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         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  *   @net: network namespace
 306  *   @p: tunnel parameters
 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  *   @net: network namespace
 355  *   @p: tunnel parameters
 356  *   @create: != 0 if allowed to create new tunnel if no match found
 357  *
 358  * Description:
 359  *   ip6_tnl_locate() first tries to locate an existing tunnel
 360  *   based on @parms. If this is unsuccessful, but @create is set a new
 361  *   tunnel device is created and registered for use.
 362  *
 363  * Return:
 364  *   matching tunnel or error pointer
 365  **/
 366
 367 static struct ip6_tnl *ip6_tnl_locate(struct net *net,
 368                 struct __ip6_tnl_parm *p, int create)
 369 {
 370         const struct in6_addr *remote = &p->raddr;
 371         const struct in6_addr *local = &p->laddr;
 372         struct ip6_tnl __rcu **tp;
 373         struct ip6_tnl *t;
 374         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
 375
 376         for (tp = ip6_tnl_bucket(ip6n, p);
 377              (t = rtnl_dereference(*tp)) != NULL;
 378              tp = &t->next) {
 379                 if (ipv6_addr_equal(local, &t->parms.laddr) &&
 380                     ipv6_addr_equal(remote, &t->parms.raddr) &&
 381                     p->link == t->parms.link) {
 382                         if (create)
 383                                 return ERR_PTR(-EEXIST);
 384
 385                         return t;
 386                 }
 387         }
 388         if (!create)
 389                 return ERR_PTR(-ENODEV);
 390         return ip6_tnl_create(net, p);
 391 }
 392
 393 /**
 394  * ip6_tnl_dev_uninit - tunnel device uninitializer
 395  *   @dev: the device to be destroyed
 396  *
 397  * Description:
 398  *   ip6_tnl_dev_uninit() removes tunnel from its list
 399  **/
 400
 401 static void
 402 ip6_tnl_dev_uninit(struct net_device *dev)
 403 {
 404         struct ip6_tnl *t = netdev_priv(dev);
 405         struct net *net = t->net;
 406         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
 407
 408         if (dev == ip6n->fb_tnl_dev)
 409                 RCU_INIT_POINTER(ip6n->tnls_wc[0], NULL);
 410         else
 411                 ip6_tnl_unlink(ip6n, t);
 412         dst_cache_reset(&t->dst_cache);
 413         dev_put(dev);
 414 }
 415
 416 /**
 417  * parse_tvl_tnl_enc_lim - handle encapsulation limit option
 418  *   @skb: received socket buffer
 419  *
 420  * Return:
 421  *   0 if none was found,
 422  *   else index to encapsulation limit
 423  **/
 424
 425 __u16 ip6_tnl_parse_tlv_enc_lim(struct sk_buff *skb, __u8 *raw)
 426 {
 427         const struct ipv6hdr *ipv6h = (const struct ipv6hdr *)raw;
 428         unsigned int nhoff = raw - skb->data;
 429         unsigned int off = nhoff + sizeof(*ipv6h);
 430         u8 next, nexthdr = ipv6h->nexthdr;
 431
 432         while (ipv6_ext_hdr(nexthdr) && nexthdr != NEXTHDR_NONE) {
 433                 struct ipv6_opt_hdr *hdr;
 434                 u16 optlen;
 435
 436                 if (!pskb_may_pull(skb, off + sizeof(*hdr)))
 437                         break;
 438
 439                 hdr = (struct ipv6_opt_hdr *)(skb->data + off);
 440                 if (nexthdr == NEXTHDR_FRAGMENT) {
 441                         struct frag_hdr *frag_hdr = (struct frag_hdr *) hdr;
 442                         if (frag_hdr->frag_off)
 443                                 break;
 444                         optlen = 8;
 445                 } else if (nexthdr == NEXTHDR_AUTH) {
 446                         optlen = ipv6_authlen(hdr);
 447                 } else {
 448                         optlen = ipv6_optlen(hdr);
 449                 }
 450                 /* cache hdr->nexthdr, since pskb_may_pull() might
 451                  * invalidate hdr
 452                  */
 453                 next = hdr->nexthdr;
 454                 if (nexthdr == NEXTHDR_DEST) {
 455                         u16 i = 2;
 456
 457                         /* Remember : hdr is no longer valid at this point. */
 458                         if (!pskb_may_pull(skb, off + optlen))
 459                                 break;
 460
 461                         while (1) {
 462                                 struct ipv6_tlv_tnl_enc_lim *tel;
 463
 464                                 /* No more room for encapsulation limit */
 465                                 if (i + sizeof(*tel) > optlen)
 466                                         break;
 467
 468                                 tel = (struct ipv6_tlv_tnl_enc_lim *)(skb->data + off + i);
 469                                 /* return index of option if found and valid */
 470                                 if (tel->type == IPV6_TLV_TNL_ENCAP_LIMIT &&
 471                                     tel->length == 1)
 472                                         return i + off - nhoff;
 473                                 /* else jump to next option */
 474                                 if (tel->type)
 475                                         i += tel->length + 2;
 476                                 else
 477                                         i++;
 478                         }
 479                 }
 480                 nexthdr = next;
 481                 off += optlen;
 482         }
 483         return 0;
 484 }
 485 EXPORT_SYMBOL(ip6_tnl_parse_tlv_enc_lim);
 486
 487 /**
 488  * ip6_tnl_err - tunnel error handler
 489  *
 490  * Description:
 491  *   ip6_tnl_err() should handle errors in the tunnel according
 492  *   to the specifications in RFC 2473.
 493  **/
 494
 495 static int
 496 ip6_tnl_err(struct sk_buff *skb, __u8 ipproto, struct inet6_skb_parm *opt,
 497             u8 *type, u8 *code, int *msg, __u32 *info, int offset)
 498 {
 499         const struct ipv6hdr *ipv6h = (const struct ipv6hdr *)skb->data;
 500         struct net *net = dev_net(skb->dev);
 501         u8 rel_type = ICMPV6_DEST_UNREACH;
 502         u8 rel_code = ICMPV6_ADDR_UNREACH;
 503         __u32 rel_info = 0;
 504         struct ip6_tnl *t;
 505         int err = -ENOENT;
 506         int rel_msg = 0;
 507         u8 tproto;
 508         __u16 len;
 509
 510         /* If the packet doesn't contain the original IPv6 header we are
 511            in trouble since we might need the source address for further
 512            processing of the error. */
 513
 514         rcu_read_lock();
 515         t = ip6_tnl_lookup(dev_net(skb->dev), skb->dev->ifindex, &ipv6h->daddr, &ipv6h->saddr);
 516         if (!t)
 517                 goto out;
 518
 519         tproto = READ_ONCE(t->parms.proto);
 520         if (tproto != ipproto && tproto != 0)
 521                 goto out;
 522
 523         err = 0;
 524
 525         switch (*type) {
 526         case ICMPV6_DEST_UNREACH:
 527                 net_dbg_ratelimited("%s: Path to destination invalid or inactive!\n",
 528                                     t->parms.name);
 529                 rel_msg = 1;
 530                 break;
 531         case ICMPV6_TIME_EXCEED:
 532                 if ((*code) == ICMPV6_EXC_HOPLIMIT) {
 533                         net_dbg_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n",
 534                                             t->parms.name);
 535                         rel_msg = 1;
 536                 }
 537                 break;
 538         case ICMPV6_PARAMPROB: {
 539                 struct ipv6_tlv_tnl_enc_lim *tel;
 540                 __u32 teli;
 541
 542                 teli = 0;
 543                 if ((*code) == ICMPV6_HDR_FIELD)
 544                         teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data);
 545
 546                 if (teli && teli == *info - 2) {
 547                         tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli];
 548                         if (tel->encap_limit == 0) {
 549                                 net_dbg_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n",
 550                                                     t->parms.name);
 551                                 rel_msg = 1;
 552                         }
 553                 } else {
 554                         net_dbg_ratelimited("%s: Recipient unable to parse tunneled packet!\n",
 555                                             t->parms.name);
 556                 }
 557                 break;
 558         }
 559         case ICMPV6_PKT_TOOBIG: {
 560                 __u32 mtu;
 561
 562                 ip6_update_pmtu(skb, net, htonl(*info), 0, 0,
 563                                 sock_net_uid(net, NULL));
 564                 mtu = *info - offset;
 565                 if (mtu < IPV6_MIN_MTU)
 566                         mtu = IPV6_MIN_MTU;
 567                 len = sizeof(*ipv6h) + ntohs(ipv6h->payload_len);
 568                 if (len > mtu) {
 569                         rel_type = ICMPV6_PKT_TOOBIG;
 570                         rel_code = 0;
 571                         rel_info = mtu;
 572                         rel_msg = 1;
 573                 }
 574                 break;
 575         }
 576         case NDISC_REDIRECT:
 577                 ip6_redirect(skb, net, skb->dev->ifindex, 0,
 578                              sock_net_uid(net, NULL));
 579                 break;
 580         }
 581
 582         *type = rel_type;
 583         *code = rel_code;
 584         *info = rel_info;
 585         *msg = rel_msg;
 586
 587 out:
 588         rcu_read_unlock();
 589         return err;
 590 }
 591
 592 static int
 593 ip4ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 594            u8 type, u8 code, int offset, __be32 info)
 595 {
 596         __u32 rel_info = ntohl(info);
 597         const struct iphdr *eiph;
 598         struct sk_buff *skb2;
