xref: /linux/net/bluetooth/rfcomm/sock.c (revision 092e0e7e520a1fca03e13c9f2d157432a8657ff2)
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 <net/sock.h>
46 
47 #include <asm/system.h>
48 #include <asm/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 	sk_for_each(sk, node, &rfcomm_sk_list.head) {
149 		if (state && sk->sk_state != state)
150 			continue;
151 
152 		if (rfcomm_pi(sk)->channel == channel) {
153 			/* Exact match. */
154 			if (!bacmp(&bt_sk(sk)->src, src))
155 				break;
156 
157 			/* Closest match */
158 			if (!bacmp(&bt_sk(sk)->src, BDADDR_ANY))
159 				sk1 = sk;
160 		}
161 	}
162 	return node ? sk : sk1;
163 }
164 
165 /* Find socket with given address (channel, src).
166  * Returns locked socket */
167 static inline struct sock *rfcomm_get_sock_by_channel(int state, u8 channel, bdaddr_t *src)
168 {
169 	struct sock *s;
170 	read_lock(&rfcomm_sk_list.lock);
171 	s = __rfcomm_get_sock_by_channel(state, channel, src);
172 	if (s) bh_lock_sock(s);
173 	read_unlock(&rfcomm_sk_list.lock);
174 	return s;
175 }
176 
177 static void rfcomm_sock_destruct(struct sock *sk)
178 {
179 	struct rfcomm_dlc *d = rfcomm_pi(sk)->dlc;
180 
181 	BT_DBG("sk %p dlc %p", sk, d);
182 
183 	skb_queue_purge(&sk->sk_receive_queue);
184 	skb_queue_purge(&sk->sk_write_queue);
185 
186 	rfcomm_dlc_lock(d);
187 	rfcomm_pi(sk)->dlc = NULL;
188 
189 	/* Detach DLC if it's owned by this socket */
190 	if (d->owner == sk)
191 		d->owner = NULL;
192 	rfcomm_dlc_unlock(d);
193 
194 	rfcomm_dlc_put(d);
195 }
196 
197 static void rfcomm_sock_cleanup_listen(struct sock *parent)
198 {
199 	struct sock *sk;
200 
201 	BT_DBG("parent %p", parent);
202 
203 	/* Close not yet accepted dlcs */
204 	while ((sk = bt_accept_dequeue(parent, NULL))) {
205 		rfcomm_sock_close(sk);
206 		rfcomm_sock_kill(sk);
207 	}
208 
209 	parent->sk_state  = BT_CLOSED;
210 	sock_set_flag(parent, SOCK_ZAPPED);
211 }
212 
213 /* Kill socket (only if zapped and orphan)
214  * Must be called on unlocked socket.
215  */
216 static void rfcomm_sock_kill(struct sock *sk)
217 {
218 	if (!sock_flag(sk, SOCK_ZAPPED) || sk->sk_socket)
219 		return;
220 
221 	BT_DBG("sk %p state %d refcnt %d", sk, sk->sk_state, atomic_read(&sk->sk_refcnt));
222 
223 	/* Kill poor orphan */
224 	bt_sock_unlink(&rfcomm_sk_list, sk);
225 	sock_set_flag(sk, SOCK_DEAD);
226 	sock_put(sk);
227 }
228 
229 static void __rfcomm_sock_close(struct sock *sk)
230 {
231 	struct rfcomm_dlc *d = rfcomm_pi(sk)->dlc;
232 
233 	BT_DBG("sk %p state %d socket %p", sk, sk->sk_state, sk->sk_socket);
234 
235 	switch (sk->sk_state) {
236 	case BT_LISTEN:
237 		rfcomm_sock_cleanup_listen(sk);
238 		break;
239 
240 	case BT_CONNECT:
241 	case BT_CONNECT2:
242 	case BT_CONFIG:
243 	case BT_CONNECTED:
244 		rfcomm_dlc_close(d, 0);
245 
246 	default:
247 		sock_set_flag(sk, SOCK_ZAPPED);
248 		break;
249 	}
250 }
251 
252 /* Close socket.
253  * Must be called on unlocked socket.
