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 next, 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 struct frag_hdr *frag_hdr = (struct frag_hdr *) hdr; 414 if (frag_hdr->frag_off) 415 break; 416 optlen = 8; 417 } else if (nexthdr == NEXTHDR_AUTH) { 418 optlen = ipv6_authlen(hdr); 419 } else { 420 optlen = ipv6_optlen(hdr); 421 } 422 /* cache hdr->nexthdr, since pskb_may_pull() might 423 * invalidate hdr 424 */ 425 next = hdr->nexthdr; 426 if (nexthdr == NEXTHDR_DEST) { 427 u16 i = 2; 428 429 /* Remember : hdr is no longer valid at this point. */ 430 if (!pskb_may_pull(skb, off + optlen)) 431 break; 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 = next; 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 = ipv6_hdr(skb); 800 int 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 ipv6h = ipv6_hdr(skb); 833 skb->protocol = eth_type_trans(skb, tunnel->dev); 834 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN); 835 } else { 836 skb->dev = tunnel->dev; 837 skb_reset_mac_header(skb); 838 } 839 840 skb_reset_network_header(skb); 841 memset(skb->cb, 0, sizeof(struct inet6_skb_parm)); 842 843 __skb_tunnel_rx(skb, tunnel->dev, tunnel->net); 844 845 err = dscp_ecn_decapsulate(tunnel, ipv6h, skb); 846 if (unlikely(err)) { 847 if (log_ecn_err) 848 net_info_ratelimited("non-ECT from %pI6 with DS=%#x\n", 849 &ipv6h->saddr, 850 ipv6_get_dsfield(ipv6h)); 851 if (err > 1) { 852 DEV_STATS_INC(tunnel->dev, rx_frame_errors); 853 DEV_STATS_INC(tunnel->dev, rx_errors); 854 goto drop; 855 } 856 } 857 858 dev_sw_netstats_rx_add(tunnel->dev, skb->len); 859 860 skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(tunnel->dev))); 861 862 if (tun_dst) 863 skb_dst_set(skb, (struct dst_entry *)tun_dst); 864 865 gro_cells_receive(&tunnel->gro_cells, skb); 866 return 0; 867 868 drop: 869 if (tun_dst) 870 dst_release((struct dst_entry *)tun_dst); 871 kfree_skb(skb); 872 return 0; 873 } 874 875 int ip6_tnl_rcv(struct ip6_tnl *t, struct sk_buff *skb, 876 const struct tnl_ptk_info *tpi, 877 struct metadata_dst *tun_dst, 878 bool log_ecn_err) 879 { 880 int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t, 881 const struct ipv6hdr *ipv6h, 882 struct sk_buff *skb); 883 884 dscp_ecn_decapsulate = ip6ip6_dscp_ecn_decapsulate; 885 if (tpi->proto == htons(ETH_P_IP)) 886 dscp_ecn_decapsulate = ip4ip6_dscp_ecn_decapsulate; 887 888 return __ip6_tnl_rcv(t, skb, tpi, tun_dst, dscp_ecn_decapsulate, 889 log_ecn_err); 890 } 891 EXPORT_SYMBOL(ip6_tnl_rcv); 892 893 static const struct tnl_ptk_info tpi_v6 = { 894 /* no tunnel info required for ipxip6. */ 895 .proto = htons(ETH_P_IPV6), 896 }; 897 898 static const struct tnl_ptk_info tpi_v4 = { 899 /* no tunnel info required for ipxip6. */ 900 .proto = htons(ETH_P_IP), 901 }; 902 903 static const struct tnl_ptk_info tpi_mpls = { 904 /* no tunnel info required for mplsip6. */ 905 .proto = htons(ETH_P_MPLS_UC), 906 }; 907 908 static int ipxip6_rcv(struct sk_buff *skb, u8 ipproto, 909 const struct tnl_ptk_info *tpi, 910 int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t, 911 const struct ipv6hdr *ipv6h, 912 struct sk_buff *skb)) 913 { 914 struct ip6_tnl *t; 915 const struct ipv6hdr *ipv6h = ipv6_hdr(skb); 916 struct metadata_dst *tun_dst = NULL; 917 int ret = -1; 918 919 rcu_read_lock(); 920 t = ip6_tnl_lookup(dev_net(skb->dev), skb->dev->ifindex, &ipv6h->saddr, &ipv6h->daddr); 921 922 if (t) { 923 u8 tproto = READ_ONCE(t->parms.proto); 924 925 if (tproto != ipproto && tproto != 0) 926 goto drop; 927 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) 928 goto drop; 929 ipv6h = ipv6_hdr(skb); 930 if (!ip6_tnl_rcv_ctl(t, &ipv6h->daddr, &ipv6h->saddr)) 931 goto drop; 932 if (iptunnel_pull_header(skb, 0, tpi->proto, false)) 933 goto drop; 934 if (t->parms.collect_md) { 935 tun_dst = ipv6_tun_rx_dst(skb, 0, 0, 0); 936 if (!tun_dst) 937 goto drop; 938 } 939 ret = __ip6_tnl_rcv(t, skb, tpi, tun_dst, dscp_ecn_decapsulate, 940 log_ecn_error); 941 } 942 943 rcu_read_unlock(); 944 945 return ret; 946 947 drop: 948 rcu_read_unlock(); 949 kfree_skb(skb); 950 return 0; 951 } 952 953 static int ip4ip6_rcv(struct sk_buff *skb) 954 { 955 return ipxip6_rcv(skb, IPPROTO_IPIP, &tpi_v4, 956 ip4ip6_dscp_ecn_decapsulate); 957 } 958 959 static int ip6ip6_rcv(struct sk_buff *skb) 960 { 961 return ipxip6_rcv(skb, IPPROTO_IPV6, &tpi_v6, 962 ip6ip6_dscp_ecn_decapsulate); 963 } 964 965 static int mplsip6_rcv(struct sk_buff *skb) 966 { 967 return ipxip6_rcv(skb, IPPROTO_MPLS, &tpi_mpls, 968 mplsip6_dscp_ecn_decapsulate); 969 } 970 971 struct ipv6_tel_txoption { 972 struct ipv6_txoptions ops; 973 __u8 dst_opt[8]; 974 }; 975 976 static void init_tel_txopt(struct ipv6_tel_txoption *opt, __u8 encap_limit) 977 { 978 memset(opt, 0, sizeof(struct ipv6_tel_txoption)); 979 980 opt->dst_opt[2] = IPV6_TLV_TNL_ENCAP_LIMIT; 981 opt->dst_opt[3] = 1; 982 opt->dst_opt[4] = encap_limit; 983 opt->dst_opt[5] = IPV6_TLV_PADN; 984 opt->dst_opt[6] = 1; 985 986 opt->ops.dst1opt = (struct ipv6_opt_hdr *) opt->dst_opt; 987 opt->ops.opt_nflen = 8; 988 } 989 990 /** 991 * ip6_tnl_addr_conflict - compare packet addresses to tunnel's own 992 * @t: the outgoing tunnel device 993 * @hdr: IPv6 header from the incoming packet 994 * 995 * Description: 996 * Avoid trivial tunneling loop by checking that tunnel exit-point 997 * doesn't match source of incoming packet. 