xref: /linux/net/bluetooth/rfcomm/sock.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
1 /*
2    RFCOMM implementation for Linux Bluetooth stack (BlueZ).
3    Copyright (C) 2002 Maxim Krasnyansky <maxk@qualcomm.com>
4    Copyright (C) 2002 Marcel Holtmann <marcel@holtmann.org>
5 
6    This program is free software; you can redistribute it and/or modify
7    it under the terms of the GNU General Public License version 2 as
8    published by the Free Software Foundation;
9 
10    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
11    OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
12    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
13    IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY
14    CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES
15    WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16    ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
17    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18 
19    ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS,
20    COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS
21    SOFTWARE IS DISCLAIMED.
22 */
23 
24 /*
25  * RFCOMM sockets.
26  */
27 
28 #include <linux/export.h>
29 #include <linux/debugfs.h>
30 
31 #include <net/bluetooth/bluetooth.h>
32 #include <net/bluetooth/hci_core.h>
33 #include <net/bluetooth/l2cap.h>
34 #include <net/bluetooth/rfcomm.h>
35 
36 static const struct proto_ops rfcomm_sock_ops;
37 
38 static struct bt_sock_list rfcomm_sk_list = {
39 	.lock = __RW_LOCK_UNLOCKED(rfcomm_sk_list.lock)
40 };
41 
42 static void rfcomm_sock_close(struct sock *sk);
43 static void rfcomm_sock_kill(struct sock *sk);
44 
45 /* ---- DLC callbacks ----
46  *
47  * called under rfcomm_dlc_lock()
48  */
49 static void rfcomm_sk_data_ready(struct rfcomm_dlc *d, struct sk_buff *skb)
50 {
51 	struct sock *sk = d->owner;
52 	if (!sk)
53 		return;
54 
55 	atomic_add(skb->len, &sk->sk_rmem_alloc);
56 	skb_queue_tail(&sk->sk_receive_queue, skb);
57 	sk->sk_data_ready(sk);
58 
59 	if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf)
60 		rfcomm_dlc_throttle(d);
61 }
62 
63 static void rfcomm_sk_state_change(struct rfcomm_dlc *d, int err)
64 {
65 	struct sock *sk = d->owner, *parent;
66 	unsigned long flags;
67 
68 	if (!sk)
69 		return;
70 
71 	BT_DBG("dlc %p state %ld err %d", d, d->state, err);
72 
73 	local_irq_save(flags);
74 	bh_lock_sock(sk);
75 
76 	if (err)
77 		sk->sk_err = err;
78 
79 	sk->sk_state = d->state;
80 
81 	parent = bt_sk(sk)->parent;
82 	if (parent) {
83 		if (d->state == BT_CLOSED) {
84 			sock_set_flag(sk, SOCK_ZAPPED);
85 			bt_accept_unlink(sk);
86 		}
87 		parent->sk_data_ready(parent);
88 	} else {
89 		if (d->state == BT_CONNECTED)
90 			rfcomm_session_getaddr(d->session,
91 					       &rfcomm_pi(sk)->src, NULL);
92 		sk->sk_state_change(sk);
93 	}
94 
95 	bh_unlock_sock(sk);
96 	local_irq_restore(flags);
97 
98 	if (parent && sock_flag(sk, SOCK_ZAPPED)) {
99 		/* We have to drop DLC lock here, otherwise
100 		 * rfcomm_sock_destruct() will dead lock. */
101 		rfcomm_dlc_unlock(d);
102 		rfcomm_sock_kill(sk);
103 		rfcomm_dlc_lock(d);
104 	}
105 }
106 
107 /* ---- Socket functions ---- */
108 static struct sock *__rfcomm_get_listen_sock_by_addr(u8 channel, bdaddr_t *src)
109 {
110 	struct sock *sk = NULL;
111 
112 	sk_for_each(sk, &rfcomm_sk_list.head) {
113 		if (rfcomm_pi(sk)->channel != channel)
114 			continue;
115 
116 		if (bacmp(&rfcomm_pi(sk)->src, src))
117 			continue;
118 
119 		if (sk->sk_state == BT_BOUND || sk->sk_state == BT_LISTEN)
120 			break;
121 	}
122 
123 	return sk ? sk : NULL;
124 }
125 
126 /* Find socket with channel and source bdaddr.
127  * Returns closest match.
