xref: /openbmc/linux/net/bluetooth/bnep/core.c (revision f15cbe6f1a4b4d9df59142fc8e4abb973302cf44) 
1 /*
2    BNEP implementation for Linux Bluetooth stack (BlueZ).
3    Copyright (C) 2001-2002 Inventel Systemes
4    Written 2001-2002 by
5 	Clément 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 #include <linux/module.h>
29 
30 #include <linux/kernel.h>
31 #include <linux/sched.h>
32 #include <linux/signal.h>
33 #include <linux/init.h>
34 #include <linux/wait.h>
35 #include <linux/freezer.h>
36 #include <linux/errno.h>
37 #include <linux/net.h>
38 #include <net/sock.h>
39 
40 #include <linux/socket.h>
41 #include <linux/file.h>
42 
43 #include <linux/netdevice.h>
44 #include <linux/etherdevice.h>
45 #include <linux/skbuff.h>
46 
47 #include <asm/unaligned.h>
48 
49 #include <net/bluetooth/bluetooth.h>
50 #include <net/bluetooth/hci_core.h>
51 #include <net/bluetooth/l2cap.h>
52 
53 #include "bnep.h"
54 
55 #ifndef CONFIG_BT_BNEP_DEBUG
56 #undef  BT_DBG
57 #define BT_DBG(D...)
58 #endif
59 
60 #define VERSION "1.2"
61 
62 static LIST_HEAD(bnep_session_list);
63 static DECLARE_RWSEM(bnep_session_sem);
64 
65 static struct bnep_session *__bnep_get_session(u8 *dst)
66 {
67 	struct bnep_session *s;
68 	struct list_head *p;
69 
70 	BT_DBG("");
71 
72 	list_for_each(p, &bnep_session_list) {
73 		s = list_entry(p, struct bnep_session, list);
74 		if (!compare_ether_addr(dst, s->eh.h_source))
75 			return s;
76 	}
77 	return NULL;
78 }
79 
80 static void __bnep_link_session(struct bnep_session *s)
81 {
82 	/* It's safe to call __module_get() here because sessions are added
83 	   by the socket layer which has to hold the refference to this module.
84 	 */
85 	__module_get(THIS_MODULE);
86 	list_add(&s->list, &bnep_session_list);
87 }
88 
89 static void __bnep_unlink_session(struct bnep_session *s)
90 {
91 	list_del(&s->list);
92 	module_put(THIS_MODULE);
93 }
94 
95 static int bnep_send(struct bnep_session *s, void *data, size_t len)
96 {
97 	struct socket *sock = s->sock;
98 	struct kvec iv = { data, len };
99 
100 	return kernel_sendmsg(sock, &s->msg, &iv, 1, len);
101 }
102 
103 static int bnep_send_rsp(struct bnep_session *s, u8 ctrl, u16 resp)
104 {
105 	struct bnep_control_rsp rsp;
106 	rsp.type = BNEP_CONTROL;
107 	rsp.ctrl = ctrl;
108 	rsp.resp = htons(resp);
109 	return bnep_send(s, &rsp, sizeof(rsp));
110 }
111 
112 #ifdef CONFIG_BT_BNEP_PROTO_FILTER
113 static inline void bnep_set_default_proto_filter(struct bnep_session *s)
114 {
115 	/* (IPv4, ARP)  */
116 	s->proto_filter[0].start = ETH_P_IP;
117 	s->proto_filter[0].end   = ETH_P_ARP;
118 	/* (RARP, AppleTalk) */
119 	s->proto_filter[1].start = ETH_P_RARP;
120 	s->proto_filter[1].end   = ETH_P_AARP;
121 	/* (IPX, IPv6) */
122 	s->proto_filter[2].start = ETH_P_IPX;
123 	s->proto_filter[2].end   = ETH_P_IPV6;
124 }
125 #endif
126 
127 static int bnep_ctrl_set_netfilter(struct bnep_session *s, __be16 *data, int len)
128 {
129 	int n;
130 
131 	if (len < 2)
132 		return -EILSEQ;
133 
134 	n = get_unaligned_be16(data);
135 	data++; len -= 2;
136 
137 	if (len < n)
138 		return -EILSEQ;
139 
140 	BT_DBG("filter len %d", n);
141 
142 #ifdef CONFIG_BT_BNEP_PROTO_FILTER
