net/ipv6/ip6_tunnel.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *      IPv6 tunneling device
   4  *      Linux INET6 implementation
   5  *
   6  *      Authors:
   7  *      Ville Nuorvala          <vnuorval@tcs.hut.fi>
   8  *      Yasuyuki Kozakai        <kozakai@linux-ipv6.org>
   9  *
  10  *      Based on:
  11  *      linux/net/ipv6/sit.c and linux/net/ipv4/ipip.c
  12  *
  13  *      RFC 2473
  14  */
  15
  16 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  17
  18 #include <linux/module.h>
  19 #include <linux/capability.h>
  20 #include <linux/errno.h>
  21 #include <linux/types.h>
  22 #include <linux/sockios.h>
  23 #include <linux/icmp.h>
  24 #include <linux/if.h>
  25 #include <linux/in.h>
  26 #include <linux/ip.h>
  27 #include <linux/net.h>
  28 #include <linux/in6.h>
  29 #include <linux/netdevice.h>
  30 #include <linux/if_arp.h>
  31 #include <linux/icmpv6.h>
  32 #include <linux/init.h>
  33 #include <linux/route.h>
  34 #include <linux/rtnetlink.h>
  35 #include <linux/netfilter_ipv6.h>
  36 #include <linux/slab.h>
  37 #include <linux/hash.h>
  38 #include <linux/etherdevice.h>
  39
  40 #include <linux/uaccess.h>
  41 #include <linux/atomic.h>
  42
  43 #include <net/icmp.h>
  44 #include <net/ip.h>
  45 #include <net/ip_tunnels.h>
  46 #include <net/ipv6.h>
  47 #include <net/ip6_route.h>
  48 #include <net/addrconf.h>
  49 #include <net/ip6_tunnel.h>
  50 #include <net/xfrm.h>
  51 #include <net/dsfield.h>
  52 #include <net/inet_ecn.h>
  53 #include <net/net_namespace.h>
  54 #include <net/netns/generic.h>
  55 #include <net/dst_metadata.h>
  56
  57 MODULE_AUTHOR("Ville Nuorvala");
  58 MODULE_DESCRIPTION("IPv6 tunneling device");
  59 MODULE_LICENSE("GPL");
  60 MODULE_ALIAS_RTNL_LINK("ip6tnl");
  61 MODULE_ALIAS_NETDEV("ip6tnl0");
  62
  63 #define IP6_TUNNEL_HASH_SIZE_SHIFT  5
  64 #define IP6_TUNNEL_HASH_SIZE (1 << IP6_TUNNEL_HASH_SIZE_SHIFT)
  65
  66 static bool log_ecn_error = true;
  67 module_param(log_ecn_error, bool, 0644);
  68 MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");
  69
  70 static u32 HASH(const struct in6_addr *addr1, const struct in6_addr *addr2)
  71 {
  72         u32 hash = ipv6_addr_hash(addr1) ^ ipv6_addr_hash(addr2);
  73
  74         return hash_32(hash, IP6_TUNNEL_HASH_SIZE_SHIFT);
  75 }
  76
  77 static int ip6_tnl_dev_init(struct net_device *dev);
  78 static void ip6_tnl_dev_setup(struct net_device *dev);
  79 static struct rtnl_link_ops ip6_link_ops __read_mostly;
  80
  81 static unsigned int ip6_tnl_net_id __read_mostly;
  82 struct ip6_tnl_net {
  83         /* the IPv6 tunnel fallback device */
  84         struct net_device *fb_tnl_dev;
  85         /* lists for storing tunnels in use */
  86         struct ip6_tnl __rcu *tnls_r_l[IP6_TUNNEL_HASH_SIZE];
  87         struct ip6_tnl __rcu *tnls_wc[1];
  88         struct ip6_tnl __rcu **tnls[2];
  89         struct ip6_tnl __rcu *collect_md_tun;
  90 };
  91
  92 static inline int ip6_tnl_mpls_supported(void)
  93 {
  94         return IS_ENABLED(CONFIG_MPLS);
  95 }
  96
  97 #define for_each_ip6_tunnel_rcu(start) \
  98         for (t = rcu_dereference(start); t; t = rcu_dereference(t->next))
  99
 100 /**
 101  * ip6_tnl_lookup - fetch tunnel matching the end-point addresses
 102  *   @net: network namespace
 103  *   @link: ifindex of underlying interface
 104  *   @remote: the address of the tunnel exit-point
 105  *   @local: the address of the tunnel entry-point
 106  *
 107  * Return:
 108  *   tunnel matching given end-points if found,
 109  *   else fallback tunnel if its device is up,
 110  *   else %NULL
 111  **/
 112
 113 static struct ip6_tnl *
 114 ip6_tnl_lookup(struct net *net, int link,
 115                const struct in6_addr *remote, const struct in6_addr *local)
 116 {
 117         unsigned int hash = HASH(remote, local);
 118         struct ip6_tnl *t, *cand = NULL;
 119         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
 120         struct in6_addr any;
 121
 122         for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
 123                 if (!ipv6_addr_equal(local, &t->parms.laddr) ||
 124                     !ipv6_addr_equal(remote, &t->parms.raddr) ||
 125                     !(t->dev->flags & IFF_UP))
 126                         continue;
 127
 128                 if (link == t->parms.link)
 129                         return t;
 130                 else
 131                         cand = t;
 132         }
 133
 134         memset(&any, 0, sizeof(any));
 135         hash = HASH(&any, local);
 136         for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
 137                 if (!ipv6_addr_equal(local, &t->parms.laddr) ||
 138                     !ipv6_addr_any(&t->parms.raddr) ||
 139                     !(t->dev->flags & IFF_UP))
 140                         continue;
 141
 142                 if (link == t->parms.link)
 143                         return t;
 144                 else if (!cand)
 145                         cand = t;
 146         }
 147
 148         hash = HASH(remote, &any);
 149         for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
 150                 if (!ipv6_addr_equal(remote, &t->parms.raddr) ||
 151                     !ipv6_addr_any(&t->parms.laddr) ||
 152                     !(t->dev->flags & IFF_UP))
 153                         continue;
 154
 155                 if (link == t->parms.link)
 156                         return t;
 157                 else if (!cand)
 158                         cand = t;
 159         }
 160
 161         if (cand)
 162                 return cand;
 163
 164         t = rcu_dereference(ip6n->collect_md_tun);
 165         if (t && t->dev->flags & IFF_UP)
 166                 return t;
 167
 168         t = rcu_dereference(ip6n->tnls_wc[0]);
 169         if (t && (t->dev->flags & IFF_UP))
 170                 return t;
 171
 172         return NULL;
 173 }
 174
 175 /**
 176  * ip6_tnl_bucket - get head of list matching given tunnel parameters
 177  *   @ip6n: the private data for ip6_vti in the netns
 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  *   @ip6n: the private data for ip6_vti in the netns
 205  *   @t: tunnel to be added
 206  **/
 207
 208 static void
 209 ip6_tnl_link(struct ip6_tnl_net *ip6n, struct ip6_tnl *t)
 210 {
 211         struct ip6_tnl __rcu **tp = ip6_tnl_bucket(ip6n, &t->parms);
 212
 213         if (t->parms.collect_md)
 214                 rcu_assign_pointer(ip6n->collect_md_tun, t);
 215         rcu_assign_pointer(t->next , rtnl_dereference(*tp));
 216         rcu_assign_pointer(*tp, t);
 217 }
 218
 219 /**
 220  * ip6_tnl_unlink - remove tunnel from hash table
 221  *   @ip6n: the private data for ip6_vti in the netns
 222  *   @t: tunnel to be removed
 223  **/
 224
 225 static void
 226 ip6_tnl_unlink(struct ip6_tnl_net *ip6n, struct ip6_tnl *t)
 227 {
 228         struct ip6_tnl __rcu **tp;
 229         struct ip6_tnl *iter;
 230
 231         if (t->parms.collect_md)
 232                 rcu_assign_pointer(ip6n->collect_md_tun, NULL);
 233
 234         for (tp = ip6_tnl_bucket(ip6n, &t->parms);
 235              (iter = rtnl_dereference(*tp)) != NULL;
 236              tp = &iter->next) {
 237                 if (t == iter) {
 238                         rcu_assign_pointer(*tp, t->next);
 239                         break;
 240                 }
 241         }
 242 }
 243
 244 static void ip6_dev_free(struct net_device *dev)
 245 {
 246         struct ip6_tnl *t = netdev_priv(dev);
 247
 248         gro_cells_destroy(&t->gro_cells);
 249         dst_cache_destroy(&t->dst_cache);
 250         free_percpu(dev->tstats);
 251 }
 252
 253 static int ip6_tnl_create2(struct net_device *dev)
 254 {
 255         struct ip6_tnl *t = netdev_priv(dev);
 256         struct net *net = dev_net(dev);
 257         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
 258         int err;
 259
 260         dev->rtnl_link_ops = &ip6_link_ops;
 261         err = register_netdevice(dev);
 262         if (err < 0)
 263                 goto out;
 264
 265         strcpy(t->parms.name, dev->name);
 266
 267         ip6_tnl_link(ip6n, t);
 268         return 0;
 269
 270 out:
 271         return err;
 272 }
 273
 274 /**
 275  * ip6_tnl_create - create a new tunnel
 276  *   @net: network namespace
 277  *   @p: tunnel parameters
 278  *
 279  * Description:
 280  *   Create tunnel matching given parameters.
 281  *
 282  * Return:
 283  *   created tunnel or error pointer
 284  **/
 285
 286 static struct ip6_tnl *ip6_tnl_create(struct net *net, struct __ip6_tnl_parm *p)
 287 {
 288         struct net_device *dev;
 289         struct ip6_tnl *t;
 290         char name[IFNAMSIZ];
 291         int err = -E2BIG;
 292
 293         if (p->name[0]) {
 294                 if (!dev_valid_name(p->name))
 295                         goto failed;
 296                 strlcpy(name, p->name, IFNAMSIZ);
 297         } else {
 298                 sprintf(name, "ip6tnl%%d");
 299         }
 300         err = -ENOMEM;
 301         dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN,
 302                            ip6_tnl_dev_setup);
 303         if (!dev)
 304                 goto failed;
 305
 306         dev_net_set(dev, net);
 307
 308         t = netdev_priv(dev);
 309         t->parms = *p;
 310         t->net = dev_net(dev);
 311         err = ip6_tnl_create2(dev);
 312         if (err < 0)
 313                 goto failed_free;
 314
 315         return t;
 316
 317 failed_free:
 318         free_netdev(dev);
 319 failed:
 320         return ERR_PTR(err);
 321 }
 322
 323 /**
 324  * ip6_tnl_locate - find or create tunnel matching given parameters
 325  *   @net: network namespace
 326  *   @p: tunnel parameters
 327  *   @create: != 0 if allowed to create new tunnel if no match found
 328  *
 329  * Description:
 330  *   ip6_tnl_locate() first tries to locate an existing tunnel
 331  *   based on @parms. If this is unsuccessful, but @create is set a new
 332  *   tunnel device is created and registered for use.
