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 } 251 252 static int ip6_tnl_create2(struct net_device *dev) 253 { 254 struct ip6_tnl *t = netdev_priv(dev); 255 struct net *net = dev_net(dev); 256 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 257 int err; 258 259 dev->rtnl_link_ops = &ip6_link_ops; 260 err = register_netdevice(dev); 261 if (err < 0) 262 goto out; 263 264 strcpy(t->parms.name, dev->name); 265 266 ip6_tnl_link(ip6n, t); 267 return 0; 268 269 out: 270 return err; 271 } 272 273 /** 274 * ip6_tnl_create - create a new tunnel 275 * @net: network namespace 276 * @p: tunnel parameters 277 * 278 * Description: 279 * Create tunnel matching given parameters. 280 * 281 * Return: 282 * created tunnel or error pointer 283 **/ 284 285 static struct ip6_tnl *ip6_tnl_create(struct net *net, struct __ip6_tnl_parm *p) 286 { 287 struct net_device *dev; 288 struct ip6_tnl *t; 289 char name[IFNAMSIZ]; 290 int err = -E2BIG; 291 292 if (p->name[0]) { 293 if (!dev_valid_name(p->name)) 294 goto failed; 295 strscpy(name, p->name, IFNAMSIZ); 296 } else { 297 sprintf(name, "ip6tnl%%d"); 298 } 299 err = -ENOMEM; 300 dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN, 301 ip6_tnl_dev_setup); 302 if (!dev) 303 goto failed; 304 305 dev_net_set(dev, net); 306 307 t = netdev_priv(dev); 308 t->parms = *p; 309 t->net = dev_net(dev); 310 err = ip6_tnl_create2(dev); 311 if (err < 0) 312 goto failed_free; 313 314 return t; 315 316 failed_free: 317 free_netdev(dev); 318 failed: 319 return ERR_PTR(err); 320 } 321 322 /** 323 * ip6_tnl_locate - find or create tunnel matching given parameters 324 * @net: network namespace 325 * @p: tunnel parameters 326 * @create: != 0 if allowed to create new tunnel if no match found 327 * 328 * Description: 329 * ip6_tnl_locate() first tries to locate an existing tunnel 330 * based on @parms. If this is unsuccessful, but @create is set a new 331 * tunnel device is created and registered for use. 332 * 333 * Return: 334 * matching tunnel or error pointer 335 **/ 336 337 static struct ip6_tnl *ip6_tnl_locate(struct net *net, 338 struct __ip6_tnl_parm *p, int create) 339 { 340 const struct in6_addr *remote = &p->raddr; 341 const struct in6_addr *local = &p->laddr; 342 struct ip6_tnl __rcu **tp; 343 struct ip6_tnl *t; 344 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 345 346 for (tp = ip6_tnl_bucket(ip6n, p); 347 (t = rtnl_dereference(*tp)) != NULL; 348 tp = &t->next) { 349 if (ipv6_addr_equal(local, &t->parms.laddr) && 350 ipv6_addr_equal(remote, &t->parms.raddr) && 351 p->link == t->parms.link) { 352 if (create) 353 return ERR_PTR(-EEXIST); 354 355 return t; 356 } 357 } 358 if (!create) 359 return ERR_PTR(-ENODEV); 360 return ip6_tnl_create(net, p); 361 } 362 363 /** 364 * ip6_tnl_dev_uninit - tunnel device uninitializer 365 * @dev: the device to be destroyed 366 * 367 * Description: 368 * ip6_tnl_dev_uninit() removes tunnel from its list 369 **/ 370 371 static void 372 ip6_tnl_dev_uninit(struct net_device *dev) 373 { 374 struct ip6_tnl *t = netdev_priv(dev); 375 struct net *net = t->net; 376 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 377 378 if (dev == ip6n->fb_tnl_dev) 379 RCU_INIT_POINTER(ip6n->tnls_wc[0], NULL); 380 else 381 ip6_tnl_unlink(ip6n, t); 382 dst_cache_reset(&t->dst_cache); 383 netdev_put(dev, &t->dev_tracker); 384 } 385 386 /** 387 * ip6_tnl_parse_tlv_enc_lim - handle encapsulation limit option 388 * @skb: received socket buffer 389 * @raw: the ICMPv6 error message data 390 * 391 * Return: 392 * 0 if none was found, 393 * else index to encapsulation limit 394 **/ 395 396 __u16 ip6_tnl_parse_tlv_enc_lim(struct sk_buff *skb, __u8 *raw) 397 { 398 const struct ipv6hdr *ipv6h = (const struct ipv6hdr *)raw; 399 unsigned int nhoff = raw - skb->data; 400 unsigned int off = nhoff + sizeof(*ipv6h); 401 u8 nexthdr = ipv6h->nexthdr; 402 403 while (ipv6_ext_hdr(nexthdr) && nexthdr != NEXTHDR_NONE) { 404 struct ipv6_opt_hdr *hdr; 405 u16 optlen; 406 407 if (!pskb_may_pull(skb, off + sizeof(*hdr))) 408 break; 409 410 hdr = (struct ipv6_opt_hdr *)(skb->data + off); 411 if (nexthdr == NEXTHDR_FRAGMENT) { 412 optlen = 8; 413 } else if (nexthdr == NEXTHDR_AUTH) { 414 optlen = ipv6_authlen(hdr); 415 } else { 416 optlen = ipv6_optlen(hdr); 417 } 418 419 if (!pskb_may_pull(skb, off + optlen)) 420 break; 421 422 hdr = (struct ipv6_opt_hdr *)(skb->data + off); 423 if (nexthdr == NEXTHDR_FRAGMENT) { 424 struct frag_hdr *frag_hdr = (struct frag_hdr *)hdr; 425 426 if (frag_hdr->frag_off) 427 break; 428 } 429 if (nexthdr == NEXTHDR_DEST) { 430 u16 i = 2; 431 432 while (1) { 433 struct ipv6_tlv_tnl_enc_lim *tel; 434 435 /* No more room for encapsulation limit */ 436 if (i + sizeof(*tel) > optlen) 437 break; 438 439 tel = (struct ipv6_tlv_tnl_enc_lim *)(skb->data + off + i); 440 /* return index of option if found and valid */ 441 if (tel->type == IPV6_TLV_TNL_ENCAP_LIMIT && 442 tel->length == 1) 443 return i + off - nhoff; 444 /* else jump to next option */ 445 if (tel->type) 446 i += tel->length + 2; 447 else 448 i++; 449 } 450 } 451 nexthdr = hdr->nexthdr; 452 off += optlen; 453 } 454 return 0; 455 } 456 EXPORT_SYMBOL(ip6_tnl_parse_tlv_enc_lim); 457 458 /* ip6_tnl_err() should handle errors in the tunnel according to the 459 * specifications in RFC 2473. 460 */ 461 static int 462 ip6_tnl_err(struct sk_buff *skb, __u8 ipproto, struct inet6_skb_parm *opt, 463 u8 *type, u8 *code, int *msg, __u32 *info, int offset) 464 { 465 const struct ipv6hdr *ipv6h = (const struct ipv6hdr *)skb->data; 466 struct net *net = dev_net(skb->dev); 467 u8 rel_type = ICMPV6_DEST_UNREACH; 468 u8 rel_code = ICMPV6_ADDR_UNREACH; 469 __u32 rel_info = 0; 470 struct ip6_tnl *t; 471 int err = -ENOENT; 472 int rel_msg = 0; 473 u8 tproto; 474 __u16 len; 475 476 /* If the packet doesn't contain the original IPv6 header we are 477 in trouble since we might need the source address for further 478 processing of the error. */ 479 480 rcu_read_lock(); 481 t = ip6_tnl_lookup(dev_net(skb->dev), skb->dev->ifindex, &ipv6h->daddr, &ipv6h->saddr); 482 if (!t) 483 goto out; 484 485 tproto = READ_ONCE(t->parms.proto); 486 if (tproto != ipproto && tproto != 0) 487 goto out; 488 489 err = 0; 490 491 switch (*type) { 492 case ICMPV6_DEST_UNREACH: 493 net_dbg_ratelimited("%s: Path to destination invalid or inactive!\n", 494 t->parms.name); 495 rel_msg = 1; 496 break; 497 case ICMPV6_TIME_EXCEED: 498 if ((*code) == ICMPV6_EXC_HOPLIMIT) { 499 net_dbg_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n", 500 t->parms.name); 501 rel_msg = 1; 502 } 503 break; 504 case ICMPV6_PARAMPROB: { 505 struct ipv6_tlv_tnl_enc_lim *tel; 506 __u32 teli; 507 508 teli = 0; 509 if ((*code) == ICMPV6_HDR_FIELD) 510 teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data); 511 512 if (teli && teli == *info - 2) { 513 tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli]; 514 if (tel->encap_limit == 0) { 515 net_dbg_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n", 516 t->parms.name); 517 rel_msg = 1; 518 } 519 } else { 520 net_dbg_ratelimited("%s: Recipient unable to parse tunneled packet!