net/ipv4/ip_vti.c

   1 /*
   2  *      Linux NET3: IP/IP protocol decoder modified to support
   3  *                  virtual tunnel interface
   4  *
   5  *      Authors:
   6  *              Saurabh Mohan (saurabh.mohan@vyatta.com) 05/07/2012
   7  *
   8  *      This program is free software; you can redistribute it and/or
   9  *      modify it under the terms of the GNU General Public License
  10  *      as published by the Free Software Foundation; either version
  11  *      2 of the License, or (at your option) any later version.
  12  *
  13  */
  14
  15 /*
  16    This version of net/ipv4/ip_vti.c is cloned of net/ipv4/ipip.c
  17
  18    For comments look at net/ipv4/ip_gre.c --ANK
  19  */
  20
  21
  22 #include <linux/capability.h>
  23 #include <linux/module.h>
  24 #include <linux/types.h>
  25 #include <linux/kernel.h>
  26 #include <linux/uaccess.h>
  27 #include <linux/skbuff.h>
  28 #include <linux/netdevice.h>
  29 #include <linux/in.h>
  30 #include <linux/tcp.h>
  31 #include <linux/udp.h>
  32 #include <linux/if_arp.h>
  33 #include <linux/mroute.h>
  34 #include <linux/init.h>
  35 #include <linux/netfilter_ipv4.h>
  36 #include <linux/if_ether.h>
  37
  38 #include <net/sock.h>
  39 #include <net/ip.h>
  40 #include <net/icmp.h>
  41 #include <net/ipip.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
  47 #define HASH_SIZE  16
  48 #define HASH(addr) (((__force u32)addr^((__force u32)addr>>4))&(HASH_SIZE-1))
  49
  50 static struct rtnl_link_ops vti_link_ops __read_mostly;
  51
  52 static int vti_net_id __read_mostly;
  53 struct vti_net {
  54         struct ip_tunnel __rcu *tunnels_r_l[HASH_SIZE];
  55         struct ip_tunnel __rcu *tunnels_r[HASH_SIZE];
  56         struct ip_tunnel __rcu *tunnels_l[HASH_SIZE];
  57         struct ip_tunnel __rcu *tunnels_wc[1];
  58         struct ip_tunnel __rcu **tunnels[4];
  59
  60         struct net_device *fb_tunnel_dev;
  61 };
  62
  63 static int vti_fb_tunnel_init(struct net_device *dev);
  64 static int vti_tunnel_init(struct net_device *dev);
  65 static void vti_tunnel_setup(struct net_device *dev);
  66 static void vti_dev_free(struct net_device *dev);
  67 static int vti_tunnel_bind_dev(struct net_device *dev);
  68
  69 /* Locking : hash tables are protected by RCU and RTNL */
  70
  71 #define for_each_ip_tunnel_rcu(start) \
  72         for (t = rcu_dereference(start); t; t = rcu_dereference(t->next))
  73
  74 /* often modified stats are per cpu, other are shared (netdev->stats) */
  75 struct pcpu_tstats {
  76         u64     rx_packets;
  77         u64     rx_bytes;
  78         u64     tx_packets;
  79         u64     tx_bytes;
  80         struct  u64_stats_sync  syncp;
  81 };
  82
  83 #define VTI_XMIT(stats1, stats2) do {                           \
  84         int err;                                                \
  85         int pkt_len = skb->len;                                 \
  86         err = dst_output(skb);                                  \
  87         if (net_xmit_eval(err) == 0) {                          \
  88                 u64_stats_update_begin(&(stats1)->syncp);       \
  89                 (stats1)->tx_bytes += pkt_len;                  \
  90                 (stats1)->tx_packets++;                         \
  91                 u64_stats_update_end(&(stats1)->syncp);         \
  92         } else {                                                \
  93                 (stats2)->tx_errors++;                          \
  94                 (stats2)->tx_aborted_errors++;                  \
  95         }                                                       \
  96 } while (0)
  97
  98
  99 static struct rtnl_link_stats64 *vti_get_stats64(struct net_device *dev,
 100                                                  struct rtnl_link_stats64 *tot)
 101 {
 102         int i;
 103
 104         for_each_possible_cpu(i) {
 105                 const struct pcpu_tstats *tstats = per_cpu_ptr(dev->tstats, i);
 106                 u64 rx_packets, rx_bytes, tx_packets, tx_bytes;
 107                 unsigned int start;
 108
 109                 do {
 110                         start = u64_stats_fetch_begin_bh(&tstats->syncp);
 111                         rx_packets = tstats->rx_packets;
 112                         tx_packets = tstats->tx_packets;
 113                         rx_bytes = tstats->rx_bytes;
