1 /* 2 * IPv6 tunneling device 3 * Linux INET6 implementation 4 * 5 * Authors: 6 * Ville Nuorvala <vnuorval@tcs.hut.fi> 7 * Yasuyuki Kozakai <kozakai@linux-ipv6.org> 8 * 9 * Based on: 10 * linux/net/ipv6/sit.c and linux/net/ipv4/ipip.c 11 * 12 * RFC 2473 13 * 14 * This program is free software; you can redistribute it and/or 15 * modify it under the terms of the GNU General Public License 16 * as published by the Free Software Foundation; either version 17 * 2 of the License, or (at your option) any later version. 18 * 19 */ 20 21 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 22 23 #include <linux/module.h> 24 #include <linux/capability.h> 25 #include <linux/errno.h> 26 #include <linux/types.h> 27 #include <linux/sockios.h> 28 #include <linux/icmp.h> 29 #include <linux/if.h> 30 #include <linux/in.h> 31 #include <linux/ip.h> 32 #include <linux/net.h> 33 #include <linux/in6.h> 34 #include <linux/netdevice.h> 35 #include <linux/if_arp.h> 36 #include <linux/icmpv6.h> 37 #include <linux/init.h> 38 #include <linux/route.h> 39 #include <linux/rtnetlink.h> 40 #include <linux/netfilter_ipv6.h> 41 #include <linux/slab.h> 42 #include <linux/hash.h> 43 #include <linux/etherdevice.h> 44 45 #include <asm/uaccess.h> 46 #include <linux/atomic.h> 47 48 #include <net/icmp.h> 49 #include <net/ip.h> 50 #include <net/ip_tunnels.h> 51 #include <net/ipv6.h> 52 #include <net/ip6_route.h> 53 #include <net/addrconf.h> 54 #include <net/ip6_tunnel.h> 55 #include <net/xfrm.h> 56 #include <net/dsfield.h> 57 #include <net/inet_ecn.h> 58 #include <net/net_namespace.h> 59 #include <net/netns/generic.h> 60 61 MODULE_AUTHOR("Ville Nuorvala"); 62 MODULE_DESCRIPTION("IPv6 tunneling device"); 63 MODULE_LICENSE("GPL"); 64 MODULE_ALIAS_RTNL_LINK("ip6tnl"); 65 MODULE_ALIAS_NETDEV("ip6tnl0"); 66 67 #define HASH_SIZE_SHIFT 5 68 #define HASH_SIZE (1 << HASH_SIZE_SHIFT) 69 70 static bool log_ecn_error = true; 71 module_param(log_ecn_error, bool, 0644); 72 MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN"); 73 74 static u32 HASH(const struct in6_addr *addr1, const struct in6_addr *addr2) 75 { 76 u32 hash = ipv6_addr_hash(addr1) ^ ipv6_addr_hash(addr2); 77 78 return hash_32(hash, HASH_SIZE_SHIFT); 79 } 80 81 static int ip6_tnl_dev_init(struct net_device *dev); 82 static void ip6_tnl_dev_setup(struct net_device *dev); 83 static struct rtnl_link_ops ip6_link_ops __read_mostly; 84 85 static int ip6_tnl_net_id __read_mostly; 86 struct ip6_tnl_net { 87 /* the IPv6 tunnel fallback device */ 88 struct net_device *fb_tnl_dev; 89 /* lists for storing tunnels in use */ 90 struct ip6_tnl __rcu *tnls_r_l[HASH_SIZE]; 91 struct ip6_tnl __rcu *tnls_wc[1]; 92 struct ip6_tnl __rcu **tnls[2]; 93 }; 94 95 static struct net_device_stats *ip6_get_stats(struct net_device *dev) 96 { 97 struct pcpu_sw_netstats tmp, sum = { 0 }; 98 int i; 99 100 for_each_possible_cpu(i) { 101 unsigned int start; 102 const struct pcpu_sw_netstats *tstats = 103 per_cpu_ptr(dev->tstats, i); 104 105 do { 106 start = u64_stats_fetch_begin_irq(&tstats->syncp); 107 tmp.rx_packets = tstats->rx_packets; 108 tmp.rx_bytes = tstats->rx_bytes; 109 tmp.tx_packets = tstats->tx_packets; 110 tmp.tx_bytes = tstats->tx_bytes; 111 } while (u64_stats_fetch_retry_irq(&tstats->syncp, start)); 112 113 sum.rx_packets += tmp.rx_packets; 114 sum.rx_bytes += tmp.rx_bytes; 115 sum.tx_packets += tmp.tx_packets; 116 sum.tx_bytes += tmp.tx_bytes; 117 } 118 dev->stats.rx_packets = sum.rx_packets; 119 dev->stats.rx_bytes = sum.rx_bytes; 120 dev->stats.tx_packets = sum.tx_packets; 121 dev->stats.tx_bytes = sum.tx_bytes; 122 return &dev->stats; 123 } 124 125 /** 126 * ip6_tnl_lookup - fetch tunnel matching the end-point addresses 127 * @remote: the address of the tunnel exit-point 128 * @local: the address of the tunnel entry-point 129 * 130 * Return: 131 * tunnel matching given end-points if found, 132 * else fallback tunnel if its device is up, 133 * else %NULL 134 **/ 135 136 #define for_each_ip6_tunnel_rcu(start) \ 137 for (t = rcu_dereference(start); t; t = rcu_dereference(t->next)) 138 139 static struct ip6_tnl * 140 ip6_tnl_lookup(struct net *net, const struct in6_addr *remote, const struct in6_addr *local) 141 { 142 unsigned int hash = HASH(remote, local); 143 struct ip6_tnl *t; 144 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 145 struct in6_addr any; 146 147 for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) { 148 if (ipv6_addr_equal(local, &t->parms.laddr) && 149 ipv6_addr_equal(remote, &t->parms.raddr) && 150 (t->dev->flags & IFF_UP)) 151 return t; 152 } 153 154 memset(&any, 0, sizeof(any)); 155 hash = HASH(&any, local); 156 for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) { 157 if (ipv6_addr_equal(local, &t->parms.laddr) && 158 (t->dev->flags & IFF_UP)) 159 return t; 160 } 161 162 hash = HASH(remote, &any); 163 for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) { 164 if (ipv6_addr_equal(remote, &t->parms.raddr) && 165 (t->dev->flags & IFF_UP)) 166 return t; 167 } 168 169 t = rcu_dereference(ip6n->tnls_wc[0]); 170 if (t && (t->dev->flags & IFF_UP)) 171 return t; 172 173 return NULL; 174 } 175 176 /** 177 * ip6_tnl_bucket - get head of list matching given tunnel parameters 178 * @p: parameters containing tunnel end-points 179 * 180 * Description: 181 * ip6_tnl_bucket() returns the head of the list matching the 182 * &struct in6_addr entries laddr and raddr in @p. 183 * 184 * Return: head of IPv6 tunnel list 185 **/ 186 187 static struct ip6_tnl __rcu ** 188 ip6_tnl_bucket(struct ip6_tnl_net *ip6n, const struct __ip6_tnl_parm *p) 189 { 190 const struct in6_addr *remote = &p->raddr; 191 const struct in6_addr *local = &p->laddr; 192 unsigned int h = 0; 193 int prio = 0; 194 195 if (!ipv6_addr_any(remote) || !ipv6_addr_any(local)) { 196 prio = 1; 197 h = HASH(remote, local); 198 } 199 return &ip6n->tnls[prio][h]; 200 } 201 202 /** 203 * ip6_tnl_link - add tunnel to hash table 204 * @t: tunnel to be added 205 **/ 206 207 static void 208 ip6_tnl_link(struct ip6_tnl_net *ip6n, struct ip6_tnl *t) 209 { 210 struct ip6_tnl __rcu **tp = ip6_tnl_bucket(ip6n, &t->parms); 211 212 rcu_assign_pointer(t->next , rtnl_dereference(*tp)); 213 rcu_assign_pointer(*tp, t); 214 } 215 216 /** 217 * ip6_tnl_unlink - remove tunnel from hash table 218 * @t: tunnel to be removed 219 **/ 220 221 static void 222 ip6_tnl_unlink(struct ip6_tnl_net *ip6n, struct ip6_tnl *t) 223 { 224 struct ip6_tnl __rcu **tp; 225 struct ip6_tnl *iter; 226 227 for (tp = ip6_tnl_bucket(ip6n, &t->parms); 228 (iter = rtnl_dereference(*tp)) != NULL; 229 tp = &iter->next) { 230 if (t == iter) { 231 rcu_assign_pointer(*tp, t->next); 232 break; 233 } 234 } 235 } 236 237 static void ip6_dev_free(struct net_device *dev) 238 { 239 struct ip6_tnl *t = netdev_priv(dev); 240 241 dst_cache_destroy(&t->dst_cache); 242 free_percpu(dev->tstats); 243 free_netdev(dev); 244 } 245 246 static int ip6_tnl_create2(struct net_device *dev) 247 { 248 struct ip6_tnl *t = netdev_priv(dev); 249 struct net *net = dev_net(dev); 250 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 251 int err; 252 253 t = netdev_priv(dev); 254 255 err = register_netdevice(dev); 256 if (err < 0) 257 goto out; 258 259 strcpy(t->parms.name, dev->name); 260 dev->rtnl_link_ops = &ip6_link_ops; 261 262 dev_hold(dev); 263 ip6_tnl_link(ip6n, t); 264 return 0; 265 266 out: 267 return err; 268 } 269 270 /** 271 * ip6_tnl_create - create a new tunnel 272 * @p: tunnel parameters 273 * @pt: pointer to new tunnel 274 * 275 * Description: 276 * Create tunnel matching given parameters. 277 * 278 * Return: 279 * created tunnel or error pointer 280 **/ 281 282 static struct ip6_tnl *ip6_tnl_create(struct net *net, struct __ip6_tnl_parm *p) 283 { 284 struct net_device *dev; 285 struct ip6_tnl *t; 286 char name[IFNAMSIZ]; 287 int err = -ENOMEM; 288 289 if (p->name[0]) 290 strlcpy(name, p->name, IFNAMSIZ); 291 else 292 sprintf(name, "ip6tnl%%d"); 293 294 dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN, 295 ip6_tnl_dev_setup); 296 if (!dev) 297 goto failed; 298 299 dev_net_set(dev, net); 300 301 t = netdev_priv(dev); 302 t->parms = *p; 303 t->net = dev_net(dev); 304 err = ip6_tnl_create2(dev); 305 if (err < 0) 306 goto failed_free; 307 308 return t; 309 310 failed_free: 311 ip6_dev_free(dev); 312 failed: 313 return ERR_PTR(err); 314 } 315 316 /** 317 * ip6_tnl_locate - find or create tunnel matching given parameters 318 * @p: tunnel parameters 319 * @create: != 0 if allowed to create new tunnel if no match found 320 * 321 * Description: 322 * ip6_tnl_locate() first tries to locate an existing tunnel 323 * based on @parms. If this is unsuccessful, but @create is set a new 324 * tunnel device is created and registered for use. 325 * 326 * Return: 327 * matching tunnel or error pointer 328 **/ 329 330 static struct ip6_tnl *ip6_tnl_locate(struct net *net, 331 struct __ip6_tnl_parm *p, int create) 332 { 333 const struct in6_addr *remote = &p->raddr; 334 const struct in6_addr *local = &p->laddr; 335 struct ip6_tnl __rcu **tp; 336 struct ip6_tnl *t; 337 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 338 339 for (tp = ip6_tnl_bucket(ip6n, p); 340 (t = rtnl_dereference(*tp)) != NULL; 341 tp = &t->next) { 342 if (ipv6_addr_equal(local, &t->parms.laddr) && 343 ipv6_addr_equal(remote, &t->parms.raddr)) { 344 if (create) 345 return ERR_PTR(-EEXIST); 346 347 return t; 348 } 349 } 350 if (!create) 351 return ERR_PTR(-ENODEV); 352 return ip6_tnl_create(net, p); 353 } 354 355 /** 356 * ip6_tnl_dev_uninit - tunnel device uninitializer 357 * @dev: the device to be destroyed 358 * 359 * Description: 360 * ip6_tnl_dev_uninit() removes tunnel from its list 361 **/ 362 363 static void 364 ip6_tnl_dev_uninit(struct net_device *dev) 365 { 366 struct ip6_tnl *t = netdev_priv(dev); 367 struct net *net = t->net; 368 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 369 370 if (dev == ip6n->fb_tnl_dev) 371 RCU_INIT_POINTER(ip6n->tnls_wc[0], NULL); 372 else 373 ip6_tnl_unlink(ip6n, t); 374 dst_cache_reset(&t->dst_cache); 375 dev_put(dev); 376 } 377 378 /** 379 * parse_tvl_tnl_enc_lim - handle encapsulation limit option 380 * @skb: received socket buffer 381 * 382 * Return: 383 * 0 if none was found, 384 * else index to encapsulation limit 385 **/ 386 387 __u16 ip6_tnl_parse_tlv_enc_lim(struct sk_buff *skb, __u8 *raw) 388 { 389 const struct ipv6hdr *ipv6h = (const struct ipv6hdr *) raw; 390 __u8 nexthdr = ipv6h->nexthdr; 391 __u16 off = sizeof(*ipv6h); 392 393 while (ipv6_ext_hdr(nexthdr) && nexthdr != NEXTHDR_NONE) { 394 __u16 optlen = 0; 395 struct ipv6_opt_hdr *hdr; 396 if (raw + off + sizeof(*hdr) > skb->data && 397 !pskb_may_pull(skb, raw - skb->data + off + sizeof (*hdr))) 398 break; 399 400 hdr = (struct ipv6_opt_hdr *) (raw + off); 401 if (nexthdr == NEXTHDR_FRAGMENT) { 402 struct frag_hdr *frag_hdr = (struct frag_hdr *) hdr; 403 if (frag_hdr->frag_off) 404 break; 405 optlen = 8; 406 } else if (nexthdr == NEXTHDR_AUTH) { 407 optlen = (hdr->hdrlen + 2) << 2; 408 } else { 409 optlen = ipv6_optlen(hdr); 410 } 411 if (nexthdr == NEXTHDR_DEST) { 412 __u16 i = off + 2; 413 while (1) { 414 struct ipv6_tlv_tnl_enc_lim *tel; 415 416 /* No more room for encapsulation limit */ 417 if (i + sizeof (*tel) > off + optlen) 418 break; 419 420 tel = (struct ipv6_tlv_tnl_enc_lim *) &raw[i]; 421 /* return index of option if found and valid */ 422 if (tel->type == IPV6_TLV_TNL_ENCAP_LIMIT && 423 tel->length == 1) 424 return i; 425 /* else jump to next option */ 426 if (tel->type) 427 i += tel->length + 2; 428 else 429 i++; 430 } 431 } 432 nexthdr = hdr->nexthdr; 433 off += optlen; 434 } 435 return 0; 436 } 437 EXPORT_SYMBOL(ip6_tnl_parse_tlv_enc_lim); 438 439 /** 440 * ip6_tnl_err - tunnel error handler 441 * 442 * Description: 443 * ip6_tnl_err() should handle errors in the tunnel according 444 * to the specifications in RFC 2473. 445 **/ 446 447 static int 448 ip6_tnl_err(struct sk_buff *skb, __u8 ipproto, struct inet6_skb_parm *opt, 449 u8 *type, u8 *code, int *msg, __u32 *info, int offset) 450 { 451 const struct ipv6hdr *ipv6h = (const struct ipv6hdr *) skb->data; 452 struct ip6_tnl *t; 453 int rel_msg = 0; 454 u8 rel_type = ICMPV6_DEST_UNREACH; 455 u8 rel_code = ICMPV6_ADDR_UNREACH; 456 u8 tproto; 457 __u32 rel_info = 0; 458 __u16 len; 459 int err = -ENOENT; 460 461 /* If the packet doesn't contain the original IPv6 header we are 462 in trouble since we might need the source address for further 463 processing of the error. */ 464 465 rcu_read_lock(); 466 t = ip6_tnl_lookup(dev_net(skb->dev), &ipv6h->daddr, &ipv6h->saddr); 467 if (!t) 468 goto out; 469 470 tproto = ACCESS_ONCE(t->parms.proto); 471 if (tproto != ipproto && tproto != 0) 472 goto out; 473 474 err = 0; 475 476 switch (*type) { 477 __u32 teli; 478 struct ipv6_tlv_tnl_enc_lim *tel; 479 __u32 mtu; 480 case ICMPV6_DEST_UNREACH: 481 net_dbg_ratelimited("%s: Path to destination invalid or inactive!