xref: /openbmc/linux/net/bluetooth/rfcomm/sock.c (revision 9344dade)
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 
111 	sk_for_each(sk, &rfcomm_sk_list.head) {
112 		if (rfcomm_pi(sk)->channel == channel &&
113 				!bacmp(&bt_sk(sk)->src, src))
114 			break;
115 	}
116 
117 	return sk ? sk : NULL;
118 }
119 
120 /* Find socket with channel and source bdaddr.
121  * Returns closest match.
122  */
123 static struct sock *rfcomm_get_sock_by_channel(int state, u8 channel, bdaddr_t *src)
124 {
125 	struct sock *sk = NULL, *sk1 = NULL;
126 
127 	read_lock(&rfcomm_sk_list.lock);
128 
129 	sk_for_each(sk, &rfcomm_sk_list.head) {
130 		if (state && sk->sk_state != state)
131 			continue;
132 
133 		if (rfcomm_pi(sk)->channel == channel) {
134 			/* Exact match. */
135 			if (!bacmp(&bt_sk(sk)->src, src))
136 				break;
137 
138 			/* Closest match */
139 			if (!bacmp(&bt_sk(sk)->src, BDADDR_ANY))
140 				sk1 = sk;
141 		}
142 	}
143 
144 	read_unlock(&rfcomm_sk_list.lock);
145 
146 	return sk ? sk : sk1;
147 }
148 
149 static void rfcomm_sock_destruct(struct sock *sk)
150 {
151 	struct rfcomm_dlc *d = rfcomm_pi(sk)->dlc;
152 
153 	BT_DBG("sk %p dlc %p", sk, d);
154 
155 	skb_queue_purge(&sk->sk_receive_queue);
156 	skb_queue_purge(&sk->sk_write_queue);
157 
158 	rfcomm_dlc_lock(d);
159 	rfcomm_pi(sk)->dlc = NULL;
160 
161 	/* Detach DLC if it's owned by this socket */
162 	if (d->owner == sk)
163 		d->owner = NULL;
164 	rfcomm_dlc_unlock(d);
165 
166 	rfcomm_dlc_put(d);
167 }
168 
169 static void rfcomm_sock_cleanup_listen(struct sock *parent)
170 {
171 	struct sock *sk;
172 
173 	BT_DBG("parent %p", parent);
174 
175 	/* Close not yet accepted dlcs */
176 	while ((sk = bt_accept_dequeue(parent, NULL))) {
177 		rfcomm_sock_close(sk);
178 		rfcomm_sock_kill(sk);
179 	}
180 
181 	parent->sk_state  = BT_CLOSED;
182 	sock_set_flag(parent, SOCK_ZAPPED);
183 }
184 
185 /* Kill socket (only if zapped and orphan)
186  * Must be called on unlocked socket.
187  */
188 static void rfcomm_sock_kill(struct sock *sk)
189 {
190 	if (!sock_flag(sk, SOCK_ZAPPED) || sk->sk_socket)
191 		return;
192 
193 	BT_DBG("sk %p state %d refcnt %d", sk, sk->sk_state, atomic_read(&sk->sk_refcnt));
194 
195 	/* Kill poor orphan */
196 	bt_sock_unlink(&rfcomm_sk_list, sk);
197 	sock_set_flag(sk, SOCK_DEAD);
198 	sock_put(sk);
199 }
200 
201 static void __rfcomm_sock_close(struct sock *sk)
202 {
203 	struct rfcomm_dlc *d = rfcomm_pi(sk)->dlc;
204 
205 	BT_DBG("sk %p state %d socket %p", sk, sk->sk_state, sk->sk_socket);
206 
207 	switch (sk->sk_state) {
208 	case BT_LISTEN:
209 		rfcomm_sock_cleanup_listen(sk);
210 		break;
211 
212 	case BT_CONNECT:
213 	case BT_CONNECT2:
214 	case BT_CONFIG:
215 	case BT_CONNECTED:
216 		rfcomm_dlc_close(d, 0);
217 
218 	default:
219 		sock_set_flag(sk, SOCK_ZAPPED);
220 		break;
221 	}
222 }
223 
224 /* Close socket.
225  * Must be called on unlocked socket.
