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         if (csum && skb_checksum_start(skb) < skb->data)
 633                 return -EINVAL;
 634         return iptunnel_handle_offloads(skb,
 635                                         csum ? SKB_GSO_GRE_CSUM : SKB_GSO_GRE);
 636 }
 637
 638 static void prepare_ip6gre_xmit_ipv4(struct sk_buff *skb,
 639                                      struct net_device *dev,
 640                                      struct flowi6 *fl6, __u8 *dsfield,
 641                                      int *encap_limit)
 642 {
 643         const struct iphdr *iph = ip_hdr(skb);
 644         struct ip6_tnl *t = netdev_priv(dev);
 645
 646         if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
 647                 *encap_limit = t->parms.encap_limit;
 648
 649         memcpy(fl6, &t->fl.u.ip6, sizeof(*fl6));
 650
 651         if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
 652                 *dsfield = ipv4_get_dsfield(iph);
 653         else
 654                 *dsfield = ip6_tclass(t->parms.flowinfo);
 655
 656         if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
 657                 fl6->flowi6_mark = skb->mark;
 658         else
 659                 fl6->flowi6_mark = t->parms.fwmark;
 660
 661         fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
 662 }
 663
 664 static int prepare_ip6gre_xmit_ipv6(struct sk_buff *skb,
 665                                     struct net_device *dev,
 666                                     struct flowi6 *fl6, __u8 *dsfield,
 667                                     int *encap_limit)
 668 {
 669         struct ipv6hdr *ipv6h;
 670         struct ip6_tnl *t = netdev_priv(dev);
 671         __u16 offset;
 672
 673         offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb));
 674         /* ip6_tnl_parse_tlv_enc_lim() might have reallocated skb->head */
 675         ipv6h = ipv6_hdr(skb);
 676
 677         if (offset > 0) {
 678                 struct ipv6_tlv_tnl_enc_lim *tel;
 679
 680                 tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset];
 681                 if (tel->encap_limit == 0) {
 682                         icmpv6_ndo_send(skb, ICMPV6_PARAMPROB,
 683                                         ICMPV6_HDR_FIELD, offset + 2);
 684                         return -1;
 685                 }
 686                 *encap_limit = tel->encap_limit - 1;
 687         } else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) {
 688                 *encap_limit = t->parms.encap_limit;
 689         }
 690
 691         memcpy(fl6, &t->fl.u.ip6, sizeof(*fl6));
 692
 693         if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
 694                 *dsfield = ipv6_get_dsfield(ipv6h);
 695         else
 696                 *dsfield = ip6_tclass(t->parms.flowinfo);
 697
 698         if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL)
 699                 fl6->flowlabel |= ip6_flowlabel(ipv6h);
 700
 701         if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
 702                 fl6->flowi6_mark = skb->mark;
 703         else
 704                 fl6->flowi6_mark = t->parms.fwmark;
 705
 706         fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
 707
 708         return 0;
 709 }
 710
 711 static struct ip_tunnel_info *skb_tunnel_info_txcheck(struct sk_buff *skb)
 712 {
 713         struct ip_tunnel_info *tun_info;
 714
 715         tun_info = skb_tunnel_info(skb);
 716         if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX)))
 717                 return ERR_PTR(-EINVAL);
 718
 719         return tun_info;
 720 }
 721
 722 static netdev_tx_t __gre6_xmit(struct sk_buff *skb,
 723                                struct net_device *dev, __u8 dsfield,
 724                                struct flowi6 *fl6, int encap_limit,
 725                                __u32 *pmtu, __be16 proto)
 726 {
 727         struct ip6_tnl *tunnel = netdev_priv(dev);
 728         __be16 protocol;
 729
 730         if (dev->type == ARPHRD_ETHER)
 731                 IPCB(skb)->flags = 0;
 732
 733         if (dev->header_ops && dev->type == ARPHRD_IP6GRE)
 734                 fl6->daddr = ((struct ipv6hdr *)skb->data)->daddr;
 735         else
 736                 fl6->daddr = tunnel->parms.raddr;
 737
 738         if (skb_cow_head(skb, dev->needed_headroom ?: tunnel->hlen))
 739                 return -ENOMEM;
 740
 741         /* Push GRE header. */
 742         protocol = (dev->type == ARPHRD_ETHER) ? htons(ETH_P_TEB) : proto;
 743
 744         if (tunnel->parms.collect_md) {
 745                 struct ip_tunnel_info *tun_info;
 746                 const struct ip_tunnel_key *key;
 747                 __be16 flags;
 748
 749                 tun_info = skb_tunnel_info_txcheck(skb);
 750                 if (IS_ERR(tun_info) ||
 751                     unlikely(ip_tunnel_info_af(tun_info) != AF_INET6))
 752                         return -EINVAL;
 753
 754                 key = &tun_info->key;
 755                 memset(fl6, 0, sizeof(*fl6));
 756                 fl6->flowi6_proto = IPPROTO_GRE;
 757                 fl6->daddr = key->u.ipv6.dst;
 758                 fl6->flowlabel = key->label;
 759                 fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
 760
 761                 dsfield = key->tos;
 762                 flags = key->tun_flags &
 763                         (TUNNEL_CSUM | TUNNEL_KEY | TUNNEL_SEQ);
 764                 tunnel->tun_hlen = gre_calc_hlen(flags);
 765
 766                 gre_build_header(skb, tunnel->tun_hlen,
 767                                  flags, protocol,
 768                                  tunnel_id_to_key32(tun_info->key.tun_id),
 769                                  (flags & TUNNEL_SEQ) ? htonl(tunnel->o_seqno++)
 770                                                       : 0);
 771
 772         } else {
 773                 if (tunnel->parms.o_flags & TUNNEL_SEQ)
 774                         tunnel->o_seqno++;
 775
 776                 gre_build_header(skb, tunnel->tun_hlen, tunnel->parms.o_flags,
 777                                  protocol, tunnel->parms.o_key,
 778                                  htonl(tunnel->o_seqno));
 779         }
 780
 781         return ip6_tnl_xmit(skb, dev, dsfield, fl6, encap_limit, pmtu,
 782                             NEXTHDR_GRE);
 783 }
 784
 785 static inline int ip6gre_xmit_ipv4(struct sk_buff *skb, struct net_device *dev)
 786 {
 787         struct ip6_tnl *t = netdev_priv(dev);
 788         int encap_limit = -1;
 789         struct flowi6 fl6;
 790         __u8 dsfield = 0;
 791         __u32 mtu;
 792         int err;
 793
 794         memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
 795
 796         if (!t->parms.collect_md)
 797                 prepare_ip6gre_xmit_ipv4(skb, dev, &fl6,
 798                                          &dsfield, &encap_limit);
 799
 800         err = gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM));
 801         if (err)
 802                 return -1;
 803
 804         err = __gre6_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu,
 805                           skb->protocol);
 806         if (err != 0) {
 807                 /* XXX: send ICMP error even if DF is not set. */
 808                 if (err == -EMSGSIZE)
 809                         icmp_ndo_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
 810                                       htonl(mtu));
 811                 return -1;
 812         }
 813
 814         return 0;
 815 }
 816
 817 static inline int ip6gre_xmit_ipv6(struct sk_buff *skb, struct net_device *dev)
 818 {
 819         struct ip6_tnl *t = netdev_priv(dev);
 820         struct ipv6hdr *ipv6h = ipv6_hdr(skb);
 821         int encap_limit = -1;
 822         struct flowi6 fl6;
 823         __u8 dsfield = 0;
 824         __u32 mtu;
 825         int err;
 826
 827         if (ipv6_addr_equal(&t->parms.raddr, &ipv6h->saddr))
 828                 return -1;
 829
 830         if (!t->parms.collect_md &&
 831             prepare_ip6gre_xmit_ipv6(skb, dev, &fl6, &dsfield, &encap_limit))
 832                 return -1;
 833
 834         if (gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM)))
 835                 return -1;
 836
 837         err = __gre6_xmit(skb, dev, dsfield, &fl6, encap_limit,
 838                           &mtu, skb->protocol);
 839         if (err != 0) {
 840                 if (err == -EMSGSIZE)
 841                         icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
 842                 return -1;
 843         }
 844
 845         return 0;
 846 }
 847
 848 /**
 849  * ip6gre_tnl_addr_conflict - compare packet addresses to tunnel's own
 850  *   @t: the outgoing tunnel device
 851  *   @hdr: IPv6 header from the incoming packet
 852  *
 853  * Description:
 854  *   Avoid trivial tunneling loop by checking that tunnel exit-point
 855  *   doesn't match source of incoming packet.
