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 inline int ip6_tnl_mpls_supported(void) 93 { 94 return IS_ENABLED(CONFIG_MPLS); 95 } 96 97 #define for_each_ip6_tunnel_rcu(start) \ 98 for (t = rcu_dereference(start); t; t = rcu_dereference(t->next)) 99 100 /** 101 * ip6_tnl_lookup - fetch tunnel matching the end-point addresses 102 * @net: network namespace 103 * @link: ifindex of underlying interface 104 * @remote: the address of the tunnel exit-point 105 * @local: the address of the tunnel entry-point 106 * 107 * Return: 108 * tunnel matching given end-points if found, 109 * else fallback tunnel if its device is up, 110 * else %NULL 111 **/ 112 113 static struct ip6_tnl * 114 ip6_tnl_lookup(struct net *net, int link, 115 const struct in6_addr *remote, const struct in6_addr *local) 116 { 117 unsigned int hash = HASH(remote, local); 118 struct ip6_tnl *t, *cand = NULL; 119 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 120 struct in6_addr any; 121 122 for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) { 123 if (!ipv6_addr_equal(local, &t->parms.laddr) || 124 !ipv6_addr_equal(remote, &t->parms.raddr) || 125 !(t->dev->flags & IFF_UP)) 126 continue; 127 128 if (link == t->parms.link) 129 return t; 130 else 131 cand = t; 132 } 133 134 memset(&any, 0, sizeof(any)); 135 hash = HASH(&any, local); 136 for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) { 137 if (!ipv6_addr_equal(local, &t->parms.laddr) || 138 !ipv6_addr_any(&t->parms.raddr) || 139 !(t->dev->flags & IFF_UP)) 140 continue; 141 142 if (link == t->parms.link) 143 return t; 144 else if (!cand) 145 cand = t; 146 } 147 148 hash = HASH(remote, &any); 149 for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) { 150 if (!ipv6_addr_equal(remote, &t->parms.raddr) || 151 !ipv6_addr_any(&t->parms.laddr) || 152 !(t->dev->flags & IFF_UP)) 153 continue; 154 155 if (link == t->parms.link) 156 return t; 157 else if (!cand) 158 cand = t; 159 } 160 161 if (cand) 162 return cand; 163 164 t = rcu_dereference(ip6n->collect_md_tun); 165 if (t && t->dev->flags & IFF_UP) 166 return t; 167 168 t = rcu_dereference(ip6n->tnls_wc[0]); 169 if (t && (t->dev->flags & IFF_UP)) 170 return t; 171 172 return NULL; 173 } 174 175 /** 176 * ip6_tnl_bucket - get head of list matching given tunnel parameters 177 * @ip6n: the private data for ip6_vti in the netns 178 * @p: parameters containing tunnel end-points 179 * 180 * Description: 181 * ip6_tnl_bucket() returns the head of the list matching the 182 * &struct in6_addr entries laddr and raddr in @p. 183 * 184 * Return: head of IPv6 tunnel list 185 **/ 186 187 static struct ip6_tnl __rcu ** 188 ip6_tnl_bucket(struct ip6_tnl_net *ip6n, const struct __ip6_tnl_parm *p) 189 { 190 const struct in6_addr *remote = &p->raddr; 191 const struct in6_addr *local = &p->laddr; 192 unsigned int h = 0; 193 int prio = 0; 194 195 if (!ipv6_addr_any(remote) || !ipv6_addr_any(local)) { 196 prio = 1; 197 h = HASH(remote, local); 198 } 199 return &ip6n->tnls[prio][h]; 200 } 201 202 /** 203 * ip6_tnl_link - add tunnel to hash table 204 * @ip6n: the private data for ip6_vti in the netns 205 * @t: tunnel to be added 206 **/ 207 208 static void 209 ip6_tnl_link(struct ip6_tnl_net *ip6n, struct ip6_tnl *t) 210 { 211 struct ip6_tnl __rcu **tp = ip6_tnl_bucket(ip6n, &t->parms); 212 213 if (t->parms.collect_md) 214 rcu_assign_pointer(ip6n->collect_md_tun, t); 215 rcu_assign_pointer(t->next , rtnl_dereference(*tp)); 216 rcu_assign_pointer(*tp, t); 217 } 218 219 /** 220 * ip6_tnl_unlink - remove tunnel from hash table 221 * @ip6n: the private data for ip6_vti in the netns 222 * @t: tunnel to be removed 223 **/ 224 225 static void 226 ip6_tnl_unlink(struct ip6_tnl_net *ip6n, struct ip6_tnl *t) 227 { 228 struct ip6_tnl __rcu **tp; 229 struct ip6_tnl *iter; 230 231 if (t->parms.collect_md) 232 rcu_assign_pointer(ip6n->collect_md_tun, NULL); 233 234 for (tp = ip6_tnl_bucket(ip6n, &t->parms); 235 (iter = rtnl_dereference(*tp)) != NULL; 236 tp = &iter->next) { 237 if (t == iter) { 238 rcu_assign_pointer(*tp, t->next); 239 break; 240 } 241 } 242 } 243 244 static void ip6_dev_free(struct net_device *dev) 245 { 246 struct ip6_tnl *t = netdev_priv(dev); 247 248 gro_cells_destroy(&t->gro_cells); 249 dst_cache_destroy(&t->dst_cache); 250 free_percpu(dev->tstats); 251 } 252 253 static int ip6_tnl_create2(struct net_device *dev) 254 { 255 struct ip6_tnl *t = netdev_priv(dev); 256 struct net *net = dev_net(dev); 257 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 258 int err; 259 260 t = netdev_priv(dev); 261 262 dev->rtnl_link_ops = &ip6_link_ops; 263 err = register_netdevice(dev); 264 if (err < 0) 265 goto out; 266 267 strcpy(t->parms.name, dev->name); 268 269 dev_hold(dev); 270 ip6_tnl_link(ip6n, t); 271 return 0; 272 273 out: 274 return err; 275 } 276 277 /** 278 * ip6_tnl_create - create a new tunnel 279 * @net: network namespace 280 * @p: tunnel parameters 281 * 282 * Description: 283 * Create tunnel matching given parameters. 284 * 285 * Return: 286 * created tunnel or error pointer 287 **/ 288 289 static struct ip6_tnl *ip6_tnl_create(struct net *net, struct __ip6_tnl_parm *p) 290 { 291 struct net_device *dev; 292 struct ip6_tnl *t; 293 char name[IFNAMSIZ]; 294 int err = -E2BIG; 295 296 if (p->name[0]) { 297 if (!dev_valid_name(p->name)) 298 goto failed; 299 strlcpy(name, p->name, IFNAMSIZ); 300 } else { 301 sprintf(name, "ip6tnl%%d"); 302 } 303 err = -ENOMEM; 304 dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN, 305 ip6_tnl_dev_setup); 306 if (!dev) 307 goto failed; 308 309 dev_net_set(dev, net); 310 311 t = netdev_priv(dev); 312 t->parms = *p; 313 t->net = dev_net(dev); 314 err = ip6_tnl_create2(dev); 315 if (err < 0) 316 goto failed_free; 317 318 return t; 319 320 failed_free: 321 free_netdev(dev); 322 failed: 323 return ERR_PTR(err); 324 } 325 326 /** 327 * ip6_tnl_locate - find or create tunnel matching given parameters 328 * @net: network namespace 329 * @p: tunnel parameters 330 * @create: != 0 if allowed to create new tunnel if no match found 331 * 332 * Description: 333 * ip6_tnl_locate() first tries to locate an existing tunnel 334 * based on @parms. If this is unsuccessful, but @create is set a new 335 * tunnel device is created and registered for use. 336 * 337 * Return: 338 * matching tunnel or error pointer 339 **/ 340 341 static struct ip6_tnl *ip6_tnl_locate(struct net *net, 342 struct __ip6_tnl_parm *p, int create) 343 { 344 const struct in6_addr *remote = &p->raddr; 345 const struct in6_addr *local = &p->laddr; 346 struct ip6_tnl __rcu **tp; 347 struct ip6_tnl *t; 348 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 349 350 for (tp = ip6_tnl_bucket(ip6n, p); 351 (t = rtnl_dereference(*tp)) != NULL; 352 tp = &t->next) { 353 if (ipv6_addr_equal(local, &t->parms.laddr) && 354 ipv6_addr_equal(remote, &t->parms.raddr) && 355 p->link == t->parms.link) { 356 if (create) 357 return ERR_PTR(-EEXIST); 358 359 return t; 360 } 361 } 362 if (!create) 363 return ERR_PTR(-ENODEV); 364 return ip6_tnl_create(net, p); 365 } 366 367 /** 368 * ip6_tnl_dev_uninit - tunnel device uninitializer 369 * @dev: the device to be destroyed 370 * 371 * Description: 372 * ip6_tnl_dev_uninit() removes tunnel from its list 373 **/ 374 375 static void 376 ip6_tnl_dev_uninit(struct net_device *dev) 377 { 378 struct ip6_tnl *t = netdev_priv(dev); 379 struct net *net = t->net; 380 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 381 382 if (dev == ip6n->fb_tnl_dev) 383 RCU_INIT_POINTER(ip6n->tnls_wc[0], NULL); 384 else 385 ip6_tnl_unlink(ip6n, t); 386 dst_cache_reset(&t->dst_cache); 387 dev_put(dev); 388 } 389 390 /** 391 * parse_tvl_tnl_enc_lim - handle encapsulation limit option 392 * @skb: received socket buffer 393 * @raw: the ICMPv6 error message data 394 * 395 * Return: 396 * 0 if none was found, 397 * else index to encapsulation limit 398 **/ 399 400 __u16 ip6_tnl_parse_tlv_enc_lim(struct