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 #include <net/dst_metadata.h>
  61
  62 MODULE_AUTHOR("Ville Nuorvala");
  63 MODULE_DESCRIPTION("IPv6 tunneling device");
  64 MODULE_LICENSE("GPL");
  65 MODULE_ALIAS_RTNL_LINK("ip6tnl");
  66 MODULE_ALIAS_NETDEV("ip6tnl0");
  67
  68 #define IP6_TUNNEL_HASH_SIZE_SHIFT  5
  69 #define IP6_TUNNEL_HASH_SIZE (1 << IP6_TUNNEL_HASH_SIZE_SHIFT)
  70
  71 static bool log_ecn_error = true;
  72 module_param(log_ecn_error, bool, 0644);
  73 MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");
  74
  75 static u32 HASH(const struct in6_addr *addr1, const struct in6_addr *addr2)
  76 {
  77         u32 hash = ipv6_addr_hash(addr1) ^ ipv6_addr_hash(addr2);
  78
  79         return hash_32(hash, IP6_TUNNEL_HASH_SIZE_SHIFT);
  80 }
  81
  82 static int ip6_tnl_dev_init(struct net_device *dev);
  83 static void ip6_tnl_dev_setup(struct net_device *dev);
  84 static struct rtnl_link_ops ip6_link_ops __read_mostly;
  85
  86 static int ip6_tnl_net_id __read_mostly;
  87 struct ip6_tnl_net {
  88         /* the IPv6 tunnel fallback device */
  89         struct net_device *fb_tnl_dev;
  90         /* lists for storing tunnels in use */
  91         struct ip6_tnl __rcu *tnls_r_l[IP6_TUNNEL_HASH_SIZE];
  92         struct ip6_tnl __rcu *tnls_wc[1];
  93         struct ip6_tnl __rcu **tnls[2];
  94         struct ip6_tnl __rcu *collect_md_tun;
  95 };
  96
  97 static struct net_device_stats *ip6_get_stats(struct net_device *dev)
  98 {
  99         struct pcpu_sw_netstats tmp, sum = { 0 };
 100         int i;
 101
 102         for_each_possible_cpu(i) {
 103                 unsigned int start;
 104                 const struct pcpu_sw_netstats *tstats =
 105                                                    per_cpu_ptr(dev->tstats, i);
 106
 107                 do {
 108                         start = u64_stats_fetch_begin_irq(&tstats->syncp);
 109                         tmp.rx_packets = tstats->rx_packets;
 110                         tmp.rx_bytes = tstats->rx_bytes;
 111                         tmp.tx_packets = tstats->tx_packets;
 112                         tmp.tx_bytes =  tstats->tx_bytes;
 113                 } while (u64_stats_fetch_retry_irq(&tstats->syncp, start));
 114
 115                 sum.rx_packets += tmp.rx_packets;
 116                 sum.rx_bytes   += tmp.rx_bytes;
 117                 sum.tx_packets += tmp.tx_packets;
 118                 sum.tx_bytes   += tmp.tx_bytes;
 119         }
 120         dev->stats.rx_packets = sum.rx_packets;
 121         dev->stats.rx_bytes   = sum.rx_bytes;
 122         dev->stats.tx_packets = sum.tx_packets;
 123         dev->stats.tx_bytes   = sum.tx_bytes;
 124         return &dev->stats;
 125 }
 126
 127 /**
 128  * ip6_tnl_lookup - fetch tunnel matching the end-point addresses
 129  *   @remote: the address of the tunnel exit-point
 130  *   @local: the address of the tunnel entry-point
 131  *
 132  * Return:
 133  *   tunnel matching given end-points if found,
 134  *   else fallback tunnel if its device is up,
 135  *   else %NULL
 136  **/
 137
 138 #define for_each_ip6_tunnel_rcu(start) \
 139         for (t = rcu_dereference(start); t; t = rcu_dereference(t->next))
 140
 141 static struct ip6_tnl *
 142 ip6_tnl_lookup(struct net *net, const struct in6_addr *remote, const struct in6_addr *local)
 143 {
 144         unsigned int hash = HASH(remote, local);
 145         struct ip6_tnl *t;
 146         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
 147         struct in6_addr any;
 148
 149         for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
 150                 if (ipv6_addr_equal(local, &t->parms.laddr) &&
 151                     ipv6_addr_equal(remote, &t->parms.raddr) &&
 152                     (t->dev->flags & IFF_UP))
 153                         return t;
 154         }
 155
 156         memset(&any, 0, sizeof(any));
 157         hash = HASH(&any, local);
 158         for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
 159                 if (ipv6_addr_equal(local, &t->parms.laddr) &&
 160                     ipv6_addr_any(&t->parms.raddr) &&
 161                     (t->dev->flags & IFF_UP))
 162                         return t;
 163         }
 164
 165         hash = HASH(remote, &any);
 166         for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
 167                 if (ipv6_addr_equal(remote, &t->parms.raddr) &&
 168                     ipv6_addr_any(&t->parms.laddr) &&
 169                     (t->dev->flags & IFF_UP))
 170                         return t;
 171         }
 172
 173         t = rcu_dereference(ip6n->collect_md_tun);
 174         if (t)
 175                 return t;
 176
 177         t = rcu_dereference(ip6n->tnls_wc[0]);
 178         if (t && (t->dev->flags & IFF_UP))
 179                 return t;
 180
 181         return NULL;
 182 }
 183
 184 /**
 185  * ip6_tnl_bucket - get head of list matching given tunnel parameters
 186  *   @p: parameters containing tunnel end-points
 187  *
 188  * Description:
 189  *   ip6_tnl_bucket() returns the head of the list matching the
 190  *   &struct in6_addr entries laddr and raddr in @p.
 191  *
 192  * Return: head of IPv6 tunnel list
 193  **/
 194
 195 static struct ip6_tnl __rcu **
 196 ip6_tnl_bucket(struct ip6_tnl_net *ip6n, const struct __ip6_tnl_parm *p)
 197 {
 198         const struct in6_addr *remote = &p->raddr;
 199         const struct in6_addr *local = &p->laddr;
 200         unsigned int h = 0;
 201         int prio = 0;
 202
 203         if (!ipv6_addr_any(remote) || !ipv6_addr_any(local)) {
 204                 prio = 1;
 205                 h = HASH(remote, local);
 206         }
 207         return &ip6n->tnls[prio][h];
 208 }
 209
 210 /**
 211  * ip6_tnl_link - add tunnel to hash table
 212  *   @t: tunnel to be added
 213  **/
 214
 215 static void
 216 ip6_tnl_link(struct ip6_tnl_net *ip6n, struct ip6_tnl *t)
 217 {
 218         struct ip6_tnl __rcu **tp = ip6_tnl_bucket(ip6n, &t->parms);
 219
 220         if (t->parms.collect_md)
 221                 rcu_assign_pointer(ip6n->collect_md_tun, t);
 222         rcu_assign_pointer(t->next , rtnl_dereference(*tp));
 223         rcu_assign_pointer(*tp, t);
 224 }
 225
 226 /**
 227  * ip6_tnl_unlink - remove tunnel from hash table
 228  *   @t: tunnel to be removed
 229  **/
 230
 231 static void
 232 ip6_tnl_unlink(struct ip6_tnl_net *ip6n, struct ip6_tnl *t)
 233 {
 234         struct ip6_tnl __rcu **tp;
 235         struct ip6_tnl *iter;
 236
 237         if (t->parms.collect_md)
 238                 rcu_assign_pointer(ip6n->collect_md_tun, NULL);
 239
 240         for (tp = ip6_tnl_bucket(ip6n, &t->parms);
 241              (iter = rtnl_dereference(*tp)) != NULL;
 242              tp = &iter->next) {
 243                 if (t == iter) {
 244                         rcu_assign_pointer(*tp, t->next);
 245                         break;
 246                 }
 247         }
 248 }
 249
 250 static void ip6_dev_free(struct net_device *dev)
 251 {
 252         struct ip6_tnl *t = netdev_priv(dev);
 253
 254         gro_cells_destroy(&t->gro_cells);
 255         dst_cache_destroy(&t->dst_cache);
 256         free_percpu(dev->tstats);
 257         free_netdev(dev);
 258 }
 259
 260 static int ip6_tnl_create2(struct net_device *dev)
 261 {
 262         struct ip6_tnl *t = netdev_priv(dev);
 263         struct net *net = dev_net(dev);
 264         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
 265         int err;
 266
 267         t = netdev_priv(dev);
 268
 269         dev->rtnl_link_ops = &ip6_link_ops;
 270         err = register_netdevice(dev);
 271         if (err < 0)
 272                 goto out;
 273
 274         strcpy(t->parms.name, dev->name);
 275
 276         dev_hold(dev);
 277         ip6_tnl_link(ip6n, t);
 278         return 0;
 279
 280 out:
 281         return err;
 282 }
 283
 284 /**
 285  * ip6_tnl_create - create a new tunnel
 286  *   @p: tunnel parameters
 287  *   @pt: pointer to new tunnel
 288  *
 289  * Description:
 290  *   Create tunnel matching given parameters.
 291  *
 292  * Return:
 293  *   created tunnel or error pointer
 294  **/
 295
 296 static struct ip6_tnl *ip6_tnl_create(struct net *net, struct __ip6_tnl_parm *p)
 297 {
 298         struct net_device *dev;
 299         struct ip6_tnl *t;
 300         char name[IFNAMSIZ];
 301         int err = -ENOMEM;
 302
 303         if (p->name[0])
 304                 strlcpy(name, p->name, IFNAMSIZ);
 305         else
 306                 sprintf(name, "ip6tnl%%d");
 307
 308         dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN,
 309                            ip6_tnl_dev_setup);
 310         if (!dev)
 311                 goto failed;
 312
 313         dev_net_set(dev, net);
 314
 315         t = netdev_priv(dev);
 316         t->parms = *p;
 317         t->net = dev_net(dev);
 318         err = ip6_tnl_create2(dev);
 319         if (err < 0)
 320                 goto failed_free;
 321
 322         return t;
 323
 324 failed_free:
 325         ip6_dev_free(dev);
 326 failed:
 327         return ERR_PTR(err);
 328 }
 329
 330 /**
 331  * ip6_tnl_locate - find or create tunnel matching given parameters
 332  *   @p: tunnel parameters
 333  *   @create: != 0 if allowed to create new tunnel if no match found
 334  *
 335  * Description:
 336  *   ip6_tnl_locate() first tries to locate an existing tunnel
 337  *   based on @parms. If this is unsuccessful, but @create is set a new
 338  *   tunnel device is created and registered for use.
