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 static struct net_device_stats *ip6_get_stats(struct net_device *dev)
  98 {
  99         struct pcpu_sw_netstats tmp, sum = { 0 };
 100         int i;
 101
 102         for_each_possible_cpu(i) {
 103                 unsigned int start;
 104                 const struct pcpu_sw_netstats *tstats =
 105                                                    per_cpu_ptr(dev->tstats, i);
 106
 107                 do {
 108                         start = u64_stats_fetch_begin_irq(&tstats->syncp);
 109                         tmp.rx_packets = tstats->rx_packets;
 110                         tmp.rx_bytes = tstats->rx_bytes;
 111                         tmp.tx_packets = tstats->tx_packets;
 112                         tmp.tx_bytes =  tstats->tx_bytes;
 113                 } while (u64_stats_fetch_retry_irq(&tstats->syncp, start));
 114
 115                 sum.rx_packets += tmp.rx_packets;
 116                 sum.rx_bytes   += tmp.rx_bytes;
 117                 sum.tx_packets += tmp.tx_packets;
 118                 sum.tx_bytes   += tmp.tx_bytes;
 119         }
 120         dev->stats.rx_packets = sum.rx_packets;
 121         dev->stats.rx_bytes   = sum.rx_bytes;
 122         dev->stats.tx_packets = sum.tx_packets;
 123         dev->stats.tx_bytes   = sum.tx_bytes;
 124         return &dev->stats;
 125 }
 126
 127 #define for_each_ip6_tunnel_rcu(start) \
 128         for (t = rcu_dereference(start); t; t = rcu_dereference(t->next))
 129
 130 /**
 131  * ip6_tnl_lookup - fetch tunnel matching the end-point addresses
 132  *   @net: network namespace
 133  *   @link: ifindex of underlying interface
 134  *   @remote: the address of the tunnel exit-point
 135  *   @local: the address of the tunnel entry-point
 136  *
 137  * Return:
 138  *   tunnel matching given end-points if found,
 139  *   else fallback tunnel if its device is up,
 140  *   else %NULL
 141  **/
 142
 143 static struct ip6_tnl *
 144 ip6_tnl_lookup(struct net *net, int link,
 145                const struct in6_addr *remote, const struct in6_addr *local)
 146 {
 147         unsigned int hash = HASH(remote, local);
 148         struct ip6_tnl *t, *cand = NULL;
 149         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
 150         struct in6_addr any;
 151
 152         for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
 153                 if (!ipv6_addr_equal(local, &t->parms.laddr) ||
 154                     !ipv6_addr_equal(remote, &t->parms.raddr) ||
 155                     !(t->dev->flags & IFF_UP))
 156                         continue;
 157
 158                 if (link == t->parms.link)
 159                         return t;
 160                 else
 161                         cand = t;
 162         }
 163
 164         memset(&any, 0, sizeof(any));
 165         hash = HASH(&any, local);
 166         for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
 167                 if (!ipv6_addr_equal(local, &t->parms.laddr) ||
 168                     !ipv6_addr_any(&t->parms.raddr) ||
 169                     !(t->dev->flags & IFF_UP))
 170                         continue;
 171
 172                 if (link == t->parms.link)
 173                         return t;
 174                 else if (!cand)
 175                         cand = t;
 176         }
 177
 178         hash = HASH(remote, &any);
 179         for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
 180                 if (!ipv6_addr_equal(remote, &t->parms.raddr) ||
 181                     !ipv6_addr_any(&t->parms.laddr) ||
 182                     !(t->dev->flags & IFF_UP))
 183                         continue;
 184
 185                 if (link == t->parms.link)
 186                         return t;
 187                 else if (!cand)
 188                         cand = t;
 189         }
 190
 191         if (cand)
 192                 return cand;
 193
 194         t = rcu_dereference(ip6n->collect_md_tun);
 195         if (t && t->dev->flags & IFF_UP)
 196                 return t;
 197
 198         t = rcu_dereference(ip6n->tnls_wc[0]);
 199         if (t && (t->dev->flags & IFF_UP))
 200                 return t;
 201
 202         return NULL;
 203 }
 204
 205 /**
 206  * ip6_tnl_bucket - get head of list matching given tunnel parameters
 207  *   @p: parameters containing tunnel end-points
 208  *
 209  * Description:
 210  *   ip6_tnl_bucket() returns the head of the list matching the
 211  *   &struct in6_addr entries laddr and raddr in @p.
 212  *
 213  * Return: head of IPv6 tunnel list
 214  **/
 215
 216 static struct ip6_tnl __rcu **
 217 ip6_tnl_bucket(struct ip6_tnl_net *ip6n, const struct __ip6_tnl_parm *p)
 218 {
 219         const struct in6_addr *remote = &p->raddr;
 220         const struct in6_addr *local = &p->laddr;
 221         unsigned int h = 0;
 222         int prio = 0;
 223
 224         if (!ipv6_addr_any(remote) || !ipv6_addr_any(local)) {
 225                 prio = 1;
 226                 h = HASH(remote, local);
 227         }
 228         return &ip6n->tnls[prio][h];
 229 }
 230
 231 /**
 232  * ip6_tnl_link - add tunnel to hash table
 233  *   @t: tunnel to be added
 234  **/
 235
 236 static void
 237 ip6_tnl_link(struct ip6_tnl_net *ip6n, struct ip6_tnl *t)
 238 {
 239         struct ip6_tnl __rcu **tp = ip6_tnl_bucket(ip6n, &t->parms);
 240
 241         if (t->parms.collect_md)
 242                 rcu_assign_pointer(ip6n->collect_md_tun, t);
 243         rcu_assign_pointer(t->next , rtnl_dereference(*tp));
 244         rcu_assign_pointer(*tp, t);
 245 }
 246
 247 /**
 248  * ip6_tnl_unlink - remove tunnel from hash table
 249  *   @t: tunnel to be removed
 250  **/
 251
 252 static void
 253 ip6_tnl_unlink(struct ip6_tnl_net *ip6n, struct ip6_tnl *t)
 254 {
 255         struct ip6_tnl __rcu **tp;
 256         struct ip6_tnl *iter;
 257
 258         if (t->parms.collect_md)
 259                 rcu_assign_pointer(ip6n->collect_md_tun, NULL);
 260
 261         for (tp = ip6_tnl_bucket(ip6n, &t->parms);
 262              (iter = rtnl_dereference(*tp)) != NULL;
 263              tp = &iter->next) {
 264                 if (t == iter) {
 265                         rcu_assign_pointer(*tp, t->next);
 266                         break;
 267                 }
 268         }
 269 }
 270
 271 static void ip6_dev_free(struct net_device *dev)
 272 {
 273         struct ip6_tnl *t = netdev_priv(dev);
 274
 275         gro_cells_destroy(&t->gro_cells);
 276         dst_cache_destroy(&t->dst_cache);
 277         free_percpu(dev->tstats);
 278 }
 279
 280 static int ip6_tnl_create2(struct net_device *dev)
 281 {
 282         struct ip6_tnl *t = netdev_priv(dev);
 283         struct net *net = dev_net(dev);
 284         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
 285         int err;
 286
 287         t = netdev_priv(dev);
 288
 289         dev->rtnl_link_ops = &ip6_link_ops;
 290         err = register_netdevice(dev);
 291         if (err < 0)
 292                 goto out;
 293
 294         strcpy(t->parms.name, dev->name);
 295
 296         dev_hold(dev);
 297         ip6_tnl_link(ip6n, t);
 298         return 0;
 299
 300 out:
 301         return err;
 302 }
 303
 304 /**
 305  * ip6_tnl_create - create a new tunnel
 306  *   @net: network namespace
 307  *   @p: tunnel parameters
 308  *
 309  * Description:
 310  *   Create tunnel matching given parameters.
 311  *
 312  * Return:
 313  *   created tunnel or error pointer
 314  **/
 315
 316 static struct ip6_tnl *ip6_tnl_create(struct net *net, struct __ip6_tnl_parm *p)
 317 {
 318         struct net_device *dev;
 319         struct ip6_tnl *t;
 320         char name[IFNAMSIZ];
 321         int err = -E2BIG;
 322
 323         if (p->name[0]) {
 324                 if (!dev_valid_name(p->name))
 325                         goto failed;
 326                 strlcpy(name, p->name, IFNAMSIZ);
 327         } else {
 328                 sprintf(name, "ip6tnl%%d");
 329         }
 330         err = -ENOMEM;
 331         dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN,
 332                            ip6_tnl_dev_setup);
 333         if (!dev)
 334                 goto failed;
 335
 336         dev_net_set(dev, net);
 337
 338         t = netdev_priv(dev);
 339         t->parms = *p;
 340         t->net = dev_net(dev);
 341         err = ip6_tnl_create2(dev);
 342         if (err < 0)
 343                 goto failed_free;
 344
 345         return t;
 346
 347 failed_free:
 348         free_netdev(dev);
 349 failed:
 350         return ERR_PTR(err);
 351 }
 352
 353 /**
 354  * ip6_tnl_locate - find or create tunnel matching given parameters
 355  *   @net: network namespace
 356  *   @p: tunnel parameters
 357  *   @create: != 0 if allowed to create new tunnel if no match found
 358  *
 359  * Description:
 360  *   ip6_tnl_locate() first tries to locate an existing tunnel
 361  *   based on @parms. If this is unsuccessful, but @create is set a new
 362  *   tunnel device is created and registered for use.
