xref: /openbmc/linux/net/bluetooth/bnep/core.c (revision a09d2831) 
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 #define VERSION "1.3"
56 
57 static int compress_src = 1;
58 static int compress_dst = 1;
59 
60 static LIST_HEAD(bnep_session_list);
61 static DECLARE_RWSEM(bnep_session_sem);
62 
63 static struct bnep_session *__bnep_get_session(u8 *dst)
64 {
65 	struct bnep_session *s;
66 	struct list_head *p;
67 
68 	BT_DBG("");
69 
70 	list_for_each(p, &bnep_session_list) {
71 		s = list_entry(p, struct bnep_session, list);
72 		if (!compare_ether_addr(dst, s->eh.h_source))
73 			return s;
74 	}
75 	return NULL;
76 }
77 
78 static void __bnep_link_session(struct bnep_session *s)
79 {
80 	/* It's safe to call __module_get() here because sessions are added
81 	   by the socket layer which has to hold the reference to this module.
82 	 */
83 	__module_get(THIS_MODULE);
84 	list_add(&s->list, &bnep_session_list);
85 }
86 
87 static void __bnep_unlink_session(struct bnep_session *s)
88 {
89 	list_del(&s->list);
90 	module_put(THIS_MODULE);
91 }
92 
93 static int bnep_send(struct bnep_session *s, void *data, size_t len)
94 {
95 	struct socket *sock = s->sock;
96 	struct kvec iv = { data, len };
97 
98 	return kernel_sendmsg(sock, &s->msg, &iv, 1, len);
99 }
100 
101 static int bnep_send_rsp(struct bnep_session *s, u8 ctrl, u16 resp)
102 {
103 	struct bnep_control_rsp rsp;
104 	rsp.type = BNEP_CONTROL;
105 	rsp.ctrl = ctrl;
106 	rsp.resp = htons(resp);
107 	return bnep_send(s, &rsp, sizeof(rsp));
108 }
109 
110 #ifdef CONFIG_BT_BNEP_PROTO_FILTER
111 static inline void bnep_set_default_proto_filter(struct bnep_session *s)
112 {
113 	/* (IPv4, ARP)  */
114 	s->proto_filter[0].start = ETH_P_IP;
115 	s->proto_filter[0].end   = ETH_P_ARP;
116 	/* (RARP, AppleTalk) */
117 	s->proto_filter[1].start = ETH_P_RARP;
118 	s->proto_filter[1].end   = ETH_P_AARP;
119 	/* (IPX, IPv6) */
120 	s->proto_filter[2].start = ETH_P_IPX;
121 	s->proto_filter[2].end   = ETH_P_IPV6;
122 }
123 #endif
124 
125 static int bnep_ctrl_set_netfilter(struct bnep_session *s, __be16 *data, int len)
126 {
127 	int n;
128 
129 	if (len < 2)
130 		return -EILSEQ;
131 
132 	n = get_unaligned_be16(data);
133 	data++; len -= 2;
134 
135 	if (len < n)
136 		return -EILSEQ;
137 
138 	BT_DBG("filter len %d", n);
139 
140 #ifdef CONFIG_BT_BNEP_PROTO_FILTER
141 	n /= 4;
142 	if (n <= BNEP_MAX_PROTO_FILTERS) {
143 		struct bnep_proto_filter *f = s->proto_filter;
144 		int i;
145 
146 		for (i = 0; i < n; i++) {
147 			f[i].start = get_unaligned_be16(data++);
148 			f[i].end   = get_unaligned_be16(data++);
149 
150 			BT_DBG("proto filter start %d end %d",
151 				f[i].start, f[i].end);
152 		}
153 
154 		if (i < BNEP_MAX_PROTO_FILTERS)
155 			memset(f + i, 0, sizeof(*f));
156 
157 		if (n == 0)
158 			bnep_set_default_proto_filter(s);
159 
160 		bnep_send_rsp(s, BNEP_FILTER_NET_TYPE_RSP, BNEP_SUCCESS);
161 	} else {
162 		bnep_send_rsp(s, BNEP_FILTER_NET_TYPE_RSP, BNEP_FILTER_LIMIT_REACHED);
163 	}
164 #else
165 	bnep_send_rsp(s, BNEP_FILTER_NET_TYPE_RSP, BNEP_FILTER_UNSUPPORTED_REQ);
166 #endif
167 	return 0;
168 }
169 
170 static int bnep_ctrl_set_mcfilter(struct bnep_session *s, u8 *data, int len)
