xref: /openbmc/linux/net/bluetooth/l2cap_sock.c (revision 39d5a3ee355fa903ef4609402c79f570eb9fc4d2)
1 /*
2    BlueZ - Bluetooth protocol stack for Linux
3    Copyright (C) 2000-2001 Qualcomm Incorporated
4    Copyright (C) 2009-2010 Gustavo F. Padovan <gustavo@padovan.org>
5    Copyright (C) 2010 Google Inc.
6 
7    Written 2000,2001 by Maxim Krasnyansky <maxk@qualcomm.com>
8 
9    This program is free software; you can redistribute it and/or modify
10    it under the terms of the GNU General Public License version 2 as
11    published by the Free Software Foundation;
12 
13    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
14    OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
15    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
16    IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY
17    CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES
18    WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
19    ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
20    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
21 
22    ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS,
23    COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS
24    SOFTWARE IS DISCLAIMED.
25 */
26 
27 /* Bluetooth L2CAP sockets. */
28 
29 #include <net/bluetooth/bluetooth.h>
30 #include <net/bluetooth/hci_core.h>
31 #include <net/bluetooth/l2cap.h>
32 
33 /* ---- L2CAP timers ---- */
34 static void l2cap_sock_timeout(unsigned long arg)
35 {
36 	struct sock *sk = (struct sock *) arg;
37 	int reason;
38 
39 	BT_DBG("sock %p state %d", sk, sk->sk_state);
40 
41 	bh_lock_sock(sk);
42 
43 	if (sock_owned_by_user(sk)) {
44 		/* sk is owned by user. Try again later */
45 		l2cap_sock_set_timer(sk, HZ / 5);
46 		bh_unlock_sock(sk);
47 		sock_put(sk);
48 		return;
49 	}
50 
51 	if (sk->sk_state == BT_CONNECTED || sk->sk_state == BT_CONFIG)
52 		reason = ECONNREFUSED;
53 	else if (sk->sk_state == BT_CONNECT &&
54 				l2cap_pi(sk)->sec_level != BT_SECURITY_SDP)
55 		reason = ECONNREFUSED;
56 	else
57 		reason = ETIMEDOUT;
58 
59 	__l2cap_sock_close(sk, reason);
60 
61 	bh_unlock_sock(sk);
62 
63 	l2cap_sock_kill(sk);
64 	sock_put(sk);
65 }
66 
67 void l2cap_sock_set_timer(struct sock *sk, long timeout)
68 {
69 	BT_DBG("sk %p state %d timeout %ld", sk, sk->sk_state, timeout);
70 	sk_reset_timer(sk, &sk->sk_timer, jiffies + timeout);
71 }
72 
73 void l2cap_sock_clear_timer(struct sock *sk)
74 {
75 	BT_DBG("sock %p state %d", sk, sk->sk_state);
76 	sk_stop_timer(sk, &sk->sk_timer);
77 }
78 
79 static struct sock *__l2cap_get_sock_by_addr(__le16 psm, bdaddr_t *src)
80 {
81 	struct sock *sk;
82 	struct hlist_node *node;
83 	sk_for_each(sk, node, &l2cap_sk_list.head)
84 		if (l2cap_pi(sk)->sport == psm && !bacmp(&bt_sk(sk)->src, src))
85 			goto found;
86 	sk = NULL;
87 found:
88 	return sk;
89 }
90 
91 static int l2cap_sock_bind(struct socket *sock, struct sockaddr *addr, int alen)
92 {
93 	struct sock *sk = sock->sk;
94 	struct sockaddr_l2 la;
95 	int len, err = 0;
96 
97 	BT_DBG("sk %p", sk);
98 
99 	if (!addr || addr->sa_family != AF_BLUETOOTH)
100 		return -EINVAL;
101 
102 	memset(&la, 0, sizeof(la));
103 	len = min_t(unsigned int, sizeof(la), alen);
104 	memcpy(&la, addr, len);
105 
106 	if (la.l2_cid && la.l2_psm)
107 		return -EINVAL;
108 
109 	lock_sock(sk);
110 
111 	if (sk->sk_state != BT_OPEN) {
112 		err = -EBADFD;
113 		goto done;
114 	}
115 
116 	if (la.l2_psm) {
117 		__u16 psm = __le16_to_cpu(la.l2_psm);
118 
119 		/* PSM must be odd and lsb of upper byte must be 0 */
120 		if ((psm & 0x0101) != 0x0001) {
121 			err = -EINVAL;
