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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;
53
54struct lowpan_peer {
55 struct list_head list;
56 struct rcu_head rcu;
57 struct l2cap_chan *chan;
58
59 /* peer addresses in various formats */
60 unsigned char lladdr[ETH_ALEN];
61 struct in6_addr peer_addr;
62};
63
64struct lowpan_btle_dev {
65 struct list_head list;
66
67 struct hci_dev *hdev;
68 struct net_device *netdev;
69 struct list_head peers;
70 atomic_t peer_count; /* number of items in peers list */
71
72 struct work_struct delete_netdev;
73 struct delayed_work notify_peers;
74};
75
76static inline struct lowpan_btle_dev *
77lowpan_btle_dev(const struct net_device *netdev)
78{
79 return (struct lowpan_btle_dev *)lowpan_dev(netdev)->priv;
80}
81
82static inline void peer_add(struct lowpan_btle_dev *dev,
83 struct lowpan_peer *peer)
84{
85 list_add_rcu(&peer->list, &dev->peers);
86 atomic_inc(&dev->peer_count);
87}
88
89static inline bool peer_del(struct lowpan_btle_dev *dev,
90 struct lowpan_peer *peer)
91{
92 list_del_rcu(&peer->list);
93 kfree_rcu(peer, rcu);
94
95 module_put(THIS_MODULE);
96
97 if (atomic_dec_and_test(&dev->peer_count)) {
98 BT_DBG("last peer");
99 return true;
100 }
101
102 return false;
103}
104
105static inline struct lowpan_peer *peer_lookup_ba(struct lowpan_btle_dev *dev,
106 bdaddr_t *ba, __u8 type)
107{
108 struct lowpan_peer *peer;
109
110 BT_DBG("peers %d addr %pMR type %d", atomic_read(&dev->peer_count),
111 ba, type);
112
113 rcu_read_lock();
114
115 list_for_each_entry_rcu(peer, &dev->peers, list) {
116 BT_DBG("dst addr %pMR dst type %d",
117 &peer->chan->dst, peer->chan->dst_type);
118
119 if (bacmp(&peer->chan->dst, ba))
120 continue;
121
122 if (type == peer->chan->dst_type) {
123 rcu_read_unlock();
124 return peer;
125 }
126 }
127
128 rcu_read_unlock();
129
130 return NULL;
131}
132
133static inline struct lowpan_peer *
134__peer_lookup_chan(struct lowpan_btle_dev *dev, struct l2cap_chan *chan)
135{
136 struct lowpan_peer *peer;
137
138 list_for_each_entry_rcu(peer, &dev->peers, list) {
139 if (peer->chan == chan)
140 return peer;
141 }
142
143 return NULL;
144}
145
146static inline struct lowpan_peer *
147__peer_lookup_conn(struct lowpan_btle_dev *dev, struct l2cap_conn *conn)
148{
149 struct lowpan_peer *peer;
150
151 list_for_each_entry_rcu(peer, &dev->peers, list) {
152 if (peer->chan->conn == conn)
153 return peer;
154 }
155
156 return NULL;
157}
158
159static inline struct lowpan_peer *peer_lookup_dst(struct lowpan_btle_dev *dev,
160 struct in6_addr *daddr,
161 struct sk_buff *skb)
162{
163 struct rt6_info *rt = (struct rt6_info *)skb_dst(skb);
164 int count = atomic_read(&dev->peer_count);
165 const struct in6_addr *nexthop;
166 struct lowpan_peer *peer;
167 struct neighbour *neigh;
168
169 BT_DBG("peers %d addr %pI6c rt %p", count, daddr, rt);
170
171 if (!rt) {
172 if (ipv6_addr_any(&lowpan_cb(skb)->gw)) {
173 /* There is neither route nor gateway,
174 * probably the destination is a direct peer.
175 */
176 nexthop = daddr;
177 } else {
178 /* There is a known gateway
179 */
180 nexthop = &lowpan_cb(skb)->gw;
181 }
182 } else {
183 nexthop = rt6_nexthop(rt, daddr);
184
185 /* We need to remember the address because it is needed
186 * by bt_xmit() when sending the packet. In bt_xmit(), the
187 * destination routing info is not set.
188 */
189 memcpy(&lowpan_cb(skb)->gw, nexthop, sizeof(struct in6_addr));
190 }
191
192 BT_DBG("gw %pI6c", nexthop);
193
194 rcu_read_lock();
195
196 list_for_each_entry_rcu(peer, &dev->peers, list) {
197 BT_DBG("dst addr %pMR dst type %d ip %pI6c",
198 &peer->chan->dst, peer->chan->dst_type,
199 &peer->peer_addr);
200
201 if (!ipv6_addr_cmp(&peer->peer_addr, nexthop)) {
202 rcu_read_unlock();
203 return peer;
204 }
205 }
206
207 /* use the neighbour cache for matching addresses assigned by SLAAC
208 */
209 neigh = __ipv6_neigh_lookup(dev->netdev, nexthop);
210 if (neigh) {
211 list_for_each_entry_rcu(peer, &dev->peers, list) {
212 if (!memcmp(neigh->ha, peer->lladdr, ETH_ALEN)) {
213 neigh_release(neigh);
214 rcu_read_unlock();
215 return peer;
216 }
217 }
218 neigh_release(neigh);
219 }
220
221 rcu_read_unlock();
222
223 return NULL;
224}
225
226static struct lowpan_peer *lookup_peer(struct l2cap_conn *conn)
227{
228 struct lowpan_btle_dev *entry;
229 struct lowpan_peer *peer = NULL;
230
231 rcu_read_lock();
232
233 list_for_each_entry_rcu(entry, &bt_6lowpan_devices, list) {
234 peer = __peer_lookup_conn(entry, conn);
235 if (peer)
236 break;
237 }
238
239 rcu_read_unlock();
240
241 return peer;
242}
243
244static struct lowpan_btle_dev *lookup_dev(struct l2cap_conn *conn)
245{
246 struct lowpan_btle_dev *entry;
247 struct lowpan_btle_dev *dev = NULL;
248
249 rcu_read_lock();
250
251 list_for_each_entry_rcu(entry, &bt_6lowpan_devices, list) {
252 if (conn->hcon->hdev == entry->hdev) {
253 dev = entry;
254 break;
255 }
256 }
257
258 rcu_read_unlock();
259
260 return dev;
261}
262
263static int give_skb_to_upper(struct sk_buff *skb, struct net_device *dev)
264{
265 struct sk_buff *skb_cp;
266
267 skb_cp = skb_copy(skb, GFP_ATOMIC);
268 if (!skb_cp)
269 return NET_RX_DROP;
270
271 return netif_rx_ni(skb_cp);
272}
273
274static int iphc_decompress(struct sk_buff *skb, struct net_device *netdev,
275 struct lowpan_peer *peer)
276{
277 const u8 *saddr;
278
279 saddr = peer->lladdr;
280
281 return lowpan_header_decompress(skb, netdev, netdev->dev_addr, saddr);
282}
283
284static int recv_pkt(struct sk_buff *skb, struct net_device *dev,
285 struct lowpan_peer *peer)
286{
287 struct sk_buff *local_skb;
288 int ret;
289
290 if (!netif_running(dev))
291 goto drop;
292
293 if (dev->type != ARPHRD_6LOWPAN || !skb->len)
294 goto drop;
295
296 skb_reset_network_header(skb);
297
298 skb = skb_share_check(skb, GFP_ATOMIC);
299 if (!skb)
300 goto drop;
301
302 /* check that it's our buffer */
303 if (lowpan_is_ipv6(*skb_network_header(skb))) {
304 /* Pull off the 1-byte of 6lowpan header. */
305 skb_pull(skb, 1);
306
307 /* Copy the packet so that the IPv6 header is
308 * properly aligned.
309 */
310 local_skb = skb_copy_expand(skb, NET_SKB_PAD - 1,
311 skb_tailroom(skb), GFP_ATOMIC);
312 if (!local_skb)
313 goto drop;
314
315 local_skb->protocol = htons(ETH_P_IPV6);
316 local_skb->pkt_type = PACKET_HOST;
317 local_skb->dev = dev;
318
319 skb_set_transport_header(local_skb, sizeof(struct ipv6hdr));
320
321 if (give_skb_to_upper(local_skb, dev) != 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 if (lowpan_is_iphc(*skb_network_header(skb))) {
332 local_skb = skb_clone(skb, GFP_ATOMIC);
333 if (!local_skb)
334 goto drop;
335
336 local_skb->dev = dev;
337
338 ret = iphc_decompress(local_skb, dev, peer);
339 if (ret < 0) {
340 BT_DBG("iphc_decompress failed: %d", ret);
341 kfree_skb(local_skb);
342 goto drop;
343 }
344
345 local_skb->protocol = htons(ETH_P_IPV6);
346 local_skb->pkt_type = PACKET_HOST;
347
348 if (give_skb_to_upper(local_skb, dev)
349 != NET_RX_SUCCESS) {
350 kfree_skb(local_skb);
351 goto drop;
352 }
353
354 dev->stats.rx_bytes += skb->len;
355 dev->stats.rx_packets++;
356
357 consume_skb(local_skb);
358 consume_skb(skb);
359 } else {
360 BT_DBG("unknown packet type");
361 goto drop;
362 }
363
364 return NET_RX_SUCCESS;
365
366drop:
367 dev->stats.rx_dropped++;
368 return NET_RX_DROP;
369}
370
371/* Packet from BT LE device */
372static int chan_recv_cb(struct l2cap_chan *chan, struct sk_buff *skb)
373{
374 struct lowpan_btle_dev *dev;
375 struct lowpan_peer *peer;
376 int err;
377
378 peer = lookup_peer(chan->conn);
379 if (!peer)
380 return -ENOENT;
381
382 dev = lookup_dev(chan->conn);
383 if (!dev || !dev->netdev)
384 return -ENOENT;
385
386 err = recv_pkt(skb, dev->netdev, peer);
387 if (err) {
388 BT_DBG("recv pkt %d", err);
389 err = -EAGAIN;
390 }
391
392 return err;
393}
394
395static int setup_header(struct sk_buff *skb, struct net_device *netdev,
396 bdaddr_t *peer_addr, u8 *peer_addr_type)
397{
398 struct in6_addr ipv6_daddr;
399 struct ipv6hdr *hdr;
400 struct lowpan_btle_dev *dev;
401 struct lowpan_peer *peer;
402 u8 *daddr;
403 int err, status = 0;
404
405 hdr = ipv6_hdr(skb);
406
407 dev = lowpan_btle_dev(netdev);
408
409 memcpy(&ipv6_daddr, &hdr->daddr, sizeof(ipv6_daddr));
410
411 if (ipv6_addr_is_multicast(&ipv6_daddr)) {
412 lowpan_cb(skb)->chan = NULL;
413 daddr = NULL;
414 } else {
415 BT_DBG("dest IP %pI6c", &ipv6_daddr);
416
417 /* The packet might be sent to 6lowpan interface
418 * because of routing (either via default route
419 * or user set route) so get peer according to
420 * the destination address.
