net/ipv6/ip6_gre.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *      GRE over IPv6 protocol decoder.
   4  *
   5  *      Authors: Dmitry Kozlov (xeb@mail.ru)
   6  */
   7
   8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
   9
  10 #include <linux/capability.h>
  11 #include <linux/module.h>
  12 #include <linux/types.h>
  13 #include <linux/kernel.h>
  14 #include <linux/slab.h>
  15 #include <linux/uaccess.h>
  16 #include <linux/skbuff.h>
  17 #include <linux/netdevice.h>
  18 #include <linux/in.h>
  19 #include <linux/tcp.h>
  20 #include <linux/udp.h>
  21 #include <linux/if_arp.h>
  22 #include <linux/init.h>
  23 #include <linux/in6.h>
  24 #include <linux/inetdevice.h>
  25 #include <linux/igmp.h>
  26 #include <linux/netfilter_ipv4.h>
  27 #include <linux/etherdevice.h>
  28 #include <linux/if_ether.h>
  29 #include <linux/hash.h>
  30 #include <linux/if_tunnel.h>
  31 #include <linux/ip6_tunnel.h>
  32
  33 #include <net/sock.h>
  34 #include <net/ip.h>
  35 #include <net/ip_tunnels.h>
  36 #include <net/icmp.h>
  37 #include <net/protocol.h>
  38 #include <net/addrconf.h>
  39 #include <net/arp.h>
  40 #include <net/checksum.h>
  41 #include <net/dsfield.h>
  42 #include <net/inet_ecn.h>
  43 #include <net/xfrm.h>
  44 #include <net/net_namespace.h>
  45 #include <net/netns/generic.h>
  46 #include <net/rtnetlink.h>
  47
  48 #include <net/ipv6.h>
  49 #include <net/ip6_fib.h>
  50 #include <net/ip6_route.h>
  51 #include <net/ip6_tunnel.h>
  52 #include <net/gre.h>
  53 #include <net/erspan.h>
  54 #include <net/dst_metadata.h>
  55
  56
  57 static bool log_ecn_error = true;
  58 module_param(log_ecn_error, bool, 0644);
  59 MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");
  60
  61 #define IP6_GRE_HASH_SIZE_SHIFT  5
  62 #define IP6_GRE_HASH_SIZE (1 << IP6_GRE_HASH_SIZE_SHIFT)
  63
  64 static unsigned int ip6gre_net_id __read_mostly;
  65 struct ip6gre_net {
  66         struct ip6_tnl __rcu *tunnels[4][IP6_GRE_HASH_SIZE];
  67
  68         struct ip6_tnl __rcu *collect_md_tun;
  69         struct ip6_tnl __rcu *collect_md_tun_erspan;
  70         struct net_device *fb_tunnel_dev;
  71 };
  72
  73 static struct rtnl_link_ops ip6gre_link_ops __read_mostly;
  74 static struct rtnl_link_ops ip6gre_tap_ops __read_mostly;
  75 static struct rtnl_link_ops ip6erspan_tap_ops __read_mostly;
  76 static int ip6gre_tunnel_init(struct net_device *dev);
  77 static void ip6gre_tunnel_setup(struct net_device *dev);
  78 static void ip6gre_tunnel_link(struct ip6gre_net *ign, struct ip6_tnl *t);
  79 static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu);
  80 static void ip6erspan_tnl_link_config(struct ip6_tnl *t, int set_mtu);
  81
  82 /* Tunnel hash table */
  83
  84 /*
  85    4 hash tables:
  86
  87    3: (remote,local)
  88    2: (remote,*)
  89    1: (*,local)
  90    0: (*,*)
  91
  92    We require exact key match i.e. if a key is present in packet
  93    it will match only tunnel with the same key; if it is not present,
  94    it will match only keyless tunnel.
  95
  96    All keysless packets, if not matched configured keyless tunnels
  97    will match fallback tunnel.
  98  */
  99
 100 #define HASH_KEY(key) (((__force u32)key^((__force u32)key>>4))&(IP6_GRE_HASH_SIZE - 1))
 101 static u32 HASH_ADDR(const struct in6_addr *addr)
 102 {
 103         u32 hash = ipv6_addr_hash(addr);
 104
 105         return hash_32(hash, IP6_GRE_HASH_SIZE_SHIFT);
 106 }
 107
 108 #define tunnels_r_l     tunnels[3]
 109 #define tunnels_r       tunnels[2]
 110 #define tunnels_l       tunnels[1]
 111 #define tunnels_wc      tunnels[0]
 112
 113 /* Given src, dst and key, find appropriate for input tunnel. */
 114
 115 static struct ip6_tnl *ip6gre_tunnel_lookup(struct net_device *dev,
 116                 const struct in6_addr *remote, const struct in6_addr *local,
 117                 __be32 key, __be16 gre_proto)
 118 {
 119         struct net *net = dev_net(dev);
 120         int link = dev->ifindex;
 121         unsigned int h0 = HASH_ADDR(remote);
 122         unsigned int h1 = HASH_KEY(key);
 123         struct ip6_tnl *t, *cand = NULL;
 124         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
 125         int dev_type = (gre_proto == htons(ETH_P_TEB) ||
 126                         gre_proto == htons(ETH_P_ERSPAN) ||
 127                         gre_proto == htons(ETH_P_ERSPAN2)) ?
 128                        ARPHRD_ETHER : ARPHRD_IP6GRE;
 129         int score, cand_score = 4;
 130         struct net_device *ndev;
 131
 132         for_each_ip_tunnel_rcu(t, ign->tunnels_r_l[h0 ^ h1]) {
 133                 if (!ipv6_addr_equal(local, &t->parms.laddr) ||
 134                     !ipv6_addr_equal(remote, &t->parms.raddr) ||
 135                     key != t->parms.i_key ||
 136                     !(t->dev->flags & IFF_UP))
 137                         continue;
 138
 139                 if (t->dev->type != ARPHRD_IP6GRE &&
 140                     t->dev->type != dev_type)
 141                         continue;
 142
 143                 score = 0;
 144                 if (t->parms.link != link)
 145                         score |= 1;
 146                 if (t->dev->type != dev_type)
 147                         score |= 2;
 148                 if (score == 0)
 149                         return t;
 150
 151                 if (score < cand_score) {
 152                         cand = t;
 153                         cand_score = score;
 154                 }
 155         }
 156
 157         for_each_ip_tunnel_rcu(t, ign->tunnels_r[h0 ^ h1]) {
 158                 if (!ipv6_addr_equal(remote, &t->parms.raddr) ||
 159                     key != t->parms.i_key ||
 160                     !(t->dev->flags & IFF_UP))
 161                         continue;
 162
 163                 if (t->dev->type != ARPHRD_IP6GRE &&
 164                     t->dev->type != dev_type)
 165                         continue;
 166
 167                 score = 0;
 168                 if (t->parms.link != link)
 169                         score |= 1;
 170                 if (t->dev->type != dev_type)
 171                         score |= 2;
 172                 if (score == 0)
 173                         return t;
 174
 175                 if (score < cand_score) {
 176                         cand = t;
 177                         cand_score = score;
 178                 }
 179         }
 180
 181         for_each_ip_tunnel_rcu(t, ign->tunnels_l[h1]) {
 182                 if ((!ipv6_addr_equal(local, &t->parms.laddr) &&
 183                           (!ipv6_addr_equal(local, &t->parms.raddr) ||
 184                                  !ipv6_addr_is_multicast(local))) ||
 185                     key != t->parms.i_key ||
 186                     !(t->dev->flags & IFF_UP))
 187                         continue;
 188
 189                 if (t->dev->type != ARPHRD_IP6GRE &&
 190                     t->dev->type != dev_type)
 191                         continue;
 192
 193                 score = 0;
 194                 if (t->parms.link != link)
 195                         score |= 1;
 196                 if (t->dev->type != dev_type)
 197                         score |= 2;
 198                 if (score == 0)
 199                         return t;
 200
 201                 if (score < cand_score) {
 202                         cand = t;
 203                         cand_score = score;
 204                 }
 205         }
 206
 207         for_each_ip_tunnel_rcu(t, ign->tunnels_wc[h1]) {
 208                 if (t->parms.i_key != key ||
 209                     !(t->dev->flags & IFF_UP))
 210                         continue;
 211
 212                 if (t->dev->type != ARPHRD_IP6GRE &&
 213                     t->dev->type != dev_type)
 214                         continue;
 215
 216                 score = 0;
 217                 if (t->parms.link != link)
 218                         score |= 1;
 219                 if (t->dev->type != dev_type)
 220                         score |= 2;
 221                 if (score == 0)
 222                         return t;
 223
 224                 if (score < cand_score) {
 225                         cand = t;
 226                         cand_score = score;
 227                 }
 228         }
 229
 230         if (cand)
 231                 return cand;
 232
 233         if (gre_proto == htons(ETH_P_ERSPAN) ||
 234             gre_proto == htons(ETH_P_ERSPAN2))
 235                 t = rcu_dereference(ign->collect_md_tun_erspan);
 236         else
 237                 t = rcu_dereference(ign->collect_md_tun);
 238
 239         if (t && t->dev->flags & IFF_UP)
 240                 return t;
 241
 242         ndev = READ_ONCE(ign->fb_tunnel_dev);
 243         if (ndev && ndev->flags & IFF_UP)
 244                 return netdev_priv(ndev);
 245
 246         return NULL;
 247 }
 248
 249 static struct ip6_tnl __rcu **__ip6gre_bucket(struct ip6gre_net *ign,
 250                 const struct __ip6_tnl_parm *p)
 251 {
 252         const struct in6_addr *remote = &p->raddr;
 253         const struct in6_addr *local = &p->laddr;
 254         unsigned int h = HASH_KEY(p->i_key);
 255         int prio = 0;
 256
 257         if (!ipv6_addr_any(local))
 258                 prio |= 1;
 259         if (!ipv6_addr_any(remote) && !ipv6_addr_is_multicast(remote)) {
 260                 prio |= 2;
 261                 h ^= HASH_ADDR(remote);
 262         }
 263
 264         return &ign->tunnels[prio][h];
 265 }
 266
 267 static void ip6gre_tunnel_link_md(struct ip6gre_net *ign, struct ip6_tnl *t)
 268 {
 269         if (t->parms.collect_md)
 270                 rcu_assign_pointer(ign->collect_md_tun, t);
 271 }
 272
 273 static void ip6erspan_tunnel_link_md(struct ip6gre_net *ign, struct ip6_tnl *t)
 274 {
 275         if (t->parms.collect_md)
 276                 rcu_assign_pointer(ign->collect_md_tun_erspan, t);
 277 }
 278
 279 static void ip6gre_tunnel_unlink_md(struct ip6gre_net *ign, struct ip6_tnl *t)
 280 {
 281         if (t->parms.collect_md)
 282                 rcu_assign_pointer(ign->collect_md_tun, NULL);
 283 }
 284
 285 static void ip6erspan_tunnel_unlink_md(struct ip6gre_net *ign,
 286                                        struct ip6_tnl *t)
 287 {
 288         if (t->parms.collect_md)
 289                 rcu_assign_pointer(ign->collect_md_tun_erspan, NULL);
 290 }
 291
 292 static inline struct ip6_tnl __rcu **ip6gre_bucket(struct ip6gre_net *ign,
 293                 const struct ip6_tnl *t)
 294 {
 295         return __ip6gre_bucket(ign, &t->parms);
 296 }
 297
 298 static void ip6gre_tunnel_link(struct ip6gre_net *ign, struct ip6_tnl *t)
 299 {
 300         struct ip6_tnl __rcu **tp = ip6gre_bucket(ign, t);
 301
 302         rcu_assign_pointer(t->next, rtnl_dereference(*tp));
 303         rcu_assign_pointer(*tp, t);
 304 }
 305
 306 static void ip6gre_tunnel_unlink(struct ip6gre_net *ign, struct ip6_tnl *t)
 307 {
 308         struct ip6_tnl __rcu **tp;
 309         struct ip6_tnl *iter;
 310
 311         for (tp = ip6gre_bucket(ign, t);
 312              (iter = rtnl_dereference(*tp)) != NULL;
 313              tp = &iter->next) {
 314                 if (t == iter) {
 315                         rcu_assign_pointer(*tp, t->next);
 316                         break;
 317                 }
 318         }
 319 }
 320
 321 static struct ip6_tnl *ip6gre_tunnel_find(struct net *net,
 322                                            const struct __ip6_tnl_parm *parms,
 323                                            int type)
 324 {
 325         const struct in6_addr *remote = &parms->raddr;
 326         const struct in6_addr *local = &parms->laddr;
 327         __be32 key = parms->i_key;
 328         int link = parms->link;
 329         struct ip6_tnl *t;
 330         struct ip6_tnl __rcu **tp;
 331         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
 332
 333         for (tp = __ip6gre_bucket(ign, parms);
 334              (t = rtnl_dereference(*tp)) != NULL;
 335              tp = &t->next)
 336                 if (ipv6_addr_equal(local, &t->parms.laddr) &&
 337                     ipv6_addr_equal(remote, &t->parms.raddr) &&
 338                     key == t->parms.i_key &&
 339                     link == t->parms.link &&
 340                     type == t->dev->type)
