net/ipv4/ipip.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *      Linux NET3:     IP/IP protocol decoder.
   4  *
   5  *      Authors:
   6  *              Sam Lantinga (slouken@cs.ucdavis.edu)  02/01/95
   7  *
   8  *      Fixes:
   9  *              Alan Cox        :       Merged and made usable non modular (its so tiny its silly as
  10  *                                      a module taking up 2 pages).
  11  *              Alan Cox        :       Fixed bug with 1.3.18 and IPIP not working (now needs to set skb->h.iph)
  12  *                                      to keep ip_forward happy.
  13  *              Alan Cox        :       More fixes for 1.3.21, and firewall fix. Maybe this will work soon 8).
  14  *              Kai Schulte     :       Fixed #defines for IP_FIREWALL->FIREWALL
  15  *              David Woodhouse :       Perform some basic ICMP handling.
  16  *                                      IPIP Routing without decapsulation.
  17  *              Carlos Picoto   :       GRE over IP support
  18  *              Alexey Kuznetsov:       Reworked. Really, now it is truncated version of ipv4/ip_gre.c.
  19  *                                      I do not want to merge them together.
  20  */
  21
  22 /* tunnel.c: an IP tunnel driver
  23
  24         The purpose of this driver is to provide an IP tunnel through
  25         which you can tunnel network traffic transparently across subnets.
  26
  27         This was written by looking at Nick Holloway's dummy driver
  28         Thanks for the great code!
  29
  30                 -Sam Lantinga   (slouken@cs.ucdavis.edu)  02/01/95
  31
  32         Minor tweaks:
  33                 Cleaned up the code a little and added some pre-1.3.0 tweaks.
  34                 dev->hard_header/hard_header_len changed to use no headers.
  35                 Comments/bracketing tweaked.
  36                 Made the tunnels use dev->name not tunnel: when error reporting.
  37                 Added tx_dropped stat
  38
  39                 -Alan Cox       (alan@lxorguk.ukuu.org.uk) 21 March 95
  40
  41         Reworked:
  42                 Changed to tunnel to destination gateway in addition to the
  43                         tunnel's pointopoint address
  44                 Almost completely rewritten
  45                 Note:  There is currently no firewall or ICMP handling done.
  46
  47                 -Sam Lantinga   (slouken@cs.ucdavis.edu) 02/13/96
  48
  49 */
  50
  51 /* Things I wish I had known when writing the tunnel driver:
  52
  53         When the tunnel_xmit() function is called, the skb contains the
  54         packet to be sent (plus a great deal of extra info), and dev
  55         contains the tunnel device that _we_ are.
  56
  57         When we are passed a packet, we are expected to fill in the
  58         source address with our source IP address.
  59
  60         What is the proper way to allocate, copy and free a buffer?
  61         After you allocate it, it is a "0 length" chunk of memory
  62         starting at zero.  If you want to add headers to the buffer
  63         later, you'll have to call "skb_reserve(skb, amount)" with
  64         the amount of memory you want reserved.  Then, you call
  65         "skb_put(skb, amount)" with the amount of space you want in
  66         the buffer.  skb_put() returns a pointer to the top (#0) of
  67         that buffer.  skb->len is set to the amount of space you have
  68         "allocated" with skb_put().  You can then write up to skb->len
  69         bytes to that buffer.  If you need more, you can call skb_put()
  70         again with the additional amount of space you need.  You can
  71         find out how much more space you can allocate by calling
  72         "skb_tailroom(skb)".
  73         Now, to add header space, call "skb_push(skb, header_len)".
  74         This creates space at the beginning of the buffer and returns
  75         a pointer to this new space.  If later you need to strip a
  76         header from a buffer, call "skb_pull(skb, header_len)".
  77         skb_headroom() will return how much space is left at the top
  78         of the buffer (before the main data).  Remember, this headroom
  79         space must be reserved before the skb_put() function is called.