 599         int err, rel_msg = 0;
 600         u8 rel_type = type;
 601         u8 rel_code = code;
 602         struct rtable *rt;
 603         struct flowi4 fl4;
 604
 605         err = ip6_tnl_err(skb, IPPROTO_IPIP, opt, &rel_type, &rel_code,
 606                           &rel_msg, &rel_info, offset);
 607         if (err < 0)
 608                 return err;
 609
 610         if (rel_msg == 0)
 611                 return 0;
 612
 613         switch (rel_type) {
 614         case ICMPV6_DEST_UNREACH:
 615                 if (rel_code != ICMPV6_ADDR_UNREACH)
 616                         return 0;
 617                 rel_type = ICMP_DEST_UNREACH;
 618                 rel_code = ICMP_HOST_UNREACH;
 619                 break;
 620         case ICMPV6_PKT_TOOBIG:
 621                 if (rel_code != 0)
 622                         return 0;
 623                 rel_type = ICMP_DEST_UNREACH;
 624                 rel_code = ICMP_FRAG_NEEDED;
 625                 break;
 626         default:
 627                 return 0;
 628         }
 629
 630         if (!pskb_may_pull(skb, offset + sizeof(struct iphdr)))
 631                 return 0;
 632
 633         skb2 = skb_clone(skb, GFP_ATOMIC);
 634         if (!skb2)
 635                 return 0;
 636
 637         skb_dst_drop(skb2);
 638
 639         skb_pull(skb2, offset);
 640         skb_reset_network_header(skb2);
 641         eiph = ip_hdr(skb2);
 642
 643         /* Try to guess incoming interface */
 644         rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL, eiph->saddr,
 645                                    0, 0, 0, IPPROTO_IPIP, RT_TOS(eiph->tos), 0);
 646         if (IS_ERR(rt))
 647                 goto out;
 648
 649         skb2->dev = rt->dst.dev;
 650         ip_rt_put(rt);
 651
 652         /* route "incoming" packet */
 653         if (rt->rt_flags & RTCF_LOCAL) {
 654                 rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL,
 655                                            eiph->daddr, eiph->saddr, 0, 0,
 656                                            IPPROTO_IPIP, RT_TOS(eiph->tos), 0);
 657                 if (IS_ERR(rt) || rt->dst.dev->type != ARPHRD_TUNNEL6) {
 658                         if (!IS_ERR(rt))
 659                                 ip_rt_put(rt);
 660                         goto out;
 661                 }
 662                 skb_dst_set(skb2, &rt->dst);
 663         } else {
 664                 if (ip_route_input(skb2, eiph->daddr, eiph->saddr, eiph->tos,
 665                                    skb2->dev) ||
 666                     skb_dst(skb2)->dev->type != ARPHRD_TUNNEL6)
 667                         goto out;
 668         }
 669
 670         /* change mtu on this route */
 671         if (rel_type == ICMP_DEST_UNREACH && rel_code == ICMP_FRAG_NEEDED) {
 672                 if (rel_info > dst_mtu(skb_dst(skb2)))
 673                         goto out;
 674
 675                 skb_dst_update_pmtu_no_confirm(skb2, rel_info);
 676         }
 677
 678         icmp_send(skb2, rel_type, rel_code, htonl(rel_info));
 679
 680 out:
 681         kfree_skb(skb2);
 682         return 0;
 683 }
 684
 685 static int
 686 ip6ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 687            u8 type, u8 code, int offset, __be32 info)
 688 {
 689         __u32 rel_info = ntohl(info);
 690         int err, rel_msg = 0;
 691         u8 rel_type = type;
 692         u8 rel_code = code;
 693
 694         err = ip6_tnl_err(skb, IPPROTO_IPV6, opt, &rel_type, &rel_code,
 695                           &rel_msg, &rel_info, offset);
 696         if (err < 0)
 697                 return err;
 698
 699         if (rel_msg && pskb_may_pull(skb, offset + sizeof(struct ipv6hdr))) {
 700                 struct rt6_info *rt;
 701                 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
 702
 703                 if (!skb2)
 704                         return 0;
 705
 706                 skb_dst_drop(skb2);
 707                 skb_pull(skb2, offset);
 708                 skb_reset_network_header(skb2);
 709
 710                 /* Try to guess incoming interface */
 711                 rt = rt6_lookup(dev_net(skb->dev), &ipv6_hdr(skb2)->saddr,
 712                                 NULL, 0, skb2, 0);
 713
 714                 if (rt && rt->dst.dev)
 715                         skb2->dev = rt->dst.dev;
 716
 717                 icmpv6_send(skb2, rel_type, rel_code, rel_info);
 718
 719                 ip6_rt_put(rt);
 720
 721                 kfree_skb(skb2);
 722         }
 723
 724         return 0;
 725 }
 726
 727 static int
 728 mplsip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 729             u8 type, u8 code, int offset, __be32 info)
 730 {
 731         __u32 rel_info = ntohl(info);
 732         int err, rel_msg = 0;
 733         u8 rel_type = type;
 734         u8 rel_code = code;
 735
 736         err = ip6_tnl_err(skb, IPPROTO_MPLS, opt, &rel_type, &rel_code,
 737                           &rel_msg, &rel_info, offset);
 738         return err;
 739 }
 740
 741 static int ip4ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t,
 742                                        const struct ipv6hdr *ipv6h,
 743                                        struct sk_buff *skb)
 744 {
 745         __u8 dsfield = ipv6_get_dsfield(ipv6h) & ~INET_ECN_MASK;
 746
 747         if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY)
 748                 ipv4_change_dsfield(ip_hdr(skb), INET_ECN_MASK, dsfield);
 749
 750         return IP6_ECN_decapsulate(ipv6h, skb);
 751 }
 752
 753 static int ip6ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t,
 754                                        const struct ipv6hdr *ipv6h,
 755                                        struct sk_buff *skb)
 756 {
 757         if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY)
 758                 ipv6_copy_dscp(ipv6_get_dsfield(ipv6h), ipv6_hdr(skb));
 759
 760         return IP6_ECN_decapsulate(ipv6h, skb);
 761 }
 762
 763 static inline int mplsip6_dscp_ecn_decapsulate(const struct ip6_tnl *t,
 764                                                const struct ipv6hdr *ipv6h,
 765                                                struct sk_buff *skb)
 766 {
 767         /* ECN is not supported in AF_MPLS */
 768         return 0;
 769 }
 770
 771 __u32 ip6_tnl_get_cap(struct ip6_tnl *t,
 772                              const struct in6_addr *laddr,
 773                              const struct in6_addr *raddr)
 774 {
 775         struct __ip6_tnl_parm *p = &t->parms;
 776         int ltype = ipv6_addr_type(laddr);
 777         int rtype = ipv6_addr_type(raddr);
 778         __u32 flags = 0;
 779
 780         if (ltype == IPV6_ADDR_ANY || rtype == IPV6_ADDR_ANY) {
 781                 flags = IP6_TNL_F_CAP_PER_PACKET;
 782         } else if (ltype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) &&
 783                    rtype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) &&
 784                    !((ltype|rtype) & IPV6_ADDR_LOOPBACK) &&
 785                    (!((ltype|rtype) & IPV6_ADDR_LINKLOCAL) || p->link)) {
 786                 if (ltype&IPV6_ADDR_UNICAST)
 787                         flags |= IP6_TNL_F_CAP_XMIT;
 788                 if (rtype&IPV6_ADDR_UNICAST)
 789                         flags |= IP6_TNL_F_CAP_RCV;
 790         }
 791         return flags;
 792 }
 793 EXPORT_SYMBOL(ip6_tnl_get_cap);
 794
 795 /* called with rcu_read_lock() */
 796 int ip6_tnl_rcv_ctl(struct ip6_tnl *t,
 797                                   const struct in6_addr *laddr,
 798                                   const struct in6_addr *raddr)
 799 {
 800         struct __ip6_tnl_parm *p = &t->parms;
 801         int ret = 0;
 802         struct net *net = t->net;
 803
 804         if ((p->flags & IP6_TNL_F_CAP_RCV) ||
 805             ((p->flags & IP6_TNL_F_CAP_PER_PACKET) &&
 806              (ip6_tnl_get_cap(t, laddr, raddr) & IP6_TNL_F_CAP_RCV))) {
 807                 struct net_device *ldev = NULL;
 808
 809                 if (p->link)
 810                         ldev = dev_get_by_index_rcu(net, p->link);
 811
 812                 if ((ipv6_addr_is_multicast(laddr) ||
 813                      likely(ipv6_chk_addr_and_flags(net, laddr, ldev, false,
 814                                                     0, IFA_F_TENTATIVE))) &&
 815                     ((p->flags & IP6_TNL_F_ALLOW_LOCAL_REMOTE) ||
 816                      likely(!ipv6_chk_addr_and_flags(net, raddr, ldev, true,
 817                                                      0, IFA_F_TENTATIVE))))
 818                         ret = 1;
 819         }
 820         return ret;
 821 }
 822 EXPORT_SYMBOL_GPL(ip6_tnl_rcv_ctl);
 823
 824 static int __ip6_tnl_rcv(struct ip6_tnl *tunnel, struct sk_buff *skb,
 825                          const struct tnl_ptk_info *tpi,
 826                          struct metadata_dst *tun_dst,
 827                          int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t,
 828                                                 const struct ipv6hdr *ipv6h,
 829                                                 struct sk_buff *skb),
 830                          bool log_ecn_err)
 831 {
 832         struct pcpu_sw_netstats *tstats;
 833         const struct ipv6hdr *ipv6h = ipv6_hdr(skb);
 834         int err;
 835
 836         if ((!(tpi->flags & TUNNEL_CSUM) &&
 837              (tunnel->parms.i_flags & TUNNEL_CSUM)) ||
 838             ((tpi->flags & TUNNEL_CSUM) &&
 839              !(tunnel->parms.i_flags & TUNNEL_CSUM))) {
 840                 tunnel->dev->stats.rx_crc_errors++;
 841                 tunnel->dev->stats.rx_errors++;
 842                 goto drop;
 843         }
 844
 845         if (tunnel->parms.i_flags & TUNNEL_SEQ) {
