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.
6 * Support for INET connection oriented protocols.
8 * Authors: See the TCP sources
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.
16 #include <linux/module.h>
17 #include <linux/jhash.h>
19 #include <net/inet_connection_sock.h>
20 #include <net/inet_hashtables.h>
21 #include <net/inet_timewait_sock.h>
23 #include <net/route.h>
24 #include <net/tcp_states.h>
28 const char inet_csk_timer_bug_msg
[] = "inet_csk BUG: unknown timer value\n";
29 EXPORT_SYMBOL(inet_csk_timer_bug_msg
);
32 void inet_get_local_port_range(struct net
*net
, int *low
, int *high
)
37 seq
= read_seqbegin(&net
->ipv4
.ip_local_ports
.lock
);
39 *low
= net
->ipv4
.ip_local_ports
.range
[0];
40 *high
= net
->ipv4
.ip_local_ports
.range
[1];
41 } while (read_seqretry(&net
->ipv4
.ip_local_ports
.lock
, seq
));
43 EXPORT_SYMBOL(inet_get_local_port_range
);
45 int inet_csk_bind_conflict(const struct sock
*sk
,
46 const struct inet_bind_bucket
*tb
, bool relax
)
49 int reuse
= sk
->sk_reuse
;
50 int reuseport
= sk
->sk_reuseport
;
51 kuid_t uid
= sock_i_uid((struct sock
*)sk
);
54 * Unlike other sk lookup places we do not check
55 * for sk_net here, since _all_ the socks listed
56 * in tb->owners list belong to the same net - the
57 * one this bucket belongs to.
60 sk_for_each_bound(sk2
, &tb
->owners
) {
62 !inet_v6_ipv6only(sk2
) &&
63 (!sk
->sk_bound_dev_if
||
64 !sk2
->sk_bound_dev_if
||
65 sk
->sk_bound_dev_if
== sk2
->sk_bound_dev_if
)) {
66 if ((!reuse
|| !sk2
->sk_reuse
||
67 sk2
->sk_state
== TCP_LISTEN
) &&
68 (!reuseport
|| !sk2
->sk_reuseport
||
69 (sk2
->sk_state
!= TCP_TIME_WAIT
&&
70 !uid_eq(uid
, sock_i_uid(sk2
))))) {
72 if (!sk2
->sk_rcv_saddr
|| !sk
->sk_rcv_saddr
||
73 sk2
->sk_rcv_saddr
== sk
->sk_rcv_saddr
)
76 if (!relax
&& reuse
&& sk2
->sk_reuse
&&
77 sk2
->sk_state
!= TCP_LISTEN
) {
79 if (!sk2
->sk_rcv_saddr
|| !sk
->sk_rcv_saddr
||
80 sk2
->sk_rcv_saddr
== sk
->sk_rcv_saddr
)
87 EXPORT_SYMBOL_GPL(inet_csk_bind_conflict
);
89 /* Obtain a reference to a local port for the given sock,
90 * if snum is zero it means select any available local port.
92 int inet_csk_get_port(struct sock
*sk
, unsigned short snum
)
94 struct inet_hashinfo
*hashinfo
= sk
->sk_prot
->h
.hashinfo
;
95 struct inet_bind_hashbucket
*head
;
96 struct inet_bind_bucket
*tb
;
97 int ret
, attempts
= 5;
98 struct net
*net
= sock_net(sk
);
99 int smallest_size
= -1, smallest_rover
;
100 kuid_t uid
= sock_i_uid(sk
);
104 int remaining
, rover
, low
, high
;
107 inet_get_local_port_range(net
, &low
, &high
);
108 remaining
= (high
- low
) + 1;
109 smallest_rover
= rover
= prandom_u32() % remaining
+ low
;
113 if (inet_is_local_reserved_port(net
, rover
))
115 head
= &hashinfo
->bhash
[inet_bhashfn(net
, rover
,
116 hashinfo
->bhash_size
)];
117 spin_lock(&head
->lock
);
118 inet_bind_bucket_for_each(tb
, &head
->chain
)
119 if (net_eq(ib_net(tb
), net
) && tb
->port
== rover
) {
120 if (((tb
->fastreuse
> 0 &&
122 sk
->sk_state
!= TCP_LISTEN
) ||
123 (tb
->fastreuseport
> 0 &&
125 uid_eq(tb
->fastuid
, uid
))) &&
126 (tb
->num_owners
< smallest_size
|| smallest_size
== -1)) {
127 smallest_size
= tb
->num_owners
;
128 smallest_rover
= rover
;
129 if (atomic_read(&hashinfo
->bsockets
) > (high
- low
) + 1 &&
130 !inet_csk(sk
)->icsk_af_ops
->bind_conflict(sk
, tb
, false)) {
131 snum
= smallest_rover
;
135 if (!inet_csk(sk
)->icsk_af_ops
->bind_conflict(sk
, tb
, false)) {
143 spin_unlock(&head
->lock
);
147 } while (--remaining
> 0);
149 /* Exhausted local port range during search? It is not
150 * possible for us to be holding one of the bind hash
151 * locks if this test triggers, because if 'remaining'
152 * drops to zero, we broke out of the do/while loop at
153 * the top level, not from the 'break;' statement.