122 			goto done;
123 		}
124 
125 		/* Restrict usage of well-known PSMs */
126 		if (psm < 0x1001 && !capable(CAP_NET_BIND_SERVICE)) {
127 			err = -EACCES;
128 			goto done;
129 		}
130 	}
131 
132 	write_lock_bh(&l2cap_sk_list.lock);
133 
134 	if (la.l2_psm && __l2cap_get_sock_by_addr(la.l2_psm, &la.l2_bdaddr)) {
135 		err = -EADDRINUSE;
136 	} else {
137 		/* Save source address */
138 		bacpy(&bt_sk(sk)->src, &la.l2_bdaddr);
139 		l2cap_pi(sk)->psm   = la.l2_psm;
140 		l2cap_pi(sk)->sport = la.l2_psm;
141 		sk->sk_state = BT_BOUND;
142 
143 		if (__le16_to_cpu(la.l2_psm) == 0x0001 ||
144 					__le16_to_cpu(la.l2_psm) == 0x0003)
145 			l2cap_pi(sk)->sec_level = BT_SECURITY_SDP;
146 	}
147 
148 	if (la.l2_cid)
149 		l2cap_pi(sk)->scid = la.l2_cid;
150 
151 	write_unlock_bh(&l2cap_sk_list.lock);
152 
153 done:
154 	release_sock(sk);
155 	return err;
156 }
157 
158 static int l2cap_sock_connect(struct socket *sock, struct sockaddr *addr, int alen, int flags)
159 {
160 	struct sock *sk = sock->sk;
161 	struct sockaddr_l2 la;
162 	int len, err = 0;
163 
164 	BT_DBG("sk %p", sk);
165 
166 	if (!addr || alen < sizeof(addr->sa_family) ||
167 	    addr->sa_family != AF_BLUETOOTH)
168 		return -EINVAL;
169 
170 	memset(&la, 0, sizeof(la));
171 	len = min_t(unsigned int, sizeof(la), alen);
172 	memcpy(&la, addr, len);
173 
174 	if (la.l2_cid && la.l2_psm)
175 		return -EINVAL;
176 
177 	lock_sock(sk);
178 
179 	if ((sk->sk_type == SOCK_SEQPACKET || sk->sk_type == SOCK_STREAM)
180 			&& !(la.l2_psm || la.l2_cid)) {
181 		err = -EINVAL;
182 		goto done;
183 	}
184 
185 	switch (l2cap_pi(sk)->mode) {
186 	case L2CAP_MODE_BASIC:
187 		break;
188 	case L2CAP_MODE_ERTM:
189 	case L2CAP_MODE_STREAMING:
190 		if (!disable_ertm)
191 			break;
192 		/* fall through */
193 	default:
194 		err = -ENOTSUPP;
195 		goto done;
196 	}
197 
198 	switch (sk->sk_state) {
199 	case BT_CONNECT:
200 	case BT_CONNECT2:
201 	case BT_CONFIG:
202 		/* Already connecting */
203 		goto wait;
204 
205 	case BT_CONNECTED:
206 		/* Already connected */
207 		err = -EISCONN;
208 		goto done;
209 
210 	case BT_OPEN:
211 	case BT_BOUND:
212 		/* Can connect */
213 		break;
214 
215 	default:
216 		err = -EBADFD;
217 		goto done;
218 	}
219 
220 	/* PSM must be odd and lsb of upper byte must be 0 */
221 	if ((__le16_to_cpu(la.l2_psm) & 0x0101) != 0x0001 &&
222 				sk->sk_type != SOCK_RAW && !la.l2_cid) {
223 		err = -EINVAL;
224 		goto done;
225 	}
226 
227 	/* Set destination address and psm */
228 	bacpy(&bt_sk(sk)->dst, &la.l2_bdaddr);
229 	l2cap_pi(sk)->psm = la.l2_psm;
230 	l2cap_pi(sk)->dcid = la.l2_cid;
231 
232 	err = l2cap_do_connect(sk);
233 	if (err)
234 		goto done;
235 
236 wait:
237 	err = bt_sock_wait_state(sk, BT_CONNECTED,
238 			sock_sndtimeo(sk, flags & O_NONBLOCK));
239 done:
240 	release_sock(sk);
241 	return err;
242 }
243 
244 static int l2cap_sock_listen(struct socket *sock, int backlog)
245 {
246 	struct sock *sk = sock->sk;
247 	int err = 0;
248 
249 	BT_DBG("sk %p backlog %d", sk, backlog);
250 
251 	lock_sock(sk);
252 
253 	if ((sock->type != SOCK_SEQPACKET && sock->type != SOCK_STREAM)
254 			|| sk->sk_state != BT_BOUND) {
255 		err = -EBADFD;
256 		goto done;
257 	}
258 
259 	switch (l2cap_pi(sk)->mode) {
260 	case L2CAP_MODE_BASIC:
261 		break;
262 	case L2CAP_MODE_ERTM:
263 	case L2CAP_MODE_STREAMING:
264 		if (!disable_ertm)
265 			break;
266 		/* fall through */
267 	default:
268 		err = -ENOTSUPP;
269 		goto done;
270 	}
271 
272 	if (!l2cap_pi(sk)->psm && !l2cap_pi(sk)->dcid) {
273 		bdaddr_t *src = &bt_sk(sk)->src;
274 		u16 psm;
275 
276 		err = -EINVAL;
