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 ([email protected])
   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_track(dev, &t->dev_tracker);
 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_track(dev, &t->dev_tracker);
 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                 fl6->fl6_gre_key = tunnel_id_to_key32(key->tun_id);
 759
 760                 dsfield = key->tos;
 761                 flags = key->tun_flags &
 762                         (TUNNEL_CSUM | TUNNEL_KEY | TUNNEL_SEQ);
 763                 tunnel->tun_hlen = gre_calc_hlen(flags);
 764
 765                 gre_build_header(skb, tunnel->tun_hlen,
 766                                  flags, protocol,
 767                                  tunnel_id_to_key32(tun_info->key.tun_id),
 768                                  (flags & TUNNEL_SEQ) ? htonl(tunnel->o_seqno++)
 769                                                       : 0);
 770
 771         } else {
 772                 if (tunnel->parms.o_flags & TUNNEL_SEQ)
 773                         tunnel->o_seqno++;
 774
 775                 gre_build_header(skb, tunnel->tun_hlen, tunnel->parms.o_flags,
 776                                  protocol, tunnel->parms.o_key,
 777                                  htonl(tunnel->o_seqno));
 778         }
 779
 780         return ip6_tnl_xmit(skb, dev, dsfield, fl6, encap_limit, pmtu,
 781                             NEXTHDR_GRE);
 782 }
 783
 784 static inline int ip6gre_xmit_ipv4(struct sk_buff *skb, struct net_device *dev)
 785 {
 786         struct ip6_tnl *t = netdev_priv(dev);
 787         int encap_limit = -1;
 788         struct flowi6 fl6;
 789         __u8 dsfield = 0;
 790         __u32 mtu;
 791         int err;
 792
 793         memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
 794
 795         if (!t->parms.collect_md)
 796                 prepare_ip6gre_xmit_ipv4(skb, dev, &fl6,
 797                                          &dsfield, &encap_limit);
 798
 799         err = gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM));
 800         if (err)
 801                 return -1;
 802
 803         err = __gre6_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu,
 804                           skb->protocol);
 805         if (err != 0) {
 806                 /* XXX: send ICMP error even if DF is not set. */
 807                 if (err == -EMSGSIZE)
 808                         icmp_ndo_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
 809                                       htonl(mtu));
 810                 return -1;
 811         }
 812
 813         return 0;
 814 }
 815
 816 static inline int ip6gre_xmit_ipv6(struct sk_buff *skb, struct net_device *dev)
 817 {
 818         struct ip6_tnl *t = netdev_priv(dev);
 819         struct ipv6hdr *ipv6h = ipv6_hdr(skb);
 820         int encap_limit = -1;
 821         struct flowi6 fl6;
 822         __u8 dsfield = 0;
 823         __u32 mtu;
 824         int err;
 825
 826         if (ipv6_addr_equal(&t->parms.raddr, &ipv6h->saddr))
 827                 return -1;
 828
 829         if (!t->parms.collect_md &&
 830             prepare_ip6gre_xmit_ipv6(skb, dev, &fl6, &dsfield, &encap_limit))
 831                 return -1;
 832
 833         if (gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM)))
 834                 return -1;
 835
 836         err = __gre6_xmit(skb, dev, dsfield, &fl6, encap_limit,
 837                           &mtu, skb->protocol);
 838         if (err != 0) {
 839                 if (err == -EMSGSIZE)
 840                         icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
 841                 return -1;
 842         }
 843
 844         return 0;
 845 }
 846
 847 /**
 848  * ip6gre_tnl_addr_conflict - compare packet addresses to tunnel's own
 849  *   @t: the outgoing tunnel device
 850  *   @hdr: IPv6 header from the incoming packet
 851  *
 852  * Description:
 853  *   Avoid trivial tunneling loop by checking that tunnel exit-point
 854  *   doesn't match source of incoming packet.
 855  *
 856  * Return:
 857  *   1 if conflict,
 858  *   0 else
 859  **/
 860
 861 static inline bool ip6gre_tnl_addr_conflict(const struct ip6_tnl *t,
 862         const struct ipv6hdr *hdr)
 863 {
 864         return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr);
 865 }
 866
 867 static int ip6gre_xmit_other(struct sk_buff *skb, struct net_device *dev)
 868 {
 869         struct ip6_tnl *t = netdev_priv(dev);
 870         int encap_limit = -1;
 871         struct flowi6 fl6;
 872         __u32 mtu;
 873         int err;
 874
 875         if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
 876                 encap_limit = t->parms.encap_limit;
 877
 878         if (!t->parms.collect_md)
 879                 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
 880
 881         err = gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM));
 882         if (err)
 883                 return err;
 884
 885         err = __gre6_xmit(skb, dev, 0, &fl6, encap_limit, &mtu, skb->protocol);
 886
 887         return err;
 888 }
 889
 890 static netdev_tx_t ip6gre_tunnel_xmit(struct sk_buff *skb,
 891         struct net_device *dev)
 892 {
 893         struct ip6_tnl *t = netdev_priv(dev);
 894         struct net_device_stats *stats = &t->dev->stats;
 895         int ret;
 896
 897         if (!pskb_inet_may_pull(skb))
 898                 goto tx_err;
 899
 900         if (!ip6_tnl_xmit_ctl(t, &t->parms.laddr, &t->parms.raddr))
 901                 goto tx_err;
 902
 903         switch (skb->protocol) {
 904         case htons(ETH_P_IP):
 905                 ret = ip6gre_xmit_ipv4(skb, dev);
 906                 break;
 907         case htons(ETH_P_IPV6):
 908                 ret = ip6gre_xmit_ipv6(skb, dev);
 909                 break;
 910         default:
 911                 ret = ip6gre_xmit_other(skb, dev);
 912                 break;
 913         }
 914
 915         if (ret < 0)
 916                 goto tx_err;
 917
 918         return NETDEV_TX_OK;
 919
 920 tx_err:
 921         if (!t->parms.collect_md || !IS_ERR(skb_tunnel_info_txcheck(skb)))
 922                 stats->tx_errors++;
 923         stats->tx_dropped++;
 924         kfree_skb(skb);
 925         return NETDEV_TX_OK;
 926 }
 927
 928 static netdev_tx_t ip6erspan_tunnel_xmit(struct sk_buff *skb,
 929                                          struct net_device *dev)
 930 {
 931         struct ip_tunnel_info *tun_info = NULL;
 932         struct ip6_tnl *t = netdev_priv(dev);
 933         struct dst_entry *dst = skb_dst(skb);
 934         struct net_device_stats *stats;
 935         bool truncate = false;
 936         int encap_limit = -1;
 937         __u8 dsfield = false;
 938         struct flowi6 fl6;
 939         int err = -EINVAL;
 940         __be16 proto;
 941         __u32 mtu;
 942         int nhoff;
 943         int thoff;
 944
 945         if (!pskb_inet_may_pull(skb))
 946                 goto tx_err;
 947
 948         if (!ip6_tnl_xmit_ctl(t, &t->parms.laddr, &t->parms.raddr))
 949                 goto tx_err;
 950
 951         if (gre_handle_offloads(skb, false))
 952                 goto tx_err;
 953
 954         if (skb->len > dev->mtu + dev->hard_header_len) {
 955                 pskb_trim(skb, dev->mtu + dev->hard_header_len);
 956                 truncate = true;
 957         }
 958
 959         nhoff = skb_network_header(skb) - skb_mac_header(skb);
 960         if (skb->protocol == htons(ETH_P_IP) &&
 961             (ntohs(ip_hdr(skb)->tot_len) > skb->len - nhoff))
 962                 truncate = true;
 963
 964         thoff = skb_transport_header(skb) - skb_mac_header(skb);
 965         if (skb->protocol == htons(ETH_P_IPV6) &&
 966             (ntohs(ipv6_hdr(skb)->payload_len) > skb->len - thoff))
 967                 truncate = true;
 968
 969         if (skb_cow_head(skb, dev->needed_headroom ?: t->hlen))
 970                 goto tx_err;
 971
 972         t->parms.o_flags &= ~TUNNEL_KEY;
 973         IPCB(skb)->flags = 0;
 974
 975         /* For collect_md mode, derive fl6 from the tunnel key,
 976          * for native mode, call prepare_ip6gre_xmit_{ipv4,ipv6}.
