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 <net/af_ieee802154.h>
  53 #include <net/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
  62 /* private device info */
  63 struct lowpan_dev_info {
  64         struct net_device       *real_dev; /* real WPAN device ptr */
  65         struct mutex            dev_list_mtx; /* mutex for list ops */
  66         __be16                  fragment_tag;
  67 };
  68
  69 struct lowpan_dev_record {
  70         struct net_device *ldev;
  71         struct list_head list;
  72 };
  73
  74 /* don't save pan id, it's intra pan */
  75 struct lowpan_addr {
  76         u8 mode;
  77         union {
  78                 /* IPv6 needs big endian here */
  79                 __be64 extended_addr;
  80                 __be16 short_addr;
  81         } u;
  82 };
  83
  84 struct lowpan_addr_info {
  85         struct lowpan_addr daddr;
  86         struct lowpan_addr saddr;
  87 };
  88
  89 static inline struct
  90 lowpan_dev_info *lowpan_dev_info(const struct net_device *dev)
  91 {
  92         return netdev_priv(dev);
  93 }
  94
  95 static inline struct
  96 lowpan_addr_info *lowpan_skb_priv(const struct sk_buff *skb)
  97 {
  98         WARN_ON_ONCE(skb_headroom(skb) < sizeof(struct lowpan_addr_info));
  99         return (struct lowpan_addr_info *)(skb->data -
 100                         sizeof(struct lowpan_addr_info));
 101 }
 102
 103 static int lowpan_header_create(struct sk_buff *skb, struct net_device *dev,
 104                                 unsigned short type, const void *_daddr,
 105                                 const void *_saddr, unsigned int len)
 106 {
 107         const u8 *saddr = _saddr;
 108         const u8 *daddr = _daddr;
 109         struct lowpan_addr_info *info;
 110
 111         /* TODO:
 112          * if this package isn't ipv6 one, where should it be routed?
 113          */
 114         if (type != ETH_P_IPV6)
 115                 return 0;
 116
 117         if (!saddr)
 118                 saddr = dev->dev_addr;
 119
 120         raw_dump_inline(__func__, "saddr", (unsigned char *)saddr, 8);
 121         raw_dump_inline(__func__, "daddr", (unsigned char *)daddr, 8);
 122
 123         info = lowpan_skb_priv(skb);
 124
 125         /* TODO: Currently we only support extended_addr */
 126         info->daddr.mode = IEEE802154_ADDR_LONG;
 127         memcpy(&info->daddr.u.extended_addr, daddr,
 128                sizeof(info->daddr.u.extended_addr));
 129         info->saddr.mode = IEEE802154_ADDR_LONG;
 130         memcpy(&info->saddr.u.extended_addr, saddr,
 131                sizeof(info->daddr.u.extended_addr));
 132
 133         return 0;
 134 }
 135
 136 static int lowpan_give_skb_to_devices(struct sk_buff *skb,
 137                                       struct net_device *dev)
 138 {
 139         struct lowpan_dev_record *entry;
 140         struct sk_buff *skb_cp;
 141         int stat = NET_RX_SUCCESS;
 142
 143         rcu_read_lock();
 144         list_for_each_entry_rcu(entry, &lowpan_devices, list)
 145                 if (lowpan_dev_info(entry->ldev)->real_dev == skb->dev) {
 146                         skb_cp = skb_copy(skb, GFP_ATOMIC);
 147                         if (!skb_cp) {
 148                                 stat = -ENOMEM;
 149                                 break;
 150                         }
 151
 152                         skb_cp->dev = entry->ldev;
 153                         stat = netif_rx(skb_cp);
 154                 }
 155         rcu_read_unlock();
 156
 157         return stat;
 158 }
 159
 160 static int process_data(struct sk_buff *skb, const struct ieee802154_hdr *hdr)
 161 {
 162         u8 iphc0, iphc1;
 163         struct ieee802154_addr_sa sa, da;
 164         void *sap, *dap;
 165
 166         raw_dump_table(__func__, "raw skb data dump", skb->data, skb->len);
 167         /* at least two bytes will be used for the encoding */
 168         if (skb->len < 2)
 169                 goto drop;
 170
