xref: /openbmc/linux/net/bluetooth/rfcomm/sock.c (revision e3b9f1e8)
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 #include <linux/sched/signal.h>
31 
32 #include <net/bluetooth/bluetooth.h>
33 #include <net/bluetooth/hci_core.h>
34 #include <net/bluetooth/l2cap.h>
35 #include <net/bluetooth/rfcomm.h>
36 
37 static const struct proto_ops rfcomm_sock_ops;
38 
39 static struct bt_sock_list rfcomm_sk_list = {
40 	.lock = __RW_LOCK_UNLOCKED(rfcomm_sk_list.lock)
41 };
42 
43 static void rfcomm_sock_close(struct sock *sk);
44 static void rfcomm_sock_kill(struct sock *sk);
45 
46 /* ---- DLC callbacks ----
47  *
48  * called under rfcomm_dlc_lock()
49  */
50 static void rfcomm_sk_data_ready(struct rfcomm_dlc *d, struct sk_buff *skb)
51 {
52 	struct sock *sk = d->owner;
53 	if (!sk)
54 		return;
55 
56 	atomic_add(skb->len, &sk->sk_rmem_alloc);
57 	skb_queue_tail(&sk->sk_receive_queue, skb);
58 	sk->sk_data_ready(sk);
59 
60 	if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf)
61 		rfcomm_dlc_throttle(d);
62 }
63 
64 static void rfcomm_sk_state_change(struct rfcomm_dlc *d, int err)
65 {
66 	struct sock *sk = d->owner, *parent;
67 	unsigned long flags;
68 
69 	if (!sk)
70 		return;
71 
72 	BT_DBG("dlc %p state %ld err %d", d, d->state, err);
73 
74 	local_irq_save(flags);
75 	bh_lock_sock(sk);
76 
77 	if (err)
78 		sk->sk_err = err;
79 
80 	sk->sk_state = d->state;
81 
82 	parent = bt_sk(sk)->parent;
83 	if (parent) {
84 		if (d->state == BT_CLOSED) {
85 			sock_set_flag(sk, SOCK_ZAPPED);
86 			bt_accept_unlink(sk);
87 		}
88 		parent->sk_data_ready(parent);
89 	} else {
90 		if (d->state == BT_CONNECTED)
91 			rfcomm_session_getaddr(d->session,
92 					       &rfcomm_pi(sk)->src, NULL);
93 		sk->sk_state_change(sk);
94 	}
95 
96 	bh_unlock_sock(sk);
97 	local_irq_restore(flags);
98 
99 	if (parent && sock_flag(sk, SOCK_ZAPPED)) {
100 		/* We have to drop DLC lock here, otherwise
101 		 * rfcomm_sock_destruct() will dead lock. */
102 		rfcomm_dlc_unlock(d);
103 		rfcomm_sock_kill(sk);
104 		rfcomm_dlc_lock(d);
105 	}
106 }
107 
108 /* ---- Socket functions ---- */
109 static struct sock *__rfcomm_get_listen_sock_by_addr(u8 channel, bdaddr_t *src)
110 {
111 	struct sock *sk = NULL;
112 
113 	sk_for_each(sk, &rfcomm_sk_list.head) {
114 		if (rfcomm_pi(sk)->channel != channel)
115 			continue;
116 
117 		if (bacmp(&rfcomm_pi(sk)->src, src))
118 			continue;
119 
120 		if (sk->sk_state == BT_BOUND || sk->sk_state == BT_LISTEN)
121 			break;
122 	}
123 
124 	return sk ? sk : NULL;
125 }
126 
127 /* Find socket with channel and source bdaddr.
128  * Returns closest match.
