inet_connection_sock.c 20 KB

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  1. /*
  2. * INET An implementation of the TCP/IP protocol suite for the LINUX
  3. * operating system. INET is implemented using the BSD Socket
  4. * interface as the means of communication with the user level.
  5. *
  6. * Support for INET connection oriented protocols.
  7. *
  8. * Authors: See the TCP sources
  9. *
  10. * This program is free software; you can redistribute it and/or
  11. * modify it under the terms of the GNU General Public License
  12. * as published by the Free Software Foundation; either version
  13. * 2 of the License, or(at your option) any later version.
  14. */
  15. #include <linux/module.h>
  16. #include <linux/jhash.h>
  17. #include <net/inet_connection_sock.h>
  18. #include <net/inet_hashtables.h>
  19. #include <net/inet_timewait_sock.h>
  20. #include <net/ip.h>
  21. #include <net/route.h>
  22. #include <net/tcp_states.h>
  23. #include <net/xfrm.h>
  24. #ifdef INET_CSK_DEBUG
  25. const char inet_csk_timer_bug_msg[] = "inet_csk BUG: unknown timer value\n";
  26. EXPORT_SYMBOL(inet_csk_timer_bug_msg);
  27. #endif
  28. /*
  29. * This struct holds the first and last local port number.
  30. */
  31. struct local_ports sysctl_local_ports __read_mostly = {
  32. .lock = SEQLOCK_UNLOCKED,
  33. .range = { 32768, 61000 },
  34. };
  35. void inet_get_local_port_range(int *low, int *high)
  36. {
  37. unsigned seq;
  38. do {
  39. seq = read_seqbegin(&sysctl_local_ports.lock);
  40. *low = sysctl_local_ports.range[0];
  41. *high = sysctl_local_ports.range[1];
  42. } while (read_seqretry(&sysctl_local_ports.lock, seq));
  43. }
  44. EXPORT_SYMBOL(inet_get_local_port_range);
  45. int inet_csk_bind_conflict(const struct sock *sk,
  46. const struct inet_bind_bucket *tb)
  47. {
  48. const __be32 sk_rcv_saddr = inet_rcv_saddr(sk);
  49. struct sock *sk2;
  50. struct hlist_node *node;
  51. int reuse = sk->sk_reuse;
  52. /*
  53. * Unlike other sk lookup places we do not check
  54. * for sk_net here, since _all_ the socks listed
  55. * in tb->owners list belong to the same net - the
  56. * one this bucket belongs to.
  57. */
  58. sk_for_each_bound(sk2, node, &tb->owners) {
  59. if (sk != sk2 &&
  60. !inet_v6_ipv6only(sk2) &&
  61. (!sk->sk_bound_dev_if ||
  62. !sk2->sk_bound_dev_if ||
  63. sk->sk_bound_dev_if == sk2->sk_bound_dev_if)) {
  64. if (!reuse || !sk2->sk_reuse ||
  65. sk2->sk_state == TCP_LISTEN) {
  66. const __be32 sk2_rcv_saddr = inet_rcv_saddr(sk2);
  67. if (!sk2_rcv_saddr || !sk_rcv_saddr ||
  68. sk2_rcv_saddr == sk_rcv_saddr)
  69. break;
  70. }
  71. }
  72. }
  73. return node != NULL;
  74. }
  75. EXPORT_SYMBOL_GPL(inet_csk_bind_conflict);
  76. /* Obtain a reference to a local port for the given sock,
  77. * if snum is zero it means select any available local port.