128  */
129 static struct sock *rfcomm_get_sock_by_channel(int state, u8 channel, bdaddr_t *src)
130 {
131 	struct sock *sk = NULL, *sk1 = NULL;
132 
133 	read_lock(&rfcomm_sk_list.lock);
134 
135 	sk_for_each(sk, &rfcomm_sk_list.head) {
136 		if (state && sk->sk_state != state)
137 			continue;
138 
139 		if (rfcomm_pi(sk)->channel == channel) {
140 			/* Exact match. */
141 			if (!bacmp(&rfcomm_pi(sk)->src, src))
142 				break;
143 
144 			/* Closest match */
145 			if (!bacmp(&rfcomm_pi(sk)->src, BDADDR_ANY))
146 				sk1 = sk;
147 		}
148 	}
149 
150 	read_unlock(&rfcomm_sk_list.lock);
151 
152 	return sk ? sk : sk1;
153 }
154 
155 static void rfcomm_sock_destruct(struct sock *sk)
156 {
157 	struct rfcomm_dlc *d = rfcomm_pi(sk)->dlc;
158 
159 	BT_DBG("sk %p dlc %p", sk, d);
160 
161 	skb_queue_purge(&sk->sk_receive_queue);
162 	skb_queue_purge(&sk->sk_write_queue);
163 
164 	rfcomm_dlc_lock(d);
165 	rfcomm_pi(sk)->dlc = NULL;
166 
167 	/* Detach DLC if it's owned by this socket */
168 	if (d->owner == sk)
169 		d->owner = NULL;
170 	rfcomm_dlc_unlock(d);
171 
172 	rfcomm_dlc_put(d);
173 }
174 
175 static void rfcomm_sock_cleanup_listen(struct sock *parent)
176 {
177 	struct sock *sk;
178 
179 	BT_DBG("parent %p", parent);
180 
181 	/* Close not yet accepted dlcs */
182 	while ((sk = bt_accept_dequeue(parent, NULL))) {
183 		rfcomm_sock_close(sk);
184 		rfcomm_sock_kill(sk);
185 	}
186 
187 	parent->sk_state  = BT_CLOSED;
188 	sock_set_flag(parent, SOCK_ZAPPED);
189 }
190 
191 /* Kill socket (only if zapped and orphan)
192  * Must be called on unlocked socket.
193  */
194 static void rfcomm_sock_kill(struct sock *sk)
195 {
196 	if (!sock_flag(sk, SOCK_ZAPPED) || sk->sk_socket)
197 		return;
198 
199 	BT_DBG("sk %p state %d refcnt %d", sk, sk->sk_state, atomic_read(&sk->sk_refcnt));
200 
201 	/* Kill poor orphan */
202 	bt_sock_unlink(&rfcomm_sk_list, sk);
203 	sock_set_flag(sk, SOCK_DEAD);
204 	sock_put(sk);
205 }
206 
207 static void __rfcomm_sock_close(struct sock *sk)
208 {
209 	struct rfcomm_dlc *d = rfcomm_pi(sk)->dlc;
210 
211 	BT_DBG("sk %p state %d socket %p", sk, sk->sk_state, sk->sk_socket);
212 
213 	switch (sk->sk_state) {
214 	case BT_LISTEN:
215 		rfcomm_sock_cleanup_listen(sk);
216 		break;
217 
218 	case BT_CONNECT:
219 	case BT_CONNECT2:
220 	case BT_CONFIG:
221 	case BT_CONNECTED:
222 		rfcomm_dlc_close(d, 0);
223 
224 	default:
225 		sock_set_flag(sk, SOCK_ZAPPED);
226 		break;
227 	}
228 }
229 
230 /* Close socket.
231  * Must be called on unlocked socket.
232  */
233 static void rfcomm_sock_close(struct sock *sk)
234 {
235 	lock_sock(sk);
236 	__rfcomm_sock_close(sk);
237 	release_sock(sk);
238 }
239 
240 static void rfcomm_sock_init(struct sock *sk, struct sock *parent)
241 {
242 	struct rfcomm_pinfo *pi = rfcomm_pi(sk);
243 
244 	BT_DBG("sk %p", sk);
245 
246 	if (parent) {
247 		sk->sk_type = parent->sk_type;
248 		pi->dlc->defer_setup = test_bit(BT_SK_DEFER_SETUP,
249 						&bt_sk(parent)->flags);
250 
251 		pi->sec_level = rfcomm_pi(parent)->sec_level;
252 		pi->role_switch = rfcomm_pi(parent)->role_switch;
253 
254 		security_sk_clone(parent, sk);
255 	} else {
256 		pi->dlc->defer_setup = 0;
257 
258 		pi->sec_level = BT_SECURITY_LOW;
259 		pi->role_switch = 0;
260 	}
261 
262 	pi->dlc->sec_level = pi->sec_level;
263 	pi->dlc->role_switch = pi->role_switch;
264 }
265 
266 static struct proto rfcomm_proto = {
