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_psm_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 /* If psm is set to 0 (default value), then 6lowpan is disabled.
  59  * Other values are used to indicate a Protocol Service Multiplexer
  60  * value for 6lowpan.
  61  */
  62 static u16 psm_6lowpan;
  63
  64 /* We are listening incoming connections via this channel
  65  */
  66 static struct l2cap_chan *listen_chan;
  67
  68 struct lowpan_peer {
  69         struct list_head list;
  70         struct rcu_head rcu;
  71         struct l2cap_chan *chan;
  72
  73         /* peer addresses in various formats */
  74         unsigned char eui64_addr[EUI64_ADDR_LEN];
  75         struct in6_addr peer_addr;
  76 };
  77
  78 struct lowpan_dev {
  79         struct list_head list;
  80
  81         struct hci_dev *hdev;
  82         struct net_device *netdev;
  83         struct list_head peers;
  84         atomic_t peer_count; /* number of items in peers list */
  85
  86         struct work_struct delete_netdev;
  87         struct delayed_work notify_peers;
  88 };
  89
  90 static inline struct lowpan_dev *lowpan_dev(const struct net_device *netdev)
  91 {
  92         return netdev_priv(netdev);
  93 }
  94
  95 static inline void peer_add(struct lowpan_dev *dev, struct lowpan_peer *peer)
  96 {
  97         list_add_rcu(&peer->list, &dev->peers);
  98         atomic_inc(&dev->peer_count);
  99 }
 100
 101 static inline bool peer_del(struct lowpan_dev *dev, struct lowpan_peer *peer)
 102 {
 103         list_del_rcu(&peer->list);
 104         kfree_rcu(peer, rcu);
 105
 106         module_put(THIS_MODULE);
 107
 108         if (atomic_dec_and_test(&dev->peer_count)) {
 109                 BT_DBG("last peer");
 110                 return true;
 111         }
 112
 113         return false;
 114 }
 115
 116 static inline struct lowpan_peer *peer_lookup_ba(struct lowpan_dev *dev,
 117                                                  bdaddr_t *ba, __u8 type)
 118 {
 119         struct lowpan_peer *peer;
 120
 121         BT_DBG("peers %d addr %pMR type %d", atomic_read(&dev->peer_count),
 122                ba, type);
 123
 124         rcu_read_lock();
 125
 126         list_for_each_entry_rcu(peer, &dev->peers, list) {
 127                 BT_DBG("dst addr %pMR dst type %d",
 128                        &peer->chan->dst, peer->chan->dst_type);
 129
 130                 if (bacmp(&peer->chan->dst, ba))
 131                         continue;
 132
 133                 if (type == peer->chan->dst_type) {
 134                         rcu_read_unlock();
 135                         return peer;
 136                 }
 137         }
 138
 139         rcu_read_unlock();
 140
 141         return NULL;
 142 }
 143
 144 static inline struct lowpan_peer *__peer_lookup_chan(struct lowpan_dev *dev,
 145                                                      struct l2cap_chan *chan)
 146 {
 147         struct lowpan_peer *peer;
 148
 149         list_for_each_entry_rcu(peer, &dev->peers, list) {
 150                 if (peer->chan == chan)
 151                         return peer;
 152         }
 153
 154         return NULL;
 155 }
 156
 157 static inline struct lowpan_peer *__peer_lookup_conn(struct lowpan_dev *dev,
 158                                                      struct l2cap_conn *conn)
 159 {
 160         struct lowpan_peer *peer;
 161
 162         list_for_each_entry_rcu(peer, &dev->peers, list) {
 163                 if (peer->chan->conn == conn)
 164                         return peer;
 165         }
 166
 167         return NULL;
 168 }
 169
 170 static inline struct lowpan_peer *peer_lookup_dst(struct lowpan_dev *dev,
 171                                                   struct in6_addr *daddr,
 172                                                   struct sk_buff *skb)
 173 {
 174         struct lowpan_peer *peer;
 175         struct in6_addr *nexthop;
 176         struct rt6_info *rt = (struct rt6_info *)skb_dst(skb);
 177         int count = atomic_read(&dev->peer_count);
 178
 179         BT_DBG("peers %d addr %pI6c rt %p", count, daddr, rt);
 180
 181         /* If we have multiple 6lowpan peers, then check where we should
 182          * send the packet. If only one peer exists, then we can send the
 183          * packet right away.
 184          */
 185         if (count == 1) {
 186                 rcu_read_lock();
 187                 peer = list_first_or_null_rcu(&dev->peers, struct lowpan_peer,
 188                                               list);
 189                 rcu_read_unlock();
 190                 return peer;
 191         }
 192
 193         if (!rt) {
 194                 nexthop = &lowpan_cb(skb)->gw;
 195
 196                 if (ipv6_addr_any(nexthop))
 197                         return NULL;
 198         } else {
 199                 nexthop = rt6_nexthop(rt);
 200
 201                 /* We need to remember the address because it is needed
 202                  * by bt_xmit() when sending the packet. In bt_xmit(), the
 203                  * destination routing info is not set.
