net/ipv6/ip6_gre.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *      GRE over IPv6 protocol decoder.
   4  *
   5  *      Authors: Dmitry Kozlov (xeb@mail.ru)
   6  */
   7
   8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
   9
  10 #include <linux/capability.h>
  11 #include <linux/module.h>
  12 #include <linux/types.h>
  13 #include <linux/kernel.h>
  14 #include <linux/slab.h>
  15 #include <linux/uaccess.h>
  16 #include <linux/skbuff.h>
  17 #include <linux/netdevice.h>
  18 #include <linux/in.h>
  19 #include <linux/tcp.h>
  20 #include <linux/udp.h>
  21 #include <linux/if_arp.h>
  22 #include <linux/init.h>
  23 #include <linux/in6.h>
  24 #include <linux/inetdevice.h>
  25 #include <linux/igmp.h>
  26 #include <linux/netfilter_ipv4.h>
  27 #include <linux/etherdevice.h>
  28 #include <linux/if_ether.h>
  29 #include <linux/hash.h>
  30 #include <linux/if_tunnel.h>
  31 #include <linux/ip6_tunnel.h>
  32
  33 #include <net/sock.h>
  34 #include <net/ip.h>
  35 #include <net/ip_tunnels.h>
  36 #include <net/icmp.h>
  37 #include <net/protocol.h>
  38 #include <net/addrconf.h>
  39 #include <net/arp.h>
  40 #include <net/checksum.h>
  41 #include <net/dsfield.h>
  42 #include <net/inet_ecn.h>
  43 #include <net/xfrm.h>
  44 #include <net/net_namespace.h>
  45 #include <net/netns/generic.h>
  46 #include <net/rtnetlink.h>
  47
  48 #include <net/ipv6.h>
  49 #include <net/ip6_fib.h>
  50 #include <net/ip6_route.h>
  51 #include <net/ip6_tunnel.h>
  52 #include <net/gre.h>
  53 #include <net/erspan.h>
  54 #include <net/dst_metadata.h>
  55
  56
  57 static bool log_ecn_error = true;
  58 module_param(log_ecn_error, bool, 0644);
  59 MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");
  60
  61 #define IP6_GRE_HASH_SIZE_SHIFT  5
  62 #define IP6_GRE_HASH_SIZE (1 << IP6_GRE_HASH_SIZE_SHIFT)
  63
  64 static unsigned int ip6gre_net_id __read_mostly;
  65 struct ip6gre_net {
  66         struct ip6_tnl __rcu *tunnels[4][IP6_GRE_HASH_SIZE];
  67
  68         struct ip6_tnl __rcu *collect_md_tun;
  69         struct ip6_tnl __rcu *collect_md_tun_erspan;
  70         struct net_device *fb_tunnel_dev;
  71 };
  72
  73 static struct rtnl_link_ops ip6gre_link_ops __read_mostly;
  74 static struct rtnl_link_ops ip6gre_tap_ops __read_mostly;
  75 static struct rtnl_link_ops ip6erspan_tap_ops __read_mostly;
  76 static int ip6gre_tunnel_init(struct net_device *dev);
  77 static void ip6gre_tunnel_setup(struct net_device *dev);
  78 static void ip6gre_tunnel_link(struct ip6gre_net *ign, struct ip6_tnl *t);
  79 static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu);
  80 static void ip6erspan_tnl_link_config(struct ip6_tnl *t, int set_mtu);
  81
  82 /* Tunnel hash table */
  83
  84 /*
  85    4 hash tables:
  86
  87    3: (remote,local)
  88    2: (remote,*)
  89    1: (*,local)
  90    0: (*,*)
  91
  92    We require exact key match i.e. if a key is present in packet
  93    it will match only tunnel with the same key; if it is not present,
  94    it will match only keyless tunnel.
  95
  96    All keysless packets, if not matched configured keyless tunnels
  97    will match fallback tunnel.
  98  */
  99
 100 #define HASH_KEY(key) (((__force u32)key^((__force u32)key>>4))&(IP6_GRE_HASH_SIZE - 1))
 101 static u32 HASH_ADDR(const struct in6_addr *addr)
 102 {
 103         u32 hash = ipv6_addr_hash(addr);
 104
 105         return hash_32(hash, IP6_GRE_HASH_SIZE_SHIFT);
 106 }
 107
 108 #define tunnels_r_l     tunnels[3]
 109 #define tunnels_r       tunnels[2]
 110 #define tunnels_l       tunnels[1]
 111 #define tunnels_wc      tunnels[0]
 112
 113 /* Given src, dst and key, find appropriate for input tunnel. */
 114
 115 static struct ip6_tnl *ip6gre_tunnel_lookup(struct net_device *dev,
 116                 const struct in6_addr *remote, const struct in6_addr *local,
 117                 __be32 key, __be16 gre_proto)
 118 {
 119         struct net *net = dev_net(dev);
 120         int link = dev->ifindex;
 121         unsigned int h0 = HASH_ADDR(remote);
 122         unsigned int h1 = HASH_KEY(key);
 123         struct ip6_tnl *t, *cand = NULL;
 124         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
 125         int dev_type = (gre_proto == htons(ETH_P_TEB) ||
 126                         gre_proto == htons(ETH_P_ERSPAN) ||
 127                         gre_proto == htons(ETH_P_ERSPAN2)) ?
 128                        ARPHRD_ETHER : ARPHRD_IP6GRE;
 129         int score, cand_score = 4;
 130         struct net_device *ndev;
 131
 132         for_each_ip_tunnel_rcu(t, ign->tunnels_r_l[h0 ^ h1]) {
 133                 if (!ipv6_addr_equal(local, &t->parms.laddr) ||
 134                     !ipv6_addr_equal(remote, &t->parms.raddr) ||
 135                     key != t->parms.i_key ||
 136                     !(t->dev->flags & IFF_UP))
 137                         continue;
 138
 139                 if (t->dev->type != ARPHRD_IP6GRE &&
 140                     t->dev->type != dev_type)
 141                         continue;
 142
 143                 score = 0;
 144                 if (t->parms.link != link)
 145                         score |= 1;
 146                 if (t->dev->type != dev_type)
 147                         score |= 2;
 148                 if (score == 0)
 149                         return t;
 150
 151                 if (score < cand_score) {
 152                         cand = t;
 153                         cand_score = score;
 154                 }
 155         }
 156
 157         for_each_ip_tunnel_rcu(t, ign->tunnels_r[h0 ^ h1]) {
 158                 if (!ipv6_addr_equal(remote, &t->parms.raddr) ||
 159                     key != t->parms.i_key ||
 160                     !(t->dev->flags & IFF_UP))
 161                         continue;
 162
 163                 if (t->dev->type != ARPHRD_IP6GRE &&
 164                     t->dev->type != dev_type)
 165                         continue;
 166
 167                 score = 0;
 168                 if (t->parms.link != link)
 169                         score |= 1;
 170                 if (t->dev->type != dev_type)
 171                         score |= 2;
 172                 if (score == 0)
 173                         return t;
 174
 175                 if (score < cand_score) {
 176                         cand = t;
 177                         cand_score = score;
 178                 }
 179         }
 180
 181         for_each_ip_tunnel_rcu(t, ign->tunnels_l[h1]) {
 182                 if ((!ipv6_addr_equal(local, &t->parms.laddr) &&
 183                           (!ipv6_addr_equal(local, &t->parms.raddr) ||
 184                                  !ipv6_addr_is_multicast(local))) ||
 185                     key != t->parms.i_key ||
 186                     !(t->dev->flags & IFF_UP))
 187                         continue;
 188
 189                 if (t->dev->type != ARPHRD_IP6GRE &&
 190                     t->dev->type != dev_type)
 191                         continue;
 192
 193                 score = 0;
 194                 if (t->parms.link != link)
 195                         score |= 1;
 196                 if (t->dev->type != dev_type)
 197                         score |= 2;
 198                 if (score == 0)
 199                         return t;
 200
 201                 if (score < cand_score) {
 202                         cand = t;
 203                         cand_score = score;
 204                 }
 205         }
 206
 207         for_each_ip_tunnel_rcu(t, ign->tunnels_wc[h1]) {
 208                 if (t->parms.i_key != key ||
 209                     !(t->dev->flags & IFF_UP))
 210                         continue;
 211
 212                 if (t->dev->type != ARPHRD_IP6GRE &&
 213                     t->dev->type != dev_type)
 214                         continue;
 215
 216                 score = 0;
 217                 if (t->parms.link != link)
 218                         score |= 1;
 219                 if (t->dev->type != dev_type)
 220                         score |= 2;
 221                 if (score == 0)
 222                         return t;
 223
 224                 if (score < cand_score) {
 225                         cand = t;
 226                         cand_score = score;
 227                 }
 228         }
 229
 230         if (cand)
 231                 return cand;
 232
 233         if (gre_proto == htons(ETH_P_ERSPAN) ||
 234             gre_proto == htons(ETH_P_ERSPAN2))
 235                 t = rcu_dereference(ign->collect_md_tun_erspan);
 236         else
 237                 t = rcu_dereference(ign->collect_md_tun);
 238
 239         if (t && t->dev->flags & IFF_UP)
 240                 return t;
 241
 242         ndev = READ_ONCE(ign->fb_tunnel_dev);
 243         if (ndev && ndev->flags & IFF_UP)
 244                 return netdev_priv(ndev);
 245
 246         return NULL;
 247 }
 248
 249 static struct ip6_tnl __rcu **__ip6gre_bucket(struct ip6gre_net *ign,
 250                 const struct __ip6_tnl_parm *p)
 251 {
 252         const struct in6_addr *remote = &p->raddr;
 253         const struct in6_addr *local = &p->laddr;
 254         unsigned int h = HASH_KEY(p->i_key);
 255         int prio = 0;
 256
 257         if (!ipv6_addr_any(local))
 258                 prio |= 1;
 259         if (!ipv6_addr_any(remote) && !ipv6_addr_is_multicast(remote)) {
 260                 prio |= 2;
 261                 h ^= HASH_ADDR(remote);
 262         }
 263
 264         return &ign->tunnels[prio][h];
 265 }
 266
 267 static void ip6gre_tunnel_link_md(struct ip6gre_net *ign, struct ip6_tnl *t)
 268 {
 269         if (t->parms.collect_md)
 270                 rcu_assign_pointer(ign->collect_md_tun, t);
 271 }
 272
 273 static void ip6erspan_tunnel_link_md(struct ip6gre_net *ign, struct ip6_tnl *t)
 274 {
 275         if (t->parms.collect_md)
 276                 rcu_assign_pointer(ign->collect_md_tun_erspan, t);
 277 }
 278
 279 static void ip6gre_tunnel_unlink_md(struct ip6gre_net *ign, struct ip6_tnl *t)
 280 {
 281         if (t->parms.collect_md)
 282                 rcu_assign_pointer(ign->collect_md_tun, NULL);
 283 }
 284
 285 static void ip6erspan_tunnel_unlink_md(struct ip6gre_net *ign,
 286                                        struct ip6_tnl *t)
 287 {
 288         if (t->parms.collect_md)
 289                 rcu_assign_pointer(ign->collect_md_tun_erspan, NULL);
 290 }
 291
 292 static inline struct ip6_tnl __rcu **ip6gre_bucket(struct ip6gre_net *ign,
 293                 const struct ip6_tnl *t)
 294 {
 295         return __ip6gre_bucket(ign, &t->parms);
 296 }
 297
 298 static void ip6gre_tunnel_link(struct ip6gre_net *ign, struct ip6_tnl *t)
 299 {
 300         struct ip6_tnl __rcu **tp = ip6gre_bucket(ign, t);
 301
 302         rcu_assign_pointer(t->next, rtnl_dereference(*tp));
 303         rcu_assign_pointer(*tp, t);
 304 }
 305
 306 static void ip6gre_tunnel_unlink(struct ip6gre_net *ign, struct ip6_tnl *t)
 307 {
 308         struct ip6_tnl __rcu **tp;
 309         struct ip6_tnl *iter;
 310
 311         for (tp = ip6gre_bucket(ign, t);
 312              (iter = rtnl_dereference(*tp)) != NULL;
 313              tp = &iter->next) {
 314                 if (t == iter) {
 315                         rcu_assign_pointer(*tp, t->next);
 316                         break;
 317                 }
 318         }
 319 }
 320
 321 static struct ip6_tnl *ip6gre_tunnel_find(struct net *net,
 322                                            const struct __ip6_tnl_parm *parms,
 323                                            int type)
 324 {
 325         const struct in6_addr *remote = &parms->raddr;
 326         const struct in6_addr *local = &parms->laddr;
 327         __be32 key = parms->i_key;
 328         int link = parms->link;
 329         struct ip6_tnl *t;
 330         struct ip6_tnl __rcu **tp;
 331         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
 332
 333         for (tp = __ip6gre_bucket(ign, parms);
 334              (t = rtnl_dereference(*tp)) != NULL;
 335              tp = &t->next)
 336                 if (ipv6_addr_equal(local, &t->parms.laddr) &&
 337                     ipv6_addr_equal(remote, &t->parms.raddr) &&
