xref: /netbsd-src/sys/netbt/l2cap_upper.c (revision 271138cb3a6de667c600b54c1d0896e7b41a929b)
1 /*	$NetBSD: l2cap_upper.c,v 1.10 2009/09/25 19:44:57 plunky Exp $	*/
2 
3 /*-
4  * Copyright (c) 2005 Iain Hibbert.
5  * Copyright (c) 2006 Itronix Inc.
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. The name of Itronix Inc. may not be used to endorse
17  *    or promote products derived from this software without specific
18  *    prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY ITRONIX INC. ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
22  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL ITRONIX INC. BE LIABLE FOR ANY
24  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
25  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
26  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
27  * ON ANY THEORY OF LIABILITY, WHETHER IN
28  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30  * POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 #include <sys/cdefs.h>
34 __KERNEL_RCSID(0, "$NetBSD: l2cap_upper.c,v 1.10 2009/09/25 19:44:57 plunky Exp $");
35 
36 #include <sys/param.h>
37 #include <sys/kernel.h>
38 #include <sys/mbuf.h>
39 #include <sys/proc.h>
40 #include <sys/queue.h>
41 #include <sys/socket.h>
42 #include <sys/socketvar.h>
43 #include <sys/systm.h>
44 
45 #include <netbt/bluetooth.h>
46 #include <netbt/hci.h>
47 #include <netbt/l2cap.h>
48 
49 /*******************************************************************************
50  *
51  *	L2CAP Channel - Upper Protocol API
52  */
53 
54 /*
55  * l2cap_attach(handle, btproto, upper)
56  *
57  *	attach new l2cap_channel to handle, populate
58  *	with reasonable defaults
59  */
60 int
61 l2cap_attach(struct l2cap_channel **handle,
62 		const struct btproto *proto, void *upper)
63 {
64 	struct l2cap_channel *chan;
65 
66 	KASSERT(handle != NULL);
67 	KASSERT(proto != NULL);
68 	KASSERT(upper != NULL);
69 
70 	chan = malloc(sizeof(struct l2cap_channel), M_BLUETOOTH,
71 			M_NOWAIT | M_ZERO);
72 	if (chan == NULL)
73 		return ENOMEM;
74 
75 	chan->lc_proto = proto;
76 	chan->lc_upper = upper;
77 
78 	chan->lc_state = L2CAP_CLOSED;
79 
80 	chan->lc_lcid = L2CAP_NULL_CID;
81 	chan->lc_rcid = L2CAP_NULL_CID;
82 
83 	chan->lc_laddr.bt_len = sizeof(struct sockaddr_bt);
84 	chan->lc_laddr.bt_family = AF_BLUETOOTH;
85 	chan->lc_laddr.bt_psm = L2CAP_PSM_ANY;
86 
87 	chan->lc_raddr.bt_len = sizeof(struct sockaddr_bt);
88 	chan->lc_raddr.bt_family = AF_BLUETOOTH;
89 	chan->lc_raddr.bt_psm = L2CAP_PSM_ANY;
90 
91 	chan->lc_imtu = L2CAP_MTU_DEFAULT;
92 	chan->lc_omtu = L2CAP_MTU_DEFAULT;
93 	chan->lc_flush = L2CAP_FLUSH_TIMO_DEFAULT;
94 
95 	memcpy(&chan->lc_iqos, &l2cap_default_qos, sizeof(l2cap_qos_t));
96 	memcpy(&chan->lc_oqos, &l2cap_default_qos, sizeof(l2cap_qos_t));
97 
98 	MBUFQ_INIT(&chan->lc_txq);
99 
100 	*handle = chan;
101 	return 0;
102 }
103 
104 /*
105  * l2cap_bind(l2cap_channel, sockaddr)
106  *
107  *	set local address of channel
108  */
109 int
110 l2cap_bind(struct l2cap_channel *chan, struct sockaddr_bt *addr)
111 {
112 
113 	memcpy(&chan->lc_laddr, addr, sizeof(struct sockaddr_bt));
114 	return 0;
115 }
116 
117 /*
118  * l2cap_sockaddr(l2cap_channel, sockaddr)
119  *
120  *	get local address of channel
121  */
122 int
123 l2cap_sockaddr(struct l2cap_channel *chan, struct sockaddr_bt *addr)
124 {
125 
126 	memcpy(addr, &chan->lc_laddr, sizeof(struct sockaddr_bt));
127 	return 0;
128 }
129 
130 /*
131  * l2cap_connect(l2cap_channel, sockaddr)
132  *
133  *	Initiate a connection to destination. This corresponds to
134  *	"Open Channel Request" in the L2CAP specification and will
135  *	result in one of the following:
136  *
137  *		proto->connected(upper)
138  *		proto->disconnected(upper, error)
139  *