 204                  */
 205                 memcpy(&lowpan_cb(skb)->gw, nexthop, sizeof(struct in6_addr));
 206         }
 207
 208         BT_DBG("gw %pI6c", nexthop);
 209
 210         rcu_read_lock();
 211
 212         list_for_each_entry_rcu(peer, &dev->peers, list) {
 213                 BT_DBG("dst addr %pMR dst type %d ip %pI6c",
 214                        &peer->chan->dst, peer->chan->dst_type,
 215                        &peer->peer_addr);
 216
 217                 if (!ipv6_addr_cmp(&peer->peer_addr, nexthop)) {
 218                         rcu_read_unlock();
 219                         return peer;
 220                 }
 221         }
 222
 223         rcu_read_unlock();
 224
 225         return NULL;
 226 }
 227
 228 static struct lowpan_peer *lookup_peer(struct l2cap_conn *conn)
 229 {
 230         struct lowpan_dev *entry;
 231         struct lowpan_peer *peer = NULL;
 232
 233         rcu_read_lock();
 234
 235         list_for_each_entry_rcu(entry, &bt_6lowpan_devices, list) {
 236                 peer = __peer_lookup_conn(entry, conn);
 237                 if (peer)
 238                         break;
 239         }
 240
 241         rcu_read_unlock();
 242
 243         return peer;
 244 }
 245
 246 static struct lowpan_dev *lookup_dev(struct l2cap_conn *conn)
 247 {
 248         struct lowpan_dev *entry;
 249         struct lowpan_dev *dev = NULL;
 250
 251         rcu_read_lock();
 252
 253         list_for_each_entry_rcu(entry, &bt_6lowpan_devices, list) {
 254                 if (conn->hcon->hdev == entry->hdev) {
 255                         dev = entry;
 256                         break;
 257                 }
 258         }
 259
 260         rcu_read_unlock();
 261
 262         return dev;
 263 }
 264
 265 static int give_skb_to_upper(struct sk_buff *skb, struct net_device *dev)
 266 {
 267         struct sk_buff *skb_cp;
 268
 269         skb_cp = skb_copy(skb, GFP_ATOMIC);
 270         if (!skb_cp)
 271                 return NET_RX_DROP;
 272
 273         return netif_rx(skb_cp);
 274 }
 275
 276 static int iphc_decompress(struct sk_buff *skb, struct net_device *netdev,
 277                            struct l2cap_chan *chan)
 278 {
 279         const u8 *saddr, *daddr;
 280         u8 iphc0, iphc1;
 281         struct lowpan_dev *dev;
 282         struct lowpan_peer *peer;
 283
 284         dev = lowpan_dev(netdev);
 285
 286         rcu_read_lock();
 287         peer = __peer_lookup_chan(dev, chan);
 288         rcu_read_unlock();
 289         if (!peer)
 290                 return -EINVAL;
 291
 292         saddr = peer->eui64_addr;
 293         daddr = dev->netdev->dev_addr;
 294
 295         /* at least two bytes will be used for the encoding */
 296         if (skb->len < 2)
 297                 return -EINVAL;
 298
 299         if (lowpan_fetch_skb_u8(skb, &iphc0))
 300                 return -EINVAL;
 301
 302         if (lowpan_fetch_skb_u8(skb, &iphc1))
 303                 return -EINVAL;
 304
 305         return lowpan_header_decompress(skb, netdev,
 306                                         saddr, IEEE802154_ADDR_LONG,
 307                                         EUI64_ADDR_LEN, daddr,
 308                                         IEEE802154_ADDR_LONG, EUI64_ADDR_LEN,
 309                                         iphc0, iphc1);
 310
 311 }
 312
 313 static int recv_pkt(struct sk_buff *skb, struct net_device *dev,
 314                     struct l2cap_chan *chan)
 315 {
 316         struct sk_buff *local_skb;
 317         int ret;
 318
 319         if (!netif_running(dev))
 320                 goto drop;
 321
 322         if (dev->type != ARPHRD_6LOWPAN)
 323                 goto drop;
 324
 325         skb = skb_share_check(skb, GFP_ATOMIC);
 326         if (!skb)
 327                 goto drop;
 328
 329         /* check that it's our buffer */
 330         if (skb->data[0] == LOWPAN_DISPATCH_IPV6) {
 331                 /* Copy the packet so that the IPv6 header is
 332                  * properly aligned.
 333                  */
 334                 local_skb = skb_copy_expand(skb, NET_SKB_PAD - 1,
 335                                             skb_tailroom(skb), GFP_ATOMIC);
 336                 if (!local_skb)
 337                         goto drop;
 338
 339                 local_skb->protocol = htons(ETH_P_IPV6);
 340                 local_skb->pkt_type = PACKET_HOST;
 341
 342                 skb_reset_network_header(local_skb);
 343                 skb_set_transport_header(local_skb, sizeof(struct ipv6hdr));
 344
 345                 if (give_skb_to_upper(local_skb, dev) != NET_RX_SUCCESS) {
 346                         kfree_skb(local_skb);
 347                         goto drop;
 348                 }
 349
 350                 dev->stats.rx_bytes += skb->len;
 351                 dev->stats.rx_packets++;
 352
 353                 consume_skb(local_skb);
 354                 consume_skb(skb);
 355         } else {
 356                 switch (skb->data[0] & 0xe0) {
 357                 case LOWPAN_DISPATCH_IPHC:      /* ipv6 datagram */
 358                         local_skb = skb_clone(skb, GFP_ATOMIC);
 359                         if (!local_skb)
 360                                 goto drop;
 361
 362                         ret = iphc_decompress(local_skb, dev, chan);
 363                         if (ret < 0) {
 364                                 kfree_skb(local_skb);
 365                                 goto drop;
 366                         }
 367
 368                         local_skb->protocol = htons(ETH_P_IPV6);
 369                         local_skb->pkt_type = PACKET_HOST;
 370                         local_skb->dev = dev;
 371