 338                     key == t->parms.i_key &&
 339                     link == t->parms.link &&
 340                     type == t->dev->type)
 341                         break;
 342
 343         return t;
 344 }
 345
 346 static struct ip6_tnl *ip6gre_tunnel_locate(struct net *net,
 347                 const struct __ip6_tnl_parm *parms, int create)
 348 {
 349         struct ip6_tnl *t, *nt;
 350         struct net_device *dev;
 351         char name[IFNAMSIZ];
 352         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
 353
 354         t = ip6gre_tunnel_find(net, parms, ARPHRD_IP6GRE);
 355         if (t && create)
 356                 return NULL;
 357         if (t || !create)
 358                 return t;
 359
 360         if (parms->name[0]) {
 361                 if (!dev_valid_name(parms->name))
 362                         return NULL;
 363                 strlcpy(name, parms->name, IFNAMSIZ);
 364         } else {
 365                 strcpy(name, "ip6gre%d");
 366         }
 367         dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN,
 368                            ip6gre_tunnel_setup);
 369         if (!dev)
 370                 return NULL;
 371
 372         dev_net_set(dev, net);
 373
 374         nt = netdev_priv(dev);
 375         nt->parms = *parms;
 376         dev->rtnl_link_ops = &ip6gre_link_ops;
 377
 378         nt->dev = dev;
 379         nt->net = dev_net(dev);
 380
 381         if (register_netdevice(dev) < 0)
 382                 goto failed_free;
 383
 384         ip6gre_tnl_link_config(nt, 1);
 385
 386         /* Can use a lockless transmit, unless we generate output sequences */
 387         if (!(nt->parms.o_flags & TUNNEL_SEQ))
 388                 dev->features |= NETIF_F_LLTX;
 389
 390         ip6gre_tunnel_link(ign, nt);
 391         return nt;
 392
 393 failed_free:
 394         free_netdev(dev);
 395         return NULL;
 396 }
 397
 398 static void ip6erspan_tunnel_uninit(struct net_device *dev)
 399 {
 400         struct ip6_tnl *t = netdev_priv(dev);
 401         struct ip6gre_net *ign = net_generic(t->net, ip6gre_net_id);
 402
 403         ip6erspan_tunnel_unlink_md(ign, t);
 404         ip6gre_tunnel_unlink(ign, t);
 405         dst_cache_reset(&t->dst_cache);
 406         dev_put(dev);
 407 }
 408
 409 static void ip6gre_tunnel_uninit(struct net_device *dev)
 410 {
 411         struct ip6_tnl *t = netdev_priv(dev);
 412         struct ip6gre_net *ign = net_generic(t->net, ip6gre_net_id);
 413
 414         ip6gre_tunnel_unlink_md(ign, t);
 415         ip6gre_tunnel_unlink(ign, t);
 416         if (ign->fb_tunnel_dev == dev)
 417                 WRITE_ONCE(ign->fb_tunnel_dev, NULL);
 418         dst_cache_reset(&t->dst_cache);
 419         dev_put(dev);
 420 }
 421
 422
 423 static int ip6gre_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 424                        u8 type, u8 code, int offset, __be32 info)
 425 {
 426         struct net *net = dev_net(skb->dev);
 427         const struct ipv6hdr *ipv6h;
 428         struct tnl_ptk_info tpi;
 429         struct ip6_tnl *t;
 430
 431         if (gre_parse_header(skb, &tpi, NULL, htons(ETH_P_IPV6),
 432                              offset) < 0)
 433                 return -EINVAL;
 434
 435         ipv6h = (const struct ipv6hdr *)skb->data;
 436         t = ip6gre_tunnel_lookup(skb->dev, &ipv6h->daddr, &ipv6h->saddr,
 437                                  tpi.key, tpi.proto);
 438         if (!t)
 439                 return -ENOENT;
 440
 441         switch (type) {
 442         case ICMPV6_DEST_UNREACH:
 443                 net_dbg_ratelimited("%s: Path to destination invalid or inactive!\n",
 444                                     t->parms.name);
 445                 if (code != ICMPV6_PORT_UNREACH)
 446                         break;
 447                 return 0;
 448         case ICMPV6_TIME_EXCEED:
 449                 if (code == ICMPV6_EXC_HOPLIMIT) {
 450                         net_dbg_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n",
 451                                             t->parms.name);
 452                         break;
 453                 }
 454                 return 0;
 455         case ICMPV6_PARAMPROB: {
 456                 struct ipv6_tlv_tnl_enc_lim *tel;
 457                 __u32 teli;
 458
 459                 teli = 0;
 460                 if (code == ICMPV6_HDR_FIELD)
 461                         teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data);
 462
 463                 if (teli && teli == be32_to_cpu(info) - 2) {
 464                         tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli];
 465                         if (tel->encap_limit == 0) {
 466                                 net_dbg_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n",
 467                                                     t->parms.name);
 468                         }
 469                 } else {
 470                         net_dbg_ratelimited("%s: Recipient unable to parse tunneled packet!\n",
 471                                             t->parms.name);
 472                 }
 473                 return 0;
 474         }
 475         case ICMPV6_PKT_TOOBIG:
 476                 ip6_update_pmtu(skb, net, info, 0, 0, sock_net_uid(net, NULL));
 477                 return 0;
 478         case NDISC_REDIRECT:
 479                 ip6_redirect(skb, net, skb->dev->ifindex, 0,
 480                              sock_net_uid(net, NULL));
 481                 return 0;
 482         }
 483
 484         if (time_before(jiffies, t->err_time + IP6TUNNEL_ERR_TIMEO))
 485                 t->err_count++;
 486         else
 487                 t->err_count = 1;
 488         t->err_time = jiffies;
 489
 490         return 0;
 491 }
 492
 493 static int ip6gre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi)
 494 {
 495         const struct ipv6hdr *ipv6h;
 496         struct ip6_tnl *tunnel;
 497
 498         ipv6h = ipv6_hdr(skb);
 499         tunnel = ip6gre_tunnel_lookup(skb->dev,
 500                                       &ipv6h->saddr, &ipv6h->daddr, tpi->key,
 501                                       tpi->proto);
 502         if (tunnel) {
 503                 if (tunnel->parms.collect_md) {
 504                         struct metadata_dst *tun_dst;
 505                         __be64 tun_id;
 506                         __be16 flags;
 507
 508                         flags = tpi->flags;
 509                         tun_id = key32_to_tunnel_id(tpi->key);
 510
 511                         tun_dst = ipv6_tun_rx_dst(skb, flags, tun_id, 0);
 512                         if (!tun_dst)
 513                                 return PACKET_REJECT;
 514
 515                         ip6_tnl_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
 516                 } else {
 517                         ip6_tnl_rcv(tunnel, skb, tpi, NULL, log_ecn_error);
 518                 }
 519
 520                 return PACKET_RCVD;
 521         }
 522
 523         return PACKET_REJECT;
 524 }
 525
 526 static int ip6erspan_rcv(struct sk_buff *skb,
 527                          struct tnl_ptk_info *tpi,
 528                          int gre_hdr_len)
 529 {
 530         struct erspan_base_hdr *ershdr;
 531         const struct ipv6hdr *ipv6h;
 532         struct erspan_md2 *md2;
 533         struct ip6_tnl *tunnel;
 534         u8 ver;
 535
 536         ipv6h = ipv6_hdr(skb);
 537         ershdr = (struct erspan_base_hdr *)skb->data;
 538         ver = ershdr->ver;
 539
 540         tunnel = ip6gre_tunnel_lookup(skb->dev,
 541                                       &ipv6h->saddr, &ipv6h->daddr, tpi->key,
 542                                       tpi->proto);
 543         if (tunnel) {
 544                 int len = erspan_hdr_len(ver);
 545
 546                 if (unlikely(!pskb_may_pull(skb, len)))
 547                         return PACKET_REJECT;
 548
 549                 if (__iptunnel_pull_header(skb, len,
 550                                            htons(ETH_P_TEB),
 551                                            false, false) < 0)
 552                         return PACKET_REJECT;
 553
 554                 if (tunnel->parms.collect_md) {
 555                         struct erspan_metadata *pkt_md, *md;
 556                         struct metadata_dst *tun_dst;
 557                         struct ip_tunnel_info *info;
 558                         unsigned char *gh;
 559                         __be64 tun_id;
 560                         __be16 flags;
 561
 562                         tpi->flags |= TUNNEL_KEY;
 563                         flags = tpi->flags;
 564                         tun_id = key32_to_tunnel_id(tpi->key);
 565
 566                         tun_dst = ipv6_tun_rx_dst(skb, flags, tun_id,
 567                                                   sizeof(*md));
 568                         if (!tun_dst)
 569                                 return PACKET_REJECT;
 570
 571                         /* skb can be uncloned in __iptunnel_pull_header, so
 572                          * old pkt_md is no longer valid and we need to reset
 573                          * it
 574                          */
 575                         gh = skb_network_header(skb) +
 576                              skb_network_header_len(skb);
 577                         pkt_md = (struct erspan_metadata *)(gh + gre_hdr_len +
 578                                                             sizeof(*ershdr));
 579                         info = &tun_dst->u.tun_info;
 580                         md = ip_tunnel_info_opts(info);
 581                         md->version = ver;
 582                         md2 = &md->u.md2;
 583                         memcpy(md2, pkt_md, ver == 1 ? ERSPAN_V1_MDSIZE :
 584                                                        ERSPAN_V2_MDSIZE);
 585                         info->key.tun_flags |= TUNNEL_ERSPAN_OPT;
 586                         info->options_len = sizeof(*md);
 587
 588                         ip6_tnl_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
 589
 590                 } else {
 591                         ip6_tnl_rcv(tunnel, skb, tpi, NULL, log_ecn_error);
 592                 }
 593
 594                 return PACKET_RCVD;
 595         }
 596
 597         return PACKET_REJECT;
 598 }
 599
 600 static int gre_rcv(struct sk_buff *skb)
 601 {
 602         struct tnl_ptk_info tpi;
 603         bool csum_err = false;
 604         int hdr_len;
 605
 606         hdr_len = gre_parse_header(skb, &tpi, &csum_err, htons(ETH_P_IPV6), 0);
 607         if (hdr_len < 0)
 608                 goto drop;
 609
 610         if (iptunnel_pull_header(skb, hdr_len, tpi.proto, false))
 611                 goto drop;
 612
 613         if (unlikely(tpi.proto == htons(ETH_P_ERSPAN) ||
 614                      tpi.proto == htons(ETH_P_ERSPAN2))) {
 615                 if (ip6erspan_rcv(skb, &tpi, hdr_len) == PACKET_RCVD)
 616                         return 0;
 617                 goto out;
 618         }
 619
 620         if (ip6gre_rcv(skb, &tpi) == PACKET_RCVD)
 621                 return 0;
 622
 623 out:
 624         icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
 625 drop:
 626         kfree_skb(skb);
 627         return 0;
 628 }
 629
 630 static int gre_handle_offloads(struct sk_buff *skb, bool csum)
 631 {
 632         return iptunnel_handle_offloads(skb,
 633                                         csum ? SKB_GSO_GRE_CSUM : SKB_GSO_GRE);
 634 }
 635
 636 static void prepare_ip6gre_xmit_ipv4(struct sk_buff *skb,
 637                                      struct net_device *dev,
 638                                      struct flowi6 *fl6, __u8 *dsfield,
 639                                      int *encap_limit)
 640 {
 641         const struct iphdr *iph = ip_hdr(skb);
 642         struct ip6_tnl *t = netdev_priv(dev);
 643
 644         if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
 645                 *encap_limit = t->parms.encap_limit;
 646
 647         memcpy(fl6, &t->fl.u.ip6, sizeof(*fl6));
 648
 649         if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
