originator.c 17 KB

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  1. /* Copyright (C) 2009-2012 B.A.T.M.A.N. contributors:
  2. *
  3. * Marek Lindner, Simon Wunderlich
  4. *
  5. * This program is free software; you can redistribute it and/or
  6. * modify it under the terms of version 2 of the GNU General Public
  7. * License as published by the Free Software Foundation.
  8. *
  9. * This program is distributed in the hope that it will be useful, but
  10. * WITHOUT ANY WARRANTY; without even the implied warranty of
  11. * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  12. * General Public License for more details.
  13. *
  14. * You should have received a copy of the GNU General Public License
  15. * along with this program; if not, write to the Free Software
  16. * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  17. * 02110-1301, USA
  18. */
  19. #include "main.h"
  20. #include "originator.h"
  21. #include "hash.h"
  22. #include "translation-table.h"
  23. #include "routing.h"
  24. #include "gateway_client.h"
  25. #include "hard-interface.h"
  26. #include "unicast.h"
  27. #include "soft-interface.h"
  28. #include "bridge_loop_avoidance.h"
  29. static void purge_orig(struct work_struct *work);
  30. static void start_purge_timer(struct bat_priv *bat_priv)
  31. {
  32. INIT_DELAYED_WORK(&bat_priv->orig_work, purge_orig);
  33. queue_delayed_work(batadv_event_workqueue,
  34. &bat_priv->orig_work, msecs_to_jiffies(1000));
  35. }
  36. /* returns 1 if they are the same originator */
  37. static int compare_orig(const struct hlist_node *node, const void *data2)
  38. {
  39. const void *data1 = container_of(node, struct orig_node, hash_entry);
  40. return (memcmp(data1, data2, ETH_ALEN) == 0 ? 1 : 0);
  41. }
  42. int batadv_originator_init(struct bat_priv *bat_priv)
  43. {
  44. if (bat_priv->orig_hash)
  45. return 0;
  46. bat_priv->orig_hash = batadv_hash_new(1024);
  47. if (!bat_priv->orig_hash)
  48. goto err;
  49. start_purge_timer(bat_priv);
  50. return 0;
  51. err:
  52. return -ENOMEM;
  53. }
  54. void batadv_neigh_node_free_ref(struct neigh_node *neigh_node)
  55. {
  56. if (atomic_dec_and_test(&neigh_node->refcount))
  57. kfree_rcu(neigh_node, rcu);
  58. }
  59. /* increases the refcounter of a found router */
  60. struct neigh_node *batadv_orig_node_get_router(struct orig_node *orig_node)
  61. {
  62. struct neigh_node *router;
  63. rcu_read_lock();
  64. router = rcu_dereference(orig_node->router);
  65. if (router && !atomic_inc_not_zero(&router->refcount))
  66. router = NULL;
  67. rcu_read_unlock();
  68. return router;
  69. }
  70. struct neigh_node *batadv_neigh_node_new(struct hard_iface *hard_iface,
  71. const uint8_t *neigh_addr,
  72. uint32_t seqno)
  73. {
  74. struct bat_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
  75. struct neigh_node *neigh_node;
  76. neigh_node = kzalloc(sizeof(*neigh_node), GFP_ATOMIC);
  77. if (!neigh_node)
  78. goto out;
  79. INIT_HLIST_NODE(&neigh_node->list);
  80. memcpy(neigh_node->addr, neigh_addr, ETH_ALEN);
  81. spin_lock_init(&neigh_node->lq_update_lock);
  82. /* extra reference for return */
  83. atomic_set(&neigh_node->refcount, 2);
