net/ipv6/ip6_gre.c

   1 /*
   2  *      GRE over IPv6 protocol decoder.
   3  *
   4  *      Authors: Dmitry Kozlov (xeb@mail.ru)
   5  *
   6  *      This program is free software; you can redistribute it and/or
   7  *      modify it under the terms of the GNU General Public License
   8  *      as published by the Free Software Foundation; either version
   9  *      2 of the License, or (at your option) any later version.
  10  *
  11  */
  12
  13 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  14
  15 #include <linux/capability.h>
  16 #include <linux/module.h>
  17 #include <linux/types.h>
  18 #include <linux/kernel.h>
  19 #include <linux/slab.h>
  20 #include <linux/uaccess.h>
  21 #include <linux/skbuff.h>
  22 #include <linux/netdevice.h>
  23 #include <linux/in.h>
  24 #include <linux/tcp.h>
  25 #include <linux/udp.h>
  26 #include <linux/if_arp.h>
  27 #include <linux/mroute.h>
  28 #include <linux/init.h>
  29 #include <linux/in6.h>
  30 #include <linux/inetdevice.h>
  31 #include <linux/igmp.h>
  32 #include <linux/netfilter_ipv4.h>
  33 #include <linux/etherdevice.h>
  34 #include <linux/if_ether.h>
  35 #include <linux/hash.h>
  36 #include <linux/if_tunnel.h>
  37 #include <linux/ip6_tunnel.h>
  38
  39 #include <net/sock.h>
  40 #include <net/ip.h>
  41 #include <net/ip_tunnels.h>
  42 #include <net/icmp.h>
  43 #include <net/protocol.h>
  44 #include <net/addrconf.h>
  45 #include <net/arp.h>
  46 #include <net/checksum.h>
  47 #include <net/dsfield.h>
  48 #include <net/inet_ecn.h>
  49 #include <net/xfrm.h>
  50 #include <net/net_namespace.h>
  51 #include <net/netns/generic.h>
  52 #include <net/rtnetlink.h>
  53
  54 #include <net/ipv6.h>
  55 #include <net/ip6_fib.h>
  56 #include <net/ip6_route.h>
  57 #include <net/ip6_tunnel.h>
  58
  59
  60 static bool log_ecn_error = true;
  61 module_param(log_ecn_error, bool, 0644);
  62 MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");
  63
  64 #define IPV6_TCLASS_MASK (IPV6_FLOWINFO_MASK & ~IPV6_FLOWLABEL_MASK)
  65 #define IPV6_TCLASS_SHIFT 20
  66
  67 #define HASH_SIZE_SHIFT  5
  68 #define HASH_SIZE (1 << HASH_SIZE_SHIFT)
  69
  70 static int ip6gre_net_id __read_mostly;
  71 struct ip6gre_net {
  72         struct ip6_tnl __rcu *tunnels[4][HASH_SIZE];
  73
  74         struct net_device *fb_tunnel_dev;
  75 };
  76
  77 static struct rtnl_link_ops ip6gre_link_ops __read_mostly;
  78 static int ip6gre_tunnel_init(struct net_device *dev);
  79 static void ip6gre_tunnel_setup(struct net_device *dev);
  80 static void ip6gre_tunnel_link(struct ip6gre_net *ign, struct ip6_tnl *t);
  81 static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu);
  82
  83 /* Tunnel hash table */
  84
  85 /*
  86    4 hash tables:
  87
  88    3: (remote,local)
  89    2: (remote,*)
  90    1: (*,local)
  91    0: (*,*)
  92
  93    We require exact key match i.e. if a key is present in packet
  94    it will match only tunnel with the same key; if it is not present,
  95    it will match only keyless tunnel.
  96
  97    All keysless packets, if not matched configured keyless tunnels
  98    will match fallback tunnel.
  99  */
 100
 101 #define HASH_KEY(key) (((__force u32)key^((__force u32)key>>4))&(HASH_SIZE - 1))
 102 static u32 HASH_ADDR(const struct in6_addr *addr)
 103 {
 104         u32 hash = ipv6_addr_hash(addr);
 105
 106         return hash_32(hash, HASH_SIZE_SHIFT);
 107 }
 108
 109 #define tunnels_r_l     tunnels[3]
 110 #define tunnels_r       tunnels[2]
 111 #define tunnels_l       tunnels[1]
 112 #define tunnels_wc      tunnels[0]
 113
 114 /* Given src, dst and key, find appropriate for input tunnel. */
 115
 116 static struct ip6_tnl *ip6gre_tunnel_lookup(struct net_device *dev,
 117                 const struct in6_addr *remote, const struct in6_addr *local,
 118                 __be32 key, __be16 gre_proto)
 119 {
 120         struct net *net = dev_net(dev);
 121         int link = dev->ifindex;
 122         unsigned int h0 = HASH_ADDR(remote);
 123         unsigned int h1 = HASH_KEY(key);
 124         struct ip6_tnl *t, *cand = NULL;
 125         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
 126         int dev_type = (gre_proto == htons(ETH_P_TEB)) ?
 127                        ARPHRD_ETHER : ARPHRD_IP6GRE;
 128         int score, cand_score = 4;
 129
 130         for_each_ip_tunnel_rcu(t, ign->tunnels_r_l[h0 ^ h1]) {
 131                 if (!ipv6_addr_equal(local, &t->parms.laddr) ||
 132                     !ipv6_addr_equal(remote, &t->parms.raddr) ||
 133                     key != t->parms.i_key ||
 134                     !(t->dev->flags & IFF_UP))
 135                         continue;
 136
 137                 if (t->dev->type != ARPHRD_IP6GRE &&
 138                     t->dev->type != dev_type)
 139                         continue;
 140
 141                 score = 0;
 142                 if (t->parms.link != link)
 143                         score |= 1;
 144                 if (t->dev->type != dev_type)
 145                         score |= 2;
 146                 if (score == 0)
 147                         return t;
 148
 149                 if (score < cand_score) {
 150                         cand = t;
 151                         cand_score = score;
 152                 }
 153         }
 154
 155         for_each_ip_tunnel_rcu(t, ign->tunnels_r[h0 ^ h1]) {
 156                 if (!ipv6_addr_equal(remote, &t->parms.raddr) ||
 157                     key != t->parms.i_key ||
 158                     !(t->dev->flags & IFF_UP))
 159                         continue;
 160
 161                 if (t->dev->type != ARPHRD_IP6GRE &&
 162                     t->dev->type != dev_type)
 163                         continue;
 164
 165                 score = 0;
 166                 if (t->parms.link != link)
 167                         score |= 1;
 168                 if (t->dev->type != dev_type)
 169                         score |= 2;
 170                 if (score == 0)
 171                         return t;
 172
 173                 if (score < cand_score) {
 174                         cand = t;
 175                         cand_score = score;
 176                 }
 177         }
 178
 179         for_each_ip_tunnel_rcu(t, ign->tunnels_l[h1]) {
 180                 if ((!ipv6_addr_equal(local, &t->parms.laddr) &&
 181                           (!ipv6_addr_equal(local, &t->parms.raddr) ||
 182                                  !ipv6_addr_is_multicast(local))) ||
 183                     key != t->parms.i_key ||
 184                     !(t->dev->flags & IFF_UP))
 185                         continue;
 186
 187                 if (t->dev->type != ARPHRD_IP6GRE &&
 188                     t->dev->type != dev_type)
 189                         continue;
 190
 191                 score = 0;
 192                 if (t->parms.link != link)
 193                         score |= 1;
 194                 if (t->dev->type != dev_type)
 195                         score |= 2;
 196                 if (score == 0)
 197                         return t;
 198
 199                 if (score < cand_score) {
 200                         cand = t;
 201                         cand_score = score;
 202                 }
 203         }
 204
 205         for_each_ip_tunnel_rcu(t, ign->tunnels_wc[h1]) {
 206                 if (t->parms.i_key != key ||
 207                     !(t->dev->flags & IFF_UP))
 208                         continue;
 209
 210                 if (t->dev->type != ARPHRD_IP6GRE &&
 211                     t->dev->type != dev_type)
 212                         continue;
 213
 214                 score = 0;
 215                 if (t->parms.link != link)
 216                         score |= 1;
 217                 if (t->dev->type != dev_type)
 218                         score |= 2;
 219                 if (score == 0)
 220                         return t;
 221
 222                 if (score < cand_score) {
 223                         cand = t;
 224                         cand_score = score;
 225                 }
 226         }
 227
 228         if (cand != NULL)
 229                 return cand;
 230
 231         dev = ign->fb_tunnel_dev;
 232         if (dev->flags & IFF_UP)
 233                 return netdev_priv(dev);
 234
 235         return NULL;
 236 }
 237
 238 static struct ip6_tnl __rcu **__ip6gre_bucket(struct ip6gre_net *ign,