 339  *
 340  * Return:
 341  *   matching tunnel or error pointer
 342  **/
 343
 344 static struct ip6_tnl *ip6_tnl_locate(struct net *net,
 345                 struct __ip6_tnl_parm *p, int create)
 346 {
 347         const struct in6_addr *remote = &p->raddr;
 348         const struct in6_addr *local = &p->laddr;
 349         struct ip6_tnl __rcu **tp;
 350         struct ip6_tnl *t;
 351         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
 352
 353         for (tp = ip6_tnl_bucket(ip6n, p);
 354              (t = rtnl_dereference(*tp)) != NULL;
 355              tp = &t->next) {
 356                 if (ipv6_addr_equal(local, &t->parms.laddr) &&
 357                     ipv6_addr_equal(remote, &t->parms.raddr)) {
 358                         if (create)
 359                                 return ERR_PTR(-EEXIST);
 360
 361                         return t;
 362                 }
 363         }
 364         if (!create)
 365                 return ERR_PTR(-ENODEV);
 366         return ip6_tnl_create(net, p);
 367 }
 368
 369 /**
 370  * ip6_tnl_dev_uninit - tunnel device uninitializer
 371  *   @dev: the device to be destroyed
 372  *
 373  * Description:
 374  *   ip6_tnl_dev_uninit() removes tunnel from its list
 375  **/
 376
 377 static void
 378 ip6_tnl_dev_uninit(struct net_device *dev)
 379 {
 380         struct ip6_tnl *t = netdev_priv(dev);
 381         struct net *net = t->net;
 382         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
 383
 384         if (dev == ip6n->fb_tnl_dev)
 385                 RCU_INIT_POINTER(ip6n->tnls_wc[0], NULL);
 386         else
 387                 ip6_tnl_unlink(ip6n, t);
 388         dst_cache_reset(&t->dst_cache);
 389         dev_put(dev);
 390 }
 391
 392 /**
 393  * parse_tvl_tnl_enc_lim - handle encapsulation limit option
 394  *   @skb: received socket buffer
 395  *
 396  * Return:
 397  *   0 if none was found,
 398  *   else index to encapsulation limit
 399  **/
 400
 401 __u16 ip6_tnl_parse_tlv_enc_lim(struct sk_buff *skb, __u8 *raw)
 402 {
 403         const struct ipv6hdr *ipv6h = (const struct ipv6hdr *) raw;
 404         __u8 nexthdr = ipv6h->nexthdr;
 405         __u16 off = sizeof(*ipv6h);
 406
 407         while (ipv6_ext_hdr(nexthdr) && nexthdr != NEXTHDR_NONE) {
 408                 __u16 optlen = 0;
 409                 struct ipv6_opt_hdr *hdr;
 410                 if (raw + off + sizeof(*hdr) > skb->data &&
 411                     !pskb_may_pull(skb, raw - skb->data + off + sizeof (*hdr)))
 412                         break;
 413
 414                 hdr = (struct ipv6_opt_hdr *) (raw + off);
 415                 if (nexthdr == NEXTHDR_FRAGMENT) {
 416                         struct frag_hdr *frag_hdr = (struct frag_hdr *) hdr;
 417                         if (frag_hdr->frag_off)
 418                                 break;
 419                         optlen = 8;
 420                 } else if (nexthdr == NEXTHDR_AUTH) {
 421                         optlen = (hdr->hdrlen + 2) << 2;
 422                 } else {
 423                         optlen = ipv6_optlen(hdr);
 424                 }
 425                 if (nexthdr == NEXTHDR_DEST) {
 426                         __u16 i = off + 2;
 427                         while (1) {
 428                                 struct ipv6_tlv_tnl_enc_lim *tel;
 429
 430                                 /* No more room for encapsulation limit */
 431                                 if (i + sizeof (*tel) > off + optlen)
 432                                         break;
 433
 434                                 tel = (struct ipv6_tlv_tnl_enc_lim *) &raw[i];
 435                                 /* return index of option if found and valid */
 436                                 if (tel->type == IPV6_TLV_TNL_ENCAP_LIMIT &&
 437                                     tel->length == 1)
 438                                         return i;
 439                                 /* else jump to next option */
 440                                 if (tel->type)
 441                                         i += tel->length + 2;
 442                                 else
 443                                         i++;
 444                         }
 445                 }
 446                 nexthdr = hdr->nexthdr;
 447                 off += optlen;
 448         }
 449         return 0;
 450 }
 451 EXPORT_SYMBOL(ip6_tnl_parse_tlv_enc_lim);
 452
 453 /**
 454  * ip6_tnl_err - tunnel error handler
 455  *
 456  * Description:
 457  *   ip6_tnl_err() should handle errors in the tunnel according
 458  *   to the specifications in RFC 2473.
 459  **/
 460
 461 static int
 462 ip6_tnl_err(struct sk_buff *skb, __u8 ipproto, struct inet6_skb_parm *opt,
 463             u8 *type, u8 *code, int *msg, __u32 *info, int offset)
 464 {
 465         const struct ipv6hdr *ipv6h = (const struct ipv6hdr *) skb->data;
 466         struct ip6_tnl *t;
 467         int rel_msg = 0;
 468         u8 rel_type = ICMPV6_DEST_UNREACH;
 469         u8 rel_code = ICMPV6_ADDR_UNREACH;
 470         u8 tproto;
 471         __u32 rel_info = 0;
 472         __u16 len;
 473         int err = -ENOENT;
 474
 475         /* If the packet doesn't contain the original IPv6 header we are
 476            in trouble since we might need the source address for further
 477            processing of the error. */
 478
 479         rcu_read_lock();
 480         t = ip6_tnl_lookup(dev_net(skb->dev), &ipv6h->daddr, &ipv6h->saddr);
 481         if (!t)
 482                 goto out;
 483
 484         tproto = ACCESS_ONCE(t->parms.proto);
 485         if (tproto != ipproto && tproto != 0)
 486                 goto out;
 487
 488         err = 0;
 489
 490         switch (*type) {
 491                 __u32 teli;
 492                 struct ipv6_tlv_tnl_enc_lim *tel;
 493                 __u32 mtu;
 494         case ICMPV6_DEST_UNREACH:
 495                 net_dbg_ratelimited("%s: Path to destination invalid or inactive!\n",
 496                                     t->parms.name);
 497                 rel_msg = 1;
 498                 break;
 499         case ICMPV6_TIME_EXCEED:
 500                 if ((*code) == ICMPV6_EXC_HOPLIMIT) {
 501                         net_dbg_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n",
 502                                             t->parms.name);
 503                         rel_msg = 1;
 504                 }
 505                 break;
 506         case ICMPV6_PARAMPROB:
 507                 teli = 0;
 508                 if ((*code) == ICMPV6_HDR_FIELD)
 509                         teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data);
 510
 511                 if (teli && teli == *info - 2) {
 512                         tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli];
 513                         if (tel->encap_limit == 0) {
 514                                 net_dbg_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n",
 515                                                     t->parms.name);
 516                                 rel_msg = 1;
 517                         }
 518                 } else {
 519                         net_dbg_ratelimited("%s: Recipient unable to parse tunneled packet!\n",
 520                                             t->parms.name);
 521                 }
 522                 break;
 523         case ICMPV6_PKT_TOOBIG:
 524                 mtu = *info - offset;
 525                 if (mtu < IPV6_MIN_MTU)
 526                         mtu = IPV6_MIN_MTU;
 527                 t->dev->mtu = mtu;
 528
 529                 len = sizeof(*ipv6h) + ntohs(ipv6h->payload_len);
 530                 if (len > mtu) {
 531                         rel_type = ICMPV6_PKT_TOOBIG;
 532                         rel_code = 0;
 533                         rel_info = mtu;
 534                         rel_msg = 1;
 535                 }
 536                 break;
 537         }
 538
 539         *type = rel_type;
 540         *code = rel_code;
 541         *info = rel_info;
 542         *msg = rel_msg;
 543
 544 out:
 545         rcu_read_unlock();
 546         return err;
 547 }
 548
 549 static int
 550 ip4ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 551            u8 type, u8 code, int offset, __be32 info)
 552 {
 553         int rel_msg = 0;
 554         u8 rel_type = type;
 555         u8 rel_code = code;
 556         __u32 rel_info = ntohl(info);
 557         int err;
 558         struct sk_buff *skb2;
 559         const struct iphdr *eiph;
 560         struct rtable *rt;
 561         struct flowi4 fl4;
 562
 563         err = ip6_tnl_err(skb, IPPROTO_IPIP, opt, &rel_type, &rel_code,
 564                           &rel_msg, &rel_info, offset);
 565         if (err < 0)
 566                 return err;
 567
 568         if (rel_msg == 0)
 569                 return 0;
 570
 571         switch (rel_type) {
 572         case ICMPV6_DEST_UNREACH:
 573                 if (rel_code != ICMPV6_ADDR_UNREACH)
 574                         return 0;
 575                 rel_type = ICMP_DEST_UNREACH;
 576                 rel_code = ICMP_HOST_UNREACH;
 577                 break;
 578         case ICMPV6_PKT_TOOBIG:
 579                 if (rel_code != 0)
 580                         return 0;
 581                 rel_type = ICMP_DEST_UNREACH;
 582                 rel_code = ICMP_FRAG_NEEDED;
 583                 break;
 584         case NDISC_REDIRECT:
 585                 rel_type = ICMP_REDIRECT;
 586                 rel_code = ICMP_REDIR_HOST;
 587         default:
 588                 return 0;
 589         }
 590
 591         if (!pskb_may_pull(skb, offset + sizeof(struct iphdr)))
 592                 return 0;
 593
 594         skb2 = skb_clone(skb, GFP_ATOMIC);
 595         if (!skb2)
 596                 return 0;
 597
 598         skb_dst_drop(skb2);
 599
 600         skb_pull(skb2, offset);
 601         skb_reset_network_header(skb2);
 602         eiph = ip_hdr(skb2);
 603
 604         /* Try to guess incoming interface */
 605         rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL,
 606                                    eiph->saddr, 0,
 607                                    0, 0,
 608                                    IPPROTO_IPIP, RT_TOS(eiph->tos), 0);
 609         if (IS_ERR(rt))
 610                 goto out;
 611
 612         skb2->dev = rt->dst.dev;
 613
 614         /* route "incoming" packet */
 615         if (rt->rt_flags & RTCF_LOCAL) {
 616                 ip_rt_put(rt);
 617                 rt = NULL;
 618                 rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL,
 619                                            eiph->daddr, eiph->saddr,
 620                                            0, 0,
 621                                            IPPROTO_IPIP,
 622                                            RT_TOS(eiph->tos), 0);
 623                 if (IS_ERR(rt) ||
 624                     rt->dst.dev->type != ARPHRD_TUNNEL) {
 625                         if (!IS_ERR(rt))
 626                                 ip_rt_put(rt);
 627                         goto out;
 628                 }
 629                 skb_dst_set(skb2, &rt->dst);
 630         } else {
 631                 ip_rt_put(rt);
 632                 if (ip_route_input(skb2, eiph->daddr, eiph->saddr, eiph->tos,
 633                                    skb2->dev) ||
 634                     skb_dst(skb2)->dev->type != ARPHRD_TUNNEL)
 635                         goto out;
 636         }
 637
 638         /* change mtu on this route */
 639         if (rel_type == ICMP_DEST_UNREACH && rel_code == ICMP_FRAG_NEEDED) {
 640                 if (rel_info > dst_mtu(skb_dst(skb2)))
 641                         goto out;
 642
 643                 skb_dst(skb2)->ops->update_pmtu(skb_dst(skb2), NULL, skb2, rel_info);
 644         }
 645         if (rel_type == ICMP_REDIRECT)
 646                 skb_dst(skb2)->ops->redirect(skb_dst(skb2), NULL, skb2);
 647
