1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * IPv6 tunneling device 4 * Linux INET6 implementation 5 * 6 * Authors: 7 * Ville Nuorvala <vnuorval@tcs.hut.fi> 8 * Yasuyuki Kozakai <kozakai@linux-ipv6.org> 9 * 10 * Based on: 11 * linux/net/ipv6/sit.c and linux/net/ipv4/ipip.c 12 * 13 * RFC 2473 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/sockios.h> 23 #include <linux/icmp.h> 24 #include <linux/if.h> 25 #include <linux/in.h> 26 #include <linux/ip.h> 27 #include <linux/net.h> 28 #include <linux/in6.h> 29 #include <linux/netdevice.h> 30 #include <linux/if_arp.h> 31 #include <linux/icmpv6.h> 32 #include <linux/init.h> 33 #include <linux/route.h> 34 #include <linux/rtnetlink.h> 35 #include <linux/netfilter_ipv6.h> 36 #include <linux/slab.h> 37 #include <linux/hash.h> 38 #include <linux/etherdevice.h> 39 40 #include <linux/uaccess.h> 41 #include <linux/atomic.h> 42 43 #include <net/icmp.h> 44 #include <net/ip.h> 45 #include <net/ip_tunnels.h> 46 #include <net/ipv6.h> 47 #include <net/ip6_route.h> 48 #include <net/addrconf.h> 49 #include <net/ip6_tunnel.h> 50 #include <net/xfrm.h> 51 #include <net/dsfield.h> 52 #include <net/inet_ecn.h> 53 #include <net/net_namespace.h> 54 #include <net/netns/generic.h> 55 #include <net/dst_metadata.h> 56 57 MODULE_AUTHOR("Ville Nuorvala"); 58 MODULE_DESCRIPTION("IPv6 tunneling device"); 59 MODULE_LICENSE("GPL"); 60 MODULE_ALIAS_RTNL_LINK("ip6tnl"); 61 MODULE_ALIAS_NETDEV("ip6tnl0"); 62 63 #define IP6_TUNNEL_HASH_SIZE_SHIFT 5 64 #define IP6_TUNNEL_HASH_SIZE (1 << IP6_TUNNEL_HASH_SIZE_SHIFT) 65 66 static bool log_ecn_error = true; 67 module_param(log_ecn_error, bool, 0644); 68 MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN"); 69 70 static u32 HASH(const struct in6_addr *addr1, const struct in6_addr *addr2) 71 { 72 u32 hash = ipv6_addr_hash(addr1) ^ ipv6_addr_hash(addr2); 73 74 return hash_32(hash, IP6_TUNNEL_HASH_SIZE_SHIFT); 75 } 76 77 static int ip6_tnl_dev_init(struct net_device *dev); 78 static void ip6_tnl_dev_setup(struct net_device *dev); 79 static struct rtnl_link_ops ip6_link_ops __read_mostly; 80 81 static unsigned int ip6_tnl_net_id __read_mostly; 82 struct ip6_tnl_net { 83 /* the IPv6 tunnel fallback device */ 84 struct net_device *fb_tnl_dev; 85 /* lists for storing tunnels in use */ 86 struct ip6_tnl __rcu *tnls_r_l[IP6_TUNNEL_HASH_SIZE]; 87 struct ip6_tnl __rcu *tnls_wc[1]; 88 struct ip6_tnl __rcu **tnls[2]; 89 struct ip6_tnl __rcu *collect_md_tun; 90 }; 91 92 static struct net_device_stats *ip6_get_stats(struct net_device *dev) 93 { 94 struct pcpu_sw_netstats tmp, sum = { 0 }; 95 int i; 96 97 for_each_possible_cpu(i) { 98 unsigned int start; 99 const struct pcpu_sw_netstats *tstats = 100 per_cpu_ptr(dev->tstats, i); 101 102 do { 103 start = u64_stats_fetch_begin_irq(&tstats->syncp); 104 tmp.rx_packets = tstats->rx_packets; 105 tmp.rx_bytes = tstats->rx_bytes; 106 tmp.tx_packets = tstats->tx_packets; 107 tmp.tx_bytes = tstats->tx_bytes; 108 } while (u64_stats_fetch_retry_irq(&tstats->syncp, start)); 109 110 sum.rx_packets += tmp.rx_packets; 111 sum.rx_bytes += tmp.rx_bytes; 112 sum.tx_packets += tmp.tx_packets; 113 sum.tx_bytes += tmp.tx_bytes; 114 } 115 dev->stats.rx_packets = sum.rx_packets; 116 dev->stats.rx_bytes = sum.rx_bytes; 117 dev->stats.tx_packets = sum.tx_packets; 118 dev->stats.tx_bytes = sum.tx_bytes; 119 return &dev->stats; 120 } 121 122 /** 123 * ip6_tnl_lookup - fetch tunnel matching the end-point addresses 124 * @link: ifindex of underlying interface 125 * @remote: the address of the tunnel exit-point 126 * @local: the address of the tunnel entry-point 127 * 128 * Return: 129 * tunnel matching given end-points if found, 130 * else fallback tunnel if its device is up, 131 * else %NULL 132 **/ 133 134 #define for_each_ip6_tunnel_rcu(start) \ 135 for (t = rcu_dereference(start); t; t = rcu_dereference(t->next)) 136 137 static struct ip6_tnl * 138 ip6_tnl_lookup(struct net *net, int link, 139 const struct in6_addr *remote, const struct in6_addr *local) 140 { 141 unsigned int hash = HASH(remote, local); 142 struct ip6_tnl *t, *cand = NULL; 143 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 144 struct in6_addr any; 145 146 for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) { 147 if (!ipv6_addr_equal(local, &t->parms.laddr) || 148 !ipv6_addr_equal(remote, &t->parms.raddr) || 149 !(t->dev->flags & IFF_UP)) 150 continue; 151 152 if (link == t->parms.link) 153 return t; 154 else 155 cand = t; 156 } 157 158 memset(&any, 0, sizeof(any)); 159 hash = HASH(&any, local); 160 for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) { 161 if (!ipv6_addr_equal(local, &t->parms.laddr) || 162 !ipv6_addr_any(&t->parms.raddr) || 163 !(t->dev->flags & IFF_UP)) 164 continue; 165 166 if (link == t->parms.link) 167 return t; 168 else if (!cand) 169 cand = t; 170 } 171 172 hash = HASH(remote, &any); 173 for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) { 174 if (!ipv6_addr_equal(remote, &t->parms.raddr) || 175 !ipv6_addr_any(&t->parms.laddr) || 176 !(t->dev->flags & IFF_UP)) 177 continue; 178 179 if (link == t->parms.link) 180 return t; 181 else if (!cand) 182 cand = t; 183 } 184 185 if (cand) 186 return cand; 187 188 t = rcu_dereference(ip6n->collect_md_tun); 189 if (t && t->dev->flags & IFF_UP) 190 return t; 191 192 t = rcu_dereference(ip6n->tnls_wc[0]); 193 if (t && (t->dev->flags & IFF_UP)) 194 return t; 195 196 return NULL; 197 } 198 199 /** 200 * ip6_tnl_bucket - get head of list matching given tunnel parameters 201 * @p: parameters containing tunnel end-points 202 * 203 * Description: 204 * ip6_tnl_bucket() returns the head of the list matching the 205 * &struct in6_addr entries laddr and raddr in @p. 206 * 207 * Return: head of IPv6 tunnel list 208 **/ 209 210 static struct ip6_tnl __rcu ** 211 ip6_tnl_bucket(struct ip6_tnl_net *ip6n, const struct __ip6_tnl_parm *p) 212 { 213 const struct in6_addr *remote = &p->raddr; 214 const struct in6_addr *local = &p->laddr; 215 unsigned int h = 0; 216 int prio = 0; 217 218 if (!ipv6_addr_any(remote) || !ipv6_addr_any(local)) { 219 prio = 1; 220 h = HASH(remote, local); 221 } 222 return &ip6n->tnls[prio][h]; 223 } 224 225 /** 226 * ip6_tnl_link - add tunnel to hash table 227 * @t: tunnel to be added 228 **/ 229 230 static void 231 ip6_tnl_link(struct ip6_tnl_net *ip6n, struct ip6_tnl *t) 232 { 233 struct ip6_tnl __rcu **tp = ip6_tnl_bucket(ip6n, &t->parms); 234 235 if (t->parms.collect_md) 236 rcu_assign_pointer(ip6n->collect_md_tun, t); 237 rcu_assign_pointer(t->next , rtnl_dereference(*tp)); 238 rcu_assign_pointer(*tp, t); 239 } 240 241 /** 242 * ip6_tnl_unlink - remove tunnel from hash table 243 * @t: tunnel to be removed 244 **/ 245 246 static void 247 ip6_tnl_unlink(struct ip6_tnl_net *ip6n, struct ip6_tnl *t) 248 { 249 struct ip6_tnl __rcu **tp; 250 struct ip6_tnl *iter; 251 252 if (t->parms.collect_md) 253 rcu_assign_pointer(ip6n->collect_md_tun, NULL); 254 255 for (tp = ip6_tnl_bucket(ip6n, &t->parms); 256 (iter = rtnl_dereference(*tp)) != NULL; 257 tp = &iter->next) { 258 if (t == iter) { 259 rcu_assign_pointer(*tp, t->next); 260 break; 261 } 262 } 263 } 264 265 static void ip6_dev_free(struct net_device *dev) 266 { 267 struct ip6_tnl *t = netdev_priv(dev); 268 269 gro_cells_destroy(&t->gro_cells); 270 dst_cache_destroy(&t->dst_cache); 271 free_percpu(dev->tstats); 272 } 273 274 static int ip6_tnl_create2(struct net_device *dev) 275 { 276 struct ip6_tnl *t = netdev_priv(dev); 277 struct net *net = dev_net(dev); 278 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 279 int err; 280 281 t = netdev_priv(dev); 282 283 dev->rtnl_link_ops = &ip6_link_ops; 284 err = register_netdevice(dev); 285 if (err < 0) 286 goto out; 287 288 strcpy(t->parms.name, dev->name); 289 290 dev_hold(dev); 291 ip6_tnl_link(ip6n, t); 292 return 0; 293 294 out: 295 return err; 296 } 297 298 /** 299 * ip6_tnl_create - create a new tunnel 300 * @p: tunnel parameters 301 * @pt: pointer to new tunnel 302 * 303 * Description: 304 * Create tunnel matching given parameters. 