 363  *
 364  * Return:
 365  *   matching tunnel or error pointer
 366  **/
 367
 368 static struct ip6_tnl *ip6_tnl_locate(struct net *net,
 369                 struct __ip6_tnl_parm *p, int create)
 370 {
 371         const struct in6_addr *remote = &p->raddr;
 372         const struct in6_addr *local = &p->laddr;
 373         struct ip6_tnl __rcu **tp;
 374         struct ip6_tnl *t;
 375         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
 376
 377         for (tp = ip6_tnl_bucket(ip6n, p);
 378              (t = rtnl_dereference(*tp)) != NULL;
 379              tp = &t->next) {
 380                 if (ipv6_addr_equal(local, &t->parms.laddr) &&
 381                     ipv6_addr_equal(remote, &t->parms.raddr) &&
 382                     p->link == t->parms.link) {
 383                         if (create)
 384                                 return ERR_PTR(-EEXIST);
 385
 386                         return t;
 387                 }
 388         }
 389         if (!create)
 390                 return ERR_PTR(-ENODEV);
 391         return ip6_tnl_create(net, p);
 392 }
 393
 394 /**
 395  * ip6_tnl_dev_uninit - tunnel device uninitializer
 396  *   @dev: the device to be destroyed
 397  *
 398  * Description:
 399  *   ip6_tnl_dev_uninit() removes tunnel from its list
 400  **/
 401
 402 static void
 403 ip6_tnl_dev_uninit(struct net_device *dev)
 404 {
 405         struct ip6_tnl *t = netdev_priv(dev);
 406         struct net *net = t->net;
 407         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
 408
 409         if (dev == ip6n->fb_tnl_dev)
 410                 RCU_INIT_POINTER(ip6n->tnls_wc[0], NULL);
 411         else
 412                 ip6_tnl_unlink(ip6n, t);
 413         dst_cache_reset(&t->dst_cache);
 414         dev_put(dev);
 415 }
 416
 417 /**
 418  * parse_tvl_tnl_enc_lim - handle encapsulation limit option
 419  *   @skb: received socket buffer
 420  *
 421  * Return:
 422  *   0 if none was found,
 423  *   else index to encapsulation limit
 424  **/
 425
 426 __u16 ip6_tnl_parse_tlv_enc_lim(struct sk_buff *skb, __u8 *raw)
 427 {
 428         const struct ipv6hdr *ipv6h = (const struct ipv6hdr *)raw;
 429         unsigned int nhoff = raw - skb->data;
 430         unsigned int off = nhoff + sizeof(*ipv6h);
 431         u8 next, nexthdr = ipv6h->nexthdr;
 432
 433         while (ipv6_ext_hdr(nexthdr) && nexthdr != NEXTHDR_NONE) {
 434                 struct ipv6_opt_hdr *hdr;
 435                 u16 optlen;
 436
 437                 if (!pskb_may_pull(skb, off + sizeof(*hdr)))
 438                         break;
 439
 440                 hdr = (struct ipv6_opt_hdr *)(skb->data + off);
 441                 if (nexthdr == NEXTHDR_FRAGMENT) {
 442                         struct frag_hdr *frag_hdr = (struct frag_hdr *) hdr;
 443                         if (frag_hdr->frag_off)
 444                                 break;
 445                         optlen = 8;
 446                 } else if (nexthdr == NEXTHDR_AUTH) {
 447                         optlen = ipv6_authlen(hdr);
 448                 } else {
 449                         optlen = ipv6_optlen(hdr);
 450                 }
 451                 /* cache hdr->nexthdr, since pskb_may_pull() might
 452                  * invalidate hdr
 453                  */
 454                 next = hdr->nexthdr;
 455                 if (nexthdr == NEXTHDR_DEST) {
 456                         u16 i = 2;
 457
 458                         /* Remember : hdr is no longer valid at this point. */
 459                         if (!pskb_may_pull(skb, off + optlen))
 460                                 break;
 461
 462                         while (1) {
 463                                 struct ipv6_tlv_tnl_enc_lim *tel;
 464
 465                                 /* No more room for encapsulation limit */
 466                                 if (i + sizeof(*tel) > optlen)
 467                                         break;
 468
 469                                 tel = (struct ipv6_tlv_tnl_enc_lim *)(skb->data + off + i);
 470                                 /* return index of option if found and valid */
 471                                 if (tel->type == IPV6_TLV_TNL_ENCAP_LIMIT &&
 472                                     tel->length == 1)
 473                                         return i + off - nhoff;
 474                                 /* else jump to next option */
 475                                 if (tel->type)
 476                                         i += tel->length + 2;
 477                                 else
 478                                         i++;
 479                         }
 480                 }
 481                 nexthdr = next;
 482                 off += optlen;
 483         }
 484         return 0;
 485 }
 486 EXPORT_SYMBOL(ip6_tnl_parse_tlv_enc_lim);
 487
 488 /**
 489  * ip6_tnl_err - tunnel error handler
 490  *
 491  * Description:
 492  *   ip6_tnl_err() should handle errors in the tunnel according
 493  *   to the specifications in RFC 2473.
 494  **/
 495
 496 static int
 497 ip6_tnl_err(struct sk_buff *skb, __u8 ipproto, struct inet6_skb_parm *opt,
 498             u8 *type, u8 *code, int *msg, __u32 *info, int offset)
 499 {
 500         const struct ipv6hdr *ipv6h = (const struct ipv6hdr *)skb->data;
 501         struct net *net = dev_net(skb->dev);
 502         u8 rel_type = ICMPV6_DEST_UNREACH;
 503         u8 rel_code = ICMPV6_ADDR_UNREACH;
 504         __u32 rel_info = 0;
 505         struct ip6_tnl *t;
 506         int err = -ENOENT;
 507         int rel_msg = 0;
 508         u8 tproto;
 509         __u16 len;
 510
 511         /* If the packet doesn't contain the original IPv6 header we are
 512            in trouble since we might need the source address for further
 513            processing of the error. */
 514
 515         rcu_read_lock();
 516         t = ip6_tnl_lookup(dev_net(skb->dev), skb->dev->ifindex, &ipv6h->daddr, &ipv6h->saddr);
 517         if (!t)
 518                 goto out;
 519
 520         tproto = READ_ONCE(t->parms.proto);
 521         if (tproto != ipproto && tproto != 0)
 522                 goto out;
 523
 524         err = 0;
 525
 526         switch (*type) {
 527         case ICMPV6_DEST_UNREACH:
 528                 net_dbg_ratelimited("%s: Path to destination invalid or inactive!\n",
 529                                     t->parms.name);
 530                 rel_msg = 1;
 531                 break;
 532         case ICMPV6_TIME_EXCEED:
 533                 if ((*code) == ICMPV6_EXC_HOPLIMIT) {
 534                         net_dbg_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n",
 535                                             t->parms.name);
 536                         rel_msg = 1;
 537                 }
 538                 break;
 539         case ICMPV6_PARAMPROB: {
 540                 struct ipv6_tlv_tnl_enc_lim *tel;
 541                 __u32 teli;
 542
 543                 teli = 0;
 544                 if ((*code) == ICMPV6_HDR_FIELD)
 545                         teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data);
 546
 547                 if (teli && teli == *info - 2) {
 548                         tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli];
 549                         if (tel->encap_limit == 0) {
 550                                 net_dbg_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n",
 551                                                     t->parms.name);
 552                                 rel_msg = 1;
 553                         }
 554                 } else {
 555                         net_dbg_ratelimited("%s: Recipient unable to parse tunneled packet!\n",
 556                                             t->parms.name);
 557                 }
 558                 break;
 559         }
 560         case ICMPV6_PKT_TOOBIG: {
 561                 __u32 mtu;
 562
 563                 ip6_update_pmtu(skb, net, htonl(*info), 0, 0,
 564                                 sock_net_uid(net, NULL));
 565                 mtu = *info - offset;
 566                 if (mtu < IPV6_MIN_MTU)
 567                         mtu = IPV6_MIN_MTU;
 568                 len = sizeof(*ipv6h) + ntohs(ipv6h->payload_len);
 569                 if (len > mtu) {
 570                         rel_type = ICMPV6_PKT_TOOBIG;
 571                         rel_code = 0;
 572                         rel_info = mtu;
 573                         rel_msg = 1;
 574                 }
 575                 break;
 576         }
 577         case NDISC_REDIRECT:
 578                 ip6_redirect(skb, net, skb->dev->ifindex, 0,
 579                              sock_net_uid(net, NULL));
 580                 break;
 581         }
 582
 583         *type = rel_type;
 584         *code = rel_code;
 585         *info = rel_info;
 586         *msg = rel_msg;
 587
 588 out:
 589         rcu_read_unlock();
 590         return err;
 591 }
 592
 593 static int
 594 ip4ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 595            u8 type, u8 code, int offset, __be32 info)
 596 {
 597         __u32 rel_info = ntohl(info);
 598         const struct iphdr *eiph;
 599         struct sk_buff *skb2;
 600         int err, rel_msg = 0;
 601         u8 rel_type = type;
 602         u8 rel_code = code;
 603         struct rtable *rt;
 604         struct flowi4 fl4;
 605
 606         err = ip6_tnl_err(skb, IPPROTO_IPIP, opt, &rel_type, &rel_code,
 607                           &rel_msg, &rel_info, offset);
 608         if (err < 0)
 609                 return err;
 610
 611         if (rel_msg == 0)
 612                 return 0;
 613
 614         switch (rel_type) {
 615         case ICMPV6_DEST_UNREACH:
 616                 if (rel_code != ICMPV6_ADDR_UNREACH)
 617                         return 0;
 618                 rel_type = ICMP_DEST_UNREACH;
 619                 rel_code = ICMP_HOST_UNREACH;
 620                 break;
 621         case ICMPV6_PKT_TOOBIG:
 622                 if (rel_code != 0)
 623                         return 0;
 624                 rel_type = ICMP_DEST_UNREACH;
 625                 rel_code = ICMP_FRAG_NEEDED;
 626                 break;
 627         default:
 628                 return 0;
 629         }
 630
 631         if (!pskb_may_pull(skb, offset + sizeof(struct iphdr)))
 632                 return 0;
 633
 634         skb2 = skb_clone(skb, GFP_ATOMIC);
 635         if (!skb2)
 636                 return 0;
 637
 638         skb_dst_drop(skb2);
 639
 640         skb_pull(skb2, offset);
 641         skb_reset_network_header(skb2);
 642         eiph = ip_hdr(skb2);
 643
 644         /* Try to guess incoming interface */
 645         rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL, eiph->saddr,
 646                                    0, 0, 0, IPPROTO_IPIP, RT_TOS(eiph->tos), 0);
 647         if (IS_ERR(rt))
 648                 goto out;
 649
 650         skb2->dev = rt->dst.dev;
 651         ip_rt_put(rt);
 652
 653         /* route "incoming" packet */
 654         if (rt->rt_flags & RTCF_LOCAL) {
 655                 rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL,
 656                                            eiph->daddr, eiph->saddr, 0, 0,
 657                                            IPPROTO_IPIP, RT_TOS(eiph->tos), 0);
 658                 if (IS_ERR(rt) || rt->dst.dev->type != ARPHRD_TUNNEL6) {
 659                         if (!IS_ERR(rt))
 660                                 ip_rt_put(rt);
 661                         goto out;
 662                 }
 663                 skb_dst_set(skb2, &rt->dst);
 664         } else {
 665                 if (ip_route_input(skb2, eiph->daddr, eiph->saddr, eiph->tos,
 666                                    skb2->dev) ||
 667                     skb_dst(skb2)->dev->type != ARPHRD_TUNNEL6)
 668                         goto out;
 669         }
 670
 671         /* change mtu on this route */
 672         if (rel_type == ICMP_DEST_UNREACH && rel_code == ICMP_FRAG_NEEDED) {
 673                 if (rel_info > dst_mtu(skb_dst(skb2)))
 674                         goto out;
 675
 676                 skb_dst_update_pmtu_no_confirm(skb2, rel_info);
 677         }
 678
 679         icmp_send(skb2, rel_type, rel_code, htonl(rel_info));
 680
 681 out:
 682         kfree_skb(skb2);
 683         return 0;
 684 }
 685
 686 static int
 687 ip6ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 688            u8 type, u8 code, int offset, __be32 info)
 689 {
 690         __u32 rel_info = ntohl(info);
 691         int err, rel_msg = 0;
 692         u8 rel_type = type;
 693         u8 rel_code = code;
 694
 695         err = ip6_tnl_err(skb, IPPROTO_IPV6, opt, &rel_type, &rel_code,
 696                           &rel_msg, &rel_info, offset);
 697         if (err < 0)
 698                 return err;
 699
