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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#include <net/tcp.h>
27#include <net/sock_reuseport.h>
28
29#ifdef INET_CSK_DEBUG
30const char inet_csk_timer_bug_msg[] = "inet_csk BUG: unknown timer value\n";
31EXPORT_SYMBOL(inet_csk_timer_bug_msg);
32#endif
33
34void inet_get_local_port_range(struct net *net, int *low, int *high)
35{
36 unsigned int seq;
37
38 do {
39 seq = read_seqbegin(&net->ipv4.ip_local_ports.lock);
40
41 *low = net->ipv4.ip_local_ports.range[0];
42 *high = net->ipv4.ip_local_ports.range[1];
43 } while (read_seqretry(&net->ipv4.ip_local_ports.lock, seq));
44}
45EXPORT_SYMBOL(inet_get_local_port_range);
46
47int inet_csk_bind_conflict(const struct sock *sk,
48 const struct inet_bind_bucket *tb, bool relax,
49 bool reuseport_ok)
50{
51 struct sock *sk2;
52 bool reuse = sk->sk_reuse;
53 bool reuseport = !!sk->sk_reuseport && reuseport_ok;
54 kuid_t uid = sock_i_uid((struct sock *)sk);
55
56
57
58
59
60
61
62
63 sk_for_each_bound(sk2, &tb->owners) {
64 if (sk != sk2 &&
65 !inet_v6_ipv6only(sk2) &&
66 (!sk->sk_bound_dev_if ||
67 !sk2->sk_bound_dev_if ||
68 sk->sk_bound_dev_if == sk2->sk_bound_dev_if)) {
69 if ((!reuse || !sk2->sk_reuse ||
70 sk2->sk_state == TCP_LISTEN) &&
71 (!reuseport || !sk2->sk_reuseport ||
72 rcu_access_pointer(sk->sk_reuseport_cb) ||
73 (sk2->sk_state != TCP_TIME_WAIT &&
74 !uid_eq(uid, sock_i_uid(sk2))))) {
75
76 if (!sk2->sk_rcv_saddr || !sk->sk_rcv_saddr ||
77 sk2->sk_rcv_saddr == sk->sk_rcv_saddr)
78 break;
79 }
80 if (!relax && reuse && sk2->sk_reuse &&
81 sk2->sk_state != TCP_LISTEN) {
82
83 if (!sk2->sk_rcv_saddr || !sk->sk_rcv_saddr ||
84 sk2->sk_rcv_saddr == sk->sk_rcv_saddr)
85 break;
86 }
87 }
88 }
89 return sk2 != NULL;
90}
91EXPORT_SYMBOL_GPL(inet_csk_bind_conflict);
92
93
94
95
96
97int inet_csk_get_port(struct sock *sk, unsigned short snum)
98{
99 bool reuse = sk->sk_reuse && sk->sk_state != TCP_LISTEN;
100 struct inet_hashinfo *hinfo = sk->sk_prot->h.hashinfo;
101 int ret = 1, attempts = 5, port = snum;
102 int smallest_size = -1, smallest_port;
103 struct inet_bind_hashbucket *head;
104 struct net *net = sock_net(sk);
105 int i, low, high, attempt_half;
106 struct inet_bind_bucket *tb;
107 kuid_t uid = sock_i_uid(sk);
108 u32 remaining, offset;
109 bool reuseport_ok = !!snum;
110
111 if (port) {
112have_port:
113 head = &hinfo->bhash[inet_bhashfn(net, port,
114 hinfo->bhash_size)];
115 spin_lock_bh(&head->lock);
116 inet_bind_bucket_for_each(tb, &head->chain)
117 if (net_eq(ib_net(tb), net) && tb->port == port)
118 goto tb_found;
119
120 goto tb_not_found;
121 }
122again:
123 attempt_half = (sk->sk_reuse == SK_CAN_REUSE) ? 1 : 0;
124other_half_scan:
125 inet_get_local_port_range(net, &low, &high);
126 high++;
127 if (high - low < 4)
128 attempt_half = 0;
129 if (attempt_half) {
130 int half = low + (((high - low) >> 2) << 1);
131
132 if (attempt_half == 1)
133 high = half;
134 else