226  */
227 static void rfcomm_sock_close(struct sock *sk)
228 {
229 	lock_sock(sk);
230 	__rfcomm_sock_close(sk);
231 	release_sock(sk);
232 }
233 
234 static void rfcomm_sock_init(struct sock *sk, struct sock *parent)
235 {
236 	struct rfcomm_pinfo *pi = rfcomm_pi(sk);
237 
238 	BT_DBG("sk %p", sk);
239 
240 	if (parent) {
241 		sk->sk_type = parent->sk_type;
242 		pi->dlc->defer_setup = test_bit(BT_SK_DEFER_SETUP,
243 						&bt_sk(parent)->flags);
244 
245 		pi->sec_level = rfcomm_pi(parent)->sec_level;
246 		pi->role_switch = rfcomm_pi(parent)->role_switch;
247 
248 		security_sk_clone(parent, sk);
249 	} else {
250 		pi->dlc->defer_setup = 0;
251 
252 		pi->sec_level = BT_SECURITY_LOW;
253 		pi->role_switch = 0;
254 	}
255 
256 	pi->dlc->sec_level = pi->sec_level;
257 	pi->dlc->role_switch = pi->role_switch;
258 }
259 
260 static struct proto rfcomm_proto = {
261 	.name		= "RFCOMM",
262 	.owner		= THIS_MODULE,
263 	.obj_size	= sizeof(struct rfcomm_pinfo)
264 };
265 
266 static struct sock *rfcomm_sock_alloc(struct net *net, struct socket *sock, int proto, gfp_t prio)
267 {
268 	struct rfcomm_dlc *d;
269 	struct sock *sk;
270 
271 	sk = sk_alloc(net, PF_BLUETOOTH, prio, &rfcomm_proto);
272 	if (!sk)
273 		return NULL;
274 
275 	sock_init_data(sock, sk);
276 	INIT_LIST_HEAD(&bt_sk(sk)->accept_q);
277 
278 	d = rfcomm_dlc_alloc(prio);
279 	if (!d) {
280 		sk_free(sk);
281 		return NULL;
282 	}
283 
284 	d->data_ready   = rfcomm_sk_data_ready;
285 	d->state_change = rfcomm_sk_state_change;
286 
287 	rfcomm_pi(sk)->dlc = d;
288 	d->owner = sk;
289 
290 	sk->sk_destruct = rfcomm_sock_destruct;
291 	sk->sk_sndtimeo = RFCOMM_CONN_TIMEOUT;
292 
293 	sk->sk_sndbuf = RFCOMM_MAX_CREDITS * RFCOMM_DEFAULT_MTU * 10;
294 	sk->sk_rcvbuf = RFCOMM_MAX_CREDITS * RFCOMM_DEFAULT_MTU * 10;
295 
296 	sock_reset_flag(sk, SOCK_ZAPPED);
297 
298 	sk->sk_protocol = proto;
299 	sk->sk_state    = BT_OPEN;
300 
301 	bt_sock_link(&rfcomm_sk_list, sk);
302 
303 	BT_DBG("sk %p", sk);
304 	return sk;
305 }
306 
307 static int rfcomm_sock_create(struct net *net, struct socket *sock,
308 			      int protocol, int kern)
309 {
310 	struct sock *sk;
311 
312 	BT_DBG("sock %p", sock);
313 
314 	sock->state = SS_UNCONNECTED;
315 
316 	if (sock->type != SOCK_STREAM && sock->type != SOCK_RAW)
317 		return -ESOCKTNOSUPPORT;
318 
319 	sock->ops = &rfcomm_sock_ops;
320 
321 	sk = rfcomm_sock_alloc(net, sock, protocol, GFP_ATOMIC);
322 	if (!sk)
323 		return -ENOMEM;
324 
325 	rfcomm_sock_init(sk, NULL);
326 	return 0;
327 }
328 
329 static int rfcomm_sock_bind(struct socket *sock, struct sockaddr *addr, int addr_len)
330 {
331 	struct sockaddr_rc *sa = (struct sockaddr_rc *) addr;
332 	struct sock *sk = sock->sk;
333 	int err = 0;
334 
335 	BT_DBG("sk %p %pMR", sk, &sa->rc_bdaddr);
336 
337 	if (!addr || addr->sa_family != AF_BLUETOOTH)
338 		return -EINVAL;
339 
340 	lock_sock(sk);
341 
342 	if (sk->sk_state != BT_OPEN) {