  78. */
  79. int inet_csk_get_port(struct sock *sk, unsigned short snum)
  80. {
  81. struct inet_hashinfo *hashinfo = sk->sk_prot->h.hashinfo;
  82. struct inet_bind_hashbucket *head;
  83. struct hlist_node *node;
  84. struct inet_bind_bucket *tb;
  85. int ret, attempts = 5;
  86. struct net *net = sock_net(sk);
  87. int smallest_size = -1, smallest_rover;
  88. local_bh_disable();
  89. if (!snum) {
  90. int remaining, rover, low, high;
  91. again:
  92. inet_get_local_port_range(&low, &high);
  93. remaining = (high - low) + 1;
  94. smallest_rover = rover = net_random() % remaining + low;
  95. smallest_size = -1;
  96. do {
  97. head = &hashinfo->bhash[inet_bhashfn(net, rover,
  98. hashinfo->bhash_size)];
  99. spin_lock(&head->lock);
  100. inet_bind_bucket_for_each(tb, node, &head->chain)
  101. if (ib_net(tb) == net && tb->port == rover) {
  102. if (tb->fastreuse > 0 &&
  103. sk->sk_reuse &&
  104. sk->sk_state != TCP_LISTEN &&
  105. (tb->num_owners < smallest_size || smallest_size == -1)) {
  106. smallest_size = tb->num_owners;
  107. smallest_rover = rover;
  108. if (atomic_read(&hashinfo->bsockets) > (high - low) + 1) {
  109. spin_unlock(&head->lock);
  110. snum = smallest_rover;
  111. goto have_snum;
  112. }
  113. }
  114. goto next;
  115. }
  116. break;
  117. next:
  118. spin_unlock(&head->lock);
  119. if (++rover > high)
  120. rover = low;
  121. } while (--remaining > 0);
  122. /* Exhausted local port range during search? It is not
  123. * possible for us to be holding one of the bind hash
  124. * locks if this test triggers, because if 'remaining'
  125. * drops to zero, we broke out of the do/while loop at
  126. * the top level, not from the 'break;' statement.
  127. */
  128. ret = 1;
  129. if (remaining <= 0) {
  130. if (smallest_size != -1) {
  131. snum = smallest_rover;
  132. goto have_snum;
  133. }
  134. goto fail;
  135. }
  136. /* OK, here is the one we will use. HEAD is
  137. * non-NULL and we hold it's mutex.
  138. */
  139. snum = rover;
  140. } else {
  141. have_snum:
  142. head = &hashinfo->bhash[inet_bhashfn(net, snum,
  143. hashinfo->bhash_size)];
  144. spin_lock(&head->lock);
  145. inet_bind_bucket_for_each(tb, node, &head->chain)
  146. if (ib_net(tb) == net && tb->port == snum)
  147. goto tb_found;
  148. }
  149. tb = NULL;
  150. goto tb_not_found;
  151. tb_found:
  152. if (!hlist_empty(&tb->owners)) {
  153. if (tb->fastreuse > 0 &&
  154. sk->sk_reuse && sk->sk_state != TCP_LISTEN &&
  155. smallest_size == -1) {
  156. goto success;
  157. } else {
  158. ret = 1;
  159. if (inet_csk(sk)->icsk_af_ops->bind_conflict(sk, tb)) {
  160. if (sk->sk_reuse && sk->sk_state != TCP_LISTEN &&
  161. smallest_size != -1 && --attempts >= 0) {
  162. spin_unlock(&head->lock);
  163. goto again;
  164. }
  165. goto fail_unlock;
  166. }
  167. }
  168. }
  169. tb_not_found:
  170. ret = 1;
  171. if (!tb && (tb = inet_bind_bucket_create(hashinfo->bind_bucket_cachep,
  172. net, head, snum)) == NULL)
  173. goto fail_unlock;
  174. if (hlist_empty(&tb->owners)) {
  175. if (sk->sk_reuse && sk->sk_state != TCP_LISTEN)
  176. tb->fastreuse = 1;
  177. else
  178. tb->fastreuse = 0;
  179. } else if (tb->fastreuse &&
  180. (!sk->sk_reuse || sk->sk_state == TCP_LISTEN))
  181. tb->fastreuse = 0;
  182. success:
  183. if (!inet_csk(sk)->icsk_bind_hash)
  184. inet_bind_hash(sk, tb, snum);
  185. WARN_ON(inet_csk(sk)->icsk_bind_hash != tb);
  186. ret = 0;
  187. fail_unlock:
  188. spin_unlock(&head->lock);
  189. fail:
  190. local_bh_enable();
  191. return ret;
  192. }
  193. EXPORT_SYMBOL_GPL(inet_csk_get_port);
  194. /*
  195. * Wait for an incoming connection, avoid race conditions. This must be called
  196. * with the socket locked.