171 {
172 	int n;
173 
174 	if (len < 2)
175 		return -EILSEQ;
176 
177 	n = get_unaligned_be16(data);
178 	data += 2; len -= 2;
179 
180 	if (len < n)
181 		return -EILSEQ;
182 
183 	BT_DBG("filter len %d", n);
184 
185 #ifdef CONFIG_BT_BNEP_MC_FILTER
186 	n /= (ETH_ALEN * 2);
187 
188 	if (n > 0) {
189 		s->mc_filter = 0;
190 
191 		/* Always send broadcast */
192 		set_bit(bnep_mc_hash(s->dev->broadcast), (ulong *) &s->mc_filter);
193 
194 		/* Add address ranges to the multicast hash */
195 		for (; n > 0; n--) {
196 			u8 a1[6], *a2;
197 
198 			memcpy(a1, data, ETH_ALEN); data += ETH_ALEN;
199 			a2 = data; data += ETH_ALEN;
200 
201 			BT_DBG("mc filter %s -> %s",
202 				batostr((void *) a1), batostr((void *) a2));
203 
204 			#define INCA(a) { int i = 5; while (i >=0 && ++a[i--] == 0); }
205 
206 			/* Iterate from a1 to a2 */
207 			set_bit(bnep_mc_hash(a1), (ulong *) &s->mc_filter);
208 			while (memcmp(a1, a2, 6) < 0 && s->mc_filter != ~0LL) {
209 				INCA(a1);
210 				set_bit(bnep_mc_hash(a1), (ulong *) &s->mc_filter);
211 			}
212 		}
213 	}
214 
215 	BT_DBG("mc filter hash 0x%llx", s->mc_filter);
216 
217 	bnep_send_rsp(s, BNEP_FILTER_MULTI_ADDR_RSP, BNEP_SUCCESS);
218 #else
219 	bnep_send_rsp(s, BNEP_FILTER_MULTI_ADDR_RSP, BNEP_FILTER_UNSUPPORTED_REQ);
220 #endif
221 	return 0;
222 }
223 
224 static int bnep_rx_control(struct bnep_session *s, void *data, int len)
225 {
226 	u8  cmd = *(u8 *)data;
227 	int err = 0;
228 
229 	data++; len--;
230 
231 	switch (cmd) {
232 	case BNEP_CMD_NOT_UNDERSTOOD:
233 	case BNEP_SETUP_CONN_RSP:
234 	case BNEP_FILTER_NET_TYPE_RSP:
235 	case BNEP_FILTER_MULTI_ADDR_RSP:
236 		/* Ignore these for now */
237 		break;
238 
239 	case BNEP_FILTER_NET_TYPE_SET:
240 		err = bnep_ctrl_set_netfilter(s, data, len);
241 		break;
242 
243 	case BNEP_FILTER_MULTI_ADDR_SET:
244 		err = bnep_ctrl_set_mcfilter(s, data, len);
245 		break;
246 
247 	case BNEP_SETUP_CONN_REQ:
248 		err = bnep_send_rsp(s, BNEP_SETUP_CONN_RSP, BNEP_CONN_NOT_ALLOWED);
249 		break;
250 
251 	default: {
252 			u8 pkt[3];
253 			pkt[0] = BNEP_CONTROL;
254 			pkt[1] = BNEP_CMD_NOT_UNDERSTOOD;
255 			pkt[2] = cmd;
256 			bnep_send(s, pkt, sizeof(pkt));
257 		}
258 		break;
259 	}
260 
261 	return err;
262 }
263 
264 static int bnep_rx_extension(struct bnep_session *s, struct sk_buff *skb)
265 {
266 	struct bnep_ext_hdr *h;
267 	int err = 0;
268 
269 	do {
270 		h = (void *) skb->data;
271 		if (!skb_pull(skb, sizeof(*h))) {
272 			err = -EILSEQ;
273 			break;
274 		}
275 
276 		BT_DBG("type 0x%x len %d", h->type, h->len);
277 
278 		switch (h->type & BNEP_TYPE_MASK) {
279 		case BNEP_EXT_CONTROL:
280 			bnep_rx_control(s, skb->data, skb->len);
281 			break;
282 
283 		default:
284 			/* Unknown extension, skip it. */
285 			break;
286 		}
287 
288 		if (!skb_pull(skb, h->len)) {
289 			err = -EILSEQ;
290 			break;
291 		}
292 	} while (!err && (h->type & BNEP_EXT_HEADER));
293 
294 	return err;
295 }
296 
297 static u8 __bnep_rx_hlen[] = {
298 	ETH_HLEN,     /* BNEP_GENERAL */
299 	0,            /* BNEP_CONTROL */
300 	2,            /* BNEP_COMPRESSED */
301 	ETH_ALEN + 2, /* BNEP_COMPRESSED_SRC_ONLY */
302 	ETH_ALEN + 2  /* BNEP_COMPRESSED_DST_ONLY */