 372                         if (give_skb_to_upper(local_skb, dev)
 373                                         != NET_RX_SUCCESS) {
 374                                 kfree_skb(local_skb);
 375                                 goto drop;
 376                         }
 377
 378                         dev->stats.rx_bytes += skb->len;
 379                         dev->stats.rx_packets++;
 380
 381                         consume_skb(local_skb);
 382                         consume_skb(skb);
 383                         break;
 384                 default:
 385                         break;
 386                 }
 387         }
 388
 389         return NET_RX_SUCCESS;
 390
 391 drop:
 392         dev->stats.rx_dropped++;
 393         return NET_RX_DROP;
 394 }
 395
 396 /* Packet from BT LE device */
 397 static int chan_recv_cb(struct l2cap_chan *chan, struct sk_buff *skb)
 398 {
 399         struct lowpan_dev *dev;
 400         struct lowpan_peer *peer;
 401         int err;
 402
 403         peer = lookup_peer(chan->conn);
 404         if (!peer)
 405                 return -ENOENT;
 406
 407         dev = lookup_dev(chan->conn);
 408         if (!dev || !dev->netdev)
 409                 return -ENOENT;
 410
 411         err = recv_pkt(skb, dev->netdev, chan);
 412         if (err) {
 413                 BT_DBG("recv pkt %d", err);
 414                 err = -EAGAIN;
 415         }
 416
 417         return err;
 418 }
 419
 420 static u8 get_addr_type_from_eui64(u8 byte)
 421 {
 422         /* Is universal(0) or local(1) bit */
 423         return ((byte & 0x02) ? BDADDR_LE_RANDOM : BDADDR_LE_PUBLIC);
 424 }
 425
 426 static void copy_to_bdaddr(struct in6_addr *ip6_daddr, bdaddr_t *addr)
 427 {
 428         u8 *eui64 = ip6_daddr->s6_addr + 8;
 429
 430         addr->b[0] = eui64[7];
 431         addr->b[1] = eui64[6];
 432         addr->b[2] = eui64[5];
 433         addr->b[3] = eui64[2];
 434         addr->b[4] = eui64[1];
 435         addr->b[5] = eui64[0];
 436 }
 437
 438 static void convert_dest_bdaddr(struct in6_addr *ip6_daddr,
 439                                 bdaddr_t *addr, u8 *addr_type)
 440 {
 441         copy_to_bdaddr(ip6_daddr, addr);
 442
 443         /* We need to toggle the U/L bit that we got from IPv6 address
 444          * so that we get the proper address and type of the BD address.
 445          */
 446         addr->b[5] ^= 0x02;
 447
 448         *addr_type = get_addr_type_from_eui64(addr->b[5]);
 449 }
 450
 451 static int setup_header(struct sk_buff *skb, struct net_device *netdev,
 452                         bdaddr_t *peer_addr, u8 *peer_addr_type)
 453 {
 454         struct in6_addr ipv6_daddr;
 455         struct lowpan_dev *dev;
 456         struct lowpan_peer *peer;
 457         bdaddr_t addr, *any = BDADDR_ANY;
 458         u8 *daddr = any->b;
 459         int err, status = 0;
 460
 461         dev = lowpan_dev(netdev);
 462
 463         memcpy(&ipv6_daddr, &lowpan_cb(skb)->addr, sizeof(ipv6_daddr));
 464
 465         if (ipv6_addr_is_multicast(&ipv6_daddr)) {
 466                 lowpan_cb(skb)->chan = NULL;
 467         } else {
 468                 u8 addr_type;
 469
 470                 /* Get destination BT device from skb.
 471                  * If there is no such peer then discard the packet.
 472                  */
 473                 convert_dest_bdaddr(&ipv6_daddr, &addr, &addr_type);
 474
 475                 BT_DBG("dest addr %pMR type %d IP %pI6c", &addr,
 476                        addr_type, &ipv6_daddr);
 477
 478                 peer = peer_lookup_ba(dev, &addr, addr_type);
 479                 if (!peer) {
 480                         /* The packet might be sent to 6lowpan interface
 481                          * because of routing (either via default route
 482                          * or user set route) so get peer according to
 483                          * the destination address.
 484                          */
 485                         peer = peer_lookup_dst(dev, &ipv6_daddr, skb);
 486                         if (!peer) {
 487                                 BT_DBG("no such peer %pMR found", &addr);
 488                                 return -ENOENT;
 489                         }
 490                 }
 491
 492                 daddr = peer->eui64_addr;
 493                 *peer_addr = addr;
 494                 *peer_addr_type = addr_type;
 495                 lowpan_cb(skb)->chan = peer->chan;
 496
 497                 status = 1;
 498         }
 499
 500         lowpan_header_compress(skb, netdev, ETH_P_IPV6, daddr,
 501                                dev->netdev->dev_addr, skb->len);
 502
 503         err = dev_hard_header(skb, netdev, ETH_P_IPV6, NULL, NULL, 0);
 504         if (err < 0)
 505                 return err;
 506
 507         return status;
 508 }
 509
 510 static int header_create(struct sk_buff *skb, struct net_device *netdev,
 511                          unsigned short type, const void *_daddr,
 512                          const void *_saddr, unsigned int len)
 513 {
 514         struct ipv6hdr *hdr;
 515
 516         if (type != ETH_P_IPV6)
 517                 return -EINVAL;
 518
 519         hdr = ipv6_hdr(skb);
 520
 521         memcpy(&lowpan_cb(skb)->addr, &hdr->daddr, sizeof(struct in6_addr));
 522
 523         return 0;
 524 }
 525
 526 /* Packet to BT LE device */
 527 static int send_pkt(struct l2cap_chan *chan, struct sk_buff *skb,
 528                     struct net_device *netdev)
 529 {
 530         struct msghdr msg;
 531         struct kvec iv;
 532         int err;
 533
 534         /* Remember the skb so that we can send EAGAIN to the caller if
 535          * we run out of credits.