129  */
130 static struct sock *rfcomm_get_sock_by_channel(int state, u8 channel, bdaddr_t *src)
131 {
132 	struct sock *sk = NULL, *sk1 = NULL;
133 
134 	read_lock(&rfcomm_sk_list.lock);
135 
136 	sk_for_each(sk, &rfcomm_sk_list.head) {
137 		if (state && sk->sk_state != state)
138 			continue;
139 
140 		if (rfcomm_pi(sk)->channel == channel) {
141 			/* Exact match. */
142 			if (!bacmp(&rfcomm_pi(sk)->src, src))
143 				break;
144 
145 			/* Closest match */
146 			if (!bacmp(&rfcomm_pi(sk)->src, BDADDR_ANY))
147 				sk1 = sk;
148 		}
149 	}
150 
151 	read_unlock(&rfcomm_sk_list.lock);
152 
153 	return sk ? sk : sk1;
154 }
155 
156 static void rfcomm_sock_destruct(struct sock *sk)
157 {
158 	struct rfcomm_dlc *d = rfcomm_pi(sk)->dlc;
159 
160 	BT_DBG("sk %p dlc %p", sk, d);
161 
162 	skb_queue_purge(&sk->sk_receive_queue);
163 	skb_queue_purge(&sk->sk_write_queue);
164 
165 	rfcomm_dlc_lock(d);
166 	rfcomm_pi(sk)->dlc = NULL;
167 
168 	/* Detach DLC if it's owned by this socket */
169 	if (d->owner == sk)
170 		d->owner = NULL;
171 	rfcomm_dlc_unlock(d);
172 
173 	rfcomm_dlc_put(d);
174 }
175 
176 static void rfcomm_sock_cleanup_listen(struct sock *parent)
177 {
178 	struct sock *sk;
179 
180 	BT_DBG("parent %p", parent);
181 
182 	/* Close not yet accepted dlcs */
183 	while ((sk = bt_accept_dequeue(parent, NULL))) {
184 		rfcomm_sock_close(sk);
185 		rfcomm_sock_kill(sk);
186 	}
187 
188 	parent->sk_state  = BT_CLOSED;
189 	sock_set_flag(parent, SOCK_ZAPPED);
190 }
191 
192 /* Kill socket (only if zapped and orphan)
193  * Must be called on unlocked socket.
194  */
195 static void rfcomm_sock_kill(struct sock *sk)
196 {
197 	if (!sock_flag(sk, SOCK_ZAPPED) || sk->sk_socket)
198 		return;
199 
200 	BT_DBG("sk %p state %d refcnt %d", sk, sk->sk_state, refcount_read(&sk->sk_refcnt));
201 
202 	/* Kill poor orphan */
203 	bt_sock_unlink(&rfcomm_sk_list, sk);
204 	sock_set_flag(sk, SOCK_DEAD);
205 	sock_put(sk);
206 }
207 
208 static void __rfcomm_sock_close(struct sock *sk)
209 {
210 	struct rfcomm_dlc *d = rfcomm_pi(sk)->dlc;
211 
212 	BT_DBG("sk %p state %d socket %p", sk, sk->sk_state, sk->sk_socket);
213 
214 	switch (sk->sk_state) {
215 	case BT_LISTEN:
216 		rfcomm_sock_cleanup_listen(sk);
217 		break;
218 
219 	case BT_CONNECT:
220 	case BT_CONNECT2:
221 	case BT_CONFIG:
222 	case BT_CONNECTED:
223 		rfcomm_dlc_close(d, 0);
224 
225 	default:
226 		sock_set_flag(sk, SOCK_ZAPPED);
227 		break;
228 	}
229 }
230 
231 /* Close socket.
232  * Must be called on unlocked socket.
233  */
234 static void rfcomm_sock_close(struct sock *sk)
235 {
236 	lock_sock(sk);
237 	__rfcomm_sock_close(sk);
238 	release_sock(sk);
239 }
240 
241 static void rfcomm_sock_init(struct sock *sk, struct sock *parent)
242 {
243 	struct rfcomm_pinfo *pi = rfcomm_pi(sk);
244 
245 	BT_DBG("sk %p", sk);
246 
247 	if (parent) {
248 		sk->sk_type = parent->sk_type;
249 		pi->dlc->defer_setup = test_bit(BT_SK_DEFER_SETUP,
250 						&bt_sk(parent)->flags);
251 
252 		pi->sec_level = rfcomm_pi(parent)->sec_level;
253 		pi->role_switch = rfcomm_pi(parent)->role_switch;
254 
255 		security_sk_clone(parent, sk);
256 	} else {
257 		pi->dlc->defer_setup = 0;
258 
259 		pi->sec_level = BT_SECURITY_LOW;
260 		pi->role_switch = 0;
261 	}
262 
263 	pi->dlc->sec_level = pi->sec_level;
264 	pi->dlc->role_switch = pi->role_switch;
265 }
266 
267 static struct proto rfcomm_proto = {
