net/ipv6/ip6_tunnel.c

   1 /*
   2  *      IPv6 tunneling device
   3  *      Linux INET6 implementation
   4  *
   5  *      Authors:
   6  *      Ville Nuorvala          <vnuorval@tcs.hut.fi>
   7  *      Yasuyuki Kozakai        <kozakai@linux-ipv6.org>
   8  *
   9  *      Based on:
  10  *      linux/net/ipv6/sit.c and linux/net/ipv4/ipip.c
  11  *
  12  *      RFC 2473
  13  *
  14  *      This program is free software; you can redistribute it and/or
  15  *      modify it under the terms of the GNU General Public License
  16  *      as published by the Free Software Foundation; either version
  17  *      2 of the License, or (at your option) any later version.
  18  *
  19  */
  20
  21 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  22
  23 #include <linux/module.h>
  24 #include <linux/capability.h>
  25 #include <linux/errno.h>
  26 #include <linux/types.h>
  27 #include <linux/sockios.h>
  28 #include <linux/icmp.h>
  29 #include <linux/if.h>
  30 #include <linux/in.h>
  31 #include <linux/ip.h>
  32 #include <linux/net.h>
  33 #include <linux/in6.h>
  34 #include <linux/netdevice.h>
  35 #include <linux/if_arp.h>
  36 #include <linux/icmpv6.h>
  37 #include <linux/init.h>
  38 #include <linux/route.h>
  39 #include <linux/rtnetlink.h>
  40 #include <linux/netfilter_ipv6.h>
  41 #include <linux/slab.h>
  42 #include <linux/hash.h>
  43 #include <linux/etherdevice.h>
  44
  45 #include <asm/uaccess.h>
  46 #include <linux/atomic.h>
  47
  48 #include <net/icmp.h>
  49 #include <net/ip.h>
  50 #include <net/ip_tunnels.h>
  51 #include <net/ipv6.h>
  52 #include <net/ip6_route.h>
  53 #include <net/addrconf.h>
  54 #include <net/ip6_tunnel.h>
  55 #include <net/xfrm.h>
  56 #include <net/dsfield.h>
  57 #include <net/inet_ecn.h>
  58 #include <net/net_namespace.h>
  59 #include <net/netns/generic.h>
  60
  61 MODULE_AUTHOR("Ville Nuorvala");
  62 MODULE_DESCRIPTION("IPv6 tunneling device");
  63 MODULE_LICENSE("GPL");
  64 MODULE_ALIAS_RTNL_LINK("ip6tnl");
  65 MODULE_ALIAS_NETDEV("ip6tnl0");
  66
  67 #define HASH_SIZE_SHIFT  5
  68 #define HASH_SIZE (1 << HASH_SIZE_SHIFT)
  69
  70 static bool log_ecn_error = true;
  71 module_param(log_ecn_error, bool, 0644);
  72 MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");
  73
  74 static u32 HASH(const struct in6_addr *addr1, const struct in6_addr *addr2)
  75 {
  76         u32 hash = ipv6_addr_hash(addr1) ^ ipv6_addr_hash(addr2);
  77
  78         return hash_32(hash, HASH_SIZE_SHIFT);
  79 }
  80
  81 static int ip6_tnl_dev_init(struct net_device *dev);
  82 static void ip6_tnl_dev_setup(struct net_device *dev);
  83 static struct rtnl_link_ops ip6_link_ops __read_mostly;
  84
  85 static int ip6_tnl_net_id __read_mostly;
  86 struct ip6_tnl_net {
  87         /* the IPv6 tunnel fallback device */
  88         struct net_device *fb_tnl_dev;
  89         /* lists for storing tunnels in use */
  90         struct ip6_tnl __rcu *tnls_r_l[HASH_SIZE];
  91         struct ip6_tnl __rcu *tnls_wc[1];
  92         struct ip6_tnl __rcu **tnls[2];
  93 };
  94
  95 static struct net_device_stats *ip6_get_stats(struct net_device *dev)
  96 {
  97         struct pcpu_sw_netstats tmp, sum = { 0 };
  98         int i;
  99
 100         for_each_possible_cpu(i) {
 101                 unsigned int start;
 102                 const struct pcpu_sw_netstats *tstats =
 103                                                    per_cpu_ptr(dev->tstats, i);
 104
 105                 do {
 106                         start = u64_stats_fetch_begin_irq(&tstats->syncp);
 107                         tmp.rx_packets = tstats->rx_packets;
 108                         tmp.rx_bytes = tstats->rx_bytes;
 109                         tmp.tx_packets = tstats->tx_packets;
 110                         tmp.tx_bytes =  tstats->tx_bytes;
 111                 } while (u64_stats_fetch_retry_irq(&tstats->syncp, start));
 112
 113                 sum.rx_packets += tmp.rx_packets;
 114                 sum.rx_bytes   += tmp.rx_bytes;
 115                 sum.tx_packets += tmp.tx_packets;
 116                 sum.tx_bytes   += tmp.tx_bytes;
 117         }
 118         dev->stats.rx_packets = sum.rx_packets;
 119         dev->stats.rx_bytes   = sum.rx_bytes;
 120         dev->stats.tx_packets = sum.tx_packets;
 121         dev->stats.tx_bytes   = sum.tx_bytes;
 122         return &dev->stats;
 123 }
 124
 125 /**
 126  * ip6_tnl_lookup - fetch tunnel matching the end-point addresses
 127  *   @remote: the address of the tunnel exit-point
 128  *   @local: the address of the tunnel entry-point
 129  *
 130  * Return:
 131  *   tunnel matching given end-points if found,
 132  *   else fallback tunnel if its device is up,
 133  *   else %NULL
 134  **/
 135
 136 #define for_each_ip6_tunnel_rcu(start) \
 137         for (t = rcu_dereference(start); t; t = rcu_dereference(t->next))
 138
 139 static struct ip6_tnl *
 140 ip6_tnl_lookup(struct net *net, const struct in6_addr *remote, const struct in6_addr *local)
 141 {
 142         unsigned int hash = HASH(remote, local);
 143         struct ip6_tnl *t;
 144         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
 145         struct in6_addr any;
 146
 147         for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
 148                 if (ipv6_addr_equal(local, &t->parms.laddr) &&
 149                     ipv6_addr_equal(remote, &t->parms.raddr) &&
 150                     (t->dev->flags & IFF_UP))
 151                         return t;
 152         }
 153
 154         memset(&any, 0, sizeof(any));
 155         hash = HASH(&any, local);
 156         for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
 157                 if (ipv6_addr_equal(local, &t->parms.laddr) &&
 158                     (t->dev->flags & IFF_UP))
 159                         return t;
 160         }
 161
 162         hash = HASH(remote, &any);
 163         for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
 164                 if (ipv6_addr_equal(remote, &t->parms.raddr) &&
 165                     (t->dev->flags & IFF_UP))
 166                         return t;
 167         }
 168
 169         t = rcu_dereference(ip6n->tnls_wc[0]);
 170         if (t && (t->dev->flags & IFF_UP))
 171                 return t;
 172
 173         return NULL;
 174 }
 175
 176 /**
 177  * ip6_tnl_bucket - get head of list matching given tunnel parameters
 178  *   @p: parameters containing tunnel end-points
 179  *
 180  * Description:
 181  *   ip6_tnl_bucket() returns the head of the list matching the
 182  *   &struct in6_addr entries laddr and raddr in @p.
 183  *
 184  * Return: head of IPv6 tunnel list
 185  **/
 186
 187 static struct ip6_tnl __rcu **
 188 ip6_tnl_bucket(struct ip6_tnl_net *ip6n, const struct __ip6_tnl_parm *p)
 189 {
 190         const struct in6_addr *remote = &p->raddr;
 191         const struct in6_addr *local = &p->laddr;
 192         unsigned int h = 0;
 193         int prio = 0;
 194
 195         if (!ipv6_addr_any(remote) || !ipv6_addr_any(local)) {
 196                 prio = 1;
 197                 h = HASH(remote, local);
 198         }
 199         return &ip6n->tnls[prio][h];
 200 }
 201
 202 /**
 203  * ip6_tnl_link - add tunnel to hash table
 204  *   @t: tunnel to be added
 205  **/
 206
 207 static void
 208 ip6_tnl_link(struct ip6_tnl_net *ip6n, struct ip6_tnl *t)
 209 {
 210         struct ip6_tnl __rcu **tp = ip6_tnl_bucket(ip6n, &t->parms);
 211
 212         rcu_assign_pointer(t->next , rtnl_dereference(*tp));
 213         rcu_assign_pointer(*tp, t);
 214 }
 215
 216 /**
 217  * ip6_tnl_unlink - remove tunnel from hash table
 218  *   @t: tunnel to be removed
 219  **/
 220
 221 static void
 222 ip6_tnl_unlink(struct ip6_tnl_net *ip6n, struct ip6_tnl *t)
 223 {
 224         struct ip6_tnl __rcu **tp;
 225         struct ip6_tnl *iter;
 226
 227         for (tp = ip6_tnl_bucket(ip6n, &t->parms);
 228              (iter = rtnl_dereference(*tp)) != NULL;
 229              tp = &iter->next) {
 230                 if (t == iter) {
 231                         rcu_assign_pointer(*tp, t->next);
 232                         break;
 233                 }
 234         }
 235 }
 236
 237 static void ip6_dev_free(struct net_device *dev)
 238 {
 239         struct ip6_tnl *t = netdev_priv(dev);
 240
 241         gro_cells_destroy(&t->gro_cells);
 242         dst_cache_destroy(&t->dst_cache);
 243         free_percpu(dev->tstats);
 244         free_netdev(dev);
 245 }
 246
 247 static int ip6_tnl_create2(struct net_device *dev)
 248 {
 249         struct ip6_tnl *t = netdev_priv(dev);
 250         struct net *net = dev_net(dev);
 251         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
 252         int err;
 253
 254         t = netdev_priv(dev);
 255
 256         dev->rtnl_link_ops = &ip6_link_ops;
 257         err = register_netdevice(dev);
 258         if (err < 0)
 259                 goto out;
 260
 261         strcpy(t->parms.name, dev->name);
 262
 263         dev_hold(dev);
 264         ip6_tnl_link(ip6n, t);
 265         return 0;
 266
 267 out:
 268         return err;
 269 }
 270
 271 /**
 272  * ip6_tnl_create - create a new tunnel
 273  *   @p: tunnel parameters
 274  *   @pt: pointer to new tunnel
 275  *
 276  * Description:
 277  *   Create tunnel matching given parameters.
