net/bluetooth/6lowpan.c

   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/af_ieee802154.h> /* to get the address type */
  25
  26 #include <net/bluetooth/bluetooth.h>
  27 #include <net/bluetooth/hci_core.h>
  28 #include <net/bluetooth/l2cap.h>
  29
  30 #include <net/6lowpan.h> /* for the compression support */
  31
  32 #define VERSION "0.1"
  33
  34 static struct dentry *lowpan_enable_debugfs;
  35 static struct dentry *lowpan_control_debugfs;
  36
  37 #define IFACE_NAME_TEMPLATE "bt%d"
  38 #define EUI64_ADDR_LEN 8
  39
  40 struct skb_cb {
  41         struct in6_addr addr;
  42         struct in6_addr gw;
  43         struct l2cap_chan *chan;
  44         int status;
  45 };
  46 #define lowpan_cb(skb) ((struct skb_cb *)((skb)->cb))
  47
  48 /* The devices list contains those devices that we are acting
  49  * as a proxy. The BT 6LoWPAN device is a virtual device that
  50  * connects to the Bluetooth LE device. The real connection to
  51  * BT device is done via l2cap layer. There exists one
  52  * virtual device / one BT 6LoWPAN network (=hciX device).
  53  * The list contains struct lowpan_dev elements.
  54  */
  55 static LIST_HEAD(bt_6lowpan_devices);
  56 static DEFINE_SPINLOCK(devices_lock);
  57
  58 static bool enable_6lowpan;
  59
  60 /* We are listening incoming connections via this channel
  61  */
  62 static struct l2cap_chan *listen_chan;
  63
  64 struct lowpan_peer {
  65         struct list_head list;
  66         struct rcu_head rcu;
  67         struct l2cap_chan *chan;
  68
  69         /* peer addresses in various formats */
  70         unsigned char eui64_addr[EUI64_ADDR_LEN];
  71         struct in6_addr peer_addr;
  72 };
  73
  74 struct lowpan_dev {
  75         struct list_head list;
  76
  77         struct hci_dev *hdev;
  78         struct net_device *netdev;
  79         struct list_head peers;
  80         atomic_t peer_count; /* number of items in peers list */
  81
  82         struct work_struct delete_netdev;
  83         struct delayed_work notify_peers;
  84 };
  85
  86 static inline struct lowpan_dev *lowpan_dev(const struct net_device *netdev)
  87 {
  88         return (struct lowpan_dev *)lowpan_priv(netdev)->priv;
  89 }
  90
  91 static inline void peer_add(struct lowpan_dev *dev, struct lowpan_peer *peer)
  92 {
  93         list_add_rcu(&peer->list, &dev->peers);
  94         atomic_inc(&dev->peer_count);
  95 }
  96
  97 static inline bool peer_del(struct lowpan_dev *dev, 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
 112 static inline struct lowpan_peer *peer_lookup_ba(struct lowpan_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
 140 static inline struct lowpan_peer *__peer_lookup_chan(struct lowpan_dev *dev,
 141                                                      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
 153 static inline struct lowpan_peer *__peer_lookup_conn(struct lowpan_dev *dev,
 154                                                      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
 166 static inline struct lowpan_peer *peer_lookup_dst(struct lowpan_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
 224 static struct lowpan_peer *lookup_peer(struct l2cap_conn *conn)
 225 {
 226         struct lowpan_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
 242 static struct lowpan_dev *lookup_dev(struct l2cap_conn *conn)
 243 {
 244         struct lowpan_dev *entry;
 245         struct lowpan_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
 261 static 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(skb_cp);
 270 }
 271
 272 static int iphc_decompress(struct sk_buff *skb, struct net_device *netdev,
 273                            struct l2cap_chan *chan)
 274 {
 275         const u8 *saddr, *daddr;
 276         u8 iphc0, iphc1;
 277         struct lowpan_dev *dev;
 278         struct lowpan_peer *peer;
 279
 280         dev = lowpan_dev(netdev);
 281
 282         rcu_read_lock();
 283         peer = __peer_lookup_chan(dev, chan);
 284         rcu_read_unlock();
 285         if (!peer)
 286                 return -EINVAL;
 287
 288         saddr = peer->eui64_addr;
 289         daddr = dev->netdev->dev_addr;
 290
 291         /* at least two bytes will be used for the encoding */
 292         if (skb->len < 2)
 293                 return -EINVAL;
 294
 295         if (lowpan_fetch_skb_u8(skb, &iphc0))
 296                 return -EINVAL;
 297
 298         if (lowpan_fetch_skb_u8(skb, &iphc1))
 299                 return -EINVAL;
 300
 301         return lowpan_header_decompress(skb, netdev,
 302                                         saddr, IEEE802154_ADDR_LONG,
 303                                         EUI64_ADDR_LEN, daddr,
 304                                         IEEE802154_ADDR_LONG, EUI64_ADDR_LEN,
 305                                         iphc0, iphc1);
 306
 307 }
 308
 309 static int recv_pkt(struct sk_buff *skb, struct net_device *dev,
 310                     struct l2cap_chan *chan)
 311 {
 312         struct sk_buff *local_skb;
 313         int ret;
 314
 315         if (!netif_running(dev))
 316                 goto drop;
 317
 318         if (dev->type != ARPHRD_6LOWPAN)
 319                 goto drop;
 320
 321         skb = skb_share_check(skb, GFP_ATOMIC);
 322         if (!skb)
 323                 goto drop;
 324
 325         /* check that it's our buffer */
 326         if (skb->data[0] == LOWPAN_DISPATCH_IPV6) {
 327                 /* Copy the packet so that the IPv6 header is
 328                  * properly aligned.
