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 DEFINE_SEQLOCK(sysctl_port_range_lock);
  37
  38 void inet_get_local_port_range(int *low, int *high)
  39 {
  40         unsigned seq;
  41         do {
  42                 seq = read_seqbegin(&sysctl_port_range_lock);
  43
  44                 *low = sysctl_local_port_range[0];
  45                 *high = sysctl_local_port_range[1];
  46         } while (read_seqretry(&sysctl_port_range_lock, seq));
  47 }
  48 EXPORT_SYMBOL(inet_get_local_port_range);
  49
  50 int inet_csk_bind_conflict(const struct sock *sk,
  51                            const struct inet_bind_bucket *tb)
  52 {
  53         const __be32 sk_rcv_saddr = inet_rcv_saddr(sk);
  54         struct sock *sk2;
  55         struct hlist_node *node;
  56         int reuse = sk->sk_reuse;
  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
  76 EXPORT_SYMBOL_GPL(inet_csk_bind_conflict);
  77
  78 /* Obtain a reference to a local port for the given sock,
  79  * if snum is zero it means select any available local port.
  80  */
  81 int inet_csk_get_port(struct inet_hashinfo *hashinfo,
  82                       struct sock *sk, unsigned short snum,
  83                       int (*bind_conflict)(const struct sock *sk,
  84                                            const struct inet_bind_bucket *tb))
  85 {
  86         struct inet_bind_hashbucket *head;
  87         struct hlist_node *node;
  88         struct inet_bind_bucket *tb;
  89         int ret;
  90         struct net *net = sk->sk_net;
  91
  92         local_bh_disable();
  93         if (!snum) {
  94                 int remaining, rover, low, high;
  95
  96                 inet_get_local_port_range(&low, &high);
  97                 remaining = (high - low) + 1;
  98                 rover = net_random() % remaining + low;
  99
 100                 do {
 101                         head = &hashinfo->bhash[inet_bhashfn(rover, hashinfo->bhash_size)];
 102                         spin_lock(&head->lock);
 103                         inet_bind_bucket_for_each(tb, node, &head->chain)
 104                                 if (tb->ib_net == net && tb->port == rover)
 105                                         goto next;
 106                         break;
 107                 next:
 108                         spin_unlock(&head->lock);
 109                         if (++rover > high)
 110                                 rover = low;
 111                 } while (--remaining > 0);
 112
 113                 /* Exhausted local port range during search?  It is not
 114                  * possible for us to be holding one of the bind hash
 115                  * locks if this test triggers, because if 'remaining'
 116                  * drops to zero, we broke out of the do/while loop at
 117                  * the top level, not from the 'break;' statement.
 118                  */
 119                 ret = 1;
 120                 if (remaining <= 0)
 121                         goto fail;
 122
 123                 /* OK, here is the one we will use.  HEAD is
 124                  * non-NULL and we hold it's mutex.
 125                  */
 126                 snum = rover;
 127         } else {
 128                 head = &hashinfo->bhash[inet_bhashfn(snum, hashinfo->bhash_size)];
 129                 spin_lock(&head->lock);
 130                 inet_bind_bucket_for_each(tb, node, &head->chain)
 131                         if (tb->ib_net == net && tb->port == snum)
 132                                 goto tb_found;
 133         }
 134         tb = NULL;
 135         goto tb_not_found;
 136 tb_found:
 137         if (!hlist_empty(&tb->owners)) {
 138                 if (sk->sk_reuse > 1)
 139                         goto success;
 140                 if (tb->fastreuse > 0 &&
 141                     sk->sk_reuse && sk->sk_state != TCP_LISTEN) {
 142                         goto success;
 143                 } else {
 144                         ret = 1;
 145                         if (bind_conflict(sk, tb))
 146                                 goto fail_unlock;
 147                 }
 148         }
 149 tb_not_found:
 150         ret = 1;
 151         if (!tb && (tb = inet_bind_bucket_create(hashinfo->bind_bucket_cachep,
 152                                         net, head, snum)) == NULL)
 153                 goto fail_unlock;
 154         if (hlist_empty(&tb->owners)) {
 155                 if (sk->sk_reuse && sk->sk_state != TCP_LISTEN)
 156                         tb->fastreuse = 1;
 157                 else
 158                         tb->fastreuse = 0;
 159         } else if (tb->fastreuse &&
 160                    (!sk->sk_reuse || sk->sk_state == TCP_LISTEN))
 161                 tb->fastreuse = 0;
 162 success:
 163         if (!inet_csk(sk)->icsk_bind_hash)
 164                 inet_bind_hash(sk, tb, snum);
 165         BUG_TRAP(inet_csk(sk)->icsk_bind_hash == tb);
 166         ret = 0;
 167
 168 fail_unlock:
 169         spin_unlock(&head->lock);
 170 fail:
 171         local_bh_enable();
 172         return ret;
 173 }
 174
 175 EXPORT_SYMBOL_GPL(inet_csk_get_port);
 176
 177 /*
 178  * Wait for an incoming connection, avoid race conditions. This must be called
 179  * with the socket locked.
