xref: /openbmc/linux/net/bluetooth/rfcomm/sock.c (revision 9f380456)
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/module.h>
29 
30 #include <linux/types.h>
31 #include <linux/errno.h>
32 #include <linux/kernel.h>
33 #include <linux/sched.h>
34 #include <linux/slab.h>
35 #include <linux/poll.h>
36 #include <linux/fcntl.h>
37 #include <linux/init.h>
38 #include <linux/interrupt.h>
39 #include <linux/socket.h>
40 #include <linux/skbuff.h>
41 #include <linux/list.h>
42 #include <linux/device.h>
43 #include <linux/debugfs.h>
44 #include <linux/seq_file.h>
45 #include <linux/security.h>
46 #include <net/sock.h>
47 
48 #include <linux/uaccess.h>
49 
50 #include <net/bluetooth/bluetooth.h>
51 #include <net/bluetooth/hci_core.h>
52 #include <net/bluetooth/l2cap.h>
53 #include <net/bluetooth/rfcomm.h>
54 
55 static const struct proto_ops rfcomm_sock_ops;
56 
57 static struct bt_sock_list rfcomm_sk_list = {
58 	.lock = __RW_LOCK_UNLOCKED(rfcomm_sk_list.lock)
59 };
60 
61 static void rfcomm_sock_close(struct sock *sk);
62 static void rfcomm_sock_kill(struct sock *sk);
63 
64 /* ---- DLC callbacks ----
65  *
66  * called under rfcomm_dlc_lock()
67  */
68 static void rfcomm_sk_data_ready(struct rfcomm_dlc *d, struct sk_buff *skb)
69 {
70 	struct sock *sk = d->owner;
71 	if (!sk)
72 		return;
73 
74 	atomic_add(skb->len, &sk->sk_rmem_alloc);
75 	skb_queue_tail(&sk->sk_receive_queue, skb);
76 	sk->sk_data_ready(sk, skb->len);
77 
78 	if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf)
79 		rfcomm_dlc_throttle(d);
80 }
81 
82 static void rfcomm_sk_state_change(struct rfcomm_dlc *d, int err)
83 {
84 	struct sock *sk = d->owner, *parent;
85 	unsigned long flags;
86 
87 	if (!sk)
88 		return;
89 
90 	BT_DBG("dlc %p state %ld err %d", d, d->state, err);
91 
92 	local_irq_save(flags);
93 	bh_lock_sock(sk);
94 
95 	if (err)
96 		sk->sk_err = err;
97 
98 	sk->sk_state = d->state;
99 
100 	parent = bt_sk(sk)->parent;
101 	if (parent) {
102 		if (d->state == BT_CLOSED) {
103 			sock_set_flag(sk, SOCK_ZAPPED);
104 			bt_accept_unlink(sk);
105 		}
106 		parent->sk_data_ready(parent, 0);
107 	} else {
108 		if (d->state == BT_CONNECTED)
109 			rfcomm_session_getaddr(d->session, &bt_sk(sk)->src, NULL);
110 		sk->sk_state_change(sk);
111 	}
112 
113 	bh_unlock_sock(sk);
114 	local_irq_restore(flags);
115 
116 	if (parent && sock_flag(sk, SOCK_ZAPPED)) {
117 		/* We have to drop DLC lock here, otherwise
118 		 * rfcomm_sock_destruct() will dead lock. */
119 		rfcomm_dlc_unlock(d);
120 		rfcomm_sock_kill(sk);
121 		rfcomm_dlc_lock(d);
122 	}
123 }
124 
125 /* ---- Socket functions ---- */
126 static struct sock *__rfcomm_get_sock_by_addr(u8 channel, bdaddr_t *src)
127 {
128 	struct sock *sk = NULL;
129 	struct hlist_node *node;
130 
131 	sk_for_each(sk, node, &rfcomm_sk_list.head) {
132 		if (rfcomm_pi(sk)->channel == channel &&
133 				!bacmp(&bt_sk(sk)->src, src))
134 			break;
135 	}
136 
137 	return node ? sk : NULL;
138 }
139 
140 /* Find socket with channel and source bdaddr.
141  * Returns closest match.