 278  *
 279  * Return:
 280  *   created tunnel or error pointer
 281  **/
 282
 283 static struct ip6_tnl *ip6_tnl_create(struct net *net, struct __ip6_tnl_parm *p)
 284 {
 285         struct net_device *dev;
 286         struct ip6_tnl *t;
 287         char name[IFNAMSIZ];
 288         int err = -ENOMEM;
 289
 290         if (p->name[0])
 291                 strlcpy(name, p->name, IFNAMSIZ);
 292         else
 293                 sprintf(name, "ip6tnl%%d");
 294
 295         dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN,
 296                            ip6_tnl_dev_setup);
 297         if (!dev)
 298                 goto failed;
 299
 300         dev_net_set(dev, net);
 301
 302         t = netdev_priv(dev);
 303         t->parms = *p;
 304         t->net = dev_net(dev);
 305         err = ip6_tnl_create2(dev);
 306         if (err < 0)
 307                 goto failed_free;
 308
 309         return t;
 310
 311 failed_free:
 312         ip6_dev_free(dev);
 313 failed:
 314         return ERR_PTR(err);
 315 }
 316
 317 /**
 318  * ip6_tnl_locate - find or create tunnel matching given parameters
 319  *   @p: tunnel parameters
 320  *   @create: != 0 if allowed to create new tunnel if no match found
 321  *
 322  * Description:
 323  *   ip6_tnl_locate() first tries to locate an existing tunnel
 324  *   based on @parms. If this is unsuccessful, but @create is set a new
 325  *   tunnel device is created and registered for use.
 326  *
 327  * Return:
 328  *   matching tunnel or error pointer
 329  **/
 330
 331 static struct ip6_tnl *ip6_tnl_locate(struct net *net,
 332                 struct __ip6_tnl_parm *p, int create)
 333 {
 334         const struct in6_addr *remote = &p->raddr;
 335         const struct in6_addr *local = &p->laddr;
 336         struct ip6_tnl __rcu **tp;
 337         struct ip6_tnl *t;
 338         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
 339
 340         for (tp = ip6_tnl_bucket(ip6n, p);
 341              (t = rtnl_dereference(*tp)) != NULL;
 342              tp = &t->next) {
 343                 if (ipv6_addr_equal(local, &t->parms.laddr) &&
 344                     ipv6_addr_equal(remote, &t->parms.raddr)) {
 345                         if (create)
 346                                 return ERR_PTR(-EEXIST);
 347
 348                         return t;
 349                 }
 350         }
 351         if (!create)
 352                 return ERR_PTR(-ENODEV);
 353         return ip6_tnl_create(net, p);
 354 }
 355
 356 /**
 357  * ip6_tnl_dev_uninit - tunnel device uninitializer
 358  *   @dev: the device to be destroyed
 359  *
 360  * Description:
 361  *   ip6_tnl_dev_uninit() removes tunnel from its list
 362  **/
 363
 364 static void
 365 ip6_tnl_dev_uninit(struct net_device *dev)
 366 {
 367         struct ip6_tnl *t = netdev_priv(dev);
 368         struct net *net = t->net;
 369         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
 370
 371         if (dev == ip6n->fb_tnl_dev)
 372                 RCU_INIT_POINTER(ip6n->tnls_wc[0], NULL);
 373         else
 374                 ip6_tnl_unlink(ip6n, t);
 375         dst_cache_reset(&t->dst_cache);
 376         dev_put(dev);
 377 }
 378
 379 /**
 380  * parse_tvl_tnl_enc_lim - handle encapsulation limit option
 381  *   @skb: received socket buffer
 382  *
 383  * Return:
 384  *   0 if none was found,
 385  *   else index to encapsulation limit
 386  **/
 387
 388 __u16 ip6_tnl_parse_tlv_enc_lim(struct sk_buff *skb, __u8 *raw)
 389 {
 390         const struct ipv6hdr *ipv6h = (const struct ipv6hdr *) raw;
 391         __u8 nexthdr = ipv6h->nexthdr;
 392         __u16 off = sizeof(*ipv6h);
 393
 394         while (ipv6_ext_hdr(nexthdr) && nexthdr != NEXTHDR_NONE) {
 395                 __u16 optlen = 0;
 396                 struct ipv6_opt_hdr *hdr;
 397                 if (raw + off + sizeof(*hdr) > skb->data &&
 398                     !pskb_may_pull(skb, raw - skb->data + off + sizeof (*hdr)))
 399                         break;
 400
 401                 hdr = (struct ipv6_opt_hdr *) (raw + off);
 402                 if (nexthdr == NEXTHDR_FRAGMENT) {
 403                         struct frag_hdr *frag_hdr = (struct frag_hdr *) hdr;
 404                         if (frag_hdr->frag_off)
 405                                 break;
 406                         optlen = 8;
 407                 } else if (nexthdr == NEXTHDR_AUTH) {
 408                         optlen = (hdr->hdrlen + 2) << 2;
 409                 } else {
 410                         optlen = ipv6_optlen(hdr);
 411                 }
 412                 if (nexthdr == NEXTHDR_DEST) {
 413                         __u16 i = off + 2;
 414                         while (1) {
 415                                 struct ipv6_tlv_tnl_enc_lim *tel;
 416
 417                                 /* No more room for encapsulation limit */
 418                                 if (i + sizeof (*tel) > off + optlen)
 419                                         break;
 420
 421                                 tel = (struct ipv6_tlv_tnl_enc_lim *) &raw[i];
 422                                 /* return index of option if found and valid */
 423                                 if (tel->type == IPV6_TLV_TNL_ENCAP_LIMIT &&
 424                                     tel->length == 1)
 425                                         return i;
 426                                 /* else jump to next option */
 427                                 if (tel->type)
 428                                         i += tel->length + 2;
 429                                 else
 430                                         i++;
 431                         }
 432                 }
 433                 nexthdr = hdr->nexthdr;
 434                 off += optlen;
 435         }
 436         return 0;
 437 }
 438 EXPORT_SYMBOL(ip6_tnl_parse_tlv_enc_lim);
 439
 440 /**
 441  * ip6_tnl_err - tunnel error handler
 442  *
 443  * Description:
 444  *   ip6_tnl_err() should handle errors in the tunnel according
 445  *   to the specifications in RFC 2473.
