net/ipv6/netfilter/ip6_queue.c

   1 /*
   2  * This is a module which is used for queueing IPv6 packets and
   3  * communicating with userspace via netlink.
   4  *
   5  * (C) 2001 Fernando Anton, this code is GPL.
   6  *     IPv64 Project - Work based in IPv64 draft by Arturo Azcorra.
   7  *     Universidad Carlos III de Madrid - Leganes (Madrid) - Spain
   8  *     Universidad Politecnica de Alcala de Henares - Alcala de H. (Madrid) - Spain
   9  *     email: fanton@it.uc3m.es
  10  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License version 2 as
  13  * published by the Free Software Foundation.
  14  */
  15 #include <linux/module.h>
  16 #include <linux/skbuff.h>
  17 #include <linux/init.h>
  18 #include <linux/ipv6.h>
  19 #include <linux/notifier.h>
  20 #include <linux/netdevice.h>
  21 #include <linux/netfilter.h>
  22 #include <linux/netlink.h>
  23 #include <linux/spinlock.h>
  24 #include <linux/sysctl.h>
  25 #include <linux/proc_fs.h>
  26 #include <linux/seq_file.h>
  27 #include <linux/mutex.h>
  28 #include <net/net_namespace.h>
  29 #include <net/sock.h>
  30 #include <net/ipv6.h>
  31 #include <net/ip6_route.h>
  32 #include <net/netfilter/nf_queue.h>
  33 #include <linux/netfilter_ipv4/ip_queue.h>
  34 #include <linux/netfilter_ipv4/ip_tables.h>
  35 #include <linux/netfilter_ipv6/ip6_tables.h>
  36
  37 #define IPQ_QMAX_DEFAULT 1024
  38 #define IPQ_PROC_FS_NAME "ip6_queue"
  39 #define NET_IPQ_QMAX 2088
  40 #define NET_IPQ_QMAX_NAME "ip6_queue_maxlen"
  41
  42 struct ipq_queue_entry {
  43         struct list_head list;
  44         struct nf_info *info;
  45         struct sk_buff *skb;
  46 };
  47
  48 typedef int (*ipq_cmpfn)(struct ipq_queue_entry *, unsigned long);
  49
  50 static unsigned char copy_mode __read_mostly = IPQ_COPY_NONE;
  51 static unsigned int queue_maxlen __read_mostly = IPQ_QMAX_DEFAULT;
  52 static DEFINE_RWLOCK(queue_lock);
  53 static int peer_pid __read_mostly;
  54 static unsigned int copy_range __read_mostly;
  55 static unsigned int queue_total;
  56 static unsigned int queue_dropped = 0;
  57 static unsigned int queue_user_dropped = 0;
  58 static struct sock *ipqnl __read_mostly;
  59 static LIST_HEAD(queue_list);
  60 static DEFINE_MUTEX(ipqnl_mutex);
  61
  62 static void
  63 ipq_issue_verdict(struct ipq_queue_entry *entry, int verdict)
  64 {
  65         local_bh_disable();
  66         nf_reinject(entry->skb, entry->info, verdict);
  67         local_bh_enable();
  68         kfree(entry);
  69 }
  70
  71 static inline void
  72 __ipq_enqueue_entry(struct ipq_queue_entry *entry)
  73 {
  74        list_add(&entry->list, &queue_list);
  75        queue_total++;
  76 }
  77
  78 /*
  79  * Find and return a queued entry matched by cmpfn, or return the last
  80  * entry if cmpfn is NULL.