 171         if (lowpan_fetch_skb_u8(skb, &iphc0))
 172                 goto drop;
 173
 174         if (lowpan_fetch_skb_u8(skb, &iphc1))
 175                 goto drop;
 176
 177         ieee802154_addr_to_sa(&sa, &hdr->source);
 178         ieee802154_addr_to_sa(&da, &hdr->dest);
 179
 180         if (sa.addr_type == IEEE802154_ADDR_SHORT)
 181                 sap = &sa.short_addr;
 182         else
 183                 sap = &sa.hwaddr;
 184
 185         if (da.addr_type == IEEE802154_ADDR_SHORT)
 186                 dap = &da.short_addr;
 187         else
 188                 dap = &da.hwaddr;
 189
 190         return lowpan_process_data(skb, skb->dev, sap, sa.addr_type,
 191                                    IEEE802154_ADDR_LEN, dap, da.addr_type,
 192                                    IEEE802154_ADDR_LEN, iphc0, iphc1,
 193                                    lowpan_give_skb_to_devices);
 194
 195 drop:
 196         kfree_skb(skb);
 197         return -EINVAL;
 198 }
 199
 200 static int lowpan_set_address(struct net_device *dev, void *p)
 201 {
 202         struct sockaddr *sa = p;
 203
 204         if (netif_running(dev))
 205                 return -EBUSY;
 206
 207         /* TODO: validate addr */
 208         memcpy(dev->dev_addr, sa->sa_data, dev->addr_len);
 209
 210         return 0;
 211 }
 212
 213 static struct sk_buff*
 214 lowpan_alloc_frag(struct sk_buff *skb, int size,
 215                   const struct ieee802154_hdr *master_hdr)
 216 {
 217         struct net_device *real_dev = lowpan_dev_info(skb->dev)->real_dev;
 218         struct sk_buff *frag;
 219         int rc;
 220
 221         frag = alloc_skb(real_dev->hard_header_len +
 222                          real_dev->needed_tailroom + size,
 223                          GFP_ATOMIC);
 224
 225         if (likely(frag)) {
 226                 frag->dev = real_dev;
 227                 frag->priority = skb->priority;
 228                 skb_reserve(frag, real_dev->hard_header_len);
 229                 skb_reset_network_header(frag);
 230                 *mac_cb(frag) = *mac_cb(skb);
 231
 232                 rc = dev_hard_header(frag, real_dev, 0, &master_hdr->dest,
 233                                      &master_hdr->source, size);
 234                 if (rc < 0) {
 235                         kfree_skb(frag);
 236                         return ERR_PTR(-rc);
 237                 }
 238         } else {
 239                 frag = ERR_PTR(-ENOMEM);
 240         }
 241
 242         return frag;
 243 }
 244
 245 static int
 246 lowpan_xmit_fragment(struct sk_buff *skb, const struct ieee802154_hdr *wpan_hdr,
 247                      u8 *frag_hdr, int frag_hdrlen,
 248                      int offset, int len)
 249 {
 250         struct sk_buff *frag;
 251
 252         raw_dump_inline(__func__, " fragment header", frag_hdr, frag_hdrlen);
 253
 254         frag = lowpan_alloc_frag(skb, frag_hdrlen + len, wpan_hdr);
 255         if (IS_ERR(frag))
 256                 return -PTR_ERR(frag);
 257
 258         memcpy(skb_put(frag, frag_hdrlen), frag_hdr, frag_hdrlen);
 259         memcpy(skb_put(frag, len), skb_network_header(skb) + offset, len);
 260
 261         raw_dump_table(__func__, " fragment dump", frag->data, frag->len);
 262
 263         return dev_queue_xmit(frag);
 264 }
 265
 266 static int
 267 lowpan_xmit_fragmented(struct sk_buff *skb, struct net_device *dev,
 268                        const struct ieee802154_hdr *wpan_hdr)
 269 {
 270         u16 dgram_size, dgram_offset;
 271         __be16 frag_tag;
 272         u8 frag_hdr[5];
 273         int frag_cap, frag_len, payload_cap, rc;
 274         int skb_unprocessed, skb_offset;
 275
 276         dgram_size = lowpan_uncompress_size(skb, &dgram_offset) -
 277                      skb->mac_len;
 278         frag_tag = lowpan_dev_info(dev)->fragment_tag++;
 279
 280         frag_hdr[0] = LOWPAN_DISPATCH_FRAG1 | ((dgram_size >> 8) & 0x07);
 281         frag_hdr[1] = dgram_size & 0xff;