 856  *
 857  * Return:
 858  *   1 if conflict,
 859  *   0 else
 860  **/
 861
 862 static inline bool ip6gre_tnl_addr_conflict(const struct ip6_tnl *t,
 863         const struct ipv6hdr *hdr)
 864 {
 865         return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr);
 866 }
 867
 868 static int ip6gre_xmit_other(struct sk_buff *skb, struct net_device *dev)
 869 {
 870         struct ip6_tnl *t = netdev_priv(dev);
 871         int encap_limit = -1;
 872         struct flowi6 fl6;
 873         __u32 mtu;
 874         int err;
 875
 876         if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
 877                 encap_limit = t->parms.encap_limit;
 878
 879         if (!t->parms.collect_md)
 880                 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
 881
 882         err = gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM));
 883         if (err)
 884                 return err;
 885
 886         err = __gre6_xmit(skb, dev, 0, &fl6, encap_limit, &mtu, skb->protocol);
 887
 888         return err;
 889 }
 890
 891 static netdev_tx_t ip6gre_tunnel_xmit(struct sk_buff *skb,
 892         struct net_device *dev)
 893 {
 894         struct ip6_tnl *t = netdev_priv(dev);
 895         struct net_device_stats *stats = &t->dev->stats;
 896         int ret;
 897
 898         if (!pskb_inet_may_pull(skb))
 899                 goto tx_err;
 900
 901         if (!ip6_tnl_xmit_ctl(t, &t->parms.laddr, &t->parms.raddr))
 902                 goto tx_err;
 903
 904         switch (skb->protocol) {
 905         case htons(ETH_P_IP):
 906                 ret = ip6gre_xmit_ipv4(skb, dev);
 907                 break;
 908         case htons(ETH_P_IPV6):
 909                 ret = ip6gre_xmit_ipv6(skb, dev);
 910                 break;
 911         default:
 912                 ret = ip6gre_xmit_other(skb, dev);
 913                 break;
 914         }
 915
 916         if (ret < 0)
 917                 goto tx_err;
 918
 919         return NETDEV_TX_OK;
 920
 921 tx_err:
 922         if (!t->parms.collect_md || !IS_ERR(skb_tunnel_info_txcheck(skb)))
 923                 stats->tx_errors++;
 924         stats->tx_dropped++;
 925         kfree_skb(skb);
 926         return NETDEV_TX_OK;
 927 }
 928
 929 static netdev_tx_t ip6erspan_tunnel_xmit(struct sk_buff *skb,
 930                                          struct net_device *dev)
 931 {
 932         struct ip_tunnel_info *tun_info = NULL;
 933         struct ip6_tnl *t = netdev_priv(dev);
 934         struct dst_entry *dst = skb_dst(skb);
 935         struct net_device_stats *stats;
 936         bool truncate = false;
 937         int encap_limit = -1;
 938         __u8 dsfield = false;
 939         struct flowi6 fl6;
 940         int err = -EINVAL;
 941         __be16 proto;
 942         __u32 mtu;
 943         int nhoff;
 944         int thoff;
 945
 946         if (!pskb_inet_may_pull(skb))
 947                 goto tx_err;
 948
 949         if (!ip6_tnl_xmit_ctl(t, &t->parms.laddr, &t->parms.raddr))
 950                 goto tx_err;
 951
 952         if (gre_handle_offloads(skb, false))
 953                 goto tx_err;
 954
 955         if (skb->len > dev->mtu + dev->hard_header_len) {
 956                 pskb_trim(skb, dev->mtu + dev->hard_header_len);
 957                 truncate = true;
 958         }
 959
 960         nhoff = skb_network_header(skb) - skb_mac_header(skb);
 961         if (skb->protocol == htons(ETH_P_IP) &&
 962             (ntohs(ip_hdr(skb)->tot_len) > skb->len - nhoff))
 963                 truncate = true;
 964
 965         thoff = skb_transport_header(skb) - skb_mac_header(skb);
 966         if (skb->protocol == htons(ETH_P_IPV6) &&
 967             (ntohs(ipv6_hdr(skb)->payload_len) > skb->len - thoff))
 968                 truncate = true;
 969
 970         if (skb_cow_head(skb, dev->needed_headroom ?: t->hlen))
 971                 goto tx_err;
 972
 973         t->parms.o_flags &= ~TUNNEL_KEY;
 974         IPCB(skb)->flags = 0;
 975
 976         /* For collect_md mode, derive fl6 from the tunnel key,
 977          * for native mode, call prepare_ip6gre_xmit_{ipv4,ipv6}.
 978          */
 979         if (t->parms.collect_md) {
 980                 const struct ip_tunnel_key *key;
 981                 struct erspan_metadata *md;
 982                 __be32 tun_id;
 983
 984                 tun_info = skb_tunnel_info_txcheck(skb);
 985                 if (IS_ERR(tun_info) ||
 986                     unlikely(ip_tunnel_info_af(tun_info) != AF_INET6))
 987                         goto tx_err;
 988
 989                 key = &tun_info->key;
 990                 memset(&fl6, 0, sizeof(fl6));
 991                 fl6.flowi6_proto = IPPROTO_GRE;
 992                 fl6.daddr = key->u.ipv6.dst;
 993                 fl6.flowlabel = key->label;
 994                 fl6.flowi6_uid = sock_net_uid(dev_net(dev), NULL);
 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                 memcpy(dev->dev_addr, &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
1104         if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS))
1105                 fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo;
1106         if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL))
1107                 fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo;
1108
1109         p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET);
1110         p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr);
1111
1112         if (p->flags&IP6_TNL_F_CAP_XMIT &&
1113                         p->flags&IP6_TNL_F_CAP_RCV && dev->type != ARPHRD_ETHER)
1114                 dev->flags |= IFF_POINTOPOINT;
1115         else
1116                 dev->flags &= ~IFF_POINTOPOINT;
1117 }
1118
1119 static void ip6gre_tnl_link_config_route(struct ip6_tnl *t, int set_mtu,
1120                                          int t_hlen)
1121 {
1122         const struct __ip6_tnl_parm *p = &t->parms;
1123         struct net_device *dev = t->dev;
1124
1125         if (p->flags & IP6_TNL_F_CAP_XMIT) {
1126                 int strict = (ipv6_addr_type(&p->raddr) &
1127                               (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL));
1128
1129                 struct rt6_info *rt = rt6_lookup(t->net,
1130                                                  &p->raddr, &p->laddr,
1131                                                  p->link, NULL, strict);
1132
1133                 if (!rt)
1134                         return;
1135
1136                 if (rt->dst.dev) {
1137                         unsigned short dst_len = rt->dst.dev->hard_header_len +
1138                                                  t_hlen;
1139
1140                         if (t->dev->header_ops)
1141                                 dev->hard_header_len = dst_len;
1142                         else
1143                                 dev->needed_headroom = dst_len;
1144
1145                         if (set_mtu) {
1146                                 dev->mtu = rt->dst.dev->mtu - t_hlen;
1147                                 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1148                                         dev->mtu -= 8;
1149                                 if (dev->type == ARPHRD_ETHER)
1150                                         dev->mtu -= ETH_HLEN;
1151
1152                                 if (dev->mtu < IPV6_MIN_MTU)
1153                                         dev->mtu = IPV6_MIN_MTU;
1154                         }
1155                 }
1156                 ip6_rt_put(rt);
1157         }
1158 }
1159
1160 static int ip6gre_calc_hlen(struct ip6_tnl *tunnel)
1161 {
1162         int t_hlen;
1163
1164         tunnel->tun_hlen = gre_calc_hlen(tunnel->parms.o_flags);
1165         tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen;
1166
1167         t_hlen = tunnel->hlen + sizeof(struct ipv6hdr);
1168
1169         if (tunnel->dev->header_ops)
1170                 tunnel->dev->hard_header_len = LL_MAX_HEADER + t_hlen;
1171         else
1172                 tunnel->dev->needed_headroom = LL_MAX_HEADER + t_hlen;
1173
1174         return t_hlen;
1175 }
1176
1177 static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu)