135 low = half;
136 }
137 remaining = high - low;
138 if (likely(remaining > 1))
139 remaining &= ~1U;
140
141 offset = prandom_u32() % remaining;
142
143
144
145 offset |= 1U;
146 smallest_size = -1;
147 smallest_port = low;
148
149other_parity_scan:
150 port = low + offset;
151 for (i = 0; i < remaining; i += 2, port += 2) {
152 if (unlikely(port >= high))
153 port -= remaining;
154 if (inet_is_local_reserved_port(net, port))
155 continue;
156 head = &hinfo->bhash[inet_bhashfn(net, port,
157 hinfo->bhash_size)];
158 spin_lock_bh(&head->lock);
159 inet_bind_bucket_for_each(tb, &head->chain)
160 if (net_eq(ib_net(tb), net) && tb->port == port) {
161 if (((tb->fastreuse > 0 && reuse) ||
162 (tb->fastreuseport > 0 &&
163 sk->sk_reuseport &&
164 !rcu_access_pointer(sk->sk_reuseport_cb) &&
165 uid_eq(tb->fastuid, uid))) &&
166 (tb->num_owners < smallest_size || smallest_size == -1)) {
167 smallest_size = tb->num_owners;
168 smallest_port = port;
169 }
170 if (!inet_csk(sk)->icsk_af_ops->bind_conflict(sk, tb, false,
171 reuseport_ok))
172 goto tb_found;
173 goto next_port;
174 }
175 goto tb_not_found;
176next_port:
177 spin_unlock_bh(&head->lock);
178 cond_resched();
179 }
180
181 if (smallest_size != -1) {
182 port = smallest_port;
183 goto have_port;
184 }
185 offset--;
186 if (!(offset & 1))
187 goto other_parity_scan;
188
189 if (attempt_half == 1) {
190
191 attempt_half = 2;
192 goto other_half_scan;
193 }
194 return ret;
195
196tb_not_found:
197 tb = inet_bind_bucket_create(hinfo->bind_bucket_cachep,
198 net, head, port);
199 if (!tb)
200 goto fail_unlock;
201tb_found:
202 if (!hlist_empty(&tb->owners)) {
203 if (sk->sk_reuse == SK_FORCE_REUSE)
204 goto success;
205
206 if (((tb->fastreuse > 0 && reuse) ||
207 (tb->fastreuseport > 0 &&
208 !rcu_access_pointer(sk->sk_reuseport_cb) &&
209 sk->sk_reuseport && uid_eq(tb->fastuid, uid))) &&
210 smallest_size == -1)
211 goto success;
212 if (inet_csk(sk)->icsk_af_ops->bind_conflict(sk, tb, true,
213 reuseport_ok)) {
214 if ((reuse ||
215 (tb->fastreuseport > 0 &&
216 sk->sk_reuseport &&
217 !rcu_access_pointer(sk->sk_reuseport_cb) &&
218 uid_eq(tb->fastuid, uid))) &&
219 !snum && smallest_size != -1 && --attempts >= 0) {
220 spin_unlock_bh(&head->lock);
221 goto again;
222 }
223 goto fail_unlock;
224 }
225 if (!reuse)
226 tb->fastreuse = 0;
227 if (!sk->sk_reuseport || !uid_eq(tb->fastuid, uid))
228 tb->fastreuseport = 0;
229 } else {
230 tb->fastreuse = reuse;
231 if (sk->sk_reuseport) {
232 tb->fastreuseport = 1;
233 tb->fastuid = uid;
234 } else {
235 tb->fastreuseport = 0;
236 }
237 }
238success:
239 if (!inet_csk(sk)->icsk_bind_hash)
240 inet_bind_hash(sk, tb, port);
241 WARN_ON(inet_csk(sk)->icsk_bind_hash != tb);
242 ret = 0;
243
244fail_unlock:
245 spin_unlock_bh(&head->lock);
246 return ret;
247}
248EXPORT_SYMBOL_GPL(inet_csk_get_port);
249
250
251
252
253
254static int inet_csk_wait_for_connect(struct sock *sk, long timeo)
255{
