xref: /openbmc/linux/net/bluetooth/rfcomm/sock.c (revision 8fdff1dc)
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, skb->len);
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, 0);
88 	} else {
89 		if (d->state == BT_CONNECTED)
90 			rfcomm_session_getaddr(d->session, &bt_sk(sk)->src, NULL);
91 		sk->sk_state_change(sk);
92 	}
93 
94 	bh_unlock_sock(sk);
95 	local_irq_restore(flags);
96 
97 	if (parent && sock_flag(sk, SOCK_ZAPPED)) {
98 		/* We have to drop DLC lock here, otherwise
99 		 * rfcomm_sock_destruct() will dead lock. */
100 		rfcomm_dlc_unlock(d);
101 		rfcomm_sock_kill(sk);
102 		rfcomm_dlc_lock(d);
103 	}
104 }
105 
106 /* ---- Socket functions ---- */
107 static struct sock *__rfcomm_get_sock_by_addr(u8 channel, bdaddr_t *src)
108 {
109 	struct sock *sk = NULL;
110 	struct hlist_node *node;
111 
112 	sk_for_each(sk, node, &rfcomm_sk_list.head) {
113 		if (rfcomm_pi(sk)->channel == channel &&
114 				!bacmp(&bt_sk(sk)->src, src))
115 			break;
116 	}
117 
118 	return node ? sk : NULL;
119 }
120 
121 /* Find socket with channel and source bdaddr.
122  * Returns closest match.
123  */
124 static struct sock *rfcomm_get_sock_by_channel(int state, u8 channel, bdaddr_t *src)
125 {
126 	struct sock *sk = NULL, *sk1 = NULL;
127 	struct hlist_node *node;
128 
129 	read_lock(&rfcomm_sk_list.lock);
130 
131 	sk_for_each(sk, node, &rfcomm_sk_list.head) {
132 		if (state && sk->sk_state != state)
133 			continue;
134 
135 		if (rfcomm_pi(sk)->channel == channel) {
136 			/* Exact match. */
137 			if (!bacmp(&bt_sk(sk)->src, src))
138 				break;
139 
140 			/* Closest match */
141 			if (!bacmp(&bt_sk(sk)->src, BDADDR_ANY))
142 				sk1 = sk;
143 		}
144 	}
145 
146 	read_unlock(&rfcomm_sk_list.lock);
147 
148 	return node ? sk : sk1;
149 }
150 
151 static void rfcomm_sock_destruct(struct sock *sk)
152 {
153 	struct rfcomm_dlc *d = rfcomm_pi(sk)->dlc;
154 
155 	BT_DBG("sk %p dlc %p", sk, d);
156 
157 	skb_queue_purge(&sk->sk_receive_queue);
158 	skb_queue_purge(&sk->sk_write_queue);
159 
160 	rfcomm_dlc_lock(d);
161 	rfcomm_pi(sk)->dlc = NULL;
162 
163 	/* Detach DLC if it's owned by this socket */
164 	if (d->owner == sk)
165 		d->owner = NULL;
166 	rfcomm_dlc_unlock(d);
167 
168 	rfcomm_dlc_put(d);
169 }
170 
171 static void rfcomm_sock_cleanup_listen(struct sock *parent)
172 {
173 	struct sock *sk;
174 
175 	BT_DBG("parent %p", parent);
176 
177 	/* Close not yet accepted dlcs */
178 	while ((sk = bt_accept_dequeue(parent, NULL))) {
179 		rfcomm_sock_close(sk);
180 		rfcomm_sock_kill(sk);
181 	}
182 
183 	parent->sk_state  = BT_CLOSED;
184 	sock_set_flag(parent, SOCK_ZAPPED);
185 }
186 
187 /* Kill socket (only if zapped and orphan)
188  * Must be called on unlocked socket.