 114                         tx_bytes = tstats->tx_bytes;
 115                 } while (u64_stats_fetch_retry_bh(&tstats->syncp, start));
 116
 117                 tot->rx_packets += rx_packets;
 118                 tot->tx_packets += tx_packets;
 119                 tot->rx_bytes   += rx_bytes;
 120                 tot->tx_bytes   += tx_bytes;
 121         }
 122
 123         tot->multicast = dev->stats.multicast;
 124         tot->rx_crc_errors = dev->stats.rx_crc_errors;
 125         tot->rx_fifo_errors = dev->stats.rx_fifo_errors;
 126         tot->rx_length_errors = dev->stats.rx_length_errors;
 127         tot->rx_errors = dev->stats.rx_errors;
 128         tot->tx_fifo_errors = dev->stats.tx_fifo_errors;
 129         tot->tx_carrier_errors = dev->stats.tx_carrier_errors;
 130         tot->tx_dropped = dev->stats.tx_dropped;
 131         tot->tx_aborted_errors = dev->stats.tx_aborted_errors;
 132         tot->tx_errors = dev->stats.tx_errors;
 133
 134         return tot;
 135 }
 136
 137 static struct ip_tunnel *vti_tunnel_lookup(struct net *net,
 138                                            __be32 remote, __be32 local)
 139 {
 140         unsigned h0 = HASH(remote);
 141         unsigned h1 = HASH(local);
 142         struct ip_tunnel *t;
 143         struct vti_net *ipn = net_generic(net, vti_net_id);
 144
 145         for_each_ip_tunnel_rcu(ipn->tunnels_r_l[h0 ^ h1])
 146                 if (local == t->parms.iph.saddr &&
 147                     remote == t->parms.iph.daddr && (t->dev->flags&IFF_UP))
 148                         return t;
 149         for_each_ip_tunnel_rcu(ipn->tunnels_r[h0])
 150                 if (remote == t->parms.iph.daddr && (t->dev->flags&IFF_UP))
 151                         return t;
 152
 153         for_each_ip_tunnel_rcu(ipn->tunnels_l[h1])
 154                 if (local == t->parms.iph.saddr && (t->dev->flags&IFF_UP))
 155                         return t;
 156
 157         for_each_ip_tunnel_rcu(ipn->tunnels_wc[0])
 158                 if (t && (t->dev->flags&IFF_UP))
 159                         return t;
 160         return NULL;
 161 }
 162
 163 static struct ip_tunnel __rcu **__vti_bucket(struct vti_net *ipn,
 164                                              struct ip_tunnel_parm *parms)
 165 {
 166         __be32 remote = parms->iph.daddr;
 167         __be32 local = parms->iph.saddr;
 168         unsigned h = 0;
 169         int prio = 0;
 170
 171         if (remote) {
 172                 prio |= 2;
 173                 h ^= HASH(remote);
 174         }
 175         if (local) {
 176                 prio |= 1;
 177                 h ^= HASH(local);
 178         }
 179         return &ipn->tunnels[prio][h];
 180 }
 181
 182 static inline struct ip_tunnel __rcu **vti_bucket(struct vti_net *ipn,
 183                                                   struct ip_tunnel *t)
 184 {
 185         return __vti_bucket(ipn, &t->parms);
 186 }
 187
 188 static void vti_tunnel_unlink(struct vti_net *ipn, struct ip_tunnel *t)
 189 {
 190         struct ip_tunnel __rcu **tp;
 191         struct ip_tunnel *iter;
 192
 193         for (tp = vti_bucket(ipn, t);
 194              (iter = rtnl_dereference(*tp)) != NULL;
 195              tp = &iter->next) {
 196                 if (t == iter) {
 197                         rcu_assign_pointer(*tp, t->next);
 198                         break;
 199                 }
 200         }
 201 }
 202
 203 static void vti_tunnel_link(struct vti_net *ipn, struct ip_tunnel *t)
 204 {
 205         struct ip_tunnel __rcu **tp = vti_bucket(ipn, t);
 206
 207         rcu_assign_pointer(t->next, rtnl_dereference(*tp));
 208         rcu_assign_pointer(*tp, t);
 209 }
 210
 211 static struct ip_tunnel *vti_tunnel_locate(struct net *net,
 212                                            struct ip_tunnel_parm *parms,
 213                                            int create)
 214 {
 215         __be32 remote = parms->iph.daddr;
 216         __be32 local = parms->iph.saddr;
 217         struct ip_tunnel *t, *nt;
 218         struct ip_tunnel __rcu **tp;
 219         struct net_device *dev;
 220         char name[IFNAMSIZ];
 221         struct vti_net *ipn = net_generic(net, vti_net_id);
 222
 223         for (tp = __vti_bucket(ipn, parms);
 224              (t = rtnl_dereference(*tp)) != NULL;
 225              tp = &t->next) {
 226                 if (local == t->parms.iph.saddr && remote == t->parms.iph.daddr)
