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_ioctl(struct net_device *dev,
1262         struct ifreq *ifr, int cmd)
1263 {
1264         int err = 0;
1265         struct ip6_tnl_parm2 p;
1266         struct __ip6_tnl_parm p1;
1267         struct ip6_tnl *t = netdev_priv(dev);
1268         struct net *net = t->net;
1269         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1270
1271         memset(&p1, 0, sizeof(p1));
1272
1273         switch (cmd) {
1274         case SIOCGETTUNNEL:
1275                 if (dev == ign->fb_tunnel_dev) {
1276                         if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
1277                                 err = -EFAULT;
1278                                 break;
1279                         }
1280                         ip6gre_tnl_parm_from_user(&p1, &p);
1281                         t = ip6gre_tunnel_locate(net, &p1, 0);
1282                         if (!t)
1283                                 t = netdev_priv(dev);
1284                 }
1285                 memset(&p, 0, sizeof(p));
1286                 ip6gre_tnl_parm_to_user(&p, &t->parms);
1287                 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
1288                         err = -EFAULT;
1289                 break;
1290
1291         case SIOCADDTUNNEL:
1292         case SIOCCHGTUNNEL:
1293                 err = -EPERM;
1294                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1295                         goto done;
1296
1297                 err = -EFAULT;
1298                 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
1299                         goto done;
1300
1301                 err = -EINVAL;
1302                 if ((p.i_flags|p.o_flags)&(GRE_VERSION|GRE_ROUTING))
1303                         goto done;
1304
1305                 if (!(p.i_flags&GRE_KEY))
1306                         p.i_key = 0;
1307                 if (!(p.o_flags&GRE_KEY))
1308                         p.o_key = 0;
1309
1310                 ip6gre_tnl_parm_from_user(&p1, &p);
1311                 t = ip6gre_tunnel_locate(net, &p1, cmd == SIOCADDTUNNEL);
1312
1313                 if (dev != ign->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
1314                         if (t) {
1315                                 if (t->dev != dev) {
1316                                         err = -EEXIST;
1317                                         break;
1318                                 }
1319                         } else {
1320                                 t = netdev_priv(dev);
1321
1322                                 ip6gre_tunnel_unlink(ign, t);
1323                                 synchronize_net();
1324                                 ip6gre_tnl_change(t, &p1, 1);
1325                                 ip6gre_tunnel_link(ign, t);
1326                                 netdev_state_change(dev);
1327                         }
1328                 }
1329
1330                 if (t) {
1331                         err = 0;
1332
1333                         memset(&p, 0, sizeof(p));
1334                         ip6gre_tnl_parm_to_user(&p, &t->parms);
1335                         if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
1336                                 err = -EFAULT;
1337                 } else
1338                         err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
1339                 break;
1340
1341         case SIOCDELTUNNEL:
1342                 err = -EPERM;
1343                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1344                         goto done;
1345
1346                 if (dev == ign->fb_tunnel_dev) {
1347                         err = -EFAULT;
1348                         if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
1349                                 goto done;
1350                         err = -ENOENT;
1351                         ip6gre_tnl_parm_from_user(&p1, &p);
1352                         t = ip6gre_tunnel_locate(net, &p1, 0);
1353                         if (!t)
1354                                 goto done;
1355                         err = -EPERM;
1356                         if (t == netdev_priv(ign->fb_tunnel_dev))
1357                                 goto done;
1358                         dev = t->dev;
1359                 }
1360                 unregister_netdevice(dev);
1361                 err = 0;
1362                 break;
1363
1364         default:
1365                 err = -EINVAL;
1366         }
1367
1368 done:
1369         return err;
1370 }
1371
1372 static int ip6gre_header(struct sk_buff *skb, struct net_device *dev,
1373                          unsigned short type, const void *daddr,
1374                          const void *saddr, unsigned int len)
1375 {
1376         struct ip6_tnl *t = netdev_priv(dev);
1377         struct ipv6hdr *ipv6h;
1378         __be16 *p;
1379
1380         ipv6h = skb_push(skb, t->hlen + sizeof(*ipv6h));
1381         ip6_flow_hdr(ipv6h, 0, ip6_make_flowlabel(dev_net(dev), skb,
1382                                                   t->fl.u.ip6.flowlabel,
1383                                                   true, &t->fl.u.ip6));
1384         ipv6h->hop_limit = t->parms.hop_limit;
1385         ipv6h->nexthdr = NEXTHDR_GRE;
1386         ipv6h->saddr = t->parms.laddr;
1387         ipv6h->daddr = t->parms.raddr;
1388
1389         p = (__be16 *)(ipv6h + 1);
1390         p[0] = t->parms.o_flags;
1391         p[1] = htons(type);
1392
1393         /*
1394          *      Set the source hardware address.