\n", 521 t->parms.name); 522 } 523 break; 524 } 525 case ICMPV6_PKT_TOOBIG: { 526 __u32 mtu; 527 528 ip6_update_pmtu(skb, net, htonl(*info), 0, 0, 529 sock_net_uid(net, NULL)); 530 mtu = *info - offset; 531 if (mtu < IPV6_MIN_MTU) 532 mtu = IPV6_MIN_MTU; 533 len = sizeof(*ipv6h) + ntohs(ipv6h->payload_len); 534 if (len > mtu) { 535 rel_type = ICMPV6_PKT_TOOBIG; 536 rel_code = 0; 537 rel_info = mtu; 538 rel_msg = 1; 539 } 540 break; 541 } 542 case NDISC_REDIRECT: 543 ip6_redirect(skb, net, skb->dev->ifindex, 0, 544 sock_net_uid(net, NULL)); 545 break; 546 } 547 548 *type = rel_type; 549 *code = rel_code; 550 *info = rel_info; 551 *msg = rel_msg; 552 553 out: 554 rcu_read_unlock(); 555 return err; 556 } 557 558 static int 559 ip4ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 560 u8 type, u8 code, int offset, __be32 info) 561 { 562 __u32 rel_info = ntohl(info); 563 const struct iphdr *eiph; 564 struct sk_buff *skb2; 565 int err, rel_msg = 0; 566 u8 rel_type = type; 567 u8 rel_code = code; 568 struct rtable *rt; 569 struct flowi4 fl4; 570 571 err = ip6_tnl_err(skb, IPPROTO_IPIP, opt, &rel_type, &rel_code, 572 &rel_msg, &rel_info, offset); 573 if (err < 0) 574 return err; 575 576 if (rel_msg == 0) 577 return 0; 578 579 switch (rel_type) { 580 case ICMPV6_DEST_UNREACH: 581 if (rel_code != ICMPV6_ADDR_UNREACH) 582 return 0; 583 rel_type = ICMP_DEST_UNREACH; 584 rel_code = ICMP_HOST_UNREACH; 585 break; 586 case ICMPV6_PKT_TOOBIG: 587 if (rel_code != 0) 588 return 0; 589 rel_type = ICMP_DEST_UNREACH; 590 rel_code = ICMP_FRAG_NEEDED; 591 break; 592 default: 593 return 0; 594 } 595 596 if (!pskb_may_pull(skb, offset + sizeof(struct iphdr))) 597 return 0; 598 599 skb2 = skb_clone(skb, GFP_ATOMIC); 600 if (!skb2) 601 return 0; 602 603 skb_dst_drop(skb2); 604 605 skb_pull(skb2, offset); 606 skb_reset_network_header(skb2); 607 eiph = ip_hdr(skb2); 608 609 /* Try to guess incoming interface */ 610 rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL, eiph->saddr, 611 0, 0, 0, IPPROTO_IPIP, RT_TOS(eiph->tos), 0); 612 if (IS_ERR(rt)) 613 goto out; 614 615 skb2->dev = rt->dst.dev; 616 ip_rt_put(rt); 617 618 /* route "incoming" packet */ 619 if (rt->rt_flags & RTCF_LOCAL) { 620 rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL, 621 eiph->daddr, eiph->saddr, 0, 0, 622 IPPROTO_IPIP, RT_TOS(eiph->tos), 0); 623 if (IS_ERR(rt) || rt->dst.dev->type != ARPHRD_TUNNEL6) { 624 if (!IS_ERR(rt)) 625 ip_rt_put(rt); 626 goto out; 627 } 628 skb_dst_set(skb2, &rt->dst); 629 } else { 630 if (ip_route_input(skb2, eiph->daddr, eiph->saddr, eiph->tos, 631 skb2->dev) || 632 skb_dst(skb2)->dev->type != ARPHRD_TUNNEL6) 633 goto out; 634 } 635 636 /* change mtu on this route */ 637 if (rel_type == ICMP_DEST_UNREACH && rel_code == ICMP_FRAG_NEEDED) { 638 if (rel_info > dst_mtu(skb_dst(skb2))) 639 goto out; 640 641 skb_dst_update_pmtu_no_confirm(skb2, rel_info); 642 } 643 644 icmp_send(skb2, rel_type, rel_code, htonl(rel_info)); 645 646 out: 647 kfree_skb(skb2); 648 return 0; 649 } 650 651 static int 652 ip6ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 653 u8 type, u8 code, int offset, __be32 info) 654 { 655 __u32 rel_info = ntohl(info); 656 int err, rel_msg = 0; 657 u8 rel_type = type; 658 u8 rel_code = code; 659 660 err = ip6_tnl_err(skb, IPPROTO_IPV6, opt, &rel_type, &rel_code, 661 &rel_msg, &rel_info, offset); 662 if (err < 0) 663 return err; 664 665 if (rel_msg && pskb_may_pull(skb, offset + sizeof(struct ipv6hdr))) { 666 struct rt6_info *rt; 667 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC); 668 669 if (!skb2) 670 return 0; 671 672 skb_dst_drop(skb2); 673 skb_pull(skb2, offset); 674 skb_reset_network_header(skb2); 675 676 /* Try to guess incoming interface */ 677 rt = rt6_lookup(dev_net(skb->dev), &ipv6_hdr(skb2)->saddr, 678 NULL, 0, skb2, 0); 679 680 if (rt && rt->dst.dev) 681 skb2->dev = rt->dst.dev; 682 683 icmpv6_send(skb2, rel_type, rel_code, rel_info); 684 685 ip6_rt_put(rt); 686 687 kfree_skb(skb2); 688 } 689 690 return 0; 691 } 692 693 static int 694 mplsip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 695 u8 type, u8 code, int offset, __be32 info) 696 { 697 __u32 rel_info = ntohl(info); 698 int err, rel_msg = 0; 699 u8 rel_type = type; 700 u8 rel_code = code; 701 702 err = ip6_tnl_err(skb, IPPROTO_MPLS, opt, &rel_type, &rel_code, 703 &rel_msg, &rel_info, offset); 704 return err; 705 } 706 707 static int ip4ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t, 708 const struct ipv6hdr *ipv6h, 709 struct sk_buff *skb) 710 { 711 __u8 dsfield = ipv6_get_dsfield(ipv6h) & ~INET_ECN_MASK; 712 713 if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY) 714 ipv4_change_dsfield(ip_hdr(skb), INET_ECN_MASK, dsfield); 715 716 return IP6_ECN_decapsulate(ipv6h, skb); 717 } 718 719 static int ip6ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t, 720 const struct ipv6hdr *ipv6h, 721 struct sk_buff *skb) 722 { 723 if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY) 724 ipv6_copy_dscp(ipv6_get_dsfield(ipv6h), ipv6_hdr(skb)); 725 726 return IP6_ECN_decapsulate(ipv6h, skb); 727 } 728 729 static inline int mplsip6_dscp_ecn_decapsulate(const struct ip6_tnl *t, 730 const struct ipv6hdr *ipv6h, 731 struct sk_buff *skb) 732 { 733 /* ECN is not supported in AF_MPLS */ 734 return 0; 735 } 736 737 __u32 ip6_tnl_get_cap(struct ip6_tnl *t, 738 const struct in6_addr *laddr, 739 const struct in6_addr *raddr) 740 { 741 struct __ip6_tnl_parm *p = &t->parms; 742 int ltype = ipv6_addr_type(laddr); 743 int rtype = ipv6_addr_type(raddr); 744 __u32 flags = 0; 745 746 if (ltype == IPV6_ADDR_ANY || rtype == IPV6_ADDR_ANY) { 747 flags = IP6_TNL_F_CAP_PER_PACKET; 748 } else if (ltype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) && 749 rtype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) && 750 !((ltype|rtype) & IPV6_ADDR_LOOPBACK) && 751 (!((ltype|rtype) & IPV6_ADDR_LINKLOCAL) || p->link)) { 752 if (ltype&IPV6_ADDR_UNICAST) 753 flags |= IP6_TNL_F_CAP_XMIT; 754 if (rtype&IPV6_ADDR_UNICAST) 755 flags |= IP6_TNL_F_CAP_RCV; 756 } 757 return flags; 758 } 759 EXPORT_SYMBOL(ip6_tnl_get_cap); 760 761 /* called with rcu_read_lock() */ 762 int ip6_tnl_rcv_ctl(struct ip6_tnl *t, 763 const struct in6_addr *laddr, 764 const struct in6_addr *raddr) 765 { 766 struct __ip6_tnl_parm *p = &t->parms; 767 int ret = 0; 768 struct net *net = t->net; 769 770 if ((p->flags & IP6_TNL_F_CAP_RCV) || 771 ((p->flags & IP6_TNL_F_CAP_PER_PACKET) && 772 (ip6_tnl_get_cap(t, laddr, raddr) & IP6_TNL_F_CAP_RCV))) { 773 struct net_device *ldev = NULL; 774 775 if (p->link) 776 ldev = dev_get_by_index_rcu(net, p->link); 777 778 if ((ipv6_addr_is_multicast(laddr) || 779 likely(ipv6_chk_addr_and_flags(net, laddr, ldev, false, 780 0, IFA_F_TENTATIVE))) && 781 ((p->flags & IP6_TNL_F_ALLOW_LOCAL_REMOTE) || 782 likely(!ipv6_chk_addr_and_flags(net, raddr, ldev, true, 783 0, IFA_F_TENTATIVE)))) 784 ret = 1; 785 } 786 return ret; 787 } 788 EXPORT_SYMBOL_GPL(ip6_tnl_rcv_ctl); 789 790 static int __ip6_tnl_rcv(struct ip6_tnl *tunnel, struct sk_buff *skb, 791 const struct tnl_ptk_info *tpi, 792 struct metadata_dst *tun_dst, 793 int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t, 794 const struct ipv6hdr *ipv6h, 795 struct sk_buff *skb), 796 bool log_ecn_err) 797 { 798 const struct ipv6hdr *ipv6h; 799 int nh, err; 800 801 if (test_bit(IP_TUNNEL_CSUM_BIT, tunnel->parms.i_flags) != 802 test_bit(IP_TUNNEL_CSUM_BIT, tpi->flags)) { 803 DEV_STATS_INC(tunnel->dev, rx_crc_errors); 804 DEV_STATS_INC(tunnel->dev, rx_errors); 805 goto drop; 806 } 807 808 if (test_bit(IP_TUNNEL_SEQ_BIT, tunnel->parms.i_flags)) { 809 if (!test_bit(IP_TUNNEL_SEQ_BIT, tpi->flags) || 810 (tunnel->i_seqno && 811 (s32)(ntohl(tpi->seq) - tunnel->i_seqno) < 0)) { 812 DEV_STATS_INC(tunnel->dev, rx_fifo_errors); 813 DEV_STATS_INC(tunnel->dev, rx_errors); 814 goto drop; 815 } 816 tunnel->i_seqno = ntohl(tpi->seq) + 1; 817 } 818 819 skb->protocol = tpi->proto; 820 821 /* Warning: All skb pointers will be invalidated! */ 822 if (tunnel->dev->type == ARPHRD_ETHER) { 823 if (!pskb_may_pull(skb, ETH_HLEN)) { 824 DEV_STATS_INC(tunnel->dev, rx_length_errors); 825 DEV_STATS_INC(tunnel->dev, rx_errors); 826 goto drop; 827 } 828 829 skb->protocol = eth_type_trans(skb, tunnel->dev); 830 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN); 831 } else { 832 skb->dev = tunnel->dev; 833 skb_reset_mac_header(skb); 834 } 835 836 /* Save offset of outer header relative to skb->head, 837 * because we are going to reset the network header to the inner header 838 * and might change skb->head. 839 */ 840 nh = skb_network_header(skb) - skb->head; 841 842 skb_reset_network_header(skb); 843 844 if (!pskb_inet_may_pull(skb)) { 845 DEV_STATS_INC(tunnel->dev, rx_length_errors); 846 DEV_STATS_INC(tunnel->dev, rx_errors); 847 goto drop; 848 } 849 850 /* Get the outer header. */ 851 ipv6h = (struct ipv6hdr *)(skb->head + nh); 852 853 memset(skb->cb, 0, sizeof(struct inet6_skb_parm)); 854 855 __skb_tunnel_rx(skb, tunnel->dev, tunnel->net); 856 857 err = dscp_ecn_decapsulate(tunnel, ipv6h, skb); 858 if (unlikely(err)) { 859 if (log_ecn_err) 860 net_info_ratelimited("non-ECT from %pI6 with DS=%#x\n", 861 &ipv6h->saddr, 862 ipv6_get_dsfield(ipv6h)); 863 if (err > 1) { 864 DEV_STATS_INC(tunnel->dev, rx_frame_errors); 865 DEV_STATS_INC(tunnel->dev, rx_errors); 866 goto drop; 867 } 868 } 869 870 dev_sw_netstats_rx_add(tunnel->dev, skb->len); 871 872 skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(tunnel->dev))); 873 874 if (tun_dst) 875 skb_dst_set(skb, (struct dst_entry *)tun_dst); 876 877 gro_cells_receive(&tunnel->gro_cells, skb); 878 return 0; 879 880 drop: 881 if (tun_dst) 882 dst_release((struct dst_entry *)tun_dst); 883 kfree_skb(skb); 884 return 0; 885 } 886 887 int ip6_tnl_rcv(struct ip6_tnl *t, struct sk_buff *skb, 888 const struct tnl_ptk_info *tpi, 889 struct metadata_dst *tun_dst, 890 bool log_ecn_err) 891 { 892 int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t, 893 const struct ipv6hdr *ipv6h, 894 struct sk_buff *skb); 895 896 dscp_ecn_decapsulate = ip6ip6_dscp_ecn_decapsulate; 897 if (tpi->proto == htons(ETH_P_IP)) 898 dscp_ecn_decapsulate = ip4ip6_dscp_ecn_decapsulate; 899 900 return __ip6_tnl_rcv(t, skb, tpi, tun_dst, dscp_ecn_decapsulate, 901 log_ecn_err); 902 } 903 EXPORT_SYMBOL(ip6_tnl_rcv); 904 905 static const struct tnl_ptk_info tpi_v6 = { 906 /* no tunnel info required for ipxip6. */ 907 .proto = htons(ETH_P_IPV6), 908 }; 909 910 static const struct tnl_ptk_info tpi_v4 = { 911 /* no tunnel info required for ipxip6. */ 912 .proto = htons(ETH_P_IP), 913 }; 914 915 static const struct tnl_ptk_info tpi_mpls = { 916 /* no tunnel info required for mplsip6. */ 917 .proto = htons(ETH_P_MPLS_UC), 918 }; 919 920 static int ipxip6_rcv(struct sk_buff *skb, u8 ipproto, 921 const struct tnl_ptk_info *tpi, 922 int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t, 923 const struct ipv6hdr *ipv6h, 924 struct sk_buff *skb)) 925 { 926 struct ip6_tnl *t; 927 const struct ipv6hdr *ipv6h = ipv6_hdr(skb); 928 struct metadata_dst *tun_dst = NULL; 929 int ret = -1; 930 931 rcu_read_lock(); 932 t = ip6_tnl_lookup(dev_net(skb->dev), skb->dev->ifindex, &ipv6h->saddr, &ipv6h->daddr); 933 934 if (t) { 935 u8 tproto = READ_ONCE(t->parms.proto); 936 937 if (tproto != ipproto && tproto != 0) 938 goto drop; 939 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) 940 goto drop; 941 ipv6h = ipv6_hdr(skb); 942 if (!ip6_tnl_rcv_ctl(t, &ipv6h->daddr, &ipv6h->saddr)) 943 goto drop; 944 if (iptunnel_pull_header(skb, 0, tpi->proto, false)) 945 goto drop; 946 if (t->parms.collect_md) { 947 IP_TUNNEL_DECLARE_FLAGS(flags) = { }; 948 949 tun_dst = ipv6_tun_rx_dst(skb, flags, 0, 0); 950 if (!tun_dst) 951 goto drop; 952 } 953 ret = __ip6_tnl_rcv(t, skb, tpi, tun_dst, dscp_ecn_decapsulate, 954 log_ecn_error); 955 } 956 957 rcu_read_unlock(); 958 959 return ret; 960 961 drop: 962 rcu_read_unlock(); 963 kfree_skb(skb); 964 return 0; 965 } 966 967 static int ip4ip6_rcv(struct sk_buff *skb) 968 { 969 return ipxip6_rcv(skb, IPPROTO_IPIP, &tpi_v4, 970 ip4ip6_dscp_ecn_decapsulate); 971 } 972 973 static int ip6ip6_rcv(struct sk_buff *skb) 974 { 975 return ipxip6_rcv(skb, IPPROTO_IPV6, &tpi_v6, 976 ip6ip6_dscp_ecn_decapsulate); 977 } 978 979 static int mplsip6_rcv(struct sk_buff *skb) 980 { 981 return ipxip6_rcv(skb, IPPROTO_MPLS, &tpi_mpls, 982 mplsip6_dscp_ecn_decapsulate); 983 } 984 985 struct ipv6_tel_txoption { 986 struct ipv6_txoptions ops; 987 __u8 dst_opt[8]; 988 }; 989 990 static void init_tel_txopt(struct ipv6_tel_txoption *opt, __u8 encap_limit) 991 { 992 memset(opt, 0, sizeof(struct ipv6_tel_txoption)); 993 994 opt->dst_opt[2] = IPV6_TLV_TNL_ENCAP_LIMIT; 995 opt->dst_opt[3] = 1; 996 opt->dst_opt[4] = encap_limit; 997 opt->dst_opt[5] = IPV6_TLV_PADN; 998 opt->dst_opt[6] = 1; 999 1000 opt->ops.dst1opt = (struct ipv6_opt_hdr *) opt->dst_opt; 1001 opt->ops.opt_nflen = 8; 1002 } 1003 1004 /** 1005 * ip6_tnl_addr_conflict - compare packet addresses to tunnel's own 1006 * @t: the outgoing tunnel device 1007 * @hdr: IPv6 header from the incoming packet 1008 * 1009 * Description: 1010 * Avoid trivial tunneling loop by checking that tunnel exit-point 1011 * doesn't match source of incoming packet. 1012 * 1013 * Return: 1014 * 1 if conflict, 1015 * 0 else 1016 **/ 1017 1018 static inline bool 1019 ip6_tnl_addr_conflict(const struct ip6_tnl *t, const struct ipv6hdr *hdr) 1020 { 1021 return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr); 1022 } 1023 1024 int ip6_tnl_xmit_ctl(struct ip6_tnl *t, 1025 const struct in6_addr *laddr, 1026 const struct in6_addr *raddr) 1027 { 1028 struct __ip6_tnl_parm *p = &t->parms; 1029 int ret = 0; 1030 struct net *net = t->net; 1031 1032 if (t->parms.collect_md) 1033 return 1; 1034 1035 if ((p->flags & IP6_TNL_F_CAP_XMIT) || 1036 ((p->flags & IP6_TNL_F_CAP_PER_PACKET) && 1037 (ip6_tnl_get_cap(t, laddr, raddr) & IP6_TNL_F_CAP_XMIT))) { 1038 struct net_device *ldev = NULL; 1039 1040 rcu_read_lock(); 1041 if (p->link) 1042 ldev = dev_get_by_index_rcu(net, p->link); 1043 1044 if (unlikely(!ipv6_chk_addr_and_flags(net, laddr, ldev, false, 1045 0, IFA_F_TENTATIVE))) 1046 pr_warn_ratelimited("%s xmit: Local address not yet configured!\n", 1047 p->name); 1048 else if (!(p->flags & IP6_TNL_F_ALLOW_LOCAL_REMOTE) && 1049 !ipv6_addr_is_multicast(raddr) && 1050 unlikely(ipv6_chk_addr_and_flags(net, raddr, ldev, 1051 true, 0, IFA_F_TENTATIVE))) 1052 pr_warn_ratelimited("%s xmit: Routing loop! Remote address found on this node!