 180  */
 181 static int inet_csk_wait_for_connect(struct sock *sk, long timeo)
 182 {
 183         struct inet_connection_sock *icsk = inet_csk(sk);
 184         DEFINE_WAIT(wait);
 185         int err;
 186
 187         /*
 188          * True wake-one mechanism for incoming connections: only
 189          * one process gets woken up, not the 'whole herd'.
 190          * Since we do not 'race & poll' for established sockets
 191          * anymore, the common case will execute the loop only once.
 192          *
 193          * Subtle issue: "add_wait_queue_exclusive()" will be added
 194          * after any current non-exclusive waiters, and we know that
 195          * it will always _stay_ after any new non-exclusive waiters
 196          * because all non-exclusive waiters are added at the
 197          * beginning of the wait-queue. As such, it's ok to "drop"
 198          * our exclusiveness temporarily when we get woken up without
 199          * having to remove and re-insert us on the wait queue.
 200          */
 201         for (;;) {
 202                 prepare_to_wait_exclusive(sk->sk_sleep, &wait,
 203                                           TASK_INTERRUPTIBLE);
 204                 release_sock(sk);
 205                 if (reqsk_queue_empty(&icsk->icsk_accept_queue))
 206                         timeo = schedule_timeout(timeo);
 207                 lock_sock(sk);
 208                 err = 0;
 209                 if (!reqsk_queue_empty(&icsk->icsk_accept_queue))
 210                         break;
 211                 err = -EINVAL;
 212                 if (sk->sk_state != TCP_LISTEN)
 213                         break;
 214                 err = sock_intr_errno(timeo);
 215                 if (signal_pending(current))
 216                         break;
 217                 err = -EAGAIN;
 218                 if (!timeo)
 219                         break;
 220         }
 221         finish_wait(sk->sk_sleep, &wait);
 222         return err;
 223 }
 224
 225 /*
 226  * This will accept the next outstanding connection.
 227  */
 228 struct sock *inet_csk_accept(struct sock *sk, int flags, int *err)
 229 {
 230         struct inet_connection_sock *icsk = inet_csk(sk);
 231         struct sock *newsk;
 232         int error;
 233
 234         lock_sock(sk);
 235
 236         /* We need to make sure that this socket is listening,
 237          * and that it has something pending.
 238          */
 239         error = -EINVAL;
 240         if (sk->sk_state != TCP_LISTEN)
 241                 goto out_err;
 242
 243         /* Find already established connection */
 244         if (reqsk_queue_empty(&icsk->icsk_accept_queue)) {
 245                 long timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
 246
 247                 /* If this is a non blocking socket don't sleep */
 248                 error = -EAGAIN;
 249                 if (!timeo)
 250                         goto out_err;
 251
 252                 error = inet_csk_wait_for_connect(sk, timeo);
 253                 if (error)
 254                         goto out_err;
 255         }
 256
 257         newsk = reqsk_queue_get_child(&icsk->icsk_accept_queue, sk);
 258         BUG_TRAP(newsk->sk_state != TCP_SYN_RECV);
 259 out:
 260         release_sock(sk);
 261         return newsk;
 262 out_err:
 263         newsk = NULL;
 264         *err = error;
 265         goto out;
 266 }
 267
 268 EXPORT_SYMBOL(inet_csk_accept);
 269
 270 /*
 271  * Using different timers for retransmit, delayed acks and probes
 272  * We may wish use just one timer maintaining a list of expire jiffies
 273  * to optimize.