277 
278 		write_lock_bh(&l2cap_sk_list.lock);
279 
280 		for (psm = 0x1001; psm < 0x1100; psm += 2)
281 			if (!__l2cap_get_sock_by_addr(cpu_to_le16(psm), src)) {
282 				l2cap_pi(sk)->psm   = cpu_to_le16(psm);
283 				l2cap_pi(sk)->sport = cpu_to_le16(psm);
284 				err = 0;
285 				break;
286 			}
287 
288 		write_unlock_bh(&l2cap_sk_list.lock);
289 
290 		if (err < 0)
291 			goto done;
292 	}
293 
294 	sk->sk_max_ack_backlog = backlog;
295 	sk->sk_ack_backlog = 0;
296 	sk->sk_state = BT_LISTEN;
297 
298 done:
299 	release_sock(sk);
300 	return err;
301 }
302 
303 static int l2cap_sock_accept(struct socket *sock, struct socket *newsock, int flags)
304 {
305 	DECLARE_WAITQUEUE(wait, current);
306 	struct sock *sk = sock->sk, *nsk;
307 	long timeo;
308 	int err = 0;
309 
310 	lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
311 
312 	if (sk->sk_state != BT_LISTEN) {
313 		err = -EBADFD;
314 		goto done;
315 	}
316 
317 	timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
318 
319 	BT_DBG("sk %p timeo %ld", sk, timeo);
320 
321 	/* Wait for an incoming connection. (wake-one). */
322 	add_wait_queue_exclusive(sk_sleep(sk), &wait);
323 	while (!(nsk = bt_accept_dequeue(sk, newsock))) {
324 		set_current_state(TASK_INTERRUPTIBLE);
325 		if (!timeo) {
326 			err = -EAGAIN;
327 			break;
328 		}
329 
330 		release_sock(sk);
331 		timeo = schedule_timeout(timeo);
332 		lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
333 
334 		if (sk->sk_state != BT_LISTEN) {
335 			err = -EBADFD;
336 			break;
337 		}
338 
339 		if (signal_pending(current)) {
340 			err = sock_intr_errno(timeo);
341 			break;
342 		}
343 	}
344 	set_current_state(TASK_RUNNING);
345 	remove_wait_queue(sk_sleep(sk), &wait);
346 
347 	if (err)
348 		goto done;
349 
350 	newsock->state = SS_CONNECTED;
351 
352 	BT_DBG("new socket %p", nsk);
353 
354 done:
355 	release_sock(sk);
356 	return err;
357 }
358 
359 static int l2cap_sock_getname(struct socket *sock, struct sockaddr *addr, int *len, int peer)
360 {
361 	struct sockaddr_l2 *la = (struct sockaddr_l2 *) addr;
362 	struct sock *sk = sock->sk;
363 
364 	BT_DBG("sock %p, sk %p", sock, sk);
365 
366 	addr->sa_family = AF_BLUETOOTH;
367 	*len = sizeof(struct sockaddr_l2);
368 
369 	if (peer) {
370 		la->l2_psm = l2cap_pi(sk)->psm;
371 		bacpy(&la->l2_bdaddr, &bt_sk(sk)->dst);
372 		la->l2_cid = cpu_to_le16(l2cap_pi(sk)->dcid);
373 	} else {
374 		la->l2_psm = l2cap_pi(sk)->sport;
375 		bacpy(&la->l2_bdaddr, &bt_sk(sk)->src);
376 		la->l2_cid = cpu_to_le16(l2cap_pi(sk)->scid);
377 	}
378 
379 	return 0;
380 }
381 
382 static int l2cap_sock_getsockopt_old(struct socket *sock, int optname, char __user *optval, int __user *optlen)
383 {
384 	struct sock *sk = sock->sk;
385 	struct l2cap_options opts;
386 	struct l2cap_conninfo cinfo;
387 	int len, err = 0;
388 	u32 opt;
389 
390 	BT_DBG("sk %p", sk);
391 
392 	if (get_user(len, optlen))
393 		return -EFAULT;
394 
395 	lock_sock(sk);
396 
397 	switch (optname) {
398 	case L2CAP_OPTIONS:
399 		memset(&opts, 0, sizeof(opts));
400 		opts.imtu     = l2cap_pi(sk)->imtu;
401 		opts.omtu     = l2cap_pi(sk)->omtu;
402 		opts.flush_to = l2cap_pi(sk)->flush_to;
403 		opts.mode     = l2cap_pi(sk)->mode;
404 		opts.fcs      = l2cap_pi(sk)->fcs;
405 		opts.max_tx   = l2cap_pi(sk)->max_tx;
406 		opts.txwin_size = (__u16)l2cap_pi(sk)->tx_win;
407 
408 		len = min_t(unsigned int, len, sizeof(opts));
409 		if (copy_to_user(optval, (char *) &opts, len))
410 			err = -EFAULT;
411 
412 		break;
413 
414 	case L2CAP_LM:
415 		switch (l2cap_pi(sk)->sec_level) {
416 		case BT_SECURITY_LOW:
417 			opt = L2CAP_LM_AUTH;
418 			break;
419 		case BT_SECURITY_MEDIUM:
420 			opt = L2CAP_LM_AUTH | L2CAP_LM_ENCRYPT;
421 			break;
422 		case BT_SECURITY_HIGH:
423 			opt = L2CAP_LM_AUTH | L2CAP_LM_ENCRYPT |
424 							L2CAP_LM_SECURE;
425 			break;
426 		default:
427 			opt = 0;
428 			break;
429 		}
430 
431 		if (l2cap_pi(sk)->role_switch)
432 			opt |= L2CAP_LM_MASTER;
433 
434 		if (l2cap_pi(sk)->force_reliable)
435 			opt |= L2CAP_LM_RELIABLE;
436 
437 		if (put_user(opt, (u32 __user *) optval))
438 			err = -EFAULT;
439 		break;
440 
441 	case L2CAP_CONNINFO:
442 		if (sk->sk_state != BT_CONNECTED &&
443 					!(sk->sk_state == BT_CONNECT2 &&
444 						bt_sk(sk)->defer_setup)) {
445 			err = -ENOTCONN;
446 			break;
447 		}
448 
449 		cinfo.hci_handle = l2cap_pi(sk)->conn->hcon->handle;
450 		memcpy(cinfo.dev_class, l2cap_pi(sk)->conn->hcon->dev_class, 3);
451 
452 		len = min_t(unsigned int, len, sizeof(cinfo));
453 		if (copy_to_user(optval, (char *) &cinfo, len))
454 			err = -EFAULT;
455 
456 		break;
457 
458 	default:
459 		err = -ENOPROTOOPT;
460 		break;
461 	}
462 
463 	release_sock(sk);
464 	return err;
465 }
466 
467 static int l2cap_sock_getsockopt(struct socket *sock, int level, int optname, char __user *optval, int __user *optlen)
468 {
469 	struct sock *sk = sock->sk;
470 	struct bt_security sec;
471 	int len, err = 0;
472 
473 	BT_DBG("sk %p", sk);
474 
475 	if (level == SOL_L2CAP)
476 		return l2cap_sock_getsockopt_old(sock, optname, optval, optlen);
477 
478 	if (level != SOL_BLUETOOTH)
479 		return -ENOPROTOOPT;
480 
481 	if (get_user(len, optlen))
482 		return -EFAULT;
483 
484 	lock_sock(sk);
485 
486 	switch (optname) {
487 	case BT_SECURITY:
488 		if (sk->sk_type != SOCK_SEQPACKET && sk->sk_type != SOCK_STREAM
489 				&& sk->sk_type != SOCK_RAW) {
490 			err = -EINVAL;
491 			break;
492 		}
493 
494 		sec.level = l2cap_pi(sk)->sec_level;
495 
496 		len = min_t(unsigned int, len, sizeof(sec));
497 		if (copy_to_user(optval, (char *) &sec, len))
498 			err = -EFAULT;
499 
500 		break;
501 
502 	case BT_DEFER_SETUP:
503 		if (sk->sk_state != BT_BOUND && sk->sk_state != BT_LISTEN) {
504 			err = -EINVAL;
505 			break;
506 		}
507 
508 		if (put_user(bt_sk(sk)->defer_setup, (u32 __user *) optval))
509 			err = -EFAULT;
510 
511 		break;
512 
513 	case BT_FLUSHABLE:
514 		if (put_user(l2cap_pi(sk)->flushable, (u32 __user *) optval))
515 			err = -EFAULT;
516 
517 		break;
518 
519 	default:
520 		err = -ENOPROTOOPT;
521 		break;
522 	}
523 
524 	release_sock(sk);
525 	return err;
526 }
527 
528 static int l2cap_sock_setsockopt_old(struct socket *sock, int optname, char __user *optval, unsigned int optlen)
529 {
530 	struct sock *sk = sock->sk;
531 	struct l2cap_options opts;
532 	int len, err = 0;
533 	u32 opt;
534 
535 	BT_DBG("sk %p", sk);
536 
537 	lock_sock(sk);
538 
539 	switch (optname) {
540 	case L2CAP_OPTIONS:
541 		if (sk->sk_state == BT_CONNECTED) {
542 			err = -EINVAL;
543 			break;
544 		}
545 
546 		opts.imtu     = l2cap_pi(sk)->imtu;
547 		opts.omtu     = l2cap_pi(sk)->omtu;
548 		opts.flush_to = l2cap_pi(sk)->flush_to;
549 		opts.mode     = l2cap_pi(sk)->mode;
550 		opts.fcs      = l2cap_pi(sk)->fcs;
551 		opts.max_tx   = l2cap_pi(sk)->max_tx;
552 		opts.txwin_size = (__u16)l2cap_pi(sk)->tx_win;
553 
554 		len = min_t(unsigned int, sizeof(opts), optlen);
555 		if (copy_from_user((char *) &opts, optval, len)) {
556 			err = -EFAULT;
557 			break;
558 		}
559 
560 		if (opts.txwin_size > L2CAP_DEFAULT_TX_WINDOW) {
561 			err = -EINVAL;
562 			break;
563 		}
564 
565 		l2cap_pi(sk)->mode = opts.mode;
