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 IP_TUNNEL_DECLARE_FLAGS(flags) = { }; 134 const int type = icmp_hdr(skb)->type; 135 const int code = icmp_hdr(skb)->code; 136 struct ip_tunnel *t; 137 int err = 0; 138 139 __set_bit(IP_TUNNEL_NO_KEY_BIT, flags); 140 141 t = ip_tunnel_lookup(itn, skb->dev->ifindex, flags, iph->daddr, 142 iph->saddr, 0); 143 if (!t) { 144 err = -ENOENT; 145 goto out; 146 } 147 148 switch (type) { 149 case ICMP_DEST_UNREACH: 150 switch (code) { 151 case ICMP_SR_FAILED: 152 /* Impossible event. */ 153 goto out; 154 default: 155 /* All others are translated to HOST_UNREACH. 156 * rfc2003 contains "deep thoughts" about NET_UNREACH, 157 * I believe they are just ether pollution. --ANK 158 */ 159 break; 160 } 161 break; 162 163 case ICMP_TIME_EXCEEDED: 164 if (code != ICMP_EXC_TTL) 165 goto out; 166 break; 167 168 case ICMP_REDIRECT: 169 break; 170 171 default: 172 goto out; 173 } 174 175 if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) { 176 ipv4_update_pmtu(skb, net, info, t->parms.link, iph->protocol); 177 goto out; 178 } 179 180 if (type == ICMP_REDIRECT) { 181 ipv4_redirect(skb, net, t->parms.link, iph->protocol); 182 goto out; 183 } 184 185 if (t->parms.iph.daddr == 0) { 186 err = -ENOENT; 187 goto out; 188 } 189 190 if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED) 191 goto out; 192 193 if (time_before(jiffies, t->err_time + IPTUNNEL_ERR_TIMEO)) 194 t->err_count++; 195 else 196 t->err_count = 1; 197 t->err_time = jiffies; 198 199 out: 200 return err; 201 } 202 203 static const struct tnl_ptk_info ipip_tpi = { 204 /* no tunnel info required for ipip. */ 205 .proto = htons(ETH_P_IP), 206 }; 207 208 #if IS_ENABLED(CONFIG_MPLS) 209 static const struct tnl_ptk_info mplsip_tpi = { 210 /* no tunnel info required for mplsip. */ 211 .proto = htons(ETH_P_MPLS_UC), 212 }; 213 #endif 214 215 static int ipip_tunnel_rcv(struct sk_buff *skb, u8 ipproto) 216 { 217 struct net *net = dev_net(skb->dev); 218 struct ip_tunnel_net *itn = net_generic(net, ipip_net_id); 219 IP_TUNNEL_DECLARE_FLAGS(flags) = { }; 220 struct metadata_dst *tun_dst = NULL; 221 struct ip_tunnel *tunnel; 222 const struct iphdr *iph; 223 224 __set_bit(IP_TUNNEL_NO_KEY_BIT, flags); 225 226 iph = ip_hdr(skb); 227 tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, flags, iph->saddr, 228 iph->daddr, 0); 229 if (tunnel) { 230 const struct tnl_ptk_info *tpi; 231 232 if (tunnel->parms.iph.protocol != ipproto && 233 tunnel->parms.iph.protocol != 0) 234 goto drop; 235 236 if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) 237 goto drop; 238 #if IS_ENABLED(CONFIG_MPLS) 239 if (ipproto == IPPROTO_MPLS) 240 tpi = &mplsip_tpi; 241 else 242 #endif 243 tpi = &ipip_tpi; 244 if (iptunnel_pull_header(skb, 0, tpi->proto, false)) 245 goto drop; 246 if (tunnel->collect_md) { 247 ip_tunnel_flags_zero(flags); 248 249 tun_dst = ip_tun_rx_dst(skb, flags, 0, 0); 250 if (!tun_dst) 251 return 