  84. bat_dbg(DBG_BATMAN, bat_priv,
  85. "Creating new neighbor %pM, initial seqno %d\n",
  86. neigh_addr, seqno);
  87. out:
  88. return neigh_node;
  89. }
  90. static void orig_node_free_rcu(struct rcu_head *rcu)
  91. {
  92. struct hlist_node *node, *node_tmp;
  93. struct neigh_node *neigh_node, *tmp_neigh_node;
  94. struct orig_node *orig_node;
  95. orig_node = container_of(rcu, struct orig_node, rcu);
  96. spin_lock_bh(&orig_node->neigh_list_lock);
  97. /* for all bonding members ... */
  98. list_for_each_entry_safe(neigh_node, tmp_neigh_node,
  99. &orig_node->bond_list, bonding_list) {
  100. list_del_rcu(&neigh_node->bonding_list);
  101. batadv_neigh_node_free_ref(neigh_node);
  102. }
  103. /* for all neighbors towards this originator ... */
  104. hlist_for_each_entry_safe(neigh_node, node, node_tmp,
  105. &orig_node->neigh_list, list) {
  106. hlist_del_rcu(&neigh_node->list);
  107. batadv_neigh_node_free_ref(neigh_node);
  108. }
  109. spin_unlock_bh(&orig_node->neigh_list_lock);
  110. batadv_frag_list_free(&orig_node->frag_list);
  111. batadv_tt_global_del_orig(orig_node->bat_priv, orig_node,
  112. "originator timed out");
  113. kfree(orig_node->tt_buff);
  114. kfree(orig_node->bcast_own);
  115. kfree(orig_node->bcast_own_sum);
  116. kfree(orig_node);
  117. }
  118. void batadv_orig_node_free_ref(struct orig_node *orig_node)
  119. {
  120. if (atomic_dec_and_test(&orig_node->refcount))
  121. call_rcu(&orig_node->rcu, orig_node_free_rcu);
  122. }
  123. void batadv_originator_free(struct bat_priv *bat_priv)
  124. {
  125. struct hashtable_t *hash = bat_priv->orig_hash;
  126. struct hlist_node *node, *node_tmp;
  127. struct hlist_head *head;
  128. spinlock_t *list_lock; /* spinlock to protect write access */
  129. struct orig_node *orig_node;
  130. uint32_t i;
  131. if (!hash)
  132. return;
  133. cancel_delayed_work_sync(&bat_priv->orig_work);
  134. bat_priv->orig_hash = NULL;
  135. for (i = 0; i < hash->size; i++) {
  136. head = &hash->table[i];
  137. list_lock = &hash->list_locks[i];
  138. spin_lock_bh(list_lock);
  139. hlist_for_each_entry_safe(orig_node, node, node_tmp,
  140. head, hash_entry) {
  141. hlist_del_rcu(node);
  142. batadv_orig_node_free_ref(orig_node);
  143. }
  144. spin_unlock_bh(list_lock);
  145. }
  146. batadv_hash_destroy(hash);
  147. }
  148. /* this function finds or creates an originator entry for the given
  149. * address if it does not exits
  150. */
  151. struct orig_node *batadv_get_orig_node(struct bat_priv *bat_priv,
  152. const uint8_t *addr)
  153. {
  154. struct orig_node *orig_node;
  155. int size;
  156. int hash_added;
  157. orig_node = orig_hash_find(bat_priv, addr);
  158. if (orig_node)
  159. return orig_node;
  160. bat_dbg(DBG_BATMAN, bat_priv,
  161. "Creating new originator: %pM\n", addr);
  162. orig_node = kzalloc(sizeof(*orig_node), GFP_ATOMIC);
  163. if (!orig_node)
  164. return NULL;
  165. INIT_HLIST_HEAD(&orig_node->neigh_list);
  166. INIT_LIST_HEAD(&orig_node->bond_list);
  167. spin_lock_init(&orig_node->ogm_cnt_lock);
  168. spin_lock_init(&orig_node->bcast_seqno_lock);
  169. spin_lock_init(&orig_node->neigh_list_lock);
  170. spin_lock_init(&orig_node->tt_buff_lock);