254  */
255 static void rfcomm_sock_close(struct sock *sk)
256 {
257 	lock_sock(sk);
258 	__rfcomm_sock_close(sk);
259 	release_sock(sk);
260 }
261 
262 static void rfcomm_sock_init(struct sock *sk, struct sock *parent)
263 {
264 	struct rfcomm_pinfo *pi = rfcomm_pi(sk);
265 
266 	BT_DBG("sk %p", sk);
267 
268 	if (parent) {
269 		sk->sk_type = parent->sk_type;
270 		pi->dlc->defer_setup = bt_sk(parent)->defer_setup;
271 
272 		pi->sec_level = rfcomm_pi(parent)->sec_level;
273 		pi->role_switch = rfcomm_pi(parent)->role_switch;
274 	} else {
275 		pi->dlc->defer_setup = 0;
276 
277 		pi->sec_level = BT_SECURITY_LOW;
278 		pi->role_switch = 0;
279 	}
280 
281 	pi->dlc->sec_level = pi->sec_level;
282 	pi->dlc->role_switch = pi->role_switch;
283 }
284 
285 static struct proto rfcomm_proto = {
286 	.name		= "RFCOMM",
287 	.owner		= THIS_MODULE,
288 	.obj_size	= sizeof(struct rfcomm_pinfo)
289 };
290 
291 static struct sock *rfcomm_sock_alloc(struct net *net, struct socket *sock, int proto, gfp_t prio)
292 {
293 	struct rfcomm_dlc *d;
294 	struct sock *sk;
295 
296 	sk = sk_alloc(net, PF_BLUETOOTH, prio, &rfcomm_proto);
297 	if (!sk)
298 		return NULL;
299 
300 	sock_init_data(sock, sk);
301 	INIT_LIST_HEAD(&bt_sk(sk)->accept_q);
302 
303 	d = rfcomm_dlc_alloc(prio);
304 	if (!d) {
305 		sk_free(sk);
306 		return NULL;
307 	}
308 
309 	d->data_ready   = rfcomm_sk_data_ready;
310 	d->state_change = rfcomm_sk_state_change;
311 
312 	rfcomm_pi(sk)->dlc = d;
313 	d->owner = sk;
314 
315 	sk->sk_destruct = rfcomm_sock_destruct;
316 	sk->sk_sndtimeo = RFCOMM_CONN_TIMEOUT;
317 
318 	sk->sk_sndbuf = RFCOMM_MAX_CREDITS * RFCOMM_DEFAULT_MTU * 10;
319 	sk->sk_rcvbuf = RFCOMM_MAX_CREDITS * RFCOMM_DEFAULT_MTU * 10;
320 
321 	sock_reset_flag(sk, SOCK_ZAPPED);
322 
323 	sk->sk_protocol = proto;
324 	sk->sk_state    = BT_OPEN;
325 
326 	bt_sock_link(&rfcomm_sk_list, sk);
327 
328 	BT_DBG("sk %p", sk);
329 	return sk;
330 }
331 
332 static int rfcomm_sock_create(struct net *net, struct socket *sock,
333 			      int protocol, int kern)
334 {
335 	struct sock *sk;
336 
337 	BT_DBG("sock %p", sock);
338 
339 	sock->state = SS_UNCONNECTED;
340 
341 	if (sock->type != SOCK_STREAM && sock->type != SOCK_RAW)
342 		return -ESOCKTNOSUPPORT;
343 
344 	sock->ops = &rfcomm_sock_ops;
345 
346 	sk = rfcomm_sock_alloc(net, sock, protocol, GFP_ATOMIC);
347 	if (!sk)
348 		return -ENOMEM;
349 
350 	rfcomm_sock_init(sk, NULL);
351 	return 0;
352 }
353 
354 static int rfcomm_sock_bind(struct socket *sock, struct sockaddr *addr, int addr_len)
355 {
356 	struct sockaddr_rc *sa = (struct sockaddr_rc *) addr;
357 	struct sock *sk = sock->sk;
358 	int err = 0;
359 
360 	BT_DBG("sk %p %s", sk, batostr(&sa->rc_bdaddr));
361 
362 	if (!addr || addr->sa_family != AF_BLUETOOTH)
363 		return -EINVAL;
364 
365 	lock_sock(sk);
366 
367 	if (sk->sk_state != BT_OPEN) {
368 		err = -EBADFD;
369 		goto done;
370 	}
371 
372 	if (sk->sk_type != SOCK_STREAM) {
373 		err = -EINVAL;
374 		goto done;
375 	}
376 
377 	write_lock_bh(&rfcomm_sk_list.lock);
378 
379 	if (sa->rc_channel && __rfcomm_get_sock_by_addr(sa->rc_channel, &sa->rc_bdaddr)) {
380 		err = -EADDRINUSE;
