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 strlcpy(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 dev_put_track(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 struct pcpu_sw_netstats *tstats; 800 const struct ipv6hdr *ipv6h = ipv6_hdr(skb); 801 int err; 802 803 if ((!(tpi->flags & TUNNEL_CSUM) && 804 (tunnel->parms.i_flags & TUNNEL_CSUM)) || 805 ((tpi->flags & TUNNEL_CSUM) && 806 !(tunnel->parms.i_flags & TUNNEL_CSUM))) { 807 tunnel->dev->stats.rx_crc_errors++; 808 tunnel->dev->stats.rx_errors++; 809 goto drop; 810 } 811 812 if (tunnel->parms.i_flags & TUNNEL_SEQ) { 813 if (!(tpi->flags & TUNNEL_SEQ) || 814 (tunnel->i_seqno && 815 (s32)(ntohl(tpi->seq) - tunnel->i_seqno) < 0)) { 816 tunnel->dev->stats.rx_fifo_errors++; 817 tunnel->dev->stats.rx_errors++; 818 goto drop; 819 } 820 tunnel->i_seqno = ntohl(tpi->seq) + 1; 821 } 822 823 skb->protocol = tpi->proto; 824 825 /* Warning: All skb pointers will be invalidated! */ 826 if (tunnel->dev->type == ARPHRD_ETHER) { 827 if (!pskb_may_pull(skb, ETH_HLEN)) { 828 tunnel->dev->stats.rx_length_errors++; 829 tunnel->dev->stats.rx_errors++; 830 goto drop; 831 } 832 833 ipv6h = ipv6_hdr(skb); 834 skb->protocol = eth_type_trans(skb, tunnel->dev); 835 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN); 836 } else { 837 skb->dev = tunnel->dev; 838 skb_reset_mac_header(skb); 839 } 840 841 skb_reset_network_header(skb); 842 memset(skb->cb, 0, sizeof(struct inet6_skb_parm)); 843 844 __skb_tunnel_rx(skb, tunnel->dev, tunnel->net); 845 846 err = dscp_ecn_decapsulate(tunnel, ipv6h, skb); 847 if (unlikely(err)) { 848 if (log_ecn_err) 849 net_info_ratelimited("non-ECT from %pI6 with DS=%#x\n", 850 &ipv6h->saddr, 851 ipv6_get_dsfield(ipv6h)); 852 if (err > 1) { 853 ++tunnel->dev->stats.rx_frame_errors; 854 ++tunnel->dev->stats.rx_errors; 855 goto drop; 856 } 857 } 858 859 tstats = this_cpu_ptr(tunnel->dev->tstats); 860 u64_stats_update_begin(&tstats->syncp); 861 tstats->rx_packets++; 862 tstats->rx_bytes += skb->len; 863 u64_stats_update_end(&tstats->syncp); 864 865 skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(tunnel->dev))); 866 867 if (tun_dst) 868 skb_dst_set(skb, (struct dst_entry *)tun_dst); 869 870 gro_cells_receive(&tunnel->gro_cells, skb); 871 return 0; 872 873 drop: 874 if (tun_dst) 875 dst_release((struct dst_entry *)tun_dst); 876 kfree_skb(skb); 877 return 0; 878 } 879 880 int ip6_tnl_rcv(struct ip6_tnl *t, struct sk_buff *skb, 881 const struct tnl_ptk_info *tpi, 882 struct metadata_dst *tun_dst, 883 bool log_ecn_err) 884 { 885 int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t, 886 const struct ipv6hdr *ipv6h, 887 struct sk_buff *skb); 888 889 dscp_ecn_decapsulate = ip6ip6_dscp_ecn_decapsulate; 890 if (tpi->proto == htons(ETH_P_IP)) 891 dscp_ecn_decapsulate = ip4ip6_dscp_ecn_decapsulate; 892 893 return __ip6_tnl_rcv(t, skb, tpi, tun_dst, dscp_ecn_decapsulate, 894 log_ecn_err); 895 } 896 EXPORT_SYMBOL(ip6_tnl_rcv); 897 898 static const struct tnl_ptk_info tpi_v6 = { 899 /* no tunnel info required for ipxip6. */ 900 .proto = htons(ETH_P_IPV6), 901 }; 902 903 static const struct tnl_ptk_info tpi_v4 = { 904 /* no tunnel info required for ipxip6. */ 905 .proto = htons(ETH_P_IP), 906 }; 907 908 static const struct tnl_ptk_info tpi_mpls = { 909 /* no tunnel info required for mplsip6. */ 910 .proto = htons(ETH_P_MPLS_UC), 911 }; 912 913 static int ipxip6_rcv(struct sk_buff *skb, u8 ipproto, 914 const struct tnl_ptk_info *tpi, 915 int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t, 916 const struct ipv6hdr *ipv6h, 917 struct sk_buff *skb)) 918 { 919 struct ip6_tnl *t; 920 const struct ipv6hdr *ipv6h = ipv6_hdr(skb); 921 struct metadata_dst *tun_dst = NULL; 922 int ret = -1; 923 924 rcu_read_lock(); 925 t = ip6_tnl_lookup(dev_net(skb->dev), skb->dev->ifindex, &ipv6h->saddr, &ipv6h->daddr); 926 927 if (t) { 928 u8 tproto = READ_ONCE(t->parms.proto); 929 930 if (tproto != ipproto && tproto != 0) 931 goto drop; 932 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) 933 goto drop; 934 ipv6h = ipv6_hdr(skb); 935 if (!ip6_tnl_rcv_ctl(t, &ipv6h->daddr, &ipv6h->saddr)) 936 goto drop; 937 if (iptunnel_pull_header(skb, 0, tpi->proto, false)) 938 goto drop; 939 if (t->parms.collect_md) { 940 tun_dst = ipv6_tun_rx_dst(skb, 0, 0, 0); 941 if (!tun_dst) 942 goto drop; 943 } 944 ret = __ip6_tnl_rcv(t, skb, tpi, tun_dst, dscp_ecn_decapsulate, 945 log_ecn_error); 946 } 947 948 rcu_read_unlock(); 949 950 return ret; 951 952 drop: 953 rcu_read_unlock(); 954 kfree_skb(skb); 955 return 0; 956 } 957 958 static int ip4ip6_rcv(struct sk_buff *skb) 959 { 960 return ipxip6_rcv(skb, IPPROTO_IPIP, &tpi_v4, 961 ip4ip6_dscp_ecn_decapsulate); 962 } 963 964 static int ip6ip6_rcv(struct sk_buff *skb) 965 { 966 return ipxip6_rcv(skb, IPPROTO_IPV6, &tpi_v6, 967 ip6ip6_dscp_ecn_decapsulate); 968 } 969 970 static int mplsip6_rcv(struct sk_buff *skb) 971 { 972 return ipxip6_rcv(skb, IPPROTO_MPLS, &tpi_mpls, 973 mplsip6_dscp_ecn_decapsulate); 974 } 975 976 struct ipv6_tel_txoption { 977 struct ipv6_txoptions ops; 978 __u8 dst_opt[8]; 979 }; 980 981 static void init_tel_txopt(struct ipv6_tel_txoption *opt, __u8 encap_limit) 982 { 983 memset(opt, 0, sizeof(struct ipv6_tel_txoption)); 984 985 opt->dst_opt[2] = IPV6_TLV_TNL_ENCAP_LIMIT; 986 opt->dst_opt[3] = 1; 987 opt->dst_opt[4] = encap_limit; 988 opt->dst_opt[5] = IPV6_TLV_PADN; 989 opt->dst_opt[6] = 1; 990 991 opt->ops.dst1opt = (struct ipv6_opt_hdr *) opt->dst_opt; 992 opt->ops.opt_nflen = 8; 993 } 994 995 /** 996 * ip6_tnl_addr_conflict - compare packet addresses to tunnel's own 997 * @t: the outgoing tunnel device 998 * @hdr: IPv6 header from the incoming packet 999 * 1000 * Description: 1001 * Avoid trivial tunneling loop by checking that tunnel exit-point 1002 * doesn't match source of incoming packet. 