189  */
190 static void rfcomm_sock_kill(struct sock *sk)
191 {
192 	if (!sock_flag(sk, SOCK_ZAPPED) || sk->sk_socket)
193 		return;
194 
195 	BT_DBG("sk %p state %d refcnt %d", sk, sk->sk_state, atomic_read(&sk->sk_refcnt));
196 
197 	/* Kill poor orphan */
198 	bt_sock_unlink(&rfcomm_sk_list, sk);
199 	sock_set_flag(sk, SOCK_DEAD);
200 	sock_put(sk);
201 }
202 
203 static void __rfcomm_sock_close(struct sock *sk)
204 {
205 	struct rfcomm_dlc *d = rfcomm_pi(sk)->dlc;
206 
207 	BT_DBG("sk %p state %d socket %p", sk, sk->sk_state, sk->sk_socket);
208 
209 	switch (sk->sk_state) {
210 	case BT_LISTEN:
211 		rfcomm_sock_cleanup_listen(sk);
212 		break;
213 
214 	case BT_CONNECT:
215 	case BT_CONNECT2:
216 	case BT_CONFIG:
217 	case BT_CONNECTED:
218 		rfcomm_dlc_close(d, 0);
219 
220 	default:
221 		sock_set_flag(sk, SOCK_ZAPPED);
222 		break;
223 	}
224 }
225 
226 /* Close socket.
227  * Must be called on unlocked socket.
228  */
229 static void rfcomm_sock_close(struct sock *sk)
230 {
231 	lock_sock(sk);
232 	__rfcomm_sock_close(sk);
233 	release_sock(sk);
234 }
235 
236 static void rfcomm_sock_init(struct sock *sk, struct sock *parent)
237 {
238 	struct rfcomm_pinfo *pi = rfcomm_pi(sk);
239 
240 	BT_DBG("sk %p", sk);
241 
242 	if (parent) {
243 		sk->sk_type = parent->sk_type;
244 		pi->dlc->defer_setup = test_bit(BT_SK_DEFER_SETUP,
245 						&bt_sk(parent)->flags);
246 
247 		pi->sec_level = rfcomm_pi(parent)->sec_level;
248 		pi->role_switch = rfcomm_pi(parent)->role_switch;
249 
250 		security_sk_clone(parent, sk);
251 	} else {
252 		pi->dlc->defer_setup = 0;
253 
254 		pi->sec_level = BT_SECURITY_LOW;
255 		pi->role_switch = 0;
256 	}
257 
258 	pi->dlc->sec_level = pi->sec_level;
259 	pi->dlc->role_switch = pi->role_switch;
260 }
261 
262 static struct proto rfcomm_proto = {
263 	.name		= "RFCOMM",
264 	.owner		= THIS_MODULE,
265 	.obj_size	= sizeof(struct rfcomm_pinfo)
266 };
267 
268 static struct sock *rfcomm_sock_alloc(struct net *net, struct socket *sock, int proto, gfp_t prio)
269 {
270 	struct rfcomm_dlc *d;
271 	struct sock *sk;
272 
273 	sk = sk_alloc(net, PF_BLUETOOTH, prio, &rfcomm_proto);
274 	if (!sk)
275 		return NULL;
276 
277 	sock_init_data(sock, sk);
278 	INIT_LIST_HEAD(&bt_sk(sk)->accept_q);
279 
280 	d = rfcomm_dlc_alloc(prio);
281 	if (!d) {
282 		sk_free(sk);
283 		return NULL;
284 	}
285 
286 	d->data_ready   = rfcomm_sk_data_ready;
287 	d->state_change = rfcomm_sk_state_change;
288 
289 	rfcomm_pi(sk)->dlc = d;
290 	d->owner = sk;
291 
292 	sk->sk_destruct = rfcomm_sock_destruct;
293 	sk->sk_sndtimeo = RFCOMM_CONN_TIMEOUT;
294 
295 	sk->sk_sndbuf = RFCOMM_MAX_CREDITS * RFCOMM_DEFAULT_MTU * 10;
296 	sk->sk_rcvbuf = RFCOMM_MAX_CREDITS * RFCOMM_DEFAULT_MTU * 10;
297 
298 	sock_reset_flag(sk, SOCK_ZAPPED);
299 
300 	sk->sk_protocol = proto;
301 	sk->sk_state    = BT_OPEN;
302 
303 	bt_sock_link(&rfcomm_sk_list, sk);
304 
305 	BT_DBG("sk %p", sk);
306 	return sk;
307 }
308 
309 static int rfcomm_sock_create(struct net *net, struct socket *sock,
310 			      int protocol, int kern)
311 {
312 	struct sock *sk;