156 if (remaining
<= 0) {
157 if (smallest_size
!= -1) {
158 snum
= smallest_rover
;
163 /* OK, here is the one we will use. HEAD is
164 * non-NULL and we hold it's mutex.
169 head
= &hashinfo
->bhash
[inet_bhashfn(net
, snum
,
170 hashinfo
->bhash_size
)];
171 spin_lock(&head
->lock
);
172 inet_bind_bucket_for_each(tb
, &head
->chain
)
173 if (net_eq(ib_net(tb
), net
) && tb
->port
== snum
)
179 if (!hlist_empty(&tb
->owners
)) {
180 if (sk
->sk_reuse
== SK_FORCE_REUSE
)
183 if (((tb
->fastreuse
> 0 &&
184 sk
->sk_reuse
&& sk
->sk_state
!= TCP_LISTEN
) ||
185 (tb
->fastreuseport
> 0 &&
186 sk
->sk_reuseport
&& uid_eq(tb
->fastuid
, uid
))) &&
187 smallest_size
== -1) {
191 if (inet_csk(sk
)->icsk_af_ops
->bind_conflict(sk
, tb
, true)) {
192 if (((sk
->sk_reuse
&& sk
->sk_state
!= TCP_LISTEN
) ||
193 (tb
->fastreuseport
> 0 &&
194 sk
->sk_reuseport
&& uid_eq(tb
->fastuid
, uid
))) &&
195 smallest_size
!= -1 && --attempts
>= 0) {
196 spin_unlock(&head
->lock
);
206 if (!tb
&& (tb
= inet_bind_bucket_create(hashinfo
->bind_bucket_cachep
,
207 net
, head
, snum
)) == NULL
)
209 if (hlist_empty(&tb
->owners
)) {
210 if (sk
->sk_reuse
&& sk
->sk_state
!= TCP_LISTEN
)
214 if (sk
->sk_reuseport
) {
215 tb
->fastreuseport
= 1;
218 tb
->fastreuseport
= 0;
221 (!sk
->sk_reuse
|| sk
->sk_state
== TCP_LISTEN
))
223 if (tb
->fastreuseport
&&
224 (!sk
->sk_reuseport
|| !uid_eq(tb
->fastuid
, uid
)))
225 tb
->fastreuseport
= 0;
228 if (!inet_csk(sk
)->icsk_bind_hash
)
229 inet_bind_hash(sk
, tb
, snum
);
230 WARN_ON(inet_csk(sk
)->icsk_bind_hash
!= tb
);
234 spin_unlock(&head
->lock
);
239 EXPORT_SYMBOL_GPL(inet_csk_get_port
);
242 * Wait for an incoming connection, avoid race conditions. This must be called
243 * with the socket locked.
245 static int inet_csk_wait_for_connect(struct sock
*sk
, long timeo
)
247 struct inet_connection_sock
*icsk
= inet_csk(sk
);
252 * True wake-one mechanism for incoming connections: only
253 * one process gets woken up, not the 'whole herd'.
