xref: /linux/net/bluetooth/bnep/core.c (revision eb2bce7f5e7ac1ca6da434461217fadf3c688d2c) 
1 /*
2    BNEP implementation for Linux Bluetooth stack (BlueZ).
3    Copyright (C) 2001-2002 Inventel Systemes
4    Written 2001-2002 by
5 	Cl�ment Moreau <clement.moreau@inventel.fr>
6 	David Libault  <david.libault@inventel.fr>
7 
8    Copyright (C) 2002 Maxim Krasnyansky <maxk@qualcomm.com>
9 
10    This program is free software; you can redistribute it and/or modify
11    it under the terms of the GNU General Public License version 2 as
12    published by the Free Software Foundation;
13 
14    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
15    OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
17    IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY
18    CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES
19    WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
20    ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
21    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
22 
23    ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS,
24    COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS
25    SOFTWARE IS DISCLAIMED.
26 */
27 
28 /*
29  * $Id: core.c,v 1.20 2002/08/04 21:23:58 maxk Exp $
30  */
31 
32 #include <linux/module.h>
33 
34 #include <linux/kernel.h>
35 #include <linux/sched.h>
36 #include <linux/signal.h>
37 #include <linux/init.h>
38 #include <linux/wait.h>
39 #include <linux/errno.h>
40 #include <linux/smp_lock.h>
41 #include <linux/net.h>
42 #include <net/sock.h>
43 
44 #include <linux/socket.h>
45 #include <linux/file.h>
46 
47 #include <linux/netdevice.h>
48 #include <linux/etherdevice.h>
49 #include <linux/skbuff.h>
50 
51 #include <asm/unaligned.h>
52 
53 #include <net/bluetooth/bluetooth.h>
54 #include <net/bluetooth/hci_core.h>
55 #include <net/bluetooth/l2cap.h>
56 
57 #include "bnep.h"
58 
59 #ifndef CONFIG_BT_BNEP_DEBUG
60 #undef  BT_DBG
61 #define BT_DBG(D...)
62 #endif
63 
64 #define VERSION "1.2"
65 
66 static LIST_HEAD(bnep_session_list);
67 static DECLARE_RWSEM(bnep_session_sem);
68 
69 static struct bnep_session *__bnep_get_session(u8 *dst)
70 {
71 	struct bnep_session *s;
72 	struct list_head *p;
73 
74 	BT_DBG("");
75 
76 	list_for_each(p, &bnep_session_list) {
77 		s = list_entry(p, struct bnep_session, list);
78 		if (!compare_ether_addr(dst, s->eh.h_source))
79 			return s;
80 	}
81 	return NULL;
82 }
83 
84 static void __bnep_link_session(struct bnep_session *s)
85 {
86 	/* It's safe to call __module_get() here because sessions are added
87 	   by the socket layer which has to hold the refference to this module.
88 	 */
89 	__module_get(THIS_MODULE);
90 	list_add(&s->list, &bnep_session_list);
91 }
92 
93 static void __bnep_unlink_session(struct bnep_session *s)
94 {
95 	list_del(&s->list);
96 	module_put(THIS_MODULE);
97 }
98 
99 static int bnep_send(struct bnep_session *s, void *data, size_t len)
100 {
101 	struct socket *sock = s->sock;
102 	struct kvec iv = { data, len };
