xref: /linux/net/bluetooth/rfcomm/sock.c (revision cb299ba8b5ef2239429484072fea394cd7581bd7)
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 int rfcomm_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
625 			       struct msghdr *msg, size_t size, int flags)
626 {
627 	struct sock *sk = sock->sk;
628 	struct rfcomm_dlc *d = rfcomm_pi(sk)->dlc;
629 	int len;
630 
631 	if (test_and_clear_bit(RFCOMM_DEFER_SETUP, &d->flags)) {
632 		rfcomm_dlc_accept(d);
633 		return 0;
634 	}
635 
636 	len = bt_sock_stream_recvmsg(iocb, sock, msg, size, flags);
637 
638 	lock_sock(sk);
639 	if (!(flags & MSG_PEEK) && len > 0)
640 		atomic_sub(len, &sk->sk_rmem_alloc);
641 
642 	if (atomic_read(&sk->sk_rmem_alloc) <= (sk->sk_rcvbuf >> 2))
643 		rfcomm_dlc_unthrottle(rfcomm_pi(sk)->dlc);
644 	release_sock(sk);
645 
646 	return len;
647 }
648 
649 static int rfcomm_sock_setsockopt_old(struct socket *sock, int optname, char __user *optval, unsigned int optlen)
650 {
651 	struct sock *sk = sock->sk;
652 	int err = 0;
653 	u32 opt;
654 
655 	BT_DBG("sk %p", sk);
656 
657 	lock_sock(sk);
658 
659 	switch (optname) {
660 	case RFCOMM_LM:
661 		if (get_user(opt, (u32 __user *) optval)) {
662 			err = -EFAULT;
663 			break;
664 		}
665 
666 		if (opt & RFCOMM_LM_AUTH)
667 			rfcomm_pi(sk)->sec_level = BT_SECURITY_LOW;
668 		if (opt & RFCOMM_LM_ENCRYPT)
669 			rfcomm_pi(sk)->sec_level = BT_SECURITY_MEDIUM;
670 		if (opt & RFCOMM_LM_SECURE)
671 			rfcomm_pi(sk)->sec_level = BT_SECURITY_HIGH;
672 
673 		rfcomm_pi(sk)->role_switch = (opt & RFCOMM_LM_MASTER);
674 		break;
675 
676 	default:
677 		err = -ENOPROTOOPT;
678 		break;
679 	}
680 
681 	release_sock(sk);
682 	return err;
683 }
684 
685 static int rfcomm_sock_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen)
686 {
687 	struct sock *sk = sock->sk;
688 	struct bt_security sec;
689 	int len, err = 0;
690 	u32 opt;
691 
692 	BT_DBG("sk %p", sk);
693 
694 	if (level == SOL_RFCOMM)
695 		return rfcomm_sock_setsockopt_old(sock, optname, optval, optlen);
696 
697 	if (level != SOL_BLUETOOTH)
698 		return -ENOPROTOOPT;
699 
700 	lock_sock(sk);
701 
702 	switch (optname) {
703 	case BT_SECURITY:
704 		if (sk->sk_type != SOCK_STREAM) {
705 			err = -EINVAL;
706 			break;
707 		}
708 
709 		sec.level = BT_SECURITY_LOW;
710 
711 		len = min_t(unsigned int, sizeof(sec), optlen);
712 		if (copy_from_user((char *) &sec, optval, len)) {
713 			err = -EFAULT;
714 			break;
715 		}
716 
717 		if (sec.level > BT_SECURITY_HIGH) {
718 			err = -EINVAL;
719 			break;
720 		}
721 
722 		rfcomm_pi(sk)->sec_level = sec.level;
723 		break;
724 
725 	case BT_DEFER_SETUP:
726 		if (sk->sk_state != BT_BOUND && sk->sk_state != BT_LISTEN) {
727 			err = -EINVAL;
728 			break;
729 		}
730 
731 		if (get_user(opt, (u32 __user *) optval)) {
732 			err = -EFAULT;
733 			break;
734 		}
735 
736 		bt_sk(sk)->defer_setup = opt;
737 		break;
738 
739 	default:
740 		err = -ENOPROTOOPT;
741 		break;
742 	}
743 
744 	release_sock(sk);
745 	return err;
746 }
747 
748 static int rfcomm_sock_getsockopt_old(struct socket *sock, int optname, char __user *optval, int __user *optlen)
749 {
750 	struct sock *sk = sock->sk;
751 	struct sock *l2cap_sk;
752 	struct rfcomm_conninfo cinfo;
753 	int len, err = 0;
754 	u32 opt;
755 
756 	BT_DBG("sk %p", sk);
757 
758 	if (get_user(len, optlen))
759 		return -EFAULT;
760 
761 	lock_sock(sk);
762 
763 	switch (optname) {
764 	case RFCOMM_LM:
765 		switch (rfcomm_pi(sk)->sec_level) {
766 		case BT_SECURITY_LOW:
767 			opt = RFCOMM_LM_AUTH;
768 			break;
769 		case BT_SECURITY_MEDIUM:
770 			opt = RFCOMM_LM_AUTH | RFCOMM_LM_ENCRYPT;
