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 	/*
59 	 * Unlike other sk lookup places we do not check
60 	 * for sk_net here, since _all_ the socks listed
61 	 * in tb->owners list belong to the same net - the
62 	 * one this bucket belongs to.
63 	 */
64 
65 	sk_for_each_bound(sk2, node, &tb->owners) {
66 		if (sk != sk2 &&
67 		    !inet_v6_ipv6only(sk2) &&
68 		    (!sk->sk_bound_dev_if ||
69 		     !sk2->sk_bound_dev_if ||
70 		     sk->sk_bound_dev_if == sk2->sk_bound_dev_if)) {
71 			if (!reuse || !sk2->sk_reuse ||
72 			    sk2->sk_state == TCP_LISTEN) {
73 				const __be32 sk2_rcv_saddr = inet_rcv_saddr(sk2);
74 				if (!sk2_rcv_saddr || !sk_rcv_saddr ||
75 				    sk2_rcv_saddr == sk_rcv_saddr)
76 					break;
77 			}
78 		}
79 	}
80 	return node != NULL;
81 }
82 
83 EXPORT_SYMBOL_GPL(inet_csk_bind_conflict);
84 
85 /* Obtain a reference to a local port for the given sock,
86  * if snum is zero it means select any available local port.
87  */
88 int inet_csk_get_port(struct sock *sk, unsigned short snum)
89 {
90 	struct inet_hashinfo *hashinfo = sk->sk_prot->h.hashinfo;
91 	struct inet_bind_hashbucket *head;
92 	struct hlist_node *node;
93 	struct inet_bind_bucket *tb;
94 	int ret;
95 	struct net *net = sock_net(sk);
96 
97 	local_bh_disable();
98 	if (!snum) {
99 		int remaining, rover, low, high;
100 
101 		inet_get_local_port_range(&low, &high);
102 		remaining = (high - low) + 1;
103 		rover = net_random() % remaining + low;
104 
105 		do {
106 			head = &hashinfo->bhash[inet_bhashfn(rover, hashinfo->bhash_size)];
107 			spin_lock(&head->lock);
108 			inet_bind_bucket_for_each(tb, node, &head->chain)
109 				if (tb->ib_net == net && tb->port == rover)
110 					goto next;
111 			break;
112 		next:
113 			spin_unlock(&head->lock);
114 			if (++rover > high)
115 				rover = low;
116 		} while (--remaining > 0);
117 
118 		/* Exhausted local port range during search?  It is not
119 		 * possible for us to be holding one of the bind hash
120 		 * locks if this test triggers, because if 'remaining'
121 		 * drops to zero, we broke out of the do/while loop at
122 		 * the top level, not from the 'break;' statement.
123 		 */
124 		ret = 1;
125 		if (remaining <= 0)
126 			goto fail;
127 
128 		/* OK, here is the one we will use.  HEAD is
129 		 * non-NULL and we hold it's mutex.
130 		 */
131 		snum = rover;
132 	} else {
133 		head = &hashinfo->bhash[inet_bhashfn(snum, hashinfo->bhash_size)];
134 		spin_lock(&head->lock);
135 		inet_bind_bucket_for_each(tb, node, &head->chain)
136 			if (tb->ib_net == net && tb->port == snum)
137 				goto tb_found;
138 	}
139 	tb = NULL;
140 	goto tb_not_found;
141 tb_found:
142 	if (!hlist_empty(&tb->owners)) {
143 		if (tb->fastreuse > 0 &&
144 		    sk->sk_reuse && sk->sk_state != TCP_LISTEN) {
145 			goto success;
146 		} else {
147 			ret = 1;
148 			if (inet_csk(sk)->icsk_af_ops->bind_conflict(sk, tb))
149 				goto fail_unlock;
150 		}
151 	}
152 tb_not_found:
153 	ret = 1;
154 	if (!tb && (tb = inet_bind_bucket_create(hashinfo->bind_bucket_cachep,
155 					net, head, snum)) == NULL)
156 		goto fail_unlock;
157 	if (hlist_empty(&tb->owners)) {
158 		if (sk->sk_reuse && sk->sk_state != TCP_LISTEN)
159 			tb->fastreuse = 1;
160 		else
161 			tb->fastreuse = 0;
162 	} else if (tb->fastreuse &&
163 		   (!sk->sk_reuse || sk->sk_state == TCP_LISTEN))
164 		tb->fastreuse = 0;
165 success:
166 	if (!inet_csk(sk)->icsk_bind_hash)
167 		inet_bind_hash(sk, tb, snum);
168 	BUG_TRAP(inet_csk(sk)->icsk_bind_hash == tb);
169 	ret = 0;
170 
171 fail_unlock:
172 	spin_unlock(&head->lock);
173 fail:
174 	local_bh_enable();
175 	return ret;
176 }
177 
178 EXPORT_SYMBOL_GPL(inet_csk_get_port);
179 
180 /*
181  * Wait for an incoming connection, avoid race conditions. This must be called
182  * with the socket locked.
