Pileus Git - ~andy/linux/blob - 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_NETDEV("ip6tnl0");
  65
  66 #ifdef IP6_TNL_DEBUG
  67 #define IP6_TNL_TRACE(x...) pr_debug("%s:" x "\n", __func__)
  68 #else
  69 #define IP6_TNL_TRACE(x...) do {;} while(0)
  70 #endif
  71
  72 #define IPV6_TCLASS_SHIFT 20
  73
  74 #define HASH_SIZE_SHIFT  5
  75 #define HASH_SIZE (1 << HASH_SIZE_SHIFT)
  76
  77 static bool log_ecn_error = true;
  78 module_param(log_ecn_error, bool, 0644);
  79 MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");
  80
  81 static u32 HASH(const struct in6_addr *addr1, const struct in6_addr *addr2)
  82 {
  83         u32 hash = ipv6_addr_hash(addr1) ^ ipv6_addr_hash(addr2);
  84
  85         return hash_32(hash, HASH_SIZE_SHIFT);
  86 }
  87
  88 static int ip6_tnl_dev_init(struct net_device *dev);
  89 static void ip6_tnl_dev_setup(struct net_device *dev);
  90 static struct rtnl_link_ops ip6_link_ops __read_mostly;
  91
  92 static int ip6_tnl_net_id __read_mostly;
  93 struct ip6_tnl_net {
  94         /* the IPv6 tunnel fallback device */
  95         struct net_device *fb_tnl_dev;
  96         /* lists for storing tunnels in use */
  97         struct ip6_tnl __rcu *tnls_r_l[HASH_SIZE];
  98         struct ip6_tnl __rcu *tnls_wc[1];
  99         struct ip6_tnl __rcu **tnls[2];
 100 };
 101
 102 static struct net_device_stats *ip6_get_stats(struct net_device *dev)
 103 {
 104         struct pcpu_sw_netstats tmp, sum = { 0 };
 105         int i;
 106
 107         for_each_possible_cpu(i) {
 108                 unsigned int start;
 109                 const struct pcpu_sw_netstats *tstats =
 110                                                    per_cpu_ptr(dev->tstats, i);
 111
 112                 do {
 113                         start = u64_stats_fetch_begin_bh(&tstats->syncp);
 114                         tmp.rx_packets = tstats->rx_packets;
 115                         tmp.rx_bytes = tstats->rx_bytes;
 116                         tmp.tx_packets = tstats->tx_packets;
 117                         tmp.tx_bytes =  tstats->tx_bytes;
 118                 } while (u64_stats_fetch_retry_bh(&tstats->syncp, start));
 119
 120                 sum.rx_packets += tmp.rx_packets;
 121                 sum.rx_bytes   += tmp.rx_bytes;
 122                 sum.tx_packets += tmp.tx_packets;
 123                 sum.tx_bytes   += tmp.tx_bytes;
 124         }
 125         dev->stats.rx_packets = sum.rx_packets;
 126         dev->stats.rx_bytes   = sum.rx_bytes;
 127         dev->stats.tx_packets = sum.tx_packets;
 128         dev->stats.tx_bytes   = sum.tx_bytes;
 129         return &dev->stats;
 130 }
 131
 132 /*
 133  * Locking : hash tables are protected by RCU and RTNL
 134  */
 135
 136 struct dst_entry *ip6_tnl_dst_check(struct ip6_tnl *t)
 137 {
 138         struct dst_entry *dst = t->dst_cache;
 139
 140         if (dst && dst->obsolete &&
 141             dst->ops->check(dst, t->dst_cookie) == NULL) {
 142                 t->dst_cache = NULL;
 143                 dst_release(dst);
 144                 return NULL;
 145         }
 146
 147         return dst;
 148 }
 149 EXPORT_SYMBOL_GPL(ip6_tnl_dst_check);
 150
 151 void ip6_tnl_dst_reset(struct ip6_tnl *t)
 152 {
 153         dst_release(t->dst_cache);
 154         t->dst_cache = NULL;
 155 }
 156 EXPORT_SYMBOL_GPL(ip6_tnl_dst_reset);
 157
 158 void ip6_tnl_dst_store(struct ip6_tnl *t, struct dst_entry *dst)
 159 {
 160         struct rt6_info *rt = (struct rt6_info *) dst;
 161         t->dst_cookie = rt->rt6i_node ? rt->rt6i_node->fn_sernum : 0;
 162         dst_release(t->dst_cache);
 163         t->dst_cache = dst;
 164 }
 165 EXPORT_SYMBOL_GPL(ip6_tnl_dst_store);
 166
 167 /**
 168  * ip6_tnl_lookup - fetch tunnel matching the end-point addresses
 169  *   @remote: the address of the tunnel exit-point
 170  *   @local: the address of the tunnel entry-point
 171  *
 172  * Return:
 173  *   tunnel matching given end-points if found,
 174  *   else fallback tunnel if its device is up,
 175  *   else %NULL
 176  **/
 177
 178 #define for_each_ip6_tunnel_rcu(start) \
 179         for (t = rcu_dereference(start); t; t = rcu_dereference(t->next))
 180
 181 static struct ip6_tnl *
 182 ip6_tnl_lookup(struct net *net, const struct in6_addr *remote, const struct in6_addr *local)
 183 {
 184         unsigned int hash = HASH(remote, local);
 185         struct ip6_tnl *t;
 186         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
 187
 188         for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
 189                 if (ipv6_addr_equal(local, &t->parms.laddr) &&
 190                     ipv6_addr_equal(remote, &t->parms.raddr) &&
 191                     (t->dev->flags & IFF_UP))
 192                         return t;
 193         }
 194         t = rcu_dereference(ip6n->tnls_wc[0]);
 195         if (t && (t->dev->flags & IFF_UP))
 196                 return t;
 197
 198         return NULL;
 199 }
 200
 201 /**
 202  * ip6_tnl_bucket - get head of list matching given tunnel parameters
 203  *   @p: parameters containing tunnel end-points
 204  *
 205  * Description:
 206  *   ip6_tnl_bucket() returns the head of the list matching the
 207  *   &struct in6_addr entries laddr and raddr in @p.
 208  *
 209  * Return: head of IPv6 tunnel list
 210  **/
 211
 212 static struct ip6_tnl __rcu **
 213 ip6_tnl_bucket(struct ip6_tnl_net *ip6n, const struct __ip6_tnl_parm *p)
 214 {
 215         const struct in6_addr *remote = &p->raddr;
 216         const struct in6_addr *local = &p->laddr;
 217         unsigned int h = 0;
 218         int prio = 0;
 219
 220         if (!ipv6_addr_any(remote) || !ipv6_addr_any(local)) {
 221                 prio = 1;
 222                 h = HASH(remote, local);
 223         }
 224         return &ip6n->tnls[prio][h];
 225 }
 226
 227 /**
 228  * ip6_tnl_link - add tunnel to hash table
 229  *   @t: tunnel to be added
 230  **/
 231
 232 static void
 233 ip6_tnl_link(struct ip6_tnl_net *ip6n, struct ip6_tnl *t)
 234 {
 235         struct ip6_tnl __rcu **tp = ip6_tnl_bucket(ip6n, &t->parms);
 236
 237         rcu_assign_pointer(t->next , rtnl_dereference(*tp));
 238         rcu_assign_pointer(*tp, t);
 239 }
 240
 241 /**
 242  * ip6_tnl_unlink - remove tunnel from hash table
 243  *   @t: tunnel to be removed
 244  **/
 245
 246 static void
 247 ip6_tnl_unlink(struct ip6_tnl_net *ip6n, struct ip6_tnl *t)
 248 {
 249         struct ip6_tnl __rcu **tp;
 250         struct ip6_tnl *iter;
 251
 252         for (tp = ip6_tnl_bucket(ip6n, &t->parms);
 253              (iter = rtnl_dereference(*tp)) != NULL;
 254              tp = &iter->next) {
 255                 if (t == iter) {
 256                         rcu_assign_pointer(*tp, t->next);
 257                         break;
 258                 }
 259         }
 260 }
 261
 262 static void ip6_dev_free(struct net_device *dev)
 263 {
 264         free_percpu(dev->tstats);
 265         free_netdev(dev);
 266 }
 267
 268 static int ip6_tnl_create2(struct net_device *dev)
 269 {
 270         struct ip6_tnl *t = netdev_priv(dev);
 271         struct net *net = dev_net(dev);
 272         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
 273         int err;
 274
 275         t = netdev_priv(dev);
 276         err = ip6_tnl_dev_init(dev);
 277         if (err < 0)
 278                 goto out;
 279
 280         err = register_netdevice(dev);
 281         if (err < 0)
 282                 goto out;
 283
 284         strcpy(t->parms.name, dev->name);
 285         dev->rtnl_link_ops = &ip6_link_ops;
 286
 287         dev_hold(dev);
 288         ip6_tnl_link(ip6n, t);
 289         return 0;
 290
 291 out:
 292         return err;
 293 }
 294
 295 /**
 296  * ip6_tnl_create - create a new tunnel
 297  *   @p: tunnel parameters
 298  *   @pt: pointer to new tunnel
 299  *
 300  * Description:
 301  *   Create tunnel matching given parameters.