sk_buff *skb, __u8 *raw) 401 { 402 const struct ipv6hdr *ipv6h = (const struct ipv6hdr *)raw; 403 unsigned int nhoff = raw - skb->data; 404 unsigned int off = nhoff + sizeof(*ipv6h); 405 u8 next, nexthdr = ipv6h->nexthdr; 406 407 while (ipv6_ext_hdr(nexthdr) && nexthdr != NEXTHDR_NONE) { 408 struct ipv6_opt_hdr *hdr; 409 u16 optlen; 410 411 if (!pskb_may_pull(skb, off + sizeof(*hdr))) 412 break; 413 414 hdr = (struct ipv6_opt_hdr *)(skb->data + off); 415 if (nexthdr == NEXTHDR_FRAGMENT) { 416 struct frag_hdr *frag_hdr = (struct frag_hdr *) hdr; 417 if (frag_hdr->frag_off) 418 break; 419 optlen = 8; 420 } else if (nexthdr == NEXTHDR_AUTH) { 421 optlen = ipv6_authlen(hdr); 422 } else { 423 optlen = ipv6_optlen(hdr); 424 } 425 /* cache hdr->nexthdr, since pskb_may_pull() might 426 * invalidate hdr 427 */ 428 next = hdr->nexthdr; 429 if (nexthdr == NEXTHDR_DEST) { 430 u16 i = 2; 431 432 /* Remember : hdr is no longer valid at this point. */ 433 if (!pskb_may_pull(skb, off + optlen)) 434 break; 435 436 while (1) { 437 struct ipv6_tlv_tnl_enc_lim *tel; 438 439 /* No more room for encapsulation limit */ 440 if (i + sizeof(*tel) > optlen) 441 break; 442 443 tel = (struct ipv6_tlv_tnl_enc_lim *)(skb->data + off + i); 444 /* return index of option if found and valid */ 445 if (tel->type == IPV6_TLV_TNL_ENCAP_LIMIT && 446 tel->length == 1) 447 return i + off - nhoff; 448 /* else jump to next option */ 449 if (tel->type) 450 i += tel->length + 2; 451 else 452 i++; 453 } 454 } 455 nexthdr = next; 456 off += optlen; 457 } 458 return 0; 459 } 460 EXPORT_SYMBOL(ip6_tnl_parse_tlv_enc_lim); 461 462 /* ip6_tnl_err() should handle errors in the tunnel according to the 463 * specifications in RFC 2473. 464 */ 465 static int 466 ip6_tnl_err(struct sk_buff *skb, __u8 ipproto, struct inet6_skb_parm *opt, 467 u8 *type, u8 *code, int *msg, __u32 *info, int offset) 468 { 469 const struct ipv6hdr *ipv6h = (const struct ipv6hdr *)skb->data; 470 struct net *net = dev_net(skb->dev); 471 u8 rel_type = ICMPV6_DEST_UNREACH; 472 u8 rel_code = ICMPV6_ADDR_UNREACH; 473 __u32 rel_info = 0; 474 struct ip6_tnl *t; 475 int err = -ENOENT; 476 int rel_msg = 0; 477 u8 tproto; 478 __u16 len; 479 480 /* If the packet doesn't contain the original IPv6 header we are 481 in trouble since we might need the source address for further 482 processing of the error. */ 483 484 rcu_read_lock(); 485 t = ip6_tnl_lookup(dev_net(skb->dev), skb->dev->ifindex, &ipv6h->daddr, &ipv6h->saddr); 486 if (!t) 487 goto out; 488 489 tproto = READ_ONCE(t->parms.proto); 490 if (tproto != ipproto && tproto != 0) 491 goto out; 492 493 err = 0; 494 495 switch (*type) { 496 case ICMPV6_DEST_UNREACH: 497 net_dbg_ratelimited("%s: Path to destination invalid or inactive!\n", 498 t->parms.name); 499 rel_msg = 1; 500 break; 501 case ICMPV6_TIME_EXCEED: 502 if ((*code) == ICMPV6_EXC_HOPLIMIT) { 503 net_dbg_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n", 504 t->parms.name); 505 rel_msg = 1; 506 } 507 break; 508 case ICMPV6_PARAMPROB: { 509 struct ipv6_tlv_tnl_enc_lim *tel; 510 __u32 teli; 511 512 teli = 0; 513 if ((*code) == ICMPV6_HDR_FIELD) 514 teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data); 515 516 if (teli && teli == *info - 2) { 517 tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli]; 518 if (tel->encap_limit == 0) { 519 net_dbg_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n", 520 t->parms.name); 521 rel_msg = 1; 522 } 523 } else { 524 net_dbg_ratelimited("%s: Recipient unable to parse tunneled packet!\n", 525 t->parms.name); 526 } 527 break; 528 } 529 case ICMPV6_PKT_TOOBIG: { 530 __u32 mtu; 531 532 ip6_update_pmtu(skb, net, htonl(*info), 0, 0, 533 sock_net_uid(net, NULL)); 534 mtu = *info - offset; 535 if (mtu < IPV6_MIN_MTU) 536 mtu = IPV6_MIN_MTU; 537 len = sizeof(*ipv6h) + ntohs(ipv6h->payload_len); 538 if (len > mtu) { 539 rel_type = ICMPV6_PKT_TOOBIG; 540 rel_code = 0; 541 rel_info = mtu; 542 rel_msg = 1; 543 } 544 break; 545 } 546 case NDISC_REDIRECT: 547 ip6_redirect(skb, net, skb->dev->ifindex, 0, 548 sock_net_uid(net, NULL)); 549 break; 550 } 551 552 *type = rel_type; 553 *code = rel_code; 554 *info = rel_info; 555 *msg = rel_msg; 556 557 out: 558 rcu_read_unlock(); 559 return err; 560 } 561 562 static int 563 ip4ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 564 u8 type, u8 code, int offset, __be32 info) 565 { 566 __u32 rel_info = ntohl(info); 567 const struct iphdr *eiph; 568 struct sk_buff *skb2; 569 int err, rel_msg = 0; 570 u8 rel_type = type; 571 u8 rel_code = code; 572 struct rtable *rt; 573 struct flowi4 fl4; 574 575 err = ip6_tnl_err(skb, IPPROTO_IPIP, opt, &rel_type, &rel_code, 576 &rel_msg, &rel_info, offset); 577 if (err < 0) 578 return err; 579 580 if (rel_msg == 0) 581 return 0; 582 583 switch (rel_type) { 584 case ICMPV6_DEST_UNREACH: 585 if (rel_code != ICMPV6_ADDR_UNREACH) 586 return 0; 587 rel_type = ICMP_DEST_UNREACH; 588 rel_code = ICMP_HOST_UNREACH; 589 break; 590 case ICMPV6_PKT_TOOBIG: 591 if (rel_code != 0) 592 return 0; 593 rel_type = ICMP_DEST_UNREACH; 594 rel_code = ICMP_FRAG_NEEDED; 595 break; 596 default: 597 return 0; 598 } 599 600 if (!pskb_may_pull(skb, offset + sizeof(struct iphdr))) 601 return 0; 602 603 skb2 = skb_clone(skb, GFP_ATOMIC); 604 if (!skb2) 605 return 0; 606 607 skb_dst_drop(skb2); 608 609 skb_pull(skb2, offset); 610 skb_reset_network_header(skb2); 611 eiph = ip_hdr(skb2); 612 613 /* Try to guess incoming interface */ 614 rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL, eiph->saddr, 615 0, 0, 0, IPPROTO_IPIP, RT_TOS(eiph->tos), 0); 616 if (IS_ERR(rt)) 617 goto out; 618 619 skb2->dev = rt->dst.dev; 620 ip_rt_put(rt); 621 622 /* route "incoming" packet */ 623 if (rt->rt_flags & RTCF_LOCAL) { 624 rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL, 625 eiph->daddr, eiph->saddr, 0, 0, 626 IPPROTO_IPIP, RT_TOS(eiph->tos), 0); 627 if (IS_ERR(rt) || rt->dst.dev->type != ARPHRD_TUNNEL6) { 628 if (!IS_ERR(rt)) 629 ip_rt_put(rt); 630 goto out; 631 } 632 skb_dst_set(skb2, &rt->dst); 633 } else { 634 if (ip_route_input(skb2, eiph->daddr, eiph->saddr, eiph->tos, 635 skb2->dev) || 636 skb_dst(skb2)->dev->type != ARPHRD_TUNNEL6) 637 goto out; 638 } 639 640 /* change mtu on this route */ 641 if (rel_type == ICMP_DEST_UNREACH && rel_code == ICMP_FRAG_NEEDED) { 642 if (rel_info > dst_mtu(skb_dst(skb2))) 643 goto out; 644 645 skb_dst_update_pmtu_no_confirm(skb2, rel_info); 646 } 647 648 icmp_send(skb2, rel_type, rel_code, htonl(rel_info)); 649 650 out: 651 kfree_skb(skb2); 652 return 0; 653 } 654 655 static int 656 ip6ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 657 u8 type, u8 code, int offset, __be32 info) 658 { 659 __u32 rel_info = ntohl(info); 660 int err, rel_msg = 0; 661 u8 rel_type = type; 662 u8 rel_code = code; 663 664 err = ip6_tnl_err(skb, IPPROTO_IPV6, opt, &rel_type, &rel_code, 665 &rel_msg, &rel_info, offset); 666 if (err < 0) 667 return err; 668 669 if (rel_msg && pskb_may_pull(skb, offset + sizeof(struct ipv6hdr))) { 670 struct rt6_info *rt; 671 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC); 672 673 if (!skb2) 674 return 0; 675 676 skb_dst_drop(skb2); 677 skb_pull(skb2, offset); 678 skb_reset_network_header(skb2); 679 680 /* Try to guess incoming interface */ 681 rt = rt6_lookup(dev_net(skb->dev), &ipv6_hdr(skb2)->saddr, 682 NULL, 0, skb2, 0); 683 684 if (rt && rt->dst.dev) 685 skb2->dev = rt->dst.dev; 686 687 icmpv6_send(skb2, rel_type, rel_code, rel_info); 688 689 ip6_rt_put(rt); 690 691 kfree_skb(skb2); 692 } 693 694 return 0; 695 } 696 697 static int 698 mplsip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 699 u8 type, u8 code, int offset, __be32 info) 700 { 701 __u32 rel_info = ntohl(info); 702 int err, rel_msg = 0; 703 u8 rel_type = type; 704 u8 rel_code = code; 705 706 err = ip6_tnl_err(skb, IPPROTO_MPLS, opt, &rel_type, &rel_code, 707 &rel_msg, &rel_info, offset); 708 return err; 709 } 710 711 