 239                 const struct __ip6_tnl_parm *p)
 240 {
 241         const struct in6_addr *remote = &p->raddr;
 242         const struct in6_addr *local = &p->laddr;
 243         unsigned int h = HASH_KEY(p->i_key);
 244         int prio = 0;
 245
 246         if (!ipv6_addr_any(local))
 247                 prio |= 1;
 248         if (!ipv6_addr_any(remote) && !ipv6_addr_is_multicast(remote)) {
 249                 prio |= 2;
 250                 h ^= HASH_ADDR(remote);
 251         }
 252
 253         return &ign->tunnels[prio][h];
 254 }
 255
 256 static inline struct ip6_tnl __rcu **ip6gre_bucket(struct ip6gre_net *ign,
 257                 const struct ip6_tnl *t)
 258 {
 259         return __ip6gre_bucket(ign, &t->parms);
 260 }
 261
 262 static void ip6gre_tunnel_link(struct ip6gre_net *ign, struct ip6_tnl *t)
 263 {
 264         struct ip6_tnl __rcu **tp = ip6gre_bucket(ign, t);
 265
 266         rcu_assign_pointer(t->next, rtnl_dereference(*tp));
 267         rcu_assign_pointer(*tp, t);
 268 }
 269
 270 static void ip6gre_tunnel_unlink(struct ip6gre_net *ign, struct ip6_tnl *t)
 271 {
 272         struct ip6_tnl __rcu **tp;
 273         struct ip6_tnl *iter;
 274
 275         for (tp = ip6gre_bucket(ign, t);
 276              (iter = rtnl_dereference(*tp)) != NULL;
 277              tp = &iter->next) {
 278                 if (t == iter) {
 279                         rcu_assign_pointer(*tp, t->next);
 280                         break;
 281                 }
 282         }
 283 }
 284
 285 static struct ip6_tnl *ip6gre_tunnel_find(struct net *net,
 286                                            const struct __ip6_tnl_parm *parms,
 287                                            int type)
 288 {
 289         const struct in6_addr *remote = &parms->raddr;
 290         const struct in6_addr *local = &parms->laddr;
 291         __be32 key = parms->i_key;
 292         int link = parms->link;
 293         struct ip6_tnl *t;
 294         struct ip6_tnl __rcu **tp;
 295         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
 296
 297         for (tp = __ip6gre_bucket(ign, parms);
 298              (t = rtnl_dereference(*tp)) != NULL;
 299              tp = &t->next)
 300                 if (ipv6_addr_equal(local, &t->parms.laddr) &&
 301                     ipv6_addr_equal(remote, &t->parms.raddr) &&
 302                     key == t->parms.i_key &&
 303                     link == t->parms.link &&
 304                     type == t->dev->type)
 305                         break;
 306
 307         return t;
 308 }
 309
 310 static struct ip6_tnl *ip6gre_tunnel_locate(struct net *net,
 311                 const struct __ip6_tnl_parm *parms, int create)
 312 {
 313         struct ip6_tnl *t, *nt;
 314         struct net_device *dev;
 315         char name[IFNAMSIZ];
 316         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
 317
 318         t = ip6gre_tunnel_find(net, parms, ARPHRD_IP6GRE);
 319         if (t || !create)
 320                 return t;
 321
 322         if (parms->name[0])
 323                 strlcpy(name, parms->name, IFNAMSIZ);
 324         else
 325                 strcpy(name, "ip6gre%d");
 326
 327         dev = alloc_netdev(sizeof(*t), name, ip6gre_tunnel_setup);
 328         if (!dev)
 329                 return NULL;
 330
 331         dev_net_set(dev, net);
 332
 333         nt = netdev_priv(dev);
 334         nt->parms = *parms;
 335         dev->rtnl_link_ops = &ip6gre_link_ops;
 336
 337         nt->dev = dev;
 338         ip6gre_tnl_link_config(nt, 1);
 339
 340         if (register_netdevice(dev) < 0)
 341                 goto failed_free;
 342
 343         /* Can use a lockless transmit, unless we generate output sequences */
 344         if (!(nt->parms.o_flags & GRE_SEQ))
 345                 dev->features |= NETIF_F_LLTX;
 346
 347         dev_hold(dev);
 348         ip6gre_tunnel_link(ign, nt);
 349         return nt;
 350
 351 failed_free:
 352         free_netdev(dev);
 353         return NULL;
 354 }
 355
 356 static void ip6gre_tunnel_uninit(struct net_device *dev)
 357 {
 358         struct net *net = dev_net(dev);
 359         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
 360
 361         ip6gre_tunnel_unlink(ign, netdev_priv(dev));
 362         dev_put(dev);
 363 }
 364
 365
 366 static void ip6gre_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 367                 u8 type, u8 code, int offset, __be32 info)
 368 {
 369         const struct ipv6hdr *ipv6h = (const struct ipv6hdr *)skb->data;
 370         __be16 *p = (__be16 *)(skb->data + offset);
 371         int grehlen = offset + 4;
 372         struct ip6_tnl *t;
 373         __be16 flags;
 374
 375         flags = p[0];
 376         if (flags&(GRE_CSUM|GRE_KEY|GRE_SEQ|GRE_ROUTING|GRE_VERSION)) {
 377                 if (flags&(GRE_VERSION|GRE_ROUTING))
 378                         return;
 379                 if (flags&GRE_KEY) {
 380                         grehlen += 4;
 381                         if (flags&GRE_CSUM)
 382                                 grehlen += 4;
 383                 }
 384         }
 385
 386         /* If only 8 bytes returned, keyed message will be dropped here */
 387         if (!pskb_may_pull(skb, grehlen))
 388                 return;
 389         ipv6h = (const struct ipv6hdr *)skb->data;
 390         p = (__be16 *)(skb->data + offset);
 391
 392         t = ip6gre_tunnel_lookup(skb->dev, &ipv6h->daddr, &ipv6h->saddr,
 393                                 flags & GRE_KEY ?
 394                                 *(((__be32 *)p) + (grehlen / 4) - 1) : 0,
 395                                 p[1]);
 396         if (t == NULL)
 397                 return;
 398
 399         switch (type) {
 400                 __u32 teli;
 401                 struct ipv6_tlv_tnl_enc_lim *tel;
 402                 __u32 mtu;
 403         case ICMPV6_DEST_UNREACH:
 404                 net_warn_ratelimited("%s: Path to destination invalid or inactive!\n",
 405                                      t->parms.name);
 406                 break;
 407         case ICMPV6_TIME_EXCEED:
 408                 if (code == ICMPV6_EXC_HOPLIMIT) {
 409                         net_warn_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n",
 410                                              t->parms.name);
 411                 }
 412                 break;
 413         case ICMPV6_PARAMPROB:
 414                 teli = 0;
 415                 if (code == ICMPV6_HDR_FIELD)
 416                         teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data);
 417
 418                 if (teli && teli == info - 2) {
 419                         tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli];
 420                         if (tel->encap_limit == 0) {
 421                                 net_warn_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n",
 422                                                      t->parms.name);
 423                         }
 424                 } else {
 425                         net_warn_ratelimited("%s: Recipient unable to parse tunneled packet!\n",
 426                                              t->parms.name);
 427                 }
 428                 break;
 429         case ICMPV6_PKT_TOOBIG:
 430                 mtu = info - offset;
 431                 if (mtu < IPV6_MIN_MTU)
 432                         mtu = IPV6_MIN_MTU;
 433                 t->dev->mtu = mtu;
 434                 break;
 435         }
 436
 437         if (time_before(jiffies, t->err_time + IP6TUNNEL_ERR_TIMEO))
 438                 t->err_count++;
 439         else
 440                 t->err_count = 1;
 441         t->err_time = jiffies;
 442 }
 443
 444 static int ip6gre_rcv(struct sk_buff *skb)
 445 {
 446         const struct ipv6hdr *ipv6h;
 447         u8     *h;
 448         __be16    flags;
 449         __sum16   csum = 0;
 450         __be32 key = 0;
 451         u32    seqno = 0;
 452         struct ip6_tnl *tunnel;
 453         int    offset = 4;
 454         __be16 gre_proto;
 455         int err;
 456
 457         if (!pskb_may_pull(skb, sizeof(struct in6_addr)))
 458                 goto drop;
 459
 460         ipv6h = ipv6_hdr(skb);
 461         h = skb->data;
 462         flags = *(__be16 *)h;
 463
 464         if (flags&(GRE_CSUM|GRE_KEY|GRE_ROUTING|GRE_SEQ|GRE_VERSION)) {
 465                 /* - Version must be 0.