421 */
422 peer = peer_lookup_dst(dev, &ipv6_daddr, skb);
423 if (!peer) {
424 BT_DBG("no such peer");
425 return -ENOENT;
426 }
427
428 daddr = peer->lladdr;
429 *peer_addr = peer->chan->dst;
430 *peer_addr_type = peer->chan->dst_type;
431 lowpan_cb(skb)->chan = peer->chan;
432
433 status = 1;
434 }
435
436 lowpan_header_compress(skb, netdev, daddr, dev->netdev->dev_addr);
437
438 err = dev_hard_header(skb, netdev, ETH_P_IPV6, NULL, NULL, 0);
439 if (err < 0)
440 return err;
441
442 return status;
443}
444
445static int header_create(struct sk_buff *skb, struct net_device *netdev,
446 unsigned short type, const void *_daddr,
447 const void *_saddr, unsigned int len)
448{
449 if (type != ETH_P_IPV6)
450 return -EINVAL;
451
452 return 0;
453}
454
455/* Packet to BT LE device */
456static int send_pkt(struct l2cap_chan *chan, struct sk_buff *skb,
457 struct net_device *netdev)
458{
459 struct msghdr msg;
460 struct kvec iv;
461 int err;
462
463 /* Remember the skb so that we can send EAGAIN to the caller if
464 * we run out of credits.
465 */
466 chan->data = skb;
467
468 iv.iov_base = skb->data;
469 iv.iov_len = skb->len;
470
471 memset(&msg, 0, sizeof(msg));
472 iov_iter_kvec(&msg.msg_iter, WRITE, &iv, 1, skb->len);
473
474 err = l2cap_chan_send(chan, &msg, skb->len);
475 if (err > 0) {
476 netdev->stats.tx_bytes += err;
477 netdev->stats.tx_packets++;
478 return 0;
479 }
480
481 if (err < 0)
482 netdev->stats.tx_errors++;
483
484 return err;
485}
486
487static int send_mcast_pkt(struct sk_buff *skb, struct net_device *netdev)
488{
489 struct sk_buff *local_skb;
490 struct lowpan_btle_dev *entry;
491 int err = 0;
492
493 rcu_read_lock();
494
495 list_for_each_entry_rcu(entry, &bt_6lowpan_devices, list) {
496 struct lowpan_peer *pentry;
497 struct lowpan_btle_dev *dev;
498
499 if (entry->netdev != netdev)
500 continue;
501
502 dev = lowpan_btle_dev(entry->netdev);
503
504 list_for_each_entry_rcu(pentry, &dev->peers, list) {
505 int ret;
506
507 local_skb = skb_clone(skb, GFP_ATOMIC);
508
509 BT_DBG("xmit %s to %pMR type %d IP %pI6c chan %p",
510 netdev->name,
511 &pentry->chan->dst, pentry->chan->dst_type,
512 &pentry->peer_addr, pentry->chan);
513 ret = send_pkt(pentry->chan, local_skb, netdev);
514 if (ret < 0)
515 err = ret;
516
517 kfree_skb(local_skb);
518 }
519 }
520
521 rcu_read_unlock();
522
523 return err;
524}
525
526static netdev_tx_t bt_xmit(struct sk_buff *skb, struct net_device *netdev)
527{
528 int err = 0;
529 bdaddr_t addr;
530 u8 addr_type;
531
532 /* We must take a copy of the skb before we modify/replace the ipv6
533 * header as the header could be used elsewhere
534 */
535 skb = skb_unshare(skb, GFP_ATOMIC);
536 if (!skb)
537 return NET_XMIT_DROP;
538
539 /* Return values from setup_header()
540 * <0 - error, packet is dropped
541 * 0 - this is a multicast packet
542 * 1 - this is unicast packet
543 */
544 err = setup_header(skb, netdev, &addr, &addr_type);
545 if (err < 0) {
546 kfree_skb(skb);
547 return NET_XMIT_DROP;
548 }
549
550 if (err) {
551 if (lowpan_cb(skb)->chan) {
552 BT_DBG("xmit %s to %pMR type %d IP %pI6c chan %p",
553 netdev->name, &addr, addr_type,
554 &lowpan_cb(skb)->addr, lowpan_cb(skb)->chan);
555 err = send_pkt(lowpan_cb(skb)->chan, skb, netdev);
556 } else {
557 err = -ENOENT;
558 }
559 } else {
560 /* We need to send the packet to every device behind this
561 * interface.
562 */
563 err = send_mcast_pkt(skb, netdev);
564 }
565
566 dev_kfree_skb(skb);
567
568 if (err)
569 BT_DBG("ERROR: xmit failed (%d)", err);
570
571 return err < 0 ? NET_XMIT_DROP : err;
572}
573
574static const struct net_device_ops netdev_ops = {
575 .ndo_start_xmit = bt_xmit,
576};
577
578static const struct header_ops header_ops = {
579 .create = header_create,
580};
581
582static void netdev_setup(struct net_device *dev)
583{
584 dev->hard_header_len = 0;
585 dev->needed_tailroom = 0;
586 dev->flags = IFF_RUNNING | IFF_MULTICAST;
587 dev->watchdog_timeo = 0;
588 dev->tx_queue_len = DEFAULT_TX_QUEUE_LEN;
589
590 dev->netdev_ops = &netdev_ops;
591 dev->header_ops = &header_ops;
592 dev->needs_free_netdev = true;
593}
594
595static struct device_type bt_type = {
596 .name = "bluetooth",
597};
598
599static void ifup(struct net_device *netdev)
600{
601 int err;
602
603 rtnl_lock();
604 err = dev_open(netdev, NULL);
605 if (err < 0)
606 BT_INFO("iface %s cannot be opened (%d)", netdev->name, err);
607 rtnl_unlock();
608}
609
610static void ifdown(struct net_device *netdev)
611{
612 rtnl_lock();
613 dev_close(netdev);
614 rtnl_unlock();
615}
616
617static void do_notify_peers(struct work_struct *work)
618{
619 struct lowpan_btle_dev *dev = container_of(work, struct lowpan_btle_dev,
620 notify_peers.work);
621
622 netdev_notify_peers(dev->netdev); /* send neighbour adv at startup */
623}
624
625static bool is_bt_6lowpan(struct hci_conn *hcon)
626{
627 if (hcon->type != LE_LINK)
628 return false;
629
630 if (!enable_6lowpan)
631 return false;
632
633 return true;
634}
635
636static struct l2cap_chan *chan_create(void)
637{
638 struct l2cap_chan *chan;
639
640 chan = l2cap_chan_create();
641 if (!chan)
642 return NULL;
643
644 l2cap_chan_set_defaults(chan);
645
646 chan->chan_type = L2CAP_CHAN_CONN_ORIENTED;
647 chan->mode = L2CAP_MODE_LE_FLOWCTL;
648 chan->imtu = 1280;
649
650 return chan;
651}
652
653static struct l2cap_chan *add_peer_chan(struct l2cap_chan *chan,
654 struct lowpan_btle_dev *dev,
655 bool new_netdev)
656{
657 struct lowpan_peer *peer;
658
659 peer = kzalloc(sizeof(*peer), GFP_ATOMIC);
660 if (!peer)
661 return NULL;
662
663 peer->chan = chan;
664 memset(&peer->peer_addr, 0, sizeof(struct in6_addr));
665
666 baswap((void *)peer->lladdr, &chan->dst);
667
668 lowpan_iphc_uncompress_eui48_lladdr(&peer->peer_addr, peer->lladdr);
669
670 spin_lock(&devices_lock);
671 INIT_LIST_HEAD(&peer->list);
672 peer_add(dev, peer);
673 spin_unlock(&devices_lock);
674
675 /* Notifying peers about us needs to be done without locks held */
676 if (new_netdev)
677 INIT_DELAYED_WORK(&dev->notify_peers, do_notify_peers);
678 schedule_delayed_work(&dev->notify_peers, msecs_to_jiffies(100));
679
680 return peer->chan;
681}
682
683static int setup_netdev(struct l2cap_chan *chan, struct lowpan_btle_dev **dev)
684{
685 struct net_device *netdev;
686 int err = 0;
687
688 netdev = alloc_netdev(LOWPAN_PRIV_SIZE(sizeof(struct lowpan_btle_dev)),
689 IFACE_NAME_TEMPLATE, NET_NAME_UNKNOWN,
690 netdev_setup);
691 if (!netdev)
692 return -ENOMEM;
693
694 netdev->addr_assign_type = NET_ADDR_PERM;
695 baswap((void *)netdev->dev_addr, &chan->src);
696
697 netdev->netdev_ops = &netdev_ops;
698 SET_NETDEV_DEV(netdev, &chan->conn->hcon->hdev->dev);
699 SET_NETDEV_DEVTYPE(netdev, &bt_type);
700
701 *dev = lowpan_btle_dev(netdev);
702 (*dev)->netdev = netdev;
703 (*dev)->hdev = chan->conn->hcon->hdev;
704 INIT_LIST_HEAD(&(*dev)->peers);
705
706 spin_lock(&devices_lock);
707 INIT_LIST_HEAD(&(*dev)->list);
708 list_add_rcu(&(*dev)->list, &bt_6lowpan_devices);
709 spin_unlock(&devices_lock);
710
711 err = lowpan_register_netdev(netdev, LOWPAN_LLTYPE_BTLE);
712 if (err < 0) {
713 BT_INFO("register_netdev failed %d", err);
714 spin_lock(&devices_lock);
715 list_del_rcu(&(*dev)->list);
716 spin_unlock(&devices_lock);
717 free_netdev(netdev);
718 goto out;
719 }
