177 | bool immediate_probe = false; |
| 1178 | |
| 1179 | write_lock_bh(&neigh->lock); |
| 1180 | |
| 1181 | rc = 0; |
| 1182 | if (neigh->nud_state & (NUD_CONNECTED | NUD_DELAY | NUD_PROBE)) |
| 1183 | goto out_unlock_bh; |
| 1184 | if (neigh->dead) |
| 1185 | goto out_dead; |
| 1186 | |
| 1187 | if (!(neigh->nud_state & (NUD_STALE | NUD_INCOMPLETE))) { |
| 1188 | if (NEIGH_VAR(neigh->parms, MCAST_PROBES) + |
| 1189 | NEIGH_VAR(neigh->parms, APP_PROBES)) { |
| 1190 | unsigned long next, now = jiffies; |
| 1191 | |
| 1192 | atomic_set(&neigh->probes, |
| 1193 | NEIGH_VAR(neigh->parms, UCAST_PROBES)); |
| 1194 | neigh_del_timer(neigh); |
| 1195 | WRITE_ONCE(neigh->nud_state, NUD_INCOMPLETE); |
| 1196 | neigh->updated = now; |
| 1197 | if (!immediate_ok) { |
| 1198 | next = now + 1; |
| 1199 | } else { |
| 1200 | immediate_probe = true; |
| 1201 | next = now + max(NEIGH_VAR(neigh->parms, |
| 1202 | RETRANS_TIME), |
| 1203 | HZ / 100); |
| 1204 | } |
| 1205 | neigh_add_timer(neigh, next); |
| 1206 | } else { |
| 1207 | WRITE_ONCE(neigh->nud_state, NUD_FAILED); |
| 1208 | neigh->updated = jiffies; |
| 1209 | write_unlock_bh(&neigh->lock); |
| 1210 | |
| 1211 | kfree_skb_reason(skb, SKB_DROP_REASON_NEIGH_FAILED); |
| 1212 | return 1; |
| 1213 | } |
| 1214 | } else if (neigh->nud_state & NUD_STALE) { |
| 1215 | neigh_dbg(2, "neigh %p is delayed\n", neigh); |
| 1216 | neigh_del_timer(neigh); |
| 1217 | WRITE_ONCE(neigh->nud_state, NUD_DELAY); |
| 1218 | neigh->updated = jiffies; |
| 1219 | neigh_add_timer(neigh, jiffies + |
| 1220 | NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME)); |
| 1221 | } |
| 1222 | |
| 1223 | if (neigh->nud_state == NUD_INCOMPLETE) { |
| 1224 | if (skb) { |
| 1225 | while (neigh->arp_queue_len_bytes + skb->truesize > |
| 1226 | NEIGH_VAR(neigh->parms, QUEUE_LEN_BYTES)) { |
| 1227 | struct sk_buff *buff; |
| 1228 | |
| 1229 | buff = __skb_dequeue(&neigh->arp_queue); |
| 1230 | if (!buff) |
| 1231 | break; |
| 1232 | neigh->arp_queue_len_bytes -= buff->truesize; |
| 1233 | kfree_skb_reason(buff, SKB_DROP_REASON_NEIGH_QUEUEFULL); |
| 1234 | NEIGH_CACHE_STAT_INC(neigh->tbl, unres_discards); |
| 1235 | } |
| 1236 | skb_dst_force(skb); |
| 1237 | __skb_queue_tail(&neigh->arp_queue, skb); |
| 1238 | neigh->arp_queue_len_bytes += skb->truesize; |
| 1239 | } |
| 1240 | rc = 1; |
| 1241 | } |
| 1242 | out_unlock_bh: |
| 1243 | if (immediate_probe) |
| 1244 | neigh_probe(neigh); |
| 1245 | else |
| 1246 | write_unlock(&neigh->lock); |
| 1247 | local_bh_enable(); |
| 1248 | trace_neigh_event_send_done(neigh, rc); |
| 1249 | return rc; |
| 1250 | |
| 1251 | out_dead: |
| 1252 | if (neigh->nud_state & NUD_STALE) |
| 1253 | goto out_unlock_bh; |
| 1254 | write_unlock_bh(&neigh->lock); |
| 1255 | kfree_skb_reason(skb, SKB_DROP_REASON_NEIGH_DEAD); |
| 1256 | trace_neigh_event_send_dead(neigh, 1); |
| 1257 | return 1; |
| 1258 | } |
| 1259 | EXPORT_SYMBOL(__neigh_event_send); |
| 1260 | |
| 1261 | static void neigh_update_hhs(struct neighbour *neigh) |
| 1262 | { |
| 1263 | struct hh_cache *hh; |
| 1264 | void (*update)(struct hh_cache*, const struct net_device*, const unsigned char *) |
| 1265 | = NULL; |
| 1266 | |
| 1267 | if (neigh->dev->header_ops) |
| 1268 | update = neigh->dev->header_ops->cache_update; |
| 1269 | |
| 1270 | if (update) { |
| 1271 | hh = &neigh->hh; |
| 1272 | if (READ_ONCE(hh->hh_len)) { |
| 1273 | write_seqlock_bh(&hh->hh_lock); |
| 1274 | update(hh, neigh->dev, neigh->ha); |
| 1275 | write_sequnlock_bh(&hh->hh_lock); |
| 1276 | } |
| 1277 | } |
| 1278 | } |
| 1279 | |
| 1280 | /* Generic update routine. |
| 1281 | -- lladdr is new lladdr or NULL, if it is not supplied. |
| 1282 | -- new is new state. |
| 1283 | -- flags |
| 1284 | NEIGH_UPDATE_F_OVERRIDE allows to override existing lladdr, |
| 1285 | if it is different. |
| 1286 | NEIGH_UPDATE_F_WEAK_OVERRIDE will suspect existing "connected" |
| 1287 | lladdr instead of overriding it |
| 1288 | if it is different. |
| 1289 | NEIGH_UPDATE_F_ADMIN means that the change is administrative. |
| 1290 | NEIGH_UPDATE_F_USE means that the entry is user triggered. |
| 1291 | NEIGH_UPDATE_F_MANAGED means that the entry will be auto-refreshed. |
| 1292 | NEIGH_UPDATE_F_OVERRIDE_ISROUTER allows to override existing |
| 1293 | NTF_ROUTER flag. |
| 1294 | NEIGH_UPDATE_F_ISROUTER indicates if the neighbour is known as |
| 1295 | a router. |
| 1296 | |
| 1297 | Caller MUST hold reference count on the entry. |
| 1298 | */ |
| 1299 | static int __neigh_update(struct neighbour *neigh, const u8 *lladdr, |
| 1300 | u8 new, u32 flags, u32 nlmsg_pid, |
| 1301 | struct netlink_ext_ack *extack) |
| 1302 | { |
| 1303 | bool gc_update = false, managed_update = false; |
| 1304 | int update_isrouter = 0; |
| 1305 | struct net_device *dev; |
| 1306 | int err, notify = 0; |
| 1307 | u8 old; |
| 1308 | |
| 1309 | trace_neigh_update(neigh, lladdr, new, flags, nlmsg_pid); |
| 1310 | |
| 1311 | write_lock_bh(&neigh->lock); |
| 1312 | |
| 1313 | dev = neigh->dev; |
| 1314 | old = neigh->nud_state; |
| 1315 | err = -EPERM; |
| 1316 | |
| 1317 | if (neigh->dead) { |
| 1318 | NL_SET_ERR_MSG(extack, "Neighbor entry is now dead"); |
| 1319 | new = old; |
| 1320 | goto out; |
| 1321 | } |
| 1322 | if (!(flags & NEIGH_UPDATE_F_ADMIN) && |
| 1323 | (old & (NUD_NOARP | NUD_PERMANENT))) |
| 1324 | goto out; |
| 1325 | |
| 1326 | neigh_update_flags(neigh, flags, ¬ify, &gc_update, &managed_update); |
| 1327 | if (flags & (NEIGH_UPDATE_F_USE | NEIGH_UPDATE_F_MANAGED)) { |
| 1328 | new = old & ~NUD_PERMANENT; |
| 1329 | WRITE_ONCE(neigh->nud_state, new); |
| 1330 | err = 0; |
| 1331 | goto out; |
| 1332 | } |
| 1333 | |
| 1334 | if (!(new & NUD_VALID)) { |
| 1335 | neigh_del_timer(neigh); |
| 1336 | if (old & NUD_CONNECTED) |
| 1337 | neigh_suspect(neigh); |
| 1338 | WRITE_ONCE(neigh->nud_state, new); |
| 1339 | err = 0; |
| 1340 | notify = old & NUD_VALID; |
| 1341 | if ((old & (NUD_INCOMPLETE | NUD_PROBE)) && |
| 1342 | (new & NUD_FAILED)) { |
| 1343 | neigh_invalidate(neigh); |
| 1344 | notify = 1; |
| 1345 | } |
| 1346 | goto out; |
| 1347 | } |
| 1348 | |
| 1349 | /* Compare new lladdr with cached one */ |
| 1350 | if (!dev->addr_len) { |
| 1351 | /* First case: device needs no address. */ |
| 1352 | lladdr = neigh->ha; |
| 1353 | } else if (lladdr) { |
| 1354 | /* The second case: if something is already cached |
| 1355 | and a new address is proposed: |
| 1356 | - compare new & old |
| 1357 | - if they are different, check override flag |
| 1358 | */ |
| 1359 | if ((old & NUD_VALID) && |
| 1360 | !memcmp(lladdr, neigh->ha, dev->addr_len)) |
| 1361 | lladdr = neigh->ha; |
| 1362 | } else { |
| 1363 | /* No address is supplied; if we know something, |
| 1364 | use it, otherwise discard the request. |
| 1365 | */ |
| 1366 | err = -EINVAL; |
| 1367 | if (!(old & NUD_VALID)) { |
| 1368 | NL_SET_ERR_MSG(extack, "No link layer address given"); |
| 1369 | goto out; |
| 1370 | } |
| 1371 | lladdr = neigh->ha; |
| 1372 | } |
| 1373 | |
| 1374 | /* Update confirmed timestamp for neighbour entry after we |
| 1375 | * received ARP packet even if it doesn't change IP to MAC binding. |
| 1376 | */ |
| 1377 | if (new & NUD_CONNECTED) |
| 1378 | neigh->confirmed = jiffies; |
| 1379 | |
| 1380 | /* If entry was valid and address is not changed, |
| 1381 | do not change entry state, if new one is STALE. |
| 1382 | */ |
| 1383 | err = 0; |
| 1384 | update_isrouter = flags & NEIGH_UPDATE_F_OVERRIDE_ISROUTER; |
| 1385 | if (old & NUD_VALID) { |
| 1386 | if (lladdr != neigh->ha && !(flags & NEIGH_UPDATE_F_OVERRIDE)) { |
| 1387 | update_isrouter = 0; |
| 1388 | if ((flags & NEIGH_UPDATE_F_WEAK_OVERRIDE) && |
| 1389 | (old & NUD_CONNECTED)) { |
| 1390 | lladdr = neigh->ha; |
| 1391 | new = NUD_STALE; |
| 1392 | } else |
| 1393 | goto out; |
| 1394 | } else { |
| 1395 | if (lladdr == neigh->ha && new == NUD_STALE && |
| 1396 | !(flags & NEIGH_UPDATE_F_ADMIN)) |
| 1397 | new = old; |
| 1398 | } |
| 1399 | } |
| 1400 | |
| 1401 | /* Update timestamp only once we know we will make a change to the |
| 1402 | * neighbour entry. Otherwise we risk to move the locktime window with |
| 1403 | * noop updates and ignore relevant ARP updates. |
| 1404 | */ |
| 1405 | if (new != old || lladdr != neigh->ha) |
| 1406 | neigh->updated = jiffies; |
| 1407 | |
| 1408 | if (new != old) { |
| 1409 | neigh_del_timer(neigh); |
| 1410 | if (new & NUD_PROBE) |
| 1411 | atomic_set(&neigh->probes, 0); |
| 1412 | if (new & NUD_IN_TIMER) |
| 1413 | neigh_add_timer(neigh, (jiffies + |
| 1414 | ((new & NUD_REACHABLE) ? |
| 1415 | neigh->parms->reachable_time : |
| 1416 | 0))); |
| 1417 | WRITE_ONCE(neigh->nud_state, new); |
| 1418 | notify = 1; |
| 1419 | } |
| 1420 | |
| 1421 | if (lladdr != neigh->ha) { |
| 1422 | write_seqlock(&neigh->ha_lock); |
| 1423 | memcpy(&neigh->ha, lladdr, dev->addr_len); |
| 1424 | write_sequnlock(&neigh->ha_lock); |
| 1425 | neigh_update_hhs(neigh); |
| 1426 | if (!(new & NUD_CONNECTED)) |
| 1427 | neigh->confirmed = jiffies - |
| 1428 | (NEIGH_VAR(neigh->parms, BASE_REACHABLE_TIME) << 1); |
| 1429 | notify = 1; |
| 1430 | } |
| 1431 | if (new == old) |
| 1432 | goto out; |
| 1433 | if (new & NUD_CONNECTED) |
| 1434 | neigh_connect(neigh); |
| 1435 | else |
| 1436 | neigh_suspect(neigh); |
| 1437 | if (!(old & NUD_VALID)) { |
| 1438 | struct sk_buff *skb; |
| 1439 | |
| 1440 | /* Again: avoid dead loop if something went wrong */ |
| 1441 | |
| 1442 | while (neigh->nud_state & NUD_VALID && |
| 1443 | (skb = __skb_dequeue(&neigh->arp_queue)) != NULL) { |
| 1444 | struct dst_entry *dst = skb_dst(skb); |
| 1445 | struct neighbour *n2, *n1 = neigh; |
| 1446 | write_unlock_bh(&neigh->lock); |
| 1447 | |
| 1448 | rcu_read_lock(); |
| 1449 | |
| 1450 | /* Why not just use 'neigh' as-is? The problem is that |
| 1451 | * things such as shaper, eql, and sch_teql can end up |
| 1452 | * using alternative, different, neigh objects to output |
| 1453 | * the packet in the output path. So what we need to do |
| 1454 | * here is re-lookup the top-level neigh in the path so |
| 1455 | * we can reinject the packet there. |
| 1456 | */ |
| 1457 | n2 = NULL; |
| 1458 | if (dst && dst->obsolete != DST_OBSOLETE_DEAD) { |
| 1459 | n2 = dst_neigh_lookup_skb(dst, skb); |
| 1460 | if (n2) |
| 1461 | n1 = n2; |
| 1462 | } |
| 1463 | READ_ONCE(n1->output)(n1, skb); |
| 1464 | if (n2) |
| 1465 | neigh_release(n2); |
| 1466 | rcu_read_unlock(); |
| 1467 | |
| 1468 | write_lock_bh(&neigh->lock); |
| 1469 | } |
| 1470 | __skb_queue_purge(&neigh->arp_queue); |
| 1471 | neigh->arp_queue_len_bytes = 0; |
| 1472 | } |
| 1473 | out: |
| 1474 | if (update_isrouter) |
| 1475 | neigh_update_is_router(neigh, flags, ¬ify); |
| 1476 | write_unlock_bh(&neigh->lock); |
| 1477 | if (((new ^ old) & NUD_PERMANENT) || gc_update) |
| 1478 | neigh_update_gc_list(neigh); |
| 1479 | if (managed_update) |
| 1480 | neigh_update_managed_list(neigh); |
| 1481 | if (notify) |
| 1482 | neigh_update_notify(neigh, nlmsg_pid); |
| 1483 | trace_neigh_update_done(neigh, err); |
| 1484 | return err; |
| 1485 | } |
| 1486 | |
| 1487 | int neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new, |
| 1488 | u32 flags, u32 nlmsg_pid) |
| 1489 | { |
| 1490 | return __neigh_update(neigh, lladdr, new, flags, nlmsg_pid, NULL); |
| 1491 | } |
| 1492 | EXPORT_SYMBOL(neigh_update); |
| 1493 | |
| 1494 | /* Update the neigh to listen temporarily for probe responses, even if it is |
| 1495 | * in a NUD_FAILED state. The caller has to hold neigh->lock for writing. |
| 1496 | */ |
| 1497 | void __neigh_set_probe_once(struct neighbour *neigh) |
| 1498 | { |
| 1499 | if (neigh->dead) |
| 1500 | return; |
| 1501 | neigh->updated = jiffies; |
| 1502 | if (!(neigh->nud_state & NUD_FAILED)) |
| 1503 | return; |
| 1504 | WRITE_ONCE(neigh->nud_state, NUD_INCOMPLETE); |
| 1505 | atomic_set(&neigh->probes, neigh_max_probes(neigh)); |
| 1506 | neigh_add_timer(neigh, |
| 1507 | jiffies + max(NEIGH_VAR(neigh->parms, RETRANS_TIME), |