 274  */
 275 void inet_csk_init_xmit_timers(struct sock *sk,
 276                                void (*retransmit_handler)(unsigned long),
 277                                void (*delack_handler)(unsigned long),
 278                                void (*keepalive_handler)(unsigned long))
 279 {
 280         struct inet_connection_sock *icsk = inet_csk(sk);
 281
 282         setup_timer(&icsk->icsk_retransmit_timer, retransmit_handler,
 283                         (unsigned long)sk);
 284         setup_timer(&icsk->icsk_delack_timer, delack_handler,
 285                         (unsigned long)sk);
 286         setup_timer(&sk->sk_timer, keepalive_handler, (unsigned long)sk);
 287         icsk->icsk_pending = icsk->icsk_ack.pending = 0;
 288 }
 289
 290 EXPORT_SYMBOL(inet_csk_init_xmit_timers);
 291
 292 void inet_csk_clear_xmit_timers(struct sock *sk)
 293 {
 294         struct inet_connection_sock *icsk = inet_csk(sk);
 295
 296         icsk->icsk_pending = icsk->icsk_ack.pending = icsk->icsk_ack.blocked = 0;
 297
 298         sk_stop_timer(sk, &icsk->icsk_retransmit_timer);
 299         sk_stop_timer(sk, &icsk->icsk_delack_timer);
 300         sk_stop_timer(sk, &sk->sk_timer);
 301 }
 302
 303 EXPORT_SYMBOL(inet_csk_clear_xmit_timers);
 304
 305 void inet_csk_delete_keepalive_timer(struct sock *sk)
 306 {
 307         sk_stop_timer(sk, &sk->sk_timer);
 308 }
 309
 310 EXPORT_SYMBOL(inet_csk_delete_keepalive_timer);
 311
 312 void inet_csk_reset_keepalive_timer(struct sock *sk, unsigned long len)
 313 {
 314         sk_reset_timer(sk, &sk->sk_timer, jiffies + len);
 315 }
 316
 317 EXPORT_SYMBOL(inet_csk_reset_keepalive_timer);
 318
 319 struct dst_entry* inet_csk_route_req(struct sock *sk,
 320                                      const struct request_sock *req)
 321 {
 322         struct rtable *rt;
 323         const struct inet_request_sock *ireq = inet_rsk(req);
 324         struct ip_options *opt = inet_rsk(req)->opt;
 325         struct flowi fl = { .oif = sk->sk_bound_dev_if,
 326                             .nl_u = { .ip4_u =
 327                                       { .daddr = ((opt && opt->srr) ?
 328                                                   opt->faddr :
 329                                                   ireq->rmt_addr),
 330                                         .saddr = ireq->loc_addr,
 331                                         .tos = RT_CONN_FLAGS(sk) } },
 332                             .proto = sk->sk_protocol,
 333                             .uli_u = { .ports =
 334                                        { .sport = inet_sk(sk)->sport,
 335                                          .dport = ireq->rmt_port } } };
 336
 337         security_req_classify_flow(req, &fl);
 338         if (ip_route_output_flow(&init_net, &rt, &fl, sk, 0)) {
 339                 IP_INC_STATS_BH(IPSTATS_MIB_OUTNOROUTES);
 340                 return NULL;
 341         }
 342         if (opt && opt->is_strictroute && rt->rt_dst != rt->rt_gateway) {
 343                 ip_rt_put(rt);
 344                 IP_INC_STATS_BH(IPSTATS_MIB_OUTNOROUTES);
 345                 return NULL;
 346         }
 347         return &rt->u.dst;
 348 }
 349
 350 EXPORT_SYMBOL_GPL(inet_csk_route_req);
 351
 352 static inline u32 inet_synq_hash(const __be32 raddr, const __be16 rport,
 353                                  const u32 rnd, const u32 synq_hsize)
 354 {
 355         return jhash_2words((__force u32)raddr, (__force u32)rport, rnd) & (synq_hsize - 1);
 356 }
 357
 358 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 359 #define AF_INET_FAMILY(fam) ((fam) == AF_INET)
 360 #else
 361 #define AF_INET_FAMILY(fam) 1
 362 #endif
 363
 364 struct request_sock *inet_csk_search_req(const struct sock *sk,
 365                                          struct request_sock ***prevp,
 366                                          const __be16 rport, const __be32 raddr,
 367                                          const __be32 laddr)
 368 {
 369         const struct inet_connection_sock *icsk = inet_csk(sk);
 370         struct listen_sock *lopt = icsk->icsk_accept_queue.listen_opt;
 371         struct request_sock *req, **prev;
 372
 373         for (prev = &lopt->syn_table[inet_synq_hash(raddr, rport, lopt->hash_rnd,
 374                                                     lopt->nr_table_entries)];
 375              (req = *prev) != NULL;
 376              prev = &req->dl_next) {