 341                         break;
 342
 343         return t;
 344 }
 345
 346 static struct ip6_tnl *ip6gre_tunnel_locate(struct net *net,
 347                 const struct __ip6_tnl_parm *parms, int create)
 348 {
 349         struct ip6_tnl *t, *nt;
 350         struct net_device *dev;
 351         char name[IFNAMSIZ];
 352         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
 353
 354         t = ip6gre_tunnel_find(net, parms, ARPHRD_IP6GRE);
 355         if (t && create)
 356                 return NULL;
 357         if (t || !create)
 358                 return t;
 359
 360         if (parms->name[0]) {
 361                 if (!dev_valid_name(parms->name))
 362                         return NULL;
 363                 strlcpy(name, parms->name, IFNAMSIZ);
 364         } else {
 365                 strcpy(name, "ip6gre%d");
 366         }
 367         dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN,
 368                            ip6gre_tunnel_setup);
 369         if (!dev)
 370                 return NULL;
 371
 372         dev_net_set(dev, net);
 373
 374         nt = netdev_priv(dev);
 375         nt->parms = *parms;
 376         dev->rtnl_link_ops = &ip6gre_link_ops;
 377
 378         nt->dev = dev;
 379         nt->net = dev_net(dev);
 380
 381         if (register_netdevice(dev) < 0)
 382                 goto failed_free;
 383
 384         ip6gre_tnl_link_config(nt, 1);
 385
 386         /* Can use a lockless transmit, unless we generate output sequences */
 387         if (!(nt->parms.o_flags & TUNNEL_SEQ))
 388                 dev->features |= NETIF_F_LLTX;
 389
 390         ip6gre_tunnel_link(ign, nt);
 391         return nt;
 392
 393 failed_free:
 394         free_netdev(dev);
 395         return NULL;
 396 }
 397
 398 static void ip6erspan_tunnel_uninit(struct net_device *dev)
 399 {
 400         struct ip6_tnl *t = netdev_priv(dev);
 401         struct ip6gre_net *ign = net_generic(t->net, ip6gre_net_id);
 402
 403         ip6erspan_tunnel_unlink_md(ign, t);
 404         ip6gre_tunnel_unlink(ign, t);
 405         dst_cache_reset(&t->dst_cache);
 406         dev_put(dev);
 407 }
 408
 409 static void ip6gre_tunnel_uninit(struct net_device *dev)
 410 {
 411         struct ip6_tnl *t = netdev_priv(dev);
 412         struct ip6gre_net *ign = net_generic(t->net, ip6gre_net_id);
 413
 414         ip6gre_tunnel_unlink_md(ign, t);
 415         ip6gre_tunnel_unlink(ign, t);
 416         if (ign->fb_tunnel_dev == dev)
 417                 WRITE_ONCE(ign->fb_tunnel_dev, NULL);
 418         dst_cache_reset(&t->dst_cache);
 419         dev_put(dev);
 420 }
 421
 422
 423 static int ip6gre_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 424                        u8 type, u8 code, int offset, __be32 info)
 425 {
 426         struct net *net = dev_net(skb->dev);
 427         const struct ipv6hdr *ipv6h;
 428         struct tnl_ptk_info tpi;
 429         struct ip6_tnl *t;
 430
 431         if (gre_parse_header(skb, &tpi, NULL, htons(ETH_P_IPV6),
 432                              offset) < 0)
 433                 return -EINVAL;
 434
 435         ipv6h = (const struct ipv6hdr *)skb->data;
 436         t = ip6gre_tunnel_lookup(skb->dev, &ipv6h->daddr, &ipv6h->saddr,
 437                                  tpi.key, tpi.proto);
 438         if (!t)
 439                 return -ENOENT;
 440
 441         switch (type) {
 442         case ICMPV6_DEST_UNREACH:
 443                 net_dbg_ratelimited("%s: Path to destination invalid or inactive!\n",
 444                                     t->parms.name);
 445                 if (code != ICMPV6_PORT_UNREACH)
 446                         break;
 447                 return 0;
 448         case ICMPV6_TIME_EXCEED:
 449                 if (code == ICMPV6_EXC_HOPLIMIT) {
 450                         net_dbg_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n",
 451                                             t->parms.name);
 452                         break;
 453                 }
 454                 return 0;
 455         case ICMPV6_PARAMPROB: {
 456                 struct ipv6_tlv_tnl_enc_lim *tel;
 457                 __u32 teli;
 458
 459                 teli = 0;
 460                 if (code == ICMPV6_HDR_FIELD)
 461                         teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data);
 462
 463                 if (teli && teli == be32_to_cpu(info) - 2) {
 464                         tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli];
 465                         if (tel->encap_limit == 0) {
 466                                 net_dbg_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n",
 467                                                     t->parms.name);
 468                         }
 469                 } else {
 470                         net_dbg_ratelimited("%s: Recipient unable to parse tunneled packet!\n",
 471                                             t->parms.name);
 472                 }
 473                 return 0;
 474         }
 475         case ICMPV6_PKT_TOOBIG:
 476                 ip6_update_pmtu(skb, net, info, 0, 0, sock_net_uid(net, NULL));
 477                 return 0;
 478         case NDISC_REDIRECT:
 479                 ip6_redirect(skb, net, skb->dev->ifindex, 0,
 480                              sock_net_uid(net, NULL));
 481                 return 0;
 482         }
 483
 484         if (time_before(jiffies, t->err_time + IP6TUNNEL_ERR_TIMEO))
 485                 t->err_count++;
 486         else
 487                 t->err_count = 1;
 488         t->err_time = jiffies;
 489
 490         return 0;
 491 }
 492
 493 static int ip6gre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi)
 494 {
 495         const struct ipv6hdr *ipv6h;
 496         struct ip6_tnl *tunnel;
 497
 498         ipv6h = ipv6_hdr(skb);
 499         tunnel = ip6gre_tunnel_lookup(skb->dev,
 500                                       &ipv6h->saddr, &ipv6h->daddr, tpi->key,
 501                                       tpi->proto);
 502         if (tunnel) {
 503                 if (tunnel->parms.collect_md) {
 504                         struct metadata_dst *tun_dst;
 505                         __be64 tun_id;
 506                         __be16 flags;
 507
 508                         flags = tpi->flags;
 509                         tun_id = key32_to_tunnel_id(tpi->key);
 510
 511                         tun_dst = ipv6_tun_rx_dst(skb, flags, tun_id, 0);
 512                         if (!tun_dst)
 513                                 return PACKET_REJECT;
 514
 515                         ip6_tnl_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
 516                 } else {
 517                         ip6_tnl_rcv(tunnel, skb, tpi, NULL, log_ecn_error);
 518                 }
 519
 520                 return PACKET_RCVD;
 521         }
 522
 523         return PACKET_REJECT;
 524 }
 525
 526 static int ip6erspan_rcv(struct sk_buff *skb,
 527                          struct tnl_ptk_info *tpi,
 528                          int gre_hdr_len)
 529 {
 530         struct erspan_base_hdr *ershdr;
 531         const struct ipv6hdr *ipv6h;
 532         struct erspan_md2 *md2;
 533         struct ip6_tnl *tunnel;
 534         u8 ver;
 535
 536         ipv6h = ipv6_hdr(skb);
 537         ershdr = (struct erspan_base_hdr *)skb->data;
 538         ver = ershdr->ver;
 539
 540         tunnel = ip6gre_tunnel_lookup(skb->dev,
 541                                       &ipv6h->saddr, &ipv6h->daddr, tpi->key,
 542                                       tpi->proto);
 543         if (tunnel) {
 544                 int len = erspan_hdr_len(ver);
 545
 546                 if (unlikely(!pskb_may_pull(skb, len)))
 547                         return PACKET_REJECT;
 548
 549                 if (__iptunnel_pull_header(skb, len,
 550                                            htons(ETH_P_TEB),
 551                                            false, false) < 0)
 552                         return PACKET_REJECT;
 553
 554                 if (tunnel->parms.collect_md) {
 555                         struct erspan_metadata *pkt_md, *md;
 556                         struct metadata_dst *tun_dst;
 557                         struct ip_tunnel_info *info;
 558                         unsigned char *gh;
 559                         __be64 tun_id;
 560                         __be16 flags;
 561
 562                         tpi->flags |= TUNNEL_KEY;
 563                         flags = tpi->flags;
 564                         tun_id = key32_to_tunnel_id(tpi->key);
 565
 566                         tun_dst = ipv6_tun_rx_dst(skb, flags, tun_id,
 567                                                   sizeof(*md));
 568                         if (!tun_dst)
 569                                 return PACKET_REJECT;
 570
 571                         /* skb can be uncloned in __iptunnel_pull_header, so
 572                          * old pkt_md is no longer valid and we need to reset
 573                          * it
 574                          */
 575                         gh = skb_network_header(skb) +
 576                              skb_network_header_len(skb);
 577                         pkt_md = (struct erspan_metadata *)(gh + gre_hdr_len +
 578                                                             sizeof(*ershdr));
 579                         info = &tun_dst->u.tun_info;
 580                         md = ip_tunnel_info_opts(info);
 581                         md->version = ver;
 582                         md2 = &md->u.md2;
 583                         memcpy(md2, pkt_md, ver == 1 ? ERSPAN_V1_MDSIZE :
 584                                                        ERSPAN_V2_MDSIZE);
 585                         info->key.tun_flags |= TUNNEL_ERSPAN_OPT;
 586                         info->options_len = sizeof(*md);
 587
 588                         ip6_tnl_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
 589
 590                 } else {
 591                         ip6_tnl_rcv(tunnel, skb, tpi, NULL, log_ecn_error);
 592                 }
 593
 594                 return PACKET_RCVD;
 595         }
 596
 597         return PACKET_REJECT;
 598 }
 599
 600 static int gre_rcv(struct sk_buff *skb)
 601 {
 602         struct tnl_ptk_info tpi;
 603         bool csum_err = false;
 604         int hdr_len;
 605
 606         hdr_len = gre_parse_header(skb, &tpi, &csum_err, htons(ETH_P_IPV6), 0);
 607         if (hdr_len < 0)
 608                 goto drop;
 609
 610         if (iptunnel_pull_header(skb, hdr_len, tpi.proto, false))
 611                 goto drop;
 612
 613         if (unlikely(tpi.proto == htons(ETH_P_ERSPAN) ||
 614                      tpi.proto == htons(ETH_P_ERSPAN2))) {
 615                 if (ip6erspan_rcv(skb, &tpi, hdr_len) == PACKET_RCVD)
 616                         return 0;
 617                 goto out;
 618         }
 619
 620         if (ip6gre_rcv(skb, &tpi) == PACKET_RCVD)
 621                 return 0;
 622
 623 out:
 624         icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
 625 drop:
 626         kfree_skb(skb);
 627         return 0;
 628 }
 629
 630 static int gre_handle_offloads(struct sk_buff *skb, bool csum)
 631 {
 632         return iptunnel_handle_offloads(skb,
 633                                         csum ? SKB_GSO_GRE_CSUM : SKB_GSO_GRE);
 634 }
 635
 636 static void prepare_ip6gre_xmit_ipv4(struct sk_buff *skb,
 637                                      struct net_device *dev,
 638                                      struct flowi6 *fl6, __u8 *dsfield,
 639                                      int *encap_limit)
 640 {
 641         const struct iphdr *iph = ip_hdr(skb);
 642         struct ip6_tnl *t = netdev_priv(dev);
 643
 644         if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
 645                 *encap_limit = t->parms.encap_limit;
 646
 647         memcpy(fl6, &t->fl.u.ip6, sizeof(*fl6));
 648
 649         if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
 650                 *dsfield = ipv4_get_dsfield(iph);
 651         else
 652                 *dsfield = ip6_tclass(t->parms.flowinfo);
 653
 654         if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
 655                 fl6->flowi6_mark = skb->mark;
 656         else
 657                 fl6->flowi6_mark = t->parms.fwmark;
 658