267 	.name		= "RFCOMM",
268 	.owner		= THIS_MODULE,
269 	.obj_size	= sizeof(struct rfcomm_pinfo)
270 };
271 
272 static struct sock *rfcomm_sock_alloc(struct net *net, struct socket *sock, int proto, gfp_t prio, int kern)
273 {
274 	struct rfcomm_dlc *d;
275 	struct sock *sk;
276 
277 	sk = sk_alloc(net, PF_BLUETOOTH, prio, &rfcomm_proto, kern);
278 	if (!sk)
279 		return NULL;
280 
281 	sock_init_data(sock, sk);
282 	INIT_LIST_HEAD(&bt_sk(sk)->accept_q);
283 
284 	d = rfcomm_dlc_alloc(prio);
285 	if (!d) {
286 		sk_free(sk);
287 		return NULL;
288 	}
289 
290 	d->data_ready   = rfcomm_sk_data_ready;
291 	d->state_change = rfcomm_sk_state_change;
292 
293 	rfcomm_pi(sk)->dlc = d;
294 	d->owner = sk;
295 
296 	sk->sk_destruct = rfcomm_sock_destruct;
297 	sk->sk_sndtimeo = RFCOMM_CONN_TIMEOUT;
298 
299 	sk->sk_sndbuf = RFCOMM_MAX_CREDITS * RFCOMM_DEFAULT_MTU * 10;
300 	sk->sk_rcvbuf = RFCOMM_MAX_CREDITS * RFCOMM_DEFAULT_MTU * 10;
301 
302 	sock_reset_flag(sk, SOCK_ZAPPED);
303 
304 	sk->sk_protocol = proto;
305 	sk->sk_state    = BT_OPEN;
306 
307 	bt_sock_link(&rfcomm_sk_list, sk);
308 
309 	BT_DBG("sk %p", sk);
310 	return sk;
311 }
312 
313 static int rfcomm_sock_create(struct net *net, struct socket *sock,
314 			      int protocol, int kern)
315 {
316 	struct sock *sk;
317 
318 	BT_DBG("sock %p", sock);
319 
320 	sock->state = SS_UNCONNECTED;
321 
322 	if (sock->type != SOCK_STREAM && sock->type != SOCK_RAW)
323 		return -ESOCKTNOSUPPORT;
324 
325 	sock->ops = &rfcomm_sock_ops;
326 
327 	sk = rfcomm_sock_alloc(net, sock, protocol, GFP_ATOMIC, kern);
328 	if (!sk)
329 		return -ENOMEM;
330 
331 	rfcomm_sock_init(sk, NULL);
332 	return 0;
333 }
334 
335 static int rfcomm_sock_bind(struct socket *sock, struct sockaddr *addr, int addr_len)
336 {
337 	struct sockaddr_rc sa;
338 	struct sock *sk = sock->sk;
339 	int len, err = 0;
340 
341 	if (!addr || addr->sa_family != AF_BLUETOOTH)
342 		return -EINVAL;
343 
344 	memset(&sa, 0, sizeof(sa));
345 	len = min_t(unsigned int, sizeof(sa), addr_len);
346 	memcpy(&sa, addr, len);
347 
348 	BT_DBG("sk %p %pMR", sk, &sa.rc_bdaddr);
349 
350 	lock_sock(sk);
351 
352 	if (sk->sk_state != BT_OPEN) {
353 		err = -EBADFD;
354 		goto done;
355 	}
356 
357 	if (sk->sk_type != SOCK_STREAM) {
358 		err = -EINVAL;
359 		goto done;
360 	}
361 
362 	write_lock(&rfcomm_sk_list.lock);
363 
364 	if (sa.rc_channel &&
365 	    __rfcomm_get_listen_sock_by_addr(sa.rc_channel, &sa.rc_bdaddr)) {
366 		err = -EADDRINUSE;
367 	} else {
368 		/* Save source address */
369 		bacpy(&rfcomm_pi(sk)->src, &sa.rc_bdaddr);
370 		rfcomm_pi(sk)->channel = sa.rc_channel;
371 		sk->sk_state = BT_BOUND;
372 	}
373 
374 	write_unlock(&rfcomm_sk_list.lock);
375 
376 done:
377 	release_sock(sk);
378 	return err;
379 }
380 
381 static int rfcomm_sock_connect(struct socket *sock, struct sockaddr *addr, int alen, int flags)
382 {
383 	struct sockaddr_rc *sa = (struct sockaddr_rc *) addr;
384 	struct sock *sk = sock->sk;
385 	struct rfcomm_dlc *d = rfcomm_pi(sk)->dlc;
386 	int err = 0;
387 
388 	BT_DBG("sk %p", sk);
389 
390 	if (alen < sizeof(struct sockaddr_rc) ||
391 	    addr->sa_family != AF_BLUETOOTH)
392 		return -EINVAL;
393 
394 	lock_sock(sk);
395 
396 	if (sk->sk_state != BT_OPEN && sk->sk_state != BT_BOUND) {
397 		err = -EBADFD;
398 		goto done;
399 	}
400 
401 	if (sk->sk_type != SOCK_STREAM) {
402 		err = -EINVAL;
403 		goto done;
404 	}