142  */
143 static struct sock *rfcomm_get_sock_by_channel(int state, u8 channel, bdaddr_t *src)
144 {
145 	struct sock *sk = NULL, *sk1 = NULL;
146 	struct hlist_node *node;
147 
148 	read_lock(&rfcomm_sk_list.lock);
149 
150 	sk_for_each(sk, node, &rfcomm_sk_list.head) {
151 		if (state && sk->sk_state != state)
152 			continue;
153 
154 		if (rfcomm_pi(sk)->channel == channel) {
155 			/* Exact match. */
156 			if (!bacmp(&bt_sk(sk)->src, src))
157 				break;
158 
159 			/* Closest match */
160 			if (!bacmp(&bt_sk(sk)->src, BDADDR_ANY))
161 				sk1 = sk;
162 		}
163 	}
164 
165 	read_unlock(&rfcomm_sk_list.lock);
166 
167 	return node ? sk : sk1;
168 }
169 
170 static void rfcomm_sock_destruct(struct sock *sk)
171 {
172 	struct rfcomm_dlc *d = rfcomm_pi(sk)->dlc;
173 
174 	BT_DBG("sk %p dlc %p", sk, d);
175 
176 	skb_queue_purge(&sk->sk_receive_queue);
177 	skb_queue_purge(&sk->sk_write_queue);
178 
179 	rfcomm_dlc_lock(d);
180 	rfcomm_pi(sk)->dlc = NULL;
181 
182 	/* Detach DLC if it's owned by this socket */
183 	if (d->owner == sk)
184 		d->owner = NULL;
185 	rfcomm_dlc_unlock(d);
186 
187 	rfcomm_dlc_put(d);
188 }
189 
190 static void rfcomm_sock_cleanup_listen(struct sock *parent)
191 {
192 	struct sock *sk;
193 
194 	BT_DBG("parent %p", parent);
195 
196 	/* Close not yet accepted dlcs */
197 	while ((sk = bt_accept_dequeue(parent, NULL))) {
198 		rfcomm_sock_close(sk);
199 		rfcomm_sock_kill(sk);
200 	}
201 
202 	parent->sk_state  = BT_CLOSED;
203 	sock_set_flag(parent, SOCK_ZAPPED);
204 }
205 
206 /* Kill socket (only if zapped and orphan)
207  * Must be called on unlocked socket.
208  */
209 static void rfcomm_sock_kill(struct sock *sk)
210 {
211 	if (!sock_flag(sk, SOCK_ZAPPED) || sk->sk_socket)
212 		return;
213 
214 	BT_DBG("sk %p state %d refcnt %d", sk, sk->sk_state, atomic_read(&sk->sk_refcnt));
215 
216 	/* Kill poor orphan */
217 	bt_sock_unlink(&rfcomm_sk_list, sk);
218 	sock_set_flag(sk, SOCK_DEAD);
219 	sock_put(sk);
220 }
221 
222 static void __rfcomm_sock_close(struct sock *sk)
223 {
224 	struct rfcomm_dlc *d = rfcomm_pi(sk)->dlc;
225 
226 	BT_DBG("sk %p state %d socket %p", sk, sk->sk_state, sk->sk_socket);
227 
228 	switch (sk->sk_state) {
229 	case BT_LISTEN:
230 		rfcomm_sock_cleanup_listen(sk);
231 		break;
232 
233 	case BT_CONNECT:
234 	case BT_CONNECT2:
235 	case BT_CONFIG:
236 	case BT_CONNECTED:
237 		rfcomm_dlc_close(d, 0);
238 
239 	default:
240 		sock_set_flag(sk, SOCK_ZAPPED);
241 		break;
242 	}
243 }
244 
245 /* Close socket.
246  * Must be called on unlocked socket.