 333  *
 334  * Return:
 335  *   matching tunnel or error pointer
 336  **/
 337
 338 static struct ip6_tnl *ip6_tnl_locate(struct net *net,
 339                 struct __ip6_tnl_parm *p, int create)
 340 {
 341         const struct in6_addr *remote = &p->raddr;
 342         const struct in6_addr *local = &p->laddr;
 343         struct ip6_tnl __rcu **tp;
 344         struct ip6_tnl *t;
 345         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
 346
 347         for (tp = ip6_tnl_bucket(ip6n, p);
 348              (t = rtnl_dereference(*tp)) != NULL;
 349              tp = &t->next) {
 350                 if (ipv6_addr_equal(local, &t->parms.laddr) &&
 351                     ipv6_addr_equal(remote, &t->parms.raddr) &&
 352                     p->link == t->parms.link) {
 353                         if (create)
 354                                 return ERR_PTR(-EEXIST);
 355
 356                         return t;
 357                 }
 358         }
 359         if (!create)
 360                 return ERR_PTR(-ENODEV);
 361         return ip6_tnl_create(net, p);
 362 }
 363
 364 /**
 365  * ip6_tnl_dev_uninit - tunnel device uninitializer
 366  *   @dev: the device to be destroyed
 367  *
 368  * Description:
 369  *   ip6_tnl_dev_uninit() removes tunnel from its list
 370  **/
 371
 372 static void
 373 ip6_tnl_dev_uninit(struct net_device *dev)
 374 {
 375         struct ip6_tnl *t = netdev_priv(dev);
 376         struct net *net = t->net;
 377         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
 378
 379         if (dev == ip6n->fb_tnl_dev)
 380                 RCU_INIT_POINTER(ip6n->tnls_wc[0], NULL);
 381         else
 382                 ip6_tnl_unlink(ip6n, t);
 383         dst_cache_reset(&t->dst_cache);
 384         dev_put_track(dev, &t->dev_tracker);
 385 }
 386
 387 /**
 388  * ip6_tnl_parse_tlv_enc_lim - handle encapsulation limit option
 389  *   @skb: received socket buffer
 390  *   @raw: the ICMPv6 error message data
 391  *
 392  * Return:
 393  *   0 if none was found,
 394  *   else index to encapsulation limit
 395  **/
 396
 397 __u16 ip6_tnl_parse_tlv_enc_lim(struct sk_buff *skb, __u8 *raw)
 398 {
 399         const struct ipv6hdr *ipv6h = (const struct ipv6hdr *)raw;
 400         unsigned int nhoff = raw - skb->data;
 401         unsigned int off = nhoff + sizeof(*ipv6h);
 402         u8 next, nexthdr = ipv6h->nexthdr;
 403
 404         while (ipv6_ext_hdr(nexthdr) && nexthdr != NEXTHDR_NONE) {
 405                 struct ipv6_opt_hdr *hdr;
 406                 u16 optlen;
 407
 408                 if (!pskb_may_pull(skb, off + sizeof(*hdr)))
 409                         break;
 410
 411                 hdr = (struct ipv6_opt_hdr *)(skb->data + off);
 412                 if (nexthdr == NEXTHDR_FRAGMENT) {
 413                         struct frag_hdr *frag_hdr = (struct frag_hdr *) hdr;
 414                         if (frag_hdr->frag_off)
 415                                 break;
 416                         optlen = 8;
 417                 } else if (nexthdr == NEXTHDR_AUTH) {
 418                         optlen = ipv6_authlen(hdr);
 419                 } else {
 420                         optlen = ipv6_optlen(hdr);
 421                 }
 422                 /* cache hdr->nexthdr, since pskb_may_pull() might
 423                  * invalidate hdr
 424                  */
 425                 next = hdr->nexthdr;
 426                 if (nexthdr == NEXTHDR_DEST) {
 427                         u16 i = 2;
 428
 429                         /* Remember : hdr is no longer valid at this point. */
 430                         if (!pskb_may_pull(skb, off + optlen))
 431                                 break;
 432
 433                         while (1) {
 434                                 struct ipv6_tlv_tnl_enc_lim *tel;
 435
 436                                 /* No more room for encapsulation limit */
 437                                 if (i + sizeof(*tel) > optlen)
 438                                         break;
 439
 440                                 tel = (struct ipv6_tlv_tnl_enc_lim *)(skb->data + off + i);
 441                                 /* return index of option if found and valid */
 442                                 if (tel->type == IPV6_TLV_TNL_ENCAP_LIMIT &&
 443                                     tel->length == 1)
 444                                         return i + off - nhoff;
 445                                 /* else jump to next option */
 446                                 if (tel->type)
 447                                         i += tel->length + 2;
 448                                 else
 449                                         i++;
 450                         }
 451                 }
 452                 nexthdr = next;
 453                 off += optlen;
 454         }
 455         return 0;
 456 }
 457 EXPORT_SYMBOL(ip6_tnl_parse_tlv_enc_lim);
 458
 459 /* ip6_tnl_err() should handle errors in the tunnel according to the
 460  * specifications in RFC 2473.
 461  */
 462 static int
 463 ip6_tnl_err(struct sk_buff *skb, __u8 ipproto, struct inet6_skb_parm *opt,
 464             u8 *type, u8 *code, int *msg, __u32 *info, int offset)
 465 {
 466         const struct ipv6hdr *ipv6h = (const struct ipv6hdr *)skb->data;
 467         struct net *net = dev_net(skb->dev);
 468         u8 rel_type = ICMPV6_DEST_UNREACH;
 469         u8 rel_code = ICMPV6_ADDR_UNREACH;
 470         __u32 rel_info = 0;
 471         struct ip6_tnl *t;
 472         int err = -ENOENT;
 473         int rel_msg = 0;
 474         u8 tproto;
 475         __u16 len;
 476
 477         /* If the packet doesn't contain the original IPv6 header we are
 478            in trouble since we might need the source address for further
 479            processing of the error. */
 480
 481         rcu_read_lock();
 482         t = ip6_tnl_lookup(dev_net(skb->dev), skb->dev->ifindex, &ipv6h->daddr, &ipv6h->saddr);
 483         if (!t)
 484                 goto out;
 485
 486         tproto = READ_ONCE(t->parms.proto);
 487         if (tproto != ipproto && tproto != 0)
 488                 goto out;
 489
 490         err = 0;
 491
 492         switch (*type) {
 493         case ICMPV6_DEST_UNREACH:
 494                 net_dbg_ratelimited("%s: Path to destination invalid or inactive!\n",
 495                                     t->parms.name);
 496                 rel_msg = 1;
 497                 break;
 498         case ICMPV6_TIME_EXCEED:
 499                 if ((*code) == ICMPV6_EXC_HOPLIMIT) {
 500                         net_dbg_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n",
 501                                             t->parms.name);
 502                         rel_msg = 1;
 503                 }
 504                 break;
 505         case ICMPV6_PARAMPROB: {
 506                 struct ipv6_tlv_tnl_enc_lim *tel;
 507                 __u32 teli;
 508
 509                 teli = 0;
 510                 if ((*code) == ICMPV6_HDR_FIELD)
 511                         teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data);
 512
 513                 if (teli && teli == *info - 2) {
 514                         tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli];
 515                         if (tel->encap_limit == 0) {
 516                                 net_dbg_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n",
 517                                                     t->parms.name);
 518                                 rel_msg = 1;
 519                         }
 520                 } else {
 521                         net_dbg_ratelimited("%s: Recipient unable to parse tunneled packet!\n",
 522                                             t->parms.name);
 523                 }
 524                 break;
 525         }
 526         case ICMPV6_PKT_TOOBIG: {
 527                 __u32 mtu;
 528
 529                 ip6_update_pmtu(skb, net, htonl(*info), 0, 0,
 530                                 sock_net_uid(net, NULL));
 531                 mtu = *info - offset;
 532                 if (mtu < IPV6_MIN_MTU)
 533                         mtu = IPV6_MIN_MTU;
 534                 len = sizeof(*ipv6h) + ntohs(ipv6h->payload_len);
 535                 if (len > mtu) {
 536                         rel_type = ICMPV6_PKT_TOOBIG;
 537                         rel_code = 0;
 538                         rel_info = mtu;
 539                         rel_msg = 1;
 540                 }
 541                 break;
 542         }
 543         case NDISC_REDIRECT:
 544                 ip6_redirect(skb, net, skb->dev->ifindex, 0,
 545                              sock_net_uid(net, NULL));
 546                 break;
 547         }
 548
 549         *type = rel_type;
 550         *code = rel_code;
 551         *info = rel_info;
 552         *msg = rel_msg;
 553
 554 out:
 555         rcu_read_unlock();
 556         return err;
 557 }
 558
 559 static int
 560 ip4ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 561            u8 type, u8 code, int offset, __be32 info)
 562 {
 563         __u32 rel_info = ntohl(info);
 564         const struct iphdr *eiph;
 565         struct sk_buff *skb2;
 566         int err, rel_msg = 0;
 567         u8 rel_type = type;
 568         u8 rel_code = code;
 569         struct rtable *rt;
 570         struct flowi4 fl4;
 571
 572         err = ip6_tnl_err(skb, IPPROTO_IPIP, opt, &rel_type, &rel_code,
 573                           &rel_msg, &rel_info, offset);
 574         if (err < 0)
 575                 return err;
 576
 577         if (rel_msg == 0)
 578                 return 0;
 579
 580         switch (rel_type) {
 581         case ICMPV6_DEST_UNREACH:
 582                 if (rel_code != ICMPV6_ADDR_UNREACH)
 583                         return 0;
 584                 rel_type = ICMP_DEST_UNREACH;
 585                 rel_code = ICMP_HOST_UNREACH;
 586                 break;
 587         case ICMPV6_PKT_TOOBIG:
 588                 if (rel_code != 0)
 589                         return 0;
 590                 rel_type = ICMP_DEST_UNREACH;
 591                 rel_code = ICMP_FRAG_NEEDED;
 592                 break;
 593         default:
 594                 return 0;
 595         }
 596
 597         if (!pskb_may_pull(skb, offset + sizeof(struct iphdr)))
 598                 return 0;
 599
 600         skb2 = skb_clone(skb, GFP_ATOMIC);
 601         if (!skb2)
 602                 return 0;
 603
 604         skb_dst_drop(skb2);
 605
 606         skb_pull(skb2, offset);
 607         skb_reset_network_header(skb2);
 608         eiph = ip_hdr(skb2);
 609
 610         /* Try to guess incoming interface */
 611         rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL, eiph->saddr,
 612                                    0, 0, 0, IPPROTO_IPIP, RT_TOS(eiph->tos), 0);
 613         if (IS_ERR(rt))
 614                 goto out;
 615
 616         skb2->dev = rt->dst.dev;
 617         ip_rt_put(rt);
 618
 619         /* route "incoming" packet */
 620         if (rt->rt_flags & RTCF_LOCAL) {
 621                 rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL,
 622                                            eiph->daddr, eiph->saddr, 0, 0,
 623                                            IPPROTO_IPIP, RT_TOS(eiph->tos), 0);
 624                 if (IS_ERR(rt) || rt->dst.dev->type != ARPHRD_TUNNEL6) {
 625                         if (!IS_ERR(rt))
 626                                 ip_rt_put(rt);
 627                         goto out;
 628                 }
 629                 skb_dst_set(skb2, &rt->dst);
 630         } else {
 631                 if (ip_route_input(skb2, eiph->daddr, eiph->saddr, eiph->tos,
 632                                    skb2->dev) ||
 633                     skb_dst(skb2)->dev->type != ARPHRD_TUNNEL6)
 634                         goto out;
 635         }
 636
 637         /* change mtu on this route */
 638         if (rel_type == ICMP_DEST_UNREACH && rel_code == ICMP_FRAG_NEEDED) {
 639                 if (rel_info > dst_mtu(skb_dst(skb2)))
 640                         goto out;
 641
 642                 skb_dst_update_pmtu_no_confirm(skb2, rel_info);
 643         }
 644
 645         icmp_send(skb2, rel_type, rel_code, htonl(rel_info));
 646
 647 out:
 648         kfree_skb(skb2);
 649         return 0;
 650 }
 651
 652 static int
 653 ip6ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 654            u8 type, u8 code, int offset, __be32 info)
 655 {
 656         __u32 rel_info = ntohl(info);
 657         int err, rel_msg = 0;
 658         u8 rel_type = type;
 659         u8 rel_code = code;
 660
 661         err = ip6_tnl_err(skb, IPPROTO_IPV6, opt, &rel_type, &rel_code,
 662                           &rel_msg, &rel_info, offset);
 663         if (err < 0)
 664                 return err;
 665
 666         if (rel_msg && pskb_may_pull(skb, offset + sizeof(struct ipv6hdr))) {
 667                 struct rt6_info *rt;
 668                 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
 669
 670                 if (!skb2)
 671                         return 0;