1003 * 1004 * Return: 1005 * 1 if conflict, 1006 * 0 else 1007 **/ 1008 1009 static inline bool 1010 ip6_tnl_addr_conflict(const struct ip6_tnl *t, const struct ipv6hdr *hdr) 1011 { 1012 return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr); 1013 } 1014 1015 int ip6_tnl_xmit_ctl(struct ip6_tnl *t, 1016 const struct in6_addr *laddr, 1017 const struct in6_addr *raddr) 1018 { 1019 struct __ip6_tnl_parm *p = &t->parms; 1020 int ret = 0; 1021 struct net *net = t->net; 1022 1023 if (t->parms.collect_md) 1024 return 1; 1025 1026 if ((p->flags & IP6_TNL_F_CAP_XMIT) || 1027 ((p->flags & IP6_TNL_F_CAP_PER_PACKET) && 1028 (ip6_tnl_get_cap(t, laddr, raddr) & IP6_TNL_F_CAP_XMIT))) { 1029 struct net_device *ldev = NULL; 1030 1031 rcu_read_lock(); 1032 if (p->link) 1033 ldev = dev_get_by_index_rcu(net, p->link); 1034 1035 if (unlikely(!ipv6_chk_addr_and_flags(net, laddr, ldev, false, 1036 0, IFA_F_TENTATIVE))) 1037 pr_warn_ratelimited("%s xmit: Local address not yet configured!\n", 1038 p->name); 1039 else if (!(p->flags & IP6_TNL_F_ALLOW_LOCAL_REMOTE) && 1040 !ipv6_addr_is_multicast(raddr) && 1041 unlikely(ipv6_chk_addr_and_flags(net, raddr, ldev, 1042 true, 0, IFA_F_TENTATIVE))) 1043 pr_warn_ratelimited("%s xmit: Routing loop! Remote address found on this node!\n", 1044 p->name); 1045 else 1046 ret = 1; 1047 rcu_read_unlock(); 1048 } 1049 return ret; 1050 } 1051 EXPORT_SYMBOL_GPL(ip6_tnl_xmit_ctl); 1052 1053 /** 1054 * ip6_tnl_xmit - encapsulate packet and send 1055 * @skb: the outgoing socket buffer 1056 * @dev: the outgoing tunnel device 1057 * @dsfield: dscp code for outer header 1058 * @fl6: flow of tunneled packet 1059 * @encap_limit: encapsulation limit 1060 * @pmtu: Path MTU is stored if packet is too big 1061 * @proto: next header value 1062 * 1063 * Description: 1064 * Build new header and do some sanity checks on the packet before sending 1065 * it. 1066 * 1067 * Return: 1068 * 0 on success 1069 * -1 fail 1070 * %-EMSGSIZE message too big. return mtu in this case. 1071 **/ 1072 1073 int ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev, __u8 dsfield, 1074 struct flowi6 *fl6, int encap_limit, __u32 *pmtu, 1075 __u8 proto) 1076 { 1077 struct ip6_tnl *t = netdev_priv(dev); 1078 struct net *net = t->net; 1079 struct net_device_stats *stats = &t->dev->stats; 1080 struct ipv6hdr *ipv6h; 1081 struct ipv6_tel_txoption opt; 1082 struct dst_entry *dst = NULL, *ndst = NULL; 1083 struct net_device *tdev; 1084 int mtu; 1085 unsigned int eth_hlen = t->dev->type == ARPHRD_ETHER ? ETH_HLEN : 0; 1086 unsigned int psh_hlen = sizeof(struct ipv6hdr) + t->encap_hlen; 1087 unsigned int max_headroom = psh_hlen; 1088 bool use_cache = false; 1089 u8 hop_limit; 1090 int err = -1; 1091 1092 if (t->parms.collect_md) { 1093 hop_limit = skb_tunnel_info(skb)->key.ttl; 1094 goto route_lookup; 1095 } else { 1096 hop_limit = t->parms.hop_limit; 1097 } 1098 1099 /* NBMA tunnel */ 1100 if (ipv6_addr_any(&t->parms.raddr)) { 1101 if (skb->protocol == htons(ETH_P_IPV6)) { 1102 struct in6_addr *addr6; 1103 struct neighbour *neigh; 1104 int addr_type; 1105 1106 if (!skb_dst(skb)) 1107 goto tx_err_link_failure; 1108 1109 neigh = dst_neigh_lookup(skb_dst(skb), 1110 &ipv6_hdr(skb)->daddr); 1111 if (!neigh) 1112 goto tx_err_link_failure; 1113 1114 addr6 = (struct in6_addr *)&neigh->primary_key; 1115 addr_type = ipv6_addr_type(addr6); 1116 1117 if (addr_type == IPV6_ADDR_ANY) 1118 addr6 = &ipv6_hdr(skb)->daddr; 1119 1120 memcpy(&fl6->daddr, addr6, sizeof(fl6->daddr)); 1121 neigh_release(neigh); 1122 } else if (skb->protocol == htons(ETH_P_IP)) { 1123 const struct rtable *rt = skb_rtable(skb); 1124 1125 if (!rt) 1126 goto tx_err_link_failure; 1127 1128 if (rt->rt_gw_family == AF_INET6) 1129 memcpy(&fl6->daddr, &rt->rt_gw6, sizeof(fl6->daddr)); 1130 } 1131 } else if (t->parms.proto != 0 && !(t->parms.flags & 1132 (IP6_TNL_F_USE_ORIG_TCLASS | 1133 IP6_TNL_F_USE_ORIG_FWMARK))) { 1134 /* enable the cache only if neither the outer protocol nor the 1135 * routing decision depends on the current inner header value 1136 */ 1137 use_cache = true; 1138 } 1139 1140 if (use_cache) 1141 dst = dst_cache_get(&t->dst_cache); 1142 1143 if (!ip6_tnl_xmit_ctl(t, &fl6->saddr, &fl6->daddr)) 1144 goto tx_err_link_failure; 1145 1146 if (!dst) { 1147 route_lookup: 1148 /* add dsfield to flowlabel for route lookup */ 1149 fl6->flowlabel = ip6_make_flowinfo(dsfield, fl6->flowlabel); 1150 1151 dst = ip6_route_output(net, NULL, fl6); 1152 1153 if (dst->error) 1154 goto tx_err_link_failure; 1155 dst = xfrm_lookup(net, dst, flowi6_to_flowi(fl6), NULL, 0); 1156 if (IS_ERR(dst)) { 1157 err = PTR_ERR(dst); 1158 dst = NULL; 1159 goto tx_err_link_failure; 1160 } 1161 if (t->parms.collect_md && ipv6_addr_any(&fl6->saddr) && 1162 ipv6_dev_get_saddr(net, ip6_dst_idev(dst)->dev, 1163 &fl6->daddr, 0, &fl6->saddr)) 1164 goto tx_err_link_failure; 1165 ndst = dst; 1166 } 1167 1168 tdev = dst->dev; 1169 1170 if (tdev == dev) { 1171 stats->collisions++; 1172 net_warn_ratelimited("%s: Local routing loop detected!\n", 1173 t->parms.name); 1174 goto tx_err_dst_release; 1175 } 1176 mtu = dst_mtu(dst) - eth_hlen - psh_hlen - t->tun_hlen; 1177 if (encap_limit >= 0) { 1178 max_headroom += 8; 1179 mtu -= 8; 1180 } 1181 mtu = max(mtu, skb->protocol == htons(ETH_P_IPV6) ? 