 650                 *dsfield = ipv4_get_dsfield(iph);
 651         else
 652                 *dsfield = ip6_tclass(t->parms.flowinfo);
 653
 654         if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
 655                 fl6->flowi6_mark = skb->mark;
 656         else
 657                 fl6->flowi6_mark = t->parms.fwmark;
 658
 659         fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
 660 }
 661
 662 static int prepare_ip6gre_xmit_ipv6(struct sk_buff *skb,
 663                                     struct net_device *dev,
 664                                     struct flowi6 *fl6, __u8 *dsfield,
 665                                     int *encap_limit)
 666 {
 667         struct ipv6hdr *ipv6h;
 668         struct ip6_tnl *t = netdev_priv(dev);
 669         __u16 offset;
 670
 671         offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb));
 672         /* ip6_tnl_parse_tlv_enc_lim() might have reallocated skb->head */
 673         ipv6h = ipv6_hdr(skb);
 674
 675         if (offset > 0) {
 676                 struct ipv6_tlv_tnl_enc_lim *tel;
 677
 678                 tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset];
 679                 if (tel->encap_limit == 0) {
 680                         icmpv6_ndo_send(skb, ICMPV6_PARAMPROB,
 681                                         ICMPV6_HDR_FIELD, offset + 2);
 682                         return -1;
 683                 }
 684                 *encap_limit = tel->encap_limit - 1;
 685         } else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) {
 686                 *encap_limit = t->parms.encap_limit;
 687         }
 688
 689         memcpy(fl6, &t->fl.u.ip6, sizeof(*fl6));
 690
 691         if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
 692                 *dsfield = ipv6_get_dsfield(ipv6h);
 693         else
 694                 *dsfield = ip6_tclass(t->parms.flowinfo);
 695
 696         if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL)
 697                 fl6->flowlabel |= ip6_flowlabel(ipv6h);
 698
 699         if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
 700                 fl6->flowi6_mark = skb->mark;
 701         else
 702                 fl6->flowi6_mark = t->parms.fwmark;
 703
 704         fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
 705
 706         return 0;
 707 }
 708
 709 static struct ip_tunnel_info *skb_tunnel_info_txcheck(struct sk_buff *skb)
 710 {
 711         struct ip_tunnel_info *tun_info;
 712
 713         tun_info = skb_tunnel_info(skb);
 714         if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX)))
 715                 return ERR_PTR(-EINVAL);
 716
 717         return tun_info;
 718 }
 719
 720 static netdev_tx_t __gre6_xmit(struct sk_buff *skb,
 721                                struct net_device *dev, __u8 dsfield,
 722                                struct flowi6 *fl6, int encap_limit,
 723                                __u32 *pmtu, __be16 proto)
 724 {
 725         struct ip6_tnl *tunnel = netdev_priv(dev);
 726         __be16 protocol;
 727
 728         if (dev->type == ARPHRD_ETHER)
 729                 IPCB(skb)->flags = 0;
 730
 731         if (dev->header_ops && dev->type == ARPHRD_IP6GRE)
 732                 fl6->daddr = ((struct ipv6hdr *)skb->data)->daddr;
 733         else
 734                 fl6->daddr = tunnel->parms.raddr;
 735
 736         if (skb_cow_head(skb, dev->needed_headroom ?: tunnel->hlen))
 737                 return -ENOMEM;
 738
 739         /* Push GRE header. */
 740         protocol = (dev->type == ARPHRD_ETHER) ? htons(ETH_P_TEB) : proto;
 741
 742         if (tunnel->parms.collect_md) {
 743                 struct ip_tunnel_info *tun_info;
 744                 const struct ip_tunnel_key *key;
 745                 __be16 flags;
 746
 747                 tun_info = skb_tunnel_info_txcheck(skb);
 748                 if (IS_ERR(tun_info) ||
 749                     unlikely(ip_tunnel_info_af(tun_info) != AF_INET6))
 750                         return -EINVAL;
 751
 752                 key = &tun_info->key;
 753                 memset(fl6, 0, sizeof(*fl6));
 754                 fl6->flowi6_proto = IPPROTO_GRE;
 755                 fl6->daddr = key->u.ipv6.dst;
 756                 fl6->flowlabel = key->label;
 757                 fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
 758
 759                 dsfield = key->tos;
 760                 flags = key->tun_flags &
 761                         (TUNNEL_CSUM | TUNNEL_KEY | TUNNEL_SEQ);
 762                 tunnel->tun_hlen = gre_calc_hlen(flags);
 763
 764                 gre_build_header(skb, tunnel->tun_hlen,
 765                                  flags, protocol,
 766                                  tunnel_id_to_key32(tun_info->key.tun_id),
 767                                  (flags & TUNNEL_SEQ) ? htonl(tunnel->o_seqno++)
 768                                                       : 0);
 769
 770         } else {
 771                 if (tunnel->parms.o_flags & TUNNEL_SEQ)
 772                         tunnel->o_seqno++;
 773
 774                 gre_build_header(skb, tunnel->tun_hlen, tunnel->parms.o_flags,
 775                                  protocol, tunnel->parms.o_key,
 776                                  htonl(tunnel->o_seqno));
 777         }
 778
 779         return ip6_tnl_xmit(skb, dev, dsfield, fl6, encap_limit, pmtu,
 780                             NEXTHDR_GRE);
 781 }
 782
 783 static inline int ip6gre_xmit_ipv4(struct sk_buff *skb, struct net_device *dev)
 784 {
 785         struct ip6_tnl *t = netdev_priv(dev);
 786         int encap_limit = -1;
 787         struct flowi6 fl6;
 788         __u8 dsfield = 0;
 789         __u32 mtu;
 790         int err;
 791
 792         memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
 793
 794         if (!t->parms.collect_md)
 795                 prepare_ip6gre_xmit_ipv4(skb, dev, &fl6,
 796                                          &dsfield, &encap_limit);
 797
 798         err = gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM));
 799         if (err)
 800                 return -1;
 801
 802         err = __gre6_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu,
 803                           skb->protocol);
 804         if (err != 0) {
 805                 /* XXX: send ICMP error even if DF is not set. */
 806                 if (err == -EMSGSIZE)
 807                         icmp_ndo_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
 808                                       htonl(mtu));
 809                 return -1;
 810         }
 811
 812         return 0;
 813 }
 814
 815 static inline int ip6gre_xmit_ipv6(struct sk_buff *skb, struct net_device *dev)
 816 {
 817         struct ip6_tnl *t = netdev_priv(dev);
 818         struct ipv6hdr *ipv6h = ipv6_hdr(skb);
 819         int encap_limit = -1;
 820         struct flowi6 fl6;
 821         __u8 dsfield = 0;
 822         __u32 mtu;
 823         int err;
 824
 825         if (ipv6_addr_equal(&t->parms.raddr, &ipv6h->saddr))
 826                 return -1;
 827
 828         if (!t->parms.collect_md &&
 829             prepare_ip6gre_xmit_ipv6(skb, dev, &fl6, &dsfield, &encap_limit))
 830                 return -1;
 831
 832         if (gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM)))
 833                 return -1;
 834
 835         err = __gre6_xmit(skb, dev, dsfield, &fl6, encap_limit,
 836                           &mtu, skb->protocol);
 837         if (err != 0) {
 838                 if (err == -EMSGSIZE)
 839                         icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
 840                 return -1;
 841         }
 842
 843         return 0;
 844 }
 845
 846 /**
 847  * ip6gre_tnl_addr_conflict - compare packet addresses to tunnel's own
 848  *   @t: the outgoing tunnel device
 849  *   @hdr: IPv6 header from the incoming packet
 850  *
 851  * Description:
 852  *   Avoid trivial tunneling loop by checking that tunnel exit-point
 853  *   doesn't match source of incoming packet.
 854  *
 855  * Return:
 856  *   1 if conflict,
 857  *   0 else
 858  **/
 859
 860 static inline bool ip6gre_tnl_addr_conflict(const struct ip6_tnl *t,
 861         const struct ipv6hdr *hdr)
 862 {
 863         return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr);
 864 }
 865
 866 static int ip6gre_xmit_other(struct sk_buff *skb, struct net_device *dev)
 867 {
 868         struct ip6_tnl *t = netdev_priv(dev);
 869         int encap_limit = -1;
 870         struct flowi6 fl6;
 871         __u32 mtu;
 872         int err;
 873
 874         if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
 875                 encap_limit = t->parms.encap_limit;
 876
 877         if (!t->parms.collect_md)
 878                 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
 879
 880         err = gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM));
 881         if (err)
 882                 return err;
 883
 884         err = __gre6_xmit(skb, dev, 0, &fl6, encap_limit, &mtu, skb->protocol);
 885
 886         return err;
 887 }
 888
 889 static netdev_tx_t ip6gre_tunnel_xmit(struct sk_buff *skb,
 890         struct net_device *dev)
 891 {
 892         struct ip6_tnl *t = netdev_priv(dev);
 893         struct net_device_stats *stats = &t->dev->stats;
 894         int ret;
 895
 896         if (!pskb_inet_may_pull(skb))
 897                 goto tx_err;
 898
 899         if (!ip6_tnl_xmit_ctl(t, &t->parms.laddr, &t->parms.raddr))
 900                 goto tx_err;
 901
 902         switch (skb->protocol) {
 903         case htons(ETH_P_IP):
 904                 ret = ip6gre_xmit_ipv4(skb, dev);
 905                 break;
 906         case htons(ETH_P_IPV6):
 907                 ret = ip6gre_xmit_ipv6(skb, dev);
 908                 break;
 909         default:
 910                 ret = ip6gre_xmit_other(skb, dev);
 911                 break;
 912         }
 913
 914         if (ret < 0)
 915                 goto tx_err;
 916
 917         return NETDEV_TX_OK;
 918
 919 tx_err:
 920         if (!t->parms.collect_md || !IS_ERR(skb_tunnel_info_txcheck(skb)))
 921                 stats->tx_errors++;
 922         stats->tx_dropped++;
 923         kfree_skb(skb);
 924         return NETDEV_TX_OK;
 925 }
 926
 927 static netdev_tx_t ip6erspan_tunnel_xmit(struct sk_buff *skb,
 928                                          struct net_device *dev)
 929 {
 930         struct ip_tunnel_info *tun_info = NULL;
 931         struct ip6_tnl *t = netdev_priv(dev);
 932         struct dst_entry *dst = skb_dst(skb);
 933         struct net_device_stats *stats;
 934         bool truncate = false;
 935         int encap_limit = -1;
 936         __u8 dsfield = false;
 937         struct flowi6 fl6;
 938         int err = -EINVAL;
 939         __be16 proto;
 940         __u32 mtu;
 941         int nhoff;
 942         int thoff;
 943
 944         if (!pskb_inet_may_pull(skb))
 945                 goto tx_err;
 946
 947         if (!ip6_tnl_xmit_ctl(t, &t->parms.laddr, &t->parms.raddr))
 948                 goto tx_err;
 949
 950         if (gre_handle_offloads(skb, false))
 951                 goto tx_err;
 952
 953         if (skb->len > dev->mtu + dev->hard_header_len) {
 954                 pskb_trim(skb, dev->mtu + dev->hard_header_len);
 955                 truncate = true;
 956         }
 957
 958         nhoff = skb_network_header(skb) - skb_mac_header(skb);
 959         if (skb->protocol == htons(ETH_P_IP) &&
 960             (ntohs(ip_hdr(skb)->tot_len) > skb->len - nhoff))
 961                 truncate = true;
 962
 963         thoff = skb_transport_header(skb) - skb_mac_header(skb);
 964         if (skb->protocol == htons(ETH_P_IPV6) &&
 965             (ntohs(ipv6_hdr(skb)->payload_len) > skb->len - thoff))
 966                 truncate = true;
 967
 968         if (skb_cow_head(skb, dev->needed_headroom ?: t->hlen))
 969                 goto tx_err;
 970
 971         t->parms.o_flags &= ~TUNNEL_KEY;
 972         IPCB(skb)->flags = 0;
 973
 974         /* For collect_md mode, derive fl6 from the tunnel key,
 975          * for native mode, call prepare_ip6gre_xmit_{ipv4,ipv6}.