  197. */
  198. static int inet_csk_wait_for_connect(struct sock *sk, long timeo)
  199. {
  200. struct inet_connection_sock *icsk = inet_csk(sk);
  201. DEFINE_WAIT(wait);
  202. int err;
  203. /*
  204. * True wake-one mechanism for incoming connections: only
  205. * one process gets woken up, not the 'whole herd'.
  206. * Since we do not 'race & poll' for established sockets
  207. * anymore, the common case will execute the loop only once.
  208. *
  209. * Subtle issue: "add_wait_queue_exclusive()" will be added
  210. * after any current non-exclusive waiters, and we know that
  211. * it will always _stay_ after any new non-exclusive waiters
  212. * because all non-exclusive waiters are added at the
  213. * beginning of the wait-queue. As such, it's ok to "drop"
  214. * our exclusiveness temporarily when we get woken up without
  215. * having to remove and re-insert us on the wait queue.
  216. */
  217. for (;;) {
  218. prepare_to_wait_exclusive(sk->sk_sleep, &wait,
  219. TASK_INTERRUPTIBLE);
  220. release_sock(sk);
  221. if (reqsk_queue_empty(&icsk->icsk_accept_queue))
  222. timeo = schedule_timeout(timeo);
  223. lock_sock(sk);
  224. err = 0;
  225. if (!reqsk_queue_empty(&icsk->icsk_accept_queue))
  226. break;
  227. err = -EINVAL;
  228. if (sk->sk_state != TCP_LISTEN)
  229. break;
  230. err = sock_intr_errno(timeo);
  231. if (signal_pending(current))
  232. break;
  233. err = -EAGAIN;
  234. if (!timeo)
  235. break;
  236. }
  237. finish_wait(sk->sk_sleep, &wait);
  238. return err;
  239. }
  240. /*
  241. * This will accept the next outstanding connection.
  242. */
  243. struct sock *inet_csk_accept(struct sock *sk, int flags, int *err)
  244. {
  245. struct inet_connection_sock *icsk = inet_csk(sk);
  246. struct sock *newsk;
  247. int error;
  248. lock_sock(sk);
  249. /* We need to make sure that this socket is listening,
  250. * and that it has something pending.
  251. */
  252. error = -EINVAL;
  253. if (sk->sk_state != TCP_LISTEN)
  254. goto out_err;
  255. /* Find already established connection */
  256. if (reqsk_queue_empty(&icsk->icsk_accept_queue)) {
  257. long timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
  258. /* If this is a non blocking socket don't sleep */
  259. error = -EAGAIN;
  260. if (!timeo)
  261. goto out_err;
  262. error = inet_csk_wait_for_connect(sk, timeo);
  263. if (error)
  264. goto out_err;
  265. }
  266. newsk = reqsk_queue_get_child(&icsk->icsk_accept_queue, sk);
  267. WARN_ON(newsk->sk_state == TCP_SYN_RECV);
  268. out:
  269. release_sock(sk);
  270. return newsk;
  271. out_err:
  272. newsk = NULL;
  273. *err = error;
  274. goto out;
  275. }
  276. EXPORT_SYMBOL(inet_csk_accept);
  277. /*
  278. * Using different timers for retransmit, delayed acks and probes
  279. * We may wish use just one timer maintaining a list of expire jiffies
  280. * to optimize.
