git.oblomov.eu Git - linux-2.6/blob - net/ipv4/inet_connection_sock.c

   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
  16 #include <linux/module.h>
  17 #include <linux/jhash.h>
  18
  19 #include <net/inet_connection_sock.h>
  20 #include <net/inet_hashtables.h>
  21 #include <net/inet_timewait_sock.h>
  22 #include <net/ip.h>
  23 #include <net/route.h>
  24 #include <net/tcp_states.h>
  25 #include <net/xfrm.h>
  26
  27 #ifdef INET_CSK_DEBUG
  28 const char inet_csk_timer_bug_msg[] = "inet_csk BUG: unknown timer value\n";
  29 EXPORT_SYMBOL(inet_csk_timer_bug_msg);
  30 #endif
  31
  32 /*
  33  * This array holds the first and last local port number.
  34  */
  35 int sysctl_local_port_range[2] = { 32768, 61000 };
  36
  37 int inet_csk_bind_conflict(const struct sock *sk,
  38                            const struct inet_bind_bucket *tb)
  39 {
  40         const __be32 sk_rcv_saddr = inet_rcv_saddr(sk);
  41         struct sock *sk2;
  42         struct hlist_node *node;
  43         int reuse = sk->sk_reuse;
  44
  45         sk_for_each_bound(sk2, node, &tb->owners) {
  46                 if (sk != sk2 &&
  47                     !inet_v6_ipv6only(sk2) &&
  48                     (!sk->sk_bound_dev_if ||
  49                      !sk2->sk_bound_dev_if ||
  50                      sk->sk_bound_dev_if == sk2->sk_bound_dev_if)) {
  51                         if (!reuse || !sk2->sk_reuse ||
  52                             sk2->sk_state == TCP_LISTEN) {
  53                                 const __be32 sk2_rcv_saddr = inet_rcv_saddr(sk2);
  54                                 if (!sk2_rcv_saddr || !sk_rcv_saddr ||
  55                                     sk2_rcv_saddr == sk_rcv_saddr)
  56                                         break;
  57                         }
  58                 }
  59         }
  60         return node != NULL;
  61 }
  62
  63 EXPORT_SYMBOL_GPL(inet_csk_bind_conflict);
  64
  65 /* Obtain a reference to a local port for the given sock,
  66  * if snum is zero it means select any available local port.
  67  */
  68 int inet_csk_get_port(struct inet_hashinfo *hashinfo,
  69                       struct sock *sk, unsigned short snum,
  70                       int (*bind_conflict)(const struct sock *sk,
  71                                            const struct inet_bind_bucket *tb))
  72 {
  73         struct inet_bind_hashbucket *head;
  74         struct hlist_node *node;
  75         struct inet_bind_bucket *tb;
  76         int ret;
  77
  78         local_bh_disable();
  79         if (!snum) {
  80                 int low = sysctl_local_port_range[0];
  81                 int high = sysctl_local_port_range[1];
  82                 int remaining = (high - low) + 1;
  83                 int rover = net_random() % (high - low) + low;
  84
  85                 do {
  86                         head = &hashinfo->bhash[inet_bhashfn(rover, hashinfo->bhash_size)];
  87                         spin_lock(&head->lock);
  88                         inet_bind_bucket_for_each(tb, node, &head->chain)
  89                                 if (tb->port == rover)
  90                                         goto next;
  91                         break;
  92                 next:
  93                         spin_unlock(&head->lock);
  94                         if (++rover > high)
  95                                 rover = low;
  96                 } while (--remaining > 0);
  97
  98                 /* Exhausted local port range during search?  It is not
  99                  * possible for us to be holding one of the bind hash
 100                  * locks if this test triggers, because if 'remaining'
 101                  * drops to zero, we broke out of the do/while loop at
 102                  * the top level, not from the 'break;' statement.
 103                  */
 104                 ret = 1;
 105                 if (remaining <= 0)
 106                         goto fail;
 107
 108                 /* OK, here is the one we will use.  HEAD is
 109                  * non-NULL and we hold it's mutex.