 329                  */
 330                 local_skb = skb_copy_expand(skb, NET_SKB_PAD - 1,
 331                                             skb_tailroom(skb), GFP_ATOMIC);
 332                 if (!local_skb)
 333                         goto drop;
 334
 335                 local_skb->protocol = htons(ETH_P_IPV6);
 336                 local_skb->pkt_type = PACKET_HOST;
 337
 338                 skb_reset_network_header(local_skb);
 339                 skb_set_transport_header(local_skb, sizeof(struct ipv6hdr));
 340
 341                 if (give_skb_to_upper(local_skb, dev) != NET_RX_SUCCESS) {
 342                         kfree_skb(local_skb);
 343                         goto drop;
 344                 }
 345
 346                 dev->stats.rx_bytes += skb->len;
 347                 dev->stats.rx_packets++;
 348
 349                 consume_skb(local_skb);
 350                 consume_skb(skb);
 351         } else {
 352                 switch (skb->data[0] & 0xe0) {
 353                 case LOWPAN_DISPATCH_IPHC:      /* ipv6 datagram */
 354                         local_skb = skb_clone(skb, GFP_ATOMIC);
 355                         if (!local_skb)
 356                                 goto drop;
 357
 358                         ret = iphc_decompress(local_skb, dev, chan);
 359                         if (ret < 0) {
 360                                 kfree_skb(local_skb);
 361                                 goto drop;
 362                         }
 363
 364                         local_skb->protocol = htons(ETH_P_IPV6);
 365                         local_skb->pkt_type = PACKET_HOST;
 366                         local_skb->dev = dev;
 367
 368                         if (give_skb_to_upper(local_skb, dev)
 369                                         != NET_RX_SUCCESS) {
 370                                 kfree_skb(local_skb);
 371                                 goto drop;
 372                         }
 373
 374                         dev->stats.rx_bytes += skb->len;
 375                         dev->stats.rx_packets++;
 376
 377                         consume_skb(local_skb);
 378                         consume_skb(skb);
 379                         break;
 380                 default:
 381                         break;
 382                 }
 383         }
 384
 385         return NET_RX_SUCCESS;
 386
 387 drop:
 388         dev->stats.rx_dropped++;
 389         return NET_RX_DROP;
 390 }
 391
 392 /* Packet from BT LE device */
 393 static int chan_recv_cb(struct l2cap_chan *chan, struct sk_buff *skb)
 394 {
 395         struct lowpan_dev *dev;
 396         struct lowpan_peer *peer;
 397         int err;
 398
 399         peer = lookup_peer(chan->conn);
 400         if (!peer)
 401                 return -ENOENT;
 402
 403         dev = lookup_dev(chan->conn);
 404         if (!dev || !dev->netdev)
 405                 return -ENOENT;
 406
 407         err = recv_pkt(skb, dev->netdev, chan);
 408         if (err) {
 409                 BT_DBG("recv pkt %d", err);
 410                 err = -EAGAIN;
 411         }
 412
 413         return err;
 414 }
 415
 416 static u8 get_addr_type_from_eui64(u8 byte)
 417 {
 418         /* Is universal(0) or local(1) bit */
 419         return ((byte & 0x02) ? BDADDR_LE_RANDOM : BDADDR_LE_PUBLIC);
 420 }
 421
 422 static void copy_to_bdaddr(struct in6_addr *ip6_daddr, bdaddr_t *addr)
 423 {
 424         u8 *eui64 = ip6_daddr->s6_addr + 8;
 425
 426         addr->b[0] = eui64[7];
 427         addr->b[1] = eui64[6];
 428         addr->b[2] = eui64[5];
 429         addr->b[3] = eui64[2];
 430         addr->b[4] = eui64[1];
 431         addr->b[5] = eui64[0];
 432 }
 433
 434 static void convert_dest_bdaddr(struct in6_addr *ip6_daddr,
 435                                 bdaddr_t *addr, u8 *addr_type)
 436 {
 437         copy_to_bdaddr(ip6_daddr, addr);
 438
 439         /* We need to toggle the U/L bit that we got from IPv6 address
 440          * so that we get the proper address and type of the BD address.
 441          */
 442         addr->b[5] ^= 0x02;
 443
 444         *addr_type = get_addr_type_from_eui64(addr->b[5]);
 445 }
 446
 447 static int setup_header(struct sk_buff *skb, struct net_device *netdev,
 448                         bdaddr_t *peer_addr, u8 *peer_addr_type)
 449 {
 450         struct in6_addr ipv6_daddr;
 451         struct lowpan_dev *dev;
 452         struct lowpan_peer *peer;
 453         bdaddr_t addr, *any = BDADDR_ANY;
 454         u8 *daddr = any->b;
 455         int err, status = 0;
 456
 457         dev = lowpan_dev(netdev);
 458
 459         memcpy(&ipv6_daddr, &lowpan_cb(skb)->addr, sizeof(ipv6_daddr));
 460
 461         if (ipv6_addr_is_multicast(&ipv6_daddr)) {
 462                 lowpan_cb(skb)->chan = NULL;
 463         } else {
 464                 u8 addr_type;
 465
 466                 /* Get destination BT device from skb.
 467                  * If there is no such peer then discard the packet.
 468                  */
 469                 convert_dest_bdaddr(&ipv6_daddr, &addr, &addr_type);
 470
 471                 BT_DBG("dest addr %pMR type %d IP %pI6c", &addr,
 472                        addr_type, &ipv6_daddr);
 473
 474                 peer = peer_lookup_ba(dev, &addr, addr_type);
 475                 if (!peer) {
 476                         /* The packet might be sent to 6lowpan interface
 477                          * because of routing (either via default route
 478                          * or user set route) so get peer according to
 479                          * the destination address.
