net/ipv6/netfilter/nf_conntrack_reasm.c

   1 /*
   2  * IPv6 fragment reassembly for connection tracking
   3  *
   4  * Copyright (C)2004 USAGI/WIDE Project
   5  *
   6  * Author:
   7  *      Yasuyuki Kozakai @USAGI <yasuyuki.kozakai@toshiba.co.jp>
   8  *
   9  * Based on: net/ipv6/reassembly.c
  10  *
  11  * This program is free software; you can redistribute it and/or
  12  * modify it under the terms of the GNU General Public License
  13  * as published by the Free Software Foundation; either version
  14  * 2 of the License, or (at your option) any later version.
  15  */
  16
  17 #define pr_fmt(fmt) "IPv6-nf: " fmt
  18
  19 #include <linux/errno.h>
  20 #include <linux/types.h>
  21 #include <linux/string.h>
  22 #include <linux/socket.h>
  23 #include <linux/sockios.h>
  24 #include <linux/jiffies.h>
  25 #include <linux/net.h>
  26 #include <linux/list.h>
  27 #include <linux/netdevice.h>
  28 #include <linux/in6.h>
  29 #include <linux/ipv6.h>
  30 #include <linux/icmpv6.h>
  31 #include <linux/random.h>
  32 #include <linux/slab.h>
  33
  34 #include <net/sock.h>
  35 #include <net/snmp.h>
  36 #include <net/inet_frag.h>
  37
  38 #include <net/ipv6.h>
  39 #include <net/protocol.h>
  40 #include <net/transp_v6.h>
  41 #include <net/rawv6.h>
  42 #include <net/ndisc.h>
  43 #include <net/addrconf.h>
  44 #include <net/inet_ecn.h>
  45 #include <net/netfilter/ipv6/nf_conntrack_ipv6.h>
  46 #include <linux/sysctl.h>
  47 #include <linux/netfilter.h>
  48 #include <linux/netfilter_ipv6.h>
  49 #include <linux/kernel.h>
  50 #include <linux/module.h>
  51 #include <net/netfilter/ipv6/nf_defrag_ipv6.h>
  52
  53
  54 struct nf_ct_frag6_skb_cb
  55 {
  56         struct inet6_skb_parm   h;
  57         int                     offset;
  58         struct sk_buff          *orig;
  59 };
  60
  61 #define NFCT_FRAG6_CB(skb)      ((struct nf_ct_frag6_skb_cb*)((skb)->cb))
  62
  63 static struct inet_frags nf_frags;
  64
  65 #ifdef CONFIG_SYSCTL
  66 static struct ctl_table nf_ct_frag6_sysctl_table[] = {
  67         {
  68                 .procname       = "nf_conntrack_frag6_timeout",
  69                 .data           = &init_net.nf_frag.frags.timeout,
  70                 .maxlen         = sizeof(unsigned int),
  71                 .mode           = 0644,
  72                 .proc_handler   = proc_dointvec_jiffies,
  73         },
  74         {
  75                 .procname       = "nf_conntrack_frag6_low_thresh",
  76                 .data           = &init_net.nf_frag.frags.low_thresh,
  77                 .maxlen         = sizeof(unsigned int),
  78                 .mode           = 0644,
  79                 .proc_handler   = proc_dointvec,
  80         },
  81         {
  82                 .procname       = "nf_conntrack_frag6_high_thresh",
  83                 .data           = &init_net.nf_frag.frags.high_thresh,
  84                 .maxlen         = sizeof(unsigned int),
  85                 .mode           = 0644,
  86                 .proc_handler   = proc_dointvec,
  87         },
  88         { }
  89 };
  90
  91 static int nf_ct_frag6_sysctl_register(struct net *net)
  92 {
  93         struct ctl_table *table;
  94         struct ctl_table_header *hdr;
  95
  96         table = nf_ct_frag6_sysctl_table;
  97         if (!net_eq(net, &init_net)) {
  98                 table = kmemdup(table, sizeof(nf_ct_frag6_sysctl_table),
  99                                 GFP_KERNEL);
 100                 if (table == NULL)
 101                         goto err_alloc;
 102
 103                 table[0].data = &net->nf_frag.frags.timeout;
 104                 table[1].data = &net->nf_frag.frags.low_thresh;