268 	.name		= "RFCOMM",
269 	.owner		= THIS_MODULE,
270 	.obj_size	= sizeof(struct rfcomm_pinfo)
271 };
272 
273 static struct sock *rfcomm_sock_alloc(struct net *net, struct socket *sock, int proto, gfp_t prio, int kern)
274 {
275 	struct rfcomm_dlc *d;
276 	struct sock *sk;
277 
278 	sk = sk_alloc(net, PF_BLUETOOTH, prio, &rfcomm_proto, kern);
279 	if (!sk)
280 		return NULL;
281 
282 	sock_init_data(sock, sk);
283 	INIT_LIST_HEAD(&bt_sk(sk)->accept_q);
284 
285 	d = rfcomm_dlc_alloc(prio);
286 	if (!d) {
287 		sk_free(sk);
288 		return NULL;
289 	}
290 
291 	d->data_ready   = rfcomm_sk_data_ready;
292 	d->state_change = rfcomm_sk_state_change;
293 
294 	rfcomm_pi(sk)->dlc = d;
295 	d->owner = sk;
296 
297 	sk->sk_destruct = rfcomm_sock_destruct;
298 	sk->sk_sndtimeo = RFCOMM_CONN_TIMEOUT;
299 
300 	sk->sk_sndbuf = RFCOMM_MAX_CREDITS * RFCOMM_DEFAULT_MTU * 10;
301 	sk->sk_rcvbuf = RFCOMM_MAX_CREDITS * RFCOMM_DEFAULT_MTU * 10;
302 
303 	sock_reset_flag(sk, SOCK_ZAPPED);
304 
305 	sk->sk_protocol = proto;
306 	sk->sk_state    = BT_OPEN;
307 
308 	bt_sock_link(&rfcomm_sk_list, sk);
309 
310 	BT_DBG("sk %p", sk);
311 	return sk;
312 }
313 
314 static int rfcomm_sock_create(struct net *net, struct socket *sock,
315 			      int protocol, int kern)
316 {
317 	struct sock *sk;
318 
319 	BT_DBG("sock %p", sock);
320 
321 	sock->state = SS_UNCONNECTED;
322 
323 	if (sock->type != SOCK_STREAM && sock->type != SOCK_RAW)
324 		return -ESOCKTNOSUPPORT;
325 
326 	sock->ops = &rfcomm_sock_ops;
327 
328 	sk = rfcomm_sock_alloc(net, sock, protocol, GFP_ATOMIC, kern);
329 	if (!sk)
330 		return -ENOMEM;
331 
332 	rfcomm_sock_init(sk, NULL);
333 	return 0;
334 }
335 
336 static int rfcomm_sock_bind(struct socket *sock, struct sockaddr *addr, int addr_len)
337 {
338 	struct sockaddr_rc sa;
339 	struct sock *sk = sock->sk;
340 	int len, err = 0;
341 
342 	if (!addr || addr_len < offsetofend(struct sockaddr, sa_family) ||
343 	    addr->sa_family != AF_BLUETOOTH)
344 		return -EINVAL;
345 
346 	memset(&sa, 0, sizeof(sa));
347 	len = min_t(unsigned int, sizeof(sa), addr_len);
348 	memcpy(&sa, addr, len);
349 
350 	BT_DBG("sk %p %pMR", sk, &sa.rc_bdaddr);
351 
352 	lock_sock(sk);
353 
354 	if (sk->sk_state != BT_OPEN) {
355 		err = -EBADFD;
356 		goto done;
357 	}
358 
359 	if (sk->sk_type != SOCK_STREAM) {
360 		err = -EINVAL;
361 		goto done;
362 	}
363 
364 	write_lock(&rfcomm_sk_list.lock);
365 
366 	if (sa.rc_channel &&
367 	    __rfcomm_get_listen_sock_by_addr(sa.rc_channel, &sa.rc_bdaddr)) {
368 		err = -EADDRINUSE;
369 	} else {
370 		/* Save source address */
371 		bacpy(&rfcomm_pi(sk)->src, &sa.rc_bdaddr);
372 		rfcomm_pi(sk)->channel = sa.rc_channel;
373 		sk->sk_state = BT_BOUND;
374 	}
375 
376 	write_unlock(&rfcomm_sk_list.lock);
377 
378 done:
379 	release_sock(sk);
380 	return err;
381 }
382 
383 static int rfcomm_sock_connect(struct socket *sock, struct sockaddr *addr, int alen, int flags)
384 {
385 	struct sockaddr_rc *sa = (struct sockaddr_rc *) addr;
386 	struct sock *sk = sock->sk;
387 	struct rfcomm_dlc *d = rfcomm_pi(sk)->dlc;
388 	int err = 0;
389 
390 	BT_DBG("sk %p", sk);
391 
392 	if (alen < sizeof(struct sockaddr_rc) ||
393 	    addr->sa_family != AF_BLUETOOTH)
394 		return -EINVAL;
395 
396 	lock_sock(sk);
397 
398 	if (sk->sk_state != BT_OPEN && sk->sk_state != BT_BOUND) {
399 		err = -EBADFD;
400 		goto done;
401 	}