 302  *
 303  * Return:
 304  *   created tunnel or NULL
 305  **/
 306
 307 static struct ip6_tnl *ip6_tnl_create(struct net *net, struct __ip6_tnl_parm *p)
 308 {
 309         struct net_device *dev;
 310         struct ip6_tnl *t;
 311         char name[IFNAMSIZ];
 312         int err;
 313
 314         if (p->name[0])
 315                 strlcpy(name, p->name, IFNAMSIZ);
 316         else
 317                 sprintf(name, "ip6tnl%%d");
 318
 319         dev = alloc_netdev(sizeof (*t), name, ip6_tnl_dev_setup);
 320         if (dev == NULL)
 321                 goto failed;
 322
 323         dev_net_set(dev, net);
 324
 325         t = netdev_priv(dev);
 326         t->parms = *p;
 327         t->net = dev_net(dev);
 328         err = ip6_tnl_create2(dev);
 329         if (err < 0)
 330                 goto failed_free;
 331
 332         return t;
 333
 334 failed_free:
 335         ip6_dev_free(dev);
 336 failed:
 337         return NULL;
 338 }
 339
 340 /**
 341  * ip6_tnl_locate - find or create tunnel matching given parameters
 342  *   @p: tunnel parameters
 343  *   @create: != 0 if allowed to create new tunnel if no match found
 344  *
 345  * Description:
 346  *   ip6_tnl_locate() first tries to locate an existing tunnel
 347  *   based on @parms. If this is unsuccessful, but @create is set a new
 348  *   tunnel device is created and registered for use.
 349  *
 350  * Return:
 351  *   matching tunnel or NULL
 352  **/
 353
 354 static struct ip6_tnl *ip6_tnl_locate(struct net *net,
 355                 struct __ip6_tnl_parm *p, int create)
 356 {
 357         const struct in6_addr *remote = &p->raddr;
 358         const struct in6_addr *local = &p->laddr;
 359         struct ip6_tnl __rcu **tp;
 360         struct ip6_tnl *t;
 361         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
 362
 363         for (tp = ip6_tnl_bucket(ip6n, p);
 364              (t = rtnl_dereference(*tp)) != NULL;
 365              tp = &t->next) {
 366                 if (ipv6_addr_equal(local, &t->parms.laddr) &&
 367                     ipv6_addr_equal(remote, &t->parms.raddr))
 368                         return t;
 369         }
 370         if (!create)
 371                 return NULL;
 372         return ip6_tnl_create(net, p);
 373 }
 374
 375 /**
 376  * ip6_tnl_dev_uninit - tunnel device uninitializer
 377  *   @dev: the device to be destroyed
 378  *
 379  * Description:
 380  *   ip6_tnl_dev_uninit() removes tunnel from its list
 381  **/
 382
 383 static void
 384 ip6_tnl_dev_uninit(struct net_device *dev)
 385 {
 386         struct ip6_tnl *t = netdev_priv(dev);
 387         struct net *net = t->net;
 388         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
 389
 390         if (dev == ip6n->fb_tnl_dev)
 391                 RCU_INIT_POINTER(ip6n->tnls_wc[0], NULL);
 392         else
 393                 ip6_tnl_unlink(ip6n, t);
 394         ip6_tnl_dst_reset(t);
 395         dev_put(dev);
 396 }
 397
 398 /**
 399  * parse_tvl_tnl_enc_lim - handle encapsulation limit option
 400  *   @skb: received socket buffer
 401  *
 402  * Return:
 403  *   0 if none was found,
 404  *   else index to encapsulation limit
 405  **/
 406
 407 __u16 ip6_tnl_parse_tlv_enc_lim(struct sk_buff *skb, __u8 *raw)
 408 {
 409         const struct ipv6hdr *ipv6h = (const struct ipv6hdr *) raw;
 410         __u8 nexthdr = ipv6h->nexthdr;
 411         __u16 off = sizeof (*ipv6h);
 412
 413         while (ipv6_ext_hdr(nexthdr) && nexthdr != NEXTHDR_NONE) {
 414                 __u16 optlen = 0;
 415                 struct ipv6_opt_hdr *hdr;
 416                 if (raw + off + sizeof (*hdr) > skb->data &&
 417                     !pskb_may_pull(skb, raw - skb->data + off + sizeof (*hdr)))
 418                         break;
 419
 420                 hdr = (struct ipv6_opt_hdr *) (raw + off);
 421                 if (nexthdr == NEXTHDR_FRAGMENT) {
 422                         struct frag_hdr *frag_hdr = (struct frag_hdr *) hdr;
 423                         if (frag_hdr->frag_off)
 424                                 break;
 425                         optlen = 8;
 426                 } else if (nexthdr == NEXTHDR_AUTH) {
 427                         optlen = (hdr->hdrlen + 2) << 2;
 428                 } else {
 429                         optlen = ipv6_optlen(hdr);
 430                 }
 431                 if (nexthdr == NEXTHDR_DEST) {
 432                         __u16 i = off + 2;
 433                         while (1) {
 434                                 struct ipv6_tlv_tnl_enc_lim *tel;
 435
 436                                 /* No more room for encapsulation limit */
 437                                 if (i + sizeof (*tel) > off + optlen)
 438                                         break;
 439
 440                                 tel = (struct ipv6_tlv_tnl_enc_lim *) &raw[i];
 441                                 /* return index of option if found and valid */
 442                                 if (tel->type == IPV6_TLV_TNL_ENCAP_LIMIT &&
 443                                     tel->length == 1)
 444                                         return i;
 445                                 /* else jump to next option */
 446                                 if (tel->type)
 447                                         i += tel->length + 2;
 448                                 else
 449                                         i++;
 450                         }
 451                 }
 452                 nexthdr = hdr->nexthdr;
 453                 off += optlen;
 454         }
 455         return 0;
 456 }
 457 EXPORT_SYMBOL(ip6_tnl_parse_tlv_enc_lim);
 458
 459 /**
 460  * ip6_tnl_err - tunnel error handler
 461  *
 462  * Description:
 463  *   ip6_tnl_err() should handle errors in the tunnel according
 464  *   to the specifications in RFC 2473.
