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   1 /*
   2  *      IPv6 fragment reassembly
   3  *      Linux INET6 implementation
   4  *
   5  *      Authors:
   6  *      Pedro Roque             <roque@di.fc.ul.pt>
   7  *
   8  *      $Id: reassembly.c,v 1.26 2001/03/07 22:00:57 davem Exp $
   9  *
  10  *      Based on: net/ipv4/ip_fragment.c
  11  *
  12  *      This program is free software; you can redistribute it and/or
  13  *      modify it under the terms of the GNU General Public License
  14  *      as published by the Free Software Foundation; either version
  15  *      2 of the License, or (at your option) any later version.
  16  */
  17
  18 /*
  19  *      Fixes:
  20  *      Andi Kleen      Make it work with multiple hosts.
  21  *                      More RFC compliance.
  22  *
  23  *      Horst von Brand Add missing #include <linux/string.h>
  24  *      Alexey Kuznetsov        SMP races, threading, cleanup.
  25  *      Patrick McHardy         LRU queue of frag heads for evictor.
  26  *      Mitsuru KANDA @USAGI    Register inet6_protocol{}.
  27  *      David Stevens and
  28  *      YOSHIFUJI,H. @USAGI     Always remove fragment header to
  29  *                              calculate ICV correctly.
  30  */
  31 #include <linux/errno.h>
  32 #include <linux/types.h>
  33 #include <linux/string.h>
  34 #include <linux/socket.h>
  35 #include <linux/sockios.h>
  36 #include <linux/jiffies.h>
  37 #include <linux/net.h>
  38 #include <linux/list.h>
  39 #include <linux/netdevice.h>
  40 #include <linux/in6.h>
  41 #include <linux/ipv6.h>
  42 #include <linux/icmpv6.h>
  43 #include <linux/random.h>
  44 #include <linux/jhash.h>
  45 #include <linux/skbuff.h>
  46
  47 #include <net/sock.h>
  48 #include <net/snmp.h>
  49
  50 #include <net/ipv6.h>
  51 #include <net/ip6_route.h>
  52 #include <net/protocol.h>
  53 #include <net/transp_v6.h>
  54 #include <net/rawv6.h>
  55 #include <net/ndisc.h>
  56 #include <net/addrconf.h>
  57 #include <net/inet_frag.h>
  58
  59 struct ip6frag_skb_cb
  60 {
  61         struct inet6_skb_parm   h;
  62         int                     offset;
  63 };
  64
  65 #define FRAG6_CB(skb)   ((struct ip6frag_skb_cb*)((skb)->cb))
  66
  67
  68 /*
  69  *      Equivalent of ipv4 struct ipq
  70  */
  71
  72 struct frag_queue
  73 {
  74         struct inet_frag_queue  q;
  75
  76         __be32                  id;             /* fragment id          */
  77         struct in6_addr         saddr;
  78         struct in6_addr         daddr;
  79
  80         int                     iif;
  81         unsigned int            csum;
  82         __u16                   nhoffset;
  83 };
  84
  85 struct inet_frags_ctl ip6_frags_ctl __read_mostly = {
  86         .high_thresh     = 256 * 1024,
  87         .low_thresh      = 192 * 1024,
  88         .timeout         = IPV6_FRAG_TIMEOUT,
  89         .secret_interval = 10 * 60 * HZ,
  90 };
  91
  92 static struct inet_frags ip6_frags;
  93
  94 int ip6_frag_nqueues(void)
  95 {
  96         return ip6_frags.nqueues;
  97 }
  98
  99 int ip6_frag_mem(void)
 100 {
 101         return atomic_read(&ip6_frags.mem);
 102 }
 103
 104 static int ip6_frag_reasm(struct frag_queue *fq, struct sk_buff *prev,
 105                           struct net_device *dev);
 106
 107 /*
 108  * callers should be careful not to use the hash value outside the ipfrag_lock
 109  * as doing so could race with ipfrag_hash_rnd being recalculated.