256 struct inet_connection_sock *icsk = inet_csk(sk);
257 DEFINE_WAIT(wait);
258 int err;
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274 for (;;) {
275 prepare_to_wait_exclusive(sk_sleep(sk), &wait,
276 TASK_INTERRUPTIBLE);
277 release_sock(sk);
278 if (reqsk_queue_empty(&icsk->icsk_accept_queue))
279 timeo = schedule_timeout(timeo);
280 sched_annotate_sleep();
281 lock_sock(sk);
282 err = 0;
283 if (!reqsk_queue_empty(&icsk->icsk_accept_queue))
284 break;
285 err = -EINVAL;
286 if (sk->sk_state != TCP_LISTEN)
287 break;
288 err = sock_intr_errno(timeo);
289 if (signal_pending(current))
290 break;
291 err = -EAGAIN;
292 if (!timeo)
293 break;
294 }
295 finish_wait(sk_sleep(sk), &wait);
296 return err;
297}
298
299
300
301
302struct sock *inet_csk_accept(struct sock *sk, int flags, int *err)
303{
304 struct inet_connection_sock *icsk = inet_csk(sk);
305 struct request_sock_queue *queue = &icsk->icsk_accept_queue;
306 struct request_sock *req;
307 struct sock *newsk;
308 int error;
309
310 lock_sock(sk);
311
312
313
314
315 error = -EINVAL;
316 if (sk->sk_state != TCP_LISTEN)
317 goto out_err;
318
319
320 if (reqsk_queue_empty(queue)) {
321 long timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
322
323
324 error = -EAGAIN;
325 if (!timeo)
326 goto out_err;
327
328 error = inet_csk_wait_for_connect(sk, timeo);
329 if (error)
330 goto out_err;
331 }
332 req = reqsk_queue_remove(queue, sk);
333 newsk = req->sk;
334
335 if (sk->sk_protocol == IPPROTO_TCP &&
336 tcp_rsk(req)->tfo_listener) {
337 spin_lock_bh(&queue->fastopenq.lock);
338 if (tcp_rsk(req)->tfo_listener) {
339
340
341
342
343
344
345 req->sk = NULL;
346 req = NULL;
347 }
348 spin_unlock_bh(&queue->fastopenq.lock);
349 }
350out:
351 release_sock(sk);
352 if (req)
353 reqsk_put(req);
354 return newsk;
355out_err:
356 newsk = NULL;
357 req = NULL;
358 *err = error;
359 goto out;
360}
361EXPORT_SYMBOL(inet_csk_accept);
362
363
364
365
366
367
368void inet_csk_init_xmit_timers(struct sock *sk,
369 void (*retransmit_handler)(unsigned long),
370 void (*delack_handler)(unsigned long),
371 void (*keepalive_handler)(unsigned long))
372{
373 struct inet_connection_sock *icsk = inet_csk(sk);
374
375 setup_timer(&icsk->icsk_retransmit_timer, retransmit_handler,
376 (unsigned long)sk);
377 setup_timer(&icsk->icsk_delack_timer, delack_handler,
378 (unsigned long)sk);
379 setup_timer(&sk->sk_timer, keepalive_handler, (unsigned long)sk);
380 icsk->icsk_pending = icsk->icsk_ack.pending = 0;
381}
382EXPORT_SYMBOL(inet_csk_init_xmit_timers);
383
384void inet_csk_clear_xmit_timers(struct sock *sk)
385{
386 struct inet_connection_sock *icsk = inet_csk(sk);
387
388 icsk->icsk_pending = icsk->icsk_ack.pending = icsk->icsk_ack.blocked = 0;
389
390 sk_stop_timer(sk, &icsk->icsk_retransmit_timer);
391 sk_stop_timer(sk, &icsk->icsk_delack_timer);
392 sk_stop_timer(sk, &sk->sk_timer);
393}
394EXPORT_SYMBOL(inet_csk_clear_xmit_timers);
395
396void inet_csk_delete_keepalive_timer(struct sock *sk)