183  */
184 static int inet_csk_wait_for_connect(struct sock *sk, long timeo)
185 {
186 	struct inet_connection_sock *icsk = inet_csk(sk);
187 	DEFINE_WAIT(wait);
188 	int err;
189 
190 	/*
191 	 * True wake-one mechanism for incoming connections: only
192 	 * one process gets woken up, not the 'whole herd'.
193 	 * Since we do not 'race & poll' for established sockets
194 	 * anymore, the common case will execute the loop only once.
195 	 *
196 	 * Subtle issue: "add_wait_queue_exclusive()" will be added
197 	 * after any current non-exclusive waiters, and we know that
198 	 * it will always _stay_ after any new non-exclusive waiters
199 	 * because all non-exclusive waiters are added at the
200 	 * beginning of the wait-queue. As such, it's ok to "drop"
201 	 * our exclusiveness temporarily when we get woken up without
202 	 * having to remove and re-insert us on the wait queue.
203 	 */
204 	for (;;) {
205 		prepare_to_wait_exclusive(sk->sk_sleep, &wait,
206 					  TASK_INTERRUPTIBLE);
207 		release_sock(sk);
208 		if (reqsk_queue_empty(&icsk->icsk_accept_queue))
209 			timeo = schedule_timeout(timeo);
210 		lock_sock(sk);
211 		err = 0;
212 		if (!reqsk_queue_empty(&icsk->icsk_accept_queue))
213 			break;
214 		err = -EINVAL;
215 		if (sk->sk_state != TCP_LISTEN)
216 			break;
217 		err = sock_intr_errno(timeo);
218 		if (signal_pending(current))
219 			break;
220 		err = -EAGAIN;
221 		if (!timeo)
222 			break;
223 	}
224 	finish_wait(sk->sk_sleep, &wait);
225 	return err;
226 }
227 
228 /*
229  * This will accept the next outstanding connection.
230  */
231 struct sock *inet_csk_accept(struct sock *sk, int flags, int *err)
232 {
233 	struct inet_connection_sock *icsk = inet_csk(sk);
234 	struct sock *newsk;
235 	int error;
236 
237 	lock_sock(sk);
238 
239 	/* We need to make sure that this socket is listening,
240 	 * and that it has something pending.
241 	 */
242 	error = -EINVAL;
243 	if (sk->sk_state != TCP_LISTEN)
244 		goto out_err;
245 
246 	/* Find already established connection */
247 	if (reqsk_queue_empty(&icsk->icsk_accept_queue)) {
248 		long timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
249 
250 		/* If this is a non blocking socket don't sleep */
251 		error = -EAGAIN;
252 		if (!timeo)
253 			goto out_err;
254 
255 		error = inet_csk_wait_for_connect(sk, timeo);
256 		if (error)
257 			goto out_err;
258 	}
259 
260 	newsk = reqsk_queue_get_child(&icsk->icsk_accept_queue, sk);
261 	BUG_TRAP(newsk->sk_state != TCP_SYN_RECV);
262 out:
263 	release_sock(sk);
264 	return newsk;
265 out_err:
266 	newsk = NULL;
267 	*err = error;
268 	goto out;
269 }
270 
271 EXPORT_SYMBOL(inet_csk_accept);
272 
273 /*
274  * Using different timers for retransmit, delayed acks and probes
275  * We may wish use just one timer maintaining a list of expire jiffies
276  * to optimize.