 446  **/
 447
 448 static int
 449 ip6_tnl_err(struct sk_buff *skb, __u8 ipproto, struct inet6_skb_parm *opt,
 450             u8 *type, u8 *code, int *msg, __u32 *info, int offset)
 451 {
 452         const struct ipv6hdr *ipv6h = (const struct ipv6hdr *) skb->data;
 453         struct ip6_tnl *t;
 454         int rel_msg = 0;
 455         u8 rel_type = ICMPV6_DEST_UNREACH;
 456         u8 rel_code = ICMPV6_ADDR_UNREACH;
 457         u8 tproto;
 458         __u32 rel_info = 0;
 459         __u16 len;
 460         int err = -ENOENT;
 461
 462         /* If the packet doesn't contain the original IPv6 header we are
 463            in trouble since we might need the source address for further
 464            processing of the error. */
 465
 466         rcu_read_lock();
 467         t = ip6_tnl_lookup(dev_net(skb->dev), &ipv6h->daddr, &ipv6h->saddr);
 468         if (!t)
 469                 goto out;
 470
 471         tproto = ACCESS_ONCE(t->parms.proto);
 472         if (tproto != ipproto && tproto != 0)
 473                 goto out;
 474
 475         err = 0;
 476
 477         switch (*type) {
 478                 __u32 teli;
 479                 struct ipv6_tlv_tnl_enc_lim *tel;
 480                 __u32 mtu;
 481         case ICMPV6_DEST_UNREACH:
 482                 net_dbg_ratelimited("%s: Path to destination invalid or inactive!\n",
 483                                     t->parms.name);
 484                 rel_msg = 1;
 485                 break;
 486         case ICMPV6_TIME_EXCEED:
 487                 if ((*code) == ICMPV6_EXC_HOPLIMIT) {
 488                         net_dbg_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n",
 489                                             t->parms.name);
 490                         rel_msg = 1;
 491                 }
 492                 break;
 493         case ICMPV6_PARAMPROB:
 494                 teli = 0;
 495                 if ((*code) == ICMPV6_HDR_FIELD)
 496                         teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data);
 497
 498                 if (teli && teli == *info - 2) {
 499                         tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli];
 500                         if (tel->encap_limit == 0) {
 501                                 net_dbg_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n",
 502                                                     t->parms.name);
 503                                 rel_msg = 1;
 504                         }
 505                 } else {
 506                         net_dbg_ratelimited("%s: Recipient unable to parse tunneled packet!\n",
 507                                             t->parms.name);
 508                 }
 509                 break;
 510         case ICMPV6_PKT_TOOBIG:
 511                 mtu = *info - offset;
 512                 if (mtu < IPV6_MIN_MTU)
 513                         mtu = IPV6_MIN_MTU;
 514                 t->dev->mtu = mtu;
 515
 516                 len = sizeof(*ipv6h) + ntohs(ipv6h->payload_len);
 517                 if (len > mtu) {
 518                         rel_type = ICMPV6_PKT_TOOBIG;
 519                         rel_code = 0;
 520                         rel_info = mtu;
 521                         rel_msg = 1;
 522                 }
 523                 break;
 524         }
 525
 526         *type = rel_type;
 527         *code = rel_code;
 528         *info = rel_info;
 529         *msg = rel_msg;
 530
 531 out:
 532         rcu_read_unlock();
 533         return err;
 534 }
 535
 536 static int
 537 ip4ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 538            u8 type, u8 code, int offset, __be32 info)
 539 {
 540         int rel_msg = 0;
 541         u8 rel_type = type;
 542         u8 rel_code = code;
 543         __u32 rel_info = ntohl(info);
 544         int err;
 545         struct sk_buff *skb2;
 546         const struct iphdr *eiph;
 547         struct rtable *rt;
 548         struct flowi4 fl4;
 549
 550         err = ip6_tnl_err(skb, IPPROTO_IPIP, opt, &rel_type, &rel_code,
 551                           &rel_msg, &rel_info, offset);
 552         if (err < 0)
 553                 return err;
 554
 555         if (rel_msg == 0)
 556                 return 0;
 557
 558         switch (rel_type) {
 559         case ICMPV6_DEST_UNREACH:
 560                 if (rel_code != ICMPV6_ADDR_UNREACH)
 561                         return 0;
 562                 rel_type = ICMP_DEST_UNREACH;
 563                 rel_code = ICMP_HOST_UNREACH;
 564                 break;
 565         case ICMPV6_PKT_TOOBIG:
 566                 if (rel_code != 0)
 567                         return 0;
 568                 rel_type = ICMP_DEST_UNREACH;
 569                 rel_code = ICMP_FRAG_NEEDED;
 570                 break;
 571         case NDISC_REDIRECT:
 572                 rel_type = ICMP_REDIRECT;
 573                 rel_code = ICMP_REDIR_HOST;
 574         default:
 575                 return 0;
 576         }
 577
 578         if (!pskb_may_pull(skb, offset + sizeof(struct iphdr)))
 579                 return 0;
 580
 581         skb2 = skb_clone(skb, GFP_ATOMIC);
 582         if (!skb2)
 583                 return 0;
 584
 585         skb_dst_drop(skb2);
 586
 587         skb_pull(skb2, offset);
 588         skb_reset_network_header(skb2);
 589         eiph = ip_hdr(skb2);
 590
 591         /* Try to guess incoming interface */
 592         rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL,
 593                                    eiph->saddr, 0,
 594                                    0, 0,
 595                                    IPPROTO_IPIP, RT_TOS(eiph->tos), 0);
 596         if (IS_ERR(rt))
 597                 goto out;
 598
 599         skb2->dev = rt->dst.dev;
 600
 601         /* route "incoming" packet */
 602         if (rt->rt_flags & RTCF_LOCAL) {
 603                 ip_rt_put(rt);
 604                 rt = NULL;
 605                 rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL,
 606                                            eiph->daddr, eiph->saddr,
 607                                            0, 0,
 608                                            IPPROTO_IPIP,
 609                                            RT_TOS(eiph->tos), 0);
 610                 if (IS_ERR(rt) ||
 611                     rt->dst.dev->type != ARPHRD_TUNNEL) {
 612                         if (!IS_ERR(rt))
 613                                 ip_rt_put(rt);
 614                         goto out;
 615                 }
 616                 skb_dst_set(skb2, &rt->dst);
 617         } else {
 618                 ip_rt_put(rt);
 619                 if (ip_route_input(skb2, eiph->daddr, eiph->saddr, eiph->tos,
 620                                    skb2->dev) ||
 621                     skb_dst(skb2)->dev->type != ARPHRD_TUNNEL)
 622                         goto out;
 623         }
 624
 625         /* change mtu on this route */
 626         if (rel_type == ICMP_DEST_UNREACH && rel_code == ICMP_FRAG_NEEDED) {
 627                 if (rel_info > dst_mtu(skb_dst(skb2)))
 628                         goto out;
 629
 630                 skb_dst(skb2)->ops->update_pmtu(skb_dst(skb2), NULL, skb2, rel_info);
 631         }
 632         if (rel_type == ICMP_REDIRECT)
 633                 skb_dst(skb2)->ops->redirect(skb_dst(skb2), NULL, skb2);
 634
 635         icmp_send(skb2, rel_type, rel_code, htonl(rel_info));
 636
 637 out:
 638         kfree_skb(skb2);
 639         return 0;
 640 }
 641
 642 static int
 643 ip6ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 644            u8 type, u8 code, int offset, __be32 info)
 645 {
 646         int rel_msg = 0;
 647         u8 rel_type = type;
 648         u8 rel_code = code;
 649         __u32 rel_info = ntohl(info);
 650         int err;
 651
 652         err = ip6_tnl_err(skb, IPPROTO_IPV6, opt, &rel_type, &rel_code,
 653                           &rel_msg, &rel_info, offset);
 654         if (err < 0)
 655                 return err;
 656
 657         if (rel_msg && pskb_may_pull(skb, offset + sizeof(struct ipv6hdr))) {
 658                 struct rt6_info *rt;
 659                 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
 660
 661                 if (!skb2)
 662                         return 0;
 663
 664                 skb_dst_drop(skb2);
 665                 skb_pull(skb2, offset);
 666                 skb_reset_network_header(skb2);
 667
 668                 /* Try to guess incoming interface */
 669                 rt = rt6_lookup(dev_net(skb->dev), &ipv6_hdr(skb2)->saddr,
 670                                 NULL, 0, 0);
 671
 672                 if (rt && rt->dst.dev)
 673                         skb2->dev = rt->dst.dev;
 674
 675                 icmpv6_send(skb2, rel_type, rel_code, rel_info);
 676
 677                 ip6_rt_put(rt);
 678
 679                 kfree_skb(skb2);
 680         }
 681
 682         return 0;
 683 }
 684
 685 static int ip4ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t,
 686                                        const struct ipv6hdr *ipv6h,
 687                                        struct sk_buff *skb)
 688 {
 689         __u8 dsfield = ipv6_get_dsfield(ipv6h) & ~INET_ECN_MASK;
 690
 691         if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY)
 692                 ipv4_change_dsfield(ip_hdr(skb), INET_ECN_MASK, dsfield);
 693
 694         return IP6_ECN_decapsulate(ipv6h, skb);
 695 }
 696
 697 static int ip6ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t,
 698                                        const struct ipv6hdr *ipv6h,
 699                                        struct sk_buff *skb)
 700 {
 701         if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY)
 702                 ipv6_copy_dscp(ipv6_get_dsfield(ipv6h), ipv6_hdr(skb));
 703
 704         return IP6_ECN_decapsulate(ipv6h, skb);
 705 }
 706
 707 __u32 ip6_tnl_get_cap(struct ip6_tnl *t,
 708                              const struct in6_addr *laddr,
 709                              const struct in6_addr *raddr)
 710 {
 711         struct __ip6_tnl_parm *p = &t->parms;
 712         int ltype = ipv6_addr_type(laddr);
 713         int rtype = ipv6_addr_type(raddr);
 714         __u32 flags = 0;
 715
 716         if (ltype == IPV6_ADDR_ANY || rtype == IPV6_ADDR_ANY) {
 717                 flags = IP6_TNL_F_CAP_PER_PACKET;
 718         } else if (ltype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) &&
 719                    rtype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) &&