303 };
304 #define BNEP_RX_TYPES	(sizeof(__bnep_rx_hlen) - 1)
305 
306 static inline int bnep_rx_frame(struct bnep_session *s, struct sk_buff *skb)
307 {
308 	struct net_device *dev = s->dev;
309 	struct sk_buff *nskb;
310 	u8 type;
311 
312 	dev->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 		dev->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 	dev->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 	dev->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 (compress_src && !compare_ether_addr(eh->h_dest, s->eh.h_source))
422 		type |= 0x01;
423 
424 	if (compress_dst && !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->dev->stats.tx_bytes += len;
455 		s->dev->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 static struct device_type bnep_type = {
540 	.name	= "bluetooth",
541 };
542 
543 int bnep_add_connection(struct bnep_connadd_req *req, struct socket *sock)
544 {
545 	struct net_device *dev;
546 	struct bnep_session *s, *ss;
547 	u8 dst[ETH_ALEN], src[ETH_ALEN];
548 	int err;
549 
550 	BT_DBG("");
551 
552 	baswap((void *) dst, &bt_sk(sock->sk)->dst);
553 	baswap((void *) src, &bt_sk(sock->sk)->src);
554 
555 	/* session struct allocated as private part of net_device */
556 	dev = alloc_netdev(sizeof(struct bnep_session),
557 			   (*req->device) ? req->device : "bnep%d",
558 			   bnep_net_setup);
559 	if (!dev)
560 		return -ENOMEM;
561 
562 	down_write(&bnep_session_sem);
563 
564 	ss = __bnep_get_session(dst);
565 	if (ss && ss->state == BT_CONNECTED) {
566 		err = -EEXIST;
567 		goto failed;
568 	}
569 
570 	s = netdev_priv(dev);
571 
572 	/* This is rx header therefore addresses are swapped.
573 	 * ie eh.h_dest is our local address. */
574 	memcpy(s->eh.h_dest,   &src, ETH_ALEN);
575 	memcpy(s->eh.h_source, &dst, ETH_ALEN);
576 	memcpy(dev->dev_addr, s->eh.h_dest, ETH_ALEN);
577 
578 	s->dev   = dev;
579 	s->sock  = sock;
580 	s->role  = req->role;
581 	s->state = BT_CONNECTED;
582 
583 	s->msg.msg_flags = MSG_NOSIGNAL;
584 
585 #ifdef CONFIG_BT_BNEP_MC_FILTER
586 	/* Set default mc filter */
587 	set_bit(bnep_mc_hash(dev->broadcast), (ulong *) &s->mc_filter);
588 #endif
589 
590 #ifdef CONFIG_BT_BNEP_PROTO_FILTER
591 	/* Set default protocol filter */
592 	bnep_set_default_proto_filter(s);
593 #endif
594 
595 	SET_NETDEV_DEV(dev, bnep_get_device(s));
596 	SET_NETDEV_DEVTYPE(dev, &bnep_type);
597 
598 	err = register_netdev(dev);
599 	if (err) {
600 		goto failed;
601 	}
602 
603 	__bnep_link_session(s);
604 
605 	err = kernel_thread(bnep_session, s, CLONE_KERNEL);
606 	if (err < 0) {
607 		/* Session thread start failed, gotta cleanup. */
608 		unregister_netdev(dev);
609 		__bnep_unlink_session(s);
610 		goto failed;
611 	}
612 
613 	up_write(&bnep_session_sem);
614 	strcpy(req->device, dev->name);
615 	return 0;
616 
617 failed:
618 	up_write(&bnep_session_sem);
619 	free_netdev(dev);
620 	return err;
621 }
622 
623 int bnep_del_connection(struct bnep_conndel_req *req)
624 {
625 	struct bnep_session *s;
626 	int  err = 0;
627 
628 	BT_DBG("");
629 
630 	down_read(&bnep_session_sem);
631 
632 	s = __bnep_get_session(req->dst);
633 	if (s) {
634 		/* Wakeup user-space which is polling for socket errors.
