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 static const char nf_frags_cache_name[] = "nf-frags";
  54
  55 struct nf_ct_frag6_skb_cb
  56 {
  57         struct inet6_skb_parm   h;
  58         int                     offset;
  59         struct sk_buff          *orig;
  60 };
  61
  62 #define NFCT_FRAG6_CB(skb)      ((struct nf_ct_frag6_skb_cb *)((skb)->cb))
  63
  64 static struct inet_frags nf_frags;
  65
  66 #ifdef CONFIG_SYSCTL
  67
  68 static struct ctl_table nf_ct_frag6_sysctl_table[] = {
  69         {
  70                 .procname       = "nf_conntrack_frag6_timeout",
  71                 .data           = &init_net.nf_frag.frags.timeout,
  72                 .maxlen         = sizeof(unsigned int),
  73                 .mode           = 0644,
  74                 .proc_handler   = proc_dointvec_jiffies,
  75         },
  76         {
  77                 .procname       = "nf_conntrack_frag6_low_thresh",
  78                 .data           = &init_net.nf_frag.frags.low_thresh,
  79                 .maxlen         = sizeof(unsigned long),
  80                 .mode           = 0644,
  81                 .proc_handler   = proc_doulongvec_minmax,
  82                 .extra2         = &init_net.nf_frag.frags.high_thresh
  83         },
  84         {
  85                 .procname       = "nf_conntrack_frag6_high_thresh",
  86                 .data           = &init_net.nf_frag.frags.high_thresh,
  87                 .maxlen         = sizeof(unsigned long),
  88                 .mode           = 0644,
  89                 .proc_handler   = proc_doulongvec_minmax,
  90                 .extra1         = &init_net.nf_frag.frags.low_thresh
  91         },
  92         { }
  93 };
  94
  95 static int nf_ct_frag6_sysctl_register(struct net *net)
  96 {
  97         struct ctl_table *table;
  98         struct ctl_table_header *hdr;
  99
 100         table = nf_ct_frag6_sysctl_table;
 101         if (!net_eq(net, &init_net)) {
 102                 table = kmemdup(table, sizeof(nf_ct_frag6_sysctl_table),
 103                                 GFP_KERNEL);
 104                 if (table == NULL)
 105                         goto err_alloc;
 106
 107                 table[0].data = &net->nf_frag.frags.timeout;
 108                 table[1].data = &net->nf_frag.frags.low_thresh;
 109                 table[1].extra2 = &net->nf_frag.frags.high_thresh;
 110                 table[2].data = &net->nf_frag.frags.high_thresh;
 111                 table[2].extra1 = &net->nf_frag.frags.low_thresh;
 112                 table[2].extra2 = &init_net.nf_frag.frags.high_thresh;
 113         }
 114
 115         hdr = register_net_sysctl(net, "net/netfilter", table);
 116         if (hdr == NULL)
 117                 goto err_reg;
 118
 119         net->nf_frag_frags_hdr = hdr;
 120         return 0;
 121
 122 err_reg:
 123         if (!net_eq(net, &init_net))
 124                 kfree(table);
 125 err_alloc:
 126         return -ENOMEM;
 127 }
 128
 129 static void __net_exit nf_ct_frags6_sysctl_unregister(struct net *net)
 130 {
 131         struct ctl_table *table;
 132
 133         table = net->nf_frag_frags_hdr->ctl_table_arg;
 134         unregister_net_sysctl_table(net->nf_frag_frags_hdr);
 135         if (!net_eq(net, &init_net))
 136                 kfree(table);
 137 }
 138
 139 #else
 140 static int nf_ct_frag6_sysctl_register(struct net *net)
 141 {
 142         return 0;
 143 }
 144 static void __net_exit nf_ct_frags6_sysctl_unregister(struct net *net)
 145 {
 146 }
 147 #endif
 148
 149 static inline u8 ip6_frag_ecn(const struct ipv6hdr *ipv6h)
 150 {
 151         return 1 << (ipv6_get_dsfield(ipv6h) & INET_ECN_MASK);
 152 }
 153
 154 static void nf_skb_free(struct sk_buff *skb)
 155 {
 156         if (NFCT_FRAG6_CB(skb)->orig)
 157                 kfree_skb(NFCT_FRAG6_CB(skb)->orig);
 158 }
 159
 160 static void nf_ct_frag6_expire(unsigned long data)
 161 {
 162         struct frag_queue *fq;
 163         struct net *net;
 164
 165         fq = container_of((struct inet_frag_queue *)data, struct frag_queue, q);
 166         net = container_of(fq->q.net, struct net, nf_frag.frags);
 167