static int ip4ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t, 712 const struct ipv6hdr *ipv6h, 713 struct sk_buff *skb) 714 { 715 __u8 dsfield = ipv6_get_dsfield(ipv6h) & ~INET_ECN_MASK; 716 717 if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY) 718 ipv4_change_dsfield(ip_hdr(skb), INET_ECN_MASK, dsfield); 719 720 return IP6_ECN_decapsulate(ipv6h, skb); 721 } 722 723 static int ip6ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t, 724 const struct ipv6hdr *ipv6h, 725 struct sk_buff *skb) 726 { 727 if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY) 728 ipv6_copy_dscp(ipv6_get_dsfield(ipv6h), ipv6_hdr(skb)); 729 730 return IP6_ECN_decapsulate(ipv6h, skb); 731 } 732 733 static inline int mplsip6_dscp_ecn_decapsulate(const struct ip6_tnl *t, 734 const struct ipv6hdr *ipv6h, 735 struct sk_buff *skb) 736 { 737 /* ECN is not supported in AF_MPLS */ 738 return 0; 739 } 740 741 __u32 ip6_tnl_get_cap(struct ip6_tnl *t, 742 const struct in6_addr *laddr, 743 const struct in6_addr *raddr) 744 { 745 struct __ip6_tnl_parm *p = &t->parms; 746 int ltype = ipv6_addr_type(laddr); 747 int rtype = ipv6_addr_type(raddr); 748 __u32 flags = 0; 749 750 if (ltype == IPV6_ADDR_ANY || rtype == IPV6_ADDR_ANY) { 751 flags = IP6_TNL_F_CAP_PER_PACKET; 752 } else if (ltype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) && 753 rtype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) && 754 !((ltype|rtype) & IPV6_ADDR_LOOPBACK) && 755 (!((ltype|rtype) & IPV6_ADDR_LINKLOCAL) || p->link)) { 756 if (ltype&IPV6_ADDR_UNICAST) 757 flags |= IP6_TNL_F_CAP_XMIT; 758 if (rtype&IPV6_ADDR_UNICAST) 759 flags |= IP6_TNL_F_CAP_RCV; 760 } 761 return flags; 762 } 763 EXPORT_SYMBOL(ip6_tnl_get_cap); 764 765 /* called with rcu_read_lock() */ 766 int ip6_tnl_rcv_ctl(struct ip6_tnl *t, 767 const struct in6_addr *laddr, 768 const struct in6_addr *raddr) 769 { 770 struct __ip6_tnl_parm *p = &t->parms; 771 int ret = 0; 772 struct net *net = t->net; 773 774 if ((p->flags & IP6_TNL_F_CAP_RCV) || 775 ((p->flags & IP6_TNL_F_CAP_PER_PACKET) && 776 (ip6_tnl_get_cap(t, laddr, raddr) & IP6_TNL_F_CAP_RCV))) { 777 struct net_device *ldev = NULL; 778 779 if (p->link) 780 ldev = dev_get_by_index_rcu(net, p->link); 781 782 if ((ipv6_addr_is_multicast(laddr) || 783 likely(ipv6_chk_addr_and_flags(net, laddr, ldev, false, 784 0, IFA_F_TENTATIVE))) && 785 ((p->flags & IP6_TNL_F_ALLOW_LOCAL_REMOTE) || 786 likely(!ipv6_chk_addr_and_flags(net, raddr, ldev, true, 787 0, IFA_F_TENTATIVE)))) 788 ret = 1; 789 } 790 return ret; 791 } 792 EXPORT_SYMBOL_GPL(ip6_tnl_rcv_ctl); 793 794 static int __ip6_tnl_rcv(struct ip6_tnl *tunnel, struct sk_buff *skb, 795 const struct tnl_ptk_info *tpi, 796 struct metadata_dst *tun_dst, 797 int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t, 798 const struct ipv6hdr *ipv6h, 799 struct sk_buff *skb), 800 bool log_ecn_err) 801 { 802 struct pcpu_sw_netstats *tstats; 803 const struct ipv6hdr *ipv6h = ipv6_hdr(skb); 804 int err; 805 806 if ((!(tpi->flags & TUNNEL_CSUM) && 807 (tunnel->parms.i_flags & TUNNEL_CSUM)) || 808 ((tpi->flags & TUNNEL_CSUM) && 809 !(tunnel->parms.i_flags & TUNNEL_CSUM))) { 810 tunnel->dev->stats.rx_crc_errors++; 811 tunnel->dev->stats.rx_errors++; 812 goto drop; 813 } 814 815 if (tunnel->parms.i_flags & TUNNEL_SEQ) { 816 if (!(tpi->flags & TUNNEL_SEQ) || 817 (tunnel->i_seqno && 818 (s32)(ntohl(tpi->seq) - tunnel->i_seqno) < 0)) { 819 tunnel->dev->stats.rx_fifo_errors++; 820 tunnel->dev->stats.rx_errors++; 821 goto drop; 822 } 823 tunnel->i_seqno = ntohl(tpi->seq) + 1; 824 } 825 826 skb->protocol = tpi->proto; 827 828 /* Warning: All skb pointers will be invalidated! */ 829 if (tunnel->dev->type == ARPHRD_ETHER) { 830 if (!pskb_may_pull(skb, ETH_HLEN)) { 831 tunnel->dev->stats.rx_length_errors++; 832 tunnel->dev->stats.rx_errors++; 833 goto drop; 834 } 835 836 ipv6h = ipv6_hdr(skb); 837 skb->protocol = eth_type_trans(skb, tunnel->dev); 838 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN); 839 } else { 840 skb->dev = tunnel->dev; 841 } 842 843 skb_reset_network_header(skb); 844 memset(skb->cb, 0, sizeof(struct inet6_skb_parm)); 845 846 __skb_tunnel_rx(skb, tunnel->dev, tunnel->net); 847 848 err = dscp_ecn_decapsulate(tunnel, ipv6h, skb); 849 if (unlikely(err)) { 850 if (log_ecn_err) 851 net_info_ratelimited("non-ECT from %pI6 with DS=%#x\n", 852 &ipv6h->saddr, 853 ipv6_get_dsfield(ipv6h)); 854 if (err > 1) { 855 ++tunnel->dev->stats.rx_frame_errors; 856 ++tunnel->dev->stats.rx_errors; 857 goto drop; 858 } 859 } 860 861 tstats = this_cpu_ptr(tunnel->dev->tstats); 862 u64_stats_update_begin(&tstats->syncp); 863 tstats->rx_packets++; 864 tstats->rx_bytes += skb->len; 865 u64_stats_update_end(&tstats->syncp); 866 867 skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(tunnel->dev))); 868 869 if (tun_dst) 870 skb_dst_set(skb, (struct dst_entry *)tun_dst); 871 872 gro_cells_receive(&tunnel->gro_cells, skb); 873 return 0; 874 875 drop: 876 if (tun_dst) 877 dst_release((struct dst_entry *)tun_dst); 878 kfree_skb(skb); 879 return 0; 880 } 881 882 int ip6_tnl_rcv(struct ip6_tnl *t, struct sk_buff *skb, 883 const struct tnl_ptk_info *tpi, 884 struct metadata_dst *tun_dst, 885 bool log_ecn_err) 886 { 887 int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t, 888 const struct ipv6hdr *ipv6h, 889 struct sk_buff *skb); 890 891 dscp_ecn_decapsulate = ip6ip6_dscp_ecn_decapsulate; 892 if (tpi->proto == htons(ETH_P_IP)) 893 dscp_ecn_decapsulate = ip4ip6_dscp_ecn_decapsulate; 894 895 return __ip6_tnl_rcv(t, skb, tpi, tun_dst, dscp_ecn_decapsulate, 896 log_ecn_err); 897 } 898 EXPORT_SYMBOL(ip6_tnl_rcv); 899 900 static const struct tnl_ptk_info tpi_v6 = { 901 /* no tunnel info required for ipxip6. */ 902 .proto = htons(ETH_P_IPV6), 903 }; 904 905 static const struct tnl_ptk_info tpi_v4 = { 906 /* no tunnel info required for ipxip6. */ 907 .proto = htons(ETH_P_IP), 908 }; 909 910 static const struct tnl_ptk_info tpi_mpls = { 911 /* no tunnel info required for mplsip6. */ 912 .proto = htons(ETH_P_MPLS_UC), 913 }; 914 915 static int ipxip6_rcv(struct sk_buff *skb, u8 ipproto, 916 const struct tnl_ptk_info *tpi, 917 int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t, 918 const struct ipv6hdr *ipv6h, 919 struct sk_buff *skb)) 920 { 921 struct ip6_tnl *t; 922 const struct ipv6hdr *ipv6h = ipv6_hdr(skb); 923 struct metadata_dst *tun_dst = NULL; 924 int ret = -1; 925 926 rcu_read_lock(); 927 t = ip6_tnl_lookup(dev_net(skb->dev), skb->dev->ifindex, &ipv6h->saddr, &ipv6h->daddr); 928 929 if (t) { 930 u8 tproto = READ_ONCE(t->parms.proto); 931 932 if (tproto != ipproto && tproto != 0) 933 goto drop; 934 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) 935 goto drop; 936 ipv6h = ipv6_hdr(skb); 937 if (!ip6_tnl_rcv_ctl(t, &ipv6h->daddr, &ipv6h->saddr)) 938 goto drop; 939 if (iptunnel_pull_header(skb, 0, tpi->proto, false)) 940 goto drop; 941 if (t->parms.collect_md) { 942 tun_dst = ipv6_tun_rx_dst(skb, 0, 0, 0); 943 if (!tun_dst) 944 goto drop; 945 } 946 ret = __ip6_tnl_rcv(t, skb, tpi, tun_dst, dscp_ecn_decapsulate, 947 log_ecn_error); 948 } 949 950 rcu_read_unlock(); 951 952 return ret; 953 954 drop: 955 rcu_read_unlock(); 956 kfree_skb(skb); 957 return 0; 958 } 959 960 static int ip4ip6_rcv(struct sk_buff *skb) 961 { 962 return ipxip6_rcv(skb, IPPROTO_IPIP, &tpi_v4, 963 ip4ip6_dscp_ecn_decapsulate); 964 } 965 966 static int ip6ip6_rcv(struct sk_buff *skb) 967 { 968 return ipxip6_rcv(skb, IPPROTO_IPV6, &tpi_v6, 969 ip6ip6_dscp_ecn_decapsulate); 970 } 971 972 static int mplsip6_rcv(struct sk_buff *skb) 973 { 974 return ipxip6_rcv(skb, IPPROTO_MPLS, &tpi_mpls, 975 mplsip6_dscp_ecn_decapsulate); 976 } 977 978 struct ipv6_tel_txoption { 979 struct ipv6_txoptions ops; 980 __u8 dst_opt[8]; 981 }; 982 983 static void init_tel_txopt(struct ipv6_tel_txoption *opt, __u8 encap_limit) 984 { 985 memset(opt, 0, sizeof(struct ipv6_tel_txoption)); 986 987 opt->dst_opt[2] = IPV6_TLV_TNL_ENCAP_LIMIT; 988 opt->dst_opt[3] = 1; 989 opt->dst_opt[4] = encap_limit; 990 opt->dst_opt[5] = IPV6_TLV_PADN; 991 opt->dst_opt[6] = 1; 992 993 opt->ops.dst1opt = (struct ipv6_opt_hdr *) opt->dst_opt; 994 opt->ops.opt_nflen = 8; 995 } 996 997 /** 998 * ip6_tnl_addr_conflict - compare packet addresses to tunnel's own 999 * @t: the outgoing tunnel device 1000 * @hdr: IPv6 header from the incoming packet 1001 * 1002 * Description: 1003 * Avoid trivial tunneling loop by checking that tunnel exit-point 1004 * doesn't match source of incoming packet. 