\n", 482 t->parms.name); 483 rel_msg = 1; 484 break; 485 case ICMPV6_TIME_EXCEED: 486 if ((*code) == ICMPV6_EXC_HOPLIMIT) { 487 net_dbg_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n", 488 t->parms.name); 489 rel_msg = 1; 490 } 491 break; 492 case ICMPV6_PARAMPROB: 493 teli = 0; 494 if ((*code) == ICMPV6_HDR_FIELD) 495 teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data); 496 497 if (teli && teli == *info - 2) { 498 tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli]; 499 if (tel->encap_limit == 0) { 500 net_dbg_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n", 501 t->parms.name); 502 rel_msg = 1; 503 } 504 } else { 505 net_dbg_ratelimited("%s: Recipient unable to parse tunneled packet!\n", 506 t->parms.name); 507 } 508 break; 509 case ICMPV6_PKT_TOOBIG: 510 mtu = *info - offset; 511 if (mtu < IPV6_MIN_MTU) 512 mtu = IPV6_MIN_MTU; 513 t->dev->mtu = mtu; 514 515 len = sizeof(*ipv6h) + ntohs(ipv6h->payload_len); 516 if (len > mtu) { 517 rel_type = ICMPV6_PKT_TOOBIG; 518 rel_code = 0; 519 rel_info = mtu; 520 rel_msg = 1; 521 } 522 break; 523 } 524 525 *type = rel_type; 526 *code = rel_code; 527 *info = rel_info; 528 *msg = rel_msg; 529 530 out: 531 rcu_read_unlock(); 532 return err; 533 } 534 535 static int 536 ip4ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 537 u8 type, u8 code, int offset, __be32 info) 538 { 539 int rel_msg = 0; 540 u8 rel_type = type; 541 u8 rel_code = code; 542 __u32 rel_info = ntohl(info); 543 int err; 544 struct sk_buff *skb2; 545 const struct iphdr *eiph; 546 struct rtable *rt; 547 struct flowi4 fl4; 548 549 err = ip6_tnl_err(skb, IPPROTO_IPIP, opt, &rel_type, &rel_code, 550 &rel_msg, &rel_info, offset); 551 if (err < 0) 552 return err; 553 554 if (rel_msg == 0) 555 return 0; 556 557 switch (rel_type) { 558 case ICMPV6_DEST_UNREACH: 559 if (rel_code != ICMPV6_ADDR_UNREACH) 560 return 0; 561 rel_type = ICMP_DEST_UNREACH; 562 rel_code = ICMP_HOST_UNREACH; 563 break; 564 case ICMPV6_PKT_TOOBIG: 565 if (rel_code != 0) 566 return 0; 567 rel_type = ICMP_DEST_UNREACH; 568 rel_code = ICMP_FRAG_NEEDED; 569 break; 570 case NDISC_REDIRECT: 571 rel_type = ICMP_REDIRECT; 572 rel_code = ICMP_REDIR_HOST; 573 default: 574 return 0; 575 } 576 577 if (!pskb_may_pull(skb, offset + sizeof(struct iphdr))) 578 return 0; 579 580 skb2 = skb_clone(skb, GFP_ATOMIC); 581 if (!skb2) 582 return 0; 583 584 skb_dst_drop(skb2); 585 586 skb_pull(skb2, offset); 587 skb_reset_network_header(skb2); 588 eiph = ip_hdr(skb2); 589 590 /* Try to guess incoming interface */ 591 rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL, 592 eiph->saddr, 0, 593 0, 0, 594 IPPROTO_IPIP, RT_TOS(eiph->tos), 0); 595 if (IS_ERR(rt)) 596 goto out; 597 598 skb2->dev = rt->dst.dev; 599 600 /* route "incoming" packet */ 601 if (rt->rt_flags & RTCF_LOCAL) { 602 ip_rt_put(rt); 603 rt = NULL; 604 rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL, 605 eiph->daddr, eiph->saddr, 606 0, 0, 607 IPPROTO_IPIP, 608 RT_TOS(eiph->tos), 0); 609 if (IS_ERR(rt) || 610 rt->dst.dev->type != ARPHRD_TUNNEL) { 611 if (!IS_ERR(rt)) 612 ip_rt_put(rt); 613 goto out; 614 } 615 skb_dst_set(skb2, &rt->dst); 616 } else { 617 ip_rt_put(rt); 618 if (ip_route_input(skb2, eiph->daddr, eiph->saddr, eiph->tos, 619 skb2->dev) || 620 skb_dst(skb2)->dev->type != ARPHRD_TUNNEL) 621 goto out; 622 } 623 624 /* change mtu on this route */ 625 if (rel_type == ICMP_DEST_UNREACH && rel_code == ICMP_FRAG_NEEDED) { 626 if (rel_info > dst_mtu(skb_dst(skb2))) 627 goto out; 628 629 skb_dst(skb2)->ops->update_pmtu(skb_dst(skb2), NULL, skb2, rel_info); 630 } 631 if (rel_type == ICMP_REDIRECT) 632 skb_dst(skb2)->ops->redirect(skb_dst(skb2), NULL, skb2); 633 634 icmp_send(skb2, rel_type, rel_code, htonl(rel_info)); 635 636 out: 637 kfree_skb(skb2); 638 return 0; 639 } 640 641 static int 642 ip6ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 643 u8 type, u8 code, int offset, __be32 info) 644 { 645 int rel_msg = 0; 646 u8 rel_type = type; 647 u8 rel_code = code; 648 __u32 rel_info = ntohl(info); 649 int err; 650 651 err = ip6_tnl_err(skb, IPPROTO_IPV6, opt, &rel_type, &rel_code, 652 &rel_msg, &rel_info, offset); 653 if (err < 0) 654 return err; 655 656 if (rel_msg && pskb_may_pull(skb, offset + sizeof(struct ipv6hdr))) { 657 struct rt6_info *rt; 658 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC); 659 660 if (!skb2) 661 return 0; 662 663 skb_dst_drop(skb2); 664 skb_pull(skb2, offset); 665 skb_reset_network_header(skb2); 666 667 /* Try to guess incoming interface */ 668 rt = rt6_lookup(dev_net(skb->dev), &ipv6_hdr(skb2)->saddr, 669 NULL, 0, 0); 670 671 if (rt && rt->dst.dev) 672 skb2->dev = rt->dst.dev; 673 674 icmpv6_send(skb2, rel_type, rel_code, rel_info); 675 676 ip6_rt_put(rt); 677 678 kfree_skb(skb2); 679 } 680 681 return 0; 682 } 683 684 static int ip4ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t, 685 const struct ipv6hdr *ipv6h, 686 struct sk_buff *skb) 687 { 688 __u8 dsfield = ipv6_get_dsfield(ipv6h) & ~INET_ECN_MASK; 689 690 if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY) 691 ipv4_change_dsfield(ip_hdr(skb), INET_ECN_MASK, dsfield); 692 693 return IP6_ECN_decapsulate(ipv6h, skb); 694 } 695 696 static int ip6ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t, 697 const struct ipv6hdr *ipv6h, 698 struct sk_buff *skb) 699 { 700 if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY) 701 ipv6_copy_dscp(ipv6_get_dsfield(ipv6h), ipv6_hdr(skb)); 702 703 return IP6_ECN_decapsulate(ipv6h, skb); 704 } 705 706 __u32 ip6_tnl_get_cap(struct ip6_tnl *t, 707 const struct in6_addr *laddr, 708 const struct in6_addr *raddr) 709 { 710 struct __ip6_tnl_parm *p = &t->parms; 711 int ltype = ipv6_addr_type(laddr); 712 int rtype = ipv6_addr_type(raddr); 713 __u32 flags = 0; 714 715 if (ltype == IPV6_ADDR_ANY || rtype == IPV6_ADDR_ANY) { 716 flags = IP6_TNL_F_CAP_PER_PACKET; 717 } else if (ltype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) && 718 rtype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) && 719 !((ltype|rtype) & IPV6_ADDR_LOOPBACK) && 720 (!