247  */
248 static void rfcomm_sock_close(struct sock *sk)
249 {
250 	lock_sock(sk);
251 	__rfcomm_sock_close(sk);
252 	release_sock(sk);
253 }
254 
255 static void rfcomm_sock_init(struct sock *sk, struct sock *parent)
256 {
257 	struct rfcomm_pinfo *pi = rfcomm_pi(sk);
258 
259 	BT_DBG("sk %p", sk);
260 
261 	if (parent) {
262 		sk->sk_type = parent->sk_type;
263 		pi->dlc->defer_setup = bt_sk(parent)->defer_setup;
264 
265 		pi->sec_level = rfcomm_pi(parent)->sec_level;
266 		pi->role_switch = rfcomm_pi(parent)->role_switch;
267 
268 		security_sk_clone(parent, sk);
269 	} else {
270 		pi->dlc->defer_setup = 0;
271 
272 		pi->sec_level = BT_SECURITY_LOW;
273 		pi->role_switch = 0;
274 	}
275 
276 	pi->dlc->sec_level = pi->sec_level;
277 	pi->dlc->role_switch = pi->role_switch;
278 }
279 
280 static struct proto rfcomm_proto = {
281 	.name		= "RFCOMM",
282 	.owner		= THIS_MODULE,
283 	.obj_size	= sizeof(struct rfcomm_pinfo)
284 };
285 
286 static struct sock *rfcomm_sock_alloc(struct net *net, struct socket *sock, int proto, gfp_t prio)
287 {
288 	struct rfcomm_dlc *d;
289 	struct sock *sk;
290 
291 	sk = sk_alloc(net, PF_BLUETOOTH, prio, &rfcomm_proto);
292 	if (!sk)
293 		return NULL;
294 
295 	sock_init_data(sock, sk);
296 	INIT_LIST_HEAD(&bt_sk(sk)->accept_q);
297 
298 	d = rfcomm_dlc_alloc(prio);
299 	if (!d) {
300 		sk_free(sk);
301 		return NULL;
302 	}
303 
304 	d->data_ready   = rfcomm_sk_data_ready;
305 	d->state_change = rfcomm_sk_state_change;
306 
307 	rfcomm_pi(sk)->dlc = d;
308 	d->owner = sk;
309 
310 	sk->sk_destruct = rfcomm_sock_destruct;
311 	sk->sk_sndtimeo = RFCOMM_CONN_TIMEOUT;
312 
313 	sk->sk_sndbuf = RFCOMM_MAX_CREDITS * RFCOMM_DEFAULT_MTU * 10;
314 	sk->sk_rcvbuf = RFCOMM_MAX_CREDITS * RFCOMM_DEFAULT_MTU * 10;
315 
316 	sock_reset_flag(sk, SOCK_ZAPPED);
317 
318 	sk->sk_protocol = proto;
319 	sk->sk_state    = BT_OPEN;
320 
321 	bt_sock_link(&rfcomm_sk_list, sk);
322 
323 	BT_DBG("sk %p", sk);
324 	return sk;
325 }
326 
327 static int rfcomm_sock_create(struct net *net, struct socket *sock,
328 			      int protocol, int kern)
329 {
330 	struct sock *sk;
331 
332 	BT_DBG("sock %p", sock);
333 
334 	sock->state = SS_UNCONNECTED;
335 
336 	if (sock->type != SOCK_STREAM && sock->type != SOCK_RAW)
337 		return -ESOCKTNOSUPPORT;
338 
339 	sock->ops = &rfcomm_sock_ops;
340 
341 	sk = rfcomm_sock_alloc(net, sock, protocol, GFP_ATOMIC);
342 	if (!sk)
343 		return -ENOMEM;
344 
345 	rfcomm_sock_init(sk, NULL);
346 	return 0;
347 }
348 
349 static int rfcomm_sock_bind(struct socket *sock, struct sockaddr *addr, int addr_len)
350 {
351 	struct sockaddr_rc *sa = (struct sockaddr_rc *) addr;
352 	struct sock *sk = sock->sk;
353 	int err = 0;
354 
355 	BT_DBG("sk %p %s", sk, batostr(&sa->rc_bdaddr));
356 
357 	if (!addr || addr->sa_family != AF_BLUETOOTH)
358 		return -EINVAL;
359 
360 	lock_sock(sk);
361 
362 	if (sk->sk_state != BT_OPEN) {
363 		err = -EBADFD;
364 		goto done;
365 	}
366 
367 	if (sk->sk_type != SOCK_STREAM) {
368 		err = -EINVAL;
369 		goto done;
370 	}
371 
372 	write_lock(&rfcomm_sk_list.lock);
373 
374 	if (sa->rc_channel && __rfcomm_get_sock_by_addr(sa->rc_channel, &sa->rc_bdaddr)) {
375 		err = -EADDRINUSE;
376 	} else {