 480                          */
 481                         peer = peer_lookup_dst(dev, &ipv6_daddr, skb);
 482                         if (!peer) {
 483                                 BT_DBG("no such peer %pMR found", &addr);
 484                                 return -ENOENT;
 485                         }
 486                 }
 487
 488                 daddr = peer->eui64_addr;
 489                 *peer_addr = addr;
 490                 *peer_addr_type = addr_type;
 491                 lowpan_cb(skb)->chan = peer->chan;
 492
 493                 status = 1;
 494         }
 495
 496         lowpan_header_compress(skb, netdev, ETH_P_IPV6, daddr,
 497                                dev->netdev->dev_addr, skb->len);
 498
 499         err = dev_hard_header(skb, netdev, ETH_P_IPV6, NULL, NULL, 0);
 500         if (err < 0)
 501                 return err;
 502
 503         return status;
 504 }
 505
 506 static int header_create(struct sk_buff *skb, struct net_device *netdev,
 507                          unsigned short type, const void *_daddr,
 508                          const void *_saddr, unsigned int len)
 509 {
 510         struct ipv6hdr *hdr;
 511
 512         if (type != ETH_P_IPV6)
 513                 return -EINVAL;
 514
 515         hdr = ipv6_hdr(skb);
 516
 517         memcpy(&lowpan_cb(skb)->addr, &hdr->daddr, sizeof(struct in6_addr));
 518
 519         return 0;
 520 }
 521
 522 /* Packet to BT LE device */
 523 static int send_pkt(struct l2cap_chan *chan, struct sk_buff *skb,
 524                     struct net_device *netdev)
 525 {
 526         struct msghdr msg;
 527         struct kvec iv;
 528         int err;
 529
 530         /* Remember the skb so that we can send EAGAIN to the caller if
 531          * we run out of credits.
 532          */
 533         chan->data = skb;
 534
 535         iv.iov_base = skb->data;
 536         iv.iov_len = skb->len;
 537
 538         memset(&msg, 0, sizeof(msg));
 539         iov_iter_kvec(&msg.msg_iter, WRITE | ITER_KVEC, &iv, 1, skb->len);
 540
 541         err = l2cap_chan_send(chan, &msg, skb->len);
 542         if (err > 0) {
 543                 netdev->stats.tx_bytes += err;
 544                 netdev->stats.tx_packets++;
 545                 return 0;
 546         }
 547
 548         if (!err)
 549                 err = lowpan_cb(skb)->status;
 550
 551         if (err < 0) {
 552                 if (err == -EAGAIN)
 553                         netdev->stats.tx_dropped++;
 554                 else
 555                         netdev->stats.tx_errors++;
 556         }
 557
 558         return err;
 559 }
 560
 561 static int send_mcast_pkt(struct sk_buff *skb, struct net_device *netdev)
 562 {
 563         struct sk_buff *local_skb;
 564         struct lowpan_dev *entry;
 565         int err = 0;
 566
 567         rcu_read_lock();
 568
 569         list_for_each_entry_rcu(entry, &bt_6lowpan_devices, list) {
 570                 struct lowpan_peer *pentry;
 571                 struct lowpan_dev *dev;
 572
 573                 if (entry->netdev != netdev)
 574                         continue;
 575
 576                 dev = lowpan_dev(entry->netdev);
 577
 578                 list_for_each_entry_rcu(pentry, &dev->peers, list) {
 579                         int ret;
 580
 581                         local_skb = skb_clone(skb, GFP_ATOMIC);
 582
 583                         BT_DBG("xmit %s to %pMR type %d IP %pI6c chan %p",
 584                                netdev->name,
 585                                &pentry->chan->dst, pentry->chan->dst_type,
 586                                &pentry->peer_addr, pentry->chan);
 587                         ret = send_pkt(pentry->chan, local_skb, netdev);
 588                         if (ret < 0)
 589                                 err = ret;
 590
 591                         kfree_skb(local_skb);
 592                 }
 593         }
 594
 595         rcu_read_unlock();
 596
 597         return err;
 598 }
 599
 600 static netdev_tx_t bt_xmit(struct sk_buff *skb, struct net_device *netdev)
 601 {
 602         int err = 0;
 603         bdaddr_t addr;
 604         u8 addr_type;
 605
 606         /* We must take a copy of the skb before we modify/replace the ipv6
 607          * header as the header could be used elsewhere
 608          */
 609         skb = skb_unshare(skb, GFP_ATOMIC);
 610         if (!skb)
 611                 return NET_XMIT_DROP;
 612
 613         /* Return values from setup_header()
 614          *  <0 - error, packet is dropped
 615          *   0 - this is a multicast packet
 616          *   1 - this is unicast packet
 617          */
 618         err = setup_header(skb, netdev, &addr, &addr_type);
 619         if (err < 0) {
 620                 kfree_skb(skb);
 621                 return NET_XMIT_DROP;
 622         }
 623
 624         if (err) {
 625                 if (lowpan_cb(skb)->chan) {
 626                         BT_DBG("xmit %s to %pMR type %d IP %pI6c chan %p",
 627                                netdev->name, &addr, addr_type,
 628                                &lowpan_cb(skb)->addr, lowpan_cb(skb)->chan);
 629                         err = send_pkt(lowpan_cb(skb)->chan, skb, netdev);
 630                 } else {
 631                         err = -ENOENT;
 632                 }
 633         } else {
 634                 /* We need to send the packet to every device behind this
 635                  * interface.