 672
 673                 skb_dst_drop(skb2);
 674                 skb_pull(skb2, offset);
 675                 skb_reset_network_header(skb2);
 676
 677                 /* Try to guess incoming interface */
 678                 rt = rt6_lookup(dev_net(skb->dev), &ipv6_hdr(skb2)->saddr,
 679                                 NULL, 0, skb2, 0);
 680
 681                 if (rt && rt->dst.dev)
 682                         skb2->dev = rt->dst.dev;
 683
 684                 icmpv6_send(skb2, rel_type, rel_code, rel_info);
 685
 686                 ip6_rt_put(rt);
 687
 688                 kfree_skb(skb2);
 689         }
 690
 691         return 0;
 692 }
 693
 694 static int
 695 mplsip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 696             u8 type, u8 code, int offset, __be32 info)
 697 {
 698         __u32 rel_info = ntohl(info);
 699         int err, rel_msg = 0;
 700         u8 rel_type = type;
 701         u8 rel_code = code;
 702
 703         err = ip6_tnl_err(skb, IPPROTO_MPLS, opt, &rel_type, &rel_code,
 704                           &rel_msg, &rel_info, offset);
 705         return err;
 706 }
 707
 708 static int ip4ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t,
 709                                        const struct ipv6hdr *ipv6h,
 710                                        struct sk_buff *skb)
 711 {
 712         __u8 dsfield = ipv6_get_dsfield(ipv6h) & ~INET_ECN_MASK;
 713
 714         if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY)
 715                 ipv4_change_dsfield(ip_hdr(skb), INET_ECN_MASK, dsfield);
 716
 717         return IP6_ECN_decapsulate(ipv6h, skb);
 718 }
 719
 720 static int ip6ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t,
 721                                        const struct ipv6hdr *ipv6h,
 722                                        struct sk_buff *skb)
 723 {
 724         if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY)
 725                 ipv6_copy_dscp(ipv6_get_dsfield(ipv6h), ipv6_hdr(skb));
 726
 727         return IP6_ECN_decapsulate(ipv6h, skb);
 728 }
 729
 730 static inline int mplsip6_dscp_ecn_decapsulate(const struct ip6_tnl *t,
 731                                                const struct ipv6hdr *ipv6h,
 732                                                struct sk_buff *skb)
 733 {
 734         /* ECN is not supported in AF_MPLS */
 735         return 0;
 736 }
 737
 738 __u32 ip6_tnl_get_cap(struct ip6_tnl *t,
 739                              const struct in6_addr *laddr,
 740                              const struct in6_addr *raddr)
 741 {
 742         struct __ip6_tnl_parm *p = &t->parms;
 743         int ltype = ipv6_addr_type(laddr);
 744         int rtype = ipv6_addr_type(raddr);
 745         __u32 flags = 0;
 746
 747         if (ltype == IPV6_ADDR_ANY || rtype == IPV6_ADDR_ANY) {
 748                 flags = IP6_TNL_F_CAP_PER_PACKET;
 749         } else if (ltype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) &&
 750                    rtype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) &&
 751                    !((ltype|rtype) & IPV6_ADDR_LOOPBACK) &&
 752                    (!((ltype|rtype) & IPV6_ADDR_LINKLOCAL) || p->link)) {
 753                 if (ltype&IPV6_ADDR_UNICAST)
 754                         flags |= IP6_TNL_F_CAP_XMIT;
 755                 if (rtype&IPV6_ADDR_UNICAST)
 756                         flags |= IP6_TNL_F_CAP_RCV;
 757         }
 758         return flags;
 759 }
 760 EXPORT_SYMBOL(ip6_tnl_get_cap);
 761
 762 /* called with rcu_read_lock() */
 763 int ip6_tnl_rcv_ctl(struct ip6_tnl *t,
 764                                   const struct in6_addr *laddr,
 765                                   const struct in6_addr *raddr)
 766 {
 767         struct __ip6_tnl_parm *p = &t->parms;
 768         int ret = 0;
 769         struct net *net = t->net;
 770
 771         if ((p->flags & IP6_TNL_F_CAP_RCV) ||
 772             ((p->flags & IP6_TNL_F_CAP_PER_PACKET) &&
 773              (ip6_tnl_get_cap(t, laddr, raddr) & IP6_TNL_F_CAP_RCV))) {
 774                 struct net_device *ldev = NULL;
 775
 776                 if (p->link)
 777                         ldev = dev_get_by_index_rcu(net, p->link);
 778
 779                 if ((ipv6_addr_is_multicast(laddr) ||
 780                      likely(ipv6_chk_addr_and_flags(net, laddr, ldev, false,
 781                                                     0, IFA_F_TENTATIVE))) &&
 782                     ((p->flags & IP6_TNL_F_ALLOW_LOCAL_REMOTE) ||
 783                      likely(!ipv6_chk_addr_and_flags(net, raddr, ldev, true,
 784                                                      0, IFA_F_TENTATIVE))))
 785                         ret = 1;
 786         }
 787         return ret;
 788 }
 789 EXPORT_SYMBOL_GPL(ip6_tnl_rcv_ctl);
 790
 791 static int __ip6_tnl_rcv(struct ip6_tnl *tunnel, struct sk_buff *skb,
 792                          const struct tnl_ptk_info *tpi,
 793                          struct metadata_dst *tun_dst,
 794                          int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t,
 795                                                 const struct ipv6hdr *ipv6h,
 796                                                 struct sk_buff *skb),
 797                          bool log_ecn_err)
 798 {
 799         struct pcpu_sw_netstats *tstats;
 800         const struct ipv6hdr *ipv6h = ipv6_hdr(skb);
 801         int err;
 802
 803         if ((!(tpi->flags & TUNNEL_CSUM) &&
 804              (tunnel->parms.i_flags & TUNNEL_CSUM)) ||
 805             ((tpi->flags & TUNNEL_CSUM) &&
 806              !(tunnel->parms.i_flags & TUNNEL_CSUM))) {
 807                 tunnel->dev->stats.rx_crc_errors++;
 808                 tunnel->dev->stats.rx_errors++;
 809                 goto drop;
 810         }
 811
 812         if (tunnel->parms.i_flags & TUNNEL_SEQ) {
 813                 if (!(tpi->flags & TUNNEL_SEQ) ||
 814                     (tunnel->i_seqno &&
 815                      (s32)(ntohl(tpi->seq) - tunnel->i_seqno) < 0)) {
 816                         tunnel->dev->stats.rx_fifo_errors++;
 817                         tunnel->dev->stats.rx_errors++;
 818                         goto drop;
 819                 }
 820                 tunnel->i_seqno = ntohl(tpi->seq) + 1;
 821         }
 822
 823         skb->protocol = tpi->proto;
 824
 825         /* Warning: All skb pointers will be invalidated! */
 826         if (tunnel->dev->type == ARPHRD_ETHER) {
 827                 if (!pskb_may_pull(skb, ETH_HLEN)) {
 828                         tunnel->dev->stats.rx_length_errors++;
 829                         tunnel->dev->stats.rx_errors++;
 830                         goto drop;
 831                 }
 832
 833                 ipv6h = ipv6_hdr(skb);
 834                 skb->protocol = eth_type_trans(skb, tunnel->dev);
 835                 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);
 836         } else {
 837                 skb->dev = tunnel->dev;
 838                 skb_reset_mac_header(skb);
 839         }
 840
 841         skb_reset_network_header(skb);
 842         memset(skb->cb, 0, sizeof(struct inet6_skb_parm));
 843
 844         __skb_tunnel_rx(skb, tunnel->dev, tunnel->net);
 845
 846         err = dscp_ecn_decapsulate(tunnel, ipv6h, skb);
 847         if (unlikely(err)) {
 848                 if (log_ecn_err)
 849                         net_info_ratelimited("non-ECT from %pI6 with DS=%#x\n",
 850                                              &ipv6h->saddr,
 851                                              ipv6_get_dsfield(ipv6h));
 852                 if (err > 1) {
 853                         ++tunnel->dev->stats.rx_frame_errors;
 854                         ++tunnel->dev->stats.rx_errors;
 855                         goto drop;
 856                 }
 857         }
 858
 859         tstats = this_cpu_ptr(tunnel->dev->tstats);
 860         u64_stats_update_begin(&tstats->syncp);
 861         tstats->rx_packets++;
 862         tstats->rx_bytes += skb->len;
 863         u64_stats_update_end(&tstats->syncp);
 864
 865         skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(tunnel->dev)));
 866
 867         if (tun_dst)
 868                 skb_dst_set(skb, (struct dst_entry *)tun_dst);
 869
 870         gro_cells_receive(&tunnel->gro_cells, skb);
 871         return 0;
 872
 873 drop:
 874         if (tun_dst)
 875                 dst_release((struct dst_entry *)tun_dst);
 876         kfree_skb(skb);
 877         return 0;
 878 }
 879
 880 int ip6_tnl_rcv(struct ip6_tnl *t, struct sk_buff *skb,
 881                 const struct tnl_ptk_info *tpi,
 882                 struct metadata_dst *tun_dst,
 883                 bool log_ecn_err)
 884 {
 885         int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t,
 886                                     const struct ipv6hdr *ipv6h,
 887                                     struct sk_buff *skb);
 888
 889         dscp_ecn_decapsulate = ip6ip6_dscp_ecn_decapsulate;
 890         if (tpi->proto == htons(ETH_P_IP))
 891                 dscp_ecn_decapsulate = ip4ip6_dscp_ecn_decapsulate;
 892
 893         return __ip6_tnl_rcv(t, skb, tpi, tun_dst, dscp_ecn_decapsulate,
 894                              log_ecn_err);
 895 }
 896 EXPORT_SYMBOL(ip6_tnl_rcv);
 897
 898 static const struct tnl_ptk_info tpi_v6 = {
 899         /* no tunnel info required for ipxip6. */
 900         .proto = htons(ETH_P_IPV6),
 901 };
 902
 903 static const struct tnl_ptk_info tpi_v4 = {
 904         /* no tunnel info required for ipxip6. */
 905         .proto = htons(ETH_P_IP),
 906 };
 907
 908 static const struct tnl_ptk_info tpi_mpls = {
 909         /* no tunnel info required for mplsip6. */
 910         .proto = htons(ETH_P_MPLS_UC),
 911 };
 912
 913 static int ipxip6_rcv(struct sk_buff *skb, u8 ipproto,
 914                       const struct tnl_ptk_info *tpi,
 915                       int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t,
 916                                                   const struct ipv6hdr *ipv6h,
 917                                                   struct sk_buff *skb))
 918 {
 919         struct ip6_tnl *t;
 920         const struct ipv6hdr *ipv6h = ipv6_hdr(skb);
 921         struct metadata_dst *tun_dst = NULL;
 922         int ret = -1;
 923
 924         rcu_read_lock();
 925         t = ip6_tnl_lookup(dev_net(skb->dev), skb->dev->ifindex, &ipv6h->saddr, &ipv6h->daddr);
 926
 927         if (t) {
 928                 u8 tproto = READ_ONCE(t->parms.proto);
 929
 930                 if (tproto != ipproto && tproto != 0)
 931                         goto drop;
 932                 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
 933                         goto drop;
 934                 ipv6h = ipv6_hdr(skb);
 935                 if (!ip6_tnl_rcv_ctl(t, &ipv6h->daddr, &ipv6h->saddr))
 936                         goto drop;
 937                 if (iptunnel_pull_header(skb, 0, tpi->proto, false))
 938                         goto drop;
 939                 if (t->parms.collect_md) {
 940                         tun_dst = ipv6_tun_rx_dst(skb, 0, 0, 0);
 941                         if (!tun_dst)
 942                                 goto drop;
 943                 }
 944                 ret = __ip6_tnl_rcv(t, skb, tpi, tun_dst, dscp_ecn_decapsulate,
 945                                     log_ecn_error);
 946         }
 947
 948         rcu_read_unlock();
 949
 950         return ret;
 951
 952 drop:
 953         rcu_read_unlock();
 954         kfree_skb(skb);
 955         return 0;
 956 }
 957
 958 static int ip4ip6_rcv(struct sk_buff *skb)
 959 {
 960         return ipxip6_rcv(skb, IPPROTO_IPIP, &tpi_v4,
 961                           ip4ip6_dscp_ecn_decapsulate);
 962 }
 963
 964 static int ip6ip6_rcv(struct sk_buff *skb)
 965 {
 966         return ipxip6_rcv(skb, IPPROTO_IPV6, &tpi_v6,
 967                           ip6ip6_dscp_ecn_decapsulate);
 968 }
 969
 970 static int mplsip6_rcv(struct sk_buff *skb)
 971 {
 972         return ipxip6_rcv(skb, IPPROTO_MPLS, &tpi_mpls,
 973                           mplsip6_dscp_ecn_decapsulate);
 974 }
 975
 976 struct ipv6_tel_txoption {
 977         struct ipv6_txoptions ops;
 978         __u8 dst_opt[8];
 979 };
 980
 981 static void init_tel_txopt(struct ipv6_tel_txoption *opt, __u8 encap_limit)
 982 {
 983         memset(opt, 0, sizeof(struct ipv6_tel_txoption));
 984
 985         opt->dst_opt[2] = IPV6_TLV_TNL_ENCAP_LIMIT;
 986         opt->dst_opt[3] = 1;
 987         opt->dst_opt[4] = encap_limit;
 988         opt->dst_opt[5] = IPV6_TLV_PADN;
 989         opt->dst_opt[6] = 1;
 990
 991         opt->ops.dst1opt = (struct ipv6_opt_hdr *) opt->dst_opt;
 992         opt->ops.opt_nflen = 8;
 993 }
 994
 995 /**
 996  * ip6_tnl_addr_conflict - compare packet addresses to tunnel's own
 997  *   @t: the outgoing tunnel device
 998  *   @hdr: IPv6 header from the incoming packet
 999  *
1000  * Description:
1001  *   Avoid trivial tunneling loop by checking that tunnel exit-point
1002  *   doesn't match source of incoming packet.