  81  */
  82 static inline struct ipq_queue_entry *
  83 __ipq_find_entry(ipq_cmpfn cmpfn, unsigned long data)
  84 {
  85         struct list_head *p;
  86
  87         list_for_each_prev(p, &queue_list) {
  88                 struct ipq_queue_entry *entry = (struct ipq_queue_entry *)p;
  89
  90                 if (!cmpfn || cmpfn(entry, data))
  91                         return entry;
  92         }
  93         return NULL;
  94 }
  95
  96 static inline void
  97 __ipq_dequeue_entry(struct ipq_queue_entry *entry)
  98 {
  99         list_del(&entry->list);
 100         queue_total--;
 101 }
 102
 103 static inline struct ipq_queue_entry *
 104 __ipq_find_dequeue_entry(ipq_cmpfn cmpfn, unsigned long data)
 105 {
 106         struct ipq_queue_entry *entry;
 107
 108         entry = __ipq_find_entry(cmpfn, data);
 109         if (entry == NULL)
 110                 return NULL;
 111
 112         __ipq_dequeue_entry(entry);
 113         return entry;
 114 }
 115
 116
 117 static inline void
 118 __ipq_flush(int verdict)
 119 {
 120         struct ipq_queue_entry *entry;
 121
 122         while ((entry = __ipq_find_dequeue_entry(NULL, 0)))
 123                 ipq_issue_verdict(entry, verdict);
 124 }
 125
 126 static inline int
 127 __ipq_set_mode(unsigned char mode, unsigned int range)
 128 {
 129         int status = 0;
 130
 131         switch(mode) {
 132         case IPQ_COPY_NONE:
 133         case IPQ_COPY_META:
 134                 copy_mode = mode;
 135                 copy_range = 0;
 136                 break;
 137
 138         case IPQ_COPY_PACKET:
 139                 copy_mode = mode;
 140                 copy_range = range;
 141                 if (copy_range > 0xFFFF)
 142                         copy_range = 0xFFFF;
 143                 break;
 144
 145         default:
 146                 status = -EINVAL;
 147
 148         }
 149         return status;
 150 }
 151
 152 static inline void
 153 __ipq_reset(void)
 154 {
 155         peer_pid = 0;
 156         net_disable_timestamp();
 157         __ipq_set_mode(IPQ_COPY_NONE, 0);
 158         __ipq_flush(NF_DROP);
 159 }
 160
 161 static struct ipq_queue_entry *
 162 ipq_find_dequeue_entry(ipq_cmpfn cmpfn, unsigned long data)
 163 {
 164         struct ipq_queue_entry *entry;
 165
 166         write_lock_bh(&queue_lock);
 167         entry = __ipq_find_dequeue_entry(cmpfn, data);
 168         write_unlock_bh(&queue_lock);
 169         return entry;
 170 }
 171
 172 static void
 173 ipq_flush(int verdict)
 174 {
 175         write_lock_bh(&queue_lock);
 176         __ipq_flush(verdict);
 177         write_unlock_bh(&queue_lock);
 178 }
 179
 180 static struct sk_buff *
 181 ipq_build_packet_message(struct ipq_queue_entry *entry, int *errp)
 182 {
 183         sk_buff_data_t old_tail;
 184         size_t size = 0;
 185         size_t data_len = 0;
 186         struct sk_buff *skb;
 187         struct ipq_packet_msg *pmsg;
 188         struct nlmsghdr *nlh;
 189         struct timeval tv;
 190
 191         read_lock_bh(&queue_lock);
 192
 193         switch (copy_mode) {
 194         case IPQ_COPY_META:
 195         case IPQ_COPY_NONE:
 196                 size = NLMSG_SPACE(sizeof(*pmsg));
 197                 data_len = 0;
 198                 break;
 199
 200         case IPQ_COPY_PACKET:
 201                 if ((entry->skb->ip_summed == CHECKSUM_PARTIAL ||
 202                      entry->skb->ip_summed == CHECKSUM_COMPLETE) &&
 203                     (*errp = skb_checksum_help(entry->skb))) {
 204                         read_unlock_bh(&queue_lock);
 205                         return NULL;
 206                 }
 207                 if (copy_range == 0 || copy_range > entry->skb->len)
 208                         data_len = entry->skb->len;
 209                 else
 210                         data_len = copy_range;
 211
 212                 size = NLMSG_SPACE(sizeof(*pmsg) + data_len);
 213                 break;
 214
 215         default:
 216                 *errp = -EINVAL;
 217                 read_unlock_bh(&queue_lock);
 218                 return NULL;
 219         }
 220
