1 /* 2 * IPv6 fragment reassembly 3 * Linux INET6 implementation 4 * 5 * Authors: 6 * Pedro Roque <roque@di.fc.ul.pt> 7 * 8 * Based on: net/ipv4/ip_fragment.c 9 * 10 * This program is free software; you can redistribute it and/or 11 * modify it under the terms of the GNU General Public License 12 * as published by the Free Software Foundation; either version 13 * 2 of the License, or (at your option) any later version. 14 */ 15 16 /* 17 * Fixes: 18 * Andi Kleen Make it work with multiple hosts. 19 * More RFC compliance. 20 * 21 * Horst von Brand Add missing #include <linux/string.h> 22 * Alexey Kuznetsov SMP races, threading, cleanup. 23 * Patrick McHardy LRU queue of frag heads for evictor. 24 * Mitsuru KANDA @USAGI Register inet6_protocol{}. 25 * David Stevens and 26 * YOSHIFUJI,H. @USAGI Always remove fragment header to 27 * calculate ICV correctly. 28 */ 29 30 #define pr_fmt(fmt) "IPv6: " fmt 31 32 #include <linux/errno.h> 33 #include <linux/types.h> 34 #include <linux/string.h> 35 #include <linux/socket.h> 36 #include <linux/sockios.h> 37 #include <linux/jiffies.h> 38 #include <linux/net.h> 39 #include <linux/list.h> 40 #include <linux/netdevice.h> 41 #include <linux/in6.h> 42 #include <linux/ipv6.h> 43 #include <linux/icmpv6.h> 44 #include <linux/random.h> 45 #include <linux/jhash.h> 46 #include <linux/skbuff.h> 47 #include <linux/slab.h> 48 #include <linux/export.h> 49 50 #include <net/sock.h> 51 #include <net/snmp.h> 52 53 #include <net/ipv6.h> 54 #include <net/ip6_route.h> 55 #include <net/protocol.h> 56 #include <net/transp_v6.h> 57 #include <net/rawv6.h> 58 #include <net/ndisc.h> 59 #include <net/addrconf.h> 60 #include <net/inet_frag.h> 61 62 struct ip6frag_skb_cb 63 { 64 struct inet6_skb_parm h; 65 int offset; 66 }; 67 68 #define FRAG6_CB(skb) ((struct ip6frag_skb_cb*)((skb)->cb)) 69 70 71 static struct inet_frags ip6_frags; 72 73 static int ip6_frag_reasm(struct frag_queue *fq, struct sk_buff *prev, 74 struct net_device *dev); 75 76 /* 77 * callers should be careful not to use the hash value outside the ipfrag_lock 78 * as doing so could race with ipfrag_hash_rnd being recalculated. 79 */ 80 unsigned int inet6_hash_frag(__be32 id, const struct in6_addr *saddr, 81 const struct in6_addr *daddr, u32 rnd) 82 { 83 u32 c; 84 85 c = jhash_3words(ipv6_addr_hash(saddr), ipv6_addr_hash(daddr), 86 (__force u32)id, rnd); 87 88 return c & (INETFRAGS_HASHSZ - 1); 89 } 90 EXPORT_SYMBOL_GPL(inet6_hash_frag); 91 92 static unsigned int ip6_hashfn(struct inet_frag_queue *q) 93 { 94 struct frag_queue *fq; 95 96 fq = container_of(q, struct frag_queue, q); 97 return inet6_hash_frag(fq->id, &fq->saddr, &fq->daddr, ip6_frags.rnd); 98 } 99 100 bool ip6_frag_match(struct inet_frag_queue *q, void *a) 101 { 102 struct frag_queue *fq; 103 struct ip6_create_arg *arg = a; 104 105 fq = container_of(q, struct frag_queue, q); 106 return fq->id == arg->id && 107 fq->user == arg->user && 108 ipv6_addr_equal(&fq->saddr, arg->src) && 109 ipv6_addr_equal(&fq->daddr, arg->dst); 110 } 111 EXPORT_SYMBOL(ip6_frag_match); 112 113 void ip6_frag_init(struct inet_frag_queue *q, void *a) 114 { 115 struct frag_queue *fq = container_of(q, struct frag_queue, q); 116 struct ip6_create_arg *arg = a; 117 118 fq->id = arg->id; 119 fq->user = arg->user; 120 fq->saddr = *arg->src; 121 fq->daddr = *arg->dst; 122 } 123 EXPORT_SYMBOL(ip6_frag_init); 124 125 void ip6_expire_frag_queue(struct