  80         */
  81
  82 /*
  83    This version of net/ipv4/ipip.c is cloned of net/ipv4/ip_gre.c
  84
  85    For comments look at net/ipv4/ip_gre.c --ANK
  86  */
  87
  88
  89 #include <linux/capability.h>
  90 #include <linux/module.h>
  91 #include <linux/types.h>
  92 #include <linux/kernel.h>
  93 #include <linux/slab.h>
  94 #include <linux/uaccess.h>
  95 #include <linux/skbuff.h>
  96 #include <linux/netdevice.h>
  97 #include <linux/in.h>
  98 #include <linux/tcp.h>
  99 #include <linux/udp.h>
 100 #include <linux/if_arp.h>
 101 #include <linux/init.h>
 102 #include <linux/netfilter_ipv4.h>
 103 #include <linux/if_ether.h>
 104
 105 #include <net/sock.h>
 106 #include <net/ip.h>
 107 #include <net/icmp.h>
 108 #include <net/ip_tunnels.h>
 109 #include <net/inet_ecn.h>
 110 #include <net/xfrm.h>
 111 #include <net/net_namespace.h>
 112 #include <net/netns/generic.h>
 113 #include <net/dst_metadata.h>
 114
 115 static bool log_ecn_error = true;
 116 module_param(log_ecn_error, bool, 0644);
 117 MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");
 118
 119 static unsigned int ipip_net_id __read_mostly;
 120
 121 static int ipip_tunnel_init(struct net_device *dev);
 122 static struct rtnl_link_ops ipip_link_ops __read_mostly;
 123
 124 static int ipip_err(struct sk_buff *skb, u32 info)
 125 {
 126         /* All the routers (except for Linux) return only
 127          * 8 bytes of packet payload. It means, that precise relaying of
 128          * ICMP in the real Internet is absolutely infeasible.
 129          */
 130         struct net *net = dev_net(skb->dev);
 131         struct ip_tunnel_net *itn = net_generic(net, ipip_net_id);
 132         const struct iphdr *iph = (const struct iphdr *)skb->data;
 133         const int type = icmp_hdr(skb)->type;
 134         const int code = icmp_hdr(skb)->code;
 135         struct ip_tunnel *t;
 136         int err = 0;
 137
 138         t = ip_tunnel_lookup(itn, skb->dev->ifindex, TUNNEL_NO_KEY,
 139                              iph->daddr, iph->saddr, 0);
 140         if (!t) {
 141                 err = -ENOENT;
 142                 goto out;
 143         }
 144
 145         switch (type) {
 146         case ICMP_DEST_UNREACH:
 147                 switch (code) {
 148                 case ICMP_SR_FAILED:
 149                         /* Impossible event. */
 150                         goto out;
 151                 default:
 152                         /* All others are translated to HOST_UNREACH.
 153                          * rfc2003 contains "deep thoughts" about NET_UNREACH,
 154                          * I believe they are just ether pollution. --ANK
 155                          */
 156                         break;
 157                 }
 158                 break;
 159
 160         case ICMP_TIME_EXCEEDED:
 161                 if (code != ICMP_EXC_TTL)
 162                         goto out;
 163                 break;
 164
 165         case ICMP_REDIRECT:
 166                 break;
 167
 168         default:
 169                 goto out;
 170         }
 171
 172         if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) {
 173                 ipv4_update_pmtu(skb, net, info, t->parms.link, iph->protocol);
 174                 goto out;
 175         }
 176
 177         if (type == ICMP_REDIRECT) {
 178                 ipv4_redirect(skb, net, t->parms.link, iph->protocol);
 179                 goto out;
 180         }
 181
 182         if (t->parms.iph.daddr == 0) {
 183                 err = -ENOENT;
 184                 goto out;
 185         }
 186
 187         if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
 188                 goto out;
 189
 190         if (time_before(jiffies, t->err_time + IPTUNNEL_ERR_TIMEO))
 191                 t->err_count++;
 192         else
 193                 t->err_count = 1;
