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CommitLineData
3f421baa
ACM
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
3f421baa
ACM
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>
a019d6fe 25#include <net/xfrm.h>
3f421baa
ACM
26
27#ifdef INET_CSK_DEBUG
28const char inet_csk_timer_bug_msg[] = "inet_csk BUG: unknown timer value\n";
29EXPORT_SYMBOL(inet_csk_timer_bug_msg);
30#endif
31
32/*
3c689b73 33 * This struct holds the first and last local port number.
3f421baa 34 */
3c689b73
ED
35struct local_ports sysctl_local_ports __read_mostly = {
36 .lock = SEQLOCK_UNLOCKED,
37 .range = { 32768, 61000 },
38};
227b60f5 39
e3826f1e
AW
40unsigned long *sysctl_local_reserved_ports;
41EXPORT_SYMBOL(sysctl_local_reserved_ports);
42
227b60f5
SH
43void inet_get_local_port_range(int *low, int *high)
44{
45 unsigned seq;
46 do {
3c689b73 47 seq = read_seqbegin(&sysctl_local_ports.lock);
227b60f5 48
3c689b73
ED
49 *low = sysctl_local_ports.range[0];
50 *high = sysctl_local_ports.range[1];
51 } while (read_seqretry(&sysctl_local_ports.lock, seq));
227b60f5
SH
52}
53EXPORT_SYMBOL(inet_get_local_port_range);
3f421baa 54
971af18b
ACM
55int inet_csk_bind_conflict(const struct sock *sk,
56 const struct inet_bind_bucket *tb)
3f421baa 57{
3f421baa
ACM
58 struct sock *sk2;
59 struct hlist_node *node;
60 int reuse = sk->sk_reuse;
61
7477fd2e
PE
62 /*
63 * Unlike other sk lookup places we do not check
64 * for sk_net here, since _all_ the socks listed
65 * in tb->owners list belong to the same net - the
66 * one this bucket belongs to.
67 */
68
3f421baa
ACM
69 sk_for_each_bound(sk2, node, &tb->owners) {
70 if (sk != sk2 &&
71 !inet_v6_ipv6only(sk2) &&
72 (!sk->sk_bound_dev_if ||
73 !sk2->sk_bound_dev_if ||
74 sk->sk_bound_dev_if == sk2->sk_bound_dev_if)) {
75 if (!reuse || !sk2->sk_reuse ||
3e8c806a 76 sk2->sk_state == TCP_LISTEN) {
68835aba
ED
77 const __be32 sk2_rcv_saddr = sk_rcv_saddr(sk2);
78 if (!sk2_rcv_saddr || !sk_rcv_saddr(sk) ||
79 sk2_rcv_saddr == sk_rcv_saddr(sk))
3f421baa 80 break;
8d238b25 81 }
3f421baa
ACM
82 }
83 }
84 return node != NULL;
85}
971af18b
ACM
86EXPORT_SYMBOL_GPL(inet_csk_bind_conflict);
87
3f421baa
ACM
88/* Obtain a reference to a local port for the given sock,
89 * if snum is zero it means select any available local port.
