xref: /netbsd-src/sys/netbt/l2cap_upper.c (revision b1c86f5f087524e68db12794ee9c3e3da1ab17a0)
1 /*	$NetBSD: l2cap_upper.c,v 1.11 2010/01/04 19:20:05 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 1.11 2010/01/04 19:20:05 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 	if (chan->lc_lcid != L2CAP_NULL_CID)
114 		return EINVAL;
115 
116 	memcpy(&chan->lc_laddr, addr, sizeof(struct sockaddr_bt));
117 	return 0;
118 }
119 
120 /*
121  * l2cap_sockaddr(l2cap_channel, sockaddr)
122  *
123  *	get local address of channel
124  */
125 int
126 l2cap_sockaddr(struct l2cap_channel *chan, struct sockaddr_bt *addr)
127 {
128 
129 	memcpy(addr, &chan->lc_laddr, sizeof(struct sockaddr_bt));
130 	return 0;
131 }
132 
133 /*
134  * l2cap_connect(l2cap_channel, sockaddr)
135  *
136  *	Initiate a connection to destination. This corresponds to
137  *	"Open Channel Request" in the L2CAP specification and will
138  *	result in one of the following:
139  *
140  *		proto->connected(upper)
141  *		proto->disconnected(upper, error)
142  *
143  *	and, optionally
144  *		proto->connecting(upper)
145  */
146 int
147 l2cap_connect(struct l2cap_channel *chan, struct sockaddr_bt *dest)
148 {
149 	struct hci_unit *unit;
150 	int err;
151 
152 	memcpy(&chan->lc_raddr, dest, sizeof(struct sockaddr_bt));
153 
154 	if (L2CAP_PSM_INVALID(chan->lc_raddr.bt_psm))
155 		return EINVAL;
156 
157 	if (bdaddr_any(&chan->lc_raddr.bt_bdaddr))
158 		return EDESTADDRREQ;
159 
160 	/* set local address if it needs setting */
161 	if (bdaddr_any(&chan->lc_laddr.bt_bdaddr)) {
162 		err = hci_route_lookup(&chan->lc_laddr.bt_bdaddr,
163 					&chan->lc_raddr.bt_bdaddr);
164 		if (err)
165 			return err;
166 	}
167 
168 	unit = hci_unit_lookup(&chan->lc_laddr.bt_bdaddr);
169 	if (unit == NULL)
170 		return EHOSTUNREACH;
171 
172 	/* attach to active list */
173 	err = l2cap_cid_alloc(chan);
174 	if (err)
175 		return err;
176 
177 	/* open link to remote device */
178 	chan->lc_link = hci_acl_open(unit, &chan->lc_raddr.bt_bdaddr);
179 	if (chan->lc_link == NULL)
180 		return EHOSTUNREACH;
181 
182 	/* set the link mode */
183 	err = l2cap_setmode(chan);
184 	if (err == EINPROGRESS) {
185 		chan->lc_state = L2CAP_WAIT_SEND_CONNECT_REQ;
186 		(*chan->lc_proto->connecting)(chan->lc_upper);
187 		return 0;
188 	}
189 	if (err)
190 		goto fail;
191 
192 	/*
193 	 * We can queue a connect request now even though the link may
194 	 * not yet be open; Our mode setting is assured, and the queue
195 	 * will be started automatically at the right time.
196 	 */
197 	chan->lc_state = L2CAP_WAIT_RECV_CONNECT_RSP;
198 	err = l2cap_send_connect_req(chan);
199 	if (err)
200 		goto fail;
201 
202 	return 0;
203 
204 fail:
205 	chan->lc_state = L2CAP_CLOSED;
206 	hci_acl_close(chan->lc_link, err);
207 	chan->lc_link = NULL;
208 	return err;
209 }
210 
211 /*
212  * l2cap_peeraddr(l2cap_channel, sockaddr)
213  *
214  *	get remote address of channel
215  */
216 int
217 l2cap_peeraddr(struct l2cap_channel *chan, struct sockaddr_bt *addr)
218 {
219 
220 	memcpy(addr, &chan->lc_raddr, sizeof(struct sockaddr_bt));
221 	return 0;
222 }
223 
224 /*
225  * l2cap_disconnect(l2cap_channel, linger)
226  *
227  *	Initiate L2CAP disconnection. This corresponds to
228  *	"Close Channel Request" in the L2CAP specification
229  *	and will result in a call to
230  *
231  *		proto->disconnected(upper, error)
232  *
233  *	when the disconnection is complete. If linger is set,
234  *	the call will not be made until data has flushed from
235  *	the queue.
236  */
237 int
238 l2cap_disconnect(struct l2cap_channel *chan, int linger)
239 {
240 	int err = 0;
241 
242 	if (chan->lc_state == L2CAP_CLOSED
243 	    || chan->lc_state == L2CAP_WAIT_DISCONNECT)
244 		return EINVAL;
245 
246 	chan->lc_flags |= L2CAP_SHUTDOWN;
247 
248 	/*
249 	 * no need to do anything unless the queue is empty or
250 	 * we are not lingering..