 194         t->err_time = jiffies;
 195
 196 out:
 197         return err;
 198 }
 199
 200 static const struct tnl_ptk_info ipip_tpi = {
 201         /* no tunnel info required for ipip. */
 202         .proto = htons(ETH_P_IP),
 203 };
 204
 205 #if IS_ENABLED(CONFIG_MPLS)
 206 static const struct tnl_ptk_info mplsip_tpi = {
 207         /* no tunnel info required for mplsip. */
 208         .proto = htons(ETH_P_MPLS_UC),
 209 };
 210 #endif
 211
 212 static int ipip_tunnel_rcv(struct sk_buff *skb, u8 ipproto)
 213 {
 214         struct net *net = dev_net(skb->dev);
 215         struct ip_tunnel_net *itn = net_generic(net, ipip_net_id);
 216         struct metadata_dst *tun_dst = NULL;
 217         struct ip_tunnel *tunnel;
 218         const struct iphdr *iph;
 219
 220         iph = ip_hdr(skb);
 221         tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, TUNNEL_NO_KEY,
 222                         iph->saddr, iph->daddr, 0);
 223         if (tunnel) {
 224                 const struct tnl_ptk_info *tpi;
 225
 226                 if (tunnel->parms.iph.protocol != ipproto &&
 227                     tunnel->parms.iph.protocol != 0)
 228                         goto drop;
 229
 230                 if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb))
 231                         goto drop;
 232 #if IS_ENABLED(CONFIG_MPLS)
 233                 if (ipproto == IPPROTO_MPLS)
 234                         tpi = &mplsip_tpi;
 235                 else
 236 #endif
 237                         tpi = &ipip_tpi;
 238                 if (iptunnel_pull_header(skb, 0, tpi->proto, false))
 239                         goto drop;
 240                 if (tunnel->collect_md) {
 241                         tun_dst = ip_tun_rx_dst(skb, 0, 0, 0);
 242                         if (!tun_dst)
 243                                 return 0;
 244                 }
 245                 skb_reset_mac_header(skb);
 246
 247                 return ip_tunnel_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
 248         }
 249
 250         return -1;
 251
 252 drop:
 253         kfree_skb(skb);
 254         return 0;
 255 }
 256
 257 static int ipip_rcv(struct sk_buff *skb)
 258 {
 259         return ipip_tunnel_rcv(skb, IPPROTO_IPIP);
 260 }
 261
 262 #if IS_ENABLED(CONFIG_MPLS)
 263 static int mplsip_rcv(struct sk_buff *skb)
 264 {
 265         return ipip_tunnel_rcv(skb, IPPROTO_MPLS);
 266 }
 267 #endif
 268
 269 /*
 270  *      This function assumes it is being called from dev_queue_xmit()
 271  *      and that skb is filled properly by that function.
 272  */
 273 static netdev_tx_t ipip_tunnel_xmit(struct sk_buff *skb,
 274                                     struct net_device *dev)
 275 {
 276         struct ip_tunnel *tunnel = netdev_priv(dev);
 277         const struct iphdr  *tiph = &tunnel->parms.iph;
 278         u8 ipproto;
 279
 280         if (!pskb_inet_may_pull(skb))
 281                 goto tx_error;
 282
 283         switch (skb->protocol) {
 284         case htons(ETH_P_IP):
 285                 ipproto = IPPROTO_IPIP;
 286                 break;
 287 #if IS_ENABLED(CONFIG_MPLS)
 288         case htons(ETH_P_MPLS_UC):
 289                 ipproto = IPPROTO_MPLS;
 290                 break;
 291 #endif
 292         default:
 293                 goto tx_error;
 294         }
 295
 296         if (tiph->protocol != ipproto && tiph->protocol != 0)
 297                 goto tx_error;
 298
 299         if (iptunnel_handle_offloads(skb, SKB_GSO_IPXIP4))
 300                 goto tx_error;
 301
 302         skb_set_inner_ipproto(skb, ipproto);
 303
 304         if (tunnel->collect_md)
 305                 ip_md_tunnel_xmit(skb, dev, ipproto, 0);
 306         else
 307                 ip_tunnel_xmit(skb, dev, tiph, ipproto);
 308         return NETDEV_TX_OK;
 309