397{
398 sk_stop_timer(sk, &sk->sk_timer);
399}
400EXPORT_SYMBOL(inet_csk_delete_keepalive_timer);
401
402void inet_csk_reset_keepalive_timer(struct sock *sk, unsigned long len)
403{
404 sk_reset_timer(sk, &sk->sk_timer, jiffies + len);
405}
406EXPORT_SYMBOL(inet_csk_reset_keepalive_timer);
407
408struct dst_entry *inet_csk_route_req(const struct sock *sk,
409 struct flowi4 *fl4,
410 const struct request_sock *req)
411{
412 const struct inet_request_sock *ireq = inet_rsk(req);
413 struct net *net = read_pnet(&ireq->ireq_net);
414 struct ip_options_rcu *opt = ireq->opt;
415 struct rtable *rt;
416
417 flowi4_init_output(fl4, ireq->ir_iif, ireq->ir_mark,
418 RT_CONN_FLAGS(sk), RT_SCOPE_UNIVERSE,
419 sk->sk_protocol, inet_sk_flowi_flags(sk),
420 (opt && opt->opt.srr) ? opt->opt.faddr : ireq->ir_rmt_addr,
421 ireq->ir_loc_addr, ireq->ir_rmt_port,
422 htons(ireq->ir_num), sk->sk_uid);
423 security_req_classify_flow(req, flowi4_to_flowi(fl4));
424 rt = ip_route_output_flow(net, fl4, sk);
425 if (IS_ERR(rt))
426 goto no_route;
427 if (opt && opt->opt.is_strictroute && rt->rt_uses_gateway)
428 goto route_err;
429 return &rt->dst;
430
431route_err:
432 ip_rt_put(rt);
433no_route:
434 __IP_INC_STATS(net, IPSTATS_MIB_OUTNOROUTES);
435 return NULL;
436}
437EXPORT_SYMBOL_GPL(inet_csk_route_req);
438
439struct dst_entry *inet_csk_route_child_sock(const struct sock *sk,
440 struct sock *newsk,
441 const struct request_sock *req)
442{
443 const struct inet_request_sock *ireq = inet_rsk(req);
444 struct net *net = read_pnet(&ireq->ireq_net);
445 struct inet_sock *newinet = inet_sk(newsk);
446 struct ip_options_rcu *opt;
447 struct flowi4 *fl4;
448 struct rtable *rt;
449
450 fl4 = &newinet->cork.fl.u.ip4;
451
452 rcu_read_lock();
453 opt = rcu_dereference(newinet->inet_opt);
454 flowi4_init_output(fl4, ireq->ir_iif, ireq->ir_mark,
455 RT_CONN_FLAGS(sk), RT_SCOPE_UNIVERSE,
456 sk->sk_protocol, inet_sk_flowi_flags(sk),
457 (opt && opt->opt.srr) ? opt->opt.faddr : ireq->ir_rmt_addr,
458 ireq->ir_loc_addr, ireq->ir_rmt_port,
459 htons(ireq->ir_num), sk->sk_uid);
460 security_req_classify_flow(req, flowi4_to_flowi(fl4));
461 rt = ip_route_output_flow(net, fl4, sk);
462 if (IS_ERR(rt))
463 goto no_route;
464 if (opt && opt->opt.is_strictroute && rt->rt_uses_gateway)
465 goto route_err;
466 rcu_read_unlock();
467 return &rt->dst;
468
469route_err:
470 ip_rt_put(rt);
471no_route:
472 rcu_read_unlock();
473 __IP_INC_STATS(net, IPSTATS_MIB_OUTNOROUTES);
474 return NULL;
475}
476EXPORT_SYMBOL_GPL(inet_csk_route_child_sock);
477
478#if IS_ENABLED(CONFIG_IPV6)
479#define AF_INET_FAMILY(fam) ((fam) == AF_INET)
480#else
481#define AF_INET_FAMILY(fam) true
482#endif
483
484
485static inline void syn_ack_recalc(struct request_sock *req, const int thresh,
486 const int max_retries,
487 const u8 rskq_defer_accept,
488 int *expire, int *resend)
489{
490 if (!rskq_defer_accept) {
491 *expire = req->num_timeout >= thresh;