net *net, struct frag_queue *fq, 126 struct inet_frags *frags) 127 { 128 struct net_device *dev = NULL; 129 130 spin_lock(&fq->q.lock); 131 132 if (fq->q.last_in & INET_FRAG_COMPLETE) 133 goto out; 134 135 inet_frag_kill(&fq->q, frags); 136 137 rcu_read_lock(); 138 dev = dev_get_by_index_rcu(net, fq->iif); 139 if (!dev) 140 goto out_rcu_unlock; 141 142 IP6_INC_STATS_BH(net, __in6_dev_get(dev), IPSTATS_MIB_REASMTIMEOUT); 143 IP6_INC_STATS_BH(net, __in6_dev_get(dev), IPSTATS_MIB_REASMFAILS); 144 145 /* Don't send error if the first segment did not arrive. */ 146 if (!(fq->q.last_in & INET_FRAG_FIRST_IN) || !fq->q.fragments) 147 goto out_rcu_unlock; 148 149 /* 150 But use as source device on which LAST ARRIVED 151 segment was received. And do not use fq->dev 152 pointer directly, device might already disappeared. 153 */ 154 fq->q.fragments->dev = dev; 155 icmpv6_send(fq->q.fragments, ICMPV6_TIME_EXCEED, ICMPV6_EXC_FRAGTIME, 0); 156 out_rcu_unlock: 157 rcu_read_unlock(); 158 out: 159 spin_unlock(&fq->q.lock); 160 inet_frag_put(&fq->q, frags); 161 } 162 EXPORT_SYMBOL(ip6_expire_frag_queue); 163 164 static void ip6_frag_expire(unsigned long data) 165 { 166 struct frag_queue *fq; 167 struct net *net; 168 169 fq = container_of((struct inet_frag_queue *)data, struct frag_queue, q); 170 net = container_of(fq->q.net, struct net, ipv6.frags); 171 172 ip6_expire_frag_queue(net, fq, &ip6_frags); 173 } 174 175 static __inline__ struct frag_queue * 176 fq_find(struct net *net, __be32 id, const struct in6_addr *src, const struct in6_addr *dst) 177 { 178 struct inet_frag_queue *q; 179 struct ip6_create_arg arg; 180 unsigned int hash; 181 182 arg.id = id; 183 arg.user = IP6_DEFRAG_LOCAL_DELIVER; 184 arg.src = src; 185 arg.dst = dst; 186 187 read_lock(&ip6_frags.lock); 188 hash = inet6_hash_frag(id, src, dst, ip6_frags.rnd); 189 190 q = inet_frag_find(&net->ipv6.frags, &ip6_frags, &arg, hash); 191 if (IS_ERR_OR_NULL(q)) { 192 inet_frag_maybe_warn_overflow(q, pr_fmt()); 193 return NULL; 194 } 195 return container_of(q, struct frag_queue, q); 196 } 197 198 static int ip6_frag_queue(struct frag_queue *fq, struct sk_buff *skb, 199 struct frag_hdr *fhdr, int nhoff) 200 { 201 struct sk_buff *prev, *next; 202 struct net_device *dev; 203 int offset, end; 204 struct net *net = dev_net(skb_dst(skb)->dev); 205 206 if (fq->q.last_in & INET_FRAG_COMPLETE) 207 goto err; 208 209 offset = ntohs(fhdr->frag_off) & ~0x7; 210 end = offset + (ntohs(ipv6_hdr(skb)->payload_len) - 211 ((u8 *)(fhdr + 1) - (u8 *)(ipv6_hdr(skb) + 1))); 212 213 if ((unsigned int)end > IPV6_MAXPLEN) { 214 IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), 215 IPSTATS_MIB_INHDRERRORS); 216 icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, 217 ((u8 *)&fhdr->frag_off - 218 skb_network_header(skb))); 219 return -1; 220 } 221 222 if (skb->ip_summed == CHECKSUM_COMPLETE) { 223 const unsigned char *nh = skb_network_header(skb); 224 skb->csum = csum_sub(skb->csum, 225 csum_partial(nh, (u8 *)(fhdr + 1) - nh, 226 0)); 227 } 228 229 /* Is this the final fragment? */ 230 if (!(fhdr->frag_off & htons(IP6_MF))) { 231 /* If we already have some bits beyond end 232 * or have different end, the segment is corrupted. 233 */ 234 if (end < fq->q.len || 235 ((fq->q.last_in & INET_FRAG_LAST_IN) && end != fq->q.len)) 236 goto err; 237 fq->q.last_in |= INET_FRAG_LAST_IN; 238 fq->q.len = end; 239 } else { 240 /* Check if the fragment is rounded to 8 bytes. 