405 
406 	sk->sk_state = BT_CONNECT;
407 	bacpy(&rfcomm_pi(sk)->dst, &sa->rc_bdaddr);
408 	rfcomm_pi(sk)->channel = sa->rc_channel;
409 
410 	d->sec_level = rfcomm_pi(sk)->sec_level;
411 	d->role_switch = rfcomm_pi(sk)->role_switch;
412 
413 	err = rfcomm_dlc_open(d, &rfcomm_pi(sk)->src, &sa->rc_bdaddr,
414 			      sa->rc_channel);
415 	if (!err)
416 		err = bt_sock_wait_state(sk, BT_CONNECTED,
417 				sock_sndtimeo(sk, flags & O_NONBLOCK));
418 
419 done:
420 	release_sock(sk);
421 	return err;
422 }
423 
424 static int rfcomm_sock_listen(struct socket *sock, int backlog)
425 {
426 	struct sock *sk = sock->sk;
427 	int err = 0;
428 
429 	BT_DBG("sk %p backlog %d", sk, backlog);
430 
431 	lock_sock(sk);
432 
433 	if (sk->sk_state != BT_BOUND) {
434 		err = -EBADFD;
435 		goto done;
436 	}
437 
438 	if (sk->sk_type != SOCK_STREAM) {
439 		err = -EINVAL;
440 		goto done;
441 	}
442 
443 	if (!rfcomm_pi(sk)->channel) {
444 		bdaddr_t *src = &rfcomm_pi(sk)->src;
445 		u8 channel;
446 
447 		err = -EINVAL;
448 
449 		write_lock(&rfcomm_sk_list.lock);
450 
451 		for (channel = 1; channel < 31; channel++)
452 			if (!__rfcomm_get_listen_sock_by_addr(channel, src)) {
453 				rfcomm_pi(sk)->channel = channel;
454 				err = 0;
455 				break;
456 			}
457 
458 		write_unlock(&rfcomm_sk_list.lock);
459 
460 		if (err < 0)
461 			goto done;
462 	}
463 
464 	sk->sk_max_ack_backlog = backlog;
465 	sk->sk_ack_backlog = 0;
466 	sk->sk_state = BT_LISTEN;
467 
468 done:
469 	release_sock(sk);
470 	return err;
471 }
472 
473 static int rfcomm_sock_accept(struct socket *sock, struct socket *newsock, int flags)
474 {
475 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
476 	struct sock *sk = sock->sk, *nsk;
477 	long timeo;
478 	int err = 0;
479 
480 	lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
481 
482 	if (sk->sk_type != SOCK_STREAM) {
483 		err = -EINVAL;
484 		goto done;
485 	}
486 
487 	timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
488 
489 	BT_DBG("sk %p timeo %ld", sk, timeo);
490 
491 	/* Wait for an incoming connection. (wake-one). */
492 	add_wait_queue_exclusive(sk_sleep(sk), &wait);
493 	while (1) {
494 		if (sk->sk_state != BT_LISTEN) {
495 			err = -EBADFD;
496 			break;
497 		}
498 
499 		nsk = bt_accept_dequeue(sk, newsock);
500 		if (nsk)
501 			break;
502 
503 		if (!timeo) {
504 			err = -EAGAIN;
505 			break;
506 		}
507 
508 		if (signal_pending(current)) {
509 			err = sock_intr_errno(timeo);
510 			break;
511 		}
512 
513 		release_sock(sk);
514 
515 		timeo = wait_woken(&wait, TASK_INTERRUPTIBLE, timeo);
516 
517 		lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
518 	}
519 	remove_wait_queue(sk_sleep(sk), &wait);
520 
521 	if (err)
522 		goto done;
523 
524 	newsock->state = SS_CONNECTED;
525 
526 	BT_DBG("new socket %p", nsk);
527 
528 done:
529 	release_sock(sk);
530 	return err;
531 }
532 
533 static int rfcomm_sock_getname(struct socket *sock, struct sockaddr *addr, int *len, int peer)
534 {
535 	struct sockaddr_rc *sa = (struct sockaddr_rc *) addr;
536 	struct sock *sk = sock->sk;
537 
538 	BT_DBG("sock %p, sk %p", sock, sk);
539 
540 	if (peer && sk->sk_state != BT_CONNECTED &&
541 	    sk->sk_state != BT_CONNECT && sk->sk_state != BT_CONNECT2)
542 		return -ENOTCONN;
543 
544 	memset(sa, 0, sizeof(*sa));
545 	sa->rc_family  = AF_BLUETOOTH;
546 	sa->rc_channel = rfcomm_pi(sk)->channel;
547 	if (peer)
