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v3.15
  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#include <linux/kthread.h>
 
 
 
 30#include <linux/file.h>
 
 
 31#include <linux/etherdevice.h>
 
 
 32#include <asm/unaligned.h>
 33
 34#include <net/bluetooth/bluetooth.h>
 35#include <net/bluetooth/l2cap.h>
 36#include <net/bluetooth/hci_core.h>
 
 37
 38#include "bnep.h"
 39
 40#define VERSION "1.3"
 41
 42static bool compress_src = true;
 43static bool compress_dst = true;
 44
 45static LIST_HEAD(bnep_session_list);
 46static DECLARE_RWSEM(bnep_session_sem);
 47
 48static struct bnep_session *__bnep_get_session(u8 *dst)
 49{
 50	struct bnep_session *s;
 51
 52	BT_DBG("");
 53
 54	list_for_each_entry(s, &bnep_session_list, list)
 55		if (ether_addr_equal(dst, s->eh.h_source))
 56			return s;
 57
 58	return NULL;
 59}
 60
 61static void __bnep_link_session(struct bnep_session *s)
 62{
 63	list_add(&s->list, &bnep_session_list);
 64}
 65
 66static void __bnep_unlink_session(struct bnep_session *s)
 67{
 68	list_del(&s->list);
 69}
 70
 71static int bnep_send(struct bnep_session *s, void *data, size_t len)
 72{
 73	struct socket *sock = s->sock;
 74	struct kvec iv = { data, len };
 75
 76	return kernel_sendmsg(sock, &s->msg, &iv, 1, len);
 77}
 78
 79static int bnep_send_rsp(struct bnep_session *s, u8 ctrl, u16 resp)
 80{
 81	struct bnep_control_rsp rsp;
 82	rsp.type = BNEP_CONTROL;
 83	rsp.ctrl = ctrl;
 84	rsp.resp = htons(resp);
 85	return bnep_send(s, &rsp, sizeof(rsp));
 86}
 87
 88#ifdef CONFIG_BT_BNEP_PROTO_FILTER
 89static inline void bnep_set_default_proto_filter(struct bnep_session *s)
 90{
 91	/* (IPv4, ARP)  */
 92	s->proto_filter[0].start = ETH_P_IP;
 93	s->proto_filter[0].end   = ETH_P_ARP;
 94	/* (RARP, AppleTalk) */
 95	s->proto_filter[1].start = ETH_P_RARP;
 96	s->proto_filter[1].end   = ETH_P_AARP;
 97	/* (IPX, IPv6) */
 98	s->proto_filter[2].start = ETH_P_IPX;
 99	s->proto_filter[2].end   = ETH_P_IPV6;
100}
101#endif
102
103static int bnep_ctrl_set_netfilter(struct bnep_session *s, __be16 *data, int len)
104{
105	int n;
106
107	if (len < 2)
108		return -EILSEQ;
109
110	n = get_unaligned_be16(data);
111	data++;
112	len -= 2;
113
114	if (len < n)
115		return -EILSEQ;
116
117	BT_DBG("filter len %d", n);
118
119#ifdef CONFIG_BT_BNEP_PROTO_FILTER
120	n /= 4;
121	if (n <= BNEP_MAX_PROTO_FILTERS) {
122		struct bnep_proto_filter *f = s->proto_filter;
123		int i;
124
125		for (i = 0; i < n; i++) {
126			f[i].start = get_unaligned_be16(data++);
127			f[i].end   = get_unaligned_be16(data++);
128
129			BT_DBG("proto filter start %d end %d",
130				f[i].start, f[i].end);
131		}
132
133		if (i < BNEP_MAX_PROTO_FILTERS)
134			memset(f + i, 0, sizeof(*f));
135
136		if (n == 0)
137			bnep_set_default_proto_filter(s);
138
139		bnep_send_rsp(s, BNEP_FILTER_NET_TYPE_RSP, BNEP_SUCCESS);
140	} else {
141		bnep_send_rsp(s, BNEP_FILTER_NET_TYPE_RSP, BNEP_FILTER_LIMIT_REACHED);
142	}
143#else
144	bnep_send_rsp(s, BNEP_FILTER_NET_TYPE_RSP, BNEP_FILTER_UNSUPPORTED_REQ);
145#endif
146	return 0;
147}
148
149static int bnep_ctrl_set_mcfilter(struct bnep_session *s, u8 *data, int len)
150{
151	int n;
152
153	if (len < 2)
154		return -EILSEQ;
155
156	n = get_unaligned_be16(data);
157	data += 2;
158	len -= 2;
159
160	if (len < n)
161		return -EILSEQ;
162
163	BT_DBG("filter len %d", n);
164
165#ifdef CONFIG_BT_BNEP_MC_FILTER
166	n /= (ETH_ALEN * 2);
167
168	if (n > 0) {
169		int i;
170
171		s->mc_filter = 0;
172
173		/* Always send broadcast */
174		set_bit(bnep_mc_hash(s->dev->broadcast), (ulong *) &s->mc_filter);
175
176		/* Add address ranges to the multicast hash */
177		for (; n > 0; n--) {
178			u8 a1[6], *a2;
179
180			memcpy(a1, data, ETH_ALEN);
181			data += ETH_ALEN;
182			a2 = data;
183			data += ETH_ALEN;
184