1178 {
1179         ip6gre_tnl_link_config_common(t);
1180         ip6gre_tnl_link_config_route(t, set_mtu, ip6gre_calc_hlen(t));
1181 }
1182
1183 static void ip6gre_tnl_copy_tnl_parm(struct ip6_tnl *t,
1184                                      const struct __ip6_tnl_parm *p)
1185 {
1186         t->parms.laddr = p->laddr;
1187         t->parms.raddr = p->raddr;
1188         t->parms.flags = p->flags;
1189         t->parms.hop_limit = p->hop_limit;
1190         t->parms.encap_limit = p->encap_limit;
1191         t->parms.flowinfo = p->flowinfo;
1192         t->parms.link = p->link;
1193         t->parms.proto = p->proto;
1194         t->parms.i_key = p->i_key;
1195         t->parms.o_key = p->o_key;
1196         t->parms.i_flags = p->i_flags;
1197         t->parms.o_flags = p->o_flags;
1198         t->parms.fwmark = p->fwmark;
1199         t->parms.erspan_ver = p->erspan_ver;
1200         t->parms.index = p->index;
1201         t->parms.dir = p->dir;
1202         t->parms.hwid = p->hwid;
1203         dst_cache_reset(&t->dst_cache);
1204 }
1205
1206 static int ip6gre_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p,
1207                              int set_mtu)
1208 {
1209         ip6gre_tnl_copy_tnl_parm(t, p);
1210         ip6gre_tnl_link_config(t, set_mtu);
1211         return 0;
1212 }
1213
1214 static void ip6gre_tnl_parm_from_user(struct __ip6_tnl_parm *p,
1215         const struct ip6_tnl_parm2 *u)
1216 {
1217         p->laddr = u->laddr;
1218         p->raddr = u->raddr;
1219         p->flags = u->flags;
1220         p->hop_limit = u->hop_limit;
1221         p->encap_limit = u->encap_limit;
1222         p->flowinfo = u->flowinfo;
1223         p->link = u->link;
1224         p->i_key = u->i_key;
1225         p->o_key = u->o_key;
1226         p->i_flags = gre_flags_to_tnl_flags(u->i_flags);
1227         p->o_flags = gre_flags_to_tnl_flags(u->o_flags);
1228         memcpy(p->name, u->name, sizeof(u->name));
1229 }
1230
1231 static void ip6gre_tnl_parm_to_user(struct ip6_tnl_parm2 *u,
1232         const struct __ip6_tnl_parm *p)
1233 {
1234         u->proto = IPPROTO_GRE;
1235         u->laddr = p->laddr;
1236         u->raddr = p->raddr;
1237         u->flags = p->flags;
1238         u->hop_limit = p->hop_limit;
1239         u->encap_limit = p->encap_limit;
1240         u->flowinfo = p->flowinfo;
1241         u->link = p->link;
1242         u->i_key = p->i_key;
1243         u->o_key = p->o_key;
1244         u->i_flags = gre_tnl_flags_to_gre_flags(p->i_flags);
1245         u->o_flags = gre_tnl_flags_to_gre_flags(p->o_flags);
1246         memcpy(u->name, p->name, sizeof(u->name));
1247 }
1248
1249 static int ip6gre_tunnel_siocdevprivate(struct net_device *dev,
1250                                         struct ifreq *ifr, void __user *data,
1251                                         int cmd)
1252 {
1253         int err = 0;
1254         struct ip6_tnl_parm2 p;
1255         struct __ip6_tnl_parm p1;
1256         struct ip6_tnl *t = netdev_priv(dev);
1257         struct net *net = t->net;
1258         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1259
1260         memset(&p1, 0, sizeof(p1));
1261
1262         switch (cmd) {
1263         case SIOCGETTUNNEL:
1264                 if (dev == ign->fb_tunnel_dev) {
1265                         if (copy_from_user(&p, data, sizeof(p))) {
1266                                 err = -EFAULT;
1267                                 break;
1268                         }
1269                         ip6gre_tnl_parm_from_user(&p1, &p);
1270                         t = ip6gre_tunnel_locate(net, &p1, 0);
1271                         if (!t)
1272                                 t = netdev_priv(dev);
1273                 }
1274                 memset(&p, 0, sizeof(p));
1275                 ip6gre_tnl_parm_to_user(&p, &t->parms);
1276                 if (copy_to_user(data, &p, sizeof(p)))
1277                         err = -EFAULT;
1278                 break;
1279
1280         case SIOCADDTUNNEL:
1281         case SIOCCHGTUNNEL:
1282                 err = -EPERM;
1283                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1284                         goto done;
1285
1286                 err = -EFAULT;
1287                 if (copy_from_user(&p, data, sizeof(p)))
1288                         goto done;
1289
1290                 err = -EINVAL;
1291                 if ((p.i_flags|p.o_flags)&(GRE_VERSION|GRE_ROUTING))
1292                         goto done;
1293
1294                 if (!(p.i_flags&GRE_KEY))
1295                         p.i_key = 0;
1296                 if (!(p.o_flags&GRE_KEY))
1297                         p.o_key = 0;
1298
1299                 ip6gre_tnl_parm_from_user(&p1, &p);
1300                 t = ip6gre_tunnel_locate(net, &p1, cmd == SIOCADDTUNNEL);
1301
1302                 if (dev != ign->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
1303                         if (t) {
1304                                 if (t->dev != dev) {
1305                                         err = -EEXIST;
1306                                         break;
1307                                 }
1308                         } else {
1309                                 t = netdev_priv(dev);
1310
1311                                 ip6gre_tunnel_unlink(ign, t);
1312                                 synchronize_net();
1313                                 ip6gre_tnl_change(t, &p1, 1);
1314                                 ip6gre_tunnel_link(ign, t);
1315                                 netdev_state_change(dev);
1316                         }
1317                 }
1318
1319                 if (t) {
1320                         err = 0;
1321
1322                         memset(&p, 0, sizeof(p));
1323                         ip6gre_tnl_parm_to_user(&p, &t->parms);
1324                         if (copy_to_user(data, &p, sizeof(p)))
1325                                 err = -EFAULT;
1326                 } else
1327                         err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
1328                 break;
1329
1330         case SIOCDELTUNNEL:
1331                 err = -EPERM;
1332                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1333                         goto done;
1334
1335                 if (dev == ign->fb_tunnel_dev) {
1336                         err = -EFAULT;
1337                         if (copy_from_user(&p, data, sizeof(p)))
1338                                 goto done;
1339                         err = -ENOENT;
1340                         ip6gre_tnl_parm_from_user(&p1, &p);
1341                         t = ip6gre_tunnel_locate(net, &p1, 0);
1342                         if (!t)
1343                                 goto done;
1344                         err = -EPERM;
1345                         if (t == netdev_priv(ign->fb_tunnel_dev))
1346                                 goto done;
1347                         dev = t->dev;
1348                 }
1349                 unregister_netdevice(dev);
1350                 err = 0;
1351                 break;
1352
1353         default:
1354                 err = -EINVAL;
1355         }
1356
1357 done:
1358         return err;
1359 }
1360
1361 static int ip6gre_header(struct sk_buff *skb, struct net_device *dev,
1362                          unsigned short type, const void *daddr,
1363                          const void *saddr, unsigned int len)
1364 {
1365         struct ip6_tnl *t = netdev_priv(dev);
1366         struct ipv6hdr *ipv6h;
1367         __be16 *p;
1368
1369         ipv6h = skb_push(skb, t->hlen + sizeof(*ipv6h));
1370         ip6_flow_hdr(ipv6h, 0, ip6_make_flowlabel(dev_net(dev), skb,
1371                                                   t->fl.u.ip6.flowlabel,
1372                                                   true, &t->fl.u.ip6));
1373         ipv6h->hop_limit = t->parms.hop_limit;
1374         ipv6h->nexthdr = NEXTHDR_GRE;
1375         ipv6h->saddr = t->parms.laddr;
1376         ipv6h->daddr = t->parms.raddr;
1377
1378         p = (__be16 *)(ipv6h + 1);
1379         p[0] = t->parms.o_flags;
1380         p[1] = htons(type);
1381
1382         /*
1383          *      Set the source hardware address.