 536          */
 537         chan->data = skb;
 538
 539         iv.iov_base = skb->data;
 540         iv.iov_len = skb->len;
 541
 542         memset(&msg, 0, sizeof(msg));
 543         iov_iter_kvec(&msg.msg_iter, WRITE | ITER_KVEC, &iv, 1, skb->len);
 544
 545         err = l2cap_chan_send(chan, &msg, skb->len);
 546         if (err > 0) {
 547                 netdev->stats.tx_bytes += err;
 548                 netdev->stats.tx_packets++;
 549                 return 0;
 550         }
 551
 552         if (!err)
 553                 err = lowpan_cb(skb)->status;
 554
 555         if (err < 0) {
 556                 if (err == -EAGAIN)
 557                         netdev->stats.tx_dropped++;
 558                 else
 559                         netdev->stats.tx_errors++;
 560         }
 561
 562         return err;
 563 }
 564
 565 static int send_mcast_pkt(struct sk_buff *skb, struct net_device *netdev)
 566 {
 567         struct sk_buff *local_skb;
 568         struct lowpan_dev *entry;
 569         int err = 0;
 570
 571         rcu_read_lock();
 572
 573         list_for_each_entry_rcu(entry, &bt_6lowpan_devices, list) {
 574                 struct lowpan_peer *pentry;
 575                 struct lowpan_dev *dev;
 576
 577                 if (entry->netdev != netdev)
 578                         continue;
 579
 580                 dev = lowpan_dev(entry->netdev);
 581
 582                 list_for_each_entry_rcu(pentry, &dev->peers, list) {
 583                         int ret;
 584
 585                         local_skb = skb_clone(skb, GFP_ATOMIC);
 586
 587                         BT_DBG("xmit %s to %pMR type %d IP %pI6c chan %p",
 588                                netdev->name,
 589                                &pentry->chan->dst, pentry->chan->dst_type,
 590                                &pentry->peer_addr, pentry->chan);
 591                         ret = send_pkt(pentry->chan, local_skb, netdev);
 592                         if (ret < 0)
 593                                 err = ret;
 594
 595                         kfree_skb(local_skb);
 596                 }
 597         }
 598
 599         rcu_read_unlock();
 600
 601         return err;
 602 }
 603
 604 static netdev_tx_t bt_xmit(struct sk_buff *skb, struct net_device *netdev)
 605 {
 606         int err = 0;
 607         bdaddr_t addr;
 608         u8 addr_type;
 609
 610         /* We must take a copy of the skb before we modify/replace the ipv6
 611          * header as the header could be used elsewhere
 612          */
 613         skb = skb_unshare(skb, GFP_ATOMIC);
 614         if (!skb)
 615                 return NET_XMIT_DROP;
 616
 617         /* Return values from setup_header()
 618          *  <0 - error, packet is dropped
 619          *   0 - this is a multicast packet
 620          *   1 - this is unicast packet
 621          */
 622         err = setup_header(skb, netdev, &addr, &addr_type);
 623         if (err < 0) {
 624                 kfree_skb(skb);
 625                 return NET_XMIT_DROP;
 626         }
 627
 628         if (err) {
 629                 if (lowpan_cb(skb)->chan) {
 630                         BT_DBG("xmit %s to %pMR type %d IP %pI6c chan %p",
 631                                netdev->name, &addr, addr_type,
 632                                &lowpan_cb(skb)->addr, lowpan_cb(skb)->chan);
 633                         err = send_pkt(lowpan_cb(skb)->chan, skb, netdev);
 634                 } else {
 635                         err = -ENOENT;
 636                 }
 637         } else {
 638                 /* We need to send the packet to every device behind this
 639                  * interface.