 700         if (rel_msg && pskb_may_pull(skb, offset + sizeof(struct ipv6hdr))) {
 701                 struct rt6_info *rt;
 702                 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
 703
 704                 if (!skb2)
 705                         return 0;
 706
 707                 skb_dst_drop(skb2);
 708                 skb_pull(skb2, offset);
 709                 skb_reset_network_header(skb2);
 710
 711                 /* Try to guess incoming interface */
 712                 rt = rt6_lookup(dev_net(skb->dev), &ipv6_hdr(skb2)->saddr,
 713                                 NULL, 0, skb2, 0);
 714
 715                 if (rt && rt->dst.dev)
 716                         skb2->dev = rt->dst.dev;
 717
 718                 icmpv6_send(skb2, rel_type, rel_code, rel_info);
 719
 720                 ip6_rt_put(rt);
 721
 722                 kfree_skb(skb2);
 723         }
 724
 725         return 0;
 726 }
 727
 728 static int
 729 mplsip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 730             u8 type, u8 code, int offset, __be32 info)
 731 {
 732         __u32 rel_info = ntohl(info);
 733         int err, rel_msg = 0;
 734         u8 rel_type = type;
 735         u8 rel_code = code;
 736
 737         err = ip6_tnl_err(skb, IPPROTO_MPLS, opt, &rel_type, &rel_code,
 738                           &rel_msg, &rel_info, offset);
 739         return err;
 740 }
 741
 742 static int ip4ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t,
 743                                        const struct ipv6hdr *ipv6h,
 744                                        struct sk_buff *skb)
 745 {
 746         __u8 dsfield = ipv6_get_dsfield(ipv6h) & ~INET_ECN_MASK;
 747
 748         if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY)
 749                 ipv4_change_dsfield(ip_hdr(skb), INET_ECN_MASK, dsfield);
 750
 751         return IP6_ECN_decapsulate(ipv6h, skb);
 752 }
 753
 754 static int ip6ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t,
 755                                        const struct ipv6hdr *ipv6h,
 756                                        struct sk_buff *skb)
 757 {
 758         if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY)
 759                 ipv6_copy_dscp(ipv6_get_dsfield(ipv6h), ipv6_hdr(skb));
 760
 761         return IP6_ECN_decapsulate(ipv6h, skb);
 762 }
 763
 764 static inline int mplsip6_dscp_ecn_decapsulate(const struct ip6_tnl *t,
 765                                                const struct ipv6hdr *ipv6h,
 766                                                struct sk_buff *skb)
 767 {
 768         /* ECN is not supported in AF_MPLS */
 769         return 0;
 770 }
 771
 772 __u32 ip6_tnl_get_cap(struct ip6_tnl *t,
 773                              const struct in6_addr *laddr,
 774                              const struct in6_addr *raddr)
 775 {
 776         struct __ip6_tnl_parm *p = &t->parms;
 777         int ltype = ipv6_addr_type(laddr);
 778         int rtype = ipv6_addr_type(raddr);
 779         __u32 flags = 0;
 780
 781         if (ltype == IPV6_ADDR_ANY || rtype == IPV6_ADDR_ANY) {
 782                 flags = IP6_TNL_F_CAP_PER_PACKET;
 783         } else if (ltype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) &&
 784                    rtype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) &&
 785                    !((ltype|rtype) & IPV6_ADDR_LOOPBACK) &&
 786                    (!((ltype|rtype) & IPV6_ADDR_LINKLOCAL) || p->link)) {
 787                 if (ltype&IPV6_ADDR_UNICAST)
 788                         flags |= IP6_TNL_F_CAP_XMIT;
 789                 if (rtype&IPV6_ADDR_UNICAST)
 790                         flags |= IP6_TNL_F_CAP_RCV;
 791         }
 792         return flags;
 793 }
 794 EXPORT_SYMBOL(ip6_tnl_get_cap);
 795
 796 /* called with rcu_read_lock() */
 797 int ip6_tnl_rcv_ctl(struct ip6_tnl *t,
 798                                   const struct in6_addr *laddr,
 799                                   const struct in6_addr *raddr)
 800 {
 801         struct __ip6_tnl_parm *p = &t->parms;
 802         int ret = 0;
 803         struct net *net = t->net;
 804
 805         if ((p->flags & IP6_TNL_F_CAP_RCV) ||
 806             ((p->flags & IP6_TNL_F_CAP_PER_PACKET) &&
 807              (ip6_tnl_get_cap(t, laddr, raddr) & IP6_TNL_F_CAP_RCV))) {
 808                 struct net_device *ldev = NULL;
 809
 810                 if (p->link)
 811                         ldev = dev_get_by_index_rcu(net, p->link);
 812
 813                 if ((ipv6_addr_is_multicast(laddr) ||
 814                      likely(ipv6_chk_addr_and_flags(net, laddr, ldev, false,
 815                                                     0, IFA_F_TENTATIVE))) &&
 816                     ((p->flags & IP6_TNL_F_ALLOW_LOCAL_REMOTE) ||
 817                      likely(!ipv6_chk_addr_and_flags(net, raddr, ldev, true,
 818                                                      0, IFA_F_TENTATIVE))))
 819                         ret = 1;
 820         }
 821         return ret;
 822 }
 823 EXPORT_SYMBOL_GPL(ip6_tnl_rcv_ctl);
 824
 825 static int __ip6_tnl_rcv(struct ip6_tnl *tunnel, struct sk_buff *skb,
 826                          const struct tnl_ptk_info *tpi,
 827                          struct metadata_dst *tun_dst,
 828                          int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t,
 829                                                 const struct ipv6hdr *ipv6h,
 830                                                 struct sk_buff *skb),
 831                          bool log_ecn_err)
 832 {
 833         struct pcpu_sw_netstats *tstats;
 834         const struct ipv6hdr *ipv6h = ipv6_hdr(skb);
 835         int err;
 836
 837         if ((!(tpi->flags & TUNNEL_CSUM) &&
 838              (tunnel->parms.i_flags & TUNNEL_CSUM)) ||
 839             ((tpi->flags & TUNNEL_CSUM) &&
 840              !(tunnel->parms.i_flags & TUNNEL_CSUM))) {
 841                 tunnel->dev->stats.rx_crc_errors++;
 842                 tunnel->dev->stats.rx_errors++;
 843                 goto drop;
 844         }
 845
 846         if (tunnel->parms.i_flags & TUNNEL_SEQ) {
 847                 if (!(tpi->flags & TUNNEL_SEQ) ||
 848                     (tunnel->i_seqno &&
 849                      (s32)(ntohl(tpi->seq) - tunnel->i_seqno) < 0)) {
 850                         tunnel->dev->stats.rx_fifo_errors++;
 851                         tunnel->dev->stats.rx_errors++;
 852                         goto drop;
 853                 }
 854                 tunnel->i_seqno = ntohl(tpi->seq) + 1;
 855         }
 856
 857         skb->protocol = tpi->proto;
 858
 859         /* Warning: All skb pointers will be invalidated! */
 860         if (tunnel->dev->type == ARPHRD_ETHER) {
 861                 if (!pskb_may_pull(skb, ETH_HLEN)) {
 862                         tunnel->dev->stats.rx_length_errors++;
 863                         tunnel->dev->stats.rx_errors++;
 864                         goto drop;
 865                 }
 866
 867                 ipv6h = ipv6_hdr(skb);
 868                 skb->protocol = eth_type_trans(skb, tunnel->dev);
 869                 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);
 870         } else {
 871                 skb->dev = tunnel->dev;
 872         }
 873
 874         skb_reset_network_header(skb);
 875         memset(skb->cb, 0, sizeof(struct inet6_skb_parm));
 876
 877         __skb_tunnel_rx(skb, tunnel->dev, tunnel->net);
 878
 879         err = dscp_ecn_decapsulate(tunnel, ipv6h, skb);
 880         if (unlikely(err)) {
 881                 if (log_ecn_err)
 882                         net_info_ratelimited("non-ECT from %pI6 with DS=%#x\n",
 883                                              &ipv6h->saddr,
 884                                              ipv6_get_dsfield(ipv6h));
 885                 if (err > 1) {
 886                         ++tunnel->dev->stats.rx_frame_errors;
 887                         ++tunnel->dev->stats.rx_errors;
 888                         goto drop;
 889                 }
 890         }
 891
 892         tstats = this_cpu_ptr(tunnel->dev->tstats);
 893         u64_stats_update_begin(&tstats->syncp);
 894         tstats->rx_packets++;
 895         tstats->rx_bytes += skb->len;
 896         u64_stats_update_end(&tstats->syncp);
 897
 898         skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(tunnel->dev)));
 899
 900         if (tun_dst)
 901                 skb_dst_set(skb, (struct dst_entry *)tun_dst);
 902
 903         gro_cells_receive(&tunnel->gro_cells, skb);
 904         return 0;
 905
 906 drop:
 907         if (tun_dst)
 908                 dst_release((struct dst_entry *)tun_dst);
 909         kfree_skb(skb);
 910         return 0;
 911 }
 912
 913 int ip6_tnl_rcv(struct ip6_tnl *t, struct sk_buff *skb,
 914                 const struct tnl_ptk_info *tpi,
 915                 struct metadata_dst *tun_dst,
 916                 bool log_ecn_err)
 917 {
 918         return __ip6_tnl_rcv(t, skb, tpi, tun_dst, ip6ip6_dscp_ecn_decapsulate,
 919                              log_ecn_err);
 920 }
 921 EXPORT_SYMBOL(ip6_tnl_rcv);
 922
 923 static const struct tnl_ptk_info tpi_v6 = {
 924         /* no tunnel info required for ipxip6. */
 925         .proto = htons(ETH_P_IPV6),
 926 };
 927
 928 static const struct tnl_ptk_info tpi_v4 = {
 929         /* no tunnel info required for ipxip6. */
 930         .proto = htons(ETH_P_IP),
 931 };
 932
 933 static const struct tnl_ptk_info tpi_mpls = {
 934         /* no tunnel info required for mplsip6. */
 935         .proto = htons(ETH_P_MPLS_UC),
 936 };
 937
 938 static int ipxip6_rcv(struct sk_buff *skb, u8 ipproto,
 939                       const struct tnl_ptk_info *tpi,
 940                       int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t,
 941                                                   const struct ipv6hdr *ipv6h,
 942                                                   struct sk_buff *skb))
 943 {
 944         struct ip6_tnl *t;
 945         const struct ipv6hdr *ipv6h = ipv6_hdr(skb);
 946         struct metadata_dst *tun_dst = NULL;
 947         int ret = -1;
 948
 949         rcu_read_lock();
 950         t = ip6_tnl_lookup(dev_net(skb->dev), skb->dev->ifindex, &ipv6h->saddr, &ipv6h->daddr);
 951
 952         if (t) {
 953                 u8 tproto = READ_ONCE(t->parms.proto);
 954
 955                 if (tproto != ipproto && tproto != 0)
 956                         goto drop;
 957                 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
 958                         goto drop;
 959                 ipv6h = ipv6_hdr(skb);
 960                 if (!ip6_tnl_rcv_ctl(t, &ipv6h->daddr, &ipv6h->saddr))
 961                         goto drop;
 962                 if (iptunnel_pull_header(skb, 0, tpi->proto, false))
 963                         goto drop;
 964                 if (t->parms.collect_md) {
 965                         tun_dst = ipv6_tun_rx_dst(skb, 0, 0, 0);
 966                         if (!tun_dst)
 967                                 goto drop;
 968                 }
 969                 ret = __ip6_tnl_rcv(t, skb, tpi, tun_dst, dscp_ecn_decapsulate,
 970                                     log_ecn_error);
 971         }
 972
 973         rcu_read_unlock();
 974
 975         return ret;
 976
 977 drop:
 978         rcu_read_unlock();
 979         kfree_skb(skb);
 980         return 0;
 981 }
 982
 983 static int ip4ip6_rcv(struct sk_buff *skb)
 984 {
 985         return ipxip6_rcv(skb, IPPROTO_IPIP, &tpi_v4,
 986                           ip4ip6_dscp_ecn_decapsulate);
 987 }
 988
 989 static int ip6ip6_rcv(struct sk_buff *skb)
 990 {
 991         return ipxip6_rcv(skb, IPPROTO_IPV6, &tpi_v6,
 992                           ip6ip6_dscp_ecn_decapsulate);
 993 }
 994
 995 static int mplsip6_rcv(struct sk_buff *skb)
 996 {
 997         return ipxip6_rcv(skb, IPPROTO_MPLS, &tpi_mpls,
 998                           mplsip6_dscp_ecn_decapsulate);
 999 }
1000
1001 struct ipv6_tel_txoption {
1002         struct ipv6_txoptions ops;
1003         __u8 dst_opt[8];
1004 };
1005
1006 static void init_tel_txopt(struct ipv6_tel_txoption *opt, __u8 encap_limit)
1007 {
1008         memset(opt, 0, sizeof(struct ipv6_tel_txoption));
1009
1010         opt->dst_opt[2] = IPV6_TLV_TNL_ENCAP_LIMIT;
1011         opt->dst_opt[3] = 1;
1012         opt->dst_opt[4] = encap_limit;
1013         opt->dst_opt[5] = IPV6_TLV_PADN;
1014         opt->dst_opt[6] = 1;
1015
1016         opt->ops.dst1opt = (struct ipv6_opt_hdr *) opt->dst_opt;
1017         opt->ops.opt_nflen = 8;
1018 }
1019
1020 /**
1021  * ip6_tnl_addr_conflict - compare packet addresses to tunnel's own
1022  *   @t: the outgoing tunnel device
1023  *   @hdr: IPv6 header from the incoming packet
1024  *
1025  * Description:
1026  *   Avoid trivial tunneling loop by checking that tunnel exit-point
1027  *   doesn't match source of incoming packet.
