net/ieee802154/6lowpan_rtnl.c

   1 /* Copyright 2011, Siemens AG
   2  * written by Alexander Smirnov <alex.bluesman.smirnov@gmail.com>
   3  */
   4
   5 /* Based on patches from Jon Smirl <jonsmirl@gmail.com>
   6  * Copyright (c) 2011 Jon Smirl <jonsmirl@gmail.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2
  10  * as published by the Free Software Foundation.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  */
  17
  18 /* Jon's code is based on 6lowpan implementation for Contiki which is:
  19  * Copyright (c) 2008, Swedish Institute of Computer Science.
  20  * All rights reserved.
  21  *
  22  * Redistribution and use in source and binary forms, with or without
  23  * modification, are permitted provided that the following conditions
  24  * are met:
  25  * 1. Redistributions of source code must retain the above copyright
  26  *    notice, this list of conditions and the following disclaimer.
  27  * 2. Redistributions in binary form must reproduce the above copyright
  28  *    notice, this list of conditions and the following disclaimer in the
  29  *    documentation and/or other materials provided with the distribution.
  30  * 3. Neither the name of the Institute nor the names of its contributors
  31  *    may be used to endorse or promote products derived from this software
  32  *    without specific prior written permission.
  33  *
  34  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
  35  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  36  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  37  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
  38  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  39  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  40  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  41  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  42  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  43  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  44  * SUCH DAMAGE.
  45  */
  46
  47 #include <linux/bitops.h>
  48 #include <linux/if_arp.h>
  49 #include <linux/module.h>
  50 #include <linux/moduleparam.h>
  51 #include <linux/netdevice.h>
  52 #include <linux/ieee802154.h>
  53 #include <net/af_ieee802154.h>
  54 #include <net/ieee802154_netdev.h>
  55 #include <net/6lowpan.h>
  56 #include <net/ipv6.h>
  57
  58 #include "reassembly.h"
  59
  60 static LIST_HEAD(lowpan_devices);
  61 static int lowpan_open_count;
  62
  63 /* private device info */
  64 struct lowpan_dev_info {
  65         struct net_device       *real_dev; /* real WPAN device ptr */
  66         struct mutex            dev_list_mtx; /* mutex for list ops */
  67         u16                     fragment_tag;
  68 };
  69
  70 struct lowpan_dev_record {
  71         struct net_device *ldev;
  72         struct list_head list;
  73 };
  74
  75 /* don't save pan id, it's intra pan */
  76 struct lowpan_addr {
  77         u8 mode;
  78         union {
  79                 /* IPv6 needs big endian here */
  80                 __be64 extended_addr;
  81                 __be16 short_addr;
  82         } u;
  83 };
  84
  85 struct lowpan_addr_info {
  86         struct lowpan_addr daddr;
  87         struct lowpan_addr saddr;
  88 };
  89
  90 static inline struct
  91 lowpan_dev_info *lowpan_dev_info(const struct net_device *dev)
  92 {
  93         return netdev_priv(dev);
  94 }
  95
  96 static inline struct
  97 lowpan_addr_info *lowpan_skb_priv(const struct sk_buff *skb)
  98 {
  99         WARN_ON_ONCE(skb_headroom(skb) < sizeof(struct lowpan_addr_info));
 100         return (struct lowpan_addr_info *)(skb->data -
 101                         sizeof(struct lowpan_addr_info));
 102 }
 103
 104 static int lowpan_header_create(struct sk_buff *skb, struct net_device *dev,
 105                                 unsigned short type, const void *_daddr,
 106                                 const void *_saddr, unsigned int len)
 107 {
 108         const u8 *saddr = _saddr;
 109         const u8 *daddr = _daddr;
 110         struct lowpan_addr_info *info;
 111
 112         /* TODO:
 113          * if this package isn't ipv6 one, where should it be routed?