1005 * 1006 * Return: 1007 * 1 if conflict, 1008 * 0 else 1009 **/ 1010 1011 static inline bool 1012 ip6_tnl_addr_conflict(const struct ip6_tnl *t, const struct ipv6hdr *hdr) 1013 { 1014 return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr); 1015 } 1016 1017 int ip6_tnl_xmit_ctl(struct ip6_tnl *t, 1018 const struct in6_addr *laddr, 1019 const struct in6_addr *raddr) 1020 { 1021 struct __ip6_tnl_parm *p = &t->parms; 1022 int ret = 0; 1023 struct net *net = t->net; 1024 1025 if (t->parms.collect_md) 1026 return 1; 1027 1028 if ((p->flags & IP6_TNL_F_CAP_XMIT) || 1029 ((p->flags & IP6_TNL_F_CAP_PER_PACKET) && 1030 (ip6_tnl_get_cap(t, laddr, raddr) & IP6_TNL_F_CAP_XMIT))) { 1031 struct net_device *ldev = NULL; 1032 1033 rcu_read_lock(); 1034 if (p->link) 1035 ldev = dev_get_by_index_rcu(net, p->link); 1036 1037 if (unlikely(!ipv6_chk_addr_and_flags(net, laddr, ldev, false, 1038 0, IFA_F_TENTATIVE))) 1039 pr_warn("%s xmit: Local address not yet configured!\n", 1040 p->name); 1041 else if (!(p->flags & IP6_TNL_F_ALLOW_LOCAL_REMOTE) && 1042 !ipv6_addr_is_multicast(raddr) && 1043 unlikely(ipv6_chk_addr_and_flags(net, raddr, ldev, 1044 true, 0, IFA_F_TENTATIVE))) 1045 pr_warn("%s xmit: Routing loop! Remote address found on this node!\n", 1046 p->name); 1047 else 1048 ret = 1; 1049 rcu_read_unlock(); 1050 } 1051 return ret; 1052 } 1053 EXPORT_SYMBOL_GPL(ip6_tnl_xmit_ctl); 1054 1055 /** 1056 * ip6_tnl_xmit - encapsulate packet and send 1057 * @skb: the outgoing socket buffer 1058 * @dev: the outgoing tunnel device 1059 * @dsfield: dscp code for outer header 1060 * @fl6: flow of tunneled packet 1061 * @encap_limit: encapsulation limit 1062 * @pmtu: Path MTU is stored if packet is too big 1063 * @proto: next header value 1064 * 1065 * Description: 1066 * Build new header and do some sanity checks on the packet before sending 1067 * it. 1068 * 1069 * Return: 1070 * 0 on success 1071 * -1 fail 1072 * %-EMSGSIZE message too big. return mtu in this case. 1073 **/ 1074 1075 int ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev, __u8 dsfield, 1076 struct flowi6 *fl6, int encap_limit, __u32 *pmtu, 1077 __u8 proto) 1078 { 1079 struct ip6_tnl *t = netdev_priv(dev); 1080 struct net *net = t->net; 1081 struct net_device_stats *stats = &t->dev->stats; 1082 struct ipv6hdr *ipv6h; 1083 struct ipv6_tel_txoption opt; 1084 struct dst_entry *dst = NULL, *ndst = NULL; 1085 struct net_device *tdev; 1086 int mtu; 1087 unsigned int eth_hlen = t->dev->type == ARPHRD_ETHER ? ETH_HLEN : 0; 1088 unsigned int psh_hlen = sizeof(struct ipv6hdr) + t->encap_hlen; 1089 unsigned int max_headroom = psh_hlen; 1090 bool use_cache = false; 1091 u8 hop_limit; 1092 int err = -1; 1093 1094 if (t->parms.collect_md) { 1095 hop_limit = skb_tunnel_info(skb)->key.ttl; 1096 goto route_lookup; 1097 } else { 1098 hop_limit = t->parms.hop_limit; 1099 } 1100 1101 /* NBMA tunnel */ 1102 if (ipv6_addr_any(&t->parms.raddr)) { 1103 if (skb->protocol == htons(ETH_P_IPV6)) { 1104 struct in6_addr *addr6; 1105 struct neighbour *neigh; 1106 int addr_type; 1107 1108 if (!skb_dst(skb)) 1109 goto tx_err_link_failure; 1110 1111 neigh = dst_neigh_lookup(skb_dst(skb), 1112 &ipv6_hdr(skb)->daddr); 1113 if (!neigh) 1114 goto tx_err_link_failure; 1115 1116 addr6 = (struct in6_addr *)&neigh->primary_key; 1117 addr_type = ipv6_addr_type(addr6); 1118 1119 if (addr_type == IPV6_ADDR_ANY) 1120 addr6 = &ipv6_hdr(skb)->daddr; 1121 1122 memcpy(&fl6->daddr, addr6, sizeof(fl6->daddr)); 1123 neigh_release(neigh); 1124 } 1125 } else if (t->parms.proto != 0 && !(t->parms.flags & 1126 (IP6_TNL_F_USE_ORIG_TCLASS | 1127 IP6_TNL_F_USE_ORIG_FWMARK))) { 1128 /* enable the cache only if neither the outer protocol nor the 1129 * routing decision depends on the current inner header value 1130 */ 1131 use_cache = true; 1132 } 1133 1134 if (use_cache) 1135 dst = dst_cache_get(&t->dst_cache); 1136 1137 if (!ip6_tnl_xmit_ctl(t, &fl6->saddr, &fl6->daddr)) 1138 goto tx_err_link_failure; 1139 1140 if (!dst) { 1141 route_lookup: 1142 /* add dsfield to flowlabel for route lookup */ 1143 fl6->flowlabel = ip6_make_flowinfo(dsfield, fl6->flowlabel); 1144 1145 dst = ip6_route_output(net, NULL, fl6); 1146 1147 if (dst->error) 1148 goto tx_err_link_failure; 1149 dst = xfrm_lookup(net, dst, flowi6_to_flowi(fl6), NULL, 0); 1150 if (IS_ERR(dst)) { 1151 err = PTR_ERR(dst); 1152 dst = NULL; 1153 goto tx_err_link_failure; 1154 } 1155 if (t->parms.collect_md && ipv6_addr_any(&fl6->saddr) && 1156 ipv6_dev_get_saddr(net, ip6_dst_idev(dst)->dev, 1157 &fl6->daddr, 0, &fl6->saddr)) 1158 goto tx_err_link_failure; 1159 ndst = dst; 1160 } 1161 1162 tdev = dst->dev; 1163 1164 if (tdev == dev) { 1165 stats->collisions++; 1166 net_warn_ratelimited("%s: Local routing loop detected!\n", 1167 t->parms.name); 1168 goto tx_err_dst_release; 1169 } 1170 mtu = dst_mtu(dst) - eth_hlen - psh_hlen - t->tun_hlen; 1171 if (encap_limit >= 0) { 1172 max_headroom += 8; 1173 mtu -= 8; 1174 } 1175 mtu = max(mtu, skb->protocol == htons(ETH_P_IPV6) ? 1176 IPV6_MIN_MTU : IPV4_MIN_MTU); 1177 1178 skb_dst_update_pmtu_no_confirm(skb, mtu); 1179 if (skb->len - t->tun_hlen - eth_hlen > mtu && !skb_is_gso(skb)) { 1180 *pmtu = mtu; 1181 err = -EMSGSIZE; 1182 goto tx_err_dst_release; 1183 } 1184 1185 if (t->err_count > 0) { 1186 if (time_before(jiffies, 1187 t->err_time + IP6TUNNEL_ERR_TIMEO)) { 1188 t->err_count--; 1189 1190 dst_link_failure(skb); 1191 } else { 1192 t->err_count = 0; 1193 } 1194 } 1195 1196 skb_scrub_packet(skb, !net_eq(t->net, dev_net(dev))); 1197 1198 /* 1199 * Okay, now see if we can stuff it in the buffer as-is. 1200 */ 1201 max_headroom += LL_RESERVED_SPACE(tdev); 1202 1203 if (skb_headroom(skb) < max_headroom || skb_shared(skb) || 1204 (skb_cloned(skb) && !skb_clone_writable(skb, 0))) { 1205 struct sk_buff *new_skb; 1206 1207 new_skb = skb_realloc_headroom(skb, max_headroom); 1208 if (!new_skb) 1209 goto tx_err_dst_release; 1210 1211 if (skb->sk) 1212 skb_set_owner_w(new_skb, skb->sk); 1213 consume_skb(skb); 1214 skb = new_skb; 1215 } 1216 1217 if (t->parms.collect_md) { 1218 if (t->encap.type != TUNNEL_ENCAP_NONE) 1219 goto tx_err_dst_release; 1220 } else { 1221 if (use_cache && ndst) 1222 dst_cache_set_ip6(&t->dst_cache, ndst, &fl6->saddr); 1223 } 1224 skb_dst_set(skb, dst); 1225 1226 if (hop_limit == 0) { 1227 if (skb->protocol == htons(ETH_P_IP)) 1228 hop_limit = ip_hdr(skb)->ttl; 1229 else if (skb->protocol == htons(ETH_P_IPV6)) 1230 hop_limit = ipv6_hdr(skb)->hop_limit; 1231 else 1232 hop_limit = ip6_dst_hoplimit(dst); 1233 } 1234 1235 /* Calculate max headroom for all the headers and adjust 1236 * needed_headroom if necessary. 