1395          */
1396
1397         if (saddr)
1398                 memcpy(&ipv6h->saddr, saddr, sizeof(struct in6_addr));
1399         if (daddr)
1400                 memcpy(&ipv6h->daddr, daddr, sizeof(struct in6_addr));
1401         if (!ipv6_addr_any(&ipv6h->daddr))
1402                 return t->hlen;
1403
1404         return -t->hlen;
1405 }
1406
1407 static const struct header_ops ip6gre_header_ops = {
1408         .create = ip6gre_header,
1409 };
1410
1411 static const struct net_device_ops ip6gre_netdev_ops = {
1412         .ndo_init               = ip6gre_tunnel_init,
1413         .ndo_uninit             = ip6gre_tunnel_uninit,
1414         .ndo_start_xmit         = ip6gre_tunnel_xmit,
1415         .ndo_do_ioctl           = ip6gre_tunnel_ioctl,
1416         .ndo_change_mtu         = ip6_tnl_change_mtu,
1417         .ndo_get_stats64        = ip_tunnel_get_stats64,
1418         .ndo_get_iflink         = ip6_tnl_get_iflink,
1419 };
1420
1421 static void ip6gre_dev_free(struct net_device *dev)
1422 {
1423         struct ip6_tnl *t = netdev_priv(dev);
1424
1425         gro_cells_destroy(&t->gro_cells);
1426         dst_cache_destroy(&t->dst_cache);
1427         free_percpu(dev->tstats);
1428 }
1429
1430 static void ip6gre_tunnel_setup(struct net_device *dev)
1431 {
1432         dev->netdev_ops = &ip6gre_netdev_ops;
1433         dev->needs_free_netdev = true;
1434         dev->priv_destructor = ip6gre_dev_free;
1435
1436         dev->type = ARPHRD_IP6GRE;
1437
1438         dev->flags |= IFF_NOARP;
1439         dev->addr_len = sizeof(struct in6_addr);
1440         netif_keep_dst(dev);
1441         /* This perm addr will be used as interface identifier by IPv6 */
1442         dev->addr_assign_type = NET_ADDR_RANDOM;
1443         eth_random_addr(dev->perm_addr);
1444 }
1445
1446 #define GRE6_FEATURES (NETIF_F_SG |             \
1447                        NETIF_F_FRAGLIST |       \
1448                        NETIF_F_HIGHDMA |        \
1449                        NETIF_F_HW_CSUM)
1450
1451 static void ip6gre_tnl_init_features(struct net_device *dev)
1452 {
1453         struct ip6_tnl *nt = netdev_priv(dev);
1454
1455         dev->features           |= GRE6_FEATURES;
1456         dev->hw_features        |= GRE6_FEATURES;
1457
1458         if (!(nt->parms.o_flags & TUNNEL_SEQ)) {
1459                 /* TCP offload with GRE SEQ is not supported, nor
1460                  * can we support 2 levels of outer headers requiring
1461                  * an update.
1462                  */
1463                 if (!(nt->parms.o_flags & TUNNEL_CSUM) ||
1464                     nt->encap.type == TUNNEL_ENCAP_NONE) {
1465                         dev->features    |= NETIF_F_GSO_SOFTWARE;
1466                         dev->hw_features |= NETIF_F_GSO_SOFTWARE;
1467                 }
1468
1469                 /* Can use a lockless transmit, unless we generate
1470                  * output sequences
1471                  */
1472                 dev->features |= NETIF_F_LLTX;
1473         }
1474 }
1475
1476 static int ip6gre_tunnel_init_common(struct net_device *dev)
1477 {
1478         struct ip6_tnl *tunnel;
1479         int ret;
1480         int t_hlen;
1481
1482         tunnel = netdev_priv(dev);
1483
1484         tunnel->dev = dev;
1485         tunnel->net = dev_net(dev);
1486         strcpy(tunnel->parms.name, dev->name);
1487
1488         dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1489         if (!dev->tstats)
1490                 return -ENOMEM;
1491
1492         ret = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
1493         if (ret)
1494                 goto cleanup_alloc_pcpu_stats;
1495
1496         ret = gro_cells_init(&tunnel->gro_cells, dev);
1497         if (ret)
1498                 goto cleanup_dst_cache_init;
1499
1500         t_hlen = ip6gre_calc_hlen(tunnel);
1501         dev->mtu = ETH_DATA_LEN - t_hlen;
1502         if (dev->type == ARPHRD_ETHER)
1503                 dev->mtu -= ETH_HLEN;
1504         if (!(tunnel->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1505                 dev->mtu -= 8;
1506
1507         if (tunnel->parms.collect_md) {
1508                 netif_keep_dst(dev);
1509         }
1510         ip6gre_tnl_init_features(dev);
1511
1512         dev_hold(dev);
1513         return 0;
1514
1515 cleanup_dst_cache_init:
1516         dst_cache_destroy(&tunnel->dst_cache);
1517 cleanup_alloc_pcpu_stats:
1518         free_percpu(dev->tstats);
1519         dev->tstats = NULL;
1520         return ret;
1521 }
1522
1523 static int ip6gre_tunnel_init(struct net_device *dev)
1524 {
1525         struct ip6_tnl *tunnel;
1526         int ret;
1527
1528         ret = ip6gre_tunnel_init_common(dev);
1529         if (ret)
1530                 return ret;
1531
1532         tunnel = netdev_priv(dev);
1533
1534         if (tunnel->parms.collect_md)
1535                 return 0;
1536
1537         memcpy(dev->dev_addr, &tunnel->parms.laddr, sizeof(struct in6_addr));
1538         memcpy(dev->broadcast, &tunnel->parms.raddr, sizeof(struct in6_addr));
1539
1540         if (ipv6_addr_any(&tunnel->parms.raddr))
1541                 dev->header_ops = &ip6gre_header_ops;
1542
1543         return 0;
1544 }
1545
1546 static void ip6gre_fb_tunnel_init(struct net_device *dev)
1547 {
1548         struct ip6_tnl *tunnel = netdev_priv(dev);
1549
1550         tunnel->dev = dev;
1551         tunnel->net = dev_net(dev);
1552         strcpy(tunnel->parms.name, dev->name);
1553
1554         tunnel->hlen            = sizeof(struct ipv6hdr) + 4;
1555 }
1556
1557 static struct inet6_protocol ip6gre_protocol __read_mostly = {
1558         .handler     = gre_rcv,
1559         .err_handler = ip6gre_err,
1560         .flags       = INET6_PROTO_FINAL,
1561 };
1562
1563 static void ip6gre_destroy_tunnels(struct net *net, struct list_head *head)
1564 {
1565         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1566         struct net_device *dev, *aux;
1567         int prio;
1568
1569         for_each_netdev_safe(net, dev, aux)
1570                 if (dev->rtnl_link_ops == &ip6gre_link_ops ||
1571                     dev->rtnl_link_ops == &ip6gre_tap_ops ||
1572                     dev->rtnl_link_ops == &ip6erspan_tap_ops)
1573                         unregister_netdevice_queue(dev, head);
1574
1575         for (prio = 0; prio < 4; prio++) {
1576                 int h;
1577                 for (h = 0; h < IP6_GRE_HASH_SIZE; h++) {
1578                         struct ip6_tnl *t;
1579
1580                         t = rtnl_dereference(ign->tunnels[prio][h]);
1581
1582                         while (t) {
1583                                 /* If dev is in the same netns, it has already
1584                                  * been added to the list by the previous loop.