((ltype|rtype) & IPV6_ADDR_LINKLOCAL) || p->link)) { 721 if (ltype&IPV6_ADDR_UNICAST) 722 flags |= IP6_TNL_F_CAP_XMIT; 723 if (rtype&IPV6_ADDR_UNICAST) 724 flags |= IP6_TNL_F_CAP_RCV; 725 } 726 return flags; 727 } 728 EXPORT_SYMBOL(ip6_tnl_get_cap); 729 730 /* called with rcu_read_lock() */ 731 int ip6_tnl_rcv_ctl(struct ip6_tnl *t, 732 const struct in6_addr *laddr, 733 const struct in6_addr *raddr) 734 { 735 struct __ip6_tnl_parm *p = &t->parms; 736 int ret = 0; 737 struct net *net = t->net; 738 739 if ((p->flags & IP6_TNL_F_CAP_RCV) || 740 ((p->flags & IP6_TNL_F_CAP_PER_PACKET) && 741 (ip6_tnl_get_cap(t, laddr, raddr) & IP6_TNL_F_CAP_RCV))) { 742 struct net_device *ldev = NULL; 743 744 if (p->link) 745 ldev = dev_get_by_index_rcu(net, p->link); 746 747 if ((ipv6_addr_is_multicast(laddr) || 748 likely(ipv6_chk_addr(net, laddr, ldev, 0))) && 749 likely(!ipv6_chk_addr(net, raddr, NULL, 0))) 750 ret = 1; 751 } 752 return ret; 753 } 754 EXPORT_SYMBOL_GPL(ip6_tnl_rcv_ctl); 755 756 /** 757 * ip6_tnl_rcv - decapsulate IPv6 packet and retransmit it locally 758 * @skb: received socket buffer 759 * @protocol: ethernet protocol ID 760 * @dscp_ecn_decapsulate: the function to decapsulate DSCP code and ECN 761 * 762 * Return: 0 763 **/ 764 765 static int ip6_tnl_rcv(struct sk_buff *skb, __u16 protocol, 766 __u8 ipproto, 767 int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t, 768 const struct ipv6hdr *ipv6h, 769 struct sk_buff *skb)) 770 { 771 struct ip6_tnl *t; 772 const struct ipv6hdr *ipv6h = ipv6_hdr(skb); 773 u8 tproto; 774 int err; 775 776 rcu_read_lock(); 777 t = ip6_tnl_lookup(dev_net(skb->dev), &ipv6h->saddr, &ipv6h->daddr); 778 if (t) { 779 struct pcpu_sw_netstats *tstats; 780 781 tproto = ACCESS_ONCE(t->parms.proto); 782 if (tproto != ipproto && tproto != 0) { 783 rcu_read_unlock(); 784 goto discard; 785 } 786 787 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) { 788 rcu_read_unlock(); 789 goto discard; 790 } 791 792 if (!ip6_tnl_rcv_ctl(t, &ipv6h->daddr, &ipv6h->saddr)) { 793 t->dev->stats.rx_dropped++; 794 rcu_read_unlock(); 795 goto discard; 796 } 797 skb->mac_header = skb->network_header; 798 skb_reset_network_header(skb); 799 skb->protocol = htons(protocol); 800 memset(skb->cb, 0, sizeof(struct inet6_skb_parm)); 801 802 __skb_tunnel_rx(skb, t->dev, t->net); 803 804 err = dscp_ecn_decapsulate(t, ipv6h, skb); 805 if (unlikely(err)) { 806 if (log_ecn_error) 807 net_info_ratelimited("non-ECT from %pI6 with dsfield=%#x\n", 808 &ipv6h->saddr, 809 ipv6_get_dsfield(ipv6h)); 810 if (err > 1) { 811 ++t->dev->stats.rx_frame_errors; 812 ++t->dev->stats.rx_errors; 813 rcu_read_unlock(); 814 goto discard; 815 } 816 } 817 818 tstats = this_cpu_ptr(t->dev->tstats); 819 u64_stats_update_begin(&tstats->syncp); 820 tstats->rx_packets++; 821 tstats->rx_bytes += skb->len; 822 u64_stats_update_end(&tstats->syncp); 823 824 netif_rx(skb); 825 826 rcu_read_unlock(); 827 return 0; 828 } 829 rcu_read_unlock(); 830 return 1; 831 832 discard: 833 kfree_skb(skb); 834 return 0; 835 } 836 837 static int ip4ip6_rcv(struct sk_buff *skb) 838 { 839 return ip6_tnl_rcv(skb, ETH_P_IP, IPPROTO_IPIP, 840 ip4ip6_dscp_ecn_decapsulate); 841 } 842 843 static int ip6ip6_rcv(struct sk_buff *skb) 844 { 845 return ip6_tnl_rcv(skb, ETH_P_IPV6, IPPROTO_IPV6, 846 ip6ip6_dscp_ecn_decapsulate); 847 } 848 849 struct ipv6_tel_txoption { 850 struct ipv6_txoptions ops; 851 __u8 dst_opt[8]; 852 }; 853 854 static void init_tel_txopt(struct ipv6_tel_txoption *opt, __u8 encap_limit) 855 { 856 memset(opt, 0, sizeof(struct ipv6_tel_txoption)); 857 858 opt->dst_opt[2] = IPV6_TLV_TNL_ENCAP_LIMIT; 859 opt->dst_opt[3] = 1; 860 opt->dst_opt[4] = encap_limit; 861 opt->dst_opt[5] = IPV6_TLV_PADN; 862 opt->dst_opt[6] = 1; 863 864 opt->ops.dst0opt = (struct ipv6_opt_hdr *) opt->dst_opt; 865 opt->ops.opt_nflen = 8; 866 } 867 868 /** 869 * ip6_tnl_addr_conflict - compare packet addresses to tunnel's own 870 * @t: the outgoing tunnel device 871 * @hdr: IPv6 header from the incoming packet 872 * 873 * Description: 874 * Avoid trivial tunneling loop by checking that tunnel exit-point 875 * doesn't match source of incoming packet. 876 * 877 * Return: 878 * 1 if conflict, 879 * 0 else 880 **/ 881 882 static inline bool 883 ip6_tnl_addr_conflict(const struct ip6_tnl *t, const struct ipv6hdr *hdr) 884 { 885 return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr); 886 } 887 888 int ip6_tnl_xmit_ctl(struct ip6_tnl *t, 889 const struct in6_addr *laddr, 890 const struct in6_addr *raddr) 891 { 892 struct __ip6_tnl_parm *p = &t->parms; 893 int ret = 0; 894 struct net *net = t->net; 895 896 if ((p->flags & IP6_TNL_F_CAP_XMIT) || 897 ((p->flags & IP6_TNL_F_CAP_PER_PACKET) && 898 (ip6_tnl_get_cap(t, laddr, raddr) & IP6_TNL_F_CAP_XMIT))) { 899 struct net_device *ldev = NULL; 900 901 rcu_read_lock(); 902 if (p->link) 903 ldev = dev_get_by_index_rcu(net, p->link); 904 905 if (unlikely(!ipv6_chk_addr(net, laddr, ldev, 0))) 906 pr_warn("%s xmit: Local address not yet configured!\n", 907 p->name); 908 else if (!ipv6_addr_is_multicast(raddr) && 909 unlikely(ipv6_chk_addr(net, raddr, NULL, 0))) 910 pr_warn("%s xmit: Routing loop! Remote address found on this node!\n", 911 p->name); 912 else 913 ret = 1; 914 rcu_read_unlock(); 915 } 916 return ret; 917 } 918 EXPORT_SYMBOL_GPL(ip6_tnl_xmit_ctl); 919 920 /** 921 * ip6_tnl_xmit2 - encapsulate packet and send 922 * @skb: the outgoing socket buffer 923 * @dev: the outgoing tunnel device 924 * @dsfield: dscp code for outer header 925 * @fl: flow of tunneled packet 926 * @encap_limit: encapsulation limit 927 * @pmtu: Path MTU is stored if packet is too big 928 * 929 * Description: 930 * Build new header and do some sanity checks on the packet before sending 931 * it. 932 * 933 * Return: 934 * 0 on success 935 * -1 fail 936 * %-EMSGSIZE message too big. return mtu in this case. 937 **/ 938 939 static int ip6_tnl_xmit2(struct sk_buff *skb, 940 struct net_device *dev, 941 __u8 dsfield, 942 struct flowi6 *fl6, 943 int encap_limit, 944 __u32 *pmtu) 945 { 946 struct ip6_tnl *t = netdev_priv(dev); 947 struct net *net = t->net; 948 struct net_device_stats *stats = &t->dev->stats; 949 struct ipv6hdr *ipv6h = ipv6_hdr(skb); 950 struct ipv6_tel_txoption opt; 951 struct dst_entry *dst = NULL, *ndst = NULL; 952 struct net_device *tdev; 953 int mtu; 954 unsigned int max_headroom = sizeof(struct ipv6hdr); 955 u8 proto; 956 int err = -1; 957 958 /* NBMA tunnel */ 959 if (ipv6_addr_any(&t->parms.raddr)) { 960 struct in6_addr *addr6; 961 struct neighbour *neigh; 962 int addr_type; 963 964 if (!skb_dst(skb)) 965 goto tx_err_link_failure; 966 967 neigh = dst_neigh_lookup(skb_dst(skb), 968 &ipv6_hdr(skb)->daddr); 969 if (!neigh) 970 goto tx_err_link_failure; 971 972 addr6 = (struct in6_addr *)&neigh->primary_key; 973 addr_type = ipv6_addr_type(addr6); 974 975 if (addr_type == IPV6_ADDR_ANY) 976 addr6 = &ipv6_hdr(skb)->daddr; 977 978 memcpy(&fl6->daddr, addr6, sizeof(fl6->daddr)); 979 neigh_release(neigh); 980 } else if (!fl6->flowi6_mark) 981 dst = dst_cache_get(&t->dst_cache); 982 983 if (!ip6_tnl_xmit_ctl(t, &fl6->saddr, &fl6->daddr)) 984 goto tx_err_link_failure; 985 986 if (!dst) { 987 dst = ip6_route_output(net, NULL, fl6); 988 989 if (dst->error) 990 goto tx_err_link_failure; 991 dst = xfrm_lookup(net, dst, flowi6_to_flowi(fl6), NULL, 0); 992 if (IS_ERR(dst)) { 993 err = PTR_ERR(dst); 994 dst = NULL; 995 goto tx_err_link_failure; 996 } 997 ndst = dst; 998 } 999 1000 tdev = dst->dev; 1001 1002 if (tdev == dev) { 1003 stats->collisions++; 1004 net_warn_ratelimited("%s: Local routing loop detected!