 110  */
 111 static unsigned int ip6qhashfn(__be32 id, struct in6_addr *saddr,
 112                                struct in6_addr *daddr)
 113 {
 114         u32 a, b, c;
 115
 116         a = (__force u32)saddr->s6_addr32[0];
 117         b = (__force u32)saddr->s6_addr32[1];
 118         c = (__force u32)saddr->s6_addr32[2];
 119
 120         a += JHASH_GOLDEN_RATIO;
 121         b += JHASH_GOLDEN_RATIO;
 122         c += ip6_frags.rnd;
 123         __jhash_mix(a, b, c);
 124
 125         a += (__force u32)saddr->s6_addr32[3];
 126         b += (__force u32)daddr->s6_addr32[0];
 127         c += (__force u32)daddr->s6_addr32[1];
 128         __jhash_mix(a, b, c);
 129
 130         a += (__force u32)daddr->s6_addr32[2];
 131         b += (__force u32)daddr->s6_addr32[3];
 132         c += (__force u32)id;
 133         __jhash_mix(a, b, c);
 134
 135         return c & (INETFRAGS_HASHSZ - 1);
 136 }
 137
 138 static unsigned int ip6_hashfn(struct inet_frag_queue *q)
 139 {
 140         struct frag_queue *fq;
 141
 142         fq = container_of(q, struct frag_queue, q);
 143         return ip6qhashfn(fq->id, &fq->saddr, &fq->daddr);
 144 }
 145
 146 int ip6_frag_match(struct inet_frag_queue *q, void *a)
 147 {
 148         struct frag_queue *fq;
 149         struct ip6_create_arg *arg = a;
 150
 151         fq = container_of(q, struct frag_queue, q);
 152         return (fq->id == arg->id &&
 153                         ipv6_addr_equal(&fq->saddr, arg->src) &&
 154                         ipv6_addr_equal(&fq->daddr, arg->dst));
 155 }
 156 EXPORT_SYMBOL(ip6_frag_match);
 157
 158 /* Memory Tracking Functions. */
 159 static inline void frag_kfree_skb(struct sk_buff *skb, int *work)
 160 {
 161         if (work)
 162                 *work -= skb->truesize;
 163         atomic_sub(skb->truesize, &ip6_frags.mem);
 164         kfree_skb(skb);
 165 }
 166
 167 void ip6_frag_init(struct inet_frag_queue *q, void *a)
 168 {
 169         struct frag_queue *fq = container_of(q, struct frag_queue, q);
 170         struct ip6_create_arg *arg = a;
 171
 172         fq->id = arg->id;
 173         ipv6_addr_copy(&fq->saddr, arg->src);
 174         ipv6_addr_copy(&fq->daddr, arg->dst);
 175 }
 176 EXPORT_SYMBOL(ip6_frag_init);
 177
 178 static void ip6_frag_free(struct inet_frag_queue *fq)
 179 {
 180         kfree(container_of(fq, struct frag_queue, q));
 181 }
 182
 183 /* Destruction primitives. */
 184
 185 static __inline__ void fq_put(struct frag_queue *fq)
 186 {
 187         inet_frag_put(&fq->q, &ip6_frags);
 188 }
 189
 190 /* Kill fq entry. It is not destroyed immediately,
 191  * because caller (and someone more) holds reference count.
 192  */
 193 static __inline__ void fq_kill(struct frag_queue *fq)
 194 {
 195         inet_frag_kill(&fq->q, &ip6_frags);
 196 }
 197
 198 static void ip6_evictor(struct inet6_dev *idev)
 199 {
 200         int evicted;
 201
 202         evicted = inet_frag_evictor(&ip6_frags);
 203         if (evicted)
 204                 IP6_ADD_STATS_BH(idev, IPSTATS_MIB_REASMFAILS, evicted);
 205 }
 206
 207 static void ip6_frag_expire(unsigned long data)
 208 {
 209         struct frag_queue *fq;
 210         struct net_device *dev = NULL;
 211
 212         fq = container_of((struct inet_frag_queue *)data, struct frag_queue, q);
 213
 214         spin_lock(&fq->q.lock);
 215
 216         if (fq->q.last_in & COMPLETE)
 217                 goto out;
 218
 219         fq_kill(fq);
 220
 221         dev = dev_get_by_index(&init_net, fq->iif);
 222         if (!dev)
 223                 goto out;
 224
 225         rcu_read_lock();
 226         IP6_INC_STATS_BH(__in6_dev_get(dev), IPSTATS_MIB_REASMTIMEOUT);
 227         IP6_INC_STATS_BH(__in6_dev_get(dev), IPSTATS_MIB_REASMFAILS);
 228         rcu_read_unlock();
 229
 230         /* Don't send error if the first segment did not arrive. */
 231         if (!(fq->q.last_in&FIRST_IN) || !fq->q.fragments)
 232                 goto out;
 233
 234         /*
 235            But use as source device on which LAST ARRIVED
 236            segment was received. And do not use fq->dev
 237            pointer directly, device might already disappeared.
