net/ipv4/netfilter/ip_queue.c

   1 /*
   2  * This is a module which is used for queueing IPv4 packets and
   3  * communicating with userspace via netlink.
   4  *
   5  * (C) 2000-2002 James Morris <jmorris@intercode.com.au>
   6  * (C) 2003-2005 Netfilter Core Team <coreteam@netfilter.org>
   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 as
  10  * published by the Free Software Foundation.
  11  */
  12 #include <linux/module.h>
  13 #include <linux/skbuff.h>
  14 #include <linux/init.h>
  15 #include <linux/ip.h>
  16 #include <linux/notifier.h>
  17 #include <linux/netdevice.h>
  18 #include <linux/netfilter.h>
  19 #include <linux/netfilter_ipv4/ip_queue.h>
  20 #include <linux/netfilter_ipv4/ip_tables.h>
  21 #include <linux/netlink.h>
  22 #include <linux/spinlock.h>
  23 #include <linux/sysctl.h>
  24 #include <linux/proc_fs.h>
  25 #include <linux/seq_file.h>
  26 #include <linux/security.h>
  27 #include <linux/mutex.h>
  28 #include <net/net_namespace.h>
  29 #include <net/sock.h>
  30 #include <net/route.h>
  31 #include <net/netfilter/nf_queue.h>
  32 #include <net/ip.h>
  33
  34 #define IPQ_QMAX_DEFAULT 1024
  35 #define IPQ_PROC_FS_NAME "ip_queue"
  36 #define NET_IPQ_QMAX 2088
  37 #define NET_IPQ_QMAX_NAME "ip_queue_maxlen"
  38
  39 typedef int (*ipq_cmpfn)(struct nf_queue_entry *, unsigned long);
  40
  41 static unsigned char copy_mode __read_mostly = IPQ_COPY_NONE;
  42 static unsigned int queue_maxlen __read_mostly = IPQ_QMAX_DEFAULT;
  43 static DEFINE_RWLOCK(queue_lock);
  44 static int peer_pid __read_mostly;
  45 static unsigned int copy_range __read_mostly;
  46 static unsigned int queue_total;
  47 static unsigned int queue_dropped = 0;
  48 static unsigned int queue_user_dropped = 0;
  49 static struct sock *ipqnl __read_mostly;
  50 static LIST_HEAD(queue_list);
  51 static DEFINE_MUTEX(ipqnl_mutex);
  52
  53 static inline void
  54 __ipq_enqueue_entry(struct nf_queue_entry *entry)
  55 {
  56        list_add_tail(&entry->list, &queue_list);
  57        queue_total++;
  58 }
  59
  60 static inline int
  61 __ipq_set_mode(unsigned char mode, unsigned int range)
  62 {
  63         int status = 0;
  64
  65         switch(mode) {
  66         case IPQ_COPY_NONE:
  67         case IPQ_COPY_META:
  68                 copy_mode = mode;
  69                 copy_range = 0;
  70                 break;
  71
  72         case IPQ_COPY_PACKET:
  73                 copy_mode = mode;
  74                 copy_range = range;
  75                 if (copy_range > 0xFFFF)
  76                         copy_range = 0xFFFF;
  77                 break;
  78
  79         default:
  80                 status = -EINVAL;
  81
  82         }
  83         return status;
  84 }
  85
  86 static void __ipq_flush(ipq_cmpfn cmpfn, unsigned long data);
  87
  88 static inline void
  89 __ipq_reset(void)
  90 {
  91         peer_pid = 0;
  92         net_disable_timestamp();
  93         __ipq_set_mode(IPQ_COPY_NONE, 0);
  94         __ipq_flush(NULL, 0);
  95 }
  96
  97 static struct nf_queue_entry *
  98 ipq_find_dequeue_entry(unsigned long id)
  99 {
 100         struct nf_queue_entry *entry = NULL, *i;
 101
 102         write_lock_bh(&queue_lock);
 103
 104         list_for_each_entry(i, &queue_list, list) {
 105                 if ((unsigned long)i == id) {
 106                         entry = i;
 107                         break;
 108                 }
 109         }
 110
 111         if (entry) {
 112                 list_del(&entry->list);
 113                 queue_total--;
 114         }
 115
 116         write_unlock_bh(&queue_lock);
 117         return entry;
 118 }
 119
 120 static void
 121 __ipq_flush(ipq_cmpfn cmpfn, unsigned long data)
 122 {
 123         struct nf_queue_entry *entry, *next;
 124
 125         list_for_each_entry_safe(entry, next, &queue_list, list) {