 466                    - We do not support routing headers.
 467                  */
 468                 if (flags&(GRE_VERSION|GRE_ROUTING))
 469                         goto drop;
 470
 471                 if (flags&GRE_CSUM) {
 472                         switch (skb->ip_summed) {
 473                         case CHECKSUM_COMPLETE:
 474                                 csum = csum_fold(skb->csum);
 475                                 if (!csum)
 476                                         break;
 477                                 /* fall through */
 478                         case CHECKSUM_NONE:
 479                                 skb->csum = 0;
 480                                 csum = __skb_checksum_complete(skb);
 481                                 skb->ip_summed = CHECKSUM_COMPLETE;
 482                         }
 483                         offset += 4;
 484                 }
 485                 if (flags&GRE_KEY) {
 486                         key = *(__be32 *)(h + offset);
 487                         offset += 4;
 488                 }
 489                 if (flags&GRE_SEQ) {
 490                         seqno = ntohl(*(__be32 *)(h + offset));
 491                         offset += 4;
 492                 }
 493         }
 494
 495         gre_proto = *(__be16 *)(h + 2);
 496
 497         tunnel = ip6gre_tunnel_lookup(skb->dev,
 498                                           &ipv6h->saddr, &ipv6h->daddr, key,
 499                                           gre_proto);
 500         if (tunnel) {
 501                 struct pcpu_tstats *tstats;
 502
 503                 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
 504                         goto drop;
 505
 506                 if (!ip6_tnl_rcv_ctl(tunnel, &ipv6h->daddr, &ipv6h->saddr)) {
 507                         tunnel->dev->stats.rx_dropped++;
 508                         goto drop;
 509                 }
 510
 511                 secpath_reset(skb);
 512
 513                 skb->protocol = gre_proto;
 514                 /* WCCP version 1 and 2 protocol decoding.
 515                  * - Change protocol to IP
 516                  * - When dealing with WCCPv2, Skip extra 4 bytes in GRE header
 517                  */
 518                 if (flags == 0 && gre_proto == htons(ETH_P_WCCP)) {
 519                         skb->protocol = htons(ETH_P_IP);
 520                         if ((*(h + offset) & 0xF0) != 0x40)
 521                                 offset += 4;
 522                 }
 523
 524                 skb->mac_header = skb->network_header;
 525                 __pskb_pull(skb, offset);
 526                 skb_postpull_rcsum(skb, skb_transport_header(skb), offset);
 527                 skb->pkt_type = PACKET_HOST;
 528
 529                 if (((flags&GRE_CSUM) && csum) ||
 530                     (!(flags&GRE_CSUM) && tunnel->parms.i_flags&GRE_CSUM)) {
 531                         tunnel->dev->stats.rx_crc_errors++;
 532                         tunnel->dev->stats.rx_errors++;
 533                         goto drop;
 534                 }
 535                 if (tunnel->parms.i_flags&GRE_SEQ) {
 536                         if (!(flags&GRE_SEQ) ||
 537                             (tunnel->i_seqno &&
 538                                         (s32)(seqno - tunnel->i_seqno) < 0)) {
 539                                 tunnel->dev->stats.rx_fifo_errors++;
 540                                 tunnel->dev->stats.rx_errors++;
 541                                 goto drop;
 542                         }
 543                         tunnel->i_seqno = seqno + 1;
 544                 }
 545
 546                 /* Warning: All skb pointers will be invalidated! */
 547                 if (tunnel->dev->type == ARPHRD_ETHER) {
 548                         if (!pskb_may_pull(skb, ETH_HLEN)) {
 549                                 tunnel->dev->stats.rx_length_errors++;
 550                                 tunnel->dev->stats.rx_errors++;
 551                                 goto drop;
 552                         }
 553
 554                         ipv6h = ipv6_hdr(skb);
 555                         skb->protocol = eth_type_trans(skb, tunnel->dev);
 556                         skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);
 557                 }
 558
 559                 __skb_tunnel_rx(skb, tunnel->dev);
 560
 561                 skb_reset_network_header(skb);
 562
 563                 err = IP6_ECN_decapsulate(ipv6h, skb);
 564                 if (unlikely(err)) {
 565                         if (log_ecn_error)
 566                                 net_info_ratelimited("non-ECT from %pI6 with dsfield=%#x\n",
 567                                                      &ipv6h->saddr,
 568                                                      ipv6_get_dsfield(ipv6h));
 569                         if (err > 1) {
 570                                 ++tunnel->dev->stats.rx_frame_errors;
 571                                 ++tunnel->dev->stats.rx_errors;
 572                                 goto drop;
 573                         }
 574                 }
 575
 576                 tstats = this_cpu_ptr(tunnel->dev->tstats);
 577                 u64_stats_update_begin(&tstats->syncp);
 578                 tstats->rx_packets++;
 579                 tstats->rx_bytes += skb->len;
 580                 u64_stats_update_end(&tstats->syncp);
 581
 582                 netif_rx(skb);
 583
 584                 return 0;
 585         }
 586         icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
 587
 588 drop:
 589         kfree_skb(skb);
 590         return 0;
 591 }
 592
 593 struct ipv6_tel_txoption {
 594         struct ipv6_txoptions ops;
 595         __u8 dst_opt[8];
 596 };
 597
 598 static void init_tel_txopt(struct ipv6_tel_txoption *opt, __u8 encap_limit)
 599 {
 600         memset(opt, 0, sizeof(struct ipv6_tel_txoption));
 601
 602         opt->dst_opt[2] = IPV6_TLV_TNL_ENCAP_LIMIT;
 603         opt->dst_opt[3] = 1;
 604         opt->dst_opt[4] = encap_limit;
 605         opt->dst_opt[5] = IPV6_TLV_PADN;
 606         opt->dst_opt[6] = 1;
 607
 608         opt->ops.dst0opt = (struct ipv6_opt_hdr *) opt->dst_opt;
 609         opt->ops.opt_nflen = 8;
 610 }
 611
 612 static netdev_tx_t ip6gre_xmit2(struct sk_buff *skb,
 613                          struct net_device *dev,
 614                          __u8 dsfield,
 615                          struct flowi6 *fl6,
 616                          int encap_limit,
 617                          __u32 *pmtu)
 618 {
 619         struct net *net = dev_net(dev);
 620         struct ip6_tnl *tunnel = netdev_priv(dev);
 621         struct net_device *tdev;    /* Device to other host */
 622         struct ipv6hdr  *ipv6h;     /* Our new IP header */
 623         unsigned int max_headroom;  /* The extra header space needed */
 624         int    gre_hlen;
 625         struct ipv6_tel_txoption opt;
 626         int    mtu;
 627         struct dst_entry *dst = NULL, *ndst = NULL;
 628         struct net_device_stats *stats = &tunnel->dev->stats;
 629         int err = -1;
 630         u8 proto;
 631         struct sk_buff *new_skb;
 632
 633         if (dev->type == ARPHRD_ETHER)
 634                 IPCB(skb)->flags = 0;
 635
 636         if (dev->header_ops && dev->type == ARPHRD_IP6GRE) {
 637                 gre_hlen = 0;
 638                 ipv6h = (struct ipv6hdr *)skb->data;
 639                 fl6->daddr = ipv6h->daddr;
 640         } else {
 641                 gre_hlen = tunnel->hlen;
 642                 fl6->daddr = tunnel->parms.raddr;
 643         }
 644
 645         if (!fl6->flowi6_mark)
 646                 dst = ip6_tnl_dst_check(tunnel);
 647
 648         if (!dst) {
 649                 ndst = ip6_route_output(net, NULL, fl6);
 650
 651                 if (ndst->error)
 652                         goto tx_err_link_failure;
 653                 ndst = xfrm_lookup(net, ndst, flowi6_to_flowi(fl6), NULL, 0);
 654                 if (IS_ERR(ndst)) {
 655                         err = PTR_ERR(ndst);
 656                         ndst = NULL;
 657                         goto tx_err_link_failure;
 658                 }
 659                 dst = ndst;
 660         }
 661
 662         tdev = dst->dev;
 663