 114          */
 115         if (type != ETH_P_IPV6)
 116                 return 0;
 117
 118         if (!saddr)
 119                 saddr = dev->dev_addr;
 120
 121         raw_dump_inline(__func__, "saddr", (unsigned char *)saddr, 8);
 122         raw_dump_inline(__func__, "daddr", (unsigned char *)daddr, 8);
 123
 124         info = lowpan_skb_priv(skb);
 125
 126         /* TODO: Currently we only support extended_addr */
 127         info->daddr.mode = IEEE802154_ADDR_LONG;
 128         memcpy(&info->daddr.u.extended_addr, daddr,
 129                sizeof(info->daddr.u.extended_addr));
 130         info->saddr.mode = IEEE802154_ADDR_LONG;
 131         memcpy(&info->saddr.u.extended_addr, saddr,
 132                sizeof(info->daddr.u.extended_addr));
 133
 134         return 0;
 135 }
 136
 137 static int lowpan_give_skb_to_devices(struct sk_buff *skb,
 138                                       struct net_device *dev)
 139 {
 140         struct lowpan_dev_record *entry;
 141         struct sk_buff *skb_cp;
 142         int stat = NET_RX_SUCCESS;
 143
 144         skb->protocol = htons(ETH_P_IPV6);
 145         skb->pkt_type = PACKET_HOST;
 146
 147         rcu_read_lock();
 148         list_for_each_entry_rcu(entry, &lowpan_devices, list)
 149                 if (lowpan_dev_info(entry->ldev)->real_dev == skb->dev) {
 150                         skb_cp = skb_copy(skb, GFP_ATOMIC);
 151                         if (!skb_cp) {
 152                                 kfree_skb(skb);
 153                                 rcu_read_unlock();
 154                                 return NET_RX_DROP;
 155                         }
 156
 157                         skb_cp->dev = entry->ldev;
 158                         stat = netif_rx(skb_cp);
 159                         if (stat == NET_RX_DROP)
 160                                 break;
 161                 }
 162         rcu_read_unlock();
 163
 164         consume_skb(skb);
 165
 166         return stat;
 167 }
 168
 169 static int
 170 iphc_decompress(struct sk_buff *skb, const struct ieee802154_hdr *hdr)
 171 {
 172         u8 iphc0, iphc1;
 173         struct ieee802154_addr_sa sa, da;
 174         void *sap, *dap;
 175
 176         raw_dump_table(__func__, "raw skb data dump", skb->data, skb->len);
 177         /* at least two bytes will be used for the encoding */
 178         if (skb->len < 2)
 179                 return -EINVAL;
 180
 181         if (lowpan_fetch_skb_u8(skb, &iphc0))
 182                 return -EINVAL;
 183
 184         if (lowpan_fetch_skb_u8(skb, &iphc1))
 185                 return -EINVAL;
 186
 187         ieee802154_addr_to_sa(&sa, &hdr->source);
 188         ieee802154_addr_to_sa(&da, &hdr->dest);
 189
 190         if (sa.addr_type == IEEE802154_ADDR_SHORT)
 191                 sap = &sa.short_addr;
 192         else
 193                 sap = &sa.hwaddr;
 194
 195         if (da.addr_type == IEEE802154_ADDR_SHORT)
 196                 dap = &da.short_addr;
 197         else
 198                 dap = &da.hwaddr;
 199
 200         return lowpan_header_decompress(skb, skb->dev, sap, sa.addr_type,
 201                                         IEEE802154_ADDR_LEN, dap, da.addr_type,
 202                                         IEEE802154_ADDR_LEN, iphc0, iphc1);
 203 }
 204
 205 static struct sk_buff*
 206 lowpan_alloc_frag(struct sk_buff *skb, int size,
 207                   const struct ieee802154_hdr *master_hdr)
 208 {
 209         struct net_device *real_dev = lowpan_dev_info(skb->dev)->real_dev;
 210         struct sk_buff *frag;
 211         int rc;
 212
 213         frag = alloc_skb(real_dev->hard_header_len +
 214                          real_dev->needed_tailroom + size,
 215                          GFP_ATOMIC);
 216
 217         if (likely(frag)) {