103 
104 	return kernel_sendmsg(sock, &s->msg, &iv, 1, len);
105 }
106 
107 static int bnep_send_rsp(struct bnep_session *s, u8 ctrl, u16 resp)
108 {
109 	struct bnep_control_rsp rsp;
110 	rsp.type = BNEP_CONTROL;
111 	rsp.ctrl = ctrl;
112 	rsp.resp = htons(resp);
113 	return bnep_send(s, &rsp, sizeof(rsp));
114 }
115 
116 #ifdef CONFIG_BT_BNEP_PROTO_FILTER
117 static inline void bnep_set_default_proto_filter(struct bnep_session *s)
118 {
119 	/* (IPv4, ARP)  */
120 	s->proto_filter[0].start = ETH_P_IP;
121 	s->proto_filter[0].end   = ETH_P_ARP;
122 	/* (RARP, AppleTalk) */
123 	s->proto_filter[1].start = ETH_P_RARP;
124 	s->proto_filter[1].end   = ETH_P_AARP;
125 	/* (IPX, IPv6) */
126 	s->proto_filter[2].start = ETH_P_IPX;
127 	s->proto_filter[2].end   = ETH_P_IPV6;
128 }
129 #endif
130 
131 static int bnep_ctrl_set_netfilter(struct bnep_session *s, __be16 *data, int len)
132 {
133 	int n;
134 
135 	if (len < 2)
136 		return -EILSEQ;
137 
138 	n = ntohs(get_unaligned(data));
139 	data++; len -= 2;
140 
141 	if (len < n)
142 		return -EILSEQ;
143 
144 	BT_DBG("filter len %d", n);
145 
146 #ifdef CONFIG_BT_BNEP_PROTO_FILTER
147 	n /= 4;
148 	if (n <= BNEP_MAX_PROTO_FILTERS) {
149 		struct bnep_proto_filter *f = s->proto_filter;
150 		int i;
151 
152 		for (i = 0; i < n; i++) {
153 			f[i].start = ntohs(get_unaligned(data++));
154 			f[i].end   = ntohs(get_unaligned(data++));
155 
156 			BT_DBG("proto filter start %d end %d",
157 				f[i].start, f[i].end);
158 		}
159 
160 		if (i < BNEP_MAX_PROTO_FILTERS)
161 			memset(f + i, 0, sizeof(*f));
162 
163 		if (n == 0)
164 			bnep_set_default_proto_filter(s);
165 
166 		bnep_send_rsp(s, BNEP_FILTER_NET_TYPE_RSP, BNEP_SUCCESS);
167 	} else {
168 		bnep_send_rsp(s, BNEP_FILTER_NET_TYPE_RSP, BNEP_FILTER_LIMIT_REACHED);
169 	}
170 #else
171 	bnep_send_rsp(s, BNEP_FILTER_NET_TYPE_RSP, BNEP_FILTER_UNSUPPORTED_REQ);
172 #endif
173 	return 0;
174 }
175 
176 static int bnep_ctrl_set_mcfilter(struct bnep_session *s, u8 *data, int len)
177 {
178 	int n;
179 
180 	if (len < 2)
181 		return -EILSEQ;
182 
183 	n = ntohs(get_unaligned((__be16 *) data));
184 	data += 2; len -= 2;
185 
186 	if (len < n)
187 		return -EILSEQ;
188 
189 	BT_DBG("filter len %d", n);
190 
191 #ifdef CONFIG_BT_BNEP_MC_FILTER
192 	n /= (ETH_ALEN * 2);
193 
194 	if (n > 0) {
195 		s->mc_filter = 0;
196 
197 		/* Always send broadcast */
198 		set_bit(bnep_mc_hash(s->dev->broadcast), (ulong *) &s->mc_filter);
199 
200 		/* Add address ranges to the multicast hash */
201 		for (; n > 0; n--) {
202 			u8 a1[6], *a2;
203 
204 			memcpy(a1, data, ETH_ALEN); data += ETH_ALEN;
205 			a2 = data; data += ETH_ALEN;
206 
207 			BT_DBG("mc filter %s -> %s",
208 				batostr((void *) a1), batostr((void *) a2));
209 
210 			#define INCA(a) { int i = 5; while (i >=0 && ++a[i--] == 0); }
211 
212 			/* Iterate from a1 to a2 */
213 			set_bit(bnep_mc_hash(a1), (ulong *) &s->mc_filter);
214 			while (memcmp(a1, a2, 6) < 0 && s->mc_filter != ~0LL) {