 659         fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
 660 }
 661
 662 static int prepare_ip6gre_xmit_ipv6(struct sk_buff *skb,
 663                                     struct net_device *dev,
 664                                     struct flowi6 *fl6, __u8 *dsfield,
 665                                     int *encap_limit)
 666 {
 667         struct ipv6hdr *ipv6h;
 668         struct ip6_tnl *t = netdev_priv(dev);
 669         __u16 offset;
 670
 671         offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb));
 672         /* ip6_tnl_parse_tlv_enc_lim() might have reallocated skb->head */
 673         ipv6h = ipv6_hdr(skb);
 674
 675         if (offset > 0) {
 676                 struct ipv6_tlv_tnl_enc_lim *tel;
 677
 678                 tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset];
 679                 if (tel->encap_limit == 0) {
 680                         icmpv6_ndo_send(skb, ICMPV6_PARAMPROB,
 681                                         ICMPV6_HDR_FIELD, offset + 2);
 682                         return -1;
 683                 }
 684                 *encap_limit = tel->encap_limit - 1;
 685         } else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) {
 686                 *encap_limit = t->parms.encap_limit;
 687         }
 688
 689         memcpy(fl6, &t->fl.u.ip6, sizeof(*fl6));
 690
 691         if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
 692                 *dsfield = ipv6_get_dsfield(ipv6h);
 693         else
 694                 *dsfield = ip6_tclass(t->parms.flowinfo);
 695
 696         if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL)
 697                 fl6->flowlabel |= ip6_flowlabel(ipv6h);
 698
 699         if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
 700                 fl6->flowi6_mark = skb->mark;
 701         else
 702                 fl6->flowi6_mark = t->parms.fwmark;
 703
 704         fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
 705
 706         return 0;
 707 }
 708
 709 static struct ip_tunnel_info *skb_tunnel_info_txcheck(struct sk_buff *skb)
 710 {
 711         struct ip_tunnel_info *tun_info;
 712
 713         tun_info = skb_tunnel_info(skb);
 714         if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX)))
 715                 return ERR_PTR(-EINVAL);
 716
 717         return tun_info;
 718 }
 719
 720 static netdev_tx_t __gre6_xmit(struct sk_buff *skb,
 721                                struct net_device *dev, __u8 dsfield,
 722                                struct flowi6 *fl6, int encap_limit,
 723                                __u32 *pmtu, __be16 proto)
 724 {
 725         struct ip6_tnl *tunnel = netdev_priv(dev);
 726         __be16 protocol;
 727         __be16 flags;
 728
 729         if (dev->type == ARPHRD_ETHER)
 730                 IPCB(skb)->flags = 0;
 731
 732         if (dev->header_ops && dev->type == ARPHRD_IP6GRE)
 733                 fl6->daddr = ((struct ipv6hdr *)skb->data)->daddr;
 734         else
 735                 fl6->daddr = tunnel->parms.raddr;
 736
 737         /* Push GRE header. */
 738         protocol = (dev->type == ARPHRD_ETHER) ? htons(ETH_P_TEB) : proto;
 739
 740         if (tunnel->parms.collect_md) {
 741                 struct ip_tunnel_info *tun_info;
 742                 const struct ip_tunnel_key *key;
 743                 int tun_hlen;
 744
 745                 tun_info = skb_tunnel_info_txcheck(skb);
 746                 if (IS_ERR(tun_info) ||
 747                     unlikely(ip_tunnel_info_af(tun_info) != AF_INET6))
 748                         return -EINVAL;
 749
 750                 key = &tun_info->key;
 751                 memset(fl6, 0, sizeof(*fl6));
 752                 fl6->flowi6_proto = IPPROTO_GRE;
 753                 fl6->daddr = key->u.ipv6.dst;
 754                 fl6->flowlabel = key->label;
 755                 fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
 756                 fl6->fl6_gre_key = tunnel_id_to_key32(key->tun_id);
 757
 758                 dsfield = key->tos;
 759                 flags = key->tun_flags &
 760                         (TUNNEL_CSUM | TUNNEL_KEY | TUNNEL_SEQ);
 761                 tun_hlen = gre_calc_hlen(flags);
 762
 763                 if (skb_cow_head(skb, dev->needed_headroom ?: tun_hlen + tunnel->encap_hlen))
 764                         return -ENOMEM;
 765
 766                 gre_build_header(skb, tun_hlen,
 767                                  flags, protocol,
 768                                  tunnel_id_to_key32(tun_info->key.tun_id),
 769                                  (flags & TUNNEL_SEQ) ? htonl(atomic_fetch_inc(&tunnel->o_seqno))
 770                                                       : 0);
 771
 772         } else {
 773                 if (skb_cow_head(skb, dev->needed_headroom ?: tunnel->hlen))
 774                         return -ENOMEM;
 775
 776                 flags = tunnel->parms.o_flags;
 777
 778                 gre_build_header(skb, tunnel->tun_hlen, flags,
 779                                  protocol, tunnel->parms.o_key,
 780                                  (flags & TUNNEL_SEQ) ? htonl(atomic_fetch_inc(&tunnel->o_seqno))
 781                                                       : 0);
 782         }
 783
 784         return ip6_tnl_xmit(skb, dev, dsfield, fl6, encap_limit, pmtu,
 785                             NEXTHDR_GRE);
 786 }
 787
 788 static inline int ip6gre_xmit_ipv4(struct sk_buff *skb, struct net_device *dev)
 789 {
 790         struct ip6_tnl *t = netdev_priv(dev);
 791         int encap_limit = -1;
 792         struct flowi6 fl6;
 793         __u8 dsfield = 0;
 794         __u32 mtu;
 795         int err;
 796
 797         memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
 798
 799         if (!t->parms.collect_md)
 800                 prepare_ip6gre_xmit_ipv4(skb, dev, &fl6,
 801                                          &dsfield, &encap_limit);
 802
 803         err = gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM));
 804         if (err)
 805                 return -1;
 806
 807         err = __gre6_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu,
 808                           skb->protocol);
 809         if (err != 0) {
 810                 /* XXX: send ICMP error even if DF is not set. */
 811                 if (err == -EMSGSIZE)
 812                         icmp_ndo_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
 813                                       htonl(mtu));
 814                 return -1;
 815         }
 816
 817         return 0;
 818 }
 819
 820 static inline int ip6gre_xmit_ipv6(struct sk_buff *skb, struct net_device *dev)
 821 {
 822         struct ip6_tnl *t = netdev_priv(dev);
 823         struct ipv6hdr *ipv6h = ipv6_hdr(skb);
 824         int encap_limit = -1;
 825         struct flowi6 fl6;
 826         __u8 dsfield = 0;
 827         __u32 mtu;
 828         int err;
 829
 830         if (ipv6_addr_equal(&t->parms.raddr, &ipv6h->saddr))
 831                 return -1;
 832
 833         if (!t->parms.collect_md &&
 834             prepare_ip6gre_xmit_ipv6(skb, dev, &fl6, &dsfield, &encap_limit))
 835                 return -1;
 836
 837         if (gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM)))
 838                 return -1;
 839
 840         err = __gre6_xmit(skb, dev, dsfield, &fl6, encap_limit,
 841                           &mtu, skb->protocol);
 842         if (err != 0) {
 843                 if (err == -EMSGSIZE)
 844                         icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
 845                 return -1;
 846         }
 847
 848         return 0;
 849 }
 850
 851 /**
 852  * ip6gre_tnl_addr_conflict - compare packet addresses to tunnel's own
 853  *   @t: the outgoing tunnel device
 854  *   @hdr: IPv6 header from the incoming packet
 855  *
 856  * Description:
 857  *   Avoid trivial tunneling loop by checking that tunnel exit-point
 858  *   doesn't match source of incoming packet.
 859  *
 860  * Return:
 861  *   1 if conflict,
 862  *   0 else
 863  **/
 864
 865 static inline bool ip6gre_tnl_addr_conflict(const struct ip6_tnl *t,
 866         const struct ipv6hdr *hdr)
 867 {
 868         return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr);
 869 }
 870
 871 static int ip6gre_xmit_other(struct sk_buff *skb, struct net_device *dev)
 872 {
 873         struct ip6_tnl *t = netdev_priv(dev);
 874         int encap_limit = -1;
 875         struct flowi6 fl6;
 876         __u32 mtu;
 877         int err;
 878
 879         if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
 880                 encap_limit = t->parms.encap_limit;
 881
 882         if (!t->parms.collect_md)
 883                 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
 884
 885         err = gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM));
 886         if (err)
 887                 return err;
 888
 889         err = __gre6_xmit(skb, dev, 0, &fl6, encap_limit, &mtu, skb->protocol);
 890
 891         return err;
 892 }
 893
 894 static netdev_tx_t ip6gre_tunnel_xmit(struct sk_buff *skb,
 895         struct net_device *dev)
 896 {
 897         struct ip6_tnl *t = netdev_priv(dev);
 898         struct net_device_stats *stats = &t->dev->stats;
 899         int ret;
 900
 901         if (!pskb_inet_may_pull(skb))
 902                 goto tx_err;
 903
 904         if (!ip6_tnl_xmit_ctl(t, &t->parms.laddr, &t->parms.raddr))
 905                 goto tx_err;
 906
 907         switch (skb->protocol) {
 908         case htons(ETH_P_IP):
 909                 ret = ip6gre_xmit_ipv4(skb, dev);
 910                 break;
 911         case htons(ETH_P_IPV6):
 912                 ret = ip6gre_xmit_ipv6(skb, dev);
 913                 break;
 914         default:
 915                 ret = ip6gre_xmit_other(skb, dev);
 916                 break;
 917         }
 918
 919         if (ret < 0)
 920                 goto tx_err;
 921
 922         return NETDEV_TX_OK;
 923
 924 tx_err:
 925         if (!t->parms.collect_md || !IS_ERR(skb_tunnel_info_txcheck(skb)))
 926                 stats->tx_errors++;
 927         stats->tx_dropped++;
 928         kfree_skb(skb);
 929         return NETDEV_TX_OK;
 930 }
 931
 932 static netdev_tx_t ip6erspan_tunnel_xmit(struct sk_buff *skb,
 933                                          struct net_device *dev)
 934 {
 935         struct ip_tunnel_info *tun_info = NULL;
 936         struct ip6_tnl *t = netdev_priv(dev);
 937         struct dst_entry *dst = skb_dst(skb);
 938         struct net_device_stats *stats;
 939         bool truncate = false;
 940         int encap_limit = -1;
 941         __u8 dsfield = false;
 942         struct flowi6 fl6;
 943         int err = -EINVAL;
 944         __be16 proto;
 945         __u32 mtu;
 946         int nhoff;
 947
 948         if (!pskb_inet_may_pull(skb))
 949                 goto tx_err;
 950
 951         if (!ip6_tnl_xmit_ctl(t, &t->parms.laddr, &t->parms.raddr))
 952                 goto tx_err;
 953
 954         if (gre_handle_offloads(skb, false))
 955                 goto tx_err;
 956
 957         if (skb->len > dev->mtu + dev->hard_header_len) {
 958                 pskb_trim(skb, dev->mtu + dev->hard_header_len);
 959                 truncate = true;
 960         }
 961
 962         nhoff = skb_network_header(skb) - skb_mac_header(skb);
 963         if (skb->protocol == htons(ETH_P_IP) &&
 964             (ntohs(ip_hdr(skb)->tot_len) > skb->len - nhoff))
 965                 truncate = true;
 966
 967         if (skb->protocol == htons(ETH_P_IPV6)) {
 968                 int thoff;
 969
 970                 if (skb_transport_header_was_set(skb))
 971                         thoff = skb_transport_header(skb) - skb_mac_header(skb);
 972                 else
 973                         thoff = nhoff + sizeof(struct ipv6hdr);
 974                 if (ntohs(ipv6_hdr(skb)->payload_len) > skb->len - thoff)
 975                         truncate = true;
 976         }
 977
 978         if (skb_cow_head(skb, dev->needed_headroom ?: t->hlen))
 979                 goto tx_err;
 980
 981         t->parms.o_flags &= ~TUNNEL_KEY;
 982         IPCB(skb)->flags = 0;
 983
 984         /* For collect_md mode, derive fl6 from the tunnel key,
 985          * for native mode, call prepare_ip6gre_xmit_{ipv4,ipv6}.