 227                         return t;
 228         }
 229         if (!create)
 230                 return NULL;
 231
 232         if (parms->name[0])
 233                 strlcpy(name, parms->name, IFNAMSIZ);
 234         else
 235                 strcpy(name, "vti%d");
 236
 237         dev = alloc_netdev(sizeof(*t), name, vti_tunnel_setup);
 238         if (dev == NULL)
 239                 return NULL;
 240
 241         dev_net_set(dev, net);
 242
 243         nt = netdev_priv(dev);
 244         nt->parms = *parms;
 245         dev->rtnl_link_ops = &vti_link_ops;
 246
 247         vti_tunnel_bind_dev(dev);
 248
 249         if (register_netdevice(dev) < 0)
 250                 goto failed_free;
 251
 252         dev_hold(dev);
 253         vti_tunnel_link(ipn, nt);
 254         return nt;
 255
 256 failed_free:
 257         free_netdev(dev);
 258         return NULL;
 259 }
 260
 261 static void vti_tunnel_uninit(struct net_device *dev)
 262 {
 263         struct net *net = dev_net(dev);
 264         struct vti_net *ipn = net_generic(net, vti_net_id);
 265
 266         vti_tunnel_unlink(ipn, netdev_priv(dev));
 267         dev_put(dev);
 268 }
 269
 270 static int vti_err(struct sk_buff *skb, u32 info)
 271 {
 272
 273         /* All the routers (except for Linux) return only
 274          * 8 bytes of packet payload. It means, that precise relaying of
 275          * ICMP in the real Internet is absolutely infeasible.
 276          */
 277         struct iphdr *iph = (struct iphdr *)skb->data;
 278         const int type = icmp_hdr(skb)->type;
 279         const int code = icmp_hdr(skb)->code;
 280         struct ip_tunnel *t;
 281         int err;
 282
 283         switch (type) {
 284         default:
 285         case ICMP_PARAMETERPROB:
 286                 return 0;
 287
 288         case ICMP_DEST_UNREACH:
 289                 switch (code) {
 290                 case ICMP_SR_FAILED:
 291                 case ICMP_PORT_UNREACH:
 292                         /* Impossible event. */
 293                         return 0;
 294                 default:
 295                         /* All others are translated to HOST_UNREACH. */
 296                         break;
 297                 }
 298                 break;
 299         case ICMP_TIME_EXCEEDED:
 300                 if (code != ICMP_EXC_TTL)
 301                         return 0;
 302                 break;
 303         }
 304
 305         err = -ENOENT;
 306
 307         t = vti_tunnel_lookup(dev_net(skb->dev), iph->daddr, iph->saddr);
 308         if (t == NULL)
 309                 goto out;
 310
 311         if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) {
 312                 ipv4_update_pmtu(skb, dev_net(skb->dev), info,
 313                                  t->parms.link, 0, IPPROTO_IPIP, 0);
 314                 err = 0;
 315                 goto out;
 316         }
 317
 318         err = 0;
 319         if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
 320                 goto out;
 321
 322         if (time_before(jiffies, t->err_time + IPTUNNEL_ERR_TIMEO))
 323                 t->err_count++;
 324         else
 325                 t->err_count = 1;
 326         t->err_time = jiffies;
 327 out:
 328         return err;
 329 }
 330
 331 /* We dont digest the packet therefore let the packet pass */
 332 static int vti_rcv(struct sk_buff *skb)
 333 {
 334         struct ip_tunnel *tunnel;
 335         const struct iphdr *iph = ip_hdr(skb);
 336
 337         tunnel = vti_tunnel_lookup(dev_net(skb->dev), iph->saddr, iph->daddr);
 338         if (tunnel != NULL) {
 339                 struct pcpu_tstats *tstats;
 340
 341                 if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb))
 342                         return -1;
 343
 344                 tstats = this_cpu_ptr(tunnel->dev->tstats);
 345                 u64_stats_update_begin(&tstats->syncp);
 346                 tstats->rx_packets++;
 347                 tstats->rx_bytes += skb->len;
 348                 u64_stats_update_end(&tstats->syncp);
 349
 350                 skb->mark = 0;
 351                 secpath_reset(skb);
 352                 skb->dev = tunnel->dev;
 353                 return 1;
 354         }
 355
 356         return -1;
 357 }
 358
 359 /* This function assumes it is being called from dev_queue_xmit()
 360  * and that skb is filled properly by that function.