 977          */
 978         if (t->parms.collect_md) {
 979                 const struct ip_tunnel_key *key;
 980                 struct erspan_metadata *md;
 981                 __be32 tun_id;
 982
 983                 tun_info = skb_tunnel_info_txcheck(skb);
 984                 if (IS_ERR(tun_info) ||
 985                     unlikely(ip_tunnel_info_af(tun_info) != AF_INET6))
 986                         goto tx_err;
 987
 988                 key = &tun_info->key;
 989                 memset(&fl6, 0, sizeof(fl6));
 990                 fl6.flowi6_proto = IPPROTO_GRE;
 991                 fl6.daddr = key->u.ipv6.dst;
 992                 fl6.flowlabel = key->label;
 993                 fl6.flowi6_uid = sock_net_uid(dev_net(dev), NULL);
 994                 fl6.fl6_gre_key = tunnel_id_to_key32(key->tun_id);
 995
 996                 dsfield = key->tos;
 997                 if (!(tun_info->key.tun_flags & TUNNEL_ERSPAN_OPT))
 998                         goto tx_err;
 999                 if (tun_info->options_len < sizeof(*md))
1000                         goto tx_err;
1001                 md = ip_tunnel_info_opts(tun_info);
1002
1003                 tun_id = tunnel_id_to_key32(key->tun_id);
1004                 if (md->version == 1) {
1005                         erspan_build_header(skb,
1006                                             ntohl(tun_id),
1007                                             ntohl(md->u.index), truncate,
1008                                             false);
1009                 } else if (md->version == 2) {
1010                         erspan_build_header_v2(skb,
1011                                                ntohl(tun_id),
1012                                                md->u.md2.dir,
1013                                                get_hwid(&md->u.md2),
1014                                                truncate, false);
1015                 } else {
1016                         goto tx_err;
1017                 }
1018         } else {
1019                 switch (skb->protocol) {
1020                 case htons(ETH_P_IP):
1021                         memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
1022                         prepare_ip6gre_xmit_ipv4(skb, dev, &fl6,
1023                                                  &dsfield, &encap_limit);
1024                         break;
1025                 case htons(ETH_P_IPV6):
1026                         if (ipv6_addr_equal(&t->parms.raddr, &ipv6_hdr(skb)->saddr))
1027                                 goto tx_err;
1028                         if (prepare_ip6gre_xmit_ipv6(skb, dev, &fl6,
1029                                                      &dsfield, &encap_limit))
1030                                 goto tx_err;
1031                         break;
1032                 default:
1033                         memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
1034                         break;
1035                 }
1036
1037                 if (t->parms.erspan_ver == 1)
1038                         erspan_build_header(skb, ntohl(t->parms.o_key),
1039                                             t->parms.index,
1040                                             truncate, false);
1041                 else if (t->parms.erspan_ver == 2)
1042                         erspan_build_header_v2(skb, ntohl(t->parms.o_key),
1043                                                t->parms.dir,
1044                                                t->parms.hwid,
1045                                                truncate, false);
1046                 else
1047                         goto tx_err;
1048
1049                 fl6.daddr = t->parms.raddr;
1050         }
1051
1052         /* Push GRE header. */
1053         proto = (t->parms.erspan_ver == 1) ? htons(ETH_P_ERSPAN)
1054                                            : htons(ETH_P_ERSPAN2);
1055         gre_build_header(skb, 8, TUNNEL_SEQ, proto, 0, htonl(t->o_seqno++));
1056
1057         /* TooBig packet may have updated dst->dev's mtu */
1058         if (!t->parms.collect_md && dst && dst_mtu(dst) > dst->dev->mtu)
1059                 dst->ops->update_pmtu(dst, NULL, skb, dst->dev->mtu, false);
1060
1061         err = ip6_tnl_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu,
1062                            NEXTHDR_GRE);
1063         if (err != 0) {
1064                 /* XXX: send ICMP error even if DF is not set. */
1065                 if (err == -EMSGSIZE) {
1066                         if (skb->protocol == htons(ETH_P_IP))
1067                                 icmp_ndo_send(skb, ICMP_DEST_UNREACH,
1068                                               ICMP_FRAG_NEEDED, htonl(mtu));
1069                         else
1070                                 icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
1071                 }
1072
1073                 goto tx_err;
1074         }
1075         return NETDEV_TX_OK;
1076
1077 tx_err:
1078         stats = &t->dev->stats;
1079         if (!IS_ERR(tun_info))
1080                 stats->tx_errors++;
1081         stats->tx_dropped++;
1082         kfree_skb(skb);
1083         return NETDEV_TX_OK;
1084 }
1085
1086 static void ip6gre_tnl_link_config_common(struct ip6_tnl *t)
1087 {
1088         struct net_device *dev = t->dev;
1089         struct __ip6_tnl_parm *p = &t->parms;
1090         struct flowi6 *fl6 = &t->fl.u.ip6;
1091
1092         if (dev->type != ARPHRD_ETHER) {
1093                 __dev_addr_set(dev, &p->laddr, sizeof(struct in6_addr));
1094                 memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr));
1095         }
1096
1097         /* Set up flowi template */
1098         fl6->saddr = p->laddr;
1099         fl6->daddr = p->raddr;
1100         fl6->flowi6_oif = p->link;
1101         fl6->flowlabel = 0;
1102         fl6->flowi6_proto = IPPROTO_GRE;
1103         fl6->fl6_gre_key = t->parms.o_key;
1104
1105         if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS))
1106                 fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo;
1107         if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL))
1108                 fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo;
1109
1110         p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET);
1111         p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr);
1112
1113         if (p->flags&IP6_TNL_F_CAP_XMIT &&
1114                         p->flags&IP6_TNL_F_CAP_RCV && dev->type != ARPHRD_ETHER)
1115                 dev->flags |= IFF_POINTOPOINT;
1116         else
1117                 dev->flags &= ~IFF_POINTOPOINT;
1118 }
1119
1120 static void ip6gre_tnl_link_config_route(struct ip6_tnl *t, int set_mtu,
1121                                          int t_hlen)
1122 {
1123         const struct __ip6_tnl_parm *p = &t->parms;
1124         struct net_device *dev = t->dev;
1125
1126         if (p->flags & IP6_TNL_F_CAP_XMIT) {
1127                 int strict = (ipv6_addr_type(&p->raddr) &
1128                               (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL));
1129
1130                 struct rt6_info *rt = rt6_lookup(t->net,
1131                                                  &p->raddr, &p->laddr,
1132                                                  p->link, NULL, strict);
1133
1134                 if (!rt)
1135                         return;
1136
1137                 if (rt->dst.dev) {
1138                         unsigned short dst_len = rt->dst.dev->hard_header_len +
1139                                                  t_hlen;
1140
1141                         if (t->dev->header_ops)
1142                                 dev->hard_header_len = dst_len;
1143                         else
1144                                 dev->needed_headroom = dst_len;
1145
1146                         if (set_mtu) {
1147                                 dev->mtu = rt->dst.dev->mtu - t_hlen;
1148                                 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1149                                         dev->mtu -= 8;
1150                                 if (dev->type == ARPHRD_ETHER)
1151                                         dev->mtu -= ETH_HLEN;
1152
1153                                 if (dev->mtu < IPV6_MIN_MTU)
1154                                         dev->mtu = IPV6_MIN_MTU;
1155                         }
1156                 }
1157                 ip6_rt_put(rt);
1158         }
1159 }
1160
1161 static int ip6gre_calc_hlen(struct ip6_tnl *tunnel)
1162 {
1163         int t_hlen;
1164
1165         tunnel->tun_hlen = gre_calc_hlen(tunnel->parms.o_flags);