 377                 const struct inet_request_sock *ireq = inet_rsk(req);
 378
 379                 if (ireq->rmt_port == rport &&
 380                     ireq->rmt_addr == raddr &&
 381                     ireq->loc_addr == laddr &&
 382                     AF_INET_FAMILY(req->rsk_ops->family)) {
 383                         BUG_TRAP(!req->sk);
 384                         *prevp = prev;
 385                         break;
 386                 }
 387         }
 388
 389         return req;
 390 }
 391
 392 EXPORT_SYMBOL_GPL(inet_csk_search_req);
 393
 394 void inet_csk_reqsk_queue_hash_add(struct sock *sk, struct request_sock *req,
 395                                    unsigned long timeout)
 396 {
 397         struct inet_connection_sock *icsk = inet_csk(sk);
 398         struct listen_sock *lopt = icsk->icsk_accept_queue.listen_opt;
 399         const u32 h = inet_synq_hash(inet_rsk(req)->rmt_addr, inet_rsk(req)->rmt_port,
 400                                      lopt->hash_rnd, lopt->nr_table_entries);
 401
 402         reqsk_queue_hash_req(&icsk->icsk_accept_queue, h, req, timeout);
 403         inet_csk_reqsk_queue_added(sk, timeout);
 404 }
 405
 406 /* Only thing we need from tcp.h */
 407 extern int sysctl_tcp_synack_retries;
 408
 409 EXPORT_SYMBOL_GPL(inet_csk_reqsk_queue_hash_add);
 410
 411 void inet_csk_reqsk_queue_prune(struct sock *parent,
 412                                 const unsigned long interval,
 413                                 const unsigned long timeout,
 414                                 const unsigned long max_rto)
 415 {
 416         struct inet_connection_sock *icsk = inet_csk(parent);
 417         struct request_sock_queue *queue = &icsk->icsk_accept_queue;
 418         struct listen_sock *lopt = queue->listen_opt;
 419         int max_retries = icsk->icsk_syn_retries ? : sysctl_tcp_synack_retries;
 420         int thresh = max_retries;
 421         unsigned long now = jiffies;
 422         struct request_sock **reqp, *req;
 423         int i, budget;
 424
 425         if (lopt == NULL || lopt->qlen == 0)
 426                 return;
 427
 428         /* Normally all the openreqs are young and become mature
 429          * (i.e. converted to established socket) for first timeout.
 430          * If synack was not acknowledged for 3 seconds, it means
 431          * one of the following things: synack was lost, ack was lost,
 432          * rtt is high or nobody planned to ack (i.e. synflood).
 433          * When server is a bit loaded, queue is populated with old
 434          * open requests, reducing effective size of queue.
 435          * When server is well loaded, queue size reduces to zero
 436          * after several minutes of work. It is not synflood,
 437          * it is normal operation. The solution is pruning
 438          * too old entries overriding normal timeout, when
 439          * situation becomes dangerous.
 440          *
 441          * Essentially, we reserve half of room for young
 442          * embrions; and abort old ones without pity, if old
 443          * ones are about to clog our table.
 444          */
 445         if (lopt->qlen>>(lopt->max_qlen_log-1)) {
 446                 int young = (lopt->qlen_young<<1);
 447
 448                 while (thresh > 2) {
 449                         if (lopt->qlen < young)
 450                                 break;
 451                         thresh--;
 452                         young <<= 1;
 453                 }
 454         }
 455
 456         if (queue->rskq_defer_accept)
 457                 max_retries = queue->rskq_defer_accept;
 458
 459         budget = 2 * (lopt->nr_table_entries / (timeout / interval));
 460         i = lopt->clock_hand;
 461
 462         do {
 463                 reqp=&lopt->syn_table[i];
 464                 while ((req = *reqp) != NULL) {
 465                         if (time_after_eq(now, req->expires)) {
 466                                 if ((req->retrans < thresh ||
 467                                      (inet_rsk(req)->acked && req->retrans < max_retries))
 468                                     && !req->rsk_ops->rtx_syn_ack(parent, req, NULL)) {
 469                                         unsigned long timeo;
 470
 471                                         if (req->retrans++ == 0)
 472                                                 lopt->qlen_young--;
 473                                         timeo = min((timeout << req->retrans), max_rto);