  171. /* extra reference for return */
  172. atomic_set(&orig_node->refcount, 2);
  173. orig_node->tt_initialised = false;
  174. orig_node->tt_poss_change = false;
  175. orig_node->bat_priv = bat_priv;
  176. memcpy(orig_node->orig, addr, ETH_ALEN);
  177. orig_node->router = NULL;
  178. orig_node->tt_crc = 0;
  179. atomic_set(&orig_node->last_ttvn, 0);
  180. orig_node->tt_buff = NULL;
  181. orig_node->tt_buff_len = 0;
  182. atomic_set(&orig_node->tt_size, 0);
  183. orig_node->bcast_seqno_reset = jiffies - 1
  184. - msecs_to_jiffies(RESET_PROTECTION_MS);
  185. orig_node->batman_seqno_reset = jiffies - 1
  186. - msecs_to_jiffies(RESET_PROTECTION_MS);
  187. atomic_set(&orig_node->bond_candidates, 0);
  188. size = bat_priv->num_ifaces * sizeof(unsigned long) * NUM_WORDS;
  189. orig_node->bcast_own = kzalloc(size, GFP_ATOMIC);
  190. if (!orig_node->bcast_own)
  191. goto free_orig_node;
  192. size = bat_priv->num_ifaces * sizeof(uint8_t);
  193. orig_node->bcast_own_sum = kzalloc(size, GFP_ATOMIC);
  194. INIT_LIST_HEAD(&orig_node->frag_list);
  195. orig_node->last_frag_packet = 0;
  196. if (!orig_node->bcast_own_sum)
  197. goto free_bcast_own;
  198. hash_added = batadv_hash_add(bat_priv->orig_hash, compare_orig,
  199. choose_orig, orig_node,
  200. &orig_node->hash_entry);
  201. if (hash_added != 0)
  202. goto free_bcast_own_sum;
  203. return orig_node;
  204. free_bcast_own_sum:
  205. kfree(orig_node->bcast_own_sum);
  206. free_bcast_own:
  207. kfree(orig_node->bcast_own);
  208. free_orig_node:
  209. kfree(orig_node);
  210. return NULL;
  211. }
  212. static bool purge_orig_neighbors(struct bat_priv *bat_priv,
  213. struct orig_node *orig_node,
  214. struct neigh_node **best_neigh_node)
  215. {
  216. struct hlist_node *node, *node_tmp;
  217. struct neigh_node *neigh_node;
  218. bool neigh_purged = false;
  219. unsigned long last_seen;
  220. *best_neigh_node = NULL;
  221. spin_lock_bh(&orig_node->neigh_list_lock);
  222. /* for all neighbors towards this originator ... */
  223. hlist_for_each_entry_safe(neigh_node, node, node_tmp,
  224. &orig_node->neigh_list, list) {
  225. if ((has_timed_out(neigh_node->last_seen, PURGE_TIMEOUT)) ||
  226. (neigh_node->if_incoming->if_status == IF_INACTIVE) ||
  227. (neigh_node->if_incoming->if_status == IF_NOT_IN_USE) ||
  228. (neigh_node->if_incoming->if_status == IF_TO_BE_REMOVED)) {
  229. last_seen = neigh_node->last_seen;
  230. if ((neigh_node->if_incoming->if_status ==
  231. IF_INACTIVE) ||
  232. (neigh_node->if_incoming->if_status ==
  233. IF_NOT_IN_USE) ||
  234. (neigh_node->if_incoming->if_status ==
  235. IF_TO_BE_REMOVED))
  236. bat_dbg(DBG_BATMAN, bat_priv,
  237. "neighbor purge: originator %pM, neighbor: %pM, iface: %s\n",
  238. orig_node->orig, neigh_node->addr,
  239. neigh_node->if_incoming->net_dev->name);
  240. else
  241. bat_dbg(DBG_BATMAN, bat_priv,
  242. "neighbor timeout: originator %pM, neighbor: %pM, last_seen: %u\n",
  243. orig_node->orig, neigh_node->addr,
  244. jiffies_to_msecs(last_seen));
  245. neigh_purged = true;
  246. hlist_del_rcu(&neigh_node->list);
  247. batadv_bonding_candidate_del(orig_node, neigh_node);
  248. batadv_neigh_node_free_ref(neigh_node);
  249. } else {