140  *	and, optionally
141  *		proto->connecting(upper)
142  */
143 int
144 l2cap_connect(struct l2cap_channel *chan, struct sockaddr_bt *dest)
145 {
146 	struct hci_unit *unit;
147 	int err;
148 
149 	memcpy(&chan->lc_raddr, dest, sizeof(struct sockaddr_bt));
150 
151 	if (L2CAP_PSM_INVALID(chan->lc_raddr.bt_psm))
152 		return EINVAL;
153 
154 	if (bdaddr_any(&chan->lc_raddr.bt_bdaddr))
155 		return EDESTADDRREQ;
156 
157 	/* set local address if it needs setting */
158 	if (bdaddr_any(&chan->lc_laddr.bt_bdaddr)) {
159 		err = hci_route_lookup(&chan->lc_laddr.bt_bdaddr,
160 					&chan->lc_raddr.bt_bdaddr);
161 		if (err)
162 			return err;
163 	}
164 
165 	unit = hci_unit_lookup(&chan->lc_laddr.bt_bdaddr);
166 	if (unit == NULL)
167 		return EHOSTUNREACH;
168 
169 	/* attach to active list */
170 	err = l2cap_cid_alloc(chan);
171 	if (err)
172 		return err;
173 
174 	/* open link to remote device */
175 	chan->lc_link = hci_acl_open(unit, &chan->lc_raddr.bt_bdaddr);
176 	if (chan->lc_link == NULL)
177 		return EHOSTUNREACH;
178 
179 	/* set the link mode */
180 	err = l2cap_setmode(chan);
181 	if (err == EINPROGRESS) {
182 		chan->lc_state = L2CAP_WAIT_SEND_CONNECT_REQ;
183 		(*chan->lc_proto->connecting)(chan->lc_upper);
184 		return 0;
185 	}
186 	if (err)
187 		goto fail;
188 
189 	/*
190 	 * We can queue a connect request now even though the link may
191 	 * not yet be open; Our mode setting is assured, and the queue
192 	 * will be started automatically at the right time.
193 	 */
194 	chan->lc_state = L2CAP_WAIT_RECV_CONNECT_RSP;
195 	err = l2cap_send_connect_req(chan);
196 	if (err)
197 		goto fail;
198 
199 	return 0;
200 
201 fail:
202 	chan->lc_state = L2CAP_CLOSED;
203 	hci_acl_close(chan->lc_link, err);
204 	chan->lc_link = NULL;
205 	return err;
206 }
207 
208 /*
209  * l2cap_peeraddr(l2cap_channel, sockaddr)
210  *
211  *	get remote address of channel
212  */
213 int
214 l2cap_peeraddr(struct l2cap_channel *chan, struct sockaddr_bt *addr)
215 {
216 
217 	memcpy(addr, &chan->lc_raddr, sizeof(struct sockaddr_bt));
218 	return 0;
219 }
220 
221 /*
222  * l2cap_disconnect(l2cap_channel, linger)
223  *
224  *	Initiate L2CAP disconnection. This corresponds to
225  *	"Close Channel Request" in the L2CAP specification
226  *	and will result in a call to
227  *
228  *		proto->disconnected(upper, error)
229  *
230  *	when the disconnection is complete. If linger is set,
231  *	the call will not be made until data has flushed from
232  *	the queue.
233  */
234 int
235 l2cap_disconnect(struct l2cap_channel *chan, int linger)
236 {
237 	int err = 0;
238 
239 	if (chan->lc_state == L2CAP_CLOSED
240 	    || chan->lc_state == L2CAP_WAIT_DISCONNECT)
241 		return EINVAL;
242 
243 	chan->lc_flags |= L2CAP_SHUTDOWN;
244 
245 	/*
246 	 * no need to do anything unless the queue is empty or
247 	 * we are not lingering..
248 	 */
249 	if ((MBUFQ_FIRST(&chan->lc_txq) == NULL && chan->lc_pending == 0)
250 	    || linger == 0) {
251 		chan->lc_state = L2CAP_WAIT_DISCONNECT;
252 		err = l2cap_send_disconnect_req(chan);
253 		if (err)
254 			l2cap_close(chan, err);
255 	}
256 	return err;
257 }
258 
259 /*
260  * l2cap_detach(handle)
261  *
262  *	Detach l2cap channel from handle & close it down
263  */
264 int
265 l2cap_detach(struct l2cap_channel **handle)
266 {
267 	struct l2cap_channel *chan;
268 
269 	chan = *handle;
270 	*handle = NULL;
271 
272 	if (chan->lc_state != L2CAP_CLOSED)
273 		l2cap_close(chan, 0);
274 
275 	if (chan->lc_lcid != L2CAP_NULL_CID) {
276 		LIST_REMOVE(chan, lc_ncid);
277 		chan->lc_lcid = L2CAP_NULL_CID;
278 	}
279 
280 	MBUFQ_DRAIN(&chan->lc_txq);
281 
282 	/*
283 	 * Could implement some kind of delayed expunge to make sure that the
284 	 * CID is really dead before it becomes available for reuse?