1003  *
1004  * Return:
1005  *   1 if conflict,
1006  *   0 else
1007  **/
1008
1009 static inline bool
1010 ip6_tnl_addr_conflict(const struct ip6_tnl *t, const struct ipv6hdr *hdr)
1011 {
1012         return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr);
1013 }
1014
1015 int ip6_tnl_xmit_ctl(struct ip6_tnl *t,
1016                      const struct in6_addr *laddr,
1017                      const struct in6_addr *raddr)
1018 {
1019         struct __ip6_tnl_parm *p = &t->parms;
1020         int ret = 0;
1021         struct net *net = t->net;
1022
1023         if (t->parms.collect_md)
1024                 return 1;
1025
1026         if ((p->flags & IP6_TNL_F_CAP_XMIT) ||
1027             ((p->flags & IP6_TNL_F_CAP_PER_PACKET) &&
1028              (ip6_tnl_get_cap(t, laddr, raddr) & IP6_TNL_F_CAP_XMIT))) {
1029                 struct net_device *ldev = NULL;
1030
1031                 rcu_read_lock();
1032                 if (p->link)
1033                         ldev = dev_get_by_index_rcu(net, p->link);
1034
1035                 if (unlikely(!ipv6_chk_addr_and_flags(net, laddr, ldev, false,
1036                                                       0, IFA_F_TENTATIVE)))
1037                         pr_warn_ratelimited("%s xmit: Local address not yet configured!\n",
1038                                             p->name);
1039                 else if (!(p->flags & IP6_TNL_F_ALLOW_LOCAL_REMOTE) &&
1040                          !ipv6_addr_is_multicast(raddr) &&
1041                          unlikely(ipv6_chk_addr_and_flags(net, raddr, ldev,
1042                                                           true, 0, IFA_F_TENTATIVE)))
1043                         pr_warn_ratelimited("%s xmit: Routing loop! Remote address found on this node!\n",
1044                                             p->name);
1045                 else
1046                         ret = 1;
1047                 rcu_read_unlock();
1048         }
1049         return ret;
1050 }
1051 EXPORT_SYMBOL_GPL(ip6_tnl_xmit_ctl);
1052
1053 /**
1054  * ip6_tnl_xmit - encapsulate packet and send
1055  *   @skb: the outgoing socket buffer
1056  *   @dev: the outgoing tunnel device
1057  *   @dsfield: dscp code for outer header
1058  *   @fl6: flow of tunneled packet
1059  *   @encap_limit: encapsulation limit
1060  *   @pmtu: Path MTU is stored if packet is too big
1061  *   @proto: next header value
1062  *
1063  * Description:
1064  *   Build new header and do some sanity checks on the packet before sending
1065  *   it.
1066  *
1067  * Return:
1068  *   0 on success
1069  *   -1 fail
1070  *   %-EMSGSIZE message too big. return mtu in this case.
1071  **/
1072
1073 int ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev, __u8 dsfield,
1074                  struct flowi6 *fl6, int encap_limit, __u32 *pmtu,
1075                  __u8 proto)
1076 {
1077         struct ip6_tnl *t = netdev_priv(dev);
1078         struct net *net = t->net;
1079         struct net_device_stats *stats = &t->dev->stats;
1080         struct ipv6hdr *ipv6h;
1081         struct ipv6_tel_txoption opt;
1082         struct dst_entry *dst = NULL, *ndst = NULL;
1083         struct net_device *tdev;
1084         int mtu;
1085         unsigned int eth_hlen = t->dev->type == ARPHRD_ETHER ? ETH_HLEN : 0;
1086         unsigned int psh_hlen = sizeof(struct ipv6hdr) + t->encap_hlen;
1087         unsigned int max_headroom = psh_hlen;
1088         bool use_cache = false;
1089         u8 hop_limit;
1090         int err = -1;
1091
1092         if (t->parms.collect_md) {
1093                 hop_limit = skb_tunnel_info(skb)->key.ttl;
1094                 goto route_lookup;
1095         } else {
1096                 hop_limit = t->parms.hop_limit;
1097         }
1098
1099         /* NBMA tunnel */
1100         if (ipv6_addr_any(&t->parms.raddr)) {
1101                 if (skb->protocol == htons(ETH_P_IPV6)) {
1102                         struct in6_addr *addr6;
1103                         struct neighbour *neigh;
1104                         int addr_type;
1105
1106                         if (!skb_dst(skb))
1107                                 goto tx_err_link_failure;
1108
1109                         neigh = dst_neigh_lookup(skb_dst(skb),
1110                                                  &ipv6_hdr(skb)->daddr);
1111                         if (!neigh)
1112                                 goto tx_err_link_failure;
1113
1114                         addr6 = (struct in6_addr *)&neigh->primary_key;
1115                         addr_type = ipv6_addr_type(addr6);
1116
1117                         if (addr_type == IPV6_ADDR_ANY)
1118                                 addr6 = &ipv6_hdr(skb)->daddr;
1119
1120                         memcpy(&fl6->daddr, addr6, sizeof(fl6->daddr));
1121                         neigh_release(neigh);
1122                 } else if (skb->protocol == htons(ETH_P_IP)) {
1123                         const struct rtable *rt = skb_rtable(skb);
1124
1125                         if (!rt)
1126                                 goto tx_err_link_failure;
1127
1128                         if (rt->rt_gw_family == AF_INET6)
1129                                 memcpy(&fl6->daddr, &rt->rt_gw6, sizeof(fl6->daddr));
1130                 }
1131         } else if (t->parms.proto != 0 && !(t->parms.flags &
1132                                             (IP6_TNL_F_USE_ORIG_TCLASS |
1133                                              IP6_TNL_F_USE_ORIG_FWMARK))) {
1134                 /* enable the cache only if neither the outer protocol nor the
1135                  * routing decision depends on the current inner header value
1136                  */
1137                 use_cache = true;
1138         }
1139
1140         if (use_cache)
1141                 dst = dst_cache_get(&t->dst_cache);
1142
1143         if (!ip6_tnl_xmit_ctl(t, &fl6->saddr, &fl6->daddr))
1144                 goto tx_err_link_failure;
1145
1146         if (!dst) {
1147 route_lookup:
1148                 /* add dsfield to flowlabel for route lookup */
1149                 fl6->flowlabel = ip6_make_flowinfo(dsfield, fl6->flowlabel);
1150
1151                 dst = ip6_route_output(net, NULL, fl6);
1152
1153                 if (dst->error)
1154                         goto tx_err_link_failure;
1155                 dst = xfrm_lookup(net, dst, flowi6_to_flowi(fl6), NULL, 0);
1156                 if (IS_ERR(dst)) {
1157                         err = PTR_ERR(dst);
1158                         dst = NULL;
1159                         goto tx_err_link_failure;
1160                 }
1161                 if (t->parms.collect_md && ipv6_addr_any(&fl6->saddr) &&
1162                     ipv6_dev_get_saddr(net, ip6_dst_idev(dst)->dev,
1163                                        &fl6->daddr, 0, &fl6->saddr))
1164                         goto tx_err_link_failure;
1165                 ndst = dst;
1166         }
1167
1168         tdev = dst->dev;
1169
1170         if (tdev == dev) {
1171                 stats->collisions++;
1172                 net_warn_ratelimited("%s: Local routing loop detected!\n",
1173                                      t->parms.name);
1174                 goto tx_err_dst_release;
1175         }
1176         mtu = dst_mtu(dst) - eth_hlen - psh_hlen - t->tun_hlen;
1177         if (encap_limit >= 0) {
1178                 max_headroom += 8;
1179                 mtu -= 8;
1180         }
1181         mtu = max(mtu, skb->protocol == htons(ETH_P_IPV6) ?
1182                        IPV6_MIN_MTU : IPV4_MIN_MTU);
1183
1184         skb_dst_update_pmtu_no_confirm(skb, mtu);
1185         if (skb->len - t->tun_hlen - eth_hlen > mtu && !skb_is_gso(skb)) {
1186                 *pmtu = mtu;
1187                 err = -EMSGSIZE;
1188                 goto tx_err_dst_release;
1189         }
1190
1191         if (t->err_count > 0) {
1192                 if (time_before(jiffies,
1193                                 t->err_time + IP6TUNNEL_ERR_TIMEO)) {
1194                         t->err_count--;
1195
1196                         dst_link_failure(skb);
1197                 } else {
1198                         t->err_count = 0;
1199                 }
1200         }
1201
1202         skb_scrub_packet(skb, !net_eq(t->net, dev_net(dev)));
1203
1204         /*
1205          * Okay, now see if we can stuff it in the buffer as-is.