  250. if ((!*best_neigh_node) ||
  251. (neigh_node->tq_avg > (*best_neigh_node)->tq_avg))
  252. *best_neigh_node = neigh_node;
  253. }
  254. }
  255. spin_unlock_bh(&orig_node->neigh_list_lock);
  256. return neigh_purged;
  257. }
  258. static bool purge_orig_node(struct bat_priv *bat_priv,
  259. struct orig_node *orig_node)
  260. {
  261. struct neigh_node *best_neigh_node;
  262. if (has_timed_out(orig_node->last_seen, 2 * PURGE_TIMEOUT)) {
  263. bat_dbg(DBG_BATMAN, bat_priv,
  264. "Originator timeout: originator %pM, last_seen %u\n",
  265. orig_node->orig,
  266. jiffies_to_msecs(orig_node->last_seen));
  267. return true;
  268. } else {
  269. if (purge_orig_neighbors(bat_priv, orig_node,
  270. &best_neigh_node))
  271. batadv_update_route(bat_priv, orig_node,
  272. best_neigh_node);
  273. }
  274. return false;
  275. }
  276. static void _purge_orig(struct bat_priv *bat_priv)
  277. {
  278. struct hashtable_t *hash = bat_priv->orig_hash;
  279. struct hlist_node *node, *node_tmp;
  280. struct hlist_head *head;
  281. spinlock_t *list_lock; /* spinlock to protect write access */
  282. struct orig_node *orig_node;
  283. uint32_t i;
  284. if (!hash)
  285. return;
  286. /* for all origins... */
  287. for (i = 0; i < hash->size; i++) {
  288. head = &hash->table[i];
  289. list_lock = &hash->list_locks[i];
  290. spin_lock_bh(list_lock);
  291. hlist_for_each_entry_safe(orig_node, node, node_tmp,
  292. head, hash_entry) {
  293. if (purge_orig_node(bat_priv, orig_node)) {
  294. if (orig_node->gw_flags)
  295. batadv_gw_node_delete(bat_priv,
  296. orig_node);
  297. hlist_del_rcu(node);
  298. batadv_orig_node_free_ref(orig_node);
  299. continue;
  300. }
  301. if (has_timed_out(orig_node->last_frag_packet,
  302. FRAG_TIMEOUT))
  303. batadv_frag_list_free(&orig_node->frag_list);
  304. }
  305. spin_unlock_bh(list_lock);
  306. }
  307. batadv_gw_node_purge(bat_priv);
  308. batadv_gw_election(bat_priv);
  309. }
  310. static void purge_orig(struct work_struct *work)
  311. {
  312. struct delayed_work *delayed_work =
  313. container_of(work, struct delayed_work, work);
  314. struct bat_priv *bat_priv =
  315. container_of(delayed_work, struct bat_priv, orig_work);
  316. _purge_orig(bat_priv);
  317. start_purge_timer(bat_priv);
  318. }
  319. void batadv_purge_orig_ref(struct bat_priv *bat_priv)
  320. {
  321. _purge_orig(bat_priv);
  322. }
  323. int batadv_orig_seq_print_text(struct seq_file *seq, void *offset)
  324. {
  325. struct net_device *net_dev = (struct net_device *)seq->private;
  326. struct bat_priv *bat_priv = netdev_priv(net_dev);
  327. struct hashtable_t *hash = bat_priv->orig_hash;
  328. struct hlist_node *node, *node_tmp;
  329. struct hlist_head *head;
  330. struct hard_iface *primary_if;
  331. struct orig_node *orig_node;
  332. struct neigh_node *neigh_node, *neigh_node_tmp;
  333. int batman_count = 0;
  334. int last_seen_secs;
  335. int last_seen_msecs;
  336. uint32_t i;
  337. int ret = 0;
  338. primary_if = batadv_primary_if_get_selected(bat_priv);
  339. if (!primary_if) {
  340. ret = seq_printf(seq,
  341. "BATMAN mesh %s disabled - please specify interfaces to enable it\n",
  342. net_dev->name);
  343. goto out;