 282         memcpy(frag_hdr + 2, &frag_tag, sizeof(frag_tag));
 283
 284         payload_cap = ieee802154_max_payload(wpan_hdr);
 285
 286         frag_len = round_down(payload_cap - LOWPAN_FRAG1_HEAD_SIZE -
 287                               skb_network_header_len(skb), 8);
 288
 289         skb_offset = skb_network_header_len(skb);
 290         skb_unprocessed = skb->len - skb->mac_len - skb_offset;
 291
 292         rc = lowpan_xmit_fragment(skb, wpan_hdr, frag_hdr,
 293                                   LOWPAN_FRAG1_HEAD_SIZE, 0,
 294                                   frag_len + skb_network_header_len(skb));
 295         if (rc) {
 296                 pr_debug("%s unable to send FRAG1 packet (tag: %d)",
 297                          __func__, frag_tag);
 298                 goto err;
 299         }
 300
 301         frag_hdr[0] &= ~LOWPAN_DISPATCH_FRAG1;
 302         frag_hdr[0] |= LOWPAN_DISPATCH_FRAGN;
 303         frag_cap = round_down(payload_cap - LOWPAN_FRAGN_HEAD_SIZE, 8);
 304
 305         do {
 306                 dgram_offset += frag_len;
 307                 skb_offset += frag_len;
 308                 skb_unprocessed -= frag_len;
 309                 frag_len = min(frag_cap, skb_unprocessed);
 310
 311                 frag_hdr[4] = dgram_offset >> 3;
 312
 313                 rc = lowpan_xmit_fragment(skb, wpan_hdr, frag_hdr,
 314                                           LOWPAN_FRAGN_HEAD_SIZE, skb_offset,
 315                                           frag_len);
 316                 if (rc) {
 317                         pr_debug("%s unable to send a FRAGN packet. (tag: %d, offset: %d)\n",
 318                                  __func__, frag_tag, skb_offset);
 319                         goto err;
 320                 }
 321         } while (skb_unprocessed > frag_cap);
 322
 323         consume_skb(skb);
 324         return NET_XMIT_SUCCESS;
 325
 326 err:
 327         kfree_skb(skb);
 328         return rc;
 329 }
 330
 331 static int lowpan_header(struct sk_buff *skb, struct net_device *dev)
 332 {
 333         struct ieee802154_addr sa, da;
 334         struct ieee802154_mac_cb *cb = mac_cb_init(skb);
 335         struct lowpan_addr_info info;
 336         void *daddr, *saddr;
 337
 338         memcpy(&info, lowpan_skb_priv(skb), sizeof(info));
 339
 340         /* TODO: Currently we only support extended_addr */
 341         daddr = &info.daddr.u.extended_addr;
 342         saddr = &info.saddr.u.extended_addr;
 343
 344         lowpan_header_compress(skb, dev, ETH_P_IPV6, daddr, saddr, skb->len);
 345
 346         cb->type = IEEE802154_FC_TYPE_DATA;
 347
 348         /* prepare wpan address data */
 349         sa.mode = IEEE802154_ADDR_LONG;
 350         sa.pan_id = ieee802154_mlme_ops(dev)->get_pan_id(dev);
 351         sa.extended_addr = ieee802154_devaddr_from_raw(saddr);
 352
 353         /* intra-PAN communications */
 354         da.pan_id = sa.pan_id;
 355
 356         /* if the destination address is the broadcast address, use the
 357          * corresponding short address
 358          */
 359         if (lowpan_is_addr_broadcast((const u8 *)daddr)) {
 360                 da.mode = IEEE802154_ADDR_SHORT;
 361                 da.short_addr = cpu_to_le16(IEEE802154_ADDR_BROADCAST);
 362                 cb->ackreq = false;
 363         } else {
 364                 da.mode = IEEE802154_ADDR_LONG;
 365                 da.extended_addr = ieee802154_devaddr_from_raw(daddr);
 366                 cb->ackreq = true;
 367         }
 368
 369         return dev_hard_header(skb, lowpan_dev_info(dev)->real_dev,
 370                         ETH_P_IPV6, (void *)&da, (void *)&sa, 0);
 371 }
 372
 373 static netdev_tx_t lowpan_xmit(struct sk_buff *skb, struct net_device *dev)
 374 {
 375         struct ieee802154_hdr wpan_hdr;
 376         int max_single, ret;
 377
 378         pr_debug("package xmit\n");
 379
 380         /* We must take a copy of the skb before we modify/replace the ipv6