 640                  */
 641                 err = send_mcast_pkt(skb, netdev);
 642         }
 643
 644         dev_kfree_skb(skb);
 645
 646         if (err)
 647                 BT_DBG("ERROR: xmit failed (%d)", err);
 648
 649         return err < 0 ? NET_XMIT_DROP : err;
 650 }
 651
 652 static struct lock_class_key bt_tx_busylock;
 653 static struct lock_class_key bt_netdev_xmit_lock_key;
 654
 655 static void bt_set_lockdep_class_one(struct net_device *dev,
 656                                      struct netdev_queue *txq,
 657                                      void *_unused)
 658 {
 659         lockdep_set_class(&txq->_xmit_lock, &bt_netdev_xmit_lock_key);
 660 }
 661
 662 static int bt_dev_init(struct net_device *dev)
 663 {
 664         netdev_for_each_tx_queue(dev, bt_set_lockdep_class_one, NULL);
 665         dev->qdisc_tx_busylock = &bt_tx_busylock;
 666
 667         return 0;
 668 }
 669
 670 static const struct net_device_ops netdev_ops = {
 671         .ndo_init               = bt_dev_init,
 672         .ndo_start_xmit         = bt_xmit,
 673 };
 674
 675 static struct header_ops header_ops = {
 676         .create = header_create,
 677 };
 678
 679 static void netdev_setup(struct net_device *dev)
 680 {
 681         dev->addr_len           = EUI64_ADDR_LEN;
 682         dev->type               = ARPHRD_6LOWPAN;
 683
 684         dev->hard_header_len    = 0;
 685         dev->needed_tailroom    = 0;
 686         dev->mtu                = IPV6_MIN_MTU;
 687         dev->tx_queue_len       = 0;
 688         dev->flags              = IFF_RUNNING | IFF_POINTOPOINT |
 689                                   IFF_MULTICAST;
 690         dev->watchdog_timeo     = 0;
 691
 692         dev->netdev_ops         = &netdev_ops;
 693         dev->header_ops         = &header_ops;
 694         dev->destructor         = free_netdev;
 695 }
 696
 697 static struct device_type bt_type = {
 698         .name   = "bluetooth",
 699 };
 700
 701 static void set_addr(u8 *eui, u8 *addr, u8 addr_type)
 702 {
 703         /* addr is the BT address in little-endian format */
 704         eui[0] = addr[5];
 705         eui[1] = addr[4];
 706         eui[2] = addr[3];
 707         eui[3] = 0xFF;
 708         eui[4] = 0xFE;
 709         eui[5] = addr[2];
 710         eui[6] = addr[1];
 711         eui[7] = addr[0];
 712
 713         /* Universal/local bit set, BT 6lowpan draft ch. 3.2.1 */
 714         if (addr_type == BDADDR_LE_PUBLIC)
 715                 eui[0] &= ~0x02;
 716         else
 717                 eui[0] |= 0x02;
 718
 719         BT_DBG("type %d addr %*phC", addr_type, 8, eui);
 720 }
 721
 722 static void set_dev_addr(struct net_device *netdev, bdaddr_t *addr,
 723                          u8 addr_type)
 724 {
 725         netdev->addr_assign_type = NET_ADDR_PERM;
 726         set_addr(netdev->dev_addr, addr->b, addr_type);
 727 }
 728
 729 static void ifup(struct net_device *netdev)
 730 {
 731         int err;
 732
 733         rtnl_lock();
 734         err = dev_open(netdev);
 735         if (err < 0)
 736                 BT_INFO("iface %s cannot be opened (%d)", netdev->name, err);
 737         rtnl_unlock();
 738 }
 739
 740 static void ifdown(struct net_device *netdev)
 741 {
 742         int err;
 743
 744         rtnl_lock();
 745         err = dev_close(netdev);
 746         if (err < 0)
 747                 BT_INFO("iface %s cannot be closed (%d)", netdev->name, err);
 748         rtnl_unlock();
 749 }
 750
 751 static void do_notify_peers(struct work_struct *work)
 752 {
 753         struct lowpan_dev *dev = container_of(work, struct lowpan_dev,
 754                                               notify_peers.work);
 755
 756         netdev_notify_peers(dev->netdev); /* send neighbour adv at startup */
 757 }
 758
 759 static bool is_bt_6lowpan(struct hci_conn *hcon)
 760 {
 761         if (hcon->type != LE_LINK)
 762                 return false;
 763
 764         if (!psm_6lowpan)
 765                 return false;
 766
 767         return true;
 768 }
 769
 770 static struct l2cap_chan *chan_create(void)
 771 {
 772         struct l2cap_chan *chan;
 773
 774         chan = l2cap_chan_create();
 775         if (!chan)
 776                 return NULL;
 777
 778         l2cap_chan_set_defaults(chan);
 779
 780         chan->chan_type = L2CAP_CHAN_CONN_ORIENTED;
 781         chan->mode = L2CAP_MODE_LE_FLOWCTL;
 782         chan->omtu = 65535;
 783         chan->imtu = chan->omtu;
 784
 785         return chan;
 786 }
 787
 788 static struct l2cap_chan *chan_open(struct l2cap_chan *pchan)
 789 {
 790         struct l2cap_chan *chan;
 791
 792         chan = chan_create();
 793         if (!chan)
 794                 return NULL;
 795
 796         chan->remote_mps = chan->omtu;
 797         chan->mps = chan->omtu;
 798
 799         chan->state = BT_CONNECTED;
 800
 801         return chan;
 802 }
 803
 804 static void set_ip_addr_bits(u8 addr_type, u8 *addr)
 805 {
 806         if (addr_type == BDADDR_LE_PUBLIC)
 807                 *addr |= 0x02;
 808         else
 809                 *addr &= ~0x02;
 810 }
 811
 812 static struct l2cap_chan *add_peer_chan(struct l2cap_chan *chan,
 813                                         struct lowpan_dev *dev)
 814 {
 815         struct lowpan_peer *peer;
 816
 817         peer = kzalloc(sizeof(*peer), GFP_ATOMIC);
 818         if (!peer)
 819                 return NULL;
 820
 821         peer->chan = chan;
 822         memset(&peer->peer_addr, 0, sizeof(struct in6_addr));
 823
 824         /* RFC 2464 ch. 5 */
 825         peer->peer_addr.s6_addr[0] = 0xFE;
 826         peer->peer_addr.s6_addr[1] = 0x80;
 827         set_addr((u8 *)&peer->peer_addr.s6_addr + 8, chan->dst.b,
 828                  chan->dst_type);
 829
 830         memcpy(&peer->eui64_addr, (u8 *)&peer->peer_addr.s6_addr + 8,
 831                EUI64_ADDR_LEN);
 832
 833         /* IPv6 address needs to have the U/L bit set properly so toggle
 834          * it back here.