 664         if (tdev == dev) {
 665                 stats->collisions++;
 666                 net_warn_ratelimited("%s: Local routing loop detected!\n",
 667                                      tunnel->parms.name);
 668                 goto tx_err_dst_release;
 669         }
 670
 671         mtu = dst_mtu(dst) - sizeof(*ipv6h);
 672         if (encap_limit >= 0) {
 673                 max_headroom += 8;
 674                 mtu -= 8;
 675         }
 676         if (mtu < IPV6_MIN_MTU)
 677                 mtu = IPV6_MIN_MTU;
 678         if (skb_dst(skb))
 679                 skb_dst(skb)->ops->update_pmtu(skb_dst(skb), NULL, skb, mtu);
 680         if (skb->len > mtu) {
 681                 *pmtu = mtu;
 682                 err = -EMSGSIZE;
 683                 goto tx_err_dst_release;
 684         }
 685
 686         if (tunnel->err_count > 0) {
 687                 if (time_before(jiffies,
 688                                 tunnel->err_time + IP6TUNNEL_ERR_TIMEO)) {
 689                         tunnel->err_count--;
 690
 691                         dst_link_failure(skb);
 692                 } else
 693                         tunnel->err_count = 0;
 694         }
 695
 696         max_headroom = LL_RESERVED_SPACE(tdev) + gre_hlen + dst->header_len;
 697
 698         if (skb_headroom(skb) < max_headroom || skb_shared(skb) ||
 699             (skb_cloned(skb) && !skb_clone_writable(skb, 0))) {
 700                 new_skb = skb_realloc_headroom(skb, max_headroom);
 701                 if (max_headroom > dev->needed_headroom)
 702                         dev->needed_headroom = max_headroom;
 703                 if (!new_skb)
 704                         goto tx_err_dst_release;
 705
 706                 if (skb->sk)
 707                         skb_set_owner_w(new_skb, skb->sk);
 708                 consume_skb(skb);
 709                 skb = new_skb;
 710         }
 711
 712         skb_dst_drop(skb);
 713
 714         if (fl6->flowi6_mark) {
 715                 skb_dst_set(skb, dst);
 716                 ndst = NULL;
 717         } else {
 718                 skb_dst_set_noref(skb, dst);
 719         }
 720
 721         proto = NEXTHDR_GRE;
 722         if (encap_limit >= 0) {
 723                 init_tel_txopt(&opt, encap_limit);
 724                 ipv6_push_nfrag_opts(skb, &opt.ops, &proto, NULL);
 725         }
 726
 727         if (likely(!skb->encapsulation)) {
 728                 skb_reset_inner_headers(skb);
 729                 skb->encapsulation = 1;
 730         }
 731
 732         skb_push(skb, gre_hlen);
 733         skb_reset_network_header(skb);
 734         skb_set_transport_header(skb, sizeof(*ipv6h));
 735
 736         /*
 737          *      Push down and install the IP header.
 738          */
 739         ipv6h = ipv6_hdr(skb);
 740         ip6_flow_hdr(ipv6h, INET_ECN_encapsulate(0, dsfield), fl6->flowlabel);
 741         ipv6h->hop_limit = tunnel->parms.hop_limit;
 742         ipv6h->nexthdr = proto;
 743         ipv6h->saddr = fl6->saddr;
 744         ipv6h->daddr = fl6->daddr;
 745
 746         ((__be16 *)(ipv6h + 1))[0] = tunnel->parms.o_flags;
 747         ((__be16 *)(ipv6h + 1))[1] = (dev->type == ARPHRD_ETHER) ?
 748                                    htons(ETH_P_TEB) : skb->protocol;
 749
 750         if (tunnel->parms.o_flags&(GRE_KEY|GRE_CSUM|GRE_SEQ)) {
 751                 __be32 *ptr = (__be32 *)(((u8 *)ipv6h) + tunnel->hlen - 4);
 752
 753                 if (tunnel->parms.o_flags&GRE_SEQ) {
 754                         ++tunnel->o_seqno;
 755                         *ptr = htonl(tunnel->o_seqno);
 756                         ptr--;
 757                 }
 758                 if (tunnel->parms.o_flags&GRE_KEY) {
 759                         *ptr = tunnel->parms.o_key;
 760                         ptr--;
 761                 }
 762                 if (tunnel->parms.o_flags&GRE_CSUM) {
 763                         *ptr = 0;
 764                         *(__sum16 *)ptr = ip_compute_csum((void *)(ipv6h+1),
 765                                 skb->len - sizeof(struct ipv6hdr));
 766                 }
 767         }
 768
 769         ip6tunnel_xmit(skb, dev);
 770         if (ndst)
 771                 ip6_tnl_dst_store(tunnel, ndst);
 772         return 0;
 773 tx_err_link_failure:
 774         stats->tx_carrier_errors++;
 775         dst_link_failure(skb);
 776 tx_err_dst_release:
 777         dst_release(ndst);
 778         return err;
 779 }
 780
 781 static inline int ip6gre_xmit_ipv4(struct sk_buff *skb, struct net_device *dev)
 782 {
 783         struct ip6_tnl *t = netdev_priv(dev);
 784         const struct iphdr  *iph = ip_hdr(skb);
 785         int encap_limit = -1;
 786         struct flowi6 fl6;
 787         __u8 dsfield;
 788         __u32 mtu;
 789         int err;
 790
 791         if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
 792                 encap_limit = t->parms.encap_limit;
 793
 794         memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
 795         fl6.flowi6_proto = IPPROTO_IPIP;
 796
 797         dsfield = ipv4_get_dsfield(iph);
 798
 799         if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
 800                 fl6.flowlabel |= htonl((__u32)iph->tos << IPV6_TCLASS_SHIFT)
 801                                           & IPV6_TCLASS_MASK;
 802         if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
 803                 fl6.flowi6_mark = skb->mark;
 804
 805         err = ip6gre_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu);
 806         if (err != 0) {
 807                 /* XXX: send ICMP error even if DF is not set. */
 808                 if (err == -EMSGSIZE)
 809                         icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
 810                                   htonl(mtu));
 811                 return -1;
 812         }
 813
 814         return 0;
 815 }
 816
 817 static inline int ip6gre_xmit_ipv6(struct sk_buff *skb, struct net_device *dev)
 818 {
 819         struct ip6_tnl *t = netdev_priv(dev);
 820         struct ipv6hdr *ipv6h = ipv6_hdr(skb);
 821         int encap_limit = -1;
 822         __u16 offset;
 823         struct flowi6 fl6;
 824         __u8 dsfield;
 825         __u32 mtu;
 826         int err;
 827
 828         if (ipv6_addr_equal(&t->parms.raddr, &ipv6h->saddr))
 829                 return -1;
 830
 831         offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb));
 832         if (offset > 0) {
 833                 struct ipv6_tlv_tnl_enc_lim *tel;
 834                 tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset];
 835                 if (tel->encap_limit == 0) {
 836                         icmpv6_send(skb, ICMPV6_PARAMPROB,
 837                                     ICMPV6_HDR_FIELD, offset + 2);
 838                         return -1;
 839                 }
 840                 encap_limit = tel->encap_limit - 1;
 841         } else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
 842                 encap_limit = t->parms.encap_limit;
 843
 844         memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
 845         fl6.flowi6_proto = IPPROTO_IPV6;
 846
 847         dsfield = ipv6_get_dsfield(ipv6h);
 848         if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
 849                 fl6.flowlabel |= (*(__be32 *) ipv6h & IPV6_TCLASS_MASK);
 850         if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL)
 851                 fl6.flowlabel |= (*(__be32 *) ipv6h & IPV6_FLOWLABEL_MASK);
 852         if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
 853                 fl6.flowi6_mark = skb->mark;
 854
 855         err = ip6gre_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu);
 856         if (err != 0) {
 857                 if (err == -EMSGSIZE)
 858                         icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
 859                 return -1;
 860         }
 861
 862         return 0;
 863 }
 864
 865 /**
 866  * ip6_tnl_addr_conflict - compare packet addresses to tunnel's own
 867  *   @t: the outgoing tunnel device
 868  *   @hdr: IPv6 header from the incoming packet
 869  *
 870  * Description:
 871  *   Avoid trivial tunneling loop by checking that tunnel exit-point
 872  *   doesn't match source of incoming packet.