277  */
278 void inet_csk_init_xmit_timers(struct sock *sk,
279 			       void (*retransmit_handler)(unsigned long),
280 			       void (*delack_handler)(unsigned long),
281 			       void (*keepalive_handler)(unsigned long))
282 {
283 	struct inet_connection_sock *icsk = inet_csk(sk);
284 
285 	setup_timer(&icsk->icsk_retransmit_timer, retransmit_handler,
286 			(unsigned long)sk);
287 	setup_timer(&icsk->icsk_delack_timer, delack_handler,
288 			(unsigned long)sk);
289 	setup_timer(&sk->sk_timer, keepalive_handler, (unsigned long)sk);
290 	icsk->icsk_pending = icsk->icsk_ack.pending = 0;
291 }
292 
293 EXPORT_SYMBOL(inet_csk_init_xmit_timers);
294 
295 void inet_csk_clear_xmit_timers(struct sock *sk)
296 {
297 	struct inet_connection_sock *icsk = inet_csk(sk);
298 
299 	icsk->icsk_pending = icsk->icsk_ack.pending = icsk->icsk_ack.blocked = 0;
300 
301 	sk_stop_timer(sk, &icsk->icsk_retransmit_timer);
302 	sk_stop_timer(sk, &icsk->icsk_delack_timer);
303 	sk_stop_timer(sk, &sk->sk_timer);
304 }
305 
306 EXPORT_SYMBOL(inet_csk_clear_xmit_timers);
307 
308 void inet_csk_delete_keepalive_timer(struct sock *sk)
309 {
310 	sk_stop_timer(sk, &sk->sk_timer);
311 }
312 
313 EXPORT_SYMBOL(inet_csk_delete_keepalive_timer);
314 
315 void inet_csk_reset_keepalive_timer(struct sock *sk, unsigned long len)
316 {
317 	sk_reset_timer(sk, &sk->sk_timer, jiffies + len);
318 }
319 
320 EXPORT_SYMBOL(inet_csk_reset_keepalive_timer);
321 
322 struct dst_entry* inet_csk_route_req(struct sock *sk,
323 				     const struct request_sock *req)
324 {
325 	struct rtable *rt;
326 	const struct inet_request_sock *ireq = inet_rsk(req);
327 	struct ip_options *opt = inet_rsk(req)->opt;
328 	struct flowi fl = { .oif = sk->sk_bound_dev_if,
329 			    .nl_u = { .ip4_u =
330 				      { .daddr = ((opt && opt->srr) ?
331 						  opt->faddr :
332 						  ireq->rmt_addr),
333 					.saddr = ireq->loc_addr,
334 					.tos = RT_CONN_FLAGS(sk) } },
335 			    .proto = sk->sk_protocol,
336 			    .uli_u = { .ports =
337 				       { .sport = inet_sk(sk)->sport,
338 					 .dport = ireq->rmt_port } } };
339 
340 	security_req_classify_flow(req, &fl);
341 	if (ip_route_output_flow(sock_net(sk), &rt, &fl, sk, 0)) {
342 		IP_INC_STATS_BH(IPSTATS_MIB_OUTNOROUTES);
343 		return NULL;
344 	}
345 	if (opt && opt->is_strictroute && rt->rt_dst != rt->rt_gateway) {
346 		ip_rt_put(rt);
347 		IP_INC_STATS_BH(IPSTATS_MIB_OUTNOROUTES);
348 		return NULL;
349 	}
350 	return &rt->u.dst;
351 }
352 
353 EXPORT_SYMBOL_GPL(inet_csk_route_req);
354 
355 static inline u32 inet_synq_hash(const __be32 raddr, const __be16 rport,
356 				 const u32 rnd, const u32 synq_hsize)
357 {
358 	return jhash_2words((__force u32)raddr, (__force u32)rport, rnd) & (synq_hsize - 1);
359 }
360 
361 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
362 #define AF_INET_FAMILY(fam) ((fam) == AF_INET)
363 #else
364 #define AF_INET_FAMILY(fam) 1
365 #endif
366 
367 struct request_sock *inet_csk_search_req(const struct sock *sk,