 835          */
 836         set_ip_addr_bits(chan->dst_type, (u8 *)&peer->peer_addr.s6_addr + 8);
 837
 838         spin_lock(&devices_lock);
 839         INIT_LIST_HEAD(&peer->list);
 840         peer_add(dev, peer);
 841         spin_unlock(&devices_lock);
 842
 843         /* Notifying peers about us needs to be done without locks held */
 844         INIT_DELAYED_WORK(&dev->notify_peers, do_notify_peers);
 845         schedule_delayed_work(&dev->notify_peers, msecs_to_jiffies(100));
 846
 847         return peer->chan;
 848 }
 849
 850 static int setup_netdev(struct l2cap_chan *chan, struct lowpan_dev **dev)
 851 {
 852         struct net_device *netdev;
 853         int err = 0;
 854
 855         netdev = alloc_netdev(sizeof(struct lowpan_dev), IFACE_NAME_TEMPLATE,
 856                               NET_NAME_UNKNOWN, netdev_setup);
 857         if (!netdev)
 858                 return -ENOMEM;
 859
 860         set_dev_addr(netdev, &chan->src, chan->src_type);
 861
 862         netdev->netdev_ops = &netdev_ops;
 863         SET_NETDEV_DEV(netdev, &chan->conn->hcon->dev);
 864         SET_NETDEV_DEVTYPE(netdev, &bt_type);
 865
 866         err = register_netdev(netdev);
 867         if (err < 0) {
 868                 BT_INFO("register_netdev failed %d", err);
 869                 free_netdev(netdev);
 870                 goto out;
 871         }
 872
 873         BT_DBG("ifindex %d peer bdaddr %pMR type %d my addr %pMR type %d",
 874                netdev->ifindex, &chan->dst, chan->dst_type,
 875                &chan->src, chan->src_type);
 876         set_bit(__LINK_STATE_PRESENT, &netdev->state);
 877
 878         *dev = netdev_priv(netdev);
 879         (*dev)->netdev = netdev;
 880         (*dev)->hdev = chan->conn->hcon->hdev;
 881         INIT_LIST_HEAD(&(*dev)->peers);
 882
 883         spin_lock(&devices_lock);
 884         INIT_LIST_HEAD(&(*dev)->list);
 885         list_add_rcu(&(*dev)->list, &bt_6lowpan_devices);
 886         spin_unlock(&devices_lock);
 887
 888         return 0;
 889
 890 out:
 891         return err;
 892 }
 893
 894 static inline void chan_ready_cb(struct l2cap_chan *chan)
 895 {
 896         struct lowpan_dev *dev;
 897
 898         dev = lookup_dev(chan->conn);
 899
 900         BT_DBG("chan %p conn %p dev %p", chan, chan->conn, dev);
 901
 902         if (!dev) {
 903                 if (setup_netdev(chan, &dev) < 0) {
 904                         l2cap_chan_del(chan, -ENOENT);
 905                         return;
 906                 }
 907         }
 908
 909         if (!try_module_get(THIS_MODULE))
 910                 return;
 911
 912         add_peer_chan(chan, dev);
 913         ifup(dev->netdev);
 914 }
 915
 916 static inline struct l2cap_chan *chan_new_conn_cb(struct l2cap_chan *pchan)
 917 {
 918         struct l2cap_chan *chan;
 919
 920         chan = chan_open(pchan);
 921         chan->ops = pchan->ops;
 922
 923         BT_DBG("chan %p pchan %p", chan, pchan);
 924
 925         return chan;
 926 }
 927
 928 static void delete_netdev(struct work_struct *work)
 929 {
 930         struct lowpan_dev *entry = container_of(work, struct lowpan_dev,
 931                                                 delete_netdev);
 932
 933         unregister_netdev(entry->netdev);
 934
 935         /* The entry pointer is deleted in device_event() */
 936 }
 937
 938 static void chan_close_cb(struct l2cap_chan *chan)
 939 {
 940         struct lowpan_dev *entry;
 941         struct lowpan_dev *dev = NULL;
 942         struct lowpan_peer *peer;
 943         int err = -ENOENT;
 944         bool last = false, removed = true;
 945
 946         BT_DBG("chan %p conn %p", chan, chan->conn);
 947
 948         if (chan->conn && chan->conn->hcon) {
 949                 if (!is_bt_6lowpan(chan->conn->hcon))
 950                         return;
 951
 952                 /* If conn is set, then the netdev is also there and we should
 953                  * not remove it.
 954                  */
 955                 removed = false;
 956         }
 957
 958         spin_lock(&devices_lock);
 959
 960         list_for_each_entry_rcu(entry, &bt_6lowpan_devices, list) {
 961                 dev = lowpan_dev(entry->netdev);
 962                 peer = __peer_lookup_chan(dev, chan);
 963                 if (peer) {
 964                         last = peer_del(dev, peer);
 965                         err = 0;
 966
 967                         BT_DBG("dev %p removing %speer %p", dev,
 968                                last ? "last " : "1 ", peer);
 969                         BT_DBG("chan %p orig refcnt %d", chan,
 970                                atomic_read(&chan->kref.refcount));
 971
 972                         l2cap_chan_put(chan);
 973                         break;
 974                 }
 975         }
 976
 977         if (!err && last && dev && !atomic_read(&dev->peer_count)) {
 978                 spin_unlock(&devices_lock);
 979
 980                 cancel_delayed_work_sync(&dev->notify_peers);
 981
 982                 ifdown(dev->netdev);
 983
 984                 if (!removed) {
 985                         INIT_WORK(&entry->delete_netdev, delete_netdev);
 986                         schedule_work(&entry->delete_netdev);
 987                 }
 988         } else {
 989                 spin_unlock(&devices_lock);
 990         }
 991
 992         return;
 993 }
 994
 995 static void chan_state_change_cb(struct l2cap_chan *chan, int state, int err)
 996 {
 997         BT_DBG("chan %p conn %p state %s err %d", chan, chan->conn,
 998                state_to_string(state), err);
 999 }
1000
1001 static struct sk_buff *chan_alloc_skb_cb(struct l2cap_chan *chan,
1002                                          unsigned long hdr_len,
1003                                          unsigned long len, int nb)
1004 {
1005         /* Note that we must allocate using GFP_ATOMIC here as
1006          * this function is called originally from netdev hard xmit
1007          * function in atomic context.