1182 IPV6_MIN_MTU : IPV4_MIN_MTU); 1183 1184 skb_dst_update_pmtu_no_confirm(skb, mtu); 1185 if (skb->len - t->tun_hlen - eth_hlen > mtu && !skb_is_gso(skb)) { 1186 *pmtu = mtu; 1187 err = -EMSGSIZE; 1188 goto tx_err_dst_release; 1189 } 1190 1191 if (t->err_count > 0) { 1192 if (time_before(jiffies, 1193 t->err_time + IP6TUNNEL_ERR_TIMEO)) { 1194 t->err_count--; 1195 1196 dst_link_failure(skb); 1197 } else { 1198 t->err_count = 0; 1199 } 1200 } 1201 1202 skb_scrub_packet(skb, !net_eq(t->net, dev_net(dev))); 1203 1204 /* 1205 * Okay, now see if we can stuff it in the buffer as-is. 1206 */ 1207 max_headroom += LL_RESERVED_SPACE(tdev); 1208 1209 if (skb_headroom(skb) < max_headroom || skb_shared(skb) || 1210 (skb_cloned(skb) && !skb_clone_writable(skb, 0))) { 1211 struct sk_buff *new_skb; 1212 1213 new_skb = skb_realloc_headroom(skb, max_headroom); 1214 if (!new_skb) 1215 goto tx_err_dst_release; 1216 1217 if (skb->sk) 1218 skb_set_owner_w(new_skb, skb->sk); 1219 consume_skb(skb); 1220 skb = new_skb; 1221 } 1222 1223 if (t->parms.collect_md) { 1224 if (t->encap.type != TUNNEL_ENCAP_NONE) 1225 goto tx_err_dst_release; 1226 } else { 1227 if (use_cache && ndst) 1228 dst_cache_set_ip6(&t->dst_cache, ndst, &fl6->saddr); 1229 } 1230 skb_dst_set(skb, dst); 1231 1232 if (hop_limit == 0) { 1233 if (skb->protocol == htons(ETH_P_IP)) 1234 hop_limit = ip_hdr(skb)->ttl; 1235 else if (skb->protocol == htons(ETH_P_IPV6)) 1236 hop_limit = ipv6_hdr(skb)->hop_limit; 1237 else 1238 hop_limit = ip6_dst_hoplimit(dst); 1239 } 1240 1241 /* Calculate max headroom for all the headers and adjust 1242 * needed_headroom if necessary. 1243 */ 1244 max_headroom = LL_RESERVED_SPACE(dst->dev) + sizeof(struct ipv6hdr) 1245 + dst->header_len + t->hlen; 1246 if (max_headroom > dev->needed_headroom) 1247 dev->needed_headroom = max_headroom; 1248 1249 err = ip6_tnl_encap(skb, t, &proto, fl6); 1250 if (err) 1251 return err; 1252 1253 if (encap_limit >= 0) { 1254 init_tel_txopt(&opt, encap_limit); 1255 ipv6_push_frag_opts(skb, &opt.ops, &proto); 1256 } 1257 1258 skb_push(skb, sizeof(struct ipv6hdr)); 1259 skb_reset_network_header(skb); 1260 ipv6h = ipv6_hdr(skb); 1261 ip6_flow_hdr(ipv6h, dsfield, 1262 ip6_make_flowlabel(net, skb, fl6->flowlabel, true, fl6)); 1263 ipv6h->hop_limit = hop_limit; 1264 ipv6h->nexthdr = proto; 1265 ipv6h->saddr = fl6->saddr; 1266 ipv6h->daddr = fl6->daddr; 1267 ip6tunnel_xmit(NULL, skb, dev); 1268 return 0; 1269 tx_err_link_failure: 1270 stats->tx_carrier_errors++; 1271 dst_link_failure(skb); 1272 tx_err_dst_release: 1273 dst_release(dst); 1274 return err; 1275 } 1276 EXPORT_SYMBOL(ip6_tnl_xmit); 1277 1278 static inline int 1279 ipxip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev, 1280 u8 protocol) 1281 { 1282 struct ip6_tnl *t = netdev_priv(dev); 1283 struct ipv6hdr *ipv6h; 1284 const struct iphdr *iph; 1285 int encap_limit = -1; 1286 __u16 offset; 1287 struct flowi6 fl6; 1288 __u8 dsfield, orig_dsfield; 1289 __u32 mtu; 1290 u8 tproto; 1291 int err; 1292 1293 tproto = READ_ONCE(t->parms.proto); 1294 if (tproto != protocol && tproto != 0) 1295 return -1; 1296 1297 if (t->parms.collect_md) { 1298 struct ip_tunnel_info *tun_info; 1299 const struct ip_tunnel_key *key; 1300 1301 tun_info = skb_tunnel_info(skb); 1302 if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) || 1303 ip_tunnel_info_af(tun_info) != AF_INET6)) 1304 return -1; 1305 key = &tun_info->key; 1306 memset(&fl6, 0, sizeof(fl6)); 1307 fl6.flowi6_proto = protocol; 1308 fl6.saddr = key->u.ipv6.src; 1309 fl6.daddr = key->u.ipv6.dst; 1310 fl6.flowlabel = key->label; 1311 dsfield = key->tos; 1312 switch (protocol) { 1313 case IPPROTO_IPIP: 1314 iph = ip_hdr(skb); 1315 orig_dsfield = ipv4_get_dsfield(iph); 1316 break; 1317 case IPPROTO_IPV6: 1318 ipv6h = ipv6_hdr(skb); 1319 orig_dsfield = ipv6_get_dsfield(ipv6h); 1320 break; 1321 default: 1322 orig_dsfield = dsfield; 1323 break; 1324 } 1325 } else { 1326 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1327 encap_limit = t->parms.encap_limit; 1328 if (protocol == IPPROTO_IPV6) { 1329 offset = ip6_tnl_parse_tlv_enc_lim(skb, 1330 skb_network_header(skb)); 1331 /* ip6_tnl_parse_tlv_enc_lim() might have 1332 * reallocated skb->head 1333 */ 1334 if (offset > 0) { 1335 struct ipv6_tlv_tnl_enc_lim *tel; 1336 1337 tel = (void *)&skb_network_header(skb)[offset]; 1338 if (tel->encap_limit == 0) { 1339 icmpv6_ndo_send(skb, ICMPV6_PARAMPROB, 1340 ICMPV6_HDR_FIELD, offset + 2); 1341 return -1; 1342 } 1343 encap_limit = tel->encap_limit - 1; 1344 } 1345 } 1346 1347 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 1348 fl6.flowi6_proto = protocol; 1349 1350 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK) 1351 fl6.flowi6_mark = skb->mark; 1352 else 1353 fl6.flowi6_mark = t->parms.fwmark; 1354 switch (protocol) { 1355 case IPPROTO_IPIP: 1356 iph = ip_hdr(skb); 1357 orig_dsfield = ipv4_get_dsfield(iph); 1358 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) 1359 dsfield = orig_dsfield; 1360 else 1361 dsfield = ip6_tclass(t->parms.flowinfo); 1362 break; 1363 case IPPROTO_IPV6: 1364 ipv6h = ipv6_hdr(skb); 1365 orig_dsfield = ipv6_get_dsfield(ipv6h); 1366 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) 1367 dsfield = orig_dsfield; 1368 else 1369 dsfield = ip6_tclass(t->parms.flowinfo); 1370 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL) 1371 fl6.flowlabel |= ip6_flowlabel(ipv6h); 1372 break; 1373 default: 1374 orig_dsfield = dsfield = ip6_tclass(t->parms.flowinfo); 1375 break; 1376 } 1377 } 1378 1379 fl6.flowi6_uid = sock_net_uid(dev_net(dev), NULL); 1380 dsfield = INET_ECN_encapsulate(dsfield, orig_dsfield); 1381 1382 if (iptunnel_handle_offloads(skb, SKB_GSO_IPXIP6)) 1383 return -1; 1384 1385 skb_set_inner_ipproto(skb, protocol); 1386 1387 err = ip6_tnl_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu, 1388 protocol); 1389 if (err != 0) { 1390 /* XXX: send ICMP error even if DF is not set. */ 1391 