 636                  */
 637                 err = send_mcast_pkt(skb, netdev);
 638         }
 639
 640         dev_kfree_skb(skb);
 641
 642         if (err)
 643                 BT_DBG("ERROR: xmit failed (%d)", err);
 644
 645         return err < 0 ? NET_XMIT_DROP : err;
 646 }
 647
 648 static struct lock_class_key bt_tx_busylock;
 649 static struct lock_class_key bt_netdev_xmit_lock_key;
 650
 651 static void bt_set_lockdep_class_one(struct net_device *dev,
 652                                      struct netdev_queue *txq,
 653                                      void *_unused)
 654 {
 655         lockdep_set_class(&txq->_xmit_lock, &bt_netdev_xmit_lock_key);
 656 }
 657
 658 static int bt_dev_init(struct net_device *dev)
 659 {
 660         netdev_for_each_tx_queue(dev, bt_set_lockdep_class_one, NULL);
 661         dev->qdisc_tx_busylock = &bt_tx_busylock;
 662
 663         return 0;
 664 }
 665
 666 static const struct net_device_ops netdev_ops = {
 667         .ndo_init               = bt_dev_init,
 668         .ndo_start_xmit         = bt_xmit,
 669 };
 670
 671 static struct header_ops header_ops = {
 672         .create = header_create,
 673 };
 674
 675 static void netdev_setup(struct net_device *dev)
 676 {
 677         dev->addr_len           = EUI64_ADDR_LEN;
 678         dev->type               = ARPHRD_6LOWPAN;
 679
 680         dev->hard_header_len    = 0;
 681         dev->needed_tailroom    = 0;
 682         dev->mtu                = IPV6_MIN_MTU;
 683         dev->tx_queue_len       = 0;
 684         dev->flags              = IFF_RUNNING | IFF_POINTOPOINT |
 685                                   IFF_MULTICAST;
 686         dev->watchdog_timeo     = 0;
 687
 688         dev->netdev_ops         = &netdev_ops;
 689         dev->header_ops         = &header_ops;
 690         dev->destructor         = free_netdev;
 691 }
 692
 693 static struct device_type bt_type = {
 694         .name   = "bluetooth",
 695 };
 696
 697 static void set_addr(u8 *eui, u8 *addr, u8 addr_type)
 698 {
 699         /* addr is the BT address in little-endian format */
 700         eui[0] = addr[5];
 701         eui[1] = addr[4];
 702         eui[2] = addr[3];
 703         eui[3] = 0xFF;
 704         eui[4] = 0xFE;
 705         eui[5] = addr[2];
 706         eui[6] = addr[1];
 707         eui[7] = addr[0];
 708
 709         /* Universal/local bit set, BT 6lowpan draft ch. 3.2.1 */
 710         if (addr_type == BDADDR_LE_PUBLIC)
 711                 eui[0] &= ~0x02;
 712         else
 713                 eui[0] |= 0x02;
 714
 715         BT_DBG("type %d addr %*phC", addr_type, 8, eui);
 716 }
 717
 718 static void set_dev_addr(struct net_device *netdev, bdaddr_t *addr,
 719                          u8 addr_type)
 720 {
 721         netdev->addr_assign_type = NET_ADDR_PERM;
 722         set_addr(netdev->dev_addr, addr->b, addr_type);
 723 }
 724
 725 static void ifup(struct net_device *netdev)
 726 {
 727         int err;
 728
 729         rtnl_lock();
 730         err = dev_open(netdev);
 731         if (err < 0)
 732                 BT_INFO("iface %s cannot be opened (%d)", netdev->name, err);
 733         rtnl_unlock();
 734 }
 735
 736 static void ifdown(struct net_device *netdev)
 737 {
 738         int err;
 739
 740         rtnl_lock();
 741         err = dev_close(netdev);
 742         if (err < 0)
 743                 BT_INFO("iface %s cannot be closed (%d)", netdev->name, err);
 744         rtnl_unlock();
 745 }
 746
 747 static void do_notify_peers(struct work_struct *work)
 748 {
 749         struct lowpan_dev *dev = container_of(work, struct lowpan_dev,
 750                                               notify_peers.work);
 751
 752         netdev_notify_peers(dev->netdev); /* send neighbour adv at startup */
 753 }
 754
 755 static bool is_bt_6lowpan(struct hci_conn *hcon)
 756 {
 757         if (hcon->type != LE_LINK)
 758                 return false;
 759
 760         if (!enable_6lowpan)
 761                 return false;
 762
 763         return true;
 764 }
 765
 766 static struct l2cap_chan *chan_create(void)
 767 {
 768         struct l2cap_chan *chan;
 769
 770         chan = l2cap_chan_create();
 771         if (!chan)
 772                 return NULL;
 773
 774         l2cap_chan_set_defaults(chan);
 775
 776         chan->chan_type = L2CAP_CHAN_CONN_ORIENTED;
 777         chan->mode = L2CAP_MODE_LE_FLOWCTL;
 778         chan->omtu = 65535;
 779         chan->imtu = chan->omtu;
 780
 781         return chan;
 782 }
 783
 784 static struct l2cap_chan *chan_open(struct l2cap_chan *pchan)
 785 {
 786         struct l2cap_chan *chan;
 787
 788         chan = chan_create();
 789         if (!chan)
 790                 return NULL;
 791
 792         chan->remote_mps = chan->omtu;
 793         chan->mps = chan->omtu;
 794
 795         chan->state = BT_CONNECTED;
 796
 797         return chan;
 798 }
 799
 800 static void set_ip_addr_bits(u8 addr_type, u8 *addr)
 801 {
 802         if (addr_type == BDADDR_LE_PUBLIC)
 803                 *addr |= 0x02;
 804         else
 805                 *addr &= ~0x02;
 806 }
 807
 808 static struct l2cap_chan *add_peer_chan(struct l2cap_chan *chan,
 809                                         struct lowpan_dev *dev)
 810 {
 811         struct lowpan_peer *peer;
 812
 813         peer = kzalloc(sizeof(*peer), GFP_ATOMIC);
 814         if (!peer)
 815                 return NULL;
 816
 817         peer->chan = chan;
 818         memset(&peer->peer_addr, 0, sizeof(struct in6_addr));
 819
 820         /* RFC 2464 ch. 5 */
 821         peer->peer_addr.s6_addr[0] = 0xFE;
 822         peer->peer_addr.s6_addr[1] = 0x80;
 823         set_addr((u8 *)&peer->peer_addr.s6_addr + 8, chan->dst.b,
 824                  chan->dst_type);
 825
 826         memcpy(&peer->eui64_addr, (u8 *)&peer->peer_addr.s6_addr + 8,
 827                EUI64_ADDR_LEN);
 828
 829         /* IPv6 address needs to have the U/L bit set properly so toggle
 830          * it back here.