\n", 1053 p->name); 1054 else 1055 ret = 1; 1056 rcu_read_unlock(); 1057 } 1058 return ret; 1059 } 1060 EXPORT_SYMBOL_GPL(ip6_tnl_xmit_ctl); 1061 1062 /** 1063 * ip6_tnl_xmit - encapsulate packet and send 1064 * @skb: the outgoing socket buffer 1065 * @dev: the outgoing tunnel device 1066 * @dsfield: dscp code for outer header 1067 * @fl6: flow of tunneled packet 1068 * @encap_limit: encapsulation limit 1069 * @pmtu: Path MTU is stored if packet is too big 1070 * @proto: next header value 1071 * 1072 * Description: 1073 * Build new header and do some sanity checks on the packet before sending 1074 * it. 1075 * 1076 * Return: 1077 * 0 on success 1078 * -1 fail 1079 * %-EMSGSIZE message too big. return mtu in this case. 1080 **/ 1081 1082 int ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev, __u8 dsfield, 1083 struct flowi6 *fl6, int encap_limit, __u32 *pmtu, 1084 __u8 proto) 1085 { 1086 struct ip6_tnl *t = netdev_priv(dev); 1087 struct net *net = t->net; 1088 struct ipv6hdr *ipv6h; 1089 struct ipv6_tel_txoption opt; 1090 struct dst_entry *dst = NULL, *ndst = NULL; 1091 struct net_device *tdev; 1092 int mtu; 1093 unsigned int eth_hlen = t->dev->type == ARPHRD_ETHER ? ETH_HLEN : 0; 1094 unsigned int psh_hlen = sizeof(struct ipv6hdr) + t->encap_hlen; 1095 unsigned int max_headroom = psh_hlen; 1096 __be16 payload_protocol; 1097 bool use_cache = false; 1098 u8 hop_limit; 1099 int err = -1; 1100 1101 payload_protocol = skb_protocol(skb, true); 1102 1103 if (t->parms.collect_md) { 1104 hop_limit = skb_tunnel_info(skb)->key.ttl; 1105 goto route_lookup; 1106 } else { 1107 hop_limit = t->parms.hop_limit; 1108 } 1109 1110 /* NBMA tunnel */ 1111 if (ipv6_addr_any(&t->parms.raddr)) { 1112 if (payload_protocol == htons(ETH_P_IPV6)) { 1113 struct in6_addr *addr6; 1114 struct neighbour *neigh; 1115 int addr_type; 1116 1117 if (!skb_dst(skb)) 1118 goto tx_err_link_failure; 1119 1120 neigh = dst_neigh_lookup(skb_dst(skb), 1121 &ipv6_hdr(skb)->daddr); 1122 if (!neigh) 1123 goto tx_err_link_failure; 1124 1125 addr6 = (struct in6_addr *)&neigh->primary_key; 1126 addr_type = ipv6_addr_type(addr6); 1127 1128 if (addr_type == IPV6_ADDR_ANY) 1129 addr6 = &ipv6_hdr(skb)->daddr; 1130 1131 memcpy(&fl6->daddr, addr6, sizeof(fl6->daddr)); 1132 neigh_release(neigh); 1133 } else if (payload_protocol == htons(ETH_P_IP)) { 1134 const struct rtable *rt = skb_rtable(skb); 1135 1136 if (!rt) 1137 goto tx_err_link_failure; 1138 1139 if (rt->rt_gw_family == AF_INET6) 1140 memcpy(&fl6->daddr, &rt->rt_gw6, sizeof(fl6->daddr)); 1141 } 1142 } else if (t->parms.proto != 0 && !(t->parms.flags & 1143 (IP6_TNL_F_USE_ORIG_TCLASS | 1144 IP6_TNL_F_USE_ORIG_FWMARK))) { 1145 /* enable the cache only if neither the outer protocol nor the 1146 * routing decision depends on the current inner header value 1147 */ 1148 use_cache = true; 1149 } 1150 1151 if (use_cache) 1152 dst = dst_cache_get(&t->dst_cache); 1153 1154 if (!ip6_tnl_xmit_ctl(t, &fl6->saddr, &fl6->daddr)) 1155 goto tx_err_link_failure; 1156 1157 if (!dst) { 1158 route_lookup: 1159 /* add dsfield to flowlabel for route lookup */ 1160 fl6->flowlabel = ip6_make_flowinfo(dsfield, fl6->flowlabel); 1161 1162 dst = ip6_route_output(net, NULL, fl6); 1163 1164 if (dst->error) 1165 goto tx_err_link_failure; 1166 dst = xfrm_lookup(net, dst, flowi6_to_flowi(fl6), NULL, 0); 1167 if (IS_ERR(dst)) { 1168 err = PTR_ERR(dst); 1169 dst = NULL; 1170 goto tx_err_link_failure; 1171 } 1172 if (t->parms.collect_md && ipv6_addr_any(&fl6->saddr) && 1173 ipv6_dev_get_saddr(net, ip6_dst_idev(dst)->dev, 1174 &fl6->daddr, 0, &fl6->saddr)) 1175 goto tx_err_link_failure; 1176 ndst = dst; 1177 } 1178 1179 tdev = dst->dev; 1180 1181 if (tdev == dev) { 1182 DEV_STATS_INC(dev, collisions); 1183 net_warn_ratelimited("%s: Local routing loop detected!\n", 1184 t->parms.name); 1185 goto tx_err_dst_release; 1186 } 1187 mtu = dst_mtu(dst) - eth_hlen - psh_hlen - t->tun_hlen; 1188 if (encap_limit >= 0) { 1189 max_headroom += 8; 1190 mtu -= 8; 1191 } 1192 mtu = max(mtu, skb->protocol == htons(ETH_P_IPV6) ? 1193 IPV6_MIN_MTU : IPV4_MIN_MTU); 1194 1195 skb_dst_update_pmtu_no_confirm(skb, mtu); 1196 if (skb->len - t->tun_hlen - eth_hlen > mtu && !skb_is_gso(skb)) { 1197 *pmtu = mtu; 1198 err = -EMSGSIZE; 1199 goto tx_err_dst_release; 1200 } 1201 1202 if (t->err_count > 0) { 1203 if (time_before(jiffies, 1204 t->err_time + IP6TUNNEL_ERR_TIMEO)) { 1205 t->err_count--; 1206 1207 dst_link_failure(skb); 1208 } else { 1209 t->err_count = 0; 1210 } 1211 } 1212 1213 skb_scrub_packet(skb, !net_eq(t->net, dev_net(dev))); 1214 1215 /* 1216 * Okay, now see if we can stuff it in the buffer as-is. 1217 */ 1218 max_headroom += LL_RESERVED_SPACE(tdev); 1219 1220 if (skb_headroom(skb) < max_headroom || skb_shared(skb) || 1221 (skb_cloned(skb) && !skb_clone_writable(skb, 0))) { 1222 struct sk_buff *new_skb; 1223 1224 new_skb = skb_realloc_headroom(skb, max_headroom); 1225 if (!new_skb) 1226 goto tx_err_dst_release; 1227 1228 if (skb->sk) 1229 skb_set_owner_w(new_skb, skb->sk); 1230 consume_skb(skb); 1231 skb = new_skb; 1232 } 1233 1234 if (t->parms.collect_md) { 1235 if (t->encap.type != TUNNEL_ENCAP_NONE) 1236 goto tx_err_dst_release; 1237 } else { 1238 if (use_cache && ndst) 1239 dst_cache_set_ip6(&t->dst_cache, ndst, &fl6->saddr); 1240 } 1241 skb_dst_set(skb, dst); 1242 1243 if (hop_limit == 0) { 1244 if (payload_protocol == htons(ETH_P_IP)) 1245 hop_limit = ip_hdr(skb)->ttl; 1246 else if (payload_protocol == htons(ETH_P_IPV6)) 1247 hop_limit = ipv6_hdr(skb)->hop_limit; 1248 else 1249 hop_limit = ip6_dst_hoplimit(dst); 1250 } 1251 1252 /* Calculate max headroom for all the headers and adjust 1253 * needed_headroom if necessary. 1254 */ 1255 max_headroom = LL_RESERVED_SPACE(dst->dev) + sizeof(struct ipv6hdr) 1256 + dst->header_len + t->hlen; 1257 if (max_headroom > READ_ONCE(dev->needed_headroom)) 1258 WRITE_ONCE(dev->needed_headroom, max_headroom); 1259 1260 err = ip6_tnl_encap(skb, t, &proto, fl6); 1261 if (err) 1262 return err; 1263 1264 if (encap_limit >= 0) { 1265 init_tel_txopt(&opt, encap_limit); 1266 ipv6_push_frag_opts(skb, &opt.ops, &proto); 1267 } 1268 1269 skb_push(skb, sizeof(struct ipv6hdr)); 1270 skb_reset_network_header(skb); 1271 ipv6h = ipv6_hdr(skb); 1272 ip6_flow_hdr(ipv6h, dsfield, 1273 ip6_make_flowlabel(net, skb, fl6->flowlabel, true, fl6)); 1274 ipv6h->hop_limit = hop_limit; 1275 ipv6h->nexthdr = proto; 1276 ipv6h->saddr = fl6->saddr; 1277 ipv6h->daddr = fl6->daddr; 1278 ip6tunnel_xmit(NULL, skb, dev); 1279 return 0; 1280 tx_err_link_failure: 1281 DEV_STATS_INC(dev, tx_carrier_errors); 1282 dst_link_failure(skb); 1283 tx_err_dst_release: 1284 dst_release(dst); 1285 return err; 1286 } 1287 EXPORT_SYMBOL(ip6_tnl_xmit); 1288 1289 static inline int 1290 ipxip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev, 1291 u8 protocol) 1292 { 1293 struct ip6_tnl *t = netdev_priv(dev); 1294 struct ipv6hdr *ipv6h; 1295 const struct iphdr *iph; 1296 int encap_limit = -1; 1297 __u16 offset; 1298 struct flowi6 fl6; 1299 __u8 dsfield, orig_dsfield; 1300 __u32 mtu; 1301 u8 tproto; 1302 int err; 1303 1304 tproto = READ_ONCE(t->parms.proto); 1305 if (tproto != protocol && tproto != 0) 1306 return -1; 1307 1308 if (t->parms.collect_md) { 1309 struct ip_tunnel_info *tun_info; 1310 const struct ip_tunnel_key *key; 1311 1312 tun_info = skb_tunnel_info(skb); 1313 if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) || 1314 ip_tunnel_info_af(tun_info) != AF_INET6)) 1315 return -1; 1316 key = &tun_info->key; 1317 memset(&fl6, 0, sizeof(fl6)); 1318 fl6.flowi6_proto = protocol; 1319 fl6.saddr = key->u.ipv6.src; 1320 fl6.daddr = key->u.ipv6.dst; 1321 fl6.flowlabel = key->label; 1322 dsfield = key->tos; 1323 switch (protocol) { 1324 case IPPROTO_IPIP: 1325 iph = ip_hdr(skb); 1326 orig_dsfield = ipv4_get_dsfield(iph); 1327 break; 1328 case IPPROTO_IPV6: 1329 ipv6h = ipv6_hdr(skb); 1330 orig_dsfield = ipv6_get_dsfield(ipv6h); 1331 break; 1332 default: 1333 orig_dsfield = dsfield; 1334 break; 1335 } 1336 } else { 1337 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1338 encap_limit = t->parms.encap_limit; 1339 if (protocol == IPPROTO_IPV6) { 1340 offset = ip6_tnl_parse_tlv_enc_lim(skb, 1341 skb_network_header(skb)); 1342 /* ip6_tnl_parse_tlv_enc_lim() might have 1343 * reallocated skb->head 1344 */ 1345 if (offset > 0) { 1346 struct ipv6_tlv_tnl_enc_lim *tel; 1347 1348 tel = (void *)&skb_network_header(skb)[offset]; 1349 if (tel->encap_limit == 0) { 1350 icmpv6_ndo_send(skb, ICMPV6_PARAMPROB, 1351 ICMPV6_HDR_FIELD, offset + 2); 1352 return -1; 1353 } 1354 encap_limit = tel->encap_limit - 1; 1355 } 1356 } 1357 1358 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 1359 fl6.flowi6_proto = protocol; 1360 1361 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK) 1362 fl6.flowi6_mark = skb->mark; 1363 else 1364 fl6.flowi6_mark = t->parms.fwmark; 1365 switch (protocol) { 1366 case IPPROTO_IPIP: 1367 iph = ip_hdr(skb); 1368 orig_dsfield = ipv4_get_dsfield(iph); 1369 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) 1370 dsfield = orig_dsfield; 1371 else 1372 dsfield = ip6_tclass(t->parms.flowinfo); 1373 break; 1374 case IPPROTO_IPV6: 1375 ipv6h = ipv6_hdr(skb); 1376 orig_dsfield = ipv6_get_dsfield(ipv6h); 1377 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) 1378 dsfield = orig_dsfield; 1379 else 1380 dsfield = ip6_tclass(t->parms.flowinfo); 1381 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL) 1382 fl6.flowlabel |= ip6_flowlabel(ipv6h); 1383 break; 1384 default: 1385 orig_dsfield = dsfield = ip6_tclass(t->parms.flowinfo); 1386 break; 1387 } 1388 } 1389 1390 fl6.flowi6_uid = sock_net_uid(dev_net(dev), NULL); 1391 dsfield = INET_ECN_encapsulate(dsfield, orig_dsfield); 1392 1393 if (iptunnel_handle_offloads(skb, SKB_GSO_IPXIP6)) 1394 return -1; 1395 1396 skb_set_inner_ipproto(skb, protocol); 1397 1398 err = ip6_tnl_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu, 1399 protocol); 1400 if (err != 0) { 1401 /* XXX: send ICMP error even if DF is not set. */ 1402 if (err == -EMSGSIZE) 1403 switch (protocol) { 1404 case IPPROTO_IPIP: 1405 icmp_ndo_send(skb, ICMP_DEST_UNREACH, 1406 ICMP_FRAG_NEEDED, htonl(mtu)); 1407 break; 1408 case IPPROTO_IPV6: 1409 icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); 1410 break; 1411 default: 1412 break; 1413 } 1414 return -1; 1415 } 1416 1417 return 0; 1418 } 1419 1420 static netdev_tx_t 1421 ip6_tnl_start_xmit(struct sk_buff *skb, struct net_device *dev) 1422 { 1423 struct ip6_tnl *t = netdev_priv(dev); 1424 u8 ipproto; 1425 int ret; 1426 1427 if (!pskb_inet_may_pull(skb)) 1428 goto tx_err; 1429 1430 switch (skb->protocol) { 1431 case htons(ETH_P_IP): 1432 ipproto = IPPROTO_IPIP; 1433 break; 1434 case htons(ETH_P_IPV6): 1435 if (ip6_tnl_addr_conflict(t, ipv6_hdr(skb))) 1436 goto tx_err; 1437 ipproto = IPPROTO_IPV6; 1438 break; 1439 case htons(ETH_P_MPLS_UC): 1440 ipproto = IPPROTO_MPLS; 1441 break; 1442 default: 1443 goto tx_err; 1444 } 1445 1446 ret = ipxip6_tnl_xmit(skb, dev, ipproto); 1447 if (ret < 0) 1448 goto tx_err; 1449 1450 return NETDEV_TX_OK; 1451 1452 tx_err: 1453 DEV_STATS_INC(dev, tx_errors); 1454 DEV_STATS_INC(dev, tx_dropped); 1455 kfree_skb(skb); 1456 return NETDEV_TX_OK; 1457 } 1458 1459 static void ip6_tnl_link_config(struct ip6_tnl *t) 1460 { 1461 struct net_device *dev = t->dev; 1462 struct net_device *tdev = NULL; 1463 struct __ip6_tnl_parm *p = &t->parms; 1464 struct flowi6 *fl6 = &t->fl.u.ip6; 1465 int t_hlen; 1466 int mtu; 1467 1468 __dev_addr_set(dev, &p->laddr, sizeof(struct in6_addr)); 1469 memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr)); 1470 1471 /* Set up flowi template */ 1472 fl6->saddr = p->laddr; 1473 fl6->daddr = p->raddr; 1474 fl6->flowi6_oif = p->link; 1475 fl6->flowlabel = 0; 1476 1477 if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS)) 1478 fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo; 1479 if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL)) 1480 fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo; 1481 1482 p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET); 1483 p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr); 1484 1485 if (p->flags&IP6_TNL_F_CAP_XMIT && p->flags&IP6_TNL_F_CAP_RCV) 1486 dev->flags |= IFF_POINTOPOINT; 1487 else 1488 dev->flags &= ~IFF_POINTOPOINT; 1489 1490 t->tun_hlen = 0; 1491 t->hlen = t->encap_hlen + t->tun_hlen; 1492 t_hlen = t->hlen + sizeof(struct ipv6hdr); 1493 1494 if (p->flags & IP6_TNL_F_CAP_XMIT) { 1495 int strict = (ipv6_addr_type(&p->raddr) & 1496 (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL)); 1497 1498 struct rt6_info *rt = rt6_lookup(t->net, 1499 &p->raddr, &p->laddr, 1500 p->link, NULL, strict); 1501 if (rt) { 1502 tdev = rt->dst.dev; 1503 ip6_rt_put(rt); 1504 } 1505 1506 if (!tdev && p->link) 1507 tdev = __dev_get_by_index(t->net, p->link); 1508 1509 if (tdev) { 1510 dev->hard_header_len = tdev->hard_header_len + t_hlen; 1511 mtu = min_t(unsigned int, tdev->mtu, IP6_MAX_MTU); 1512 1513 mtu = mtu - t_hlen; 1514 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1515 mtu -= 8; 1516 1517 if (mtu < IPV6_MIN_MTU) 1518 mtu = IPV6_MIN_MTU; 1519 WRITE_ONCE(dev->mtu, mtu); 1520 } 1521 } 1522 } 1523 1524 /** 1525 * ip6_tnl_change - update the tunnel parameters 1526 * @t: tunnel to be changed 1527 * @p: tunnel configuration parameters 1528 * 1529 * Description: 1530 * ip6_tnl_change() updates the tunnel parameters 1531 **/ 1532 1533 static void 1534 ip6_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p) 1535 { 1536 t->parms.laddr = p->laddr; 1537 t->parms.raddr = p->raddr; 1538 t->parms.flags = p->flags; 1539 t->parms.hop_limit = p->hop_limit; 1540 t->parms.encap_limit = p->encap_limit; 1541 t->parms.flowinfo = p->flowinfo; 1542 t->parms.link = p->link; 1543 t->parms.proto = p->proto; 1544 t->parms.fwmark = p->fwmark; 1545 dst_cache_reset(&t->dst_cache); 1546 ip6_tnl_link_config(t); 1547 } 1548 1549 static void ip6_tnl_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p) 1550 { 1551 struct net *net = t->net; 1552 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1553 1554 ip6_tnl_unlink(ip6n, t); 1555 synchronize_net(); 1556 ip6_tnl_change(t, p); 1557 ip6_tnl_link(ip6n, t); 1558 netdev_state_change(t->dev); 1559 } 1560 1561 static void ip6_tnl0_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p) 1562 { 1563 /* for default tnl0 device allow to change only the proto */ 1564 t->parms.proto = p->proto; 1565 netdev_state_change(t->dev); 1566 } 1567 1568 static void 1569 ip6_tnl_parm_from_user(struct __ip6_tnl_parm *p, const struct ip6_tnl_parm *u) 1570 { 1571 p->laddr = u->laddr; 1572 p->raddr = u->raddr; 1573 p->flags = u->flags; 1574 p->hop_limit = u->hop_limit; 1575 p->encap_limit = u->encap_limit; 1576 p->flowinfo = u->flowinfo; 1577 p->link = u->link; 1578 p->proto = u->proto; 1579 memcpy(p->name, u->name, sizeof(u->name)); 1580 } 1581 1582 static void 1583 ip6_tnl_parm_to_user(struct ip6_tnl_parm *u, const struct __ip6_tnl_parm *p) 1584 { 1585 u->laddr = p->laddr; 1586 u->raddr = p->raddr; 1587 u->flags = p->flags; 1588 u->hop_limit = p->hop_limit; 1589 u->encap_limit = p->encap_limit; 1590 u->flowinfo = p->flowinfo; 1591 u->link = p->link; 1592 u->proto = p->proto; 1593 memcpy(u->name, p->name, sizeof(u->name)); 1594 } 1595 1596 /** 1597 * ip6_tnl_siocdevprivate - configure ipv6 tunnels from userspace 1598 * @dev: virtual device associated with tunnel 1599 * @ifr: unused 1600 * @data: parameters passed from userspace 1601 * @cmd: command to be performed 1602 * 1603 * Description: 1604 * ip6_tnl_ioctl() is used for managing IPv6 tunnels 1605 * from userspace. 