548 		bacpy(&sa->rc_bdaddr, &rfcomm_pi(sk)->dst);
549 	else
550 		bacpy(&sa->rc_bdaddr, &rfcomm_pi(sk)->src);
551 
552 	*len = sizeof(struct sockaddr_rc);
553 	return 0;
554 }
555 
556 static int rfcomm_sock_sendmsg(struct socket *sock, struct msghdr *msg,
557 			       size_t len)
558 {
559 	struct sock *sk = sock->sk;
560 	struct rfcomm_dlc *d = rfcomm_pi(sk)->dlc;
561 	struct sk_buff *skb;
562 	int sent;
563 
564 	if (test_bit(RFCOMM_DEFER_SETUP, &d->flags))
565 		return -ENOTCONN;
566 
567 	if (msg->msg_flags & MSG_OOB)
568 		return -EOPNOTSUPP;
569 
570 	if (sk->sk_shutdown & SEND_SHUTDOWN)
571 		return -EPIPE;
572 
573 	BT_DBG("sock %p, sk %p", sock, sk);
574 
575 	lock_sock(sk);
576 
577 	sent = bt_sock_wait_ready(sk, msg->msg_flags);
578 	if (sent)
579 		goto done;
580 
581 	while (len) {
582 		size_t size = min_t(size_t, len, d->mtu);
583 		int err;
584 
585 		skb = sock_alloc_send_skb(sk, size + RFCOMM_SKB_RESERVE,
586 				msg->msg_flags & MSG_DONTWAIT, &err);
587 		if (!skb) {
588 			if (sent == 0)
589 				sent = err;
590 			break;
591 		}
592 		skb_reserve(skb, RFCOMM_SKB_HEAD_RESERVE);
593 
594 		err = memcpy_from_msg(skb_put(skb, size), msg, size);
595 		if (err) {
596 			kfree_skb(skb);
597 			if (sent == 0)
598 				sent = err;
599 			break;
600 		}
601 
602 		skb->priority = sk->sk_priority;
603 
604 		err = rfcomm_dlc_send(d, skb);
605 		if (err < 0) {
606 			kfree_skb(skb);
607 			if (sent == 0)
608 				sent = err;
609 			break;
610 		}
611 
612 		sent += size;
613 		len  -= size;
614 	}
615 
616 done:
617 	release_sock(sk);
618 
619 	return sent;
620 }
621 
622 static int rfcomm_sock_recvmsg(struct socket *sock, struct msghdr *msg,
623 			       size_t size, int flags)
624 {
625 	struct sock *sk = sock->sk;
626 	struct rfcomm_dlc *d = rfcomm_pi(sk)->dlc;
627 	int len;
628 
629 	if (test_and_clear_bit(RFCOMM_DEFER_SETUP, &d->flags)) {
630 		rfcomm_dlc_accept(d);
631 		return 0;
632 	}
633 
634 	len = bt_sock_stream_recvmsg(sock, msg, size, flags);
635 
636 	lock_sock(sk);
637 	if (!(flags & MSG_PEEK) && len > 0)
638 		atomic_sub(len, &sk->sk_rmem_alloc);
639 
640 	if (atomic_read(&sk->sk_rmem_alloc) <= (sk->sk_rcvbuf >> 2))
641 		rfcomm_dlc_unthrottle(rfcomm_pi(sk)->dlc);
642 	release_sock(sk);
643 
644 	return len;
645 }
646 
647 static int rfcomm_sock_setsockopt_old(struct socket *sock, int optname, char __user *optval, unsigned int optlen)
648 {
649 	struct sock *sk = sock->sk;
650 	int err = 0;
651 	u32 opt;
652 
653 	BT_DBG("sk %p", sk);
654 
655 	lock_sock(sk);
656 
657 	switch (optname) {
658 	case RFCOMM_LM:
659 		if (get_user(opt, (u32 __user *) optval)) {
660 			err = -EFAULT;
661 			break;
662 		}
663 
664 		if (opt & RFCOMM_LM_FIPS) {
665 			err = -EINVAL;
666 			break;
667 		}
668 
669 		if (opt & RFCOMM_LM_AUTH)
670 			rfcomm_pi(sk)->sec_level = BT_SECURITY_LOW;
671 		if (opt & RFCOMM_LM_ENCRYPT)
672 			rfcomm_pi(sk)->sec_level = BT_SECURITY_MEDIUM;
673 		if (opt & RFCOMM_LM_SECURE)
674 			rfcomm_pi(sk)->sec_level = BT_SECURITY_HIGH;
675 
676 		rfcomm_pi(sk)->role_switch = (opt & RFCOMM_LM_MASTER);
677 		break;
678 
679 	default:
680 		err = -ENOPROTOOPT;
681 		break;
682 	}
683 
684 	release_sock(sk);
685 	return err;
686 }
687 
688 static int rfcomm_sock_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen)
689 {
690 	struct sock *sk = sock->sk;
691 	struct bt_security sec;
692 	int err = 0;
693 	size_t len;