 720                    !((ltype|rtype) & IPV6_ADDR_LOOPBACK) &&
 721                    (!((ltype|rtype) & IPV6_ADDR_LINKLOCAL) || p->link)) {
 722                 if (ltype&IPV6_ADDR_UNICAST)
 723                         flags |= IP6_TNL_F_CAP_XMIT;
 724                 if (rtype&IPV6_ADDR_UNICAST)
 725                         flags |= IP6_TNL_F_CAP_RCV;
 726         }
 727         return flags;
 728 }
 729 EXPORT_SYMBOL(ip6_tnl_get_cap);
 730
 731 /* called with rcu_read_lock() */
 732 int ip6_tnl_rcv_ctl(struct ip6_tnl *t,
 733                                   const struct in6_addr *laddr,
 734                                   const struct in6_addr *raddr)
 735 {
 736         struct __ip6_tnl_parm *p = &t->parms;
 737         int ret = 0;
 738         struct net *net = t->net;
 739
 740         if ((p->flags & IP6_TNL_F_CAP_RCV) ||
 741             ((p->flags & IP6_TNL_F_CAP_PER_PACKET) &&
 742              (ip6_tnl_get_cap(t, laddr, raddr) & IP6_TNL_F_CAP_RCV))) {
 743                 struct net_device *ldev = NULL;
 744
 745                 if (p->link)
 746                         ldev = dev_get_by_index_rcu(net, p->link);
 747
 748                 if ((ipv6_addr_is_multicast(laddr) ||
 749                      likely(ipv6_chk_addr(net, laddr, ldev, 0))) &&
 750                     likely(!ipv6_chk_addr(net, raddr, NULL, 0)))
 751                         ret = 1;
 752         }
 753         return ret;
 754 }
 755 EXPORT_SYMBOL_GPL(ip6_tnl_rcv_ctl);
 756
 757 static int __ip6_tnl_rcv(struct ip6_tnl *tunnel, struct sk_buff *skb,
 758                          const struct tnl_ptk_info *tpi,
 759                          struct metadata_dst *tun_dst,
 760                          int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t,
 761                                                 const struct ipv6hdr *ipv6h,
 762                                                 struct sk_buff *skb),
 763                          bool log_ecn_err)
 764 {
 765         struct pcpu_sw_netstats *tstats;
 766         const struct ipv6hdr *ipv6h = ipv6_hdr(skb);
 767         int err;
 768
 769         if ((!(tpi->flags & TUNNEL_CSUM) &&
 770              (tunnel->parms.i_flags & TUNNEL_CSUM)) ||
 771             ((tpi->flags & TUNNEL_CSUM) &&
 772              !(tunnel->parms.i_flags & TUNNEL_CSUM))) {
 773                 tunnel->dev->stats.rx_crc_errors++;
 774                 tunnel->dev->stats.rx_errors++;
 775                 goto drop;
 776         }
 777
 778         if (tunnel->parms.i_flags & TUNNEL_SEQ) {
 779                 if (!(tpi->flags & TUNNEL_SEQ) ||
 780                     (tunnel->i_seqno &&
 781                      (s32)(ntohl(tpi->seq) - tunnel->i_seqno) < 0)) {
 782                         tunnel->dev->stats.rx_fifo_errors++;
 783                         tunnel->dev->stats.rx_errors++;
 784                         goto drop;
 785                 }
 786                 tunnel->i_seqno = ntohl(tpi->seq) + 1;
 787         }
 788
 789         skb->protocol = tpi->proto;
 790
 791         /* Warning: All skb pointers will be invalidated! */
 792         if (tunnel->dev->type == ARPHRD_ETHER) {
 793                 if (!pskb_may_pull(skb, ETH_HLEN)) {
 794                         tunnel->dev->stats.rx_length_errors++;
 795                         tunnel->dev->stats.rx_errors++;
 796                         goto drop;
 797                 }
 798
 799                 ipv6h = ipv6_hdr(skb);
 800                 skb->protocol = eth_type_trans(skb, tunnel->dev);
 801                 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);
 802         } else {
 803                 skb->dev = tunnel->dev;
 804         }
 805
 806         skb_reset_network_header(skb);
 807         memset(skb->cb, 0, sizeof(struct inet6_skb_parm));
 808
 809         __skb_tunnel_rx(skb, tunnel->dev, tunnel->net);
 810
 811         err = dscp_ecn_decapsulate(tunnel, ipv6h, skb);
 812         if (unlikely(err)) {
 813                 if (log_ecn_err)
 814                         net_info_ratelimited("non-ECT from %pI6 with DS=%#x\n",
 815                                              &ipv6h->saddr,
 816                                              ipv6_get_dsfield(ipv6h));
 817                 if (err > 1) {
 818                         ++tunnel->dev->stats.rx_frame_errors;
 819                         ++tunnel->dev->stats.rx_errors;
 820                         goto drop;
 821                 }
 822         }
 823
 824         tstats = this_cpu_ptr(tunnel->dev->tstats);
 825         u64_stats_update_begin(&tstats->syncp);
 826         tstats->rx_packets++;
 827         tstats->rx_bytes += skb->len;
 828         u64_stats_update_end(&tstats->syncp);
 829
 830         skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(tunnel->dev)));
 831
 832         gro_cells_receive(&tunnel->gro_cells, skb);
 833         return 0;
 834
 835 drop:
 836         kfree_skb(skb);
 837         return 0;
 838 }
 839
 840 int ip6_tnl_rcv(struct ip6_tnl *t, struct sk_buff *skb,
 841                 const struct tnl_ptk_info *tpi,
 842                 struct metadata_dst *tun_dst,
 843                 bool log_ecn_err)
 844 {
 845         return __ip6_tnl_rcv(t, skb, tpi, NULL, ip6ip6_dscp_ecn_decapsulate,
 846                              log_ecn_err);
 847 }
 848 EXPORT_SYMBOL(ip6_tnl_rcv);
 849
 850 static const struct tnl_ptk_info tpi_v6 = {
 851         /* no tunnel info required for ipxip6. */
 852         .proto = htons(ETH_P_IPV6),
 853 };
 854
 855 static const struct tnl_ptk_info tpi_v4 = {
 856         /* no tunnel info required for ipxip6. */
 857         .proto = htons(ETH_P_IP),
 858 };
 859
 860 static int ipxip6_rcv(struct sk_buff *skb, u8 ipproto,
 861                       const struct tnl_ptk_info *tpi,
 862                       int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t,
 863                                                   const struct ipv6hdr *ipv6h,
 864                                                   struct sk_buff *skb))
 865 {
 866         struct ip6_tnl *t;
 867         const struct ipv6hdr *ipv6h = ipv6_hdr(skb);
 868         int ret = -1;
 869
 870         rcu_read_lock();
 871         t = ip6_tnl_lookup(dev_net(skb->dev), &ipv6h->saddr, &ipv6h->daddr);
 872
 873         if (t) {
 874                 u8 tproto = ACCESS_ONCE(t->parms.proto);
 875
 876                 if (tproto != ipproto && tproto != 0)
 877                         goto drop;
 878                 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
 879                         goto drop;
 880                 if (!ip6_tnl_rcv_ctl(t, &ipv6h->daddr, &ipv6h->saddr))
 881                         goto drop;
 882                 if (iptunnel_pull_header(skb, 0, tpi->proto, false))
 883                         goto drop;
 884                 ret = __ip6_tnl_rcv(t, skb, tpi, NULL, dscp_ecn_decapsulate,
 885                                     log_ecn_error);
 886         }
 887
 888         rcu_read_unlock();
 889
 890         return ret;
 891
 892 drop:
 893         rcu_read_unlock();
 894         kfree_skb(skb);
 895         return 0;
 896 }
 897
 898 static int ip4ip6_rcv(struct sk_buff *skb)
 899 {
 900         return ipxip6_rcv(skb, IPPROTO_IPIP, &tpi_v4,
 901                           ip4ip6_dscp_ecn_decapsulate);
 902 }
 903
 904 static int ip6ip6_rcv(struct sk_buff *skb)
 905 {
 906         return ipxip6_rcv(skb, IPPROTO_IPV6, &tpi_v6,
 907                           ip6ip6_dscp_ecn_decapsulate);
 908 }
 909
 910 struct ipv6_tel_txoption {
 911         struct ipv6_txoptions ops;
 912         __u8 dst_opt[8];
 913 };
 914
 915 static void init_tel_txopt(struct ipv6_tel_txoption *opt, __u8 encap_limit)
 916 {
 917         memset(opt, 0, sizeof(struct ipv6_tel_txoption));
 918
 919         opt->dst_opt[2] = IPV6_TLV_TNL_ENCAP_LIMIT;
 920         opt->dst_opt[3] = 1;
 921         opt->dst_opt[4] = encap_limit;
 922         opt->dst_opt[5] = IPV6_TLV_PADN;
 923         opt->dst_opt[6] = 1;
 924
 925         opt->ops.dst0opt = (struct ipv6_opt_hdr *) opt->dst_opt;
 926         opt->ops.opt_nflen = 8;
 927 }
 928
 929 /**
 930  * ip6_tnl_addr_conflict - compare packet addresses to tunnel's own
 931  *   @t: the outgoing tunnel device
 932  *   @hdr: IPv6 header from the incoming packet
 933  *
 934  * Description:
 935  *   Avoid trivial tunneling loop by checking that tunnel exit-point
 936  *   doesn't match source of incoming packet.
 937  *
 938  * Return:
 939  *   1 if conflict,
 940  *   0 else
 941  **/
 942
 943 static inline bool
 944 ip6_tnl_addr_conflict(const struct ip6_tnl *t, const struct ipv6hdr *hdr)
 945 {
 946         return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr);
 947 }
 948
 949 int ip6_tnl_xmit_ctl(struct ip6_tnl *t,
 950                      const struct in6_addr *laddr,
 951                      const struct in6_addr *raddr)
 952 {
 953         struct __ip6_tnl_parm *p = &t->parms;
 954         int ret = 0;
 955         struct net *net = t->net;
 956
 957         if ((p->flags & IP6_TNL_F_CAP_XMIT) ||
 958             ((p->flags & IP6_TNL_F_CAP_PER_PACKET) &&
 959              (ip6_tnl_get_cap(t, laddr, raddr) & IP6_TNL_F_CAP_XMIT))) {
 960                 struct net_device *ldev = NULL;
 961
 962                 rcu_read_lock();
 963                 if (p->link)
 964                         ldev = dev_get_by_index_rcu(net, p->link);
 965
 966                 if (unlikely(!ipv6_chk_addr(net, laddr, ldev, 0)))
 967                         pr_warn("%s xmit: Local address not yet configured!\n",
 968                                 p->name);
 969                 else if (!ipv6_addr_is_multicast(raddr) &&
 970                          unlikely(ipv6_chk_addr(net, raddr, NULL, 0)))
 971                         pr_warn("%s xmit: Routing loop! Remote address found on this node!\n",
 972                                 p->name);
 973                 else
 974                         ret = 1;
 975                 rcu_read_unlock();
 976         }
 977         return ret;
 978 }
 979 EXPORT_SYMBOL_GPL(ip6_tnl_xmit_ctl);
 980
 981 /**
 982  * ip6_tnl_xmit - encapsulate packet and send
 983  *   @skb: the outgoing socket buffer
 984  *   @dev: the outgoing tunnel device
 985  *   @dsfield: dscp code for outer header
 986  *   @fl6: flow of tunneled packet
 987  *   @encap_limit: encapsulation limit
 988  *   @pmtu: Path MTU is stored if packet is too big
 989  *   @proto: next header value
 990  *
 991  * Description:
 992  *   Build new header and do some sanity checks on the packet before sending
 993  *   it.
