xref: /linux/net/bluetooth/bnep/core.c (revision c537b994505099b7197e7d3125b942ecbcc51eb6) 
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->mac.raw = skb->data;
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.raw, 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.raw, ETH_ALEN);
373 		memcpy(__skb_put(nskb, ETH_ALEN + 2), s->eh.h_source, ETH_ALEN + 2);
374 		break;
375 
376 	case BNEP_GENERAL:
377 		memcpy(__skb_put(nskb, ETH_ALEN * 2), skb->mac.raw, ETH_ALEN * 2);
378 		put_unaligned(s->eh.h_proto, (__be16 *) __skb_put(nskb, 2));
379 		break;
380 	}
381 
382 	memcpy(__skb_put(nskb, skb->len), skb->data, skb->len);
383 	kfree_skb(skb);
384 
385 	s->stats.rx_packets++;
386 	nskb->dev       = dev;
387 	nskb->ip_summed = CHECKSUM_NONE;
388 	nskb->protocol  = eth_type_trans(nskb, dev);
389 	netif_rx_ni(nskb);
390 	return 0;
391 
392 badframe:
393 	s->stats.rx_errors++;
394 	kfree_skb(skb);
395 	return 0;
396 }
397 
398 static u8 __bnep_tx_types[] = {
399 	BNEP_GENERAL,
400 	BNEP_COMPRESSED_SRC_ONLY,
401 	BNEP_COMPRESSED_DST_ONLY,
402 	BNEP_COMPRESSED
403 };
404 
405 static inline int bnep_tx_frame(struct bnep_session *s, struct sk_buff *skb)
406 {
407 	struct ethhdr *eh = (void *) skb->data;
408 	struct socket *sock = s->sock;
409 	struct kvec iv[3];
410 	int len = 0, il = 0;
411 	u8 type = 0;
412 
413 	BT_DBG("skb %p dev %p type %d", skb, skb->dev, skb->pkt_type);
414 
415 	if (!skb->dev) {
416 		/* Control frame sent by us */
417 		goto send;
418 	}
419 
420 	iv[il++] = (struct kvec) { &type, 1 };
421 	len++;
422 
423 	if (!compare_ether_addr(eh->h_dest, s->eh.h_source))
424 		type |= 0x01;
425 
426 	if (!compare_ether_addr(eh->h_source, s->eh.h_dest))
427 		type |= 0x02;
428 
429 	if (type)
430 		skb_pull(skb, ETH_ALEN * 2);
431 
432 	type = __bnep_tx_types[type];
433 	switch (type) {
434 	case BNEP_COMPRESSED_SRC_ONLY:
435 		iv[il++] = (struct kvec) { eh->h_source, ETH_ALEN };
436 		len += ETH_ALEN;
437 		break;
438 
439 	case BNEP_COMPRESSED_DST_ONLY:
440 		iv[il++] = (struct kvec) { eh->h_dest, ETH_ALEN };
441 		len += ETH_ALEN;
442 		break;
443 	}
444 
445 send:
446 	iv[il++] = (struct kvec) { skb->data, skb->len };
447 	len += skb->len;
448 
449 	/* FIXME: linearize skb */
450 	{
451 		len = kernel_sendmsg(sock, &s->msg, iv, il, len);
452 	}
453 	kfree_skb(skb);
454 
455 	if (len > 0) {
456 		s->stats.tx_bytes += len;
457 		s->stats.tx_packets++;
458 		return 0;
459 	}
460 
461 	return len;
462 }
463 
464 static int bnep_session(void *arg)
465 {
466 	struct bnep_session *s = arg;
467 	struct net_device *dev = s->dev;
468 	struct sock *sk = s->sock->sk;
469 	struct sk_buff *skb;
470 	wait_queue_t wait;
471 
472 	BT_DBG("");
473 
474 	daemonize("kbnepd %s", dev->name);
475 	set_user_nice(current, -15);
476 	current->flags |= PF_NOFREEZE;
477 
478 	init_waitqueue_entry(&wait, current);
479 	add_wait_queue(sk->sk_sleep, &wait);
480 	while (!atomic_read(&s->killed)) {
481 		set_current_state(TASK_INTERRUPTIBLE);
482 
483 		// RX
484 		while ((skb = skb_dequeue(&sk->sk_receive_queue))) {
485 			skb_orphan(skb);
486 			bnep_rx_frame(s, skb);
487 		}
488 
489 		if (sk->sk_state != BT_CONNECTED)
490 			break;
491 
492 		// TX
493 		while ((skb = skb_dequeue(&sk->sk_write_queue)))
494 			if (bnep_tx_frame(s, skb))