771 			break;
772 		case BT_SECURITY_HIGH:
773 			opt = RFCOMM_LM_AUTH | RFCOMM_LM_ENCRYPT |
774 							RFCOMM_LM_SECURE;
775 			break;
776 		default:
777 			opt = 0;
778 			break;
779 		}
780 
781 		if (rfcomm_pi(sk)->role_switch)
782 			opt |= RFCOMM_LM_MASTER;
783 
784 		if (put_user(opt, (u32 __user *) optval))
785 			err = -EFAULT;
786 		break;
787 
788 	case RFCOMM_CONNINFO:
789 		if (sk->sk_state != BT_CONNECTED &&
790 					!rfcomm_pi(sk)->dlc->defer_setup) {
791 			err = -ENOTCONN;
792 			break;
793 		}
794 
795 		l2cap_sk = rfcomm_pi(sk)->dlc->session->sock->sk;
796 
797 		cinfo.hci_handle = l2cap_pi(l2cap_sk)->conn->hcon->handle;
798 		memcpy(cinfo.dev_class, l2cap_pi(l2cap_sk)->conn->hcon->dev_class, 3);
799 
800 		len = min_t(unsigned int, len, sizeof(cinfo));
801 		if (copy_to_user(optval, (char *) &cinfo, len))
802 			err = -EFAULT;
803 
804 		break;
805 
806 	default:
807 		err = -ENOPROTOOPT;
808 		break;
809 	}
810 
811 	release_sock(sk);
812 	return err;
813 }
814 
815 static int rfcomm_sock_getsockopt(struct socket *sock, int level, int optname, char __user *optval, int __user *optlen)
816 {
817 	struct sock *sk = sock->sk;
818 	struct bt_security sec;
819 	int len, err = 0;
820 
821 	BT_DBG("sk %p", sk);
822 
823 	if (level == SOL_RFCOMM)
824 		return rfcomm_sock_getsockopt_old(sock, optname, optval, optlen);
825 
826 	if (level != SOL_BLUETOOTH)
827 		return -ENOPROTOOPT;
828 
829 	if (get_user(len, optlen))
830 		return -EFAULT;
831 
832 	lock_sock(sk);
833 
834 	switch (optname) {
835 	case BT_SECURITY:
836 		if (sk->sk_type != SOCK_STREAM) {
837 			err = -EINVAL;
838 			break;
839 		}
840 
841 		sec.level = rfcomm_pi(sk)->sec_level;
842 
843 		len = min_t(unsigned int, len, sizeof(sec));
844 		if (copy_to_user(optval, (char *) &sec, len))
845 			err = -EFAULT;
846 
847 		break;
848 
849 	case BT_DEFER_SETUP:
850 		if (sk->sk_state != BT_BOUND && sk->sk_state != BT_LISTEN) {
851 			err = -EINVAL;
852 			break;
853 		}
854 
855 		if (put_user(bt_sk(sk)->defer_setup, (u32 __user *) optval))
856 			err = -EFAULT;
857 
858 		break;
859 
860 	default:
861 		err = -ENOPROTOOPT;
862 		break;
863 	}
864 
865 	release_sock(sk);
866 	return err;
867 }
868 
869 static int rfcomm_sock_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
870 {
871 	struct sock *sk __maybe_unused = sock->sk;
872 	int err;
873 
874 	BT_DBG("sk %p cmd %x arg %lx", sk, cmd, arg);
875 
876 	err = bt_sock_ioctl(sock, cmd, arg);
877 
878 	if (err == -ENOIOCTLCMD) {
879 #ifdef CONFIG_BT_RFCOMM_TTY
880 		lock_sock(sk);
881 		err = rfcomm_dev_ioctl(sk, cmd, (void __user *) arg);
882 		release_sock(sk);
883 #else
884 		err = -EOPNOTSUPP;
885 #endif
886 	}
887 
888 	return err;
889 }
890 
891 static int rfcomm_sock_shutdown(struct socket *sock, int how)
892 {
893 	struct sock *sk = sock->sk;
894 	int err = 0;
895 
896 	BT_DBG("sock %p, sk %p", sock, sk);
897 
898 	if (!sk) return 0;
899 
900 	lock_sock(sk);
901 	if (!sk->sk_shutdown) {
902 		sk->sk_shutdown = SHUTDOWN_MASK;
903 		__rfcomm_sock_close(sk);
904 
905 		if (sock_flag(sk, SOCK_LINGER) && sk->sk_lingertime)
906 			err = bt_sock_wait_state(sk, BT_CLOSED, sk->sk_lingertime);
907 	}
908 	release_sock(sk);
909 	return err;
910 }
911 
912 static int rfcomm_sock_release(struct socket *sock)
913 {
914 	struct sock *sk = sock->sk;
915 	int err;
916 
917 	BT_DBG("sock %p, sk %p", sock, sk);
918 
919 	if (!sk)
920 		return 0;
921 
922 	err = rfcomm_sock_shutdown(sock, 2);
923 
924 	sock_orphan(sk);
925 	rfcomm_sock_kill(sk);
926 	return err;
927 }
928 
929 /* ---- RFCOMM core layer callbacks ----
930  *