 105                 table[2].data = &net->nf_frag.frags.high_thresh;
 106         }
 107
 108         hdr = register_net_sysctl(net, "net/netfilter", table);
 109         if (hdr == NULL)
 110                 goto err_reg;
 111
 112         net->nf_frag.sysctl.frags_hdr = hdr;
 113         return 0;
 114
 115 err_reg:
 116         if (!net_eq(net, &init_net))
 117                 kfree(table);
 118 err_alloc:
 119         return -ENOMEM;
 120 }
 121
 122 static void __net_exit nf_ct_frags6_sysctl_unregister(struct net *net)
 123 {
 124         struct ctl_table *table;
 125
 126         table = net->nf_frag.sysctl.frags_hdr->ctl_table_arg;
 127         unregister_net_sysctl_table(net->nf_frag.sysctl.frags_hdr);
 128         if (!net_eq(net, &init_net))
 129                 kfree(table);
 130 }
 131
 132 #else
 133 static int nf_ct_frag6_sysctl_register(struct net *net)
 134 {
 135         return 0;
 136 }
 137 static void __net_exit nf_ct_frags6_sysctl_unregister(struct net *net)
 138 {
 139 }
 140 #endif
 141
 142 static inline u8 ip6_frag_ecn(const struct ipv6hdr *ipv6h)
 143 {
 144         return 1 << (ipv6_get_dsfield(ipv6h) & INET_ECN_MASK);
 145 }
 146
 147 static unsigned int nf_hashfn(struct inet_frag_queue *q)
 148 {
 149         const struct frag_queue *nq;
 150
 151         nq = container_of(q, struct frag_queue, q);
 152         return inet6_hash_frag(nq->id, &nq->saddr, &nq->daddr, nf_frags.rnd);
 153 }
 154
 155 static void nf_skb_free(struct sk_buff *skb)
 156 {
 157         if (NFCT_FRAG6_CB(skb)->orig)
 158                 kfree_skb(NFCT_FRAG6_CB(skb)->orig);
 159 }
 160
 161 static void nf_ct_frag6_expire(unsigned long data)
 162 {
 163         struct frag_queue *fq;
 164         struct net *net;
 165
 166         fq = container_of((struct inet_frag_queue *)data, struct frag_queue, q);
 167         net = container_of(fq->q.net, struct net, nf_frag.frags);
 168
 169         ip6_expire_frag_queue(net, fq, &nf_frags);
 170 }
 171
 172 /* Creation primitives. */
 173 static inline struct frag_queue *fq_find(struct net *net, __be32 id,
 174                                          u32 user, struct in6_addr *src,
 175                                          struct in6_addr *dst, u8 ecn)
 176 {
 177         struct inet_frag_queue *q;
 178         struct ip6_create_arg arg;
 179         unsigned int hash;
 180
 181         arg.id = id;
 182         arg.user = user;
 183         arg.src = src;
 184         arg.dst = dst;
 185         arg.ecn = ecn;
 186
 187         read_lock_bh(&nf_frags.lock);
 188         hash = inet6_hash_frag(id, src, dst, nf_frags.rnd);
 189
 190         q = inet_frag_find(&net->nf_frag.frags, &nf_frags, &arg, hash);
 191         local_bh_enable();
 192         if (IS_ERR_OR_NULL(q)) {
 193                 inet_frag_maybe_warn_overflow(q, pr_fmt());
 194                 return NULL;
 195         }
 196         return container_of(q, struct frag_queue, q);
 197 }
 198
 199
 200 static int nf_ct_frag6_queue(struct frag_queue *fq, struct sk_buff *skb,
 201                              const struct frag_hdr *fhdr, int nhoff)
 202 {
 203         struct sk_buff *prev, *next;
 204         unsigned int payload_len;
 205         int offset, end;
 206         u8 ecn;
 207
 208         if (fq->q.last_in & INET_FRAG_COMPLETE) {
 209                 pr_debug("Already completed\n");
 210                 goto err;
 211         }
 212
 213         payload_len = ntohs(ipv6_hdr(skb)->payload_len);
 214
 215         offset = ntohs(fhdr->frag_off) & ~0x7;
 216         end = offset + (payload_len -
 217                         ((u8 *)(fhdr + 1) - (u8 *)(ipv6_hdr(skb) + 1)));