 126                 if (!cmpfn || cmpfn(entry, data)) {
 127                         list_del(&entry->list);
 128                         queue_total--;
 129                         nf_reinject(entry, NF_DROP);
 130                 }
 131         }
 132 }
 133
 134 static void
 135 ipq_flush(ipq_cmpfn cmpfn, unsigned long data)
 136 {
 137         write_lock_bh(&queue_lock);
 138         __ipq_flush(cmpfn, data);
 139         write_unlock_bh(&queue_lock);
 140 }
 141
 142 static struct sk_buff *
 143 ipq_build_packet_message(struct nf_queue_entry *entry, int *errp)
 144 {
 145         sk_buff_data_t old_tail;
 146         size_t size = 0;
 147         size_t data_len = 0;
 148         struct sk_buff *skb;
 149         struct ipq_packet_msg *pmsg;
 150         struct nlmsghdr *nlh;
 151         struct timeval tv;
 152
 153         read_lock_bh(&queue_lock);
 154
 155         switch (copy_mode) {
 156         case IPQ_COPY_META:
 157         case IPQ_COPY_NONE:
 158                 size = NLMSG_SPACE(sizeof(*pmsg));
 159                 data_len = 0;
 160                 break;
 161
 162         case IPQ_COPY_PACKET:
 163                 if ((entry->skb->ip_summed == CHECKSUM_PARTIAL ||
 164                      entry->skb->ip_summed == CHECKSUM_COMPLETE) &&
 165                     (*errp = skb_checksum_help(entry->skb))) {
 166                         read_unlock_bh(&queue_lock);
 167                         return NULL;
 168                 }
 169                 if (copy_range == 0 || copy_range > entry->skb->len)
 170                         data_len = entry->skb->len;
 171                 else
 172                         data_len = copy_range;
 173
 174                 size = NLMSG_SPACE(sizeof(*pmsg) + data_len);
 175                 break;
 176
 177         default:
 178                 *errp = -EINVAL;
 179                 read_unlock_bh(&queue_lock);
 180                 return NULL;
 181         }
 182
 183         read_unlock_bh(&queue_lock);
 184
 185         skb = alloc_skb(size, GFP_ATOMIC);
 186         if (!skb)
 187                 goto nlmsg_failure;
 188
 189         old_tail = skb->tail;
 190         nlh = NLMSG_PUT(skb, 0, 0, IPQM_PACKET, size - sizeof(*nlh));
 191         pmsg = NLMSG_DATA(nlh);
 192         memset(pmsg, 0, sizeof(*pmsg));
 193
 194         pmsg->packet_id       = (unsigned long )entry;
 195         pmsg->data_len        = data_len;
 196         tv = ktime_to_timeval(entry->skb->tstamp);
 197         pmsg->timestamp_sec   = tv.tv_sec;
 198         pmsg->timestamp_usec  = tv.tv_usec;
 199         pmsg->mark            = entry->skb->mark;
 200         pmsg->hook            = entry->hook;
 201         pmsg->hw_protocol     = entry->skb->protocol;
 202
 203         if (entry->indev)
 204                 strcpy(pmsg->indev_name, entry->indev->name);
 205         else
 206                 pmsg->indev_name[0] = '\0';
 207
 208         if (entry->outdev)
 209                 strcpy(pmsg->outdev_name, entry->outdev->name);
 210         else
 211                 pmsg->outdev_name[0] = '\0';
 212
 213         if (entry->indev && entry->skb->dev) {
 214                 pmsg->hw_type = entry->skb->dev->type;
 215                 pmsg->hw_addrlen = dev_parse_header(entry->skb,
 216                                                     pmsg->hw_addr);
 217         }
 218
 219         if (data_len)
 220                 if (skb_copy_bits(entry->skb, 0, pmsg->payload, data_len))
 221                         BUG();
 222
 223         nlh->nlmsg_len = skb->tail - old_tail;
 224         return skb;
 225
 226 nlmsg_failure:
 227         if (skb)
 228                 kfree_skb(skb);
 229         *errp = -EINVAL;
 230         printk(KERN_ERR "ip_queue: error creating packet message\n");
 231         return NULL;
 232 }