1606 * 1607 * The possible commands are the following: 1608 * %SIOCGETTUNNEL: get tunnel parameters for device 1609 * %SIOCADDTUNNEL: add tunnel matching given tunnel parameters 1610 * %SIOCCHGTUNNEL: change tunnel parameters to those given 1611 * %SIOCDELTUNNEL: delete tunnel 1612 * 1613 * The fallback device "ip6tnl0", created during module 1614 * initialization, can be used for creating other tunnel devices. 1615 * 1616 * Return: 1617 * 0 on success, 1618 * %-EFAULT if unable to copy data to or from userspace, 1619 * %-EPERM if current process hasn't %CAP_NET_ADMIN set 1620 * %-EINVAL if passed tunnel parameters are invalid, 1621 * %-EEXIST if changing a tunnel's parameters would cause a conflict 1622 * %-ENODEV if attempting to change or delete a nonexisting device 1623 **/ 1624 1625 static int 1626 ip6_tnl_siocdevprivate(struct net_device *dev, struct ifreq *ifr, 1627 void __user *data, int cmd) 1628 { 1629 int err = 0; 1630 struct ip6_tnl_parm p; 1631 struct __ip6_tnl_parm p1; 1632 struct ip6_tnl *t = netdev_priv(dev); 1633 struct net *net = t->net; 1634 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1635 1636 memset(&p1, 0, sizeof(p1)); 1637 1638 switch (cmd) { 1639 case SIOCGETTUNNEL: 1640 if (dev == ip6n->fb_tnl_dev) { 1641 if (copy_from_user(&p, data, sizeof(p))) { 1642 err = -EFAULT; 1643 break; 1644 } 1645 ip6_tnl_parm_from_user(&p1, &p); 1646 t = ip6_tnl_locate(net, &p1, 0); 1647 if (IS_ERR(t)) 1648 t = netdev_priv(dev); 1649 } else { 1650 memset(&p, 0, sizeof(p)); 1651 } 1652 ip6_tnl_parm_to_user(&p, &t->parms); 1653 if (copy_to_user(data, &p, sizeof(p))) 1654 err = -EFAULT; 1655 break; 1656 case SIOCADDTUNNEL: 1657 case SIOCCHGTUNNEL: 1658 err = -EPERM; 1659 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 1660 break; 1661 err = -EFAULT; 1662 if (copy_from_user(&p, data, sizeof(p))) 1663 break; 1664 err = -EINVAL; 1665 if (p.proto != IPPROTO_IPV6 && p.proto != IPPROTO_IPIP && 1666 p.proto != 0) 1667 break; 1668 ip6_tnl_parm_from_user(&p1, &p); 1669 t = ip6_tnl_locate(net, &p1, cmd == SIOCADDTUNNEL); 1670 if (cmd == SIOCCHGTUNNEL) { 1671 if (!IS_ERR(t)) { 1672 if (t->dev != dev) { 1673 err = -EEXIST; 1674 break; 1675 } 1676 } else 1677 t = netdev_priv(dev); 1678 if (dev == ip6n->fb_tnl_dev) 1679 ip6_tnl0_update(t, &p1); 1680 else 1681 ip6_tnl_update(t, &p1); 1682 } 1683 if (!IS_ERR(t)) { 1684 err = 0; 1685 ip6_tnl_parm_to_user(&p, &t->parms); 1686 if (copy_to_user(data, &p, sizeof(p))) 1687 err = -EFAULT; 1688 1689 } else { 1690 err = PTR_ERR(t); 1691 } 1692 break; 1693 case SIOCDELTUNNEL: 1694 err = -EPERM; 1695 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 1696 break; 1697 1698 if (dev == ip6n->fb_tnl_dev) { 1699 err = -EFAULT; 1700 if (copy_from_user(&p, data, sizeof(p))) 1701 break; 1702 err = -ENOENT; 1703 ip6_tnl_parm_from_user(&p1, &p); 1704 t = ip6_tnl_locate(net, &p1, 0); 1705 if (IS_ERR(t)) 1706 break; 1707 err = -EPERM; 1708 if (t->dev == ip6n->fb_tnl_dev) 1709 break; 1710 dev = t->dev; 1711 } 1712 err = 0; 1713 unregister_netdevice(dev); 1714 break; 1715 default: 1716 err = -EINVAL; 1717 } 1718 return err; 1719 } 1720 1721 /** 1722 * ip6_tnl_change_mtu - change mtu manually for tunnel device 1723 * @dev: virtual device associated with tunnel 1724 * @new_mtu: the new mtu 1725 * 1726 * Return: 1727 * 0 on success, 1728 * %-EINVAL if mtu too small 1729 **/ 1730 1731 int ip6_tnl_change_mtu(struct net_device *dev, int new_mtu) 1732 { 1733 struct ip6_tnl *tnl = netdev_priv(dev); 1734 1735 if (tnl->parms.proto == IPPROTO_IPV6) { 1736 if (new_mtu < IPV6_MIN_MTU) 1737 return -EINVAL; 1738 } else { 1739 if (new_mtu < ETH_MIN_MTU) 1740 return -EINVAL; 1741 } 1742 if (tnl->parms.proto == IPPROTO_IPV6 || tnl->parms.proto == 0) { 1743 if (new_mtu > IP6_MAX_MTU - dev->hard_header_len) 1744 return -EINVAL; 1745 } else { 1746 if (new_mtu > IP_MAX_MTU - dev->hard_header_len) 1747 return -EINVAL; 1748 } 1749 WRITE_ONCE(dev->mtu, new_mtu); 1750 return 0; 1751 } 1752 EXPORT_SYMBOL(ip6_tnl_change_mtu); 1753 1754 int ip6_tnl_get_iflink(const struct net_device *dev) 1755 { 1756 struct ip6_tnl *t = netdev_priv(dev); 1757 1758 return READ_ONCE(t->parms.link); 1759 } 1760 EXPORT_SYMBOL(ip6_tnl_get_iflink); 1761 1762 int ip6_tnl_encap_add_ops(const struct ip6_tnl_encap_ops *ops, 1763 unsigned int num) 1764 { 1765 if (num >= MAX_IPTUN_ENCAP_OPS) 1766 return -ERANGE; 1767 1768 return !cmpxchg((const struct ip6_tnl_encap_ops **) 1769 &ip6tun_encaps[num], 1770 NULL, ops) ? 0 : -1; 1771 } 1772 EXPORT_SYMBOL(ip6_tnl_encap_add_ops); 1773 1774 int ip6_tnl_encap_del_ops(const struct ip6_tnl_encap_ops *ops, 1775 unsigned int num) 1776 { 1777 int ret; 1778 1779 if (num >= MAX_IPTUN_ENCAP_OPS) 1780 return -ERANGE; 1781 1782 ret = (cmpxchg((const struct ip6_tnl_encap_ops **) 1783 &ip6tun_encaps[num], 1784 ops, NULL) == ops) ? 0 : -1; 1785 1786 synchronize_net(); 1787 1788 return ret; 1789 } 1790 EXPORT_SYMBOL(ip6_tnl_encap_del_ops); 1791 1792 int ip6_tnl_encap_setup(struct ip6_tnl *t, 1793 struct ip_tunnel_encap *ipencap) 1794 { 1795 int hlen; 1796 1797 memset(&t->encap, 0, sizeof(t->encap)); 1798 1799 hlen = ip6_encap_hlen(ipencap); 1800 if (hlen < 0) 1801 return hlen; 1802 1803 t->encap.type = ipencap->type; 1804 t->encap.sport = ipencap->sport; 1805 t->encap.dport = ipencap->dport; 1806 t->encap.flags = ipencap->flags; 1807 1808 t->encap_hlen = hlen; 1809 t->hlen = t->encap_hlen + t->tun_hlen; 1810 1811 return 0; 1812 } 1813 EXPORT_SYMBOL_GPL(ip6_tnl_encap_setup); 1814 1815 static const struct net_device_ops ip6_tnl_netdev_ops = { 1816 .ndo_init = ip6_tnl_dev_init, 1817 .ndo_uninit = ip6_tnl_dev_uninit, 1818 .ndo_start_xmit = ip6_tnl_start_xmit, 1819 .ndo_siocdevprivate = ip6_tnl_siocdevprivate, 1820 .ndo_change_mtu = ip6_tnl_change_mtu, 1821 .ndo_get_stats64 = dev_get_tstats64, 1822 .ndo_get_iflink = ip6_tnl_get_iflink, 1823 }; 1824 1825 #define IPXIPX_FEATURES (NETIF_F_SG | \ 1826 NETIF_F_FRAGLIST | \ 1827 NETIF_F_HIGHDMA | \ 1828 NETIF_F_GSO_SOFTWARE | \ 1829 NETIF_F_HW_CSUM) 1830 1831 /** 1832 * ip6_tnl_dev_setup - setup virtual tunnel device 1833 * @dev: virtual device associated with tunnel 1834 * 1835 * Description: 1836 * Initialize function pointers and device parameters 1837 **/ 1838 1839 static void ip6_tnl_dev_setup(struct net_device *dev) 1840 { 1841 dev->netdev_ops = &ip6_tnl_netdev_ops; 1842 dev->header_ops = &ip_tunnel_header_ops; 1843 dev->needs_free_netdev = true; 1844 dev->priv_destructor = ip6_dev_free; 1845 1846 dev->type = ARPHRD_TUNNEL6; 1847 dev->flags |= IFF_NOARP; 1848 dev->addr_len = sizeof(struct in6_addr); 1849 dev->features |= NETIF_F_LLTX; 1850 dev->pcpu_stat_type = NETDEV_PCPU_STAT_TSTATS; 1851 netif_keep_dst(dev); 1852 1853 dev->features |= IPXIPX_FEATURES; 1854 dev->hw_features |= IPXIPX_FEATURES; 1855 1856 /* This perm addr will be used as interface identifier by IPv6 */ 1857 dev->addr_assign_type = NET_ADDR_RANDOM; 1858 eth_random_addr(dev->perm_addr); 1859 } 1860 1861 1862 /** 1863 * ip6_tnl_dev_init_gen - general initializer for all tunnel devices 1864 * @dev: virtual