492 *resend = 1;
493 return;
494 }
495 *expire = req->num_timeout >= thresh &&
496 (!inet_rsk(req)->acked || req->num_timeout >= max_retries);
497
498
499
500
501
502 *resend = !inet_rsk(req)->acked ||
503 req->num_timeout >= rskq_defer_accept - 1;
504}
505
506int inet_rtx_syn_ack(const struct sock *parent, struct request_sock *req)
507{
508 int err = req->rsk_ops->rtx_syn_ack(parent, req);
509
510 if (!err)
511 req->num_retrans++;
512 return err;
513}
514EXPORT_SYMBOL(inet_rtx_syn_ack);
515
516
517static bool reqsk_queue_unlink(struct request_sock_queue *queue,
518 struct request_sock *req)
519{
520 struct inet_hashinfo *hashinfo = req_to_sk(req)->sk_prot->h.hashinfo;
521 bool found = false;
522
523 if (sk_hashed(req_to_sk(req))) {
524 spinlock_t *lock = inet_ehash_lockp(hashinfo, req->rsk_hash);
525
526 spin_lock(lock);
527 found = __sk_nulls_del_node_init_rcu(req_to_sk(req));
528 spin_unlock(lock);
529 }
530 if (timer_pending(&req->rsk_timer) && del_timer_sync(&req->rsk_timer))
531 reqsk_put(req);
532 return found;
533}
534
535void inet_csk_reqsk_queue_drop(struct sock *sk, struct request_sock *req)
536{
537 if (reqsk_queue_unlink(&inet_csk(sk)->icsk_accept_queue, req)) {
538 reqsk_queue_removed(&inet_csk(sk)->icsk_accept_queue, req);
539 reqsk_put(req);
540 }
541}
542EXPORT_SYMBOL(inet_csk_reqsk_queue_drop);
543
544void inet_csk_reqsk_queue_drop_and_put(struct sock *sk, struct request_sock *req)
545{
546 inet_csk_reqsk_queue_drop(sk, req);
547 reqsk_put(req);
548}
549EXPORT_SYMBOL(inet_csk_reqsk_queue_drop_and_put);
550
551static void reqsk_timer_handler(unsigned long data)
552{
553 struct request_sock *req = (struct request_sock *)data;
554 struct sock *sk_listener = req->rsk_listener;
555 struct net *net = sock_net(sk_listener);
556 struct inet_connection_sock *icsk = inet_csk(sk_listener);
557 struct request_sock_queue *queue = &icsk->icsk_accept_queue;
558 int qlen, expire = 0, resend = 0;
559 int max_retries, thresh;
560 u8 defer_accept;
561
562 if (sk_state_load(sk_listener) != TCP_LISTEN)
563 goto drop;
564
565 max_retries = icsk->icsk_syn_retries ? : net->ipv4.sysctl_tcp_synack_retries;
566 thresh = max_retries;
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584 qlen = reqsk_queue_len(queue);
585 if ((qlen << 1) > max(8U, sk_listener->sk_max_ack_backlog)) {
586 int young = reqsk_queue_len_young(queue) << 1;
587
588 while (thresh > 2) {
589 if (qlen < young)
590 break;
591 thresh--;
592 young <<= 1;
593 }
594 }
595 defer_accept = READ_ONCE(queue->rskq_defer_accept);
596 if (defer_accept)
597 max_retries = defer_accept;
598 syn_ack_recalc(req, thresh, max_retries, defer_accept,
599 &expire, &resend);
600 req->rsk_ops->syn_ack_timeout(req);
601 if (!expire &&
602 (!resend ||
603 !inet_rtx_syn_ack(sk_listener, req) ||
604 inet_rsk(req)->acked)) {
605 unsigned long timeo;
606
607 if (req->num_timeout++ == 0)
608 atomic_dec(&queue->young);
609 timeo = min(TCP_TIMEOUT_INIT << req->num_timeout, TCP_RTO_MAX);