 221         read_unlock_bh(&queue_lock);
 222
 223         skb = alloc_skb(size, GFP_ATOMIC);
 224         if (!skb)
 225                 goto nlmsg_failure;
 226
 227         old_tail = skb->tail;
 228         nlh = NLMSG_PUT(skb, 0, 0, IPQM_PACKET, size - sizeof(*nlh));
 229         pmsg = NLMSG_DATA(nlh);
 230         memset(pmsg, 0, sizeof(*pmsg));
 231
 232         pmsg->packet_id       = (unsigned long )entry;
 233         pmsg->data_len        = data_len;
 234         tv = ktime_to_timeval(entry->skb->tstamp);
 235         pmsg->timestamp_sec   = tv.tv_sec;
 236         pmsg->timestamp_usec  = tv.tv_usec;
 237         pmsg->mark            = entry->skb->mark;
 238         pmsg->hook            = entry->info->hook;
 239         pmsg->hw_protocol     = entry->skb->protocol;
 240
 241         if (entry->info->indev)
 242                 strcpy(pmsg->indev_name, entry->info->indev->name);
 243         else
 244                 pmsg->indev_name[0] = '\0';
 245
 246         if (entry->info->outdev)
 247                 strcpy(pmsg->outdev_name, entry->info->outdev->name);
 248         else
 249                 pmsg->outdev_name[0] = '\0';
 250
 251         if (entry->info->indev && entry->skb->dev) {
 252                 pmsg->hw_type = entry->skb->dev->type;
 253                 pmsg->hw_addrlen = dev_parse_header(entry->skb, pmsg->hw_addr);
 254         }
 255
 256         if (data_len)
 257                 if (skb_copy_bits(entry->skb, 0, pmsg->payload, data_len))
 258                         BUG();
 259
 260         nlh->nlmsg_len = skb->tail - old_tail;
 261         return skb;
 262
 263 nlmsg_failure:
 264         if (skb)
 265                 kfree_skb(skb);
 266         *errp = -EINVAL;
 267         printk(KERN_ERR "ip6_queue: error creating packet message\n");
 268         return NULL;
 269 }
 270
 271 static int
 272 ipq_enqueue_packet(struct sk_buff *skb, struct nf_info *info,
 273                    unsigned int queuenum)
 274 {
 275         int status = -EINVAL;
 276         struct sk_buff *nskb;
 277         struct ipq_queue_entry *entry;
 278
 279         if (copy_mode == IPQ_COPY_NONE)
 280                 return -EAGAIN;
 281
 282         entry = kmalloc(sizeof(*entry), GFP_ATOMIC);
 283         if (entry == NULL) {
 284                 printk(KERN_ERR "ip6_queue: OOM in ipq_enqueue_packet()\n");
 285                 return -ENOMEM;
 286         }
 287
 288         entry->info = info;
 289         entry->skb = skb;
 290
 291         nskb = ipq_build_packet_message(entry, &status);
 292         if (nskb == NULL)
 293                 goto err_out_free;
 294
 295         write_lock_bh(&queue_lock);
 296
 297         if (!peer_pid)
 298                 goto err_out_free_nskb;
 299
 300         if (queue_total >= queue_maxlen) {
 301                 queue_dropped++;
 302                 status = -ENOSPC;
 303                 if (net_ratelimit())
 304                         printk (KERN_WARNING "ip6_queue: fill at %d entries, "
 305                                 "dropping packet(s).  Dropped: %d\n", queue_total,
 306                                 queue_dropped);
 307                 goto err_out_free_nskb;
 308         }
 309
 310         /* netlink_unicast will either free the nskb or attach it to a socket */
 311         status = netlink_unicast(ipqnl, nskb, peer_pid, MSG_DONTWAIT);
 312         if (status < 0) {
 313                 queue_user_dropped++;
 314                 goto err_out_unlock;
 315         }
 316
 317         __ipq_enqueue_entry(entry);
 318
 319         write_unlock_bh(&queue_lock);
 320         return status;
 321
 322 err_out_free_nskb:
 323         kfree_skb(nskb);
 324
 325 err_out_unlock:
 326         write_unlock_bh(&queue_lock);
 327
 328 err_out_free:
 329         kfree(entry);
 330         return status;
 331 }
 332
 333 static int
 334 ipq_mangle_ipv6(ipq_verdict_msg_t *v, struct ipq_queue_entry *e)
 335 {
 336         int diff;
 337         int err;
 338         struct ipv6hdr *user_iph = (struct ipv6hdr *)v->payload;
 339
 340         if (v->data_len < sizeof(*user_iph))
 341                 return 0;