 238          */
 239         fq->q.fragments->dev = dev;
 240         icmpv6_send(fq->q.fragments, ICMPV6_TIME_EXCEED, ICMPV6_EXC_FRAGTIME, 0, dev);
 241 out:
 242         if (dev)
 243                 dev_put(dev);
 244         spin_unlock(&fq->q.lock);
 245         fq_put(fq);
 246 }
 247
 248 static __inline__ struct frag_queue *
 249 fq_find(__be32 id, struct in6_addr *src, struct in6_addr *dst,
 250         struct inet6_dev *idev)
 251 {
 252         struct inet_frag_queue *q;
 253         struct ip6_create_arg arg;
 254         unsigned int hash;
 255
 256         arg.id = id;
 257         arg.src = src;
 258         arg.dst = dst;
 259         hash = ip6qhashfn(id, src, dst);
 260
 261         q = inet_frag_find(&ip6_frags, &arg, hash);
 262         if (q == NULL)
 263                 goto oom;
 264
 265         return container_of(q, struct frag_queue, q);
 266
 267 oom:
 268         IP6_INC_STATS_BH(idev, IPSTATS_MIB_REASMFAILS);
 269         return NULL;
 270 }
 271
 272 static int ip6_frag_queue(struct frag_queue *fq, struct sk_buff *skb,
 273                            struct frag_hdr *fhdr, int nhoff)
 274 {
 275         struct sk_buff *prev, *next;
 276         struct net_device *dev;
 277         int offset, end;
 278
 279         if (fq->q.last_in & COMPLETE)
 280                 goto err;
 281
 282         offset = ntohs(fhdr->frag_off) & ~0x7;
 283         end = offset + (ntohs(ipv6_hdr(skb)->payload_len) -
 284                         ((u8 *)(fhdr + 1) - (u8 *)(ipv6_hdr(skb) + 1)));
 285
 286         if ((unsigned int)end > IPV6_MAXPLEN) {
 287                 IP6_INC_STATS_BH(ip6_dst_idev(skb->dst),
 288                                  IPSTATS_MIB_INHDRERRORS);
 289                 icmpv6_param_prob(skb, ICMPV6_HDR_FIELD,
 290                                   ((u8 *)&fhdr->frag_off -
 291                                    skb_network_header(skb)));
 292                 return -1;
 293         }
 294
 295         if (skb->ip_summed == CHECKSUM_COMPLETE) {
 296                 const unsigned char *nh = skb_network_header(skb);
 297                 skb->csum = csum_sub(skb->csum,
 298                                      csum_partial(nh, (u8 *)(fhdr + 1) - nh,
 299                                                   0));
 300         }
 301
 302         /* Is this the final fragment? */
 303         if (!(fhdr->frag_off & htons(IP6_MF))) {
 304                 /* If we already have some bits beyond end
 305                  * or have different end, the segment is corrupted.
 306                  */
 307                 if (end < fq->q.len ||
 308                     ((fq->q.last_in & LAST_IN) && end != fq->q.len))
 309                         goto err;
 310                 fq->q.last_in |= LAST_IN;
 311                 fq->q.len = end;
 312         } else {
 313                 /* Check if the fragment is rounded to 8 bytes.
 314                  * Required by the RFC.
 315                  */
 316                 if (end & 0x7) {
 317                         /* RFC2460 says always send parameter problem in
 318                          * this case. -DaveM
 319                          */
 320                         IP6_INC_STATS_BH(ip6_dst_idev(skb->dst),
 321                                          IPSTATS_MIB_INHDRERRORS);
 322                         icmpv6_param_prob(skb, ICMPV6_HDR_FIELD,
 323                                           offsetof(struct ipv6hdr, payload_len));
 324                         return -1;
 325                 }
 326                 if (end > fq->q.len) {
 327                         /* Some bits beyond end -> corruption. */
 328                         if (fq->q.last_in & LAST_IN)
 329                                 goto err;
 330                         fq->q.len = end;
 331                 }
 332         }
 333
 334         if (end == offset)
 335                 goto err;
 336
 337         /* Point into the IP datagram 'data' part. */
 338         if (!pskb_pull(skb, (u8 *) (fhdr + 1) - skb->data))
 339                 goto err;
 340
 341         if (pskb_trim_rcsum(skb, end - offset))
 342                 goto err;
 343
 344         /* Find out which fragments are in front and at the back of us
 345          * in the chain of fragments so far.  We must know where to put
 346          * this fragment, right?