 218                 frag->dev = real_dev;
 219                 frag->priority = skb->priority;
 220                 skb_reserve(frag, real_dev->hard_header_len);
 221                 skb_reset_network_header(frag);
 222                 *mac_cb(frag) = *mac_cb(skb);
 223
 224                 rc = dev_hard_header(frag, real_dev, 0, &master_hdr->dest,
 225                                      &master_hdr->source, size);
 226                 if (rc < 0) {
 227                         kfree_skb(frag);
 228                         return ERR_PTR(rc);
 229                 }
 230         } else {
 231                 frag = ERR_PTR(-ENOMEM);
 232         }
 233
 234         return frag;
 235 }
 236
 237 static int
 238 lowpan_xmit_fragment(struct sk_buff *skb, const struct ieee802154_hdr *wpan_hdr,
 239                      u8 *frag_hdr, int frag_hdrlen,
 240                      int offset, int len)
 241 {
 242         struct sk_buff *frag;
 243
 244         raw_dump_inline(__func__, " fragment header", frag_hdr, frag_hdrlen);
 245
 246         frag = lowpan_alloc_frag(skb, frag_hdrlen + len, wpan_hdr);
 247         if (IS_ERR(frag))
 248                 return -PTR_ERR(frag);
 249
 250         memcpy(skb_put(frag, frag_hdrlen), frag_hdr, frag_hdrlen);
 251         memcpy(skb_put(frag, len), skb_network_header(skb) + offset, len);
 252
 253         raw_dump_table(__func__, " fragment dump", frag->data, frag->len);
 254
 255         return dev_queue_xmit(frag);
 256 }
 257
 258 static int
 259 lowpan_xmit_fragmented(struct sk_buff *skb, struct net_device *dev,
 260                        const struct ieee802154_hdr *wpan_hdr)
 261 {
 262         u16 dgram_size, dgram_offset;
 263         __be16 frag_tag;
 264         u8 frag_hdr[5];
 265         int frag_cap, frag_len, payload_cap, rc;
 266         int skb_unprocessed, skb_offset;
 267
 268         dgram_size = lowpan_uncompress_size(skb, &dgram_offset) -
 269                      skb->mac_len;
 270         frag_tag = htons(lowpan_dev_info(dev)->fragment_tag);
 271         lowpan_dev_info(dev)->fragment_tag++;
 272
 273         frag_hdr[0] = LOWPAN_DISPATCH_FRAG1 | ((dgram_size >> 8) & 0x07);
 274         frag_hdr[1] = dgram_size & 0xff;
 275         memcpy(frag_hdr + 2, &frag_tag, sizeof(frag_tag));
 276
 277         payload_cap = ieee802154_max_payload(wpan_hdr);
 278
 279         frag_len = round_down(payload_cap - LOWPAN_FRAG1_HEAD_SIZE -
 280                               skb_network_header_len(skb), 8);
 281
 282         skb_offset = skb_network_header_len(skb);
 283         skb_unprocessed = skb->len - skb->mac_len - skb_offset;
 284
 285         rc = lowpan_xmit_fragment(skb, wpan_hdr, frag_hdr,
 286                                   LOWPAN_FRAG1_HEAD_SIZE, 0,
 287                                   frag_len + skb_network_header_len(skb));
 288         if (rc) {
 289                 pr_debug("%s unable to send FRAG1 packet (tag: %d)",
 290                          __func__, ntohs(frag_tag));
 291                 goto err;
 292         }
 293
 294         frag_hdr[0] &= ~LOWPAN_DISPATCH_FRAG1;
 295         frag_hdr[0] |= LOWPAN_DISPATCH_FRAGN;
 296         frag_cap = round_down(payload_cap - LOWPAN_FRAGN_HEAD_SIZE, 8);
 297
 298         do {
 299                 dgram_offset += frag_len;
 300                 skb_offset += frag_len;
 301                 skb_unprocessed -= frag_len;
 302                 frag_len = min(frag_cap, skb_unprocessed);
 303
 304                 frag_hdr[4] = dgram_offset >> 3;
 305
 306                 rc = lowpan_xmit_fragment(skb, wpan_hdr, frag_hdr,
 307                                           LOWPAN_FRAGN_HEAD_SIZE, skb_offset,
 308                                           frag_len);
 309                 if (rc) {