1585                                  */
1586                                 if (!net_eq(dev_net(t->dev), net))
1587                                         unregister_netdevice_queue(t->dev,
1588                                                                    head);
1589                                 t = rtnl_dereference(t->next);
1590                         }
1591                 }
1592         }
1593 }
1594
1595 static int __net_init ip6gre_init_net(struct net *net)
1596 {
1597         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1598         struct net_device *ndev;
1599         int err;
1600
1601         if (!net_has_fallback_tunnels(net))
1602                 return 0;
1603         ndev = alloc_netdev(sizeof(struct ip6_tnl), "ip6gre0",
1604                             NET_NAME_UNKNOWN, ip6gre_tunnel_setup);
1605         if (!ndev) {
1606                 err = -ENOMEM;
1607                 goto err_alloc_dev;
1608         }
1609         ign->fb_tunnel_dev = ndev;
1610         dev_net_set(ign->fb_tunnel_dev, net);
1611         /* FB netdevice is special: we have one, and only one per netns.
1612          * Allowing to move it to another netns is clearly unsafe.
1613          */
1614         ign->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL;
1615
1616
1617         ip6gre_fb_tunnel_init(ign->fb_tunnel_dev);
1618         ign->fb_tunnel_dev->rtnl_link_ops = &ip6gre_link_ops;
1619
1620         err = register_netdev(ign->fb_tunnel_dev);
1621         if (err)
1622                 goto err_reg_dev;
1623
1624         rcu_assign_pointer(ign->tunnels_wc[0],
1625                            netdev_priv(ign->fb_tunnel_dev));
1626         return 0;
1627
1628 err_reg_dev:
1629         free_netdev(ndev);
1630 err_alloc_dev:
1631         return err;
1632 }
1633
1634 static void __net_exit ip6gre_exit_batch_net(struct list_head *net_list)
1635 {
1636         struct net *net;
1637         LIST_HEAD(list);
1638
1639         rtnl_lock();
1640         list_for_each_entry(net, net_list, exit_list)
1641                 ip6gre_destroy_tunnels(net, &list);
1642         unregister_netdevice_many(&list);
1643         rtnl_unlock();
1644 }
1645
1646 static struct pernet_operations ip6gre_net_ops = {
1647         .init = ip6gre_init_net,
1648         .exit_batch = ip6gre_exit_batch_net,
1649         .id   = &ip6gre_net_id,
1650         .size = sizeof(struct ip6gre_net),
1651 };
1652
1653 static int ip6gre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[],
1654                                   struct netlink_ext_ack *extack)
1655 {
1656         __be16 flags;
1657
1658         if (!data)
1659                 return 0;
1660
1661         flags = 0;
1662         if (data[IFLA_GRE_IFLAGS])
1663                 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
1664         if (data[IFLA_GRE_OFLAGS])
1665                 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
1666         if (flags & (GRE_VERSION|GRE_ROUTING))
1667                 return -EINVAL;
1668
1669         return 0;
1670 }
1671
1672 static int ip6gre_tap_validate(struct nlattr *tb[], struct nlattr *data[],
1673                                struct netlink_ext_ack *extack)
1674 {
1675         struct in6_addr daddr;
1676
1677         if (tb[IFLA_ADDRESS]) {
1678                 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
1679                         return -EINVAL;
1680                 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
1681                         return -EADDRNOTAVAIL;
1682         }
1683
1684         if (!data)
1685                 goto out;
1686
1687         if (data[IFLA_GRE_REMOTE]) {
1688                 daddr = nla_get_in6_addr(data[IFLA_GRE_REMOTE]);
1689                 if (ipv6_addr_any(&daddr))
1690                         return -EINVAL;
1691         }
1692
1693 out:
1694         return ip6gre_tunnel_validate(tb, data, extack);
1695 }
1696
1697 static int ip6erspan_tap_validate(struct nlattr *tb[], struct nlattr *data[],
1698                                   struct netlink_ext_ack *extack)
1699 {
1700         __be16 flags = 0;
1701         int ret, ver = 0;
1702
1703         if (!data)
1704                 return 0;
1705
1706         ret = ip6gre_tap_validate(tb, data, extack);
1707         if (ret)
1708                 return ret;
1709
1710         /* ERSPAN should only have GRE sequence and key flag */
1711         if (data[IFLA_GRE_OFLAGS])
1712                 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
1713         if (data[IFLA_GRE_IFLAGS])
1714                 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
1715         if (!data[IFLA_GRE_COLLECT_METADATA] &&
1716             flags != (GRE_SEQ | GRE_KEY))
1717                 return -EINVAL;
1718
1719         /* ERSPAN Session ID only has 10-bit. Since we reuse
1720          * 32-bit key field as ID, check it's range.