254 * Since we do not 'race & poll' for established sockets
255 * anymore, the common case will execute the loop only once.
257 * Subtle issue: "add_wait_queue_exclusive()" will be added
258 * after any current non-exclusive waiters, and we know that
259 * it will always _stay_ after any new non-exclusive waiters
260 * because all non-exclusive waiters are added at the
261 * beginning of the wait-queue. As such, it's ok to "drop"
262 * our exclusiveness temporarily when we get woken up without
263 * having to remove and re-insert us on the wait queue.
266 prepare_to_wait_exclusive(sk_sleep(sk
), &wait
,
269 if (reqsk_queue_empty(&icsk
->icsk_accept_queue
))
270 timeo
= schedule_timeout(timeo
);
271 sched_annotate_sleep();
274 if (!reqsk_queue_empty(&icsk
->icsk_accept_queue
))
277 if (sk
->sk_state
!= TCP_LISTEN
)
279 err
= sock_intr_errno(timeo
);
280 if (signal_pending(current
))
286 finish_wait(sk_sleep(sk
), &wait
);
291 * This will accept the next outstanding connection.
293 struct sock
*inet_csk_accept(struct sock
*sk
, int flags
, int *err
)
295 struct inet_connection_sock
*icsk
= inet_csk(sk
);
296 struct request_sock_queue
*queue
= &icsk
->icsk_accept_queue
;
298 struct request_sock
*req
;
303 /* We need to make sure that this socket is listening,
304 * and that it has something pending.
307 if (sk
->sk_state
!= TCP_LISTEN
)
310 /* Find already established connection */
311 if (reqsk_queue_empty(queue
)) {
312 long timeo
= sock_rcvtimeo(sk
, flags
& O_NONBLOCK
);
314 /* If this is a non blocking socket don't sleep */
319 error
= inet_csk_wait_for_connect(sk
, timeo
);
323 req
= reqsk_queue_remove(queue
);
326 sk_acceptq_removed(sk
);
327 if (sk
->sk_protocol
== IPPROTO_TCP
&& queue
->fastopenq
!= NULL
) {
328 spin_lock_bh(&queue
->fastopenq
->lock
);
329 if (tcp_rsk(req
)->listener
) {
330 /* We are still waiting for the final ACK from 3WHS
331 * so can't free req now. Instead, we set req->sk to
332 * NULL to signify that the child socket is taken
333 * so reqsk_fastopen_remove() will free the req
334 * when 3WHS finishes (or is aborted).
339 spin_unlock_bh(&queue
->fastopenq
->lock
);
352 EXPORT_SYMBOL(inet_csk_accept
);
355 * Using different timers for retransmit, delayed acks and probes
356 * We may wish use just one timer maintaining a list of expire jiffies
359 void inet_csk_init_xmit_timers(struct sock
*sk
,
360 void (*retransmit_handler
)(unsigned long),
361 void (*delack_handler
)(unsigned long),
362 void (*keepalive_handler
)(unsigned long))
364 struct inet_connection_sock
*icsk
= inet_csk(sk
);
366 setup_timer(&icsk
->icsk_retransmit_timer
, retransmit_handler
,
368 setup_timer(&icsk
->icsk_delack_timer
, delack_handler
,
370 setup_timer(&sk
->sk_timer
, keepalive_handler
, (unsigned long)sk
);
371 icsk
->icsk_pending
= icsk
->icsk_ack
.pending
= 0;
373 EXPORT_SYMBOL(inet_csk_init_xmit_timers
);
375 void inet_csk_clear_xmit_timers(struct sock
*sk
)
377 struct inet_connection_sock
*icsk
= inet_csk(sk
);
379 icsk
->icsk_pending
= icsk
->icsk_ack
.pending
= icsk
->icsk_ack
.blocked
= 0;
381 sk_stop_timer(sk