 168         ip6_expire_frag_queue(net, fq);
 169 }
 170
 171 /* Creation primitives. */
 172 static struct frag_queue *fq_find(struct net *net, __be32 id, u32 user,
 173                                   const struct ipv6hdr *hdr, int iif)
 174 {
 175         struct frag_v6_compare_key key = {
 176                 .id = id,
 177                 .saddr = hdr->saddr,
 178                 .daddr = hdr->daddr,
 179                 .user = user,
 180                 .iif = iif,
 181         };
 182         struct inet_frag_queue *q;
 183
 184         q = inet_frag_find(&net->nf_frag.frags, &key);
 185         if (!q)
 186                 return NULL;
 187
 188         return container_of(q, struct frag_queue, q);
 189 }
 190
 191
 192 static int nf_ct_frag6_queue(struct frag_queue *fq, struct sk_buff *skb,
 193                              const struct frag_hdr *fhdr, int nhoff)
 194 {
 195         struct sk_buff *prev, *next;
 196         unsigned int payload_len;
 197         int offset, end;
 198         u8 ecn;
 199
 200         if (fq->q.flags & INET_FRAG_COMPLETE) {
 201                 pr_debug("Already completed\n");
 202                 goto err;
 203         }
 204
 205         payload_len = ntohs(ipv6_hdr(skb)->payload_len);
 206
 207         offset = ntohs(fhdr->frag_off) & ~0x7;
 208         end = offset + (payload_len -
 209                         ((u8 *)(fhdr + 1) - (u8 *)(ipv6_hdr(skb) + 1)));
 210
 211         if ((unsigned int)end > IPV6_MAXPLEN) {
 212                 pr_debug("offset is too large.\n");
 213                 return -1;
 214         }
 215
 216         ecn = ip6_frag_ecn(ipv6_hdr(skb));
 217
 218         if (skb->ip_summed == CHECKSUM_COMPLETE) {
 219                 const unsigned char *nh = skb_network_header(skb);
 220                 skb->csum = csum_sub(skb->csum,
 221                                      csum_partial(nh, (u8 *)(fhdr + 1) - nh,
 222                                                   0));
 223         }
 224
 225         /* Is this the final fragment? */
 226         if (!(fhdr->frag_off & htons(IP6_MF))) {
 227                 /* If we already have some bits beyond end
 228                  * or have different end, the segment is corrupted.
 229                  */
 230                 if (end < fq->q.len ||
 231                     ((fq->q.flags & INET_FRAG_LAST_IN) && end != fq->q.len)) {
 232                         pr_debug("already received last fragment\n");
 233                         goto err;
 234                 }
 235                 fq->q.flags |= INET_FRAG_LAST_IN;
 236                 fq->q.len = end;
 237         } else {
 238                 /* Check if the fragment is rounded to 8 bytes.
 239                  * Required by the RFC.
 240                  */
 241                 if (end & 0x7) {
 242                         /* RFC2460 says always send parameter problem in
 243                          * this case. -DaveM
 244                          */
 245                         pr_debug("end of fragment not rounded to 8 bytes.\n");
 246                         return -1;
 247                 }
 248                 if (end > fq->q.len) {
 249                         /* Some bits beyond end -> corruption. */
 250                         if (fq->q.flags & INET_FRAG_LAST_IN) {
 251                                 pr_debug("last packet already reached.\n");
 252                                 goto err;
 253                         }
 254                         fq->q.len = end;
 255                 }
 256         }
 257
 258         if (end == offset)
 259                 goto err;
 260
 261         /* Point into the IP datagram 'data' part. */
 262         if (!pskb_pull(skb, (u8 *) (fhdr + 1) - skb->data)) {
 263                 pr_debug("queue: message is too short.\n");
 264                 goto err;
 265         }
 266         if (pskb_trim_rcsum(skb, end - offset)) {
 267                 pr_debug("Can't trim\n");
 268                 goto err;
 269         }
 270
 271         /* Find out which fragments are in front and at the back of us
 272          * in the chain of fragments so far.  We must know where to put
 273          * this fragment, right?
