inet_connection_sock.c 21 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. unsigned long *sysctl_local_reserved_ports;
  36. EXPORT_SYMBOL(sysctl_local_reserved_ports);
  37. void inet_get_local_port_range(int *low, int *high)
  38. {
  39. unsigned seq;
  40. do {
  41. seq = read_seqbegin(&sysctl_local_ports.lock);
  42. *low = sysctl_local_ports.range[0];
  43. *high = sysctl_local_ports.range[1];
  44. } while (read_seqretry(&sysctl_local_ports.lock, seq));
  45. }
  46. EXPORT_SYMBOL(inet_get_local_port_range);
  47. int inet_csk_bind_conflict(const struct sock *sk,
  48. const struct inet_bind_bucket *tb)
  49. {
  50. struct sock *sk2;
  51. struct hlist_node *node;
  52. int reuse = sk->sk_reuse;
  53. /*
  54. * Unlike other sk lookup places we do not check
  55. * for sk_net here, since _all_ the socks listed
  56. * in tb->owners list belong to the same net - the
  57. * one this bucket belongs to.
  58. */
  59. sk_for_each_bound(sk2, node, &tb->owners) {
  60. if (sk != sk2 &&
  61. !inet_v6_ipv6only(sk2) &&
  62. (!sk->sk_bound_dev_if ||
  63. !sk2->sk_bound_dev_if ||
  64. sk->sk_bound_dev_if == sk2->sk_bound_dev_if)) {
  65. if (!reuse || !sk2->sk_reuse ||
  66. ((1 << sk2->sk_state) & (TCPF_LISTEN | TCPF_CLOSE))) {
  67. const __be32 sk2_rcv_saddr = sk_rcv_saddr(sk2);
  68. if (!sk2_rcv_saddr || !sk_rcv_saddr(sk) ||
  69. sk2_rcv_saddr == sk_rcv_saddr(sk))
  70. break;
  71. }
  72. }
  73. }
  74. return node != NULL;
  75. }
  76. EXPORT_SYMBOL_GPL(inet_csk_bind_conflict);
  77. /* Obtain a reference to a local port for the given sock,
  78. * if snum is zero it means select any available local port.
  79. */
  80. int inet_csk_get_port(struct sock *sk, unsigned short snum)
  81. {
  82. struct inet_hashinfo *hashinfo = sk->sk_prot->h.hashinfo;
  83. struct inet_bind_hashbucket *head;
  84. struct hlist_node *node;
  85. struct inet_bind_bucket *tb;
  86. int ret, attempts = 5;
  87. struct net *net = sock_net(sk);
  88. int smallest_size = -1, smallest_rover;
  89. local_bh_disable();
  90. if (!snum) {
  91. int remaining, rover, low, high;
  92. again:
  93. inet_get_local_port_range(&low, &high);
  94. remaining = (high - low) + 1;
  95. smallest_rover = rover = net_random() % remaining + low;
  96. smallest_size = -1;
  97. do {
  98. if (inet_is_reserved_local_port(rover))
  99. goto next_nolock;
  100. head = &hashinfo->bhash[inet_bhashfn(net, rover,
  101. hashinfo->bhash_size)];
  102. spin_lock(&head->lock);
  103. inet_bind_bucket_for_each(tb, node, &head->chain)
  104. if (net_eq(ib_net(tb), net) && tb->port == rover) {
  105. if (tb->fastreuse > 0 &&
  106. sk->sk_reuse &&
  107. sk->sk_state != TCP_LISTEN &&
  108. (tb->num_owners < smallest_size || smallest_size == -1)) {
  109. smallest_size = tb->num_owners;
  110. smallest_rover = rover;
  111. if (atomic_read(&hashinfo->bsockets) > (high - low) + 1 &&
  112. !inet_csk(sk)->icsk_af_ops->bind_conflict(sk, tb)) {
  113. spin_unlock(&head->lock);
  114. snum = smallest_rover;
  115. goto have_snum;
  116. }
  117. }
  118. goto next;
  119. }
  120. break;
  121. next:
  122. spin_unlock(&head->lock);
  123. next_nolock:
  124. if (++rover > high)
  125. rover = low;
  126. } while (--remaining > 0);
  127. /* Exhausted local port range during search? It is not
  128. * possible for us to be holding one of the bind hash
  129. * locks if this test triggers, because if 'remaining'
  130. * drops to zero, we broke out of the do/while loop at
  131. * the top level, not from the 'break;' statement.