694 	u32 opt;
695 
696 	BT_DBG("sk %p", sk);
697 
698 	if (level == SOL_RFCOMM)
699 		return rfcomm_sock_setsockopt_old(sock, optname, optval, optlen);
700 
701 	if (level != SOL_BLUETOOTH)
702 		return -ENOPROTOOPT;
703 
704 	lock_sock(sk);
705 
706 	switch (optname) {
707 	case BT_SECURITY:
708 		if (sk->sk_type != SOCK_STREAM) {
709 			err = -EINVAL;
710 			break;
711 		}
712 
713 		sec.level = BT_SECURITY_LOW;
714 
715 		len = min_t(unsigned int, sizeof(sec), optlen);
716 		if (copy_from_user((char *) &sec, optval, len)) {
717 			err = -EFAULT;
718 			break;
719 		}
720 
721 		if (sec.level > BT_SECURITY_HIGH) {
722 			err = -EINVAL;
723 			break;
724 		}
725 
726 		rfcomm_pi(sk)->sec_level = sec.level;
727 		break;
728 
729 	case BT_DEFER_SETUP:
730 		if (sk->sk_state != BT_BOUND && sk->sk_state != BT_LISTEN) {
731 			err = -EINVAL;
732 			break;
733 		}
734 
735 		if (get_user(opt, (u32 __user *) optval)) {
736 			err = -EFAULT;
737 			break;
738 		}
739 
740 		if (opt)
741 			set_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags);
742 		else
743 			clear_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags);
744 
745 		break;
746 
747 	default:
748 		err = -ENOPROTOOPT;
749 		break;
750 	}
751 
752 	release_sock(sk);
753 	return err;
754 }
755 
756 static int rfcomm_sock_getsockopt_old(struct socket *sock, int optname, char __user *optval, int __user *optlen)
757 {
758 	struct sock *sk = sock->sk;
759 	struct sock *l2cap_sk;
760 	struct l2cap_conn *conn;
761 	struct rfcomm_conninfo cinfo;
762 	int len, err = 0;
763 	u32 opt;
764 
765 	BT_DBG("sk %p", sk);
766 
767 	if (get_user(len, optlen))
768 		return -EFAULT;
769 
770 	lock_sock(sk);
771 
772 	switch (optname) {
773 	case RFCOMM_LM:
774 		switch (rfcomm_pi(sk)->sec_level) {
775 		case BT_SECURITY_LOW:
776 			opt = RFCOMM_LM_AUTH;
777 			break;
778 		case BT_SECURITY_MEDIUM:
779 			opt = RFCOMM_LM_AUTH | RFCOMM_LM_ENCRYPT;
780 			break;
781 		case BT_SECURITY_HIGH:
782 			opt = RFCOMM_LM_AUTH | RFCOMM_LM_ENCRYPT |
783 			      RFCOMM_LM_SECURE;
784 			break;
785 		case BT_SECURITY_FIPS:
786 			opt = RFCOMM_LM_AUTH | RFCOMM_LM_ENCRYPT |
787 			      RFCOMM_LM_SECURE | RFCOMM_LM_FIPS;
788 			break;
789 		default:
790 			opt = 0;
791 			break;
792 		}
793 
794 		if (rfcomm_pi(sk)->role_switch)
795 			opt |= RFCOMM_LM_MASTER;
796 
797 		if (put_user(opt, (u32 __user *) optval))
798 			err = -EFAULT;
799 
800 		break;
801 
802 	case RFCOMM_CONNINFO:
803 		if (sk->sk_state != BT_CONNECTED &&
804 					!rfcomm_pi(sk)->dlc->defer_setup) {
805 			err = -ENOTCONN;
806 			break;
807 		}
808 
809 		l2cap_sk = rfcomm_pi(sk)->dlc->session->sock->sk;
810 		conn = l2cap_pi(l2cap_sk)->chan->conn;
811 
812 		memset(&cinfo, 0, sizeof(cinfo));
813 		cinfo.hci_handle = conn->hcon->handle;
814 		memcpy(cinfo.dev_class, conn->hcon->dev_class, 3);
815 
816 		len = min_t(unsigned int, len, sizeof(cinfo));
817 		if (copy_to_user(optval, (char *) &cinfo, len))
818 			err = -EFAULT;
819 
820 		break;
821 
822 	default:
823 		err = -ENOPROTOOPT;
824 		break;
825 	}
826 
827 	release_sock(sk);
828 	return err;
829 }
830 
831 static int rfcomm_sock_getsockopt(struct socket *sock, int level, int optname, char __user *optval, int __user *optlen)
832 {
833 	struct sock *sk = sock->sk;
834 	struct bt_security sec;
835 	int len, err = 0;
836 
837 	BT_DBG("sk %p", sk);
838 
839 	if (level == SOL_RFCOMM)