| 1508 | HZ/100)); |
| 1509 | } |
| 1510 | EXPORT_SYMBOL(__neigh_set_probe_once); |
| 1511 | |
| 1512 | struct neighbour *neigh_event_ns(struct neigh_table *tbl, |
| 1513 | u8 *lladdr, void *saddr, |
| 1514 | struct net_device *dev) |
| 1515 | { |
| 1516 | struct neighbour *neigh = __neigh_lookup(tbl, saddr, dev, |
| 1517 | lladdr || !dev->addr_len); |
| 1518 | if (neigh) |
| 1519 | neigh_update(neigh, lladdr, NUD_STALE, |
| 1520 | NEIGH_UPDATE_F_OVERRIDE, 0); |
| 1521 | return neigh; |
| 1522 | } |
| 1523 | EXPORT_SYMBOL(neigh_event_ns); |
| 1524 | |
| 1525 | /* called with read_lock_bh(&n->lock); */ |
| 1526 | static void neigh_hh_init(struct neighbour *n) |
| 1527 | { |
| 1528 | struct net_device *dev = n->dev; |
| 1529 | __be16 prot = n->tbl->protocol; |
| 1530 | struct hh_cache *hh = &n->hh; |
| 1531 | |
| 1532 | write_lock_bh(&n->lock); |
| 1533 | |
| 1534 | /* Only one thread can come in here and initialize the |
| 1535 | * hh_cache entry. |
| 1536 | */ |
| 1537 | if (!hh->hh_len) |
| 1538 | dev->header_ops->cache(n, hh, prot); |
| 1539 | |
| 1540 | write_unlock_bh(&n->lock); |
| 1541 | } |
| 1542 | |
| 1543 | /* Slow and careful. */ |
| 1544 | |
| 1545 | int neigh_resolve_output(struct neighbour *neigh, struct sk_buff *skb) |
| 1546 | { |
| 1547 | int rc = 0; |
| 1548 | |
| 1549 | if (!neigh_event_send(neigh, skb)) { |
| 1550 | int err; |
| 1551 | struct net_device *dev = neigh->dev; |
| 1552 | unsigned int seq; |
| 1553 | |
| 1554 | if (dev->header_ops->cache && !READ_ONCE(neigh->hh.hh_len)) |
| 1555 | neigh_hh_init(neigh); |
| 1556 | |
| 1557 | do { |
| 1558 | __skb_pull(skb, skb_network_offset(skb)); |
| 1559 | seq = read_seqbegin(&neigh->ha_lock); |
| 1560 | err = dev_hard_header(skb, dev, ntohs(skb->protocol), |
| 1561 | neigh->ha, NULL, skb->len); |
| 1562 | } while (read_seqretry(&neigh->ha_lock, seq)); |
| 1563 | |
| 1564 | if (err >= 0) |
| 1565 | rc = dev_queue_xmit(skb); |
| 1566 | else |
| 1567 | goto out_kfree_skb; |
| 1568 | } |
| 1569 | out: |
| 1570 | return rc; |
| 1571 | out_kfree_skb: |
| 1572 | rc = -EINVAL; |
| 1573 | kfree_skb(skb); |
| 1574 | goto out; |
| 1575 | } |
| 1576 | EXPORT_SYMBOL(neigh_resolve_output); |
| 1577 | |
| 1578 | /* As fast as possible without hh cache */ |
| 1579 | |
| 1580 | int neigh_connected_output(struct neighbour *neigh, struct sk_buff *skb) |
| 1581 | { |
| 1582 | struct net_device *dev = neigh->dev; |
| 1583 | unsigned int seq; |
| 1584 | int err; |
| 1585 | |
| 1586 | do { |
| 1587 | __skb_pull(skb, skb_network_offset(skb)); |
| 1588 | seq = read_seqbegin(&neigh->ha_lock); |
| 1589 | err = dev_hard_header(skb, dev, ntohs(skb->protocol), |
| 1590 | neigh->ha, NULL, skb->len); |
| 1591 | } while (read_seqretry(&neigh->ha_lock, seq)); |
| 1592 | |
| 1593 | if (err >= 0) |
| 1594 | err = dev_queue_xmit(skb); |
| 1595 | else { |
| 1596 | err = -EINVAL; |
| 1597 | kfree_skb(skb); |
| 1598 | } |
| 1599 | return err; |
| 1600 | } |
| 1601 | EXPORT_SYMBOL(neigh_connected_output); |
| 1602 | |
| 1603 | int neigh_direct_output(struct neighbour *neigh, struct sk_buff *skb) |
| 1604 | { |
| 1605 | return dev_queue_xmit(skb); |
| 1606 | } |
| 1607 | EXPORT_SYMBOL(neigh_direct_output); |
| 1608 | |
| 1609 | static void neigh_managed_work(struct work_struct *work) |
| 1610 | { |
| 1611 | struct neigh_table *tbl = container_of(work, struct neigh_table, |
| 1612 | managed_work.work); |
| 1613 | struct neighbour *neigh; |
| 1614 | |
| 1615 | write_lock_bh(&tbl->lock); |
| 1616 | list_for_each_entry(neigh, &tbl->managed_list, managed_list) |
| 1617 | neigh_event_send_probe(neigh, NULL, false); |
| 1618 | queue_delayed_work(system_power_efficient_wq, &tbl->managed_work, |
| 1619 | NEIGH_VAR(&tbl->parms, INTERVAL_PROBE_TIME_MS)); |
| 1620 | write_unlock_bh(&tbl->lock); |
| 1621 | } |
| 1622 | |
| 1623 | static void neigh_proxy_process(struct timer_list *t) |
| 1624 | { |
| 1625 | struct neigh_table *tbl = from_timer(tbl, t, proxy_timer); |
| 1626 | long sched_next = 0; |
| 1627 | unsigned long now = jiffies; |
| 1628 | struct sk_buff *skb, *n; |
| 1629 | |
| 1630 | spin_lock(&tbl->proxy_queue.lock); |
| 1631 | |
| 1632 | skb_queue_walk_safe(&tbl->proxy_queue, skb, n) { |
| 1633 | long tdif = NEIGH_CB(skb)->sched_next - now; |
| 1634 | |
| 1635 | if (tdif <= 0) { |
| 1636 | struct net_device *dev = skb->dev; |
| 1637 | |
| 1638 | neigh_parms_qlen_dec(dev, tbl->family); |
| 1639 | __skb_unlink(skb, &tbl->proxy_queue); |
| 1640 | |
| 1641 | if (tbl->proxy_redo && netif_running(dev)) { |
| 1642 | rcu_read_lock(); |
| 1643 | tbl->proxy_redo(skb); |
| 1644 | rcu_read_unlock(); |
| 1645 | } else { |
| 1646 | kfree_skb(skb); |
| 1647 | } |
| 1648 | |
| 1649 | dev_put(dev); |
| 1650 | } else if (!sched_next || tdif < sched_next) |
| 1651 | sched_next = tdif; |
| 1652 | } |
| 1653 | del_timer(&tbl->proxy_timer); |
| 1654 | if (sched_next) |
| 1655 | mod_timer(&tbl->proxy_timer, jiffies + sched_next); |
| 1656 | spin_unlock(&tbl->proxy_queue.lock); |
| 1657 | } |
| 1658 | |
| 1659 | static unsigned long neigh_proxy_delay(struct neigh_parms *p) |
| 1660 | { |
| 1661 | /* If proxy_delay is zero, do not call get_random_u32_below() |
| 1662 | * as it is undefined behavior. |
| 1663 | */ |
| 1664 | unsigned long proxy_delay = NEIGH_VAR(p, PROXY_DELAY); |
| 1665 | |
| 1666 | return proxy_delay ? |
| 1667 | jiffies + get_random_u32_below(proxy_delay) : jiffies; |
| 1668 | } |
| 1669 | |
| 1670 | void pneigh_enqueue(struct neigh_table *tbl, struct neigh_parms *p, |
| 1671 | struct sk_buff *skb) |
| 1672 | { |
| 1673 | unsigned long sched_next = neigh_proxy_delay(p); |
| 1674 | |
| 1675 | if (p->qlen > NEIGH_VAR(p, PROXY_QLEN)) { |
| 1676 | kfree_skb(skb); |
| 1677 | return; |
| 1678 | } |
| 1679 | |
| 1680 | NEIGH_CB(skb)->sched_next = sched_next; |
| 1681 | NEIGH_CB(skb)->flags |= LOCALLY_ENQUEUED; |
| 1682 | |
| 1683 | spin_lock(&tbl->proxy_queue.lock); |
| 1684 | if (del_timer(&tbl->proxy_timer)) { |
| 1685 | if (time_before(tbl->proxy_timer.expires, sched_next)) |
| 1686 | sched_next = tbl->proxy_timer.expires; |
| 1687 | } |
| 1688 | skb_dst_drop(skb); |
| 1689 | dev_hold(skb->dev); |
| 1690 | __skb_queue_tail(&tbl->proxy_queue, skb); |
| 1691 | p->qlen++; |
| 1692 | mod_timer(&tbl->proxy_timer, sched_next); |
| 1693 | spin_unlock(&tbl->proxy_queue.lock); |
| 1694 | } |
| 1695 | EXPORT_SYMBOL(pneigh_enqueue); |
| 1696 | |
| 1697 | static inline struct neigh_parms *lookup_neigh_parms(struct neigh_table *tbl, |
| 1698 | struct net *net, int ifindex) |
| 1699 | { |
| 1700 | struct neigh_parms *p; |
| 1701 | |
| 1702 | list_for_each_entry(p, &tbl->parms_list, list) { |
| 1703 | if ((p->dev && p->dev->ifindex == ifindex && net_eq(neigh_parms_net(p), net)) || |
| 1704 | (!p->dev && !ifindex && net_eq(net, &init_net))) |
| 1705 | return p; |
| 1706 | } |
| 1707 | |
| 1708 | return NULL; |
| 1709 | } |
| 1710 | |
| 1711 | struct neigh_parms *neigh_parms_alloc(struct net_device *dev, |
| 1712 | struct neigh_table *tbl) |
| 1713 | { |
| 1714 | struct neigh_parms *p; |
| 1715 | struct net *net = dev_net(dev); |
| 1716 | const struct net_device_ops *ops = dev->netdev_ops; |
| 1717 | |
| 1718 | p = kmemdup(&tbl->parms, sizeof(*p), GFP_KERNEL); |
| 1719 | if (p) { |
| 1720 | p->tbl = tbl; |
| 1721 | refcount_set(&p->refcnt, 1); |
| 1722 | p->reachable_time = |
| 1723 | neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME)); |
| 1724 | p->qlen = 0; |
| 1725 | netdev_hold(dev, &p->dev_tracker, GFP_KERNEL); |
| 1726 | p->dev = dev; |
| 1727 | write_pnet(&p->net, net); |
| 1728 | p->sysctl_table = NULL; |
| 1729 | |
| 1730 | if (ops->ndo_neigh_setup && ops->ndo_neigh_setup(dev, p)) { |
| 1731 | netdev_put(dev, &p->dev_tracker); |
| 1732 | kfree(p); |
| 1733 | return NULL; |
| 1734 | } |
| 1735 | |
| 1736 | write_lock_bh(&tbl->lock); |
| 1737 | list_add(&p->list, &tbl->parms.list); |
| 1738 | write_unlock_bh(&tbl->lock); |
| 1739 | |
| 1740 | neigh_parms_data_state_cleanall(p); |
| 1741 | } |
| 1742 | return p; |
| 1743 | } |
| 1744 | EXPORT_SYMBOL(neigh_parms_alloc); |
| 1745 | |
| 1746 | static void neigh_rcu_free_parms(struct rcu_head *head) |
| 1747 | { |
| 1748 | struct neigh_parms *parms = |
| 1749 | container_of(head, struct neigh_parms, rcu_head); |
| 1750 | |
| 1751 | neigh_parms_put(parms); |
| 1752 | } |
| 1753 | |
| 1754 | void neigh_parms_release(struct neigh_table *tbl, struct neigh_parms *parms) |
| 1755 | { |
| 1756 | if (!parms || parms == &tbl->parms) |
| 1757 | return; |
| 1758 | write_lock_bh(&tbl->lock); |
| 1759 | list_del(&parms->list); |
| 1760 | parms->dead = 1; |
| 1761 | write_unlock_bh(&tbl->lock); |
| 1762 | netdev_put(parms->dev, &parms->dev_tracker); |
| 1763 | call_rcu(&parms->rcu_head, neigh_rcu_free_parms); |
| 1764 | } |
| 1765 | EXPORT_SYMBOL(neigh_parms_release); |
| 1766 | |
| 1767 | static void neigh_parms_destroy(struct neigh_parms *parms) |
| 1768 | { |
| 1769 | kfree(parms); |
| 1770 | } |
| 1771 | |
| 1772 | static struct lock_class_key neigh_table_proxy_queue_class; |
| 1773 | |
| 1774 | static struct neigh_table __rcu *neigh_tables[NEIGH_NR_TABLES] __read_mostly; |
| 1775 | |
| 1776 | void neigh_table_init(int index, struct neigh_table *tbl) |
| 1777 | { |
| 1778 | unsigned long now = jiffies; |
| 1779 | unsigned long phsize; |
| 1780 | |
| 1781 | INIT_LIST_HEAD(&tbl->parms_list); |
| 1782 | INIT_LIST_HEAD(&tbl->gc_list); |
| 1783 | INIT_LIST_HEAD(&tbl->managed_list); |
| 1784 | |
| 1785 | list_add(&tbl->parms.list, &tbl->parms_list); |
| 1786 | write_pnet(&tbl->parms.net, &init_net); |
| 1787 | refcount_set(&tbl->parms.refcnt, 1); |
| 1788 | tbl->parms.reachable_time = |
| 1789 | neigh_rand_reach_time(NEIGH_VAR(&tbl->parms, BASE_REACHABLE_TIME)); |
| 1790 | tbl->parms.qlen = 0; |
| 1791 | |
| 1792 | tbl->stats = alloc_percpu(struct neigh_statistics); |
| 1793 | if (!tbl->stats) |
| 1794 | panic("cannot create neighbour cache statistics"); |
| 1795 | |
| 1796 | #ifdef CONFIG_PROC_FS |
| 1797 | if (!proc_create_seq_data(tbl->id, 0, init_net.proc_net_stat, |
| 1798 | &neigh_stat_seq_ops, tbl)) |
| 1799 | panic("cannot create neighbour proc dir entry"); |
| 1800 | #endif |
| 1801 | |
| 1802 | RCU_INIT_POINTER(tbl->nht, neigh_hash_alloc(3)); |
| 1803 | |
| 1804 | phsize = (PNEIGH_HASHMASK + 1) * sizeof(struct pneigh_entry *); |
| 1805 | tbl->phash_buckets = kzalloc(phsize, GFP_KERNEL); |
| 1806 | |
| 1807 | if (!tbl->nht || !tbl->phash_buckets) |
| 1808 | panic("cannot allocate neighbour cache hashes"); |
| 1809 | |
| 1810 | if (!tbl->entry_size) |
| 1811 | tbl->entry_size = ALIGN(offsetof(struct neighbour, primary_key) + |
| 1812 | tbl->key_len, NEIGH_PRIV_ALIGN); |
| 1813 | else |
| 1814 | WARN_ON(tbl->entry_size % NEIGH_PRIV_ALIGN); |
| 1815 | |
| 1816 | rwlock_init(&tbl->lock); |
| 1817 | |
| 1818 | INIT_DEFERRABLE_WORK(&tbl->gc_work, neigh_periodic_work); |
| 1819 | queue_delayed_work(system_power_efficient_wq, &tbl->gc_work, |
| 1820 | tbl->parms.reachable_time); |
| 1821 | INIT_DEFERRABLE_WORK(&tbl->managed_work, neigh_managed_work); |
| 1822 | queue_delayed_work(system_power_efficient_wq, &tbl->managed_work, 0); |
| 1823 | |
| 1824 | timer_setup(&tbl->proxy_timer, neigh_proxy_process, 0); |
| 1825 | skb_queue_head_init_class(&tbl->proxy_queue, |
| 1826 | &neigh_table_proxy_queue_class); |
| 1827 | |
| 1828 | tbl->last_flush = now; |
| 1829 | tbl->last_rand = now + tbl->parms.reachable_time * 20; |
| 1830 | |
| 1831 | rcu_assign_pointer(neigh_tables[index], tbl); |
| 1832 | } |
| 1833 | EXPORT_SYMBOL(neigh_table_init); |
| 1834 | |
| 1835 | /* |
| 1836 | * Only called from ndisc_cleanup(), which means this is dead code |
| 1837 | * because we no longer can unload IPv6 module. |
| 1838 | */ |
| 1839 | int neigh_table_clear(int index, struct neigh_table *tbl) |
| 1840 | { |
| 1841 | RCU_INIT_POINTER(neigh_tables[index], NULL); |
| 1842 | synchronize_rcu(); |
| 1843 | |
| 1844 | /* It is not clean... Fix it to unload IPv6 module safely */ |