 342         diff = v->data_len - e->skb->len;
 343         if (diff < 0) {
 344                 if (pskb_trim(e->skb, v->data_len))
 345                         return -ENOMEM;
 346         } else if (diff > 0) {
 347                 if (v->data_len > 0xFFFF)
 348                         return -EINVAL;
 349                 if (diff > skb_tailroom(e->skb)) {
 350                         err = pskb_expand_head(e->skb, 0,
 351                                                diff - skb_tailroom(e->skb),
 352                                                GFP_ATOMIC);
 353                         if (err) {
 354                                 printk(KERN_WARNING "ip6_queue: OOM "
 355                                       "in mangle, dropping packet\n");
 356                                 return err;
 357                         }
 358                 }
 359                 skb_put(e->skb, diff);
 360         }
 361         if (!skb_make_writable(e->skb, v->data_len))
 362                 return -ENOMEM;
 363         skb_copy_to_linear_data(e->skb, v->payload, v->data_len);
 364         e->skb->ip_summed = CHECKSUM_NONE;
 365
 366         return 0;
 367 }
 368
 369 static inline int
 370 id_cmp(struct ipq_queue_entry *e, unsigned long id)
 371 {
 372         return (id == (unsigned long )e);
 373 }
 374
 375 static int
 376 ipq_set_verdict(struct ipq_verdict_msg *vmsg, unsigned int len)
 377 {
 378         struct ipq_queue_entry *entry;
 379
 380         if (vmsg->value > NF_MAX_VERDICT)
 381                 return -EINVAL;
 382
 383         entry = ipq_find_dequeue_entry(id_cmp, vmsg->id);
 384         if (entry == NULL)
 385                 return -ENOENT;
 386         else {
 387                 int verdict = vmsg->value;
 388
 389                 if (vmsg->data_len && vmsg->data_len == len)
 390                         if (ipq_mangle_ipv6(vmsg, entry) < 0)
 391                                 verdict = NF_DROP;
 392
 393                 ipq_issue_verdict(entry, verdict);
 394                 return 0;
 395         }
 396 }
 397
 398 static int
 399 ipq_set_mode(unsigned char mode, unsigned int range)
 400 {
 401         int status;
 402
 403         write_lock_bh(&queue_lock);
 404         status = __ipq_set_mode(mode, range);
 405         write_unlock_bh(&queue_lock);
 406         return status;
 407 }
 408
 409 static int
 410 ipq_receive_peer(struct ipq_peer_msg *pmsg,
 411                  unsigned char type, unsigned int len)
 412 {
 413         int status = 0;
 414
 415         if (len < sizeof(*pmsg))
 416                 return -EINVAL;
 417
 418         switch (type) {
 419         case IPQM_MODE:
 420                 status = ipq_set_mode(pmsg->msg.mode.value,
 421                                       pmsg->msg.mode.range);
 422                 break;
 423
 424         case IPQM_VERDICT:
 425                 if (pmsg->msg.verdict.value > NF_MAX_VERDICT)
 426                         status = -EINVAL;
 427                 else
 428                         status = ipq_set_verdict(&pmsg->msg.verdict,
 429                                                  len - sizeof(*pmsg));
 430                         break;
 431         default:
 432                 status = -EINVAL;
 433         }
 434         return status;
 435 }
 436
 437 static int
 438 dev_cmp(struct ipq_queue_entry *entry, unsigned long ifindex)
 439 {
 440         if (entry->info->indev)
 441                 if (entry->info->indev->ifindex == ifindex)
 442                         return 1;
 443
 444         if (entry->info->outdev)
 445                 if (entry->info->outdev->ifindex == ifindex)
 446                         return 1;
 447
 448         return 0;
 449 }
 450
 451 static void
 452 ipq_dev_drop(int ifindex)
 453 {
 454         struct ipq_queue_entry *entry;
 455
 456         while ((entry = ipq_find_dequeue_entry(dev_cmp, ifindex)) != NULL)
 457                 ipq_issue_verdict(entry, NF_DROP);
 458 }
 459
 460 #define RCV_SKB_FAIL(err) do { netlink_ack(skb, nlh, (err)); return; } while (0)
 461
 462 static inline void
 463 __ipq_rcv_skb(struct sk_buff *skb)
 464 {