 218
 219         if ((unsigned int)end > IPV6_MAXPLEN) {
 220                 pr_debug("offset is too large.\n");
 221                 return -1;
 222         }
 223
 224         ecn = ip6_frag_ecn(ipv6_hdr(skb));
 225
 226         if (skb->ip_summed == CHECKSUM_COMPLETE) {
 227                 const unsigned char *nh = skb_network_header(skb);
 228                 skb->csum = csum_sub(skb->csum,
 229                                      csum_partial(nh, (u8 *)(fhdr + 1) - nh,
 230                                                   0));
 231         }
 232
 233         /* Is this the final fragment? */
 234         if (!(fhdr->frag_off & htons(IP6_MF))) {
 235                 /* If we already have some bits beyond end
 236                  * or have different end, the segment is corrupted.
 237                  */
 238                 if (end < fq->q.len ||
 239                     ((fq->q.last_in & INET_FRAG_LAST_IN) && end != fq->q.len)) {
 240                         pr_debug("already received last fragment\n");
 241                         goto err;
 242                 }
 243                 fq->q.last_in |= INET_FRAG_LAST_IN;
 244                 fq->q.len = end;
 245         } else {
 246                 /* Check if the fragment is rounded to 8 bytes.
 247                  * Required by the RFC.
 248                  */
 249                 if (end & 0x7) {
 250                         /* RFC2460 says always send parameter problem in
 251                          * this case. -DaveM
 252                          */
 253                         pr_debug("end of fragment not rounded to 8 bytes.\n");
 254                         return -1;
 255                 }
 256                 if (end > fq->q.len) {
 257                         /* Some bits beyond end -> corruption. */
 258                         if (fq->q.last_in & INET_FRAG_LAST_IN) {
 259                                 pr_debug("last packet already reached.\n");
 260                                 goto err;
 261                         }
 262                         fq->q.len = end;
 263                 }
 264         }
 265
 266         if (end == offset)
 267                 goto err;
 268
 269         /* Point into the IP datagram 'data' part. */
 270         if (!pskb_pull(skb, (u8 *) (fhdr + 1) - skb->data)) {
 271                 pr_debug("queue: message is too short.\n");
 272                 goto err;
 273         }
 274         if (pskb_trim_rcsum(skb, end - offset)) {
 275                 pr_debug("Can't trim\n");
 276                 goto err;
 277         }
 278
 279         /* Find out which fragments are in front and at the back of us
 280          * in the chain of fragments so far.  We must know where to put
 281          * this fragment, right?
 282          */
 283         prev = fq->q.fragments_tail;
 284         if (!prev || NFCT_FRAG6_CB(prev)->offset < offset) {
 285                 next = NULL;
 286                 goto found;
 287         }
 288         prev = NULL;
 289         for (next = fq->q.fragments; next != NULL; next = next->next) {
 290                 if (NFCT_FRAG6_CB(next)->offset >= offset)
 291                         break;  /* bingo! */
 292                 prev = next;
 293         }
 294
 295 found:
 296         /* RFC5722, Section 4:
 297          *                                  When reassembling an IPv6 datagram, if
 298          *   one or more its constituent fragments is determined to be an
 299          *   overlapping fragment, the entire datagram (and any constituent
 300          *   fragments, including those not yet received) MUST be silently
 301          *   discarded.