313 
314 	BT_DBG("sock %p", sock);
315 
316 	sock->state = SS_UNCONNECTED;
317 
318 	if (sock->type != SOCK_STREAM && sock->type != SOCK_RAW)
319 		return -ESOCKTNOSUPPORT;
320 
321 	sock->ops = &rfcomm_sock_ops;
322 
323 	sk = rfcomm_sock_alloc(net, sock, protocol, GFP_ATOMIC);
324 	if (!sk)
325 		return -ENOMEM;
326 
327 	rfcomm_sock_init(sk, NULL);
328 	return 0;
329 }
330 
331 static int rfcomm_sock_bind(struct socket *sock, struct sockaddr *addr, int addr_len)
332 {
333 	struct sockaddr_rc *sa = (struct sockaddr_rc *) addr;
334 	struct sock *sk = sock->sk;
335 	int err = 0;
336 
337 	BT_DBG("sk %p %pMR", sk, &sa->rc_bdaddr);
338 
339 	if (!addr || addr->sa_family != AF_BLUETOOTH)
340 		return -EINVAL;
341 
342 	lock_sock(sk);
343 
344 	if (sk->sk_state != BT_OPEN) {
345 		err = -EBADFD;
346 		goto done;
347 	}
348 
349 	if (sk->sk_type != SOCK_STREAM) {
350 		err = -EINVAL;
351 		goto done;
352 	}
353 
354 	write_lock(&rfcomm_sk_list.lock);
355 
356 	if (sa->rc_channel && __rfcomm_get_sock_by_addr(sa->rc_channel, &sa->rc_bdaddr)) {
357 		err = -EADDRINUSE;
358 	} else {
359 		/* Save source address */
360 		bacpy(&bt_sk(sk)->src, &sa->rc_bdaddr);
361 		rfcomm_pi(sk)->channel = sa->rc_channel;
362 		sk->sk_state = BT_BOUND;
363 	}
364 
365 	write_unlock(&rfcomm_sk_list.lock);
366 
367 done:
368 	release_sock(sk);
369 	return err;
370 }
371 
372 static int rfcomm_sock_connect(struct socket *sock, struct sockaddr *addr, int alen, int flags)
373 {
374 	struct sockaddr_rc *sa = (struct sockaddr_rc *) addr;
375 	struct sock *sk = sock->sk;
376 	struct rfcomm_dlc *d = rfcomm_pi(sk)->dlc;
377 	int err = 0;
378 
379 	BT_DBG("sk %p", sk);
380 
381 	if (alen < sizeof(struct sockaddr_rc) ||
382 	    addr->sa_family != AF_BLUETOOTH)
383 		return -EINVAL;
384 
385 	lock_sock(sk);
386 
387 	if (sk->sk_state != BT_OPEN && sk->sk_state != BT_BOUND) {
388 		err = -EBADFD;
389 		goto done;
390 	}
391 
392 	if (sk->sk_type != SOCK_STREAM) {
393 		err = -EINVAL;
394 		goto done;
395 	}
396 
397 	sk->sk_state = BT_CONNECT;
398 	bacpy(&bt_sk(sk)->dst, &sa->rc_bdaddr);
399 	rfcomm_pi(sk)->channel = sa->rc_channel;
400 
401 	d->sec_level = rfcomm_pi(sk)->sec_level;
402 	d->role_switch = rfcomm_pi(sk)->role_switch;
403 
404 	err = rfcomm_dlc_open(d, &bt_sk(sk)->src, &sa->rc_bdaddr, sa->rc_channel);
405 	if (!err)
406 		err = bt_sock_wait_state(sk, BT_CONNECTED,
407 				sock_sndtimeo(sk, flags & O_NONBLOCK));
408 
409 done:
410 	release_sock(sk);
411 	return err;
412 }
413 
414 static int rfcomm_sock_listen(struct socket *sock, int backlog)
415 {
416 	struct sock *sk = sock->sk;
417 	int err = 0;
418 
419 	BT_DBG("sk %p backlog %d", sk, backlog);
420 
421 	lock_sock(sk);
422 
423 	if (sk->sk_state != BT_BOUND) {
424 		err = -EBADFD;
425 		goto done;
426 	}
427 
428 	if (sk->sk_type != SOCK_STREAM) {
429 		err = -EINVAL;
430 		goto done;
431 	}
432 
433 	if (!rfcomm_pi(sk)->channel) {
434 		bdaddr_t *src = &bt_sk(sk)->src;
435 		u8 channel;
436 
437 		err = -EINVAL;
438 
439 		write_lock(&rfcomm_sk_list.lock);
440 
441 		for (channel = 1; channel < 31; channel++)