 233
 234 static int
 235 ipq_enqueue_packet(struct nf_queue_entry *entry, unsigned int queuenum)
 236 {
 237         int status = -EINVAL;
 238         struct sk_buff *nskb;
 239
 240         if (copy_mode == IPQ_COPY_NONE)
 241                 return -EAGAIN;
 242
 243         nskb = ipq_build_packet_message(entry, &status);
 244         if (nskb == NULL)
 245                 return status;
 246
 247         write_lock_bh(&queue_lock);
 248
 249         if (!peer_pid)
 250                 goto err_out_free_nskb;
 251
 252         if (queue_total >= queue_maxlen) {
 253                 queue_dropped++;
 254                 status = -ENOSPC;
 255                 if (net_ratelimit())
 256                           printk (KERN_WARNING "ip_queue: full at %d entries, "
 257                                   "dropping packets(s). Dropped: %d\n", queue_total,
 258                                   queue_dropped);
 259                 goto err_out_free_nskb;
 260         }
 261
 262         /* netlink_unicast will either free the nskb or attach it to a socket */
 263         status = netlink_unicast(ipqnl, nskb, peer_pid, MSG_DONTWAIT);
 264         if (status < 0) {
 265                 queue_user_dropped++;
 266                 goto err_out_unlock;
 267         }
 268
 269         __ipq_enqueue_entry(entry);
 270
 271         write_unlock_bh(&queue_lock);
 272         return status;
 273
 274 err_out_free_nskb:
 275         kfree_skb(nskb);
 276
 277 err_out_unlock:
 278         write_unlock_bh(&queue_lock);
 279         return status;
 280 }
 281
 282 static int
 283 ipq_mangle_ipv4(ipq_verdict_msg_t *v, struct nf_queue_entry *e)
 284 {
 285         int diff;
 286 <<<<<<< HEAD:net/ipv4/netfilter/ip_queue.c
 287         int err;
 288 =======
 289 >>>>>>> 264e3e889d86e552b4191d69bb60f4f3b383135a:net/ipv4/netfilter/ip_queue.c
 290         struct iphdr *user_iph = (struct iphdr *)v->payload;
 291 <<<<<<< HEAD:net/ipv4/netfilter/ip_queue.c
 292 =======
 293         struct sk_buff *nskb;
 294 >>>>>>> 264e3e889d86e552b4191d69bb60f4f3b383135a:net/ipv4/netfilter/ip_queue.c
 295
 296         if (v->data_len < sizeof(*user_iph))
 297                 return 0;
 298         diff = v->data_len - e->skb->len;
 299         if (diff < 0) {
 300                 if (pskb_trim(e->skb, v->data_len))
 301                         return -ENOMEM;
 302         } else if (diff > 0) {
 303                 if (v->data_len > 0xFFFF)
 304                         return -EINVAL;
 305                 if (diff > skb_tailroom(e->skb)) {
 306 <<<<<<< HEAD:net/ipv4/netfilter/ip_queue.c
 307                         err = pskb_expand_head(e->skb, 0,
 308 =======
 309                         nskb = skb_copy_expand(e->skb, 0,
 310 >>>>>>> 264e3e889d86e552b4191d69bb60f4f3b383135a:net/ipv4/netfilter/ip_queue.c
 311                                                diff - skb_tailroom(e->skb),
 312                                                GFP_ATOMIC);
 313 <<<<<<< HEAD:net/ipv4/netfilter/ip_queue.c
 314                         if (err) {
 315 =======
 316                         if (!nskb) {
 317 >>>>>>> 264e3e889d86e552b4191d69bb60f4f3b383135a:net/ipv4/netfilter/ip_queue.c
 318                                 printk(KERN_WARNING "ip_queue: error "
 319 <<<<<<< HEAD:net/ipv4/netfilter/ip_queue.c
 320                                       "in mangle, dropping packet: %d\n", -err);
 321                                 return err;
 322 =======
 323                                       "in mangle, dropping packet\n");
 324                                 return -ENOMEM;
 325 >>>>>>> 264e3e889d86e552b4191d69bb60f4f3b383135a:net/ipv4/netfilter/ip_queue.c
 326                         }
 327 <<<<<<< HEAD:net/ipv4/netfilter/ip_queue.c
 328 =======
 329                         kfree_skb(e->skb);
 330                         e->skb = nskb;