 648         icmp_send(skb2, rel_type, rel_code, htonl(rel_info));
 649
 650 out:
 651         kfree_skb(skb2);
 652         return 0;
 653 }
 654
 655 static int
 656 ip6ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 657            u8 type, u8 code, int offset, __be32 info)
 658 {
 659         int rel_msg = 0;
 660         u8 rel_type = type;
 661         u8 rel_code = code;
 662         __u32 rel_info = ntohl(info);
 663         int err;
 664
 665         err = ip6_tnl_err(skb, IPPROTO_IPV6, opt, &rel_type, &rel_code,
 666                           &rel_msg, &rel_info, offset);
 667         if (err < 0)
 668                 return err;
 669
 670         if (rel_msg && pskb_may_pull(skb, offset + sizeof(struct ipv6hdr))) {
 671                 struct rt6_info *rt;
 672                 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
 673
 674                 if (!skb2)
 675                         return 0;
 676
 677                 skb_dst_drop(skb2);
 678                 skb_pull(skb2, offset);
 679                 skb_reset_network_header(skb2);
 680
 681                 /* Try to guess incoming interface */
 682                 rt = rt6_lookup(dev_net(skb->dev), &ipv6_hdr(skb2)->saddr,
 683                                 NULL, 0, 0);
 684
 685                 if (rt && rt->dst.dev)
 686                         skb2->dev = rt->dst.dev;
 687
 688                 icmpv6_send(skb2, rel_type, rel_code, rel_info);
 689
 690                 ip6_rt_put(rt);
 691
 692                 kfree_skb(skb2);
 693         }
 694
 695         return 0;
 696 }
 697
 698 static int ip4ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t,
 699                                        const struct ipv6hdr *ipv6h,
 700                                        struct sk_buff *skb)
 701 {
 702         __u8 dsfield = ipv6_get_dsfield(ipv6h) & ~INET_ECN_MASK;
 703
 704         if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY)
 705                 ipv4_change_dsfield(ip_hdr(skb), INET_ECN_MASK, dsfield);
 706
 707         return IP6_ECN_decapsulate(ipv6h, skb);
 708 }
 709
 710 static int ip6ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t,
 711                                        const struct ipv6hdr *ipv6h,
 712                                        struct sk_buff *skb)
 713 {
 714         if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY)
 715                 ipv6_copy_dscp(ipv6_get_dsfield(ipv6h), ipv6_hdr(skb));
 716
 717         return IP6_ECN_decapsulate(ipv6h, skb);
 718 }
 719
 720 __u32 ip6_tnl_get_cap(struct ip6_tnl *t,
 721                              const struct in6_addr *laddr,
 722                              const struct in6_addr *raddr)
 723 {
 724         struct __ip6_tnl_parm *p = &t->parms;
 725         int ltype = ipv6_addr_type(laddr);
 726         int rtype = ipv6_addr_type(raddr);
 727         __u32 flags = 0;
 728
 729         if (ltype == IPV6_ADDR_ANY || rtype == IPV6_ADDR_ANY) {
 730                 flags = IP6_TNL_F_CAP_PER_PACKET;
 731         } else if (ltype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) &&
 732                    rtype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) &&
 733                    !((ltype|rtype) & IPV6_ADDR_LOOPBACK) &&
 734                    (!((ltype|rtype) & IPV6_ADDR_LINKLOCAL) || p->link)) {
 735                 if (ltype&IPV6_ADDR_UNICAST)
 736                         flags |= IP6_TNL_F_CAP_XMIT;
 737                 if (rtype&IPV6_ADDR_UNICAST)
 738                         flags |= IP6_TNL_F_CAP_RCV;
 739         }
 740         return flags;
 741 }
 742 EXPORT_SYMBOL(ip6_tnl_get_cap);
 743
 744 /* called with rcu_read_lock() */
 745 int ip6_tnl_rcv_ctl(struct ip6_tnl *t,
 746                                   const struct in6_addr *laddr,
 747                                   const struct in6_addr *raddr)
 748 {
 749         struct __ip6_tnl_parm *p = &t->parms;
 750         int ret = 0;
 751         struct net *net = t->net;
 752
 753         if ((p->flags & IP6_TNL_F_CAP_RCV) ||
 754             ((p->flags & IP6_TNL_F_CAP_PER_PACKET) &&
 755              (ip6_tnl_get_cap(t, laddr, raddr) & IP6_TNL_F_CAP_RCV))) {
 756                 struct net_device *ldev = NULL;
 757
 758                 if (p->link)
 759                         ldev = dev_get_by_index_rcu(net, p->link);
 760
 761                 if ((ipv6_addr_is_multicast(laddr) ||
 762                      likely(ipv6_chk_addr(net, laddr, ldev, 0))) &&
 763                     likely(!ipv6_chk_addr(net, raddr, NULL, 0)))
 764                         ret = 1;
 765         }
 766         return ret;
 767 }
 768 EXPORT_SYMBOL_GPL(ip6_tnl_rcv_ctl);
 769
 770 static int __ip6_tnl_rcv(struct ip6_tnl *tunnel, struct sk_buff *skb,
 771                          const struct tnl_ptk_info *tpi,
 772                          struct metadata_dst *tun_dst,
 773                          int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t,
 774                                                 const struct ipv6hdr *ipv6h,
 775                                                 struct sk_buff *skb),
 776                          bool log_ecn_err)
 777 {
 778         struct pcpu_sw_netstats *tstats;
 779         const struct ipv6hdr *ipv6h = ipv6_hdr(skb);
 780         int err;
 781
 782         if ((!(tpi->flags & TUNNEL_CSUM) &&
 783              (tunnel->parms.i_flags & TUNNEL_CSUM)) ||
 784             ((tpi->flags & TUNNEL_CSUM) &&
 785              !(tunnel->parms.i_flags & TUNNEL_CSUM))) {
 786                 tunnel->dev->stats.rx_crc_errors++;
 787                 tunnel->dev->stats.rx_errors++;
 788                 goto drop;
 789         }
 790
 791         if (tunnel->parms.i_flags & TUNNEL_SEQ) {
 792                 if (!(tpi->flags & TUNNEL_SEQ) ||
 793                     (tunnel->i_seqno &&
 794                      (s32)(ntohl(tpi->seq) - tunnel->i_seqno) < 0)) {
 795                         tunnel->dev->stats.rx_fifo_errors++;
 796                         tunnel->dev->stats.rx_errors++;
 797                         goto drop;
 798                 }
 799                 tunnel->i_seqno = ntohl(tpi->seq) + 1;
 800         }
 801
 802         skb->protocol = tpi->proto;
 803
 804         /* Warning: All skb pointers will be invalidated! */
 805         if (tunnel->dev->type == ARPHRD_ETHER) {
 806                 if (!pskb_may_pull(skb, ETH_HLEN)) {
 807                         tunnel->dev->stats.rx_length_errors++;
 808                         tunnel->dev->stats.rx_errors++;
 809                         goto drop;
 810                 }
 811
 812                 ipv6h = ipv6_hdr(skb);
 813                 skb->protocol = eth_type_trans(skb, tunnel->dev);
 814                 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);
 815         } else {
 816                 skb->dev = tunnel->dev;
 817         }
 818
 819         skb_reset_network_header(skb);
 820         memset(skb->cb, 0, sizeof(struct inet6_skb_parm));
 821
 822         __skb_tunnel_rx(skb, tunnel->dev, tunnel->net);
 823
 824         err = dscp_ecn_decapsulate(tunnel, ipv6h, skb);
 825         if (unlikely(err)) {
 826                 if (log_ecn_err)
 827                         net_info_ratelimited("non-ECT from %pI6 with DS=%#x\n",
 828                                              &ipv6h->saddr,
 829                                              ipv6_get_dsfield(ipv6h));
 830                 if (err > 1) {
 831                         ++tunnel->dev->stats.rx_frame_errors;
 832                         ++tunnel->dev->stats.rx_errors;
 833                         goto drop;
 834                 }
 835         }
 836
 837         tstats = this_cpu_ptr(tunnel->dev->tstats);
 838         u64_stats_update_begin(&tstats->syncp);
 839         tstats->rx_packets++;
 840         tstats->rx_bytes += skb->len;
 841         u64_stats_update_end(&tstats->syncp);
 842
 843         skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(tunnel->dev)));
 844
 845         if (tun_dst)
 846                 skb_dst_set(skb, (struct dst_entry *)tun_dst);
 847
 848         gro_cells_receive(&tunnel->gro_cells, skb);
 849         return 0;
 850
 851 drop:
 852         kfree_skb(skb);
 853         return 0;
 854 }
 855
 856 int ip6_tnl_rcv(struct ip6_tnl *t, struct sk_buff *skb,
 857                 const struct tnl_ptk_info *tpi,
 858                 struct metadata_dst *tun_dst,
 859                 bool log_ecn_err)
 860 {
 861         return __ip6_tnl_rcv(t, skb, tpi, NULL, ip6ip6_dscp_ecn_decapsulate,
 862                              log_ecn_err);
 863 }
 864 EXPORT_SYMBOL(ip6_tnl_rcv);
 865
 866 static const struct tnl_ptk_info tpi_v6 = {
 867         /* no tunnel info required for ipxip6. */
 868         .proto = htons(ETH_P_IPV6),
 869 };
 870
 871 static const struct tnl_ptk_info tpi_v4 = {
 872         /* no tunnel info required for ipxip6. */
 873         .proto = htons(ETH_P_IP),
 874 };
 875
 876 static int ipxip6_rcv(struct sk_buff *skb, u8 ipproto,
 877                       const struct tnl_ptk_info *tpi,
 878                       int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t,
 879                                                   const struct ipv6hdr *ipv6h,
 880                                                   struct sk_buff *skb))
 881 {
 882         struct ip6_tnl *t;
 883         const struct ipv6hdr *ipv6h = ipv6_hdr(skb);
 884         struct metadata_dst *tun_dst = NULL;
 885         int ret = -1;
 886
 887         rcu_read_lock();
 888         t = ip6_tnl_lookup(dev_net(skb->dev), &ipv6h->saddr, &ipv6h->daddr);
 889
 890         if (t) {
 891                 u8 tproto = ACCESS_ONCE(t->parms.proto);
 892
 893                 if (tproto != ipproto && tproto != 0)
 894                         goto drop;
 895                 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
 896                         goto drop;
 897                 if (!ip6_tnl_rcv_ctl(t, &ipv6h->daddr, &ipv6h->saddr))
 898                         goto drop;
 899                 if (iptunnel_pull_header(skb, 0, tpi->proto, false))
 900                         goto drop;
 901                 if (t->parms.collect_md) {
 902                         tun_dst = ipv6_tun_rx_dst(skb, 0, 0, 0);
 903                         if (!tun_dst)
 904                                 return 0;
 905                 }
 906                 ret = __ip6_tnl_rcv(t, skb, tpi, tun_dst, dscp_ecn_decapsulate,
 907                                     log_ecn_error);
 908         }
 909
 910         rcu_read_unlock();
 911
 912         return ret;
 913
 914 drop:
 915         rcu_read_unlock();
 916         kfree_skb(skb);
 917         return 0;
 918 }
 919
 920 static int ip4ip6_rcv(struct sk_buff *skb)
 921 {
 922         return ipxip6_rcv(skb, IPPROTO_IPIP, &tpi_v4,
 923                           ip4ip6_dscp_ecn_decapsulate);
 924 }
 925
 926 static int ip6ip6_rcv(struct sk_buff *skb)
 927 {
 928         return ipxip6_rcv(skb, IPPROTO_IPV6, &tpi_v6,
 929                           ip6ip6_dscp_ecn_decapsulate);
 930 }
 931
 932 struct ipv6_tel_txoption {
 933         struct ipv6_txoptions ops;
 934         __u8 dst_opt[8];
 935 };
 936
 937 static void init_tel_txopt(struct ipv6_tel_txoption *opt, __u8 encap_limit)
 938 {
 939         memset(opt, 0, sizeof(struct ipv6_tel_txoption));
 940
 941         opt->dst_opt[2] = IPV6_TLV_TNL_ENCAP_LIMIT;
 942         opt->dst_opt[3] = 1;
 943         opt->dst_opt[4] = encap_limit;
 944         opt->dst_opt[5] = IPV6_TLV_PADN;
 945         opt->dst_opt[6] = 1;
 946
 947         opt->ops.dst0opt = (struct ipv6_opt_hdr *) opt->dst_opt;
 948         opt->ops.opt_nflen = 8;
 949 }
 950
 951 /**
 952  * ip6_tnl_addr_conflict - compare packet addresses to tunnel's own
 953  *   @t: the outgoing tunnel device
 954  *   @hdr: IPv6 header from the incoming packet
 955  *
 956  * Description:
 957  *   Avoid trivial tunneling loop by checking that tunnel exit-point
 958  *   doesn't match source of incoming packet.