  132. */
  133. ret = 1;
  134. if (remaining <= 0) {
  135. if (smallest_size != -1) {
  136. snum = smallest_rover;
  137. goto have_snum;
  138. }
  139. goto fail;
  140. }
  141. /* OK, here is the one we will use. HEAD is
  142. * non-NULL and we hold it's mutex.
  143. */
  144. snum = rover;
  145. } else {
  146. have_snum:
  147. head = &hashinfo->bhash[inet_bhashfn(net, snum,
  148. hashinfo->bhash_size)];
  149. spin_lock(&head->lock);
  150. inet_bind_bucket_for_each(tb, node, &head->chain)
  151. if (net_eq(ib_net(tb), net) && tb->port == snum)
  152. goto tb_found;
  153. }
  154. tb = NULL;
  155. goto tb_not_found;
  156. tb_found:
  157. if (!hlist_empty(&tb->owners)) {
  158. if (tb->fastreuse > 0 &&
  159. sk->sk_reuse && sk->sk_state != TCP_LISTEN &&
  160. smallest_size == -1) {
  161. goto success;
  162. } else {
  163. ret = 1;
  164. if (inet_csk(sk)->icsk_af_ops->bind_conflict(sk, tb)) {
  165. if (sk->sk_reuse && sk->sk_state != TCP_LISTEN &&
  166. smallest_size != -1 && --attempts >= 0) {
  167. spin_unlock(&head->lock);
  168. goto again;
  169. }
  170. goto fail_unlock;
  171. }
  172. }
  173. }
  174. tb_not_found:
  175. ret = 1;
  176. if (!tb && (tb = inet_bind_bucket_create(hashinfo->bind_bucket_cachep,
  177. net, head, snum)) == NULL)
  178. goto fail_unlock;
  179. if (hlist_empty(&tb->owners)) {
  180. if (sk->sk_reuse && sk->sk_state != TCP_LISTEN)
  181. tb->fastreuse = 1;
  182. else
  183. tb->fastreuse = 0;
  184. } else if (tb->fastreuse &&
  185. (!sk->sk_reuse || sk->sk_state == TCP_LISTEN))
  186. tb->fastreuse = 0;
  187. success:
  188. if (!inet_csk(sk)->icsk_bind_hash)
  189. inet_bind_hash(sk, tb, snum);
  190. WARN_ON(inet_csk(sk)->icsk_bind_hash != tb);
  191. ret = 0;
  192. fail_unlock:
  193. spin_unlock(&head->lock);
  194. fail:
  195. local_bh_enable();
  196. return ret;
  197. }
  198. EXPORT_SYMBOL_GPL(inet_csk_get_port);
  199. /*
  200. * Wait for an incoming connection, avoid race conditions. This must be called
  201. * with the socket locked.
  202. */
  203. static int inet_csk_wait_for_connect(struct sock *sk, long timeo)
  204. {
  205. struct inet_connection_sock *icsk = inet_csk(sk);
  206. DEFINE_WAIT(wait);
  207. int err;
  208. /*
  209. * True wake-one mechanism for incoming connections: only
  210. * one process gets woken up, not the 'whole herd'.
  211. * Since we do not 'race & poll' for established sockets
  212. * anymore, the common case will execute the loop only once.
  213. *
  214. * Subtle issue: "add_wait_queue_exclusive()" will be added
  215. * after any current non-exclusive waiters, and we know that
  216. * it will always _stay_ after any new non-exclusive waiters
  217. * because all non-exclusive waiters are added at the
  218. * beginning of the wait-queue. As such, it's ok to "drop"
  219. * our exclusiveness temporarily when we get woken up without
  220. * having to remove and re-insert us on the wait queue.