241 * Required by the RFC. 242 */ 243 if (end & 0x7) { 244 /* RFC2460 says always send parameter problem in 245 * this case. -DaveM 246 */ 247 IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), 248 IPSTATS_MIB_INHDRERRORS); 249 icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, 250 offsetof(struct ipv6hdr, payload_len)); 251 return -1; 252 } 253 if (end > fq->q.len) { 254 /* Some bits beyond end -> corruption. */ 255 if (fq->q.last_in & INET_FRAG_LAST_IN) 256 goto err; 257 fq->q.len = end; 258 } 259 } 260 261 if (end == offset) 262 goto err; 263 264 /* Point into the IP datagram 'data' part. */ 265 if (!pskb_pull(skb, (u8 *) (fhdr + 1) - skb->data)) 266 goto err; 267 268 if (pskb_trim_rcsum(skb, end - offset)) 269 goto err; 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 || 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 (FRAG6_CB(next)->offset >= offset) 283 break; /* bingo! */ 284 prev = next; 285 } 286 287 found: 288 /* RFC5722, Section 4, amended by Errata ID : 3089 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) MUST be silently discarded. 293 */ 294 295 /* Check for overlap with preceding fragment. */ 296 if (prev && 297 (FRAG6_CB(prev)->offset + prev->len) > offset) 298 goto discard_fq; 299 300 /* Look for overlap with succeeding segment. */ 301 if (next && FRAG6_CB(next)->offset < end) 302 goto discard_fq; 303 304 FRAG6_CB(skb)->offset = offset; 305 306 /* Insert this fragment in the chain of fragments. */ 307 skb->next = next; 308 if (!next) 309 fq->q.fragments_tail = skb; 310 if (prev) 311 prev->next = skb; 312 else 313 fq->q.fragments = skb; 314 315 dev = skb->dev; 316 if (dev) { 317 fq->iif = dev->ifindex; 318 skb->dev = NULL; 319 } 320 fq->q.stamp = skb->tstamp; 321 fq->q.meat += skb->len; 322 add_frag_mem_limit(&fq->q, skb->truesize); 323 324 /* The first fragment. 325 * nhoffset is obtained from the first fragment, of course. 326 */ 327 if (offset == 0) { 328 fq->nhoffset = nhoff; 329 fq->q.last_in |= INET_FRAG_FIRST_IN; 330 } 331 332 if (fq->q.last_in == (INET_FRAG_FIRST_IN | INET_FRAG_LAST_IN) && 333 fq->q.meat == fq->q.len) { 334 int res; 335 unsigned long orefdst = skb->_skb_refdst; 336 337 skb->_skb_refdst = 0UL; 338 res = ip6_frag_reasm(fq, prev, dev); 339 skb->_skb_refdst = orefdst; 340 return res; 341 } 342 343 skb_dst_drop(skb); 344 inet_frag_lru_move(&fq->q); 345 return -1; 346 347 discard_fq: 348 inet_frag_kill(&fq->q, &ip6_frags); 349 err: 350 IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), 351 IPSTATS_MIB_REASMFAILS); 352 kfree_skb(skb); 353 return -1; 354 } 355 356 /* 357 * Check if this packet is complete. 358 * Returns NULL on failure by any reason, and pointer 359 * to current nexthdr field in reassembled frame. 360 * 361 * It is called with locked fq, and caller must check that 362 * queue is eligible for reassembly i.e. it is not COMPLETE, 363 * the last and the first frames arrived and all the bits are here. 364 */ 365 static int ip6_frag_reasm(struct frag_queue *fq, struct sk_buff *prev, 366 struct net_device *dev) 367 { 368 struct net *net = container_of(fq->q.net, struct net, ipv6.frags); 369 struct sk_buff *fp, *head = fq->q.fragments; 370 int payload_len; 371 unsigned int nhoff; 372 int sum_truesize; 373 374 inet_frag_kill(&fq->q, &ip6_frags); 375 376 /* Make the one we just received the head. */ 