1384          */
1385
1386         if (saddr)
1387                 memcpy(&ipv6h->saddr, saddr, sizeof(struct in6_addr));
1388         if (daddr)
1389                 memcpy(&ipv6h->daddr, daddr, sizeof(struct in6_addr));
1390         if (!ipv6_addr_any(&ipv6h->daddr))
1391                 return t->hlen;
1392
1393         return -t->hlen;
1394 }
1395
1396 static const struct header_ops ip6gre_header_ops = {
1397         .create = ip6gre_header,
1398 };
1399
1400 static const struct net_device_ops ip6gre_netdev_ops = {
1401         .ndo_init               = ip6gre_tunnel_init,
1402         .ndo_uninit             = ip6gre_tunnel_uninit,
1403         .ndo_start_xmit         = ip6gre_tunnel_xmit,
1404         .ndo_siocdevprivate     = ip6gre_tunnel_siocdevprivate,
1405         .ndo_change_mtu         = ip6_tnl_change_mtu,
1406         .ndo_get_stats64        = dev_get_tstats64,
1407         .ndo_get_iflink         = ip6_tnl_get_iflink,
1408 };
1409
1410 static void ip6gre_dev_free(struct net_device *dev)
1411 {
1412         struct ip6_tnl *t = netdev_priv(dev);
1413
1414         gro_cells_destroy(&t->gro_cells);
1415         dst_cache_destroy(&t->dst_cache);
1416         free_percpu(dev->tstats);
1417 }
1418
1419 static void ip6gre_tunnel_setup(struct net_device *dev)
1420 {
1421         dev->netdev_ops = &ip6gre_netdev_ops;
1422         dev->needs_free_netdev = true;
1423         dev->priv_destructor = ip6gre_dev_free;
1424
1425         dev->type = ARPHRD_IP6GRE;
1426
1427         dev->flags |= IFF_NOARP;
1428         dev->addr_len = sizeof(struct in6_addr);
1429         netif_keep_dst(dev);
1430         /* This perm addr will be used as interface identifier by IPv6 */
1431         dev->addr_assign_type = NET_ADDR_RANDOM;
1432         eth_random_addr(dev->perm_addr);
1433 }
1434
1435 #define GRE6_FEATURES (NETIF_F_SG |             \
1436                        NETIF_F_FRAGLIST |       \
1437                        NETIF_F_HIGHDMA |        \
1438                        NETIF_F_HW_CSUM)
1439
1440 static void ip6gre_tnl_init_features(struct net_device *dev)
1441 {
1442         struct ip6_tnl *nt = netdev_priv(dev);
1443
1444         dev->features           |= GRE6_FEATURES;
1445         dev->hw_features        |= GRE6_FEATURES;
1446
1447         if (!(nt->parms.o_flags & TUNNEL_SEQ)) {
1448                 /* TCP offload with GRE SEQ is not supported, nor
1449                  * can we support 2 levels of outer headers requiring
1450                  * an update.
1451                  */
1452                 if (!(nt->parms.o_flags & TUNNEL_CSUM) ||
1453                     nt->encap.type == TUNNEL_ENCAP_NONE) {
1454                         dev->features    |= NETIF_F_GSO_SOFTWARE;
1455                         dev->hw_features |= NETIF_F_GSO_SOFTWARE;
1456                 }
1457
1458                 /* Can use a lockless transmit, unless we generate
1459                  * output sequences
1460                  */
1461                 dev->features |= NETIF_F_LLTX;
1462         }
1463 }
1464
1465 static int ip6gre_tunnel_init_common(struct net_device *dev)
1466 {
1467         struct ip6_tnl *tunnel;
1468         int ret;
1469         int t_hlen;
1470
1471         tunnel = netdev_priv(dev);
1472
1473         tunnel->dev = dev;
1474         tunnel->net = dev_net(dev);
1475         strcpy(tunnel->parms.name, dev->name);
1476
1477         dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1478         if (!dev->tstats)
1479                 return -ENOMEM;
1480
1481         ret = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
1482         if (ret)
1483                 goto cleanup_alloc_pcpu_stats;
1484
1485         ret = gro_cells_init(&tunnel->gro_cells, dev);
1486         if (ret)
1487                 goto cleanup_dst_cache_init;
1488
1489         t_hlen = ip6gre_calc_hlen(tunnel);
1490         dev->mtu = ETH_DATA_LEN - t_hlen;
1491         if (dev->type == ARPHRD_ETHER)
1492                 dev->mtu -= ETH_HLEN;
1493         if (!(tunnel->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1494                 dev->mtu -= 8;
1495
1496         if (tunnel->parms.collect_md) {
1497                 netif_keep_dst(dev);
1498         }
1499         ip6gre_tnl_init_features(dev);
1500
1501         dev_hold(dev);
1502         return 0;
1503
1504 cleanup_dst_cache_init:
1505         dst_cache_destroy(&tunnel->dst_cache);
1506 cleanup_alloc_pcpu_stats:
1507         free_percpu(dev->tstats);
1508         dev->tstats = NULL;
1509         return ret;
1510 }
1511
1512 static int ip6gre_tunnel_init(struct net_device *dev)
1513 {
1514         struct ip6_tnl *tunnel;
1515         int ret;
1516
1517         ret = ip6gre_tunnel_init_common(dev);
1518         if (ret)
1519                 return ret;
1520
1521         tunnel = netdev_priv(dev);
1522
1523         if (tunnel->parms.collect_md)
1524                 return 0;
1525
1526         memcpy(dev->dev_addr, &tunnel->parms.laddr, sizeof(struct in6_addr));
1527         memcpy(dev->broadcast, &tunnel->parms.raddr, sizeof(struct in6_addr));
1528
1529         if (ipv6_addr_any(&tunnel->parms.raddr))
1530                 dev->header_ops = &ip6gre_header_ops;
1531
1532         return 0;
1533 }
1534
1535 static void ip6gre_fb_tunnel_init(struct net_device *dev)
1536 {
1537         struct ip6_tnl *tunnel = netdev_priv(dev);
1538
1539         tunnel->dev = dev;
1540         tunnel->net = dev_net(dev);
1541         strcpy(tunnel->parms.name, dev->name);
1542
1543         tunnel->hlen            = sizeof(struct ipv6hdr) + 4;
1544 }
1545
1546 static struct inet6_protocol ip6gre_protocol __read_mostly = {
1547         .handler     = gre_rcv,
1548         .err_handler = ip6gre_err,
1549         .flags       = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
1550 };
1551
1552 static void ip6gre_destroy_tunnels(struct net *net, struct list_head *head)
1553 {
1554         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1555         struct net_device *dev, *aux;
1556         int prio;
1557
1558         for_each_netdev_safe(net, dev, aux)
1559                 if (dev->rtnl_link_ops == &ip6gre_link_ops ||
1560                     dev->rtnl_link_ops == &ip6gre_tap_ops ||
1561                     dev->rtnl_link_ops == &ip6erspan_tap_ops)
1562                         unregister_netdevice_queue(dev, head);
1563
1564         for (prio = 0; prio < 4; prio++) {
1565                 int h;
1566                 for (h = 0; h < IP6_GRE_HASH_SIZE; h++) {
1567                         struct ip6_tnl *t;
1568
1569                         t = rtnl_dereference(ign->tunnels[prio][h]);
1570
1571                         while (t) {
1572                                 /* If dev is in the same netns, it has already
1573                                  * been added to the list by the previous loop.
1574                                  */
1575                                 if (!net_eq(dev_net(t->dev), net))
1576                                         unregister_netdevice_queue(t->dev,
1577                                                                    head);
1578                                 t = rtnl_dereference(t->next);
1579                         }
1580                 }
1581         }
1582 }
1583
1584 static int __net_init ip6gre_init_net(struct net *net)
1585 {
1586         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1587         struct net_device *ndev;
1588         int err;
1589
1590         if (!net_has_fallback_tunnels(net))
1591                 return 0;
1592         ndev = alloc_netdev(sizeof(struct ip6_tnl), "ip6gre0",
1593                             NET_NAME_UNKNOWN, ip6gre_tunnel_setup);
1594         if (!ndev) {
1595                 err = -ENOMEM;
1596                 goto err_alloc_dev;
1597         }
1598         ign->fb_tunnel_dev = ndev;
1599         dev_net_set(ign->fb_tunnel_dev, net);
1600         /* FB netdevice is special: we have one, and only one per netns.
1601          * Allowing to move it to another netns is clearly unsafe.