720
721 BT_DBG("ifindex %d peer bdaddr %pMR type %d my addr %pMR type %d",
722 netdev->ifindex, &chan->dst, chan->dst_type,
723 &chan->src, chan->src_type);
724 set_bit(__LINK_STATE_PRESENT, &netdev->state);
725
726 return 0;
727
728out:
729 return err;
730}
731
732static inline void chan_ready_cb(struct l2cap_chan *chan)
733{
734 struct lowpan_btle_dev *dev;
735 bool new_netdev = false;
736
737 dev = lookup_dev(chan->conn);
738
739 BT_DBG("chan %p conn %p dev %p", chan, chan->conn, dev);
740
741 if (!dev) {
742 if (setup_netdev(chan, &dev) < 0) {
743 l2cap_chan_del(chan, -ENOENT);
744 return;
745 }
746 new_netdev = true;
747 }
748
749 if (!try_module_get(THIS_MODULE))
750 return;
751
752 add_peer_chan(chan, dev, new_netdev);
753 ifup(dev->netdev);
754}
755
756static inline struct l2cap_chan *chan_new_conn_cb(struct l2cap_chan *pchan)
757{
758 struct l2cap_chan *chan;
759
760 chan = chan_create();
761 if (!chan)
762 return NULL;
763
764 chan->ops = pchan->ops;
765
766 BT_DBG("chan %p pchan %p", chan, pchan);
767
768 return chan;
769}
770
771static void delete_netdev(struct work_struct *work)
772{
773 struct lowpan_btle_dev *entry = container_of(work,
774 struct lowpan_btle_dev,
775 delete_netdev);
776
777 lowpan_unregister_netdev(entry->netdev);
778
779 /* The entry pointer is deleted by the netdev destructor. */
780}
781
782static void chan_close_cb(struct l2cap_chan *chan)
783{
784 struct lowpan_btle_dev *entry;
785 struct lowpan_btle_dev *dev = NULL;
786 struct lowpan_peer *peer;
787 int err = -ENOENT;
788 bool last = false, remove = true;
789
790 BT_DBG("chan %p conn %p", chan, chan->conn);
791
792 if (chan->conn && chan->conn->hcon) {
793 if (!is_bt_6lowpan(chan->conn->hcon))
794 return;
795
796 /* If conn is set, then the netdev is also there and we should
797 * not remove it.
798 */
799 remove = false;
800 }
801
802 spin_lock(&devices_lock);
803
804 list_for_each_entry_rcu(entry, &bt_6lowpan_devices, list) {
805 dev = lowpan_btle_dev(entry->netdev);
806 peer = __peer_lookup_chan(dev, chan);
807 if (peer) {
808 last = peer_del(dev, peer);
809 err = 0;
810
811 BT_DBG("dev %p removing %speer %p", dev,
812 last ? "last " : "1 ", peer);
813 BT_DBG("chan %p orig refcnt %d", chan,
814 kref_read(&chan->kref));
815
816 l2cap_chan_put(chan);
817 break;
818 }
819 }
820
821 if (!err && last && dev && !atomic_read(&dev->peer_count)) {
822 spin_unlock(&devices_lock);
823
824 cancel_delayed_work_sync(&dev->notify_peers);
825
826 ifdown(dev->netdev);
827
828 if (remove) {
829 INIT_WORK(&entry->delete_netdev, delete_netdev);
830 schedule_work(&entry->delete_netdev);
831 }
832 } else {
833 spin_unlock(&devices_lock);
834 }
835
836 return;
837}
838
839static void chan_state_change_cb(struct l2cap_chan *chan, int state, int err)
840{
841 BT_DBG("chan %p conn %p state %s err %d", chan, chan->conn,
842 state_to_string(state), err);
843}
844
845static struct sk_buff *chan_alloc_skb_cb(struct l2cap_chan *chan,
846 unsigned long hdr_len,
847 unsigned long len, int nb)
848{
849 /* Note that we must allocate using GFP_ATOMIC here as
850 * this function is called originally from netdev hard xmit
851 * function in atomic context.
852 */
853 return bt_skb_alloc(hdr_len + len, GFP_ATOMIC);
854}
855
856static void chan_suspend_cb(struct l2cap_chan *chan)
857{
858 struct lowpan_btle_dev *dev;
859
860 BT_DBG("chan %p suspend", chan);
861
862 dev = lookup_dev(chan->conn);
863 if (!dev || !dev->netdev)
864 return;
865
866 netif_stop_queue(dev->netdev);
867}
868
869static void chan_resume_cb(struct l2cap_chan *chan)
870{
871 struct lowpan_btle_dev *dev;
872
873 BT_DBG("chan %p resume", chan);
874
875 dev = lookup_dev(chan->conn);
876 if (!dev || !dev->netdev)
877 return;
878
879 netif_wake_queue(dev->netdev);
880}
881
882static long chan_get_sndtimeo_cb(struct l2cap_chan *chan)
883{
884 return L2CAP_CONN_TIMEOUT;
885}
886
887static const struct l2cap_ops bt_6lowpan_chan_ops = {
888 .name = "L2CAP 6LoWPAN channel",
889 .new_connection = chan_new_conn_cb,
890 .recv = chan_recv_cb,
891 .close = chan_close_cb,
892 .state_change = chan_state_change_cb,
893 .ready = chan_ready_cb,
894 .resume = chan_resume_cb,
895 .suspend = chan_suspend_cb,
896 .get_sndtimeo = chan_get_sndtimeo_cb,
897 .alloc_skb = chan_alloc_skb_cb,
898
899 .teardown = l2cap_chan_no_teardown,
900 .defer = l2cap_chan_no_defer,
901 .set_shutdown = l2cap_chan_no_set_shutdown,
902};
903
904static inline __u8 bdaddr_type(__u8 type)
905{
906 if (type == ADDR_LE_DEV_PUBLIC)
907 return BDADDR_LE_PUBLIC;
908 else
909 return BDADDR_LE_RANDOM;
910}
911
912static int bt_6lowpan_connect(bdaddr_t *addr, u8 dst_type)
913{
914 struct l2cap_chan *chan;
915 int err;
916
917 chan = chan_create();
918 if (!chan)
919 return -EINVAL;
920
921 chan->ops = &bt_6lowpan_chan_ops;
922
923 err = l2cap_chan_connect(chan, cpu_to_le16(L2CAP_PSM_IPSP), 0,
924 addr, dst_type);
925
926 BT_DBG("chan %p err %d", chan, err);
927 if (err < 0)
928 l2cap_chan_put(chan);
929
930 return err;
931}
932
933static int bt_6lowpan_disconnect(struct l2cap_conn *conn, u8 dst_type)
934{
935 struct lowpan_peer *peer;
936
937 BT_DBG("conn %p dst type %d", conn, dst_type);
938
939 peer = lookup_peer(conn);
940 if (!peer)
941 return -ENOENT;
942
943 BT_DBG("peer %p chan %p", peer, peer->chan);
944
945 l2cap_chan_close(peer->chan, ENOENT);
946
947 return 0;
948}
949
950static struct l2cap_chan *bt_6lowpan_listen(void)
951{
952 bdaddr_t *addr = BDADDR_ANY;
953 struct l2cap_chan *chan;
954 int err;
955
956 if (!enable_6lowpan)
957 return NULL;
958
959 chan = chan_create();
960 if (!chan)
961 return NULL;
962
963 chan->ops = &bt_6lowpan_chan_ops;
964 chan->state = BT_LISTEN;
965 chan->src_type = BDADDR_LE_PUBLIC;
966
967 atomic_set(&chan->nesting, L2CAP_NESTING_PARENT);
968
969 BT_DBG("chan %p src type %d", chan, chan->src_type);
970
971 err = l2cap_add_psm(chan, addr, cpu_to_le16(L2CAP_PSM_IPSP));
972 if (err) {
973 l2cap_chan_put(chan);
974 BT_ERR("psm cannot be added err %d", err);
975 return NULL;
976 }
977
978 return chan;
979}
980
981static int get_l2cap_conn(char *buf, bdaddr_t *addr, u8 *addr_type,
982 struct l2cap_conn **conn)
983{
984 struct hci_conn *hcon;
985 struct hci_dev *hdev;
986 int n;
987
988 n = sscanf(buf, "%hhx:%hhx:%hhx:%hhx:%hhx:%hhx %hhu",
989 &addr->b[5], &addr->b[4], &addr->b[3],
990 &addr->b[2], &addr->b[1], &addr->b[0],
991 addr_type);
992
993 if (n < 7)
994 return -EINVAL;
995
996 /* The LE_PUBLIC address type is ignored because of BDADDR_ANY */
997 hdev = hci_get_route(addr, BDADDR_ANY, BDADDR_LE_PUBLIC);
998 if (!hdev)
999 return -ENOENT;
1000
1001 hci_dev_lock(hdev);
1002 hcon = hci_conn_hash_lookup_le(hdev, addr, *addr_type);
1003 hci_dev_unlock(hdev);
1004
1005 if (!hcon)
1006 return -ENOENT;
1007
1008 *conn = (struct l2cap_conn *)hcon->l2cap_data;
1009
1010 BT_DBG("conn %p dst %pMR type %d", *conn, &hcon->dst, hcon->dst_type);
1011
1012 return 0;
1013}
1014
1015static void disconnect_all_peers(void)
1016{
1017 struct lowpan_btle_dev *entry;
1018 struct lowpan_peer *peer, *tmp_peer, *new_peer;
1019 struct list_head peers;
1020
1021 INIT_LIST_HEAD(&peers);
1022
1023 /* We make a separate list of peers as the close_cb() will
1024 * modify the device peers list so it is better not to mess
1025 * with the same list at the same time.