305 * 306 * Return: 307 * created tunnel or error pointer 308 **/ 309 310 static struct ip6_tnl *ip6_tnl_create(struct net *net, struct __ip6_tnl_parm *p) 311 { 312 struct net_device *dev; 313 struct ip6_tnl *t; 314 char name[IFNAMSIZ]; 315 int err = -E2BIG; 316 317 if (p->name[0]) { 318 if (!dev_valid_name(p->name)) 319 goto failed; 320 strlcpy(name, p->name, IFNAMSIZ); 321 } else { 322 sprintf(name, "ip6tnl%%d"); 323 } 324 err = -ENOMEM; 325 dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN, 326 ip6_tnl_dev_setup); 327 if (!dev) 328 goto failed; 329 330 dev_net_set(dev, net); 331 332 t = netdev_priv(dev); 333 t->parms = *p; 334 t->net = dev_net(dev); 335 err = ip6_tnl_create2(dev); 336 if (err < 0) 337 goto failed_free; 338 339 return t; 340 341 failed_free: 342 free_netdev(dev); 343 failed: 344 return ERR_PTR(err); 345 } 346 347 /** 348 * ip6_tnl_locate - find or create tunnel matching given parameters 349 * @p: tunnel parameters 350 * @create: != 0 if allowed to create new tunnel if no match found 351 * 352 * Description: 353 * ip6_tnl_locate() first tries to locate an existing tunnel 354 * based on @parms. If this is unsuccessful, but @create is set a new 355 * tunnel device is created and registered for use. 356 * 357 * Return: 358 * matching tunnel or error pointer 359 **/ 360 361 static struct ip6_tnl *ip6_tnl_locate(struct net *net, 362 struct __ip6_tnl_parm *p, int create) 363 { 364 const struct in6_addr *remote = &p->raddr; 365 const struct in6_addr *local = &p->laddr; 366 struct ip6_tnl __rcu **tp; 367 struct ip6_tnl *t; 368 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 369 370 for (tp = ip6_tnl_bucket(ip6n, p); 371 (t = rtnl_dereference(*tp)) != NULL; 372 tp = &t->next) { 373 if (ipv6_addr_equal(local, &t->parms.laddr) && 374 ipv6_addr_equal(remote, &t->parms.raddr) && 375 p->link == t->parms.link) { 376 if (create) 377 return ERR_PTR(-EEXIST); 378 379 return t; 380 } 381 } 382 if (!create) 383 return ERR_PTR(-ENODEV); 384 return ip6_tnl_create(net, p); 385 } 386 387 /** 388 * ip6_tnl_dev_uninit - tunnel device uninitializer 389 * @dev: the device to be destroyed 390 * 391 * Description: 392 * ip6_tnl_dev_uninit() removes tunnel from its list 393 **/ 394 395 static void 396 ip6_tnl_dev_uninit(struct net_device *dev) 397 { 398 struct ip6_tnl *t = netdev_priv(dev); 399 struct net *net = t->net; 400 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 401 402 if (dev == ip6n->fb_tnl_dev) 403 RCU_INIT_POINTER(ip6n->tnls_wc[0], NULL); 404 else 405 ip6_tnl_unlink(ip6n, t); 406 dst_cache_reset(&t->dst_cache); 407 dev_put(dev); 408 } 409 410 /** 411 * parse_tvl_tnl_enc_lim - handle encapsulation limit option 412 * @skb: received socket buffer 413 * 414 * Return: 415 * 0 if none was found, 416 * else index to encapsulation limit 417 **/ 418 419 __u16 ip6_tnl_parse_tlv_enc_lim(struct sk_buff *skb, __u8 *raw) 420 { 421 const struct ipv6hdr *ipv6h = (const struct ipv6hdr *)raw; 422 unsigned int nhoff = raw - skb->data; 423 unsigned int off = nhoff + sizeof(*ipv6h); 424 u8 next, nexthdr = ipv6h->nexthdr; 425 426 while (ipv6_ext_hdr(nexthdr) && nexthdr != NEXTHDR_NONE) { 427 struct ipv6_opt_hdr *hdr; 428 u16 optlen; 429 430 if (!pskb_may_pull(skb, off + sizeof(*hdr))) 431 break; 432 433 hdr = (struct ipv6_opt_hdr *)(skb->data + off); 434 if (nexthdr == NEXTHDR_FRAGMENT) { 435 struct frag_hdr *frag_hdr = (struct frag_hdr *) hdr; 436 if (frag_hdr->frag_off) 437 break; 438 optlen = 8; 439 } else if (nexthdr == NEXTHDR_AUTH) { 440 optlen = ipv6_authlen(hdr); 441 } else { 442 optlen = ipv6_optlen(hdr); 443 } 444 /* cache hdr->nexthdr, since pskb_may_pull() might 445 * invalidate hdr 446 */ 447 next = hdr->nexthdr; 448 if (nexthdr == NEXTHDR_DEST) { 449 u16 i = 2; 450 451 /* Remember : hdr is no longer valid at this point. */ 452 if (!pskb_may_pull(skb, off + optlen)) 453 break; 454 455 while (1) { 456 struct ipv6_tlv_tnl_enc_lim *tel; 457 458 /* No more room for encapsulation limit */ 459 if (i + sizeof(*tel) > optlen) 460 break; 461 462 tel = (struct ipv6_tlv_tnl_enc_lim *)(skb->data + off + i); 463 /* return index of option if found and valid */ 464 if (tel->type == IPV6_TLV_TNL_ENCAP_LIMIT && 465 tel->length == 1) 466 return i + off - nhoff; 467 /* else jump to next option */ 468 if (tel->type) 469 i += tel->length + 2; 470 else 471 i++; 472 } 473 } 474 nexthdr = next; 475 off += optlen; 476 } 477 return 0; 478 } 479 EXPORT_SYMBOL(ip6_tnl_parse_tlv_enc_lim); 480 481 /** 482 * ip6_tnl_err - tunnel error handler 483 * 484 * Description: 485 * ip6_tnl_err() should handle errors in the tunnel according 486 * to the specifications in RFC 2473. 487 **/ 488 489 static int 490 ip6_tnl_err(struct sk_buff *skb, __u8 ipproto, struct inet6_skb_parm *opt, 491 u8 *type, u8 *code, int *msg, __u32 *info, int offset) 492 { 493 const struct ipv6hdr *ipv6h = (const struct ipv6hdr *)skb->data; 494 struct net *net = dev_net(skb->dev); 495 u8 rel_type = ICMPV6_DEST_UNREACH; 496 u8 rel_code = ICMPV6_ADDR_UNREACH; 497 __u32 rel_info = 0; 498 struct ip6_tnl *t; 499 int err = -ENOENT; 500 int rel_msg = 0; 501 u8 tproto; 502 __u16 len; 503 504 /* If the packet doesn't contain the original IPv6 header we are 505 in trouble since we might need the source address for further 506 processing of the error. */ 507 508 rcu_read_lock(); 509 t = ip6_tnl_lookup(dev_net(skb->dev), skb->dev->ifindex, &ipv6h->daddr, &ipv6h->saddr); 510 if (!t) 511 goto out; 512 513 tproto = READ_ONCE(t->parms.proto); 514 if (tproto != ipproto && tproto != 0) 515 goto out; 516 517 err = 0; 518 519 switch (*type) { 520 case ICMPV6_DEST_UNREACH: 521 net_dbg_ratelimited("%s: Path to destination invalid or inactive!\n", 522 t->parms.name); 523 rel_msg = 1; 524 break; 525 case ICMPV6_TIME_EXCEED: 526 if ((*code) == ICMPV6_EXC_HOPLIMIT) { 527 net_dbg_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n", 528 t->parms.name); 529 rel_msg = 1; 530 } 531 break; 532 case ICMPV6_PARAMPROB: { 533 struct ipv6_tlv_tnl_enc_lim *tel; 534 __u32 teli; 535 536 teli = 0; 537 if ((*code) == ICMPV6_HDR_FIELD) 538 teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data); 539 540 if (teli && teli == *info - 2) { 541 tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli]; 542 if (tel->encap_limit == 0) { 543 net_dbg_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n", 544 t->parms.name); 545 rel_msg = 1; 546 } 547 } else { 548 net_dbg_ratelimited("%s: Recipient unable to parse tunneled packet!\n", 549 t->parms.name); 550 } 551 break; 552 } 553 case ICMPV6_PKT_TOOBIG: { 554 __u32 mtu; 555 556 ip6_update_pmtu(skb, net, htonl(*info), 0, 0, 557 sock_net_uid(net, NULL)); 558 mtu = *info - offset; 559 if (mtu < IPV6_MIN_MTU) 560 mtu = IPV6_MIN_MTU; 561 len = sizeof(*ipv6h) + ntohs(ipv6h->payload_len); 562 if (len > mtu) { 563 rel_type = ICMPV6_PKT_TOOBIG; 564 rel_code = 0; 565 rel_info = mtu; 566 rel_msg = 1; 567 } 568 break; 569 } 570 case NDISC_REDIRECT: 571 ip6_redirect(skb, net, skb->dev->ifindex, 0, 572 sock_net_uid(net, NULL)); 573 break; 574 } 575 576 *type = rel_type; 577 *code = rel_code; 578 *info = rel_info; 579 *msg = rel_msg; 580 581 out: 582 rcu_read_unlock(); 583 return err; 584 } 585 586 static int 587 ip4ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 588 u8 type, u8 code, int offset, __be32 info) 589 { 590 __u32 rel_info = ntohl(info); 591 const struct iphdr *eiph; 592 struct sk_buff *skb2; 593 int err, rel_msg = 0; 594 u8 rel_type = type; 595 u8 rel_code = code; 596 struct rtable *rt; 597 struct flowi4 fl4; 598 599 err = ip6_tnl_err(skb, IPPROTO_IPIP, opt, &rel_type, &rel_code, 600 &rel_msg, &rel_info, offset); 601 if (err < 0) 602 return err; 603 604 if (rel_msg == 0) 605 return 0; 606 607 switch (rel_type) { 608 case ICMPV6_DEST_UNREACH: 609 if (rel_code != ICMPV6_ADDR_UNREACH) 610 return 0; 611 rel_type = ICMP_DEST_UNREACH; 612 rel_code = ICMP_HOST_UNREACH; 613 break; 614 case ICMPV6_PKT_TOOBIG: 615 if (rel_code != 0) 616 return 0; 617 rel_type = ICMP_DEST_UNREACH; 618 rel_code = ICMP_FRAG_NEEDED; 619 break; 620 default: 621 return 0; 622 } 623 624 if (!pskb_may_pull(skb, offset + sizeof(struct iphdr))) 625 return 0; 626 627 skb2 = skb_clone(skb, GFP_ATOMIC); 628 if (!skb2) 629 return 0; 630 631 skb_dst_drop(skb2); 632 633 skb_pull(skb2, offset); 634 skb_reset_network_header(skb2); 635 eiph = ip_hdr(skb2); 636 637 /* Try to guess incoming interface */ 638 rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL, eiph->saddr, 639 0, 0, 0, IPPROTO_IPIP, RT_TOS(eiph->tos), 0); 640 if (IS_ERR(rt)) 641 goto out; 642 643 skb2->dev = rt->dst.dev; 644 ip_rt_put(rt); 645 646 /* route "incoming" packet */ 647 if (rt->rt_flags & RTCF_LOCAL) { 648 rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL, 649 eiph->daddr, eiph->saddr, 0, 0, 650 IPPROTO_IPIP, RT_TOS(eiph->tos), 0); 651 if (IS_ERR(rt) || rt->dst.dev->type != ARPHRD_TUNNEL6) { 652 if (!IS_ERR(rt)) 653 ip_rt_put(rt); 654 goto out; 655 } 656 skb_dst_set(skb2, &rt->dst); 657 } else { 658 if (ip_route_input(skb2, eiph->daddr, eiph->saddr, eiph->tos, 659 skb2->dev) || 660 skb_dst(skb2)->dev->type != ARPHRD_TUNNEL6) 661 goto out; 662 } 663 664 /* change mtu on this route */ 665 if (rel_type == ICMP_DEST_UNREACH && rel_code == ICMP_FRAG_NEEDED) { 666 if (rel_info > dst_mtu(skb_dst(skb2))) 667 goto out; 668 669 skb_dst_update_pmtu_no_confirm(skb2, rel_info); 670 } 671 672 icmp_send(skb2, rel_type, rel_code, htonl(rel_info)); 673 674 out: 675 kfree_skb(skb2); 676 return 0; 677 } 678 679 static int 680 ip6ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 681 u8 type, u8 code, int offset, __be32 info) 682 { 683 __u32 rel_info = ntohl(info); 684 int err, rel_msg = 0; 685 u8 rel_type = type; 686 u8 rel_code = code; 687 688 err = ip6_tnl_err(skb, IPPROTO_IPV6, opt, &rel_type, &rel_code, 689 &rel_msg, &rel_info, offset); 690 if (err < 0) 691 return err; 692 693 if (rel_msg && pskb_may_pull(skb, offset + sizeof(struct ipv6hdr))) { 694 struct rt6_info *rt; 695 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC); 696 697 if (!skb2) 698 return 0; 699 700 skb_dst_drop(skb2); 701 skb_pull(skb2, offset); 702 skb_reset_network_header(skb2); 703 704 /* Try to guess incoming interface */ 705 rt = rt6_lookup(dev_net(skb->dev), &ipv6_hdr(skb2)->saddr, 706 NULL, 0, skb2, 0); 707 708 if (rt && rt->dst.dev) 709 skb2->dev = rt->dst.dev; 710 711 icmpv6_send(skb2, rel_type, rel_code, rel_info); 712 713 ip6_rt_put(rt); 714 715 kfree_skb(skb2); 716 } 717 718 return 0; 719 } 720 721 static int ip4ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t, 722 const struct ipv6hdr *ipv6h, 723 struct sk_buff *skb) 724 { 725 __u8 dsfield = ipv6_get_dsfield(ipv6h) & ~INET_ECN_MASK; 726 727 if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY) 728 ipv4_change_dsfield(ip_hdr(skb), INET_ECN_MASK, dsfield); 729 730 return IP6_ECN_decapsulate(ipv6h, skb); 731 } 732 733 static int ip6ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t, 734 const struct ipv6hdr *ipv6h, 735 struct sk_buff *skb) 736 { 737 if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY) 738 ipv6_copy_dscp(ipv6_get_dsfield(ipv6h), ipv6_hdr(skb)); 739 740 return IP6_ECN_decapsulate(ipv6h, skb); 741 } 742 743 __u32 ip6_tnl_get_cap(struct ip6_tnl *t, 744 const struct in6_addr *laddr, 745 const struct in6_addr *raddr) 746 { 747 struct __ip6_tnl_parm *p = &t->parms; 748 int ltype = ipv6_addr_type(laddr); 749 int rtype = ipv6_addr_type(raddr); 750 __u32 flags = 0; 751 752 if (ltype == IPV6_ADDR_ANY || rtype == IPV6_ADDR_ANY) { 753 flags = IP6_TNL_F_CAP_PER_PACKET; 754 } else if (ltype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) && 755 rtype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) && 756 !((ltype|rtype) & IPV6_ADDR_LOOPBACK) && 757 (!((ltype|rtype) & IPV6_ADDR_LINKLOCAL) || p->link)) { 758 if (ltype&IPV6_ADDR_UNICAST) 759 flags |= IP6_TNL_F_CAP_XMIT; 760 if (rtype&IPV6_ADDR_UNICAST) 761 flags |= IP6_TNL_F_CAP_RCV; 762 } 763 return flags; 764 } 765 EXPORT_SYMBOL(ip6_tnl_get_cap); 766 767 /* called with rcu_read_lock() */ 768 int ip6_tnl_rcv_ctl(struct ip6_tnl *t, 769 const struct in6_addr *laddr, 770 const struct in6_addr *raddr) 771 { 772 struct __ip6_tnl_parm *p = &t->parms; 773 int ret = 0; 774 struct net *net = t->net; 775 776 if ((p->flags & IP6_TNL_F_CAP_RCV) || 777 ((p->flags & IP6_TNL_F_CAP_PER_PACKET) && 778 (ip6_tnl_get_cap(t, laddr, raddr) & IP6_TNL_F_CAP_RCV))) { 779 struct net_device *ldev = NULL; 780 781 if (p->link) 782 ldev = dev_get_by_index_rcu(net, p->link); 783 784 if ((ipv6_addr_is_multicast(laddr) || 785 likely(ipv6_chk_addr_and_flags(net, laddr, ldev, false, 786 0, IFA_F_TENTATIVE))) && 787 ((p->flags & IP6_TNL_F_ALLOW_LOCAL_REMOTE) || 788 likely(!ipv6_chk_addr_and_flags(net, raddr, ldev, true, 789 0, IFA_F_TENTATIVE)))) 790 ret = 1; 791 } 792 return ret; 793 } 794 EXPORT_SYMBOL_GPL(ip6_tnl_rcv_ctl); 795 796 static int __ip6_tnl_rcv(struct ip6_tnl *tunnel, struct sk_buff *skb, 797 const struct tnl_ptk_info *tpi, 798 struct metadata_dst *tun_dst, 799 int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t, 800 const struct ipv6hdr *ipv6h, 801 struct sk_buff *skb), 802 bool log_ecn_err) 803 { 804 struct pcpu_sw_netstats *tstats; 805 const struct ipv6hdr *ipv6h = ipv6_hdr(skb); 806 int err; 807 808 if ((!(tpi->flags & TUNNEL_CSUM) && 809 (tunnel->parms.i_flags & TUNNEL_CSUM)) || 810 ((tpi->flags & TUNNEL_CSUM) && 811 !(tunnel->parms.i_flags & TUNNEL_CSUM))) { 812 tunnel->dev->stats.rx_crc_errors++; 813 tunnel->dev->stats.rx_errors++; 814 goto drop; 815 } 816 817 if (tunnel->parms.i_flags & TUNNEL_SEQ) { 818 if (!(tpi->flags & TUNNEL_SEQ) || 819 (tunnel->i_seqno && 820 (s32)(ntohl(tpi->seq) - tunnel->i_seqno) < 0)) { 821 tunnel->dev->stats.rx_fifo_errors++; 822 tunnel->dev->stats.rx_errors++; 823 goto drop; 824 } 825 tunnel->i_seqno = ntohl(tpi->seq) + 1; 826 } 827 828 skb->protocol = tpi->proto; 829 830 /* Warning: All skb pointers will be invalidated! */ 831 if (tunnel->dev->type == ARPHRD_ETHER) { 832 if (!pskb_may_pull(skb, ETH_HLEN)) { 833 tunnel->dev->stats.rx_length_errors++; 834 tunnel->dev->stats.rx_errors++; 835 goto drop; 836 } 837 838 ipv6h = ipv6_hdr(skb); 839 skb->protocol = eth_type_trans(skb, tunnel->dev); 840 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN); 841 } else { 842 skb->dev = tunnel->dev; 843 } 844 845 skb_reset_network_header(skb); 846 memset(skb->cb, 0, sizeof(struct inet6_skb_parm)); 847 848 __skb_tunnel_rx(skb, tunnel->dev, tunnel->net); 849 850 err = dscp_ecn_decapsulate(tunnel, ipv6h, skb); 851 if (unlikely(err)) { 852 if (log_ecn_err) 853 net_info_ratelimited("non-ECT from %pI6 with DS=%#x\n", 854 &ipv6h->saddr, 855 ipv6_get_dsfield(ipv6h)); 856 if (err > 1) { 857 ++tunnel->dev->stats.rx_frame_errors; 858 ++tunnel->dev->stats.rx_errors; 859 goto drop; 860 } 861 } 862 863 tstats = this_cpu_ptr(tunnel->dev->tstats); 864 u64_stats_update_begin(&tstats->syncp); 865 tstats->rx_packets++; 866 tstats->rx_bytes += skb->len; 867 u64_stats_update_end(&tstats->syncp); 868 869 skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(tunnel->dev))); 870 871 if (tun_dst) 872 skb_dst_set(skb, (struct dst_entry *)tun_dst); 873 874 gro_cells_receive(&tunnel->gro_cells, skb); 875 return 0; 876 877 drop: 878 if (tun_dst) 879 dst_release((struct dst_entry *)tun_dst); 880 kfree_skb(skb); 881 return 0; 882 } 883 884 int ip6_tnl_rcv(struct ip6_tnl *t, struct sk_buff *skb, 885 const struct tnl_ptk_info *tpi, 886 struct metadata_dst *tun_dst, 887 bool log_ecn_err) 888 { 889 return __ip6_tnl_rcv(t, skb, tpi, tun_dst, ip6ip6_dscp_ecn_decapsulate, 890 log_ecn_err); 891 } 892 EXPORT_SYMBOL(ip6_tnl_rcv); 893 894 static const struct tnl_ptk_info tpi_v6 = { 895 /* no tunnel info required for ipxip6. */ 896 .proto = htons(ETH_P_IPV6), 897 }; 898 899 static const struct tnl_ptk_info tpi_v4 = { 900 /* no tunnel info required for ipxip6. */ 901 .proto = htons(ETH_P_IP), 902 }; 903 904 static int ipxip6_rcv(struct sk_buff *skb, u8 ipproto, 905 const struct tnl_ptk_info *tpi, 906 int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t, 907 const struct ipv6hdr *ipv6h, 908 struct sk_buff *skb)) 909 { 910 struct ip6_tnl *t; 911 const struct ipv6hdr *ipv6h = ipv6_hdr(skb); 912 struct metadata_dst *tun_dst = NULL; 913 int ret = -1; 914 915 rcu_read_lock(); 916 t = ip6_tnl_lookup(dev_net(skb->dev), skb->dev->ifindex, &ipv6h->saddr, &ipv6h->daddr); 917 918 if (t) { 919 u8 tproto = READ_ONCE(t->parms.proto); 920 921 if (tproto != ipproto && tproto != 0) 922 goto drop; 923 