 976          */
 977         if (t->parms.collect_md) {
 978                 const struct ip_tunnel_key *key;
 979                 struct erspan_metadata *md;
 980                 __be32 tun_id;
 981
 982                 tun_info = skb_tunnel_info_txcheck(skb);
 983                 if (IS_ERR(tun_info) ||
 984                     unlikely(ip_tunnel_info_af(tun_info) != AF_INET6))
 985                         goto tx_err;
 986
 987                 key = &tun_info->key;
 988                 memset(&fl6, 0, sizeof(fl6));
 989                 fl6.flowi6_proto = IPPROTO_GRE;
 990                 fl6.daddr = key->u.ipv6.dst;
 991                 fl6.flowlabel = key->label;
 992                 fl6.flowi6_uid = sock_net_uid(dev_net(dev), NULL);
 993
 994                 dsfield = key->tos;
 995                 if (!(tun_info->key.tun_flags & TUNNEL_ERSPAN_OPT))
 996                         goto tx_err;
 997                 if (tun_info->options_len < sizeof(*md))
 998                         goto tx_err;
 999                 md = ip_tunnel_info_opts(tun_info);
1000
1001                 tun_id = tunnel_id_to_key32(key->tun_id);
1002                 if (md->version == 1) {
1003                         erspan_build_header(skb,
1004                                             ntohl(tun_id),
1005                                             ntohl(md->u.index), truncate,
1006                                             false);
1007                 } else if (md->version == 2) {
1008                         erspan_build_header_v2(skb,
1009                                                ntohl(tun_id),
1010                                                md->u.md2.dir,
1011                                                get_hwid(&md->u.md2),
1012                                                truncate, false);
1013                 } else {
1014                         goto tx_err;
1015                 }
1016         } else {
1017                 switch (skb->protocol) {
1018                 case htons(ETH_P_IP):
1019                         memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
1020                         prepare_ip6gre_xmit_ipv4(skb, dev, &fl6,
1021                                                  &dsfield, &encap_limit);
1022                         break;
1023                 case htons(ETH_P_IPV6):
1024                         if (ipv6_addr_equal(&t->parms.raddr, &ipv6_hdr(skb)->saddr))
1025                                 goto tx_err;
1026                         if (prepare_ip6gre_xmit_ipv6(skb, dev, &fl6,
1027                                                      &dsfield, &encap_limit))
1028                                 goto tx_err;
1029                         break;
1030                 default:
1031                         memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
1032                         break;
1033                 }
1034
1035                 if (t->parms.erspan_ver == 1)
1036                         erspan_build_header(skb, ntohl(t->parms.o_key),
1037                                             t->parms.index,
1038                                             truncate, false);
1039                 else if (t->parms.erspan_ver == 2)
1040                         erspan_build_header_v2(skb, ntohl(t->parms.o_key),
1041                                                t->parms.dir,
1042                                                t->parms.hwid,
1043                                                truncate, false);
1044                 else
1045                         goto tx_err;
1046
1047                 fl6.daddr = t->parms.raddr;
1048         }
1049
1050         /* Push GRE header. */
1051         proto = (t->parms.erspan_ver == 1) ? htons(ETH_P_ERSPAN)
1052                                            : htons(ETH_P_ERSPAN2);
1053         gre_build_header(skb, 8, TUNNEL_SEQ, proto, 0, htonl(t->o_seqno++));
1054
1055         /* TooBig packet may have updated dst->dev's mtu */
1056         if (!t->parms.collect_md && dst && dst_mtu(dst) > dst->dev->mtu)
1057                 dst->ops->update_pmtu(dst, NULL, skb, dst->dev->mtu, false);
1058
1059         err = ip6_tnl_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu,
1060                            NEXTHDR_GRE);
1061         if (err != 0) {
1062                 /* XXX: send ICMP error even if DF is not set. */
1063                 if (err == -EMSGSIZE) {
1064                         if (skb->protocol == htons(ETH_P_IP))
1065                                 icmp_ndo_send(skb, ICMP_DEST_UNREACH,
1066                                               ICMP_FRAG_NEEDED, htonl(mtu));
1067                         else
1068                                 icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
1069                 }
1070
1071                 goto tx_err;
1072         }
1073         return NETDEV_TX_OK;
1074
1075 tx_err:
1076         stats = &t->dev->stats;
1077         if (!IS_ERR(tun_info))
1078                 stats->tx_errors++;
1079         stats->tx_dropped++;
1080         kfree_skb(skb);
1081         return NETDEV_TX_OK;
1082 }
1083
1084 static void ip6gre_tnl_link_config_common(struct ip6_tnl *t)
1085 {
1086         struct net_device *dev = t->dev;
1087         struct __ip6_tnl_parm *p = &t->parms;
1088         struct flowi6 *fl6 = &t->fl.u.ip6;
1089
1090         if (dev->type != ARPHRD_ETHER) {
1091                 memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr));
1092                 memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr));
1093         }
1094
1095         /* Set up flowi template */
1096         fl6->saddr = p->laddr;
1097         fl6->daddr = p->raddr;
1098         fl6->flowi6_oif = p->link;
1099         fl6->flowlabel = 0;
1100         fl6->flowi6_proto = IPPROTO_GRE;
1101
1102         if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS))
1103                 fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo;
1104         if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL))
1105                 fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo;
1106
1107         p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET);
1108         p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr);
1109
1110         if (p->flags&IP6_TNL_F_CAP_XMIT &&
1111                         p->flags&IP6_TNL_F_CAP_RCV && dev->type != ARPHRD_ETHER)
1112                 dev->flags |= IFF_POINTOPOINT;
1113         else
1114                 dev->flags &= ~IFF_POINTOPOINT;
1115 }
1116
1117 static void ip6gre_tnl_link_config_route(struct ip6_tnl *t, int set_mtu,
1118                                          int t_hlen)
1119 {
1120         const struct __ip6_tnl_parm *p = &t->parms;
1121         struct net_device *dev = t->dev;
1122
1123         if (p->flags & IP6_TNL_F_CAP_XMIT) {
1124                 int strict = (ipv6_addr_type(&p->raddr) &
1125                               (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL));
1126
1127                 struct rt6_info *rt = rt6_lookup(t->net,
1128                                                  &p->raddr, &p->laddr,
1129                                                  p->link, NULL, strict);
1130
1131                 if (!rt)
1132                         return;
1133
1134                 if (rt->dst.dev) {
1135                         unsigned short dst_len = rt->dst.dev->hard_header_len +
1136                                                  t_hlen;
1137
1138                         if (t->dev->header_ops)
1139                                 dev->hard_header_len = dst_len;
1140                         else
1141                                 dev->needed_headroom = dst_len;
1142
1143                         if (set_mtu) {
1144                                 dev->mtu = rt->dst.dev->mtu - t_hlen;
1145                                 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1146                                         dev->mtu -= 8;
1147                                 if (dev->type == ARPHRD_ETHER)
1148                                         dev->mtu -= ETH_HLEN;
1149
1150                                 if (dev->mtu < IPV6_MIN_MTU)
1151                                         dev->mtu = IPV6_MIN_MTU;
1152                         }
1153                 }
1154                 ip6_rt_put(rt);
1155         }
1156 }
1157
1158 static int ip6gre_calc_hlen(struct ip6_tnl *tunnel)
1159 {
1160         int t_hlen;
1161
1162         tunnel->tun_hlen = gre_calc_hlen(tunnel->parms.o_flags);
1163         tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen;
1164
1165         t_hlen = tunnel->hlen + sizeof(struct ipv6hdr);
1166
1167         if (tunnel->dev->header_ops)
1168                 tunnel->dev->hard_header_len = LL_MAX_HEADER + t_hlen;
1169         else
1170                 tunnel->dev->needed_headroom = LL_MAX_HEADER + t_hlen;
1171
1172         return t_hlen;
1173 }
1174
1175 static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu)
1176 {
1177         ip6gre_tnl_link_config_common(t);
1178         ip6gre_tnl_link_config_route(t, set_mtu, ip6gre_calc_hlen(t));
1179 }
1180
1181 static void ip6gre_tnl_copy_tnl_parm(struct ip6_tnl *t,
1182                                      const struct __ip6_tnl_parm *p)
1183 {
1184         t->parms.laddr = p->laddr;
1185         t->parms.raddr = p->raddr;
1186         t->parms.flags = p->flags;
1187         t->parms.hop_limit = p->hop_limit;
1188         t->parms.encap_limit = p->encap_limit;
1189         t->parms.flowinfo = p->flowinfo;
1190         t->parms.link = p->link;
1191         t->parms.proto = p->proto;
1192         t->parms.i_key = p->i_key;
1193         t->parms.o_key = p->o_key;
1194         t->parms.i_flags = p->i_flags;
1195         t->parms.o_flags = p->o_flags;
1196         t->parms.fwmark = p->fwmark;
1197         t->parms.erspan_ver = p->erspan_ver;
1198         t->parms.index = p->index;
1199         t->parms.dir = p->dir;
1200         t->parms.hwid = p->hwid;
1201         dst_cache_reset(&t->dst_cache);
1202 }
1203
1204 static int ip6gre_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p,
1205                              int set_mtu)
1206 {
1207         ip6gre_tnl_copy_tnl_parm(t, p);
1208         ip6gre_tnl_link_config(t, set_mtu);
1209         return 0;
1210 }
1211
1212 static void ip6gre_tnl_parm_from_user(struct __ip6_tnl_parm *p,
1213         const struct ip6_tnl_parm2 *u)
1214 {
1215         p->laddr = u->laddr;
1216         p->raddr = u->raddr;
1217         p->flags = u->flags;
1218         p->hop_limit = u->hop_limit;
1219         p->encap_limit = u->encap_limit;
1220         p->flowinfo = u->flowinfo;
1221         p->link = u->link;
1222         p->i_key = u->i_key;
1223         p->o_key = u->o_key;
1224         p->i_flags = gre_flags_to_tnl_flags(u->i_flags);
1225         p->o_flags = gre_flags_to_tnl_flags(u->o_flags);
1226         memcpy(p->name, u->name, sizeof(u->name));
1227 }
1228
1229 static void ip6gre_tnl_parm_to_user(struct ip6_tnl_parm2 *u,
1230         const struct __ip6_tnl_parm *p)
1231 {
1232         u->proto = IPPROTO_GRE;
1233         u->laddr = p->laddr;
1234         u->raddr = p->raddr;
1235         u->flags = p->flags;
1236         u->hop_limit = p->hop_limit;
1237         u->encap_limit = p->encap_limit;
1238         u->flowinfo = p->flowinfo;
1239         u->link = p->link;
1240         u->i_key = p->i_key;
1241         u->o_key = p->o_key;
1242         u->i_flags = gre_tnl_flags_to_gre_flags(p->i_flags);
1243         u->o_flags = gre_tnl_flags_to_gre_flags(p->o_flags);
1244         memcpy(u->name, p->name, sizeof(u->name));
1245 }
1246
1247 static int ip6gre_tunnel_ioctl(struct net_device *dev,
1248         struct ifreq *ifr, int cmd)
1249 {
1250         int err = 0;
1251         struct ip6_tnl_parm2 p;
1252         struct __ip6_tnl_parm p1;
1253         struct ip6_tnl *t = netdev_priv(dev);
1254         struct net *net = t->net;
1255         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1256