 465  **/
 466
 467 static int
 468 ip6_tnl_err(struct sk_buff *skb, __u8 ipproto, struct inet6_skb_parm *opt,
 469             u8 *type, u8 *code, int *msg, __u32 *info, int offset)
 470 {
 471         const struct ipv6hdr *ipv6h = (const struct ipv6hdr *) skb->data;
 472         struct ip6_tnl *t;
 473         int rel_msg = 0;
 474         u8 rel_type = ICMPV6_DEST_UNREACH;
 475         u8 rel_code = ICMPV6_ADDR_UNREACH;
 476         __u32 rel_info = 0;
 477         __u16 len;
 478         int err = -ENOENT;
 479
 480         /* If the packet doesn't contain the original IPv6 header we are
 481            in trouble since we might need the source address for further
 482            processing of the error. */
 483
 484         rcu_read_lock();
 485         if ((t = ip6_tnl_lookup(dev_net(skb->dev), &ipv6h->daddr,
 486                                         &ipv6h->saddr)) == NULL)
 487                 goto out;
 488
 489         if (t->parms.proto != ipproto && t->parms.proto != 0)
 490                 goto out;
 491
 492         err = 0;
 493
 494         switch (*type) {
 495                 __u32 teli;
 496                 struct ipv6_tlv_tnl_enc_lim *tel;
 497                 __u32 mtu;
 498         case ICMPV6_DEST_UNREACH:
 499                 net_warn_ratelimited("%s: Path to destination invalid or inactive!\n",
 500                                      t->parms.name);
 501                 rel_msg = 1;
 502                 break;
 503         case ICMPV6_TIME_EXCEED:
 504                 if ((*code) == ICMPV6_EXC_HOPLIMIT) {
 505                         net_warn_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n",
 506                                              t->parms.name);
 507                         rel_msg = 1;
 508                 }
 509                 break;
 510         case ICMPV6_PARAMPROB:
 511                 teli = 0;
 512                 if ((*code) == ICMPV6_HDR_FIELD)
 513                         teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data);
 514
 515                 if (teli && teli == *info - 2) {
 516                         tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli];
 517                         if (tel->encap_limit == 0) {
 518                                 net_warn_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n",
 519                                                      t->parms.name);
 520                                 rel_msg = 1;
 521                         }
 522                 } else {
 523                         net_warn_ratelimited("%s: Recipient unable to parse tunneled packet!\n",
 524                                              t->parms.name);
 525                 }
 526                 break;
 527         case ICMPV6_PKT_TOOBIG:
 528                 mtu = *info - offset;
 529                 if (mtu < IPV6_MIN_MTU)
 530                         mtu = IPV6_MIN_MTU;
 531                 t->dev->mtu = mtu;
 532
 533                 if ((len = sizeof (*ipv6h) + ntohs(ipv6h->payload_len)) > mtu) {
 534                         rel_type = ICMPV6_PKT_TOOBIG;
 535                         rel_code = 0;
 536                         rel_info = mtu;
 537                         rel_msg = 1;
 538                 }
 539                 break;
 540         }
 541
 542         *type = rel_type;
 543         *code = rel_code;
 544         *info = rel_info;
 545         *msg = rel_msg;
 546
 547 out:
 548         rcu_read_unlock();
 549         return err;
 550 }
 551
 552 static int
 553 ip4ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 554            u8 type, u8 code, int offset, __be32 info)
 555 {
 556         int rel_msg = 0;
 557         u8 rel_type = type;
 558         u8 rel_code = code;
 559         __u32 rel_info = ntohl(info);
 560         int err;
 561         struct sk_buff *skb2;
 562         const struct iphdr *eiph;
 563         struct rtable *rt;
 564         struct flowi4 fl4;
 565
 566         err = ip6_tnl_err(skb, IPPROTO_IPIP, opt, &rel_type, &rel_code,
 567                           &rel_msg, &rel_info, offset);
 568         if (err < 0)
 569                 return err;
 570
 571         if (rel_msg == 0)
 572                 return 0;
 573
 574         switch (rel_type) {
 575         case ICMPV6_DEST_UNREACH:
 576                 if (rel_code != ICMPV6_ADDR_UNREACH)
 577                         return 0;
 578                 rel_type = ICMP_DEST_UNREACH;
 579                 rel_code = ICMP_HOST_UNREACH;
 580                 break;
 581         case ICMPV6_PKT_TOOBIG:
 582                 if (rel_code != 0)
 583                         return 0;
 584                 rel_type = ICMP_DEST_UNREACH;
 585                 rel_code = ICMP_FRAG_NEEDED;
 586                 break;
 587         case NDISC_REDIRECT:
 588                 rel_type = ICMP_REDIRECT;
 589                 rel_code = ICMP_REDIR_HOST;
 590         default:
 591                 return 0;
 592         }
 593
 594         if (!pskb_may_pull(skb, offset + sizeof(struct iphdr)))
 595                 return 0;
 596
 597         skb2 = skb_clone(skb, GFP_ATOMIC);
 598         if (!skb2)
 599                 return 0;
 600
 601         skb_dst_drop(skb2);
 602
 603         skb_pull(skb2, offset);
 604         skb_reset_network_header(skb2);
 605         eiph = ip_hdr(skb2);
 606
 607         /* Try to guess incoming interface */
 608         rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL,
 609                                    eiph->saddr, 0,
 610                                    0, 0,
 611                                    IPPROTO_IPIP, RT_TOS(eiph->tos), 0);
 612         if (IS_ERR(rt))
 613                 goto out;
 614
 615         skb2->dev = rt->dst.dev;
 616
 617         /* route "incoming" packet */
 618         if (rt->rt_flags & RTCF_LOCAL) {
 619                 ip_rt_put(rt);
 620                 rt = NULL;
 621                 rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL,
 622                                            eiph->daddr, eiph->saddr,
 623                                            0, 0,
 624                                            IPPROTO_IPIP,
 625                                            RT_TOS(eiph->tos), 0);
 626                 if (IS_ERR(rt) ||
 627                     rt->dst.dev->type != ARPHRD_TUNNEL) {
 628                         if (!IS_ERR(rt))
 629                                 ip_rt_put(rt);
 630                         goto out;
 631                 }
 632                 skb_dst_set(skb2, &rt->dst);
 633         } else {
 634                 ip_rt_put(rt);
 635                 if (ip_route_input(skb2, eiph->daddr, eiph->saddr, eiph->tos,
 636                                    skb2->dev) ||
 637                     skb_dst(skb2)->dev->type != ARPHRD_TUNNEL)
 638                         goto out;
 639         }
 640
 641         /* change mtu on this route */
 642         if (rel_type == ICMP_DEST_UNREACH && rel_code == ICMP_FRAG_NEEDED) {
 643                 if (rel_info > dst_mtu(skb_dst(skb2)))
 644                         goto out;
 645
 646                 skb_dst(skb2)->ops->update_pmtu(skb_dst(skb2), NULL, skb2, rel_info);
 647         }
 648         if (rel_type == ICMP_REDIRECT)
 649                 skb_dst(skb2)->ops->redirect(skb_dst(skb2), NULL, skb2);
 650
 651         icmp_send(skb2, rel_type, rel_code, htonl(rel_info));
 652
 653 out:
 654         kfree_skb(skb2);
 655         return 0;
 656 }
 657
 658 static int
 659 ip6ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 660            u8 type, u8 code, int offset, __be32 info)
 661 {
 662         int rel_msg = 0;
 663         u8 rel_type = type;
 664         u8 rel_code = code;
 665         __u32 rel_info = ntohl(info);
 666         int err;
 667
 668         err = ip6_tnl_err(skb, IPPROTO_IPV6, opt, &rel_type, &rel_code,
 669                           &rel_msg, &rel_info, offset);
 670         if (err < 0)
 671                 return err;
 672
 673         if (rel_msg && pskb_may_pull(skb, offset + sizeof(struct ipv6hdr))) {
 674                 struct rt6_info *rt;
 675                 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
 676
 677                 if (!skb2)
 678                         return 0;
 679
 680                 skb_dst_drop(skb2);
 681                 skb_pull(skb2, offset);
 682                 skb_reset_network_header(skb2);
 683
 684                 /* Try to guess incoming interface */
 685                 rt = rt6_lookup(dev_net(skb->dev), &ipv6_hdr(skb2)->saddr,
 686                                 NULL, 0, 0);
 687
 688                 if (rt && rt->dst.dev)
 689                         skb2->dev = rt->dst.dev;
 690
 691                 icmpv6_send(skb2, rel_type, rel_code, rel_info);
 692
 693                 ip6_rt_put(rt);
 694
 695                 kfree_skb(skb2);
 696         }
 697
 698         return 0;
 699 }
 700
 701 static int ip4ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t,
 702                                        const struct ipv6hdr *ipv6h,
 703                                        struct sk_buff *skb)
 704 {
 705         __u8 dsfield = ipv6_get_dsfield(ipv6h) & ~INET_ECN_MASK;
 706
 707         if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY)
