git.oblomov.eu Git - linux-2.6/blob - 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 <linux/netfilter_ipv4/ip_queue.h>
  33 #include <linux/netfilter_ipv4/ip_tables.h>
  34 #include <linux/netfilter_ipv6/ip6_tables.h>
  35
  36 #define IPQ_QMAX_DEFAULT 1024
  37 #define IPQ_PROC_FS_NAME "ip6_queue"
  38 #define NET_IPQ_QMAX 2088
  39 #define NET_IPQ_QMAX_NAME "ip6_queue_maxlen"
  40
  41 struct ipq_queue_entry {
  42         struct list_head list;
  43         struct nf_info *info;
  44         struct sk_buff *skb;
  45 };
  46
  47 typedef int (*ipq_cmpfn)(struct ipq_queue_entry *, unsigned long);
  48
  49 static unsigned char copy_mode __read_mostly = IPQ_COPY_NONE;
  50 static unsigned int queue_maxlen __read_mostly = IPQ_QMAX_DEFAULT;
  51 static DEFINE_RWLOCK(queue_lock);
  52 static int peer_pid __read_mostly;
  53 static unsigned int copy_range __read_mostly;
  54 static unsigned int queue_total;
  55 static unsigned int queue_dropped = 0;
  56 static unsigned int queue_user_dropped = 0;
  57 static struct sock *ipqnl __read_mostly;
  58 static LIST_HEAD(queue_list);
  59 static DEFINE_MUTEX(ipqnl_mutex);
  60
  61 static void
  62 ipq_issue_verdict(struct ipq_queue_entry *entry, int verdict)
  63 {
  64         local_bh_disable();
  65         nf_reinject(entry->skb, entry->info, verdict);
  66         local_bh_enable();
  67         kfree(entry);
  68 }
  69
  70 static inline void
  71 __ipq_enqueue_entry(struct ipq_queue_entry *entry)
  72 {
  73        list_add(&entry->list, &queue_list);
  74        queue_total++;
  75 }
  76
  77 /*
  78  * Find and return a queued entry matched by cmpfn, or return the last
  79  * entry if cmpfn is NULL.
  80  */
  81 static inline struct ipq_queue_entry *
  82 __ipq_find_entry(ipq_cmpfn cmpfn, unsigned long data)
  83 {
  84         struct list_head *p;
  85
  86         list_for_each_prev(p, &queue_list) {
  87                 struct ipq_queue_entry *entry = (struct ipq_queue_entry *)p;
  88
  89                 if (!cmpfn || cmpfn(entry, data))
  90                         return entry;
  91         }
  92         return NULL;
  93 }
  94
  95 static inline void
  96 __ipq_dequeue_entry(struct ipq_queue_entry *entry)
  97 {
  98         list_del(&entry->list);
  99         queue_total--;
 100 }
 101
 102 static inline struct ipq_queue_entry *
 103 __ipq_find_dequeue_entry(ipq_cmpfn cmpfn, unsigned long data)
 104 {
 105         struct ipq_queue_entry *entry;
 106
 107         entry = __ipq_find_entry(cmpfn, data);
 108         if (entry == NULL)
 109                 return NULL;
 110
 111         __ipq_dequeue_entry(entry);
 112         return entry;
 113 }
 114
 115
 116 static inline void
 117 __ipq_flush(int verdict)
 118 {
 119         struct ipq_queue_entry *entry;
 120
 121         while ((entry = __ipq_find_dequeue_entry(NULL, 0)))
 122                 ipq_issue_verdict(entry, verdict);
 123 }
 124
 125 static inline int
 126 __ipq_set_mode(unsigned char mode, unsigned int range)
 127 {
 128         int status = 0;
 129
 130         switch(mode) {
 131         case IPQ_COPY_NONE:
 132         case IPQ_COPY_META:
 133                 copy_mode = mode;
 134                 copy_range = 0;
 135                 break;
 136
 137         case IPQ_COPY_PACKET:
 138                 copy_mode = mode;
 139                 copy_range = range;
 140                 if (copy_range > 0xFFFF)
 141                         copy_range = 0xFFFF;
 142                 break;
 143
 144         default:
 145                 status = -EINVAL;
 146
 147         }
 148         return status;
 149 }
 150
 151 static inline void
 152 __ipq_reset(void)
 153 {
 154         peer_pid = 0;
 155         net_disable_timestamp();