215 				INCA(a1);
216 				set_bit(bnep_mc_hash(a1), (ulong *) &s->mc_filter);
217 			}
218 		}
219 	}
220 
221 	BT_DBG("mc filter hash 0x%llx", s->mc_filter);
222 
223 	bnep_send_rsp(s, BNEP_FILTER_MULTI_ADDR_RSP, BNEP_SUCCESS);
224 #else
225 	bnep_send_rsp(s, BNEP_FILTER_MULTI_ADDR_RSP, BNEP_FILTER_UNSUPPORTED_REQ);
226 #endif
227 	return 0;
228 }
229 
230 static int bnep_rx_control(struct bnep_session *s, void *data, int len)
231 {
232 	u8  cmd = *(u8 *)data;
233 	int err = 0;
234 
235 	data++; len--;
236 
237 	switch (cmd) {
238 	case BNEP_CMD_NOT_UNDERSTOOD:
239 	case BNEP_SETUP_CONN_REQ:
240 	case BNEP_SETUP_CONN_RSP:
241 	case BNEP_FILTER_NET_TYPE_RSP:
242 	case BNEP_FILTER_MULTI_ADDR_RSP:
243 		/* Ignore these for now */
244 		break;
245 
246 	case BNEP_FILTER_NET_TYPE_SET:
247 		err = bnep_ctrl_set_netfilter(s, data, len);
248 		break;
249 
250 	case BNEP_FILTER_MULTI_ADDR_SET:
251 		err = bnep_ctrl_set_mcfilter(s, data, len);
252 		break;
253 
254 	default: {
255 			u8 pkt[3];
256 			pkt[0] = BNEP_CONTROL;
257 			pkt[1] = BNEP_CMD_NOT_UNDERSTOOD;
258 			pkt[2] = cmd;
259 			bnep_send(s, pkt, sizeof(pkt));
260 		}
261 		break;
262 	}
263 
264 	return err;
265 }
266 
267 static int bnep_rx_extension(struct bnep_session *s, struct sk_buff *skb)
268 {
269 	struct bnep_ext_hdr *h;
270 	int err = 0;
271 
272 	do {
273 		h = (void *) skb->data;
274 		if (!skb_pull(skb, sizeof(*h))) {
275 			err = -EILSEQ;
276 			break;
277 		}
278 
279 		BT_DBG("type 0x%x len %d", h->type, h->len);
280 
281 		switch (h->type & BNEP_TYPE_MASK) {
282 		case BNEP_EXT_CONTROL:
283 			bnep_rx_control(s, skb->data, skb->len);
284 			break;
285 
286 		default:
287 			/* Unknown extension, skip it. */
288 			break;
289 		}
290 
291 		if (!skb_pull(skb, h->len)) {
292 			err = -EILSEQ;
293 			break;
294 		}
295 	} while (!err && (h->type & BNEP_EXT_HEADER));
296 
297 	return err;
298 }
299 
300 static u8 __bnep_rx_hlen[] = {
301 	ETH_HLEN,     /* BNEP_GENERAL */
302 	0,            /* BNEP_CONTROL */
303 	2,            /* BNEP_COMPRESSED */
304 	ETH_ALEN + 2, /* BNEP_COMPRESSED_SRC_ONLY */
305 	ETH_ALEN + 2  /* BNEP_COMPRESSED_DST_ONLY */
306 };
307 #define BNEP_RX_TYPES	(sizeof(__bnep_rx_hlen) - 1)
308 
309 static inline int bnep_rx_frame(struct bnep_session *s, struct sk_buff *skb)
310 {
311 	struct net_device *dev = s->dev;
312 	struct sk_buff *nskb;
313 	u8 type;
314 
315 	dev->last_rx = jiffies;
316 	s->stats.rx_bytes += skb->len;
317 
318 	type = *(u8 *) skb->data; skb_pull(skb, 1);
319 
320 	if ((type & BNEP_TYPE_MASK) > BNEP_RX_TYPES)
321 		goto badframe;
322 
323 	if ((type & BNEP_TYPE_MASK) == BNEP_CONTROL) {
324 		bnep_rx_control(s, skb->data, skb->len);
325 		kfree_skb(skb);
326 		return 0;
327 	}
328 
329 	skb_reset_mac_header(skb);
330 
331 	/* Verify and pull out header */
332 	if (!skb_pull(skb, __bnep_rx_hlen[type & BNEP_TYPE_MASK]))
333 		goto badframe;
334 
335 	s->eh.h_proto = get_unaligned((__be16 *) (skb->data - 2));
336 