, &icsk
->icsk_retransmit_timer
);
382 sk_stop_timer(sk
, &icsk
->icsk_delack_timer
);
383 sk_stop_timer(sk
, &sk
->sk_timer
);
385 EXPORT_SYMBOL(inet_csk_clear_xmit_timers
);
387 void inet_csk_delete_keepalive_timer(struct sock
*sk
)
389 sk_stop_timer(sk
, &sk
->sk_timer
);
391 EXPORT_SYMBOL(inet_csk_delete_keepalive_timer
);
393 void inet_csk_reset_keepalive_timer(struct sock
*sk
, unsigned long len
)
395 sk_reset_timer(sk
, &sk
->sk_timer
, jiffies
+ len
);
397 EXPORT_SYMBOL(inet_csk_reset_keepalive_timer
);
399 struct dst_entry
*inet_csk_route_req(struct sock
*sk
,
401 const struct request_sock
*req
)
404 const struct inet_request_sock
*ireq
= inet_rsk(req
);
405 struct ip_options_rcu
*opt
= inet_rsk(req
)->opt
;
406 struct net
*net
= sock_net(sk
);
407 int flags
= inet_sk_flowi_flags(sk
);
409 flowi4_init_output(fl4
, sk
->sk_bound_dev_if
, ireq
->ir_mark
,
410 RT_CONN_FLAGS(sk
), RT_SCOPE_UNIVERSE
,
413 (opt
&& opt
->opt
.srr
) ? opt
->opt
.faddr
: ireq
->ir_rmt_addr
,
414 ireq
->ir_loc_addr
, ireq
->ir_rmt_port
, inet_sk(sk
)->inet_sport
);
415 security_req_classify_flow(req
, flowi4_to_flowi(fl4
));
416 rt
= ip_route_output_flow(net
, fl4
, sk
);
419 if (opt
&& opt
->opt
.is_strictroute
&& rt
->rt_uses_gateway
)
426 IP_INC_STATS_BH(net
, IPSTATS_MIB_OUTNOROUTES
);
429 EXPORT_SYMBOL_GPL(inet_csk_route_req
);
431 struct dst_entry
*inet_csk_route_child_sock(struct sock
*sk
,
433 const struct request_sock
*req
)
435 const struct inet_request_sock
*ireq
= inet_rsk(req
);
436 struct inet_sock
*newinet
= inet_sk(newsk
);
437 struct ip_options_rcu
*opt
;
438 struct net
*net
= sock_net(sk
);
442 fl4
= &newinet
->cork
.fl
.u
.ip4
;
445 opt
= rcu_dereference(newinet
->inet_opt
);
446 flowi4_init_output(fl4
, sk
->sk_bound_dev_if
, inet_rsk(req
)->ir_mark
,
447 RT_CONN_FLAGS(sk
), RT_SCOPE_UNIVERSE
,
448 sk
->sk_protocol
, inet_sk_flowi_flags(sk
),
449 (opt
&& opt
->opt
.srr
) ? opt
->opt
.faddr
: ireq
->ir_rmt_addr
,
450 ireq
->ir_loc_addr
, ireq
->ir_rmt_port
, inet_sk(sk
)->inet_sport
);
451 security_req_classify_flow(req
, flowi4_to_flowi(fl4
));
452 rt
= ip_route_output_flow(net
, fl4
, sk
);
455 if (opt
&& opt
->opt
.is_strictroute
&& rt
->rt_uses_gateway
)
464 IP_INC_STATS_BH(net
, IPSTATS_MIB_OUTNOROUTES
);
467 EXPORT_SYMBOL_GPL(inet_csk_route_child_sock
);
469 static inline u32
inet_synq_hash(const __be32 raddr
, const __be16 rport
,
470 const u32 rnd
, const u32 synq_hsize
)
472 return jhash_2words((__force u32
)raddr
, (__force u32
)rport
, rnd
) & (synq_hsize
- 1);
475 #if IS_ENABLED(CONFIG_IPV6)
476 #define AF_INET_FAMILY(fam) ((fam) == AF_INET)
478 #define AF_INET_FAMILY(fam) 1
481 struct request_sock
*inet_csk_search_req(const struct sock
*sk
,
482 struct request_sock
***prevp
,
483 const __be16 rport
, const __be32 raddr
,
486 const struct inet_connection_sock
*icsk
= inet_csk(sk
);
487 struct listen_sock
*lopt
= icsk
->icsk_accept_queue
.listen_opt
;
488 struct request_sock
*req
, **prev
;
490 for (prev
= &lopt
->syn_table
[inet_synq_hash(raddr
, rport
, lopt
->hash_rnd
,
491 lopt
->nr_table_entries
)];
492 (req