 708                 ipv4_change_dsfield(ip_hdr(skb), INET_ECN_MASK, dsfield);
 709
 710         return IP6_ECN_decapsulate(ipv6h, skb);
 711 }
 712
 713 static int ip6ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t,
 714                                        const struct ipv6hdr *ipv6h,
 715                                        struct sk_buff *skb)
 716 {
 717         if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY)
 718                 ipv6_copy_dscp(ipv6_get_dsfield(ipv6h), ipv6_hdr(skb));
 719
 720         return IP6_ECN_decapsulate(ipv6h, skb);
 721 }
 722
 723 __u32 ip6_tnl_get_cap(struct ip6_tnl *t,
 724                              const struct in6_addr *laddr,
 725                              const struct in6_addr *raddr)
 726 {
 727         struct __ip6_tnl_parm *p = &t->parms;
 728         int ltype = ipv6_addr_type(laddr);
 729         int rtype = ipv6_addr_type(raddr);
 730         __u32 flags = 0;
 731
 732         if (ltype == IPV6_ADDR_ANY || rtype == IPV6_ADDR_ANY) {
 733                 flags = IP6_TNL_F_CAP_PER_PACKET;
 734         } else if (ltype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) &&
 735                    rtype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) &&
 736                    !((ltype|rtype) & IPV6_ADDR_LOOPBACK) &&
 737                    (!((ltype|rtype) & IPV6_ADDR_LINKLOCAL) || p->link)) {
 738                 if (ltype&IPV6_ADDR_UNICAST)
 739                         flags |= IP6_TNL_F_CAP_XMIT;
 740                 if (rtype&IPV6_ADDR_UNICAST)
 741                         flags |= IP6_TNL_F_CAP_RCV;
 742         }
 743         return flags;
 744 }
 745 EXPORT_SYMBOL(ip6_tnl_get_cap);
 746
 747 /* called with rcu_read_lock() */
 748 int ip6_tnl_rcv_ctl(struct ip6_tnl *t,
 749                                   const struct in6_addr *laddr,
 750                                   const struct in6_addr *raddr)
 751 {
 752         struct __ip6_tnl_parm *p = &t->parms;
 753         int ret = 0;
 754         struct net *net = t->net;
 755
 756         if ((p->flags & IP6_TNL_F_CAP_RCV) ||
 757             ((p->flags & IP6_TNL_F_CAP_PER_PACKET) &&
 758              (ip6_tnl_get_cap(t, laddr, raddr) & IP6_TNL_F_CAP_RCV))) {
 759                 struct net_device *ldev = NULL;
 760
 761                 if (p->link)
 762                         ldev = dev_get_by_index_rcu(net, p->link);
 763
 764                 if ((ipv6_addr_is_multicast(laddr) ||
 765                      likely(ipv6_chk_addr(net, laddr, ldev, 0))) &&
 766                     likely(!ipv6_chk_addr(net, raddr, NULL, 0)))
 767                         ret = 1;
 768         }
 769         return ret;
 770 }
 771 EXPORT_SYMBOL_GPL(ip6_tnl_rcv_ctl);
 772
 773 /**
 774  * ip6_tnl_rcv - decapsulate IPv6 packet and retransmit it locally
 775  *   @skb: received socket buffer
 776  *   @protocol: ethernet protocol ID
 777  *   @dscp_ecn_decapsulate: the function to decapsulate DSCP code and ECN
 778  *
 779  * Return: 0
 780  **/
 781
 782 static int ip6_tnl_rcv(struct sk_buff *skb, __u16 protocol,
 783                        __u8 ipproto,
 784                        int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t,
 785                                                    const struct ipv6hdr *ipv6h,
 786                                                    struct sk_buff *skb))
 787 {
 788         struct ip6_tnl *t;
 789         const struct ipv6hdr *ipv6h = ipv6_hdr(skb);
 790         int err;
 791
 792         rcu_read_lock();
 793
 794         if ((t = ip6_tnl_lookup(dev_net(skb->dev), &ipv6h->saddr,
 795                                         &ipv6h->daddr)) != NULL) {
 796                 struct pcpu_sw_netstats *tstats;
 797
 798                 if (t->parms.proto != ipproto && t->parms.proto != 0) {
 799                         rcu_read_unlock();
 800                         goto discard;
 801                 }
 802
 803                 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) {
 804                         rcu_read_unlock();
 805                         goto discard;
 806                 }
 807
 808                 if (!ip6_tnl_rcv_ctl(t, &ipv6h->daddr, &ipv6h->saddr)) {
 809                         t->dev->stats.rx_dropped++;
 810                         rcu_read_unlock();
 811                         goto discard;
 812                 }
 813                 skb->mac_header = skb->network_header;
 814                 skb_reset_network_header(skb);
 815                 skb->protocol = htons(protocol);
 816                 memset(skb->cb, 0, sizeof(struct inet6_skb_parm));
 817
 818                 __skb_tunnel_rx(skb, t->dev, t->net);
 819
 820                 err = dscp_ecn_decapsulate(t, ipv6h, skb);
 821                 if (unlikely(err)) {
 822                         if (log_ecn_error)
 823                                 net_info_ratelimited("non-ECT from %pI6 with dsfield=%#x\n",
 824                                                      &ipv6h->saddr,
 825                                                      ipv6_get_dsfield(ipv6h));
 826                         if (err > 1) {
 827                                 ++t->dev->stats.rx_frame_errors;
 828                                 ++t->dev->stats.rx_errors;
 829                                 rcu_read_unlock();
 830                                 goto discard;
 831                         }
 832                 }
 833
 834                 tstats = this_cpu_ptr(t->dev->tstats);
 835                 u64_stats_update_begin(&tstats->syncp);
 836                 tstats->rx_packets++;
 837                 tstats->rx_bytes += skb->len;
 838                 u64_stats_update_end(&tstats->syncp);
 839
 840                 netif_rx(skb);
 841
 842                 rcu_read_unlock();
 843                 return 0;
 844         }
 845         rcu_read_unlock();
 846         return 1;
 847
 848 discard:
 849         kfree_skb(skb);
 850         return 0;
 851 }
 852
 853 static int ip4ip6_rcv(struct sk_buff *skb)
 854 {
 855         return ip6_tnl_rcv(skb, ETH_P_IP, IPPROTO_IPIP,
 856                            ip4ip6_dscp_ecn_decapsulate);
 857 }
 858
 859 static int ip6ip6_rcv(struct sk_buff *skb)
 860 {
 861         return ip6_tnl_rcv(skb, ETH_P_IPV6, IPPROTO_IPV6,
 862                            ip6ip6_dscp_ecn_decapsulate);
 863 }
 864
 865 struct ipv6_tel_txoption {
 866         struct ipv6_txoptions ops;
 867         __u8 dst_opt[8];
 868 };
 869
 870 static void init_tel_txopt(struct ipv6_tel_txoption *opt, __u8 encap_limit)
 871 {
 872         memset(opt, 0, sizeof(struct ipv6_tel_txoption));
 873
 874         opt->dst_opt[2] = IPV6_TLV_TNL_ENCAP_LIMIT;
 875         opt->dst_opt[3] = 1;
 876         opt->dst_opt[4] = encap_limit;
 877         opt->dst_opt[5] = IPV6_TLV_PADN;
 878         opt->dst_opt[6] = 1;
 879
 880         opt->ops.dst0opt = (struct ipv6_opt_hdr *) opt->dst_opt;
 881         opt->ops.opt_nflen = 8;
 882 }
 883
 884 /**
 885  * ip6_tnl_addr_conflict - compare packet addresses to tunnel's own
 886  *   @t: the outgoing tunnel device
 887  *   @hdr: IPv6 header from the incoming packet
 888  *
 889  * Description:
 890  *   Avoid trivial tunneling loop by checking that tunnel exit-point
 891  *   doesn't match source of incoming packet.
 892  *
 893  * Return:
 894  *   1 if conflict,
 895  *   0 else
 896  **/
 897
 898 static inline bool
 899 ip6_tnl_addr_conflict(const struct ip6_tnl *t, const struct ipv6hdr *hdr)
 900 {
 901         return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr);
 902 }
 903
 904 int ip6_tnl_xmit_ctl(struct ip6_tnl *t)
 905 {
 906         struct __ip6_tnl_parm *p = &t->parms;
 907         int ret = 0;
 908         struct net *net = t->net;
 909
 910         if (p->flags & IP6_TNL_F_CAP_XMIT) {
 911                 struct net_device *ldev = NULL;
 912
 913                 rcu_read_lock();
 914                 if (p->link)
 915                         ldev = dev_get_by_index_rcu(net, p->link);
 916
 917                 if (unlikely(!ipv6_chk_addr(net, &p->laddr, ldev, 0)))
 918                         pr_warn("%s xmit: Local address not yet configured!\n",
 919                                 p->name);
 920                 else if (!ipv6_addr_is_multicast(&p->raddr) &&
 921                          unlikely(ipv6_chk_addr(net, &p->raddr, NULL, 0)))
 922                         pr_warn("%s xmit: Routing loop! Remote address found on this node!\n",
 923                                 p->name);
 924                 else
 925                         ret = 1;
 926                 rcu_read_unlock();
 927         }
 928         return ret;
 929 }
 930 EXPORT_SYMBOL_GPL(ip6_tnl_xmit_ctl);
 931
 932 /**
 933  * ip6_tnl_xmit2 - encapsulate packet and send
 934  *   @skb: the outgoing socket buffer
 935  *   @dev: the outgoing tunnel device
 936  *   @dsfield: dscp code for outer header
 937  *   @fl: flow of tunneled packet
 938  *   @encap_limit: encapsulation limit
 939  *   @pmtu: Path MTU is stored if packet is too big
 940  *
 941  * Description:
 942  *   Build new header and do some sanity checks on the packet before sending
 943  *   it.
 944  *
 945  * Return:
 946  *   0 on success
 947  *   -1 fail
 948  *   %-EMSGSIZE message too big. return mtu in this case.