495 				break;
496 		netif_wake_queue(dev);
497 
498 		schedule();
499 	}
500 	set_current_state(TASK_RUNNING);
501 	remove_wait_queue(sk->sk_sleep, &wait);
502 
503 	/* Cleanup session */
504 	down_write(&bnep_session_sem);
505 
506 	/* Delete network device */
507 	unregister_netdev(dev);
508 
509 	/* Release the socket */
510 	fput(s->sock->file);
511 
512 	__bnep_unlink_session(s);
513 
514 	up_write(&bnep_session_sem);
515 	free_netdev(dev);
516 	return 0;
517 }
518 
519 static struct device *bnep_get_device(struct bnep_session *session)
520 {
521 	bdaddr_t *src = &bt_sk(session->sock->sk)->src;
522 	bdaddr_t *dst = &bt_sk(session->sock->sk)->dst;
523 	struct hci_dev *hdev;
524 	struct hci_conn *conn;
525 
526 	hdev = hci_get_route(dst, src);
527 	if (!hdev)
528 		return NULL;
529 
530 	conn = hci_conn_hash_lookup_ba(hdev, ACL_LINK, dst);
531 
532 	hci_dev_put(hdev);
533 
534 	return conn ? &conn->dev : NULL;
535 }
536 
537 int bnep_add_connection(struct bnep_connadd_req *req, struct socket *sock)
538 {
539 	struct net_device *dev;
540 	struct bnep_session *s, *ss;
541 	u8 dst[ETH_ALEN], src[ETH_ALEN];
542 	int err;
543 
544 	BT_DBG("");
545 
546 	baswap((void *) dst, &bt_sk(sock->sk)->dst);
547 	baswap((void *) src, &bt_sk(sock->sk)->src);
548 
549 	/* session struct allocated as private part of net_device */
550 	dev = alloc_netdev(sizeof(struct bnep_session),
551 			   (*req->device) ? req->device : "bnep%d",
552 			   bnep_net_setup);
553 	if (!dev)
554 		return -ENOMEM;
555 
556 	down_write(&bnep_session_sem);
557 
558 	ss = __bnep_get_session(dst);
559 	if (ss && ss->state == BT_CONNECTED) {
560 		err = -EEXIST;
561 		goto failed;
562 	}
563 
564 	s = dev->priv;
565 
566 	/* This is rx header therefore addresses are swapped.
567 	 * ie eh.h_dest is our local address. */
568 	memcpy(s->eh.h_dest,   &src, ETH_ALEN);
569 	memcpy(s->eh.h_source, &dst, ETH_ALEN);
570 	memcpy(dev->dev_addr, s->eh.h_dest, ETH_ALEN);
571 
572 	s->dev   = dev;
573 	s->sock  = sock;
574 	s->role  = req->role;
575 	s->state = BT_CONNECTED;
576 
577 	s->msg.msg_flags = MSG_NOSIGNAL;
578 
579 #ifdef CONFIG_BT_BNEP_MC_FILTER
580 	/* Set default mc filter */
581 	set_bit(bnep_mc_hash(dev->broadcast), (ulong *) &s->mc_filter);
582 #endif
583 
584 #ifdef CONFIG_BT_BNEP_PROTO_FILTER
585 	/* Set default protocol filter */
586 	bnep_set_default_proto_filter(s);
587 #endif
588 
589 	SET_NETDEV_DEV(dev, bnep_get_device(s));
590 
591 	err = register_netdev(dev);
592 	if (err) {
593 		goto failed;
594 	}
595 
596 	__bnep_link_session(s);
597 
598 	err = kernel_thread(bnep_session, s, CLONE_KERNEL);
599 	if (err < 0) {
600 		/* Session thread start failed, gotta cleanup. */
601 		unregister_netdev(dev);
602 		__bnep_unlink_session(s);
603 		goto failed;
604 	}
605 
606 	up_write(&bnep_session_sem);
607 	strcpy(req->device, dev->name);
608 	return 0;
609 
610 failed:
611 	up_write(&bnep_session_sem);
612 	free_netdev(dev);
613 	return err;
614 }
615 
616 int bnep_del_connection(struct bnep_conndel_req *req)
617 {
618 	struct bnep_session *s;
619 	int  err = 0;
620 
621 	BT_DBG("");
622 
623 	down_read(&bnep_session_sem);
624 
625 	s = __bnep_get_session(req->dst);
626 	if (s) {
627 		/* Wakeup user-space which is polling for socket errors.