1206          */
1207         max_headroom += LL_RESERVED_SPACE(tdev);
1208
1209         if (skb_headroom(skb) < max_headroom || skb_shared(skb) ||
1210             (skb_cloned(skb) && !skb_clone_writable(skb, 0))) {
1211                 struct sk_buff *new_skb;
1212
1213                 new_skb = skb_realloc_headroom(skb, max_headroom);
1214                 if (!new_skb)
1215                         goto tx_err_dst_release;
1216
1217                 if (skb->sk)
1218                         skb_set_owner_w(new_skb, skb->sk);
1219                 consume_skb(skb);
1220                 skb = new_skb;
1221         }
1222
1223         if (t->parms.collect_md) {
1224                 if (t->encap.type != TUNNEL_ENCAP_NONE)
1225                         goto tx_err_dst_release;
1226         } else {
1227                 if (use_cache && ndst)
1228                         dst_cache_set_ip6(&t->dst_cache, ndst, &fl6->saddr);
1229         }
1230         skb_dst_set(skb, dst);
1231
1232         if (hop_limit == 0) {
1233                 if (skb->protocol == htons(ETH_P_IP))
1234                         hop_limit = ip_hdr(skb)->ttl;
1235                 else if (skb->protocol == htons(ETH_P_IPV6))
1236                         hop_limit = ipv6_hdr(skb)->hop_limit;
1237                 else
1238                         hop_limit = ip6_dst_hoplimit(dst);
1239         }
1240
1241         /* Calculate max headroom for all the headers and adjust
1242          * needed_headroom if necessary.
1243          */
1244         max_headroom = LL_RESERVED_SPACE(dst->dev) + sizeof(struct ipv6hdr)
1245                         + dst->header_len + t->hlen;
1246         if (max_headroom > dev->needed_headroom)
1247                 dev->needed_headroom = max_headroom;
1248
1249         err = ip6_tnl_encap(skb, t, &proto, fl6);
1250         if (err)
1251                 return err;
1252
1253         if (encap_limit >= 0) {
1254                 init_tel_txopt(&opt, encap_limit);
1255                 ipv6_push_frag_opts(skb, &opt.ops, &proto);
1256         }
1257
1258         skb_push(skb, sizeof(struct ipv6hdr));
1259         skb_reset_network_header(skb);
1260         ipv6h = ipv6_hdr(skb);
1261         ip6_flow_hdr(ipv6h, dsfield,
1262                      ip6_make_flowlabel(net, skb, fl6->flowlabel, true, fl6));
1263         ipv6h->hop_limit = hop_limit;
1264         ipv6h->nexthdr = proto;
1265         ipv6h->saddr = fl6->saddr;
1266         ipv6h->daddr = fl6->daddr;
1267         ip6tunnel_xmit(NULL, skb, dev);
1268         return 0;
1269 tx_err_link_failure:
1270         stats->tx_carrier_errors++;
1271         dst_link_failure(skb);
1272 tx_err_dst_release:
1273         dst_release(dst);
1274         return err;
1275 }
1276 EXPORT_SYMBOL(ip6_tnl_xmit);
1277
1278 static inline int
1279 ipxip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev,
1280                 u8 protocol)
1281 {
1282         struct ip6_tnl *t = netdev_priv(dev);
1283         struct ipv6hdr *ipv6h;
1284         const struct iphdr  *iph;
1285         int encap_limit = -1;
1286         __u16 offset;
1287         struct flowi6 fl6;
1288         __u8 dsfield, orig_dsfield;
1289         __u32 mtu;
1290         u8 tproto;
1291         int err;
1292
1293         tproto = READ_ONCE(t->parms.proto);
1294         if (tproto != protocol && tproto != 0)
1295                 return -1;
1296
1297         if (t->parms.collect_md) {
1298                 struct ip_tunnel_info *tun_info;
1299                 const struct ip_tunnel_key *key;
1300
1301                 tun_info = skb_tunnel_info(skb);
1302                 if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) ||
1303                              ip_tunnel_info_af(tun_info) != AF_INET6))
1304                         return -1;
1305                 key = &tun_info->key;
1306                 memset(&fl6, 0, sizeof(fl6));
1307                 fl6.flowi6_proto = protocol;
1308                 fl6.saddr = key->u.ipv6.src;
1309                 fl6.daddr = key->u.ipv6.dst;
1310                 fl6.flowlabel = key->label;
1311                 dsfield =  key->tos;
1312                 switch (protocol) {
1313                 case IPPROTO_IPIP:
1314                         iph = ip_hdr(skb);
1315                         orig_dsfield = ipv4_get_dsfield(iph);
1316                         break;
1317                 case IPPROTO_IPV6:
1318                         ipv6h = ipv6_hdr(skb);
1319                         orig_dsfield = ipv6_get_dsfield(ipv6h);
1320                         break;
1321                 default:
1322                         orig_dsfield = dsfield;
1323                         break;
1324                 }
1325         } else {
1326                 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1327                         encap_limit = t->parms.encap_limit;
1328                 if (protocol == IPPROTO_IPV6) {
1329                         offset = ip6_tnl_parse_tlv_enc_lim(skb,
1330                                                 skb_network_header(skb));
1331                         /* ip6_tnl_parse_tlv_enc_lim() might have
1332                          * reallocated skb->head
1333                          */
1334                         if (offset > 0) {
1335                                 struct ipv6_tlv_tnl_enc_lim *tel;
1336
1337                                 tel = (void *)&skb_network_header(skb)[offset];
1338                                 if (tel->encap_limit == 0) {
1339                                         icmpv6_ndo_send(skb, ICMPV6_PARAMPROB,
1340                                                         ICMPV6_HDR_FIELD, offset + 2);
1341                                         return -1;
1342                                 }
1343                                 encap_limit = tel->encap_limit - 1;
1344                         }
1345                 }
1346
1347                 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
1348                 fl6.flowi6_proto = protocol;
1349
1350                 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
1351                         fl6.flowi6_mark = skb->mark;
1352                 else
1353                         fl6.flowi6_mark = t->parms.fwmark;
1354                 switch (protocol) {
1355                 case IPPROTO_IPIP:
1356                         iph = ip_hdr(skb);
1357                         orig_dsfield = ipv4_get_dsfield(iph);
1358                         if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
1359                                 dsfield = orig_dsfield;
1360                         else
1361                                 dsfield = ip6_tclass(t->parms.flowinfo);
1362                         break;
1363                 case IPPROTO_IPV6:
1364                         ipv6h = ipv6_hdr(skb);
1365                         orig_dsfield = ipv6_get_dsfield(ipv6h);
1366                         if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
1367                                 dsfield = orig_dsfield;
1368                         else
1369                                 dsfield = ip6_tclass(t->parms.flowinfo);
1370                         if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL)
1371                                 fl6.flowlabel |= ip6_flowlabel(ipv6h);
1372                         break;
1373                 default:
1374                         orig_dsfield = dsfield = ip6_tclass(t->parms.flowinfo);
1375                         break;
1376                 }
1377         }
1378
1379         fl6.flowi6_uid = sock_net_uid(dev_net(dev), NULL);
1380         dsfield = INET_ECN_encapsulate(dsfield, orig_dsfield);
1381
1382         if (iptunnel_handle_offloads(skb, SKB_GSO_IPXIP6))
1383                 return -1;
1384
1385         skb_set_inner_ipproto(skb, protocol);
1386
1387         err = ip6_tnl_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu,
1388                            protocol);
1389         if (err != 0) {
1390                 /* XXX: send ICMP error even if DF is not set. */
1391                 if (err == -EMSGSIZE)
1392                         switch (protocol) {
1393                         case IPPROTO_IPIP:
1394                                 icmp_ndo_send(skb, ICMP_DEST_UNREACH,
1395                                               ICMP_FRAG_NEEDED, htonl(mtu));
1396                                 break;
1397                         case IPPROTO_IPV6:
1398                                 icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
1399                                 break;
1400                         default:
1401                                 break;
1402                         }
1403                 return -1;
1404         }
1405
1406         return 0;
1407 }
1408
1409 static netdev_tx_t
1410 ip6_tnl_start_xmit(struct sk_buff *skb, struct net_device *dev)
1411 {
1412         struct ip6_tnl *t = netdev_priv(dev);
1413         struct net_device_stats *stats = &t->dev->stats;
1414         u8 ipproto;
1415         int ret;
1416
1417         if (!pskb_inet_may_pull(skb))
1418                 goto tx_err;
1419
1420         switch (skb->protocol) {
1421         case htons(ETH_P_IP):
1422                 ipproto = IPPROTO_IPIP;
1423                 break;
1424         case htons(ETH_P_IPV6):
1425                 if (ip6_tnl_addr_conflict(t, ipv6_hdr(skb)))
1426                         goto tx_err;
1427                 ipproto = IPPROTO_IPV6;
1428                 break;
1429         case htons(ETH_P_MPLS_UC):
1430                 ipproto = IPPROTO_MPLS;
1431                 break;
1432         default:
1433                 goto tx_err;
1434         }
1435
1436         ret = ipxip6_tnl_xmit(skb, dev, ipproto);
1437         if (ret < 0)
1438                 goto tx_err;
1439
1440         return NETDEV_TX_OK;
1441
1442 tx_err:
1443         stats->tx_errors++;
1444         stats->tx_dropped++;
1445         kfree_skb(skb);
1446         return NETDEV_TX_OK;
1447 }
1448
1449 static void ip6_tnl_link_config(struct ip6_tnl *t)
1450 {
1451         struct net_device *dev = t->dev;
1452         struct net_device *tdev = NULL;
1453         struct __ip6_tnl_parm *p = &t->parms;
1454         struct flowi6 *fl6 = &t->fl.u.ip6;
1455         unsigned int mtu;
1456         int t_hlen;
1457
1458         __dev_addr_set(dev, &p->laddr, sizeof(struct in6_addr));
1459         memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr));
1460
1461         /* Set up flowi template */
1462         fl6->saddr = p->laddr;
1463         fl6->daddr = p->raddr;
1464         fl6->flowi6_oif = p->link;
1465         fl6->flowlabel = 0;
1466
1467         if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS))
1468                 fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo;
1469         if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL))
1470                 fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo;
1471
1472         p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET);
1473         p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr);
1474
1475         if (p->flags&IP6_TNL_F_CAP_XMIT && p->flags&IP6_TNL_F_CAP_RCV)
1476                 dev->flags |= IFF_POINTOPOINT;
1477         else
1478                 dev->flags &= ~IFF_POINTOPOINT;
1479
1480         t->tun_hlen = 0;
1481         t->hlen = t->encap_hlen + t->tun_hlen;
1482         t_hlen = t->hlen + sizeof(struct ipv6hdr);
1483
1484         if (p->flags & IP6_TNL_F_CAP_XMIT) {
1485                 int strict = (ipv6_addr_type(&p->raddr) &
1486                               (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL));
1487
1488                 struct rt6_info *rt = rt6_lookup(t->net,
1489                                                  &p->raddr, &p->laddr,
1490                                                  p->link, NULL, strict);
1491                 if (rt) {
1492                         tdev = rt->dst.dev;
1493                         ip6_rt_put(rt);
1494                 }
1495
1496                 if (!tdev && p->link)
1497                         tdev = __dev_get_by_index(t->net, p->link);
1498
1499                 if (tdev) {
1500                         dev->hard_header_len = tdev->hard_header_len + t_hlen;
1501                         mtu = min_t(unsigned int, tdev->mtu, IP6_MAX_MTU);
1502
1503                         dev->mtu = mtu - t_hlen;
1504                         if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1505                                 dev->mtu -= 8;
1506
1507                         if (dev->mtu < IPV6_MIN_MTU)
1508                                 dev->mtu = IPV6_MIN_MTU;
1509                 }
1510         }
1511 }
1512
1513 /**
1514  * ip6_tnl_change - update the tunnel parameters
1515  *   @t: tunnel to be changed
1516  *   @p: tunnel configuration parameters
1517  *
1518  * Description:
1519  *   ip6_tnl_change() updates the tunnel parameters
1520  **/
1521
1522 static int
1523 ip6_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p)
1524 {
1525         t->parms.laddr = p->laddr;
1526         t->parms.raddr = p->raddr;
1527         t->parms.flags = p->flags;
1528         t->parms.hop_limit = p->hop_limit;
1529         t->parms.encap_limit = p->encap_limit;
1530         t->parms.flowinfo = p->flowinfo;
1531         t->parms.link = p->link;
1532         t->parms.proto = p->proto;
1533         t->parms.fwmark = p->fwmark;
1534         dst_cache_reset(&t->dst_cache);
1535         ip6_tnl_link_config(t);
1536         return 0;
1537 }
1538
1539 static int ip6_tnl_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p)
1540 {
1541         struct net *net = t->net;
1542         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1543         int err;
1544
1545         ip6_tnl_unlink(ip6n, t);
1546         synchronize_net();
1547         err = ip6_tnl_change(t, p);
1548         ip6_tnl_link(ip6n, t);
1549         netdev_state_change(t->dev);
1550         return err;
1551 }
1552
1553 static int ip6_tnl0_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p)
1554 {
1555         /* for default tnl0 device allow to change only the proto */
1556         t->parms.proto = p->proto;
1557         netdev_state_change(t->dev);
1558         return 0;
1559 }
1560
1561 static void
1562 ip6_tnl_parm_from_user(struct __ip6_tnl_parm *p, const struct ip6_tnl_parm *u)
1563 {
1564         p->laddr = u->laddr;
1565         p->raddr = u->raddr;
1566         p->flags = u->flags;
1567         p->hop_limit = u->hop_limit;
1568         p->encap_limit = u->encap_limit;
1569         p->flowinfo = u->flowinfo;
1570         p->link = u->link;
1571         p->proto = u->proto;
1572         memcpy(p->name, u->name, sizeof(u->name));
1573 }
1574
1575 static void
1576 ip6_tnl_parm_to_user(struct ip6_tnl_parm *u, const struct __ip6_tnl_parm *p)
1577 {
1578         u->laddr = p->laddr;
1579         u->raddr = p->raddr;
1580         u->flags = p->flags;
1581         u->hop_limit = p->hop_limit;
1582         u->encap_limit = p->encap_limit;
1583         u->flowinfo = p->flowinfo;
1584         u->link = p->link;
1585         u->proto = p->proto;
1586         memcpy(u->name, p->name, sizeof(u->name));
1587 }
1588
1589 /**
1590  * ip6_tnl_siocdevprivate - configure ipv6 tunnels from userspace
1591  *   @dev: virtual device associated with tunnel
1592  *   @ifr: unused
1593  *   @data: parameters passed from userspace
1594  *   @cmd: command to be performed
1595  *
1596  * Description:
1597  *   ip6_tnl_ioctl() is used for managing IPv6 tunnels
1598  *   from userspace.