635 		 * This is temporary hack until we have shutdown in L2CAP */
636 		s->sock->sk->sk_err = EUNATCH;
637 
638 		/* Kill session thread */
639 		atomic_inc(&s->killed);
640 		wake_up_interruptible(s->sock->sk->sk_sleep);
641 	} else
642 		err = -ENOENT;
643 
644 	up_read(&bnep_session_sem);
645 	return err;
646 }
647 
648 static void __bnep_copy_ci(struct bnep_conninfo *ci, struct bnep_session *s)
649 {
650 	memcpy(ci->dst, s->eh.h_source, ETH_ALEN);
651 	strcpy(ci->device, s->dev->name);
652 	ci->flags = s->flags;
653 	ci->state = s->state;
654 	ci->role  = s->role;
655 }
656 
657 int bnep_get_connlist(struct bnep_connlist_req *req)
658 {
659 	struct list_head *p;
660 	int err = 0, n = 0;
661 
662 	down_read(&bnep_session_sem);
663 
664 	list_for_each(p, &bnep_session_list) {
665 		struct bnep_session *s;
666 		struct bnep_conninfo ci;
667 
668 		s = list_entry(p, struct bnep_session, list);
669 
670 		__bnep_copy_ci(&ci, s);
671 
672 		if (copy_to_user(req->ci, &ci, sizeof(ci))) {
673 			err = -EFAULT;
674 			break;
675 		}
676 
677 		if (++n >= req->cnum)
678 			break;
679 
680 		req->ci++;
681 	}
682 	req->cnum = n;
683 
684 	up_read(&bnep_session_sem);
685 	return err;
686 }
687 
688 int bnep_get_conninfo(struct bnep_conninfo *ci)
689 {
690 	struct bnep_session *s;
691 	int err = 0;
692 
693 	down_read(&bnep_session_sem);
694 
695 	s = __bnep_get_session(ci->dst);
696 	if (s)
697 		__bnep_copy_ci(ci, s);
698 	else
699 		err = -ENOENT;
700 
701 	up_read(&bnep_session_sem);
702 	return err;
703 }
704 
705 static int __init bnep_init(void)
706 {
707 	char flt[50] = "";
708 
709 	l2cap_load();
710 
711 #ifdef CONFIG_BT_BNEP_PROTO_FILTER
712 	strcat(flt, "protocol ");
713 #endif
714 
715 #ifdef CONFIG_BT_BNEP_MC_FILTER
716 	strcat(flt, "multicast");
717 #endif
718 
719 	BT_INFO("BNEP (Ethernet Emulation) ver %s", VERSION);
720 	if (flt[0])
721 		BT_INFO("BNEP filters: %s", flt);
722 
723 	bnep_sock_init();
724 	return 0;
725 }
726 
727 static void __exit bnep_exit(void)
728 {
729 	bnep_sock_cleanup();
730 }
731 
732 module_init(bnep_init);
733 module_exit(bnep_exit);
734 
735 module_param(compress_src, bool, 0644);
736 MODULE_PARM_DESC(compress_src, "Compress sources headers");
737 
738 module_param(compress_dst, bool, 0644);
739 MODULE_PARM_DESC(compress_dst, "Compress destination headers");
740 
741 MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
742 MODULE_DESCRIPTION("Bluetooth BNEP ver " VERSION);
743 MODULE_VERSION(VERSION);
744 MODULE_LICENSE("GPL");
745 MODULE_ALIAS("bt-proto-4");
746