566 		switch (l2cap_pi(sk)->mode) {
567 		case L2CAP_MODE_BASIC:
568 			l2cap_pi(sk)->conf_state &= ~L2CAP_CONF_STATE2_DEVICE;
569 			break;
570 		case L2CAP_MODE_ERTM:
571 		case L2CAP_MODE_STREAMING:
572 			if (!disable_ertm)
573 				break;
574 			/* fall through */
575 		default:
576 			err = -EINVAL;
577 			break;
578 		}
579 
580 		l2cap_pi(sk)->imtu = opts.imtu;
581 		l2cap_pi(sk)->omtu = opts.omtu;
582 		l2cap_pi(sk)->fcs  = opts.fcs;
583 		l2cap_pi(sk)->max_tx = opts.max_tx;
584 		l2cap_pi(sk)->tx_win = (__u8)opts.txwin_size;
585 		break;
586 
587 	case L2CAP_LM:
588 		if (get_user(opt, (u32 __user *) optval)) {
589 			err = -EFAULT;
590 			break;
591 		}
592 
593 		if (opt & L2CAP_LM_AUTH)
594 			l2cap_pi(sk)->sec_level = BT_SECURITY_LOW;
595 		if (opt & L2CAP_LM_ENCRYPT)
596 			l2cap_pi(sk)->sec_level = BT_SECURITY_MEDIUM;
597 		if (opt & L2CAP_LM_SECURE)
598 			l2cap_pi(sk)->sec_level = BT_SECURITY_HIGH;
599 
600 		l2cap_pi(sk)->role_switch    = (opt & L2CAP_LM_MASTER);
601 		l2cap_pi(sk)->force_reliable = (opt & L2CAP_LM_RELIABLE);
602 		break;
603 
604 	default:
605 		err = -ENOPROTOOPT;
606 		break;
607 	}
608 
609 	release_sock(sk);
610 	return err;
611 }
612 
613 static int l2cap_sock_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen)
614 {
615 	struct sock *sk = sock->sk;
616 	struct bt_security sec;
617 	int len, err = 0;
618 	u32 opt;
619 
620 	BT_DBG("sk %p", sk);
621 
622 	if (level == SOL_L2CAP)
623 		return l2cap_sock_setsockopt_old(sock, optname, optval, optlen);
624 
625 	if (level != SOL_BLUETOOTH)
626 		return -ENOPROTOOPT;
627 
628 	lock_sock(sk);
629 
630 	switch (optname) {
631 	case BT_SECURITY:
632 		if (sk->sk_type != SOCK_SEQPACKET && sk->sk_type != SOCK_STREAM
633 				&& sk->sk_type != SOCK_RAW) {
634 			err = -EINVAL;
635 			break;
636 		}
637 
638 		sec.level = BT_SECURITY_LOW;
639 
640 		len = min_t(unsigned int, sizeof(sec), optlen);
641 		if (copy_from_user((char *) &sec, optval, len)) {
642 			err = -EFAULT;
643 			break;
644 		}
645 
646 		if (sec.level < BT_SECURITY_LOW ||
647 					sec.level > BT_SECURITY_HIGH) {
648 			err = -EINVAL;
649 			break;
650 		}
651 
652 		l2cap_pi(sk)->sec_level = sec.level;
653 		break;
654 
655 	case BT_DEFER_SETUP:
656 		if (sk->sk_state != BT_BOUND && sk->sk_state != BT_LISTEN) {
657 			err = -EINVAL;
658 			break;
659 		}
660 
661 		if (get_user(opt, (u32 __user *) optval)) {
662 			err = -EFAULT;
663 			break;
664 		}
665 
666 		bt_sk(sk)->defer_setup = opt;
667 		break;
668 
669 	case BT_FLUSHABLE:
670 		if (get_user(opt, (u32 __user *) optval)) {
671 			err = -EFAULT;
672 			break;
673 		}
674 
675 		if (opt > BT_FLUSHABLE_ON) {
676 			err = -EINVAL;
677 			break;
678 		}
679 
680 		if (opt == BT_FLUSHABLE_OFF) {
681 			struct l2cap_conn *conn = l2cap_pi(sk)->conn;
682 			/* proceed futher only when we have l2cap_conn and
683 			   No Flush support in the LM */
684 			if (!conn || !lmp_no_flush_capable(conn->hcon->hdev)) {
685 				err = -EINVAL;
686 				break;
687 			}
688 		}
689 
690 		l2cap_pi(sk)->flushable = opt;
691 		break;
692 
693 	default:
694 		err = -ENOPROTOOPT;
695 		break;
696 	}
697 
698 	release_sock(sk);
699 	return err;
700 }
701 
702 static int l2cap_sock_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg, size_t len)
703 {
704 	struct sock *sk = sock->sk;
705 	struct l2cap_pinfo *pi = l2cap_pi(sk);
706 	struct sk_buff *skb;
707 	u16 control;
708 	int err;
709 
710 	BT_DBG("sock %p, sk %p", sock, sk);
711 
712 	err = sock_error(sk);
713 	if (err)
714 		return err;
715 
716 	if (msg->msg_flags & MSG_OOB)
717 		return -EOPNOTSUPP;
718 
