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 static int zero;
  68
  69 static struct ctl_table nf_ct_frag6_sysctl_table[] = {
  70         {
  71                 .procname       = "nf_conntrack_frag6_timeout",
  72                 .data           = &init_net.nf_frag.frags.timeout,
  73                 .maxlen         = sizeof(unsigned int),
  74                 .mode           = 0644,
  75                 .proc_handler   = proc_dointvec_jiffies,
  76         },
  77         {
  78                 .procname       = "nf_conntrack_frag6_low_thresh",
  79                 .data           = &init_net.nf_frag.frags.low_thresh,
  80                 .maxlen         = sizeof(unsigned int),
  81                 .mode           = 0644,
  82                 .proc_handler   = proc_dointvec_minmax,
  83                 .extra1         = &zero,
  84                 .extra2         = &init_net.nf_frag.frags.high_thresh
  85         },
  86         {
  87                 .procname       = "nf_conntrack_frag6_high_thresh",
  88                 .data           = &init_net.nf_frag.frags.high_thresh,
  89                 .maxlen         = sizeof(unsigned int),
  90                 .mode           = 0644,
  91                 .proc_handler   = proc_dointvec_minmax,
  92                 .extra1         = &init_net.nf_frag.frags.low_thresh
  93         },
  94         { }
  95 };
  96
  97 static int nf_ct_frag6_sysctl_register(struct net *net)
  98 {
  99         struct ctl_table *table;
 100         struct ctl_table_header *hdr;
 101
 102         table = nf_ct_frag6_sysctl_table;
 103         if (!net_eq(net, &init_net)) {
 104                 table = kmemdup(table, sizeof(nf_ct_frag6_sysctl_table),
 105                                 GFP_KERNEL);
 106                 if (table == NULL)
 107                         goto err_alloc;
 108
 109                 table[0].data = &net->nf_frag.frags.timeout;
 110                 table[1].data = &net->nf_frag.frags.low_thresh;
 111                 table[1].extra2 = &net->nf_frag.frags.high_thresh;
 112                 table[2].data = &net->nf_frag.frags.high_thresh;
 113                 table[2].extra1 = &net->nf_frag.frags.low_thresh;
 114                 table[2].extra2 = &init_net.nf_frag.frags.high_thresh;
 115         }
 116
 117         hdr = register_net_sysctl(net, "net/netfilter", table);
 118         if (hdr == NULL)
 119                 goto err_reg;
 120
 121         net->nf_frag.sysctl.frags_hdr = hdr;
 122         return 0;
 123
 124 err_reg:
 125         if (!net_eq(net, &init_net))
 126                 kfree(table);
 127 err_alloc:
 128         return -ENOMEM;
 129 }
 130
 131 static void __net_exit nf_ct_frags6_sysctl_unregister(struct net *net)
 132 {
 133         struct ctl_table *table;
 134
 135         table = net->nf_frag.sysctl.frags_hdr->ctl_table_arg;
 136         unregister_net_sysctl_table(net->nf_frag.sysctl.frags_hdr);
 137         if (!net_eq(net, &init_net))
 138                 kfree(table);
 139 }
 140
 141 #else
 142 static int nf_ct_frag6_sysctl_register(struct net *net)
 143 {
 144         return 0;
 145 }
 146 static void __net_exit nf_ct_frags6_sysctl_unregister(struct net *net)
 147 {
 148 }
 149 #endif
 150
 151 static inline u8 ip6_frag_ecn(const struct ipv6hdr *ipv6h)
 152 {
 153         return 1 << (ipv6_get_dsfield(ipv6h) & INET_ECN_MASK);
 154 }
 155
 156 static unsigned int nf_hash_frag(__be32 id, const struct in6_addr *saddr,
 157                                  const struct in6_addr *daddr)
 158 {
 159         net_get_random_once(&nf_frags.rnd, sizeof(nf_frags.rnd));
 160         return jhash_3words(ipv6_addr_hash(saddr), ipv6_addr_hash(daddr),
 161                             (__force u32)id, nf_frags.rnd);
 162 }