368 					 struct request_sock ***prevp,
369 					 const __be16 rport, const __be32 raddr,
370 					 const __be32 laddr)
371 {
372 	const struct inet_connection_sock *icsk = inet_csk(sk);
373 	struct listen_sock *lopt = icsk->icsk_accept_queue.listen_opt;
374 	struct request_sock *req, **prev;
375 
376 	for (prev = &lopt->syn_table[inet_synq_hash(raddr, rport, lopt->hash_rnd,
377 						    lopt->nr_table_entries)];
378 	     (req = *prev) != NULL;
379 	     prev = &req->dl_next) {
380 		const struct inet_request_sock *ireq = inet_rsk(req);
381 
382 		if (ireq->rmt_port == rport &&
383 		    ireq->rmt_addr == raddr &&
384 		    ireq->loc_addr == laddr &&
385 		    AF_INET_FAMILY(req->rsk_ops->family)) {
386 			BUG_TRAP(!req->sk);
387 			*prevp = prev;
388 			break;
389 		}
390 	}
391 
392 	return req;
393 }
394 
395 EXPORT_SYMBOL_GPL(inet_csk_search_req);
396 
397 void inet_csk_reqsk_queue_hash_add(struct sock *sk, struct request_sock *req,
398 				   unsigned long timeout)
399 {
400 	struct inet_connection_sock *icsk = inet_csk(sk);
401 	struct listen_sock *lopt = icsk->icsk_accept_queue.listen_opt;
402 	const u32 h = inet_synq_hash(inet_rsk(req)->rmt_addr, inet_rsk(req)->rmt_port,
403 				     lopt->hash_rnd, lopt->nr_table_entries);
404 
405 	reqsk_queue_hash_req(&icsk->icsk_accept_queue, h, req, timeout);
406 	inet_csk_reqsk_queue_added(sk, timeout);
407 }
408 
409 /* Only thing we need from tcp.h */
410 extern int sysctl_tcp_synack_retries;
411 
412 EXPORT_SYMBOL_GPL(inet_csk_reqsk_queue_hash_add);
413 
414 void inet_csk_reqsk_queue_prune(struct sock *parent,
415 				const unsigned long interval,
416 				const unsigned long timeout,
417 				const unsigned long max_rto)
418 {
419 	struct inet_connection_sock *icsk = inet_csk(parent);
420 	struct request_sock_queue *queue = &icsk->icsk_accept_queue;
421 	struct listen_sock *lopt = queue->listen_opt;
422 	int thresh = icsk->icsk_syn_retries ? : sysctl_tcp_synack_retries;
423 	unsigned long now = jiffies;
424 	struct request_sock **reqp, *req;
425 	int i, budget;
426 
427 	if (lopt == NULL || lopt->qlen == 0)
428 		return;
429 
430 	/* Normally all the openreqs are young and become mature
431 	 * (i.e. converted to established socket) for first timeout.
432 	 * If synack was not acknowledged for 3 seconds, it means
433 	 * one of the following things: synack was lost, ack was lost,
434 	 * rtt is high or nobody planned to ack (i.e. synflood).
435 	 * When server is a bit loaded, queue is populated with old
436 	 * open requests, reducing effective size of queue.
437 	 * When server is well loaded, queue size reduces to zero
438 	 * after several minutes of work. It is not synflood,
439 	 * it is normal operation. The solution is pruning
440 	 * too old entries overriding normal timeout, when
441 	 * situation becomes dangerous.
442 	 *
443 	 * Essentially, we reserve half of room for young
444 	 * embrions; and abort old ones without pity, if old
445 	 * ones are about to clog our table.
