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 dev->rtnl_link_ops = &ip6_link_ops; 261 err = register_netdevice(dev); 262 if (err < 0) 263 goto out; 264 265 strcpy(t->parms.name, dev->name); 266 267 ip6_tnl_link(ip6n, t); 268 return 0; 269 270 out: 271 return err; 272 } 273 274 /** 275 * ip6_tnl_create - create a new tunnel 276 * @net: network namespace 277 * @p: tunnel parameters 278 * 279 * Description: 280 * Create tunnel matching given parameters. 281 * 282 * Return: 283 * created tunnel or error pointer 284 **/ 285 286 static struct ip6_tnl *ip6_tnl_create(struct net *net, struct __ip6_tnl_parm *p) 287 { 288 struct net_device *dev; 289 struct ip6_tnl *t; 290 char name[IFNAMSIZ]; 291 int err = -E2BIG; 292 293 if (p->name[0]) { 294 if (!dev_valid_name(p->name)) 295 goto failed; 296 strscpy(name, p->name, IFNAMSIZ); 297 } else { 298 sprintf(name, "ip6tnl%%d"); 299 } 300 err = -ENOMEM; 301 dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN, 302 ip6_tnl_dev_setup); 303 if (!dev) 304 goto failed; 305 306 dev_net_set(dev, net); 307 308 t = netdev_priv(dev); 309 t->parms = *p; 310 t->net = dev_net(dev); 311 err = ip6_tnl_create2(dev); 312 if (err < 0) 313 goto failed_free; 314 315 return t; 316 317 failed_free: 318 free_netdev(dev); 319 failed: 320 return ERR_PTR(err); 321 } 322 323 /** 324 * ip6_tnl_locate - find or create tunnel matching given parameters 325 * @net: network namespace 326 * @p: tunnel parameters 327 * @create: != 0 if allowed to create new tunnel if no match found 328 * 329 * Description: 330 * ip6_tnl_locate() first tries to locate an existing tunnel 331 * based on @parms. If this is unsuccessful, but @create is set a new 332 * tunnel device is created and registered for use. 333 * 334 * Return: 335 * matching tunnel or error pointer 336 **/ 337 338 static struct ip6_tnl *ip6_tnl_locate(struct net *net, 339 struct __ip6_tnl_parm *p, int create) 340 { 341 const struct in6_addr *remote = &p->raddr; 342 const struct in6_addr *local = &p->laddr; 343 struct ip6_tnl __rcu **tp; 344 struct ip6_tnl *t; 345 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 346 347 for (tp = ip6_tnl_bucket(ip6n, p); 348 (t = rtnl_dereference(*tp)) != NULL; 349 tp = &t->next) { 350 if (ipv6_addr_equal(local, &t->parms.laddr) && 351 ipv6_addr_equal(remote, &t->parms.raddr) && 352 p->link == t->parms.link) { 353 if (create) 354 return ERR_PTR(-EEXIST); 355 356 return t; 357 } 358 } 359 if (!create) 360 return ERR_PTR(-ENODEV); 361 return ip6_tnl_create(net, p); 362 } 363 364 /** 365 * ip6_tnl_dev_uninit - tunnel device uninitializer 366 * @dev: the device to be destroyed 367 * 368 * Description: 369 * ip6_tnl_dev_uninit() removes tunnel from its list 370 **/ 371 372 static void 373 ip6_tnl_dev_uninit(struct net_device *dev) 374 { 375 struct ip6_tnl *t = netdev_priv(dev); 376 struct net *net = t->net; 377 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 378 379 if (dev == ip6n->fb_tnl_dev) 380 RCU_INIT_POINTER(ip6n->tnls_wc[0], NULL); 381 else 382 ip6_tnl_unlink(ip6n, t); 383 dst_cache_reset(&t->dst_cache); 384 netdev_put(dev, &t->dev_tracker); 385 } 386 387 /** 388 * ip6_tnl_parse_tlv_enc_lim - handle encapsulation limit option 389 * @skb: received socket buffer 390 * @raw: the ICMPv6 error message data 391 * 392 * Return: 393 * 0 if none was found, 394 * else index to encapsulation limit 395 **/ 396 397 __u16 ip6_tnl_parse_tlv_enc_lim(struct sk_buff *skb, __u8 *raw) 398 { 399 const struct ipv6hdr *ipv6h = (const struct ipv6hdr *)raw; 400 unsigned int nhoff = raw - skb->data; 401 unsigned int off = nhoff + sizeof(*ipv6h); 402 u8 nexthdr = ipv6h->nexthdr; 403 404 while (ipv6_ext_hdr(nexthdr) && nexthdr != NEXTHDR_NONE) { 405 struct ipv6_opt_hdr *hdr; 406 u16 optlen; 407 408 if (!pskb_may_pull(skb, off + sizeof(*hdr))) 409 break; 410 411 hdr = (struct ipv6_opt_hdr *)(skb->data + off); 412 if (nexthdr == NEXTHDR_FRAGMENT) { 413 optlen = 8; 414 } else if (nexthdr == NEXTHDR_AUTH) { 415 optlen = ipv6_authlen(hdr); 416 } else { 417 optlen = ipv6_optlen(hdr); 418 } 419 420 if (!pskb_may_pull(skb, off + optlen)) 421 break; 422 423 hdr = (struct ipv6_opt_hdr *)(skb->data + off); 424 if (nexthdr == NEXTHDR_FRAGMENT) { 425 struct frag_hdr *frag_hdr = (struct frag_hdr *)hdr; 426 427 if (frag_hdr->frag_off) 428 break; 429 } 430 if (nexthdr == NEXTHDR_DEST) { 431 u16 i = 2; 432 433 while (1) { 434 struct ipv6_tlv_tnl_enc_lim *tel; 435 436 /* No more room for encapsulation limit */ 437 if (i + sizeof(*tel) > optlen) 438 break; 439 440 tel = (struct ipv6_tlv_tnl_enc_lim *)(skb->data + off + i); 441 /* return index of option if found and valid */ 442 if (tel->type == IPV6_TLV_TNL_ENCAP_LIMIT && 443 tel->length == 1) 444 return i + off - nhoff; 445 /* else jump to next option */ 446 if (tel->type) 447 i += tel->length + 2; 448 else 449 i++; 450 } 451 } 452 nexthdr = hdr->nexthdr; 453 off += optlen; 454 } 455 return 0; 456 } 457 EXPORT_SYMBOL(ip6_tnl_parse_tlv_enc_lim); 458 459 /* ip6_tnl_err() should handle errors in the tunnel according to the 460 * specifications in RFC 2473. 461 */ 462 static int 463 ip6_tnl_err(struct sk_buff *skb, __u8 ipproto, struct inet6_skb_parm *opt, 464 u8 *type, u8 *code, int *msg, __u32 *info, int offset) 465 { 466 const struct ipv6hdr *ipv6h = (const struct ipv6hdr *)skb->data; 467 struct net *net = dev_net(skb->dev); 468 u8 rel_type = ICMPV6_DEST_UNREACH; 469 u8 rel_code = ICMPV6_ADDR_UNREACH; 470 __u32 rel_info = 0; 471 struct ip6_tnl *t; 472 int err = -ENOENT; 473 int rel_msg = 0; 474 u8 tproto; 475 __u16 len; 476 477 /* If the packet doesn't contain the original IPv6 header we are 478 in trouble since we might need the source address for further 479 processing of the error. */ 480 481 rcu_read_lock(); 482 t = ip6_tnl_lookup(dev_net(skb->dev), skb->dev->ifindex, &ipv6h->daddr, &ipv6h->saddr); 483 if (!t) 484 goto out; 485 486 tproto = READ_ONCE(t->parms.proto); 487 if (tproto != ipproto && tproto != 0) 488 goto out; 489 490 err = 0; 491 492 switch (*type) { 493 case ICMPV6_DEST_UNREACH: 494 net_dbg_ratelimited("%s: Path to destination invalid or inactive!\n", 495 t->parms.name); 496 rel_msg = 1; 497 break; 498 case ICMPV6_TIME_EXCEED: 499 if ((*code) == ICMPV6_EXC_HOPLIMIT) { 500 net_dbg_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n", 501 t->parms.name); 502 rel_msg = 1; 503 } 504 break; 505 case ICMPV6_PARAMPROB: { 506 struct ipv6_tlv_tnl_enc_lim *tel; 507 __u32 teli; 508 509 teli = 0; 510 if ((*code) == ICMPV6_HDR_FIELD) 511 teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data); 512 513 if (teli && teli == *info - 2) { 514 tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli]; 515 if (tel->encap_limit == 0) { 516 net_dbg_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n", 517 t->parms.name); 518 rel_msg = 1; 519 } 520 } else { 521 net_dbg_ratelimited("%s: Recipient unable to parse tunneled packet!