 331 >>>>>>> 264e3e889d86e552b4191d69bb60f4f3b383135a:net/ipv4/netfilter/ip_queue.c
 332                 }
 333                 skb_put(e->skb, diff);
 334         }
 335         if (!skb_make_writable(e->skb, v->data_len))
 336                 return -ENOMEM;
 337         skb_copy_to_linear_data(e->skb, v->payload, v->data_len);
 338         e->skb->ip_summed = CHECKSUM_NONE;
 339
 340         return 0;
 341 }
 342
 343 static int
 344 ipq_set_verdict(struct ipq_verdict_msg *vmsg, unsigned int len)
 345 {
 346         struct nf_queue_entry *entry;
 347
 348         if (vmsg->value > NF_MAX_VERDICT)
 349                 return -EINVAL;
 350
 351         entry = ipq_find_dequeue_entry(vmsg->id);
 352         if (entry == NULL)
 353                 return -ENOENT;
 354         else {
 355                 int verdict = vmsg->value;
 356
 357                 if (vmsg->data_len && vmsg->data_len == len)
 358                         if (ipq_mangle_ipv4(vmsg, entry) < 0)
 359                                 verdict = NF_DROP;
 360
 361                 nf_reinject(entry, verdict);
 362                 return 0;
 363         }
 364 }
 365
 366 static int
 367 ipq_set_mode(unsigned char mode, unsigned int range)
 368 {
 369         int status;
 370
 371         write_lock_bh(&queue_lock);
 372         status = __ipq_set_mode(mode, range);
 373         write_unlock_bh(&queue_lock);
 374         return status;
 375 }
 376
 377 static int
 378 ipq_receive_peer(struct ipq_peer_msg *pmsg,
 379                  unsigned char type, unsigned int len)
 380 {
 381         int status = 0;
 382
 383         if (len < sizeof(*pmsg))
 384                 return -EINVAL;
 385
 386         switch (type) {
 387         case IPQM_MODE:
 388                 status = ipq_set_mode(pmsg->msg.mode.value,
 389                                       pmsg->msg.mode.range);
 390                 break;
 391
 392         case IPQM_VERDICT:
 393                 if (pmsg->msg.verdict.value > NF_MAX_VERDICT)
 394                         status = -EINVAL;
 395                 else
 396                         status = ipq_set_verdict(&pmsg->msg.verdict,
 397                                                  len - sizeof(*pmsg));
 398                         break;
 399         default:
 400                 status = -EINVAL;
 401         }
 402         return status;
 403 }
 404
 405 static int
 406 dev_cmp(struct nf_queue_entry *entry, unsigned long ifindex)
 407 {
 408         if (entry->indev)
 409                 if (entry->indev->ifindex == ifindex)
 410                         return 1;
 411         if (entry->outdev)
 412                 if (entry->outdev->ifindex == ifindex)
 413                         return 1;
 414 #ifdef CONFIG_BRIDGE_NETFILTER
 415         if (entry->skb->nf_bridge) {
 416                 if (entry->skb->nf_bridge->physindev &&
 417                     entry->skb->nf_bridge->physindev->ifindex == ifindex)
 418                         return 1;
 419                 if (entry->skb->nf_bridge->physoutdev &&
 420                     entry->skb->nf_bridge->physoutdev->ifindex == ifindex)
 421                         return 1;
 422         }
 423 #endif
 424         return 0;
 425 }
 426
 427 static void
 428 ipq_dev_drop(int ifindex)
 429 {
 430         ipq_flush(dev_cmp, ifindex);
 431 }
 432
 433 #define RCV_SKB_FAIL(err) do { netlink_ack(skb, nlh, (err)); return; } while (0)
 434
 435 static inline void
 436 __ipq_rcv_skb(struct sk_buff *skb)
 437 {
 438         int status, type, pid, flags, nlmsglen, skblen;
 439         struct nlmsghdr *nlh;
 440
 441         skblen = skb->len;
 442         if (skblen < sizeof(*nlh))
 443                 return;
 444
 445         nlh = nlmsg_hdr(skb);
 446         nlmsglen = nlh->nlmsg_len;
 447         if (nlmsglen < sizeof(*nlh) || skblen < nlmsglen)