  221. */
  222. for (;;) {
  223. prepare_to_wait_exclusive(sk_sleep(sk), &wait,
  224. TASK_INTERRUPTIBLE);
  225. release_sock(sk);
  226. if (reqsk_queue_empty(&icsk->icsk_accept_queue))
  227. timeo = schedule_timeout(timeo);
  228. lock_sock(sk);
  229. err = 0;
  230. if (!reqsk_queue_empty(&icsk->icsk_accept_queue))
  231. break;
  232. err = -EINVAL;
  233. if (sk->sk_state != TCP_LISTEN)
  234. break;
  235. err = sock_intr_errno(timeo);
  236. if (signal_pending(current))
  237. break;
  238. err = -EAGAIN;
  239. if (!timeo)
  240. break;
  241. }
  242. finish_wait(sk_sleep(sk), &wait);
  243. return err;
  244. }
  245. /*
  246. * This will accept the next outstanding connection.
  247. */
  248. struct sock *inet_csk_accept(struct sock *sk, int flags, int *err)
  249. {
  250. struct inet_connection_sock *icsk = inet_csk(sk);
  251. struct sock *newsk;
  252. int error;
  253. lock_sock(sk);
  254. /* We need to make sure that this socket is listening,
  255. * and that it has something pending.
  256. */
  257. error = -EINVAL;
  258. if (sk->sk_state != TCP_LISTEN)
  259. goto out_err;
  260. /* Find already established connection */
  261. if (reqsk_queue_empty(&icsk->icsk_accept_queue)) {
  262. long timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
  263. /* If this is a non blocking socket don't sleep */
  264. error = -EAGAIN;
  265. if (!timeo)
  266. goto out_err;
  267. error = inet_csk_wait_for_connect(sk, timeo);
  268. if (error)
  269. goto out_err;
  270. }
  271. newsk = reqsk_queue_get_child(&icsk->icsk_accept_queue, sk);
  272. WARN_ON(newsk->sk_state == TCP_SYN_RECV);
  273. out:
  274. release_sock(sk);
  275. return newsk;
  276. out_err:
  277. newsk = NULL;
  278. *err = error;
  279. goto out;
  280. }
  281. EXPORT_SYMBOL(inet_csk_accept);
  282. /*
  283. * Using different timers for retransmit, delayed acks and probes
  284. * We may wish use just one timer maintaining a list of expire jiffies
  285. * to optimize.
  286. */
  287. void inet_csk_init_xmit_timers(struct sock *sk,
  288. void (*retransmit_handler)(unsigned long),
  289. void (*delack_handler)(unsigned long),
  290. void (*keepalive_handler)(unsigned long))
  291. {
  292. struct inet_connection_sock *icsk = inet_csk(sk);
  293. setup_timer(&icsk->icsk_retransmit_timer, retransmit_handler,
  294. (unsigned long)sk);
  295. setup_timer(&icsk->icsk_delack_timer, delack_handler,
  296. (unsigned long)sk);
  297. setup_timer(&sk->sk_timer, keepalive_handler, (unsigned long)sk);
  298. icsk->icsk_pending = icsk->icsk_ack.pending = 0;
  299. }
  300. EXPORT_SYMBOL(inet_csk_init_xmit_timers);
  301. void inet_csk_clear_xmit_timers(struct sock *sk)
  302. {
  303. struct inet_connection_sock *icsk = inet_csk(sk);
  304. icsk->icsk_pending = icsk->icsk_ack.pending = icsk->icsk_ack.blocked = 0;
  305. sk_stop_timer(sk, &icsk->icsk_retransmit_timer);
  306. sk_stop_timer(sk, &icsk->icsk_delack_timer);
  307. sk_stop_timer(sk, &sk->sk_timer);
  308. }
  309. EXPORT_SYMBOL(inet_csk_clear_xmit_timers);
  310. void inet_csk_delete_keepalive_timer(struct sock *sk)
  311. {
  312. sk_stop_timer(sk, &sk->sk_timer);
  313. }
  314. EXPORT_SYMBOL(inet_csk_delete_keepalive_timer);
  315. void inet_csk_reset_keepalive_timer(struct sock *sk, unsigned long len)
  316. {
  317. sk_reset_timer(sk, &sk->sk_timer, jiffies + len);
  318. }
  319. EXPORT_SYMBOL(inet_csk_reset_keepalive_timer);
  320. struct dst_entry *inet_csk_route_req(struct sock *sk,
  321. const struct request_sock *req)
  322. {
  323. struct rtable *rt;
  324. const struct inet_request_sock *ireq = inet_rsk(req);
  325. struct ip_options *opt = inet_rsk(req)->opt;
  326. struct flowi fl = { .oif = sk->sk_bound_dev_if,
  327. .mark = sk->sk_mark,
  328. .fl4_dst = ((opt && opt->srr) ?