 949  **/
 950
 951 static int ip6_tnl_xmit2(struct sk_buff *skb,
 952                          struct net_device *dev,
 953                          __u8 dsfield,
 954                          struct flowi6 *fl6,
 955                          int encap_limit,
 956                          __u32 *pmtu)
 957 {
 958         struct ip6_tnl *t = netdev_priv(dev);
 959         struct net *net = t->net;
 960         struct net_device_stats *stats = &t->dev->stats;
 961         struct ipv6hdr *ipv6h = ipv6_hdr(skb);
 962         struct ipv6_tel_txoption opt;
 963         struct dst_entry *dst = NULL, *ndst = NULL;
 964         struct net_device *tdev;
 965         int mtu;
 966         unsigned int max_headroom = sizeof(struct ipv6hdr);
 967         u8 proto;
 968         int err = -1;
 969
 970         if (!fl6->flowi6_mark)
 971                 dst = ip6_tnl_dst_check(t);
 972         if (!dst) {
 973                 ndst = ip6_route_output(net, NULL, fl6);
 974
 975                 if (ndst->error)
 976                         goto tx_err_link_failure;
 977                 ndst = xfrm_lookup(net, ndst, flowi6_to_flowi(fl6), NULL, 0);
 978                 if (IS_ERR(ndst)) {
 979                         err = PTR_ERR(ndst);
 980                         ndst = NULL;
 981                         goto tx_err_link_failure;
 982                 }
 983                 dst = ndst;
 984         }
 985
 986         tdev = dst->dev;
 987
 988         if (tdev == dev) {
 989                 stats->collisions++;
 990                 net_warn_ratelimited("%s: Local routing loop detected!\n",
 991                                      t->parms.name);
 992                 goto tx_err_dst_release;
 993         }
 994         mtu = dst_mtu(dst) - sizeof (*ipv6h);
 995         if (encap_limit >= 0) {
 996                 max_headroom += 8;
 997                 mtu -= 8;
 998         }
 999         if (mtu < IPV6_MIN_MTU)
1000                 mtu = IPV6_MIN_MTU;
1001         if (skb_dst(skb))
1002                 skb_dst(skb)->ops->update_pmtu(skb_dst(skb), NULL, skb, mtu);
1003         if (skb->len > mtu) {
1004                 *pmtu = mtu;
1005                 err = -EMSGSIZE;
1006                 goto tx_err_dst_release;
1007         }
1008
1009         skb_scrub_packet(skb, !net_eq(t->net, dev_net(dev)));
1010
1011         /*
1012          * Okay, now see if we can stuff it in the buffer as-is.
1013          */
1014         max_headroom += LL_RESERVED_SPACE(tdev);
1015
1016         if (skb_headroom(skb) < max_headroom || skb_shared(skb) ||
1017             (skb_cloned(skb) && !skb_clone_writable(skb, 0))) {
1018                 struct sk_buff *new_skb;
1019
1020                 if (!(new_skb = skb_realloc_headroom(skb, max_headroom)))
1021                         goto tx_err_dst_release;
1022
1023                 if (skb->sk)
1024                         skb_set_owner_w(new_skb, skb->sk);
1025                 consume_skb(skb);
1026                 skb = new_skb;
1027         }
1028         if (fl6->flowi6_mark) {
1029                 skb_dst_set(skb, dst);
1030                 ndst = NULL;
1031         } else {
1032                 skb_dst_set_noref(skb, dst);
1033         }
1034         skb->transport_header = skb->network_header;
1035
1036         proto = fl6->flowi6_proto;
1037         if (encap_limit >= 0) {
1038                 init_tel_txopt(&opt, encap_limit);
1039                 ipv6_push_nfrag_opts(skb, &opt.ops, &proto, NULL);
1040         }
1041
1042         if (likely(!skb->encapsulation)) {
1043                 skb_reset_inner_headers(skb);
1044                 skb->encapsulation = 1;
1045         }
1046
1047         skb_push(skb, sizeof(struct ipv6hdr));
1048         skb_reset_network_header(skb);
1049         ipv6h = ipv6_hdr(skb);
1050         ip6_flow_hdr(ipv6h, INET_ECN_encapsulate(0, dsfield), fl6->flowlabel);
1051         ipv6h->hop_limit = t->parms.hop_limit;
1052         ipv6h->nexthdr = proto;
1053         ipv6h->saddr = fl6->saddr;
1054         ipv6h->daddr = fl6->daddr;
1055         ip6tunnel_xmit(skb, dev);
1056         if (ndst)
1057                 ip6_tnl_dst_store(t, ndst);
1058         return 0;
1059 tx_err_link_failure:
1060         stats->tx_carrier_errors++;
1061         dst_link_failure(skb);
1062 tx_err_dst_release:
1063         dst_release(ndst);
1064         return err;
1065 }
1066
1067 static inline int
1068 ip4ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev)
1069 {
1070         struct ip6_tnl *t = netdev_priv(dev);
1071         const struct iphdr  *iph = ip_hdr(skb);
1072         int encap_limit = -1;
1073         struct flowi6 fl6;
1074         __u8 dsfield;
1075         __u32 mtu;
1076         int err;
1077
1078         if ((t->parms.proto != IPPROTO_IPIP && t->parms.proto != 0) ||
1079             !ip6_tnl_xmit_ctl(t))
1080                 return -1;
1081
1082         if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1083                 encap_limit = t->parms.encap_limit;
1084
1085         memcpy(&fl6, &t->fl.u.ip6, sizeof (fl6));
1086         fl6.flowi6_proto = IPPROTO_IPIP;
1087
1088         dsfield = ipv4_get_dsfield(iph);
1089
1090         if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
1091                 fl6.flowlabel |= htonl((__u32)iph->tos << IPV6_TCLASS_SHIFT)
1092                                           & IPV6_TCLASS_MASK;
1093         if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
1094                 fl6.flowi6_mark = skb->mark;
1095
1096         err = ip6_tnl_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu);
1097         if (err != 0) {
1098                 /* XXX: send ICMP error even if DF is not set. */
1099                 if (err == -EMSGSIZE)
1100                         icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
1101                                   htonl(mtu));
1102                 return -1;
1103         }
1104
1105         return 0;
1106 }
1107
1108 static inline int
1109 ip6ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev)
1110 {
1111         struct ip6_tnl *t = netdev_priv(dev);
1112         struct ipv6hdr *ipv6h = ipv6_hdr(skb);
1113         int encap_limit = -1;
1114         __u16 offset;
1115         struct flowi6 fl6;
1116         __u8 dsfield;
1117         __u32 mtu;
1118         int err;
1119
1120         if ((t->parms.proto != IPPROTO_IPV6 && t->parms.proto != 0) ||
1121             !ip6_tnl_xmit_ctl(t) || ip6_tnl_addr_conflict(t, ipv6h))
1122                 return -1;
1123
1124         offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb));
1125         if (offset > 0) {
1126                 struct ipv6_tlv_tnl_enc_lim *tel;
1127                 tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset];
1128                 if (tel->encap_limit == 0) {
1129                         icmpv6_send(skb, ICMPV6_PARAMPROB,
1130                                     ICMPV6_HDR_FIELD, offset + 2);
1131                         return -1;
1132                 }
1133                 encap_limit = tel->encap_limit - 1;
1134         } else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1135                 encap_limit = t->parms.encap_limit;
1136
1137         memcpy(&fl6, &t->fl.u.ip6, sizeof (fl6));
1138         fl6.flowi6_proto = IPPROTO_IPV6;
1139
1140         dsfield = ipv6_get_dsfield(ipv6h);
1141         if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
1142                 fl6.flowlabel |= (*(__be32 *) ipv6h & IPV6_TCLASS_MASK);
1143         if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL)
1144                 fl6.flowlabel |= ip6_flowlabel(ipv6h);
1145         if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
1146                 fl6.flowi6_mark = skb->mark;
1147
1148         err = ip6_tnl_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu);
1149         if (err != 0) {
1150                 if (err == -EMSGSIZE)
1151                         icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
1152                 return -1;
1153         }
1154
1155         return 0;
1156 }
1157
1158 static netdev_tx_t
1159 ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev)
1160 {
1161         struct ip6_tnl *t = netdev_priv(dev);
1162         struct net_device_stats *stats = &t->dev->stats;
1163         int ret;
1164
1165         switch (skb->protocol) {
1166         case htons(ETH_P_IP):
1167                 ret = ip4ip6_tnl_xmit(skb, dev);
1168                 break;
1169         case htons(ETH_P_IPV6):
1170                 ret = ip6ip6_tnl_xmit(skb, dev);
1171                 break;
1172         default:
1173                 goto tx_err;
1174         }
1175
1176         if (ret < 0)
1177                 goto tx_err;
1178
1179         return NETDEV_TX_OK;
1180
1181 tx_err:
1182         stats->tx_errors++;
1183         stats->tx_dropped++;
1184         kfree_skb(skb);
1185         return NETDEV_TX_OK;
1186 }
1187
1188 static void ip6_tnl_link_config(struct ip6_tnl *t)
1189 {
1190         struct net_device *dev = t->dev;
1191         struct __ip6_tnl_parm *p = &t->parms;
1192         struct flowi6 *fl6 = &t->fl.u.ip6;
1193
1194         memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr));
1195         memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr));
1196
1197         /* Set up flowi template */
1198         fl6->saddr = p->laddr;
1199         fl6->daddr = p->raddr;
1200         fl6->flowi6_oif = p->link;
1201         fl6->flowlabel = 0;
1202
1203         if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS))
1204                 fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo;
1205         if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL))
1206                 fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo;
1207
1208         p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET);
1209         p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr);
1210
1211         if (p->flags&IP6_TNL_F_CAP_XMIT && p->flags&IP6_TNL_F_CAP_RCV)
1212                 dev->flags |= IFF_POINTOPOINT;
1213         else
1214                 dev->flags &= ~IFF_POINTOPOINT;
1215
1216         dev->iflink = p->link;
1217
1218         if (p->flags & IP6_TNL_F_CAP_XMIT) {
1219                 int strict = (ipv6_addr_type(&p->raddr) &
1220                               (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL));
1221
1222                 struct rt6_info *rt = rt6_lookup(t->net,
1223                                                  &p->raddr, &p->laddr,
1224                                                  p->link, strict);
1225
1226                 if (rt == NULL)
1227                         return;
1228
1229                 if (rt->dst.dev) {
1230                         dev->hard_header_len = rt->dst.dev->hard_header_len +
1231                                 sizeof (struct ipv6hdr);
1232
1233                         dev->mtu = rt->dst.dev->mtu - sizeof (struct ipv6hdr);
1234                         if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1235                                 dev->mtu-=8;
1236
1237                         if (dev->mtu < IPV6_MIN_MTU)
1238                                 dev->mtu = IPV6_MIN_MTU;
1239                 }
1240                 ip6_rt_put(rt);
1241         }
1242 }
1243
1244 /**
1245  * ip6_tnl_change - update the tunnel parameters
1246  *   @t: tunnel to be changed
1247  *   @p: tunnel configuration parameters
1248  *
1249  * Description:
1250  *   ip6_tnl_change() updates the tunnel parameters
1251  **/
1252
1253 static int
1254 ip6_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p)
1255 {
1256         t->parms.laddr = p->laddr;
1257         t->parms.raddr = p->raddr;
1258         t->parms.flags = p->flags;
1259         t->parms.hop_limit = p->hop_limit;
1260         t->parms.encap_limit = p->encap_limit;
1261         t->parms.flowinfo = p->flowinfo;
1262         t->parms.link = p->link;
1263         t->parms.proto = p->proto;
1264         ip6_tnl_dst_reset(t);
1265         ip6_tnl_link_config(t);
1266         return 0;
1267 }
1268
1269 static int ip6_tnl_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p)
1270 {
1271         struct net *net = t->net;
1272         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1273         int err;
1274
1275         ip6_tnl_unlink(ip6n, t);
1276         synchronize_net();
1277         err = ip6_tnl_change(t, p);
1278         ip6_tnl_link(ip6n, t);
1279         netdev_state_change(t->dev);
1280         return err;
1281 }
1282
1283 static void
1284 ip6_tnl_parm_from_user(struct __ip6_tnl_parm *p, const struct ip6_tnl_parm *u)
1285 {
1286         p->laddr = u->laddr;
1287         p->raddr = u->raddr;
1288         p->flags = u->flags;
1289         p->hop_limit = u->hop_limit;
1290         p->encap_limit = u->encap_limit;
1291         p->flowinfo = u->flowinfo;
1292         p->link = u->link;
1293         p->proto = u->proto;
1294         memcpy(p->name, u->name, sizeof(u->name));
1295 }
1296
1297 static void
1298 ip6_tnl_parm_to_user(struct ip6_tnl_parm *u, const struct __ip6_tnl_parm *p)
1299 {
1300         u->laddr = p->laddr;
1301         u->raddr = p->raddr;
1302         u->flags = p->flags;
1303         u->hop_limit = p->hop_limit;
1304         u->encap_limit = p->encap_limit;
1305         u->flowinfo = p->flowinfo;
1306         u->link = p->link;
1307         u->proto = p->proto;
1308         memcpy(u->name, p->name, sizeof(u->name));
1309 }
1310
1311 /**
1312  * ip6_tnl_ioctl - configure ipv6 tunnels from userspace
1313  *   @dev: virtual device associated with tunnel
1314  *   @ifr: parameters passed from userspace
1315  *   @cmd: command to be performed
1316  *
1317  * Description:
1318  *   ip6_tnl_ioctl() is used for managing IPv6 tunnels
1319  *   from userspace.
1320  *
1321  *   The possible commands are the following:
1322  *     %SIOCGETTUNNEL: get tunnel parameters for device
1323  *     %SIOCADDTUNNEL: add tunnel matching given tunnel parameters
1324  *     %SIOCCHGTUNNEL: change tunnel parameters to those given
1325  *     %SIOCDELTUNNEL: delete tunnel
1326  *
1327  *   The fallback device "ip6tnl0", created during module
1328  *   initialization, can be used for creating other tunnel devices.
1329  *
1330  * Return:
1331  *   0 on success,
1332  *   %-EFAULT if unable to copy data to or from userspace,
1333  *   %-EPERM if current process hasn't %CAP_NET_ADMIN set
1334  *   %-EINVAL if passed tunnel parameters are invalid,
1335  *   %-EEXIST if changing a tunnel's parameters would cause a conflict
1336  *   %-ENODEV if attempting to change or delete a nonexisting device
1337  **/
1338
1339 static int
1340 ip6_tnl_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
1341 {
1342         int err = 0;
1343         struct ip6_tnl_parm p;
1344         struct __ip6_tnl_parm p1;
1345         struct ip6_tnl *t = NULL;
1346         struct net *net = dev_net(dev);
1347         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1348
1349         switch (cmd) {
1350         case SIOCGETTUNNEL:
1351                 if (dev == ip6n->fb_tnl_dev) {
1352                         if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p))) {
1353                                 err = -EFAULT;
1354                                 break;
1355                         }
1356                         ip6_tnl_parm_from_user(&p1, &p);
1357                         t = ip6_tnl_locate(net, &p1, 0);
1358                 } else {
1359                         memset(&p, 0, sizeof(p));
1360                 }
1361                 if (t == NULL)
1362                         t = netdev_priv(dev);
1363                 ip6_tnl_parm_to_user(&p, &t->parms);
1364                 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof (p))) {
1365                         err = -EFAULT;
1366                 }
1367                 break;
1368         case SIOCADDTUNNEL:
1369         case SIOCCHGTUNNEL:
1370                 err = -EPERM;
1371                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1372                         break;
1373                 err = -EFAULT;
1374                 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p)))
1375                         break;
1376                 err = -EINVAL;
1377                 if (p.proto != IPPROTO_IPV6 && p.proto != IPPROTO_IPIP &&
1378                     p.proto != 0)
1379                         break;
1380                 ip6_tnl_parm_from_user(&p1, &p);
1381                 t = ip6_tnl_locate(net, &p1, cmd == SIOCADDTUNNEL);
1382                 if (dev != ip6n->fb_tnl_dev && cmd == SIOCCHGTUNNEL) {
1383                         if (t != NULL) {
1384                                 if (t->dev != dev) {
1385                                         err = -EEXIST;
1386                                         break;
1387                                 }
1388                         } else
1389                                 t = netdev_priv(dev);
1390
1391                         err = ip6_tnl_update(t, &p1);
1392                 }
1393                 if (t) {
1394                         err = 0;
1395                         ip6_tnl_parm_to_user(&p, &t->parms);