143 	n /= 4;
144 	if (n <= BNEP_MAX_PROTO_FILTERS) {
145 		struct bnep_proto_filter *f = s->proto_filter;
146 		int i;
147 
148 		for (i = 0; i < n; i++) {
149 			f[i].start = get_unaligned_be16(data++);
150 			f[i].end   = get_unaligned_be16(data++);
151 
152 			BT_DBG("proto filter start %d end %d",
153 				f[i].start, f[i].end);
154 		}
155 
156 		if (i < BNEP_MAX_PROTO_FILTERS)
157 			memset(f + i, 0, sizeof(*f));
158 
159 		if (n == 0)
160 			bnep_set_default_proto_filter(s);
161 
162 		bnep_send_rsp(s, BNEP_FILTER_NET_TYPE_RSP, BNEP_SUCCESS);
163 	} else {
164 		bnep_send_rsp(s, BNEP_FILTER_NET_TYPE_RSP, BNEP_FILTER_LIMIT_REACHED);
165 	}
166 #else
167 	bnep_send_rsp(s, BNEP_FILTER_NET_TYPE_RSP, BNEP_FILTER_UNSUPPORTED_REQ);
168 #endif
169 	return 0;
170 }
171 
172 static int bnep_ctrl_set_mcfilter(struct bnep_session *s, u8 *data, int len)
173 {
174 	int n;
175 
176 	if (len < 2)
177 		return -EILSEQ;
178 
179 	n = get_unaligned_be16(data);
180 	data += 2; len -= 2;
181 
182 	if (len < n)
183 		return -EILSEQ;
184 
185 	BT_DBG("filter len %d", n);
186 
187 #ifdef CONFIG_BT_BNEP_MC_FILTER
188 	n /= (ETH_ALEN * 2);
189 
190 	if (n > 0) {
191 		s->mc_filter = 0;
192 
193 		/* Always send broadcast */
194 		set_bit(bnep_mc_hash(s->dev->broadcast), (ulong *) &s->mc_filter);
195 
196 		/* Add address ranges to the multicast hash */
197 		for (; n > 0; n--) {
198 			u8 a1[6], *a2;
199 
200 			memcpy(a1, data, ETH_ALEN); data += ETH_ALEN;
201 			a2 = data; data += ETH_ALEN;
202 
203 			BT_DBG("mc filter %s -> %s",
204 				batostr((void *) a1), batostr((void *) a2));
205 
206 			#define INCA(a) { int i = 5; while (i >=0 && ++a[i--] == 0); }
207 
208 			/* Iterate from a1 to a2 */
209 			set_bit(bnep_mc_hash(a1), (ulong *) &s->mc_filter);
210 			while (memcmp(a1, a2, 6) < 0 && s->mc_filter != ~0LL) {
211 				INCA(a1);
212 				set_bit(bnep_mc_hash(a1), (ulong *) &s->mc_filter);
213 			}
214 		}
215 	}
216 
217 	BT_DBG("mc filter hash 0x%llx", s->mc_filter);
218 
219 	bnep_send_rsp(s, BNEP_FILTER_MULTI_ADDR_RSP, BNEP_SUCCESS);
220 #else
221 	bnep_send_rsp(s, BNEP_FILTER_MULTI_ADDR_RSP, BNEP_FILTER_UNSUPPORTED_REQ);
222 #endif
223 	return 0;
224 }
225 
226 static int bnep_rx_control(struct bnep_session *s, void *data, int len)
227 {
228 	u8  cmd = *(u8 *)data;
229 	int err = 0;
230 
231 	data++; len--;
232 
233 	switch (cmd) {
234 	case BNEP_CMD_NOT_UNDERSTOOD:
235 	case BNEP_SETUP_CONN_REQ:
236 	case BNEP_SETUP_CONN_RSP:
237 	case BNEP_FILTER_NET_TYPE_RSP:
238 	case BNEP_FILTER_MULTI_ADDR_RSP:
239 		/* Ignore these for now */
240 		break;
241 
242 	case BNEP_FILTER_NET_TYPE_SET:
243 		err = bnep_ctrl_set_netfilter(s, data, len);
244 		break;
245 
246 	case BNEP_FILTER_MULTI_ADDR_SET:
247 		err = bnep_ctrl_set_mcfilter(s, data, len);
248 		break;
249 
250 	default: {
251 			u8 pkt[3];
252 			pkt[0] = BNEP_CONTROL;
253 			pkt[1] = BNEP_CMD_NOT_UNDERSTOOD;
254 			pkt[2] = cmd;
255 			bnep_send(s, pkt, sizeof(pkt));
256 		}
257 		break;
258 	}
259 
260 	return err;
261 }
262 
263 static int bnep_rx_extension(struct bnep_session *s, struct sk_buff *skb)
264 {
265 	struct bnep_ext_hdr *h;
266 	int err = 0;
267 