 846                 if (!(tpi->flags & TUNNEL_SEQ) ||
 847                     (tunnel->i_seqno &&
 848                      (s32)(ntohl(tpi->seq) - tunnel->i_seqno) < 0)) {
 849                         tunnel->dev->stats.rx_fifo_errors++;
 850                         tunnel->dev->stats.rx_errors++;
 851                         goto drop;
 852                 }
 853                 tunnel->i_seqno = ntohl(tpi->seq) + 1;
 854         }
 855
 856         skb->protocol = tpi->proto;
 857
 858         /* Warning: All skb pointers will be invalidated! */
 859         if (tunnel->dev->type == ARPHRD_ETHER) {
 860                 if (!pskb_may_pull(skb, ETH_HLEN)) {
 861                         tunnel->dev->stats.rx_length_errors++;
 862                         tunnel->dev->stats.rx_errors++;
 863                         goto drop;
 864                 }
 865
 866                 ipv6h = ipv6_hdr(skb);
 867                 skb->protocol = eth_type_trans(skb, tunnel->dev);
 868                 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);
 869         } else {
 870                 skb->dev = tunnel->dev;
 871         }
 872
 873         skb_reset_network_header(skb);
 874         memset(skb->cb, 0, sizeof(struct inet6_skb_parm));
 875
 876         __skb_tunnel_rx(skb, tunnel->dev, tunnel->net);
 877
 878         err = dscp_ecn_decapsulate(tunnel, ipv6h, skb);
 879         if (unlikely(err)) {
 880                 if (log_ecn_err)
 881                         net_info_ratelimited("non-ECT from %pI6 with DS=%#x\n",
 882                                              &ipv6h->saddr,
 883                                              ipv6_get_dsfield(ipv6h));
 884                 if (err > 1) {
 885                         ++tunnel->dev->stats.rx_frame_errors;
 886                         ++tunnel->dev->stats.rx_errors;
 887                         goto drop;
 888                 }
 889         }
 890
 891         tstats = this_cpu_ptr(tunnel->dev->tstats);
 892         u64_stats_update_begin(&tstats->syncp);
 893         tstats->rx_packets++;
 894         tstats->rx_bytes += skb->len;
 895         u64_stats_update_end(&tstats->syncp);
 896
 897         skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(tunnel->dev)));
 898
 899         if (tun_dst)
 900                 skb_dst_set(skb, (struct dst_entry *)tun_dst);
 901
 902         gro_cells_receive(&tunnel->gro_cells, skb);
 903         return 0;
 904
 905 drop:
 906         if (tun_dst)
 907                 dst_release((struct dst_entry *)tun_dst);
 908         kfree_skb(skb);
 909         return 0;
 910 }
 911
 912 int ip6_tnl_rcv(struct ip6_tnl *t, struct sk_buff *skb,
 913                 const struct tnl_ptk_info *tpi,
 914                 struct metadata_dst *tun_dst,
 915                 bool log_ecn_err)
 916 {
 917         int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t,
 918                                     const struct ipv6hdr *ipv6h,
 919                                     struct sk_buff *skb);
 920
 921         dscp_ecn_decapsulate = ip6ip6_dscp_ecn_decapsulate;
 922         if (tpi->proto == htons(ETH_P_IP))
 923                 dscp_ecn_decapsulate = ip4ip6_dscp_ecn_decapsulate;
 924
 925         return __ip6_tnl_rcv(t, skb, tpi, tun_dst, dscp_ecn_decapsulate,
 926                              log_ecn_err);
 927 }
 928 EXPORT_SYMBOL(ip6_tnl_rcv);
 929
 930 static const struct tnl_ptk_info tpi_v6 = {
 931         /* no tunnel info required for ipxip6. */
 932         .proto = htons(ETH_P_IPV6),
 933 };
 934
 935 static const struct tnl_ptk_info tpi_v4 = {
 936         /* no tunnel info required for ipxip6. */
 937         .proto = htons(ETH_P_IP),
 938 };
 939
 940 static const struct tnl_ptk_info tpi_mpls = {
 941         /* no tunnel info required for mplsip6. */
 942         .proto = htons(ETH_P_MPLS_UC),
 943 };
 944
 945 static int ipxip6_rcv(struct sk_buff *skb, u8 ipproto,
 946                       const struct tnl_ptk_info *tpi,
 947                       int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t,
 948                                                   const struct ipv6hdr *ipv6h,
 949                                                   struct sk_buff *skb))
 950 {
 951         struct ip6_tnl *t;
 952         const struct ipv6hdr *ipv6h = ipv6_hdr(skb);
 953         struct metadata_dst *tun_dst = NULL;
 954         int ret = -1;
 955
 956         rcu_read_lock();
 957         t = ip6_tnl_lookup(dev_net(skb->dev), skb->dev->ifindex, &ipv6h->saddr, &ipv6h->daddr);
 958
 959         if (t) {
 960                 u8 tproto = READ_ONCE(t->parms.proto);
 961
 962                 if (tproto != ipproto && tproto != 0)
 963                         goto drop;
 964                 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
 965                         goto drop;
 966                 ipv6h = ipv6_hdr(skb);
 967                 if (!ip6_tnl_rcv_ctl(t, &ipv6h->daddr, &ipv6h->saddr))
 968                         goto drop;
 969                 if (iptunnel_pull_header(skb, 0, tpi->proto, false))
 970                         goto drop;
 971                 if (t->parms.collect_md) {
 972                         tun_dst = ipv6_tun_rx_dst(skb, 0, 0, 0);
 973                         if (!tun_dst)
 974                                 goto drop;
 975                 }
 976                 ret = __ip6_tnl_rcv(t, skb, tpi, tun_dst, dscp_ecn_decapsulate,
 977                                     log_ecn_error);
 978         }
 979
 980         rcu_read_unlock();
 981
 982         return ret;
 983
 984 drop:
 985         rcu_read_unlock();
 986         kfree_skb(skb);
 987         return 0;
 988 }
 989
 990 static int ip4ip6_rcv(struct sk_buff *skb)
 991 {
 992         return ipxip6_rcv(skb, IPPROTO_IPIP, &tpi_v4,
 993                           ip4ip6_dscp_ecn_decapsulate);
 994 }
 995
 996 static int ip6ip6_rcv(struct sk_buff *skb)
 997 {
 998         return ipxip6_rcv(skb, IPPROTO_IPV6, &tpi_v6,
 999                           ip6ip6_dscp_ecn_decapsulate);
1000 }
1001
1002 static int mplsip6_rcv(struct sk_buff *skb)
1003 {
1004         return ipxip6_rcv(skb, IPPROTO_MPLS, &tpi_mpls,
1005                           mplsip6_dscp_ecn_decapsulate);
1006 }
1007
1008 struct ipv6_tel_txoption {
1009         struct ipv6_txoptions ops;
1010         __u8 dst_opt[8];
1011 };
1012
1013 static void init_tel_txopt(struct ipv6_tel_txoption *opt, __u8 encap_limit)
1014 {
1015         memset(opt, 0, sizeof(struct ipv6_tel_txoption));
1016
1017         opt->dst_opt[2] = IPV6_TLV_TNL_ENCAP_LIMIT;
1018         opt->dst_opt[3] = 1;
1019         opt->dst_opt[4] = encap_limit;
1020         opt->dst_opt[5] = IPV6_TLV_PADN;
1021         opt->dst_opt[6] = 1;
1022
1023         opt->ops.dst1opt = (struct ipv6_opt_hdr *) opt->dst_opt;
1024         opt->ops.opt_nflen = 8;
1025 }
1026
1027 /**
1028  * ip6_tnl_addr_conflict - compare packet addresses to tunnel's own
1029  *   @t: the outgoing tunnel device
1030  *   @hdr: IPv6 header from the incoming packet
1031  *
1032  * Description:
1033  *   Avoid trivial tunneling loop by checking that tunnel exit-point
1034  *   doesn't match source of incoming packet.
1035  *
1036  * Return:
1037  *   1 if conflict,
1038  *   0 else
1039  **/
1040
1041 static inline bool
1042 ip6_tnl_addr_conflict(const struct ip6_tnl *t, const struct ipv6hdr *hdr)
1043 {
1044         return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr);
1045 }
1046
1047 int ip6_tnl_xmit_ctl(struct ip6_tnl *t,
1048                      const struct in6_addr *laddr,
1049                      const struct in6_addr *raddr)
1050 {
1051         struct __ip6_tnl_parm *p = &t->parms;
1052         int ret = 0;
1053         struct net *net = t->net;
1054
1055         if (t->parms.collect_md)
1056                 return 1;
1057
1058         if ((p->flags & IP6_TNL_F_CAP_XMIT) ||
1059             ((p->flags & IP6_TNL_F_CAP_PER_PACKET) &&
1060              (ip6_tnl_get_cap(t, laddr, raddr) & IP6_TNL_F_CAP_XMIT))) {
1061                 struct net_device *ldev = NULL;
1062
1063                 rcu_read_lock();
1064                 if (p->link)
1065                         ldev = dev_get_by_index_rcu(net, p->link);
1066
1067                 if (unlikely(!ipv6_chk_addr_and_flags(net, laddr, ldev, false,
1068                                                       0, IFA_F_TENTATIVE)))
1069                         pr_warn_ratelimited("%s xmit: Local address not yet configured!\n",
1070                                             p->name);
1071                 else if (!(p->flags & IP6_TNL_F_ALLOW_LOCAL_REMOTE) &&
1072                          !ipv6_addr_is_multicast(raddr) &&
1073                          unlikely(ipv6_chk_addr_and_flags(net, raddr, ldev,
1074                                                           true, 0, IFA_F_TENTATIVE)))
1075                         pr_warn_ratelimited("%s xmit: Routing loop! Remote address found on this node!\n",
1076                                             p->name);
1077                 else
1078                         ret = 1;
1079                 rcu_read_unlock();
1080         }
1081         return ret;
1082 }
1083 EXPORT_SYMBOL_GPL(ip6_tnl_xmit_ctl);
1084
1085 /**
1086  * ip6_tnl_xmit - encapsulate packet and send
1087  *   @skb: the outgoing socket buffer
1088  *   @dev: the outgoing tunnel device
1089  *   @dsfield: dscp code for outer header
1090  *   @fl6: flow of tunneled packet
1091  *   @encap_limit: encapsulation limit
1092  *   @pmtu: Path MTU is stored if packet is too big
1093  *   @proto: next header value
1094  *
1095  * Description:
1096  *   Build new header and do some sanity checks on the packet before sending
1097  *   it.
1098  *
1099  * Return:
1100  *   0 on success
1101  *   -1 fail
1102  *   %-EMSGSIZE message too big. return mtu in this case.