 361  */
 362
 363 static netdev_tx_t vti_tunnel_xmit(struct sk_buff *skb, struct net_device *dev)
 364 {
 365         struct ip_tunnel *tunnel = netdev_priv(dev);
 366         struct pcpu_tstats *tstats;
 367         struct iphdr  *tiph = &tunnel->parms.iph;
 368         u8     tos;
 369         struct rtable *rt;              /* Route to the other host */
 370         struct net_device *tdev;        /* Device to other host */
 371         struct iphdr  *old_iph = ip_hdr(skb);
 372         __be32 dst = tiph->daddr;
 373         struct flowi4 fl4;
 374
 375         if (skb->protocol != htons(ETH_P_IP))
 376                 goto tx_error;
 377
 378         tos = old_iph->tos;
 379
 380         memset(&fl4, 0, sizeof(fl4));
 381         flowi4_init_output(&fl4, tunnel->parms.link,
 382                            be32_to_cpu(tunnel->parms.i_key), RT_TOS(tos),
 383                            RT_SCOPE_UNIVERSE,
 384                            IPPROTO_IPIP, 0,
 385                            dst, tiph->saddr, 0, 0);
 386         rt = ip_route_output_key(dev_net(dev), &fl4);
 387         if (IS_ERR(rt)) {
 388                 dev->stats.tx_carrier_errors++;
 389                 goto tx_error_icmp;
 390         }
 391         /* if there is no transform then this tunnel is not functional.
 392          * Or if the xfrm is not mode tunnel.
 393          */
 394         if (!rt->dst.xfrm ||
 395             rt->dst.xfrm->props.mode != XFRM_MODE_TUNNEL) {
 396                 dev->stats.tx_carrier_errors++;
 397                 goto tx_error_icmp;
 398         }
 399         tdev = rt->dst.dev;
 400
 401         if (tdev == dev) {
 402                 ip_rt_put(rt);
 403                 dev->stats.collisions++;
 404                 goto tx_error;
 405         }
 406
 407         if (tunnel->err_count > 0) {
 408                 if (time_before(jiffies,
 409                                 tunnel->err_time + IPTUNNEL_ERR_TIMEO)) {
 410                         tunnel->err_count--;
 411                         dst_link_failure(skb);
 412                 } else
 413                         tunnel->err_count = 0;
 414         }
 415
 416         IPCB(skb)->flags &= ~(IPSKB_XFRM_TUNNEL_SIZE | IPSKB_XFRM_TRANSFORMED |
 417                               IPSKB_REROUTED);
 418         skb_dst_drop(skb);
 419         skb_dst_set(skb, &rt->dst);
 420         nf_reset(skb);
 421         skb->dev = skb_dst(skb)->dev;
 422
 423         tstats = this_cpu_ptr(dev->tstats);
 424         VTI_XMIT(tstats, &dev->stats);
 425         return NETDEV_TX_OK;
 426
 427 tx_error_icmp:
 428         dst_link_failure(skb);
 429 tx_error:
 430         dev->stats.tx_errors++;
 431         dev_kfree_skb(skb);
 432         return NETDEV_TX_OK;
 433 }
 434
 435 static int vti_tunnel_bind_dev(struct net_device *dev)
 436 {
 437         struct net_device *tdev = NULL;
 438         struct ip_tunnel *tunnel;
 439         struct iphdr *iph;
 440
 441         tunnel = netdev_priv(dev);
 442         iph = &tunnel->parms.iph;
 443
 444         if (iph->daddr) {
 445                 struct rtable *rt;
 446                 struct flowi4 fl4;
 447                 memset(&fl4, 0, sizeof(fl4));
 448                 flowi4_init_output(&fl4, tunnel->parms.link,
 449                                    be32_to_cpu(tunnel->parms.i_key),
 450                                    RT_TOS(iph->tos), RT_SCOPE_UNIVERSE,
 451                                    IPPROTO_IPIP, 0,
 452                                    iph->daddr, iph->saddr, 0, 0);
 453                 rt = ip_route_output_key(dev_net(dev), &fl4);
 454                 if (!IS_ERR(rt)) {
 455                         tdev = rt->dst.dev;
 456                         ip_rt_put(rt);
 457                 }
 458                 dev->flags |= IFF_POINTOPOINT;
 459         }
 460
 461         if (!tdev && tunnel->parms.link)
 462                 tdev = __dev_get_by_index(dev_net(dev), tunnel->parms.link);
 463
 464         if (tdev) {
 465                 dev->hard_header_len = tdev->hard_header_len +
 466                                        sizeof(struct iphdr);
 467                 dev->mtu = tdev->mtu;
 468         }
 469         dev->iflink = tunnel->parms.link;
 470         return dev->mtu;
 471 }
 472
 473 static int
 474 vti_tunnel_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
 475 {
 476         int err = 0;
 477         struct ip_tunnel_parm p;