337 	if (type & BNEP_EXT_HEADER) {
338 		if (bnep_rx_extension(s, skb) < 0)
339 			goto badframe;
340 	}
341 
342 	/* Strip 802.1p header */
343 	if (ntohs(s->eh.h_proto) == 0x8100) {
344 		if (!skb_pull(skb, 4))
345 			goto badframe;
346 		s->eh.h_proto = get_unaligned((__be16 *) (skb->data - 2));
347 	}
348 
349 	/* We have to alloc new skb and copy data here :(. Because original skb
350 	 * may not be modified and because of the alignment requirements. */
351 	nskb = alloc_skb(2 + ETH_HLEN + skb->len, GFP_KERNEL);
352 	if (!nskb) {
353 		s->stats.rx_dropped++;
354 		kfree_skb(skb);
355 		return -ENOMEM;
356 	}
357 	skb_reserve(nskb, 2);
358 
359 	/* Decompress header and construct ether frame */
360 	switch (type & BNEP_TYPE_MASK) {
361 	case BNEP_COMPRESSED:
362 		memcpy(__skb_put(nskb, ETH_HLEN), &s->eh, ETH_HLEN);
363 		break;
364 
365 	case BNEP_COMPRESSED_SRC_ONLY:
366 		memcpy(__skb_put(nskb, ETH_ALEN), s->eh.h_dest, ETH_ALEN);
367 		memcpy(__skb_put(nskb, ETH_ALEN), skb_mac_header(skb), ETH_ALEN);
368 		put_unaligned(s->eh.h_proto, (__be16 *) __skb_put(nskb, 2));
369 		break;
370 
371 	case BNEP_COMPRESSED_DST_ONLY:
372 		memcpy(__skb_put(nskb, ETH_ALEN), skb_mac_header(skb),
373 		       ETH_ALEN);
374 		memcpy(__skb_put(nskb, ETH_ALEN + 2), s->eh.h_source,
375 		       ETH_ALEN + 2);
376 		break;
377 
378 	case BNEP_GENERAL:
379 		memcpy(__skb_put(nskb, ETH_ALEN * 2), skb_mac_header(skb),
380 		       ETH_ALEN * 2);
381 		put_unaligned(s->eh.h_proto, (__be16 *) __skb_put(nskb, 2));
382 		break;
383 	}
384 
385 	skb_copy_from_linear_data(skb, __skb_put(nskb, skb->len), skb->len);
386 	kfree_skb(skb);
387 
388 	s->stats.rx_packets++;
389 	nskb->ip_summed = CHECKSUM_NONE;
390 	nskb->protocol  = eth_type_trans(nskb, dev);
391 	netif_rx_ni(nskb);
392 	return 0;
393 
394 badframe:
395 	s->stats.rx_errors++;
396 	kfree_skb(skb);
397 	return 0;
398 }
399 
400 static u8 __bnep_tx_types[] = {
401 	BNEP_GENERAL,
402 	BNEP_COMPRESSED_SRC_ONLY,
403 	BNEP_COMPRESSED_DST_ONLY,
404 	BNEP_COMPRESSED
405 };
406 
407 static inline int bnep_tx_frame(struct bnep_session *s, struct sk_buff *skb)
408 {
409 	struct ethhdr *eh = (void *) skb->data;
410 	struct socket *sock = s->sock;
411 	struct kvec iv[3];
412 	int len = 0, il = 0;
413 	u8 type = 0;
414 
415 	BT_DBG("skb %p dev %p type %d", skb, skb->dev, skb->pkt_type);
416 
417 	if (!skb->dev) {
418 		/* Control frame sent by us */
419 		goto send;
420 	}
421 
422 	iv[il++] = (struct kvec) { &type, 1 };
423 	len++;
424 
425 	if (!compare_ether_addr(eh->h_dest, s->eh.h_source))
426 		type |= 0x01;
427 
428 	if (!compare_ether_addr(eh->h_source, s->eh.h_dest))
429 		type |= 0x02;
430 
431 	if (type)
432 		skb_pull(skb, ETH_ALEN * 2);
433 
434 	type = __bnep_tx_types[type];
435 	switch (type) {
436 	case BNEP_COMPRESSED_SRC_ONLY:
437 		iv[il++] = (struct kvec) { eh->h_source, ETH_ALEN };
438 		len += ETH_ALEN;
439 		break;
440 
441 	case BNEP_COMPRESSED_DST_ONLY:
442 		iv[il++] = (struct kvec) { eh->h_dest, ETH_ALEN };