185			BT_DBG("mc filter %pMR -> %pMR", a1, a2);
 
186
187			/* Iterate from a1 to a2 */
188			set_bit(bnep_mc_hash(a1), (ulong *) &s->mc_filter);
189			while (memcmp(a1, a2, 6) < 0 && s->mc_filter != ~0LL) {
190				/* Increment a1 */
191				i = 5;
192				while (i >= 0 && ++a1[i--] == 0)
193					;
194
195				set_bit(bnep_mc_hash(a1), (ulong *) &s->mc_filter);
196			}
197		}
198	}
199
200	BT_DBG("mc filter hash 0x%llx", s->mc_filter);
201
202	bnep_send_rsp(s, BNEP_FILTER_MULTI_ADDR_RSP, BNEP_SUCCESS);
203#else
204	bnep_send_rsp(s, BNEP_FILTER_MULTI_ADDR_RSP, BNEP_FILTER_UNSUPPORTED_REQ);
205#endif
206	return 0;
207}
208
209static int bnep_rx_control(struct bnep_session *s, void *data, int len)
210{
211	u8  cmd = *(u8 *)data;
212	int err = 0;
213
214	data++;
215	len--;
216
217	switch (cmd) {
218	case BNEP_CMD_NOT_UNDERSTOOD:
219	case BNEP_SETUP_CONN_RSP:
220	case BNEP_FILTER_NET_TYPE_RSP:
221	case BNEP_FILTER_MULTI_ADDR_RSP:
222		/* Ignore these for now */
223		break;
224
225	case BNEP_FILTER_NET_TYPE_SET:
226		err = bnep_ctrl_set_netfilter(s, data, len);
227		break;
228
229	case BNEP_FILTER_MULTI_ADDR_SET:
230		err = bnep_ctrl_set_mcfilter(s, data, len);
231		break;
232
233	case BNEP_SETUP_CONN_REQ:
234		err = bnep_send_rsp(s, BNEP_SETUP_CONN_RSP, BNEP_CONN_NOT_ALLOWED);
235		break;
236
237	default: {
238			u8 pkt[3];
239			pkt[0] = BNEP_CONTROL;
240			pkt[1] = BNEP_CMD_NOT_UNDERSTOOD;
241			pkt[2] = cmd;
242			bnep_send(s, pkt, sizeof(pkt));
243		}
244		break;
245	}
246
247	return err;
248}
249
250static int bnep_rx_extension(struct bnep_session *s, struct sk_buff *skb)
251{
252	struct bnep_ext_hdr *h;
253	int err = 0;
254
255	do {
256		h = (void *) skb->data;
257		if (!skb_pull(skb, sizeof(*h))) {
258			err = -EILSEQ;
259			break;
260		}
261
262		BT_DBG("type 0x%x len %d", h->type, h->len);
263
264		switch (h->type & BNEP_TYPE_MASK) {
265		case BNEP_EXT_CONTROL:
266			bnep_rx_control(s, skb->data, skb->len);
267			break;
268
269		default:
270			/* Unknown extension, skip it. */
271			break;
272		}
273
274		if (!skb_pull(skb, h->len)) {
275			err = -EILSEQ;
276			break;
277		}
278	} while (!err && (h->type & BNEP_EXT_HEADER));
279
280	return err;
281}
282
283static u8 __bnep_rx_hlen[] = {
284	ETH_HLEN,     /* BNEP_GENERAL */
285	0,            /* BNEP_CONTROL */
286	2,            /* BNEP_COMPRESSED */
287	ETH_ALEN + 2, /* BNEP_COMPRESSED_SRC_ONLY */
288	ETH_ALEN + 2  /* BNEP_COMPRESSED_DST_ONLY */
289};
290
291static int bnep_rx_frame(struct bnep_session *s, struct sk_buff *skb)
292{
293	struct net_device *dev = s->dev;
294	struct sk_buff *nskb;
295	u8 type;
296
297	dev->stats.rx_bytes += skb->len;
298
299	type = *(u8 *) skb->data;
300	skb_pull(skb, 1);
301
302	if ((type & BNEP_TYPE_MASK) >= sizeof(__bnep_rx_hlen))
303		goto badframe;
304
305	if ((type & BNEP_TYPE_MASK) == BNEP_CONTROL) {
306		bnep_rx_control(s, skb->data, skb->len);
307		kfree_skb(skb);
308		return 0;
309	}
310
311	skb_reset_mac_header(skb);
312
313	/* Verify and pull out header */
314	if (!skb_pull(skb, __bnep_rx_hlen[type & BNEP_TYPE_MASK]))
315		goto badframe;
316
317	s->eh.h_proto = get_unaligned((__be16 *) (skb->data - 2));
318
319	if (type & BNEP_EXT_HEADER) {
320		if (bnep_rx_extension(s, skb) < 0)
321			goto badframe;
322	}
323
324	/* Strip 802.1p header */
325	if (ntohs(s->eh.h_proto) == ETH_P_8021Q) {
326		if (!skb_pull(skb, 4))
327			goto badframe;
328		s->eh.h_proto = get_unaligned((__be16 *) (skb->data - 2));
329	}
330
331	/* We have to alloc new skb and copy data here :(. Because original skb
332	 * may not be modified and because of the alignment requirements. */
333	nskb = alloc_skb(2 + ETH_HLEN + skb->len, GFP_KERNEL);
334	if (!nskb) {
335		dev->stats.rx_dropped++;
336		kfree_skb(skb);
337		return -ENOMEM;
338	}
339	skb_reserve(nskb, 2);
340
341	/* Decompress header and construct ether frame */