 110                  */
 111                 snum = rover;
 112         } else {
 113                 head = &hashinfo->bhash[inet_bhashfn(snum, hashinfo->bhash_size)];
 114                 spin_lock(&head->lock);
 115                 inet_bind_bucket_for_each(tb, node, &head->chain)
 116                         if (tb->port == snum)
 117                                 goto tb_found;
 118         }
 119         tb = NULL;
 120         goto tb_not_found;
 121 tb_found:
 122         if (!hlist_empty(&tb->owners)) {
 123                 if (sk->sk_reuse > 1)
 124                         goto success;
 125                 if (tb->fastreuse > 0 &&
 126                     sk->sk_reuse && sk->sk_state != TCP_LISTEN) {
 127                         goto success;
 128                 } else {
 129                         ret = 1;
 130                         if (bind_conflict(sk, tb))
 131                                 goto fail_unlock;
 132                 }
 133         }
 134 tb_not_found:
 135         ret = 1;
 136         if (!tb && (tb = inet_bind_bucket_create(hashinfo->bind_bucket_cachep, head, snum)) == NULL)
 137                 goto fail_unlock;
 138         if (hlist_empty(&tb->owners)) {
 139                 if (sk->sk_reuse && sk->sk_state != TCP_LISTEN)
 140                         tb->fastreuse = 1;
 141                 else
 142                         tb->fastreuse = 0;
 143         } else if (tb->fastreuse &&
 144                    (!sk->sk_reuse || sk->sk_state == TCP_LISTEN))
 145                 tb->fastreuse = 0;
 146 success:
 147         if (!inet_csk(sk)->icsk_bind_hash)
 148                 inet_bind_hash(sk, tb, snum);
 149         BUG_TRAP(inet_csk(sk)->icsk_bind_hash == tb);
 150         ret = 0;
 151
 152 fail_unlock:
 153         spin_unlock(&head->lock);
 154 fail:
 155         local_bh_enable();
 156         return ret;
 157 }
 158
 159 EXPORT_SYMBOL_GPL(inet_csk_get_port);
 160
 161 /*
 162  * Wait for an incoming connection, avoid race conditions. This must be called
 163  * with the socket locked.
 164  */
 165 static int inet_csk_wait_for_connect(struct sock *sk, long timeo)
 166 {
 167         struct inet_connection_sock *icsk = inet_csk(sk);
 168         DEFINE_WAIT(wait);
 169         int err;
 170
 171         /*
 172          * True wake-one mechanism for incoming connections: only
 173          * one process gets woken up, not the 'whole herd'.
 174          * Since we do not 'race & poll' for established sockets
 175          * anymore, the common case will execute the loop only once.
 176          *
 177          * Subtle issue: "add_wait_queue_exclusive()" will be added
 178          * after any current non-exclusive waiters, and we know that
 179          * it will always _stay_ after any new non-exclusive waiters
 180          * because all non-exclusive waiters are added at the
 181          * beginning of the wait-queue. As such, it's ok to "drop"
 182          * our exclusiveness temporarily when we get woken up without
 183          * having to remove and re-insert us on the wait queue.
 184          */
 185         for (;;) {
 186                 prepare_to_wait_exclusive(sk->sk_sleep, &wait,
 187                                           TASK_INTERRUPTIBLE);
 188                 release_sock(sk);
 189                 if (reqsk_queue_empty(&icsk->icsk_accept_queue))
 190                         timeo = schedule_timeout(timeo);
 191                 lock_sock(sk);
 192                 err = 0;
 193                 if (!reqsk_queue_empty(&icsk->icsk_accept_queue))
 194                         break;
 195                 err = -EINVAL;
 196                 if (sk->sk_state != TCP_LISTEN)
 197                         break;
 198                 err = sock_intr_errno(timeo);
 199                 if (signal_pending(current))
 200                         break;
 201                 err = -EAGAIN;
 202                 if (!timeo)
 203                         break;
 204         }
 205         finish_wait(sk->sk_sleep, &wait);
 206         return err;
 207 }
 208
 209 /*
 210  * This will accept the next outstanding connection.