 994  *
 995  * Return:
 996  *   0 on success
 997  *   -1 fail
 998  *   %-EMSGSIZE message too big. return mtu in this case.
 999  **/
1000
1001 int ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev, __u8 dsfield,
1002                  struct flowi6 *fl6, int encap_limit, __u32 *pmtu,
1003                  __u8 proto)
1004 {
1005         struct ip6_tnl *t = netdev_priv(dev);
1006         struct net *net = t->net;
1007         struct net_device_stats *stats = &t->dev->stats;
1008         struct ipv6hdr *ipv6h = ipv6_hdr(skb);
1009         struct ipv6_tel_txoption opt;
1010         struct dst_entry *dst = NULL, *ndst = NULL;
1011         struct net_device *tdev;
1012         int mtu;
1013         unsigned int max_headroom = sizeof(struct ipv6hdr);
1014         int err = -1;
1015
1016         /* NBMA tunnel */
1017         if (ipv6_addr_any(&t->parms.raddr)) {
1018                 struct in6_addr *addr6;
1019                 struct neighbour *neigh;
1020                 int addr_type;
1021
1022                 if (!skb_dst(skb))
1023                         goto tx_err_link_failure;
1024
1025                 neigh = dst_neigh_lookup(skb_dst(skb),
1026                                          &ipv6_hdr(skb)->daddr);
1027                 if (!neigh)
1028                         goto tx_err_link_failure;
1029
1030                 addr6 = (struct in6_addr *)&neigh->primary_key;
1031                 addr_type = ipv6_addr_type(addr6);
1032
1033                 if (addr_type == IPV6_ADDR_ANY)
1034                         addr6 = &ipv6_hdr(skb)->daddr;
1035
1036                 memcpy(&fl6->daddr, addr6, sizeof(fl6->daddr));
1037                 neigh_release(neigh);
1038         } else if (!fl6->flowi6_mark)
1039                 dst = dst_cache_get(&t->dst_cache);
1040
1041         if (!ip6_tnl_xmit_ctl(t, &fl6->saddr, &fl6->daddr))
1042                 goto tx_err_link_failure;
1043
1044         if (!dst) {
1045                 dst = ip6_route_output(net, NULL, fl6);
1046
1047                 if (dst->error)
1048                         goto tx_err_link_failure;
1049                 dst = xfrm_lookup(net, dst, flowi6_to_flowi(fl6), NULL, 0);
1050                 if (IS_ERR(dst)) {
1051                         err = PTR_ERR(dst);
1052                         dst = NULL;
1053                         goto tx_err_link_failure;
1054                 }
1055                 ndst = dst;
1056         }
1057
1058         tdev = dst->dev;
1059
1060         if (tdev == dev) {
1061                 stats->collisions++;
1062                 net_warn_ratelimited("%s: Local routing loop detected!\n",
1063                                      t->parms.name);
1064                 goto tx_err_dst_release;
1065         }
1066         mtu = dst_mtu(dst) - sizeof(*ipv6h);
1067         if (encap_limit >= 0) {
1068                 max_headroom += 8;
1069                 mtu -= 8;
1070         }
1071         if (mtu < IPV6_MIN_MTU)
1072                 mtu = IPV6_MIN_MTU;
1073         if (skb_dst(skb))
1074                 skb_dst(skb)->ops->update_pmtu(skb_dst(skb), NULL, skb, mtu);
1075         if (skb->len > mtu && !skb_is_gso(skb)) {
1076                 *pmtu = mtu;
1077                 err = -EMSGSIZE;
1078                 goto tx_err_dst_release;
1079         }
1080
1081         if (t->err_count > 0) {
1082                 if (time_before(jiffies,
1083                                 t->err_time + IP6TUNNEL_ERR_TIMEO)) {
1084                         t->err_count--;
1085
1086                         dst_link_failure(skb);
1087                 } else {
1088                         t->err_count = 0;
1089                 }
1090         }
1091
1092         skb_scrub_packet(skb, !net_eq(t->net, dev_net(dev)));
1093
1094         /*
1095          * Okay, now see if we can stuff it in the buffer as-is.
1096          */
1097         max_headroom += LL_RESERVED_SPACE(tdev);
1098
1099         if (skb_headroom(skb) < max_headroom || skb_shared(skb) ||
1100             (skb_cloned(skb) && !skb_clone_writable(skb, 0))) {
1101                 struct sk_buff *new_skb;
1102
1103                 new_skb = skb_realloc_headroom(skb, max_headroom);
1104                 if (!new_skb)
1105                         goto tx_err_dst_release;
1106
1107                 if (skb->sk)
1108                         skb_set_owner_w(new_skb, skb->sk);
1109                 consume_skb(skb);
1110                 skb = new_skb;
1111         }
1112
1113         if (!fl6->flowi6_mark && ndst)
1114                 dst_cache_set_ip6(&t->dst_cache, ndst, &fl6->saddr);
1115         skb_dst_set(skb, dst);
1116
1117         if (encap_limit >= 0) {
1118                 init_tel_txopt(&opt, encap_limit);
1119                 ipv6_push_nfrag_opts(skb, &opt.ops, &proto, NULL);
1120         }
1121
1122         if (likely(!skb->encapsulation)) {
1123                 skb_reset_inner_headers(skb);
1124                 skb->encapsulation = 1;
1125         }
1126
1127         max_headroom = LL_RESERVED_SPACE(dst->dev) + sizeof(struct ipv6hdr)
1128                         + dst->header_len;
1129         if (max_headroom > dev->needed_headroom)
1130                 dev->needed_headroom = max_headroom;
1131
1132         skb_push(skb, sizeof(struct ipv6hdr));
1133         skb_reset_network_header(skb);
1134         ipv6h = ipv6_hdr(skb);
1135         ip6_flow_hdr(ipv6h, INET_ECN_encapsulate(0, dsfield),
1136                      ip6_make_flowlabel(net, skb, fl6->flowlabel, true, fl6));
1137         ipv6h->hop_limit = t->parms.hop_limit;
1138         ipv6h->nexthdr = proto;
1139         ipv6h->saddr = fl6->saddr;
1140         ipv6h->daddr = fl6->daddr;
1141         ip6tunnel_xmit(NULL, skb, dev);
1142         return 0;
1143 tx_err_link_failure:
1144         stats->tx_carrier_errors++;
1145         dst_link_failure(skb);
1146 tx_err_dst_release:
1147         dst_release(dst);
1148         return err;
1149 }
1150 EXPORT_SYMBOL(ip6_tnl_xmit);
1151
1152 static inline int
1153 ip4ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev)
1154 {
1155         struct ip6_tnl *t = netdev_priv(dev);
1156         const struct iphdr  *iph = ip_hdr(skb);
1157         int encap_limit = -1;
1158         struct flowi6 fl6;
1159         __u8 dsfield;
1160         __u32 mtu;
1161         u8 tproto;
1162         int err;
1163
1164         memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
1165
1166         tproto = ACCESS_ONCE(t->parms.proto);
1167         if (tproto != IPPROTO_IPIP && tproto != 0)
1168                 return -1;
1169
1170         if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1171                 encap_limit = t->parms.encap_limit;
1172
1173         memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
1174
1175         dsfield = ipv4_get_dsfield(iph);
1176
1177         if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
1178                 fl6.flowlabel |= htonl((__u32)iph->tos << IPV6_TCLASS_SHIFT)
1179                                           & IPV6_TCLASS_MASK;
1180         if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
1181                 fl6.flowi6_mark = skb->mark;
1182
1183         err = ip6_tnl_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu,
1184                            IPPROTO_IPIP);
1185         if (err != 0) {
1186                 /* XXX: send ICMP error even if DF is not set. */
1187                 if (err == -EMSGSIZE)
1188                         icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
1189                                   htonl(mtu));
1190                 return -1;
1191         }
1192
1193         return 0;
1194 }
1195
1196 static inline int
1197 ip6ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev)
1198 {
1199         struct ip6_tnl *t = netdev_priv(dev);
1200         struct ipv6hdr *ipv6h = ipv6_hdr(skb);
1201         int encap_limit = -1;
1202         __u16 offset;
1203         struct flowi6 fl6;
1204         __u8 dsfield;
1205         __u32 mtu;
1206         u8 tproto;
1207         int err;
1208
1209         tproto = ACCESS_ONCE(t->parms.proto);
1210         if ((tproto != IPPROTO_IPV6 && tproto != 0) ||
1211             ip6_tnl_addr_conflict(t, ipv6h))
1212                 return -1;
1213
1214         offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb));
1215         if (offset > 0) {
1216                 struct ipv6_tlv_tnl_enc_lim *tel;
1217                 tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset];
1218                 if (tel->encap_limit == 0) {
1219                         icmpv6_send(skb, ICMPV6_PARAMPROB,
1220                                     ICMPV6_HDR_FIELD, offset + 2);
1221                         return -1;
1222                 }
1223                 encap_limit = tel->encap_limit - 1;
1224         } else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1225                 encap_limit = t->parms.encap_limit;
1226
1227         memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
1228
1229         dsfield = ipv6_get_dsfield(ipv6h);
1230         if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
1231                 fl6.flowlabel |= (*(__be32 *) ipv6h & IPV6_TCLASS_MASK);
1232         if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL)
1233                 fl6.flowlabel |= ip6_flowlabel(ipv6h);