1028  *
1029  * Return:
1030  *   1 if conflict,
1031  *   0 else
1032  **/
1033
1034 static inline bool
1035 ip6_tnl_addr_conflict(const struct ip6_tnl *t, const struct ipv6hdr *hdr)
1036 {
1037         return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr);
1038 }
1039
1040 int ip6_tnl_xmit_ctl(struct ip6_tnl *t,
1041                      const struct in6_addr *laddr,
1042                      const struct in6_addr *raddr)
1043 {
1044         struct __ip6_tnl_parm *p = &t->parms;
1045         int ret = 0;
1046         struct net *net = t->net;
1047
1048         if (t->parms.collect_md)
1049                 return 1;
1050
1051         if ((p->flags & IP6_TNL_F_CAP_XMIT) ||
1052             ((p->flags & IP6_TNL_F_CAP_PER_PACKET) &&
1053              (ip6_tnl_get_cap(t, laddr, raddr) & IP6_TNL_F_CAP_XMIT))) {
1054                 struct net_device *ldev = NULL;
1055
1056                 rcu_read_lock();
1057                 if (p->link)
1058                         ldev = dev_get_by_index_rcu(net, p->link);
1059
1060                 if (unlikely(!ipv6_chk_addr_and_flags(net, laddr, ldev, false,
1061                                                       0, IFA_F_TENTATIVE)))
1062                         pr_warn("%s xmit: Local address not yet configured!\n",
1063                                 p->name);
1064                 else if (!(p->flags & IP6_TNL_F_ALLOW_LOCAL_REMOTE) &&
1065                          !ipv6_addr_is_multicast(raddr) &&
1066                          unlikely(ipv6_chk_addr_and_flags(net, raddr, ldev,
1067                                                           true, 0, IFA_F_TENTATIVE)))
1068                         pr_warn("%s xmit: Routing loop! Remote address found on this node!\n",
1069                                 p->name);
1070                 else
1071                         ret = 1;
1072                 rcu_read_unlock();
1073         }
1074         return ret;
1075 }
1076 EXPORT_SYMBOL_GPL(ip6_tnl_xmit_ctl);
1077
1078 /**
1079  * ip6_tnl_xmit - encapsulate packet and send
1080  *   @skb: the outgoing socket buffer
1081  *   @dev: the outgoing tunnel device
1082  *   @dsfield: dscp code for outer header
1083  *   @fl6: flow of tunneled packet
1084  *   @encap_limit: encapsulation limit
1085  *   @pmtu: Path MTU is stored if packet is too big
1086  *   @proto: next header value
1087  *
1088  * Description:
1089  *   Build new header and do some sanity checks on the packet before sending
1090  *   it.
1091  *
1092  * Return:
1093  *   0 on success
1094  *   -1 fail
1095  *   %-EMSGSIZE message too big. return mtu in this case.
1096  **/
1097
1098 int ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev, __u8 dsfield,
1099                  struct flowi6 *fl6, int encap_limit, __u32 *pmtu,
1100                  __u8 proto)
1101 {
1102         struct ip6_tnl *t = netdev_priv(dev);
1103         struct net *net = t->net;
1104         struct net_device_stats *stats = &t->dev->stats;
1105         struct ipv6hdr *ipv6h;
1106         struct ipv6_tel_txoption opt;
1107         struct dst_entry *dst = NULL, *ndst = NULL;
1108         struct net_device *tdev;
1109         int mtu;
1110         unsigned int eth_hlen = t->dev->type == ARPHRD_ETHER ? ETH_HLEN : 0;
1111         unsigned int psh_hlen = sizeof(struct ipv6hdr) + t->encap_hlen;
1112         unsigned int max_headroom = psh_hlen;
1113         bool use_cache = false;
1114         u8 hop_limit;
1115         int err = -1;
1116
1117         if (t->parms.collect_md) {
1118                 hop_limit = skb_tunnel_info(skb)->key.ttl;
1119                 goto route_lookup;
1120         } else {
1121                 hop_limit = t->parms.hop_limit;
1122         }
1123
1124         /* NBMA tunnel */
1125         if (ipv6_addr_any(&t->parms.raddr)) {
1126                 if (skb->protocol == htons(ETH_P_IPV6)) {
1127                         struct in6_addr *addr6;
1128                         struct neighbour *neigh;
1129                         int addr_type;
1130
1131                         if (!skb_dst(skb))
1132                                 goto tx_err_link_failure;
1133
1134                         neigh = dst_neigh_lookup(skb_dst(skb),
1135                                                  &ipv6_hdr(skb)->daddr);
1136                         if (!neigh)
1137                                 goto tx_err_link_failure;
1138
1139                         addr6 = (struct in6_addr *)&neigh->primary_key;
1140                         addr_type = ipv6_addr_type(addr6);
1141
1142                         if (addr_type == IPV6_ADDR_ANY)
1143                                 addr6 = &ipv6_hdr(skb)->daddr;
1144
1145                         memcpy(&fl6->daddr, addr6, sizeof(fl6->daddr));
1146                         neigh_release(neigh);
1147                 }
1148         } else if (t->parms.proto != 0 && !(t->parms.flags &
1149                                             (IP6_TNL_F_USE_ORIG_TCLASS |
1150                                              IP6_TNL_F_USE_ORIG_FWMARK))) {
1151                 /* enable the cache only if neither the outer protocol nor the
1152                  * routing decision depends on the current inner header value
1153                  */
1154                 use_cache = true;
1155         }
1156
1157         if (use_cache)
1158                 dst = dst_cache_get(&t->dst_cache);
1159
1160         if (!ip6_tnl_xmit_ctl(t, &fl6->saddr, &fl6->daddr))
1161                 goto tx_err_link_failure;
1162
1163         if (!dst) {
1164 route_lookup:
1165                 /* add dsfield to flowlabel for route lookup */
1166                 fl6->flowlabel = ip6_make_flowinfo(dsfield, fl6->flowlabel);
1167
1168                 dst = ip6_route_output(net, NULL, fl6);
1169
1170                 if (dst->error)
1171                         goto tx_err_link_failure;
1172                 dst = xfrm_lookup(net, dst, flowi6_to_flowi(fl6), NULL, 0);
1173                 if (IS_ERR(dst)) {
1174                         err = PTR_ERR(dst);
1175                         dst = NULL;
1176                         goto tx_err_link_failure;
1177                 }
1178                 if (t->parms.collect_md && ipv6_addr_any(&fl6->saddr) &&
1179                     ipv6_dev_get_saddr(net, ip6_dst_idev(dst)->dev,
1180                                        &fl6->daddr, 0, &fl6->saddr))
1181                         goto tx_err_link_failure;
1182                 ndst = dst;
1183         }
1184
1185         tdev = dst->dev;
1186
1187         if (tdev == dev) {
1188                 stats->collisions++;
1189                 net_warn_ratelimited("%s: Local routing loop detected!\n",
1190                                      t->parms.name);
1191                 goto tx_err_dst_release;
1192         }
1193         mtu = dst_mtu(dst) - eth_hlen - psh_hlen - t->tun_hlen;
1194         if (encap_limit >= 0) {
1195                 max_headroom += 8;
1196                 mtu -= 8;
1197         }
1198         mtu = max(mtu, skb->protocol == htons(ETH_P_IPV6) ?
1199                        IPV6_MIN_MTU : IPV4_MIN_MTU);
1200
1201         skb_dst_update_pmtu_no_confirm(skb, mtu);
1202         if (skb->len - t->tun_hlen - eth_hlen > mtu && !skb_is_gso(skb)) {
1203                 *pmtu = mtu;
1204                 err = -EMSGSIZE;
1205                 goto tx_err_dst_release;
1206         }
1207
1208         if (t->err_count > 0) {
1209                 if (time_before(jiffies,
1210                                 t->err_time + IP6TUNNEL_ERR_TIMEO)) {
1211                         t->err_count--;
1212
1213                         dst_link_failure(skb);
1214                 } else {
1215                         t->err_count = 0;
1216                 }
1217         }
1218
1219         skb_scrub_packet(skb, !net_eq(t->net, dev_net(dev)));
1220
1221         /*
1222          * Okay, now see if we can stuff it in the buffer as-is.
1223          */
1224         max_headroom += LL_RESERVED_SPACE(tdev);
1225
1226         if (skb_headroom(skb) < max_headroom || skb_shared(skb) ||
1227             (skb_cloned(skb) && !skb_clone_writable(skb, 0))) {
1228                 struct sk_buff *new_skb;
1229
1230                 new_skb = skb_realloc_headroom(skb, max_headroom);
1231                 if (!new_skb)
1232                         goto tx_err_dst_release;
1233
1234                 if (skb->sk)
1235                         skb_set_owner_w(new_skb, skb->sk);
1236                 consume_skb(skb);
1237                 skb = new_skb;
1238         }
1239
1240         if (t->parms.collect_md) {
1241                 if (t->encap.type != TUNNEL_ENCAP_NONE)
1242                         goto tx_err_dst_release;
1243         } else {
1244                 if (use_cache && ndst)
1245                         dst_cache_set_ip6(&t->dst_cache, ndst, &fl6->saddr);
1246         }
1247         skb_dst_set(skb, dst);
1248
1249         if (hop_limit == 0) {
1250                 if (skb->protocol == htons(ETH_P_IP))
1251                         hop_limit = ip_hdr(skb)->ttl;
1252                 else if (skb->protocol == htons(ETH_P_IPV6))
1253                         hop_limit = ipv6_hdr(skb)->hop_limit;
1254                 else
1255                         hop_limit = ip6_dst_hoplimit(dst);
1256         }
1257
1258         /* Calculate max headroom for all the headers and adjust
1259          * needed_headroom if necessary.