998 * 999 * Return: 1000 * 1 if conflict, 1001 * 0 else 1002 **/ 1003 1004 static inline bool 1005 ip6_tnl_addr_conflict(const struct ip6_tnl *t, const struct ipv6hdr *hdr) 1006 { 1007 return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr); 1008 } 1009 1010 int ip6_tnl_xmit_ctl(struct ip6_tnl *t, 1011 const struct in6_addr *laddr, 1012 const struct in6_addr *raddr) 1013 { 1014 struct __ip6_tnl_parm *p = &t->parms; 1015 int ret = 0; 1016 struct net *net = t->net; 1017 1018 if (t->parms.collect_md) 1019 return 1; 1020 1021 if ((p->flags & IP6_TNL_F_CAP_XMIT) || 1022 ((p->flags & IP6_TNL_F_CAP_PER_PACKET) && 1023 (ip6_tnl_get_cap(t, laddr, raddr) & IP6_TNL_F_CAP_XMIT))) { 1024 struct net_device *ldev = NULL; 1025 1026 rcu_read_lock(); 1027 if (p->link) 1028 ldev = dev_get_by_index_rcu(net, p->link); 1029 1030 if (unlikely(!ipv6_chk_addr_and_flags(net, laddr, ldev, false, 1031 0, IFA_F_TENTATIVE))) 1032 pr_warn_ratelimited("%s xmit: Local address not yet configured!\n", 1033 p->name); 1034 else if (!(p->flags & IP6_TNL_F_ALLOW_LOCAL_REMOTE) && 1035 !ipv6_addr_is_multicast(raddr) && 1036 unlikely(ipv6_chk_addr_and_flags(net, raddr, ldev, 1037 true, 0, IFA_F_TENTATIVE))) 1038 pr_warn_ratelimited("%s xmit: Routing loop! Remote address found on this node!\n", 1039 p->name); 1040 else 1041 ret = 1; 1042 rcu_read_unlock(); 1043 } 1044 return ret; 1045 } 1046 EXPORT_SYMBOL_GPL(ip6_tnl_xmit_ctl); 1047 1048 /** 1049 * ip6_tnl_xmit - encapsulate packet and send 1050 * @skb: the outgoing socket buffer 1051 * @dev: the outgoing tunnel device 1052 * @dsfield: dscp code for outer header 1053 * @fl6: flow of tunneled packet 1054 * @encap_limit: encapsulation limit 1055 * @pmtu: Path MTU is stored if packet is too big 1056 * @proto: next header value 1057 * 1058 * Description: 1059 * Build new header and do some sanity checks on the packet before sending 1060 * it. 1061 * 1062 * Return: 1063 * 0 on success 1064 * -1 fail 1065 * %-EMSGSIZE message too big. return mtu in this case. 1066 **/ 1067 1068 int ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev, __u8 dsfield, 1069 struct flowi6 *fl6, int encap_limit, __u32 *pmtu, 1070 __u8 proto) 1071 { 1072 struct ip6_tnl *t = netdev_priv(dev); 1073 struct net *net = t->net; 1074 struct ipv6hdr *ipv6h; 1075 struct ipv6_tel_txoption opt; 1076 struct dst_entry *dst = NULL, *ndst = NULL; 1077 struct net_device *tdev; 1078 int mtu; 1079 unsigned int eth_hlen = t->dev->type == ARPHRD_ETHER ? ETH_HLEN : 0; 1080 unsigned int psh_hlen = sizeof(struct ipv6hdr) + t->encap_hlen; 1081 unsigned int max_headroom = psh_hlen; 1082 __be16 payload_protocol; 1083 bool use_cache = false; 1084 u8 hop_limit; 1085 int err = -1; 1086 1087 payload_protocol = skb_protocol(skb, true); 1088 1089 if (t->parms.collect_md) { 1090 hop_limit = skb_tunnel_info(skb)->key.ttl; 1091 goto route_lookup; 1092 } else { 1093 hop_limit = t->parms.hop_limit; 1094 } 1095 1096 /* NBMA tunnel */ 1097 if (ipv6_addr_any(&t->parms.raddr)) { 1098 if (payload_protocol == htons(ETH_P_IPV6)) { 1099 struct in6_addr *addr6; 1100 struct neighbour *neigh; 1101 int addr_type; 1102 1103 if (!skb_dst(skb)) 1104 goto tx_err_link_failure; 1105 1106 neigh = dst_neigh_lookup(skb_dst(skb), 1107 &ipv6_hdr(skb)->daddr); 1108 if (!neigh) 1109 goto tx_err_link_failure; 1110 1111 addr6 = (struct in6_addr *)&neigh->primary_key; 1112 addr_type = ipv6_addr_type(addr6); 1113 1114 if (addr_type == IPV6_ADDR_ANY) 1115 addr6 = &ipv6_hdr(skb)->daddr; 1116 1117 memcpy(&fl6->daddr, addr6, sizeof(fl6->daddr)); 1118 neigh_release(neigh); 1119 } else if (payload_protocol == htons(ETH_P_IP)) { 1120 const struct rtable *rt = skb_rtable(skb); 1121 1122 if (!rt) 1123 goto tx_err_link_failure; 1124 1125 if (rt->rt_gw_family == AF_INET6) 1126 memcpy(&fl6->daddr, &rt->rt_gw6, sizeof(fl6->daddr)); 1127 } 1128 } else if (t->parms.proto != 0 && !(t->parms.flags & 1129 (IP6_TNL_F_USE_ORIG_TCLASS | 1130 IP6_TNL_F_USE_ORIG_FWMARK))) { 1131 /* enable the cache only if neither the outer protocol nor the 1132 * routing decision depends on the current inner header value 1133 */ 1134 use_cache = true; 1135 } 1136 1137 if (use_cache) 1138 dst = dst_cache_get(&t->dst_cache); 1139 1140 if (!ip6_tnl_xmit_ctl(t, &fl6->saddr, &fl6->daddr)) 1141 goto tx_err_link_failure; 1142 1143 if (!dst) { 1144 route_lookup: 1145 /* add dsfield to flowlabel for route lookup */ 1146 fl6->flowlabel = ip6_make_flowinfo(dsfield, fl6->flowlabel); 1147 1148 dst = ip6_route_output(net, NULL, fl6); 1149 1150 if (dst->error) 1151 goto tx_err_link_failure; 1152 dst = xfrm_lookup(net, dst, flowi6_to_flowi(fl6), NULL, 0); 1153 if (IS_ERR(dst)) { 1154 err = PTR_ERR(dst); 1155 dst = NULL; 1156 goto tx_err_link_failure; 1157 } 1158 if (t->parms.collect_md && ipv6_addr_any(&fl6->saddr) && 1159 ipv6_dev_get_saddr(net, ip6_dst_idev(dst)->dev, 1160 &fl6->daddr, 0, &fl6->saddr)) 1161 goto tx_err_link_failure; 1162 ndst = dst; 1163 } 1164 1165 tdev = dst->dev; 1166 1167 if (tdev == dev) { 1168 DEV_STATS_INC(dev, collisions); 1169 net_warn_ratelimited("%s: Local routing loop detected!\n", 1170 t->parms.name); 1171 goto tx_err_dst_release; 1172 } 1173 mtu = dst_mtu(dst) - eth_hlen - psh_hlen - t->tun_hlen; 1174 if (encap_limit >= 0) { 1175 max_headroom += 8; 1176 mtu -= 8; 1177 } 1178 mtu = max(mtu, skb->protocol == htons(ETH_P_IPV6) ? 