br_multicast.c 44 KB

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  1. /*
  2. * Bridge multicast support.
  3. *
  4. * Copyright (c) 2010 Herbert Xu <herbert@gondor.apana.org.au>
  5. *
  6. * This program is free software; you can redistribute it and/or modify it
  7. * under the terms of the GNU General Public License as published by the Free
  8. * Software Foundation; either version 2 of the License, or (at your option)
  9. * any later version.
  10. *
  11. */
  12. #include <linux/err.h>
  13. #include <linux/if_ether.h>
  14. #include <linux/igmp.h>
  15. #include <linux/jhash.h>
  16. #include <linux/kernel.h>
  17. #include <linux/log2.h>
  18. #include <linux/netdevice.h>
  19. #include <linux/netfilter_bridge.h>
  20. #include <linux/random.h>
  21. #include <linux/rculist.h>
  22. #include <linux/skbuff.h>
  23. #include <linux/slab.h>
  24. #include <linux/timer.h>
  25. #include <linux/inetdevice.h>
  26. #include <net/ip.h>
  27. #if IS_ENABLED(CONFIG_IPV6)
  28. #include <net/ipv6.h>
  29. #include <net/mld.h>
  30. #include <net/ip6_checksum.h>
  31. #include <net/addrconf.h>
  32. #endif
  33. #include "br_private.h"
  34. static void br_multicast_start_querier(struct net_bridge *br,
  35. struct bridge_mcast_query *query);
  36. unsigned int br_mdb_rehash_seq;
  37. static inline int br_ip_equal(const struct br_ip *a, const struct br_ip *b)
  38. {
  39. if (a->proto != b->proto)
  40. return 0;
  41. if (a->vid != b->vid)
  42. return 0;
  43. switch (a->proto) {
  44. case htons(ETH_P_IP):
  45. return a->u.ip4 == b->u.ip4;
  46. #if IS_ENABLED(CONFIG_IPV6)
  47. case htons(ETH_P_IPV6):
  48. return ipv6_addr_equal(&a->u.ip6, &b->u.ip6);
  49. #endif
  50. }
  51. return 0;
  52. }
  53. static inline int __br_ip4_hash(struct net_bridge_mdb_htable *mdb, __be32 ip,
  54. __u16 vid)
  55. {
  56. return jhash_2words((__force u32)ip, vid, mdb->secret) & (mdb->max - 1);
  57. }
  58. #if IS_ENABLED(CONFIG_IPV6)
  59. static inline int __br_ip6_hash(struct net_bridge_mdb_htable *mdb,
  60. const struct in6_addr *ip,
  61. __u16 vid)
  62. {
  63. return jhash_2words(ipv6_addr_hash(ip), vid,
  64. mdb->secret) & (mdb->max - 1);
  65. }
  66. #endif
  67. static inline int br_ip_hash(struct net_bridge_mdb_htable *mdb,
  68. struct br_ip *ip)
  69. {
  70. switch (ip->proto) {
  71. case htons(ETH_P_IP):
  72. return __br_ip4_hash(mdb, ip->u.ip4, ip->vid);
  73. #if IS_ENABLED(CONFIG_IPV6)
  74. case htons(ETH_P_IPV6):
  75. return __br_ip6_hash(mdb, &ip->u.ip6, ip->vid);
  76. #endif
  77. }
  78. return 0;
  79. }
  80. static struct net_bridge_mdb_entry *__br_mdb_ip_get(
  81. struct net_bridge_mdb_htable *mdb, struct br_ip *dst, int hash)
  82. {
  83. struct net_bridge_mdb_entry *mp;
  84. hlist_for_each_entry_rcu(mp, &mdb->mhash[hash], hlist[mdb->ver]) {
  85. if (br_ip_equal(&mp->addr, dst))
  86. return mp;
  87. }
  88. return NULL;
  89. }
  90. struct net_bridge_mdb_entry *br_mdb_ip_get(struct net_bridge_mdb_htable *mdb,
  91. struct br_ip *dst)
  92. {
  93. if (!mdb)
  94. return NULL;
  95. return __br_mdb_ip_get(mdb, dst, br_ip_hash(mdb, dst));
  96. }
  97. static struct net_bridge_mdb_entry *br_mdb_ip4_get(
  98. struct net_bridge_mdb_htable *mdb, __be32 dst, __u16 vid)
  99. {
  100. struct br_ip br_dst;
  101. br_dst.u.ip4 = dst;
  102. br_dst.proto = htons(ETH_P_IP);
  103. br_dst.vid = vid;
  104. return br_mdb_ip_get(mdb, &br_dst);
  105. }
  106. #if IS_ENABLED(CONFIG_IPV6)
  107. static struct net_bridge_mdb_entry *br_mdb_ip6_get(
  108. struct net_bridge_mdb_htable *mdb, const struct in6_addr *dst,
  109. __u16 vid)
  110. {
  111. struct br_ip br_dst;
  112. br_dst.u.ip6 = *dst;
  113. br_dst.proto = htons(ETH_P_IPV6);
  114. br_dst.vid = vid;
  115. return br_mdb_ip_get(mdb, &br_dst);
  116. }
  117. #endif
  118. struct net_bridge_mdb_entry *br_mdb_get(struct net_bridge *br,
  119. struct sk_buff *skb, u16 vid)
  120. {
  121. struct net_bridge_mdb_htable *mdb = rcu_dereference(br->mdb);
  122. struct br_ip ip;
  123. if (br->multicast_disabled)
  124. return NULL;
  125. if (BR_INPUT_SKB_CB(skb)->igmp)
  126. return NULL;
  127. ip.proto = skb->protocol;
  128. ip.vid = vid;
  129. switch (skb->protocol) {
  130. case htons(ETH_P_IP):
  131. ip.u.ip4 = ip_hdr(skb)->daddr;
  132. break;
  133. #if IS_ENABLED(CONFIG_IPV6)
  134. case htons(ETH_P_IPV6):
  135. ip.u.ip6 = ipv6_hdr(skb)->daddr;
  136. break;
  137. #endif
  138. default:
  139. return NULL;
  140. }
  141. return br_mdb_ip_get(mdb, &ip);
  142. }
  143. static void br_mdb_free(struct rcu_head *head)
  144. {
  145. struct net_bridge_mdb_htable *mdb =
  146. container_of(head, struct net_bridge_mdb_htable, rcu);
  147. struct net_bridge_mdb_htable *old = mdb->old;
  148. mdb->old = NULL;
  149. kfree(old->mhash);
  150. kfree(old);
  151. }
  152. static int br_mdb_copy(struct net_bridge_mdb_htable *new,
  153. struct net_bridge_mdb_htable *old,
  154. int elasticity)
  155. {
  156. struct net_bridge_mdb_entry *mp;
  157. int maxlen;
  158. int len;
  159. int i;
  160. for (i = 0; i < old->max; i++)
  161. hlist_for_each_entry(mp, &old->mhash[i], hlist[old->ver])
  162. hlist_add_head(&mp->hlist[new->ver],
  163. &new->mhash[br_ip_hash(new, &mp->addr)]);
  164. if (!elasticity)
  165. return 0;
  166. maxlen = 0;
  167. for (i = 0; i < new->max; i++) {
  168. len = 0;
  169. hlist_for_each_entry(mp, &new->mhash[i], hlist[new->ver])
  170. len++;
  171. if (len > maxlen)
  172. maxlen = len;
  173. }
  174. return maxlen > elasticity ? -EINVAL : 0;
  175. }
  176. void br_multicast_free_pg(struct rcu_head *head)
  177. {
  178. struct net_bridge_port_group *p =
  179. container_of(head, struct net_bridge_port_group, rcu);
  180. kfree(p);
  181. }
  182. static void br_multicast_free_group(struct rcu_head *head)
  183. {
  184. struct net_bridge_mdb_entry *mp =
  185. container_of(head, struct net_bridge_mdb_entry, rcu);
  186. kfree(mp);
  187. }
  188. static void br_multicast_group_expired(unsigned long data)
  189. {
  190. struct net_bridge_mdb_entry *mp = (void *)data;
  191. struct net_bridge *br = mp->br;
  192. struct net_bridge_mdb_htable *mdb;
  193. spin_lock(&br->multicast_lock);
  194. if (!netif_running(br->dev) || timer_pending(&mp->timer))
  195. goto out;
  196. mp->mglist = false;
  197. if (mp->ports)
  198. goto out;
  199. mdb = mlock_dereference(br->mdb, br);