90 */
ab1e0a13 91int inet_csk_get_port(struct sock *sk, unsigned short snum)
3f421baa 92{
39d8cda7 93 struct inet_hashinfo *hashinfo = sk->sk_prot->h.hashinfo;
3f421baa
ACM
94 struct inet_bind_hashbucket *head;
95 struct hlist_node *node;
96 struct inet_bind_bucket *tb;
a9d8f911 97 int ret, attempts = 5;
3b1e0a65 98 struct net *net = sock_net(sk);
a9d8f911 99 int smallest_size = -1, smallest_rover;
3f421baa
ACM
100
101 local_bh_disable();
102 if (!snum) {
227b60f5
SH
103 int remaining, rover, low, high;
104
a9d8f911 105again:
227b60f5 106 inet_get_local_port_range(&low, &high);
a25de534 107 remaining = (high - low) + 1;
a9d8f911 108 smallest_rover = rover = net_random() % remaining + low;
3f421baa 109
a9d8f911 110 smallest_size = -1;
3f421baa 111 do {
e3826f1e
AW
112 if (inet_is_reserved_local_port(rover))
113 goto next_nolock;
7f635ab7
PE
114 head = &hashinfo->bhash[inet_bhashfn(net, rover,
115 hashinfo->bhash_size)];
3f421baa
ACM
116 spin_lock(&head->lock);
117 inet_bind_bucket_for_each(tb, node, &head->chain)
09ad9bc7 118 if (net_eq(ib_net(tb), net) && tb->port == rover) {
a9d8f911
EP
119 if (tb->fastreuse > 0 &&
120 sk->sk_reuse &&
121 sk->sk_state != TCP_LISTEN &&
122 (tb->num_owners < smallest_size || smallest_size == -1)) {
123 smallest_size = tb->num_owners;
124 smallest_rover = rover;
3e8c806a 125 if (atomic_read(&hashinfo->bsockets) > (high - low) + 1) {
8d238b25
DM
126 spin_unlock(&head->lock);
127 snum = smallest_rover;
128 goto have_snum;
a9d8f911
EP
129 }
130 }
3f421baa 131 goto next;
a9d8f911 132 }
3f421baa
ACM
133 break;
134 next:
135 spin_unlock(&head->lock);
e3826f1e 136 next_nolock:
6df71634
SH
137 if (++rover > high)
138 rover = low;
3f421baa 139 } while (--remaining > 0);
3f421baa
ACM
140
141 /* Exhausted local port range during search? It is not
142 * possible for us to be holding one of the bind hash
143 * locks if this test triggers, because if 'remaining'
144 * drops to zero, we broke out of the do/while loop at
145 * the top level, not from the 'break;' statement.
146 */
147 ret = 1;
a9d8f911
EP
148 if (remaining <= 0) {
149 if (smallest_size != -1) {
150 snum = smallest_rover;
151 goto have_snum;
152 }
3f421baa 153 goto fail;
a9d8f911 154 }
3f421baa
ACM
155 /* OK, here is the one we will use. HEAD is
156 * non-NULL and we hold it's mutex.
157 */
158 snum = rover;
159 } else {
a9d8f911 160have_snum:
7f635ab7
PE
161 head = &hashinfo->bhash[inet_bhashfn(net, snum,
162 hashinfo->bhash_size)];
3f421baa
ACM
163 spin_lock(&head->lock);
164 inet_bind_bucket_for_each(tb, node, &head->chain)
09ad9bc7 165 if (net_eq(ib_net(tb), net) && tb->port == snum)
3f421baa
ACM
166 goto tb_found;
167 }
168 tb = NULL;
169 goto tb_not_found;
170tb_found:
171 if (!hlist_empty(&tb->owners)) {
3f421baa 172 if (tb->fastreuse > 0 &&
a9d8f911
EP
173 sk->sk_reuse && sk->sk_state != TCP_LISTEN &&
174 smallest_size == -1) {
3f421baa
ACM
175 goto success;
176 } else {
177 ret = 1;
a9d8f911 178 if (inet_csk(sk)->icsk_af_ops->bind_conflict(sk, tb)) {
5add3009
SH
179 if (sk->sk_reuse && sk->sk_state != TCP_LISTEN &&
180 smallest_size != -1 && --attempts >= 0) {
a9d8f911
EP
181 spin_unlock(&head->lock);
182 goto again;
183 }
3f421baa 184 goto fail_unlock;
a9d8f911 185 }
3f421baa
ACM
186 }
187 }
188tb_not_found:
189 ret = 1;
941b1d22
PE
190 if (!tb && (tb = inet_bind_bucket_create(hashinfo->bind_bucket_cachep,
191 net, head, snum)) == NULL)
3f421baa
ACM
192 goto fail_unlock;
193 if (hlist_empty(&tb->owners)) {
194 if (sk->sk_reuse && sk->sk_state != TCP_LISTEN)
195 tb->fastreuse = 1;
196 else
197 tb->fastreuse = 0;
198 } else if (tb->fastreuse &&
199 (!sk->sk_reuse || sk->sk_state == TCP_LISTEN))
200 tb->fastreuse = 0;
201success:
202 if (!inet_csk(sk)->icsk_bind_hash)
203 inet_bind_hash(sk, tb, snum);
547b792c 204 WARN_ON(inet_csk(sk)->icsk_bind_hash != tb);
e905a9ed 205 ret = 0;
3f421baa
ACM
206
207fail_unlock:
208 spin_unlock(&head->lock);
209fail:
210 local_bh_enable();
211 return ret;
212}
3f421baa
ACM
213EXPORT_SYMBOL_GPL(inet_csk_get_port);
214
215/*
216 * Wait for an incoming connection, avoid race conditions. This must be called
217 * with the socket locked.