377 		/* Save source address */
378 		bacpy(&bt_sk(sk)->src, &sa->rc_bdaddr);
379 		rfcomm_pi(sk)->channel = sa->rc_channel;
380 		sk->sk_state = BT_BOUND;
381 	}
382 
383 	write_unlock(&rfcomm_sk_list.lock);
384 
385 done:
386 	release_sock(sk);
387 	return err;
388 }
389 
390 static int rfcomm_sock_connect(struct socket *sock, struct sockaddr *addr, int alen, int flags)
391 {
392 	struct sockaddr_rc *sa = (struct sockaddr_rc *) addr;
393 	struct sock *sk = sock->sk;
394 	struct rfcomm_dlc *d = rfcomm_pi(sk)->dlc;
395 	int err = 0;
396 
397 	BT_DBG("sk %p", sk);
398 
399 	if (alen < sizeof(struct sockaddr_rc) ||
400 	    addr->sa_family != AF_BLUETOOTH)
401 		return -EINVAL;
402 
403 	lock_sock(sk);
404 
405 	if (sk->sk_state != BT_OPEN && sk->sk_state != BT_BOUND) {
406 		err = -EBADFD;
407 		goto done;
408 	}
409 
410 	if (sk->sk_type != SOCK_STREAM) {
411 		err = -EINVAL;
412 		goto done;
413 	}
414 
415 	sk->sk_state = BT_CONNECT;
416 	bacpy(&bt_sk(sk)->dst, &sa->rc_bdaddr);
417 	rfcomm_pi(sk)->channel = sa->rc_channel;
418 
419 	d->sec_level = rfcomm_pi(sk)->sec_level;
420 	d->role_switch = rfcomm_pi(sk)->role_switch;
421 
422 	err = rfcomm_dlc_open(d, &bt_sk(sk)->src, &sa->rc_bdaddr, sa->rc_channel);
423 	if (!err)
424 		err = bt_sock_wait_state(sk, BT_CONNECTED,
425 				sock_sndtimeo(sk, flags & O_NONBLOCK));
426 
427 done:
428 	release_sock(sk);
429 	return err;
430 }
431 
432 static int rfcomm_sock_listen(struct socket *sock, int backlog)
433 {
434 	struct sock *sk = sock->sk;
435 	int err = 0;
436 
437 	BT_DBG("sk %p backlog %d", sk, backlog);
438 
439 	lock_sock(sk);
440 
441 	if (sk->sk_state != BT_BOUND) {
442 		err = -EBADFD;
443 		goto done;
444 	}
445 
446 	if (sk->sk_type != SOCK_STREAM) {
447 		err = -EINVAL;
448 		goto done;
449 	}
450 
451 	if (!rfcomm_pi(sk)->channel) {
452 		bdaddr_t *src = &bt_sk(sk)->src;
453 		u8 channel;
454 
455 		err = -EINVAL;
456 
457 		write_lock(&rfcomm_sk_list.lock);
458 
459 		for (channel = 1; channel < 31; channel++)
460 			if (!__rfcomm_get_sock_by_addr(channel, src)) {
461 				rfcomm_pi(sk)->channel = channel;
462 				err = 0;
463 				break;
464 			}
465 
466 		write_unlock(&rfcomm_sk_list.lock);
467 
468 		if (err < 0)
469 			goto done;
470 	}
471 
472 	sk->sk_max_ack_backlog = backlog;
473 	sk->sk_ack_backlog = 0;
474 	sk->sk_state = BT_LISTEN;
475 
476 done:
477 	release_sock(sk);
478 	return err;
479 }
480 
481 static int rfcomm_sock_accept(struct socket *sock, struct socket *newsock, int flags)
482 {
483 	DECLARE_WAITQUEUE(wait, current);
484 	struct sock *sk = sock->sk, *nsk;
485 	long timeo;
486 	int err = 0;
487 
488 	lock_sock(sk);
489 
490 	if (sk->sk_type != SOCK_STREAM) {
491 		err = -EINVAL;
492 		goto done;
493 	}
494 
495 	timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
496 
497 	BT_DBG("sk %p timeo %ld", sk, timeo);
498 
499 	/* Wait for an incoming connection. (wake-one). */
500 	add_wait_queue_exclusive(sk_sleep(sk), &wait);
501 	while (1) {
502 		set_current_state(TASK_INTERRUPTIBLE);
503 
504 		if (sk->sk_state != BT_LISTEN) {
505 			err = -EBADFD;
506 			break;
507 		}
508 
509 		nsk = bt_accept_dequeue(sk, newsock);
510 		if (nsk)
511 			break;
512 
513 		if (!timeo) {
514 			err = -EAGAIN;
515 			break;