1166         tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen;
1167
1168         t_hlen = tunnel->hlen + sizeof(struct ipv6hdr);
1169
1170         if (tunnel->dev->header_ops)
1171                 tunnel->dev->hard_header_len = LL_MAX_HEADER + t_hlen;
1172         else
1173                 tunnel->dev->needed_headroom = LL_MAX_HEADER + t_hlen;
1174
1175         return t_hlen;
1176 }
1177
1178 static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu)
1179 {
1180         ip6gre_tnl_link_config_common(t);
1181         ip6gre_tnl_link_config_route(t, set_mtu, ip6gre_calc_hlen(t));
1182 }
1183
1184 static void ip6gre_tnl_copy_tnl_parm(struct ip6_tnl *t,
1185                                      const struct __ip6_tnl_parm *p)
1186 {
1187         t->parms.laddr = p->laddr;
1188         t->parms.raddr = p->raddr;
1189         t->parms.flags = p->flags;
1190         t->parms.hop_limit = p->hop_limit;
1191         t->parms.encap_limit = p->encap_limit;
1192         t->parms.flowinfo = p->flowinfo;
1193         t->parms.link = p->link;
1194         t->parms.proto = p->proto;
1195         t->parms.i_key = p->i_key;
1196         t->parms.o_key = p->o_key;
1197         t->parms.i_flags = p->i_flags;
1198         t->parms.o_flags = p->o_flags;
1199         t->parms.fwmark = p->fwmark;
1200         t->parms.erspan_ver = p->erspan_ver;
1201         t->parms.index = p->index;
1202         t->parms.dir = p->dir;
1203         t->parms.hwid = p->hwid;
1204         dst_cache_reset(&t->dst_cache);
1205 }
1206
1207 static int ip6gre_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p,
1208                              int set_mtu)
1209 {
1210         ip6gre_tnl_copy_tnl_parm(t, p);
1211         ip6gre_tnl_link_config(t, set_mtu);
1212         return 0;
1213 }
1214
1215 static void ip6gre_tnl_parm_from_user(struct __ip6_tnl_parm *p,
1216         const struct ip6_tnl_parm2 *u)
1217 {
1218         p->laddr = u->laddr;
1219         p->raddr = u->raddr;
1220         p->flags = u->flags;
1221         p->hop_limit = u->hop_limit;
1222         p->encap_limit = u->encap_limit;
1223         p->flowinfo = u->flowinfo;
1224         p->link = u->link;
1225         p->i_key = u->i_key;
1226         p->o_key = u->o_key;
1227         p->i_flags = gre_flags_to_tnl_flags(u->i_flags);
1228         p->o_flags = gre_flags_to_tnl_flags(u->o_flags);
1229         memcpy(p->name, u->name, sizeof(u->name));
1230 }
1231
1232 static void ip6gre_tnl_parm_to_user(struct ip6_tnl_parm2 *u,
1233         const struct __ip6_tnl_parm *p)
1234 {
1235         u->proto = IPPROTO_GRE;
1236         u->laddr = p->laddr;
1237         u->raddr = p->raddr;
1238         u->flags = p->flags;
1239         u->hop_limit = p->hop_limit;
1240         u->encap_limit = p->encap_limit;
1241         u->flowinfo = p->flowinfo;
1242         u->link = p->link;
1243         u->i_key = p->i_key;
1244         u->o_key = p->o_key;
1245         u->i_flags = gre_tnl_flags_to_gre_flags(p->i_flags);
1246         u->o_flags = gre_tnl_flags_to_gre_flags(p->o_flags);
1247         memcpy(u->name, p->name, sizeof(u->name));
1248 }
1249
1250 static int ip6gre_tunnel_siocdevprivate(struct net_device *dev,
1251                                         struct ifreq *ifr, void __user *data,
1252                                         int cmd)
1253 {
1254         int err = 0;
1255         struct ip6_tnl_parm2 p;
1256         struct __ip6_tnl_parm p1;
1257         struct ip6_tnl *t = netdev_priv(dev);
1258         struct net *net = t->net;
1259         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1260
1261         memset(&p1, 0, sizeof(p1));
1262
1263         switch (cmd) {
1264         case SIOCGETTUNNEL:
1265                 if (dev == ign->fb_tunnel_dev) {
1266                         if (copy_from_user(&p, data, sizeof(p))) {
1267                                 err = -EFAULT;
1268                                 break;
1269                         }
1270                         ip6gre_tnl_parm_from_user(&p1, &p);
1271                         t = ip6gre_tunnel_locate(net, &p1, 0);
1272                         if (!t)
1273                                 t = netdev_priv(dev);
1274                 }
1275                 memset(&p, 0, sizeof(p));
1276                 ip6gre_tnl_parm_to_user(&p, &t->parms);
1277                 if (copy_to_user(data, &p, sizeof(p)))
1278                         err = -EFAULT;
1279                 break;
1280
1281         case SIOCADDTUNNEL:
1282         case SIOCCHGTUNNEL:
1283                 err = -EPERM;
1284                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1285                         goto done;
1286
1287                 err = -EFAULT;
1288                 if (copy_from_user(&p, data, sizeof(p)))
1289                         goto done;
1290
1291                 err = -EINVAL;
1292                 if ((p.i_flags|p.o_flags)&(GRE_VERSION|GRE_ROUTING))
1293                         goto done;
1294
1295                 if (!(p.i_flags&GRE_KEY))
1296                         p.i_key = 0;
1297                 if (!(p.o_flags&GRE_KEY))
1298                         p.o_key = 0;
1299
1300                 ip6gre_tnl_parm_from_user(&p1, &p);
1301                 t = ip6gre_tunnel_locate(net, &p1, cmd == SIOCADDTUNNEL);
1302
1303                 if (dev != ign->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
1304                         if (t) {
1305                                 if (t->dev != dev) {
1306                                         err = -EEXIST;
1307                                         break;
1308                                 }
1309                         } else {
1310                                 t = netdev_priv(dev);
1311
1312                                 ip6gre_tunnel_unlink(ign, t);
1313                                 synchronize_net();
1314                                 ip6gre_tnl_change(t, &p1, 1);
1315                                 ip6gre_tunnel_link(ign, t);
1316                                 netdev_state_change(dev);
1317                         }
1318                 }
1319
1320                 if (t) {
1321                         err = 0;
1322
1323                         memset(&p, 0, sizeof(p));
1324                         ip6gre_tnl_parm_to_user(&p, &t->parms);
1325                         if (copy_to_user(data, &p, sizeof(p)))
1326                                 err = -EFAULT;
1327                 } else
1328                         err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
1329                 break;
1330
1331         case SIOCDELTUNNEL:
1332                 err = -EPERM;
1333                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1334                         goto done;
1335
1336                 if (dev == ign->fb_tunnel_dev) {
1337                         err = -EFAULT;
1338                         if (copy_from_user(&p, data, sizeof(p)))
1339                                 goto done;
1340                         err = -ENOENT;
1341                         ip6gre_tnl_parm_from_user(&p1, &p);
1342                         t = ip6gre_tunnel_locate(net, &p1, 0);
1343                         if (!t)
1344                                 goto done;
1345                         err = -EPERM;
1346                         if (t == netdev_priv(ign->fb_tunnel_dev))
1347                                 goto done;
1348                         dev = t->dev;
1349                 }
1350                 unregister_netdevice(dev);
1351                 err = 0;
1352                 break;
1353
1354         default:
1355                 err = -EINVAL;
1356         }
1357
1358 done:
1359         return err;
1360 }
1361
1362 static int ip6gre_header(struct sk_buff *skb, struct net_device *dev,
1363                          unsigned short type, const void *daddr,
1364                          const void *saddr, unsigned int len)
1365 {
1366         struct ip6_tnl *t = netdev_priv(dev);
1367         struct ipv6hdr *ipv6h;
1368         __be16 *p;
1369
1370         ipv6h = skb_push(skb, t->hlen + sizeof(*ipv6h));
1371         ip6_flow_hdr(ipv6h, 0, ip6_make_flowlabel(dev_net(dev), skb,
1372                                                   t->fl.u.ip6.flowlabel,
1373                                                   true, &t->fl.u.ip6));
1374         ipv6h->hop_limit = t->parms.hop_limit;
1375         ipv6h->nexthdr = NEXTHDR_GRE;
1376         ipv6h->saddr = t->parms.laddr;
1377         ipv6h->daddr = t->parms.raddr;
1378
1379         p = (__be16 *)(ipv6h + 1);
1380         p[0] = t->parms.o_flags;
1381         p[1] = htons(type);
1382
1383         /*
1384          *      Set the source hardware address.