218 */
219static int inet_csk_wait_for_connect(struct sock *sk, long timeo)
220{
221 struct inet_connection_sock *icsk = inet_csk(sk);
222 DEFINE_WAIT(wait);
223 int err;
224
225 /*
226 * True wake-one mechanism for incoming connections: only
227 * one process gets woken up, not the 'whole herd'.
228 * Since we do not 'race & poll' for established sockets
229 * anymore, the common case will execute the loop only once.
230 *
231 * Subtle issue: "add_wait_queue_exclusive()" will be added
232 * after any current non-exclusive waiters, and we know that
233 * it will always _stay_ after any new non-exclusive waiters
234 * because all non-exclusive waiters are added at the
235 * beginning of the wait-queue. As such, it's ok to "drop"
236 * our exclusiveness temporarily when we get woken up without
237 * having to remove and re-insert us on the wait queue.
238 */
239 for (;;) {
aa395145 240 prepare_to_wait_exclusive(sk_sleep(sk), &wait,
3f421baa
ACM
241 TASK_INTERRUPTIBLE);
242 release_sock(sk);
243 if (reqsk_queue_empty(&icsk->icsk_accept_queue))
244 timeo = schedule_timeout(timeo);
245 lock_sock(sk);
246 err = 0;
247 if (!reqsk_queue_empty(&icsk->icsk_accept_queue))
248 break;
249 err = -EINVAL;
250 if (sk->sk_state != TCP_LISTEN)
251 break;
252 err = sock_intr_errno(timeo);
253 if (signal_pending(current))
254 break;
255 err = -EAGAIN;
256 if (!timeo)
257 break;
258 }
aa395145 259 finish_wait(sk_sleep(sk), &wait);
3f421baa
ACM
260 return err;
261}
262
263/*
264 * This will accept the next outstanding connection.
265 */
266struct sock *inet_csk_accept(struct sock *sk, int flags, int *err)
267{
268 struct inet_connection_sock *icsk = inet_csk(sk);
269 struct sock *newsk;
270 int error;
271
272 lock_sock(sk);
273
274 /* We need to make sure that this socket is listening,
275 * and that it has something pending.
276 */
277 error = -EINVAL;
278 if (sk->sk_state != TCP_LISTEN)
279 goto out_err;
280
281 /* Find already established connection */
282 if (reqsk_queue_empty(&icsk->icsk_accept_queue)) {
283 long timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
284
285 /* If this is a non blocking socket don't sleep */
286 error = -EAGAIN;
287 if (!timeo)
288 goto out_err;
289
290 error = inet_csk_wait_for_connect(sk, timeo);
291 if (error)
292 goto out_err;
293 }
294
295 newsk = reqsk_queue_get_child(&icsk->icsk_accept_queue, sk);
547b792c 296 WARN_ON(newsk->sk_state == TCP_SYN_RECV);
3f421baa
ACM
297out:
298 release_sock(sk);
299 return newsk;
300out_err:
301 newsk = NULL;
302 *err = error;
303 goto out;
304}
3f421baa
ACM
305EXPORT_SYMBOL(inet_csk_accept);
306
307/*
308 * Using different timers for retransmit, delayed acks and probes
e905a9ed 309 * We may wish use just one timer maintaining a list of expire jiffies
3f421baa
ACM
310 * to optimize.