402 
403 	if (sk->sk_type != SOCK_STREAM) {
404 		err = -EINVAL;
405 		goto done;
406 	}
407 
408 	sk->sk_state = BT_CONNECT;
409 	bacpy(&rfcomm_pi(sk)->dst, &sa->rc_bdaddr);
410 	rfcomm_pi(sk)->channel = sa->rc_channel;
411 
412 	d->sec_level = rfcomm_pi(sk)->sec_level;
413 	d->role_switch = rfcomm_pi(sk)->role_switch;
414 
415 	err = rfcomm_dlc_open(d, &rfcomm_pi(sk)->src, &sa->rc_bdaddr,
416 			      sa->rc_channel);
417 	if (!err)
418 		err = bt_sock_wait_state(sk, BT_CONNECTED,
419 				sock_sndtimeo(sk, flags & O_NONBLOCK));
420 
421 done:
422 	release_sock(sk);
423 	return err;
424 }
425 
426 static int rfcomm_sock_listen(struct socket *sock, int backlog)
427 {
428 	struct sock *sk = sock->sk;
429 	int err = 0;
430 
431 	BT_DBG("sk %p backlog %d", sk, backlog);
432 
433 	lock_sock(sk);
434 
435 	if (sk->sk_state != BT_BOUND) {
436 		err = -EBADFD;
437 		goto done;
438 	}
439 
440 	if (sk->sk_type != SOCK_STREAM) {
441 		err = -EINVAL;
442 		goto done;
443 	}
444 
445 	if (!rfcomm_pi(sk)->channel) {
446 		bdaddr_t *src = &rfcomm_pi(sk)->src;
447 		u8 channel;
448 
449 		err = -EINVAL;
450 
451 		write_lock(&rfcomm_sk_list.lock);
452 
453 		for (channel = 1; channel < 31; channel++)
454 			if (!__rfcomm_get_listen_sock_by_addr(channel, src)) {
455 				rfcomm_pi(sk)->channel = channel;
456 				err = 0;
457 				break;
458 			}
459 
460 		write_unlock(&rfcomm_sk_list.lock);
461 
462 		if (err < 0)
463 			goto done;
464 	}
465 
466 	sk->sk_max_ack_backlog = backlog;
467 	sk->sk_ack_backlog = 0;
468 	sk->sk_state = BT_LISTEN;
469 
470 done:
471 	release_sock(sk);
472 	return err;
473 }
474 
475 static int rfcomm_sock_accept(struct socket *sock, struct socket *newsock, int flags,
476 			      bool kern)
477 {
478 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
479 	struct sock *sk = sock->sk, *nsk;
480 	long timeo;
481 	int err = 0;
482 
483 	lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
484 
485 	if (sk->sk_type != SOCK_STREAM) {
486 		err = -EINVAL;
487 		goto done;
488 	}
489 
490 	timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
491 
492 	BT_DBG("sk %p timeo %ld", sk, timeo);
493 
494 	/* Wait for an incoming connection. (wake-one). */
495 	add_wait_queue_exclusive(sk_sleep(sk), &wait);
496 	while (1) {
497 		if (sk->sk_state != BT_LISTEN) {
498 			err = -EBADFD;
499 			break;
500 		}
501 
502 		nsk = bt_accept_dequeue(sk, newsock);
503 		if (nsk)
504 			break;
505 
506 		if (!timeo) {
507 			err = -EAGAIN;
508 			break;
509 		}
510 
511 		if (signal_pending(current)) {
512 			err = sock_intr_errno(timeo);
513 			break;
514 		}
515 
516 		release_sock(sk);
517 
518 		timeo = wait_woken(&wait, TASK_INTERRUPTIBLE, timeo);
519 
520 		lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
521 	}
522 	remove_wait_queue(sk_sleep(sk), &wait);
523 
524 	if (err)
525 		goto done;
526 
527 	newsock->state = SS_CONNECTED;
528 
529 	BT_DBG("new socket %p", nsk);
530 
531 done:
532 	release_sock(sk);
533 	return err;
534 }
535 
536 static int rfcomm_sock_getname(struct socket *sock, struct sockaddr *addr, int *len, int peer)
537 {
538 	struct sockaddr_rc *sa = (struct sockaddr_rc *) addr;
539 	struct sock *sk = sock->sk;
540 
541 	BT_DBG("sock %p, sk %p", sock, sk);
542 
543 	if (peer && sk->sk_state != BT_CONNECTED &&
544 	    sk->sk_state != BT_CONNECT && sk->sk_state != BT_CONNECT2)
545 		return -ENOTCONN;
546 