 274          */
 275         prev = fq->q.fragments_tail;
 276         if (!prev || NFCT_FRAG6_CB(prev)->offset < offset) {
 277                 next = NULL;
 278                 goto found;
 279         }
 280         prev = NULL;
 281         for (next = fq->q.fragments; next != NULL; next = next->next) {
 282                 if (NFCT_FRAG6_CB(next)->offset >= offset)
 283                         break;  /* bingo! */
 284                 prev = next;
 285         }
 286
 287 found:
 288         /* RFC5722, Section 4:
 289          *                                  When reassembling an IPv6 datagram, if
 290          *   one or more its constituent fragments is determined to be an
 291          *   overlapping fragment, the entire datagram (and any constituent
 292          *   fragments, including those not yet received) MUST be silently
 293          *   discarded.
 294          */
 295
 296         /* Check for overlap with preceding fragment. */
 297         if (prev &&
 298             (NFCT_FRAG6_CB(prev)->offset + prev->len) > offset)
 299                 goto discard_fq;
 300
 301         /* Look for overlap with succeeding segment. */
 302         if (next && NFCT_FRAG6_CB(next)->offset < end)
 303                 goto discard_fq;
 304
 305         NFCT_FRAG6_CB(skb)->offset = offset;
 306
 307         /* Insert this fragment in the chain of fragments. */
 308         skb->next = next;
 309         if (!next)
 310                 fq->q.fragments_tail = skb;
 311         if (prev)
 312                 prev->next = skb;
 313         else
 314                 fq->q.fragments = skb;
 315
 316         if (skb->dev) {
 317                 fq->iif = skb->dev->ifindex;
 318                 skb->dev = NULL;
 319         }
 320         fq->q.stamp = skb->tstamp;
 321         fq->q.meat += skb->len;
 322         fq->ecn |= ecn;
 323         if (payload_len > fq->q.max_size)
 324                 fq->q.max_size = payload_len;
 325         add_frag_mem_limit(fq->q.net, skb->truesize);
 326
 327         /* The first fragment.
 328          * nhoffset is obtained from the first fragment, of course.
 329          */
 330         if (offset == 0) {
 331                 fq->nhoffset = nhoff;
 332                 fq->q.flags |= INET_FRAG_FIRST_IN;
 333         }
 334
 335         return 0;
 336
 337 discard_fq:
 338         inet_frag_kill(&fq->q);
 339 err:
 340         return -1;
 341 }
 342
 343 /*
 344  *      Check if this packet is complete.
 345  *      Returns NULL on failure by any reason, and pointer
 346  *      to current nexthdr field in reassembled frame.
 347  *
 348  *      It is called with locked fq, and caller must check that
 349  *      queue is eligible for reassembly i.e. it is not COMPLETE,
 350  *      the last and the first frames arrived and all the bits are here.