1599  *
1600  *   The possible commands are the following:
1601  *     %SIOCGETTUNNEL: get tunnel parameters for device
1602  *     %SIOCADDTUNNEL: add tunnel matching given tunnel parameters
1603  *     %SIOCCHGTUNNEL: change tunnel parameters to those given
1604  *     %SIOCDELTUNNEL: delete tunnel
1605  *
1606  *   The fallback device "ip6tnl0", created during module
1607  *   initialization, can be used for creating other tunnel devices.
1608  *
1609  * Return:
1610  *   0 on success,
1611  *   %-EFAULT if unable to copy data to or from userspace,
1612  *   %-EPERM if current process hasn't %CAP_NET_ADMIN set
1613  *   %-EINVAL if passed tunnel parameters are invalid,
1614  *   %-EEXIST if changing a tunnel's parameters would cause a conflict
1615  *   %-ENODEV if attempting to change or delete a nonexisting device
1616  **/
1617
1618 static int
1619 ip6_tnl_siocdevprivate(struct net_device *dev, struct ifreq *ifr,
1620                        void __user *data, int cmd)
1621 {
1622         int err = 0;
1623         struct ip6_tnl_parm p;
1624         struct __ip6_tnl_parm p1;
1625         struct ip6_tnl *t = netdev_priv(dev);
1626         struct net *net = t->net;
1627         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1628
1629         memset(&p1, 0, sizeof(p1));
1630
1631         switch (cmd) {
1632         case SIOCGETTUNNEL:
1633                 if (dev == ip6n->fb_tnl_dev) {
1634                         if (copy_from_user(&p, data, sizeof(p))) {
1635                                 err = -EFAULT;
1636                                 break;
1637                         }
1638                         ip6_tnl_parm_from_user(&p1, &p);
1639                         t = ip6_tnl_locate(net, &p1, 0);
1640                         if (IS_ERR(t))
1641                                 t = netdev_priv(dev);
1642                 } else {
1643                         memset(&p, 0, sizeof(p));
1644                 }
1645                 ip6_tnl_parm_to_user(&p, &t->parms);
1646                 if (copy_to_user(data, &p, sizeof(p)))
1647                         err = -EFAULT;
1648                 break;
1649         case SIOCADDTUNNEL:
1650         case SIOCCHGTUNNEL:
1651                 err = -EPERM;
1652                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1653                         break;
1654                 err = -EFAULT;
1655                 if (copy_from_user(&p, data, sizeof(p)))
1656                         break;
1657                 err = -EINVAL;
1658                 if (p.proto != IPPROTO_IPV6 && p.proto != IPPROTO_IPIP &&
1659                     p.proto != 0)
1660                         break;
1661                 ip6_tnl_parm_from_user(&p1, &p);
1662                 t = ip6_tnl_locate(net, &p1, cmd == SIOCADDTUNNEL);
1663                 if (cmd == SIOCCHGTUNNEL) {
1664                         if (!IS_ERR(t)) {
1665                                 if (t->dev != dev) {
1666                                         err = -EEXIST;
1667                                         break;
1668                                 }
1669                         } else
1670                                 t = netdev_priv(dev);
1671                         if (dev == ip6n->fb_tnl_dev)
1672                                 err = ip6_tnl0_update(t, &p1);
1673                         else
1674                                 err = ip6_tnl_update(t, &p1);
1675                 }
1676                 if (!IS_ERR(t)) {
1677                         err = 0;
1678                         ip6_tnl_parm_to_user(&p, &t->parms);
1679                         if (copy_to_user(data, &p, sizeof(p)))
1680                                 err = -EFAULT;
1681
1682                 } else {
1683                         err = PTR_ERR(t);
1684                 }
1685                 break;
1686         case SIOCDELTUNNEL:
1687                 err = -EPERM;
1688                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1689                         break;
1690
1691                 if (dev == ip6n->fb_tnl_dev) {
1692                         err = -EFAULT;
1693                         if (copy_from_user(&p, data, sizeof(p)))
1694                                 break;
1695                         err = -ENOENT;
1696                         ip6_tnl_parm_from_user(&p1, &p);
1697                         t = ip6_tnl_locate(net, &p1, 0);
1698                         if (IS_ERR(t))
1699                                 break;
1700                         err = -EPERM;
1701                         if (t->dev == ip6n->fb_tnl_dev)
1702                                 break;
1703                         dev = t->dev;
1704                 }
1705                 err = 0;
1706                 unregister_netdevice(dev);
1707                 break;
1708         default:
1709                 err = -EINVAL;
1710         }
1711         return err;
1712 }
1713
1714 /**
1715  * ip6_tnl_change_mtu - change mtu manually for tunnel device
1716  *   @dev: virtual device associated with tunnel
1717  *   @new_mtu: the new mtu
1718  *
1719  * Return:
1720  *   0 on success,
1721  *   %-EINVAL if mtu too small
1722  **/
1723
1724 int ip6_tnl_change_mtu(struct net_device *dev, int new_mtu)
1725 {
1726         struct ip6_tnl *tnl = netdev_priv(dev);
1727
1728         if (tnl->parms.proto == IPPROTO_IPV6) {
1729                 if (new_mtu < IPV6_MIN_MTU)
1730                         return -EINVAL;
1731         } else {
1732                 if (new_mtu < ETH_MIN_MTU)
1733                         return -EINVAL;
1734         }
1735         if (tnl->parms.proto == IPPROTO_IPV6 || tnl->parms.proto == 0) {
1736                 if (new_mtu > IP6_MAX_MTU - dev->hard_header_len)
1737                         return -EINVAL;
1738         } else {
1739                 if (new_mtu > IP_MAX_MTU - dev->hard_header_len)
1740                         return -EINVAL;
1741         }
1742         dev->mtu = new_mtu;
1743         return 0;
1744 }
1745 EXPORT_SYMBOL(ip6_tnl_change_mtu);
1746
1747 int ip6_tnl_get_iflink(const struct net_device *dev)
1748 {
1749         struct ip6_tnl *t = netdev_priv(dev);
1750
1751         return t->parms.link;
1752 }
1753 EXPORT_SYMBOL(ip6_tnl_get_iflink);
1754
1755 int ip6_tnl_encap_add_ops(const struct ip6_tnl_encap_ops *ops,
1756                           unsigned int num)
1757 {
1758         if (num >= MAX_IPTUN_ENCAP_OPS)
1759                 return -ERANGE;
1760
1761         return !cmpxchg((const struct ip6_tnl_encap_ops **)
1762                         &ip6tun_encaps[num],
1763                         NULL, ops) ? 0 : -1;
1764 }
1765 EXPORT_SYMBOL(ip6_tnl_encap_add_ops);
1766
1767 int ip6_tnl_encap_del_ops(const struct ip6_tnl_encap_ops *ops,
1768                           unsigned int num)
1769 {
1770         int ret;
1771
1772         if (num >= MAX_IPTUN_ENCAP_OPS)
1773                 return -ERANGE;
1774
1775         ret = (cmpxchg((const struct ip6_tnl_encap_ops **)
1776                        &ip6tun_encaps[num],
1777                        ops, NULL) == ops) ? 0 : -1;
1778
1779         synchronize_net();
1780
1781         return ret;
1782 }
1783 EXPORT_SYMBOL(ip6_tnl_encap_del_ops);
1784
1785 int ip6_tnl_encap_setup(struct ip6_tnl *t,
1786                         struct ip_tunnel_encap *ipencap)
1787 {
1788         int hlen;
1789
1790         memset(&t->encap, 0, sizeof(t->encap));
1791
1792         hlen = ip6_encap_hlen(ipencap);
1793         if (hlen < 0)
1794                 return hlen;
1795
1796         t->encap.type = ipencap->type;
1797         t->encap.sport = ipencap->sport;
1798         t->encap.dport = ipencap->dport;
1799         t->encap.flags = ipencap->flags;
1800
1801         t->encap_hlen = hlen;
1802         t->hlen = t->encap_hlen + t->tun_hlen;
1803
1804         return 0;
1805 }
1806 EXPORT_SYMBOL_GPL(ip6_tnl_encap_setup);
1807
1808 static const struct net_device_ops ip6_tnl_netdev_ops = {
1809         .ndo_init       = ip6_tnl_dev_init,
1810         .ndo_uninit     = ip6_tnl_dev_uninit,
1811         .ndo_start_xmit = ip6_tnl_start_xmit,
1812         .ndo_siocdevprivate = ip6_tnl_siocdevprivate,
1813         .ndo_change_mtu = ip6_tnl_change_mtu,
1814         .ndo_get_stats64 = dev_get_tstats64,
1815         .ndo_get_iflink = ip6_tnl_get_iflink,
1816 };
1817
1818 #define IPXIPX_FEATURES (NETIF_F_SG |           \
1819                          NETIF_F_FRAGLIST |     \
1820                          NETIF_F_HIGHDMA |      \
1821                          NETIF_F_GSO_SOFTWARE | \
1822                          NETIF_F_HW_CSUM)
1823
1824 /**
1825  * ip6_tnl_dev_setup - setup virtual tunnel device
1826  *   @dev: virtual device associated with tunnel
1827  *
1828  * Description:
1829  *   Initialize function pointers and device parameters
1830  **/
1831
1832 static void ip6_tnl_dev_setup(struct net_device *dev)
1833 {
1834         dev->netdev_ops = &ip6_tnl_netdev_ops;
1835         dev->header_ops = &ip_tunnel_header_ops;
1836         dev->needs_free_netdev = true;
1837         dev->priv_destructor = ip6_dev_free;
1838
1839         dev->type = ARPHRD_TUNNEL6;
1840         dev->flags |= IFF_NOARP;
1841         dev->addr_len = sizeof(struct in6_addr);
1842         dev->features |= NETIF_F_LLTX;
1843         netif_keep_dst(dev);
1844
1845         dev->features           |= IPXIPX_FEATURES;
1846         dev->hw_features        |= IPXIPX_FEATURES;
1847
1848         /* This perm addr will be used as interface identifier by IPv6 */
1849         dev->addr_assign_type = NET_ADDR_RANDOM;
1850         eth_random_addr(dev->perm_addr);
1851 }
1852
1853
1854 /**
1855  * ip6_tnl_dev_init_gen - general initializer for all tunnel devices
1856  *   @dev: virtual device associated with tunnel
1857  **/
1858
1859 static inline int
1860 ip6_tnl_dev_init_gen(struct net_device *dev)
1861 {
1862         struct ip6_tnl *t = netdev_priv(dev);
1863         int ret;
1864         int t_hlen;
1865