343 		err = -EBADFD;
344 		goto done;
345 	}
346 
347 	if (sk->sk_type != SOCK_STREAM) {
348 		err = -EINVAL;
349 		goto done;
350 	}
351 
352 	write_lock(&rfcomm_sk_list.lock);
353 
354 	if (sa->rc_channel && __rfcomm_get_sock_by_addr(sa->rc_channel, &sa->rc_bdaddr)) {
355 		err = -EADDRINUSE;
356 	} else {
357 		/* Save source address */
358 		bacpy(&bt_sk(sk)->src, &sa->rc_bdaddr);
359 		rfcomm_pi(sk)->channel = sa->rc_channel;
360 		sk->sk_state = BT_BOUND;
361 	}
362 
363 	write_unlock(&rfcomm_sk_list.lock);
364 
365 done:
366 	release_sock(sk);
367 	return err;
368 }
369 
370 static int rfcomm_sock_connect(struct socket *sock, struct sockaddr *addr, int alen, int flags)
371 {
372 	struct sockaddr_rc *sa = (struct sockaddr_rc *) addr;
373 	struct sock *sk = sock->sk;
374 	struct rfcomm_dlc *d = rfcomm_pi(sk)->dlc;
375 	int err = 0;
376 
377 	BT_DBG("sk %p", sk);
378 
379 	if (alen < sizeof(struct sockaddr_rc) ||
380 	    addr->sa_family != AF_BLUETOOTH)
381 		return -EINVAL;
382 
383 	lock_sock(sk);
384 
385 	if (sk->sk_state != BT_OPEN && sk->sk_state != BT_BOUND) {
386 		err = -EBADFD;
387 		goto done;
388 	}
389 
390 	if (sk->sk_type != SOCK_STREAM) {
391 		err = -EINVAL;
392 		goto done;
393 	}
394 
395 	sk->sk_state = BT_CONNECT;
396 	bacpy(&bt_sk(sk)->dst, &sa->rc_bdaddr);
397 	rfcomm_pi(sk)->channel = sa->rc_channel;
398 
399 	d->sec_level = rfcomm_pi(sk)->sec_level;
400 	d->role_switch = rfcomm_pi(sk)->role_switch;
401 
402 	err = rfcomm_dlc_open(d, &bt_sk(sk)->src, &sa->rc_bdaddr, sa->rc_channel);
403 	if (!err)
404 		err = bt_sock_wait_state(sk, BT_CONNECTED,
405 				sock_sndtimeo(sk, flags & O_NONBLOCK));
406 
407 done:
408 	release_sock(sk);
409 	return err;
410 }
411 
412 static int rfcomm_sock_listen(struct socket *sock, int backlog)
413 {
414 	struct sock *sk = sock->sk;
415 	int err = 0;
416 
417 	BT_DBG("sk %p backlog %d", sk, backlog);
418 
419 	lock_sock(sk);
420 
421 	if (sk->sk_state != BT_BOUND) {
422 		err = -EBADFD;
423 		goto done;
424 	}
425 
426 	if (sk->sk_type != SOCK_STREAM) {
427 		err = -EINVAL;
428 		goto done;
429 	}
430 
431 	if (!rfcomm_pi(sk)->channel) {
432 		bdaddr_t *src = &bt_sk(sk)->src;
433 		u8 channel;
434 
435 		err = -EINVAL;
436 
437 		write_lock(&rfcomm_sk_list.lock);
438 
439 		for (channel = 1; channel < 31; channel++)
440 			if (!__rfcomm_get_sock_by_addr(channel, src)) {
441 				rfcomm_pi(sk)->channel = channel;
442 				err = 0;
443 				break;
444 			}
445 
446 		write_unlock(&rfcomm_sk_list.lock);
447 
448 		if (err < 0)
449 			goto done;
450 	}
451 
452 	sk->sk_max_ack_backlog = backlog;
453 	sk->sk_ack_backlog = 0;
454 	sk->sk_state = BT_LISTEN;
455 
456 done:
457 	release_sock(sk);
458 	return err;
459 }
460 
461 static int rfcomm_sock_accept(struct socket *sock, struct socket *newsock, int flags)
462 {
463 	DECLARE_WAITQUEUE(wait, current);
464 	struct sock *sk = sock->sk, *nsk;
465 	long timeo;
466 	int err = 0;
467 