610 mod_timer(&req->rsk_timer, jiffies + timeo);
611 return;
612 }
613drop:
614 inet_csk_reqsk_queue_drop_and_put(sk_listener, req);
615}
616
617static void reqsk_queue_hash_req(struct request_sock *req,
618 unsigned long timeout)
619{
620 req->num_retrans = 0;
621 req->num_timeout = 0;
622 req->sk = NULL;
623
624 setup_pinned_timer(&req->rsk_timer, reqsk_timer_handler,
625 (unsigned long)req);
626 mod_timer(&req->rsk_timer, jiffies + timeout);
627
628 inet_ehash_insert(req_to_sk(req), NULL);
629
630
631
632 smp_wmb();
633 atomic_set(&req->rsk_refcnt, 2 + 1);
634}
635
636void inet_csk_reqsk_queue_hash_add(struct sock *sk, struct request_sock *req,
637 unsigned long timeout)
638{
639 reqsk_queue_hash_req(req, timeout);
640 inet_csk_reqsk_queue_added(sk);
641}
642EXPORT_SYMBOL_GPL(inet_csk_reqsk_queue_hash_add);
643
644
645
646
647
648
649
650
651
652struct sock *inet_csk_clone_lock(const struct sock *sk,
653 const struct request_sock *req,
654 const gfp_t priority)
655{
656 struct sock *newsk = sk_clone_lock(sk, priority);
657
658 if (newsk) {
659 struct inet_connection_sock *newicsk = inet_csk(newsk);
660
661 newsk->sk_state = TCP_SYN_RECV;
662 newicsk->icsk_bind_hash = NULL;
663
664 inet_sk(newsk)->inet_dport = inet_rsk(req)->ir_rmt_port;
665 inet_sk(newsk)->inet_num = inet_rsk(req)->ir_num;
666 inet_sk(newsk)->inet_sport = htons(inet_rsk(req)->ir_num);
667 newsk->sk_write_space = sk_stream_write_space;
668
669
670 sock_reset_flag(newsk, SOCK_RCU_FREE);
671
672 newsk->sk_mark = inet_rsk(req)->ir_mark;
673 atomic64_set(&newsk->sk_cookie,
674 atomic64_read(&inet_rsk(req)->ir_cookie));
675
676 newicsk->icsk_retransmits = 0;
677 newicsk->icsk_backoff = 0;
678 newicsk->icsk_probes_out = 0;
679
680
681 memset(&newicsk->icsk_accept_queue, 0, sizeof(newicsk->icsk_accept_queue));
682
683 security_inet_csk_clone(newsk, req);
684 }
685 return newsk;
686}
687EXPORT_SYMBOL_GPL(inet_csk_clone_lock);
688
689
690
691
692
693
694
695void inet_csk_destroy_sock(struct sock *sk)
696{
697 WARN_ON(sk->sk_state != TCP_CLOSE);
698 WARN_ON(!sock_flag(sk, SOCK_DEAD));
699
700
701 WARN_ON(!sk_unhashed(sk));
702
703
704 WARN_ON(inet_sk(sk)->inet_num && !inet_csk(sk)->icsk_bind_hash);
705
706 sk->sk_prot->destroy(sk);
707
708 sk_stream_kill_queues(sk);
709
710 xfrm_sk_free_policy(sk);
711
712 sk_refcnt_debug_release(sk);
713
714 local_bh_disable();
715 percpu_counter_dec(sk->sk_prot->orphan_count);
716 local_bh_enable();
717 sock_put(sk);
718}
719EXPORT_SYMBOL(inet_csk_destroy_sock);
720
721
722
723
724void inet_csk_prepare_forced_close(struct sock *sk)
725 __releases(&sk->sk_lock.slock)
726{
727
728 bh_unlock_sock(sk);
729 sock_put(sk);
730
731
732 sock_set_flag(sk, SOCK_DEAD);
733 percpu_counter_inc(sk->sk_prot->orphan_count);
734 inet_sk(sk)->inet_num = 0;
735}
736EXPORT_SYMBOL(inet_csk_prepare_forced_close);
737
738int inet_csk_listen_start(struct sock *sk, int backlog)
739{