  200. hlist_del_rcu(&mp->hlist[mdb->ver]);
  201. mdb->size--;
  202. call_rcu_bh(&mp->rcu, br_multicast_free_group);
  203. out:
  204. spin_unlock(&br->multicast_lock);
  205. }
  206. static void br_multicast_del_pg(struct net_bridge *br,
  207. struct net_bridge_port_group *pg)
  208. {
  209. struct net_bridge_mdb_htable *mdb;
  210. struct net_bridge_mdb_entry *mp;
  211. struct net_bridge_port_group *p;
  212. struct net_bridge_port_group __rcu **pp;
  213. mdb = mlock_dereference(br->mdb, br);
  214. mp = br_mdb_ip_get(mdb, &pg->addr);
  215. if (WARN_ON(!mp))
  216. return;
  217. for (pp = &mp->ports;
  218. (p = mlock_dereference(*pp, br)) != NULL;
  219. pp = &p->next) {
  220. if (p != pg)
  221. continue;
  222. rcu_assign_pointer(*pp, p->next);
  223. hlist_del_init(&p->mglist);
  224. del_timer(&p->timer);
  225. call_rcu_bh(&p->rcu, br_multicast_free_pg);
  226. if (!mp->ports && !mp->mglist &&
  227. netif_running(br->dev))
  228. mod_timer(&mp->timer, jiffies);
  229. return;
  230. }
  231. WARN_ON(1);
  232. }
  233. static void br_multicast_port_group_expired(unsigned long data)
  234. {
  235. struct net_bridge_port_group *pg = (void *)data;
  236. struct net_bridge *br = pg->port->br;
  237. spin_lock(&br->multicast_lock);
  238. if (!netif_running(br->dev) || timer_pending(&pg->timer) ||
  239. hlist_unhashed(&pg->mglist) || pg->state & MDB_PERMANENT)
  240. goto out;
  241. br_multicast_del_pg(br, pg);
  242. out:
  243. spin_unlock(&br->multicast_lock);
  244. }
  245. static int br_mdb_rehash(struct net_bridge_mdb_htable __rcu **mdbp, int max,
  246. int elasticity)
  247. {
  248. struct net_bridge_mdb_htable *old = rcu_dereference_protected(*mdbp, 1);
  249. struct net_bridge_mdb_htable *mdb;
  250. int err;
  251. mdb = kmalloc(sizeof(*mdb), GFP_ATOMIC);
  252. if (!mdb)
  253. return -ENOMEM;
  254. mdb->max = max;
  255. mdb->old = old;
  256. mdb->mhash = kzalloc(max * sizeof(*mdb->mhash), GFP_ATOMIC);
  257. if (!mdb->mhash) {
  258. kfree(mdb);
  259. return -ENOMEM;
  260. }
  261. mdb->size = old ? old->size : 0;
  262. mdb->ver = old ? old->ver ^ 1 : 0;
  263. if (!old || elasticity)
  264. get_random_bytes(&mdb->secret, sizeof(mdb->secret));
  265. else
  266. mdb->secret = old->secret;
  267. if (!old)
  268. goto out;
  269. err = br_mdb_copy(mdb, old, elasticity);
  270. if (err) {
  271. kfree(mdb->mhash);
  272. kfree(mdb);
  273. return err;
  274. }
  275. br_mdb_rehash_seq++;
  276. call_rcu_bh(&mdb->rcu, br_mdb_free);
  277. out:
  278. rcu_assign_pointer(*mdbp, mdb);
  279. return 0;
  280. }
  281. static struct sk_buff *br_ip4_multicast_alloc_query(struct net_bridge *br,
  282. __be32 group)
  283. {
  284. struct sk_buff *skb;
  285. struct igmphdr *ih;
  286. struct ethhdr *eth;
  287. struct iphdr *iph;
  288. skb = netdev_alloc_skb_ip_align(br->dev, sizeof(*eth) + sizeof(*iph) +
  289. sizeof(*ih) + 4);
  290. if (!skb)
  291. goto out;
  292. skb->protocol = htons(ETH_P_IP);
  293. skb_reset_mac_header(skb);
  294. eth = eth_hdr(skb);
  295. memcpy(eth->h_source, br->dev->dev_addr, ETH_ALEN);
  296. eth->h_dest[0] = 1;
  297. eth->h_dest[1] = 0;
  298. eth->h_dest[2] = 0x5e;
  299. eth->h_dest[3] = 0;
  300. eth->h_dest[4] = 0;
  301. eth->h_dest[5] = 1;
  302. eth->h_proto = htons(ETH_P_IP);
  303. skb_put(skb, sizeof(*eth));
  304. skb_set_network_header(skb, skb->len);
  305. iph = ip_hdr(skb);
  306. iph->version = 4;
  307. iph->ihl = 6;
  308. iph->tos = 0xc0;
  309. iph->tot_len = htons(sizeof(*iph) + sizeof(*ih) + 4);
  310. iph->id = 0;
  311. iph->frag_off = htons(IP_DF);
  312. iph->ttl = 1;
  313. iph->protocol = IPPROTO_IGMP;
  314. iph->saddr = br->multicast_query_use_ifaddr ?
  315. inet_select_addr(br->dev, 0, RT_SCOPE_LINK) : 0;
  316. iph->daddr = htonl(INADDR_ALLHOSTS_GROUP);
  317. ((u8 *)&iph[1])[0] = IPOPT_RA;
  318. ((u8 *)&iph[1])[1] = 4;
  319. ((u8 *)&iph[1])[2] = 0;
  320. ((u8 *)&iph[1])[3] = 0;
  321. ip_send_check(iph);
  322. skb_put(skb, 24);
  323. skb_set_transport_header(skb, skb->len);
  324. ih = igmp_hdr(skb);
  325. ih->type = IGMP_HOST_MEMBERSHIP_QUERY;
  326. ih->code = (group ? br->multicast_last_member_interval :
  327. br->multicast_query_response_interval) /
  328. (HZ / IGMP_TIMER_SCALE);
  329. ih->group = group;
  330. ih->csum = 0;
  331. ih->csum = ip_compute_csum((void *)ih, sizeof(struct igmphdr));
  332. skb_put(skb, sizeof(*ih));
  333. __skb_pull(skb, sizeof(*eth));
  334. out:
  335. return skb;
  336. }
  337. #if IS_ENABLED(CONFIG_IPV6)
  338. static struct sk_buff *br_ip6_multicast_alloc_query(struct net_bridge *br,
  339. const struct in6_addr *group)
  340. {
  341. struct sk_buff *skb;
  342. struct ipv6hdr *ip6h;
  343. struct mld_msg *mldq;
  344. struct ethhdr *eth;
  345. u8 *hopopt;
  346. unsigned long interval;
  347. skb = netdev_alloc_skb_ip_align(br->dev, sizeof(*eth) + sizeof(*ip6h) +
  348. 8 + sizeof(*mldq));
  349. if (!skb)
  350. goto out;
  351. skb->protocol = htons(ETH_P_IPV6);
  352. /* Ethernet header */
  353. skb_reset_mac_header(skb);
  354. eth = eth_hdr(skb);
  355. memcpy(eth->h_source, br->dev->dev_addr, ETH_ALEN);
  356. eth->h_proto = htons(ETH_P_IPV6);
  357. skb_put(skb, sizeof(*eth));
  358. /* IPv6 header + HbH option */
  359. skb_set_network_header(skb, skb->len);
  360. ip6h = ipv6_hdr(skb);
  361. *(__force __be32 *)ip6h = htonl(0x60000000);
  362. ip6h->payload_len = htons(8 + sizeof(*mldq));
  363. ip6h->nexthdr = IPPROTO_HOPOPTS;
  364. ip6h->hop_limit = 1;
  365. ipv6_addr_set(&ip6h->daddr, htonl(0xff020000), 0, 0, htonl(1));
  366. if (ipv6_dev_get_saddr(dev_net(br->dev), br->dev, &ip6h->daddr, 0,
  367. &ip6h->saddr)) {
  368. kfree_skb(skb);
  369. return NULL;
  370. }
  371. ipv6_eth_mc_map(&ip6h->daddr, eth->h_dest);
  372. hopopt = (u8 *)(ip6h + 1);
  373. hopopt[0] = IPPROTO_ICMPV6; /* next hdr */
  374. hopopt[1] = 0; /* length of HbH */
  375. hopopt[2] = IPV6_TLV_ROUTERALERT; /* Router Alert */
  376. hopopt[3] = 2; /* Length of RA Option */
  377. hopopt[4] = 0; /* Type = 0x0000 (MLD) */
  378. hopopt[5] = 0;
  379. hopopt[6] = IPV6_TLV_PAD1; /* Pad1 */
  380. hopopt[7] = IPV6_TLV_PAD1; /* Pad1 */
  381. skb_put(skb, sizeof(*ip6h) + 8);
  382. /* ICMPv6 */
  383. skb_set_transport_header(skb, skb->len);
  384. mldq = (struct mld_msg *) icmp6_hdr(skb);
  385. interval = ipv6_addr_any(group) ?