442 			if (!__rfcomm_get_sock_by_addr(channel, src)) {
443 				rfcomm_pi(sk)->channel = channel;
444 				err = 0;
445 				break;
446 			}
447 
448 		write_unlock(&rfcomm_sk_list.lock);
449 
450 		if (err < 0)
451 			goto done;
452 	}
453 
454 	sk->sk_max_ack_backlog = backlog;
455 	sk->sk_ack_backlog = 0;
456 	sk->sk_state = BT_LISTEN;
457 
458 done:
459 	release_sock(sk);
460 	return err;
461 }
462 
463 static int rfcomm_sock_accept(struct socket *sock, struct socket *newsock, int flags)
464 {
465 	DECLARE_WAITQUEUE(wait, current);
466 	struct sock *sk = sock->sk, *nsk;
467 	long timeo;
468 	int err = 0;
469 
470 	lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
471 
472 	if (sk->sk_type != SOCK_STREAM) {
473 		err = -EINVAL;
474 		goto done;
475 	}
476 
477 	timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
478 
479 	BT_DBG("sk %p timeo %ld", sk, timeo);
480 
481 	/* Wait for an incoming connection. (wake-one). */
482 	add_wait_queue_exclusive(sk_sleep(sk), &wait);
483 	while (1) {
484 		set_current_state(TASK_INTERRUPTIBLE);
485 
486 		if (sk->sk_state != BT_LISTEN) {
487 			err = -EBADFD;
488 			break;
489 		}
490 
491 		nsk = bt_accept_dequeue(sk, newsock);
492 		if (nsk)
493 			break;
494 
495 		if (!timeo) {
496 			err = -EAGAIN;
497 			break;
498 		}
499 
500 		if (signal_pending(current)) {
501 			err = sock_intr_errno(timeo);
502 			break;
503 		}
504 
505 		release_sock(sk);
506 		timeo = schedule_timeout(timeo);
507 		lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
508 	}
509 	__set_current_state(TASK_RUNNING);
510 	remove_wait_queue(sk_sleep(sk), &wait);
511 
512 	if (err)
513 		goto done;
514 
515 	newsock->state = SS_CONNECTED;
516 
517 	BT_DBG("new socket %p", nsk);
518 
519 done:
520 	release_sock(sk);
521 	return err;
522 }
523 
524 static int rfcomm_sock_getname(struct socket *sock, struct sockaddr *addr, int *len, int peer)
525 {
526 	struct sockaddr_rc *sa = (struct sockaddr_rc *) addr;
527 	struct sock *sk = sock->sk;
528 
529 	BT_DBG("sock %p, sk %p", sock, sk);
530 
531 	memset(sa, 0, sizeof(*sa));
532 	sa->rc_family  = AF_BLUETOOTH;
533 	sa->rc_channel = rfcomm_pi(sk)->channel;
534 	if (peer)
535 		bacpy(&sa->rc_bdaddr, &bt_sk(sk)->dst);
536 	else
537 		bacpy(&sa->rc_bdaddr, &bt_sk(sk)->src);
538 
539 	*len = sizeof(struct sockaddr_rc);
540 	return 0;
541 }
542 
543 static int rfcomm_sock_sendmsg(struct kiocb *iocb, struct socket *sock,
544 			       struct msghdr *msg, size_t len)
545 {
546 	struct sock *sk = sock->sk;
547 	struct rfcomm_dlc *d = rfcomm_pi(sk)->dlc;
548 	struct sk_buff *skb;
549 	int sent = 0;
550 
551 	if (test_bit(RFCOMM_DEFER_SETUP, &d->flags))
552 		return -ENOTCONN;
553 
554 	if (msg->msg_flags & MSG_OOB)
555 		return -EOPNOTSUPP;
556 
557 	if (sk->sk_shutdown & SEND_SHUTDOWN)
558 		return -EPIPE;
559 
560 	BT_DBG("sock %p, sk %p", sock, sk);
561 
562 	lock_sock(sk);
563 
564 	while (len) {
565 		size_t size = min_t(size_t, len, d->mtu);
566 		int err;
567 
568 		skb = sock_alloc_send_skb(sk, size + RFCOMM_SKB_RESERVE,