 986          */
 987         if (t->parms.collect_md) {
 988                 const struct ip_tunnel_key *key;
 989                 struct erspan_metadata *md;
 990                 __be32 tun_id;
 991
 992                 tun_info = skb_tunnel_info_txcheck(skb);
 993                 if (IS_ERR(tun_info) ||
 994                     unlikely(ip_tunnel_info_af(tun_info) != AF_INET6))
 995                         goto tx_err;
 996
 997                 key = &tun_info->key;
 998                 memset(&fl6, 0, sizeof(fl6));
 999                 fl6.flowi6_proto = IPPROTO_GRE;
1000                 fl6.daddr = key->u.ipv6.dst;
1001                 fl6.flowlabel = key->label;
1002                 fl6.flowi6_uid = sock_net_uid(dev_net(dev), NULL);
1003                 fl6.fl6_gre_key = tunnel_id_to_key32(key->tun_id);
1004
1005                 dsfield = key->tos;
1006                 if (!(tun_info->key.tun_flags & TUNNEL_ERSPAN_OPT))
1007                         goto tx_err;
1008                 if (tun_info->options_len < sizeof(*md))
1009                         goto tx_err;
1010                 md = ip_tunnel_info_opts(tun_info);
1011
1012                 tun_id = tunnel_id_to_key32(key->tun_id);
1013                 if (md->version == 1) {
1014                         erspan_build_header(skb,
1015                                             ntohl(tun_id),
1016                                             ntohl(md->u.index), truncate,
1017                                             false);
1018                 } else if (md->version == 2) {
1019                         erspan_build_header_v2(skb,
1020                                                ntohl(tun_id),
1021                                                md->u.md2.dir,
1022                                                get_hwid(&md->u.md2),
1023                                                truncate, false);
1024                 } else {
1025                         goto tx_err;
1026                 }
1027         } else {
1028                 switch (skb->protocol) {
1029                 case htons(ETH_P_IP):
1030                         memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
1031                         prepare_ip6gre_xmit_ipv4(skb, dev, &fl6,
1032                                                  &dsfield, &encap_limit);
1033                         break;
1034                 case htons(ETH_P_IPV6):
1035                         if (ipv6_addr_equal(&t->parms.raddr, &ipv6_hdr(skb)->saddr))
1036                                 goto tx_err;
1037                         if (prepare_ip6gre_xmit_ipv6(skb, dev, &fl6,
1038                                                      &dsfield, &encap_limit))
1039                                 goto tx_err;
1040                         break;
1041                 default:
1042                         memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
1043                         break;
1044                 }
1045
1046                 if (t->parms.erspan_ver == 1)
1047                         erspan_build_header(skb, ntohl(t->parms.o_key),
1048                                             t->parms.index,
1049                                             truncate, false);
1050                 else if (t->parms.erspan_ver == 2)
1051                         erspan_build_header_v2(skb, ntohl(t->parms.o_key),
1052                                                t->parms.dir,
1053                                                t->parms.hwid,
1054                                                truncate, false);
1055                 else
1056                         goto tx_err;
1057
1058                 fl6.daddr = t->parms.raddr;
1059         }
1060
1061         /* Push GRE header. */
1062         proto = (t->parms.erspan_ver == 1) ? htons(ETH_P_ERSPAN)
1063                                            : htons(ETH_P_ERSPAN2);
1064         gre_build_header(skb, 8, TUNNEL_SEQ, proto, 0, htonl(atomic_fetch_inc(&t->o_seqno)));
1065
1066         /* TooBig packet may have updated dst->dev's mtu */
1067         if (!t->parms.collect_md && dst && dst_mtu(dst) > dst->dev->mtu)
1068                 dst->ops->update_pmtu(dst, NULL, skb, dst->dev->mtu, false);
1069
1070         err = ip6_tnl_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu,
1071                            NEXTHDR_GRE);
1072         if (err != 0) {
1073                 /* XXX: send ICMP error even if DF is not set. */
1074                 if (err == -EMSGSIZE) {
1075                         if (skb->protocol == htons(ETH_P_IP))
1076                                 icmp_ndo_send(skb, ICMP_DEST_UNREACH,
1077                                               ICMP_FRAG_NEEDED, htonl(mtu));
1078                         else
1079                                 icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
1080                 }
1081
1082                 goto tx_err;
1083         }
1084         return NETDEV_TX_OK;
1085
1086 tx_err:
1087         stats = &t->dev->stats;
1088         if (!IS_ERR(tun_info))
1089                 stats->tx_errors++;
1090         stats->tx_dropped++;
1091         kfree_skb(skb);
1092         return NETDEV_TX_OK;
1093 }
1094
1095 static void ip6gre_tnl_link_config_common(struct ip6_tnl *t)
1096 {
1097         struct net_device *dev = t->dev;
1098         struct __ip6_tnl_parm *p = &t->parms;
1099         struct flowi6 *fl6 = &t->fl.u.ip6;
1100
1101         if (dev->type != ARPHRD_ETHER) {
1102                 memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr));
1103                 memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr));
1104         }
1105
1106         /* Set up flowi template */
1107         fl6->saddr = p->laddr;
1108         fl6->daddr = p->raddr;
1109         fl6->flowi6_oif = p->link;
1110         fl6->flowlabel = 0;
1111         fl6->flowi6_proto = IPPROTO_GRE;
1112         fl6->fl6_gre_key = t->parms.o_key;
1113
1114         if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS))
1115                 fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo;
1116         if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL))
1117                 fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo;
1118
1119         p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET);
1120         p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr);
1121
1122         if (p->flags&IP6_TNL_F_CAP_XMIT &&
1123                         p->flags&IP6_TNL_F_CAP_RCV && dev->type != ARPHRD_ETHER)
1124                 dev->flags |= IFF_POINTOPOINT;
1125         else
1126                 dev->flags &= ~IFF_POINTOPOINT;
1127 }
1128
1129 static void ip6gre_tnl_link_config_route(struct ip6_tnl *t, int set_mtu,
1130                                          int t_hlen)
1131 {
1132         const struct __ip6_tnl_parm *p = &t->parms;
1133         struct net_device *dev = t->dev;
1134
1135         if (p->flags & IP6_TNL_F_CAP_XMIT) {
1136                 int strict = (ipv6_addr_type(&p->raddr) &
1137                               (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL));
1138
1139                 struct rt6_info *rt = rt6_lookup(t->net,
1140                                                  &p->raddr, &p->laddr,
1141                                                  p->link, NULL, strict);
1142
1143                 if (!rt)
1144                         return;
1145
1146                 if (rt->dst.dev) {
1147                         unsigned short dst_len = rt->dst.dev->hard_header_len +
1148                                                  t_hlen;
1149
1150                         if (t->dev->header_ops)
1151                                 dev->hard_header_len = dst_len;
1152                         else
1153                                 dev->needed_headroom = dst_len;
1154
1155                         if (set_mtu) {
1156                                 int mtu = rt->dst.dev->mtu - t_hlen;
1157
1158                                 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1159                                         mtu -= 8;
1160                                 if (dev->type == ARPHRD_ETHER)
1161                                         mtu -= ETH_HLEN;
1162
1163                                 if (mtu < IPV6_MIN_MTU)
1164                                         mtu = IPV6_MIN_MTU;
1165                                 WRITE_ONCE(dev->mtu, mtu);
1166                         }
1167                 }
1168                 ip6_rt_put(rt);
1169         }
1170 }
1171
1172 static int ip6gre_calc_hlen(struct ip6_tnl *tunnel)
1173 {
1174         int t_hlen;
1175
1176         tunnel->tun_hlen = gre_calc_hlen(tunnel->parms.o_flags);
1177         tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen;
1178
1179         t_hlen = tunnel->hlen + sizeof(struct ipv6hdr);
1180
1181         if (tunnel->dev->header_ops)
1182                 tunnel->dev->hard_header_len = LL_MAX_HEADER + t_hlen;
1183         else
1184                 tunnel->dev->needed_headroom = LL_MAX_HEADER + t_hlen;
1185
1186         return t_hlen;
1187 }
1188
1189 static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu)
1190 {
1191         ip6gre_tnl_link_config_common(t);
1192         ip6gre_tnl_link_config_route(t, set_mtu, ip6gre_calc_hlen(t));
1193 }
1194
1195 static void ip6gre_tnl_copy_tnl_parm(struct ip6_tnl *t,
1196                                      const struct __ip6_tnl_parm *p)
1197 {
1198         t->parms.laddr = p->laddr;
1199         t->parms.raddr = p->raddr;
1200         t->parms.flags = p->flags;
1201         t->parms.hop_limit = p->hop_limit;
1202         t->parms.encap_limit = p->encap_limit;
1203         t->parms.flowinfo = p->flowinfo;
1204         t->parms.link = p->link;
1205         t->parms.proto = p->proto;
1206         t->parms.i_key = p->i_key;
1207         t->parms.o_key = p->o_key;
1208         t->parms.i_flags = p->i_flags;
1209         t->parms.o_flags = p->o_flags;
1210         t->parms.fwmark = p->fwmark;
1211         t->parms.erspan_ver = p->erspan_ver;
1212         t->parms.index = p->index;
1213         t->parms.dir = p->dir;
1214         t->parms.hwid = p->hwid;
1215         dst_cache_reset(&t->dst_cache);
1216 }
1217
1218 static int ip6gre_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p,
1219                              int set_mtu)
1220 {
1221         ip6gre_tnl_copy_tnl_parm(t, p);
1222         ip6gre_tnl_link_config(t, set_mtu);
1223         return 0;
1224 }
1225
1226 static void ip6gre_tnl_parm_from_user(struct __ip6_tnl_parm *p,
1227         const struct ip6_tnl_parm2 *u)
1228 {
1229         p->laddr = u->laddr;
1230         p->raddr = u->raddr;
1231         p->flags = u->flags;
1232         p->hop_limit = u->hop_limit;
1233         p->encap_limit = u->encap_limit;
1234         p->flowinfo = u->flowinfo;
1235         p->link = u->link;
1236         p->i_key = u->i_key;
1237         p->o_key = u->o_key;
1238         p->i_flags = gre_flags_to_tnl_flags(u->i_flags);
1239         p->o_flags = gre_flags_to_tnl_flags(u->o_flags);
1240         memcpy(p->name, u->name, sizeof(u->name));
1241 }
1242
1243 static void ip6gre_tnl_parm_to_user(struct ip6_tnl_parm2 *u,
1244         const struct __ip6_tnl_parm *p)
1245 {
1246         u->proto = IPPROTO_GRE;
1247         u->laddr = p->laddr;
1248         u->raddr = p->raddr;
1249         u->flags = p->flags;
1250         u->hop_limit = p->hop_limit;
1251         u->encap_limit = p->encap_limit;
1252         u->flowinfo = p->flowinfo;
1253         u->link = p->link;
1254         u->i_key = p->i_key;
1255         u->o_key = p->o_key;
1256         u->i_flags = gre_tnl_flags_to_gre_flags(p->i_flags);
1257         u->o_flags = gre_tnl_flags_to_gre_flags(p->o_flags);
1258         memcpy(u->name, p->name, sizeof(u->name));
1259 }
1260
1261 static int ip6gre_tunnel_siocdevprivate(struct net_device *dev,
1262                                         struct ifreq *ifr, void __user *data,
1263                                         int cmd)
1264 {
1265         int err = 0;
1266         struct ip6_tnl_parm2 p;