 873  *
 874  * Return:
 875  *   1 if conflict,
 876  *   0 else
 877  **/
 878
 879 static inline bool ip6gre_tnl_addr_conflict(const struct ip6_tnl *t,
 880         const struct ipv6hdr *hdr)
 881 {
 882         return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr);
 883 }
 884
 885 static int ip6gre_xmit_other(struct sk_buff *skb, struct net_device *dev)
 886 {
 887         struct ip6_tnl *t = netdev_priv(dev);
 888         int encap_limit = -1;
 889         struct flowi6 fl6;
 890         __u32 mtu;
 891         int err;
 892
 893         if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
 894                 encap_limit = t->parms.encap_limit;
 895
 896         memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
 897         fl6.flowi6_proto = skb->protocol;
 898
 899         err = ip6gre_xmit2(skb, dev, 0, &fl6, encap_limit, &mtu);
 900
 901         return err;
 902 }
 903
 904 static netdev_tx_t ip6gre_tunnel_xmit(struct sk_buff *skb,
 905         struct net_device *dev)
 906 {
 907         struct ip6_tnl *t = netdev_priv(dev);
 908         struct net_device_stats *stats = &t->dev->stats;
 909         int ret;
 910
 911         if (!ip6_tnl_xmit_ctl(t))
 912                 goto tx_err;
 913
 914         switch (skb->protocol) {
 915         case htons(ETH_P_IP):
 916                 ret = ip6gre_xmit_ipv4(skb, dev);
 917                 break;
 918         case htons(ETH_P_IPV6):
 919                 ret = ip6gre_xmit_ipv6(skb, dev);
 920                 break;
 921         default:
 922                 ret = ip6gre_xmit_other(skb, dev);
 923                 break;
 924         }
 925
 926         if (ret < 0)
 927                 goto tx_err;
 928
 929         return NETDEV_TX_OK;
 930
 931 tx_err:
 932         stats->tx_errors++;
 933         stats->tx_dropped++;
 934         kfree_skb(skb);
 935         return NETDEV_TX_OK;
 936 }
 937
 938 static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu)
 939 {
 940         struct net_device *dev = t->dev;
 941         struct __ip6_tnl_parm *p = &t->parms;
 942         struct flowi6 *fl6 = &t->fl.u.ip6;
 943         int addend = sizeof(struct ipv6hdr) + 4;
 944
 945         if (dev->type != ARPHRD_ETHER) {
 946                 memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr));
 947                 memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr));
 948         }
 949
 950         /* Set up flowi template */
 951         fl6->saddr = p->laddr;
 952         fl6->daddr = p->raddr;
 953         fl6->flowi6_oif = p->link;
 954         fl6->flowlabel = 0;
 955
 956         if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS))
 957                 fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo;
 958         if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL))
 959                 fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo;
 960
 961         p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET);
 962         p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr);
 963
 964         if (p->flags&IP6_TNL_F_CAP_XMIT &&
 965                         p->flags&IP6_TNL_F_CAP_RCV && dev->type != ARPHRD_ETHER)
 966                 dev->flags |= IFF_POINTOPOINT;
 967         else
 968                 dev->flags &= ~IFF_POINTOPOINT;
 969
 970         dev->iflink = p->link;
 971
 972         /* Precalculate GRE options length */
 973         if (t->parms.o_flags&(GRE_CSUM|GRE_KEY|GRE_SEQ)) {
 974                 if (t->parms.o_flags&GRE_CSUM)
 975                         addend += 4;
 976                 if (t->parms.o_flags&GRE_KEY)
 977                         addend += 4;
 978                 if (t->parms.o_flags&GRE_SEQ)
 979                         addend += 4;
 980         }
 981
 982         if (p->flags & IP6_TNL_F_CAP_XMIT) {
 983                 int strict = (ipv6_addr_type(&p->raddr) &
 984                               (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL));
 985
 986                 struct rt6_info *rt = rt6_lookup(dev_net(dev),
 987                                                  &p->raddr, &p->laddr,
 988                                                  p->link, strict);
 989
 990                 if (rt == NULL)
 991                         return;
 992
 993                 if (rt->dst.dev) {
 994                         dev->hard_header_len = rt->dst.dev->hard_header_len + addend;
 995
 996                         if (set_mtu) {
 997                                 dev->mtu = rt->dst.dev->mtu - addend;
 998                                 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
 999                                         dev->mtu -= 8;
1000
1001                                 if (dev->mtu < IPV6_MIN_MTU)
1002                                         dev->mtu = IPV6_MIN_MTU;
1003                         }
1004                 }
1005                 ip6_rt_put(rt);
1006         }
1007
1008         t->hlen = addend;
1009 }
1010
1011 static int ip6gre_tnl_change(struct ip6_tnl *t,
1012         const struct __ip6_tnl_parm *p, int set_mtu)
1013 {
1014         t->parms.laddr = p->laddr;
1015         t->parms.raddr = p->raddr;
1016         t->parms.flags = p->flags;
1017         t->parms.hop_limit = p->hop_limit;
1018         t->parms.encap_limit = p->encap_limit;
1019         t->parms.flowinfo = p->flowinfo;
1020         t->parms.link = p->link;
1021         t->parms.proto = p->proto;
1022         t->parms.i_key = p->i_key;
1023         t->parms.o_key = p->o_key;
1024         t->parms.i_flags = p->i_flags;
1025         t->parms.o_flags = p->o_flags;
1026         ip6_tnl_dst_reset(t);
1027         ip6gre_tnl_link_config(t, set_mtu);
1028         return 0;
1029 }
1030
1031 static void ip6gre_tnl_parm_from_user(struct __ip6_tnl_parm *p,
1032         const struct ip6_tnl_parm2 *u)
1033 {
1034         p->laddr = u->laddr;
1035         p->raddr = u->raddr;
1036         p->flags = u->flags;
1037         p->hop_limit = u->hop_limit;
1038         p->encap_limit = u->encap_limit;
1039         p->flowinfo = u->flowinfo;
1040         p->link = u->link;
1041         p->i_key = u->i_key;
1042         p->o_key = u->o_key;
1043         p->i_flags = u->i_flags;
1044         p->o_flags = u->o_flags;
1045         memcpy(p->name, u->name, sizeof(u->name));
1046 }
1047
1048 static void ip6gre_tnl_parm_to_user(struct ip6_tnl_parm2 *u,
1049         const struct __ip6_tnl_parm *p)
1050 {
1051         u->proto = IPPROTO_GRE;
1052         u->laddr = p->laddr;
1053         u->raddr = p->raddr;
1054         u->flags = p->flags;
1055         u->hop_limit = p->hop_limit;
1056         u->encap_limit = p->encap_limit;
1057         u->flowinfo = p->flowinfo;
1058         u->link = p->link;
1059         u->i_key = p->i_key;
1060         u->o_key = p->o_key;
1061         u->i_flags = p->i_flags;
1062         u->o_flags = p->o_flags;
1063         memcpy(u->name, p->name, sizeof(u->name));
1064 }
1065
1066 static int ip6gre_tunnel_ioctl(struct net_device *dev,
1067         struct ifreq *ifr, int cmd)
1068 {
1069         int err = 0;
1070         struct ip6_tnl_parm2 p;
1071         struct __ip6_tnl_parm p1;
1072         struct ip6_tnl *t;
1073         struct net *net = dev_net(dev);
1074         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1075
1076         switch (cmd) {
1077         case SIOCGETTUNNEL:
1078                 t = NULL;
1079                 if (dev == ign->fb_tunnel_dev) {
1080                         if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
1081                                 err = -EFAULT;