443 		len += ETH_ALEN;
444 		break;
445 	}
446 
447 send:
448 	iv[il++] = (struct kvec) { skb->data, skb->len };
449 	len += skb->len;
450 
451 	/* FIXME: linearize skb */
452 	{
453 		len = kernel_sendmsg(sock, &s->msg, iv, il, len);
454 	}
455 	kfree_skb(skb);
456 
457 	if (len > 0) {
458 		s->stats.tx_bytes += len;
459 		s->stats.tx_packets++;
460 		return 0;
461 	}
462 
463 	return len;
464 }
465 
466 static int bnep_session(void *arg)
467 {
468 	struct bnep_session *s = arg;
469 	struct net_device *dev = s->dev;
470 	struct sock *sk = s->sock->sk;
471 	struct sk_buff *skb;
472 	wait_queue_t wait;
473 
474 	BT_DBG("");
475 
476 	daemonize("kbnepd %s", dev->name);
477 	set_user_nice(current, -15);
478 	current->flags |= PF_NOFREEZE;
479 
480 	init_waitqueue_entry(&wait, current);
481 	add_wait_queue(sk->sk_sleep, &wait);
482 	while (!atomic_read(&s->killed)) {
483 		set_current_state(TASK_INTERRUPTIBLE);
484 
485 		// RX
486 		while ((skb = skb_dequeue(&sk->sk_receive_queue))) {
487 			skb_orphan(skb);
488 			bnep_rx_frame(s, skb);
489 		}
490 
491 		if (sk->sk_state != BT_CONNECTED)
492 			break;
493 
494 		// TX
495 		while ((skb = skb_dequeue(&sk->sk_write_queue)))
496 			if (bnep_tx_frame(s, skb))
497 				break;
498 		netif_wake_queue(dev);
499 
500 		schedule();
501 	}
502 	set_current_state(TASK_RUNNING);
503 	remove_wait_queue(sk->sk_sleep, &wait);
504 
505 	/* Cleanup session */
506 	down_write(&bnep_session_sem);
507 
508 	/* Delete network device */
509 	unregister_netdev(dev);
510 
511 	/* Release the socket */
512 	fput(s->sock->file);
513 
514 	__bnep_unlink_session(s);
515 
516 	up_write(&bnep_session_sem);
517 	free_netdev(dev);
518 	return 0;
519 }
520 
521 static struct device *bnep_get_device(struct bnep_session *session)
522 {
523 	bdaddr_t *src = &bt_sk(session->sock->sk)->src;
524 	bdaddr_t *dst = &bt_sk(session->sock->sk)->dst;
525 	struct hci_dev *hdev;
526 	struct hci_conn *conn;
527 
528 	hdev = hci_get_route(dst, src);
529 	if (!hdev)
530 		return NULL;
531 
532 	conn = hci_conn_hash_lookup_ba(hdev, ACL_LINK, dst);
533 
534 	hci_dev_put(hdev);
535 
536 	return conn ? &conn->dev : NULL;
537 }
538 
539 int bnep_add_connection(struct bnep_connadd_req *req, struct socket *sock)
540 {
541 	struct net_device *dev;
542 	struct bnep_session *s, *ss;
543 	u8 dst[ETH_ALEN], src[ETH_ALEN];
544 	int err;
545 
546 	BT_DBG("");
547 
548 	baswap((void *) dst, &bt_sk(sock->sk)->dst);
549 	baswap((void *) src, &bt_sk(sock->sk)->src);
550 
551 	/* session struct allocated as private part of net_device */
552 	dev = alloc_netdev(sizeof(struct bnep_session),
553 			   (*req->device) ? req->device : "bnep%d",
554 			   bnep_net_setup);
555 	if (!dev)
556 		return -ENOMEM;
557 
558 	down_write(&bnep_session_sem);
559 
560 	ss = __bnep_get_session(dst);
561 	if (ss && ss->state == BT_CONNECTED) {
562 		err = -EEXIST;
563 		goto failed;
564 	}
565 
566 	s = dev->priv;
567 
568 	/* This is rx header therefore addresses are swapped.