1396                         if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
1397                                 err = -EFAULT;
1398
1399                 } else
1400                         err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
1401                 break;
1402         case SIOCDELTUNNEL:
1403                 err = -EPERM;
1404                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1405                         break;
1406
1407                 if (dev == ip6n->fb_tnl_dev) {
1408                         err = -EFAULT;
1409                         if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p)))
1410                                 break;
1411                         err = -ENOENT;
1412                         ip6_tnl_parm_from_user(&p1, &p);
1413                         t = ip6_tnl_locate(net, &p1, 0);
1414                         if (t == NULL)
1415                                 break;
1416                         err = -EPERM;
1417                         if (t->dev == ip6n->fb_tnl_dev)
1418                                 break;
1419                         dev = t->dev;
1420                 }
1421                 err = 0;
1422                 unregister_netdevice(dev);
1423                 break;
1424         default:
1425                 err = -EINVAL;
1426         }
1427         return err;
1428 }
1429
1430 /**
1431  * ip6_tnl_change_mtu - change mtu manually for tunnel device
1432  *   @dev: virtual device associated with tunnel
1433  *   @new_mtu: the new mtu
1434  *
1435  * Return:
1436  *   0 on success,
1437  *   %-EINVAL if mtu too small
1438  **/
1439
1440 static int
1441 ip6_tnl_change_mtu(struct net_device *dev, int new_mtu)
1442 {
1443         struct ip6_tnl *tnl = netdev_priv(dev);
1444
1445         if (tnl->parms.proto == IPPROTO_IPIP) {
1446                 if (new_mtu < 68)
1447                         return -EINVAL;
1448         } else {
1449                 if (new_mtu < IPV6_MIN_MTU)
1450                         return -EINVAL;
1451         }
1452         if (new_mtu > 0xFFF8 - dev->hard_header_len)
1453                 return -EINVAL;
1454         dev->mtu = new_mtu;
1455         return 0;
1456 }
1457
1458
1459 static const struct net_device_ops ip6_tnl_netdev_ops = {
1460         .ndo_uninit     = ip6_tnl_dev_uninit,
1461         .ndo_start_xmit = ip6_tnl_xmit,
1462         .ndo_do_ioctl   = ip6_tnl_ioctl,
1463         .ndo_change_mtu = ip6_tnl_change_mtu,
1464         .ndo_get_stats  = ip6_get_stats,
1465 };
1466
1467
1468 /**
1469  * ip6_tnl_dev_setup - setup virtual tunnel device
1470  *   @dev: virtual device associated with tunnel
1471  *
1472  * Description:
1473  *   Initialize function pointers and device parameters
1474  **/
1475
1476 static void ip6_tnl_dev_setup(struct net_device *dev)
1477 {
1478         struct ip6_tnl *t;
1479
1480         dev->netdev_ops = &ip6_tnl_netdev_ops;
1481         dev->destructor = ip6_dev_free;
1482
1483         dev->type = ARPHRD_TUNNEL6;
1484         dev->hard_header_len = LL_MAX_HEADER + sizeof (struct ipv6hdr);
1485         dev->mtu = ETH_DATA_LEN - sizeof (struct ipv6hdr);
1486         t = netdev_priv(dev);
1487         if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1488                 dev->mtu-=8;
1489         dev->flags |= IFF_NOARP;
1490         dev->addr_len = sizeof(struct in6_addr);
1491         dev->priv_flags &= ~IFF_XMIT_DST_RELEASE;
1492         /* This perm addr will be used as interface identifier by IPv6 */
1493         dev->addr_assign_type = NET_ADDR_RANDOM;
1494         eth_random_addr(dev->perm_addr);
1495 }
1496
1497
1498 /**
1499  * ip6_tnl_dev_init_gen - general initializer for all tunnel devices
1500  *   @dev: virtual device associated with tunnel
1501  **/
1502
1503 static inline int
1504 ip6_tnl_dev_init_gen(struct net_device *dev)
1505 {
1506         struct ip6_tnl *t = netdev_priv(dev);
1507         int i;
1508
1509         t->dev = dev;
1510         t->net = dev_net(dev);
1511         dev->tstats = alloc_percpu(struct pcpu_sw_netstats);
1512         if (!dev->tstats)
1513                 return -ENOMEM;
1514
1515         for_each_possible_cpu(i) {
1516                 struct pcpu_sw_netstats *ip6_tnl_stats;
1517                 ip6_tnl_stats = per_cpu_ptr(dev->tstats, i);
1518                 u64_stats_init(&ip6_tnl_stats->syncp);
1519         }
1520         return 0;
1521 }
1522
1523 /**
1524  * ip6_tnl_dev_init - initializer for all non fallback tunnel devices
1525  *   @dev: virtual device associated with tunnel
1526  **/
1527
1528 static int ip6_tnl_dev_init(struct net_device *dev)
1529 {
1530         struct ip6_tnl *t = netdev_priv(dev);
1531         int err = ip6_tnl_dev_init_gen(dev);
1532
1533         if (err)
1534                 return err;
1535         ip6_tnl_link_config(t);
1536         return 0;
1537 }
1538
1539 /**
1540  * ip6_fb_tnl_dev_init - initializer for fallback tunnel device
1541  *   @dev: fallback device
1542  *
1543  * Return: 0
1544  **/
1545
1546 static int __net_init ip6_fb_tnl_dev_init(struct net_device *dev)
1547 {
1548         struct ip6_tnl *t = netdev_priv(dev);
1549         struct net *net = dev_net(dev);
1550         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1551         int err = ip6_tnl_dev_init_gen(dev);
1552
1553         if (err)
1554                 return err;
1555
1556         t->parms.proto = IPPROTO_IPV6;
1557         dev_hold(dev);
1558
1559         ip6_tnl_link_config(t);
1560
1561         rcu_assign_pointer(ip6n->tnls_wc[0], t);
1562         return 0;
1563 }
1564
1565 static int ip6_tnl_validate(struct nlattr *tb[], struct nlattr *data[])
1566 {
1567         u8 proto;
1568
1569         if (!data)
1570                 return 0;
1571
1572         proto = nla_get_u8(data[IFLA_IPTUN_PROTO]);
1573         if (proto != IPPROTO_IPV6 &&
1574             proto != IPPROTO_IPIP &&
1575             proto != 0)
1576                 return -EINVAL;
1577
1578         return 0;
1579 }
1580
1581 static void ip6_tnl_netlink_parms(struct nlattr *data[],
1582                                   struct __ip6_tnl_parm *parms)
1583 {
1584         memset(parms, 0, sizeof(*parms));
1585
1586         if (!data)
1587                 return;
1588
1589         if (data[IFLA_IPTUN_LINK])
1590                 parms->link = nla_get_u32(data[IFLA_IPTUN_LINK]);
1591
1592         if (data[IFLA_IPTUN_LOCAL])
1593                 nla_memcpy(&parms->laddr, data[IFLA_IPTUN_LOCAL],
1594                            sizeof(struct in6_addr));
1595
1596         if (data[IFLA_IPTUN_REMOTE])
1597                 nla_memcpy(&parms->raddr, data[IFLA_IPTUN_REMOTE],
1598                            sizeof(struct in6_addr));
1599
1600         if (data[IFLA_IPTUN_TTL])
1601                 parms->hop_limit = nla_get_u8(data[IFLA_IPTUN_TTL]);
1602
1603         if (data[IFLA_IPTUN_ENCAP_LIMIT])
1604                 parms->encap_limit = nla_get_u8(data[IFLA_IPTUN_ENCAP_LIMIT]);
1605
1606         if (data[IFLA_IPTUN_FLOWINFO])
1607                 parms->flowinfo = nla_get_be32(data[IFLA_IPTUN_FLOWINFO]);
1608
1609         if (data[IFLA_IPTUN_FLAGS])
1610                 parms->flags = nla_get_u32(data[IFLA_IPTUN_FLAGS]);
1611
1612         if (data[IFLA_IPTUN_PROTO])
1613                 parms->proto = nla_get_u8(data[IFLA_IPTUN_PROTO]);
1614 }
1615
1616 static int ip6_tnl_newlink(struct net *src_net, struct net_device *dev,
1617                            struct nlattr *tb[], struct nlattr *data[])
1618 {
1619         struct net *net = dev_net(dev);
1620         struct ip6_tnl *nt;
1621
1622         nt = netdev_priv(dev);
1623         ip6_tnl_netlink_parms(data, &nt->parms);
1624
1625         if (ip6_tnl_locate(net, &nt->parms, 0))
1626                 return -EEXIST;
1627
1628         return ip6_tnl_create2(dev);
1629 }
1630
1631 static int ip6_tnl_changelink(struct net_device *dev, struct nlattr *tb[],
1632                               struct nlattr *data[])
1633 {
1634         struct ip6_tnl *t = netdev_priv(dev);
1635         struct __ip6_tnl_parm p;
1636         struct net *net = t->net;
1637         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1638
1639         if (dev == ip6n->fb_tnl_dev)
1640                 return -EINVAL;
1641
1642         ip6_tnl_netlink_parms(data, &p);
1643
1644         t = ip6_tnl_locate(net, &p, 0);
1645
1646         if (t) {
1647                 if (t->dev != dev)
1648                         return -EEXIST;
1649         } else
1650                 t = netdev_priv(dev);
1651
1652         return ip6_tnl_update(t, &p);
1653 }
1654
1655 static void ip6_tnl_dellink(struct net_device *dev, struct list_head *head)
