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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 Copyright (c) 2013-2014 Intel Corp.
4
5*/
6
7#include <linux/if_arp.h>
8#include <linux/netdevice.h>
9#include <linux/etherdevice.h>
10#include <linux/module.h>
11#include <linux/debugfs.h>
12
13#include <net/ipv6.h>
14#include <net/ip6_route.h>
15#include <net/addrconf.h>
16#include <net/pkt_sched.h>
17
18#include <net/bluetooth/bluetooth.h>
19#include <net/bluetooth/hci_core.h>
20#include <net/bluetooth/l2cap.h>
21
22#include <net/6lowpan.h> /* for the compression support */
23
24#define VERSION "0.1"
25
26static struct dentry *lowpan_enable_debugfs;
27static struct dentry *lowpan_control_debugfs;
28
29#define IFACE_NAME_TEMPLATE "bt%d"
30
31struct skb_cb {
32 struct in6_addr addr;
33 struct in6_addr gw;
34 struct l2cap_chan *chan;
35};
36#define lowpan_cb(skb) ((struct skb_cb *)((skb)->cb))
37
38/* The devices list contains those devices that we are acting
39 * as a proxy. The BT 6LoWPAN device is a virtual device that
40 * connects to the Bluetooth LE device. The real connection to
41 * BT device is done via l2cap layer. There exists one
42 * virtual device / one BT 6LoWPAN network (=hciX device).
43 * The list contains struct lowpan_dev elements.
44 */
45static LIST_HEAD(bt_6lowpan_devices);
46static DEFINE_SPINLOCK(devices_lock);
47
48static bool enable_6lowpan;
49
50/* We are listening incoming connections via this channel
51 */
52static struct l2cap_chan *listen_chan;
53static DEFINE_MUTEX(set_lock);
54
55struct lowpan_peer {
56 struct list_head list;
57 struct rcu_head rcu;
58 struct l2cap_chan *chan;
59
60 /* peer addresses in various formats */
61 unsigned char lladdr[ETH_ALEN];
62 struct in6_addr peer_addr;
63};
64
65struct lowpan_btle_dev {
66 struct list_head list;
67
68 struct hci_dev *hdev;
69 struct net_device *netdev;
70 struct list_head peers;
71 atomic_t peer_count; /* number of items in peers list */
72
73 struct work_struct delete_netdev;
74 struct delayed_work notify_peers;
75};
76
77static inline struct lowpan_btle_dev *
78lowpan_btle_dev(const struct net_device *netdev)
79{
80 return (struct lowpan_btle_dev *)lowpan_dev(netdev)->priv;
81}
82
83static inline void peer_add(struct lowpan_btle_dev *dev,
84 struct lowpan_peer *peer)
85{
86 list_add_rcu(&peer->list, &dev->peers);
87 atomic_inc(&dev->peer_count);
88}
89
90static inline bool peer_del(struct lowpan_btle_dev *dev,
91 struct lowpan_peer *peer)
92{
93 list_del_rcu(&peer->list);
94 kfree_rcu(peer, rcu);
95
96 module_put(THIS_MODULE);
97
98 if (atomic_dec_and_test(&dev->peer_count)) {
99 BT_DBG("last peer");
100 return true;
101 }
102
103 return false;
104}
105
106static inline struct lowpan_peer *
107__peer_lookup_chan(struct lowpan_btle_dev *dev, struct l2cap_chan *chan)
108{
109 struct lowpan_peer *peer;
110
111 list_for_each_entry_rcu(peer, &dev->peers, list) {
112 if (peer->chan == chan)
113 return peer;
114 }
115
116 return NULL;
117}
118
119static inline struct lowpan_peer *
120__peer_lookup_conn(struct lowpan_btle_dev *dev, struct l2cap_conn *conn)
121{
122 struct lowpan_peer *peer;
123
124 list_for_each_entry_rcu(peer, &dev->peers, list) {
125 if (peer->chan->conn == conn)
126 return peer;
127 }
128
129 return NULL;
130}
131
132static inline struct lowpan_peer *peer_lookup_dst(struct lowpan_btle_dev *dev,
133 struct in6_addr *daddr,
134 struct sk_buff *skb)
135{
136 struct rt6_info *rt = dst_rt6_info(skb_dst(skb));
137 int count = atomic_read(&dev->peer_count);
138 const struct in6_addr *nexthop;
139 struct lowpan_peer *peer;
140 struct neighbour *neigh;
141
142 BT_DBG("peers %d addr %pI6c rt %p", count, daddr, rt);
143
144 if (!rt) {
145 if (ipv6_addr_any(&lowpan_cb(skb)->gw)) {
146 /* There is neither route nor gateway,
147 * probably the destination is a direct peer.
148 */
149 nexthop = daddr;
150 } else {
151 /* There is a known gateway
152 */
153 nexthop = &lowpan_cb(skb)->gw;
154 }
155 } else {
156 nexthop = rt6_nexthop(rt, daddr);
157
158 /* We need to remember the address because it is needed
159 * by bt_xmit() when sending the packet. In bt_xmit(), the
160 * destination routing info is not set.
161 */
162 memcpy(&lowpan_cb(skb)->gw, nexthop, sizeof(struct in6_addr));
163 }
164
165 BT_DBG("gw %pI6c", nexthop);
166
167 rcu_read_lock();
168
169 list_for_each_entry_rcu(peer, &dev->peers, list) {
170 BT_DBG("dst addr %pMR dst type %u ip %pI6c",
171 &peer->chan->dst, peer->chan->dst_type,
172 &peer->peer_addr);
173
174 if (!ipv6_addr_cmp(&peer->peer_addr, nexthop)) {
175 rcu_read_unlock();
176 return peer;
177 }
178 }
179
180 /* use the neighbour cache for matching addresses assigned by SLAAC */
181 neigh = __ipv6_neigh_lookup(dev->netdev, nexthop);
182 if (neigh) {
183 list_for_each_entry_rcu(peer, &dev->peers, list) {
184 if (!memcmp(neigh->ha, peer->lladdr, ETH_ALEN)) {
185 neigh_release(neigh);
186 rcu_read_unlock();
187 return peer;
188 }
189 }
190 neigh_release(neigh);
191 }
192
193 rcu_read_unlock();
194
195 return NULL;
196}
197
198static struct lowpan_peer *lookup_peer(struct l2cap_conn *conn)
199{
200 struct lowpan_btle_dev *entry;
201 struct lowpan_peer *peer = NULL;
202
203 rcu_read_lock();
204
205 list_for_each_entry_rcu(entry, &bt_6lowpan_devices, list) {
206 peer = __peer_lookup_conn(entry, conn);
207 if (peer)
208 break;
209 }
210
211 rcu_read_unlock();
212
213 return peer;
214}
215
216static struct lowpan_btle_dev *lookup_dev(struct l2cap_conn *conn)
217{
218 struct lowpan_btle_dev *entry;
219 struct lowpan_btle_dev *dev = NULL;
220
221 rcu_read_lock();
222
223 list_for_each_entry_rcu(entry, &bt_6lowpan_devices, list) {
224 if (conn->hcon->hdev == entry->hdev) {
225 dev = entry;
226 break;
227 }
228 }
229
230 rcu_read_unlock();
231
232 return dev;
233}
234
235static int give_skb_to_upper(struct sk_buff *skb, struct net_device *dev)
236{
237 struct sk_buff *skb_cp;
238
239 skb_cp = skb_copy(skb, GFP_ATOMIC);
240 if (!skb_cp)
241 return NET_RX_DROP;
242
243 return netif_rx(skb_cp);
244}
245
246static int iphc_decompress(struct sk_buff *skb, struct net_device *netdev,
247 struct lowpan_peer *peer)
248{
249 const u8 *saddr;
250
251 saddr = peer->lladdr;
252
253 return lowpan_header_decompress(skb, netdev, netdev->dev_addr, saddr);
254}
255
256static int recv_pkt(struct sk_buff *skb, struct net_device *dev,
257 struct lowpan_peer *peer)
258{
259 struct sk_buff *local_skb;
260 int ret;
261
262 if (!netif_running(dev))
263 goto drop;
264
265 if (dev->type != ARPHRD_6LOWPAN || !skb->len)
266 goto drop;
267
268 skb_reset_network_header(skb);
269
270 skb = skb_share_check(skb, GFP_ATOMIC);
271 if (!skb)
272 goto drop;
273
274 /* check that it's our buffer */
275 if (lowpan_is_ipv6(*skb_network_header(skb))) {
276 /* Pull off the 1-byte of 6lowpan header. */
277 skb_pull(skb, 1);
278
279 /* Copy the packet so that the IPv6 header is
280 * properly aligned.