 156         __ipq_set_mode(IPQ_COPY_NONE, 0);
 157         __ipq_flush(NF_DROP);
 158 }
 159
 160 static struct ipq_queue_entry *
 161 ipq_find_dequeue_entry(ipq_cmpfn cmpfn, unsigned long data)
 162 {
 163         struct ipq_queue_entry *entry;
 164
 165         write_lock_bh(&queue_lock);
 166         entry = __ipq_find_dequeue_entry(cmpfn, data);
 167         write_unlock_bh(&queue_lock);
 168         return entry;
 169 }
 170
 171 static void
 172 ipq_flush(int verdict)
 173 {
 174         write_lock_bh(&queue_lock);
 175         __ipq_flush(verdict);
 176         write_unlock_bh(&queue_lock);
 177 }
 178
 179 static struct sk_buff *
 180 ipq_build_packet_message(struct ipq_queue_entry *entry, int *errp)
 181 {
 182         sk_buff_data_t old_tail;
 183         size_t size = 0;
 184         size_t data_len = 0;
 185         struct sk_buff *skb;
 186         struct ipq_packet_msg *pmsg;
 187         struct nlmsghdr *nlh;
 188         struct timeval tv;
 189
 190         read_lock_bh(&queue_lock);
 191
 192         switch (copy_mode) {
 193         case IPQ_COPY_META:
 194         case IPQ_COPY_NONE:
 195                 size = NLMSG_SPACE(sizeof(*pmsg));
 196                 data_len = 0;
 197                 break;
 198
 199         case IPQ_COPY_PACKET:
 200                 if ((entry->skb->ip_summed == CHECKSUM_PARTIAL ||
 201                      entry->skb->ip_summed == CHECKSUM_COMPLETE) &&
 202                     (*errp = skb_checksum_help(entry->skb))) {
 203                         read_unlock_bh(&queue_lock);
 204                         return NULL;
 205                 }
 206                 if (copy_range == 0 || copy_range > entry->skb->len)
 207                         data_len = entry->skb->len;
 208                 else
 209                         data_len = copy_range;
 210
 211                 size = NLMSG_SPACE(sizeof(*pmsg) + data_len);
 212                 break;
 213
 214         default:
 215                 *errp = -EINVAL;
 216                 read_unlock_bh(&queue_lock);
 217                 return NULL;
 218         }
 219
 220         read_unlock_bh(&queue_lock);
 221
 222         skb = alloc_skb(size, GFP_ATOMIC);
 223         if (!skb)
 224                 goto nlmsg_failure;
 225
 226         old_tail = skb->tail;
 227         nlh = NLMSG_PUT(skb, 0, 0, IPQM_PACKET, size - sizeof(*nlh));
 228         pmsg = NLMSG_DATA(nlh);
 229         memset(pmsg, 0, sizeof(*pmsg));
 230
 231         pmsg->packet_id       = (unsigned long )entry;
 232         pmsg->data_len        = data_len;
 233         tv = ktime_to_timeval(entry->skb->tstamp);
 234         pmsg->timestamp_sec   = tv.tv_sec;
 235         pmsg->timestamp_usec  = tv.tv_usec;
 236         pmsg->mark            = entry->skb->mark;
 237         pmsg->hook            = entry->info->hook;
 238         pmsg->hw_protocol     = entry->skb->protocol;
 239
 240         if (entry->info->indev)
 241                 strcpy(pmsg->indev_name, entry->info->indev->name);
 242         else
 243                 pmsg->indev_name[0] = '\0';
 244
 245         if (entry->info->outdev)
 246                 strcpy(pmsg->outdev_name, entry->info->outdev->name);
 247         else
 248                 pmsg->outdev_name[0] = '\0';
 249
 250         if (entry->info->indev && entry->skb->dev) {
 251                 pmsg->hw_type = entry->skb->dev->type;
 252                 pmsg->hw_addrlen = dev_parse_header(entry->skb, pmsg->hw_addr);
 253         }
 254
 255         if (data_len)
 256                 if (skb_copy_bits(entry->skb, 0, pmsg->payload, data_len))
 257                         BUG();
 258
 259         nlh->nlmsg_len = skb->tail - old_tail;
 260         return skb;
 261
 262 nlmsg_failure:
 263         if (skb)
 264                 kfree_skb(skb);
 265         *errp = -EINVAL;
 266         printk(KERN_ERR "ip6_queue: error creating packet message\n");
 267         return NULL;
 268 }
 269
 270 static int
 271 ipq_enqueue_packet(struct sk_buff *skb, struct nf_info *info,
 272                    unsigned int queuenum, void *data)
 273 {
 274         int status = -EINVAL;
 275         struct sk_buff *nskb;
 276         struct ipq_queue_entry *entry;
 277
 278         if (copy_mode == IPQ_COPY_NONE)
 279                 return -EAGAIN;
 280
 281         entry = kmalloc(sizeof(*entry), GFP_ATOMIC);
 282         if (entry == NULL) {
 283                 printk(KERN_ERR "ip6_queue: OOM in ipq_enqueue_packet()\n");
 284                 return -ENOMEM;
 285         }
 286
 287         entry->info = info;
 288         entry->skb = skb;
 289
 290         nskb = ipq_build_packet_message(entry, &status);
 291         if (nskb == NULL)
 292                 goto err_out_free;
 293
 294         write_lock_bh(&queue_lock);
 295
 296         if (!peer_pid)
 297                 goto err_out_free_nskb;
 298
 299         if (queue_total >= queue_maxlen) {
 300                 queue_dropped++;
 301                 status = -ENOSPC;
 302                 if (net_ratelimit())
 303                         printk (KERN_WARNING "ip6_queue: fill at %d entries, "
 304                                 "dropping packet(s).  Dropped: %d\n", queue_total,
 305                                 queue_dropped);
 306                 goto err_out_free_nskb;
 307         }
 308
 309         /* netlink_unicast will either free the nskb or attach it to a socket */
 310         status = netlink_unicast(ipqnl, nskb, peer_pid, MSG_DONTWAIT);
 311         if (status < 0) {
 312                 queue_user_dropped++;
 313                 goto err_out_unlock;
 314         }
 315
 316         __ipq_enqueue_entry(entry);
 317
 318         write_unlock_bh(&queue_lock);
 319         return status;
 320
 321 err_out_free_nskb:
 322         kfree_skb(nskb);
 323
 324 err_out_unlock:
 325         write_unlock_bh(&queue_lock);
 326
 327 err_out_free:
 328         kfree(entry);
 329         return status;
 330 }
 331
 332 static int
 333 ipq_mangle_ipv6(ipq_verdict_msg_t *v, struct ipq_queue_entry *e)
 334 {
 335         int diff;
 336         int err;
 337         struct ipv6hdr *user_iph = (struct ipv6hdr *)v->payload;
 338
 339         if (v->data_len < sizeof(*user_iph))
 340                 return 0;
 341         diff = v->data_len - e->skb->len;
 342         if (diff < 0) {
 343                 if (pskb_trim(e->skb, v->data_len))
 344                         return -ENOMEM;
 345         } else if (diff > 0) {
 346                 if (v->data_len > 0xFFFF)
 347                         return -EINVAL;
 348                 if (diff > skb_tailroom(e->skb)) {
 349                         err = pskb_expand_head(e->skb, 0,
 350                                                diff - skb_tailroom(e->skb),
 351                                                GFP_ATOMIC);
 352                         if (err) {
 353                                 printk(KERN_WARNING "ip6_queue: OOM "
 354                                       "in mangle, dropping packet\n");
 355                                 return err;
 356                         }
 357                 }
 358                 skb_put(e->skb, diff);
 359         }
 360         if (!skb_make_writable(e->skb, v->data_len))
 361                 return -ENOMEM;
 362         skb_copy_to_linear_data(e->skb, v->payload, v->data_len);
 363         e->skb->ip_summed = CHECKSUM_NONE;
 364
 365         return 0;
 366 }
 367
 368 static inline int
 369 id_cmp(struct ipq_queue_entry *e, unsigned long id)