719 	lock_sock(sk);
720 
721 	if (sk->sk_state != BT_CONNECTED) {
722 		err = -ENOTCONN;
723 		goto done;
724 	}
725 
726 	/* Connectionless channel */
727 	if (sk->sk_type == SOCK_DGRAM) {
728 		skb = l2cap_create_connless_pdu(sk, msg, len);
729 		if (IS_ERR(skb)) {
730 			err = PTR_ERR(skb);
731 		} else {
732 			l2cap_do_send(sk, skb);
733 			err = len;
734 		}
735 		goto done;
736 	}
737 
738 	switch (pi->mode) {
739 	case L2CAP_MODE_BASIC:
740 		/* Check outgoing MTU */
741 		if (len > pi->omtu) {
742 			err = -EMSGSIZE;
743 			goto done;
744 		}
745 
746 		/* Create a basic PDU */
747 		skb = l2cap_create_basic_pdu(sk, msg, len);
748 		if (IS_ERR(skb)) {
749 			err = PTR_ERR(skb);
750 			goto done;
751 		}
752 
753 		l2cap_do_send(sk, skb);
754 		err = len;
755 		break;
756 
757 	case L2CAP_MODE_ERTM:
758 	case L2CAP_MODE_STREAMING:
759 		/* Entire SDU fits into one PDU */
760 		if (len <= pi->chan->remote_mps) {
761 			control = L2CAP_SDU_UNSEGMENTED;
762 			skb = l2cap_create_iframe_pdu(sk, msg, len, control, 0);
763 			if (IS_ERR(skb)) {
764 				err = PTR_ERR(skb);
765 				goto done;
766 			}
767 			__skb_queue_tail(TX_QUEUE(sk), skb);
768 
769 			if (sk->sk_send_head == NULL)
770 				sk->sk_send_head = skb;
771 
772 		} else {
773 		/* Segment SDU into multiples PDUs */
774 			err = l2cap_sar_segment_sdu(pi->chan, msg, len);
775 			if (err < 0)
776 				goto done;
777 		}
778 
779 		if (pi->mode == L2CAP_MODE_STREAMING) {
780 			l2cap_streaming_send(pi->chan);
781 			err = len;
782 			break;
783 		}
784 
785 		if ((pi->chan->conn_state & L2CAP_CONN_REMOTE_BUSY) &&
786 				(pi->chan->conn_state & L2CAP_CONN_WAIT_F)) {
787 			err = len;
788 			break;
789 		}
790 		err = l2cap_ertm_send(pi->chan);
791 
792 		if (err >= 0)
793 			err = len;
794 		break;
795 
796 	default:
797 		BT_DBG("bad state %1.1x", pi->mode);
798 		err = -EBADFD;
799 	}
800 
801 done:
802 	release_sock(sk);
803 	return err;
804 }
805 
806 static int l2cap_sock_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg, size_t len, int flags)
807 {
808 	struct sock *sk = sock->sk;
809 
810 	lock_sock(sk);
811 
812 	if (sk->sk_state == BT_CONNECT2 && bt_sk(sk)->defer_setup) {
813 		__l2cap_connect_rsp_defer(sk);
814 		release_sock(sk);
815 		return 0;
816 	}
817 
818 	release_sock(sk);
819 
820 	if (sock->type == SOCK_STREAM)
821 		return bt_sock_stream_recvmsg(iocb, sock, msg, len, flags);
822 
823 	return bt_sock_recvmsg(iocb, sock, msg, len, flags);
824 }
825 
826 /* Kill socket (only if zapped and orphan)
827  * Must be called on unlocked socket.
828  */
829 void l2cap_sock_kill(struct sock *sk)
830 {
831 	if (!sock_flag(sk, SOCK_ZAPPED) || sk->sk_socket)
832 		return;
833 
834 	BT_DBG("sk %p state %d", sk, sk->sk_state);
835 
836 	/* Kill poor orphan */
837 	bt_sock_unlink(&l2cap_sk_list, sk);
838 	sock_set_flag(sk, SOCK_DEAD);
839 	sock_put(sk);
840 }
841 
842 /* Must be called on unlocked socket. */
843 static void l2cap_sock_close(struct sock *sk)
844 {
845 	l2cap_sock_clear_timer(sk);
846 	lock_sock(sk);
847 	__l2cap_sock_close(sk, ECONNRESET);
848 	release_sock(sk);
849 	l2cap_sock_kill(sk);
850 }
851 
852 static void l2cap_sock_cleanup_listen(struct sock *parent)
853 {
854 	struct sock *sk;
855 
856 	BT_DBG("parent %p", parent);
857 
858 	/* Close not yet accepted channels */
859 	while ((sk = bt_accept_dequeue(parent, NULL)))
860 		l2cap_sock_close(sk);
861 
862 	parent->sk_state = BT_CLOSED;
863 	sock_set_flag(parent, SOCK_ZAPPED);
864 }
865 
866 void __l2cap_sock_close(struct sock *sk, int reason)
867 {
868 	struct l2cap_conn *conn = l2cap_pi(sk)->conn;