1385          */
1386
1387         if (saddr)
1388                 memcpy(&ipv6h->saddr, saddr, sizeof(struct in6_addr));
1389         if (daddr)
1390                 memcpy(&ipv6h->daddr, daddr, sizeof(struct in6_addr));
1391         if (!ipv6_addr_any(&ipv6h->daddr))
1392                 return t->hlen;
1393
1394         return -t->hlen;
1395 }
1396
1397 static const struct header_ops ip6gre_header_ops = {
1398         .create = ip6gre_header,
1399 };
1400
1401 static const struct net_device_ops ip6gre_netdev_ops = {
1402         .ndo_init               = ip6gre_tunnel_init,
1403         .ndo_uninit             = ip6gre_tunnel_uninit,
1404         .ndo_start_xmit         = ip6gre_tunnel_xmit,
1405         .ndo_siocdevprivate     = ip6gre_tunnel_siocdevprivate,
1406         .ndo_change_mtu         = ip6_tnl_change_mtu,
1407         .ndo_get_stats64        = dev_get_tstats64,
1408         .ndo_get_iflink         = ip6_tnl_get_iflink,
1409 };
1410
1411 static void ip6gre_dev_free(struct net_device *dev)
1412 {
1413         struct ip6_tnl *t = netdev_priv(dev);
1414
1415         gro_cells_destroy(&t->gro_cells);
1416         dst_cache_destroy(&t->dst_cache);
1417         free_percpu(dev->tstats);
1418 }
1419
1420 static void ip6gre_tunnel_setup(struct net_device *dev)
1421 {
1422         dev->netdev_ops = &ip6gre_netdev_ops;
1423         dev->needs_free_netdev = true;
1424         dev->priv_destructor = ip6gre_dev_free;
1425
1426         dev->type = ARPHRD_IP6GRE;
1427
1428         dev->flags |= IFF_NOARP;
1429         dev->addr_len = sizeof(struct in6_addr);
1430         netif_keep_dst(dev);
1431         /* This perm addr will be used as interface identifier by IPv6 */
1432         dev->addr_assign_type = NET_ADDR_RANDOM;
1433         eth_random_addr(dev->perm_addr);
1434 }
1435
1436 #define GRE6_FEATURES (NETIF_F_SG |             \
1437                        NETIF_F_FRAGLIST |       \
1438                        NETIF_F_HIGHDMA |        \
1439                        NETIF_F_HW_CSUM)
1440
1441 static void ip6gre_tnl_init_features(struct net_device *dev)
1442 {
1443         struct ip6_tnl *nt = netdev_priv(dev);
1444
1445         dev->features           |= GRE6_FEATURES;
1446         dev->hw_features        |= GRE6_FEATURES;
1447
1448         if (!(nt->parms.o_flags & TUNNEL_SEQ)) {
1449                 /* TCP offload with GRE SEQ is not supported, nor
1450                  * can we support 2 levels of outer headers requiring
1451                  * an update.
1452                  */
1453                 if (!(nt->parms.o_flags & TUNNEL_CSUM) ||
1454                     nt->encap.type == TUNNEL_ENCAP_NONE) {
1455                         dev->features    |= NETIF_F_GSO_SOFTWARE;
1456                         dev->hw_features |= NETIF_F_GSO_SOFTWARE;
1457                 }
1458
1459                 /* Can use a lockless transmit, unless we generate
1460                  * output sequences
1461                  */
1462                 dev->features |= NETIF_F_LLTX;
1463         }
1464 }
1465
1466 static int ip6gre_tunnel_init_common(struct net_device *dev)
1467 {
1468         struct ip6_tnl *tunnel;
1469         int ret;
1470         int t_hlen;
1471
1472         tunnel = netdev_priv(dev);
1473
1474         tunnel->dev = dev;
1475         tunnel->net = dev_net(dev);
1476         strcpy(tunnel->parms.name, dev->name);
1477
1478         dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1479         if (!dev->tstats)
1480                 return -ENOMEM;
1481
1482         ret = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
1483         if (ret)
1484                 goto cleanup_alloc_pcpu_stats;
1485
1486         ret = gro_cells_init(&tunnel->gro_cells, dev);
1487         if (ret)
1488                 goto cleanup_dst_cache_init;
1489
1490         t_hlen = ip6gre_calc_hlen(tunnel);
1491         dev->mtu = ETH_DATA_LEN - t_hlen;
1492         if (dev->type == ARPHRD_ETHER)
1493                 dev->mtu -= ETH_HLEN;
1494         if (!(tunnel->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1495                 dev->mtu -= 8;
1496
1497         if (tunnel->parms.collect_md) {
1498                 netif_keep_dst(dev);
1499         }
1500         ip6gre_tnl_init_features(dev);
1501
1502         dev_hold_track(dev, &tunnel->dev_tracker, GFP_KERNEL);
1503         return 0;
1504
1505 cleanup_dst_cache_init:
1506         dst_cache_destroy(&tunnel->dst_cache);
1507 cleanup_alloc_pcpu_stats:
1508         free_percpu(dev->tstats);
1509         dev->tstats = NULL;
1510         return ret;
1511 }
1512
1513 static int ip6gre_tunnel_init(struct net_device *dev)
1514 {
1515         struct ip6_tnl *tunnel;
1516         int ret;
1517
1518         ret = ip6gre_tunnel_init_common(dev);
1519         if (ret)
1520                 return ret;
1521
1522         tunnel = netdev_priv(dev);
1523
1524         if (tunnel->parms.collect_md)
1525                 return 0;
1526
1527         __dev_addr_set(dev, &tunnel->parms.laddr, sizeof(struct in6_addr));
1528         memcpy(dev->broadcast, &tunnel->parms.raddr, sizeof(struct in6_addr));
1529
1530         if (ipv6_addr_any(&tunnel->parms.raddr))
1531                 dev->header_ops = &ip6gre_header_ops;
1532
1533         return 0;
1534 }
1535
1536 static void ip6gre_fb_tunnel_init(struct net_device *dev)
1537 {
1538         struct ip6_tnl *tunnel = netdev_priv(dev);
1539
1540         tunnel->dev = dev;
1541         tunnel->net = dev_net(dev);
1542         strcpy(tunnel->parms.name, dev->name);
1543
1544         tunnel->hlen            = sizeof(struct ipv6hdr) + 4;
1545 }
1546
1547 static struct inet6_protocol ip6gre_protocol __read_mostly = {
1548         .handler     = gre_rcv,
1549         .err_handler = ip6gre_err,
1550         .flags       = INET6_PROTO_FINAL,
1551 };
1552
1553 static void ip6gre_destroy_tunnels(struct net *net, struct list_head *head)
1554 {
1555         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1556         struct net_device *dev, *aux;
1557         int prio;
1558
1559         for_each_netdev_safe(net, dev, aux)
1560                 if (dev->rtnl_link_ops == &ip6gre_link_ops ||
1561                     dev->rtnl_link_ops == &ip6gre_tap_ops ||
1562                     dev->rtnl_link_ops == &ip6erspan_tap_ops)
1563                         unregister_netdevice_queue(dev, head);
1564
1565         for (prio = 0; prio < 4; prio++) {
1566                 int h;
1567                 for (h = 0; h < IP6_GRE_HASH_SIZE; h++) {
1568                         struct ip6_tnl *t;
1569
1570                         t = rtnl_dereference(ign->tunnels[prio][h]);
1571
1572                         while (t) {
1573                                 /* If dev is in the same netns, it has already
1574                                  * been added to the list by the previous loop.
1575                                  */
1576                                 if (!net_eq(dev_net(t->dev), net))
1577                                         unregister_netdevice_queue(t->dev,
1578                                                                    head);
1579                                 t = rtnl_dereference(t->next);
1580                         }
1581                 }
1582         }
1583 }
1584
1585 static int __net_init ip6gre_init_net(struct net *net)
1586 {
1587         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1588         struct net_device *ndev;
1589         int err;
1590
1591         if (!net_has_fallback_tunnels(net))
1592                 return 0;
1593         ndev = alloc_netdev(sizeof(struct ip6_tnl), "ip6gre0",
1594                             NET_NAME_UNKNOWN, ip6gre_tunnel_setup);
1595         if (!ndev) {
1596                 err = -ENOMEM;
1597                 goto err_alloc_dev;
1598         }
1599         ign->fb_tunnel_dev = ndev;
1600         dev_net_set(ign->fb_tunnel_dev, net);
1601         /* FB netdevice is special: we have one, and only one per netns.
1602          * Allowing to move it to another netns is clearly unsafe.