1026 */
1027
1028 rcu_read_lock();
1029
1030 list_for_each_entry_rcu(entry, &bt_6lowpan_devices, list) {
1031 list_for_each_entry_rcu(peer, &entry->peers, list) {
1032 new_peer = kmalloc(sizeof(*new_peer), GFP_ATOMIC);
1033 if (!new_peer)
1034 break;
1035
1036 new_peer->chan = peer->chan;
1037 INIT_LIST_HEAD(&new_peer->list);
1038
1039 list_add(&new_peer->list, &peers);
1040 }
1041 }
1042
1043 rcu_read_unlock();
1044
1045 spin_lock(&devices_lock);
1046 list_for_each_entry_safe(peer, tmp_peer, &peers, list) {
1047 l2cap_chan_close(peer->chan, ENOENT);
1048
1049 list_del_rcu(&peer->list);
1050 kfree_rcu(peer, rcu);
1051 }
1052 spin_unlock(&devices_lock);
1053}
1054
1055struct set_enable {
1056 struct work_struct work;
1057 bool flag;
1058};
1059
1060static void do_enable_set(struct work_struct *work)
1061{
1062 struct set_enable *set_enable = container_of(work,
1063 struct set_enable, work);
1064
1065 if (!set_enable->flag || enable_6lowpan != set_enable->flag)
1066 /* Disconnect existing connections if 6lowpan is
1067 * disabled
1068 */
1069 disconnect_all_peers();
1070
1071 enable_6lowpan = set_enable->flag;
1072
1073 if (listen_chan) {
1074 l2cap_chan_close(listen_chan, 0);
1075 l2cap_chan_put(listen_chan);
1076 }
1077
1078 listen_chan = bt_6lowpan_listen();
1079
1080 kfree(set_enable);
1081}
1082
1083static int lowpan_enable_set(void *data, u64 val)
1084{
1085 struct set_enable *set_enable;
1086
1087 set_enable = kzalloc(sizeof(*set_enable), GFP_KERNEL);
1088 if (!set_enable)
1089 return -ENOMEM;
1090
1091 set_enable->flag = !!val;
1092 INIT_WORK(&set_enable->work, do_enable_set);
1093
1094 schedule_work(&set_enable->work);
1095
1096 return 0;
1097}
1098
1099static int lowpan_enable_get(void *data, u64 *val)
1100{
1101 *val = enable_6lowpan;
1102 return 0;
1103}
1104
1105DEFINE_DEBUGFS_ATTRIBUTE(lowpan_enable_fops, lowpan_enable_get,
1106 lowpan_enable_set, "%llu\n");
1107
1108static ssize_t lowpan_control_write(struct file *fp,
1109 const char __user *user_buffer,
1110 size_t count,
1111 loff_t *position)
1112{
1113 char buf[32];
1114 size_t buf_size = min(count, sizeof(buf) - 1);
1115 int ret;
1116 bdaddr_t addr;
1117 u8 addr_type;
1118 struct l2cap_conn *conn = NULL;
1119
1120 if (copy_from_user(buf, user_buffer, buf_size))
1121 return -EFAULT;
1122
1123 buf[buf_size] = '\0';
1124
1125 if (memcmp(buf, "connect ", 8) == 0) {
1126 ret = get_l2cap_conn(&buf[8], &addr, &addr_type, &conn);
1127 if (ret == -EINVAL)
1128 return ret;
1129
1130 if (listen_chan) {
1131 l2cap_chan_close(listen_chan, 0);
1132 l2cap_chan_put(listen_chan);
1133 listen_chan = NULL;
1134 }
1135
1136 if (conn) {
1137 struct lowpan_peer *peer;
1138
1139 if (!is_bt_6lowpan(conn->hcon))
1140 return -EINVAL;
1141
1142 peer = lookup_peer(conn);
1143 if (peer) {
1144 BT_DBG("6LoWPAN connection already exists");
1145 return -EALREADY;
1146 }
1147
1148 BT_DBG("conn %p dst %pMR type %d user %d", conn,
1149 &conn->hcon->dst, conn->hcon->dst_type,
1150 addr_type);
1151 }
1152
1153 ret = bt_6lowpan_connect(&addr, addr_type);
1154 if (ret < 0)
1155 return ret;
1156
1157 return count;
1158 }
1159
1160 if (memcmp(buf, "disconnect ", 11) == 0) {
1161 ret = get_l2cap_conn(&buf[11], &addr, &addr_type, &conn);
1162 if (ret < 0)
1163 return ret;
1164
1165 ret = bt_6lowpan_disconnect(conn, addr_type);
1166 if (ret < 0)
1167 return ret;
1168
1169 return count;
1170 }
1171
1172 return count;
1173}
1174
1175static int lowpan_control_show(struct seq_file *f, void *ptr)
1176{
1177 struct lowpan_btle_dev *entry;
1178 struct lowpan_peer *peer;
1179
1180 spin_lock(&devices_lock);
1181
1182 list_for_each_entry(entry, &bt_6lowpan_devices, list) {
1183 list_for_each_entry(peer, &entry->peers, list)
1184 seq_printf(f, "%pMR (type %u)\n",
1185 &peer->chan->dst, peer->chan->dst_type);
1186 }
1187
1188 spin_unlock(&devices_lock);
1189
1190 return 0;
1191}
1192
1193static int lowpan_control_open(struct inode *inode, struct file *file)
1194{
1195 return single_open(file, lowpan_control_show, inode->i_private);
1196}
1197
1198static const struct file_operations lowpan_control_fops = {
1199 .open = lowpan_control_open,
1200 .read = seq_read,
1201 .write = lowpan_control_write,
1202 .llseek = seq_lseek,
1203 .release = single_release,
1204};
1205
1206static void disconnect_devices(void)
1207{
1208 struct lowpan_btle_dev *entry, *tmp, *new_dev;
1209 struct list_head devices;
1210
1211 INIT_LIST_HEAD(&devices);
1212
1213 /* We make a separate list of devices because the unregister_netdev()
1214 * will call device_event() which will also want to modify the same
1215 * devices list.