device associated with tunnel 1865 **/ 1866 1867 static inline int 1868 ip6_tnl_dev_init_gen(struct net_device *dev) 1869 { 1870 struct ip6_tnl *t = netdev_priv(dev); 1871 int ret; 1872 int t_hlen; 1873 1874 t->dev = dev; 1875 t->net = dev_net(dev); 1876 1877 ret = dst_cache_init(&t->dst_cache, GFP_KERNEL); 1878 if (ret) 1879 return ret; 1880 1881 ret = gro_cells_init(&t->gro_cells, dev); 1882 if (ret) 1883 goto destroy_dst; 1884 1885 t->tun_hlen = 0; 1886 t->hlen = t->encap_hlen + t->tun_hlen; 1887 t_hlen = t->hlen + sizeof(struct ipv6hdr); 1888 1889 dev->type = ARPHRD_TUNNEL6; 1890 dev->hard_header_len = LL_MAX_HEADER + t_hlen; 1891 dev->mtu = ETH_DATA_LEN - t_hlen; 1892 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1893 dev->mtu -= 8; 1894 dev->min_mtu = ETH_MIN_MTU; 1895 dev->max_mtu = IP6_MAX_MTU - dev->hard_header_len; 1896 1897 netdev_hold(dev, &t->dev_tracker, GFP_KERNEL); 1898 netdev_lockdep_set_classes(dev); 1899 return 0; 1900 1901 destroy_dst: 1902 dst_cache_destroy(&t->dst_cache); 1903 1904 return ret; 1905 } 1906 1907 /** 1908 * ip6_tnl_dev_init - initializer for all non fallback tunnel devices 1909 * @dev: virtual device associated with tunnel 1910 **/ 1911 1912 static int ip6_tnl_dev_init(struct net_device *dev) 1913 { 1914 struct ip6_tnl *t = netdev_priv(dev); 1915 int err = ip6_tnl_dev_init_gen(dev); 1916 1917 if (err) 1918 return err; 1919 ip6_tnl_link_config(t); 1920 if (t->parms.collect_md) 1921 netif_keep_dst(dev); 1922 return 0; 1923 } 1924 1925 /** 1926 * ip6_fb_tnl_dev_init - initializer for fallback tunnel device 1927 * @dev: fallback device 1928 * 1929 * Return: 0 1930 **/ 1931 1932 static int __net_init ip6_fb_tnl_dev_init(struct net_device *dev) 1933 { 1934 struct ip6_tnl *t = netdev_priv(dev); 1935 struct net *net = dev_net(dev); 1936 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1937 1938 t->parms.proto = IPPROTO_IPV6; 1939 1940 rcu_assign_pointer(ip6n->tnls_wc[0], t); 1941 return 0; 1942 } 1943 1944 static int ip6_tnl_validate(struct nlattr *tb[], struct nlattr *data[], 1945 struct netlink_ext_ack *extack) 1946 { 1947 u8 proto; 1948 1949 if (!data || !data[IFLA_IPTUN_PROTO]) 1950 return 0; 1951 1952 proto = nla_get_u8(data[IFLA_IPTUN_PROTO]); 1953 if (proto != IPPROTO_IPV6 && 1954 proto != IPPROTO_IPIP && 1955 proto != 0) 1956 return -EINVAL; 1957 1958 return 0; 1959 } 1960 1961 static void ip6_tnl_netlink_parms(struct nlattr *data[], 1962 struct __ip6_tnl_parm *parms) 1963 { 1964 memset(parms, 0, sizeof(*parms)); 1965 1966 if (!data) 1967 return; 1968 1969 if (data[IFLA_IPTUN_LINK]) 1970 parms->link = nla_get_u32(data[IFLA_IPTUN_LINK]); 1971 1972 if (data[IFLA_IPTUN_LOCAL]) 1973 parms->laddr = nla_get_in6_addr(data[IFLA_IPTUN_LOCAL]); 1974 1975 if (data[IFLA_IPTUN_REMOTE]) 1976 parms->raddr = nla_get_in6_addr(data[IFLA_IPTUN_REMOTE]); 1977 1978 if (data[IFLA_IPTUN_TTL]) 1979 parms->hop_limit = nla_get_u8(data[IFLA_IPTUN_TTL]); 1980 1981 if (data[IFLA_IPTUN_ENCAP_LIMIT]) 1982 parms->encap_limit = nla_get_u8(data[IFLA_IPTUN_ENCAP_LIMIT]); 1983 1984 if (data[IFLA_IPTUN_FLOWINFO]) 1985 parms->flowinfo = nla_get_be32(data[IFLA_IPTUN_FLOWINFO]); 1986 1987 if (data[IFLA_IPTUN_FLAGS]) 1988 parms->flags = nla_get_u32(data[IFLA_IPTUN_FLAGS]); 1989 1990 if (data[IFLA_IPTUN_PROTO]) 1991 parms->proto = nla_get_u8(data[IFLA_IPTUN_PROTO]); 1992 1993 if (data[IFLA_IPTUN_COLLECT_METADATA]) 1994 parms->collect_md = true; 1995 1996 if (data[IFLA_IPTUN_FWMARK]) 1997 parms->fwmark = nla_get_u32(data[IFLA_IPTUN_FWMARK]); 1998 } 1999 2000 static int ip6_tnl_newlink(struct net *src_net, struct net_device *dev, 2001 struct nlattr *tb[], struct nlattr *data[], 2002 struct netlink_ext_ack *extack) 2003 { 2004 struct net *net = dev_net(dev); 2005 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 2006 struct ip_tunnel_encap ipencap; 2007 struct ip6_tnl *nt, *t; 2008 int err; 2009 2010 nt = netdev_priv(dev); 2011 2012 if (ip_tunnel_netlink_encap_parms(data, &ipencap)) { 2013 err = ip6_tnl_encap_setup(nt, &ipencap); 2014 if (err < 0) 2015 return err; 2016 } 2017 2018 ip6_tnl_netlink_parms(data, &nt->parms); 2019 2020 if (nt->parms.collect_md) { 2021 if (rtnl_dereference(ip6n->collect_md_tun)) 2022 return -EEXIST; 2023 } else { 2024 t = ip6_tnl_locate(net, &nt->parms, 0); 2025 if (!IS_ERR(t)) 2026 return -EEXIST; 2027 } 2028 2029 err = ip6_tnl_create2(dev); 2030 if (!err && tb[IFLA_MTU]) 2031 ip6_tnl_change_mtu(dev, nla_get_u32(tb[IFLA_MTU])); 2032 2033 return err; 2034 } 2035 2036 static int ip6_tnl_changelink(struct net_device *dev, struct nlattr *tb[], 2037 struct nlattr *data[], 2038 struct netlink_ext_ack *extack) 2039 { 2040 struct ip6_tnl *t = netdev_priv(dev); 2041 struct __ip6_tnl_parm p; 2042 struct net *net = t->net; 2043 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 2044 struct ip_tunnel_encap ipencap; 2045 2046 if (dev == ip6n->fb_tnl_dev) 2047 return -EINVAL; 2048 2049 if (ip_tunnel_netlink_encap_parms(data, &ipencap)) { 2050 int err = ip6_tnl_encap_setup(t, &ipencap); 2051 2052 if (err < 0) 2053 return err; 2054 } 2055 ip6_tnl_netlink_parms(data, &p); 2056 if (p.collect_md) 2057 return -EINVAL; 2058 2059 t = ip6_tnl_locate(net, &p, 0); 2060 if (!IS_ERR(t)) { 2061 if (t->dev != dev) 2062 return -EEXIST; 2063 } else 2064 t = netdev_priv(dev); 2065 2066 ip6_tnl_update(t, &p); 2067 return 0; 2068 } 2069 2070 static void ip6_tnl_dellink(struct net_device *dev, struct list_head *head) 2071 { 2072 struct net *net = dev_net(dev); 2073 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 2074 2075 if (dev != ip6n->fb_tnl_dev) 2076 unregister_netdevice_queue(dev, head); 2077 } 2078 2079 static size_t ip6_tnl_get_size(const struct net_device *dev) 2080 { 2081 return 2082 /* IFLA_IPTUN_LINK */ 2083 nla_total_size(4) + 2084 /* IFLA_IPTUN_LOCAL */ 2085 nla_total_size(sizeof(struct in6_addr)) + 2086 /* IFLA_IPTUN_REMOTE */ 2087 nla_total_size(sizeof(struct in6_addr)) + 2088 /* IFLA_IPTUN_TTL */ 2089 nla_total_size(1) + 2090 /* IFLA_IPTUN_ENCAP_LIMIT */ 2091 nla_total_size(1) + 2092 /* IFLA_IPTUN_FLOWINFO */ 2093 nla_total_size(4) + 2094 /* IFLA_IPTUN_FLAGS */ 2095 nla_total_size(4) + 2096 /* IFLA_IPTUN_PROTO */ 2097 nla_total_size(1) + 2098 /* IFLA_IPTUN_ENCAP_TYPE */ 2099 nla_total_size(2) + 2100 /* IFLA_IPTUN_ENCAP_FLAGS */ 2101 nla_total_size(2) + 2102 /* IFLA_IPTUN_ENCAP_SPORT */ 2103 nla_total_size(2) + 2104 /* IFLA_IPTUN_ENCAP_DPORT */ 2105 nla_total_size(2) + 2106 /* IFLA_IPTUN_COLLECT_METADATA */ 2107 nla_total_size(0) + 2108 /* IFLA_IPTUN_FWMARK */ 2109 nla_total_size(4) + 2110 0; 2111 } 2112 2113 static int ip6_tnl_fill_info(struct sk_buff *skb, const struct net_device *dev) 2114 { 2115 struct ip6_tnl *tunnel = netdev_priv(dev); 2116 struct __ip6_tnl_parm *parm = &tunnel->parms; 2117 2118 if (nla_put_u32(skb, IFLA_IPTUN_LINK, parm->link) || 2119 nla_put_in6_addr(skb, IFLA_IPTUN_LOCAL, &parm->laddr) || 2120 nla_put_in6_addr(skb, IFLA_IPTUN_REMOTE, &parm->raddr) || 2121 nla_put_u8(skb, IFLA_IPTUN_TTL, parm->hop_limit) || 2122 nla_put_u8(skb, IFLA_IPTUN_ENCAP_LIMIT, parm->encap_limit) || 2123 nla_put_be32(skb, IFLA_IPTUN_FLOWINFO, parm->flowinfo) || 2124 nla_put_u32(skb, IFLA_IPTUN_FLAGS, parm->flags) || 2125 nla_put_u8(skb, IFLA_IPTUN_PROTO, parm->proto) || 2126 nla_put_u32(skb, IFLA_IPTUN_FWMARK, parm->fwmark)) 2127 goto nla_put_failure; 2128 2129 if (nla_put_u16(skb, IFLA_IPTUN_ENCAP_TYPE, tunnel->encap.type) || 