1603          */
1604         ign->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL;
1605
1606
1607         ip6gre_fb_tunnel_init(ign->fb_tunnel_dev);
1608         ign->fb_tunnel_dev->rtnl_link_ops = &ip6gre_link_ops;
1609
1610         err = register_netdev(ign->fb_tunnel_dev);
1611         if (err)
1612                 goto err_reg_dev;
1613
1614         rcu_assign_pointer(ign->tunnels_wc[0],
1615                            netdev_priv(ign->fb_tunnel_dev));
1616         return 0;
1617
1618 err_reg_dev:
1619         free_netdev(ndev);
1620 err_alloc_dev:
1621         return err;
1622 }
1623
1624 static void __net_exit ip6gre_exit_batch_net(struct list_head *net_list)
1625 {
1626         struct net *net;
1627         LIST_HEAD(list);
1628
1629         rtnl_lock();
1630         list_for_each_entry(net, net_list, exit_list)
1631                 ip6gre_destroy_tunnels(net, &list);
1632         unregister_netdevice_many(&list);
1633         rtnl_unlock();
1634 }
1635
1636 static struct pernet_operations ip6gre_net_ops = {
1637         .init = ip6gre_init_net,
1638         .exit_batch = ip6gre_exit_batch_net,
1639         .id   = &ip6gre_net_id,
1640         .size = sizeof(struct ip6gre_net),
1641 };
1642
1643 static int ip6gre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[],
1644                                   struct netlink_ext_ack *extack)
1645 {
1646         __be16 flags;
1647
1648         if (!data)
1649                 return 0;
1650
1651         flags = 0;
1652         if (data[IFLA_GRE_IFLAGS])
1653                 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
1654         if (data[IFLA_GRE_OFLAGS])
1655                 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
1656         if (flags & (GRE_VERSION|GRE_ROUTING))
1657                 return -EINVAL;
1658
1659         return 0;
1660 }
1661
1662 static int ip6gre_tap_validate(struct nlattr *tb[], struct nlattr *data[],
1663                                struct netlink_ext_ack *extack)
1664 {
1665         struct in6_addr daddr;
1666
1667         if (tb[IFLA_ADDRESS]) {
1668                 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
1669                         return -EINVAL;
1670                 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
1671                         return -EADDRNOTAVAIL;
1672         }
1673
1674         if (!data)
1675                 goto out;
1676
1677         if (data[IFLA_GRE_REMOTE]) {
1678                 daddr = nla_get_in6_addr(data[IFLA_GRE_REMOTE]);
1679                 if (ipv6_addr_any(&daddr))
1680                         return -EINVAL;
1681         }
1682
1683 out:
1684         return ip6gre_tunnel_validate(tb, data, extack);
1685 }
1686
1687 static int ip6erspan_tap_validate(struct nlattr *tb[], struct nlattr *data[],
1688                                   struct netlink_ext_ack *extack)
1689 {
1690         __be16 flags = 0;
1691         int ret, ver = 0;
1692
1693         if (!data)
1694                 return 0;
1695
1696         ret = ip6gre_tap_validate(tb, data, extack);
1697         if (ret)
1698                 return ret;
1699
1700         /* ERSPAN should only have GRE sequence and key flag */
1701         if (data[IFLA_GRE_OFLAGS])
1702                 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
1703         if (data[IFLA_GRE_IFLAGS])
1704                 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
1705         if (!data[IFLA_GRE_COLLECT_METADATA] &&
1706             flags != (GRE_SEQ | GRE_KEY))
1707                 return -EINVAL;
1708
1709         /* ERSPAN Session ID only has 10-bit. Since we reuse
1710          * 32-bit key field as ID, check it's range.
1711          */
1712         if (data[IFLA_GRE_IKEY] &&
1713             (ntohl(nla_get_be32(data[IFLA_GRE_IKEY])) & ~ID_MASK))
1714                 return -EINVAL;
1715
1716         if (data[IFLA_GRE_OKEY] &&
1717             (ntohl(nla_get_be32(data[IFLA_GRE_OKEY])) & ~ID_MASK))
1718                 return -EINVAL;
1719
1720         if (data[IFLA_GRE_ERSPAN_VER]) {
1721                 ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]);
1722                 if (ver != 1 && ver != 2)
1723                         return -EINVAL;
1724         }
1725
1726         if (ver == 1) {
1727                 if (data[IFLA_GRE_ERSPAN_INDEX]) {
1728                         u32 index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]);
1729
1730                         if (index & ~INDEX_MASK)
1731                                 return -EINVAL;
1732                 }
1733         } else if (ver == 2) {
1734                 if (data[IFLA_GRE_ERSPAN_DIR]) {
1735                         u16 dir = nla_get_u8(data[IFLA_GRE_ERSPAN_DIR]);
1736
1737                         if (dir & ~(DIR_MASK >> DIR_OFFSET))
1738                                 return -EINVAL;
1739                 }
1740
1741                 if (data[IFLA_GRE_ERSPAN_HWID]) {
1742                         u16 hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]);
1743
1744                         if (hwid & ~(HWID_MASK >> HWID_OFFSET))
1745                                 return -EINVAL;
1746                 }
1747         }
1748
1749         return 0;
1750 }
1751
1752 static void ip6erspan_set_version(struct nlattr *data[],
1753                                   struct __ip6_tnl_parm *parms)
1754 {
1755         if (!data)
1756                 return;
1757
1758         parms->erspan_ver = 1;
1759         if (data[IFLA_GRE_ERSPAN_VER])
1760                 parms->erspan_ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]);
1761
1762         if (parms->erspan_ver == 1) {
1763                 if (data[IFLA_GRE_ERSPAN_INDEX])
1764                         parms->index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]);
1765         } else if (parms->erspan_ver == 2) {
1766                 if (data[IFLA_GRE_ERSPAN_DIR])
1767                         parms->dir = nla_get_u8(data[IFLA_GRE_ERSPAN_DIR]);
1768                 if (data[IFLA_GRE_ERSPAN_HWID])
1769                         parms->hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]);
1770         }
1771 }
1772
1773 static void ip6gre_netlink_parms(struct nlattr *data[],
1774                                 struct __ip6_tnl_parm *parms)
1775 {
1776         memset(parms, 0, sizeof(*parms));
1777
1778         if (!data)
1779                 return;
1780
1781         if (data[IFLA_GRE_LINK])
1782                 parms->link = nla_get_u32(data[IFLA_GRE_LINK]);
1783
1784         if (data[IFLA_GRE_IFLAGS])
1785                 parms->i_flags = gre_flags_to_tnl_flags(
1786                                 nla_get_be16(data[IFLA_GRE_IFLAGS]));
1787
1788         if (data[IFLA_GRE_OFLAGS])
1789                 parms->o_flags = gre_flags_to_tnl_flags(
1790                                 nla_get_be16(data[IFLA_GRE_OFLAGS]));
1791
1792         if (data[IFLA_GRE_IKEY])
1793                 parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]);
1794
1795         if (data[IFLA_GRE_OKEY])
1796                 parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]);
1797
1798         if (data[IFLA_GRE_LOCAL])
1799                 parms->laddr = nla_get_in6_addr(data[IFLA_GRE_LOCAL]);
1800
1801         if (data[IFLA_GRE_REMOTE])
1802                 parms->raddr = nla_get_in6_addr(data[IFLA_GRE_REMOTE]);
1803
1804         if (data[IFLA_GRE_TTL])
1805                 parms->hop_limit = nla_get_u8(data[IFLA_GRE_TTL]);
1806
1807         if (data[IFLA_GRE_ENCAP_LIMIT])