1179 IPV6_MIN_MTU : IPV4_MIN_MTU); 1180 1181 skb_dst_update_pmtu_no_confirm(skb, mtu); 1182 if (skb->len - t->tun_hlen - eth_hlen > mtu && !skb_is_gso(skb)) { 1183 *pmtu = mtu; 1184 err = -EMSGSIZE; 1185 goto tx_err_dst_release; 1186 } 1187 1188 if (t->err_count > 0) { 1189 if (time_before(jiffies, 1190 t->err_time + IP6TUNNEL_ERR_TIMEO)) { 1191 t->err_count--; 1192 1193 dst_link_failure(skb); 1194 } else { 1195 t->err_count = 0; 1196 } 1197 } 1198 1199 skb_scrub_packet(skb, !net_eq(t->net, dev_net(dev))); 1200 1201 /* 1202 * Okay, now see if we can stuff it in the buffer as-is. 1203 */ 1204 max_headroom += LL_RESERVED_SPACE(tdev); 1205 1206 if (skb_headroom(skb) < max_headroom || skb_shared(skb) || 1207 (skb_cloned(skb) && !skb_clone_writable(skb, 0))) { 1208 struct sk_buff *new_skb; 1209 1210 new_skb = skb_realloc_headroom(skb, max_headroom); 1211 if (!new_skb) 1212 goto tx_err_dst_release; 1213 1214 if (skb->sk) 1215 skb_set_owner_w(new_skb, skb->sk); 1216 consume_skb(skb); 1217 skb = new_skb; 1218 } 1219 1220 if (t->parms.collect_md) { 1221 if (t->encap.type != TUNNEL_ENCAP_NONE) 1222 goto tx_err_dst_release; 1223 } else { 1224 if (use_cache && ndst) 1225 dst_cache_set_ip6(&t->dst_cache, ndst, &fl6->saddr); 1226 } 1227 skb_dst_set(skb, dst); 1228 1229 if (hop_limit == 0) { 1230 if (payload_protocol == htons(ETH_P_IP)) 1231 hop_limit = ip_hdr(skb)->ttl; 1232 else if (payload_protocol == htons(ETH_P_IPV6)) 1233 hop_limit = ipv6_hdr(skb)->hop_limit; 1234 else 1235 hop_limit = ip6_dst_hoplimit(dst); 1236 } 1237 1238 /* Calculate max headroom for all the headers and adjust 1239 * needed_headroom if necessary. 1240 */ 1241 max_headroom = LL_RESERVED_SPACE(dst->dev) + sizeof(struct ipv6hdr) 1242 + dst->header_len + t->hlen; 1243 if (max_headroom > READ_ONCE(dev->needed_headroom)) 1244 WRITE_ONCE(dev->needed_headroom, max_headroom); 1245 1246 err = ip6_tnl_encap(skb, t, &proto, fl6); 1247 if (err) 1248 return err; 1249 1250 if (encap_limit >= 0) { 1251 init_tel_txopt(&opt, encap_limit); 1252 ipv6_push_frag_opts(skb, &opt.ops, &proto); 1253 } 1254 1255 skb_push(skb, sizeof(struct ipv6hdr)); 1256 skb_reset_network_header(skb); 1257 ipv6h = ipv6_hdr(skb); 1258 ip6_flow_hdr(ipv6h, dsfield, 1259 ip6_make_flowlabel(net, skb, fl6->flowlabel, true, fl6)); 1260 ipv6h->hop_limit = hop_limit; 1261 ipv6h->nexthdr = proto; 1262 ipv6h->saddr = fl6->saddr; 1263 ipv6h->daddr = fl6->daddr; 1264 ip6tunnel_xmit(NULL, skb, dev); 1265 return 0; 1266 tx_err_link_failure: 1267 DEV_STATS_INC(dev, tx_carrier_errors); 1268 dst_link_failure(skb); 1269 tx_err_dst_release: 1270 dst_release(dst); 1271 return err; 1272 } 1273 EXPORT_SYMBOL(ip6_tnl_xmit); 1274 1275 static inline int 1276 ipxip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev, 1277 u8 protocol) 1278 { 1279 struct ip6_tnl *t = netdev_priv(dev); 1280 struct ipv6hdr *ipv6h; 1281 const struct iphdr *iph; 1282 int encap_limit = -1; 1283 __u16 offset; 1284 struct flowi6 fl6; 1285 __u8 dsfield, orig_dsfield; 1286 __u32 mtu; 1287 u8 tproto; 1288 int err; 1289 1290 tproto = READ_ONCE(t->parms.proto); 1291 if (tproto != protocol && tproto != 0) 1292 return -1; 1293 1294 if (t->parms.collect_md) { 1295 struct ip_tunnel_info *tun_info; 1296 const struct ip_tunnel_key *key; 1297 1298 tun_info = skb_tunnel_info(skb); 1299 if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) || 1300 ip_tunnel_info_af(tun_info) != AF_INET6)) 1301 return -1; 1302 key = &tun_info->key; 1303 memset(&fl6, 0, sizeof(fl6)); 1304 fl6.flowi6_proto = protocol; 1305 fl6.saddr = key->u.ipv6.src; 1306 fl6.daddr = key->u.ipv6.dst; 1307 fl6.flowlabel = key->label; 1308 dsfield = key->tos; 1309 switch (protocol) { 1310 case IPPROTO_IPIP: 1311 iph = ip_hdr(skb); 1312 orig_dsfield = ipv4_get_dsfield(iph); 1313 break; 1314 case IPPROTO_IPV6: 1315 ipv6h = ipv6_hdr(skb); 1316 orig_dsfield = ipv6_get_dsfield(ipv6h); 1317 break; 1318 default: 1319 orig_dsfield = dsfield; 1320 break; 1321 } 1322 } else { 1323 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1324 encap_limit = t->parms.encap_limit; 1325 if (protocol == IPPROTO_IPV6) { 1326 offset = ip6_tnl_parse_tlv_enc_lim(skb, 1327 skb_network_header(skb)); 1328 /* ip6_tnl_parse_tlv_enc_lim() might have 1329 * reallocated skb->head 1330 */ 1331 if (offset > 0) { 1332 struct ipv6_tlv_tnl_enc_lim *tel; 1333 1334 tel = (void *)&skb_network_header(skb)[offset]; 1335 if (tel->encap_limit == 0) { 1336 icmpv6_ndo_send(skb, ICMPV6_PARAMPROB, 1337 ICMPV6_HDR_FIELD, offset + 2); 1338 return -1; 1339 } 1340 encap_limit = tel->encap_limit - 1; 1341 } 1342 } 1343 1344 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 1345 fl6.flowi6_proto = protocol; 1346 1347 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK) 1348 fl6.flowi6_mark = skb->mark; 1349 else 1350 fl6.flowi6_mark = t->parms.fwmark; 1351 switch (protocol) { 1352 case IPPROTO_IPIP: 1353 iph = ip_hdr(skb); 1354 orig_dsfield = ipv4_get_dsfield(iph); 1355 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) 1356 dsfield = orig_dsfield; 1357 else 1358 dsfield = ip6_tclass(t->parms.flowinfo); 1359 break; 1360 case IPPROTO_IPV6: 1361 ipv6h = ipv6_hdr(skb); 1362 orig_dsfield = ipv6_get_dsfield(ipv6h); 1363 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) 1364 dsfield = orig_dsfield; 1365 else 1366 dsfield = ip6_tclass(t->parms.flowinfo); 1367 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL) 1368 fl6.flowlabel |= ip6_flowlabel(ipv6h); 1369 break; 1370 default: 1371 orig_dsfield = dsfield = ip6_tclass(t->parms.flowinfo); 1372 break; 1373 } 1374 } 1375 1376 fl6.flowi6_uid = sock_net_uid(dev_net(dev), NULL); 1377 dsfield = INET_ECN_encapsulate(dsfield, orig_dsfield); 1378 1379 if (iptunnel_handle_offloads(skb, SKB_GSO_IPXIP6)) 1380 return -1; 1381 1382 skb_set_inner_ipproto(skb, protocol); 1383 1384 err = ip6_tnl_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu, 