268 	do {
269 		h = (void *) skb->data;
270 		if (!skb_pull(skb, sizeof(*h))) {
271 			err = -EILSEQ;
272 			break;
273 		}
274 
275 		BT_DBG("type 0x%x len %d", h->type, h->len);
276 
277 		switch (h->type & BNEP_TYPE_MASK) {
278 		case BNEP_EXT_CONTROL:
279 			bnep_rx_control(s, skb->data, skb->len);
280 			break;
281 
282 		default:
283 			/* Unknown extension, skip it. */
284 			break;
285 		}
286 
287 		if (!skb_pull(skb, h->len)) {
288 			err = -EILSEQ;
289 			break;
290 		}
291 	} while (!err && (h->type & BNEP_EXT_HEADER));
292 
293 	return err;
294 }
295 
296 static u8 __bnep_rx_hlen[] = {
297 	ETH_HLEN,     /* BNEP_GENERAL */
298 	0,            /* BNEP_CONTROL */
299 	2,            /* BNEP_COMPRESSED */
300 	ETH_ALEN + 2, /* BNEP_COMPRESSED_SRC_ONLY */
301 	ETH_ALEN + 2  /* BNEP_COMPRESSED_DST_ONLY */
302 };
303 #define BNEP_RX_TYPES	(sizeof(__bnep_rx_hlen) - 1)
304 
305 static inline int bnep_rx_frame(struct bnep_session *s, struct sk_buff *skb)
306 {
307 	struct net_device *dev = s->dev;
308 	struct sk_buff *nskb;
309 	u8 type;
310 
311 	dev->last_rx = jiffies;
312 	s->stats.rx_bytes += skb->len;
313 
314 	type = *(u8 *) skb->data; skb_pull(skb, 1);
315 
316 	if ((type & BNEP_TYPE_MASK) > BNEP_RX_TYPES)
317 		goto badframe;
318 
319 	if ((type & BNEP_TYPE_MASK) == BNEP_CONTROL) {
320 		bnep_rx_control(s, skb->data, skb->len);
321 		kfree_skb(skb);
322 		return 0;
323 	}
324 
325 	skb_reset_mac_header(skb);
326 
327 	/* Verify and pull out header */
328 	if (!skb_pull(skb, __bnep_rx_hlen[type & BNEP_TYPE_MASK]))
329 		goto badframe;
330 
331 	s->eh.h_proto = get_unaligned((__be16 *) (skb->data - 2));
332 
333 	if (type & BNEP_EXT_HEADER) {
334 		if (bnep_rx_extension(s, skb) < 0)
335 			goto badframe;
336 	}
337 
338 	/* Strip 802.1p header */
339 	if (ntohs(s->eh.h_proto) == 0x8100) {
340 		if (!skb_pull(skb, 4))
341 			goto badframe;
342 		s->eh.h_proto = get_unaligned((__be16 *) (skb->data - 2));
343 	}
344 
345 	/* We have to alloc new skb and copy data here :(. Because original skb
346 	 * may not be modified and because of the alignment requirements. */
347 	nskb = alloc_skb(2 + ETH_HLEN + skb->len, GFP_KERNEL);
348 	if (!nskb) {
349 		s->stats.rx_dropped++;
350 		kfree_skb(skb);
351 		return -ENOMEM;
352 	}
353 	skb_reserve(nskb, 2);
354 
355 	/* Decompress header and construct ether frame */
356 	switch (type & BNEP_TYPE_MASK) {
357 	case BNEP_COMPRESSED:
358 		memcpy(__skb_put(nskb, ETH_HLEN), &s->eh, ETH_HLEN);
359 		break;
360 
361 	case BNEP_COMPRESSED_SRC_ONLY:
362 		memcpy(__skb_put(nskb, ETH_ALEN), s->eh.h_dest, ETH_ALEN);
363 		memcpy(__skb_put(nskb, ETH_ALEN), skb_mac_header(skb), ETH_ALEN);
364 		put_unaligned(s->eh.h_proto, (__be16 *) __skb_put(nskb, 2));
365 		break;
366 
367 	case BNEP_COMPRESSED_DST_ONLY:
368 		memcpy(__skb_put(nskb, ETH_ALEN), skb_mac_header(skb),
369 		       ETH_ALEN);
370 		memcpy(__skb_put(nskb, ETH_ALEN + 2), s->eh.h_source,
371 		       ETH_ALEN + 2);
372 		break;
373 
374 	case BNEP_GENERAL:
375 		memcpy(__skb_put(nskb, ETH_ALEN * 2), skb_mac_header(skb),
376 		       ETH_ALEN * 2);
377 		put_unaligned(s->eh.h_proto, (__be16 *) __skb_put(nskb, 2));
378 		break;