569 				msg->msg_flags & MSG_DONTWAIT, &err);
570 		if (!skb) {
571 			if (sent == 0)
572 				sent = err;
573 			break;
574 		}
575 		skb_reserve(skb, RFCOMM_SKB_HEAD_RESERVE);
576 
577 		err = memcpy_fromiovec(skb_put(skb, size), msg->msg_iov, size);
578 		if (err) {
579 			kfree_skb(skb);
580 			if (sent == 0)
581 				sent = err;
582 			break;
583 		}
584 
585 		skb->priority = sk->sk_priority;
586 
587 		err = rfcomm_dlc_send(d, skb);
588 		if (err < 0) {
589 			kfree_skb(skb);
590 			if (sent == 0)
591 				sent = err;
592 			break;
593 		}
594 
595 		sent += size;
596 		len  -= size;
597 	}
598 
599 	release_sock(sk);
600 
601 	return sent;
602 }
603 
604 static int rfcomm_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
605 			       struct msghdr *msg, size_t size, int flags)
606 {
607 	struct sock *sk = sock->sk;
608 	struct rfcomm_dlc *d = rfcomm_pi(sk)->dlc;
609 	int len;
610 
611 	if (test_and_clear_bit(RFCOMM_DEFER_SETUP, &d->flags)) {
612 		rfcomm_dlc_accept(d);
613 		return 0;
614 	}
615 
616 	len = bt_sock_stream_recvmsg(iocb, sock, msg, size, flags);
617 
618 	lock_sock(sk);
619 	if (!(flags & MSG_PEEK) && len > 0)
620 		atomic_sub(len, &sk->sk_rmem_alloc);
621 
622 	if (atomic_read(&sk->sk_rmem_alloc) <= (sk->sk_rcvbuf >> 2))
623 		rfcomm_dlc_unthrottle(rfcomm_pi(sk)->dlc);
624 	release_sock(sk);
625 
626 	return len;
627 }
628 
629 static int rfcomm_sock_setsockopt_old(struct socket *sock, int optname, char __user *optval, unsigned int optlen)
630 {
631 	struct sock *sk = sock->sk;
632 	int err = 0;
633 	u32 opt;
634 
635 	BT_DBG("sk %p", sk);
636 
637 	lock_sock(sk);
638 
639 	switch (optname) {
640 	case RFCOMM_LM:
641 		if (get_user(opt, (u32 __user *) optval)) {
642 			err = -EFAULT;
643 			break;
644 		}
645 
646 		if (opt & RFCOMM_LM_AUTH)
647 			rfcomm_pi(sk)->sec_level = BT_SECURITY_LOW;
648 		if (opt & RFCOMM_LM_ENCRYPT)
649 			rfcomm_pi(sk)->sec_level = BT_SECURITY_MEDIUM;
650 		if (opt & RFCOMM_LM_SECURE)
651 			rfcomm_pi(sk)->sec_level = BT_SECURITY_HIGH;
652 
653 		rfcomm_pi(sk)->role_switch = (opt & RFCOMM_LM_MASTER);
654 		break;
655 
656 	default:
657 		err = -ENOPROTOOPT;
658 		break;
659 	}
660 
661 	release_sock(sk);
662 	return err;
663 }
664 
665 static int rfcomm_sock_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen)
666 {
667 	struct sock *sk = sock->sk;
668 	struct bt_security sec;
669 	int err = 0;
670 	size_t len;
671 	u32 opt;
672 
673 	BT_DBG("sk %p", sk);
674 
675 	if (level == SOL_RFCOMM)
676 		return rfcomm_sock_setsockopt_old(sock, optname, optval, optlen);
677 
678 	if (level != SOL_BLUETOOTH)
679 		return -ENOPROTOOPT;
680 
681 	lock_sock(sk);
682 
683 	switch (optname) {
684 	case BT_SECURITY:
685 		if (sk->sk_type != SOCK_STREAM) {
686 			err = -EINVAL;
687 			break;
688 		}
689 
690 		sec.level = BT_SECURITY_LOW;
691 
692 		len = min_t(unsigned int, sizeof(sec), optlen);
693 		if (copy_from_user((char *) &sec, optval, len)) {
694 			err = -EFAULT;
695 			break;
696 		}
697 
698 		if (sec.level > BT_SECURITY_HIGH) {
699 			err = -EINVAL;
700 			break;
701 		}
702 