 478         struct ip_tunnel *t;
 479         struct net *net = dev_net(dev);
 480         struct vti_net *ipn = net_generic(net, vti_net_id);
 481
 482         switch (cmd) {
 483         case SIOCGETTUNNEL:
 484                 t = NULL;
 485                 if (dev == ipn->fb_tunnel_dev) {
 486                         if (copy_from_user(&p, ifr->ifr_ifru.ifru_data,
 487                                            sizeof(p))) {
 488                                 err = -EFAULT;
 489                                 break;
 490                         }
 491                         t = vti_tunnel_locate(net, &p, 0);
 492                 }
 493                 if (t == NULL)
 494                         t = netdev_priv(dev);
 495                 memcpy(&p, &t->parms, sizeof(p));
 496                 p.i_flags |= GRE_KEY | VTI_ISVTI;
 497                 p.o_flags |= GRE_KEY;
 498                 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
 499                         err = -EFAULT;
 500                 break;
 501
 502         case SIOCADDTUNNEL:
 503         case SIOCCHGTUNNEL:
 504                 err = -EPERM;
 505                 if (!capable(CAP_NET_ADMIN))
 506                         goto done;
 507
 508                 err = -EFAULT;
 509                 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
 510                         goto done;
 511
 512                 err = -EINVAL;
 513                 if (p.iph.version != 4 || p.iph.protocol != IPPROTO_IPIP ||
 514                     p.iph.ihl != 5)
 515                         goto done;
 516
 517                 t = vti_tunnel_locate(net, &p, cmd == SIOCADDTUNNEL);
 518
 519                 if (dev != ipn->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
 520                         if (t != NULL) {
 521                                 if (t->dev != dev) {
 522                                         err = -EEXIST;
 523                                         break;
 524                                 }
 525                         } else {
 526                                 if (((dev->flags&IFF_POINTOPOINT) &&
 527                                     !p.iph.daddr) ||
 528                                     (!(dev->flags&IFF_POINTOPOINT) &&
 529                                     p.iph.daddr)) {
 530                                         err = -EINVAL;
 531                                         break;
 532                                 }
 533                                 t = netdev_priv(dev);
 534                                 vti_tunnel_unlink(ipn, t);
 535                                 synchronize_net();
 536                                 t->parms.iph.saddr = p.iph.saddr;
 537                                 t->parms.iph.daddr = p.iph.daddr;
 538                                 t->parms.i_key = p.i_key;
 539                                 t->parms.o_key = p.o_key;
 540                                 t->parms.iph.protocol = IPPROTO_IPIP;
 541                                 memcpy(dev->dev_addr, &p.iph.saddr, 4);
 542                                 memcpy(dev->broadcast, &p.iph.daddr, 4);
 543                                 vti_tunnel_link(ipn, t);
 544                                 netdev_state_change(dev);
 545                         }
 546                 }
 547
 548                 if (t) {
 549                         err = 0;
 550                         if (cmd == SIOCCHGTUNNEL) {
 551                                 t->parms.i_key = p.i_key;
 552                                 t->parms.o_key = p.o_key;
 553                                 if (t->parms.link != p.link) {
 554                                         t->parms.link = p.link;
 555                                         vti_tunnel_bind_dev(dev);
 556                                         netdev_state_change(dev);
 557                                 }
 558                         }
 559                         p.i_flags |= GRE_KEY | VTI_ISVTI;
 560                         p.o_flags |= GRE_KEY;
 561                         if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms,
 562                                          sizeof(p)))
 563                                 err = -EFAULT;
 564                 } else
 565                         err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
 566                 break;
 567
 568         case SIOCDELTUNNEL:
 569                 err = -EPERM;
 570                 if (!capable(CAP_NET_ADMIN))
 571                         goto done;
 572
 573                 if (dev == ipn->fb_tunnel_dev) {
 574                         err = -EFAULT;
 575                         if (copy_from_user(&p, ifr->ifr_ifru.ifru_data,
 576                                            sizeof(p)))
 577                                 goto done;
 578                         err = -ENOENT;
 579
 580                         t = vti_tunnel_locate(net, &p, 0);
 581                         if (t == NULL)
 582                                 goto done;
 583                         err = -EPERM;
 584                         if (t->dev == ipn->fb_tunnel_dev)
 585                                 goto done;
 586                         dev = t->dev;
 587                 }
 588                 unregister_netdevice(dev);
 589                 err = 0;
 590                 break;
 591
 592         default:
 593                 err = -EINVAL;
 594         }
 595
 596 done:
 597         return err;
 598 }
 599
 600 static int vti_tunnel_change_mtu(struct net_device *dev, int new_mtu)
 601 {
 602         if (new_mtu < 68 || new_mtu > 0xFFF8)
 603                 return -EINVAL;
 604         dev->mtu = new_mtu;
 605         return 0;
 606 }
 607
 608 static const struct net_device_ops vti_netdev_ops = {
 609         .ndo_init       = vti_tunnel_init,
 610         .ndo_uninit     = vti_tunnel_uninit,
 611         .ndo_start_xmit = vti_tunnel_xmit,
 612         .ndo_do_ioctl   = vti_tunnel_ioctl,
 613         .ndo_change_mtu = vti_tunnel_change_mtu,
 614         .ndo_get_stats64 = vti_get_stats64,
 615 };
 616
 617 static void vti_dev_free(struct net_device *dev)
 618 {
 619         free_percpu(dev->tstats);
 620         free_netdev(dev);
 621 }
 622
 623 static void vti_tunnel_setup(struct net_device *dev)
 624 {
 625         dev->netdev_ops         = &vti_netdev_ops;
 626         dev->destructor         = vti_dev_free;
 627
 628         dev->type               = ARPHRD_TUNNEL;
 629         dev->hard_header_len    = LL_MAX_HEADER + sizeof(struct iphdr);
 630         dev->mtu                = ETH_DATA_LEN;
 631         dev->flags              = IFF_NOARP;
 632         dev->iflink             = 0;
 633         dev->addr_len           = 4;
 634         dev->features           |= NETIF_F_NETNS_LOCAL;
 635         dev->features           |= NETIF_F_LLTX;
 636         dev->priv_flags         &= ~IFF_XMIT_DST_RELEASE;
 637 }
 638
 639 static int vti_tunnel_init(struct net_device *dev)
 640 {
 641         struct ip_tunnel *tunnel = netdev_priv(dev);
 642
 643         tunnel->dev = dev;
 644         strcpy(tunnel->parms.name, dev->name);
 645
 646         memcpy(dev->dev_addr, &tunnel->parms.iph.saddr, 4);
 647         memcpy(dev->broadcast, &tunnel->parms.iph.daddr, 4);
 648
 649         dev->tstats = alloc_percpu(struct pcpu_tstats);
 650         if (!dev->tstats)
 651                 return -ENOMEM;
 652
 653         return 0;
 654 }
 655
 656 static int __net_init vti_fb_tunnel_init(struct net_device *dev)
 657 {
 658         struct ip_tunnel *tunnel = netdev_priv(dev);
 659         struct iphdr *iph = &tunnel->parms.iph;
 660         struct vti_net *ipn = net_generic(dev_net(dev), vti_net_id);
 661
 662         tunnel->dev = dev;
 663         strcpy(tunnel->parms.name, dev->name);
 664
 665         iph->version            = 4;
 666         iph->protocol           = IPPROTO_IPIP;
 667         iph->ihl                = 5;
 668
 669         dev->tstats = alloc_percpu(struct pcpu_tstats);
 670         if (!dev->tstats)
 671                 return -ENOMEM;
 672
 673         dev_hold(dev);
 674         rcu_assign_pointer(ipn->tunnels_wc[0], tunnel);
 675         return 0;
 676 }
 677
 678 static struct xfrm_tunnel vti_handler __read_mostly = {
 679         .handler        =       vti_rcv,
 680         .err_handler    =       vti_err,
 681         .priority       =       1,
 682 };
 683
 684 static void vti_destroy_tunnels(struct vti_net *ipn, struct list_head *head)
 685 {
 686         int prio;
 687
 688         for (prio = 1; prio < 4; prio++) {
 689                 int h;
 690                 for (h = 0; h < HASH_SIZE; h++) {
 691                         struct ip_tunnel *t;
 692
 693                         t = rtnl_dereference(ipn->tunnels[prio][h]);
 694                         while (t != NULL) {