1656 {
1657         struct net *net = dev_net(dev);
1658         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1659
1660         if (dev != ip6n->fb_tnl_dev)
1661                 unregister_netdevice_queue(dev, head);
1662 }
1663
1664 static size_t ip6_tnl_get_size(const struct net_device *dev)
1665 {
1666         return
1667                 /* IFLA_IPTUN_LINK */
1668                 nla_total_size(4) +
1669                 /* IFLA_IPTUN_LOCAL */
1670                 nla_total_size(sizeof(struct in6_addr)) +
1671                 /* IFLA_IPTUN_REMOTE */
1672                 nla_total_size(sizeof(struct in6_addr)) +
1673                 /* IFLA_IPTUN_TTL */
1674                 nla_total_size(1) +
1675                 /* IFLA_IPTUN_ENCAP_LIMIT */
1676                 nla_total_size(1) +
1677                 /* IFLA_IPTUN_FLOWINFO */
1678                 nla_total_size(4) +
1679                 /* IFLA_IPTUN_FLAGS */
1680                 nla_total_size(4) +
1681                 /* IFLA_IPTUN_PROTO */
1682                 nla_total_size(1) +
1683                 0;
1684 }
1685
1686 static int ip6_tnl_fill_info(struct sk_buff *skb, const struct net_device *dev)
1687 {
1688         struct ip6_tnl *tunnel = netdev_priv(dev);
1689         struct __ip6_tnl_parm *parm = &tunnel->parms;
1690
1691         if (nla_put_u32(skb, IFLA_IPTUN_LINK, parm->link) ||
1692             nla_put(skb, IFLA_IPTUN_LOCAL, sizeof(struct in6_addr),
1693                     &parm->laddr) ||
1694             nla_put(skb, IFLA_IPTUN_REMOTE, sizeof(struct in6_addr),
1695                     &parm->raddr) ||
1696             nla_put_u8(skb, IFLA_IPTUN_TTL, parm->hop_limit) ||
1697             nla_put_u8(skb, IFLA_IPTUN_ENCAP_LIMIT, parm->encap_limit) ||
1698             nla_put_be32(skb, IFLA_IPTUN_FLOWINFO, parm->flowinfo) ||
1699             nla_put_u32(skb, IFLA_IPTUN_FLAGS, parm->flags) ||
1700             nla_put_u8(skb, IFLA_IPTUN_PROTO, parm->proto))
1701                 goto nla_put_failure;
1702         return 0;
1703
1704 nla_put_failure:
1705         return -EMSGSIZE;
1706 }
1707
1708 static const struct nla_policy ip6_tnl_policy[IFLA_IPTUN_MAX + 1] = {
1709         [IFLA_IPTUN_LINK]               = { .type = NLA_U32 },
1710         [IFLA_IPTUN_LOCAL]              = { .len = sizeof(struct in6_addr) },
1711         [IFLA_IPTUN_REMOTE]             = { .len = sizeof(struct in6_addr) },
1712         [IFLA_IPTUN_TTL]                = { .type = NLA_U8 },
1713         [IFLA_IPTUN_ENCAP_LIMIT]        = { .type = NLA_U8 },
1714         [IFLA_IPTUN_FLOWINFO]           = { .type = NLA_U32 },
1715         [IFLA_IPTUN_FLAGS]              = { .type = NLA_U32 },
1716         [IFLA_IPTUN_PROTO]              = { .type = NLA_U8 },
1717 };
1718
1719 static struct rtnl_link_ops ip6_link_ops __read_mostly = {
1720         .kind           = "ip6tnl",
1721         .maxtype        = IFLA_IPTUN_MAX,
1722         .policy         = ip6_tnl_policy,
1723         .priv_size      = sizeof(struct ip6_tnl),
1724         .setup          = ip6_tnl_dev_setup,
1725         .validate       = ip6_tnl_validate,
1726         .newlink        = ip6_tnl_newlink,
1727         .changelink     = ip6_tnl_changelink,
1728         .dellink        = ip6_tnl_dellink,
1729         .get_size       = ip6_tnl_get_size,
1730         .fill_info      = ip6_tnl_fill_info,
1731 };
1732
1733 static struct xfrm6_tunnel ip4ip6_handler __read_mostly = {
1734         .handler        = ip4ip6_rcv,
1735         .err_handler    = ip4ip6_err,
1736         .priority       =       1,
1737 };
1738
1739 static struct xfrm6_tunnel ip6ip6_handler __read_mostly = {
1740         .handler        = ip6ip6_rcv,
1741         .err_handler    = ip6ip6_err,
1742         .priority       =       1,
1743 };
1744
1745 static void __net_exit ip6_tnl_destroy_tunnels(struct net *net)
1746 {
1747         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1748         struct net_device *dev, *aux;
1749         int h;
1750         struct ip6_tnl *t;
1751         LIST_HEAD(list);
1752
1753         for_each_netdev_safe(net, dev, aux)
1754                 if (dev->rtnl_link_ops == &ip6_link_ops)
1755                         unregister_netdevice_queue(dev, &list);
1756
1757         for (h = 0; h < HASH_SIZE; h++) {
1758                 t = rtnl_dereference(ip6n->tnls_r_l[h]);
1759                 while (t != NULL) {
1760                         /* If dev is in the same netns, it has already
1761                          * been added to the list by the previous loop.
1762                          */
1763                         if (!net_eq(dev_net(t->dev), net))
1764                                 unregister_netdevice_queue(t->dev, &list);
1765                         t = rtnl_dereference(t->next);
1766                 }
1767         }
1768
1769         unregister_netdevice_many(&list);
1770 }
1771
1772 static int __net_init ip6_tnl_init_net(struct net *net)
1773 {
1774         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1775         struct ip6_tnl *t = NULL;
1776         int err;
1777
1778         ip6n->tnls[0] = ip6n->tnls_wc;
1779         ip6n->tnls[1] = ip6n->tnls_r_l;
1780
1781         err = -ENOMEM;
1782         ip6n->fb_tnl_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6tnl0",
1783                                       ip6_tnl_dev_setup);
1784
1785         if (!ip6n->fb_tnl_dev)
1786                 goto err_alloc_dev;
1787         dev_net_set(ip6n->fb_tnl_dev, net);
1788         ip6n->fb_tnl_dev->rtnl_link_ops = &ip6_link_ops;
1789         /* FB netdevice is special: we have one, and only one per netns.
1790          * Allowing to move it to another netns is clearly unsafe.
1791          */
1792         ip6n->fb_tnl_dev->features |= NETIF_F_NETNS_LOCAL;
1793
1794         err = ip6_fb_tnl_dev_init(ip6n->fb_tnl_dev);
1795         if (err < 0)
1796                 goto err_register;
1797
1798         err = register_netdev(ip6n->fb_tnl_dev);
1799         if (err < 0)
1800                 goto err_register;
1801
1802         t = netdev_priv(ip6n->fb_tnl_dev);
1803
1804         strcpy(t->parms.name, ip6n->fb_tnl_dev->name);
1805         return 0;
1806
1807 err_register:
1808         ip6_dev_free(ip6n->fb_tnl_dev);
1809 err_alloc_dev:
1810         return err;
1811 }
1812
1813 static void __net_exit ip6_tnl_exit_net(struct net *net)
1814 {
1815         rtnl_lock();
1816         ip6_tnl_destroy_tunnels(net);
1817         rtnl_unlock();
1818 }
1819
1820 static struct pernet_operations ip6_tnl_net_ops = {
1821         .init = ip6_tnl_init_net,
1822         .exit = ip6_tnl_exit_net,
1823         .id   = &ip6_tnl_net_id,
1824         .size = sizeof(struct ip6_tnl_net),
1825 };
1826
1827 /**
1828  * ip6_tunnel_init - register protocol and reserve needed resources
1829  *
1830  * Return: 0 on success
1831  **/
1832
1833 static int __init ip6_tunnel_init(void)
1834 {
1835         int  err;
1836
1837         err = register_pernet_device(&ip6_tnl_net_ops);
1838         if (err < 0)
1839                 goto out_pernet;
1840
1841         err = xfrm6_tunnel_register(&ip4ip6_handler, AF_INET);
1842         if (err < 0) {
1843                 pr_err("%s: can't register ip4ip6\n", __func__);
1844                 goto out_ip4ip6;
1845         }
1846
1847         err = xfrm6_tunnel_register(&ip6ip6_handler, AF_INET6);
1848         if (err < 0) {
1849                 pr_err("%s: can't register ip6ip6\n", __func__);
1850                 goto out_ip6ip6;
1851         }
1852         err = rtnl_link_register(&ip6_link_ops);
1853         if (err < 0)
1854                 goto rtnl_link_failed;
1855
1856         return 0;
1857
1858 rtnl_link_failed:
1859         xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6);
1860 out_ip6ip6:
1861         xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET);
1862 out_ip4ip6:
1863         unregister_pernet_device(&ip6_tnl_net_ops);
1864 out_pernet:
1865         return err;
1866 }
1867
1868 /**
1869  * ip6_tunnel_cleanup - free resources and unregister protocol
1870  **/
1871
1872 static void __exit ip6_tunnel_cleanup(void)
1873 {
1874         rtnl_link_unregister(&ip6_link_ops);
1875         if (xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET))
1876                 pr_info("%s: can't deregister ip4ip6\n", __func__);
1877
1878         if (xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6))
1879                 pr_info("%s: can't deregister ip6ip6\n", __func__);
1880
1881         unregister_pernet_device(&ip6_tnl_net_ops);
1882 }
1883
1884 module_init(ip6_tunnel_init);
1885 module_exit(ip6_tunnel_cleanup);