1267         struct __ip6_tnl_parm p1;
1268         struct ip6_tnl *t = netdev_priv(dev);
1269         struct net *net = t->net;
1270         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1271
1272         memset(&p1, 0, sizeof(p1));
1273
1274         switch (cmd) {
1275         case SIOCGETTUNNEL:
1276                 if (dev == ign->fb_tunnel_dev) {
1277                         if (copy_from_user(&p, data, sizeof(p))) {
1278                                 err = -EFAULT;
1279                                 break;
1280                         }
1281                         ip6gre_tnl_parm_from_user(&p1, &p);
1282                         t = ip6gre_tunnel_locate(net, &p1, 0);
1283                         if (!t)
1284                                 t = netdev_priv(dev);
1285                 }
1286                 memset(&p, 0, sizeof(p));
1287                 ip6gre_tnl_parm_to_user(&p, &t->parms);
1288                 if (copy_to_user(data, &p, sizeof(p)))
1289                         err = -EFAULT;
1290                 break;
1291
1292         case SIOCADDTUNNEL:
1293         case SIOCCHGTUNNEL:
1294                 err = -EPERM;
1295                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1296                         goto done;
1297
1298                 err = -EFAULT;
1299                 if (copy_from_user(&p, data, sizeof(p)))
1300                         goto done;
1301
1302                 err = -EINVAL;
1303                 if ((p.i_flags|p.o_flags)&(GRE_VERSION|GRE_ROUTING))
1304                         goto done;
1305
1306                 if (!(p.i_flags&GRE_KEY))
1307                         p.i_key = 0;
1308                 if (!(p.o_flags&GRE_KEY))
1309                         p.o_key = 0;
1310
1311                 ip6gre_tnl_parm_from_user(&p1, &p);
1312                 t = ip6gre_tunnel_locate(net, &p1, cmd == SIOCADDTUNNEL);
1313
1314                 if (dev != ign->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
1315                         if (t) {
1316                                 if (t->dev != dev) {
1317                                         err = -EEXIST;
1318                                         break;
1319                                 }
1320                         } else {
1321                                 t = netdev_priv(dev);
1322
1323                                 ip6gre_tunnel_unlink(ign, t);
1324                                 synchronize_net();
1325                                 ip6gre_tnl_change(t, &p1, 1);
1326                                 ip6gre_tunnel_link(ign, t);
1327                                 netdev_state_change(dev);
1328                         }
1329                 }
1330
1331                 if (t) {
1332                         err = 0;
1333
1334                         memset(&p, 0, sizeof(p));
1335                         ip6gre_tnl_parm_to_user(&p, &t->parms);
1336                         if (copy_to_user(data, &p, sizeof(p)))
1337                                 err = -EFAULT;
1338                 } else
1339                         err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
1340                 break;
1341
1342         case SIOCDELTUNNEL:
1343                 err = -EPERM;
1344                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1345                         goto done;
1346
1347                 if (dev == ign->fb_tunnel_dev) {
1348                         err = -EFAULT;
1349                         if (copy_from_user(&p, data, sizeof(p)))
1350                                 goto done;
1351                         err = -ENOENT;
1352                         ip6gre_tnl_parm_from_user(&p1, &p);
1353                         t = ip6gre_tunnel_locate(net, &p1, 0);
1354                         if (!t)
1355                                 goto done;
1356                         err = -EPERM;
1357                         if (t == netdev_priv(ign->fb_tunnel_dev))
1358                                 goto done;
1359                         dev = t->dev;
1360                 }
1361                 unregister_netdevice(dev);
1362                 err = 0;
1363                 break;
1364
1365         default:
1366                 err = -EINVAL;
1367         }
1368
1369 done:
1370         return err;
1371 }
1372
1373 static int ip6gre_header(struct sk_buff *skb, struct net_device *dev,
1374                          unsigned short type, const void *daddr,
1375                          const void *saddr, unsigned int len)
1376 {
1377         struct ip6_tnl *t = netdev_priv(dev);
1378         struct ipv6hdr *ipv6h;
1379         __be16 *p;
1380
1381         ipv6h = skb_push(skb, t->hlen + sizeof(*ipv6h));
1382         ip6_flow_hdr(ipv6h, 0, ip6_make_flowlabel(dev_net(dev), skb,
1383                                                   t->fl.u.ip6.flowlabel,
1384                                                   true, &t->fl.u.ip6));
1385         ipv6h->hop_limit = t->parms.hop_limit;
1386         ipv6h->nexthdr = NEXTHDR_GRE;
1387         ipv6h->saddr = t->parms.laddr;
1388         ipv6h->daddr = t->parms.raddr;
1389
1390         p = (__be16 *)(ipv6h + 1);
1391         p[0] = t->parms.o_flags;
1392         p[1] = htons(type);
1393
1394         /*
1395          *      Set the source hardware address.
1396          */
1397
1398         if (saddr)
1399                 memcpy(&ipv6h->saddr, saddr, sizeof(struct in6_addr));
1400         if (daddr)
1401                 memcpy(&ipv6h->daddr, daddr, sizeof(struct in6_addr));
1402         if (!ipv6_addr_any(&ipv6h->daddr))
1403                 return t->hlen;
1404
1405         return -t->hlen;
1406 }
1407
1408 static const struct header_ops ip6gre_header_ops = {
1409         .create = ip6gre_header,
1410 };
1411
1412 static const struct net_device_ops ip6gre_netdev_ops = {
1413         .ndo_init               = ip6gre_tunnel_init,
1414         .ndo_uninit             = ip6gre_tunnel_uninit,
1415         .ndo_start_xmit         = ip6gre_tunnel_xmit,
1416         .ndo_siocdevprivate     = ip6gre_tunnel_siocdevprivate,
1417         .ndo_change_mtu         = ip6_tnl_change_mtu,
1418         .ndo_get_stats64        = dev_get_tstats64,
1419         .ndo_get_iflink         = ip6_tnl_get_iflink,
1420 };
1421
1422 static void ip6gre_dev_free(struct net_device *dev)
1423 {
1424         struct ip6_tnl *t = netdev_priv(dev);
1425
1426         gro_cells_destroy(&t->gro_cells);
1427         dst_cache_destroy(&t->dst_cache);
1428         free_percpu(dev->tstats);
1429 }
1430
1431 static void ip6gre_tunnel_setup(struct net_device *dev)
1432 {
1433         dev->netdev_ops = &ip6gre_netdev_ops;
1434         dev->needs_free_netdev = true;
1435         dev->priv_destructor = ip6gre_dev_free;
1436
1437         dev->type = ARPHRD_IP6GRE;
1438
1439         dev->flags |= IFF_NOARP;
1440         dev->addr_len = sizeof(struct in6_addr);
1441         netif_keep_dst(dev);
1442         /* This perm addr will be used as interface identifier by IPv6 */
1443         dev->addr_assign_type = NET_ADDR_RANDOM;
1444         eth_random_addr(dev->perm_addr);
1445 }
1446
1447 #define GRE6_FEATURES (NETIF_F_SG |             \
1448                        NETIF_F_FRAGLIST |       \
1449                        NETIF_F_HIGHDMA |        \
1450                        NETIF_F_HW_CSUM)
1451
1452 static void ip6gre_tnl_init_features(struct net_device *dev)
1453 {
1454         struct ip6_tnl *nt = netdev_priv(dev);
1455
1456         dev->features           |= GRE6_FEATURES;
1457         dev->hw_features        |= GRE6_FEATURES;
1458
1459         if (!(nt->parms.o_flags & TUNNEL_SEQ)) {
1460                 /* TCP offload with GRE SEQ is not supported, nor
1461                  * can we support 2 levels of outer headers requiring
1462                  * an update.
1463                  */
1464                 if (!(nt->parms.o_flags & TUNNEL_CSUM) ||
1465                     nt->encap.type == TUNNEL_ENCAP_NONE) {
1466                         dev->features    |= NETIF_F_GSO_SOFTWARE;
1467                         dev->hw_features |= NETIF_F_GSO_SOFTWARE;
1468                 }
1469
1470                 /* Can use a lockless transmit, unless we generate
1471                  * output sequences
1472                  */
1473                 dev->features |= NETIF_F_LLTX;
1474         }
1475 }
1476
1477 static int ip6gre_tunnel_init_common(struct net_device *dev)
1478 {
1479         struct ip6_tnl *tunnel;
1480         int ret;
1481         int t_hlen;
1482
1483         tunnel = netdev_priv(dev);
1484
1485         tunnel->dev = dev;
1486         tunnel->net = dev_net(dev);
1487         strcpy(tunnel->parms.name, dev->name);
1488
1489         dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1490         if (!dev->tstats)
1491                 return -ENOMEM;
1492
1493         ret = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
1494         if (ret)
1495                 goto cleanup_alloc_pcpu_stats;
1496
1497         ret = gro_cells_init(&tunnel->gro_cells, dev);
1498         if (ret)
1499                 goto cleanup_dst_cache_init;
1500
1501         t_hlen = ip6gre_calc_hlen(tunnel);
1502         dev->mtu = ETH_DATA_LEN - t_hlen;
1503         if (dev->type == ARPHRD_ETHER)
1504                 dev->mtu -= ETH_HLEN;
1505         if (!(tunnel->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1506                 dev->mtu -= 8;
1507
1508         if (tunnel->parms.collect_md) {
1509                 netif_keep_dst(dev);
1510         }
1511         ip6gre_tnl_init_features(dev);
1512
1513         dev_hold(dev);
1514         return 0;
1515
1516 cleanup_dst_cache_init:
1517         dst_cache_destroy(&tunnel->dst_cache);
1518 cleanup_alloc_pcpu_stats:
1519         free_percpu(dev->tstats);
1520         dev->tstats = NULL;
1521         return ret;
1522 }
1523
1524 static int ip6gre_tunnel_init(struct net_device *dev)
1525 {
1526         struct ip6_tnl *tunnel;
1527         int ret;
1528
1529         ret = ip6gre_tunnel_init_common(dev);
1530         if (ret)
1531                 return ret;
1532
1533         tunnel = netdev_priv(dev);
1534
1535         if (tunnel->parms.collect_md)
1536                 return 0;
1537
1538         memcpy(dev->dev_addr, &tunnel->parms.laddr, sizeof(struct in6_addr));
1539         memcpy(dev->broadcast, &tunnel->parms.raddr, sizeof(struct in6_addr));
1540
1541         if (ipv6_addr_any(&tunnel->parms.raddr))
1542                 dev->header_ops = &ip6gre_header_ops;
1543
1544         return 0;
1545 }
1546
1547 static void ip6gre_fb_tunnel_init(struct net_device *dev)
1548 {
1549         struct ip6_tnl *tunnel = netdev_priv(dev);
1550
1551         tunnel->dev = dev;
1552         tunnel->net = dev_net(dev);
1553         strcpy(tunnel->parms.name, dev->name);
1554
1555         tunnel->hlen            = sizeof(struct ipv6hdr) + 4;
1556 }
1557
1558 static struct inet6_protocol ip6gre_protocol __read_mostly = {
1559         .handler     = gre_rcv,
1560         .err_handler = ip6gre_err,
1561         .flags       = INET6_PROTO_FINAL,
1562 };
1563
1564 static void ip6gre_destroy_tunnels(struct net *net, struct list_head *head)
1565 {
1566         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1567         struct net_device *dev, *aux;
1568         int prio;
1569
1570         for_each_netdev_safe(net, dev, aux)
1571                 if (dev->rtnl_link_ops == &ip6gre_link_ops ||
1572                     dev->rtnl_link_ops == &ip6gre_tap_ops ||
1573                     dev->rtnl_link_ops == &ip6erspan_tap_ops)
1574                         unregister_netdevice_queue(dev, head);
1575
1576         for (prio = 0; prio < 4; prio++) {
1577                 int h;
1578                 for (h = 0; h < IP6_GRE_HASH_SIZE; h++) {
1579                         struct ip6_tnl *t;
1580
1581                         t = rtnl_dereference(ign->tunnels[prio][h]);
1582
1583                         while (t) {
1584                                 /* If dev is in the same netns, it has already
1585                                  * been added to the list by the previous loop.