| 1845 | cancel_delayed_work_sync(&tbl->managed_work); |
| 1846 | cancel_delayed_work_sync(&tbl->gc_work); |
| 1847 | del_timer_sync(&tbl->proxy_timer); |
| 1848 | pneigh_queue_purge(&tbl->proxy_queue, NULL, tbl->family); |
| 1849 | neigh_ifdown(tbl, NULL); |
| 1850 | if (atomic_read(&tbl->entries)) |
| 1851 | pr_crit("neighbour leakage\n"); |
| 1852 | |
| 1853 | call_rcu(&rcu_dereference_protected(tbl->nht, 1)->rcu, |
| 1854 | neigh_hash_free_rcu); |
| 1855 | tbl->nht = NULL; |
| 1856 | |
| 1857 | kfree(tbl->phash_buckets); |
| 1858 | tbl->phash_buckets = NULL; |
| 1859 | |
| 1860 | remove_proc_entry(tbl->id, init_net.proc_net_stat); |
| 1861 | |
| 1862 | free_percpu(tbl->stats); |
| 1863 | tbl->stats = NULL; |
| 1864 | |
| 1865 | return 0; |
| 1866 | } |
| 1867 | EXPORT_SYMBOL(neigh_table_clear); |
| 1868 | |
| 1869 | static struct neigh_table *neigh_find_table(int family) |
| 1870 | { |
| 1871 | struct neigh_table *tbl = NULL; |
| 1872 | |
| 1873 | switch (family) { |
| 1874 | case AF_INET: |
| 1875 | tbl = rcu_dereference_rtnl(neigh_tables[NEIGH_ARP_TABLE]); |
| 1876 | break; |
| 1877 | case AF_INET6: |
| 1878 | tbl = rcu_dereference_rtnl(neigh_tables[NEIGH_ND_TABLE]); |
| 1879 | break; |
| 1880 | } |
| 1881 | |
| 1882 | return tbl; |
| 1883 | } |
| 1884 | |
| 1885 | const struct nla_policy nda_policy[NDA_MAX+1] = { |
| 1886 | [NDA_UNSPEC] = { .strict_start_type = NDA_NH_ID }, |
| 1887 | [NDA_DST] = { .type = NLA_BINARY, .len = MAX_ADDR_LEN }, |
| 1888 | [NDA_LLADDR] = { .type = NLA_BINARY, .len = MAX_ADDR_LEN }, |
| 1889 | [NDA_CACHEINFO] = { .len = sizeof(struct nda_cacheinfo) }, |
| 1890 | [NDA_PROBES] = { .type = NLA_U32 }, |
| 1891 | [NDA_VLAN] = { .type = NLA_U16 }, |
| 1892 | [NDA_PORT] = { .type = NLA_U16 }, |
| 1893 | [NDA_VNI] = { .type = NLA_U32 }, |
| 1894 | [NDA_IFINDEX] = { .type = NLA_U32 }, |
| 1895 | [NDA_MASTER] = { .type = NLA_U32 }, |
| 1896 | [NDA_PROTOCOL] = { .type = NLA_U8 }, |
| 1897 | [NDA_NH_ID] = { .type = NLA_U32 }, |
| 1898 | [NDA_FLAGS_EXT] = NLA_POLICY_MASK(NLA_U32, NTF_EXT_MASK), |
| 1899 | [NDA_FDB_EXT_ATTRS] = { .type = NLA_NESTED }, |
| 1900 | }; |
| 1901 | |
| 1902 | static int neigh_delete(struct sk_buff *skb, struct nlmsghdr *nlh, |
| 1903 | struct netlink_ext_ack *extack) |
| 1904 | { |
| 1905 | struct net *net = sock_net(skb->sk); |
| 1906 | struct ndmsg *ndm; |
| 1907 | struct nlattr *dst_attr; |
| 1908 | struct neigh_table *tbl; |
| 1909 | struct neighbour *neigh; |
| 1910 | struct net_device *dev = NULL; |
| 1911 | int err = -EINVAL; |
| 1912 | |
| 1913 | ASSERT_RTNL(); |
| 1914 | if (nlmsg_len(nlh) < sizeof(*ndm)) |
| 1915 | goto out; |
| 1916 | |
| 1917 | dst_attr = nlmsg_find_attr(nlh, sizeof(*ndm), NDA_DST); |
| 1918 | if (!dst_attr) { |
| 1919 | NL_SET_ERR_MSG(extack, "Network address not specified"); |
| 1920 | goto out; |
| 1921 | } |
| 1922 | |
| 1923 | ndm = nlmsg_data(nlh); |
| 1924 | if (ndm->ndm_ifindex) { |
| 1925 | dev = __dev_get_by_index(net, ndm->ndm_ifindex); |
| 1926 | if (dev == NULL) { |
| 1927 | err = -ENODEV; |
| 1928 | goto out; |
| 1929 | } |
| 1930 | } |
| 1931 | |
| 1932 | tbl = neigh_find_table(ndm->ndm_family); |
| 1933 | if (tbl == NULL) |
| 1934 | return -EAFNOSUPPORT; |
| 1935 | |
| 1936 | if (nla_len(dst_attr) < (int)tbl->key_len) { |
| 1937 | NL_SET_ERR_MSG(extack, "Invalid network address"); |
| 1938 | goto out; |
| 1939 | } |
| 1940 | |
| 1941 | if (ndm->ndm_flags & NTF_PROXY) { |
| 1942 | err = pneigh_delete(tbl, net, nla_data(dst_attr), dev); |
| 1943 | goto out; |
| 1944 | } |
| 1945 | |
| 1946 | if (dev == NULL) |
| 1947 | goto out; |
| 1948 | |
| 1949 | neigh = neigh_lookup(tbl, nla_data(dst_attr), dev); |
| 1950 | if (neigh == NULL) { |
| 1951 | err = -ENOENT; |
| 1952 | goto out; |
| 1953 | } |
| 1954 | |
| 1955 | err = __neigh_update(neigh, NULL, NUD_FAILED, |
| 1956 | NEIGH_UPDATE_F_OVERRIDE | NEIGH_UPDATE_F_ADMIN, |
| 1957 | NETLINK_CB(skb).portid, extack); |
| 1958 | write_lock_bh(&tbl->lock); |
| 1959 | neigh_release(neigh); |
| 1960 | neigh_remove_one(neigh, tbl); |
| 1961 | write_unlock_bh(&tbl->lock); |
| 1962 | |
| 1963 | out: |
| 1964 | return err; |
| 1965 | } |
| 1966 | |
| 1967 | static int neigh_add(struct sk_buff *skb, struct nlmsghdr *nlh, |
| 1968 | struct netlink_ext_ack *extack) |
| 1969 | { |
| 1970 | int flags = NEIGH_UPDATE_F_ADMIN | NEIGH_UPDATE_F_OVERRIDE | |
| 1971 | NEIGH_UPDATE_F_OVERRIDE_ISROUTER; |
| 1972 | struct net *net = sock_net(skb->sk); |
| 1973 | struct ndmsg *ndm; |
| 1974 | struct nlattr *tb[NDA_MAX+1]; |
| 1975 | struct neigh_table *tbl; |
| 1976 | struct net_device *dev = NULL; |
| 1977 | struct neighbour *neigh; |
| 1978 | void *dst, *lladdr; |
| 1979 | u8 protocol = 0; |
| 1980 | u32 ndm_flags; |
| 1981 | int err; |
| 1982 | |
| 1983 | ASSERT_RTNL(); |
| 1984 | err = nlmsg_parse_deprecated(nlh, sizeof(*ndm), tb, NDA_MAX, |
| 1985 | nda_policy, extack); |
| 1986 | if (err < 0) |
| 1987 | goto out; |
| 1988 | |
| 1989 | err = -EINVAL; |
| 1990 | if (!tb[NDA_DST]) { |
| 1991 | NL_SET_ERR_MSG(extack, "Network address not specified"); |
| 1992 | goto out; |
| 1993 | } |
| 1994 | |
| 1995 | ndm = nlmsg_data(nlh); |
| 1996 | ndm_flags = ndm->ndm_flags; |
| 1997 | if (tb[NDA_FLAGS_EXT]) { |
| 1998 | u32 ext = nla_get_u32(tb[NDA_FLAGS_EXT]); |
| 1999 | |
| 2000 | BUILD_BUG_ON(sizeof(neigh->flags) * BITS_PER_BYTE < |
| 2001 | (sizeof(ndm->ndm_flags) * BITS_PER_BYTE + |
| 2002 | hweight32(NTF_EXT_MASK))); |
| 2003 | ndm_flags |= (ext << NTF_EXT_SHIFT); |
| 2004 | } |
| 2005 | if (ndm->ndm_ifindex) { |
| 2006 | dev = __dev_get_by_index(net, ndm->ndm_ifindex); |
| 2007 | if (dev == NULL) { |
| 2008 | err = -ENODEV; |
| 2009 | goto out; |
| 2010 | } |
| 2011 | |
| 2012 | if (tb[NDA_LLADDR] && nla_len(tb[NDA_LLADDR]) < dev->addr_len) { |
| 2013 | NL_SET_ERR_MSG(extack, "Invalid link address"); |
| 2014 | goto out; |
| 2015 | } |
| 2016 | } |
| 2017 | |
| 2018 | tbl = neigh_find_table(ndm->ndm_family); |
| 2019 | if (tbl == NULL) |
| 2020 | return -EAFNOSUPPORT; |
| 2021 | |
| 2022 | if (nla_len(tb[NDA_DST]) < (int)tbl->key_len) { |
| 2023 | NL_SET_ERR_MSG(extack, "Invalid network address"); |
| 2024 | goto out; |
| 2025 | } |
| 2026 | |
| 2027 | dst = nla_data(tb[NDA_DST]); |
| 2028 | lladdr = tb[NDA_LLADDR] ? nla_data(tb[NDA_LLADDR]) : NULL; |
| 2029 | |
| 2030 | if (tb[NDA_PROTOCOL]) |
| 2031 | protocol = nla_get_u8(tb[NDA_PROTOCOL]); |
| 2032 | if (ndm_flags & NTF_PROXY) { |
| 2033 | struct pneigh_entry *pn; |
| 2034 | |
| 2035 | if (ndm_flags & NTF_MANAGED) { |
| 2036 | NL_SET_ERR_MSG(extack, "Invalid NTF_* flag combination"); |
| 2037 | goto out; |
| 2038 | } |
| 2039 | |
| 2040 | err = -ENOBUFS; |
| 2041 | pn = pneigh_lookup(tbl, net, dst, dev, 1); |
| 2042 | if (pn) { |
| 2043 | pn->flags = ndm_flags; |
| 2044 | if (protocol) |
| 2045 | pn->protocol = protocol; |
| 2046 | err = 0; |
| 2047 | } |
| 2048 | goto out; |
| 2049 | } |
| 2050 | |
| 2051 | if (!dev) { |
| 2052 | NL_SET_ERR_MSG(extack, "Device not specified"); |
| 2053 | goto out; |
| 2054 | } |
| 2055 | |
| 2056 | if (tbl->allow_add && !tbl->allow_add(dev, extack)) { |
| 2057 | err = -EINVAL; |
| 2058 | goto out; |
| 2059 | } |
| 2060 | |
| 2061 | neigh = neigh_lookup(tbl, dst, dev); |
| 2062 | if (neigh == NULL) { |
| 2063 | bool ndm_permanent = ndm->ndm_state & NUD_PERMANENT; |
| 2064 | bool exempt_from_gc = ndm_permanent || |
| 2065 | ndm_flags & NTF_EXT_LEARNED; |
| 2066 | |
| 2067 | if (!(nlh->nlmsg_flags & NLM_F_CREATE)) { |
| 2068 | err = -ENOENT; |
| 2069 | goto out; |
| 2070 | } |
| 2071 | if (ndm_permanent && (ndm_flags & NTF_MANAGED)) { |
| 2072 | NL_SET_ERR_MSG(extack, "Invalid NTF_* flag for permanent entry"); |
| 2073 | err = -EINVAL; |
| 2074 | goto out; |
| 2075 | } |
| 2076 | |
| 2077 | neigh = ___neigh_create(tbl, dst, dev, |
| 2078 | ndm_flags & |
| 2079 | (NTF_EXT_LEARNED | NTF_MANAGED), |
| 2080 | exempt_from_gc, true); |
| 2081 | if (IS_ERR(neigh)) { |
| 2082 | err = PTR_ERR(neigh); |
| 2083 | goto out; |
| 2084 | } |
| 2085 | } else { |
| 2086 | if (nlh->nlmsg_flags & NLM_F_EXCL) { |
| 2087 | err = -EEXIST; |
| 2088 | neigh_release(neigh); |
| 2089 | goto out; |
| 2090 | } |
| 2091 | |
| 2092 | if (!(nlh->nlmsg_flags & NLM_F_REPLACE)) |
| 2093 | flags &= ~(NEIGH_UPDATE_F_OVERRIDE | |
| 2094 | NEIGH_UPDATE_F_OVERRIDE_ISROUTER); |
| 2095 | } |
| 2096 | |
| 2097 | if (protocol) |
| 2098 | neigh->protocol = protocol; |
| 2099 | if (ndm_flags & NTF_EXT_LEARNED) |
| 2100 | flags |= NEIGH_UPDATE_F_EXT_LEARNED; |
| 2101 | if (ndm_flags & NTF_ROUTER) |
| 2102 | flags |= NEIGH_UPDATE_F_ISROUTER; |
| 2103 | if (ndm_flags & NTF_MANAGED) |
| 2104 | flags |= NEIGH_UPDATE_F_MANAGED; |
| 2105 | if (ndm_flags & NTF_USE) |
| 2106 | flags |= NEIGH_UPDATE_F_USE; |
| 2107 | |
| 2108 | err = __neigh_update(neigh, lladdr, ndm->ndm_state, flags, |
| 2109 | NETLINK_CB(skb).portid, extack); |
| 2110 | if (!err && ndm_flags & (NTF_USE | NTF_MANAGED)) { |
| 2111 | neigh_event_send(neigh, NULL); |
| 2112 | err = 0; |
| 2113 | } |
| 2114 | neigh_release(neigh); |
| 2115 | out: |
| 2116 | return err; |
| 2117 | } |
| 2118 | |
| 2119 | static int neightbl_fill_parms(struct sk_buff *skb, struct neigh_parms *parms) |
| 2120 | { |
| 2121 | struct nlattr *nest; |
| 2122 | |
| 2123 | nest = nla_nest_start_noflag(skb, NDTA_PARMS); |
| 2124 | if (nest == NULL) |
| 2125 | return -ENOBUFS; |
| 2126 | |
| 2127 | if ((parms->dev && |
| 2128 | nla_put_u32(skb, NDTPA_IFINDEX, parms->dev->ifindex)) || |
| 2129 | nla_put_u32(skb, NDTPA_REFCNT, refcount_read(&parms->refcnt)) || |
| 2130 | nla_put_u32(skb, NDTPA_QUEUE_LENBYTES, |
| 2131 | NEIGH_VAR(parms, QUEUE_LEN_BYTES)) || |
| 2132 | /* approximative value for deprecated QUEUE_LEN (in packets) */ |
| 2133 | nla_put_u32(skb, NDTPA_QUEUE_LEN, |
| 2134 | NEIGH_VAR(parms, QUEUE_LEN_BYTES) / SKB_TRUESIZE(ETH_FRAME_LEN)) || |
| 2135 | nla_put_u32(skb, NDTPA_PROXY_QLEN, NEIGH_VAR(parms, PROXY_QLEN)) || |
| 2136 | nla_put_u32(skb, NDTPA_APP_PROBES, NEIGH_VAR(parms, APP_PROBES)) || |
| 2137 | nla_put_u32(skb, NDTPA_UCAST_PROBES, |
| 2138 | NEIGH_VAR(parms, UCAST_PROBES)) || |
| 2139 | nla_put_u32(skb, NDTPA_MCAST_PROBES, |
| 2140 | NEIGH_VAR(parms, MCAST_PROBES)) || |
| 2141 | nla_put_u32(skb, NDTPA_MCAST_REPROBES, |
| 2142 | NEIGH_VAR(parms, MCAST_REPROBES)) || |
| 2143 | nla_put_msecs(skb, NDTPA_REACHABLE_TIME, parms->reachable_time, |
| 2144 | NDTPA_PAD) || |
| 2145 | nla_put_msecs(skb, NDTPA_BASE_REACHABLE_TIME, |
| 2146 | NEIGH_VAR(parms, BASE_REACHABLE_TIME), NDTPA_PAD) || |
| 2147 | nla_put_msecs(skb, NDTPA_GC_STALETIME, |
| 2148 | NEIGH_VAR(parms, GC_STALETIME), NDTPA_PAD) || |
| 2149 | nla_put_msecs(skb, NDTPA_DELAY_PROBE_TIME, |
| 2150 | NEIGH_VAR(parms, DELAY_PROBE_TIME), NDTPA_PAD) || |
| 2151 | nla_put_msecs(skb, NDTPA_RETRANS_TIME, |
| 2152 | NEIGH_VAR(parms, RETRANS_TIME), NDTPA_PAD) || |
| 2153 | nla_put_msecs(skb, NDTPA_ANYCAST_DELAY, |
| 2154 | NEIGH_VAR(parms, ANYCAST_DELAY), NDTPA_PAD) || |
| 2155 | nla_put_msecs(skb, NDTPA_PROXY_DELAY, |
| 2156 | NEIGH_VAR(parms, PROXY_DELAY), NDTPA_PAD) || |
| 2157 | nla_put_msecs(skb, NDTPA_LOCKTIME, |
| 2158 | NEIGH_VAR(parms, LOCKTIME), NDTPA_PAD) || |
| 2159 | nla_put_msecs(skb, NDTPA_INTERVAL_PROBE_TIME_MS, |
| 2160 | NEIGH_VAR(parms, INTERVAL_PROBE_TIME_MS), NDTPA_PAD)) |
| 2161 | goto nla_put_failure; |
| 2162 | return nla_nest_end(skb, nest); |
| 2163 | |
| 2164 | nla_put_failure: |
| 2165 | nla_nest_cancel(skb, nest); |
| 2166 | return -EMSGSIZE; |
| 2167 | } |
| 2168 | |
| 2169 | static int neightbl_fill_info(struct sk_buff *skb, struct neigh_table *tbl, |
| 2170 | u32 pid, u32 seq, int type, int flags) |
| 2171 | { |
| 2172 | struct nlmsghdr *nlh; |
| 2173 | struct ndtmsg *ndtmsg; |
| 2174 | |
| 2175 | nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndtmsg), flags); |
| 2176 | if (nlh == NULL) |
| 2177 | return -EMSGSIZE; |
| 2178 | |
| 2179 | ndtmsg = nlmsg_data(nlh); |
| 2180 | |
| 2181 | read_lock_bh(&tbl->lock); |
| 2182 | ndtmsg->ndtm_family = tbl->family; |