547 	memset(sa, 0, sizeof(*sa));
548 	sa->rc_family  = AF_BLUETOOTH;
549 	sa->rc_channel = rfcomm_pi(sk)->channel;
550 	if (peer)
551 		bacpy(&sa->rc_bdaddr, &rfcomm_pi(sk)->dst);
552 	else
553 		bacpy(&sa->rc_bdaddr, &rfcomm_pi(sk)->src);
554 
555 	*len = sizeof(struct sockaddr_rc);
556 	return 0;
557 }
558 
559 static int rfcomm_sock_sendmsg(struct socket *sock, struct msghdr *msg,
560 			       size_t len)
561 {
562 	struct sock *sk = sock->sk;
563 	struct rfcomm_dlc *d = rfcomm_pi(sk)->dlc;
564 	struct sk_buff *skb;
565 	int sent;
566 
567 	if (test_bit(RFCOMM_DEFER_SETUP, &d->flags))
568 		return -ENOTCONN;
569 
570 	if (msg->msg_flags & MSG_OOB)
571 		return -EOPNOTSUPP;
572 
573 	if (sk->sk_shutdown & SEND_SHUTDOWN)
574 		return -EPIPE;
575 
576 	BT_DBG("sock %p, sk %p", sock, sk);
577 
578 	lock_sock(sk);
579 
580 	sent = bt_sock_wait_ready(sk, msg->msg_flags);
581 	if (sent)
582 		goto done;
583 
584 	while (len) {
585 		size_t size = min_t(size_t, len, d->mtu);
586 		int err;
587 
588 		skb = sock_alloc_send_skb(sk, size + RFCOMM_SKB_RESERVE,
589 				msg->msg_flags & MSG_DONTWAIT, &err);
590 		if (!skb) {
591 			if (sent == 0)
592 				sent = err;
593 			break;
594 		}
595 		skb_reserve(skb, RFCOMM_SKB_HEAD_RESERVE);
596 
597 		err = memcpy_from_msg(skb_put(skb, size), msg, size);
598 		if (err) {
599 			kfree_skb(skb);
600 			if (sent == 0)
601 				sent = err;
602 			break;
603 		}
604 
605 		skb->priority = sk->sk_priority;
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 done:
620 	release_sock(sk);
621 
622 	return sent;
623 }
624 
625 static int rfcomm_sock_recvmsg(struct socket *sock, struct msghdr *msg,
626 			       size_t size, int flags)
627 {
628 	struct sock *sk = sock->sk;
629 	struct rfcomm_dlc *d = rfcomm_pi(sk)->dlc;
630 	int len;
631 
632 	if (test_and_clear_bit(RFCOMM_DEFER_SETUP, &d->flags)) {
633 		rfcomm_dlc_accept(d);
634 		return 0;
635 	}
636 
637 	len = bt_sock_stream_recvmsg(sock, msg, size, flags);
638 
639 	lock_sock(sk);
640 	if (!(flags & MSG_PEEK) && len > 0)
641 		atomic_sub(len, &sk->sk_rmem_alloc);
642 
643 	if (atomic_read(&sk->sk_rmem_alloc) <= (sk->sk_rcvbuf >> 2))
644 		rfcomm_dlc_unthrottle(rfcomm_pi(sk)->dlc);
645 	release_sock(sk);
646 
647 	return len;
648 }
649 
650 static int rfcomm_sock_setsockopt_old(struct socket *sock, int optname, char __user *optval, unsigned int optlen)
651 {
652 	struct sock *sk = sock->sk;
653 	int err = 0;
654 	u32 opt;
655 
656 	BT_DBG("sk %p", sk);
657 
658 	lock_sock(sk);
659 
660 	switch (optname) {
661 	case RFCOMM_LM:
662 		if (get_user(opt, (u32 __user *) optval)) {
663 			err = -EFAULT;
664 			break;
665 		}
666 
667 		if (opt & RFCOMM_LM_FIPS) {
668 			err = -EINVAL;
669 			break;
670 		}
671 
672 		if (opt & RFCOMM_LM_AUTH)
673 			rfcomm_pi(sk)->sec_level = BT_SECURITY_LOW;
674 		if (opt & RFCOMM_LM_ENCRYPT)
675 			rfcomm_pi(sk)->sec_level = BT_SECURITY_MEDIUM;
676 		if (opt & RFCOMM_LM_SECURE)
677 			rfcomm_pi(sk)->sec_level = BT_SECURITY_HIGH;
678 
679 		rfcomm_pi(sk)->role_switch = (opt & RFCOMM_LM_MASTER);
680 		break;
681 
682 	default:
683 		err = -ENOPROTOOPT;
684 		break;
685 	}
686 
687 	release_sock(sk);
688 	return err;
689 }
690 
691 static int rfcomm_sock_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen)
692 {
693 	struct sock *sk = sock->sk;
694 	struct bt_security sec;
695 	int err = 0;
696 	size_t len;
697 	u32 opt;
698 