516 		}
517 
518 		if (signal_pending(current)) {
519 			err = sock_intr_errno(timeo);
520 			break;
521 		}
522 
523 		release_sock(sk);
524 		timeo = schedule_timeout(timeo);
525 		lock_sock(sk);
526 	}
527 	__set_current_state(TASK_RUNNING);
528 	remove_wait_queue(sk_sleep(sk), &wait);
529 
530 	if (err)
531 		goto done;
532 
533 	newsock->state = SS_CONNECTED;
534 
535 	BT_DBG("new socket %p", nsk);
536 
537 done:
538 	release_sock(sk);
539 	return err;
540 }
541 
542 static int rfcomm_sock_getname(struct socket *sock, struct sockaddr *addr, int *len, int peer)
543 {
544 	struct sockaddr_rc *sa = (struct sockaddr_rc *) addr;
545 	struct sock *sk = sock->sk;
546 
547 	BT_DBG("sock %p, sk %p", sock, sk);
548 
549 	sa->rc_family  = AF_BLUETOOTH;
550 	sa->rc_channel = rfcomm_pi(sk)->channel;
551 	if (peer)
552 		bacpy(&sa->rc_bdaddr, &bt_sk(sk)->dst);
553 	else
554 		bacpy(&sa->rc_bdaddr, &bt_sk(sk)->src);
555 
556 	*len = sizeof(struct sockaddr_rc);
557 	return 0;
558 }
559 
560 static int rfcomm_sock_sendmsg(struct kiocb *iocb, struct socket *sock,
561 			       struct msghdr *msg, size_t len)
562 {
563 	struct sock *sk = sock->sk;
564 	struct rfcomm_dlc *d = rfcomm_pi(sk)->dlc;
565 	struct sk_buff *skb;
566 	int sent = 0;
567 
568 	if (test_bit(RFCOMM_DEFER_SETUP, &d->flags))
569 		return -ENOTCONN;
570 
571 	if (msg->msg_flags & MSG_OOB)
572 		return -EOPNOTSUPP;
573 
574 	if (sk->sk_shutdown & SEND_SHUTDOWN)
575 		return -EPIPE;
576 
577 	BT_DBG("sock %p, sk %p", sock, sk);
578 
579 	lock_sock(sk);
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_fromiovec(skb_put(skb, size), msg->msg_iov, 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 	release_sock(sk);
617 
618 	return sent;
619 }
620 
621 static int rfcomm_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
622 			       struct msghdr *msg, size_t size, int flags)
623 {
624 	struct sock *sk = sock->sk;
625 	struct rfcomm_dlc *d = rfcomm_pi(sk)->dlc;
626 	int len;
627 
628 	if (test_and_clear_bit(RFCOMM_DEFER_SETUP, &d->flags)) {
629 		rfcomm_dlc_accept(d);
630 		return 0;
631 	}
632 
633 	len = bt_sock_stream_recvmsg(iocb, sock, msg, size, flags);
634 
635 	lock_sock(sk);
636 	if (!(flags & MSG_PEEK) && len > 0)
637 		atomic_sub(len, &sk->sk_rmem_alloc);
638 
639 	if (atomic_read(&sk->sk_rmem_alloc) <= (sk->sk_rcvbuf >> 2))
640 		rfcomm_dlc_unthrottle(rfcomm_pi(sk)->dlc);
641 	release_sock(sk);
642 
643 	return len;
644 }
645 
646 static int rfcomm_sock_setsockopt_old(struct socket *sock, int optname, char __user *optval, unsigned int optlen)
647 {
648 	struct sock *sk = sock->sk;
649 	int err = 0;
650 	u32 opt;
651 
652 	BT_DBG("sk %p", sk);
653 
654 	lock_sock(sk);
655 
656 	switch (optname) {
657 	case RFCOMM_LM:
658 		if (get_user(opt, (u32 __user *) optval)) {
659 			err = -EFAULT;
660 			break;
661 		}
662 
663 		if (opt & RFCOMM_LM_AUTH)
664 			rfcomm_pi(sk)->sec_level = BT_SECURITY_LOW;
665 		if (opt & RFCOMM_LM_ENCRYPT)
666 			rfcomm_pi(sk)->sec_level = BT_SECURITY_MEDIUM;
667 		if (opt & RFCOMM_LM_SECURE)
668 			rfcomm_pi(sk)->sec_level = BT_SECURITY_HIGH;
669 
670 		rfcomm_pi(sk)->role_switch = (opt & RFCOMM_LM_MASTER);
671 		break;
672 
673 	default:
674 		err = -ENOPROTOOPT;