377 if (prev) { 378 head = prev->next; 379 fp = skb_clone(head, GFP_ATOMIC); 380 381 if (!fp) 382 goto out_oom; 383 384 fp->next = head->next; 385 if (!fp->next) 386 fq->q.fragments_tail = fp; 387 prev->next = fp; 388 389 skb_morph(head, fq->q.fragments); 390 head->next = fq->q.fragments->next; 391 392 consume_skb(fq->q.fragments); 393 fq->q.fragments = head; 394 } 395 396 WARN_ON(head == NULL); 397 WARN_ON(FRAG6_CB(head)->offset != 0); 398 399 /* Unfragmented part is taken from the first segment. */ 400 payload_len = ((head->data - skb_network_header(head)) - 401 sizeof(struct ipv6hdr) + fq->q.len - 402 sizeof(struct frag_hdr)); 403 if (payload_len > IPV6_MAXPLEN) 404 goto out_oversize; 405 406 /* Head of list must not be cloned. */ 407 if (skb_unclone(head, GFP_ATOMIC)) 408 goto out_oom; 409 410 /* If the first fragment is fragmented itself, we split 411 * it to two chunks: the first with data and paged part 412 * and the second, holding only fragments. */ 413 if (skb_has_frag_list(head)) { 414 struct sk_buff *clone; 415 int i, plen = 0; 416 417 if ((clone = alloc_skb(0, GFP_ATOMIC)) == NULL) 418 goto out_oom; 419 clone->next = head->next; 420 head->next = clone; 421 skb_shinfo(clone)->frag_list = skb_shinfo(head)->frag_list; 422 skb_frag_list_init(head); 423 for (i = 0; i < skb_shinfo(head)->nr_frags; i++) 424 plen += skb_frag_size(&skb_shinfo(head)->frags[i]); 425 clone->len = clone->data_len = head->data_len - plen; 426 head->data_len -= clone->len; 427 head->len -= clone->len; 428 clone->csum = 0; 429 clone->ip_summed = head->ip_summed; 430 add_frag_mem_limit(&fq->q, clone->truesize); 431 } 432 433 /* We have to remove fragment header from datagram and to relocate 434 * header in order to calculate ICV correctly. */ 435 nhoff = fq->nhoffset; 436 skb_network_header(head)[nhoff] = skb_transport_header(head)[0]; 437 memmove(head->head + sizeof(struct frag_hdr), head->head, 438 (head->data - head->head) - sizeof(struct frag_hdr)); 439 head->mac_header += sizeof(struct frag_hdr); 440 head->network_header += sizeof(struct frag_hdr); 441 442 skb_reset_transport_header(head); 443 skb_push(head, head->data - skb_network_header(head)); 444 445 sum_truesize = head->truesize; 446 for (fp = head->next; fp;) { 447 bool headstolen; 448 int delta; 449 struct sk_buff *next = fp->next; 450 451 sum_truesize += fp->truesize; 452 if (head->ip_summed != fp->ip_summed) 453 head->ip_summed = CHECKSUM_NONE; 454 else if (head->ip_summed == CHECKSUM_COMPLETE) 455 head->csum = csum_add(head->csum, fp->csum); 456 457 if (skb_try_coalesce(head, fp, &headstolen, &delta)) { 458 kfree_skb_partial(fp, headstolen); 459 } else { 460 if (!skb_shinfo(head)->frag_list) 461 skb_shinfo(head)->frag_list = fp; 462 head->data_len += fp->len; 463 head->len += fp->len; 464 head->truesize += fp->truesize; 465 } 466 fp = next; 467 } 468 sub_frag_mem_limit(&fq->q, sum_truesize); 469 470 head->next = NULL; 471 head->dev = dev; 472 head->tstamp = fq->q.stamp; 473 ipv6_hdr(head)->payload_len = htons(payload_len); 474 IP6CB(head)->nhoff = nhoff; 475 476 /* Yes, and fold redundant checksum back. 8) */ 477 if (head->ip_summed == CHECKSUM_COMPLETE) 478 head->csum = csum_partial(skb_network_header(head), 479 skb_network_header_len(head), 480 head->csum); 481 482 rcu_read_lock(); 483 IP6_INC_STATS_BH(net, __in6_dev_get(dev), IPSTATS_MIB_REASMOKS); 484 rcu_read_unlock(); 485 