699 	BT_DBG("sk %p", sk);
700 
701 	if (level == SOL_RFCOMM)
702 		return rfcomm_sock_setsockopt_old(sock, optname, optval, optlen);
703 
704 	if (level != SOL_BLUETOOTH)
705 		return -ENOPROTOOPT;
706 
707 	lock_sock(sk);
708 
709 	switch (optname) {
710 	case BT_SECURITY:
711 		if (sk->sk_type != SOCK_STREAM) {
712 			err = -EINVAL;
713 			break;
714 		}
715 
716 		sec.level = BT_SECURITY_LOW;
717 
718 		len = min_t(unsigned int, sizeof(sec), optlen);
719 		if (copy_from_user((char *) &sec, optval, len)) {
720 			err = -EFAULT;
721 			break;
722 		}
723 
724 		if (sec.level > BT_SECURITY_HIGH) {
725 			err = -EINVAL;
726 			break;
727 		}
728 
729 		rfcomm_pi(sk)->sec_level = sec.level;
730 		break;
731 
732 	case BT_DEFER_SETUP:
733 		if (sk->sk_state != BT_BOUND && sk->sk_state != BT_LISTEN) {
734 			err = -EINVAL;
735 			break;
736 		}
737 
738 		if (get_user(opt, (u32 __user *) optval)) {
739 			err = -EFAULT;
740 			break;
741 		}
742 
743 		if (opt)
744 			set_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags);
745 		else
746 			clear_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags);
747 
748 		break;
749 
750 	default:
751 		err = -ENOPROTOOPT;
752 		break;
753 	}
754 
755 	release_sock(sk);
756 	return err;
757 }
758 
759 static int rfcomm_sock_getsockopt_old(struct socket *sock, int optname, char __user *optval, int __user *optlen)
760 {
761 	struct sock *sk = sock->sk;
762 	struct sock *l2cap_sk;
763 	struct l2cap_conn *conn;
764 	struct rfcomm_conninfo cinfo;
765 	int len, err = 0;
766 	u32 opt;
767 
768 	BT_DBG("sk %p", sk);
769 
770 	if (get_user(len, optlen))
771 		return -EFAULT;
772 
773 	lock_sock(sk);
774 
775 	switch (optname) {
776 	case RFCOMM_LM:
777 		switch (rfcomm_pi(sk)->sec_level) {
778 		case BT_SECURITY_LOW:
779 			opt = RFCOMM_LM_AUTH;
780 			break;
781 		case BT_SECURITY_MEDIUM:
782 			opt = RFCOMM_LM_AUTH | RFCOMM_LM_ENCRYPT;
783 			break;
784 		case BT_SECURITY_HIGH:
785 			opt = RFCOMM_LM_AUTH | RFCOMM_LM_ENCRYPT |
786 			      RFCOMM_LM_SECURE;
787 			break;
788 		case BT_SECURITY_FIPS:
789 			opt = RFCOMM_LM_AUTH | RFCOMM_LM_ENCRYPT |
790 			      RFCOMM_LM_SECURE | RFCOMM_LM_FIPS;
791 			break;
792 		default:
793 			opt = 0;
794 			break;
795 		}
796 
797 		if (rfcomm_pi(sk)->role_switch)
798 			opt |= RFCOMM_LM_MASTER;
799 
800 		if (put_user(opt, (u32 __user *) optval))
801 			err = -EFAULT;
802 
803 		break;
804 
805 	case RFCOMM_CONNINFO:
806 		if (sk->sk_state != BT_CONNECTED &&
807 					!rfcomm_pi(sk)->dlc->defer_setup) {
808 			err = -ENOTCONN;
809 			break;
810 		}
811 
812 		l2cap_sk = rfcomm_pi(sk)->dlc->session->sock->sk;
813 		conn = l2cap_pi(l2cap_sk)->chan->conn;
814 
815 		memset(&cinfo, 0, sizeof(cinfo));
816 		cinfo.hci_handle = conn->hcon->handle;
817 		memcpy(cinfo.dev_class, conn->hcon->dev_class, 3);
818 
819 		len = min_t(unsigned int, len, sizeof(cinfo));
820 		if (copy_to_user(optval, (char *) &cinfo, len))
821 			err = -EFAULT;
822 
823 		break;
824 
825 	default:
826 		err = -ENOPROTOOPT;
827 		break;
828 	}
829 
830 	release_sock(sk);
831 	return err;
832 }
833 
834 static int rfcomm_sock_getsockopt(struct socket *sock, int level, int optname, char __user *optval, int __user *optlen)
835 {
836 	struct sock *sk = sock->sk;
837 	struct bt_security sec;
838 	int len, err = 0;
839 
840 	BT_DBG("sk %p", sk);
841 
842 	if (level == SOL_RFCOMM)