1260          */
1261         max_headroom = LL_RESERVED_SPACE(dst->dev) + sizeof(struct ipv6hdr)
1262                         + dst->header_len + t->hlen;
1263         if (max_headroom > dev->needed_headroom)
1264                 dev->needed_headroom = max_headroom;
1265
1266         err = ip6_tnl_encap(skb, t, &proto, fl6);
1267         if (err)
1268                 return err;
1269
1270         if (encap_limit >= 0) {
1271                 init_tel_txopt(&opt, encap_limit);
1272                 ipv6_push_frag_opts(skb, &opt.ops, &proto);
1273         }
1274
1275         skb_set_inner_ipproto(skb, proto);
1276
1277         skb_push(skb, sizeof(struct ipv6hdr));
1278         skb_reset_network_header(skb);
1279         ipv6h = ipv6_hdr(skb);
1280         ip6_flow_hdr(ipv6h, dsfield,
1281                      ip6_make_flowlabel(net, skb, fl6->flowlabel, true, fl6));
1282         ipv6h->hop_limit = hop_limit;
1283         ipv6h->nexthdr = proto;
1284         ipv6h->saddr = fl6->saddr;
1285         ipv6h->daddr = fl6->daddr;
1286         ip6tunnel_xmit(NULL, skb, dev);
1287         return 0;
1288 tx_err_link_failure:
1289         stats->tx_carrier_errors++;
1290         dst_link_failure(skb);
1291 tx_err_dst_release:
1292         dst_release(dst);
1293         return err;
1294 }
1295 EXPORT_SYMBOL(ip6_tnl_xmit);
1296
1297 static inline int
1298 ipxip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev,
1299                 u8 protocol)
1300 {
1301         struct ip6_tnl *t = netdev_priv(dev);
1302         struct ipv6hdr *ipv6h;
1303         const struct iphdr  *iph;
1304         int encap_limit = -1;
1305         __u16 offset;
1306         struct flowi6 fl6;
1307         __u8 dsfield, orig_dsfield;
1308         __u32 mtu;
1309         u8 tproto;
1310         int err;
1311
1312         tproto = READ_ONCE(t->parms.proto);
1313         if (tproto != protocol && tproto != 0)
1314                 return -1;
1315
1316         if (t->parms.collect_md) {
1317                 struct ip_tunnel_info *tun_info;
1318                 const struct ip_tunnel_key *key;
1319
1320                 tun_info = skb_tunnel_info(skb);
1321                 if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) ||
1322                              ip_tunnel_info_af(tun_info) != AF_INET6))
1323                         return -1;
1324                 key = &tun_info->key;
1325                 memset(&fl6, 0, sizeof(fl6));
1326                 fl6.flowi6_proto = protocol;
1327                 fl6.saddr = key->u.ipv6.src;
1328                 fl6.daddr = key->u.ipv6.dst;
1329                 fl6.flowlabel = key->label;
1330                 dsfield =  key->tos;
1331                 switch (protocol) {
1332                 case IPPROTO_IPIP:
1333                         iph = ip_hdr(skb);
1334                         orig_dsfield = ipv4_get_dsfield(iph);
1335                         break;
1336                 case IPPROTO_IPV6:
1337                         ipv6h = ipv6_hdr(skb);
1338                         orig_dsfield = ipv6_get_dsfield(ipv6h);
1339                         break;
1340                 default:
1341                         orig_dsfield = dsfield;
1342                         break;
1343                 }
1344         } else {
1345                 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1346                         encap_limit = t->parms.encap_limit;
1347                 if (protocol == IPPROTO_IPV6) {
1348                         offset = ip6_tnl_parse_tlv_enc_lim(skb,
1349                                                 skb_network_header(skb));
1350                         /* ip6_tnl_parse_tlv_enc_lim() might have
1351                          * reallocated skb->head
1352                          */
1353                         if (offset > 0) {
1354                                 struct ipv6_tlv_tnl_enc_lim *tel;
1355
1356                                 tel = (void *)&skb_network_header(skb)[offset];
1357                                 if (tel->encap_limit == 0) {
1358                                         icmpv6_send(skb, ICMPV6_PARAMPROB,
1359                                                 ICMPV6_HDR_FIELD, offset + 2);
1360                                         return -1;
1361                                 }
1362                                 encap_limit = tel->encap_limit - 1;
1363                         }
1364                 }
1365
1366                 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
1367                 fl6.flowi6_proto = protocol;
1368
1369                 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
1370                         fl6.flowi6_mark = skb->mark;
1371                 else
1372                         fl6.flowi6_mark = t->parms.fwmark;
1373                 switch (protocol) {
1374                 case IPPROTO_IPIP:
1375                         iph = ip_hdr(skb);
1376                         orig_dsfield = ipv4_get_dsfield(iph);
1377                         if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
1378                                 dsfield = orig_dsfield;
1379                         else
1380                                 dsfield = ip6_tclass(t->parms.flowinfo);
1381                         break;
1382                 case IPPROTO_IPV6:
1383                         ipv6h = ipv6_hdr(skb);
1384                         orig_dsfield = ipv6_get_dsfield(ipv6h);
1385                         if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
1386                                 dsfield = orig_dsfield;
1387                         else
1388                                 dsfield = ip6_tclass(t->parms.flowinfo);
1389                         if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL)
1390                                 fl6.flowlabel |= ip6_flowlabel(ipv6h);
1391                         break;
1392                 default:
1393                         orig_dsfield = dsfield = ip6_tclass(t->parms.flowinfo);
1394                         break;
1395                 }
1396         }
1397
1398         fl6.flowi6_uid = sock_net_uid(dev_net(dev), NULL);
1399         dsfield = INET_ECN_encapsulate(dsfield, orig_dsfield);
1400
1401         if (iptunnel_handle_offloads(skb, SKB_GSO_IPXIP6))
1402                 return -1;
1403
1404         err = ip6_tnl_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu,
1405                            protocol);
1406         if (err != 0) {
1407                 /* XXX: send ICMP error even if DF is not set. */
1408                 if (err == -EMSGSIZE)
1409                         switch (protocol) {
1410                         case IPPROTO_IPIP:
1411                                 icmp_send(skb, ICMP_DEST_UNREACH,
1412                                           ICMP_FRAG_NEEDED, htonl(mtu));
1413                                 break;
1414                         case IPPROTO_IPV6:
1415                                 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
1416                                 break;
1417                         default:
1418                                 break;
1419                         }
1420                 return -1;
1421         }
1422
1423         return 0;
1424 }
1425
1426 static netdev_tx_t
1427 ip6_tnl_start_xmit(struct sk_buff *skb, struct net_device *dev)
1428 {
1429         struct ip6_tnl *t = netdev_priv(dev);
1430         struct net_device_stats *stats = &t->dev->stats;
1431         u8 ipproto;
1432         int ret;
1433
1434         if (!pskb_inet_may_pull(skb))
1435                 goto tx_err;
1436
1437         switch (skb->protocol) {
1438         case htons(ETH_P_IP):
1439                 ipproto = IPPROTO_IPIP;
1440                 break;
1441         case htons(ETH_P_IPV6):
1442                 if (ip6_tnl_addr_conflict(t, ipv6_hdr(skb)))
1443                         goto tx_err;
1444                 ipproto = IPPROTO_IPV6;
1445                 break;
1446         case htons(ETH_P_MPLS_UC):
1447                 ipproto = IPPROTO_MPLS;
1448                 break;
1449         default:
1450                 goto tx_err;
1451         }
1452
1453         ret = ipxip6_tnl_xmit(skb, dev, ipproto);
1454         if (ret < 0)
1455                 goto tx_err;
1456
1457         return NETDEV_TX_OK;
1458
1459 tx_err:
1460         stats->tx_errors++;
1461         stats->tx_dropped++;
1462         kfree_skb(skb);
1463         return NETDEV_TX_OK;
1464 }
1465
1466 static void ip6_tnl_link_config(struct ip6_tnl *t)
1467 {
1468         struct net_device *dev = t->dev;
1469         struct net_device *tdev = NULL;
1470         struct __ip6_tnl_parm *p = &t->parms;
1471         struct flowi6 *fl6 = &t->fl.u.ip6;
1472         unsigned int mtu;
1473         int t_hlen;
1474
1475         memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr));
1476         memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr));
1477
1478         /* Set up flowi template */
1479         fl6->saddr = p->laddr;
1480         fl6->daddr = p->raddr;
1481         fl6->flowi6_oif = p->link;
1482         fl6->flowlabel = 0;
1483
1484         if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS))
1485                 fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo;
1486         if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL))
1487                 fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo;
1488
1489         p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET);
1490         p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr);
1491
1492         if (p->flags&IP6_TNL_F_CAP_XMIT && p->flags&IP6_TNL_F_CAP_RCV)
1493                 dev->flags |= IFF_POINTOPOINT;
1494         else
1495                 dev->flags &= ~IFF_POINTOPOINT;
1496
1497         t->tun_hlen = 0;
1498         t->hlen = t->encap_hlen + t->tun_hlen;
1499         t_hlen = t->hlen + sizeof(struct ipv6hdr);
1500
1501         if (p->flags & IP6_TNL_F_CAP_XMIT) {
1502                 int strict = (ipv6_addr_type(&p->raddr) &
1503                               (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL));
1504
1505                 struct rt6_info *rt = rt6_lookup(t->net,
1506                                                  &p->raddr, &p->laddr,
1507                                                  p->link, NULL, strict);
1508                 if (rt) {
1509                         tdev = rt->dst.dev;
1510                         ip6_rt_put(rt);
1511                 }
1512
1513                 if (!tdev && p->link)
1514                         tdev = __dev_get_by_index(t->net, p->link);
1515
1516                 if (tdev) {
1517                         dev->hard_header_len = tdev->hard_header_len + t_hlen;
1518                         mtu = min_t(unsigned int, tdev->mtu, IP6_MAX_MTU);
1519
1520                         dev->mtu = mtu - t_hlen;
1521                         if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1522                                 dev->mtu -= 8;
1523
1524                         if (dev->mtu < IPV6_MIN_MTU)
1525                                 dev->mtu = IPV6_MIN_MTU;
1526                 }
1527         }
1528 }
1529
1530 /**
1531  * ip6_tnl_change - update the tunnel parameters
1532  *   @t: tunnel to be changed
1533  *   @p: tunnel configuration parameters
1534  *
1535  * Description:
1536  *   ip6_tnl_change() updates the tunnel parameters
1537  **/
1538
1539 static int
1540 ip6_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p)
1541 {
1542         t->parms.laddr = p->laddr;
1543         t->parms.raddr = p->raddr;
1544         t->parms.flags = p->flags;
1545         t->parms.hop_limit = p->hop_limit;
1546         t->parms.encap_limit = p->encap_limit;
1547         t->parms.flowinfo = p->flowinfo;
1548         t->parms.link = p->link;
1549         t->parms.proto = p->proto;
1550         t->parms.fwmark = p->fwmark;
1551         dst_cache_reset(&t->dst_cache);
1552         ip6_tnl_link_config(t);
1553         return 0;
1554 }
1555
1556 static int ip6_tnl_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p)
1557 {
1558         struct net *net = t->net;
1559         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1560         int err;
1561
1562         ip6_tnl_unlink(ip6n, t);
1563         synchronize_net();
1564         err = ip6_tnl_change(t, p);
1565         ip6_tnl_link(ip6n, t);
1566         netdev_state_change(t->dev);
1567         return err;
1568 }
1569
1570 static int ip6_tnl0_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p)
1571 {
1572         /* for default tnl0 device allow to change only the proto */
1573         t->parms.proto = p->proto;
1574         netdev_state_change(t->dev);
1575         return 0;
1576 }
1577
1578 static void
1579 ip6_tnl_parm_from_user(struct __ip6_tnl_parm *p, const struct ip6_tnl_parm *u)
1580 {
1581         p->laddr = u->laddr;
1582         p->raddr = u->raddr;
1583         p->flags = u->flags;
1584         p->hop_limit = u->hop_limit;
1585         p->encap_limit = u->encap_limit;
1586         p->flowinfo = u->flowinfo;
1587         p->link = u->link;
1588         p->proto = u->proto;
1589         memcpy(p->name, u->name, sizeof(u->name));
1590 }
1591
1592 static void
1593 ip6_tnl_parm_to_user(struct ip6_tnl_parm *u, const struct __ip6_tnl_parm *p)
1594 {
1595         u->laddr = p->laddr;
1596         u->raddr = p->raddr;
1597         u->flags = p->flags;
1598         u->hop_limit = p->hop_limit;
1599         u->encap_limit = p->encap_limit;
1600         u->flowinfo = p->flowinfo;
1601         u->link = p->link;
1602         u->proto = p->proto;
1603         memcpy(u->name, p->name, sizeof(u->name));
1604 }
1605
1606 /**
1607  * ip6_tnl_ioctl - configure ipv6 tunnels from userspace
1608  *   @dev: virtual device associated with tunnel
1609  *   @ifr: parameters passed from userspace
1610  *   @cmd: command to be performed
1611  *
1612  * Description:
1613  *   ip6_tnl_ioctl() is used for managing IPv6 tunnels
1614  *   from userspace.