 302          */
 303
 304         /* Check for overlap with preceding fragment. */
 305         if (prev &&
 306             (NFCT_FRAG6_CB(prev)->offset + prev->len) > offset)
 307                 goto discard_fq;
 308
 309         /* Look for overlap with succeeding segment. */
 310         if (next && NFCT_FRAG6_CB(next)->offset < end)
 311                 goto discard_fq;
 312
 313         NFCT_FRAG6_CB(skb)->offset = offset;
 314
 315         /* Insert this fragment in the chain of fragments. */
 316         skb->next = next;
 317         if (!next)
 318                 fq->q.fragments_tail = skb;
 319         if (prev)
 320                 prev->next = skb;
 321         else
 322                 fq->q.fragments = skb;
 323
 324         if (skb->dev) {
 325                 fq->iif = skb->dev->ifindex;
 326                 skb->dev = NULL;
 327         }
 328         fq->q.stamp = skb->tstamp;
 329         fq->q.meat += skb->len;
 330         fq->ecn |= ecn;
 331         if (payload_len > fq->q.max_size)
 332                 fq->q.max_size = payload_len;
 333         add_frag_mem_limit(&fq->q, skb->truesize);
 334
 335         /* The first fragment.
 336          * nhoffset is obtained from the first fragment, of course.
 337          */
 338         if (offset == 0) {
 339                 fq->nhoffset = nhoff;
 340                 fq->q.last_in |= INET_FRAG_FIRST_IN;
 341         }
 342
 343         inet_frag_lru_move(&fq->q);
 344         return 0;
 345
 346 discard_fq:
 347         inet_frag_kill(&fq->q, &nf_frags);
 348 err:
 349         return -1;
 350 }
 351
 352 /*
 353  *      Check if this packet is complete.
 354  *      Returns NULL on failure by any reason, and pointer
 355  *      to current nexthdr field in reassembled frame.
 356  *
 357  *      It is called with locked fq, and caller must check that
 358  *      queue is eligible for reassembly i.e. it is not COMPLETE,
 359  *      the last and the first frames arrived and all the bits are here.
 360  */
 361 static struct sk_buff *
 362 nf_ct_frag6_reasm(struct frag_queue *fq, struct net_device *dev)
 363 {
 364         struct sk_buff *fp, *op, *head = fq->q.fragments;
 365         int    payload_len;
 366         u8 ecn;
 367
 368         inet_frag_kill(&fq->q, &nf_frags);
 369
 370         WARN_ON(head == NULL);
 371         WARN_ON(NFCT_FRAG6_CB(head)->offset != 0);
 372
 373         ecn = ip_frag_ecn_table[fq->ecn];
 374         if (unlikely(ecn == 0xff))
 375                 goto out_fail;
 376
 377         /* Unfragmented part is taken from the first segment. */
 378         payload_len = ((head->data - skb_network_header(head)) -
 379                        sizeof(struct ipv6hdr) + fq->q.len -
 380                        sizeof(struct frag_hdr));
 381         if (payload_len > IPV6_MAXPLEN) {
 382                 pr_debug("payload len is too large.\n");
 383                 goto out_oversize;
 384         }
 385
 386         /* Head of list must not be cloned. */
 387         if (skb_unclone(head, GFP_ATOMIC)) {
 388                 pr_debug("skb is cloned but can't expand head");
 389                 goto out_oom;
 390         }
 391
 392         /* If the first fragment is fragmented itself, we split
 393          * it to two chunks: the first with data and paged part
 394          * and the second, holding only fragments. */
 395         if (skb_has_frag_list(head)) {
 396                 struct sk_buff *clone;
 397                 int i, plen = 0;
 398
 399                 clone = alloc_skb(0, GFP_ATOMIC);
 400                 if (clone == NULL)
 401                         goto out_oom;
 402
 403                 clone->next = head->next;