1216 */
1217
1218 rcu_read_lock();
1219
1220 list_for_each_entry_rcu(entry, &bt_6lowpan_devices, list) {
1221 new_dev = kmalloc(sizeof(*new_dev), GFP_ATOMIC);
1222 if (!new_dev)
1223 break;
1224
1225 new_dev->netdev = entry->netdev;
1226 INIT_LIST_HEAD(&new_dev->list);
1227
1228 list_add_rcu(&new_dev->list, &devices);
1229 }
1230
1231 rcu_read_unlock();
1232
1233 list_for_each_entry_safe(entry, tmp, &devices, list) {
1234 ifdown(entry->netdev);
1235 BT_DBG("Unregistering netdev %s %p",
1236 entry->netdev->name, entry->netdev);
1237 lowpan_unregister_netdev(entry->netdev);
1238 kfree(entry);
1239 }
1240}
1241
1242static int device_event(struct notifier_block *unused,
1243 unsigned long event, void *ptr)
1244{
1245 struct net_device *netdev = netdev_notifier_info_to_dev(ptr);
1246 struct lowpan_btle_dev *entry;
1247
1248 if (netdev->type != ARPHRD_6LOWPAN)
1249 return NOTIFY_DONE;
1250
1251 switch (event) {
1252 case NETDEV_UNREGISTER:
1253 spin_lock(&devices_lock);
1254 list_for_each_entry(entry, &bt_6lowpan_devices, list) {
1255 if (entry->netdev == netdev) {
1256 BT_DBG("Unregistered netdev %s %p",
1257 netdev->name, netdev);
1258 list_del(&entry->list);
1259 break;
1260 }
1261 }
1262 spin_unlock(&devices_lock);
1263 break;
1264 }
1265
1266 return NOTIFY_DONE;
1267}
1268
1269static struct notifier_block bt_6lowpan_dev_notifier = {
1270 .notifier_call = device_event,
1271};
1272
1273static int __init bt_6lowpan_init(void)
1274{
1275 lowpan_enable_debugfs = debugfs_create_file_unsafe("6lowpan_enable",
1276 0644, bt_debugfs,
1277 NULL,
1278 &lowpan_enable_fops);
1279 lowpan_control_debugfs = debugfs_create_file("6lowpan_control", 0644,
1280 bt_debugfs, NULL,
1281 &lowpan_control_fops);
1282
1283 return register_netdevice_notifier(&bt_6lowpan_dev_notifier);
1284}
1285
1286static void __exit bt_6lowpan_exit(void)
1287{
1288 debugfs_remove(lowpan_enable_debugfs);
1289 debugfs_remove(lowpan_control_debugfs);
1290
1291 if (listen_chan) {
1292 l2cap_chan_close(listen_chan, 0);
1293 l2cap_chan_put(listen_chan);
1294 }
1295
1296 disconnect_devices();
1297
1298 unregister_netdevice_notifier(&bt_6lowpan_dev_notifier);
1299}
1300
1301module_init(bt_6lowpan_init);
1302module_exit(bt_6lowpan_exit);
1303
1304MODULE_AUTHOR("Jukka Rissanen <jukka.rissanen@linux.intel.com>");
1305MODULE_DESCRIPTION("Bluetooth 6LoWPAN");
1306MODULE_VERSION(VERSION);
1307MODULE_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
24#include <net/bluetooth/bluetooth.h>
25#include <net/bluetooth/hci_core.h>
26#include <net/bluetooth/l2cap.h>
27
28#include <net/6lowpan.h> /* for the compression support */
29
30#define VERSION "0.1"
31
32static struct dentry *lowpan_enable_debugfs;
33static struct dentry *lowpan_control_debugfs;
34
35#define IFACE_NAME_TEMPLATE "bt%d"
36
37struct skb_cb {
38 struct in6_addr addr;
39 struct in6_addr gw;
40 struct l2cap_chan *chan;
41 int status;
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 eui64_addr[EUI64_ADDR_LEN];
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 l2cap_chan *chan)
274{
275 const u8 *saddr, *daddr;
276 struct lowpan_btle_dev *dev;
277 struct lowpan_peer *peer;
278
279 dev = lowpan_btle_dev(netdev);
280
281 rcu_read_lock();
282 peer = __peer_lookup_chan(dev, chan);
283 rcu_read_unlock();
284 if (!peer)
285 return -EINVAL;
286
287 saddr = peer->eui64_addr;
288 daddr = dev->netdev->dev_addr;
289
290 return lowpan_header_decompress(skb, netdev, daddr, saddr);
291}
292
293static int recv_pkt(struct sk_buff *skb, struct net_device *dev,
294 struct l2cap_chan *chan)
295{
296 struct sk_buff *local_skb;
297 int ret;
298
299 if (!netif_running(dev))
300 goto drop;
301
302 if (dev->type != ARPHRD_6LOWPAN || !skb->len)
303 goto drop;
304
305 skb_reset_network_header(skb);
306
307 skb = skb_share_check(skb, GFP_ATOMIC);
308 if (!skb)
309 goto drop;
310
311 /* check that it's our buffer */
312 if (lowpan_is_ipv6(*skb_network_header(skb))) {
313 /* Pull off the 1-byte of 6lowpan header. */
314 skb_pull(skb, 1);
315
316 /* Copy the packet so that the IPv6 header is
317 * properly aligned.
318 */
319 local_skb = skb_copy_expand(skb, NET_SKB_PAD - 1,
320 skb_tailroom(skb), GFP_ATOMIC);
321 if (!local_skb)
322 goto drop;
323
324 local_skb->protocol = htons(ETH_P_IPV6);
325 local_skb->pkt_type = PACKET_HOST;
326 local_skb->dev = dev;
327
328 skb_set_transport_header(local_skb, sizeof(struct ipv6hdr));
329
330 if (give_skb_to_upper(local_skb, dev) != NET_RX_SUCCESS) {
331 kfree_skb(local_skb);
332 goto drop;
333 }
334
335 dev->stats.rx_bytes += skb->len;
336 dev->stats.rx_packets++;
337
338 consume_skb(local_skb);
339 consume_skb(skb);
340 } else if (lowpan_is_iphc(*skb_network_header(skb))) {
341 local_skb = skb_clone(skb, GFP_ATOMIC);
342 if (!local_skb)
343 goto drop;
344
345 local_skb->dev = dev;
346
347 ret = iphc_decompress(local_skb, dev, chan);
348 if (ret < 0) {
349 kfree_skb(local_skb);
350 goto drop;
351 }
352
353 local_skb->protocol = htons(ETH_P_IPV6);
354 local_skb->pkt_type = PACKET_HOST;
355
356 if (give_skb_to_upper(local_skb, dev)
357 != NET_RX_SUCCESS) {
358 kfree_skb(local_skb);
359 goto drop;
360 }
361
362 dev->stats.rx_bytes += skb->len;
363 dev->stats.rx_packets++;
364
365 consume_skb(local_skb);
366 consume_skb(skb);
367 } else {
368 goto drop;
369 }
370
371 return NET_RX_SUCCESS;
372
373drop:
374 dev->stats.rx_dropped++;
375 return NET_RX_DROP;
376}
377
378/* Packet from BT LE device */
379static int chan_recv_cb(struct l2cap_chan *chan, struct sk_buff *skb)
380{
381 struct lowpan_btle_dev *dev;
382 struct lowpan_peer *peer;
383 int err;
384
385 peer = lookup_peer(chan->conn);
386 if (!peer)
387 return -ENOENT;
388
389 dev = lookup_dev(chan->conn);
390 if (!dev || !dev->netdev)
391 return -ENOENT;
392
393 err = recv_pkt(skb, dev->netdev, chan);
394 if (err) {
395 BT_DBG("recv pkt %d", err);
396 err = -EAGAIN;
397 }
398
399 return err;
400}
401
402static u8 get_addr_type_from_eui64(u8 byte)
403{
404 /* Is universal(0) or local(1) bit */
405 return ((byte & 0x02) ? BDADDR_LE_RANDOM : BDADDR_LE_PUBLIC);
406}
407
408static void copy_to_bdaddr(struct in6_addr *ip6_daddr, bdaddr_t *addr)
409{
410 u8 *eui64 = ip6_daddr->s6_addr + 8;
411
412 addr->b[0] = eui64[7];
413 addr->b[1] = eui64[6];
414 addr->b[2] = eui64[5];
415 addr->b[3] = eui64[2];
416 addr->b[4] = eui64[1];
417 addr->b[5] = eui64[0];
418}
419
420static void convert_dest_bdaddr(struct in6_addr *ip6_daddr,
421 bdaddr_t *addr, u8 *addr_type)
422{
423 copy_to_bdaddr(ip6_daddr, addr);
424
425 /* We need to toggle the U/L bit that we got from IPv6 address
426 * so that we get the proper address and type of the BD address.
427 */
428 addr->b[5] ^= 0x02;
429
430 *addr_type = get_addr_type_from_eui64(addr->b[5]);
431}
432
433static int setup_header(struct sk_buff *skb, struct net_device *netdev,
434 bdaddr_t *peer_addr, u8 *peer_addr_type)
435{
436 struct in6_addr ipv6_daddr;
437 struct ipv6hdr *hdr;
438 struct lowpan_btle_dev *dev;
439 struct lowpan_peer *peer;
440 bdaddr_t addr, *any = BDADDR_ANY;
441 u8 *daddr = any->b;
442 int err, status = 0;
443
444 hdr = ipv6_hdr(skb);
445
446 dev = lowpan_btle_dev(netdev);
447
448 memcpy(&ipv6_daddr, &hdr->daddr, sizeof(ipv6_daddr));
449
450 if (ipv6_addr_is_multicast(&ipv6_daddr)) {
451 lowpan_cb(skb)->chan = NULL;
452 } else {
453 u8 addr_type;
454
455 /* Get destination BT device from skb.
456 * If there is no such peer then discard the packet.
457 */
458 convert_dest_bdaddr(&ipv6_daddr, &addr, &addr_type);
459
460 BT_DBG("dest addr %pMR type %d IP %pI6c", &addr,
461 addr_type, &ipv6_daddr);
462
463 peer = peer_lookup_ba(dev, &addr, addr_type);
464 if (!peer) {
465 /* The packet might be sent to 6lowpan interface
466 * because of routing (either via default route
467 * or user set route) so get peer according to
468 * the destination address.
469 */
470 peer = peer_lookup_dst(dev, &ipv6_daddr, skb);
471 if (!peer) {
472 BT_DBG("no such peer %pMR found", &addr);
473 return -ENOENT;
474 }
475 }
476
477 daddr = peer->eui64_addr;
478 *peer_addr = addr;
479 *peer_addr_type = addr_type;
480 lowpan_cb(skb)->chan = peer->chan;
481
482 status = 1;
483 }
484
485 lowpan_header_compress(skb, netdev, daddr, dev->netdev->dev_addr);
486
487 err = dev_hard_header(skb, netdev, ETH_P_IPV6, NULL, NULL, 0);
488 if (err < 0)
489 return err;
490
491 return status;
492}
493
494static int header_create(struct sk_buff *skb, struct net_device *netdev,
495 unsigned short type, const void *_daddr,
496 const void *_saddr, unsigned int len)
497{
498 if (type != ETH_P_IPV6)
499 return -EINVAL;
500
501 return 0;
502}
503
504/* Packet to BT LE device */
505static int send_pkt(struct l2cap_chan *chan, struct sk_buff *skb,
506 struct net_device *netdev)
507{
508 struct msghdr msg;
509 struct kvec iv;
510 int err;
511
512 /* Remember the skb so that we can send EAGAIN to the caller if
513 * we run out of credits.