1615  *
1616  *   The possible commands are the following:
1617  *     %SIOCGETTUNNEL: get tunnel parameters for device
1618  *     %SIOCADDTUNNEL: add tunnel matching given tunnel parameters
1619  *     %SIOCCHGTUNNEL: change tunnel parameters to those given
1620  *     %SIOCDELTUNNEL: delete tunnel
1621  *
1622  *   The fallback device "ip6tnl0", created during module
1623  *   initialization, can be used for creating other tunnel devices.
1624  *
1625  * Return:
1626  *   0 on success,
1627  *   %-EFAULT if unable to copy data to or from userspace,
1628  *   %-EPERM if current process hasn't %CAP_NET_ADMIN set
1629  *   %-EINVAL if passed tunnel parameters are invalid,
1630  *   %-EEXIST if changing a tunnel's parameters would cause a conflict
1631  *   %-ENODEV if attempting to change or delete a nonexisting device
1632  **/
1633
1634 static int
1635 ip6_tnl_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
1636 {
1637         int err = 0;
1638         struct ip6_tnl_parm p;
1639         struct __ip6_tnl_parm p1;
1640         struct ip6_tnl *t = netdev_priv(dev);
1641         struct net *net = t->net;
1642         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1643
1644         memset(&p1, 0, sizeof(p1));
1645
1646         switch (cmd) {
1647         case SIOCGETTUNNEL:
1648                 if (dev == ip6n->fb_tnl_dev) {
1649                         if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
1650                                 err = -EFAULT;
1651                                 break;
1652                         }
1653                         ip6_tnl_parm_from_user(&p1, &p);
1654                         t = ip6_tnl_locate(net, &p1, 0);
1655                         if (IS_ERR(t))
1656                                 t = netdev_priv(dev);
1657                 } else {
1658                         memset(&p, 0, sizeof(p));
1659                 }
1660                 ip6_tnl_parm_to_user(&p, &t->parms);
1661                 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) {
1662                         err = -EFAULT;
1663                 }
1664                 break;
1665         case SIOCADDTUNNEL:
1666         case SIOCCHGTUNNEL:
1667                 err = -EPERM;
1668                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1669                         break;
1670                 err = -EFAULT;
1671                 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
1672                         break;
1673                 err = -EINVAL;
1674                 if (p.proto != IPPROTO_IPV6 && p.proto != IPPROTO_IPIP &&
1675                     p.proto != 0)
1676                         break;
1677                 ip6_tnl_parm_from_user(&p1, &p);
1678                 t = ip6_tnl_locate(net, &p1, cmd == SIOCADDTUNNEL);
1679                 if (cmd == SIOCCHGTUNNEL) {
1680                         if (!IS_ERR(t)) {
1681                                 if (t->dev != dev) {
1682                                         err = -EEXIST;
1683                                         break;
1684                                 }
1685                         } else
1686                                 t = netdev_priv(dev);
1687                         if (dev == ip6n->fb_tnl_dev)
1688                                 err = ip6_tnl0_update(t, &p1);
1689                         else
1690                                 err = ip6_tnl_update(t, &p1);
1691                 }
1692                 if (!IS_ERR(t)) {
1693                         err = 0;
1694                         ip6_tnl_parm_to_user(&p, &t->parms);
1695                         if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
1696                                 err = -EFAULT;
1697
1698                 } else {
1699                         err = PTR_ERR(t);
1700                 }
1701                 break;
1702         case SIOCDELTUNNEL:
1703                 err = -EPERM;
1704                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1705                         break;
1706
1707                 if (dev == ip6n->fb_tnl_dev) {
1708                         err = -EFAULT;
1709                         if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
1710                                 break;
1711                         err = -ENOENT;
1712                         ip6_tnl_parm_from_user(&p1, &p);
1713                         t = ip6_tnl_locate(net, &p1, 0);
1714                         if (IS_ERR(t))
1715                                 break;
1716                         err = -EPERM;
1717                         if (t->dev == ip6n->fb_tnl_dev)
1718                                 break;
1719                         dev = t->dev;
1720                 }
1721                 err = 0;
1722                 unregister_netdevice(dev);
1723                 break;
1724         default:
1725                 err = -EINVAL;
1726         }
1727         return err;
1728 }
1729
1730 /**
1731  * ip6_tnl_change_mtu - change mtu manually for tunnel device
1732  *   @dev: virtual device associated with tunnel
1733  *   @new_mtu: the new mtu
1734  *
1735  * Return:
1736  *   0 on success,
1737  *   %-EINVAL if mtu too small
1738  **/
1739
1740 int ip6_tnl_change_mtu(struct net_device *dev, int new_mtu)
1741 {
1742         struct ip6_tnl *tnl = netdev_priv(dev);
1743
1744         if (tnl->parms.proto == IPPROTO_IPV6) {
1745                 if (new_mtu < IPV6_MIN_MTU)
1746                         return -EINVAL;
1747         } else {
1748                 if (new_mtu < ETH_MIN_MTU)
1749                         return -EINVAL;
1750         }
1751         if (tnl->parms.proto == IPPROTO_IPV6 || tnl->parms.proto == 0) {
1752                 if (new_mtu > IP6_MAX_MTU - dev->hard_header_len)
1753                         return -EINVAL;
1754         } else {
1755                 if (new_mtu > IP_MAX_MTU - dev->hard_header_len)
1756                         return -EINVAL;
1757         }
1758         dev->mtu = new_mtu;
1759         return 0;
1760 }
1761 EXPORT_SYMBOL(ip6_tnl_change_mtu);
1762
1763 int ip6_tnl_get_iflink(const struct net_device *dev)
1764 {
1765         struct ip6_tnl *t = netdev_priv(dev);
1766
1767         return t->parms.link;
1768 }
1769 EXPORT_SYMBOL(ip6_tnl_get_iflink);
1770
1771 int ip6_tnl_encap_add_ops(const struct ip6_tnl_encap_ops *ops,
1772                           unsigned int num)
1773 {
1774         if (num >= MAX_IPTUN_ENCAP_OPS)
1775                 return -ERANGE;
1776
1777         return !cmpxchg((const struct ip6_tnl_encap_ops **)
1778                         &ip6tun_encaps[num],
1779                         NULL, ops) ? 0 : -1;
1780 }
1781 EXPORT_SYMBOL(ip6_tnl_encap_add_ops);
1782
1783 int ip6_tnl_encap_del_ops(const struct ip6_tnl_encap_ops *ops,
1784                           unsigned int num)
1785 {
1786         int ret;
1787
1788         if (num >= MAX_IPTUN_ENCAP_OPS)
1789                 return -ERANGE;
1790
1791         ret = (cmpxchg((const struct ip6_tnl_encap_ops **)
1792                        &ip6tun_encaps[num],
1793                        ops, NULL) == ops) ? 0 : -1;
1794
1795         synchronize_net();
1796
1797         return ret;
1798 }
1799 EXPORT_SYMBOL(ip6_tnl_encap_del_ops);
1800
1801 int ip6_tnl_encap_setup(struct ip6_tnl *t,
1802                         struct ip_tunnel_encap *ipencap)
1803 {
1804         int hlen;
1805
1806         memset(&t->encap, 0, sizeof(t->encap));
1807
1808         hlen = ip6_encap_hlen(ipencap);
1809         if (hlen < 0)
1810                 return hlen;
1811
1812         t->encap.type = ipencap->type;
1813         t->encap.sport = ipencap->sport;
1814         t->encap.dport = ipencap->dport;
1815         t->encap.flags = ipencap->flags;
1816
1817         t->encap_hlen = hlen;
1818         t->hlen = t->encap_hlen + t->tun_hlen;
1819
1820         return 0;
1821 }
1822 EXPORT_SYMBOL_GPL(ip6_tnl_encap_setup);
1823
1824 static const struct net_device_ops ip6_tnl_netdev_ops = {
1825         .ndo_init       = ip6_tnl_dev_init,
1826         .ndo_uninit     = ip6_tnl_dev_uninit,
1827         .ndo_start_xmit = ip6_tnl_start_xmit,
1828         .ndo_do_ioctl   = ip6_tnl_ioctl,
1829         .ndo_change_mtu = ip6_tnl_change_mtu,
1830         .ndo_get_stats  = ip6_get_stats,
1831         .ndo_get_iflink = ip6_tnl_get_iflink,
1832 };
1833
1834 #define IPXIPX_FEATURES (NETIF_F_SG |           \
1835                          NETIF_F_FRAGLIST |     \
1836                          NETIF_F_HIGHDMA |      \
1837                          NETIF_F_GSO_SOFTWARE | \
1838                          NETIF_F_HW_CSUM)
1839
1840 /**
1841  * ip6_tnl_dev_setup - setup virtual tunnel device
1842  *   @dev: virtual device associated with tunnel
1843  *
1844  * Description:
1845  *   Initialize function pointers and device parameters
1846  **/
1847
1848 static void ip6_tnl_dev_setup(struct net_device *dev)
1849 {
1850         dev->netdev_ops = &ip6_tnl_netdev_ops;
1851         dev->header_ops = &ip_tunnel_header_ops;
1852         dev->needs_free_netdev = true;
1853         dev->priv_destructor = ip6_dev_free;
1854
1855         dev->type = ARPHRD_TUNNEL6;
1856         dev->flags |= IFF_NOARP;
1857         dev->addr_len = sizeof(struct in6_addr);
1858         dev->features |= NETIF_F_LLTX;
1859         netif_keep_dst(dev);
1860
1861         dev->features           |= IPXIPX_FEATURES;
1862         dev->hw_features        |= IPXIPX_FEATURES;
1863
1864         /* This perm addr will be used as interface identifier by IPv6 */
1865         dev->addr_assign_type = NET_ADDR_RANDOM;
1866         eth_random_addr(dev->perm_addr);
1867 }
1868
1869
1870 /**
1871  * ip6_tnl_dev_init_gen - general initializer for all tunnel devices
1872  *   @dev: virtual device associated with tunnel
1873  **/
1874