1602          */
1603         ign->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL;
1604
1605
1606         ip6gre_fb_tunnel_init(ign->fb_tunnel_dev);
1607         ign->fb_tunnel_dev->rtnl_link_ops = &ip6gre_link_ops;
1608
1609         err = register_netdev(ign->fb_tunnel_dev);
1610         if (err)
1611                 goto err_reg_dev;
1612
1613         rcu_assign_pointer(ign->tunnels_wc[0],
1614                            netdev_priv(ign->fb_tunnel_dev));
1615         return 0;
1616
1617 err_reg_dev:
1618         free_netdev(ndev);
1619 err_alloc_dev:
1620         return err;
1621 }
1622
1623 static void __net_exit ip6gre_exit_batch_net(struct list_head *net_list)
1624 {
1625         struct net *net;
1626         LIST_HEAD(list);
1627
1628         rtnl_lock();
1629         list_for_each_entry(net, net_list, exit_list)
1630                 ip6gre_destroy_tunnels(net, &list);
1631         unregister_netdevice_many(&list);
1632         rtnl_unlock();
1633 }
1634
1635 static struct pernet_operations ip6gre_net_ops = {
1636         .init = ip6gre_init_net,
1637         .exit_batch = ip6gre_exit_batch_net,
1638         .id   = &ip6gre_net_id,
1639         .size = sizeof(struct ip6gre_net),
1640 };
1641
1642 static int ip6gre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[],
1643                                   struct netlink_ext_ack *extack)
1644 {
1645         __be16 flags;
1646
1647         if (!data)
1648                 return 0;
1649
1650         flags = 0;
1651         if (data[IFLA_GRE_IFLAGS])
1652                 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
1653         if (data[IFLA_GRE_OFLAGS])
1654                 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
1655         if (flags & (GRE_VERSION|GRE_ROUTING))
1656                 return -EINVAL;
1657
1658         return 0;
1659 }
1660
1661 static int ip6gre_tap_validate(struct nlattr *tb[], struct nlattr *data[],
1662                                struct netlink_ext_ack *extack)
1663 {
1664         struct in6_addr daddr;
1665
1666         if (tb[IFLA_ADDRESS]) {
1667                 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
1668                         return -EINVAL;
1669                 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
1670                         return -EADDRNOTAVAIL;
1671         }
1672
1673         if (!data)
1674                 goto out;
1675
1676         if (data[IFLA_GRE_REMOTE]) {
1677                 daddr = nla_get_in6_addr(data[IFLA_GRE_REMOTE]);
1678                 if (ipv6_addr_any(&daddr))
1679                         return -EINVAL;
1680         }
1681
1682 out:
1683         return ip6gre_tunnel_validate(tb, data, extack);
1684 }
1685
1686 static int ip6erspan_tap_validate(struct nlattr *tb[], struct nlattr *data[],
1687                                   struct netlink_ext_ack *extack)
1688 {
1689         __be16 flags = 0;
1690         int ret, ver = 0;
1691
1692         if (!data)
1693                 return 0;
1694
1695         ret = ip6gre_tap_validate(tb, data, extack);
1696         if (ret)
1697                 return ret;
1698
1699         /* ERSPAN should only have GRE sequence and key flag */
1700         if (data[IFLA_GRE_OFLAGS])
1701                 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
1702         if (data[IFLA_GRE_IFLAGS])
1703                 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
1704         if (!data[IFLA_GRE_COLLECT_METADATA] &&
1705             flags != (GRE_SEQ | GRE_KEY))
1706                 return -EINVAL;
1707
1708         /* ERSPAN Session ID only has 10-bit. Since we reuse
1709          * 32-bit key field as ID, check it's range.
1710          */
1711         if (data[IFLA_GRE_IKEY] &&
1712             (ntohl(nla_get_be32(data[IFLA_GRE_IKEY])) & ~ID_MASK))
1713                 return -EINVAL;
1714
1715         if (data[IFLA_GRE_OKEY] &&
1716             (ntohl(nla_get_be32(data[IFLA_GRE_OKEY])) & ~ID_MASK))
1717                 return -EINVAL;
1718
1719         if (data[IFLA_GRE_ERSPAN_VER]) {
1720                 ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]);
1721                 if (ver != 1 && ver != 2)
1722                         return -EINVAL;
1723         }
1724
1725         if (ver == 1) {
1726                 if (data[IFLA_GRE_ERSPAN_INDEX]) {
1727                         u32 index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]);
1728
1729                         if (index & ~INDEX_MASK)
1730                                 return -EINVAL;
1731                 }
1732         } else if (ver == 2) {
1733                 if (data[IFLA_GRE_ERSPAN_DIR]) {
1734                         u16 dir = nla_get_u8(data[IFLA_GRE_ERSPAN_DIR]);
1735
1736                         if (dir & ~(DIR_MASK >> DIR_OFFSET))
1737                                 return -EINVAL;
1738                 }
1739
1740                 if (data[IFLA_GRE_ERSPAN_HWID]) {
1741                         u16 hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]);
1742
1743                         if (hwid & ~(HWID_MASK >> HWID_OFFSET))
1744                                 return -EINVAL;
1745                 }
1746         }
1747
1748         return 0;
1749 }
1750
1751 static void ip6erspan_set_version(struct nlattr *data[],
1752                                   struct __ip6_tnl_parm *parms)
1753 {
1754         if (!data)
1755                 return;
1756
1757         parms->erspan_ver = 1;
1758         if (data[IFLA_GRE_ERSPAN_VER])
1759                 parms->erspan_ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]);
1760
1761         if (parms->erspan_ver == 1) {
1762                 if (data[IFLA_GRE_ERSPAN_INDEX])
1763                         parms->index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]);
1764         } else if (parms->erspan_ver == 2) {
1765                 if (data[IFLA_GRE_ERSPAN_DIR])
1766                         parms->dir = nla_get_u8(data[IFLA_GRE_ERSPAN_DIR]);
1767                 if (data[IFLA_GRE_ERSPAN_HWID])
1768                         parms->hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]);
1769         }
1770 }
1771
1772 static void ip6gre_netlink_parms(struct nlattr *data[],
1773                                 struct __ip6_tnl_parm *parms)
1774 {
1775         memset(parms, 0, sizeof(*parms));
1776
1777         if (!data)
1778                 return;
1779
1780         if (data[IFLA_GRE_LINK])
1781                 parms->link = nla_get_u32(data[IFLA_GRE_LINK]);
1782
1783         if (data[IFLA_GRE_IFLAGS])
1784                 parms->i_flags = gre_flags_to_tnl_flags(
1785                                 nla_get_be16(data[IFLA_GRE_IFLAGS]));
1786
1787         if (data[IFLA_GRE_OFLAGS])
1788                 parms->o_flags = gre_flags_to_tnl_flags(
1789                                 nla_get_be16(data[IFLA_GRE_OFLAGS]));
1790
1791         if (data[IFLA_GRE_IKEY])
1792                 parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]);
1793
1794         if (data[IFLA_GRE_OKEY])
1795                 parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]);
1796
1797         if (data[IFLA_GRE_LOCAL])
1798                 parms->laddr = nla_get_in6_addr(data[IFLA_GRE_LOCAL]);
1799
1800         if (data[IFLA_GRE_REMOTE])
1801                 parms->raddr = nla_get_in6_addr(data[IFLA_GRE_REMOTE]);
1802
1803         if (data[IFLA_GRE_TTL])
1804                 parms->hop_limit = nla_get_u8(data[IFLA_GRE_TTL]);
1805
1806         if (data[IFLA_GRE_ENCAP_LIMIT])