 351  */
 352 static struct sk_buff *
 353 nf_ct_frag6_reasm(struct frag_queue *fq, struct net_device *dev)
 354 {
 355         struct sk_buff *fp, *op, *head = fq->q.fragments;
 356         int    payload_len;
 357         u8 ecn;
 358
 359         inet_frag_kill(&fq->q);
 360
 361         WARN_ON(head == NULL);
 362         WARN_ON(NFCT_FRAG6_CB(head)->offset != 0);
 363
 364         ecn = ip_frag_ecn_table[fq->ecn];
 365         if (unlikely(ecn == 0xff))
 366                 goto out_fail;
 367
 368         /* Unfragmented part is taken from the first segment. */
 369         payload_len = ((head->data - skb_network_header(head)) -
 370                        sizeof(struct ipv6hdr) + fq->q.len -
 371                        sizeof(struct frag_hdr));
 372         if (payload_len > IPV6_MAXPLEN) {
 373                 pr_debug("payload len is too large.\n");
 374                 goto out_oversize;
 375         }
 376
 377         /* Head of list must not be cloned. */
 378         if (skb_unclone(head, GFP_ATOMIC)) {
 379                 pr_debug("skb is cloned but can't expand head");
 380                 goto out_oom;
 381         }
 382
 383         /* If the first fragment is fragmented itself, we split
 384          * it to two chunks: the first with data and paged part
 385          * and the second, holding only fragments. */
 386         if (skb_has_frag_list(head)) {
 387                 struct sk_buff *clone;
 388                 int i, plen = 0;
 389
 390                 clone = alloc_skb(0, GFP_ATOMIC);
 391                 if (clone == NULL)
 392                         goto out_oom;
 393
 394                 clone->next = head->next;
 395                 head->next = clone;
 396                 skb_shinfo(clone)->frag_list = skb_shinfo(head)->frag_list;
 397                 skb_frag_list_init(head);
 398                 for (i = 0; i < skb_shinfo(head)->nr_frags; i++)
 399                         plen += skb_frag_size(&skb_shinfo(head)->frags[i]);
 400                 clone->len = clone->data_len = head->data_len - plen;
 401                 head->data_len -= clone->len;
 402                 head->len -= clone->len;
 403                 clone->csum = 0;
 404                 clone->ip_summed = head->ip_summed;
 405
 406                 NFCT_FRAG6_CB(clone)->orig = NULL;
 407                 add_frag_mem_limit(fq->q.net, clone->truesize);
 408         }
 409
 410         /* We have to remove fragment header from datagram and to relocate
 411          * header in order to calculate ICV correctly. */
 412         skb_network_header(head)[fq->nhoffset] = skb_transport_header(head)[0];
 413         memmove(head->head + sizeof(struct frag_hdr), head->head,
 414                 (head->data - head->head) - sizeof(struct frag_hdr));
 415         head->mac_header += sizeof(struct frag_hdr);
 416         head->network_header += sizeof(struct frag_hdr);
 417
 418         skb_shinfo(head)->frag_list = head->next;
 419         skb_reset_transport_header(head);
 420         skb_push(head, head->data - skb_network_header(head));
 421
 422         for (fp = head->next; fp; fp = fp->next) {
 423                 head->data_len += fp->len;
 424                 head->len += fp->len;
 425                 if (head->ip_summed != fp->ip_summed)
 426                         head->ip_summed = CHECKSUM_NONE;
 427                 else if (head->ip_summed == CHECKSUM_COMPLETE)
 428                         head->csum = csum_add(head->csum, fp->csum);
 429                 head->truesize += fp->truesize;
 430                 fp->sk = NULL;
 431         }
 432         sub_frag_mem_limit(fq->q.net, head->truesize);
 433
 434         head->ignore_df = 1;
 435         head->next = NULL;
 436         head->dev = dev;
 437         head->tstamp = fq->q.stamp;
 438         ipv6_hdr(head)->payload_len = htons(payload_len);
 439         ipv6_change_dsfield(ipv6_hdr(head), 0xff, ecn);
 440         IP6CB(head)->frag_max_size = sizeof(struct ipv6hdr) + fq->q.max_size;
 441
 442         /* Yes, and fold redundant checksum back. 8) */
 443         if (head->ip_summed == CHECKSUM_COMPLETE)
 444                 head->csum = csum_partial(skb_network_header(head),
 445                                           skb_network_header_len(head),
 446                                           head->csum);
 447
 448         fq->q.fragments = NULL;
 449         fq->q.rb_fragments = RB_ROOT;
 450         fq->q.fragments_tail = NULL;
 451
 452         /* all original skbs are linked into the NFCT_FRAG6_CB(head).orig */
 453         fp = skb_shinfo(head)->frag_list;
 454         if (fp && NFCT_FRAG6_CB(fp)->orig == NULL)
 455                 /* at above code, head skb is divided into two skbs. */
 456                 fp = fp->next;
 457
 458         op = NFCT_FRAG6_CB(head)->orig;
 459         for (; fp; fp = fp->next) {
 460                 struct sk_buff *orig = NFCT_FRAG6_CB(fp)->orig;
 461
 462                 op->next = orig;
 463                 op = orig;
 464                 NFCT_FRAG6_CB(fp)->orig = NULL;
 465         }
 466
 467         return head;
 468
 469 out_oversize:
 470         net_dbg_ratelimited("nf_ct_frag6_reasm: payload len = %d\n",
 471                             payload_len);
 472         goto out_fail;
 473 out_oom:
 474         net_dbg_ratelimited("nf_ct_frag6_reasm: no memory for reassembly\n");
 475 out_fail:
 476         return NULL;
 477 }
 478
 479 /*
 480  * find the header just before Fragment Header.