1875 static inline int
1876 ip6_tnl_dev_init_gen(struct net_device *dev)
1877 {
1878         struct ip6_tnl *t = netdev_priv(dev);
1879         int ret;
1880         int t_hlen;
1881
1882         t->dev = dev;
1883         t->net = dev_net(dev);
1884         dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1885         if (!dev->tstats)
1886                 return -ENOMEM;
1887
1888         ret = dst_cache_init(&t->dst_cache, GFP_KERNEL);
1889         if (ret)
1890                 goto free_stats;
1891
1892         ret = gro_cells_init(&t->gro_cells, dev);
1893         if (ret)
1894                 goto destroy_dst;
1895
1896         t->tun_hlen = 0;
1897         t->hlen = t->encap_hlen + t->tun_hlen;
1898         t_hlen = t->hlen + sizeof(struct ipv6hdr);
1899
1900         dev->type = ARPHRD_TUNNEL6;
1901         dev->hard_header_len = LL_MAX_HEADER + t_hlen;
1902         dev->mtu = ETH_DATA_LEN - t_hlen;
1903         if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1904                 dev->mtu -= 8;
1905         dev->min_mtu = ETH_MIN_MTU;
1906         dev->max_mtu = IP6_MAX_MTU - dev->hard_header_len;
1907
1908         return 0;
1909
1910 destroy_dst:
1911         dst_cache_destroy(&t->dst_cache);
1912 free_stats:
1913         free_percpu(dev->tstats);
1914         dev->tstats = NULL;
1915
1916         return ret;
1917 }
1918
1919 /**
1920  * ip6_tnl_dev_init - initializer for all non fallback tunnel devices
1921  *   @dev: virtual device associated with tunnel
1922  **/
1923
1924 static int ip6_tnl_dev_init(struct net_device *dev)
1925 {
1926         struct ip6_tnl *t = netdev_priv(dev);
1927         int err = ip6_tnl_dev_init_gen(dev);
1928
1929         if (err)
1930                 return err;
1931         ip6_tnl_link_config(t);
1932         if (t->parms.collect_md)
1933                 netif_keep_dst(dev);
1934         return 0;
1935 }
1936
1937 /**
1938  * ip6_fb_tnl_dev_init - initializer for fallback tunnel device
1939  *   @dev: fallback device
1940  *
1941  * Return: 0
1942  **/
1943
1944 static int __net_init ip6_fb_tnl_dev_init(struct net_device *dev)
1945 {
1946         struct ip6_tnl *t = netdev_priv(dev);
1947         struct net *net = dev_net(dev);
1948         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1949
1950         t->parms.proto = IPPROTO_IPV6;
1951         dev_hold(dev);
1952
1953         rcu_assign_pointer(ip6n->tnls_wc[0], t);
1954         return 0;
1955 }
1956
1957 static int ip6_tnl_validate(struct nlattr *tb[], struct nlattr *data[],
1958                             struct netlink_ext_ack *extack)
1959 {
1960         u8 proto;
1961
1962         if (!data || !data[IFLA_IPTUN_PROTO])
1963                 return 0;
1964
1965         proto = nla_get_u8(data[IFLA_IPTUN_PROTO]);
1966         if (proto != IPPROTO_IPV6 &&
1967             proto != IPPROTO_IPIP &&
1968             proto != 0)
1969                 return -EINVAL;
1970
1971         return 0;
1972 }
1973
1974 static void ip6_tnl_netlink_parms(struct nlattr *data[],
1975                                   struct __ip6_tnl_parm *parms)
1976 {
1977         memset(parms, 0, sizeof(*parms));
1978
1979         if (!data)
1980                 return;
1981
1982         if (data[IFLA_IPTUN_LINK])
1983                 parms->link = nla_get_u32(data[IFLA_IPTUN_LINK]);
1984
1985         if (data[IFLA_IPTUN_LOCAL])
1986                 parms->laddr = nla_get_in6_addr(data[IFLA_IPTUN_LOCAL]);
1987
1988         if (data[IFLA_IPTUN_REMOTE])
1989                 parms->raddr = nla_get_in6_addr(data[IFLA_IPTUN_REMOTE]);
1990
1991         if (data[IFLA_IPTUN_TTL])
1992                 parms->hop_limit = nla_get_u8(data[IFLA_IPTUN_TTL]);
1993
1994         if (data[IFLA_IPTUN_ENCAP_LIMIT])
1995                 parms->encap_limit = nla_get_u8(data[IFLA_IPTUN_ENCAP_LIMIT]);
1996
1997         if (data[IFLA_IPTUN_FLOWINFO])
1998                 parms->flowinfo = nla_get_be32(data[IFLA_IPTUN_FLOWINFO]);
1999
2000         if (data[IFLA_IPTUN_FLAGS])
2001                 parms->flags = nla_get_u32(data[IFLA_IPTUN_FLAGS]);
2002
2003         if (data[IFLA_IPTUN_PROTO])
2004                 parms->proto = nla_get_u8(data[IFLA_IPTUN_PROTO]);
2005
2006         if (data[IFLA_IPTUN_COLLECT_METADATA])
2007                 parms->collect_md = true;
2008
2009         if (data[IFLA_IPTUN_FWMARK])
2010                 parms->fwmark = nla_get_u32(data[IFLA_IPTUN_FWMARK]);
2011 }
2012
2013 static bool ip6_tnl_netlink_encap_parms(struct nlattr *data[],
2014                                         struct ip_tunnel_encap *ipencap)
2015 {
2016         bool ret = false;
2017
2018         memset(ipencap, 0, sizeof(*ipencap));
2019
2020         if (!data)
2021                 return ret;
2022
2023         if (data[IFLA_IPTUN_ENCAP_TYPE]) {
2024                 ret = true;
2025                 ipencap->type = nla_get_u16(data[IFLA_IPTUN_ENCAP_TYPE]);
2026         }
2027
2028         if (data[IFLA_IPTUN_ENCAP_FLAGS]) {
2029                 ret = true;
2030                 ipencap->flags = nla_get_u16(data[IFLA_IPTUN_ENCAP_FLAGS]);
2031         }
2032
2033         if (data[IFLA_IPTUN_ENCAP_SPORT]) {
2034                 ret = true;
2035                 ipencap->sport = nla_get_be16(data[IFLA_IPTUN_ENCAP_SPORT]);
2036         }
2037
2038         if (data[IFLA_IPTUN_ENCAP_DPORT]) {
2039                 ret = true;
2040                 ipencap->dport = nla_get_be16(data[IFLA_IPTUN_ENCAP_DPORT]);
2041         }
2042
2043         return ret;
2044 }
2045
2046 static int ip6_tnl_newlink(struct net *src_net, struct net_device *dev,
2047                            struct nlattr *tb[], struct nlattr *data[],
2048                            struct netlink_ext_ack *extack)
2049 {
2050         struct net *net = dev_net(dev);
2051         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
2052         struct ip_tunnel_encap ipencap;
2053         struct ip6_tnl *nt, *t;
2054         int err;
2055
2056         nt = netdev_priv(dev);
2057
2058         if (ip6_tnl_netlink_encap_parms(data, &ipencap)) {
2059                 err = ip6_tnl_encap_setup(nt, &ipencap);
2060                 if (err < 0)
2061                         return err;
2062         }
2063
2064         ip6_tnl_netlink_parms(data, &nt->parms);
2065
2066         if (nt->parms.collect_md) {
2067                 if (rtnl_dereference(ip6n->collect_md_tun))
2068                         return -EEXIST;
2069         } else {
2070                 t = ip6_tnl_locate(net, &nt->parms, 0);
2071                 if (!IS_ERR(t))
2072                         return -EEXIST;
2073         }
2074
2075         err = ip6_tnl_create2(dev);
2076         if (!err && tb[IFLA_MTU])
2077                 ip6_tnl_change_mtu(dev, nla_get_u32(tb[IFLA_MTU]));
2078
2079         return err;
2080 }
2081
2082 static int ip6_tnl_changelink(struct net_device *dev, struct nlattr *tb[],
2083                               struct nlattr *data[],
2084                               struct netlink_ext_ack *extack)
2085 {
2086         struct ip6_tnl *t = netdev_priv(dev);
2087         struct __ip6_tnl_parm p;
2088         struct net *net = t->net;
2089         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
2090         struct ip_tunnel_encap ipencap;
2091
2092         if (dev == ip6n->fb_tnl_dev)
2093                 return -EINVAL;
2094
2095         if (ip6_tnl_netlink_encap_parms(data, &ipencap)) {
2096                 int err = ip6_tnl_encap_setup(t, &ipencap);
2097
2098                 if (err < 0)
2099                         return err;
2100         }
2101         ip6_tnl_netlink_parms(data, &p);
2102         if (p.collect_md)
2103                 return -EINVAL;
2104
2105         t = ip6_tnl_locate(net, &p, 0);
2106         if (!IS_ERR(t)) {
2107                 if (t->dev != dev)
2108                         return -EEXIST;
2109         } else
2110                 t = netdev_priv(dev);
2111
2112         return ip6_tnl_update(t, &p);
2113 }
2114
2115 static void ip6_tnl_dellink(struct net_device *dev, struct list_head *head)
2116 {
2117         struct net *net = dev_net(dev);
2118         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
2119
2120         if (dev != ip6n->fb_tnl_dev)
2121                 unregister_netdevice_queue(dev, head);
2122 }
2123
2124 static size_t ip6_tnl_get_size(const struct net_device *dev)
2125 {
2126         return
2127                 /* IFLA_IPTUN_LINK */
2128                 nla_total_size(4) +
2129                 /* IFLA_IPTUN_LOCAL */
2130                 nla_total_size(sizeof(struct in6_addr)) +
2131                 /* IFLA_IPTUN_REMOTE */
2132                 nla_total_size(sizeof(struct in6_addr)) +
2133                 /* IFLA_IPTUN_TTL */
2134                 nla_total_size(1) +
2135                 /* IFLA_IPTUN_ENCAP_LIMIT */
2136                 nla_total_size(1) +
2137                 /* IFLA_IPTUN_FLOWINFO */
2138                 nla_total_size(4) +
2139                 /* IFLA_IPTUN_FLAGS */
2140                 nla_total_size(4) +
2141                 /* IFLA_IPTUN_PROTO */
2142                 nla_total_size(1) +
2143                 /* IFLA_IPTUN_ENCAP_TYPE */
2144                 nla_total_size(2) +
2145                 /* IFLA_IPTUN_ENCAP_FLAGS */
2146                 nla_total_size(2) +
2147                 /* IFLA_IPTUN_ENCAP_SPORT */
2148                 nla_total_size(2) +
2149                 /* IFLA_IPTUN_ENCAP_DPORT */
2150                 nla_total_size(2) +
2151                 /* IFLA_IPTUN_COLLECT_METADATA */
2152                 nla_total_size(0) +
2153                 /* IFLA_IPTUN_FWMARK */
2154                 nla_total_size(4) +
2155                 0;
2156 }
2157
2158 static int ip6_tnl_fill_info(struct sk_buff *skb, const struct net_device *dev)
2159 {
2160         struct ip6_tnl *tunnel = netdev_priv(dev);