 474                                         req->expires = now + timeo;
 475                                         reqp = &req->dl_next;
 476                                         continue;
 477                                 }
 478
 479                                 /* Drop this request */
 480                                 inet_csk_reqsk_queue_unlink(parent, req, reqp);
 481                                 reqsk_queue_removed(queue, req);
 482                                 reqsk_free(req);
 483                                 continue;
 484                         }
 485                         reqp = &req->dl_next;
 486                 }
 487
 488                 i = (i + 1) & (lopt->nr_table_entries - 1);
 489
 490         } while (--budget > 0);
 491
 492         lopt->clock_hand = i;
 493
 494         if (lopt->qlen)
 495                 inet_csk_reset_keepalive_timer(parent, interval);
 496 }
 497
 498 EXPORT_SYMBOL_GPL(inet_csk_reqsk_queue_prune);
 499
 500 struct sock *inet_csk_clone(struct sock *sk, const struct request_sock *req,
 501                             const gfp_t priority)
 502 {
 503         struct sock *newsk = sk_clone(sk, priority);
 504
 505         if (newsk != NULL) {
 506                 struct inet_connection_sock *newicsk = inet_csk(newsk);
 507
 508                 newsk->sk_state = TCP_SYN_RECV;
 509                 newicsk->icsk_bind_hash = NULL;
 510
 511                 inet_sk(newsk)->dport = inet_rsk(req)->rmt_port;
 512                 newsk->sk_write_space = sk_stream_write_space;
 513
 514                 newicsk->icsk_retransmits = 0;
 515                 newicsk->icsk_backoff     = 0;
 516                 newicsk->icsk_probes_out  = 0;
 517
 518                 /* Deinitialize accept_queue to trap illegal accesses. */
 519                 memset(&newicsk->icsk_accept_queue, 0, sizeof(newicsk->icsk_accept_queue));
 520
 521                 security_inet_csk_clone(newsk, req);
 522         }
 523         return newsk;
 524 }
 525
 526 EXPORT_SYMBOL_GPL(inet_csk_clone);
 527
 528 /*
 529  * At this point, there should be no process reference to this
 530  * socket, and thus no user references at all.  Therefore we
 531  * can assume the socket waitqueue is inactive and nobody will
 532  * try to jump onto it.
 533  */
 534 void inet_csk_destroy_sock(struct sock *sk)
 535 {
 536         BUG_TRAP(sk->sk_state == TCP_CLOSE);
 537         BUG_TRAP(sock_flag(sk, SOCK_DEAD));
 538
 539         /* It cannot be in hash table! */
 540         BUG_TRAP(sk_unhashed(sk));
 541
 542         /* If it has not 0 inet_sk(sk)->num, it must be bound */
 543         BUG_TRAP(!inet_sk(sk)->num || inet_csk(sk)->icsk_bind_hash);
 544
 545         sk->sk_prot->destroy(sk);
 546
 547         sk_stream_kill_queues(sk);
 548
 549         xfrm_sk_free_policy(sk);
 550
 551         sk_refcnt_debug_release(sk);
 552
 553         atomic_dec(sk->sk_prot->orphan_count);
 554         sock_put(sk);
 555 }
 556
 557 EXPORT_SYMBOL(inet_csk_destroy_sock);
 558
 559 int inet_csk_listen_start(struct sock *sk, const int nr_table_entries)
 560 {
 561         struct inet_sock *inet = inet_sk(sk);
 562         struct inet_connection_sock *icsk = inet_csk(sk);
 563         int rc = reqsk_queue_alloc(&icsk->icsk_accept_queue, nr_table_entries);
 564
 565         if (rc != 0)
 566                 return rc;
 567
 568         sk->sk_max_ack_backlog = 0;
 569         sk->sk_ack_backlog = 0;
 570         inet_csk_delack_init(sk);
 571
 572         /* There is race window here: we announce ourselves listening,
 573          * but this transition is still not validated by get_port().
 574          * It is OK, because this socket enters to hash table only
 575          * after validation is complete.
 576          */
 577         sk->sk_state = TCP_LISTEN;
 578         if (!sk->sk_prot->get_port(sk, inet->num)) {
 579                 inet->sport = htons(inet->num);
 580
 581                 sk_dst_reset(sk);
 582                 sk->sk_prot->hash(sk);
 583
 584                 return 0;
 585         }
 586
 587         sk->sk_state = TCP_CLOSE;
 588         __reqsk_queue_destroy(&icsk->icsk_accept_queue);
 589         return -EADDRINUSE;
 590 }
 591
 592 EXPORT_SYMBOL_GPL(inet_csk_listen_start);
 593
 594 /*
 595  *      This routine closes sockets which have been at least partially
 596  *      opened, but not yet accepted.
