1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * IPv6 over IPv4 tunnel device - Simple Internet Transition (SIT) 4 * Linux INET6 implementation 5 * 6 * Authors: 7 * Pedro Roque <roque@di.fc.ul.pt> 8 * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> 9 * 10 * Changes: 11 * Roger Venning <r.venning@telstra.com>: 6to4 support 12 * Nate Thompson <nate@thebog.net>: 6to4 support 13 * Fred Templin <fred.l.templin@boeing.com>: isatap support 14 */ 15 16 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 17 18 #include <linux/module.h> 19 #include <linux/capability.h> 20 #include <linux/errno.h> 21 #include <linux/types.h> 22 #include <linux/socket.h> 23 #include <linux/sockios.h> 24 #include <linux/net.h> 25 #include <linux/in6.h> 26 #include <linux/netdevice.h> 27 #include <linux/if_arp.h> 28 #include <linux/icmp.h> 29 #include <linux/slab.h> 30 #include <linux/uaccess.h> 31 #include <linux/init.h> 32 #include <linux/netfilter_ipv4.h> 33 #include <linux/if_ether.h> 34 35 #include <net/sock.h> 36 #include <net/snmp.h> 37 38 #include <net/ipv6.h> 39 #include <net/protocol.h> 40 #include <net/transp_v6.h> 41 #include <net/ip6_fib.h> 42 #include <net/ip6_route.h> 43 #include <net/ndisc.h> 44 #include <net/addrconf.h> 45 #include <net/ip.h> 46 #include <net/udp.h> 47 #include <net/icmp.h> 48 #include <net/ip_tunnels.h> 49 #include <net/inet_ecn.h> 50 #include <net/xfrm.h> 51 #include <net/dsfield.h> 52 #include <net/net_namespace.h> 53 #include <net/netns/generic.h> 54 55 /* 56 This version of net/ipv6/sit.c is cloned of net/ipv4/ip_gre.c 57 58 For comments look at net/ipv4/ip_gre.c --ANK 59 */ 60 61 #define IP6_SIT_HASH_SIZE 16 62 #define HASH(addr) (((__force u32)addr^((__force u32)addr>>4))&0xF) 63 64 static bool log_ecn_error = true; 65 module_param(log_ecn_error, bool, 0644); 66 MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN"); 67 68 static int ipip6_tunnel_init(struct net_device *dev); 69 static void ipip6_tunnel_setup(struct net_device *dev); 70 static void ipip6_dev_free(struct net_device *dev); 71 static bool check_6rd(struct ip_tunnel *tunnel, const struct in6_addr *v6dst, 72 __be32 *v4dst); 73 static struct rtnl_link_ops sit_link_ops __read_mostly; 74 75 static unsigned int sit_net_id __read_mostly; 76 struct sit_net { 77 struct ip_tunnel __rcu *tunnels_r_l[IP6_SIT_HASH_SIZE]; 78 struct ip_tunnel __rcu *tunnels_r[IP6_SIT_HASH_SIZE]; 79 struct ip_tunnel __rcu *tunnels_l[IP6_SIT_HASH_SIZE]; 80 struct ip_tunnel __rcu *tunnels_wc[1]; 81 struct ip_tunnel __rcu **tunnels[4]; 82 83 struct net_device *fb_tunnel_dev; 84 }; 85 86 static inline struct sit_net *dev_to_sit_net(struct net_device *dev) 87 { 88 struct ip_tunnel *t = netdev_priv(dev); 89 90 return net_generic(t->net, sit_net_id); 91 } 92 93 /* 94 * Must be invoked with rcu_read_lock 95 */ 96 static struct ip_tunnel *ipip6_tunnel_lookup(struct net *net, 97 struct net_device *dev, 98 __be32 remote, __be32 local, 99 int sifindex) 100 { 101 unsigned int h0 = HASH(remote); 102 unsigned int h1 = HASH(local); 103 struct ip_tunnel *t; 104 struct sit_net *sitn = net_generic(net, sit_net_id); 105 int ifindex = dev ? dev->ifindex : 0; 106 107 for_each_ip_tunnel_rcu(t, sitn->tunnels_r_l[h0 ^ h1]) { 108 if (local == t->parms.iph.saddr && 109 remote == t->parms.iph.daddr && 110 (!dev || !t->parms.link || ifindex == t->parms.link || 111 sifindex == t->parms.link) && 112 (t->dev->flags & IFF_UP)) 113 return t; 114 } 115 for_each_ip_tunnel_rcu(t, sitn->tunnels_r[h0]) { 116 if (remote == t->parms.iph.daddr && 117 (!dev || !t->parms.link || ifindex == t->parms.link || 118 sifindex == t->parms.link) && 119 (t->dev->flags & IFF_UP)) 120 return t; 121 } 122 for_each_ip_tunnel_rcu(t, sitn->tunnels_l[h1]) { 123 if (local == t->parms.iph.saddr && 124 (!dev || !t->parms.link || ifindex == t->parms.link || 125 sifindex == t->parms.link) && 126 (t->dev->flags & IFF_UP)) 127 return t; 128 } 129 t = rcu_dereference(sitn->tunnels_wc[0]); 130 if (t && (t->dev->flags & IFF_UP)) 131 return t; 132 return NULL; 133 } 134 135 static struct ip_tunnel __rcu **__ipip6_bucket(struct sit_net *sitn, 136 struct ip_tunnel_parm *parms) 137 { 138 __be32 remote = parms->iph.daddr; 139 __be32 local = parms->iph.saddr; 140 unsigned int h = 0; 141 int prio = 0; 142 143 if (remote) { 144 prio |= 2; 145 h ^= HASH(remote); 146 } 147 if (local) { 148 prio |= 1; 149 h ^= HASH(local); 150 } 151 return &sitn->tunnels[prio][h]; 152 } 153 154 static inline struct ip_tunnel __rcu **ipip6_bucket(struct sit_net *sitn, 155 struct ip_tunnel *t) 156 { 157 return __ipip6_bucket(sitn, &t->parms); 158 } 159 160 static void ipip6_tunnel_unlink(struct sit_net *sitn, struct ip_tunnel *t) 161 { 162 struct ip_tunnel __rcu **tp; 163 struct ip_tunnel *iter; 164 165 for (tp = ipip6_bucket(sitn, t); 166 (iter = rtnl_dereference(*tp)) != NULL; 167 tp = &iter->next) { 168 if (t == iter) { 169 rcu_assign_pointer(*tp, t->next); 170 break; 171 } 172 } 173 } 174 175 static void ipip6_tunnel_link(struct sit_net *sitn, struct ip_tunnel *t) 176 { 177 struct ip_tunnel __rcu **tp = ipip6_bucket(sitn, t); 178 179 rcu_assign_pointer(t->next, rtnl_dereference(*tp)); 180 rcu_assign_pointer(*tp, t); 181 } 182 183 static void ipip6_tunnel_clone_6rd(struct net_device *dev, struct sit_net *sitn) 184 { 185 #ifdef CONFIG_IPV6_SIT_6RD 186 struct ip_tunnel *t = netdev_priv(dev); 187 188 if (dev == sitn->fb_tunnel_dev || !sitn->fb_tunnel_dev) { 189 ipv6_addr_set(&t->ip6rd.prefix, htonl(0x20020000), 0, 0, 0); 190 t->ip6rd.relay_prefix = 0; 191 t->ip6rd.prefixlen = 16; 192 t->ip6rd.relay_prefixlen = 0; 193 } else { 194 struct ip_tunnel *t0 = netdev_priv(sitn->fb_tunnel_dev); 195 memcpy(&t->ip6rd, &t0->ip6rd, sizeof(t->ip6rd)); 196 } 197 #endif 198 } 199 200 static int ipip6_tunnel_create(struct net_device *dev) 201 { 202 struct ip_tunnel *t = netdev_priv(dev); 203 struct net *net = dev_net(dev); 204 struct sit_net *sitn = net_generic(net, sit_net_id); 205 int err; 206 207 __dev_addr_set(dev, &t->parms.iph.saddr, 4); 208 memcpy(dev->broadcast, &t->parms.iph.daddr, 4); 209 210 if ((__force u16)t->parms.i_flags & SIT_ISATAP) 211 dev->priv_flags |= IFF_ISATAP; 212 213 dev->rtnl_link_ops = &sit_link_ops; 214 215 err = register_netdevice(dev); 216 if (err < 0) 217 goto out; 218 219 ipip6_tunnel_clone_6rd(dev, sitn); 220 221 ipip6_tunnel_link(sitn, t); 222 return 0; 223 224 out: 225 return err; 226 } 227 228 static struct ip_tunnel *ipip6_tunnel_locate(struct net *net, 229 struct ip_tunnel_parm *parms, int create) 230 { 231 __be32 remote = parms->iph.daddr; 232 __be32 