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) 924 goto drop; 925 ipv6h = ipv6_hdr(skb); 926 if (!ip6_tnl_rcv_ctl(t, &ipv6h->daddr, &ipv6h->saddr)) 927 goto drop; 928 if (iptunnel_pull_header(skb, 0, tpi->proto, false)) 929 goto drop; 930 if (t->parms.collect_md) { 931 tun_dst = ipv6_tun_rx_dst(skb, 0, 0, 0); 932 if (!tun_dst) 933 goto drop; 934 } 935 ret = __ip6_tnl_rcv(t, skb, tpi, tun_dst, dscp_ecn_decapsulate, 936 log_ecn_error); 937 } 938 939 rcu_read_unlock(); 940 941 return ret; 942 943 drop: 944 rcu_read_unlock(); 945 kfree_skb(skb); 946 return 0; 947 } 948 949 static int ip4ip6_rcv(struct sk_buff *skb) 950 { 951 return ipxip6_rcv(skb, IPPROTO_IPIP, &tpi_v4, 952 ip4ip6_dscp_ecn_decapsulate); 953 } 954 955 static int ip6ip6_rcv(struct sk_buff *skb) 956 { 957 return ipxip6_rcv(skb, IPPROTO_IPV6, &tpi_v6, 958 ip6ip6_dscp_ecn_decapsulate); 959 } 960 961 struct ipv6_tel_txoption { 962 struct ipv6_txoptions ops; 963 __u8 dst_opt[8]; 964 }; 965 966 static void init_tel_txopt(struct ipv6_tel_txoption *opt, __u8 encap_limit) 967 { 968 memset(opt, 0, sizeof(struct ipv6_tel_txoption)); 969 970 opt->dst_opt[2] = IPV6_TLV_TNL_ENCAP_LIMIT; 971 opt->dst_opt[3] = 1; 972 opt->dst_opt[4] = encap_limit; 973 opt->dst_opt[5] = IPV6_TLV_PADN; 974 opt->dst_opt[6] = 1; 975 976 opt->ops.dst1opt = (struct ipv6_opt_hdr *) opt->dst_opt; 977 opt->ops.opt_nflen = 8; 978 } 979 980 /** 981 * ip6_tnl_addr_conflict - compare packet addresses to tunnel's own 982 * @t: the outgoing tunnel device 983 * @hdr: IPv6 header from the incoming packet 984 * 985 * Description: 986 * Avoid trivial tunneling loop by checking that tunnel exit-point 987 * doesn't match source of incoming packet. 988 * 989 * Return: 990 * 1 if conflict, 991 * 0 else 992 **/ 993 994 static inline bool 995 ip6_tnl_addr_conflict(const struct ip6_tnl *t, const struct ipv6hdr *hdr) 996 { 997 return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr); 998 } 999 1000 int ip6_tnl_xmit_ctl(struct ip6_tnl *t, 1001 const struct in6_addr *laddr, 1002 const struct in6_addr *raddr) 1003 { 1004 struct __ip6_tnl_parm *p = &t->parms; 1005 int ret = 0; 1006 struct net *net = t->net; 1007 1008 if (t->parms.collect_md) 1009 return 1; 1010 1011 if ((p->flags & IP6_TNL_F_CAP_XMIT) || 1012 ((p->flags & IP6_TNL_F_CAP_PER_PACKET) && 1013 (ip6_tnl_get_cap(t, laddr, raddr) & IP6_TNL_F_CAP_XMIT))) { 1014 struct net_device *ldev = NULL; 1015 1016 rcu_read_lock(); 1017 if (p->link) 1018 ldev = dev_get_by_index_rcu(net, p->link); 1019 1020 if (unlikely(!ipv6_chk_addr_and_flags(net, laddr, ldev, false, 1021 0, IFA_F_TENTATIVE))) 1022 pr_warn("%s xmit: Local address not yet configured!\n", 1023 p->name); 1024 else if (!(p->flags & IP6_TNL_F_ALLOW_LOCAL_REMOTE) && 1025 !ipv6_addr_is_multicast(raddr) && 1026 unlikely(ipv6_chk_addr_and_flags(net, raddr, ldev, 1027 true, 0, IFA_F_TENTATIVE))) 1028 pr_warn("%s xmit: Routing loop! Remote address found on this node!\n", 1029 p->name); 1030 else 1031 ret = 1; 1032 rcu_read_unlock(); 1033 } 1034 return ret; 1035 } 1036 EXPORT_SYMBOL_GPL(ip6_tnl_xmit_ctl); 1037 1038 /** 1039 * ip6_tnl_xmit - encapsulate packet and send 1040 * @skb: the outgoing socket buffer 1041 * @dev: the outgoing tunnel device 1042 * @dsfield: dscp code for outer header 1043 * @fl6: flow of tunneled packet 1044 * @encap_limit: encapsulation limit 1045 * @pmtu: Path MTU is stored if packet is too big 1046 * @proto: next header value 1047 * 1048 * Description: 1049 * Build new header and do some sanity checks on the packet before sending 1050 * it. 1051 * 1052 * Return: 1053 * 0 on success 1054 * -1 fail 1055 * %-EMSGSIZE message too big. return mtu in this case. 1056 **/ 1057 1058 int ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev, __u8 dsfield, 1059 struct flowi6 *fl6, int encap_limit, __u32 *pmtu, 1060 __u8 proto) 1061 { 1062 struct ip6_tnl *t = netdev_priv(dev); 1063 struct net *net = t->net; 1064 struct net_device_stats *stats = &t->dev->stats; 1065 struct ipv6hdr *ipv6h; 1066 struct ipv6_tel_txoption opt; 1067 struct dst_entry *dst = NULL, *ndst = NULL; 1068 struct net_device *tdev; 1069 int mtu; 1070 unsigned int eth_hlen = t->dev->type == ARPHRD_ETHER ? ETH_HLEN : 0; 1071 unsigned int psh_hlen = sizeof(struct ipv6hdr) + t->encap_hlen; 1072 unsigned int max_headroom = psh_hlen; 1073 bool use_cache = false; 1074 u8 hop_limit; 1075 int err = -1; 1076 1077 if (t->parms.collect_md) { 1078 hop_limit = skb_tunnel_info(skb)->key.ttl; 1079 goto route_lookup; 1080 } else { 1081 hop_limit = t->parms.hop_limit; 1082 } 1083 1084 /* NBMA tunnel */ 1085 if (ipv6_addr_any(&t->parms.raddr)) { 1086 if (skb->protocol == htons(ETH_P_IPV6)) { 1087 struct in6_addr *addr6; 1088 struct neighbour *neigh; 1089 int addr_type; 1090 1091 if (!skb_dst(skb)) 1092 goto tx_err_link_failure; 1093 1094 neigh = dst_neigh_lookup(skb_dst(skb), 1095 &ipv6_hdr(skb)->daddr); 1096 if (!neigh) 1097 goto tx_err_link_failure; 1098 1099 addr6 = (struct in6_addr *)&neigh->primary_key; 1100 addr_type = ipv6_addr_type(addr6); 1101 1102 if (addr_type == IPV6_ADDR_ANY) 1103 addr6 = &ipv6_hdr(skb)->daddr; 1104 1105 memcpy(&fl6->daddr, addr6, sizeof(fl6->daddr)); 1106 neigh_release(neigh); 1107 } 1108 } else if (t->parms.proto != 0 && !(t->parms.flags & 1109 (IP6_TNL_F_USE_ORIG_TCLASS | 1110 IP6_TNL_F_USE_ORIG_FWMARK))) { 1111 /* enable the cache only if neither the outer protocol nor the 1112 * routing decision depends on the current inner header value 1113 */ 1114 use_cache = true; 1115 } 1116 1117 if (use_cache) 1118 dst = dst_cache_get(&t->dst_cache); 1119 1120 if (!ip6_tnl_xmit_ctl(t, &fl6->saddr, &fl6->daddr)) 1121 goto tx_err_link_failure; 1122 1123 if (!dst) { 1124 route_lookup: 1125 /* add dsfield to flowlabel for route lookup */ 1126 fl6->flowlabel = ip6_make_flowinfo(dsfield, fl6->flowlabel); 1127 1128 dst = ip6_route_output(net, NULL, fl6); 1129 1130 if (dst->error) 1131 goto tx_err_link_failure; 1132 dst = xfrm_lookup(net, dst, flowi6_to_flowi(fl6), NULL, 0); 1133 if (IS_ERR(dst)) { 1134 err = PTR_ERR(dst); 1135 dst = NULL; 1136 goto tx_err_link_failure; 1137 } 1138 if (t->parms.collect_md && ipv6_addr_any(&fl6->saddr) && 1139 ipv6_dev_get_saddr(net, ip6_dst_idev(dst)->dev, 1140 &fl6->daddr, 0, &fl6->saddr)) 1141 goto tx_err_link_failure; 1142 ndst = dst; 1143 } 1144 1145 tdev = dst->dev; 1146 1147 if (tdev == dev) { 1148 stats->collisions++; 1149 net_warn_ratelimited("%s: Local routing loop detected!\n", 1150 t->parms.name); 1151 goto tx_err_dst_release; 1152 } 1153 mtu = dst_mtu(dst) - eth_hlen - psh_hlen - t->tun_hlen; 1154 if (encap_limit >= 0) { 1155 max_headroom += 8; 1156 mtu -= 8; 1157 } 1158 mtu = max(mtu, skb->protocol == htons(ETH_P_IPV6) ? 1159 IPV6_MIN_MTU : IPV4_MIN_MTU); 1160 1161 skb_dst_update_pmtu_no_confirm(skb, mtu); 1162 if (skb->len - t->tun_hlen - eth_hlen > mtu && !skb_is_gso(skb)) { 1163 *pmtu = mtu; 1164 err = -EMSGSIZE; 1165 goto tx_err_dst_release; 1166 } 1167 1168 if (t->err_count > 0) { 1169 if (time_before(jiffies, 1170 t->err_time + IP6TUNNEL_ERR_TIMEO)) { 1171 t->err_count--; 1172 1173 dst_link_failure(skb); 1174 } else { 1175 t->err_count = 0; 1176 } 1177 } 1178 1179 skb_scrub_packet(skb, !net_eq(t->net, dev_net(dev))); 1180 1181 /* 1182 * Okay, now see if we can stuff it in the buffer as-is. 1183 */ 1184 max_headroom += LL_RESERVED_SPACE(tdev); 1185 1186 if (skb_headroom(skb) < max_headroom || skb_shared(skb) || 1187 (skb_cloned(skb) && !skb_clone_writable(skb, 0))) { 1188 struct sk_buff *new_skb; 1189 1190 new_skb = skb_realloc_headroom(skb, max_headroom); 1191 if (!new_skb) 1192 goto tx_err_dst_release; 1193 1194 if (skb->sk) 1195 skb_set_owner_w(new_skb, skb->sk); 1196 consume_skb(skb); 1197 skb = new_skb; 1198 } 1199 1200 if (t->parms.collect_md) { 1201 if (t->encap.type != TUNNEL_ENCAP_NONE) 1202 goto tx_err_dst_release; 1203 } else { 1204 if (use_cache && ndst) 1205 dst_cache_set_ip6(&t->dst_cache, ndst, &fl6->saddr); 1206 } 1207 skb_dst_set(skb, dst); 1208 1209 if (hop_limit == 0) { 1210 if (skb->protocol == htons(ETH_P_IP)) 1211 hop_limit = ip_hdr(skb)->ttl; 1212 else if (skb->protocol == htons(ETH_P_IPV6)) 1213 hop_limit = ipv6_hdr(skb)->hop_limit; 1214 else 1215 hop_limit = ip6_dst_hoplimit(dst); 1216 } 1217 1218 /* Calculate max headroom for all the headers and adjust 1219 * needed_headroom if necessary. 