  386. br->multicast_query_response_interval :
  387. br->multicast_last_member_interval;
  388. mldq->mld_type = ICMPV6_MGM_QUERY;
  389. mldq->mld_code = 0;
  390. mldq->mld_cksum = 0;
  391. mldq->mld_maxdelay = htons((u16)jiffies_to_msecs(interval));
  392. mldq->mld_reserved = 0;
  393. mldq->mld_mca = *group;
  394. /* checksum */
  395. mldq->mld_cksum = csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
  396. sizeof(*mldq), IPPROTO_ICMPV6,
  397. csum_partial(mldq,
  398. sizeof(*mldq), 0));
  399. skb_put(skb, sizeof(*mldq));
  400. __skb_pull(skb, sizeof(*eth));
  401. out:
  402. return skb;
  403. }
  404. #endif
  405. static struct sk_buff *br_multicast_alloc_query(struct net_bridge *br,
  406. struct br_ip *addr)
  407. {
  408. switch (addr->proto) {
  409. case htons(ETH_P_IP):
  410. return br_ip4_multicast_alloc_query(br, addr->u.ip4);
  411. #if IS_ENABLED(CONFIG_IPV6)
  412. case htons(ETH_P_IPV6):
  413. return br_ip6_multicast_alloc_query(br, &addr->u.ip6);
  414. #endif
  415. }
  416. return NULL;
  417. }
  418. static struct net_bridge_mdb_entry *br_multicast_get_group(
  419. struct net_bridge *br, struct net_bridge_port *port,
  420. struct br_ip *group, int hash)
  421. {
  422. struct net_bridge_mdb_htable *mdb;
  423. struct net_bridge_mdb_entry *mp;
  424. unsigned int count = 0;
  425. unsigned int max;
  426. int elasticity;
  427. int err;
  428. mdb = rcu_dereference_protected(br->mdb, 1);
  429. hlist_for_each_entry(mp, &mdb->mhash[hash], hlist[mdb->ver]) {
  430. count++;
  431. if (unlikely(br_ip_equal(group, &mp->addr)))
  432. return mp;
  433. }
  434. elasticity = 0;
  435. max = mdb->max;
  436. if (unlikely(count > br->hash_elasticity && count)) {
  437. if (net_ratelimit())
  438. br_info(br, "Multicast hash table "
  439. "chain limit reached: %s\n",
  440. port ? port->dev->name : br->dev->name);
  441. elasticity = br->hash_elasticity;
  442. }
  443. if (mdb->size >= max) {
  444. max *= 2;
  445. if (unlikely(max > br->hash_max)) {
  446. br_warn(br, "Multicast hash table maximum of %d "
  447. "reached, disabling snooping: %s\n",
  448. br->hash_max,
  449. port ? port->dev->name : br->dev->name);
  450. err = -E2BIG;
  451. disable:
  452. br->multicast_disabled = 1;
  453. goto err;
  454. }
  455. }
  456. if (max > mdb->max || elasticity) {
  457. if (mdb->old) {
  458. if (net_ratelimit())
  459. br_info(br, "Multicast hash table "
  460. "on fire: %s\n",
  461. port ? port->dev->name : br->dev->name);
  462. err = -EEXIST;
  463. goto err;
  464. }
  465. err = br_mdb_rehash(&br->mdb, max, elasticity);
  466. if (err) {
  467. br_warn(br, "Cannot rehash multicast "
  468. "hash table, disabling snooping: %s, %d, %d\n",
  469. port ? port->dev->name : br->dev->name,
  470. mdb->size, err);
  471. goto disable;
  472. }
  473. err = -EAGAIN;
  474. goto err;
  475. }
  476. return NULL;
  477. err:
  478. mp = ERR_PTR(err);
  479. return mp;
  480. }
  481. struct net_bridge_mdb_entry *br_multicast_new_group(struct net_bridge *br,
  482. struct net_bridge_port *port, struct br_ip *group)
  483. {
  484. struct net_bridge_mdb_htable *mdb;
  485. struct net_bridge_mdb_entry *mp;
  486. int hash;
  487. int err;
  488. mdb = rcu_dereference_protected(br->mdb, 1);
  489. if (!mdb) {
  490. err = br_mdb_rehash(&br->mdb, BR_HASH_SIZE, 0);
  491. if (err)
  492. return ERR_PTR(err);
  493. goto rehash;
  494. }
  495. hash = br_ip_hash(mdb, group);
  496. mp = br_multicast_get_group(br, port, group, hash);
  497. switch (PTR_ERR(mp)) {
  498. case 0:
  499. break;
  500. case -EAGAIN:
  501. rehash:
  502. mdb = rcu_dereference_protected(br->mdb, 1);
  503. hash = br_ip_hash(mdb, group);
  504. break;
  505. default:
  506. goto out;
  507. }
  508. mp = kzalloc(sizeof(*mp), GFP_ATOMIC);
  509. if (unlikely(!mp))
  510. return ERR_PTR(-ENOMEM);
  511. mp->br = br;
  512. mp->addr = *group;
  513. setup_timer(&mp->timer, br_multicast_group_expired,
  514. (unsigned long)mp);
  515. hlist_add_head_rcu(&mp->hlist[mdb->ver], &mdb->mhash[hash]);
  516. mdb->size++;
  517. out:
  518. return mp;
  519. }
  520. struct net_bridge_port_group *br_multicast_new_port_group(
  521. struct net_bridge_port *port,
  522. struct br_ip *group,
  523. struct net_bridge_port_group __rcu *next,
  524. unsigned char state)
  525. {
  526. struct net_bridge_port_group *p;
  527. p = kzalloc(sizeof(*p), GFP_ATOMIC);
  528. if (unlikely(!p))
  529. return NULL;
  530. p->addr = *group;
  531. p->port = port;
  532. p->state = state;
  533. rcu_assign_pointer(p->next, next);
  534. hlist_add_head(&p->mglist, &port->mglist);
  535. setup_timer(&p->timer, br_multicast_port_group_expired,
  536. (unsigned long)p);
  537. return p;
  538. }
  539. static int br_multicast_add_group(struct net_bridge *br,
  540. struct net_bridge_port *port,
  541. struct br_ip *group)
  542. {
  543. struct net_bridge_mdb_entry *mp;
  544. struct net_bridge_port_group *p;
  545. struct net_bridge_port_group __rcu **pp;
  546. unsigned long now = jiffies;
  547. int err;
  548. spin_lock(&br->multicast_lock);
  549. if (!netif_running(br->dev) ||
  550. (port && port->state == BR_STATE_DISABLED))
  551. goto out;
  552. mp = br_multicast_new_group(br, port, group);
  553. err = PTR_ERR(mp);
  554. if (IS_ERR(mp))
  555. goto err;
  556. if (!port) {
  557. mp->mglist = true;
  558. mod_timer(&mp->timer, now + br->multicast_membership_interval);
  559. goto out;
  560. }
  561. for (pp = &mp->ports;
  562. (p = mlock_dereference(*pp, br)) != NULL;
  563. pp = &p->next) {
  564. if (p->port == port)
  565. goto found;
  566. if ((unsigned long)p->port < (unsigned long)port)
  567. break;
  568. }
  569. p = br_multicast_new_port_group(port, group, *pp, MDB_TEMPORARY);
  570. if (unlikely(!p))
  571. goto err;
  572. rcu_assign_pointer(*pp, p);
  573. br_mdb_notify(br->dev, port, group, RTM_NEWMDB);
  574. found:
  575. mod_timer(&p->timer, now + br->multicast_membership_interval);
  576. out:
  577. err = 0;
  578. err:
  579. spin_unlock(&br->multicast_lock);
  580. return err;
  581. }
  582. static int br_ip4_multicast_add_group(struct net_bridge *br,
  583. struct net_bridge_port *port,
  584. __be32 group,
  585. __u16 vid)
  586. {
  587. struct br_ip br_group;
  588. if (ipv4_is_local_multicast(group))
  589. return 0;
  590. br_group.u.ip4 = group;
  591. br_group.proto = htons(ETH_P_IP);
  592. br_group.vid = vid;
  593. return br_multicast_add_group(br, port, &br_group);
  594. }
  595. #if IS_ENABLED(CONFIG_IPV6)
  596. static int br_ip6_multicast_add_group(struct net_bridge *br,
  597. struct net_bridge_port *port,
  598. const struct in6_addr *group,
  599. __u16 vid)
  600. {
  601. struct br_ip br_group;
  602. if (ipv6_addr_is_ll_all_nodes(group))
  603. return 0;
  604. br_group.u.ip6 = *group;
  605. br_group.proto = htons(ETH_P_IPV6);
  606. br_group.vid = vid;
  607. return br_multicast_add_group(br, port, &br_group);
  608. }
  609. #endif
  610. static void br_multicast_router_expired(unsigned long data)
  611. {
  612. struct net_bridge_port *port = (void *)data;
  613. struct net_bridge *br = port->br;