468 	lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
469 
470 	if (sk->sk_type != SOCK_STREAM) {
471 		err = -EINVAL;
472 		goto done;
473 	}
474 
475 	timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
476 
477 	BT_DBG("sk %p timeo %ld", sk, timeo);
478 
479 	/* Wait for an incoming connection. (wake-one). */
480 	add_wait_queue_exclusive(sk_sleep(sk), &wait);
481 	while (1) {
482 		set_current_state(TASK_INTERRUPTIBLE);
483 
484 		if (sk->sk_state != BT_LISTEN) {
485 			err = -EBADFD;
486 			break;
487 		}
488 
489 		nsk = bt_accept_dequeue(sk, newsock);
490 		if (nsk)
491 			break;
492 
493 		if (!timeo) {
494 			err = -EAGAIN;
495 			break;
496 		}
497 
498 		if (signal_pending(current)) {
499 			err = sock_intr_errno(timeo);
500 			break;
501 		}
502 
503 		release_sock(sk);
504 		timeo = schedule_timeout(timeo);
505 		lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
506 	}
507 	__set_current_state(TASK_RUNNING);
508 	remove_wait_queue(sk_sleep(sk), &wait);
509 
510 	if (err)
511 		goto done;
512 
513 	newsock->state = SS_CONNECTED;
514 
515 	BT_DBG("new socket %p", nsk);
516 
517 done:
518 	release_sock(sk);
519 	return err;
520 }
521 
522 static int rfcomm_sock_getname(struct socket *sock, struct sockaddr *addr, int *len, int peer)
523 {
524 	struct sockaddr_rc *sa = (struct sockaddr_rc *) addr;
525 	struct sock *sk = sock->sk;
526 
527 	BT_DBG("sock %p, sk %p", sock, sk);
528 
529 	memset(sa, 0, sizeof(*sa));
530 	sa->rc_family  = AF_BLUETOOTH;
531 	sa->rc_channel = rfcomm_pi(sk)->channel;
532 	if (peer)
533 		bacpy(&sa->rc_bdaddr, &bt_sk(sk)->dst);
534 	else
535 		bacpy(&sa->rc_bdaddr, &bt_sk(sk)->src);
536 
537 	*len = sizeof(struct sockaddr_rc);
538 	return 0;
539 }
540 
541 static int rfcomm_sock_sendmsg(struct kiocb *iocb, struct socket *sock,
542 			       struct msghdr *msg, size_t len)
543 {
544 	struct sock *sk = sock->sk;
545 	struct rfcomm_dlc *d = rfcomm_pi(sk)->dlc;
546 	struct sk_buff *skb;
547 	int sent = 0;
548 
549 	if (test_bit(RFCOMM_DEFER_SETUP, &d->flags))
550 		return -ENOTCONN;
551 
552 	if (msg->msg_flags & MSG_OOB)
553 		return -EOPNOTSUPP;
554 
555 	if (sk->sk_shutdown & SEND_SHUTDOWN)
556 		return -EPIPE;
557 
558 	BT_DBG("sock %p, sk %p", sock, sk);
559 
560 	lock_sock(sk);
561 
562 	while (len) {
563 		size_t size = min_t(size_t, len, d->mtu);
564 		int err;
565 
566 		skb = sock_alloc_send_skb(sk, size + RFCOMM_SKB_RESERVE,
567 				msg->msg_flags & MSG_DONTWAIT, &err);
568 		if (!skb) {
569 			if (sent == 0)
570 				sent = err;
571 			break;
572 		}
573 		skb_reserve(skb, RFCOMM_SKB_HEAD_RESERVE);
574 
575 		err = memcpy_fromiovec(skb_put(skb, size), msg->msg_iov, size);
576 		if (err) {
577 			kfree_skb(skb);
578 			if (sent == 0)
579 				sent = err;
580 			break;
581 		}
582 
583 		skb->priority = sk->sk_priority;
584 
585 		err = rfcomm_dlc_send(d, skb);
586 		if (err < 0) {
587 			kfree_skb(skb);
588 			if (sent == 0)