\n", 1005 t->parms.name); 1006 goto tx_err_dst_release; 1007 } 1008 mtu = dst_mtu(dst) - sizeof(*ipv6h); 1009 if (encap_limit >= 0) { 1010 max_headroom += 8; 1011 mtu -= 8; 1012 } 1013 if (mtu < IPV6_MIN_MTU) 1014 mtu = IPV6_MIN_MTU; 1015 if (skb_dst(skb)) 1016 skb_dst(skb)->ops->update_pmtu(skb_dst(skb), NULL, skb, mtu); 1017 if (skb->len > mtu) { 1018 *pmtu = mtu; 1019 err = -EMSGSIZE; 1020 goto tx_err_dst_release; 1021 } 1022 1023 skb_scrub_packet(skb, !net_eq(t->net, dev_net(dev))); 1024 1025 /* 1026 * Okay, now see if we can stuff it in the buffer as-is. 1027 */ 1028 max_headroom += LL_RESERVED_SPACE(tdev); 1029 1030 if (skb_headroom(skb) < max_headroom || skb_shared(skb) || 1031 (skb_cloned(skb) && !skb_clone_writable(skb, 0))) { 1032 struct sk_buff *new_skb; 1033 1034 new_skb = skb_realloc_headroom(skb, max_headroom); 1035 if (!new_skb) 1036 goto tx_err_dst_release; 1037 1038 if (skb->sk) 1039 skb_set_owner_w(new_skb, skb->sk); 1040 consume_skb(skb); 1041 skb = new_skb; 1042 } 1043 1044 if (!fl6->flowi6_mark && ndst) 1045 dst_cache_set_ip6(&t->dst_cache, ndst, &fl6->saddr); 1046 skb_dst_set(skb, dst); 1047 1048 skb->transport_header = skb->network_header; 1049 1050 proto = fl6->flowi6_proto; 1051 if (encap_limit >= 0) { 1052 init_tel_txopt(&opt, encap_limit); 1053 ipv6_push_nfrag_opts(skb, &opt.ops, &proto, NULL); 1054 } 1055 1056 if (likely(!skb->encapsulation)) { 1057 skb_reset_inner_headers(skb); 1058 skb->encapsulation = 1; 1059 } 1060 1061 skb_push(skb, sizeof(struct ipv6hdr)); 1062 skb_reset_network_header(skb); 1063 ipv6h = ipv6_hdr(skb); 1064 ip6_flow_hdr(ipv6h, INET_ECN_encapsulate(0, dsfield), 1065 ip6_make_flowlabel(net, skb, fl6->flowlabel, true, fl6)); 1066 ipv6h->hop_limit = t->parms.hop_limit; 1067 ipv6h->nexthdr = proto; 1068 ipv6h->saddr = fl6->saddr; 1069 ipv6h->daddr = fl6->daddr; 1070 ip6tunnel_xmit(NULL, skb, dev); 1071 return 0; 1072 tx_err_link_failure: 1073 stats->tx_carrier_errors++; 1074 dst_link_failure(skb); 1075 tx_err_dst_release: 1076 dst_release(dst); 1077 return err; 1078 } 1079 1080 static inline int 1081 ip4ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev) 1082 { 1083 struct ip6_tnl *t = netdev_priv(dev); 1084 const struct iphdr *iph = ip_hdr(skb); 1085 int encap_limit = -1; 1086 struct flowi6 fl6; 1087 __u8 dsfield; 1088 __u32 mtu; 1089 u8 tproto; 1090 int err; 1091 1092 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); 1093 1094 tproto = ACCESS_ONCE(t->parms.proto); 1095 if (tproto != IPPROTO_IPIP && tproto != 0) 1096 return -1; 1097 1098 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1099 encap_limit = t->parms.encap_limit; 1100 1101 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 1102 fl6.flowi6_proto = IPPROTO_IPIP; 1103 1104 dsfield = ipv4_get_dsfield(iph); 1105 1106 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) 1107 fl6.flowlabel |= htonl((__u32)iph->tos << IPV6_TCLASS_SHIFT) 1108 & IPV6_TCLASS_MASK; 1109 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK) 1110 fl6.flowi6_mark = skb->mark; 1111 1112 err = ip6_tnl_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu); 1113 if (err != 0) { 1114 /* XXX: send ICMP error even if DF is not set. */ 1115 if (err == -EMSGSIZE) 1116 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, 1117 htonl(mtu)); 1118 return -1; 1119 } 1120 1121 return 0; 1122 } 1123 1124 static inline int 1125 ip6ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev) 1126 { 1127 struct ip6_tnl *t = netdev_priv(dev); 1128 struct ipv6hdr *ipv6h = ipv6_hdr(skb); 1129 int encap_limit = -1; 1130 __u16 offset; 1131 struct flowi6 fl6; 1132 __u8 dsfield; 1133 __u32 mtu; 1134 u8 tproto; 1135 int err; 1136 1137 tproto = ACCESS_ONCE(t->parms.proto); 1138 if ((tproto != IPPROTO_IPV6 && tproto != 0) || 1139 ip6_tnl_addr_conflict(t, ipv6h)) 1140 return -1; 1141 1142 offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb)); 1143 if (offset > 0) { 1144 struct ipv6_tlv_tnl_enc_lim *tel; 1145 tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset]; 1146 if (tel->encap_limit == 0) { 1147 icmpv6_send(skb, ICMPV6_PARAMPROB, 1148 ICMPV6_HDR_FIELD, offset + 2); 1149 return -1; 1150 } 1151 encap_limit = tel->encap_limit - 1; 1152 } else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1153 encap_limit = t->parms.encap_limit; 1154 1155 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 1156 fl6.flowi6_proto = IPPROTO_IPV6; 1157 1158 dsfield = ipv6_get_dsfield(ipv6h); 1159 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) 1160 fl6.flowlabel |= (*(__be32 *) ipv6h & IPV6_TCLASS_MASK); 1161 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL) 1162 fl6.flowlabel |= ip6_flowlabel(ipv6h); 1163 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK) 1164 fl6.flowi6_mark = skb->mark; 1165 1166 err = ip6_tnl_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu); 1167 if (err != 0) { 1168 if (err == -EMSGSIZE) 1169 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); 1170 return -1; 1171 } 1172 1173 return 0; 1174 } 1175 1176 static netdev_tx_t 1177 ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev) 1178 { 1179 struct ip6_tnl *t = netdev_priv(dev); 1180 struct net_device_stats *stats = &t->dev->stats; 1181 int ret; 1182 1183 switch (skb->protocol) { 1184 case htons(ETH_P_IP): 1185 ret = ip4ip6_tnl_xmit(skb, dev); 1186 break; 1187 case htons(ETH_P_IPV6): 1188 ret = ip6ip6_tnl_xmit(skb, dev); 1189 break; 1190 default: 1191 goto tx_err; 1192 } 1193 1194 if (ret < 0) 1195 goto tx_err; 1196 1197 return NETDEV_TX_OK; 1198 1199 tx_err: 1200 stats->tx_errors++; 1201 stats->tx_dropped++; 1202 kfree_skb(skb); 1203 return NETDEV_TX_OK; 1204 } 1205 1206 static void ip6_tnl_link_config(struct ip6_tnl *t) 1207 { 1208 struct net_device *dev = t->dev; 1209 struct __ip6_tnl_parm *p = &t->parms; 1210 struct flowi6 *fl6 = &t->fl.u.ip6; 1211 1212 memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr)); 1213 memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr)); 1214 1215 /* Set up flowi template */ 1216 fl6->saddr = p->laddr; 1217 fl6->daddr = p->raddr; 1218 fl6->flowi6_oif = p->link; 1219 fl6->flowlabel = 0; 1220 1221 if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS)) 1222 fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo; 1223 