 831          */
 832         set_ip_addr_bits(chan->dst_type, (u8 *)&peer->peer_addr.s6_addr + 8);
 833
 834         spin_lock(&devices_lock);
 835         INIT_LIST_HEAD(&peer->list);
 836         peer_add(dev, peer);
 837         spin_unlock(&devices_lock);
 838
 839         /* Notifying peers about us needs to be done without locks held */
 840         INIT_DELAYED_WORK(&dev->notify_peers, do_notify_peers);
 841         schedule_delayed_work(&dev->notify_peers, msecs_to_jiffies(100));
 842
 843         return peer->chan;
 844 }
 845
 846 static int setup_netdev(struct l2cap_chan *chan, struct lowpan_dev **dev)
 847 {
 848         struct net_device *netdev;
 849         int err = 0;
 850
 851         netdev = alloc_netdev(LOWPAN_PRIV_SIZE(sizeof(struct lowpan_dev)),
 852                               IFACE_NAME_TEMPLATE, NET_NAME_UNKNOWN,
 853                               netdev_setup);
 854         if (!netdev)
 855                 return -ENOMEM;
 856
 857         set_dev_addr(netdev, &chan->src, chan->src_type);
 858
 859         netdev->netdev_ops = &netdev_ops;
 860         SET_NETDEV_DEV(netdev, &chan->conn->hcon->hdev->dev);
 861         SET_NETDEV_DEVTYPE(netdev, &bt_type);
 862
 863         *dev = lowpan_dev(netdev);
 864         (*dev)->netdev = netdev;
 865         (*dev)->hdev = chan->conn->hcon->hdev;
 866         INIT_LIST_HEAD(&(*dev)->peers);
 867
 868         spin_lock(&devices_lock);
 869         INIT_LIST_HEAD(&(*dev)->list);
 870         list_add_rcu(&(*dev)->list, &bt_6lowpan_devices);
 871         spin_unlock(&devices_lock);
 872
 873         lowpan_netdev_setup(netdev, LOWPAN_LLTYPE_BTLE);
 874
 875         err = register_netdev(netdev);
 876         if (err < 0) {
 877                 BT_INFO("register_netdev failed %d", err);
 878                 spin_lock(&devices_lock);
 879                 list_del_rcu(&(*dev)->list);
 880                 spin_unlock(&devices_lock);
 881                 free_netdev(netdev);
 882                 goto out;
 883         }
 884
 885         BT_DBG("ifindex %d peer bdaddr %pMR type %d my addr %pMR type %d",
 886                netdev->ifindex, &chan->dst, chan->dst_type,
 887                &chan->src, chan->src_type);
 888         set_bit(__LINK_STATE_PRESENT, &netdev->state);
 889
 890         return 0;
 891
 892 out:
 893         return err;
 894 }
 895
 896 static inline void chan_ready_cb(struct l2cap_chan *chan)
 897 {
 898         struct lowpan_dev *dev;
 899
 900         dev = lookup_dev(chan->conn);
 901
 902         BT_DBG("chan %p conn %p dev %p", chan, chan->conn, dev);
 903
 904         if (!dev) {
 905                 if (setup_netdev(chan, &dev) < 0) {
 906                         l2cap_chan_del(chan, -ENOENT);
 907                         return;
 908                 }
 909         }
 910
 911         if (!try_module_get(THIS_MODULE))
 912                 return;
 913
 914         add_peer_chan(chan, dev);
 915         ifup(dev->netdev);
 916 }
 917
 918 static inline struct l2cap_chan *chan_new_conn_cb(struct l2cap_chan *pchan)
 919 {
 920         struct l2cap_chan *chan;
 921
 922         chan = chan_open(pchan);
 923         chan->ops = pchan->ops;
 924
 925         BT_DBG("chan %p pchan %p", chan, pchan);
 926
 927         return chan;
 928 }
 929
 930 static void delete_netdev(struct work_struct *work)
 931 {
 932         struct lowpan_dev *entry = container_of(work, struct lowpan_dev,
 933                                                 delete_netdev);
 934
 935         unregister_netdev(entry->netdev);
 936
 937         /* The entry pointer is deleted by the netdev destructor. */
 938 }
 939
 940 static void chan_close_cb(struct l2cap_chan *chan)
 941 {
 942         struct lowpan_dev *entry;
 943         struct lowpan_dev *dev = NULL;
 944         struct lowpan_peer *peer;
 945         int err = -ENOENT;
 946         bool last = false, remove = true;
 947
 948         BT_DBG("chan %p conn %p", chan, chan->conn);
 949
 950         if (chan->conn && chan->conn->hcon) {
 951                 if (!is_bt_6lowpan(chan->conn->hcon))
 952                         return;
 953
 954                 /* If conn is set, then the netdev is also there and we should
 955                  * not remove it.