1103  **/
1104
1105 int ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev, __u8 dsfield,
1106                  struct flowi6 *fl6, int encap_limit, __u32 *pmtu,
1107                  __u8 proto)
1108 {
1109         struct ip6_tnl *t = netdev_priv(dev);
1110         struct net *net = t->net;
1111         struct net_device_stats *stats = &t->dev->stats;
1112         struct ipv6hdr *ipv6h;
1113         struct ipv6_tel_txoption opt;
1114         struct dst_entry *dst = NULL, *ndst = NULL;
1115         struct net_device *tdev;
1116         int mtu;
1117         unsigned int eth_hlen = t->dev->type == ARPHRD_ETHER ? ETH_HLEN : 0;
1118         unsigned int psh_hlen = sizeof(struct ipv6hdr) + t->encap_hlen;
1119         unsigned int max_headroom = psh_hlen;
1120         bool use_cache = false;
1121         u8 hop_limit;
1122         int err = -1;
1123
1124         if (t->parms.collect_md) {
1125                 hop_limit = skb_tunnel_info(skb)->key.ttl;
1126                 goto route_lookup;
1127         } else {
1128                 hop_limit = t->parms.hop_limit;
1129         }
1130
1131         /* NBMA tunnel */
1132         if (ipv6_addr_any(&t->parms.raddr)) {
1133                 if (skb->protocol == htons(ETH_P_IPV6)) {
1134                         struct in6_addr *addr6;
1135                         struct neighbour *neigh;
1136                         int addr_type;
1137
1138                         if (!skb_dst(skb))
1139                                 goto tx_err_link_failure;
1140
1141                         neigh = dst_neigh_lookup(skb_dst(skb),
1142                                                  &ipv6_hdr(skb)->daddr);
1143                         if (!neigh)
1144                                 goto tx_err_link_failure;
1145
1146                         addr6 = (struct in6_addr *)&neigh->primary_key;
1147                         addr_type = ipv6_addr_type(addr6);
1148
1149                         if (addr_type == IPV6_ADDR_ANY)
1150                                 addr6 = &ipv6_hdr(skb)->daddr;
1151
1152                         memcpy(&fl6->daddr, addr6, sizeof(fl6->daddr));
1153                         neigh_release(neigh);
1154                 }
1155         } else if (t->parms.proto != 0 && !(t->parms.flags &
1156                                             (IP6_TNL_F_USE_ORIG_TCLASS |
1157                                              IP6_TNL_F_USE_ORIG_FWMARK))) {
1158                 /* enable the cache only if neither the outer protocol nor the
1159                  * routing decision depends on the current inner header value
1160                  */
1161                 use_cache = true;
1162         }
1163
1164         if (use_cache)
1165                 dst = dst_cache_get(&t->dst_cache);
1166
1167         if (!ip6_tnl_xmit_ctl(t, &fl6->saddr, &fl6->daddr))
1168                 goto tx_err_link_failure;
1169
1170         if (!dst) {
1171 route_lookup:
1172                 /* add dsfield to flowlabel for route lookup */
1173                 fl6->flowlabel = ip6_make_flowinfo(dsfield, fl6->flowlabel);
1174
1175                 dst = ip6_route_output(net, NULL, fl6);
1176
1177                 if (dst->error)
1178                         goto tx_err_link_failure;
1179                 dst = xfrm_lookup(net, dst, flowi6_to_flowi(fl6), NULL, 0);
1180                 if (IS_ERR(dst)) {
1181                         err = PTR_ERR(dst);
1182                         dst = NULL;
1183                         goto tx_err_link_failure;
1184                 }
1185                 if (t->parms.collect_md && ipv6_addr_any(&fl6->saddr) &&
1186                     ipv6_dev_get_saddr(net, ip6_dst_idev(dst)->dev,
1187                                        &fl6->daddr, 0, &fl6->saddr))
1188                         goto tx_err_link_failure;
1189                 ndst = dst;
1190         }
1191
1192         tdev = dst->dev;
1193
1194         if (tdev == dev) {
1195                 stats->collisions++;
1196                 net_warn_ratelimited("%s: Local routing loop detected!\n",
1197                                      t->parms.name);
1198                 goto tx_err_dst_release;
1199         }
1200         mtu = dst_mtu(dst) - eth_hlen - psh_hlen - t->tun_hlen;
1201         if (encap_limit >= 0) {
1202                 max_headroom += 8;
1203                 mtu -= 8;
1204         }
1205         mtu = max(mtu, skb->protocol == htons(ETH_P_IPV6) ?
1206                        IPV6_MIN_MTU : IPV4_MIN_MTU);
1207
1208         skb_dst_update_pmtu_no_confirm(skb, mtu);
1209         if (skb->len - t->tun_hlen - eth_hlen > mtu && !skb_is_gso(skb)) {
1210                 *pmtu = mtu;
1211                 err = -EMSGSIZE;
1212                 goto tx_err_dst_release;
1213         }
1214
1215         if (t->err_count > 0) {
1216                 if (time_before(jiffies,
1217                                 t->err_time + IP6TUNNEL_ERR_TIMEO)) {
1218                         t->err_count--;
1219
1220                         dst_link_failure(skb);
1221                 } else {
1222                         t->err_count = 0;
1223                 }
1224         }
1225
1226         skb_scrub_packet(skb, !net_eq(t->net, dev_net(dev)));
1227
1228         /*
1229          * Okay, now see if we can stuff it in the buffer as-is.
1230          */
1231         max_headroom += LL_RESERVED_SPACE(tdev);
1232
1233         if (skb_headroom(skb) < max_headroom || skb_shared(skb) ||
1234             (skb_cloned(skb) && !skb_clone_writable(skb, 0))) {
1235                 struct sk_buff *new_skb;
1236
1237                 new_skb = skb_realloc_headroom(skb, max_headroom);
1238                 if (!new_skb)
1239                         goto tx_err_dst_release;
1240
1241                 if (skb->sk)
1242                         skb_set_owner_w(new_skb, skb->sk);
1243                 consume_skb(skb);
1244                 skb = new_skb;
1245         }
1246
1247         if (t->parms.collect_md) {
1248                 if (t->encap.type != TUNNEL_ENCAP_NONE)
1249                         goto tx_err_dst_release;
1250         } else {
1251                 if (use_cache && ndst)
1252                         dst_cache_set_ip6(&t->dst_cache, ndst, &fl6->saddr);
1253         }
1254         skb_dst_set(skb, dst);
1255
1256         if (hop_limit == 0) {
1257                 if (skb->protocol == htons(ETH_P_IP))
1258                         hop_limit = ip_hdr(skb)->ttl;
1259                 else if (skb->protocol == htons(ETH_P_IPV6))
1260                         hop_limit = ipv6_hdr(skb)->hop_limit;
1261                 else
1262                         hop_limit = ip6_dst_hoplimit(dst);
1263         }
1264
1265         /* Calculate max headroom for all the headers and adjust
1266          * needed_headroom if necessary.
1267          */
1268         max_headroom = LL_RESERVED_SPACE(dst->dev) + sizeof(struct ipv6hdr)
1269                         + dst->header_len + t->hlen;
1270         if (max_headroom > dev->needed_headroom)
1271                 dev->needed_headroom = max_headroom;
1272
1273         err = ip6_tnl_encap(skb, t, &proto, fl6);
1274         if (err)
1275                 return err;
1276
1277         if (encap_limit >= 0) {
1278                 init_tel_txopt(&opt, encap_limit);
1279                 ipv6_push_frag_opts(skb, &opt.ops, &proto);
1280         }
1281
1282         skb_push(skb, sizeof(struct ipv6hdr));
1283         skb_reset_network_header(skb);
1284         ipv6h = ipv6_hdr(skb);
1285         ip6_flow_hdr(ipv6h, dsfield,
1286                      ip6_make_flowlabel(net, skb, fl6->flowlabel, true, fl6));
1287         ipv6h->hop_limit = hop_limit;
1288         ipv6h->nexthdr = proto;
1289         ipv6h->saddr = fl6->saddr;
1290         ipv6h->daddr = fl6->daddr;
1291         ip6tunnel_xmit(NULL, skb, dev);
1292         return 0;
1293 tx_err_link_failure:
1294         stats->tx_carrier_errors++;
1295         dst_link_failure(skb);
1296 tx_err_dst_release:
1297         dst_release(dst);
1298         return err;
1299 }
1300 EXPORT_SYMBOL(ip6_tnl_xmit);
1301
1302 static inline int
1303 ipxip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev,
1304                 u8 protocol)
1305 {
1306         struct ip6_tnl *t = netdev_priv(dev);
1307         struct ipv6hdr *ipv6h;
1308         const struct iphdr  *iph;
1309         int encap_limit = -1;
1310         __u16 offset;
1311         struct flowi6 fl6;
1312         __u8 dsfield, orig_dsfield;
1313         __u32 mtu;
1314         u8 tproto;
1315         int err;
1316
1317         tproto = READ_ONCE(t->parms.proto);
1318         if (tproto != protocol && tproto != 0)
1319                 return -1;
1320
1321         if (t->parms.collect_md) {
1322                 struct ip_tunnel_info *tun_info;
1323                 const struct ip_tunnel_key *key;
1324
1325                 tun_info = skb_tunnel_info(skb);
1326                 if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) ||
1327                              ip_tunnel_info_af(tun_info) != AF_INET6))
1328                         return -1;
1329                 key = &tun_info->key;
1330                 memset(&fl6, 0, sizeof(fl6));
1331                 fl6.flowi6_proto = protocol;
1332                 fl6.saddr = key->u.ipv6.src;
1333                 fl6.daddr = key->u.ipv6.dst;
1334                 fl6.flowlabel = key->label;
1335                 dsfield =  key->tos;
1336                 switch (protocol) {
1337                 case IPPROTO_IPIP:
1338                         iph = ip_hdr(skb);
1339                         orig_dsfield = ipv4_get_dsfield(iph);
1340                         break;
1341                 case IPPROTO_IPV6:
1342                         ipv6h = ipv6_hdr(skb);
1343                         orig_dsfield = ipv6_get_dsfield(ipv6h);
1344                         break;
1345                 default:
1346                         orig_dsfield = dsfield;
1347                         break;
1348                 }
1349         } else {
1350                 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1351                         encap_limit = t->parms.encap_limit;
1352                 if (protocol == IPPROTO_IPV6) {
1353                         offset = ip6_tnl_parse_tlv_enc_lim(skb,
1354                                                 skb_network_header(skb));
1355                         /* ip6_tnl_parse_tlv_enc_lim() might have
1356                          * reallocated skb->head
1357                          */
1358                         if (offset > 0) {
1359                                 struct ipv6_tlv_tnl_enc_lim *tel;
1360