local = parms->iph.saddr; 233 struct ip_tunnel *t, *nt; 234 struct ip_tunnel __rcu **tp; 235 struct net_device *dev; 236 char name[IFNAMSIZ]; 237 struct sit_net *sitn = net_generic(net, sit_net_id); 238 239 for (tp = __ipip6_bucket(sitn, parms); 240 (t = rtnl_dereference(*tp)) != NULL; 241 tp = &t->next) { 242 if (local == t->parms.iph.saddr && 243 remote == t->parms.iph.daddr && 244 parms->link == t->parms.link) { 245 if (create) 246 return NULL; 247 else 248 return t; 249 } 250 } 251 if (!create) 252 goto failed; 253 254 if (parms->name[0]) { 255 if (!dev_valid_name(parms->name)) 256 goto failed; 257 strscpy(name, parms->name, IFNAMSIZ); 258 } else { 259 strcpy(name, "sit%d"); 260 } 261 dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN, 262 ipip6_tunnel_setup); 263 if (!dev) 264 return NULL; 265 266 dev_net_set(dev, net); 267 268 nt = netdev_priv(dev); 269 270 nt->parms = *parms; 271 if (ipip6_tunnel_create(dev) < 0) 272 goto failed_free; 273 274 if (!parms->name[0]) 275 strcpy(parms->name, dev->name); 276 277 return nt; 278 279 failed_free: 280 free_netdev(dev); 281 failed: 282 return NULL; 283 } 284 285 #define for_each_prl_rcu(start) \ 286 for (prl = rcu_dereference(start); \ 287 prl; \ 288 prl = rcu_dereference(prl->next)) 289 290 static struct ip_tunnel_prl_entry * 291 __ipip6_tunnel_locate_prl(struct ip_tunnel *t, __be32 addr) 292 { 293 struct ip_tunnel_prl_entry *prl; 294 295 for_each_prl_rcu(t->prl) 296 if (prl->addr == addr) 297 break; 298 return prl; 299 300 } 301 302 static int ipip6_tunnel_get_prl(struct net_device *dev, struct ip_tunnel_prl __user *a) 303 { 304 struct ip_tunnel *t = netdev_priv(dev); 305 struct ip_tunnel_prl kprl, *kp; 306 struct ip_tunnel_prl_entry *prl; 307 unsigned int cmax, c = 0, ca, len; 308 int ret = 0; 309 310 if (dev == dev_to_sit_net(dev)->fb_tunnel_dev) 311 return -EINVAL; 312 313 if (copy_from_user(&kprl, a, sizeof(kprl))) 314 return -EFAULT; 315 cmax = kprl.datalen / sizeof(kprl); 316 if (cmax > 1 && kprl.addr != htonl(INADDR_ANY)) 317 cmax = 1; 318 319 /* For simple GET or for root users, 320 * we try harder to allocate. 321 */ 322 kp = (cmax <= 1 || capable(CAP_NET_ADMIN)) ? 323 kcalloc(cmax, sizeof(*kp), GFP_KERNEL_ACCOUNT | __GFP_NOWARN) : 324 NULL; 325 326 ca = min(t->prl_count, cmax); 327 328 if (!kp) { 329 /* We don't try hard to allocate much memory for 330 * non-root users. 331 * For root users, retry allocating enough memory for 332 * the answer. 333 */ 334 kp = kcalloc(ca, sizeof(*kp), GFP_ATOMIC | __GFP_ACCOUNT | 335 __GFP_NOWARN); 336 if (!kp) { 337 ret = -ENOMEM; 338 goto out; 339 } 340 } 341 342 rcu_read_lock(); 343 for_each_prl_rcu(t->prl) { 344 if (c >= cmax) 345 break; 346 if (kprl.addr != htonl(INADDR_ANY) && prl->addr != kprl.addr) 347 continue; 348 kp[c].addr = prl->addr; 349 kp[c].flags = prl->flags; 350 c++; 351 if (kprl.addr != htonl(INADDR_ANY)) 352 break; 353 } 354 355 rcu_read_unlock(); 356 357 len = sizeof(*kp) * c; 358 ret = 0; 359 if ((len && copy_to_user(a + 1, kp, len)) || put_user(len, &a->datalen)) 360 ret = -EFAULT; 361 362 kfree(kp); 363 out: 364 return ret; 365 } 366 367 static int 368 ipip6_tunnel_add_prl(struct ip_tunnel *t, struct ip_tunnel_prl *a, int chg) 369 { 370 struct ip_tunnel_prl_entry *p; 371 int err = 0; 372 373 if (a->addr == htonl(INADDR_ANY)) 374 return -EINVAL; 375 376 ASSERT_RTNL(); 377 378 for (p = rtnl_dereference(t->prl); p; p = rtnl_dereference(p->next)) { 379 if (p->addr == a->addr) { 380 if (chg) { 381 p->flags = a->flags; 382 goto out; 383 } 384 err = -EEXIST; 385 goto out; 386 } 387 } 388 389 if (chg) { 390 err = -ENXIO; 391 goto out; 392 } 393 394 p = kzalloc(sizeof(struct ip_tunnel_prl_entry), GFP_KERNEL); 395 if (!p) { 396 err = -ENOBUFS; 397 goto out; 398 } 399 400 p->next = t->prl; 401 p->addr = a->addr; 402 p->flags = a->flags; 403 t->prl_count++; 404 rcu_assign_pointer(t->prl, p); 405 out: 406 return err; 407 } 408 409 static void prl_list_destroy_rcu(struct rcu_head *head) 410 { 411 struct ip_tunnel_prl_entry *p, *n; 412 413 p = container_of(head, struct ip_tunnel_prl_entry, rcu_head); 414 do { 415 n = rcu_dereference_protected(p->next, 1); 416 kfree(p); 417 p = n; 418 } while (p); 419 } 420 421 static int 422 ipip6_tunnel_del_prl(struct ip_tunnel *t, struct ip_tunnel_prl *a) 423 { 424 struct ip_tunnel_prl_entry *x; 425 struct ip_tunnel_prl_entry __rcu **p; 426 int err = 0; 427 428 ASSERT_RTNL(); 429 430 if (a && a->addr != htonl(INADDR_ANY)) { 431 for (p = &t->prl; 432 (x = rtnl_dereference(*p)) != NULL; 433 p = &x->next) { 434 if (x->addr == a->addr) { 435 *p = x->next; 436 kfree_rcu(x, rcu_head); 437 t->prl_count--; 438 goto out; 439 } 440 } 441 err = -ENXIO; 442 } else { 443 x = rtnl_dereference(t->prl); 444 if (x) { 445 t->prl_count = 0; 446 call_rcu(&x->rcu_head, prl_list_destroy_rcu); 447 t->prl = NULL; 448 } 449 } 450 out: 451 return err; 452 } 453 454 static int ipip6_tunnel_prl_ctl(struct net_device *dev, 455 struct ip_tunnel_prl __user *data, int cmd) 456 { 457 struct ip_tunnel *t = netdev_priv(dev); 458 struct ip_tunnel_prl prl; 459 int err; 460 461 if (!ns_capable(t->net->user_ns, CAP_NET_ADMIN)) 462 return -EPERM; 463 if (dev == dev_to_sit_net(dev)->fb_tunnel_dev) 464 return -EINVAL; 465 466 if (copy_from_user(&prl, data, sizeof(prl))) 467 return -EFAULT; 468 469 switch (cmd) { 470 case SIOCDELPRL: 471 err = ipip6_tunnel_del_prl(t, &prl); 472 break; 473 case SIOCADDPRL: 474 case SIOCCHGPRL: 475 err = ipip6_tunnel_add_prl(t, &prl, cmd == SIOCCHGPRL); 476 break; 477 } 478 dst_cache_reset(&t->dst_cache); 479 netdev_state_change(dev); 480 return err; 481 } 482 483 static int 484 isatap_chksrc(struct sk_buff *skb, const struct iphdr *iph, struct ip_tunnel *t) 485 { 486 struct ip_tunnel_prl_entry *p; 487 int ok = 1; 488 489 rcu_read_lock(); 490 p = __ipip6_tunnel_locate_prl(t, iph->saddr); 491 if (p) { 492 if (p->flags & PRL_DEFAULT) 493 skb->ndisc_nodetype = NDISC_NODETYPE_DEFAULT; 494 else 495 skb->ndisc_nodetype = NDISC_NODETYPE_NODEFAULT; 496 } else { 497 const struct in6_addr *addr6 = &ipv6_hdr(skb)->saddr; 498 499 if (ipv6_addr_is_isatap(addr6) && 500 (addr6->s6_addr32[3] == iph->saddr) && 501 ipv6_chk_prefix(addr6, t->dev)) 502 skb->ndisc_nodetype = NDISC_NODETYPE_HOST; 503 else 504 ok = 0; 505 } 506 rcu_read_unlock(); 507 return ok; 508 } 509 510 static void ipip6_tunnel_uninit(struct net_device *dev) 511 { 512 struct ip_tunnel *tunnel = netdev_priv(dev); 513 struct sit_net *sitn = net_generic(tunnel->net, sit_net_id); 514 515 if (dev == sitn->fb_tunnel_dev) { 516 RCU_INIT_POINTER(sitn->tunnels_wc[0], NULL); 517 } else { 518 ipip6_tunnel_unlink(sitn, tunnel); 519 ipip6_tunnel_del_prl(tunnel, NULL); 520 } 521 dst_cache_reset(&tunnel->dst_cache); 522 netdev_put(dev, &tunnel->dev_tracker); 523 } 524 525 static int ipip6_err(struct sk_buff *skb, u32 info) 526 { 527 const struct iphdr *iph = (const struct iphdr *)skb->data; 528 const int type = icmp_hdr(skb)->type; 529 const int code = icmp_hdr(skb)->code; 530 unsigned int data_len = 0; 531 struct ip_tunnel *t; 532 int sifindex; 533 int err; 534 535 switch (type) { 536 default: 537 case ICMP_PARAMETERPROB: 538 return 0; 539 540 case ICMP_DEST_UNREACH: 541 switch (code) { 542 case ICMP_SR_FAILED: 543 /* Impossible event. */ 544 return 0; 545 default: 546 /* All others are translated to HOST_UNREACH. 