1385 protocol); 1386 if (err != 0) { 1387 /* XXX: send ICMP error even if DF is not set. */ 1388 if (err == -EMSGSIZE) 1389 switch (protocol) { 1390 case IPPROTO_IPIP: 1391 icmp_ndo_send(skb, ICMP_DEST_UNREACH, 1392 ICMP_FRAG_NEEDED, htonl(mtu)); 1393 break; 1394 case IPPROTO_IPV6: 1395 icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); 1396 break; 1397 default: 1398 break; 1399 } 1400 return -1; 1401 } 1402 1403 return 0; 1404 } 1405 1406 static netdev_tx_t 1407 ip6_tnl_start_xmit(struct sk_buff *skb, struct net_device *dev) 1408 { 1409 struct ip6_tnl *t = netdev_priv(dev); 1410 u8 ipproto; 1411 int ret; 1412 1413 if (!pskb_inet_may_pull(skb)) 1414 goto tx_err; 1415 1416 switch (skb->protocol) { 1417 case htons(ETH_P_IP): 1418 ipproto = IPPROTO_IPIP; 1419 break; 1420 case htons(ETH_P_IPV6): 1421 if (ip6_tnl_addr_conflict(t, ipv6_hdr(skb))) 1422 goto tx_err; 1423 ipproto = IPPROTO_IPV6; 1424 break; 1425 case htons(ETH_P_MPLS_UC): 1426 ipproto = IPPROTO_MPLS; 1427 break; 1428 default: 1429 goto tx_err; 1430 } 1431 1432 ret = ipxip6_tnl_xmit(skb, dev, ipproto); 1433 if (ret < 0) 1434 goto tx_err; 1435 1436 return NETDEV_TX_OK; 1437 1438 tx_err: 1439 DEV_STATS_INC(dev, tx_errors); 1440 DEV_STATS_INC(dev, tx_dropped); 1441 kfree_skb(skb); 1442 return NETDEV_TX_OK; 1443 } 1444 1445 static void ip6_tnl_link_config(struct ip6_tnl *t) 1446 { 1447 struct net_device *dev = t->dev; 1448 struct net_device *tdev = NULL; 1449 struct __ip6_tnl_parm *p = &t->parms; 1450 struct flowi6 *fl6 = &t->fl.u.ip6; 1451 int t_hlen; 1452 int mtu; 1453 1454 __dev_addr_set(dev, &p->laddr, sizeof(struct in6_addr)); 1455 memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr)); 1456 1457 /* Set up flowi template */ 1458 fl6->saddr = p->laddr; 1459 fl6->daddr = p->raddr; 1460 fl6->flowi6_oif = p->link; 1461 fl6->flowlabel = 0; 1462 1463 if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS)) 1464 fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo; 1465 if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL)) 1466 fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo; 1467 1468 p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET); 1469 p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr); 1470 1471 if (p->flags&IP6_TNL_F_CAP_XMIT && p->flags&IP6_TNL_F_CAP_RCV) 1472 dev->flags |= IFF_POINTOPOINT; 1473 else 1474 dev->flags &= ~IFF_POINTOPOINT; 1475 1476 t->tun_hlen = 0; 1477 t->hlen = t->encap_hlen + t->tun_hlen; 1478 t_hlen = t->hlen + sizeof(struct ipv6hdr); 1479 1480 if (p->flags & IP6_TNL_F_CAP_XMIT) { 1481 int strict = (ipv6_addr_type(&p->raddr) & 1482 (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL)); 1483 1484 struct rt6_info *rt = rt6_lookup(t->net, 1485 &p->raddr, &p->laddr, 1486 p->link, NULL, strict); 1487 if (rt) { 1488 tdev = rt->dst.dev; 1489 ip6_rt_put(rt); 1490 } 1491 1492 if (!tdev && p->link) 1493 tdev = __dev_get_by_index(t->net, p->link); 1494 1495 if (tdev) { 1496 dev->hard_header_len = tdev->hard_header_len + t_hlen; 1497 mtu = min_t(unsigned int, tdev->mtu, IP6_MAX_MTU); 1498 1499 mtu = mtu - t_hlen; 1500 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1501 mtu -= 8; 1502 1503 if (mtu < IPV6_MIN_MTU) 1504 mtu = IPV6_MIN_MTU; 1505 WRITE_ONCE(dev->mtu, mtu); 1506 } 1507 } 1508 } 1509 1510 /** 1511 * ip6_tnl_change - update the tunnel parameters 1512 * @t: tunnel to be changed 1513 * @p: tunnel configuration parameters 1514 * 1515 * Description: 1516 * ip6_tnl_change() updates the tunnel parameters 1517 **/ 1518 1519 static void 1520 ip6_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p) 1521 { 1522 t->parms.laddr = p->laddr; 1523 t->parms.raddr = p->raddr; 1524 t->parms.flags = p->flags; 1525 t->parms.hop_limit = p->hop_limit; 1526 t->parms.encap_limit = p->encap_limit; 1527 t->parms.flowinfo = p->flowinfo; 1528 t->parms.link = p->link; 1529 t->parms.proto = p->proto; 1530 t->parms.fwmark = p->fwmark; 1531 dst_cache_reset(&t->dst_cache); 1532 ip6_tnl_link_config(t); 1533 } 1534 1535 static void ip6_tnl_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p) 1536 { 1537 struct net *net = t->net; 1538 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1539 1540 ip6_tnl_unlink(ip6n, t); 1541 synchronize_net(); 1542 ip6_tnl_change(t, p); 1543 ip6_tnl_link(ip6n, t); 1544 netdev_state_change(t->dev); 1545 } 1546 1547 static void ip6_tnl0_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p) 1548 { 1549 /* for default tnl0 device allow to change only the proto */ 1550 t->parms.proto = p->proto; 1551 netdev_state_change(t->dev); 1552 } 1553 1554 static void 1555 ip6_tnl_parm_from_user(struct __ip6_tnl_parm *p, const struct ip6_tnl_parm *u) 1556 { 1557 p->laddr = u->laddr; 1558 p->raddr = u->raddr; 1559 p->flags = u->flags; 1560 p->hop_limit = u->hop_limit; 1561 p->encap_limit = u->encap_limit; 1562 p->flowinfo = u->flowinfo; 1563 p->link = u->link; 1564 p->proto = u->proto; 1565 memcpy(p->name, u->name, sizeof(u->name)); 1566 } 1567 1568 static void 1569 ip6_tnl_parm_to_user(struct ip6_tnl_parm *u, const struct __ip6_tnl_parm *p) 1570 { 1571 u->laddr = p->laddr; 1572 u->raddr = p->raddr; 1573 u->flags = p->flags; 1574 u->hop_limit = p->hop_limit; 1575 u->encap_limit = p->encap_limit; 1576 u->flowinfo = p->flowinfo; 1577 u->link = p->link; 1578 u->proto = p->proto; 1579 memcpy(u->name, p->name, sizeof(u->name)); 1580 } 1581 1582 /** 1583 * ip6_tnl_siocdevprivate - configure ipv6 tunnels from userspace 1584 * @dev: virtual device associated with tunnel 1585 * @ifr: unused 1586 * @data: parameters passed from userspace 1587 * @cmd: command to be performed 1588 * 1589 * Description: 1590 * ip6_tnl_ioctl() is used for managing IPv6 tunnels 1591 * from userspace. 