589 				sent = err;
590 			break;
591 		}
592 
593 		sent += size;
594 		len  -= size;
595 	}
596 
597 	release_sock(sk);
598 
599 	return sent;
600 }
601 
602 static int rfcomm_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
603 			       struct msghdr *msg, size_t size, int flags)
604 {
605 	struct sock *sk = sock->sk;
606 	struct rfcomm_dlc *d = rfcomm_pi(sk)->dlc;
607 	int len;
608 
609 	if (test_and_clear_bit(RFCOMM_DEFER_SETUP, &d->flags)) {
610 		rfcomm_dlc_accept(d);
611 		msg->msg_namelen = 0;
612 		return 0;
613 	}
614 
615 	len = bt_sock_stream_recvmsg(iocb, sock, msg, size, flags);
616 
617 	lock_sock(sk);
618 	if (!(flags & MSG_PEEK) && len > 0)
619 		atomic_sub(len, &sk->sk_rmem_alloc);
620 
621 	if (atomic_read(&sk->sk_rmem_alloc) <= (sk->sk_rcvbuf >> 2))
622 		rfcomm_dlc_unthrottle(rfcomm_pi(sk)->dlc);
623 	release_sock(sk);
624 
625 	return len;
626 }
627 
628 static int rfcomm_sock_setsockopt_old(struct socket *sock, int optname, char __user *optval, unsigned int optlen)
629 {
630 	struct sock *sk = sock->sk;
631 	int err = 0;
632 	u32 opt;
633 
634 	BT_DBG("sk %p", sk);
635 
636 	lock_sock(sk);
637 
638 	switch (optname) {
639 	case RFCOMM_LM:
640 		if (get_user(opt, (u32 __user *) optval)) {
641 			err = -EFAULT;
642 			break;
643 		}
644 
645 		if (opt & RFCOMM_LM_AUTH)
646 			rfcomm_pi(sk)->sec_level = BT_SECURITY_LOW;
647 		if (opt & RFCOMM_LM_ENCRYPT)
648 			rfcomm_pi(sk)->sec_level = BT_SECURITY_MEDIUM;
649 		if (opt & RFCOMM_LM_SECURE)
650 			rfcomm_pi(sk)->sec_level = BT_SECURITY_HIGH;
651 
652 		rfcomm_pi(sk)->role_switch = (opt & RFCOMM_LM_MASTER);
653 		break;
654 
655 	default:
656 		err = -ENOPROTOOPT;
657 		break;
658 	}
659 
660 	release_sock(sk);
661 	return err;
662 }
663 
664 static int rfcomm_sock_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen)
665 {
666 	struct sock *sk = sock->sk;
667 	struct bt_security sec;
668 	int err = 0;
669 	size_t len;
670 	u32 opt;
671 
672 	BT_DBG("sk %p", sk);
673 
674 	if (level == SOL_RFCOMM)
675 		return rfcomm_sock_setsockopt_old(sock, optname, optval, optlen);
676 
677 	if (level != SOL_BLUETOOTH)
678 		return -ENOPROTOOPT;
679 
680 	lock_sock(sk);
681 
682 	switch (optname) {
683 	case BT_SECURITY:
684 		if (sk->sk_type != SOCK_STREAM) {
685 			err = -EINVAL;
686 			break;
687 		}
688 
689 		sec.level = BT_SECURITY_LOW;
690 
691 		len = min_t(unsigned int, sizeof(sec), optlen);
692 		if (copy_from_user((char *) &sec, optval, len)) {
693 			err = -EFAULT;
694 			break;
695 		}
696 
697 		if (sec.level > BT_SECURITY_HIGH) {
698 			err = -EINVAL;
699 			break;
700 		}
701 
702 		rfcomm_pi(sk)->sec_level = sec.level;
703 		break;
704 
705 	case BT_DEFER_SETUP:
706 		if (sk->sk_state != BT_BOUND && sk->sk_state != BT_LISTEN) {
707 			err = -EINVAL;
708 			break;
709 		}
710 
711 		if (get_user(opt, (u32 __user *) optval)) {
712 			err = -EFAULT;
713 			break;
714 		}
715 
716 		if (opt)