 956                  */
 957                 remove = false;
 958         }
 959
 960         spin_lock(&devices_lock);
 961
 962         list_for_each_entry_rcu(entry, &bt_6lowpan_devices, list) {
 963                 dev = lowpan_dev(entry->netdev);
 964                 peer = __peer_lookup_chan(dev, chan);
 965                 if (peer) {
 966                         last = peer_del(dev, peer);
 967                         err = 0;
 968
 969                         BT_DBG("dev %p removing %speer %p", dev,
 970                                last ? "last " : "1 ", peer);
 971                         BT_DBG("chan %p orig refcnt %d", chan,
 972                                atomic_read(&chan->kref.refcount));
 973
 974                         l2cap_chan_put(chan);
 975                         break;
 976                 }
 977         }
 978
 979         if (!err && last && dev && !atomic_read(&dev->peer_count)) {
 980                 spin_unlock(&devices_lock);
 981
 982                 cancel_delayed_work_sync(&dev->notify_peers);
 983
 984                 ifdown(dev->netdev);
 985
 986                 if (remove) {
 987                         INIT_WORK(&entry->delete_netdev, delete_netdev);
 988                         schedule_work(&entry->delete_netdev);
 989                 }
 990         } else {
 991                 spin_unlock(&devices_lock);
 992         }
 993
 994         return;
 995 }
 996
 997 static void chan_state_change_cb(struct l2cap_chan *chan, int state, int err)
 998 {
 999         BT_DBG("chan %p conn %p state %s err %d", chan, chan->conn,
1000                state_to_string(state), err);
1001 }
1002
1003 static struct sk_buff *chan_alloc_skb_cb(struct l2cap_chan *chan,
1004                                          unsigned long hdr_len,
1005                                          unsigned long len, int nb)
1006 {
1007         /* Note that we must allocate using GFP_ATOMIC here as
1008          * this function is called originally from netdev hard xmit
1009          * function in atomic context.
1010          */
1011         return bt_skb_alloc(hdr_len + len, GFP_ATOMIC);
1012 }
1013
1014 static void chan_suspend_cb(struct l2cap_chan *chan)
1015 {
1016         struct sk_buff *skb = chan->data;
1017
1018         BT_DBG("chan %p conn %p skb %p", chan, chan->conn, skb);
1019
1020         if (!skb)
1021                 return;
1022
1023         lowpan_cb(skb)->status = -EAGAIN;
1024 }
1025
1026 static void chan_resume_cb(struct l2cap_chan *chan)
1027 {
1028         struct sk_buff *skb = chan->data;
1029
1030         BT_DBG("chan %p conn %p skb %p", chan, chan->conn, skb);
1031
1032         if (!skb)
1033                 return;
1034
1035         lowpan_cb(skb)->status = 0;
1036 }
1037
1038 static long chan_get_sndtimeo_cb(struct l2cap_chan *chan)
1039 {
1040         return L2CAP_CONN_TIMEOUT;
1041 }
1042
1043 static const struct l2cap_ops bt_6lowpan_chan_ops = {
1044         .name                   = "L2CAP 6LoWPAN channel",
1045         .new_connection         = chan_new_conn_cb,
1046         .recv                   = chan_recv_cb,
1047         .close                  = chan_close_cb,
1048         .state_change           = chan_state_change_cb,
1049         .ready                  = chan_ready_cb,
1050         .resume                 = chan_resume_cb,
1051         .suspend                = chan_suspend_cb,
1052         .get_sndtimeo           = chan_get_sndtimeo_cb,
1053         .alloc_skb              = chan_alloc_skb_cb,
1054
1055         .teardown               = l2cap_chan_no_teardown,
1056         .defer                  = l2cap_chan_no_defer,
1057         .set_shutdown           = l2cap_chan_no_set_shutdown,
1058 };
1059
1060 static inline __u8 bdaddr_type(__u8 type)
1061 {
1062         if (type == ADDR_LE_DEV_PUBLIC)
1063                 return BDADDR_LE_PUBLIC;
1064         else
1065                 return BDADDR_LE_RANDOM;
1066 }
1067
1068 static struct l2cap_chan *chan_get(void)
1069 {
1070         struct l2cap_chan *pchan;
1071
1072         pchan = chan_create();
1073         if (!pchan)
1074                 return NULL;
1075
1076         pchan->ops = &bt_6lowpan_chan_ops;
1077
1078         return pchan;
1079 }
1080
1081 static int bt_6lowpan_connect(bdaddr_t *addr, u8 dst_type)
1082 {
1083         struct l2cap_chan *pchan;
1084         int err;
1085
1086         pchan = chan_get();
1087         if (!pchan)
1088                 return -EINVAL;
1089
1090         err = l2cap_chan_connect(pchan, cpu_to_le16(L2CAP_PSM_IPSP), 0,
1091                                  addr, dst_type);
1092
1093         BT_DBG("chan %p err %d", pchan, err);
1094         if (err < 0)
1095                 l2cap_chan_put(pchan);
1096
1097         return err;
1098 }
1099
1100 static int bt_6lowpan_disconnect(struct l2cap_conn *conn, u8 dst_type)
1101 {
1102         struct lowpan_peer *peer;
1103
1104         BT_DBG("conn %p dst type %d", conn, dst_type);
1105
1106         peer = lookup_peer(conn);
1107         if (!peer)
1108                 return -ENOENT;
1109
1110         BT_DBG("peer %p chan %p", peer, peer->chan);
1111
1112         l2cap_chan_close(peer->chan, ENOENT);
1113
1114         return 0;
1115 }
1116
1117 static struct l2cap_chan *bt_6lowpan_listen(void)
1118 {
1119         bdaddr_t *addr = BDADDR_ANY;
1120         struct l2cap_chan *pchan;
1121         int err;
1122
1123         if (!enable_6lowpan)
1124                 return NULL;
1125
1126         pchan = chan_get();
1127         if (!pchan)
1128                 return NULL;
1129
1130         pchan->state = BT_LISTEN;
1131         pchan->src_type = BDADDR_LE_PUBLIC;
1132
1133         atomic_set(&pchan->nesting, L2CAP_NESTING_PARENT);
1134
1135         BT_DBG("chan %p src type %d", pchan, pchan->src_type);
1136