342	switch (type & BNEP_TYPE_MASK) {
343	case BNEP_COMPRESSED:
344		memcpy(__skb_put(nskb, ETH_HLEN), &s->eh, ETH_HLEN);
345		break;
346
347	case BNEP_COMPRESSED_SRC_ONLY:
348		memcpy(__skb_put(nskb, ETH_ALEN), s->eh.h_dest, ETH_ALEN);
349		memcpy(__skb_put(nskb, ETH_ALEN), skb_mac_header(skb), ETH_ALEN);
350		put_unaligned(s->eh.h_proto, (__be16 *) __skb_put(nskb, 2));
351		break;
352
353	case BNEP_COMPRESSED_DST_ONLY:
354		memcpy(__skb_put(nskb, ETH_ALEN), skb_mac_header(skb),
355								ETH_ALEN);
356		memcpy(__skb_put(nskb, ETH_ALEN + 2), s->eh.h_source,
357								ETH_ALEN + 2);
358		break;
359
360	case BNEP_GENERAL:
361		memcpy(__skb_put(nskb, ETH_ALEN * 2), skb_mac_header(skb),
362								ETH_ALEN * 2);
363		put_unaligned(s->eh.h_proto, (__be16 *) __skb_put(nskb, 2));
364		break;
365	}
366
367	skb_copy_from_linear_data(skb, __skb_put(nskb, skb->len), skb->len);
368	kfree_skb(skb);
369
370	dev->stats.rx_packets++;
371	nskb->ip_summed = CHECKSUM_NONE;
372	nskb->protocol  = eth_type_trans(nskb, dev);
373	netif_rx_ni(nskb);
374	return 0;
375
376badframe:
377	dev->stats.rx_errors++;
378	kfree_skb(skb);
379	return 0;
380}
381
382static u8 __bnep_tx_types[] = {
383	BNEP_GENERAL,
384	BNEP_COMPRESSED_SRC_ONLY,
385	BNEP_COMPRESSED_DST_ONLY,
386	BNEP_COMPRESSED
387};
388
389static int bnep_tx_frame(struct bnep_session *s, struct sk_buff *skb)
390{
391	struct ethhdr *eh = (void *) skb->data;
392	struct socket *sock = s->sock;
393	struct kvec iv[3];
394	int len = 0, il = 0;
395	u8 type = 0;
396
397	BT_DBG("skb %p dev %p type %d", skb, skb->dev, skb->pkt_type);
398
399	if (!skb->dev) {
400		/* Control frame sent by us */
401		goto send;
402	}
403
404	iv[il++] = (struct kvec) { &type, 1 };
405	len++;
406
407	if (compress_src && ether_addr_equal(eh->h_dest, s->eh.h_source))
408		type |= 0x01;
409
410	if (compress_dst && ether_addr_equal(eh->h_source, s->eh.h_dest))
411		type |= 0x02;
412
413	if (type)
414		skb_pull(skb, ETH_ALEN * 2);
415
416	type = __bnep_tx_types[type];
417	switch (type) {
418	case BNEP_COMPRESSED_SRC_ONLY:
419		iv[il++] = (struct kvec) { eh->h_source, ETH_ALEN };
420		len += ETH_ALEN;
421		break;
422
423	case BNEP_COMPRESSED_DST_ONLY:
424		iv[il++] = (struct kvec) { eh->h_dest, ETH_ALEN };
425		len += ETH_ALEN;
426		break;
427	}
428
429send:
430	iv[il++] = (struct kvec) { skb->data, skb->len };
431	len += skb->len;
432
433	/* FIXME: linearize skb */
434	{
435		len = kernel_sendmsg(sock, &s->msg, iv, il, len);
436	}
437	kfree_skb(skb);
438
439	if (len > 0) {
440		s->dev->stats.tx_bytes += len;
441		s->dev->stats.tx_packets++;
442		return 0;
443	}
444
445	return len;
446}
447
448static int bnep_session(void *arg)
449{
450	struct bnep_session *s = arg;
451	struct net_device *dev = s->dev;
452	struct sock *sk = s->sock->sk;
453	struct sk_buff *skb;
454	wait_queue_t wait;
455
456	BT_DBG("");
457
458	set_user_nice(current, -15);
459
460	init_waitqueue_entry(&wait, current);
461	add_wait_queue(sk_sleep(sk), &wait);
462	while (1) {
463		set_current_state(TASK_INTERRUPTIBLE);
464
465		if (atomic_read(&s->terminate))
466			break;
467		/* RX */
468		while ((skb = skb_dequeue(&sk->sk_receive_queue))) {
469			skb_orphan(skb);
470			if (!skb_linearize(skb))
471				bnep_rx_frame(s, skb);
472			else
473				kfree_skb(skb);
474		}
475
476		if (sk->sk_state != BT_CONNECTED)
477			break;
478
479		/* TX */
480		while ((skb = skb_dequeue(&sk->sk_write_queue)))
481			if (bnep_tx_frame(s, skb))
482				break;
483		netif_wake_queue(dev);
484
485		schedule();
486	}
487	__set_current_state(TASK_RUNNING);
488	remove_wait_queue(sk_sleep(sk), &wait);
489
490	/* Cleanup session */
491	down_write(&bnep_session_sem);
492
493	/* Delete network device */
494	unregister_netdev(dev);
495
496	/* Wakeup user-space polling for socket errors */