 310 tx_error:
 311         kfree_skb(skb);
 312
 313         dev->stats.tx_errors++;
 314         return NETDEV_TX_OK;
 315 }
 316
 317 static bool ipip_tunnel_ioctl_verify_protocol(u8 ipproto)
 318 {
 319         switch (ipproto) {
 320         case 0:
 321         case IPPROTO_IPIP:
 322 #if IS_ENABLED(CONFIG_MPLS)
 323         case IPPROTO_MPLS:
 324 #endif
 325                 return true;
 326         }
 327
 328         return false;
 329 }
 330
 331 static int
 332 ipip_tunnel_ctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd)
 333 {
 334         if (cmd == SIOCADDTUNNEL || cmd == SIOCCHGTUNNEL) {
 335                 if (p->iph.version != 4 ||
 336                     !ipip_tunnel_ioctl_verify_protocol(p->iph.protocol) ||
 337                     p->iph.ihl != 5 || (p->iph.frag_off & htons(~IP_DF)))
 338                         return -EINVAL;
 339         }
 340
 341         p->i_key = p->o_key = 0;
 342         p->i_flags = p->o_flags = 0;
 343         return ip_tunnel_ctl(dev, p, cmd);
 344 }
 345
 346 static const struct net_device_ops ipip_netdev_ops = {
 347         .ndo_init       = ipip_tunnel_init,
 348         .ndo_uninit     = ip_tunnel_uninit,
 349         .ndo_start_xmit = ipip_tunnel_xmit,
 350         .ndo_siocdevprivate = ip_tunnel_siocdevprivate,
 351         .ndo_change_mtu = ip_tunnel_change_mtu,
 352         .ndo_get_stats64 = dev_get_tstats64,
 353         .ndo_get_iflink = ip_tunnel_get_iflink,
 354         .ndo_tunnel_ctl = ipip_tunnel_ctl,
 355 };
 356
 357 #define IPIP_FEATURES (NETIF_F_SG |             \
 358                        NETIF_F_FRAGLIST |       \
 359                        NETIF_F_HIGHDMA |        \
 360                        NETIF_F_GSO_SOFTWARE |   \
 361                        NETIF_F_HW_CSUM)
 362
 363 static void ipip_tunnel_setup(struct net_device *dev)
 364 {
 365         dev->netdev_ops         = &ipip_netdev_ops;
 366         dev->header_ops         = &ip_tunnel_header_ops;
 367
 368         dev->type               = ARPHRD_TUNNEL;
 369         dev->flags              = IFF_NOARP;
 370         dev->addr_len           = 4;
 371         dev->features           |= NETIF_F_LLTX;
 372         netif_keep_dst(dev);
 373
 374         dev->features           |= IPIP_FEATURES;
 375         dev->hw_features        |= IPIP_FEATURES;
 376         ip_tunnel_setup(dev, ipip_net_id);
 377 }
 378
 379 static int ipip_tunnel_init(struct net_device *dev)
 380 {
 381         struct ip_tunnel *tunnel = netdev_priv(dev);
 382
 383         memcpy(dev->dev_addr, &tunnel->parms.iph.saddr, 4);
 384         memcpy(dev->broadcast, &tunnel->parms.iph.daddr, 4);
 385
 386         tunnel->tun_hlen = 0;
 387         tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen;
 388         return ip_tunnel_init(dev);
 389 }
 390
 391 static int ipip_tunnel_validate(struct nlattr *tb[], struct nlattr *data[],
 392                                 struct netlink_ext_ack *extack)
 393 {
 394         u8 proto;
 395
 396         if (!data || !data[IFLA_IPTUN_PROTO])
 397                 return 0;
 398
 399         proto = nla_get_u8(data[IFLA_IPTUN_PROTO]);
 400         if (proto != IPPROTO_IPIP && proto != IPPROTO_MPLS && proto != 0)
 401                 return -EINVAL;
 402
 403         return 0;
 404 }
 405
 406 static void ipip_netlink_parms(struct nlattr *data[],
 407                                struct ip_tunnel_parm *parms, bool *collect_md,
 408                                __u32 *fwmark)
 409 {
 410         memset(parms, 0, sizeof(*parms));
 411
 412         parms->iph.version = 4;
 413         parms->iph.protocol = IPPROTO_IPIP;
 414         parms->iph.ihl = 5;
 415         *collect_md = false;
 416
 417         if (!data)
 418                 return;
 419
 420         if (data[IFLA_IPTUN_LINK])
 421                 parms->link = nla_get_u32(data[IFLA_IPTUN_LINK]);