281 */
282 local_skb = skb_copy_expand(skb, NET_SKB_PAD - 1,
283 skb_tailroom(skb), GFP_ATOMIC);
284 if (!local_skb)
285 goto drop;
286
287 local_skb->protocol = htons(ETH_P_IPV6);
288 local_skb->pkt_type = PACKET_HOST;
289 local_skb->dev = dev;
290
291 skb_set_transport_header(local_skb, sizeof(struct ipv6hdr));
292
293 if (give_skb_to_upper(local_skb, dev) != NET_RX_SUCCESS) {
294 kfree_skb(local_skb);
295 goto drop;
296 }
297
298 dev->stats.rx_bytes += skb->len;
299 dev->stats.rx_packets++;
300
301 consume_skb(local_skb);
302 consume_skb(skb);
303 } else if (lowpan_is_iphc(*skb_network_header(skb))) {
304 local_skb = skb_clone(skb, GFP_ATOMIC);
305 if (!local_skb)
306 goto drop;
307
308 local_skb->dev = dev;
309
310 ret = iphc_decompress(local_skb, dev, peer);
311 if (ret < 0) {
312 BT_DBG("iphc_decompress failed: %d", ret);
313 kfree_skb(local_skb);
314 goto drop;
315 }
316
317 local_skb->protocol = htons(ETH_P_IPV6);
318 local_skb->pkt_type = PACKET_HOST;
319
320 if (give_skb_to_upper(local_skb, dev)
321 != NET_RX_SUCCESS) {
322 kfree_skb(local_skb);
323 goto drop;
324 }
325
326 dev->stats.rx_bytes += skb->len;
327 dev->stats.rx_packets++;
328
329 consume_skb(local_skb);
330 consume_skb(skb);
331 } else {
332 BT_DBG("unknown packet type");
333 goto drop;
334 }
335
336 return NET_RX_SUCCESS;
337
338drop:
339 dev->stats.rx_dropped++;
340 return NET_RX_DROP;
341}
342
343/* Packet from BT LE device */
344static int chan_recv_cb(struct l2cap_chan *chan, struct sk_buff *skb)
345{
346 struct lowpan_btle_dev *dev;
347 struct lowpan_peer *peer;
348 int err;
349
350 peer = lookup_peer(chan->conn);
351 if (!peer)
352 return -ENOENT;
353
354 dev = lookup_dev(chan->conn);
355 if (!dev || !dev->netdev)
356 return -ENOENT;
357
358 err = recv_pkt(skb, dev->netdev, peer);
359 if (err) {
360 BT_DBG("recv pkt %d", err);
361 err = -EAGAIN;
362 }
363
364 return err;
365}
366
367static int setup_header(struct sk_buff *skb, struct net_device *netdev,
368 bdaddr_t *peer_addr, u8 *peer_addr_type)
369{
370 struct in6_addr ipv6_daddr;
371 struct ipv6hdr *hdr;
372 struct lowpan_btle_dev *dev;
373 struct lowpan_peer *peer;
374 u8 *daddr;
375 int err, status = 0;
376
377 hdr = ipv6_hdr(skb);
378
379 dev = lowpan_btle_dev(netdev);
380
381 memcpy(&ipv6_daddr, &hdr->daddr, sizeof(ipv6_daddr));
382
383 if (ipv6_addr_is_multicast(&ipv6_daddr)) {
384 lowpan_cb(skb)->chan = NULL;
385 daddr = NULL;
386 } else {
387 BT_DBG("dest IP %pI6c", &ipv6_daddr);
388
389 /* The packet might be sent to 6lowpan interface
390 * because of routing (either via default route
391 * or user set route) so get peer according to
392 * the destination address.
393 */
394 peer = peer_lookup_dst(dev, &ipv6_daddr, skb);
395 if (!peer) {
396 BT_DBG("no such peer");
397 return -ENOENT;
398 }
399
400 daddr = peer->lladdr;
401 *peer_addr = peer->chan->dst;
402 *peer_addr_type = peer->chan->dst_type;
403 lowpan_cb(skb)->chan = peer->chan;
404
405 status = 1;
406 }
407
408 lowpan_header_compress(skb, netdev, daddr, dev->netdev->dev_addr);
409
410 err = dev_hard_header(skb, netdev, ETH_P_IPV6, NULL, NULL, 0);
411 if (err < 0)
412 return err;
413
414 return status;
415}
416
417static int header_create(struct sk_buff *skb, struct net_device *netdev,
418 unsigned short type, const void *_daddr,
419 const void *_saddr, unsigned int len)
420{
421 if (type != ETH_P_IPV6)
422 return -EINVAL;
423
424 return 0;
425}
426
427/* Packet to BT LE device */
428static int send_pkt(struct l2cap_chan *chan, struct sk_buff *skb,
429 struct net_device *netdev)
430{
431 struct msghdr msg;
432 struct kvec iv;
433 int err;
434
435 /* Remember the skb so that we can send EAGAIN to the caller if
436 * we run out of credits.
437 */
438 chan->data = skb;
439
440 iv.iov_base = skb->data;
441 iv.iov_len = skb->len;
442
443 memset(&msg, 0, sizeof(msg));
444 iov_iter_kvec(&msg.msg_iter, ITER_SOURCE, &iv, 1, skb->len);
445
446 err = l2cap_chan_send(chan, &msg, skb->len);
447 if (err > 0) {
448 netdev->stats.tx_bytes += err;
449 netdev->stats.tx_packets++;
450 return 0;
451 }
452
453 if (err < 0)
454 netdev->stats.tx_errors++;
455
456 return err;
457}
458
459static int send_mcast_pkt(struct sk_buff *skb, struct net_device *netdev)
460{
461 struct sk_buff *local_skb;
462 struct lowpan_btle_dev *entry;
463 int err = 0;
464
465 rcu_read_lock();
466
467 list_for_each_entry_rcu(entry, &bt_6lowpan_devices, list) {
468 struct lowpan_peer *pentry;
469 struct lowpan_btle_dev *dev;
470
471 if (entry->netdev != netdev)
472 continue;
473
474 dev = lowpan_btle_dev(entry->netdev);
475
476 list_for_each_entry_rcu(pentry, &dev->peers, list) {
477 int ret;
478
479 local_skb = skb_clone(skb, GFP_ATOMIC);
480
481 BT_DBG("xmit %s to %pMR type %u IP %pI6c chan %p",
482 netdev->name,
483 &pentry->chan->dst, pentry->chan->dst_type,
484 &pentry->peer_addr, pentry->chan);
485 ret = send_pkt(pentry->chan, local_skb, netdev);
486 if (ret < 0)
487 err = ret;
488
489 kfree_skb(local_skb);
490 }
491 }
492
493 rcu_read_unlock();
494
495 return err;
496}
497
498static netdev_tx_t bt_xmit(struct sk_buff *skb, struct net_device *netdev)
499{
500 int err = 0;
501 bdaddr_t addr;
502 u8 addr_type;
503
504 /* We must take a copy of the skb before we modify/replace the ipv6
505 * header as the header could be used elsewhere
506 */
507 skb = skb_unshare(skb, GFP_ATOMIC);
508 if (!skb)
509 return NET_XMIT_DROP;
510
511 /* Return values from setup_header()
512 * <0 - error, packet is dropped
513 * 0 - this is a multicast packet
514 * 1 - this is unicast packet
515 */
516 err = setup_header(skb, netdev, &addr, &addr_type);
517 if (err < 0) {
518 kfree_skb(skb);
519 return NET_XMIT_DROP;
520 }
521
522 if (err) {
523 if (lowpan_cb(skb)->chan) {
524 BT_DBG("xmit %s to %pMR type %u IP %pI6c chan %p",
525 netdev->name, &addr, addr_type,
526 &lowpan_cb(skb)->addr, lowpan_cb(skb)->chan);
527 err = send_pkt(lowpan_cb(skb)->chan, skb, netdev);
528 } else {
529 err = -ENOENT;
530 }
531 } else {
532 /* We need to send the packet to every device behind this
533 * interface.
534 */
535 err = send_mcast_pkt(skb, netdev);
536 }
537
538 dev_kfree_skb(skb);
539
540 if (err)
541 BT_DBG("ERROR: xmit failed (%d)", err);
542
543 return err < 0 ? NET_XMIT_DROP : err;
544}
545
546static int bt_dev_init(struct net_device *dev)
547{
548 netdev_lockdep_set_classes(dev);
549
550 return 0;
551}
552
553static const struct net_device_ops netdev_ops = {
554 .ndo_init = bt_dev_init,
555 .ndo_start_xmit = bt_xmit,
556};
557
558static const struct header_ops header_ops = {
559 .create = header_create,
560};
561
562static void netdev_setup(struct net_device *dev)
563{
564 dev->hard_header_len = 0;
565 dev->needed_tailroom = 0;
566 dev->flags = IFF_RUNNING | IFF_MULTICAST;
567 dev->watchdog_timeo = 0;
568 dev->tx_queue_len = DEFAULT_TX_QUEUE_LEN;
569
570 dev->netdev_ops = &netdev_ops;
571 dev->header_ops = &header_ops;
572 dev->needs_free_netdev = true;
573}
574
575static const struct device_type bt_type = {
576 .name = "bluetooth",
577};
578
579static void ifup(struct net_device *netdev)
580{
581 int err;
582
583 rtnl_lock();
584 err = dev_open(netdev, NULL);
585 if (err < 0)
586 BT_INFO("iface %s cannot be opened (%d)", netdev->name, err);
587 rtnl_unlock();
588}
589
590static void ifdown(struct net_device *netdev)
591{
592 rtnl_lock();
593 dev_close(netdev);
594 rtnl_unlock();
595}
596
597static void do_notify_peers(struct work_struct *work)
598{
599 struct lowpan_btle_dev *dev = container_of(work, struct lowpan_btle_dev,
600 notify_peers.work);
601
602 netdev_notify_peers(dev->netdev); /* send neighbour adv at startup */
603}
604
605static bool is_bt_6lowpan(struct hci_conn *hcon)
606{
607 if (hcon->type != LE_LINK)
608 return false;
609
610 if (!enable_6lowpan)
611 return false;
612
613 return true;
614}
615
616static struct l2cap_chan *chan_create(void)
617{
618 struct l2cap_chan *chan;
619
620 chan = l2cap_chan_create();
621 if (!chan)
622 return NULL;
623
624 l2cap_chan_set_defaults(chan);
625
626 chan->chan_type = L2CAP_CHAN_CONN_ORIENTED;
627 chan->mode = L2CAP_MODE_LE_FLOWCTL;
628 chan->imtu = 1280;
629
630 return chan;
631}
632
633static struct l2cap_chan *add_peer_chan(struct l2cap_chan *chan,
634 struct lowpan_btle_dev *dev,
635 bool new_netdev)
636{
637 struct lowpan_peer *peer;
638
639 peer = kzalloc(sizeof(*peer), GFP_ATOMIC);
640 if (!peer)
641 return NULL;
642
643 peer->chan = chan;
644
645 baswap((void *)peer->lladdr, &chan->dst);
646
647 lowpan_iphc_uncompress_eui48_lladdr(&peer->peer_addr, peer->lladdr);
648
649 spin_lock(&devices_lock);
650 INIT_LIST_HEAD(&peer->list);
651 peer_add(dev, peer);