497	s->sock->sk->sk_err = EUNATCH;
498
499	wake_up_interruptible(sk_sleep(s->sock->sk));
500
501	/* Release the socket */
502	fput(s->sock->file);
503
504	__bnep_unlink_session(s);
505
506	up_write(&bnep_session_sem);
507	free_netdev(dev);
508	module_put_and_exit(0);
509	return 0;
510}
511
512static struct device *bnep_get_device(struct bnep_session *session)
513{
 
 
 
514	struct hci_conn *conn;
515
516	conn = l2cap_pi(session->sock->sk)->chan->conn->hcon;
517	if (!conn)
518		return NULL;
519
520	return &conn->dev;
 
 
 
 
521}
522
523static struct device_type bnep_type = {
524	.name	= "bluetooth",
525};
526
527int bnep_add_connection(struct bnep_connadd_req *req, struct socket *sock)
528{
529	struct net_device *dev;
530	struct bnep_session *s, *ss;
531	u8 dst[ETH_ALEN], src[ETH_ALEN];
532	int err;
533
534	BT_DBG("");
535
536	baswap((void *) dst, &l2cap_pi(sock->sk)->chan->dst);
537	baswap((void *) src, &l2cap_pi(sock->sk)->chan->src);
538
539	/* session struct allocated as private part of net_device */
540	dev = alloc_netdev(sizeof(struct bnep_session),
541				(*req->device) ? req->device : "bnep%d",
542				bnep_net_setup);
543	if (!dev)
544		return -ENOMEM;
545
546	down_write(&bnep_session_sem);
547
548	ss = __bnep_get_session(dst);
549	if (ss && ss->state == BT_CONNECTED) {
550		err = -EEXIST;
551		goto failed;
552	}
553
554	s = netdev_priv(dev);
555
556	/* This is rx header therefore addresses are swapped.
557	 * ie. eh.h_dest is our local address. */
558	memcpy(s->eh.h_dest,   &src, ETH_ALEN);
559	memcpy(s->eh.h_source, &dst, ETH_ALEN);
560	memcpy(dev->dev_addr, s->eh.h_dest, ETH_ALEN);
561
562	s->dev   = dev;
563	s->sock  = sock;
564	s->role  = req->role;
565	s->state = BT_CONNECTED;
566
567	s->msg.msg_flags = MSG_NOSIGNAL;
568
569#ifdef CONFIG_BT_BNEP_MC_FILTER
570	/* Set default mc filter */
571	set_bit(bnep_mc_hash(dev->broadcast), (ulong *) &s->mc_filter);
572#endif
573
574#ifdef CONFIG_BT_BNEP_PROTO_FILTER
575	/* Set default protocol filter */
576	bnep_set_default_proto_filter(s);
577#endif
578
579	SET_NETDEV_DEV(dev, bnep_get_device(s));
580	SET_NETDEV_DEVTYPE(dev, &bnep_type);
581
582	err = register_netdev(dev);
583	if (err)
584		goto failed;
585
586	__bnep_link_session(s);
587
588	__module_get(THIS_MODULE);
589	s->task = kthread_run(bnep_session, s, "kbnepd %s", dev->name);
590	if (IS_ERR(s->task)) {
591		/* Session thread start failed, gotta cleanup. */
592		module_put(THIS_MODULE);
593		unregister_netdev(dev);
594		__bnep_unlink_session(s);
595		err = PTR_ERR(s->task);
596		goto failed;
597	}
598
599	up_write(&bnep_session_sem);
600	strcpy(req->device, dev->name);
601	return 0;
602
603failed:
604	up_write(&bnep_session_sem);
605	free_netdev(dev);
606	return err;
607}
608
609int bnep_del_connection(struct bnep_conndel_req *req)
610{
611	struct bnep_session *s;
612	int  err = 0;
613
614	BT_DBG("");
615
616	down_read(&bnep_session_sem);
617
618	s = __bnep_get_session(req->dst);
619	if (s) {
620		atomic_inc(&s->terminate);
621		wake_up_process(s->task);
622	} else
623		err = -ENOENT;
624
625	up_read(&bnep_session_sem);
626	return err;
627}
628
629static void __bnep_copy_ci(struct bnep_conninfo *ci, struct bnep_session *s)
630{
631	memset(ci, 0, sizeof(*ci));
632	memcpy(ci->dst, s->eh.h_source, ETH_ALEN);
633	strcpy(ci->device, s->dev->name);
634	ci->flags = s->flags;
635	ci->state = s->state;
636	ci->role  = s->role;
637}
638
639int bnep_get_connlist(struct bnep_connlist_req *req)
640{
641	struct bnep_session *s;
642	int err = 0, n = 0;
643
644	down_read(&bnep_session_sem);
645
646	list_for_each_entry(s, &bnep_session_list, list) {
647		struct bnep_conninfo ci;
648
649		__bnep_copy_ci(&ci, s);
650
651		if (copy_to_user(req->ci, &ci, sizeof(ci))) {
652			err = -EFAULT;
653			break;
654		}
655
656		if (++n >= req->cnum)
657			break;