| 2183 | ndtmsg->ndtm_pad1 = 0; |
| 2184 | ndtmsg->ndtm_pad2 = 0; |
| 2185 | |
| 2186 | if (nla_put_string(skb, NDTA_NAME, tbl->id) || |
| 2187 | nla_put_msecs(skb, NDTA_GC_INTERVAL, READ_ONCE(tbl->gc_interval), |
| 2188 | NDTA_PAD) || |
| 2189 | nla_put_u32(skb, NDTA_THRESH1, READ_ONCE(tbl->gc_thresh1)) || |
| 2190 | nla_put_u32(skb, NDTA_THRESH2, READ_ONCE(tbl->gc_thresh2)) || |
| 2191 | nla_put_u32(skb, NDTA_THRESH3, READ_ONCE(tbl->gc_thresh3))) |
| 2192 | goto nla_put_failure; |
| 2193 | { |
| 2194 | unsigned long now = jiffies; |
| 2195 | long flush_delta = now - READ_ONCE(tbl->last_flush); |
| 2196 | long rand_delta = now - READ_ONCE(tbl->last_rand); |
| 2197 | struct neigh_hash_table *nht; |
| 2198 | struct ndt_config ndc = { |
| 2199 | .ndtc_key_len = tbl->key_len, |
| 2200 | .ndtc_entry_size = tbl->entry_size, |
| 2201 | .ndtc_entries = atomic_read(&tbl->entries), |
| 2202 | .ndtc_last_flush = jiffies_to_msecs(flush_delta), |
| 2203 | .ndtc_last_rand = jiffies_to_msecs(rand_delta), |
| 2204 | .ndtc_proxy_qlen = READ_ONCE(tbl->proxy_queue.qlen), |
| 2205 | }; |
| 2206 | |
| 2207 | rcu_read_lock(); |
| 2208 | nht = rcu_dereference(tbl->nht); |
| 2209 | ndc.ndtc_hash_rnd = nht->hash_rnd[0]; |
| 2210 | ndc.ndtc_hash_mask = ((1 << nht->hash_shift) - 1); |
| 2211 | rcu_read_unlock(); |
| 2212 | |
| 2213 | if (nla_put(skb, NDTA_CONFIG, sizeof(ndc), &ndc)) |
| 2214 | goto nla_put_failure; |
| 2215 | } |
| 2216 | |
| 2217 | { |
| 2218 | int cpu; |
| 2219 | struct ndt_stats ndst; |
| 2220 | |
| 2221 | memset(&ndst, 0, sizeof(ndst)); |
| 2222 | |
| 2223 | for_each_possible_cpu(cpu) { |
| 2224 | struct neigh_statistics *st; |
| 2225 | |
| 2226 | st = per_cpu_ptr(tbl->stats, cpu); |
| 2227 | ndst.ndts_allocs += READ_ONCE(st->allocs); |
| 2228 | ndst.ndts_destroys += READ_ONCE(st->destroys); |
| 2229 | ndst.ndts_hash_grows += READ_ONCE(st->hash_grows); |
| 2230 | ndst.ndts_res_failed += READ_ONCE(st->res_failed); |
| 2231 | ndst.ndts_lookups += READ_ONCE(st->lookups); |
| 2232 | ndst.ndts_hits += READ_ONCE(st->hits); |
| 2233 | ndst.ndts_rcv_probes_mcast += READ_ONCE(st->rcv_probes_mcast); |
| 2234 | ndst.ndts_rcv_probes_ucast += READ_ONCE(st->rcv_probes_ucast); |
| 2235 | ndst.ndts_periodic_gc_runs += READ_ONCE(st->periodic_gc_runs); |
| 2236 | ndst.ndts_forced_gc_runs += READ_ONCE(st->forced_gc_runs); |
| 2237 | ndst.ndts_table_fulls += READ_ONCE(st->table_fulls); |
| 2238 | } |
| 2239 | |
| 2240 | if (nla_put_64bit(skb, NDTA_STATS, sizeof(ndst), &ndst, |
| 2241 | NDTA_PAD)) |
| 2242 | goto nla_put_failure; |
| 2243 | } |
| 2244 | |
| 2245 | BUG_ON(tbl->parms.dev); |
| 2246 | if (neightbl_fill_parms(skb, &tbl->parms) < 0) |
| 2247 | goto nla_put_failure; |
| 2248 | |
| 2249 | read_unlock_bh(&tbl->lock); |
| 2250 | nlmsg_end(skb, nlh); |
| 2251 | return 0; |
| 2252 | |
| 2253 | nla_put_failure: |
| 2254 | read_unlock_bh(&tbl->lock); |
| 2255 | nlmsg_cancel(skb, nlh); |
| 2256 | return -EMSGSIZE; |
| 2257 | } |
| 2258 | |
| 2259 | static int neightbl_fill_param_info(struct sk_buff *skb, |
| 2260 | struct neigh_table *tbl, |
| 2261 | struct neigh_parms *parms, |
| 2262 | u32 pid, u32 seq, int type, |
| 2263 | unsigned int flags) |
| 2264 | { |
| 2265 | struct ndtmsg *ndtmsg; |
| 2266 | struct nlmsghdr *nlh; |
| 2267 | |
| 2268 | nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndtmsg), flags); |
| 2269 | if (nlh == NULL) |
| 2270 | return -EMSGSIZE; |
| 2271 | |
| 2272 | ndtmsg = nlmsg_data(nlh); |
| 2273 | |
| 2274 | read_lock_bh(&tbl->lock); |
| 2275 | ndtmsg->ndtm_family = tbl->family; |
| 2276 | ndtmsg->ndtm_pad1 = 0; |
| 2277 | ndtmsg->ndtm_pad2 = 0; |
| 2278 | |
| 2279 | if (nla_put_string(skb, NDTA_NAME, tbl->id) < 0 || |
| 2280 | neightbl_fill_parms(skb, parms) < 0) |
| 2281 | goto errout; |
| 2282 | |
| 2283 | read_unlock_bh(&tbl->lock); |
| 2284 | nlmsg_end(skb, nlh); |
| 2285 | return 0; |
| 2286 | errout: |
| 2287 | read_unlock_bh(&tbl->lock); |
| 2288 | nlmsg_cancel(skb, nlh); |
| 2289 | return -EMSGSIZE; |
| 2290 | } |
| 2291 | |
| 2292 | static const struct nla_policy nl_neightbl_policy[NDTA_MAX+1] = { |
| 2293 | [NDTA_NAME] = { .type = NLA_STRING }, |
| 2294 | [NDTA_THRESH1] = { .type = NLA_U32 }, |
| 2295 | [NDTA_THRESH2] = { .type = NLA_U32 }, |
| 2296 | [NDTA_THRESH3] = { .type = NLA_U32 }, |
| 2297 | [NDTA_GC_INTERVAL] = { .type = NLA_U64 }, |
| 2298 | [NDTA_PARMS] = { .type = NLA_NESTED }, |
| 2299 | }; |
| 2300 | |
| 2301 | static const struct nla_policy nl_ntbl_parm_policy[NDTPA_MAX+1] = { |
| 2302 | [NDTPA_IFINDEX] = { .type = NLA_U32 }, |
| 2303 | [NDTPA_QUEUE_LEN] = { .type = NLA_U32 }, |
| 2304 | [NDTPA_PROXY_QLEN] = { .type = NLA_U32 }, |
| 2305 | [NDTPA_APP_PROBES] = { .type = NLA_U32 }, |
| 2306 | [NDTPA_UCAST_PROBES] = { .type = NLA_U32 }, |
| 2307 | [NDTPA_MCAST_PROBES] = { .type = NLA_U32 }, |
| 2308 | [NDTPA_MCAST_REPROBES] = { .type = NLA_U32 }, |
| 2309 | [NDTPA_BASE_REACHABLE_TIME] = { .type = NLA_U64 }, |
| 2310 | [NDTPA_GC_STALETIME] = { .type = NLA_U64 }, |
| 2311 | [NDTPA_DELAY_PROBE_TIME] = { .type = NLA_U64 }, |
| 2312 | [NDTPA_RETRANS_TIME] = { .type = NLA_U64 }, |
| 2313 | [NDTPA_ANYCAST_DELAY] = { .type = NLA_U64 }, |
| 2314 | [NDTPA_PROXY_DELAY] = { .type = NLA_U64 }, |
| 2315 | [NDTPA_LOCKTIME] = { .type = NLA_U64 }, |
| 2316 | [NDTPA_INTERVAL_PROBE_TIME_MS] = { .type = NLA_U64, .min = 1 }, |
| 2317 | }; |
| 2318 | |
| 2319 | static int neightbl_set(struct sk_buff *skb, struct nlmsghdr *nlh, |
| 2320 | struct netlink_ext_ack *extack) |
| 2321 | { |
| 2322 | struct net *net = sock_net(skb->sk); |
| 2323 | struct neigh_table *tbl; |
| 2324 | struct ndtmsg *ndtmsg; |
| 2325 | struct nlattr *tb[NDTA_MAX+1]; |
| 2326 | bool found = false; |
| 2327 | int err, tidx; |
| 2328 | |
| 2329 | err = nlmsg_parse_deprecated(nlh, sizeof(*ndtmsg), tb, NDTA_MAX, |
| 2330 | nl_neightbl_policy, extack); |
| 2331 | if (err < 0) |
| 2332 | goto errout; |
| 2333 | |
| 2334 | if (tb[NDTA_NAME] == NULL) { |
| 2335 | err = -EINVAL; |
| 2336 | goto errout; |
| 2337 | } |
| 2338 | |
| 2339 | ndtmsg = nlmsg_data(nlh); |
| 2340 | |
| 2341 | for (tidx = 0; tidx < NEIGH_NR_TABLES; tidx++) { |
| 2342 | tbl = rcu_dereference_rtnl(neigh_tables[tidx]); |
| 2343 | if (!tbl) |
| 2344 | continue; |
| 2345 | if (ndtmsg->ndtm_family && tbl->family != ndtmsg->ndtm_family) |
| 2346 | continue; |
| 2347 | if (nla_strcmp(tb[NDTA_NAME], tbl->id) == 0) { |
| 2348 | found = true; |
| 2349 | break; |
| 2350 | } |
| 2351 | } |
| 2352 | |
| 2353 | if (!found) |
| 2354 | return -ENOENT; |
| 2355 | |
| 2356 | /* |
| 2357 | * We acquire tbl->lock to be nice to the periodic timers and |
| 2358 | * make sure they always see a consistent set of values. |
| 2359 | */ |
| 2360 | write_lock_bh(&tbl->lock); |
| 2361 | |
| 2362 | if (tb[NDTA_PARMS]) { |
| 2363 | struct nlattr *tbp[NDTPA_MAX+1]; |
| 2364 | struct neigh_parms *p; |
| 2365 | int i, ifindex = 0; |
| 2366 | |
| 2367 | err = nla_parse_nested_deprecated(tbp, NDTPA_MAX, |
| 2368 | tb[NDTA_PARMS], |
| 2369 | nl_ntbl_parm_policy, extack); |
| 2370 | if (err < 0) |
| 2371 | goto errout_tbl_lock; |
| 2372 | |
| 2373 | if (tbp[NDTPA_IFINDEX]) |
| 2374 | ifindex = nla_get_u32(tbp[NDTPA_IFINDEX]); |
| 2375 | |
| 2376 | p = lookup_neigh_parms(tbl, net, ifindex); |
| 2377 | if (p == NULL) { |
| 2378 | err = -ENOENT; |
| 2379 | goto errout_tbl_lock; |
| 2380 | } |
| 2381 | |
| 2382 | for (i = 1; i <= NDTPA_MAX; i++) { |
| 2383 | if (tbp[i] == NULL) |
| 2384 | continue; |
| 2385 | |
| 2386 | switch (i) { |
| 2387 | case NDTPA_QUEUE_LEN: |
| 2388 | NEIGH_VAR_SET(p, QUEUE_LEN_BYTES, |
| 2389 | nla_get_u32(tbp[i]) * |
| 2390 | SKB_TRUESIZE(ETH_FRAME_LEN)); |
| 2391 | break; |
| 2392 | case NDTPA_QUEUE_LENBYTES: |
| 2393 | NEIGH_VAR_SET(p, QUEUE_LEN_BYTES, |
| 2394 | nla_get_u32(tbp[i])); |
| 2395 | break; |
| 2396 | case NDTPA_PROXY_QLEN: |
| 2397 | NEIGH_VAR_SET(p, PROXY_QLEN, |
| 2398 | nla_get_u32(tbp[i])); |
| 2399 | break; |
| 2400 | case NDTPA_APP_PROBES: |
| 2401 | NEIGH_VAR_SET(p, APP_PROBES, |
| 2402 | nla_get_u32(tbp[i])); |
| 2403 | break; |
| 2404 | case NDTPA_UCAST_PROBES: |
| 2405 | NEIGH_VAR_SET(p, UCAST_PROBES, |
| 2406 | nla_get_u32(tbp[i])); |
| 2407 | break; |
| 2408 | case NDTPA_MCAST_PROBES: |
| 2409 | NEIGH_VAR_SET(p, MCAST_PROBES, |
| 2410 | nla_get_u32(tbp[i])); |
| 2411 | break; |
| 2412 | case NDTPA_MCAST_REPROBES: |
| 2413 | NEIGH_VAR_SET(p, MCAST_REPROBES, |
| 2414 | nla_get_u32(tbp[i])); |
| 2415 | break; |
| 2416 | case NDTPA_BASE_REACHABLE_TIME: |
| 2417 | NEIGH_VAR_SET(p, BASE_REACHABLE_TIME, |
| 2418 | nla_get_msecs(tbp[i])); |
| 2419 | /* update reachable_time as well, otherwise, the change will |
| 2420 | * only be effective after the next time neigh_periodic_work |
| 2421 | * decides to recompute it (can be multiple minutes) |
| 2422 | */ |
| 2423 | p->reachable_time = |
| 2424 | neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME)); |
| 2425 | break; |
| 2426 | case NDTPA_GC_STALETIME: |
| 2427 | NEIGH_VAR_SET(p, GC_STALETIME, |
| 2428 | nla_get_msecs(tbp[i])); |
| 2429 | break; |
| 2430 | case NDTPA_DELAY_PROBE_TIME: |
| 2431 | NEIGH_VAR_SET(p, DELAY_PROBE_TIME, |
| 2432 | nla_get_msecs(tbp[i])); |
| 2433 | call_netevent_notifiers(NETEVENT_DELAY_PROBE_TIME_UPDATE, p); |
| 2434 | break; |
| 2435 | case NDTPA_INTERVAL_PROBE_TIME_MS: |
| 2436 | NEIGH_VAR_SET(p, INTERVAL_PROBE_TIME_MS, |
| 2437 | nla_get_msecs(tbp[i])); |
| 2438 | break; |
| 2439 | case NDTPA_RETRANS_TIME: |
| 2440 | NEIGH_VAR_SET(p, RETRANS_TIME, |
| 2441 | nla_get_msecs(tbp[i])); |
| 2442 | break; |
| 2443 | case NDTPA_ANYCAST_DELAY: |
| 2444 | NEIGH_VAR_SET(p, ANYCAST_DELAY, |
| 2445 | nla_get_msecs(tbp[i])); |
| 2446 | break; |
| 2447 | case NDTPA_PROXY_DELAY: |
| 2448 | NEIGH_VAR_SET(p, PROXY_DELAY, |
| 2449 | nla_get_msecs(tbp[i])); |
| 2450 | break; |
| 2451 | case NDTPA_LOCKTIME: |
| 2452 | NEIGH_VAR_SET(p, LOCKTIME, |
| 2453 | nla_get_msecs(tbp[i])); |
| 2454 | break; |
| 2455 | } |
| 2456 | } |
| 2457 | } |
| 2458 | |
| 2459 | err = -ENOENT; |
| 2460 | if ((tb[NDTA_THRESH1] || tb[NDTA_THRESH2] || |
| 2461 | tb[NDTA_THRESH3] || tb[NDTA_GC_INTERVAL]) && |
| 2462 | !net_eq(net, &init_net)) |
| 2463 | goto errout_tbl_lock; |
| 2464 | |
| 2465 | if (tb[NDTA_THRESH1]) |
| 2466 | WRITE_ONCE(tbl->gc_thresh1, nla_get_u32(tb[NDTA_THRESH1])); |
| 2467 | |
| 2468 | if (tb[NDTA_THRESH2]) |
| 2469 | WRITE_ONCE(tbl->gc_thresh2, nla_get_u32(tb[NDTA_THRESH2])); |
| 2470 | |
| 2471 | if (tb[NDTA_THRESH3]) |
| 2472 | WRITE_ONCE(tbl->gc_thresh3, nla_get_u32(tb[NDTA_THRESH3])); |
| 2473 | |
| 2474 | if (tb[NDTA_GC_INTERVAL]) |
| 2475 | WRITE_ONCE(tbl->gc_interval, nla_get_msecs(tb[NDTA_GC_INTERVAL])); |
| 2476 | |
| 2477 | err = 0; |
| 2478 | |
| 2479 | errout_tbl_lock: |
| 2480 | write_unlock_bh(&tbl->lock); |
| 2481 | errout: |
| 2482 | return err; |
| 2483 | } |
| 2484 | |
| 2485 | static int neightbl_valid_dump_info(const struct nlmsghdr *nlh, |
| 2486 | struct netlink_ext_ack *extack) |
| 2487 | { |
| 2488 | struct ndtmsg *ndtm; |
| 2489 | |
| 2490 | if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ndtm))) { |
| 2491 | NL_SET_ERR_MSG(extack, "Invalid header for neighbor table dump request"); |
| 2492 | return -EINVAL; |
| 2493 | } |
| 2494 | |
| 2495 | ndtm = nlmsg_data(nlh); |
| 2496 | if (ndtm->ndtm_pad1 || ndtm->ndtm_pad2) { |
| 2497 | NL_SET_ERR_MSG(extack, "Invalid values in header for neighbor table dump request"); |
| 2498 | return -EINVAL; |
| 2499 | } |
| 2500 | |
| 2501 | if (nlmsg_attrlen(nlh, sizeof(*ndtm))) { |
| 2502 | NL_SET_ERR_MSG(extack, "Invalid data after header in neighbor table dump request"); |
| 2503 | return -EINVAL; |
| 2504 | } |
| 2505 | |
| 2506 | return 0; |
| 2507 | } |
| 2508 | |
| 2509 | static int neightbl_dump_info(struct sk_buff *skb, struct netlink_callback *cb) |
| 2510 | { |
| 2511 | const struct nlmsghdr *nlh = cb->nlh; |
| 2512 | struct net *net = sock_net(skb->sk); |
| 2513 | int family, tidx, nidx = 0; |
| 2514 | int tbl_skip = cb->args[0]; |