652 spin_unlock(&devices_lock);
653
654 /* Notifying peers about us needs to be done without locks held */
655 if (new_netdev)
656 INIT_DELAYED_WORK(&dev->notify_peers, do_notify_peers);
657 schedule_delayed_work(&dev->notify_peers, msecs_to_jiffies(100));
658
659 return peer->chan;
660}
661
662static int setup_netdev(struct l2cap_chan *chan, struct lowpan_btle_dev **dev)
663{
664 struct net_device *netdev;
665 bdaddr_t addr;
666 int err;
667
668 netdev = alloc_netdev(LOWPAN_PRIV_SIZE(sizeof(struct lowpan_btle_dev)),
669 IFACE_NAME_TEMPLATE, NET_NAME_UNKNOWN,
670 netdev_setup);
671 if (!netdev)
672 return -ENOMEM;
673
674 netdev->addr_assign_type = NET_ADDR_PERM;
675 baswap(&addr, &chan->src);
676 __dev_addr_set(netdev, &addr, sizeof(addr));
677
678 netdev->netdev_ops = &netdev_ops;
679 SET_NETDEV_DEV(netdev, &chan->conn->hcon->hdev->dev);
680 SET_NETDEV_DEVTYPE(netdev, &bt_type);
681
682 *dev = lowpan_btle_dev(netdev);
683 (*dev)->netdev = netdev;
684 (*dev)->hdev = chan->conn->hcon->hdev;
685 INIT_LIST_HEAD(&(*dev)->peers);
686
687 spin_lock(&devices_lock);
688 INIT_LIST_HEAD(&(*dev)->list);
689 list_add_rcu(&(*dev)->list, &bt_6lowpan_devices);
690 spin_unlock(&devices_lock);
691
692 err = lowpan_register_netdev(netdev, LOWPAN_LLTYPE_BTLE);
693 if (err < 0) {
694 BT_INFO("register_netdev failed %d", err);
695 spin_lock(&devices_lock);
696 list_del_rcu(&(*dev)->list);
697 spin_unlock(&devices_lock);
698 free_netdev(netdev);
699 goto out;
700 }
701
702 BT_DBG("ifindex %d peer bdaddr %pMR type %d my addr %pMR type %d",
703 netdev->ifindex, &chan->dst, chan->dst_type,
704 &chan->src, chan->src_type);
705 set_bit(__LINK_STATE_PRESENT, &netdev->state);
706
707 return 0;
708
709out:
710 return err;
711}
712
713static inline void chan_ready_cb(struct l2cap_chan *chan)
714{
715 struct lowpan_btle_dev *dev;
716 bool new_netdev = false;
717
718 dev = lookup_dev(chan->conn);
719
720 BT_DBG("chan %p conn %p dev %p", chan, chan->conn, dev);
721
722 if (!dev) {
723 if (setup_netdev(chan, &dev) < 0) {
724 l2cap_chan_del(chan, -ENOENT);
725 return;
726 }
727 new_netdev = true;
728 }
729
730 if (!try_module_get(THIS_MODULE))
731 return;
732
733 add_peer_chan(chan, dev, new_netdev);
734 ifup(dev->netdev);
735}
736
737static inline struct l2cap_chan *chan_new_conn_cb(struct l2cap_chan *pchan)
738{
739 struct l2cap_chan *chan;
740
741 chan = chan_create();
742 if (!chan)
743 return NULL;
744
745 chan->ops = pchan->ops;
746
747 BT_DBG("chan %p pchan %p", chan, pchan);
748
749 return chan;
750}
751
752static void delete_netdev(struct work_struct *work)
753{
754 struct lowpan_btle_dev *entry = container_of(work,
755 struct lowpan_btle_dev,
756 delete_netdev);
757
758 lowpan_unregister_netdev(entry->netdev);
759
760 /* The entry pointer is deleted by the netdev destructor. */
761}
762
763static void chan_close_cb(struct l2cap_chan *chan)
764{
765 struct lowpan_btle_dev *entry;
766 struct lowpan_btle_dev *dev = NULL;
767 struct lowpan_peer *peer;
768 int err = -ENOENT;
769 bool last = false, remove = true;
770
771 BT_DBG("chan %p conn %p", chan, chan->conn);
772
773 if (chan->conn && chan->conn->hcon) {
774 if (!is_bt_6lowpan(chan->conn->hcon))
775 return;
776
777 /* If conn is set, then the netdev is also there and we should
778 * not remove it.
779 */
780 remove = false;
781 }
782
783 spin_lock(&devices_lock);
784
785 list_for_each_entry_rcu(entry, &bt_6lowpan_devices, list) {
786 dev = lowpan_btle_dev(entry->netdev);
787 peer = __peer_lookup_chan(dev, chan);
788 if (peer) {
789 last = peer_del(dev, peer);
790 err = 0;
791
792 BT_DBG("dev %p removing %speer %p", dev,
793 last ? "last " : "1 ", peer);
794 BT_DBG("chan %p orig refcnt %u", chan,
795 kref_read(&chan->kref));
796
797 l2cap_chan_put(chan);
798 break;
799 }
800 }
801
802 if (!err && last && dev && !atomic_read(&dev->peer_count)) {
803 spin_unlock(&devices_lock);
804
805 cancel_delayed_work_sync(&dev->notify_peers);
806
807 ifdown(dev->netdev);
808
809 if (remove) {
810 INIT_WORK(&entry->delete_netdev, delete_netdev);
811 schedule_work(&entry->delete_netdev);
812 }
813 } else {
814 spin_unlock(&devices_lock);
815 }
816}
817
818static void chan_state_change_cb(struct l2cap_chan *chan, int state, int err)
819{
820 BT_DBG("chan %p conn %p state %s err %d", chan, chan->conn,
821 state_to_string(state), err);
822}
823
824static struct sk_buff *chan_alloc_skb_cb(struct l2cap_chan *chan,
825 unsigned long hdr_len,
826 unsigned long len, int nb)
827{
828 /* Note that we must allocate using GFP_ATOMIC here as
829 * this function is called originally from netdev hard xmit
830 * function in atomic context.
831 */
832 return bt_skb_alloc(hdr_len + len, GFP_ATOMIC);
833}
834
835static void chan_suspend_cb(struct l2cap_chan *chan)
836{
837 struct lowpan_btle_dev *dev;
838
839 BT_DBG("chan %p suspend", chan);
840
841 dev = lookup_dev(chan->conn);
842 if (!dev || !dev->netdev)
843 return;
844
845 netif_stop_queue(dev->netdev);
846}
847
848static void chan_resume_cb(struct l2cap_chan *chan)
849{
850 struct lowpan_btle_dev *dev;
851
852 BT_DBG("chan %p resume", chan);
853
854 dev = lookup_dev(chan->conn);
855 if (!dev || !dev->netdev)
856 return;
857
858 netif_wake_queue(dev->netdev);
859}
860
861static long chan_get_sndtimeo_cb(struct l2cap_chan *chan)
862{
863 return L2CAP_CONN_TIMEOUT;
864}
865
866static const struct l2cap_ops bt_6lowpan_chan_ops = {
867 .name = "L2CAP 6LoWPAN channel",
868 .new_connection = chan_new_conn_cb,
869 .recv = chan_recv_cb,
870 .close = chan_close_cb,
871 .state_change = chan_state_change_cb,
872 .ready = chan_ready_cb,
873 .resume = chan_resume_cb,
874 .suspend = chan_suspend_cb,
875 .get_sndtimeo = chan_get_sndtimeo_cb,
876 .alloc_skb = chan_alloc_skb_cb,
877
878 .teardown = l2cap_chan_no_teardown,
879 .defer = l2cap_chan_no_defer,
880 .set_shutdown = l2cap_chan_no_set_shutdown,
881};
882
883static int bt_6lowpan_connect(bdaddr_t *addr, u8 dst_type)
884{
885 struct l2cap_chan *chan;
886 int err;
887
888 chan = chan_create();
889 if (!chan)
890 return -EINVAL;
891
892 chan->ops = &bt_6lowpan_chan_ops;
893
894 err = l2cap_chan_connect(chan, cpu_to_le16(L2CAP_PSM_IPSP), 0,
895 addr, dst_type, L2CAP_CONN_TIMEOUT);
896
897 BT_DBG("chan %p err %d", chan, err);
898 if (err < 0)
899 l2cap_chan_put(chan);
900
901 return err;
902}
903
904static int bt_6lowpan_disconnect(struct l2cap_conn *conn, u8 dst_type)
905{
906 struct lowpan_peer *peer;
907
908 BT_DBG("conn %p dst type %u", conn, dst_type);
909
910 peer = lookup_peer(conn);
911 if (!peer)
912 return -ENOENT;
913
914 BT_DBG("peer %p chan %p", peer, peer->chan);
915
916 l2cap_chan_close(peer->chan, ENOENT);
917
918 return 0;
919}
920
921static struct l2cap_chan *bt_6lowpan_listen(void)
922{
923 bdaddr_t *addr = BDADDR_ANY;
924 struct l2cap_chan *chan;
925 int err;
926
927 if (!enable_6lowpan)
928 return NULL;
929
930 chan = chan_create();
931 if (!chan)
932 return NULL;
933
934 chan->ops = &bt_6lowpan_chan_ops;
935 chan->state = BT_LISTEN;
936 chan->src_type = BDADDR_LE_PUBLIC;
937
938 atomic_set(&chan->nesting, L2CAP_NESTING_PARENT);
939
940 BT_DBG("chan %p src type %u", chan, chan->src_type);
941
942 err = l2cap_add_psm(chan, addr, cpu_to_le16(L2CAP_PSM_IPSP));
943 if (err) {
944 l2cap_chan_put(chan);
945 BT_ERR("psm cannot be added err %d", err);
946 return NULL;
947 }
948
949 return chan;
950}
951
952static int get_l2cap_conn(char *buf, bdaddr_t *addr, u8 *addr_type,
953 struct l2cap_conn **conn)
954{
955 struct hci_conn *hcon;
956 struct hci_dev *hdev;
957 int n;
958
959 n = sscanf(buf, "%hhx:%hhx:%hhx:%hhx:%hhx:%hhx %hhu",
960 &addr->b[5], &addr->b[4], &addr->b[3],
961 &addr->b[2], &addr->b[1], &addr->b[0],
962 addr_type);
963
964 if (n < 7)
965 return -EINVAL;
966
967 /* The LE_PUBLIC address type is ignored because of BDADDR_ANY */
968 hdev = hci_get_route(addr, BDADDR_ANY, BDADDR_LE_PUBLIC);
969 if (!hdev)
970 return -ENOENT;
971
972 hci_dev_lock(hdev);
973 hcon = hci_conn_hash_lookup_le(hdev, addr, *addr_type);
974 hci_dev_unlock(hdev);
975 hci_dev_put(hdev);
976
977 if (!hcon)
978 return -ENOENT;
979
980 *conn = (struct l2cap_conn *)hcon->l2cap_data;
981
982 BT_DBG("conn %p dst %pMR type %u", *conn, &hcon->dst, hcon->dst_type);
983
984 return 0;
985}
986
987static void disconnect_all_peers(void)
988{
989 struct lowpan_btle_dev *entry;
990 struct lowpan_peer *peer, *tmp_peer, *new_peer;
991 struct list_head peers;
992
993 INIT_LIST_HEAD(&peers);
994
995 /* We make a separate list of peers as the close_cb() will
996 * modify the device peers list so it is better not to mess
997 * with the same list at the same time.