658
659		req->ci++;
660	}
661	req->cnum = n;
662
663	up_read(&bnep_session_sem);
664	return err;
665}
666
667int bnep_get_conninfo(struct bnep_conninfo *ci)
668{
669	struct bnep_session *s;
670	int err = 0;
671
672	down_read(&bnep_session_sem);
673
674	s = __bnep_get_session(ci->dst);
675	if (s)
676		__bnep_copy_ci(ci, s);
677	else
678		err = -ENOENT;
679
680	up_read(&bnep_session_sem);
681	return err;
682}
683
684static int __init bnep_init(void)
685{
686	char flt[50] = "";
687
688#ifdef CONFIG_BT_BNEP_PROTO_FILTER
689	strcat(flt, "protocol ");
690#endif
691
692#ifdef CONFIG_BT_BNEP_MC_FILTER
693	strcat(flt, "multicast");
694#endif
695
696	BT_INFO("BNEP (Ethernet Emulation) ver %s", VERSION);
697	if (flt[0])
698		BT_INFO("BNEP filters: %s", flt);
699
700	bnep_sock_init();
701	return 0;
702}
703
704static void __exit bnep_exit(void)
705{
706	bnep_sock_cleanup();
707}
708
709module_init(bnep_init);
710module_exit(bnep_exit);
711
712module_param(compress_src, bool, 0644);
713MODULE_PARM_DESC(compress_src, "Compress sources headers");
714
715module_param(compress_dst, bool, 0644);
716MODULE_PARM_DESC(compress_dst, "Compress destination headers");
717
718MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
719MODULE_DESCRIPTION("Bluetooth BNEP ver " VERSION);
720MODULE_VERSION(VERSION);
721MODULE_LICENSE("GPL");
722MODULE_ALIAS("bt-proto-4");
v3.5.6
  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 <linux/slab.h>
 39#include <linux/kthread.h>
 40#include <net/sock.h>
 41
 42#include <linux/socket.h>
 43#include <linux/file.h>
 44
 45#include <linux/netdevice.h>
 46#include <linux/etherdevice.h>
 47#include <linux/skbuff.h>
 48
 49#include <asm/unaligned.h>
 50
 51#include <net/bluetooth/bluetooth.h>
 
 52#include <net/bluetooth/hci_core.h>
 53#include <net/bluetooth/l2cap.h>
 54
 55#include "bnep.h"
 56
 57#define VERSION "1.3"
 58
 59static bool compress_src = true;
 60static bool compress_dst = true;
 61
 62static LIST_HEAD(bnep_session_list);
 63static DECLARE_RWSEM(bnep_session_sem);
 64
 65static struct bnep_session *__bnep_get_session(u8 *dst)
 66{
 67	struct bnep_session *s;
 68
 69	BT_DBG("");
 70
 71	list_for_each_entry(s, &bnep_session_list, list)
 72		if (ether_addr_equal(dst, s->eh.h_source))
 73			return s;
 74
 75	return NULL;
 76}
 77
 78static void __bnep_link_session(struct bnep_session *s)
 79{
 80	list_add(&s->list, &bnep_session_list);
 81}
 82
 83static void __bnep_unlink_session(struct bnep_session *s)
 84{
 85	list_del(&s->list);
 86}
 87
 88static int bnep_send(struct bnep_session *s, void *data, size_t len)
 89{
 90	struct socket *sock = s->sock;
 91	struct kvec iv = { data, len };
 92
 93	return kernel_sendmsg(sock, &s->msg, &iv, 1, len);
 94}
 95
 96static int bnep_send_rsp(struct bnep_session *s, u8 ctrl, u16 resp)
 97{
 98	struct bnep_control_rsp rsp;
 99	rsp.type = BNEP_CONTROL;
100	rsp.ctrl = ctrl;
101	rsp.resp = htons(resp);
102	return bnep_send(s, &rsp, sizeof(rsp));
103}
104
105#ifdef CONFIG_BT_BNEP_PROTO_FILTER
106static inline void bnep_set_default_proto_filter(struct bnep_session *s)
107{
108	/* (IPv4, ARP)  */
109	s->proto_filter[0].start = ETH_P_IP;
110	s->proto_filter[0].end   = ETH_P_ARP;
111	/* (RARP, AppleTalk) */
112	s->proto_filter[1].start = ETH_P_RARP;
113	s->proto_filter[1].end   = ETH_P_AARP;
114	/* (IPX, IPv6) */
115	s->proto_filter[2].start = ETH_P_IPX;
116	s->proto_filter[2].end   = ETH_P_IPV6;
117}
118#endif
119
120static int bnep_ctrl_set_netfilter(struct bnep_session *s, __be16 *data, int len)
121{
122	int n;
123
124	if (len < 2)
125		return -EILSEQ;
126
127	n = get_unaligned_be16(data);
128	data++;
129	len -= 2;
130
131	if (len < n)
132		return -EILSEQ;
133
134	BT_DBG("filter len %d", n);
135
136#ifdef CONFIG_BT_BNEP_PROTO_FILTER
137	n /= 4;
138	if (n <= BNEP_MAX_PROTO_FILTERS) {