1008          */
1009         return bt_skb_alloc(hdr_len + len, GFP_ATOMIC);
1010 }
1011
1012 static void chan_suspend_cb(struct l2cap_chan *chan)
1013 {
1014         struct sk_buff *skb = chan->data;
1015
1016         BT_DBG("chan %p conn %p skb %p", chan, chan->conn, skb);
1017
1018         if (!skb)
1019                 return;
1020
1021         lowpan_cb(skb)->status = -EAGAIN;
1022 }
1023
1024 static void chan_resume_cb(struct l2cap_chan *chan)
1025 {
1026         struct sk_buff *skb = chan->data;
1027
1028         BT_DBG("chan %p conn %p skb %p", chan, chan->conn, skb);
1029
1030         if (!skb)
1031                 return;
1032
1033         lowpan_cb(skb)->status = 0;
1034 }
1035
1036 static long chan_get_sndtimeo_cb(struct l2cap_chan *chan)
1037 {
1038         return L2CAP_CONN_TIMEOUT;
1039 }
1040
1041 static const struct l2cap_ops bt_6lowpan_chan_ops = {
1042         .name                   = "L2CAP 6LoWPAN channel",
1043         .new_connection         = chan_new_conn_cb,
1044         .recv                   = chan_recv_cb,
1045         .close                  = chan_close_cb,
1046         .state_change           = chan_state_change_cb,
1047         .ready                  = chan_ready_cb,
1048         .resume                 = chan_resume_cb,
1049         .suspend                = chan_suspend_cb,
1050         .get_sndtimeo           = chan_get_sndtimeo_cb,
1051         .alloc_skb              = chan_alloc_skb_cb,
1052
1053         .teardown               = l2cap_chan_no_teardown,
1054         .defer                  = l2cap_chan_no_defer,
1055         .set_shutdown           = l2cap_chan_no_set_shutdown,
1056 };
1057
1058 static inline __u8 bdaddr_type(__u8 type)
1059 {
1060         if (type == ADDR_LE_DEV_PUBLIC)
1061                 return BDADDR_LE_PUBLIC;
1062         else
1063                 return BDADDR_LE_RANDOM;
1064 }
1065
1066 static struct l2cap_chan *chan_get(void)
1067 {
1068         struct l2cap_chan *pchan;
1069
1070         pchan = chan_create();
1071         if (!pchan)
1072                 return NULL;
1073
1074         pchan->ops = &bt_6lowpan_chan_ops;
1075
1076         return pchan;
1077 }
1078
1079 static int bt_6lowpan_connect(bdaddr_t *addr, u8 dst_type)
1080 {
1081         struct l2cap_chan *pchan;
1082         int err;
1083
1084         pchan = chan_get();
1085         if (!pchan)
1086                 return -EINVAL;
1087
1088         err = l2cap_chan_connect(pchan, cpu_to_le16(psm_6lowpan), 0,
1089                                  addr, dst_type);
1090
1091         BT_DBG("chan %p err %d", pchan, err);
1092         if (err < 0)
1093                 l2cap_chan_put(pchan);
1094
1095         return err;
1096 }
1097
1098 static int bt_6lowpan_disconnect(struct l2cap_conn *conn, u8 dst_type)
1099 {
1100         struct lowpan_peer *peer;
1101
1102         BT_DBG("conn %p dst type %d", conn, dst_type);
1103
1104         peer = lookup_peer(conn);
1105         if (!peer)
1106                 return -ENOENT;
1107
1108         BT_DBG("peer %p chan %p", peer, peer->chan);
1109
1110         l2cap_chan_close(peer->chan, ENOENT);
1111
1112         return 0;
1113 }
1114
1115 static struct l2cap_chan *bt_6lowpan_listen(void)
1116 {
1117         bdaddr_t *addr = BDADDR_ANY;
1118         struct l2cap_chan *pchan;
1119         int err;
1120
1121         if (psm_6lowpan == 0)
1122                 return NULL;
1123
1124         pchan = chan_get();
1125         if (!pchan)
1126                 return NULL;
1127
1128         pchan->state = BT_LISTEN;
1129         pchan->src_type = BDADDR_LE_PUBLIC;
1130
1131         atomic_set(&pchan->nesting, L2CAP_NESTING_PARENT);
1132
1133         BT_DBG("psm 0x%04x chan %p src type %d", psm_6lowpan, pchan,
1134                pchan->src_type);
1135
1136         err = l2cap_add_psm(pchan, addr, cpu_to_le16(psm_6lowpan));
1137         if (err) {
1138                 l2cap_chan_put(pchan);
1139                 BT_ERR("psm cannot be added err %d", err);
1140                 return NULL;
1141         }
1142
1143         return pchan;
1144 }
1145
1146 static int get_l2cap_conn(char *buf, bdaddr_t *addr, u8 *addr_type,
1147                           struct l2cap_conn **conn)
1148 {
1149         struct hci_conn *hcon;
1150         struct hci_dev *hdev;
1151         bdaddr_t *src = BDADDR_ANY;
1152         int n;
1153
1154         n = sscanf(buf, "%hhx:%hhx:%hhx:%hhx:%hhx:%hhx %hhu",
1155                    &addr->b[5], &addr->b[4], &addr->b[3],
1156                    &addr->b[2], &addr->b[1], &addr->b[0],
1157                    addr_type);
1158
1159         if (n < 7)
1160                 return -EINVAL;
1161
1162         hdev = hci_get_route(addr, src);
1163         if (!hdev)
1164                 return -ENOENT;
1165
1166         hci_dev_lock(hdev);
1167         hcon = hci_conn_hash_lookup_ba(hdev, LE_LINK, addr);
1168         hci_dev_unlock(hdev);
1169
1170         if (!hcon)
1171                 return -ENOENT;
1172
1173         *conn = (struct l2cap_conn *)hcon->l2cap_data;
1174
1175         BT_DBG("conn %p dst %pMR type %d", *conn, &hcon->dst, hcon->dst_type);
1176
1177         return 0;
1178 }
1179
1180 static void disconnect_all_peers(void)
1181 {
1182         struct lowpan_dev *entry;
1183         struct lowpan_peer *peer, *tmp_peer, *new_peer;
1184         struct list_head peers;
1185
1186         INIT_LIST_HEAD(&peers);
1187
1188         /* We make a separate list of peers as the close_cb() will
1189          * modify the device peers list so it is better not to mess
1190          * with the same list at the same time.