 163
 164
 165 static unsigned int nf_hashfn(const struct inet_frag_queue *q)
 166 {
 167         const struct frag_queue *nq;
 168
 169         nq = container_of(q, struct frag_queue, q);
 170         return nf_hash_frag(nq->id, &nq->saddr, &nq->daddr);
 171 }
 172
 173 static void nf_skb_free(struct sk_buff *skb)
 174 {
 175         if (NFCT_FRAG6_CB(skb)->orig)
 176                 kfree_skb(NFCT_FRAG6_CB(skb)->orig);
 177 }
 178
 179 static void nf_ct_frag6_expire(unsigned long data)
 180 {
 181         struct frag_queue *fq;
 182         struct net *net;
 183
 184         fq = container_of((struct inet_frag_queue *)data, struct frag_queue, q);
 185         net = container_of(fq->q.net, struct net, nf_frag.frags);
 186
 187         ip6_expire_frag_queue(net, fq, &nf_frags);
 188 }
 189
 190 /* Creation primitives. */
 191 static inline struct frag_queue *fq_find(struct net *net, __be32 id,
 192                                          u32 user, struct in6_addr *src,
 193                                          struct in6_addr *dst, u8 ecn)
 194 {
 195         struct inet_frag_queue *q;
 196         struct ip6_create_arg arg;
 197         unsigned int hash;
 198
 199         arg.id = id;
 200         arg.user = user;
 201         arg.src = src;
 202         arg.dst = dst;
 203         arg.ecn = ecn;
 204
 205         local_bh_disable();
 206         hash = nf_hash_frag(id, src, dst);
 207
 208         q = inet_frag_find(&net->nf_frag.frags, &nf_frags, &arg, hash);
 209         local_bh_enable();
 210         if (IS_ERR_OR_NULL(q)) {
 211                 inet_frag_maybe_warn_overflow(q, pr_fmt());
 212                 return NULL;
 213         }
 214         return container_of(q, struct frag_queue, q);
 215 }
 216
 217
 218 static int nf_ct_frag6_queue(struct frag_queue *fq, struct sk_buff *skb,
 219                              const struct frag_hdr *fhdr, int nhoff)
 220 {
 221         struct sk_buff *prev, *next;
 222         unsigned int payload_len;
 223         int offset, end;
 224         u8 ecn;
 225
 226         if (fq->q.flags & INET_FRAG_COMPLETE) {
 227                 pr_debug("Already completed\n");
 228                 goto err;
 229         }
 230
 231         payload_len = ntohs(ipv6_hdr(skb)->payload_len);
 232
 233         offset = ntohs(fhdr->frag_off) & ~0x7;
 234         end = offset + (payload_len -
 235                         ((u8 *)(fhdr + 1) - (u8 *)(ipv6_hdr(skb) + 1)));
 236
 237         if ((unsigned int)end > IPV6_MAXPLEN) {
 238                 pr_debug("offset is too large.\n");
 239                 return -1;
 240         }
 241
 242         ecn = ip6_frag_ecn(ipv6_hdr(skb));
 243
 244         if (skb->ip_summed == CHECKSUM_COMPLETE) {
 245                 const unsigned char *nh = skb_network_header(skb);
 246                 skb->csum = csum_sub(skb->csum,
 247                                      csum_partial(nh, (u8 *)(fhdr + 1) - nh,
 248                                                   0));
 249         }
 250
 251         /* Is this the final fragment? */
 252         if (!(fhdr->frag_off & htons(IP6_MF))) {
 253                 /* If we already have some bits beyond end
 254                  * or have different end, the segment is corrupted.
 255                  */
 256                 if (end < fq->q.len ||
 257                     ((fq->q.flags & INET_FRAG_LAST_IN) && end != fq->q.len)) {
 258                         pr_debug("already received last fragment\n");
 259                         goto err;
 260                 }
 261                 fq->q.flags |= INET_FRAG_LAST_IN;
 262                 fq->q.len = end;
 263         } else {
 264                 /* Check if the fragment is rounded to 8 bytes.
 265                  * Required by the RFC.