= *prev
) != NULL
;
493 prev
= &req
->dl_next
) {
494 const struct inet_request_sock
*ireq
= inet_rsk(req
);
496 if (ireq
->ir_rmt_port
== rport
&&
497 ireq
->ir_rmt_addr
== raddr
&&
498 ireq
->ir_loc_addr
== laddr
&&
499 AF_INET_FAMILY(req
->rsk_ops
->family
)) {
508 EXPORT_SYMBOL_GPL(inet_csk_search_req
);
510 void inet_csk_reqsk_queue_hash_add(struct sock
*sk
, struct request_sock
*req
,
511 unsigned long timeout
)
513 struct inet_connection_sock
*icsk
= inet_csk(sk
);
514 struct listen_sock
*lopt
= icsk
->icsk_accept_queue
.listen_opt
;
515 const u32 h
= inet_synq_hash(inet_rsk(req
)->ir_rmt_addr
,
516 inet_rsk(req
)->ir_rmt_port
,
517 lopt
->hash_rnd
, lopt
->nr_table_entries
);
519 reqsk_queue_hash_req(&icsk
->icsk_accept_queue
, h
, req
, timeout
);
520 inet_csk_reqsk_queue_added(sk
, timeout
);
522 EXPORT_SYMBOL_GPL(inet_csk_reqsk_queue_hash_add
);
524 /* Only thing we need from tcp.h */
525 extern int sysctl_tcp_synack_retries
;
528 /* Decide when to expire the request and when to resend SYN-ACK */
529 static inline void syn_ack_recalc(struct request_sock
*req
, const int thresh
,
530 const int max_retries
,
531 const u8 rskq_defer_accept
,
532 int *expire
, int *resend
)
534 if (!rskq_defer_accept
) {
535 *expire
= req
->num_timeout
>= thresh
;
539 *expire
= req
->num_timeout
>= thresh
&&
540 (!inet_rsk(req
)->acked
|| req
->num_timeout
>= max_retries
);
542 * Do not resend while waiting for data after ACK,
543 * start to resend on end of deferring period to give
544 * last chance for data or ACK to create established socket.
546 *resend
= !inet_rsk(req
)->acked
||
547 req
->num_timeout
>= rskq_defer_accept
- 1;
550 int inet_rtx_syn_ack(struct sock
*parent
, struct request_sock
*req
)
552 int err
= req
->rsk_ops
->rtx_syn_ack(parent
, req
);
558 EXPORT_SYMBOL(inet_rtx_syn_ack
);
560 void inet_csk_reqsk_queue_prune(struct sock
*parent
,
561 const unsigned long interval
,
562 const unsigned long timeout
,
563 const unsigned long max_rto
)
565 struct inet_connection_sock
*icsk
= inet_csk(parent
);
566 struct request_sock_queue
*queue
= &icsk
->icsk_accept_queue
;
567 struct listen_sock
*lopt
= queue
->listen_opt
;
568 int max_retries
= icsk
->icsk_syn_retries
? : sysctl_tcp_synack_retries
;
569 int thresh
= max_retries
;
570 unsigned long now
= jiffies
;
571 struct request_sock
**reqp
, *req
;
574 if (lopt
== NULL
|| lopt
->qlen
== 0)
577 /* Normally all the openreqs are young and become mature
578 * (i.e. converted to established socket) for first timeout.
579 * If synack was not acknowledged for 1 second, it means
580 * one of the following things: synack was lost, ack was lost,
581 * rtt is high or nobody planned to ack (i.e. synflood).
582 * When server is a bit loaded, queue is populated with old
583 * open requests, reducing effective size of queue.
584 * When server is well loaded, queue size reduces to zero
585 * after several minutes of work. It is not synflood,
586 * it is normal operation. The solution is pruning
587 * too old entries overriding normal timeout, when
588 * situation becomes dangerous.