 370 {
 371         return (id == (unsigned long )e);
 372 }
 373
 374 static int
 375 ipq_set_verdict(struct ipq_verdict_msg *vmsg, unsigned int len)
 376 {
 377         struct ipq_queue_entry *entry;
 378
 379         if (vmsg->value > NF_MAX_VERDICT)
 380                 return -EINVAL;
 381
 382         entry = ipq_find_dequeue_entry(id_cmp, vmsg->id);
 383         if (entry == NULL)
 384                 return -ENOENT;
 385         else {
 386                 int verdict = vmsg->value;
 387
 388                 if (vmsg->data_len && vmsg->data_len == len)
 389                         if (ipq_mangle_ipv6(vmsg, entry) < 0)
 390                                 verdict = NF_DROP;
 391
 392                 ipq_issue_verdict(entry, verdict);
 393                 return 0;
 394         }
 395 }
 396
 397 static int
 398 ipq_set_mode(unsigned char mode, unsigned int range)
 399 {
 400         int status;
 401
 402         write_lock_bh(&queue_lock);
 403         status = __ipq_set_mode(mode, range);
 404         write_unlock_bh(&queue_lock);
 405         return status;
 406 }
 407
 408 static int
 409 ipq_receive_peer(struct ipq_peer_msg *pmsg,
 410                  unsigned char type, unsigned int len)
 411 {
 412         int status = 0;
 413
 414         if (len < sizeof(*pmsg))
 415                 return -EINVAL;
 416
 417         switch (type) {
 418         case IPQM_MODE:
 419                 status = ipq_set_mode(pmsg->msg.mode.value,
 420                                       pmsg->msg.mode.range);
 421                 break;
 422
 423         case IPQM_VERDICT:
 424                 if (pmsg->msg.verdict.value > NF_MAX_VERDICT)
 425                         status = -EINVAL;
 426                 else
 427                         status = ipq_set_verdict(&pmsg->msg.verdict,
 428                                                  len - sizeof(*pmsg));
 429                         break;
 430         default:
 431                 status = -EINVAL;
 432         }
 433         return status;
 434 }
 435
 436 static int
 437 dev_cmp(struct ipq_queue_entry *entry, unsigned long ifindex)
 438 {
 439         if (entry->info->indev)
 440                 if (entry->info->indev->ifindex == ifindex)
 441                         return 1;
 442
 443         if (entry->info->outdev)
 444                 if (entry->info->outdev->ifindex == ifindex)
 445                         return 1;
 446
 447         return 0;
 448 }
 449
 450 static void
 451 ipq_dev_drop(int ifindex)
 452 {
 453         struct ipq_queue_entry *entry;
 454
 455         while ((entry = ipq_find_dequeue_entry(dev_cmp, ifindex)) != NULL)
 456                 ipq_issue_verdict(entry, NF_DROP);
 457 }
 458
 459 #define RCV_SKB_FAIL(err) do { netlink_ack(skb, nlh, (err)); return; } while (0)
 460
 461 static inline void
 462 __ipq_rcv_skb(struct sk_buff *skb)
 463 {
 464         int status, type, pid, flags, nlmsglen, skblen;
 465         struct nlmsghdr *nlh;
 466
 467         skblen = skb->len;
 468         if (skblen < sizeof(*nlh))
 469                 return;
 470
 471         nlh = nlmsg_hdr(skb);
 472         nlmsglen = nlh->nlmsg_len;
 473         if (nlmsglen < sizeof(*nlh) || skblen < nlmsglen)
 474                 return;
 475
 476         pid = nlh->nlmsg_pid;
 477         flags = nlh->nlmsg_flags;
 478
 479         if(pid <= 0 || !(flags & NLM_F_REQUEST) || flags & NLM_F_MULTI)
 480                 RCV_SKB_FAIL(-EINVAL);
 481
 482         if (flags & MSG_TRUNC)
 483                 RCV_SKB_FAIL(-ECOMM);
 484
 485         type = nlh->nlmsg_type;
 486         if (type < NLMSG_NOOP || type >= IPQM_MAX)
 487                 RCV_SKB_FAIL(-EINVAL);
 488
 489         if (type <= IPQM_BASE)