 347          */
 348         prev = NULL;
 349         for(next = fq->q.fragments; next != NULL; next = next->next) {
 350                 if (FRAG6_CB(next)->offset >= offset)
 351                         break;  /* bingo! */
 352                 prev = next;
 353         }
 354
 355         /* We found where to put this one.  Check for overlap with
 356          * preceding fragment, and, if needed, align things so that
 357          * any overlaps are eliminated.
 358          */
 359         if (prev) {
 360                 int i = (FRAG6_CB(prev)->offset + prev->len) - offset;
 361
 362                 if (i > 0) {
 363                         offset += i;
 364                         if (end <= offset)
 365                                 goto err;
 366                         if (!pskb_pull(skb, i))
 367                                 goto err;
 368                         if (skb->ip_summed != CHECKSUM_UNNECESSARY)
 369                                 skb->ip_summed = CHECKSUM_NONE;
 370                 }
 371         }
 372
 373         /* Look for overlap with succeeding segments.
 374          * If we can merge fragments, do it.
 375          */
 376         while (next && FRAG6_CB(next)->offset < end) {
 377                 int i = end - FRAG6_CB(next)->offset; /* overlap is 'i' bytes */
 378
 379                 if (i < next->len) {
 380                         /* Eat head of the next overlapped fragment
 381                          * and leave the loop. The next ones cannot overlap.
 382                          */
 383                         if (!pskb_pull(next, i))
 384                                 goto err;
 385                         FRAG6_CB(next)->offset += i;    /* next fragment */
 386                         fq->q.meat -= i;
 387                         if (next->ip_summed != CHECKSUM_UNNECESSARY)
 388                                 next->ip_summed = CHECKSUM_NONE;
 389                         break;
 390                 } else {
 391                         struct sk_buff *free_it = next;
 392
 393                         /* Old fragment is completely overridden with
 394                          * new one drop it.
 395                          */
 396                         next = next->next;
 397
 398                         if (prev)
 399                                 prev->next = next;
 400                         else
 401                                 fq->q.fragments = next;
 402
 403                         fq->q.meat -= free_it->len;
 404                         frag_kfree_skb(free_it, NULL);
 405                 }
 406         }
 407
 408         FRAG6_CB(skb)->offset = offset;
 409
 410         /* Insert this fragment in the chain of fragments. */
 411         skb->next = next;
 412         if (prev)
 413                 prev->next = skb;
 414         else
 415                 fq->q.fragments = skb;
 416
 417         dev = skb->dev;
 418         if (dev) {
 419                 fq->iif = dev->ifindex;
 420                 skb->dev = NULL;
 421         }
 422         fq->q.stamp = skb->tstamp;
 423         fq->q.meat += skb->len;
 424         atomic_add(skb->truesize, &ip6_frags.mem);
 425
 426         /* The first fragment.
 427          * nhoffset is obtained from the first fragment, of course.
 428          */
 429         if (offset == 0) {
 430                 fq->nhoffset = nhoff;
 431                 fq->q.last_in |= FIRST_IN;
 432         }
 433
 434         if (fq->q.last_in == (FIRST_IN | LAST_IN) && fq->q.meat == fq->q.len)
 435                 return ip6_frag_reasm(fq, prev, dev);
 436
 437         write_lock(&ip6_frags.lock);
 438         list_move_tail(&fq->q.lru_list, &ip6_frags.lru_list);
 439         write_unlock(&ip6_frags.lock);
 440         return -1;
 441
 442 err:
 443         IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_REASMFAILS);
 444         kfree_skb(skb);
 445         return -1;
 446 }
 447
 448 /*
 449  *      Check if this packet is complete.
 450  *      Returns NULL on failure by any reason, and pointer
 451  *      to current nexthdr field in reassembled frame.
 452  *
 453  *      It is called with locked fq, and caller must check that
 454  *      queue is eligible for reassembly i.e. it is not COMPLETE,
 455  *      the last and the first frames arrived and all the bits are here.