1257         memset(&p1, 0, sizeof(p1));
1258
1259         switch (cmd) {
1260         case SIOCGETTUNNEL:
1261                 if (dev == ign->fb_tunnel_dev) {
1262                         if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
1263                                 err = -EFAULT;
1264                                 break;
1265                         }
1266                         ip6gre_tnl_parm_from_user(&p1, &p);
1267                         t = ip6gre_tunnel_locate(net, &p1, 0);
1268                         if (!t)
1269                                 t = netdev_priv(dev);
1270                 }
1271                 memset(&p, 0, sizeof(p));
1272                 ip6gre_tnl_parm_to_user(&p, &t->parms);
1273                 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
1274                         err = -EFAULT;
1275                 break;
1276
1277         case SIOCADDTUNNEL:
1278         case SIOCCHGTUNNEL:
1279                 err = -EPERM;
1280                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1281                         goto done;
1282
1283                 err = -EFAULT;
1284                 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
1285                         goto done;
1286
1287                 err = -EINVAL;
1288                 if ((p.i_flags|p.o_flags)&(GRE_VERSION|GRE_ROUTING))
1289                         goto done;
1290
1291                 if (!(p.i_flags&GRE_KEY))
1292                         p.i_key = 0;
1293                 if (!(p.o_flags&GRE_KEY))
1294                         p.o_key = 0;
1295
1296                 ip6gre_tnl_parm_from_user(&p1, &p);
1297                 t = ip6gre_tunnel_locate(net, &p1, cmd == SIOCADDTUNNEL);
1298
1299                 if (dev != ign->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
1300                         if (t) {
1301                                 if (t->dev != dev) {
1302                                         err = -EEXIST;
1303                                         break;
1304                                 }
1305                         } else {
1306                                 t = netdev_priv(dev);
1307
1308                                 ip6gre_tunnel_unlink(ign, t);
1309                                 synchronize_net();
1310                                 ip6gre_tnl_change(t, &p1, 1);
1311                                 ip6gre_tunnel_link(ign, t);
1312                                 netdev_state_change(dev);
1313                         }
1314                 }
1315
1316                 if (t) {
1317                         err = 0;
1318
1319                         memset(&p, 0, sizeof(p));
1320                         ip6gre_tnl_parm_to_user(&p, &t->parms);
1321                         if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
1322                                 err = -EFAULT;
1323                 } else
1324                         err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
1325                 break;
1326
1327         case SIOCDELTUNNEL:
1328                 err = -EPERM;
1329                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1330                         goto done;
1331
1332                 if (dev == ign->fb_tunnel_dev) {
1333                         err = -EFAULT;
1334                         if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
1335                                 goto done;
1336                         err = -ENOENT;
1337                         ip6gre_tnl_parm_from_user(&p1, &p);
1338                         t = ip6gre_tunnel_locate(net, &p1, 0);
1339                         if (!t)
1340                                 goto done;
1341                         err = -EPERM;
1342                         if (t == netdev_priv(ign->fb_tunnel_dev))
1343                                 goto done;
1344                         dev = t->dev;
1345                 }
1346                 unregister_netdevice(dev);
1347                 err = 0;
1348                 break;
1349
1350         default:
1351                 err = -EINVAL;
1352         }
1353
1354 done:
1355         return err;
1356 }
1357
1358 static int ip6gre_header(struct sk_buff *skb, struct net_device *dev,
1359                          unsigned short type, const void *daddr,
1360                          const void *saddr, unsigned int len)
1361 {
1362         struct ip6_tnl *t = netdev_priv(dev);
1363         struct ipv6hdr *ipv6h;
1364         __be16 *p;
1365
1366         ipv6h = skb_push(skb, t->hlen + sizeof(*ipv6h));
1367         ip6_flow_hdr(ipv6h, 0, ip6_make_flowlabel(dev_net(dev), skb,
1368                                                   t->fl.u.ip6.flowlabel,
1369                                                   true, &t->fl.u.ip6));
1370         ipv6h->hop_limit = t->parms.hop_limit;
1371         ipv6h->nexthdr = NEXTHDR_GRE;
1372         ipv6h->saddr = t->parms.laddr;
1373         ipv6h->daddr = t->parms.raddr;
1374
1375         p = (__be16 *)(ipv6h + 1);
1376         p[0] = t->parms.o_flags;
1377         p[1] = htons(type);
1378
1379         /*
1380          *      Set the source hardware address.
1381          */
1382
1383         if (saddr)
1384                 memcpy(&ipv6h->saddr, saddr, sizeof(struct in6_addr));
1385         if (daddr)
1386                 memcpy(&ipv6h->daddr, daddr, sizeof(struct in6_addr));
1387         if (!ipv6_addr_any(&ipv6h->daddr))
1388                 return t->hlen;
1389
1390         return -t->hlen;
1391 }
1392
1393 static const struct header_ops ip6gre_header_ops = {
1394         .create = ip6gre_header,
1395 };
1396
1397 static const struct net_device_ops ip6gre_netdev_ops = {
1398         .ndo_init               = ip6gre_tunnel_init,
1399         .ndo_uninit             = ip6gre_tunnel_uninit,
1400         .ndo_start_xmit         = ip6gre_tunnel_xmit,
1401         .ndo_do_ioctl           = ip6gre_tunnel_ioctl,
1402         .ndo_change_mtu         = ip6_tnl_change_mtu,
1403         .ndo_get_stats64        = dev_get_tstats64,
1404         .ndo_get_iflink         = ip6_tnl_get_iflink,
1405 };
1406
1407 static void ip6gre_dev_free(struct net_device *dev)
1408 {
1409         struct ip6_tnl *t = netdev_priv(dev);
1410
1411         gro_cells_destroy(&t->gro_cells);
1412         dst_cache_destroy(&t->dst_cache);
1413         free_percpu(dev->tstats);
1414 }
1415
1416 static void ip6gre_tunnel_setup(struct net_device *dev)
1417 {
1418         dev->netdev_ops = &ip6gre_netdev_ops;
1419         dev->needs_free_netdev = true;
1420         dev->priv_destructor = ip6gre_dev_free;
1421
1422         dev->type = ARPHRD_IP6GRE;
1423
1424         dev->flags |= IFF_NOARP;
1425         dev->addr_len = sizeof(struct in6_addr);
1426         netif_keep_dst(dev);
1427         /* This perm addr will be used as interface identifier by IPv6 */
1428         dev->addr_assign_type = NET_ADDR_RANDOM;
1429         eth_random_addr(dev->perm_addr);
1430 }
1431
1432 #define GRE6_FEATURES (NETIF_F_SG |             \
1433                        NETIF_F_FRAGLIST |       \
1434                        NETIF_F_HIGHDMA |        \
1435                        NETIF_F_HW_CSUM)
1436
1437 static void ip6gre_tnl_init_features(struct net_device *dev)
1438 {
1439         struct ip6_tnl *nt = netdev_priv(dev);
1440
1441         dev->features           |= GRE6_FEATURES;
1442         dev->hw_features        |= GRE6_FEATURES;
1443
1444         if (!(nt->parms.o_flags & TUNNEL_SEQ)) {
1445                 /* TCP offload with GRE SEQ is not supported, nor
1446                  * can we support 2 levels of outer headers requiring
1447                  * an update.
1448                  */
1449                 if (!(nt->parms.o_flags & TUNNEL_CSUM) ||
1450                     nt->encap.type == TUNNEL_ENCAP_NONE) {
1451                         dev->features    |= NETIF_F_GSO_SOFTWARE;
1452                         dev->hw_features |= NETIF_F_GSO_SOFTWARE;
1453                 }
1454
1455                 /* Can use a lockless transmit, unless we generate
1456                  * output sequences
1457                  */
1458                 dev->features |= NETIF_F_LLTX;
1459         }
1460 }
1461
1462 static int ip6gre_tunnel_init_common(struct net_device *dev)
1463 {
1464         struct ip6_tnl *tunnel;
1465         int ret;
1466         int t_hlen;
1467
1468         tunnel = netdev_priv(dev);
1469
1470         tunnel->dev = dev;
1471         tunnel->net = dev_net(dev);
1472         strcpy(tunnel->parms.name, dev->name);
1473
1474         dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1475         if (!dev->tstats)
1476                 return -ENOMEM;
1477
1478         ret = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
1479         if (ret)
1480                 goto cleanup_alloc_pcpu_stats;
1481
1482         ret = gro_cells_init(&tunnel->gro_cells, dev);
1483         if (ret)
1484                 goto cleanup_dst_cache_init;
1485
1486         t_hlen = ip6gre_calc_hlen(tunnel);
1487         dev->mtu = ETH_DATA_LEN - t_hlen;
1488         if (dev->type == ARPHRD_ETHER)
1489                 dev->mtu -= ETH_HLEN;
1490         if (!(tunnel->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1491                 dev->mtu -= 8;
1492
1493         if (tunnel->parms.collect_md) {
1494                 netif_keep_dst(dev);
1495         }
1496         ip6gre_tnl_init_features(dev);
1497
1498         dev_hold(dev);
1499         return 0;
1500
1501 cleanup_dst_cache_init:
1502         dst_cache_destroy(&tunnel->dst_cache);
1503 cleanup_alloc_pcpu_stats:
1504         free_percpu(dev->tstats);
1505         dev->tstats = NULL;
1506         return ret;
1507 }
1508
1509 static int ip6gre_tunnel_init(struct net_device *dev)
1510 {
1511         struct ip6_tnl *tunnel;
1512         int ret;
1513
1514         ret = ip6gre_tunnel_init_common(dev);
1515         if (ret)
1516                 return ret;
1517
1518         tunnel = netdev_priv(dev);
1519
1520         if (tunnel->parms.collect_md)
1521                 return 0;
1522
1523         memcpy(dev->dev_addr, &tunnel->parms.laddr, sizeof(struct in6_addr));
1524         memcpy(dev->broadcast, &tunnel->parms.raddr, sizeof(struct in6_addr));
1525
1526         if (ipv6_addr_any(&tunnel->parms.raddr))
1527                 dev->header_ops = &ip6gre_header_ops;
1528
1529         return 0;
1530 }
1531
1532 static void ip6gre_fb_tunnel_init(struct net_device *dev)
1533 {
1534         struct ip6_tnl *tunnel = netdev_priv(dev);
1535
1536         tunnel->dev = dev;
1537         tunnel->net = dev_net(dev);
1538         strcpy(tunnel->parms.name, dev->name);
1539
1540         tunnel->hlen            = sizeof(struct ipv6hdr) + 4;
1541 }
1542
1543 static struct inet6_protocol ip6gre_protocol __read_mostly = {
1544         .handler     = gre_rcv,
1545         .err_handler = ip6gre_err,
1546         .flags       = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
1547 };
1548
1549 static void ip6gre_destroy_tunnels(struct net *net, struct list_head *head)
1550 {
1551         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1552         struct net_device *dev, *aux;
1553         int prio;
1554
1555         for_each_netdev_safe(net, dev, aux)
1556                 if (dev->rtnl_link_ops == &ip6gre_link_ops ||
1557                     dev->rtnl_link_ops == &ip6gre_tap_ops ||
1558                     dev->rtnl_link_ops == &ip6erspan_tap_ops)
1559                         unregister_netdevice_queue(dev, head);
1560
1561         for (prio = 0; prio < 4; prio++) {
1562                 int h;
1563                 for (h = 0; h < IP6_GRE_HASH_SIZE; h++) {
1564                         struct ip6_tnl *t;
1565
1566                         t = rtnl_dereference(ign->tunnels[prio][h]);
1567
1568                         while (t) {
1569                                 /* If dev is in the same netns, it has already
1570                                  * been added to the list by the previous loop.