740 struct inet_connection_sock *icsk = inet_csk(sk);
741 struct inet_sock *inet = inet_sk(sk);
742 int err = -EADDRINUSE;
743
744 reqsk_queue_alloc(&icsk->icsk_accept_queue);
745
746 sk->sk_max_ack_backlog = backlog;
747 sk->sk_ack_backlog = 0;
748 inet_csk_delack_init(sk);
749
750
751
752
753
754
755 sk_state_store(sk, TCP_LISTEN);
756 if (!sk->sk_prot->get_port(sk, inet->inet_num)) {
757 inet->inet_sport = htons(inet->inet_num);
758
759 sk_dst_reset(sk);
760 err = sk->sk_prot->hash(sk);
761
762 if (likely(!err))
763 return 0;
764 }
765
766 sk->sk_state = TCP_CLOSE;
767 return err;
768}
769EXPORT_SYMBOL_GPL(inet_csk_listen_start);
770
771static void inet_child_forget(struct sock *sk, struct request_sock *req,
772 struct sock *child)
773{
774 sk->sk_prot->disconnect(child, O_NONBLOCK);
775
776 sock_orphan(child);
777
778 percpu_counter_inc(sk->sk_prot->orphan_count);
779
780 if (sk->sk_protocol == IPPROTO_TCP && tcp_rsk(req)->tfo_listener) {
781 BUG_ON(tcp_sk(child)->fastopen_rsk != req);
782 BUG_ON(sk != req->rsk_listener);
783
784
785
786
787
788
789
790 tcp_sk(child)->fastopen_rsk = NULL;
791 }
792 inet_csk_destroy_sock(child);
793 reqsk_put(req);
794}
795
796struct sock *inet_csk_reqsk_queue_add(struct sock *sk,
797 struct request_sock *req,
798 struct sock *child)
799{
800 struct request_sock_queue *queue = &inet_csk(sk)->icsk_accept_queue;
801
802 spin_lock(&queue->rskq_lock);
803 if (unlikely(sk->sk_state != TCP_LISTEN)) {
804 inet_child_forget(sk, req, child);
805 child = NULL;
806 } else {
807 req->sk = child;
808 req->dl_next = NULL;
809 if (queue->rskq_accept_head == NULL)
810 queue->rskq_accept_head = req;
811 else
812 queue->rskq_accept_tail->dl_next = req;
813 queue->rskq_accept_tail = req;
814 sk_acceptq_added(sk);
815 }
816 spin_unlock(&queue->rskq_lock);
817 return child;
818}
819EXPORT_SYMBOL(inet_csk_reqsk_queue_add);
820
821struct sock *inet_csk_complete_hashdance(struct sock *sk, struct sock *child,
822 struct request_sock *req, bool own_req)
823{
824 if (own_req) {
825 inet_csk_reqsk_queue_drop(sk, req);
826 reqsk_queue_removed(&inet_csk(sk)->icsk_accept_queue, req);
827 if (inet_csk_reqsk_queue_add(sk, req, child))
828 return child;
829 }
830
831 bh_unlock_sock(child);
832 sock_put(child);
833 return NULL;
834}
835EXPORT_SYMBOL(inet_csk_complete_hashdance);
836
837
838
839
840
841void inet_csk_listen_stop(struct sock *sk)
842{
843 struct inet_connection_sock *icsk = inet_csk(sk);
844 struct request_sock_queue *queue = &icsk->icsk_accept_queue;
845 struct request_sock *next, *req;
846
847
848
849
850
851
852
853
854
855 while ((req = reqsk_queue_remove(queue, sk)) != NULL) {
856 struct sock *child = req->sk;
857
858 local_bh_disable();
859 bh_lock_sock(child);
860 WARN_ON(sock_owned_by_user(child));
861 sock_hold(child);
862
863 inet_child_forget(sk, req, child);
864 bh_unlock_sock(child);
865 local_bh_enable();
866 sock_put(child);
867
868 cond_resched();
869 }
870 if (queue->fastopenq.rskq_rst_head) {