2130 nla_put_be16(skb, IFLA_IPTUN_ENCAP_SPORT, tunnel->encap.sport) || 2131 nla_put_be16(skb, IFLA_IPTUN_ENCAP_DPORT, tunnel->encap.dport) || 2132 nla_put_u16(skb, IFLA_IPTUN_ENCAP_FLAGS, tunnel->encap.flags)) 2133 goto nla_put_failure; 2134 2135 if (parm->collect_md) 2136 if (nla_put_flag(skb, IFLA_IPTUN_COLLECT_METADATA)) 2137 goto nla_put_failure; 2138 2139 return 0; 2140 2141 nla_put_failure: 2142 return -EMSGSIZE; 2143 } 2144 2145 struct net *ip6_tnl_get_link_net(const struct net_device *dev) 2146 { 2147 struct ip6_tnl *tunnel = netdev_priv(dev); 2148 2149 return READ_ONCE(tunnel->net); 2150 } 2151 EXPORT_SYMBOL(ip6_tnl_get_link_net); 2152 2153 static const struct nla_policy ip6_tnl_policy[IFLA_IPTUN_MAX + 1] = { 2154 [IFLA_IPTUN_LINK] = { .type = NLA_U32 }, 2155 [IFLA_IPTUN_LOCAL] = { .len = sizeof(struct in6_addr) }, 2156 [IFLA_IPTUN_REMOTE] = { .len = sizeof(struct in6_addr) }, 2157 [IFLA_IPTUN_TTL] = { .type = NLA_U8 }, 2158 [IFLA_IPTUN_ENCAP_LIMIT] = { .type = NLA_U8 }, 2159 [IFLA_IPTUN_FLOWINFO] = { .type = NLA_U32 }, 2160 [IFLA_IPTUN_FLAGS] = { .type = NLA_U32 }, 2161 [IFLA_IPTUN_PROTO] = { .type = NLA_U8 }, 2162 [IFLA_IPTUN_ENCAP_TYPE] = { .type = NLA_U16 }, 2163 [IFLA_IPTUN_ENCAP_FLAGS] = { .type = NLA_U16 }, 2164 [IFLA_IPTUN_ENCAP_SPORT] = { .type = NLA_U16 }, 2165 [IFLA_IPTUN_ENCAP_DPORT] = { .type = NLA_U16 }, 2166 [IFLA_IPTUN_COLLECT_METADATA] = { .type = NLA_FLAG }, 2167 [IFLA_IPTUN_FWMARK] = { .type = NLA_U32 }, 2168 }; 2169 2170 static struct rtnl_link_ops ip6_link_ops __read_mostly = { 2171 .kind = "ip6tnl", 2172 .maxtype = IFLA_IPTUN_MAX, 2173 .policy = ip6_tnl_policy, 2174 .priv_size = sizeof(struct ip6_tnl), 2175 .setup = ip6_tnl_dev_setup, 2176 .validate = ip6_tnl_validate, 2177 .newlink = ip6_tnl_newlink, 2178 .changelink = ip6_tnl_changelink, 2179 .dellink = ip6_tnl_dellink, 2180 .get_size = ip6_tnl_get_size, 2181 .fill_info = ip6_tnl_fill_info, 2182 .get_link_net = ip6_tnl_get_link_net, 2183 }; 2184 2185 static struct xfrm6_tunnel ip4ip6_handler __read_mostly = { 2186 .handler = ip4ip6_rcv, 2187 .err_handler = ip4ip6_err, 2188 .priority = 1, 2189 }; 2190 2191 static struct xfrm6_tunnel ip6ip6_handler __read_mostly = { 2192 .handler = ip6ip6_rcv, 2193 .err_handler = ip6ip6_err, 2194 .priority = 1, 2195 }; 2196 2197 static struct xfrm6_tunnel mplsip6_handler __read_mostly = { 2198 .handler = mplsip6_rcv, 2199 .err_handler = mplsip6_err, 2200 .priority = 1, 2201 }; 2202 2203 static void __net_exit ip6_tnl_destroy_tunnels(struct net *net, struct list_head *list) 2204 { 2205 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 2206 struct net_device *dev, *aux; 2207 int h; 2208 struct ip6_tnl *t; 2209 2210 for_each_netdev_safe(net, dev, aux) 2211 if (dev->rtnl_link_ops == &ip6_link_ops) 2212 unregister_netdevice_queue(dev, list); 2213 2214 for (h = 0; h < IP6_TUNNEL_HASH_SIZE; h++) { 2215 t = rtnl_dereference(ip6n->tnls_r_l[h]); 2216 while (t) { 2217 /* If dev is in the same netns, it has already 2218 * been added to the list by the previous loop. 2219 */ 2220 if (!net_eq(dev_net(t->dev), net)) 2221 unregister_netdevice_queue(t->dev, list); 2222 t = rtnl_dereference(t->next); 2223 } 2224 } 2225 2226 t = rtnl_dereference(ip6n->tnls_wc[0]); 2227 while (t) { 2228 /* If dev is in the same netns, it has already 2229 * been added to the list by the previous loop. 2230 */ 2231 if (!net_eq(dev_net(t->dev), net)) 2232 unregister_netdevice_queue(t->dev, list); 2233 t = rtnl_dereference(t->next); 2234 } 2235 } 2236 2237 static int __net_init ip6_tnl_init_net(struct net *net) 2238 { 2239 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 2240 struct ip6_tnl *t = NULL; 2241 int err; 2242 2243 ip6n->tnls[0] = ip6n->tnls_wc; 2244 ip6n->tnls[1] = ip6n->tnls_r_l; 2245 2246 if (!net_has_fallback_tunnels(net)) 2247 return 0; 2248 err = -ENOMEM; 2249 ip6n->fb_tnl_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6tnl0", 2250 NET_NAME_UNKNOWN, ip6_tnl_dev_setup); 2251 2252 if (!ip6n->fb_tnl_dev) 2253 goto err_alloc_dev; 2254 dev_net_set(ip6n->fb_tnl_dev, net); 2255 ip6n->fb_tnl_dev->rtnl_link_ops = &ip6_link_ops; 2256 /* FB netdevice is special: we have one, and only one per netns. 2257 * Allowing to move it to another netns is clearly unsafe. 2258 */ 2259 ip6n->fb_tnl_dev->features |= NETIF_F_NETNS_LOCAL; 2260 2261 err = ip6_fb_tnl_dev_init(ip6n->fb_tnl_dev); 2262 if (err < 0) 2263 goto err_register; 2264 2265 err = register_netdev(ip6n->fb_tnl_dev); 2266 if (err < 0) 2267 goto err_register; 2268 2269 t = netdev_priv(ip6n->fb_tnl_dev); 2270 2271 strcpy(t->parms.name, ip6n->fb_tnl_dev->name); 2272 return 0; 2273 2274 err_register: 2275 free_netdev(ip6n->fb_tnl_dev); 2276 err_alloc_dev: 2277 return err; 2278 } 2279 2280 static void __net_exit ip6_tnl_exit_batch_rtnl(struct list_head *net_list, 2281 struct list_head *dev_to_kill) 2282 { 2283 struct net *net; 2284 2285 ASSERT_RTNL(); 2286 list_for_each_entry(net, net_list, exit_list) 2287 ip6_tnl_destroy_tunnels(net, dev_to_kill); 2288 } 2289 2290 static struct pernet_operations ip6_tnl_net_ops = { 2291 .init = ip6_tnl_init_net, 2292 .exit_batch_rtnl = ip6_tnl_exit_batch_rtnl, 2293 .id = &ip6_tnl_net_id, 2294 .size = sizeof(struct ip6_tnl_net), 2295 }; 2296 2297 /** 2298 * ip6_tunnel_init - register protocol and reserve needed resources 2299 * 2300 * Return: 0 on success 2301 **/ 2302 2303 static int __init ip6_tunnel_init(void) 2304 { 2305 int err; 2306 2307 if (!ipv6_mod_enabled()) 2308 return -EOPNOTSUPP; 2309 2310 err = register_pernet_device(&ip6_tnl_net_ops); 2311 if (err < 0) 2312 goto out_pernet; 2313 2314 err = xfrm6_tunnel_register(&ip4ip6_handler, AF_INET); 2315 if (err < 0) { 2316 pr_err("%s: can't register ip4ip6\n", __func__); 2317 goto out_ip4ip6; 2318 } 2319 2320 err = xfrm6_tunnel_register(&ip6ip6_handler, AF_INET6); 2321 if (err < 0) { 2322 pr_err("%s: can't register ip6ip6\n", __func__); 2323 goto out_ip6ip6; 2324 } 2325 2326 if (ip6_tnl_mpls_supported()) { 2327 err = xfrm6_tunnel_register(&mplsip6_handler, AF_MPLS); 2328 if (err < 0) { 2329 pr_err("%s: can't register mplsip6\n", __func__); 2330 goto out_mplsip6; 2331 } 2332 } 2333 2334 err = rtnl_link_register(&ip6_link_ops); 2335 if (err < 0) 2336 goto rtnl_link_failed; 2337 2338 return 0; 2339 2340 rtnl_link_failed: 2341 if (ip6_tnl_mpls_supported()) 2342 xfrm6_tunnel_deregister(&mplsip6_handler, AF_MPLS); 2343 out_mplsip6: 2344 xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6); 2345 out_ip6ip6: 2346 xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET); 2347 out_ip4ip6: 2348 unregister_pernet_device(&ip6_tnl_net_ops); 2349 out_pernet: 2350 return err; 2351 } 2352 2353 /** 2354 * ip6_tunnel_cleanup - free resources and unregister protocol 2355 **/ 2356 2357 static void __exit ip6_tunnel_cleanup(void) 2358 { 2359 rtnl_link_unregister(&ip6_link_ops); 2360 if (xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET)) 2361 pr_info("%s: can't deregister ip4ip6\n", __func__); 2362 2363 if (xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6)) 2364 pr_info("%s: can't deregister ip6ip6\n", __func__); 2365 2366 if (ip6_tnl_mpls_supported() && 2367 xfrm6_tunnel_deregister(&mplsip6_handler, AF_MPLS)) 2368 pr_info("%s: can't deregister mplsip6\n", __func__); 2369 unregister_pernet_device(&ip6_tnl_net_ops); 2370 } 2371 2372 module_init(ip6_tunnel_init); 2373 module_exit(ip6_tunnel_cleanup); 2374