  281. */
  282. void inet_csk_init_xmit_timers(struct sock *sk,
  283. void (*retransmit_handler)(unsigned long),
  284. void (*delack_handler)(unsigned long),
  285. void (*keepalive_handler)(unsigned long))
  286. {
  287. struct inet_connection_sock *icsk = inet_csk(sk);
  288. setup_timer(&icsk->icsk_retransmit_timer, retransmit_handler,
  289. (unsigned long)sk);
  290. setup_timer(&icsk->icsk_delack_timer, delack_handler,
  291. (unsigned long)sk);
  292. setup_timer(&sk->sk_timer, keepalive_handler, (unsigned long)sk);
  293. icsk->icsk_pending = icsk->icsk_ack.pending = 0;
  294. }
  295. EXPORT_SYMBOL(inet_csk_init_xmit_timers);
  296. void inet_csk_clear_xmit_timers(struct sock *sk)
  297. {
  298. struct inet_connection_sock *icsk = inet_csk(sk);
  299. icsk->icsk_pending = icsk->icsk_ack.pending = icsk->icsk_ack.blocked = 0;
  300. sk_stop_timer(sk, &icsk->icsk_retransmit_timer);
  301. sk_stop_timer(sk, &icsk->icsk_delack_timer);
  302. sk_stop_timer(sk, &sk->sk_timer);
  303. }
  304. EXPORT_SYMBOL(inet_csk_clear_xmit_timers);
  305. void inet_csk_delete_keepalive_timer(struct sock *sk)
  306. {
  307. sk_stop_timer(sk, &sk->sk_timer);
  308. }
  309. EXPORT_SYMBOL(inet_csk_delete_keepalive_timer);
  310. void inet_csk_reset_keepalive_timer(struct sock *sk, unsigned long len)
  311. {
  312. sk_reset_timer(sk, &sk->sk_timer, jiffies + len);
  313. }
  314. EXPORT_SYMBOL(inet_csk_reset_keepalive_timer);
  315. struct dst_entry *inet_csk_route_req(struct sock *sk,
  316. const struct request_sock *req)
  317. {
  318. struct rtable *rt;
  319. const struct inet_request_sock *ireq = inet_rsk(req);
  320. struct ip_options *opt = inet_rsk(req)->opt;
  321. struct flowi fl = { .oif = sk->sk_bound_dev_if,
  322. .nl_u = { .ip4_u =
  323. { .daddr = ((opt && opt->srr) ?
  324. opt->faddr :
  325. ireq->rmt_addr),
  326. .saddr = ireq->loc_addr,
  327. .tos = RT_CONN_FLAGS(sk) } },
  328. .proto = sk->sk_protocol,
  329. .flags = inet_sk_flowi_flags(sk),
  330. .uli_u = { .ports =
  331. { .sport = inet_sk(sk)->sport,
  332. .dport = ireq->rmt_port } } };
  333. struct net *net = sock_net(sk);
  334. security_req_classify_flow(req, &fl);
  335. if (ip_route_output_flow(net, &rt, &fl, sk, 0))
  336. goto no_route;
  337. if (opt && opt->is_strictroute && rt->rt_dst != rt->rt_gateway)
  338. goto route_err;
  339. return &rt->u.dst;
  340. route_err:
  341. ip_rt_put(rt);
  342. no_route:
  343. IP_INC_STATS_BH(net, IPSTATS_MIB_OUTNOROUTES);
  344. return NULL;
  345. }
  346. EXPORT_SYMBOL_GPL(inet_csk_route_req);
  347. static inline u32 inet_synq_hash(const __be32 raddr, const __be16 rport,
  348. const u32 rnd, const u32 synq_hsize)
  349. {
  350. return jhash_2words((__force u32)raddr, (__force u32)rport, rnd) & (synq_hsize - 1);
  351. }
  352. #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
  353. #define AF_INET_FAMILY(fam) ((fam) == AF_INET)
  354. #else
  355. #define AF_INET_FAMILY(fam) 1
  356. #endif
  357. struct request_sock *inet_csk_search_req(const struct sock *sk,
  358. struct request_sock ***prevp,
  359. const __be16 rport, const __be32 raddr,
  360. const __be32 laddr)
  361. {
  362. const struct inet_connection_sock *icsk = inet_csk(sk);
  363. struct listen_sock *lopt = icsk->icsk_accept_queue.listen_opt;
  364. struct request_sock *req, **prev;
  365. for (prev = &lopt->syn_table[inet_synq_hash(raddr, rport, lopt->hash_rnd,