379 	}
380 
381 	skb_copy_from_linear_data(skb, __skb_put(nskb, skb->len), skb->len);
382 	kfree_skb(skb);
383 
384 	s->stats.rx_packets++;
385 	nskb->ip_summed = CHECKSUM_NONE;
386 	nskb->protocol  = eth_type_trans(nskb, dev);
387 	netif_rx_ni(nskb);
388 	return 0;
389 
390 badframe:
391 	s->stats.rx_errors++;
392 	kfree_skb(skb);
393 	return 0;
394 }
395 
396 static u8 __bnep_tx_types[] = {
397 	BNEP_GENERAL,
398 	BNEP_COMPRESSED_SRC_ONLY,
399 	BNEP_COMPRESSED_DST_ONLY,
400 	BNEP_COMPRESSED
401 };
402 
403 static inline int bnep_tx_frame(struct bnep_session *s, struct sk_buff *skb)
404 {
405 	struct ethhdr *eh = (void *) skb->data;
406 	struct socket *sock = s->sock;
407 	struct kvec iv[3];
408 	int len = 0, il = 0;
409 	u8 type = 0;
410 
411 	BT_DBG("skb %p dev %p type %d", skb, skb->dev, skb->pkt_type);
412 
413 	if (!skb->dev) {
414 		/* Control frame sent by us */
415 		goto send;
416 	}
417 
418 	iv[il++] = (struct kvec) { &type, 1 };
419 	len++;
420 
421 	if (!compare_ether_addr(eh->h_dest, s->eh.h_source))
422 		type |= 0x01;
423 
424 	if (!compare_ether_addr(eh->h_source, s->eh.h_dest))
425 		type |= 0x02;
426 
427 	if (type)
428 		skb_pull(skb, ETH_ALEN * 2);
429 
430 	type = __bnep_tx_types[type];
431 	switch (type) {
432 	case BNEP_COMPRESSED_SRC_ONLY:
433 		iv[il++] = (struct kvec) { eh->h_source, ETH_ALEN };
434 		len += ETH_ALEN;
435 		break;
436 
437 	case BNEP_COMPRESSED_DST_ONLY:
438 		iv[il++] = (struct kvec) { eh->h_dest, ETH_ALEN };
439 		len += ETH_ALEN;
440 		break;
441 	}
442 
443 send:
444 	iv[il++] = (struct kvec) { skb->data, skb->len };
445 	len += skb->len;
446 
447 	/* FIXME: linearize skb */
448 	{
449 		len = kernel_sendmsg(sock, &s->msg, iv, il, len);
450 	}
451 	kfree_skb(skb);
452 
453 	if (len > 0) {
454 		s->stats.tx_bytes += len;
455 		s->stats.tx_packets++;
456 		return 0;
457 	}
458 
459 	return len;
460 }
461 
462 static int bnep_session(void *arg)
463 {
464 	struct bnep_session *s = arg;
465 	struct net_device *dev = s->dev;
466 	struct sock *sk = s->sock->sk;
467 	struct sk_buff *skb;
468 	wait_queue_t wait;
469 
470 	BT_DBG("");
471 
472 	daemonize("kbnepd %s", dev->name);
473 	set_user_nice(current, -15);
474 
475 	init_waitqueue_entry(&wait, current);
476 	add_wait_queue(sk->sk_sleep, &wait);
477 	while (!atomic_read(&s->killed)) {
478 		set_current_state(TASK_INTERRUPTIBLE);
479 
480 		// RX
481 		while ((skb = skb_dequeue(&sk->sk_receive_queue))) {
482 			skb_orphan(skb);
483 			bnep_rx_frame(s, skb);
484 		}
485 
486 		if (sk->sk_state != BT_CONNECTED)
487 			break;
488 
489 		// TX
490 		while ((skb = skb_dequeue(&sk->sk_write_queue)))
491 			if (bnep_tx_frame(s, skb))
492 				break;
493 		netif_wake_queue(dev);
494 
495 		schedule();
496 	}
497 	set_current_state(TASK_RUNNING);
498 	remove_wait_queue(sk->sk_sleep, &wait);
499 
500 	/* Cleanup session */
501 	down_write(&bnep_session_sem);
502 
503 	/* Delete network device */
504 	unregister_netdev(dev);
505 
506 	/* Wakeup user-space polling for socket errors */
507 	s->sock->sk->sk_err = EUNATCH;
508 
509 	wake_up_interruptible(s->sock->sk->sk_sleep);
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