 959  *
 960  * Return:
 961  *   1 if conflict,
 962  *   0 else
 963  **/
 964
 965 static inline bool
 966 ip6_tnl_addr_conflict(const struct ip6_tnl *t, const struct ipv6hdr *hdr)
 967 {
 968         return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr);
 969 }
 970
 971 int ip6_tnl_xmit_ctl(struct ip6_tnl *t,
 972                      const struct in6_addr *laddr,
 973                      const struct in6_addr *raddr)
 974 {
 975         struct __ip6_tnl_parm *p = &t->parms;
 976         int ret = 0;
 977         struct net *net = t->net;
 978
 979         if ((p->flags & IP6_TNL_F_CAP_XMIT) ||
 980             ((p->flags & IP6_TNL_F_CAP_PER_PACKET) &&
 981              (ip6_tnl_get_cap(t, laddr, raddr) & IP6_TNL_F_CAP_XMIT))) {
 982                 struct net_device *ldev = NULL;
 983
 984                 rcu_read_lock();
 985                 if (p->link)
 986                         ldev = dev_get_by_index_rcu(net, p->link);
 987
 988                 if (unlikely(!ipv6_chk_addr(net, laddr, ldev, 0)))
 989                         pr_warn("%s xmit: Local address not yet configured!\n",
 990                                 p->name);
 991                 else if (!ipv6_addr_is_multicast(raddr) &&
 992                          unlikely(ipv6_chk_addr(net, raddr, NULL, 0)))
 993                         pr_warn("%s xmit: Routing loop! Remote address found on this node!\n",
 994                                 p->name);
 995                 else
 996                         ret = 1;
 997                 rcu_read_unlock();
 998         }
 999         return ret;
1000 }
1001 EXPORT_SYMBOL_GPL(ip6_tnl_xmit_ctl);
1002
1003 /**
1004  * ip6_tnl_xmit - encapsulate packet and send
1005  *   @skb: the outgoing socket buffer
1006  *   @dev: the outgoing tunnel device
1007  *   @dsfield: dscp code for outer header
1008  *   @fl6: flow of tunneled packet
1009  *   @encap_limit: encapsulation limit
1010  *   @pmtu: Path MTU is stored if packet is too big
1011  *   @proto: next header value
1012  *
1013  * Description:
1014  *   Build new header and do some sanity checks on the packet before sending
1015  *   it.
1016  *
1017  * Return:
1018  *   0 on success
1019  *   -1 fail
1020  *   %-EMSGSIZE message too big. return mtu in this case.
1021  **/
1022
1023 int ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev, __u8 dsfield,
1024                  struct flowi6 *fl6, int encap_limit, __u32 *pmtu,
1025                  __u8 proto)
1026 {
1027         struct ip6_tnl *t = netdev_priv(dev);
1028         struct net *net = t->net;
1029         struct net_device_stats *stats = &t->dev->stats;
1030         struct ipv6hdr *ipv6h = ipv6_hdr(skb);
1031         struct ipv6_tel_txoption opt;
1032         struct dst_entry *dst = NULL, *ndst = NULL;
1033         struct net_device *tdev;
1034         int mtu;
1035         unsigned int psh_hlen = sizeof(struct ipv6hdr) + t->encap_hlen;
1036         unsigned int max_headroom = psh_hlen;
1037         u8 hop_limit;
1038         int err = -1;
1039
1040         if (t->parms.collect_md) {
1041                 hop_limit = skb_tunnel_info(skb)->key.ttl;
1042                 goto route_lookup;
1043         } else {
1044                 hop_limit = t->parms.hop_limit;
1045         }
1046
1047         /* NBMA tunnel */
1048         if (ipv6_addr_any(&t->parms.raddr)) {
1049                 struct in6_addr *addr6;
1050                 struct neighbour *neigh;
1051                 int addr_type;
1052
1053                 if (!skb_dst(skb))
1054                         goto tx_err_link_failure;
1055
1056                 neigh = dst_neigh_lookup(skb_dst(skb),
1057                                          &ipv6_hdr(skb)->daddr);
1058                 if (!neigh)
1059                         goto tx_err_link_failure;
1060
1061                 addr6 = (struct in6_addr *)&neigh->primary_key;
1062                 addr_type = ipv6_addr_type(addr6);
1063
1064                 if (addr_type == IPV6_ADDR_ANY)
1065                         addr6 = &ipv6_hdr(skb)->daddr;
1066
1067                 memcpy(&fl6->daddr, addr6, sizeof(fl6->daddr));
1068                 neigh_release(neigh);
1069         } else if (!fl6->flowi6_mark)
1070                 dst = dst_cache_get(&t->dst_cache);
1071
1072         if (!ip6_tnl_xmit_ctl(t, &fl6->saddr, &fl6->daddr))
1073                 goto tx_err_link_failure;
1074
1075         if (!dst) {
1076 route_lookup:
1077                 dst = ip6_route_output(net, NULL, fl6);
1078
1079                 if (dst->error)
1080                         goto tx_err_link_failure;
1081                 dst = xfrm_lookup(net, dst, flowi6_to_flowi(fl6), NULL, 0);
1082                 if (IS_ERR(dst)) {
1083                         err = PTR_ERR(dst);
1084                         dst = NULL;
1085                         goto tx_err_link_failure;
1086                 }
1087                 if (t->parms.collect_md &&
1088                     ipv6_dev_get_saddr(net, ip6_dst_idev(dst)->dev,
1089                                        &fl6->daddr, 0, &fl6->saddr))
1090                         goto tx_err_link_failure;
1091                 ndst = dst;
1092         }
1093
1094         tdev = dst->dev;
1095
1096         if (tdev == dev) {
1097                 stats->collisions++;
1098                 net_warn_ratelimited("%s: Local routing loop detected!\n",
1099                                      t->parms.name);
1100                 goto tx_err_dst_release;
1101         }
1102         mtu = dst_mtu(dst) - psh_hlen;
1103         if (encap_limit >= 0) {
1104                 max_headroom += 8;
1105                 mtu -= 8;
1106         }
1107         if (mtu < IPV6_MIN_MTU)
1108                 mtu = IPV6_MIN_MTU;
1109         if (skb_dst(skb) && !t->parms.collect_md)
1110                 skb_dst(skb)->ops->update_pmtu(skb_dst(skb), NULL, skb, mtu);
1111         if (skb->len > mtu && !skb_is_gso(skb)) {
1112                 *pmtu = mtu;
1113                 err = -EMSGSIZE;
1114                 goto tx_err_dst_release;
1115         }
1116
1117         if (t->err_count > 0) {
1118                 if (time_before(jiffies,
1119                                 t->err_time + IP6TUNNEL_ERR_TIMEO)) {
1120                         t->err_count--;
1121
1122                         dst_link_failure(skb);
1123                 } else {
1124                         t->err_count = 0;
1125                 }
1126         }
1127
1128         skb_scrub_packet(skb, !net_eq(t->net, dev_net(dev)));
1129
1130         /*
1131          * Okay, now see if we can stuff it in the buffer as-is.
1132          */
1133         max_headroom += LL_RESERVED_SPACE(tdev);
1134
1135         if (skb_headroom(skb) < max_headroom || skb_shared(skb) ||
1136             (skb_cloned(skb) && !skb_clone_writable(skb, 0))) {
1137                 struct sk_buff *new_skb;
1138
1139                 new_skb = skb_realloc_headroom(skb, max_headroom);
1140                 if (!new_skb)
1141                         goto tx_err_dst_release;
1142
1143                 if (skb->sk)
1144                         skb_set_owner_w(new_skb, skb->sk);
1145                 consume_skb(skb);
1146                 skb = new_skb;
1147         }
1148
1149         if (t->parms.collect_md) {
1150                 if (t->encap.type != TUNNEL_ENCAP_NONE)
1151                         goto tx_err_dst_release;
1152         } else {
1153                 if (!fl6->flowi6_mark && ndst)
1154                         dst_cache_set_ip6(&t->dst_cache, ndst, &fl6->saddr);
1155         }
1156         skb_dst_set(skb, dst);
1157
1158         if (encap_limit >= 0) {
1159                 init_tel_txopt(&opt, encap_limit);
1160                 ipv6_push_nfrag_opts(skb, &opt.ops, &proto, NULL);
1161         }
1162
1163         /* Calculate max headroom for all the headers and adjust
1164          * needed_headroom if necessary.