1721          */
1722         if (data[IFLA_GRE_IKEY] &&
1723             (ntohl(nla_get_be32(data[IFLA_GRE_IKEY])) & ~ID_MASK))
1724                 return -EINVAL;
1725
1726         if (data[IFLA_GRE_OKEY] &&
1727             (ntohl(nla_get_be32(data[IFLA_GRE_OKEY])) & ~ID_MASK))
1728                 return -EINVAL;
1729
1730         if (data[IFLA_GRE_ERSPAN_VER]) {
1731                 ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]);
1732                 if (ver != 1 && ver != 2)
1733                         return -EINVAL;
1734         }
1735
1736         if (ver == 1) {
1737                 if (data[IFLA_GRE_ERSPAN_INDEX]) {
1738                         u32 index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]);
1739
1740                         if (index & ~INDEX_MASK)
1741                                 return -EINVAL;
1742                 }
1743         } else if (ver == 2) {
1744                 if (data[IFLA_GRE_ERSPAN_DIR]) {
1745                         u16 dir = nla_get_u8(data[IFLA_GRE_ERSPAN_DIR]);
1746
1747                         if (dir & ~(DIR_MASK >> DIR_OFFSET))
1748                                 return -EINVAL;
1749                 }
1750
1751                 if (data[IFLA_GRE_ERSPAN_HWID]) {
1752                         u16 hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]);
1753
1754                         if (hwid & ~(HWID_MASK >> HWID_OFFSET))
1755                                 return -EINVAL;
1756                 }
1757         }
1758
1759         return 0;
1760 }
1761
1762 static void ip6erspan_set_version(struct nlattr *data[],
1763                                   struct __ip6_tnl_parm *parms)
1764 {
1765         if (!data)
1766                 return;
1767
1768         parms->erspan_ver = 1;
1769         if (data[IFLA_GRE_ERSPAN_VER])
1770                 parms->erspan_ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]);
1771
1772         if (parms->erspan_ver == 1) {
1773                 if (data[IFLA_GRE_ERSPAN_INDEX])
1774                         parms->index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]);
1775         } else if (parms->erspan_ver == 2) {
1776                 if (data[IFLA_GRE_ERSPAN_DIR])
1777                         parms->dir = nla_get_u8(data[IFLA_GRE_ERSPAN_DIR]);
1778                 if (data[IFLA_GRE_ERSPAN_HWID])
1779                         parms->hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]);
1780         }
1781 }
1782
1783 static void ip6gre_netlink_parms(struct nlattr *data[],
1784                                 struct __ip6_tnl_parm *parms)
1785 {
1786         memset(parms, 0, sizeof(*parms));
1787
1788         if (!data)
1789                 return;
1790
1791         if (data[IFLA_GRE_LINK])
1792                 parms->link = nla_get_u32(data[IFLA_GRE_LINK]);
1793
1794         if (data[IFLA_GRE_IFLAGS])
1795                 parms->i_flags = gre_flags_to_tnl_flags(
1796                                 nla_get_be16(data[IFLA_GRE_IFLAGS]));
1797
1798         if (data[IFLA_GRE_OFLAGS])
1799                 parms->o_flags = gre_flags_to_tnl_flags(
1800                                 nla_get_be16(data[IFLA_GRE_OFLAGS]));
1801
1802         if (data[IFLA_GRE_IKEY])
1803                 parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]);
1804
1805         if (data[IFLA_GRE_OKEY])
1806                 parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]);
1807
1808         if (data[IFLA_GRE_LOCAL])
1809                 parms->laddr = nla_get_in6_addr(data[IFLA_GRE_LOCAL]);
1810
1811         if (data[IFLA_GRE_REMOTE])
1812                 parms->raddr = nla_get_in6_addr(data[IFLA_GRE_REMOTE]);
1813
1814         if (data[IFLA_GRE_TTL])
1815                 parms->hop_limit = nla_get_u8(data[IFLA_GRE_TTL]);
1816
1817         if (data[IFLA_GRE_ENCAP_LIMIT])
1818                 parms->encap_limit = nla_get_u8(data[IFLA_GRE_ENCAP_LIMIT]);
1819
1820         if (data[IFLA_GRE_FLOWINFO])
1821                 parms->flowinfo = nla_get_be32(data[IFLA_GRE_FLOWINFO]);
1822
1823         if (data[IFLA_GRE_FLAGS])
1824                 parms->flags = nla_get_u32(data[IFLA_GRE_FLAGS]);
1825
1826         if (data[IFLA_GRE_FWMARK])
1827                 parms->fwmark = nla_get_u32(data[IFLA_GRE_FWMARK]);
1828
1829         if (data[IFLA_GRE_COLLECT_METADATA])
1830                 parms->collect_md = true;
1831 }
1832
1833 static int ip6gre_tap_init(struct net_device *dev)
1834 {
1835         int ret;
1836
1837         ret = ip6gre_tunnel_init_common(dev);
1838         if (ret)
1839                 return ret;
1840
1841         dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1842
1843         return 0;
1844 }
1845
1846 static const struct net_device_ops ip6gre_tap_netdev_ops = {
1847         .ndo_init = ip6gre_tap_init,
1848         .ndo_uninit = ip6gre_tunnel_uninit,
1849         .ndo_start_xmit = ip6gre_tunnel_xmit,
1850         .ndo_set_mac_address = eth_mac_addr,
1851         .ndo_validate_addr = eth_validate_addr,
1852         .ndo_change_mtu = ip6_tnl_change_mtu,
1853         .ndo_get_stats64 = ip_tunnel_get_stats64,
1854         .ndo_get_iflink = ip6_tnl_get_iflink,
1855 };
1856
1857 static int ip6erspan_calc_hlen(struct ip6_tnl *tunnel)
1858 {
1859         int t_hlen;
1860
1861         tunnel->tun_hlen = 8;