 490                 return;
 491
 492         if (security_netlink_recv(skb, CAP_NET_ADMIN))
 493                 RCV_SKB_FAIL(-EPERM);
 494
 495         write_lock_bh(&queue_lock);
 496
 497         if (peer_pid) {
 498                 if (peer_pid != pid) {
 499                         write_unlock_bh(&queue_lock);
 500                         RCV_SKB_FAIL(-EBUSY);
 501                 }
 502         } else {
 503                 net_enable_timestamp();
 504                 peer_pid = pid;
 505         }
 506
 507         write_unlock_bh(&queue_lock);
 508
 509         status = ipq_receive_peer(NLMSG_DATA(nlh), type,
 510                                   nlmsglen - NLMSG_LENGTH(0));
 511         if (status < 0)
 512                 RCV_SKB_FAIL(status);
 513
 514         if (flags & NLM_F_ACK)
 515                 netlink_ack(skb, nlh, 0);
 516         return;
 517 }
 518
 519 static void
 520 ipq_rcv_skb(struct sk_buff *skb)
 521 {
 522         mutex_lock(&ipqnl_mutex);
 523         __ipq_rcv_skb(skb);
 524         mutex_unlock(&ipqnl_mutex);
 525 }
 526
 527 static int
 528 ipq_rcv_dev_event(struct notifier_block *this,
 529                   unsigned long event, void *ptr)
 530 {
 531         struct net_device *dev = ptr;
 532
 533         if (dev->nd_net != &init_net)
 534                 return NOTIFY_DONE;
 535
 536         /* Drop any packets associated with the downed device */
 537         if (event == NETDEV_DOWN)
 538                 ipq_dev_drop(dev->ifindex);
 539         return NOTIFY_DONE;
 540 }
 541
 542 static struct notifier_block ipq_dev_notifier = {
 543         .notifier_call  = ipq_rcv_dev_event,
 544 };
 545
 546 static int
 547 ipq_rcv_nl_event(struct notifier_block *this,
 548                  unsigned long event, void *ptr)
 549 {
 550         struct netlink_notify *n = ptr;
 551
 552         if (event == NETLINK_URELEASE &&
 553             n->protocol == NETLINK_IP6_FW && n->pid) {
 554                 write_lock_bh(&queue_lock);
 555                 if ((n->net == &init_net) && (n->pid == peer_pid))
 556                         __ipq_reset();
 557                 write_unlock_bh(&queue_lock);
 558         }
 559         return NOTIFY_DONE;
 560 }
 561
 562 static struct notifier_block ipq_nl_notifier = {
 563         .notifier_call  = ipq_rcv_nl_event,
 564 };
 565
 566 static struct ctl_table_header *ipq_sysctl_header;
 567
 568 static ctl_table ipq_table[] = {
 569         {
 570                 .ctl_name       = NET_IPQ_QMAX,
 571                 .procname       = NET_IPQ_QMAX_NAME,
 572                 .data           = &queue_maxlen,
 573                 .maxlen         = sizeof(queue_maxlen),
 574                 .mode           = 0644,
 575                 .proc_handler   = proc_dointvec
 576         },
 577         { .ctl_name = 0 }
 578 };
 579
 580 static ctl_table ipq_dir_table[] = {
 581         {
 582                 .ctl_name       = NET_IPV6,
 583                 .procname       = "ipv6",
 584                 .mode           = 0555,
 585                 .child          = ipq_table
 586         },
 587         { .ctl_name = 0 }
 588 };
 589
 590 static ctl_table ipq_root_table[] = {
 591         {
 592                 .ctl_name       = CTL_NET,
 593                 .procname       = "net",
 594                 .mode           = 0555,
 595                 .child          = ipq_dir_table
 596         },
 597         { .ctl_name = 0 }
 598 };
 599
 600 static int ip6_queue_show(struct seq_file *m, void *v)
 601 {
 602         read_lock_bh(&queue_lock);
 603
 604         seq_printf(m,
 605                       "Peer PID          : %d\n"
 606                       "Copy mode         : %hu\n"