1586                                  */
1587                                 if (!net_eq(dev_net(t->dev), net))
1588                                         unregister_netdevice_queue(t->dev,
1589                                                                    head);
1590                                 t = rtnl_dereference(t->next);
1591                         }
1592                 }
1593         }
1594 }
1595
1596 static int __net_init ip6gre_init_net(struct net *net)
1597 {
1598         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1599         struct net_device *ndev;
1600         int err;
1601
1602         if (!net_has_fallback_tunnels(net))
1603                 return 0;
1604         ndev = alloc_netdev(sizeof(struct ip6_tnl), "ip6gre0",
1605                             NET_NAME_UNKNOWN, ip6gre_tunnel_setup);
1606         if (!ndev) {
1607                 err = -ENOMEM;
1608                 goto err_alloc_dev;
1609         }
1610         ign->fb_tunnel_dev = ndev;
1611         dev_net_set(ign->fb_tunnel_dev, net);
1612         /* FB netdevice is special: we have one, and only one per netns.
1613          * Allowing to move it to another netns is clearly unsafe.
1614          */
1615         ign->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL;
1616
1617
1618         ip6gre_fb_tunnel_init(ign->fb_tunnel_dev);
1619         ign->fb_tunnel_dev->rtnl_link_ops = &ip6gre_link_ops;
1620
1621         err = register_netdev(ign->fb_tunnel_dev);
1622         if (err)
1623                 goto err_reg_dev;
1624
1625         rcu_assign_pointer(ign->tunnels_wc[0],
1626                            netdev_priv(ign->fb_tunnel_dev));
1627         return 0;
1628
1629 err_reg_dev:
1630         free_netdev(ndev);
1631 err_alloc_dev:
1632         return err;
1633 }
1634
1635 static void __net_exit ip6gre_exit_batch_net(struct list_head *net_list)
1636 {
1637         struct net *net;
1638         LIST_HEAD(list);
1639
1640         rtnl_lock();
1641         list_for_each_entry(net, net_list, exit_list)
1642                 ip6gre_destroy_tunnels(net, &list);
1643         unregister_netdevice_many(&list);
1644         rtnl_unlock();
1645 }
1646
1647 static struct pernet_operations ip6gre_net_ops = {
1648         .init = ip6gre_init_net,
1649         .exit_batch = ip6gre_exit_batch_net,
1650         .id   = &ip6gre_net_id,
1651         .size = sizeof(struct ip6gre_net),
1652 };
1653
1654 static int ip6gre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[],
1655                                   struct netlink_ext_ack *extack)
1656 {
1657         __be16 flags;
1658
1659         if (!data)
1660                 return 0;
1661
1662         flags = 0;
1663         if (data[IFLA_GRE_IFLAGS])
1664                 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
1665         if (data[IFLA_GRE_OFLAGS])
1666                 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
1667         if (flags & (GRE_VERSION|GRE_ROUTING))
1668                 return -EINVAL;
1669
1670         return 0;
1671 }
1672
1673 static int ip6gre_tap_validate(struct nlattr *tb[], struct nlattr *data[],
1674                                struct netlink_ext_ack *extack)
1675 {
1676         struct in6_addr daddr;
1677
1678         if (tb[IFLA_ADDRESS]) {
1679                 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
1680                         return -EINVAL;
1681                 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
1682                         return -EADDRNOTAVAIL;
1683         }
1684
1685         if (!data)
1686                 goto out;
1687
1688         if (data[IFLA_GRE_REMOTE]) {
1689                 daddr = nla_get_in6_addr(data[IFLA_GRE_REMOTE]);
1690                 if (ipv6_addr_any(&daddr))
1691                         return -EINVAL;
1692         }
1693
1694 out:
1695         return ip6gre_tunnel_validate(tb, data, extack);
1696 }
1697
1698 static int ip6erspan_tap_validate(struct nlattr *tb[], struct nlattr *data[],
1699                                   struct netlink_ext_ack *extack)
1700 {
1701         __be16 flags = 0;
1702         int ret, ver = 0;
1703
1704         if (!data)
1705                 return 0;
1706
1707         ret = ip6gre_tap_validate(tb, data, extack);
1708         if (ret)
1709                 return ret;
1710
1711         /* ERSPAN should only have GRE sequence and key flag */
1712         if (data[IFLA_GRE_OFLAGS])
1713                 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
1714         if (data[IFLA_GRE_IFLAGS])
1715                 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
1716         if (!data[IFLA_GRE_COLLECT_METADATA] &&
1717             flags != (GRE_SEQ | GRE_KEY))
1718                 return -EINVAL;
1719
1720         /* ERSPAN Session ID only has 10-bit. Since we reuse
1721          * 32-bit key field as ID, check it's range.
1722          */
1723         if (data[IFLA_GRE_IKEY] &&
1724             (ntohl(nla_get_be32(data[IFLA_GRE_IKEY])) & ~ID_MASK))
1725                 return -EINVAL;
1726
1727         if (data[IFLA_GRE_OKEY] &&
1728             (ntohl(nla_get_be32(data[IFLA_GRE_OKEY])) & ~ID_MASK))
1729                 return -EINVAL;
1730
1731         if (data[IFLA_GRE_ERSPAN_VER]) {
1732                 ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]);
1733                 if (ver != 1 && ver != 2)
1734                         return -EINVAL;
1735         }
1736
1737         if (ver == 1) {
1738                 if (data[IFLA_GRE_ERSPAN_INDEX]) {
1739                         u32 index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]);
1740
1741                         if (index & ~INDEX_MASK)
1742                                 return -EINVAL;
1743                 }
1744         } else if (ver == 2) {
1745                 if (data[IFLA_GRE_ERSPAN_DIR]) {
1746                         u16 dir = nla_get_u8(data[IFLA_GRE_ERSPAN_DIR]);
1747
1748                         if (dir & ~(DIR_MASK >> DIR_OFFSET))
1749                                 return -EINVAL;
1750                 }
1751
1752                 if (data[IFLA_GRE_ERSPAN_HWID]) {
1753                         u16 hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]);
1754
1755                         if (hwid & ~(HWID_MASK >> HWID_OFFSET))
1756                                 return -EINVAL;
1757                 }
1758         }
1759
1760         return 0;
1761 }
1762
1763 static void ip6erspan_set_version(struct nlattr *data[],
1764                                   struct __ip6_tnl_parm *parms)
1765 {
1766         if (!data)
1767                 return;
1768
1769         parms->erspan_ver = 1;
1770         if (data[IFLA_GRE_ERSPAN_VER])
1771                 parms->erspan_ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]);
1772
1773         if (parms->erspan_ver == 1) {
1774                 if (data[IFLA_GRE_ERSPAN_INDEX])
1775                         parms->index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]);
1776         } else if (parms->erspan_ver == 2) {
1777                 if (data[IFLA_GRE_ERSPAN_DIR])
1778                         parms->dir = nla_get_u8(data[IFLA_GRE_ERSPAN_DIR]);
1779                 if (data[IFLA_GRE_ERSPAN_HWID])
1780                         parms->hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]);
1781         }
1782 }
1783
1784 static void ip6gre_netlink_parms(struct nlattr *data[],
1785                                 struct __ip6_tnl_parm *parms)
1786 {
1787         memset(parms, 0, sizeof(*parms));
1788
1789         if (!data)
1790                 return;
1791
1792         if (data[IFLA_GRE_LINK])
1793                 parms->link = nla_get_u32(data[IFLA_GRE_LINK]);
1794
1795         if (data[IFLA_GRE_IFLAGS])
1796                 parms->i_flags = gre_flags_to_tnl_flags(
1797                                 nla_get_be16(data[IFLA_GRE_IFLAGS]));
1798
1799         if (data[IFLA_GRE_OFLAGS])
1800                 parms->o_flags = gre_flags_to_tnl_flags(
1801                                 nla_get_be16(data[IFLA_GRE_OFLAGS]));
1802
1803         if (data[IFLA_GRE_IKEY])
1804                 parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]);
1805
1806         if (data[IFLA_GRE_OKEY])
1807                 parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]);
1808
1809         if (data[IFLA_GRE_LOCAL])
1810                 parms->laddr = nla_get_in6_addr(data[IFLA_GRE_LOCAL]);
1811
1812         if (data[IFLA_GRE_REMOTE])
1813                 parms->raddr = nla_get_in6_addr(data[IFLA_GRE_REMOTE]);
1814
1815         if (data[IFLA_GRE_TTL])
1816                 parms->hop_limit = nla_get_u8(data[IFLA_GRE_TTL]);
1817
1818         if (data[IFLA_GRE_ENCAP_LIMIT])
1819                 parms->encap_limit = nla_get_u8(data[IFLA_GRE_ENCAP_LIMIT]);
1820
1821         if (data[IFLA_GRE_FLOWINFO])
1822                 parms->flowinfo = nla_get_be32(data[IFLA_GRE_FLOWINFO]);
1823
1824         if (data[IFLA_GRE_FLAGS])
1825                 parms->flags = nla_get_u32(data[IFLA_GRE_FLAGS]);
1826
1827         if (data[IFLA_GRE_FWMARK])
1828                 parms->fwmark = nla_get_u32(data[IFLA_GRE_FWMARK]);
1829
1830         if (data[IFLA_GRE_COLLECT_METADATA])
1831                 parms->collect_md = true;
1832 }
1833
1834 static int ip6gre_tap_init(struct net_device *dev)
1835 {
1836         int ret;
1837
1838         ret = ip6gre_tunnel_init_common(dev);
1839         if (ret)
1840                 return ret;
1841
1842         dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1843
1844         return 0;
1845 }
1846
1847 static const struct net_device_ops ip6gre_tap_netdev_ops = {
1848         .ndo_init = ip6gre_tap_init,
1849         .ndo_uninit = ip6gre_tunnel_uninit,
1850         .ndo_start_xmit = ip6gre_tunnel_xmit,
1851         .ndo_set_mac_address = eth_mac_addr,
1852         .ndo_validate_addr = eth_validate_addr,
1853         .ndo_change_mtu = ip6_tnl_change_mtu,
1854         .ndo_get_stats64 = dev_get_tstats64,
1855         .ndo_get_iflink = ip6_tnl_get_iflink,
1856 };
1857
1858 static int ip6erspan_calc_hlen(struct ip6_tnl *tunnel)
1859 {
1860         int t_hlen;
1861
1862         tunnel->tun_hlen = 8;
1863         tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen +
1864                        erspan_hdr_len(tunnel->parms.erspan_ver);
1865
1866         t_hlen = tunnel->hlen + sizeof(struct ipv6hdr);
1867         tunnel->dev->needed_headroom = LL_MAX_HEADER + t_hlen;