1237 */ 1238 max_headroom = LL_RESERVED_SPACE(dst->dev) + sizeof(struct ipv6hdr) 1239 + dst->header_len + t->hlen; 1240 if (max_headroom > dev->needed_headroom) 1241 dev->needed_headroom = max_headroom; 1242 1243 skb_set_inner_ipproto(skb, proto); 1244 1245 err = ip6_tnl_encap(skb, t, &proto, fl6); 1246 if (err) 1247 return err; 1248 1249 if (encap_limit >= 0) { 1250 init_tel_txopt(&opt, encap_limit); 1251 ipv6_push_frag_opts(skb, &opt.ops, &proto); 1252 } 1253 1254 skb_push(skb, sizeof(struct ipv6hdr)); 1255 skb_reset_network_header(skb); 1256 ipv6h = ipv6_hdr(skb); 1257 ip6_flow_hdr(ipv6h, dsfield, 1258 ip6_make_flowlabel(net, skb, fl6->flowlabel, true, fl6)); 1259 ipv6h->hop_limit = hop_limit; 1260 ipv6h->nexthdr = proto; 1261 ipv6h->saddr = fl6->saddr; 1262 ipv6h->daddr = fl6->daddr; 1263 ip6tunnel_xmit(NULL, skb, dev); 1264 return 0; 1265 tx_err_link_failure: 1266 stats->tx_carrier_errors++; 1267 dst_link_failure(skb); 1268 tx_err_dst_release: 1269 dst_release(dst); 1270 return err; 1271 } 1272 EXPORT_SYMBOL(ip6_tnl_xmit); 1273 1274 static inline int 1275 ipxip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev, 1276 u8 protocol) 1277 { 1278 struct ip6_tnl *t = netdev_priv(dev); 1279 struct ipv6hdr *ipv6h; 1280 const struct iphdr *iph; 1281 int encap_limit = -1; 1282 __u16 offset; 1283 struct flowi6 fl6; 1284 __u8 dsfield, orig_dsfield; 1285 __u32 mtu; 1286 u8 tproto; 1287 int err; 1288 1289 tproto = READ_ONCE(t->parms.proto); 1290 if (tproto != protocol && tproto != 0) 1291 return -1; 1292 1293 if (t->parms.collect_md) { 1294 struct ip_tunnel_info *tun_info; 1295 const struct ip_tunnel_key *key; 1296 1297 tun_info = skb_tunnel_info(skb); 1298 if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) || 1299 ip_tunnel_info_af(tun_info) != AF_INET6)) 1300 return -1; 1301 key = &tun_info->key; 1302 memset(&fl6, 0, sizeof(fl6)); 1303 fl6.flowi6_proto = protocol; 1304 fl6.saddr = key->u.ipv6.src; 1305 fl6.daddr = key->u.ipv6.dst; 1306 fl6.flowlabel = key->label; 1307 dsfield = key->tos; 1308 switch (protocol) { 1309 case IPPROTO_IPIP: 1310 iph = ip_hdr(skb); 1311 orig_dsfield = ipv4_get_dsfield(iph); 1312 break; 1313 case IPPROTO_IPV6: 1314 ipv6h = ipv6_hdr(skb); 1315 orig_dsfield = ipv6_get_dsfield(ipv6h); 1316 break; 1317 default: 1318 orig_dsfield = dsfield; 1319 break; 1320 } 1321 } else { 1322 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1323 encap_limit = t->parms.encap_limit; 1324 if (protocol == IPPROTO_IPV6) { 1325 offset = ip6_tnl_parse_tlv_enc_lim(skb, 1326 skb_network_header(skb)); 1327 /* ip6_tnl_parse_tlv_enc_lim() might have 1328 * reallocated skb->head 1329 */ 1330 if (offset > 0) { 1331 struct ipv6_tlv_tnl_enc_lim *tel; 1332 1333 tel = (void *)&skb_network_header(skb)[offset]; 1334 if (tel->encap_limit == 0) { 1335 icmpv6_ndo_send(skb, ICMPV6_PARAMPROB, 1336 ICMPV6_HDR_FIELD, offset + 2); 1337 return -1; 1338 } 1339 encap_limit = tel->encap_limit - 1; 1340 } 1341 } 1342 1343 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 1344 fl6.flowi6_proto = protocol; 1345 1346 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK) 1347 fl6.flowi6_mark = skb->mark; 1348 else 1349 fl6.flowi6_mark = t->parms.fwmark; 1350 switch (protocol) { 1351 case IPPROTO_IPIP: 1352 iph = ip_hdr(skb); 1353 orig_dsfield = ipv4_get_dsfield(iph); 1354 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) 1355 dsfield = orig_dsfield; 1356 else 1357 dsfield = ip6_tclass(t->parms.flowinfo); 1358 break; 1359 case IPPROTO_IPV6: 1360 ipv6h = ipv6_hdr(skb); 1361 orig_dsfield = ipv6_get_dsfield(ipv6h); 1362 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) 1363 dsfield = orig_dsfield; 1364 else 1365 dsfield = ip6_tclass(t->parms.flowinfo); 1366 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL) 1367 fl6.flowlabel |= ip6_flowlabel(ipv6h); 1368 break; 1369 default: 1370 orig_dsfield = dsfield = ip6_tclass(t->parms.flowinfo); 1371 break; 1372 } 1373 } 1374 1375 fl6.flowi6_uid = sock_net_uid(dev_net(dev), NULL); 1376 dsfield = INET_ECN_encapsulate(dsfield, orig_dsfield); 1377 1378 if (iptunnel_handle_offloads(skb, SKB_GSO_IPXIP6)) 1379 return -1; 1380 1381 err = ip6_tnl_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu, 1382 protocol); 1383 if (err != 0) { 1384 /* XXX: send ICMP error even if DF is not set. */ 1385 if (err == -EMSGSIZE) 1386 switch (protocol) { 1387 case IPPROTO_IPIP: 1388 icmp_ndo_send(skb, ICMP_DEST_UNREACH, 1389 ICMP_FRAG_NEEDED, htonl(mtu)); 1390 break; 1391 case IPPROTO_IPV6: 1392 icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); 1393 break; 1394 default: 1395 break; 1396 } 1397 return -1; 1398 } 1399 1400 return 0; 1401 } 1402 1403 static netdev_tx_t 1404 ip6_tnl_start_xmit(struct sk_buff *skb, struct net_device *dev) 1405 { 1406 struct ip6_tnl *t = netdev_priv(dev); 1407 struct net_device_stats *stats = &t->dev->stats; 1408 u8 ipproto; 1409 int ret; 1410 1411 if (!pskb_inet_may_pull(skb)) 1412 goto tx_err; 1413 1414 switch (skb->protocol) { 1415 case htons(ETH_P_IP): 1416 ipproto = IPPROTO_IPIP; 1417 break; 1418 case htons(ETH_P_IPV6): 1419 if (ip6_tnl_addr_conflict(t, ipv6_hdr(skb))) 1420 goto tx_err; 1421 ipproto = IPPROTO_IPV6; 1422 break; 1423 case htons(ETH_P_MPLS_UC): 1424 ipproto = IPPROTO_MPLS; 1425 break; 1426 default: 1427 goto tx_err; 1428 } 1429 1430 ret = ipxip6_tnl_xmit(skb, dev, ipproto); 1431 if (ret < 0) 1432 goto tx_err; 1433 1434 return NETDEV_TX_OK; 1435 1436 tx_err: 1437 stats->tx_errors++; 1438 stats->tx_dropped++; 1439 kfree_skb(skb); 1440 return NETDEV_TX_OK; 1441 } 1442 1443 static void ip6_tnl_link_config(struct ip6_tnl *t) 1444 { 1445 struct net_device *dev = t->dev; 1446 struct net_device *tdev = NULL; 1447 struct __ip6_tnl_parm *p = &t->parms; 1448 struct flowi6 *fl6 = &t->fl.u.ip6; 1449 unsigned int mtu; 1450 int t_hlen; 1451 1452 memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr)); 1453 memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr)); 1454 1455 /* Set up flowi template */ 1456 fl6->saddr = p->laddr; 1457 fl6->daddr = p->raddr; 1458 fl6->flowi6_oif = p->link; 1459 fl6->flowlabel = 0; 1460 1461 if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS)) 1462 fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo; 1463 if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL)) 1464 fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo; 1465 1466 p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET); 1467 p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr); 1468 1469 if (p->flags&IP6_TNL_F_CAP_XMIT && p->flags&IP6_TNL_F_CAP_RCV) 1470 dev->flags |= IFF_POINTOPOINT; 1471 else 1472 dev->flags &= ~IFF_POINTOPOINT; 1473 1474 t->tun_hlen = 0; 1475 t->hlen = t->encap_hlen + t->tun_hlen; 1476 t_hlen = t->hlen + sizeof(struct ipv6hdr); 1477 1478 if (p->flags & IP6_TNL_F_CAP_XMIT) { 1479 int strict = (ipv6_addr_type(&p->raddr) & 1480 (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL)); 1481 1482 struct rt6_info *rt = rt6_lookup(t->net, 1483 &p->raddr, &p->laddr, 1484 p->link, NULL, strict); 1485 if (rt) { 1486 tdev = rt->dst.dev; 1487 ip6_rt_put(rt); 1488 } 1489 1490 if (!tdev && p->link) 1491 tdev = __dev_get_by_index(t->net, p->link); 1492 1493 if (tdev) { 1494 dev->hard_header_len = tdev->hard_header_len + t_hlen; 1495 mtu = min_t(unsigned int, tdev->mtu, IP6_MAX_MTU); 1496 1497 dev->mtu = mtu - t_hlen; 1498 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1499 dev->mtu -= 8; 1500 1501 if (dev->mtu < IPV6_MIN_MTU) 1502 dev->mtu = IPV6_MIN_MTU; 1503 } 1504 } 1505 } 1506 1507 /** 1508 * ip6_tnl_change - update the tunnel parameters 1509 * @t: tunnel to be changed 1510 * @p: tunnel configuration parameters 1511 * 1512 * Description: 1513 * ip6_tnl_change() updates the tunnel parameters 1514 **/ 1515 1516 static int 1517 ip6_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p) 1518 { 1519 t->parms.laddr = p->laddr; 1520 t->parms.raddr = p->raddr; 1521 t->parms.flags = p->flags; 1522 t->parms.hop_limit = p->hop_limit; 1523 t->parms.encap_limit = p->encap_limit; 1524 t->parms.flowinfo = p->flowinfo; 1525 t->parms.link = p->link; 1526 t->parms.proto = p->proto; 1527 t->parms.fwmark = p->fwmark; 1528 dst_cache_reset(&t->dst_cache); 1529 ip6_tnl_link_config(t); 1530 return 0; 1531 } 1532 1533 static int ip6_tnl_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p) 1534 { 1535 struct net *net = t->net; 1536 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1537 int err; 1538 1539 ip6_tnl_unlink(ip6n, t); 1540 synchronize_net(); 1541 err = ip6_tnl_change(t, p); 1542 ip6_tnl_link(ip6n, t); 1543 netdev_state_change(t->dev); 1544 return err; 1545 } 1546 1547 