1165          */
1166         max_headroom = LL_RESERVED_SPACE(dst->dev) + sizeof(struct ipv6hdr)
1167                         + dst->header_len + t->hlen;
1168         if (max_headroom > dev->needed_headroom)
1169                 dev->needed_headroom = max_headroom;
1170
1171         err = ip6_tnl_encap(skb, t, &proto, fl6);
1172         if (err)
1173                 return err;
1174
1175         skb_push(skb, sizeof(struct ipv6hdr));
1176         skb_reset_network_header(skb);
1177         ipv6h = ipv6_hdr(skb);
1178         ip6_flow_hdr(ipv6h, INET_ECN_encapsulate(0, dsfield),
1179                      ip6_make_flowlabel(net, skb, fl6->flowlabel, true, fl6));
1180         ipv6h->hop_limit = hop_limit;
1181         ipv6h->nexthdr = proto;
1182         ipv6h->saddr = fl6->saddr;
1183         ipv6h->daddr = fl6->daddr;
1184         ip6tunnel_xmit(NULL, skb, dev);
1185         return 0;
1186 tx_err_link_failure:
1187         stats->tx_carrier_errors++;
1188         dst_link_failure(skb);
1189 tx_err_dst_release:
1190         dst_release(dst);
1191         return err;
1192 }
1193 EXPORT_SYMBOL(ip6_tnl_xmit);
1194
1195 static inline int
1196 ip4ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev)
1197 {
1198         struct ip6_tnl *t = netdev_priv(dev);
1199         const struct iphdr  *iph = ip_hdr(skb);
1200         int encap_limit = -1;
1201         struct flowi6 fl6;
1202         __u8 dsfield;
1203         __u32 mtu;
1204         u8 tproto;
1205         int err;
1206
1207         memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
1208
1209         tproto = ACCESS_ONCE(t->parms.proto);
1210         if (tproto != IPPROTO_IPIP && tproto != 0)
1211                 return -1;
1212
1213         dsfield = ipv4_get_dsfield(iph);
1214
1215         if (t->parms.collect_md) {
1216                 struct ip_tunnel_info *tun_info;
1217                 const struct ip_tunnel_key *key;
1218
1219                 tun_info = skb_tunnel_info(skb);
1220                 if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) ||
1221                              ip_tunnel_info_af(tun_info) != AF_INET6))
1222                         return -1;
1223                 key = &tun_info->key;
1224                 memset(&fl6, 0, sizeof(fl6));
1225                 fl6.flowi6_proto = IPPROTO_IPIP;
1226                 fl6.daddr = key->u.ipv6.dst;
1227                 fl6.flowlabel = key->label;
1228         } else {
1229                 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1230                         encap_limit = t->parms.encap_limit;
1231
1232                 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
1233                 fl6.flowi6_proto = IPPROTO_IPIP;
1234
1235                 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
1236                         fl6.flowlabel |= htonl((__u32)iph->tos << IPV6_TCLASS_SHIFT)
1237                                          & IPV6_TCLASS_MASK;
1238                 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
1239                         fl6.flowi6_mark = skb->mark;
1240         }
1241
1242         if (iptunnel_handle_offloads(skb, SKB_GSO_IPXIP6))
1243                 return -1;
1244
1245         skb_set_inner_ipproto(skb, IPPROTO_IPIP);
1246
1247         err = ip6_tnl_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu,
1248                            IPPROTO_IPIP);
1249         if (err != 0) {
1250                 /* XXX: send ICMP error even if DF is not set. */
1251                 if (err == -EMSGSIZE)
1252                         icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
1253                                   htonl(mtu));
1254                 return -1;
1255         }
1256
1257         return 0;
1258 }
1259
1260 static inline int
1261 ip6ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev)
1262 {
1263         struct ip6_tnl *t = netdev_priv(dev);
1264         struct ipv6hdr *ipv6h = ipv6_hdr(skb);
1265         int encap_limit = -1;
1266         __u16 offset;
1267         struct flowi6 fl6;
1268         __u8 dsfield;
1269         __u32 mtu;
1270         u8 tproto;
1271         int err;
1272
1273         tproto = ACCESS_ONCE(t->parms.proto);
1274         if ((tproto != IPPROTO_IPV6 && tproto != 0) ||
1275             ip6_tnl_addr_conflict(t, ipv6h))
1276                 return -1;
1277
1278         dsfield = ipv6_get_dsfield(ipv6h);
1279
1280         if (t->parms.collect_md) {
1281                 struct ip_tunnel_info *tun_info;
1282                 const struct ip_tunnel_key *key;
1283
1284                 tun_info = skb_tunnel_info(skb);
1285                 if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) ||
1286                              ip_tunnel_info_af(tun_info) != AF_INET6))
1287                         return -1;
1288                 key = &tun_info->key;
1289                 memset(&fl6, 0, sizeof(fl6));
1290                 fl6.flowi6_proto = IPPROTO_IPV6;
1291                 fl6.daddr = key->u.ipv6.dst;
1292                 fl6.flowlabel = key->label;
1293         } else {
1294                 offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb));
1295                 if (offset > 0) {
1296                         struct ipv6_tlv_tnl_enc_lim *tel;
1297
1298                         tel = (void *)&skb_network_header(skb)[offset];
1299                         if (tel->encap_limit == 0) {
1300                                 icmpv6_send(skb, ICMPV6_PARAMPROB,
1301                                             ICMPV6_HDR_FIELD, offset + 2);
1302                                 return -1;
1303                         }
1304                         encap_limit = tel->encap_limit - 1;
1305                 } else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) {
1306                         encap_limit = t->parms.encap_limit;
1307                 }
1308
1309                 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
1310                 fl6.flowi6_proto = IPPROTO_IPV6;
1311
1312                 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
1313                         fl6.flowlabel |= (*(__be32 *)ipv6h & IPV6_TCLASS_MASK);
1314                 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL)
1315                         fl6.flowlabel |= ip6_flowlabel(ipv6h);
1316                 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
1317                         fl6.flowi6_mark = skb->mark;
1318         }
1319
1320         if (iptunnel_handle_offloads(skb, SKB_GSO_IPXIP6))
1321                 return -1;
1322
1323         skb_set_inner_ipproto(skb, IPPROTO_IPV6);
1324
1325         err = ip6_tnl_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu,
1326                            IPPROTO_IPV6);
1327         if (err != 0) {
1328                 if (err == -EMSGSIZE)
1329                         icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
1330                 return -1;
1331         }
1332
1333         return 0;
1334 }
1335
1336 static netdev_tx_t
1337 ip6_tnl_start_xmit(struct sk_buff *skb, struct net_device *dev)
1338 {
1339         struct ip6_tnl *t = netdev_priv(dev);
1340         struct net_device_stats *stats = &t->dev->stats;
1341         int ret;
1342
1343         switch (skb->protocol) {
1344         case htons(ETH_P_IP):
1345                 ret = ip4ip6_tnl_xmit(skb, dev);
1346                 break;
1347         case htons(ETH_P_IPV6):
1348                 ret = ip6ip6_tnl_xmit(skb, dev);
1349                 break;
1350         default:
1351                 goto tx_err;
1352         }
1353
1354         if (ret < 0)
1355                 goto tx_err;
1356
1357         return NETDEV_TX_OK;
1358
1359 tx_err:
1360         stats->tx_errors++;
1361         stats->tx_dropped++;
1362         kfree_skb(skb);
1363         return NETDEV_TX_OK;
1364 }
1365
1366 static void ip6_tnl_link_config(struct ip6_tnl *t)
1367 {
1368         struct net_device *dev = t->dev;
1369         struct __ip6_tnl_parm *p = &t->parms;
1370         struct flowi6 *fl6 = &t->fl.u.ip6;
1371         int t_hlen;
1372
1373         memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr));
1374         memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr));
1375
1376         /* Set up flowi template */
1377         fl6->saddr = p->laddr;
1378         fl6->daddr = p->raddr;
1379         fl6->flowi6_oif = p->link;
1380         fl6->flowlabel = 0;
1381
1382         if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS))
1383                 fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo;
1384         if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL))
1385                 fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo;
1386
1387         p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET);
1388         p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr);
1389
1390         if (p->flags&IP6_TNL_F_CAP_XMIT && p->flags&IP6_TNL_F_CAP_RCV)
1391                 dev->flags |= IFF_POINTOPOINT;
1392         else
1393                 dev->flags &= ~IFF_POINTOPOINT;
1394
1395         t->tun_hlen = 0;
1396         t->hlen = t->encap_hlen + t->tun_hlen;
1397         t_hlen = t->hlen + sizeof(struct ipv6hdr);
1398
1399         if (p->flags & IP6_TNL_F_CAP_XMIT) {
1400                 int strict = (ipv6_addr_type(&p->raddr) &
1401                               (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL));
1402
1403                 struct rt6_info *rt = rt6_lookup(t->net,
1404                                                  &p->raddr, &p->laddr,
1405                                                  p->link, strict);
1406
1407                 if (!rt)
1408                         return;
1409
1410                 if (rt->dst.dev) {
1411                         dev->hard_header_len = rt->dst.dev->hard_header_len +
1412                                 t_hlen;
1413
1414                         dev->mtu = rt->dst.dev->mtu - t_hlen;
1415                         if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1416                                 dev->mtu -= 8;
1417
1418                         if (dev->mtu < IPV6_MIN_MTU)
1419                                 dev->mtu = IPV6_MIN_MTU;
1420                 }
1421                 ip6_rt_put(rt);
1422         }
1423 }
1424
1425 /**
1426  * ip6_tnl_change - update the tunnel parameters
1427  *   @t: tunnel to be changed
1428  *   @p: tunnel configuration parameters
1429  *
1430  * Description:
1431  *   ip6_tnl_change() updates the tunnel parameters
1432  **/
1433
1434 static int
1435 ip6_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p)
1436 {
1437         t->parms.laddr = p->laddr;
1438         t->parms.raddr = p->raddr;
1439         t->parms.flags = p->flags;
1440         t->parms.hop_limit = p->hop_limit;
1441         t->parms.encap_limit = p->encap_limit;
1442         t->parms.flowinfo = p->flowinfo;
1443         t->parms.link = p->link;
1444         t->parms.proto = p->proto;
1445         dst_cache_reset(&t->dst_cache);
1446         ip6_tnl_link_config(t);
1447         return 0;
1448 }
1449
1450 static int ip6_tnl_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p)
1451 {
1452         struct net *net = t->net;
1453         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1454         int err;
1455
1456         ip6_tnl_unlink(ip6n, t);
1457         synchronize_net();
1458         err = ip6_tnl_change(t, p);
1459         ip6_tnl_link(ip6n, t);
1460         netdev_state_change(t->dev);
1461         return err;
1462 }
1463
1464 static int ip6_tnl0_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p)
1465 {
1466         /* for default tnl0 device allow to change only the proto */
1467         t->parms.proto = p->proto;
1468         netdev_state_change(t->dev);
1469         return 0;
1470 }
1471
1472 static void
1473 ip6_tnl_parm_from_user(struct __ip6_tnl_parm *p, const struct ip6_tnl_parm *u)
1474 {
1475         p->laddr = u->laddr;
1476         p->raddr = u->raddr;
1477         p->flags = u->flags;
1478         p->hop_limit = u->hop_limit;
1479         p->encap_limit = u->encap_limit;
1480         p->flowinfo = u->flowinfo;
1481         p->link = u->link;
1482         p->proto = u->proto;
1483         memcpy(p->name, u->name, sizeof(u->name));
1484 }
1485
1486 static void
1487 ip6_tnl_parm_to_user(struct ip6_tnl_parm *u, const struct __ip6_tnl_parm *p)
1488 {
1489         u->laddr = p->laddr;
1490         u->raddr = p->raddr;
1491         u->flags = p->flags;
1492         u->hop_limit = p->hop_limit;
1493         u->encap_limit = p->encap_limit;
1494         u->flowinfo = p->flowinfo;
1495         u->link = p->link;
1496         u->proto = p->proto;
1497         memcpy(u->name, p->name, sizeof(u->name));
1498 }
1499
1500 /**
1501  * ip6_tnl_ioctl - configure ipv6 tunnels from userspace
1502  *   @dev: virtual device associated with tunnel
1503  *   @ifr: parameters passed from userspace
1504  *   @cmd: command to be performed
1505  *
1506  * Description:
1507  *   ip6_tnl_ioctl() is used for managing IPv6 tunnels
1508  *   from userspace.