931  * called under rfcomm_lock()
932  */
933 int rfcomm_connect_ind(struct rfcomm_session *s, u8 channel, struct rfcomm_dlc **d)
934 {
935 	struct sock *sk, *parent;
936 	bdaddr_t src, dst;
937 	int result = 0;
938 
939 	BT_DBG("session %p channel %d", s, channel);
940 
941 	rfcomm_session_getaddr(s, &src, &dst);
942 
943 	/* Check if we have socket listening on channel */
944 	parent = rfcomm_get_sock_by_channel(BT_LISTEN, channel, &src);
945 	if (!parent)
946 		return 0;
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 	rfcomm_sock_init(sk, parent);
959 	bacpy(&bt_sk(sk)->src, &src);
960 	bacpy(&bt_sk(sk)->dst, &dst);
961 	rfcomm_pi(sk)->channel = channel;
962 
963 	sk->sk_state = BT_CONFIG;
964 	bt_accept_enqueue(parent, sk);
965 
966 	/* Accept connection and return socket DLC */
967 	*d = rfcomm_pi(sk)->dlc;
968 	result = 1;
969 
970 done:
971 	bh_unlock_sock(parent);
972 
973 	if (bt_sk(parent)->defer_setup)
974 		parent->sk_state_change(parent);
975 
976 	return result;
977 }
978 
979 static int rfcomm_sock_debugfs_show(struct seq_file *f, void *p)
980 {
981 	struct sock *sk;
982 	struct hlist_node *node;
983 
984 	read_lock_bh(&rfcomm_sk_list.lock);
985 
986 	sk_for_each(sk, node, &rfcomm_sk_list.head) {
987 		seq_printf(f, "%s %s %d %d\n",
988 				batostr(&bt_sk(sk)->src),
989 				batostr(&bt_sk(sk)->dst),
990 				sk->sk_state, rfcomm_pi(sk)->channel);
991 	}
992 
993 	read_unlock_bh(&rfcomm_sk_list.lock);
994 
995 	return 0;
996 }
997 
998 static int rfcomm_sock_debugfs_open(struct inode *inode, struct file *file)
999 {
1000 	return single_open(file, rfcomm_sock_debugfs_show, inode->i_private);
1001 }
1002 
1003 static const struct file_operations rfcomm_sock_debugfs_fops = {
1004 	.open		= rfcomm_sock_debugfs_open,
1005 	.read		= seq_read,
1006 	.llseek		= seq_lseek,
1007 	.release	= single_release,
1008 };
1009 
1010 static struct dentry *rfcomm_sock_debugfs;
1011 
1012 static const struct proto_ops rfcomm_sock_ops = {
1013 	.family		= PF_BLUETOOTH,
1014 	.owner		= THIS_MODULE,
1015 	.release	= rfcomm_sock_release,
1016 	.bind		= rfcomm_sock_bind,
1017 	.connect	= rfcomm_sock_connect,
1018 	.listen		= rfcomm_sock_listen,
1019 	.accept		= rfcomm_sock_accept,
1020 	.getname	= rfcomm_sock_getname,
1021 	.sendmsg	= rfcomm_sock_sendmsg,
1022 	.recvmsg	= rfcomm_sock_recvmsg,
1023 	.shutdown	= rfcomm_sock_shutdown,
1024 	.setsockopt	= rfcomm_sock_setsockopt,
1025 	.getsockopt	= rfcomm_sock_getsockopt,
1026 	.ioctl		= rfcomm_sock_ioctl,
1027 	.poll		= bt_sock_poll,
1028 	.socketpair	= sock_no_socketpair,
1029 	.mmap		= sock_no_mmap
1030 };
1031 
1032 static const struct net_proto_family rfcomm_sock_family_ops = {
1033 	.family		= PF_BLUETOOTH,
1034 	.owner		= THIS_MODULE,
1035 	.create		= rfcomm_sock_create
1036 };
1037 
1038 int __init rfcomm_init_sockets(void)
1039 {
1040 	int err;
1041 
1042 	err = proto_register(&rfcomm_proto, 0);
1043 	if (err < 0)
1044 		return err;
1045 
1046 	err = bt_sock_register(BTPROTO_RFCOMM, &rfcomm_sock_family_ops);
1047 	if (err < 0)
1048 		goto error;
1049 
1050 	if (bt_debugfs) {
1051 		rfcomm_sock_debugfs = debugfs_create_file("rfcomm", 0444,
1052 				bt_debugfs, NULL, &rfcomm_sock_debugfs_fops);
1053 		if (!rfcomm_sock_debugfs)
1054 			BT_ERR("Failed to create RFCOMM debug file");
1055 	}
1056 
1057 	BT_INFO("RFCOMM socket layer initialized");
1058 
1059 	return 0;
1060 
1061 error:
1062 	BT_ERR("RFCOMM socket layer registration failed");
1063 	proto_unregister(&rfcomm_proto);
1064 	return err;
1065 }
1066 
1067 void __exit rfcomm_cleanup_sockets(void)
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