 448                 return;
 449
 450         pid = nlh->nlmsg_pid;
 451         flags = nlh->nlmsg_flags;
 452
 453         if(pid <= 0 || !(flags & NLM_F_REQUEST) || flags & NLM_F_MULTI)
 454                 RCV_SKB_FAIL(-EINVAL);
 455
 456         if (flags & MSG_TRUNC)
 457                 RCV_SKB_FAIL(-ECOMM);
 458
 459         type = nlh->nlmsg_type;
 460         if (type < NLMSG_NOOP || type >= IPQM_MAX)
 461                 RCV_SKB_FAIL(-EINVAL);
 462
 463         if (type <= IPQM_BASE)
 464                 return;
 465
 466         if (security_netlink_recv(skb, CAP_NET_ADMIN))
 467                 RCV_SKB_FAIL(-EPERM);
 468
 469         write_lock_bh(&queue_lock);
 470
 471         if (peer_pid) {
 472                 if (peer_pid != pid) {
 473                         write_unlock_bh(&queue_lock);
 474                         RCV_SKB_FAIL(-EBUSY);
 475                 }
 476         } else {
 477                 net_enable_timestamp();
 478                 peer_pid = pid;
 479         }
 480
 481         write_unlock_bh(&queue_lock);
 482
 483         status = ipq_receive_peer(NLMSG_DATA(nlh), type,
 484                                   nlmsglen - NLMSG_LENGTH(0));
 485         if (status < 0)
 486                 RCV_SKB_FAIL(status);
 487
 488         if (flags & NLM_F_ACK)
 489                 netlink_ack(skb, nlh, 0);
 490         return;
 491 }
 492
 493 static void
 494 ipq_rcv_skb(struct sk_buff *skb)
 495 {
 496         mutex_lock(&ipqnl_mutex);
 497         __ipq_rcv_skb(skb);
 498         mutex_unlock(&ipqnl_mutex);
 499 }
 500
 501 static int
 502 ipq_rcv_dev_event(struct notifier_block *this,
 503                   unsigned long event, void *ptr)
 504 {
 505         struct net_device *dev = ptr;
 506
 507         if (dev->nd_net != &init_net)
 508                 return NOTIFY_DONE;
 509
 510         /* Drop any packets associated with the downed device */
 511         if (event == NETDEV_DOWN)
 512                 ipq_dev_drop(dev->ifindex);
 513         return NOTIFY_DONE;
 514 }
 515
 516 static struct notifier_block ipq_dev_notifier = {
 517         .notifier_call  = ipq_rcv_dev_event,
 518 };
 519
 520 static int
 521 ipq_rcv_nl_event(struct notifier_block *this,
 522                  unsigned long event, void *ptr)
 523 {
 524         struct netlink_notify *n = ptr;
 525
 526         if (event == NETLINK_URELEASE &&
 527             n->protocol == NETLINK_FIREWALL && n->pid) {
 528                 write_lock_bh(&queue_lock);
 529                 if ((n->net == &init_net) && (n->pid == peer_pid))
 530                         __ipq_reset();
 531                 write_unlock_bh(&queue_lock);
 532         }
 533         return NOTIFY_DONE;
 534 }
 535
 536 static struct notifier_block ipq_nl_notifier = {
 537         .notifier_call  = ipq_rcv_nl_event,
 538 };
 539
 540 #ifdef CONFIG_SYSCTL
 541 static struct ctl_table_header *ipq_sysctl_header;
 542
 543 static ctl_table ipq_table[] = {
 544         {
 545                 .ctl_name       = NET_IPQ_QMAX,
 546                 .procname       = NET_IPQ_QMAX_NAME,
 547                 .data           = &queue_maxlen,
 548                 .maxlen         = sizeof(queue_maxlen),
 549                 .mode           = 0644,
 550                 .proc_handler   = proc_dointvec
 551         },
 552         { .ctl_name = 0 }
 553 };
 554 #endif
 555
 556 #ifdef CONFIG_PROC_FS
 557 static int ip_queue_show(struct seq_file *m, void *v)
 558 {
 559         read_lock_bh(&queue_lock);
 560
 561         seq_printf(m,
 562                       "Peer PID          : %d\n"
 563                       "Copy mode         : %hu\n"
 564                       "Copy range        : %u\n"
 565                       "Queue length      : %u\n"
 566                       "Queue max. length : %u\n"