1509  *
1510  *   The possible commands are the following:
1511  *     %SIOCGETTUNNEL: get tunnel parameters for device
1512  *     %SIOCADDTUNNEL: add tunnel matching given tunnel parameters
1513  *     %SIOCCHGTUNNEL: change tunnel parameters to those given
1514  *     %SIOCDELTUNNEL: delete tunnel
1515  *
1516  *   The fallback device "ip6tnl0", created during module
1517  *   initialization, can be used for creating other tunnel devices.
1518  *
1519  * Return:
1520  *   0 on success,
1521  *   %-EFAULT if unable to copy data to or from userspace,
1522  *   %-EPERM if current process hasn't %CAP_NET_ADMIN set
1523  *   %-EINVAL if passed tunnel parameters are invalid,
1524  *   %-EEXIST if changing a tunnel's parameters would cause a conflict
1525  *   %-ENODEV if attempting to change or delete a nonexisting device
1526  **/
1527
1528 static int
1529 ip6_tnl_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
1530 {
1531         int err = 0;
1532         struct ip6_tnl_parm p;
1533         struct __ip6_tnl_parm p1;
1534         struct ip6_tnl *t = netdev_priv(dev);
1535         struct net *net = t->net;
1536         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1537
1538         memset(&p1, 0, sizeof(p1));
1539
1540         switch (cmd) {
1541         case SIOCGETTUNNEL:
1542                 if (dev == ip6n->fb_tnl_dev) {
1543                         if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
1544                                 err = -EFAULT;
1545                                 break;
1546                         }
1547                         ip6_tnl_parm_from_user(&p1, &p);
1548                         t = ip6_tnl_locate(net, &p1, 0);
1549                         if (IS_ERR(t))
1550                                 t = netdev_priv(dev);
1551                 } else {
1552                         memset(&p, 0, sizeof(p));
1553                 }
1554                 ip6_tnl_parm_to_user(&p, &t->parms);
1555                 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) {
1556                         err = -EFAULT;
1557                 }
1558                 break;
1559         case SIOCADDTUNNEL:
1560         case SIOCCHGTUNNEL:
1561                 err = -EPERM;
1562                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1563                         break;
1564                 err = -EFAULT;
1565                 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
1566                         break;
1567                 err = -EINVAL;
1568                 if (p.proto != IPPROTO_IPV6 && p.proto != IPPROTO_IPIP &&
1569                     p.proto != 0)
1570                         break;
1571                 ip6_tnl_parm_from_user(&p1, &p);
1572                 t = ip6_tnl_locate(net, &p1, cmd == SIOCADDTUNNEL);
1573                 if (cmd == SIOCCHGTUNNEL) {
1574                         if (!IS_ERR(t)) {
1575                                 if (t->dev != dev) {
1576                                         err = -EEXIST;
1577                                         break;
1578                                 }
1579                         } else
1580                                 t = netdev_priv(dev);
1581                         if (dev == ip6n->fb_tnl_dev)
1582                                 err = ip6_tnl0_update(t, &p1);
1583                         else
1584                                 err = ip6_tnl_update(t, &p1);
1585                 }
1586                 if (!IS_ERR(t)) {
1587                         err = 0;
1588                         ip6_tnl_parm_to_user(&p, &t->parms);
1589                         if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
1590                                 err = -EFAULT;
1591
1592                 } else {
1593                         err = PTR_ERR(t);
1594                 }
1595                 break;
1596         case SIOCDELTUNNEL:
1597                 err = -EPERM;
1598                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1599                         break;
1600
1601                 if (dev == ip6n->fb_tnl_dev) {
1602                         err = -EFAULT;
1603                         if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
1604                                 break;
1605                         err = -ENOENT;
1606                         ip6_tnl_parm_from_user(&p1, &p);
1607                         t = ip6_tnl_locate(net, &p1, 0);
1608                         if (IS_ERR(t))
1609                                 break;
1610                         err = -EPERM;
1611                         if (t->dev == ip6n->fb_tnl_dev)
1612                                 break;
1613                         dev = t->dev;
1614                 }
1615                 err = 0;
1616                 unregister_netdevice(dev);
1617                 break;
1618         default:
1619                 err = -EINVAL;
1620         }
1621         return err;
1622 }
1623
1624 /**
1625  * ip6_tnl_change_mtu - change mtu manually for tunnel device
1626  *   @dev: virtual device associated with tunnel
1627  *   @new_mtu: the new mtu
1628  *
1629  * Return:
1630  *   0 on success,
1631  *   %-EINVAL if mtu too small
1632  **/
1633
1634 int ip6_tnl_change_mtu(struct net_device *dev, int new_mtu)
1635 {
1636         struct ip6_tnl *tnl = netdev_priv(dev);
1637
1638         if (tnl->parms.proto == IPPROTO_IPIP) {
1639                 if (new_mtu < 68)
1640                         return -EINVAL;
1641         } else {
1642                 if (new_mtu < IPV6_MIN_MTU)
1643                         return -EINVAL;
1644         }
1645         if (new_mtu > 0xFFF8 - dev->hard_header_len)
1646                 return -EINVAL;
1647         dev->mtu = new_mtu;
1648         return 0;
1649 }
1650 EXPORT_SYMBOL(ip6_tnl_change_mtu);
1651
1652 int ip6_tnl_get_iflink(const struct net_device *dev)
1653 {
1654         struct ip6_tnl *t = netdev_priv(dev);
1655
1656         return t->parms.link;
1657 }
1658 EXPORT_SYMBOL(ip6_tnl_get_iflink);
1659
1660 int ip6_tnl_encap_add_ops(const struct ip6_tnl_encap_ops *ops,
1661                           unsigned int num)
1662 {
1663         if (num >= MAX_IPTUN_ENCAP_OPS)
1664                 return -ERANGE;
1665
1666         return !cmpxchg((const struct ip6_tnl_encap_ops **)
1667                         &ip6tun_encaps[num],
1668                         NULL, ops) ? 0 : -1;
1669 }
1670 EXPORT_SYMBOL(ip6_tnl_encap_add_ops);
1671
1672 int ip6_tnl_encap_del_ops(const struct ip6_tnl_encap_ops *ops,
1673                           unsigned int num)
1674 {
1675         int ret;
1676
1677         if (num >= MAX_IPTUN_ENCAP_OPS)
1678                 return -ERANGE;
1679
1680         ret = (cmpxchg((const struct ip6_tnl_encap_ops **)
1681                        &ip6tun_encaps[num],
1682                        ops, NULL) == ops) ? 0 : -1;
1683
1684         synchronize_net();
1685
1686         return ret;
1687 }
1688 EXPORT_SYMBOL(ip6_tnl_encap_del_ops);
1689
1690 int ip6_tnl_encap_setup(struct ip6_tnl *t,
1691                         struct ip_tunnel_encap *ipencap)
1692 {
1693         int hlen;
1694
1695         memset(&t->encap, 0, sizeof(t->encap));
1696
1697         hlen = ip6_encap_hlen(ipencap);
1698         if (hlen < 0)
1699                 return hlen;
1700
1701         t->encap.type = ipencap->type;
1702         t->encap.sport = ipencap->sport;
1703         t->encap.dport = ipencap->dport;
1704         t->encap.flags = ipencap->flags;
1705
1706         t->encap_hlen = hlen;
1707         t->hlen = t->encap_hlen + t->tun_hlen;
1708
1709         return 0;
1710 }
1711 EXPORT_SYMBOL_GPL(ip6_tnl_encap_setup);
1712
1713 static const struct net_device_ops ip6_tnl_netdev_ops = {
1714         .ndo_init       = ip6_tnl_dev_init,
1715         .ndo_uninit     = ip6_tnl_dev_uninit,
1716         .ndo_start_xmit = ip6_tnl_start_xmit,
1717         .ndo_do_ioctl   = ip6_tnl_ioctl,
1718         .ndo_change_mtu = ip6_tnl_change_mtu,
1719         .ndo_get_stats  = ip6_get_stats,
1720         .ndo_get_iflink = ip6_tnl_get_iflink,
1721 };
1722
1723 #define IPXIPX_FEATURES (NETIF_F_SG |           \
1724                          NETIF_F_FRAGLIST |     \
1725                          NETIF_F_HIGHDMA |      \
1726                          NETIF_F_GSO_SOFTWARE | \
1727                          NETIF_F_HW_CSUM)
1728
1729 /**
1730  * ip6_tnl_dev_setup - setup virtual tunnel device
1731  *   @dev: virtual device associated with tunnel
1732  *
1733  * Description:
1734  *   Initialize function pointers and device parameters
1735  **/
1736
1737 static void ip6_tnl_dev_setup(struct net_device *dev)
1738 {
1739         dev->netdev_ops = &ip6_tnl_netdev_ops;
1740         dev->destructor = ip6_dev_free;
1741
1742         dev->type = ARPHRD_TUNNEL6;
1743         dev->flags |= IFF_NOARP;
1744         dev->addr_len = sizeof(struct in6_addr);
1745         dev->features |= NETIF_F_LLTX;
1746         netif_keep_dst(dev);
1747
1748         dev->features           |= IPXIPX_FEATURES;