  329. opt->faddr : ireq->rmt_addr),
  330. .fl4_src = ireq->loc_addr,
  331. .fl4_tos = RT_CONN_FLAGS(sk),
  332. .proto = sk->sk_protocol,
  333. .flags = inet_sk_flowi_flags(sk),
  334. .fl_ip_sport = inet_sk(sk)->inet_sport,
  335. .fl_ip_dport = ireq->rmt_port };
  336. struct net *net = sock_net(sk);
  337. security_req_classify_flow(req, &fl);
  338. if (ip_route_output_flow(net, &rt, &fl, sk, 0))
  339. goto no_route;
  340. if (opt && opt->is_strictroute && rt->rt_dst != rt->rt_gateway)
  341. goto route_err;
  342. return &rt->dst;
  343. route_err:
  344. ip_rt_put(rt);
  345. no_route:
  346. IP_INC_STATS_BH(net, IPSTATS_MIB_OUTNOROUTES);
  347. return NULL;
  348. }
  349. EXPORT_SYMBOL_GPL(inet_csk_route_req);
  350. static inline u32 inet_synq_hash(const __be32 raddr, const __be16 rport,
  351. const u32 rnd, const u32 synq_hsize)
  352. {
  353. return jhash_2words((__force u32)raddr, (__force u32)rport, rnd) & (synq_hsize - 1);
  354. }
  355. #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
  356. #define AF_INET_FAMILY(fam) ((fam) == AF_INET)
  357. #else
  358. #define AF_INET_FAMILY(fam) 1
  359. #endif
  360. struct request_sock *inet_csk_search_req(const struct sock *sk,
  361. struct request_sock ***prevp,
  362. const __be16 rport, const __be32 raddr,
  363. const __be32 laddr)
  364. {
  365. const struct inet_connection_sock *icsk = inet_csk(sk);
  366. struct listen_sock *lopt = icsk->icsk_accept_queue.listen_opt;
  367. struct request_sock *req, **prev;
  368. for (prev = &lopt->syn_table[inet_synq_hash(raddr, rport, lopt->hash_rnd,
  369. lopt->nr_table_entries)];
  370. (req = *prev) != NULL;
  371. prev = &req->dl_next) {
  372. const struct inet_request_sock *ireq = inet_rsk(req);
  373. if (ireq->rmt_port == rport &&
  374. ireq->rmt_addr == raddr &&
  375. ireq->loc_addr == laddr &&
  376. AF_INET_FAMILY(req->rsk_ops->family)) {
  377. WARN_ON(req->sk);
  378. *prevp = prev;
  379. break;
  380. }
  381. }
  382. return req;
  383. }
  384. EXPORT_SYMBOL_GPL(inet_csk_search_req);
  385. void inet_csk_reqsk_queue_hash_add(struct sock *sk, struct request_sock *req,
  386. unsigned long timeout)
  387. {
  388. struct inet_connection_sock *icsk = inet_csk(sk);
  389. struct listen_sock *lopt = icsk->icsk_accept_queue.listen_opt;
  390. const u32 h = inet_synq_hash(inet_rsk(req)->rmt_addr, inet_rsk(req)->rmt_port,
  391. lopt->hash_rnd, lopt->nr_table_entries);
  392. reqsk_queue_hash_req(&icsk->icsk_accept_queue, h, req, timeout);
  393. inet_csk_reqsk_queue_added(sk, timeout);
  394. }
  395. EXPORT_SYMBOL_GPL(inet_csk_reqsk_queue_hash_add);
  396. /* Only thing we need from tcp.h */
  397. extern int sysctl_tcp_synack_retries;
  398. /* Decide when to expire the request and when to resend SYN-ACK */
  399. static inline void syn_ack_recalc(struct request_sock *req, const int thresh,
  400. const int max_retries,
  401. const u8 rskq_defer_accept,
  402. int *expire, int *resend)
  403. {
  404. if (!rskq_defer_accept) {
  405. *expire = req->retrans >= thresh;
  406. *resend = 1;
  407. return;
  408. }
  409. *expire = req->retrans >= thresh &&
  410. (!inet_rsk(req)->acked || req->retrans >= max_retries);
  411. /*
  412. * Do not resend while waiting for data after ACK,
  413. * start to resend on end of deferring period to give
  414. * last chance for data or ACK to create established socket.