251 	 */
252 	if ((MBUFQ_FIRST(&chan->lc_txq) == NULL && chan->lc_pending == 0)
253 	    || linger == 0) {
254 		chan->lc_state = L2CAP_WAIT_DISCONNECT;
255 		err = l2cap_send_disconnect_req(chan);
256 		if (err)
257 			l2cap_close(chan, err);
258 	}
259 	return err;
260 }
261 
262 /*
263  * l2cap_detach(handle)
264  *
265  *	Detach l2cap channel from handle & close it down
266  */
267 int
268 l2cap_detach(struct l2cap_channel **handle)
269 {
270 	struct l2cap_channel *chan;
271 
272 	chan = *handle;
273 	*handle = NULL;
274 
275 	if (chan->lc_state != L2CAP_CLOSED)
276 		l2cap_close(chan, 0);
277 
278 	if (chan->lc_lcid != L2CAP_NULL_CID) {
279 		LIST_REMOVE(chan, lc_ncid);
280 		chan->lc_lcid = L2CAP_NULL_CID;
281 	}
282 
283 	MBUFQ_DRAIN(&chan->lc_txq);
284 
285 	/*
286 	 * Could implement some kind of delayed expunge to make sure that the
287 	 * CID is really dead before it becomes available for reuse?
288 	 */
289 
290 	free(chan, M_BLUETOOTH);
291 	return 0;
292 }
293 
294 /*
295  * l2cap_listen(l2cap_channel)
296  *
297  *	Use this channel as a listening post (until detached). This will
298  *	result in calls to:
299  *
300  *		proto->newconn(upper, laddr, raddr)
301  *
302  *	for incoming connections matching the psm and local address of
303  *	the channel. NULL address is permitted and matches any device.
304  *	If L2CAP_PSM_ANY is bound the next higher unused value from the
305  *	dynamic range (above 0x1001) will be selected.
306  *
307  *	The upper layer should create and return a new channel.
308  *
309  *	You cannot use this channel for anything else subsequent to this call
310  */
311 int
312 l2cap_listen(struct l2cap_channel *chan)
313 {
314 	struct l2cap_channel *used, *prev = NULL;
315 	uint32_t psm;
316 
317 	if (chan->lc_lcid != L2CAP_NULL_CID)
318 		return EINVAL;
319 
320 	/*
321 	 * This is simplistic but its not really worth spending a
322 	 * lot of time looking for an unused PSM..
323 	 */
324 	if (chan->lc_laddr.bt_psm == L2CAP_PSM_ANY) {
325 		psm = 0x1001;
326 		used = LIST_FIRST(&l2cap_listen_list);
327 
328 		if (used != NULL && used->lc_laddr.bt_psm >= psm) {
329 			psm = used->lc_laddr.bt_psm + 0x0002;
330 			if ((psm & 0x0100) != 0)
331 				psm += 0x0100;
332 
333 			if (psm > UINT16_MAX)
334 				return EADDRNOTAVAIL;
335 		}
336 
337 		chan->lc_laddr.bt_psm = psm;
338 	} else if (L2CAP_PSM_INVALID(chan->lc_laddr.bt_psm))
339 		return EINVAL;
340 
341 	/*
342 	 * This CID is irrelevant, as the channel is not stored on the active
343 	 * list and the socket code does not allow operations on listening
344 	 * sockets, but we set it so the detach code knows to LIST_REMOVE the
345 	 * channel.
346 	 */
347 	chan->lc_lcid = L2CAP_SIGNAL_CID;
348 
349 	/*
350 	 * The list of listening channels is stored in an order such that new
351 	 * listeners dont usurp current listeners, but that specific listening
352 	 * takes precedence over promiscuous, and the connect request code can
353 	 * easily use the first matching entry.
354 	 */
355 	LIST_FOREACH(used, &l2cap_listen_list, lc_ncid) {
356 		if (used->lc_laddr.bt_psm < chan->lc_laddr.bt_psm)
357 			break;
358 
359 		if (used->lc_laddr.bt_psm == chan->lc_laddr.bt_psm
360 			&& bdaddr_any(&used->lc_laddr.bt_bdaddr)
361 			&& !bdaddr_any(&chan->lc_laddr.bt_bdaddr))
362 			break;
363 
364 		prev = used;
365 	}
366 
367 	if (prev == NULL)
368 		LIST_INSERT_HEAD(&l2cap_listen_list, chan, lc_ncid);
369 	else
370 		LIST_INSERT_AFTER(prev, chan, lc_ncid);
371 
372 	return 0;
373 }
374 
375 /*
376  * l2cap_send(l2cap_channel, mbuf)
377  *
378  *	Output SDU on channel described by channel. This corresponds
379  *	to "Send Data Request" in the L2CAP specification. The upper
380  *	layer will be notified when SDU's have completed sending by a
381  *	call to:
382  *
383  *		proto->complete(upper, n)
384  *
385  *	(currently n == 1)
386  *
387  *	Note: I'm not sure how this will work out, but I think that
388  *	if outgoing Retransmission Mode or Flow Control Mode is
389  *	negotiated then this call will not be made until the SDU has
390  *	been acknowleged by the peer L2CAP entity. For 'Best Effort'
391  *	it will be made when the packet has cleared the controller
392  *	buffers.