 404                 head->next = clone;
 405                 skb_shinfo(clone)->frag_list = skb_shinfo(head)->frag_list;
 406                 skb_frag_list_init(head);
 407                 for (i = 0; i < skb_shinfo(head)->nr_frags; i++)
 408                         plen += skb_frag_size(&skb_shinfo(head)->frags[i]);
 409                 clone->len = clone->data_len = head->data_len - plen;
 410                 head->data_len -= clone->len;
 411                 head->len -= clone->len;
 412                 clone->csum = 0;
 413                 clone->ip_summed = head->ip_summed;
 414
 415                 NFCT_FRAG6_CB(clone)->orig = NULL;
 416                 add_frag_mem_limit(&fq->q, clone->truesize);
 417         }
 418
 419         /* We have to remove fragment header from datagram and to relocate
 420          * header in order to calculate ICV correctly. */
 421         skb_network_header(head)[fq->nhoffset] = skb_transport_header(head)[0];
 422         memmove(head->head + sizeof(struct frag_hdr), head->head,
 423                 (head->data - head->head) - sizeof(struct frag_hdr));
 424         head->mac_header += sizeof(struct frag_hdr);
 425         head->network_header += sizeof(struct frag_hdr);
 426
 427         skb_shinfo(head)->frag_list = head->next;
 428         skb_reset_transport_header(head);
 429         skb_push(head, head->data - skb_network_header(head));
 430
 431         for (fp=head->next; fp; fp = fp->next) {
 432                 head->data_len += fp->len;
 433                 head->len += fp->len;
 434                 if (head->ip_summed != fp->ip_summed)
 435                         head->ip_summed = CHECKSUM_NONE;
 436                 else if (head->ip_summed == CHECKSUM_COMPLETE)
 437                         head->csum = csum_add(head->csum, fp->csum);
 438                 head->truesize += fp->truesize;
 439         }
 440         sub_frag_mem_limit(&fq->q, head->truesize);
 441
 442         head->local_df = 1;
 443         head->next = NULL;
 444         head->dev = dev;
 445         head->tstamp = fq->q.stamp;
 446         ipv6_hdr(head)->payload_len = htons(payload_len);
 447         ipv6_change_dsfield(ipv6_hdr(head), 0xff, ecn);
 448         IP6CB(head)->frag_max_size = sizeof(struct ipv6hdr) + fq->q.max_size;
 449
 450         /* Yes, and fold redundant checksum back. 8) */
 451         if (head->ip_summed == CHECKSUM_COMPLETE)
 452                 head->csum = csum_partial(skb_network_header(head),
 453                                           skb_network_header_len(head),
 454                                           head->csum);
 455
 456         fq->q.fragments = NULL;
 457         fq->q.fragments_tail = NULL;
 458
 459         /* all original skbs are linked into the NFCT_FRAG6_CB(head).orig */
 460         fp = skb_shinfo(head)->frag_list;
 461         if (fp && NFCT_FRAG6_CB(fp)->orig == NULL)
 462                 /* at above code, head skb is divided into two skbs. */
 463                 fp = fp->next;
 464
 465         op = NFCT_FRAG6_CB(head)->orig;
 466         for (; fp; fp = fp->next) {
 467                 struct sk_buff *orig = NFCT_FRAG6_CB(fp)->orig;
 468
 469                 op->next = orig;
 470                 op = orig;
 471                 NFCT_FRAG6_CB(fp)->orig = NULL;
 472         }
 473
 474         return head;
 475
 476 out_oversize:
 477         net_dbg_ratelimited("nf_ct_frag6_reasm: payload len = %d\n",
 478                             payload_len);
 479         goto out_fail;
 480 out_oom:
 481         net_dbg_ratelimited("nf_ct_frag6_reasm: no memory for reassembly\n");
 482 out_fail:
 483         return NULL;
 484 }
 485
 486 /*
 487  * find the header just before Fragment Header.