0; 252 ip_tunnel_md_udp_encap(skb, &tun_dst->u.tun_info); 253 } 254 skb_reset_mac_header(skb); 255 256 return ip_tunnel_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error); 257 } 258 259 return -1; 260 261 drop: 262 kfree_skb(skb); 263 return 0; 264 } 265 266 static int ipip_rcv(struct sk_buff *skb) 267 { 268 return ipip_tunnel_rcv(skb, IPPROTO_IPIP); 269 } 270 271 #if IS_ENABLED(CONFIG_MPLS) 272 static int mplsip_rcv(struct sk_buff *skb) 273 { 274 return ipip_tunnel_rcv(skb, IPPROTO_MPLS); 275 } 276 #endif 277 278 /* 279 * This function assumes it is being called from dev_queue_xmit() 280 * and that skb is filled properly by that function. 281 */ 282 static netdev_tx_t ipip_tunnel_xmit(struct sk_buff *skb, 283 struct net_device *dev) 284 { 285 struct ip_tunnel *tunnel = netdev_priv(dev); 286 const struct iphdr *tiph = &tunnel->parms.iph; 287 u8 ipproto; 288 289 if (!pskb_inet_may_pull(skb)) 290 goto tx_error; 291 292 switch (skb->protocol) { 293 case htons(ETH_P_IP): 294 ipproto = IPPROTO_IPIP; 295 break; 296 #if IS_ENABLED(CONFIG_MPLS) 297 case htons(ETH_P_MPLS_UC): 298 ipproto = IPPROTO_MPLS; 299 break; 300 #endif 301 default: 302 goto tx_error; 303 } 304 305 if (tiph->protocol != ipproto && tiph->protocol != 0) 306 goto tx_error; 307 308 if (iptunnel_handle_offloads(skb, SKB_GSO_IPXIP4)) 309 goto tx_error; 310 311 skb_set_inner_ipproto(skb, ipproto); 312 313 if (tunnel->collect_md) 314 ip_md_tunnel_xmit(skb, dev, ipproto, 0); 315 else 316 ip_tunnel_xmit(skb, dev, tiph, ipproto); 317 return NETDEV_TX_OK; 318 319 tx_error: 320 kfree_skb(skb); 321 322 DEV_STATS_INC(dev, tx_errors); 323 return NETDEV_TX_OK; 324 } 325 326 static bool ipip_tunnel_ioctl_verify_protocol(u8 ipproto) 327 { 328 switch (ipproto) { 329 case 0: 330 case IPPROTO_IPIP: 331 #if IS_ENABLED(CONFIG_MPLS) 332 case IPPROTO_MPLS: 333 #endif 334 return true; 335 } 336 337 return false; 338 } 339 340 static int 341 ipip_tunnel_ctl(struct net_device *dev, struct ip_tunnel_parm_kern *p, int cmd) 342 { 343 if (cmd == SIOCADDTUNNEL || cmd == SIOCCHGTUNNEL) { 344 if (p->iph.version != 4 || 345 !ipip_tunnel_ioctl_verify_protocol(p->iph.protocol) || 346 p->iph.ihl != 5 || (p->iph.frag_off & htons(~IP_DF))) 347 return -EINVAL; 348 } 349 350 p->i_key = p->o_key = 0; 351 ip_tunnel_flags_zero(p->i_flags); 352 ip_tunnel_flags_zero(p->o_flags); 353 return ip_tunnel_ctl(dev, p, cmd); 354 } 355 356 static const struct net_device_ops ipip_netdev_ops = { 357 .ndo_init = ipip_tunnel_init, 358 .ndo_uninit = ip_tunnel_uninit, 359 .ndo_start_xmit = ipip_tunnel_xmit, 360 .ndo_siocdevprivate = ip_tunnel_siocdevprivate, 361 .ndo_change_mtu = ip_tunnel_change_mtu, 362 .ndo_get_stats64 = dev_get_tstats64, 363 .ndo_get_iflink = ip_tunnel_get_iflink, 364 .ndo_tunnel_ctl = ipip_tunnel_ctl, 365 }; 366 367 #define IPIP_FEATURES (NETIF_F_SG | \ 368 NETIF_F_FRAGLIST | \ 369 NETIF_F_HIGHDMA | \ 370 NETIF_F_GSO_SOFTWARE | \ 371 NETIF_F_HW_CSUM) 