514 */
515 chan->data = skb;
516
517 iv.iov_base = skb->data;
518 iv.iov_len = skb->len;
519
520 memset(&msg, 0, sizeof(msg));
521 iov_iter_kvec(&msg.msg_iter, WRITE | ITER_KVEC, &iv, 1, skb->len);
522
523 err = l2cap_chan_send(chan, &msg, skb->len);
524 if (err > 0) {
525 netdev->stats.tx_bytes += err;
526 netdev->stats.tx_packets++;
527 return 0;
528 }
529
530 if (!err)
531 err = lowpan_cb(skb)->status;
532
533 if (err < 0) {
534 if (err == -EAGAIN)
535 netdev->stats.tx_dropped++;
536 else
537 netdev->stats.tx_errors++;
538 }
539
540 return err;
541}
542
543static int send_mcast_pkt(struct sk_buff *skb, struct net_device *netdev)
544{
545 struct sk_buff *local_skb;
546 struct lowpan_btle_dev *entry;
547 int err = 0;
548
549 rcu_read_lock();
550
551 list_for_each_entry_rcu(entry, &bt_6lowpan_devices, list) {
552 struct lowpan_peer *pentry;
553 struct lowpan_btle_dev *dev;
554
555 if (entry->netdev != netdev)
556 continue;
557
558 dev = lowpan_btle_dev(entry->netdev);
559
560 list_for_each_entry_rcu(pentry, &dev->peers, list) {
561 int ret;
562
563 local_skb = skb_clone(skb, GFP_ATOMIC);
564
565 BT_DBG("xmit %s to %pMR type %d IP %pI6c chan %p",
566 netdev->name,
567 &pentry->chan->dst, pentry->chan->dst_type,
568 &pentry->peer_addr, pentry->chan);
569 ret = send_pkt(pentry->chan, local_skb, netdev);
570 if (ret < 0)
571 err = ret;
572
573 kfree_skb(local_skb);
574 }
575 }
576
577 rcu_read_unlock();
578
579 return err;
580}
581
582static netdev_tx_t bt_xmit(struct sk_buff *skb, struct net_device *netdev)
583{
584 int err = 0;
585 bdaddr_t addr;
586 u8 addr_type;
587
588 /* We must take a copy of the skb before we modify/replace the ipv6
589 * header as the header could be used elsewhere
590 */
591 skb = skb_unshare(skb, GFP_ATOMIC);
592 if (!skb)
593 return NET_XMIT_DROP;
594
595 /* Return values from setup_header()
596 * <0 - error, packet is dropped
597 * 0 - this is a multicast packet
598 * 1 - this is unicast packet
599 */
600 err = setup_header(skb, netdev, &addr, &addr_type);
601 if (err < 0) {
602 kfree_skb(skb);
603 return NET_XMIT_DROP;
604 }
605
606 if (err) {
607 if (lowpan_cb(skb)->chan) {
608 BT_DBG("xmit %s to %pMR type %d IP %pI6c chan %p",
609 netdev->name, &addr, addr_type,
610 &lowpan_cb(skb)->addr, lowpan_cb(skb)->chan);
611 err = send_pkt(lowpan_cb(skb)->chan, skb, netdev);
612 } else {
613 err = -ENOENT;
614 }
615 } else {
616 /* We need to send the packet to every device behind this
617 * interface.
618 */
619 err = send_mcast_pkt(skb, netdev);
620 }
621
622 dev_kfree_skb(skb);
623
624 if (err)
625 BT_DBG("ERROR: xmit failed (%d)", err);
626
627 return err < 0 ? NET_XMIT_DROP : err;
628}
629
630static int bt_dev_init(struct net_device *dev)
631{
632 netdev_lockdep_set_classes(dev);
633
634 return 0;
635}
636
637static const struct net_device_ops netdev_ops = {
638 .ndo_init = bt_dev_init,
639 .ndo_start_xmit = bt_xmit,
640};
641
642static struct header_ops header_ops = {
643 .create = header_create,
644};
645
646static void netdev_setup(struct net_device *dev)
647{
648 dev->hard_header_len = 0;
649 dev->needed_tailroom = 0;
650 dev->flags = IFF_RUNNING | IFF_POINTOPOINT |
651 IFF_MULTICAST;
652 dev->watchdog_timeo = 0;
653
654 dev->netdev_ops = &netdev_ops;
655 dev->header_ops = &header_ops;
656 dev->destructor = free_netdev;
657}
658
659static struct device_type bt_type = {
660 .name = "bluetooth",
661};
662
663static void set_addr(u8 *eui, u8 *addr, u8 addr_type)
664{
665 /* addr is the BT address in little-endian format */
666 eui[0] = addr[5];
667 eui[1] = addr[4];
668 eui[2] = addr[3];
669 eui[3] = 0xFF;
670 eui[4] = 0xFE;
671 eui[5] = addr[2];
672 eui[6] = addr[1];
673 eui[7] = addr[0];
674
675 /* Universal/local bit set, BT 6lowpan draft ch. 3.2.1 */
676 if (addr_type == BDADDR_LE_PUBLIC)
677 eui[0] &= ~0x02;
678 else
679 eui[0] |= 0x02;
680
681 BT_DBG("type %d addr %*phC", addr_type, 8, eui);
682}
683
684static void set_dev_addr(struct net_device *netdev, bdaddr_t *addr,
685 u8 addr_type)
686{
687 netdev->addr_assign_type = NET_ADDR_PERM;
688 set_addr(netdev->dev_addr, addr->b, addr_type);
689}
690
691static void ifup(struct net_device *netdev)
692{
693 int err;
694
695 rtnl_lock();
696 err = dev_open(netdev);
697 if (err < 0)
698 BT_INFO("iface %s cannot be opened (%d)", netdev->name, err);
699 rtnl_unlock();
700}
701
702static void ifdown(struct net_device *netdev)
703{
704 int err;
705
706 rtnl_lock();
707 err = dev_close(netdev);
708 if (err < 0)
709 BT_INFO("iface %s cannot be closed (%d)", netdev->name, err);
710 rtnl_unlock();
711}
712
713static void do_notify_peers(struct work_struct *work)
714{
715 struct lowpan_btle_dev *dev = container_of(work, struct lowpan_btle_dev,
716 notify_peers.work);
717
718 netdev_notify_peers(dev->netdev); /* send neighbour adv at startup */
719}
720
721static bool is_bt_6lowpan(struct hci_conn *hcon)
722{
723 if (hcon->type != LE_LINK)
724 return false;
725
726 if (!enable_6lowpan)
727 return false;
728
729 return true;
730}
731
732static struct l2cap_chan *chan_create(void)
733{
734 struct l2cap_chan *chan;
735
736 chan = l2cap_chan_create();
737 if (!chan)
738 return NULL;
739
740 l2cap_chan_set_defaults(chan);
741
742 chan->chan_type = L2CAP_CHAN_CONN_ORIENTED;
743 chan->mode = L2CAP_MODE_LE_FLOWCTL;
744 chan->imtu = 1280;
745
746 return chan;
747}
748
749static void set_ip_addr_bits(u8 addr_type, u8 *addr)
750{
751 if (addr_type == BDADDR_LE_PUBLIC)
752 *addr |= 0x02;
753 else
754 *addr &= ~0x02;
755}
756
757static struct l2cap_chan *add_peer_chan(struct l2cap_chan *chan,
758 struct lowpan_btle_dev *dev)
759{
760 struct lowpan_peer *peer;
761
762 peer = kzalloc(sizeof(*peer), GFP_ATOMIC);
763 if (!peer)
764 return NULL;
765
766 peer->chan = chan;
767 memset(&peer->peer_addr, 0, sizeof(struct in6_addr));
768
769 /* RFC 2464 ch. 5 */
770 peer->peer_addr.s6_addr[0] = 0xFE;
771 peer->peer_addr.s6_addr[1] = 0x80;
772 set_addr((u8 *)&peer->peer_addr.s6_addr + 8, chan->dst.b,
773 chan->dst_type);
774
775 memcpy(&peer->eui64_addr, (u8 *)&peer->peer_addr.s6_addr + 8,
776 EUI64_ADDR_LEN);
777
778 /* IPv6 address needs to have the U/L bit set properly so toggle
779 * it back here.