\n", 522 t->parms.name); 523 } 524 break; 525 } 526 case ICMPV6_PKT_TOOBIG: { 527 __u32 mtu; 528 529 ip6_update_pmtu(skb, net, htonl(*info), 0, 0, 530 sock_net_uid(net, NULL)); 531 mtu = *info - offset; 532 if (mtu < IPV6_MIN_MTU) 533 mtu = IPV6_MIN_MTU; 534 len = sizeof(*ipv6h) + ntohs(ipv6h->payload_len); 535 if (len > mtu) { 536 rel_type = ICMPV6_PKT_TOOBIG; 537 rel_code = 0; 538 rel_info = mtu; 539 rel_msg = 1; 540 } 541 break; 542 } 543 case NDISC_REDIRECT: 544 ip6_redirect(skb, net, skb->dev->ifindex, 0, 545 sock_net_uid(net, NULL)); 546 break; 547 } 548 549 *type = rel_type; 550 *code = rel_code; 551 *info = rel_info; 552 *msg = rel_msg; 553 554 out: 555 rcu_read_unlock(); 556 return err; 557 } 558 559 static int 560 ip4ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 561 u8 type, u8 code, int offset, __be32 info) 562 { 563 __u32 rel_info = ntohl(info); 564 const struct iphdr *eiph; 565 struct sk_buff *skb2; 566 int err, rel_msg = 0; 567 u8 rel_type = type; 568 u8 rel_code = code; 569 struct rtable *rt; 570 struct flowi4 fl4; 571 572 err = ip6_tnl_err(skb, IPPROTO_IPIP, opt, &rel_type, &rel_code, 573 &rel_msg, &rel_info, offset); 574 if (err < 0) 575 return err; 576 577 if (rel_msg == 0) 578 return 0; 579 580 switch (rel_type) { 581 case ICMPV6_DEST_UNREACH: 582 if (rel_code != ICMPV6_ADDR_UNREACH) 583 return 0; 584 rel_type = ICMP_DEST_UNREACH; 585 rel_code = ICMP_HOST_UNREACH; 586 break; 587 case ICMPV6_PKT_TOOBIG: 588 if (rel_code != 0) 589 return 0; 590 rel_type = ICMP_DEST_UNREACH; 591 rel_code = ICMP_FRAG_NEEDED; 592 break; 593 default: 594 return 0; 595 } 596 597 if (!pskb_may_pull(skb, offset + sizeof(struct iphdr))) 598 return 0; 599 600 skb2 = skb_clone(skb, GFP_ATOMIC); 601 if (!skb2) 602 return 0; 603 604 skb_dst_drop(skb2); 605 606 skb_pull(skb2, offset); 607 skb_reset_network_header(skb2); 608 eiph = ip_hdr(skb2); 609 610 /* Try to guess incoming interface */ 611 rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL, eiph->saddr, 612 0, 0, 0, IPPROTO_IPIP, RT_TOS(eiph->tos), 0); 613 if (IS_ERR(rt)) 614 goto out; 615 616 skb2->dev = rt->dst.dev; 617 ip_rt_put(rt); 618 619 /* route "incoming" packet */ 620 if (rt->rt_flags & RTCF_LOCAL) { 621 rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL, 622 eiph->daddr, eiph->saddr, 0, 0, 623 IPPROTO_IPIP, RT_TOS(eiph->tos), 0); 624 if (IS_ERR(rt) || rt->dst.dev->type != ARPHRD_TUNNEL6) { 625 if (!IS_ERR(rt)) 626 ip_rt_put(rt); 627 goto out; 628 } 629 skb_dst_set(skb2, &rt->dst); 630 } else { 631 if (ip_route_input(skb2, eiph->daddr, eiph->saddr, eiph->tos, 632 skb2->dev) || 633 skb_dst(skb2)->dev->type != ARPHRD_TUNNEL6) 634 goto out; 635 } 636 637 /* change mtu on this route */ 638 if (rel_type == ICMP_DEST_UNREACH && rel_code == ICMP_FRAG_NEEDED) { 639 if (rel_info > dst_mtu(skb_dst(skb2))) 640 goto out; 641 642 skb_dst_update_pmtu_no_confirm(skb2, rel_info); 643 } 644 645 icmp_send(skb2, rel_type, rel_code, htonl(rel_info)); 646 647 out: 648 kfree_skb(skb2); 649 return 0; 650 } 651 652 static int 653 ip6ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 654 u8 type, u8 code, int offset, __be32 info) 655 { 656 __u32 rel_info = ntohl(info); 657 int err, rel_msg = 0; 658 u8 rel_type = type; 659 u8 rel_code = code; 660 661 err = ip6_tnl_err(skb, IPPROTO_IPV6, opt, &rel_type, &rel_code, 662 &rel_msg, &rel_info, offset); 663 if (err < 0) 664 return err; 665 666 if (rel_msg && pskb_may_pull(skb, offset + sizeof(struct ipv6hdr))) { 667 struct rt6_info *rt; 668 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC); 669 670 if (!skb2) 671 return 0; 672 673 skb_dst_drop(skb2); 674 skb_pull(skb2, offset); 675 skb_reset_network_header(skb2); 676 677 /* Try to guess incoming interface */ 678 rt = rt6_lookup(dev_net(skb->dev), &ipv6_hdr(skb2)->saddr, 679 NULL, 0, skb2, 0); 680 681 if (rt && rt->dst.dev) 682 skb2->dev = rt->dst.dev; 683 684 icmpv6_send(skb2, rel_type, rel_code, rel_info); 685 686 ip6_rt_put(rt); 687 688 kfree_skb(skb2); 689 } 690 691 return 0; 692 } 693 694 static int 695 mplsip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 696 u8 type, u8 code, int offset, __be32 info) 697 { 698 __u32 rel_info = ntohl(info); 699 int err, rel_msg = 0; 700 u8 rel_type = type; 701 u8 rel_code = code; 702 703 err = ip6_tnl_err(skb, IPPROTO_MPLS, opt, &rel_type, &rel_code, 704 &rel_msg, &rel_info, offset); 705 return err; 706 } 707 708 static int ip4ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t, 709 const struct ipv6hdr *ipv6h, 710 struct sk_buff *skb) 711 { 712 __u8 dsfield = ipv6_get_dsfield(ipv6h) & ~INET_ECN_MASK; 713 714 if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY) 715 ipv4_change_dsfield(ip_hdr(skb), INET_ECN_MASK, dsfield); 716 717 return IP6_ECN_decapsulate(ipv6h, skb); 718 } 719 720 static int ip6ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t, 721 const struct ipv6hdr *ipv6h, 722 struct sk_buff *skb) 723 { 724 if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY) 725 ipv6_copy_dscp(ipv6_get_dsfield(ipv6h), ipv6_hdr(skb)); 726 727 return IP6_ECN_decapsulate(ipv6h, skb); 728 } 729 730 static inline int mplsip6_dscp_ecn_decapsulate(const struct ip6_tnl *t, 731 const struct ipv6hdr *ipv6h, 732 struct sk_buff *skb) 733 { 734 /* ECN is not supported in AF_MPLS */ 735 return 0; 736 } 737 738 __u32 ip6_tnl_get_cap(struct ip6_tnl *t, 739 const struct in6_addr *laddr, 740 const struct in6_addr *raddr) 741 { 742 struct __ip6_tnl_parm *p = &t->parms; 743 int ltype = ipv6_addr_type(laddr); 744 int rtype = ipv6_addr_type(raddr); 745 __u32 flags = 0; 746 747 if (ltype == IPV6_ADDR_ANY || rtype == IPV6_ADDR_ANY) { 748 flags = IP6_TNL_F_CAP_PER_PACKET; 749 } else if (ltype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) && 750 rtype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) && 751 !((ltype|rtype) & IPV6_ADDR_LOOPBACK) && 752 (!((ltype|rtype) & IPV6_ADDR_LINKLOCAL) || p->link)) { 753 if (ltype&IPV6_ADDR_UNICAST) 754 flags |= IP6_TNL_F_CAP_XMIT; 755 if (rtype&IPV6_ADDR_UNICAST) 756 flags |= IP6_TNL_F_CAP_RCV; 757 } 758 return flags; 759 } 760 EXPORT_SYMBOL(ip6_tnl_get_cap); 761 762 /* called with rcu_read_lock() */ 763 int ip6_tnl_rcv_ctl(struct ip6_tnl *t, 764 const struct in6_addr *laddr, 765 const struct in6_addr *raddr) 766 { 767 struct __ip6_tnl_parm *p = &t->parms; 768 int ret = 0; 769 struct net *net = t->net; 770 771 if ((p->flags & IP6_TNL_F_CAP_RCV) || 772 ((p->flags & IP6_TNL_F_CAP_PER_PACKET) && 773 (ip6_tnl_get_cap(t, laddr, raddr) & IP6_TNL_F_CAP_RCV))) { 774 struct net_device *ldev = NULL; 775 776 if (p->link) 777 ldev = dev_get_by_index_rcu(net, p->link); 778 779 if ((ipv6_addr_is_multicast(laddr) || 780 likely(ipv6_chk_addr_and_flags(net, laddr, ldev, false, 781 0, IFA_F_TENTATIVE))) && 782 ((p->flags & IP6_TNL_F_ALLOW_LOCAL_REMOTE) || 783 likely(!ipv6_chk_addr_and_flags(net, raddr, ldev, true, 784 0, IFA_F_TENTATIVE)))) 785 ret = 1; 786 } 787 return ret; 788 } 789 EXPORT_SYMBOL_GPL(ip6_tnl_rcv_ctl); 790 791 static int __ip6_tnl_rcv(struct ip6_tnl *tunnel, struct sk_buff *skb, 792 const struct tnl_ptk_info *tpi, 793 struct metadata_dst *tun_dst, 794 int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t, 795 const struct ipv6hdr *ipv6h, 796 struct sk_buff *skb), 797 bool log_ecn_err) 798 { 799 const struct ipv6hdr *ipv6h; 800 int nh, err; 801 802 if ((!(tpi->flags & TUNNEL_CSUM) && 803 (tunnel->parms.i_flags & TUNNEL_CSUM)) || 804 ((tpi->flags & TUNNEL_CSUM) && 805 !(tunnel->parms.i_flags & TUNNEL_CSUM))) { 806 DEV_STATS_INC(tunnel->dev, rx_crc_errors); 807 DEV_STATS_INC(tunnel->dev, rx_errors); 808 goto drop; 809 } 810 811 if (tunnel->parms.i_flags & TUNNEL_SEQ) { 812 if (!