1082                                 break;
1083                         }
1084                         ip6gre_tnl_parm_from_user(&p1, &p);
1085                         t = ip6gre_tunnel_locate(net, &p1, 0);
1086                 }
1087                 if (t == NULL)
1088                         t = netdev_priv(dev);
1089                 memset(&p, 0, sizeof(p));
1090                 ip6gre_tnl_parm_to_user(&p, &t->parms);
1091                 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
1092                         err = -EFAULT;
1093                 break;
1094
1095         case SIOCADDTUNNEL:
1096         case SIOCCHGTUNNEL:
1097                 err = -EPERM;
1098                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1099                         goto done;
1100
1101                 err = -EFAULT;
1102                 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
1103                         goto done;
1104
1105                 err = -EINVAL;
1106                 if ((p.i_flags|p.o_flags)&(GRE_VERSION|GRE_ROUTING))
1107                         goto done;
1108
1109                 if (!(p.i_flags&GRE_KEY))
1110                         p.i_key = 0;
1111                 if (!(p.o_flags&GRE_KEY))
1112                         p.o_key = 0;
1113
1114                 ip6gre_tnl_parm_from_user(&p1, &p);
1115                 t = ip6gre_tunnel_locate(net, &p1, cmd == SIOCADDTUNNEL);
1116
1117                 if (dev != ign->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
1118                         if (t != NULL) {
1119                                 if (t->dev != dev) {
1120                                         err = -EEXIST;
1121                                         break;
1122                                 }
1123                         } else {
1124                                 t = netdev_priv(dev);
1125
1126                                 ip6gre_tunnel_unlink(ign, t);
1127                                 synchronize_net();
1128                                 ip6gre_tnl_change(t, &p1, 1);
1129                                 ip6gre_tunnel_link(ign, t);
1130                                 netdev_state_change(dev);
1131                         }
1132                 }
1133
1134                 if (t) {
1135                         err = 0;
1136
1137                         memset(&p, 0, sizeof(p));
1138                         ip6gre_tnl_parm_to_user(&p, &t->parms);
1139                         if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
1140                                 err = -EFAULT;
1141                 } else
1142                         err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
1143                 break;
1144
1145         case SIOCDELTUNNEL:
1146                 err = -EPERM;
1147                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1148                         goto done;
1149
1150                 if (dev == ign->fb_tunnel_dev) {
1151                         err = -EFAULT;
1152                         if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
1153                                 goto done;
1154                         err = -ENOENT;
1155                         ip6gre_tnl_parm_from_user(&p1, &p);
1156                         t = ip6gre_tunnel_locate(net, &p1, 0);
1157                         if (t == NULL)
1158                                 goto done;
1159                         err = -EPERM;
1160                         if (t == netdev_priv(ign->fb_tunnel_dev))
1161                                 goto done;
1162                         dev = t->dev;
1163                 }
1164                 unregister_netdevice(dev);
1165                 err = 0;
1166                 break;
1167
1168         default:
1169                 err = -EINVAL;
1170         }
1171
1172 done:
1173         return err;
1174 }
1175
1176 static int ip6gre_tunnel_change_mtu(struct net_device *dev, int new_mtu)
1177 {
1178         struct ip6_tnl *tunnel = netdev_priv(dev);
1179         if (new_mtu < 68 ||
1180             new_mtu > 0xFFF8 - dev->hard_header_len - tunnel->hlen)
1181                 return -EINVAL;
1182         dev->mtu = new_mtu;
1183         return 0;
1184 }
1185
1186 static int ip6gre_header(struct sk_buff *skb, struct net_device *dev,
1187                         unsigned short type,
1188                         const void *daddr, const void *saddr, unsigned int len)
1189 {
1190         struct ip6_tnl *t = netdev_priv(dev);
1191         struct ipv6hdr *ipv6h = (struct ipv6hdr *)skb_push(skb, t->hlen);
1192         __be16 *p = (__be16 *)(ipv6h+1);
1193
1194         ip6_flow_hdr(ipv6h, 0, t->fl.u.ip6.flowlabel);
1195         ipv6h->hop_limit = t->parms.hop_limit;
1196         ipv6h->nexthdr = NEXTHDR_GRE;
1197         ipv6h->saddr = t->parms.laddr;
1198         ipv6h->daddr = t->parms.raddr;
1199
1200         p[0]            = t->parms.o_flags;
1201         p[1]            = htons(type);
1202
1203         /*
1204          *      Set the source hardware address.
1205          */
1206
1207         if (saddr)
1208                 memcpy(&ipv6h->saddr, saddr, sizeof(struct in6_addr));
1209         if (daddr)
1210                 memcpy(&ipv6h->daddr, daddr, sizeof(struct in6_addr));
1211         if (!ipv6_addr_any(&ipv6h->daddr))
1212                 return t->hlen;
1213
1214         return -t->hlen;
1215 }
1216
1217 static const struct header_ops ip6gre_header_ops = {
1218         .create = ip6gre_header,
1219 };
1220
1221 static const struct net_device_ops ip6gre_netdev_ops = {
1222         .ndo_init               = ip6gre_tunnel_init,
1223         .ndo_uninit             = ip6gre_tunnel_uninit,
1224         .ndo_start_xmit         = ip6gre_tunnel_xmit,
1225         .ndo_do_ioctl           = ip6gre_tunnel_ioctl,
1226         .ndo_change_mtu         = ip6gre_tunnel_change_mtu,
1227         .ndo_get_stats64        = ip_tunnel_get_stats64,
1228 };
1229
1230 static void ip6gre_dev_free(struct net_device *dev)
1231 {
1232         free_percpu(dev->tstats);
1233         free_netdev(dev);
1234 }
1235
1236 static void ip6gre_tunnel_setup(struct net_device *dev)
1237 {
1238         struct ip6_tnl *t;
1239
1240         dev->netdev_ops = &ip6gre_netdev_ops;
1241         dev->destructor = ip6gre_dev_free;
1242
1243         dev->type = ARPHRD_IP6GRE;
1244         dev->hard_header_len = LL_MAX_HEADER + sizeof(struct ipv6hdr) + 4;
1245         dev->mtu = ETH_DATA_LEN - sizeof(struct ipv6hdr) - 4;
1246         t = netdev_priv(dev);
1247         if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1248                 dev->mtu -= 8;
1249         dev->flags |= IFF_NOARP;
1250         dev->iflink = 0;
1251         dev->addr_len = sizeof(struct in6_addr);
1252         dev->features |= NETIF_F_NETNS_LOCAL;
1253         dev->priv_flags &= ~IFF_XMIT_DST_RELEASE;
1254 }
1255
1256 static int ip6gre_tunnel_init(struct net_device *dev)
1257 {
1258         struct ip6_tnl *tunnel;
1259
1260         tunnel = netdev_priv(dev);
1261
1262         tunnel->dev = dev;
1263         strcpy(tunnel->parms.name, dev->name);
1264
1265         memcpy(dev->dev_addr, &tunnel->parms.laddr, sizeof(struct in6_addr));
1266         memcpy(dev->broadcast, &tunnel->parms.raddr, sizeof(struct in6_addr));
1267
1268         if (ipv6_addr_any(&tunnel->parms.raddr))
1269                 dev->header_ops = &ip6gre_header_ops;
1270
1271         dev->tstats = alloc_percpu(struct pcpu_tstats);
1272         if (!dev->tstats)
1273                 return -ENOMEM;
1274
1275         return 0;
1276 }
1277