 211  */
 212 struct sock *inet_csk_accept(struct sock *sk, int flags, int *err)
 213 {
 214         struct inet_connection_sock *icsk = inet_csk(sk);
 215         struct sock *newsk;
 216         int error;
 217
 218         lock_sock(sk);
 219
 220         /* We need to make sure that this socket is listening,
 221          * and that it has something pending.
 222          */
 223         error = -EINVAL;
 224         if (sk->sk_state != TCP_LISTEN)
 225                 goto out_err;
 226
 227         /* Find already established connection */
 228         if (reqsk_queue_empty(&icsk->icsk_accept_queue)) {
 229                 long timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
 230
 231                 /* If this is a non blocking socket don't sleep */
 232                 error = -EAGAIN;
 233                 if (!timeo)
 234                         goto out_err;
 235
 236                 error = inet_csk_wait_for_connect(sk, timeo);
 237                 if (error)
 238                         goto out_err;
 239         }
 240
 241         newsk = reqsk_queue_get_child(&icsk->icsk_accept_queue, sk);
 242         BUG_TRAP(newsk->sk_state != TCP_SYN_RECV);
 243 out:
 244         release_sock(sk);
 245         return newsk;
 246 out_err:
 247         newsk = NULL;
 248         *err = error;
 249         goto out;
 250 }
 251
 252 EXPORT_SYMBOL(inet_csk_accept);
 253
 254 /*
 255  * Using different timers for retransmit, delayed acks and probes
 256  * We may wish use just one timer maintaining a list of expire jiffies
 257  * to optimize.
 258  */
 259 void inet_csk_init_xmit_timers(struct sock *sk,
 260                                void (*retransmit_handler)(unsigned long),
 261                                void (*delack_handler)(unsigned long),
 262                                void (*keepalive_handler)(unsigned long))
 263 {
 264         struct inet_connection_sock *icsk = inet_csk(sk);
 265
 266         init_timer(&icsk->icsk_retransmit_timer);
 267         init_timer(&icsk->icsk_delack_timer);
 268         init_timer(&sk->sk_timer);
 269
 270         icsk->icsk_retransmit_timer.function = retransmit_handler;
 271         icsk->icsk_delack_timer.function     = delack_handler;
 272         sk->sk_timer.function                = keepalive_handler;
 273
 274         icsk->icsk_retransmit_timer.data =
 275                 icsk->icsk_delack_timer.data =
 276                         sk->sk_timer.data  = (unsigned long)sk;
 277
 278         icsk->icsk_pending = icsk->icsk_ack.pending = 0;
 279 }
 280
 281 EXPORT_SYMBOL(inet_csk_init_xmit_timers);
 282
 283 void inet_csk_clear_xmit_timers(struct sock *sk)
 284 {
 285         struct inet_connection_sock *icsk = inet_csk(sk);
 286
 287         icsk->icsk_pending = icsk->icsk_ack.pending = icsk->icsk_ack.blocked = 0;
 288
 289         sk_stop_timer(sk, &icsk->icsk_retransmit_timer);
 290         sk_stop_timer(sk, &icsk->icsk_delack_timer);
 291         sk_stop_timer(sk, &sk->sk_timer);
 292 }
 293
 294 EXPORT_SYMBOL(inet_csk_clear_xmit_timers);
 295
 296 void inet_csk_delete_keepalive_timer(struct sock *sk)
 297 {
 298         sk_stop_timer(sk, &sk->sk_timer);
 299 }
 300
 301 EXPORT_SYMBOL(inet_csk_delete_keepalive_timer);
 302
 303 void inet_csk_reset_keepalive_timer(struct sock *sk, unsigned long len)
 304 {
 305         sk_reset_timer(sk, &sk->sk_timer, jiffies + len);
 306 }
 307
 308 EXPORT_SYMBOL(inet_csk_reset_keepalive_timer);
 309
 310 struct dst_entry* inet_csk_route_req(struct sock *sk,
 311                                      const struct request_sock *req)
 312 {
 313         struct rtable *rt;
 314         const struct inet_request_sock *ireq = inet_rsk(req);
 315         struct ip_options *opt = inet_rsk(req)->opt;
 316         struct flowi fl = { .oif = sk->sk_bound_dev_if,
 317                             .nl_u = { .ip4_u =
 318                                       { .daddr = ((opt && opt->srr) ?