| 2515 | int neigh_skip = cb->args[1]; |
| 2516 | struct neigh_table *tbl; |
| 2517 | |
| 2518 | if (cb->strict_check) { |
| 2519 | int err = neightbl_valid_dump_info(nlh, cb->extack); |
| 2520 | |
| 2521 | if (err < 0) |
| 2522 | return err; |
| 2523 | } |
| 2524 | |
| 2525 | family = ((struct rtgenmsg *)nlmsg_data(nlh))->rtgen_family; |
| 2526 | |
| 2527 | for (tidx = 0; tidx < NEIGH_NR_TABLES; tidx++) { |
| 2528 | struct neigh_parms *p; |
| 2529 | |
| 2530 | tbl = rcu_dereference_rtnl(neigh_tables[tidx]); |
| 2531 | if (!tbl) |
| 2532 | continue; |
| 2533 | |
| 2534 | if (tidx < tbl_skip || (family && tbl->family != family)) |
| 2535 | continue; |
| 2536 | |
| 2537 | if (neightbl_fill_info(skb, tbl, NETLINK_CB(cb->skb).portid, |
| 2538 | nlh->nlmsg_seq, RTM_NEWNEIGHTBL, |
| 2539 | NLM_F_MULTI) < 0) |
| 2540 | break; |
| 2541 | |
| 2542 | nidx = 0; |
| 2543 | p = list_next_entry(&tbl->parms, list); |
| 2544 | list_for_each_entry_from(p, &tbl->parms_list, list) { |
| 2545 | if (!net_eq(neigh_parms_net(p), net)) |
| 2546 | continue; |
| 2547 | |
| 2548 | if (nidx < neigh_skip) |
| 2549 | goto next; |
| 2550 | |
| 2551 | if (neightbl_fill_param_info(skb, tbl, p, |
| 2552 | NETLINK_CB(cb->skb).portid, |
| 2553 | nlh->nlmsg_seq, |
| 2554 | RTM_NEWNEIGHTBL, |
| 2555 | NLM_F_MULTI) < 0) |
| 2556 | goto out; |
| 2557 | next: |
| 2558 | nidx++; |
| 2559 | } |
| 2560 | |
| 2561 | neigh_skip = 0; |
| 2562 | } |
| 2563 | out: |
| 2564 | cb->args[0] = tidx; |
| 2565 | cb->args[1] = nidx; |
| 2566 | |
| 2567 | return skb->len; |
| 2568 | } |
| 2569 | |
| 2570 | static int neigh_fill_info(struct sk_buff *skb, struct neighbour *neigh, |
| 2571 | u32 pid, u32 seq, int type, unsigned int flags) |
| 2572 | { |
| 2573 | u32 neigh_flags, neigh_flags_ext; |
| 2574 | unsigned long now = jiffies; |
| 2575 | struct nda_cacheinfo ci; |
| 2576 | struct nlmsghdr *nlh; |
| 2577 | struct ndmsg *ndm; |
| 2578 | |
| 2579 | nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndm), flags); |
| 2580 | if (nlh == NULL) |
| 2581 | return -EMSGSIZE; |
| 2582 | |
| 2583 | neigh_flags_ext = neigh->flags >> NTF_EXT_SHIFT; |
| 2584 | neigh_flags = neigh->flags & NTF_OLD_MASK; |
| 2585 | |
| 2586 | ndm = nlmsg_data(nlh); |
| 2587 | ndm->ndm_family = neigh->ops->family; |
| 2588 | ndm->ndm_pad1 = 0; |
| 2589 | ndm->ndm_pad2 = 0; |
| 2590 | ndm->ndm_flags = neigh_flags; |
| 2591 | ndm->ndm_type = neigh->type; |
| 2592 | ndm->ndm_ifindex = neigh->dev->ifindex; |
| 2593 | |
| 2594 | if (nla_put(skb, NDA_DST, neigh->tbl->key_len, neigh->primary_key)) |
| 2595 | goto nla_put_failure; |
| 2596 | |
| 2597 | read_lock_bh(&neigh->lock); |
| 2598 | ndm->ndm_state = neigh->nud_state; |
| 2599 | if (neigh->nud_state & NUD_VALID) { |
| 2600 | char haddr[MAX_ADDR_LEN]; |
| 2601 | |
| 2602 | neigh_ha_snapshot(haddr, neigh, neigh->dev); |
| 2603 | if (nla_put(skb, NDA_LLADDR, neigh->dev->addr_len, haddr) < 0) { |
| 2604 | read_unlock_bh(&neigh->lock); |
| 2605 | goto nla_put_failure; |
| 2606 | } |
| 2607 | } |
| 2608 | |
| 2609 | ci.ndm_used = jiffies_to_clock_t(now - neigh->used); |
| 2610 | ci.ndm_confirmed = jiffies_to_clock_t(now - neigh->confirmed); |
| 2611 | ci.ndm_updated = jiffies_to_clock_t(now - neigh->updated); |
| 2612 | ci.ndm_refcnt = refcount_read(&neigh->refcnt) - 1; |
| 2613 | read_unlock_bh(&neigh->lock); |
| 2614 | |
| 2615 | if (nla_put_u32(skb, NDA_PROBES, atomic_read(&neigh->probes)) || |
| 2616 | nla_put(skb, NDA_CACHEINFO, sizeof(ci), &ci)) |
| 2617 | goto nla_put_failure; |
| 2618 | |
| 2619 | if (neigh->protocol && nla_put_u8(skb, NDA_PROTOCOL, neigh->protocol)) |
| 2620 | goto nla_put_failure; |
| 2621 | if (neigh_flags_ext && nla_put_u32(skb, NDA_FLAGS_EXT, neigh_flags_ext)) |
| 2622 | goto nla_put_failure; |
| 2623 | |
| 2624 | nlmsg_end(skb, nlh); |
| 2625 | return 0; |
| 2626 | |
| 2627 | nla_put_failure: |
| 2628 | nlmsg_cancel(skb, nlh); |
| 2629 | return -EMSGSIZE; |
| 2630 | } |
| 2631 | |
| 2632 | static int pneigh_fill_info(struct sk_buff *skb, struct pneigh_entry *pn, |
| 2633 | u32 pid, u32 seq, int type, unsigned int flags, |
| 2634 | struct neigh_table *tbl) |
| 2635 | { |
| 2636 | u32 neigh_flags, neigh_flags_ext; |
| 2637 | struct nlmsghdr *nlh; |
| 2638 | struct ndmsg *ndm; |
| 2639 | |
| 2640 | nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndm), flags); |
| 2641 | if (nlh == NULL) |
| 2642 | return -EMSGSIZE; |
| 2643 | |
| 2644 | neigh_flags_ext = pn->flags >> NTF_EXT_SHIFT; |
| 2645 | neigh_flags = pn->flags & NTF_OLD_MASK; |
| 2646 | |
| 2647 | ndm = nlmsg_data(nlh); |
| 2648 | ndm->ndm_family = tbl->family; |
| 2649 | ndm->ndm_pad1 = 0; |
| 2650 | ndm->ndm_pad2 = 0; |
| 2651 | ndm->ndm_flags = neigh_flags | NTF_PROXY; |
| 2652 | ndm->ndm_type = RTN_UNICAST; |
| 2653 | ndm->ndm_ifindex = pn->dev ? pn->dev->ifindex : 0; |
| 2654 | ndm->ndm_state = NUD_NONE; |
| 2655 | |
| 2656 | if (nla_put(skb, NDA_DST, tbl->key_len, pn->key)) |
| 2657 | goto nla_put_failure; |
| 2658 | |
| 2659 | if (pn->protocol && nla_put_u8(skb, NDA_PROTOCOL, pn->protocol)) |
| 2660 | goto nla_put_failure; |
| 2661 | if (neigh_flags_ext && nla_put_u32(skb, NDA_FLAGS_EXT, neigh_flags_ext)) |
| 2662 | goto nla_put_failure; |
| 2663 | |
| 2664 | nlmsg_end(skb, nlh); |
| 2665 | return 0; |
| 2666 | |
| 2667 | nla_put_failure: |
| 2668 | nlmsg_cancel(skb, nlh); |
| 2669 | return -EMSGSIZE; |
| 2670 | } |
| 2671 | |
| 2672 | static void neigh_update_notify(struct neighbour *neigh, u32 nlmsg_pid) |
| 2673 | { |
| 2674 | call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, neigh); |
| 2675 | __neigh_notify(neigh, RTM_NEWNEIGH, 0, nlmsg_pid); |
| 2676 | } |
| 2677 | |
| 2678 | static bool neigh_master_filtered(struct net_device *dev, int master_idx) |
| 2679 | { |
| 2680 | struct net_device *master; |
| 2681 | |
| 2682 | if (!master_idx) |
| 2683 | return false; |
| 2684 | |
| 2685 | master = dev ? netdev_master_upper_dev_get_rcu(dev) : NULL; |
| 2686 | |
| 2687 | /* 0 is already used to denote NDA_MASTER wasn't passed, therefore need another |
| 2688 | * invalid value for ifindex to denote "no master". |
| 2689 | */ |
| 2690 | if (master_idx == -1) |
| 2691 | return !!master; |
| 2692 | |
| 2693 | if (!master || master->ifindex != master_idx) |
| 2694 | return true; |
| 2695 | |
| 2696 | return false; |
| 2697 | } |
| 2698 | |
| 2699 | static bool neigh_ifindex_filtered(struct net_device *dev, int filter_idx) |
| 2700 | { |
| 2701 | if (filter_idx && (!dev || dev->ifindex != filter_idx)) |
| 2702 | return true; |
| 2703 | |
| 2704 | return false; |
| 2705 | } |
| 2706 | |
| 2707 | struct neigh_dump_filter { |
| 2708 | int master_idx; |
| 2709 | int dev_idx; |
| 2710 | }; |
| 2711 | |
| 2712 | static int neigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb, |
| 2713 | struct netlink_callback *cb, |
| 2714 | struct neigh_dump_filter *filter) |
| 2715 | { |
| 2716 | struct net *net = sock_net(skb->sk); |
| 2717 | struct neighbour *n; |
| 2718 | int err = 0, h, s_h = cb->args[1]; |
| 2719 | int idx, s_idx = idx = cb->args[2]; |
| 2720 | struct neigh_hash_table *nht; |
| 2721 | unsigned int flags = NLM_F_MULTI; |
| 2722 | |
| 2723 | if (filter->dev_idx || filter->master_idx) |
| 2724 | flags |= NLM_F_DUMP_FILTERED; |
| 2725 | |
| 2726 | nht = rcu_dereference(tbl->nht); |
| 2727 | |
| 2728 | for (h = s_h; h < (1 << nht->hash_shift); h++) { |
| 2729 | if (h > s_h) |
| 2730 | s_idx = 0; |
| 2731 | for (n = rcu_dereference(nht->hash_buckets[h]), idx = 0; |
| 2732 | n != NULL; |
| 2733 | n = rcu_dereference(n->next)) { |
| 2734 | if (idx < s_idx || !net_eq(dev_net(n->dev), net)) |
| 2735 | goto next; |
| 2736 | if (neigh_ifindex_filtered(n->dev, filter->dev_idx) || |
| 2737 | neigh_master_filtered(n->dev, filter->master_idx)) |
| 2738 | goto next; |
| 2739 | err = neigh_fill_info(skb, n, NETLINK_CB(cb->skb).portid, |
| 2740 | cb->nlh->nlmsg_seq, |
| 2741 | RTM_NEWNEIGH, flags); |
| 2742 | if (err < 0) |
| 2743 | goto out; |
| 2744 | next: |
| 2745 | idx++; |
| 2746 | } |
| 2747 | } |
| 2748 | out: |
| 2749 | cb->args[1] = h; |
| 2750 | cb->args[2] = idx; |
| 2751 | return err; |
| 2752 | } |
| 2753 | |
| 2754 | static int pneigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb, |
| 2755 | struct netlink_callback *cb, |
| 2756 | struct neigh_dump_filter *filter) |
| 2757 | { |
| 2758 | struct pneigh_entry *n; |
| 2759 | struct net *net = sock_net(skb->sk); |
| 2760 | int err = 0, h, s_h = cb->args[3]; |
| 2761 | int idx, s_idx = idx = cb->args[4]; |
| 2762 | unsigned int flags = NLM_F_MULTI; |
| 2763 | |
| 2764 | if (filter->dev_idx || filter->master_idx) |
| 2765 | flags |= NLM_F_DUMP_FILTERED; |
| 2766 | |
| 2767 | read_lock_bh(&tbl->lock); |
| 2768 | |
| 2769 | for (h = s_h; h <= PNEIGH_HASHMASK; h++) { |
| 2770 | if (h > s_h) |
| 2771 | s_idx = 0; |
| 2772 | for (n = tbl->phash_buckets[h], idx = 0; n; n = n->next) { |
| 2773 | if (idx < s_idx || pneigh_net(n) != net) |
| 2774 | goto next; |
| 2775 | if (neigh_ifindex_filtered(n->dev, filter->dev_idx) || |
| 2776 | neigh_master_filtered(n->dev, filter->master_idx)) |
| 2777 | goto next; |
| 2778 | err = pneigh_fill_info(skb, n, NETLINK_CB(cb->skb).portid, |
| 2779 | cb->nlh->nlmsg_seq, |
| 2780 | RTM_NEWNEIGH, flags, tbl); |
| 2781 | if (err < 0) { |
| 2782 | read_unlock_bh(&tbl->lock); |
| 2783 | goto out; |
| 2784 | } |
| 2785 | next: |
| 2786 | idx++; |
| 2787 | } |
| 2788 | } |
| 2789 | |
| 2790 | read_unlock_bh(&tbl->lock); |
| 2791 | out: |
| 2792 | cb->args[3] = h; |
| 2793 | cb->args[4] = idx; |
| 2794 | return err; |
| 2795 | } |
| 2796 | |
| 2797 | static int neigh_valid_dump_req(const struct nlmsghdr *nlh, |
| 2798 | bool strict_check, |
| 2799 | struct neigh_dump_filter *filter, |
| 2800 | struct netlink_ext_ack *extack) |
| 2801 | { |
| 2802 | struct nlattr *tb[NDA_MAX + 1]; |
| 2803 | int err, i; |
| 2804 | |
| 2805 | if (strict_check) { |
| 2806 | struct ndmsg *ndm; |
| 2807 | |
| 2808 | if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ndm))) { |
| 2809 | NL_SET_ERR_MSG(extack, "Invalid header for neighbor dump request"); |
| 2810 | return -EINVAL; |
| 2811 | } |
| 2812 | |
| 2813 | ndm = nlmsg_data(nlh); |
| 2814 | if (ndm->ndm_pad1 || ndm->ndm_pad2 || ndm->ndm_ifindex || |
| 2815 | ndm->ndm_state || ndm->ndm_type) { |
| 2816 | NL_SET_ERR_MSG(extack, "Invalid values in header for neighbor dump request"); |
| 2817 | return -EINVAL; |
| 2818 | } |
| 2819 | |
| 2820 | if (ndm->ndm_flags & ~NTF_PROXY) { |
| 2821 | NL_SET_ERR_MSG(extack, "Invalid flags in header for neighbor dump request"); |
| 2822 | return -EINVAL; |
| 2823 | } |
| 2824 | |
| 2825 | err = nlmsg_parse_deprecated_strict(nlh, sizeof(struct ndmsg), |
| 2826 | tb, NDA_MAX, nda_policy, |
| 2827 | extack); |
| 2828 | } else { |
| 2829 | err = nlmsg_parse_deprecated(nlh, sizeof(struct ndmsg), tb, |
| 2830 | NDA_MAX, nda_policy, extack); |
| 2831 | } |
| 2832 | if (err < 0) |
| 2833 | return err; |
| 2834 | |
| 2835 | for (i = 0; i <= NDA_MAX; ++i) { |
| 2836 | if (!tb[i]) |
| 2837 | continue; |
| 2838 | |
| 2839 | /* all new attributes should require strict_check */ |
| 2840 | switch (i) { |
| 2841 | case NDA_IFINDEX: |
| 2842 | filter->dev_idx = nla_get_u32(tb[i]); |
| 2843 | break; |
| 2844 | case NDA_MASTER: |
| 2845 | filter->master_idx = nla_get_u32(tb[i]); |
| 2846 | break; |
| 2847 | default: |
| 2848 | if (strict_check) { |
| 2849 | NL_SET_ERR_MSG(extack, "Unsupported attribute in neighbor dump request"); |
| 2850 | return -EINVAL; |
| 2851 | } |
| 2852 | } |
| 2853 | } |
| 2854 | |
| 2855 | return 0; |
| 2856 | } |
| 2857 | |
| 2858 | static int neigh_dump_info(struct sk_buff *skb, struct netlink_callback *cb) |
| 2859 | { |
| 2860 | const struct nlmsghdr *nlh = cb->nlh; |
| 2861 | struct neigh_dump_filter filter = {}; |
| 2862 | struct neigh_table *tbl; |
| 2863 | int t, family, s_t; |
| 2864 | int proxy = 0; |
| 2865 | int err; |
| 2866 | |
| 2867 | family = ((struct rtgenmsg *)nlmsg_data(nlh))->rtgen_family; |
| 2868 | |