1137         err = l2cap_add_psm(pchan, addr, cpu_to_le16(L2CAP_PSM_IPSP));
1138         if (err) {
1139                 l2cap_chan_put(pchan);
1140                 BT_ERR("psm cannot be added err %d", err);
1141                 return NULL;
1142         }
1143
1144         return pchan;
1145 }
1146
1147 static int get_l2cap_conn(char *buf, bdaddr_t *addr, u8 *addr_type,
1148                           struct l2cap_conn **conn)
1149 {
1150         struct hci_conn *hcon;
1151         struct hci_dev *hdev;
1152         bdaddr_t *src = BDADDR_ANY;
1153         int n;
1154
1155         n = sscanf(buf, "%hhx:%hhx:%hhx:%hhx:%hhx:%hhx %hhu",
1156                    &addr->b[5], &addr->b[4], &addr->b[3],
1157                    &addr->b[2], &addr->b[1], &addr->b[0],
1158                    addr_type);
1159
1160         if (n < 7)
1161                 return -EINVAL;
1162
1163         hdev = hci_get_route(addr, src);
1164         if (!hdev)
1165                 return -ENOENT;
1166
1167         hci_dev_lock(hdev);
1168         hcon = hci_conn_hash_lookup_ba(hdev, LE_LINK, addr);
1169         hci_dev_unlock(hdev);
1170
1171         if (!hcon)
1172                 return -ENOENT;
1173
1174         *conn = (struct l2cap_conn *)hcon->l2cap_data;
1175
1176         BT_DBG("conn %p dst %pMR type %d", *conn, &hcon->dst, hcon->dst_type);
1177
1178         return 0;
1179 }
1180
1181 static void disconnect_all_peers(void)
1182 {
1183         struct lowpan_dev *entry;
1184         struct lowpan_peer *peer, *tmp_peer, *new_peer;
1185         struct list_head peers;
1186
1187         INIT_LIST_HEAD(&peers);
1188
1189         /* We make a separate list of peers as the close_cb() will
1190          * modify the device peers list so it is better not to mess
1191          * with the same list at the same time.
1192          */
1193
1194         rcu_read_lock();
1195
1196         list_for_each_entry_rcu(entry, &bt_6lowpan_devices, list) {
1197                 list_for_each_entry_rcu(peer, &entry->peers, list) {
1198                         new_peer = kmalloc(sizeof(*new_peer), GFP_ATOMIC);
1199                         if (!new_peer)
1200                                 break;
1201
1202                         new_peer->chan = peer->chan;
1203                         INIT_LIST_HEAD(&new_peer->list);
1204
1205                         list_add(&new_peer->list, &peers);
1206                 }
1207         }
1208
1209         rcu_read_unlock();
1210
1211         spin_lock(&devices_lock);
1212         list_for_each_entry_safe(peer, tmp_peer, &peers, list) {
1213                 l2cap_chan_close(peer->chan, ENOENT);
1214
1215                 list_del_rcu(&peer->list);
1216                 kfree_rcu(peer, rcu);
1217         }
1218         spin_unlock(&devices_lock);
1219 }
1220
1221 struct set_enable {
1222         struct work_struct work;
1223         bool flag;
1224 };
1225
1226 static void do_enable_set(struct work_struct *work)
1227 {
1228         struct set_enable *set_enable = container_of(work,
1229                                                      struct set_enable, work);
1230
1231         if (!set_enable->flag || enable_6lowpan != set_enable->flag)
1232                 /* Disconnect existing connections if 6lowpan is
1233                  * disabled
1234                  */
1235                 disconnect_all_peers();
1236
1237         enable_6lowpan = set_enable->flag;
1238
1239         if (listen_chan) {
1240                 l2cap_chan_close(listen_chan, 0);
1241                 l2cap_chan_put(listen_chan);
1242         }
1243
1244         listen_chan = bt_6lowpan_listen();
1245
1246         kfree(set_enable);
1247 }
1248
1249 static int lowpan_enable_set(void *data, u64 val)
1250 {
1251         struct set_enable *set_enable;
1252
1253         set_enable = kzalloc(sizeof(*set_enable), GFP_KERNEL);
1254         if (!set_enable)
1255                 return -ENOMEM;
1256
1257         set_enable->flag = !!val;
1258         INIT_WORK(&set_enable->work, do_enable_set);
1259
1260         schedule_work(&set_enable->work);
1261
1262         return 0;
1263 }
1264
1265 static int lowpan_enable_get(void *data, u64 *val)
1266 {
1267         *val = enable_6lowpan;
1268         return 0;
1269 }
1270
1271 DEFINE_SIMPLE_ATTRIBUTE(lowpan_enable_fops, lowpan_enable_get,
1272                         lowpan_enable_set, "%llu\n");
1273
1274 static ssize_t lowpan_control_write(struct file *fp,
1275                                     const char __user *user_buffer,
1276                                     size_t count,
1277                                     loff_t *position)
1278 {
1279         char buf[32];
1280         size_t buf_size = min(count, sizeof(buf) - 1);
1281         int ret;
1282         bdaddr_t addr;
1283         u8 addr_type;
1284         struct l2cap_conn *conn = NULL;
1285
1286         if (copy_from_user(buf, user_buffer, buf_size))
1287                 return -EFAULT;
1288
1289         buf[buf_size] = '\0';
1290
1291         if (memcmp(buf, "connect ", 8) == 0) {
1292                 ret = get_l2cap_conn(&buf[8], &addr, &addr_type, &conn);
1293                 if (ret == -EINVAL)
1294                         return ret;
1295
1296                 if (listen_chan) {
1297                         l2cap_chan_close(listen_chan, 0);
1298                         l2cap_chan_put(listen_chan);
1299                         listen_chan = NULL;
1300                 }
1301
1302                 if (conn) {
1303                         struct lowpan_peer *peer;
1304
1305                         if (!is_bt_6lowpan(conn->hcon))
1306                                 return -EINVAL;
1307
1308                         peer = lookup_peer(conn);
1309                         if (peer) {
1310                                 BT_DBG("6LoWPAN connection already exists");