 319                                                   opt->faddr :
 320                                                   ireq->rmt_addr),
 321                                         .saddr = ireq->loc_addr,
 322                                         .tos = RT_CONN_FLAGS(sk) } },
 323                             .proto = sk->sk_protocol,
 324                             .uli_u = { .ports =
 325                                        { .sport = inet_sk(sk)->sport,
 326                                          .dport = ireq->rmt_port } } };
 327
 328         security_req_classify_flow(req, &fl);
 329         if (ip_route_output_flow(&rt, &fl, sk, 0)) {
 330                 IP_INC_STATS_BH(IPSTATS_MIB_OUTNOROUTES);
 331                 return NULL;
 332         }
 333         if (opt && opt->is_strictroute && rt->rt_dst != rt->rt_gateway) {
 334                 ip_rt_put(rt);
 335                 IP_INC_STATS_BH(IPSTATS_MIB_OUTNOROUTES);
 336                 return NULL;
 337         }
 338         return &rt->u.dst;
 339 }
 340
 341 EXPORT_SYMBOL_GPL(inet_csk_route_req);
 342
 343 static inline u32 inet_synq_hash(const __be32 raddr, const __be16 rport,
 344                                  const u32 rnd, const u32 synq_hsize)
 345 {
 346         return jhash_2words((__force u32)raddr, (__force u32)rport, rnd) & (synq_hsize - 1);
 347 }
 348
 349 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 350 #define AF_INET_FAMILY(fam) ((fam) == AF_INET)
 351 #else
 352 #define AF_INET_FAMILY(fam) 1
 353 #endif
 354
 355 struct request_sock *inet_csk_search_req(const struct sock *sk,
 356                                          struct request_sock ***prevp,
 357                                          const __be16 rport, const __be32 raddr,
 358                                          const __be32 laddr)
 359 {
 360         const struct inet_connection_sock *icsk = inet_csk(sk);
 361         struct listen_sock *lopt = icsk->icsk_accept_queue.listen_opt;
 362         struct request_sock *req, **prev;
 363
 364         for (prev = &lopt->syn_table[inet_synq_hash(raddr, rport, lopt->hash_rnd,
 365                                                     lopt->nr_table_entries)];
 366              (req = *prev) != NULL;
 367              prev = &req->dl_next) {
 368                 const struct inet_request_sock *ireq = inet_rsk(req);
 369
 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                         BUG_TRAP(!req->sk);
 375                         *prevp = prev;
 376                         break;
 377                 }
 378         }
 379
 380         return req;
 381 }
 382
 383 EXPORT_SYMBOL_GPL(inet_csk_search_req);
 384
 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
 393         reqsk_queue_hash_req(&icsk->icsk_accept_queue, h, req, timeout);
 394         inet_csk_reqsk_queue_added(sk, timeout);
 395 }
 396
 397 /* Only thing we need from tcp.h */
 398 extern int sysctl_tcp_synack_retries;
 399
 400 EXPORT_SYMBOL_GPL(inet_csk_reqsk_queue_hash_add);
 401
 402 void inet_csk_reqsk_queue_prune(struct sock *parent,
 403                                 const unsigned long interval,
 404                                 const unsigned long timeout,
 405                                 const unsigned long max_rto)
 406 {
 407         struct inet_connection_sock *icsk = inet_csk(parent);
 408         struct request_sock_queue *queue = &icsk->icsk_accept_queue;
 409         struct listen_sock *lopt = queue->listen_opt;
 410         int max_retries = icsk->icsk_syn_retries ? : sysctl_tcp_synack_retries;
 411         int thresh = max_retries;
 412         unsigned long now = jiffies;
 413         struct request_sock **reqp, *req;
 414         int i, budget;
 415
 416         if (lopt == NULL || lopt->qlen == 0)
 417                 return;
 418
 419         /* Normally all the openreqs are young and become mature
 420          * (i.e. converted to established socket) for first timeout.