998 */
999
1000 rcu_read_lock();
1001
1002 list_for_each_entry_rcu(entry, &bt_6lowpan_devices, list) {
1003 list_for_each_entry_rcu(peer, &entry->peers, list) {
1004 new_peer = kmalloc(sizeof(*new_peer), GFP_ATOMIC);
1005 if (!new_peer)
1006 break;
1007
1008 new_peer->chan = peer->chan;
1009 INIT_LIST_HEAD(&new_peer->list);
1010
1011 list_add(&new_peer->list, &peers);
1012 }
1013 }
1014
1015 rcu_read_unlock();
1016
1017 spin_lock(&devices_lock);
1018 list_for_each_entry_safe(peer, tmp_peer, &peers, list) {
1019 l2cap_chan_close(peer->chan, ENOENT);
1020
1021 list_del_rcu(&peer->list);
1022 kfree_rcu(peer, rcu);
1023 }
1024 spin_unlock(&devices_lock);
1025}
1026
1027struct set_enable {
1028 struct work_struct work;
1029 bool flag;
1030};
1031
1032static void do_enable_set(struct work_struct *work)
1033{
1034 struct set_enable *set_enable = container_of(work,
1035 struct set_enable, work);
1036
1037 if (!set_enable->flag || enable_6lowpan != set_enable->flag)
1038 /* Disconnect existing connections if 6lowpan is
1039 * disabled
1040 */
1041 disconnect_all_peers();
1042
1043 enable_6lowpan = set_enable->flag;
1044
1045 mutex_lock(&set_lock);
1046 if (listen_chan) {
1047 l2cap_chan_close(listen_chan, 0);
1048 l2cap_chan_put(listen_chan);
1049 }
1050
1051 listen_chan = bt_6lowpan_listen();
1052 mutex_unlock(&set_lock);
1053
1054 kfree(set_enable);
1055}
1056
1057static int lowpan_enable_set(void *data, u64 val)
1058{
1059 struct set_enable *set_enable;
1060
1061 set_enable = kzalloc(sizeof(*set_enable), GFP_KERNEL);
1062 if (!set_enable)
1063 return -ENOMEM;
1064
1065 set_enable->flag = !!val;
1066 INIT_WORK(&set_enable->work, do_enable_set);
1067
1068 schedule_work(&set_enable->work);
1069
1070 return 0;
1071}
1072
1073static int lowpan_enable_get(void *data, u64 *val)
1074{
1075 *val = enable_6lowpan;
1076 return 0;
1077}
1078
1079DEFINE_DEBUGFS_ATTRIBUTE(lowpan_enable_fops, lowpan_enable_get,
1080 lowpan_enable_set, "%llu\n");
1081
1082static ssize_t lowpan_control_write(struct file *fp,
1083 const char __user *user_buffer,
1084 size_t count,
1085 loff_t *position)
1086{
1087 char buf[32];
1088 size_t buf_size = min(count, sizeof(buf) - 1);
1089 int ret;
1090 bdaddr_t addr;
1091 u8 addr_type;
1092 struct l2cap_conn *conn = NULL;
1093
1094 if (copy_from_user(buf, user_buffer, buf_size))
1095 return -EFAULT;
1096
1097 buf[buf_size] = '\0';
1098
1099 if (memcmp(buf, "connect ", 8) == 0) {
1100 ret = get_l2cap_conn(&buf[8], &addr, &addr_type, &conn);
1101 if (ret == -EINVAL)
1102 return ret;
1103
1104 mutex_lock(&set_lock);
1105 if (listen_chan) {
1106 l2cap_chan_close(listen_chan, 0);
1107 l2cap_chan_put(listen_chan);
1108 listen_chan = NULL;
1109 }
1110 mutex_unlock(&set_lock);
1111
1112 if (conn) {
1113 struct lowpan_peer *peer;
1114
1115 if (!is_bt_6lowpan(conn->hcon))
1116 return -EINVAL;
1117
1118 peer = lookup_peer(conn);
1119 if (peer) {
1120 BT_DBG("6LoWPAN connection already exists");
1121 return -EALREADY;
1122 }
1123
1124 BT_DBG("conn %p dst %pMR type %d user %u", conn,
1125 &conn->hcon->dst, conn->hcon->dst_type,
1126 addr_type);
1127 }
1128
1129 ret = bt_6lowpan_connect(&addr, addr_type);
1130 if (ret < 0)
1131 return ret;
1132
1133 return count;
1134 }
1135
1136 if (memcmp(buf, "disconnect ", 11) == 0) {
1137 ret = get_l2cap_conn(&buf[11], &addr, &addr_type, &conn);
1138 if (ret < 0)
1139 return ret;
1140
1141 ret = bt_6lowpan_disconnect(conn, addr_type);
1142 if (ret < 0)
1143 return ret;
1144
1145 return count;
1146 }
1147
1148 return count;
1149}
1150
1151static int lowpan_control_show(struct seq_file *f, void *ptr)
1152{
1153 struct lowpan_btle_dev *entry;
1154 struct lowpan_peer *peer;
1155
1156 spin_lock(&devices_lock);
1157
1158 list_for_each_entry(entry, &bt_6lowpan_devices, list) {
1159 list_for_each_entry(peer, &entry->peers, list)
1160 seq_printf(f, "%pMR (type %u)\n",
1161 &peer->chan->dst, peer->chan->dst_type);
1162 }
1163
1164 spin_unlock(&devices_lock);
1165
1166 return 0;
1167}
1168
1169static int lowpan_control_open(struct inode *inode, struct file *file)
1170{
1171 return single_open(file, lowpan_control_show, inode->i_private);
1172}
1173
1174static const struct file_operations lowpan_control_fops = {
1175 .open = lowpan_control_open,
1176 .read = seq_read,
1177 .write = lowpan_control_write,
1178 .llseek = seq_lseek,
1179 .release = single_release,
1180};
1181
1182static void disconnect_devices(void)
1183{
1184 struct lowpan_btle_dev *entry, *tmp, *new_dev;
1185 struct list_head devices;
1186
1187 INIT_LIST_HEAD(&devices);
1188
1189 /* We make a separate list of devices because the unregister_netdev()
1190 * will call device_event() which will also want to modify the same
1191 * devices list.
1192 */
1193
1194 rcu_read_lock();
1195
1196 list_for_each_entry_rcu(entry, &bt_6lowpan_devices, list) {
1197 new_dev = kmalloc(sizeof(*new_dev), GFP_ATOMIC);
1198 if (!new_dev)
1199 break;
1200
1201 new_dev->netdev = entry->netdev;
1202 INIT_LIST_HEAD(&new_dev->list);
1203
1204 list_add_rcu(&new_dev->list, &devices);
1205 }
1206
1207 rcu_read_unlock();
1208
1209 list_for_each_entry_safe(entry, tmp, &devices, list) {
1210 ifdown(entry->netdev);
1211 BT_DBG("Unregistering netdev %s %p",
1212 entry->netdev->name, entry->netdev);
1213 lowpan_unregister_netdev(entry->netdev);
1214 kfree(entry);
1215 }
1216}
1217
1218static int device_event(struct notifier_block *unused,
1219 unsigned long event, void *ptr)
1220{
1221 struct net_device *netdev = netdev_notifier_info_to_dev(ptr);
1222 struct lowpan_btle_dev *entry;
1223
1224 if (netdev->type != ARPHRD_6LOWPAN)
1225 return NOTIFY_DONE;
1226
1227 switch (event) {
1228 case NETDEV_UNREGISTER:
1229 spin_lock(&devices_lock);
1230 list_for_each_entry(entry, &bt_6lowpan_devices, list) {
1231 if (entry->netdev == netdev) {
1232 BT_DBG("Unregistered netdev %s %p",
1233 netdev->name, netdev);
1234 list_del(&entry->list);
1235 break;
1236 }
1237 }
1238 spin_unlock(&devices_lock);
1239 break;
1240 }
1241
1242 return NOTIFY_DONE;
1243}
1244
1245static struct notifier_block bt_6lowpan_dev_notifier = {
1246 .notifier_call = device_event,
1247};
1248
1249static int __init bt_6lowpan_init(void)
1250{
1251 lowpan_enable_debugfs = debugfs_create_file_unsafe("6lowpan_enable",
1252 0644, bt_debugfs,
1253 NULL,
1254 &lowpan_enable_fops);
1255 lowpan_control_debugfs = debugfs_create_file("6lowpan_control", 0644,
1256 bt_debugfs, NULL,
1257 &lowpan_control_fops);
1258
1259 return register_netdevice_notifier(&bt_6lowpan_dev_notifier);
1260}
1261
1262static void __exit bt_6lowpan_exit(void)
1263{
1264 debugfs_remove(lowpan_enable_debugfs);
1265 debugfs_remove(lowpan_control_debugfs);
1266
1267 if (listen_chan) {
1268 l2cap_chan_close(listen_chan, 0);
1269 l2cap_chan_put(listen_chan);
1270 }
1271
1272 disconnect_devices();
1273
1274 unregister_netdevice_notifier(&bt_6lowpan_dev_notifier);
1275}
1276
1277module_init(bt_6lowpan_init);
1278module_exit(bt_6lowpan_exit);
1279
1280MODULE_AUTHOR("Jukka Rissanen <jukka.rissanen@linux.intel.com>");
1281MODULE_DESCRIPTION("Bluetooth 6LoWPAN");
1282MODULE_VERSION(VERSION);
1283MODULE_LICENSE("GPL");
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 Copyright (c) 2013-2014 Intel Corp.