1361                                 tel = (void *)&skb_network_header(skb)[offset];
1362                                 if (tel->encap_limit == 0) {
1363                                         icmpv6_ndo_send(skb, ICMPV6_PARAMPROB,
1364                                                         ICMPV6_HDR_FIELD, offset + 2);
1365                                         return -1;
1366                                 }
1367                                 encap_limit = tel->encap_limit - 1;
1368                         }
1369                 }
1370
1371                 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
1372                 fl6.flowi6_proto = protocol;
1373
1374                 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
1375                         fl6.flowi6_mark = skb->mark;
1376                 else
1377                         fl6.flowi6_mark = t->parms.fwmark;
1378                 switch (protocol) {
1379                 case IPPROTO_IPIP:
1380                         iph = ip_hdr(skb);
1381                         orig_dsfield = ipv4_get_dsfield(iph);
1382                         if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
1383                                 dsfield = orig_dsfield;
1384                         else
1385                                 dsfield = ip6_tclass(t->parms.flowinfo);
1386                         break;
1387                 case IPPROTO_IPV6:
1388                         ipv6h = ipv6_hdr(skb);
1389                         orig_dsfield = ipv6_get_dsfield(ipv6h);
1390                         if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
1391                                 dsfield = orig_dsfield;
1392                         else
1393                                 dsfield = ip6_tclass(t->parms.flowinfo);
1394                         if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL)
1395                                 fl6.flowlabel |= ip6_flowlabel(ipv6h);
1396                         break;
1397                 default:
1398                         orig_dsfield = dsfield = ip6_tclass(t->parms.flowinfo);
1399                         break;
1400                 }
1401         }
1402
1403         fl6.flowi6_uid = sock_net_uid(dev_net(dev), NULL);
1404         dsfield = INET_ECN_encapsulate(dsfield, orig_dsfield);
1405
1406         if (iptunnel_handle_offloads(skb, SKB_GSO_IPXIP6))
1407                 return -1;
1408
1409         skb_set_inner_ipproto(skb, protocol);
1410
1411         err = ip6_tnl_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu,
1412                            protocol);
1413         if (err != 0) {
1414                 /* XXX: send ICMP error even if DF is not set. */
1415                 if (err == -EMSGSIZE)
1416                         switch (protocol) {
1417                         case IPPROTO_IPIP:
1418                                 icmp_ndo_send(skb, ICMP_DEST_UNREACH,
1419                                               ICMP_FRAG_NEEDED, htonl(mtu));
1420                                 break;
1421                         case IPPROTO_IPV6:
1422                                 icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
1423                                 break;
1424                         default:
1425                                 break;
1426                         }
1427                 return -1;
1428         }
1429
1430         return 0;
1431 }
1432
1433 static netdev_tx_t
1434 ip6_tnl_start_xmit(struct sk_buff *skb, struct net_device *dev)
1435 {
1436         struct ip6_tnl *t = netdev_priv(dev);
1437         struct net_device_stats *stats = &t->dev->stats;
1438         u8 ipproto;
1439         int ret;
1440
1441         if (!pskb_inet_may_pull(skb))
1442                 goto tx_err;
1443
1444         switch (skb->protocol) {
1445         case htons(ETH_P_IP):
1446                 ipproto = IPPROTO_IPIP;
1447                 break;
1448         case htons(ETH_P_IPV6):
1449                 if (ip6_tnl_addr_conflict(t, ipv6_hdr(skb)))
1450                         goto tx_err;
1451                 ipproto = IPPROTO_IPV6;
1452                 break;
1453         case htons(ETH_P_MPLS_UC):
1454                 ipproto = IPPROTO_MPLS;
1455                 break;
1456         default:
1457                 goto tx_err;
1458         }
1459
1460         ret = ipxip6_tnl_xmit(skb, dev, ipproto);
1461         if (ret < 0)
1462                 goto tx_err;
1463
1464         return NETDEV_TX_OK;
1465
1466 tx_err:
1467         stats->tx_errors++;
1468         stats->tx_dropped++;
1469         kfree_skb(skb);
1470         return NETDEV_TX_OK;
1471 }
1472
1473 static void ip6_tnl_link_config(struct ip6_tnl *t)
1474 {
1475         struct net_device *dev = t->dev;
1476         struct net_device *tdev = NULL;
1477         struct __ip6_tnl_parm *p = &t->parms;
1478         struct flowi6 *fl6 = &t->fl.u.ip6;
1479         int t_hlen;
1480         int mtu;
1481
1482         memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr));
1483         memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr));
1484
1485         /* Set up flowi template */
1486         fl6->saddr = p->laddr;
1487         fl6->daddr = p->raddr;
1488         fl6->flowi6_oif = p->link;
1489         fl6->flowlabel = 0;
1490
1491         if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS))
1492                 fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo;
1493         if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL))
1494                 fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo;
1495
1496         p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET);
1497         p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr);
1498
1499         if (p->flags&IP6_TNL_F_CAP_XMIT && p->flags&IP6_TNL_F_CAP_RCV)
1500                 dev->flags |= IFF_POINTOPOINT;
1501         else
1502                 dev->flags &= ~IFF_POINTOPOINT;
1503
1504         t->tun_hlen = 0;
1505         t->hlen = t->encap_hlen + t->tun_hlen;
1506         t_hlen = t->hlen + sizeof(struct ipv6hdr);
1507
1508         if (p->flags & IP6_TNL_F_CAP_XMIT) {
1509                 int strict = (ipv6_addr_type(&p->raddr) &
1510                               (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL));
1511
1512                 struct rt6_info *rt = rt6_lookup(t->net,
1513                                                  &p->raddr, &p->laddr,
1514                                                  p->link, NULL, strict);
1515                 if (rt) {
1516                         tdev = rt->dst.dev;
1517                         ip6_rt_put(rt);
1518                 }
1519
1520                 if (!tdev && p->link)
1521                         tdev = __dev_get_by_index(t->net, p->link);
1522
1523                 if (tdev) {
1524                         dev->hard_header_len = tdev->hard_header_len + t_hlen;
1525                         mtu = min_t(unsigned int, tdev->mtu, IP6_MAX_MTU);
1526
1527                         mtu = mtu - t_hlen;
1528                         if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1529                                 mtu -= 8;
1530
1531                         if (mtu < IPV6_MIN_MTU)
1532                                 mtu = IPV6_MIN_MTU;
1533                         WRITE_ONCE(dev->mtu, mtu);
1534                 }
1535         }
1536 }
1537
1538 /**
1539  * ip6_tnl_change - update the tunnel parameters
1540  *   @t: tunnel to be changed
1541  *   @p: tunnel configuration parameters
1542  *
1543  * Description:
1544  *   ip6_tnl_change() updates the tunnel parameters
1545  **/
1546
1547 static int
1548 ip6_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p)
1549 {
1550         t->parms.laddr = p->laddr;
1551         t->parms.raddr = p->raddr;
1552         t->parms.flags = p->flags;
1553         t->parms.hop_limit = p->hop_limit;
1554         t->parms.encap_limit = p->encap_limit;
1555         t->parms.flowinfo = p->flowinfo;
1556         t->parms.link = p->link;
1557         t->parms.proto = p->proto;
1558         t->parms.fwmark = p->fwmark;
1559         dst_cache_reset(&t->dst_cache);
1560         ip6_tnl_link_config(t);
1561         return 0;
1562 }
1563
1564 static int ip6_tnl_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p)
1565 {
1566         struct net *net = t->net;
1567         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1568         int err;
1569
1570         ip6_tnl_unlink(ip6n, t);
1571         synchronize_net();
1572         err = ip6_tnl_change(t, p);
1573         ip6_tnl_link(ip6n, t);
1574         netdev_state_change(t->dev);
1575         return err;
1576 }
1577
1578 static int ip6_tnl0_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p)
1579 {
1580         /* for default tnl0 device allow to change only the proto */
1581         t->parms.proto = p->proto;
1582         netdev_state_change(t->dev);
1583         return 0;
1584 }
1585
1586 static void
1587 ip6_tnl_parm_from_user(struct __ip6_tnl_parm *p, const struct ip6_tnl_parm *u)
1588 {
1589         p->laddr = u->laddr;
1590         p->raddr = u->raddr;
1591         p->flags = u->flags;
1592         p->hop_limit = u->hop_limit;
1593         p->encap_limit = u->encap_limit;
1594         p->flowinfo = u->flowinfo;
1595         p->link = u->link;
1596         p->proto = u->proto;
1597         memcpy(p->name, u->name, sizeof(u->name));
1598 }
1599
1600 static void
1601 ip6_tnl_parm_to_user(struct ip6_tnl_parm *u, const struct __ip6_tnl_parm *p)
1602 {
1603         u->laddr = p->laddr;
1604         u->raddr = p->raddr;
1605         u->flags = p->flags;
1606         u->hop_limit = p->hop_limit;
1607         u->encap_limit = p->encap_limit;
1608         u->flowinfo = p->flowinfo;
1609         u->link = p->link;
1610         u->proto = p->proto;
1611         memcpy(u->name, p->name, sizeof(u->name));
1612 }
1613
1614 /**
1615  * ip6_tnl_ioctl - configure ipv6 tunnels from userspace
1616  *   @dev: virtual device associated with tunnel
1617  *   @ifr: parameters passed from userspace
1618  *   @cmd: command to be performed
1619  *
1620  * Description:
1621  *   ip6_tnl_ioctl() is used for managing IPv6 tunnels
1622  *   from userspace.
1623  *
1624  *   The possible commands are the following:
1625  *     %SIOCGETTUNNEL: get tunnel parameters for device
1626  *     %SIOCADDTUNNEL: add tunnel matching given tunnel parameters
1627  *     %SIOCCHGTUNNEL: change tunnel parameters to those given
1628  *     %SIOCDELTUNNEL: delete tunnel
1629  *
1630  *   The fallback device "ip6tnl0", created during module
1631  *   initialization, can be used for creating other tunnel devices.