547 rfc2003 contains "deep thoughts" about NET_UNREACH, 548 I believe they are just ether pollution. --ANK 549 */ 550 break; 551 } 552 break; 553 case ICMP_TIME_EXCEEDED: 554 if (code != ICMP_EXC_TTL) 555 return 0; 556 data_len = icmp_hdr(skb)->un.reserved[1] * 4; /* RFC 4884 4.1 */ 557 break; 558 case ICMP_REDIRECT: 559 break; 560 } 561 562 err = -ENOENT; 563 564 sifindex = netif_is_l3_master(skb->dev) ? IPCB(skb)->iif : 0; 565 t = ipip6_tunnel_lookup(dev_net(skb->dev), skb->dev, 566 iph->daddr, iph->saddr, sifindex); 567 if (!t) 568 goto out; 569 570 if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) { 571 ipv4_update_pmtu(skb, dev_net(skb->dev), info, 572 t->parms.link, iph->protocol); 573 err = 0; 574 goto out; 575 } 576 if (type == ICMP_REDIRECT) { 577 ipv4_redirect(skb, dev_net(skb->dev), t->parms.link, 578 iph->protocol); 579 err = 0; 580 goto out; 581 } 582 583 err = 0; 584 if (__in6_dev_get(skb->dev) && 585 !ip6_err_gen_icmpv6_unreach(skb, iph->ihl * 4, type, data_len)) 586 goto out; 587 588 if (t->parms.iph.daddr == 0) 589 goto out; 590 591 if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED) 592 goto out; 593 594 if (time_before(jiffies, t->err_time + IPTUNNEL_ERR_TIMEO)) 595 t->err_count++; 596 else 597 t->err_count = 1; 598 t->err_time = jiffies; 599 out: 600 return err; 601 } 602 603 static inline bool is_spoofed_6rd(struct ip_tunnel *tunnel, const __be32 v4addr, 604 const struct in6_addr *v6addr) 605 { 606 __be32 v4embed = 0; 607 if (check_6rd(tunnel, v6addr, &v4embed) && v4addr != v4embed) 608 return true; 609 return false; 610 } 611 612 /* Checks if an address matches an address on the tunnel interface. 613 * Used to detect the NAT of proto 41 packets and let them pass spoofing test. 614 * Long story: 615 * This function is called after we considered the packet as spoofed 616 * in is_spoofed_6rd. 617 * We may have a router that is doing NAT for proto 41 packets 618 * for an internal station. Destination a.a.a.a/PREFIX:bbbb:bbbb 619 * will be translated to n.n.n.n/PREFIX:bbbb:bbbb. And is_spoofed_6rd 620 * function will return true, dropping the packet. 621 * But, we can still check if is spoofed against the IP 622 * addresses associated with the interface. 623 */ 624 static bool only_dnatted(const struct ip_tunnel *tunnel, 625 const struct in6_addr *v6dst) 626 { 627 int prefix_len; 628 629 #ifdef CONFIG_IPV6_SIT_6RD 630 prefix_len = tunnel->ip6rd.prefixlen + 32 631 - tunnel->ip6rd.relay_prefixlen; 632 #else 633 prefix_len = 48; 634 #endif 635 return ipv6_chk_custom_prefix(v6dst, prefix_len, tunnel->dev); 636 } 637 638 /* Returns true if a packet is spoofed */ 639 static bool packet_is_spoofed(struct sk_buff *skb, 640 const struct iphdr *iph, 641 struct ip_tunnel *tunnel) 642 { 643 const struct ipv6hdr *ipv6h; 644 645 if (tunnel->dev->priv_flags & IFF_ISATAP) { 646 if (!isatap_chksrc(skb, iph, tunnel)) 647 return true; 648 649 return false; 650 } 651 652 if (tunnel->dev->flags & IFF_POINTOPOINT) 653 return false; 654 655 ipv6h = ipv6_hdr(skb); 656 657 if (unlikely(is_spoofed_6rd(tunnel, iph->saddr, &ipv6h->saddr))) { 658 net_warn_ratelimited("Src spoofed %pI4/%pI6c -> %pI4/%pI6c\n", 659 &iph->saddr, &ipv6h->saddr, 660 &iph->daddr, &ipv6h->daddr); 661 return true; 662 } 663 664 if (likely(!is_spoofed_6rd(tunnel, iph->daddr, &ipv6h->daddr))) 665 return false; 666 667 if (only_dnatted(tunnel, &ipv6h->daddr)) 668 return false; 669 670 net_warn_ratelimited("Dst spoofed %pI4/%pI6c -> %pI4/%pI6c\n", 671 &iph->saddr, &ipv6h->saddr, 672 &iph->daddr, &ipv6h->daddr); 673 return true; 674 } 675 676 static int ipip6_rcv(struct sk_buff *skb) 677 { 678 const struct iphdr *iph = ip_hdr(skb); 679 struct ip_tunnel *tunnel; 680 int sifindex; 681 int err; 682 683 sifindex = netif_is_l3_master(skb->dev) ? IPCB(skb)->iif : 0; 684 tunnel = ipip6_tunnel_lookup(dev_net(skb->dev), skb->dev, 685 iph->saddr, iph->daddr, sifindex); 686 if (tunnel) { 687 if (tunnel->parms.iph.protocol != IPPROTO_IPV6 && 688 tunnel->parms.iph.protocol != 0) 689 goto out; 690 691 skb->mac_header = skb->network_header; 692 skb_reset_network_header(skb); 693 IPCB(skb)->flags = 0; 694 skb->dev = tunnel->dev; 695 696 if (packet_is_spoofed(skb, iph, tunnel)) { 697 DEV_STATS_INC(tunnel->dev, rx_errors); 698 goto out; 699 } 700 701 if (iptunnel_pull_header(skb, 0, htons(ETH_P_IPV6), 702 !net_eq(tunnel->net, dev_net(tunnel->dev)))) 703 goto out; 704 705 /* skb can be uncloned in iptunnel_pull_header, so 706 * old iph is no longer valid 707 */ 708 iph = (const struct iphdr *)skb_mac_header(skb); 709 skb_reset_mac_header(skb); 710 711 err = IP_ECN_decapsulate(iph, skb); 712 if (unlikely(err)) { 713 if (log_ecn_error) 714 net_info_ratelimited("non-ECT from %pI4 with TOS=%#x\n", 715 &iph->saddr, iph->tos); 716 if (err > 1) { 717 DEV_STATS_INC(tunnel->dev, rx_frame_errors); 718 DEV_STATS_INC(tunnel->dev, rx_errors); 719 goto out; 720 } 721 } 722 723 dev_sw_netstats_rx_add(tunnel->dev, skb->len); 724 725 netif_rx(skb); 726 727 return 0; 728 } 729 730 /* no tunnel matched, let upstream know, ipsec may handle it */ 731 return 1; 732 out: 733 kfree_skb(skb); 734 return 0; 735 } 736 737 static const struct tnl_ptk_info ipip_tpi = { 738 /* no tunnel info required for ipip. */ 739 .proto = htons(ETH_P_IP), 740 }; 741 742 #if IS_ENABLED(CONFIG_MPLS) 743 static const struct tnl_ptk_info mplsip_tpi = { 744 /* no tunnel info required for mplsip. */ 745 .proto = htons(ETH_P_MPLS_UC), 746 }; 747 #endif 748 749 static int sit_tunnel_rcv(struct sk_buff *skb, u8 ipproto) 750 { 751 const struct iphdr *iph; 752 struct ip_tunnel *tunnel; 753 int sifindex; 754 755 sifindex = netif_is_l3_master(skb->dev) ? IPCB(skb)->iif : 0; 756 757 iph = ip_hdr(skb); 758 tunnel = ipip6_tunnel_lookup(dev_net(skb->dev), skb->dev, 759 iph->saddr, iph->daddr, sifindex); 