 381          * header as the header could be used elsewhere
 382          */
 383         skb = skb_unshare(skb, GFP_ATOMIC);
 384         if (!skb)
 385                 return NET_XMIT_DROP;
 386
 387         ret = lowpan_header(skb, dev);
 388         if (ret < 0) {
 389                 kfree_skb(skb);
 390                 return NET_XMIT_DROP;
 391         }
 392
 393         if (ieee802154_hdr_peek(skb, &wpan_hdr) < 0) {
 394                 kfree_skb(skb);
 395                 return NET_XMIT_DROP;
 396         }
 397
 398         max_single = ieee802154_max_payload(&wpan_hdr);
 399
 400         if (skb_tail_pointer(skb) - skb_network_header(skb) <= max_single) {
 401                 skb->dev = lowpan_dev_info(dev)->real_dev;
 402                 return dev_queue_xmit(skb);
 403         } else {
 404                 netdev_tx_t rc;
 405
 406                 pr_debug("frame is too big, fragmentation is needed\n");
 407                 rc = lowpan_xmit_fragmented(skb, dev, &wpan_hdr);
 408
 409                 return rc < 0 ? NET_XMIT_DROP : rc;
 410         }
 411 }
 412
 413 static struct wpan_phy *lowpan_get_phy(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_phy(real_dev);
 418 }
 419
 420 static __le16 lowpan_get_pan_id(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_pan_id(real_dev);
 425 }
 426
 427 static __le16 lowpan_get_short_addr(const struct net_device *dev)
 428 {
 429         struct net_device *real_dev = lowpan_dev_info(dev)->real_dev;
 430
 431         return ieee802154_mlme_ops(real_dev)->get_short_addr(real_dev);
 432 }
 433
 434 static u8 lowpan_get_dsn(const struct net_device *dev)
 435 {
 436         struct net_device *real_dev = lowpan_dev_info(dev)->real_dev;
 437
 438         return ieee802154_mlme_ops(real_dev)->get_dsn(real_dev);
 439 }
 440
 441 static struct header_ops lowpan_header_ops = {
 442         .create = lowpan_header_create,
 443 };
 444
 445 static struct lock_class_key lowpan_tx_busylock;
 446 static struct lock_class_key lowpan_netdev_xmit_lock_key;
 447
 448 static void lowpan_set_lockdep_class_one(struct net_device *dev,
 449                                          struct netdev_queue *txq,
 450                                          void *_unused)
 451 {
 452         lockdep_set_class(&txq->_xmit_lock,
 453                           &lowpan_netdev_xmit_lock_key);
 454 }
 455
 456
 457 static int lowpan_dev_init(struct net_device *dev)
 458 {
 459         netdev_for_each_tx_queue(dev, lowpan_set_lockdep_class_one, NULL);
 460         dev->qdisc_tx_busylock = &lowpan_tx_busylock;
 461         return 0;
 462 }
 463
 464 static const struct net_device_ops lowpan_netdev_ops = {
 465         .ndo_init               = lowpan_dev_init,
 466         .ndo_start_xmit         = lowpan_xmit,
 467         .ndo_set_mac_address    = lowpan_set_address,
 468 };
 469
 470 static struct ieee802154_mlme_ops lowpan_mlme = {
 471         .get_pan_id = lowpan_get_pan_id,
 472         .get_phy = lowpan_get_phy,
 473         .get_short_addr = lowpan_get_short_addr,
 474         .get_dsn = lowpan_get_dsn,
 475 };
 476
 477 static void lowpan_setup(struct net_device *dev)
 478 {
 479         dev->addr_len           = IEEE802154_ADDR_LEN;
 480         memset(dev->broadcast, 0xff, IEEE802154_ADDR_LEN);
 481         dev->type               = ARPHRD_IEEE802154;
 482         /* Frame Control + Sequence Number + Address fields + Security Header */
 483         dev->hard_header_len    = 2 + 1 + 20 + 14;
 484         dev->needed_tailroom    = 2; /* FCS */
 485         dev->mtu                = IPV6_MIN_MTU;
 486         dev->tx_queue_len       = 0;
 487         dev->flags              = IFF_BROADCAST | IFF_MULTICAST;
 488         dev->watchdog_timeo     = 0;
 489
 490         dev->netdev_ops         = &lowpan_netdev_ops;
 491         dev->header_ops         = &lowpan_header_ops;
 492         dev->ml_priv            = &lowpan_mlme;
 493         dev->destructor         = free_netdev;
 494 }
 495