  415. */
  416. *resend = !inet_rsk(req)->acked ||
  417. req->retrans >= rskq_defer_accept - 1;
  418. }
  419. void inet_csk_reqsk_queue_prune(struct sock *parent,
  420. const unsigned long interval,
  421. const unsigned long timeout,
  422. const unsigned long max_rto)
  423. {
  424. struct inet_connection_sock *icsk = inet_csk(parent);
  425. struct request_sock_queue *queue = &icsk->icsk_accept_queue;
  426. struct listen_sock *lopt = queue->listen_opt;
  427. int max_retries = icsk->icsk_syn_retries ? : sysctl_tcp_synack_retries;
  428. int thresh = max_retries;
  429. unsigned long now = jiffies;
  430. struct request_sock **reqp, *req;
  431. int i, budget;
  432. if (lopt == NULL || lopt->qlen == 0)
  433. return;
  434. /* Normally all the openreqs are young and become mature
  435. * (i.e. converted to established socket) for first timeout.
  436. * If synack was not acknowledged for 3 seconds, it means
  437. * one of the following things: synack was lost, ack was lost,
  438. * rtt is high or nobody planned to ack (i.e. synflood).
  439. * When server is a bit loaded, queue is populated with old
  440. * open requests, reducing effective size of queue.
  441. * When server is well loaded, queue size reduces to zero
  442. * after several minutes of work. It is not synflood,
  443. * it is normal operation. The solution is pruning
  444. * too old entries overriding normal timeout, when
  445. * situation becomes dangerous.
  446. *
  447. * Essentially, we reserve half of room for young
  448. * embrions; and abort old ones without pity, if old
  449. * ones are about to clog our table.
  450. */
  451. if (lopt->qlen>>(lopt->max_qlen_log-1)) {
  452. int young = (lopt->qlen_young<<1);
  453. while (thresh > 2) {
  454. if (lopt->qlen < young)
  455. break;
  456. thresh--;
  457. young <<= 1;
  458. }
  459. }
  460. if (queue->rskq_defer_accept)
  461. max_retries = queue->rskq_defer_accept;
  462. budget = 2 * (lopt->nr_table_entries / (timeout / interval));
  463. i = lopt->clock_hand;
  464. do {
  465. reqp=&lopt->syn_table[i];
  466. while ((req = *reqp) != NULL) {
  467. if (time_after_eq(now, req->expires)) {
  468. int expire = 0, resend = 0;
  469. syn_ack_recalc(req, thresh, max_retries,
  470. queue->rskq_defer_accept,
  471. &expire, &resend);
  472. if (req->rsk_ops->syn_ack_timeout)
  473. req->rsk_ops->syn_ack_timeout(parent, req);
  474. if (!expire &&
  475. (!resend ||
  476. !req->rsk_ops->rtx_syn_ack(parent, req, NULL) ||
  477. inet_rsk(req)->acked)) {
  478. unsigned long timeo;
  479. if (req->retrans++ == 0)
  480. lopt->qlen_young--;
  481. timeo = min((timeout << req->retrans), max_rto);
  482. req->expires = now + timeo;
  483. reqp = &req->dl_next;
  484. continue;
  485. }
  486. /* Drop this request */
  487. inet_csk_reqsk_queue_unlink(parent, req, reqp);