869 	struct l2cap_chan *chan = l2cap_pi(sk)->chan;
870 
871 	BT_DBG("sk %p state %d socket %p", sk, sk->sk_state, sk->sk_socket);
872 
873 	switch (sk->sk_state) {
874 	case BT_LISTEN:
875 		l2cap_sock_cleanup_listen(sk);
876 		break;
877 
878 	case BT_CONNECTED:
879 	case BT_CONFIG:
880 		if ((sk->sk_type == SOCK_SEQPACKET ||
881 					sk->sk_type == SOCK_STREAM) &&
882 					conn->hcon->type == ACL_LINK) {
883 			l2cap_sock_set_timer(sk, sk->sk_sndtimeo);
884 			l2cap_send_disconn_req(conn, chan, reason);
885 		} else
886 			l2cap_chan_del(chan, reason);
887 		break;
888 
889 	case BT_CONNECT2:
890 		if ((sk->sk_type == SOCK_SEQPACKET ||
891 					sk->sk_type == SOCK_STREAM) &&
892 					conn->hcon->type == ACL_LINK) {
893 			struct l2cap_conn_rsp rsp;
894 			__u16 result;
895 
896 			if (bt_sk(sk)->defer_setup)
897 				result = L2CAP_CR_SEC_BLOCK;
898 			else
899 				result = L2CAP_CR_BAD_PSM;
900 
901 			rsp.scid   = cpu_to_le16(l2cap_pi(sk)->dcid);
902 			rsp.dcid   = cpu_to_le16(l2cap_pi(sk)->scid);
903 			rsp.result = cpu_to_le16(result);
904 			rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
905 			l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
906 							sizeof(rsp), &rsp);
907 		}
908 
909 		l2cap_chan_del(chan, reason);
910 		break;
911 
912 	case BT_CONNECT:
913 	case BT_DISCONN:
914 		l2cap_chan_del(chan, reason);
915 		break;
916 
917 	default:
918 		sock_set_flag(sk, SOCK_ZAPPED);
919 		break;
920 	}
921 }
922 
923 static int l2cap_sock_shutdown(struct socket *sock, int how)
924 {
925 	struct sock *sk = sock->sk;
926 	int err = 0;
927 
928 	BT_DBG("sock %p, sk %p", sock, sk);
929 
930 	if (!sk)
931 		return 0;
932 
933 	lock_sock(sk);
934 	if (!sk->sk_shutdown) {
935 		if (l2cap_pi(sk)->mode == L2CAP_MODE_ERTM)
936 			err = __l2cap_wait_ack(sk);
937 
938 		sk->sk_shutdown = SHUTDOWN_MASK;
939 		l2cap_sock_clear_timer(sk);
940 		__l2cap_sock_close(sk, 0);
941 
942 		if (sock_flag(sk, SOCK_LINGER) && sk->sk_lingertime)
943 			err = bt_sock_wait_state(sk, BT_CLOSED,
944 							sk->sk_lingertime);
945 	}
946 
947 	if (!err && sk->sk_err)
948 		err = -sk->sk_err;
949 
950 	release_sock(sk);
951 	return err;
952 }
953 
954 static int l2cap_sock_release(struct socket *sock)
955 {
956 	struct sock *sk = sock->sk;
957 	int err;
958 
959 	BT_DBG("sock %p, sk %p", sock, sk);
960 
961 	if (!sk)
962 		return 0;
963 
964 	err = l2cap_sock_shutdown(sock, 2);
965 
966 	sock_orphan(sk);
967 	l2cap_sock_kill(sk);
968 	return err;
969 }
970 
971 static void l2cap_sock_destruct(struct sock *sk)
972 {
973 	BT_DBG("sk %p", sk);
974 
975 	skb_queue_purge(&sk->sk_receive_queue);
976 	skb_queue_purge(&sk->sk_write_queue);
977 }
978 
979 void l2cap_sock_init(struct sock *sk, struct sock *parent)
980 {
981 	struct l2cap_pinfo *pi = l2cap_pi(sk);
982 
983 	BT_DBG("sk %p", sk);
984 
985 	if (parent) {
986 		sk->sk_type = parent->sk_type;
987 		bt_sk(sk)->defer_setup = bt_sk(parent)->defer_setup;
988 
989 		pi->imtu = l2cap_pi(parent)->imtu;
990 		pi->omtu = l2cap_pi(parent)->omtu;
991 		pi->conf_state = l2cap_pi(parent)->conf_state;
992 		pi->mode = l2cap_pi(parent)->mode;
993 		pi->fcs  = l2cap_pi(parent)->fcs;
994 		pi->max_tx = l2cap_pi(parent)->max_tx;
995 		pi->tx_win = l2cap_pi(parent)->tx_win;
996 		pi->sec_level = l2cap_pi(parent)->sec_level;
997 		pi->role_switch = l2cap_pi(parent)->role_switch;
998 		pi->force_reliable = l2cap_pi(parent)->force_reliable;
999 		pi->flushable = l2cap_pi(parent)->flushable;
1000 	} else {
1001 		pi->imtu = L2CAP_DEFAULT_MTU;
1002 		pi->omtu = 0;
1003 		if (!disable_ertm && sk->sk_type == SOCK_STREAM) {