285 	 */
286 
287 	free(chan, M_BLUETOOTH);
288 	return 0;
289 }
290 
291 /*
292  * l2cap_listen(l2cap_channel)
293  *
294  *	Use this channel as a listening post (until detached). This will
295  *	result in calls to:
296  *
297  *		proto->newconn(upper, laddr, raddr)
298  *
299  *	for incoming connections matching the psm and local address of
300  *	the channel. NULL address is permitted and matches any device.
301  *	If L2CAP_PSM_ANY is bound the next higher unused value from the
302  *	dynamic range (above 0x1001) will be selected.
303  *
304  *	The upper layer should create and return a new channel.
305  *
306  *	You cannot use this channel for anything else subsequent to this call
307  */
308 int
309 l2cap_listen(struct l2cap_channel *chan)
310 {
311 	struct l2cap_channel *used, *prev = NULL;
312 	uint32_t psm;
313 
314 	if (chan->lc_lcid != L2CAP_NULL_CID)
315 		return EINVAL;
316 
317 	/*
318 	 * This is simplistic but its not really worth spending a
319 	 * lot of time looking for an unused PSM..
320 	 */
321 	if (chan->lc_laddr.bt_psm == L2CAP_PSM_ANY) {
322 		psm = 0x1001;
323 		used = LIST_FIRST(&l2cap_listen_list);
324 
325 		if (used != NULL && used->lc_laddr.bt_psm >= psm) {
326 			psm = used->lc_laddr.bt_psm + 0x0002;
327 			if ((psm & 0x0100) != 0)
328 				psm += 0x0100;
329 
330 			if (psm > UINT16_MAX)
331 				return EADDRNOTAVAIL;
332 		}
333 
334 		chan->lc_laddr.bt_psm = psm;
335 	} else if (L2CAP_PSM_INVALID(chan->lc_laddr.bt_psm))
336 		return EINVAL;
337 
338 	/*
339 	 * This CID is irrelevant, as the channel is not stored on the active
340 	 * list and the socket code does not allow operations on listening
341 	 * sockets, but we set it so the detach code knows to LIST_REMOVE the
342 	 * channel.
343 	 */
344 	chan->lc_lcid = L2CAP_SIGNAL_CID;
345 
346 	/*
347 	 * The list of listening channels is stored in an order such that new
348 	 * listeners dont usurp current listeners, but that specific listening
349 	 * takes precedence over promiscuous, and the connect request code can
350 	 * easily use the first matching entry.
351 	 */
352 	LIST_FOREACH(used, &l2cap_listen_list, lc_ncid) {
353 		if (used->lc_laddr.bt_psm < chan->lc_laddr.bt_psm)
354 			break;
355 
356 		if (used->lc_laddr.bt_psm == chan->lc_laddr.bt_psm
357 			&& bdaddr_any(&used->lc_laddr.bt_bdaddr)
358 			&& !bdaddr_any(&chan->lc_laddr.bt_bdaddr))
359 			break;
360 
361 		prev = used;
362 	}
363 
364 	if (prev == NULL)
365 		LIST_INSERT_HEAD(&l2cap_listen_list, chan, lc_ncid);
366 	else
367 		LIST_INSERT_AFTER(prev, chan, lc_ncid);
368 
369 	return 0;
370 }
371 
372 /*
373  * l2cap_send(l2cap_channel, mbuf)
374  *
375  *	Output SDU on channel described by channel. This corresponds
376  *	to "Send Data Request" in the L2CAP specification. The upper
377  *	layer will be notified when SDU's have completed sending by a
378  *	call to:
379  *
380  *		proto->complete(upper, n)
381  *
382  *	(currently n == 1)
383  *
384  *	Note: I'm not sure how this will work out, but I think that
385  *	if outgoing Retransmission Mode or Flow Control Mode is
386  *	negotiated then this call will not be made until the SDU has
387  *	been acknowleged by the peer L2CAP entity. For 'Best Effort'
388  *	it will be made when the packet has cleared the controller
389  *	buffers.