  488. reqsk_queue_removed(queue, req);
  489. reqsk_free(req);
  490. continue;
  491. }
  492. reqp = &req->dl_next;
  493. }
  494. i = (i + 1) & (lopt->nr_table_entries - 1);
  495. } while (--budget > 0);
  496. lopt->clock_hand = i;
  497. if (lopt->qlen)
  498. inet_csk_reset_keepalive_timer(parent, interval);
  499. }
  500. EXPORT_SYMBOL_GPL(inet_csk_reqsk_queue_prune);
  501. struct sock *inet_csk_clone(struct sock *sk, const struct request_sock *req,
  502. const gfp_t priority)
  503. {
  504. struct sock *newsk = sk_clone(sk, priority);
  505. if (newsk != NULL) {
  506. struct inet_connection_sock *newicsk = inet_csk(newsk);
  507. newsk->sk_state = TCP_SYN_RECV;
  508. newicsk->icsk_bind_hash = NULL;
  509. inet_sk(newsk)->inet_dport = inet_rsk(req)->rmt_port;
  510. inet_sk(newsk)->inet_num = ntohs(inet_rsk(req)->loc_port);
  511. inet_sk(newsk)->inet_sport = inet_rsk(req)->loc_port;
  512. newsk->sk_write_space = sk_stream_write_space;
  513. newicsk->icsk_retransmits = 0;
  514. newicsk->icsk_backoff = 0;
  515. newicsk->icsk_probes_out = 0;
  516. /* Deinitialize accept_queue to trap illegal accesses. */
  517. memset(&newicsk->icsk_accept_queue, 0, sizeof(newicsk->icsk_accept_queue));
  518. security_inet_csk_clone(newsk, req);
  519. }
  520. return newsk;
  521. }
  522. EXPORT_SYMBOL_GPL(inet_csk_clone);
  523. /*
  524. * At this point, there should be no process reference to this
  525. * socket, and thus no user references at all. Therefore we
  526. * can assume the socket waitqueue is inactive and nobody will
  527. * try to jump onto it.
  528. */
  529. void inet_csk_destroy_sock(struct sock *sk)
  530. {
  531. WARN_ON(sk->sk_state != TCP_CLOSE);
  532. WARN_ON(!sock_flag(sk, SOCK_DEAD));
  533. /* It cannot be in hash table! */
  534. WARN_ON(!sk_unhashed(sk));
  535. /* If it has not 0 inet_sk(sk)->inet_num, it must be bound */
  536. WARN_ON(inet_sk(sk)->inet_num && !inet_csk(sk)->icsk_bind_hash);
  537. sk->sk_prot->destroy(sk);
  538. sk_stream_kill_queues(sk);
  539. xfrm_sk_free_policy(sk);
  540. sk_refcnt_debug_release(sk);
  541. percpu_counter_dec(sk->sk_prot->orphan_count);
  542. sock_put(sk);
  543. }
  544. EXPORT_SYMBOL(inet_csk_destroy_sock);
  545. int inet_csk_listen_start(struct sock *sk, const int nr_table_entries)
  546. {
  547. struct inet_sock *inet = inet_sk(sk);
  548. struct inet_connection_sock *icsk = inet_csk(sk);
  549. int rc = reqsk_queue_alloc(&icsk->icsk_accept_queue, nr_table_entries);
  550. if (rc != 0)
  551. return rc;
  552. sk->sk_max_ack_backlog = 0;
  553. sk->sk_ack_backlog = 0;
  554. inet_csk_delack_init(sk);
  555. /* There is race window here: we announce ourselves listening,
  556. * but this transition is still not validated by get_port().
  557. * It is OK, because this socket enters to hash table only
  558. * after validation is complete.