717 			set_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags);
718 		else
719 			clear_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags);
720 
721 		break;
722 
723 	default:
724 		err = -ENOPROTOOPT;
725 		break;
726 	}
727 
728 	release_sock(sk);
729 	return err;
730 }
731 
732 static int rfcomm_sock_getsockopt_old(struct socket *sock, int optname, char __user *optval, int __user *optlen)
733 {
734 	struct sock *sk = sock->sk;
735 	struct rfcomm_conninfo cinfo;
736 	struct l2cap_conn *conn = l2cap_pi(sk)->chan->conn;
737 	int len, err = 0;
738 	u32 opt;
739 
740 	BT_DBG("sk %p", sk);
741 
742 	if (get_user(len, optlen))
743 		return -EFAULT;
744 
745 	lock_sock(sk);
746 
747 	switch (optname) {
748 	case RFCOMM_LM:
749 		switch (rfcomm_pi(sk)->sec_level) {
750 		case BT_SECURITY_LOW:
751 			opt = RFCOMM_LM_AUTH;
752 			break;
753 		case BT_SECURITY_MEDIUM:
754 			opt = RFCOMM_LM_AUTH | RFCOMM_LM_ENCRYPT;
755 			break;
756 		case BT_SECURITY_HIGH:
757 			opt = RFCOMM_LM_AUTH | RFCOMM_LM_ENCRYPT |
758 							RFCOMM_LM_SECURE;
759 			break;
760 		default:
761 			opt = 0;
762 			break;
763 		}
764 
765 		if (rfcomm_pi(sk)->role_switch)
766 			opt |= RFCOMM_LM_MASTER;
767 
768 		if (put_user(opt, (u32 __user *) optval))
769 			err = -EFAULT;
770 		break;
771 
772 	case RFCOMM_CONNINFO:
773 		if (sk->sk_state != BT_CONNECTED &&
774 					!rfcomm_pi(sk)->dlc->defer_setup) {
775 			err = -ENOTCONN;
776 			break;
777 		}
778 
779 		memset(&cinfo, 0, sizeof(cinfo));
780 		cinfo.hci_handle = conn->hcon->handle;
781 		memcpy(cinfo.dev_class, conn->hcon->dev_class, 3);
782 
783 		len = min_t(unsigned int, len, sizeof(cinfo));
784 		if (copy_to_user(optval, (char *) &cinfo, len))
785 			err = -EFAULT;
786 
787 		break;
788 
789 	default:
790 		err = -ENOPROTOOPT;
791 		break;
792 	}
793 
794 	release_sock(sk);
795 	return err;
796 }
797 
798 static int rfcomm_sock_getsockopt(struct socket *sock, int level, int optname, char __user *optval, int __user *optlen)
799 {
800 	struct sock *sk = sock->sk;
801 	struct bt_security sec;
802 	int len, err = 0;
803 
804 	BT_DBG("sk %p", sk);
805 
806 	if (level == SOL_RFCOMM)
807 		return rfcomm_sock_getsockopt_old(sock, optname, optval, optlen);
808 
809 	if (level != SOL_BLUETOOTH)
810 		return -ENOPROTOOPT;
811 
812 	if (get_user(len, optlen))
813 		return -EFAULT;
814 
815 	lock_sock(sk);
816 
817 	switch (optname) {
818 	case BT_SECURITY:
819 		if (sk->sk_type != SOCK_STREAM) {
820 			err = -EINVAL;
821 			break;
822 		}
823 
824 		sec.level = rfcomm_pi(sk)->sec_level;
825 		sec.key_size = 0;
826 
827 		len = min_t(unsigned int, len, sizeof(sec));
828 		if (copy_to_user(optval, (char *) &sec, len))
829 			err = -EFAULT;
830 
831 		break;
832 
833 	case BT_DEFER_SETUP:
834 		if (sk->sk_state != BT_BOUND && sk->sk_state != BT_LISTEN) {
835 			err = -EINVAL;
836 			break;
837 		}
838 
839 		if (put_user(test_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags),