1749         dev->hw_features        |= IPXIPX_FEATURES;
1750
1751         /* This perm addr will be used as interface identifier by IPv6 */
1752         dev->addr_assign_type = NET_ADDR_RANDOM;
1753         eth_random_addr(dev->perm_addr);
1754 }
1755
1756
1757 /**
1758  * ip6_tnl_dev_init_gen - general initializer for all tunnel devices
1759  *   @dev: virtual device associated with tunnel
1760  **/
1761
1762 static inline int
1763 ip6_tnl_dev_init_gen(struct net_device *dev)
1764 {
1765         struct ip6_tnl *t = netdev_priv(dev);
1766         int ret;
1767         int t_hlen;
1768
1769         t->dev = dev;
1770         t->net = dev_net(dev);
1771         dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1772         if (!dev->tstats)
1773                 return -ENOMEM;
1774
1775         ret = dst_cache_init(&t->dst_cache, GFP_KERNEL);
1776         if (ret)
1777                 goto free_stats;
1778
1779         ret = gro_cells_init(&t->gro_cells, dev);
1780         if (ret)
1781                 goto destroy_dst;
1782
1783         t->tun_hlen = 0;
1784         t->hlen = t->encap_hlen + t->tun_hlen;
1785         t_hlen = t->hlen + sizeof(struct ipv6hdr);
1786
1787         dev->type = ARPHRD_TUNNEL6;
1788         dev->hard_header_len = LL_MAX_HEADER + t_hlen;
1789         dev->mtu = ETH_DATA_LEN - t_hlen;
1790         if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1791                 dev->mtu -= 8;
1792
1793         return 0;
1794
1795 destroy_dst:
1796         dst_cache_destroy(&t->dst_cache);
1797 free_stats:
1798         free_percpu(dev->tstats);
1799         dev->tstats = NULL;
1800
1801         return ret;
1802 }
1803
1804 /**
1805  * ip6_tnl_dev_init - initializer for all non fallback tunnel devices
1806  *   @dev: virtual device associated with tunnel
1807  **/
1808
1809 static int ip6_tnl_dev_init(struct net_device *dev)
1810 {
1811         struct ip6_tnl *t = netdev_priv(dev);
1812         int err = ip6_tnl_dev_init_gen(dev);
1813
1814         if (err)
1815                 return err;
1816         ip6_tnl_link_config(t);
1817         if (t->parms.collect_md) {
1818                 dev->features |= NETIF_F_NETNS_LOCAL;
1819                 netif_keep_dst(dev);
1820         }
1821         return 0;
1822 }
1823
1824 /**
1825  * ip6_fb_tnl_dev_init - initializer for fallback tunnel device
1826  *   @dev: fallback device
1827  *
1828  * Return: 0
1829  **/
1830
1831 static int __net_init ip6_fb_tnl_dev_init(struct net_device *dev)
1832 {
1833         struct ip6_tnl *t = netdev_priv(dev);
1834         struct net *net = dev_net(dev);
1835         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1836
1837         t->parms.proto = IPPROTO_IPV6;
1838         dev_hold(dev);
1839
1840         rcu_assign_pointer(ip6n->tnls_wc[0], t);
1841         return 0;
1842 }
1843
1844 static int ip6_tnl_validate(struct nlattr *tb[], struct nlattr *data[])
1845 {
1846         u8 proto;
1847
1848         if (!data || !data[IFLA_IPTUN_PROTO])
1849                 return 0;
1850
1851         proto = nla_get_u8(data[IFLA_IPTUN_PROTO]);
1852         if (proto != IPPROTO_IPV6 &&
1853             proto != IPPROTO_IPIP &&
1854             proto != 0)
1855                 return -EINVAL;
1856
1857         return 0;
1858 }
1859
1860 static void ip6_tnl_netlink_parms(struct nlattr *data[],
1861                                   struct __ip6_tnl_parm *parms)
1862 {
1863         memset(parms, 0, sizeof(*parms));
1864
1865         if (!data)
1866                 return;
1867
1868         if (data[IFLA_IPTUN_LINK])
1869                 parms->link = nla_get_u32(data[IFLA_IPTUN_LINK]);
1870
1871         if (data[IFLA_IPTUN_LOCAL])
1872                 parms->laddr = nla_get_in6_addr(data[IFLA_IPTUN_LOCAL]);
1873
1874         if (data[IFLA_IPTUN_REMOTE])
1875                 parms->raddr = nla_get_in6_addr(data[IFLA_IPTUN_REMOTE]);
1876
1877         if (data[IFLA_IPTUN_TTL])
1878                 parms->hop_limit = nla_get_u8(data[IFLA_IPTUN_TTL]);
1879
1880         if (data[IFLA_IPTUN_ENCAP_LIMIT])
1881                 parms->encap_limit = nla_get_u8(data[IFLA_IPTUN_ENCAP_LIMIT]);
1882
1883         if (data[IFLA_IPTUN_FLOWINFO])
1884                 parms->flowinfo = nla_get_be32(data[IFLA_IPTUN_FLOWINFO]);
1885
1886         if (data[IFLA_IPTUN_FLAGS])
1887                 parms->flags = nla_get_u32(data[IFLA_IPTUN_FLAGS]);
1888
1889         if (data[IFLA_IPTUN_PROTO])
1890                 parms->proto = nla_get_u8(data[IFLA_IPTUN_PROTO]);
1891
1892         if (data[IFLA_IPTUN_COLLECT_METADATA])
1893                 parms->collect_md = true;
1894 }
1895
1896 static bool ip6_tnl_netlink_encap_parms(struct nlattr *data[],
1897                                         struct ip_tunnel_encap *ipencap)
1898 {
1899         bool ret = false;
1900
1901         memset(ipencap, 0, sizeof(*ipencap));
1902
1903         if (!data)
1904                 return ret;
1905
1906         if (data[IFLA_IPTUN_ENCAP_TYPE]) {
1907                 ret = true;
1908                 ipencap->type = nla_get_u16(data[IFLA_IPTUN_ENCAP_TYPE]);
1909         }
1910
1911         if (data[IFLA_IPTUN_ENCAP_FLAGS]) {
1912                 ret = true;
1913                 ipencap->flags = nla_get_u16(data[IFLA_IPTUN_ENCAP_FLAGS]);
1914         }
1915
1916         if (data[IFLA_IPTUN_ENCAP_SPORT]) {
1917                 ret = true;
1918                 ipencap->sport = nla_get_be16(data[IFLA_IPTUN_ENCAP_SPORT]);
1919         }
1920
1921         if (data[IFLA_IPTUN_ENCAP_DPORT]) {
1922                 ret = true;
1923                 ipencap->dport = nla_get_be16(data[IFLA_IPTUN_ENCAP_DPORT]);
1924         }
1925
1926         return ret;
1927 }
1928
1929 static int ip6_tnl_newlink(struct net *src_net, struct net_device *dev,
1930                            struct nlattr *tb[], struct nlattr *data[])
1931 {
1932         struct net *net = dev_net(dev);
1933         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1934         struct ip6_tnl *nt, *t;
1935         struct ip_tunnel_encap ipencap;
1936
1937         nt = netdev_priv(dev);
1938
1939         if (ip6_tnl_netlink_encap_parms(data, &ipencap)) {
1940                 int err = ip6_tnl_encap_setup(nt, &ipencap);
1941
1942                 if (err < 0)
1943                         return err;
1944         }
1945
1946         ip6_tnl_netlink_parms(data, &nt->parms);
1947
1948         if (nt->parms.collect_md) {
1949                 if (rtnl_dereference(ip6n->collect_md_tun))
1950                         return -EEXIST;
1951         } else {
1952                 t = ip6_tnl_locate(net, &nt->parms, 0);
1953                 if (!IS_ERR(t))
1954                         return -EEXIST;
1955         }
1956
1957         return ip6_tnl_create2(dev);
1958 }
1959
1960 static int ip6_tnl_changelink(struct net_device *dev, struct nlattr *tb[],
1961                               struct nlattr *data[])
1962 {
1963         struct ip6_tnl *t = netdev_priv(dev);
1964         struct __ip6_tnl_parm p;
1965         struct net *net = t->net;
1966         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1967         struct ip_tunnel_encap ipencap;
1968
1969         if (dev == ip6n->fb_tnl_dev)
1970                 return -EINVAL;
1971
1972         if (ip6_tnl_netlink_encap_parms(data, &ipencap)) {
1973                 int err = ip6_tnl_encap_setup(t, &ipencap);
1974
1975                 if (err < 0)
1976                         return err;
1977         }
1978         ip6_tnl_netlink_parms(data, &p);
1979         if (p.collect_md)
1980                 return -EINVAL;
1981
1982         t = ip6_tnl_locate(net, &p, 0);
1983         if (!IS_ERR(t)) {
1984                 if (t->dev != dev)
1985                         return -EEXIST;
1986         } else
1987                 t = netdev_priv(dev);
1988
1989         return ip6_tnl_update(t, &p);
1990 }
1991
1992 static void ip6_tnl_dellink(struct net_device *dev, struct list_head *head)
1993 {
1994         struct net *net = dev_net(dev);
1995         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1996
1997         if (dev != ip6n->fb_tnl_dev)
1998                 unregister_netdevice_queue(dev, head);
1999 }
2000
2001 static size_t ip6_tnl_get_size(const struct net_device *dev)
2002 {
2003         return
2004                 /* IFLA_IPTUN_LINK */
2005                 nla_total_size(4) +
2006                 /* IFLA_IPTUN_LOCAL */
2007                 nla_total_size(sizeof(struct in6_addr)) +
2008                 /* IFLA_IPTUN_REMOTE */
2009                 nla_total_size(sizeof(struct in6_addr)) +
2010                 /* IFLA_IPTUN_TTL */
2011                 nla_total_size(1) +
2012                 /* IFLA_IPTUN_ENCAP_LIMIT */
2013                 nla_total_size(1) +
2014                 /* IFLA_IPTUN_FLOWINFO */
2015                 nla_total_size(4) +
2016                 /* IFLA_IPTUN_FLAGS */
2017                 nla_total_size(4) +
2018                 /* IFLA_IPTUN_PROTO */
2019                 nla_total_size(1) +
2020                 /* IFLA_IPTUN_ENCAP_TYPE */