1632  *
1633  * Return:
1634  *   0 on success,
1635  *   %-EFAULT if unable to copy data to or from userspace,
1636  *   %-EPERM if current process hasn't %CAP_NET_ADMIN set
1637  *   %-EINVAL if passed tunnel parameters are invalid,
1638  *   %-EEXIST if changing a tunnel's parameters would cause a conflict
1639  *   %-ENODEV if attempting to change or delete a nonexisting device
1640  **/
1641
1642 static int
1643 ip6_tnl_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
1644 {
1645         int err = 0;
1646         struct ip6_tnl_parm p;
1647         struct __ip6_tnl_parm p1;
1648         struct ip6_tnl *t = netdev_priv(dev);
1649         struct net *net = t->net;
1650         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1651
1652         memset(&p1, 0, sizeof(p1));
1653
1654         switch (cmd) {
1655         case SIOCGETTUNNEL:
1656                 if (dev == ip6n->fb_tnl_dev) {
1657                         if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
1658                                 err = -EFAULT;
1659                                 break;
1660                         }
1661                         ip6_tnl_parm_from_user(&p1, &p);
1662                         t = ip6_tnl_locate(net, &p1, 0);
1663                         if (IS_ERR(t))
1664                                 t = netdev_priv(dev);
1665                 } else {
1666                         memset(&p, 0, sizeof(p));
1667                 }
1668                 ip6_tnl_parm_to_user(&p, &t->parms);
1669                 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) {
1670                         err = -EFAULT;
1671                 }
1672                 break;
1673         case SIOCADDTUNNEL:
1674         case SIOCCHGTUNNEL:
1675                 err = -EPERM;
1676                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1677                         break;
1678                 err = -EFAULT;
1679                 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
1680                         break;
1681                 err = -EINVAL;
1682                 if (p.proto != IPPROTO_IPV6 && p.proto != IPPROTO_IPIP &&
1683                     p.proto != 0)
1684                         break;
1685                 ip6_tnl_parm_from_user(&p1, &p);
1686                 t = ip6_tnl_locate(net, &p1, cmd == SIOCADDTUNNEL);
1687                 if (cmd == SIOCCHGTUNNEL) {
1688                         if (!IS_ERR(t)) {
1689                                 if (t->dev != dev) {
1690                                         err = -EEXIST;
1691                                         break;
1692                                 }
1693                         } else
1694                                 t = netdev_priv(dev);
1695                         if (dev == ip6n->fb_tnl_dev)
1696                                 err = ip6_tnl0_update(t, &p1);
1697                         else
1698                                 err = ip6_tnl_update(t, &p1);
1699                 }
1700                 if (!IS_ERR(t)) {
1701                         err = 0;
1702                         ip6_tnl_parm_to_user(&p, &t->parms);
1703                         if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
1704                                 err = -EFAULT;
1705
1706                 } else {
1707                         err = PTR_ERR(t);
1708                 }
1709                 break;
1710         case SIOCDELTUNNEL:
1711                 err = -EPERM;
1712                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1713                         break;
1714
1715                 if (dev == ip6n->fb_tnl_dev) {
1716                         err = -EFAULT;
1717                         if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
1718                                 break;
1719                         err = -ENOENT;
1720                         ip6_tnl_parm_from_user(&p1, &p);
1721                         t = ip6_tnl_locate(net, &p1, 0);
1722                         if (IS_ERR(t))
1723                                 break;
1724                         err = -EPERM;
1725                         if (t->dev == ip6n->fb_tnl_dev)
1726                                 break;
1727                         dev = t->dev;
1728                 }
1729                 err = 0;
1730                 unregister_netdevice(dev);
1731                 break;
1732         default:
1733                 err = -EINVAL;
1734         }
1735         return err;
1736 }
1737
1738 /**
1739  * ip6_tnl_change_mtu - change mtu manually for tunnel device
1740  *   @dev: virtual device associated with tunnel
1741  *   @new_mtu: the new mtu
1742  *
1743  * Return:
1744  *   0 on success,
1745  *   %-EINVAL if mtu too small
1746  **/
1747
1748 int ip6_tnl_change_mtu(struct net_device *dev, int new_mtu)
1749 {
1750         struct ip6_tnl *tnl = netdev_priv(dev);
1751
1752         if (tnl->parms.proto == IPPROTO_IPV6) {
1753                 if (new_mtu < IPV6_MIN_MTU)
1754                         return -EINVAL;
1755         } else {
1756                 if (new_mtu < ETH_MIN_MTU)
1757                         return -EINVAL;
1758         }
1759         if (tnl->parms.proto == IPPROTO_IPV6 || tnl->parms.proto == 0) {
1760                 if (new_mtu > IP6_MAX_MTU - dev->hard_header_len)
1761                         return -EINVAL;
1762         } else {
1763                 if (new_mtu > IP_MAX_MTU - dev->hard_header_len)
1764                         return -EINVAL;
1765         }
1766         dev->mtu = new_mtu;
1767         return 0;
1768 }
1769 EXPORT_SYMBOL(ip6_tnl_change_mtu);
1770
1771 int ip6_tnl_get_iflink(const struct net_device *dev)
1772 {
1773         struct ip6_tnl *t = netdev_priv(dev);
1774
1775         return t->parms.link;
1776 }
1777 EXPORT_SYMBOL(ip6_tnl_get_iflink);
1778
1779 int ip6_tnl_encap_add_ops(const struct ip6_tnl_encap_ops *ops,
1780                           unsigned int num)
1781 {
1782         if (num >= MAX_IPTUN_ENCAP_OPS)
1783                 return -ERANGE;
1784
1785         return !cmpxchg((const struct ip6_tnl_encap_ops **)
1786                         &ip6tun_encaps[num],
1787                         NULL, ops) ? 0 : -1;
1788 }
1789 EXPORT_SYMBOL(ip6_tnl_encap_add_ops);
1790
1791 int ip6_tnl_encap_del_ops(const struct ip6_tnl_encap_ops *ops,
1792                           unsigned int num)
1793 {
1794         int ret;
1795
1796         if (num >= MAX_IPTUN_ENCAP_OPS)
1797                 return -ERANGE;
1798
1799         ret = (cmpxchg((const struct ip6_tnl_encap_ops **)
1800                        &ip6tun_encaps[num],
1801                        ops, NULL) == ops) ? 0 : -1;
1802
1803         synchronize_net();
1804
1805         return ret;
1806 }
1807 EXPORT_SYMBOL(ip6_tnl_encap_del_ops);
1808
1809 int ip6_tnl_encap_setup(struct ip6_tnl *t,
1810                         struct ip_tunnel_encap *ipencap)
1811 {
1812         int hlen;
1813
1814         memset(&t->encap, 0, sizeof(t->encap));
1815
1816         hlen = ip6_encap_hlen(ipencap);
1817         if (hlen < 0)
1818                 return hlen;
1819
1820         t->encap.type = ipencap->type;
1821         t->encap.sport = ipencap->sport;
1822         t->encap.dport = ipencap->dport;
1823         t->encap.flags = ipencap->flags;
1824
1825         t->encap_hlen = hlen;
1826         t->hlen = t->encap_hlen + t->tun_hlen;
1827
1828         return 0;
1829 }
1830 EXPORT_SYMBOL_GPL(ip6_tnl_encap_setup);
1831
1832 static const struct net_device_ops ip6_tnl_netdev_ops = {
1833         .ndo_init       = ip6_tnl_dev_init,
1834         .ndo_uninit     = ip6_tnl_dev_uninit,
1835         .ndo_start_xmit = ip6_tnl_start_xmit,
1836         .ndo_do_ioctl   = ip6_tnl_ioctl,
1837         .ndo_change_mtu = ip6_tnl_change_mtu,
1838         .ndo_get_stats  = ip6_get_stats,
1839         .ndo_get_iflink = ip6_tnl_get_iflink,
1840 };
1841
1842 #define IPXIPX_FEATURES (NETIF_F_SG |           \
1843                          NETIF_F_FRAGLIST |     \
1844                          NETIF_F_HIGHDMA |      \
1845                          NETIF_F_GSO_SOFTWARE | \
1846                          NETIF_F_HW_CSUM)
1847
1848 /**
1849  * ip6_tnl_dev_setup - setup virtual tunnel device
1850  *   @dev: virtual device associated with tunnel
1851  *
1852  * Description:
1853  *   Initialize function pointers and device parameters
1854  **/
1855
1856 static void ip6_tnl_dev_setup(struct net_device *dev)
1857 {
1858         dev->netdev_ops = &ip6_tnl_netdev_ops;
1859         dev->header_ops = &ip_tunnel_header_ops;
1860         dev->needs_free_netdev = true;
1861         dev->priv_destructor = ip6_dev_free;
1862
1863         dev->type = ARPHRD_TUNNEL6;
1864         dev->flags |= IFF_NOARP;
1865         dev->addr_len = sizeof(struct in6_addr);
1866         dev->features |= NETIF_F_LLTX;
1867         netif_keep_dst(dev);
1868
1869         dev->features           |= IPXIPX_FEATURES;
1870         dev->hw_features        |= IPXIPX_FEATURES;
1871
1872         /* This perm addr will be used as interface identifier by IPv6 */
1873         dev->addr_assign_type = NET_ADDR_RANDOM;
1874         eth_random_addr(dev->perm_addr);
1875 }
1876
1877
1878 /**
1879  * ip6_tnl_dev_init_gen - general initializer for all tunnel devices
1880  *   @dev: virtual device associated with tunnel
1881  **/
1882
1883 static inline int
1884 ip6_tnl_dev_init_gen(struct net_device *dev)
1885 {
1886         struct ip6_tnl *t = netdev_priv(dev);
1887         int ret;
1888         int t_hlen;
1889
1890         t->dev = dev;
1891         t->net = dev_net(dev);
1892         dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1893         if (!dev->tstats)
1894                 return -ENOMEM;
1895
1896         ret = dst_cache_init(&t->dst_cache, GFP_KERNEL);