 421          * If synack was not acknowledged for 3 seconds, it means
 422          * one of the following things: synack was lost, ack was lost,
 423          * rtt is high or nobody planned to ack (i.e. synflood).
 424          * When server is a bit loaded, queue is populated with old
 425          * open requests, reducing effective size of queue.
 426          * When server is well loaded, queue size reduces to zero
 427          * after several minutes of work. It is not synflood,
 428          * it is normal operation. The solution is pruning
 429          * too old entries overriding normal timeout, when
 430          * situation becomes dangerous.
 431          *
 432          * Essentially, we reserve half of room for young
 433          * embrions; and abort old ones without pity, if old
 434          * ones are about to clog our table.
 435          */
 436         if (lopt->qlen>>(lopt->max_qlen_log-1)) {
 437                 int young = (lopt->qlen_young<<1);
 438
 439                 while (thresh > 2) {
 440                         if (lopt->qlen < young)
 441                                 break;
 442                         thresh--;
 443                         young <<= 1;
 444                 }
 445         }
 446
 447         if (queue->rskq_defer_accept)
 448                 max_retries = queue->rskq_defer_accept;
 449
 450         budget = 2 * (lopt->nr_table_entries / (timeout / interval));
 451         i = lopt->clock_hand;
 452
 453         do {
 454                 reqp=&lopt->syn_table[i];
 455                 while ((req = *reqp) != NULL) {
 456                         if (time_after_eq(now, req->expires)) {
 457                                 if ((req->retrans < thresh ||
 458                                      (inet_rsk(req)->acked && req->retrans < max_retries))
 459                                     && !req->rsk_ops->rtx_syn_ack(parent, req, NULL)) {
 460                                         unsigned long timeo;
 461
 462                                         if (req->retrans++ == 0)
 463                                                 lopt->qlen_young--;
 464                                         timeo = min((timeout << req->retrans), max_rto);
 465                                         req->expires = now + timeo;
 466                                         reqp = &req->dl_next;
 467                                         continue;
 468                                 }
 469
 470                                 /* Drop this request */
 471                                 inet_csk_reqsk_queue_unlink(parent, req, reqp);
 472                                 reqsk_queue_removed(queue, req);
 473                                 reqsk_free(req);
 474                                 continue;
 475                         }
 476                         reqp = &req->dl_next;
 477                 }
 478
 479                 i = (i + 1) & (lopt->nr_table_entries - 1);
 480
 481         } while (--budget > 0);
 482
 483         lopt->clock_hand = i;
 484
 485         if (lopt->qlen)
 486                 inet_csk_reset_keepalive_timer(parent, interval);
 487 }
 488
 489 EXPORT_SYMBOL_GPL(inet_csk_reqsk_queue_prune);
 490
 491 struct sock *inet_csk_clone(struct sock *sk, const struct request_sock *req,
 492                             const gfp_t priority)
 493 {
 494         struct sock *newsk = sk_clone(sk, priority);
 495
 496         if (newsk != NULL) {
 497                 struct inet_connection_sock *newicsk = inet_csk(newsk);
 498
 499                 newsk->sk_state = TCP_SYN_RECV;
 500                 newicsk->icsk_bind_hash = NULL;
 501
 502                 inet_sk(newsk)->dport = inet_rsk(req)->rmt_port;
 503                 newsk->sk_write_space = sk_stream_write_space;
 504
 505                 newicsk->icsk_retransmits = 0;
 506                 newicsk->icsk_backoff     = 0;
 507                 newicsk->icsk_probes_out  = 0;
 508
 509                 /* Deinitialize accept_queue to trap illegal accesses. */
 510                 memset(&newicsk->icsk_accept_queue, 0, sizeof(newicsk->icsk_accept_queue));
 511
 512                 security_inet_csk_clone(newsk, req);
 513         }
 514         return newsk;
 515 }
 516
 517 EXPORT_SYMBOL_GPL(inet_csk_clone);
 518
 519 /*
 520  * At this point, there should be no process reference to this
 521  * socket, and thus no user references at all.  Therefore we
 522  * can assume the socket waitqueue is inactive and nobody will
 523  * try to jump onto it.