  366. lopt->nr_table_entries)];
  367. (req = *prev) != NULL;
  368. prev = &req->dl_next) {
  369. const struct inet_request_sock *ireq = inet_rsk(req);
  370. if (ireq->rmt_port == rport &&
  371. ireq->rmt_addr == raddr &&
  372. ireq->loc_addr == laddr &&
  373. AF_INET_FAMILY(req->rsk_ops->family)) {
  374. WARN_ON(req->sk);
  375. *prevp = prev;
  376. break;
  377. }
  378. }
  379. return req;
  380. }
  381. EXPORT_SYMBOL_GPL(inet_csk_search_req);
  382. void inet_csk_reqsk_queue_hash_add(struct sock *sk, struct request_sock *req,
  383. unsigned long timeout)
  384. {
  385. struct inet_connection_sock *icsk = inet_csk(sk);
  386. struct listen_sock *lopt = icsk->icsk_accept_queue.listen_opt;
  387. const u32 h = inet_synq_hash(inet_rsk(req)->rmt_addr, inet_rsk(req)->rmt_port,
  388. lopt->hash_rnd, lopt->nr_table_entries);
  389. reqsk_queue_hash_req(&icsk->icsk_accept_queue, h, req, timeout);
  390. inet_csk_reqsk_queue_added(sk, timeout);
  391. }
  392. /* Only thing we need from tcp.h */
  393. extern int sysctl_tcp_synack_retries;
  394. EXPORT_SYMBOL_GPL(inet_csk_reqsk_queue_hash_add);
  395. /* Decide when to expire the request and when to resend SYN-ACK */
  396. static inline void syn_ack_recalc(struct request_sock *req, const int thresh,
  397. const int max_retries,
  398. const u8 rskq_defer_accept,
  399. int *expire, int *resend)
  400. {
  401. if (!rskq_defer_accept) {
  402. *expire = req->retrans >= thresh;
  403. *resend = 1;
  404. return;
  405. }
  406. *expire = req->retrans >= thresh &&
  407. (!inet_rsk(req)->acked || req->retrans >= max_retries);
  408. /*
  409. * Do not resend while waiting for data after ACK,
  410. * start to resend on end of deferring period to give
  411. * last chance for data or ACK to create established socket.
  412. */
  413. *resend = !inet_rsk(req)->acked ||
  414. req->retrans >= rskq_defer_accept - 1;
  415. }
  416. void inet_csk_reqsk_queue_prune(struct sock *parent,
  417. const unsigned long interval,
  418. const unsigned long timeout,
  419. const unsigned long max_rto)
  420. {
  421. struct inet_connection_sock *icsk = inet_csk(parent);
  422. struct request_sock_queue *queue = &icsk->icsk_accept_queue;
  423. struct listen_sock *lopt = queue->listen_opt;
  424. int max_retries = icsk->icsk_syn_retries ? : sysctl_tcp_synack_retries;
  425. int thresh = max_retries;
  426. unsigned long now = jiffies;
  427. struct request_sock **reqp, *req;
  428. int i, budget;
  429. if (lopt == NULL || lopt->qlen == 0)
  430. return;
  431. /* Normally all the openreqs are young and become mature
  432. * (i.e. converted to established socket) for first timeout.
  433. * If synack was not acknowledged for 3 seconds, it means
  434. * one of the following things: synack was lost, ack was lost,
  435. * rtt is high or nobody planned to ack (i.e. synflood).
  436. * When server is a bit loaded, queue is populated with old
  437. * open requests, reducing effective size of queue.
  438. * When server is well loaded, queue size reduces to zero
  439. * after several minutes of work. It is not synflood,
  440. * it is normal operation. The solution is pruning
  441. * too old entries overriding normal timeout, when
  442. * situation becomes dangerous.
  443. *
  444. * Essentially, we reserve half of room for young
  445. * embrions; and abort old ones without pity, if old
  446. * ones are about to clog our table.