1278 static void ip6gre_fb_tunnel_init(struct net_device *dev)
1279 {
1280         struct ip6_tnl *tunnel = netdev_priv(dev);
1281
1282         tunnel->dev = dev;
1283         strcpy(tunnel->parms.name, dev->name);
1284
1285         tunnel->hlen            = sizeof(struct ipv6hdr) + 4;
1286
1287         dev_hold(dev);
1288 }
1289
1290
1291 static struct inet6_protocol ip6gre_protocol __read_mostly = {
1292         .handler     = ip6gre_rcv,
1293         .err_handler = ip6gre_err,
1294         .flags       = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
1295 };
1296
1297 static void ip6gre_destroy_tunnels(struct ip6gre_net *ign,
1298         struct list_head *head)
1299 {
1300         int prio;
1301
1302         for (prio = 0; prio < 4; prio++) {
1303                 int h;
1304                 for (h = 0; h < HASH_SIZE; h++) {
1305                         struct ip6_tnl *t;
1306
1307                         t = rtnl_dereference(ign->tunnels[prio][h]);
1308
1309                         while (t != NULL) {
1310                                 unregister_netdevice_queue(t->dev, head);
1311                                 t = rtnl_dereference(t->next);
1312                         }
1313                 }
1314         }
1315 }
1316
1317 static int __net_init ip6gre_init_net(struct net *net)
1318 {
1319         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1320         int err;
1321
1322         ign->fb_tunnel_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6gre0",
1323                                            ip6gre_tunnel_setup);
1324         if (!ign->fb_tunnel_dev) {
1325                 err = -ENOMEM;
1326                 goto err_alloc_dev;
1327         }
1328         dev_net_set(ign->fb_tunnel_dev, net);
1329
1330         ip6gre_fb_tunnel_init(ign->fb_tunnel_dev);
1331         ign->fb_tunnel_dev->rtnl_link_ops = &ip6gre_link_ops;
1332
1333         err = register_netdev(ign->fb_tunnel_dev);
1334         if (err)
1335                 goto err_reg_dev;
1336
1337         rcu_assign_pointer(ign->tunnels_wc[0],
1338                            netdev_priv(ign->fb_tunnel_dev));
1339         return 0;
1340
1341 err_reg_dev:
1342         ip6gre_dev_free(ign->fb_tunnel_dev);
1343 err_alloc_dev:
1344         return err;
1345 }
1346
1347 static void __net_exit ip6gre_exit_net(struct net *net)
1348 {
1349         struct ip6gre_net *ign;
1350         LIST_HEAD(list);
1351
1352         ign = net_generic(net, ip6gre_net_id);
1353         rtnl_lock();
1354         ip6gre_destroy_tunnels(ign, &list);
1355         unregister_netdevice_many(&list);
1356         rtnl_unlock();
1357 }
1358
1359 static struct pernet_operations ip6gre_net_ops = {
1360         .init = ip6gre_init_net,
1361         .exit = ip6gre_exit_net,
1362         .id   = &ip6gre_net_id,
1363         .size = sizeof(struct ip6gre_net),
1364 };
1365
1366 static int ip6gre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[])
1367 {
1368         __be16 flags;
1369
1370         if (!data)
1371                 return 0;
1372
1373         flags = 0;
1374         if (data[IFLA_GRE_IFLAGS])
1375                 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
1376         if (data[IFLA_GRE_OFLAGS])
1377                 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
1378         if (flags & (GRE_VERSION|GRE_ROUTING))
1379                 return -EINVAL;
1380
1381         return 0;
1382 }
1383
1384 static int ip6gre_tap_validate(struct nlattr *tb[], struct nlattr *data[])
1385 {
1386         struct in6_addr daddr;
1387
1388         if (tb[IFLA_ADDRESS]) {
1389                 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
1390                         return -EINVAL;
1391                 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
1392                         return -EADDRNOTAVAIL;
1393         }
1394
1395         if (!data)
1396                 goto out;
1397
1398         if (data[IFLA_GRE_REMOTE]) {
1399                 nla_memcpy(&daddr, data[IFLA_GRE_REMOTE], sizeof(struct in6_addr));
1400                 if (ipv6_addr_any(&daddr))
1401                         return -EINVAL;
1402         }
1403
1404 out:
1405         return ip6gre_tunnel_validate(tb, data);
1406 }
1407
1408
1409 static void ip6gre_netlink_parms(struct nlattr *data[],
1410                                 struct __ip6_tnl_parm *parms)
1411 {
1412         memset(parms, 0, sizeof(*parms));
1413
1414         if (!data)
1415                 return;
1416
1417         if (data[IFLA_GRE_LINK])
1418                 parms->link = nla_get_u32(data[IFLA_GRE_LINK]);
1419
1420         if (data[IFLA_GRE_IFLAGS])
1421                 parms->i_flags = nla_get_be16(data[IFLA_GRE_IFLAGS]);
1422
1423         if (data[IFLA_GRE_OFLAGS])
1424                 parms->o_flags = nla_get_be16(data[IFLA_GRE_OFLAGS]);
1425
1426         if (data[IFLA_GRE_IKEY])
1427                 parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]);
1428
1429         if (data[IFLA_GRE_OKEY])
1430                 parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]);
1431
1432         if (data[IFLA_GRE_LOCAL])
1433                 nla_memcpy(&parms->laddr, data[IFLA_GRE_LOCAL], sizeof(struct in6_addr));
1434
1435         if (data[IFLA_GRE_REMOTE])
1436                 nla_memcpy(&parms->raddr, data[IFLA_GRE_REMOTE], sizeof(struct in6_addr));
1437
1438         if (data[IFLA_GRE_TTL])
1439                 parms->hop_limit = nla_get_u8(data[IFLA_GRE_TTL]);
1440
1441         if (data[IFLA_GRE_ENCAP_LIMIT])
1442                 parms->encap_limit = nla_get_u8(data[IFLA_GRE_ENCAP_LIMIT]);
1443
1444         if (data[IFLA_GRE_FLOWINFO])
1445                 parms->flowinfo = nla_get_u32(data[IFLA_GRE_FLOWINFO]);
1446
1447         if (data[IFLA_GRE_FLAGS])
1448                 parms->flags = nla_get_u32(data[IFLA_GRE_FLAGS]);
1449 }
1450
1451 static int ip6gre_tap_init(struct net_device *dev)
1452 {
1453         struct ip6_tnl *tunnel;
1454
1455         tunnel = netdev_priv(dev);
1456
1457         tunnel->dev = dev;
1458         strcpy(tunnel->parms.name, dev->name);
1459
1460         ip6gre_tnl_link_config(tunnel, 1);
1461
1462         dev->tstats = alloc_percpu(struct pcpu_tstats);
1463         if (!dev->tstats)
1464                 return -ENOMEM;
1465
1466         return 0;
1467 }
1468
1469 static const struct net_device_ops ip6gre_tap_netdev_ops = {
1470         .ndo_init = ip6gre_tap_init,
1471         .ndo_uninit = ip6gre_tunnel_uninit,
1472         .ndo_start_xmit = ip6gre_tunnel_xmit,
1473         .ndo_set_mac_address = eth_mac_addr,
1474         .ndo_validate_addr = eth_validate_addr,
1475         .ndo_change_mtu = ip6gre_tunnel_change_mtu,
1476         .ndo_get_stats64 = ip_tunnel_get_stats64,
1477 };
1478
1479 static void ip6gre_tap_setup(struct net_device *dev)
1480 {
1481
1482         ether_setup(dev);
1483
1484         dev->netdev_ops = &ip6gre_tap_netdev_ops;
1485         dev->destructor = ip6gre_dev_free;
1486
1487         dev->iflink = 0;
1488         dev->features |= NETIF_F_NETNS_LOCAL;
1489 }
1490
1491 static int ip6gre_newlink(struct net *src_net, struct net_device *dev,
1492         struct nlattr *tb[], struct nlattr *data[])
1493 {
1494         struct ip6_tnl *nt;
1495         struct net *net = dev_net(dev);
1496         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1497         int err;
1498
1499         nt = netdev_priv(dev);
1500         ip6gre_netlink_parms(data, &nt->parms);
1501
1502         if (ip6gre_tunnel_find(net, &nt->parms, dev->type))
1503                 return -EEXIST;
1504