  559. */
  560. sk->sk_state = TCP_LISTEN;
  561. if (!sk->sk_prot->get_port(sk, inet->inet_num)) {
  562. inet->inet_sport = htons(inet->inet_num);
  563. sk_dst_reset(sk);
  564. sk->sk_prot->hash(sk);
  565. return 0;
  566. }
  567. sk->sk_state = TCP_CLOSE;
  568. __reqsk_queue_destroy(&icsk->icsk_accept_queue);
  569. return -EADDRINUSE;
  570. }
  571. EXPORT_SYMBOL_GPL(inet_csk_listen_start);
  572. /*
  573. * This routine closes sockets which have been at least partially
  574. * opened, but not yet accepted.
  575. */
  576. void inet_csk_listen_stop(struct sock *sk)
  577. {
  578. struct inet_connection_sock *icsk = inet_csk(sk);
  579. struct request_sock *acc_req;
  580. struct request_sock *req;
  581. inet_csk_delete_keepalive_timer(sk);
  582. /* make all the listen_opt local to us */
  583. acc_req = reqsk_queue_yank_acceptq(&icsk->icsk_accept_queue);
  584. /* Following specs, it would be better either to send FIN
  585. * (and enter FIN-WAIT-1, it is normal close)
  586. * or to send active reset (abort).
  587. * Certainly, it is pretty dangerous while synflood, but it is
  588. * bad justification for our negligence 8)
  589. * To be honest, we are not able to make either
  590. * of the variants now. --ANK
  591. */
  592. reqsk_queue_destroy(&icsk->icsk_accept_queue);
  593. while ((req = acc_req) != NULL) {
  594. struct sock *child = req->sk;
  595. acc_req = req->dl_next;
  596. local_bh_disable();
  597. bh_lock_sock(child);
  598. WARN_ON(sock_owned_by_user(child));
  599. sock_hold(child);
  600. sk->sk_prot->disconnect(child, O_NONBLOCK);
  601. sock_orphan(child);
  602. percpu_counter_inc(sk->sk_prot->orphan_count);
  603. inet_csk_destroy_sock(child);
  604. bh_unlock_sock(child);
  605. local_bh_enable();
  606. sock_put(child);
  607. sk_acceptq_removed(sk);
  608. __reqsk_free(req);
  609. }
  610. WARN_ON(sk->sk_ack_backlog);
  611. }
  612. EXPORT_SYMBOL_GPL(inet_csk_listen_stop);
  613. void inet_csk_addr2sockaddr(struct sock *sk, struct sockaddr *uaddr)
  614. {
  615. struct sockaddr_in *sin = (struct sockaddr_in *)uaddr;
  616. const struct inet_sock *inet = inet_sk(sk);
  617. sin->sin_family = AF_INET;
  618. sin->sin_addr.s_addr = inet->inet_daddr;
  619. sin->sin_port = inet->inet_dport;
  620. }
  621. EXPORT_SYMBOL_GPL(inet_csk_addr2sockaddr);
  622. #ifdef CONFIG_COMPAT
  623. int inet_csk_compat_getsockopt(struct sock *sk, int level, int optname,
  624. char __user *optval, int __user *optlen)
  625. {
  626. const struct inet_connection_sock *icsk = inet_csk(sk);
  627. if (icsk->icsk_af_ops->compat_getsockopt != NULL)
  628. return icsk->icsk_af_ops->compat_getsockopt(sk, level, optname,
  629. optval, optlen);
  630. return icsk->icsk_af_ops->getsockopt(sk, level, optname,
  631. optval, optlen);
  632. }
  633. EXPORT_SYMBOL_GPL(inet_csk_compat_getsockopt);
  634. int inet_csk_compat_setsockopt(struct sock *sk, int level, int optname,
  635. char __user *optval, unsigned int optlen)
  636. {
  637. const struct inet_connection_sock *icsk = inet_csk(sk);
  638. if (icsk->icsk_af_ops->compat_setsockopt != NULL)
  639. return icsk->icsk_af_ops->compat_setsockopt(sk, level, optname,
  640. optval, optlen);
  641. return icsk->icsk_af_ops->setsockopt(sk, level, optname,
  642. optval, optlen);
  643. }
  644. EXPORT_SYMBOL_GPL(inet_csk_compat_setsockopt);
  645. #endif