780 */
781 set_ip_addr_bits(chan->dst_type, (u8 *)&peer->peer_addr.s6_addr + 8);
782
783 spin_lock(&devices_lock);
784 INIT_LIST_HEAD(&peer->list);
785 peer_add(dev, peer);
786 spin_unlock(&devices_lock);
787
788 /* Notifying peers about us needs to be done without locks held */
789 INIT_DELAYED_WORK(&dev->notify_peers, do_notify_peers);
790 schedule_delayed_work(&dev->notify_peers, msecs_to_jiffies(100));
791
792 return peer->chan;
793}
794
795static int setup_netdev(struct l2cap_chan *chan, struct lowpan_btle_dev **dev)
796{
797 struct net_device *netdev;
798 int err = 0;
799
800 netdev = alloc_netdev(LOWPAN_PRIV_SIZE(sizeof(struct lowpan_btle_dev)),
801 IFACE_NAME_TEMPLATE, NET_NAME_UNKNOWN,
802 netdev_setup);
803 if (!netdev)
804 return -ENOMEM;
805
806 set_dev_addr(netdev, &chan->src, chan->src_type);
807
808 netdev->netdev_ops = &netdev_ops;
809 SET_NETDEV_DEV(netdev, &chan->conn->hcon->hdev->dev);
810 SET_NETDEV_DEVTYPE(netdev, &bt_type);
811
812 *dev = lowpan_btle_dev(netdev);
813 (*dev)->netdev = netdev;
814 (*dev)->hdev = chan->conn->hcon->hdev;
815 INIT_LIST_HEAD(&(*dev)->peers);
816
817 spin_lock(&devices_lock);
818 INIT_LIST_HEAD(&(*dev)->list);
819 list_add_rcu(&(*dev)->list, &bt_6lowpan_devices);
820 spin_unlock(&devices_lock);
821
822 err = lowpan_register_netdev(netdev, LOWPAN_LLTYPE_BTLE);
823 if (err < 0) {
824 BT_INFO("register_netdev failed %d", err);
825 spin_lock(&devices_lock);
826 list_del_rcu(&(*dev)->list);
827 spin_unlock(&devices_lock);
828 free_netdev(netdev);
829 goto out;
830 }
831
832 BT_DBG("ifindex %d peer bdaddr %pMR type %d my addr %pMR type %d",
833 netdev->ifindex, &chan->dst, chan->dst_type,
834 &chan->src, chan->src_type);
835 set_bit(__LINK_STATE_PRESENT, &netdev->state);
836
837 return 0;
838
839out:
840 return err;
841}
842
843static inline void chan_ready_cb(struct l2cap_chan *chan)
844{
845 struct lowpan_btle_dev *dev;
846
847 dev = lookup_dev(chan->conn);
848
849 BT_DBG("chan %p conn %p dev %p", chan, chan->conn, dev);
850
851 if (!dev) {
852 if (setup_netdev(chan, &dev) < 0) {
853 l2cap_chan_del(chan, -ENOENT);
854 return;
855 }
856 }
857
858 if (!try_module_get(THIS_MODULE))
859 return;
860
861 add_peer_chan(chan, dev);
862 ifup(dev->netdev);
863}
864
865static inline struct l2cap_chan *chan_new_conn_cb(struct l2cap_chan *pchan)
866{
867 struct l2cap_chan *chan;
868
869 chan = chan_create();
870 if (!chan)
871 return NULL;
872
873 chan->ops = pchan->ops;
874
875 BT_DBG("chan %p pchan %p", chan, pchan);
876
877 return chan;
878}
879
880static void delete_netdev(struct work_struct *work)
881{
882 struct lowpan_btle_dev *entry = container_of(work,
883 struct lowpan_btle_dev,
884 delete_netdev);
885
886 lowpan_unregister_netdev(entry->netdev);
887
888 /* The entry pointer is deleted by the netdev destructor. */
889}
890
891static void chan_close_cb(struct l2cap_chan *chan)
892{
893 struct lowpan_btle_dev *entry;
894 struct lowpan_btle_dev *dev = NULL;
895 struct lowpan_peer *peer;
896 int err = -ENOENT;
897 bool last = false, remove = true;
898
899 BT_DBG("chan %p conn %p", chan, chan->conn);
900
901 if (chan->conn && chan->conn->hcon) {
902 if (!is_bt_6lowpan(chan->conn->hcon))
903 return;
904
905 /* If conn is set, then the netdev is also there and we should
906 * not remove it.
907 */
908 remove = false;
909 }
910
911 spin_lock(&devices_lock);
912
913 list_for_each_entry_rcu(entry, &bt_6lowpan_devices, list) {
914 dev = lowpan_btle_dev(entry->netdev);
915 peer = __peer_lookup_chan(dev, chan);
916 if (peer) {
917 last = peer_del(dev, peer);
918 err = 0;
919
920 BT_DBG("dev %p removing %speer %p", dev,
921 last ? "last " : "1 ", peer);
922 BT_DBG("chan %p orig refcnt %d", chan,
923 atomic_read(&chan->kref.refcount));
924
925 l2cap_chan_put(chan);
926 break;
927 }
928 }
929
930 if (!err && last && dev && !atomic_read(&dev->peer_count)) {
931 spin_unlock(&devices_lock);
932
933 cancel_delayed_work_sync(&dev->notify_peers);
934
935 ifdown(dev->netdev);
936
937 if (remove) {
938 INIT_WORK(&entry->delete_netdev, delete_netdev);
939 schedule_work(&entry->delete_netdev);
940 }
941 } else {
942 spin_unlock(&devices_lock);
943 }
944
945 return;
946}
947
948static void chan_state_change_cb(struct l2cap_chan *chan, int state, int err)
949{
950 BT_DBG("chan %p conn %p state %s err %d", chan, chan->conn,
951 state_to_string(state), err);
952}
953
954static struct sk_buff *chan_alloc_skb_cb(struct l2cap_chan *chan,
955 unsigned long hdr_len,
956 unsigned long len, int nb)
957{
958 /* Note that we must allocate using GFP_ATOMIC here as
959 * this function is called originally from netdev hard xmit
960 * function in atomic context.
961 */
962 return bt_skb_alloc(hdr_len + len, GFP_ATOMIC);
963}
964
965static void chan_suspend_cb(struct l2cap_chan *chan)
966{
967 struct sk_buff *skb = chan->data;
968
969 BT_DBG("chan %p conn %p skb %p", chan, chan->conn, skb);
970
971 if (!skb)
972 return;
973
974 lowpan_cb(skb)->status = -EAGAIN;
975}
976
977static void chan_resume_cb(struct l2cap_chan *chan)
978{
979 struct sk_buff *skb = chan->data;
980
981 BT_DBG("chan %p conn %p skb %p", chan, chan->conn, skb);
982
983 if (!skb)
984 return;
985
986 lowpan_cb(skb)->status = 0;
987}
988
989static long chan_get_sndtimeo_cb(struct l2cap_chan *chan)
990{
991 return L2CAP_CONN_TIMEOUT;
992}
993
994static const struct l2cap_ops bt_6lowpan_chan_ops = {
995 .name = "L2CAP 6LoWPAN channel",
996 .new_connection = chan_new_conn_cb,
997 .recv = chan_recv_cb,
998 .close = chan_close_cb,
999 .state_change = chan_state_change_cb,
1000 .ready = chan_ready_cb,
1001 .resume = chan_resume_cb,
1002 .suspend = chan_suspend_cb,
1003 .get_sndtimeo = chan_get_sndtimeo_cb,
1004 .alloc_skb = chan_alloc_skb_cb,
1005
1006 .teardown = l2cap_chan_no_teardown,
1007 .defer = l2cap_chan_no_defer,
1008 .set_shutdown = l2cap_chan_no_set_shutdown,
1009};
1010
1011static inline __u8 bdaddr_type(__u8 type)
1012{
1013 if (type == ADDR_LE_DEV_PUBLIC)
1014 return BDADDR_LE_PUBLIC;
1015 else
1016 return BDADDR_LE_RANDOM;
1017}
1018
1019static int bt_6lowpan_connect(bdaddr_t *addr, u8 dst_type)
1020{
1021 struct l2cap_chan *chan;
1022 int err;
1023
1024 chan = chan_create();
1025 if (!chan)
1026 return -EINVAL;
1027
1028 chan->ops = &bt_6lowpan_chan_ops;
1029
1030 err = l2cap_chan_connect(chan, cpu_to_le16(L2CAP_PSM_IPSP), 0,
1031 addr, dst_type);
1032
1033 BT_DBG("chan %p err %d", chan, err);
1034 if (err < 0)
1035 l2cap_chan_put(chan);
1036
1037 return err;
1038}
1039
1040static int bt_6lowpan_disconnect(struct l2cap_conn *conn, u8 dst_type)
1041{
1042 struct lowpan_peer *peer;
1043
1044 BT_DBG("conn %p dst type %d", conn, dst_type);
1045
1046 peer = lookup_peer(conn);
1047 if (!peer)
1048 return -ENOENT;
1049
1050 BT_DBG("peer %p chan %p", peer, peer->chan);
1051
1052 l2cap_chan_close(peer->chan, ENOENT);
1053
1054 return 0;
1055}
1056
1057static struct l2cap_chan *bt_6lowpan_listen(void)
1058{
1059 bdaddr_t *addr = BDADDR_ANY;
1060 struct l2cap_chan *chan;
1061 int err;
1062
1063 if (!enable_6lowpan)
1064 return NULL;
1065
1066 chan = chan_create();
1067 if (!chan)
1068 return NULL;
1069
1070 chan->ops = &bt_6lowpan_chan_ops;
1071 chan->state = BT_LISTEN;
1072 chan->src_type = BDADDR_LE_PUBLIC;
1073
1074 atomic_set(&chan->nesting, L2CAP_NESTING_PARENT);
1075
1076 BT_DBG("chan %p src type %d", chan, chan->src_type);
1077
1078 err = l2cap_add_psm(chan, addr, cpu_to_le16(L2CAP_PSM_IPSP));
1079 if (err) {
1080 l2cap_chan_put(chan);
1081 BT_ERR("psm cannot be added err %d", err);
1082 return NULL;
1083 }
1084
1085 return chan;
1086}
1087
1088static int get_l2cap_conn(char *buf, bdaddr_t *addr, u8 *addr_type,
1089 struct l2cap_conn **conn)
1090{
1091 struct hci_conn *hcon;
1092 struct hci_dev *hdev;
1093 int n;
1094
1095 n = sscanf(buf, "%hhx:%hhx:%hhx:%hhx:%hhx:%hhx %hhu",
1096 &addr->b[5], &addr->b[4], &addr->b[3],
1097 &addr->b[2], &addr->b[1], &addr->b[0],
1098 addr_type);
1099
1100 if (n < 7)
1101 return -EINVAL;
1102
1103 /* The LE_PUBLIC address type is ignored because of BDADDR_ANY */
1104 hdev = hci_get_route(addr, BDADDR_ANY, BDADDR_LE_PUBLIC);
1105 if (!hdev)
1106 return -ENOENT;
1107
1108 hci_dev_lock(hdev);
1109 hcon = hci_conn_hash_lookup_le(hdev, addr, *addr_type);
1110 hci_dev_unlock(hdev);
1111
1112 if (!hcon)
1113 return -ENOENT;
1114
1115 *conn = (struct l2cap_conn *)hcon->l2cap_data;
1116
1117 BT_DBG("conn %p dst %pMR type %d", *conn, &hcon->dst, hcon->dst_type);
1118
1119 return 0;
1120}
1121
1122static void disconnect_all_peers(void)
1123{
1124 struct lowpan_btle_dev *entry;
1125 struct lowpan_peer *peer, *tmp_peer, *new_peer;
1126 struct list_head peers;
1127
1128 INIT_LIST_HEAD(&peers);
1129
1130 /* We make a separate list of peers as the close_cb() will
1131 * modify the device peers list so it is better not to mess
1132 * with the same list at the same time.