 695                                 unregister_netdevice_queue(t->dev, head);
 696                                 t = rtnl_dereference(t->next);
 697                         }
 698                 }
 699         }
 700 }
 701
 702 static int __net_init vti_init_net(struct net *net)
 703 {
 704         int err;
 705         struct vti_net *ipn = net_generic(net, vti_net_id);
 706
 707         ipn->tunnels[0] = ipn->tunnels_wc;
 708         ipn->tunnels[1] = ipn->tunnels_l;
 709         ipn->tunnels[2] = ipn->tunnels_r;
 710         ipn->tunnels[3] = ipn->tunnels_r_l;
 711
 712         ipn->fb_tunnel_dev = alloc_netdev(sizeof(struct ip_tunnel),
 713                                           "ip_vti0",
 714                                           vti_tunnel_setup);
 715         if (!ipn->fb_tunnel_dev) {
 716                 err = -ENOMEM;
 717                 goto err_alloc_dev;
 718         }
 719         dev_net_set(ipn->fb_tunnel_dev, net);
 720
 721         err = vti_fb_tunnel_init(ipn->fb_tunnel_dev);
 722         if (err)
 723                 goto err_reg_dev;
 724         ipn->fb_tunnel_dev->rtnl_link_ops = &vti_link_ops;
 725
 726         err = register_netdev(ipn->fb_tunnel_dev);
 727         if (err)
 728                 goto err_reg_dev;
 729         return 0;
 730
 731 err_reg_dev:
 732         vti_dev_free(ipn->fb_tunnel_dev);
 733 err_alloc_dev:
 734         /* nothing */
 735         return err;
 736 }
 737
 738 static void __net_exit vti_exit_net(struct net *net)
 739 {
 740         struct vti_net *ipn = net_generic(net, vti_net_id);
 741         LIST_HEAD(list);
 742
 743         rtnl_lock();
 744         vti_destroy_tunnels(ipn, &list);
 745         unregister_netdevice_many(&list);
 746         rtnl_unlock();
 747 }
 748
 749 static struct pernet_operations vti_net_ops = {
 750         .init = vti_init_net,
 751         .exit = vti_exit_net,
 752         .id   = &vti_net_id,
 753         .size = sizeof(struct vti_net),
 754 };
 755
 756 static int vti_tunnel_validate(struct nlattr *tb[], struct nlattr *data[])
 757 {
 758         return 0;
 759 }
 760
 761 static void vti_netlink_parms(struct nlattr *data[],
 762                               struct ip_tunnel_parm *parms)
 763 {
 764         memset(parms, 0, sizeof(*parms));
 765
 766         parms->iph.protocol = IPPROTO_IPIP;
 767
 768         if (!data)
 769                 return;
 770
 771         if (data[IFLA_VTI_LINK])
 772                 parms->link = nla_get_u32(data[IFLA_VTI_LINK]);
 773
 774         if (data[IFLA_VTI_IKEY])
 775                 parms->i_key = nla_get_be32(data[IFLA_VTI_IKEY]);
 776
 777         if (data[IFLA_VTI_OKEY])
 778                 parms->o_key = nla_get_be32(data[IFLA_VTI_OKEY]);
 779
 780         if (data[IFLA_VTI_LOCAL])
 781                 parms->iph.saddr = nla_get_be32(data[IFLA_VTI_LOCAL]);
 782
 783         if (data[IFLA_VTI_REMOTE])
 784                 parms->iph.daddr = nla_get_be32(data[IFLA_VTI_REMOTE]);
 785
 786 }
 787
 788 static int vti_newlink(struct net *src_net, struct net_device *dev,
 789                        struct nlattr *tb[], struct nlattr *data[])
 790 {
 791         struct ip_tunnel *nt;
 792         struct net *net = dev_net(dev);
 793         struct vti_net *ipn = net_generic(net, vti_net_id);
 794         int mtu;
 795         int err;
 796
 797         nt = netdev_priv(dev);
 798         vti_netlink_parms(data, &nt->parms);
 799
 800         if (vti_tunnel_locate(net, &nt->parms, 0))
 801                 return -EEXIST;
 802
 803         mtu = vti_tunnel_bind_dev(dev);
 804         if (!tb[IFLA_MTU])
 805                 dev->mtu = mtu;
 806
 807         err = register_netdevice(dev);
 808         if (err)
 809                 goto out;
 810
 811         dev_hold(dev);
 812         vti_tunnel_link(ipn, nt);
 813
 814 out:
 815         return err;
 816 }
 817
 818 static int vti_changelink(struct net_device *dev, struct nlattr *tb[],
 819                           struct nlattr *data[])
 820 {
 821         struct ip_tunnel *t, *nt;
 822         struct net *net = dev_net(dev);
 823         struct vti_net *ipn = net_generic(net, vti_net_id);
 824         struct ip_tunnel_parm p;
 825         int mtu;
 826
 827         if (dev == ipn->fb_tunnel_dev)
 828                 return -EINVAL;
 829
 830         nt = netdev_priv(dev);
 831         vti_netlink_parms(data, &p);
 832
 833         t = vti_tunnel_locate(net, &p, 0);