 310                         pr_debug("%s unable to send a FRAGN packet. (tag: %d, offset: %d)\n",
 311                                  __func__, ntohs(frag_tag), skb_offset);
 312                         goto err;
 313                 }
 314         } while (skb_unprocessed > frag_cap);
 315
 316         consume_skb(skb);
 317         return NET_XMIT_SUCCESS;
 318
 319 err:
 320         kfree_skb(skb);
 321         return rc;
 322 }
 323
 324 static int lowpan_header(struct sk_buff *skb, struct net_device *dev)
 325 {
 326         struct ieee802154_addr sa, da;
 327         struct ieee802154_mac_cb *cb = mac_cb_init(skb);
 328         struct lowpan_addr_info info;
 329         void *daddr, *saddr;
 330
 331         memcpy(&info, lowpan_skb_priv(skb), sizeof(info));
 332
 333         /* TODO: Currently we only support extended_addr */
 334         daddr = &info.daddr.u.extended_addr;
 335         saddr = &info.saddr.u.extended_addr;
 336
 337         lowpan_header_compress(skb, dev, ETH_P_IPV6, daddr, saddr, skb->len);
 338
 339         cb->type = IEEE802154_FC_TYPE_DATA;
 340
 341         /* prepare wpan address data */
 342         sa.mode = IEEE802154_ADDR_LONG;
 343         sa.pan_id = ieee802154_mlme_ops(dev)->get_pan_id(dev);
 344         sa.extended_addr = ieee802154_devaddr_from_raw(saddr);
 345
 346         /* intra-PAN communications */
 347         da.pan_id = sa.pan_id;
 348
 349         /* if the destination address is the broadcast address, use the
 350          * corresponding short address
 351          */
 352         if (lowpan_is_addr_broadcast((const u8 *)daddr)) {
 353                 da.mode = IEEE802154_ADDR_SHORT;
 354                 da.short_addr = cpu_to_le16(IEEE802154_ADDR_BROADCAST);
 355                 cb->ackreq = false;
 356         } else {
 357                 da.mode = IEEE802154_ADDR_LONG;
 358                 da.extended_addr = ieee802154_devaddr_from_raw(daddr);
 359                 cb->ackreq = true;
 360         }
 361
 362         return dev_hard_header(skb, lowpan_dev_info(dev)->real_dev,
 363                         ETH_P_IPV6, (void *)&da, (void *)&sa, 0);
 364 }
 365
 366 static netdev_tx_t lowpan_xmit(struct sk_buff *skb, struct net_device *dev)
 367 {
 368         struct ieee802154_hdr wpan_hdr;
 369         int max_single, ret;
 370
 371         pr_debug("package xmit\n");
 372
 373         /* We must take a copy of the skb before we modify/replace the ipv6
 374          * header as the header could be used elsewhere
 375          */
 376         skb = skb_unshare(skb, GFP_ATOMIC);
 377         if (!skb)
 378                 return NET_XMIT_DROP;
 379
 380         ret = lowpan_header(skb, dev);
 381         if (ret < 0) {
 382                 kfree_skb(skb);
 383                 return NET_XMIT_DROP;
 384         }
 385
 386         if (ieee802154_hdr_peek(skb, &wpan_hdr) < 0) {
 387                 kfree_skb(skb);
 388                 return NET_XMIT_DROP;
 389         }
 390
 391         max_single = ieee802154_max_payload(&wpan_hdr);
 392
 393         if (skb_tail_pointer(skb) - skb_network_header(skb) <= max_single) {
 394                 skb->dev = lowpan_dev_info(dev)->real_dev;
 395                 return dev_queue_xmit(skb);
 396         } else {
 397                 netdev_tx_t rc;
 398
 399                 pr_debug("frame is too big, fragmentation is needed\n");
 400                 rc = lowpan_xmit_fragmented(skb, dev, &wpan_hdr);
 401
 402                 return rc < 0 ? NET_XMIT_DROP : rc;
 403         }
 404 }
 405
 406 static __le16 lowpan_get_pan_id(const struct net_device *dev)
 407 {
 408         struct net_device *real_dev = lowpan_dev_info(dev)->real_dev;
 409
 410         return ieee802154_mlme_ops(real_dev)->get_pan_id(real_dev);
 411 }
 412
