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