static int ip6_tnl0_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p) 1548 { 1549 /* for default tnl0 device allow to change only the proto */ 1550 t->parms.proto = p->proto; 1551 netdev_state_change(t->dev); 1552 return 0; 1553 } 1554 1555 static void 1556 ip6_tnl_parm_from_user(struct __ip6_tnl_parm *p, const struct ip6_tnl_parm *u) 1557 { 1558 p->laddr = u->laddr; 1559 p->raddr = u->raddr; 1560 p->flags = u->flags; 1561 p->hop_limit = u->hop_limit; 1562 p->encap_limit = u->encap_limit; 1563 p->flowinfo = u->flowinfo; 1564 p->link = u->link; 1565 p->proto = u->proto; 1566 memcpy(p->name, u->name, sizeof(u->name)); 1567 } 1568 1569 static void 1570 ip6_tnl_parm_to_user(struct ip6_tnl_parm *u, const struct __ip6_tnl_parm *p) 1571 { 1572 u->laddr = p->laddr; 1573 u->raddr = p->raddr; 1574 u->flags = p->flags; 1575 u->hop_limit = p->hop_limit; 1576 u->encap_limit = p->encap_limit; 1577 u->flowinfo = p->flowinfo; 1578 u->link = p->link; 1579 u->proto = p->proto; 1580 memcpy(u->name, p->name, sizeof(u->name)); 1581 } 1582 1583 /** 1584 * ip6_tnl_ioctl - configure ipv6 tunnels from userspace 1585 * @dev: virtual device associated with tunnel 1586 * @ifr: parameters passed from userspace 1587 * @cmd: command to be performed 1588 * 1589 * Description: 1590 * ip6_tnl_ioctl() is used for managing IPv6 tunnels 1591 * from userspace. 1592 * 1593 * The possible commands are the following: 1594 * %SIOCGETTUNNEL: get tunnel parameters for device 1595 * %SIOCADDTUNNEL: add tunnel matching given tunnel parameters 1596 * %SIOCCHGTUNNEL: change tunnel parameters to those given 1597 * %SIOCDELTUNNEL: delete tunnel 1598 * 1599 * The fallback device "ip6tnl0", created during module 1600 * initialization, can be used for creating other tunnel devices. 1601 * 1602 * Return: 1603 * 0 on success, 1604 * %-EFAULT if unable to copy data to or from userspace, 1605 * %-EPERM if current process hasn't %CAP_NET_ADMIN set 1606 * %-EINVAL if passed tunnel parameters are invalid, 1607 * %-EEXIST if changing a tunnel's parameters would cause a conflict 1608 * %-ENODEV if attempting to change or delete a nonexisting device 1609 **/ 1610 1611 static int 1612 ip6_tnl_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd) 1613 { 1614 int err = 0; 1615 struct ip6_tnl_parm p; 1616 struct __ip6_tnl_parm p1; 1617 struct ip6_tnl *t = netdev_priv(dev); 1618 struct net *net = t->net; 1619 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1620 1621 memset(&p1, 0, sizeof(p1)); 1622 1623 switch (cmd) { 1624 case SIOCGETTUNNEL: 1625 if (dev == ip6n->fb_tnl_dev) { 1626 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) { 1627 err = -EFAULT; 1628 break; 1629 } 1630 ip6_tnl_parm_from_user(&p1, &p); 1631 t = ip6_tnl_locate(net, &p1, 0); 1632 if (IS_ERR(t)) 1633 t = netdev_priv(dev); 1634 } else { 1635 memset(&p, 0, sizeof(p)); 1636 } 1637 ip6_tnl_parm_to_user(&p, &t->parms); 1638 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) { 1639 err = -EFAULT; 1640 } 1641 break; 1642 case SIOCADDTUNNEL: 1643 case SIOCCHGTUNNEL: 1644 err = -EPERM; 1645 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 1646 break; 1647 err = -EFAULT; 1648 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 1649 break; 1650 err = -EINVAL; 1651 if (p.proto != IPPROTO_IPV6 && p.proto != IPPROTO_IPIP && 1652 p.proto != 0) 1653 break; 1654 ip6_tnl_parm_from_user(&p1, &p); 1655 t = ip6_tnl_locate(net, &p1, cmd == SIOCADDTUNNEL); 1656 if (cmd == SIOCCHGTUNNEL) { 1657 if (!IS_ERR(t)) { 1658 if (t->dev != dev) { 1659 err = -EEXIST; 1660 break; 1661 } 1662 } else 1663 t = netdev_priv(dev); 1664 if (dev == ip6n->fb_tnl_dev) 1665 err = ip6_tnl0_update(t, &p1); 1666 else 1667 err = ip6_tnl_update(t, &p1); 1668 } 1669 if (!IS_ERR(t)) { 1670 err = 0; 1671 ip6_tnl_parm_to_user(&p, &t->parms); 1672 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) 1673 err = -EFAULT; 1674 1675 } else { 1676 err = PTR_ERR(t); 1677 } 1678 break; 1679 case SIOCDELTUNNEL: 1680 err = -EPERM; 1681 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 1682 break; 1683 1684 if (dev == ip6n->fb_tnl_dev) { 1685 err = -EFAULT; 1686 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 1687 break; 1688 err = -ENOENT; 1689 ip6_tnl_parm_from_user(&p1, &p); 1690 t = ip6_tnl_locate(net, &p1, 0); 1691 if (IS_ERR(t)) 1692 break; 1693 err = -EPERM; 1694 if (t->dev == ip6n->fb_tnl_dev) 1695 break; 1696 dev = t->dev; 1697 } 1698 err = 0; 1699 unregister_netdevice(dev); 1700 break; 1701 default: 1702 err = -EINVAL; 1703 } 1704 return err; 1705 } 1706 1707 /** 1708 * ip6_tnl_change_mtu - change mtu manually for tunnel device 1709 * @dev: virtual device associated with tunnel 1710 * @new_mtu: the new mtu 1711 * 1712 * Return: 1713 * 0 on success, 1714 * %-EINVAL if mtu too small 1715 **/ 1716 1717 int ip6_tnl_change_mtu(struct net_device *dev, int new_mtu) 1718 { 1719 struct ip6_tnl *tnl = netdev_priv(dev); 1720 1721 if (tnl->parms.proto == IPPROTO_IPV6) { 1722 if (new_mtu < IPV6_MIN_MTU) 1723 return -EINVAL; 1724 } else { 1725 if (new_mtu < ETH_MIN_MTU) 1726 return -EINVAL; 1727 } 1728 if (tnl->parms.proto == IPPROTO_IPV6 || tnl->parms.proto == 0) { 1729 if (new_mtu > IP6_MAX_MTU - dev->hard_header_len) 1730 return -EINVAL; 1731 } else { 1732 if (new_mtu > IP_MAX_MTU - dev->hard_header_len) 1733 return -EINVAL; 1734 } 1735 dev->mtu = new_mtu; 1736 return 0; 1737 } 1738 EXPORT_SYMBOL(ip6_tnl_change_mtu); 1739 1740 int ip6_tnl_get_iflink(const struct net_device *dev) 1741 { 1742 struct ip6_tnl *t = netdev_priv(dev); 1743 1744 return t->parms.link; 1745 } 1746 EXPORT_SYMBOL(ip6_tnl_get_iflink); 1747 1748 int ip6_tnl_encap_add_ops(const struct ip6_tnl_encap_ops *ops, 1749 unsigned int num) 1750 { 1751 if (num >= MAX_IPTUN_ENCAP_OPS) 1752 return -ERANGE; 1753 1754 return !cmpxchg((const struct ip6_tnl_encap_ops **) 1755 &ip6tun_encaps[num], 1756 NULL, ops) ? 0 : -1; 1757 } 1758 EXPORT_SYMBOL(ip6_tnl_encap_add_ops); 1759 1760 int ip6_tnl_encap_del_ops(const struct ip6_tnl_encap_ops *ops, 1761 unsigned int num) 1762 { 1763 int ret; 1764 1765 if (num >= MAX_IPTUN_ENCAP_OPS) 1766 return -ERANGE; 1767 1768 ret = (cmpxchg((const struct ip6_tnl_encap_ops **) 1769 &ip6tun_encaps[num], 1770 ops, NULL) == ops) ? 0 : -1; 1771 1772 synchronize_net(); 1773 1774 return ret; 1775 } 1776 EXPORT_SYMBOL(ip6_tnl_encap_del_ops); 1777 1778 int ip6_tnl_encap_setup(struct ip6_tnl *t, 1779 struct ip_tunnel_encap *ipencap) 1780 { 1781 int hlen; 1782 1783 memset(&t->encap, 0, sizeof(t->encap)); 1784 1785 hlen = ip6_encap_hlen(ipencap); 1786 if (hlen < 0) 1787 return hlen; 1788 1789 t->encap.type = ipencap->type; 1790 t->encap.sport = ipencap->sport; 1791 t->encap.dport = ipencap->dport; 1792 t->encap.flags = ipencap->flags; 1793 1794 t->encap_hlen = hlen; 1795 t->hlen = t->encap_hlen + t->tun_hlen; 1796 1797 return 0; 1798 } 1799 EXPORT_SYMBOL_GPL(ip6_tnl_encap_setup); 1800 1801 static const struct net_device_ops ip6_tnl_netdev_ops = { 1802 .ndo_init = ip6_tnl_dev_init, 1803 .ndo_uninit = ip6_tnl_dev_uninit, 1804 .ndo_start_xmit = ip6_tnl_start_xmit, 1805 .ndo_do_ioctl = ip6_tnl_ioctl, 1806 .ndo_change_mtu = ip6_tnl_change_mtu, 1807 .ndo_get_stats64 = dev_get_tstats64, 1808 .ndo_get_iflink = ip6_tnl_get_iflink, 1809 }; 1810 1811 #define IPXIPX_FEATURES (NETIF_F_SG | \ 1812 NETIF_F_FRAGLIST | \ 1813 NETIF_F_HIGHDMA | \ 1814 NETIF_F_GSO_SOFTWARE | \ 1815 NETIF_F_HW_CSUM) 1816 1817 /** 1818 * ip6_tnl_dev_setup - setup virtual tunnel device 1819 * @dev: virtual device associated with tunnel 1820 * 1821 * Description: 1822 * Initialize function pointers and device parameters 1823 **/ 1824 1825 static void ip6_tnl_dev_setup(struct net_device *dev) 1826 { 1827 dev->netdev_ops = &ip6_tnl_netdev_ops; 1828 dev->header_ops = &ip_tunnel_header_ops; 1829 dev->needs_free_netdev = true; 1830 dev->priv_destructor = ip6_dev_free; 1831 1832 dev->type = ARPHRD_TUNNEL6; 1833 dev->flags |= IFF_NOARP; 1834 dev->addr_len = sizeof(struct in6_addr); 1835 dev->features |= NETIF_F_LLTX; 1836 netif_keep_dst(dev); 1837 1838 dev->features |= IPXIPX_FEATURES; 1839 dev->hw_features |= IPXIPX_FEATURES; 1840 1841 /* This perm addr will be used as interface identifier by IPv6 */ 1842 dev->addr_assign_type = NET_ADDR_RANDOM; 1843 eth_random_addr(dev->perm_addr); 1844 } 1845 1846 1847 /** 1848 * ip6_tnl_dev_init_gen - general initializer for all tunnel devices 1849 * @dev: virtual device associated with tunnel 1850 **/ 1851 1852 static inline int 1853 ip6_tnl_dev_init_gen(struct net_device *dev) 1854 { 1855 struct ip6_tnl *t = netdev_priv(dev); 1856 int ret; 1857 int t_hlen; 1858 1859 t->dev = dev; 1860 t->net = dev_net(dev); 1861 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats); 1862 if (!dev->tstats) 1863 return -ENOMEM; 1864 1865 ret = dst_cache_init(&t->dst_cache, GFP_KERNEL); 1866 if (ret) 1867 goto free_stats; 1868 1869 ret = gro_cells_init(&t->gro_cells, dev); 1870 if (ret) 1871 goto destroy_dst; 1872 1873 t->tun_hlen = 0; 1874 t->hlen = t->encap_hlen + t->tun_hlen; 1875 t_hlen = t->hlen + sizeof(struct ipv6hdr); 1876 1877 dev->type = ARPHRD_TUNNEL6; 1878 dev->hard_header_len = LL_MAX_HEADER + t_hlen; 1879 dev->mtu = ETH_DATA_LEN - t_hlen; 1880 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1881 dev->mtu -= 8; 1882 dev->min_mtu = ETH_MIN_MTU; 1883 dev->max_mtu = IP6_MAX_MTU - dev->hard_header_len; 1884 1885 return 0; 1886 1887 destroy_dst: 1888 dst_cache_destroy(&t->dst_cache); 1889 free_stats: 1890 free_percpu(dev->tstats); 1891 dev->tstats = NULL; 1892 1893 return ret; 1894 } 1895 1896 /** 1897 * ip6_tnl_dev_init - initializer for all non fallback tunnel devices 1898 * @dev: virtual device associated with tunnel 1899 **/ 1900 1901 static int ip6_tnl_dev_init(struct net_device *dev) 1902 { 1903 struct ip6_tnl *t = netdev_priv(dev); 1904 int err = ip6_tnl_dev_init_gen(dev); 1905 1906 if (err) 1907 return err; 1908 ip6_tnl_link_config(t); 1909 if (t->parms.collect_md) 1910 netif_keep_dst(dev); 1911 return 0; 1912 } 1913 1914 /** 1915 * ip6_fb_tnl_dev_init - initializer for fallback tunnel device 1916 * @dev: fallback device 1917 * 1918 * Return: 0 1919 **/ 1920 1921 static int __net_init ip6_fb_tnl_dev_init(struct net_device *dev) 1922 { 1923 struct ip6_tnl *t = netdev_priv(dev); 1924 struct net *net = dev_net(dev); 1925 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1926 1927 t->parms.proto = IPPROTO_IPV6; 1928 dev_hold(dev); 1929 1930 rcu_assign_pointer(ip6n->tnls_wc[0], t); 1931 return 0; 1932 } 1933 1934 static int ip6_tnl_validate(struct nlattr *tb[], struct nlattr *data[], 1935 struct netlink_ext_ack *extack) 1936 { 1937 u8 proto; 1938 1939 if (!data || !data[IFLA_IPTUN_PROTO]) 1940 return 0; 1941 1942 proto = nla_get_u8(data[IFLA_IPTUN_PROTO]); 1943 if (proto != IPPROTO_IPV6 && 1944 proto != IPPROTO_IPIP && 1945 proto != 0) 1946 return -EINVAL; 1947 1948 return 0; 1949 } 1950 1951 static void ip6_tnl_netlink_parms(struct nlattr *data[], 1952 struct __ip6_tnl_parm *parms) 1953 { 1954 memset(parms, 0, sizeof(*parms)); 1955 1956 if (!data) 1957 return; 1958 1959 if (data[IFLA_IPTUN_LINK]) 1960 parms->link = nla_get_u32(data[IFLA_IPTUN_LINK]); 1961 1962 if (data[IFLA_IPTUN_LOCAL]) 1963 parms->laddr = nla_get_in6_addr(data[IFLA_IPTUN_LOCAL]); 1964 1965 if (data[IFLA_IPTUN_REMOTE]) 1966 parms->raddr = nla_get_in6_addr(data[IFLA_IPTUN_REMOTE]); 1967 1968 if (data[IFLA_IPTUN_TTL]) 1969 parms->hop_limit = nla_get_u8(data[IFLA_IPTUN_TTL]); 1970 1971 if (data[IFLA_IPTUN_ENCAP_LIMIT]) 1972 parms->encap_limit = nla_get_u8(data[IFLA_IPTUN_ENCAP_LIMIT]); 1973 1974 if (data[IFLA_IPTUN_FLOWINFO]) 1975 parms->flowinfo = nla_get_be32(data[IFLA_IPTUN_FLOWINFO]); 1976 1977 if (data[IFLA_IPTUN_FLAGS]) 1978 parms->flags = nla_get_u32(data[IFLA_IPTUN_FLAGS]); 1979 1980 if (data[IFLA_IPTUN_PROTO]) 1981 parms->proto = nla_get_u8(data[IFLA_IPTUN_PROTO]); 1982 1983 if (data[IFLA_IPTUN_COLLECT_METADATA]) 1984 parms->collect_md = true; 1985 1986 if (data[IFLA_IPTUN_FWMARK]) 1987 parms->fwmark = nla_get_u32(data[IFLA_IPTUN_FWMARK]); 1988 } 1989 1990 static bool ip6_tnl_netlink_encap_parms(struct nlattr *data[], 1991 struct ip_tunnel_encap *ipencap) 1992 { 1993 bool ret = false; 1994 1995 memset(ipencap, 0, sizeof(*ipencap)); 1996 1997 if (!data) 1998 return ret; 1999 2000 if (data[IFLA_IPTUN_ENCAP_TYPE]) { 2001 ret = true; 2002 ipencap->type = nla_get_u16(data[IFLA_IPTUN_ENCAP_TYPE]); 2003 } 2004 2005 if (data[IFLA_IPTUN_ENCAP_FLAGS]) { 2006 ret = true; 2007 ipencap->flags = nla_get_u16(data[IFLA_IPTUN_ENCAP_FLAGS]); 2008 } 2009 2010 if (data[IFLA_IPTUN_ENCAP_SPORT]) { 2011 ret = true; 2012 ipencap->sport = nla_get_be16(data[IFLA_IPTUN_ENCAP_SPORT]); 2013 } 2014 2015 if (data[IFLA_IPTUN_ENCAP_DPORT]) { 2016 ret = true; 2017 ipencap->dport = nla_get_be16(data[IFLA_IPTUN_ENCAP_DPORT]); 2018 } 2019 2020 return ret; 2021 } 2022 2023 static int ip6_tnl_newlink(struct net *src_net, struct net_device *dev, 2024 struct nlattr *tb[], struct nlattr *data[], 2025 struct netlink_ext_ack *extack) 2026 { 2027 struct net *net = dev_net(dev); 2028 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 2029 struct ip_tunnel_encap ipencap; 2030 struct ip6_tnl *nt, *t; 2031 int err; 2032 2033 nt = netdev_priv(dev); 2034 2035 if (ip6_tnl_netlink_encap_parms(data, &ipencap)) { 2036 err = ip6_tnl_encap_setup(nt, &ipencap); 2037 if (err < 0) 2038 return err; 2039 } 2040 2041 ip6_tnl_netlink_parms(data, &nt->parms); 2042 2043 if (nt->parms.collect_md) { 2044 if (rtnl_dereference(ip6n->collect_md_tun)) 2045 return -EEXIST; 2046 } else { 2047 t = ip6_tnl_locate(net, &nt->parms, 0); 2048 if (!IS_ERR(t)) 2049 return -EEXIST; 2050 } 2051 2052 err = ip6_tnl_create2(dev); 2053 if (!err && tb[IFLA_MTU]) 2054 ip6_tnl_change_mtu(dev, nla_get_u32(tb[IFLA_MTU])); 2055 2056 return err; 2057 } 2058 2059 static int ip6_tnl_changelink(struct net_device *dev, struct nlattr *tb[], 2060 struct nlattr *data[], 2061 struct netlink_ext_ack *extack) 2062 { 2063 struct ip6_tnl *t = netdev_priv(dev); 2064 struct __ip6_tnl_parm p; 2065 struct net *net = t->net; 2066 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 2067 struct ip_tunnel_encap ipencap; 2068 2069 if (dev == ip6n->fb_tnl_dev) 2070 return -EINVAL; 2071 2072 if (ip6_tnl_netlink_encap_parms(data, &ipencap)) { 2073 int err = ip6_tnl_encap_setup(t, &ipencap); 2074 2075 if (err < 0) 2076 return err; 2077 } 2078 ip6_tnl_netlink_parms(data, &p); 2079 if (p.collect_md) 2080 return -EINVAL; 2081 2082 t = ip6_tnl_locate(net, &p, 0); 2083 if (!IS_ERR(t)) { 2084 if (t->dev != dev) 2085 return -EEXIST; 2086 } else 2087 t = netdev_priv(dev); 2088 2089 return ip6_tnl_update(t, &p); 2090 } 2091 2092 static void ip6_tnl_dellink(struct net_device *dev, struct list_head *head) 2093 { 2094 struct net *net = dev_net(dev); 2095 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 2096 2097 if (dev != ip6n->fb_tnl_dev) 2098 unregister_netdevice_queue(dev, head); 2099 } 2100 2101 static size_t ip6_tnl_get_size(const struct net_device *dev) 2102 { 2103 return 2104 /* IFLA_IPTUN_LINK */ 2105 nla_total_size(4) + 2106 /* IFLA_IPTUN_LOCAL */ 2107 nla_total_size(sizeof(struct in6_addr)) + 2108 /* IFLA_IPTUN_REMOTE */ 2109 nla_total_size(sizeof(struct in6_addr)) + 2110 /* IFLA_IPTUN_TTL */ 2111 nla_total_size(1) + 2112 /* IFLA_IPTUN_ENCAP_LIMIT */ 2113 nla_total_size(1) + 2114 /* IFLA_IPTUN_FLOWINFO */ 2115 nla_total_size(4) + 2116 /* IFLA_IPTUN_FLAGS */ 2117 nla_total_size(4) + 2118 /* IFLA_IPTUN_PROTO */ 2119 nla_total_size(1) + 2120 /* IFLA_IPTUN_ENCAP_TYPE */ 2121 nla_total_size(2) + 2122 /* IFLA_IPTUN_ENCAP_FLAGS */ 2123 nla_total_size(2) + 2124 /* IFLA_IPTUN_ENCAP_SPORT */ 2125 nla_total_size(2) + 2126 /* IFLA_IPTUN_ENCAP_DPORT */ 2127 nla_total_size(2) + 2128 /* IFLA_IPTUN_COLLECT_METADATA */ 2129 nla_total_size(0) + 2130 /* IFLA_IPTUN_FWMARK */ 2131 nla_total_size(4) + 2132 0; 2133 } 2134 2135 