372 373 static void ipip_tunnel_setup(struct net_device *dev) 374 { 375 dev->netdev_ops = &ipip_netdev_ops; 376 dev->header_ops = &ip_tunnel_header_ops; 377 378 dev->type = ARPHRD_TUNNEL; 379 dev->flags = IFF_NOARP; 380 dev->addr_len = 4; 381 dev->features |= NETIF_F_LLTX; 382 netif_keep_dst(dev); 383 384 dev->features |= IPIP_FEATURES; 385 dev->hw_features |= IPIP_FEATURES; 386 ip_tunnel_setup(dev, ipip_net_id); 387 } 388 389 static int ipip_tunnel_init(struct net_device *dev) 390 { 391 struct ip_tunnel *tunnel = netdev_priv(dev); 392 393 __dev_addr_set(dev, &tunnel->parms.iph.saddr, 4); 394 memcpy(dev->broadcast, &tunnel->parms.iph.daddr, 4); 395 396 tunnel->tun_hlen = 0; 397 tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen; 398 return ip_tunnel_init(dev); 399 } 400 401 static int ipip_tunnel_validate(struct nlattr *tb[], struct nlattr *data[], 402 struct netlink_ext_ack *extack) 403 { 404 u8 proto; 405 406 if (!data || !data[IFLA_IPTUN_PROTO]) 407 return 0; 408 409 proto = nla_get_u8(data[IFLA_IPTUN_PROTO]); 410 if (proto != IPPROTO_IPIP && proto != IPPROTO_MPLS && proto != 0) 411 return -EINVAL; 412 413 return 0; 414 } 415 416 static void ipip_netlink_parms(struct nlattr *data[], 417 struct ip_tunnel_parm_kern *parms, 418 bool *collect_md, __u32 *fwmark) 419 { 420 memset(parms, 0, sizeof(*parms)); 421 422 parms->iph.version = 4; 423 parms->iph.protocol = IPPROTO_IPIP; 424 parms->iph.ihl = 5; 425 *collect_md = false; 426 427 if (!data) 428 return; 429 430 ip_tunnel_netlink_parms(data, parms); 431 432 if (data[IFLA_IPTUN_COLLECT_METADATA]) 433 *collect_md = true; 434 435 if (data[IFLA_IPTUN_FWMARK]) 436 *fwmark = nla_get_u32(data[IFLA_IPTUN_FWMARK]); 437 } 438 439 static int ipip_newlink(struct net *src_net, struct net_device *dev, 440 struct nlattr *tb[], struct nlattr *data[], 441 struct netlink_ext_ack *extack) 442 { 443 struct ip_tunnel *t = netdev_priv(dev); 444 struct ip_tunnel_encap ipencap; 445 struct ip_tunnel_parm_kern p; 446 __u32 fwmark = 0; 447 448 if (ip_tunnel_netlink_encap_parms(data, &ipencap)) { 449 int err = ip_tunnel_encap_setup(t, &ipencap); 450 451 if (err < 0) 452 return err; 453 } 454 455 ipip_netlink_parms(data, &p, &t->collect_md, &fwmark); 456 return ip_tunnel_newlink(dev, tb, &p, fwmark); 457 } 458 459 static int ipip_changelink(struct net_device *dev, struct nlattr *tb[], 460 struct nlattr *data[], 461 struct netlink_ext_ack *extack) 462 { 463 struct ip_tunnel *t = netdev_priv(dev); 464 struct ip_tunnel_encap ipencap; 465 struct ip_tunnel_parm_kern p; 466 bool collect_md; 467 __u32 fwmark = t->fwmark; 468 469 if (ip_tunnel_netlink_encap_parms(data, &ipencap)) { 470 int err = ip_tunnel_encap_setup(t, &ipencap); 471 472 if (err < 0) 473 return err; 474 } 475 476 ipip_netlink_parms(data, &p, &collect_md, &fwmark); 477 if (collect_md) 478 return -EINVAL; 479 480 if (((dev->flags & IFF_POINTOPOINT) && !p.iph.daddr) || 481 (!