311 */
312void inet_csk_init_xmit_timers(struct sock *sk,
313 void (*retransmit_handler)(unsigned long),
314 void (*delack_handler)(unsigned long),
315 void (*keepalive_handler)(unsigned long))
316{
317 struct inet_connection_sock *icsk = inet_csk(sk);
318
b24b8a24
PE
319 setup_timer(&icsk->icsk_retransmit_timer, retransmit_handler,
320 (unsigned long)sk);
321 setup_timer(&icsk->icsk_delack_timer, delack_handler,
322 (unsigned long)sk);
323 setup_timer(&sk->sk_timer, keepalive_handler, (unsigned long)sk);
3f421baa
ACM
324 icsk->icsk_pending = icsk->icsk_ack.pending = 0;
325}
3f421baa
ACM
326EXPORT_SYMBOL(inet_csk_init_xmit_timers);
327
328void inet_csk_clear_xmit_timers(struct sock *sk)
329{
330 struct inet_connection_sock *icsk = inet_csk(sk);
331
332 icsk->icsk_pending = icsk->icsk_ack.pending = icsk->icsk_ack.blocked = 0;
333
334 sk_stop_timer(sk, &icsk->icsk_retransmit_timer);
335 sk_stop_timer(sk, &icsk->icsk_delack_timer);
336 sk_stop_timer(sk, &sk->sk_timer);
337}
3f421baa
ACM
338EXPORT_SYMBOL(inet_csk_clear_xmit_timers);
339
340void inet_csk_delete_keepalive_timer(struct sock *sk)
341{
342 sk_stop_timer(sk, &sk->sk_timer);
343}
3f421baa
ACM
344EXPORT_SYMBOL(inet_csk_delete_keepalive_timer);
345
346void inet_csk_reset_keepalive_timer(struct sock *sk, unsigned long len)
347{
348 sk_reset_timer(sk, &sk->sk_timer, jiffies + len);
349}
3f421baa
ACM
350EXPORT_SYMBOL(inet_csk_reset_keepalive_timer);
351
d9319100 352struct dst_entry *inet_csk_route_req(struct sock *sk,
3f421baa
ACM
353 const struct request_sock *req)
354{
355 struct rtable *rt;
356 const struct inet_request_sock *ireq = inet_rsk(req);
f6d8bd05 357 struct ip_options_rcu *opt = inet_rsk(req)->opt;
84a3aa00 358 struct net *net = sock_net(sk);
e79d9bc7 359 struct flowi4 fl4;
3f421baa 360
e79d9bc7
DM
361 flowi4_init_output(&fl4, sk->sk_bound_dev_if, sk->sk_mark,
362 RT_CONN_FLAGS(sk), RT_SCOPE_UNIVERSE,
363 sk->sk_protocol, inet_sk_flowi_flags(sk),
f6d8bd05 364 (opt && opt->opt.srr) ? opt->opt.faddr : ireq->rmt_addr,
e79d9bc7 365 ireq->loc_addr, ireq->rmt_port, inet_sk(sk)->inet_sport);
9d6ec938
DM
366 security_req_classify_flow(req, flowi4_to_flowi(&fl4));
367 rt = ip_route_output_flow(net, &fl4, sk);
b23dd4fe 368 if (IS_ERR(rt))
857a6e0a 369 goto no_route;
072d8c94 370 if (opt && opt->opt.is_strictroute && fl4.daddr != rt->rt_gateway)
857a6e0a 371 goto route_err;
d8d1f30b 372 return &rt->dst;
857a6e0a
IJ
373
374route_err:
375 ip_rt_put(rt);
376no_route:
377 IP_INC_STATS_BH(net, IPSTATS_MIB_OUTNOROUTES);
378 return NULL;
3f421baa 379}
3f421baa
ACM
380EXPORT_SYMBOL_GPL(inet_csk_route_req);
381