 481  *
 482  * if success return 0 and set ...
 483  * (*prevhdrp): the value of "Next Header Field" in the header
 484  *              just before Fragment Header.
 485  * (*prevhoff): the offset of "Next Header Field" in the header
 486  *              just before Fragment Header.
 487  * (*fhoff)   : the offset of Fragment Header.
 488  *
 489  * Based on ipv6_skip_hdr() in net/ipv6/exthdr.c
 490  *
 491  */
 492 static int
 493 find_prev_fhdr(struct sk_buff *skb, u8 *prevhdrp, int *prevhoff, int *fhoff)
 494 {
 495         u8 nexthdr = ipv6_hdr(skb)->nexthdr;
 496         const int netoff = skb_network_offset(skb);
 497         u8 prev_nhoff = netoff + offsetof(struct ipv6hdr, nexthdr);
 498         int start = netoff + sizeof(struct ipv6hdr);
 499         int len = skb->len - start;
 500         u8 prevhdr = NEXTHDR_IPV6;
 501
 502         while (nexthdr != NEXTHDR_FRAGMENT) {
 503                 struct ipv6_opt_hdr hdr;
 504                 int hdrlen;
 505
 506                 if (!ipv6_ext_hdr(nexthdr)) {
 507                         return -1;
 508                 }
 509                 if (nexthdr == NEXTHDR_NONE) {
 510                         pr_debug("next header is none\n");
 511                         return -1;
 512                 }
 513                 if (len < (int)sizeof(struct ipv6_opt_hdr)) {
 514                         pr_debug("too short\n");
 515                         return -1;
 516                 }
 517                 if (skb_copy_bits(skb, start, &hdr, sizeof(hdr)))
 518                         BUG();
 519                 if (nexthdr == NEXTHDR_AUTH)
 520                         hdrlen = (hdr.hdrlen+2)<<2;
 521                 else
 522                         hdrlen = ipv6_optlen(&hdr);
 523
 524                 prevhdr = nexthdr;
 525                 prev_nhoff = start;
 526
 527                 nexthdr = hdr.nexthdr;
 528                 len -= hdrlen;
 529                 start += hdrlen;
 530         }
 531
 532         if (len < 0)
 533                 return -1;
 534
 535         *prevhdrp = prevhdr;
 536         *prevhoff = prev_nhoff;
 537         *fhoff = start;
 538
 539         return 0;
 540 }
 541
 542 struct sk_buff *nf_ct_frag6_gather(struct net *net, struct sk_buff *skb, u32 user)
 543 {
 544         struct sk_buff *clone;
 545         struct net_device *dev = skb->dev;
 546         struct frag_hdr *fhdr;
 547         struct frag_queue *fq;
 548         struct ipv6hdr *hdr;
 549         int fhoff, nhoff;
 550         u8 prevhdr;
 551         struct sk_buff *ret_skb = NULL;
 552
 553         /* Jumbo payload inhibits frag. header */
 554         if (ipv6_hdr(skb)->payload_len == 0) {
 555                 pr_debug("payload len = 0\n");
 556                 return skb;
 557         }
 558
 559         if (find_prev_fhdr(skb, &prevhdr, &nhoff, &fhoff) < 0)
 560                 return skb;
 561
 562         clone = skb_clone(skb, GFP_ATOMIC);
 563         if (clone == NULL) {
 564                 pr_debug("Can't clone skb\n");
 565                 return skb;
 566         }
 567
 568         NFCT_FRAG6_CB(clone)->orig = skb;
 569
 570         if (!pskb_may_pull(clone, fhoff + sizeof(*fhdr))) {
 571                 pr_debug("message is too short.\n");
 572                 goto ret_orig;
 573         }
 574
 575         skb_set_transport_header(clone, fhoff);
 576         hdr = ipv6_hdr(clone);
 577         fhdr = (struct frag_hdr *)skb_transport_header(clone);
 578