 413 static __le16 lowpan_get_short_addr(const struct net_device *dev)
 414 {
 415         struct net_device *real_dev = lowpan_dev_info(dev)->real_dev;
 416
 417         return ieee802154_mlme_ops(real_dev)->get_short_addr(real_dev);
 418 }
 419
 420 static u8 lowpan_get_dsn(const struct net_device *dev)
 421 {
 422         struct net_device *real_dev = lowpan_dev_info(dev)->real_dev;
 423
 424         return ieee802154_mlme_ops(real_dev)->get_dsn(real_dev);
 425 }
 426
 427 static struct header_ops lowpan_header_ops = {
 428         .create = lowpan_header_create,
 429 };
 430
 431 static struct lock_class_key lowpan_tx_busylock;
 432 static struct lock_class_key lowpan_netdev_xmit_lock_key;
 433
 434 static void lowpan_set_lockdep_class_one(struct net_device *dev,
 435                                          struct netdev_queue *txq,
 436                                          void *_unused)
 437 {
 438         lockdep_set_class(&txq->_xmit_lock,
 439                           &lowpan_netdev_xmit_lock_key);
 440 }
 441
 442
 443 static int lowpan_dev_init(struct net_device *dev)
 444 {
 445         netdev_for_each_tx_queue(dev, lowpan_set_lockdep_class_one, NULL);
 446         dev->qdisc_tx_busylock = &lowpan_tx_busylock;
 447         return 0;
 448 }
 449
 450 static const struct net_device_ops lowpan_netdev_ops = {
 451         .ndo_init               = lowpan_dev_init,
 452         .ndo_start_xmit         = lowpan_xmit,
 453 };
 454
 455 static struct ieee802154_mlme_ops lowpan_mlme = {
 456         .get_pan_id = lowpan_get_pan_id,
 457         .get_short_addr = lowpan_get_short_addr,
 458         .get_dsn = lowpan_get_dsn,
 459 };
 460
 461 static void lowpan_setup(struct net_device *dev)
 462 {
 463         dev->addr_len           = IEEE802154_ADDR_LEN;
 464         memset(dev->broadcast, 0xff, IEEE802154_ADDR_LEN);
 465         dev->type               = ARPHRD_IEEE802154;
 466         /* Frame Control + Sequence Number + Address fields + Security Header */
 467         dev->hard_header_len    = 2 + 1 + 20 + 14;
 468         dev->needed_tailroom    = 2; /* FCS */
 469         dev->mtu                = IPV6_MIN_MTU;
 470         dev->tx_queue_len       = 0;
 471         dev->flags              = IFF_BROADCAST | IFF_MULTICAST;
 472         dev->watchdog_timeo     = 0;
 473
 474         dev->netdev_ops         = &lowpan_netdev_ops;
 475         dev->header_ops         = &lowpan_header_ops;
 476         dev->ml_priv            = &lowpan_mlme;
 477         dev->destructor         = free_netdev;
 478 }
 479
 480 static int lowpan_validate(struct nlattr *tb[], struct nlattr *data[])
 481 {
 482         if (tb[IFLA_ADDRESS]) {
 483                 if (nla_len(tb[IFLA_ADDRESS]) != IEEE802154_ADDR_LEN)
 484                         return -EINVAL;
 485         }
 486         return 0;
 487 }
 488
 489 static int lowpan_rcv(struct sk_buff *skb, struct net_device *dev,
 490                       struct packet_type *pt, struct net_device *orig_dev)
 491 {
 492         struct ieee802154_hdr hdr;
 493         int ret;
 494
 495         skb = skb_share_check(skb, GFP_ATOMIC);
 496         if (!skb)
 497                 goto drop;
 498
 499         if (!netif_running(dev))
 500                 goto drop_skb;
 501
 502         if (skb->pkt_type == PACKET_OTHERHOST)
 503                 goto drop_skb;
 504
 505         if (dev->type != ARPHRD_IEEE802154)
 506                 goto drop_skb;
 507
 508         if (ieee802154_hdr_peek_addrs(skb, &hdr) < 0)
 509                 goto drop_skb;
 510
 511         /* check that it's our buffer */
 512         if (skb->data[0] == LOWPAN_DISPATCH_IPV6) {
 513                 /* Pull off the 1-byte of 6lowpan header. */
 514                 skb_pull(skb, 1);
 515                 return lowpan_give_skb_to_devices(skb, NULL);