 266                  */
 267                 if (end & 0x7) {
 268                         /* RFC2460 says always send parameter problem in
 269                          * this case. -DaveM
 270                          */
 271                         pr_debug("end of fragment not rounded to 8 bytes.\n");
 272                         return -1;
 273                 }
 274                 if (end > fq->q.len) {
 275                         /* Some bits beyond end -> corruption. */
 276                         if (fq->q.flags & INET_FRAG_LAST_IN) {
 277                                 pr_debug("last packet already reached.\n");
 278                                 goto err;
 279                         }
 280                         fq->q.len = end;
 281                 }
 282         }
 283
 284         if (end == offset)
 285                 goto err;
 286
 287         /* Point into the IP datagram 'data' part. */
 288         if (!pskb_pull(skb, (u8 *) (fhdr + 1) - skb->data)) {
 289                 pr_debug("queue: message is too short.\n");
 290                 goto err;
 291         }
 292         if (pskb_trim_rcsum(skb, end - offset)) {
 293                 pr_debug("Can't trim\n");
 294                 goto err;
 295         }
 296
 297         /* Find out which fragments are in front and at the back of us
 298          * in the chain of fragments so far.  We must know where to put
 299          * this fragment, right?
 300          */
 301         prev = fq->q.fragments_tail;
 302         if (!prev || NFCT_FRAG6_CB(prev)->offset < offset) {
 303                 next = NULL;
 304                 goto found;
 305         }
 306         prev = NULL;
 307         for (next = fq->q.fragments; next != NULL; next = next->next) {
 308                 if (NFCT_FRAG6_CB(next)->offset >= offset)
 309                         break;  /* bingo! */
 310                 prev = next;
 311         }
 312
 313 found:
 314         /* RFC5722, Section 4:
 315          *                                  When reassembling an IPv6 datagram, if
 316          *   one or more its constituent fragments is determined to be an
 317          *   overlapping fragment, the entire datagram (and any constituent
 318          *   fragments, including those not yet received) MUST be silently
 319          *   discarded.
 320          */
 321
 322         /* Check for overlap with preceding fragment. */
 323         if (prev &&
 324             (NFCT_FRAG6_CB(prev)->offset + prev->len) > offset)
 325                 goto discard_fq;
 326
 327         /* Look for overlap with succeeding segment. */
 328         if (next && NFCT_FRAG6_CB(next)->offset < end)
 329                 goto discard_fq;
 330
 331         NFCT_FRAG6_CB(skb)->offset = offset;
 332
 333         /* Insert this fragment in the chain of fragments. */
 334         skb->next = next;
 335         if (!next)
 336                 fq->q.fragments_tail = skb;
 337         if (prev)
 338                 prev->next = skb;
 339         else
 340                 fq->q.fragments = skb;
 341
 342         if (skb->dev) {
 343                 fq->iif = skb->dev->ifindex;
 344                 skb->dev = NULL;
 345         }
 346         fq->q.stamp = skb->tstamp;
 347         fq->q.meat += skb->len;
 348         fq->ecn |= ecn;
 349         if (payload_len > fq->q.max_size)
 350                 fq->q.max_size = payload_len;
 351         add_frag_mem_limit(fq->q.net, skb->truesize);
 352
 353         /* The first fragment.
 354          * nhoffset is obtained from the first fragment, of course.
 355          */
 356         if (offset == 0) {
 357                 fq->nhoffset = nhoff;
 358                 fq->q.flags |= INET_FRAG_FIRST_IN;
 359         }
 360
 361         return 0;
 362
 363 discard_fq:
 364         inet_frag_kill(&fq->q, &nf_frags);
 365 err:
 366         return -1;
 367 }
 368
 369 /*
 370  *      Check if this packet is complete.
 371  *      Returns NULL on failure by any reason, and pointer
 372  *      to current nexthdr field in reassembled frame.
 373  *
 374  *      It is called with locked fq, and caller must check that
 375  *      queue is eligible for reassembly i.e. it is not COMPLETE,
 376  *      the last and the first frames arrived and all the bits are here.