1807                 parms->encap_limit = nla_get_u8(data[IFLA_GRE_ENCAP_LIMIT]);
1808
1809         if (data[IFLA_GRE_FLOWINFO])
1810                 parms->flowinfo = nla_get_be32(data[IFLA_GRE_FLOWINFO]);
1811
1812         if (data[IFLA_GRE_FLAGS])
1813                 parms->flags = nla_get_u32(data[IFLA_GRE_FLAGS]);
1814
1815         if (data[IFLA_GRE_FWMARK])
1816                 parms->fwmark = nla_get_u32(data[IFLA_GRE_FWMARK]);
1817
1818         if (data[IFLA_GRE_COLLECT_METADATA])
1819                 parms->collect_md = true;
1820 }
1821
1822 static int ip6gre_tap_init(struct net_device *dev)
1823 {
1824         int ret;
1825
1826         ret = ip6gre_tunnel_init_common(dev);
1827         if (ret)
1828                 return ret;
1829
1830         dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1831
1832         return 0;
1833 }
1834
1835 static const struct net_device_ops ip6gre_tap_netdev_ops = {
1836         .ndo_init = ip6gre_tap_init,
1837         .ndo_uninit = ip6gre_tunnel_uninit,
1838         .ndo_start_xmit = ip6gre_tunnel_xmit,
1839         .ndo_set_mac_address = eth_mac_addr,
1840         .ndo_validate_addr = eth_validate_addr,
1841         .ndo_change_mtu = ip6_tnl_change_mtu,
1842         .ndo_get_stats64 = dev_get_tstats64,
1843         .ndo_get_iflink = ip6_tnl_get_iflink,
1844 };
1845
1846 static int ip6erspan_calc_hlen(struct ip6_tnl *tunnel)
1847 {
1848         int t_hlen;
1849
1850         tunnel->tun_hlen = 8;
1851         tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen +
1852                        erspan_hdr_len(tunnel->parms.erspan_ver);
1853
1854         t_hlen = tunnel->hlen + sizeof(struct ipv6hdr);
1855         tunnel->dev->needed_headroom = LL_MAX_HEADER + t_hlen;
1856         return t_hlen;
1857 }
1858
1859 static int ip6erspan_tap_init(struct net_device *dev)
1860 {
1861         struct ip6_tnl *tunnel;
1862         int t_hlen;
1863         int ret;
1864
1865         tunnel = netdev_priv(dev);
1866
1867         tunnel->dev = dev;
1868         tunnel->net = dev_net(dev);
1869         strcpy(tunnel->parms.name, dev->name);
1870
1871         dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1872         if (!dev->tstats)
1873                 return -ENOMEM;
1874
1875         ret = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
1876         if (ret)
1877                 goto cleanup_alloc_pcpu_stats;
1878
1879         ret = gro_cells_init(&tunnel->gro_cells, dev);
1880         if (ret)
1881                 goto cleanup_dst_cache_init;
1882
1883         t_hlen = ip6erspan_calc_hlen(tunnel);
1884         dev->mtu = ETH_DATA_LEN - t_hlen;
1885         if (dev->type == ARPHRD_ETHER)
1886                 dev->mtu -= ETH_HLEN;
1887         if (!(tunnel->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1888                 dev->mtu -= 8;
1889
1890         dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1891         ip6erspan_tnl_link_config(tunnel, 1);
1892
1893         dev_hold(dev);
1894         return 0;
1895
1896 cleanup_dst_cache_init:
1897         dst_cache_destroy(&tunnel->dst_cache);
1898 cleanup_alloc_pcpu_stats:
1899         free_percpu(dev->tstats);
1900         dev->tstats = NULL;
1901         return ret;
1902 }
1903
1904 static const struct net_device_ops ip6erspan_netdev_ops = {
1905         .ndo_init =             ip6erspan_tap_init,
1906         .ndo_uninit =           ip6erspan_tunnel_uninit,
1907         .ndo_start_xmit =       ip6erspan_tunnel_xmit,
1908         .ndo_set_mac_address =  eth_mac_addr,
1909         .ndo_validate_addr =    eth_validate_addr,
1910         .ndo_change_mtu =       ip6_tnl_change_mtu,
1911         .ndo_get_stats64 =      dev_get_tstats64,
1912         .ndo_get_iflink =       ip6_tnl_get_iflink,
1913 };
1914
1915 static void ip6gre_tap_setup(struct net_device *dev)
1916 {
1917
1918         ether_setup(dev);
1919
1920         dev->max_mtu = 0;
1921         dev->netdev_ops = &ip6gre_tap_netdev_ops;
1922         dev->needs_free_netdev = true;
1923         dev->priv_destructor = ip6gre_dev_free;
1924
1925         dev->priv_flags &= ~IFF_TX_SKB_SHARING;
1926         dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1927         netif_keep_dst(dev);
1928 }
1929
1930 static bool ip6gre_netlink_encap_parms(struct nlattr *data[],
1931                                        struct ip_tunnel_encap *ipencap)
1932 {
1933         bool ret = false;
1934
1935         memset(ipencap, 0, sizeof(*ipencap));
1936
1937         if (!data)
1938                 return ret;
1939
1940         if (data[IFLA_GRE_ENCAP_TYPE]) {
1941                 ret = true;
1942                 ipencap->type = nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]);
1943         }
1944
1945         if (data[IFLA_GRE_ENCAP_FLAGS]) {
1946                 ret = true;
1947                 ipencap->flags = nla_get_u16(data[IFLA_GRE_ENCAP_FLAGS]);
1948         }
1949
1950         if (data[IFLA_GRE_ENCAP_SPORT]) {
1951                 ret = true;
1952                 ipencap->sport = nla_get_be16(data[IFLA_GRE_ENCAP_SPORT]);
1953         }
1954
1955         if (data[IFLA_GRE_ENCAP_DPORT]) {
1956                 ret = true;
1957                 ipencap->dport = nla_get_be16(data[IFLA_GRE_ENCAP_DPORT]);
1958         }
1959
1960         return ret;
1961 }
1962
1963 static int ip6gre_newlink_common(struct net *src_net, struct net_device *dev,
1964                                  struct nlattr *tb[], struct nlattr *data[],
1965                                  struct netlink_ext_ack *extack)
1966 {
1967         struct ip6_tnl *nt;
1968         struct ip_tunnel_encap ipencap;
1969         int err;
1970
1971         nt = netdev_priv(dev);
1972
1973         if (ip6gre_netlink_encap_parms(data, &ipencap)) {
1974                 int err = ip6_tnl_encap_setup(nt, &ipencap);
1975
1976                 if (err < 0)
1977                         return err;
1978         }
1979
1980         if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS])
1981                 eth_hw_addr_random(dev);
1982
1983         nt->dev = dev;
1984         nt->net = dev_net(dev);
1985
1986         err = register_netdevice(dev);
1987         if (err)
1988                 goto out;
1989
1990         if (tb[IFLA_MTU])
1991                 ip6_tnl_change_mtu(dev, nla_get_u32(tb[IFLA_MTU]));
1992
1993 out:
1994         return err;
1995 }
1996
1997 static int ip6gre_newlink(struct net *src_net, struct net_device *dev,
1998                           struct nlattr *tb[], struct nlattr *data[],
1999                           struct netlink_ext_ack *extack)
2000 {
2001         struct ip6_tnl *nt = netdev_priv(dev);
2002         struct net *net = dev_net(dev);
2003         struct ip6gre_net *ign;
2004         int err;
2005
2006         ip6gre_netlink_parms(data, &nt->parms);
2007         ign = net_generic(net, ip6gre_net_id);
2008
2009         if (nt->parms.collect_md) {
2010                 if (rtnl_dereference(ign->collect_md_tun))
2011                         return -EEXIST;
2012         } else {
2013                 if (ip6gre_tunnel_find(net, &nt->parms, dev->type))
2014                         return -EEXIST;
2015         }
2016
2017         err = ip6gre_newlink_common(src_net, dev, tb, data, extack);
2018         if (!err) {
2019                 ip6gre_tnl_link_config(nt, !tb[IFLA_MTU]);
2020                 ip6gre_tunnel_link_md(ign, nt);
2021                 ip6gre_tunnel_link(net_generic(net, ip6gre_net_id), nt);
2022         }
2023         return err;
2024 }
2025
2026 static struct ip6_tnl *