 516         } else {
 517                 switch (skb->data[0] & 0xe0) {
 518                 case LOWPAN_DISPATCH_IPHC:      /* ipv6 datagram */
 519                         ret = iphc_decompress(skb, &hdr);
 520                         if (ret < 0)
 521                                 goto drop_skb;
 522
 523                         return lowpan_give_skb_to_devices(skb, NULL);
 524                 case LOWPAN_DISPATCH_FRAG1:     /* first fragment header */
 525                         ret = lowpan_frag_rcv(skb, LOWPAN_DISPATCH_FRAG1);
 526                         if (ret == 1) {
 527                                 ret = iphc_decompress(skb, &hdr);
 528                                 if (ret < 0)
 529                                         goto drop_skb;
 530
 531                                 return lowpan_give_skb_to_devices(skb, NULL);
 532                         } else if (ret == -1) {
 533                                 return NET_RX_DROP;
 534                         } else {
 535                                 return NET_RX_SUCCESS;
 536                         }
 537                 case LOWPAN_DISPATCH_FRAGN:     /* next fragments headers */
 538                         ret = lowpan_frag_rcv(skb, LOWPAN_DISPATCH_FRAGN);
 539                         if (ret == 1) {
 540                                 ret = iphc_decompress(skb, &hdr);
 541                                 if (ret < 0)
 542                                         goto drop_skb;
 543
 544                                 return lowpan_give_skb_to_devices(skb, NULL);
 545                         } else if (ret == -1) {
 546                                 return NET_RX_DROP;
 547                         } else {
 548                                 return NET_RX_SUCCESS;
 549                         }
 550                 default:
 551                         break;
 552                 }
 553         }
 554
 555 drop_skb:
 556         kfree_skb(skb);
 557 drop:
 558         return NET_RX_DROP;
 559 }
 560
 561 static struct packet_type lowpan_packet_type = {
 562         .type = htons(ETH_P_IEEE802154),
 563         .func = lowpan_rcv,
 564 };
 565
 566 static int lowpan_newlink(struct net *src_net, struct net_device *dev,
 567                           struct nlattr *tb[], struct nlattr *data[])
 568 {
 569         struct net_device *real_dev;
 570         struct lowpan_dev_record *entry;
 571         int ret;
 572
 573         ASSERT_RTNL();
 574
 575         pr_debug("adding new link\n");
 576
 577         if (!tb[IFLA_LINK])
 578                 return -EINVAL;
 579         /* find and hold real wpan device */
 580         real_dev = dev_get_by_index(src_net, nla_get_u32(tb[IFLA_LINK]));
 581         if (!real_dev)
 582                 return -ENODEV;
 583         if (real_dev->type != ARPHRD_IEEE802154) {
 584                 dev_put(real_dev);
 585                 return -EINVAL;
 586         }
 587
 588         lowpan_dev_info(dev)->real_dev = real_dev;
 589         mutex_init(&lowpan_dev_info(dev)->dev_list_mtx);
 590
 591         entry = kzalloc(sizeof(*entry), GFP_KERNEL);
 592         if (!entry) {
 593                 dev_put(real_dev);
 594                 lowpan_dev_info(dev)->real_dev = NULL;
 595                 return -ENOMEM;
 596         }
 597
 598         entry->ldev = dev;
 599
 600         /* Set the lowpan harware address to the wpan hardware address. */
 601         memcpy(dev->dev_addr, real_dev->dev_addr, IEEE802154_ADDR_LEN);
 602
 603         mutex_lock(&lowpan_dev_info(dev)->dev_list_mtx);
 604         INIT_LIST_HEAD(&entry->list);
 605         list_add_tail(&entry->list, &lowpan_devices);
 606         mutex_unlock(&lowpan_dev_info(dev)->dev_list_mtx);
 607
 608         ret = register_netdevice(dev);