1220 */ 1221 max_headroom = LL_RESERVED_SPACE(dst->dev) + sizeof(struct ipv6hdr) 1222 + dst->header_len + t->hlen; 1223 if (max_headroom > dev->needed_headroom) 1224 dev->needed_headroom = max_headroom; 1225 1226 err = ip6_tnl_encap(skb, t, &proto, fl6); 1227 if (err) 1228 return err; 1229 1230 if (encap_limit >= 0) { 1231 init_tel_txopt(&opt, encap_limit); 1232 ipv6_push_frag_opts(skb, &opt.ops, &proto); 1233 } 1234 1235 skb_push(skb, sizeof(struct ipv6hdr)); 1236 skb_reset_network_header(skb); 1237 ipv6h = ipv6_hdr(skb); 1238 ip6_flow_hdr(ipv6h, dsfield, 1239 ip6_make_flowlabel(net, skb, fl6->flowlabel, true, fl6)); 1240 ipv6h->hop_limit = hop_limit; 1241 ipv6h->nexthdr = proto; 1242 ipv6h->saddr = fl6->saddr; 1243 ipv6h->daddr = fl6->daddr; 1244 ip6tunnel_xmit(NULL, skb, dev); 1245 return 0; 1246 tx_err_link_failure: 1247 stats->tx_carrier_errors++; 1248 dst_link_failure(skb); 1249 tx_err_dst_release: 1250 dst_release(dst); 1251 return err; 1252 } 1253 EXPORT_SYMBOL(ip6_tnl_xmit); 1254 1255 static inline int 1256 ip4ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev) 1257 { 1258 struct ip6_tnl *t = netdev_priv(dev); 1259 const struct iphdr *iph; 1260 int encap_limit = -1; 1261 struct flowi6 fl6; 1262 __u8 dsfield; 1263 __u32 mtu; 1264 u8 tproto; 1265 int err; 1266 1267 iph = ip_hdr(skb); 1268 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); 1269 1270 tproto = READ_ONCE(t->parms.proto); 1271 if (tproto != IPPROTO_IPIP && tproto != 0) 1272 return -1; 1273 1274 if (t->parms.collect_md) { 1275 struct ip_tunnel_info *tun_info; 1276 const struct ip_tunnel_key *key; 1277 1278 tun_info = skb_tunnel_info(skb); 1279 if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) || 1280 ip_tunnel_info_af(tun_info) != AF_INET6)) 1281 return -1; 1282 key = &tun_info->key; 1283 memset(&fl6, 0, sizeof(fl6)); 1284 fl6.flowi6_proto = IPPROTO_IPIP; 1285 fl6.saddr = key->u.ipv6.src; 1286 fl6.daddr = key->u.ipv6.dst; 1287 fl6.flowlabel = key->label; 1288 dsfield = key->tos; 1289 } else { 1290 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1291 encap_limit = t->parms.encap_limit; 1292 1293 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 1294 fl6.flowi6_proto = IPPROTO_IPIP; 1295 1296 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) 1297 dsfield = ipv4_get_dsfield(iph); 1298 else 1299 dsfield = ip6_tclass(t->parms.flowinfo); 1300 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK) 1301 fl6.flowi6_mark = skb->mark; 1302 else 1303 fl6.flowi6_mark = t->parms.fwmark; 1304 } 1305 1306 fl6.flowi6_uid = sock_net_uid(dev_net(dev), NULL); 1307 dsfield = INET_ECN_encapsulate(dsfield, ipv4_get_dsfield(iph)); 1308 1309 if (iptunnel_handle_offloads(skb, SKB_GSO_IPXIP6)) 1310 return -1; 1311 1312 skb_set_inner_ipproto(skb, IPPROTO_IPIP); 1313 1314 err = ip6_tnl_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu, 1315 IPPROTO_IPIP); 1316 if (err != 0) { 1317 /* XXX: send ICMP error even if DF is not set. */ 1318 if (err == -EMSGSIZE) 1319 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, 1320 htonl(mtu)); 1321 return -1; 1322 } 1323 1324 return 0; 1325 } 1326 1327 static inline int 1328 ip6ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev) 1329 { 1330 struct ip6_tnl *t = netdev_priv(dev); 1331 struct ipv6hdr *ipv6h; 1332 int encap_limit = -1; 1333 __u16 offset; 1334 struct flowi6 fl6; 1335 __u8 dsfield; 1336 __u32 mtu; 1337 u8 tproto; 1338 int err; 1339 1340 ipv6h = ipv6_hdr(skb); 1341 tproto = READ_ONCE(t->parms.proto); 1342 if ((tproto != IPPROTO_IPV6 && tproto != 0) || 1343 ip6_tnl_addr_conflict(t, ipv6h)) 1344 return -1; 1345 1346 if (t->parms.collect_md) { 1347 struct ip_tunnel_info *tun_info; 1348 const struct ip_tunnel_key *key; 1349 1350 tun_info = skb_tunnel_info(skb); 1351 if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) || 1352 ip_tunnel_info_af(tun_info) != AF_INET6)) 1353 return -1; 1354 key = &tun_info->key; 1355 memset(&fl6, 0, sizeof(fl6)); 1356 fl6.flowi6_proto = IPPROTO_IPV6; 1357 fl6.saddr = key->u.ipv6.src; 1358 fl6.daddr = key->u.ipv6.dst; 1359 fl6.flowlabel = key->label; 1360 dsfield = key->tos; 1361 } else { 1362 offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb)); 1363 /* ip6_tnl_parse_tlv_enc_lim() might have reallocated skb->head */ 1364 ipv6h = ipv6_hdr(skb); 1365 if (offset > 0) { 1366 struct ipv6_tlv_tnl_enc_lim *tel; 1367 1368 tel = (void *)&skb_network_header(skb)[offset]; 1369 if (tel->encap_limit == 0) { 1370 icmpv6_send(skb, ICMPV6_PARAMPROB, 1371 ICMPV6_HDR_FIELD, offset + 2); 1372 return -1; 1373 } 1374 encap_limit = tel->encap_limit - 1; 1375 } else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) { 1376 encap_limit = t->parms.encap_limit; 1377 } 1378 1379 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 1380 fl6.flowi6_proto = IPPROTO_IPV6; 1381 1382 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) 1383 dsfield = ipv6_get_dsfield(ipv6h); 1384 else 1385 dsfield = ip6_tclass(t->parms.flowinfo); 1386 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL) 1387 fl6.flowlabel |= ip6_flowlabel(ipv6h); 1388 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK) 1389 fl6.flowi6_mark = skb->mark; 1390 else 1391 fl6.flowi6_mark = t->parms.fwmark; 1392 } 1393 1394 fl6.flowi6_uid = sock_net_uid(dev_net(dev), NULL); 1395 dsfield = INET_ECN_encapsulate(dsfield, ipv6_get_dsfield(ipv6h)); 1396 1397 if (iptunnel_handle_offloads(skb, SKB_GSO_IPXIP6)) 1398 return -1; 1399 1400 skb_set_inner_ipproto(skb, IPPROTO_IPV6); 1401 1402 err = ip6_tnl_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu, 1403 IPPROTO_IPV6); 1404 if (err != 0) { 1405 if (err == -EMSGSIZE) 1406 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); 1407 return -1; 1408 } 1409 1410 return 0; 1411 } 1412 1413 static netdev_tx_t 1414 ip6_tnl_start_xmit(struct sk_buff *skb, struct net_device *dev) 1415 { 1416 struct ip6_tnl *t = netdev_priv(dev); 1417 struct net_device_stats *stats = &t->dev->stats; 1418 int ret; 1419 1420 if (!pskb_inet_may_pull(skb)) 1421 goto tx_err; 1422 1423 switch (skb->protocol) { 1424 case htons(ETH_P_IP): 1425 ret = ip4ip6_tnl_xmit(skb, dev); 1426 break; 1427 case htons(ETH_P_IPV6): 1428 ret = ip6ip6_tnl_xmit(skb, dev); 1429 break; 1430 default: 1431 goto tx_err; 1432 } 1433 1434 if (ret < 0) 1435 goto tx_err; 1436 1437 return NETDEV_TX_OK; 1438 1439 tx_err: 1440 stats->tx_errors++; 1441 stats->tx_dropped++; 1442 kfree_skb(skb); 1443 return NETDEV_TX_OK; 1444 } 1445 1446 static void ip6_tnl_link_config(struct ip6_tnl *t) 1447 { 1448 struct net_device *dev = t->dev; 1449 struct net_device *tdev = NULL; 1450 struct __ip6_tnl_parm *p = &t->parms; 1451 struct flowi6 *fl6 = &t->fl.u.ip6; 1452 unsigned int mtu; 1453 int t_hlen; 1454 1455 memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr)); 1456 memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr)); 1457 1458 /* Set up flowi template */ 1459 fl6->saddr = p->laddr; 1460 fl6->daddr = p->raddr; 1461 fl6->flowi6_oif = p->link; 1462 fl6->flowlabel = 0; 1463 1464 if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS)) 1465 fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo; 1466 if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL)) 1467 fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo; 1468 1469 p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET); 1470 p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr); 1471 1472 if (p->flags&IP6_TNL_F_CAP_XMIT && p->flags&IP6_TNL_F_CAP_RCV) 1473 dev->flags |= IFF_POINTOPOINT; 1474 else 1475 dev->flags &= ~IFF_POINTOPOINT; 1476 1477 t->tun_hlen = 0; 1478 t->hlen = t->encap_hlen + t->tun_hlen; 1479 t_hlen = t->hlen + sizeof(struct ipv6hdr); 1480 1481 if (p->flags & IP6_TNL_F_CAP_XMIT) { 1482 int strict = (ipv6_addr_type(&p->raddr) & 1483 (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL)); 1484 1485 struct rt6_info *rt = rt6_lookup(t->net, 1486 &p->raddr, &p->laddr, 1487 p->link, NULL, strict); 1488 if (rt) { 1489 tdev = rt->dst.dev; 1490 ip6_rt_put(rt); 1491 } 1492 1493 if (!tdev && p->link) 1494 tdev = __dev_get_by_index(t->net, p->link); 1495 1496 if (tdev) { 1497 dev->hard_header_len = tdev->hard_header_len + t_hlen; 1498 mtu = min_t(unsigned int, tdev->mtu, IP6_MAX_MTU); 1499 1500 dev->mtu = mtu - t_hlen; 1501 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1502 dev->mtu -= 8; 1503 1504 if (dev->mtu < IPV6_MIN_MTU) 1505 dev->mtu = IPV6_MIN_MTU; 1506 } 1507 } 1508 } 1509 1510 /** 1511 * ip6_tnl_change - update the tunnel parameters 1512 * @t: tunnel to be changed 1513 * @p: tunnel configuration parameters 1514 * 1515 * Description: 1516 * ip6_tnl_change() updates the tunnel parameters 1517 **/ 1518 1519 static int 1520 ip6_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p) 1521 { 1522 t->parms.laddr = p->laddr; 1523 t->parms.raddr = p->raddr; 1524 t->parms.flags = p->flags; 1525 t->parms.hop_limit = p->hop_limit; 1526 t->parms.encap_limit = p->encap_limit; 1527 t->parms.flowinfo = p->flowinfo; 1528 t->parms.link = p->link; 1529 t->parms.proto = p->proto; 1530 t->parms.fwmark = p->fwmark; 1531 dst_cache_reset(&t->dst_cache); 1532 ip6_tnl_link_config(t); 1533 return 0; 1534 } 1535 1536 static int ip6_tnl_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p) 1537 { 1538 struct net *net = t->net; 1539 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1540 int err; 1541 1542 ip6_tnl_unlink(ip6n, t); 1543 synchronize_net(); 1544 err = ip6_tnl_change(t, p); 1545 ip6_tnl_link(ip6n, t); 1546 netdev_state_change(t->dev); 1547 return err; 1548 } 1549 1550 static int ip6_tnl0_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p) 1551 { 1552 /* for default tnl0 device allow to change only the proto */ 1553 t->parms.proto = p->proto; 1554 netdev_state_change(t->dev); 1555 return 0; 1556 } 1557 1558 static void 1559 ip6_tnl_parm_from_user(struct __ip6_tnl_parm *p, const struct ip6_tnl_parm *u) 1560 { 1561 p->laddr = u->laddr; 1562 p->raddr = u->raddr; 1563 p->flags = u->flags; 1564 p->hop_limit = u->hop_limit; 1565 p->encap_limit = u->encap_limit; 1566 p->flowinfo = u->flowinfo; 1567 p->link = u->link; 1568 p->proto = u->proto; 1569 memcpy(p->name, u->name, sizeof(u->name)); 1570 } 1571 1572 static void 1573 ip6_tnl_parm_to_user(struct ip6_tnl_parm *u, const struct __ip6_tnl_parm *p) 1574 { 1575 u->laddr = p->laddr; 1576 u->raddr = p->raddr; 1577 u->flags = p->flags; 1578 u->hop_limit = p->hop_limit; 1579 u->encap_limit = p->encap_limit; 1580 u->flowinfo = p->flowinfo; 1581 u->link = p->link; 1582 u->proto = p->proto; 1583 memcpy(u->name, p->name, sizeof(u->name)); 1584 } 1585 1586 /** 1587 * ip6_tnl_ioctl - configure ipv6 tunnels from userspace 1588 * @dev: virtual device associated with tunnel 1589 * @ifr: parameters passed from userspace 1590 * @cmd: command to be performed 1591 * 1592 * Description: 1593 * ip6_tnl_ioctl() is used for managing IPv6 tunnels 1594 * from userspace. 1595 * 1596 * The possible commands are the following: 1597 * %SIOCGETTUNNEL: get tunnel parameters for device 1598 * %SIOCADDTUNNEL: add tunnel matching given tunnel parameters 1599 * %SIOCCHGTUNNEL: change tunnel parameters to those given 1600 * %SIOCDELTUNNEL: delete tunnel 1601 * 1602 * The fallback device "ip6tnl0", created during module 1603 * initialization, can be used for creating other tunnel devices. 1604 * 1605 * Return: 1606 * 0 on success, 1607 * %-EFAULT if unable to copy data to or from userspace, 1608 * %-EPERM if current process hasn't %CAP_NET_ADMIN set 1609 * %-EINVAL if passed tunnel parameters are invalid, 1610 * %-EEXIST if changing a tunnel's parameters would cause a conflict 1611 * %-ENODEV if attempting to change or delete a nonexisting device 1612 **/ 1613 1614 static int 1615 ip6_tnl_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd) 1616 { 1617 int err = 0; 1618 struct ip6_tnl_parm p; 1619 struct __ip6_tnl_parm p1; 1620 struct ip6_tnl *t = netdev_priv(dev); 1621 struct net *net = t->net; 1622 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1623 1624 memset(&p1, 0, sizeof(p1)); 1625 1626 switch (cmd) { 1627 case SIOCGETTUNNEL: 1628 if (dev == ip6n->fb_tnl_dev) { 1629 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) { 1630 err = -EFAULT; 1631 break; 1632 } 1633 ip6_tnl_parm_from_user(&p1, &p); 1634 t = ip6_tnl_locate(net, &p1, 0); 1635 if (IS_ERR(t)) 1636 t = netdev_priv(dev); 1637 } else { 1638 memset(&p, 0, sizeof(p)); 1639 } 1640 ip6_tnl_parm_to_user(&p, &t->parms); 1641 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) { 1642 err = -EFAULT; 1643 } 1644 break; 1645 case SIOCADDTUNNEL: 1646 case SIOCCHGTUNNEL: 1647 err = -EPERM; 1648 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 1649 break; 1650 err = -EFAULT; 1651 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 1652 break; 1653 err = -EINVAL; 1654 if (p.proto != IPPROTO_IPV6 && p.proto != IPPROTO_IPIP && 1655 p.proto != 0) 1656 break; 1657 ip6_tnl_parm_from_user(&p1, &p); 1658 t = ip6_tnl_locate(net, &p1, cmd == SIOCADDTUNNEL); 1659 if (cmd == SIOCCHGTUNNEL) { 1660 if (!IS_ERR(t)) { 1661 if (t->dev != dev) { 1662 err = -EEXIST; 1663 break; 1664 } 1665 } else 1666 t = netdev_priv(dev); 1667 if (dev == ip6n->fb_tnl_dev) 1668 err = ip6_tnl0_update(t, &p1); 1669 else 1670 err = ip6_tnl_update(t, &p1); 1671 } 1672 if (!IS_ERR(t)) { 1673 err = 0; 1674 ip6_tnl_parm_to_user(&p, &t->parms); 1675 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) 1676 err = -EFAULT; 1677 1678 } else { 1679 err = PTR_ERR(t); 1680 } 1681 break; 1682 case SIOCDELTUNNEL: 1683 err = -EPERM; 1684 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 1685 break; 1686 1687 if (dev == ip6n->fb_tnl_dev) { 1688 err = -EFAULT; 1689 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 1690 break; 1691 err = -ENOENT; 1692 ip6_tnl_parm_from_user(&p1, &p); 1693 t = ip6_tnl_locate(net, &p1, 0); 1694 if (IS_ERR(t)) 1695 break; 1696 err = -EPERM; 1697 if (t->dev == ip6n->fb_tnl_dev) 1698 break; 1699 dev = t->dev; 1700 } 1701 err = 0; 1702 unregister_netdevice(dev); 1703 break; 1704 default: 1705 err = -EINVAL; 1706 } 1707 return err; 1708 } 1709 1710 /** 1711 * ip6_tnl_change_mtu - change mtu manually for tunnel device 1712 * @dev: virtual device associated with tunnel 1713 * @new_mtu: the new mtu 1714 * 1715 * Return: 1716 * 0 on success, 1717 * %-EINVAL if mtu too small 1718 **/ 1719 1720 int ip6_tnl_change_mtu(struct net_device *dev, int new_mtu) 1721 { 1722 struct ip6_tnl *tnl = netdev_priv(dev); 1723 1724 if (tnl->parms.proto == IPPROTO_IPV6) { 1725 if (new_mtu < IPV6_MIN_MTU) 1726 return -EINVAL; 1727 } else { 1728 if (new_mtu < ETH_MIN_MTU) 1729 return -EINVAL; 1730 } 1731 if (tnl->parms.proto == IPPROTO_IPV6 || tnl->parms.proto == 0) { 1732 if (new_mtu > IP6_MAX_MTU - dev->hard_header_len) 1733 return -EINVAL; 1734 } else { 1735 if (new_mtu > IP_MAX_MTU - dev->hard_header_len) 1736 return -EINVAL; 1737 } 1738 dev->mtu = new_mtu; 1739 return 0; 1740 } 1741 EXPORT_SYMBOL(ip6_tnl_change_mtu); 1742 1743 int ip6_tnl_get_iflink(const struct net_device *dev) 1744 { 1745 struct ip6_tnl *t = netdev_priv(dev); 1746 1747 return t->parms.link; 1748 } 1749 EXPORT_SYMBOL(ip6_tnl_get_iflink); 1750 1751 int ip6_tnl_encap_add_ops(const struct ip6_tnl_encap_ops *ops, 1752 unsigned int num) 1753 { 1754 if (num >= MAX_IPTUN_ENCAP_OPS) 1755 return -ERANGE; 1756 1757 return !cmpxchg((const struct ip6_tnl_encap_ops **) 1758 &ip6tun_encaps[num], 1759 NULL, ops) ? 0 : -1; 1760 } 1761 EXPORT_SYMBOL(ip6_tnl_encap_add_ops); 1762 1763 int ip6_tnl_encap_del_ops(const struct ip6_tnl_encap_ops *ops, 1764 unsigned int num) 1765 { 1766 int ret; 1767 1768 if (num >= MAX_IPTUN_ENCAP_OPS) 1769 return -ERANGE; 1770 1771 ret = (cmpxchg((const struct ip6_tnl_encap_ops **) 1772 &ip6tun_encaps[num], 1773 ops, NULL) == ops) ? 