2027 ip6gre_changelink_common(struct net_device *dev, struct nlattr *tb[],
2028                          struct nlattr *data[], struct __ip6_tnl_parm *p_p,
2029                          struct netlink_ext_ack *extack)
2030 {
2031         struct ip6_tnl *t, *nt = netdev_priv(dev);
2032         struct net *net = nt->net;
2033         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
2034         struct ip_tunnel_encap ipencap;
2035
2036         if (dev == ign->fb_tunnel_dev)
2037                 return ERR_PTR(-EINVAL);
2038
2039         if (ip6gre_netlink_encap_parms(data, &ipencap)) {
2040                 int err = ip6_tnl_encap_setup(nt, &ipencap);
2041
2042                 if (err < 0)
2043                         return ERR_PTR(err);
2044         }
2045
2046         ip6gre_netlink_parms(data, p_p);
2047
2048         t = ip6gre_tunnel_locate(net, p_p, 0);
2049
2050         if (t) {
2051                 if (t->dev != dev)
2052                         return ERR_PTR(-EEXIST);
2053         } else {
2054                 t = nt;
2055         }
2056
2057         return t;
2058 }
2059
2060 static int ip6gre_changelink(struct net_device *dev, struct nlattr *tb[],
2061                              struct nlattr *data[],
2062                              struct netlink_ext_ack *extack)
2063 {
2064         struct ip6_tnl *t = netdev_priv(dev);
2065         struct ip6gre_net *ign = net_generic(t->net, ip6gre_net_id);
2066         struct __ip6_tnl_parm p;
2067
2068         t = ip6gre_changelink_common(dev, tb, data, &p, extack);
2069         if (IS_ERR(t))
2070                 return PTR_ERR(t);
2071
2072         ip6gre_tunnel_unlink_md(ign, t);
2073         ip6gre_tunnel_unlink(ign, t);
2074         ip6gre_tnl_change(t, &p, !tb[IFLA_MTU]);
2075         ip6gre_tunnel_link_md(ign, t);
2076         ip6gre_tunnel_link(ign, t);
2077         return 0;
2078 }
2079
2080 static void ip6gre_dellink(struct net_device *dev, struct list_head *head)
2081 {
2082         struct net *net = dev_net(dev);
2083         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
2084
2085         if (dev != ign->fb_tunnel_dev)
2086                 unregister_netdevice_queue(dev, head);
2087 }
2088
2089 static size_t ip6gre_get_size(const struct net_device *dev)
2090 {
2091         return
2092                 /* IFLA_GRE_LINK */
2093                 nla_total_size(4) +
2094                 /* IFLA_GRE_IFLAGS */
2095                 nla_total_size(2) +
2096                 /* IFLA_GRE_OFLAGS */
2097                 nla_total_size(2) +
2098                 /* IFLA_GRE_IKEY */
2099                 nla_total_size(4) +
2100                 /* IFLA_GRE_OKEY */
2101                 nla_total_size(4) +
2102                 /* IFLA_GRE_LOCAL */
2103                 nla_total_size(sizeof(struct in6_addr)) +
2104                 /* IFLA_GRE_REMOTE */
2105                 nla_total_size(sizeof(struct in6_addr)) +
2106                 /* IFLA_GRE_TTL */
2107                 nla_total_size(1) +
2108                 /* IFLA_GRE_ENCAP_LIMIT */
2109                 nla_total_size(1) +
2110                 /* IFLA_GRE_FLOWINFO */
2111                 nla_total_size(4) +
2112                 /* IFLA_GRE_FLAGS */
2113                 nla_total_size(4) +
2114                 /* IFLA_GRE_ENCAP_TYPE */
2115                 nla_total_size(2) +
2116                 /* IFLA_GRE_ENCAP_FLAGS */
2117                 nla_total_size(2) +
2118                 /* IFLA_GRE_ENCAP_SPORT */
2119                 nla_total_size(2) +
2120                 /* IFLA_GRE_ENCAP_DPORT */
2121                 nla_total_size(2) +
2122                 /* IFLA_GRE_COLLECT_METADATA */
2123                 nla_total_size(0) +
2124                 /* IFLA_GRE_FWMARK */
2125                 nla_total_size(4) +
2126                 /* IFLA_GRE_ERSPAN_INDEX */
2127                 nla_total_size(4) +
2128                 0;
2129 }
2130
2131 static int ip6gre_fill_info(struct sk_buff *skb, const struct net_device *dev)
2132 {
2133         struct ip6_tnl *t = netdev_priv(dev);
2134         struct __ip6_tnl_parm *p = &t->parms;
2135         __be16 o_flags = p->o_flags;
2136
2137         if (p->erspan_ver == 1 || p->erspan_ver == 2) {
2138                 if (!p->collect_md)
2139                         o_flags |= TUNNEL_KEY;
2140
2141                 if (nla_put_u8(skb, IFLA_GRE_ERSPAN_VER, p->erspan_ver))
2142                         goto nla_put_failure;
2143
2144                 if (p->erspan_ver == 1) {
2145                         if (nla_put_u32(skb, IFLA_GRE_ERSPAN_INDEX, p->index))
2146                                 goto nla_put_failure;
2147                 } else {
2148                         if (nla_put_u8(skb, IFLA_GRE_ERSPAN_DIR, p->dir))
2149                                 goto nla_put_failure;
2150                         if (nla_put_u16(skb, IFLA_GRE_ERSPAN_HWID, p->hwid))
2151                                 goto nla_put_failure;
2152                 }
2153         }
2154
2155         if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) ||
2156             nla_put_be16(skb, IFLA_GRE_IFLAGS,
2157                          gre_tnl_flags_to_gre_flags(p->i_flags)) ||
2158             nla_put_be16(skb, IFLA_GRE_OFLAGS,
2159                          gre_tnl_flags_to_gre_flags(o_flags)) ||
2160             nla_put_be32(skb, IFLA_GRE_IKEY, p->i_key) ||
2161             nla_put_be32(skb, IFLA_GRE_OKEY, p->o_key) ||
2162             nla_put_in6_addr(skb, IFLA_GRE_LOCAL, &p->laddr) ||
2163             nla_put_in6_addr(skb, IFLA_GRE_REMOTE, &p->raddr) ||
2164             nla_put_u8(skb, IFLA_GRE_TTL, p->hop_limit) ||
2165             nla_put_u8(skb, IFLA_GRE_ENCAP_LIMIT, p->encap_limit) ||
2166             nla_put_be32(skb, IFLA_GRE_FLOWINFO, p->flowinfo) ||
2167             nla_put_u32(skb, IFLA_GRE_FLAGS, p->flags) ||
2168             nla_put_u32(skb, IFLA_GRE_FWMARK, p->fwmark))
2169                 goto nla_put_failure;
2170
2171         if (nla_put_u16(skb, IFLA_GRE_ENCAP_TYPE,
2172                         t->encap.type) ||
2173             nla_put_be16(skb, IFLA_GRE_ENCAP_SPORT,
2174                          t->encap.sport) ||
2175             nla_put_be16(skb, IFLA_GRE_ENCAP_DPORT,
2176                          t->encap.dport) ||
2177             nla_put_u16(skb, IFLA_GRE_ENCAP_FLAGS,
2178                         t->encap.flags))
2179                 goto nla_put_failure;
2180
2181         if (p->collect_md) {
2182                 if (nla_put_flag(skb, IFLA_GRE_COLLECT_METADATA))
2183                         goto nla_put_failure;
2184         }
2185
2186         return 0;
2187
2188 nla_put_failure:
2189         return -EMSGSIZE;
2190 }
2191
2192 static const struct nla_policy ip6gre_policy[IFLA_GRE_MAX + 1] = {
2193         [IFLA_GRE_LINK]        = { .type = NLA_U32 },
2194         [IFLA_GRE_IFLAGS]      = { .type = NLA_U16 },
2195         [IFLA_GRE_OFLAGS]      = { .type = NLA_U16 },
2196         [IFLA_GRE_IKEY]        = { .type = NLA_U32 },
2197         [IFLA_GRE_OKEY]        = { .type = NLA_U32 },
2198         [IFLA_GRE_LOCAL]       = { .len = sizeof_field(struct ipv6hdr, saddr) },
2199         [IFLA_GRE_REMOTE]      = { .len = sizeof_field(struct ipv6hdr, daddr) },
2200         [IFLA_GRE_TTL]         = { .type = NLA_U8 },
2201         [IFLA_GRE_ENCAP_LIMIT] = { .type = NLA_U8 },
2202         [IFLA_GRE_FLOWINFO]    = { .type = NLA_U32 },
2203         [IFLA_GRE_FLAGS]       = { .type = NLA_U32 },
2204         [IFLA_GRE_ENCAP_TYPE]   = { .type = NLA_U16 },