1808                 parms->encap_limit = nla_get_u8(data[IFLA_GRE_ENCAP_LIMIT]);
1809
1810         if (data[IFLA_GRE_FLOWINFO])
1811                 parms->flowinfo = nla_get_be32(data[IFLA_GRE_FLOWINFO]);
1812
1813         if (data[IFLA_GRE_FLAGS])
1814                 parms->flags = nla_get_u32(data[IFLA_GRE_FLAGS]);
1815
1816         if (data[IFLA_GRE_FWMARK])
1817                 parms->fwmark = nla_get_u32(data[IFLA_GRE_FWMARK]);
1818
1819         if (data[IFLA_GRE_COLLECT_METADATA])
1820                 parms->collect_md = true;
1821 }
1822
1823 static int ip6gre_tap_init(struct net_device *dev)
1824 {
1825         int ret;
1826
1827         ret = ip6gre_tunnel_init_common(dev);
1828         if (ret)
1829                 return ret;
1830
1831         dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1832
1833         return 0;
1834 }
1835
1836 static const struct net_device_ops ip6gre_tap_netdev_ops = {
1837         .ndo_init = ip6gre_tap_init,
1838         .ndo_uninit = ip6gre_tunnel_uninit,
1839         .ndo_start_xmit = ip6gre_tunnel_xmit,
1840         .ndo_set_mac_address = eth_mac_addr,
1841         .ndo_validate_addr = eth_validate_addr,
1842         .ndo_change_mtu = ip6_tnl_change_mtu,
1843         .ndo_get_stats64 = dev_get_tstats64,
1844         .ndo_get_iflink = ip6_tnl_get_iflink,
1845 };
1846
1847 static int ip6erspan_calc_hlen(struct ip6_tnl *tunnel)
1848 {
1849         int t_hlen;
1850
1851         tunnel->tun_hlen = 8;
1852         tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen +
1853                        erspan_hdr_len(tunnel->parms.erspan_ver);
1854
1855         t_hlen = tunnel->hlen + sizeof(struct ipv6hdr);
1856         tunnel->dev->needed_headroom = LL_MAX_HEADER + t_hlen;
1857         return t_hlen;
1858 }
1859
1860 static int ip6erspan_tap_init(struct net_device *dev)
1861 {
1862         struct ip6_tnl *tunnel;
1863         int t_hlen;
1864         int ret;
1865
1866         tunnel = netdev_priv(dev);
1867
1868         tunnel->dev = dev;
1869         tunnel->net = dev_net(dev);
1870         strcpy(tunnel->parms.name, dev->name);
1871
1872         dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1873         if (!dev->tstats)
1874                 return -ENOMEM;
1875
1876         ret = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
1877         if (ret)
1878                 goto cleanup_alloc_pcpu_stats;
1879
1880         ret = gro_cells_init(&tunnel->gro_cells, dev);
1881         if (ret)
1882                 goto cleanup_dst_cache_init;
1883
1884         t_hlen = ip6erspan_calc_hlen(tunnel);
1885         dev->mtu = ETH_DATA_LEN - t_hlen;
1886         if (dev->type == ARPHRD_ETHER)
1887                 dev->mtu -= ETH_HLEN;
1888         if (!(tunnel->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1889                 dev->mtu -= 8;
1890
1891         dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1892         ip6erspan_tnl_link_config(tunnel, 1);
1893
1894         dev_hold_track(dev, &tunnel->dev_tracker, GFP_KERNEL);
1895         return 0;
1896
1897 cleanup_dst_cache_init:
1898         dst_cache_destroy(&tunnel->dst_cache);
1899 cleanup_alloc_pcpu_stats:
1900         free_percpu(dev->tstats);
1901         dev->tstats = NULL;
1902         return ret;
1903 }
1904
1905 static const struct net_device_ops ip6erspan_netdev_ops = {
1906         .ndo_init =             ip6erspan_tap_init,
1907         .ndo_uninit =           ip6erspan_tunnel_uninit,
1908         .ndo_start_xmit =       ip6erspan_tunnel_xmit,
1909         .ndo_set_mac_address =  eth_mac_addr,
1910         .ndo_validate_addr =    eth_validate_addr,
1911         .ndo_change_mtu =       ip6_tnl_change_mtu,
1912         .ndo_get_stats64 =      dev_get_tstats64,
1913         .ndo_get_iflink =       ip6_tnl_get_iflink,
1914 };
1915
1916 static void ip6gre_tap_setup(struct net_device *dev)
1917 {
1918
1919         ether_setup(dev);
1920
1921         dev->max_mtu = 0;
1922         dev->netdev_ops = &ip6gre_tap_netdev_ops;
1923         dev->needs_free_netdev = true;
1924         dev->priv_destructor = ip6gre_dev_free;
1925
1926         dev->priv_flags &= ~IFF_TX_SKB_SHARING;
1927         dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1928         netif_keep_dst(dev);
1929 }
1930
1931 static bool ip6gre_netlink_encap_parms(struct nlattr *data[],
1932                                        struct ip_tunnel_encap *ipencap)
1933 {
1934         bool ret = false;
1935
1936         memset(ipencap, 0, sizeof(*ipencap));
1937
1938         if (!data)
1939                 return ret;
1940
1941         if (data[IFLA_GRE_ENCAP_TYPE]) {
1942                 ret = true;
1943                 ipencap->type = nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]);
1944         }
1945
1946         if (data[IFLA_GRE_ENCAP_FLAGS]) {
1947                 ret = true;
1948                 ipencap->flags = nla_get_u16(data[IFLA_GRE_ENCAP_FLAGS]);
1949         }
1950
1951         if (data[IFLA_GRE_ENCAP_SPORT]) {
1952                 ret = true;
1953                 ipencap->sport = nla_get_be16(data[IFLA_GRE_ENCAP_SPORT]);
1954         }
1955
1956         if (data[IFLA_GRE_ENCAP_DPORT]) {
1957                 ret = true;
1958                 ipencap->dport = nla_get_be16(data[IFLA_GRE_ENCAP_DPORT]);
1959         }
1960
1961         return ret;
1962 }
1963
1964 static int ip6gre_newlink_common(struct net *src_net, struct net_device *dev,
1965                                  struct nlattr *tb[], struct nlattr *data[],
1966                                  struct netlink_ext_ack *extack)
1967 {
1968         struct ip6_tnl *nt;
1969         struct ip_tunnel_encap ipencap;
1970         int err;
1971
1972         nt = netdev_priv(dev);
1973
1974         if (ip6gre_netlink_encap_parms(data, &ipencap)) {
1975                 int err = ip6_tnl_encap_setup(nt, &ipencap);
1976
1977                 if (err < 0)
1978                         return err;
1979         }
1980
1981         if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS])
1982                 eth_hw_addr_random(dev);
1983
1984         nt->dev = dev;
1985         nt->net = dev_net(dev);
1986
1987         err = register_netdevice(dev);
1988         if (err)
1989                 goto out;
1990
1991         if (tb[IFLA_MTU])
1992                 ip6_tnl_change_mtu(dev, nla_get_u32(tb[IFLA_MTU]));
1993
1994 out:
1995         return err;
1996 }
1997
1998 static int ip6gre_newlink(struct net *src_net, struct net_device *dev,
1999                           struct nlattr *tb[], struct nlattr *data[],
2000                           struct netlink_ext_ack *extack)
2001 {
2002         struct ip6_tnl *nt = netdev_priv(dev);
2003         struct net *net = dev_net(dev);
2004         struct ip6gre_net *ign;
2005         int err;
2006
2007         ip6gre_netlink_parms(data, &nt->parms);
2008         ign = net_generic(net, ip6gre_net_id);
2009
2010         if (nt->parms.collect_md) {
2011                 if (rtnl_dereference(ign->collect_md_tun))
2012                         return -EEXIST;
2013         } else {
2014                 if (ip6gre_tunnel_find(net, &nt->parms, dev->type))
2015                         return -EEXIST;
2016         }
2017
2018         err = ip6gre_newlink_common(src_net, dev, tb, data, extack);
2019         if (!err) {
2020                 ip6gre_tnl_link_config(nt, !tb[IFLA_MTU]);
2021                 ip6gre_tunnel_link_md(ign, nt);
2022                 ip6gre_tunnel_link(net_generic(net, ip6gre_net_id), nt);
2023         }
2024         return err;
2025 }
2026