1897         if (ret)
1898                 goto free_stats;
1899
1900         ret = gro_cells_init(&t->gro_cells, dev);
1901         if (ret)
1902                 goto destroy_dst;
1903
1904         t->tun_hlen = 0;
1905         t->hlen = t->encap_hlen + t->tun_hlen;
1906         t_hlen = t->hlen + sizeof(struct ipv6hdr);
1907
1908         dev->type = ARPHRD_TUNNEL6;
1909         dev->hard_header_len = LL_MAX_HEADER + t_hlen;
1910         dev->mtu = ETH_DATA_LEN - t_hlen;
1911         if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1912                 dev->mtu -= 8;
1913         dev->min_mtu = ETH_MIN_MTU;
1914         dev->max_mtu = IP6_MAX_MTU - dev->hard_header_len;
1915
1916         dev_hold(dev);
1917         return 0;
1918
1919 destroy_dst:
1920         dst_cache_destroy(&t->dst_cache);
1921 free_stats:
1922         free_percpu(dev->tstats);
1923         dev->tstats = NULL;
1924
1925         return ret;
1926 }
1927
1928 /**
1929  * ip6_tnl_dev_init - initializer for all non fallback tunnel devices
1930  *   @dev: virtual device associated with tunnel
1931  **/
1932
1933 static int ip6_tnl_dev_init(struct net_device *dev)
1934 {
1935         struct ip6_tnl *t = netdev_priv(dev);
1936         int err = ip6_tnl_dev_init_gen(dev);
1937
1938         if (err)
1939                 return err;
1940         ip6_tnl_link_config(t);
1941         if (t->parms.collect_md)
1942                 netif_keep_dst(dev);
1943         return 0;
1944 }
1945
1946 /**
1947  * ip6_fb_tnl_dev_init - initializer for fallback tunnel device
1948  *   @dev: fallback device
1949  *
1950  * Return: 0
1951  **/
1952
1953 static int __net_init ip6_fb_tnl_dev_init(struct net_device *dev)
1954 {
1955         struct ip6_tnl *t = netdev_priv(dev);
1956         struct net *net = dev_net(dev);
1957         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1958
1959         t->parms.proto = IPPROTO_IPV6;
1960
1961         rcu_assign_pointer(ip6n->tnls_wc[0], t);
1962         return 0;
1963 }
1964
1965 static int ip6_tnl_validate(struct nlattr *tb[], struct nlattr *data[],
1966                             struct netlink_ext_ack *extack)
1967 {
1968         u8 proto;
1969
1970         if (!data || !data[IFLA_IPTUN_PROTO])
1971                 return 0;
1972
1973         proto = nla_get_u8(data[IFLA_IPTUN_PROTO]);
1974         if (proto != IPPROTO_IPV6 &&
1975             proto != IPPROTO_IPIP &&
1976             proto != 0)
1977                 return -EINVAL;
1978
1979         return 0;
1980 }
1981
1982 static void ip6_tnl_netlink_parms(struct nlattr *data[],
1983                                   struct __ip6_tnl_parm *parms)
1984 {
1985         memset(parms, 0, sizeof(*parms));
1986
1987         if (!data)
1988                 return;
1989
1990         if (data[IFLA_IPTUN_LINK])
1991                 parms->link = nla_get_u32(data[IFLA_IPTUN_LINK]);
1992
1993         if (data[IFLA_IPTUN_LOCAL])
1994                 parms->laddr = nla_get_in6_addr(data[IFLA_IPTUN_LOCAL]);
1995
1996         if (data[IFLA_IPTUN_REMOTE])
1997                 parms->raddr = nla_get_in6_addr(data[IFLA_IPTUN_REMOTE]);
1998
1999         if (data[IFLA_IPTUN_TTL])
2000                 parms->hop_limit = nla_get_u8(data[IFLA_IPTUN_TTL]);
2001
2002         if (data[IFLA_IPTUN_ENCAP_LIMIT])
2003                 parms->encap_limit = nla_get_u8(data[IFLA_IPTUN_ENCAP_LIMIT]);
2004
2005         if (data[IFLA_IPTUN_FLOWINFO])
2006                 parms->flowinfo = nla_get_be32(data[IFLA_IPTUN_FLOWINFO]);
2007
2008         if (data[IFLA_IPTUN_FLAGS])
2009                 parms->flags = nla_get_u32(data[IFLA_IPTUN_FLAGS]);
2010
2011         if (data[IFLA_IPTUN_PROTO])
2012                 parms->proto = nla_get_u8(data[IFLA_IPTUN_PROTO]);
2013
2014         if (data[IFLA_IPTUN_COLLECT_METADATA])
2015                 parms->collect_md = true;
2016
2017         if (data[IFLA_IPTUN_FWMARK])
2018                 parms->fwmark = nla_get_u32(data[IFLA_IPTUN_FWMARK]);
2019 }
2020
2021 static bool ip6_tnl_netlink_encap_parms(struct nlattr *data[],
2022                                         struct ip_tunnel_encap *ipencap)
2023 {
2024         bool ret = false;
2025
2026         memset(ipencap, 0, sizeof(*ipencap));
2027
2028         if (!data)
2029                 return ret;
2030
2031         if (data[IFLA_IPTUN_ENCAP_TYPE]) {
2032                 ret = true;
2033                 ipencap->type = nla_get_u16(data[IFLA_IPTUN_ENCAP_TYPE]);
2034         }
2035
2036         if (data[IFLA_IPTUN_ENCAP_FLAGS]) {
2037                 ret = true;
2038                 ipencap->flags = nla_get_u16(data[IFLA_IPTUN_ENCAP_FLAGS]);
2039         }
2040
2041         if (data[IFLA_IPTUN_ENCAP_SPORT]) {
2042                 ret = true;
2043                 ipencap->sport = nla_get_be16(data[IFLA_IPTUN_ENCAP_SPORT]);
2044         }
2045
2046         if (data[IFLA_IPTUN_ENCAP_DPORT]) {
2047                 ret = true;
2048                 ipencap->dport = nla_get_be16(data[IFLA_IPTUN_ENCAP_DPORT]);
2049         }
2050
2051         return ret;
2052 }
2053
2054 static int ip6_tnl_newlink(struct net *src_net, struct net_device *dev,
2055                            struct nlattr *tb[], struct nlattr *data[],
2056                            struct netlink_ext_ack *extack)
2057 {
2058         struct net *net = dev_net(dev);
2059         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
2060         struct ip_tunnel_encap ipencap;
2061         struct ip6_tnl *nt, *t;
2062         int err;
2063
2064         nt = netdev_priv(dev);
2065
2066         if (ip6_tnl_netlink_encap_parms(data, &ipencap)) {
2067                 err = ip6_tnl_encap_setup(nt, &ipencap);
2068                 if (err < 0)
2069                         return err;
2070         }
2071
2072         ip6_tnl_netlink_parms(data, &nt->parms);
2073
2074         if (nt->parms.collect_md) {
2075                 if (rtnl_dereference(ip6n->collect_md_tun))
2076                         return -EEXIST;
2077         } else {
2078                 t = ip6_tnl_locate(net, &nt->parms, 0);
2079                 if (!IS_ERR(t))
2080                         return -EEXIST;
2081         }
2082
2083         err = ip6_tnl_create2(dev);
2084         if (!err && tb[IFLA_MTU])
2085                 ip6_tnl_change_mtu(dev, nla_get_u32(tb[IFLA_MTU]));
2086
2087         return err;
2088 }
2089
2090 static int ip6_tnl_changelink(struct net_device *dev, struct nlattr *tb[],
2091                               struct nlattr *data[],
2092                               struct netlink_ext_ack *extack)
2093 {
2094         struct ip6_tnl *t = netdev_priv(dev);
2095         struct __ip6_tnl_parm p;
2096         struct net *net = t->net;
2097         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
2098         struct ip_tunnel_encap ipencap;
2099
2100         if (dev == ip6n->fb_tnl_dev)
2101                 return -EINVAL;
2102
2103         if (ip6_tnl_netlink_encap_parms(data, &ipencap)) {
2104                 int err = ip6_tnl_encap_setup(t, &ipencap);
2105
2106                 if (err < 0)
2107                         return err;
2108         }
2109         ip6_tnl_netlink_parms(data, &p);
2110         if (p.collect_md)
2111                 return -EINVAL;
2112
2113         t = ip6_tnl_locate(net, &p, 0);
2114         if (!IS_ERR(t)) {
2115                 if (t->dev != dev)
2116                         return -EEXIST;
2117         } else
2118                 t = netdev_priv(dev);
2119
2120         return ip6_tnl_update(t, &p);
2121 }
2122
2123 static void ip6_tnl_dellink(struct net_device *dev, struct list_head *head)
2124 {
2125         struct net *net = dev_net(dev);
2126         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
2127
2128         if (dev != ip6n->fb_tnl_dev)
2129                 unregister_netdevice_queue(dev, head);
2130 }
2131
2132 static size_t ip6_tnl_get_size(const struct net_device *dev)
2133 {
2134         return
2135                 /* IFLA_IPTUN_LINK */
2136                 nla_total_size(4) +
2137                 /* IFLA_IPTUN_LOCAL */
2138                 nla_total_size(sizeof(struct in6_addr)) +
2139                 /* IFLA_IPTUN_REMOTE */
2140                 nla_total_size(sizeof(struct in6_addr)) +
2141                 /* IFLA_IPTUN_TTL */
2142                 nla_total_size(1) +
2143                 /* IFLA_IPTUN_ENCAP_LIMIT */
2144                 nla_total_size(1) +
2145                 /* IFLA_IPTUN_FLOWINFO */
2146                 nla_total_size(4) +
2147                 /* IFLA_IPTUN_FLAGS */
2148                 nla_total_size(4) +
2149                 /* IFLA_IPTUN_PROTO */
2150                 nla_total_size(1) +
2151                 /* IFLA_IPTUN_ENCAP_TYPE */
2152                 nla_total_size(2) +
2153                 /* IFLA_IPTUN_ENCAP_FLAGS */
2154                 nla_total_size(2) +
2155                 /* IFLA_IPTUN_ENCAP_SPORT */
2156                 nla_total_size(2) +
2157                 /* IFLA_IPTUN_ENCAP_DPORT */
2158                 nla_total_size(2) +
2159                 /* IFLA_IPTUN_COLLECT_METADATA */
2160                 nla_total_size(0) +
2161                 /* IFLA_IPTUN_FWMARK */
2162                 nla_total_size(4) +
2163                 0;
2164 }
2165
2166 static int ip6_tnl_fill_info(struct sk_buff *skb, const struct net_device *dev)
2167 {
2168         struct ip6_tnl *tunnel = netdev_priv(dev);
2169         struct __ip6_tnl_parm *parm = &tunnel->parms;
2170
2171         if (nla_put_u32(skb, IFLA_IPTUN_LINK, parm->link) ||
2172             nla_put_in6_addr(skb, IFLA_IPTUN_LOCAL, &parm->laddr) ||
2173             nla_put_in6_addr(skb, IFLA_IPTUN_REMOTE, &parm->raddr) ||
2174             nla_put_u8(skb, IFLA_IPTUN_TTL, parm->hop_limit) ||
2175             nla_put_u8(skb, IFLA_IPTUN_ENCAP_LIMIT, parm->encap_limit) ||