1234         if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
1235                 fl6.flowi6_mark = skb->mark;
1236
1237         err = ip6_tnl_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu,
1238                            IPPROTO_IPV6);
1239         if (err != 0) {
1240                 if (err == -EMSGSIZE)
1241                         icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
1242                 return -1;
1243         }
1244
1245         return 0;
1246 }
1247
1248 static netdev_tx_t
1249 ip6_tnl_start_xmit(struct sk_buff *skb, struct net_device *dev)
1250 {
1251         struct ip6_tnl *t = netdev_priv(dev);
1252         struct net_device_stats *stats = &t->dev->stats;
1253         int ret;
1254
1255         switch (skb->protocol) {
1256         case htons(ETH_P_IP):
1257                 ret = ip4ip6_tnl_xmit(skb, dev);
1258                 break;
1259         case htons(ETH_P_IPV6):
1260                 ret = ip6ip6_tnl_xmit(skb, dev);
1261                 break;
1262         default:
1263                 goto tx_err;
1264         }
1265
1266         if (ret < 0)
1267                 goto tx_err;
1268
1269         return NETDEV_TX_OK;
1270
1271 tx_err:
1272         stats->tx_errors++;
1273         stats->tx_dropped++;
1274         kfree_skb(skb);
1275         return NETDEV_TX_OK;
1276 }
1277
1278 static void ip6_tnl_link_config(struct ip6_tnl *t)
1279 {
1280         struct net_device *dev = t->dev;
1281         struct __ip6_tnl_parm *p = &t->parms;
1282         struct flowi6 *fl6 = &t->fl.u.ip6;
1283
1284         memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr));
1285         memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr));
1286
1287         /* Set up flowi template */
1288         fl6->saddr = p->laddr;
1289         fl6->daddr = p->raddr;
1290         fl6->flowi6_oif = p->link;
1291         fl6->flowlabel = 0;
1292
1293         if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS))
1294                 fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo;
1295         if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL))
1296                 fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo;
1297
1298         p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET);
1299         p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr);
1300
1301         if (p->flags&IP6_TNL_F_CAP_XMIT && p->flags&IP6_TNL_F_CAP_RCV)
1302                 dev->flags |= IFF_POINTOPOINT;
1303         else
1304                 dev->flags &= ~IFF_POINTOPOINT;
1305
1306         if (p->flags & IP6_TNL_F_CAP_XMIT) {
1307                 int strict = (ipv6_addr_type(&p->raddr) &
1308                               (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL));
1309
1310                 struct rt6_info *rt = rt6_lookup(t->net,
1311                                                  &p->raddr, &p->laddr,
1312                                                  p->link, strict);
1313
1314                 if (!rt)
1315                         return;
1316
1317                 if (rt->dst.dev) {
1318                         dev->hard_header_len = rt->dst.dev->hard_header_len +
1319                                 sizeof(struct ipv6hdr);
1320
1321                         dev->mtu = rt->dst.dev->mtu - sizeof(struct ipv6hdr);
1322                         if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1323                                 dev->mtu -= 8;
1324
1325                         if (dev->mtu < IPV6_MIN_MTU)
1326                                 dev->mtu = IPV6_MIN_MTU;
1327                 }
1328                 ip6_rt_put(rt);
1329         }
1330 }
1331
1332 /**
1333  * ip6_tnl_change - update the tunnel parameters
1334  *   @t: tunnel to be changed
1335  *   @p: tunnel configuration parameters
1336  *
1337  * Description:
1338  *   ip6_tnl_change() updates the tunnel parameters
1339  **/
1340
1341 static int
1342 ip6_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p)
1343 {
1344         t->parms.laddr = p->laddr;
1345         t->parms.raddr = p->raddr;
1346         t->parms.flags = p->flags;
1347         t->parms.hop_limit = p->hop_limit;
1348         t->parms.encap_limit = p->encap_limit;
1349         t->parms.flowinfo = p->flowinfo;
1350         t->parms.link = p->link;
1351         t->parms.proto = p->proto;
1352         dst_cache_reset(&t->dst_cache);
1353         ip6_tnl_link_config(t);
1354         return 0;
1355 }
1356
1357 static int ip6_tnl_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p)
1358 {
1359         struct net *net = t->net;
1360         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1361         int err;
1362
1363         ip6_tnl_unlink(ip6n, t);
1364         synchronize_net();
1365         err = ip6_tnl_change(t, p);
1366         ip6_tnl_link(ip6n, t);
1367         netdev_state_change(t->dev);
1368         return err;
1369 }
1370
1371 static int ip6_tnl0_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p)
1372 {
1373         /* for default tnl0 device allow to change only the proto */
1374         t->parms.proto = p->proto;
1375         netdev_state_change(t->dev);
1376         return 0;
1377 }
1378
1379 static void
1380 ip6_tnl_parm_from_user(struct __ip6_tnl_parm *p, const struct ip6_tnl_parm *u)
1381 {
1382         p->laddr = u->laddr;
1383         p->raddr = u->raddr;
1384         p->flags = u->flags;
1385         p->hop_limit = u->hop_limit;
1386         p->encap_limit = u->encap_limit;
1387         p->flowinfo = u->flowinfo;
1388         p->link = u->link;
1389         p->proto = u->proto;
1390         memcpy(p->name, u->name, sizeof(u->name));
1391 }
1392
1393 static void
1394 ip6_tnl_parm_to_user(struct ip6_tnl_parm *u, const struct __ip6_tnl_parm *p)
1395 {
1396         u->laddr = p->laddr;
1397         u->raddr = p->raddr;
1398         u->flags = p->flags;
1399         u->hop_limit = p->hop_limit;
1400         u->encap_limit = p->encap_limit;
1401         u->flowinfo = p->flowinfo;
1402         u->link = p->link;
1403         u->proto = p->proto;
1404         memcpy(u->name, p->name, sizeof(u->name));
1405 }
1406
1407 /**
1408  * ip6_tnl_ioctl - configure ipv6 tunnels from userspace
1409  *   @dev: virtual device associated with tunnel
1410  *   @ifr: parameters passed from userspace
1411  *   @cmd: command to be performed
1412  *
1413  * Description:
1414  *   ip6_tnl_ioctl() is used for managing IPv6 tunnels
1415  *   from userspace.
1416  *
1417  *   The possible commands are the following:
1418  *     %SIOCGETTUNNEL: get tunnel parameters for device
1419  *     %SIOCADDTUNNEL: add tunnel matching given tunnel parameters
1420  *     %SIOCCHGTUNNEL: change tunnel parameters to those given
1421  *     %SIOCDELTUNNEL: delete tunnel
1422  *
1423  *   The fallback device "ip6tnl0", created during module
1424  *   initialization, can be used for creating other tunnel devices.
1425  *
1426  * Return:
1427  *   0 on success,
1428  *   %-EFAULT if unable to copy data to or from userspace,
1429  *   %-EPERM if current process hasn't %CAP_NET_ADMIN set
1430  *   %-EINVAL if passed tunnel parameters are invalid,
1431  *   %-EEXIST if changing a tunnel's parameters would cause a conflict
1432  *   %-ENODEV if attempting to change or delete a nonexisting device
1433  **/
1434
1435 static int
1436 ip6_tnl_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
1437 {
1438         int err = 0;
1439         struct ip6_tnl_parm p;
1440         struct __ip6_tnl_parm p1;
1441         struct ip6_tnl *t = netdev_priv(dev);
1442         struct net *net = t->net;
1443         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1444
1445         memset(&p1, 0, sizeof(p1));
1446
1447         switch (cmd) {
1448         case SIOCGETTUNNEL:
1449                 if (dev == ip6n->fb_tnl_dev) {
1450                         if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
1451                                 err = -EFAULT;
1452                                 break;
1453                         }
1454                         ip6_tnl_parm_from_user(&p1, &p);
1455                         t = ip6_tnl_locate(net, &p1, 0);
1456                         if (IS_ERR(t))
1457                                 t = netdev_priv(dev);
1458                 } else {
1459                         memset(&p, 0, sizeof(p));
1460                 }
1461                 ip6_tnl_parm_to_user(&p, &t->parms);
1462                 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) {
1463                         err = -EFAULT;
1464                 }
1465                 break;
1466         case SIOCADDTUNNEL:
1467         case SIOCCHGTUNNEL:
1468                 err = -EPERM;
1469                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1470                         break;
1471                 err = -EFAULT;
1472                 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
1473                         break;
1474                 err = -EINVAL;
1475                 if (p.proto != IPPROTO_IPV6 && p.proto != IPPROTO_IPIP &&
1476                     p.proto != 0)
1477                         break;
1478                 ip6_tnl_parm_from_user(&p1, &p);
1479                 t = ip6_tnl_locate(net, &p1, cmd == SIOCADDTUNNEL);