381 	} else {
382 		/* Save source address */
383 		bacpy(&bt_sk(sk)->src, &sa->rc_bdaddr);
384 		rfcomm_pi(sk)->channel = sa->rc_channel;
385 		sk->sk_state = BT_BOUND;
386 	}
387 
388 	write_unlock_bh(&rfcomm_sk_list.lock);
389 
390 done:
391 	release_sock(sk);
392 	return err;
393 }
394 
395 static int rfcomm_sock_connect(struct socket *sock, struct sockaddr *addr, int alen, int flags)
396 {
397 	struct sockaddr_rc *sa = (struct sockaddr_rc *) addr;
398 	struct sock *sk = sock->sk;
399 	struct rfcomm_dlc *d = rfcomm_pi(sk)->dlc;
400 	int err = 0;
401 
402 	BT_DBG("sk %p", sk);
403 
404 	if (alen < sizeof(struct sockaddr_rc) ||
405 	    addr->sa_family != AF_BLUETOOTH)
406 		return -EINVAL;
407 
408 	lock_sock(sk);
409 
410 	if (sk->sk_state != BT_OPEN && sk->sk_state != BT_BOUND) {
411 		err = -EBADFD;
412 		goto done;
413 	}
414 
415 	if (sk->sk_type != SOCK_STREAM) {
416 		err = -EINVAL;
417 		goto done;
418 	}
419 
420 	sk->sk_state = BT_CONNECT;
421 	bacpy(&bt_sk(sk)->dst, &sa->rc_bdaddr);
422 	rfcomm_pi(sk)->channel = sa->rc_channel;
423 
424 	d->sec_level = rfcomm_pi(sk)->sec_level;
425 	d->role_switch = rfcomm_pi(sk)->role_switch;
426 
427 	err = rfcomm_dlc_open(d, &bt_sk(sk)->src, &sa->rc_bdaddr, sa->rc_channel);
428 	if (!err)
429 		err = bt_sock_wait_state(sk, BT_CONNECTED,
430 				sock_sndtimeo(sk, flags & O_NONBLOCK));
431 
432 done:
433 	release_sock(sk);
434 	return err;
435 }
436 
437 static int rfcomm_sock_listen(struct socket *sock, int backlog)
438 {
439 	struct sock *sk = sock->sk;
440 	int err = 0;
441 
442 	BT_DBG("sk %p backlog %d", sk, backlog);
443 
444 	lock_sock(sk);
445 
446 	if (sk->sk_state != BT_BOUND) {
447 		err = -EBADFD;
448 		goto done;
449 	}
450 
451 	if (sk->sk_type != SOCK_STREAM) {
452 		err = -EINVAL;
453 		goto done;
454 	}
455 
456 	if (!rfcomm_pi(sk)->channel) {
457 		bdaddr_t *src = &bt_sk(sk)->src;
458 		u8 channel;
459 
460 		err = -EINVAL;
461 
462 		write_lock_bh(&rfcomm_sk_list.lock);
463 
464 		for (channel = 1; channel < 31; channel++)
465 			if (!__rfcomm_get_sock_by_addr(channel, src)) {
466 				rfcomm_pi(sk)->channel = channel;
467 				err = 0;
468 				break;
469 			}
470 
471 		write_unlock_bh(&rfcomm_sk_list.lock);
472 
473 		if (err < 0)
474 			goto done;
475 	}
476 
477 	sk->sk_max_ack_backlog = backlog;
478 	sk->sk_ack_backlog = 0;
479 	sk->sk_state = BT_LISTEN;
480 
481 done:
482 	release_sock(sk);
483 	return err;
484 }
485 
486 static int rfcomm_sock_accept(struct socket *sock, struct socket *newsock, int flags)
487 {
488 	DECLARE_WAITQUEUE(wait, current);
489 	struct sock *sk = sock->sk, *nsk;
490 	long timeo;
491 	int err = 0;
492 
493 	lock_sock(sk);
494 
495 	if (sk->sk_state != BT_LISTEN) {
496 		err = -EBADFD;
497 		goto done;
498 	}
499 
500 	if (sk->sk_type != SOCK_STREAM) {
501 		err = -EINVAL;
502 		goto done;
503 	}
504 
505 	timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
506 
507 	BT_DBG("sk %p timeo %ld", sk, timeo);
508 
509 	/* Wait for an incoming connection. (wake-one). */
510 	add_wait_queue_exclusive(sk_sleep(sk), &wait);
511 	while (!(nsk = bt_accept_dequeue(sk, newsock))) {
512 		set_current_state(TASK_INTERRUPTIBLE);