 488  *
 489  * if success return 0 and set ...
 490  * (*prevhdrp): the value of "Next Header Field" in the header
 491  *              just before Fragment Header.
 492  * (*prevhoff): the offset of "Next Header Field" in the header
 493  *              just before Fragment Header.
 494  * (*fhoff)   : the offset of Fragment Header.
 495  *
 496  * Based on ipv6_skip_hdr() in net/ipv6/exthdr.c
 497  *
 498  */
 499 static int
 500 find_prev_fhdr(struct sk_buff *skb, u8 *prevhdrp, int *prevhoff, int *fhoff)
 501 {
 502         u8 nexthdr = ipv6_hdr(skb)->nexthdr;
 503         const int netoff = skb_network_offset(skb);
 504         u8 prev_nhoff = netoff + offsetof(struct ipv6hdr, nexthdr);
 505         int start = netoff + sizeof(struct ipv6hdr);
 506         int len = skb->len - start;
 507         u8 prevhdr = NEXTHDR_IPV6;
 508
 509         while (nexthdr != NEXTHDR_FRAGMENT) {
 510                 struct ipv6_opt_hdr hdr;
 511                 int hdrlen;
 512
 513                 if (!ipv6_ext_hdr(nexthdr)) {
 514                         return -1;
 515                 }
 516                 if (nexthdr == NEXTHDR_NONE) {
 517                         pr_debug("next header is none\n");
 518                         return -1;
 519                 }
 520                 if (len < (int)sizeof(struct ipv6_opt_hdr)) {
 521                         pr_debug("too short\n");
 522                         return -1;
 523                 }
 524                 if (skb_copy_bits(skb, start, &hdr, sizeof(hdr)))
 525                         BUG();
 526                 if (nexthdr == NEXTHDR_AUTH)
 527                         hdrlen = (hdr.hdrlen+2)<<2;
 528                 else
 529                         hdrlen = ipv6_optlen(&hdr);
 530
 531                 prevhdr = nexthdr;
 532                 prev_nhoff = start;
 533
 534                 nexthdr = hdr.nexthdr;
 535                 len -= hdrlen;
 536                 start += hdrlen;
 537         }
 538
 539         if (len < 0)
 540                 return -1;
 541
 542         *prevhdrp = prevhdr;
 543         *prevhoff = prev_nhoff;
 544         *fhoff = start;
 545
 546         return 0;
 547 }
 548
 549 struct sk_buff *nf_ct_frag6_gather(struct sk_buff *skb, u32 user)
 550 {
 551         struct sk_buff *clone;
 552         struct net_device *dev = skb->dev;
 553         struct net *net = skb_dst(skb) ? dev_net(skb_dst(skb)->dev)
 554                                        : dev_net(skb->dev);
 555         struct frag_hdr *fhdr;
 556         struct frag_queue *fq;
 557         struct ipv6hdr *hdr;
 558         int fhoff, nhoff;
 559         u8 prevhdr;
 560         struct sk_buff *ret_skb = NULL;
 561
 562         /* Jumbo payload inhibits frag. header */
 563         if (ipv6_hdr(skb)->payload_len == 0) {
 564                 pr_debug("payload len = 0\n");
 565                 return skb;
 566         }
 567
 568         if (find_prev_fhdr(skb, &prevhdr, &nhoff, &fhoff) < 0)
 569                 return skb;
 570
 571         clone = skb_clone(skb, GFP_ATOMIC);
 572         if (clone == NULL) {
 573                 pr_debug("Can't clone skb\n");
 574                 return skb;
 575         }
 576
 577         NFCT_FRAG6_CB(clone)->orig = skb;
 578
 579         if (!pskb_may_pull(clone, fhoff + sizeof(*fhdr))) {
 580                 pr_debug("message is too short.\n");