(tpi->flags & TUNNEL_SEQ) || 813 (tunnel->i_seqno && 814 (s32)(ntohl(tpi->seq) - tunnel->i_seqno) < 0)) { 815 DEV_STATS_INC(tunnel->dev, rx_fifo_errors); 816 DEV_STATS_INC(tunnel->dev, rx_errors); 817 goto drop; 818 } 819 tunnel->i_seqno = ntohl(tpi->seq) + 1; 820 } 821 822 skb->protocol = tpi->proto; 823 824 /* Warning: All skb pointers will be invalidated! */ 825 if (tunnel->dev->type == ARPHRD_ETHER) { 826 if (!pskb_may_pull(skb, ETH_HLEN)) { 827 DEV_STATS_INC(tunnel->dev, rx_length_errors); 828 DEV_STATS_INC(tunnel->dev, rx_errors); 829 goto drop; 830 } 831 832 skb->protocol = eth_type_trans(skb, tunnel->dev); 833 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN); 834 } else { 835 skb->dev = tunnel->dev; 836 skb_reset_mac_header(skb); 837 } 838 839 /* Save offset of outer header relative to skb->head, 840 * because we are going to reset the network header to the inner header 841 * and might change skb->head. 842 */ 843 nh = skb_network_header(skb) - skb->head; 844 845 skb_reset_network_header(skb); 846 847 if (!pskb_inet_may_pull(skb)) { 848 DEV_STATS_INC(tunnel->dev, rx_length_errors); 849 DEV_STATS_INC(tunnel->dev, rx_errors); 850 goto drop; 851 } 852 853 /* Get the outer header. */ 854 ipv6h = (struct ipv6hdr *)(skb->head + nh); 855 856 memset(skb->cb, 0, sizeof(struct inet6_skb_parm)); 857 858 __skb_tunnel_rx(skb, tunnel->dev, tunnel->net); 859 860 err = dscp_ecn_decapsulate(tunnel, ipv6h, skb); 861 if (unlikely(err)) { 862 if (log_ecn_err) 863 net_info_ratelimited("non-ECT from %pI6 with DS=%#x\n", 864 &ipv6h->saddr, 865 ipv6_get_dsfield(ipv6h)); 866 if (err > 1) { 867 DEV_STATS_INC(tunnel->dev, rx_frame_errors); 868 DEV_STATS_INC(tunnel->dev, rx_errors); 869 goto drop; 870 } 871 } 872 873 dev_sw_netstats_rx_add(tunnel->dev, skb->len); 874 875 skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(tunnel->dev))); 876 877 if (tun_dst) 878 skb_dst_set(skb, (struct dst_entry *)tun_dst); 879 880 gro_cells_receive(&tunnel->gro_cells, skb); 881 return 0; 882 883 drop: 884 if (tun_dst) 885 dst_release((struct dst_entry *)tun_dst); 886 kfree_skb(skb); 887 return 0; 888 } 889 890 int ip6_tnl_rcv(struct ip6_tnl *t, struct sk_buff *skb, 891 const struct tnl_ptk_info *tpi, 892 struct metadata_dst *tun_dst, 893 bool log_ecn_err) 894 { 895 int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t, 896 const struct ipv6hdr *ipv6h, 897 struct sk_buff *skb); 898 899 dscp_ecn_decapsulate = ip6ip6_dscp_ecn_decapsulate; 900 if (tpi->proto == htons(ETH_P_IP)) 901 dscp_ecn_decapsulate = ip4ip6_dscp_ecn_decapsulate; 902 903 return __ip6_tnl_rcv(t, skb, tpi, tun_dst, dscp_ecn_decapsulate, 904 log_ecn_err); 905 } 906 EXPORT_SYMBOL(ip6_tnl_rcv); 907 908 static const struct tnl_ptk_info tpi_v6 = { 909 /* no tunnel info required for ipxip6. */ 910 .proto = htons(ETH_P_IPV6), 911 }; 912 913 static const struct tnl_ptk_info tpi_v4 = { 914 /* no tunnel info required for ipxip6. */ 915 .proto = htons(ETH_P_IP), 916 }; 917 918 static const struct tnl_ptk_info tpi_mpls = { 919 /* no tunnel info required for mplsip6. */ 920 .proto = htons(ETH_P_MPLS_UC), 921 }; 922 923 static int ipxip6_rcv(struct sk_buff *skb, u8 ipproto, 924 const struct tnl_ptk_info *tpi, 925 int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t, 926 const struct ipv6hdr *ipv6h, 927 struct sk_buff *skb)) 928 { 929 struct ip6_tnl *t; 930 const struct ipv6hdr *ipv6h = ipv6_hdr(skb); 931 struct metadata_dst *tun_dst = NULL; 932 int ret = -1; 933 934 rcu_read_lock(); 935 t = ip6_tnl_lookup(dev_net(skb->dev), skb->dev->ifindex, &ipv6h->saddr, &ipv6h->daddr); 936 937 if (t) { 938 u8 tproto = READ_ONCE(t->parms.proto); 939 940 if (tproto != ipproto && tproto != 0) 941 goto drop; 942 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) 943 goto drop; 944 ipv6h = ipv6_hdr(skb); 945 if (!ip6_tnl_rcv_ctl(t, &ipv6h->daddr, &ipv6h->saddr)) 946 goto drop; 947 if (iptunnel_pull_header(skb, 0, tpi->proto, false)) 948 goto drop; 949 if (t->parms.collect_md) { 950 tun_dst = ipv6_tun_rx_dst(skb, 0, 0, 0); 951 if (!tun_dst) 952 goto drop; 953 } 954 ret = __ip6_tnl_rcv(t, skb, tpi, tun_dst, dscp_ecn_decapsulate, 955 log_ecn_error); 956 } 957 958 rcu_read_unlock(); 959 960 return ret; 961 962 drop: 963 rcu_read_unlock(); 964 kfree_skb(skb); 965 return 0; 966 } 967 968 static int ip4ip6_rcv(struct sk_buff *skb) 969 { 970 return ipxip6_rcv(skb, IPPROTO_IPIP, &tpi_v4, 971 ip4ip6_dscp_ecn_decapsulate); 972 } 973 974 static int ip6ip6_rcv(struct sk_buff *skb) 975 { 976 return ipxip6_rcv(skb, IPPROTO_IPV6, &tpi_v6, 977 ip6ip6_dscp_ecn_decapsulate); 978 } 979 980 static int mplsip6_rcv(struct sk_buff *skb) 981 { 982 return ipxip6_rcv(skb, IPPROTO_MPLS, &tpi_mpls, 983 mplsip6_dscp_ecn_decapsulate); 984 } 985 986 struct ipv6_tel_txoption { 987 struct ipv6_txoptions ops; 988 __u8 dst_opt[8]; 989 }; 990 991 static void init_tel_txopt(struct ipv6_tel_txoption *opt, __u8 encap_limit) 992 { 993 memset(opt, 0, sizeof(struct ipv6_tel_txoption)); 994 995 opt->dst_opt[2] = IPV6_TLV_TNL_ENCAP_LIMIT; 996 opt->dst_opt[3] = 1; 997 opt->dst_opt[4] = encap_limit; 998 opt->dst_opt[5] = IPV6_TLV_PADN; 999 opt->dst_opt[6] = 1; 1000 1001 opt->ops.dst1opt = (struct ipv6_opt_hdr *) opt->dst_opt; 1002 opt->ops.opt_nflen = 8; 1003 } 1004 1005 /** 1006 * ip6_tnl_addr_conflict - compare packet addresses to tunnel's own 1007 * @t: the outgoing tunnel device 1008 * @hdr: IPv6 header from the incoming packet 1009 * 1010 * Description: 1011 * Avoid trivial tunneling loop by checking that tunnel exit-point 1012 * doesn't match source of incoming packet. 1013 * 1014 * Return: 1015 * 1 if conflict, 1016 * 0 else 1017 **/ 1018 1019 static inline bool 1020 ip6_tnl_addr_conflict(const struct ip6_tnl *t, const struct ipv6hdr *hdr) 1021 { 1022 return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr); 1023 } 1024 1025 int ip6_tnl_xmit_ctl(struct ip6_tnl *t, 1026 const struct in6_addr *laddr, 1027 const struct in6_addr *raddr) 1028 { 1029 struct __ip6_tnl_parm *p = &t->parms; 1030 int ret = 0; 1031 struct net *net = t->net; 1032 1033 if (t->parms.collect_md) 1034 return 1; 1035 1036 if ((p->flags & IP6_TNL_F_CAP_XMIT) || 1037 ((p->flags & IP6_TNL_F_CAP_PER_PACKET) && 1038 (ip6_tnl_get_cap(t, laddr, raddr) & IP6_TNL_F_CAP_XMIT))) { 1039 struct net_device *ldev = NULL; 1040 1041 rcu_read_lock(); 1042 if (p->link) 1043 ldev = dev_get_by_index_rcu(net, p->link); 1044 1045 if (unlikely(!ipv6_chk_addr_and_flags(net, laddr, ldev, false, 1046 0, IFA_F_TENTATIVE))) 1047 pr_warn_ratelimited("%s xmit: Local address not yet configured!\n", 1048 p->name); 1049 else if (!(p->flags & IP6_TNL_F_ALLOW_LOCAL_REMOTE) && 1050 !ipv6_addr_is_multicast(raddr) && 1051 unlikely(ipv6_chk_addr_and_flags(net, raddr, ldev, 1052 true, 0, IFA_F_TENTATIVE))) 1053 pr_warn_ratelimited("%s xmit: Routing loop! Remote address found on this node!