840 		return rfcomm_sock_getsockopt_old(sock, optname, optval, optlen);
841 
842 	if (level != SOL_BLUETOOTH)
843 		return -ENOPROTOOPT;
844 
845 	if (get_user(len, optlen))
846 		return -EFAULT;
847 
848 	lock_sock(sk);
849 
850 	switch (optname) {
851 	case BT_SECURITY:
852 		if (sk->sk_type != SOCK_STREAM) {
853 			err = -EINVAL;
854 			break;
855 		}
856 
857 		sec.level = rfcomm_pi(sk)->sec_level;
858 		sec.key_size = 0;
859 
860 		len = min_t(unsigned int, len, sizeof(sec));
861 		if (copy_to_user(optval, (char *) &sec, len))
862 			err = -EFAULT;
863 
864 		break;
865 
866 	case BT_DEFER_SETUP:
867 		if (sk->sk_state != BT_BOUND && sk->sk_state != BT_LISTEN) {
868 			err = -EINVAL;
869 			break;
870 		}
871 
872 		if (put_user(test_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags),
873 			     (u32 __user *) optval))
874 			err = -EFAULT;
875 
876 		break;
877 
878 	default:
879 		err = -ENOPROTOOPT;
880 		break;
881 	}
882 
883 	release_sock(sk);
884 	return err;
885 }
886 
887 static int rfcomm_sock_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
888 {
889 	struct sock *sk __maybe_unused = sock->sk;
890 	int err;
891 
892 	BT_DBG("sk %p cmd %x arg %lx", sk, cmd, arg);
893 
894 	err = bt_sock_ioctl(sock, cmd, arg);
895 
896 	if (err == -ENOIOCTLCMD) {
897 #ifdef CONFIG_BT_RFCOMM_TTY
898 		lock_sock(sk);
899 		err = rfcomm_dev_ioctl(sk, cmd, (void __user *) arg);
900 		release_sock(sk);
901 #else
902 		err = -EOPNOTSUPP;
903 #endif
904 	}
905 
906 	return err;
907 }
908 
909 static int rfcomm_sock_shutdown(struct socket *sock, int how)
910 {
911 	struct sock *sk = sock->sk;
912 	int err = 0;
913 
914 	BT_DBG("sock %p, sk %p", sock, sk);
915 
916 	if (!sk)
917 		return 0;
918 
919 	lock_sock(sk);
920 	if (!sk->sk_shutdown) {
921 		sk->sk_shutdown = SHUTDOWN_MASK;
922 		__rfcomm_sock_close(sk);
923 
924 		if (sock_flag(sk, SOCK_LINGER) && sk->sk_lingertime &&
925 		    !(current->flags & PF_EXITING))
926 			err = bt_sock_wait_state(sk, BT_CLOSED, sk->sk_lingertime);
927 	}
928 	release_sock(sk);
929 	return err;
930 }
931 
932 static int rfcomm_sock_release(struct socket *sock)
933 {
934 	struct sock *sk = sock->sk;
935 	int err;
936 
937 	BT_DBG("sock %p, sk %p", sock, sk);
938 
939 	if (!sk)
940 		return 0;
941 
942 	err = rfcomm_sock_shutdown(sock, 2);
943 
944 	sock_orphan(sk);
945 	rfcomm_sock_kill(sk);
946 	return err;
947 }
948 
949 /* ---- RFCOMM core layer callbacks ----
950  *
951  * called under rfcomm_lock()
952  */
953 int rfcomm_connect_ind(struct rfcomm_session *s, u8 channel, struct rfcomm_dlc **d)
954 {
955 	struct sock *sk, *parent;
956 	bdaddr_t src, dst;
957 	int result = 0;
958 
959 	BT_DBG("session %p channel %d", s, channel);
960 
961 	rfcomm_session_getaddr(s, &src, &dst);
962 
963 	/* Check if we have socket listening on channel */
964 	parent = rfcomm_get_sock_by_channel(BT_LISTEN, channel, &src);
965 	if (!parent)
966 		return 0;
967 
968 	bh_lock_sock(parent);
969 
970 	/* Check for backlog size */
971 	if (sk_acceptq_is_full(parent)) {
972 		BT_DBG("backlog full %d", parent->sk_ack_backlog);
973 		goto done;
974 	}
975 
976 	sk = rfcomm_sock_alloc(sock_net(parent), NULL, BTPROTO_RFCOMM, GFP_ATOMIC, 0);
977 	if (!sk)
978 		goto done;
979 
980 	bt_sock_reclassify_lock(sk, BTPROTO_RFCOMM);
981 
982 	rfcomm_sock_init(sk, parent);
983 	bacpy(&rfcomm_pi(sk)->src, &src);
984 	bacpy(&rfcomm_pi(sk)->dst, &dst);