513 		if (!timeo) {
514 			err = -EAGAIN;
515 			break;
516 		}
517 
518 		release_sock(sk);
519 		timeo = schedule_timeout(timeo);
520 		lock_sock(sk);
521 
522 		if (sk->sk_state != BT_LISTEN) {
523 			err = -EBADFD;
524 			break;
525 		}
526 
527 		if (signal_pending(current)) {
528 			err = sock_intr_errno(timeo);
529 			break;
530 		}
531 	}
532 	set_current_state(TASK_RUNNING);
533 	remove_wait_queue(sk_sleep(sk), &wait);
534 
535 	if (err)
536 		goto done;
537 
538 	newsock->state = SS_CONNECTED;
539 
540 	BT_DBG("new socket %p", nsk);
541 
542 done:
543 	release_sock(sk);
544 	return err;
545 }
546 
547 static int rfcomm_sock_getname(struct socket *sock, struct sockaddr *addr, int *len, int peer)
548 {
549 	struct sockaddr_rc *sa = (struct sockaddr_rc *) addr;
550 	struct sock *sk = sock->sk;
551 
552 	BT_DBG("sock %p, sk %p", sock, sk);
553 
554 	sa->rc_family  = AF_BLUETOOTH;
555 	sa->rc_channel = rfcomm_pi(sk)->channel;
556 	if (peer)
557 		bacpy(&sa->rc_bdaddr, &bt_sk(sk)->dst);
558 	else
559 		bacpy(&sa->rc_bdaddr, &bt_sk(sk)->src);
560 
561 	*len = sizeof(struct sockaddr_rc);
562 	return 0;
563 }
564 
565 static int rfcomm_sock_sendmsg(struct kiocb *iocb, struct socket *sock,
566 			       struct msghdr *msg, size_t len)
567 {
568 	struct sock *sk = sock->sk;
569 	struct rfcomm_dlc *d = rfcomm_pi(sk)->dlc;
570 	struct sk_buff *skb;
571 	int sent = 0;
572 
573 	if (test_bit(RFCOMM_DEFER_SETUP, &d->flags))
574 		return -ENOTCONN;
575 
576 	if (msg->msg_flags & MSG_OOB)
577 		return -EOPNOTSUPP;
578 
579 	if (sk->sk_shutdown & SEND_SHUTDOWN)
580 		return -EPIPE;
581 
582 	BT_DBG("sock %p, sk %p", sock, sk);
583 
584 	lock_sock(sk);
585 
586 	while (len) {
587 		size_t size = min_t(size_t, len, d->mtu);
588 		int err;
589 
590 		skb = sock_alloc_send_skb(sk, size + RFCOMM_SKB_RESERVE,
591 				msg->msg_flags & MSG_DONTWAIT, &err);
592 		if (!skb) {
593 			if (sent == 0)
594 				sent = err;
595 			break;
596 		}
597 		skb_reserve(skb, RFCOMM_SKB_HEAD_RESERVE);
598 
599 		err = memcpy_fromiovec(skb_put(skb, size), msg->msg_iov, size);
600 		if (err) {
601 			kfree_skb(skb);
602 			if (sent == 0)
603 				sent = err;
604 			break;
605 		}
606 
607 		err = rfcomm_dlc_send(d, skb);
608 		if (err < 0) {
609 			kfree_skb(skb);
610 			if (sent == 0)
611 				sent = err;
612 			break;
613 		}
614 
615 		sent += size;
616 		len  -= size;
617 	}
618 
619 	release_sock(sk);
620 
621 	return sent;
622 }
623 
624 static long rfcomm_sock_data_wait(struct sock *sk, long timeo)
625 {
626 	DECLARE_WAITQUEUE(wait, current);
627 
628 	add_wait_queue(sk_sleep(sk), &wait);
629 	for (;;) {
630 		set_current_state(TASK_INTERRUPTIBLE);
631 
632 		if (!skb_queue_empty(&sk->sk_receive_queue) ||
633 		    sk->sk_err ||
634 		    (sk->sk_shutdown & RCV_SHUTDOWN) ||
635 		    signal_pending(current) ||
636 		    !timeo)
637 			break;
638 
639 		set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
640 		release_sock(sk);
641 		timeo = schedule_timeout(timeo);
642 		lock_sock(sk);
643 		clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
644 	}
645 
646 	__set_current_state(TASK_RUNNING);
647 	remove_wait_queue(sk_sleep(sk), &wait);