0 : -1; 1774 1775 synchronize_net(); 1776 1777 return ret; 1778 } 1779 EXPORT_SYMBOL(ip6_tnl_encap_del_ops); 1780 1781 int ip6_tnl_encap_setup(struct ip6_tnl *t, 1782 struct ip_tunnel_encap *ipencap) 1783 { 1784 int hlen; 1785 1786 memset(&t->encap, 0, sizeof(t->encap)); 1787 1788 hlen = ip6_encap_hlen(ipencap); 1789 if (hlen < 0) 1790 return hlen; 1791 1792 t->encap.type = ipencap->type; 1793 t->encap.sport = ipencap->sport; 1794 t->encap.dport = ipencap->dport; 1795 t->encap.flags = ipencap->flags; 1796 1797 t->encap_hlen = hlen; 1798 t->hlen = t->encap_hlen + t->tun_hlen; 1799 1800 return 0; 1801 } 1802 EXPORT_SYMBOL_GPL(ip6_tnl_encap_setup); 1803 1804 static const struct net_device_ops ip6_tnl_netdev_ops = { 1805 .ndo_init = ip6_tnl_dev_init, 1806 .ndo_uninit = ip6_tnl_dev_uninit, 1807 .ndo_start_xmit = ip6_tnl_start_xmit, 1808 .ndo_do_ioctl = ip6_tnl_ioctl, 1809 .ndo_change_mtu = ip6_tnl_change_mtu, 1810 .ndo_get_stats = ip6_get_stats, 1811 .ndo_get_iflink = ip6_tnl_get_iflink, 1812 }; 1813 1814 #define IPXIPX_FEATURES (NETIF_F_SG | \ 1815 NETIF_F_FRAGLIST | \ 1816 NETIF_F_HIGHDMA | \ 1817 NETIF_F_GSO_SOFTWARE | \ 1818 NETIF_F_HW_CSUM) 1819 1820 /** 1821 * ip6_tnl_dev_setup - setup virtual tunnel device 1822 * @dev: virtual device associated with tunnel 1823 * 1824 * Description: 1825 * Initialize function pointers and device parameters 1826 **/ 1827 1828 static void ip6_tnl_dev_setup(struct net_device *dev) 1829 { 1830 dev->netdev_ops = &ip6_tnl_netdev_ops; 1831 dev->needs_free_netdev = true; 1832 dev->priv_destructor = ip6_dev_free; 1833 1834 dev->type = ARPHRD_TUNNEL6; 1835 dev->flags |= IFF_NOARP; 1836 dev->addr_len = sizeof(struct in6_addr); 1837 dev->features |= NETIF_F_LLTX; 1838 netif_keep_dst(dev); 1839 1840 dev->features |= IPXIPX_FEATURES; 1841 dev->hw_features |= IPXIPX_FEATURES; 1842 1843 /* This perm addr will be used as interface identifier by IPv6 */ 1844 dev->addr_assign_type = NET_ADDR_RANDOM; 1845 eth_random_addr(dev->perm_addr); 1846 } 1847 1848 1849 /** 1850 * ip6_tnl_dev_init_gen - general initializer for all tunnel devices 1851 * @dev: virtual device associated with tunnel 1852 **/ 1853 1854 static inline int 1855 ip6_tnl_dev_init_gen(struct net_device *dev) 1856 { 1857 struct ip6_tnl *t = netdev_priv(dev); 1858 int ret; 1859 int t_hlen; 1860 1861 t->dev = dev; 1862 t->net = dev_net(dev); 1863 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats); 1864 if (!dev->tstats) 1865 return -ENOMEM; 1866 1867 ret = dst_cache_init(&t->dst_cache, GFP_KERNEL); 1868 if (ret) 1869 goto free_stats; 1870 1871 ret = gro_cells_init(&t->gro_cells, dev); 1872 if (ret) 1873 goto destroy_dst; 1874 1875 t->tun_hlen = 0; 1876 t->hlen = t->encap_hlen + t->tun_hlen; 1877 t_hlen = t->hlen + sizeof(struct ipv6hdr); 1878 1879 dev->type = ARPHRD_TUNNEL6; 1880 dev->hard_header_len = LL_MAX_HEADER + t_hlen; 1881 dev->mtu = ETH_DATA_LEN - t_hlen; 1882 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1883 dev->mtu -= 8; 1884 dev->min_mtu = ETH_MIN_MTU; 1885 dev->max_mtu = IP6_MAX_MTU - dev->hard_header_len; 1886 1887 return 0; 1888 1889 destroy_dst: 1890 dst_cache_destroy(&t->dst_cache); 1891 free_stats: 1892 free_percpu(dev->tstats); 1893 dev->tstats = NULL; 1894 1895 return ret; 1896 } 1897 1898 /** 1899 * ip6_tnl_dev_init - initializer for all non fallback tunnel devices 1900 * @dev: virtual device associated with tunnel 1901 **/ 1902 1903 static int ip6_tnl_dev_init(struct net_device *dev) 1904 { 1905 struct ip6_tnl *t = netdev_priv(dev); 1906 int err = ip6_tnl_dev_init_gen(dev); 1907 1908 if (err) 1909 return err; 1910 ip6_tnl_link_config(t); 1911 if (t->parms.collect_md) 1912 netif_keep_dst(dev); 1913 return 0; 1914 } 1915 1916 /** 1917 * ip6_fb_tnl_dev_init - initializer for fallback tunnel device 1918 * @dev: fallback device 1919 * 1920 * Return: 0 1921 **/ 1922 1923 static int __net_init ip6_fb_tnl_dev_init(struct net_device *dev) 1924 { 1925 struct ip6_tnl *t = netdev_priv(dev); 1926 struct net *net = dev_net(dev); 1927 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1928 1929 t->parms.proto = IPPROTO_IPV6; 1930 dev_hold(dev); 1931 1932 rcu_assign_pointer(ip6n->tnls_wc[0], t); 1933 return 0; 1934 } 1935 1936 static int ip6_tnl_validate(struct nlattr *tb[], struct nlattr *data[], 1937 struct netlink_ext_ack *extack) 1938 { 1939 u8 proto; 1940 1941 if (!data || !data[IFLA_IPTUN_PROTO]) 1942 return 0; 1943 1944 proto = nla_get_u8(data[IFLA_IPTUN_PROTO]); 1945 if (proto != IPPROTO_IPV6 && 1946 proto != IPPROTO_IPIP && 1947 proto != 0) 1948 return -EINVAL; 1949 1950 return 0; 1951 } 1952 1953 static void ip6_tnl_netlink_parms(struct nlattr *data[], 1954 struct __ip6_tnl_parm *parms) 1955 { 1956 memset(parms, 0, sizeof(*parms)); 1957 1958 if (!data) 1959 return; 1960 1961 if (data[IFLA_IPTUN_LINK]) 1962 parms->link = nla_get_u32(data[IFLA_IPTUN_LINK]); 1963 1964 if (data[IFLA_IPTUN_LOCAL]) 1965 parms->laddr = nla_get_in6_addr(data[IFLA_IPTUN_LOCAL]); 1966 1967 if (data[IFLA_IPTUN_REMOTE]) 1968 parms->raddr = nla_get_in6_addr(data[IFLA_IPTUN_REMOTE]); 1969 1970 if (data[IFLA_IPTUN_TTL]) 1971 parms->hop_limit = nla_get_u8(data[IFLA_IPTUN_TTL]); 1972 1973 if (data[IFLA_IPTUN_ENCAP_LIMIT]) 1974 parms->encap_limit = nla_get_u8(data[IFLA_IPTUN_ENCAP_LIMIT]); 1975 1976 if (data[IFLA_IPTUN_FLOWINFO]) 1977 parms->flowinfo = nla_get_be32(data[IFLA_IPTUN_FLOWINFO]); 1978 1979 if (data[IFLA_IPTUN_FLAGS]) 1980 parms->flags = nla_get_u32(data[IFLA_IPTUN_FLAGS]); 1981 1982 if (data[IFLA_IPTUN_PROTO]) 1983 parms->proto = nla_get_u8(data[IFLA_IPTUN_PROTO]); 1984 1985 if (data[IFLA_IPTUN_COLLECT_METADATA]) 1986 parms->collect_md = true; 1987 1988 if (data[IFLA_IPTUN_FWMARK]) 1989 parms->fwmark = nla_get_u32(data[IFLA_IPTUN_FWMARK]); 1990 } 1991 1992 static bool ip6_tnl_netlink_encap_parms(struct nlattr *data[], 1993 struct ip_tunnel_encap *ipencap) 1994 { 1995 bool ret = false; 1996 1997 memset(ipencap, 0, sizeof(*ipencap)); 1998 1999 if (!data) 2000 return ret; 2001 2002 if (data[IFLA_IPTUN_ENCAP_TYPE]) { 2003 ret = true; 2004 ipencap->type = nla_get_u16(data[IFLA_IPTUN_ENCAP_TYPE]); 2005 } 2006 2007 if (data[IFLA_IPTUN_ENCAP_FLAGS]) { 2008 ret = true; 2009 ipencap->flags = nla_get_u16(data[IFLA_IPTUN_ENCAP_FLAGS]); 2010 } 2011 2012 if (data[IFLA_IPTUN_ENCAP_SPORT]) { 2013 ret = true; 2014 ipencap->sport = nla_get_be16(data[IFLA_IPTUN_ENCAP_SPORT]); 2015 } 2016 2017 if (data[IFLA_IPTUN_ENCAP_DPORT]) { 2018 ret = true; 2019 ipencap->dport = nla_get_be16(data[IFLA_IPTUN_ENCAP_DPORT]); 2020 } 2021 2022 return ret; 2023 } 2024 2025 static int ip6_tnl_newlink(struct net *src_net, struct net_device *dev, 2026 struct nlattr *tb[], struct nlattr *data[], 2027 struct netlink_ext_ack *extack) 2028 { 2029 struct net *net = dev_net(dev); 2030 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 2031 struct ip_tunnel_encap ipencap; 2032 struct ip6_tnl *nt, *t; 2033 int err; 2034 2035 nt = netdev_priv(dev); 2036 2037 if (ip6_tnl_netlink_encap_parms(data, &ipencap)) { 2038 err = ip6_tnl_encap_setup(nt, &ipencap); 2039 if (err < 0) 2040 return err; 2041 } 2042 2043 ip6_tnl_netlink_parms(data, &nt->parms); 2044 2045 if (nt->parms.collect_md) { 2046 if (rtnl_dereference(ip6n->collect_md_tun)) 2047 return -EEXIST; 2048 } else { 2049 t = ip6_tnl_locate(net, &nt->parms, 0); 2050 if (!IS_ERR(t)) 2051 return -EEXIST; 2052 } 2053 2054 err = ip6_tnl_create2(dev); 2055 if (!err && tb[IFLA_MTU]) 2056 ip6_tnl_change_mtu(dev, nla_get_u32(tb[IFLA_MTU])); 2057 2058 return err; 2059 } 2060 2061 static int ip6_tnl_changelink(struct net_device *dev, struct nlattr *tb[], 2062 struct nlattr *data[], 2063 struct netlink_ext_ack *extack) 2064 { 2065 struct ip6_tnl *t = netdev_priv(dev); 2066 struct __ip6_tnl_parm p; 2067 struct net *net = t->net; 2068 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 2069 struct ip_tunnel_encap ipencap; 2070 2071 if (dev == ip6n->fb_tnl_dev) 2072 return -EINVAL; 2073 2074 if (ip6_tnl_netlink_encap_parms(data, &ipencap)) { 2075 int err = ip6_tnl_encap_setup(t, &ipencap); 2076 2077 if (err < 0) 2078 return err; 2079 } 2080 ip6_tnl_netlink_parms(data, &p); 2081 if (p.collect_md) 2082 return -EINVAL; 2083 2084 t = ip6_tnl_locate(net, &p, 0); 2085 if (!IS_ERR(t)) { 2086 if (t->dev != dev) 2087 return -EEXIST; 2088 } else 2089 t = netdev_priv(dev); 2090 2091 return ip6_tnl_update(t, &p); 2092 } 2093 2094 static void ip6_tnl_dellink(struct net_device *dev, struct list_head *head) 2095 { 2096 struct net *net = dev_net(dev); 2097 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 2098 2099 if (dev != ip6n->fb_tnl_dev) 2100 unregister_netdevice_queue(dev, head); 2101 } 2102 2103 static size_t ip6_tnl_get_size(const