fq->q.fragments = NULL; 486 fq->q.fragments_tail = NULL; 487 return 1; 488 489 out_oversize: 490 net_dbg_ratelimited("ip6_frag_reasm: payload len = %d\n", payload_len); 491 goto out_fail; 492 out_oom: 493 net_dbg_ratelimited("ip6_frag_reasm: no memory for reassembly\n"); 494 out_fail: 495 rcu_read_lock(); 496 IP6_INC_STATS_BH(net, __in6_dev_get(dev), IPSTATS_MIB_REASMFAILS); 497 rcu_read_unlock(); 498 return -1; 499 } 500 501 static int ipv6_frag_rcv(struct sk_buff *skb) 502 { 503 struct frag_hdr *fhdr; 504 struct frag_queue *fq; 505 const struct ipv6hdr *hdr = ipv6_hdr(skb); 506 struct net *net = dev_net(skb_dst(skb)->dev); 507 int evicted; 508 509 IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_REASMREQDS); 510 511 /* Jumbo payload inhibits frag. header */ 512 if (hdr->payload_len==0) 513 goto fail_hdr; 514 515 if (!pskb_may_pull(skb, (skb_transport_offset(skb) + 516 sizeof(struct frag_hdr)))) 517 goto fail_hdr; 518 519 hdr = ipv6_hdr(skb); 520 fhdr = (struct frag_hdr *)skb_transport_header(skb); 521 522 if (!(fhdr->frag_off & htons(0xFFF9))) { 523 /* It is not a fragmented frame */ 524 skb->transport_header += sizeof(struct frag_hdr); 525 IP6_INC_STATS_BH(net, 526 ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_REASMOKS); 527 528 IP6CB(skb)->nhoff = (u8 *)fhdr - skb_network_header(skb); 529 return 1; 530 } 531 532 evicted = inet_frag_evictor(&net->ipv6.frags, &ip6_frags, false); 533 if (evicted) 534 IP6_ADD_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), 535 IPSTATS_MIB_REASMFAILS, evicted); 536 537 fq = fq_find(net, fhdr->identification, &hdr->saddr, &hdr->daddr); 538 if (fq != NULL) { 539 int ret; 540 541 spin_lock(&fq->q.lock); 542 543 ret = ip6_frag_queue(fq, skb, fhdr, IP6CB(skb)->nhoff); 544 545 spin_unlock(&fq->q.lock); 546 inet_frag_put(&fq->q, &ip6_frags); 547 return ret; 548 } 549 550 IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_REASMFAILS); 551 kfree_skb(skb); 552 return -1; 553 554 fail_hdr: 555 IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_INHDRERRORS); 556 icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, skb_network_header_len(skb)); 557 return -1; 558 } 559 560 static const struct inet6_protocol frag_protocol = 561 { 562 .handler = ipv6_frag_rcv, 563 .flags = INET6_PROTO_NOPOLICY, 564 }; 565 566 #ifdef CONFIG_SYSCTL 567 static struct ctl_table ip6_frags_ns_ctl_table[] = { 568 { 569 .procname = "ip6frag_high_thresh", 570 .data = &init_net.ipv6.frags.high_thresh, 571 .maxlen = sizeof(int), 572 .mode = 0644, 573 .proc_handler = proc_dointvec 574 }, 575 { 576 .procname = "ip6frag_low_thresh", 577 .data = &init_net.ipv6.frags.low_thresh, 578 .maxlen = sizeof(int), 579 .mode = 0644, 580 .proc_handler = proc_dointvec 581 }, 582 { 583 .procname = "ip6frag_time", 584 .data = &init_net.ipv6.frags.timeout, 585 .maxlen = sizeof(int), 586 .mode = 0644, 587 .proc_handler = proc_dointvec_jiffies, 588 }, 589 { } 590 }; 591 592 static struct ctl_table ip6_frags_ctl_table[] = { 593 { 594 .procname = "ip6frag_secret_interval", 595 .data = &ip6_frags.secret_interval, 596 .maxlen = sizeof(int), 597 .mode = 0644, 598 .proc_handler = proc_dointvec_jiffies, 599 }, 600 { } 601 }; 602 603 static int __net_init ip6_frags_ns_sysctl_register(struct net *net) 604 { 605 struct ctl_table *table; 606 struct ctl_table_header *hdr; 607 608 table = ip6_frags_ns_ctl_table; 609 if (!net_eq(net, &init_net)) { 610 