  447. */
  448. if (lopt->qlen>>(lopt->max_qlen_log-1)) {
  449. int young = (lopt->qlen_young<<1);
  450. while (thresh > 2) {
  451. if (lopt->qlen < young)
  452. break;
  453. thresh--;
  454. young <<= 1;
  455. }
  456. }
  457. if (queue->rskq_defer_accept)
  458. max_retries = queue->rskq_defer_accept;
  459. budget = 2 * (lopt->nr_table_entries / (timeout / interval));
  460. i = lopt->clock_hand;
  461. do {
  462. reqp=&lopt->syn_table[i];
  463. while ((req = *reqp) != NULL) {
  464. if (time_after_eq(now, req->expires)) {
  465. int expire = 0, resend = 0;
  466. syn_ack_recalc(req, thresh, max_retries,
  467. queue->rskq_defer_accept,
  468. &expire, &resend);
  469. if (!expire &&
  470. (!resend ||
  471. !req->rsk_ops->rtx_syn_ack(parent, req) ||
  472. inet_rsk(req)->acked)) {
  473. unsigned long timeo;
  474. if (req->retrans++ == 0)
  475. lopt->qlen_young--;
  476. timeo = min((timeout << req->retrans), max_rto);
  477. req->expires = now + timeo;
  478. reqp = &req->dl_next;
  479. continue;
  480. }
  481. /* Drop this request */
  482. inet_csk_reqsk_queue_unlink(parent, req, reqp);
  483. reqsk_queue_removed(queue, req);
  484. reqsk_free(req);
  485. continue;
  486. }
  487. reqp = &req->dl_next;
  488. }
  489. i = (i + 1) & (lopt->nr_table_entries - 1);
  490. } while (--budget > 0);
  491. lopt->clock_hand = i;
  492. if (lopt->qlen)
  493. inet_csk_reset_keepalive_timer(parent, interval);
  494. }
  495. EXPORT_SYMBOL_GPL(inet_csk_reqsk_queue_prune);
  496. struct sock *inet_csk_clone(struct sock *sk, const struct request_sock *req,
  497. const gfp_t priority)
  498. {
  499. struct sock *newsk = sk_clone(sk, priority);
  500. if (newsk != NULL) {
  501. struct inet_connection_sock *newicsk = inet_csk(newsk);
  502. newsk->sk_state = TCP_SYN_RECV;
  503. newicsk->icsk_bind_hash = NULL;
  504. inet_sk(newsk)->dport = inet_rsk(req)->rmt_port;
  505. inet_sk(newsk)->num = ntohs(inet_rsk(req)->loc_port);
  506. inet_sk(newsk)->sport = inet_rsk(req)->loc_port;
  507. newsk->sk_write_space = sk_stream_write_space;
  508. newicsk->icsk_retransmits = 0;
  509. newicsk->icsk_backoff = 0;
  510. newicsk->icsk_probes_out = 0;
  511. /* Deinitialize accept_queue to trap illegal accesses. */
  512. memset(&newicsk->icsk_accept_queue, 0, sizeof(newicsk->icsk_accept_queue));
  513. security_inet_csk_clone(newsk, req);
  514. }
  515. return newsk;
  516. }
  517. EXPORT_SYMBOL_GPL(inet_csk_clone);
  518. /*
  519. * At this point, there should be no process reference to this
  520. * socket, and thus no user references at all. Therefore we
  521. * can assume the socket waitqueue is inactive and nobody will
  522. * try to jump onto it.
  523. */
  524. void inet_csk_destroy_sock(struct sock *sk)
  525. {
  526. WARN_ON(sk->sk_state != TCP_CLOSE);
  527. WARN_ON(!sock_flag(sk, SOCK_DEAD));
  528. /* It cannot be in hash table! */
  529. WARN_ON(!sk_unhashed(sk));
  530. /* If it has not 0 inet_sk(sk)->num, it must be bound */
  531. WARN_ON(inet_sk(sk)->num && !inet_csk(sk)->icsk_bind_hash);
  532. sk->sk_prot->destroy(sk);
  533. sk_stream_kill_queues(sk);
  534. xfrm_sk_free_policy(sk);
  535. sk_refcnt_debug_release(sk);
  536. percpu_counter_dec(sk->sk_prot->orphan_count);
  537. sock_put(sk);
  538. }
  539. EXPORT_SYMBOL(inet_csk_destroy_sock);
  540. int inet_csk_listen_start(struct sock *sk, const int nr_table_entries)
  541. {
  542. struct inet_sock *inet = inet_sk(sk);
  543. struct inet_connection_sock *icsk = inet_csk(sk);
  544. int rc = reqsk_queue_alloc(&icsk->icsk_accept_queue, nr_table_entries);
  545. if (rc != 0)
  546. return rc;
  547. sk->sk_max_ack_backlog = 0;
  548. sk->sk_ack_backlog = 0;
  549. inet_csk_delack_init(sk);
  550. /* There is race window here: we announce ourselves listening,
  551. * but this transition is still not validated by get_port().
  552. * It is OK, because this socket enters to hash table only
  553. * after validation is complete.