if (err == -EMSGSIZE) 1392 switch (protocol) { 1393 case IPPROTO_IPIP: 1394 icmp_ndo_send(skb, ICMP_DEST_UNREACH, 1395 ICMP_FRAG_NEEDED, htonl(mtu)); 1396 break; 1397 case IPPROTO_IPV6: 1398 icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); 1399 break; 1400 default: 1401 break; 1402 } 1403 return -1; 1404 } 1405 1406 return 0; 1407 } 1408 1409 static netdev_tx_t 1410 ip6_tnl_start_xmit(struct sk_buff *skb, struct net_device *dev) 1411 { 1412 struct ip6_tnl *t = netdev_priv(dev); 1413 struct net_device_stats *stats = &t->dev->stats; 1414 u8 ipproto; 1415 int ret; 1416 1417 if (!pskb_inet_may_pull(skb)) 1418 goto tx_err; 1419 1420 switch (skb->protocol) { 1421 case htons(ETH_P_IP): 1422 ipproto = IPPROTO_IPIP; 1423 break; 1424 case htons(ETH_P_IPV6): 1425 if (ip6_tnl_addr_conflict(t, ipv6_hdr(skb))) 1426 goto tx_err; 1427 ipproto = IPPROTO_IPV6; 1428 break; 1429 case htons(ETH_P_MPLS_UC): 1430 ipproto = IPPROTO_MPLS; 1431 break; 1432 default: 1433 goto tx_err; 1434 } 1435 1436 ret = ipxip6_tnl_xmit(skb, dev, ipproto); 1437 if (ret < 0) 1438 goto tx_err; 1439 1440 return NETDEV_TX_OK; 1441 1442 tx_err: 1443 stats->tx_errors++; 1444 stats->tx_dropped++; 1445 kfree_skb(skb); 1446 return NETDEV_TX_OK; 1447 } 1448 1449 static void ip6_tnl_link_config(struct ip6_tnl *t) 1450 { 1451 struct net_device *dev = t->dev; 1452 struct net_device *tdev = NULL; 1453 struct __ip6_tnl_parm *p = &t->parms; 1454 struct flowi6 *fl6 = &t->fl.u.ip6; 1455 unsigned int mtu; 1456 int t_hlen; 1457 1458 __dev_addr_set(dev, &p->laddr, sizeof(struct in6_addr)); 1459 memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr)); 1460 1461 /* Set up flowi template */ 1462 fl6->saddr = p->laddr; 1463 fl6->daddr = p->raddr; 1464 fl6->flowi6_oif = p->link; 1465 fl6->flowlabel = 0; 1466 1467 if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS)) 1468 fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo; 1469 if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL)) 1470 fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo; 1471 1472 p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET); 1473 p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr); 1474 1475 if (p->flags&IP6_TNL_F_CAP_XMIT && p->flags&IP6_TNL_F_CAP_RCV) 1476 dev->flags |= IFF_POINTOPOINT; 1477 else 1478 dev->flags &= ~IFF_POINTOPOINT; 1479 1480 t->tun_hlen = 0; 1481 t->hlen = t->encap_hlen + t->tun_hlen; 1482 t_hlen = t->hlen + sizeof(struct ipv6hdr); 1483 1484 if (p->flags & IP6_TNL_F_CAP_XMIT) { 1485 int strict = (ipv6_addr_type(&p->raddr) & 1486 (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL)); 1487 1488 struct rt6_info *rt = rt6_lookup(t->net, 1489 &p->raddr, &p->laddr, 1490 p->link, NULL, strict); 1491 if (rt) { 1492 tdev = rt->dst.dev; 1493 ip6_rt_put(rt); 1494 } 1495 1496 if (!tdev && p->link) 1497 tdev = __dev_get_by_index(t->net, p->link); 1498 1499 if (tdev) { 1500 dev->hard_header_len = tdev->hard_header_len + t_hlen; 1501 mtu = min_t(unsigned int, tdev->mtu, IP6_MAX_MTU); 1502 1503 dev->mtu = mtu - t_hlen; 1504 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1505 dev->mtu -= 8; 1506 1507 if (dev->mtu < IPV6_MIN_MTU) 1508 dev->mtu = IPV6_MIN_MTU; 1509 } 1510 } 1511 } 1512 1513 /** 1514 * ip6_tnl_change - update the tunnel parameters 1515 * @t: tunnel to be changed 1516 * @p: tunnel configuration parameters 1517 * 1518 * Description: 1519 * ip6_tnl_change() updates the tunnel parameters 1520 **/ 1521 1522 static int 1523 ip6_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p) 1524 { 1525 t->parms.laddr = p->laddr; 1526 t->parms.raddr = p->raddr; 1527 t->parms.flags = p->flags; 1528 t->parms.hop_limit = p->hop_limit; 1529 t->parms.encap_limit = p->encap_limit; 1530 t->parms.flowinfo = p->flowinfo; 1531 t->parms.link = p->link; 1532 t->parms.proto = p->proto; 1533 t->parms.fwmark = p->fwmark; 1534 dst_cache_reset(&t->dst_cache); 1535 ip6_tnl_link_config(t); 1536 return 0; 1537 } 1538 1539 static int ip6_tnl_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p) 1540 { 1541 struct net *net = t->net; 1542 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1543 int err; 1544 1545 ip6_tnl_unlink(ip6n, t); 1546 synchronize_net(); 1547 err = ip6_tnl_change(t, p); 1548 ip6_tnl_link(ip6n, t); 1549 netdev_state_change(t->dev); 1550 return err; 1551 } 1552 1553 static int ip6_tnl0_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p) 1554 { 1555 /* for default tnl0 device allow to change only the proto */ 1556 t->parms.proto = p->proto; 1557 netdev_state_change(t->dev); 1558 return 0; 1559 } 1560 1561 static void 1562 ip6_tnl_parm_from_user(struct __ip6_tnl_parm *p, const struct ip6_tnl_parm *u) 1563 { 1564 p->laddr = u->laddr; 1565 p->raddr = u->raddr; 1566 p->flags = u->flags; 1567 p->hop_limit = u->hop_limit; 1568 p->encap_limit = u->encap_limit; 1569 p->flowinfo = u->flowinfo; 1570 p->link = u->link; 1571 p->proto = u->proto; 1572 memcpy(p->name, u->name, sizeof(u->name)); 1573 } 1574 1575 static void 1576 ip6_tnl_parm_to_user(struct ip6_tnl_parm *u, const struct __ip6_tnl_parm *p) 1577 { 1578 u->laddr = p->laddr; 1579 u->raddr = p->raddr; 1580 u->flags = p->flags; 1581 u->hop_limit = p->hop_limit; 1582 u->encap_limit = p->encap_limit; 1583 u->flowinfo = p->flowinfo; 1584 u->link = p->link; 1585 u->proto = p->proto; 1586 memcpy(u->name, p->name, sizeof(u->name)); 1587 } 1588 1589 /** 1590 * ip6_tnl_siocdevprivate - configure ipv6 tunnels from userspace 1591 * @dev: virtual device associated with tunnel 1592 * @ifr: unused 1593 * @data: parameters passed from userspace 1594 * @cmd: command to be performed 1595 * 1596 * Description: 1597 * ip6_tnl_ioctl() is used for managing IPv6 tunnels 1598 * from userspace. 