648 	return timeo;
649 }
650 
651 static int rfcomm_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
652 			       struct msghdr *msg, size_t size, int flags)
653 {
654 	struct sock *sk = sock->sk;
655 	struct rfcomm_dlc *d = rfcomm_pi(sk)->dlc;
656 	int err = 0;
657 	size_t target, copied = 0;
658 	long timeo;
659 
660 	if (test_and_clear_bit(RFCOMM_DEFER_SETUP, &d->flags)) {
661 		rfcomm_dlc_accept(d);
662 		return 0;
663 	}
664 
665 	if (flags & MSG_OOB)
666 		return -EOPNOTSUPP;
667 
668 	msg->msg_namelen = 0;
669 
670 	BT_DBG("sk %p size %zu", sk, size);
671 
672 	lock_sock(sk);
673 
674 	target = sock_rcvlowat(sk, flags & MSG_WAITALL, size);
675 	timeo  = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
676 
677 	do {
678 		struct sk_buff *skb;
679 		int chunk;
680 
681 		skb = skb_dequeue(&sk->sk_receive_queue);
682 		if (!skb) {
683 			if (copied >= target)
684 				break;
685 
686 			if ((err = sock_error(sk)) != 0)
687 				break;
688 			if (sk->sk_shutdown & RCV_SHUTDOWN)
689 				break;
690 
691 			err = -EAGAIN;
692 			if (!timeo)
693 				break;
694 
695 			timeo = rfcomm_sock_data_wait(sk, timeo);
696 
697 			if (signal_pending(current)) {
698 				err = sock_intr_errno(timeo);
699 				goto out;
700 			}
701 			continue;
702 		}
703 
704 		chunk = min_t(unsigned int, skb->len, size);
705 		if (memcpy_toiovec(msg->msg_iov, skb->data, chunk)) {
706 			skb_queue_head(&sk->sk_receive_queue, skb);
707 			if (!copied)
708 				copied = -EFAULT;
709 			break;
710 		}
711 		copied += chunk;
712 		size   -= chunk;
713 
714 		sock_recv_ts_and_drops(msg, sk, skb);
715 
716 		if (!(flags & MSG_PEEK)) {
717 			atomic_sub(chunk, &sk->sk_rmem_alloc);
718 
719 			skb_pull(skb, chunk);
720 			if (skb->len) {
721 				skb_queue_head(&sk->sk_receive_queue, skb);
722 				break;
723 			}
724 			kfree_skb(skb);
725 
726 		} else {
727 			/* put message back and return */
728 			skb_queue_head(&sk->sk_receive_queue, skb);
729 			break;
730 		}
731 	} while (size);
732 
733 out:
734 	if (atomic_read(&sk->sk_rmem_alloc) <= (sk->sk_rcvbuf >> 2))
735 		rfcomm_dlc_unthrottle(rfcomm_pi(sk)->dlc);
736 
737 	release_sock(sk);
738 	return copied ? : err;
739 }
740 
741 static int rfcomm_sock_setsockopt_old(struct socket *sock, int optname, char __user *optval, unsigned int optlen)
742 {
743 	struct sock *sk = sock->sk;
744 	int err = 0;
745 	u32 opt;
746 
747 	BT_DBG("sk %p", sk);
748 
749 	lock_sock(sk);
750 
751 	switch (optname) {
752 	case RFCOMM_LM:
753 		if (get_user(opt, (u32 __user *) optval)) {
754 			err = -EFAULT;
755 			break;
756 		}
757 
758 		if (opt & RFCOMM_LM_AUTH)
759 			rfcomm_pi(sk)->sec_level = BT_SECURITY_LOW;
760 		if (opt & RFCOMM_LM_ENCRYPT)
761 			rfcomm_pi(sk)->sec_level = BT_SECURITY_MEDIUM;
762 		if (opt & RFCOMM_LM_SECURE)
763 			rfcomm_pi(sk)->sec_level = BT_SECURITY_HIGH;
764 
765 		rfcomm_pi(sk)->role_switch = (opt & RFCOMM_LM_MASTER);
766 		break;
767 
768 	default:
769 		err = -ENOPROTOOPT;
770 		break;
771 	}
772 
773 	release_sock(sk);
774 	return err;
775 }
776 
777 static int rfcomm_sock_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen)
778 {
779 	struct sock *sk = sock->sk;