760 if (tunnel) { 761 const struct tnl_ptk_info *tpi; 762 763 if (tunnel->parms.iph.protocol != ipproto && 764 tunnel->parms.iph.protocol != 0) 765 goto drop; 766 767 if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) 768 goto drop; 769 #if IS_ENABLED(CONFIG_MPLS) 770 if (ipproto == IPPROTO_MPLS) 771 tpi = &mplsip_tpi; 772 else 773 #endif 774 tpi = &ipip_tpi; 775 if (iptunnel_pull_header(skb, 0, tpi->proto, false)) 776 goto drop; 777 skb_reset_mac_header(skb); 778 779 return ip_tunnel_rcv(tunnel, skb, tpi, NULL, log_ecn_error); 780 } 781 782 return 1; 783 784 drop: 785 kfree_skb(skb); 786 return 0; 787 } 788 789 static int ipip_rcv(struct sk_buff *skb) 790 { 791 return sit_tunnel_rcv(skb, IPPROTO_IPIP); 792 } 793 794 #if IS_ENABLED(CONFIG_MPLS) 795 static int mplsip_rcv(struct sk_buff *skb) 796 { 797 return sit_tunnel_rcv(skb, IPPROTO_MPLS); 798 } 799 #endif 800 801 /* 802 * If the IPv6 address comes from 6rd / 6to4 (RFC 3056) addr space this function 803 * stores the embedded IPv4 address in v4dst and returns true. 804 */ 805 static bool check_6rd(struct ip_tunnel *tunnel, const struct in6_addr *v6dst, 806 __be32 *v4dst) 807 { 808 #ifdef CONFIG_IPV6_SIT_6RD 809 if (ipv6_prefix_equal(v6dst, &tunnel->ip6rd.prefix, 810 tunnel->ip6rd.prefixlen)) { 811 unsigned int pbw0, pbi0; 812 int pbi1; 813 u32 d; 814 815 pbw0 = tunnel->ip6rd.prefixlen >> 5; 816 pbi0 = tunnel->ip6rd.prefixlen & 0x1f; 817 818 d = tunnel->ip6rd.relay_prefixlen < 32 ? 819 (ntohl(v6dst->s6_addr32[pbw0]) << pbi0) >> 820 tunnel->ip6rd.relay_prefixlen : 0; 821 822 pbi1 = pbi0 - tunnel->ip6rd.relay_prefixlen; 823 if (pbi1 > 0) 824 d |= ntohl(v6dst->s6_addr32[pbw0 + 1]) >> 825 (32 - pbi1); 826 827 *v4dst = tunnel->ip6rd.relay_prefix | htonl(d); 828 return true; 829 } 830 #else 831 if (v6dst->s6_addr16[0] == htons(0x2002)) { 832 /* 6to4 v6 addr has 16 bits prefix, 32 v4addr, 16 SLA, ... */ 833 memcpy(v4dst, &v6dst->s6_addr16[1], 4); 834 return true; 835 } 836 #endif 837 return false; 838 } 839 840 static inline __be32 try_6rd(struct ip_tunnel *tunnel, 841 const struct in6_addr *v6dst) 842 { 843 __be32 dst = 0; 844 check_6rd(tunnel, v6dst, &dst); 845 return dst; 846 } 847 848 /* 849 * This function assumes it is being called from dev_queue_xmit() 850 * and that skb is filled properly by that function. 851 */ 852 853 static netdev_tx_t ipip6_tunnel_xmit(struct sk_buff *skb, 854 struct net_device *dev) 855 { 856 struct ip_tunnel *tunnel = netdev_priv(dev); 857 const struct iphdr *tiph = &tunnel->parms.iph; 858 const struct ipv6hdr *iph6 = ipv6_hdr(skb); 859 u8 tos = tunnel->parms.iph.tos; 860 __be16 df = tiph->frag_off; 861 struct rtable *rt; /* Route to the other host */ 862 struct net_device *tdev; /* Device to other host */ 863 unsigned int max_headroom; /* The extra header space needed */ 864 __be32 dst = tiph->daddr; 865 struct flowi4 fl4; 866 int mtu; 867 const struct in6_addr *addr6; 868 int addr_type; 869 u8 ttl; 870 u8 protocol = IPPROTO_IPV6; 871 int t_hlen = tunnel->hlen + sizeof(struct iphdr); 872 873 if (tos == 1) 874 tos = ipv6_get_dsfield(iph6); 875 876 /* ISATAP (RFC4214) - must come before 6to4 */ 877 if (dev->priv_flags & IFF_ISATAP) { 878 struct neighbour *neigh = NULL; 879 bool do_tx_error = false; 880 881 if (skb_dst(skb)) 882 neigh = dst_neigh_lookup(skb_dst(skb), &iph6->daddr); 883 884 if (!neigh) { 885 net_dbg_ratelimited("nexthop == NULL\n"); 886 goto tx_error; 887 } 888 889 addr6 = (const struct in6_addr *)&neigh->primary_key; 890 addr_type = ipv6_addr_type(addr6); 891 892 if ((addr_type & IPV6_ADDR_UNICAST) && 893 ipv6_addr_is_isatap(addr6)) 894 dst = addr6->s6_addr32[3]; 895 else 896 do_tx_error = true; 897 898 neigh_release(neigh); 899 if (do_tx_error) 900 goto tx_error; 901 } 902 903 if (!dst) 904 dst = try_6rd(tunnel, &iph6->daddr); 905 906 if (!dst) { 907 struct neighbour *neigh = NULL; 908 bool do_tx_error = false; 909 910 if (skb_dst(skb)) 911 neigh = dst_neigh_lookup(skb_dst(skb), &iph6->daddr); 912 913 if (!neigh) { 914 net_dbg_ratelimited("nexthop == NULL\n"); 915 goto tx_error; 916 } 917 918 addr6 = (const struct in6_addr *)&neigh->primary_key; 919 addr_type = ipv6_addr_type(addr6); 920 921 if (addr_type == IPV6_ADDR_ANY) { 922 addr6 = &ipv6_hdr(skb)->daddr; 923 addr_type = ipv6_addr_type(addr6); 924 } 925 926 if ((addr_type & IPV6_ADDR_COMPATv4) != 0) 927 dst = addr6->s6_addr32[3]; 928 else 929 do_tx_error = true; 930 931 neigh_release(neigh); 932 if (do_tx_error) 933 goto tx_error; 934 } 935 936 flowi4_init_output(&fl4, tunnel->parms.link, tunnel->fwmark, 937 RT_TOS(tos), RT_SCOPE_UNIVERSE, IPPROTO_IPV6, 938 0, dst, tiph->saddr, 0, 0, 939 sock_net_uid(tunnel->net, NULL)); 940 941 rt = dst_cache_get_ip4(&tunnel->dst_cache, &fl4.saddr); 942 if (!rt) { 943 rt = ip_route_output_flow(tunnel->net, &fl4, NULL); 944 if (IS_ERR(rt)) { 945 DEV_STATS_INC(dev, tx_carrier_errors); 946 goto tx_error_icmp; 947 } 948 dst_cache_set_ip4(&tunnel->dst_cache, &rt->dst, fl4.saddr); 949 } 950 951 if (rt->rt_type != RTN_UNICAST && rt->rt_type != RTN_LOCAL) { 952 ip_rt_put(rt); 953 DEV_STATS_INC(dev, tx_carrier_errors); 954 goto tx_error_icmp; 955 } 956 tdev = rt->dst.dev; 957 958 if (tdev == dev) { 959 ip_rt_put(rt); 960 DEV_STATS_INC(dev, collisions); 961 goto tx_error; 962 } 963 964 if (iptunnel_handle_offloads(skb, SKB_GSO_IPXIP4)) { 965 ip_rt_put(rt); 966 goto tx_error; 967 } 968 969 if (df) { 970 mtu = dst_mtu(&rt->dst) - t_hlen; 971 972 if (mtu < IPV4_MIN_MTU) { 973 DEV_STATS_INC(dev, collisions); 974 ip_rt_put(rt); 975 goto tx_error; 976 } 977 978 if (mtu < IPV6_MIN_MTU) { 979 mtu = IPV6_MIN_MTU; 980 df = 0; 981 } 982 983 if (tunnel->parms.iph.daddr) 984 skb_dst_update_pmtu_no_confirm(skb, mtu); 985 986 if (skb->len > mtu && !skb_is_gso(skb)) { 987 icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); 988 ip_rt_put(rt); 989 goto tx_error; 990 } 991 } 992 993 if (tunnel->err_count > 0) { 994 if (time_before(jiffies, 995 tunnel->err_time + IPTUNNEL_ERR_TIMEO)) { 996 tunnel->err_count--; 997 dst_link_failure(skb); 998 } else 999 tunnel->err_count = 0; 1000 } 1001 1002 /* 1003 * Okay, now see if we can stuff it in the buffer as-is. 1004 */ 1005 max_headroom = LL_RESERVED_SPACE(tdev) + t_hlen; 1006 1007 if (skb_headroom(skb) < max_headroom || skb_shared(skb) || 1008 (skb_cloned(skb) && !skb_clone_writable(skb, 0))) { 1009 struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom); 1010 if (!new_skb) { 1011 ip_rt_put(rt); 1012 DEV_STATS_INC(dev, tx_dropped); 1013 kfree_skb(skb); 1014 return NETDEV_TX_OK; 1015 } 1016 if (skb->sk) 1017 