6b72977b 382static inline u32 inet_synq_hash(const __be32 raddr, const __be16 rport,
72a3effa 383 const u32 rnd, const u32 synq_hsize)
3f421baa 384{
6b72977b 385 return jhash_2words((__force u32)raddr, (__force u32)rport, rnd) & (synq_hsize - 1);
3f421baa
ACM
386}
387
388#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
389#define AF_INET_FAMILY(fam) ((fam) == AF_INET)
390#else
391#define AF_INET_FAMILY(fam) 1
392#endif
393
394struct request_sock *inet_csk_search_req(const struct sock *sk,
395 struct request_sock ***prevp,
6b72977b 396 const __be16 rport, const __be32 raddr,
7f25afbb 397 const __be32 laddr)
3f421baa
ACM
398{
399 const struct inet_connection_sock *icsk = inet_csk(sk);
400 struct listen_sock *lopt = icsk->icsk_accept_queue.listen_opt;
401 struct request_sock *req, **prev;
402
403 for (prev = &lopt->syn_table[inet_synq_hash(raddr, rport, lopt->hash_rnd,
404 lopt->nr_table_entries)];
405 (req = *prev) != NULL;
406 prev = &req->dl_next) {
407 const struct inet_request_sock *ireq = inet_rsk(req);
408
409 if (ireq->rmt_port == rport &&
410 ireq->rmt_addr == raddr &&
411 ireq->loc_addr == laddr &&
412 AF_INET_FAMILY(req->rsk_ops->family)) {
547b792c 413 WARN_ON(req->sk);
3f421baa
ACM
414 *prevp = prev;
415 break;
416 }
417 }
418
419 return req;
420}
3f421baa
ACM
421EXPORT_SYMBOL_GPL(inet_csk_search_req);
422
423void inet_csk_reqsk_queue_hash_add(struct sock *sk, struct request_sock *req,
c2977c22 424 unsigned long timeout)
3f421baa
ACM
425{
426 struct inet_connection_sock *icsk = inet_csk(sk);
427 struct listen_sock *lopt = icsk->icsk_accept_queue.listen_opt;
428 const u32 h = inet_synq_hash(inet_rsk(req)->rmt_addr, inet_rsk(req)->rmt_port,
429 lopt->hash_rnd, lopt->nr_table_entries);
430
431 reqsk_queue_hash_req(&icsk->icsk_accept_queue, h, req, timeout);
432 inet_csk_reqsk_queue_added(sk, timeout);
433}
4bc2f18b 434EXPORT_SYMBOL_GPL(inet_csk_reqsk_queue_hash_add);
3f421baa 435
a019d6fe
ACM
436/* Only thing we need from tcp.h */
437extern int sysctl_tcp_synack_retries;
438
9f1d2604 439
0c3d79bc
JA
440/* Decide when to expire the request and when to resend SYN-ACK */
441static inline void syn_ack_recalc(struct request_sock *req, const int thresh,
442 const int max_retries,
443 const u8 rskq_defer_accept,
444 int *expire, int *resend)
445{
446 if (!rskq_defer_accept) {
447 *expire = req->retrans >= thresh;
448 *resend = 1;
449 return;
450 }
451 *expire = req->retrans >= thresh &&
452 (!inet_rsk(req)->acked || req->retrans >= max_retries);
453 /*
454 * Do not resend while waiting for data after ACK,
455 * start to resend on end of deferring period to give
456 * last chance for data or ACK to create established socket.