1592 * 1593 * The possible commands are the following: 1594 * %SIOCGETTUNNEL: get tunnel parameters for device 1595 * %SIOCADDTUNNEL: add tunnel matching given tunnel parameters 1596 * %SIOCCHGTUNNEL: change tunnel parameters to those given 1597 * %SIOCDELTUNNEL: delete tunnel 1598 * 1599 * The fallback device "ip6tnl0", created during module 1600 * initialization, can be used for creating other tunnel devices. 1601 * 1602 * Return: 1603 * 0 on success, 1604 * %-EFAULT if unable to copy data to or from userspace, 1605 * %-EPERM if current process hasn't %CAP_NET_ADMIN set 1606 * %-EINVAL if passed tunnel parameters are invalid, 1607 * %-EEXIST if changing a tunnel's parameters would cause a conflict 1608 * %-ENODEV if attempting to change or delete a nonexisting device 1609 **/ 1610 1611 static int 1612 ip6_tnl_siocdevprivate(struct net_device *dev, struct ifreq *ifr, 1613 void __user *data, int cmd) 1614 { 1615 int err = 0; 1616 struct ip6_tnl_parm p; 1617 struct __ip6_tnl_parm p1; 1618 struct ip6_tnl *t = netdev_priv(dev); 1619 struct net *net = t->net; 1620 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1621 1622 memset(&p1, 0, sizeof(p1)); 1623 1624 switch (cmd) { 1625 case SIOCGETTUNNEL: 1626 if (dev == ip6n->fb_tnl_dev) { 1627 if (copy_from_user(&p, data, sizeof(p))) { 1628 err = -EFAULT; 1629 break; 1630 } 1631 ip6_tnl_parm_from_user(&p1, &p); 1632 t = ip6_tnl_locate(net, &p1, 0); 1633 if (IS_ERR(t)) 1634 t = netdev_priv(dev); 1635 } else { 1636 memset(&p, 0, sizeof(p)); 1637 } 1638 ip6_tnl_parm_to_user(&p, &t->parms); 1639 if (copy_to_user(data, &p, sizeof(p))) 1640 err = -EFAULT; 1641 break; 1642 case SIOCADDTUNNEL: 1643 case SIOCCHGTUNNEL: 1644 err = -EPERM; 1645 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 1646 break; 1647 err = -EFAULT; 1648 if (copy_from_user(&p, data, sizeof(p))) 1649 break; 1650 err = -EINVAL; 1651 if (p.proto != IPPROTO_IPV6 && p.proto != IPPROTO_IPIP && 1652 p.proto != 0) 1653 break; 1654 ip6_tnl_parm_from_user(&p1, &p); 1655 t = ip6_tnl_locate(net, &p1, cmd == SIOCADDTUNNEL); 1656 if (cmd == SIOCCHGTUNNEL) { 1657 if (!IS_ERR(t)) { 1658 if (t->dev != dev) { 1659 err = -EEXIST; 1660 break; 1661 } 1662 } else 1663 t = netdev_priv(dev); 1664 if (dev == ip6n->fb_tnl_dev) 1665 ip6_tnl0_update(t, &p1); 1666 else 1667 ip6_tnl_update(t, &p1); 1668 } 1669 if (!IS_ERR(t)) { 1670 err = 0; 1671 ip6_tnl_parm_to_user(&p, &t->parms); 1672 if (copy_to_user(data, &p, sizeof(p))) 1673 err = -EFAULT; 1674 1675 } else { 1676 err = PTR_ERR(t); 1677 } 1678 break; 1679 case SIOCDELTUNNEL: 1680 err = -EPERM; 1681 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 1682 break; 1683 1684 if (dev == ip6n->fb_tnl_dev) { 1685 err = -EFAULT; 1686 if (copy_from_user(&p, data, sizeof(p))) 1687 break; 1688 err = -ENOENT; 1689 ip6_tnl_parm_from_user(&p1, &p); 1690 t = ip6_tnl_locate(net, &p1, 0); 1691 if (IS_ERR(t)) 1692 break; 1693 err = -EPERM; 1694 if (t->dev == ip6n->fb_tnl_dev) 1695 break; 1696 dev = t->dev; 1697 } 1698 err = 0; 1699 unregister_netdevice(dev); 1700 break; 1701 default: 1702 err = -EINVAL; 1703 } 1704 return err; 1705 } 1706 1707 /** 1708 * ip6_tnl_change_mtu - change mtu manually for tunnel device 1709 * @dev: virtual device associated with tunnel 1710 * @new_mtu: the new mtu 1711 * 1712 * Return: 1713 * 0 on success, 1714 * %-EINVAL if mtu too small 1715 **/ 1716 1717 int ip6_tnl_change_mtu(struct net_device *dev, int new_mtu) 1718 { 1719 struct ip6_tnl *tnl = netdev_priv(dev); 1720 1721 if (tnl->parms.proto == IPPROTO_IPV6) { 1722 if (new_mtu < IPV6_MIN_MTU) 1723 return -EINVAL; 1724 } else { 1725 if (new_mtu < ETH_MIN_MTU) 1726 return -EINVAL; 1727 } 1728 if (tnl->parms.proto == IPPROTO_IPV6 || tnl->parms.proto == 0) { 1729 if (new_mtu > IP6_MAX_MTU - dev->hard_header_len) 1730 return -EINVAL; 1731 } else { 1732 if (new_mtu > IP_MAX_MTU - dev->hard_header_len) 1733 return -EINVAL; 1734 } 1735 dev->mtu = new_mtu; 1736 return 0; 1737 } 1738 EXPORT_SYMBOL(ip6_tnl_change_mtu); 1739 1740 int ip6_tnl_get_iflink(const struct net_device *dev) 1741 { 1742 struct ip6_tnl *t = netdev_priv(dev); 1743 1744 return t->parms.link; 1745 } 1746 EXPORT_SYMBOL(ip6_tnl_get_iflink); 1747 1748 int ip6_tnl_encap_add_ops(const struct ip6_tnl_encap_ops *ops, 1749 unsigned int num) 1750 { 1751 if (num >= MAX_IPTUN_ENCAP_OPS) 1752 return -ERANGE; 1753 1754 return !cmpxchg((const struct ip6_tnl_encap_ops **) 1755 &ip6tun_encaps[num], 1756 NULL, ops) ? 0 : -1; 1757 } 1758 EXPORT_SYMBOL(ip6_tnl_encap_add_ops); 1759 1760 int ip6_tnl_encap_del_ops(const struct ip6_tnl_encap_ops *ops, 1761 unsigned int num) 1762 { 1763 int ret; 1764 1765 if (num >= MAX_IPTUN_ENCAP_OPS) 1766 return -ERANGE; 1767 1768 ret = (cmpxchg((const struct ip6_tnl_encap_ops **) 1769 &ip6tun_encaps[num], 1770 ops, NULL) == ops) ? 