 597  */
 598 void inet_csk_listen_stop(struct sock *sk)
 599 {
 600         struct inet_connection_sock *icsk = inet_csk(sk);
 601         struct request_sock *acc_req;
 602         struct request_sock *req;
 603
 604         inet_csk_delete_keepalive_timer(sk);
 605
 606         /* make all the listen_opt local to us */
 607         acc_req = reqsk_queue_yank_acceptq(&icsk->icsk_accept_queue);
 608
 609         /* Following specs, it would be better either to send FIN
 610          * (and enter FIN-WAIT-1, it is normal close)
 611          * or to send active reset (abort).
 612          * Certainly, it is pretty dangerous while synflood, but it is
 613          * bad justification for our negligence 8)
 614          * To be honest, we are not able to make either
 615          * of the variants now.                 --ANK
 616          */
 617         reqsk_queue_destroy(&icsk->icsk_accept_queue);
 618
 619         while ((req = acc_req) != NULL) {
 620                 struct sock *child = req->sk;
 621
 622                 acc_req = req->dl_next;
 623
 624                 local_bh_disable();
 625                 bh_lock_sock(child);
 626                 BUG_TRAP(!sock_owned_by_user(child));
 627                 sock_hold(child);
 628
 629                 sk->sk_prot->disconnect(child, O_NONBLOCK);
 630
 631                 sock_orphan(child);
 632
 633                 atomic_inc(sk->sk_prot->orphan_count);
 634
 635                 inet_csk_destroy_sock(child);
 636
 637                 bh_unlock_sock(child);
 638                 local_bh_enable();
 639                 sock_put(child);
 640
 641                 sk_acceptq_removed(sk);
 642                 __reqsk_free(req);
 643         }
 644         BUG_TRAP(!sk->sk_ack_backlog);
 645 }
 646
 647 EXPORT_SYMBOL_GPL(inet_csk_listen_stop);
 648
 649 void inet_csk_addr2sockaddr(struct sock *sk, struct sockaddr *uaddr)
 650 {
 651         struct sockaddr_in *sin = (struct sockaddr_in *)uaddr;
 652         const struct inet_sock *inet = inet_sk(sk);
 653
 654         sin->sin_family         = AF_INET;
 655         sin->sin_addr.s_addr    = inet->daddr;
 656         sin->sin_port           = inet->dport;
 657 }
 658
 659 EXPORT_SYMBOL_GPL(inet_csk_addr2sockaddr);
 660
 661 int inet_csk_ctl_sock_create(struct socket **sock, unsigned short family,
 662                              unsigned short type, unsigned char protocol)
 663 {
 664         int rc = sock_create_kern(family, type, protocol, sock);
 665
 666         if (rc == 0) {
 667                 (*sock)->sk->sk_allocation = GFP_ATOMIC;
 668                 inet_sk((*sock)->sk)->uc_ttl = -1;
 669                 /*
 670                  * Unhash it so that IP input processing does not even see it,
 671                  * we do not wish this socket to see incoming packets.
 672                  */
 673                 (*sock)->sk->sk_prot->unhash((*sock)->sk);
 674         }
 675         return rc;
 676 }
 677
 678 EXPORT_SYMBOL_GPL(inet_csk_ctl_sock_create);
 679
 680 #ifdef CONFIG_COMPAT
 681 int inet_csk_compat_getsockopt(struct sock *sk, int level, int optname,
 682                                char __user *optval, int __user *optlen)
 683 {
 684         const struct inet_connection_sock *icsk = inet_csk(sk);
 685
 686         if (icsk->icsk_af_ops->compat_getsockopt != NULL)
 687                 return icsk->icsk_af_ops->compat_getsockopt(sk, level, optname,
 688                                                             optval, optlen);
 689         return icsk->icsk_af_ops->getsockopt(sk, level, optname,
 690                                              optval, optlen);
 691 }
 692
 693 EXPORT_SYMBOL_GPL(inet_csk_compat_getsockopt);
 694
 695 int inet_csk_compat_setsockopt(struct sock *sk, int level, int optname,
 696                                char __user *optval, int optlen)
 697 {
 698         const struct inet_connection_sock *icsk = inet_csk(sk);
 699
 700         if (icsk->icsk_af_ops->compat_setsockopt != NULL)
 701                 return icsk->icsk_af_ops->compat_setsockopt(sk, level, optname,
 702                                                             optval, optlen);
 703         return icsk->icsk_af_ops->setsockopt(sk, level, optname,
 704                                              optval, optlen);
 705 }
 706
 707 EXPORT_SYMBOL_GPL(inet_csk_compat_setsockopt);
 708 #endif