| 2869 | /* check for full ndmsg structure presence, family member is |
| 2870 | * the same for both structures |
| 2871 | */ |
| 2872 | if (nlmsg_len(nlh) >= sizeof(struct ndmsg) && |
| 2873 | ((struct ndmsg *)nlmsg_data(nlh))->ndm_flags == NTF_PROXY) |
| 2874 | proxy = 1; |
| 2875 | |
| 2876 | err = neigh_valid_dump_req(nlh, cb->strict_check, &filter, cb->extack); |
| 2877 | if (err < 0 && cb->strict_check) |
| 2878 | return err; |
| 2879 | |
| 2880 | s_t = cb->args[0]; |
| 2881 | |
| 2882 | rcu_read_lock(); |
| 2883 | for (t = 0; t < NEIGH_NR_TABLES; t++) { |
| 2884 | tbl = rcu_dereference(neigh_tables[t]); |
| 2885 | |
| 2886 | if (!tbl) |
| 2887 | continue; |
| 2888 | if (t < s_t || (family && tbl->family != family)) |
| 2889 | continue; |
| 2890 | if (t > s_t) |
| 2891 | memset(&cb->args[1], 0, sizeof(cb->args) - |
| 2892 | sizeof(cb->args[0])); |
| 2893 | if (proxy) |
| 2894 | err = pneigh_dump_table(tbl, skb, cb, &filter); |
| 2895 | else |
| 2896 | err = neigh_dump_table(tbl, skb, cb, &filter); |
| 2897 | if (err < 0) |
| 2898 | break; |
| 2899 | } |
| 2900 | rcu_read_unlock(); |
| 2901 | |
| 2902 | cb->args[0] = t; |
| 2903 | return err; |
| 2904 | } |
| 2905 | |
| 2906 | static int neigh_valid_get_req(const struct nlmsghdr *nlh, |
| 2907 | struct neigh_table **tbl, |
| 2908 | void **dst, int *dev_idx, u8 *ndm_flags, |
| 2909 | struct netlink_ext_ack *extack) |
| 2910 | { |
| 2911 | struct nlattr *tb[NDA_MAX + 1]; |
| 2912 | struct ndmsg *ndm; |
| 2913 | int err, i; |
| 2914 | |
| 2915 | if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ndm))) { |
| 2916 | NL_SET_ERR_MSG(extack, "Invalid header for neighbor get request"); |
| 2917 | return -EINVAL; |
| 2918 | } |
| 2919 | |
| 2920 | ndm = nlmsg_data(nlh); |
| 2921 | if (ndm->ndm_pad1 || ndm->ndm_pad2 || ndm->ndm_state || |
| 2922 | ndm->ndm_type) { |
| 2923 | NL_SET_ERR_MSG(extack, "Invalid values in header for neighbor get request"); |
| 2924 | return -EINVAL; |
| 2925 | } |
| 2926 | |
| 2927 | if (ndm->ndm_flags & ~NTF_PROXY) { |
| 2928 | NL_SET_ERR_MSG(extack, "Invalid flags in header for neighbor get request"); |
| 2929 | return -EINVAL; |
| 2930 | } |
| 2931 | |
| 2932 | err = nlmsg_parse_deprecated_strict(nlh, sizeof(struct ndmsg), tb, |
| 2933 | NDA_MAX, nda_policy, extack); |
| 2934 | if (err < 0) |
| 2935 | return err; |
| 2936 | |
| 2937 | *ndm_flags = ndm->ndm_flags; |
| 2938 | *dev_idx = ndm->ndm_ifindex; |
| 2939 | *tbl = neigh_find_table(ndm->ndm_family); |
| 2940 | if (*tbl == NULL) { |
| 2941 | NL_SET_ERR_MSG(extack, "Unsupported family in header for neighbor get request"); |
| 2942 | return -EAFNOSUPPORT; |
| 2943 | } |
| 2944 | |
| 2945 | for (i = 0; i <= NDA_MAX; ++i) { |
| 2946 | if (!tb[i]) |
| 2947 | continue; |
| 2948 | |
| 2949 | switch (i) { |
| 2950 | case NDA_DST: |
| 2951 | if (nla_len(tb[i]) != (int)(*tbl)->key_len) { |
| 2952 | NL_SET_ERR_MSG(extack, "Invalid network address in neighbor get request"); |
| 2953 | return -EINVAL; |
| 2954 | } |
| 2955 | *dst = nla_data(tb[i]); |
| 2956 | break; |
| 2957 | default: |
| 2958 | NL_SET_ERR_MSG(extack, "Unsupported attribute in neighbor get request"); |
| 2959 | return -EINVAL; |
| 2960 | } |
| 2961 | } |
| 2962 | |
| 2963 | return 0; |
| 2964 | } |
| 2965 | |
| 2966 | static inline size_t neigh_nlmsg_size(void) |
| 2967 | { |
| 2968 | return NLMSG_ALIGN(sizeof(struct ndmsg)) |
| 2969 | + nla_total_size(MAX_ADDR_LEN) /* NDA_DST */ |
| 2970 | + nla_total_size(MAX_ADDR_LEN) /* NDA_LLADDR */ |
| 2971 | + nla_total_size(sizeof(struct nda_cacheinfo)) |
| 2972 | + nla_total_size(4) /* NDA_PROBES */ |
| 2973 | + nla_total_size(4) /* NDA_FLAGS_EXT */ |
| 2974 | + nla_total_size(1); /* NDA_PROTOCOL */ |
| 2975 | } |
| 2976 | |
| 2977 | static int neigh_get_reply(struct net *net, struct neighbour *neigh, |
| 2978 | u32 pid, u32 seq) |
| 2979 | { |
| 2980 | struct sk_buff *skb; |
| 2981 | int err = 0; |
| 2982 | |
| 2983 | skb = nlmsg_new(neigh_nlmsg_size(), GFP_KERNEL); |
| 2984 | if (!skb) |
| 2985 | return -ENOBUFS; |
| 2986 | |
| 2987 | err = neigh_fill_info(skb, neigh, pid, seq, RTM_NEWNEIGH, 0); |
| 2988 | if (err) { |
| 2989 | kfree_skb(skb); |
| 2990 | goto errout; |
| 2991 | } |
| 2992 | |
| 2993 | err = rtnl_unicast(skb, net, pid); |
| 2994 | errout: |
| 2995 | return err; |
| 2996 | } |
| 2997 | |
| 2998 | static inline size_t pneigh_nlmsg_size(void) |
| 2999 | { |
| 3000 | return NLMSG_ALIGN(sizeof(struct ndmsg)) |
| 3001 | + nla_total_size(MAX_ADDR_LEN) /* NDA_DST */ |
| 3002 | + nla_total_size(4) /* NDA_FLAGS_EXT */ |
| 3003 | + nla_total_size(1); /* NDA_PROTOCOL */ |
| 3004 | } |
| 3005 | |
| 3006 | static int pneigh_get_reply(struct net *net, struct pneigh_entry *neigh, |
| 3007 | u32 pid, u32 seq, struct neigh_table *tbl) |
| 3008 | { |
| 3009 | struct sk_buff *skb; |
| 3010 | int err = 0; |
| 3011 | |
| 3012 | skb = nlmsg_new(pneigh_nlmsg_size(), GFP_KERNEL); |
| 3013 | if (!skb) |
| 3014 | return -ENOBUFS; |
| 3015 | |
| 3016 | err = pneigh_fill_info(skb, neigh, pid, seq, RTM_NEWNEIGH, 0, tbl); |
| 3017 | if (err) { |
| 3018 | kfree_skb(skb); |
| 3019 | goto errout; |
| 3020 | } |
| 3021 | |
| 3022 | err = rtnl_unicast(skb, net, pid); |
| 3023 | errout: |
| 3024 | return err; |
| 3025 | } |
| 3026 | |
| 3027 | static int neigh_get(struct sk_buff *in_skb, struct nlmsghdr *nlh, |
| 3028 | struct netlink_ext_ack *extack) |
| 3029 | { |
| 3030 | struct net *net = sock_net(in_skb->sk); |
| 3031 | struct net_device *dev = NULL; |
| 3032 | struct neigh_table *tbl = NULL; |
| 3033 | struct neighbour *neigh; |
| 3034 | void *dst = NULL; |
| 3035 | u8 ndm_flags = 0; |
| 3036 | int dev_idx = 0; |
| 3037 | int err; |
| 3038 | |
| 3039 | err = neigh_valid_get_req(nlh, &tbl, &dst, &dev_idx, &ndm_flags, |
| 3040 | extack); |
| 3041 | if (err < 0) |
| 3042 | return err; |
| 3043 | |
| 3044 | if (dev_idx) { |
| 3045 | dev = __dev_get_by_index(net, dev_idx); |
| 3046 | if (!dev) { |
| 3047 | NL_SET_ERR_MSG(extack, "Unknown device ifindex"); |
| 3048 | return -ENODEV; |
| 3049 | } |
| 3050 | } |
| 3051 | |
| 3052 | if (!dst) { |
| 3053 | NL_SET_ERR_MSG(extack, "Network address not specified"); |
| 3054 | return -EINVAL; |
| 3055 | } |
| 3056 | |
| 3057 | if (ndm_flags & NTF_PROXY) { |
| 3058 | struct pneigh_entry *pn; |
| 3059 | |
| 3060 | pn = pneigh_lookup(tbl, net, dst, dev, 0); |
| 3061 | if (!pn) { |
| 3062 | NL_SET_ERR_MSG(extack, "Proxy neighbour entry not found"); |
| 3063 | return -ENOENT; |
| 3064 | } |
| 3065 | return pneigh_get_reply(net, pn, NETLINK_CB(in_skb).portid, |
| 3066 | nlh->nlmsg_seq, tbl); |
| 3067 | } |
| 3068 | |
| 3069 | if (!dev) { |
| 3070 | NL_SET_ERR_MSG(extack, "No device specified"); |
| 3071 | return -EINVAL; |
| 3072 | } |
| 3073 | |
| 3074 | neigh = neigh_lookup(tbl, dst, dev); |
| 3075 | if (!neigh) { |
| 3076 | NL_SET_ERR_MSG(extack, "Neighbour entry not found"); |
| 3077 | return -ENOENT; |
| 3078 | } |
| 3079 | |
| 3080 | err = neigh_get_reply(net, neigh, NETLINK_CB(in_skb).portid, |
| 3081 | nlh->nlmsg_seq); |
| 3082 | |
| 3083 | neigh_release(neigh); |
| 3084 | |
| 3085 | return err; |
| 3086 | } |
| 3087 | |
| 3088 | void neigh_for_each(struct neigh_table *tbl, void (*cb)(struct neighbour *, void *), void *cookie) |
| 3089 | { |
| 3090 | int chain; |
| 3091 | struct neigh_hash_table *nht; |
| 3092 | |
| 3093 | rcu_read_lock(); |
| 3094 | nht = rcu_dereference(tbl->nht); |
| 3095 | |
| 3096 | read_lock_bh(&tbl->lock); /* avoid resizes */ |
| 3097 | for (chain = 0; chain < (1 << nht->hash_shift); chain++) { |
| 3098 | struct neighbour *n; |
| 3099 | |
| 3100 | for (n = rcu_dereference(nht->hash_buckets[chain]); |
| 3101 | n != NULL; |
| 3102 | n = rcu_dereference(n->next)) |
| 3103 | cb(n, cookie); |
| 3104 | } |
| 3105 | read_unlock_bh(&tbl->lock); |
| 3106 | rcu_read_unlock(); |
| 3107 | } |
| 3108 | EXPORT_SYMBOL(neigh_for_each); |
| 3109 | |
| 3110 | /* The tbl->lock must be held as a writer and BH disabled. */ |
| 3111 | void __neigh_for_each_release(struct neigh_table *tbl, |
| 3112 | int (*cb)(struct neighbour *)) |
| 3113 | { |
| 3114 | int chain; |
| 3115 | struct neigh_hash_table *nht; |
| 3116 | |
| 3117 | nht = rcu_dereference_protected(tbl->nht, |
| 3118 | lockdep_is_held(&tbl->lock)); |
| 3119 | for (chain = 0; chain < (1 << nht->hash_shift); chain++) { |
| 3120 | struct neighbour *n; |
| 3121 | struct neighbour __rcu **np; |
| 3122 | |
| 3123 | np = &nht->hash_buckets[chain]; |
| 3124 | while ((n = rcu_dereference_protected(*np, |
| 3125 | lockdep_is_held(&tbl->lock))) != NULL) { |
| 3126 | int release; |
| 3127 | |
| 3128 | write_lock(&n->lock); |
| 3129 | release = cb(n); |
| 3130 | if (release) { |
| 3131 | rcu_assign_pointer(*np, |
| 3132 | rcu_dereference_protected(n->next, |
| 3133 | lockdep_is_held(&tbl->lock))); |
| 3134 | neigh_mark_dead(n); |
| 3135 | } else |
| 3136 | np = &n->next; |
| 3137 | write_unlock(&n->lock); |
| 3138 | if (release) |
| 3139 | neigh_cleanup_and_release(n); |
| 3140 | } |
| 3141 | } |
| 3142 | } |
| 3143 | EXPORT_SYMBOL(__neigh_for_each_release); |
| 3144 | |
| 3145 | int neigh_xmit(int index, struct net_device *dev, |
| 3146 | const void *addr, struct sk_buff *skb) |
| 3147 | { |
| 3148 | int err = -EAFNOSUPPORT; |
| 3149 | |
| 3150 | if (likely(index < NEIGH_NR_TABLES)) { |
| 3151 | struct neigh_table *tbl; |
| 3152 | struct neighbour *neigh; |
| 3153 | |
| 3154 | rcu_read_lock(); |
| 3155 | tbl = rcu_dereference(neigh_tables[index]); |
| 3156 | if (!tbl) |
| 3157 | goto out_unlock; |
| 3158 | if (index == NEIGH_ARP_TABLE) { |
| 3159 | u32 key = *((u32 *)addr); |
| 3160 | |
| 3161 | neigh = __ipv4_neigh_lookup_noref(dev, key); |
| 3162 | } else { |
| 3163 | neigh = __neigh_lookup_noref(tbl, addr, dev); |
| 3164 | } |
| 3165 | if (!neigh) |
| 3166 | neigh = __neigh_create(tbl, addr, dev, false); |
| 3167 | err = PTR_ERR(neigh); |
| 3168 | if (IS_ERR(neigh)) { |
| 3169 | rcu_read_unlock(); |
| 3170 | goto out_kfree_skb; |
| 3171 | } |
| 3172 | err = READ_ONCE(neigh->output)(neigh, skb); |
| 3173 | out_unlock: |
| 3174 | rcu_read_unlock(); |
| 3175 | } |
| 3176 | else if (index == NEIGH_LINK_TABLE) { |
| 3177 | err = dev_hard_header(skb, dev, ntohs(skb->protocol), |
| 3178 | addr, NULL, skb->len); |
| 3179 | if (err < 0) |
| 3180 | goto out_kfree_skb; |
| 3181 | err = dev_queue_xmit(skb); |
| 3182 | } |
| 3183 | out: |
| 3184 | return err; |
| 3185 | out_kfree_skb: |
| 3186 | kfree_skb(skb); |
| 3187 | goto out; |
| 3188 | } |
| 3189 | EXPORT_SYMBOL(neigh_xmit); |
| 3190 | |
| 3191 | #ifdef CONFIG_PROC_FS |
| 3192 | |
| 3193 | static struct neighbour *neigh_get_first(struct seq_file *seq) |
| 3194 | { |
| 3195 | struct neigh_seq_state *state = seq->private; |
| 3196 | struct net *net = seq_file_net(seq); |
| 3197 | struct neigh_hash_table *nht = state->nht; |
| 3198 | struct neighbour *n = NULL; |
| 3199 | int bucket; |
| 3200 | |
| 3201 | state->flags &= ~NEIGH_SEQ_IS_PNEIGH; |
| 3202 | for (bucket = 0; bucket < (1 << nht->hash_shift); bucket++) { |
| 3203 | n = rcu_dereference(nht->hash_buckets[bucket]); |
| 3204 | |
| 3205 | while (n) { |
| 3206 | if (!net_eq(dev_net(n->dev), net)) |
| 3207 | goto next; |
| 3208 | if (state->neigh_sub_iter) { |
| 3209 | loff_t fakep = 0; |
| 3210 | void *v; |
| 3211 | |
| 3212 | v = state->neigh_sub_iter(state, n, &fakep); |
| 3213 | if (!v) |
| 3214 | goto next; |
| 3215 | } |
| 3216 | if (!(state->flags & NEIGH_SEQ_SKIP_NOARP)) |
| 3217 | break; |
| 3218 | if (READ_ONCE(n->nud_state) & ~NUD_NOARP) |
| 3219 | break; |
| 3220 | next: |
| 3221 | n = rcu_dereference(n->next); |
| 3222 | } |
| 3223 | |
| 3224 | if (n) |
| 3225 | break; |
| 3226 | } |
| 3227 | state->bucket = bucket; |
| 3228 | |
| 3229 | return n; |
| 3230 | } |
| 3231 | |
| 3232 | static struct neighbour *neigh_get_next(struct seq_file *seq, |
| 3233 | struct neighbour *n, |
| 3234 | loff_t *pos) |
| 3235 | { |
| 3236 | struct neigh_seq_state *state = seq->private; |
| 3237 | struct net *net = seq_file_net(seq); |