 422
 423         if (data[IFLA_IPTUN_LOCAL])
 424                 parms->iph.saddr = nla_get_in_addr(data[IFLA_IPTUN_LOCAL]);
 425
 426         if (data[IFLA_IPTUN_REMOTE])
 427                 parms->iph.daddr = nla_get_in_addr(data[IFLA_IPTUN_REMOTE]);
 428
 429         if (data[IFLA_IPTUN_TTL]) {
 430                 parms->iph.ttl = nla_get_u8(data[IFLA_IPTUN_TTL]);
 431                 if (parms->iph.ttl)
 432                         parms->iph.frag_off = htons(IP_DF);
 433         }
 434
 435         if (data[IFLA_IPTUN_TOS])
 436                 parms->iph.tos = nla_get_u8(data[IFLA_IPTUN_TOS]);
 437
 438         if (data[IFLA_IPTUN_PROTO])
 439                 parms->iph.protocol = nla_get_u8(data[IFLA_IPTUN_PROTO]);
 440
 441         if (!data[IFLA_IPTUN_PMTUDISC] || nla_get_u8(data[IFLA_IPTUN_PMTUDISC]))
 442                 parms->iph.frag_off = htons(IP_DF);
 443
 444         if (data[IFLA_IPTUN_COLLECT_METADATA])
 445                 *collect_md = true;
 446
 447         if (data[IFLA_IPTUN_FWMARK])
 448                 *fwmark = nla_get_u32(data[IFLA_IPTUN_FWMARK]);
 449 }
 450
 451 /* This function returns true when ENCAP attributes are present in the nl msg */
 452 static bool ipip_netlink_encap_parms(struct nlattr *data[],
 453                                      struct ip_tunnel_encap *ipencap)
 454 {
 455         bool ret = false;
 456
 457         memset(ipencap, 0, sizeof(*ipencap));
 458
 459         if (!data)
 460                 return ret;
 461
 462         if (data[IFLA_IPTUN_ENCAP_TYPE]) {
 463                 ret = true;
 464                 ipencap->type = nla_get_u16(data[IFLA_IPTUN_ENCAP_TYPE]);
 465         }
 466
 467         if (data[IFLA_IPTUN_ENCAP_FLAGS]) {
 468                 ret = true;
 469                 ipencap->flags = nla_get_u16(data[IFLA_IPTUN_ENCAP_FLAGS]);
 470         }
 471
 472         if (data[IFLA_IPTUN_ENCAP_SPORT]) {
 473                 ret = true;
 474                 ipencap->sport = nla_get_be16(data[IFLA_IPTUN_ENCAP_SPORT]);
 475         }
 476
 477         if (data[IFLA_IPTUN_ENCAP_DPORT]) {
 478                 ret = true;
 479                 ipencap->dport = nla_get_be16(data[IFLA_IPTUN_ENCAP_DPORT]);
 480         }
 481
 482         return ret;
 483 }
 484
 485 static int ipip_newlink(struct net *src_net, struct net_device *dev,
 486                         struct nlattr *tb[], struct nlattr *data[],
 487                         struct netlink_ext_ack *extack)
 488 {
 489         struct ip_tunnel *t = netdev_priv(dev);
 490         struct ip_tunnel_parm p;
 491         struct ip_tunnel_encap ipencap;
 492         __u32 fwmark = 0;
 493
 494         if (ipip_netlink_encap_parms(data, &ipencap)) {
 495                 int err = ip_tunnel_encap_setup(t, &ipencap);
 496
 497                 if (err < 0)
 498                         return err;
 499         }
 500
 501         ipip_netlink_parms(data, &p, &t->collect_md, &fwmark);
 502         return ip_tunnel_newlink(dev, tb, &p, fwmark);
 503 }
 504
 505 static int ipip_changelink(struct net_device *dev, struct nlattr *tb[],
 506                            struct nlattr *data[],
 507                            struct netlink_ext_ack *extack)
 508 {
 509         struct ip_tunnel *t = netdev_priv(dev);
 510         struct ip_tunnel_parm p;
 511         struct ip_tunnel_encap ipencap;
 512         bool collect_md;
 513         __u32 fwmark = t->fwmark;
 514
 515         if (ipip_netlink_encap_parms(data, &ipencap)) {
 516                 int err = ip_tunnel_encap_setup(t, &ipencap);
 517
 518                 if (err < 0)
 519                         return err;
 520         }
 521
 522         ipip_netlink_parms(data, &p, &collect_md, &fwmark);
 523         if (collect_md)
 524                 return -EINVAL;
 525
 526         if (((dev->flags & IFF_POINTOPOINT) && !p.iph.daddr) ||