139		struct bnep_proto_filter *f = s->proto_filter;
140		int i;
141
142		for (i = 0; i < n; i++) {
143			f[i].start = get_unaligned_be16(data++);
144			f[i].end   = get_unaligned_be16(data++);
145
146			BT_DBG("proto filter start %d end %d",
147				f[i].start, f[i].end);
148		}
149
150		if (i < BNEP_MAX_PROTO_FILTERS)
151			memset(f + i, 0, sizeof(*f));
152
153		if (n == 0)
154			bnep_set_default_proto_filter(s);
155
156		bnep_send_rsp(s, BNEP_FILTER_NET_TYPE_RSP, BNEP_SUCCESS);
157	} else {
158		bnep_send_rsp(s, BNEP_FILTER_NET_TYPE_RSP, BNEP_FILTER_LIMIT_REACHED);
159	}
160#else
161	bnep_send_rsp(s, BNEP_FILTER_NET_TYPE_RSP, BNEP_FILTER_UNSUPPORTED_REQ);
162#endif
163	return 0;
164}
165
166static int bnep_ctrl_set_mcfilter(struct bnep_session *s, u8 *data, int len)
167{
168	int n;
169
170	if (len < 2)
171		return -EILSEQ;
172
173	n = get_unaligned_be16(data);
174	data += 2;
175	len -= 2;
176
177	if (len < n)
178		return -EILSEQ;
179
180	BT_DBG("filter len %d", n);
181
182#ifdef CONFIG_BT_BNEP_MC_FILTER
183	n /= (ETH_ALEN * 2);
184
185	if (n > 0) {
186		int i;
187
188		s->mc_filter = 0;
189
190		/* Always send broadcast */
191		set_bit(bnep_mc_hash(s->dev->broadcast), (ulong *) &s->mc_filter);
192
193		/* Add address ranges to the multicast hash */
194		for (; n > 0; n--) {
195			u8 a1[6], *a2;
196
197			memcpy(a1, data, ETH_ALEN);
198			data += ETH_ALEN;
199			a2 = data;
200			data += ETH_ALEN;
201
202			BT_DBG("mc filter %s -> %s",
203				batostr((void *) a1), batostr((void *) a2));
204
205			/* Iterate from a1 to a2 */
206			set_bit(bnep_mc_hash(a1), (ulong *) &s->mc_filter);
207			while (memcmp(a1, a2, 6) < 0 && s->mc_filter != ~0LL) {
208				/* Increment a1 */
209				i = 5;
210				while (i >= 0 && ++a1[i--] == 0)
211					;
212
213				set_bit(bnep_mc_hash(a1), (ulong *) &s->mc_filter);
214			}
215		}
216	}
217
218	BT_DBG("mc filter hash 0x%llx", s->mc_filter);
219
220	bnep_send_rsp(s, BNEP_FILTER_MULTI_ADDR_RSP, BNEP_SUCCESS);
221#else
222	bnep_send_rsp(s, BNEP_FILTER_MULTI_ADDR_RSP, BNEP_FILTER_UNSUPPORTED_REQ);
223#endif
224	return 0;
225}
226
227static int bnep_rx_control(struct bnep_session *s, void *data, int len)
228{
229	u8  cmd = *(u8 *)data;
230	int err = 0;
231
232	data++;
233	len--;
234
235	switch (cmd) {
236	case BNEP_CMD_NOT_UNDERSTOOD:
237	case BNEP_SETUP_CONN_RSP:
238	case BNEP_FILTER_NET_TYPE_RSP:
239	case BNEP_FILTER_MULTI_ADDR_RSP:
240		/* Ignore these for now */
241		break;
242
243	case BNEP_FILTER_NET_TYPE_SET:
244		err = bnep_ctrl_set_netfilter(s, data, len);
245		break;
246
247	case BNEP_FILTER_MULTI_ADDR_SET:
248		err = bnep_ctrl_set_mcfilter(s, data, len);
249		break;
250
251	case BNEP_SETUP_CONN_REQ:
252		err = bnep_send_rsp(s, BNEP_SETUP_CONN_RSP, BNEP_CONN_NOT_ALLOWED);
253		break;
254
255	default: {
256			u8 pkt[3];
257			pkt[0] = BNEP_CONTROL;
258			pkt[1] = BNEP_CMD_NOT_UNDERSTOOD;
259			pkt[2] = cmd;
260			bnep_send(s, pkt, sizeof(pkt));
261		}
262		break;
263	}
264
265	return err;
266}
267
268static int bnep_rx_extension(struct bnep_session *s, struct sk_buff *skb)
269{
270	struct bnep_ext_hdr *h;
271	int err = 0;
272
273	do {
274		h = (void *) skb->data;
275		if (!skb_pull(skb, sizeof(*h))) {
276			err = -EILSEQ;
277			break;
278		}
279
280		BT_DBG("type 0x%x len %d", h->type, h->len);
281
282		switch (h->type & BNEP_TYPE_MASK) {
283		case BNEP_EXT_CONTROL:
284			bnep_rx_control(s, skb->data, skb->len);
285			break;
286
287		default:
288			/* Unknown extension, skip it. */
289			break;
290		}
291
292		if (!skb_pull(skb, h->len)) {
293			err = -EILSEQ;
294			break;
295		}
296	} while (!err && (h->type & BNEP_EXT_HEADER));
297
298	return err;
299}
300
301static u8 __bnep_rx_hlen[] = {
302	ETH_HLEN,     /* BNEP_GENERAL */
303	0,            /* BNEP_CONTROL */
304	2,            /* BNEP_COMPRESSED */