| 3238 | struct neigh_hash_table *nht = state->nht; |
| 3239 | |
| 3240 | if (state->neigh_sub_iter) { |
| 3241 | void *v = state->neigh_sub_iter(state, n, pos); |
| 3242 | if (v) |
| 3243 | return n; |
| 3244 | } |
| 3245 | n = rcu_dereference(n->next); |
| 3246 | |
| 3247 | while (1) { |
| 3248 | while (n) { |
| 3249 | if (!net_eq(dev_net(n->dev), net)) |
| 3250 | goto next; |
| 3251 | if (state->neigh_sub_iter) { |
| 3252 | void *v = state->neigh_sub_iter(state, n, pos); |
| 3253 | if (v) |
| 3254 | return n; |
| 3255 | goto next; |
| 3256 | } |
| 3257 | if (!(state->flags & NEIGH_SEQ_SKIP_NOARP)) |
| 3258 | break; |
| 3259 | |
| 3260 | if (READ_ONCE(n->nud_state) & ~NUD_NOARP) |
| 3261 | break; |
| 3262 | next: |
| 3263 | n = rcu_dereference(n->next); |
| 3264 | } |
| 3265 | |
| 3266 | if (n) |
| 3267 | break; |
| 3268 | |
| 3269 | if (++state->bucket >= (1 << nht->hash_shift)) |
| 3270 | break; |
| 3271 | |
| 3272 | n = rcu_dereference(nht->hash_buckets[state->bucket]); |
| 3273 | } |
| 3274 | |
| 3275 | if (n && pos) |
| 3276 | --(*pos); |
| 3277 | return n; |
| 3278 | } |
| 3279 | |
| 3280 | static struct neighbour *neigh_get_idx(struct seq_file *seq, loff_t *pos) |
| 3281 | { |
| 3282 | struct neighbour *n = neigh_get_first(seq); |
| 3283 | |
| 3284 | if (n) { |
| 3285 | --(*pos); |
| 3286 | while (*pos) { |
| 3287 | n = neigh_get_next(seq, n, pos); |
| 3288 | if (!n) |
| 3289 | break; |
| 3290 | } |
| 3291 | } |
| 3292 | return *pos ? NULL : n; |
| 3293 | } |
| 3294 | |
| 3295 | static struct pneigh_entry *pneigh_get_first(struct seq_file *seq) |
| 3296 | { |
| 3297 | struct neigh_seq_state *state = seq->private; |
| 3298 | struct net *net = seq_file_net(seq); |
| 3299 | struct neigh_table *tbl = state->tbl; |
| 3300 | struct pneigh_entry *pn = NULL; |
| 3301 | int bucket; |
| 3302 | |
| 3303 | state->flags |= NEIGH_SEQ_IS_PNEIGH; |
| 3304 | for (bucket = 0; bucket <= PNEIGH_HASHMASK; bucket++) { |
| 3305 | pn = tbl->phash_buckets[bucket]; |
| 3306 | while (pn && !net_eq(pneigh_net(pn), net)) |
| 3307 | pn = pn->next; |
| 3308 | if (pn) |
| 3309 | break; |
| 3310 | } |
| 3311 | state->bucket = bucket; |
| 3312 | |
| 3313 | return pn; |
| 3314 | } |
| 3315 | |
| 3316 | static struct pneigh_entry *pneigh_get_next(struct seq_file *seq, |
| 3317 | struct pneigh_entry *pn, |
| 3318 | loff_t *pos) |
| 3319 | { |
| 3320 | struct neigh_seq_state *state = seq->private; |
| 3321 | struct net *net = seq_file_net(seq); |
| 3322 | struct neigh_table *tbl = state->tbl; |
| 3323 | |
| 3324 | do { |
| 3325 | pn = pn->next; |
| 3326 | } while (pn && !net_eq(pneigh_net(pn), net)); |
| 3327 | |
| 3328 | while (!pn) { |
| 3329 | if (++state->bucket > PNEIGH_HASHMASK) |
| 3330 | break; |
| 3331 | pn = tbl->phash_buckets[state->bucket]; |
| 3332 | while (pn && !net_eq(pneigh_net(pn), net)) |
| 3333 | pn = pn->next; |
| 3334 | if (pn) |
| 3335 | break; |
| 3336 | } |
| 3337 | |
| 3338 | if (pn && pos) |
| 3339 | --(*pos); |
| 3340 | |
| 3341 | return pn; |
| 3342 | } |
| 3343 | |
| 3344 | static struct pneigh_entry *pneigh_get_idx(struct seq_file *seq, loff_t *pos) |
| 3345 | { |
| 3346 | struct pneigh_entry *pn = pneigh_get_first(seq); |
| 3347 | |
| 3348 | if (pn) { |
| 3349 | --(*pos); |
| 3350 | while (*pos) { |
| 3351 | pn = pneigh_get_next(seq, pn, pos); |
| 3352 | if (!pn) |
| 3353 | break; |
| 3354 | } |
| 3355 | } |
| 3356 | return *pos ? NULL : pn; |
| 3357 | } |
| 3358 | |
| 3359 | static void *neigh_get_idx_any(struct seq_file *seq, loff_t *pos) |
| 3360 | { |
| 3361 | struct neigh_seq_state *state = seq->private; |
| 3362 | void *rc; |
| 3363 | loff_t idxpos = *pos; |
| 3364 | |
| 3365 | rc = neigh_get_idx(seq, &idxpos); |
| 3366 | if (!rc && !(state->flags & NEIGH_SEQ_NEIGH_ONLY)) |
| 3367 | rc = pneigh_get_idx(seq, &idxpos); |
| 3368 | |
| 3369 | return rc; |
| 3370 | } |
| 3371 | |
| 3372 | void *neigh_seq_start(struct seq_file *seq, loff_t *pos, struct neigh_table *tbl, unsigned int neigh_seq_flags) |
| 3373 | __acquires(tbl->lock) |
| 3374 | __acquires(rcu) |
| 3375 | { |
| 3376 | struct neigh_seq_state *state = seq->private; |
| 3377 | |
| 3378 | state->tbl = tbl; |
| 3379 | state->bucket = 0; |
| 3380 | state->flags = (neigh_seq_flags & ~NEIGH_SEQ_IS_PNEIGH); |
| 3381 | |
| 3382 | rcu_read_lock(); |
| 3383 | state->nht = rcu_dereference(tbl->nht); |
| 3384 | read_lock_bh(&tbl->lock); |
| 3385 | |
| 3386 | return *pos ? neigh_get_idx_any(seq, pos) : SEQ_START_TOKEN; |
| 3387 | } |
| 3388 | EXPORT_SYMBOL(neigh_seq_start); |
| 3389 | |
| 3390 | void *neigh_seq_next(struct seq_file *seq, void *v, loff_t *pos) |
| 3391 | { |
| 3392 | struct neigh_seq_state *state; |
| 3393 | void *rc; |
| 3394 | |
| 3395 | if (v == SEQ_START_TOKEN) { |
| 3396 | rc = neigh_get_first(seq); |
| 3397 | goto out; |
| 3398 | } |
| 3399 | |
| 3400 | state = seq->private; |
| 3401 | if (!(state->flags & NEIGH_SEQ_IS_PNEIGH)) { |
| 3402 | rc = neigh_get_next(seq, v, NULL); |
| 3403 | if (rc) |
| 3404 | goto out; |
| 3405 | if (!(state->flags & NEIGH_SEQ_NEIGH_ONLY)) |
| 3406 | rc = pneigh_get_first(seq); |
| 3407 | } else { |
| 3408 | BUG_ON(state->flags & NEIGH_SEQ_NEIGH_ONLY); |
| 3409 | rc = pneigh_get_next(seq, v, NULL); |
| 3410 | } |
| 3411 | out: |
| 3412 | ++(*pos); |
| 3413 | return rc; |
| 3414 | } |
| 3415 | EXPORT_SYMBOL(neigh_seq_next); |
| 3416 | |
| 3417 | void neigh_seq_stop(struct seq_file *seq, void *v) |
| 3418 | __releases(tbl->lock) |
| 3419 | __releases(rcu) |
| 3420 | { |
| 3421 | struct neigh_seq_state *state = seq->private; |
| 3422 | struct neigh_table *tbl = state->tbl; |
| 3423 | |
| 3424 | read_unlock_bh(&tbl->lock); |
| 3425 | rcu_read_unlock(); |
| 3426 | } |
| 3427 | EXPORT_SYMBOL(neigh_seq_stop); |
| 3428 | |
| 3429 | /* statistics via seq_file */ |
| 3430 | |
| 3431 | static void *neigh_stat_seq_start(struct seq_file *seq, loff_t *pos) |
| 3432 | { |
| 3433 | struct neigh_table *tbl = pde_data(file_inode(seq->file)); |
| 3434 | int cpu; |
| 3435 | |
| 3436 | if (*pos == 0) |
| 3437 | return SEQ_START_TOKEN; |
| 3438 | |
| 3439 | for (cpu = *pos-1; cpu < nr_cpu_ids; ++cpu) { |
| 3440 | if (!cpu_possible(cpu)) |
| 3441 | continue; |
| 3442 | *pos = cpu+1; |
| 3443 | return per_cpu_ptr(tbl->stats, cpu); |
| 3444 | } |
| 3445 | return NULL; |
| 3446 | } |
| 3447 | |
| 3448 | static void *neigh_stat_seq_next(struct seq_file *seq, void *v, loff_t *pos) |
| 3449 | { |
| 3450 | struct neigh_table *tbl = pde_data(file_inode(seq->file)); |
| 3451 | int cpu; |
| 3452 | |
| 3453 | for (cpu = *pos; cpu < nr_cpu_ids; ++cpu) { |
| 3454 | if (!cpu_possible(cpu)) |
| 3455 | continue; |
| 3456 | *pos = cpu+1; |
| 3457 | return per_cpu_ptr(tbl->stats, cpu); |
| 3458 | } |
| 3459 | (*pos)++; |
| 3460 | return NULL; |
| 3461 | } |
| 3462 | |
| 3463 | static void neigh_stat_seq_stop(struct seq_file *seq, void *v) |
| 3464 | { |
| 3465 | |
| 3466 | } |
| 3467 | |
| 3468 | static int neigh_stat_seq_show(struct seq_file *seq, void *v) |
| 3469 | { |
| 3470 | struct neigh_table *tbl = pde_data(file_inode(seq->file)); |
| 3471 | struct neigh_statistics *st = v; |
| 3472 | |
| 3473 | if (v == SEQ_START_TOKEN) { |
| 3474 | seq_puts(seq, "entries allocs destroys hash_grows lookups hits res_failed rcv_probes_mcast rcv_probes_ucast periodic_gc_runs forced_gc_runs unresolved_discards table_fulls\n"); |
| 3475 | return 0; |
| 3476 | } |
| 3477 | |
| 3478 | seq_printf(seq, "%08x %08lx %08lx %08lx %08lx %08lx %08lx " |
| 3479 | "%08lx %08lx %08lx " |
| 3480 | "%08lx %08lx %08lx\n", |
| 3481 | atomic_read(&tbl->entries), |
| 3482 | |
| 3483 | st->allocs, |
| 3484 | st->destroys, |
| 3485 | st->hash_grows, |
| 3486 | |
| 3487 | st->lookups, |
| 3488 | st->hits, |
| 3489 | |
| 3490 | st->res_failed, |
| 3491 | |
| 3492 | st->rcv_probes_mcast, |
| 3493 | st->rcv_probes_ucast, |
| 3494 | |
| 3495 | st->periodic_gc_runs, |
| 3496 | st->forced_gc_runs, |
| 3497 | st->unres_discards, |
| 3498 | st->table_fulls |
| 3499 | ); |
| 3500 | |
| 3501 | return 0; |
| 3502 | } |
| 3503 | |
| 3504 | static const struct seq_operations neigh_stat_seq_ops = { |
| 3505 | .start = neigh_stat_seq_start, |
| 3506 | .next = neigh_stat_seq_next, |
| 3507 | .stop = neigh_stat_seq_stop, |
| 3508 | .show = neigh_stat_seq_show, |
| 3509 | }; |
| 3510 | #endif /* CONFIG_PROC_FS */ |
| 3511 | |
| 3512 | static void __neigh_notify(struct neighbour *n, int type, int flags, |
| 3513 | u32 pid) |
| 3514 | { |
| 3515 | struct net *net = dev_net(n->dev); |
| 3516 | struct sk_buff *skb; |
| 3517 | int err = -ENOBUFS; |
| 3518 | |
| 3519 | skb = nlmsg_new(neigh_nlmsg_size(), GFP_ATOMIC); |
| 3520 | if (skb == NULL) |
| 3521 | goto errout; |
| 3522 | |
| 3523 | err = neigh_fill_info(skb, n, pid, 0, type, flags); |
| 3524 | if (err < 0) { |
| 3525 | /* -EMSGSIZE implies BUG in neigh_nlmsg_size() */ |
| 3526 | WARN_ON(err == -EMSGSIZE); |
| 3527 | kfree_skb(skb); |
| 3528 | goto errout; |
| 3529 | } |
| 3530 | rtnl_notify(skb, net, 0, RTNLGRP_NEIGH, NULL, GFP_ATOMIC); |
| 3531 | return; |
| 3532 | errout: |
| 3533 | if (err < 0) |
| 3534 | rtnl_set_sk_err(net, RTNLGRP_NEIGH, err); |
| 3535 | } |
| 3536 | |
| 3537 | void neigh_app_ns(struct neighbour *n) |
| 3538 | { |
| 3539 | __neigh_notify(n, RTM_GETNEIGH, NLM_F_REQUEST, 0); |
| 3540 | } |
| 3541 | EXPORT_SYMBOL(neigh_app_ns); |
| 3542 | |
| 3543 | #ifdef CONFIG_SYSCTL |
| 3544 | static int unres_qlen_max = INT_MAX / SKB_TRUESIZE(ETH_FRAME_LEN); |
| 3545 | |
| 3546 | static int proc_unres_qlen(const struct ctl_table *ctl, int write, |
| 3547 | void *buffer, size_t *lenp, loff_t *ppos) |
| 3548 | { |
| 3549 | int size, ret; |
| 3550 | struct ctl_table tmp = *ctl; |
| 3551 | |
| 3552 | tmp.extra1 = SYSCTL_ZERO; |
| 3553 | tmp.extra2 = &unres_qlen_max; |
| 3554 | tmp.data = &size; |
| 3555 | |
| 3556 | size = *(int *)ctl->data / SKB_TRUESIZE(ETH_FRAME_LEN); |
| 3557 | ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos); |
| 3558 | |
| 3559 | if (write && !ret) |
| 3560 | *(int *)ctl->data = size * SKB_TRUESIZE(ETH_FRAME_LEN); |
| 3561 | return ret; |
| 3562 | } |
| 3563 | |
| 3564 | static void neigh_copy_dflt_parms(struct net *net, struct neigh_parms *p, |
| 3565 | int index) |
| 3566 | { |
| 3567 | struct net_device *dev; |
| 3568 | int family = neigh_parms_family(p); |
| 3569 | |
| 3570 | rcu_read_lock(); |
| 3571 | for_each_netdev_rcu(net, dev) { |
| 3572 | struct neigh_parms *dst_p = |
| 3573 | neigh_get_dev_parms_rcu(dev, family); |
| 3574 | |
| 3575 | if (dst_p && !test_bit(index, dst_p->data_state)) |
| 3576 | dst_p->data[index] = p->data[index]; |
| 3577 | } |
| 3578 | rcu_read_unlock(); |
| 3579 | } |
| 3580 | |
| 3581 | static void neigh_proc_update(const struct ctl_table *ctl, int write) |
| 3582 | { |
| 3583 | struct net_device *dev = ctl->extra1; |
| 3584 | struct neigh_parms *p = ctl->extra2; |
| 3585 | struct net *net = neigh_parms_net(p); |
| 3586 | int index = (int *) ctl->data - p->data; |
| 3587 | |
| 3588 | if (!write) |
| 3589 | return; |
| 3590 | |
| 3591 | set_bit(index, p->data_state); |
| 3592 | if (index == NEIGH_VAR_DELAY_PROBE_TIME) |
| 3593 | call_netevent_notifiers(NETEVENT_DELAY_PROBE_TIME_UPDATE, p); |
| 3594 | if (!dev) /* NULL dev means this is default value */ |
| 3595 | neigh_copy_dflt_parms(net, p, index); |
| 3596 | } |
| 3597 | |
| 3598 | static int neigh_proc_dointvec_zero_intmax(const struct ctl_table *ctl, int write, |
| 3599 | void *buffer, size_t *lenp, |
| 3600 | loff_t *ppos) |
| 3601 | { |
| 3602 | struct ctl_table tmp = *ctl; |
| 3603 | int ret; |
| 3604 | |
| 3605 | tmp.extra1 = SYSCTL_ZERO; |
| 3606 | tmp.extra2 = SYSCTL_INT_MAX; |
| 3607 | |
| 3608 | ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos); |
| 3609 | neigh_proc_update(ctl, write); |
| 3610 | return ret; |
| 3611 | } |
| 3612 | |
| 3613 | static int neigh_proc_dointvec_ms_jiffies_positive(const struct ctl_table *ctl, int write, |
| 3614 | void *buffer, size_t *lenp, loff_t *ppos) |
| 3615 | { |
| 3616 | struct ctl_table tmp = *ctl; |
| 3617 | int ret; |