703 		rfcomm_pi(sk)->sec_level = sec.level;
704 		break;
705 
706 	case BT_DEFER_SETUP:
707 		if (sk->sk_state != BT_BOUND && sk->sk_state != BT_LISTEN) {
708 			err = -EINVAL;
709 			break;
710 		}
711 
712 		if (get_user(opt, (u32 __user *) optval)) {
713 			err = -EFAULT;
714 			break;
715 		}
716 
717 		if (opt)
718 			set_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags);
719 		else
720 			clear_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags);
721 
722 		break;
723 
724 	default:
725 		err = -ENOPROTOOPT;
726 		break;
727 	}
728 
729 	release_sock(sk);
730 	return err;
731 }
732 
733 static int rfcomm_sock_getsockopt_old(struct socket *sock, int optname, char __user *optval, int __user *optlen)
734 {
735 	struct sock *sk = sock->sk;
736 	struct rfcomm_conninfo cinfo;
737 	struct l2cap_conn *conn = l2cap_pi(sk)->chan->conn;
738 	int len, err = 0;
739 	u32 opt;
740 
741 	BT_DBG("sk %p", sk);
742 
743 	if (get_user(len, optlen))
744 		return -EFAULT;
745 
746 	lock_sock(sk);
747 
748 	switch (optname) {
749 	case RFCOMM_LM:
750 		switch (rfcomm_pi(sk)->sec_level) {
751 		case BT_SECURITY_LOW:
752 			opt = RFCOMM_LM_AUTH;
753 			break;
754 		case BT_SECURITY_MEDIUM:
755 			opt = RFCOMM_LM_AUTH | RFCOMM_LM_ENCRYPT;
756 			break;
757 		case BT_SECURITY_HIGH:
758 			opt = RFCOMM_LM_AUTH | RFCOMM_LM_ENCRYPT |
759 							RFCOMM_LM_SECURE;
760 			break;
761 		default:
762 			opt = 0;
763 			break;
764 		}
765 
766 		if (rfcomm_pi(sk)->role_switch)
767 			opt |= RFCOMM_LM_MASTER;
768 
769 		if (put_user(opt, (u32 __user *) optval))
770 			err = -EFAULT;
771 		break;
772 
773 	case RFCOMM_CONNINFO:
774 		if (sk->sk_state != BT_CONNECTED &&
775 					!rfcomm_pi(sk)->dlc->defer_setup) {
776 			err = -ENOTCONN;
777 			break;
778 		}
779 
780 		memset(&cinfo, 0, sizeof(cinfo));
781 		cinfo.hci_handle = conn->hcon->handle;
782 		memcpy(cinfo.dev_class, conn->hcon->dev_class, 3);
783 
784 		len = min_t(unsigned int, len, sizeof(cinfo));
785 		if (copy_to_user(optval, (char *) &cinfo, len))
786 			err = -EFAULT;
787 
788 		break;
789 
790 	default:
791 		err = -ENOPROTOOPT;
792 		break;
793 	}
794 
795 	release_sock(sk);
796 	return err;
797 }
798 
799 static int rfcomm_sock_getsockopt(struct socket *sock, int level, int optname, char __user *optval, int __user *optlen)
800 {
801 	struct sock *sk = sock->sk;
802 	struct bt_security sec;
803 	int len, err = 0;
804 
805 	BT_DBG("sk %p", sk);
806 
807 	if (level == SOL_RFCOMM)
808 		return rfcomm_sock_getsockopt_old(sock, optname, optval, optlen);
809 
810 	if (level != SOL_BLUETOOTH)
811 		return -ENOPROTOOPT;
812 
813 	if (get_user(len, optlen))
814 		return -EFAULT;
815 
816 	lock_sock(sk);
817 
818 	switch (optname) {
819 	case BT_SECURITY:
820 		if (sk->sk_type != SOCK_STREAM) {
821 			err = -EINVAL;
822 			break;
823 		}
824 
825 		sec.level = rfcomm_pi(sk)->sec_level;
826 		sec.key_size = 0;
827 
828 		len = min_t(unsigned int, len, sizeof(sec));
829 		if (copy_to_user(optval, (char *) &sec, len))
830 			err = -EFAULT;
831 
832 		break;
833 
834 	case BT_DEFER_SETUP:
835 		if (sk->sk_state != BT_BOUND && sk->sk_state != BT_LISTEN) {
836 			err = -EINVAL;
837 			break;
838 		}
839 
840 		if (put_user(test_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags),
841 			     (u32 __user *) optval))
842 			err = -EFAULT;
843 
844 		break;
845 
846 	default:
847 		err = -ENOPROTOOPT;
848 		break;
849 	}
850 
851 	release_sock(sk);
852 	return err;
853 }
854 
855 static int rfcomm_sock_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
856 {
857 	struct sock *sk __maybe_unused = sock->sk;
858 	int err;
859 
860 	BT_DBG("sk %p cmd %x arg %lx", sk, cmd, arg);
861 
862 	err = bt_sock_ioctl(sock, cmd, arg);
863 
864 	if (err == -ENOIOCTLCMD) {
865 #ifdef CONFIG_BT_RFCOMM_TTY
866 		lock_sock(sk);
867 		err = rfcomm_dev_ioctl(sk, cmd, (void __user *) arg);
868 		release_sock(sk);
869 #else
870 		err = -EOPNOTSUPP;
871 #endif
872 	}
873 
874 	return err;
875 }
876 
877 static int rfcomm_sock_shutdown(struct socket *sock, int how)
878 {
879 	struct sock *sk = sock->sk;
880 	int err = 0;
881 
882 	BT_DBG("sock %p, sk %p", sock, sk);
883 
884 	if (!sk)
885 		return 0;
886 
887 	lock_sock(sk);
888 	if (!sk->sk_shutdown) {
889 		sk->sk_shutdown = SHUTDOWN_MASK;
890 		__rfcomm_sock_close(sk);
891 
892 		if (sock_flag(sk, SOCK_LINGER) && sk->sk_lingertime)
893 			err = bt_sock_wait_state(sk, BT_CLOSED, sk->sk_lingertime);
894 	}
895 	release_sock(sk);
896 	return err;
897 }
898 
899 static int rfcomm_sock_release(struct socket *sock)
900 {
901 	struct sock *sk = sock->sk;
902 	int err;
903 
904 	BT_DBG("sock %p, sk %p", sock, sk);
905 
906 	if (!sk)
907 		return 0;
908 
909 	err = rfcomm_sock_shutdown(sock, 2);
910 
911 	sock_orphan(sk);
912 	rfcomm_sock_kill(sk);
913 	return err;
914 }
915 
916 /* ---- RFCOMM core layer callbacks ----
917  *
918  * called under rfcomm_lock()
919  */
920 int rfcomm_connect_ind(struct rfcomm_session *s, u8 channel, struct rfcomm_dlc **d)
921 {
922 	struct sock *sk, *parent;
923 	bdaddr_t src, dst;
924 	int result = 0;
925 
926 	BT_DBG("session %p channel %d", s, channel);
927 
928 	rfcomm_session_getaddr(s, &src, &dst);
929 
930 	/* Check if we have socket listening on channel */
931 	parent = rfcomm_get_sock_by_channel(BT_LISTEN, channel, &src);
932 	if (!parent)
933 		return 0;
934 
935 	bh_lock_sock(parent);
936 
937 	/* Check for backlog size */
938 	if (sk_acceptq_is_full(parent)) {
939 		BT_DBG("backlog full %d", parent->sk_ack_backlog);
940 		goto done;
941 	}
942 
943 	sk = rfcomm_sock_alloc(sock_net(parent), NULL, BTPROTO_RFCOMM, GFP_ATOMIC);
944 	if (!sk)
945 		goto done;
946 
947 	bt_sock_reclassify_lock(sk, BTPROTO_RFCOMM);
948 
949 	rfcomm_sock_init(sk, parent);
950 	bacpy(&bt_sk(sk)->src, &src);
951 	bacpy(&bt_sk(sk)->dst, &dst);
952 	rfcomm_pi(sk)->channel = channel;
953 
954 	sk->sk_state = BT_CONFIG;
955 	bt_accept_enqueue(parent, sk);
956 
957 	/* Accept connection and return socket DLC */
958 	*d = rfcomm_pi(sk)->dlc;
959 	result = 1;
960 
961 done:
962 	bh_unlock_sock(parent);
963 
964 	if (test_bit(BT_SK_DEFER_SETUP, &bt_sk(parent)->flags))
965 		parent->sk_state_change(parent);