590 * Essentially, we reserve half of room for young
591 * embrions; and abort old ones without pity, if old
592 * ones are about to clog our table.
594 if (lopt
->qlen
>>(lopt
->max_qlen_log
-1)) {
595 int young
= (lopt
->qlen_young
<<1);
598 if (lopt
->qlen
< young
)
605 if (queue
->rskq_defer_accept
)
606 max_retries
= queue
->rskq_defer_accept
;
608 budget
= 2 * (lopt
->nr_table_entries
/ (timeout
/ interval
));
609 i
= lopt
->clock_hand
;
612 reqp
=&lopt
->syn_table
[i
];
613 while ((req
= *reqp
) != NULL
) {
614 if (time_after_eq(now
, req
->expires
)) {
615 int expire
= 0, resend
= 0;
617 syn_ack_recalc(req
, thresh
, max_retries
,
618 queue
->rskq_defer_accept
,
620 req
->rsk_ops
->syn_ack_timeout(parent
, req
);
623 !inet_rtx_syn_ack(parent
, req
) ||
624 inet_rsk(req
)->acked
)) {
627 if (req
->num_timeout
++ == 0)
629 timeo
= min(timeout
<< req
->num_timeout
,
631 req
->expires
= now
+ timeo
;
632 reqp
= &req
->dl_next
;
636 /* Drop this request */
637 inet_csk_reqsk_queue_unlink(parent
, req
, reqp
);
638 reqsk_queue_removed(queue
, req
);
642 reqp
= &req
->dl_next
;
645 i
= (i
+ 1) & (lopt
->nr_table_entries
- 1);
647 } while (--budget
> 0);
649 lopt
->clock_hand
= i
;
652 inet_csk_reset_keepalive_timer(parent
, interval
);
654 EXPORT_SYMBOL_GPL(inet_csk_reqsk_queue_prune
);
657 * inet_csk_clone_lock - clone an inet socket, and lock its clone
658 * @sk: the socket to clone
660 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
662 * Caller must unlock socket even in error path (bh_unlock_sock(newsk))
664 struct sock
*inet_csk_clone_lock(const struct sock
*sk
,
665 const struct request_sock
*req
,
666 const gfp_t priority
)
668 struct sock
*newsk
= sk_clone_lock(sk
, priority
);
671 struct inet_connection_sock
*newicsk
= inet_csk(newsk
);
673 newsk
->sk_state
= TCP_SYN_RECV
;
674 newicsk
->icsk_bind_hash
= NULL
;
676 inet_sk(newsk
)->inet_dport
= inet_rsk(req
)->ir_rmt_port
;
677 inet_sk(newsk
)->inet_num
= inet_rsk(req
)->ir_num
;
678 inet_sk(newsk
)->inet_sport
= htons(inet_rsk(req
)->ir_num
);
679 newsk
->sk_write_space
= sk_stream_write_space
;
681 newsk
->sk_mark
= inet_rsk(req
)->ir_mark
;
683 newicsk
->icsk_retransmits
= 0;
684 newicsk
->icsk_backoff
= 0;
685 newicsk
->icsk_probes_out
= 0;
687 /* Deinitialize accept_queue to trap illegal accesses. */
688 memset(&newicsk
->icsk_accept_queue
, 0, sizeof(newicsk
->icsk_accept_queue
));
690 security_inet_csk_clone(newsk
, req
);
694 EXPORT_SYMBOL_GPL(inet_csk_clone_lock
);
697 * At this point, there should be no process reference to this
698 * socket, and thus no user references at all. Therefore we
699 * can assume the socket waitqueue is inactive and nobody will
700 * try to jump onto it.
702 void inet_csk_destroy_sock(struct sock
*sk
)
704 WARN_ON(sk
->sk_state
!= TCP_CLOSE
);
705 WARN_ON(!sock_flag(sk
, SOCK_DEAD
));
707 /* It cannot be in hash table! */
708 WARN_ON(!sk_unhashed(sk
));
710 /* If it has not 0 inet_sk(sk)->inet_num, it must be bound */
711 WARN_ON(inet_sk(sk
)->inet_num
&& !inet_csk(sk
)->icsk_bind_hash
);
713 sk
->sk_prot
->destroy(sk
);
715 sk_stream_kill_queues(sk
);
717 xfrm_sk_free_policy(sk
);
719 sk_refcnt_debug_release(sk
);
721 percpu_counter_dec(sk
->sk_prot
->orphan_count
);
724 EXPORT_SYMBOL(inet_csk_destroy_sock
);
726 /* This function allows to force a closure of a socket after the call to
727 * tcp/dccp_create_openreq_child().