675 		break;
676 	}
677 
678 	release_sock(sk);
679 	return err;
680 }
681 
682 static int rfcomm_sock_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen)
683 {
684 	struct sock *sk = sock->sk;
685 	struct bt_security sec;
686 	int err = 0;
687 	size_t len;
688 	u32 opt;
689 
690 	BT_DBG("sk %p", sk);
691 
692 	if (level == SOL_RFCOMM)
693 		return rfcomm_sock_setsockopt_old(sock, optname, optval, optlen);
694 
695 	if (level != SOL_BLUETOOTH)
696 		return -ENOPROTOOPT;
697 
698 	lock_sock(sk);
699 
700 	switch (optname) {
701 	case BT_SECURITY:
702 		if (sk->sk_type != SOCK_STREAM) {
703 			err = -EINVAL;
704 			break;
705 		}
706 
707 		sec.level = BT_SECURITY_LOW;
708 
709 		len = min_t(unsigned int, sizeof(sec), optlen);
710 		if (copy_from_user((char *) &sec, optval, len)) {
711 			err = -EFAULT;
712 			break;
713 		}
714 
715 		if (sec.level > BT_SECURITY_HIGH) {
716 			err = -EINVAL;
717 			break;
718 		}
719 
720 		rfcomm_pi(sk)->sec_level = sec.level;
721 		break;
722 
723 	case BT_DEFER_SETUP:
724 		if (sk->sk_state != BT_BOUND && sk->sk_state != BT_LISTEN) {
725 			err = -EINVAL;
726 			break;
727 		}
728 
729 		if (get_user(opt, (u32 __user *) optval)) {
730 			err = -EFAULT;
731 			break;
732 		}
733 
734 		bt_sk(sk)->defer_setup = opt;
735 		break;
736 
737 	default:
738 		err = -ENOPROTOOPT;
739 		break;
740 	}
741 
742 	release_sock(sk);
743 	return err;
744 }
745 
746 static int rfcomm_sock_getsockopt_old(struct socket *sock, int optname, char __user *optval, int __user *optlen)
747 {
748 	struct sock *sk = sock->sk;
749 	struct rfcomm_conninfo cinfo;
750 	struct l2cap_conn *conn = l2cap_pi(sk)->chan->conn;
751 	int len, err = 0;
752 	u32 opt;
753 
754 	BT_DBG("sk %p", sk);
755 
756 	if (get_user(len, optlen))
757 		return -EFAULT;
758 
759 	lock_sock(sk);
760 
761 	switch (optname) {
762 	case RFCOMM_LM:
763 		switch (rfcomm_pi(sk)->sec_level) {
764 		case BT_SECURITY_LOW:
765 			opt = RFCOMM_LM_AUTH;
766 			break;
767 		case BT_SECURITY_MEDIUM:
768 			opt = RFCOMM_LM_AUTH | RFCOMM_LM_ENCRYPT;
769 			break;
770 		case BT_SECURITY_HIGH:
771 			opt = RFCOMM_LM_AUTH | RFCOMM_LM_ENCRYPT |
772 							RFCOMM_LM_SECURE;
773 			break;
774 		default:
775 			opt = 0;
776 			break;
777 		}
778 
779 		if (rfcomm_pi(sk)->role_switch)
780 			opt |= RFCOMM_LM_MASTER;
781 
782 		if (put_user(opt, (u32 __user *) optval))
783 			err = -EFAULT;
784 		break;
785 
786 	case RFCOMM_CONNINFO:
787 		if (sk->sk_state != BT_CONNECTED &&
788 					!rfcomm_pi(sk)->dlc->defer_setup) {
789 			err = -ENOTCONN;
790 			break;
791 		}
792 
793 		memset(&cinfo, 0, sizeof(cinfo));
794 		cinfo.hci_handle = conn->hcon->handle;
795 		memcpy(cinfo.dev_class, conn->hcon->dev_class, 3);
796 
797 		len = min_t(unsigned int, len, sizeof(cinfo));
798 		if (copy_to_user(optval, (char *) &cinfo, len))
799 			err = -EFAULT;
800 
801 		break;
802 
803 	default:
804 		err = -ENOPROTOOPT;
805 		break;
806 	}
807 
808 	release_sock(sk);
809 	return err;
810 }
811 
812 static int rfcomm_sock_getsockopt(struct socket *sock, int level, int optname, char __user *optval, int __user *optlen)
813 {
814 	struct sock *sk = sock->sk;
815 	struct bt_security sec;
816 	int len, err = 0;
817 
818 	BT_DBG("sk %p", sk);