 834
 835         if (t) {
 836                 if (t->dev != dev)
 837                         return -EEXIST;
 838         } else {
 839                 t = nt;
 840
 841                 vti_tunnel_unlink(ipn, t);
 842                 t->parms.iph.saddr = p.iph.saddr;
 843                 t->parms.iph.daddr = p.iph.daddr;
 844                 t->parms.i_key = p.i_key;
 845                 t->parms.o_key = p.o_key;
 846                 if (dev->type != ARPHRD_ETHER) {
 847                         memcpy(dev->dev_addr, &p.iph.saddr, 4);
 848                         memcpy(dev->broadcast, &p.iph.daddr, 4);
 849                 }
 850                 vti_tunnel_link(ipn, t);
 851                 netdev_state_change(dev);
 852         }
 853
 854         if (t->parms.link != p.link) {
 855                 t->parms.link = p.link;
 856                 mtu = vti_tunnel_bind_dev(dev);
 857                 if (!tb[IFLA_MTU])
 858                         dev->mtu = mtu;
 859                 netdev_state_change(dev);
 860         }
 861
 862         return 0;
 863 }
 864
 865 static size_t vti_get_size(const struct net_device *dev)
 866 {
 867         return
 868                 /* IFLA_VTI_LINK */
 869                 nla_total_size(4) +
 870                 /* IFLA_VTI_IKEY */
 871                 nla_total_size(4) +
 872                 /* IFLA_VTI_OKEY */
 873                 nla_total_size(4) +
 874                 /* IFLA_VTI_LOCAL */
 875                 nla_total_size(4) +
 876                 /* IFLA_VTI_REMOTE */
 877                 nla_total_size(4) +
 878                 0;
 879 }
 880
 881 static int vti_fill_info(struct sk_buff *skb, const struct net_device *dev)
 882 {
 883         struct ip_tunnel *t = netdev_priv(dev);
 884         struct ip_tunnel_parm *p = &t->parms;
 885
 886         nla_put_u32(skb, IFLA_VTI_LINK, p->link);
 887         nla_put_be32(skb, IFLA_VTI_IKEY, p->i_key);
 888         nla_put_be32(skb, IFLA_VTI_OKEY, p->o_key);
 889         nla_put_be32(skb, IFLA_VTI_LOCAL, p->iph.saddr);
 890         nla_put_be32(skb, IFLA_VTI_REMOTE, p->iph.daddr);
 891
 892         return 0;
 893 }
 894
 895 static const struct nla_policy vti_policy[IFLA_VTI_MAX + 1] = {
 896         [IFLA_VTI_LINK]         = { .type = NLA_U32 },
 897         [IFLA_VTI_IKEY]         = { .type = NLA_U32 },
 898         [IFLA_VTI_OKEY]         = { .type = NLA_U32 },
 899         [IFLA_VTI_LOCAL]        = { .len = FIELD_SIZEOF(struct iphdr, saddr) },
 900         [IFLA_VTI_REMOTE]       = { .len = FIELD_SIZEOF(struct iphdr, daddr) },
 901 };
 902
 903 static struct rtnl_link_ops vti_link_ops __read_mostly = {
 904         .kind           = "vti",
 905         .maxtype        = IFLA_VTI_MAX,
 906         .policy         = vti_policy,
 907         .priv_size      = sizeof(struct ip_tunnel),
 908         .setup          = vti_tunnel_setup,
 909         .validate       = vti_tunnel_validate,
 910         .newlink        = vti_newlink,
 911         .changelink     = vti_changelink,
 912         .get_size       = vti_get_size,
 913         .fill_info      = vti_fill_info,
 914 };
 915
 916 static int __init vti_init(void)
 917 {
 918         int err;
 919
 920         pr_info("IPv4 over IPSec tunneling driver\n");
 921
 922         err = register_pernet_device(&vti_net_ops);
 923         if (err < 0)
 924                 return err;
 925         err = xfrm4_mode_tunnel_input_register(&vti_handler);
 926         if (err < 0) {
 927                 unregister_pernet_device(&vti_net_ops);
 928                 pr_info(KERN_INFO "vti init: can't register tunnel\n");
 929         }
 930
 931         err = rtnl_link_register(&vti_link_ops);
 932         if (err < 0)
 933                 goto rtnl_link_failed;
 934
 935         return err;
 936
 937 rtnl_link_failed:
 938         xfrm4_mode_tunnel_input_deregister(&vti_handler);
 939         unregister_pernet_device(&vti_net_ops);
 940         return err;
 941 }
 942
 943 static void __exit vti_fini(void)
 944 {
 945         rtnl_link_unregister(&vti_link_ops);
 946         if (xfrm4_mode_tunnel_input_deregister(&vti_handler))
 947                 pr_info("vti close: can't deregister tunnel\n");
 948
 949         unregister_pernet_device(&vti_net_ops);
 950 }
 951
 952 module_init(vti_init);
 953 module_exit(vti_fini);
 954 MODULE_LICENSE("GPL");
 955 MODULE_ALIAS_RTNL_LINK("vti");
 956 MODULE_ALIAS_NETDEV("ip_vti0");