\n", 1054 p->name); 1055 else 1056 ret = 1; 1057 rcu_read_unlock(); 1058 } 1059 return ret; 1060 } 1061 EXPORT_SYMBOL_GPL(ip6_tnl_xmit_ctl); 1062 1063 /** 1064 * ip6_tnl_xmit - encapsulate packet and send 1065 * @skb: the outgoing socket buffer 1066 * @dev: the outgoing tunnel device 1067 * @dsfield: dscp code for outer header 1068 * @fl6: flow of tunneled packet 1069 * @encap_limit: encapsulation limit 1070 * @pmtu: Path MTU is stored if packet is too big 1071 * @proto: next header value 1072 * 1073 * Description: 1074 * Build new header and do some sanity checks on the packet before sending 1075 * it. 1076 * 1077 * Return: 1078 * 0 on success 1079 * -1 fail 1080 * %-EMSGSIZE message too big. return mtu in this case. 1081 **/ 1082 1083 int ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev, __u8 dsfield, 1084 struct flowi6 *fl6, int encap_limit, __u32 *pmtu, 1085 __u8 proto) 1086 { 1087 struct ip6_tnl *t = netdev_priv(dev); 1088 struct net *net = t->net; 1089 struct ipv6hdr *ipv6h; 1090 struct ipv6_tel_txoption opt; 1091 struct dst_entry *dst = NULL, *ndst = NULL; 1092 struct net_device *tdev; 1093 int mtu; 1094 unsigned int eth_hlen = t->dev->type == ARPHRD_ETHER ? ETH_HLEN : 0; 1095 unsigned int psh_hlen = sizeof(struct ipv6hdr) + t->encap_hlen; 1096 unsigned int max_headroom = psh_hlen; 1097 __be16 payload_protocol; 1098 bool use_cache = false; 1099 u8 hop_limit; 1100 int err = -1; 1101 1102 payload_protocol = skb_protocol(skb, true); 1103 1104 if (t->parms.collect_md) { 1105 hop_limit = skb_tunnel_info(skb)->key.ttl; 1106 goto route_lookup; 1107 } else { 1108 hop_limit = t->parms.hop_limit; 1109 } 1110 1111 /* NBMA tunnel */ 1112 if (ipv6_addr_any(&t->parms.raddr)) { 1113 if (payload_protocol == htons(ETH_P_IPV6)) { 1114 struct in6_addr *addr6; 1115 struct neighbour *neigh; 1116 int addr_type; 1117 1118 if (!skb_dst(skb)) 1119 goto tx_err_link_failure; 1120 1121 neigh = dst_neigh_lookup(skb_dst(skb), 1122 &ipv6_hdr(skb)->daddr); 1123 if (!neigh) 1124 goto tx_err_link_failure; 1125 1126 addr6 = (struct in6_addr *)&neigh->primary_key; 1127 addr_type = ipv6_addr_type(addr6); 1128 1129 if (addr_type == IPV6_ADDR_ANY) 1130 addr6 = &ipv6_hdr(skb)->daddr; 1131 1132 memcpy(&fl6->daddr, addr6, sizeof(fl6->daddr)); 1133 neigh_release(neigh); 1134 } else if (payload_protocol == htons(ETH_P_IP)) { 1135 const struct rtable *rt = skb_rtable(skb); 1136 1137 if (!rt) 1138 goto tx_err_link_failure; 1139 1140 if (rt->rt_gw_family == AF_INET6) 1141 memcpy(&fl6->daddr, &rt->rt_gw6, sizeof(fl6->daddr)); 1142 } 1143 } else if (t->parms.proto != 0 && !(t->parms.flags & 1144 (IP6_TNL_F_USE_ORIG_TCLASS | 1145 IP6_TNL_F_USE_ORIG_FWMARK))) { 1146 /* enable the cache only if neither the outer protocol nor the 1147 * routing decision depends on the current inner header value 1148 */ 1149 use_cache = true; 1150 } 1151 1152 if (use_cache) 1153 dst = dst_cache_get(&t->dst_cache); 1154 1155 if (!ip6_tnl_xmit_ctl(t, &fl6->saddr, &fl6->daddr)) 1156 goto tx_err_link_failure; 1157 1158 if (!dst) { 1159 route_lookup: 1160 /* add dsfield to flowlabel for route lookup */ 1161 fl6->flowlabel = ip6_make_flowinfo(dsfield, fl6->flowlabel); 1162 1163 dst = ip6_route_output(net, NULL, fl6); 1164 1165 if (dst->error) 1166 goto tx_err_link_failure; 1167 dst = xfrm_lookup(net, dst, flowi6_to_flowi(fl6), NULL, 0); 1168 if (IS_ERR(dst)) { 1169 err = PTR_ERR(dst); 1170 dst = NULL; 1171 goto tx_err_link_failure; 1172 } 1173 if (t->parms.collect_md && ipv6_addr_any(&fl6->saddr) && 1174 ipv6_dev_get_saddr(net, ip6_dst_idev(dst)->dev, 1175 &fl6->daddr, 0, &fl6->saddr)) 1176 goto tx_err_link_failure; 1177 ndst = dst; 1178 } 1179 1180 tdev = dst->dev; 1181 1182 if (tdev == dev) { 1183 DEV_STATS_INC(dev, collisions); 1184 net_warn_ratelimited("%s: Local routing loop detected!\n", 1185 t->parms.name); 1186 goto tx_err_dst_release; 1187 } 1188 mtu = dst_mtu(dst) - eth_hlen - psh_hlen - t->tun_hlen; 1189 if (encap_limit >= 0) { 1190 max_headroom += 8; 1191 mtu -= 8; 1192 } 1193 mtu = max(mtu, skb->protocol == htons(ETH_P_IPV6) ? 1194 IPV6_MIN_MTU : IPV4_MIN_MTU); 1195 1196 skb_dst_update_pmtu_no_confirm(skb, mtu); 1197 if (skb->len - t->tun_hlen - eth_hlen > mtu && !skb_is_gso(skb)) { 1198 *pmtu = mtu; 1199 err = -EMSGSIZE; 1200 goto tx_err_dst_release; 1201 } 1202 1203 if (t->err_count > 0) { 1204 if (time_before(jiffies, 1205 t->err_time + IP6TUNNEL_ERR_TIMEO)) { 1206 t->err_count--; 1207 1208 dst_link_failure(skb); 1209 } else { 1210 t->err_count = 0; 1211 } 1212 } 1213 1214 skb_scrub_packet(skb, !net_eq(t->net, dev_net(dev))); 1215 1216 /* 1217 * Okay, now see if we can stuff it in the buffer as-is. 1218 */ 1219 max_headroom += LL_RESERVED_SPACE(tdev); 1220 1221 if (skb_headroom(skb) < max_headroom || skb_shared(skb) || 1222 (skb_cloned(skb) && !skb_clone_writable(skb, 0))) { 1223 struct sk_buff *new_skb; 1224 1225 new_skb = skb_realloc_headroom(skb, max_headroom); 1226 if (!new_skb) 1227 goto tx_err_dst_release; 1228 1229 if (skb->sk) 1230 skb_set_owner_w(new_skb, skb->sk); 1231 consume_skb(skb); 1232 skb = new_skb; 1233 } 1234 1235 if (t->parms.collect_md) { 1236 if (t->encap.type != TUNNEL_ENCAP_NONE) 1237 goto tx_err_dst_release; 1238 } else { 1239 if (use_cache && ndst) 1240 dst_cache_set_ip6(&t->dst_cache, ndst, &fl6->saddr); 1241 } 1242 skb_dst_set(skb, dst); 1243 1244 if (hop_limit == 0) { 1245 if (payload_protocol == htons(ETH_P_IP)) 1246 hop_limit = ip_hdr(skb)->ttl; 1247 else if (payload_protocol == htons(ETH_P_IPV6)) 1248 hop_limit = ipv6_hdr(skb)->hop_limit; 1249 else 1250 hop_limit = ip6_dst_hoplimit(dst); 1251 } 1252 1253 /* Calculate max headroom for all the headers and adjust 1254 * needed_headroom if necessary. 1255 */ 1256 max_headroom = LL_RESERVED_SPACE(dst->dev) + sizeof(struct ipv6hdr) 1257 + dst->header_len + t->hlen; 1258 if (max_headroom > READ_ONCE(dev->needed_headroom)) 1259 WRITE_ONCE(dev->needed_headroom, max_headroom); 1260 1261 err = ip6_tnl_encap(skb, t, &proto, fl6); 1262 if (err) 1263 return err; 1264 1265 if (encap_limit >= 0) { 1266 init_tel_txopt(&opt, encap_limit); 1267 ipv6_push_frag_opts(skb, &opt.ops, &proto); 1268 } 1269 1270 skb_push(skb, sizeof(struct ipv6hdr)); 1271 skb_reset_network_header(skb); 1272 ipv6h = ipv6_hdr(skb); 1273 ip6_flow_hdr(ipv6h, dsfield, 1274 ip6_make_flowlabel(net, skb, fl6->flowlabel, true, fl6)); 1275 ipv6h->hop_limit = hop_limit; 1276 ipv6h->nexthdr = proto; 1277 ipv6h->saddr = fl6->saddr; 1278 ipv6h->daddr = fl6->daddr; 1279 ip6tunnel_xmit(NULL, skb, dev); 1280 return 0; 1281 tx_err_link_failure: 1282 DEV_STATS_INC(dev, tx_carrier_errors); 1283 dst_link_failure(skb); 1284 tx_err_dst_release: 1285 dst_release(dst); 1286 return err; 1287 } 1288 EXPORT_SYMBOL(ip6_tnl_xmit); 1289 1290 static inline int 1291 ipxip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev, 1292 u8 protocol) 1293 { 1294 struct ip6_tnl *t = netdev_priv(dev); 1295 struct ipv6hdr *ipv6h; 1296 const struct iphdr *iph; 1297 int encap_limit = -1; 1298 __u16 offset; 1299 struct flowi6 fl6; 1300 __u8 dsfield, orig_dsfield; 1301 __u32 mtu; 1302 u8 tproto; 1303 int err; 1304 1305 tproto = READ_ONCE(t->parms.proto); 1306 if (tproto != protocol && tproto != 0) 1307 return -1; 1308 1309 if (t->parms.collect_md) { 1310 struct ip_tunnel_info *tun_info; 1311 const struct ip_tunnel_key *key; 1312 1313 tun_info = skb_tunnel_info(skb); 1314 if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) || 1315 ip_tunnel_info_af(tun_info) != AF_INET6)) 1316 return -1; 1317 key = &tun_info->key; 1318 memset(&fl6, 0, sizeof(fl6)); 1319 fl6.flowi6_proto = protocol; 1320 fl6.saddr = key->u.ipv6.src; 1321 fl6.daddr = key->u.ipv6.dst; 1322 fl6.flowlabel = key->label; 1323 dsfield = key->tos; 1324 switch (protocol) { 1325 case IPPROTO_IPIP: 1326 iph = ip_hdr(skb); 1327 orig_dsfield = ipv4_get_dsfield(iph); 1328 break; 1329 case IPPROTO_IPV6: 1330 ipv6h = ipv6_hdr(skb); 1331 orig_dsfield = ipv6_get_dsfield(ipv6h); 1332 break; 1333 default: 1334 orig_dsfield = dsfield; 1335 break; 1336 } 1337 } else { 1338 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1339 encap_limit = t->parms.encap_limit; 1340 if (protocol == IPPROTO_IPV6) { 1341 offset = ip6_tnl_parse_tlv_enc_lim(skb, 1342 skb_network_header(skb)); 1343 /* ip6_tnl_parse_tlv_enc_lim() might have 1344 * reallocated skb->head 1345 */ 1346 if (offset > 0) { 1347 struct ipv6_tlv_tnl_enc_lim *tel; 1348 1349 tel = (void *)&skb_network_header(skb)[offset]; 1350 if (tel->encap_limit == 0) { 1351 icmpv6_ndo_send(skb, ICMPV6_PARAMPROB, 1352 ICMPV6_HDR_FIELD, offset + 2); 1353 return -1; 1354 } 1355 encap_limit = tel->encap_limit - 1; 1356 } 1357 } 1358 1359 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 1360 fl6.flowi6_proto = protocol; 1361 1362 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK) 1363 fl6.flowi6_mark = skb->mark; 1364 else 1365 fl6.flowi6_mark = t->parms.fwmark; 1366 switch (protocol) { 1367 case IPPROTO_IPIP: 1368 iph = ip_hdr(skb); 1369 orig_dsfield = ipv4_get_dsfield(iph); 1370 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) 1371 dsfield = orig_dsfield; 1372 else 1373 dsfield = ip6_tclass(t->parms.flowinfo); 1374 break; 1375 case IPPROTO_IPV6: 1376 ipv6h = ipv6_hdr(skb); 1377 orig_dsfield = ipv6_get_dsfield(ipv6h); 1378 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) 1379 dsfield = orig_dsfield; 1380 else 1381 dsfield = ip6_tclass(t->parms.flowinfo); 1382 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL) 1383 fl6.flowlabel |= ip6_flowlabel(ipv6h); 1384 break; 1385 default: 1386 orig_dsfield = dsfield = ip6_tclass(t->parms.flowinfo); 1387 break; 1388 } 1389 } 1390 1391 fl6.flowi6_uid = sock_net_uid(dev_net(dev), NULL); 1392 dsfield = INET_ECN_encapsulate(dsfield, orig_dsfield); 1393 1394 if (iptunnel_handle_offloads(skb, SKB_GSO_IPXIP6)) 1395 return -1; 1396 1397 skb_set_inner_ipproto(skb, protocol); 1398 1399 err = ip6_tnl_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu, 1400 protocol); 1401 if (err != 0) { 1402 /* XXX: send ICMP error even if DF is not set. */ 1403 if (err == -EMSGSIZE) 1404 switch (protocol) { 1405 case IPPROTO_IPIP: 1406 icmp_ndo_send(skb, ICMP_DEST_UNREACH, 1407 ICMP_FRAG_NEEDED, htonl(mtu)); 1408 break; 1409 case IPPROTO_IPV6: 1410 icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); 1411 break; 1412 default: 1413 break; 1414 } 1415 return -1; 1416 } 1417 1418 return 0; 1419 } 1420 1421 static netdev_tx_t 1422 ip6_tnl_start_xmit(struct sk_buff *skb, struct net_device *dev) 1423 { 1424 struct ip6_tnl *t = netdev_priv(dev); 1425 u8 ipproto; 1426 int ret; 1427 1428 if (!pskb_inet_may_pull(skb)) 1429 goto tx_err; 1430 1431 switch (skb->protocol) { 1432 case htons(ETH_P_IP): 1433 ipproto = IPPROTO_IPIP; 1434 break; 1435 case htons(ETH_P_IPV6): 1436 if (ip6_tnl_addr_conflict(t, ipv6_hdr(skb))) 1437 goto tx_err; 1438 ipproto = IPPROTO_IPV6; 1439 break; 1440 case htons(ETH_P_MPLS_UC): 1441 ipproto = IPPROTO_MPLS; 1442 break; 1443 default: 1444 goto tx_err; 1445 } 1446 1447 ret = ipxip6_tnl_xmit(skb, dev, ipproto); 1448 if (ret < 0) 1449 goto tx_err; 1450 1451 return NETDEV_TX_OK; 1452 1453 tx_err: 1454 DEV_STATS_INC(dev, tx_errors); 1455 DEV_STATS_INC(dev, tx_dropped); 1456 kfree_skb(skb); 1457 return NETDEV_TX_OK; 1458 } 1459 1460 static void ip6_tnl_link_config(struct ip6_tnl *t) 1461 { 1462 struct net_device *dev = t->dev; 1463 struct net_device *tdev = NULL; 1464 struct __ip6_tnl_parm *p = &t->parms; 1465 struct flowi6 *fl6 = &t->fl.u.ip6; 1466 int t_hlen; 1467 int mtu; 1468 1469 __dev_addr_set(dev, &p->laddr, sizeof(struct in6_addr)); 1470 memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr)); 1471 1472 /* Set up flowi template */ 1473 fl6->saddr = p->laddr; 1474 fl6->daddr = p->raddr; 1475 fl6->flowi6_oif = p->link; 1476 fl6->flowlabel = 0; 1477 1478 if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS)) 1479 fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo; 1480 if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL)) 1481 fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo; 1482 1483 p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET); 1484 p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr); 1485 1486 if (p->flags&IP6_TNL_F_CAP_XMIT && p->flags&IP6_TNL_F_CAP_RCV) 1487 dev->flags |= IFF_POINTOPOINT; 1488 else 1489 dev->flags &= ~IFF_POINTOPOINT; 1490 1491 t->tun_hlen = 0; 1492 t->hlen = t->encap_hlen + t->tun_hlen; 1493 t_hlen = t->hlen + sizeof(struct ipv6hdr); 1494 1495 if (p->flags & IP6_TNL_F_CAP_XMIT) { 1496 int strict = (ipv6_addr_type(&p->raddr) & 1497 (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL)); 1498 1499 struct rt6_info *rt = rt6_lookup(t->net, 1500 &p->raddr, &p->laddr, 1501 p->link, NULL, strict); 1502 if (rt) { 1503 tdev = rt->dst.dev; 1504 ip6_rt_put(rt); 1505 } 1506 1507 if (!tdev && p->link) 1508 tdev = __dev_get_by_index(t->net, p->link); 1509 1510 if (tdev) { 1511 dev->needed_headroom = tdev->hard_header_len + 1512 tdev->needed_headroom + t_hlen; 1513 mtu = min_t(unsigned int, tdev->mtu, IP6_MAX_MTU); 1514 1515 mtu = mtu - t_hlen; 1516 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1517 mtu -= 8; 1518 1519 if (mtu < IPV6_MIN_MTU) 1520 mtu = IPV6_MIN_MTU; 1521 WRITE_ONCE(dev->mtu, mtu); 1522 } 1523 } 1524 } 1525 1526 /** 1527 * ip6_tnl_change - update the tunnel parameters 1528 * @t: tunnel to be changed 1529 * @p: tunnel configuration parameters 1530 * 1531 * Description: 1532 * ip6_tnl_change() updates the tunnel parameters 1533 **/ 1534 1535 static void 1536 ip6_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p) 1537 { 1538 t->parms.laddr = p->laddr; 1539 t->parms.raddr = p->raddr; 1540 t->parms.flags = p->flags; 1541 t->parms.hop_limit = p->hop_limit; 1542 t->parms.encap_limit = p->encap_limit; 1543 t->parms.flowinfo = p->flowinfo; 1544 t->parms.link = p->link; 1545 t->parms.proto = p->proto; 1546 t->parms.fwmark = p->fwmark; 1547 dst_cache_reset(&t->dst_cache); 1548 ip6_tnl_link_config(t); 1549 } 1550 1551 static void ip6_tnl_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p) 1552 { 1553 struct net *net = t->net; 1554 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1555 1556 ip6_tnl_unlink(ip6n, t); 1557 synchronize_net(); 1558 ip6_tnl_change(t, p); 1559 ip6_tnl_link(ip6n, t); 1560 netdev_state_change(t->dev); 1561 } 1562 1563 static void ip6_tnl0_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p) 1564 { 1565 /* for default tnl0 device allow to change only the proto */ 1566 t->parms.proto = p->proto; 1567 netdev_state_change(t->dev); 1568 } 1569 1570 static void 1571 ip6_tnl_parm_from_user(struct __ip6_tnl_parm *p, const struct ip6_tnl_parm *u) 1572 { 1573 p->laddr = u->laddr; 1574 p->raddr = u->raddr; 1575 p->flags = u->flags; 1576 p->hop_limit = u->hop_limit; 1577 p->encap_limit = u->encap_limit; 1578 p->flowinfo = u->flowinfo; 1579 p->link = u->link; 1580 p->proto = u->proto; 1581 memcpy(p->name, u->name, sizeof(u->name)); 1582 } 1583 1584 static void 1585 ip6_tnl_parm_to_user(struct ip6_tnl_parm *u, const struct __ip6_tnl_parm *p) 1586 { 1587 u->laddr = p->laddr; 1588 u->raddr = p->raddr; 1589 u->flags = p->flags; 1590 u->hop_limit = p->hop_limit; 1591 u->encap_limit = p->encap_limit; 1592 u->flowinfo = p->flowinfo; 1593 u->link = p->link; 1594 u->proto = p->proto; 1595 memcpy(u->name, p->name, sizeof(u->name)); 1596 } 1597 1598 /** 1599 * ip6_tnl_siocdevprivate - configure ipv6 tunnels from userspace 1600 * @dev: virtual device associated with tunnel 1601 * @ifr: unused 1602 * @data: parameters passed from userspace 1603 * @cmd: command to be performed 1604 * 1605 * Description: 1606 * ip6_tnl_ioctl() is used for managing IPv6 tunnels 1607 * from userspace. 