1599 * 1600 * The possible commands are the following: 1601 * %SIOCGETTUNNEL: get tunnel parameters for device 1602 * %SIOCADDTUNNEL: add tunnel matching given tunnel parameters 1603 * %SIOCCHGTUNNEL: change tunnel parameters to those given 1604 * %SIOCDELTUNNEL: delete tunnel 1605 * 1606 * The fallback device "ip6tnl0", created during module 1607 * initialization, can be used for creating other tunnel devices. 1608 * 1609 * Return: 1610 * 0 on success, 1611 * %-EFAULT if unable to copy data to or from userspace, 1612 * %-EPERM if current process hasn't %CAP_NET_ADMIN set 1613 * %-EINVAL if passed tunnel parameters are invalid, 1614 * %-EEXIST if changing a tunnel's parameters would cause a conflict 1615 * %-ENODEV if attempting to change or delete a nonexisting device 1616 **/ 1617 1618 static int 1619 ip6_tnl_siocdevprivate(struct net_device *dev, struct ifreq *ifr, 1620 void __user *data, int cmd) 1621 { 1622 int err = 0; 1623 struct ip6_tnl_parm p; 1624 struct __ip6_tnl_parm p1; 1625 struct ip6_tnl *t = netdev_priv(dev); 1626 struct net *net = t->net; 1627 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1628 1629 memset(&p1, 0, sizeof(p1)); 1630 1631 switch (cmd) { 1632 case SIOCGETTUNNEL: 1633 if (dev == ip6n->fb_tnl_dev) { 1634 if (copy_from_user(&p, data, sizeof(p))) { 1635 err = -EFAULT; 1636 break; 1637 } 1638 ip6_tnl_parm_from_user(&p1, &p); 1639 t = ip6_tnl_locate(net, &p1, 0); 1640 if (IS_ERR(t)) 1641 t = netdev_priv(dev); 1642 } else { 1643 memset(&p, 0, sizeof(p)); 1644 } 1645 ip6_tnl_parm_to_user(&p, &t->parms); 1646 if (copy_to_user(data, &p, sizeof(p))) 1647 err = -EFAULT; 1648 break; 1649 case SIOCADDTUNNEL: 1650 case SIOCCHGTUNNEL: 1651 err = -EPERM; 1652 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 1653 break; 1654 err = -EFAULT; 1655 if (copy_from_user(&p, data, sizeof(p))) 1656 break; 1657 err = -EINVAL; 1658 if (p.proto != IPPROTO_IPV6 && p.proto != IPPROTO_IPIP && 1659 p.proto != 0) 1660 break; 1661 ip6_tnl_parm_from_user(&p1, &p); 1662 t = ip6_tnl_locate(net, &p1, cmd == SIOCADDTUNNEL); 1663 if (cmd == SIOCCHGTUNNEL) { 1664 if (!IS_ERR(t)) { 1665 if (t->dev != dev) { 1666 err = -EEXIST; 1667 break; 1668 } 1669 } else 1670 t = netdev_priv(dev); 1671 if (dev == ip6n->fb_tnl_dev) 1672 err = ip6_tnl0_update(t, &p1); 1673 else 1674 err = ip6_tnl_update(t, &p1); 1675 } 1676 if (!IS_ERR(t)) { 1677 err = 0; 1678 ip6_tnl_parm_to_user(&p, &t->parms); 1679 if (copy_to_user(data, &p, sizeof(p))) 1680 err = -EFAULT; 1681 1682 } else { 1683 err = PTR_ERR(t); 1684 } 1685 break; 1686 case SIOCDELTUNNEL: 1687 err = -EPERM; 1688 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 1689 break; 1690 1691 if (dev == ip6n->fb_tnl_dev) { 1692 err = -EFAULT; 1693 if (copy_from_user(&p, data, sizeof(p))) 1694 break; 1695 err = -ENOENT; 1696 ip6_tnl_parm_from_user(&p1, &p); 1697 t = ip6_tnl_locate(net, &p1, 0); 1698 if (IS_ERR(t)) 1699 break; 1700 err = -EPERM; 1701 if (t->dev == ip6n->fb_tnl_dev) 1702 break; 1703 dev = t->dev; 1704 } 1705 err = 0; 1706 unregister_netdevice(dev); 1707 break; 1708 default: 1709 err = -EINVAL; 1710 } 1711 return err; 1712 } 1713 1714 /** 1715 * ip6_tnl_change_mtu - change mtu manually for tunnel device 1716 * @dev: virtual device associated with tunnel 1717 * @new_mtu: the new mtu 1718 * 1719 * Return: 1720 * 0 on success, 1721 * %-EINVAL if mtu too small 1722 **/ 1723 1724 int ip6_tnl_change_mtu(struct net_device *dev, int new_mtu) 1725 { 1726 struct ip6_tnl *tnl = netdev_priv(dev); 1727 1728 if (tnl->parms.proto == IPPROTO_IPV6) { 1729 if (new_mtu < IPV6_MIN_MTU) 1730 return -EINVAL; 1731 } else { 1732 if (new_mtu < ETH_MIN_MTU) 1733 return -EINVAL; 1734 } 1735 if (tnl->parms.proto == IPPROTO_IPV6 || tnl->parms.proto == 0) { 1736 if (new_mtu > IP6_MAX_MTU - dev->hard_header_len) 1737 return -EINVAL; 1738 } else { 1739 if (new_mtu > IP_MAX_MTU - dev->hard_header_len) 1740 return -EINVAL; 1741 } 1742 dev->mtu = new_mtu; 1743 return 0; 1744 } 1745 EXPORT_SYMBOL(ip6_tnl_change_mtu); 1746 1747 int ip6_tnl_get_iflink(const struct net_device *dev) 1748 { 1749 struct ip6_tnl *t = netdev_priv(dev); 1750 1751 return t->parms.link; 1752 } 1753 EXPORT_SYMBOL(ip6_tnl_get_iflink); 1754 1755 int ip6_tnl_encap_add_ops(const struct ip6_tnl_encap_ops *ops, 1756 unsigned int num) 1757 { 1758 if (num >= MAX_IPTUN_ENCAP_OPS) 1759 return -ERANGE; 1760 1761 return !cmpxchg((const struct ip6_tnl_encap_ops **) 1762 &ip6tun_encaps[num], 1763 NULL, ops) ? 0 : -1; 1764 } 1765 EXPORT_SYMBOL(ip6_tnl_encap_add_ops); 1766 1767 int ip6_tnl_encap_del_ops(const struct ip6_tnl_encap_ops *ops, 1768 unsigned int num) 1769 { 1770 int ret; 1771 1772 if (num >= MAX_IPTUN_ENCAP_OPS) 1773 return -ERANGE; 1774 1775 ret = (cmpxchg((const struct ip6_tnl_encap_ops **) 1776 &ip6tun_encaps[num], 1777 ops, NULL) == ops) ? 0 : -1; 1778 1779 synchronize_net(); 1780 1781 return ret; 1782 } 1783 EXPORT_SYMBOL(ip6_tnl_encap_del_ops); 1784 1785 int ip6_tnl_encap_setup(struct ip6_tnl *t, 1786 struct ip_tunnel_encap *ipencap) 1787 { 1788 int hlen; 1789 1790 memset(&t->encap, 0, sizeof(t->encap)); 1791 1792 hlen = ip6_encap_hlen(ipencap); 1793 if (hlen < 0) 1794 return hlen; 1795 1796 t->encap.type = ipencap->type; 1797 t->encap.sport = ipencap->sport; 1798 t->encap.dport = ipencap->dport; 1799 t->encap.flags = ipencap->flags; 1800 1801 t->encap_hlen = hlen; 1802 t->hlen = t->encap_hlen + t->tun_hlen; 1803 1804 return 0; 1805 } 1806 EXPORT_SYMBOL_GPL(ip6_tnl_encap_setup); 1807 1808 static const struct net_device_ops ip6_tnl_netdev_ops = { 1809 .ndo_init = ip6_tnl_dev_init, 1810 .ndo_uninit = ip6_tnl_dev_uninit, 1811 .ndo_start_xmit = ip6_tnl_start_xmit, 1812 .ndo_siocdevprivate = ip6_tnl_siocdevprivate, 1813 .ndo_change_mtu = ip6_tnl_change_mtu, 1814 .ndo_get_stats64 = dev_get_tstats64, 1815 .ndo_get_iflink = ip6_tnl_get_iflink, 1816 }; 1817 1818 #define IPXIPX_FEATURES (NETIF_F_SG | \ 1819 NETIF_F_FRAGLIST | \ 1820 NETIF_F_HIGHDMA | \ 1821 NETIF_F_GSO_SOFTWARE | \ 1822 NETIF_F_HW_CSUM) 1823 1824 /** 1825 * ip6_tnl_dev_setup - setup virtual tunnel device 1826 * @dev: virtual device associated with tunnel 1827 * 1828 * Description: 1829 * Initialize function pointers and device parameters 1830 **/ 1831 1832 static void ip6_tnl_dev_setup(struct net_device *dev) 1833 { 1834 dev->netdev_ops = &ip6_tnl_netdev_ops; 1835 dev->header_ops = &ip_tunnel_header_ops; 1836 dev->needs_free_netdev = true; 1837 dev->priv_destructor = ip6_dev_free; 1838 1839 dev->type = ARPHRD_TUNNEL6; 1840 dev->flags |= IFF_NOARP; 1841 dev->addr_len = sizeof(struct in6_addr); 1842 dev->features |= NETIF_F_LLTX; 1843 netif_keep_dst(dev); 1844 1845 dev->features |= IPXIPX_FEATURES; 1846 dev->hw_features |= IPXIPX_FEATURES; 1847 1848 /* This perm addr will be used as interface identifier by IPv6 */ 1849 dev->addr_assign_type = NET_ADDR_RANDOM; 1850 eth_random_addr(dev->perm_addr); 1851 } 1852 1853 1854 /** 1855 * ip6_tnl_dev_init_gen - general initializer for all tunnel devices 1856 * @dev: virtual device associated with tunnel 1857 **/ 1858 1859 static inline int 1860 ip6_tnl_dev_init_gen(struct net_device *dev) 1861 { 1862 struct ip6_tnl *t = netdev_priv(dev); 1863 int ret; 1864 int t_hlen; 1865 1866 t->dev = dev; 1867 t->net = dev_net(dev); 1868 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats); 1869 if (!dev->tstats) 1870 return -ENOMEM; 1871 1872 ret = dst_cache_init(&t->dst_cache, GFP_KERNEL); 1873 if (ret) 1874 goto free_stats; 1875 1876 ret = gro_cells_init(&t->gro_cells, dev); 1877 if (ret) 1878 goto destroy_dst; 1879 1880 t->tun_hlen = 0; 1881 t->hlen = t->encap_hlen + t->tun_hlen; 1882 t_hlen = t->hlen + sizeof(struct ipv6hdr); 1883 1884 dev->type = ARPHRD_TUNNEL6; 1885 dev->hard_header_len = LL_MAX_HEADER + t_hlen; 1886 dev->mtu = ETH_DATA_LEN - t_hlen; 1887 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1888 dev->mtu -= 8; 1889 dev->min_mtu = ETH_MIN_MTU; 1890 dev->max_mtu = IP6_MAX_MTU - dev->hard_header_len; 1891 1892 dev_hold_track(dev, &t->dev_tracker, GFP_KERNEL); 1893 return 0; 1894 1895 destroy_dst: 1896 dst_cache_destroy(&t->dst_cache); 1897 free_stats: 1898 free_percpu(dev->tstats); 1899 dev->tstats = NULL; 1900 1901 return ret; 1902 } 1903 1904 /** 1905 * ip6_tnl_dev_init - initializer for all non fallback tunnel devices 1906 * @dev: virtual device associated with tunnel 1907 **/ 1908 1909 static int ip6_tnl_dev_init(struct net_device *dev) 1910 { 1911 struct ip6_tnl *t = netdev_priv(dev); 1912 int err = ip6_tnl_dev_init_gen(dev); 1913 1914 if (err) 1915 return err; 1916 ip6_tnl_link_config(t); 1917 if (t->parms.collect_md) 1918 netif_keep_dst(dev); 1919 return 0; 1920 } 1921 1922 /** 1923 * ip6_fb_tnl_dev_init - initializer for fallback tunnel device 1924 * @dev: fallback device 1925 * 1926 * Return: 0 1927 **/ 1928 1929 static int __net_init ip6_fb_tnl_dev_init(struct net_device *dev) 1930 { 1931 struct ip6_tnl *t = netdev_priv(dev); 1932 struct net *net = dev_net(dev); 1933 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1934 1935 t->parms.proto = IPPROTO_IPV6; 1936 1937 rcu_assign_pointer(ip6n->tnls_wc[0], t); 1938 return 0; 1939 } 1940 1941 static int ip6_tnl_validate(struct nlattr *tb[], struct nlattr *data[], 1942 struct netlink_ext_ack *extack) 1943 { 1944 u8 proto; 1945 1946 if (!data || !data[IFLA_IPTUN_PROTO]) 1947 return 0; 1948 1949 proto = nla_get_u8(data[IFLA_IPTUN_PROTO]); 1950 if (proto != IPPROTO_IPV6 && 1951 proto != IPPROTO_IPIP && 1952 proto != 0) 1953 return -EINVAL; 1954 1955 return 0; 1956 } 1957 1958 static void ip6_tnl_netlink_parms(struct nlattr *data[], 1959 struct __ip6_tnl_parm *parms) 1960 { 1961 memset(parms, 0, sizeof(*parms)); 1962 1963 if (!data) 1964 return; 1965 1966 if (data[IFLA_IPTUN_LINK]) 1967 parms->link = nla_get_u32(data[IFLA_IPTUN_LINK]); 1968 1969 if (data[IFLA_IPTUN_LOCAL]) 1970 parms->laddr = nla_get_in6_addr(data[IFLA_IPTUN_LOCAL]); 1971 1972 if (data[IFLA_IPTUN_REMOTE]) 1973 parms->raddr = nla_get_in6_addr(data[IFLA_IPTUN_REMOTE]); 1974 1975 if (data[IFLA_IPTUN_TTL]) 1976 parms->hop_limit = nla_get_u8(data[IFLA_IPTUN_TTL]); 1977 1978 if (data[IFLA_IPTUN_ENCAP_LIMIT]) 1979 parms->encap_limit = nla_get_u8(data[IFLA_IPTUN_ENCAP_LIMIT]); 1980 1981 if (data[IFLA_IPTUN_FLOWINFO]) 1982 parms->flowinfo = nla_get_be32(data[IFLA_IPTUN_FLOWINFO]); 1983 1984 if (data[IFLA_IPTUN_FLAGS]) 1985 parms->flags = nla_get_u32(data[IFLA_IPTUN_FLAGS]); 1986 1987 if (data[IFLA_IPTUN_PROTO]) 1988 parms->proto = nla_get_u8(data[IFLA_IPTUN_PROTO]); 1989 1990 if (data[IFLA_IPTUN_COLLECT_METADATA]) 1991 parms->collect_md = true; 1992 1993 if (data[IFLA_IPTUN_FWMARK]) 1994 parms->fwmark = nla_get_u32(data[IFLA_IPTUN_FWMARK]); 1995 } 1996 1997 static bool ip6_tnl_netlink_encap_parms(struct nlattr *data[], 1998 struct ip_tunnel_encap *ipencap) 1999 { 2000 bool ret = false; 2001 2002 memset(ipencap, 0, sizeof(*ipencap)); 2003 2004 if (!data) 2005 return ret; 2006 2007 if (data[IFLA_IPTUN_ENCAP_TYPE]) { 2008 ret = true; 2009 ipencap->type = nla_get_u16(data[IFLA_IPTUN_ENCAP_TYPE]); 2010 } 2011 2012 if (data[IFLA_IPTUN_ENCAP_FLAGS]) { 2013 ret = true; 2014 ipencap->flags = nla_get_u16(data[IFLA_IPTUN_ENCAP_FLAGS]); 2015 } 2016 2017 if (data[IFLA_IPTUN_ENCAP_SPORT]) { 2018 ret = true; 2019 ipencap->sport = nla_get_be16(data[IFLA_IPTUN_ENCAP_SPORT]); 2020 } 2021 2022 if (data[IFLA_IPTUN_ENCAP_DPORT]) { 2023 ret = true; 2024 ipencap->dport = nla_get_be16(data[IFLA_IPTUN_ENCAP_DPORT]); 2025 } 2026 2027 return ret; 2028 } 2029 2030 static int ip6_tnl_newlink(struct net *src_net, struct net_device *dev, 2031 struct nlattr *tb[], struct nlattr *data[], 2032 struct netlink_ext_ack *extack) 2033 { 2034 struct net *net = dev_net(dev); 2035 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 2036 struct ip_tunnel_encap ipencap; 2037 struct ip6_tnl *nt, *t; 2038 int err; 2039 2040 nt = netdev_priv(dev); 2041 2042 if (ip6_tnl_netlink_encap_parms(data, &ipencap)) { 2043 err = ip6_tnl_encap_setup(nt, &ipencap); 2044 if (err < 0) 2045 return err; 2046 } 2047 2048 ip6_tnl_netlink_parms(data, &nt->parms); 2049 2050 if (nt->parms.collect_md) { 2051 if (rtnl_dereference(ip6n->collect_md_tun)) 2052 return -EEXIST; 2053 } else { 2054 t = ip6_tnl_locate(net, &nt->parms, 0); 2055 if (!IS_ERR(t)) 2056 return -EEXIST; 2057 } 2058 2059 err = ip6_tnl_create2(dev); 2060 if (!err && tb[IFLA_MTU]) 2061 ip6_tnl_change_mtu(dev, nla_get_u32(tb[IFLA_MTU])); 2062 2063 return err; 2064 } 2065 2066 static int ip6_tnl_changelink(struct net_device *dev, struct nlattr *tb[], 2067 struct nlattr *data[], 2068 struct netlink_ext_ack *extack) 2069 { 2070 struct ip6_tnl *t = netdev_priv(dev); 2071 struct __ip6_tnl_parm p; 2072 struct net *net = t->net; 2073 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 2074 struct ip_tunnel_encap ipencap; 2075 2076 if (dev == ip6n->fb_tnl_dev) 2077 return -EINVAL; 2078 2079 if (ip6_tnl_netlink_encap_parms(data, &ipencap)) { 2080 int err = ip6_tnl_encap_setup(t, &ipencap); 2081 2082 if (err < 0) 2083 return err; 2084 } 2085 ip6_tnl_netlink_parms(data, &p); 2086 if (p.collect_md) 2087 return -EINVAL; 2088 2089 t = ip6_tnl_locate(net, &p, 0); 2090 if (!IS_ERR(t)) { 2091 if (t->dev != dev) 2092 return -EEXIST; 2093 } else 2094 t = netdev_priv(dev); 2095 2096 return ip6_tnl_update(t, &p); 2097 } 2098 2099 static void ip6_tnl_dellink(struct net_device *dev, struct list_head *head) 2100 { 2101 struct net *net = dev_net(dev); 2102 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 2103 2104 if (dev != ip6n->fb_tnl_dev) 2105 unregister_netdevice_queue(dev, head); 2106 } 2107 2108 static size_t ip6_tnl_get_size(const struct net_device *dev) 2109 { 2110 return 2111 /* IFLA_IPTUN_LINK */ 2112 nla_total_size(4) + 2113 /* IFLA_IPTUN_LOCAL */ 2114 nla_total_size(sizeof(struct in6_addr)) + 2115 /* IFLA_IPTUN_REMOTE */ 2116 nla_total_size(sizeof(struct in6_addr)) + 2117 /* IFLA_IPTUN_TTL */ 2118 nla_total_size(1) + 2119 /* IFLA_IPTUN_ENCAP_LIMIT */ 2120 nla_total_size(1) + 2121 /* IFLA_IPTUN_FLOWINFO */ 2122 nla_total_size(4) + 2123 /* IFLA_IPTUN_FLAGS */ 2124 nla_total_size(4) + 2125 /* IFLA_IPTUN_PROTO */ 2126 nla_total_size(1) + 2127 /* IFLA_IPTUN_ENCAP_TYPE */ 2128 nla_total_size(2) + 2129 /* IFLA_IPTUN_ENCAP_FLAGS */ 2130 nla_total_size(2) + 2131 /* IFLA_IPTUN_ENCAP_SPORT */ 2132 nla_total_size(2) + 2133 /* IFLA_IPTUN_ENCAP_DPORT */ 2134 nla_total_size(2) + 2135 /* IFLA_IPTUN_COLLECT_METADATA */ 2136 nla_total_size(0) + 2137 /* IFLA_IPTUN_FWMARK */ 2138 nla_total_size(4) + 2139 0; 2140 } 2141 2142 static int ip6_tnl_fill_info(struct sk_buff *skb, const struct net_device *dev) 2143 { 2144 struct ip6_tnl *tunnel = netdev_priv(dev); 2145 struct __ip6_tnl_parm *parm = &tunnel->parms; 2146 2147 if (nla_put_u32(skb, IFLA_IPTUN_LINK, parm->link) || 2148 nla_put_in6_addr(skb, IFLA_IPTUN_LOCAL, &parm->laddr) || 2149 nla_put_in6_addr(skb, IFLA_IPTUN_REMOTE, &parm->raddr) || 2150 nla_put_u8(skb, IFLA_IPTUN_TTL, parm->hop_limit) || 2151 nla_put_u8(skb, IFLA_IPTUN_ENCAP_LIMIT, parm->encap_limit) || 2152 nla_put_be32(skb, IFLA_IPTUN_FLOWINFO, parm->flowinfo) || 2153 nla_put_u32(skb, IFLA_IPTUN_FLAGS, parm->flags) || 2154 nla_put_u8(skb, IFLA_IPTUN_PROTO, parm->proto) || 2155 nla_put_u32(skb, IFLA_IPTUN_FWMARK, parm->fwmark)) 2156 goto nla_put_failure; 2157 2158 if (nla_put_u16(skb, IFLA_IPTUN_ENCAP_TYPE, tunnel->encap.type) || 2159 nla_put_be16(skb, IFLA_IPTUN_ENCAP_SPORT, tunnel->encap.sport) || 2160 nla_put_be16(skb, IFLA_IPTUN_ENCAP_DPORT, tunnel->encap.dport) || 2161 nla_put_u16(skb, IFLA_IPTUN_ENCAP_FLAGS, tunnel->encap.flags)) 2162 goto nla_put_failure; 2163 2164 if (parm->collect_md) 2165 if (nla_put_flag(skb, IFLA_IPTUN_COLLECT_METADATA)) 2166 goto nla_put_failure; 2167 2168 return 0; 2169 2170 nla_put_failure: 2171 return -EMSGSIZE; 2172 } 2173 2174 struct net *ip6_tnl_get_link_net(const struct net_device *dev) 2175 { 2176 struct ip6_tnl *tunnel = netdev_priv(dev); 2177 2178 return tunnel->net; 2179 } 2180 EXPORT_SYMBOL(ip6_tnl_get_link_net); 2181 2182 static const struct nla_policy ip6_tnl_policy[IFLA_IPTUN_MAX + 1] = { 2183 [IFLA_IPTUN_LINK] = { .type = NLA_U32 }, 2184 [IFLA_IPTUN_LOCAL] = { .len = sizeof(struct in6_addr) }, 2185 [IFLA_IPTUN_REMOTE] = { .len = sizeof(struct in6_addr) }, 2186 [IFLA_IPTUN_TTL] = { .type = NLA_U8 }, 2187 [IFLA_IPTUN_ENCAP_LIMIT] = { .type = NLA_U8 }, 2188 [IFLA_IPTUN_FLOWINFO] = { .type = NLA_U32 }, 2189 [IFLA_IPTUN_FLAGS] = { .type = NLA_U32 }, 2190 [IFLA_IPTUN_PROTO] = { .type = NLA_U8 }, 2191 [IFLA_IPTUN_ENCAP_TYPE] = { .type = NLA_U16 }, 2192 [IFLA_IPTUN_ENCAP_FLAGS] = { .type = NLA_U16 }, 2193 [IFLA_IPTUN_ENCAP_SPORT] = { .type = NLA_U16 }, 2194 [IFLA_IPTUN_ENCAP_DPORT] = { .type = NLA_U16 }, 2195 [IFLA_IPTUN_COLLECT_METADATA] = { .type = NLA_FLAG }, 2196 [IFLA_IPTUN_FWMARK] = { .type = NLA_U32 }, 2197 }; 2198 2199 static struct rtnl_link_ops ip6_link_ops __read_mostly = { 2200 .kind = "ip6tnl", 2201 .maxtype = IFLA_IPTUN_MAX, 2202 .policy = ip6_tnl_policy, 2203 .priv_size = sizeof(struct ip6_tnl), 2204 .setup = ip6_tnl_dev_setup, 2205 .validate = ip6_tnl_validate, 