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