1608 * 1609 * The possible commands are the following: 1610 * %SIOCGETTUNNEL: get tunnel parameters for device 1611 * %SIOCADDTUNNEL: add tunnel matching given tunnel parameters 1612 * %SIOCCHGTUNNEL: change tunnel parameters to those given 1613 * %SIOCDELTUNNEL: delete tunnel 1614 * 1615 * The fallback device "ip6tnl0", created during module 1616 * initialization, can be used for creating other tunnel devices. 1617 * 1618 * Return: 1619 * 0 on success, 1620 * %-EFAULT if unable to copy data to or from userspace, 1621 * %-EPERM if current process hasn't %CAP_NET_ADMIN set 1622 * %-EINVAL if passed tunnel parameters are invalid, 1623 * %-EEXIST if changing a tunnel's parameters would cause a conflict 1624 * %-ENODEV if attempting to change or delete a nonexisting device 1625 **/ 1626 1627 static int 1628 ip6_tnl_siocdevprivate(struct net_device *dev, struct ifreq *ifr, 1629 void __user *data, int cmd) 1630 { 1631 int err = 0; 1632 struct ip6_tnl_parm p; 1633 struct __ip6_tnl_parm p1; 1634 struct ip6_tnl *t = netdev_priv(dev); 1635 struct net *net = t->net; 1636 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1637 1638 memset(&p1, 0, sizeof(p1)); 1639 1640 switch (cmd) { 1641 case SIOCGETTUNNEL: 1642 if (dev == ip6n->fb_tnl_dev) { 1643 if (copy_from_user(&p, data, sizeof(p))) { 1644 err = -EFAULT; 1645 break; 1646 } 1647 ip6_tnl_parm_from_user(&p1, &p); 1648 t = ip6_tnl_locate(net, &p1, 0); 1649 if (IS_ERR(t)) 1650 t = netdev_priv(dev); 1651 } else { 1652 memset(&p, 0, sizeof(p)); 1653 } 1654 ip6_tnl_parm_to_user(&p, &t->parms); 1655 if (copy_to_user(data, &p, sizeof(p))) 1656 err = -EFAULT; 1657 break; 1658 case SIOCADDTUNNEL: 1659 case SIOCCHGTUNNEL: 1660 err = -EPERM; 1661 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 1662 break; 1663 err = -EFAULT; 1664 if (copy_from_user(&p, data, sizeof(p))) 1665 break; 1666 err = -EINVAL; 1667 if (p.proto != IPPROTO_IPV6 && p.proto != IPPROTO_IPIP && 1668 p.proto != 0) 1669 break; 1670 ip6_tnl_parm_from_user(&p1, &p); 1671 t = ip6_tnl_locate(net, &p1, cmd == SIOCADDTUNNEL); 1672 if (cmd == SIOCCHGTUNNEL) { 1673 if (!IS_ERR(t)) { 1674 if (t->dev != dev) { 1675 err = -EEXIST; 1676 break; 1677 } 1678 } else 1679 t = netdev_priv(dev); 1680 if (dev == ip6n->fb_tnl_dev) 1681 ip6_tnl0_update(t, &p1); 1682 else 1683 ip6_tnl_update(t, &p1); 1684 } 1685 if (!IS_ERR(t)) { 1686 err = 0; 1687 ip6_tnl_parm_to_user(&p, &t->parms); 1688 if (copy_to_user(data, &p, sizeof(p))) 1689 err = -EFAULT; 1690 1691 } else { 1692 err = PTR_ERR(t); 1693 } 1694 break; 1695 case SIOCDELTUNNEL: 1696 err = -EPERM; 1697 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 1698 break; 1699 1700 if (dev == ip6n->fb_tnl_dev) { 1701 err = -EFAULT; 1702 if (copy_from_user(&p, data, sizeof(p))) 1703 break; 1704 err = -ENOENT; 1705 ip6_tnl_parm_from_user(&p1, &p); 1706 t = ip6_tnl_locate(net, &p1, 0); 1707 if (IS_ERR(t)) 1708 break; 1709 err = -EPERM; 1710 if (t->dev == ip6n->fb_tnl_dev) 1711 break; 1712 dev = t->dev; 1713 } 1714 err = 0; 1715 unregister_netdevice(dev); 1716 break; 1717 default: 1718 err = -EINVAL; 1719 } 1720 return err; 1721 } 1722 1723 /** 1724 * ip6_tnl_change_mtu - change mtu manually for tunnel device 1725 * @dev: virtual device associated with tunnel 1726 * @new_mtu: the new mtu 1727 * 1728 * Return: 1729 * 0 on success, 1730 * %-EINVAL if mtu too small 1731 **/ 1732 1733 int ip6_tnl_change_mtu(struct net_device *dev, int new_mtu) 1734 { 1735 struct ip6_tnl *tnl = netdev_priv(dev); 1736 int t_hlen; 1737 1738 t_hlen = tnl->hlen + sizeof(struct ipv6hdr); 1739 if (tnl->parms.proto == IPPROTO_IPV6) { 1740 if (new_mtu < IPV6_MIN_MTU) 1741 return -EINVAL; 1742 } else { 1743 if (new_mtu < ETH_MIN_MTU) 1744 return -EINVAL; 1745 } 1746 if (tnl->parms.proto == IPPROTO_IPV6 || tnl->parms.proto == 0) { 1747 if (new_mtu > IP6_MAX_MTU - dev->hard_header_len - t_hlen) 1748 return -EINVAL; 1749 } else { 1750 if (new_mtu > IP_MAX_MTU - dev->hard_header_len - t_hlen) 1751 return -EINVAL; 1752 } 1753 dev->mtu = new_mtu; 1754 return 0; 1755 } 1756 EXPORT_SYMBOL(ip6_tnl_change_mtu); 1757 1758 int ip6_tnl_get_iflink(const struct net_device *dev) 1759 { 1760 struct ip6_tnl *t = netdev_priv(dev); 1761 1762 return t->parms.link; 1763 } 1764 EXPORT_SYMBOL(ip6_tnl_get_iflink); 1765 1766 int ip6_tnl_encap_add_ops(const struct ip6_tnl_encap_ops *ops, 1767 unsigned int num) 1768 { 1769 if (num >= MAX_IPTUN_ENCAP_OPS) 1770 return -ERANGE; 1771 1772 return !cmpxchg((const struct ip6_tnl_encap_ops **) 1773 &ip6tun_encaps[num], 1774 NULL, ops) ? 0 : -1; 1775 } 1776 EXPORT_SYMBOL(ip6_tnl_encap_add_ops); 1777 1778 int ip6_tnl_encap_del_ops(const struct ip6_tnl_encap_ops *ops, 1779 unsigned int num) 1780 { 1781 int ret; 1782 1783 if (num >= MAX_IPTUN_ENCAP_OPS) 1784 return -ERANGE; 1785 1786 ret = (cmpxchg((const struct ip6_tnl_encap_ops **) 1787 &ip6tun_encaps[num], 1788 ops, NULL) == ops) ? 0 : -1; 1789 1790 synchronize_net(); 1791 1792 return ret; 1793 } 1794 EXPORT_SYMBOL(ip6_tnl_encap_del_ops); 1795 1796 int ip6_tnl_encap_setup(struct ip6_tnl *t, 1797 struct ip_tunnel_encap *ipencap) 1798 { 1799 int hlen; 1800 1801 memset(&t->encap, 0, sizeof(t->encap)); 1802 1803 hlen = ip6_encap_hlen(ipencap); 1804 if (hlen < 0) 1805 return hlen; 1806 1807 t->encap.type = ipencap->type; 1808 t->encap.sport = ipencap->sport; 1809 t->encap.dport = ipencap->dport; 1810 t->encap.flags = ipencap->flags; 1811 1812 t->encap_hlen = hlen; 1813 t->hlen = t->encap_hlen + t->tun_hlen; 1814 1815 return 0; 1816 } 1817 EXPORT_SYMBOL_GPL(ip6_tnl_encap_setup); 1818 1819 static const struct net_device_ops ip6_tnl_netdev_ops = { 1820 .ndo_init = ip6_tnl_dev_init, 1821 .ndo_uninit = ip6_tnl_dev_uninit, 1822 .ndo_start_xmit = ip6_tnl_start_xmit, 1823 .ndo_siocdevprivate = ip6_tnl_siocdevprivate, 1824 .ndo_change_mtu = ip6_tnl_change_mtu, 1825 .ndo_get_stats64 = dev_get_tstats64, 1826 .ndo_get_iflink = ip6_tnl_get_iflink, 1827 }; 1828 1829 #define IPXIPX_FEATURES (NETIF_F_SG | \ 1830 NETIF_F_FRAGLIST | \ 1831 NETIF_F_HIGHDMA | \ 1832 NETIF_F_GSO_SOFTWARE | \ 1833 NETIF_F_HW_CSUM) 1834 1835 /** 1836 * ip6_tnl_dev_setup - setup virtual tunnel device 1837 * @dev: virtual device associated with tunnel 1838 * 1839 * Description: 1840 * Initialize function pointers and device parameters 1841 **/ 1842 1843 static void ip6_tnl_dev_setup(struct net_device *dev) 1844 { 1845 dev->netdev_ops = &ip6_tnl_netdev_ops; 1846 dev->header_ops = &ip_tunnel_header_ops; 1847 dev->needs_free_netdev = true; 1848 dev->priv_destructor = ip6_dev_free; 1849 1850 dev->type = ARPHRD_TUNNEL6; 1851 dev->flags |= IFF_NOARP; 1852 dev->addr_len = sizeof(struct in6_addr); 1853 dev->features |= NETIF_F_LLTX; 1854 netif_keep_dst(dev); 1855 1856 dev->features |= IPXIPX_FEATURES; 1857 dev->hw_features |= IPXIPX_FEATURES; 1858 1859 /* This perm addr will be used as interface identifier by IPv6 */ 1860 dev->addr_assign_type = NET_ADDR_RANDOM; 1861 eth_random_addr(dev->perm_addr); 1862 } 1863 1864 1865 /** 1866 * ip6_tnl_dev_init_gen - general initializer for all tunnel devices 1867 * @dev: virtual device associated with tunnel 1868 **/ 1869 1870 static inline int 1871 ip6_tnl_dev_init_gen(struct net_device *dev) 1872 { 1873 struct ip6_tnl *t = netdev_priv(dev); 1874 