1862         tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen +
1863                        erspan_hdr_len(tunnel->parms.erspan_ver);
1864
1865         t_hlen = tunnel->hlen + sizeof(struct ipv6hdr);
1866         tunnel->dev->needed_headroom = LL_MAX_HEADER + t_hlen;
1867         return t_hlen;
1868 }
1869
1870 static int ip6erspan_tap_init(struct net_device *dev)
1871 {
1872         struct ip6_tnl *tunnel;
1873         int t_hlen;
1874         int ret;
1875
1876         tunnel = netdev_priv(dev);
1877
1878         tunnel->dev = dev;
1879         tunnel->net = dev_net(dev);
1880         strcpy(tunnel->parms.name, dev->name);
1881
1882         dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1883         if (!dev->tstats)
1884                 return -ENOMEM;
1885
1886         ret = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
1887         if (ret)
1888                 goto cleanup_alloc_pcpu_stats;
1889
1890         ret = gro_cells_init(&tunnel->gro_cells, dev);
1891         if (ret)
1892                 goto cleanup_dst_cache_init;
1893
1894         t_hlen = ip6erspan_calc_hlen(tunnel);
1895         dev->mtu = ETH_DATA_LEN - t_hlen;
1896         if (dev->type == ARPHRD_ETHER)
1897                 dev->mtu -= ETH_HLEN;
1898         if (!(tunnel->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1899                 dev->mtu -= 8;
1900
1901         dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1902         ip6erspan_tnl_link_config(tunnel, 1);
1903
1904         dev_hold(dev);
1905         return 0;
1906
1907 cleanup_dst_cache_init:
1908         dst_cache_destroy(&tunnel->dst_cache);
1909 cleanup_alloc_pcpu_stats:
1910         free_percpu(dev->tstats);
1911         dev->tstats = NULL;
1912         return ret;
1913 }
1914
1915 static const struct net_device_ops ip6erspan_netdev_ops = {
1916         .ndo_init =             ip6erspan_tap_init,
1917         .ndo_uninit =           ip6erspan_tunnel_uninit,
1918         .ndo_start_xmit =       ip6erspan_tunnel_xmit,
1919         .ndo_set_mac_address =  eth_mac_addr,
1920         .ndo_validate_addr =    eth_validate_addr,
1921         .ndo_change_mtu =       ip6_tnl_change_mtu,
1922         .ndo_get_stats64 =      ip_tunnel_get_stats64,
1923         .ndo_get_iflink =       ip6_tnl_get_iflink,
1924 };
1925
1926 static void ip6gre_tap_setup(struct net_device *dev)
1927 {
1928
1929         ether_setup(dev);
1930
1931         dev->max_mtu = 0;
1932         dev->netdev_ops = &ip6gre_tap_netdev_ops;
1933         dev->needs_free_netdev = true;
1934         dev->priv_destructor = ip6gre_dev_free;
1935
1936         dev->priv_flags &= ~IFF_TX_SKB_SHARING;
1937         dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1938         netif_keep_dst(dev);
1939 }
1940
1941 static bool ip6gre_netlink_encap_parms(struct nlattr *data[],
1942                                        struct ip_tunnel_encap *ipencap)
1943 {
1944         bool ret = false;
1945
1946         memset(ipencap, 0, sizeof(*ipencap));
1947
1948         if (!data)
1949                 return ret;
1950
1951         if (data[IFLA_GRE_ENCAP_TYPE]) {
1952                 ret = true;
1953                 ipencap->type = nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]);
1954         }
1955
1956         if (data[IFLA_GRE_ENCAP_FLAGS]) {
1957                 ret = true;
1958                 ipencap->flags = nla_get_u16(data[IFLA_GRE_ENCAP_FLAGS]);
1959         }
1960
1961         if (data[IFLA_GRE_ENCAP_SPORT]) {
1962                 ret = true;
1963                 ipencap->sport = nla_get_be16(data[IFLA_GRE_ENCAP_SPORT]);
1964         }
1965
1966         if (data[IFLA_GRE_ENCAP_DPORT]) {
1967                 ret = true;
1968                 ipencap->dport = nla_get_be16(data[IFLA_GRE_ENCAP_DPORT]);
1969         }
1970
1971         return ret;
1972 }
1973
1974 static int ip6gre_newlink_common(struct net *src_net, struct net_device *dev,
1975                                  struct nlattr *tb[], struct nlattr *data[],
1976                                  struct netlink_ext_ack *extack)
1977 {
1978         struct ip6_tnl *nt;
1979         struct ip_tunnel_encap ipencap;
1980         int err;
1981
1982         nt = netdev_priv(dev);
1983
1984         if (ip6gre_netlink_encap_parms(data, &ipencap)) {
1985                 int err = ip6_tnl_encap_setup(nt, &ipencap);
1986
1987                 if (err < 0)
1988                         return err;
1989         }
1990
1991         if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS])
1992                 eth_hw_addr_random(dev);
1993
1994         nt->dev = dev;
1995         nt->net = dev_net(dev);
1996
1997         err = register_netdevice(dev);
1998         if (err)
1999                 goto out;
2000
2001         if (tb[IFLA_MTU])
2002                 ip6_tnl_change_mtu(dev, nla_get_u32(tb[IFLA_MTU]));
2003
2004 out:
2005         return err;
2006 }
2007
2008 static int ip6gre_newlink(struct net *src_net, struct net_device *dev,
2009                           struct nlattr *tb[], struct nlattr *data[],
2010                           struct netlink_ext_ack *extack)
2011 {
2012         struct ip6_tnl *nt = netdev_priv(dev);
2013         struct net *net = dev_net(dev);
2014         struct ip6gre_net *ign;