2027 static struct ip6_tnl *
2028 ip6gre_changelink_common(struct net_device *dev, struct nlattr *tb[],
2029                          struct nlattr *data[], struct __ip6_tnl_parm *p_p,
2030                          struct netlink_ext_ack *extack)
2031 {
2032         struct ip6_tnl *t, *nt = netdev_priv(dev);
2033         struct net *net = nt->net;
2034         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
2035         struct ip_tunnel_encap ipencap;
2036
2037         if (dev == ign->fb_tunnel_dev)
2038                 return ERR_PTR(-EINVAL);
2039
2040         if (ip6gre_netlink_encap_parms(data, &ipencap)) {
2041                 int err = ip6_tnl_encap_setup(nt, &ipencap);
2042
2043                 if (err < 0)
2044                         return ERR_PTR(err);
2045         }
2046
2047         ip6gre_netlink_parms(data, p_p);
2048
2049         t = ip6gre_tunnel_locate(net, p_p, 0);
2050
2051         if (t) {
2052                 if (t->dev != dev)
2053                         return ERR_PTR(-EEXIST);
2054         } else {
2055                 t = nt;
2056         }
2057
2058         return t;
2059 }
2060
2061 static int ip6gre_changelink(struct net_device *dev, struct nlattr *tb[],
2062                              struct nlattr *data[],
2063                              struct netlink_ext_ack *extack)
2064 {
2065         struct ip6_tnl *t = netdev_priv(dev);
2066         struct ip6gre_net *ign = net_generic(t->net, ip6gre_net_id);
2067         struct __ip6_tnl_parm p;
2068
2069         t = ip6gre_changelink_common(dev, tb, data, &p, extack);
2070         if (IS_ERR(t))
2071                 return PTR_ERR(t);
2072
2073         ip6gre_tunnel_unlink_md(ign, t);
2074         ip6gre_tunnel_unlink(ign, t);
2075         ip6gre_tnl_change(t, &p, !tb[IFLA_MTU]);
2076         ip6gre_tunnel_link_md(ign, t);
2077         ip6gre_tunnel_link(ign, t);
2078         return 0;
2079 }
2080
2081 static void ip6gre_dellink(struct net_device *dev, struct list_head *head)
2082 {
2083         struct net *net = dev_net(dev);
2084         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
2085
2086         if (dev != ign->fb_tunnel_dev)
2087                 unregister_netdevice_queue(dev, head);
2088 }
2089
2090 static size_t ip6gre_get_size(const struct net_device *dev)
2091 {
2092         return
2093                 /* IFLA_GRE_LINK */
2094                 nla_total_size(4) +
2095                 /* IFLA_GRE_IFLAGS */
2096                 nla_total_size(2) +
2097                 /* IFLA_GRE_OFLAGS */
2098                 nla_total_size(2) +
2099                 /* IFLA_GRE_IKEY */
2100                 nla_total_size(4) +
2101                 /* IFLA_GRE_OKEY */
2102                 nla_total_size(4) +
2103                 /* IFLA_GRE_LOCAL */
2104                 nla_total_size(sizeof(struct in6_addr)) +
2105                 /* IFLA_GRE_REMOTE */
2106                 nla_total_size(sizeof(struct in6_addr)) +
2107                 /* IFLA_GRE_TTL */
2108                 nla_total_size(1) +
2109                 /* IFLA_GRE_ENCAP_LIMIT */
2110                 nla_total_size(1) +
2111                 /* IFLA_GRE_FLOWINFO */
2112                 nla_total_size(4) +
2113                 /* IFLA_GRE_FLAGS */
2114                 nla_total_size(4) +
2115                 /* IFLA_GRE_ENCAP_TYPE */
2116                 nla_total_size(2) +
2117                 /* IFLA_GRE_ENCAP_FLAGS */
2118                 nla_total_size(2) +
2119                 /* IFLA_GRE_ENCAP_SPORT */
2120                 nla_total_size(2) +
2121                 /* IFLA_GRE_ENCAP_DPORT */
2122                 nla_total_size(2) +
2123                 /* IFLA_GRE_COLLECT_METADATA */
2124                 nla_total_size(0) +
2125                 /* IFLA_GRE_FWMARK */
2126                 nla_total_size(4) +
2127                 /* IFLA_GRE_ERSPAN_INDEX */
2128                 nla_total_size(4) +
2129                 0;
2130 }
2131
2132 static int ip6gre_fill_info(struct sk_buff *skb, const struct net_device *dev)
2133 {
2134         struct ip6_tnl *t = netdev_priv(dev);
2135         struct __ip6_tnl_parm *p = &t->parms;
2136         __be16 o_flags = p->o_flags;
2137
2138         if (p->erspan_ver == 1 || p->erspan_ver == 2) {
2139                 if (!p->collect_md)
2140                         o_flags |= TUNNEL_KEY;
2141
2142                 if (nla_put_u8(skb, IFLA_GRE_ERSPAN_VER, p->erspan_ver))
2143                         goto nla_put_failure;
2144
2145                 if (p->erspan_ver == 1) {
2146                         if (nla_put_u32(skb, IFLA_GRE_ERSPAN_INDEX, p->index))
2147                                 goto nla_put_failure;
2148                 } else {
2149                         if (nla_put_u8(skb, IFLA_GRE_ERSPAN_DIR, p->dir))
2150                                 goto nla_put_failure;
2151                         if (nla_put_u16(skb, IFLA_GRE_ERSPAN_HWID, p->hwid))
2152                                 goto nla_put_failure;
2153                 }
2154         }
2155
2156         if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) ||
2157             nla_put_be16(skb, IFLA_GRE_IFLAGS,
2158                          gre_tnl_flags_to_gre_flags(p->i_flags)) ||
2159             nla_put_be16(skb, IFLA_GRE_OFLAGS,
2160                          gre_tnl_flags_to_gre_flags(o_flags)) ||
2161             nla_put_be32(skb, IFLA_GRE_IKEY, p->i_key) ||
2162             nla_put_be32(skb, IFLA_GRE_OKEY, p->o_key) ||
2163             nla_put_in6_addr(skb, IFLA_GRE_LOCAL, &p->laddr) ||
2164             nla_put_in6_addr(skb, IFLA_GRE_REMOTE, &p->raddr) ||
2165             nla_put_u8(skb, IFLA_GRE_TTL, p->hop_limit) ||
2166             nla_put_u8(skb, IFLA_GRE_ENCAP_LIMIT, p->encap_limit) ||
2167             nla_put_be32(skb, IFLA_GRE_FLOWINFO, p->flowinfo) ||
2168             nla_put_u32(skb, IFLA_GRE_FLAGS, p->flags) ||
2169             nla_put_u32(skb, IFLA_GRE_FWMARK, p->fwmark))
2170                 goto nla_put_failure;
2171
2172         if (nla_put_u16(skb, IFLA_GRE_ENCAP_TYPE,
2173                         t->encap.type) ||
2174             nla_put_be16(skb, IFLA_GRE_ENCAP_SPORT,
2175                          t->encap.sport) ||
2176             nla_put_be16(skb, IFLA_GRE_ENCAP_DPORT,
2177                          t->encap.dport) ||
2178             nla_put_u16(skb, IFLA_GRE_ENCAP_FLAGS,
2179                         t->encap.flags))
2180                 goto nla_put_failure;
2181
2182         if (p->collect_md) {
2183                 if (nla_put_flag(skb, IFLA_GRE_COLLECT_METADATA))
2184                         goto nla_put_failure;
2185         }
2186
2187         return 0;
2188
2189 nla_put_failure:
2190         return -EMSGSIZE;
2191 }
2192
2193 static const struct nla_policy ip6gre_policy[IFLA_GRE_MAX + 1] = {
2194         [IFLA_GRE_LINK]        = { .type = NLA_U32 },
2195         [IFLA_GRE_IFLAGS]      = { .type = NLA_U16 },
2196         [IFLA_GRE_OFLAGS]      = { .type = NLA_U16 },
2197         [IFLA_GRE_IKEY]        = { .type = NLA_U32 },
2198         [IFLA_GRE_OKEY]        = { .type = NLA_U32 },
2199         [IFLA_GRE_LOCAL]       = { .len = sizeof_field(struct ipv6hdr, saddr) },
2200         [IFLA_GRE_REMOTE]      = { .len = sizeof_field(struct ipv6hdr, daddr) },
2201         [IFLA_GRE_TTL]         = { .type = NLA_U8 },
2202         [IFLA_GRE_ENCAP_LIMIT] = { .type = NLA_U8 },
2203         [IFLA_GRE_FLOWINFO]    = { .type = NLA_U32 },
2204         [IFLA_GRE_FLAGS]       = { .type = NLA_U32 },
2205         [IFLA_GRE_ENCAP_TYPE]   = { .type = NLA_U16 },