int ret; 1875 int t_hlen; 1876 1877 t->dev = dev; 1878 t->net = dev_net(dev); 1879 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats); 1880 if (!dev->tstats) 1881 return -ENOMEM; 1882 1883 ret = dst_cache_init(&t->dst_cache, GFP_KERNEL); 1884 if (ret) 1885 goto free_stats; 1886 1887 ret = gro_cells_init(&t->gro_cells, dev); 1888 if (ret) 1889 goto destroy_dst; 1890 1891 t->tun_hlen = 0; 1892 t->hlen = t->encap_hlen + t->tun_hlen; 1893 t_hlen = t->hlen + sizeof(struct ipv6hdr); 1894 1895 dev->type = ARPHRD_TUNNEL6; 1896 dev->mtu = ETH_DATA_LEN - t_hlen; 1897 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1898 dev->mtu -= 8; 1899 dev->min_mtu = ETH_MIN_MTU; 1900 dev->max_mtu = IP6_MAX_MTU - dev->hard_header_len - t_hlen; 1901 1902 netdev_hold(dev, &t->dev_tracker, GFP_KERNEL); 1903 netdev_lockdep_set_classes(dev); 1904 return 0; 1905 1906 destroy_dst: 1907 dst_cache_destroy(&t->dst_cache); 1908 free_stats: 1909 free_percpu(dev->tstats); 1910 dev->tstats = NULL; 1911 1912 return ret; 1913 } 1914 1915 /** 1916 * ip6_tnl_dev_init - initializer for all non fallback tunnel devices 1917 * @dev: virtual device associated with tunnel 1918 **/ 1919 1920 static int ip6_tnl_dev_init(struct net_device *dev) 1921 { 1922 struct ip6_tnl *t = netdev_priv(dev); 1923 int err = ip6_tnl_dev_init_gen(dev); 1924 1925 if (err) 1926 return err; 1927 ip6_tnl_link_config(t); 1928 if (t->parms.collect_md) 1929 netif_keep_dst(dev); 1930 return 0; 1931 } 1932 1933 /** 1934 * ip6_fb_tnl_dev_init - initializer for fallback tunnel device 1935 * @dev: fallback device 1936 * 1937 * Return: 0 1938 **/ 1939 1940 static int __net_init ip6_fb_tnl_dev_init(struct net_device *dev) 1941 { 1942 struct ip6_tnl *t = netdev_priv(dev); 1943 struct net *net = dev_net(dev); 1944 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1945 1946 t->parms.proto = IPPROTO_IPV6; 1947 1948 rcu_assign_pointer(ip6n->tnls_wc[0], t); 1949 return 0; 1950 } 1951 1952 static int ip6_tnl_validate(struct nlattr *tb[], struct nlattr *data[], 1953 struct netlink_ext_ack *extack) 1954 { 1955 u8 proto; 1956 1957 if (!data || !data[IFLA_IPTUN_PROTO]) 1958 return 0; 1959 1960 proto = nla_get_u8(data[IFLA_IPTUN_PROTO]); 1961 if (proto != IPPROTO_IPV6 && 1962 proto != IPPROTO_IPIP && 1963 proto != 0) 1964 return -EINVAL; 1965 1966 return 0; 1967 } 1968 1969 static void ip6_tnl_netlink_parms(struct nlattr *data[], 1970 struct __ip6_tnl_parm *parms) 1971 { 1972 memset(parms, 0, sizeof(*parms)); 1973 1974 if (!data) 1975 return; 1976 1977 if (data[IFLA_IPTUN_LINK]) 1978 parms->link = nla_get_u32(data[IFLA_IPTUN_LINK]); 1979 1980 if (data[IFLA_IPTUN_LOCAL]) 1981 parms->laddr = nla_get_in6_addr(data[IFLA_IPTUN_LOCAL]); 1982 1983 if (data[IFLA_IPTUN_REMOTE]) 1984 parms->raddr = nla_get_in6_addr(data[IFLA_IPTUN_REMOTE]); 1985 1986 if (data[IFLA_IPTUN_TTL]) 1987 parms->hop_limit = nla_get_u8(data[IFLA_IPTUN_TTL]); 1988 1989 if (data[IFLA_IPTUN_ENCAP_LIMIT]) 1990 parms->encap_limit = nla_get_u8(data[IFLA_IPTUN_ENCAP_LIMIT]); 1991 1992 if (data[IFLA_IPTUN_FLOWINFO]) 1993 parms->flowinfo = nla_get_be32(data[IFLA_IPTUN_FLOWINFO]); 1994 1995 if (data[IFLA_IPTUN_FLAGS]) 1996 parms->flags = nla_get_u32(data[IFLA_IPTUN_FLAGS]); 1997 1998 if (data[IFLA_IPTUN_PROTO]) 1999 parms->proto = nla_get_u8(data[IFLA_IPTUN_PROTO]); 2000 2001 if (data[IFLA_IPTUN_COLLECT_METADATA]) 2002 parms->collect_md = true; 2003 2004 if (data[IFLA_IPTUN_FWMARK]) 2005 parms->fwmark = nla_get_u32(data[IFLA_IPTUN_FWMARK]); 2006 } 2007 2008 static int ip6_tnl_newlink(struct net *src_net, struct net_device *dev, 2009 struct nlattr *tb[], struct nlattr *data[], 2010 struct netlink_ext_ack *extack) 2011 { 2012 struct net *net = dev_net(dev); 2013 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 2014 struct ip_tunnel_encap ipencap; 2015 struct ip6_tnl *nt, *t; 2016 int err; 2017 2018 nt = netdev_priv(dev); 2019 2020 if (ip_tunnel_netlink_encap_parms(data, &ipencap)) { 2021 err = ip6_tnl_encap_setup(nt, &ipencap); 2022 if (err < 0) 2023 return err; 2024 } 2025 2026 ip6_tnl_netlink_parms(data, &nt->parms); 2027 2028 if (nt->parms.collect_md) { 2029 if (rtnl_dereference(ip6n->collect_md_tun)) 2030 return -EEXIST; 2031 } else { 2032 t = ip6_tnl_locate(net, &nt->parms, 0); 2033 if (!IS_ERR(t)) 2034 return -EEXIST; 2035 } 2036 2037 err = ip6_tnl_create2(dev); 2038 if (!err && tb[IFLA_MTU]) 2039 ip6_tnl_change_mtu(dev, nla_get_u32(tb[IFLA_MTU])); 2040 2041 return err; 2042 } 2043 2044 static int ip6_tnl_changelink(struct net_device *dev, struct nlattr *tb[], 2045 struct nlattr *data[], 2046 struct netlink_ext_ack *extack) 2047 { 2048 struct ip6_tnl *t = netdev_priv(dev); 2049 struct __ip6_tnl_parm p; 2050 struct net *net = t->net; 2051 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 2052 struct ip_tunnel_encap ipencap; 2053 2054 if (dev == ip6n->fb_tnl_dev) 2055 return -EINVAL; 2056 2057 if (ip_tunnel_netlink_encap_parms(data, &ipencap)) { 2058 int err = ip6_tnl_encap_setup(t, &ipencap); 2059 2060 if (err < 0) 2061 return err; 2062 } 2063 ip6_tnl_netlink_parms(data, &p); 2064 if (p.collect_md) 2065 return -EINVAL; 2066 2067 t = ip6_tnl_locate(net, &p, 0); 2068 if (!IS_ERR(t)) { 2069 if (t->dev != dev) 2070 return -EEXIST; 2071 } else 2072 t = netdev_priv(dev); 2073 2074 ip6_tnl_update(t, &p); 2075 return 0; 2076 } 2077 2078 static void ip6_tnl_dellink(struct net_device *dev, struct list_head *head) 2079 { 2080 struct net *net = dev_net(dev); 2081 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 2082 2083 if (dev != ip6n->fb_tnl_dev) 2084 unregister_netdevice_queue(dev, head); 2085 } 2086 2087 static size_t ip6_tnl_get_size(const struct net_device *dev) 2088 { 2089 return 2090 /* IFLA_IPTUN_LINK */ 2091 nla_total_size(4) + 2092 /* IFLA_IPTUN_LOCAL */ 2093 nla_total_size(sizeof(struct in6_addr)) + 2094 /* IFLA_IPTUN_REMOTE */ 2095 nla_total_size(sizeof(struct in6_addr)) + 2096 /* IFLA_IPTUN_TTL */ 2097 nla_total_size(1) + 2098 /* IFLA_IPTUN_ENCAP_LIMIT */ 2099 nla_total_size(1) + 2100 /* IFLA_IPTUN_FLOWINFO */ 2101 nla_total_size(4) + 2102 /* IFLA_IPTUN_FLAGS */ 2103 nla_total_size(4) + 2104 /* IFLA_IPTUN_PROTO */ 2105 nla_total_size(1) + 2106 /* IFLA_IPTUN_ENCAP_TYPE */ 2107 nla_total_size(2) + 2108 /* IFLA_IPTUN_ENCAP_FLAGS */ 2109 nla_total_size(2) + 2110 /* IFLA_IPTUN_ENCAP_SPORT */ 2111 nla_total_size(2) + 2112 /* IFLA_IPTUN_ENCAP_DPORT */ 2113 nla_total_size(2) + 2114 /* IFLA_IPTUN_COLLECT_METADATA */ 2115 nla_total_size(0) + 2116 /* IFLA_IPTUN_FWMARK */ 2117 nla_total_size(4) + 2118 0; 2119 } 2120 2121 static int ip6_tnl_fill_info(struct sk_buff *skb, const struct net_device *dev) 2122 { 2123 struct ip6_tnl *tunnel = netdev_priv(dev); 2124 struct __ip6_tnl_parm *parm = &tunnel->parms; 2125 2126 if (nla_put_u32(skb, IFLA_IPTUN_LINK, parm->link) || 2127 nla_put_in6_addr(skb, IFLA_IPTUN_LOCAL, &parm->laddr) || 2128 nla_put_in6_addr(skb, IFLA_IPTUN_REMOTE, &parm->raddr) || 2129 nla_put_u8(skb, IFLA_IPTUN_TTL, parm->hop_limit) || 2130 nla_put_u8(skb, IFLA_IPTUN_ENCAP_LIMIT, parm->encap_limit) || 2131 nla_put_be32(skb, IFLA_IPTUN_FLOWINFO, parm->flowinfo) || 2132 nla_put_u32(skb, IFLA_IPTUN_FLAGS, parm->flags) || 2133 nla_put_u8(skb, IFLA_IPTUN_PROTO, parm->proto) || 2134 nla_put_u32(skb, IFLA_IPTUN_FWMARK, parm->fwmark)) 2135 goto nla_put_failure; 2136 2137 if (nla_put_u16(skb, IFLA_IPTUN_ENCAP_TYPE, tunnel->encap.type) || 2138 