if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL)) 1224 fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo; 1225 1226 p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET); 1227 p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr); 1228 1229 if (p->flags&IP6_TNL_F_CAP_XMIT && p->flags&IP6_TNL_F_CAP_RCV) 1230 dev->flags |= IFF_POINTOPOINT; 1231 else 1232 dev->flags &= ~IFF_POINTOPOINT; 1233 1234 if (p->flags & IP6_TNL_F_CAP_XMIT) { 1235 int strict = (ipv6_addr_type(&p->raddr) & 1236 (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL)); 1237 1238 struct rt6_info *rt = rt6_lookup(t->net, 1239 &p->raddr, &p->laddr, 1240 p->link, strict); 1241 1242 if (!rt) 1243 return; 1244 1245 if (rt->dst.dev) { 1246 dev->hard_header_len = rt->dst.dev->hard_header_len + 1247 sizeof(struct ipv6hdr); 1248 1249 dev->mtu = rt->dst.dev->mtu - sizeof(struct ipv6hdr); 1250 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1251 dev->mtu -= 8; 1252 1253 if (dev->mtu < IPV6_MIN_MTU) 1254 dev->mtu = IPV6_MIN_MTU; 1255 } 1256 ip6_rt_put(rt); 1257 } 1258 } 1259 1260 /** 1261 * ip6_tnl_change - update the tunnel parameters 1262 * @t: tunnel to be changed 1263 * @p: tunnel configuration parameters 1264 * 1265 * Description: 1266 * ip6_tnl_change() updates the tunnel parameters 1267 **/ 1268 1269 static int 1270 ip6_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p) 1271 { 1272 t->parms.laddr = p->laddr; 1273 t->parms.raddr = p->raddr; 1274 t->parms.flags = p->flags; 1275 t->parms.hop_limit = p->hop_limit; 1276 t->parms.encap_limit = p->encap_limit; 1277 t->parms.flowinfo = p->flowinfo; 1278 t->parms.link = p->link; 1279 t->parms.proto = p->proto; 1280 dst_cache_reset(&t->dst_cache); 1281 ip6_tnl_link_config(t); 1282 return 0; 1283 } 1284 1285 static int ip6_tnl_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p) 1286 { 1287 struct net *net = t->net; 1288 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1289 int err; 1290 1291 ip6_tnl_unlink(ip6n, t); 1292 synchronize_net(); 1293 err = ip6_tnl_change(t, p); 1294 ip6_tnl_link(ip6n, t); 1295 netdev_state_change(t->dev); 1296 return err; 1297 } 1298 1299 static int ip6_tnl0_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p) 1300 { 1301 /* for default tnl0 device allow to change only the proto */ 1302 t->parms.proto = p->proto; 1303 netdev_state_change(t->dev); 1304 return 0; 1305 } 1306 1307 static void 1308 ip6_tnl_parm_from_user(struct __ip6_tnl_parm *p, const struct ip6_tnl_parm *u) 1309 { 1310 p->laddr = u->laddr; 1311 p->raddr = u->raddr; 1312 p->flags = u->flags; 1313 p->hop_limit = u->hop_limit; 1314 p->encap_limit = u->encap_limit; 1315 p->flowinfo = u->flowinfo; 1316 p->link = u->link; 1317 p->proto = u->proto; 1318 memcpy(p->name, u->name, sizeof(u->name)); 1319 } 1320 1321 static void 1322 ip6_tnl_parm_to_user(struct ip6_tnl_parm *u, const struct __ip6_tnl_parm *p) 1323 { 1324 u->laddr = p->laddr; 1325 u->raddr = p->raddr; 1326 u->flags = p->flags; 1327 u->hop_limit = p->hop_limit; 1328 u->encap_limit = p->encap_limit; 1329 u->flowinfo = p->flowinfo; 1330 u->link = p->link; 1331 u->proto = p->proto; 1332 memcpy(u->name, p->name, sizeof(u->name)); 1333 } 1334 1335 /** 1336 * ip6_tnl_ioctl - configure ipv6 tunnels from userspace 1337 * @dev: virtual device associated with tunnel 1338 * @ifr: parameters passed from userspace 1339 * @cmd: command to be performed 1340 * 1341 * Description: 1342 * ip6_tnl_ioctl() is used for managing IPv6 tunnels 1343 * from userspace. 1344 * 1345 * The possible commands are the following: 1346 * %SIOCGETTUNNEL: get tunnel parameters for device 1347 * %SIOCADDTUNNEL: add tunnel matching given tunnel parameters 1348 * %SIOCCHGTUNNEL: change tunnel parameters to those given 1349 * %SIOCDELTUNNEL: delete tunnel 1350 * 1351 * The fallback device "ip6tnl0", created during module 1352 * initialization, can be used for creating other tunnel devices. 1353 * 1354 * Return: 1355 * 0 on success, 1356 * %-EFAULT if unable to copy data to or from userspace, 1357 * %-EPERM if current process hasn't %CAP_NET_ADMIN set 1358 * %-EINVAL if passed tunnel parameters are invalid, 1359 * %-EEXIST if changing a tunnel's parameters would cause a conflict 1360 * %-ENODEV if attempting to change or delete a nonexisting device 1361 **/ 1362 1363 static int 1364 ip6_tnl_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd) 1365 { 1366 int err = 0; 1367 struct ip6_tnl_parm p; 1368 struct __ip6_tnl_parm p1; 1369 struct ip6_tnl *t = netdev_priv(dev); 1370 struct net *net = t->net; 1371 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1372 1373 switch (cmd) { 1374 case SIOCGETTUNNEL: 1375 if (dev == ip6n->fb_tnl_dev) { 1376 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) { 1377 err = -EFAULT; 1378 break; 1379 } 1380 ip6_tnl_parm_from_user(&p1, &p); 1381 t = ip6_tnl_locate(net, &p1, 0); 1382 if (IS_ERR(t)) 1383 t = netdev_priv(dev); 1384 } else { 1385 memset(&p, 0, sizeof(p)); 1386 } 1387 ip6_tnl_parm_to_user(&p, &t->parms); 1388 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) { 1389 err = -EFAULT; 1390 } 1391 break; 1392 case SIOCADDTUNNEL: 1393 case SIOCCHGTUNNEL: 1394 err = -EPERM; 1395 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 1396 break; 1397 err = -EFAULT; 1398 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 1399 break; 1400 err = -EINVAL; 1401 if (p.proto != IPPROTO_IPV6 && p.proto != IPPROTO_IPIP && 1402 p.proto != 0) 1403 break; 1404 ip6_tnl_parm_from_user(&p1, &p); 1405 t = ip6_tnl_locate(net, &p1, cmd == SIOCADDTUNNEL); 1406 if (cmd == SIOCCHGTUNNEL) { 1407 if (!IS_ERR(t)) { 1408 if (t->dev != dev) { 1409 err = -EEXIST; 1410 break; 1411 } 1412 } else 1413 t = netdev_priv(dev); 1414 if (dev == ip6n->fb_tnl_dev) 1415 err = ip6_tnl0_update(t, &p1); 1416 else 1417 err = ip6_tnl_update(t, &p1); 1418 } 1419 if (!IS_ERR(t)) { 1420 err = 0; 1421 ip6_tnl_parm_to_user(&p, &t->parms); 1422 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) 1423 err = -EFAULT; 1424 1425 } else { 1426 err = PTR_ERR(t); 1427 } 1428 break; 1429 case SIOCDELTUNNEL: 1430 err = -EPERM; 1431 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 1432 break; 1433 1434 if (dev == ip6n->fb_tnl_dev) { 1435 err = -EFAULT; 1436 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 1437 break; 1438 err = -ENOENT; 1439 ip6_tnl_parm_from_user(&p1, &p); 1440 t = ip6_tnl_locate(net, &p1, 0); 1441 if (IS_ERR(t)) 1442 break; 1443 err = -EPERM; 1444 if (t->dev == ip6n->fb_tnl_dev) 1445 break; 1446 dev = t->dev; 1447 } 1448 err = 0; 1449 unregister_netdevice(dev); 1450 break; 