  344. }
  345. if (primary_if->if_status != IF_ACTIVE) {
  346. ret = seq_printf(seq,
  347. "BATMAN mesh %s disabled - primary interface not active\n",
  348. net_dev->name);
  349. goto out;
  350. }
  351. seq_printf(seq, "[B.A.T.M.A.N. adv %s, MainIF/MAC: %s/%pM (%s)]\n",
  352. SOURCE_VERSION, primary_if->net_dev->name,
  353. primary_if->net_dev->dev_addr, net_dev->name);
  354. seq_printf(seq, " %-15s %s (%s/%i) %17s [%10s]: %20s ...\n",
  355. "Originator", "last-seen", "#", TQ_MAX_VALUE, "Nexthop",
  356. "outgoingIF", "Potential nexthops");
  357. for (i = 0; i < hash->size; i++) {
  358. head = &hash->table[i];
  359. rcu_read_lock();
  360. hlist_for_each_entry_rcu(orig_node, node, head, hash_entry) {
  361. neigh_node = batadv_orig_node_get_router(orig_node);
  362. if (!neigh_node)
  363. continue;
  364. if (neigh_node->tq_avg == 0)
  365. goto next;
  366. last_seen_secs = jiffies_to_msecs(jiffies -
  367. orig_node->last_seen) / 1000;
  368. last_seen_msecs = jiffies_to_msecs(jiffies -
  369. orig_node->last_seen) % 1000;
  370. seq_printf(seq, "%pM %4i.%03is (%3i) %pM [%10s]:",
  371. orig_node->orig, last_seen_secs,
  372. last_seen_msecs, neigh_node->tq_avg,
  373. neigh_node->addr,
  374. neigh_node->if_incoming->net_dev->name);
  375. hlist_for_each_entry_rcu(neigh_node_tmp, node_tmp,
  376. &orig_node->neigh_list, list) {
  377. seq_printf(seq, " %pM (%3i)",
  378. neigh_node_tmp->addr,
  379. neigh_node_tmp->tq_avg);
  380. }
  381. seq_printf(seq, "\n");
  382. batman_count++;
  383. next:
  384. batadv_neigh_node_free_ref(neigh_node);
  385. }
  386. rcu_read_unlock();
  387. }
  388. if (batman_count == 0)
  389. seq_printf(seq, "No batman nodes in range ...\n");
  390. out:
  391. if (primary_if)
  392. batadv_hardif_free_ref(primary_if);
  393. return ret;
  394. }
  395. static int orig_node_add_if(struct orig_node *orig_node, int max_if_num)
  396. {
  397. void *data_ptr;
  398. data_ptr = kmalloc(max_if_num * sizeof(unsigned long) * NUM_WORDS,
  399. GFP_ATOMIC);
  400. if (!data_ptr)
  401. return -ENOMEM;
  402. memcpy(data_ptr, orig_node->bcast_own,
  403. (max_if_num - 1) * sizeof(unsigned long) * NUM_WORDS);
  404. kfree(orig_node->bcast_own);
  405. orig_node->bcast_own = data_ptr;
  406. data_ptr = kmalloc(max_if_num * sizeof(uint8_t), GFP_ATOMIC);
  407. if (!data_ptr)
  408. return -ENOMEM;
  409. memcpy(data_ptr, orig_node->bcast_own_sum,
  410. (max_if_num - 1) * sizeof(uint8_t));
  411. kfree(orig_node->bcast_own_sum);
  412. orig_node->bcast_own_sum = data_ptr;
  413. return 0;
  414. }
  415. int batadv_orig_hash_add_if(struct hard_iface *hard_iface, int max_if_num)
  416. {
  417. struct bat_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
  418. struct hashtable_t *hash = bat_priv->orig_hash;
  419. struct hlist_node *node;
  420. struct hlist_head *head;
  421. struct orig_node *orig_node;
  422. uint32_t i;
  423. int ret;
  424. /* resize all orig nodes because orig_node->bcast_own(_sum) depend on
  425. * if_num
  426. */
  427. for (i = 0; i < hash->size; i++) {
  428. head = &hash->table[i];
  429. rcu_read_lock();
  430. hlist_for_each_entry_rcu(orig_node, node, head, hash_entry) {
  431. spin_lock_bh(&orig_node->ogm_cnt_lock);