 527             (!(dev->flags & IFF_POINTOPOINT) && p.iph.daddr))
 528                 return -EINVAL;
 529
 530         return ip_tunnel_changelink(dev, tb, &p, fwmark);
 531 }
 532
 533 static size_t ipip_get_size(const struct net_device *dev)
 534 {
 535         return
 536                 /* IFLA_IPTUN_LINK */
 537                 nla_total_size(4) +
 538                 /* IFLA_IPTUN_LOCAL */
 539                 nla_total_size(4) +
 540                 /* IFLA_IPTUN_REMOTE */
 541                 nla_total_size(4) +
 542                 /* IFLA_IPTUN_TTL */
 543                 nla_total_size(1) +
 544                 /* IFLA_IPTUN_TOS */
 545                 nla_total_size(1) +
 546                 /* IFLA_IPTUN_PROTO */
 547                 nla_total_size(1) +
 548                 /* IFLA_IPTUN_PMTUDISC */
 549                 nla_total_size(1) +
 550                 /* IFLA_IPTUN_ENCAP_TYPE */
 551                 nla_total_size(2) +
 552                 /* IFLA_IPTUN_ENCAP_FLAGS */
 553                 nla_total_size(2) +
 554                 /* IFLA_IPTUN_ENCAP_SPORT */
 555                 nla_total_size(2) +
 556                 /* IFLA_IPTUN_ENCAP_DPORT */
 557                 nla_total_size(2) +
 558                 /* IFLA_IPTUN_COLLECT_METADATA */
 559                 nla_total_size(0) +
 560                 /* IFLA_IPTUN_FWMARK */
 561                 nla_total_size(4) +
 562                 0;
 563 }
 564
 565 static int ipip_fill_info(struct sk_buff *skb, const struct net_device *dev)
 566 {
 567         struct ip_tunnel *tunnel = netdev_priv(dev);
 568         struct ip_tunnel_parm *parm = &tunnel->parms;
 569
 570         if (nla_put_u32(skb, IFLA_IPTUN_LINK, parm->link) ||
 571             nla_put_in_addr(skb, IFLA_IPTUN_LOCAL, parm->iph.saddr) ||
 572             nla_put_in_addr(skb, IFLA_IPTUN_REMOTE, parm->iph.daddr) ||
 573             nla_put_u8(skb, IFLA_IPTUN_TTL, parm->iph.ttl) ||
 574             nla_put_u8(skb, IFLA_IPTUN_TOS, parm->iph.tos) ||
 575             nla_put_u8(skb, IFLA_IPTUN_PROTO, parm->iph.protocol) ||
 576             nla_put_u8(skb, IFLA_IPTUN_PMTUDISC,
 577                        !!(parm->iph.frag_off & htons(IP_DF))) ||
 578             nla_put_u32(skb, IFLA_IPTUN_FWMARK, tunnel->fwmark))
 579                 goto nla_put_failure;
 580
 581         if (nla_put_u16(skb, IFLA_IPTUN_ENCAP_TYPE,
 582                         tunnel->encap.type) ||
 583             nla_put_be16(skb, IFLA_IPTUN_ENCAP_SPORT,
 584                          tunnel->encap.sport) ||
 585             nla_put_be16(skb, IFLA_IPTUN_ENCAP_DPORT,
 586                          tunnel->encap.dport) ||
 587             nla_put_u16(skb, IFLA_IPTUN_ENCAP_FLAGS,
 588                         tunnel->encap.flags))
 589                 goto nla_put_failure;
 590
 591         if (tunnel->collect_md)
 592                 if (nla_put_flag(skb, IFLA_IPTUN_COLLECT_METADATA))
 593                         goto nla_put_failure;
 594         return 0;
 595
 596 nla_put_failure:
 597         return -EMSGSIZE;
 598 }
 599
 600 static const struct nla_policy ipip_policy[IFLA_IPTUN_MAX + 1] = {
 601         [IFLA_IPTUN_LINK]               = { .type = NLA_U32 },
 602         [IFLA_IPTUN_LOCAL]              = { .type = NLA_U32 },
 603         [IFLA_IPTUN_REMOTE]             = { .type = NLA_U32 },
 604         [IFLA_IPTUN_TTL]                = { .type = NLA_U8 },
 605         [IFLA_IPTUN_TOS]                = { .type = NLA_U8 },
 606         [IFLA_IPTUN_PROTO]              = { .type = NLA_U8 },
 607         [IFLA_IPTUN_PMTUDISC]           = { .type = NLA_U8 },
 608         [IFLA_IPTUN_ENCAP_TYPE]         = { .type = NLA_U16 },
 609         [IFLA_IPTUN_ENCAP_FLAGS]        = { .type = NLA_U16 },
 610         [IFLA_IPTUN_ENCAP_SPORT]        = { .type = NLA_U16 },