390  *
391  *	We only support Basic mode so far, so encapsulate with a
392  *	B-Frame header and start sending if we are not already
393  */
394 int
395 l2cap_send(struct l2cap_channel *chan, struct mbuf *m)
396 {
397 	l2cap_hdr_t *hdr;
398 	int plen;
399 
400 	if (chan->lc_state == L2CAP_CLOSED) {
401 		m_freem(m);
402 		return ENOTCONN;
403 	}
404 
405 	plen = m->m_pkthdr.len;
406 
407 	DPRINTFN(5, "send %d bytes on CID #%d (pending = %d)\n",
408 		plen, chan->lc_lcid, chan->lc_pending);
409 
410 	/* Encapsulate with B-Frame */
411 	M_PREPEND(m, sizeof(l2cap_hdr_t), M_DONTWAIT);
412 	if (m == NULL)
413 		return ENOMEM;
414 
415 	hdr = mtod(m, l2cap_hdr_t *);
416 	hdr->length = htole16(plen);
417 	hdr->dcid = htole16(chan->lc_rcid);
418 
419 	/* Queue it on our list */
420 	MBUFQ_ENQUEUE(&chan->lc_txq, m);
421 
422 	/* If we are not sending, then start doing so */
423 	if (chan->lc_pending == 0)
424 		return l2cap_start(chan);
425 
426 	return 0;
427 }
428 
429 /*
430  * l2cap_setopt(l2cap_channel, sopt)
431  *
432  *	Apply configuration options to channel. This corresponds to
433  *	"Configure Channel Request" in the L2CAP specification.
434  *
435  *	for SO_L2CAP_LM, the settings will take effect when the
436  *	channel is established. If the channel is already open,
437  *	a call to
438  *		proto->linkmode(upper, new)
439  *
440  *	will be made when the change is complete.
441  */
442 int
443 l2cap_setopt(struct l2cap_channel *chan, const struct sockopt *sopt)
444 {
445 	int mode, err = 0;
446 	uint16_t mtu;
447 
448 	switch (sopt->sopt_name) {
449 	case SO_L2CAP_IMTU:	/* set Incoming MTU */
450 		err = sockopt_get(sopt, &mtu, sizeof(mtu));
451 		if (err)
452 			break;
453 
454 		if (mtu < L2CAP_MTU_MINIMUM)
455 			err = EINVAL;
456 		else if (chan->lc_state == L2CAP_CLOSED)
457 			chan->lc_imtu = mtu;
458 		else
459 			err = EBUSY;
460 
461 		break;
462 
463 	case SO_L2CAP_LM:	/* set link mode */
464 		err = sockopt_getint(sopt, &mode);
465 		if (err)
466 			break;
467 
468 		mode &= (L2CAP_LM_SECURE | L2CAP_LM_ENCRYPT | L2CAP_LM_AUTH);
469 
470 		if (mode & L2CAP_LM_SECURE)
471 			mode |= L2CAP_LM_ENCRYPT;
472 
473 		if (mode & L2CAP_LM_ENCRYPT)
474 			mode |= L2CAP_LM_AUTH;
475 
476 		chan->lc_mode = mode;
477 
478 		if (chan->lc_state == L2CAP_OPEN)
479 			err = l2cap_setmode(chan);
480 
481 		break;
482 
483 	case SO_L2CAP_OQOS:	/* set Outgoing QoS flow spec */
484 	case SO_L2CAP_FLUSH:	/* set Outgoing Flush Timeout */
485 	default:
486 		err = ENOPROTOOPT;
487 		break;
488 	}
489 
490 	return err;
491 }
492 
493 /*
494  * l2cap_getopt(l2cap_channel, sopt)
495  *
496  *	Return configuration parameters.
497  */
498 int
499 l2cap_getopt(struct l2cap_channel *chan, struct sockopt *sopt)
500 {
501 
502 	switch (sopt->sopt_name) {
503 	case SO_L2CAP_IMTU:	/* get Incoming MTU */
504 		return sockopt_set(sopt, &chan->lc_imtu, sizeof(uint16_t));
505 
506 	case SO_L2CAP_OMTU:	/* get Outgoing MTU */
507 		return sockopt_set(sopt, &chan->lc_omtu, sizeof(uint16_t));
508 
509 	case SO_L2CAP_IQOS:	/* get Incoming QoS flow spec */
510 		return sockopt_set(sopt, &chan->lc_iqos, sizeof(l2cap_qos_t));
511 
512 	case SO_L2CAP_OQOS:	/* get Outgoing QoS flow spec */
513 		return sockopt_set(sopt, &chan->lc_oqos, sizeof(l2cap_qos_t));
514 
515 	case SO_L2CAP_FLUSH:	/* get Flush Timeout */
516 		return sockopt_set(sopt, &chan->lc_flush, sizeof(uint16_t));
517 
518 	case SO_L2CAP_LM:	/* get link mode */
519 		return sockopt_setint(sopt, chan->lc_mode);
520 
521 	default:
522 		break;
523 	}
524 
525 	return ENOPROTOOPT;
526 }
527