1571                                  */
1572                                 if (!net_eq(dev_net(t->dev), net))
1573                                         unregister_netdevice_queue(t->dev,
1574                                                                    head);
1575                                 t = rtnl_dereference(t->next);
1576                         }
1577                 }
1578         }
1579 }
1580
1581 static int __net_init ip6gre_init_net(struct net *net)
1582 {
1583         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1584         struct net_device *ndev;
1585         int err;
1586
1587         if (!net_has_fallback_tunnels(net))
1588                 return 0;
1589         ndev = alloc_netdev(sizeof(struct ip6_tnl), "ip6gre0",
1590                             NET_NAME_UNKNOWN, ip6gre_tunnel_setup);
1591         if (!ndev) {
1592                 err = -ENOMEM;
1593                 goto err_alloc_dev;
1594         }
1595         ign->fb_tunnel_dev = ndev;
1596         dev_net_set(ign->fb_tunnel_dev, net);
1597         /* FB netdevice is special: we have one, and only one per netns.
1598          * Allowing to move it to another netns is clearly unsafe.
1599          */
1600         ign->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL;
1601
1602
1603         ip6gre_fb_tunnel_init(ign->fb_tunnel_dev);
1604         ign->fb_tunnel_dev->rtnl_link_ops = &ip6gre_link_ops;
1605
1606         err = register_netdev(ign->fb_tunnel_dev);
1607         if (err)
1608                 goto err_reg_dev;
1609
1610         rcu_assign_pointer(ign->tunnels_wc[0],
1611                            netdev_priv(ign->fb_tunnel_dev));
1612         return 0;
1613
1614 err_reg_dev:
1615         free_netdev(ndev);
1616 err_alloc_dev:
1617         return err;
1618 }
1619
1620 static void __net_exit ip6gre_exit_batch_net(struct list_head *net_list)
1621 {
1622         struct net *net;
1623         LIST_HEAD(list);
1624
1625         rtnl_lock();
1626         list_for_each_entry(net, net_list, exit_list)
1627                 ip6gre_destroy_tunnels(net, &list);
1628         unregister_netdevice_many(&list);
1629         rtnl_unlock();
1630 }
1631
1632 static struct pernet_operations ip6gre_net_ops = {
1633         .init = ip6gre_init_net,
1634         .exit_batch = ip6gre_exit_batch_net,
1635         .id   = &ip6gre_net_id,
1636         .size = sizeof(struct ip6gre_net),
1637 };
1638
1639 static int ip6gre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[],
1640                                   struct netlink_ext_ack *extack)
1641 {
1642         __be16 flags;
1643
1644         if (!data)
1645                 return 0;
1646
1647         flags = 0;
1648         if (data[IFLA_GRE_IFLAGS])
1649                 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
1650         if (data[IFLA_GRE_OFLAGS])
1651                 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
1652         if (flags & (GRE_VERSION|GRE_ROUTING))
1653                 return -EINVAL;
1654
1655         return 0;
1656 }
1657
1658 static int ip6gre_tap_validate(struct nlattr *tb[], struct nlattr *data[],
1659                                struct netlink_ext_ack *extack)
1660 {
1661         struct in6_addr daddr;
1662
1663         if (tb[IFLA_ADDRESS]) {
1664                 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
1665                         return -EINVAL;
1666                 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
1667                         return -EADDRNOTAVAIL;
1668         }
1669
1670         if (!data)
1671                 goto out;
1672
1673         if (data[IFLA_GRE_REMOTE]) {
1674                 daddr = nla_get_in6_addr(data[IFLA_GRE_REMOTE]);
1675                 if (ipv6_addr_any(&daddr))
1676                         return -EINVAL;
1677         }
1678
1679 out:
1680         return ip6gre_tunnel_validate(tb, data, extack);
1681 }
1682
1683 static int ip6erspan_tap_validate(struct nlattr *tb[], struct nlattr *data[],
1684                                   struct netlink_ext_ack *extack)
1685 {
1686         __be16 flags = 0;
1687         int ret, ver = 0;
1688
1689         if (!data)
1690                 return 0;
1691
1692         ret = ip6gre_tap_validate(tb, data, extack);
1693         if (ret)
1694                 return ret;
1695
1696         /* ERSPAN should only have GRE sequence and key flag */
1697         if (data[IFLA_GRE_OFLAGS])
1698                 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
1699         if (data[IFLA_GRE_IFLAGS])
1700                 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
1701         if (!data[IFLA_GRE_COLLECT_METADATA] &&
1702             flags != (GRE_SEQ | GRE_KEY))
1703                 return -EINVAL;
1704
1705         /* ERSPAN Session ID only has 10-bit. Since we reuse
1706          * 32-bit key field as ID, check it's range.
1707          */
1708         if (data[IFLA_GRE_IKEY] &&
1709             (ntohl(nla_get_be32(data[IFLA_GRE_IKEY])) & ~ID_MASK))
1710                 return -EINVAL;
1711
1712         if (data[IFLA_GRE_OKEY] &&
1713             (ntohl(nla_get_be32(data[IFLA_GRE_OKEY])) & ~ID_MASK))
1714                 return -EINVAL;
1715
1716         if (data[IFLA_GRE_ERSPAN_VER]) {
1717                 ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]);
1718                 if (ver != 1 && ver != 2)
1719                         return -EINVAL;
1720         }
1721
1722         if (ver == 1) {
1723                 if (data[IFLA_GRE_ERSPAN_INDEX]) {
1724                         u32 index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]);
1725
1726                         if (index & ~INDEX_MASK)
1727                                 return -EINVAL;
1728                 }
1729         } else if (ver == 2) {
1730                 if (data[IFLA_GRE_ERSPAN_DIR]) {
1731                         u16 dir = nla_get_u8(data[IFLA_GRE_ERSPAN_DIR]);
1732
1733                         if (dir & ~(DIR_MASK >> DIR_OFFSET))
1734                                 return -EINVAL;
1735                 }
1736
1737                 if (data[IFLA_GRE_ERSPAN_HWID]) {
1738                         u16 hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]);
1739
1740                         if (hwid & ~(HWID_MASK >> HWID_OFFSET))
1741                                 return -EINVAL;
1742                 }
1743         }
1744
1745         return 0;
1746 }
1747
1748 static void ip6erspan_set_version(struct nlattr *data[],
1749                                   struct __ip6_tnl_parm *parms)
1750 {
1751         if (!data)
1752                 return;
1753
1754         parms->erspan_ver = 1;
1755         if (data[IFLA_GRE_ERSPAN_VER])
1756                 parms->erspan_ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]);
1757
1758         if (parms->erspan_ver == 1) {
1759                 if (data[IFLA_GRE_ERSPAN_INDEX])
1760                         parms->index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]);
1761         } else if (parms->erspan_ver == 2) {
1762                 if (data[IFLA_GRE_ERSPAN_DIR])
1763                         parms->dir = nla_get_u8(data[IFLA_GRE_ERSPAN_DIR]);
1764                 if (data[IFLA_GRE_ERSPAN_HWID])
1765                         parms->hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]);
1766         }
1767 }
1768
1769 static void ip6gre_netlink_parms(struct nlattr *data[],
1770                                 struct __ip6_tnl_parm *parms)
1771 {
1772         memset(parms, 0, sizeof(*parms));
1773
1774         if (!data)
1775                 return;
1776
1777         if (data[IFLA_GRE_LINK])
1778                 parms->link = nla_get_u32(data[IFLA_GRE_LINK]);
1779
1780         if (data[IFLA_GRE_IFLAGS])
1781                 parms->i_flags = gre_flags_to_tnl_flags(
1782                                 nla_get_be16(data[IFLA_GRE_IFLAGS]));
1783
1784         if (data[IFLA_GRE_OFLAGS])
1785                 parms->o_flags = gre_flags_to_tnl_flags(
1786                                 nla_get_be16(data[IFLA_GRE_OFLAGS]));
1787
1788         if (data[IFLA_GRE_IKEY])
1789                 parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]);
1790
1791         if (data[IFLA_GRE_OKEY])
1792                 parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]);
1793
1794         if (data[IFLA_GRE_LOCAL])
1795                 parms->laddr = nla_get_in6_addr(data[IFLA_GRE_LOCAL]);
1796
1797         if (data[IFLA_GRE_REMOTE])
1798                 parms->raddr = nla_get_in6_addr(data[IFLA_GRE_REMOTE]);
1799
1800         if (data[IFLA_GRE_TTL])
1801                 parms->hop_limit = nla_get_u8(data[IFLA_GRE_TTL]);
1802
1803         if (data[IFLA_GRE_ENCAP_LIMIT])
1804                 parms->encap_limit = nla_get_u8(data[IFLA_GRE_ENCAP_LIMIT]);
1805
1806         if (data[IFLA_GRE_FLOWINFO])
1807                 parms->flowinfo = nla_get_be32(data[IFLA_GRE_FLOWINFO]);
1808
1809         if (data[IFLA_GRE_FLAGS])
1810                 parms->flags = nla_get_u32(data[IFLA_GRE_FLAGS]);
1811
1812         if (data[IFLA_GRE_FWMARK])
1813                 parms->fwmark = nla_get_u32(data[IFLA_GRE_FWMARK]);
1814
1815         if (data[IFLA_GRE_COLLECT_METADATA])
1816                 parms->collect_md = true;
1817 }
1818
1819 static int ip6gre_tap_init(struct net_device *dev)
1820 {
1821         int ret;
1822
1823         ret = ip6gre_tunnel_init_common(dev);
1824         if (ret)
1825                 return ret;
1826
1827         dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1828
1829         return 0;
1830 }
1831
1832 static const struct net_device_ops ip6gre_tap_netdev_ops = {
1833         .ndo_init = ip6gre_tap_init,
1834         .ndo_uninit = ip6gre_tunnel_uninit,
1835         .ndo_start_xmit = ip6gre_tunnel_xmit,
1836         .ndo_set_mac_address = eth_mac_addr,
1837         .ndo_validate_addr = eth_validate_addr,
1838         .ndo_change_mtu = ip6_tnl_change_mtu,
1839         .ndo_get_stats64 = dev_get_tstats64,
1840         .ndo_get_iflink = ip6_tnl_get_iflink,
1841 };
1842
1843 static int ip6erspan_calc_hlen(struct ip6_tnl *tunnel)
1844 {
1845         int t_hlen;
1846
1847         tunnel->tun_hlen = 8;
1848         tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen +
1849                        erspan_hdr_len(tunnel->parms.erspan_ver);
1850
1851         t_hlen = tunnel->hlen + sizeof(struct ipv6hdr);
1852         tunnel->dev->needed_headroom = LL_MAX_HEADER + t_hlen;