  614. spin_lock(&br->multicast_lock);
  615. if (port->multicast_router != 1 ||
  616. timer_pending(&port->multicast_router_timer) ||
  617. hlist_unhashed(&port->rlist))
  618. goto out;
  619. hlist_del_init_rcu(&port->rlist);
  620. out:
  621. spin_unlock(&br->multicast_lock);
  622. }
  623. static void br_multicast_local_router_expired(unsigned long data)
  624. {
  625. }
  626. static void br_multicast_querier_expired(struct net_bridge *br,
  627. struct bridge_mcast_query *query)
  628. {
  629. spin_lock(&br->multicast_lock);
  630. if (!netif_running(br->dev) || br->multicast_disabled)
  631. goto out;
  632. br_multicast_start_querier(br, query);
  633. out:
  634. spin_unlock(&br->multicast_lock);
  635. }
  636. static void br_ip4_multicast_querier_expired(unsigned long data)
  637. {
  638. struct net_bridge *br = (void *)data;
  639. br_multicast_querier_expired(br, &br->ip4_query);
  640. }
  641. #if IS_ENABLED(CONFIG_IPV6)
  642. static void br_ip6_multicast_querier_expired(unsigned long data)
  643. {
  644. struct net_bridge *br = (void *)data;
  645. br_multicast_querier_expired(br, &br->ip6_query);
  646. }
  647. #endif
  648. static void __br_multicast_send_query(struct net_bridge *br,
  649. struct net_bridge_port *port,
  650. struct br_ip *ip)
  651. {
  652. struct sk_buff *skb;
  653. skb = br_multicast_alloc_query(br, ip);
  654. if (!skb)
  655. return;
  656. if (port) {
  657. __skb_push(skb, sizeof(struct ethhdr));
  658. skb->dev = port->dev;
  659. NF_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_OUT, skb, NULL, skb->dev,
  660. dev_queue_xmit);
  661. } else
  662. netif_rx(skb);
  663. }
  664. static void br_multicast_send_query(struct net_bridge *br,
  665. struct net_bridge_port *port,
  666. struct bridge_mcast_query *query)
  667. {
  668. unsigned long time;
  669. struct br_ip br_group;
  670. struct bridge_mcast_querier *querier = NULL;
  671. if (!netif_running(br->dev) || br->multicast_disabled ||
  672. !br->multicast_querier)
  673. return;
  674. memset(&br_group.u, 0, sizeof(br_group.u));
  675. if (port ? (query == &port->ip4_query) :
  676. (query == &br->ip4_query)) {
  677. querier = &br->ip4_querier;
  678. br_group.proto = htons(ETH_P_IP);
  679. #if IS_ENABLED(CONFIG_IPV6)
  680. } else {
  681. querier = &br->ip6_querier;
  682. br_group.proto = htons(ETH_P_IPV6);
  683. #endif
  684. }
  685. if (!querier || timer_pending(&querier->timer))
  686. return;
  687. __br_multicast_send_query(br, port, &br_group);
  688. time = jiffies;
  689. time += query->startup_sent < br->multicast_startup_query_count ?
  690. br->multicast_startup_query_interval :
  691. br->multicast_query_interval;
  692. mod_timer(&query->timer, time);
  693. }
  694. static void br_multicast_port_query_expired(struct net_bridge_port *port,
  695. struct bridge_mcast_query *query)
  696. {
  697. struct net_bridge *br = port->br;
  698. spin_lock(&br->multicast_lock);
  699. if (port->state == BR_STATE_DISABLED ||
  700. port->state == BR_STATE_BLOCKING)
  701. goto out;
  702. if (query->startup_sent < br->multicast_startup_query_count)
  703. query->startup_sent++;
  704. br_multicast_send_query(port->br, port, query);
  705. out:
  706. spin_unlock(&br->multicast_lock);
  707. }
  708. static void br_ip4_multicast_port_query_expired(unsigned long data)
  709. {
  710. struct net_bridge_port *port = (void *)data;
  711. br_multicast_port_query_expired(port, &port->ip4_query);
  712. }
  713. #if IS_ENABLED(CONFIG_IPV6)
  714. static void br_ip6_multicast_port_query_expired(unsigned long data)
  715. {
  716. struct net_bridge_port *port = (void *)data;
  717. br_multicast_port_query_expired(port, &port->ip6_query);
  718. }
  719. #endif
  720. void br_multicast_add_port(struct net_bridge_port *port)
  721. {
  722. port->multicast_router = 1;
  723. setup_timer(&port->multicast_router_timer, br_multicast_router_expired,
  724. (unsigned long)port);
  725. setup_timer(&port->ip4_query.timer, br_ip4_multicast_port_query_expired,
  726. (unsigned long)port);
  727. #if IS_ENABLED(CONFIG_IPV6)
  728. setup_timer(&port->ip6_query.timer, br_ip6_multicast_port_query_expired,
  729. (unsigned long)port);
  730. #endif
  731. }
  732. void br_multicast_del_port(struct net_bridge_port *port)
  733. {
  734. del_timer_sync(&port->multicast_router_timer);
  735. }
  736. static void br_multicast_enable(struct bridge_mcast_query *query)
  737. {
  738. query->startup_sent = 0;
  739. if (try_to_del_timer_sync(&query->timer) >= 0 ||
  740. del_timer(&query->timer))
  741. mod_timer(&query->timer, jiffies);
  742. }
  743. void br_multicast_enable_port(struct net_bridge_port *port)
  744. {
  745. struct net_bridge *br = port->br;
  746. spin_lock(&br->multicast_lock);
  747. if (br->multicast_disabled || !netif_running(br->dev))
  748. goto out;
  749. br_multicast_enable(&port->ip4_query);
  750. #if IS_ENABLED(CONFIG_IPV6)
  751. br_multicast_enable(&port->ip6_query);
  752. #endif
  753. out:
  754. spin_unlock(&br->multicast_lock);
  755. }
  756. void br_multicast_disable_port(struct net_bridge_port *port)
  757. {
  758. struct net_bridge *br = port->br;
  759. struct net_bridge_port_group *pg;
  760. struct hlist_node *n;
  761. spin_lock(&br->multicast_lock);
  762. hlist_for_each_entry_safe(pg, n, &port->mglist, mglist)
  763. br_multicast_del_pg(br, pg);
  764. if (!hlist_unhashed(&port->rlist))
  765. hlist_del_init_rcu(&port->rlist);
  766. del_timer(&port->multicast_router_timer);
  767. del_timer(&port->ip4_query.timer);
  768. #if IS_ENABLED(CONFIG_IPV6)
  769. del_timer(&port->ip6_query.timer);
  770. #endif
  771. spin_unlock(&br->multicast_lock);
  772. }
  773. static int br_ip4_multicast_igmp3_report(struct net_bridge *br,
  774. struct net_bridge_port *port,
  775. struct sk_buff *skb,
  776. u16 vid)
  777. {
  778. struct igmpv3_report *ih;
  779. struct igmpv3_grec *grec;
  780. int i;
  781. int len;
  782. int num;
  783. int type;
  784. int err = 0;
  785. __be32 group;
  786. if (!pskb_may_pull(skb, sizeof(*ih)))
  787. return -EINVAL;
  788. ih = igmpv3_report_hdr(skb);
  789. num = ntohs(ih->ngrec);
  790. len = sizeof(*ih);
  791. for (i = 0; i < num; i++) {
  792. len += sizeof(*grec);
  793. if (!pskb_may_pull(skb, len))
  794. return -EINVAL;
  795. grec = (void *)(skb->data + len - sizeof(*grec));
  796. group = grec->grec_mca;
  797. type = grec->grec_type;
  798. len += ntohs(grec->grec_nsrcs) * 4;
  799. if (!pskb_may_pull(skb, len))
  800. return -EINVAL;
  801. /* We treat this as an IGMPv2 report for now. */
  802. switch (type) {
  803. case IGMPV3_MODE_IS_INCLUDE:
  804. case IGMPV3_MODE_IS_EXCLUDE:
  805. case IGMPV3_CHANGE_TO_INCLUDE:
  806. case IGMPV3_CHANGE_TO_EXCLUDE:
  807. case IGMPV3_ALLOW_NEW_SOURCES:
  808. case IGMPV3_BLOCK_OLD_SOURCES:
  809. break;
  810. default:
  811. continue;
  812. }
  813. err = br_ip4_multicast_add_group(br, port, group, vid);
  814. if (err)
  815. break;
  816. }
  817. return err;
  818. }
  819. #if IS_ENABLED(CONFIG_IPV6)
  820. static int br_ip6_multicast_mld2_report(struct net_bridge *br,
  821. struct net_bridge_port *port,