 609         if (ret >= 0) {
 610                 if (!lowpan_open_count)
 611                         dev_add_pack(&lowpan_packet_type);
 612                 lowpan_open_count++;
 613         }
 614
 615         return ret;
 616 }
 617
 618 static void lowpan_dellink(struct net_device *dev, struct list_head *head)
 619 {
 620         struct lowpan_dev_info *lowpan_dev = lowpan_dev_info(dev);
 621         struct net_device *real_dev = lowpan_dev->real_dev;
 622         struct lowpan_dev_record *entry, *tmp;
 623
 624         ASSERT_RTNL();
 625
 626         lowpan_open_count--;
 627         if (!lowpan_open_count)
 628                 dev_remove_pack(&lowpan_packet_type);
 629
 630         mutex_lock(&lowpan_dev_info(dev)->dev_list_mtx);
 631         list_for_each_entry_safe(entry, tmp, &lowpan_devices, list) {
 632                 if (entry->ldev == dev) {
 633                         list_del(&entry->list);
 634                         kfree(entry);
 635                 }
 636         }
 637         mutex_unlock(&lowpan_dev_info(dev)->dev_list_mtx);
 638
 639         mutex_destroy(&lowpan_dev_info(dev)->dev_list_mtx);
 640
 641         unregister_netdevice_queue(dev, head);
 642
 643         dev_put(real_dev);
 644 }
 645
 646 static struct rtnl_link_ops lowpan_link_ops __read_mostly = {
 647         .kind           = "lowpan",
 648         .priv_size      = sizeof(struct lowpan_dev_info),
 649         .setup          = lowpan_setup,
 650         .newlink        = lowpan_newlink,
 651         .dellink        = lowpan_dellink,
 652         .validate       = lowpan_validate,
 653 };
 654
 655 static inline int __init lowpan_netlink_init(void)
 656 {
 657         return rtnl_link_register(&lowpan_link_ops);
 658 }
 659
 660 static inline void lowpan_netlink_fini(void)
 661 {
 662         rtnl_link_unregister(&lowpan_link_ops);
 663 }
 664
 665 static int lowpan_device_event(struct notifier_block *unused,
 666                                unsigned long event, void *ptr)
 667 {
 668         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
 669         LIST_HEAD(del_list);
 670         struct lowpan_dev_record *entry, *tmp;
 671
 672         if (dev->type != ARPHRD_IEEE802154)
 673                 goto out;
 674
 675         if (event == NETDEV_UNREGISTER) {
 676                 list_for_each_entry_safe(entry, tmp, &lowpan_devices, list) {
 677                         if (lowpan_dev_info(entry->ldev)->real_dev == dev)
 678                                 lowpan_dellink(entry->ldev, &del_list);
 679                 }
 680
 681                 unregister_netdevice_many(&del_list);
 682         }
 683
 684 out:
 685         return NOTIFY_DONE;
 686 }
 687
 688 static struct notifier_block lowpan_dev_notifier = {
 689         .notifier_call = lowpan_device_event,
 690 };
 691
 692 static int __init lowpan_init_module(void)
 693 {
 694         int err = 0;
 695
 696         err = lowpan_net_frag_init();
 697         if (err < 0)
 698                 goto out;
 699
 700         err = lowpan_netlink_init();
 701         if (err < 0)
 702                 goto out_frag;
 703
 704         err = register_netdevice_notifier(&lowpan_dev_notifier);
 705         if (err < 0)
 706                 goto out_pack;
 707
 708         return 0;
 709
 710 out_pack:
 711         lowpan_netlink_fini();
 712 out_frag:
 713         lowpan_net_frag_exit();
 714 out:
 715         return err;
 716 }
 717
 718 static void __exit lowpan_cleanup_module(void)
 719 {
 720         lowpan_netlink_fini();
 721
 722         lowpan_net_frag_exit();
 723
 724         unregister_netdevice_notifier(&lowpan_dev_notifier);
 725 }
 726
 727 module_init(lowpan_init_module);
 728 module_exit(lowpan_cleanup_module);
 729 MODULE_LICENSE("GPL");
 730 MODULE_ALIAS_RTNL_LINK("lowpan");