4
5*/
6
7#include <linux/if_arp.h>
8#include <linux/netdevice.h>
9#include <linux/etherdevice.h>
10#include <linux/module.h>
11#include <linux/debugfs.h>
12
13#include <net/ipv6.h>
14#include <net/ip6_route.h>
15#include <net/addrconf.h>
16#include <net/pkt_sched.h>
17
18#include <net/bluetooth/bluetooth.h>
19#include <net/bluetooth/hci_core.h>
20#include <net/bluetooth/l2cap.h>
21
22#include <net/6lowpan.h> /* for the compression support */
23
24#define VERSION "0.1"
25
26static struct dentry *lowpan_enable_debugfs;
27static struct dentry *lowpan_control_debugfs;
28
29#define IFACE_NAME_TEMPLATE "bt%d"
30
31struct skb_cb {
32 struct in6_addr addr;
33 struct in6_addr gw;
34 struct l2cap_chan *chan;
35};
36#define lowpan_cb(skb) ((struct skb_cb *)((skb)->cb))
37
38/* The devices list contains those devices that we are acting
39 * as a proxy. The BT 6LoWPAN device is a virtual device that
40 * connects to the Bluetooth LE device. The real connection to
41 * BT device is done via l2cap layer. There exists one
42 * virtual device / one BT 6LoWPAN network (=hciX device).
43 * The list contains struct lowpan_dev elements.
44 */
45static LIST_HEAD(bt_6lowpan_devices);
46static DEFINE_SPINLOCK(devices_lock);
47
48static bool enable_6lowpan;
49
50/* We are listening incoming connections via this channel
51 */
52static struct l2cap_chan *listen_chan;
53static DEFINE_MUTEX(set_lock);
54
55struct lowpan_peer {
56 struct list_head list;
57 struct rcu_head rcu;
58 struct l2cap_chan *chan;
59
60 /* peer addresses in various formats */
61 unsigned char lladdr[ETH_ALEN];
62 struct in6_addr peer_addr;
63};
64
65struct lowpan_btle_dev {
66 struct list_head list;
67
68 struct hci_dev *hdev;
69 struct net_device *netdev;
70 struct list_head peers;
71 atomic_t peer_count; /* number of items in peers list */
72
73 struct work_struct delete_netdev;
74 struct delayed_work notify_peers;
75};
76
77static inline struct lowpan_btle_dev *
78lowpan_btle_dev(const struct net_device *netdev)
79{
80 return (struct lowpan_btle_dev *)lowpan_dev(netdev)->priv;
81}
82
83static inline void peer_add(struct lowpan_btle_dev *dev,
84 struct lowpan_peer *peer)
85{
86 list_add_rcu(&peer->list, &dev->peers);
87 atomic_inc(&dev->peer_count);
88}
89
90static inline bool peer_del(struct lowpan_btle_dev *dev,
91 struct lowpan_peer *peer)
92{
93 list_del_rcu(&peer->list);
94 kfree_rcu(peer, rcu);
95
96 module_put(THIS_MODULE);
97
98 if (atomic_dec_and_test(&dev->peer_count)) {
99 BT_DBG("last peer");
100 return true;
101 }
102
103 return false;
104}
105
106static inline struct lowpan_peer *peer_lookup_ba(struct lowpan_btle_dev *dev,
107 bdaddr_t *ba, __u8 type)
108{
109 struct lowpan_peer *peer;
110
111 BT_DBG("peers %d addr %pMR type %d", atomic_read(&dev->peer_count),
112 ba, type);
113
114 rcu_read_lock();
115
116 list_for_each_entry_rcu(peer, &dev->peers, list) {
117 BT_DBG("dst addr %pMR dst type %d",
118 &peer->chan->dst, peer->chan->dst_type);
119
120 if (bacmp(&peer->chan->dst, ba))
121 continue;
122
123 if (type == peer->chan->dst_type) {
124 rcu_read_unlock();
125 return peer;
126 }
127 }
128
129 rcu_read_unlock();
130
131 return NULL;
132}
133
134static inline struct lowpan_peer *
135__peer_lookup_chan(struct lowpan_btle_dev *dev, struct l2cap_chan *chan)
136{
137 struct lowpan_peer *peer;
138
139 list_for_each_entry_rcu(peer, &dev->peers, list) {
140 if (peer->chan == chan)
141 return peer;
142 }
143
144 return NULL;
145}
146
147static inline struct lowpan_peer *
148__peer_lookup_conn(struct lowpan_btle_dev *dev, struct l2cap_conn *conn)
149{
150 struct lowpan_peer *peer;
151
152 list_for_each_entry_rcu(peer, &dev->peers, list) {
153 if (peer->chan->conn == conn)
154 return peer;
155 }
156
157 return NULL;
158}
159
160static inline struct lowpan_peer *peer_lookup_dst(struct lowpan_btle_dev *dev,
161 struct in6_addr *daddr,
162 struct sk_buff *skb)
163{
164 struct rt6_info *rt = (struct rt6_info *)skb_dst(skb);
165 int count = atomic_read(&dev->peer_count);
166 const struct in6_addr *nexthop;
167 struct lowpan_peer *peer;
168 struct neighbour *neigh;
169
170 BT_DBG("peers %d addr %pI6c rt %p", count, daddr, rt);
171
172 if (!rt) {
173 if (ipv6_addr_any(&lowpan_cb(skb)->gw)) {
174 /* There is neither route nor gateway,
175 * probably the destination is a direct peer.
176 */
177 nexthop = daddr;
178 } else {
179 /* There is a known gateway
180 */
181 nexthop = &lowpan_cb(skb)->gw;
182 }
183 } else {
184 nexthop = rt6_nexthop(rt, daddr);
185
186 /* We need to remember the address because it is needed
187 * by bt_xmit() when sending the packet. In bt_xmit(), the
188 * destination routing info is not set.
189 */
190 memcpy(&lowpan_cb(skb)->gw, nexthop, sizeof(struct in6_addr));
191 }
192
193 BT_DBG("gw %pI6c", nexthop);
194
195 rcu_read_lock();
196
197 list_for_each_entry_rcu(peer, &dev->peers, list) {
198 BT_DBG("dst addr %pMR dst type %d ip %pI6c",
199 &peer->chan->dst, peer->chan->dst_type,
200 &peer->peer_addr);
201
202 if (!ipv6_addr_cmp(&peer->peer_addr, nexthop)) {
203 rcu_read_unlock();
204 return peer;
205 }
206 }
207
208 /* use the neighbour cache for matching addresses assigned by SLAAC
209 */
210 neigh = __ipv6_neigh_lookup(dev->netdev, nexthop);
211 if (neigh) {
212 list_for_each_entry_rcu(peer, &dev->peers, list) {
213 if (!memcmp(neigh->ha, peer->lladdr, ETH_ALEN)) {
214 neigh_release(neigh);
215 rcu_read_unlock();
216 return peer;
217 }
218 }
219 neigh_release(neigh);
220 }
221
222 rcu_read_unlock();
223
224 return NULL;
225}
226
227static struct lowpan_peer *lookup_peer(struct l2cap_conn *conn)
228{
229 struct lowpan_btle_dev *entry;
230 struct lowpan_peer *peer = NULL;
231
232 rcu_read_lock();
233
234 list_for_each_entry_rcu(entry, &bt_6lowpan_devices, list) {
235 peer = __peer_lookup_conn(entry, conn);
236 if (peer)
237 break;
238 }
239
240 rcu_read_unlock();
241
242 return peer;
243}
244
245static struct lowpan_btle_dev *lookup_dev(struct l2cap_conn *conn)
246{
247 struct lowpan_btle_dev *entry;
248 struct lowpan_btle_dev *dev = NULL;
249
250 rcu_read_lock();
251
252 list_for_each_entry_rcu(entry, &bt_6lowpan_devices, list) {
253 if (conn->hcon->hdev == entry->hdev) {
254 dev = entry;
255 break;
256 }
257 }
258
259 rcu_read_unlock();
260
261 return dev;
262}
263
264static int give_skb_to_upper(struct sk_buff *skb, struct net_device *dev)
265{
266 struct sk_buff *skb_cp;
267
268 skb_cp = skb_copy(skb, GFP_ATOMIC);
269 if (!skb_cp)
270 return NET_RX_DROP;
271
272 return netif_rx_ni(skb_cp);
273}
274
275static int iphc_decompress(struct sk_buff *skb, struct net_device *netdev,
276 struct lowpan_peer *peer)
277{
278 const u8 *saddr;
279
280 saddr = peer->lladdr;
281
282 return lowpan_header_decompress(skb, netdev, netdev->dev_addr, saddr);
283}
284
285static int recv_pkt(struct sk_buff *skb, struct net_device *dev,
286 struct lowpan_peer *peer)
287{
288 struct sk_buff *local_skb;
289 int ret;
290
291 if (!netif_running(dev))
292 goto drop;
293
294 if (dev->type != ARPHRD_6LOWPAN || !skb->len)
295 goto drop;
296
297 skb_reset_network_header(skb);
298
299 skb = skb_share_check(skb, GFP_ATOMIC);
300 if (!skb)
301 goto drop;
302
303 /* check that it's our buffer */
304 if (lowpan_is_ipv6(*skb_network_header(skb))) {
305 /* Pull off the 1-byte of 6lowpan header. */
306 skb_pull(skb, 1);
307
308 /* Copy the packet so that the IPv6 header is
309 * properly aligned.