 377  */
 378 static struct sk_buff *
 379 nf_ct_frag6_reasm(struct frag_queue *fq, struct net_device *dev)
 380 {
 381         struct sk_buff *fp, *op, *head = fq->q.fragments;
 382         int    payload_len;
 383         u8 ecn;
 384
 385         inet_frag_kill(&fq->q, &nf_frags);
 386
 387         WARN_ON(head == NULL);
 388         WARN_ON(NFCT_FRAG6_CB(head)->offset != 0);
 389
 390         ecn = ip_frag_ecn_table[fq->ecn];
 391         if (unlikely(ecn == 0xff))
 392                 goto out_fail;
 393
 394         /* Unfragmented part is taken from the first segment. */
 395         payload_len = ((head->data - skb_network_header(head)) -
 396                        sizeof(struct ipv6hdr) + fq->q.len -
 397                        sizeof(struct frag_hdr));
 398         if (payload_len > IPV6_MAXPLEN) {
 399                 pr_debug("payload len is too large.\n");
 400                 goto out_oversize;
 401         }
 402
 403         /* Head of list must not be cloned. */
 404         if (skb_unclone(head, GFP_ATOMIC)) {
 405                 pr_debug("skb is cloned but can't expand head");
 406                 goto out_oom;
 407         }
 408
 409         /* If the first fragment is fragmented itself, we split
 410          * it to two chunks: the first with data and paged part
 411          * and the second, holding only fragments. */
 412         if (skb_has_frag_list(head)) {
 413                 struct sk_buff *clone;
 414                 int i, plen = 0;
 415
 416                 clone = alloc_skb(0, GFP_ATOMIC);
 417                 if (clone == NULL)
 418                         goto out_oom;
 419
 420                 clone->next = head->next;
 421                 head->next = clone;
 422                 skb_shinfo(clone)->frag_list = skb_shinfo(head)->frag_list;
 423                 skb_frag_list_init(head);
 424                 for (i = 0; i < skb_shinfo(head)->nr_frags; i++)
 425                         plen += skb_frag_size(&skb_shinfo(head)->frags[i]);
 426                 clone->len = clone->data_len = head->data_len - plen;
 427                 head->data_len -= clone->len;
 428                 head->len -= clone->len;
 429                 clone->csum = 0;
 430                 clone->ip_summed = head->ip_summed;
 431
 432                 NFCT_FRAG6_CB(clone)->orig = NULL;
 433                 add_frag_mem_limit(fq->q.net, clone->truesize);
 434         }
 435
 436         /* We have to remove fragment header from datagram and to relocate
 437          * header in order to calculate ICV correctly. */
 438         skb_network_header(head)[fq->nhoffset] = skb_transport_header(head)[0];
 439         memmove(head->head + sizeof(struct frag_hdr), head->head,
 440                 (head->data - head->head) - sizeof(struct frag_hdr));
 441         head->mac_header += sizeof(struct frag_hdr);
 442         head->network_header += sizeof(struct frag_hdr);
 443
 444         skb_shinfo(head)->frag_list = head->next;
 445         skb_reset_transport_header(head);
 446         skb_push(head, head->data - skb_network_header(head));
 447
 448         for (fp=head->next; fp; fp = fp->next) {
 449                 head->data_len += fp->len;
 450                 head->len += fp->len;
 451                 if (head->ip_summed != fp->ip_summed)
 452                         head->ip_summed = CHECKSUM_NONE;
 453                 else if (head->ip_summed == CHECKSUM_COMPLETE)
 454                         head->csum = csum_add(head->csum, fp->csum);
 455                 head->truesize += fp->truesize;
 456         }
 457         sub_frag_mem_limit(fq->q.net, head->truesize);
 458
 459         head->ignore_df = 1;
 460         head->next = NULL;
 461         head->dev = dev;
 462         head->tstamp = fq->q.stamp;
 463         ipv6_hdr(head)->payload_len = htons(payload_len);
 464         ipv6_change_dsfield(ipv6_hdr(head), 0xff, ecn);
 465         IP6CB(head)->frag_max_size = sizeof(struct ipv6hdr) + fq->q.max_size;
 466
 467         /* Yes, and fold redundant checksum back. 8) */
 468         if (head->ip_summed == CHECKSUM_COMPLETE)
 469                 head->csum = csum_partial(skb_network_header(head),
 470                                           skb_network_header_len(head),
 471                                           head->csum);
 472
 473         fq->q.fragments = NULL;
 474         fq->q.fragments_tail = NULL;
 475
 476         /* all original skbs are linked into the NFCT_FRAG6_CB(head).orig */
 477         fp = skb_shinfo(head)->frag_list;
 478         if (fp && NFCT_FRAG6_CB(fp)->orig == NULL)
 479                 /* at above code, head skb is divided into two skbs. */
 480                 fp = fp->next;
 481
 482         op = NFCT_FRAG6_CB(head)->orig;
 483         for (; fp; fp = fp->next) {
 484                 struct sk_buff *orig = NFCT_FRAG6_CB(fp)->orig;
 485
 486                 op->next = orig;
 487                 op = orig;
 488                 NFCT_FRAG6_CB(fp)->orig = NULL;
 489         }
 490
 491         return head;
 492
 493 out_oversize:
 494         net_dbg_ratelimited("nf_ct_frag6_reasm: payload len = %d\n",
 495                             payload_len);
 496         goto out_fail;
 497 out_oom:
 498         net_dbg_ratelimited("nf_ct_frag6_reasm: no memory for reassembly\n");
 499 out_fail:
 500         return NULL;
 501 }
 502
 503 /*
 504  * find the header just before Fragment Header.