305	ETH_ALEN + 2, /* BNEP_COMPRESSED_SRC_ONLY */
306	ETH_ALEN + 2  /* BNEP_COMPRESSED_DST_ONLY */
307};
308
309static 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->stats.rx_bytes += skb->len;
316
317	type = *(u8 *) skb->data;
318	skb_pull(skb, 1);
319
320	if ((type & BNEP_TYPE_MASK) >= sizeof(__bnep_rx_hlen))
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) == ETH_P_8021Q) {
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		dev->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	dev->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
394badframe:
395	dev->stats.rx_errors++;
396	kfree_skb(skb);
397	return 0;
398}
399
400static u8 __bnep_tx_types[] = {
401	BNEP_GENERAL,
402	BNEP_COMPRESSED_SRC_ONLY,
403	BNEP_COMPRESSED_DST_ONLY,
404	BNEP_COMPRESSED
405};
406
407static 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 (compress_src && ether_addr_equal(eh->h_dest, s->eh.h_source))
426		type |= 0x01;
427
428	if (compress_dst && ether_addr_equal(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
447send:
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->dev->stats.tx_bytes += len;
459		s->dev->stats.tx_packets++;
460		return 0;
461	}
462
463	return len;
464}
465
466static 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	set_user_nice(current, -15);
477
478	init_waitqueue_entry(&wait, current);
479	add_wait_queue(sk_sleep(sk), &wait);
480	while (1) {
481		set_current_state(TASK_INTERRUPTIBLE);
482
483		if (atomic_read(&s->terminate))
484			break;
485		/* RX */
486		while ((skb = skb_dequeue(&sk->sk_receive_queue))) {
487			skb_orphan(skb);
488			if (!skb_linearize(skb))
489				bnep_rx_frame(s, skb);
490			else
491				kfree_skb(skb);
492		}
493
494		if (sk->sk_state != BT_CONNECTED)
495			break;
496
497		/* TX */
498		while ((skb = skb_dequeue(&sk->sk_write_queue)))
499			if (bnep_tx_frame(s, skb))
500				break;
501		netif_wake_queue(dev);
502
503		schedule();
504	}
505	__set_current_state(TASK_RUNNING);
506	remove_wait_queue(sk_sleep(sk), &wait);
507
508	/* Cleanup session */
509	down_write(&bnep_session_sem);
510
511	/* Delete network device */
512	unregister_netdev(dev);
513
514	/* Wakeup user-space polling for socket errors */
515	s->sock->sk->sk_err = EUNATCH;
516
517	wake_up_interruptible(sk_sleep(s->sock->sk));
518
519	/* Release the socket */
520	fput(s->sock->file);
521
522	__bnep_unlink_session(s);
523
524	up_write(&bnep_session_sem);
525	free_netdev(dev);
526	module_put_and_exit(0);
527	return 0;
528}
529
530static struct device *bnep_get_device(struct bnep_session *session)
531{
532	bdaddr_t *src = &bt_sk(session->sock->sk)->src;
533	bdaddr_t *dst = &bt_sk(session->sock->sk)->dst;
534	struct hci_dev *hdev;
535	struct hci_conn *conn;
536
537	hdev = hci_get_route(dst, src);
538	if (!hdev)
539		return NULL;
540
541	conn = hci_conn_hash_lookup_ba(hdev, ACL_LINK, dst);
542
543	hci_dev_put(hdev);
544
545	return conn ? &conn->dev : NULL;
546}
547
548static struct device_type bnep_type = {
549	.name	= "bluetooth",
550};
551
552int bnep_add_connection(struct bnep_connadd_req *req, struct socket *sock)
553{
554	struct net_device *dev;
555	struct bnep_session *s, *ss;
556	u8 dst[ETH_ALEN], src[ETH_ALEN];
557	int err;
558
559	BT_DBG("");
560
561	baswap((void *) dst, &bt_sk(sock->sk)->dst);
562	baswap((void *) src, &bt_sk(sock->sk)->src);
563
564	/* session struct allocated as private part of net_device */
565	dev = alloc_netdev(sizeof(struct bnep_session),
566				(*req->device) ? req->device : "bnep%d",
567				bnep_net_setup);
568	if (!dev)
569		return -ENOMEM;
570
571	down_write(&bnep_session_sem);
572
573	ss = __bnep_get_session(dst);
574	if (ss && ss->state == BT_CONNECTED) {
575		err = -EEXIST;
576		goto failed;
577	}
578
579	s = netdev_priv(dev);
580
581	/* This is rx header therefore addresses are swapped.