 611         [IFLA_IPTUN_ENCAP_DPORT]        = { .type = NLA_U16 },
 612         [IFLA_IPTUN_COLLECT_METADATA]   = { .type = NLA_FLAG },
 613         [IFLA_IPTUN_FWMARK]             = { .type = NLA_U32 },
 614 };
 615
 616 static struct rtnl_link_ops ipip_link_ops __read_mostly = {
 617         .kind           = "ipip",
 618         .maxtype        = IFLA_IPTUN_MAX,
 619         .policy         = ipip_policy,
 620         .priv_size      = sizeof(struct ip_tunnel),
 621         .setup          = ipip_tunnel_setup,
 622         .validate       = ipip_tunnel_validate,
 623         .newlink        = ipip_newlink,
 624         .changelink     = ipip_changelink,
 625         .dellink        = ip_tunnel_dellink,
 626         .get_size       = ipip_get_size,
 627         .fill_info      = ipip_fill_info,
 628         .get_link_net   = ip_tunnel_get_link_net,
 629 };
 630
 631 static struct xfrm_tunnel ipip_handler __read_mostly = {
 632         .handler        =       ipip_rcv,
 633         .err_handler    =       ipip_err,
 634         .priority       =       1,
 635 };
 636
 637 #if IS_ENABLED(CONFIG_MPLS)
 638 static struct xfrm_tunnel mplsip_handler __read_mostly = {
 639         .handler        =       mplsip_rcv,
 640         .err_handler    =       ipip_err,
 641         .priority       =       1,
 642 };
 643 #endif
 644
 645 static int __net_init ipip_init_net(struct net *net)
 646 {
 647         return ip_tunnel_init_net(net, ipip_net_id, &ipip_link_ops, "tunl0");
 648 }
 649
 650 static void __net_exit ipip_exit_batch_net(struct list_head *list_net)
 651 {
 652         ip_tunnel_delete_nets(list_net, ipip_net_id, &ipip_link_ops);
 653 }
 654
 655 static struct pernet_operations ipip_net_ops = {
 656         .init = ipip_init_net,
 657         .exit_batch = ipip_exit_batch_net,
 658         .id   = &ipip_net_id,
 659         .size = sizeof(struct ip_tunnel_net),
 660 };
 661
 662 static int __init ipip_init(void)
 663 {
 664         int err;
 665
 666         pr_info("ipip: IPv4 and MPLS over IPv4 tunneling driver\n");
 667
 668         err = register_pernet_device(&ipip_net_ops);
 669         if (err < 0)
 670                 return err;
 671         err = xfrm4_tunnel_register(&ipip_handler, AF_INET);
 672         if (err < 0) {
 673                 pr_info("%s: can't register tunnel\n", __func__);
 674                 goto xfrm_tunnel_ipip_failed;
 675         }
 676 #if IS_ENABLED(CONFIG_MPLS)
 677         err = xfrm4_tunnel_register(&mplsip_handler, AF_MPLS);
 678         if (err < 0) {
 679                 pr_info("%s: can't register tunnel\n", __func__);
 680                 goto xfrm_tunnel_mplsip_failed;
 681         }
 682 #endif
 683         err = rtnl_link_register(&ipip_link_ops);
 684         if (err < 0)
 685                 goto rtnl_link_failed;
 686
 687 out:
 688         return err;
 689
 690 rtnl_link_failed:
 691 #if IS_ENABLED(CONFIG_MPLS)
 692         xfrm4_tunnel_deregister(&mplsip_handler, AF_MPLS);
 693 xfrm_tunnel_mplsip_failed:
 694
 695 #endif
 696         xfrm4_tunnel_deregister(&ipip_handler, AF_INET);
 697 xfrm_tunnel_ipip_failed:
 698         unregister_pernet_device(&ipip_net_ops);
 699         goto out;
 700 }
 701
 702 static void __exit ipip_fini(void)
 703 {
 704         rtnl_link_unregister(&ipip_link_ops);
 705         if (xfrm4_tunnel_deregister(&ipip_handler, AF_INET))
 706                 pr_info("%s: can't deregister tunnel\n", __func__);
 707 #if IS_ENABLED(CONFIG_MPLS)
 708         if (xfrm4_tunnel_deregister(&mplsip_handler, AF_MPLS))
 709                 pr_info("%s: can't deregister tunnel\n", __func__);
 710 #endif
 711         unregister_pernet_device(&ipip_net_ops);
 712 }
 713
 714 module_init(ipip_init);
 715 module_exit(ipip_fini);
 716 MODULE_LICENSE("GPL");
 717 MODULE_ALIAS_RTNL_LINK("ipip");
 718 MODULE_ALIAS_NETDEV("tunl0");