 465         int status, type, pid, flags, nlmsglen, skblen;
 466         struct nlmsghdr *nlh;
 467
 468         skblen = skb->len;
 469         if (skblen < sizeof(*nlh))
 470                 return;
 471
 472         nlh = nlmsg_hdr(skb);
 473         nlmsglen = nlh->nlmsg_len;
 474         if (nlmsglen < sizeof(*nlh) || skblen < nlmsglen)
 475                 return;
 476
 477         pid = nlh->nlmsg_pid;
 478         flags = nlh->nlmsg_flags;
 479
 480         if(pid <= 0 || !(flags & NLM_F_REQUEST) || flags & NLM_F_MULTI)
 481                 RCV_SKB_FAIL(-EINVAL);
 482
 483         if (flags & MSG_TRUNC)
 484                 RCV_SKB_FAIL(-ECOMM);
 485
 486         type = nlh->nlmsg_type;
 487         if (type < NLMSG_NOOP || type >= IPQM_MAX)
 488                 RCV_SKB_FAIL(-EINVAL);
 489
 490         if (type <= IPQM_BASE)
 491                 return;
 492
 493         if (security_netlink_recv(skb, CAP_NET_ADMIN))
 494                 RCV_SKB_FAIL(-EPERM);
 495
 496         write_lock_bh(&queue_lock);
 497
 498         if (peer_pid) {
 499                 if (peer_pid != pid) {
 500                         write_unlock_bh(&queue_lock);
 501                         RCV_SKB_FAIL(-EBUSY);
 502                 }
 503         } else {
 504                 net_enable_timestamp();
 505                 peer_pid = pid;
 506         }
 507
 508         write_unlock_bh(&queue_lock);
 509
 510         status = ipq_receive_peer(NLMSG_DATA(nlh), type,
 511                                   nlmsglen - NLMSG_LENGTH(0));
 512         if (status < 0)
 513                 RCV_SKB_FAIL(status);
 514
 515         if (flags & NLM_F_ACK)
 516                 netlink_ack(skb, nlh, 0);
 517         return;
 518 }
 519
 520 static void
 521 ipq_rcv_skb(struct sk_buff *skb)
 522 {
 523         mutex_lock(&ipqnl_mutex);
 524         __ipq_rcv_skb(skb);
 525         mutex_unlock(&ipqnl_mutex);
 526 }
 527
 528 static int
 529 ipq_rcv_dev_event(struct notifier_block *this,
 530                   unsigned long event, void *ptr)
 531 {
 532         struct net_device *dev = ptr;
 533
 534         if (dev->nd_net != &init_net)
 535                 return NOTIFY_DONE;
 536
 537         /* Drop any packets associated with the downed device */
 538         if (event == NETDEV_DOWN)
 539                 ipq_dev_drop(dev->ifindex);
 540         return NOTIFY_DONE;
 541 }
 542
 543 static struct notifier_block ipq_dev_notifier = {
 544         .notifier_call  = ipq_rcv_dev_event,
 545 };
 546
 547 static int
 548 ipq_rcv_nl_event(struct notifier_block *this,
 549                  unsigned long event, void *ptr)
 550 {
 551         struct netlink_notify *n = ptr;
 552
 553         if (event == NETLINK_URELEASE &&
 554             n->protocol == NETLINK_IP6_FW && n->pid) {
 555                 write_lock_bh(&queue_lock);
 556                 if ((n->net == &init_net) && (n->pid == peer_pid))
 557                         __ipq_reset();
 558                 write_unlock_bh(&queue_lock);
 559         }
 560         return NOTIFY_DONE;
 561 }
 562
 563 static struct notifier_block ipq_nl_notifier = {
 564         .notifier_call  = ipq_rcv_nl_event,
 565 };
 566
 567 static struct ctl_table_header *ipq_sysctl_header;
 568
 569 static ctl_table ipq_table[] = {
 570         {
 571                 .ctl_name       = NET_IPQ_QMAX,
 572                 .procname       = NET_IPQ_QMAX_NAME,
 573                 .data           = &queue_maxlen,
 574                 .maxlen         = sizeof(queue_maxlen),
 575                 .mode           = 0644,
 576                 .proc_handler   = proc_dointvec
 577         },
 578         { .ctl_name = 0 }
 579 };
 580
 581 static ctl_table ipq_dir_table[] = {
 582         {
 583                 .ctl_name       = NET_IPV6,
 584                 .procname       = "ipv6",
 585                 .mode           = 0555,
 586                 .child          = ipq_table
 587         },
 588         { .ctl_name = 0 }
 589 };
 590
 591 static ctl_table ipq_root_table[] = {
 592         {
 593                 .ctl_name       = CTL_NET,
 594                 .procname       = "net",