  822. struct sk_buff *skb,
  823. u16 vid)
  824. {
  825. struct icmp6hdr *icmp6h;
  826. struct mld2_grec *grec;
  827. int i;
  828. int len;
  829. int num;
  830. int err = 0;
  831. if (!pskb_may_pull(skb, sizeof(*icmp6h)))
  832. return -EINVAL;
  833. icmp6h = icmp6_hdr(skb);
  834. num = ntohs(icmp6h->icmp6_dataun.un_data16[1]);
  835. len = sizeof(*icmp6h);
  836. for (i = 0; i < num; i++) {
  837. __be16 *nsrcs, _nsrcs;
  838. nsrcs = skb_header_pointer(skb,
  839. len + offsetof(struct mld2_grec,
  840. grec_nsrcs),
  841. sizeof(_nsrcs), &_nsrcs);
  842. if (!nsrcs)
  843. return -EINVAL;
  844. if (!pskb_may_pull(skb,
  845. len + sizeof(*grec) +
  846. sizeof(struct in6_addr) * ntohs(*nsrcs)))
  847. return -EINVAL;
  848. grec = (struct mld2_grec *)(skb->data + len);
  849. len += sizeof(*grec) +
  850. sizeof(struct in6_addr) * ntohs(*nsrcs);
  851. /* We treat these as MLDv1 reports for now. */
  852. switch (grec->grec_type) {
  853. case MLD2_MODE_IS_INCLUDE:
  854. case MLD2_MODE_IS_EXCLUDE:
  855. case MLD2_CHANGE_TO_INCLUDE:
  856. case MLD2_CHANGE_TO_EXCLUDE:
  857. case MLD2_ALLOW_NEW_SOURCES:
  858. case MLD2_BLOCK_OLD_SOURCES:
  859. break;
  860. default:
  861. continue;
  862. }
  863. err = br_ip6_multicast_add_group(br, port, &grec->grec_mca,
  864. vid);
  865. if (!err)
  866. break;
  867. }
  868. return err;
  869. }
  870. #endif
  871. static void
  872. br_multicast_update_querier_timer(struct net_bridge *br,
  873. struct bridge_mcast_querier *querier,
  874. unsigned long max_delay)
  875. {
  876. if (!timer_pending(&querier->timer))
  877. querier->delay_time = jiffies + max_delay;
  878. mod_timer(&querier->timer, jiffies + br->multicast_querier_interval);
  879. }
  880. /*
  881. * Add port to router_list
  882. * list is maintained ordered by pointer value
  883. * and locked by br->multicast_lock and RCU
  884. */
  885. static void br_multicast_add_router(struct net_bridge *br,
  886. struct net_bridge_port *port)
  887. {
  888. struct net_bridge_port *p;
  889. struct hlist_node *slot = NULL;
  890. hlist_for_each_entry(p, &br->router_list, rlist) {
  891. if ((unsigned long) port >= (unsigned long) p)
  892. break;
  893. slot = &p->rlist;
  894. }
  895. if (slot)
  896. hlist_add_after_rcu(slot, &port->rlist);
  897. else
  898. hlist_add_head_rcu(&port->rlist, &br->router_list);
  899. }
  900. static void br_multicast_mark_router(struct net_bridge *br,
  901. struct net_bridge_port *port)
  902. {
  903. unsigned long now = jiffies;
  904. if (!port) {
  905. if (br->multicast_router == 1)
  906. mod_timer(&br->multicast_router_timer,
  907. now + br->multicast_querier_interval);
  908. return;
  909. }
  910. if (port->multicast_router != 1)
  911. return;
  912. if (!hlist_unhashed(&port->rlist))
  913. goto timer;
  914. br_multicast_add_router(br, port);
  915. timer:
  916. mod_timer(&port->multicast_router_timer,
  917. now + br->multicast_querier_interval);
  918. }
  919. static void br_multicast_query_received(struct net_bridge *br,
  920. struct net_bridge_port *port,
  921. struct bridge_mcast_querier *querier,
  922. int saddr,
  923. unsigned long max_delay)
  924. {
  925. if (saddr)
  926. br_multicast_update_querier_timer(br, querier, max_delay);
  927. else if (timer_pending(&querier->timer))
  928. return;
  929. br_multicast_mark_router(br, port);
  930. }
  931. static int br_ip4_multicast_query(struct net_bridge *br,
  932. struct net_bridge_port *port,
  933. struct sk_buff *skb,
  934. u16 vid)
  935. {
  936. const struct iphdr *iph = ip_hdr(skb);
  937. struct igmphdr *ih = igmp_hdr(skb);
  938. struct net_bridge_mdb_entry *mp;
  939. struct igmpv3_query *ih3;
  940. struct net_bridge_port_group *p;
  941. struct net_bridge_port_group __rcu **pp;
  942. unsigned long max_delay;
  943. unsigned long now = jiffies;
  944. __be32 group;
  945. int err = 0;
  946. spin_lock(&br->multicast_lock);
  947. if (!netif_running(br->dev) ||
  948. (port && port->state == BR_STATE_DISABLED))
  949. goto out;
  950. group = ih->group;
  951. if (skb->len == sizeof(*ih)) {
  952. max_delay = ih->code * (HZ / IGMP_TIMER_SCALE);
  953. if (!max_delay) {
  954. max_delay = 10 * HZ;
  955. group = 0;
  956. }
  957. } else {
  958. if (!pskb_may_pull(skb, sizeof(struct igmpv3_query))) {
  959. err = -EINVAL;
  960. goto out;
  961. }
  962. ih3 = igmpv3_query_hdr(skb);
  963. if (ih3->nsrcs)
  964. goto out;
  965. max_delay = ih3->code ?
  966. IGMPV3_MRC(ih3->code) * (HZ / IGMP_TIMER_SCALE) : 1;
  967. }
  968. br_multicast_query_received(br, port, &br->ip4_querier, !!iph->saddr,
  969. max_delay);
  970. if (!group)
  971. goto out;
  972. mp = br_mdb_ip4_get(mlock_dereference(br->mdb, br), group, vid);
  973. if (!mp)
  974. goto out;
  975. max_delay *= br->multicast_last_member_count;
  976. if (mp->mglist &&
  977. (timer_pending(&mp->timer) ?
  978. time_after(mp->timer.expires, now + max_delay) :
  979. try_to_del_timer_sync(&mp->timer) >= 0))
  980. mod_timer(&mp->timer, now + max_delay);
  981. for (pp = &mp->ports;
  982. (p = mlock_dereference(*pp, br)) != NULL;
  983. pp = &p->next) {
  984. if (timer_pending(&p->timer) ?
  985. time_after(p->timer.expires, now + max_delay) :
  986. try_to_del_timer_sync(&p->timer) >= 0)
  987. mod_timer(&p->timer, now + max_delay);
  988. }
  989. out:
  990. spin_unlock(&br->multicast_lock);
  991. return err;
  992. }
  993. #if IS_ENABLED(CONFIG_IPV6)
  994. static int br_ip6_multicast_query(struct net_bridge *br,
  995. struct net_bridge_port *port,
  996. struct sk_buff *skb,
  997. u16 vid)
  998. {
  999. const struct ipv6hdr *ip6h = ipv6_hdr(skb);
  1000. struct mld_msg *mld;
  1001. struct net_bridge_mdb_entry *mp;
  1002. struct mld2_query *mld2q;
  1003. struct net_bridge_port_group *p;
  1004. struct net_bridge_port_group __rcu **pp;
  1005. unsigned long max_delay;
  1006. unsigned long now = jiffies;
  1007. const struct in6_addr *group = NULL;
  1008. int err = 0;
  1009. spin_lock(&br->multicast_lock);
  1010. if (!netif_running(br->dev) ||
  1011. (port && port->state == BR_STATE_DISABLED))
  1012. goto out;
  1013. if (skb->len == sizeof(*mld)) {
  1014. if (!pskb_may_pull(skb, sizeof(*mld))) {
  1015. err = -EINVAL;
  1016. goto out;
  1017. }
  1018. mld = (struct mld_msg *) icmp6_hdr(skb);
  1019. max_delay = msecs_to_jiffies(ntohs(mld->mld_maxdelay));
  1020. if (max_delay)
  1021. group = &mld->mld_mca;
  1022. } else {
  1023. if (!pskb_may_pull(skb, sizeof(*mld2q))) {
  1024. err = -EINVAL;
  1025. goto out;
  1026. }
  1027. mld2q = (struct mld2_query *)icmp6_hdr(skb);
  1028. if (!mld2q->mld2q_nsrcs)
  1029. group = &mld2q->mld2q_mca;
  1030. max_delay = max(msecs_to_jiffies(mldv2_mrc(mld2q)), 1UL);
  1031. }
  1032. br_multicast_query_received(br, port, &br->ip6_querier,
  1033. !ipv6_addr_any(&ip6h->saddr), max_delay);
  1034. if (!group)
  1035. goto out;
  1036. mp = br_mdb_ip6_get(mlock_dereference(br->mdb, br), group, vid);
  1037. if (!mp)
  1038. goto out;
  1039. max_delay *= br->multicast_last_member_count;
  1040. if (mp->mglist &&
  1041. (timer_pending(&mp->timer) ?