840 			     (u32 __user *) optval))
841 			err = -EFAULT;
842 
843 		break;
844 
845 	default:
846 		err = -ENOPROTOOPT;
847 		break;
848 	}
849 
850 	release_sock(sk);
851 	return err;
852 }
853 
854 static int rfcomm_sock_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
855 {
856 	struct sock *sk __maybe_unused = sock->sk;
857 	int err;
858 
859 	BT_DBG("sk %p cmd %x arg %lx", sk, cmd, arg);
860 
861 	err = bt_sock_ioctl(sock, cmd, arg);
862 
863 	if (err == -ENOIOCTLCMD) {
864 #ifdef CONFIG_BT_RFCOMM_TTY
865 		lock_sock(sk);
866 		err = rfcomm_dev_ioctl(sk, cmd, (void __user *) arg);
867 		release_sock(sk);
868 #else
869 		err = -EOPNOTSUPP;
870 #endif
871 	}
872 
873 	return err;
874 }
875 
876 static int rfcomm_sock_shutdown(struct socket *sock, int how)
877 {
878 	struct sock *sk = sock->sk;
879 	int err = 0;
880 
881 	BT_DBG("sock %p, sk %p", sock, sk);
882 
883 	if (!sk)
884 		return 0;
885 
886 	lock_sock(sk);
887 	if (!sk->sk_shutdown) {
888 		sk->sk_shutdown = SHUTDOWN_MASK;
889 		__rfcomm_sock_close(sk);
890 
891 		if (sock_flag(sk, SOCK_LINGER) && sk->sk_lingertime)
892 			err = bt_sock_wait_state(sk, BT_CLOSED, sk->sk_lingertime);
893 	}
894 	release_sock(sk);
895 	return err;
896 }
897 
898 static int rfcomm_sock_release(struct socket *sock)
899 {
900 	struct sock *sk = sock->sk;
901 	int err;
902 
903 	BT_DBG("sock %p, sk %p", sock, sk);
904 
905 	if (!sk)
906 		return 0;
907 
908 	err = rfcomm_sock_shutdown(sock, 2);
909 
910 	sock_orphan(sk);
911 	rfcomm_sock_kill(sk);
912 	return err;
913 }
914 
915 /* ---- RFCOMM core layer callbacks ----
916  *
917  * called under rfcomm_lock()
918  */
919 int rfcomm_connect_ind(struct rfcomm_session *s, u8 channel, struct rfcomm_dlc **d)
920 {
921 	struct sock *sk, *parent;
922 	bdaddr_t src, dst;
923 	int result = 0;
924 
925 	BT_DBG("session %p channel %d", s, channel);
926 
927 	rfcomm_session_getaddr(s, &src, &dst);
928 
929 	/* Check if we have socket listening on channel */
930 	parent = rfcomm_get_sock_by_channel(BT_LISTEN, channel, &src);
931 	if (!parent)
932 		return 0;
933 
934 	bh_lock_sock(parent);
935 
936 	/* Check for backlog size */
937 	if (sk_acceptq_is_full(parent)) {
938 		BT_DBG("backlog full %d", parent->sk_ack_backlog);
939 		goto done;
940 	}
941 
942 	sk = rfcomm_sock_alloc(sock_net(parent), NULL, BTPROTO_RFCOMM, GFP_ATOMIC);
943 	if (!sk)
944 		goto done;
945 
946 	bt_sock_reclassify_lock(sk, BTPROTO_RFCOMM);
947 
948 	rfcomm_sock_init(sk, parent);
949 	bacpy(&bt_sk(sk)->src, &src);
950 	bacpy(&bt_sk(sk)->dst, &dst);
951 	rfcomm_pi(sk)->channel = channel;
952 
953 	sk->sk_state = BT_CONFIG;
954 	bt_accept_enqueue(parent, sk);
955 
956 	/* Accept connection and return socket DLC */
957 	*d = rfcomm_pi(sk)->dlc;
958 	result = 1;
959 
960 done:
961 	bh_unlock_sock(parent);
962 
963 	if (test_bit(BT_SK_DEFER_SETUP, &bt_sk(parent)->flags))
964 		parent->sk_state_change(parent);
965 
966 	return result;