2015         int err;
2016
2017         ip6gre_netlink_parms(data, &nt->parms);
2018         ign = net_generic(net, ip6gre_net_id);
2019
2020         if (nt->parms.collect_md) {
2021                 if (rtnl_dereference(ign->collect_md_tun))
2022                         return -EEXIST;
2023         } else {
2024                 if (ip6gre_tunnel_find(net, &nt->parms, dev->type))
2025                         return -EEXIST;
2026         }
2027
2028         err = ip6gre_newlink_common(src_net, dev, tb, data, extack);
2029         if (!err) {
2030                 ip6gre_tnl_link_config(nt, !tb[IFLA_MTU]);
2031                 ip6gre_tunnel_link_md(ign, nt);
2032                 ip6gre_tunnel_link(net_generic(net, ip6gre_net_id), nt);
2033         }
2034         return err;
2035 }
2036
2037 static struct ip6_tnl *
2038 ip6gre_changelink_common(struct net_device *dev, struct nlattr *tb[],
2039                          struct nlattr *data[], struct __ip6_tnl_parm *p_p,
2040                          struct netlink_ext_ack *extack)
2041 {
2042         struct ip6_tnl *t, *nt = netdev_priv(dev);
2043         struct net *net = nt->net;
2044         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
2045         struct ip_tunnel_encap ipencap;
2046
2047         if (dev == ign->fb_tunnel_dev)
2048                 return ERR_PTR(-EINVAL);
2049
2050         if (ip6gre_netlink_encap_parms(data, &ipencap)) {
2051                 int err = ip6_tnl_encap_setup(nt, &ipencap);
2052
2053                 if (err < 0)
2054                         return ERR_PTR(err);
2055         }
2056
2057         ip6gre_netlink_parms(data, p_p);
2058
2059         t = ip6gre_tunnel_locate(net, p_p, 0);
2060
2061         if (t) {
2062                 if (t->dev != dev)
2063                         return ERR_PTR(-EEXIST);
2064         } else {
2065                 t = nt;
2066         }
2067
2068         return t;
2069 }
2070
2071 static int ip6gre_changelink(struct net_device *dev, struct nlattr *tb[],
2072                              struct nlattr *data[],
2073                              struct netlink_ext_ack *extack)
2074 {
2075         struct ip6_tnl *t = netdev_priv(dev);
2076         struct ip6gre_net *ign = net_generic(t->net, ip6gre_net_id);
2077         struct __ip6_tnl_parm p;
2078
2079         t = ip6gre_changelink_common(dev, tb, data, &p, extack);
2080         if (IS_ERR(t))
2081                 return PTR_ERR(t);
2082
2083         ip6gre_tunnel_unlink_md(ign, t);
2084         ip6gre_tunnel_unlink(ign, t);
2085         ip6gre_tnl_change(t, &p, !tb[IFLA_MTU]);
2086         ip6gre_tunnel_link_md(ign, t);
2087         ip6gre_tunnel_link(ign, t);
2088         return 0;
2089 }
2090
2091 static void ip6gre_dellink(struct net_device *dev, struct list_head *head)
2092 {
2093         struct net *net = dev_net(dev);
2094         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
2095
2096         if (dev != ign->fb_tunnel_dev)
2097                 unregister_netdevice_queue(dev, head);
2098 }
2099
2100 static size_t ip6gre_get_size(const struct net_device *dev)
2101 {
2102         return
2103                 /* IFLA_GRE_LINK */
2104                 nla_total_size(4) +
2105                 /* IFLA_GRE_IFLAGS */
2106                 nla_total_size(2) +
2107                 /* IFLA_GRE_OFLAGS */
2108                 nla_total_size(2) +
2109                 /* IFLA_GRE_IKEY */
2110                 nla_total_size(4) +
2111                 /* IFLA_GRE_OKEY */
2112                 nla_total_size(4) +
2113                 /* IFLA_GRE_LOCAL */
2114                 nla_total_size(sizeof(struct in6_addr)) +
2115                 /* IFLA_GRE_REMOTE */
2116                 nla_total_size(sizeof(struct in6_addr)) +
2117                 /* IFLA_GRE_TTL */
2118                 nla_total_size(1) +
2119                 /* IFLA_GRE_ENCAP_LIMIT */
2120                 nla_total_size(1) +
2121                 /* IFLA_GRE_FLOWINFO */
2122                 nla_total_size(4) +
2123                 /* IFLA_GRE_FLAGS */
2124                 nla_total_size(4) +
2125                 /* IFLA_GRE_ENCAP_TYPE */
2126                 nla_total_size(2) +
2127                 /* IFLA_GRE_ENCAP_FLAGS */
2128                 nla_total_size(2) +
2129                 /* IFLA_GRE_ENCAP_SPORT */
2130                 nla_total_size(2) +
2131                 /* IFLA_GRE_ENCAP_DPORT */
2132                 nla_total_size(2) +
2133                 /* IFLA_GRE_COLLECT_METADATA */
2134                 nla_total_size(0) +
2135                 /* IFLA_GRE_FWMARK */
2136                 nla_total_size(4) +
2137                 /* IFLA_GRE_ERSPAN_INDEX */
2138                 nla_total_size(4) +
2139                 0;
2140 }
2141
2142 static int ip6gre_fill_info(struct sk_buff *skb, const struct net_device *dev)
2143 {
2144         struct ip6_tnl *t = netdev_priv(dev);
2145         struct __ip6_tnl_parm *p = &t->parms;
2146         __be16 o_flags = p->o_flags;
2147
2148         if (p->erspan_ver == 1 || p->erspan_ver == 2) {
2149                 if (!p->collect_md)
2150                         o_flags |= TUNNEL_KEY;
2151
2152                 if (nla_put_u8(skb, IFLA_GRE_ERSPAN_VER, p->erspan_ver))
2153                         goto nla_put_failure;
2154
2155                 if (p->erspan_ver == 1) {