1311                                 return -EALREADY;
1312                         }
1313
1314                         BT_DBG("conn %p dst %pMR type %d user %d", conn,
1315                                &conn->hcon->dst, conn->hcon->dst_type,
1316                                addr_type);
1317                 }
1318
1319                 ret = bt_6lowpan_connect(&addr, addr_type);
1320                 if (ret < 0)
1321                         return ret;
1322
1323                 return count;
1324         }
1325
1326         if (memcmp(buf, "disconnect ", 11) == 0) {
1327                 ret = get_l2cap_conn(&buf[11], &addr, &addr_type, &conn);
1328                 if (ret < 0)
1329                         return ret;
1330
1331                 ret = bt_6lowpan_disconnect(conn, addr_type);
1332                 if (ret < 0)
1333                         return ret;
1334
1335                 return count;
1336         }
1337
1338         return count;
1339 }
1340
1341 static int lowpan_control_show(struct seq_file *f, void *ptr)
1342 {
1343         struct lowpan_dev *entry;
1344         struct lowpan_peer *peer;
1345
1346         spin_lock(&devices_lock);
1347
1348         list_for_each_entry(entry, &bt_6lowpan_devices, list) {
1349                 list_for_each_entry(peer, &entry->peers, list)
1350                         seq_printf(f, "%pMR (type %u)\n",
1351                                    &peer->chan->dst, peer->chan->dst_type);
1352         }
1353
1354         spin_unlock(&devices_lock);
1355
1356         return 0;
1357 }
1358
1359 static int lowpan_control_open(struct inode *inode, struct file *file)
1360 {
1361         return single_open(file, lowpan_control_show, inode->i_private);
1362 }
1363
1364 static const struct file_operations lowpan_control_fops = {
1365         .open           = lowpan_control_open,
1366         .read           = seq_read,
1367         .write          = lowpan_control_write,
1368         .llseek         = seq_lseek,
1369         .release        = single_release,
1370 };
1371
1372 static void disconnect_devices(void)
1373 {
1374         struct lowpan_dev *entry, *tmp, *new_dev;
1375         struct list_head devices;
1376
1377         INIT_LIST_HEAD(&devices);
1378
1379         /* We make a separate list of devices because the unregister_netdev()
1380          * will call device_event() which will also want to modify the same
1381          * devices list.
1382          */
1383
1384         rcu_read_lock();
1385
1386         list_for_each_entry_rcu(entry, &bt_6lowpan_devices, list) {
1387                 new_dev = kmalloc(sizeof(*new_dev), GFP_ATOMIC);
1388                 if (!new_dev)
1389                         break;
1390
1391                 new_dev->netdev = entry->netdev;
1392                 INIT_LIST_HEAD(&new_dev->list);
1393
1394                 list_add_rcu(&new_dev->list, &devices);
1395         }
1396
1397         rcu_read_unlock();
1398
1399         list_for_each_entry_safe(entry, tmp, &devices, list) {
1400                 ifdown(entry->netdev);
1401                 BT_DBG("Unregistering netdev %s %p",
1402                        entry->netdev->name, entry->netdev);
1403                 unregister_netdev(entry->netdev);
1404                 kfree(entry);
1405         }
1406 }
1407
1408 static int device_event(struct notifier_block *unused,
1409                         unsigned long event, void *ptr)
1410 {
1411         struct net_device *netdev = netdev_notifier_info_to_dev(ptr);
1412         struct lowpan_dev *entry;
1413
1414         if (netdev->type != ARPHRD_6LOWPAN)
1415                 return NOTIFY_DONE;
1416
1417         switch (event) {
1418         case NETDEV_UNREGISTER:
1419                 spin_lock(&devices_lock);
1420                 list_for_each_entry(entry, &bt_6lowpan_devices, list) {
1421                         if (entry->netdev == netdev) {
1422                                 BT_DBG("Unregistered netdev %s %p",
1423                                        netdev->name, netdev);
1424                                 list_del(&entry->list);
1425                                 break;
1426                         }
1427                 }
1428                 spin_unlock(&devices_lock);
1429                 break;
1430         }
1431
1432         return NOTIFY_DONE;
1433 }
1434
1435 static struct notifier_block bt_6lowpan_dev_notifier = {
1436         .notifier_call = device_event,
1437 };
1438
1439 static int __init bt_6lowpan_init(void)
1440 {
1441         lowpan_enable_debugfs = debugfs_create_file("6lowpan_enable", 0644,
1442                                                     bt_debugfs, NULL,
1443                                                     &lowpan_enable_fops);
1444         lowpan_control_debugfs = debugfs_create_file("6lowpan_control", 0644,
1445                                                      bt_debugfs, NULL,
1446                                                      &lowpan_control_fops);
1447
1448         return register_netdevice_notifier(&bt_6lowpan_dev_notifier);
1449 }
1450
1451 static void __exit bt_6lowpan_exit(void)
1452 {
1453         debugfs_remove(lowpan_enable_debugfs);
1454         debugfs_remove(lowpan_control_debugfs);
1455
1456         if (listen_chan) {
1457                 l2cap_chan_close(listen_chan, 0);
1458                 l2cap_chan_put(listen_chan);
1459         }
1460
1461         disconnect_devices();
1462
1463         unregister_netdevice_notifier(&bt_6lowpan_dev_notifier);
1464 }
1465
1466 module_init(bt_6lowpan_init);
1467 module_exit(bt_6lowpan_exit);
1468
1469 MODULE_AUTHOR("Jukka Rissanen <jukka.rissanen@linux.intel.com>");
1470 MODULE_DESCRIPTION("Bluetooth 6LoWPAN");
1471 MODULE_VERSION(VERSION);
1472 MODULE_LICENSE("GPL");