457 */
458 *resend = !inet_rsk(req)->acked ||
459 req->retrans >= rskq_defer_accept - 1;
460}
461
a019d6fe
ACM
462void inet_csk_reqsk_queue_prune(struct sock *parent,
463 const unsigned long interval,
464 const unsigned long timeout,
465 const unsigned long max_rto)
466{
467 struct inet_connection_sock *icsk = inet_csk(parent);
468 struct request_sock_queue *queue = &icsk->icsk_accept_queue;
469 struct listen_sock *lopt = queue->listen_opt;
ec0a1966
DM
470 int max_retries = icsk->icsk_syn_retries ? : sysctl_tcp_synack_retries;
471 int thresh = max_retries;
a019d6fe
ACM
472 unsigned long now = jiffies;
473 struct request_sock **reqp, *req;
474 int i, budget;
475
476 if (lopt == NULL || lopt->qlen == 0)
477 return;
478
479 /* Normally all the openreqs are young and become mature
480 * (i.e. converted to established socket) for first timeout.
481 * If synack was not acknowledged for 3 seconds, it means
482 * one of the following things: synack was lost, ack was lost,
483 * rtt is high or nobody planned to ack (i.e. synflood).
484 * When server is a bit loaded, queue is populated with old
485 * open requests, reducing effective size of queue.
486 * When server is well loaded, queue size reduces to zero
487 * after several minutes of work. It is not synflood,
488 * it is normal operation. The solution is pruning
489 * too old entries overriding normal timeout, when
490 * situation becomes dangerous.
491 *
492 * Essentially, we reserve half of room for young
493 * embrions; and abort old ones without pity, if old
494 * ones are about to clog our table.
495 */
496 if (lopt->qlen>>(lopt->max_qlen_log-1)) {
497 int young = (lopt->qlen_young<<1);
498
499 while (thresh > 2) {
500 if (lopt->qlen < young)
501 break;
502 thresh--;
503 young <<= 1;
504 }
505 }
506
ec0a1966
DM
507 if (queue->rskq_defer_accept)
508 max_retries = queue->rskq_defer_accept;
509
a019d6fe
ACM
510 budget = 2 * (lopt->nr_table_entries / (timeout / interval));
511 i = lopt->clock_hand;
512
513 do {
514 reqp=&lopt->syn_table[i];
515 while ((req = *reqp) != NULL) {
516 if (time_after_eq(now, req->expires)) {
0c3d79bc
JA
517 int expire = 0, resend = 0;
518
519 syn_ack_recalc(req, thresh, max_retries,
520 queue->rskq_defer_accept,
521 &expire, &resend);
72659ecc
OP
522 if (req->rsk_ops->syn_ack_timeout)
523 req->rsk_ops->syn_ack_timeout(parent, req);
0c3d79bc
JA
524 if (!expire &&
525 (!resend ||
e6b4d113 526 !req->rsk_ops->rtx_syn_ack(parent, req, NULL) ||
0c3d79bc 527 inet_rsk(req)->acked)) {
a019d6fe
ACM
528 unsigned long timeo;
529
530 if (req->retrans++ == 0)
531 lopt->qlen_young--;
532 timeo = min((timeout << req->retrans), max_rto);
533 req->expires = now + timeo;
534 reqp = &req->dl_next;
535 continue;
536 }
537
538 /* Drop this request */
539 inet_csk_reqsk_queue_unlink(parent, req, reqp);
540 reqsk_queue_removed(queue, req);
541 reqsk_free(req);
542 continue;
543 }
544 reqp = &req->dl_next;
545 }
546
547 i = (i + 1) & (lopt->nr_table_entries - 1);
548
549 } while (--budget > 0);
550
551 lopt->clock_hand = i;
552
553 if (lopt->qlen)
554 inet_csk_reset_keepalive_timer(parent, interval);
555}
a019d6fe
ACM
556EXPORT_SYMBOL_GPL(inet_csk_reqsk_queue_prune);
557