1868         return t_hlen;
1869 }
1870
1871 static int ip6erspan_tap_init(struct net_device *dev)
1872 {
1873         struct ip6_tnl *tunnel;
1874         int t_hlen;
1875         int ret;
1876
1877         tunnel = netdev_priv(dev);
1878
1879         tunnel->dev = dev;
1880         tunnel->net = dev_net(dev);
1881         strcpy(tunnel->parms.name, dev->name);
1882
1883         dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1884         if (!dev->tstats)
1885                 return -ENOMEM;
1886
1887         ret = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
1888         if (ret)
1889                 goto cleanup_alloc_pcpu_stats;
1890
1891         ret = gro_cells_init(&tunnel->gro_cells, dev);
1892         if (ret)
1893                 goto cleanup_dst_cache_init;
1894
1895         t_hlen = ip6erspan_calc_hlen(tunnel);
1896         dev->mtu = ETH_DATA_LEN - t_hlen;
1897         if (dev->type == ARPHRD_ETHER)
1898                 dev->mtu -= ETH_HLEN;
1899         if (!(tunnel->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1900                 dev->mtu -= 8;
1901
1902         dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1903         ip6erspan_tnl_link_config(tunnel, 1);
1904
1905         dev_hold(dev);
1906         return 0;
1907
1908 cleanup_dst_cache_init:
1909         dst_cache_destroy(&tunnel->dst_cache);
1910 cleanup_alloc_pcpu_stats:
1911         free_percpu(dev->tstats);
1912         dev->tstats = NULL;
1913         return ret;
1914 }
1915
1916 static const struct net_device_ops ip6erspan_netdev_ops = {
1917         .ndo_init =             ip6erspan_tap_init,
1918         .ndo_uninit =           ip6erspan_tunnel_uninit,
1919         .ndo_start_xmit =       ip6erspan_tunnel_xmit,
1920         .ndo_set_mac_address =  eth_mac_addr,
1921         .ndo_validate_addr =    eth_validate_addr,
1922         .ndo_change_mtu =       ip6_tnl_change_mtu,
1923         .ndo_get_stats64 =      dev_get_tstats64,
1924         .ndo_get_iflink =       ip6_tnl_get_iflink,
1925 };
1926
1927 static void ip6gre_tap_setup(struct net_device *dev)
1928 {
1929
1930         ether_setup(dev);
1931
1932         dev->max_mtu = 0;
1933         dev->netdev_ops = &ip6gre_tap_netdev_ops;
1934         dev->needs_free_netdev = true;
1935         dev->priv_destructor = ip6gre_dev_free;
1936
1937         dev->priv_flags &= ~IFF_TX_SKB_SHARING;
1938         dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1939         netif_keep_dst(dev);
1940 }
1941
1942 static bool ip6gre_netlink_encap_parms(struct nlattr *data[],
1943                                        struct ip_tunnel_encap *ipencap)
1944 {
1945         bool ret = false;
1946
1947         memset(ipencap, 0, sizeof(*ipencap));
1948
1949         if (!data)
1950                 return ret;
1951
1952         if (data[IFLA_GRE_ENCAP_TYPE]) {
1953                 ret = true;
1954                 ipencap->type = nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]);
1955         }
1956
1957         if (data[IFLA_GRE_ENCAP_FLAGS]) {
1958                 ret = true;
1959                 ipencap->flags = nla_get_u16(data[IFLA_GRE_ENCAP_FLAGS]);
1960         }
1961
1962         if (data[IFLA_GRE_ENCAP_SPORT]) {
1963                 ret = true;
1964                 ipencap->sport = nla_get_be16(data[IFLA_GRE_ENCAP_SPORT]);
1965         }
1966
1967         if (data[IFLA_GRE_ENCAP_DPORT]) {
1968                 ret = true;
1969                 ipencap->dport = nla_get_be16(data[IFLA_GRE_ENCAP_DPORT]);
1970         }
1971
1972         return ret;
1973 }
1974
1975 static int ip6gre_newlink_common(struct net *src_net, struct net_device *dev,
1976                                  struct nlattr *tb[], struct nlattr *data[],
1977                                  struct netlink_ext_ack *extack)
1978 {
1979         struct ip6_tnl *nt;
1980         struct ip_tunnel_encap ipencap;
1981         int err;
1982
1983         nt = netdev_priv(dev);
1984
1985         if (ip6gre_netlink_encap_parms(data, &ipencap)) {
1986                 int err = ip6_tnl_encap_setup(nt, &ipencap);
1987
1988                 if (err < 0)
1989                         return err;
1990         }
1991
1992         if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS])
1993                 eth_hw_addr_random(dev);
1994
1995         nt->dev = dev;
1996         nt->net = dev_net(dev);
1997
1998         err = register_netdevice(dev);
1999         if (err)
2000                 goto out;
2001
2002         if (tb[IFLA_MTU])
2003                 ip6_tnl_change_mtu(dev, nla_get_u32(tb[IFLA_MTU]));
2004
2005 out:
2006         return err;
2007 }
2008
2009 static int ip6gre_newlink(struct net *src_net, struct net_device *dev,
2010                           struct nlattr *tb[], struct nlattr *data[],
2011                           struct netlink_ext_ack *extack)
2012 {
2013         struct ip6_tnl *nt = netdev_priv(dev);
2014         struct net *net = dev_net(dev);
2015         struct ip6gre_net *ign;
2016         int err;
2017
2018         ip6gre_netlink_parms(data, &nt->parms);
2019         ign = net_generic(net, ip6gre_net_id);
2020
2021         if (nt->parms.collect_md) {
2022                 if (rtnl_dereference(ign->collect_md_tun))
2023                         return -EEXIST;
2024         } else {
2025                 if (ip6gre_tunnel_find(net, &nt->parms, dev->type))
2026                         return -EEXIST;
2027         }
2028
2029         err = ip6gre_newlink_common(src_net, dev, tb, data, extack);
2030         if (!err) {
2031                 ip6gre_tnl_link_config(nt, !tb[IFLA_MTU]);
2032                 ip6gre_tunnel_link_md(ign, nt);
2033                 ip6gre_tunnel_link(net_generic(net, ip6gre_net_id), nt);
2034         }
2035         return err;
2036 }
2037
2038 static struct ip6_tnl *
2039 ip6gre_changelink_common(struct net_device *dev, struct nlattr *tb[],
2040                          struct nlattr *data[], struct __ip6_tnl_parm *p_p,
2041                          struct netlink_ext_ack *extack)
2042 {
2043         struct ip6_tnl *t, *nt = netdev_priv(dev);
2044         struct net *net = nt->net;
2045         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
2046         struct ip_tunnel_encap ipencap;
2047
2048         if (dev == ign->fb_tunnel_dev)
2049                 return ERR_PTR(-EINVAL);
2050
2051         if (ip6gre_netlink_encap_parms(data, &ipencap)) {
2052                 int err = ip6_tnl_encap_setup(nt, &ipencap);
2053
2054                 if (err < 0)
2055                         return ERR_PTR(err);
2056         }
2057
2058         ip6gre_netlink_parms(data, p_p);
2059
2060         t = ip6gre_tunnel_locate(net, p_p, 0);
2061
2062         if (t) {
2063                 if (t->dev != dev)
2064                         return ERR_PTR(-EEXIST);
2065         } else {
2066                 t = nt;
2067         }
2068
2069         return t;
2070 }
2071
2072 static int ip6gre_changelink(struct net_device *dev, struct nlattr *tb[],
2073                              struct nlattr *data[],
2074                              struct netlink_ext_ack *extack)
2075 {
2076         struct ip6_tnl *t = netdev_priv(dev);
2077         struct ip6gre_net *ign = net_generic(t->net, ip6gre_net_id);
2078         struct __ip6_tnl_parm p;
2079
2080         t = ip6gre_changelink_common(dev, tb, data, &p, extack);
2081         if (IS_ERR(t))
2082                 return PTR_ERR(t);
2083
2084         ip6gre_tunnel_unlink_md(ign, t);
2085         ip6gre_tunnel_unlink(ign, t);
2086         ip6gre_tnl_change(t, &p, !tb[IFLA_MTU]);
2087         ip6gre_tunnel_link_md(ign, t);
2088         ip6gre_tunnel_link(ign, t);
2089         return 0;
2090 }
2091
2092 static void ip6gre_dellink(struct net_device *dev, struct list_head *head)
2093 {
2094         struct net *net = dev_net(dev);
2095         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
2096
2097         if (dev != ign->fb_tunnel_dev)
2098                 unregister_netdevice_queue(dev, head);
2099 }
2100
2101 static size_t ip6gre_get_size(const struct net_device *dev)
2102 {
2103         return
2104                 /* IFLA_GRE_LINK */
2105                 nla_total_size(4) +
2106                 /* IFLA_GRE_IFLAGS */
2107                 nla_total_size(2) +
2108                 /* IFLA_GRE_OFLAGS */
2109                 nla_total_size(2) +
2110                 /* IFLA_GRE_IKEY */
2111                 nla_total_size(4) +
2112                 /* IFLA_GRE_OKEY */
2113                 nla_total_size(4) +
2114                 /* IFLA_GRE_LOCAL */
2115                 nla_total_size(sizeof(struct in6_addr)) +
2116                 /* IFLA_GRE_REMOTE */
2117                 nla_total_size(sizeof(struct in6_addr)) +
2118                 /* IFLA_GRE_TTL */
2119                 nla_total_size(1) +
2120                 /* IFLA_GRE_ENCAP_LIMIT */
2121                 nla_total_size(1) +
2122                 /* IFLA_GRE_FLOWINFO */
2123                 nla_total_size(4) +
2124                 /* IFLA_GRE_FLAGS */
2125                 nla_total_size(4) +
2126                 /* IFLA_GRE_ENCAP_TYPE */
2127                 nla_total_size(2) +
2128                 /* IFLA_GRE_ENCAP_FLAGS */
2129                 nla_total_size(2) +
2130                 /* IFLA_GRE_ENCAP_SPORT */
2131                 nla_total_size(2) +
2132                 /* IFLA_GRE_ENCAP_DPORT */
2133                 nla_total_size(2) +
2134                 /* IFLA_GRE_COLLECT_METADATA */
2135                 nla_total_size(0) +
2136                 /* IFLA_GRE_FWMARK */
2137                 nla_total_size(4) +
2138                 /* IFLA_GRE_ERSPAN_INDEX */
2139                 nla_total_size(4) +
2140                 0;
2141 }
2142
2143 static int ip6gre_fill_info(struct sk_buff *skb, const struct net_device *dev)
2144 {
2145         struct ip6_tnl *t = netdev_priv(dev);
2146         struct __ip6_tnl_parm *p = &t->parms;
2147         __be16 o_flags = p->o_flags;
2148
2149         if (p->erspan_ver == 1 || p->erspan_ver == 2) {
2150                 if (!p->collect_md)
2151                         o_flags |= TUNNEL_KEY;
2152
2153                 if (nla_put_u8(skb, IFLA_GRE_ERSPAN_VER, p->erspan_ver))
2154                         goto nla_put_failure;
2155
2156                 if (p->erspan_ver == 1) {
2157                         if (nla_put_u32(skb, IFLA_GRE_ERSPAN_INDEX, p->index))
2158                                 goto nla_put_failure;