1853         return t_hlen;
1854 }
1855
1856 static int ip6erspan_tap_init(struct net_device *dev)
1857 {
1858         struct ip6_tnl *tunnel;
1859         int t_hlen;
1860         int ret;
1861
1862         tunnel = netdev_priv(dev);
1863
1864         tunnel->dev = dev;
1865         tunnel->net = dev_net(dev);
1866         strcpy(tunnel->parms.name, dev->name);
1867
1868         dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1869         if (!dev->tstats)
1870                 return -ENOMEM;
1871
1872         ret = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
1873         if (ret)
1874                 goto cleanup_alloc_pcpu_stats;
1875
1876         ret = gro_cells_init(&tunnel->gro_cells, dev);
1877         if (ret)
1878                 goto cleanup_dst_cache_init;
1879
1880         t_hlen = ip6erspan_calc_hlen(tunnel);
1881         dev->mtu = ETH_DATA_LEN - t_hlen;
1882         if (dev->type == ARPHRD_ETHER)
1883                 dev->mtu -= ETH_HLEN;
1884         if (!(tunnel->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1885                 dev->mtu -= 8;
1886
1887         dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1888         ip6erspan_tnl_link_config(tunnel, 1);
1889
1890         dev_hold(dev);
1891         return 0;
1892
1893 cleanup_dst_cache_init:
1894         dst_cache_destroy(&tunnel->dst_cache);
1895 cleanup_alloc_pcpu_stats:
1896         free_percpu(dev->tstats);
1897         dev->tstats = NULL;
1898         return ret;
1899 }
1900
1901 static const struct net_device_ops ip6erspan_netdev_ops = {
1902         .ndo_init =             ip6erspan_tap_init,
1903         .ndo_uninit =           ip6erspan_tunnel_uninit,
1904         .ndo_start_xmit =       ip6erspan_tunnel_xmit,
1905         .ndo_set_mac_address =  eth_mac_addr,
1906         .ndo_validate_addr =    eth_validate_addr,
1907         .ndo_change_mtu =       ip6_tnl_change_mtu,
1908         .ndo_get_stats64 =      dev_get_tstats64,
1909         .ndo_get_iflink =       ip6_tnl_get_iflink,
1910 };
1911
1912 static void ip6gre_tap_setup(struct net_device *dev)
1913 {
1914
1915         ether_setup(dev);
1916
1917         dev->max_mtu = 0;
1918         dev->netdev_ops = &ip6gre_tap_netdev_ops;
1919         dev->needs_free_netdev = true;
1920         dev->priv_destructor = ip6gre_dev_free;
1921
1922         dev->priv_flags &= ~IFF_TX_SKB_SHARING;
1923         dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1924         netif_keep_dst(dev);
1925 }
1926
1927 static bool ip6gre_netlink_encap_parms(struct nlattr *data[],
1928                                        struct ip_tunnel_encap *ipencap)
1929 {
1930         bool ret = false;
1931
1932         memset(ipencap, 0, sizeof(*ipencap));
1933
1934         if (!data)
1935                 return ret;
1936
1937         if (data[IFLA_GRE_ENCAP_TYPE]) {
1938                 ret = true;
1939                 ipencap->type = nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]);
1940         }
1941
1942         if (data[IFLA_GRE_ENCAP_FLAGS]) {
1943                 ret = true;
1944                 ipencap->flags = nla_get_u16(data[IFLA_GRE_ENCAP_FLAGS]);
1945         }
1946
1947         if (data[IFLA_GRE_ENCAP_SPORT]) {
1948                 ret = true;
1949                 ipencap->sport = nla_get_be16(data[IFLA_GRE_ENCAP_SPORT]);
1950         }
1951
1952         if (data[IFLA_GRE_ENCAP_DPORT]) {
1953                 ret = true;
1954                 ipencap->dport = nla_get_be16(data[IFLA_GRE_ENCAP_DPORT]);
1955         }
1956
1957         return ret;
1958 }
1959
1960 static int ip6gre_newlink_common(struct net *src_net, struct net_device *dev,
1961                                  struct nlattr *tb[], struct nlattr *data[],
1962                                  struct netlink_ext_ack *extack)
1963 {
1964         struct ip6_tnl *nt;
1965         struct ip_tunnel_encap ipencap;
1966         int err;
1967
1968         nt = netdev_priv(dev);
1969
1970         if (ip6gre_netlink_encap_parms(data, &ipencap)) {
1971                 int err = ip6_tnl_encap_setup(nt, &ipencap);
1972
1973                 if (err < 0)
1974                         return err;
1975         }
1976
1977         if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS])
1978                 eth_hw_addr_random(dev);
1979
1980         nt->dev = dev;
1981         nt->net = dev_net(dev);
1982
1983         err = register_netdevice(dev);
1984         if (err)
1985                 goto out;
1986
1987         if (tb[IFLA_MTU])
1988                 ip6_tnl_change_mtu(dev, nla_get_u32(tb[IFLA_MTU]));
1989
1990 out:
1991         return err;
1992 }
1993
1994 static int ip6gre_newlink(struct net *src_net, struct net_device *dev,
1995                           struct nlattr *tb[], struct nlattr *data[],
1996                           struct netlink_ext_ack *extack)
1997 {
1998         struct ip6_tnl *nt = netdev_priv(dev);
1999         struct net *net = dev_net(dev);
2000         struct ip6gre_net *ign;
2001         int err;
2002
2003         ip6gre_netlink_parms(data, &nt->parms);
2004         ign = net_generic(net, ip6gre_net_id);
2005
2006         if (nt->parms.collect_md) {
2007                 if (rtnl_dereference(ign->collect_md_tun))
2008                         return -EEXIST;
2009         } else {
2010                 if (ip6gre_tunnel_find(net, &nt->parms, dev->type))
2011                         return -EEXIST;
2012         }
2013
2014         err = ip6gre_newlink_common(src_net, dev, tb, data, extack);
2015         if (!err) {
2016                 ip6gre_tnl_link_config(nt, !tb[IFLA_MTU]);
2017                 ip6gre_tunnel_link_md(ign, nt);
2018                 ip6gre_tunnel_link(net_generic(net, ip6gre_net_id), nt);
2019         }
2020         return err;
2021 }
2022
2023 static struct ip6_tnl *
2024 ip6gre_changelink_common(struct net_device *dev, struct nlattr *tb[],
2025                          struct nlattr *data[], struct __ip6_tnl_parm *p_p,
2026                          struct netlink_ext_ack *extack)
2027 {
2028         struct ip6_tnl *t, *nt = netdev_priv(dev);
2029         struct net *net = nt->net;
2030         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
2031         struct ip_tunnel_encap ipencap;
2032
2033         if (dev == ign->fb_tunnel_dev)
2034                 return ERR_PTR(-EINVAL);
2035
2036         if (ip6gre_netlink_encap_parms(data, &ipencap)) {
2037                 int err = ip6_tnl_encap_setup(nt, &ipencap);
2038
2039                 if (err < 0)
2040                         return ERR_PTR(err);
2041         }
2042
2043         ip6gre_netlink_parms(data, p_p);
2044
2045         t = ip6gre_tunnel_locate(net, p_p, 0);
2046
2047         if (t) {
2048                 if (t->dev != dev)
2049                         return ERR_PTR(-EEXIST);
2050         } else {
2051                 t = nt;
2052         }
2053
2054         return t;
2055 }
2056
2057 static int ip6gre_changelink(struct net_device *dev, struct nlattr *tb[],
2058                              struct nlattr *data[],
2059                              struct netlink_ext_ack *extack)
2060 {
2061         struct ip6_tnl *t = netdev_priv(dev);
2062         struct ip6gre_net *ign = net_generic(t->net, ip6gre_net_id);
2063         struct __ip6_tnl_parm p;
2064
2065         t = ip6gre_changelink_common(dev, tb, data, &p, extack);
2066         if (IS_ERR(t))
2067                 return PTR_ERR(t);
2068
2069         ip6gre_tunnel_unlink_md(ign, t);
2070         ip6gre_tunnel_unlink(ign, t);
2071         ip6gre_tnl_change(t, &p, !tb[IFLA_MTU]);
2072         ip6gre_tunnel_link_md(ign, t);
2073         ip6gre_tunnel_link(ign, t);
2074         return 0;
2075 }
2076
2077 static void ip6gre_dellink(struct net_device *dev, struct list_head *head)
2078 {
2079         struct net *net = dev_net(dev);
2080         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
2081
2082         if (dev != ign->fb_tunnel_dev)
2083                 unregister_netdevice_queue(dev, head);
2084 }
2085
2086 static size_t ip6gre_get_size(const struct net_device *dev)
2087 {
2088         return
2089                 /* IFLA_GRE_LINK */
2090                 nla_total_size(4) +
2091                 /* IFLA_GRE_IFLAGS */
2092                 nla_total_size(2) +
2093                 /* IFLA_GRE_OFLAGS */
2094                 nla_total_size(2) +
2095                 /* IFLA_GRE_IKEY */
2096                 nla_total_size(4) +
2097                 /* IFLA_GRE_OKEY */
2098                 nla_total_size(4) +
2099                 /* IFLA_GRE_LOCAL */
2100                 nla_total_size(sizeof(struct in6_addr)) +
2101                 /* IFLA_GRE_REMOTE */
2102                 nla_total_size(sizeof(struct in6_addr)) +
2103                 /* IFLA_GRE_TTL */
2104                 nla_total_size(1) +
2105                 /* IFLA_GRE_ENCAP_LIMIT */
2106                 nla_total_size(1) +
2107                 /* IFLA_GRE_FLOWINFO */
2108                 nla_total_size(4) +
2109                 /* IFLA_GRE_FLAGS */
2110                 nla_total_size(4) +
2111                 /* IFLA_GRE_ENCAP_TYPE */
2112                 nla_total_size(2) +
2113                 /* IFLA_GRE_ENCAP_FLAGS */
2114                 nla_total_size(2) +
2115                 /* IFLA_GRE_ENCAP_SPORT */
2116                 nla_total_size(2) +
2117                 /* IFLA_GRE_ENCAP_DPORT */
2118                 nla_total_size(2) +
2119                 /* IFLA_GRE_COLLECT_METADATA */
2120                 nla_total_size(0) +
2121                 /* IFLA_GRE_FWMARK */
2122                 nla_total_size(4) +
2123                 /* IFLA_GRE_ERSPAN_INDEX */
2124                 nla_total_size(4) +
2125                 0;
2126 }
2127
2128 static int ip6gre_fill_info(struct sk_buff *skb, const struct net_device *dev)
2129 {
2130         struct ip6_tnl *t = netdev_priv(dev);
2131         struct __ip6_tnl_parm *p = &t->parms;
2132         __be16 o_flags = p->o_flags;
2133
2134         if (p->erspan_ver == 1 || p->erspan_ver == 2) {
2135                 if (!p->collect_md)
2136                         o_flags |= TUNNEL_KEY;
2137
2138                 if (nla_put_u8(skb, IFLA_GRE_ERSPAN_VER, p->erspan_ver))
2139                         goto nla_put_failure;
2140
2141                 if (p->erspan_ver == 1) {
2142                         if (nla_put_u32(skb, IFLA_GRE_ERSPAN_INDEX, p->index))
2143                                 goto nla_put_failure;