967 }
968 
969 static int rfcomm_sock_debugfs_show(struct seq_file *f, void *p)
970 {
971 	struct sock *sk;
972 
973 	read_lock(&rfcomm_sk_list.lock);
974 
975 	sk_for_each(sk, &rfcomm_sk_list.head) {
976 		seq_printf(f, "%pMR %pMR %d %d\n",
977 			   &bt_sk(sk)->src, &bt_sk(sk)->dst,
978 			   sk->sk_state, rfcomm_pi(sk)->channel);
979 	}
980 
981 	read_unlock(&rfcomm_sk_list.lock);
982 
983 	return 0;
984 }
985 
986 static int rfcomm_sock_debugfs_open(struct inode *inode, struct file *file)
987 {
988 	return single_open(file, rfcomm_sock_debugfs_show, inode->i_private);
989 }
990 
991 static const struct file_operations rfcomm_sock_debugfs_fops = {
992 	.open		= rfcomm_sock_debugfs_open,
993 	.read		= seq_read,
994 	.llseek		= seq_lseek,
995 	.release	= single_release,
996 };
997 
998 static struct dentry *rfcomm_sock_debugfs;
999 
1000 static const struct proto_ops rfcomm_sock_ops = {
1001 	.family		= PF_BLUETOOTH,
1002 	.owner		= THIS_MODULE,
1003 	.release	= rfcomm_sock_release,
1004 	.bind		= rfcomm_sock_bind,
1005 	.connect	= rfcomm_sock_connect,
1006 	.listen		= rfcomm_sock_listen,
1007 	.accept		= rfcomm_sock_accept,
1008 	.getname	= rfcomm_sock_getname,
1009 	.sendmsg	= rfcomm_sock_sendmsg,
1010 	.recvmsg	= rfcomm_sock_recvmsg,
1011 	.shutdown	= rfcomm_sock_shutdown,
1012 	.setsockopt	= rfcomm_sock_setsockopt,
1013 	.getsockopt	= rfcomm_sock_getsockopt,
1014 	.ioctl		= rfcomm_sock_ioctl,
1015 	.poll		= bt_sock_poll,
1016 	.socketpair	= sock_no_socketpair,
1017 	.mmap		= sock_no_mmap
1018 };
1019 
1020 static const struct net_proto_family rfcomm_sock_family_ops = {
1021 	.family		= PF_BLUETOOTH,
1022 	.owner		= THIS_MODULE,
1023 	.create		= rfcomm_sock_create
1024 };
1025 
1026 int __init rfcomm_init_sockets(void)
1027 {
1028 	int err;
1029 
1030 	err = proto_register(&rfcomm_proto, 0);
1031 	if (err < 0)
1032 		return err;
1033 
1034 	err = bt_sock_register(BTPROTO_RFCOMM, &rfcomm_sock_family_ops);
1035 	if (err < 0) {
1036 		BT_ERR("RFCOMM socket layer registration failed");
1037 		goto error;
1038 	}
1039 
1040 	err = bt_procfs_init(&init_net, "rfcomm", &rfcomm_sk_list, NULL);
1041 	if (err < 0) {
1042 		BT_ERR("Failed to create RFCOMM proc file");
1043 		bt_sock_unregister(BTPROTO_RFCOMM);
1044 		goto error;
1045 	}
1046 
1047 	if (bt_debugfs) {
1048 		rfcomm_sock_debugfs = debugfs_create_file("rfcomm", 0444,
1049 				bt_debugfs, NULL, &rfcomm_sock_debugfs_fops);
1050 		if (!rfcomm_sock_debugfs)
1051 			BT_ERR("Failed to create RFCOMM debug file");
1052 	}
1053 
1054 	BT_INFO("RFCOMM socket layer initialized");
1055 
1056 	return 0;
1057 
1058 error:
1059 	proto_unregister(&rfcomm_proto);
1060 	return err;
1061 }
1062 
1063 void __exit rfcomm_cleanup_sockets(void)
1064 {
1065 	bt_procfs_cleanup(&init_net, "rfcomm");
1066 
1067 	debugfs_remove(rfcomm_sock_debugfs);
1068 
1069 	bt_sock_unregister(BTPROTO_RFCOMM);
1070 
1071 	proto_unregister(&rfcomm_proto);
1072 }
1073