310 */
311 local_skb = skb_copy_expand(skb, NET_SKB_PAD - 1,
312 skb_tailroom(skb), GFP_ATOMIC);
313 if (!local_skb)
314 goto drop;
315
316 local_skb->protocol = htons(ETH_P_IPV6);
317 local_skb->pkt_type = PACKET_HOST;
318 local_skb->dev = dev;
319
320 skb_set_transport_header(local_skb, sizeof(struct ipv6hdr));
321
322 if (give_skb_to_upper(local_skb, dev) != NET_RX_SUCCESS) {
323 kfree_skb(local_skb);
324 goto drop;
325 }
326
327 dev->stats.rx_bytes += skb->len;
328 dev->stats.rx_packets++;
329
330 consume_skb(local_skb);
331 consume_skb(skb);
332 } else if (lowpan_is_iphc(*skb_network_header(skb))) {
333 local_skb = skb_clone(skb, GFP_ATOMIC);
334 if (!local_skb)
335 goto drop;
336
337 local_skb->dev = dev;
338
339 ret = iphc_decompress(local_skb, dev, peer);
340 if (ret < 0) {
341 BT_DBG("iphc_decompress failed: %d", ret);
342 kfree_skb(local_skb);
343 goto drop;
344 }
345
346 local_skb->protocol = htons(ETH_P_IPV6);
347 local_skb->pkt_type = PACKET_HOST;
348
349 if (give_skb_to_upper(local_skb, dev)
350 != NET_RX_SUCCESS) {
351 kfree_skb(local_skb);
352 goto drop;
353 }
354
355 dev->stats.rx_bytes += skb->len;
356 dev->stats.rx_packets++;
357
358 consume_skb(local_skb);
359 consume_skb(skb);
360 } else {
361 BT_DBG("unknown packet type");
362 goto drop;
363 }
364
365 return NET_RX_SUCCESS;
366
367drop:
368 dev->stats.rx_dropped++;
369 return NET_RX_DROP;
370}
371
372/* Packet from BT LE device */
373static int chan_recv_cb(struct l2cap_chan *chan, struct sk_buff *skb)
374{
375 struct lowpan_btle_dev *dev;
376 struct lowpan_peer *peer;
377 int err;
378
379 peer = lookup_peer(chan->conn);
380 if (!peer)
381 return -ENOENT;
382
383 dev = lookup_dev(chan->conn);
384 if (!dev || !dev->netdev)
385 return -ENOENT;
386
387 err = recv_pkt(skb, dev->netdev, peer);
388 if (err) {
389 BT_DBG("recv pkt %d", err);
390 err = -EAGAIN;
391 }
392
393 return err;
394}
395
396static int setup_header(struct sk_buff *skb, struct net_device *netdev,
397 bdaddr_t *peer_addr, u8 *peer_addr_type)
398{
399 struct in6_addr ipv6_daddr;
400 struct ipv6hdr *hdr;
401 struct lowpan_btle_dev *dev;
402 struct lowpan_peer *peer;
403 u8 *daddr;
404 int err, status = 0;
405
406 hdr = ipv6_hdr(skb);
407
408 dev = lowpan_btle_dev(netdev);
409
410 memcpy(&ipv6_daddr, &hdr->daddr, sizeof(ipv6_daddr));
411
412 if (ipv6_addr_is_multicast(&ipv6_daddr)) {
413 lowpan_cb(skb)->chan = NULL;
414 daddr = NULL;
415 } else {
416 BT_DBG("dest IP %pI6c", &ipv6_daddr);
417
418 /* The packet might be sent to 6lowpan interface
419 * because of routing (either via default route
420 * or user set route) so get peer according to
421 * the destination address.
422 */
423 peer = peer_lookup_dst(dev, &ipv6_daddr, skb);
424 if (!peer) {
425 BT_DBG("no such peer");
426 return -ENOENT;
427 }
428
429 daddr = peer->lladdr;
430 *peer_addr = peer->chan->dst;
431 *peer_addr_type = peer->chan->dst_type;
432 lowpan_cb(skb)->chan = peer->chan;
433
434 status = 1;
435 }
436
437 lowpan_header_compress(skb, netdev, daddr, dev->netdev->dev_addr);
438
439 err = dev_hard_header(skb, netdev, ETH_P_IPV6, NULL, NULL, 0);
440 if (err < 0)
441 return err;
442
443 return status;
444}
445
446static int header_create(struct sk_buff *skb, struct net_device *netdev,
447 unsigned short type, const void *_daddr,
448 const void *_saddr, unsigned int len)
449{
450 if (type != ETH_P_IPV6)
451 return -EINVAL;
452
453 return 0;
454}
455
456/* Packet to BT LE device */
457static int send_pkt(struct l2cap_chan *chan, struct sk_buff *skb,
458 struct net_device *netdev)
459{
460 struct msghdr msg;
461 struct kvec iv;
462 int err;
463
464 /* Remember the skb so that we can send EAGAIN to the caller if
465 * we run out of credits.
466 */
467 chan->data = skb;
468
469 iv.iov_base = skb->data;
470 iv.iov_len = skb->len;
471
472 memset(&msg, 0, sizeof(msg));
473 iov_iter_kvec(&msg.msg_iter, WRITE, &iv, 1, skb->len);
474
475 err = l2cap_chan_send(chan, &msg, skb->len);
476 if (err > 0) {
477 netdev->stats.tx_bytes += err;
478 netdev->stats.tx_packets++;
479 return 0;
480 }
481
482 if (err < 0)
483 netdev->stats.tx_errors++;
484
485 return err;
486}
487
488static int send_mcast_pkt(struct sk_buff *skb, struct net_device *netdev)
489{
490 struct sk_buff *local_skb;
491 struct lowpan_btle_dev *entry;
492 int err = 0;
493
494 rcu_read_lock();
495
496 list_for_each_entry_rcu(entry, &bt_6lowpan_devices, list) {
497 struct lowpan_peer *pentry;
498 struct lowpan_btle_dev *dev;
499
500 if (entry->netdev != netdev)
501 continue;
502
503 dev = lowpan_btle_dev(entry->netdev);
504
505 list_for_each_entry_rcu(pentry, &dev->peers, list) {
506 int ret;
507
508 local_skb = skb_clone(skb, GFP_ATOMIC);
509
510 BT_DBG("xmit %s to %pMR type %d IP %pI6c chan %p",
511 netdev->name,
512 &pentry->chan->dst, pentry->chan->dst_type,
513 &pentry->peer_addr, pentry->chan);
514 ret = send_pkt(pentry->chan, local_skb, netdev);
515 if (ret < 0)
516 err = ret;
517
518 kfree_skb(local_skb);
519 }
520 }
521
522 rcu_read_unlock();
523
524 return err;
525}
526
527static netdev_tx_t bt_xmit(struct sk_buff *skb, struct net_device *netdev)
528{
529 int err = 0;
530 bdaddr_t addr;
531 u8 addr_type;
532
533 /* We must take a copy of the skb before we modify/replace the ipv6
534 * header as the header could be used elsewhere
535 */
536 skb = skb_unshare(skb, GFP_ATOMIC);
537 if (!skb)
538 return NET_XMIT_DROP;
539
540 /* Return values from setup_header()
541 * <0 - error, packet is dropped
542 * 0 - this is a multicast packet
543 * 1 - this is unicast packet
544 */
545 err = setup_header(skb, netdev, &addr, &addr_type);
546 if (err < 0) {
547 kfree_skb(skb);
548 return NET_XMIT_DROP;
549 }
550
551 if (err) {
552 if (lowpan_cb(skb)->chan) {
553 BT_DBG("xmit %s to %pMR type %d IP %pI6c chan %p",
554 netdev->name, &addr, addr_type,
555 &lowpan_cb(skb)->addr, lowpan_cb(skb)->chan);
556 err = send_pkt(lowpan_cb(skb)->chan, skb, netdev);
557 } else {
558 err = -ENOENT;
559 }
560 } else {
561 /* We need to send the packet to every device behind this
562 * interface.
563 */
564 err = send_mcast_pkt(skb, netdev);
565 }
566
567 dev_kfree_skb(skb);
568
569 if (err)
570 BT_DBG("ERROR: xmit failed (%d)", err);
571
572 return err < 0 ? NET_XMIT_DROP : err;
573}
574
575static int bt_dev_init(struct net_device *dev)
576{
577 netdev_lockdep_set_classes(dev);
578
579 return 0;
580}
581
582static const struct net_device_ops netdev_ops = {
583 .ndo_init = bt_dev_init,
584 .ndo_start_xmit = bt_xmit,
585};
586
587static const struct header_ops header_ops = {
588 .create = header_create,
589};
590
591static void netdev_setup(struct net_device *dev)
592{
593 dev->hard_header_len = 0;
594 dev->needed_tailroom = 0;
595 dev->flags = IFF_RUNNING | IFF_MULTICAST;
596 dev->watchdog_timeo = 0;
597 dev->tx_queue_len = DEFAULT_TX_QUEUE_LEN;
598
599 dev->netdev_ops = &netdev_ops;
600 dev->header_ops = &header_ops;
601 dev->needs_free_netdev = true;
602}
603
604static struct device_type bt_type = {
605 .name = "bluetooth",
606};
607
608static void ifup(struct net_device *netdev)
609{
610 int err;
611
612 rtnl_lock();
613 err = dev_open(netdev, NULL);
614 if (err < 0)
615 BT_INFO("iface %s cannot be opened (%d)", netdev->name, err);
616 rtnl_unlock();
617}
618
619static void ifdown(struct net_device *netdev)
620{
621 rtnl_lock();
622 dev_close(netdev);
623 rtnl_unlock();
624}
625
626static void do_notify_peers(struct work_struct *work)
627{
628 struct lowpan_btle_dev *dev = container_of(work, struct lowpan_btle_dev,
629 notify_peers.work);
630
631 netdev_notify_peers(dev->netdev); /* send neighbour adv at startup */
632}
633
634static bool is_bt_6lowpan(struct hci_conn *hcon)
635{
636 if (hcon->type != LE_LINK)
637 return false;
638
639 if (!enable_6lowpan)
640 return false;
641
642 return true;
643}
644
645static struct l2cap_chan *chan_create(void)
646{
647 struct l2cap_chan *chan;
648
649 chan = l2cap_chan_create();
650 if (!chan)
651 return NULL;
652
653 l2cap_chan_set_defaults(chan);
654
655 chan->chan_type = L2CAP_CHAN_CONN_ORIENTED;
656 chan->mode = L2CAP_MODE_LE_FLOWCTL;
657 chan->imtu = 1280;
658
659 return chan;
660}
661
662static struct l2cap_chan *add_peer_chan(struct l2cap_chan *chan,
663 struct lowpan_btle_dev *dev,
664 bool new_netdev)
665{
666 struct lowpan_peer *peer;
667
668 peer = kzalloc(sizeof(*peer), GFP_ATOMIC);
669 if (!peer)
670 return NULL;
671
672 peer->chan = chan;
673 memset(&peer->peer_addr, 0, sizeof(struct in6_addr));
674
675 baswap((void *)peer->lladdr, &chan->dst);
676
677 lowpan_iphc_uncompress_eui48_lladdr(&peer->peer_addr, peer->lladdr);
678
679 spin_lock(&devices_lock);
680 INIT_LIST_HEAD(&peer->list);
681 peer_add(dev, peer);
682 spin_unlock(&devices_lock);