0 : -1; 1771 1772 synchronize_net(); 1773 1774 return ret; 1775 } 1776 EXPORT_SYMBOL(ip6_tnl_encap_del_ops); 1777 1778 int ip6_tnl_encap_setup(struct ip6_tnl *t, 1779 struct ip_tunnel_encap *ipencap) 1780 { 1781 int hlen; 1782 1783 memset(&t->encap, 0, sizeof(t->encap)); 1784 1785 hlen = ip6_encap_hlen(ipencap); 1786 if (hlen < 0) 1787 return hlen; 1788 1789 t->encap.type = ipencap->type; 1790 t->encap.sport = ipencap->sport; 1791 t->encap.dport = ipencap->dport; 1792 t->encap.flags = ipencap->flags; 1793 1794 t->encap_hlen = hlen; 1795 t->hlen = t->encap_hlen + t->tun_hlen; 1796 1797 return 0; 1798 } 1799 EXPORT_SYMBOL_GPL(ip6_tnl_encap_setup); 1800 1801 static const struct net_device_ops ip6_tnl_netdev_ops = { 1802 .ndo_init = ip6_tnl_dev_init, 1803 .ndo_uninit = ip6_tnl_dev_uninit, 1804 .ndo_start_xmit = ip6_tnl_start_xmit, 1805 .ndo_siocdevprivate = ip6_tnl_siocdevprivate, 1806 .ndo_change_mtu = ip6_tnl_change_mtu, 1807 .ndo_get_stats64 = dev_get_tstats64, 1808 .ndo_get_iflink = ip6_tnl_get_iflink, 1809 }; 1810 1811 #define IPXIPX_FEATURES (NETIF_F_SG | \ 1812 NETIF_F_FRAGLIST | \ 1813 NETIF_F_HIGHDMA | \ 1814 NETIF_F_GSO_SOFTWARE | \ 1815 NETIF_F_HW_CSUM) 1816 1817 /** 1818 * ip6_tnl_dev_setup - setup virtual tunnel device 1819 * @dev: virtual device associated with tunnel 1820 * 1821 * Description: 1822 * Initialize function pointers and device parameters 1823 **/ 1824 1825 static void ip6_tnl_dev_setup(struct net_device *dev) 1826 { 1827 dev->netdev_ops = &ip6_tnl_netdev_ops; 1828 dev->header_ops = &ip_tunnel_header_ops; 1829 dev->needs_free_netdev = true; 1830 dev->priv_destructor = ip6_dev_free; 1831 1832 dev->type = ARPHRD_TUNNEL6; 1833 dev->flags |= IFF_NOARP; 1834 dev->addr_len = sizeof(struct in6_addr); 1835 dev->features |= NETIF_F_LLTX; 1836 netif_keep_dst(dev); 1837 1838 dev->features |= IPXIPX_FEATURES; 1839 dev->hw_features |= IPXIPX_FEATURES; 1840 1841 /* This perm addr will be used as interface identifier by IPv6 */ 1842 dev->addr_assign_type = NET_ADDR_RANDOM; 1843 eth_random_addr(dev->perm_addr); 1844 } 1845 1846 1847 /** 1848 * ip6_tnl_dev_init_gen - general initializer for all tunnel devices 1849 * @dev: virtual device associated with tunnel 1850 **/ 1851 1852 static inline int 1853 ip6_tnl_dev_init_gen(struct net_device *dev) 1854 { 1855 struct ip6_tnl *t = netdev_priv(dev); 1856 int ret; 1857 int t_hlen; 1858 1859 t->dev = dev; 1860 t->net = dev_net(dev); 1861 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats); 1862 if (!dev->tstats) 1863 return -ENOMEM; 1864 1865 ret = dst_cache_init(&t->dst_cache, GFP_KERNEL); 1866 if (ret) 1867 goto free_stats; 1868 1869 ret = gro_cells_init(&t->gro_cells, dev); 1870 if (ret) 1871 goto destroy_dst; 1872 1873 t->tun_hlen = 0; 1874 t->hlen = t->encap_hlen + t->tun_hlen; 1875 t_hlen = t->hlen + sizeof(struct ipv6hdr); 1876 1877 dev->type = ARPHRD_TUNNEL6; 1878 dev->hard_header_len = LL_MAX_HEADER + t_hlen; 1879 dev->mtu = ETH_DATA_LEN - t_hlen; 1880 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1881 dev->mtu -= 8; 1882 dev->min_mtu = ETH_MIN_MTU; 1883 dev->max_mtu = IP6_MAX_MTU - dev->hard_header_len; 1884 1885 netdev_hold(dev, &t->dev_tracker, GFP_KERNEL); 1886 return 0; 1887 1888 destroy_dst: 1889 dst_cache_destroy(&t->dst_cache); 1890 free_stats: 1891 free_percpu(dev->tstats); 1892 dev->tstats = NULL; 1893 1894 return ret; 1895 } 1896 1897 /** 1898 * ip6_tnl_dev_init - initializer for all non fallback tunnel devices 1899 * @dev: virtual device associated with tunnel 1900 **/ 1901 1902 static int ip6_tnl_dev_init(struct net_device *dev) 1903 { 1904 struct ip6_tnl *t = netdev_priv(dev); 1905 int err = ip6_tnl_dev_init_gen(dev); 1906 1907 if (err) 1908 return err; 1909 ip6_tnl_link_config(t); 1910 if (t->parms.collect_md) 1911 netif_keep_dst(dev); 1912 return 0; 1913 } 1914 1915 /** 1916 * ip6_fb_tnl_dev_init - initializer for fallback tunnel device 1917 * @dev: fallback device 1918 * 1919 * Return: 0 1920 **/ 1921 1922 static int __net_init ip6_fb_tnl_dev_init(struct net_device *dev) 1923 { 1924 struct ip6_tnl *t = netdev_priv(dev); 1925 struct net *net = dev_net(dev); 1926 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1927 1928 t->parms.proto = IPPROTO_IPV6; 1929 1930 rcu_assign_pointer(ip6n->tnls_wc[0], t); 1931 return 0; 1932 } 1933 1934 static int ip6_tnl_validate(struct nlattr *tb[], struct nlattr *data[], 1935 struct netlink_ext_ack *extack) 1936 { 1937 u8 proto; 1938 1939 if (!data || !data[IFLA_IPTUN_PROTO]) 1940 return 0; 1941 1942 proto = nla_get_u8(data[IFLA_IPTUN_PROTO]); 1943 if (proto != IPPROTO_IPV6 && 1944 proto != IPPROTO_IPIP && 1945 proto != 0) 1946 return -EINVAL; 1947 1948 return 0; 1949 } 1950 1951 static void ip6_tnl_netlink_parms(struct nlattr *data[], 1952 struct __ip6_tnl_parm *parms) 1953 { 1954 memset(parms, 0, sizeof(*parms)); 1955 1956 if (!data) 1957 return; 1958 1959 if (data[IFLA_IPTUN_LINK]) 1960 parms->link = nla_get_u32(data[IFLA_IPTUN_LINK]); 1961 1962 if (data[IFLA_IPTUN_LOCAL]) 1963 parms->laddr = nla_get_in6_addr(data[IFLA_IPTUN_LOCAL]); 1964 1965 if (data[IFLA_IPTUN_REMOTE]) 1966 parms->raddr = nla_get_in6_addr(data[IFLA_IPTUN_REMOTE]); 1967 1968 if (data[IFLA_IPTUN_TTL]) 1969 parms->hop_limit = nla_get_u8(data[IFLA_IPTUN_TTL]); 1970 1971 if (data[IFLA_IPTUN_ENCAP_LIMIT]) 1972 parms->encap_limit = nla_get_u8(data[IFLA_IPTUN_ENCAP_LIMIT]); 1973 1974 if (data[IFLA_IPTUN_FLOWINFO]) 1975 parms->flowinfo = nla_get_be32(data[IFLA_IPTUN_FLOWINFO]); 1976 1977 if (data[IFLA_IPTUN_FLAGS]) 1978 parms->flags = nla_get_u32(data[IFLA_IPTUN_FLAGS]); 1979 1980 if (data[IFLA_IPTUN_PROTO]) 1981 parms->proto = nla_get_u8(data[IFLA_IPTUN_PROTO]); 1982 1983 if (data[IFLA_IPTUN_COLLECT_METADATA]) 1984 parms->collect_md = true; 1985 1986 if (data[IFLA_IPTUN_FWMARK]) 1987 parms->fwmark = nla_get_u32(data[IFLA_IPTUN_FWMARK]); 1988 } 1989 1990 static int ip6_tnl_newlink(struct net *src_net, struct net_device *dev, 1991 struct nlattr *tb[], struct nlattr *data[], 1992 struct netlink_ext_ack *extack) 1993 { 1994 struct net *net = dev_net(dev); 1995 