2176             nla_put_be32(skb, IFLA_IPTUN_FLOWINFO, parm->flowinfo) ||
2177             nla_put_u32(skb, IFLA_IPTUN_FLAGS, parm->flags) ||
2178             nla_put_u8(skb, IFLA_IPTUN_PROTO, parm->proto) ||
2179             nla_put_u32(skb, IFLA_IPTUN_FWMARK, parm->fwmark))
2180                 goto nla_put_failure;
2181
2182         if (nla_put_u16(skb, IFLA_IPTUN_ENCAP_TYPE, tunnel->encap.type) ||
2183             nla_put_be16(skb, IFLA_IPTUN_ENCAP_SPORT, tunnel->encap.sport) ||
2184             nla_put_be16(skb, IFLA_IPTUN_ENCAP_DPORT, tunnel->encap.dport) ||
2185             nla_put_u16(skb, IFLA_IPTUN_ENCAP_FLAGS, tunnel->encap.flags))
2186                 goto nla_put_failure;
2187
2188         if (parm->collect_md)
2189                 if (nla_put_flag(skb, IFLA_IPTUN_COLLECT_METADATA))
2190                         goto nla_put_failure;
2191
2192         return 0;
2193
2194 nla_put_failure:
2195         return -EMSGSIZE;
2196 }
2197
2198 struct net *ip6_tnl_get_link_net(const struct net_device *dev)
2199 {
2200         struct ip6_tnl *tunnel = netdev_priv(dev);
2201
2202         return tunnel->net;
2203 }
2204 EXPORT_SYMBOL(ip6_tnl_get_link_net);
2205
2206 static const struct nla_policy ip6_tnl_policy[IFLA_IPTUN_MAX + 1] = {
2207         [IFLA_IPTUN_LINK]               = { .type = NLA_U32 },
2208         [IFLA_IPTUN_LOCAL]              = { .len = sizeof(struct in6_addr) },
2209         [IFLA_IPTUN_REMOTE]             = { .len = sizeof(struct in6_addr) },
2210         [IFLA_IPTUN_TTL]                = { .type = NLA_U8 },
2211         [IFLA_IPTUN_ENCAP_LIMIT]        = { .type = NLA_U8 },
2212         [IFLA_IPTUN_FLOWINFO]           = { .type = NLA_U32 },
2213         [IFLA_IPTUN_FLAGS]              = { .type = NLA_U32 },
2214         [IFLA_IPTUN_PROTO]              = { .type = NLA_U8 },
2215         [IFLA_IPTUN_ENCAP_TYPE]         = { .type = NLA_U16 },
2216         [IFLA_IPTUN_ENCAP_FLAGS]        = { .type = NLA_U16 },
2217         [IFLA_IPTUN_ENCAP_SPORT]        = { .type = NLA_U16 },
2218         [IFLA_IPTUN_ENCAP_DPORT]        = { .type = NLA_U16 },
2219         [IFLA_IPTUN_COLLECT_METADATA]   = { .type = NLA_FLAG },
2220         [IFLA_IPTUN_FWMARK]             = { .type = NLA_U32 },
2221 };
2222
2223 static struct rtnl_link_ops ip6_link_ops __read_mostly = {
2224         .kind           = "ip6tnl",
2225         .maxtype        = IFLA_IPTUN_MAX,
2226         .policy         = ip6_tnl_policy,
2227         .priv_size      = sizeof(struct ip6_tnl),
2228         .setup          = ip6_tnl_dev_setup,
2229         .validate       = ip6_tnl_validate,
2230         .newlink        = ip6_tnl_newlink,
2231         .changelink     = ip6_tnl_changelink,
2232         .dellink        = ip6_tnl_dellink,
2233         .get_size       = ip6_tnl_get_size,
2234         .fill_info      = ip6_tnl_fill_info,
2235         .get_link_net   = ip6_tnl_get_link_net,
2236 };
2237
2238 static struct xfrm6_tunnel ip4ip6_handler __read_mostly = {
2239         .handler        = ip4ip6_rcv,
2240         .err_handler    = ip4ip6_err,
2241         .priority       =       1,
2242 };
2243
2244 static struct xfrm6_tunnel ip6ip6_handler __read_mostly = {
2245         .handler        = ip6ip6_rcv,
2246         .err_handler    = ip6ip6_err,
2247         .priority       =       1,
2248 };
2249
2250 static struct xfrm6_tunnel mplsip6_handler __read_mostly = {
2251         .handler        = mplsip6_rcv,
2252         .err_handler    = mplsip6_err,
2253         .priority       =       1,
2254 };
2255
2256 static void __net_exit ip6_tnl_destroy_tunnels(struct net *net, struct list_head *list)
2257 {
2258         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
2259         struct net_device *dev, *aux;
2260         int h;
2261         struct ip6_tnl *t;
2262
2263         for_each_netdev_safe(net, dev, aux)
2264                 if (dev->rtnl_link_ops == &ip6_link_ops)
2265                         unregister_netdevice_queue(dev, list);
2266
2267         for (h = 0; h < IP6_TUNNEL_HASH_SIZE; h++) {
2268                 t = rtnl_dereference(ip6n->tnls_r_l[h]);
2269                 while (t) {
2270                         /* If dev is in the same netns, it has already
2271                          * been added to the list by the previous loop.
2272                          */
2273                         if (!net_eq(dev_net(t->dev), net))
2274                                 unregister_netdevice_queue(t->dev, list);
2275                         t = rtnl_dereference(t->next);
2276                 }
2277         }
2278
2279         t = rtnl_dereference(ip6n->tnls_wc[0]);
2280         while (t) {
2281                 /* If dev is in the same netns, it has already
2282                  * been added to the list by the previous loop.
2283                  */
2284                 if (!net_eq(dev_net(t->dev), net))
2285                         unregister_netdevice_queue(t->dev, list);
2286                 t = rtnl_dereference(t->next);
2287         }
2288 }
2289
2290 static int __net_init ip6_tnl_init_net(struct net *net)
2291 {
2292         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
2293         struct ip6_tnl *t = NULL;
2294         int err;
2295
2296         ip6n->tnls[0] = ip6n->tnls_wc;
2297         ip6n->tnls[1] = ip6n->tnls_r_l;
2298
2299         if (!net_has_fallback_tunnels(net))
2300                 return 0;
2301         err = -ENOMEM;
2302         ip6n->fb_tnl_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6tnl0",
2303                                         NET_NAME_UNKNOWN, ip6_tnl_dev_setup);
2304
2305         if (!ip6n->fb_tnl_dev)
2306                 goto err_alloc_dev;
2307         dev_net_set(ip6n->fb_tnl_dev, net);
2308         ip6n->fb_tnl_dev->rtnl_link_ops = &ip6_link_ops;
2309         /* FB netdevice is special: we have one, and only one per netns.
2310          * Allowing to move it to another netns is clearly unsafe.
2311          */
2312         ip6n->fb_tnl_dev->features |= NETIF_F_NETNS_LOCAL;
2313
2314         err = ip6_fb_tnl_dev_init(ip6n->fb_tnl_dev);
2315         if (err < 0)
2316                 goto err_register;
2317
2318         err = register_netdev(ip6n->fb_tnl_dev);
2319         if (err < 0)
2320                 goto err_register;
2321
2322         t = netdev_priv(ip6n->fb_tnl_dev);
2323
2324         strcpy(t->parms.name, ip6n->fb_tnl_dev->name);
2325         return 0;
2326
2327 err_register:
2328         free_netdev(ip6n->fb_tnl_dev);
2329 err_alloc_dev:
2330         return err;
2331 }
2332
2333 static void __net_exit ip6_tnl_exit_batch_net(struct list_head *net_list)
2334 {
2335         struct net *net;
2336         LIST_HEAD(list);
2337
2338         rtnl_lock();
2339         list_for_each_entry(net, net_list, exit_list)
2340                 ip6_tnl_destroy_tunnels(net, &list);
2341         unregister_netdevice_many(&list);
2342         rtnl_unlock();
2343 }
2344
2345 static struct pernet_operations ip6_tnl_net_ops = {
2346         .init = ip6_tnl_init_net,
2347         .exit_batch = ip6_tnl_exit_batch_net,
2348         .id   = &ip6_tnl_net_id,
2349         .size = sizeof(struct ip6_tnl_net),
2350 };
2351
2352 /**
2353  * ip6_tunnel_init - register protocol and reserve needed resources
2354  *
2355  * Return: 0 on success
2356  **/
2357
2358 static int __init ip6_tunnel_init(void)
2359 {
2360         int  err;
2361
2362         if (!ipv6_mod_enabled())
2363                 return -EOPNOTSUPP;
2364
2365         err = register_pernet_device(&ip6_tnl_net_ops);
2366         if (err < 0)
2367                 goto out_pernet;
2368
2369         err = xfrm6_tunnel_register(&ip4ip6_handler, AF_INET);
2370         if (err < 0) {
2371                 pr_err("%s: can't register ip4ip6\n", __func__);
2372                 goto out_ip4ip6;
2373         }
2374
2375         err = xfrm6_tunnel_register(&ip6ip6_handler, AF_INET6);
2376         if (err < 0) {
2377                 pr_err("%s: can't register ip6ip6\n", __func__);
2378                 goto out_ip6ip6;
2379         }
2380
2381         if (ip6_tnl_mpls_supported()) {
2382                 err = xfrm6_tunnel_register(&mplsip6_handler, AF_MPLS);
2383                 if (err < 0) {
2384                         pr_err("%s: can't register mplsip6\n", __func__);
2385                         goto out_mplsip6;
2386                 }
2387         }
2388
2389         err = rtnl_link_register(&ip6_link_ops);
2390         if (err < 0)
2391                 goto rtnl_link_failed;
2392
2393         return 0;
2394
2395 rtnl_link_failed:
2396         if (ip6_tnl_mpls_supported())
2397                 xfrm6_tunnel_deregister(&mplsip6_handler, AF_MPLS);
2398 out_mplsip6:
2399         xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6);
2400 out_ip6ip6:
2401         xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET);
2402 out_ip4ip6:
2403         unregister_pernet_device(&ip6_tnl_net_ops);
2404 out_pernet:
2405         return err;
2406 }
2407
2408 /**
2409  * ip6_tunnel_cleanup - free resources and unregister protocol
2410  **/
2411
2412 static void __exit ip6_tunnel_cleanup(void)
2413 {
2414         rtnl_link_unregister(&ip6_link_ops);
2415         if (xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET))
2416                 pr_info("%s: can't deregister ip4ip6\n", __func__);
2417
2418         if (xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6))
2419                 pr_info("%s: can't deregister ip6ip6\n", __func__);
2420
2421         if (ip6_tnl_mpls_supported() &&
2422             xfrm6_tunnel_deregister(&mplsip6_handler, AF_MPLS))
2423                 pr_info("%s: can't deregister mplsip6\n", __func__);
2424         unregister_pernet_device(&ip6_tnl_net_ops);
2425 }
2426
2427 module_init(ip6_tunnel_init);
2428 module_exit(ip6_tunnel_cleanup);