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