struct net_device *dev) 2104 { 2105 return 2106 /* IFLA_IPTUN_LINK */ 2107 nla_total_size(4) + 2108 /* IFLA_IPTUN_LOCAL */ 2109 nla_total_size(sizeof(struct in6_addr)) + 2110 /* IFLA_IPTUN_REMOTE */ 2111 nla_total_size(sizeof(struct in6_addr)) + 2112 /* IFLA_IPTUN_TTL */ 2113 nla_total_size(1) + 2114 /* IFLA_IPTUN_ENCAP_LIMIT */ 2115 nla_total_size(1) + 2116 /* IFLA_IPTUN_FLOWINFO */ 2117 nla_total_size(4) + 2118 /* IFLA_IPTUN_FLAGS */ 2119 nla_total_size(4) + 2120 /* IFLA_IPTUN_PROTO */ 2121 nla_total_size(1) + 2122 /* IFLA_IPTUN_ENCAP_TYPE */ 2123 nla_total_size(2) + 2124 /* IFLA_IPTUN_ENCAP_FLAGS */ 2125 nla_total_size(2) + 2126 /* IFLA_IPTUN_ENCAP_SPORT */ 2127 nla_total_size(2) + 2128 /* IFLA_IPTUN_ENCAP_DPORT */ 2129 nla_total_size(2) + 2130 /* IFLA_IPTUN_COLLECT_METADATA */ 2131 nla_total_size(0) + 2132 /* IFLA_IPTUN_FWMARK */ 2133 nla_total_size(4) + 2134 0; 2135 } 2136 2137 static int ip6_tnl_fill_info(struct sk_buff *skb, const struct net_device *dev) 2138 { 2139 struct ip6_tnl *tunnel = netdev_priv(dev); 2140 struct __ip6_tnl_parm *parm = &tunnel->parms; 2141 2142 if (nla_put_u32(skb, IFLA_IPTUN_LINK, parm->link) || 2143 nla_put_in6_addr(skb, IFLA_IPTUN_LOCAL, &parm->laddr) || 2144 nla_put_in6_addr(skb, IFLA_IPTUN_REMOTE, &parm->raddr) || 2145 nla_put_u8(skb, IFLA_IPTUN_TTL, parm->hop_limit) || 2146 nla_put_u8(skb, IFLA_IPTUN_ENCAP_LIMIT, parm->encap_limit) || 2147 nla_put_be32(skb, IFLA_IPTUN_FLOWINFO, parm->flowinfo) || 2148 nla_put_u32(skb, IFLA_IPTUN_FLAGS, parm->flags) || 2149 nla_put_u8(skb, IFLA_IPTUN_PROTO, parm->proto) || 2150 nla_put_u32(skb, IFLA_IPTUN_FWMARK, parm->fwmark)) 2151 goto nla_put_failure; 2152 2153 if (nla_put_u16(skb, IFLA_IPTUN_ENCAP_TYPE, tunnel->encap.type) || 2154 nla_put_be16(skb, IFLA_IPTUN_ENCAP_SPORT, tunnel->encap.sport) || 2155 nla_put_be16(skb, IFLA_IPTUN_ENCAP_DPORT, tunnel->encap.dport) || 2156 nla_put_u16(skb, IFLA_IPTUN_ENCAP_FLAGS, tunnel->encap.flags)) 2157 goto nla_put_failure; 2158 2159 if (parm->collect_md) 2160 if (nla_put_flag(skb, IFLA_IPTUN_COLLECT_METADATA)) 2161 goto nla_put_failure; 2162 2163 return 0; 2164 2165 nla_put_failure: 2166 return -EMSGSIZE; 2167 } 2168 2169 struct net *ip6_tnl_get_link_net(const struct net_device *dev) 2170 { 2171 struct ip6_tnl *tunnel = netdev_priv(dev); 2172 2173 return tunnel->net; 2174 } 2175 EXPORT_SYMBOL(ip6_tnl_get_link_net); 2176 2177 static const struct nla_policy ip6_tnl_policy[IFLA_IPTUN_MAX + 1] = { 2178 [IFLA_IPTUN_LINK] = { .type = NLA_U32 }, 2179 [IFLA_IPTUN_LOCAL] = { .len = sizeof(struct in6_addr) }, 2180 [IFLA_IPTUN_REMOTE] = { .len = sizeof(struct in6_addr) }, 2181 [IFLA_IPTUN_TTL] = { .type = NLA_U8 }, 2182 [IFLA_IPTUN_ENCAP_LIMIT] = { .type = NLA_U8 }, 2183 [IFLA_IPTUN_FLOWINFO] = { .type = NLA_U32 }, 2184 [IFLA_IPTUN_FLAGS] = { .type = NLA_U32 }, 2185 [IFLA_IPTUN_PROTO] = { .type = NLA_U8 }, 2186 [IFLA_IPTUN_ENCAP_TYPE] = { .type = NLA_U16 }, 2187 [IFLA_IPTUN_ENCAP_FLAGS] = { .type = NLA_U16 }, 2188 [IFLA_IPTUN_ENCAP_SPORT] = { .type = NLA_U16 }, 2189 [IFLA_IPTUN_ENCAP_DPORT] = { .type = NLA_U16 }, 2190 [IFLA_IPTUN_COLLECT_METADATA] = { .type = NLA_FLAG }, 2191 [IFLA_IPTUN_FWMARK] = { .type = NLA_U32 }, 2192 }; 2193 2194 static struct rtnl_link_ops ip6_link_ops __read_mostly = { 2195 .kind = "ip6tnl", 2196 .maxtype = IFLA_IPTUN_MAX, 2197 .policy = ip6_tnl_policy, 2198 .priv_size = sizeof(struct ip6_tnl), 2199 .setup = ip6_tnl_dev_setup, 2200 .validate = ip6_tnl_validate, 2201 .newlink = ip6_tnl_newlink, 2202 .changelink = ip6_tnl_changelink, 2203 .dellink = ip6_tnl_dellink, 2204 .get_size = ip6_tnl_get_size, 2205 .fill_info = ip6_tnl_fill_info, 2206 .get_link_net = ip6_tnl_get_link_net, 2207 }; 2208 2209 static struct xfrm6_tunnel ip4ip6_handler __read_mostly = { 2210 .handler = ip4ip6_rcv, 2211 .err_handler = ip4ip6_err, 2212 .priority = 1, 2213 }; 2214 2215 static struct xfrm6_tunnel ip6ip6_handler __read_mostly = { 2216 .handler = ip6ip6_rcv, 2217 .err_handler = ip6ip6_err, 2218 .priority = 1, 2219 }; 2220 2221 static void __net_exit ip6_tnl_destroy_tunnels(struct net *net, struct list_head *list) 2222 { 2223 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 2224 struct net_device *dev, *aux; 2225 int h; 2226 struct ip6_tnl *t; 2227 2228 for_each_netdev_safe(net, dev, aux) 2229 if (dev->rtnl_link_ops == &ip6_link_ops) 2230 unregister_netdevice_queue(dev, list); 2231 2232 for (h = 0; h < IP6_TUNNEL_HASH_SIZE; h++) { 2233 t = rtnl_dereference(ip6n->tnls_r_l[h]); 2234 while (t) { 2235 /* If dev is in the same netns, it has already 2236 * been added to the list by the previous loop. 2237 */ 2238 if (!net_eq(dev_net(t->dev), net)) 2239 unregister_netdevice_queue(t->dev, list); 2240 t = rtnl_dereference(t->next); 2241 } 2242 } 2243 } 2244 2245 static int __net_init ip6_tnl_init_net(struct net *net) 2246 { 2247 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 2248 struct ip6_tnl *t = NULL; 2249 int err; 2250 2251 ip6n->tnls[0] = ip6n->tnls_wc; 2252 ip6n->tnls[1] = ip6n->tnls_r_l; 2253 2254 if (!net_has_fallback_tunnels(net)) 2255 return 0; 2256 err = -ENOMEM; 2257 ip6n->fb_tnl_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6tnl0", 2258 NET_NAME_UNKNOWN, ip6_tnl_dev_setup); 2259 2260 if (!ip6n->fb_tnl_dev) 2261 goto err_alloc_dev; 2262 dev_net_set(ip6n->fb_tnl_dev, net); 2263 ip6n->fb_tnl_dev->rtnl_link_ops = &ip6_link_ops; 2264 /* FB netdevice is special: we have one, and only one per netns. 2265 * Allowing to move it to another netns is clearly unsafe. 2266 */ 2267 ip6n->fb_tnl_dev->features |= NETIF_F_NETNS_LOCAL; 2268 2269 err = ip6_fb_tnl_dev_init(ip6n->fb_tnl_dev); 2270 if (err < 0) 2271 goto err_register; 2272 2273 err = register_netdev(ip6n->fb_tnl_dev); 2274 if (err < 0) 2275 goto err_register; 2276 2277 t = netdev_priv(ip6n->fb_tnl_dev); 2278 2279 strcpy(t->parms.name, ip6n->fb_tnl_dev->name); 2280 return 0; 2281 2282 err_register: 2283 free_netdev(ip6n->fb_tnl_dev); 2284 err_alloc_dev: 2285 return err; 2286 } 2287 2288 static void __net_exit ip6_tnl_exit_batch_net(struct list_head *net_list) 2289 { 2290 struct net *net; 2291 LIST_HEAD(list); 2292 2293 rtnl_lock(); 2294 list_for_each_entry(net, net_list, exit_list) 2295 ip6_tnl_destroy_tunnels(net, &list); 2296 unregister_netdevice_many(&list); 2297 rtnl_unlock(); 2298 } 2299 2300 static struct pernet_operations ip6_tnl_net_ops = { 2301 .init = ip6_tnl_init_net, 2302 .exit_batch = ip6_tnl_exit_batch_net, 2303 .id = &ip6_tnl_net_id, 2304 .size = sizeof(struct ip6_tnl_net), 2305 }; 2306 2307 /** 2308 * ip6_tunnel_init - register protocol and reserve needed resources 2309 * 2310 * Return: 0 on success 2311 **/ 2312 2313 static int __init ip6_tunnel_init(void) 2314 { 2315 int err; 2316 2317 if (!ipv6_mod_enabled()) 2318 return -EOPNOTSUPP; 2319 2320 err = register_pernet_device(&ip6_tnl_net_ops); 2321 if (err < 0) 2322 goto out_pernet; 2323 2324 err = xfrm6_tunnel_register(&ip4ip6_handler, AF_INET); 2325 if (err < 0) { 2326 pr_err("%s: can't register ip4ip6\n", __func__); 2327 goto out_ip4ip6; 2328 } 2329 2330 err = xfrm6_tunnel_register(&ip6ip6_handler, AF_INET6); 2331 if (err < 0) { 2332 pr_err("%s: can't register ip6ip6\n", __func__); 2333 goto out_ip6ip6; 2334 } 2335 err = rtnl_link_register(&ip6_link_ops); 2336 if (err < 0) 2337 goto rtnl_link_failed; 2338 2339 return 0; 2340 2341 rtnl_link_failed: 2342 xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6); 2343 out_ip6ip6: 2344 xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET); 2345 out_ip4ip6: 2346 unregister_pernet_device(&ip6_tnl_net_ops); 2347 out_pernet: 2348 return err; 2349 } 2350 2351 /** 2352 * ip6_tunnel_cleanup - free resources and unregister protocol 2353 **/ 2354 2355 static void __exit ip6_tunnel_cleanup(void) 2356 { 2357 rtnl_link_unregister(&ip6_link_ops); 2358 if (xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET)) 2359 pr_info("%s: can't deregister ip4ip6\n", __func__); 2360 2361 if (xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6)) 2362 pr_info("%s: can't deregister ip6ip6\n", __func__); 2363 2364 unregister_pernet_device(&ip6_tnl_net_ops); 2365 } 2366 2367 module_init(ip6_tunnel_init); 2368 module_exit(ip6_tunnel_cleanup); 2369