843 		return rfcomm_sock_getsockopt_old(sock, optname, optval, optlen);
844 
845 	if (level != SOL_BLUETOOTH)
846 		return -ENOPROTOOPT;
847 
848 	if (get_user(len, optlen))
849 		return -EFAULT;
850 
851 	lock_sock(sk);
852 
853 	switch (optname) {
854 	case BT_SECURITY:
855 		if (sk->sk_type != SOCK_STREAM) {
856 			err = -EINVAL;
857 			break;
858 		}
859 
860 		sec.level = rfcomm_pi(sk)->sec_level;
861 		sec.key_size = 0;
862 
863 		len = min_t(unsigned int, len, sizeof(sec));
864 		if (copy_to_user(optval, (char *) &sec, len))
865 			err = -EFAULT;
866 
867 		break;
868 
869 	case BT_DEFER_SETUP:
870 		if (sk->sk_state != BT_BOUND && sk->sk_state != BT_LISTEN) {
871 			err = -EINVAL;
872 			break;
873 		}
874 
875 		if (put_user(test_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags),
876 			     (u32 __user *) optval))
877 			err = -EFAULT;
878 
879 		break;
880 
881 	default:
882 		err = -ENOPROTOOPT;
883 		break;
884 	}
885 
886 	release_sock(sk);
887 	return err;
888 }
889 
890 static int rfcomm_sock_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
891 {
892 	struct sock *sk __maybe_unused = sock->sk;
893 	int err;
894 
895 	BT_DBG("sk %p cmd %x arg %lx", sk, cmd, arg);
896 
897 	err = bt_sock_ioctl(sock, cmd, arg);
898 
899 	if (err == -ENOIOCTLCMD) {
900 #ifdef CONFIG_BT_RFCOMM_TTY
901 		lock_sock(sk);
902 		err = rfcomm_dev_ioctl(sk, cmd, (void __user *) arg);
903 		release_sock(sk);
904 #else
905 		err = -EOPNOTSUPP;
906 #endif
907 	}
908 
909 	return err;
910 }
911 
912 static int rfcomm_sock_shutdown(struct socket *sock, int how)
913 {
914 	struct sock *sk = sock->sk;
915 	int err = 0;
916 
917 	BT_DBG("sock %p, sk %p", sock, sk);
918 
919 	if (!sk)
920 		return 0;
921 
922 	lock_sock(sk);
923 	if (!sk->sk_shutdown) {
924 		sk->sk_shutdown = SHUTDOWN_MASK;
925 		__rfcomm_sock_close(sk);
926 
927 		if (sock_flag(sk, SOCK_LINGER) && sk->sk_lingertime &&
928 		    !(current->flags & PF_EXITING))
929 			err = bt_sock_wait_state(sk, BT_CLOSED, sk->sk_lingertime);
930 	}
931 	release_sock(sk);
932 	return err;
933 }
934 
935 static int rfcomm_sock_release(struct socket *sock)
936 {
937 	struct sock *sk = sock->sk;
938 	int err;
939 
940 	BT_DBG("sock %p, sk %p", sock, sk);
941 
942 	if (!sk)
943 		return 0;
944 
945 	err = rfcomm_sock_shutdown(sock, 2);
946 
947 	sock_orphan(sk);
948 	rfcomm_sock_kill(sk);
949 	return err;
950 }
951 
952 /* ---- RFCOMM core layer callbacks ----
953  *
954  * called under rfcomm_lock()
955  */
956 int rfcomm_connect_ind(struct rfcomm_session *s, u8 channel, struct rfcomm_dlc **d)
957 {
958 	struct sock *sk, *parent;
959 	bdaddr_t src, dst;
960 	int result = 0;
961 
962 	BT_DBG("session %p channel %d", s, channel);
963 
964 	rfcomm_session_getaddr(s, &src, &dst);
965 
966 	/* Check if we have socket listening on channel */
967 	parent = rfcomm_get_sock_by_channel(BT_LISTEN, channel, &src);
968 	if (!parent)
969 		return 0;
970 
971 	bh_lock_sock(parent);
972 
973 	/* Check for backlog size */
974 	if (sk_acceptq_is_full(parent)) {
975 		BT_DBG("backlog full %d", parent->sk_ack_backlog);
976 		goto done;
977 	}
978 
979 	sk = rfcomm_sock_alloc(sock_net(parent), NULL, BTPROTO_RFCOMM, GFP_ATOMIC, 0);
980 	if (!sk)
981 		goto done;
982 
983 	bt_sock_reclassify_lock(sk, BTPROTO_RFCOMM);
984 
985 	rfcomm_sock_init(sk, parent);
986 	bacpy(&rfcomm_pi(sk)->src, &src);
987 	bacpy(&rfcomm_pi(sk)->dst, &dst);