 524  */
 525 void inet_csk_destroy_sock(struct sock *sk)
 526 {
 527         BUG_TRAP(sk->sk_state == TCP_CLOSE);
 528         BUG_TRAP(sock_flag(sk, SOCK_DEAD));
 529
 530         /* It cannot be in hash table! */
 531         BUG_TRAP(sk_unhashed(sk));
 532
 533         /* If it has not 0 inet_sk(sk)->num, it must be bound */
 534         BUG_TRAP(!inet_sk(sk)->num || inet_csk(sk)->icsk_bind_hash);
 535
 536         sk->sk_prot->destroy(sk);
 537
 538         sk_stream_kill_queues(sk);
 539
 540         xfrm_sk_free_policy(sk);
 541
 542         sk_refcnt_debug_release(sk);
 543
 544         atomic_dec(sk->sk_prot->orphan_count);
 545         sock_put(sk);
 546 }
 547
 548 EXPORT_SYMBOL(inet_csk_destroy_sock);
 549
 550 int inet_csk_listen_start(struct sock *sk, const int nr_table_entries)
 551 {
 552         struct inet_sock *inet = inet_sk(sk);
 553         struct inet_connection_sock *icsk = inet_csk(sk);
 554         int rc = reqsk_queue_alloc(&icsk->icsk_accept_queue, nr_table_entries);
 555
 556         if (rc != 0)
 557                 return rc;
 558
 559         sk->sk_max_ack_backlog = 0;
 560         sk->sk_ack_backlog = 0;
 561         inet_csk_delack_init(sk);
 562
 563         /* There is race window here: we announce ourselves listening,
 564          * but this transition is still not validated by get_port().
 565          * It is OK, because this socket enters to hash table only
 566          * after validation is complete.
 567          */
 568         sk->sk_state = TCP_LISTEN;
 569         if (!sk->sk_prot->get_port(sk, inet->num)) {
 570                 inet->sport = htons(inet->num);
 571
 572                 sk_dst_reset(sk);
 573                 sk->sk_prot->hash(sk);
 574
 575                 return 0;
 576         }
 577
 578         sk->sk_state = TCP_CLOSE;
 579         __reqsk_queue_destroy(&icsk->icsk_accept_queue);
 580         return -EADDRINUSE;
 581 }
 582
 583 EXPORT_SYMBOL_GPL(inet_csk_listen_start);
 584
 585 /*
 586  *      This routine closes sockets which have been at least partially
 587  *      opened, but not yet accepted.
 588  */
 589 void inet_csk_listen_stop(struct sock *sk)
 590 {
 591         struct inet_connection_sock *icsk = inet_csk(sk);
 592         struct request_sock *acc_req;
 593         struct request_sock *req;
 594
 595         inet_csk_delete_keepalive_timer(sk);
 596
 597         /* make all the listen_opt local to us */
 598         acc_req = reqsk_queue_yank_acceptq(&icsk->icsk_accept_queue);
 599
 600         /* Following specs, it would be better either to send FIN
 601          * (and enter FIN-WAIT-1, it is normal close)
 602          * or to send active reset (abort).