9f1d2604 558struct sock *inet_csk_clone(struct sock *sk, const struct request_sock *req,
dd0fc66f 559 const gfp_t priority)
9f1d2604
ACM
560{
561 struct sock *newsk = sk_clone(sk, priority);
562
563 if (newsk != NULL) {
564 struct inet_connection_sock *newicsk = inet_csk(newsk);
565
566 newsk->sk_state = TCP_SYN_RECV;
567 newicsk->icsk_bind_hash = NULL;
568
c720c7e8
ED
569 inet_sk(newsk)->inet_dport = inet_rsk(req)->rmt_port;
570 inet_sk(newsk)->inet_num = ntohs(inet_rsk(req)->loc_port);
571 inet_sk(newsk)->inet_sport = inet_rsk(req)->loc_port;
9f1d2604
ACM
572 newsk->sk_write_space = sk_stream_write_space;
573
574 newicsk->icsk_retransmits = 0;
6687e988
ACM
575 newicsk->icsk_backoff = 0;
576 newicsk->icsk_probes_out = 0;
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ACM
577
578 /* Deinitialize accept_queue to trap illegal accesses. */
579 memset(&newicsk->icsk_accept_queue, 0, sizeof(newicsk->icsk_accept_queue));
4237c75c
VY
580
581 security_inet_csk_clone(newsk, req);
9f1d2604
ACM
582 }
583 return newsk;
584}
9f1d2604 585EXPORT_SYMBOL_GPL(inet_csk_clone);
a019d6fe
ACM
586
587/*
588 * At this point, there should be no process reference to this
589 * socket, and thus no user references at all. Therefore we
590 * can assume the socket waitqueue is inactive and nobody will
591 * try to jump onto it.
592 */
593void inet_csk_destroy_sock(struct sock *sk)
594{
547b792c
IJ
595 WARN_ON(sk->sk_state != TCP_CLOSE);
596 WARN_ON(!sock_flag(sk, SOCK_DEAD));
a019d6fe
ACM
597
598 /* It cannot be in hash table! */
547b792c 599 WARN_ON(!sk_unhashed(sk));
a019d6fe 600
c720c7e8
ED
601 /* If it has not 0 inet_sk(sk)->inet_num, it must be bound */
602 WARN_ON(inet_sk(sk)->inet_num && !inet_csk(sk)->icsk_bind_hash);
a019d6fe
ACM
603
604 sk->sk_prot->destroy(sk);
605
606 sk_stream_kill_queues(sk);
607
608 xfrm_sk_free_policy(sk);
609
610 sk_refcnt_debug_release(sk);
611
dd24c001 612 percpu_counter_dec(sk->sk_prot->orphan_count);
a019d6fe
ACM
613 sock_put(sk);
614}
a019d6fe
ACM
615EXPORT_SYMBOL(inet_csk_destroy_sock);
616
617int inet_csk_listen_start(struct sock *sk, const int nr_table_entries)
618{
619 struct inet_sock *inet = inet_sk(sk);
620 struct inet_connection_sock *icsk = inet_csk(sk);
621 int rc = reqsk_queue_alloc(&icsk->icsk_accept_queue, nr_table_entries);
622
623 if (rc != 0)
624 return rc;
625
626 sk->sk_max_ack_backlog = 0;
627 sk->sk_ack_backlog = 0;
628 inet_csk_delack_init(sk);
629
630 /* There is race window here: we announce ourselves listening,
631 * but this transition is still not validated by get_port().
632 * It is OK, because this socket enters to hash table only
633 * after validation is complete.
634 */
635 sk->sk_state = TCP_LISTEN;
c720c7e8
ED
636 if (!sk->sk_prot->get_port(sk, inet->inet_num)) {
637 inet->inet_sport = htons(inet->inet_num);
a019d6fe
ACM
638
639 sk_dst_reset(sk);
640 sk->sk_prot->hash(sk);
641
642 return 0;
643 }
644
645 sk->sk_state = TCP_CLOSE;
646 __reqsk_queue_destroy(&icsk->icsk_accept_queue);
647 return -EADDRINUSE;
648}
a019d6fe
ACM
649EXPORT_SYMBOL_GPL(inet_csk_listen_start);
650
651/*
652 * This routine closes sockets which have been at least partially
653 * opened, but not yet accepted.