2206         [IFLA_GRE_ENCAP_FLAGS]  = { .type = NLA_U16 },
2207         [IFLA_GRE_ENCAP_SPORT]  = { .type = NLA_U16 },
2208         [IFLA_GRE_ENCAP_DPORT]  = { .type = NLA_U16 },
2209         [IFLA_GRE_COLLECT_METADATA] = { .type = NLA_FLAG },
2210         [IFLA_GRE_FWMARK]       = { .type = NLA_U32 },
2211         [IFLA_GRE_ERSPAN_INDEX] = { .type = NLA_U32 },
2212         [IFLA_GRE_ERSPAN_VER]   = { .type = NLA_U8 },
2213         [IFLA_GRE_ERSPAN_DIR]   = { .type = NLA_U8 },
2214         [IFLA_GRE_ERSPAN_HWID]  = { .type = NLA_U16 },
2215 };
2216
2217 static void ip6erspan_tap_setup(struct net_device *dev)
2218 {
2219         ether_setup(dev);
2220
2221         dev->max_mtu = 0;
2222         dev->netdev_ops = &ip6erspan_netdev_ops;
2223         dev->needs_free_netdev = true;
2224         dev->priv_destructor = ip6gre_dev_free;
2225
2226         dev->priv_flags &= ~IFF_TX_SKB_SHARING;
2227         dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
2228         netif_keep_dst(dev);
2229 }
2230
2231 static int ip6erspan_newlink(struct net *src_net, struct net_device *dev,
2232                              struct nlattr *tb[], struct nlattr *data[],
2233                              struct netlink_ext_ack *extack)
2234 {
2235         struct ip6_tnl *nt = netdev_priv(dev);
2236         struct net *net = dev_net(dev);
2237         struct ip6gre_net *ign;
2238         int err;
2239
2240         ip6gre_netlink_parms(data, &nt->parms);
2241         ip6erspan_set_version(data, &nt->parms);
2242         ign = net_generic(net, ip6gre_net_id);
2243
2244         if (nt->parms.collect_md) {
2245                 if (rtnl_dereference(ign->collect_md_tun_erspan))
2246                         return -EEXIST;
2247         } else {
2248                 if (ip6gre_tunnel_find(net, &nt->parms, dev->type))
2249                         return -EEXIST;
2250         }
2251
2252         err = ip6gre_newlink_common(src_net, dev, tb, data, extack);
2253         if (!err) {
2254                 ip6erspan_tnl_link_config(nt, !tb[IFLA_MTU]);
2255                 ip6erspan_tunnel_link_md(ign, nt);
2256                 ip6gre_tunnel_link(net_generic(net, ip6gre_net_id), nt);
2257         }
2258         return err;
2259 }
2260
2261 static void ip6erspan_tnl_link_config(struct ip6_tnl *t, int set_mtu)
2262 {
2263         ip6gre_tnl_link_config_common(t);
2264         ip6gre_tnl_link_config_route(t, set_mtu, ip6erspan_calc_hlen(t));
2265 }
2266
2267 static int ip6erspan_tnl_change(struct ip6_tnl *t,
2268                                 const struct __ip6_tnl_parm *p, int set_mtu)
2269 {
2270         ip6gre_tnl_copy_tnl_parm(t, p);
2271         ip6erspan_tnl_link_config(t, set_mtu);
2272         return 0;
2273 }
2274
2275 static int ip6erspan_changelink(struct net_device *dev, struct nlattr *tb[],
2276                                 struct nlattr *data[],
2277                                 struct netlink_ext_ack *extack)
2278 {
2279         struct ip6gre_net *ign = net_generic(dev_net(dev), ip6gre_net_id);
2280         struct __ip6_tnl_parm p;
2281         struct ip6_tnl *t;
2282
2283         t = ip6gre_changelink_common(dev, tb, data, &p, extack);
2284         if (IS_ERR(t))
2285                 return PTR_ERR(t);
2286
2287         ip6erspan_set_version(data, &p);
2288         ip6gre_tunnel_unlink_md(ign, t);
2289         ip6gre_tunnel_unlink(ign, t);
2290         ip6erspan_tnl_change(t, &p, !tb[IFLA_MTU]);
2291         ip6erspan_tunnel_link_md(ign, t);
2292         ip6gre_tunnel_link(ign, t);
2293         return 0;
2294 }
2295
2296 static struct rtnl_link_ops ip6gre_link_ops __read_mostly = {
2297         .kind           = "ip6gre",
2298         .maxtype        = IFLA_GRE_MAX,
2299         .policy         = ip6gre_policy,
2300         .priv_size      = sizeof(struct ip6_tnl),
2301         .setup          = ip6gre_tunnel_setup,
2302         .validate       = ip6gre_tunnel_validate,
2303         .newlink        = ip6gre_newlink,
2304         .changelink     = ip6gre_changelink,
2305         .dellink        = ip6gre_dellink,
2306         .get_size       = ip6gre_get_size,
2307         .fill_info      = ip6gre_fill_info,
2308         .get_link_net   = ip6_tnl_get_link_net,
2309 };
2310
2311 static struct rtnl_link_ops ip6gre_tap_ops __read_mostly = {
2312         .kind           = "ip6gretap",
2313         .maxtype        = IFLA_GRE_MAX,
2314         .policy         = ip6gre_policy,
2315         .priv_size      = sizeof(struct ip6_tnl),
2316         .setup          = ip6gre_tap_setup,
2317         .validate       = ip6gre_tap_validate,
2318         .newlink        = ip6gre_newlink,
2319         .changelink     = ip6gre_changelink,
2320         .get_size       = ip6gre_get_size,
2321         .fill_info      = ip6gre_fill_info,
2322         .get_link_net   = ip6_tnl_get_link_net,
2323 };
2324
2325 static struct rtnl_link_ops ip6erspan_tap_ops __read_mostly = {
2326         .kind           = "ip6erspan",
2327         .maxtype        = IFLA_GRE_MAX,
2328         .policy         = ip6gre_policy,
2329         .priv_size      = sizeof(struct ip6_tnl),
2330         .setup          = ip6erspan_tap_setup,
2331         .validate       = ip6erspan_tap_validate,
2332         .newlink        = ip6erspan_newlink,
2333         .changelink     = ip6erspan_changelink,
2334         .get_size       = ip6gre_get_size,
2335         .fill_info      = ip6gre_fill_info,
2336         .get_link_net   = ip6_tnl_get_link_net,
2337 };
2338
2339 /*
2340  *      And now the modules code and kernel interface.
2341  */
2342
2343 static int __init ip6gre_init(void)
2344 {
2345         int err;
2346
2347         pr_info("GRE over IPv6 tunneling driver\n");
2348
2349         err = register_pernet_device(&ip6gre_net_ops);
2350         if (err < 0)
2351                 return err;
2352
2353         err = inet6_add_protocol(&ip6gre_protocol, IPPROTO_GRE);
2354         if (err < 0) {
2355                 pr_info("%s: can't add protocol\n", __func__);
2356                 goto add_proto_failed;
2357         }
2358
2359         err = rtnl_link_register(&ip6gre_link_ops);
2360         if (err < 0)
2361                 goto rtnl_link_failed;
2362
2363         err = rtnl_link_register(&ip6gre_tap_ops);
2364         if (err < 0)
2365                 goto tap_ops_failed;
2366
2367         err = rtnl_link_register(&ip6erspan_tap_ops);
2368         if (err < 0)
2369                 goto erspan_link_failed;
2370
2371 out:
2372         return err;
2373
2374 erspan_link_failed:
2375         rtnl_link_unregister(&ip6gre_tap_ops);
2376 tap_ops_failed:
2377         rtnl_link_unregister(&ip6gre_link_ops);
2378 rtnl_link_failed:
2379         inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE);
2380 add_proto_failed:
2381         unregister_pernet_device(&ip6gre_net_ops);
2382         goto out;
2383 }
2384
2385 static void __exit ip6gre_fini(void)
2386 {
2387         rtnl_link_unregister(&ip6gre_tap_ops);
2388         rtnl_link_unregister(&ip6gre_link_ops);
2389         rtnl_link_unregister(&ip6erspan_tap_ops);
2390         inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE);
2391         unregister_pernet_device(&ip6gre_net_ops);
2392 }
2393
2394 module_init(ip6gre_init);
2395 module_exit(ip6gre_fini);
2396 MODULE_LICENSE("GPL");
2397 MODULE_AUTHOR("D. Kozlov ([email protected])");
2398 MODULE_DESCRIPTION("GRE over IPv6 tunneling device");
2399 MODULE_ALIAS_RTNL_LINK("ip6gre");
2400 MODULE_ALIAS_RTNL_LINK("ip6gretap");
2401 MODULE_ALIAS_RTNL_LINK("ip6erspan");
2402 MODULE_ALIAS_NETDEV("ip6gre0");