683
684 /* Notifying peers about us needs to be done without locks held */
685 if (new_netdev)
686 INIT_DELAYED_WORK(&dev->notify_peers, do_notify_peers);
687 schedule_delayed_work(&dev->notify_peers, msecs_to_jiffies(100));
688
689 return peer->chan;
690}
691
692static int setup_netdev(struct l2cap_chan *chan, struct lowpan_btle_dev **dev)
693{
694 struct net_device *netdev;
695 int err = 0;
696
697 netdev = alloc_netdev(LOWPAN_PRIV_SIZE(sizeof(struct lowpan_btle_dev)),
698 IFACE_NAME_TEMPLATE, NET_NAME_UNKNOWN,
699 netdev_setup);
700 if (!netdev)
701 return -ENOMEM;
702
703 netdev->addr_assign_type = NET_ADDR_PERM;
704 baswap((void *)netdev->dev_addr, &chan->src);
705
706 netdev->netdev_ops = &netdev_ops;
707 SET_NETDEV_DEV(netdev, &chan->conn->hcon->hdev->dev);
708 SET_NETDEV_DEVTYPE(netdev, &bt_type);
709
710 *dev = lowpan_btle_dev(netdev);
711 (*dev)->netdev = netdev;
712 (*dev)->hdev = chan->conn->hcon->hdev;
713 INIT_LIST_HEAD(&(*dev)->peers);
714
715 spin_lock(&devices_lock);
716 INIT_LIST_HEAD(&(*dev)->list);
717 list_add_rcu(&(*dev)->list, &bt_6lowpan_devices);
718 spin_unlock(&devices_lock);
719
720 err = lowpan_register_netdev(netdev, LOWPAN_LLTYPE_BTLE);
721 if (err < 0) {
722 BT_INFO("register_netdev failed %d", err);
723 spin_lock(&devices_lock);
724 list_del_rcu(&(*dev)->list);
725 spin_unlock(&devices_lock);
726 free_netdev(netdev);
727 goto out;
728 }
729
730 BT_DBG("ifindex %d peer bdaddr %pMR type %d my addr %pMR type %d",
731 netdev->ifindex, &chan->dst, chan->dst_type,
732 &chan->src, chan->src_type);
733 set_bit(__LINK_STATE_PRESENT, &netdev->state);
734
735 return 0;
736
737out:
738 return err;
739}
740
741static inline void chan_ready_cb(struct l2cap_chan *chan)
742{
743 struct lowpan_btle_dev *dev;
744 bool new_netdev = false;
745
746 dev = lookup_dev(chan->conn);
747
748 BT_DBG("chan %p conn %p dev %p", chan, chan->conn, dev);
749
750 if (!dev) {
751 if (setup_netdev(chan, &dev) < 0) {
752 l2cap_chan_del(chan, -ENOENT);
753 return;
754 }
755 new_netdev = true;
756 }
757
758 if (!try_module_get(THIS_MODULE))
759 return;
760
761 add_peer_chan(chan, dev, new_netdev);
762 ifup(dev->netdev);
763}
764
765static inline struct l2cap_chan *chan_new_conn_cb(struct l2cap_chan *pchan)
766{
767 struct l2cap_chan *chan;
768
769 chan = chan_create();
770 if (!chan)
771 return NULL;
772
773 chan->ops = pchan->ops;
774
775 BT_DBG("chan %p pchan %p", chan, pchan);
776
777 return chan;
778}
779
780static void delete_netdev(struct work_struct *work)
781{
782 struct lowpan_btle_dev *entry = container_of(work,
783 struct lowpan_btle_dev,
784 delete_netdev);
785
786 lowpan_unregister_netdev(entry->netdev);
787
788 /* The entry pointer is deleted by the netdev destructor. */
789}
790
791static void chan_close_cb(struct l2cap_chan *chan)
792{
793 struct lowpan_btle_dev *entry;
794 struct lowpan_btle_dev *dev = NULL;
795 struct lowpan_peer *peer;
796 int err = -ENOENT;
797 bool last = false, remove = true;
798
799 BT_DBG("chan %p conn %p", chan, chan->conn);
800
801 if (chan->conn && chan->conn->hcon) {
802 if (!is_bt_6lowpan(chan->conn->hcon))
803 return;
804
805 /* If conn is set, then the netdev is also there and we should
806 * not remove it.
807 */
808 remove = false;
809 }
810
811 spin_lock(&devices_lock);
812
813 list_for_each_entry_rcu(entry, &bt_6lowpan_devices, list) {
814 dev = lowpan_btle_dev(entry->netdev);
815 peer = __peer_lookup_chan(dev, chan);
816 if (peer) {
817 last = peer_del(dev, peer);
818 err = 0;
819
820 BT_DBG("dev %p removing %speer %p", dev,
821 last ? "last " : "1 ", peer);
822 BT_DBG("chan %p orig refcnt %d", chan,
823 kref_read(&chan->kref));
824
825 l2cap_chan_put(chan);
826 break;
827 }
828 }
829
830 if (!err && last && dev && !atomic_read(&dev->peer_count)) {
831 spin_unlock(&devices_lock);
832
833 cancel_delayed_work_sync(&dev->notify_peers);
834
835 ifdown(dev->netdev);
836
837 if (remove) {
838 INIT_WORK(&entry->delete_netdev, delete_netdev);
839 schedule_work(&entry->delete_netdev);
840 }
841 } else {
842 spin_unlock(&devices_lock);
843 }
844
845 return;
846}
847
848static void chan_state_change_cb(struct l2cap_chan *chan, int state, int err)
849{
850 BT_DBG("chan %p conn %p state %s err %d", chan, chan->conn,
851 state_to_string(state), err);
852}
853
854static struct sk_buff *chan_alloc_skb_cb(struct l2cap_chan *chan,
855 unsigned long hdr_len,
856 unsigned long len, int nb)
857{
858 /* Note that we must allocate using GFP_ATOMIC here as
859 * this function is called originally from netdev hard xmit
860 * function in atomic context.
861 */
862 return bt_skb_alloc(hdr_len + len, GFP_ATOMIC);
863}
864
865static void chan_suspend_cb(struct l2cap_chan *chan)
866{
867 struct lowpan_btle_dev *dev;
868
869 BT_DBG("chan %p suspend", chan);
870
871 dev = lookup_dev(chan->conn);
872 if (!dev || !dev->netdev)
873 return;
874
875 netif_stop_queue(dev->netdev);
876}
877
878static void chan_resume_cb(struct l2cap_chan *chan)
879{
880 struct lowpan_btle_dev *dev;
881
882 BT_DBG("chan %p resume", chan);
883
884 dev = lookup_dev(chan->conn);
885 if (!dev || !dev->netdev)
886 return;
887
888 netif_wake_queue(dev->netdev);
889}
890
891static long chan_get_sndtimeo_cb(struct l2cap_chan *chan)
892{
893 return L2CAP_CONN_TIMEOUT;
894}
895
896static const struct l2cap_ops bt_6lowpan_chan_ops = {
897 .name = "L2CAP 6LoWPAN channel",
898 .new_connection = chan_new_conn_cb,
899 .recv = chan_recv_cb,
900 .close = chan_close_cb,
901 .state_change = chan_state_change_cb,
902 .ready = chan_ready_cb,
903 .resume = chan_resume_cb,
904 .suspend = chan_suspend_cb,
905 .get_sndtimeo = chan_get_sndtimeo_cb,
906 .alloc_skb = chan_alloc_skb_cb,
907
908 .teardown = l2cap_chan_no_teardown,
909 .defer = l2cap_chan_no_defer,
910 .set_shutdown = l2cap_chan_no_set_shutdown,
911};
912
913static inline __u8 bdaddr_type(__u8 type)
914{
915 if (type == ADDR_LE_DEV_PUBLIC)
916 return BDADDR_LE_PUBLIC;
917 else
918 return BDADDR_LE_RANDOM;
919}
920
921static int bt_6lowpan_connect(bdaddr_t *addr, u8 dst_type)
922{
923 struct l2cap_chan *chan;
924 int err;
925
926 chan = chan_create();
927 if (!chan)
928 return -EINVAL;
929
930 chan->ops = &bt_6lowpan_chan_ops;
931
932 err = l2cap_chan_connect(chan, cpu_to_le16(L2CAP_PSM_IPSP), 0,
933 addr, dst_type);
934
935 BT_DBG("chan %p err %d", chan, err);
936 if (err < 0)
937 l2cap_chan_put(chan);
938
939 return err;
940}
941
942static int bt_6lowpan_disconnect(struct l2cap_conn *conn, u8 dst_type)
943{
944 struct lowpan_peer *peer;
945
946 BT_DBG("conn %p dst type %d", conn, dst_type);
947
948 peer = lookup_peer(conn);
949 if (!peer)
950 return -ENOENT;
951
952 BT_DBG("peer %p chan %p", peer, peer->chan);
953
954 l2cap_chan_close(peer->chan, ENOENT);
955
956 return 0;
957}
958
959static struct l2cap_chan *bt_6lowpan_listen(void)
960{
961 bdaddr_t *addr = BDADDR_ANY;
962 struct l2cap_chan *chan;
963 int err;
964
965 if (!enable_6lowpan)
966 return NULL;
967
968 chan = chan_create();
969 if (!chan)
970 return NULL;
971
972 chan->ops = &bt_6lowpan_chan_ops;
973 chan->state = BT_LISTEN;
974 chan->src_type = BDADDR_LE_PUBLIC;
975
976 atomic_set(&chan->nesting, L2CAP_NESTING_PARENT);
977
978 BT_DBG("chan %p src type %d", chan, chan->src_type);
979
980 err = l2cap_add_psm(chan, addr, cpu_to_le16(L2CAP_PSM_IPSP));
981 if (err) {
982 l2cap_chan_put(chan);
983 BT_ERR("psm cannot be added err %d", err);
984 return NULL;
985 }
986
987 return chan;
988}
989
990static int get_l2cap_conn(char *buf, bdaddr_t *addr, u8 *addr_type,
991 struct l2cap_conn **conn)
992{
993 struct hci_conn *hcon;
994 struct hci_dev *hdev;
995 int n;
996
997 n = sscanf(buf, "%hhx:%hhx:%hhx:%hhx:%hhx:%hhx %hhu",
998 &addr->b[5], &addr->b[4], &addr->b[3],
999 &addr->b[2], &addr->b[1], &addr->b[0],
1000 addr_type);
1001
1002 if (n < 7)
1003 return -EINVAL;
1004
1005 /* The LE_PUBLIC address type is ignored because of BDADDR_ANY */
1006 hdev = hci_get_route(addr, BDADDR_ANY, BDADDR_LE_PUBLIC);
1007 if (!hdev)
1008 return -ENOENT;
1009
1010 hci_dev_lock(hdev);
1011 hcon = hci_conn_hash_lookup_le(hdev, addr, *addr_type);
1012 hci_dev_unlock(hdev);
1013
1014 if (!hcon)
1015 return -ENOENT;
1016
1017 *conn = (struct l2cap_conn *)hcon->l2cap_data;
1018
1019 BT_DBG("conn %p dst %pMR type %d", *conn, &hcon->dst, hcon->dst_type);
1020
1021 return 0;
1022}
1023
1024static void disconnect_all_peers(void)
1025{
1026 struct lowpan_btle_dev *entry;
1027 struct lowpan_peer *peer, *tmp_peer, *new_peer;
1028 struct list_head peers;
1029
1030 INIT_LIST_HEAD(&peers);
1031
1032 /* We make a separate list of peers as the close_cb() will
1033 * modify the device peers list so it is better not to mess
1034 * with the same list at the same time.