 505  *
 506  * if success return 0 and set ...
 507  * (*prevhdrp): the value of "Next Header Field" in the header
 508  *              just before Fragment Header.
 509  * (*prevhoff): the offset of "Next Header Field" in the header
 510  *              just before Fragment Header.
 511  * (*fhoff)   : the offset of Fragment Header.
 512  *
 513  * Based on ipv6_skip_hdr() in net/ipv6/exthdr.c
 514  *
 515  */
 516 static int
 517 find_prev_fhdr(struct sk_buff *skb, u8 *prevhdrp, int *prevhoff, int *fhoff)
 518 {
 519         u8 nexthdr = ipv6_hdr(skb)->nexthdr;
 520         const int netoff = skb_network_offset(skb);
 521         u8 prev_nhoff = netoff + offsetof(struct ipv6hdr, nexthdr);
 522         int start = netoff + sizeof(struct ipv6hdr);
 523         int len = skb->len - start;
 524         u8 prevhdr = NEXTHDR_IPV6;
 525
 526         while (nexthdr != NEXTHDR_FRAGMENT) {
 527                 struct ipv6_opt_hdr hdr;
 528                 int hdrlen;
 529
 530                 if (!ipv6_ext_hdr(nexthdr)) {
 531                         return -1;
 532                 }
 533                 if (nexthdr == NEXTHDR_NONE) {
 534                         pr_debug("next header is none\n");
 535                         return -1;
 536                 }
 537                 if (len < (int)sizeof(struct ipv6_opt_hdr)) {
 538                         pr_debug("too short\n");
 539                         return -1;
 540                 }
 541                 if (skb_copy_bits(skb, start, &hdr, sizeof(hdr)))
 542                         BUG();
 543                 if (nexthdr == NEXTHDR_AUTH)
 544                         hdrlen = (hdr.hdrlen+2)<<2;
 545                 else
 546                         hdrlen = ipv6_optlen(&hdr);
 547
 548                 prevhdr = nexthdr;
 549                 prev_nhoff = start;
 550
 551                 nexthdr = hdr.nexthdr;
 552                 len -= hdrlen;
 553                 start += hdrlen;
 554         }
 555
 556         if (len < 0)
 557                 return -1;
 558
 559         *prevhdrp = prevhdr;
 560         *prevhoff = prev_nhoff;
 561         *fhoff = start;
 562
 563         return 0;
 564 }
 565
 566 struct sk_buff *nf_ct_frag6_gather(struct sk_buff *skb, u32 user)
 567 {
 568         struct sk_buff *clone;
 569         struct net_device *dev = skb->dev;
 570         struct net *net = skb_dst(skb) ? dev_net(skb_dst(skb)->dev)
 571                                        : dev_net(skb->dev);
 572         struct frag_hdr *fhdr;
 573         struct frag_queue *fq;
 574         struct ipv6hdr *hdr;
 575         int fhoff, nhoff;
 576         u8 prevhdr;
 577         struct sk_buff *ret_skb = NULL;
 578
 579         /* Jumbo payload inhibits frag. header */
 580         if (ipv6_hdr(skb)->payload_len == 0) {
 581                 pr_debug("payload len = 0\n");
 582                 return skb;
 583         }
 584
 585         if (find_prev_fhdr(skb, &prevhdr, &nhoff, &fhoff) < 0)
 586                 return skb;
 587
 588         clone = skb_clone(skb, GFP_ATOMIC);
 589         if (clone == NULL) {
 590                 pr_debug("Can't clone skb\n");
 591                 return skb;
 592         }
 593
 594         NFCT_FRAG6_CB(clone)->orig = skb;
 595
 596         if (!pskb_may_pull(clone, fhoff + sizeof(*fhdr))) {
 597                 pr_debug("message is too short.\n");