  1042. time_after(mp->timer.expires, now + max_delay) :
  1043. try_to_del_timer_sync(&mp->timer) >= 0))
  1044. mod_timer(&mp->timer, now + max_delay);
  1045. for (pp = &mp->ports;
  1046. (p = mlock_dereference(*pp, br)) != NULL;
  1047. pp = &p->next) {
  1048. if (timer_pending(&p->timer) ?
  1049. time_after(p->timer.expires, now + max_delay) :
  1050. try_to_del_timer_sync(&p->timer) >= 0)
  1051. mod_timer(&p->timer, now + max_delay);
  1052. }
  1053. out:
  1054. spin_unlock(&br->multicast_lock);
  1055. return err;
  1056. }
  1057. #endif
  1058. static void br_multicast_leave_group(struct net_bridge *br,
  1059. struct net_bridge_port *port,
  1060. struct br_ip *group,
  1061. struct bridge_mcast_querier *querier,
  1062. struct bridge_mcast_query *query)
  1063. {
  1064. struct net_bridge_mdb_htable *mdb;
  1065. struct net_bridge_mdb_entry *mp;
  1066. struct net_bridge_port_group *p;
  1067. unsigned long now;
  1068. unsigned long time;
  1069. spin_lock(&br->multicast_lock);
  1070. if (!netif_running(br->dev) ||
  1071. (port && port->state == BR_STATE_DISABLED) ||
  1072. timer_pending(&querier->timer))
  1073. goto out;
  1074. mdb = mlock_dereference(br->mdb, br);
  1075. mp = br_mdb_ip_get(mdb, group);
  1076. if (!mp)
  1077. goto out;
  1078. if (br->multicast_querier) {
  1079. __br_multicast_send_query(br, port, &mp->addr);
  1080. time = jiffies + br->multicast_last_member_count *
  1081. br->multicast_last_member_interval;
  1082. mod_timer(&query->timer, time);
  1083. for (p = mlock_dereference(mp->ports, br);
  1084. p != NULL;
  1085. p = mlock_dereference(p->next, br)) {
  1086. if (p->port != port)
  1087. continue;
  1088. if (!hlist_unhashed(&p->mglist) &&
  1089. (timer_pending(&p->timer) ?
  1090. time_after(p->timer.expires, time) :
  1091. try_to_del_timer_sync(&p->timer) >= 0)) {
  1092. mod_timer(&p->timer, time);
  1093. }
  1094. break;
  1095. }
  1096. }
  1097. if (port && (port->flags & BR_MULTICAST_FAST_LEAVE)) {
  1098. struct net_bridge_port_group __rcu **pp;
  1099. for (pp = &mp->ports;
  1100. (p = mlock_dereference(*pp, br)) != NULL;
  1101. pp = &p->next) {
  1102. if (p->port != port)
  1103. continue;
  1104. rcu_assign_pointer(*pp, p->next);
  1105. hlist_del_init(&p->mglist);
  1106. del_timer(&p->timer);
  1107. call_rcu_bh(&p->rcu, br_multicast_free_pg);
  1108. br_mdb_notify(br->dev, port, group, RTM_DELMDB);
  1109. if (!mp->ports && !mp->mglist &&
  1110. netif_running(br->dev))
  1111. mod_timer(&mp->timer, jiffies);
  1112. }
  1113. goto out;
  1114. }
  1115. now = jiffies;
  1116. time = now + br->multicast_last_member_count *
  1117. br->multicast_last_member_interval;
  1118. if (!port) {
  1119. if (mp->mglist &&
  1120. (timer_pending(&mp->timer) ?
  1121. time_after(mp->timer.expires, time) :
  1122. try_to_del_timer_sync(&mp->timer) >= 0)) {
  1123. mod_timer(&mp->timer, time);
  1124. }
  1125. goto out;
  1126. }
  1127. for (p = mlock_dereference(mp->ports, br);
  1128. p != NULL;
  1129. p = mlock_dereference(p->next, br)) {
  1130. if (p->port != port)
  1131. continue;
  1132. if (!hlist_unhashed(&p->mglist) &&
  1133. (timer_pending(&p->timer) ?
  1134. time_after(p->timer.expires, time) :
  1135. try_to_del_timer_sync(&p->timer) >= 0)) {
  1136. mod_timer(&p->timer, time);
  1137. }
  1138. break;
  1139. }
  1140. out:
  1141. spin_unlock(&br->multicast_lock);
  1142. }
  1143. static void br_ip4_multicast_leave_group(struct net_bridge *br,
  1144. struct net_bridge_port *port,
  1145. __be32 group,
  1146. __u16 vid)
  1147. {
  1148. struct br_ip br_group;
  1149. struct bridge_mcast_query *query = port ? &port->ip4_query :
  1150. &br->ip4_query;
  1151. if (ipv4_is_local_multicast(group))
  1152. return;
  1153. br_group.u.ip4 = group;
  1154. br_group.proto = htons(ETH_P_IP);
  1155. br_group.vid = vid;
  1156. br_multicast_leave_group(br, port, &br_group, &br->ip4_querier, query);
  1157. }
  1158. #if IS_ENABLED(CONFIG_IPV6)
  1159. static void br_ip6_multicast_leave_group(struct net_bridge *br,
  1160. struct net_bridge_port *port,
  1161. const struct in6_addr *group,
  1162. __u16 vid)
  1163. {
  1164. struct br_ip br_group;
  1165. struct bridge_mcast_query *query = port ? &port->ip6_query :
  1166. &br->ip6_query;
  1167. if (ipv6_addr_is_ll_all_nodes(group))
  1168. return;
  1169. br_group.u.ip6 = *group;
  1170. br_group.proto = htons(ETH_P_IPV6);
  1171. br_group.vid = vid;
  1172. br_multicast_leave_group(br, port, &br_group, &br->ip6_querier, query);
  1173. }
  1174. #endif
  1175. static int br_multicast_ipv4_rcv(struct net_bridge *br,
  1176. struct net_bridge_port *port,
  1177. struct sk_buff *skb,
  1178. u16 vid)
  1179. {
  1180. struct sk_buff *skb2 = skb;
  1181. const struct iphdr *iph;
  1182. struct igmphdr *ih;
  1183. unsigned int len;
  1184. unsigned int offset;
  1185. int err;
  1186. /* We treat OOM as packet loss for now. */
  1187. if (!pskb_may_pull(skb, sizeof(*iph)))
  1188. return -EINVAL;
  1189. iph = ip_hdr(skb);
  1190. if (iph->ihl < 5 || iph->version != 4)
  1191. return -EINVAL;
  1192. if (!pskb_may_pull(skb, ip_hdrlen(skb)))
  1193. return -EINVAL;
  1194. iph = ip_hdr(skb);
  1195. if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl)))
  1196. return -EINVAL;
  1197. if (iph->protocol != IPPROTO_IGMP) {
  1198. if (!ipv4_is_local_multicast(iph->daddr))
  1199. BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
  1200. return 0;
  1201. }
  1202. len = ntohs(iph->tot_len);
  1203. if (skb->len < len || len < ip_hdrlen(skb))
  1204. return -EINVAL;
  1205. if (skb->len > len) {
  1206. skb2 = skb_clone(skb, GFP_ATOMIC);
  1207. if (!skb2)
  1208. return -ENOMEM;
  1209. err = pskb_trim_rcsum(skb2, len);
  1210. if (err)
  1211. goto err_out;
  1212. }
  1213. len -= ip_hdrlen(skb2);
  1214. offset = skb_network_offset(skb2) + ip_hdrlen(skb2);
  1215. __skb_pull(skb2, offset);
  1216. skb_reset_transport_header(skb2);
  1217. err = -EINVAL;
  1218. if (!pskb_may_pull(skb2, sizeof(*ih)))
  1219. goto out;
  1220. switch (skb2->ip_summed) {
  1221. case CHECKSUM_COMPLETE:
  1222. if (!csum_fold(skb2->csum))
  1223. break;
  1224. /* fall through */
  1225. case CHECKSUM_NONE:
  1226. skb2->csum = 0;
  1227. if (skb_checksum_complete(skb2))
  1228. goto out;
  1229. }
  1230. err = 0;
  1231. BR_INPUT_SKB_CB(skb)->igmp = 1;
  1232. ih = igmp_hdr(skb2);
  1233. switch (ih->type) {
  1234. case IGMP_HOST_MEMBERSHIP_REPORT:
  1235. case IGMPV2_HOST_MEMBERSHIP_REPORT:
  1236. BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
  1237. err = br_ip4_multicast_add_group(br, port, ih->group, vid);
  1238. break;
  1239. case IGMPV3_HOST_MEMBERSHIP_REPORT:
  1240. err = br_ip4_multicast_igmp3_report(br, port, skb2, vid);
  1241. break;
  1242. case IGMP_HOST_MEMBERSHIP_QUERY:
  1243. err = br_ip4_multicast_query(br, port, skb2, vid);
  1244. break;
  1245. case IGMP_HOST_LEAVE_MESSAGE:
  1246. br_ip4_multicast_leave_group(br, port, ih->group, vid);
  1247. break;
  1248. }
  1249. out:
  1250. __skb_push(skb2, offset);
  1251. err_out:
  1252. if (skb2 != skb)
  1253. kfree_skb(skb2);
  1254. return err;
  1255. }
  1256. #if IS_ENABLED(CONFIG_IPV6)
  1257. static int br_multicast_ipv6_rcv(struct net_bridge *br,
  1258. struct net_bridge_port *port,
  1259. struct sk_buff *skb,
  1260. u16 vid)
  1261. {
  1262. struct sk_buff *skb2;
  1263. const struct ipv6hdr *ip6h;
  1264. u8 icmp6_type;
  1265. u8 nexthdr;
  1266. __be16 frag_off;
  1267. unsigned int len;
  1268. int offset;
  1269. int err;
  1270. if (!pskb_may_pull(skb, sizeof(*ip6h)))
  1271. return -EINVAL;
  1272. ip6h = ipv6_hdr(skb);
  1273. /*
  1274. * We're interested in MLD messages only.