2021                 nla_total_size(2) +
2022                 /* IFLA_IPTUN_ENCAP_FLAGS */
2023                 nla_total_size(2) +
2024                 /* IFLA_IPTUN_ENCAP_SPORT */
2025                 nla_total_size(2) +
2026                 /* IFLA_IPTUN_ENCAP_DPORT */
2027                 nla_total_size(2) +
2028                 /* IFLA_IPTUN_COLLECT_METADATA */
2029                 nla_total_size(0) +
2030                 0;
2031 }
2032
2033 static int ip6_tnl_fill_info(struct sk_buff *skb, const struct net_device *dev)
2034 {
2035         struct ip6_tnl *tunnel = netdev_priv(dev);
2036         struct __ip6_tnl_parm *parm = &tunnel->parms;
2037
2038         if (nla_put_u32(skb, IFLA_IPTUN_LINK, parm->link) ||
2039             nla_put_in6_addr(skb, IFLA_IPTUN_LOCAL, &parm->laddr) ||
2040             nla_put_in6_addr(skb, IFLA_IPTUN_REMOTE, &parm->raddr) ||
2041             nla_put_u8(skb, IFLA_IPTUN_TTL, parm->hop_limit) ||
2042             nla_put_u8(skb, IFLA_IPTUN_ENCAP_LIMIT, parm->encap_limit) ||
2043             nla_put_be32(skb, IFLA_IPTUN_FLOWINFO, parm->flowinfo) ||
2044             nla_put_u32(skb, IFLA_IPTUN_FLAGS, parm->flags) ||
2045             nla_put_u8(skb, IFLA_IPTUN_PROTO, parm->proto))
2046                 goto nla_put_failure;
2047
2048         if (nla_put_u16(skb, IFLA_IPTUN_ENCAP_TYPE, tunnel->encap.type) ||
2049             nla_put_be16(skb, IFLA_IPTUN_ENCAP_SPORT, tunnel->encap.sport) ||
2050             nla_put_be16(skb, IFLA_IPTUN_ENCAP_DPORT, tunnel->encap.dport) ||
2051             nla_put_u16(skb, IFLA_IPTUN_ENCAP_FLAGS, tunnel->encap.flags))
2052                 goto nla_put_failure;
2053
2054         if (parm->collect_md)
2055                 if (nla_put_flag(skb, IFLA_IPTUN_COLLECT_METADATA))
2056                         goto nla_put_failure;
2057         return 0;
2058
2059 nla_put_failure:
2060         return -EMSGSIZE;
2061 }
2062
2063 struct net *ip6_tnl_get_link_net(const struct net_device *dev)
2064 {
2065         struct ip6_tnl *tunnel = netdev_priv(dev);
2066
2067         return tunnel->net;
2068 }
2069 EXPORT_SYMBOL(ip6_tnl_get_link_net);
2070
2071 static const struct nla_policy ip6_tnl_policy[IFLA_IPTUN_MAX + 1] = {
2072         [IFLA_IPTUN_LINK]               = { .type = NLA_U32 },
2073         [IFLA_IPTUN_LOCAL]              = { .len = sizeof(struct in6_addr) },
2074         [IFLA_IPTUN_REMOTE]             = { .len = sizeof(struct in6_addr) },
2075         [IFLA_IPTUN_TTL]                = { .type = NLA_U8 },
2076         [IFLA_IPTUN_ENCAP_LIMIT]        = { .type = NLA_U8 },
2077         [IFLA_IPTUN_FLOWINFO]           = { .type = NLA_U32 },
2078         [IFLA_IPTUN_FLAGS]              = { .type = NLA_U32 },
2079         [IFLA_IPTUN_PROTO]              = { .type = NLA_U8 },
2080         [IFLA_IPTUN_ENCAP_TYPE]         = { .type = NLA_U16 },
2081         [IFLA_IPTUN_ENCAP_FLAGS]        = { .type = NLA_U16 },
2082         [IFLA_IPTUN_ENCAP_SPORT]        = { .type = NLA_U16 },
2083         [IFLA_IPTUN_ENCAP_DPORT]        = { .type = NLA_U16 },
2084         [IFLA_IPTUN_COLLECT_METADATA]   = { .type = NLA_FLAG },
2085 };
2086
2087 static struct rtnl_link_ops ip6_link_ops __read_mostly = {
2088         .kind           = "ip6tnl",
2089         .maxtype        = IFLA_IPTUN_MAX,
2090         .policy         = ip6_tnl_policy,
2091         .priv_size      = sizeof(struct ip6_tnl),
2092         .setup          = ip6_tnl_dev_setup,
2093         .validate       = ip6_tnl_validate,
2094         .newlink        = ip6_tnl_newlink,
2095         .changelink     = ip6_tnl_changelink,
2096         .dellink        = ip6_tnl_dellink,
2097         .get_size       = ip6_tnl_get_size,
2098         .fill_info      = ip6_tnl_fill_info,
2099         .get_link_net   = ip6_tnl_get_link_net,
2100 };
2101
2102 static struct xfrm6_tunnel ip4ip6_handler __read_mostly = {
2103         .handler        = ip4ip6_rcv,
2104         .err_handler    = ip4ip6_err,
2105         .priority       =       1,
2106 };
2107
2108 static struct xfrm6_tunnel ip6ip6_handler __read_mostly = {
2109         .handler        = ip6ip6_rcv,
2110         .err_handler    = ip6ip6_err,
2111         .priority       =       1,
2112 };
2113
2114 static void __net_exit ip6_tnl_destroy_tunnels(struct net *net)
2115 {
2116         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
2117         struct net_device *dev, *aux;
2118         int h;
2119         struct ip6_tnl *t;
2120         LIST_HEAD(list);
2121
2122         for_each_netdev_safe(net, dev, aux)
2123                 if (dev->rtnl_link_ops == &ip6_link_ops)
2124                         unregister_netdevice_queue(dev, &list);
2125
2126         for (h = 0; h < IP6_TUNNEL_HASH_SIZE; h++) {
2127                 t = rtnl_dereference(ip6n->tnls_r_l[h]);
2128                 while (t) {
2129                         /* If dev is in the same netns, it has already
2130                          * been added to the list by the previous loop.
2131                          */
2132                         if (!net_eq(dev_net(t->dev), net))
2133                                 unregister_netdevice_queue(t->dev, &list);
2134                         t = rtnl_dereference(t->next);
2135                 }
2136         }
2137
2138         unregister_netdevice_many(&list);
2139 }
2140
2141 static int __net_init ip6_tnl_init_net(struct net *net)
2142 {
2143         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
2144         struct ip6_tnl *t = NULL;
2145         int err;
2146
2147         ip6n->tnls[0] = ip6n->tnls_wc;
2148         ip6n->tnls[1] = ip6n->tnls_r_l;
2149
2150         err = -ENOMEM;
2151         ip6n->fb_tnl_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6tnl0",
2152                                         NET_NAME_UNKNOWN, ip6_tnl_dev_setup);
2153
2154         if (!ip6n->fb_tnl_dev)
2155                 goto err_alloc_dev;
2156         dev_net_set(ip6n->fb_tnl_dev, net);
2157         ip6n->fb_tnl_dev->rtnl_link_ops = &ip6_link_ops;
2158         /* FB netdevice is special: we have one, and only one per netns.
2159          * Allowing to move it to another netns is clearly unsafe.
2160          */
2161         ip6n->fb_tnl_dev->features |= NETIF_F_NETNS_LOCAL;
2162
2163         err = ip6_fb_tnl_dev_init(ip6n->fb_tnl_dev);
2164         if (err < 0)
2165                 goto err_register;
2166
2167         err = register_netdev(ip6n->fb_tnl_dev);
2168         if (err < 0)
2169                 goto err_register;
2170
2171         t = netdev_priv(ip6n->fb_tnl_dev);
2172
2173         strcpy(t->parms.name, ip6n->fb_tnl_dev->name);
2174         return 0;
2175
2176 err_register:
2177         ip6_dev_free(ip6n->fb_tnl_dev);
2178 err_alloc_dev:
2179         return err;
2180 }
2181
2182 static void __net_exit ip6_tnl_exit_net(struct net *net)
2183 {
2184         rtnl_lock();
2185         ip6_tnl_destroy_tunnels(net);
2186         rtnl_unlock();
2187 }
2188
2189 static struct pernet_operations ip6_tnl_net_ops = {
2190         .init = ip6_tnl_init_net,
2191         .exit = ip6_tnl_exit_net,
2192         .id   = &ip6_tnl_net_id,
2193         .size = sizeof(struct ip6_tnl_net),
2194 };
2195
2196 /**
2197  * ip6_tunnel_init - register protocol and reserve needed resources
2198  *
2199  * Return: 0 on success
2200  **/
2201
2202 static int __init ip6_tunnel_init(void)
2203 {
2204         int  err;
2205
2206         err = register_pernet_device(&ip6_tnl_net_ops);
2207         if (err < 0)
2208                 goto out_pernet;
2209
2210         err = xfrm6_tunnel_register(&ip4ip6_handler, AF_INET);
2211         if (err < 0) {
2212                 pr_err("%s: can't register ip4ip6\n", __func__);
2213                 goto out_ip4ip6;
2214         }
2215
2216         err = xfrm6_tunnel_register(&ip6ip6_handler, AF_INET6);
2217         if (err < 0) {
2218                 pr_err("%s: can't register ip6ip6\n", __func__);
2219                 goto out_ip6ip6;
2220         }
2221         err = rtnl_link_register(&ip6_link_ops);
2222         if (err < 0)
2223                 goto rtnl_link_failed;
2224
2225         return 0;
2226
2227 rtnl_link_failed:
2228         xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6);
2229 out_ip6ip6:
2230         xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET);
2231 out_ip4ip6:
2232         unregister_pernet_device(&ip6_tnl_net_ops);
2233 out_pernet:
2234         return err;
2235 }
2236
2237 /**
2238  * ip6_tunnel_cleanup - free resources and unregister protocol
2239  **/
2240
2241 static void __exit ip6_tunnel_cleanup(void)
2242 {
2243         rtnl_link_unregister(&ip6_link_ops);
2244         if (xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET))
2245                 pr_info("%s: can't deregister ip4ip6\n", __func__);
2246
2247         if (xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6))
2248                 pr_info("%s: can't deregister ip6ip6\n", __func__);
2249
2250         unregister_pernet_device(&ip6_tnl_net_ops);
2251 }
2252
2253 module_init(ip6_tunnel_init);
2254 module_exit(ip6_tunnel_cleanup);