628 		 * This is temporary hack untill we have shutdown in L2CAP */
629 		s->sock->sk->sk_err = EUNATCH;
630 
631 		/* Kill session thread */
632 		atomic_inc(&s->killed);
633 		wake_up_interruptible(s->sock->sk->sk_sleep);
634 	} else
635 		err = -ENOENT;
636 
637 	up_read(&bnep_session_sem);
638 	return err;
639 }
640 
641 static void __bnep_copy_ci(struct bnep_conninfo *ci, struct bnep_session *s)
642 {
643 	memcpy(ci->dst, s->eh.h_source, ETH_ALEN);
644 	strcpy(ci->device, s->dev->name);
645 	ci->flags = s->flags;
646 	ci->state = s->state;
647 	ci->role  = s->role;
648 }
649 
650 int bnep_get_connlist(struct bnep_connlist_req *req)
651 {
652 	struct list_head *p;
653 	int err = 0, n = 0;
654 
655 	down_read(&bnep_session_sem);
656 
657 	list_for_each(p, &bnep_session_list) {
658 		struct bnep_session *s;
659 		struct bnep_conninfo ci;
660 
661 		s = list_entry(p, struct bnep_session, list);
662 
663 		__bnep_copy_ci(&ci, s);
664 
665 		if (copy_to_user(req->ci, &ci, sizeof(ci))) {
666 			err = -EFAULT;
667 			break;
668 		}
669 
670 		if (++n >= req->cnum)
671 			break;
672 
673 		req->ci++;
674 	}
675 	req->cnum = n;
676 
677 	up_read(&bnep_session_sem);
678 	return err;
679 }
680 
681 int bnep_get_conninfo(struct bnep_conninfo *ci)
682 {
683 	struct bnep_session *s;
684 	int err = 0;
685 
686 	down_read(&bnep_session_sem);
687 
688 	s = __bnep_get_session(ci->dst);
689 	if (s)
690 		__bnep_copy_ci(ci, s);
691 	else
692 		err = -ENOENT;
693 
694 	up_read(&bnep_session_sem);
695 	return err;
696 }
697 
698 static int __init bnep_init(void)
699 {
700 	char flt[50] = "";
701 
702 	l2cap_load();
703 
704 #ifdef CONFIG_BT_BNEP_PROTO_FILTER
705 	strcat(flt, "protocol ");
706 #endif
707 
708 #ifdef CONFIG_BT_BNEP_MC_FILTER
709 	strcat(flt, "multicast");
710 #endif
711 
712 	BT_INFO("BNEP (Ethernet Emulation) ver %s", VERSION);
713 	if (flt[0])
714 		BT_INFO("BNEP filters: %s", flt);
715 
716 	bnep_sock_init();
717 	return 0;
718 }
719 
720 static void __exit bnep_exit(void)
721 {
722 	bnep_sock_cleanup();
723 }
724 
725 module_init(bnep_init);
726 module_exit(bnep_exit);
727 
728 MODULE_AUTHOR("David Libault <david.libault@inventel.fr>, Maxim Krasnyansky <maxk@qualcomm.com>");
729 MODULE_DESCRIPTION("Bluetooth BNEP ver " VERSION);
730 MODULE_VERSION(VERSION);
731 MODULE_LICENSE("GPL");
732 MODULE_ALIAS("bt-proto-4");
733