 607                       "Copy range        : %u\n"
 608                       "Queue length      : %u\n"
 609                       "Queue max. length : %u\n"
 610                       "Queue dropped     : %u\n"
 611                       "Netfilter dropped : %u\n",
 612                       peer_pid,
 613                       copy_mode,
 614                       copy_range,
 615                       queue_total,
 616                       queue_maxlen,
 617                       queue_dropped,
 618                       queue_user_dropped);
 619
 620         read_unlock_bh(&queue_lock);
 621         return 0;
 622 }
 623
 624 static int ip6_queue_open(struct inode *inode, struct file *file)
 625 {
 626         return single_open(file, ip6_queue_show, NULL);
 627 }
 628
 629 static const struct file_operations ip6_queue_proc_fops = {
 630         .open           = ip6_queue_open,
 631         .read           = seq_read,
 632         .llseek         = seq_lseek,
 633         .release        = single_release,
 634         .owner          = THIS_MODULE,
 635 };
 636
 637 static struct nf_queue_handler nfqh = {
 638         .name   = "ip6_queue",
 639         .outfn  = &ipq_enqueue_packet,
 640 };
 641
 642 static int __init ip6_queue_init(void)
 643 {
 644         int status = -ENOMEM;
 645         struct proc_dir_entry *proc;
 646
 647         netlink_register_notifier(&ipq_nl_notifier);
 648         ipqnl = netlink_kernel_create(&init_net, NETLINK_IP6_FW, 0,
 649                                       ipq_rcv_skb, NULL, THIS_MODULE);
 650         if (ipqnl == NULL) {
 651                 printk(KERN_ERR "ip6_queue: failed to create netlink socket\n");
 652                 goto cleanup_netlink_notifier;
 653         }
 654
 655         proc = create_proc_entry(IPQ_PROC_FS_NAME, 0, init_net.proc_net);
 656         if (proc) {
 657                 proc->owner = THIS_MODULE;
 658                 proc->proc_fops = &ip6_queue_proc_fops;
 659         } else {
 660                 printk(KERN_ERR "ip6_queue: failed to create proc entry\n");
 661                 goto cleanup_ipqnl;
 662         }
 663
 664         register_netdevice_notifier(&ipq_dev_notifier);
 665         ipq_sysctl_header = register_sysctl_table(ipq_root_table);
 666
 667         status = nf_register_queue_handler(PF_INET6, &nfqh);
 668         if (status < 0) {
 669                 printk(KERN_ERR "ip6_queue: failed to register queue handler\n");
 670                 goto cleanup_sysctl;
 671         }
 672         return status;
 673
 674 cleanup_sysctl:
 675         unregister_sysctl_table(ipq_sysctl_header);
 676         unregister_netdevice_notifier(&ipq_dev_notifier);
 677         proc_net_remove(&init_net, IPQ_PROC_FS_NAME);
 678
 679 cleanup_ipqnl:
 680         sock_release(ipqnl->sk_socket);
 681         mutex_lock(&ipqnl_mutex);
 682         mutex_unlock(&ipqnl_mutex);
 683
 684 cleanup_netlink_notifier:
 685         netlink_unregister_notifier(&ipq_nl_notifier);
 686         return status;
 687 }
 688
 689 static void __exit ip6_queue_fini(void)
 690 {
 691         nf_unregister_queue_handlers(&nfqh);
 692         synchronize_net();
 693         ipq_flush(NF_DROP);
 694
 695         unregister_sysctl_table(ipq_sysctl_header);
 696         unregister_netdevice_notifier(&ipq_dev_notifier);
 697         proc_net_remove(&init_net, IPQ_PROC_FS_NAME);
 698
 699         sock_release(ipqnl->sk_socket);
 700         mutex_lock(&ipqnl_mutex);
 701         mutex_unlock(&ipqnl_mutex);
 702
 703         netlink_unregister_notifier(&ipq_nl_notifier);
 704 }
 705
 706 MODULE_DESCRIPTION("IPv6 packet queue handler");
 707 MODULE_LICENSE("GPL");
 708
 709 module_init(ip6_queue_init);
 710 module_exit(ip6_queue_fini);