(dev->flags & IFF_POINTOPOINT) && p.iph.daddr)) 482 return -EINVAL; 483 484 return ip_tunnel_changelink(dev, tb, &p, fwmark); 485 } 486 487 static size_t ipip_get_size(const struct net_device *dev) 488 { 489 return 490 /* IFLA_IPTUN_LINK */ 491 nla_total_size(4) + 492 /* IFLA_IPTUN_LOCAL */ 493 nla_total_size(4) + 494 /* IFLA_IPTUN_REMOTE */ 495 nla_total_size(4) + 496 /* IFLA_IPTUN_TTL */ 497 nla_total_size(1) + 498 /* IFLA_IPTUN_TOS */ 499 nla_total_size(1) + 500 /* IFLA_IPTUN_PROTO */ 501 nla_total_size(1) + 502 /* IFLA_IPTUN_PMTUDISC */ 503 nla_total_size(1) + 504 /* IFLA_IPTUN_ENCAP_TYPE */ 505 nla_total_size(2) + 506 /* IFLA_IPTUN_ENCAP_FLAGS */ 507 nla_total_size(2) + 508 /* IFLA_IPTUN_ENCAP_SPORT */ 509 nla_total_size(2) + 510 /* IFLA_IPTUN_ENCAP_DPORT */ 511 nla_total_size(2) + 512 /* IFLA_IPTUN_COLLECT_METADATA */ 513 nla_total_size(0) + 514 /* IFLA_IPTUN_FWMARK */ 515 nla_total_size(4) + 516 0; 517 } 518 519 static int ipip_fill_info(struct sk_buff *skb, const struct net_device *dev) 520 { 521 struct ip_tunnel *tunnel = netdev_priv(dev); 522 struct ip_tunnel_parm_kern *parm = &tunnel->parms; 523 524 if (nla_put_u32(skb, IFLA_IPTUN_LINK, parm->link) || 525 nla_put_in_addr(skb, IFLA_IPTUN_LOCAL, parm->iph.saddr) || 526 nla_put_in_addr(skb, IFLA_IPTUN_REMOTE, parm->iph.daddr) || 527 nla_put_u8(skb, IFLA_IPTUN_TTL, parm->iph.ttl) || 528 nla_put_u8(skb, IFLA_IPTUN_TOS, parm->iph.tos) || 529 nla_put_u8(skb, IFLA_IPTUN_PROTO, parm->iph.protocol) || 530 nla_put_u8(skb, IFLA_IPTUN_PMTUDISC, 531 !!(parm->iph.frag_off & htons(IP_DF))) || 532 nla_put_u32(skb, IFLA_IPTUN_FWMARK, tunnel->fwmark)) 533 goto nla_put_failure; 534 535 if (nla_put_u16(skb, IFLA_IPTUN_ENCAP_TYPE, 536 tunnel->encap.type) || 537 nla_put_be16(skb, IFLA_IPTUN_ENCAP_SPORT, 538 tunnel->encap.sport) || 539 nla_put_be16(skb, IFLA_IPTUN_ENCAP_DPORT, 540 tunnel->encap.dport) || 541 nla_put_u16(skb, IFLA_IPTUN_ENCAP_FLAGS, 542 tunnel->encap.flags)) 543 goto nla_put_failure; 544 545 if (tunnel->collect_md) 546 if (nla_put_flag(skb, IFLA_IPTUN_COLLECT_METADATA)) 547 goto nla_put_failure; 548 return 0; 549 550 nla_put_failure: 551 return -EMSGSIZE; 552 } 553 554 static const struct nla_policy ipip_policy[IFLA_IPTUN_MAX + 1] = { 555 [IFLA_IPTUN_LINK] = { .type = NLA_U32 }, 556 [IFLA_IPTUN_LOCAL] = { .type = NLA_U32 }, 557 [IFLA_IPTUN_REMOTE] = { .type = NLA_U32 }, 558 [IFLA_IPTUN_TTL] = { .type = NLA_U8 }, 559 [IFLA_IPTUN_TOS] = { .type = NLA_U8 }, 560 [IFLA_IPTUN_PROTO] = { .type = NLA_U8 }, 561 [IFLA_IPTUN_PMTUDISC] = { .type = NLA_U8 }, 562 [IFLA_IPTUN_ENCAP_TYPE] = { .type = NLA_U16 }, 563 [IFLA_IPTUN_ENCAP_FLAGS] = { .type = NLA_U16 }, 564 [IFLA_IPTUN_ENCAP_SPORT] = { .type = NLA_U16 }, 565 [IFLA_IPTUN_ENCAP_DPORT] = { .type = NLA_U16 }, 566 [IFLA_IPTUN_COLLECT_METADATA] = { .type = NLA_FLAG }, 567 [IFLA_IPTUN_FWMARK] = { .type = NLA_U32 }, 568 }; 569 570 static struct rtnl_link_ops ipip_link_ops __read_mostly = { 571 .kind = "ipip", 572 .maxtype = IFLA_IPTUN_MAX, 573 .policy = ipip_policy, 574 .priv_size = sizeof(struct ip_tunnel), 575 .setup = ipip_tunnel_setup, 576 .validate = ipip_tunnel_validate, 577 .newlink = ipip_newlink, 578 .changelink = ipip_changelink, 579 .dellink = ip_tunnel_dellink, 580 .get_size = ipip_get_size, 581 .fill_info = ipip_fill_info, 582 .get_link_net = ip_tunnel_get_link_net, 583 }; 584 585 static struct xfrm_tunnel ipip_handler __read_mostly = { 586 .handler = ipip_rcv, 587 .err_handler = ipip_err, 588 .priority = 1, 589 }; 590 591 #if IS_ENABLED(CONFIG_MPLS) 592 static struct xfrm_tunnel mplsip_handler __read_mostly = { 593 .handler = mplsip_rcv, 594 .err_handler = ipip_err, 595 .priority = 1, 596 }; 597 #endif 598 599 static int __net_init ipip_init_net(struct net *net) 600 { 601 return ip_tunnel_init_net(net, ipip_net_id, &ipip_link_ops, "tunl0"); 602 } 603 604 static void __net_exit ipip_exit_batch_rtnl(struct list_head *list_net, 605 struct list_head *dev_to_kill) 606 { 607 ip_tunnel_delete_nets(list_net, ipip_net_id, &ipip_link_ops, 608 dev_to_kill); 609 } 610 611 static struct pernet_operations ipip_net_ops = { 612 .init = ipip_init_net, 613 .exit_batch_rtnl = ipip_exit_batch_rtnl, 614 .id = &ipip_net_id, 615 .size = sizeof(struct ip_tunnel_net), 616 }; 617 618 static int __init ipip_init(void) 619 { 620 int err; 621 622 pr_info("ipip: IPv4 and MPLS over IPv4 tunneling driver\n"); 623 624 err = register_pernet_device(&ipip_net_ops); 625 if (err < 0) 626 return err; 627 err = xfrm4_tunnel_register(&ipip_handler, AF_INET); 628 if (err < 0) { 629 pr_info("%s: can't register tunnel\n", __func__); 630 goto xfrm_tunnel_ipip_failed; 631 } 632 #if IS_ENABLED(CONFIG_MPLS) 633 err = xfrm4_tunnel_register(&mplsip_handler, AF_MPLS); 634 if (err < 0) { 635 pr_info("%s: can't register tunnel\n", __func__); 636 goto xfrm_tunnel_mplsip_failed; 637 } 638 #endif 639 err = rtnl_link_register(&ipip_link_ops); 640 if (err < 0) 641 goto rtnl_link_failed; 642 643 out: 644 return err; 645 646 rtnl_link_failed: 647 #if IS_ENABLED(CONFIG_MPLS) 648 xfrm4_tunnel_deregister(&mplsip_handler, AF_MPLS); 649 xfrm_tunnel_mplsip_failed: 650 651 #endif 652 xfrm4_tunnel_deregister(&ipip_handler, AF_INET); 653 xfrm_tunnel_ipip_failed: 654 unregister_pernet_device(&ipip_net_ops); 655 goto out; 656 } 657 658 static void __exit ipip_fini(void) 659 { 660 rtnl_link_unregister(&ipip_link_ops); 661 if (xfrm4_tunnel_deregister(&ipip_handler, AF_INET)) 662 pr_info("%s: can't deregister tunnel\n", __func__); 663 #if IS_ENABLED(CONFIG_MPLS) 664 if (xfrm4_tunnel_deregister(&mplsip_handler, AF_MPLS)) 665 pr_info("%s: can't deregister tunnel\n", __func__); 666 #endif 667 unregister_pernet_device(&ipip_net_ops); 668 } 669 670 module_init(ipip_init); 671 module_exit(ipip_fini); 672 MODULE_DESCRIPTION("IP/IP protocol decoder library"); 673 MODULE_LICENSE("GPL"); 674 MODULE_ALIAS_RTNL_LINK("ipip"); 675 MODULE_ALIAS_NETDEV("tunl0"); 676