  554. */
  555. sk->sk_state = TCP_LISTEN;
  556. if (!sk->sk_prot->get_port(sk, inet->num)) {
  557. inet->sport = htons(inet->num);
  558. sk_dst_reset(sk);
  559. sk->sk_prot->hash(sk);
  560. return 0;
  561. }
  562. sk->sk_state = TCP_CLOSE;
  563. __reqsk_queue_destroy(&icsk->icsk_accept_queue);
  564. return -EADDRINUSE;
  565. }
  566. EXPORT_SYMBOL_GPL(inet_csk_listen_start);
  567. /*
  568. * This routine closes sockets which have been at least partially
  569. * opened, but not yet accepted.
  570. */
  571. void inet_csk_listen_stop(struct sock *sk)
  572. {
  573. struct inet_connection_sock *icsk = inet_csk(sk);
  574. struct request_sock *acc_req;
  575. struct request_sock *req;
  576. inet_csk_delete_keepalive_timer(sk);
  577. /* make all the listen_opt local to us */
  578. acc_req = reqsk_queue_yank_acceptq(&icsk->icsk_accept_queue);
  579. /* Following specs, it would be better either to send FIN
  580. * (and enter FIN-WAIT-1, it is normal close)
  581. * or to send active reset (abort).
  582. * Certainly, it is pretty dangerous while synflood, but it is
  583. * bad justification for our negligence 8)
  584. * To be honest, we are not able to make either
  585. * of the variants now. --ANK
  586. */
  587. reqsk_queue_destroy(&icsk->icsk_accept_queue);
  588. while ((req = acc_req) != NULL) {
  589. struct sock *child = req->sk;
  590. acc_req = req->dl_next;
  591. local_bh_disable();
  592. bh_lock_sock(child);
  593. WARN_ON(sock_owned_by_user(child));
  594. sock_hold(child);
  595. sk->sk_prot->disconnect(child, O_NONBLOCK);
  596. sock_orphan(child);
  597. percpu_counter_inc(sk->sk_prot->orphan_count);
  598. inet_csk_destroy_sock(child);
  599. bh_unlock_sock(child);
  600. local_bh_enable();
  601. sock_put(child);
  602. sk_acceptq_removed(sk);
  603. __reqsk_free(req);
  604. }
  605. WARN_ON(sk->sk_ack_backlog);
  606. }
  607. EXPORT_SYMBOL_GPL(inet_csk_listen_stop);
  608. void inet_csk_addr2sockaddr(struct sock *sk, struct sockaddr *uaddr)
  609. {
  610. struct sockaddr_in *sin = (struct sockaddr_in *)uaddr;
  611. const struct inet_sock *inet = inet_sk(sk);
  612. sin->sin_family = AF_INET;
  613. sin->sin_addr.s_addr = inet->daddr;
  614. sin->sin_port = inet->dport;
  615. }
  616. EXPORT_SYMBOL_GPL(inet_csk_addr2sockaddr);
  617. #ifdef CONFIG_COMPAT
  618. int inet_csk_compat_getsockopt(struct sock *sk, int level, int optname,
  619. char __user *optval, int __user *optlen)
  620. {
  621. const struct inet_connection_sock *icsk = inet_csk(sk);
  622. if (icsk->icsk_af_ops->compat_getsockopt != NULL)
  623. return icsk->icsk_af_ops->compat_getsockopt(sk, level, optname,
  624. optval, optlen);
  625. return icsk->icsk_af_ops->getsockopt(sk, level, optname,
  626. optval, optlen);
  627. }
  628. EXPORT_SYMBOL_GPL(inet_csk_compat_getsockopt);
  629. int inet_csk_compat_setsockopt(struct sock *sk, int level, int optname,
  630. char __user *optval, unsigned int optlen)
  631. {
  632. const struct inet_connection_sock *icsk = inet_csk(sk);
  633. if (icsk->icsk_af_ops->compat_setsockopt != NULL)
  634. return icsk->icsk_af_ops->compat_setsockopt(sk, level, optname,
  635. optval, optlen);
  636. return icsk->icsk_af_ops->setsockopt(sk, level, optname,
  637. optval, optlen);
  638. }
  639. EXPORT_SYMBOL_GPL(inet_csk_compat_setsockopt);
  640. #endif