446 	 */
447 	if (lopt->qlen>>(lopt->max_qlen_log-1)) {
448 		int young = (lopt->qlen_young<<1);
449 
450 		while (thresh > 2) {
451 			if (lopt->qlen < young)
452 				break;
453 			thresh--;
454 			young <<= 1;
455 		}
456 	}
457 
458 	budget = 2 * (lopt->nr_table_entries / (timeout / interval));
459 	i = lopt->clock_hand;
460 
461 	do {
462 		reqp=&lopt->syn_table[i];
463 		while ((req = *reqp) != NULL) {
464 			if (time_after_eq(now, req->expires)) {
465 				if (req->retrans < thresh &&
466 				    !req->rsk_ops->rtx_syn_ack(parent, req)) {
467 					unsigned long timeo;
468 
469 					if (req->retrans++ == 0)
470 						lopt->qlen_young--;
471 					timeo = min((timeout << req->retrans), max_rto);
472 					req->expires = now + timeo;
473 					reqp = &req->dl_next;
474 					continue;
475 				}
476 
477 				/* Drop this request */
478 				inet_csk_reqsk_queue_unlink(parent, req, reqp);
479 				reqsk_queue_removed(queue, req);
480 				reqsk_free(req);
481 				continue;
482 			}
483 			reqp = &req->dl_next;
484 		}
485 
486 		i = (i + 1) & (lopt->nr_table_entries - 1);
487 
488 	} while (--budget > 0);
489 
490 	lopt->clock_hand = i;
491 
492 	if (lopt->qlen)
493 		inet_csk_reset_keepalive_timer(parent, interval);
494 }
495 
496 EXPORT_SYMBOL_GPL(inet_csk_reqsk_queue_prune);
497 
498 struct sock *inet_csk_clone(struct sock *sk, const struct request_sock *req,
499 			    const gfp_t priority)
500 {
501 	struct sock *newsk = sk_clone(sk, priority);
502 
503 	if (newsk != NULL) {
504 		struct inet_connection_sock *newicsk = inet_csk(newsk);
505 
506 		newsk->sk_state = TCP_SYN_RECV;
507 		newicsk->icsk_bind_hash = NULL;
508 
509 		inet_sk(newsk)->dport = inet_rsk(req)->rmt_port;
510 		newsk->sk_write_space = sk_stream_write_space;
511 
512 		newicsk->icsk_retransmits = 0;
513 		newicsk->icsk_backoff	  = 0;
514 		newicsk->icsk_probes_out  = 0;
515 
516 		/* Deinitialize accept_queue to trap illegal accesses. */
517 		memset(&newicsk->icsk_accept_queue, 0, sizeof(newicsk->icsk_accept_queue));
518 
519 		security_inet_csk_clone(newsk, req);
520 	}
521 	return newsk;
522 }
523 
524 EXPORT_SYMBOL_GPL(inet_csk_clone);
525 
526 /*
527  * At this point, there should be no process reference to this
528  * socket, and thus no user references at all.  Therefore we
529  * can assume the socket waitqueue is inactive and nobody will
530  * try to jump onto it.
531  */
532 void inet_csk_destroy_sock(struct sock *sk)
533 {
534 	BUG_TRAP(sk->sk_state == TCP_CLOSE);
535 	BUG_TRAP(sock_flag(sk, SOCK_DEAD));
536 
537 	/* It cannot be in hash table! */
538 	BUG_TRAP(sk_unhashed(sk));
539 
540 	/* If it has not 0 inet_sk(sk)->num, it must be bound */
541 	BUG_TRAP(!inet_sk(sk)->num || inet_csk(sk)->icsk_bind_hash);
542 
543 	sk->sk_prot->destroy(sk);
544 
545 	sk_stream_kill_queues(sk);
546 
547 	xfrm_sk_free_policy(sk);
548 
549 	sk_refcnt_debug_release(sk);
550 
551 	atomic_dec(sk->sk_prot->orphan_count);
552 	sock_put(sk);
553 }
554 
555 EXPORT_SYMBOL(inet_csk_destroy_sock);
556 
557 int inet_csk_listen_start(struct sock *sk, const int nr_table_entries)
558 {
559 	struct inet_sock *inet = inet_sk(sk);
560 	struct inet_connection_sock *icsk = inet_csk(sk);
561 	int rc = reqsk_queue_alloc(&icsk->icsk_accept_queue, nr_table_entries);
562 
563 	if (rc != 0)
564 		return rc;
565 
566 	sk->sk_max_ack_backlog = 0;
567 	sk->sk_ack_backlog = 0;
568 	inet_csk_delack_init(sk);
569 
570 	/* There is race window here: we announce ourselves listening,
571 	 * but this transition is still not validated by get_port().
572 	 * It is OK, because this socket enters to hash table only
573 	 * after validation is complete.