 496 static int lowpan_validate(struct nlattr *tb[], struct nlattr *data[])
 497 {
 498         if (tb[IFLA_ADDRESS]) {
 499                 if (nla_len(tb[IFLA_ADDRESS]) != IEEE802154_ADDR_LEN)
 500                         return -EINVAL;
 501         }
 502         return 0;
 503 }
 504
 505 static int lowpan_rcv(struct sk_buff *skb, struct net_device *dev,
 506                       struct packet_type *pt, struct net_device *orig_dev)
 507 {
 508         struct ieee802154_hdr hdr;
 509         int ret;
 510
 511         skb = skb_share_check(skb, GFP_ATOMIC);
 512         if (!skb)
 513                 goto drop;
 514
 515         if (!netif_running(dev))
 516                 goto drop_skb;
 517
 518         if (dev->type != ARPHRD_IEEE802154)
 519                 goto drop_skb;
 520
 521         if (ieee802154_hdr_peek_addrs(skb, &hdr) < 0)
 522                 goto drop_skb;
 523
 524         /* check that it's our buffer */
 525         if (skb->data[0] == LOWPAN_DISPATCH_IPV6) {
 526                 skb->protocol = htons(ETH_P_IPV6);
 527                 skb->pkt_type = PACKET_HOST;
 528
 529                 /* Pull off the 1-byte of 6lowpan header. */
 530                 skb_pull(skb, 1);
 531
 532                 ret = lowpan_give_skb_to_devices(skb, NULL);
 533                 if (ret == NET_RX_DROP)
 534                         goto drop;
 535         } else {
 536                 switch (skb->data[0] & 0xe0) {
 537                 case LOWPAN_DISPATCH_IPHC:      /* ipv6 datagram */
 538                         ret = process_data(skb, &hdr);
 539                         if (ret == NET_RX_DROP)
 540                                 goto drop;
 541                         break;
 542                 case LOWPAN_DISPATCH_FRAG1:     /* first fragment header */
 543                         ret = lowpan_frag_rcv(skb, LOWPAN_DISPATCH_FRAG1);
 544                         if (ret == 1) {
 545                                 ret = process_data(skb, &hdr);
 546                                 if (ret == NET_RX_DROP)
 547                                         goto drop;
 548                         }
 549                         break;
 550                 case LOWPAN_DISPATCH_FRAGN:     /* next fragments headers */
 551                         ret = lowpan_frag_rcv(skb, LOWPAN_DISPATCH_FRAGN);
 552                         if (ret == 1) {
 553                                 ret = process_data(skb, &hdr);
 554                                 if (ret == NET_RX_DROP)
 555                                         goto drop;
 556                         }
 557                         break;
 558                 default:
 559                         break;
 560                 }
 561         }
 562
 563         return NET_RX_SUCCESS;
 564 drop_skb:
 565         kfree_skb(skb);
 566 drop:
 567         return NET_RX_DROP;
 568 }
 569
 570 static int lowpan_newlink(struct net *src_net, struct net_device *dev,
 571                           struct nlattr *tb[], struct nlattr *data[])
 572 {
 573         struct net_device *real_dev;
 574         struct lowpan_dev_record *entry;
 575
 576         pr_debug("adding new link\n");
 577
 578         if (!tb[IFLA_LINK])
 579                 return -EINVAL;
 580         /* find and hold real wpan device */
 581         real_dev = dev_get_by_index(src_net, nla_get_u32(tb[IFLA_LINK]));
 582         if (!real_dev)
 583                 return -ENODEV;
 584         if (real_dev->type != ARPHRD_IEEE802154) {
 585                 dev_put(real_dev);
 586                 return -EINVAL;
 587         }
 588
 589         lowpan_dev_info(dev)->real_dev = real_dev;
 590         mutex_init(&lowpan_dev_info(dev)->dev_list_mtx);
 591
 592         entry = kzalloc(sizeof(*entry), GFP_KERNEL);
 593         if (!entry) {
 594                 dev_put(real_dev);
 595                 lowpan_dev_info(dev)->real_dev = NULL;
 596                 return -ENOMEM;
 597         }
 598
 599         entry->ldev = dev;
 600