  1275. * - Version is 6
  1276. * - MLD has always Router Alert hop-by-hop option
  1277. * - But we do not support jumbrograms.
  1278. */
  1279. if (ip6h->version != 6)
  1280. return 0;
  1281. /* Prevent flooding this packet if there is no listener present */
  1282. if (!ipv6_addr_is_ll_all_nodes(&ip6h->daddr))
  1283. BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
  1284. if (ip6h->nexthdr != IPPROTO_HOPOPTS ||
  1285. ip6h->payload_len == 0)
  1286. return 0;
  1287. len = ntohs(ip6h->payload_len) + sizeof(*ip6h);
  1288. if (skb->len < len)
  1289. return -EINVAL;
  1290. nexthdr = ip6h->nexthdr;
  1291. offset = ipv6_skip_exthdr(skb, sizeof(*ip6h), &nexthdr, &frag_off);
  1292. if (offset < 0 || nexthdr != IPPROTO_ICMPV6)
  1293. return 0;
  1294. /* Okay, we found ICMPv6 header */
  1295. skb2 = skb_clone(skb, GFP_ATOMIC);
  1296. if (!skb2)
  1297. return -ENOMEM;
  1298. err = -EINVAL;
  1299. if (!pskb_may_pull(skb2, offset + sizeof(struct icmp6hdr)))
  1300. goto out;
  1301. len -= offset - skb_network_offset(skb2);
  1302. __skb_pull(skb2, offset);
  1303. skb_reset_transport_header(skb2);
  1304. skb_postpull_rcsum(skb2, skb_network_header(skb2),
  1305. skb_network_header_len(skb2));
  1306. icmp6_type = icmp6_hdr(skb2)->icmp6_type;
  1307. switch (icmp6_type) {
  1308. case ICMPV6_MGM_QUERY:
  1309. case ICMPV6_MGM_REPORT:
  1310. case ICMPV6_MGM_REDUCTION:
  1311. case ICMPV6_MLD2_REPORT:
  1312. break;
  1313. default:
  1314. err = 0;
  1315. goto out;
  1316. }
  1317. /* Okay, we found MLD message. Check further. */
  1318. if (skb2->len > len) {
  1319. err = pskb_trim_rcsum(skb2, len);
  1320. if (err)
  1321. goto out;
  1322. err = -EINVAL;
  1323. }
  1324. ip6h = ipv6_hdr(skb2);
  1325. switch (skb2->ip_summed) {
  1326. case CHECKSUM_COMPLETE:
  1327. if (!csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr, skb2->len,
  1328. IPPROTO_ICMPV6, skb2->csum))
  1329. break;
  1330. /*FALLTHROUGH*/
  1331. case CHECKSUM_NONE:
  1332. skb2->csum = ~csum_unfold(csum_ipv6_magic(&ip6h->saddr,
  1333. &ip6h->daddr,
  1334. skb2->len,
  1335. IPPROTO_ICMPV6, 0));
  1336. if (__skb_checksum_complete(skb2))
  1337. goto out;
  1338. }
  1339. err = 0;
  1340. BR_INPUT_SKB_CB(skb)->igmp = 1;
  1341. switch (icmp6_type) {
  1342. case ICMPV6_MGM_REPORT:
  1343. {
  1344. struct mld_msg *mld;
  1345. if (!pskb_may_pull(skb2, sizeof(*mld))) {
  1346. err = -EINVAL;
  1347. goto out;
  1348. }
  1349. mld = (struct mld_msg *)skb_transport_header(skb2);
  1350. BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
  1351. err = br_ip6_multicast_add_group(br, port, &mld->mld_mca, vid);
  1352. break;
  1353. }
  1354. case ICMPV6_MLD2_REPORT:
  1355. err = br_ip6_multicast_mld2_report(br, port, skb2, vid);
  1356. break;
  1357. case ICMPV6_MGM_QUERY:
  1358. err = br_ip6_multicast_query(br, port, skb2, vid);
  1359. break;
  1360. case ICMPV6_MGM_REDUCTION:
  1361. {
  1362. struct mld_msg *mld;
  1363. if (!pskb_may_pull(skb2, sizeof(*mld))) {
  1364. err = -EINVAL;
  1365. goto out;
  1366. }
  1367. mld = (struct mld_msg *)skb_transport_header(skb2);
  1368. br_ip6_multicast_leave_group(br, port, &mld->mld_mca, vid);
  1369. }
  1370. }
  1371. out:
  1372. kfree_skb(skb2);
  1373. return err;
  1374. }
  1375. #endif
  1376. int br_multicast_rcv(struct net_bridge *br, struct net_bridge_port *port,
  1377. struct sk_buff *skb, u16 vid)
  1378. {
  1379. BR_INPUT_SKB_CB(skb)->igmp = 0;
  1380. BR_INPUT_SKB_CB(skb)->mrouters_only = 0;
  1381. if (br->multicast_disabled)
  1382. return 0;
  1383. switch (skb->protocol) {
  1384. case htons(ETH_P_IP):
  1385. return br_multicast_ipv4_rcv(br, port, skb, vid);
  1386. #if IS_ENABLED(CONFIG_IPV6)
  1387. case htons(ETH_P_IPV6):
  1388. return br_multicast_ipv6_rcv(br, port, skb, vid);
  1389. #endif
  1390. }
  1391. return 0;
  1392. }
  1393. static void br_multicast_query_expired(struct net_bridge *br,
  1394. struct bridge_mcast_query *query)
  1395. {
  1396. spin_lock(&br->multicast_lock);
  1397. if (query->startup_sent < br->multicast_startup_query_count)
  1398. query->startup_sent++;
  1399. br_multicast_send_query(br, NULL, query);
  1400. spin_unlock(&br->multicast_lock);
  1401. }
  1402. static void br_ip4_multicast_query_expired(unsigned long data)
  1403. {
  1404. struct net_bridge *br = (void *)data;
  1405. br_multicast_query_expired(br, &br->ip4_query);
  1406. }
  1407. #if IS_ENABLED(CONFIG_IPV6)
  1408. static void br_ip6_multicast_query_expired(unsigned long data)
  1409. {
  1410. struct net_bridge *br = (void *)data;
  1411. br_multicast_query_expired(br, &br->ip6_query);
  1412. }
  1413. #endif
  1414. void br_multicast_init(struct net_bridge *br)
  1415. {
  1416. br->hash_elasticity = 4;
  1417. br->hash_max = 512;
  1418. br->multicast_router = 1;
  1419. br->multicast_querier = 0;
  1420. br->multicast_query_use_ifaddr = 0;
  1421. br->multicast_last_member_count = 2;
  1422. br->multicast_startup_query_count = 2;
  1423. br->multicast_last_member_interval = HZ;
  1424. br->multicast_query_response_interval = 10 * HZ;
  1425. br->multicast_startup_query_interval = 125 * HZ / 4;
  1426. br->multicast_query_interval = 125 * HZ;
  1427. br->multicast_querier_interval = 255 * HZ;
  1428. br->multicast_membership_interval = 260 * HZ;
  1429. br->ip4_querier.delay_time = 0;
  1430. #if IS_ENABLED(CONFIG_IPV6)
  1431. br->ip6_querier.delay_time = 0;
  1432. #endif
  1433. spin_lock_init(&br->multicast_lock);
  1434. setup_timer(&br->multicast_router_timer,
  1435. br_multicast_local_router_expired, 0);
  1436. setup_timer(&br->ip4_querier.timer, br_ip4_multicast_querier_expired,
  1437. (unsigned long)br);
  1438. setup_timer(&br->ip4_query.timer, br_ip4_multicast_query_expired,
  1439. (unsigned long)br);
  1440. #if IS_ENABLED(CONFIG_IPV6)
  1441. setup_timer(&br->ip6_querier.timer, br_ip6_multicast_querier_expired,
  1442. (unsigned long)br);
  1443. setup_timer(&br->ip6_query.timer, br_ip6_multicast_query_expired,
  1444. (unsigned long)br);
  1445. #endif
  1446. }
  1447. static void __br_multicast_open(struct net_bridge *br,
  1448. struct bridge_mcast_query *query)
  1449. {
  1450. query->startup_sent = 0;
  1451. if (br->multicast_disabled)