 456  */
 457 static int ip6_frag_reasm(struct frag_queue *fq, struct sk_buff *prev,
 458                           struct net_device *dev)
 459 {
 460         struct sk_buff *fp, *head = fq->q.fragments;
 461         int    payload_len;
 462         unsigned int nhoff;
 463
 464         fq_kill(fq);
 465
 466         /* Make the one we just received the head. */
 467         if (prev) {
 468                 head = prev->next;
 469                 fp = skb_clone(head, GFP_ATOMIC);
 470
 471                 if (!fp)
 472                         goto out_oom;
 473
 474                 fp->next = head->next;
 475                 prev->next = fp;
 476
 477                 skb_morph(head, fq->q.fragments);
 478                 head->next = fq->q.fragments->next;
 479
 480                 kfree_skb(fq->q.fragments);
 481                 fq->q.fragments = head;
 482         }
 483
 484         BUG_TRAP(head != NULL);
 485         BUG_TRAP(FRAG6_CB(head)->offset == 0);
 486
 487         /* Unfragmented part is taken from the first segment. */
 488         payload_len = ((head->data - skb_network_header(head)) -
 489                        sizeof(struct ipv6hdr) + fq->q.len -
 490                        sizeof(struct frag_hdr));
 491         if (payload_len > IPV6_MAXPLEN)
 492                 goto out_oversize;
 493
 494         /* Head of list must not be cloned. */
 495         if (skb_cloned(head) && pskb_expand_head(head, 0, 0, GFP_ATOMIC))
 496                 goto out_oom;
 497
 498         /* If the first fragment is fragmented itself, we split
 499          * it to two chunks: the first with data and paged part
 500          * and the second, holding only fragments. */
 501         if (skb_shinfo(head)->frag_list) {
 502                 struct sk_buff *clone;
 503                 int i, plen = 0;
 504
 505                 if ((clone = alloc_skb(0, GFP_ATOMIC)) == NULL)
 506                         goto out_oom;
 507                 clone->next = head->next;
 508                 head->next = clone;
 509                 skb_shinfo(clone)->frag_list = skb_shinfo(head)->frag_list;
 510                 skb_shinfo(head)->frag_list = NULL;
 511                 for (i=0; i<skb_shinfo(head)->nr_frags; i++)
 512                         plen += skb_shinfo(head)->frags[i].size;
 513                 clone->len = clone->data_len = head->data_len - plen;
 514                 head->data_len -= clone->len;
 515                 head->len -= clone->len;
 516                 clone->csum = 0;
 517                 clone->ip_summed = head->ip_summed;
 518                 atomic_add(clone->truesize, &ip6_frags.mem);
 519         }
 520
 521         /* We have to remove fragment header from datagram and to relocate
 522          * header in order to calculate ICV correctly. */
 523         nhoff = fq->nhoffset;
 524         skb_network_header(head)[nhoff] = skb_transport_header(head)[0];
 525         memmove(head->head + sizeof(struct frag_hdr), head->head,
 526                 (head->data - head->head) - sizeof(struct frag_hdr));
 527         head->mac_header += sizeof(struct frag_hdr);
 528         head->network_header += sizeof(struct frag_hdr);
 529
 530         skb_shinfo(head)->frag_list = head->next;
 531         skb_reset_transport_header(head);
 532         skb_push(head, head->data - skb_network_header(head));
 533         atomic_sub(head->truesize, &ip6_frags.mem);
 534
 535         for (fp=head->next; fp; fp = fp->next) {
 536                 head->data_len += fp->len;
 537                 head->len += fp->len;
 538                 if (head->ip_summed != fp->ip_summed)
 539                         head->ip_summed = CHECKSUM_NONE;
 540                 else if (head->ip_summed == CHECKSUM_COMPLETE)
 541                         head->csum = csum_add(head->csum, fp->csum);
 542                 head->truesize += fp->truesize;
 543                 atomic_sub(fp->truesize, &ip6_frags.mem);
 544         }
 545
 546         head->next = NULL;
 547         head->dev = dev;
 548         head->tstamp = fq->q.stamp;
 549         ipv6_hdr(head)->payload_len = htons(payload_len);
 550         IP6CB(head)->nhoff = nhoff;