988 	rfcomm_pi(sk)->channel = channel;
989 
990 	sk->sk_state = BT_CONFIG;
991 	bt_accept_enqueue(parent, sk);
992 
993 	/* Accept connection and return socket DLC */
994 	*d = rfcomm_pi(sk)->dlc;
995 	result = 1;
996 
997 done:
998 	bh_unlock_sock(parent);
999 
1000 	if (test_bit(BT_SK_DEFER_SETUP, &bt_sk(parent)->flags))
1001 		parent->sk_state_change(parent);
1002 
1003 	return result;
1004 }
1005 
1006 static int rfcomm_sock_debugfs_show(struct seq_file *f, void *p)
1007 {
1008 	struct sock *sk;
1009 
1010 	read_lock(&rfcomm_sk_list.lock);
1011 
1012 	sk_for_each(sk, &rfcomm_sk_list.head) {
1013 		seq_printf(f, "%pMR %pMR %d %d\n",
1014 			   &rfcomm_pi(sk)->src, &rfcomm_pi(sk)->dst,
1015 			   sk->sk_state, rfcomm_pi(sk)->channel);
1016 	}
1017 
1018 	read_unlock(&rfcomm_sk_list.lock);
1019 
1020 	return 0;
1021 }
1022 
1023 static int rfcomm_sock_debugfs_open(struct inode *inode, struct file *file)
1024 {
1025 	return single_open(file, rfcomm_sock_debugfs_show, inode->i_private);
1026 }
1027 
1028 static const struct file_operations rfcomm_sock_debugfs_fops = {
1029 	.open		= rfcomm_sock_debugfs_open,
1030 	.read		= seq_read,
1031 	.llseek		= seq_lseek,
1032 	.release	= single_release,
1033 };
1034 
1035 static struct dentry *rfcomm_sock_debugfs;
1036 
1037 static const struct proto_ops rfcomm_sock_ops = {
1038 	.family		= PF_BLUETOOTH,
1039 	.owner		= THIS_MODULE,
1040 	.release	= rfcomm_sock_release,
1041 	.bind		= rfcomm_sock_bind,
1042 	.connect	= rfcomm_sock_connect,
1043 	.listen		= rfcomm_sock_listen,
1044 	.accept		= rfcomm_sock_accept,
1045 	.getname	= rfcomm_sock_getname,
1046 	.sendmsg	= rfcomm_sock_sendmsg,
1047 	.recvmsg	= rfcomm_sock_recvmsg,
1048 	.shutdown	= rfcomm_sock_shutdown,
1049 	.setsockopt	= rfcomm_sock_setsockopt,
1050 	.getsockopt	= rfcomm_sock_getsockopt,
1051 	.ioctl		= rfcomm_sock_ioctl,
1052 	.poll		= bt_sock_poll,
1053 	.socketpair	= sock_no_socketpair,
1054 	.mmap		= sock_no_mmap
1055 };
1056 
1057 static const struct net_proto_family rfcomm_sock_family_ops = {
1058 	.family		= PF_BLUETOOTH,
1059 	.owner		= THIS_MODULE,
1060 	.create		= rfcomm_sock_create
1061 };
1062 
1063 int __init rfcomm_init_sockets(void)
1064 {
1065 	int err;
1066 
1067 	BUILD_BUG_ON(sizeof(struct sockaddr_rc) > sizeof(struct sockaddr));
1068 
1069 	err = proto_register(&rfcomm_proto, 0);
1070 	if (err < 0)
1071 		return err;
1072 
1073 	err = bt_sock_register(BTPROTO_RFCOMM, &rfcomm_sock_family_ops);
1074 	if (err < 0) {
1075 		BT_ERR("RFCOMM socket layer registration failed");
1076 		goto error;
1077 	}
1078 
1079 	err = bt_procfs_init(&init_net, "rfcomm", &rfcomm_sk_list, NULL);
1080 	if (err < 0) {
1081 		BT_ERR("Failed to create RFCOMM proc file");
1082 		bt_sock_unregister(BTPROTO_RFCOMM);
1083 		goto error;
1084 	}
1085 
1086 	BT_INFO("RFCOMM socket layer initialized");
1087 
1088 	if (IS_ERR_OR_NULL(bt_debugfs))
1089 		return 0;
1090 
1091 	rfcomm_sock_debugfs = debugfs_create_file("rfcomm", 0444,
1092 						  bt_debugfs, NULL,
1093 						  &rfcomm_sock_debugfs_fops);
1094 
1095 	return 0;
1096 
1097 error:
1098 	proto_unregister(&rfcomm_proto);
1099 	return err;
1100 }
1101 
1102 void __exit rfcomm_cleanup_sockets(void)
1103 {
1104 	bt_procfs_cleanup(&init_net, "rfcomm");
1105 
1106 	debugfs_remove(rfcomm_sock_debugfs);
1107 
1108 	bt_sock_unregister(BTPROTO_RFCOMM);
1109 
1110 	proto_unregister(&rfcomm_proto);
1111 }
1112