 579         if (clone->len - skb_network_offset(clone) < IPV6_MIN_MTU &&
 580             fhdr->frag_off & htons(IP6_MF))
 581                 goto ret_orig;
 582
 583         skb_orphan(skb);
 584         fq = fq_find(net, fhdr->identification, user, hdr,
 585                      skb->dev ? skb->dev->ifindex : 0);
 586         if (fq == NULL) {
 587                 pr_debug("Can't find and can't create new queue\n");
 588                 goto ret_orig;
 589         }
 590
 591         spin_lock_bh(&fq->q.lock);
 592
 593         if (nf_ct_frag6_queue(fq, clone, fhdr, nhoff) < 0) {
 594                 spin_unlock_bh(&fq->q.lock);
 595                 pr_debug("Can't insert skb to queue\n");
 596                 inet_frag_put(&fq->q);
 597                 goto ret_orig;
 598         }
 599
 600         if (fq->q.flags == (INET_FRAG_FIRST_IN | INET_FRAG_LAST_IN) &&
 601             fq->q.meat == fq->q.len) {
 602                 ret_skb = nf_ct_frag6_reasm(fq, dev);
 603                 if (ret_skb == NULL)
 604                         pr_debug("Can't reassemble fragmented packets\n");
 605         }
 606         spin_unlock_bh(&fq->q.lock);
 607
 608         inet_frag_put(&fq->q);
 609         return ret_skb;
 610
 611 ret_orig:
 612         kfree_skb(clone);
 613         return skb;
 614 }
 615 EXPORT_SYMBOL_GPL(nf_ct_frag6_gather);
 616
 617 void nf_ct_frag6_consume_orig(struct sk_buff *skb)
 618 {
 619         struct sk_buff *s, *s2;
 620
 621         for (s = NFCT_FRAG6_CB(skb)->orig; s;) {
 622                 s2 = s->next;
 623                 s->next = NULL;
 624                 consume_skb(s);
 625                 s = s2;
 626         }
 627 }
 628 EXPORT_SYMBOL_GPL(nf_ct_frag6_consume_orig);
 629
 630 static int nf_ct_net_init(struct net *net)
 631 {
 632         int res;
 633
 634         net->nf_frag.frags.high_thresh = IPV6_FRAG_HIGH_THRESH;
 635         net->nf_frag.frags.low_thresh = IPV6_FRAG_LOW_THRESH;
 636         net->nf_frag.frags.timeout = IPV6_FRAG_TIMEOUT;
 637         net->nf_frag.frags.f = &nf_frags;
 638
 639         res = inet_frags_init_net(&net->nf_frag.frags);
 640         if (res < 0)
 641                 return res;
 642         res = nf_ct_frag6_sysctl_register(net);
 643         if (res < 0)
 644                 inet_frags_exit_net(&net->nf_frag.frags);
 645         return res;
 646 }
 647
 648 static void nf_ct_net_exit(struct net *net)
 649 {
 650         nf_ct_frags6_sysctl_unregister(net);
 651         inet_frags_exit_net(&net->nf_frag.frags);
 652 }
 653
 654 static struct pernet_operations nf_ct_net_ops = {
 655         .init = nf_ct_net_init,
 656         .exit = nf_ct_net_exit,
 657 };
 658
 659 int nf_ct_frag6_init(void)
 660 {
 661         int ret = 0;
 662
 663         nf_frags.constructor = ip6_frag_init;
 664         nf_frags.destructor = NULL;
 665         nf_frags.skb_free = nf_skb_free;
 666         nf_frags.qsize = sizeof(struct frag_queue);
 667         nf_frags.frag_expire = nf_ct_frag6_expire;
 668         nf_frags.frags_cache_name = nf_frags_cache_name;
 669         nf_frags.rhash_params = ip6_rhash_params;
 670         ret = inet_frags_init(&nf_frags);
 671         if (ret)
 672                 goto out;
 673         ret = register_pernet_subsys(&nf_ct_net_ops);
 674         if (ret)
 675                 inet_frags_fini(&nf_frags);
 676
 677 out:
 678         return ret;
 679 }
 680
 681 void nf_ct_frag6_cleanup(void)
 682 {
 683         unregister_pernet_subsys(&nf_ct_net_ops);
 684         inet_frags_fini(&nf_frags);
 685 }