819 
820 	if (level == SOL_RFCOMM)
821 		return rfcomm_sock_getsockopt_old(sock, optname, optval, optlen);
822 
823 	if (level != SOL_BLUETOOTH)
824 		return -ENOPROTOOPT;
825 
826 	if (get_user(len, optlen))
827 		return -EFAULT;
828 
829 	lock_sock(sk);
830 
831 	switch (optname) {
832 	case BT_SECURITY:
833 		if (sk->sk_type != SOCK_STREAM) {
834 			err = -EINVAL;
835 			break;
836 		}
837 
838 		sec.level = rfcomm_pi(sk)->sec_level;
839 
840 		len = min_t(unsigned int, len, sizeof(sec));
841 		if (copy_to_user(optval, (char *) &sec, len))
842 			err = -EFAULT;
843 
844 		break;
845 
846 	case BT_DEFER_SETUP:
847 		if (sk->sk_state != BT_BOUND && sk->sk_state != BT_LISTEN) {
848 			err = -EINVAL;
849 			break;
850 		}
851 
852 		if (put_user(bt_sk(sk)->defer_setup, (u32 __user *) optval))
853 			err = -EFAULT;
854 
855 		break;
856 
857 	default:
858 		err = -ENOPROTOOPT;
859 		break;
860 	}
861 
862 	release_sock(sk);
863 	return err;
864 }
865 
866 static int rfcomm_sock_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
867 {
868 	struct sock *sk __maybe_unused = sock->sk;
869 	int err;
870 
871 	BT_DBG("sk %p cmd %x arg %lx", sk, cmd, arg);
872 
873 	err = bt_sock_ioctl(sock, cmd, arg);
874 
875 	if (err == -ENOIOCTLCMD) {
876 #ifdef CONFIG_BT_RFCOMM_TTY
877 		lock_sock(sk);
878 		err = rfcomm_dev_ioctl(sk, cmd, (void __user *) arg);
879 		release_sock(sk);
880 #else
881 		err = -EOPNOTSUPP;
882 #endif
883 	}
884 
885 	return err;
886 }
887 
888 static int rfcomm_sock_shutdown(struct socket *sock, int how)
889 {
890 	struct sock *sk = sock->sk;
891 	int err = 0;
892 
893 	BT_DBG("sock %p, sk %p", sock, sk);
894 
895 	if (!sk)
896 		return 0;
897 
898 	lock_sock(sk);
899 	if (!sk->sk_shutdown) {
900 		sk->sk_shutdown = SHUTDOWN_MASK;
901 		__rfcomm_sock_close(sk);
902 
903 		if (sock_flag(sk, SOCK_LINGER) && sk->sk_lingertime)
904 			err = bt_sock_wait_state(sk, BT_CLOSED, sk->sk_lingertime);
905 	}
906 	release_sock(sk);
907 	return err;
908 }
909 
910 static int rfcomm_sock_release(struct socket *sock)
911 {
912 	struct sock *sk = sock->sk;
913 	int err;
914 
915 	BT_DBG("sock %p, sk %p", sock, sk);
916 
917 	if (!sk)
918 		return 0;
919 
920 	err = rfcomm_sock_shutdown(sock, 2);
921 
922 	sock_orphan(sk);
923 	rfcomm_sock_kill(sk);
924 	return err;
925 }
926 
927 /* ---- RFCOMM core layer callbacks ----
928  *
929  * called under rfcomm_lock()
930  */
931 int rfcomm_connect_ind(struct rfcomm_session *s, u8 channel, struct rfcomm_dlc **d)
932 {
933 	struct sock *sk, *parent;
934 	bdaddr_t src, dst;
935 	int result = 0;
936 
937 	BT_DBG("session %p channel %d", s, channel);
938 
939 	rfcomm_session_getaddr(s, &src, &dst);
940 
941 	/* Check if we have socket listening on channel */
942 	parent = rfcomm_get_sock_by_channel(BT_LISTEN, channel, &src);
943 	if (!parent)
944 		return 0;
945 
946 	bh_lock_sock(parent);
947 
948 	/* Check for backlog size */
949 	if (sk_acceptq_is_full(parent)) {
950 		BT_DBG("backlog full %d", parent->sk_ack_backlog);
951 		goto done;
952 	}
953 
954 	sk = rfcomm_sock_alloc(sock_net(parent), NULL, BTPROTO_RFCOMM, GFP_ATOMIC);
955 	if (!sk)
956 		goto done;
957 
958 	bt_sock_reclassify_lock(sk, BTPROTO_RFCOMM);
959 
960 	rfcomm_sock_init(sk, parent);