skb_set_owner_w(new_skb, skb->sk); 1018 dev_kfree_skb(skb); 1019 skb = new_skb; 1020 iph6 = ipv6_hdr(skb); 1021 } 1022 ttl = tiph->ttl; 1023 if (ttl == 0) 1024 ttl = iph6->hop_limit; 1025 tos = INET_ECN_encapsulate(tos, ipv6_get_dsfield(iph6)); 1026 1027 if (ip_tunnel_encap(skb, tunnel, &protocol, &fl4) < 0) { 1028 ip_rt_put(rt); 1029 goto tx_error; 1030 } 1031 1032 skb_set_inner_ipproto(skb, IPPROTO_IPV6); 1033 1034 iptunnel_xmit(NULL, rt, skb, fl4.saddr, fl4.daddr, protocol, tos, ttl, 1035 df, !net_eq(tunnel->net, dev_net(dev))); 1036 return NETDEV_TX_OK; 1037 1038 tx_error_icmp: 1039 dst_link_failure(skb); 1040 tx_error: 1041 kfree_skb(skb); 1042 DEV_STATS_INC(dev, tx_errors); 1043 return NETDEV_TX_OK; 1044 } 1045 1046 static netdev_tx_t sit_tunnel_xmit__(struct sk_buff *skb, 1047 struct net_device *dev, u8 ipproto) 1048 { 1049 struct ip_tunnel *tunnel = netdev_priv(dev); 1050 const struct iphdr *tiph = &tunnel->parms.iph; 1051 1052 if (iptunnel_handle_offloads(skb, SKB_GSO_IPXIP4)) 1053 goto tx_error; 1054 1055 skb_set_inner_ipproto(skb, ipproto); 1056 1057 ip_tunnel_xmit(skb, dev, tiph, ipproto); 1058 return NETDEV_TX_OK; 1059 tx_error: 1060 kfree_skb(skb); 1061 DEV_STATS_INC(dev, tx_errors); 1062 return NETDEV_TX_OK; 1063 } 1064 1065 static netdev_tx_t sit_tunnel_xmit(struct sk_buff *skb, 1066 struct net_device *dev) 1067 { 1068 if (!pskb_inet_may_pull(skb)) 1069 goto tx_err; 1070 1071 switch (skb->protocol) { 1072 case htons(ETH_P_IP): 1073 sit_tunnel_xmit__(skb, dev, IPPROTO_IPIP); 1074 break; 1075 case htons(ETH_P_IPV6): 1076 ipip6_tunnel_xmit(skb, dev); 1077 break; 1078 #if IS_ENABLED(CONFIG_MPLS) 1079 case htons(ETH_P_MPLS_UC): 1080 sit_tunnel_xmit__(skb, dev, IPPROTO_MPLS); 1081 break; 1082 #endif 1083 default: 1084 goto tx_err; 1085 } 1086 1087 return NETDEV_TX_OK; 1088 1089 tx_err: 1090 DEV_STATS_INC(dev, tx_errors); 1091 kfree_skb(skb); 1092 return NETDEV_TX_OK; 1093 1094 } 1095 1096 static void ipip6_tunnel_bind_dev(struct net_device *dev) 1097 { 1098 struct net_device *tdev = NULL; 1099 struct ip_tunnel *tunnel; 1100 const struct iphdr *iph; 1101 struct flowi4 fl4; 1102 1103 tunnel = netdev_priv(dev); 1104 iph = &tunnel->parms.iph; 1105 1106 if (iph->daddr) { 1107 struct rtable *rt = ip_route_output_ports(tunnel->net, &fl4, 1108 NULL, 1109 iph->daddr, iph->saddr, 1110 0, 0, 1111 IPPROTO_IPV6, 1112 RT_TOS(iph->tos), 1113 tunnel->parms.link); 1114 1115 if (!IS_ERR(rt)) { 1116 tdev = rt->dst.dev; 1117 ip_rt_put(rt); 1118 } 1119 dev->flags |= IFF_POINTOPOINT; 1120 } 1121 1122 if (!tdev && tunnel->parms.link) 1123 tdev = __dev_get_by_index(tunnel->net, tunnel->parms.link); 1124 1125 if (tdev && !netif_is_l3_master(tdev)) { 1126 int t_hlen = tunnel->hlen + sizeof(struct iphdr); 1127 int mtu; 1128 1129 mtu = tdev->mtu - t_hlen; 1130 if (mtu < IPV6_MIN_MTU) 1131 mtu = IPV6_MIN_MTU; 1132 WRITE_ONCE(dev->mtu, mtu); 1133 } 1134 } 1135 1136 static void ipip6_tunnel_update(struct ip_tunnel *t, struct ip_tunnel_parm *p, 1137 __u32 fwmark) 1138 { 1139 struct net *net = t->net; 1140 struct sit_net *sitn = net_generic(net, sit_net_id); 1141 1142 ipip6_tunnel_unlink(sitn, t); 1143 synchronize_net(); 1144 t->parms.iph.saddr = p->iph.saddr; 1145 t->parms.iph.daddr = p->iph.daddr; 1146 __dev_addr_set(t->dev, &p->iph.saddr, 4); 1147 memcpy(t->dev->broadcast, &p->iph.daddr, 4); 1148 ipip6_tunnel_link(sitn, t); 1149 t->parms.iph.ttl = p->iph.ttl; 1150 t->parms.iph.tos = p->iph.tos; 1151 t->parms.iph.frag_off = p->iph.frag_off; 1152 if (t->parms.link != p->link || t->fwmark != fwmark) { 1153 t->parms.link = p->link; 1154 t->fwmark = fwmark; 1155 ipip6_tunnel_bind_dev(t->dev); 1156 } 1157 dst_cache_reset(&t->dst_cache); 1158 netdev_state_change(t->dev); 1159 } 1160 1161 #ifdef CONFIG_IPV6_SIT_6RD 1162 static int ipip6_tunnel_update_6rd(struct ip_tunnel *t, 1163 struct ip_tunnel_6rd *ip6rd) 1164 { 1165 struct in6_addr prefix; 1166 __be32 relay_prefix; 1167 1168 if (ip6rd->relay_prefixlen > 32 || 1169 ip6rd->prefixlen + (32 - ip6rd->relay_prefixlen) > 64) 1170 return -EINVAL; 1171 1172 ipv6_addr_prefix(&prefix, &ip6rd->prefix, ip6rd->prefixlen); 1173 if (!ipv6_addr_equal(&prefix, &ip6rd->prefix)) 1174 return -EINVAL; 1175 if (ip6rd->relay_prefixlen) 1176 relay_prefix = ip6rd->relay_prefix & 1177 htonl(0xffffffffUL << 1178 (32 - ip6rd->relay_prefixlen)); 1179 else 1180 relay_prefix = 0; 1181 if (relay_prefix != ip6rd->relay_prefix) 1182 return -EINVAL; 1183 1184 t->ip6rd.prefix = prefix; 1185 t->ip6rd.relay_prefix = relay_prefix; 1186 t->ip6rd.prefixlen = ip6rd->prefixlen; 1187 t->ip6rd.relay_prefixlen = ip6rd->relay_prefixlen; 1188 dst_cache_reset(&t->dst_cache); 1189 netdev_state_change(t->dev); 1190 return 0; 1191 } 1192 1193 static int 1194 ipip6_tunnel_get6rd(struct net_device *dev, struct ip_tunnel_parm __user *data) 1195 { 1196 struct ip_tunnel *t = netdev_priv(dev); 1197 struct ip_tunnel_6rd ip6rd; 1198 struct ip_tunnel_parm p; 1199 1200 if (dev == dev_to_sit_net(dev)->fb_tunnel_dev) { 1201 if (copy_from_user(&p, data, sizeof(p))) 1202 return -EFAULT; 1203 t = ipip6_tunnel_locate(t->net, &p, 0); 1204 } 1205 if (!t) 1206 t = netdev_priv(dev); 1207 1208 ip6rd.prefix = t->ip6rd.prefix; 1209 ip6rd.relay_prefix = t->ip6rd.relay_prefix; 1210 ip6rd.prefixlen = t->ip6rd.prefixlen; 1211 ip6rd.relay_prefixlen = t->ip6rd.relay_prefixlen; 1212 if (copy_to_user(data, &ip6rd, sizeof(ip6rd))) 1213 return -EFAULT; 1214 return 0; 1215 } 1216 1217 static int 1218 ipip6_tunnel_6rdctl(struct net_device *dev, struct ip_tunnel_6rd __user *data, 1219 int cmd) 1220 { 1221 struct ip_tunnel *t = netdev_priv(dev); 1222 struct ip_tunnel_6rd ip6rd; 1223 int err; 1224 1225 if (!ns_capable(t->net->user_ns, CAP_NET_ADMIN)) 1226 return -EPERM; 1227 if (copy_from_user(&ip6rd, data, sizeof(ip6rd))) 1228 return -EFAULT; 1229 1230 if (cmd != SIOCDEL6RD) { 1231 err = ipip6_tunnel_update_6rd(t, &ip6rd); 1232 if (err < 0) 1233 return err; 1234 } else 1235 ipip6_tunnel_clone_6rd(dev, dev_to_sit_net(dev)); 1236 return 0; 1237 } 1238 1239 #endif /* CONFIG_IPV6_SIT_6RD */ 1240 1241 static bool ipip6_valid_ip_proto(u8 ipproto) 1242 { 1243 return ipproto == IPPROTO_IPV6 || 1244 ipproto == IPPROTO_IPIP || 1245 #if IS_ENABLED(CONFIG_MPLS) 1246 ipproto == IPPROTO_MPLS || 1247 #endif 1248 ipproto == 0; 1249 } 1250 1251 static int 1252 __ipip6_tunnel_ioctl_validate(struct net *net, struct ip_tunnel_parm *p) 1253 { 1254 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 1255 return -EPERM; 1256 1257 if (!ipip6_valid_ip_proto(p->iph.protocol)) 1258 return -EINVAL; 1259 if (p->iph.version != 4 || 1260 p->iph.ihl != 5 || (p->iph.frag_off & htons(~IP_DF))) 1261 return -EINVAL; 1262 1263 if (p->iph.ttl) 1264 p->iph.frag_off |= htons(IP_DF); 1265 return 0; 1266 } 1267 1268 static int 1269 ipip6_tunnel_get(struct net_device *dev, struct ip_tunnel_parm *p) 1270 { 1271 struct ip_tunnel *t = netdev_priv(dev); 1272 1273 if (dev == dev_to_sit_net(dev)->fb_tunnel_dev) 1274 t = ipip6_tunnel_locate(t->net, p, 0); 1275 if (!t) 1276 t = netdev_priv(dev); 1277 memcpy(p, &t->parms, sizeof(*p)); 1278 return 0; 1279 } 1280 1281 static int 1282 ipip6_tunnel_add(struct net_device *dev, struct ip_tunnel_parm *p) 1283 { 1284 struct ip_tunnel *t = netdev_priv(dev); 1285 int err; 1286 1287 err = __ipip6_tunnel_ioctl_validate(t->net, p); 1288 if (err) 1289 return err; 1290 1291 t = ipip6_tunnel_locate(t->net, p, 1); 1292 if (!t) 1293 return -ENOBUFS; 1294 return 0; 1295 } 1296 1297 static int 1298 ipip6_tunnel_change(struct net_device *dev, struct ip_tunnel_parm *p) 1299 { 1300 struct ip_tunnel *t = netdev_priv(dev); 1301 int err; 1302 1303 err = __ipip6_tunnel_ioctl_validate(t->net, p); 1304 if (err) 1305 return err; 1306 1307 t = ipip6_tunnel_locate(t->net, p, 0); 1308 if (dev == dev_to_sit_net(dev)->fb_tunnel_dev) { 1309 if (!t) 1310 return -ENOENT; 1311 } else { 1312 if (t) { 1313 if (t->dev != dev) 1314 return -EEXIST; 1315 } else { 1316 if (((dev->flags & IFF_POINTOPOINT) && !p->iph.daddr) || 1317 (!(dev->flags & IFF_POINTOPOINT) && p->iph.daddr)) 1318 return -EINVAL; 1319 t = netdev_priv(dev); 1320 } 1321 1322 ipip6_tunnel_update(t, p, t->fwmark); 1323 } 1324 1325 return 0; 1326 } 1327 1328 static int 1329 ipip6_tunnel_del(struct net_device *dev, struct ip_tunnel_parm *p) 1330 { 1331 struct ip_tunnel *t = netdev_priv(dev); 1332 1333 if (!ns_capable(t->net->user_ns, CAP_NET_ADMIN)) 1334 return -EPERM; 1335 1336 if (dev == dev_to_sit_net(dev)->fb_tunnel_dev) { 1337 t = ipip6_tunnel_locate(t->net, p, 0); 1338 if (!t) 1339 return -ENOENT; 1340 if (t == netdev_priv(dev_to_sit_net(dev)->fb_tunnel_dev)) 1341 return -EPERM; 1342 dev = t->dev; 1343 } 1344 unregister_netdevice(dev); 1345 return 0; 1346 } 1347 1348 static int 1349 ipip6_tunnel_ctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd) 1350 { 1351 switch (cmd) { 1352 case SIOCGETTUNNEL: 1353 return ipip6_tunnel_get(dev, p); 1354 case SIOCADDTUNNEL: 1355 return ipip6_tunnel_add(dev, p); 1356 case SIOCCHGTUNNEL: 1357 return ipip6_tunnel_change(dev, p); 1358 case SIOCDELTUNNEL: 1359 return ipip6_tunnel_del(dev, p); 1360 default: 1361 return -EINVAL; 1362 } 1363 } 1364 1365 static int 1366 ipip6_tunnel_siocdevprivate(struct net_device *dev, struct ifreq *ifr, 1367 void __user *data, int cmd) 1368 { 1369 switch (cmd) { 1370 case SIOCGETTUNNEL: 1371 case SIOCADDTUNNEL: 1372 case SIOCCHGTUNNEL: 1373 case SIOCDELTUNNEL: 1374 return ip_tunnel_siocdevprivate(dev, ifr, data, cmd); 1375 case SIOCGETPRL: 1376 return ipip6_tunnel_get_prl(dev, data); 1377 case SIOCADDPRL: 1378 case SIOCDELPRL: 1379 case SIOCCHGPRL: 1380 return ipip6_tunnel_prl_ctl(dev, data, cmd); 1381 #ifdef CONFIG_IPV6_SIT_6RD 1382 case SIOCGET6RD: 1383 return ipip6_tunnel_get6rd(dev, data); 1384 case SIOCADD6RD: 1385 case SIOCCHG6RD: 1386 case SIOCDEL6RD: 1387 return ipip6_tunnel_6rdctl(dev, data, cmd); 1388 #endif 1389 default: 1390 return -EINVAL; 1391 } 1392 } 1393 1394 static const struct net_device_ops ipip6_netdev_ops = { 1395 .ndo_init = ipip6_tunnel_init, 1396 .ndo_uninit = ipip6_tunnel_uninit, 1397 .ndo_start_xmit = sit_tunnel_xmit, 1398 .ndo_siocdevprivate = ipip6_tunnel_siocdevprivate, 1399 .ndo_get_stats64 = dev_get_tstats64, 1400 .ndo_get_iflink = ip_tunnel_get_iflink, 1401 .ndo_tunnel_ctl = ipip6_tunnel_ctl, 1402 }; 1403 1404 static void ipip6_dev_free(struct net_device *dev) 1405 { 1406 struct ip_tunnel *tunnel = netdev_priv(dev); 1407 1408 dst_cache_destroy(&tunnel->dst_cache); 1409 free_percpu(dev->tstats); 1410 } 1411 1412 #define SIT_FEATURES (NETIF_F_SG | \ 1413 NETIF_F_FRAGLIST | \ 1414 NETIF_F_HIGHDMA | \ 1415 NETIF_F_GSO_SOFTWARE | \ 1416 NETIF_F_HW_CSUM) 1417 1418 static void ipip6_tunnel_setup(struct net_device *dev) 1419 { 1420 struct ip_tunnel *tunnel = netdev_priv(dev); 1421 int t_hlen = tunnel->hlen + sizeof(struct iphdr); 1422 1423 dev->netdev_ops = &ipip6_netdev_ops; 1424 dev->header_ops = &ip_tunnel_header_ops; 1425 dev->needs_free_netdev = true; 1426 dev->priv_destructor = ipip6_dev_free; 1427 1428 dev->type = ARPHRD_SIT; 1429 dev->mtu = ETH_DATA_LEN - t_hlen; 1430 dev->min_mtu = IPV6_MIN_MTU; 1431 dev->max_mtu = IP6_MAX_MTU - t_hlen; 1432 dev->flags = IFF_NOARP; 1433 netif_keep_dst(dev); 1434 dev->addr_len = 4; 1435 dev->features |= NETIF_F_LLTX; 1436 dev->features |= SIT_FEATURES; 1437 dev->hw_features |= SIT_FEATURES; 1438 } 1439 1440 static int ipip6_tunnel_init(struct net_device *dev) 1441 { 1442 struct ip_tunnel *tunnel = netdev_priv(dev); 1443 int err; 1444 1445 tunnel->dev = dev; 1446 tunnel->net = dev_net(dev); 1447 strcpy(tunnel->parms.name, dev->name); 1448 1449 ipip6_tunnel_bind_dev(dev); 1450 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats); 1451 if (!dev->tstats) 1452 return -ENOMEM; 1453 1454 err = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL); 1455 if (err) { 1456 free_percpu(dev->tstats); 1457 dev->tstats = NULL; 1458 return err; 1459 } 1460 netdev_hold(dev, &tunnel->dev_tracker, GFP_KERNEL); 1461 return 0; 1462 } 1463 1464 static void __net_init ipip6_fb_tunnel_init(struct net_device *dev) 1465 { 1466 struct ip_tunnel *tunnel = netdev_priv(dev); 1467 struct iphdr *iph = &tunnel->parms.iph; 1468 struct net *net = dev_net(dev); 1469 struct sit_net *sitn = net_generic(net, sit_net_id); 1470 1471 iph->version = 4; 1472 iph->protocol = IPPROTO_IPV6; 1473 iph->ihl = 5; 1474 iph->ttl = 64; 1475 1476 rcu_assign_pointer(sitn->tunnels_wc[0], tunnel); 1477 } 1478 1479 static int ipip6_validate(struct nlattr *tb[], struct nlattr *data[], 1480 struct netlink_ext_ack *extack) 1481 { 1482 u8 proto; 1483 1484 if (!data || !data[IFLA_IPTUN_PROTO]) 1485 return 0; 1486 1487 proto = nla_get_u8(data[IFLA_IPTUN_PROTO]); 1488 if (!ipip6_valid_ip_proto(proto)) 1489 return -EINVAL; 1490 1491 return 0; 1492 } 1493 1494 static void ipip6_netlink_parms(struct nlattr *data[], 1495 struct ip_tunnel_parm *parms, 1496 __u32 *fwmark) 1497 { 1498 memset(parms, 0, sizeof(*parms)); 1499 1500 parms->iph.version = 4; 1501 parms->iph.protocol = IPPROTO_IPV6; 1502 parms->iph.ihl = 5; 1503 parms->iph.ttl = 64; 1504 1505 if (!data) 1506 return; 1507 1508 ip_tunnel_netlink_parms(data, parms); 1509 