729 void inet_csk_prepare_forced_close(struct sock
*sk
)
730 __releases(&sk
->sk_lock
.slock
)
732 /* sk_clone_lock locked the socket and set refcnt to 2 */
736 /* The below has to be done to allow calling inet_csk_destroy_sock */
737 sock_set_flag(sk
, SOCK_DEAD
);
738 percpu_counter_inc(sk
->sk_prot
->orphan_count
);
739 inet_sk(sk
)->inet_num
= 0;
741 EXPORT_SYMBOL(inet_csk_prepare_forced_close
);
743 int inet_csk_listen_start(struct sock
*sk
, const int nr_table_entries
)
745 struct inet_sock
*inet
= inet_sk(sk
);
746 struct inet_connection_sock
*icsk
= inet_csk(sk
);
747 int rc
= reqsk_queue_alloc(&icsk
->icsk_accept_queue
, nr_table_entries
);
752 sk
->sk_max_ack_backlog
= 0;
753 sk
->sk_ack_backlog
= 0;
754 inet_csk_delack_init(sk
);
756 /* There is race window here: we announce ourselves listening,
757 * but this transition is still not validated by get_port().
758 * It is OK, because this socket enters to hash table only
759 * after validation is complete.
761 sk
->sk_state
= TCP_LISTEN
;
762 if (!sk
->sk_prot
->get_port(sk
, inet
->inet_num
)) {
763 inet
->inet_sport
= htons(inet
->inet_num
);
766 sk
->sk_prot
->hash(sk
);
771 sk
->sk_state
= TCP_CLOSE
;
772 __reqsk_queue_destroy(&icsk
->icsk_accept_queue
);
775 EXPORT_SYMBOL_GPL(inet_csk_listen_start
);
778 * This routine closes sockets which have been at least partially
779 * opened, but not yet accepted.
781 void inet_csk_listen_stop(struct sock
*sk
)
783 struct inet_connection_sock
*icsk
= inet_csk(sk
);
784 struct request_sock_queue
*queue
= &icsk
->icsk_accept_queue
;
785 struct request_sock
*acc_req
;
786 struct request_sock
*req
;
788 inet_csk_delete_keepalive_timer(sk
);
790 /* make all the listen_opt local to us */
791 acc_req
= reqsk_queue_yank_acceptq(queue
);
793 /* Following specs, it would be better either to send FIN
794 * (and enter FIN-WAIT-1, it is normal close)
795 * or to send active reset (abort).
796 * Certainly, it is pretty dangerous while synflood, but it is
797 * bad justification for our negligence 8)
798 * To be honest, we are not able to make either
799 * of the variants now. --ANK
801 reqsk_queue_destroy(queue
);
803 while ((req
= acc_req
) != NULL
) {
804 struct sock
*child
= req
->sk
;
806 acc_req
= req
->dl_next
;
810 WARN_ON(sock_owned_by_user(child
));
813 sk
->sk_prot
->disconnect(child
, O_NONBLOCK
);
817 percpu_counter_inc(sk
->sk_prot
->orphan_count
);
819 if (sk
->sk_protocol
== IPPROTO_TCP
&& tcp_rsk(req
)->listener
) {
820 BUG_ON(tcp_sk(child
)->fastopen_rsk
!= req
);
821 BUG_ON(sk
!= tcp_rsk(req
)->listener
);
823 /* Paranoid, to prevent race condition if
824 * an inbound pkt destined for child is
825 * blocked by sock lock in tcp_v4_rcv().
826 * Also to satisfy an assertion in
827 * tcp_v4_destroy_sock().