1480                 if (cmd == SIOCCHGTUNNEL) {
1481                         if (!IS_ERR(t)) {
1482                                 if (t->dev != dev) {
1483                                         err = -EEXIST;
1484                                         break;
1485                                 }
1486                         } else
1487                                 t = netdev_priv(dev);
1488                         if (dev == ip6n->fb_tnl_dev)
1489                                 err = ip6_tnl0_update(t, &p1);
1490                         else
1491                                 err = ip6_tnl_update(t, &p1);
1492                 }
1493                 if (!IS_ERR(t)) {
1494                         err = 0;
1495                         ip6_tnl_parm_to_user(&p, &t->parms);
1496                         if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
1497                                 err = -EFAULT;
1498
1499                 } else {
1500                         err = PTR_ERR(t);
1501                 }
1502                 break;
1503         case SIOCDELTUNNEL:
1504                 err = -EPERM;
1505                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1506                         break;
1507
1508                 if (dev == ip6n->fb_tnl_dev) {
1509                         err = -EFAULT;
1510                         if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
1511                                 break;
1512                         err = -ENOENT;
1513                         ip6_tnl_parm_from_user(&p1, &p);
1514                         t = ip6_tnl_locate(net, &p1, 0);
1515                         if (IS_ERR(t))
1516                                 break;
1517                         err = -EPERM;
1518                         if (t->dev == ip6n->fb_tnl_dev)
1519                                 break;
1520                         dev = t->dev;
1521                 }
1522                 err = 0;
1523                 unregister_netdevice(dev);
1524                 break;
1525         default:
1526                 err = -EINVAL;
1527         }
1528         return err;
1529 }
1530
1531 /**
1532  * ip6_tnl_change_mtu - change mtu manually for tunnel device
1533  *   @dev: virtual device associated with tunnel
1534  *   @new_mtu: the new mtu
1535  *
1536  * Return:
1537  *   0 on success,
1538  *   %-EINVAL if mtu too small
1539  **/
1540
1541 int ip6_tnl_change_mtu(struct net_device *dev, int new_mtu)
1542 {
1543         struct ip6_tnl *tnl = netdev_priv(dev);
1544
1545         if (tnl->parms.proto == IPPROTO_IPIP) {
1546                 if (new_mtu < 68)
1547                         return -EINVAL;
1548         } else {
1549                 if (new_mtu < IPV6_MIN_MTU)
1550                         return -EINVAL;
1551         }
1552         if (new_mtu > 0xFFF8 - dev->hard_header_len)
1553                 return -EINVAL;
1554         dev->mtu = new_mtu;
1555         return 0;
1556 }
1557 EXPORT_SYMBOL(ip6_tnl_change_mtu);
1558
1559 int ip6_tnl_get_iflink(const struct net_device *dev)
1560 {
1561         struct ip6_tnl *t = netdev_priv(dev);
1562
1563         return t->parms.link;
1564 }
1565 EXPORT_SYMBOL(ip6_tnl_get_iflink);
1566
1567 static const struct net_device_ops ip6_tnl_netdev_ops = {
1568         .ndo_init       = ip6_tnl_dev_init,
1569         .ndo_uninit     = ip6_tnl_dev_uninit,
1570         .ndo_start_xmit = ip6_tnl_start_xmit,
1571         .ndo_do_ioctl   = ip6_tnl_ioctl,
1572         .ndo_change_mtu = ip6_tnl_change_mtu,
1573         .ndo_get_stats  = ip6_get_stats,
1574         .ndo_get_iflink = ip6_tnl_get_iflink,
1575 };
1576
1577
1578 /**
1579  * ip6_tnl_dev_setup - setup virtual tunnel device
1580  *   @dev: virtual device associated with tunnel
1581  *
1582  * Description:
1583  *   Initialize function pointers and device parameters
1584  **/
1585
1586 static void ip6_tnl_dev_setup(struct net_device *dev)
1587 {
1588         struct ip6_tnl *t;
1589
1590         dev->netdev_ops = &ip6_tnl_netdev_ops;
1591         dev->destructor = ip6_dev_free;
1592
1593         dev->type = ARPHRD_TUNNEL6;
1594         dev->hard_header_len = LL_MAX_HEADER + sizeof(struct ipv6hdr);
1595         dev->mtu = ETH_DATA_LEN - sizeof(struct ipv6hdr);
1596         t = netdev_priv(dev);
1597         if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1598                 dev->mtu -= 8;
1599         dev->flags |= IFF_NOARP;
1600         dev->addr_len = sizeof(struct in6_addr);
1601         netif_keep_dst(dev);
1602         /* This perm addr will be used as interface identifier by IPv6 */
1603         dev->addr_assign_type = NET_ADDR_RANDOM;
1604         eth_random_addr(dev->perm_addr);
1605 }
1606
1607
1608 /**
1609  * ip6_tnl_dev_init_gen - general initializer for all tunnel devices
1610  *   @dev: virtual device associated with tunnel
1611  **/
1612
1613 static inline int
1614 ip6_tnl_dev_init_gen(struct net_device *dev)
1615 {
1616         struct ip6_tnl *t = netdev_priv(dev);
1617         int ret;
1618
1619         t->dev = dev;
1620         t->net = dev_net(dev);
1621         dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1622         if (!dev->tstats)
1623                 return -ENOMEM;
1624
1625         ret = dst_cache_init(&t->dst_cache, GFP_KERNEL);
1626         if (ret)
1627                 goto free_stats;
1628
1629         ret = gro_cells_init(&t->gro_cells, dev);
1630         if (ret)
1631                 goto destroy_dst;
1632
1633         t->hlen = 0;
1634         t->tun_hlen = 0;
1635
1636         return 0;
1637
1638 destroy_dst:
1639         dst_cache_destroy(&t->dst_cache);
1640 free_stats:
1641         free_percpu(dev->tstats);
1642         dev->tstats = NULL;
1643
1644         return ret;
1645 }
1646
1647 /**
1648  * ip6_tnl_dev_init - initializer for all non fallback tunnel devices
1649  *   @dev: virtual device associated with tunnel
1650  **/
1651
1652 static int ip6_tnl_dev_init(struct net_device *dev)
1653 {
1654         struct ip6_tnl *t = netdev_priv(dev);
1655         int err = ip6_tnl_dev_init_gen(dev);
1656
1657         if (err)
1658                 return err;
1659         ip6_tnl_link_config(t);
1660         return 0;
1661 }
1662
1663 /**
1664  * ip6_fb_tnl_dev_init - initializer for fallback tunnel device
1665  *   @dev: fallback device
1666  *
1667  * Return: 0
1668  **/
1669
1670 static int __net_init ip6_fb_tnl_dev_init(struct net_device *dev)
1671 {
1672         struct ip6_tnl *t = netdev_priv(dev);
1673         struct net *net = dev_net(dev);
1674         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1675
1676         t->parms.proto = IPPROTO_IPV6;
1677         dev_hold(dev);
1678
1679         rcu_assign_pointer(ip6n->tnls_wc[0], t);
1680         return 0;
1681 }
1682
1683 static int ip6_tnl_validate(struct nlattr *tb[], struct nlattr *data[])
1684 {
1685         u8 proto;
1686
1687         if (!data || !data[IFLA_IPTUN_PROTO])
1688                 return 0;
1689
1690         proto = nla_get_u8(data[IFLA_IPTUN_PROTO]);
1691         if (proto != IPPROTO_IPV6 &&
1692             proto != IPPROTO_IPIP &&
1693             proto != 0)
1694                 return -EINVAL;
1695
1696         return 0;
1697 }
1698
1699 static void ip6_tnl_netlink_parms(struct nlattr *data[],
1700                                   struct __ip6_tnl_parm *parms)
1701 {
1702         memset(parms, 0, sizeof(*parms));
1703
1704         if (!data)
1705                 return;
1706
1707         if (data[IFLA_IPTUN_LINK])
1708                 parms->link = nla_get_u32(data[IFLA_IPTUN_LINK]);
1709
1710         if (data[IFLA_IPTUN_LOCAL])
1711                 parms->laddr = nla_get_in6_addr(data[IFLA_IPTUN_LOCAL]);
1712
1713         if (data[IFLA_IPTUN_REMOTE])
1714                 parms->raddr = nla_get_in6_addr(data[IFLA_IPTUN_REMOTE]);
1715
1716         if (data[IFLA_IPTUN_TTL])
1717                 parms->hop_limit = nla_get_u8(data[IFLA_IPTUN_TTL]);
1718
1719         if (data[IFLA_IPTUN_ENCAP_LIMIT])
1720                 parms->encap_limit = nla_get_u8(data[IFLA_IPTUN_ENCAP_LIMIT]);
1721
1722         if (data[IFLA_IPTUN_FLOWINFO])
1723                 parms->flowinfo = nla_get_be32(data[IFLA_IPTUN_FLOWINFO]);
1724
1725         if (data[IFLA_IPTUN_FLAGS])
1726                 parms->flags = nla_get_u32(data[IFLA_IPTUN_FLAGS]);
1727
1728         if (data[IFLA_IPTUN_PROTO])
1729                 parms->proto = nla_get_u8(data[IFLA_IPTUN_PROTO]);
1730 }
1731
1732 static int ip6_tnl_newlink(struct net *src_net, struct net_device *dev,
1733                            struct nlattr *tb[], struct nlattr *data[])
1734 {
1735         struct net *net = dev_net(dev);
1736         struct ip6_tnl *nt, *t;
1737
1738         nt = netdev_priv(dev);
1739         ip6_tnl_netlink_parms(data, &nt->parms);
1740
1741         t = ip6_tnl_locate(net, &nt->parms, 0);
1742         if (!IS_ERR(t))
1743                 return -EEXIST;
1744
1745         return ip6_tnl_create2(dev);
1746 }
1747
1748 static int ip6_tnl_changelink(struct net_device *dev, struct nlattr *tb[],
1749                               struct nlattr *data[])
1750 {
1751         struct ip6_tnl *t = netdev_priv(dev);
1752         struct __ip6_tnl_parm p;
1753         struct net *net = t->net;
1754         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1755