582	 * ie. eh.h_dest is our local address. */
583	memcpy(s->eh.h_dest,   &src, ETH_ALEN);
584	memcpy(s->eh.h_source, &dst, ETH_ALEN);
585	memcpy(dev->dev_addr, s->eh.h_dest, ETH_ALEN);
586
587	s->dev   = dev;
588	s->sock  = sock;
589	s->role  = req->role;
590	s->state = BT_CONNECTED;
591
592	s->msg.msg_flags = MSG_NOSIGNAL;
593
594#ifdef CONFIG_BT_BNEP_MC_FILTER
595	/* Set default mc filter */
596	set_bit(bnep_mc_hash(dev->broadcast), (ulong *) &s->mc_filter);
597#endif
598
599#ifdef CONFIG_BT_BNEP_PROTO_FILTER
600	/* Set default protocol filter */
601	bnep_set_default_proto_filter(s);
602#endif
603
604	SET_NETDEV_DEV(dev, bnep_get_device(s));
605	SET_NETDEV_DEVTYPE(dev, &bnep_type);
606
607	err = register_netdev(dev);
608	if (err)
609		goto failed;
610
611	__bnep_link_session(s);
612
613	__module_get(THIS_MODULE);
614	s->task = kthread_run(bnep_session, s, "kbnepd %s", dev->name);
615	if (IS_ERR(s->task)) {
616		/* Session thread start failed, gotta cleanup. */
617		module_put(THIS_MODULE);
618		unregister_netdev(dev);
619		__bnep_unlink_session(s);
620		err = PTR_ERR(s->task);
621		goto failed;
622	}
623
624	up_write(&bnep_session_sem);
625	strcpy(req->device, dev->name);
626	return 0;
627
628failed:
629	up_write(&bnep_session_sem);
630	free_netdev(dev);
631	return err;
632}
633
634int bnep_del_connection(struct bnep_conndel_req *req)
635{
636	struct bnep_session *s;
637	int  err = 0;
638
639	BT_DBG("");
640
641	down_read(&bnep_session_sem);
642
643	s = __bnep_get_session(req->dst);
644	if (s) {
645		atomic_inc(&s->terminate);
646		wake_up_process(s->task);
647	} else
648		err = -ENOENT;
649
650	up_read(&bnep_session_sem);
651	return err;
652}
653
654static void __bnep_copy_ci(struct bnep_conninfo *ci, struct bnep_session *s)
655{
656	memset(ci, 0, sizeof(*ci));
657	memcpy(ci->dst, s->eh.h_source, ETH_ALEN);
658	strcpy(ci->device, s->dev->name);
659	ci->flags = s->flags;
660	ci->state = s->state;
661	ci->role  = s->role;
662}
663
664int bnep_get_connlist(struct bnep_connlist_req *req)
665{
666	struct bnep_session *s;
667	int err = 0, n = 0;
668
669	down_read(&bnep_session_sem);
670
671	list_for_each_entry(s, &bnep_session_list, list) {
672		struct bnep_conninfo ci;
673
674		__bnep_copy_ci(&ci, s);
675
676		if (copy_to_user(req->ci, &ci, sizeof(ci))) {
677			err = -EFAULT;
678			break;
679		}
680
681		if (++n >= req->cnum)
682			break;
683
684		req->ci++;
685	}
686	req->cnum = n;
687
688	up_read(&bnep_session_sem);
689	return err;
690}
691
692int bnep_get_conninfo(struct bnep_conninfo *ci)
693{
694	struct bnep_session *s;
695	int err = 0;
696
697	down_read(&bnep_session_sem);
698
699	s = __bnep_get_session(ci->dst);
700	if (s)
701		__bnep_copy_ci(ci, s);
702	else
703		err = -ENOENT;
704
705	up_read(&bnep_session_sem);
706	return err;
707}
708
709static int __init bnep_init(void)
710{
711	char flt[50] = "";
712
713#ifdef CONFIG_BT_BNEP_PROTO_FILTER
714	strcat(flt, "protocol ");
715#endif
716
717#ifdef CONFIG_BT_BNEP_MC_FILTER
718	strcat(flt, "multicast");
719#endif
720
721	BT_INFO("BNEP (Ethernet Emulation) ver %s", VERSION);
722	if (flt[0])
723		BT_INFO("BNEP filters: %s", flt);
724
725	bnep_sock_init();
726	return 0;
727}
728
729static void __exit bnep_exit(void)
730{
731	bnep_sock_cleanup();
732}
733
734module_init(bnep_init);
735module_exit(bnep_exit);
736
737module_param(compress_src, bool, 0644);
738MODULE_PARM_DESC(compress_src, "Compress sources headers");
739
740module_param(compress_dst, bool, 0644);
741MODULE_PARM_DESC(compress_dst, "Compress destination headers");
742
743MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
744MODULE_DESCRIPTION("Bluetooth BNEP ver " VERSION);
745MODULE_VERSION(VERSION);
746MODULE_LICENSE("GPL");
747MODULE_ALIAS("bt-proto-4");