static int ip6_tnl_fill_info(struct sk_buff *skb, const struct net_device *dev) 2136 { 2137 struct ip6_tnl *tunnel = netdev_priv(dev); 2138 struct __ip6_tnl_parm *parm = &tunnel->parms; 2139 2140 if (nla_put_u32(skb, IFLA_IPTUN_LINK, parm->link) || 2141 nla_put_in6_addr(skb, IFLA_IPTUN_LOCAL, &parm->laddr) || 2142 nla_put_in6_addr(skb, IFLA_IPTUN_REMOTE, &parm->raddr) || 2143 nla_put_u8(skb, IFLA_IPTUN_TTL, parm->hop_limit) || 2144 nla_put_u8(skb, IFLA_IPTUN_ENCAP_LIMIT, parm->encap_limit) || 2145 nla_put_be32(skb, IFLA_IPTUN_FLOWINFO, parm->flowinfo) || 2146 nla_put_u32(skb, IFLA_IPTUN_FLAGS, parm->flags) || 2147 nla_put_u8(skb, IFLA_IPTUN_PROTO, parm->proto) || 2148 nla_put_u32(skb, IFLA_IPTUN_FWMARK, parm->fwmark)) 2149 goto nla_put_failure; 2150 2151 if (nla_put_u16(skb, IFLA_IPTUN_ENCAP_TYPE, tunnel->encap.type) || 2152 nla_put_be16(skb, IFLA_IPTUN_ENCAP_SPORT, tunnel->encap.sport) || 2153 nla_put_be16(skb, IFLA_IPTUN_ENCAP_DPORT, tunnel->encap.dport) || 2154 nla_put_u16(skb, IFLA_IPTUN_ENCAP_FLAGS, tunnel->encap.flags)) 2155 goto nla_put_failure; 2156 2157 if (parm->collect_md) 2158 if (nla_put_flag(skb, IFLA_IPTUN_COLLECT_METADATA)) 2159 goto nla_put_failure; 2160 2161 return 0; 2162 2163 nla_put_failure: 2164 return -EMSGSIZE; 2165 } 2166 2167 struct net *ip6_tnl_get_link_net(const struct net_device *dev) 2168 { 2169 struct ip6_tnl *tunnel = netdev_priv(dev); 2170 2171 return tunnel->net; 2172 } 2173 EXPORT_SYMBOL(ip6_tnl_get_link_net); 2174 2175 static const struct nla_policy ip6_tnl_policy[IFLA_IPTUN_MAX + 1] = { 2176 [IFLA_IPTUN_LINK] = { .type = NLA_U32 }, 2177 [IFLA_IPTUN_LOCAL] = { .len = sizeof(struct in6_addr) }, 2178 [IFLA_IPTUN_REMOTE] = { .len = sizeof(struct in6_addr) }, 2179 [IFLA_IPTUN_TTL] = { .type = NLA_U8 }, 2180 [IFLA_IPTUN_ENCAP_LIMIT] = { .type = NLA_U8 }, 2181 [IFLA_IPTUN_FLOWINFO] = { .type = NLA_U32 }, 2182 [IFLA_IPTUN_FLAGS] = { .type = NLA_U32 }, 2183 [IFLA_IPTUN_PROTO] = { .type = NLA_U8 }, 2184 [IFLA_IPTUN_ENCAP_TYPE] = { .type = NLA_U16 }, 2185 [IFLA_IPTUN_ENCAP_FLAGS] = { .type = NLA_U16 }, 2186 [IFLA_IPTUN_ENCAP_SPORT] = { .type = NLA_U16 }, 2187 [IFLA_IPTUN_ENCAP_DPORT] = { .type = NLA_U16 }, 2188 [IFLA_IPTUN_COLLECT_METADATA] = { .type = NLA_FLAG }, 2189 [IFLA_IPTUN_FWMARK] = { .type = NLA_U32 }, 2190 }; 2191 2192 static struct rtnl_link_ops ip6_link_ops __read_mostly = { 2193 .kind = "ip6tnl", 2194 .maxtype = IFLA_IPTUN_MAX, 2195 .policy = ip6_tnl_policy, 2196 .priv_size = sizeof(struct ip6_tnl), 2197 .setup = ip6_tnl_dev_setup, 2198 .validate = ip6_tnl_validate, 2199 .newlink = ip6_tnl_newlink, 2200 .changelink = ip6_tnl_changelink, 2201 .dellink = ip6_tnl_dellink, 2202 .get_size = ip6_tnl_get_size, 2203 .fill_info = ip6_tnl_fill_info, 2204 .get_link_net = ip6_tnl_get_link_net, 2205 }; 2206 2207 static struct xfrm6_tunnel ip4ip6_handler __read_mostly = { 2208 .handler = ip4ip6_rcv, 2209 .err_handler = ip4ip6_err, 2210 .priority = 1, 2211 }; 2212 2213 static struct xfrm6_tunnel ip6ip6_handler __read_mostly = { 2214 .handler = ip6ip6_rcv, 2215 .err_handler = ip6ip6_err, 2216 .priority = 1, 2217 }; 2218 2219 static struct xfrm6_tunnel mplsip6_handler __read_mostly = { 2220 .handler = mplsip6_rcv, 2221 .err_handler = mplsip6_err, 2222 .priority = 1, 2223 }; 2224 2225 static void __net_exit ip6_tnl_destroy_tunnels(struct net *net, struct list_head *list) 2226 { 2227 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 2228 struct net_device *dev, *aux; 2229 int h; 2230 struct ip6_tnl *t; 2231 2232 for_each_netdev_safe(net, dev, aux) 2233 if (dev->rtnl_link_ops == &ip6_link_ops) 2234 unregister_netdevice_queue(dev, list); 2235 2236 for (h = 0; h < IP6_TUNNEL_HASH_SIZE; h++) { 2237 t = rtnl_dereference(ip6n->tnls_r_l[h]); 2238 while (t) { 2239 /* If dev is in the same netns, it has already 2240 * been added to the list by the previous loop. 2241 */ 2242 if (!net_eq(dev_net(t->dev), net)) 2243 unregister_netdevice_queue(t->dev, list); 2244 t = rtnl_dereference(t->next); 2245 } 2246 } 2247 } 2248 2249 static int __net_init ip6_tnl_init_net(struct net *net) 2250 { 2251 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 2252 struct ip6_tnl *t = NULL; 2253 int err; 2254 2255 ip6n->tnls[0] = ip6n->tnls_wc; 2256 ip6n->tnls[1] = ip6n->tnls_r_l; 2257 2258 if (!net_has_fallback_tunnels(net)) 2259 return 0; 2260 err = -ENOMEM; 2261 ip6n->fb_tnl_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6tnl0", 2262 NET_NAME_UNKNOWN, ip6_tnl_dev_setup); 2263 2264 if (!ip6n->fb_tnl_dev) 2265 goto err_alloc_dev; 2266 dev_net_set(ip6n->fb_tnl_dev, net); 2267 ip6n->fb_tnl_dev->rtnl_link_ops = &ip6_link_ops; 2268 /* FB netdevice is special: we have one, and only one per netns. 2269 * Allowing to move it to another netns is clearly unsafe. 2270 */ 2271 ip6n->fb_tnl_dev->features |= NETIF_F_NETNS_LOCAL; 2272 2273 err = ip6_fb_tnl_dev_init(ip6n->fb_tnl_dev); 2274 if (err < 0) 2275 goto err_register; 2276 2277 err = register_netdev(ip6n->fb_tnl_dev); 2278 if (err < 0) 2279 goto err_register; 2280 2281 t = netdev_priv(ip6n->fb_tnl_dev); 2282 2283 strcpy(t->parms.name, ip6n->fb_tnl_dev->name); 2284 return 0; 2285 2286 err_register: 2287 free_netdev(ip6n->fb_tnl_dev); 2288 err_alloc_dev: 2289 return err; 2290 } 2291 2292 static void __net_exit ip6_tnl_exit_batch_net(struct list_head *net_list) 2293 { 2294 struct net *net; 2295 LIST_HEAD(list); 2296 2297 rtnl_lock(); 2298 list_for_each_entry(net, net_list, exit_list) 2299 ip6_tnl_destroy_tunnels(net, &list); 2300 unregister_netdevice_many(&list); 2301 rtnl_unlock(); 2302 } 2303 2304 static struct pernet_operations ip6_tnl_net_ops = { 2305 .init = ip6_tnl_init_net, 2306 .exit_batch = ip6_tnl_exit_batch_net, 2307 .id = &ip6_tnl_net_id, 2308 .size = sizeof(struct ip6_tnl_net), 2309 }; 2310 2311 /** 2312 * ip6_tunnel_init - register protocol and reserve needed resources 2313 * 2314 * Return: 0 on success 2315 **/ 2316 2317 static int __init ip6_tunnel_init(void) 2318 { 2319 int err; 2320 2321 if (!ipv6_mod_enabled()) 2322 return -EOPNOTSUPP; 2323 2324 err = register_pernet_device(&ip6_tnl_net_ops); 2325 if (err < 0) 2326 goto out_pernet; 2327 2328 err = xfrm6_tunnel_register(&ip4ip6_handler, AF_INET); 2329 if (err < 0) { 2330 pr_err("%s: can't register ip4ip6\n", __func__); 2331 goto out_ip4ip6; 2332 } 2333 2334 err = xfrm6_tunnel_register(&ip6ip6_handler, AF_INET6); 2335 if (err < 0) { 2336 pr_err("%s: can't register ip6ip6\n", __func__); 2337 goto out_ip6ip6; 2338 } 2339 2340 if (ip6_tnl_mpls_supported()) { 2341 err = xfrm6_tunnel_register(&mplsip6_handler, AF_MPLS); 2342 if (err < 0) { 2343 pr_err("%s: can't register mplsip6\n", __func__); 2344 goto out_mplsip6; 2345 } 2346 } 2347 2348 err = rtnl_link_register(&ip6_link_ops); 2349 if (err < 0) 2350 goto rtnl_link_failed; 2351 2352 return 0; 2353 2354 rtnl_link_failed: 2355 if (ip6_tnl_mpls_supported()) 2356 xfrm6_tunnel_deregister(&mplsip6_handler, AF_MPLS); 2357 out_mplsip6: 2358 xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6); 2359 out_ip6ip6: 2360 xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET); 2361 out_ip4ip6: 2362 unregister_pernet_device(&ip6_tnl_net_ops); 2363 out_pernet: 2364 return err; 2365 } 2366 2367 /** 2368 * ip6_tunnel_cleanup - free resources and unregister protocol 2369 **/ 2370 2371 static void __exit ip6_tunnel_cleanup(void) 2372 { 2373 rtnl_link_unregister(&ip6_link_ops); 2374 if (xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET)) 2375 pr_info("%s: can't deregister ip4ip6\n", __func__); 2376 2377 if (xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6)) 2378 pr_info("%s: can't deregister ip6ip6\n", __func__); 2379 2380 if (ip6_tnl_mpls_supported() && 2381 xfrm6_tunnel_deregister(&mplsip6_handler, AF_MPLS)) 2382 pr_info("%s: can't deregister mplsip6\n", __func__); 2383 unregister_pernet_device(&ip6_tnl_net_ops); 2384 } 2385 2386 module_init(ip6_tunnel_init); 2387 module_exit(ip6_tunnel_cleanup); 2388