2159                 } else {
2160                         if (nla_put_u8(skb, IFLA_GRE_ERSPAN_DIR, p->dir))
2161                                 goto nla_put_failure;
2162                         if (nla_put_u16(skb, IFLA_GRE_ERSPAN_HWID, p->hwid))
2163                                 goto nla_put_failure;
2164                 }
2165         }
2166
2167         if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) ||
2168             nla_put_be16(skb, IFLA_GRE_IFLAGS,
2169                          gre_tnl_flags_to_gre_flags(p->i_flags)) ||
2170             nla_put_be16(skb, IFLA_GRE_OFLAGS,
2171                          gre_tnl_flags_to_gre_flags(o_flags)) ||
2172             nla_put_be32(skb, IFLA_GRE_IKEY, p->i_key) ||
2173             nla_put_be32(skb, IFLA_GRE_OKEY, p->o_key) ||
2174             nla_put_in6_addr(skb, IFLA_GRE_LOCAL, &p->laddr) ||
2175             nla_put_in6_addr(skb, IFLA_GRE_REMOTE, &p->raddr) ||
2176             nla_put_u8(skb, IFLA_GRE_TTL, p->hop_limit) ||
2177             nla_put_u8(skb, IFLA_GRE_ENCAP_LIMIT, p->encap_limit) ||
2178             nla_put_be32(skb, IFLA_GRE_FLOWINFO, p->flowinfo) ||
2179             nla_put_u32(skb, IFLA_GRE_FLAGS, p->flags) ||
2180             nla_put_u32(skb, IFLA_GRE_FWMARK, p->fwmark))
2181                 goto nla_put_failure;
2182
2183         if (nla_put_u16(skb, IFLA_GRE_ENCAP_TYPE,
2184                         t->encap.type) ||
2185             nla_put_be16(skb, IFLA_GRE_ENCAP_SPORT,
2186                          t->encap.sport) ||
2187             nla_put_be16(skb, IFLA_GRE_ENCAP_DPORT,
2188                          t->encap.dport) ||
2189             nla_put_u16(skb, IFLA_GRE_ENCAP_FLAGS,
2190                         t->encap.flags))
2191                 goto nla_put_failure;
2192
2193         if (p->collect_md) {
2194                 if (nla_put_flag(skb, IFLA_GRE_COLLECT_METADATA))
2195                         goto nla_put_failure;
2196         }
2197
2198         return 0;
2199
2200 nla_put_failure:
2201         return -EMSGSIZE;
2202 }
2203
2204 static const struct nla_policy ip6gre_policy[IFLA_GRE_MAX + 1] = {
2205         [IFLA_GRE_LINK]        = { .type = NLA_U32 },
2206         [IFLA_GRE_IFLAGS]      = { .type = NLA_U16 },
2207         [IFLA_GRE_OFLAGS]      = { .type = NLA_U16 },
2208         [IFLA_GRE_IKEY]        = { .type = NLA_U32 },
2209         [IFLA_GRE_OKEY]        = { .type = NLA_U32 },
2210         [IFLA_GRE_LOCAL]       = { .len = sizeof_field(struct ipv6hdr, saddr) },
2211         [IFLA_GRE_REMOTE]      = { .len = sizeof_field(struct ipv6hdr, daddr) },
2212         [IFLA_GRE_TTL]         = { .type = NLA_U8 },
2213         [IFLA_GRE_ENCAP_LIMIT] = { .type = NLA_U8 },
2214         [IFLA_GRE_FLOWINFO]    = { .type = NLA_U32 },
2215         [IFLA_GRE_FLAGS]       = { .type = NLA_U32 },
2216         [IFLA_GRE_ENCAP_TYPE]   = { .type = NLA_U16 },
2217         [IFLA_GRE_ENCAP_FLAGS]  = { .type = NLA_U16 },
2218         [IFLA_GRE_ENCAP_SPORT]  = { .type = NLA_U16 },
2219         [IFLA_GRE_ENCAP_DPORT]  = { .type = NLA_U16 },
2220         [IFLA_GRE_COLLECT_METADATA] = { .type = NLA_FLAG },
2221         [IFLA_GRE_FWMARK]       = { .type = NLA_U32 },
2222         [IFLA_GRE_ERSPAN_INDEX] = { .type = NLA_U32 },
2223         [IFLA_GRE_ERSPAN_VER]   = { .type = NLA_U8 },
2224         [IFLA_GRE_ERSPAN_DIR]   = { .type = NLA_U8 },
2225         [IFLA_GRE_ERSPAN_HWID]  = { .type = NLA_U16 },
2226 };
2227
2228 static void ip6erspan_tap_setup(struct net_device *dev)
2229 {
2230         ether_setup(dev);
2231
2232         dev->max_mtu = 0;
2233         dev->netdev_ops = &ip6erspan_netdev_ops;
2234         dev->needs_free_netdev = true;
2235         dev->priv_destructor = ip6gre_dev_free;
2236
2237         dev->priv_flags &= ~IFF_TX_SKB_SHARING;
2238         dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
2239         netif_keep_dst(dev);
2240 }
2241
2242 static int ip6erspan_newlink(struct net *src_net, struct net_device *dev,
2243                              struct nlattr *tb[], struct nlattr *data[],
2244                              struct netlink_ext_ack *extack)
2245 {
2246         struct ip6_tnl *nt = netdev_priv(dev);
2247         struct net *net = dev_net(dev);
2248         struct ip6gre_net *ign;
2249         int err;
2250
2251         ip6gre_netlink_parms(data, &nt->parms);
2252         ip6erspan_set_version(data, &nt->parms);
2253         ign = net_generic(net, ip6gre_net_id);
2254
2255         if (nt->parms.collect_md) {
2256                 if (rtnl_dereference(ign->collect_md_tun_erspan))
2257                         return -EEXIST;
2258         } else {
2259                 if (ip6gre_tunnel_find(net, &nt->parms, dev->type))
2260                         return -EEXIST;
2261         }
2262
2263         err = ip6gre_newlink_common(src_net, dev, tb, data, extack);
2264         if (!err) {
2265                 ip6erspan_tnl_link_config(nt, !tb[IFLA_MTU]);
2266                 ip6erspan_tunnel_link_md(ign, nt);
2267                 ip6gre_tunnel_link(net_generic(net, ip6gre_net_id), nt);
2268         }
2269         return err;
2270 }
2271
2272 static void ip6erspan_tnl_link_config(struct ip6_tnl *t, int set_mtu)
2273 {
2274         ip6gre_tnl_link_config_common(t);
2275         ip6gre_tnl_link_config_route(t, set_mtu, ip6erspan_calc_hlen(t));
2276 }
2277
2278 static int ip6erspan_tnl_change(struct ip6_tnl *t,
2279                                 const struct __ip6_tnl_parm *p, int set_mtu)
2280 {
2281         ip6gre_tnl_copy_tnl_parm(t, p);
2282         ip6erspan_tnl_link_config(t, set_mtu);
2283         return 0;
2284 }
2285
2286 static int ip6erspan_changelink(struct net_device *dev, struct nlattr *tb[],
2287                                 struct nlattr *data[],
2288                                 struct netlink_ext_ack *extack)
2289 {
2290         struct ip6gre_net *ign = net_generic(dev_net(dev), ip6gre_net_id);
2291         struct __ip6_tnl_parm p;
2292         struct ip6_tnl *t;
2293
2294         t = ip6gre_changelink_common(dev, tb, data, &p, extack);
2295         if (IS_ERR(t))
2296                 return PTR_ERR(t);
2297
2298         ip6erspan_set_version(data, &p);
2299         ip6gre_tunnel_unlink_md(ign, t);
2300         ip6gre_tunnel_unlink(ign, t);
2301         ip6erspan_tnl_change(t, &p, !tb[IFLA_MTU]);
2302         ip6erspan_tunnel_link_md(ign, t);
2303         ip6gre_tunnel_link(ign, t);
2304         return 0;
2305 }
2306
2307 static struct rtnl_link_ops ip6gre_link_ops __read_mostly = {
2308         .kind           = "ip6gre",
2309         .maxtype        = IFLA_GRE_MAX,
2310         .policy         = ip6gre_policy,
2311         .priv_size      = sizeof(struct ip6_tnl),
2312         .setup          = ip6gre_tunnel_setup,
2313         .validate       = ip6gre_tunnel_validate,
2314         .newlink        = ip6gre_newlink,
2315         .changelink     = ip6gre_changelink,
2316         .dellink        = ip6gre_dellink,
2317         .get_size       = ip6gre_get_size,
2318         .fill_info      = ip6gre_fill_info,
2319         .get_link_net   = ip6_tnl_get_link_net,
2320 };
2321
2322 static struct rtnl_link_ops ip6gre_tap_ops __read_mostly = {
2323         .kind           = "ip6gretap",
2324         .maxtype        = IFLA_GRE_MAX,
2325         .policy         = ip6gre_policy,
2326         .priv_size      = sizeof(struct ip6_tnl),
2327         .setup          = ip6gre_tap_setup,
2328         .validate       = ip6gre_tap_validate,
2329         .newlink        = ip6gre_newlink,
2330         .changelink     = ip6gre_changelink,
2331         .get_size       = ip6gre_get_size,
2332         .fill_info      = ip6gre_fill_info,
2333         .get_link_net   = ip6_tnl_get_link_net,
2334 };
2335
2336 static struct rtnl_link_ops ip6erspan_tap_ops __read_mostly = {
2337         .kind           = "ip6erspan",
2338         .maxtype        = IFLA_GRE_MAX,
2339         .policy         = ip6gre_policy,
2340         .priv_size      = sizeof(struct ip6_tnl),
2341         .setup          = ip6erspan_tap_setup,
2342         .validate       = ip6erspan_tap_validate,
2343         .newlink        = ip6erspan_newlink,
2344         .changelink     = ip6erspan_changelink,
2345         .get_size       = ip6gre_get_size,
2346         .fill_info      = ip6gre_fill_info,
2347         .get_link_net   = ip6_tnl_get_link_net,
2348 };
2349
2350 /*
2351  *      And now the modules code and kernel interface.
2352  */
2353
2354 static int __init ip6gre_init(void)
2355 {
2356         int err;
2357
2358         pr_info("GRE over IPv6 tunneling driver\n");
2359
2360         err = register_pernet_device(&ip6gre_net_ops);
2361         if (err < 0)
2362                 return err;
2363
2364         err = inet6_add_protocol(&ip6gre_protocol, IPPROTO_GRE);
2365         if (err < 0) {
2366                 pr_info("%s: can't add protocol\n", __func__);
2367                 goto add_proto_failed;
2368         }
2369
2370         err = rtnl_link_register(&ip6gre_link_ops);
2371         if (err < 0)
2372                 goto rtnl_link_failed;
2373
2374         err = rtnl_link_register(&ip6gre_tap_ops);
2375         if (err < 0)
2376                 goto tap_ops_failed;
2377
2378         err = rtnl_link_register(&ip6erspan_tap_ops);
2379         if (err < 0)
2380                 goto erspan_link_failed;
2381
2382 out:
2383         return err;
2384
2385 erspan_link_failed:
2386         rtnl_link_unregister(&ip6gre_tap_ops);
2387 tap_ops_failed:
2388         rtnl_link_unregister(&ip6gre_link_ops);
2389 rtnl_link_failed:
2390         inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE);
2391 add_proto_failed:
2392         unregister_pernet_device(&ip6gre_net_ops);
2393         goto out;
2394 }
2395
2396 static void __exit ip6gre_fini(void)
2397 {
2398         rtnl_link_unregister(&ip6gre_tap_ops);
2399         rtnl_link_unregister(&ip6gre_link_ops);
2400         rtnl_link_unregister(&ip6erspan_tap_ops);
2401         inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE);
2402         unregister_pernet_device(&ip6gre_net_ops);
2403 }
2404
2405 module_init(ip6gre_init);
2406 module_exit(ip6gre_fini);
2407 MODULE_LICENSE("GPL");
2408 MODULE_AUTHOR("D. Kozlov (xeb@mail.ru)");
2409 MODULE_DESCRIPTION("GRE over IPv6 tunneling device");
2410 MODULE_ALIAS_RTNL_LINK("ip6gre");
2411 MODULE_ALIAS_RTNL_LINK("ip6gretap");
2412 MODULE_ALIAS_RTNL_LINK("ip6erspan");
2413 MODULE_ALIAS_NETDEV("ip6gre0");