393  *
394  *	We only support Basic mode so far, so encapsulate with a
395  *	B-Frame header and start sending if we are not already
396  */
397 int
398 l2cap_send(struct l2cap_channel *chan, struct mbuf *m)
399 {
400 	l2cap_hdr_t *hdr;
401 	int plen;
402 
403 	if (chan->lc_state == L2CAP_CLOSED) {
404 		m_freem(m);
405 		return ENOTCONN;
406 	}
407 
408 	plen = m->m_pkthdr.len;
409 
410 	DPRINTFN(5, "send %d bytes on CID #%d (pending = %d)\n",
411 		plen, chan->lc_lcid, chan->lc_pending);
412 
413 	/* Encapsulate with B-Frame */
414 	M_PREPEND(m, sizeof(l2cap_hdr_t), M_DONTWAIT);
415 	if (m == NULL)
416 		return ENOMEM;
417 
418 	hdr = mtod(m, l2cap_hdr_t *);
419 	hdr->length = htole16(plen);
420 	hdr->dcid = htole16(chan->lc_rcid);
421 
422 	/* Queue it on our list */
423 	MBUFQ_ENQUEUE(&chan->lc_txq, m);
424 
425 	/* If we are not sending, then start doing so */
426 	if (chan->lc_pending == 0)
427 		return l2cap_start(chan);
428 
429 	return 0;
430 }
431 
432 /*
433  * l2cap_setopt(l2cap_channel, sopt)
434  *
435  *	Apply configuration options to channel. This corresponds to
436  *	"Configure Channel Request" in the L2CAP specification.
437  *
438  *	for SO_L2CAP_LM, the settings will take effect when the
439  *	channel is established. If the channel is already open,
440  *	a call to
441  *		proto->linkmode(upper, new)
442  *
443  *	will be made when the change is complete.
444  */
445 int
446 l2cap_setopt(struct l2cap_channel *chan, const struct sockopt *sopt)
447 {
448 	int mode, err = 0;
449 	uint16_t mtu;
450 
451 	switch (sopt->sopt_name) {
452 	case SO_L2CAP_IMTU:	/* set Incoming MTU */
453 		err = sockopt_get(sopt, &mtu, sizeof(mtu));
454 		if (err)
455 			break;
456 
457 		if (mtu < L2CAP_MTU_MINIMUM)
458 			err = EINVAL;
459 		else if (chan->lc_state == L2CAP_CLOSED)
460 			chan->lc_imtu = mtu;
461 		else
462 			err = EBUSY;
463 
464 		break;
465 
466 	case SO_L2CAP_LM:	/* set link mode */
467 		err = sockopt_getint(sopt, &mode);
468 		if (err)
469 			break;
470 
471 		mode &= (L2CAP_LM_SECURE | L2CAP_LM_ENCRYPT | L2CAP_LM_AUTH);
472 
473 		if (mode & L2CAP_LM_SECURE)
474 			mode |= L2CAP_LM_ENCRYPT;
475 
476 		if (mode & L2CAP_LM_ENCRYPT)
477 			mode |= L2CAP_LM_AUTH;
478 
479 		chan->lc_mode = mode;
480 
481 		if (chan->lc_state == L2CAP_OPEN)
482 			err = l2cap_setmode(chan);
483 
484 		break;
485 
486 	case SO_L2CAP_OQOS:	/* set Outgoing QoS flow spec */
487 	case SO_L2CAP_FLUSH:	/* set Outgoing Flush Timeout */
488 	default:
489 		err = ENOPROTOOPT;
490 		break;
491 	}
492 
493 	return err;
494 }
495 
496 /*
497  * l2cap_getopt(l2cap_channel, sopt)
498  *
499  *	Return configuration parameters.
500  */
501 int
502 l2cap_getopt(struct l2cap_channel *chan, struct sockopt *sopt)
503 {
504 
505 	switch (sopt->sopt_name) {
506 	case SO_L2CAP_IMTU:	/* get Incoming MTU */
507 		return sockopt_set(sopt, &chan->lc_imtu, sizeof(uint16_t));
508 
509 	case SO_L2CAP_OMTU:	/* get Outgoing MTU */
510 		return sockopt_set(sopt, &chan->lc_omtu, sizeof(uint16_t));
511 
512 	case SO_L2CAP_IQOS:	/* get Incoming QoS flow spec */
513 		return sockopt_set(sopt, &chan->lc_iqos, sizeof(l2cap_qos_t));
514 
515 	case SO_L2CAP_OQOS:	/* get Outgoing QoS flow spec */
516 		return sockopt_set(sopt, &chan->lc_oqos, sizeof(l2cap_qos_t));
517 
518 	case SO_L2CAP_FLUSH:	/* get Flush Timeout */
519 		return sockopt_set(sopt, &chan->lc_flush, sizeof(uint16_t));
520 
521 	case SO_L2CAP_LM:	/* get link mode */
522 		return sockopt_setint(sopt, chan->lc_mode);
523 
524 	default:
525 		break;
526 	}
527 
528 	return ENOPROTOOPT;
529 }
530