829 tcp_sk(child
)->fastopen_rsk
= NULL
;
832 inet_csk_destroy_sock(child
);
834 bh_unlock_sock(child
);
838 sk_acceptq_removed(sk
);
841 if (queue
->fastopenq
!= NULL
) {
842 /* Free all the reqs queued in rskq_rst_head. */
843 spin_lock_bh(&queue
->fastopenq
->lock
);
844 acc_req
= queue
->fastopenq
->rskq_rst_head
;
845 queue
->fastopenq
->rskq_rst_head
= NULL
;
846 spin_unlock_bh(&queue
->fastopenq
->lock
);
847 while ((req
= acc_req
) != NULL
) {
848 acc_req
= req
->dl_next
;
852 WARN_ON(sk
->sk_ack_backlog
);
854 EXPORT_SYMBOL_GPL(inet_csk_listen_stop
);
856 void inet_csk_addr2sockaddr(struct sock
*sk
, struct sockaddr
*uaddr
)
858 struct sockaddr_in
*sin
= (struct sockaddr_in
*)uaddr
;
859 const struct inet_sock
*inet
= inet_sk(sk
);
861 sin
->sin_family
= AF_INET
;
862 sin
->sin_addr
.s_addr
= inet
->inet_daddr
;
863 sin
->sin_port
= inet
->inet_dport
;
865 EXPORT_SYMBOL_GPL(inet_csk_addr2sockaddr
);
868 int inet_csk_compat_getsockopt(struct sock
*sk
, int level
, int optname
,
869 char __user
*optval
, int __user
*optlen
)
871 const struct inet_connection_sock
*icsk
= inet_csk(sk
);
873 if (icsk
->icsk_af_ops
->compat_getsockopt
!= NULL
)
874 return icsk
->icsk_af_ops
->compat_getsockopt(sk
, level
, optname
,
876 return icsk
->icsk_af_ops
->getsockopt(sk
, level
, optname
,
879 EXPORT_SYMBOL_GPL(inet_csk_compat_getsockopt
);
881 int inet_csk_compat_setsockopt(struct sock
*sk
, int level
, int optname
,
882 char __user
*optval
, unsigned int optlen
)
884 const struct inet_connection_sock
*icsk
= inet_csk(sk
);
886 if (icsk
->icsk_af_ops
->compat_setsockopt
!= NULL
)
887 return icsk
->icsk_af_ops
->compat_setsockopt(sk
, level
, optname
,
889 return icsk
->icsk_af_ops
->setsockopt(sk
, level
, optname
,
892 EXPORT_SYMBOL_GPL(inet_csk_compat_setsockopt
);
895 static struct dst_entry
*inet_csk_rebuild_route(struct sock
*sk
, struct flowi
*fl
)
897 const struct inet_sock
*inet
= inet_sk(sk
);
898 const struct ip_options_rcu
*inet_opt
;
899 __be32 daddr
= inet
->inet_daddr
;
904 inet_opt
= rcu_dereference(inet
->inet_opt
);
905 if (inet_opt
&& inet_opt
->opt
.srr
)
906 daddr
= inet_opt
->opt
.faddr
;
908 rt
= ip_route_output_ports(sock_net(sk
), fl4
, sk
, daddr
,
909 inet
->inet_saddr
, inet
->inet_dport
,
910 inet
->inet_sport
, sk
->sk_protocol
,
911 RT_CONN_FLAGS(sk
), sk
->sk_bound_dev_if
);
915 sk_setup_caps(sk
, &rt
->dst
);
921 struct dst_entry
*inet_csk_update_pmtu(struct sock
*sk
, u32 mtu
)
923 struct dst_entry
*dst
= __sk_dst_check(sk
, 0);
924 struct inet_sock
*inet
= inet_sk(sk
);
927 dst
= inet_csk_rebuild_route(sk
, &inet
->cork
.fl
);
931 dst
->ops
->update_pmtu(dst
, sk
, NULL
, mtu
);
933 dst
= __sk_dst_check(sk
, 0);
935 dst
= inet_csk_rebuild_route(sk
, &inet
->cork
.fl
);
939 EXPORT_SYMBOL_GPL(inet_csk_update_pmtu
);