1756         if (dev == ip6n->fb_tnl_dev)
1757                 return -EINVAL;
1758
1759         ip6_tnl_netlink_parms(data, &p);
1760
1761         t = ip6_tnl_locate(net, &p, 0);
1762         if (!IS_ERR(t)) {
1763                 if (t->dev != dev)
1764                         return -EEXIST;
1765         } else
1766                 t = netdev_priv(dev);
1767
1768         return ip6_tnl_update(t, &p);
1769 }
1770
1771 static void ip6_tnl_dellink(struct net_device *dev, struct list_head *head)
1772 {
1773         struct net *net = dev_net(dev);
1774         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1775
1776         if (dev != ip6n->fb_tnl_dev)
1777                 unregister_netdevice_queue(dev, head);
1778 }
1779
1780 static size_t ip6_tnl_get_size(const struct net_device *dev)
1781 {
1782         return
1783                 /* IFLA_IPTUN_LINK */
1784                 nla_total_size(4) +
1785                 /* IFLA_IPTUN_LOCAL */
1786                 nla_total_size(sizeof(struct in6_addr)) +
1787                 /* IFLA_IPTUN_REMOTE */
1788                 nla_total_size(sizeof(struct in6_addr)) +
1789                 /* IFLA_IPTUN_TTL */
1790                 nla_total_size(1) +
1791                 /* IFLA_IPTUN_ENCAP_LIMIT */
1792                 nla_total_size(1) +
1793                 /* IFLA_IPTUN_FLOWINFO */
1794                 nla_total_size(4) +
1795                 /* IFLA_IPTUN_FLAGS */
1796                 nla_total_size(4) +
1797                 /* IFLA_IPTUN_PROTO */
1798                 nla_total_size(1) +
1799                 0;
1800 }
1801
1802 static int ip6_tnl_fill_info(struct sk_buff *skb, const struct net_device *dev)
1803 {
1804         struct ip6_tnl *tunnel = netdev_priv(dev);
1805         struct __ip6_tnl_parm *parm = &tunnel->parms;
1806
1807         if (nla_put_u32(skb, IFLA_IPTUN_LINK, parm->link) ||
1808             nla_put_in6_addr(skb, IFLA_IPTUN_LOCAL, &parm->laddr) ||
1809             nla_put_in6_addr(skb, IFLA_IPTUN_REMOTE, &parm->raddr) ||
1810             nla_put_u8(skb, IFLA_IPTUN_TTL, parm->hop_limit) ||
1811             nla_put_u8(skb, IFLA_IPTUN_ENCAP_LIMIT, parm->encap_limit) ||
1812             nla_put_be32(skb, IFLA_IPTUN_FLOWINFO, parm->flowinfo) ||
1813             nla_put_u32(skb, IFLA_IPTUN_FLAGS, parm->flags) ||
1814             nla_put_u8(skb, IFLA_IPTUN_PROTO, parm->proto))
1815                 goto nla_put_failure;
1816         return 0;
1817
1818 nla_put_failure:
1819         return -EMSGSIZE;
1820 }
1821
1822 struct net *ip6_tnl_get_link_net(const struct net_device *dev)
1823 {
1824         struct ip6_tnl *tunnel = netdev_priv(dev);
1825
1826         return tunnel->net;
1827 }
1828 EXPORT_SYMBOL(ip6_tnl_get_link_net);
1829
1830 static const struct nla_policy ip6_tnl_policy[IFLA_IPTUN_MAX + 1] = {
1831         [IFLA_IPTUN_LINK]               = { .type = NLA_U32 },
1832         [IFLA_IPTUN_LOCAL]              = { .len = sizeof(struct in6_addr) },
1833         [IFLA_IPTUN_REMOTE]             = { .len = sizeof(struct in6_addr) },
1834         [IFLA_IPTUN_TTL]                = { .type = NLA_U8 },
1835         [IFLA_IPTUN_ENCAP_LIMIT]        = { .type = NLA_U8 },
1836         [IFLA_IPTUN_FLOWINFO]           = { .type = NLA_U32 },
1837         [IFLA_IPTUN_FLAGS]              = { .type = NLA_U32 },
1838         [IFLA_IPTUN_PROTO]              = { .type = NLA_U8 },
1839 };
1840
1841 static struct rtnl_link_ops ip6_link_ops __read_mostly = {
1842         .kind           = "ip6tnl",
1843         .maxtype        = IFLA_IPTUN_MAX,
1844         .policy         = ip6_tnl_policy,
1845         .priv_size      = sizeof(struct ip6_tnl),
1846         .setup          = ip6_tnl_dev_setup,
1847         .validate       = ip6_tnl_validate,
1848         .newlink        = ip6_tnl_newlink,
1849         .changelink     = ip6_tnl_changelink,
1850         .dellink        = ip6_tnl_dellink,
1851         .get_size       = ip6_tnl_get_size,
1852         .fill_info      = ip6_tnl_fill_info,
1853         .get_link_net   = ip6_tnl_get_link_net,
1854 };
1855
1856 static struct xfrm6_tunnel ip4ip6_handler __read_mostly = {
1857         .handler        = ip4ip6_rcv,
1858         .err_handler    = ip4ip6_err,
1859         .priority       =       1,
1860 };
1861
1862 static struct xfrm6_tunnel ip6ip6_handler __read_mostly = {
1863         .handler        = ip6ip6_rcv,
1864         .err_handler    = ip6ip6_err,
1865         .priority       =       1,
1866 };
1867
1868 static void __net_exit ip6_tnl_destroy_tunnels(struct net *net)
1869 {
1870         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1871         struct net_device *dev, *aux;
1872         int h;
1873         struct ip6_tnl *t;
1874         LIST_HEAD(list);
1875
1876         for_each_netdev_safe(net, dev, aux)
1877                 if (dev->rtnl_link_ops == &ip6_link_ops)
1878                         unregister_netdevice_queue(dev, &list);
1879
1880         for (h = 0; h < HASH_SIZE; h++) {
1881                 t = rtnl_dereference(ip6n->tnls_r_l[h]);
1882                 while (t) {
1883                         /* If dev is in the same netns, it has already
1884                          * been added to the list by the previous loop.
1885                          */
1886                         if (!net_eq(dev_net(t->dev), net))
1887                                 unregister_netdevice_queue(t->dev, &list);
1888                         t = rtnl_dereference(t->next);
1889                 }
1890         }
1891
1892         unregister_netdevice_many(&list);
1893 }
1894
1895 static int __net_init ip6_tnl_init_net(struct net *net)
1896 {
1897         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1898         struct ip6_tnl *t = NULL;
1899         int err;
1900
1901         ip6n->tnls[0] = ip6n->tnls_wc;
1902         ip6n->tnls[1] = ip6n->tnls_r_l;
1903
1904         err = -ENOMEM;
1905         ip6n->fb_tnl_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6tnl0",
1906                                         NET_NAME_UNKNOWN, ip6_tnl_dev_setup);
1907
1908         if (!ip6n->fb_tnl_dev)
1909                 goto err_alloc_dev;
1910         dev_net_set(ip6n->fb_tnl_dev, net);
1911         ip6n->fb_tnl_dev->rtnl_link_ops = &ip6_link_ops;
1912         /* FB netdevice is special: we have one, and only one per netns.
1913          * Allowing to move it to another netns is clearly unsafe.
1914          */
1915         ip6n->fb_tnl_dev->features |= NETIF_F_NETNS_LOCAL;
1916
1917         err = ip6_fb_tnl_dev_init(ip6n->fb_tnl_dev);
1918         if (err < 0)
1919                 goto err_register;
1920
1921         err = register_netdev(ip6n->fb_tnl_dev);
1922         if (err < 0)
1923                 goto err_register;
1924
1925         t = netdev_priv(ip6n->fb_tnl_dev);
1926
1927         strcpy(t->parms.name, ip6n->fb_tnl_dev->name);
1928         return 0;
1929
1930 err_register:
1931         ip6_dev_free(ip6n->fb_tnl_dev);
1932 err_alloc_dev:
1933         return err;
1934 }
1935
1936 static void __net_exit ip6_tnl_exit_net(struct net *net)
1937 {
1938         rtnl_lock();
1939         ip6_tnl_destroy_tunnels(net);
1940         rtnl_unlock();
1941 }
1942
1943 static struct pernet_operations ip6_tnl_net_ops = {
1944         .init = ip6_tnl_init_net,
1945         .exit = ip6_tnl_exit_net,
1946         .id   = &ip6_tnl_net_id,
1947         .size = sizeof(struct ip6_tnl_net),
1948 };
1949
1950 /**
1951  * ip6_tunnel_init - register protocol and reserve needed resources
1952  *
1953  * Return: 0 on success
1954  **/
1955
1956 static int __init ip6_tunnel_init(void)
1957 {
1958         int  err;
1959
1960         err = register_pernet_device(&ip6_tnl_net_ops);
1961         if (err < 0)
1962                 goto out_pernet;
1963
1964         err = xfrm6_tunnel_register(&ip4ip6_handler, AF_INET);
1965         if (err < 0) {
1966                 pr_err("%s: can't register ip4ip6\n", __func__);
1967                 goto out_ip4ip6;
1968         }
1969
1970         err = xfrm6_tunnel_register(&ip6ip6_handler, AF_INET6);
1971         if (err < 0) {
1972                 pr_err("%s: can't register ip6ip6\n", __func__);
1973                 goto out_ip6ip6;
1974         }
1975         err = rtnl_link_register(&ip6_link_ops);
1976         if (err < 0)
1977                 goto rtnl_link_failed;
1978
1979         return 0;
1980
1981 rtnl_link_failed:
1982         xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6);
1983 out_ip6ip6:
1984         xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET);
1985 out_ip4ip6:
1986         unregister_pernet_device(&ip6_tnl_net_ops);
1987 out_pernet:
1988         return err;
1989 }
1990
1991 /**
1992  * ip6_tunnel_cleanup - free resources and unregister protocol
1993  **/
1994
1995 static void __exit ip6_tunnel_cleanup(void)
1996 {
1997         rtnl_link_unregister(&ip6_link_ops);
1998         if (xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET))
1999                 pr_info("%s: can't deregister ip4ip6\n", __func__);
2000
2001         if (xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6))
2002                 pr_info("%s: can't deregister ip6ip6\n", __func__);
2003
2004         unregister_pernet_device(&ip6_tnl_net_ops);
2005 }
2006
2007 module_init(ip6_tunnel_init);
2008 module_exit(ip6_tunnel_cleanup);