  1452. return;
  1453. mod_timer(&query->timer, jiffies);
  1454. }
  1455. void br_multicast_open(struct net_bridge *br)
  1456. {
  1457. __br_multicast_open(br, &br->ip4_query);
  1458. #if IS_ENABLED(CONFIG_IPV6)
  1459. __br_multicast_open(br, &br->ip6_query);
  1460. #endif
  1461. }
  1462. void br_multicast_stop(struct net_bridge *br)
  1463. {
  1464. struct net_bridge_mdb_htable *mdb;
  1465. struct net_bridge_mdb_entry *mp;
  1466. struct hlist_node *n;
  1467. u32 ver;
  1468. int i;
  1469. del_timer_sync(&br->multicast_router_timer);
  1470. del_timer_sync(&br->ip4_querier.timer);
  1471. del_timer_sync(&br->ip4_query.timer);
  1472. #if IS_ENABLED(CONFIG_IPV6)
  1473. del_timer_sync(&br->ip6_querier.timer);
  1474. del_timer_sync(&br->ip6_query.timer);
  1475. #endif
  1476. spin_lock_bh(&br->multicast_lock);
  1477. mdb = mlock_dereference(br->mdb, br);
  1478. if (!mdb)
  1479. goto out;
  1480. br->mdb = NULL;
  1481. ver = mdb->ver;
  1482. for (i = 0; i < mdb->max; i++) {
  1483. hlist_for_each_entry_safe(mp, n, &mdb->mhash[i],
  1484. hlist[ver]) {
  1485. del_timer(&mp->timer);
  1486. call_rcu_bh(&mp->rcu, br_multicast_free_group);
  1487. }
  1488. }
  1489. if (mdb->old) {
  1490. spin_unlock_bh(&br->multicast_lock);
  1491. rcu_barrier_bh();
  1492. spin_lock_bh(&br->multicast_lock);
  1493. WARN_ON(mdb->old);
  1494. }
  1495. mdb->old = mdb;
  1496. call_rcu_bh(&mdb->rcu, br_mdb_free);
  1497. out:
  1498. spin_unlock_bh(&br->multicast_lock);
  1499. }
  1500. int br_multicast_set_router(struct net_bridge *br, unsigned long val)
  1501. {
  1502. int err = -ENOENT;
  1503. spin_lock_bh(&br->multicast_lock);
  1504. if (!netif_running(br->dev))
  1505. goto unlock;
  1506. switch (val) {
  1507. case 0:
  1508. case 2:
  1509. del_timer(&br->multicast_router_timer);
  1510. /* fall through */
  1511. case 1:
  1512. br->multicast_router = val;
  1513. err = 0;
  1514. break;
  1515. default:
  1516. err = -EINVAL;
  1517. break;
  1518. }
  1519. unlock:
  1520. spin_unlock_bh(&br->multicast_lock);
  1521. return err;
  1522. }
  1523. int br_multicast_set_port_router(struct net_bridge_port *p, unsigned long val)
  1524. {
  1525. struct net_bridge *br = p->br;
  1526. int err = -ENOENT;
  1527. spin_lock(&br->multicast_lock);
  1528. if (!netif_running(br->dev) || p->state == BR_STATE_DISABLED)
  1529. goto unlock;
  1530. switch (val) {
  1531. case 0:
  1532. case 1:
  1533. case 2:
  1534. p->multicast_router = val;
  1535. err = 0;
  1536. if (val < 2 && !hlist_unhashed(&p->rlist))
  1537. hlist_del_init_rcu(&p->rlist);
  1538. if (val == 1)
  1539. break;
  1540. del_timer(&p->multicast_router_timer);
  1541. if (val == 0)
  1542. break;
  1543. br_multicast_add_router(br, p);
  1544. break;
  1545. default:
  1546. err = -EINVAL;
  1547. break;
  1548. }
  1549. unlock:
  1550. spin_unlock(&br->multicast_lock);
  1551. return err;
  1552. }
  1553. static void br_multicast_start_querier(struct net_bridge *br,
  1554. struct bridge_mcast_query *query)
  1555. {
  1556. struct net_bridge_port *port;
  1557. __br_multicast_open(br, query);
  1558. list_for_each_entry(port, &br->port_list, list) {
  1559. if (port->state == BR_STATE_DISABLED ||
  1560. port->state == BR_STATE_BLOCKING)
  1561. continue;
  1562. if (query == &br->ip4_query)
  1563. br_multicast_enable(&port->ip4_query);
  1564. #if IS_ENABLED(CONFIG_IPV6)
  1565. else
  1566. br_multicast_enable(&port->ip6_query);
  1567. #endif
  1568. }
  1569. }
  1570. int br_multicast_toggle(struct net_bridge *br, unsigned long val)
  1571. {
  1572. int err = 0;
  1573. struct net_bridge_mdb_htable *mdb;
  1574. spin_lock_bh(&br->multicast_lock);
  1575. if (br->multicast_disabled == !val)
  1576. goto unlock;
  1577. br->multicast_disabled = !val;
  1578. if (br->multicast_disabled)
  1579. goto unlock;
  1580. if (!netif_running(br->dev))
  1581. goto unlock;
  1582. mdb = mlock_dereference(br->mdb, br);
  1583. if (mdb) {
  1584. if (mdb->old) {
  1585. err = -EEXIST;
  1586. rollback:
  1587. br->multicast_disabled = !!val;
  1588. goto unlock;
  1589. }
  1590. err = br_mdb_rehash(&br->mdb, mdb->max,
  1591. br->hash_elasticity);
  1592. if (err)
  1593. goto rollback;
  1594. }
  1595. br_multicast_start_querier(br, &br->ip4_query);
  1596. #if IS_ENABLED(CONFIG_IPV6)
  1597. br_multicast_start_querier(br, &br->ip6_query);
  1598. #endif
  1599. unlock:
  1600. spin_unlock_bh(&br->multicast_lock);
  1601. return err;
  1602. }
  1603. int br_multicast_set_querier(struct net_bridge *br, unsigned long val)
  1604. {
  1605. unsigned long max_delay;
  1606. val = !!val;
  1607. spin_lock_bh(&br->multicast_lock);
  1608. if (br->multicast_querier == val)
  1609. goto unlock;
  1610. br->multicast_querier = val;
  1611. if (!val)
  1612. goto unlock;
  1613. max_delay = br->multicast_query_response_interval;
  1614. if (!timer_pending(&br->ip4_querier.timer))
  1615. br->ip4_querier.delay_time = jiffies + max_delay;
  1616. br_multicast_start_querier(br, &br->ip4_query);
  1617. #if IS_ENABLED(CONFIG_IPV6)
  1618. if (!timer_pending(&br->ip6_querier.timer))
  1619. br->ip6_querier.delay_time = jiffies + max_delay;
  1620. br_multicast_start_querier(br, &br->ip6_query);
  1621. #endif
  1622. unlock:
  1623. spin_unlock_bh(&br->multicast_lock);
  1624. return 0;
  1625. }
  1626. int br_multicast_set_hash_max(struct net_bridge *br, unsigned long val)
  1627. {
  1628. int err = -ENOENT;
  1629. u32 old;
  1630. struct net_bridge_mdb_htable *mdb;
  1631. spin_lock(&br->multicast_lock);
  1632. if (!netif_running(br->dev))
  1633. goto unlock;
  1634. err = -EINVAL;
  1635. if (!is_power_of_2(val))
  1636. goto unlock;
  1637. mdb = mlock_dereference(br->mdb, br);
  1638. if (mdb && val < mdb->size)
  1639. goto unlock;
  1640. err = 0;
  1641. old = br->hash_max;
  1642. br->hash_max = val;
  1643. if (mdb) {
  1644. if (mdb->old) {
  1645. err = -EEXIST;
  1646. rollback:
  1647. br->hash_max = old;
  1648. goto unlock;
  1649. }
  1650. err = br_mdb_rehash(&br->mdb, br->hash_max,
  1651. br->hash_elasticity);
  1652. if (err)
  1653. goto rollback;
  1654. }
  1655. unlock:
  1656. spin_unlock(&br->multicast_lock);
  1657. return err;
  1658. }