1505         if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS])
1506                 eth_hw_addr_random(dev);
1507
1508         nt->dev = dev;
1509         ip6gre_tnl_link_config(nt, !tb[IFLA_MTU]);
1510
1511         /* Can use a lockless transmit, unless we generate output sequences */
1512         if (!(nt->parms.o_flags & GRE_SEQ))
1513                 dev->features |= NETIF_F_LLTX;
1514
1515         err = register_netdevice(dev);
1516         if (err)
1517                 goto out;
1518
1519         dev_hold(dev);
1520         ip6gre_tunnel_link(ign, nt);
1521
1522 out:
1523         return err;
1524 }
1525
1526 static int ip6gre_changelink(struct net_device *dev, struct nlattr *tb[],
1527                             struct nlattr *data[])
1528 {
1529         struct ip6_tnl *t, *nt;
1530         struct net *net = dev_net(dev);
1531         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1532         struct __ip6_tnl_parm p;
1533
1534         if (dev == ign->fb_tunnel_dev)
1535                 return -EINVAL;
1536
1537         nt = netdev_priv(dev);
1538         ip6gre_netlink_parms(data, &p);
1539
1540         t = ip6gre_tunnel_locate(net, &p, 0);
1541
1542         if (t) {
1543                 if (t->dev != dev)
1544                         return -EEXIST;
1545         } else {
1546                 t = nt;
1547
1548                 ip6gre_tunnel_unlink(ign, t);
1549                 ip6gre_tnl_change(t, &p, !tb[IFLA_MTU]);
1550                 ip6gre_tunnel_link(ign, t);
1551                 netdev_state_change(dev);
1552         }
1553
1554         return 0;
1555 }
1556
1557 static size_t ip6gre_get_size(const struct net_device *dev)
1558 {
1559         return
1560                 /* IFLA_GRE_LINK */
1561                 nla_total_size(4) +
1562                 /* IFLA_GRE_IFLAGS */
1563                 nla_total_size(2) +
1564                 /* IFLA_GRE_OFLAGS */
1565                 nla_total_size(2) +
1566                 /* IFLA_GRE_IKEY */
1567                 nla_total_size(4) +
1568                 /* IFLA_GRE_OKEY */
1569                 nla_total_size(4) +
1570                 /* IFLA_GRE_LOCAL */
1571                 nla_total_size(sizeof(struct in6_addr)) +
1572                 /* IFLA_GRE_REMOTE */
1573                 nla_total_size(sizeof(struct in6_addr)) +
1574                 /* IFLA_GRE_TTL */
1575                 nla_total_size(1) +
1576                 /* IFLA_GRE_TOS */
1577                 nla_total_size(1) +
1578                 /* IFLA_GRE_ENCAP_LIMIT */
1579                 nla_total_size(1) +
1580                 /* IFLA_GRE_FLOWINFO */
1581                 nla_total_size(4) +
1582                 /* IFLA_GRE_FLAGS */
1583                 nla_total_size(4) +
1584                 0;
1585 }
1586
1587 static int ip6gre_fill_info(struct sk_buff *skb, const struct net_device *dev)
1588 {
1589         struct ip6_tnl *t = netdev_priv(dev);
1590         struct __ip6_tnl_parm *p = &t->parms;
1591
1592         if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) ||
1593             nla_put_be16(skb, IFLA_GRE_IFLAGS, p->i_flags) ||
1594             nla_put_be16(skb, IFLA_GRE_OFLAGS, p->o_flags) ||
1595             nla_put_be32(skb, IFLA_GRE_IKEY, p->i_key) ||
1596             nla_put_be32(skb, IFLA_GRE_OKEY, p->o_key) ||
1597             nla_put(skb, IFLA_GRE_LOCAL, sizeof(struct in6_addr), &p->laddr) ||
1598             nla_put(skb, IFLA_GRE_REMOTE, sizeof(struct in6_addr), &p->raddr) ||
1599             nla_put_u8(skb, IFLA_GRE_TTL, p->hop_limit) ||
1600             /*nla_put_u8(skb, IFLA_GRE_TOS, t->priority) ||*/
1601             nla_put_u8(skb, IFLA_GRE_ENCAP_LIMIT, p->encap_limit) ||
1602             nla_put_be32(skb, IFLA_GRE_FLOWINFO, p->flowinfo) ||
1603             nla_put_u32(skb, IFLA_GRE_FLAGS, p->flags))
1604                 goto nla_put_failure;
1605         return 0;
1606
1607 nla_put_failure:
1608         return -EMSGSIZE;
1609 }
1610
1611 static const struct nla_policy ip6gre_policy[IFLA_GRE_MAX + 1] = {
1612         [IFLA_GRE_LINK]        = { .type = NLA_U32 },
1613         [IFLA_GRE_IFLAGS]      = { .type = NLA_U16 },
1614         [IFLA_GRE_OFLAGS]      = { .type = NLA_U16 },
1615         [IFLA_GRE_IKEY]        = { .type = NLA_U32 },
1616         [IFLA_GRE_OKEY]        = { .type = NLA_U32 },
1617         [IFLA_GRE_LOCAL]       = { .len = FIELD_SIZEOF(struct ipv6hdr, saddr) },
1618         [IFLA_GRE_REMOTE]      = { .len = FIELD_SIZEOF(struct ipv6hdr, daddr) },
1619         [IFLA_GRE_TTL]         = { .type = NLA_U8 },
1620         [IFLA_GRE_ENCAP_LIMIT] = { .type = NLA_U8 },
1621         [IFLA_GRE_FLOWINFO]    = { .type = NLA_U32 },
1622         [IFLA_GRE_FLAGS]       = { .type = NLA_U32 },
1623 };
1624
1625 static struct rtnl_link_ops ip6gre_link_ops __read_mostly = {
1626         .kind           = "ip6gre",
1627         .maxtype        = IFLA_GRE_MAX,
1628         .policy         = ip6gre_policy,
1629         .priv_size      = sizeof(struct ip6_tnl),
1630         .setup          = ip6gre_tunnel_setup,
1631         .validate       = ip6gre_tunnel_validate,
1632         .newlink        = ip6gre_newlink,
1633         .changelink     = ip6gre_changelink,
1634         .get_size       = ip6gre_get_size,
1635         .fill_info      = ip6gre_fill_info,
1636 };
1637
1638 static struct rtnl_link_ops ip6gre_tap_ops __read_mostly = {
1639         .kind           = "ip6gretap",
1640         .maxtype        = IFLA_GRE_MAX,
1641         .policy         = ip6gre_policy,
1642         .priv_size      = sizeof(struct ip6_tnl),
1643         .setup          = ip6gre_tap_setup,
1644         .validate       = ip6gre_tap_validate,
1645         .newlink        = ip6gre_newlink,
1646         .changelink     = ip6gre_changelink,
1647         .get_size       = ip6gre_get_size,
1648         .fill_info      = ip6gre_fill_info,
1649 };
1650
1651 /*
1652  *      And now the modules code and kernel interface.
1653  */
1654
1655 static int __init ip6gre_init(void)
1656 {
1657         int err;
1658
1659         pr_info("GRE over IPv6 tunneling driver\n");
1660
1661         err = register_pernet_device(&ip6gre_net_ops);
1662         if (err < 0)
1663                 return err;
1664
1665         err = inet6_add_protocol(&ip6gre_protocol, IPPROTO_GRE);
1666         if (err < 0) {
1667                 pr_info("%s: can't add protocol\n", __func__);
1668                 goto add_proto_failed;
1669         }
1670
1671         err = rtnl_link_register(&ip6gre_link_ops);
1672         if (err < 0)
1673                 goto rtnl_link_failed;
1674
1675         err = rtnl_link_register(&ip6gre_tap_ops);
1676         if (err < 0)
1677                 goto tap_ops_failed;
1678
1679 out:
1680         return err;
1681
1682 tap_ops_failed:
1683         rtnl_link_unregister(&ip6gre_link_ops);
1684 rtnl_link_failed:
1685         inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE);
1686 add_proto_failed:
1687         unregister_pernet_device(&ip6gre_net_ops);
1688         goto out;
1689 }
1690
1691 static void __exit ip6gre_fini(void)
1692 {
1693         rtnl_link_unregister(&ip6gre_tap_ops);
1694         rtnl_link_unregister(&ip6gre_link_ops);
1695         inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE);
1696         unregister_pernet_device(&ip6gre_net_ops);
1697 }
1698
1699 module_init(ip6gre_init);
1700 module_exit(ip6gre_fini);
1701 MODULE_LICENSE("GPL");
1702 MODULE_AUTHOR("D. Kozlov (xeb@mail.ru)");
1703 MODULE_DESCRIPTION("GRE over IPv6 tunneling device");
1704 MODULE_ALIAS_RTNL_LINK("ip6gre");
1705 MODULE_ALIAS_NETDEV("ip6gre0");