1510 if (data[IFLA_IPTUN_FWMARK]) 1511 *fwmark = nla_get_u32(data[IFLA_IPTUN_FWMARK]); 1512 } 1513 1514 #ifdef CONFIG_IPV6_SIT_6RD 1515 /* This function returns true when 6RD attributes are present in the nl msg */ 1516 static bool ipip6_netlink_6rd_parms(struct nlattr *data[], 1517 struct ip_tunnel_6rd *ip6rd) 1518 { 1519 bool ret = false; 1520 memset(ip6rd, 0, sizeof(*ip6rd)); 1521 1522 if (!data) 1523 return ret; 1524 1525 if (data[IFLA_IPTUN_6RD_PREFIX]) { 1526 ret = true; 1527 ip6rd->prefix = nla_get_in6_addr(data[IFLA_IPTUN_6RD_PREFIX]); 1528 } 1529 1530 if (data[IFLA_IPTUN_6RD_RELAY_PREFIX]) { 1531 ret = true; 1532 ip6rd->relay_prefix = 1533 nla_get_be32(data[IFLA_IPTUN_6RD_RELAY_PREFIX]); 1534 } 1535 1536 if (data[IFLA_IPTUN_6RD_PREFIXLEN]) { 1537 ret = true; 1538 ip6rd->prefixlen = nla_get_u16(data[IFLA_IPTUN_6RD_PREFIXLEN]); 1539 } 1540 1541 if (data[IFLA_IPTUN_6RD_RELAY_PREFIXLEN]) { 1542 ret = true; 1543 ip6rd->relay_prefixlen = 1544 nla_get_u16(data[IFLA_IPTUN_6RD_RELAY_PREFIXLEN]); 1545 } 1546 1547 return ret; 1548 } 1549 #endif 1550 1551 static int ipip6_newlink(struct net *src_net, struct net_device *dev, 1552 struct nlattr *tb[], struct nlattr *data[], 1553 struct netlink_ext_ack *extack) 1554 { 1555 struct net *net = dev_net(dev); 1556 struct ip_tunnel *nt; 1557 struct ip_tunnel_encap ipencap; 1558 #ifdef CONFIG_IPV6_SIT_6RD 1559 struct ip_tunnel_6rd ip6rd; 1560 #endif 1561 int err; 1562 1563 nt = netdev_priv(dev); 1564 1565 if (ip_tunnel_netlink_encap_parms(data, &ipencap)) { 1566 err = ip_tunnel_encap_setup(nt, &ipencap); 1567 if (err < 0) 1568 return err; 1569 } 1570 1571 ipip6_netlink_parms(data, &nt->parms, &nt->fwmark); 1572 1573 if (ipip6_tunnel_locate(net, &nt->parms, 0)) 1574 return -EEXIST; 1575 1576 err = ipip6_tunnel_create(dev); 1577 if (err < 0) 1578 return err; 1579 1580 if (tb[IFLA_MTU]) { 1581 u32 mtu = nla_get_u32(tb[IFLA_MTU]); 1582 1583 if (mtu >= IPV6_MIN_MTU && 1584 mtu <= IP6_MAX_MTU - dev->hard_header_len) 1585 dev->mtu = mtu; 1586 } 1587 1588 #ifdef CONFIG_IPV6_SIT_6RD 1589 if (ipip6_netlink_6rd_parms(data, &ip6rd)) { 1590 err = ipip6_tunnel_update_6rd(nt, &ip6rd); 1591 if (err < 0) 1592 unregister_netdevice_queue(dev, NULL); 1593 } 1594 #endif 1595 1596 return err; 1597 } 1598 1599 static int ipip6_changelink(struct net_device *dev, struct nlattr *tb[], 1600 struct nlattr *data[], 1601 struct netlink_ext_ack *extack) 1602 { 1603 struct ip_tunnel *t = netdev_priv(dev); 1604 struct ip_tunnel_parm p; 1605 struct ip_tunnel_encap ipencap; 1606 struct net *net = t->net; 1607 struct sit_net *sitn = net_generic(net, sit_net_id); 1608 #ifdef CONFIG_IPV6_SIT_6RD 1609 struct ip_tunnel_6rd ip6rd; 1610 #endif 1611 __u32 fwmark = t->fwmark; 1612 int err; 1613 1614 if (dev == sitn->fb_tunnel_dev) 1615 return -EINVAL; 1616 1617 if (ip_tunnel_netlink_encap_parms(data, &ipencap)) { 1618 err = ip_tunnel_encap_setup(t, &ipencap); 1619 if (err < 0) 1620 return err; 1621 } 1622 1623 ipip6_netlink_parms(data, &p, &fwmark); 1624 1625 if (((dev->flags & IFF_POINTOPOINT) && !p.iph.daddr) || 1626 (!(dev->flags & IFF_POINTOPOINT) && p.iph.daddr)) 1627 return -EINVAL; 1628 1629 t = ipip6_tunnel_locate(net, &p, 0); 1630 1631 if (t) { 1632 if (t->dev != dev) 1633 return -EEXIST; 1634 } else 1635 t = netdev_priv(dev); 1636 1637 ipip6_tunnel_update(t, &p, fwmark); 1638 1639 #ifdef CONFIG_IPV6_SIT_6RD 1640 if (ipip6_netlink_6rd_parms(data, &ip6rd)) 1641 return ipip6_tunnel_update_6rd(t, &ip6rd); 1642 #endif 1643 1644 return 0; 1645 } 1646 1647 static size_t ipip6_get_size(const struct net_device *dev) 1648 { 1649 return 1650 /* IFLA_IPTUN_LINK */ 1651 nla_total_size(4) + 1652 /* IFLA_IPTUN_LOCAL */ 1653 nla_total_size(4) + 1654 /* IFLA_IPTUN_REMOTE */ 1655 nla_total_size(4) + 1656 /* IFLA_IPTUN_TTL */ 1657 nla_total_size(1) + 1658 /* IFLA_IPTUN_TOS */ 1659 nla_total_size(1) + 1660 /* IFLA_IPTUN_PMTUDISC */ 1661 nla_total_size(1) + 1662 /* IFLA_IPTUN_FLAGS */ 1663 nla_total_size(2) + 1664 /* IFLA_IPTUN_PROTO */ 1665 nla_total_size(1) + 1666 #ifdef CONFIG_IPV6_SIT_6RD 1667 /* IFLA_IPTUN_6RD_PREFIX */ 1668 nla_total_size(sizeof(struct in6_addr)) + 1669 /* IFLA_IPTUN_6RD_RELAY_PREFIX */ 1670 nla_total_size(4) + 1671 /* IFLA_IPTUN_6RD_PREFIXLEN */ 1672 nla_total_size(2) + 1673 /* IFLA_IPTUN_6RD_RELAY_PREFIXLEN */ 1674 nla_total_size(2) + 1675 #endif 1676 /* IFLA_IPTUN_ENCAP_TYPE */ 1677 nla_total_size(2) + 1678 /* IFLA_IPTUN_ENCAP_FLAGS */ 1679 nla_total_size(2) + 1680 /* IFLA_IPTUN_ENCAP_SPORT */ 1681 nla_total_size(2) + 1682 /* IFLA_IPTUN_ENCAP_DPORT */ 1683 nla_total_size(2) + 1684 /* IFLA_IPTUN_FWMARK */ 1685 nla_total_size(4) + 1686 0; 1687 } 1688 1689 static int ipip6_fill_info(struct sk_buff *skb, const struct net_device *dev) 1690 { 1691 struct ip_tunnel *tunnel = netdev_priv(dev); 1692 struct ip_tunnel_parm *parm = &tunnel->parms; 1693 1694 if (nla_put_u32(skb, IFLA_IPTUN_LINK, parm->link) || 1695 nla_put_in_addr(skb, IFLA_IPTUN_LOCAL, parm->iph.saddr) || 1696 nla_put_in_addr(skb, IFLA_IPTUN_REMOTE, parm->iph.daddr) || 1697 nla_put_u8(skb, IFLA_IPTUN_TTL, parm->iph.ttl) || 1698 nla_put_u8(skb, IFLA_IPTUN_TOS, parm->iph.tos) || 1699 nla_put_u8(skb, IFLA_IPTUN_PMTUDISC, 1700 !!(parm->iph.frag_off & htons(IP_DF))) || 1701 nla_put_u8(skb, IFLA_IPTUN_PROTO, parm->iph.protocol) || 1702 nla_put_be16(skb, IFLA_IPTUN_FLAGS, parm->i_flags) || 1703 nla_put_u32(skb, IFLA_IPTUN_FWMARK, tunnel->fwmark)) 1704 goto nla_put_failure; 1705 1706 #ifdef CONFIG_IPV6_SIT_6RD 1707 if (nla_put_in6_addr(skb, IFLA_IPTUN_6RD_PREFIX, 1708 &tunnel->ip6rd.prefix) || 1709 nla_put_in_addr(skb, IFLA_IPTUN_6RD_RELAY_PREFIX, 1710 tunnel->ip6rd.relay_prefix) || 1711 nla_put_u16(skb, IFLA_IPTUN_6RD_PREFIXLEN, 1712 tunnel->ip6rd.prefixlen) || 1713 nla_put_u16(skb, IFLA_IPTUN_6RD_RELAY_PREFIXLEN, 1714 tunnel->ip6rd.relay_prefixlen)) 1715 goto nla_put_failure; 1716 #endif 1717 1718 if (nla_put_u16(skb, IFLA_IPTUN_ENCAP_TYPE, 1719 tunnel->encap.type) || 1720 nla_put_be16(skb, IFLA_IPTUN_ENCAP_SPORT, 1721 tunnel->encap.sport) || 1722 nla_put_be16(skb, IFLA_IPTUN_ENCAP_DPORT, 1723 tunnel->encap.dport) || 1724 nla_put_u16(skb, IFLA_IPTUN_ENCAP_FLAGS, 1725 tunnel->encap.flags)) 1726 goto nla_put_failure; 1727 1728 return 0; 1729 1730 nla_put_failure: 1731 return -EMSGSIZE; 1732 } 1733 1734 static const struct nla_policy ipip6_policy[IFLA_IPTUN_MAX + 1] = { 1735 [IFLA_IPTUN_LINK] = { .type = NLA_U32 }, 1736 [IFLA_IPTUN_LOCAL] = { .type = NLA_U32 }, 1737 [IFLA_IPTUN_REMOTE] = { .type = NLA_U32 }, 1738 [IFLA_IPTUN_TTL] = { .type = NLA_U8 }, 1739 [IFLA_IPTUN_TOS] = { .type = NLA_U8 }, 1740 [IFLA_IPTUN_PMTUDISC] = { .type = NLA_U8 }, 1741 [IFLA_IPTUN_FLAGS] = { .type = NLA_U16 }, 1742 [IFLA_IPTUN_PROTO] = { .type = NLA_U8 }, 1743 #ifdef CONFIG_IPV6_SIT_6RD 1744 [IFLA_IPTUN_6RD_PREFIX] = { .len = sizeof(struct in6_addr) }, 1745 [IFLA_IPTUN_6RD_RELAY_PREFIX] = { .type = NLA_U32 }, 1746 [IFLA_IPTUN_6RD_PREFIXLEN] = { .type = NLA_U16 }, 1747 [IFLA_IPTUN_6RD_RELAY_PREFIXLEN] = { .type = NLA_U16 }, 1748 #endif 1749 [IFLA_IPTUN_ENCAP_TYPE] = { .type = NLA_U16 }, 1750 [IFLA_IPTUN_ENCAP_FLAGS] = { .type = NLA_U16 }, 1751 [IFLA_IPTUN_ENCAP_SPORT] = { .type = NLA_U16 }, 1752 [IFLA_IPTUN_ENCAP_DPORT] = { .type = NLA_U16 }, 1753 [IFLA_IPTUN_FWMARK] = { .type = NLA_U32 }, 1754 }; 1755 1756 static void ipip6_dellink(struct net_device *dev, struct list_head *head) 1757 { 1758 struct net *net = dev_net(dev); 1759 struct sit_net *sitn = net_generic(net, sit_net_id); 1760 1761 if (dev != sitn->fb_tunnel_dev) 1762 unregister_netdevice_queue(dev, head); 1763 } 1764 1765 static struct rtnl_link_ops sit_link_ops __read_mostly = { 1766 .kind = "sit", 1767 .maxtype = IFLA_IPTUN_MAX, 1768 .policy = ipip6_policy, 1769 .priv_size = sizeof(struct ip_tunnel), 1770 .setup = ipip6_tunnel_setup, 1771 .validate = ipip6_validate, 1772 .newlink = ipip6_newlink, 1773 .changelink = ipip6_changelink, 1774 .get_size = ipip6_get_size, 1775 .fill_info = ipip6_fill_info, 1776 .dellink = ipip6_dellink, 1777 .get_link_net = ip_tunnel_get_link_net, 1778 }; 1779 1780 static struct xfrm_tunnel sit_handler __read_mostly = { 1781 .handler = ipip6_rcv, 1782 .err_handler = ipip6_err, 1783 .priority = 1, 1784 }; 1785 1786 static struct xfrm_tunnel ipip_handler __read_mostly = { 1787 .handler = ipip_rcv, 1788 .err_handler = ipip6_err, 1789 .priority = 2, 1790 }; 1791 1792 #if IS_ENABLED(CONFIG_MPLS) 1793 static struct xfrm_tunnel mplsip_handler __read_mostly = { 1794 .handler = mplsip_rcv, 1795 .err_handler = ipip6_err, 1796 .priority = 2, 1797 }; 1798 #endif 1799 1800 static void __net_exit sit_destroy_tunnels(struct net *net, 1801 struct list_head *head) 1802 { 1803 struct sit_net *sitn = net_generic(net, sit_net_id); 1804 struct net_device *dev, *aux; 1805 int prio; 1806 1807 for_each_netdev_safe(net, dev, aux) 1808 if (dev->rtnl_link_ops == &sit_link_ops) 1809 unregister_netdevice_queue(dev, head); 1810 1811 for (prio = 0; prio < 4; prio++) { 1812 int h; 1813 for (h = 0; h < (prio ? IP6_SIT_HASH_SIZE : 1); h++) { 1814 struct ip_tunnel *t; 1815 1816 t = rtnl_dereference(sitn->tunnels[prio][h]); 1817 while (t) { 1818 /* If dev is in the same netns, it has already 1819 * been added to the list by the previous loop. 1820 */ 1821 if (!net_eq(dev_net(t->dev), net)) 1822 unregister_netdevice_queue(t->dev, 1823 head); 1824 t = rtnl_dereference(t->next); 1825 } 1826 } 1827 } 1828 } 1829 1830 static int __net_init sit_init_net(struct net *net) 1831 { 1832 struct sit_net *sitn = net_generic(net, sit_net_id); 1833 struct ip_tunnel *t; 1834 int err; 1835 1836 sitn->tunnels[0] = sitn->tunnels_wc; 1837 sitn->tunnels[1] = sitn->tunnels_l; 1838 sitn->tunnels[2] = sitn->tunnels_r; 1839 sitn->tunnels[3] = sitn->tunnels_r_l; 1840 1841 if (!net_has_fallback_tunnels(net)) 1842 return 0; 1843 1844 sitn->fb_tunnel_dev = alloc_netdev(sizeof(struct ip_tunnel), "sit0", 1845 NET_NAME_UNKNOWN, 1846 ipip6_tunnel_setup); 1847 if (!sitn->fb_tunnel_dev) { 1848 err = -ENOMEM; 1849 goto err_alloc_dev; 1850 } 1851 dev_net_set(sitn->fb_tunnel_dev, net); 1852 sitn->fb_tunnel_dev->rtnl_link_ops = &sit_link_ops; 1853 /* FB netdevice is special: we have one, and only one per netns. 1854 * Allowing to move it to another netns is clearly unsafe. 1855 */ 1856 sitn->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL; 1857 1858 err = register_netdev(sitn->fb_tunnel_dev); 1859 if (err) 1860 goto err_reg_dev; 1861 1862 ipip6_tunnel_clone_6rd(sitn->fb_tunnel_dev, sitn); 1863 ipip6_fb_tunnel_init(sitn->fb_tunnel_dev); 1864 1865 t = netdev_priv(sitn->fb_tunnel_dev); 1866 1867 strcpy(t->parms.name, sitn->fb_tunnel_dev->name); 1868 return 0; 1869 1870 err_reg_dev: 1871 free_netdev(sitn->fb_tunnel_dev); 1872 err_alloc_dev: 1873 return err; 1874 } 1875 1876 static void __net_exit sit_exit_batch_net(struct list_head *net_list) 1877 { 1878 LIST_HEAD(list); 1879 struct net *net; 1880 1881 rtnl_lock(); 1882 list_for_each_entry(net, net_list, exit_list) 1883 sit_destroy_tunnels(net, &list); 1884 1885 unregister_netdevice_many(&list); 1886 rtnl_unlock(); 1887 } 1888 1889 static struct pernet_operations sit_net_ops = { 1890 .init = sit_init_net, 1891 .exit_batch = sit_exit_batch_net, 1892 .id = &sit_net_id, 1893 .size = sizeof(struct sit_net), 1894 }; 1895 1896 static void __exit sit_cleanup(void) 1897 { 1898 rtnl_link_unregister(&sit_link_ops); 1899 xfrm4_tunnel_deregister(&sit_handler, AF_INET6); 1900 xfrm4_tunnel_deregister(&ipip_handler, AF_INET); 1901 #if IS_ENABLED(CONFIG_MPLS) 1902 xfrm4_tunnel_deregister(&mplsip_handler, AF_MPLS); 1903 #endif 1904 1905 unregister_pernet_device(&sit_net_ops); 1906 rcu_barrier(); /* Wait for completion of call_rcu()'s */ 1907 } 1908 1909 static int __init sit_init(void) 1910 { 1911 int err; 1912 1913 pr_info("IPv6, IPv4 and MPLS over IPv4 tunneling driver\n"); 1914 1915 err = register_pernet_device(&sit_net_ops); 1916 if (err < 0) 1917 return err; 1918 err = xfrm4_tunnel_register(&sit_handler, AF_INET6); 1919 if (err < 0) { 1920 pr_info("%s: can't register ip6ip4\n", __func__); 1921 goto xfrm_tunnel_failed; 1922 } 1923 err = xfrm4_tunnel_register(&ipip_handler, AF_INET); 1924 if (err < 0) { 1925 pr_info("%s: can't register ip4ip4\n", __func__); 1926 goto xfrm_tunnel4_failed; 1927 } 1928 #if IS_ENABLED(CONFIG_MPLS) 1929 err = xfrm4_tunnel_register(&mplsip_handler, AF_MPLS); 1930 if (err < 0) { 1931 pr_info("%s: can't register mplsip\n", __func__); 1932 goto xfrm_tunnel_mpls_failed; 1933 } 1934 #endif 1935 err = rtnl_link_register(&sit_link_ops); 1936 if (err < 0) 1937 goto rtnl_link_failed; 1938 1939 out: 1940 return err; 1941 1942 rtnl_link_failed: 1943 #if IS_ENABLED(CONFIG_MPLS) 1944 xfrm4_tunnel_deregister(&mplsip_handler, AF_MPLS); 1945 xfrm_tunnel_mpls_failed: 1946 #endif 1947 xfrm4_tunnel_deregister(&ipip_handler, AF_INET); 1948 xfrm_tunnel4_failed: 1949 xfrm4_tunnel_deregister(&sit_handler, AF_INET6); 1950 xfrm_tunnel_failed: 1951 unregister_pernet_device(&sit_net_ops); 1952 goto out; 1953 } 1954 1955 module_init(sit_init); 1956 module_exit(sit_cleanup); 1957 MODULE_LICENSE("GPL"); 1958 MODULE_ALIAS_RTNL_LINK("sit"); 1959 MODULE_ALIAS_NETDEV("sit0"); 1960