1035 */
1036
1037 rcu_read_lock();
1038
1039 list_for_each_entry_rcu(entry, &bt_6lowpan_devices, list) {
1040 list_for_each_entry_rcu(peer, &entry->peers, list) {
1041 new_peer = kmalloc(sizeof(*new_peer), GFP_ATOMIC);
1042 if (!new_peer)
1043 break;
1044
1045 new_peer->chan = peer->chan;
1046 INIT_LIST_HEAD(&new_peer->list);
1047
1048 list_add(&new_peer->list, &peers);
1049 }
1050 }
1051
1052 rcu_read_unlock();
1053
1054 spin_lock(&devices_lock);
1055 list_for_each_entry_safe(peer, tmp_peer, &peers, list) {
1056 l2cap_chan_close(peer->chan, ENOENT);
1057
1058 list_del_rcu(&peer->list);
1059 kfree_rcu(peer, rcu);
1060 }
1061 spin_unlock(&devices_lock);
1062}
1063
1064struct set_enable {
1065 struct work_struct work;
1066 bool flag;
1067};
1068
1069static void do_enable_set(struct work_struct *work)
1070{
1071 struct set_enable *set_enable = container_of(work,
1072 struct set_enable, work);
1073
1074 if (!set_enable->flag || enable_6lowpan != set_enable->flag)
1075 /* Disconnect existing connections if 6lowpan is
1076 * disabled
1077 */
1078 disconnect_all_peers();
1079
1080 enable_6lowpan = set_enable->flag;
1081
1082 mutex_lock(&set_lock);
1083 if (listen_chan) {
1084 l2cap_chan_close(listen_chan, 0);
1085 l2cap_chan_put(listen_chan);
1086 }
1087
1088 listen_chan = bt_6lowpan_listen();
1089 mutex_unlock(&set_lock);
1090
1091 kfree(set_enable);
1092}
1093
1094static int lowpan_enable_set(void *data, u64 val)
1095{
1096 struct set_enable *set_enable;
1097
1098 set_enable = kzalloc(sizeof(*set_enable), GFP_KERNEL);
1099 if (!set_enable)
1100 return -ENOMEM;
1101
1102 set_enable->flag = !!val;
1103 INIT_WORK(&set_enable->work, do_enable_set);
1104
1105 schedule_work(&set_enable->work);
1106
1107 return 0;
1108}
1109
1110static int lowpan_enable_get(void *data, u64 *val)
1111{
1112 *val = enable_6lowpan;
1113 return 0;
1114}
1115
1116DEFINE_DEBUGFS_ATTRIBUTE(lowpan_enable_fops, lowpan_enable_get,
1117 lowpan_enable_set, "%llu\n");
1118
1119static ssize_t lowpan_control_write(struct file *fp,
1120 const char __user *user_buffer,
1121 size_t count,
1122 loff_t *position)
1123{
1124 char buf[32];
1125 size_t buf_size = min(count, sizeof(buf) - 1);
1126 int ret;
1127 bdaddr_t addr;
1128 u8 addr_type;
1129 struct l2cap_conn *conn = NULL;
1130
1131 if (copy_from_user(buf, user_buffer, buf_size))
1132 return -EFAULT;
1133
1134 buf[buf_size] = '\0';
1135
1136 if (memcmp(buf, "connect ", 8) == 0) {
1137 ret = get_l2cap_conn(&buf[8], &addr, &addr_type, &conn);
1138 if (ret == -EINVAL)
1139 return ret;
1140
1141 mutex_lock(&set_lock);
1142 if (listen_chan) {
1143 l2cap_chan_close(listen_chan, 0);
1144 l2cap_chan_put(listen_chan);
1145 listen_chan = NULL;
1146 }
1147 mutex_unlock(&set_lock);
1148
1149 if (conn) {
1150 struct lowpan_peer *peer;
1151
1152 if (!is_bt_6lowpan(conn->hcon))
1153 return -EINVAL;
1154
1155 peer = lookup_peer(conn);
1156 if (peer) {
1157 BT_DBG("6LoWPAN connection already exists");
1158 return -EALREADY;
1159 }
1160
1161 BT_DBG("conn %p dst %pMR type %d user %d", conn,
1162 &conn->hcon->dst, conn->hcon->dst_type,
1163 addr_type);
1164 }
1165
1166 ret = bt_6lowpan_connect(&addr, addr_type);
1167 if (ret < 0)
1168 return ret;
1169
1170 return count;
1171 }
1172
1173 if (memcmp(buf, "disconnect ", 11) == 0) {
1174 ret = get_l2cap_conn(&buf[11], &addr, &addr_type, &conn);
1175 if (ret < 0)
1176 return ret;
1177
1178 ret = bt_6lowpan_disconnect(conn, addr_type);
1179 if (ret < 0)
1180 return ret;
1181
1182 return count;
1183 }
1184
1185 return count;
1186}
1187
1188static int lowpan_control_show(struct seq_file *f, void *ptr)
1189{
1190 struct lowpan_btle_dev *entry;
1191 struct lowpan_peer *peer;
1192
1193 spin_lock(&devices_lock);
1194
1195 list_for_each_entry(entry, &bt_6lowpan_devices, list) {
1196 list_for_each_entry(peer, &entry->peers, list)
1197 seq_printf(f, "%pMR (type %u)\n",
1198 &peer->chan->dst, peer->chan->dst_type);
1199 }
1200
1201 spin_unlock(&devices_lock);
1202
1203 return 0;
1204}
1205
1206static int lowpan_control_open(struct inode *inode, struct file *file)
1207{
1208 return single_open(file, lowpan_control_show, inode->i_private);
1209}
1210
1211static const struct file_operations lowpan_control_fops = {
1212 .open = lowpan_control_open,
1213 .read = seq_read,
1214 .write = lowpan_control_write,
1215 .llseek = seq_lseek,
1216 .release = single_release,
1217};
1218
1219static void disconnect_devices(void)
1220{
1221 struct lowpan_btle_dev *entry, *tmp, *new_dev;
1222 struct list_head devices;
1223
1224 INIT_LIST_HEAD(&devices);
1225
1226 /* We make a separate list of devices because the unregister_netdev()
1227 * will call device_event() which will also want to modify the same
1228 * devices list.
1229 */
1230
1231 rcu_read_lock();
1232
1233 list_for_each_entry_rcu(entry, &bt_6lowpan_devices, list) {
1234 new_dev = kmalloc(sizeof(*new_dev), GFP_ATOMIC);
1235 if (!new_dev)
1236 break;
1237
1238 new_dev->netdev = entry->netdev;
1239 INIT_LIST_HEAD(&new_dev->list);
1240
1241 list_add_rcu(&new_dev->list, &devices);
1242 }
1243
1244 rcu_read_unlock();
1245
1246 list_for_each_entry_safe(entry, tmp, &devices, list) {
1247 ifdown(entry->netdev);
1248 BT_DBG("Unregistering netdev %s %p",
1249 entry->netdev->name, entry->netdev);
1250 lowpan_unregister_netdev(entry->netdev);
1251 kfree(entry);
1252 }
1253}
1254
1255static int device_event(struct notifier_block *unused,
1256 unsigned long event, void *ptr)
1257{
1258 struct net_device *netdev = netdev_notifier_info_to_dev(ptr);
1259 struct lowpan_btle_dev *entry;
1260
1261 if (netdev->type != ARPHRD_6LOWPAN)
1262 return NOTIFY_DONE;
1263
1264 switch (event) {
1265 case NETDEV_UNREGISTER:
1266 spin_lock(&devices_lock);
1267 list_for_each_entry(entry, &bt_6lowpan_devices, list) {
1268 if (entry->netdev == netdev) {
1269 BT_DBG("Unregistered netdev %s %p",
1270 netdev->name, netdev);
1271 list_del(&entry->list);
1272 break;
1273 }
1274 }
1275 spin_unlock(&devices_lock);
1276 break;
1277 }
1278
1279 return NOTIFY_DONE;
1280}
1281
1282static struct notifier_block bt_6lowpan_dev_notifier = {
1283 .notifier_call = device_event,
1284};
1285
1286static int __init bt_6lowpan_init(void)
1287{
1288 lowpan_enable_debugfs = debugfs_create_file_unsafe("6lowpan_enable",
1289 0644, bt_debugfs,
1290 NULL,
1291 &lowpan_enable_fops);
1292 lowpan_control_debugfs = debugfs_create_file("6lowpan_control", 0644,
1293 bt_debugfs, NULL,
1294 &lowpan_control_fops);
1295
1296 return register_netdevice_notifier(&bt_6lowpan_dev_notifier);
1297}
1298
1299static void __exit bt_6lowpan_exit(void)
1300{
1301 debugfs_remove(lowpan_enable_debugfs);
1302 debugfs_remove(lowpan_control_debugfs);
1303
1304 if (listen_chan) {
1305 l2cap_chan_close(listen_chan, 0);
1306 l2cap_chan_put(listen_chan);
1307 }
1308
1309 disconnect_devices();
1310
1311 unregister_netdevice_notifier(&bt_6lowpan_dev_notifier);
1312}
1313
1314module_init(bt_6lowpan_init);
1315module_exit(bt_6lowpan_exit);
1316
1317MODULE_AUTHOR("Jukka Rissanen <jukka.rissanen@linux.intel.com>");
1318MODULE_DESCRIPTION("Bluetooth 6LoWPAN");
1319MODULE_VERSION(VERSION);
1320MODULE_LICENSE("GPL");