2161         struct __ip6_tnl_parm *parm = &tunnel->parms;
2162
2163         if (nla_put_u32(skb, IFLA_IPTUN_LINK, parm->link) ||
2164             nla_put_in6_addr(skb, IFLA_IPTUN_LOCAL, &parm->laddr) ||
2165             nla_put_in6_addr(skb, IFLA_IPTUN_REMOTE, &parm->raddr) ||
2166             nla_put_u8(skb, IFLA_IPTUN_TTL, parm->hop_limit) ||
2167             nla_put_u8(skb, IFLA_IPTUN_ENCAP_LIMIT, parm->encap_limit) ||
2168             nla_put_be32(skb, IFLA_IPTUN_FLOWINFO, parm->flowinfo) ||
2169             nla_put_u32(skb, IFLA_IPTUN_FLAGS, parm->flags) ||
2170             nla_put_u8(skb, IFLA_IPTUN_PROTO, parm->proto) ||
2171             nla_put_u32(skb, IFLA_IPTUN_FWMARK, parm->fwmark))
2172                 goto nla_put_failure;
2173
2174         if (nla_put_u16(skb, IFLA_IPTUN_ENCAP_TYPE, tunnel->encap.type) ||
2175             nla_put_be16(skb, IFLA_IPTUN_ENCAP_SPORT, tunnel->encap.sport) ||
2176             nla_put_be16(skb, IFLA_IPTUN_ENCAP_DPORT, tunnel->encap.dport) ||
2177             nla_put_u16(skb, IFLA_IPTUN_ENCAP_FLAGS, tunnel->encap.flags))
2178                 goto nla_put_failure;
2179
2180         if (parm->collect_md)
2181                 if (nla_put_flag(skb, IFLA_IPTUN_COLLECT_METADATA))
2182                         goto nla_put_failure;
2183
2184         return 0;
2185
2186 nla_put_failure:
2187         return -EMSGSIZE;
2188 }
2189
2190 struct net *ip6_tnl_get_link_net(const struct net_device *dev)
2191 {
2192         struct ip6_tnl *tunnel = netdev_priv(dev);
2193
2194         return tunnel->net;
2195 }
2196 EXPORT_SYMBOL(ip6_tnl_get_link_net);
2197
2198 static const struct nla_policy ip6_tnl_policy[IFLA_IPTUN_MAX + 1] = {
2199         [IFLA_IPTUN_LINK]               = { .type = NLA_U32 },
2200         [IFLA_IPTUN_LOCAL]              = { .len = sizeof(struct in6_addr) },
2201         [IFLA_IPTUN_REMOTE]             = { .len = sizeof(struct in6_addr) },
2202         [IFLA_IPTUN_TTL]                = { .type = NLA_U8 },
2203         [IFLA_IPTUN_ENCAP_LIMIT]        = { .type = NLA_U8 },
2204         [IFLA_IPTUN_FLOWINFO]           = { .type = NLA_U32 },
2205         [IFLA_IPTUN_FLAGS]              = { .type = NLA_U32 },
2206         [IFLA_IPTUN_PROTO]              = { .type = NLA_U8 },
2207         [IFLA_IPTUN_ENCAP_TYPE]         = { .type = NLA_U16 },
2208         [IFLA_IPTUN_ENCAP_FLAGS]        = { .type = NLA_U16 },
2209         [IFLA_IPTUN_ENCAP_SPORT]        = { .type = NLA_U16 },
2210         [IFLA_IPTUN_ENCAP_DPORT]        = { .type = NLA_U16 },
2211         [IFLA_IPTUN_COLLECT_METADATA]   = { .type = NLA_FLAG },
2212         [IFLA_IPTUN_FWMARK]             = { .type = NLA_U32 },
2213 };
2214
2215 static struct rtnl_link_ops ip6_link_ops __read_mostly = {
2216         .kind           = "ip6tnl",
2217         .maxtype        = IFLA_IPTUN_MAX,
2218         .policy         = ip6_tnl_policy,
2219         .priv_size      = sizeof(struct ip6_tnl),
2220         .setup          = ip6_tnl_dev_setup,
2221         .validate       = ip6_tnl_validate,
2222         .newlink        = ip6_tnl_newlink,
2223         .changelink     = ip6_tnl_changelink,
2224         .dellink        = ip6_tnl_dellink,
2225         .get_size       = ip6_tnl_get_size,
2226         .fill_info      = ip6_tnl_fill_info,
2227         .get_link_net   = ip6_tnl_get_link_net,
2228 };
2229
2230 static struct xfrm6_tunnel ip4ip6_handler __read_mostly = {
2231         .handler        = ip4ip6_rcv,
2232         .err_handler    = ip4ip6_err,
2233         .priority       =       1,
2234 };
2235
2236 static struct xfrm6_tunnel ip6ip6_handler __read_mostly = {
2237         .handler        = ip6ip6_rcv,
2238         .err_handler    = ip6ip6_err,
2239         .priority       =       1,
2240 };
2241
2242 static struct xfrm6_tunnel mplsip6_handler __read_mostly = {
2243         .handler        = mplsip6_rcv,
2244         .err_handler    = mplsip6_err,
2245         .priority       =       1,
2246 };
2247
2248 static void __net_exit ip6_tnl_destroy_tunnels(struct net *net, struct list_head *list)
2249 {
2250         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
2251         struct net_device *dev, *aux;
2252         int h;
2253         struct ip6_tnl *t;
2254
2255         for_each_netdev_safe(net, dev, aux)
2256                 if (dev->rtnl_link_ops == &ip6_link_ops)
2257                         unregister_netdevice_queue(dev, list);
2258
2259         for (h = 0; h < IP6_TUNNEL_HASH_SIZE; h++) {
2260                 t = rtnl_dereference(ip6n->tnls_r_l[h]);
2261                 while (t) {
2262                         /* If dev is in the same netns, it has already
2263                          * been added to the list by the previous loop.
2264                          */
2265                         if (!net_eq(dev_net(t->dev), net))
2266                                 unregister_netdevice_queue(t->dev, list);
2267                         t = rtnl_dereference(t->next);
2268                 }
2269         }
2270 }
2271
2272 static int __net_init ip6_tnl_init_net(struct net *net)
2273 {
2274         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
2275         struct ip6_tnl *t = NULL;
2276         int err;
2277
2278         ip6n->tnls[0] = ip6n->tnls_wc;
2279         ip6n->tnls[1] = ip6n->tnls_r_l;
2280
2281         if (!net_has_fallback_tunnels(net))
2282                 return 0;
2283         err = -ENOMEM;
2284         ip6n->fb_tnl_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6tnl0",
2285                                         NET_NAME_UNKNOWN, ip6_tnl_dev_setup);
2286
2287         if (!ip6n->fb_tnl_dev)
2288                 goto err_alloc_dev;
2289         dev_net_set(ip6n->fb_tnl_dev, net);
2290         ip6n->fb_tnl_dev->rtnl_link_ops = &ip6_link_ops;
2291         /* FB netdevice is special: we have one, and only one per netns.
2292          * Allowing to move it to another netns is clearly unsafe.
2293          */
2294         ip6n->fb_tnl_dev->features |= NETIF_F_NETNS_LOCAL;
2295
2296         err = ip6_fb_tnl_dev_init(ip6n->fb_tnl_dev);
2297         if (err < 0)
2298                 goto err_register;
2299
2300         err = register_netdev(ip6n->fb_tnl_dev);
2301         if (err < 0)
2302                 goto err_register;
2303
2304         t = netdev_priv(ip6n->fb_tnl_dev);
2305
2306         strcpy(t->parms.name, ip6n->fb_tnl_dev->name);
2307         return 0;
2308
2309 err_register:
2310         free_netdev(ip6n->fb_tnl_dev);
2311 err_alloc_dev:
2312         return err;
2313 }
2314
2315 static void __net_exit ip6_tnl_exit_batch_net(struct list_head *net_list)
2316 {
2317         struct net *net;
2318         LIST_HEAD(list);
2319
2320         rtnl_lock();
2321         list_for_each_entry(net, net_list, exit_list)
2322                 ip6_tnl_destroy_tunnels(net, &list);
2323         unregister_netdevice_many(&list);
2324         rtnl_unlock();
2325 }
2326
2327 static struct pernet_operations ip6_tnl_net_ops = {
2328         .init = ip6_tnl_init_net,
2329         .exit_batch = ip6_tnl_exit_batch_net,
2330         .id   = &ip6_tnl_net_id,
2331         .size = sizeof(struct ip6_tnl_net),
2332 };
2333
2334 /**
2335  * ip6_tunnel_init - register protocol and reserve needed resources
2336  *
2337  * Return: 0 on success
2338  **/
2339
2340 static int __init ip6_tunnel_init(void)
2341 {
2342         int  err;
2343
2344         if (!ipv6_mod_enabled())
2345                 return -EOPNOTSUPP;
2346
2347         err = register_pernet_device(&ip6_tnl_net_ops);
2348         if (err < 0)
2349                 goto out_pernet;
2350
2351         err = xfrm6_tunnel_register(&ip4ip6_handler, AF_INET);
2352         if (err < 0) {
2353                 pr_err("%s: can't register ip4ip6\n", __func__);
2354                 goto out_ip4ip6;
2355         }
2356
2357         err = xfrm6_tunnel_register(&ip6ip6_handler, AF_INET6);
2358         if (err < 0) {
2359                 pr_err("%s: can't register ip6ip6\n", __func__);
2360                 goto out_ip6ip6;
2361         }
2362
2363         if (ip6_tnl_mpls_supported()) {
2364                 err = xfrm6_tunnel_register(&mplsip6_handler, AF_MPLS);
2365                 if (err < 0) {
2366                         pr_err("%s: can't register mplsip6\n", __func__);
2367                         goto out_mplsip6;
2368                 }
2369         }
2370
2371         err = rtnl_link_register(&ip6_link_ops);
2372         if (err < 0)
2373                 goto rtnl_link_failed;
2374
2375         return 0;
2376
2377 rtnl_link_failed:
2378         if (ip6_tnl_mpls_supported())
2379                 xfrm6_tunnel_deregister(&mplsip6_handler, AF_MPLS);
2380 out_mplsip6:
2381         xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6);
2382 out_ip6ip6:
2383         xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET);
2384 out_ip4ip6:
2385         unregister_pernet_device(&ip6_tnl_net_ops);
2386 out_pernet:
2387         return err;
2388 }
2389
2390 /**
2391  * ip6_tunnel_cleanup - free resources and unregister protocol
2392  **/
2393
2394 static void __exit ip6_tunnel_cleanup(void)
2395 {
2396         rtnl_link_unregister(&ip6_link_ops);
2397         if (xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET))
2398                 pr_info("%s: can't deregister ip4ip6\n", __func__);
2399
2400         if (xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6))
2401                 pr_info("%s: can't deregister ip6ip6\n", __func__);
2402
2403         if (ip6_tnl_mpls_supported() &&
2404             xfrm6_tunnel_deregister(&mplsip6_handler, AF_MPLS))
2405                 pr_info("%s: can't deregister mplsip6\n", __func__);
2406         unregister_pernet_device(&ip6_tnl_net_ops);
2407 }
2408
2409 module_init(ip6_tunnel_init);
2410 module_exit(ip6_tunnel_cleanup);