1133 */
1134
1135 rcu_read_lock();
1136
1137 list_for_each_entry_rcu(entry, &bt_6lowpan_devices, list) {
1138 list_for_each_entry_rcu(peer, &entry->peers, list) {
1139 new_peer = kmalloc(sizeof(*new_peer), GFP_ATOMIC);
1140 if (!new_peer)
1141 break;
1142
1143 new_peer->chan = peer->chan;
1144 INIT_LIST_HEAD(&new_peer->list);
1145
1146 list_add(&new_peer->list, &peers);
1147 }
1148 }
1149
1150 rcu_read_unlock();
1151
1152 spin_lock(&devices_lock);
1153 list_for_each_entry_safe(peer, tmp_peer, &peers, list) {
1154 l2cap_chan_close(peer->chan, ENOENT);
1155
1156 list_del_rcu(&peer->list);
1157 kfree_rcu(peer, rcu);
1158 }
1159 spin_unlock(&devices_lock);
1160}
1161
1162struct set_enable {
1163 struct work_struct work;
1164 bool flag;
1165};
1166
1167static void do_enable_set(struct work_struct *work)
1168{
1169 struct set_enable *set_enable = container_of(work,
1170 struct set_enable, work);
1171
1172 if (!set_enable->flag || enable_6lowpan != set_enable->flag)
1173 /* Disconnect existing connections if 6lowpan is
1174 * disabled
1175 */
1176 disconnect_all_peers();
1177
1178 enable_6lowpan = set_enable->flag;
1179
1180 if (listen_chan) {
1181 l2cap_chan_close(listen_chan, 0);
1182 l2cap_chan_put(listen_chan);
1183 }
1184
1185 listen_chan = bt_6lowpan_listen();
1186
1187 kfree(set_enable);
1188}
1189
1190static int lowpan_enable_set(void *data, u64 val)
1191{
1192 struct set_enable *set_enable;
1193
1194 set_enable = kzalloc(sizeof(*set_enable), GFP_KERNEL);
1195 if (!set_enable)
1196 return -ENOMEM;
1197
1198 set_enable->flag = !!val;
1199 INIT_WORK(&set_enable->work, do_enable_set);
1200
1201 schedule_work(&set_enable->work);
1202
1203 return 0;
1204}
1205
1206static int lowpan_enable_get(void *data, u64 *val)
1207{
1208 *val = enable_6lowpan;
1209 return 0;
1210}
1211
1212DEFINE_SIMPLE_ATTRIBUTE(lowpan_enable_fops, lowpan_enable_get,
1213 lowpan_enable_set, "%llu\n");
1214
1215static ssize_t lowpan_control_write(struct file *fp,
1216 const char __user *user_buffer,
1217 size_t count,
1218 loff_t *position)
1219{
1220 char buf[32];
1221 size_t buf_size = min(count, sizeof(buf) - 1);
1222 int ret;
1223 bdaddr_t addr;
1224 u8 addr_type;
1225 struct l2cap_conn *conn = NULL;
1226
1227 if (copy_from_user(buf, user_buffer, buf_size))
1228 return -EFAULT;
1229
1230 buf[buf_size] = '\0';
1231
1232 if (memcmp(buf, "connect ", 8) == 0) {
1233 ret = get_l2cap_conn(&buf[8], &addr, &addr_type, &conn);
1234 if (ret == -EINVAL)
1235 return ret;
1236
1237 if (listen_chan) {
1238 l2cap_chan_close(listen_chan, 0);
1239 l2cap_chan_put(listen_chan);
1240 listen_chan = NULL;
1241 }
1242
1243 if (conn) {
1244 struct lowpan_peer *peer;
1245
1246 if (!is_bt_6lowpan(conn->hcon))
1247 return -EINVAL;
1248
1249 peer = lookup_peer(conn);
1250 if (peer) {
1251 BT_DBG("6LoWPAN connection already exists");
1252 return -EALREADY;
1253 }
1254
1255 BT_DBG("conn %p dst %pMR type %d user %d", conn,
1256 &conn->hcon->dst, conn->hcon->dst_type,
1257 addr_type);
1258 }
1259
1260 ret = bt_6lowpan_connect(&addr, addr_type);
1261 if (ret < 0)
1262 return ret;
1263
1264 return count;
1265 }
1266
1267 if (memcmp(buf, "disconnect ", 11) == 0) {
1268 ret = get_l2cap_conn(&buf[11], &addr, &addr_type, &conn);
1269 if (ret < 0)
1270 return ret;
1271
1272 ret = bt_6lowpan_disconnect(conn, addr_type);
1273 if (ret < 0)
1274 return ret;
1275
1276 return count;
1277 }
1278
1279 return count;
1280}
1281
1282static int lowpan_control_show(struct seq_file *f, void *ptr)
1283{
1284 struct lowpan_btle_dev *entry;
1285 struct lowpan_peer *peer;
1286
1287 spin_lock(&devices_lock);
1288
1289 list_for_each_entry(entry, &bt_6lowpan_devices, list) {
1290 list_for_each_entry(peer, &entry->peers, list)
1291 seq_printf(f, "%pMR (type %u)\n",
1292 &peer->chan->dst, peer->chan->dst_type);
1293 }
1294
1295 spin_unlock(&devices_lock);
1296
1297 return 0;
1298}
1299
1300static int lowpan_control_open(struct inode *inode, struct file *file)
1301{
1302 return single_open(file, lowpan_control_show, inode->i_private);
1303}
1304
1305static const struct file_operations lowpan_control_fops = {
1306 .open = lowpan_control_open,
1307 .read = seq_read,
1308 .write = lowpan_control_write,
1309 .llseek = seq_lseek,
1310 .release = single_release,
1311};
1312
1313static void disconnect_devices(void)
1314{
1315 struct lowpan_btle_dev *entry, *tmp, *new_dev;
1316 struct list_head devices;
1317
1318 INIT_LIST_HEAD(&devices);
1319
1320 /* We make a separate list of devices because the unregister_netdev()
1321 * will call device_event() which will also want to modify the same
1322 * devices list.
1323 */
1324
1325 rcu_read_lock();
1326
1327 list_for_each_entry_rcu(entry, &bt_6lowpan_devices, list) {
1328 new_dev = kmalloc(sizeof(*new_dev), GFP_ATOMIC);
1329 if (!new_dev)
1330 break;
1331
1332 new_dev->netdev = entry->netdev;
1333 INIT_LIST_HEAD(&new_dev->list);
1334
1335 list_add_rcu(&new_dev->list, &devices);
1336 }
1337
1338 rcu_read_unlock();
1339
1340 list_for_each_entry_safe(entry, tmp, &devices, list) {
1341 ifdown(entry->netdev);
1342 BT_DBG("Unregistering netdev %s %p",
1343 entry->netdev->name, entry->netdev);
1344 lowpan_unregister_netdev(entry->netdev);
1345 kfree(entry);
1346 }
1347}
1348
1349static int device_event(struct notifier_block *unused,
1350 unsigned long event, void *ptr)
1351{
1352 struct net_device *netdev = netdev_notifier_info_to_dev(ptr);
1353 struct lowpan_btle_dev *entry;
1354
1355 if (netdev->type != ARPHRD_6LOWPAN)
1356 return NOTIFY_DONE;
1357
1358 switch (event) {
1359 case NETDEV_UNREGISTER:
1360 spin_lock(&devices_lock);
1361 list_for_each_entry(entry, &bt_6lowpan_devices, list) {
1362 if (entry->netdev == netdev) {
1363 BT_DBG("Unregistered netdev %s %p",
1364 netdev->name, netdev);
1365 list_del(&entry->list);
1366 break;
1367 }
1368 }
1369 spin_unlock(&devices_lock);
1370 break;
1371 }
1372
1373 return NOTIFY_DONE;
1374}
1375
1376static struct notifier_block bt_6lowpan_dev_notifier = {
1377 .notifier_call = device_event,
1378};
1379
1380static int __init bt_6lowpan_init(void)
1381{
1382 lowpan_enable_debugfs = debugfs_create_file("6lowpan_enable", 0644,
1383 bt_debugfs, NULL,
1384 &lowpan_enable_fops);
1385 lowpan_control_debugfs = debugfs_create_file("6lowpan_control", 0644,
1386 bt_debugfs, NULL,
1387 &lowpan_control_fops);
1388
1389 return register_netdevice_notifier(&bt_6lowpan_dev_notifier);
1390}
1391
1392static void __exit bt_6lowpan_exit(void)
1393{
1394 debugfs_remove(lowpan_enable_debugfs);
1395 debugfs_remove(lowpan_control_debugfs);
1396
1397 if (listen_chan) {
1398 l2cap_chan_close(listen_chan, 0);
1399 l2cap_chan_put(listen_chan);
1400 }
1401
1402 disconnect_devices();
1403
1404 unregister_netdevice_notifier(&bt_6lowpan_dev_notifier);
1405}
1406
1407module_init(bt_6lowpan_init);
1408module_exit(bt_6lowpan_exit);
1409
1410MODULE_AUTHOR("Jukka Rissanen <jukka.rissanen@linux.intel.com>");
1411MODULE_DESCRIPTION("Bluetooth 6LoWPAN");
1412MODULE_VERSION(VERSION);
1413MODULE_LICENSE("GPL");