  432. ret = orig_node_add_if(orig_node, max_if_num);
  433. spin_unlock_bh(&orig_node->ogm_cnt_lock);
  434. if (ret == -ENOMEM)
  435. goto err;
  436. }
  437. rcu_read_unlock();
  438. }
  439. return 0;
  440. err:
  441. rcu_read_unlock();
  442. return -ENOMEM;
  443. }
  444. static int orig_node_del_if(struct orig_node *orig_node,
  445. int max_if_num, int del_if_num)
  446. {
  447. void *data_ptr = NULL;
  448. int chunk_size;
  449. /* last interface was removed */
  450. if (max_if_num == 0)
  451. goto free_bcast_own;
  452. chunk_size = sizeof(unsigned long) * NUM_WORDS;
  453. data_ptr = kmalloc(max_if_num * chunk_size, GFP_ATOMIC);
  454. if (!data_ptr)
  455. return -ENOMEM;
  456. /* copy first part */
  457. memcpy(data_ptr, orig_node->bcast_own, del_if_num * chunk_size);
  458. /* copy second part */
  459. memcpy((char *)data_ptr + del_if_num * chunk_size,
  460. orig_node->bcast_own + ((del_if_num + 1) * chunk_size),
  461. (max_if_num - del_if_num) * chunk_size);
  462. free_bcast_own:
  463. kfree(orig_node->bcast_own);
  464. orig_node->bcast_own = data_ptr;
  465. if (max_if_num == 0)
  466. goto free_own_sum;
  467. data_ptr = kmalloc(max_if_num * sizeof(uint8_t), GFP_ATOMIC);
  468. if (!data_ptr)
  469. return -ENOMEM;
  470. memcpy(data_ptr, orig_node->bcast_own_sum,
  471. del_if_num * sizeof(uint8_t));
  472. memcpy((char *)data_ptr + del_if_num * sizeof(uint8_t),
  473. orig_node->bcast_own_sum + ((del_if_num + 1) * sizeof(uint8_t)),
  474. (max_if_num - del_if_num) * sizeof(uint8_t));
  475. free_own_sum:
  476. kfree(orig_node->bcast_own_sum);
  477. orig_node->bcast_own_sum = data_ptr;
  478. return 0;
  479. }
  480. int batadv_orig_hash_del_if(struct hard_iface *hard_iface, int max_if_num)
  481. {
  482. struct bat_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
  483. struct hashtable_t *hash = bat_priv->orig_hash;
  484. struct hlist_node *node;
  485. struct hlist_head *head;
  486. struct hard_iface *hard_iface_tmp;
  487. struct orig_node *orig_node;
  488. uint32_t i;
  489. int ret;
  490. /* resize all orig nodes because orig_node->bcast_own(_sum) depend on
  491. * if_num
  492. */
  493. for (i = 0; i < hash->size; i++) {
  494. head = &hash->table[i];
  495. rcu_read_lock();
  496. hlist_for_each_entry_rcu(orig_node, node, head, hash_entry) {
  497. spin_lock_bh(&orig_node->ogm_cnt_lock);
  498. ret = orig_node_del_if(orig_node, max_if_num,
  499. hard_iface->if_num);
  500. spin_unlock_bh(&orig_node->ogm_cnt_lock);
  501. if (ret == -ENOMEM)
  502. goto err;
  503. }
  504. rcu_read_unlock();
  505. }
  506. /* renumber remaining batman interfaces _inside_ of orig_hash_lock */
  507. rcu_read_lock();
  508. list_for_each_entry_rcu(hard_iface_tmp, &batadv_hardif_list, list) {
  509. if (hard_iface_tmp->if_status == IF_NOT_IN_USE)
  510. continue;
  511. if (hard_iface == hard_iface_tmp)
  512. continue;
  513. if (hard_iface->soft_iface != hard_iface_tmp->soft_iface)
  514. continue;
  515. if (hard_iface_tmp->if_num > hard_iface->if_num)
  516. hard_iface_tmp->if_num--;
  517. }
  518. rcu_read_unlock();
  519. hard_iface->if_num = -1;
  520. return 0;
  521. err:
  522. rcu_read_unlock();
  523. return -ENOMEM;
  524. }