780 	struct bt_security sec;
781 	int len, err = 0;
782 	u32 opt;
783 
784 	BT_DBG("sk %p", sk);
785 
786 	if (level == SOL_RFCOMM)
787 		return rfcomm_sock_setsockopt_old(sock, optname, optval, optlen);
788 
789 	if (level != SOL_BLUETOOTH)
790 		return -ENOPROTOOPT;
791 
792 	lock_sock(sk);
793 
794 	switch (optname) {
795 	case BT_SECURITY:
796 		if (sk->sk_type != SOCK_STREAM) {
797 			err = -EINVAL;
798 			break;
799 		}
800 
801 		sec.level = BT_SECURITY_LOW;
802 
803 		len = min_t(unsigned int, sizeof(sec), optlen);
804 		if (copy_from_user((char *) &sec, optval, len)) {
805 			err = -EFAULT;
806 			break;
807 		}
808 
809 		if (sec.level > BT_SECURITY_HIGH) {
810 			err = -EINVAL;
811 			break;
812 		}
813 
814 		rfcomm_pi(sk)->sec_level = sec.level;
815 		break;
816 
817 	case BT_DEFER_SETUP:
818 		if (sk->sk_state != BT_BOUND && sk->sk_state != BT_LISTEN) {
819 			err = -EINVAL;
820 			break;
821 		}
822 
823 		if (get_user(opt, (u32 __user *) optval)) {
824 			err = -EFAULT;
825 			break;
826 		}
827 
828 		bt_sk(sk)->defer_setup = opt;
829 		break;
830 
831 	default:
832 		err = -ENOPROTOOPT;
833 		break;
834 	}
835 
836 	release_sock(sk);
837 	return err;
838 }
839 
840 static int rfcomm_sock_getsockopt_old(struct socket *sock, int optname, char __user *optval, int __user *optlen)
841 {
842 	struct sock *sk = sock->sk;
843 	struct sock *l2cap_sk;
844 	struct rfcomm_conninfo cinfo;
845 	int len, err = 0;
846 	u32 opt;
847 
848 	BT_DBG("sk %p", sk);
849 
850 	if (get_user(len, optlen))
851 		return -EFAULT;
852 
853 	lock_sock(sk);
854 
855 	switch (optname) {
856 	case RFCOMM_LM:
857 		switch (rfcomm_pi(sk)->sec_level) {
858 		case BT_SECURITY_LOW:
859 			opt = RFCOMM_LM_AUTH;
860 			break;
861 		case BT_SECURITY_MEDIUM:
862 			opt = RFCOMM_LM_AUTH | RFCOMM_LM_ENCRYPT;
863 			break;
864 		case BT_SECURITY_HIGH:
865 			opt = RFCOMM_LM_AUTH | RFCOMM_LM_ENCRYPT |
866 							RFCOMM_LM_SECURE;
867 			break;
868 		default:
869 			opt = 0;
870 			break;
871 		}
872 
873 		if (rfcomm_pi(sk)->role_switch)
874 			opt |= RFCOMM_LM_MASTER;
875 
876 		if (put_user(opt, (u32 __user *) optval))
877 			err = -EFAULT;
878 		break;
879 
880 	case RFCOMM_CONNINFO:
881 		if (sk->sk_state != BT_CONNECTED &&
882 					!rfcomm_pi(sk)->dlc->defer_setup) {
883 			err = -ENOTCONN;
884 			break;
885 		}
886 
887 		l2cap_sk = rfcomm_pi(sk)->dlc->session->sock->sk;
888 
889 		cinfo.hci_handle = l2cap_pi(l2cap_sk)->conn->hcon->handle;
890 		memcpy(cinfo.dev_class, l2cap_pi(l2cap_sk)->conn->hcon->dev_class, 3);
891 
892 		len = min_t(unsigned int, len, sizeof(cinfo));
893 		if (copy_to_user(optval, (char *) &cinfo, len))
894 			err = -EFAULT;
895 
896 		break;
897 
898 	default:
899 		err = -ENOPROTOOPT;
900 		break;
901 	}
902 
903 	release_sock(sk);
904 	return err;
905 }
906 
907 static int rfcomm_sock_getsockopt(struct socket *sock, int level, int optname, char __user *optval, int __user *optlen)
908 {
909 	struct sock *sk = sock->sk;
910 	struct bt_security sec;
911 	int len, err = 0;
912 
913 	BT_DBG("sk %p", sk);
914 
915 	if (level == SOL_RFCOMM)
916 		return rfcomm_sock_getsockopt_old(sock, optname, optval, optlen);
917 