961 	bacpy(&bt_sk(sk)->src, &src);
962 	bacpy(&bt_sk(sk)->dst, &dst);
963 	rfcomm_pi(sk)->channel = channel;
964 
965 	sk->sk_state = BT_CONFIG;
966 	bt_accept_enqueue(parent, sk);
967 
968 	/* Accept connection and return socket DLC */
969 	*d = rfcomm_pi(sk)->dlc;
970 	result = 1;
971 
972 done:
973 	bh_unlock_sock(parent);
974 
975 	if (bt_sk(parent)->defer_setup)
976 		parent->sk_state_change(parent);
977 
978 	return result;
979 }
980 
981 static int rfcomm_sock_debugfs_show(struct seq_file *f, void *p)
982 {
983 	struct sock *sk;
984 	struct hlist_node *node;
985 
986 	read_lock(&rfcomm_sk_list.lock);
987 
988 	sk_for_each(sk, node, &rfcomm_sk_list.head) {
989 		seq_printf(f, "%s %s %d %d\n",
990 				batostr(&bt_sk(sk)->src),
991 				batostr(&bt_sk(sk)->dst),
992 				sk->sk_state, rfcomm_pi(sk)->channel);
993 	}
994 
995 	read_unlock(&rfcomm_sk_list.lock);
996 
997 	return 0;
998 }
999 
1000 static int rfcomm_sock_debugfs_open(struct inode *inode, struct file *file)
1001 {
1002 	return single_open(file, rfcomm_sock_debugfs_show, inode->i_private);
1003 }
1004 
1005 static const struct file_operations rfcomm_sock_debugfs_fops = {
1006 	.open		= rfcomm_sock_debugfs_open,
1007 	.read		= seq_read,
1008 	.llseek		= seq_lseek,
1009 	.release	= single_release,
1010 };
1011 
1012 static struct dentry *rfcomm_sock_debugfs;
1013 
1014 static const struct proto_ops rfcomm_sock_ops = {
1015 	.family		= PF_BLUETOOTH,
1016 	.owner		= THIS_MODULE,
1017 	.release	= rfcomm_sock_release,
1018 	.bind		= rfcomm_sock_bind,
1019 	.connect	= rfcomm_sock_connect,
1020 	.listen		= rfcomm_sock_listen,
1021 	.accept		= rfcomm_sock_accept,
1022 	.getname	= rfcomm_sock_getname,
1023 	.sendmsg	= rfcomm_sock_sendmsg,
1024 	.recvmsg	= rfcomm_sock_recvmsg,
1025 	.shutdown	= rfcomm_sock_shutdown,
1026 	.setsockopt	= rfcomm_sock_setsockopt,
1027 	.getsockopt	= rfcomm_sock_getsockopt,
1028 	.ioctl		= rfcomm_sock_ioctl,
1029 	.poll		= bt_sock_poll,
1030 	.socketpair	= sock_no_socketpair,
1031 	.mmap		= sock_no_mmap
1032 };
1033 
1034 static const struct net_proto_family rfcomm_sock_family_ops = {
1035 	.family		= PF_BLUETOOTH,
1036 	.owner		= THIS_MODULE,
1037 	.create		= rfcomm_sock_create
1038 };
1039 
1040 int __init rfcomm_init_sockets(void)
1041 {
1042 	int err;
1043 
1044 	err = proto_register(&rfcomm_proto, 0);
1045 	if (err < 0)
1046 		return err;
1047 
1048 	err = bt_sock_register(BTPROTO_RFCOMM, &rfcomm_sock_family_ops);
1049 	if (err < 0)
1050 		goto error;
1051 
1052 	if (bt_debugfs) {
1053 		rfcomm_sock_debugfs = debugfs_create_file("rfcomm", 0444,
1054 				bt_debugfs, NULL, &rfcomm_sock_debugfs_fops);
1055 		if (!rfcomm_sock_debugfs)
1056 			BT_ERR("Failed to create RFCOMM debug file");
1057 	}
1058 
1059 	BT_INFO("RFCOMM socket layer initialized");
1060 
1061 	return 0;
1062 
1063 error:
1064 	BT_ERR("RFCOMM socket layer registration failed");
1065 	proto_unregister(&rfcomm_proto);
1066 	return err;
1067 }
1068 
1069 void __exit rfcomm_cleanup_sockets(void)
1070 {
1071 	debugfs_remove(rfcomm_sock_debugfs);
1072 
1073 	if (bt_sock_unregister(BTPROTO_RFCOMM) < 0)
1074 		BT_ERR("RFCOMM socket layer unregistration failed");
1075 
1076 	proto_unregister(&rfcomm_proto);
1077 }
1078