nla_put_be16(skb, IFLA_IPTUN_ENCAP_SPORT, tunnel->encap.sport) || 2139 nla_put_be16(skb, IFLA_IPTUN_ENCAP_DPORT, tunnel->encap.dport) || 2140 nla_put_u16(skb, IFLA_IPTUN_ENCAP_FLAGS, tunnel->encap.flags)) 2141 goto nla_put_failure; 2142 2143 if (parm->collect_md) 2144 if (nla_put_flag(skb, IFLA_IPTUN_COLLECT_METADATA)) 2145 goto nla_put_failure; 2146 2147 return 0; 2148 2149 nla_put_failure: 2150 return -EMSGSIZE; 2151 } 2152 2153 struct net *ip6_tnl_get_link_net(const struct net_device *dev) 2154 { 2155 struct ip6_tnl *tunnel = netdev_priv(dev); 2156 2157 return tunnel->net; 2158 } 2159 EXPORT_SYMBOL(ip6_tnl_get_link_net); 2160 2161 static const struct nla_policy ip6_tnl_policy[IFLA_IPTUN_MAX + 1] = { 2162 [IFLA_IPTUN_LINK] = { .type = NLA_U32 }, 2163 [IFLA_IPTUN_LOCAL] = { .len = sizeof(struct in6_addr) }, 2164 [IFLA_IPTUN_REMOTE] = { .len = sizeof(struct in6_addr) }, 2165 [IFLA_IPTUN_TTL] = { .type = NLA_U8 }, 2166 [IFLA_IPTUN_ENCAP_LIMIT] = { .type = NLA_U8 }, 2167 [IFLA_IPTUN_FLOWINFO] = { .type = NLA_U32 }, 2168 [IFLA_IPTUN_FLAGS] = { .type = NLA_U32 }, 2169 [IFLA_IPTUN_PROTO] = { .type = NLA_U8 }, 2170 [IFLA_IPTUN_ENCAP_TYPE] = { .type = NLA_U16 }, 2171 [IFLA_IPTUN_ENCAP_FLAGS] = { .type = NLA_U16 }, 2172 [IFLA_IPTUN_ENCAP_SPORT] = { .type = NLA_U16 }, 2173 [IFLA_IPTUN_ENCAP_DPORT] = { .type = NLA_U16 }, 2174 [IFLA_IPTUN_COLLECT_METADATA] = { .type = NLA_FLAG }, 2175 [IFLA_IPTUN_FWMARK] = { .type = NLA_U32 }, 2176 }; 2177 2178 static struct rtnl_link_ops ip6_link_ops __read_mostly = { 2179 .kind = "ip6tnl", 2180 .maxtype = IFLA_IPTUN_MAX, 2181 .policy = ip6_tnl_policy, 2182 .priv_size = sizeof(struct ip6_tnl), 2183 .setup = ip6_tnl_dev_setup, 2184 .validate = ip6_tnl_validate, 2185 .newlink = ip6_tnl_newlink, 2186 .changelink = ip6_tnl_changelink, 2187 .dellink = ip6_tnl_dellink, 2188 .get_size = ip6_tnl_get_size, 2189 .fill_info = ip6_tnl_fill_info, 2190 .get_link_net = ip6_tnl_get_link_net, 2191 }; 2192 2193 static struct xfrm6_tunnel ip4ip6_handler __read_mostly = { 2194 .handler = ip4ip6_rcv, 2195 .err_handler = ip4ip6_err, 2196 .priority = 1, 2197 }; 2198 2199 static struct xfrm6_tunnel ip6ip6_handler __read_mostly = { 2200 .handler = ip6ip6_rcv, 2201 .err_handler = ip6ip6_err, 2202 .priority = 1, 2203 }; 2204 2205 static struct xfrm6_tunnel mplsip6_handler __read_mostly = { 2206 .handler = mplsip6_rcv, 2207 .err_handler = mplsip6_err, 2208 .priority = 1, 2209 }; 2210 2211 static void __net_exit ip6_tnl_destroy_tunnels(struct net *net, struct list_head *list) 2212 { 2213 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 2214 struct net_device *dev, *aux; 2215 int h; 2216 struct ip6_tnl *t; 2217 2218 for_each_netdev_safe(net, dev, aux) 2219 if (dev->rtnl_link_ops == &ip6_link_ops) 2220 unregister_netdevice_queue(dev, list); 2221 2222 for (h = 0; h < IP6_TUNNEL_HASH_SIZE; h++) { 2223 t = rtnl_dereference(ip6n->tnls_r_l[h]); 2224 while (t) { 2225 /* If dev is in the same netns, it has already 2226 * been added to the list by the previous loop. 2227 */ 2228 if (!net_eq(dev_net(t->dev), net)) 2229 unregister_netdevice_queue(t->dev, list); 2230 t = rtnl_dereference(t->next); 2231 } 2232 } 2233 2234 t = rtnl_dereference(ip6n->tnls_wc[0]); 2235 while (t) { 2236 /* If dev is in the same netns, it has already 2237 * been added to the list by the previous loop. 2238 */ 2239 if (!net_eq(dev_net(t->dev), net)) 2240 unregister_netdevice_queue(t->dev, list); 2241 t = rtnl_dereference(t->next); 2242 } 2243 } 2244 2245 static int __net_init ip6_tnl_init_net(struct net *net) 2246 { 2247 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 2248 struct ip6_tnl *t = NULL; 2249 int err; 2250 2251 ip6n->tnls[0] = ip6n->tnls_wc; 2252 ip6n->tnls[1] = ip6n->tnls_r_l; 2253 2254 if (!net_has_fallback_tunnels(net)) 2255 return 0; 2256 err = -ENOMEM; 2257 ip6n->fb_tnl_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6tnl0", 2258 NET_NAME_UNKNOWN, ip6_tnl_dev_setup); 2259 2260 if (!ip6n->fb_tnl_dev) 2261 goto err_alloc_dev; 2262 dev_net_set(ip6n->fb_tnl_dev, net); 2263 ip6n->fb_tnl_dev->rtnl_link_ops = &ip6_link_ops; 2264 /* FB netdevice is special: we have one, and only one per netns. 2265 * Allowing to move it to another netns is clearly unsafe. 2266 */ 2267 ip6n->fb_tnl_dev->features |= NETIF_F_NETNS_LOCAL; 2268 2269 err = ip6_fb_tnl_dev_init(ip6n->fb_tnl_dev); 2270 if (err < 0) 2271 goto err_register; 2272 2273 err = register_netdev(ip6n->fb_tnl_dev); 2274 if (err < 0) 2275 goto err_register; 2276 2277 t = netdev_priv(ip6n->fb_tnl_dev); 2278 2279 strcpy(t->parms.name, ip6n->fb_tnl_dev->name); 2280 return 0; 2281 2282 err_register: 2283 free_netdev(ip6n->fb_tnl_dev); 2284 err_alloc_dev: 2285 return err; 2286 } 2287 2288 static void __net_exit ip6_tnl_exit_batch_net(struct list_head *net_list) 2289 { 2290 struct net *net; 2291 LIST_HEAD(list); 2292 2293 rtnl_lock(); 2294 list_for_each_entry(net, net_list, exit_list) 2295 ip6_tnl_destroy_tunnels(net, &list); 2296 unregister_netdevice_many(&list); 2297 rtnl_unlock(); 2298 } 2299 2300 static struct pernet_operations ip6_tnl_net_ops = { 2301 .init = ip6_tnl_init_net, 2302 .exit_batch = ip6_tnl_exit_batch_net, 2303 .id = &ip6_tnl_net_id, 2304 .size = sizeof(struct ip6_tnl_net), 2305 }; 2306 2307 /** 2308 * ip6_tunnel_init - register protocol and reserve needed resources 2309 * 2310 * Return: 0 on success 2311 **/ 2312 2313 static int __init ip6_tunnel_init(void) 2314 { 2315 int err; 2316 2317 if (!ipv6_mod_enabled()) 2318 return -EOPNOTSUPP; 2319 2320 err = register_pernet_device(&ip6_tnl_net_ops); 2321 if (err < 0) 2322 goto out_pernet; 2323 2324 err = xfrm6_tunnel_register(&ip4ip6_handler, AF_INET); 2325 if (err < 0) { 2326 pr_err("%s: can't register ip4ip6\n", __func__); 2327 goto out_ip4ip6; 2328 } 2329 2330 err = xfrm6_tunnel_register(&ip6ip6_handler, AF_INET6); 2331 if (err < 0) { 2332 pr_err("%s: can't register ip6ip6\n", __func__); 2333 goto out_ip6ip6; 2334 } 2335 2336 if (ip6_tnl_mpls_supported()) { 2337 err = xfrm6_tunnel_register(&mplsip6_handler, AF_MPLS); 2338 if (err < 0) { 2339 pr_err("%s: can't register mplsip6\n", __func__); 2340 goto out_mplsip6; 2341 } 2342 } 2343 2344 err = rtnl_link_register(&ip6_link_ops); 2345 if (err < 0) 2346 goto rtnl_link_failed; 2347 2348 return 0; 2349 2350 rtnl_link_failed: 2351 if (ip6_tnl_mpls_supported()) 2352 xfrm6_tunnel_deregister(&mplsip6_handler, AF_MPLS); 2353 out_mplsip6: 2354 xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6); 2355 out_ip6ip6: 2356 xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET); 2357 out_ip4ip6: 2358 unregister_pernet_device(&ip6_tnl_net_ops); 2359 out_pernet: 2360 return err; 2361 } 2362 2363 /** 2364 * ip6_tunnel_cleanup - free resources and unregister protocol 2365 **/ 2366 2367 static void __exit ip6_tunnel_cleanup(void) 2368 { 2369 rtnl_link_unregister(&ip6_link_ops); 2370 if (xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET)) 2371 pr_info("%s: can't deregister ip4ip6\n", __func__); 2372 2373 if (xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6)) 2374 pr_info("%s: can't deregister ip6ip6\n", __func__); 2375 2376 if (ip6_tnl_mpls_supported() && 2377 xfrm6_tunnel_deregister(&mplsip6_handler, AF_MPLS)) 2378 pr_info("%s: can't deregister mplsip6\n", __func__); 2379 unregister_pernet_device(&ip6_tnl_net_ops); 2380 } 2381 2382 module_init(ip6_tunnel_init); 2383 module_exit(ip6_tunnel_cleanup); 2384