2205         [IFLA_GRE_ENCAP_FLAGS]  = { .type = NLA_U16 },
2206         [IFLA_GRE_ENCAP_SPORT]  = { .type = NLA_U16 },
2207         [IFLA_GRE_ENCAP_DPORT]  = { .type = NLA_U16 },
2208         [IFLA_GRE_COLLECT_METADATA] = { .type = NLA_FLAG },
2209         [IFLA_GRE_FWMARK]       = { .type = NLA_U32 },
2210         [IFLA_GRE_ERSPAN_INDEX] = { .type = NLA_U32 },
2211         [IFLA_GRE_ERSPAN_VER]   = { .type = NLA_U8 },
2212         [IFLA_GRE_ERSPAN_DIR]   = { .type = NLA_U8 },
2213         [IFLA_GRE_ERSPAN_HWID]  = { .type = NLA_U16 },
2214 };
2215
2216 static void ip6erspan_tap_setup(struct net_device *dev)
2217 {
2218         ether_setup(dev);
2219
2220         dev->max_mtu = 0;
2221         dev->netdev_ops = &ip6erspan_netdev_ops;
2222         dev->needs_free_netdev = true;
2223         dev->priv_destructor = ip6gre_dev_free;
2224
2225         dev->priv_flags &= ~IFF_TX_SKB_SHARING;
2226         dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
2227         netif_keep_dst(dev);
2228 }
2229
2230 static int ip6erspan_newlink(struct net *src_net, struct net_device *dev,
2231                              struct nlattr *tb[], struct nlattr *data[],
2232                              struct netlink_ext_ack *extack)
2233 {
2234         struct ip6_tnl *nt = netdev_priv(dev);
2235         struct net *net = dev_net(dev);
2236         struct ip6gre_net *ign;
2237         int err;
2238
2239         ip6gre_netlink_parms(data, &nt->parms);
2240         ip6erspan_set_version(data, &nt->parms);
2241         ign = net_generic(net, ip6gre_net_id);
2242
2243         if (nt->parms.collect_md) {
2244                 if (rtnl_dereference(ign->collect_md_tun_erspan))
2245                         return -EEXIST;
2246         } else {
2247                 if (ip6gre_tunnel_find(net, &nt->parms, dev->type))
2248                         return -EEXIST;
2249         }
2250
2251         err = ip6gre_newlink_common(src_net, dev, tb, data, extack);
2252         if (!err) {
2253                 ip6erspan_tnl_link_config(nt, !tb[IFLA_MTU]);
2254                 ip6erspan_tunnel_link_md(ign, nt);
2255                 ip6gre_tunnel_link(net_generic(net, ip6gre_net_id), nt);
2256         }
2257         return err;
2258 }
2259
2260 static void ip6erspan_tnl_link_config(struct ip6_tnl *t, int set_mtu)
2261 {
2262         ip6gre_tnl_link_config_common(t);
2263         ip6gre_tnl_link_config_route(t, set_mtu, ip6erspan_calc_hlen(t));
2264 }
2265
2266 static int ip6erspan_tnl_change(struct ip6_tnl *t,
2267                                 const struct __ip6_tnl_parm *p, int set_mtu)
2268 {
2269         ip6gre_tnl_copy_tnl_parm(t, p);
2270         ip6erspan_tnl_link_config(t, set_mtu);
2271         return 0;
2272 }
2273
2274 static int ip6erspan_changelink(struct net_device *dev, struct nlattr *tb[],
2275                                 struct nlattr *data[],
2276                                 struct netlink_ext_ack *extack)
2277 {
2278         struct ip6gre_net *ign = net_generic(dev_net(dev), ip6gre_net_id);
2279         struct __ip6_tnl_parm p;
2280         struct ip6_tnl *t;
2281
2282         t = ip6gre_changelink_common(dev, tb, data, &p, extack);
2283         if (IS_ERR(t))
2284                 return PTR_ERR(t);
2285
2286         ip6erspan_set_version(data, &p);
2287         ip6gre_tunnel_unlink_md(ign, t);
2288         ip6gre_tunnel_unlink(ign, t);
2289         ip6erspan_tnl_change(t, &p, !tb[IFLA_MTU]);
2290         ip6erspan_tunnel_link_md(ign, t);
2291         ip6gre_tunnel_link(ign, t);
2292         return 0;
2293 }
2294
2295 static struct rtnl_link_ops ip6gre_link_ops __read_mostly = {
2296         .kind           = "ip6gre",
2297         .maxtype        = IFLA_GRE_MAX,
2298         .policy         = ip6gre_policy,
2299         .priv_size      = sizeof(struct ip6_tnl),
2300         .setup          = ip6gre_tunnel_setup,
2301         .validate       = ip6gre_tunnel_validate,
2302         .newlink        = ip6gre_newlink,
2303         .changelink     = ip6gre_changelink,
2304         .dellink        = ip6gre_dellink,
2305         .get_size       = ip6gre_get_size,
2306         .fill_info      = ip6gre_fill_info,
2307         .get_link_net   = ip6_tnl_get_link_net,
2308 };
2309
2310 static struct rtnl_link_ops ip6gre_tap_ops __read_mostly = {
2311         .kind           = "ip6gretap",
2312         .maxtype        = IFLA_GRE_MAX,
2313         .policy         = ip6gre_policy,
2314         .priv_size      = sizeof(struct ip6_tnl),
2315         .setup          = ip6gre_tap_setup,
2316         .validate       = ip6gre_tap_validate,
2317         .newlink        = ip6gre_newlink,
2318         .changelink     = ip6gre_changelink,
2319         .get_size       = ip6gre_get_size,
2320         .fill_info      = ip6gre_fill_info,
2321         .get_link_net   = ip6_tnl_get_link_net,
2322 };
2323
2324 static struct rtnl_link_ops ip6erspan_tap_ops __read_mostly = {
2325         .kind           = "ip6erspan",
2326         .maxtype        = IFLA_GRE_MAX,
2327         .policy         = ip6gre_policy,
2328         .priv_size      = sizeof(struct ip6_tnl),
2329         .setup          = ip6erspan_tap_setup,
2330         .validate       = ip6erspan_tap_validate,
2331         .newlink        = ip6erspan_newlink,
2332         .changelink     = ip6erspan_changelink,
2333         .get_size       = ip6gre_get_size,
2334         .fill_info      = ip6gre_fill_info,
2335         .get_link_net   = ip6_tnl_get_link_net,
2336 };
2337
2338 /*
2339  *      And now the modules code and kernel interface.
2340  */
2341
2342 static int __init ip6gre_init(void)
2343 {
2344         int err;
2345
2346         pr_info("GRE over IPv6 tunneling driver\n");
2347
2348         err = register_pernet_device(&ip6gre_net_ops);
2349         if (err < 0)
2350                 return err;
2351
2352         err = inet6_add_protocol(&ip6gre_protocol, IPPROTO_GRE);
2353         if (err < 0) {
2354                 pr_info("%s: can't add protocol\n", __func__);
2355                 goto add_proto_failed;
2356         }
2357
2358         err = rtnl_link_register(&ip6gre_link_ops);
2359         if (err < 0)
2360                 goto rtnl_link_failed;
2361
2362         err = rtnl_link_register(&ip6gre_tap_ops);
2363         if (err < 0)
2364                 goto tap_ops_failed;
2365
2366         err = rtnl_link_register(&ip6erspan_tap_ops);
2367         if (err < 0)
2368                 goto erspan_link_failed;
2369
2370 out:
2371         return err;
2372
2373 erspan_link_failed:
2374         rtnl_link_unregister(&ip6gre_tap_ops);
2375 tap_ops_failed:
2376         rtnl_link_unregister(&ip6gre_link_ops);
2377 rtnl_link_failed:
2378         inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE);
2379 add_proto_failed:
2380         unregister_pernet_device(&ip6gre_net_ops);
2381         goto out;
2382 }
2383
2384 static void __exit ip6gre_fini(void)
2385 {
2386         rtnl_link_unregister(&ip6gre_tap_ops);
2387         rtnl_link_unregister(&ip6gre_link_ops);
2388         rtnl_link_unregister(&ip6erspan_tap_ops);
2389         inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE);
2390         unregister_pernet_device(&ip6gre_net_ops);
2391 }
2392
2393 module_init(ip6gre_init);
2394 module_exit(ip6gre_fini);
2395 MODULE_LICENSE("GPL");
2396 MODULE_AUTHOR("D. Kozlov (xeb@mail.ru)");
2397 MODULE_DESCRIPTION("GRE over IPv6 tunneling device");
2398 MODULE_ALIAS_RTNL_LINK("ip6gre");
2399 MODULE_ALIAS_RTNL_LINK("ip6gretap");
2400 MODULE_ALIAS_RTNL_LINK("ip6erspan");
2401 MODULE_ALIAS_NETDEV("ip6gre0");