 551
 552         /* Yes, and fold redundant checksum back. 8) */
 553         if (head->ip_summed == CHECKSUM_COMPLETE)
 554                 head->csum = csum_partial(skb_network_header(head),
 555                                           skb_network_header_len(head),
 556                                           head->csum);
 557
 558         rcu_read_lock();
 559         IP6_INC_STATS_BH(__in6_dev_get(dev), IPSTATS_MIB_REASMOKS);
 560         rcu_read_unlock();
 561         fq->q.fragments = NULL;
 562         return 1;
 563
 564 out_oversize:
 565         if (net_ratelimit())
 566                 printk(KERN_DEBUG "ip6_frag_reasm: payload len = %d\n", payload_len);
 567         goto out_fail;
 568 out_oom:
 569         if (net_ratelimit())
 570                 printk(KERN_DEBUG "ip6_frag_reasm: no memory for reassembly\n");
 571 out_fail:
 572         rcu_read_lock();
 573         IP6_INC_STATS_BH(__in6_dev_get(dev), IPSTATS_MIB_REASMFAILS);
 574         rcu_read_unlock();
 575         return -1;
 576 }
 577
 578 static int ipv6_frag_rcv(struct sk_buff *skb)
 579 {
 580         struct frag_hdr *fhdr;
 581         struct frag_queue *fq;
 582         struct ipv6hdr *hdr = ipv6_hdr(skb);
 583
 584         IP6_INC_STATS_BH(ip6_dst_idev(skb->dst), IPSTATS_MIB_REASMREQDS);
 585
 586         /* Jumbo payload inhibits frag. header */
 587         if (hdr->payload_len==0) {
 588                 IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_INHDRERRORS);
 589                 icmpv6_param_prob(skb, ICMPV6_HDR_FIELD,
 590                                   skb_network_header_len(skb));
 591                 return -1;
 592         }
 593         if (!pskb_may_pull(skb, (skb_transport_offset(skb) +
 594                                  sizeof(struct frag_hdr)))) {
 595                 IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_INHDRERRORS);
 596                 icmpv6_param_prob(skb, ICMPV6_HDR_FIELD,
 597                                   skb_network_header_len(skb));
 598                 return -1;
 599         }
 600
 601         hdr = ipv6_hdr(skb);
 602         fhdr = (struct frag_hdr *)skb_transport_header(skb);
 603
 604         if (!(fhdr->frag_off & htons(0xFFF9))) {
 605                 /* It is not a fragmented frame */
 606                 skb->transport_header += sizeof(struct frag_hdr);
 607                 IP6_INC_STATS_BH(ip6_dst_idev(skb->dst), IPSTATS_MIB_REASMOKS);
 608
 609                 IP6CB(skb)->nhoff = (u8 *)fhdr - skb_network_header(skb);
 610                 return 1;
 611         }
 612
 613         if (atomic_read(&ip6_frags.mem) > ip6_frags_ctl.high_thresh)
 614                 ip6_evictor(ip6_dst_idev(skb->dst));
 615
 616         if ((fq = fq_find(fhdr->identification, &hdr->saddr, &hdr->daddr,
 617                           ip6_dst_idev(skb->dst))) != NULL) {
 618                 int ret;
 619
 620                 spin_lock(&fq->q.lock);
 621
 622                 ret = ip6_frag_queue(fq, skb, fhdr, IP6CB(skb)->nhoff);
 623
 624                 spin_unlock(&fq->q.lock);
 625                 fq_put(fq);
 626                 return ret;
 627         }
 628
 629         IP6_INC_STATS_BH(ip6_dst_idev(skb->dst), IPSTATS_MIB_REASMFAILS);
 630         kfree_skb(skb);
 631         return -1;
 632 }
 633
 634 static struct inet6_protocol frag_protocol =
 635 {
 636         .handler        =       ipv6_frag_rcv,
 637         .flags          =       INET6_PROTO_NOPOLICY,
 638 };
 639
 640 void __init ipv6_frag_init(void)
 641 {
 642         if (inet6_add_protocol(&frag_protocol, IPPROTO_FRAGMENT) < 0)
 643                 printk(KERN_ERR "ipv6_frag_init: Could not register protocol\n");
 644
 645         ip6_frags.ctl = &ip6_frags_ctl;
 646         ip6_frags.hashfn = ip6_hashfn;
 647         ip6_frags.constructor = ip6_frag_init;
 648         ip6_frags.destructor = ip6_frag_free;
 649         ip6_frags.skb_free = NULL;
 650         ip6_frags.qsize = sizeof(struct frag_queue);
 651         ip6_frags.match = ip6_frag_match;
 652         ip6_frags.frag_expire = ip6_frag_expire;
 653         inet_frags_init(&ip6_frags);
 654 }