918 	if (level != SOL_BLUETOOTH)
919 		return -ENOPROTOOPT;
920 
921 	if (get_user(len, optlen))
922 		return -EFAULT;
923 
924 	lock_sock(sk);
925 
926 	switch (optname) {
927 	case BT_SECURITY:
928 		if (sk->sk_type != SOCK_STREAM) {
929 			err = -EINVAL;
930 			break;
931 		}
932 
933 		sec.level = rfcomm_pi(sk)->sec_level;
934 
935 		len = min_t(unsigned int, len, sizeof(sec));
936 		if (copy_to_user(optval, (char *) &sec, len))
937 			err = -EFAULT;
938 
939 		break;
940 
941 	case BT_DEFER_SETUP:
942 		if (sk->sk_state != BT_BOUND && sk->sk_state != BT_LISTEN) {
943 			err = -EINVAL;
944 			break;
945 		}
946 
947 		if (put_user(bt_sk(sk)->defer_setup, (u32 __user *) optval))
948 			err = -EFAULT;
949 
950 		break;
951 
952 	default:
953 		err = -ENOPROTOOPT;
954 		break;
955 	}
956 
957 	release_sock(sk);
958 	return err;
959 }
960 
961 static int rfcomm_sock_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
962 {
963 	struct sock *sk __maybe_unused = sock->sk;
964 	int err;
965 
966 	BT_DBG("sk %p cmd %x arg %lx", sk, cmd, arg);
967 
968 	err = bt_sock_ioctl(sock, cmd, arg);
969 
970 	if (err == -ENOIOCTLCMD) {
971 #ifdef CONFIG_BT_RFCOMM_TTY
972 		lock_sock(sk);
973 		err = rfcomm_dev_ioctl(sk, cmd, (void __user *) arg);
974 		release_sock(sk);
975 #else
976 		err = -EOPNOTSUPP;
977 #endif
978 	}
979 
980 	return err;
981 }
982 
983 static int rfcomm_sock_shutdown(struct socket *sock, int how)
984 {
985 	struct sock *sk = sock->sk;
986 	int err = 0;
987 
988 	BT_DBG("sock %p, sk %p", sock, sk);
989 
990 	if (!sk) return 0;
991 
992 	lock_sock(sk);
993 	if (!sk->sk_shutdown) {
994 		sk->sk_shutdown = SHUTDOWN_MASK;
995 		__rfcomm_sock_close(sk);
996 
997 		if (sock_flag(sk, SOCK_LINGER) && sk->sk_lingertime)
998 			err = bt_sock_wait_state(sk, BT_CLOSED, sk->sk_lingertime);
999 	}
1000 	release_sock(sk);
1001 	return err;
1002 }
1003 
1004 static int rfcomm_sock_release(struct socket *sock)
1005 {
1006 	struct sock *sk = sock->sk;
1007 	int err;
1008 
1009 	BT_DBG("sock %p, sk %p", sock, sk);
1010 
1011 	if (!sk)
1012 		return 0;
1013 
1014 	err = rfcomm_sock_shutdown(sock, 2);
1015 
1016 	sock_orphan(sk);
1017 	rfcomm_sock_kill(sk);
1018 	return err;
1019 }
1020 
1021 /* ---- RFCOMM core layer callbacks ----
1022  *
1023  * called under rfcomm_lock()
1024  */
1025 int rfcomm_connect_ind(struct rfcomm_session *s, u8 channel, struct rfcomm_dlc **d)
1026 {
1027 	struct sock *sk, *parent;
1028 	bdaddr_t src, dst;
1029 	int result = 0;
1030 
1031 	BT_DBG("session %p channel %d", s, channel);
1032 
1033 	rfcomm_session_getaddr(s, &src, &dst);
1034 
1035 	/* Check if we have socket listening on channel */
1036 	parent = rfcomm_get_sock_by_channel(BT_LISTEN, channel, &src);
1037 	if (!parent)
1038 		return 0;
1039 
1040 	/* Check for backlog size */
1041 	if (sk_acceptq_is_full(parent)) {
1042 		BT_DBG("backlog full %d", parent->sk_ack_backlog);
1043 		goto done;
1044 	}
1045 
1046 	sk = rfcomm_sock_alloc(sock_net(parent), NULL, BTPROTO_RFCOMM, GFP_ATOMIC);
1047 	if (!sk)
1048 		goto done;
1049 
1050 	rfcomm_sock_init(sk, parent);
1051 	bacpy(&bt_sk(sk)->src, &src);
1052 	bacpy(&bt_sk(sk)->dst, &dst);