2156                         if (nla_put_u32(skb, IFLA_GRE_ERSPAN_INDEX, p->index))
2157                                 goto nla_put_failure;
2158                 } else {
2159                         if (nla_put_u8(skb, IFLA_GRE_ERSPAN_DIR, p->dir))
2160                                 goto nla_put_failure;
2161                         if (nla_put_u16(skb, IFLA_GRE_ERSPAN_HWID, p->hwid))
2162                                 goto nla_put_failure;
2163                 }
2164         }
2165
2166         if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) ||
2167             nla_put_be16(skb, IFLA_GRE_IFLAGS,
2168                          gre_tnl_flags_to_gre_flags(p->i_flags)) ||
2169             nla_put_be16(skb, IFLA_GRE_OFLAGS,
2170                          gre_tnl_flags_to_gre_flags(o_flags)) ||
2171             nla_put_be32(skb, IFLA_GRE_IKEY, p->i_key) ||
2172             nla_put_be32(skb, IFLA_GRE_OKEY, p->o_key) ||
2173             nla_put_in6_addr(skb, IFLA_GRE_LOCAL, &p->laddr) ||
2174             nla_put_in6_addr(skb, IFLA_GRE_REMOTE, &p->raddr) ||
2175             nla_put_u8(skb, IFLA_GRE_TTL, p->hop_limit) ||
2176             nla_put_u8(skb, IFLA_GRE_ENCAP_LIMIT, p->encap_limit) ||
2177             nla_put_be32(skb, IFLA_GRE_FLOWINFO, p->flowinfo) ||
2178             nla_put_u32(skb, IFLA_GRE_FLAGS, p->flags) ||
2179             nla_put_u32(skb, IFLA_GRE_FWMARK, p->fwmark))
2180                 goto nla_put_failure;
2181
2182         if (nla_put_u16(skb, IFLA_GRE_ENCAP_TYPE,
2183                         t->encap.type) ||
2184             nla_put_be16(skb, IFLA_GRE_ENCAP_SPORT,
2185                          t->encap.sport) ||
2186             nla_put_be16(skb, IFLA_GRE_ENCAP_DPORT,
2187                          t->encap.dport) ||
2188             nla_put_u16(skb, IFLA_GRE_ENCAP_FLAGS,
2189                         t->encap.flags))
2190                 goto nla_put_failure;
2191
2192         if (p->collect_md) {
2193                 if (nla_put_flag(skb, IFLA_GRE_COLLECT_METADATA))
2194                         goto nla_put_failure;
2195         }
2196
2197         return 0;
2198
2199 nla_put_failure:
2200         return -EMSGSIZE;
2201 }
2202
2203 static const struct nla_policy ip6gre_policy[IFLA_GRE_MAX + 1] = {
2204         [IFLA_GRE_LINK]        = { .type = NLA_U32 },
2205         [IFLA_GRE_IFLAGS]      = { .type = NLA_U16 },
2206         [IFLA_GRE_OFLAGS]      = { .type = NLA_U16 },
2207         [IFLA_GRE_IKEY]        = { .type = NLA_U32 },
2208         [IFLA_GRE_OKEY]        = { .type = NLA_U32 },
2209         [IFLA_GRE_LOCAL]       = { .len = sizeof_field(struct ipv6hdr, saddr) },
2210         [IFLA_GRE_REMOTE]      = { .len = sizeof_field(struct ipv6hdr, daddr) },
2211         [IFLA_GRE_TTL]         = { .type = NLA_U8 },
2212         [IFLA_GRE_ENCAP_LIMIT] = { .type = NLA_U8 },
2213         [IFLA_GRE_FLOWINFO]    = { .type = NLA_U32 },
2214         [IFLA_GRE_FLAGS]       = { .type = NLA_U32 },
2215         [IFLA_GRE_ENCAP_TYPE]   = { .type = NLA_U16 },
2216         [IFLA_GRE_ENCAP_FLAGS]  = { .type = NLA_U16 },
2217         [IFLA_GRE_ENCAP_SPORT]  = { .type = NLA_U16 },
2218         [IFLA_GRE_ENCAP_DPORT]  = { .type = NLA_U16 },
2219         [IFLA_GRE_COLLECT_METADATA] = { .type = NLA_FLAG },
2220         [IFLA_GRE_FWMARK]       = { .type = NLA_U32 },
2221         [IFLA_GRE_ERSPAN_INDEX] = { .type = NLA_U32 },
2222         [IFLA_GRE_ERSPAN_VER]   = { .type = NLA_U8 },
2223         [IFLA_GRE_ERSPAN_DIR]   = { .type = NLA_U8 },
2224         [IFLA_GRE_ERSPAN_HWID]  = { .type = NLA_U16 },
2225 };
2226
2227 static void ip6erspan_tap_setup(struct net_device *dev)
2228 {
2229         ether_setup(dev);
2230
2231         dev->max_mtu = 0;
2232         dev->netdev_ops = &ip6erspan_netdev_ops;
2233         dev->needs_free_netdev = true;
2234         dev->priv_destructor = ip6gre_dev_free;
2235
2236         dev->priv_flags &= ~IFF_TX_SKB_SHARING;
2237         dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
2238         netif_keep_dst(dev);
2239 }
2240
2241 static int ip6erspan_newlink(struct net *src_net, struct net_device *dev,
2242                              struct nlattr *tb[], struct nlattr *data[],
2243                              struct netlink_ext_ack *extack)
2244 {
2245         struct ip6_tnl *nt = netdev_priv(dev);
2246         struct net *net = dev_net(dev);
2247         struct ip6gre_net *ign;
2248         int err;
2249
2250         ip6gre_netlink_parms(data, &nt->parms);
2251         ip6erspan_set_version(data, &nt->parms);
2252         ign = net_generic(net, ip6gre_net_id);
2253
2254         if (nt->parms.collect_md) {
2255                 if (rtnl_dereference(ign->collect_md_tun_erspan))
2256                         return -EEXIST;
2257         } else {
2258                 if (ip6gre_tunnel_find(net, &nt->parms, dev->type))
2259                         return -EEXIST;
2260         }
2261
2262         err = ip6gre_newlink_common(src_net, dev, tb, data, extack);
2263         if (!err) {
2264                 ip6erspan_tnl_link_config(nt, !tb[IFLA_MTU]);
2265                 ip6erspan_tunnel_link_md(ign, nt);
2266                 ip6gre_tunnel_link(net_generic(net, ip6gre_net_id), nt);
2267         }
2268         return err;
2269 }
2270