 595                 .mode           = 0555,
 596                 .child          = ipq_dir_table
 597         },
 598         { .ctl_name = 0 }
 599 };
 600
 601 static int ip6_queue_show(struct seq_file *m, void *v)
 602 {
 603         read_lock_bh(&queue_lock);
 604
 605         seq_printf(m,
 606                       "Peer PID          : %d\n"
 607                       "Copy mode         : %hu\n"
 608                       "Copy range        : %u\n"
 609                       "Queue length      : %u\n"
 610                       "Queue max. length : %u\n"
 611                       "Queue dropped     : %u\n"
 612                       "Netfilter dropped : %u\n",
 613                       peer_pid,
 614                       copy_mode,
 615                       copy_range,
 616                       queue_total,
 617                       queue_maxlen,
 618                       queue_dropped,
 619                       queue_user_dropped);
 620
 621         read_unlock_bh(&queue_lock);
 622         return 0;
 623 }
 624
 625 static int ip6_queue_open(struct inode *inode, struct file *file)
 626 {
 627         return single_open(file, ip6_queue_show, NULL);
 628 }
 629
 630 static const struct file_operations ip6_queue_proc_fops = {
 631         .open           = ip6_queue_open,
 632         .read           = seq_read,
 633         .llseek         = seq_lseek,
 634         .release        = single_release,
 635         .owner          = THIS_MODULE,
 636 };
 637
 638 static const struct nf_queue_handler nfqh = {
 639         .name   = "ip6_queue",
 640         .outfn  = &ipq_enqueue_packet,
 641 };
 642
 643 static int __init ip6_queue_init(void)
 644 {
 645         int status = -ENOMEM;
 646         struct proc_dir_entry *proc;
 647
 648         netlink_register_notifier(&ipq_nl_notifier);
 649         ipqnl = netlink_kernel_create(&init_net, NETLINK_IP6_FW, 0,
 650                                       ipq_rcv_skb, NULL, THIS_MODULE);
 651         if (ipqnl == NULL) {
 652                 printk(KERN_ERR "ip6_queue: failed to create netlink socket\n");
 653                 goto cleanup_netlink_notifier;
 654         }
 655
 656         proc = create_proc_entry(IPQ_PROC_FS_NAME, 0, init_net.proc_net);
 657         if (proc) {
 658                 proc->owner = THIS_MODULE;
 659                 proc->proc_fops = &ip6_queue_proc_fops;
 660         } else {
 661                 printk(KERN_ERR "ip6_queue: failed to create proc entry\n");
 662                 goto cleanup_ipqnl;
 663         }
 664
 665         register_netdevice_notifier(&ipq_dev_notifier);
 666         ipq_sysctl_header = register_sysctl_table(ipq_root_table);
 667
 668         status = nf_register_queue_handler(PF_INET6, &nfqh);
 669         if (status < 0) {
 670                 printk(KERN_ERR "ip6_queue: failed to register queue handler\n");
 671                 goto cleanup_sysctl;
 672         }
 673         return status;
 674
 675 cleanup_sysctl:
 676         unregister_sysctl_table(ipq_sysctl_header);
 677         unregister_netdevice_notifier(&ipq_dev_notifier);
 678         proc_net_remove(&init_net, IPQ_PROC_FS_NAME);
 679
 680 cleanup_ipqnl:
 681         sock_release(ipqnl->sk_socket);
 682         mutex_lock(&ipqnl_mutex);
 683         mutex_unlock(&ipqnl_mutex);
 684
 685 cleanup_netlink_notifier:
 686         netlink_unregister_notifier(&ipq_nl_notifier);
 687         return status;
 688 }
 689
 690 static void __exit ip6_queue_fini(void)
 691 {
 692         nf_unregister_queue_handlers(&nfqh);
 693         synchronize_net();
 694         ipq_flush(NF_DROP);
 695
 696         unregister_sysctl_table(ipq_sysctl_header);
 697         unregister_netdevice_notifier(&ipq_dev_notifier);
 698         proc_net_remove(&init_net, IPQ_PROC_FS_NAME);
 699
 700         sock_release(ipqnl->sk_socket);
 701         mutex_lock(&ipqnl_mutex);
 702         mutex_unlock(&ipqnl_mutex);
 703
 704         netlink_unregister_notifier(&ipq_nl_notifier);
 705 }
 706
 707 MODULE_DESCRIPTION("IPv6 packet queue handler");
 708 MODULE_LICENSE("GPL");
 709
 710 module_init(ip6_queue_init);
 711 module_exit(ip6_queue_fini);