 601         /* Set the lowpan harware address to the wpan hardware address. */
 602         memcpy(dev->dev_addr, real_dev->dev_addr, IEEE802154_ADDR_LEN);
 603
 604         mutex_lock(&lowpan_dev_info(dev)->dev_list_mtx);
 605         INIT_LIST_HEAD(&entry->list);
 606         list_add_tail(&entry->list, &lowpan_devices);
 607         mutex_unlock(&lowpan_dev_info(dev)->dev_list_mtx);
 608
 609         register_netdevice(dev);
 610
 611         return 0;
 612 }
 613
 614 static void lowpan_dellink(struct net_device *dev, struct list_head *head)
 615 {
 616         struct lowpan_dev_info *lowpan_dev = lowpan_dev_info(dev);
 617         struct net_device *real_dev = lowpan_dev->real_dev;
 618         struct lowpan_dev_record *entry, *tmp;
 619
 620         ASSERT_RTNL();
 621
 622         mutex_lock(&lowpan_dev_info(dev)->dev_list_mtx);
 623         list_for_each_entry_safe(entry, tmp, &lowpan_devices, list) {
 624                 if (entry->ldev == dev) {
 625                         list_del(&entry->list);
 626                         kfree(entry);
 627                 }
 628         }
 629         mutex_unlock(&lowpan_dev_info(dev)->dev_list_mtx);
 630
 631         mutex_destroy(&lowpan_dev_info(dev)->dev_list_mtx);
 632
 633         unregister_netdevice_queue(dev, head);
 634
 635         dev_put(real_dev);
 636 }
 637
 638 static struct rtnl_link_ops lowpan_link_ops __read_mostly = {
 639         .kind           = "lowpan",
 640         .priv_size      = sizeof(struct lowpan_dev_info),
 641         .setup          = lowpan_setup,
 642         .newlink        = lowpan_newlink,
 643         .dellink        = lowpan_dellink,
 644         .validate       = lowpan_validate,
 645 };
 646
 647 static inline int __init lowpan_netlink_init(void)
 648 {
 649         return rtnl_link_register(&lowpan_link_ops);
 650 }
 651
 652 static inline void lowpan_netlink_fini(void)
 653 {
 654         rtnl_link_unregister(&lowpan_link_ops);
 655 }
 656
 657 static int lowpan_device_event(struct notifier_block *unused,
 658                                unsigned long event, void *ptr)
 659 {
 660         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
 661         LIST_HEAD(del_list);
 662         struct lowpan_dev_record *entry, *tmp;
 663
 664         if (dev->type != ARPHRD_IEEE802154)
 665                 goto out;
 666
 667         if (event == NETDEV_UNREGISTER) {
 668                 list_for_each_entry_safe(entry, tmp, &lowpan_devices, list) {
 669                         if (lowpan_dev_info(entry->ldev)->real_dev == dev)
 670                                 lowpan_dellink(entry->ldev, &del_list);
 671                 }
 672
 673                 unregister_netdevice_many(&del_list);
 674         }
 675
 676 out:
 677         return NOTIFY_DONE;
 678 }
 679
 680 static struct notifier_block lowpan_dev_notifier = {
 681         .notifier_call = lowpan_device_event,
 682 };
 683
 684 static struct packet_type lowpan_packet_type = {
 685         .type = htons(ETH_P_IEEE802154),
 686         .func = lowpan_rcv,
 687 };
 688
 689 static int __init lowpan_init_module(void)
 690 {
 691         int err = 0;
 692
 693         err = lowpan_net_frag_init();
 694         if (err < 0)
 695                 goto out;
 696
 697         err = lowpan_netlink_init();
 698         if (err < 0)
 699                 goto out_frag;
 700
 701         dev_add_pack(&lowpan_packet_type);
 702
 703         err = register_netdevice_notifier(&lowpan_dev_notifier);
 704         if (err < 0)
 705                 goto out_pack;
 706
 707         return 0;
 708
 709 out_pack:
 710         dev_remove_pack(&lowpan_packet_type);
 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         dev_remove_pack(&lowpan_packet_type);
 723
 724         lowpan_net_frag_exit();
 725
 726         unregister_netdevice_notifier(&lowpan_dev_notifier);
 727 }
 728
 729 module_init(lowpan_init_module);
 730 module_exit(lowpan_cleanup_module);
 731 MODULE_LICENSE("GPL");
 732 MODULE_ALIAS_RTNL_LINK("lowpan");