 603          * Certainly, it is pretty dangerous while synflood, but it is
 604          * bad justification for our negligence 8)
 605          * To be honest, we are not able to make either
 606          * of the variants now.                 --ANK
 607          */
 608         reqsk_queue_destroy(&icsk->icsk_accept_queue);
 609
 610         while ((req = acc_req) != NULL) {
 611                 struct sock *child = req->sk;
 612
 613                 acc_req = req->dl_next;
 614
 615                 local_bh_disable();
 616                 bh_lock_sock(child);
 617                 BUG_TRAP(!sock_owned_by_user(child));
 618                 sock_hold(child);
 619
 620                 sk->sk_prot->disconnect(child, O_NONBLOCK);
 621
 622                 sock_orphan(child);
 623
 624                 atomic_inc(sk->sk_prot->orphan_count);
 625
 626                 inet_csk_destroy_sock(child);
 627
 628                 bh_unlock_sock(child);
 629                 local_bh_enable();
 630                 sock_put(child);
 631
 632                 sk_acceptq_removed(sk);
 633                 __reqsk_free(req);
 634         }
 635         BUG_TRAP(!sk->sk_ack_backlog);
 636 }
 637
 638 EXPORT_SYMBOL_GPL(inet_csk_listen_stop);
 639
 640 void inet_csk_addr2sockaddr(struct sock *sk, struct sockaddr *uaddr)
 641 {
 642         struct sockaddr_in *sin = (struct sockaddr_in *)uaddr;
 643         const struct inet_sock *inet = inet_sk(sk);
 644
 645         sin->sin_family         = AF_INET;
 646         sin->sin_addr.s_addr    = inet->daddr;
 647         sin->sin_port           = inet->dport;
 648 }
 649
 650 EXPORT_SYMBOL_GPL(inet_csk_addr2sockaddr);
 651
 652 int inet_csk_ctl_sock_create(struct socket **sock, unsigned short family,
 653                              unsigned short type, unsigned char protocol)
 654 {
 655         int rc = sock_create_kern(family, type, protocol, sock);
 656
 657         if (rc == 0) {
 658                 (*sock)->sk->sk_allocation = GFP_ATOMIC;
 659                 inet_sk((*sock)->sk)->uc_ttl = -1;
 660                 /*
 661                  * Unhash it so that IP input processing does not even see it,
 662                  * we do not wish this socket to see incoming packets.
 663                  */
 664                 (*sock)->sk->sk_prot->unhash((*sock)->sk);
 665         }
 666         return rc;
 667 }
 668
 669 EXPORT_SYMBOL_GPL(inet_csk_ctl_sock_create);
 670
 671 #ifdef CONFIG_COMPAT
 672 int inet_csk_compat_getsockopt(struct sock *sk, int level, int optname,
 673                                char __user *optval, int __user *optlen)
 674 {
 675         const struct inet_connection_sock *icsk = inet_csk(sk);
 676
 677         if (icsk->icsk_af_ops->compat_getsockopt != NULL)
 678                 return icsk->icsk_af_ops->compat_getsockopt(sk, level, optname,
 679                                                             optval, optlen);
 680         return icsk->icsk_af_ops->getsockopt(sk, level, optname,
 681                                              optval, optlen);
 682 }
 683
 684 EXPORT_SYMBOL_GPL(inet_csk_compat_getsockopt);
 685
 686 int inet_csk_compat_setsockopt(struct sock *sk, int level, int optname,
 687                                char __user *optval, int optlen)
 688 {
 689         const struct inet_connection_sock *icsk = inet_csk(sk);
 690
 691         if (icsk->icsk_af_ops->compat_setsockopt != NULL)
 692                 return icsk->icsk_af_ops->compat_setsockopt(sk, level, optname,
 693                                                             optval, optlen);
 694         return icsk->icsk_af_ops->setsockopt(sk, level, optname,
 695                                              optval, optlen);
 696 }
 697
 698 EXPORT_SYMBOL_GPL(inet_csk_compat_setsockopt);
 699 #endif