2206 .newlink = ip6_tnl_newlink, 2207 .changelink = ip6_tnl_changelink, 2208 .dellink = ip6_tnl_dellink, 2209 .get_size = ip6_tnl_get_size, 2210 .fill_info = ip6_tnl_fill_info, 2211 .get_link_net = ip6_tnl_get_link_net, 2212 }; 2213 2214 static struct xfrm6_tunnel ip4ip6_handler __read_mostly = { 2215 .handler = ip4ip6_rcv, 2216 .err_handler = ip4ip6_err, 2217 .priority = 1, 2218 }; 2219 2220 static struct xfrm6_tunnel ip6ip6_handler __read_mostly = { 2221 .handler = ip6ip6_rcv, 2222 .err_handler = ip6ip6_err, 2223 .priority = 1, 2224 }; 2225 2226 static struct xfrm6_tunnel mplsip6_handler __read_mostly = { 2227 .handler = mplsip6_rcv, 2228 .err_handler = mplsip6_err, 2229 .priority = 1, 2230 }; 2231 2232 static void __net_exit ip6_tnl_destroy_tunnels(struct net *net, struct list_head *list) 2233 { 2234 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 2235 struct net_device *dev, *aux; 2236 int h; 2237 struct ip6_tnl *t; 2238 2239 for_each_netdev_safe(net, dev, aux) 2240 if (dev->rtnl_link_ops == &ip6_link_ops) 2241 unregister_netdevice_queue(dev, list); 2242 2243 for (h = 0; h < IP6_TUNNEL_HASH_SIZE; h++) { 2244 t = rtnl_dereference(ip6n->tnls_r_l[h]); 2245 while (t) { 2246 /* If dev is in the same netns, it has already 2247 * been added to the list by the previous loop. 2248 */ 2249 if (!net_eq(dev_net(t->dev), net)) 2250 unregister_netdevice_queue(t->dev, list); 2251 t = rtnl_dereference(t->next); 2252 } 2253 } 2254 2255 t = rtnl_dereference(ip6n->tnls_wc[0]); 2256 while (t) { 2257 /* If dev is in the same netns, it has already 2258 * been added to the list by the previous loop. 2259 */ 2260 if (!net_eq(dev_net(t->dev), net)) 2261 unregister_netdevice_queue(t->dev, list); 2262 t = rtnl_dereference(t->next); 2263 } 2264 } 2265 2266 static int __net_init ip6_tnl_init_net(struct net *net) 2267 { 2268 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 2269 struct ip6_tnl *t = NULL; 2270 int err; 2271 2272 ip6n->tnls[0] = ip6n->tnls_wc; 2273 ip6n->tnls[1] = ip6n->tnls_r_l; 2274 2275 if (!net_has_fallback_tunnels(net)) 2276 return 0; 2277 err = -ENOMEM; 2278 ip6n->fb_tnl_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6tnl0", 2279 NET_NAME_UNKNOWN, ip6_tnl_dev_setup); 2280 2281 if (!ip6n->fb_tnl_dev) 2282 goto err_alloc_dev; 2283 dev_net_set(ip6n->fb_tnl_dev, net); 2284 ip6n->fb_tnl_dev->rtnl_link_ops = &ip6_link_ops; 2285 /* FB netdevice is special: we have one, and only one per netns. 2286 * Allowing to move it to another netns is clearly unsafe. 2287 */ 2288 ip6n->fb_tnl_dev->features |= NETIF_F_NETNS_LOCAL; 2289 2290 err = ip6_fb_tnl_dev_init(ip6n->fb_tnl_dev); 2291 if (err < 0) 2292 goto err_register; 2293 2294 err = register_netdev(ip6n->fb_tnl_dev); 2295 if (err < 0) 2296 goto err_register; 2297 2298 t = netdev_priv(ip6n->fb_tnl_dev); 2299 2300 strcpy(t->parms.name, ip6n->fb_tnl_dev->name); 2301 return 0; 2302 2303 err_register: 2304 free_netdev(ip6n->fb_tnl_dev); 2305 err_alloc_dev: 2306 return err; 2307 } 2308 2309 static void __net_exit ip6_tnl_exit_batch_net(struct list_head *net_list) 2310 { 2311 struct net *net; 2312 LIST_HEAD(list); 2313 2314 rtnl_lock(); 2315 list_for_each_entry(net, net_list, exit_list) 2316 ip6_tnl_destroy_tunnels(net, &list); 2317 unregister_netdevice_many(&list); 2318 rtnl_unlock(); 2319 } 2320 2321 static struct pernet_operations ip6_tnl_net_ops = { 2322 .init = ip6_tnl_init_net, 2323 .exit_batch = ip6_tnl_exit_batch_net, 2324 .id = &ip6_tnl_net_id, 2325 .size = sizeof(struct ip6_tnl_net), 2326 }; 2327 2328 /** 2329 * ip6_tunnel_init - register protocol and reserve needed resources 2330 * 2331 * Return: 0 on success 2332 **/ 2333 2334 static int __init ip6_tunnel_init(void) 2335 { 2336 int err; 2337 2338 if (!ipv6_mod_enabled()) 2339 return -EOPNOTSUPP; 2340 2341 err = register_pernet_device(&ip6_tnl_net_ops); 2342 if (err < 0) 2343 goto out_pernet; 2344 2345 err = xfrm6_tunnel_register(&ip4ip6_handler, AF_INET); 2346 if (err < 0) { 2347 pr_err("%s: can't register ip4ip6\n", __func__); 2348 goto out_ip4ip6; 2349 } 2350 2351 err = xfrm6_tunnel_register(&ip6ip6_handler, AF_INET6); 2352 if (err < 0) { 2353 pr_err("%s: can't register ip6ip6\n", __func__); 2354 goto out_ip6ip6; 2355 } 2356 2357 if (ip6_tnl_mpls_supported()) { 2358 err = xfrm6_tunnel_register(&mplsip6_handler, AF_MPLS); 2359 if (err < 0) { 2360 pr_err("%s: can't register mplsip6\n", __func__); 2361 goto out_mplsip6; 2362 } 2363 } 2364 2365 err = rtnl_link_register(&ip6_link_ops); 2366 if (err < 0) 2367 goto rtnl_link_failed; 2368 2369 return 0; 2370 2371 rtnl_link_failed: 2372 if (ip6_tnl_mpls_supported()) 2373 xfrm6_tunnel_deregister(&mplsip6_handler, AF_MPLS); 2374 out_mplsip6: 2375 xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6); 2376 out_ip6ip6: 2377 xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET); 2378 out_ip4ip6: 2379 unregister_pernet_device(&ip6_tnl_net_ops); 2380 out_pernet: 2381 return err; 2382 } 2383 2384 /** 2385 * ip6_tunnel_cleanup - free resources and unregister protocol 2386 **/ 2387 2388 static void __exit ip6_tunnel_cleanup(void) 2389 { 2390 rtnl_link_unregister(&ip6_link_ops); 2391 if (xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET)) 2392 pr_info("%s: can't deregister ip4ip6\n", __func__); 2393 2394 if (xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6)) 2395 pr_info("%s: can't deregister ip6ip6\n", __func__); 2396 2397 if (ip6_tnl_mpls_supported() && 2398 xfrm6_tunnel_deregister(&mplsip6_handler, AF_MPLS)) 2399 pr_info("%s: can't deregister mplsip6\n", __func__); 2400 unregister_pernet_device(&ip6_tnl_net_ops); 2401 } 2402 2403 module_init(ip6_tunnel_init); 2404 module_exit(ip6_tunnel_cleanup); 2405