| 3618 | |
| 3619 | int min = msecs_to_jiffies(1); |
| 3620 | |
| 3621 | tmp.extra1 = &min; |
| 3622 | tmp.extra2 = NULL; |
| 3623 | |
| 3624 | ret = proc_dointvec_ms_jiffies_minmax(&tmp, write, buffer, lenp, ppos); |
| 3625 | neigh_proc_update(ctl, write); |
| 3626 | return ret; |
| 3627 | } |
| 3628 | |
| 3629 | int neigh_proc_dointvec(const struct ctl_table *ctl, int write, void *buffer, |
| 3630 | size_t *lenp, loff_t *ppos) |
| 3631 | { |
| 3632 | int ret = proc_dointvec(ctl, write, buffer, lenp, ppos); |
| 3633 | |
| 3634 | neigh_proc_update(ctl, write); |
| 3635 | return ret; |
| 3636 | } |
| 3637 | EXPORT_SYMBOL(neigh_proc_dointvec); |
| 3638 | |
| 3639 | int neigh_proc_dointvec_jiffies(const struct ctl_table *ctl, int write, void *buffer, |
| 3640 | size_t *lenp, loff_t *ppos) |
| 3641 | { |
| 3642 | int ret = proc_dointvec_jiffies(ctl, write, buffer, lenp, ppos); |
| 3643 | |
| 3644 | neigh_proc_update(ctl, write); |
| 3645 | return ret; |
| 3646 | } |
| 3647 | EXPORT_SYMBOL(neigh_proc_dointvec_jiffies); |
| 3648 | |
| 3649 | static int neigh_proc_dointvec_userhz_jiffies(const struct ctl_table *ctl, int write, |
| 3650 | void *buffer, size_t *lenp, |
| 3651 | loff_t *ppos) |
| 3652 | { |
| 3653 | int ret = proc_dointvec_userhz_jiffies(ctl, write, buffer, lenp, ppos); |
| 3654 | |
| 3655 | neigh_proc_update(ctl, write); |
| 3656 | return ret; |
| 3657 | } |
| 3658 | |
| 3659 | int neigh_proc_dointvec_ms_jiffies(const struct ctl_table *ctl, int write, |
| 3660 | void *buffer, size_t *lenp, loff_t *ppos) |
| 3661 | { |
| 3662 | int ret = proc_dointvec_ms_jiffies(ctl, write, buffer, lenp, ppos); |
| 3663 | |
| 3664 | neigh_proc_update(ctl, write); |
| 3665 | return ret; |
| 3666 | } |
| 3667 | EXPORT_SYMBOL(neigh_proc_dointvec_ms_jiffies); |
| 3668 | |
| 3669 | static int neigh_proc_dointvec_unres_qlen(const struct ctl_table *ctl, int write, |
| 3670 | void *buffer, size_t *lenp, |
| 3671 | loff_t *ppos) |
| 3672 | { |
| 3673 | int ret = proc_unres_qlen(ctl, write, buffer, lenp, ppos); |
| 3674 | |
| 3675 | neigh_proc_update(ctl, write); |
| 3676 | return ret; |
| 3677 | } |
| 3678 | |
| 3679 | static int neigh_proc_base_reachable_time(const struct ctl_table *ctl, int write, |
| 3680 | void *buffer, size_t *lenp, |
| 3681 | loff_t *ppos) |
| 3682 | { |
| 3683 | struct neigh_parms *p = ctl->extra2; |
| 3684 | int ret; |
| 3685 | |
| 3686 | if (strcmp(ctl->procname, "base_reachable_time") == 0) |
| 3687 | ret = neigh_proc_dointvec_jiffies(ctl, write, buffer, lenp, ppos); |
| 3688 | else if (strcmp(ctl->procname, "base_reachable_time_ms") == 0) |
| 3689 | ret = neigh_proc_dointvec_ms_jiffies(ctl, write, buffer, lenp, ppos); |
| 3690 | else |
| 3691 | ret = -1; |
| 3692 | |
| 3693 | if (write && ret == 0) { |
| 3694 | /* update reachable_time as well, otherwise, the change will |
| 3695 | * only be effective after the next time neigh_periodic_work |
| 3696 | * decides to recompute it |
| 3697 | */ |
| 3698 | p->reachable_time = |
| 3699 | neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME)); |
| 3700 | } |
| 3701 | return ret; |
| 3702 | } |
| 3703 | |
| 3704 | #define NEIGH_PARMS_DATA_OFFSET(index) \ |
| 3705 | (&((struct neigh_parms *) 0)->data[index]) |
| 3706 | |
| 3707 | #define NEIGH_SYSCTL_ENTRY(attr, data_attr, name, mval, proc) \ |
| 3708 | [NEIGH_VAR_ ## attr] = { \ |
| 3709 | .procname = name, \ |
| 3710 | .data = NEIGH_PARMS_DATA_OFFSET(NEIGH_VAR_ ## data_attr), \ |
| 3711 | .maxlen = sizeof(int), \ |
| 3712 | .mode = mval, \ |
| 3713 | .proc_handler = proc, \ |
| 3714 | } |
| 3715 | |
| 3716 | #define NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(attr, name) \ |
| 3717 | NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_zero_intmax) |
| 3718 | |
| 3719 | #define NEIGH_SYSCTL_JIFFIES_ENTRY(attr, name) \ |
| 3720 | NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_jiffies) |
| 3721 | |
| 3722 | #define NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(attr, name) \ |
| 3723 | NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_userhz_jiffies) |
| 3724 | |
| 3725 | #define NEIGH_SYSCTL_MS_JIFFIES_POSITIVE_ENTRY(attr, name) \ |
| 3726 | NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_ms_jiffies_positive) |
| 3727 | |
| 3728 | #define NEIGH_SYSCTL_MS_JIFFIES_REUSED_ENTRY(attr, data_attr, name) \ |
| 3729 | NEIGH_SYSCTL_ENTRY(attr, data_attr, name, 0644, neigh_proc_dointvec_ms_jiffies) |
| 3730 | |
| 3731 | #define NEIGH_SYSCTL_UNRES_QLEN_REUSED_ENTRY(attr, data_attr, name) \ |
| 3732 | NEIGH_SYSCTL_ENTRY(attr, data_attr, name, 0644, neigh_proc_dointvec_unres_qlen) |
| 3733 | |
| 3734 | static struct neigh_sysctl_table { |
| 3735 | struct ctl_table_header *sysctl_header; |
| 3736 | struct ctl_table neigh_vars[NEIGH_VAR_MAX]; |
| 3737 | } neigh_sysctl_template __read_mostly = { |
| 3738 | .neigh_vars = { |
| 3739 | NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(MCAST_PROBES, "mcast_solicit"), |
| 3740 | NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(UCAST_PROBES, "ucast_solicit"), |
| 3741 | NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(APP_PROBES, "app_solicit"), |
| 3742 | NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(MCAST_REPROBES, "mcast_resolicit"), |
| 3743 | NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(RETRANS_TIME, "retrans_time"), |
| 3744 | NEIGH_SYSCTL_JIFFIES_ENTRY(BASE_REACHABLE_TIME, "base_reachable_time"), |
| 3745 | NEIGH_SYSCTL_JIFFIES_ENTRY(DELAY_PROBE_TIME, "delay_first_probe_time"), |
| 3746 | NEIGH_SYSCTL_MS_JIFFIES_POSITIVE_ENTRY(INTERVAL_PROBE_TIME_MS, |
| 3747 | "interval_probe_time_ms"), |
| 3748 | NEIGH_SYSCTL_JIFFIES_ENTRY(GC_STALETIME, "gc_stale_time"), |
| 3749 | NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(QUEUE_LEN_BYTES, "unres_qlen_bytes"), |
| 3750 | NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(PROXY_QLEN, "proxy_qlen"), |
| 3751 | NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(ANYCAST_DELAY, "anycast_delay"), |
| 3752 | NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(PROXY_DELAY, "proxy_delay"), |
| 3753 | NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(LOCKTIME, "locktime"), |
| 3754 | NEIGH_SYSCTL_UNRES_QLEN_REUSED_ENTRY(QUEUE_LEN, QUEUE_LEN_BYTES, "unres_qlen"), |
| 3755 | NEIGH_SYSCTL_MS_JIFFIES_REUSED_ENTRY(RETRANS_TIME_MS, RETRANS_TIME, "retrans_time_ms"), |
| 3756 | NEIGH_SYSCTL_MS_JIFFIES_REUSED_ENTRY(BASE_REACHABLE_TIME_MS, BASE_REACHABLE_TIME, "base_reachable_time_ms"), |
| 3757 | [NEIGH_VAR_GC_INTERVAL] = { |
| 3758 | .procname = "gc_interval", |
| 3759 | .maxlen = sizeof(int), |
| 3760 | .mode = 0644, |
| 3761 | .proc_handler = proc_dointvec_jiffies, |
| 3762 | }, |
| 3763 | [NEIGH_VAR_GC_THRESH1] = { |
| 3764 | .procname = "gc_thresh1", |
| 3765 | .maxlen = sizeof(int), |
| 3766 | .mode = 0644, |
| 3767 | .extra1 = SYSCTL_ZERO, |
| 3768 | .extra2 = SYSCTL_INT_MAX, |
| 3769 | .proc_handler = proc_dointvec_minmax, |
| 3770 | }, |
| 3771 | [NEIGH_VAR_GC_THRESH2] = { |
| 3772 | .procname = "gc_thresh2", |
| 3773 | .maxlen = sizeof(int), |
| 3774 | .mode = 0644, |
| 3775 | .extra1 = SYSCTL_ZERO, |
| 3776 | .extra2 = SYSCTL_INT_MAX, |
| 3777 | .proc_handler = proc_dointvec_minmax, |
| 3778 | }, |
| 3779 | [NEIGH_VAR_GC_THRESH3] = { |
| 3780 | .procname = "gc_thresh3", |
| 3781 | .maxlen = sizeof(int), |
| 3782 | .mode = 0644, |
| 3783 | .extra1 = SYSCTL_ZERO, |
| 3784 | .extra2 = SYSCTL_INT_MAX, |
| 3785 | .proc_handler = proc_dointvec_minmax, |
| 3786 | }, |
| 3787 | }, |
| 3788 | }; |
| 3789 | |
| 3790 | int neigh_sysctl_register(struct net_device *dev, struct neigh_parms *p, |
| 3791 | proc_handler *handler) |
| 3792 | { |
| 3793 | int i; |
| 3794 | struct neigh_sysctl_table *t; |
| 3795 | const char *dev_name_source; |
| 3796 | char neigh_path[ sizeof("net//neigh/") + IFNAMSIZ + IFNAMSIZ ]; |
| 3797 | char *p_name; |
| 3798 | size_t neigh_vars_size; |
| 3799 | |
| 3800 | t = kmemdup(&neigh_sysctl_template, sizeof(*t), GFP_KERNEL_ACCOUNT); |
| 3801 | if (!t) |
| 3802 | goto err; |
| 3803 | |
| 3804 | for (i = 0; i < NEIGH_VAR_GC_INTERVAL; i++) { |
| 3805 | t->neigh_vars[i].data += (long) p; |
| 3806 | t->neigh_vars[i].extra1 = dev; |
| 3807 | t->neigh_vars[i].extra2 = p; |
| 3808 | } |
| 3809 | |
| 3810 | neigh_vars_size = ARRAY_SIZE(t->neigh_vars); |
| 3811 | if (dev) { |
| 3812 | dev_name_source = dev->name; |
| 3813 | /* Terminate the table early */ |
| 3814 | neigh_vars_size = NEIGH_VAR_BASE_REACHABLE_TIME_MS + 1; |
| 3815 | } else { |
| 3816 | struct neigh_table *tbl = p->tbl; |
| 3817 | dev_name_source = "default"; |
| 3818 | t->neigh_vars[NEIGH_VAR_GC_INTERVAL].data = &tbl->gc_interval; |
| 3819 | t->neigh_vars[NEIGH_VAR_GC_THRESH1].data = &tbl->gc_thresh1; |
| 3820 | t->neigh_vars[NEIGH_VAR_GC_THRESH2].data = &tbl->gc_thresh2; |
| 3821 | t->neigh_vars[NEIGH_VAR_GC_THRESH3].data = &tbl->gc_thresh3; |
| 3822 | } |
| 3823 | |
| 3824 | if (handler) { |
| 3825 | /* RetransTime */ |
| 3826 | t->neigh_vars[NEIGH_VAR_RETRANS_TIME].proc_handler = handler; |
| 3827 | /* ReachableTime */ |
| 3828 | t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME].proc_handler = handler; |
| 3829 | /* RetransTime (in milliseconds)*/ |
| 3830 | t->neigh_vars[NEIGH_VAR_RETRANS_TIME_MS].proc_handler = handler; |
| 3831 | /* ReachableTime (in milliseconds) */ |
| 3832 | t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME_MS].proc_handler = handler; |
| 3833 | } else { |
| 3834 | /* Those handlers will update p->reachable_time after |
| 3835 | * base_reachable_time(_ms) is set to ensure the new timer starts being |
| 3836 | * applied after the next neighbour update instead of waiting for |
| 3837 | * neigh_periodic_work to update its value (can be multiple minutes) |
| 3838 | * So any handler that replaces them should do this as well |
| 3839 | */ |
| 3840 | /* ReachableTime */ |
| 3841 | t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME].proc_handler = |
| 3842 | neigh_proc_base_reachable_time; |
| 3843 | /* ReachableTime (in milliseconds) */ |
| 3844 | t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME_MS].proc_handler = |
| 3845 | neigh_proc_base_reachable_time; |
| 3846 | } |
| 3847 | |
| 3848 | switch (neigh_parms_family(p)) { |
| 3849 | case AF_INET: |
| 3850 | p_name = "ipv4"; |
| 3851 | break; |
| 3852 | case AF_INET6: |
| 3853 | p_name = "ipv6"; |
| 3854 | break; |
| 3855 | default: |
| 3856 | BUG(); |
| 3857 | } |
| 3858 | |
| 3859 | snprintf(neigh_path, sizeof(neigh_path), "net/%s/neigh/%s", |
| 3860 | p_name, dev_name_source); |
| 3861 | t->sysctl_header = register_net_sysctl_sz(neigh_parms_net(p), |
| 3862 | neigh_path, t->neigh_vars, |
| 3863 | neigh_vars_size); |
| 3864 | if (!t->sysctl_header) |
| 3865 | goto free; |
| 3866 | |
| 3867 | p->sysctl_table = t; |
| 3868 | return 0; |
| 3869 | |
| 3870 | free: |
| 3871 | kfree(t); |
| 3872 | err: |
| 3873 | return -ENOBUFS; |
| 3874 | } |
| 3875 | EXPORT_SYMBOL(neigh_sysctl_register); |
| 3876 | |
| 3877 | void neigh_sysctl_unregister(struct neigh_parms *p) |
| 3878 | { |
| 3879 | if (p->sysctl_table) { |
| 3880 | struct neigh_sysctl_table *t = p->sysctl_table; |
| 3881 | p->sysctl_table = NULL; |
| 3882 | unregister_net_sysctl_table(t->sysctl_header); |
| 3883 | kfree(t); |
| 3884 | } |
| 3885 | } |
| 3886 | EXPORT_SYMBOL(neigh_sysctl_unregister); |
| 3887 | |
| 3888 | #endif /* CONFIG_SYSCTL */ |
| 3889 | |
| 3890 | static int __init neigh_init(void) |
| 3891 | { |
| 3892 | rtnl_register(PF_UNSPEC, RTM_NEWNEIGH, neigh_add, NULL, 0); |
| 3893 | rtnl_register(PF_UNSPEC, RTM_DELNEIGH, neigh_delete, NULL, 0); |
| 3894 | rtnl_register(PF_UNSPEC, RTM_GETNEIGH, neigh_get, neigh_dump_info, |
| 3895 | RTNL_FLAG_DUMP_UNLOCKED); |
| 3896 | |
| 3897 | rtnl_register(PF_UNSPEC, RTM_GETNEIGHTBL, NULL, neightbl_dump_info, |
| 3898 | 0); |
| 3899 | rtnl_register(PF_UNSPEC, RTM_SETNEIGHTBL, neightbl_set, NULL, 0); |
| 3900 | |
| 3901 | return 0; |
| 3902 | } |
| 3903 | |
| 3904 | subsys_initcall(neigh_init); |