1866         t->dev = dev;
1867         t->net = dev_net(dev);
1868         dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1869         if (!dev->tstats)
1870                 return -ENOMEM;
1871
1872         ret = dst_cache_init(&t->dst_cache, GFP_KERNEL);
1873         if (ret)
1874                 goto free_stats;
1875
1876         ret = gro_cells_init(&t->gro_cells, dev);
1877         if (ret)
1878                 goto destroy_dst;
1879
1880         t->tun_hlen = 0;
1881         t->hlen = t->encap_hlen + t->tun_hlen;
1882         t_hlen = t->hlen + sizeof(struct ipv6hdr);
1883
1884         dev->type = ARPHRD_TUNNEL6;
1885         dev->hard_header_len = LL_MAX_HEADER + t_hlen;
1886         dev->mtu = ETH_DATA_LEN - t_hlen;
1887         if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1888                 dev->mtu -= 8;
1889         dev->min_mtu = ETH_MIN_MTU;
1890         dev->max_mtu = IP6_MAX_MTU - dev->hard_header_len;
1891
1892         dev_hold_track(dev, &t->dev_tracker, GFP_KERNEL);
1893         return 0;
1894
1895 destroy_dst:
1896         dst_cache_destroy(&t->dst_cache);
1897 free_stats:
1898         free_percpu(dev->tstats);
1899         dev->tstats = NULL;
1900
1901         return ret;
1902 }
1903
1904 /**
1905  * ip6_tnl_dev_init - initializer for all non fallback tunnel devices
1906  *   @dev: virtual device associated with tunnel
1907  **/
1908
1909 static int ip6_tnl_dev_init(struct net_device *dev)
1910 {
1911         struct ip6_tnl *t = netdev_priv(dev);
1912         int err = ip6_tnl_dev_init_gen(dev);
1913
1914         if (err)
1915                 return err;
1916         ip6_tnl_link_config(t);
1917         if (t->parms.collect_md)
1918                 netif_keep_dst(dev);
1919         return 0;
1920 }
1921
1922 /**
1923  * ip6_fb_tnl_dev_init - initializer for fallback tunnel device
1924  *   @dev: fallback device
1925  *
1926  * Return: 0
1927  **/
1928
1929 static int __net_init ip6_fb_tnl_dev_init(struct net_device *dev)
1930 {
1931         struct ip6_tnl *t = netdev_priv(dev);
1932         struct net *net = dev_net(dev);
1933         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1934
1935         t->parms.proto = IPPROTO_IPV6;
1936
1937         rcu_assign_pointer(ip6n->tnls_wc[0], t);
1938         return 0;
1939 }
1940
1941 static int ip6_tnl_validate(struct nlattr *tb[], struct nlattr *data[],
1942                             struct netlink_ext_ack *extack)
1943 {
1944         u8 proto;
1945
1946         if (!data || !data[IFLA_IPTUN_PROTO])
1947                 return 0;
1948
1949         proto = nla_get_u8(data[IFLA_IPTUN_PROTO]);
1950         if (proto != IPPROTO_IPV6 &&
1951             proto != IPPROTO_IPIP &&
1952             proto != 0)
1953                 return -EINVAL;
1954
1955         return 0;
1956 }
1957
1958 static void ip6_tnl_netlink_parms(struct nlattr *data[],
1959                                   struct __ip6_tnl_parm *parms)
1960 {
1961         memset(parms, 0, sizeof(*parms));
1962
1963         if (!data)
1964                 return;
1965
1966         if (data[IFLA_IPTUN_LINK])
1967                 parms->link = nla_get_u32(data[IFLA_IPTUN_LINK]);
1968
1969         if (data[IFLA_IPTUN_LOCAL])
1970                 parms->laddr = nla_get_in6_addr(data[IFLA_IPTUN_LOCAL]);
1971
1972         if (data[IFLA_IPTUN_REMOTE])
1973                 parms->raddr = nla_get_in6_addr(data[IFLA_IPTUN_REMOTE]);
1974
1975         if (data[IFLA_IPTUN_TTL])
1976                 parms->hop_limit = nla_get_u8(data[IFLA_IPTUN_TTL]);
1977
1978         if (data[IFLA_IPTUN_ENCAP_LIMIT])
1979                 parms->encap_limit = nla_get_u8(data[IFLA_IPTUN_ENCAP_LIMIT]);
1980
1981         if (data[IFLA_IPTUN_FLOWINFO])
1982                 parms->flowinfo = nla_get_be32(data[IFLA_IPTUN_FLOWINFO]);
1983
1984         if (data[IFLA_IPTUN_FLAGS])
1985                 parms->flags = nla_get_u32(data[IFLA_IPTUN_FLAGS]);
1986
1987         if (data[IFLA_IPTUN_PROTO])
1988                 parms->proto = nla_get_u8(data[IFLA_IPTUN_PROTO]);
1989
1990         if (data[IFLA_IPTUN_COLLECT_METADATA])
1991                 parms->collect_md = true;
1992
1993         if (data[IFLA_IPTUN_FWMARK])
1994                 parms->fwmark = nla_get_u32(data[IFLA_IPTUN_FWMARK]);
1995 }
1996
1997 static bool ip6_tnl_netlink_encap_parms(struct nlattr *data[],
1998                                         struct ip_tunnel_encap *ipencap)
1999 {
2000         bool ret = false;
2001
2002         memset(ipencap, 0, sizeof(*ipencap));
2003
2004         if (!data)
2005                 return ret;
2006
2007         if (data[IFLA_IPTUN_ENCAP_TYPE]) {
2008                 ret = true;
2009                 ipencap->type = nla_get_u16(data[IFLA_IPTUN_ENCAP_TYPE]);
2010         }
2011
2012         if (data[IFLA_IPTUN_ENCAP_FLAGS]) {
2013                 ret = true;
2014                 ipencap->flags = nla_get_u16(data[IFLA_IPTUN_ENCAP_FLAGS]);
2015         }
2016
2017         if (data[IFLA_IPTUN_ENCAP_SPORT]) {
2018                 ret = true;
2019                 ipencap->sport = nla_get_be16(data[IFLA_IPTUN_ENCAP_SPORT]);
2020         }
2021
2022         if (data[IFLA_IPTUN_ENCAP_DPORT]) {
2023                 ret = true;
2024                 ipencap->dport = nla_get_be16(data[IFLA_IPTUN_ENCAP_DPORT]);
2025         }
2026
2027         return ret;
2028 }
2029
2030 static int ip6_tnl_newlink(struct net *src_net, struct net_device *dev,
2031                            struct nlattr *tb[], struct nlattr *data[],
2032                            struct netlink_ext_ack *extack)
2033 {
2034         struct net *net = dev_net(dev);
2035         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
2036         struct ip_tunnel_encap ipencap;
2037         struct ip6_tnl *nt, *t;
2038         int err;
2039
2040         nt = netdev_priv(dev);
2041
2042         if (ip6_tnl_netlink_encap_parms(data, &ipencap)) {
2043                 err = ip6_tnl_encap_setup(nt, &ipencap);
2044                 if (err < 0)
2045                         return err;
2046         }
2047
2048         ip6_tnl_netlink_parms(data, &nt->parms);
2049
2050         if (nt->parms.collect_md) {
2051                 if (rtnl_dereference(ip6n->collect_md_tun))
2052                         return -EEXIST;
2053         } else {
2054                 t = ip6_tnl_locate(net, &nt->parms, 0);
2055                 if (!IS_ERR(t))
2056                         return -EEXIST;
2057         }
2058
2059         err = ip6_tnl_create2(dev);
2060         if (!err && tb[IFLA_MTU])
2061                 ip6_tnl_change_mtu(dev, nla_get_u32(tb[IFLA_MTU]));
2062
2063         return err;
2064 }
2065
2066 static int ip6_tnl_changelink(struct net_device *dev, struct nlattr *tb[],
2067                               struct nlattr *data[],
2068                               struct netlink_ext_ack *extack)
2069 {
2070         struct ip6_tnl *t = netdev_priv(dev);
2071         struct __ip6_tnl_parm p;
2072         struct net *net = t->net;
2073         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
2074         struct ip_tunnel_encap ipencap;
2075
2076         if (dev == ip6n->fb_tnl_dev)
2077                 return -EINVAL;
2078
2079         if (ip6_tnl_netlink_encap_parms(data, &ipencap)) {
2080                 int err = ip6_tnl_encap_setup(t, &ipencap);
2081
2082                 if (err < 0)
2083                         return err;
2084         }
2085         ip6_tnl_netlink_parms(data, &p);
2086         if (p.collect_md)
2087                 return -EINVAL;
2088
2089         t = ip6_tnl_locate(net, &p, 0);
2090         if (!IS_ERR(t)) {
2091                 if (t->dev != dev)
2092                         return -EEXIST;
2093         } else
2094                 t = netdev_priv(dev);
2095
2096         return ip6_tnl_update(t, &p);
2097 }
2098
2099 static void ip6_tnl_dellink(struct net_device *dev, struct list_head *head)
2100 {
2101         struct net *net = dev_net(dev);
2102         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
2103
2104         if (dev != ip6n->fb_tnl_dev)
2105                 unregister_netdevice_queue(dev, head);
2106 }
2107
2108 static size_t ip6_tnl_get_size(const struct net_device *dev)
2109 {
2110         return
2111                 /* IFLA_IPTUN_LINK */
2112                 nla_total_size(4) +
2113                 /* IFLA_IPTUN_LOCAL */
2114                 nla_total_size(sizeof(struct in6_addr)) +
2115                 /* IFLA_IPTUN_REMOTE */
2116                 nla_total_size(sizeof(struct in6_addr)) +
2117                 /* IFLA_IPTUN_TTL */
2118                 nla_total_size(1) +
2119                 /* IFLA_IPTUN_ENCAP_LIMIT */
2120                 nla_total_size(1) +
2121                 /* IFLA_IPTUN_FLOWINFO */
2122                 nla_total_size(4) +
2123                 /* IFLA_IPTUN_FLAGS */
2124                 nla_total_size(4) +
2125                 /* IFLA_IPTUN_PROTO */
2126                 nla_total_size(1) +
2127                 /* IFLA_IPTUN_ENCAP_TYPE */
2128                 nla_total_size(2) +
2129                 /* IFLA_IPTUN_ENCAP_FLAGS */
2130                 nla_total_size(2) +
2131                 /* IFLA_IPTUN_ENCAP_SPORT */
2132                 nla_total_size(2) +
2133                 /* IFLA_IPTUN_ENCAP_DPORT */
2134                 nla_total_size(2) +
2135                 /* IFLA_IPTUN_COLLECT_METADATA */
2136                 nla_total_size(0) +
2137                 /* IFLA_IPTUN_FWMARK */
2138                 nla_total_size(4) +
2139                 0;
2140 }
2141
2142 static int ip6_tnl_fill_info(struct sk_buff *skb, const struct net_device *dev)
2143 {
2144         struct ip6_tnl *tunnel = netdev_priv(dev);
2145         struct __ip6_tnl_parm *parm = &tunnel->parms;
2146
2147         if (nla_put_u32(skb, IFLA_IPTUN_LINK, parm->link) ||
2148             nla_put_in6_addr(skb, IFLA_IPTUN_LOCAL, &parm->laddr) ||
2149             nla_put_in6_addr(skb, IFLA_IPTUN_REMOTE, &parm->raddr) ||