1053 	rfcomm_pi(sk)->channel = channel;
1054 
1055 	sk->sk_state = BT_CONFIG;
1056 	bt_accept_enqueue(parent, sk);
1057 
1058 	/* Accept connection and return socket DLC */
1059 	*d = rfcomm_pi(sk)->dlc;
1060 	result = 1;
1061 
1062 done:
1063 	bh_unlock_sock(parent);
1064 
1065 	if (bt_sk(parent)->defer_setup)
1066 		parent->sk_state_change(parent);
1067 
1068 	return result;
1069 }
1070 
1071 static int rfcomm_sock_debugfs_show(struct seq_file *f, void *p)
1072 {
1073 	struct sock *sk;
1074 	struct hlist_node *node;
1075 
1076 	read_lock_bh(&rfcomm_sk_list.lock);
1077 
1078 	sk_for_each(sk, node, &rfcomm_sk_list.head) {
1079 		seq_printf(f, "%s %s %d %d\n",
1080 				batostr(&bt_sk(sk)->src),
1081 				batostr(&bt_sk(sk)->dst),
1082 				sk->sk_state, rfcomm_pi(sk)->channel);
1083 	}
1084 
1085 	read_unlock_bh(&rfcomm_sk_list.lock);
1086 
1087 	return 0;
1088 }
1089 
1090 static int rfcomm_sock_debugfs_open(struct inode *inode, struct file *file)
1091 {
1092 	return single_open(file, rfcomm_sock_debugfs_show, inode->i_private);
1093 }
1094 
1095 static const struct file_operations rfcomm_sock_debugfs_fops = {
1096 	.open		= rfcomm_sock_debugfs_open,
1097 	.read		= seq_read,
1098 	.llseek		= seq_lseek,
1099 	.release	= single_release,
1100 };
1101 
1102 static struct dentry *rfcomm_sock_debugfs;
1103 
1104 static const struct proto_ops rfcomm_sock_ops = {
1105 	.family		= PF_BLUETOOTH,
1106 	.owner		= THIS_MODULE,
1107 	.release	= rfcomm_sock_release,
1108 	.bind		= rfcomm_sock_bind,
1109 	.connect	= rfcomm_sock_connect,
1110 	.listen		= rfcomm_sock_listen,
1111 	.accept		= rfcomm_sock_accept,
1112 	.getname	= rfcomm_sock_getname,
1113 	.sendmsg	= rfcomm_sock_sendmsg,
1114 	.recvmsg	= rfcomm_sock_recvmsg,
1115 	.shutdown	= rfcomm_sock_shutdown,
1116 	.setsockopt	= rfcomm_sock_setsockopt,
1117 	.getsockopt	= rfcomm_sock_getsockopt,
1118 	.ioctl		= rfcomm_sock_ioctl,
1119 	.poll		= bt_sock_poll,
1120 	.socketpair	= sock_no_socketpair,
1121 	.mmap		= sock_no_mmap
1122 };
1123 
1124 static const struct net_proto_family rfcomm_sock_family_ops = {
1125 	.family		= PF_BLUETOOTH,
1126 	.owner		= THIS_MODULE,
1127 	.create		= rfcomm_sock_create
1128 };
1129 
1130 int __init rfcomm_init_sockets(void)
1131 {
1132 	int err;
1133 
1134 	err = proto_register(&rfcomm_proto, 0);
1135 	if (err < 0)
1136 		return err;
1137 
1138 	err = bt_sock_register(BTPROTO_RFCOMM, &rfcomm_sock_family_ops);
1139 	if (err < 0)
1140 		goto error;
1141 
1142 	if (bt_debugfs) {
1143 		rfcomm_sock_debugfs = debugfs_create_file("rfcomm", 0444,
1144 				bt_debugfs, NULL, &rfcomm_sock_debugfs_fops);
1145 		if (!rfcomm_sock_debugfs)
1146 			BT_ERR("Failed to create RFCOMM debug file");
1147 	}
1148 
1149 	BT_INFO("RFCOMM socket layer initialized");
1150 
1151 	return 0;
1152 
1153 error:
1154 	BT_ERR("RFCOMM socket layer registration failed");
1155 	proto_unregister(&rfcomm_proto);
1156 	return err;
1157 }
1158 
1159 void __exit rfcomm_cleanup_sockets(void)
1160 {
1161 	debugfs_remove(rfcomm_sock_debugfs);
1162 
1163 	if (bt_sock_unregister(BTPROTO_RFCOMM) < 0)
1164 		BT_ERR("RFCOMM socket layer unregistration failed");
1165 
1166 	proto_unregister(&rfcomm_proto);
1167 }
1168