table = kmemdup(table, sizeof(ip6_frags_ns_ctl_table), GFP_KERNEL); 611 if (table == NULL) 612 goto err_alloc; 613 614 table[0].data = &net->ipv6.frags.high_thresh; 615 table[1].data = &net->ipv6.frags.low_thresh; 616 table[2].data = &net->ipv6.frags.timeout; 617 618 /* Don't export sysctls to unprivileged users */ 619 if (net->user_ns != &init_user_ns) 620 table[0].procname = NULL; 621 } 622 623 hdr = register_net_sysctl(net, "net/ipv6", table); 624 if (hdr == NULL) 625 goto err_reg; 626 627 net->ipv6.sysctl.frags_hdr = hdr; 628 return 0; 629 630 err_reg: 631 if (!net_eq(net, &init_net)) 632 kfree(table); 633 err_alloc: 634 return -ENOMEM; 635 } 636 637 static void __net_exit ip6_frags_ns_sysctl_unregister(struct net *net) 638 { 639 struct ctl_table *table; 640 641 table = net->ipv6.sysctl.frags_hdr->ctl_table_arg; 642 unregister_net_sysctl_table(net->ipv6.sysctl.frags_hdr); 643 if (!net_eq(net, &init_net)) 644 kfree(table); 645 } 646 647 static struct ctl_table_header *ip6_ctl_header; 648 649 static int ip6_frags_sysctl_register(void) 650 { 651 ip6_ctl_header = register_net_sysctl(&init_net, "net/ipv6", 652 ip6_frags_ctl_table); 653 return ip6_ctl_header == NULL ? -ENOMEM : 0; 654 } 655 656 static void ip6_frags_sysctl_unregister(void) 657 { 658 unregister_net_sysctl_table(ip6_ctl_header); 659 } 660 #else 661 static inline int ip6_frags_ns_sysctl_register(struct net *net) 662 { 663 return 0; 664 } 665 666 static inline void ip6_frags_ns_sysctl_unregister(struct net *net) 667 { 668 } 669 670 static inline int ip6_frags_sysctl_register(void) 671 { 672 return 0; 673 } 674 675 static inline void ip6_frags_sysctl_unregister(void) 676 { 677 } 678 #endif 679 680 static int __net_init ipv6_frags_init_net(struct net *net) 681 { 682 net->ipv6.frags.high_thresh = IPV6_FRAG_HIGH_THRESH; 683 net->ipv6.frags.low_thresh = IPV6_FRAG_LOW_THRESH; 684 net->ipv6.frags.timeout = IPV6_FRAG_TIMEOUT; 685 686 inet_frags_init_net(&net->ipv6.frags); 687 688 return ip6_frags_ns_sysctl_register(net); 689 } 690 691 static void __net_exit ipv6_frags_exit_net(struct net *net) 692 { 693 ip6_frags_ns_sysctl_unregister(net); 694 inet_frags_exit_net(&net->ipv6.frags, &ip6_frags); 695 } 696 697 static struct pernet_operations ip6_frags_ops = { 698 .init = ipv6_frags_init_net, 699 .exit = ipv6_frags_exit_net, 700 }; 701 702 int __init ipv6_frag_init(void) 703 { 704 int ret; 705 706 ret = inet6_add_protocol(&frag_protocol, IPPROTO_FRAGMENT); 707 if (ret) 708 goto out; 709 710 ret = ip6_frags_sysctl_register(); 711 if (ret) 712 goto err_sysctl; 713 714 ret = register_pernet_subsys(&ip6_frags_ops); 715 if (ret) 716 goto err_pernet; 717 718 ip6_frags.hashfn = ip6_hashfn; 719 ip6_frags.constructor = ip6_frag_init; 720 ip6_frags.destructor = NULL; 721 ip6_frags.skb_free = NULL; 722 ip6_frags.qsize = sizeof(struct frag_queue); 723 ip6_frags.match = ip6_frag_match; 724 ip6_frags.frag_expire = ip6_frag_expire; 725 ip6_frags.secret_interval = 10 * 60 * HZ; 726 inet_frags_init(&ip6_frags); 727 out: 728 return ret; 729 730 err_pernet: 731 ip6_frags_sysctl_unregister(); 732 err_sysctl: 733 inet6_del_protocol(&frag_protocol, IPPROTO_FRAGMENT); 734 goto out; 735 } 736 737 void ipv6_frag_exit(void) 738 { 739 inet_frags_fini(&ip6_frags); 740 ip6_frags_sysctl_unregister(); 741 unregister_pernet_subsys(&ip6_frags_ops); 742 inet6_del_protocol(&frag_protocol, IPPROTO_FRAGMENT); 743 } 744