871
872 spin_lock_bh(&queue->fastopenq.lock);
873 req = queue->fastopenq.rskq_rst_head;
874 queue->fastopenq.rskq_rst_head = NULL;
875 spin_unlock_bh(&queue->fastopenq.lock);
876 while (req != NULL) {
877 next = req->dl_next;
878 reqsk_put(req);
879 req = next;
880 }
881 }
882 WARN_ON_ONCE(sk->sk_ack_backlog);
883}
884EXPORT_SYMBOL_GPL(inet_csk_listen_stop);
885
886void inet_csk_addr2sockaddr(struct sock *sk, struct sockaddr *uaddr)
887{
888 struct sockaddr_in *sin = (struct sockaddr_in *)uaddr;
889 const struct inet_sock *inet = inet_sk(sk);
890
891 sin->sin_family = AF_INET;
892 sin->sin_addr.s_addr = inet->inet_daddr;
893 sin->sin_port = inet->inet_dport;
894}
895EXPORT_SYMBOL_GPL(inet_csk_addr2sockaddr);
896
897#ifdef CONFIG_COMPAT
898int inet_csk_compat_getsockopt(struct sock *sk, int level, int optname,
899 char __user *optval, int __user *optlen)
900{
901 const struct inet_connection_sock *icsk = inet_csk(sk);
902
903 if (icsk->icsk_af_ops->compat_getsockopt)
904 return icsk->icsk_af_ops->compat_getsockopt(sk, level, optname,
905 optval, optlen);
906 return icsk->icsk_af_ops->getsockopt(sk, level, optname,
907 optval, optlen);
908}
909EXPORT_SYMBOL_GPL(inet_csk_compat_getsockopt);
910
911int inet_csk_compat_setsockopt(struct sock *sk, int level, int optname,
912 char __user *optval, unsigned int optlen)
913{
914 const struct inet_connection_sock *icsk = inet_csk(sk);
915
916 if (icsk->icsk_af_ops->compat_setsockopt)
917 return icsk->icsk_af_ops->compat_setsockopt(sk, level, optname,
918 optval, optlen);
919 return icsk->icsk_af_ops->setsockopt(sk, level, optname,
920 optval, optlen);
921}
922EXPORT_SYMBOL_GPL(inet_csk_compat_setsockopt);
923#endif
924
925static struct dst_entry *inet_csk_rebuild_route(struct sock *sk, struct flowi *fl)
926{
927 const struct inet_sock *inet = inet_sk(sk);
928 const struct ip_options_rcu *inet_opt;
929 __be32 daddr = inet->inet_daddr;
930 struct flowi4 *fl4;
931 struct rtable *rt;
932
933 rcu_read_lock();
934 inet_opt = rcu_dereference(inet->inet_opt);
935 if (inet_opt && inet_opt->opt.srr)
936 daddr = inet_opt->opt.faddr;
937 fl4 = &fl->u.ip4;
938 rt = ip_route_output_ports(sock_net(sk), fl4, sk, daddr,
939 inet->inet_saddr, inet->inet_dport,
940 inet->inet_sport, sk->sk_protocol,
941 RT_CONN_FLAGS(sk), sk->sk_bound_dev_if);
942 if (IS_ERR(rt))
943 rt = NULL;
944 if (rt)
945 sk_setup_caps(sk, &rt->dst);
946 rcu_read_unlock();
947
948 return &rt->dst;
949}
950
951struct dst_entry *inet_csk_update_pmtu(struct sock *sk, u32 mtu)
952{
953 struct dst_entry *dst = __sk_dst_check(sk, 0);
954 struct inet_sock *inet = inet_sk(sk);
955
956 if (!dst) {
957 dst = inet_csk_rebuild_route(sk, &inet->cork.fl);
958 if (!dst)
959 goto out;
960 }
961 dst->ops->update_pmtu(dst, sk, NULL, mtu);
962
963 dst = __sk_dst_check(sk, 0);
964 if (!dst)
965 dst = inet_csk_rebuild_route(sk, &inet->cork.fl);
966out:
967 return dst;
968}
969EXPORT_SYMBOL_GPL(inet_csk_update_pmtu);
970