1191          */
1192
1193         rcu_read_lock();
1194
1195         list_for_each_entry_rcu(entry, &bt_6lowpan_devices, list) {
1196                 list_for_each_entry_rcu(peer, &entry->peers, list) {
1197                         new_peer = kmalloc(sizeof(*new_peer), GFP_ATOMIC);
1198                         if (!new_peer)
1199                                 break;
1200
1201                         new_peer->chan = peer->chan;
1202                         INIT_LIST_HEAD(&new_peer->list);
1203
1204                         list_add(&new_peer->list, &peers);
1205                 }
1206         }
1207
1208         rcu_read_unlock();
1209
1210         spin_lock(&devices_lock);
1211         list_for_each_entry_safe(peer, tmp_peer, &peers, list) {
1212                 l2cap_chan_close(peer->chan, ENOENT);
1213
1214                 list_del_rcu(&peer->list);
1215                 kfree_rcu(peer, rcu);
1216
1217                 module_put(THIS_MODULE);
1218         }
1219         spin_unlock(&devices_lock);
1220 }
1221
1222 struct set_psm {
1223         struct work_struct work;
1224         u16 psm;
1225 };
1226
1227 static void do_psm_set(struct work_struct *work)
1228 {
1229         struct set_psm *set_psm = container_of(work, struct set_psm, work);
1230
1231         if (set_psm->psm == 0 || psm_6lowpan != set_psm->psm)
1232                 /* Disconnect existing connections if 6lowpan is
1233                  * disabled (psm = 0), or if psm changes.
1234                  */
1235                 disconnect_all_peers();
1236
1237         psm_6lowpan = set_psm->psm;
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_psm);
1247 }
1248
1249 static int lowpan_psm_set(void *data, u64 val)
1250 {
1251         struct set_psm *set_psm;
1252
1253         set_psm = kzalloc(sizeof(*set_psm), GFP_KERNEL);
1254         if (!set_psm)
1255                 return -ENOMEM;
1256
1257         set_psm->psm = val;
1258         INIT_WORK(&set_psm->work, do_psm_set);
1259
1260         schedule_work(&set_psm->work);
1261
1262         return 0;
1263 }
1264
1265 static int lowpan_psm_get(void *data, u64 *val)
1266 {
1267         *val = psm_6lowpan;
1268         return 0;
1269 }
1270
1271 DEFINE_SIMPLE_ATTRIBUTE(lowpan_psm_fops, lowpan_psm_get,
1272                         lowpan_psm_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                                 kfree(entry);
1426                                 break;
1427                         }
1428                 }
1429                 spin_unlock(&devices_lock);
1430                 break;
1431         }
1432
1433         return NOTIFY_DONE;
1434 }
1435
1436 static struct notifier_block bt_6lowpan_dev_notifier = {
1437         .notifier_call = device_event,
1438 };
1439
1440 static int __init bt_6lowpan_init(void)
1441 {
1442         lowpan_psm_debugfs = debugfs_create_file("6lowpan_psm", 0644,
1443                                                  bt_debugfs, NULL,
1444                                                  &lowpan_psm_fops);
1445         lowpan_control_debugfs = debugfs_create_file("6lowpan_control", 0644,
1446                                                      bt_debugfs, NULL,
1447                                                      &lowpan_control_fops);
1448
1449         return register_netdevice_notifier(&bt_6lowpan_dev_notifier);
1450 }
1451
1452 static void __exit bt_6lowpan_exit(void)
1453 {
1454         debugfs_remove(lowpan_psm_debugfs);
1455         debugfs_remove(lowpan_control_debugfs);
1456
1457         if (listen_chan) {
1458                 l2cap_chan_close(listen_chan, 0);
1459                 l2cap_chan_put(listen_chan);
1460         }
1461
1462         disconnect_devices();
1463
1464         unregister_netdevice_notifier(&bt_6lowpan_dev_notifier);
1465 }
1466
1467 module_init(bt_6lowpan_init);
1468 module_exit(bt_6lowpan_exit);
1469
1470 MODULE_AUTHOR("Jukka Rissanen <jukka.rissanen@linux.intel.com>");
1471 MODULE_DESCRIPTION("Bluetooth 6LoWPAN");
1472 MODULE_VERSION(VERSION);
1473 MODULE_LICENSE("GPL");