985 	rfcomm_pi(sk)->channel = channel;
986 
987 	sk->sk_state = BT_CONFIG;
988 	bt_accept_enqueue(parent, sk);
989 
990 	/* Accept connection and return socket DLC */
991 	*d = rfcomm_pi(sk)->dlc;
992 	result = 1;
993 
994 done:
995 	bh_unlock_sock(parent);
996 
997 	if (test_bit(BT_SK_DEFER_SETUP, &bt_sk(parent)->flags))
998 		parent->sk_state_change(parent);
999 
1000 	return result;
1001 }
1002 
1003 static int rfcomm_sock_debugfs_show(struct seq_file *f, void *p)
1004 {
1005 	struct sock *sk;
1006 
1007 	read_lock(&rfcomm_sk_list.lock);
1008 
1009 	sk_for_each(sk, &rfcomm_sk_list.head) {
1010 		seq_printf(f, "%pMR %pMR %d %d\n",
1011 			   &rfcomm_pi(sk)->src, &rfcomm_pi(sk)->dst,
1012 			   sk->sk_state, rfcomm_pi(sk)->channel);
1013 	}
1014 
1015 	read_unlock(&rfcomm_sk_list.lock);
1016 
1017 	return 0;
1018 }
1019 
1020 static int rfcomm_sock_debugfs_open(struct inode *inode, struct file *file)
1021 {
1022 	return single_open(file, rfcomm_sock_debugfs_show, inode->i_private);
1023 }
1024 
1025 static const struct file_operations rfcomm_sock_debugfs_fops = {
1026 	.open		= rfcomm_sock_debugfs_open,
1027 	.read		= seq_read,
1028 	.llseek		= seq_lseek,
1029 	.release	= single_release,
1030 };
1031 
1032 static struct dentry *rfcomm_sock_debugfs;
1033 
1034 static const struct proto_ops rfcomm_sock_ops = {
1035 	.family		= PF_BLUETOOTH,
1036 	.owner		= THIS_MODULE,
1037 	.release	= rfcomm_sock_release,
1038 	.bind		= rfcomm_sock_bind,
1039 	.connect	= rfcomm_sock_connect,
1040 	.listen		= rfcomm_sock_listen,
1041 	.accept		= rfcomm_sock_accept,
1042 	.getname	= rfcomm_sock_getname,
1043 	.sendmsg	= rfcomm_sock_sendmsg,
1044 	.recvmsg	= rfcomm_sock_recvmsg,
1045 	.shutdown	= rfcomm_sock_shutdown,
1046 	.setsockopt	= rfcomm_sock_setsockopt,
1047 	.getsockopt	= rfcomm_sock_getsockopt,
1048 	.ioctl		= rfcomm_sock_ioctl,
1049 	.poll		= bt_sock_poll,
1050 	.socketpair	= sock_no_socketpair,
1051 	.mmap		= sock_no_mmap
1052 };
1053 
1054 static const struct net_proto_family rfcomm_sock_family_ops = {
1055 	.family		= PF_BLUETOOTH,
1056 	.owner		= THIS_MODULE,
1057 	.create		= rfcomm_sock_create
1058 };
1059 
1060 int __init rfcomm_init_sockets(void)
1061 {
1062 	int err;
1063 
1064 	BUILD_BUG_ON(sizeof(struct sockaddr_rc) > sizeof(struct sockaddr));
1065 
1066 	err = proto_register(&rfcomm_proto, 0);
1067 	if (err < 0)
1068 		return err;
1069 
1070 	err = bt_sock_register(BTPROTO_RFCOMM, &rfcomm_sock_family_ops);
1071 	if (err < 0) {
1072 		BT_ERR("RFCOMM socket layer registration failed");
1073 		goto error;
1074 	}
1075 
1076 	err = bt_procfs_init(&init_net, "rfcomm", &rfcomm_sk_list, NULL);
1077 	if (err < 0) {
1078 		BT_ERR("Failed to create RFCOMM proc file");
1079 		bt_sock_unregister(BTPROTO_RFCOMM);
1080 		goto error;
1081 	}
1082 
1083 	BT_INFO("RFCOMM socket layer initialized");
1084 
1085 	if (IS_ERR_OR_NULL(bt_debugfs))
1086 		return 0;
1087 
1088 	rfcomm_sock_debugfs = debugfs_create_file("rfcomm", 0444,
1089 						  bt_debugfs, NULL,
1090 						  &rfcomm_sock_debugfs_fops);
1091 
1092 	return 0;
1093 
1094 error:
1095 	proto_unregister(&rfcomm_proto);
1096 	return err;
1097 }
1098 
1099 void __exit rfcomm_cleanup_sockets(void)
1100 {
1101 	bt_procfs_cleanup(&init_net, "rfcomm");
1102 
1103 	debugfs_remove(rfcomm_sock_debugfs);
1104 
1105 	bt_sock_unregister(BTPROTO_RFCOMM);
1106 
1107 	proto_unregister(&rfcomm_proto);
1108 }
1109