 581                 goto ret_orig;
 582         }
 583
 584         skb_set_transport_header(clone, fhoff);
 585         hdr = ipv6_hdr(clone);
 586         fhdr = (struct frag_hdr *)skb_transport_header(clone);
 587
 588         local_bh_disable();
 589         inet_frag_evictor(&net->nf_frag.frags, &nf_frags, false);
 590         local_bh_enable();
 591
 592         fq = fq_find(net, fhdr->identification, user, &hdr->saddr, &hdr->daddr,
 593                      ip6_frag_ecn(hdr));
 594         if (fq == NULL) {
 595                 pr_debug("Can't find and can't create new queue\n");
 596                 goto ret_orig;
 597         }
 598
 599         spin_lock_bh(&fq->q.lock);
 600
 601         if (nf_ct_frag6_queue(fq, clone, fhdr, nhoff) < 0) {
 602                 spin_unlock_bh(&fq->q.lock);
 603                 pr_debug("Can't insert skb to queue\n");
 604                 inet_frag_put(&fq->q, &nf_frags);
 605                 goto ret_orig;
 606         }
 607
 608         if (fq->q.last_in == (INET_FRAG_FIRST_IN | INET_FRAG_LAST_IN) &&
 609             fq->q.meat == fq->q.len) {
 610                 ret_skb = nf_ct_frag6_reasm(fq, dev);
 611                 if (ret_skb == NULL)
 612                         pr_debug("Can't reassemble fragmented packets\n");
 613         }
 614         spin_unlock_bh(&fq->q.lock);
 615
 616         inet_frag_put(&fq->q, &nf_frags);
 617         return ret_skb;
 618
 619 ret_orig:
 620         kfree_skb(clone);
 621         return skb;
 622 }
 623
 624 void nf_ct_frag6_consume_orig(struct sk_buff *skb)
 625 {
 626         struct sk_buff *s, *s2;
 627
 628         for (s = NFCT_FRAG6_CB(skb)->orig; s;) {
 629                 s2 = s->next;
 630                 s->next = NULL;
 631                 consume_skb(s);
 632                 s = s2;
 633         }
 634 }
 635
 636 static int nf_ct_net_init(struct net *net)
 637 {
 638         net->nf_frag.frags.high_thresh = IPV6_FRAG_HIGH_THRESH;
 639         net->nf_frag.frags.low_thresh = IPV6_FRAG_LOW_THRESH;
 640         net->nf_frag.frags.timeout = IPV6_FRAG_TIMEOUT;
 641         inet_frags_init_net(&net->nf_frag.frags);
 642
 643         return nf_ct_frag6_sysctl_register(net);
 644 }
 645
 646 static void nf_ct_net_exit(struct net *net)
 647 {
 648         nf_ct_frags6_sysctl_unregister(net);
 649         inet_frags_exit_net(&net->nf_frag.frags, &nf_frags);
 650 }
 651
 652 static struct pernet_operations nf_ct_net_ops = {
 653         .init = nf_ct_net_init,
 654         .exit = nf_ct_net_exit,
 655 };
 656
 657 int nf_ct_frag6_init(void)
 658 {
 659         int ret = 0;
 660
 661         nf_frags.hashfn = nf_hashfn;
 662         nf_frags.constructor = ip6_frag_init;
 663         nf_frags.destructor = NULL;
 664         nf_frags.skb_free = nf_skb_free;
 665         nf_frags.qsize = sizeof(struct frag_queue);
 666         nf_frags.match = ip6_frag_match;
 667         nf_frags.frag_expire = nf_ct_frag6_expire;
 668         nf_frags.secret_interval = 10 * 60 * HZ;
 669         inet_frags_init(&nf_frags);
 670
 671         ret = register_pernet_subsys(&nf_ct_net_ops);
 672         if (ret)
 673                 inet_frags_fini(&nf_frags);
 674
 675         return ret;
 676 }
 677
 678 void nf_ct_frag6_cleanup(void)
 679 {
 680         unregister_pernet_subsys(&nf_ct_net_ops);
 681         inet_frags_fini(&nf_frags);
 682 }