 598                 goto ret_orig;
 599         }
 600
 601         skb_set_transport_header(clone, fhoff);
 602         hdr = ipv6_hdr(clone);
 603         fhdr = (struct frag_hdr *)skb_transport_header(clone);
 604
 605         fq = fq_find(net, fhdr->identification, user, &hdr->saddr, &hdr->daddr,
 606                      ip6_frag_ecn(hdr));
 607         if (fq == NULL) {
 608                 pr_debug("Can't find and can't create new queue\n");
 609                 goto ret_orig;
 610         }
 611
 612         spin_lock_bh(&fq->q.lock);
 613
 614         if (nf_ct_frag6_queue(fq, clone, fhdr, nhoff) < 0) {
 615                 spin_unlock_bh(&fq->q.lock);
 616                 pr_debug("Can't insert skb to queue\n");
 617                 inet_frag_put(&fq->q, &nf_frags);
 618                 goto ret_orig;
 619         }
 620
 621         if (fq->q.flags == (INET_FRAG_FIRST_IN | INET_FRAG_LAST_IN) &&
 622             fq->q.meat == fq->q.len) {
 623                 ret_skb = nf_ct_frag6_reasm(fq, dev);
 624                 if (ret_skb == NULL)
 625                         pr_debug("Can't reassemble fragmented packets\n");
 626         }
 627         spin_unlock_bh(&fq->q.lock);
 628
 629         inet_frag_put(&fq->q, &nf_frags);
 630         return ret_skb;
 631
 632 ret_orig:
 633         kfree_skb(clone);
 634         return skb;
 635 }
 636 EXPORT_SYMBOL_GPL(nf_ct_frag6_gather);
 637
 638 void nf_ct_frag6_consume_orig(struct sk_buff *skb)
 639 {
 640         struct sk_buff *s, *s2;
 641
 642         for (s = NFCT_FRAG6_CB(skb)->orig; s;) {
 643                 s2 = s->next;
 644                 s->next = NULL;
 645                 consume_skb(s);
 646                 s = s2;
 647         }
 648 }
 649 EXPORT_SYMBOL_GPL(nf_ct_frag6_consume_orig);
 650
 651 static int nf_ct_net_init(struct net *net)
 652 {
 653         net->nf_frag.frags.high_thresh = IPV6_FRAG_HIGH_THRESH;
 654         net->nf_frag.frags.low_thresh = IPV6_FRAG_LOW_THRESH;
 655         net->nf_frag.frags.timeout = IPV6_FRAG_TIMEOUT;
 656         inet_frags_init_net(&net->nf_frag.frags);
 657
 658         return nf_ct_frag6_sysctl_register(net);
 659 }
 660
 661 static void nf_ct_net_exit(struct net *net)
 662 {
 663         nf_ct_frags6_sysctl_unregister(net);
 664         inet_frags_exit_net(&net->nf_frag.frags, &nf_frags);
 665 }
 666
 667 static struct pernet_operations nf_ct_net_ops = {
 668         .init = nf_ct_net_init,
 669         .exit = nf_ct_net_exit,
 670 };
 671
 672 int nf_ct_frag6_init(void)
 673 {
 674         int ret = 0;
 675
 676         nf_frags.hashfn = nf_hashfn;
 677         nf_frags.constructor = ip6_frag_init;
 678         nf_frags.destructor = NULL;
 679         nf_frags.skb_free = nf_skb_free;
 680         nf_frags.qsize = sizeof(struct frag_queue);
 681         nf_frags.match = ip6_frag_match;
 682         nf_frags.frag_expire = nf_ct_frag6_expire;
 683         nf_frags.frags_cache_name = nf_frags_cache_name;
 684         ret = inet_frags_init(&nf_frags);
 685         if (ret)
 686                 goto out;
 687         ret = register_pernet_subsys(&nf_ct_net_ops);
 688         if (ret)
 689                 inet_frags_fini(&nf_frags);
 690
 691 out:
 692         return ret;
 693 }
 694
 695 void nf_ct_frag6_cleanup(void)
 696 {
 697         unregister_pernet_subsys(&nf_ct_net_ops);
 698         inet_frags_fini(&nf_frags);
 699 }