2144                 } else {
2145                         if (nla_put_u8(skb, IFLA_GRE_ERSPAN_DIR, p->dir))
2146                                 goto nla_put_failure;
2147                         if (nla_put_u16(skb, IFLA_GRE_ERSPAN_HWID, p->hwid))
2148                                 goto nla_put_failure;
2149                 }
2150         }
2151
2152         if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) ||
2153             nla_put_be16(skb, IFLA_GRE_IFLAGS,
2154                          gre_tnl_flags_to_gre_flags(p->i_flags)) ||
2155             nla_put_be16(skb, IFLA_GRE_OFLAGS,
2156                          gre_tnl_flags_to_gre_flags(o_flags)) ||
2157             nla_put_be32(skb, IFLA_GRE_IKEY, p->i_key) ||
2158             nla_put_be32(skb, IFLA_GRE_OKEY, p->o_key) ||
2159             nla_put_in6_addr(skb, IFLA_GRE_LOCAL, &p->laddr) ||
2160             nla_put_in6_addr(skb, IFLA_GRE_REMOTE, &p->raddr) ||
2161             nla_put_u8(skb, IFLA_GRE_TTL, p->hop_limit) ||
2162             nla_put_u8(skb, IFLA_GRE_ENCAP_LIMIT, p->encap_limit) ||
2163             nla_put_be32(skb, IFLA_GRE_FLOWINFO, p->flowinfo) ||
2164             nla_put_u32(skb, IFLA_GRE_FLAGS, p->flags) ||
2165             nla_put_u32(skb, IFLA_GRE_FWMARK, p->fwmark))
2166                 goto nla_put_failure;
2167
2168         if (nla_put_u16(skb, IFLA_GRE_ENCAP_TYPE,
2169                         t->encap.type) ||
2170             nla_put_be16(skb, IFLA_GRE_ENCAP_SPORT,
2171                          t->encap.sport) ||
2172             nla_put_be16(skb, IFLA_GRE_ENCAP_DPORT,
2173                          t->encap.dport) ||
2174             nla_put_u16(skb, IFLA_GRE_ENCAP_FLAGS,
2175                         t->encap.flags))
2176                 goto nla_put_failure;
2177
2178         if (p->collect_md) {
2179                 if (nla_put_flag(skb, IFLA_GRE_COLLECT_METADATA))
2180                         goto nla_put_failure;
2181         }
2182
2183         return 0;
2184
2185 nla_put_failure:
2186         return -EMSGSIZE;
2187 }
2188
2189 static const struct nla_policy ip6gre_policy[IFLA_GRE_MAX + 1] = {
2190         [IFLA_GRE_LINK]        = { .type = NLA_U32 },
2191         [IFLA_GRE_IFLAGS]      = { .type = NLA_U16 },
2192         [IFLA_GRE_OFLAGS]      = { .type = NLA_U16 },
2193         [IFLA_GRE_IKEY]        = { .type = NLA_U32 },
2194         [IFLA_GRE_OKEY]        = { .type = NLA_U32 },
2195         [IFLA_GRE_LOCAL]       = { .len = sizeof_field(struct ipv6hdr, saddr) },
2196         [IFLA_GRE_REMOTE]      = { .len = sizeof_field(struct ipv6hdr, daddr) },
2197         [IFLA_GRE_TTL]         = { .type = NLA_U8 },
2198         [IFLA_GRE_ENCAP_LIMIT] = { .type = NLA_U8 },
2199         [IFLA_GRE_FLOWINFO]    = { .type = NLA_U32 },
2200         [IFLA_GRE_FLAGS]       = { .type = NLA_U32 },
2201         [IFLA_GRE_ENCAP_TYPE]   = { .type = NLA_U16 },
2202         [IFLA_GRE_ENCAP_FLAGS]  = { .type = NLA_U16 },
2203         [IFLA_GRE_ENCAP_SPORT]  = { .type = NLA_U16 },
2204         [IFLA_GRE_ENCAP_DPORT]  = { .type = NLA_U16 },
2205         [IFLA_GRE_COLLECT_METADATA] = { .type = NLA_FLAG },
2206         [IFLA_GRE_FWMARK]       = { .type = NLA_U32 },
2207         [IFLA_GRE_ERSPAN_INDEX] = { .type = NLA_U32 },
2208         [IFLA_GRE_ERSPAN_VER]   = { .type = NLA_U8 },
2209         [IFLA_GRE_ERSPAN_DIR]   = { .type = NLA_U8 },
2210         [IFLA_GRE_ERSPAN_HWID]  = { .type = NLA_U16 },
2211 };
2212
2213 static void ip6erspan_tap_setup(struct net_device *dev)
2214 {
2215         ether_setup(dev);
2216
2217         dev->max_mtu = 0;
2218         dev->netdev_ops = &ip6erspan_netdev_ops;
2219         dev->needs_free_netdev = true;
2220         dev->priv_destructor = ip6gre_dev_free;
2221
2222         dev->priv_flags &= ~IFF_TX_SKB_SHARING;
2223         dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
2224         netif_keep_dst(dev);
2225 }
2226
2227 static int ip6erspan_newlink(struct net *src_net, struct net_device *dev,
2228                              struct nlattr *tb[], struct nlattr *data[],
2229                              struct netlink_ext_ack *extack)
2230 {
2231         struct ip6_tnl *nt = netdev_priv(dev);
2232         struct net *net = dev_net(dev);
2233         struct ip6gre_net *ign;
2234         int err;
2235
2236         ip6gre_netlink_parms(data, &nt->parms);
2237         ip6erspan_set_version(data, &nt->parms);
2238         ign = net_generic(net, ip6gre_net_id);
2239
2240         if (nt->parms.collect_md) {
2241                 if (rtnl_dereference(ign->collect_md_tun_erspan))
2242                         return -EEXIST;
2243         } else {
2244                 if (ip6gre_tunnel_find(net, &nt->parms, dev->type))
2245                         return -EEXIST;
2246         }
2247
2248         err = ip6gre_newlink_common(src_net, dev, tb, data, extack);
2249         if (!err) {
2250                 ip6erspan_tnl_link_config(nt, !tb[IFLA_MTU]);
2251                 ip6erspan_tunnel_link_md(ign, nt);
2252                 ip6gre_tunnel_link(net_generic(net, ip6gre_net_id), nt);
2253         }
2254         return err;
2255 }
2256
2257 static void ip6erspan_tnl_link_config(struct ip6_tnl *t, int set_mtu)
2258 {
2259         ip6gre_tnl_link_config_common(t);
2260         ip6gre_tnl_link_config_route(t, set_mtu, ip6erspan_calc_hlen(t));
2261 }
2262
2263 static int ip6erspan_tnl_change(struct ip6_tnl *t,
2264                                 const struct __ip6_tnl_parm *p, int set_mtu)
2265 {
2266         ip6gre_tnl_copy_tnl_parm(t, p);
2267         ip6erspan_tnl_link_config(t, set_mtu);
2268         return 0;
2269 }
2270
2271 static int ip6erspan_changelink(struct net_device *dev, struct nlattr *tb[],
2272                                 struct nlattr *data[],
2273                                 struct netlink_ext_ack *extack)
2274 {
2275         struct ip6gre_net *ign = net_generic(dev_net(dev), ip6gre_net_id);
2276         struct __ip6_tnl_parm p;
2277         struct ip6_tnl *t;
2278
2279         t = ip6gre_changelink_common(dev, tb, data, &p, extack);
2280         if (IS_ERR(t))
2281                 return PTR_ERR(t);
2282
2283         ip6erspan_set_version(data, &p);
2284         ip6gre_tunnel_unlink_md(ign, t);
2285         ip6gre_tunnel_unlink(ign, t);
2286         ip6erspan_tnl_change(t, &p, !tb[IFLA_MTU]);
2287         ip6erspan_tunnel_link_md(ign, t);
2288         ip6gre_tunnel_link(ign, t);
2289         return 0;
2290 }
2291
2292 static struct rtnl_link_ops ip6gre_link_ops __read_mostly = {
2293         .kind           = "ip6gre",
2294         .maxtype        = IFLA_GRE_MAX,
2295         .policy         = ip6gre_policy,
2296         .priv_size      = sizeof(struct ip6_tnl),
2297         .setup          = ip6gre_tunnel_setup,
2298         .validate       = ip6gre_tunnel_validate,
2299         .newlink        = ip6gre_newlink,
2300         .changelink     = ip6gre_changelink,
2301         .dellink        = ip6gre_dellink,
2302         .get_size       = ip6gre_get_size,
2303         .fill_info      = ip6gre_fill_info,
2304         .get_link_net   = ip6_tnl_get_link_net,
2305 };
2306
2307 static struct rtnl_link_ops ip6gre_tap_ops __read_mostly = {
2308         .kind           = "ip6gretap",
2309         .maxtype        = IFLA_GRE_MAX,
2310         .policy         = ip6gre_policy,
2311         .priv_size      = sizeof(struct ip6_tnl),
2312         .setup          = ip6gre_tap_setup,
2313         .validate       = ip6gre_tap_validate,
2314         .newlink        = ip6gre_newlink,
2315         .changelink     = ip6gre_changelink,
2316         .get_size       = ip6gre_get_size,
2317         .fill_info      = ip6gre_fill_info,
2318         .get_link_net   = ip6_tnl_get_link_net,
2319 };
2320
2321 static struct rtnl_link_ops ip6erspan_tap_ops __read_mostly = {
2322         .kind           = "ip6erspan",
2323         .maxtype        = IFLA_GRE_MAX,
2324         .policy         = ip6gre_policy,
2325         .priv_size      = sizeof(struct ip6_tnl),
2326         .setup          = ip6erspan_tap_setup,
2327         .validate       = ip6erspan_tap_validate,
2328         .newlink        = ip6erspan_newlink,
2329         .changelink     = ip6erspan_changelink,
2330         .get_size       = ip6gre_get_size,
2331         .fill_info      = ip6gre_fill_info,
2332         .get_link_net   = ip6_tnl_get_link_net,
2333 };
2334
2335 /*
2336  *      And now the modules code and kernel interface.
2337  */
2338
2339 static int __init ip6gre_init(void)
2340 {
2341         int err;
2342
2343         pr_info("GRE over IPv6 tunneling driver\n");
2344
2345         err = register_pernet_device(&ip6gre_net_ops);
2346         if (err < 0)
2347                 return err;
2348
2349         err = inet6_add_protocol(&ip6gre_protocol, IPPROTO_GRE);
2350         if (err < 0) {
2351                 pr_info("%s: can't add protocol\n", __func__);
2352                 goto add_proto_failed;
2353         }
2354
2355         err = rtnl_link_register(&ip6gre_link_ops);
2356         if (err < 0)
2357                 goto rtnl_link_failed;
2358
2359         err = rtnl_link_register(&ip6gre_tap_ops);
2360         if (err < 0)
2361                 goto tap_ops_failed;
2362
2363         err = rtnl_link_register(&ip6erspan_tap_ops);
2364         if (err < 0)
2365                 goto erspan_link_failed;
2366
2367 out:
2368         return err;
2369
2370 erspan_link_failed:
2371         rtnl_link_unregister(&ip6gre_tap_ops);
2372 tap_ops_failed:
2373         rtnl_link_unregister(&ip6gre_link_ops);
2374 rtnl_link_failed:
2375         inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE);
2376 add_proto_failed:
2377         unregister_pernet_device(&ip6gre_net_ops);
2378         goto out;
2379 }
2380
2381 static void __exit ip6gre_fini(void)
2382 {
2383         rtnl_link_unregister(&ip6gre_tap_ops);
2384         rtnl_link_unregister(&ip6gre_link_ops);
2385         rtnl_link_unregister(&ip6erspan_tap_ops);
2386         inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE);
2387         unregister_pernet_device(&ip6gre_net_ops);
2388 }
2389
2390 module_init(ip6gre_init);
2391 module_exit(ip6gre_fini);
2392 MODULE_LICENSE("GPL");
2393 MODULE_AUTHOR("D. Kozlov (xeb@mail.ru)");
2394 MODULE_DESCRIPTION("GRE over IPv6 tunneling device");
2395 MODULE_ALIAS_RTNL_LINK("ip6gre");
2396 MODULE_ALIAS_RTNL_LINK("ip6gretap");
2397 MODULE_ALIAS_RTNL_LINK("ip6erspan");
2398 MODULE_ALIAS_NETDEV("ip6gre0");