2271 static void ip6erspan_tnl_link_config(struct ip6_tnl *t, int set_mtu)
2272 {
2273         ip6gre_tnl_link_config_common(t);
2274         ip6gre_tnl_link_config_route(t, set_mtu, ip6erspan_calc_hlen(t));
2275 }
2276
2277 static int ip6erspan_tnl_change(struct ip6_tnl *t,
2278                                 const struct __ip6_tnl_parm *p, int set_mtu)
2279 {
2280         ip6gre_tnl_copy_tnl_parm(t, p);
2281         ip6erspan_tnl_link_config(t, set_mtu);
2282         return 0;
2283 }
2284
2285 static int ip6erspan_changelink(struct net_device *dev, struct nlattr *tb[],
2286                                 struct nlattr *data[],
2287                                 struct netlink_ext_ack *extack)
2288 {
2289         struct ip6gre_net *ign = net_generic(dev_net(dev), ip6gre_net_id);
2290         struct __ip6_tnl_parm p;
2291         struct ip6_tnl *t;
2292
2293         t = ip6gre_changelink_common(dev, tb, data, &p, extack);
2294         if (IS_ERR(t))
2295                 return PTR_ERR(t);
2296
2297         ip6erspan_set_version(data, &p);
2298         ip6gre_tunnel_unlink_md(ign, t);
2299         ip6gre_tunnel_unlink(ign, t);
2300         ip6erspan_tnl_change(t, &p, !tb[IFLA_MTU]);
2301         ip6erspan_tunnel_link_md(ign, t);
2302         ip6gre_tunnel_link(ign, t);
2303         return 0;
2304 }
2305
2306 static struct rtnl_link_ops ip6gre_link_ops __read_mostly = {
2307         .kind           = "ip6gre",
2308         .maxtype        = IFLA_GRE_MAX,
2309         .policy         = ip6gre_policy,
2310         .priv_size      = sizeof(struct ip6_tnl),
2311         .setup          = ip6gre_tunnel_setup,
2312         .validate       = ip6gre_tunnel_validate,
2313         .newlink        = ip6gre_newlink,
2314         .changelink     = ip6gre_changelink,
2315         .dellink        = ip6gre_dellink,
2316         .get_size       = ip6gre_get_size,
2317         .fill_info      = ip6gre_fill_info,
2318         .get_link_net   = ip6_tnl_get_link_net,
2319 };
2320
2321 static struct rtnl_link_ops ip6gre_tap_ops __read_mostly = {
2322         .kind           = "ip6gretap",
2323         .maxtype        = IFLA_GRE_MAX,
2324         .policy         = ip6gre_policy,
2325         .priv_size      = sizeof(struct ip6_tnl),
2326         .setup          = ip6gre_tap_setup,
2327         .validate       = ip6gre_tap_validate,
2328         .newlink        = ip6gre_newlink,
2329         .changelink     = ip6gre_changelink,
2330         .get_size       = ip6gre_get_size,
2331         .fill_info      = ip6gre_fill_info,
2332         .get_link_net   = ip6_tnl_get_link_net,
2333 };
2334
2335 static struct rtnl_link_ops ip6erspan_tap_ops __read_mostly = {
2336         .kind           = "ip6erspan",
2337         .maxtype        = IFLA_GRE_MAX,
2338         .policy         = ip6gre_policy,
2339         .priv_size      = sizeof(struct ip6_tnl),
2340         .setup          = ip6erspan_tap_setup,
2341         .validate       = ip6erspan_tap_validate,
2342         .newlink        = ip6erspan_newlink,
2343         .changelink     = ip6erspan_changelink,
2344         .get_size       = ip6gre_get_size,
2345         .fill_info      = ip6gre_fill_info,
2346         .get_link_net   = ip6_tnl_get_link_net,
2347 };
2348
2349 /*
2350  *      And now the modules code and kernel interface.
2351  */
2352
2353 static int __init ip6gre_init(void)
2354 {
2355         int err;
2356
2357         pr_info("GRE over IPv6 tunneling driver\n");
2358
2359         err = register_pernet_device(&ip6gre_net_ops);
2360         if (err < 0)
2361                 return err;
2362
2363         err = inet6_add_protocol(&ip6gre_protocol, IPPROTO_GRE);
2364         if (err < 0) {
2365                 pr_info("%s: can't add protocol\n", __func__);
2366                 goto add_proto_failed;
2367         }
2368
2369         err = rtnl_link_register(&ip6gre_link_ops);
2370         if (err < 0)
2371                 goto rtnl_link_failed;
2372
2373         err = rtnl_link_register(&ip6gre_tap_ops);
2374         if (err < 0)
2375                 goto tap_ops_failed;
2376
2377         err = rtnl_link_register(&ip6erspan_tap_ops);
2378         if (err < 0)
2379                 goto erspan_link_failed;
2380
2381 out:
2382         return err;
2383
2384 erspan_link_failed:
2385         rtnl_link_unregister(&ip6gre_tap_ops);
2386 tap_ops_failed:
2387         rtnl_link_unregister(&ip6gre_link_ops);
2388 rtnl_link_failed:
2389         inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE);
2390 add_proto_failed:
2391         unregister_pernet_device(&ip6gre_net_ops);
2392         goto out;
2393 }
2394
2395 static void __exit ip6gre_fini(void)
2396 {
2397         rtnl_link_unregister(&ip6gre_tap_ops);
2398         rtnl_link_unregister(&ip6gre_link_ops);
2399         rtnl_link_unregister(&ip6erspan_tap_ops);
2400         inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE);
2401         unregister_pernet_device(&ip6gre_net_ops);
2402 }
2403
2404 module_init(ip6gre_init);
2405 module_exit(ip6gre_fini);
2406 MODULE_LICENSE("GPL");
2407 MODULE_AUTHOR("D. Kozlov (xeb@mail.ru)");
2408 MODULE_DESCRIPTION("GRE over IPv6 tunneling device");
2409 MODULE_ALIAS_RTNL_LINK("ip6gre");
2410 MODULE_ALIAS_RTNL_LINK("ip6gretap");
2411 MODULE_ALIAS_RTNL_LINK("ip6erspan");
2412 MODULE_ALIAS_NETDEV("ip6gre0");