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1996 struct ip_tunnel_encap ipencap; 1997 struct ip6_tnl *nt, *t; 1998 int err; 1999 2000 nt = netdev_priv(dev); 2001 2002 if (ip_tunnel_netlink_encap_parms(data, &ipencap)) { 2003 err = ip6_tnl_encap_setup(nt, &ipencap); 2004 if (err < 0) 2005 return err; 2006 } 2007 2008 ip6_tnl_netlink_parms(data, &nt->parms); 2009 2010 if (nt->parms.collect_md) { 2011 if (rtnl_dereference(ip6n->collect_md_tun)) 2012 return -EEXIST; 2013 } else { 2014 t = ip6_tnl_locate(net, &nt->parms, 0); 2015 if (!IS_ERR(t)) 2016 return -EEXIST; 2017 } 2018 2019 err = ip6_tnl_create2(dev); 2020 if (!err && tb[IFLA_MTU]) 2021 ip6_tnl_change_mtu(dev, nla_get_u32(tb[IFLA_MTU])); 2022 2023 return err; 2024 } 2025 2026 static int ip6_tnl_changelink(struct net_device *dev, struct nlattr *tb[], 2027 struct nlattr *data[], 2028 struct netlink_ext_ack *extack) 2029 { 2030 struct ip6_tnl *t = netdev_priv(dev); 2031 struct __ip6_tnl_parm p; 2032 struct net *net = t->net; 2033 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 2034 struct ip_tunnel_encap ipencap; 2035 2036 if (dev == ip6n->fb_tnl_dev) 2037 return -EINVAL; 2038 2039 if (ip_tunnel_netlink_encap_parms(data, &ipencap)) { 2040 int err = ip6_tnl_encap_setup(t, &ipencap); 2041 2042 if (err < 0) 2043 return err; 2044 } 2045 ip6_tnl_netlink_parms(data, &p); 2046 if (p.collect_md) 2047 return -EINVAL; 2048 2049 t = ip6_tnl_locate(net, &p, 0); 2050 if (!IS_ERR(t)) { 2051 if (t->dev != dev) 2052 return -EEXIST; 2053 } else 2054 t = netdev_priv(dev); 2055 2056 ip6_tnl_update(t, &p); 2057 return 0; 2058 } 2059 2060 static void ip6_tnl_dellink(struct net_device *dev, struct list_head *head) 2061 { 2062 struct net *net = dev_net(dev); 2063 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 2064 2065 if (dev != ip6n->fb_tnl_dev) 2066 unregister_netdevice_queue(dev, head); 2067 } 2068 2069 static size_t ip6_tnl_get_size(const struct net_device *dev) 2070 { 2071 return 2072 /* IFLA_IPTUN_LINK */ 2073 nla_total_size(4) + 2074 /* IFLA_IPTUN_LOCAL */ 2075 nla_total_size(sizeof(struct in6_addr)) + 2076 /* IFLA_IPTUN_REMOTE */ 2077 nla_total_size(sizeof(struct in6_addr)) + 2078 /* IFLA_IPTUN_TTL */ 2079 nla_total_size(1) + 2080 /* IFLA_IPTUN_ENCAP_LIMIT */ 2081 nla_total_size(1) + 2082 /* IFLA_IPTUN_FLOWINFO */ 2083 nla_total_size(4) + 2084 /* IFLA_IPTUN_FLAGS */ 2085 nla_total_size(4) + 2086 /* IFLA_IPTUN_PROTO */ 2087 nla_total_size(1) + 2088 /* IFLA_IPTUN_ENCAP_TYPE */ 2089 nla_total_size(2) + 2090 /* IFLA_IPTUN_ENCAP_FLAGS */ 2091 nla_total_size(2) + 2092 /* IFLA_IPTUN_ENCAP_SPORT */ 2093 nla_total_size(2) + 2094 /* IFLA_IPTUN_ENCAP_DPORT */ 2095 nla_total_size(2) + 2096 /* IFLA_IPTUN_COLLECT_METADATA */ 2097 nla_total_size(0) + 2098 /* IFLA_IPTUN_FWMARK */ 2099 nla_total_size(4) + 2100 0; 2101 } 2102 2103 static int ip6_tnl_fill_info(struct sk_buff *skb, const struct net_device *dev) 2104 { 2105 struct ip6_tnl *tunnel = netdev_priv(dev); 2106 struct __ip6_tnl_parm *parm = &tunnel->parms; 2107 2108 if (nla_put_u32(skb, IFLA_IPTUN_LINK, parm->link) || 2109 nla_put_in6_addr(skb, IFLA_IPTUN_LOCAL, &parm->laddr) || 2110 nla_put_in6_addr(skb, IFLA_IPTUN_REMOTE, &parm->raddr) || 2111 nla_put_u8(skb, IFLA_IPTUN_TTL, parm->hop_limit) || 2112 nla_put_u8(skb, IFLA_IPTUN_ENCAP_LIMIT, parm->encap_limit) || 2113 nla_put_be32(skb, IFLA_IPTUN_FLOWINFO, parm->flowinfo) || 2114 nla_put_u32(skb, IFLA_IPTUN_FLAGS, parm->flags) || 2115 nla_put_u8(skb, IFLA_IPTUN_PROTO, parm->proto) || 2116 nla_put_u32(skb, IFLA_IPTUN_FWMARK, parm->fwmark)) 2117 goto nla_put_failure; 2118 2119 if (nla_put_u16(skb, IFLA_IPTUN_ENCAP_TYPE, tunnel->encap.type) || 2120 nla_put_be16(skb, IFLA_IPTUN_ENCAP_SPORT, tunnel->encap.sport) || 2121 nla_put_be16(skb, IFLA_IPTUN_ENCAP_DPORT, tunnel->encap.dport) || 2122 nla_put_u16(skb, IFLA_IPTUN_ENCAP_FLAGS, tunnel->encap.flags)) 2123 goto nla_put_failure; 2124 2125 if (parm->collect_md) 2126 if (nla_put_flag(skb, IFLA_IPTUN_COLLECT_METADATA)) 2127 goto nla_put_failure; 2128 2129 return 0; 2130 2131 nla_put_failure: 2132 return -EMSGSIZE; 2133 } 2134 2135 struct net *ip6_tnl_get_link_net(const struct net_device *dev) 2136 { 2137 struct ip6_tnl *tunnel = netdev_priv(dev); 2138 2139 return tunnel->net; 2140 } 2141 EXPORT_SYMBOL(ip6_tnl_get_link_net); 2142 2143 static const struct nla_policy ip6_tnl_policy[IFLA_IPTUN_MAX + 1] = { 2144 [IFLA_IPTUN_LINK] = { .type = NLA_U32 }, 2145 [IFLA_IPTUN_LOCAL] = { .len = sizeof(struct in6_addr) }, 2146 [IFLA_IPTUN_REMOTE] = { .len = sizeof(struct in6_addr) }, 2147 [IFLA_IPTUN_TTL] = { .type = NLA_U8 }, 2148 [IFLA_IPTUN_ENCAP_LIMIT] = { .type = NLA_U8 }, 2149 [IFLA_IPTUN_FLOWINFO] = { .type = NLA_U32 }, 2150 [IFLA_IPTUN_FLAGS] = { .type = NLA_U32 }, 2151 [IFLA_IPTUN_PROTO] = { .type = NLA_U8 }, 2152 [IFLA_IPTUN_ENCAP_TYPE] = { .type = NLA_U16 }, 2153 [IFLA_IPTUN_ENCAP_FLAGS] = { .type = NLA_U16 }, 2154 [IFLA_IPTUN_ENCAP_SPORT] = { .type = NLA_U16 }, 2155 [IFLA_IPTUN_ENCAP_DPORT] = { .type = NLA_U16 }, 2156 [IFLA_IPTUN_COLLECT_METADATA] = { .type = NLA_FLAG }, 2157 [IFLA_IPTUN_FWMARK] = { .type = NLA_U32 }, 2158 }; 2159 2160 static struct rtnl_link_ops ip6_link_ops __read_mostly = { 2161 .kind = "ip6tnl", 2162 .maxtype = IFLA_IPTUN_MAX, 2163 .policy = ip6_tnl_policy, 2164 .priv_size = sizeof(struct ip6_tnl), 2165 .setup = ip6_tnl_dev_setup, 2166 .validate = ip6_tnl_validate, 2167 .newlink = ip6_tnl_newlink, 2168 .changelink = ip6_tnl_changelink, 2169 .dellink = ip6_tnl_dellink, 2170 .get_size = ip6_tnl_get_size, 2171 .fill_info = ip6_tnl_fill_info, 2172 .get_link_net = ip6_tnl_get_link_net, 2173 }; 2174 2175 static struct xfrm6_tunnel ip4ip6_handler __read_mostly = { 2176 .handler = ip4ip6_rcv, 2177 .err_handler = ip4ip6_err, 2178 .priority = 1, 2179 }; 2180 2181 static struct xfrm6_tunnel ip6ip6_handler __read_mostly = { 2182 .handler = ip6ip6_rcv, 2183 .err_handler = ip6ip6_err, 2184 .priority = 1, 2185 }; 2186 2187 static struct xfrm6_tunnel mplsip6_handler __read_mostly = { 2188 .handler = mplsip6_rcv, 2189 .err_handler = mplsip6_err, 2190 .priority = 1, 2191 }; 2192 2193 static void __net_exit ip6_tnl_destroy_tunnels(struct net *net, struct list_head *list) 2194 { 2195 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 2196 struct net_device *dev, *aux; 2197 int h; 2198 struct ip6_tnl *t; 2199 2200 for_each_netdev_safe(net, dev, aux) 2201 if (dev->rtnl_link_ops == &ip6_link_ops) 2202 unregister_netdevice_queue(dev, list); 2203 2204 for (h = 0; h < IP6_TUNNEL_HASH_SIZE; h++) { 2205 t = rtnl_dereference(ip6n->tnls_r_l[h]); 2206 while (t) { 2207 /* If dev is in the same netns, it has already 2208 * been added to the list by the previous loop. 2209 */ 2210 if (!net_eq(dev_net(t->dev), net)) 2211 unregister_netdevice_queue(t->dev, list); 2212 t = rtnl_dereference(t->next); 2213 } 2214 } 2215 2216 t = rtnl_dereference(ip6n->tnls_wc[0]); 2217 while (t) { 2218 /* If dev is in the same netns, it has already 2219 * been added to the list by the previous loop. 2220 */ 2221 if (!net_eq(dev_net(t->dev), net)) 2222 unregister_netdevice_queue(t->dev, list); 2223 t = rtnl_dereference(t->next); 2224 } 2225 } 2226 2227 static int __net_init ip6_tnl_init_net(struct net *net) 2228 { 2229 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 2230 struct ip6_tnl *t = NULL; 2231 int err; 2232 2233 ip6n->tnls[0] = ip6n->tnls_wc; 2234 ip6n->tnls[1] = ip6n->tnls_r_l; 2235 2236 if (!net_has_fallback_tunnels(net)) 2237 return 0; 2238 err = -ENOMEM; 2239 ip6n->fb_tnl_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6tnl0", 2240 NET_NAME_UNKNOWN, ip6_tnl_dev_setup); 2241 2242 if (!ip6n->fb_tnl_dev) 2243 goto err_alloc_dev; 2244 dev_net_set(ip6n->fb_tnl_dev, net); 2245 ip6n->fb_tnl_dev->rtnl_link_ops = &ip6_link_ops; 2246 /* FB netdevice is special: we have one, and only one per netns. 2247 * Allowing to move it to another netns is clearly unsafe. 2248 */ 2249 ip6n->fb_tnl_dev->features |= NETIF_F_NETNS_LOCAL; 2250 2251 err = ip6_fb_tnl_dev_init(ip6n->fb_tnl_dev); 2252 if (err < 0) 2253 goto err_register; 2254 2255 err = register_netdev(ip6n->fb_tnl_dev); 2256 if (err < 0) 2257 goto err_register; 2258 2259 t = netdev_priv(ip6n->fb_tnl_dev); 2260 2261 strcpy(t->parms.name, ip6n->fb_tnl_dev->name); 2262 return 0; 2263 2264 err_register: 2265 free_netdev(ip6n->fb_tnl_dev); 2266 err_alloc_dev: 2267 return err; 2268 } 2269 2270 static void __net_exit ip6_tnl_exit_batch_net(struct list_head *net_list) 2271 { 2272 struct net *net; 2273 LIST_HEAD(list); 2274 2275 rtnl_lock(); 2276 list_for_each_entry(net, net_list, exit_list) 2277 ip6_tnl_destroy_tunnels(net, &list); 2278 unregister_netdevice_many(&list); 2279 rtnl_unlock(); 2280 } 2281 2282 static struct pernet_operations ip6_tnl_net_ops = { 2283 .init = ip6_tnl_init_net, 2284 .exit_batch = ip6_tnl_exit_batch_net, 2285 .id = &ip6_tnl_net_id, 2286 .size = sizeof(struct ip6_tnl_net), 2287 }; 2288 2289 /** 2290 * ip6_tunnel_init - register protocol and reserve needed resources 2291 * 2292 * Return: 0 on success 2293 **/ 2294 2295 static int __init ip6_tunnel_init(void) 2296 { 2297 int err; 2298 2299 if (!ipv6_mod_enabled()) 2300 return -EOPNOTSUPP; 2301 2302 err = register_pernet_device(&ip6_tnl_net_ops); 2303 if (err < 0) 2304 goto out_pernet; 2305 2306 err = xfrm6_tunnel_register(&ip4ip6_handler, AF_INET); 2307 if (err < 0) { 2308 pr_err("%s: can't register ip4ip6\n", __func__); 2309 goto out_ip4ip6; 2310 } 2311 2312 err = xfrm6_tunnel_register(&ip6ip6_handler, AF_INET6); 2313 if (err < 0) { 2314 pr_err("%s: can't register ip6ip6\n", __func__); 2315 goto out_ip6ip6; 2316 } 2317 2318 if (ip6_tnl_mpls_supported()) { 2319 err = xfrm6_tunnel_register(&mplsip6_handler, AF_MPLS); 2320 if (err < 0) { 2321 pr_err("%s: can't register mplsip6\n", __func__); 2322 goto out_mplsip6; 2323 } 2324 } 2325 2326 err = rtnl_link_register(&ip6_link_ops); 2327 if (err < 0) 2328 goto rtnl_link_failed; 2329 2330 return 0; 2331 2332 rtnl_link_failed: 2333 if (ip6_tnl_mpls_supported()) 2334 xfrm6_tunnel_deregister(&mplsip6_handler, AF_MPLS); 2335 out_mplsip6: 2336 xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6); 2337 out_ip6ip6: 2338 xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET); 2339 out_ip4ip6: 2340 unregister_pernet_device(&ip6_tnl_net_ops); 2341 out_pernet: 2342 return err; 2343 } 2344 2345 /** 2346 * ip6_tunnel_cleanup - free resources and unregister protocol 2347 **/ 2348 2349 static void __exit ip6_tunnel_cleanup(void) 2350 { 2351 rtnl_link_unregister(&ip6_link_ops); 2352 if (xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET)) 2353 pr_info("%s: can't deregister ip4ip6\n", __func__); 2354 2355 if (xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6)) 2356 pr_info("%s: can't deregister ip6ip6\n", __func__); 2357 2358 if (ip6_tnl_mpls_supported() && 2359 xfrm6_tunnel_deregister(&mplsip6_handler, AF_MPLS)) 2360 pr_info("%s: can't deregister mplsip6\n", __func__); 2361 unregister_pernet_device(&ip6_tnl_net_ops); 2362 } 2363 2364 module_init(ip6_tunnel_init); 2365 module_exit(ip6_tunnel_cleanup); 2366