1004 			pi->mode = L2CAP_MODE_ERTM;
1005 			pi->conf_state |= L2CAP_CONF_STATE2_DEVICE;
1006 		} else {
1007 			pi->mode = L2CAP_MODE_BASIC;
1008 		}
1009 		pi->max_tx = L2CAP_DEFAULT_MAX_TX;
1010 		pi->fcs  = L2CAP_FCS_CRC16;
1011 		pi->tx_win = L2CAP_DEFAULT_TX_WINDOW;
1012 		pi->sec_level = BT_SECURITY_LOW;
1013 		pi->role_switch = 0;
1014 		pi->force_reliable = 0;
1015 		pi->flushable = BT_FLUSHABLE_OFF;
1016 	}
1017 
1018 	/* Default config options */
1019 	pi->flush_to = L2CAP_DEFAULT_FLUSH_TO;
1020 	skb_queue_head_init(TX_QUEUE(sk));
1021 }
1022 
1023 static struct proto l2cap_proto = {
1024 	.name		= "L2CAP",
1025 	.owner		= THIS_MODULE,
1026 	.obj_size	= sizeof(struct l2cap_pinfo)
1027 };
1028 
1029 struct sock *l2cap_sock_alloc(struct net *net, struct socket *sock, int proto, gfp_t prio)
1030 {
1031 	struct sock *sk;
1032 
1033 	sk = sk_alloc(net, PF_BLUETOOTH, prio, &l2cap_proto);
1034 	if (!sk)
1035 		return NULL;
1036 
1037 	sock_init_data(sock, sk);
1038 	INIT_LIST_HEAD(&bt_sk(sk)->accept_q);
1039 
1040 	sk->sk_destruct = l2cap_sock_destruct;
1041 	sk->sk_sndtimeo = msecs_to_jiffies(L2CAP_CONN_TIMEOUT);
1042 
1043 	sock_reset_flag(sk, SOCK_ZAPPED);
1044 
1045 	sk->sk_protocol = proto;
1046 	sk->sk_state = BT_OPEN;
1047 
1048 	setup_timer(&sk->sk_timer, l2cap_sock_timeout, (unsigned long) sk);
1049 
1050 	bt_sock_link(&l2cap_sk_list, sk);
1051 	return sk;
1052 }
1053 
1054 static int l2cap_sock_create(struct net *net, struct socket *sock, int protocol,
1055 			     int kern)
1056 {
1057 	struct sock *sk;
1058 
1059 	BT_DBG("sock %p", sock);
1060 
1061 	sock->state = SS_UNCONNECTED;
1062 
1063 	if (sock->type != SOCK_SEQPACKET && sock->type != SOCK_STREAM &&
1064 			sock->type != SOCK_DGRAM && sock->type != SOCK_RAW)
1065 		return -ESOCKTNOSUPPORT;
1066 
1067 	if (sock->type == SOCK_RAW && !kern && !capable(CAP_NET_RAW))
1068 		return -EPERM;
1069 
1070 	sock->ops = &l2cap_sock_ops;
1071 
1072 	sk = l2cap_sock_alloc(net, sock, protocol, GFP_ATOMIC);
1073 	if (!sk)
1074 		return -ENOMEM;
1075 
1076 	l2cap_sock_init(sk, NULL);
1077 	return 0;
1078 }
1079 
1080 const struct proto_ops l2cap_sock_ops = {
1081 	.family		= PF_BLUETOOTH,
1082 	.owner		= THIS_MODULE,
1083 	.release	= l2cap_sock_release,
1084 	.bind		= l2cap_sock_bind,
1085 	.connect	= l2cap_sock_connect,
1086 	.listen		= l2cap_sock_listen,
1087 	.accept		= l2cap_sock_accept,
1088 	.getname	= l2cap_sock_getname,
1089 	.sendmsg	= l2cap_sock_sendmsg,
1090 	.recvmsg	= l2cap_sock_recvmsg,
1091 	.poll		= bt_sock_poll,
1092 	.ioctl		= bt_sock_ioctl,
1093 	.mmap		= sock_no_mmap,
1094 	.socketpair	= sock_no_socketpair,
1095 	.shutdown	= l2cap_sock_shutdown,
1096 	.setsockopt	= l2cap_sock_setsockopt,
1097 	.getsockopt	= l2cap_sock_getsockopt
1098 };
1099 
1100 static const struct net_proto_family l2cap_sock_family_ops = {
1101 	.family	= PF_BLUETOOTH,
1102 	.owner	= THIS_MODULE,
1103 	.create	= l2cap_sock_create,
1104 };
1105 
1106 int __init l2cap_init_sockets(void)
1107 {
1108 	int err;
1109 
1110 	err = proto_register(&l2cap_proto, 0);
1111 	if (err < 0)
1112 		return err;
1113 
1114 	err = bt_sock_register(BTPROTO_L2CAP, &l2cap_sock_family_ops);
1115 	if (err < 0)
1116 		goto error;
1117 
1118 	BT_INFO("L2CAP socket layer initialized");
1119 
1120 	return 0;
1121 
1122 error:
1123 	BT_ERR("L2CAP socket registration failed");
1124 	proto_unregister(&l2cap_proto);
1125 	return err;
1126 }
1127 
1128 void l2cap_cleanup_sockets(void)
1129 {
1130 	if (bt_sock_unregister(BTPROTO_L2CAP) < 0)
1131 		BT_ERR("L2CAP socket unregistration failed");
1132 
1133 	proto_unregister(&l2cap_proto);
1134 }
1135