2150             nla_put_u8(skb, IFLA_IPTUN_TTL, parm->hop_limit) ||
2151             nla_put_u8(skb, IFLA_IPTUN_ENCAP_LIMIT, parm->encap_limit) ||
2152             nla_put_be32(skb, IFLA_IPTUN_FLOWINFO, parm->flowinfo) ||
2153             nla_put_u32(skb, IFLA_IPTUN_FLAGS, parm->flags) ||
2154             nla_put_u8(skb, IFLA_IPTUN_PROTO, parm->proto) ||
2155             nla_put_u32(skb, IFLA_IPTUN_FWMARK, parm->fwmark))
2156                 goto nla_put_failure;
2157
2158         if (nla_put_u16(skb, IFLA_IPTUN_ENCAP_TYPE, tunnel->encap.type) ||
2159             nla_put_be16(skb, IFLA_IPTUN_ENCAP_SPORT, tunnel->encap.sport) ||
2160             nla_put_be16(skb, IFLA_IPTUN_ENCAP_DPORT, tunnel->encap.dport) ||
2161             nla_put_u16(skb, IFLA_IPTUN_ENCAP_FLAGS, tunnel->encap.flags))
2162                 goto nla_put_failure;
2163
2164         if (parm->collect_md)
2165                 if (nla_put_flag(skb, IFLA_IPTUN_COLLECT_METADATA))
2166                         goto nla_put_failure;
2167
2168         return 0;
2169
2170 nla_put_failure:
2171         return -EMSGSIZE;
2172 }
2173
2174 struct net *ip6_tnl_get_link_net(const struct net_device *dev)
2175 {
2176         struct ip6_tnl *tunnel = netdev_priv(dev);
2177
2178         return tunnel->net;
2179 }
2180 EXPORT_SYMBOL(ip6_tnl_get_link_net);
2181
2182 static const struct nla_policy ip6_tnl_policy[IFLA_IPTUN_MAX + 1] = {
2183         [IFLA_IPTUN_LINK]               = { .type = NLA_U32 },
2184         [IFLA_IPTUN_LOCAL]              = { .len = sizeof(struct in6_addr) },
2185         [IFLA_IPTUN_REMOTE]             = { .len = sizeof(struct in6_addr) },
2186         [IFLA_IPTUN_TTL]                = { .type = NLA_U8 },
2187         [IFLA_IPTUN_ENCAP_LIMIT]        = { .type = NLA_U8 },
2188         [IFLA_IPTUN_FLOWINFO]           = { .type = NLA_U32 },
2189         [IFLA_IPTUN_FLAGS]              = { .type = NLA_U32 },
2190         [IFLA_IPTUN_PROTO]              = { .type = NLA_U8 },
2191         [IFLA_IPTUN_ENCAP_TYPE]         = { .type = NLA_U16 },
2192         [IFLA_IPTUN_ENCAP_FLAGS]        = { .type = NLA_U16 },
2193         [IFLA_IPTUN_ENCAP_SPORT]        = { .type = NLA_U16 },
2194         [IFLA_IPTUN_ENCAP_DPORT]        = { .type = NLA_U16 },
2195         [IFLA_IPTUN_COLLECT_METADATA]   = { .type = NLA_FLAG },
2196         [IFLA_IPTUN_FWMARK]             = { .type = NLA_U32 },
2197 };
2198
2199 static struct rtnl_link_ops ip6_link_ops __read_mostly = {
2200         .kind           = "ip6tnl",
2201         .maxtype        = IFLA_IPTUN_MAX,
2202         .policy         = ip6_tnl_policy,
2203         .priv_size      = sizeof(struct ip6_tnl),
2204         .setup          = ip6_tnl_dev_setup,
2205         .validate       = ip6_tnl_validate,
2206         .newlink        = ip6_tnl_newlink,
2207         .changelink     = ip6_tnl_changelink,
2208         .dellink        = ip6_tnl_dellink,
2209         .get_size       = ip6_tnl_get_size,
2210         .fill_info      = ip6_tnl_fill_info,
2211         .get_link_net   = ip6_tnl_get_link_net,
2212 };
2213
2214 static struct xfrm6_tunnel ip4ip6_handler __read_mostly = {
2215         .handler        = ip4ip6_rcv,
2216         .err_handler    = ip4ip6_err,
2217         .priority       =       1,
2218 };
2219
2220 static struct xfrm6_tunnel ip6ip6_handler __read_mostly = {
2221         .handler        = ip6ip6_rcv,
2222         .err_handler    = ip6ip6_err,
2223         .priority       =       1,
2224 };
2225
2226 static struct xfrm6_tunnel mplsip6_handler __read_mostly = {
2227         .handler        = mplsip6_rcv,
2228         .err_handler    = mplsip6_err,
2229         .priority       =       1,
2230 };
2231
2232 static void __net_exit ip6_tnl_destroy_tunnels(struct net *net, struct list_head *list)
2233 {
2234         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
2235         struct net_device *dev, *aux;
2236         int h;
2237         struct ip6_tnl *t;
2238
2239         for_each_netdev_safe(net, dev, aux)
2240                 if (dev->rtnl_link_ops == &ip6_link_ops)
2241                         unregister_netdevice_queue(dev, list);
2242
2243         for (h = 0; h < IP6_TUNNEL_HASH_SIZE; h++) {
2244                 t = rtnl_dereference(ip6n->tnls_r_l[h]);
2245                 while (t) {
2246                         /* If dev is in the same netns, it has already
2247                          * been added to the list by the previous loop.
2248                          */
2249                         if (!net_eq(dev_net(t->dev), net))
2250                                 unregister_netdevice_queue(t->dev, list);
2251                         t = rtnl_dereference(t->next);
2252                 }
2253         }
2254
2255         t = rtnl_dereference(ip6n->tnls_wc[0]);
2256         while (t) {
2257                 /* If dev is in the same netns, it has already
2258                  * been added to the list by the previous loop.
2259                  */
2260                 if (!net_eq(dev_net(t->dev), net))
2261                         unregister_netdevice_queue(t->dev, list);
2262                 t = rtnl_dereference(t->next);
2263         }
2264 }
2265
2266 static int __net_init ip6_tnl_init_net(struct net *net)
2267 {
2268         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
2269         struct ip6_tnl *t = NULL;
2270         int err;
2271
2272         ip6n->tnls[0] = ip6n->tnls_wc;
2273         ip6n->tnls[1] = ip6n->tnls_r_l;
2274
2275         if (!net_has_fallback_tunnels(net))
2276                 return 0;
2277         err = -ENOMEM;
2278         ip6n->fb_tnl_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6tnl0",
2279                                         NET_NAME_UNKNOWN, ip6_tnl_dev_setup);
2280
2281         if (!ip6n->fb_tnl_dev)
2282                 goto err_alloc_dev;
2283         dev_net_set(ip6n->fb_tnl_dev, net);
2284         ip6n->fb_tnl_dev->rtnl_link_ops = &ip6_link_ops;
2285         /* FB netdevice is special: we have one, and only one per netns.
2286          * Allowing to move it to another netns is clearly unsafe.
2287          */
2288         ip6n->fb_tnl_dev->features |= NETIF_F_NETNS_LOCAL;
2289
2290         err = ip6_fb_tnl_dev_init(ip6n->fb_tnl_dev);
2291         if (err < 0)
2292                 goto err_register;
2293
2294         err = register_netdev(ip6n->fb_tnl_dev);
2295         if (err < 0)
2296                 goto err_register;
2297
2298         t = netdev_priv(ip6n->fb_tnl_dev);
2299
2300         strcpy(t->parms.name, ip6n->fb_tnl_dev->name);
2301         return 0;
2302
2303 err_register:
2304         free_netdev(ip6n->fb_tnl_dev);
2305 err_alloc_dev:
2306         return err;
2307 }
2308
2309 static void __net_exit ip6_tnl_exit_batch_net(struct list_head *net_list)
2310 {
2311         struct net *net;
2312         LIST_HEAD(list);
2313
2314         rtnl_lock();
2315         list_for_each_entry(net, net_list, exit_list)
2316                 ip6_tnl_destroy_tunnels(net, &list);
2317         unregister_netdevice_many(&list);
2318         rtnl_unlock();
2319 }
2320
2321 static struct pernet_operations ip6_tnl_net_ops = {
2322         .init = ip6_tnl_init_net,
2323         .exit_batch = ip6_tnl_exit_batch_net,
2324         .id   = &ip6_tnl_net_id,
2325         .size = sizeof(struct ip6_tnl_net),
2326 };
2327
2328 /**
2329  * ip6_tunnel_init - register protocol and reserve needed resources
2330  *
2331  * Return: 0 on success
2332  **/
2333
2334 static int __init ip6_tunnel_init(void)
2335 {
2336         int  err;
2337
2338         if (!ipv6_mod_enabled())
2339                 return -EOPNOTSUPP;
2340
2341         err = register_pernet_device(&ip6_tnl_net_ops);
2342         if (err < 0)
2343                 goto out_pernet;
2344
2345         err = xfrm6_tunnel_register(&ip4ip6_handler, AF_INET);
2346         if (err < 0) {
2347                 pr_err("%s: can't register ip4ip6\n", __func__);
2348                 goto out_ip4ip6;
2349         }
2350
2351         err = xfrm6_tunnel_register(&ip6ip6_handler, AF_INET6);
2352         if (err < 0) {
2353                 pr_err("%s: can't register ip6ip6\n", __func__);
2354                 goto out_ip6ip6;
2355         }
2356
2357         if (ip6_tnl_mpls_supported()) {
2358                 err = xfrm6_tunnel_register(&mplsip6_handler, AF_MPLS);
2359                 if (err < 0) {
2360                         pr_err("%s: can't register mplsip6\n", __func__);
2361                         goto out_mplsip6;
2362                 }
2363         }
2364
2365         err = rtnl_link_register(&ip6_link_ops);
2366         if (err < 0)
2367                 goto rtnl_link_failed;
2368
2369         return 0;
2370
2371 rtnl_link_failed:
2372         if (ip6_tnl_mpls_supported())
2373                 xfrm6_tunnel_deregister(&mplsip6_handler, AF_MPLS);
2374 out_mplsip6:
2375         xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6);
2376 out_ip6ip6:
2377         xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET);
2378 out_ip4ip6:
2379         unregister_pernet_device(&ip6_tnl_net_ops);
2380 out_pernet:
2381         return err;
2382 }
2383
2384 /**
2385  * ip6_tunnel_cleanup - free resources and unregister protocol
2386  **/
2387
2388 static void __exit ip6_tunnel_cleanup(void)
2389 {
2390         rtnl_link_unregister(&ip6_link_ops);
2391         if (xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET))
2392                 pr_info("%s: can't deregister ip4ip6\n", __func__);
2393
2394         if (xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6))
2395                 pr_info("%s: can't deregister ip6ip6\n", __func__);
2396
2397         if (ip6_tnl_mpls_supported() &&
2398             xfrm6_tunnel_deregister(&mplsip6_handler, AF_MPLS))
2399                 pr_info("%s: can't deregister mplsip6\n", __func__);
2400         unregister_pernet_device(&ip6_tnl_net_ops);
2401 }
2402
2403 module_init(ip6_tunnel_init);
2404 module_exit(ip6_tunnel_cleanup);