654 */
655void inet_csk_listen_stop(struct sock *sk)
656{
657 struct inet_connection_sock *icsk = inet_csk(sk);
658 struct request_sock *acc_req;
659 struct request_sock *req;
660
661 inet_csk_delete_keepalive_timer(sk);
662
663 /* make all the listen_opt local to us */
664 acc_req = reqsk_queue_yank_acceptq(&icsk->icsk_accept_queue);
665
666 /* Following specs, it would be better either to send FIN
667 * (and enter FIN-WAIT-1, it is normal close)
668 * or to send active reset (abort).
669 * Certainly, it is pretty dangerous while synflood, but it is
670 * bad justification for our negligence 8)
671 * To be honest, we are not able to make either
672 * of the variants now. --ANK
673 */
674 reqsk_queue_destroy(&icsk->icsk_accept_queue);
675
676 while ((req = acc_req) != NULL) {
677 struct sock *child = req->sk;
678
679 acc_req = req->dl_next;
680
681 local_bh_disable();
682 bh_lock_sock(child);
547b792c 683 WARN_ON(sock_owned_by_user(child));
a019d6fe
ACM
684 sock_hold(child);
685
686 sk->sk_prot->disconnect(child, O_NONBLOCK);
687
688 sock_orphan(child);
689
eb4dea58
HX
690 percpu_counter_inc(sk->sk_prot->orphan_count);
691
a019d6fe
ACM
692 inet_csk_destroy_sock(child);
693
694 bh_unlock_sock(child);
695 local_bh_enable();
696 sock_put(child);
697
698 sk_acceptq_removed(sk);
699 __reqsk_free(req);
700 }
547b792c 701 WARN_ON(sk->sk_ack_backlog);
a019d6fe 702}
a019d6fe 703EXPORT_SYMBOL_GPL(inet_csk_listen_stop);
af05dc93
ACM
704
705void inet_csk_addr2sockaddr(struct sock *sk, struct sockaddr *uaddr)
706{
707 struct sockaddr_in *sin = (struct sockaddr_in *)uaddr;
708 const struct inet_sock *inet = inet_sk(sk);
709
710 sin->sin_family = AF_INET;
c720c7e8
ED
711 sin->sin_addr.s_addr = inet->inet_daddr;
712 sin->sin_port = inet->inet_dport;
af05dc93 713}
af05dc93 714EXPORT_SYMBOL_GPL(inet_csk_addr2sockaddr);
c4d93909 715
dec73ff0
ACM
716#ifdef CONFIG_COMPAT
717int inet_csk_compat_getsockopt(struct sock *sk, int level, int optname,
718 char __user *optval, int __user *optlen)
719{
dbeff12b 720 const struct inet_connection_sock *icsk = inet_csk(sk);
dec73ff0
ACM
721
722 if (icsk->icsk_af_ops->compat_getsockopt != NULL)
723 return icsk->icsk_af_ops->compat_getsockopt(sk, level, optname,
724 optval, optlen);
725 return icsk->icsk_af_ops->getsockopt(sk, level, optname,
726 optval, optlen);
727}
dec73ff0
ACM
728EXPORT_SYMBOL_GPL(inet_csk_compat_getsockopt);
729
730int inet_csk_compat_setsockopt(struct sock *sk, int level, int optname,
b7058842 731 char __user *optval, unsigned int optlen)
dec73ff0 732{
dbeff12b 733 const struct inet_connection_sock *icsk = inet_csk(sk);
dec73ff0
ACM
734
735 if (icsk->icsk_af_ops->compat_setsockopt != NULL)
736 return icsk->icsk_af_ops->compat_setsockopt(sk, level, optname,
737 optval, optlen);
738 return icsk->icsk_af_ops->setsockopt(sk, level, optname,
739 optval, optlen);
740}
dec73ff0
ACM
741EXPORT_SYMBOL_GPL(inet_csk_compat_setsockopt);
742#endif