966 
967 	return result;
968 }
969 
970 static int rfcomm_sock_debugfs_show(struct seq_file *f, void *p)
971 {
972 	struct sock *sk;
973 	struct hlist_node *node;
974 
975 	read_lock(&rfcomm_sk_list.lock);
976 
977 	sk_for_each(sk, node, &rfcomm_sk_list.head) {
978 		seq_printf(f, "%pMR %pMR %d %d\n",
979 			   &bt_sk(sk)->src, &bt_sk(sk)->dst,
980 			   sk->sk_state, rfcomm_pi(sk)->channel);
981 	}
982 
983 	read_unlock(&rfcomm_sk_list.lock);
984 
985 	return 0;
986 }
987 
988 static int rfcomm_sock_debugfs_open(struct inode *inode, struct file *file)
989 {
990 	return single_open(file, rfcomm_sock_debugfs_show, inode->i_private);
991 }
992 
993 static const struct file_operations rfcomm_sock_debugfs_fops = {
994 	.open		= rfcomm_sock_debugfs_open,
995 	.read		= seq_read,
996 	.llseek		= seq_lseek,
997 	.release	= single_release,
998 };
999 
1000 static struct dentry *rfcomm_sock_debugfs;
1001 
1002 static const struct proto_ops rfcomm_sock_ops = {
1003 	.family		= PF_BLUETOOTH,
1004 	.owner		= THIS_MODULE,
1005 	.release	= rfcomm_sock_release,
1006 	.bind		= rfcomm_sock_bind,
1007 	.connect	= rfcomm_sock_connect,
1008 	.listen		= rfcomm_sock_listen,
1009 	.accept		= rfcomm_sock_accept,
1010 	.getname	= rfcomm_sock_getname,
1011 	.sendmsg	= rfcomm_sock_sendmsg,
1012 	.recvmsg	= rfcomm_sock_recvmsg,
1013 	.shutdown	= rfcomm_sock_shutdown,
1014 	.setsockopt	= rfcomm_sock_setsockopt,
1015 	.getsockopt	= rfcomm_sock_getsockopt,
1016 	.ioctl		= rfcomm_sock_ioctl,
1017 	.poll		= bt_sock_poll,
1018 	.socketpair	= sock_no_socketpair,
1019 	.mmap		= sock_no_mmap
1020 };
1021 
1022 static const struct net_proto_family rfcomm_sock_family_ops = {
1023 	.family		= PF_BLUETOOTH,
1024 	.owner		= THIS_MODULE,
1025 	.create		= rfcomm_sock_create
1026 };
1027 
1028 int __init rfcomm_init_sockets(void)
1029 {
1030 	int err;
1031 
1032 	err = proto_register(&rfcomm_proto, 0);
1033 	if (err < 0)
1034 		return err;
1035 
1036 	err = bt_sock_register(BTPROTO_RFCOMM, &rfcomm_sock_family_ops);
1037 	if (err < 0) {
1038 		BT_ERR("RFCOMM socket layer registration failed");
1039 		goto error;
1040 	}
1041 
1042 	err = bt_procfs_init(THIS_MODULE, &init_net, "rfcomm", &rfcomm_sk_list, NULL);
1043 	if (err < 0) {
1044 		BT_ERR("Failed to create RFCOMM proc file");
1045 		bt_sock_unregister(BTPROTO_RFCOMM);
1046 		goto error;
1047 	}
1048 
1049 	if (bt_debugfs) {
1050 		rfcomm_sock_debugfs = debugfs_create_file("rfcomm", 0444,
1051 				bt_debugfs, NULL, &rfcomm_sock_debugfs_fops);
1052 		if (!rfcomm_sock_debugfs)
1053 			BT_ERR("Failed to create RFCOMM debug file");
1054 	}
1055 
1056 	BT_INFO("RFCOMM socket layer initialized");
1057 
1058 	return 0;
1059 
1060 error:
1061 	proto_unregister(&rfcomm_proto);
1062 	return err;
1063 }
1064 
1065 void __exit rfcomm_cleanup_sockets(void)
1066 {
1067 	bt_procfs_cleanup(&init_net, "rfcomm");
1068 
1069 	debugfs_remove(rfcomm_sock_debugfs);
1070 
1071 	if (bt_sock_unregister(BTPROTO_RFCOMM) < 0)
1072 		BT_ERR("RFCOMM socket layer unregistration failed");
1073 
1074 	proto_unregister(&rfcomm_proto);
1075 }
1076