574 	 */
575 	sk->sk_state = TCP_LISTEN;
576 	if (!sk->sk_prot->get_port(sk, inet->num)) {
577 		inet->sport = htons(inet->num);
578 
579 		sk_dst_reset(sk);
580 		sk->sk_prot->hash(sk);
581 
582 		return 0;
583 	}
584 
585 	sk->sk_state = TCP_CLOSE;
586 	__reqsk_queue_destroy(&icsk->icsk_accept_queue);
587 	return -EADDRINUSE;
588 }
589 
590 EXPORT_SYMBOL_GPL(inet_csk_listen_start);
591 
592 /*
593  *	This routine closes sockets which have been at least partially
594  *	opened, but not yet accepted.
595  */
596 void inet_csk_listen_stop(struct sock *sk)
597 {
598 	struct inet_connection_sock *icsk = inet_csk(sk);
599 	struct request_sock *acc_req;
600 	struct request_sock *req;
601 
602 	inet_csk_delete_keepalive_timer(sk);
603 
604 	/* make all the listen_opt local to us */
605 	acc_req = reqsk_queue_yank_acceptq(&icsk->icsk_accept_queue);
606 
607 	/* Following specs, it would be better either to send FIN
608 	 * (and enter FIN-WAIT-1, it is normal close)
609 	 * or to send active reset (abort).
610 	 * Certainly, it is pretty dangerous while synflood, but it is
611 	 * bad justification for our negligence 8)
612 	 * To be honest, we are not able to make either
613 	 * of the variants now.			--ANK
614 	 */
615 	reqsk_queue_destroy(&icsk->icsk_accept_queue);
616 
617 	while ((req = acc_req) != NULL) {
618 		struct sock *child = req->sk;
619 
620 		acc_req = req->dl_next;
621 
622 		local_bh_disable();
623 		bh_lock_sock(child);
624 		BUG_TRAP(!sock_owned_by_user(child));
625 		sock_hold(child);
626 
627 		sk->sk_prot->disconnect(child, O_NONBLOCK);
628 
629 		sock_orphan(child);
630 
631 		atomic_inc(sk->sk_prot->orphan_count);
632 
633 		inet_csk_destroy_sock(child);
634 
635 		bh_unlock_sock(child);
636 		local_bh_enable();
637 		sock_put(child);
638 
639 		sk_acceptq_removed(sk);
640 		__reqsk_free(req);
641 	}
642 	BUG_TRAP(!sk->sk_ack_backlog);
643 }
644 
645 EXPORT_SYMBOL_GPL(inet_csk_listen_stop);
646 
647 void inet_csk_addr2sockaddr(struct sock *sk, struct sockaddr *uaddr)
648 {
649 	struct sockaddr_in *sin = (struct sockaddr_in *)uaddr;
650 	const struct inet_sock *inet = inet_sk(sk);
651 
652 	sin->sin_family		= AF_INET;
653 	sin->sin_addr.s_addr	= inet->daddr;
654 	sin->sin_port		= inet->dport;
655 }
656 
657 EXPORT_SYMBOL_GPL(inet_csk_addr2sockaddr);
658 
659 #ifdef CONFIG_COMPAT
660 int inet_csk_compat_getsockopt(struct sock *sk, int level, int optname,
661 			       char __user *optval, int __user *optlen)
662 {
663 	const struct inet_connection_sock *icsk = inet_csk(sk);
664 
665 	if (icsk->icsk_af_ops->compat_getsockopt != NULL)
666 		return icsk->icsk_af_ops->compat_getsockopt(sk, level, optname,
667 							    optval, optlen);
668 	return icsk->icsk_af_ops->getsockopt(sk, level, optname,
669 					     optval, optlen);
670 }
671 
672 EXPORT_SYMBOL_GPL(inet_csk_compat_getsockopt);
673 
674 int inet_csk_compat_setsockopt(struct sock *sk, int level, int optname,
675 			       char __user *optval, int optlen)
676 {
677 	const struct inet_connection_sock *icsk = inet_csk(sk);
678 
679 	if (icsk->icsk_af_ops->compat_setsockopt != NULL)
680 		return icsk->icsk_af_ops->compat_setsockopt(sk, level, optname,
681 							    optval, optlen);
682 	return icsk->icsk_af_ops->setsockopt(sk, level, optname,
683 					     optval, optlen);
684 }
685 
686 EXPORT_SYMBOL_GPL(inet_csk_compat_setsockopt);
687 #endif
688