 567                       "Queue dropped     : %u\n"
 568                       "Netlink dropped   : %u\n",
 569                       peer_pid,
 570                       copy_mode,
 571                       copy_range,
 572                       queue_total,
 573                       queue_maxlen,
 574                       queue_dropped,
 575                       queue_user_dropped);
 576
 577         read_unlock_bh(&queue_lock);
 578         return 0;
 579 }
 580
 581 static int ip_queue_open(struct inode *inode, struct file *file)
 582 {
 583         return single_open(file, ip_queue_show, NULL);
 584 }
 585
 586 static const struct file_operations ip_queue_proc_fops = {
 587         .open           = ip_queue_open,
 588         .read           = seq_read,
 589         .llseek         = seq_lseek,
 590         .release        = single_release,
 591         .owner          = THIS_MODULE,
 592 };
 593 #endif
 594
 595 static const struct nf_queue_handler nfqh = {
 596         .name   = "ip_queue",
 597         .outfn  = &ipq_enqueue_packet,
 598 };
 599
 600 static int __init ip_queue_init(void)
 601 {
 602         int status = -ENOMEM;
 603         struct proc_dir_entry *proc __maybe_unused;
 604
 605         netlink_register_notifier(&ipq_nl_notifier);
 606         ipqnl = netlink_kernel_create(&init_net, NETLINK_FIREWALL, 0,
 607                                       ipq_rcv_skb, NULL, THIS_MODULE);
 608         if (ipqnl == NULL) {
 609                 printk(KERN_ERR "ip_queue: failed to create netlink socket\n");
 610                 goto cleanup_netlink_notifier;
 611         }
 612
 613 #ifdef CONFIG_PROC_FS
 614         proc = create_proc_entry(IPQ_PROC_FS_NAME, 0, init_net.proc_net);
 615         if (proc) {
 616                 proc->owner = THIS_MODULE;
 617                 proc->proc_fops = &ip_queue_proc_fops;
 618         } else {
 619                 printk(KERN_ERR "ip_queue: failed to create proc entry\n");
 620                 goto cleanup_ipqnl;
 621         }
 622 #endif
 623         register_netdevice_notifier(&ipq_dev_notifier);
 624 #ifdef CONFIG_SYSCTL
 625         ipq_sysctl_header = register_sysctl_paths(net_ipv4_ctl_path, ipq_table);
 626 #endif
 627         status = nf_register_queue_handler(PF_INET, &nfqh);
 628         if (status < 0) {
 629                 printk(KERN_ERR "ip_queue: failed to register queue handler\n");
 630                 goto cleanup_sysctl;
 631         }
 632         return status;
 633
 634 cleanup_sysctl:
 635 #ifdef CONFIG_SYSCTL
 636         unregister_sysctl_table(ipq_sysctl_header);
 637 #endif
 638         unregister_netdevice_notifier(&ipq_dev_notifier);
 639         proc_net_remove(&init_net, IPQ_PROC_FS_NAME);
 640 cleanup_ipqnl: __maybe_unused
 641         netlink_kernel_release(ipqnl);
 642         mutex_lock(&ipqnl_mutex);
 643         mutex_unlock(&ipqnl_mutex);
 644
 645 cleanup_netlink_notifier:
 646         netlink_unregister_notifier(&ipq_nl_notifier);
 647         return status;
 648 }
 649
 650 static void __exit ip_queue_fini(void)
 651 {
 652         nf_unregister_queue_handlers(&nfqh);
 653         synchronize_net();
 654         ipq_flush(NULL, 0);
 655
 656 #ifdef CONFIG_SYSCTL
 657         unregister_sysctl_table(ipq_sysctl_header);
 658 #endif
 659         unregister_netdevice_notifier(&ipq_dev_notifier);
 660         proc_net_remove(&init_net, IPQ_PROC_FS_NAME);
 661
 662         netlink_kernel_release(ipqnl);
 663         mutex_lock(&ipqnl_mutex);
 664         mutex_unlock(&ipqnl_mutex);
 665
 666         netlink_unregister_notifier(&ipq_nl_notifier);
 667 }
 668
 669 MODULE_DESCRIPTION("IPv4 packet queue handler");
 670 MODULE_AUTHOR("James Morris <jmorris@intercode.com.au>");
 671 MODULE_LICENSE("GPL");
 672
 673 module_init(ip_queue_init);
 674 module_exit(ip_queue_fini);