1451 default: 1452 err = -EINVAL; 1453 } 1454 return err; 1455 } 1456 1457 /** 1458 * ip6_tnl_change_mtu - change mtu manually for tunnel device 1459 * @dev: virtual device associated with tunnel 1460 * @new_mtu: the new mtu 1461 * 1462 * Return: 1463 * 0 on success, 1464 * %-EINVAL if mtu too small 1465 **/ 1466 1467 static int 1468 ip6_tnl_change_mtu(struct net_device *dev, int new_mtu) 1469 { 1470 struct ip6_tnl *tnl = netdev_priv(dev); 1471 1472 if (tnl->parms.proto == IPPROTO_IPIP) { 1473 if (new_mtu < 68) 1474 return -EINVAL; 1475 } else { 1476 if (new_mtu < IPV6_MIN_MTU) 1477 return -EINVAL; 1478 } 1479 if (new_mtu > 0xFFF8 - dev->hard_header_len) 1480 return -EINVAL; 1481 dev->mtu = new_mtu; 1482 return 0; 1483 } 1484 1485 int ip6_tnl_get_iflink(const struct net_device *dev) 1486 { 1487 struct ip6_tnl *t = netdev_priv(dev); 1488 1489 return t->parms.link; 1490 } 1491 EXPORT_SYMBOL(ip6_tnl_get_iflink); 1492 1493 static const struct net_device_ops ip6_tnl_netdev_ops = { 1494 .ndo_init = ip6_tnl_dev_init, 1495 .ndo_uninit = ip6_tnl_dev_uninit, 1496 .ndo_start_xmit = ip6_tnl_xmit, 1497 .ndo_do_ioctl = ip6_tnl_ioctl, 1498 .ndo_change_mtu = ip6_tnl_change_mtu, 1499 .ndo_get_stats = ip6_get_stats, 1500 .ndo_get_iflink = ip6_tnl_get_iflink, 1501 }; 1502 1503 1504 /** 1505 * ip6_tnl_dev_setup - setup virtual tunnel device 1506 * @dev: virtual device associated with tunnel 1507 * 1508 * Description: 1509 * Initialize function pointers and device parameters 1510 **/ 1511 1512 static void ip6_tnl_dev_setup(struct net_device *dev) 1513 { 1514 struct ip6_tnl *t; 1515 1516 dev->netdev_ops = &ip6_tnl_netdev_ops; 1517 dev->destructor = ip6_dev_free; 1518 1519 dev->type = ARPHRD_TUNNEL6; 1520 dev->hard_header_len = LL_MAX_HEADER + sizeof(struct ipv6hdr); 1521 dev->mtu = ETH_DATA_LEN - sizeof(struct ipv6hdr); 1522 t = netdev_priv(dev); 1523 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1524 dev->mtu -= 8; 1525 dev->flags |= IFF_NOARP; 1526 dev->addr_len = sizeof(struct in6_addr); 1527 netif_keep_dst(dev); 1528 /* This perm addr will be used as interface identifier by IPv6 */ 1529 dev->addr_assign_type = NET_ADDR_RANDOM; 1530 eth_random_addr(dev->perm_addr); 1531 } 1532 1533 1534 /** 1535 * ip6_tnl_dev_init_gen - general initializer for all tunnel devices 1536 * @dev: virtual device associated with tunnel 1537 **/ 1538 1539 static inline int 1540 ip6_tnl_dev_init_gen(struct net_device *dev) 1541 { 1542 struct ip6_tnl *t = netdev_priv(dev); 1543 int ret; 1544 1545 t->dev = dev; 1546 t->net = dev_net(dev); 1547 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats); 1548 if (!dev->tstats) 1549 return -ENOMEM; 1550 1551 ret = dst_cache_init(&t->dst_cache, GFP_KERNEL); 1552 if (ret) { 1553 free_percpu(dev->tstats); 1554 dev->tstats = NULL; 1555 return ret; 1556 } 1557 1558 return 0; 1559 } 1560 1561 /** 1562 * ip6_tnl_dev_init - initializer for all non fallback tunnel devices 1563 * @dev: virtual device associated with tunnel 1564 **/ 1565 1566 static int ip6_tnl_dev_init(struct net_device *dev) 1567 { 1568 struct ip6_tnl *t = netdev_priv(dev); 1569 int err = ip6_tnl_dev_init_gen(dev); 1570 1571 if (err) 1572 return err; 1573 ip6_tnl_link_config(t); 1574 return 0; 1575 } 1576 1577 /** 1578 * ip6_fb_tnl_dev_init - initializer for fallback tunnel device 1579 * @dev: fallback device 1580 * 1581 * Return: 0 1582 **/ 1583 1584 static int __net_init ip6_fb_tnl_dev_init(struct net_device *dev) 1585 { 1586 struct ip6_tnl *t = netdev_priv(dev); 1587 struct net *net = dev_net(dev); 1588 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1589 1590 t->parms.proto = IPPROTO_IPV6; 1591 dev_hold(dev); 1592 1593 rcu_assign_pointer(ip6n->tnls_wc[0], t); 1594 return 0; 1595 } 1596 1597 static int ip6_tnl_validate(struct nlattr *tb[], struct nlattr *data[]) 1598 { 1599 u8 proto; 1600 1601 if (!data || !data[IFLA_IPTUN_PROTO]) 1602 return 0; 1603 1604 proto = nla_get_u8(data[IFLA_IPTUN_PROTO]); 1605 if (proto != IPPROTO_IPV6 && 1606 proto != IPPROTO_IPIP && 1607 proto != 0) 1608 return -EINVAL; 1609 1610 return 0; 1611 } 1612 1613 static void ip6_tnl_netlink_parms(struct nlattr *data[], 1614 struct __ip6_tnl_parm *parms) 1615 { 1616 memset(parms, 0, sizeof(*parms)); 1617 1618 if (!data) 1619 return; 1620 1621 if (data[IFLA_IPTUN_LINK]) 1622 parms->link = nla_get_u32(data[IFLA_IPTUN_LINK]); 1623 1624 if (data[IFLA_IPTUN_LOCAL]) 1625 parms->laddr = nla_get_in6_addr(data[IFLA_IPTUN_LOCAL]); 1626 1627 if (data[IFLA_IPTUN_REMOTE]) 1628 parms->raddr = nla_get_in6_addr(data[IFLA_IPTUN_REMOTE]); 1629 1630 if (data[IFLA_IPTUN_TTL]) 1631 parms->hop_limit = nla_get_u8(data[IFLA_IPTUN_TTL]); 1632 1633 if (data[IFLA_IPTUN_ENCAP_LIMIT]) 1634 parms->encap_limit = nla_get_u8(data[IFLA_IPTUN_ENCAP_LIMIT]); 1635 1636 if (data[IFLA_IPTUN_FLOWINFO]) 1637 parms->flowinfo = nla_get_be32(data[IFLA_IPTUN_FLOWINFO]); 1638 1639 if (data[IFLA_IPTUN_FLAGS]) 1640 parms->flags = nla_get_u32(data[IFLA_IPTUN_FLAGS]); 1641 1642 if (data[IFLA_IPTUN_PROTO]) 1643 parms->proto = nla_get_u8(data[IFLA_IPTUN_PROTO]); 1644 } 1645 1646 static int ip6_tnl_newlink(struct net *src_net, struct net_device *dev, 1647 struct nlattr *tb[], struct nlattr *data[]) 1648 { 1649 struct net *net = dev_net(dev); 1650 struct ip6_tnl *nt, *t; 1651 1652 nt = netdev_priv(dev); 1653 ip6_tnl_netlink_parms(data, &nt->parms); 1654 1655 t = ip6_tnl_locate(net, &nt->parms, 0); 1656 if (!IS_ERR(t)) 1657 return -EEXIST; 1658 1659 return ip6_tnl_create2(dev); 1660 } 1661 1662 static int ip6_tnl_changelink(struct net_device *dev, struct nlattr *tb[], 1663 struct nlattr *data[]) 1664 { 1665 struct ip6_tnl *t = netdev_priv(dev); 1666 struct __ip6_tnl_parm p; 1667 struct net *net = t->net; 1668 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1669 1670 if (dev == ip6n->fb_tnl_dev) 1671 return -EINVAL; 1672 1673 ip6_tnl_netlink_parms(data, &p); 1674 1675 t = ip6_tnl_locate(net, &p, 0); 1676 if (!IS_ERR(t)) { 1677 if (t->dev != dev) 1678 return -EEXIST; 1679 } else 1680 t = netdev_priv(dev); 1681 1682 return ip6_tnl_update(t, &p); 1683 } 1684 1685 static void ip6_tnl_dellink(struct net_device *dev, struct list_head *head) 1686 { 1687 struct net *net = dev_net(dev); 1688 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1689 1690 if (dev != ip6n->fb_tnl_dev) 1691 unregister_netdevice_queue(dev, head); 1692 } 1693 1694 static size_t ip6_tnl_get_size(const struct net_device *dev) 1695 { 1696 return 1697 /* IFLA_IPTUN_LINK */ 1698 nla_total_size(4) + 1699 /* IFLA_IPTUN_LOCAL */ 1700 nla_total_size(sizeof(struct in6_addr)) + 1701 /* IFLA_IPTUN_REMOTE */ 1702 nla_total_size(sizeof(struct in6_addr)) + 1703 /* IFLA_IPTUN_TTL */ 1704 nla_total_size(1) + 1705 /* IFLA_IPTUN_ENCAP_LIMIT */ 1706 nla_total_size(1) + 1707 /* IFLA_IPTUN_FLOWINFO */ 1708 nla_total_size(4) + 1709 /* IFLA_IPTUN_FLAGS */ 1710 nla_total_size(4) + 1711 /* IFLA_IPTUN_PROTO */ 1712 nla_total_size(1) + 1713 0; 1714 } 1715 1716 static int ip6_tnl_fill_info(struct sk_buff *skb, const struct net_device *dev) 1717 { 1718 struct ip6_tnl *tunnel = netdev_priv(dev); 1719 struct __ip6_tnl_parm *parm = &tunnel->parms; 1720 1721 if (nla_put_u32(skb, IFLA_IPTUN_LINK, parm->link) || 1722 nla_put_in6_addr(skb, IFLA_IPTUN_LOCAL, &parm->laddr) || 1723 nla_put_in6_addr(skb, IFLA_IPTUN_REMOTE, &parm->raddr) || 1724 nla_put_u8(skb, IFLA_IPTUN_TTL, parm->hop_limit) || 1725 nla_put_u8(skb, IFLA_IPTUN_ENCAP_LIMIT, parm->encap_limit) || 1726 nla_put_be32(skb, IFLA_IPTUN_FLOWINFO, parm->flowinfo) || 1727 nla_put_u32(skb, IFLA_IPTUN_FLAGS, parm->flags) || 1728 nla_put_u8(skb, IFLA_IPTUN_PROTO, parm->proto)) 1729 goto nla_put_failure; 1730 return 0; 1731 1732 nla_put_failure: 1733 return -EMSGSIZE; 1734 } 1735 1736 struct net *ip6_tnl_get_link_net(const struct net_device *dev) 1737 { 1738 struct ip6_tnl *tunnel = netdev_priv(dev); 1739 1740 return tunnel->net; 1741 } 1742 EXPORT_SYMBOL(ip6_tnl_get_link_net); 1743 1744 static const struct nla_policy ip6_tnl_policy[IFLA_IPTUN_MAX + 1] = { 1745 [IFLA_IPTUN_LINK] = { .type = NLA_U32 }, 1746 [IFLA_IPTUN_LOCAL] = { .len = sizeof(struct in6_addr) }, 1747 [IFLA_IPTUN_REMOTE] = { .len = sizeof(struct in6_addr) }, 1748 [IFLA_IPTUN_TTL] = { .type = NLA_U8 }, 1749 [IFLA_IPTUN_ENCAP_LIMIT] = { .type = NLA_U8 }, 1750 [IFLA_IPTUN_FLOWINFO] = { .type = NLA_U32 }, 1751 [IFLA_IPTUN_FLAGS] = { .type = NLA_U32 }, 1752 [IFLA_IPTUN_PROTO] = { .type = NLA_U8 }, 1753 }; 1754 1755 static struct rtnl_link_ops ip6_link_ops __read_mostly = { 1756 .kind = "ip6tnl", 1757 .maxtype = IFLA_IPTUN_MAX, 1758 .policy = ip6_tnl_policy, 1759 .priv_size = sizeof(struct ip6_tnl), 1760 .setup = ip6_tnl_dev_setup, 1761 .validate = ip6_tnl_validate, 1762 .newlink = ip6_tnl_newlink, 1763 .changelink = ip6_tnl_changelink, 1764 .dellink = ip6_tnl_dellink, 1765 .get_size = ip6_tnl_get_size, 1766 .fill_info = ip6_tnl_fill_info, 1767 .get_link_net = ip6_tnl_get_link_net, 1768 }; 1769 1770 static struct xfrm6_tunnel ip4ip6_handler __read_mostly = { 1771 .handler = ip4ip6_rcv, 1772 .err_handler = ip4ip6_err, 1773 .priority = 1, 1774 }; 1775 1776 static struct xfrm6_tunnel ip6ip6_handler __read_mostly = { 1777 .handler = ip6ip6_rcv, 1778 .err_handler = ip6ip6_err, 1779 .priority = 1, 1780 }; 1781 1782 static void __net_exit ip6_tnl_destroy_tunnels(struct net *net) 1783 { 1784 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1785 struct net_device *dev, *aux; 1786 int h; 1787 struct ip6_tnl *t; 1788 LIST_HEAD(list); 1789 1790 for_each_netdev_safe(net, dev, aux) 1791 if (dev->rtnl_link_ops == &ip6_link_ops) 1792 unregister_netdevice_queue(dev, &list); 1793 1794 for (h = 0; h < HASH_SIZE; h++) { 1795 t = rtnl_dereference(ip6n->tnls_r_l[h]); 1796 while (t) { 1797 /* If dev is in the same netns, it has already 1798 * been added to the list by the previous loop. 1799 */ 1800 if (!net_eq(dev_net(t->dev), net)) 1801 unregister_netdevice_queue(t->dev, &list); 1802 t = rtnl_dereference(t->next); 1803 } 1804 } 1805 1806 unregister_netdevice_many(&list); 1807 } 1808 1809 static int __net_init ip6_tnl_init_net(struct net *net) 1810 { 1811 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1812 struct ip6_tnl *t = NULL; 1813 int err; 1814 1815 ip6n->tnls[0] = ip6n->tnls_wc; 1816 ip6n->tnls[1] = ip6n->tnls_r_l; 1817 1818 err = -ENOMEM; 1819 ip6n->fb_tnl_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6tnl0", 1820 NET_NAME_UNKNOWN, ip6_tnl_dev_setup); 1821 1822 if (!ip6n->fb_tnl_dev) 1823 goto err_alloc_dev; 1824 dev_net_set(ip6n->fb_tnl_dev, net); 1825 ip6n->fb_tnl_dev->rtnl_link_ops = &ip6_link_ops; 1826 /* FB netdevice is special: we have one, and only one per netns. 1827 * Allowing to move it to another netns is clearly unsafe. 1828 */ 1829 ip6n->fb_tnl_dev->features |= NETIF_F_NETNS_LOCAL; 1830 1831 err = ip6_fb_tnl_dev_init(ip6n->fb_tnl_dev); 1832 if (err < 0) 1833 goto err_register; 1834 1835 err = register_netdev(ip6n->fb_tnl_dev); 1836 if (err < 0) 1837 goto err_register; 1838 1839 t = netdev_priv(ip6n->fb_tnl_dev); 1840 1841 strcpy(t->parms.name, ip6n->fb_tnl_dev->name); 1842 return 0; 1843 1844 err_register: 1845 ip6_dev_free(ip6n->fb_tnl_dev); 1846 err_alloc_dev: 1847 return err; 1848 } 1849 1850 static void __net_exit ip6_tnl_exit_net(struct net *net) 1851 { 1852 rtnl_lock(); 1853 ip6_tnl_destroy_tunnels(net); 1854 rtnl_unlock(); 1855 } 1856 1857 static struct pernet_operations ip6_tnl_net_ops = { 1858 .init = ip6_tnl_init_net, 1859 .exit = ip6_tnl_exit_net, 1860 .id = &ip6_tnl_net_id, 1861 .size = sizeof(struct ip6_tnl_net), 1862 }; 1863 1864 /** 1865 * ip6_tunnel_init - register protocol and reserve needed resources 1866 * 1867 * Return: 0 on success 1868 **/ 1869 1870 static int __init ip6_tunnel_init(void) 1871 { 1872 int err; 1873 1874 err = register_pernet_device(&ip6_tnl_net_ops); 1875 if (err < 0) 1876 goto out_pernet; 1877 1878 err = xfrm6_tunnel_register(&ip4ip6_handler, AF_INET); 1879 if (err < 0) { 1880 pr_err("%s: can't register ip4ip6\n", __func__); 1881 goto out_ip4ip6; 1882 } 1883 1884 err = xfrm6_tunnel_register(&ip6ip6_handler, AF_INET6); 1885 if (err < 0) { 1886 pr_err("%s: can't register ip6ip6\n", __func__); 1887 goto out_ip6ip6; 1888 } 1889 err = rtnl_link_register(&ip6_link_ops); 1890 if (err < 0) 1891 goto rtnl_link_failed; 1892 1893 return 0; 1894 1895 rtnl_link_failed: 1896 xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6); 1897 out_ip6ip6: 1898 xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET); 1899 out_ip4ip6: 1900 unregister_pernet_device(&ip6_tnl_net_ops); 1901 out_pernet: 1902 return err; 1903 } 1904 1905 /** 1906 * ip6_tunnel_cleanup - free resources and unregister protocol 1907 **/ 1908 1909 static void __exit ip6_tunnel_cleanup(void) 1910 { 1911 rtnl_link_unregister(&ip6_link_ops); 1912 if (xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET)) 1913 pr_info("%s: can't deregister ip4ip6\n", __func__); 1914 1915 if (xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6)) 1916 pr_info("%s: can't deregister ip6ip6\n", __func__); 1917 1918 unregister_pernet_device(&ip6_tnl_net_ops); 1919 } 1920 1921 module_init(ip6_tunnel_init); 1922 module_exit(ip6_tunnel_cleanup); 1923