569 	 * ie eh.h_dest is our local address. */
570 	memcpy(s->eh.h_dest,   &src, ETH_ALEN);
571 	memcpy(s->eh.h_source, &dst, ETH_ALEN);
572 	memcpy(dev->dev_addr, s->eh.h_dest, ETH_ALEN);
573 
574 	s->dev   = dev;
575 	s->sock  = sock;
576 	s->role  = req->role;
577 	s->state = BT_CONNECTED;
578 
579 	s->msg.msg_flags = MSG_NOSIGNAL;
580 
581 #ifdef CONFIG_BT_BNEP_MC_FILTER
582 	/* Set default mc filter */
583 	set_bit(bnep_mc_hash(dev->broadcast), (ulong *) &s->mc_filter);
584 #endif
585 
586 #ifdef CONFIG_BT_BNEP_PROTO_FILTER
587 	/* Set default protocol filter */
588 	bnep_set_default_proto_filter(s);
589 #endif
590 
591 	SET_NETDEV_DEV(dev, bnep_get_device(s));
592 
593 	err = register_netdev(dev);
594 	if (err) {
595 		goto failed;
596 	}
597 
598 	__bnep_link_session(s);
599 
600 	err = kernel_thread(bnep_session, s, CLONE_KERNEL);
601 	if (err < 0) {
602 		/* Session thread start failed, gotta cleanup. */
603 		unregister_netdev(dev);
604 		__bnep_unlink_session(s);
605 		goto failed;
606 	}
607 
608 	up_write(&bnep_session_sem);
609 	strcpy(req->device, dev->name);
610 	return 0;
611 
612 failed:
613 	up_write(&bnep_session_sem);
614 	free_netdev(dev);
615 	return err;
616 }
617 
618 int bnep_del_connection(struct bnep_conndel_req *req)
619 {
620 	struct bnep_session *s;
621 	int  err = 0;
622 
623 	BT_DBG("");
624 
625 	down_read(&bnep_session_sem);
626 
627 	s = __bnep_get_session(req->dst);
628 	if (s) {
629 		/* Wakeup user-space which is polling for socket errors.
630 		 * This is temporary hack untill we have shutdown in L2CAP */
631 		s->sock->sk->sk_err = EUNATCH;
632 
633 		/* Kill session thread */
634 		atomic_inc(&s->killed);
635 		wake_up_interruptible(s->sock->sk->sk_sleep);
636 	} else
637 		err = -ENOENT;
638 
639 	up_read(&bnep_session_sem);
640 	return err;
641 }
642 
643 static void __bnep_copy_ci(struct bnep_conninfo *ci, struct bnep_session *s)
644 {
645 	memcpy(ci->dst, s->eh.h_source, ETH_ALEN);
646 	strcpy(ci->device, s->dev->name);
647 	ci->flags = s->flags;
648 	ci->state = s->state;
649 	ci->role  = s->role;
650 }
651 
652 int bnep_get_connlist(struct bnep_connlist_req *req)
653 {
654 	struct list_head *p;
655 	int err = 0, n = 0;
656 
657 	down_read(&bnep_session_sem);
658 
659 	list_for_each(p, &bnep_session_list) {
660 		struct bnep_session *s;
661 		struct bnep_conninfo ci;
662 
663 		s = list_entry(p, struct bnep_session, list);
664 
665 		__bnep_copy_ci(&ci, s);
666 
667 		if (copy_to_user(req->ci, &ci, sizeof(ci))) {
668 			err = -EFAULT;
669 			break;
670 		}
671 
672 		if (++n >= req->cnum)
673 			break;
674 
675 		req->ci++;
676 	}
677 	req->cnum = n;
678 
679 	up_read(&bnep_session_sem);
680 	return err;
681 }
682 
683 int bnep_get_conninfo(struct bnep_conninfo *ci)
684 {
685 	struct bnep_session *s;
686 	int err = 0;
687 
688 	down_read(&bnep_session_sem);
689 
690 	s = __bnep_get_session(ci->dst);
691 	if (s)
692 		__bnep_copy_ci(ci, s);
693 	else
694 		err = -ENOENT;
695 
696 	up_read(&bnep_session_sem);
697 	return err;
698 }
699 
700 static int __init bnep_init(void)
701 {
702 	char flt[50] = "";
703 
704 	l2cap_load();
705 
706 #ifdef CONFIG_BT_BNEP_PROTO_FILTER
707 	strcat(flt, "protocol ");
708 #endif
709 
710 #ifdef CONFIG_BT_BNEP_MC_FILTER
711 	strcat(flt, "multicast");
712 #endif
713 
714 	BT_INFO("BNEP (Ethernet Emulation) ver %s", VERSION);
715 	if (flt[0])
716 		BT_INFO("BNEP filters: %s", flt);
717 
718 	bnep_sock_init();
719 	return 0;
720 }
721 
722 static void __exit bnep_exit(void)
723 {
724 	bnep_sock_cleanup();
725 }
726 
727 module_init(bnep_init);
728 module_exit(bnep_exit);
729 
730 MODULE_AUTHOR("David Libault <david.libault@inventel.fr>, Maxim Krasnyansky <maxk@qualcomm.com>");
731 MODULE_DESCRIPTION("Bluetooth BNEP ver " VERSION);
732 MODULE_VERSION(VERSION);
733 MODULE_LICENSE("GPL");
734 MODULE_ALIAS("bt-proto-4");
735